US 2902395 A
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SCP- l, 1959 H. w. HlRscHY ETAL 2,902,395
ABSORBENT WIPING SHEET Filed Sept. 30, 1954 3 Sheets-Sheet l Z4 Z6 Z7 mvENToRs, HARL-AN w. HmscHY, CARL H, Rowe, KENNETH J. HARwoon Sept. l, 1959 H. w. HlRscHY ETAL 2,902,395
' ABsoRBENT wIPING SHEET Filed Sept. 30, 1954 5 Sheets-Sheet 2 34 iNVENTORS HARLAN W. HIRSCHY, CARL, H. RWE,
KENNETH J. HARWOOD Sept. 1, 1959 H. w. l-nRscHY ETAL 2,902,395
ABSORBENT wIPING SHEET filed sept. so, 1954 3 sheets-sheet s INVENTORS` HARLAN w. HlRscHY, CARL H. Rows.
KENNETH J. HARwooo nit ABSORBENT WIPING SHEET Harlan W. Hirschy, Neenah, Carl H. Rowe, Appleton, and Kenneth J. Harwood, Neenah, Wis., assignors, by mesne assignments, to Kimberly-Clark Corporation, a corporation of Delaware Application September 30, 1954, Serial No. 459,275
4 Claims. (Cl. 154-46) other forces to which the products are subjected in their normal uses; to provide such sheet material which may be folded and lumpled in both dry and wet state, like a conventional textile dusting or wiping cloth; and to provide products such as toweling, wiping `material and similar sheet material which has a good capacity for absorbing water, oil, or other liquids without `disintegrating, and which is usable, according to its construction, for afwide variety of purposes. In general, it is the object of this invention to provide improved products of the character indicated.
Other objects and advantages of the invention will be understood by reference to the following specication and accompanying drawings wherein there are illustrated certain selected products embodying selected forms of the invention together with schematic representations of various steps which may be employed for producing the products or elements thereof.
In the drawings:
Fig. l is a plan on an enlarged scale of a netlike web or fabric constructed of threads and which typies one element of several forms of products according to the invention, certain proportions being exaggerated to facilitate illustration;
Fig. 2 is a fragmentary perspective of a component of the web represented in Fig. l;
Fig. 3 is a cross-section on the line 3--3 of Fig. 1;
Fig. 4 is an enlargement of a portion of the sectional illustration shown in Fig. 3;
Figs. 5, 5a and 6 are fragmentary plan views of selected forms of material according to the invention; and
Figs. 7 and 8 are respectively, schematic representations of various method steps for producing products, or elements of products embracing the present invention.
The fabric represented in Figure 1 is a component of many products of the present invention. It is a nonwoven fabric which comprises a set of threads 1 which extend lengthwise of the fabric, and a second set of threads 2 which extend crosswise of the length of the fabric. The threads in each of said sets are preferably but not necessarily disposed in parallel, substantially spaced relation to each other, the set of threads 2 being disposed wholly or entirely on one side of the other set of threads l, the said thread sets being disposed in face-to-face relation to each other and adhesively bonded together where the threads of one set cross the threads of the other set.
