CA2205917A1 - Absorbent composites and absorbent articles containing the same - Google Patents

Abstract

Absorbent composites containing particles of absorbent gelling material and chemically stiffened, cellulosic fibers, the fibers being wrapped around and adhered to the particles, which are in individual form. The chemically stiffened, cellulosic fibers are preferably cellulosic fibers in substantially individual form having a crosslinking agent reacted with the fibers in intrafiber crosslink bond form. The absorbent composites are particularly suitable for use in the absorbent core of disposable absorbent articles such as sanitary napkins and diapers.

Description

CA 0220~917 1997-0~-22 Wo 961~7573 PCT/US9~/15789 ABSORBENT COMPOSITES AND
ABSORBENT ARTICLES CONTAINING THE SAME
..

Field of the Invention The present invention relates to absorbent composites containing one or more individual particles of absorb~"~ gelling r"aLerial the particles-having chemically slirrt ned cellulosic fibers wrapped around and adhered to the pallicles and to methods of making the abso,be"L co""~osiles. The absorb~"l co"",osites are especially suitable for use in the absorbent core 15 component of dispos~hle absorbent articles such as fe" ,i"i"e hygiene articles and diapers.

Backaround of the Invention AbsorL,el,l gelling ",dterials (also referred to as hydrogels 20 superdbsorL,e, ll or hydrocolloid materials and I ,erei,1drler aller"dli~/elyrere"ed to as "AGM" or in the plural "AGMs") are capable of absorbing large quantities of liquids such as water and body ex~d~tes and of ,~tainir,g such abso" ed liquids under moderale pressures. These absorption ~ 1 ,ar~c1erislics make them especially suitable for use in disposable 25 absGrL,er,t articles such as ~iapers sanilary oapl~i"s illcol,Line,ll devicesand the like. Partiall~te AGMs are typically ~lisposed in and/or on webs of absorL,ent fibers in the abso,L,ent core cor"~ol)enl of such articles. For ~ exa,n~.le U.S. Patent 3 699 103 issued to Harper et al. on June 13 1972 and U.S. Patent 3 670 731 issued to Harmon on June 20 1972 both 30 disclose the use of particul~te AGM in absorbent articles.

Conve"tio~al particulate AGMs however have the li",ilalion that the pallicles are not immobilized and are free to ",iy,dle during processing and/or use. Miyl dlio, I of the particles during processing can lead to "~a~erial handling losses during manufacturing operations and, more CA 0220~917 1997-0~-22 significantly, the nonhomogeneous incorporation of the particles into structures in which the particles are being used. Nonhomogeneous incorporation of the particles can result in regions of relatively high concentration of the particulate material. When the particles are wetted, 5 such high conce"l,dLion regions tend to exhibit high resistance to liquid flow, i.e., gel blocking. Gel blocking is a particular problem where relatively high gel volume, low gel strength AGMs are used. As a result, the acquisition and/or distribution of liquids by the absorbent article is diminished, leading to inefficient utilization of the article and/or leakage.
As a result of product design or migration, the particles may be present in the vicinity of the topsheet or backsheet. The presence of the absorbent particles in these regions tends to cause a gritty feeling to the wearer, pinholing of the backsheet resulting in aesthetic negatives andfor leakage, and/or migration through the topsheet causing gel on the wearer's 15 skin.
One approach to address the migration of particulate hydrogels in absorbent articles is disclosed in U.S. 3,901,236 issued to Assar:,son et al.
on August 26, 1975. Assarsson discloses particulate hydrogels substantially coated with fibers, for example, conventional wood pulp fibers.
20 Other composites comprising particulate absorbent materials with fibers, such as synthetic polymeric fibers or conventional wood pulp fibers, adhered thereto or e",bedded therein are disclosed in U.S. 5,230,959 issued to Young, Sr., et al. on July 27,1993 and in U.S. 5,002,814 issued to Knack, et al. on March 26, 1991, respe~ ely.
While some of the problems of reducing migration of particulate AGM
",dlerials have been at least partially ameliorated by previously disclosed techl lolGyy~ none has solved the problems in the r"a""er or to the extent of the present invention. For example, it has been found that ordinary wood pulp fibers are less effective than the chemically slirrened, cellulosic fibers in minimizing the migration of AGM particles. In addition, the absorbent efficacy of the aforementioned materials tends to be limited as compared to the db50l b el ,t composites of the present invention. In particular, the chemically stiffened, cellulosic fibers tend to impart faster ~c~uisition times,higher rates of fluid absorption, and higher fluid reter,liol1s to the composites, as co, l "~ared to ordinary wood pulp fibers or synthetic polymeric fibers.

WO 96/17573 PCI~/US95/15789 Thus, there i~.- an ~going~need to minimize the migration of particulate AGMs in absorbent articles. Moreover, there is a continuing need to improve the absGrbel)t efficacy (including fluid acquisition rates and fiuid retentions) of absorbent articles incorporating particulate AGMs. It is especially desirable to provide absorbenl articles of the thinnest possible configuration consistent with such ~bsGrbent efficacy.
It is therefore an object of the present invention to provide particulate, absorbent gelling materials that are relatively immobile and thus not free to migrate within or out of the absorbent cores of absG, L,ent articles, 10 particularly absorbent cores corlai. ~ing hydrophilic fibers. Another object is to provide absGrbei)l members formed from or containing such particulate, absorbent gelling materials. Still another object of the pr~sel,l invention is to provide absorbent articles containing these abso,~e"l gelling materi~s, which articles do not suffer from the problems of aesthetics, pin-holing, 1~ and/or gel on skin. Yet another object of the present invention is to provideabsorbent articles of relatively thin configuration that meet or exceed the absorbent efficacy of a~so~ benl articles known here~oror~.

Summarv of the Invention The present invention relates to absorbent composites that co"ldin particulate AGM and chemically stiffened, cellulosic fibers, and to absorbent members and articles com~risi"g such a colllposile. A co",posite of the present invention CGnldil IS one or more AGM particles and chemically stiffened, cellulosic fibers that are wrapped around and adhered to the 2~ particles in individual form, with a suL,slanlial portion of the fiber endsprotrudin~ from the surface of the particles. The fibers can be adhered to the particles by embedment in the polymeric material of the particles, by a bonding agent, or a combination lil~reof. In a ~,rere,led embodiment, the fibers are adhered to the AGM particles through the use of a bonding agent.
In a prere,led embodi~"e"~, the chemically slirrened, cellulosic fibers of the composite have i"l,driber crosslink bonds formed by crosslinking the fibers while they are in a relatively dehydrated, deribraled (i.e., individualized), twisted, curled condition.
The absorL,el ,t composites are pte~erably prepared by a method that 3~ incllldes the steps of: (1) applying a bonding agent in liquid form onto the CA 0220~917 1997-0~-22 chemically stiffened, cellulosic fibers to form treated fibers; (2) physically associating particles of polymeric, absorbent gelling material and the treated fibers while the bonding agent is in liquid form and the particles are in substantially individual form, such that the fibers wrap around the 5 particles and the fiber ends protrude from the particles; and (3) adhering theparticles and the fibers. In a ,urefer,ed embodiment, the bonding agent is applied to a web containing the chemically stiffened, cellulosic fibers.
Accordi"g to this embodiment, the fibers that are wrapped around and adhered to a given AGM particle are mechanically 5~hsPrltially separated 10 from the fibers that are wrapped around other AGM particles.
The present invention also relates to absorbent members comprising the composite. The absorbent member may consist essentially of the composite or may contain other absorbent materials. In a prerer~d embodiment, the absorbent member comprises the composite and an 15 absorbent carrier means, e.g., a web of hydrophilic fibers, the composite being SUbSldl ,lially homogeneously dispersed, more preferably homogeneously dispersed, in the absorbent carrier means.
The present invention also relates to absorbent articles, for exampie, feminine hygiene articles and diapers, cGr~".,isi"g the absGrbenl cG"~,osile.
20 In a prefer,ed e",bodi,l~e,ll, the al,sorL,e"t article has an absorbent member that comprises the cGI"posite and an absorbent carrier means, prererably as described above.
The AGM particles of the absorbent CGI I ,~ osile tend to be immobilized by the fibrous wrap when the absG, bel ,t composite is 25 incorporated into fibrous absorbent structures. Thus, the problems ~ssoc,~led with migration of AGM particles are minimized. Moreover, the ~a, licles are individually cushioned by the fibersl thereby te, Idil lS~ to reduce negative aesll,elic results and pinholing, and to increase wearer c~",ro,l.
The absorL~e"t composites of the present invention provide improved 30 absGrbenl properties relative to fiberlAGM composites known heretorore. It has been found by the present inventors that the chemically stiffened, cellulosic fibers employed in the absorbent composites of the present invention provide benefits that are not achieved with Grdi"ary wood pulp fibers or synthetic polymeric fibers.

CA 0220~917 1997-0~-22 WO 96/17S73 PCT/US95/lS789 More specifically it has been found that the relatively stiff synthetic polymeric fibers have a higher resistance to wrapping around the AGM
particles than the chemically ~lirrened cellulosic fibers employed in the present invention. In addition the synthetic fibers are cylindrically shaped 5 while the chemically ~lirre,led cellulosic fibers are very thin and flat. As aresult the synthetic polymeric fibers tend to attach at various discrete spots on the AGM particles, typically at one or two spots while the chemically stiffened cellulosic fibers tend to confo"" to the shape of the AGM particle.
Any point of attachment of the chemically stiffened cellulosic fibers thus 10 tends to have a high AGM-fiber contact surface area relative to the synthetic polymeric fibers. As a result a lesser number of the chemically slirrel ,ed cellulosic fibers than the sy, Ill ,elic polymeric fibers is required for wrapping around the AGM particles to provide the benefits of the fiber wrap.
Thus the present invention may enable absorbent me",ber~ containing 1~ relatively high AGM co"c~l,L~aLions which are particularly useful in thin absorL,ent article designs.
On the other hand conv~"Lio"al wood pulp fibers are very soft and pliable relative to the chemically ~lirr~l ,ed cellulosic fibers employed in thepresenL invention. Such wood pulp fibers tend to totally wrap around or 20 co"rur"~ to the AGM particles such that the fiber ends do not protrude or only protrude to a relatively minimal degree. When cGIlL2~Led with fluids the fluid must first peneL,a~e the wood pulp fiber wrap before contacting the AGM particle. Once the AGM particle is wetted it tends to suffer from some resistance to swelling since it is co"~L,di"ed by the wood pulp wrap. In 25 contrast, the chemically Slirrel ,ed, cellulosic fibers co, ~rurl " less intimately to the shape of the AGM particle such that larger void sp~ces tend to be present within the fiber wrap. As a result the chemically ~Lirre"ed cellulosic fiber wrapped AGM particles tend to have a faster fluid absorption rate and a higher fluid absorption capacity under pressure and fluid 30 retenLiG".
The ability of the fiber ends of the chemically stiffened cellulosic fibers to protrude from the AGM particles tends to minimize migration of the particles in the abs~, beul articles i"cor~.orali"g the co" ".osile of the present invention relative to composites of absorbent particles and ordi"ary 35 wood pulp fibers. The protrusion also tends to increase the absorbent ,uro,~,e,lies (including the fluid t-ele"lio,) acquisition time and absorption CA 0220~917 1997-0~ 22 WO ~6tl7S73 PCT/US95tl5789 rate) of the absorbent articles relative to those containing composites of AGM particles and ordinary wood pulp fibers.

Brief DescriPtion of the Drawinqs Figure 1 is a photomicroy,~ ll of an absorbent composite accor:li"g to the present invention.
Figure 2 is an apparalus suitable for use in forming the absorbent composites of the present invention.
Figure 3 is an absorbent article in the form of a sanitary napkin according to the present invention.
Figure 4 is a cross-sectional view along the line 44 of Figure 3.
~igure 5 is an absorbent article in the form of a diaper accordi"g to the present invention.

Detailed Desc,i~liGn of Prerer,ed Embodi",enls The absorbent composites of the present invention contain particles of absorbent gelling material (AGM) and chemically stiffened, cellulosic fibers.
By "particles", "particulate" and the like it is meant that the absorbent 20 gelling material is in the form of discrete units. The particles can comprisegranules, pulverulents, spheres, flakes, or fibers. Thus, the particles can have any desired shape such as cubic, rod-like, polyhedral, spherical, rounded, angular, irregular, ra"do",ly-sized irregular shapes (e.g., pulverulent products of a grinding or pulverizing step) or shapes having a 25 large greatest dimension/smallest di",ensiol, ratio like needle-like, flake-like, or fibrous shapes, and the like. Although the particles may have sizes varying over a wide range, the particle size typically ranges from about 1 micron to about 2000 microns in diameter or cross-section, and preferably ranges from about 50 microns to about 1000 microns.
Absorbent gelling materials are capable of absorbing large quantities of liquids such as water and body exl ~d~tes, and of retaining such absorbed liquids under moderate pressures. Although the selection of the absorbent gelling material is not critical to the present invention, typical and prefer,ed CA 0220~9l7 l997-0~-22 WO 96/17573 PCT/US9!;/lS789 absorbent gelling materials are described in U.S. Patent Re. 32,649, reissued to Brandt et al. on April 19, 1988; U.S. Patent 4,666,983, issued to Tsubakimoto et al. on May 19, 1987; and U.S. Patent No. 4,625,001, issued to Tsubakimoto et al. on November 25, 1986; each of these pale"ls being incorporated herein by reference. The AGMs are typically suhsp~tially water-insoluble, absorbent, hydrogel-forming, polymeric materials. Mixtures of absorbent gelling materials may also be used.
P,efer~ed absorbe, ll gelling materials for use in the present invention possess a carboxyl group. These materials include hydrolyzed starch-acrylonitrile graft copolymer, partially neutralized starch-acrylonitrile graft copolymer, starch-acrylic acid graft copolymer, partially neutralized starch-acrylic acid graft copolymer, vinyl ~set~te-acrylic ester copolymers, saponified vinyl acetate-acrylic ester copolymers, hydrolyzed acrylonitril~or acrylamide copolymers, slightly network crosslinked products of any of the foregoing polymers, partially neutralized polyacrylic acid, and slightly network crosslinked products of partially neutralized polyacrylic acid.
These polymers may be used either independently or in an admixture of two or more of the polymers. Examples of these polymer materials are disclosed in U.S. Patents 3,661,875; 4,076,663; 4,093,776; 4,666,983; and 4,734,498. Most preferably, the absorbent gelling material is a slightly network crosslinked product of partially neutralized polyacrylic acid or a starch derivative thereof.
The ~L)sol~ent gelling material is prerera~ly ,~re,~ared by aqueous solution or other solution poly~eri~dlio" Illelilods, such as des.;libed in the above-rere,e"ced U.S. Patent Re. 32,649. However, it is also possible to use a6sGr~ent gelling ",aterials prepared by other metllods as are well known in the art, for example, multi-phase polymerization ~,(ocessi"g techniques such as inverse emulsion pol~""e,i~alion or inverse suspension pol~",eli~dlion procedures. For example, inverse emulsion polymeri dliGIl ~ 30 techniques are ~l~sc,ibed in U.S. Patent 4,340,706, issued to Obayashi et al. on July 20, 1982; U.S. Patent 4,506,052, issued to Fletcher et al. on ~ March 19, 1985; and U.S. Patent 4,735,987, issued to Morita et al. on April 15, 1988; each of these ~atents being incor~ordled herein by reference.
The particles of abso,benl gelling ~aterial may optionally be surface treated. For example, U.S. Patent 4,824,901, issued to Alexa,-der et al. on April 25, 1989, discloses the suRace treatment of polymeric particles with a CA 0220~917 1997-0~ 22 poly-quaternary amine. If surface treated, the particles are preferably surface treated as described in U.S. Patent 4,734,478, issued to Tsubakimoto et al. on March 29, 1988, incorporated herein by reference;
and in the above-referenced U.S. Patent 4,666,983.
P~ t fer, ed absorbent gelling materials exhibit a high absorptive capacity. Absorptive capacity refers to the capacity of a given polymer material to absorb liquids with which it comes into conlacl, and can vary significantly with the nature of the liquid being absorbed and with the manner in which the liquid conla~ the polymer material. For purposes of this invention, Absorptive Capacity is defined in terms of the amount of Synthetic Urine absorbed by any given polymer material in terms of grams of Synthetic Urine per gram of polymer material. Plefer,ed absorbent gelling materials of the present invention are those which have ~n Absorptive Capacity of at least about 20 grams, more ,c,refer~bly at least about 25 grams, of Synthetic Urine per gram of polymer material. Typically, the polymer materials herein have an Absor~ e Capacity of from about 40 to about 70 grams of Synthetic Urine per gram of polymer material. A
method for determining the AbsGr~live Capacity for partiu-l~te, absorbent, polymeric compositions, which can be used herein, is desc~ibed in U.S.
Patent 5,300,565, issued to Berg et al. on April 5, 1994. This patent is incorporated herein by reference.
The absorbent composite of the presel ,1 invention also contains chemically stiffened, cellulosic fibers. Cellulosic fibers are well known and include, for example, digested fibers from softwood, hardwood or cotton linters, Esparto grass, bagrasse, hemp, and flax. Fibers from other Iiy~ceous and cellulosic fiber sources may also be used herein. The abso, I,ent composites may contain one or more types of chemically stiffened, cellulosic fibers.
As used herein, the term "chemically slirr~ned cellulosic fibers"
means cellulosic fibers which have been slirrer,ed by chemical means to increase stiffness of the fibers under both dry and aqueous conditions.
Such means include the addition of chemical stiffening agents which, for example, coat and/or impregnate the fibers. Such means also include the slirreoi"g of the fibers by altering the chemical structure of the fibers themselves, e.g., by cross-linking polymer chains.

