Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F13/00—Bandages or dressings; Absorbent pads
  • A61F13/15—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators
  • A61F13/53—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators characterised by the absorbing medium
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F13/00—Bandages or dressings; Absorbent pads
  • A61F13/15—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators
  • A61F13/84—Accessories, not otherwise provided for, for absorbent pads
  • A61F13/8405—Additives, e.g. for odour, disinfectant or pH control
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
  • A61L15/00—Chemical aspects of, or use of materials for, bandages, dressings or absorbent pads
  • A61L15/16—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons
  • A61L15/42—Use of materials characterised by their function or physical properties
  • A61L15/46—Deodorants or malodour counteractants, e.g. to inhibit the formation of ammonia or bacteria
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
  • A61L15/00—Chemical aspects of, or use of materials for, bandages, dressings or absorbent pads
  • A61L15/16—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons
  • A61L15/42—Use of materials characterised by their function or physical properties
  • A61L15/60—Liquid-swellable gel-forming materials, e.g. super-absorbents
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F13/00—Bandages or dressings; Absorbent pads
  • A61F13/15—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators
  • A61F13/53—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators characterised by the absorbing medium
  • A61F2013/530481—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators characterised by the absorbing medium having superabsorbent materials, i.e. highly absorbent polymer gel materials
  • A61F2013/530671—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators characterised by the absorbing medium having superabsorbent materials, i.e. highly absorbent polymer gel materials being mixed with mineral or inert material, e.g. "introfying particles"
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F13/00—Bandages or dressings; Absorbent pads
  • A61F13/15—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators
  • A61F13/84—Accessories, not otherwise provided for, for absorbent pads
  • A61F13/8405—Additives, e.g. for odour, disinfectant or pH control
  • A61F2013/8408—Additives, e.g. for odour, disinfectant or pH control with odour control
  • A61F2013/842—Additives, e.g. for odour, disinfectant or pH control with odour control with active charcoal

Definitions

• Odor-inhibiting mixtures for incontinence articles Description The present invention relates to odor-inhibiting mixtures containing water-absorbing polymer particles and spherical activated carbon for use in incontinence articles.
• Water-absorbing polymer particles are used for the production of diapers, tampons, sanitary napkins and other hygiene articles, but also as water-retaining agents in agricultural horticulture.
• the water-absorbing polymer particles are also referred to as superabsorbers.
• the properties of the water-absorbing polymer particles can be adjusted, for example, via the amount of crosslinker used. As the amount of crosslinker increases, the centrifuge retention capacity (CRC) decreases and the absorption under a pressure of 21.0 g / cm 2 (AUL 0.3 psi) goes through a maximum.
• CRC centrifuge retention capacity
• water-absorbing polymer particles are generally surface-postcrosslinked.
• the degree of crosslinking of the particle surface increases, whereby the absorption under a pressure of 49.2 g / cm 2 (AUL0.7 psi) and the centrifuge retention capacity (CRC) can be at least partially decoupled.
• This surface postcrosslinking can be carried out in aqueous gel phase.
• dried, ground and sieved polymer particles base polymer
• Crosslinkers suitable for this purpose are compounds which can form covalent bonds with at least two carboxylate groups of the water-absorbing polymer particles.
• the object of the present invention was to provide improved odor-inhibiting mixtures for use in incontinence articles.
• the mixtures should in particular have a higher degree of whiteness.
• the system components used to produce the odor-inhibiting mixtures should be easy to clean, so that contamination of the subsequent production campaign is avoided when changing products.
• the object was achieved by odor-inhibiting mixtures containing water-absorbing polymer particles and spherical activated carbon.
• Activated carbon is usually used as a powder, broken particles or rod-shaped compacts.
• the spherical activated carbons according to the invention are largely monodisperse spheres.
• the water-absorbing polymer particles are obtained, for example, by polymerization of a monomer solution or suspension comprising a) at least one ethylenically unsaturated, acid group-carrying monomer which may be at least partially neutralized,
• the monomers a) are preferably water-soluble, i. the solubility in water at 23 ° C. is typically at least 1 g / 100 g of water, preferably at least 5 g / 100 g of water, more preferably at least 25 g / 100 g of water, most preferably at least 35 g / 100 g of water.