States Patent Cf Paffented Sept. 1, 1959 ICC Various forms` of apparatus are known for producing fabric of this non-,woven cross-laid thread construction. One suchappar'atus is schematically represented in Figure 7 where a series of parallel threads 1 are shown as being guided across an adhesive applying roller 3 which rotates in a pan 4 of adhesive, the threads being suitably guided from said adhesive applying roller 3 into circum# ferentially spaced relationship about an elongated eylindrical mandrel 5. A guide member 6 serves, in part, the purpose of guiding the threads into said circumferentially spaced relationship about the mandrel. Depending upon the type of adhesive used, provision may be made to dry or partially dry the adhesive on the threads to prevent wet adhesive from gumming up the guide 6 and mandrel 5, and suitable provision such as heating or inoistening means may be provided for reactivating the adhesive at the required time to make such adhesive useful for bonding the threads together and other components to the threads 1. The threads are advanced lengthwise along said mandrel, and a rotated ring 7 which carries one or more spools 8 of thread, wraps thread around said mandrel 5 and the threads l thereon to produce a tube 9 of fabric consisting of a set of lengthwise threads and a set of crosswise threads extending around the threads 1. The tube is slitted `lengthwise by a suitable slitter indicated at 1l] and the fabric tube then opened up to form a hat single ply fabric web 11. The thread applied from the spool 8 thus becomes the cross threads 2 of the fabric shown in Figure 1 and said cross threads are bonded to the threads 1 by means of the adhesive which was applied by the adhesive applicator roll 3. Any suitable means (not shown), such as a doctor blade for example, may be associated with the roll 3 to control the depth of adhesive applied by the roll to the threads. i
The cross threads 2 are effectively bonded to the lengthwise threads 1 but adhesive-stiening of the crosslaid thread fabric is nevertheless` avoided to a significant degree. Adhesive stiifening of the fabric is avoided rst by constructing the fabric with `one set of threads, the cross-threads 2 in this instance, free of adhesive intermediate the thread intersections so that said cross-threads retain very nearly their full normal flexibility and softness. Adhesive stiffening of the fabric is also to some extent avoided when, as in this instance, the adhesive-free threads are capable of and do absorb adhesive from the adhesive coated threads at the intersections so that at each intersection there is, is effect, a reduced amount of adhesive in or on the adhesively coated thread; this results in a short length of thread at the intersection, which is somewhat more flexible than4 those portions of the thread which carry the full application of adhesive. It may be observed that the absorption of adhesive in this manner at the thread crossings does not materially affect the flexibility of the cross threads which, except for such absorbed adhesive, are free of adhesive.
Adhesive stiffening of the fabric may further be avoided by causing the formation of adhesive voids or adhesivefree thread portions 13, more or less as disclosed in Harwood et al. Patent 2,564,689. This may be accomplished by so forming or operating the adhesive applying roller 3 that the adhesive will be discontinuously applied to the longitudinal threads 1. For example, the roller 3 may be provided with one or more recesses which will not carry adhesive to the threads, or said roll may be a smooth surface roll and operated at a surface speed which is somewhat less than the speed of travel of the threads 1 so that there is a tendency for the adhesive to be stretched out along the threads 1 as they leave the roller 3. This relationship may be such that the adhesive coatings will actually be broken at various points, thereby to 3; provide at leasty short adhesive free lengths along the longitudinal threads 1 such as indicated at 13 in Fig. 1.
IfA preferred, the adhesive applying roll 3 may be providedv with a heliealor othergrooverz which willserve to interrupt the adhesive application inV such a manner that the adhesive voids 13 fon each-thread will be in offset or staggered relation to-those onthe adjacent threads as shown in Figure l. With that arrangement, it' is made reasonably certainthat no cross threads 2'will engage adhesive'voidson adjacent adhesive-bearing threads 1, whereby adequate bonding of the'fcross threads 1 to the longitudinal threads 1` isassured.l
In some forms of apparatus for producing cross-laid thread fabric, therelatively cross-laid threads" are disposedin diagonal relationship instead of. in lengthwise andcrosswise relationship to the length of the fabric formed, the resultingweb being then generally characterized as a diamond network web. Such-webs may, in someproducts, be substituted for a web having lengthwise-and crosswise extending threadsV as represented in Figure l.
Cross-laid'fabrics have heretofore been produced from relatively stiff, heavy weight fibers such as glass, hemp, etc., to form reinforcing Webs, especially in certain types of building papers and heavy wrapping papers. The hard and stiff nettingsV so formed are not-suited to the products herein contemplated which, in general, should be soft and flexible and capableof being folded and rumpled on themselves like soft textile materials.
