US20120064792A1 - Water Absorbent Storage Layers - Google Patents
Water Absorbent Storage Layers Download PDFInfo
- Publication number
- US20120064792A1 US20120064792A1 US13/319,591 US201013319591A US2012064792A1 US 20120064792 A1 US20120064792 A1 US 20120064792A1 US 201013319591 A US201013319591 A US 201013319591A US 2012064792 A1 US2012064792 A1 US 2012064792A1
- Authority
- US
- United States
- Prior art keywords
- water
- polymer particles
- absorbing
- weight
- liquid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Images
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
- A61F13/531—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 a homogeneous composition through the thickness of the pad
- A61F13/532—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 a homogeneous composition through the thickness of the pad inhomogeneous in the plane of the pad
- A61F13/5323—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 a homogeneous composition through the thickness of the pad inhomogeneous in the plane of the pad having absorbent material located in discrete regions, e.g. pockets
-
- 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
- A61F13/51—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 outer layers
- A61F13/511—Topsheet, i.e. the permeable cover or layer facing the skin
-
- 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
- A61F13/51—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 outer layers
- A61F13/514—Backsheet, i.e. the impermeable cover or layer furthest from the skin
- A61F13/51401—Backsheet, i.e. the impermeable cover or layer furthest from the skin characterised by the material
-
- 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
- A61F13/53—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
- A61F13/539—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 characterised by the connection of the absorbent layers with each other or with the outer layers
-
- 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
- A61L15/22—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons containing macromolecular materials
-
- 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
- A61L15/22—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons containing macromolecular materials
- A61L15/24—Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds; Derivatives thereof
-
- 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
- A61L15/22—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons containing macromolecular materials
- A61L15/26—Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds; Derivatives thereof
-
- 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
- A61L15/22—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons containing macromolecular materials
- A61L15/28—Polysaccharides or their derivatives
-
- 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
-
- 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
- A61L15/425—Porous materials, e.g. foams or sponges
-
- 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
- A61L15/58—Adhesives
-
- 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
- A61F13/531—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 a homogeneous composition through the thickness of the pad
-
- 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
- A61F2013/530007—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 being made from pulp
-
- 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
- A61F2013/530131—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 being made in fibre but being not pulp
-
- 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
-
- 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
- A61F2013/530802—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 characterized by the foam or sponge other than superabsorbent
-
- 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
- A61F13/539—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 characterised by the connection of the absorbent layers with each other or with the outer layers
- A61F2013/53908—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 characterised by the connection of the absorbent layers with each other or with the outer layers with adhesive
- A61F2013/53933—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 characterised by the connection of the absorbent layers with each other or with the outer layers with adhesive with water-soluble binder
- A61F2013/53941—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 characterised by the connection of the absorbent layers with each other or with the outer layers with adhesive with water-soluble binder being alcohol-based binder
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T442/00—Fabric [woven, knitted, or nonwoven textile or cloth, etc.]
- Y10T442/60—Nonwoven fabric [i.e., nonwoven strand or fiber material]
- Y10T442/699—Including particulate material other than strand or fiber material
Definitions
- the present invention relates to improved water-absorbing storage layers for use in hygiene articles, the water-absorbing storage layers being essentially free of cellulose fibers.
- water-absorbing polymer particles and the use thereof for producing hygiene articles is described, for example, in the monograph “Modern Superabsorbent Polymer Technology”, F. L. Buchholz and A. T. Graham, Wiley-VCH, 1998, especially on pages 252 to 258.
- the water-absorbing polymer particles are also referred to as superabsorbents.
- the currently commercially available disposable diapers consist typically of a liquid-pervious topsheet (A), a liquid-impervious backsheet (B), a water-absorbing storage layer (C) between layers (A) and (B), and an acquisition distribution layer (D) between layers (A) and (C).
- the water-absorbing storage layer consists typically of a mixture of water-absorbing polymer particles and cellulose fibers, the water-absorbing polymer particles being fixed by the cellulose matrix.
- WO 97/17397 A1 describes a process for producing water-absorbing foams. Use of such foams allows the use of cellulose fibers to be dispensed with entirely.
- Cellulose-free hygiene articles can also be secured to suitable nonwoven backsheets by fixing of water-absorbing polymer particles by means of thermoplastic polymers, especially of hotmelt adhesives, provided that these thermoplastic polymers are spun out to form fine fibers.
- the improved water-absorbing storage layers should be possible to use the customary water-absorbing polymer particles.
- the improved water-absorbing storage layers should be essentially free of cellulose fibers, and the water-absorbing polymer particles in the water-absorbing storage layer should neither slip nor fall out either in the dry or moist state.