• Suitable monomers a) are, for example, ethylenically unsaturated carboxylic acids, such as acrylic acid, methacrylic acid, and itaconic acid. Particularly preferred monomers are acrylic acid and methacrylic acid. Very particular preference is given to acrylic acid.
• Suitable monomers a) are, for example, ethylenically unsaturated sulfonic acids, such as styrenesulfonic acid and 2-acrylamido-2-methylpropanesulfonic acid (AMPS).
• sulfonic acids such as styrenesulfonic acid and 2-acrylamido-2-methylpropanesulfonic acid (AMPS).
• AMPS 2-acrylamido-2-methylpropanesulfonic acid
• a suitable monomer a) is, for example, an acrylic acid purified according to WO 2004/035514 A1 with 99.8460% by weight of acrylic acid, 0.0950% by weight of acetic acid, 0.0332% by weight of water, 0.0203% by weight of propionic acid, 0.0001% by weight of furfurale,
• the proportion of acrylic acid and / or salts thereof in the total amount of the monomers is preferably at least 50 mol%, particularly preferably at least 90 mol%, very particularly preferably at least 95 mol%.
• the acrylic acid used usually contains polymerization inhibitors, preferably hydraquinone half ethers, as a storage stabilizer.
• the monomer solution therefore preferably contains up to 250 ppm by weight, preferably at most 130 ppm by weight, more preferably at most 70 ppm by weight, preferably at least
• Hydrochinon protestether each based on the unneutralized acrylic acid.
• an acrylic acid having a corresponding content of hydroquinone half-ether can be used.
• hydroquinone half ethers are hydroquinone monomethyl ether (MEHQ) and / or alpha tocopherol (vitamin E).
• Suitable crosslinkers b) are compounds having at least two groups suitable for crosslinking. Such groups are, for example, ethylenically unsaturated groups which can be radically copolymerized into the polymer chain, and functional groups which can form covalent bonds with the acid groups of the acrylic acid. Furthermore, polyvalent metal salts which can form coordinative bonds with at least two acid groups of the acrylic acid are also suitable as crosslinking agents b).
• Crosslinkers b) are preferably compounds having at least two polymerizable groups which can be incorporated in the polymer network in free-radically polymerized form.
• Suitable crosslinkers b) are, for example, ethylene glycol dimethacrylate, diethylene glycol diacrylate, polyethylene glycol diacrylate, allyl methacrylate, trimethylolpropane triacrylate, triallylamine, tetraallylammonium chloride, tetraallyloxyethane, as described in EP 0 530 438 A1, di- and triacrylates, as in
• Preferred crosslinkers b) are pentaerythritol triallyl ether, tetraallyloxyethane, methylenebismethacrylamide, 15-tuply ethoxylated trimethylolpropane triacrylate, polyethylene glycol diacrylate, trimethylolpropane triacrylate and triallylamine.
• Very particularly preferred crosslinkers b) are the polyethyleneglyoxylated and / or propoxylated glycerols esterified with acrylic acid or methacrylic acid to form diioder triacrylates, as described, for example, in WO 2003/104301 A1.
• di- and / or triacrylates of 3- to 10-fold ethoxylated glycerol are particularly advantageous.
• diacrylates or triacrylates of 1 to 5 times ethoxylated and / or propoxylated glycerol are particularly preferred.
• triacrylates of 3 to 5 times ethoxylated and / or propoxylated glycerol in particular the triacrylate of 3-times ethoxylated glycerol.
• the amount of crosslinker b) is preferably from 0.05 to 1, 5 wt .-%, particularly preferably 0.1 to 1 wt .-%, most preferably 0.2 to 0.6 wt .-%, each based on Acrylic acid.
• CRC centrifuge retention capacity
• initiators c) it is possible to use all compounds which generate free radicals under the polymerization conditions, for example thermal initiators, redox initiators, photoinitiators.
• Suitable redox initiators are sodium peroxodisulfate / ascorbic acid, hydrogen peroxide / ascorbic acid, sodium peroxodisulfate / sodium bisulfite and hydrogen peroxide / sodium bisulfite.
