TH61377A - Absorbent material with improved adsorption properties. - Google Patents

Abstract

DC60 (25/10/45) A fiber-based absorbent foam compound consisting of a fluid intake capacity of at least 15 g/g, a vertical absorption distance of at least 10 cm, and absorption under zero load of at least 15 g/g. The fiber-based absorbent foam compound consists of insoluble fiber material and a special absorbent material. The fiber-based absorbent foam compound is produced by creating a slurry of water, insoluble fibers, and a binder. The insoluble but water-swelling special absorbent material is added to the slurry, and the temperature is lowered until it freezes. Afterward, the frozen water is removed by a sublimation process, and the fiber-based absorbent foam is recovered. The gelation time, which represents the absorption rate of the special absorbent fluid during preparation, is crucial for producing a uniform absorbent foam that is dried by freezing and can be optimized by various mixing conditions and physical and chemical treatments of the special absorbent. The fiber-based absorbent foam compound consists of a fluid intake capacity of at least 15 g/g. The absorption rate must be at least 15 g/g, the vertical absorption distance must be at least 10 cm, and the absorption under zero load must be at least 15 g/g. The absorbent fiber foam compound consists of insoluble fibrous material and a special absorbent material. The absorbent fiber foam compound is produced by creating a slurry of water, insoluble fibers, and a binder. The insoluble but water-swelling special absorbent material is added to the slurry, and the temperature is lowered until it freezes. Afterward, the frozen water is removed by a sublimation process, and the absorbent fiber foam is recovered. The gelation time, which represents the absorption rate, and the fluidity of the special absorbent during preparation are crucial for producing a uniform absorbent foam that is then dried by freezing. This can be optimized by various mixing conditions and physical and chemical treatments of the special absorbent.

Claims (83)

1. Absorbent fiber foam, consisting of: non-soluble fibers; and special absorbent material; the absorbent fiber foam must have a fluid intake capacity of at least 15 g/g, a vertical absorption distance of at least 10 cm, and absorption under zero load of at least 15 g/g. 2. The absorbent fiber foam of claim 1 consists of approximately 10 to 80% by weight of the special absorbent material, where the percentage by weight is based on the total weight of the absorbent fiber foam. 3. The absorbent fiber foam of claim #2 consists of approximately 20 to 70% by weight of the special absorbent material, where the percentage by weight is based on the total weight of the absorbent fiber foam. 4. The absorbent fiber foam of claim number 3 consists of approximately 30 to 60% by weight of the special absorbent material, where the percentage by weight is based on the total weight of the absorbent fiber foam. 5. The absorbent fiber foam of claim 1 consists of approximately 20 to 90% by weight of insoluble fibers, where the percentage by weight is based on the total weight of the absorbent fiber foam. 6. Absorbent fiber foam of claim number 5, consisting of approximately 30 to 80% by weight of insoluble fibers, where the percentage by weight is based on the total weight of the absorbent fiber foam. 7. The absorbent fiber foam of claim number 6 consists of approximately 40 to 70% by weight of insoluble fibers, where the percentage by weight is based on the total weight of the absorbent fiber foam. 8. Fiber foam for absorption under claim 1, additionally incorporating a binder. 9. Fiber foam for absorption under claim 8, consisting of approximately 0 to 20% by weight of the binder, where the percentage by weight is based on the total weight of the fiber foam for absorption. 10. Fiber foam for absorption under claim 9, consisting of approximately 2 to 10% by weight of the binder, where the percentage by weight is based on the total weight of the fiber foam for absorption. 11. A fibrous foam absorbent under Patent 1, where the foam has a density less than 0.01 g/cm³. 12. A fibrous foam absorbent under claim 11, whereby the foam shall have a density of less than 0.01 to 0.1 g/cm³ of foam. 13. The absorbent fibrous foam of Patent 1 is a dense foam consisting of a density of approximately 0.2 to 0.5 g/cm³. 14. The method for producing low-density fibrous absorbent composites consists of the following steps: formation of a slurry containing water and insoluble fibers; filling the slurry with absorbent material that has a gelation time of at least 40 seconds; cooling the slurry to a temperature between approximately -70°C and 0°C at a cooling rate that affects freezing; complete removal of the frozen water from the slurry; and recovery of the fibrous absorbent foam. 15. The method of claim number 14 states that the slurry consists of approximately 1 to 10% by weight of insoluble fibers based on the total weight of the solution. 16. The method of claim number 14, which includes an additional 0.001 to 5% by weight of the binding agent based on the total weight of the solution. 