To attain softness and certain `other characteristics in the cross-laid thread fabric, it is intended that the threads 1 and'2 be in the form of low twist multiple filament threads as distinguished from conventional spun fiber threads. of continuous length filaments of rayon, nylon, and other materials which may be formedV into thedesired low denier, very flexible filaments.' In one example, the lengthwise threads 1 were made of 30 rayon filaments tocprovide threads of 75 vdenier and thecrosswise'threads 2 were made of 40 such filaments to form threads of 100 denier. All of the threads'were of low twist construction, the lengthwise threads being of about 21/2 twist per inch and the crosswise threads of about'4 twist per'inch. In general, the multi-filament threads should have a` denier within the range of about 30 to 150 and embody from 2 to 150 individual, continuous filaments having a denier within the range of about l to l', the'threads having'a twist less than' 6 per inch.v Y
Threads ofthe indicated low twist, multiple filament construction are quite flexible and soft and as a result of spooling and `other handling, suchthreads tend to assume a somewhat flattened or oval form as indicated at 14 in Figure 2. When threads of this character are cross-laid to form the fabric represented in Figure 1, the filaments tend to fan out at'the thread crossings to form flattened, increased-width` crossings as represented in Figure l. This flattening effect is highly ldesirable and may be increased by the application of light pressure to press the cross threads 2'into intimate contact with the lengthwise threads 1. This flattening effect may also be increased by rubbing, brushing or4 similarly working the threads either in the'localized areas of the thread intersections or along their entire lengths so 'as to flatten the entire lengths of-the threads. Such flatteningover theentire lengths is, ingeneral, quite desirable in that itreduces the thickness of the cross-laid thread web and thereby facilitates embodiment of-the same ina laminated sheeting with-minimum visible evidence of the'presence of the cross-laid thread fabric inthe sheeting.
One ofthe thready crossings after the application of light pressure, is shown1on an enlarged scale in Figure 4 where the lengthwise. threadl is shown attened to onlyslightly more than one-half its vnormal thickness, the cross thread 2 being similarly flattened andin effect, recessed to receive the flattened lengthwise thread 1'.
These m-ultple filament threads may be formed Both threadsare, of course, pressed into each other so that in side view, the lengthwise thread 1 would appear substantially as does the cross thread 2 in Figure 4. This flattening of the cross-laid threads at their intersections serves to largely eliminate from the fabric excessive thicknesses such as are usually present in woven fabrics at the threadintersections or knuckles, and it serves to somewhat increase the interengaging areas of the intersecting thread portions so that adhesive bonding of such portions to each-other is substantially improved or' strengthened. It also lappears that the reduction'in thickness of the threads at their intersections imparts increasedA flexibilityl thereto in areas of said reduced thickness.
The low twist, adhesively bondedfthread construction employed in making the cross-laid thread fabric of Figure l results in a very soft and limp but dimensionally stable fabric.
The-adhesiveemployed may be of any type suitable to the-purpose for which the fabric is prepared; One
type of adhesive whichA has general utility for the production of fabric according to Figure l and which is especially suitable lfor application by means of an'applying roller, isv polyvinyl acetatel solutionV containingr a plasticizer.' One exampleof such adhesive may contain 30'percent polyvinyl acetate, 67 percent solvent (commercial Solox, an alcohol base preparation), and` 3 percent ofv dibutyl phthalate plasticizer.`
The adhesive'is, for manypurposes, preferably one which remains ilexibleand which does not deeply penetrate the threads but rather tends to remain surfaced thereon. Adhesives of the emulsion, plastisol, or organisol types may be used as may also'hotl melt type adhesives such asl polyethylene. Adhesives which are thermoplastic in character are usually preferred and may be reactivated ork softened by the application of heat or by the use of'suitablesolvents to permit pressure embedment of one set of threads into the adhesive carried by the other set and to facilitate lamination of other materials to the cross-laid thread web through the agency of adhesive carried by the latter. The adhesive ernployed' should, of course, be selected in accordance with the use to which the fabric is to be put. In some instances water-proof adhesives are indicated and in other instances, oil-proof adhesive may be required. In still other instances water-proofness or oil-'proofness may be of no importance and considerations of flexibility and strength ofbond regardedas the main requirements.