• thermal initiators and redox initiators are used, such as sodium peroxodisulfate / hydrogen peroxide / ascorbic acid.
• the reducing component used is preferably a mixture of the sodium salt of 2-hydroxy-2-sulfinatoacetic acid, the disodium salt of 2-hydroxy-2-sulfonatoacetic acid and sodium bisulfite.
• Such mixtures are available as Brüggolite® FF6 and Brüggolite® FF7 (Brüggemann Chemicals, Heilbronn, Germany).
• Acrylic acid-copolymerizable ethylenically unsaturated monomers d) are, for example, acrylamide, methacrylamide, hydroxyethyl acrylate, hydroxyethyl methacrylate, dimethylaminoethyl methacrylate, dimethylaminoethyl acrylate, dimethylaminopropyl acrylate, diethylaminopropyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate.
• water-soluble polymers e it is possible to use polyvinyl alcohol, polyvinylpyrrolidone, starch, starch derivatives, modified cellulose, such as methylcellulose or hydroxyethylcellulose, gelatin, polyglycols or polyacrylic acids, preferably starch, starch derivatives and modified cellulose.
• an aqueous monomer solution is used.
• the water content of the monomer solution is preferably from 40 to 75% by weight, particularly preferably from 45 to 70% by weight, very particularly preferably from 50 to 65% by weight.
• monomer suspensions ie monomer solutions with excess acrylic acid, for example sodium acrylate, a enforce.
• the preferred polymerization inhibitors require dissolved oxygen for optimum performance. Therefore, the monomer solution can be freed from dissolved oxygen prior to polymerization by inerting, ie, flowing through with an inert gas, preferably nitrogen or carbon dioxide.
• the oxygen content of the monomer solution before polymerization is reduced to less than 1 ppm by weight, more preferably less than 0.5 ppm by weight, most preferably less than 0.1 ppm by weight.
• Suitable reactors are, for example, kneading reactors or belt reactors.
• the polymer gel resulting from the polymerization of an aqueous monomer solution or suspension is continuously comminuted by, for example, counter-rotating stirring shafts, as described in WO 2001/038402 A1.
• the polymerization on the belt is for example in
• a polymer gel is formed, which must be comminuted in a further process step, for example in an extruder or kneader.
• the comminuted polymer gel obtained by means of a kneader may additionally be extruded.
• the acid groups of the polymer gels obtained are usually partially neutralized.
• the neutralization is preferably carried out at the stage of the monomers. This is usually done by mixing the neutralizing agent as an aqueous solution or preferably as a solid.
• the degree of neutralization is preferably from 25 to 95 mol%, particularly preferably from 30 to 80 mol%, very particularly preferably from 40 to 75 mol%, wherein the customary neutralizing agents can be used, preferably alkali metal hydroxides, alkali metal oxides, alkali metal carbonates or Alkalimetallhydrogenkarbonate and mixtures thereof. Instead of alkali metal salts and ammonium salts can be used.
• Sodium and potassium are particularly preferred as alkali metals, but most preferred are sodium hydroxide, sodium carbonate or sodium bicarbonate and mixtures thereof. But it is also possible to carry out the neutralization after the polymerization at the stage of Polymergeis formed during the polymerization. Furthermore, it is possible to neutralize up to 40 mol%, preferably 10 to 30 mol%, particularly preferably 15 to 25 mol%, of the acid groups before the polymerization by adding a part of the neutralizing agent already to the monomer solution and the desired final degree of neutralization only after the polymerization is adjusted at the stage of Polymergeis.
• the polymer gel is preferably mechanically comminuted, for example by means of an extruder, the neutralizing agent being applied. sprayed, sprinkled or infused and then mixed thoroughly. For this purpose, the gel mass obtained can be extruded several times for homogenization.