CA 0220~917 1997-0~-22 WO 96/17S73 . P~;11 LJ~3S/15789 For exemplary purposes, polymeric stiffening agents which can coat or impregnate cellulosic fibers include: cationic modified starch having nitrogen-containing groups (e.g., amino groups) such as those available ~, from National Starch and Chemical Corp., Bridgewater, NJ, USA; latex; wet strength resins such as polyamide-epichlorohydrin resin (e.g., Kymene~
557H, Hercules, Inc. Wilmington, Delaware, USA), polyacrylamide resin (described, for example, in U.S. Patent 3,556,932 issued January 19, 1971 to Coscia, et al.; also, for example, the commercially available polyacrylamide marketed by American Cyanamid Co., Stallrord, CT, USA, under the tradename ParezTM 631 NC); urea formaldehyde and melamine formaldehyde resins, and polyethylenimine resins. A general dissertation on wet sl,enyll, resins utilized in the paper art, and generally applicable herein, can be found in TAPPI monograph series No. 29., "Wet Strength in Paper and Paperboard", Technical Association of the Pulp and Paper Industry (New York, 1965), il ,co~ ,uorated herein by reference.
The fibers utilized in the composites herein can also be stiffened by means of chemical reaction. For example, crosslinking agents can be applied to the fibers which, subsequent to application, are caused to chemically form intra-fiber crosslink bonds. These crosslink bonds can increase the stiffness of the fibers. Whereas the utilization of intrafiber crosslink bonds to chemically stiffen the fibers is prefer,ed, it is not meant to exclude other types of reacliG"s for chemical slirrenin~~ of the fibers.
Fibers slirrened by crosslink bonds in individualized (i.e., fluffed) form are disclosed, for example, in Ber.,arclir), U.S. Patent 3,224,926, issuedDece",ber21, 1965; Chung, U.S. Patent3,440,135, issuedApril22, 1969; Cl,dllerjee, U.S. Patent 3,932,209, issued January 13, 1976 and Sangenis et al., U.S. Patent 4,035,147, issued July 12, 1977. More ~re~er,ed fibers are disclosed in Dean et al., U.S. Patent 4,822,453, issued April 18, 1989; Dean et al., U.S. Patent 4,888,093, issued December 19, ~ 30 1989; Scllog~e,l et al., U.S. Patent 4,889,596, issued December 26, 1989;
Herron et al., U.S. Patent 4,889,595, issued December 26, 1989; Moore et al., U.S. Patent 4,898,642, issued February 6, 1990; Herron et al., U.S.
Patent 5,183,707, issued February 2, 1993; and Herron et al., U.S. Patent 5,190,563, issued March 2, 1993. All of these ,udLellls are incorporated herein by r~rer~"ce.

CA 0220~917 1997-0~-22 In the more preferred stiffened fibers, chemical processing includes intrafiber crosslinking with crosslinking agents while such fibers are in a relatively dehydrated, defibrated (i.e., individualized), twisted, curled condition. The effect of crosslinking while such individualized (i.e., fluffed) 5 fibers are in this condition is to form fibers which are stiffened and which tend to retain their twisted, curled configuration during use in the absorbent articles herein. Such fibers, and processes for making them are described in the above incGr,c orated patents.
Suitable chemical stiffening agents that can be used for such 10 intrafiber crosslinking include mo"oi~eric crosslinking agents including, but not limited to, C2-Cg dialdehydes, C2-Cg monoaldehydes having an acid functionality, acid analogues of C2-Cg dialdehydes having at least one aldehyde functional group, and oligomers of any of the forementior~ed compounds. These compounds are capable of reacting with at least two 15 hydroxyl groups in a single cellulose chain or on proximately located cellulose chains in a single fiber. Such crosslinking agents co"le",,~lated for use in preparing the stiffened cellulose fibers include, but are not limitedto, glutaraldehyde, glyoxal, formaldehyde, and glyoxylic acid. Cellulosic fibers stiffened by such crosslinking agents and methods of making the 20 same are described in the above-refe(enced and incor~ Graled U.S. Patents 4,888,093; 4,898,642; 4,889,595; and 4,889,596.
Most prer~rably, the chemical stiffening agent that is employed for intrafiber crosslinking is a polycarboxylate. Suitable polyca, boxylates include C2 - Cg polycarboxylic acids, including aliphatic and alicyclic C2 -25 Cg polycarboxylic acids either olefinically saturated or unsaturated and having at least three calboxyl groups per molecule; and aliphatic and alicyclic C2 - Cg polycarboxylic acids having two call.oxyl groups per molecule and having a carbon-carbon double bond located alpha, beta to one or both of the carL,oxyl groups. A given carboxyl group in such C2 - Cg 30 polycarboxylic acid crosslinking agents is separated from a second carboxyl group by no less than two and no more than three carbon atoms. Prefer,ed crc,sslinhi"g agents of this type are citric acid; 1,2,3 butane tetracarboxylic acid; 1,2,3 propane tricarboxylic acid; oxydisuccinic acid; ta, L, dle monosuccinic acid; ~al~lale dis!~ccinic acid, or a mixture thereof. More 35 ~Jr~ferably, the crosslinking agent is citric acid. The fibers crosslinked with a C2 - Cg polycarboxylic acid will typically have between about 0.5 mole %

CA 0220~917 1997-0~-22 and about 10.0 mole % crosslinking agent, calcl ll~te~ on a cellulose anhydroglucose molar basis, more preferably between about 1.5 mole %
and about 6.0 mole % crosslinking agent, calculated on a cellulose ~, anhydroglucose molar basis, reacted therewith in the form of intrafiber ester crosslink bonds. Cellulosic fibers stiffened by crosslinking agents of this type and methods of making the same are described in the above-referenced and incorporated U.S. Patents 5,183,707 and 5,190,563.
The preferred stiffened fibers that are twisted and curled can be quantified by rererellcing both a fiber "twist count" and a fiber "curl factor".As used herein, the term "twist count" refers to the number of twist nodes present in a certain length of fiber. Twist count is utilized as a means of measuring the degree to which a fiber is rotated about its longitudinal axis.
The term "twist node" refers to a s~bst~rltially axial rotaLion of 180~ abeut the longitudinal axis of the fiber, wherein a portion of the fiber (i.e., the "node") ap,l~ears dark relative to the rest of the fiber when viewed under a mic,uscope with l,d"~",itted light. The twist node ar,pedrs dark at locations wherein the lrdns",itted light p~sses through an additional fiber wall due to the afore",entioned rotation. The distance between nodes cor,esponds to an axial rotaLio,) of 180~. The number of twist nodes in a certain length of fibers (i.e., the twist count) is directly indicative of the degree of fiber twist, which is a physical paral"eter of the fiber. The procedures for determining twist nodes and total twist count are described in the hereinbefore rerelel,ced U.S. Patent 5,183,707.
The prefe"ad slifral ,ed cellulose fibers, which are formed using a C2 - Cg polycarboxylic acid crosslinking agent, will have an average dry fiber twist count of at least about 2.5, ,c"aferdbly at least about 3.0 twist nodes per millimeter. Fu~Lhen~ora, the average wet fiber twist count of these fibers should prererably be at least about 1.5, ,u,ererably at least about 2.0, and should also ~.~eferably be at least about 1.0 twist nodes per millimeter ~ 30 less than the average dry fiber twist count.
In addition to being twisted, the prarer, ad chemically stiffened, ~ cellulosic fibers used in the composites of the present invention are also curled. Fiber curl may be described as the fractional shol l~ning of the fiber due to kinks, twists, and/or bends in the fiber. For the purposes of this invention, fiber curl is measured in terms of a two dimensional plane. The extent of fiber curling can be quantified by rererel,cing a fiber curl factor.

CA 0220~917 1997-0~-22 The fiber curl factor, a two dimensional measurement of curl, is determined by viewing the fiber in a two dimensional plane. To determine curl factor, the projected length of the fiber as the longest dimension of a two dimensional rectangle e"cG,npassing the fiber, LR, and the actual length of 5 the fiber, LA, are both measured. The fiber curl factor can then be calculated from the following equation:
Curl Factor = (LA/LR) - 1 An image analysis method that can be utilized to measure LR and LA
is described in U.S. Patent 5,183,707. Preferably the chemically stiffened, 10 cellulosic fibers utilized in the absorbent composites of the present invention will have a curl factor of at least about 0.30, and more preferably of at least about 0.50.
The degree of stiffening, dependent upon the type and amount of stiffening agent (i.e., crosslinking agent) used, the degree of dehydration of 15 the fibers during curing of the crosslinking agent, and the curing time and conditions, affect the ability of the fiber to take up fluid and the tendency ofthe fiber to swell. The fiber stiffness as it relates to resisla"ce to fiber wall swelling can be quantified by referencing the water retention value (WRV) of the stiffened cellulosic fibers used in the absorbent composites herein.
20 WRV is a measure of the amount of water retained by a mass of fibers after sl IhsPlltially all of the i"le, riber water has been removed. Another parameter which can be used to characterize the nature of the stiffened fibers formed by crosslil~hin~J fibers in relatively dehydrated forrrl is that of alcohol retention value (ARV). ARV is a measure of the extent to which a 25 fluid, e.g., isopropyl alcohol, which does not induce s~ sl~nlial fiber swelling, is taken up by the stiffened fibers. The ARV of the stiffened fibers is directly related to the extent that the fibers were swollen with the solutionof crosslinking agent during the stiffening procedure. Relatively higher ARVs mean that the fibers were generally swollen to a relatively greater 30 extent during crosslinking. Procedures for determining WRV and ARV are descl ibed in U.S. Patent 4,898,642.
The WRV for the slirr~"ed, twisted, curled fibers used in the present invention will preferably be less than about 60%, more ~.referably in the range of from about 28% to about 60%, even more pr~ferably from about 35 28% to about 50%. In more prefer,~d embodiments, the WRV of the fibers can range from about 30% to 45%. Fibers having a WRV within these _ _ _ _ _ _ _ _ _ _ _ _ _ _ .

CA 0220~917 1997-0~-22 ranges are believed to provide an optimal balance of swelling-induced untwisting and fiber stiffness.
The stiffened cellulose fibers preferred for use herein are those which have an ARV (isopropyl alcohol) of less than about 30%. The limitation that such fibers have an ARV (isopropyl alcohol) of less than about 30% is indicative of the relatively dehydrated, unswollen state of these fibers during the stiffening process. More preferably, the ARV
( jSGP~UP~/I alcohol) of the fibers useful herein will be less than about 27%.
The stiffened cellulose fibers herein having the prerer,ed twist count, curl factor, WRV and ARV characteristics hereinbefore set forth, can be prepared by internally crosslinking such fibers in relatively dehydrated form while or after such fibers are being or have been dried and defibrated (i.e., "fluffed") as described in U.S. Patents 4,888,093; 4,898,642; 4,889,5g5;
4,889,596; 5,183,707; and 5,190,563. It is not, however, meant to necess~rily exclude other chemically stiffened cellulosic fibers from this invention, such other fibers being described in (but not limited to) the previously i"cor~ol-ated U.S. Patents 3,224,926, 3,440,135, 4,035,147, and 3,932,209.
The relative amounts of particulate absorbent gelling material and chemically stiffened fibers in the composite of the present invention ranges from about 90% to about 30% AGM and from about 10% to about 70%
chemically ~lirre"e-l cellulosic fibers. P~ererably, the cG",posile conlains from about 70% to about 30% AGM and from about 30% to about 70%
c;ilelllically stiffened cellulosic fibers. More ~rererably, the cor"posile contains from about 65% to about 35% AGM and from about 35% to about 65% chemically slirrt:ned cellulosic fibers. Each of the foregoing perce"lages of AGM and fibers is based on the total weight of the composite.
The aL,sorbe"t col"posiles may also contain fibers other than the chemically stiffened, cellulosic fibers. For example, the absorbent composites may contain other hydrophilic fibers such as are known in the art, including ordinary wood pulp fibers or synthetic polymeric fibers, including polyolefin mono- or multi-cor"pG"ent fibers. The multicon~liluent fibers may contain two or more dirrere"t polymers. When used, such other fibers will typically be employed in amounts of up to about 50 % of the total weight of fibers in the absorbent co~"~osile. Such other fibers may be CA 0220~917 1997-0~ 22 ~4 adhered to the AGM particles such that the fiber ends protrude from the particles.
The chemically stiffened cellulosic fibers (and other fibers which may be present in the absorbent composite) are adhered to individual particles 5 of the absorbent gelling material. Adhesion should be sufficient to allow the chemically stiffened, cellulosic fibers to substantially immobilize the AGM
particles when incorporated into an absorbent member such as described herein. Thus, gel blocking and gel on skin is minimized or avoided.
Adhesion of the fibers and AGM can be caused by a number of methods.
10 For example, the fibers may be adhered to the AGM during the polymerization of the AGM, or by using a bonding agent. The AGM
polymerization method typically results in a portion of the polymeric material of the AGM mechanically engaging a sufficient portion of any individual fiber that may be in contact with the AGM particle so as to effect adherence.
15 Methods using a bonding agent may involve such mechanical engagement and addi~ionally involves the mechanical and/or chemical adhesion of the AGM particles and the fibers c~used by the bonding agent ",dlerial.
Thus, accor ;li"g to one method of preparing the composite, the fibers are adhered to the AGM particles during the polymericdliG,, process for 20 forming the AGM. As stated above, abso,bent gelling materials can be formed by solution polymeri a~ion methods or by reverse phase polymerization methods. The reacla"ls that form the AGM are in a homogeneous, continuous solution (solution polymeri alion) or in one phase of a mulli,c I ,ase, typically two-phase, solution (reverse phase 25 poly",eri~dliG,1). The fibers can be added to either of such solutions prior to the completion of the poly",eri~dliol, reaction to form the AGM. Upon poly",e, i~alion of the reactants, the fibers are at least partially e"l,d~Jped by the resultant polymer. In solution polymerization methods, the resultant polymeric product may be ground by methods such as are known in the art 30 of forming AGM particles. The polymeric product is preferably dried by known methods, prior to any grinding. In reverse phase polymerization ,netl ,ods, the polymeric product is recovered by known methods, for example, centrifugation, filtration andlor eva~.ordLio". Extemal forces as described below are preferably applied, during or after polymerization, to 35 prc,r"o~e wrapping of the AGM particles by the embedded fibers.