- free of cellulose fibers means that the cellulose content in the inventive storage layer is preferably less than 30% by weight, preferentially less than 20% by weight, more preferably less than 10% by weight, most preferably less than 5% by weight. Ideally, no cellulose at all is present.
- the object is achieved by water-absorbing storage layers consisting of a nonwoven backsheet, water-absorbing polymer particles and a liquid-pervious topsheet, wherein the water-absorbing polymer particles are fixed on the nonwoven backsheet.
- the liquid-pervious topsheet is adhesive bonded to the nonwoven backsheet to form pockets.
- customary adhesives can be used.
- the liquid-pervious topsheet and/or nonwoven backsheet is entirely or partly composed of a thermoplastic polymer, and the liquid-pervious topsheet is adhesive bonded to the nonwoven backsheet by partial melting.
- Suitable nonwoven backsheets may consist of mixtures of thermoplastic fibers (for example polyolefins, polyesters, polyamides) and non-thermoplastic fibers (for example cellulose).
- pockets filled with water-absorbing polymer particles imparts the form of a quilt to the water-absorbing storage layer.
- the water-absorbing polymer particles are prevented from slipping within the water-absorbing storage layer by the pockets.
- the depressions are partly filled with a liquid-conducting filler material and the pockets are optionally also additionally covered thereby.
- Useful filler materials for this purpose include hydrophilic fibers alone (for example cellulose, viscose or rayon) or in a mixture with other fibers (for example propylene or cellulose acetate).
- the fibers may also be those which consist of more than one component and which have a bi- or multilamellar or hollow cross section. Such fibers typically conduct the liquid better than simple smooth fibers.
- the depressions formed in the water-absorbing storage layer by virtue of the adhesive bonding of the liquid-pervious topsheet to the nonwoven backsheet are filled with further water-absorbing polymer particles and fixed to a further liquid-pervious topsheet.
- FIGS. 1 a and 1 b show cross sections, and FIG. 1 c shows a longitudinal section, of the inventive water-absorbing storage layers of the first embodiment, the reference numerals having the following meanings:
- a nonwoven substrate with preferably hydrophilic fibers protruding upward is used.
- the water-absorbing polymer particles are fixed by the fibers between the nonwoven backsheet and the liquid-pervious topsheet.
- the liquid-pervious topsheet is preferably adhesive bonded to the fibers of the nonwoven backsheet.
- the fibers protruding upward may consist of all known polymers and mixtures thereof, but preference is given to polyolefins, polyesters, polyurethanes, cellulose and derivatives thereof, polyamides.
- the fibers may also be those which consist of more than one component and which have a bi- or multilamellar or hollow cross section.
- FIG. 2 shows a cross section of the inventive water-absorbing storage layers of the second embodiment, the reference numerals having the following meanings:
- a soft matrix composed of a liquid-pervious material is applied to the nonwoven backsheet, and the water-absorbing polymer particles are introduced into the chambers of the matrix.
- the chambers of the matrix are sealed with a liquid-pervious topsheet.
- the soft matrix is preferably adhesive bonded to the nonwoven backsheet and the liquid-pervious topsheet.
- the matrix material can be selected such that it additionally promotes liquid distribution within the water-absorbing storage layer.
- Suitable for this purpose are pressed hydrophilic fibers (for example of cellulose, chemically precipitated cellulose or crosslinked cellulose), or open-pore soft sponges. In the case of sponges, hydrophilic types are preferred.
- the matrix material should have, in the expanded state (unpressed), continuous pores with diameter preferably of 0.001 to 2.0 mm, preferably of 0.01 to 1.0 mm, more preferably of 0.03 to 0.5 mm, most preferably of 0.06 to 0.3 mm.
- FIG. 3 a shows a top view
- FIG. 3 b shows cross sections, of the inventive water-absorbing storage layers of the third embodiment, the reference numerals having the following meanings:
- a water-soluble adhesive for dry fixing of the water-absorbing polymer particles.
- the adhesive is applied, for example, to the nonwoven backsheet before the application of the water-absorbing polymer particles.
- the application can be effected, for example, in punctiform fashion, over the whole area, or preferably in strips in or transverse to or diagonally with respect to the machine running direction.
- the water-soluble adhesive may consist, for example, of polyvinyl alcohol, polyvinylpyrrolidone, polyethylene glycol, starch and starch derivatives, cellulose and cellulose derivatives, or polyacrylic acid.
- the water-soluble adhesive comprises at least one polyamine or consists thereof.