• the polymer gel is then preferably dried with a belt dryer until the residual moisture content is preferably from 0.5 to 15% by weight, particularly preferably from 1 to 10% by weight, very particularly preferably from 2 to 8% by weight, where Residual moisture content according to the EDANA recommended test method No. WSP 230.2-05 "Mass Loss Upon Heating". If the residual moisture content is too high, the dried polymer gel has too low a glass transition temperature T g and is difficult to process further. If the residual moisture content is too low, the dried polymer gel is too brittle and in the subsequent comminution steps undesirably large amounts of polymer particles having too small a particle size ("fines") are produced. , more preferably from 35 to 70% by weight, most preferably from 40 to 60% by weight. Alternatively, a fluidized bed dryer or a paddle dryer can be used for drying.
• the dried polymer gel is then ground and classified, wherein for grinding usually one- or multi-stage roller mills, preferably two- or three-stage roller mills, pin mills, hammer mills or vibratory mills, can be used.
• an aqueous monomer solution is dripped off and the drops produced are polymerized in a heated carrier gas stream.
• the process steps polymerization and drying can be summarized, as in WO 2008/040715 A2, in WO 2008/052971 A1 and in particular in
• the particle size is adjusted by the size of the drops produced.
• the mean particle size of the water-absorbing polymer particles is preferably at least 200 .mu.m, more preferably from 250 to 600 .mu.m, very particularly from 300 to 500 .mu.m.
• the average particle size can be determined by means of the EDANA recommended test method No. WSP 220.2-05 "Particle Size Distribution", in which the mass fractions of the sieve fractions are applied cumulatively and the average particle size is determined graphically.
• the mean particle size here is the value of the mesh size, which results for accumulated 50 wt .-%.
• the proportion of particles having a particle size of greater than 150 ⁇ m is preferably at least 90% by weight, particularly preferably at least 95% by weight, very particularly preferably at least 98% by weight.
• Polymer particles with too small particle size lower the permeability (SFC). Therefore, the proportion of too small polymer particles ("fines") should be low. Too small polymer particles are therefore usually separated and recycled to the process. This preferably takes place before, during or immediately after the polymerization, ie before the drying of the polymer gel.
• the too small polymer particles can be moistened with water and / or aqueous surfactant before or during the recycling.
• the too small polymer particles are preferably added during the last third of the polymerization.
• the polymer particles which are too small are added very late, for example only in an apparatus downstream of the polymerization reactor, for example an extruder, then the polymer particles which are too small can only be incorporated into the resulting polymer gel with difficulty. Insufficiently incorporated too small polymer particles, however, dissolve again during the grinding of the dried polymer gel, are therefore separated again during classification and increase the amount of recycled too small polymer particles.
• the proportion of particles having a particle size of at most 850 ⁇ m is preferably at least 90% by weight, particularly preferably at least 95% by weight, very particularly preferably at least 98% by weight.
• the proportion of particles having a particle size of 150 to 850 ⁇ m is preferably at least 90% by weight, particularly preferably at least 95% by weight, very particularly preferably at least 98% by weight.
• Polymer particles with too large particle size reduce the swelling rate. Therefore, the proportion of polymer particles too large should also be low.
• the polymer particles can be surface postcrosslinked to further improve the properties.
• Suitable surface postcrosslinkers are compounds containing groups which form covalent bonds with at least two carboxylate groups of the polymer particles can. Examples of suitable compounds are polyfunctional amines, polyfunctional amidoamines, polyfunctional epoxides, as described in EP 0 083 022 A2, EP 0 543 303 A1 and US Pat
• EP 0 937 736 A2 di- or polyfunctional alcohols, as described in DE 33 14 019 A1, DE 35 23 617 A1 and EP 0 450 922 A2, or ⁇ -hydroxyalkylamides, as described in
• Preferred surface postcrosslinkers are ethylene carbonate, ethylene glycol diglycidyl ether, reaction products of polyamides with epichlorohydrin and mixtures of propylene glycol and 1,4-butanediol.
• Very particularly preferred surface postcrosslinkers are 2-hydroxyethyl-2-oxazolidinone, 2-oxazolidinone and 1,3-propanediol.
• surface postcrosslinkers which contain additional polymerizable ethylenically unsaturated groups, as described in DE 37 13 601 A1.
• the amount of surface postcrosslinker is preferably from 0.001 to 2% by weight, particularly preferably from 0.02 to 1% by weight. , very particularly preferably 0.05 to 0.2 wt .-%, each based on the polymer particles.