CA 0220S917 1997-0~-22 W O96tl7573 PCTrUS9S/15789 In a prerer~ed embodiment, adhesion of the fibers and AGM is achieved with the use of a bonding agent. In general, the bonding agent includes substances that can be applied in liquid form to the fibers to allow its presence on the fibers to cause alLacl,ment of the AGM and the fibers.
5 The bonding agent must also be suitable for adhering the AGM material and the fiber material. In general, the bonding agent causes the mechanical and/or chemical adhesion of the AGM particles and the fibers.
Without intending to be bound by theory, it is believed that the bonding agent predisp~ses the AGM to wetting. As a result, the bonding agent 10 tends to improve the absorbent (i.e., absorption) capacily and rate of absorption of absorbent me,lliJe~ incorporating composites accordi"g to this embodiment.
The selection of a particular bonding agent will typically depend~n the cl,emical composition of the AGM and the fiber r"aLerial and can be 15 made by one skilled in the art with a knowledge thereof. P(erarably, the bonding agent is suitable for use in applications involving human co"ta~;t, for example, the ~~is )os~.le absorbent articles herein. Thus, the bonding agent should be non-toxic and non-i" iLali"g to humans. Mixtures of bonding agents may be used.
Several types of bo"-liny agents are suitable for use herein. Without intending to be bound by theory, it is believed that one type of bonding agent c~uses the polymer material of the particles to adhere to the fibers by the action of fluid surface te, ISio,) forces and/or the entanglement of polymer chains due to external softening. Bonding agents of this type include (1) hyd,u~Jl,ilic organic solvents, typically low molecular weight alcohols, for example"nelh~nol, ethanol, iso~.r~,panol and the like, ûr polyols, for example, propylene glycol, glycerol and the like; (2) water; (3) volatile hyd~o~l ,oL,ic organic compounds, for example, hexane, octane, benzene, toluene and the like; and (4) mixtures thereof. r,t:re"ed bondi~,g agents of this type are hydrophilic organic solvents, water, and a mixture thereof. These bonding agents particuiarly tend to predispose the AGM to ~ wetting, such that they tend to improve the absorbent capacily and rate of abso,~Lio" of the co",posiles. More prerer~bly, bonding agents of this type are selected frûm water, glycerol, propylene glycol, and mixtures thereof.
Other bonding agents tend to rely less or not at all on the fluid surface tension forces and/or the entanglement of polymer chains of CA 0220~917 1997-0~-22 WO 96/17S73 PCI~/US95/15789 swollen AGM particles for adhesion to the fibers. This type of bonding agent typically involves mechanical and/or chemical i"teraclion between the bonding agent, fiber, and the AGM particles. For example, the bonding agent may form bridges between the AGM and the fibers. This type of 5 bonding agent is pre~r,ecJ for use herein since it tends to provide sl,onger attachment between the fibers and AGM. Bonding agents of this type include, for example, cationic polyacrylamides, cationic amino-epichlorohydrin ~dd~cts, and mixtures thereof. Such bonding agents are preferably employed in an aqueous mixture.
In the most prefer~ad embodil"er,ls of the present invention, the bonding agent includes water. The presence of water in the bonding agent is particularly effective in predisp~sing the AGM to wetting. The bonding agent pre~erably contains at least about 60% water, by weight of t~e bonding agent, with the balance consisting essenlially of at least one non-15 aqueous bonding agent. Non-a~ueo~ ~s bonding agents include the aforementioned hydrophilic organic solvents, volatile hydrophobic compounds, cationic polyacrylamides, and cationic amino-epichlorohydrin adducts. The bonding agent more ~,r~ferdbly col llains from about 80% to about 90% water and from about 20% to about 10% of at least one non-20 aqueous bonding agent, based on the total weight of the bonding agent.
Cationic polyacrylamides are well known in the art. For example,cationic polyacrylamides that are suitable for use in the present invention are described in PUIP and PaPer: Chemistrv and Chemical Technoloqv, 3rd.
Ed., Vol. lll, edited by James P. Casey, pp. 1458-1471 (John Wiley & Sons, 25 1981), incorporated herein by reference. Suitable cationic polyacrylamides are commercially available from the American Cyanamid C~"~par,y of Wayne, NJ, under the trade name of ACCOSTRENGTH~. For example, ACCOSTRENGTH~ 410, 711, 200, 85 and 86 resins are available. These resins are described in the technical brochure number PCT-729/1-10274K-30 11/81, entitled "ACCOSTRENGTH(~ resins," the American CyanamidCom~any, November 1981, incorporated herein by reference.
As used herein, "cationic amino-epichlorohydrin adduct" refers to the reaction product between epichlorohydrin and a monomeric or polymeric amine such that the resulting reaction product has at least two cationic 35 functional groups. These ~ddl ~cts can be in the form of monomeric compounds (e.g., the reaction product of epichlorohydrin and ethylene CA 0220~917 1997-0~-22 WO 96/17S73 1 ~ 51l5789 diamine), or can be in polymeric form (e.g., the reaction product between epichlorohydrin and polyamide-polyamines or polyethyleneimines). The polymeric versions of these cationic amino-epichlorohydrin ~-idl ~ct~ are typically referred to as "resins."
Monomeric amines that can be t~acted with epichlorohydrin to form a cationic amino-epichlorohydrin include monomeric di-, tri- and higher amines having primary or secondary amino groups in their structures.
Examples of useful diamines of this type include bis-2-aminoethyl ether, N,N-dimethylethylenediamine, piperazine, and ethylenedia",ine. Examples of useful triamines of this type include N-aminoethyl pipe, d~il ,e, and dialkylene triamines such as diethylenetriamine, and dipropylenetriamine.
Preparation of these add~ lots, as well as a more complete description of the ~ddl ~ctc themselves, can be found in U.S. Patent 4,310,593 (Grossj, issued January 12, 1982, and in Ross et al, J. Or~anic Chemistrv, Vol. 29, pp. 824-826 (1964). Both of these documents are incorporated by rerere"ce.
Polymeric amines such as polyethyleneimines can also be used as the amino cG,npound for forming the adduct. A particularly desirable amino compound which can be reacted with epichlorohydrin to form prerer,ed cationic polymeric adduct resins useful herein co"~p~ise certain polyamide-20 polyamines derived from polyalkylene polyamines and saturated C3-C10 dibasic carl.oxylic acids. Epicl,lorol,ydrin/polyamide-polyamine ~ducts of this kind are water-soluble, tl,el"~oselli"g cationic polymers which are well known in the art as wet ~ , Iyl h resins for paper products.
In the prepardlion of polyamide-polyar,~ines used to form this 25 prefe"ed class of cationic polymeric resins, a dicalbo~tylic acid is first ~eac~ed with a polyalkylene-polyamine, preferably in ~lueo~ Is solution, under conditions such as to produce a water-soluble, long chain polyamide ~nlai"ing the recurring groups -NH(CnH2nHN)X-CORCO- where n and x are each 2 or more and R is the C1 to Cg alkylene group of the dic~lboxylic 30 acid.
A variety of polyalkylene polyamines including polyethylene polyamines, polypropylene polyamines, polybutylene polyamines and so on can be employed to ,urepare the polyamide-polyamine, of which the polyethylene polyamines represent an economically ~refel,ed class. More 35 specifically, ,c,refened polyalkylene polyamines used to yre,udre the cationic polymeric resins herein are polyamines containing two primary amine CA 0220~917 1997-0~-22 groups and at least one secondary amine group in which the nitrogen atoms are linked together by groups of the formula -CnH2n- where n is a small integer greater than unity and the number of such groups in the molecule ranges from two up to about eight and ~l~referably up to about four. The 5 nitrogen atoms can be attached to ~~cent carbon atoms in the group -CnH2n- or to carbon atoms further apart, but not to the same carbon atom.
Also contel"plated is the use of such polyamines as diethylenetriamine, triethylenetel~ ~" ~ine, tetraethylenepenla~ ~ ~ine, dipropylenetriamine, and the like, which can be obtained in reasonably pure form. Of all the foregoing, 10 the most prererled are the polyethylene polyamines containing from two to four ethylene groups, two primary amine groups, and from one to three secondary amine groups.
Also contemplated for use herein are polyamine precursor materials containing at least three amino groups with at least one of these groups 15 being a tertiary amino group. Suitable polyamines of this type include methyl bis(3-aminopropyl)amine, methyl bis(2-ar"il ,o~ yl)amine, N-(2-aminoethyl)piperazine, 4,7-cli",eli"/ltriethylenetet(d",i"e and the like.
The dicarboxylic acids which can be reacted with the foregoing polyamines to form the polyamide-polyamine precursors of the prefer,ed 20 cationic polymeric resins useful herein ,i~referably comprise the saturated aliphatic C3-C10 dicarboxylic acids. More ~urefer,ed are those containing from 3 to 8 carbon atoms, such as malonic, succinic, glutaric, adipic, and so on, together with diglycolic acid. Of these, diglycolic acid and the saturated aliphatic dicdl L,oxylic acids having from 4 to 6 carbon atoms in the 25 molecule, namely, succinic, glutaric and adipic are most ~,re~r,~:d. Blends of two or more of these dic~r~oxylic acids can also be used, as well as blends of one or more of these with higher saturated aliphatic dicalL,oxylic acids such as azelaic and sebacic, as long as the resulting long chain polyamide-polyamine is water-soluble or at least water-dispersible.
The polyamide-polyamine materials prepared from the foregoing polyamines and dicalL,oxylic acids are reacted with epichlorohydrin to form the cationic polymeric amino-epichlorohydrin resins. Preparation of such materials is described in greater detail in U.S. Patent 2,926,116 (Keim), issued February 23, 1960, U.S. Patent 2,926,154 (Keim), issued February 23, 1960, and U.S. Patent 3,332,901 (Keim), issued July 25, 1967, all of which are i,-co"uorated by rer~, el ,ce.

_ _ _ ~

CA 0220~9l7 l997-0~-22 The cationic polyamide-polyamine-epichlorohydrin resins preferled for use herein as the bonding agent are commercially marketed by Hercules Inc. under the trade name Kymene~). Especially useful are Kymene~
557H Kymene~) 557LX and Kymene~g) 557 Plus which are the 5 epichlorohydrin ~ cts of polyamide-polyamines which are the reaction products of diethylenetriamine and adipic acid. They are typically marketed in the form of ~ eo~s solutions of the cationic resin material containing from about 10% to about 33% by weight of the resin active.
The dicdrboxylic acid which can be reacted with the foregoing 10 polyamines to form the polyamide-polyamine precursors of the prefer,ed cationic polymeric resins useful herein may alternatively be unsaturated.
Typically the unsaturated dicarboxylic acids suitable for use herein will be selected from C4- C10 dicdl~oxylic acids. For example the dicarboxylic acid may be selected from itaconic acid cill~collic acid mesaconic acid 1 ~ maleic acid fumaric acid! and mixtures thereof.
The amino cor"pound that can be reac~ed with epichlorol,ydrin to form a cationic polymeric adduct resin useful herein may alternatively co",~rise polyamide-polyamines derived from polyalkylene polyamines and saturated or unsaturated C4 - C10 l,iL,asic carboxylic acids. Suitable 20 tri~,6Oxylic acids include for exam,ule citric acid and aconitic acid.
Additional t~nding agents suitable for use herein are described in U.S. Patent 3 901 236 issued to Assa,as~" et al. on August 26 1975; U.S.
Patent 5 002 814 issued to Knack et al. on March 26 1991; and U.S. Patent ~ 230 959 issued to Young Sr. et al. on July 27 1993. Each of these 25 pdlel ll::~ are i"~, ~urdled herein by refere, lce.
In general the col",l~osiles of the ~resent invention that employ a bGIldil)y agent can be ,~ uared in the following manner. The bonding agent is applied to the fibers which fibers may or may not be individ~ i7ed as des~,ibed herein. The flbers which are thus treated with the bolldirl~
30 agent are then physically ~ssoci~ted with the AGM particles so as to enable the chemically ~lirre"ed cellulosic fibers to wrap around the AGM and to allow ~-11,esion of the fibers and AGM. External forces are applied in order to ensure wrapping of the AGM by the fibers. Depel,di"g on the particular ~"di. ,y agent which is selected adhesion may occur without any additional 35 steps or may require an additional drying step or rea~io,l step. The adhesion step is followed by a mechanical treatment step if necess~ry~ to CA 0220~917 1997-0~ 22 WO 96/17S73 P~T/US95/15789 substantially separate the fibers wrapping a given AGM particle from the fibers wrapping other AGM particles.
The chemically stiffened, cellulosic fibers are typically individualized prior to application of the bonding agent. As used herein, "individualized"
5 means that the fibers are mechanically separated (i.e. "dt:riL,rdleu ) such that there is a relatively low level of fiber entanglement, as compared to a bulk fiber source such as a fiber sheet or bale. This mechanical derib, dliOn can be performed by a variety of methods which are presently known in the art or which may hereafter become known. Mechanical defibratioh is 10 preferably performed by a method wherein knot formation and fiber da"~age are minimized. One type of device which has been found to be particularly useful for deribraling the chemically stiffened fibers is the three stage fluffing device described in U.S. Patent 3,987,968, issued to Moore et al. ~n October 26, 1976, said patent being incorporated herein by rerer~"ce. The 15 fluffing device described in U.S. Patent 3,987,968 subjects a fibrous material to a combination of mechanical impact, mecl,a"ical agitation, air agitation and a limited amount of air drying to create a sub~lanLially knot-free fluff. Other applicable methods for derib,-ali"g the fibers include, but are not limited to, treatment with a Waring blender and tanyel ,lially 20 contacting the fibers with a rotating disk refiner or wire brush. Preferably, an air stream is directed toward the fibers being deribraled to aid in separdli"g the fibers.
The bGIldill9 agent may be applied to the fibers by any method for applying soh ~tions to materials, including coating, dumping, pouring, 25 dropping, spraying, atomizing, con.~e"sing, or immersing the fibers. As used herein, the term "applied" means that at least a portion of the surface area of at least some of the fibers has an effective amount of the bonding agent on it to cause adherence of the fibers and the AGM. In other words, the bonding agent can be applied onto a portion of the surface, or onto the 30 entire surface, of some or all of the fibers. Pl~:rerably, the bonding agent is coated onto the entire surface of most, preferably all, of the fibers so as to enhance the efficiency, sl,enylll~ and density of the bonds between the AGM particles and the fibers. In a preferred embod,",ent, the bonding agent is applied to a web of the fibers.
The bol1ding agent is preferaLly applied to the fibers in an amount of from about 0.10% to about 25% of the weight of the fibers in the composite, , _ _ _ _ _ _ CA 0220~917 1997-0~-22 ~1 the weight of the fibers being on a bone dry basis. More preferably, the bonding agent is used in an amount of about 10% to about 15% of the weight of the fibers in the composite, the weight of the fibers being on a bone dry basis. As used herein, "bone dry basis" means the actual weight 5 of the fibers less the weight of any moisture or other volatiles which may be present in the fibers. For example, a 100 9 sample of fibers containing 10%
moisture has a fiber weight, on a bone dr,v basis, of 90 9.
Where the bonding agent includes water, care must be taken to avoid e~cessive swelling of the fibers. Excessive swelling of the fibers is 10 evidenced by a significant loss in fiber curl. Without i"l~ndi, Iy to be limited by theory, it is believed that when such swelling occurs, the fiber surfaces become relatively round as colllpared to a s~hsPntially flat surface in the unswollen condition. As a result, the bonding area between any individual fiber and any individual AGM particle tends to decrease as the fibers swell 15 such that the degree of attach",e"L is lessened. Swelling of the fibers is influenced by the amount of water that is applied to the fibers and the amount of time that the fibers are exposed to the water. Control of these conditions so as to avoid excessive fiber swelling will be readily under~loo~
by one skilled in the art. Typically, the contact time between the fibers and 20 the aqueous bonding agent is kept to a very short time, e.g., from about a five minutes to a few seconds, by the addition of heat to dry or cure the rnixture. The mixture is typically subjected to te",peralures of about 100~C
to about 177~C, ,~3rt:f~lably from about 121~C to about 177~C, for this purpose.
2~ After applying the bo, Idil lg agent onto the fibers and while the bondi"y agent is still in liquid form, the particles and fibers are physically ~ssoci '.ed toyelher such that at a s~ sl~,Lial number of the chemically slirrened, cellulosic fibers wrap around the individual particles and are able to aJI ,ere to the particles. Thus, the AGM particles and fibers are brought 30 together and contacted in a manner which allows wrapping of the particles to occur by the fibers, and remain in contact with each other as component parts at at least the point where adherence of the fibers and AGM occurs.
The physical association of the AGM particles and fibers preferably involves physically co"ta-;~i"y the fibers and the AGM at at least a portion of 3~ the surface of the fibers having the bonding agent applied thereto.