- Suitable polyamines are polyvinylamines, polyethyleneimines, polyallylamines. Particular preference is given to polyvinylamine. On contact with moisture, the amine is released from the adhesive and becomes attached to the swelling hydrogel, which additionally causes a particular gel layer stability in the swollen state.
- a web of the nonwoven backsheet is moved in machine direction, and strips or geometric patterns comprising water-absorbing polymer particles are applied thereto.
- a continuous surface may be obtained in this way.
- any desired geometric forms and patterns are conceivable, for example one which are arranged like cushions comprising water-absorbing polymer particles in terms of area.
- the cushions or the heaps of water-absorbing polymer particles applied may assume any desired shape in terms of area, for example circles, ellipses, rectangles, squares, triangles (viewed from above).
- Particular preference is given to any desired polygons or mixtures of polygons with which the two-dimensional surface can be covered without gaps.
- Particular preference is also given to the application of one or more continuous strips in machine running direction, the strips running parallel to one another.
- an elastic nonwoven can also be used as a topsheet or as a backsheet. Such nonwovens are commercially available.
- the nonwoven backsheet is fixed on a suitable machine by means of reduced pressure such that water-absorbing polymer particles to be laid on can then be laid on there by means of masks or similar means, such that these water-absorbing polymer particles are held fixed from below by the existing suction during processing. It is thus equally possible to temporarily fix the other components.
- the water-absorbing polymer particles are produced by polymerizing a monomer solution or suspension and are typically water-insoluble.
- the monomers a) are preferably water-soluble, i.e. 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
- Impurities can have a considerable influence on the polymerization.
- the raw materials used should therefore have a maximum purity. It is therefore often advantageous to specially purify the monomers a). Suitable purification processes are described, for example, in WO 2002/055469 A1, WO 2003/078378 A1 and WO 2004/035514 A1.
- a suitable monomer a) is, for example, acrylic acid purified according to WO 2004/035514 A1 comprising 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 furfurals, 0.0001% by weight of maleic anhydride, 0.0003% by weight of diacrylic acid and 0.0050% by weight of hydroquinone monomethyl ether.
- the proportion of acrylic acid and/or salts thereof in the total amount of monomers a) is preferably at least 50 mol %, more preferably at least 90 mol %, most preferably at least 95 mol %.
- the monomers a) typically comprise polymerization inhibitors, preferably hydroquinone monoethers, as storage stabilizers.
- the monomer solution comprises preferably up to 250 ppm by weight, preferably at most 130 ppm by weight, more preferably at most 70 ppm by weight, preferably at least 10 ppm by weight, more preferably at least 30 ppm by weight, especially around 50 ppm by weight, of hydroquinone monoether, based in each case on the unneutralized monomer a).
- the monomer solution can be prepared by using an ethylenically unsaturated monomer bearing acid groups with an appropriate content of hydroquinone monoether.
- hydroquinone monoethers 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 polymerized free-radically into the polymer chain, and functional groups which can form covalent bonds with the acid groups of the monomer a). In addition, polyvalent metal salts which can form coordinate bonds with at least two acid groups of the monomer a) are also suitable as crosslinkers b).
- Crosslinkers b) are preferably compounds having at least two polymerizable groups which can be polymerized free-radically into the polymer network.
- 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 described in EP 0 547 847 A1, EP 0 559 476 A1, EP 0 632 068 A1, WO 93/21237 A1, WO 2003/104299 A1, WO 2003/104300 A1, WO 2003/104301 A1 and DE 103 31 450 A1, mixed acrylates which, as well as acrylate groups, comprise further ethylenically unsaturated groups, as described in DE 103 31 456 A1 and DE
- Preferred crosslinkers b) are pentaerythrityl triallyl ether, tetraalloxyethane, methylenebismethacrylamide, 15-tuply ethoxylated trimethylolpropane triacrylate, polyethylene glycol diacrylate, trimethylolpropane triacrylate and triallylamine.
- Very particularly preferred crosslinkers b) are the polyethoxylated and/or -propoxylated glycerols which have been esterified with acrylic acid or methacrylic acid to give di- or triacrylates, as described, for example, in WO 2003/104301 A1.
- Di- and/or triacrylates of 3- to 10-tuply ethoxylated glycerol are particularly advantageous.
- di- or triacrylates of 1- to 5-tuply ethoxylated and/or propoxylated glycerol are particularly advantageous.
- Most preferred are the triacrylates of 3- to 5-tuply ethoxylated and/or propoxylated glycerol, especially the triacrylate of 3-tuply ethoxylated glycerol.