• polyvalent cations are applied to the particle surface in addition to the surface postcrosslinkers before, during or after the surface postcrosslinking.
• the polyvalent cations which can be used in the process according to the invention are, for example, divalent cations, such as the cations of zinc, magnesium, calcium, iron and strontium, trivalent cations, such as the cations of aluminum, iron, chromium, rare earths and manganese, tetravalent cations, such as the cations of Titanium and zirconium.
• divalent cations such as the cations of zinc, magnesium, calcium, iron and strontium
• trivalent cations such as the cations of aluminum, iron, chromium, rare earths and manganese
• tetravalent cations such as the cations of Titanium and zirconium.
• hydroxide, chloride, bromide, sulfate, hydrogen sulfate, carbonate, bicarbonate, nitrate, phosphate, hydrogen phosphate, dihydrogen phosphate and carboxylate, such as acetate, citrate and lactate are possible.
• salts with different counterions for example basic aluminum salts, such as aluminum monoacetate or aluminum monolactate.
• Aluminum sulfate, aluminum monoacetate and aluminum lactate are preferred.
• polyamines can also be used as polyvalent cations.
• the amount of polyvalent cation used is, for example, 0.001 to 1.5% by weight, preferably 0.005 to 1% by weight, particularly preferably 0.02 to 0.8% by weight. in each case based on the polymer particles.
• the surface postcrosslinking is usually carried out in such a way that a solution of the surface postcrosslinker is sprayed onto the dried polymer particles. Following spraying, the surface postcrosslinker coated polymer particles are thermally dried, with the surface postcrosslinking reaction occurring both before and during drying.
• the spraying of a solution of the surface postcrosslinker is preferably carried out in mixers with moving mixing tools, such as screw mixers, disk mixers and paddle mixers.
• moving mixing tools such as screw mixers, disk mixers and paddle mixers.
• horizontal mixers such as paddle mixers
• vertical mixers very particularly preferred are vertical mixers.
• the distinction between horizontal mixer and vertical mixer is made by the storage of the mixing shaft, i.
• Horizontal mixers have a horizontally mounted mixing shaft and vertical mixers have a vertically mounted mixing shaft.
• Suitable mixers are, for example, Horizontal Pflugschar® mixers (Gebr.
• the surface postcrosslinkers are typically used as an aqueous solution.
• the amount of non-aqueous solvent or total solvent can be used to adjust the penetration depth of the surface postcrosslinker into the polymer particles.
• solvent for example isopropanol / water, 1,3-propanediol / water and propylene glycol / water, the mixing mass ratio preferably being from 20:80 to 40:60.
• the thermal drying is preferably carried out in contact dryers, more preferably paddle dryers, very particularly preferably disk dryers.
• Suitable dryers are, for example, Hosokawa Bepex® Horizontal Paddle Dryer (Hosokawa Micron GmbH;
• the drying can take place in the mixer itself, by heating the jacket or blowing hot air.
• a downstream dryer such as a Hörmann Dryer, a rotary kiln or a heated screw. Particularly advantageous is mixed and dried in a fluidized bed dryer.
• Preferred drying temperatures are in the range 100 to 250 ° C, preferably 120 to 220 ° C, more preferably 130 to 210 ° C, most preferably 150 to 200 ° C.
• the preferred residence time at this temperature in the reaction mixer or dryer is preferably at least 10 minutes, more preferably at least 20 minutes, most preferably at least 30 minutes, and usually at most 60 minutes.
• the water-absorbing polymer particles are cooled after the thermal drying.
• the cooling is preferably carried out in contact coolers, particularly preferably blade coolers, very particularly preferably disk coolers.
• Suitable coolers are, for example, Hosokawa Bepex® Horizontal Paddle Coolers (Hosokawa Micron GmbH, Leingart, Germany), Hosokawa Bepex® Disc Coolers (Hosokawa Micron GmbH, Leingart, Germany), Holo-Flite® coolers (Metso Minerals Industries, Inc., Danville, USA ) and Nara Paddle Cooler (NARA Machinery Europe, Frechen, Germany). Moreover, fluidized bed coolers can also be used.