CA 0220~917 1997-0~ 22 WO 96117S73 ~ 5/15789 The fibers and AGM particles are physically ~ssoci~led with the AGM particles being in substantially individual form. By "subslar,lially individual form" it is meant that s~ st~nlially all, preferably all, of the AGM
particles are not in physical contact with another AGM particle. Thus, the 5 AGM particles are sul.sta"lially non-agglomerated or non-aggregated.
Prt:re~ably, at least about 80%, more preferably at least about 90%, of the AGM particles are not in physical contact with another AGM particle.
The AGM particles and chemically ~lirre"ed, cellulosic fibers may be physically ~ssoci~ted in a number of dirrerer,t ways in order to cause a 10 suhstarltial number of the fibers to wrap around the particles. For example, the fibers and AGM can be physically ~ssoci~ed in the presence of external forces which function to draw the fibers around the individual AGM
particles, e.g., pressure, vacuum, electrostatic, impact, or impingement forces. Thus, the particles and fibers may be physically ~ssociated by 15 allowing the particles to rest adjace"~ the treated fibers, for example on a web of the treated fibers, with the addition of one or more of such exler"al forces to draw the fibers around the individual AGM pallicles. External forces of pressure may be applied, for example, by a co",pa~;tion (i.e., calendar) roll(s). Impact or impingement forces may be applied by mixing 20 the treated fibers and AGM particles together. Any suitable method for mixing the treated fibers and AGM may be used. For example, the fibers and particles may be air entrained, or impeller or propeller blended.
While the AGM particles and fibers are physically associated together, the bonding agent is dried or rea-;led so as to cause adherence 25 between the particles and the fibers. Depending on the chemical co""~osilio" of the particular bonding agent, AGM, and fiber material that is selected, reaction of the bonding agent may involve reaction of the bonding agent itself, for example polymerization, or reaction of the bonding agent with the polymeric material of the AGM, with the fibers, or both.
Depending on the particular bGndill9 agent being used, the drying andfor reacting may occur without any addilional step or may involve thermal heating andlor irradiation (e.g., ultraviolet, gamma-, or x-radiation).
The particular conditions required to dry and/or react the bonding agent will depe"d on the chemical composition of the particular bonding agent, AGM, and fiber material that is selected. Typically, the drying or reaction is sed by heating to a temperature of from about 100~C to about 177~C, _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ CA 0220~917 1997-0~-22 ,~.rererdblyfrom about 121~C to about 177~C, for a time period of from about a few seconds to about 5 minutes.
The resultant composition including the fiber-wrapped AGM particles ~ may require mechanical l~eal~nenl to separate the fibers wrapping a given 5 AGM particle from fibers wrapping other AGM particles (i.e., defibrdlion) so as to obtain the abso~bent co",,,~osiles of the present invention. Such dt:rit~,alion will typically be required where the fiber-wrapping of the AGM
particles is c~sed by the application of pressure, vacuum, or elect,osldlic forces, for example, where a compaction roll is used to cause fiber 10 wrapping. Where such forces have been applied, the fibers of the resultant composition are s-~hsPrltially uniformly entangled with other fibers in the co",l osilio,l so as to form a snhsl~,lially homogeneous, relatively high density mass. By subjecting such a mass to mechanical treatment, t~e fibers wrapping a given AGM particle are s~ sl~nlially separated from the 15 fibe!s wrapping other AGM particles to form the absorbe"l co",~osiles of the present invention. By "sl ~st~. ,lially sepa, ated," it is meant that there is a relatively low level of physical or chemical LGIId;llY between the fibers wrapping a given AGM particle and fibers wrapping other AGM particles.
P~ererably, less than about 50% of the number of fibers w,dp~ing a given 20 particle are bonded with the fibers wrapping other AGM particles. More preferably, less than about 25% of the number of fibers wrapping a given particle are bonded with the fibers wrapping other AGM particles. Most prererably, less than about 10% of the number of fibers \hl~,.Jpi..g a given particle are bonded with the fibers w~ ing other AGM particles. The 25 absorbent cG",posiles thus consisl essentially of individual AGM particles ("cores") w,~pped by the chemically stiflened, cellulosic fibers, with the deg,ee of fiber bonding tending to be greatest in the vicinity of the particle surfaces and to dil~illisl, with increasing distance from the surface of a given particle. The absG,l.e,)l composites have a lower density than the 30 mass prior to me~l,a-,ical lredl,nent. The co,nposiles typically have a density of from about 0.02 glcc to about 0.06 glcc, generally about 0.05 glcc. In addition, the tensile strength of the co""~osile, ignoring the tensile sLI~el ~!Jth of any given fiber in the composite, ap,c,roa~,l ,es zero.
The mechanical deril,ralion step may be performed by a variety of 35 methods as previously des~. iL,ed in rererence to individualizing the chemically slirr~ned, cellulosic fibers.

CA 0220~917 1997-0~-22 WO 96/17S73 PCI~/US95/15789 Where the treated fibers and AGM are physically associated by mixing, the need for defibration will depend on the conditions of mixing, including the conce~ a~ion of the fibers and AGM in the system and the shear of mixing. In general, the higher the conce"lralion or the lower the 5 shear, the more likely the need for a defibration step to provide the absorbent composites as herein described.
An economically preferred appardlus 20 for forming the composites of the present invention is shown in Figure 2. In general, Figure 2 shows a system for indivir~ali~ing chemically slirre"ed, cellulosic fibers, treating the10 fibers with a bonding agent, physically ~ssoci~ting AGM particles and the treated fibers, adhering the fibers to the AGM, and deribraling the resultant mass to form the composites of the present invention.
As shown in Figure 2, chemically stiffened, cellulosic fibers are taken from a bale, sheet, or other source of the stiffened fibers and optionally 15 other fibers (not shown) using a fiber opener 212, e.g., a picker type fiber opener such as available from the LaRoche Co"".any of Cours La Ville, France. The fiber opener 212 removes fibers from the bale in s~ ~hst~rltially individual form. As will be understood by one skilled in the art, some fiber nits or bundles may be prese, ll after passing through the fiber opener 212.
The fibers in s~hst~ntially individual form are l,dr,spo,led, e.g., by a first material handling fan 210a through a system of fiber lldnspo,l ducts multiply designated 214 in Fig. 2, to a reriberi~i"g appdralus 216. The material handling fan 210a, like the other material handling fans in the a,u~,d,alus 20, further opens the fibers and transports them to the next stage of the apparatus. A suitable material handling fan is available from No,ll,e", Blower Inc., Winnipeg, Manitoba, Canada, as Model LS WHL.
The refiberizing apparalus 216 further opens the fibers, i.e., it forms a lower density "fluf~' of the fibers and tends to individl~ii7e the fibers in any fibernits or bundles that may be present. A suitable refiberizing apparatus 216 for use herein is an Ospray Surge Bin, available from the Ospray Cor~oralio,l of Atlanta, GA.
The fibers are then transported, e.g., through fiber l,a,)sport ducts 214 by a second rnaterial handling fan 210b, to a fiber compaclir Ig appa,dlus 215. The fiber compacting appardll~s 215 functions to provide a subsla"lially uniform density to the fibers in opened form. The desired density will depend on the desired weight of fibers which is desired to be CA 0220~917 1997-0~-22 WO 96/17S73 PCT/US9~/15789 present in the final composite. The fiber compacting apparatus settings and indeed the need for this apparatus can be selected by one having ordinary skill in the art depending on the particular density which is desired. A
suitable fiber compacting apparatus 215 is a LaRoche Vertical Mat Former available from the LaRoche Company of Cours La Ville, France.
The fiber opener 212, material handling fans 21 Oa and 21 Ob, refiberizing apparatus 216, and compacting a,.paralus 215 serve to provide the fibers in a substantially homogeneous, opened form (i.e., the fibers are provided in a subst~ntially uniform density with a low level of nits or knots).
10 The specific apparatus employed to provide the fibers will depend on the weight and condition of fibers which is desired to be present in the final composite. It will typically be desired to at least partially deribrale the fibers, preferably to sl ~hst~ntially individll~li7e the fibers, in order to ens~re a low level of knots and nits and to ensure an even distribution of the 15 bonding agent on the fibers. The skilled artisan can select from the various defibrating and compacting devices such as are known or become known in the art to provide the fibers in the desired form.
The individualized, corr p~cted fibers are then transported, e.g., via a third material handling fan 210c through fiber transport ducts 214, to fiber 20 air-lay down forming a~Jpaldlii 218a and 218b such as are known in the art.
The fiber air-lay down apparatii 21 8a and 21 8b serve to form a substantially uniform, air-laid web of the fibers. A pr~r~r, ed fiber lay down apparal.ls 218 for use in the present invention is a Dan Web fiber lay down apparatus, available from Dan Web Air Forming Systems, Dan Web Forming 25 Inlel "alional, Ltd., Risskov, Del " "a, k. The Dan Web fiber lay down appar~l~Js is well known in the art to have a first, pe,roralecl roll and a second roll having picks or needles. The rolls rotate toward each other in the ",anner of conventional combining rolls. As the fibers pass from the fiber llallspGIl ducts 214 through the Dan Web appaldlLIs, the fibers are 30 further opened, i.e., the density of the "fluf~' is further decreased. The web of fibers can alternatively be prepared by other methods such as are known - or become known in the art, for example, wet-laying.
A bonding agent is applied to the fibers while in the air-laydown forming apparatii 218a and 218b. The bonding agent is provided by the 3~ bonding application station 222, which can be any a~aralus suitable for conveying the bonding agent to the air-laydown forming a~,paral.Js, for CA 0220~917 1997-0~-22 example, humidification chambers or spray chambers such as are known in the art. The air-laydown forming apparatus 218 serves to ensure even distribution of the bonding agent on the chemically stiffened, cellulosic fibers.
The fibers having bonding agent applied thereon are laid down by the first fiber lay down apparatii 218a onto conveyor 220 to form a web 217 of the fibers on the conveyor 220. The conveyor 220 can be any as are known in the art of web fo""dlion, for example a vacuum conveyor or an electrostatic conveyor.
As shown in Figure 2, an AGM disperser 224 is situated intermediate the air laydown forming apparatii 218a and 218b. The AGM disperser 224 deposits particles of AGM onto the fiber web 217 formed by the first air-laydown forming apparal~s 218a. The AGM disperser 224 dispenses t~e AGM particles in substa"Lially individual form onto the web 217. The AGM
disperser 224 can be any of the apparatus as are known in the art of particle deposition. For example, a Nordson AGM Disperser, available from the Nordson Corporation of Duluth, Georgia, is suitable for use herein.
The fiber web 217 having AGM particles deposited thereon then passes by the second air-laydown forming app2rdlus 218b where a second layer of chemically stiffened, cellulosic fibers having bonding agent distributed ll,ereon is deposited ~lj~cent the layer of AGM particles, to thereby form a trilayer web 219 of the two fiber webs having bonding agent distributed thereon and AGM particles deposited therebetween.
Means for agitating the trilayer web during its fo""dlion (not shown) may be employed to assist in keeping the fibers relatively open. For example, beater bars such as are known in the art may be positioned along the conveyor 220, which beater bars vibrate the web components.
The trilayer web 219 then moves through a set of calendar rolls 226.
The calendar rolls 226 combine and compact the fiber webs, thereby ensuring inli"~ale contact between the fibers, bonding agent, and AGM
particles, and wrapping of the fibers around the AGM particles.
As shown in Figure 2, the resultant cG",pacted web 227 is then transpo, Led through a drying station 228 by a drying conveyor 230. In the drying station 228, the web 227 is subiected to conditions, typically elevated temperatures and/or vacuum, sufficient to dry or cure the bonding agent.