For many purposes, a cross-laid thread fabric web such as represented in Figure 1 may have applied to it an applique l5 of fibers such as cotton or synthetic fibers. This applique may be in the form of a carded or otherwise integrated web but for many purposes this applique may consist of a very thin, flimsy, light weight, and highly pervious layer of fibers. For some purposes a fiber layer or applique having a weight of about 11/2 grams per square yard of fabric is desirable. A low weight fiber applique of this character is very pervious to liquid and does .not significantly reduce the permeability of the thread fabric. Nevertheless it provides a sheath or shield which imparts a smooth and soft feel to the thread web. Such an applique of bers may be applied to both sides ofthe thread web but it is usually not necessary, especially when the web is of an open mesh construction such as 5 x 5 or even 18 x 14, since some of the fibers applied to one side Will usually project through the web to suchan extent that a smoothening effect is readily` noticeable en both sides of the web.
The fibers of the non-woven applique 15 may be adhesively bonded to the thread web as hereinafter explained and these fibers are preferably of such a length thatV many of the-fibers will bridge adjacent pairs of threads and bridge across the angles formed by intersecting threads to thereby hold and brace the threads in their desired assembled relationship. This fiber connection of both parallel and cross threads may occur even in the absence of adhesive connection of fibers to the threads since the fibers have an inherent tendency to cling to the threads, but the said stabilizing effect is probably best attained when the fibers are adhesively attached to the threads.
The liber applique may be applied by various types of mechanism one of which is typified in Figure 8 where a bat 16 of the selected fiber material is fed endwise against a picker or similar disintegrating Wheel 17 which disintegrates the bat 16 and discharges a stream 1S of fibers against a web 19 of cross-laid thread fabric to thereby form the applique 15 on the side of the fabric formed by the cross threads 2. The cross-laid fabric 19 may be guided through the zone of operation of the picker wheel 17 directly from the apparatus by which the cross-laid fabric is produced so that the adhesive on the lengthwise threads 1 remains at least slightly active on its surface in the zone in which the fibers are deposited on the fabric.
The adhesive bonding of the fibers to the threads, and of threads to threads, may be substantially improved by conducting the fiber surfaced cross-laid web through a calender roll stack such as represented at 20. The cross threads 2 are thereby pressed into the adhesive carried by the lengthwise threads 1, and the threads are pressed into each other to attain the thread flattening effect represented in Figure 4 and the resulting increased area of adhesive bonding of the threads to each other. The fiber applique is also pressed into the thread fabric and some of the fibers caused to be more completely embedded in the adhesive carried by the threads 1 to more securely bond the fiber applique to the cross-laid thread web. As represented in Figure 3, the fiber applique 15 after being pressed against the crosslaid thread web appears to be more or less compacted in the areas of the threads as represented at 21 while retaining comparative flufliness in the areas of the interstices of the fabric as represented at 22. where some of the fibers are also caused to penetrate through the thread fabric so as to be in evidence on the face of the fabric opposite to that on which the fibers were initially deposited. The areas of said interstices constitute a large majority of the area of the fabric so that the fluffness of the fiber applique in said areas providespin effect, an over-all iiufliness or soft cushion effect.
The calendering rolls may be heated to reactivate thermo-plastic adhesive when used, and it is usually preferable that the cooperating calender rolls between which the material is passed comprise a steel roll and a cotton roll in Order to avoid cutting of the cross-laid threads at their intersections. When one of the rolls, for example the roll 23, is of cotton construction, it is preferable that the lengthwise threads 1 of the fabric 19 be on the side of the fabric which engages said cotton roll 23 (which is usually somewhat cooler than the cooperating steel roll) so that said threads will be effective to strip the cross threads 2 and the fiber applique 15 from the roll 23 to which they may otherwise tend to adhere. The fiber applique and the `adhesive-free threads 2 will prevent adhesive attachment of the adhesive-bearing longitudinal threads to the other roll.