17. The method of claim number 14 in which the absorbent material consists of a special absorbent material that is insoluble in water but can swell in water. 18. The method of claim number 17 states that the absorbent fiber foam consists of approximately 10 to 80% by weight of the special absorbent material, based on the total weight of the absorbent fiber foam. 19. The method of claim number 18 states that the absorbent fiber foam consists of approximately 20 to 70% by weight of the special absorbent material, based on the total weight of the absorbent fiber foam. 20. The method of claim number 19 states that the absorbent fiber foam consists of approximately 30 to 60% by weight of the special absorbent material, based on the total weight of the absorbent fiber foam. 21. The method of claim 14 states that the absorbent fiber foam shall consist of insoluble fibers in an amount by weight of approximately 20 to 90% by weight, based on the total weight of the absorbent fiber foam. 22. The method of claim number 21 states that the absorbent fiber foam consists of approximately 30 to 80% by weight of insoluble fibers, based on the total weight of the absorbent fiber foam. 23. The method of claim number 22 states that the absorbent fiber foam consists of approximately 40 to 70% by weight of insoluble fibers, based on the total weight of the absorbent fiber foam. 24. The method of claim number 16 states that the absorbent fiber foam contains approximately 0 to 20% by weight of the binder, based on the total weight of the absorbent fiber foam. 25. The method of claim number 24 states that the absorbent fiber foam contains approximately 2 to 10% by weight of the binder, based on the total weight of the absorbent fiber foam. 26. The method of claim 14 stipulates that the absorbent fiber foam shall have a fluid intake capacity of at least 15 g/g, a vertical absorption distance of at least 10 cm, and absorption under zero load shall be at least 15 g/g. 27. The method of claim 14 shall stipulate that the special adsorbent material shall consist of at least one type of crosslinked anionic or cationic polymer selected from a group consisting of sodium-polyacrylate, carboxymethyl cellulose, carboxymethyl polysaccharide, salts of polyaspartic acid, maleic anhydride-isobutylene copolymer, salts of chitosan, salts of polyquaternary ammonium, polyvinyl amine, and combinations of these. 28. The method of claim number 17, in which the special absorbent material consists of a coating of a hydrophobic substance. 29. The method of claim 28, in which the special absorbent material comprises a form chosen from groups of particles, fibers, filaments, non-woven materials, composites, prints, coatings, and combinations of these. 30. The method of claim 28, in which the special absorbent material consists of at least one type of special absorbent particle and special absorbent fiber with a diameter of approximately 100 microns to 1000 microns. 31. The method of claim 28, in which the special adsorbent material consists of a special adsorbent material that is a non-neutralized, non-ionic polymer. 32. The method of claim 28, in which the special absorbent material consists of a coating of a non-absorbent chemical. 33. The method of claim 28, in which the special adsorbent material consists of a special adsorbent material for ion exchange that is not neutralized. 34. The method of Claim 14 is that the water in the slurry has an initial water temperature between 4°C and 23°C. 35. The method of claim 34, where the initial water temperature is approximately 10°C to 23°C. 36. The method of claim No. 14 in which the insoluble fibers consist of at least one type of natural and synthetic fiber. 37. The method of claim 36, in which non-soluble fibers are selected from a group comprising wood pulp fibers, cotton lint fibers, thermoplastic fibers, elastic fibers, rayon fibers, and combinations of these. 38. The method of claim 37 in which thermoplastic fibers are selected from a group consisting of polyethylene, polypropylene, poly(ethylene terephthalate), and combinations thereof. 39. The method of claim 36, in which synthetic fibers are selected from a group consisting of polyvinyl alcohol, polyvinyl chloride, polyacrylonitrile, polyurethane, and combinations of these. 40. Method of claim 36, in which the insoluble fibers consist of hydrophilic fibers. 41. The method of claim 40, in which hydrophilic insoluble fibers are composed of surface-treated hydrophobic fibers. 42. The method of claim 36 states that the diameter of the fibers of the insoluble fibers will be approximately 1 to 100 microns. 43. The method of claim 42, in which the diameter of the fibers of the insoluble fibers is approximately 1 to 50 microns. 44. The method of claim 43 states that the diameter of the fibers of the insoluble fibers is approximately 1 to 30 microns. 45. The method of claim 16 stipulates that the binder is water-soluble before the addition of the special absorbent material and will not be water-soluble after the recovery of the absorbent fiber foam. 46. The method of claim 16, in which the binding agent consists of a polymer with a molecular weight of approximately 10,000 to 10,000,000. 