CA 0220~917 1997-0~-22 WO 96/17573 1 ~ illS789 The drying station 228 can be any apparatus which is capable of ,l~el fl~r",ing - this function, for example any oven such as are known in the art. A
.refer~ ed type of drying station is a through-air drying oven, for example, as is available from ASEA Brown Boveri of Knoxville, TN.
From the drying station 228, the web 227 is transported to another fiber opener 212. The fiber opener can be any type suitable for opening the fibers, e.g., a fan type (impaction) or picker type. P,~ferably, the fiber opener 212 is a picker type. The fiber opener 212 opens the web, sl-hst~ntially separating the fibers which have the AGM particles adhered thereto, to form the absorbent composites of the present invention (it is to be understood that any means that is suitable for separating the fibers after the drying station, to thereby form the absorbent composites herein, may be employed). Thus, substantially individual units co",prised of s~ la"lia~ly individual AGM particles wrapped by chemically ~lir~"ed, cellulosic fibers are formed. (By "substantially individual units," it is meant that the fibers wrapping one AGM particle are substantially separaled from other fibers wrapping other AGM particles as previously described, so as to form relatively discrete units of AGM wrapped by fibers. It should be under:,~ood that some fiber bonding may occur between fibers wrapped around dirfere,1l AGM particles.) The material is prererably then transported, for example, through another material handling fan (not shown), which further separates the fibers having the AGM p~llicles a.Jl,e~ed thereto. From the material handling fan, the composites may be collected, for example, into a bale or container (not shown).
Altematively, the web 227 can be wound into a roll. The web 227 can be unwound and p~ssed through a fiber opener and preferably a rnaterial handling fan, as described above, at a later time to form the composites of the present invention. In either case, the absorbent composites may be used directly in an in-line process, or collected for later use.
In an alternative embodiment, preparation of the absorbent co"".osile involves the for",alion of a web of the chemically stiffened, cellulosic fibers, for example by air-laying or other suitable method, followed by application of the bonding agent to the web, followed by deposition of the AGM particles on the web and compaction of the web and particles to cause fiber wrapping of the particles. The composite according to this CA 0220~917 1997-0~ 22 WO 96tl7S73 PCT/US95/15789 embodiment can be formed using an apparatus subsl~"lially as shown in Figure 2, but wherein only one bonding application station is needed and is positioned between the first air-laydown forming apparatus and the AGM
disperser such that the fiber web is formed prior to application of the 5 bonding agent, followed by deposition of the AGM particles onto the web.
The fiber web having bonding agent and AGM particles deposited thereon then moves through the calendar rolls, which cause fiber wrapping of the particles, a drying station, and a fiber opener as previously described in relation to Figure 2 to foFm the absorbent composites of the present 10 invention. The composites are preferably p~ssed through a material handling fan as previously described in relation to Figure 2.
In yet another embodi",e,lt, two or more webs of fibers are formed, followed by the application of bonding agent to the webs and deposition of AGM particles thereon, followed by the combination of the webs, for 15 example, by using combining rolls such as are well known in the art. The combined webs are compacted together prior to the drying station to cause fiber wrapping of the particles, using, for example, a set of calendar rolls.
The comr~cted webs then move through the drying station and fiber opener as previously described in relation to Fig. 2 to form the absorbent 20 composites of the present invention. The co",posites are preferdbly passed through a material handling fan as previously described in relation to Fig. 2.
It will be uncle,~lood by the skilled artisan that any number of fiber webs and AGM layers can be combined in the foregoing manner, and consislent with the teachings herein, to form the absorbent composites of 25 the present invention. The composites of the present invention can also be formed by several alternative methods. Suitable al~er~,ali~/e methods are disclos~d in the above-~fere~ced U.S. Patents 3,901,236; 5,002,814; and 5,230,959.
In one alternative method of the present invention, the co~posile is 30 formed by mixing the AGM particles with the fibers which have been treated with the bonding agent. Mixing can be c~' ~sed, for example, by the use of any stirring equi~cment such as known in the art, or by air entrainment.
Suitable mixing procedures are described, for example, in the above-rererenced U.S. Patents 3,901,236; 5,002,814; and 5,230,959. Mixing 35 c~l~ses the fibers to wrap around the AGM particles. Bonding is then ca~sed as described herein, for example, by drying the mixture and/or CA 0220~917 1997-0~-22 WO 96/17~;73 PCTIUS95/15789 allowing or causing the bonding agent to react with the fibers and particles.
The composite is preferably dried, either while or after bonding occurs.
Drying may be achieved by any suitable method, for example, by applying heat or by subjecting the cG"~,uosite to infra-red radiation.
The resultant composite contains chemically stiffened fibers wrapped around and adhered to the AGM particles. An abso~L,enl composite 10 of the present invention, made by a process desc~ ibed in the above-.~rere,1ced U.S. Patent 5,002,814, is shown in Figure 1, which is a Scanning Electron Micrograph of the absorbent composite taken at a magnification of 85X. As shown and previously described, the composites are sl ~hst~ntially individual units comprised of substantially individual AGM
particles ("cores") wrapped by chemically stiffened, cellulosic fibers.
Due to the relatively large diameter or cross-section of the A~M
particles relative to the fibers, the fibers are in effect adhered to the AGM
particles in the resultant composite. The individual fibers are substantially unbonded except to the AGM particles. Similarly, the individual AGM
particles are substantially unbonded except to the fibers.
At least a portion of s~ ,lially all, preferably all, of the chemically slirre"ed, cellulosic fibers are disposed on or near at least a portion of the surface of the individual particles of absorbent gelling material. The fibers are disposed such that at least one fiber end, prererdbly both fiber ends, protrudes from the surface of the particles. Without intending to be bound by theory, it is believed that protrusion of the fiber ~-csist.C in minimizing miyldliol) of the co""~osile in absGrbenl articles incorporating the composite. The fibers wrapped around a given AGM particle are suL~slal ,lially Sepdl dled from the fibers wrapped around other AGM
~al licles, as previously des~;, iL; ed.
The a~sor~enl colnposiles of the present invention are particularly useful in absorbent members for disposable absorl,enl articles. It should be understood, however, that the composites and absorbenl members containing the same can be used for many purposes in many other fields of use. For example, the absorbent composites of the present invention can be used for packing containers, drug delivery devices, wound cleaning devices, burn l, edl" ,el ~l devices, ion excl~ange column materials, construction materials, agricultural or horticultural materials such as seed sheets or water-retentive materials, and industrial uses such as sludge or CA 0220~917 1997-0~-22 WO 96/17S73 PCI'/US95/15789 oil dewatering agents, materials for the prevention of dew fo""~Lion, desiccants, and humidity control materials.
As used herein, the term "absorbent article" refers to devices which absorb and contain body exud~tes, and more specifically, refers to devices 5 which are placed against the skin of a wearer to absorb and contain the various exudates discharged from the body. The term "disposable" is used herein to describe absorbent articles which are not intended to be laundered or otherwise restored or reused as an absorbent article after a single use. Examples of disposable absorbent articles include feminine 10 hygiene garments such as sanitary napkins and panti-liners, diapers, incontinence briefs, diaper holders, training pants, and the like.
Dispos~hle absorbent articles typically CG~prise a liquid pervious topsheet, a liquid impervious backsheet joined to the topsheet and an absorbe, ll core positioned between the topsheet and the backsheet.
15 Dis~ osable abso~L~ent articles and co"lpo"ents thereof, including the topsheet, backsheet, absorbent core, and any individual layers of these components, have a body surface and a garment surface. As used herein, "body surface" means that surface of the article or component which is intended to be worn toward or ~ cel,t to the body of the wearer, while the 20 "garment surface" is on the opposite side and is intended to be worn toward or placed ~d; ~c-ent to the wearer's body or un.Jergdr" ,ents when the disposable absorbent article is worn.
The composites of the present invention are particularly useful for use in the absorbe,)l core of disposa~le absGrl,e"l articles. In general, the 25 con,posiles may be used in the same manner for which conventional absG,bel,t gelling materials have been used, for example, in laminates, in relatively high density cores (i.e., com~ 1ed, calendared, densified, etc.
cores), or in relatively low density cores (i.e., not compacted, for example, air-laid cores). However, the absorber,l composite provides certain 30 advantages over conventional particulate abso~ belll materials. In particular, the ~L,sor~e,ll composite has a reduced tendency to migrate within and/or out of the abso,bent article, and a red~ced tendency to cause pinholing. With conventional partic~ te absorbent materials, heavy calelldali"g is typically required in order to minimize migration of the 35 particles. As a result, the potential absor,~,lion capacil~ and absGr,uliGll rate of the absorL,enL core, based on the theoretical absorption capacities and _ _ _ _ _ _ _ _ _ _ _ CA 0220~917 1997-0~-22 WO 96/17573 PCTIUS9~/15789 rates of the components of the absorbent core, is not realized. In addition, - the calendared absorbent core tends to be stiff or ~boardy," and pinholing is more likely to occur. Moreover, the particulate material may still migrate within and/or out of the absorbent article. Therefore, a secondary topsheet 5 is often included to minimize the IJotenlial for gel on skin and/or to increase the wearer's colllro,l. In colllldsl, the absorbent composites of the present invention have a lesser tendency to migrate within and out of the absorbent core. Therefore, absorbent cores containing the absorbent composites of the present invention may not require heavy calendaring to minimize 10 migration of the particles of absG,benl gelling material. The uncalendared absorbent core tends to have a uniform, relatively low fiber density, i.e., the core has a relatively open structure. Thus, the uncalendared core tends to have better fluid acquisition properties (e.g., rate and quantity of fluid absorbed in a given time period) than a calendared core. Such cores also 15 tend to be more cGn~r" ,able than cale"dared cores containing conventional AGM. The need for a secondd~y topsheet is Illillillli~ed since migration is minimized and since the particles of AGM are cushioned by the fibers. In addition, the problem of pinholing associated with calendaring may be avoided.
The following description generally discusses the absorbent core, topsheet, and backsheet materials that are useful in disposable absorbent articles. It is to be un-lerslood that this yeneral desc, i,ulion applies to these col"pul,ents of the specific absorbent articles shown in Figures 3-5 and further described below, in addition to those of other disposable absorbent articles which are yenerally desc, ibed herein.
The absorbent core comprises the absorbent composite of the ,c,resenl invention. The absorbent core contains at least one absorbent member that includes the col"posile. As used herein, ''absûrbenl member"
means an aL,sorL,ent structure that is capable of transporting liquids between its structural elements. The term "structural elel"enls" as used herein refers to the individual absorbent composites of the present invention and other materials which may comprise the absorbent structure, for example, fibers, yarns, strands, loose particles, and the like. As used herein, the term "structure" includes the term "structures" and the terms "layer", "layers", and "layered". An absorbent member is not necess~rily limited to a web or the like in the form of a single layer or sheet of material.

CA 0220~917 1997-0~-22 The absorbent member may actually comprise laminates, webs, or combinations of several sheets or webs of the types of the absorbent materials herein described.
The absorbent member can consist essentially of the absorbent 5 composite of the present invention, for example, a web of the con,posile.
Alternatively, the absorbent members of the present invention may contain other materials, for example, absorbent materials that are commonly used in disposable absorbent articles such as the materials described below. In a preferred embodiment, the absorbent member contains the absorbent 10 composite and a carrier means for the composite. The carrier means is a structure or matrix that the absorbent composite may be located or dispersed in, or on. The carrier means preferably contains an absorbent material, more preferably hydrophilic fibers, such as those described herein. The absorbent composite may be sub:,lanlially homogeneously 1~ (uniformly) dispersed throughout the carrier means or a portion of the carrier means. Aller"ali,/ely, the absorbent composite may be dispersed in various weight ratios throughout different regions and throughout the thickness of the carrier means. In yet another alternative embodiment, the absorbent composite may be distributed in regions or zones which have 20 higher conce"l,dlions of the absorbent composite than do other regions or zones of the carrier means.
The absorbent members of the present invention can be formed by any process or technique that provides an integral absorbent structure. For example, the absorbent members can be formed by a process or technique 25 that provides a web of the absorbent composite or a web comprising a combination of the absorbent composite and fiber material (in the case of a fibrous carrier means). Suitable processes include particle deposition processes, wet-laying and air-laying. The al,sorb~, ll members are prererably formed by air-laying the absorbent composite, the fiber materials, 30 or a mixture thereof so as to form a structure consisting essentially of the absorbent composite, or a structure having the absorbent composite located or dispersed in, or on the fibers. A procedure for air-laying a mixture of fibers and superabsorbent hydrogel-forming material particles which can be readily adapted by the skilled artisan for use herein is described more fully 3~ in U.S. Patent 4,610,678, entitled "High-Density Absorbent Structures"
issued to Weisman et al. on September 9, 1986, incorporated herein by CA 0220~917 1997-0~-22 reference. Several layers of the absorbent composite and a suitable carrier - means may be formed.
As will be understood by the skilled artisan, the degree of fiber ~ bonding between the fibers wrapping a given AGM particle and fibers 5 wlap~ y other AGM particles will depend on the degree of calendaring or embossing of the absorbent member, and the presence of components other than the absorbent composite in the member. For example, where an absorbent member consists essentially of a web of the absorLent composite and is calendared or emhossed, there may be a substantial amount of fiber 10 bonding between fibers wrapping dirrere,1t AGM particles in the embossed or calendared area. Where the absorbent composite is substantially homogeneously dispersed throughout a web containing hydrophilic fibers, the fibers wrapping a given AGM particle tend to remain subsLar,Lia~ly se~a, aled from fibers wrapping other particles. The amount of fiber 15 bonding tends to inGrease as the amount nf absorbent Gomposite in the web increases, or where the web is calendared or er,~l~osse~
In general, the absorbent core is capable of absorbing or retaining liquids (e.g., menses, urine, and/or other body exl~d~tes). The absorbent core is ,urerera~ly co" l~r~ssible, co"for" ,able, and non-irritating to the 20 wearer's skin. The absGrbe, ll core may be manufactured in a wide variety of sizes and shapes (e.g., rec~angular, oval, hourglass, 'T' shaped, dog bone, asymmetric, etc.). In addition to the absorbent composites of the present invention, the absorbent core may include any of a wide variety of liquid-absorbelll materials co""nG"ly used in absorbent articles, such as 25 co""ninuted wood pulp, which is gel,erdlly ,~fer,~:d to as airfelt. Examples of other suitable absorbent materials for use in the absorbent core include creped cellulose wadding; meltblown polymers including coform; chemically slirre"ed, modified or cross-linked cellulosic fibers; synthetic fibers such as crimped polyester fibers; peat moss; tissue including tissue wraps and 30 tissue laminates; absorbent foams; absorbent sponges; superabsorbent polymers; abso, L,enl gelling materials; or any equivalent material or combinations of materials, or mixtures of these. The configuration and construction of the absorbent core may also be varied (e.g., the absG~bent core may have varying caliper zones andlor have a profile so as to be 35 thicker in the center; hydrophilic gradients; gradients of the absorbent composite of the present invention, superabsorbent gradients; or lower CA 0220~917 1997-0~-22 average density and lower average basis weight zones e.g. acquisition zones; or may comprise one or more layers or structures). The total absorbent capacity of the absorbent core should however be compatible with the design loading and the intended use of the absorbent article.
5 Further the size and absorbent capacily of the absorbent core may be varied to acco~ lodate different uses such as diapers incontinence pads pantiliners regular sanitary napkins and overnight sanitary napkins and to acco",l"odate wearers ranging from infants to adults.
The absorbent core comprises at least one absorbent member 10 comprising the absorbent composite of the present invention. Thus the absorbent core may consist essenlially of the absorbent composite of the present invention. In a pr~ft:r,ed embodiment the absorbent core has at least one absorL,ent member which comprises the absorbent composite a~d a carrier means for the composite such as previously described. The 15 carrier means preferably comprises a fibrous web or batt that conldil)s entangled masses of hyclropl)ilic fibers. The aL,sorL,ent composite is prererably s~ Ihst~ntially homogeneously (uniformly) dispe, ~ed throughout the carrier means or a portion of the carrier means. The absorbent properties of such atiSGI L,ent member~ may thus be generally uniform 20 throughout the ",e",ber. Aller"dli~/ely the absorL,enl composite and hydrophilic fibers can be dispersed so as to form gradients or zones of differential aL,sor~tion capacily and/or rate in the absorbent member. The absorbent member may be calendared or embossed.
As used herein the term "hydrophilic" describes fibers or the surfaces 25 of fibers which are wetted by the liquids deposited onto the fibers. As ~isc~ssecl in detail in The American Chemical Society publication entitled Contact An~le. WetabilitY. and Adhesion edited by Robert F. Gould and copy,iyl,ted in 1964 a fiber or surface of a fiber is said to be wetted by a liquid either when the cGIllac;t angle between the liquid and the fiber or 30 surface is less than 90~ or when the liquid will tend to spread spontaneously across the surface of the fiber; both conditions normally coexisting.
Any type of hydrophilic fibrous material which is suitable for use in conventional absorbent products are suitable for use in the absorbent core herein. Specific examples of such hydrophilic fibrous materials include 3~ cellulose fibers modified cellulose fibers chemically ~lirrened cellulose fibers such as those desc~ ibed herein for forming the absorL en~ composite of CA 0220~917 1997-0~-22 the present invention, rayon, polyester fibers such as polyethylene terephthalate (DACRON), hydrophilic nylon (HYDROFIL), polymeric bicomponent fibers, and the like. Other examples of suitable hydrophilic fibrous materials include hydrophilized hyd~ upi ,obic fibers, such as sur~actant-treated or silica-treated thermoplastic fibers derived, for example, from polyolefins such as polyethylene or polypropylene, polyacrylics, polyamides, polystyrenes, polyurethanes and the like. For reasons of availability and cost, cellulose fibers, in particular co"""i"uted wood pulp (i.e., airfelt), are prefer,ed for use in the absorbent core, particularly the ~lurage layer described herein.
The amount of composite included in the absorbent core is generally selected based on the amount of absorbent gelling material that is desired in the article, which is itself generally selected based on the absorptive capacity and absorptive rate that is desired in the article. The relative amount of absorbent gelling n,alerial and hydrophilic fibers used in absorbent members can be most conveniently expressed in terms of a weight perue"lage of the absorbent member. Typically, absorbent gelling materials are used with hydrophilic fibers in an amount ranging from about 2% to about 90%, preferably about 30% to about 85%, more pr~ferably about 30% to about 70%, most prererably from about 40% to about 70%, AGM and correspondingly, about 10% to about 98%, preferably from about 70% to about 15%, more prerer~l~ly from about 70% to about 30%, most preferably from about 60% to about 30%, hydrophilic fibers. The relative amounts of the abso,L,ent co",,,~osile and any hydrophilic fibers (including those making up the composite) can be selected to achieve these ranges.
In order to minimize the thicl~l ~ess of the absorbent article, it may be desired to " ,~i" ,ke the conce"l, dlion of AGM in certain absol L.enl members, particularly an absorbent member to be used for fluid sloraye.
The d~so,bent core can include other absorL,enl components that ~ 30 are often used in absorbent articles, for example, a dusting layer, a wicking or ~og~lisition layer, or a secGi)cJa~y topsheet for increasing the wearer's - cor,,rui l.
The topsheet is prererably compliant, so~t feeling, and non-irritating to the wearer's skin. Further, the topsheet is liquid pervious, permitting 35 liquids (e.g., menses and/or urine) to readily penetrate through its thic~rless. A suitable topsheet may be manufactured from a wide range of CA 0220~917 1997-0~-22 materials such as woven and nonwoven materials (e.g., a nonwoven web of fibers); polymeric materials such as apertured formed thermoplastic films, apertured plastic films, and hydroformed thermoplastic films; porous foams;
reticulated foams; reticulated thermoplastic films; and thermoplastic scrims.
Suitable woven and nonwoven materials can be comprised of natural fibers (e.g., wood or cotton fibers), synthetic fibers (e.g., polymeric fibers such as polyester, polypropylene, or polyethylene fibers) or from a combination of natural and synthetic fibers. When the topsheet comprises a nonwoven web, the web may be manufactured by a wide number of known techniques.
For example, the web may be spunbonded, carded, wet-laid, melt-blown, hydroentangled, combinations of the above, or the like.
The backsheet is impervious to liquids (e.g., menses and/or urine) and is prefer~bly manufactured from a thin plastic film, although other flexible liquid impervious materials may also be used. As used herein, the term "flexible" refers to materials which are compliant and will readily co"for", to the general shape and contours of the human body. The backsheet prevents the exud~tes absorbed and contained in the absorbent core from wetting articles which contact the absorber,t article such as bedsheets, pants, pajamas and u"derydr",ents. The backsheet may thus co" "~, ise a woven or nonwoven material, polymeric films such as thermoplastic films of polyethylene or polypropylene, or co",posile materials such as a film-coated nonwoven material. A suitable backsheet is a polyethylene film having a thickness of from about 0.012 mm (0.5 mil) to about 0.051 mm (2.0 mils). Exemplary polyethylene films are manufactured by Clopay CGr"oralion of Ci"ci""ali, Ohio, under the designdLion P18-0401 and by Tredegar Film Products of Terre Haute, Indiana, under the designation XP-39385. The backsheet is pr~ferably embossed and/or matte finished to provide a more clothlike appearance. Further, the backsheet may permit vapors to escape from the absorbent core (i.e., the backsheet is breathable) while still preventing ~Yucl~tes from passing through the backsheet. The size of the backsheet is dicPted by the size of the absorbent core and the exact absorbent article design selected.
The backsheet and the topsheet are positioned ~ ce"~ the garment surface and the body surface, respectively, of the absorbent core. The absor~e"t core is ,c,referably joined with the topsheet, the backsheet, or both in any manner as is known by attachment means (not shown in CA 0220~917 1997-0~-22 Figures 3-5) such as those well known in the art. However, embodiments of ~ the present invention are envisioned wherein portions of the entire absorbent core is unattached to either the topsheet, the backsheet, or both.
For example, the backsheet and/or the topsheet may be secured to 5 the absorbent core or to each other by a uniforrn continuous layer of adhesive, a patterned layer of adhesive, or an array of se,~arale lines, spirals, or spots of adhesive. Adhesives which have been found to be satisfactory are manufactured by H. B. Fuller Col I Ipdl Iy of St. Paul, Minnesota under the designation HL-1258 or H-2031. The attaol~ "t 10 means will ,~referably comprise an open pattern network of filaments of adhesive as is disclosed in U.S. Patent 4,573,986, issued to Minetola, et al., March 4, 1986, and which is incorporated herein by refere,lce. An exemplary attachment means of an open pattern network of filaments comprises several lines of adhesive filaments swirled into a spiral palLer~
15 such as illustrated by the apparalus and method shown in U.S. Patent 3,911,173 issued to Sprague, Jr. on October 7, 197~; U.S. Patent 4,785,996 issued to Zwieker, et al. on November 22, 1978; and U.S. Patent 4,842,666 issued to Werenicz on June 27, 1989. Each of these patents are incorporated herein by rerere"ce. All~",dli~/ely, the ~llac~""e"l means may 20 comprise heat bonds, pressure bonds, ulll dsonic bonds, dynamic mechanical bonds, or any other suitable dllaci ,r"e"l means or combinations of these dllaclllllenl means as are known in the art.
A ~ler~lled e,nbocli,nent of a unitary disposable absorbent article of the present invention is the catamenial pad, sa"ild,y napkin 30, shown in 2~ Figure 3. As used herein, the term "sanitary napkin" refers to an absorbent article which is worn by females ~15 ~celll to the pu-le"dal region, generally extemal to the urogenital region, and which is intended to absorb and co"tail, menstrual fluids and other vaginal discl,~rges from the wearer's body (e.g., blood, menses, and urine). Il,lerlabial devices which reside 30 partially within and partially exler"al of the wearer's vestibule are also within the scope of this invention. As used herein, the term "pudendal"
refers to the externally visible female genitalia. It should be u"~er~lood, however, that the ~resenl invention is also applicable to other feminine hygiene or catamenial pads such as pantiliners, or other absorbent articles 35 such as incontinence pads including diapers, and the like.