The thickness of the fiber applique 15 may, of course, be varied to suit the intended end use of the material. This thickness is dependent upon such variable factors as the speed of travel of the cross-laid thread web 19 through the fiber applying Zone, the speed at which the bat 16 is fed to the picker 17 and the thickness or weight of the bat 16.
A form of cellulosic sheet material embodying the above described cross-laid thread material is represented in Fig. 5, this sheet material being in the nature of industrial wiping material to be used as a substitute for conventional textile cloth wipes. The material there shown comprises a Vplurality of plies of crepe tissue paper or wadding, in this instance, six plies indicated at 24. Theseplies are adhesively bonded to each other in a multiplicity uniformly over the entire area of the multi-ply web of. For industrial wipes purposes the waddingv wadding. plies may be formed of a high percentage of unbleached wood pulp formed into very thin, highly pervious and very tenuous, crepe tissue material with but little wet' strength but high absorbent capacity; this material rep-l resents a Very low cost cellulosic component of thel sheeting.
On the opposite faces of the multi-ply wadding web, there are very light, non-Woven layers 26 of fibers, and outside of these respective fiber layers there are nettings or webs 27 of cross-laid threads. Webs 27 of cross-laid threads and the layers 26 of fibers are supplied in the form of cross-laid thread webs with ber appliques there on as represented in Figure l, such combined. components being delivered as preformed webs into assembled relationship with the bonded plies of wadding. The` fiber layers 26 being very light, say within the range of l1/2 to 6 grams per square yard, are very pervious and permit the adhesive carried by the longitudinal threads of the cross-laid fabric component 27 to penetrate said fiber layers to come into engagement with the surfaces of the wadding filler thereby to effect adhesive bonding of said cross-laid thread fabrics and fiber layers to said wadding filler. This adhesive attachment of the cross-laid thread fabrics and the fiber layer to the wadding filler may be insured by the application off relatively light pressure, as for example by passing the assembled materials between suitably spaced and loaded calender or pressure rolls. If the adhesive employed on the thread web is of thermoplastic character, it may be reactivated by employing at least one heated calender roll at a temperature sufficient to suitably act on said adhesive.
A modification of the `arrangement shown in Figure 5 is represented in Figure 5A where the wadding plies 24 are bonded together by means of a series of lengthwise extending adhesive bearing threads 28. These threads are passed through a bath of adhesive or otherwise suitably coated with adhesive immediately preceding their delivery into position between the respectively adjacent wadding plies 24. The adhesive may be applied to such threads in an amount which will be sufficient to cause the adhesive to penetrate the adjacent and next adjacent plies of wadding so that all of the wadding plies will become adhesively bonded together. The adhesively coated threads 28 serve not only as an adhesive applying medium but also to impart tensile strength to the absorbent layer of tissue in the direction of said threads. The outer faces of the assemblage of wadding plies are covered with crosslaid, low twist thread fabric with fiber facings, as shown in Figure 5, such covering fabrics being adhesively bonded to the outer faces of the wadding assemblage in the manner above explained.
In some instances, bonding of the various elements of the described sheeting to each other may be aided by incorporating in either or both the cross and machine direction threads and in the fiber applique, thermoplastic fibers which may be reactivated incident to calendering or other treatment which will suitably reactivate the fibers and cause them to become adhesively attached to the adjacent components of the sheeting.