- the amount of crosslinker b) is preferably 0.05 to 1.5% by weight, more preferably 0.1 to 1% by weight, most preferably 0.3 to 0.6% by weight, based in each case on monomer a). With rising crosslinker content, the centrifuge retention capacity (CRC) falls and the absorption under a pressure of 21.0 g/cm 2 passes through a maximum.
- CRC centrifuge retention capacity
- the initiators c) used may be 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. Preference is given to using mixtures of thermal initiators and redox initiators, such as sodium peroxodisulfate/hydrogen peroxide/ascorbic acid.
- the reducing component used is, however, 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 obtainable as Bruggolite® FF6 and Bruggolite® FF7 (Bruggemann Chemicals; Heilbronn; Germany).
- Ethylenically unsaturated monomers d) copolymerizable with the ethylenically unsaturated monomers a) bearing acid groups are, for example, acrylamide, methacrylamide, hydroxyethyl acrylate, hydroxyethyl methacrylate, dimethylaminoethyl methacrylate, dimethylaminoethyl acrylate, dimethylaminopropyl acrylate, diethylaminopropyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate.
- the water-soluble polymers e) used may be 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, more preferably from 45 to 70% by weight, most preferably from 50 to 65% by weight.
- monomer suspensions i.e. monomer solutions with excess monomer a), for example sodium acrylate. With rising water content, the energy requirement in the subsequent drying rises, and, with falling water content, the heat of polymerization can only be removed inadequately.
- the preferred polymerization inhibitors require dissolved oxygen.
- the monomer solution can therefore be freed of dissolved oxygen before the polymerization by inertization, i.e. flowing an inert gas through, preferably nitrogen or carbon dioxide.
- the oxygen content of the monomer solution is preferably lowered before the polymerization to less than 1 ppm by weight, more preferably to less than 0.5 ppm by weight, most preferably to less than 0.1 ppm by weight.
- Suitable reactors are, for example, kneading reactors or belt reactors.
- the polymer gel formed in the polymerization of an aqueous monomer solution or suspension is comminuted continuously by, for example, contrarotatory stirrer shafts, as described in WO 2001/038402 A1.
- Polymerization on a belt is described, for example, in DE 38 25 366 A1 and U.S. Pat. No. 6,241,928.
- Polymerization in a belt reactor forms a polymer gel, which has to be comminuted in a further process step, for example in an extruder or kneader.
- the comminuted polymer gel obtained by means of a kneader can additionally be extruded.
- the acid groups of the resulting polymer gels have typically been partially neutralized.
- Neutralization is preferably carried out at the monomer stage. This is typically done by mixing in the neutralizing agent as an aqueous solution or preferably also as a solid.
- the degree of neutralization is preferably from 25 to 95 mol %, more preferably from 30 to 80 mol %, most preferably from 40 to 75 mol %, for which the customary neutralizing agents can be used, preferably alkali metal hydroxides, alkali metal oxides, alkali metal carbonates or alkali metal hydrogencarbonates and also mixtures thereof.
- alkali metal salts it is also possible to use ammonium salts.
- Particularly preferred alkali metals are sodium and potassium, but very particular preference is given to sodium hydroxide, sodium carbonate or sodium hydrogencarbonate and also mixtures thereof.
- the polymer gel is neutralized at least partly after the polymerization, the polymer gel is preferably comminuted mechanically, for example by means of an extruder, in which case the neutralizing agent can be sprayed, sprinkled or poured on and then carefully mixed in. To this end, the gel mass obtained can be repeatedly extruded for homogenization.
- the polymer gel is then preferably dried with a belt drier until the residual moisture content is preferably 0.5 to 15% by weight, more preferably 1 to 10% by weight, most preferably 2 to 8% by weight, the residual moisture content being determined by EDANA (European Disposables and Nonwovens Association) recommended test method No. WSP 230.2-05 “Moisture Content”.
- the dried polymer gel has too low a glass transition temperature T g and can be processed further only with difficulty.
- the dried polymer gel is too brittle and, in the subsequent comminution steps, undesirably large amounts of polymer particles with an excessively low particle size are obtained (fines).
- the solids content of the gel before the drying is preferably from 25 to 90% by weight, more preferably from 35 to 70% by weight, most preferably from 40 to 60% by weight.
- a fluidized bed drier or a paddle drier for the drying operation.
- the dried polymer gel is ground and classified, and the apparatus used for grinding may typically be single- or multistage roll mills, preferably two- or three-stage roll mills, pin mills, hammer mills or vibratory mills.
- the mean particle size of the polymer particles removed as the product fraction is preferably at least 200 ⁇ m, more preferably from 250 to 600 ⁇ m, very particularly from 300 to 500 ⁇ m.