CA 0220~917 1997-0~-22 Figure 3 is a plan view of the sanitary napkin 30 of the present invention in its flat-out state with portions of the structure being cut-away tomore clearly show the construction of the sanilary napkin 30 and with the portion of the sanitary napkin 30 which faces or contacts the wearer, 5 oriented towards the viewer. The sanitary napkin 30 has two surfaces, a body-contacting surface 302 or "body surface" and a garment surface 304.
The sanitary napkin 30 is shown in Figure 3 as viewed from its body surface. The body surface is intended to be worn ~dj~cent to the body of the wearer while the gar"~e"t surface is on the opposite side and is 10 intended to be placed ~ cent to the wearer's underyd,,,,enls when the sanitary napkin 30 is worn. As shown in Figure 3, the sanitary napkin 30 preferably comprises a central absorbent body 310 and an undergarment protection system 350.
The central absorbent body 310 comprises a liquid pervious topsheet 320, a liquid impervious backsheet 330 joined with the topsheet 320, and an absorbent core 340 posilio"ed between the topsheet 320 and the backsheet 330. Figure 3 also shows that the central absorbent body 310 has a periphery which is defined by the outer edges of the central absorbent body 310 in which the longitudinal edges are desiy"aled 312 and the end edges are designated 314. The central absorbent body 310 further has a longitudinal centerline 316 and a transverse centerline 318. The term "longitudinal", as used herein, refers to a line, axis or direction in the planeof the aL,sor~ent article that is generally aligned with (e.g., approximately parallel to) a vertical plane which bisects a sl~"di"g or upright wearer into left and right body halves when the abso,bel,l article is worn. The terms "transverse" or "lateral" as used herein, are interchangeable, and refer to a line, axis or direction which lies within the plane of the absorbent article that is generally perpendicular to the longitudinal dil~;tioll. As shown in Figure 3, the absorbent core 340 has a body surface 342, a yd"nel,l surface 344, side edges 346, and end edges 348.
In general, the construction of the topsheet 320, backsheet 330, and absorbent core 340 is as described herein above. The topsheet, the backsheet, and the absorbent core may be assembled in a variety of well known configurations (including so called "tube" products), with the 35 absorbent core being adapted to include the absorbent composites of the present invention. P,e~"ed sanitary napkin configurations are described wo 96S175~3 PCT/US9~/lS789 generally in U.S. Patent 4,950,264, "Thin Flexible Sanitary Napkin" issued to Osborn on August 21 1990; U.S. Patent 4 425 130 "Compound Sanitary Napkin" issued to DesMarais on January 10 1984; U.S. Patent 4,321,924, "3Ordered Disposable Absorbent Article" issued to Ahr on March 30 1982;
U.S. Patent 4 589 876 "Shaped Sanitary Napkin With Flaps" issued to Van Tilburg on August 18, 1987, U.S. Patent 5,009,653 '~hin Flexible Sanitary Napkin" issued to Osborn on April 23 1991 and U.S. Patent 5 308 346 "Elasticized Sanitary Napkin" issued to Sneller et al. on May 3 1994.
Each of these ,caleills are hereby inco,uorated herein by referel,ce. Figure 10 3 shows a preferred er~bodiment of the sanitary napkin 30 in which the topsheet 320 and the backsheet 330 have length and width dimensions generally larger than those of the absorbent core 340. The topsheet 320 and the backsheet 330 extend beyond the edges of the absorbent core 34 to thereby form portions of the periphery.
Exemplary absorbent structures for use as the absorbent core in sanitary napkins and which can be adapted to the presenl invention are desoribed in the above referenced and incor,uolaled U.S. Patent 4 610 678 and in U.S. Patent 4 834 735 entitled "High Density Absorbent Members Having Lower Density and Lower Basis Weight Acquisition Zones" issued to Alemany et al. on May 30 1989; and European Patent Application No. 0 198 683 The Procter & Gamble Company published October 22 1986 in the name of Duenk et al. The abso,LJer,l cores des~, iL,ed in these patenls can be readily adapled to include the absGrl,e"t composites as an absorL,ei,l gelling material therein desc;,i~ed. A prefer,~d embodi"le,-l of the absorl,e"t core of the presel ,l invention comprises a layer of suyerdbso,L,ant ",dl~rial disposed between hNo air !aid tissues as described in the above rererenced and incor~ oraled U.S. Patent 4 9~0 264 and U.S.
Patent 5 009 653 wherein the superabsorbe, ll material includes the absorLe"( col"posiles of the ,cr~sellt invention. Each of these patents are i"wr~,o,aled herein by rererel,ce. The abso,L,ent core may alternatively con,p, ise a web comprising hydrophilic fibers and the absorbe"l composite as desc, ibed above in general reference to absorbent articles.
A ~Jreferled topsheet 320 for the sanitary napkin 30 comprises an apertured formed film. Apertured formed films are prer~rl ed for the topsheet bec~se they are pervious to body exudates and yet are non-absorbent and have a red~ced tendency to allow liquids to pass back CA 0220~917 1997-0~-22 WO 96/17S73 r~ 5lls789 through and rewet the wearer's skin. Thus the surface of the formed film which is in contact with the body remains dry thereby reducing body soiling and creating a more comro~lable feel for the wearer. Suitable for,ne~ films are described in U.S. Patent 3 929 135 entitled "Absor~.tive Structure 5 Having Tapered Capillaries" which issued to Tho"~pson on December 30 1975; U.S. Patent 4 324 246 entitled "Disposable Absorbent Article Having A Stain Resistant Topsheet" which issued to Mullane et al. on April 13 1982; U.S. Patent 4 342 314 entitled "Resilient Plastic Web Exhibiting Fiber-Like Properties" which issued to Radel et al. on August 3 1982; U.S.
Patent ~463045 entitled "Macroscopically Expanded Three-Dimensional Plastic Web Exhibiting Non-Glossy Visible Surface and Cloth-Like Tactile Impression" which issued to Ahr et al. on July 31 1984; and U.S. Patent 5006394 "Multilayer Polymeric Film" issued to Baird on April 9 1991.
Each of these patents are incorlJuraled herein by ,ererel)ce. The prefer,ed topsheet for the present invention is the formed film described in one or more of the above patents and marketed on sanitary napkins by The Procter & Gamble Co~ a~ ~y of Cincinnati Ohio as "DRI-WEAVE".
In a prererled embodillle,-t of the sanitary napkins 30 of present invention the body surface of the formed film topsheet 320 is hydrophilic so as to help liquid to transfer through the topsheet faster than if the body surface was not hydrophilic so as to diminish the likelihood that menstrual fluid will flow off the topsheet rather than flowing into and being absorbed by the absorbent core. In a ,ure~r,ed embodiment the topsheet can be made hydrophilic by treating it with a surfactant such as is des~;, ibed in the above referel,ced and i"cGr~,or~ted U.S. Patents 4 950 254 and 5 009 653.
In the piefer~ed ~",bocli",enl of the present invention shown in Figure 4 an ~cq~lisition component 360 (or coi~pone"ts) may either be positioned between the topsheet 320 and the absorbent core 340 or comprise the bottom surface of a cG,,,,uosite topsheet. The acquisition component may 30 serve several functions. These fu.l~io"s include improving wicking of exud~tes over and into the absorbent core. The improved wicking of exlld~tes is important because it provides a more even distribution of the exl-d~tes throughout the abso,L,e.ll core and allows the sanitary napkin 30 to be made relatively thin. (The wicking referred to herein may e. ,co",pass 35 the transpo,l~lion of liquids in one two or all directions (i.e. in the x-y plane and/or in the z-direction). The acquisition co,,,pur,e,ll 36û may be CA 0220~917 1997-0~-22 comprised of several di~ferent materials including nonwoven or woven webs of synthetic fibers including polyester polypropylene or polyethylene;
natural fibers including cotton or cellulose; blends of such fibers; or any equivalent materials or combinations of materials. Examples of sanitary napkins having an acquisition component are more fully described in the above referenced and i"cor~.oraled U.S. Patents 4 9~0 264 and 5 009 653;
and in PCT Patent Publication WO 93/11725 "Abso,Lenl Article Having Fused Layers" published in the name of Cree et al. on June 24 1993; and copending U.S. Patent Application Serial No. 08/289 084 filed May 6 1994 in the name of Cree et al. Each of these references is incorporated herein by reference. In a ,crerened embodiment the ~cguisition cor"~ o"ent 360 may be joined with the topsheet 320 by any of the conventional means for joining webs together most preferably by fusion bonds as is more full~
described in the above-l~rerellced Cree et al. patent application and PCT
1 5 publication.
In use the sanitary napkin 30 can be held in place by any attachment means 370 well-known for such purposes. rlererably the sanitary napkin is placed in the user's u"derga""ent or panty and secured thereto by a fastener such as an adhesive. The adhesive provides a means for securing the sanitary napkin in the crotch portion of the undergd""ent.
Thus a portion or all of the garment surface 304 of the sa"ild~y napkin 30 may be coated with adhesive. For the prefer~ed elllbodir~e~ of the present invention shown in Figure 3 a pollioll is disposed on both the central absorbent body 310 and the u"dergar",e"l prutection system 350 of the sa"ild,y napkin 30. That portion of the adhesive disposed on the central absorbent body is identified as the pad 5 Il:esivG 372 and that po~.ior disposed on the undergarlllent protection system is identified flap adhesive 374 depending on which element of the u~ er~a~ ent protec~ion system whereon the adhesive is disposed. Any adhesive or glue used in the art for such purposes can be used for the adhesive herein with pressure-sensitive adhesives being prefer~ ed. Suitable adhesives are Century A-305-lV
manufactured by the Century Adhesives Cor~oralion of Columbus Ohio;
and Instant Lock 34-2823 manufactured by the National Starch and Chemical Company of Bridgewater NJ. Suitable adhesive fasteners are a,so desc, ibed in U.S. Patent 4 917 697 issued to Osborn et al. on April 17 1990. The pressure-sensitive adhesive is typically covered with a removable release liner in order to keep the adhesive from adhering to a CA 0220~917 1997-0~-22 suRace other than the crotch portion of the undergarll~ent prior to use.
These are identified as the pad release liner 376 and the flap release liner 378 in Figure 4. Any commercially available release liners commonly used for such purposes can be utilized herein. Non-limiting examples of suitable 5 release liners are BL30MG-A Silox E1/0 and BL30MG-A Silox 4P/O both of which are manufactured by the Akrosil Corporation of Menasha Wl.
Suitable release liners are also described in the above-referel1ced U.S.
Patent 4 917 697. The sar~ilary napkin 30 of the present invention is used by removing the release liner and thereafter placing the sanitary napkin in 10 an undergarment so that the adhesive contacts the underydr",ent. The adhesive maintains the sar,ila~ y napkin in its position within the undergar",ent during use.
The sanitary napkin of the present invention may further co"",rise~n undergarment protection system 350 for example side flaps. The flaps 15 serve at least two purposes. First the flaps help serve to prevent soiling ofthe wearer's body and underwear by menstrual fluid pr~rerably by forming a double wall barrier along the edges of the underga~"ent. Second the flaps are preferably provided with a portion of the attacl""enl means 370 the flap adhesive 374 on their garment surface so that the flaps can be 20 folded back under the undergar")enl and attached to the garment facing side of the u"Jerljdr",ent or to each other. In this way the flaps serve to keep the sanitary napkin properly positioned in the ~ Je,y~r",ent. The flaps can be constructed of various r"alerials including "~alerials similar to the topsheet backsheet tissue or co",L,i ,alion of these materials. A
25 number of sa"ila,y napkins having flaps suitable or adaplable for use with the sanitary napkins of the present invention are disclosed in the above referenced and i,,c~r,uoraled U.S. Patent 4589876; and in U.S. Patent 4,687,478 entitled "Shaped Sanitary Napkin With Flaps" which issued to Van Tilburg on August 18, 1987 and U.S. Patent 4,608,047, entitled 30 "Sanitary Napkin Attachment Means" which issued to M~Jllillgly on August 26, 1986. Each of these patents are incorporated herein by reference.
Another disposable absorbent article in which the absorbent composites herein may be used are diapers. As used herein the term "diaper" refers to an absorbent article generally worn by infants and 35 i"co,llir,ent persons that is worn about the lower torso of the wearer.