To attain extra strong interbonding of the wadding plies of the absorbent body, adhesive may be suitably applied to one or more of the inner wadding plies of the absorbent body, for example by spraying or printing, the adhesive being applied in such an amount that it will penetrate the desired Wadding plies to adhesively bond the same to each other and to plies on opposite sides of the ply or plies to which adhesive is so applied. The amount of adhesive so applied may, of course, be controlledto .limit the extentto which ,the adhesive willpenetratenother rplies, and thevapplication kof adhesive is preferably domein such a manner that it will occurin a multiplicity of ldiscrete areas over the lply rather than as a continuous ilm` over the entire area of thel ply, thereby to avoid stitfening of the product.
A further alternative is represented in Figure 6 where the absorbent filler comprises a central layer 31 of socalled fluff material, ie., cellulosic fibers deposited in a layer of the desired depth. Such a layer of fluff may be collected between plies SZ'and 33 respectively of crepe tissue paper wadding, these plies being of either single or multiple ply constructionA as desired. The, assemblage of iiuff and, crepe tissue paper retainers may be bonded together .by amultiplicity of embossed areas such las indicated at 34. A iiuff bodied filler of this character may be embracedv between protective surface coverings of fiberlined, cross-laid threads as described in connection with Figure 5.
The described products shown in Figures and 6 may be assembled in any suitable manner. One method of producing the product shown in Figure 5 is schematically illustrated in Figure 8. As there shown a web 19 of crosslaid fabricA is guided through the zone of operation of mechanism which deposits the desired layer of fibers on the cross-laid fabric which may then be calendered by means V.of a suitable calender stack 20 to produce the fiber faced cover web 27 for one side of the product.
A roll consisting of the required six or other number of tissue webs, or fluff and tissue paper, bonded together in the selected manner, for example as above described in connection with Figures 5 and 6, is suitably supported and the web 36 delivered therefrom into superposed relation to the cover web 27 produced as aforesaid. Another roll` 38 of cover material prepared in the same manner but wound into a supply roll, is suitably supported and the web 39 drawn therefrom and delivered into superposed relation to the wadding layer 36. The assemblage is then subjected to pressure between a pair of pressure rolls 4t) which may be heatedto reactivate thermoplastic adhesive carried bythe longitudinal threads of the cross-laid fabric in the cover webs to thereby elect adhesive bonding of said cover webs to the absorbent wadding layer inthe manner already explained. Other methods of assembling the components may, of course, be employed and the described method is merely intended to be representative of one arrangement. Y
One example of wadding` material made according to Fig. 5a, embodied six plies of unbleached creped tissue paper formed mainly of unbleached wood pulp, the individual plies having a basis weight of about 6.5 pounds per ream of 480 sheets, measuring 24 by 36". The adhesive carrying threads 28 were very fine multiple rayon iilamentthreads of low twist embodying 30 filaments having a twist of about 21/2 per inch, the resulting threads being of 75 denier. These threads were coated with polyvinyl acetate adhesive having the composition above mentioned. The weight of the adhesive carried by such threads per square yard of fabric was 2 to 3 grams. The cross-laid thread fabric was ofv a l0 X 5 mesh and consisted of low twist rayon filament threads disposed at substantially right angles to each other withV one set ofA threads extending lengthwise of the finished product and the other set extending crosswise thereof. The cross direction threads were of 100 denier comprising 40 filaments and the machine direction threads were of 75 denier comprising 30 rayon filaments.
The last described product has a thickness of about .03() to .04() inch and, despite its laminated construction, is very soft and flexible, quite limp, and capable of being rumpled and formed into a pad for wiping purposes. lts softness is such that it could be made to conform quite closely to irregular surfaces andto sharp corners and recesses. The material, although not made of waterproof or wet strength paper may nevertheless be wetted and.