- the mean particle size of the product fraction may be determined by means of EDANA (European Disposables and Nonwovens Association) recommended test method No. WSP 220.2-05 “Particle Size Distribution”, where the proportions by mass of the screen fractions are plotted in cumulated form and the mean particle size is determined graphically.
- the mean particle size here is the value of the mesh size which gives rise to a cumulative 50% by weight.
- the proportion of particles with a particle size of at least 150 ⁇ m is preferably at least 90% by weight, more preferably at least 95% by weight, most preferably at least 98% by weight.
- Polymer particles with too small a particle size lower the saline flow conductivity or gel bed permeability (SFC or GBP).
- SFC or GBP gel bed permeability
- Excessively small polymer particles are therefore typically removed and recycled into the process. This is preferably done before, during or immediately after the polymerization, i.e. before the drying of the polymer gel.
- the excessively small polymer particles can be moistened with water and/or aqueous surfactant before or during the recycling.
- the excessively small polymer particles are preferably added during the last third of the polymerization.
- the excessively small polymer particles When the excessively small polymer particles are added at a very late stage, for example not until in an apparatus connected downstream of the polymerization reactor, for example to an extruder, the excessively small polymer particles can be incorporated into the resulting polymer gel only with difficulty. Insufficiently incorporated, excessively small polymer particles are, however, detached again from the dried polymer gel during the grinding, are therefore removed again in the course of classification and increase the amount of excessively small polymer particles to be recycled.
- the proportion of particles having a particle size of at most 850 ⁇ m is preferably at least 90% by weight, more preferably at least 95% by weight, most preferably at least 98% by weight.
- the proportion of particles having a particle size of at most 600 ⁇ m is preferably at least 90% by weight, more preferably at least 95% by weight, most preferably at least 98% by weight.
- Polymer particles with too great a particle size lower the swell rate.
- the proportion of excessively large polymer particles should therefore likewise be small.
- the polymer particles can be surface postcrosslinked.
- Suitable surface postcrosslinkers are compounds which comprise groups which can form covalent bonds with at least two carboxylate groups of the polymer particles.
- Suitable compounds are, for example, polyfunctional amines, polyfunctional amido amines, polyfunctional epoxides, as described in EP 0 083 022 A2, EP 0 543 303 A1 and 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 DE 102 04 938 A1 and U.S. Pat. No. 6,239,230.
- suitable surface postcrosslinkers are cyclic carbonates in DE 40 20 780 C1, 2-oxazolidone and its derivatives, such as 2-hydroxyethyl-2-oxazolidone in DE 198 07 502 A1, bis- and poly-2-oxazolidinones in DE 198 07 992 01, 2-oxotetrahydro-1,3-oxazine and its derivatives in DE 198 54 573 A1, N-acyl-2-oxazolidones in DE 198 54 574 A1, cyclic ureas in DE 102 04 937 A1, bicyclic amide acetals in DE 103 34 584 A1, oxetanes and cyclic ureas in EP 1 199 327 A2 and morpholine-2,3-dione and its derivatives in WO 2003/031482 A1.
- 2-oxazolidone and its derivatives such as 2-hydroxyethyl-2-oxazolidone in DE 198 07 502 A1, bis- and poly-2
- 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-hydroxyethyloxazolidin-2-one, oxazolidin-2-one and 1,3-propanediol.
- the amount of surface postcrosslinkers is preferably 0.001 to 2% by weight, more preferably 0.02 to 1% by weight, most preferably 0.05 to 0.2% by weight, based in each case 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 usable 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.
- Possible counterions are chloride, bromide, sulfate, hydrogensulfate, carbonate, hydrogencarbonate, nitrate, phosphate, hydrogenphosphate, dihydrogenphosphate and carboxylate, such as acetate, tartate, citrate and lactate.
- Aluminum sulfate, basic aluminum acetate and aluminum lactate are preferred.
- polyamines it is also possible to use polyamines 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, more preferably 0.02 to 0.8% by weight, based in each case on the polymer particles.
- the surface postcrosslinking is typically performed in such a way that a solution of the surface postcrosslinker is sprayed onto the dried polymer particles. After the spraying, the polymer particles coated with surface postcrosslinker are dried thermally, and the surface postcrosslinking reaction can take place either before or during the drying.
- the spraying of a solution of the surface postcrosslinker is preferably performed 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 particular preference to vertical mixers.
- the distinction between horizontal mixers and vertical mixers is made by the position of the mixing shaft, i.e. horizontal mixers have a horizontally mounted mixing shaft and vertical mixers a vertically mounted mixing shaft.