CA 0220~917 1997-0~-22 WO 96/17S73 PCI~/US95/15789 '43 Figure 5 is a plan view of the diaper 50 of the present invention in its flat-out uncontracted state (i.e. with elastic induced contraction pulled out) with portions of the structure being cut-away to more clearly show the construction of the diaper 50 and with the portion of the diaper 50 which faces away from the wearer the outer surface oriented towards the viewer.
As shown in Figure 5, the diaper 50 prererdbly comprises a liquid pervious topsheet 520; a liquid impervious backsheet 530 joined with the topsheet 520; an absorbent core 540 positioned between the topsheet 520 and the backsheet 530 the a~isorL,ent core 540 having a ~,ar"~ent facing surface 642, a body facing surface 544, side edges 546, waist edges 548, and ears 549. The diaper 50,c,rer~r~1y further com,u,ises elasticized leg cuffs 550;
an elastic waist feature multiply designated as 560; and a fastening system generally multiply designated as 570.
The diaper 50is shown in Figure 5 to have an outer surface 52, an inner surface 54 opposed to the outer surface 52, a first waist region 56, a second waist region 58 and a pe,iphery 51 which is defined by the outer edges of the diaper 50 in which the longitudinal edges are designated 55 and the end edges are desiy"ated 57. (While the skilled artisan will recognize that a diaper is usually described in terms of having a pair of waist 20 regions and a crotch region between the waist regions in this application for simplicity of terminology the diaper 50is described as having only waist regions including a po, Lion of the diaper which would typically be desiy"dled as part of the crotch region). The inner surface 54 of the diaper 50 co"".rises that polLioll of the diaper 50 which is positioned ~-5 cent to the wearer's body during use (i.e. the inner surface 54 generally is formed by at least a po,lion of the topsheet 520 and other colll~,ollellls that may be joinedto the topsheet 520). The outer surface 52 cor"prises that portion of the diaper 50 which is posiliGned away from the wearers body (i.e. the outer surface 52 y~nerallyis formed by at least a portion of the backsheet 530 and 30 other cor"po"e,)ls that may be joined to the backsheet 530). (As used herein the po, liGn of the diaper 50 or component thereof which faces the wearer is also refer,ecl to as the body facing surface. Similarly the portion facing away from the wearer is also refer,ed to herein as the garment facing surface.) The first waist region 56 and the second waist region 58 extend respectively from the end edges 57 of the periphery 51 to the lateral centerline 53 of the diaper 50. Figure 5 also shows the longitudinal centerline 59.

CA 0220~917 1997-0~-22 WO 96/17S73 P~ 5/15789 Figure 5 shows a prefer,ed embodiment of the diaper 50 in which the topsheet ~20 and the backsheet 530 have length and width dimensions generally larger than those of the absorbent core 540. The elasticized leg cuffs 550 and the backsheet 530 extend beyond the edges of the absorbent 5 core 540 to thereby form the periphery 51 of the diaper 50.
Diapers of the prese~t invention can have a number of well known configurations with the absorbent cores thereof being adapted to the present invention. Exemplary configurations are described generaily in U.S. Patent B1 3 860003 issued to Buell on April 18 1989; U.S. Patent 10 5 151 092 issued to Buell et al. on Se,ut~",ber 29 1992; and U.S. Patent 5 221 274 issued to Buell et al. on June 22 1993. Each of these palenl~ is incor~ordled herein by reference. Another diaper configuration to which the present invention can be readily adapted is described in co-pending U~S.
Patent Application Serial No. 08/203 456; filed on February 28 1994 in the 15 name of Roe et al. and incorporated herein by rere,t:"ce. The absorbent cores of diapers described in these pa~ents can be adapted in light of the teachings herein to include the absorbent composite of the present invention as an absorbent gelling material described therein.
A topsheet 520 which is particularly suitable for use in the diaper 50 20 is carded and the~ ally bonded by means well known to those skilled in the fabrics art. A s~lisractol y topsheet for co" ,~, ises staple length polypropylene fibers having a denier of about 2.2 As used herein the term "staple length fibers" refers to those fibers having a length of at least about 15.9 mm (0.625 inches). rreferably the topsheet has a basis weight from 25 about 14 to about 2~ grams per square meter. A suitable topsheet is manufactured by Veratec Inc. a Division of International Paper Company of Walpole Mass. under the designation P-8.
The topsheet 520 of diaper 50 is pr~ferably made of a hydrophobic material to isolate the wearer's skin from liquids which have p~ssed through 30 the topsheet and are contained in the absorbent core (i.e. to prevent rewet) If the topsheet is made of a hydrophobic material at least the upper surface of the topsl,eet is treated to be hydrophilic so that liquids will transfer through the topsheet more rapidly. This diminishes the likelihood that body PY.url~tes will flow off the topsheet rather than being drawn through the 35 topsl,eet and being ~Lsorbed by the absorbent core. The topsheet can be ,~:"~Jered hydrophilic by treating it with a surfactant. Suitable methods for CA 0220~917 1997-0~-22 WO 96/17573 PCT/US9S/lS789 treating the topsheet with a SUI r~an t include spraying the topsheet material with the surfactant and immersing the material into the surfactant.
A more detailed discussion of such a treatment and hydrophilicity is contained in U.S. Patents 4 988 344 entitled "Absorbent Articles with Multiple Layer Absorl,enl Layers" issued to Reising et al on ~anuary 29 1991 and U.S. Patent 4 988 345 entitled "Absorbent Articles with Rapid Acquiring Absorbent Cores" issued to Reising on January 29 1991 each of which is i~,cor,~oraled by rerer~"ce herein.
In a pref~rred embodi",e"l of a diaper as desc,iLed herein the backsheet 530 has a modified hourglass shape exte, Iding beyond the absorbent core a minimum distance of about 1.3 cm to about 6.4 cm (about 0.5 to about 2.5 inch) around the entire diaper peri,l~l)e,y.
The absGrLent core 540 may take on any size or shape that is co~"pdlible with the diaper 50. One pre~ned embodiment of the diaper 50 has an asy"""6l,ic modified T-shaped absorbent core 540 having ears in the first waist region but a generally rectany.llar shape in the secGnd waist region. Exemplary absorbent structures for use as the absorbent core of the present invention that have achieved wide acceptance and commercial sl ~ccess are described in the above ref~r~"ced and incor~oraled U. S.
Patent 4 610 678 and in U.S. Patent 4 673 402 entitled "Absorbent Articles With Dual-Layered Cores" issued to Weisman et al. on June 16 1987; U.S.
Patent 4 888 231 entitled "Absorbe"l Core Having A Dusting Layer" issued to AllgsLadl on December 19 1989; and the above ref~renced U.S. Patent 4 834 735. The absorbe"t core may further co""Jrise the dual core system containing an acquisition/disL, ibution core of cl ,e",ically slirrened fibers positioned over an absorbent storage core as detailed in U.S. Patent 5 234 423 entitled "Abso, b6~ It Article With Elastic Waist Feature and El ~l Idl ,ced Abso- b6l ,cy" issued to Alemany et al. on August 10 1993; and in U.S. Patent 5147 345 entitled "High Efficiency AbsorL,ent Articles For Incor,linence Managel . ,ent" issued to Young LaVon and Taylor on S~pl6,l,ber 15 1992. All of these patents are incor~oraled herein by ~ rerere"ce. The absorbent cores described in these pdle, ll~ can be adapted to include as an absorbent gelling material the absorbent composites of the ,c,resel ,t invention. Pl e~er~bly, the absorbent composite will be includedin a component of the aL,sorbenl core which functions ,clillla,ily to retain or store fluids as opposed to acquiring andlor distributing fluids (typically CA 0220~917 1997-0~-22 WO 96/17S73 PCT/US95/lS789 referred to as the storage layer or storage core). More preferably the absorbent core comprises hydrophilic fibers and the absorbent composite as described above in general rerere,lce to absorbent articles.
In a preferred embodi" ,enl the diaper 50 further comprises 5 elasticized leg cuffs 550 for providing improved containment of liquids and other body exudates; an elastic waist feature 560 that provides improved fit and contain~ent; and a fastening system 570 which forms a side closure which maintains the first waist region 56 and the second waist region 58 in an overlapping configuration such that lateral tensions are maintained 10 around the circumference of the diaper to maintain the diaper on the wearer.
The diaper 50 may also comprise elasticized side panels (not shown) in the waist regions 56 and 58 to provide an elastically exle"sible feature that provides a more co" ~rul la~le and contouring fit and more effeG~ive application of the diaper 50.
The elasticized leg cuffs 550 can be constructed in a number of dirrare"l configurations including those described in the above referenced U.S. Patent No. B1 3 860 003; U.S. Patent No. 4 909,803, issued to Aziz et al. on Mar. 20 1990; U.S. Patent No. 4 695 278 issued to Lawson on Sep.
22 1987; and U.S. Patent No. 4 795 454 issued to Dragoo on Jan. 3 1989 20 each being incorporated herein by rert:rt:"ce.
The el~sli~;~ed waist feature ,u,-ererably comprises an elasticized waistband (not shown) that may be constructed in a number of dirrert:"t configurations including those described in U.S. Patent No. 4 515 595 issued to Kievit et al. on May 7 1985; U.S. Patent No. 5 026 364 issued to 25 Robertson on Jun. 25 1991; and the above rerele"ced U.S. Patent No.
5 151 092 issued to Buell et al. on Sep. 29 1992 each of these rererel,ces being inco" orated herein by re~erence.
The elasticized side panels may be constructed in a number of configurations. Examples of diapers with elasticized side panels positioned 30 in the ears (ear flaps) of the diaper are disclosed in U.S. Patent No.
4 857 067 issued to Wood et al. on Aug. 15 1989; U.S. Patent No.
4381 781 issued to Sciaraffa et al. on May 3 1983; U.S. Patent No.
4 938 753 issued to Van Gompel et al. on Jul. 3 1990; and U.S. Patent No.
5 151 092 issued to Buell et al. on Sep. 29 1992; each of which are 35 incorporated herein by referel)ce.

CA 0220~917 1997-0~-22 Wo 96/17S73 PCr/US9S/15789 Exemplary fastening systems 570 are disclosed in U.S. Patent No.
4,846,815, issued to Scripps on Jul. 11, 1989; U.S. Patent No. 4,894,060, issued to Nesleyard on Jan. 16, 1990; U.S. Patent No. 4,946,527, issued to Battrell on Aug. 7, 1990; U.S. Patent No. 3,848,594, issued to Buell on Nov.
19, 1974; U.S. Patent No. 4,662,875, issued to Hirotsu et al. on May 5, 1987; and U.S. Patent No. 5,151,092, issued to Buell et al. on Sep. 29, 1992; each of which is incor,uordled herein by rererence.
The diaper 50 is ,ureferably applied to a wearer by positioning one of the waist regions of the diaper, prererably the second waist region 58~ ~nder the wearer's back and drawing the remainder of the diaper between the wearer's legs so that the other waist region, pr~fer~bly the first waist region 56, is positioned across the front of the wearer. The fastening system is then applied to effect a side closure.
The co,,,,uosiles of the present invention are useful in the absorbent cores of pantiliners. Exemplary pantiliners for which the present invention may be adapted are ~i;sclosed in U.S. Patent No. 4,738,676 entitled "Pantiliner" issued to Osborn on April 19, 1988, which patent is inco, ~oraled herein by r~rere"ce.
The composites of the present invention are also useful in the absorbent core of l,dWng pants. The term "training pant", as used herein, refers to d iS,~05Z'~ ~le ydl 11 ~nla having fixed sides and leg openings.
Trainin~ pants are placed in position on the wearer by inserting the wearer's legs into the leg ope"i"gs and sliding the training pant into position about the wearer's lower torso. Trail ,iny pants to which the present invention are readily adaptecJ are disclosed in U.S. Patent No. 5~246~433 issued to Hasse, et al. on Septe",ber 21 ~ 1993 Another dispos~le absorbent article for which the composites of the prese"l invention are useful are i"conli"e"ce articles. The term "il,co"li"ence article" refers to pads, u,,derydllllents (pads held in place by a suspension system of same type, such as a belt, or the like), inserts for absorbent articles, capdciLy booslers for absorbent articles, briefs, bed pads, and the like regardless of whether they are worn by adults or other incontinent persons. Inconli,-e,-ce articles to which the present invention can be readily adapted are disclosed in U.S. Patent No. 4~253~461 issued to Strickland, et al. on March 3~ 1981; U S Patent Nos. 4~597~760 and 4~597~761 both issued to Buell on July 1, 1986; U S Patent No. 4~704~115 CA 0220~9l7 1997-0~-22 issued to Buell on November 3, 1987; U.S. Patent No. 4,909,802 issued to Ahr, et al. on March 20, 1990; U.S. Patent No. 4,964,860 issued to Gipson, et al. on October 23, 1990; and in U.S. Patent 5,304,161, "Absorbent Article Having Rapid Acquiring Multiple Layer Absorbent Core," issued to Ahr on April 19, 1994 . The absorbent cores described in these patents can be adapted to include, as an absorbent gelling material, the absorbent composites of the prese"t invention.