8 rumpled intoa zpad like a textile wiping cloth and then stretchedrouftintofflat sheet form; ldried, and reused,
either, wet or Thelplyviiiylfacetate adhesive `ein-v ployedfor bonding theqcross-laid thre`ad"fabrcis` to the assemblage of wadding plies is substantially ymoistureproof Y andv resists Aseparation of the thread `webs fromthe assemblage lofrwaddiilg lplies so that said cross-laid thread` e webseconstitute permanent protective facings for the waddinaples Thesaid cross-laid thread webs not only impart substantial tensilelstrengthto the paper ply assemblage butv also provide surface protection which prevents to a' subl very destructive (if` soft'tissue paper, especially when wet. This wadding protecting function of the fiber faced cross-laid web may, of course, be increased by employing less open mesh net-like fabrics or heavier threads, and
heavier berappliques. However, said surface covering thread webs or vprotective grilles, when made as hereinabove described, especially when made of low twist multiple lamentfthreads, are of sufficiently limp and open mesh'form'ation Vthat'they do not greatly affect the hand of the composite material; hence, the`hand of the composite material is' predominantly determined or supplied by the body of superposed plies of"cellu1ose"wadding, which body is soft, flexible and compressible'so as to contribute to the product, many of the characteristics of textile toweling and wiping cloth.
The vber applique is a highly important element in the protection of the wadding in'that it tends to form a layer in the nature of a very pervious screen whichis smooth and substantially less abrasive than the wadding. This screen is so porous that it does not offer significant resistance to the absorption ofV liquids by the absorbent body and the smooth and non-abrasive character thereofI facilitates movement of-material over a surface inV a wiping operation. This smoothness is, however, not of such a continuous film like character as to interfere with the pick upA of dirt and other foreign matter from a surface, it being observed that the paucity of fibers in the ber appliquev which provides high permeability as already mentioned also lindicates such spacing ofthe fibers that pocket-like spaces are provided into which dirt and other foreign matter may be crowded in a wipingoperation.
For certain wiping purposes it is preferred'that; the threads which are employed'in the protective surface. coversbe of such very light weight that they will break in the event that they` are hooked on a burr or other projection rather than be pulledout of the fabricincident to the movement of the material across such a projection. The strength ofthe threads for this purpose should, of course, be determined at least partially in view of. the strength of the adhesive bond which is effectedbetween the threads and the absorbent body so that the adhesive bond willretain the threads and cause the same to Abe broken under the circumstances above referredr to.
Instead of forming the fiber web 15 on the thread fabric inthe manner shown in Figure 8,V the fibers may be preformed'intoa web, as by carding or other methods and the preformed fiber web assembled with the other components in any suitable manner.
Tests indicate that commercial, washed woven textile cloth wipes measuring 13.5,'iriches by 15 inches and weighingrY 38V.Vglrarns Vare capable of'absorbing about 4.4 times theirweight of waterwhereas wipes made as last described, measuringg inches by 16.1 inches were capable of absorbing about 17 times their weight in water.
Such textile cloth wipes would absorb about 6 times their weight of oil whereas the described product would ab sorb about 10.8 times its weight in oil.
The described improved disposable, but not necessarily single use wipes, compare very favorably with commercial textile cloth wipes in respect of limpness and conformability to objects, and handle much like the cloth wipes. The surface characteristics of the material cause the product to slide very easily across a surface being wiped and the high absorbing capacity and high absorbing rate of paper wadding enable wipes made of the described sheeting to pick up or absorb liquids and dirt or other foreign matter in an advantageous manner as compared with the action of commercial cloth wipes.
Various changes in the described constructions may be made while retaining the principles involved therein.
1. An absorbent `wiping sheet comprising a layer of absorbent material formed of a plurality of interbonded plies of crepe tissue paper of such thickness and con* struction that said layer may be folded and rumpled like textile cloth and tends to disintegrate under rubbing action, and a protective grille on an exposed face of said absorbent layer, said grille comprising a non-woven open mesh netting of low twist, continuous multi-lament threads, said threads having a twist less than 6 turns per inch and being of a denier within the range of about 30 to 150, the filaments being of a denier of from about l to 15, and the threads of said grille which extend in one direction being coated with an adhesive to thereby bond such threads to the threads extending transversely thereof at their crossings and to bond said grille to said absorbent layer, and said threads being flattened at said crossings to thereby enlarge the areas of bonding between the threads and increase the exibility and smoothness of the sheet.