- Suitable mixers are, for example, horizontal Pflugschar® plowshare mixers (Gebr.
- the surface postcrosslinkers are typically used in the form of an aqueous solution.
- the content of nonaqueous solvent and/or total amount of solvent can be used to adjust the penetration depth of the surface postcrosslinker into the polymer particles.
- a surfactant is advantageously added. This improves the wetting performance and reduces the tendency to form lumps.
- solvent mixtures for example isopropanol/water, 1,3-propanediol/water and propylene glycol/water, where the mixing ratio is preferably from 20:80 to 40:60.
- the thermal drying is preferably carried out in contact driers, more preferably paddle driers, most preferably disk driers.
- Suitable driers are, for example, Hosokawa Bepex® horizontal paddle driers (Hosokawa Micron GmbH; Leingart; Germany), Hosokawa Bepex® disk driers (Hosokawa Micron GmbH; Leingart; Germany) and Nara paddle driers (NARA Machinery Europe; Frechen; Germany).
- the drying can be effected in the mixer itself, by heating the jacket or blowing in warm air.
- a downstream drier for example a shelf drier, a rotary tube oven or a heatable screw. It is particularly advantageous to mix and dry in a fluidized bed drier.
- Preferred drying temperatures are in the range from 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 drier is preferably at least 10 minutes, more preferably at least 20 minutes, most preferably at least 30 minutes, and typically at most 60 minutes.
- the surface postcrosslinked polymer particles can be classified again, excessively small and/or excessively large polymer particles being removed and recycled into the process.
- the surface postcrosslinked polymer particles can be coated or remoisturized.
- the optional remoisturizing is carried out preferably at 30 to 80° C., more preferably at 35 to 70° C. and most preferably at 40 to 60° C. At excessively low temperatures, the water-absorbing polymer particles tend to form lumps, and, at higher temperatures, water already evaporates noticeably.
- the amount of water used for remoisturizing is preferably from 1 to 10% by weight, more preferably from 2 to 8% by weight and most preferably from 3 to 5% by weight. The remoisturizing increases the mechanical stability of the polymer particles and reduces their tendency to static charging.
- Suitable coatings for improving the swell rate and the saline flow conductivity or gel bed 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 coatings for counteracting the undesired 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 produced by the process according to the invention have a moisture content of preferably 0 to 15% by weight, more preferably 0.2 to 10% by weight, most preferably 0.5 to 8% by weight, the moisture content being determined by EDANA (European Disposables and Nonwovens Association) recommended test method No. WSP 230.2-05 “Moisture Content”.
- EDANA European Disposables and Nonwovens Association
- the water-absorbing polymer particles produced by the process according to the invention have a centrifuge retention capacity (CRC) of typically at least 15 g/g, preferably at least 20 g/g, preferentially 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 typically less than 60 g/g.
- the centrifuge retention capacity (CRC) is determined by EDANA (European Disposables and Nonwovens Association) recommended test method No. WSP 241.2-05 “Centrifuge Retention Capacity”.
- the water-absorbing polymer particles produced by the process according to the invention have an absorption under a pressure of 49.2 g/cm 2 of typically at least 15 g/g, preferably at least 20 g/g, preferentially at least 22 g/g, more preferably at least 24 g/g, most preferably at least 26 g/g.
- the absorption under a pressure of 49.2 g/cm 2 of the water-absorbing polymer particles is typically less than 35 g/g.
- the absorption under a pressure of 49.2 g/cm 2 is determined analogously to EDANA (European Disposables and Nonwovens Association) recommended test method No. WSP 242.2-05 “Absorption under Pressure”, except that a pressure of 49.2 g/cm 2 is established instead of a pressure of 21.0 g/cm 2 .
- the hygiene articles especially disposable diapers, consist of
- the upper liquid-pervious layer (A) is the layer which has direct contact with the skin.
- the material for this consists of customary synthetic or semisynthetic fibers, such as polyesters, polyolefins and rayon, or of customary natural fibers, such as cotton.
- the fibers should generally be bonded by binders such as polyacrylates.
- Preferred materials are polyester, rayon, polyethylene and polypropylene. Examples of liquid-pervious layers are described, for example, in WO 99/57355 A1 and EP 1 023 883 A2.
- the lower liquid-impervious layer (B) consists typically of a polyethylene or polypropylene film. However, it may also consist of any other film-forming polymer, for example of polyester, polyamide, especially biodegradable polyester.
- the inventive water-absorbing storage layers are essentially free of cellulose fibers or have a proportion of cellulose fibers of preferably less than 30% by weight, preferentially less than 20% by weight, more preferably less than 10% by weight, most preferably less than 5% by weight.