• the water-absorbing polymer particles to 20 to 150 ° C, preferably 30 to 120 ° C, more preferably 40 to 100 ° C, most preferably 50 to 80 ° C, cooled.
• the surface-postcrosslinked polymer particles can be classified again, wherein too small and / or too large polymer particles are separated and recycled to the process.
• the surface-postcrosslinked polymer particles can be coated or post-moistened for further improvement of the properties.
• the post-wetting is preferably carried out at 30 to 80 ° C, more preferably at 35 to 70 ° C, most preferably at 40 to 60 ° C. If the temperatures are too low, the water-absorbing polymer particles tend to clump together and at higher temperatures water is already noticeably evaporating.
• the amount of water used for the rewetting is preferably from 1 to 10 wt .-%, particularly preferably from 2 to 8 wt .-%, most preferably from 3 to 5 wt .-%.
• the post-humidification is carried out in the cooler after the thermal drying.
• Suitable coatings for improving the swelling rate and the permeability are, for example, inorganic inert substances, such as water-insoluble metal salts, organic polymers, cationic polymers and di- or polyvalent metal cations.
• Suitable coatings for dust binding are, for example, polyols.
• Suitable coating tions against the unwanted caking tendency of the polymer particles are, for example, fumed silica, such as Aerosil® 200, and surfactants, such as Span® 20.
• the water-absorbing polymer particles have a centrifuge retention capacity (CRC) of typically at least 15 g / g, preferably at least 20 g / g, preferably at least 22 g / g, more preferably at least 24 g / g, most preferably at least 26 g / g.
• the centrifuge retention capacity (CRC) of the water-absorbing polymer particles is usually less than 60 g / g.
• Centrifuge Retention Capacity (CRC) is determined according to the EDANA recommended Test Method No. WSP 241.2-05 "Fluid Retention Capacity in Saline, After Centrifugation".
• the mixtures according to the invention preferably contain at least 80% by weight, preferably at least 85% by weight, particularly preferably at least 90% by weight, very particularly preferably at least 95% by weight, of water-absorbing polymer particles.
• the spherical activated carbon can be prepared by pyrolysis of spherical organic material, for example polystyrene. However, it is also possible to pyrolyze glucose solutions, as described in Int. J. Electrochem. Sci., Vol. 4, vintage 2009, pages 1063 to 1073. Suitable spherical activated carbons are also available as SARATECH® 100562, SARATECH® 100772 and SARATECH® 101373 (Blücher GmbH, Erkrath, Germany).
• the spherical activated carbon has a surface area of preferably from 10 to 10,000 m 2 / g, more preferably from 100 to 5,000 m 2 / g, most preferably from 1,000 to 2,000 m 2 / g.
• the mean particle size of the spherical activated carbon is preferably at least
• the mean particle size of the product fraction can be determined by means of the EDANA recommended test method No. WSP 220.2-05 "Particle Size Distribution", in which the mass fractions of the sieve fractions are cumulatively applied and the average particle size is determined graphically.
• the mean particle size here is the value of the mesh size, which results for accumulated 50 wt .-%.
• the proportion of spherical activated carbon having a particle size of 300 to 600 ⁇ m preferably amounts to at least 90% by weight, more preferably at least 95% by weight, very particularly preferably at least 98% by weight.
• the mixtures according to the invention preferably contain at least 0.1% by weight, more preferably at least 0.5% by weight, preferably at least 1% by weight, very preferably at least 5% by weight, of spherical activated carbon.
• the type of mixing is not restricted and can already be used in the preparation of the water-absorbing polymer particles, for example when cooling according to the surface conditions. post-crosslinking or subsequent classification, or in a special mixer. Suitable mixers have already been described above in the surface postcrosslinking of the water-absorbing polymer particles.
• the present invention is based on the finding that spherical activated carbon has a high abrasion resistance and is present in the mixtures according to the invention in isolation next to the water-absorbing polymer particles. The formation of fine dust or coloring of the water-absorbing polymer particles by abrasion is avoided.
• the odor-inhibiting mixtures may additionally contain metal peroxides, oxidases and / or zeolites.