2. An absorbent wiping sheet comprising a layer of absorbent material formed of a plurality of interbonded plies of crepe tissue paper of such thickness and construction that said layer may be folded and rumpled like textile cloth and tends to disintegrate under rubbing action, and a protective `grille on an exposed face of said absorbent layer, said grille comprising a non-woven open mesh netting of low twist, continuous multi-lament threads, said threads having a twist less than 6 turns per inch and being of a denier within the range of about 30 to 150, the filaments being of a denier of from about 1 to l5, a non-Woven facing of fibers intermediate said grille and said exposed face of said absorbent layer, and the threads of said grille which extend in one direction being coated `with an adhesive to thereby bond such threads to the threads extending transversely thereof at their cross ings and to bond said grille and said non-wolven facing of fibers to said absorbent layer, said transverse threads being essentially free of adhesive except at said crossings, and said threads being flattened at said crossings to thereby enlarge the areas of bonding between the threads and increase the ilexibility and smoothness of the sheet.
3. An absorbent wiping sheet comprising a layer of absorbent material formed of a plurality of interbonded plies of crepe tissue paper of such thickness and construction that said layer may be folded and rumpled like textile cloth and tends to disintegrate under rubbing action, said plies being bonded together by a series of adhesive coated threads intermediate said plies, and a protective grille on an exposed face of said absorbent layer, said grille comprising a non-woven open mesh netting of low twist, continuous multi-filament threads, said threads having Ia twist less than 6 turns per inch and being of a denier within the range of about 30 to 150, the laments being of a denier of from about 1 to 15, and the threads of said grille which extend in one direction being coated with an adhesive to thereby bond such threads to the threads extending transversely thereof at their crossings and to bond said grille to said absorbent layer, said transverse threads being essentially free of adhesive except at said crossings, and said threads being lattened at said crossings to thereby enlarge the areas of bonding between the threads and increase the flexibility and smoothness of the sheet.
4. An absorbent wiping sheet comprising a sheet of absorbent material formed by a layer of fluff disposed between a plurality of interbonded plies of crepe tissue paper and being of such thickness and construction that said layer of absorbent material may be folded and rum-pled like textile cloth and tends to disintegrate under rubbing action, said fluff and crepe tissue plies being bonded together by embossing, and a protective grille on an exposed face of said absorbent sheet, said grille compn'sing a non-woven open mesh netting of low twist, continuous multi-filament threads, said threads having a twist less than 6 turns per inch and being of a denier within the range of about 30 to 150, the laments being of a denier of from about 1 to 15, and the 'threads of Said grille which extend in one direction being coated with an adhesive to thereby bond such threads to the threads extending transversely thereof at their crossings and to bond said grille to said absorbent layer, and said threads being flattened at said crossings to thereby enlarge the areas of bonding between the threads and increase the flexibility and smoothness of the sheet.
References Cited in the file of this patent UNITED STATES PATENTS 970,971 Thompson Sept. 20, 1910 1,834,556 Toles Dec. 1, 1931 2,213,290 Rowe Sept. 3, 1940 2,266,761 Jackson et al. Dec. 23, 1941 2,294,898 Fourness et al. Sept. 8, 1942 2,295,439 Voightman Sept. 8, 1942 2,564,689 Harwood et al. Aug. 21, 1951 2,610,936 Carlson Sept. 16, 1952 2,680,469 Ahier et al. June 8, 1954 2,696,243 Holland Dec. 7, 1954 2,719,804 Carlson Oct. 4, 1955 2,725,323 Chadwick et al Nov. 19, 1955 2,739,092 Stevenson Mar. 20, 1956 FOREIGN PATENTS 416,830 Great Britain Sept. 21, 1934 463,256 Great Britain Mar. 25, 1937 693,711 Great Britain Inly 8, 1953
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