- the water-absorbing polymer particles usable are not subject to any restriction. Preference is given, however, to using water-absorbing polymer particles with a saline flow conductivity (SFC) of 50 to 150 ⁇ 10 ⁇ 7 cm 3 s/g, the saline flow conductivity (SFC) being determinable by the method described in WO 2008/092843 A1 (page 30, lines 16 to 36).
- SFC saline flow conductivity
- GBP gel bed permeability
- the absorption rate of the water-absorbing polymer particles for aqueous body fluids is adjusted optimally to the particular demands in the water-absorbing storage layer.
- the vortex times of the water-absorbing polymer particles should be less than 120 seconds, preferably less than 80 seconds, preferentially less than 50 seconds, more preferably less than 40 seconds, most preferably less than 20 seconds.
- the acquisition distribution layer (D) consists typically of cellulose fibers, modified cellulose or synthetic fibers, and has the task of rapidly absorbing aqueous liquids, for example urine, and passing them on to the water-absorbing layer (C).
- cellulose fibers For the acquisition distribution layer (D), preferably modified, more preferably chemically modified, most preferably chemically stiffened, cellulose fibers are used.
- Suitable agents for chemical stiffening are cationically modified starches, polyamide-epichlorohydrin resins, polyacrylamides, urea-formaldehyde resins, melamine-formaldehyde resins and polyethyleneimine resins.
- the stiffening can also be effected by modifying the chemical structure, for example by crosslinking.
- the crosslinkers can crosslink the polymer chains by formation of covalent bonds. Suitable crosslinkers are, for example, C 2 - to C 8 -dialdehydes, C 2 - to C 8 -monoaldehydes with a carboxylic acid group and C 2 - to C 8 -dicarboxylic acids.
- improved water-absorbing storage layers are obtained, as are hygiene articles which comprise them.
- the separation of liquid storage and liquid conduction can firstly significantly lower material consumption, especially of fibers, for production of the storage layers; secondly, thin and soft hygiene articles are obtained, which have outstanding integrity when dry and in use, since the water-absorbing polymer particles can be fixed significantly more efficiently.
Abstract
The present invention relates to improved water-absorbing storage layers for use in hygiene articles, the water-absorbing storage layers being essentially free of cellulose fibers.
Description
- The present invention relates to improved water-absorbing storage layers for use in hygiene articles, the water-absorbing storage layers being essentially free of cellulose fibers.
- The production of water-absorbing polymer particles and the use thereof for producing hygiene articles is described, for example, in the monograph “Modern Superabsorbent Polymer Technology”, F. L. Buchholz and A. T. Graham, Wiley-VCH, 1998, especially on pages 252 to 258. The water-absorbing polymer particles are also referred to as superabsorbents.
- The currently commercially available disposable diapers consist typically of a liquid-pervious topsheet (A), a liquid-impervious backsheet (B), a water-absorbing storage layer (C) between layers (A) and (B), and an acquisition distribution layer (D) between layers (A) and (C).
- The water-absorbing storage layer consists typically of a mixture of water-absorbing polymer particles and cellulose fibers, the water-absorbing polymer particles being fixed by the cellulose matrix.
- In the last few years, there has been a trend toward ever thinner disposable diapers. To produce ever thinner disposable diapers, the proportion of cellulose fibers in the water-absorbing storage layer has been lowered ever further. A disadvantage here is that the cellulose matrix is made ever thinner as a result, and the mobility of the water-absorbing polymer particles in the water-absorbing storage layer increases.
- Especially when water-absorbing storage layers essentially free of cellulose fibers are desired, i.e. consist virtually exclusively of water-absorbing polymer particles, there is the risk that the water-absorbing polymer particles will slip within the disposable diaper or even fall out of the disposable diaper completely.
- To solve this problem, novel water-absorbing storage layers have been produced. For example, WO 97/17397 A1 describes a process for producing water-absorbing foams. Use of such foams allows the use of cellulose fibers to be dispensed with entirely. Cellulose-free hygiene articles can also be secured to suitable nonwoven backsheets by fixing of water-absorbing polymer particles by means of thermoplastic polymers, especially of hotmelt adhesives, provided that these thermoplastic polymers are spun out to form fine fibers. Such products are described, for example, in US 2003/0181115, US 2004/0167486, US 2004/071363, US 2005/097025, US 2007/156108, US 2008/0125735, EP 1 917 940 A1, EP 1 913 912 A1, EP 1 913 913 A2, EP 1 913 914 A2, EP 1 911 425 A2, EP 1 911 426 A2, EP 1 447 067 A1, EP 1 813 237 A2, EP 1 813 236 A2, EP 1 808 152 A2, EP 1 447 066 A1. The production processes are disclosed in WO 2008/155722 A2, WO 2008/155702 A1, WO 2008/155711 A1, WO 2008/155710 A1, WO 2008/155701 A2, WO 2008/155699 A1. A disadvantage is the relatively complex production process, since the spinning of the adhesive fibers in the presence of water-absorbing polymer particles is difficult and prone to faults.