47. The method of claim 46 involves polymers with molecular weights of approximately 100,000 to 1,000,000. 48. The procedure of claim number 45, which includes the addition of a crosslinking agent to the slurry. 49. The method of claim number 14, which states that the temperature is between approximately -70°C and -30°C. 50. The method of claim 49, which states that the temperature is between approximately -70°C and -40°C. 51. The method of claim number 50, which states that the temperature is between approximately -70°C and -50°C. 52. The method of claim 14 in which the rate of cooling is slower than the rate of critical cooling. 53. The method of claim 52, in which the cooling rate is approximately 0.01 °C/min to 10 °C/min. 54. The method of claim number 14, which includes the procedure for crosslinking the absorbent fiber foam. 55. An absorbent product consisting of absorbent fiber foam prepared in accordance with the method of Claim 14. 56. The method of claim 14 in which the foam consists of a density less than approximately 0.01 g of foam/cubic centimeter of foam. 57. The method of claim 56, in which the foam consists of a density of approximately 0.01 to 0.1 g of foam/cubic centimeter of foam. 58. The method of claim number 56, which includes the addition of a denser fibrous foam for absorption. 59. The method of claim 58, in which the densely packed absorbent fiber foam consists of a density of approximately 0.2 to 0.5 g of foam/cubic centimeter of foam. 60. The method for producing fibrous absorbent composites consists of the following steps: the formation of a slurry composed of water, insoluble fibers, and a high molecular weight polymer binder; the addition of a special insoluble but water-swellable absorbent material with a gelation time of at least 40 seconds into the slurry; the cooling of the slurry to a temperature between -70°C and 0°C at a cooling rate sufficient to freeze; the complete removal of the frozen water from the slurry; and the recovery of the fibrous absorbent foam. 61. The method of claim 60 states that slurry consists of approximately 1 to 10% by weight of insoluble fibers based on the weight of the total solution. 62. The method of claim number 60, which includes approximately 0.001 to 5% by weight of the binding agent based on the weight of the total solution. 63. The method of claim 60, in which the absorbent fiber foam consists of a fluid intake capacity of at least 15 g/g, a vertical absorption distance of at least 10 cm, and absorption under zero load of at least 15 g/g. 64. The method of claim 60 states that the special adsorbent material shall contain at least one type of crosslinked anionic or cationic polymer selected from a group consisting of sodium-polyacrylate, carboxymethyl cellulose, carboxymethyl polysaccharide, salts of polyaspartic acid, maleic anhydride-isobutylene copolymer, salts of chitosan, salts of polyquaternary ammonium, polyvinyl amine, and combinations of these. 65. The method of claim 60, in which the binding agent consists of a polymer with a molecular weight of approximately 1,000 to 10,000,000. 66. The method of claim 65, in which the polymer has a molecular weight of approximately 10,000 to 1,000,000. 67. The method of claim number 60, which includes the procedure of adding the crosslinking agent to the solution. 68. The method of claim number 60, where the temperature is approximately -70°C to -30°C. 69. The method of claim number 68, which states that the temperature is between approximately -70°C and -40°C. 70. The method of claim number 69, which states that the temperature is between approximately -70°C and -50°C. 71. The method of claim 60 in which the rate of cooling is slower than the rate of critical cooling. 72. The method of claim 71, in which the cooling rate is approximately 0.01 °C/min to 10 °C/min. 73. The method of claim 67, which includes the crosslinking of the absorbent fiber foam. 74. Diapers, which contain an absorbent fibrous compound, manufactured in accordance with the method of claim 60. 75. Training trousers, containing an absorbent fibrous compound, manufactured according to the method of claim 60. 76. Swimsuits containing absorbent fibrous compounds manufactured in accordance with the method of claim 60. 77. Adult incontinence garments containing an absorbent fibrous compound, manufactured in accordance with the method of claim 60. 78. Feminine hygiene products containing absorbent fibrous compounds manufactured in accordance with the method of claim 60. 79. Medical absorbent products, consisting of fibrous absorbent compounds, manufactured in accordance with the method of claim 60. 80. The method of claim number 60, in which the foam consists of a density less than approximately 0.01 g of foam/cubic centimeter of foam. 81. The method of claim 80, in which the foam consists of a density of approximately 0.01 to 0.1 g of foam/cubic centimeter of foam. 82. The method of claim number 80, which includes the densening of the fibrous foam for absorption. 83. The method of claim 82, in which the densely packed absorbent fiber foam consists of a density of approximately 0.2 to 0.5 g of foam/cubic centimeter of foam.