• the metal peroxide is preferably the peroxide of a metal of FIG. Main group, the 2.
• Main group and / or the 2nd subgroup of the Periodic Table of the Elements particularly preferably the peroxide of a metal of the 2nd subgroup of the Periodic Table of the Elements.
• Suitable metal peroxides are, for example, lithium peroxide, strontium peroxide, barium peroxide, sodium peroxide, magnesium peroxide and calcium peroxide, particularly preferably zinc peroxide.
• the mixture according to the invention preferably contains from 0.001 to 5% by weight, preferably from 0.01 to 3% by weight, particularly preferably from 0.1 to 1.5% by weight, very particularly preferably from 0.2 to 0, 8 wt .-%, of the metal peroxide.
• Metal peroxides in particular zinc peroxide, have a good odor-inhibiting effect and the mixtures prepared therewith have a high storage stability.
• the mixtures preferably contain less than 1 ppm, more preferably less than 10 ppm, most preferably less than 5 ppm, heavy metal ions.
• Heavy metal ions in particular iron ions, lead to the catalytic decomposition of the metal peroxides and thus reduce the storage stability of the mixtures.
• Suitable zeolites are, for example, zeolites with cations of the 1. Main group, the 2nd main group, the 1st Subgroup and / or the 2nd subgroup of the Periodic Table of the Elements.
• Suitable cations are, for example, zinc cations, silver cations and copper cations, particularly preferably titanium cations.
• the mixture according to the invention preferably contains from 0.001 to 5% by weight, preferably from 0.01 to 3% by weight, particularly preferably from 0.1 to 1.5% by weight, very particularly preferably from 0.2 to 0, 8% by weight of the zeolite. Zeolites also have a good odor-inhibiting effect.
• Suitable oxidases are oxidases of the group EC 1 .1.3.x, such as glucose oxidases (EC number 1 .1 .3.4), the group EC 1 .3.3.x, such as bilirubin oxidases (EC number 1.3.3.5), the group EC 1 .4.3.x, such as glycine oxidases (EC number 1.4.3.19), group EC 1.5.3.x, such as polyamine oxidases (EC number 1.5.3.1 1), group EC 1.6.3.x, such as NAD (P) H-oxidases (EC number 1 .6.3.1), the group EC 1.7.3.x, such as hydroxylamine oxidases (EC number 1.7.3.4), the group EC 1.8.3.x, such as sulfite oxidases (EC No.
• the group EC 1 .8.3.1 such as cytochrome xidases (EC No. 1 .9.3.1), the group EC 1 .10.3.x, such as catechol oxidases (EC No. 1. 10.3.1), group EC 1.16.3.x, such as ferroxidase (EC number 1.16.3.1), group EC
• 1 .17.3.x such as xanthine oxidases (EC number 1.17.3.2), and the group EC 1 .21 .3.z, such as reticulin oxidases (EC number 1 .21.3.3).
• a glucose oxidase (EC number 1.1.3.4) is used. It is even more advantageous if the glucose oxidase contains very little or no catalase (EC number 1 .1 1 .1 .6).
• the specific catalytic oxidase activity of the odor-inhibiting mixture is preferably from 0.01 to 1, 000 g ⁇ substrate _1 min -1, more preferably from 0.1 to
• substrate g _1 min -1 100 ⁇ substrate g _1 min -1 , most preferably from 1 to 10 ⁇ substrate g _1 -min -1 .
• the specific catalytic oxidase activity of the mixture can be determined by conventional methods. However, it is better to determine the catalytic activity of the oxidase itself and to calculate the specific catalytic oxidase activity of the mixture by calculation. Oxidases can reduce unpleasant odors, especially unpleasant odors caused by sulfur compounds. This may be due to hydrogen peroxide generated as a result of the catalytic oxidase activity. Therefore, the simultaneous use of peroxidases should be avoided.
• the odor-inhibiting mixtures may additionally contain the substrate of the oxidase.
• a Substart is a compound that is converted by the enzyme in a chemical reaction.
• the first step in an enzymatic reaction is the formation of an enzyme-substrate complex, which after the reaction leads to the release of product and enzyme, so that the catalytic cycle can be run through again.