ExamPles Absorbent composites are prepared from Nalco 1180 (particles of absorbent gelling material available from Stockhausen GmbH of Krefeld, Germany (hereinafter referred to in the examples as AGM), several fiber materials, and a 10% aqueous solution of Kymene~9 557 as bonding agent to bond the AGM and fibers. The fibers are abbreviated as follows:
CSF chemically stiffened, cellulosic fibers formed from Foley fluff (southern kraft pulp, Buckeye Cellulose Co,. Memphis, TN, USA) having a moisture cGnle, ll of about 7%, which are crosslinked with citric acid to the extent of about 3.8 mole% citric acid on a dry fiber cellulose anhydroglucose basis accordi"g to U.S. Patent 5,137,537 20 PP POLYSTEEN polypropylene fibers, available from Steen & Co.
GmbH, of Schwa,~enbek, Germany, being 2 denier and 6 mm i length PE POLYSTEEN polyethylene fibers, available from Steen & Co.
GmbH, of Schw~l enbek, Germany, being 4 denier and 4.6 mm in length BiCo POLYSTEEN fibers having a polypropylene core, polyethylene outer layer, available from Steen & Co. GmbH, of Schwa,~enbek, Germany, being 2.5 denierand 4.6 mm in length The percenlage of fibers and AGM particles of the composites is 30 shown in Table 1. In Table 1, Examples 1-5 represent absorbent composites accordi, lg to the present invention.
The composites are prepared as follows using equipment as described and configured in r~r~rence to Figure 2. The fibers are taken from a bale of the fibers using a fiber opener available from the LaRoche CA 0220~917 1997-0~-22 WO 96/17S73 PCI~/US9~;/15789 Corl~,ually. The opened fibers are further opened by an Ospray Surge Bin and then co",pacted using a Wright Vertical Mat Former. The fibers at this point are 95% - 99% open and have a density of 0.1 g/cm3. The resultant individualized fibers are then transported to two Dan Web fiber lay down 5 apparatii.
The Kymene~) solution is applied to the fibers while in the Dan Web ~p~ar~lii using a conventional humidification chamber. The Kymene~) solution is applied in an amount of 10-15 weight %, based on the weight of the fibers. Fibers having the Kymene~) solution applied thereon are laid 10 down by the first Dan Web a,u,u~r~lii onto a vacuum conveyor. The Dan Web apparatus lays the fiber/Kymene~ solution mixture down at a basis weight of 1 8g/m2 - 25 g/m2.
AGM particles are then deposited onto the first fiber web using a Nordson AGM Disperser. The AGM particles are iaid down at a basis 15 weight of 0.054glcm2 - 0.070 g/cm2. The fiber web having AGM particles deposited thereon then p~sses by the second Dan Web apparalus where a layer of fibers having Kymene~) solution distributed thereon is deposited ~dj~cent the layer of AGM particles. The fiber/Kymene~) solution mixture is laid down at a basis weight of 1 8g/m2 - 25 g/m2.
The fiber webs having Kymene~ solution distributed thereon and AGM particles deposiled lherebetween then move through a set of calendar rolls which combine and compact the fiber webs to ensure intimate contact between the fibers, K~llle~ ) solution, and AGM particles. The resultant cc"~p~c~ed web is then l~anspo,led to a through-air drying oven, available from ASEA Brown Boveri. The web is exposed to a temperature of about 300~F for a period of 1-2 minutes to dry or cure the K~llle"e~13) solution.
The resultant web is l,c,,,spo,led to another fiber opener (LaRoche) which opens the web and sep~, dles the fibers which have the AGM
particles adhered thereto. The material is then l,d"spo,led through a material handling fan (No~ en~ Blower Inc., Winnipeg, Manitoba, Canada, Model LS WHL), which further separales the fibers having the AGM
particles adhered thereto, to thereby form the absGrbenl composites.
Absorbent composites accordil,g to the present invention are made as desc, ibed in Examples 1-5, except that 10%, by weight, aqueous CA 0220~917 1997-0~-22 WO 96/17573 PCT/US9~/lS789 solutions of propylene glycol, glycerol, or ACCOSTRENGTH 711 are used as the bonding agent.

Table I
Example No. wt.%AGM wt.% CSF wt.% PP ratio CSF/PP

The following tests are pe~ru""ed at room temperature, unless otherwise indicated.
AbsorPtion CaPacitv and Fluid Retention of CGr"~osiles The Absorption Capacity and Fluid Retention of the absorbent 10 composites is deter",ined as follows. 0.3 grams of the composite is enclosed in a dry, pre-weighed 6 cm X 6 cm tea bag formed of a nonwoven.
The tea bag is immersed in an excess of sheep's blood for 10 minutes and then removed and allowed to drain. After a drai"i,lg time of 10 seconds, the tea bag is weighed and the weight is compared to the initial tea bag weight 1~ to determine the weight of fluid absorbed by the composite, the Absorption Capacity. The weight is not adjusted for the amount of fluid absorbed by the tea bag itself. The tea bag is then centrifuged at 1400 rpm for 10 minutes. The tea bag is weighed again and the weight is compared to the initial tea bag weight to determine the amount of fluid that is retained by the 20 composite (Fluid Retention). The Absor~ution Capacity (AC) and Fluid Retention (FR), in grams sheep's blood/gram composite, are calculated as follows:
AC = (tea bag weight after 10 minutes - empty tea bag weight) . (weight dry composite included in tea bag) WO 96/17S73 PCI'IUS9S/15789 FR = (tea bag weight after centrifugation - empty tea bag weight) .
(weight dry composite included in tea bag) Absor~liorl caPacitv Under Pressure of Composites The Absorption Capacity Under Pressure of the absorbent 5 composites is deter" ~ined as follows. A pre-weighed sample of the composite (approximately 0.9 grams) is placed in a small container with a sieve at the bottom (weight of the sample is Wj). A suitable weight is placed on top of the sample to create a pressure of 0.2~ psi on the sample.
The container and its co, llel lls are weighed and placed on a filter plate in a10 Petri-dish which is filled with sheep's blood at room temperature (20-25~C), such that the sieve comes slightly into COIlLdCl with the blood. After one hour the sample is removed from the container and re-weighed (weight of the sample after 1 hour is Wa). The Absorption Capacity Under Pressure (ACUP), in grams sheep's blood/gram coin~,osile, is ca~c~ ted as follows:

ACUP= Wa-W
Wj CA 0220~917 1997-0~-22 WO 96/17S73 PCT/US95/lS789 Acquisition Time and Acquisition Rate of ComPosites The Acquisition Time (AT) of the composite is determined as follows.
5.00 + 0.15 ml of sheep's blood is delivered to the composite through a fixed area opening in 3.4 seconds under a 0.25 psi load. The time to 5 acquire the sheep's blood, i.e., the Acquisition Time, is ~cor:led using an electronic strike-through plate and timer. A built-in sensory probe dele~s the presence of the sheep's blood which triggers the start of the timer.
When completely drained, the timer stops. The Acquisition Rate (AR) is calculated as follows:
AR = ml sheep's blood delivered to the composite Acquisition Time The Fluid Rete"lion, Absorption Capacity Under Pressure, Acquisition Time, and Acquisition Rate of the Corl "~osiles 1 -5 and 15 Comparative Example Composite 1 are shown in Table ll. Similar results are obtained where PE or Bico is substituted for PP in the Col"posiles 1-5 or the Comparative Example Composite 1.

Table ll ExampleFluid Absor,uliG" Acquisition Acquisition No. Retention, Capacity Time, Rate, g/g Under secGnds ml/second Pressure, 23.3 33.2 19.0 0.26 2 23.1 36 23.7 0.21 3 28.1 42.2 18.0 0.28 4 20.9 34.4 22.0 0.23 21.9 32.2 25.0 0.20 CE 1 20.9 31.6 59.0 0.085 CA 0220~917 1997-0~-22 wo 96rl7s73 PCTIUS9~/15789 The above data shows that absorbent composites prepared using the chemically stiffened cellulosic fibers provide Acquisition Times and Acquisition Rates that are significantly lower than those provided by absorbent composites that do not include any of the chemically slirrened 5 cellulosic fibers. In addition the tabulated values show that absorbent co",,,~osiles 1-3 corlldirlillg chemically slirr~:"ed cellulosic fibers provide Fluid Retentions that are significantly higher than absGr~e"t co"~posiles that do not co"lai" any chemically slirr~"ed cellulosic fibers. This is surprising since the absorbent composites 1-3 contained less AGM ~dL~:I ial 10 than the composites 4-5 and CE1 and Fluid Retention is expected to increase with an inc, ease in AGM cor,cel ,l, dlior,.
Laminates are formed from the composites and tested for Absorption Capacity Under Pressure Fluid Rete~lio~ and Acquisition Time. l~he laminates are formed by air-laying about 7 grams of a single composite 1~ material onto a prc ~J/ci ~l,ed 5 cm X 20 cm layer of diaper standard tissue (basis weight 0.063 - 0.070 oz/sq. foot (19.4 - 21.3 g/m2)) and covering the composite with another pre-weighed 5 cm X 20 cm layer of diaper standard tissue (the actual amount of composite in grams Wj is measured). The composite is sl~l~st~llially uniformly air laid on the lower tissue layer and 20 the tissue layer edges are registered.
Absorption caPacitv Under Pressure of Lami"dles Absorption ~ar~city Under Pressure of the lar"i"dle is determined as follows. A 5 cm X 7 cm sample of the laminate is placed in the flat unfolded configuration in a conl~i"er having a sieve positioned at the 25 bottom. A suitable weight is placed on top of the laminate to create a pressure of 0.25 psi over the entire area of the la",inale. The COI ,tainer and its co, ll~nts are weighed and placed on a filter plate in a Petri-dish which isfilled with sheep's blood at room temperature (20-25~C) such that the sieve comes slightly into co"~acl with the blood. After one hour the laminate is 30 removed from the container. The amount of blood which is absorbed by the laminate is measured by weighing back the conla;ner.
The Absorption Capacity Under Pressure (ACUP) of the la",il,a~e in grams sheep's blood per gram of composite is then c~lçl ll~ted as follows:

3~; ACUP = ( Wl - Wt ) Wac CA 0220~917 1997-0~-22 WO 96/17S73 PCI~/US9~/15789 ~4 where Wl is the amount of blood absorbed by laminate Wt is the amount of blood absorbed by the tissue and Wac is the dry weight of the absorbent composite in the laminate namely 7 grams.
The amount of the blood absorbed by the tissue is calculated as follows:
(area of tissue in laminate) X (basis weight of the tissue) X (the absorption ca~aoily under pressure of the tissue for sheep s blood which is 3 grams sheep's blood /gram tissue) X 2 10 If necess~ry the absorption capacity under pressure of the tissue is determined in the same manner of the lamir,ale using calculations readily unde,atood by the skilled artisan in light of the ~Ic~ tions described in refert:"ce to the absorbent com,uosiles.
The Acquisition Time Absorption Capacity and Fluid Retention of 15 the laminates are determined in the manner described in rere~e.,ce to the al)sor~e"l con"~osiles except that a sample of the lar"indle is substituted for the absorL,e"t composite. The laminate sample to be tested weighs the same as noted for the absorbent composite.
The Abs~l,ulio" Capacity Under Pressure Acquisition Time and 20 Fluid Retention of the Laminates containing CGm~ osiles 1-5 and Cor,,,ud,dli~e Example Col"~osile 1 are shown in Table lll.
Table lll Example No. Absorl.lion Acquisition Fluid Retention Capacity Under Time seco"ds 9/9 Pressure g/g 33.2 19 23.3 2 35.8 19.5 23.4 3 42.2 18 28.1 4 34.4 22 21.1 32.2 25 21.9 CE1 35.1 58 21.6 ~ .
CA 0220~917 1997-0~-22 WO 96/17S73 1 ~ 5/lS789 ~5 The t~h~ ted values show that abso,be"t composites collldil~ y chemically stiffened cellulosic fibers provide laminates having Acquisition Times that are significantly lower than the laminates containing absorbent composites that do not cGnLain the chemically stiffened cellulosic fibers.
5 The relatively high Acquisition Time for the laminate c~"lai~ ling the Comparative Example Composite 1 indic~tes that gel blocking is occurring to a significantly greater extent than in the other la",i,)ales. In addition thetabulated values show that absorbent composites 1-3 CGI ,lait,ing chemically stiffened cellulosic fibers provide lar"ir,ales having Fluid 10 Retentions that are significantly higher than the lalllillates co"ldining absorber,l composites that do not contain the chemically slirre,led cellulosic fibers. This is surprising since the absorbent composites 1-3 conl~i"ed less AGM material than the co"~posiles 4-5 and CE1 and Fluid Retention is~
expected to increase with an i, Ic~ ease in AGM conce"l, dlion.

While particular embod;l),er,ls of the pres~nl invention have been illustrated and desc, ibed it would be obvious to those skilled in the art that various other changes and IllGdiricaliOlls can be made without departing from the spirit and scope of the invention. It is ll ,ererore intended to cover 20 in the appended claims all such changes and modifications that are within the scope of this invention.

Claims (9)

What is Claimed is:

1. An absorbent composite comprising particles of polymeric, absorbent gelling material in substantially individual form and chemically stiffened, cellulosic fibers having ends, characterized by said fibers being wrapped around and adhered to said particles such that said fiber ends protrude from said particles, wherein the fibers that are wrapped around a given particle of polymeric, absorbent gelling material are substantially separated from the fibers that are wrapped around other particles of polymeric, absorbent gelling material of the composite, said fibers preferably being adhered to said particles by a bonding agent.

2. The absorbent composite of Claim 1, additionally comprising synthetic polymeric fibers having ends, said synthetic polymeric fibers being adhered to said particles such that said ends of said synthetic polymeric fibers protrude from said particles.

3. The absorbent composite of either Claim 1 or Claim 2 wherein said fibers of said composite are chemically stiffened by the reaction of a crosslinking agent with the fibers to form intrafiber crosslink bonds.

4. The absorbent composite of any one of the preceding claims further comprising synthetic polymeric fibers having ends, said synthetic polymeric fibers being adhered to said particles such that said ends of said synthetic polymeric fibers protrude from said particles, said composite preferably comprising from about 90% to about 30%, by weight of the composite, of said particles of absorbent gelling material, and from about 10% to about 70%, by weight of the composite, of said chemically stiffened, cellulosic fibers.

5. The absorbent composite of any one of the preceding claims wherein said bonding agent is selected from the group consisting of hydrophilic organic solvents; volatile hydrophobic organic compounds, water; cationic polyacrylamides; cationic amino-epichlorohydrin adducts; and mixtures thereof, and preferably is a mixture of water and a compound selected from the group consisting of cationic polyacrylamides, cationic amino-epichlorohydrin adducts, and mixtures thereof.

6. An absorbent article comprising a liquid pervious topsheet, a liquid impervious backsheet, and an absorbent core disposed therebetween, said absorbent core comprising the absorbent composite of any one of the preceding claims.

7. A method of making an absorbent composite comprising particles of polymeric, absorbent gelling material in substantially individual form and chemically stiffened, cellulosic fibers having ends, wherein said fibers are wrapped around and adhered to said particles such that said fiber ends protrude from said particles and wherein the fibers that are wrapped around a given particle of polymeric, absorbent gelling material are substantially separated from the fibers that are wrapped around other particles of polymeric, absorbent gelling material of the composite, the method characterized by the steps of:
(a) providing particles of polymeric, absorbent gelling material and chemically stiffened, cellulosic fibers having ends;
(b) applying a bonding agent in liquid form onto said fibers to form treated fibers;
(c) physically associating said particles of polymeric, absorbent gelling material and said treated fibers while said bonding agent is in liquid form, said particles being in substantially individual form, such that said fibers wrap around said particles and said fiber ends protrude from said particles; and (d) adhering said particles and said fibers.

8. The method of Claim 7 wherein said fibers are individualized prior to said step (b) of applying said bonding agent, or said fibers are provided in the form of aweb and said bonding agent is applied to said web.

9. The method of Claim 7 wherein said step (c) of physically associating comprises applying an external force selected from the group consisting of pressure, vacuum, electrostatic forces, impact, impingement, or combinations thereof.