• An enzyme can possibly convert several different substrates, which are often chemically similar.
• Substrates in the context of the present invention are substrates of the oxidases which can be used according to the invention, for example ⁇ -D-glucose for glucose oxidase.
• the substrates can also be used encapsulated so that they are available only when adding liquid of the oxidase, for example by coating with water-soluble polymers such as polyvinyl alcohol. However, it is also possible instead or in addition to encapsulate the oxidases to be used according to the invention.
• a further subject of the present invention are hygiene articles containing a mixture according to the invention, in particular hygiene articles for light and severe incontinence.
• the sanitary articles usually contain a water-impermeable back, a water-permeable upper side and in between an absorbent core of the water-absorbing polymer particles according to the invention and fibers, preferably cellulose.
• the proportion of the water-absorbing polymer particles according to the invention in the absorbent core is preferably from 20 to 100% by weight, preferably from 50 to 100% by weight.
• the residual monomer content of the water-absorbing polymer particles is determined according to the EDANA-recommended test method WSP No. 210.2-05 "Residual Monomers”.
• the moisture content of the water-absorbing polymer particles is determined according to the test method No. WSP 230.2-05 "Mass Loss Upon Heating" recommended by EDANA.
• Centrifuge Retention Capacity is determined according to the EDANA recommended Test Method No. WSP 241.2-05 "Fluid Retention Capacity in Saline, After Centrifugation". Absorption under a pressure of 49.2 g / cm 2 (absorption under load)
• the absorption under a pressure of 49.2 g / cm 2 (AUL0.7 psi) is determined analogously to the EDANA recommended test method no. WSP 242.2-05 "Absorption Under Pressure, Gravimetric Dermatation", whereby instead of a pressure of 21 , 0 g / cm 2 (AUL0.3psi) a pressure of 49.2 g / cm 2 (AUL0.7psi) is set.
• CIE color number (L, a, b)
• the values for a and b indicate the position of the color on the red / green and yellow / blue color axes, where + a stands for red, -a for green, + b for yellow, and -b for blue
• HC60 L-3b the HC60 value is calculated.
• the color measurement corresponds to the tristimulus method according to DIN 5033-6.
• the water-absorbing polymer particles were subsequently analyzed.
• the content of residual monomer was 4,500 ppm, the moisture content 5.7% by weight, the centrifuge retention capacity (CRC) 33.7 g / g and the absorption under pressure (AUL0.7 psi) 22.7 g / g.
• Example 2 (not according to the invention) 270 g of water-absorbing polymer particles from example 1 and 13.5 g of activated carbons of the Activarbone 3S type (CECA, La Garenne Colombes, France) were weighed into a 500 ml plastic square bottle. This mixture was homogenized for 15 minutes at 49 rpm in a tumble mixer and analyzed. The results are summarized in Table 1 (Sample A). Then the 500ml plastic square bottle was emptied and not cleaned. Again, 270 g of water-absorbing polymer particles from Example 1 were weighed, but no activated carbon. This mixture was also homogenized for 15 minutes at 49 rpm in a tumble mixer and analyzed. The results are summarized in Table 1 (Sample B). Example 3
• Example A 270 g of water-absorbing polymer particles from Example 1 and 13.5 g of spherical activated carbon of the type SARATECH® 100562 (Blücher GmbH, Erkrath, Germany) were weighed into a 500 ml plastic square bottle. This mixture was homogenized for 15 minutes at 49 rpm in a tumble mixer and analyzed. The results are summarized in Table 1 (Sample A).
• Hysorb® B7055 BASF SE, Ludwigshafen, DE
• sodium acrylate-based surface-postcrosslinked water-absorbing polymer particles having a degree of neutralization of 70 mol% Such surface-postcrosslinked water-absorbing polymer particles are available, for example, from BASF Aktiengesellschaft (trade name HySorb®), from Stockhausen GmbH (trade name Favor®) and from Nippon Shokubai Co., Ltd. (Trade name Aqualic®) commercially available.

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• 2012
  • 2012-05-31 WO PCT/EP2012/060200 patent/WO2012163995A1/de active Application Filing
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