- In addition, extensible cellulose-free hygiene articles are known, and US 2006/0004336, US 2007/0135785, and US 2005/0137085 disclose production thereof by simultaneous fiber spinning of suitable thermoplastic polymers and incorporation of water-absorbing polymer particles. This process too is complex and prone to faults.
- It was an object of the present invention to provide improved water-absorbing storage layers for hygiene articles, especially disposable diapers. For the improved water-absorbing storage layers, it should be possible to use the customary water-absorbing polymer particles. Moreover, the improved water-absorbing storage layers should be essentially free of cellulose fibers, and the water-absorbing polymer particles in the water-absorbing storage layer should neither slip nor fall out either in the dry or moist state. In the context of this application, “free of cellulose fibers” means that the cellulose content in the inventive storage layer is preferably less than 30% by weight, preferentially less than 20% by weight, more preferably less than 10% by weight, most preferably less than 5% by weight. Ideally, no cellulose at all is present.
- The object is achieved by water-absorbing storage layers consisting of a nonwoven backsheet, water-absorbing polymer particles and a liquid-pervious topsheet, wherein the water-absorbing polymer particles are fixed on the nonwoven backsheet.
- In one embodiment of the present invention, the liquid-pervious topsheet is adhesive bonded to the nonwoven backsheet to form pockets. For this purpose, customary adhesives can be used. However, it is also possible that the liquid-pervious topsheet and/or nonwoven backsheet is entirely or partly composed of a thermoplastic polymer, and the liquid-pervious topsheet is adhesive bonded to the nonwoven backsheet by partial melting. Suitable nonwoven backsheets may consist of mixtures of thermoplastic fibers (for example polyolefins, polyesters, polyamides) and non-thermoplastic fibers (for example cellulose).
- The formation of pockets filled with water-absorbing polymer particles imparts the form of a quilt to the water-absorbing storage layer. The water-absorbing polymer particles are prevented from slipping within the water-absorbing storage layer by the pockets.
- In a further preferred variant of this embodiment, the depressions are partly filled with a liquid-conducting filler material and the pockets are optionally also additionally covered thereby. Useful filler materials for this purpose include hydrophilic fibers alone (for example cellulose, viscose or rayon) or in a mixture with other fibers (for example propylene or cellulose acetate). The fibers may also be those which consist of more than one component and which have a bi- or multilamellar or hollow cross section. Such fibers typically conduct the liquid better than simple smooth fibers.
- Advantageously, the depressions formed in the water-absorbing storage layer by virtue of the adhesive bonding of the liquid-pervious topsheet to the nonwoven backsheet are filled with further water-absorbing polymer particles and fixed to a further liquid-pervious topsheet.
-
FIGS. 1 a and 1 b show cross sections, andFIG. 1 c shows a longitudinal section, of the inventive water-absorbing storage layers of the first embodiment, the reference numerals having the following meanings: - 1 nonwoven backsheet
- 2 liquid-pervious topsheet
- 3 water-absorbing polymer particles
- 4 adhesive bond
- 5 second liquid-pervious topsheet
- 6 additional adhesive bond
- 7 machine running direction.
- In a second embodiment of the present invention, a nonwoven substrate with preferably hydrophilic fibers protruding upward is used. The water-absorbing polymer particles are fixed by the fibers between the nonwoven backsheet and the liquid-pervious topsheet. The liquid-pervious topsheet is preferably adhesive bonded to the fibers of the nonwoven backsheet. The fibers protruding upward may consist of all known polymers and mixtures thereof, but preference is given to polyolefins, polyesters, polyurethanes, cellulose and derivatives thereof, polyamides. The fibers may also be those which consist of more than one component and which have a bi- or multilamellar or hollow cross section.
-
FIG. 2 shows a cross section of the inventive water-absorbing storage layers of the second embodiment, the reference numerals having the following meanings: - 8 nonwoven backsheet
- 9 liquid-pervious topsheet
- 10 water-absorbing polymer particles
- 11 fibers directed upward.
- In a third embodiment of the present invention, a soft matrix composed of a liquid-pervious material is applied to the nonwoven backsheet, and the water-absorbing polymer particles are introduced into the chambers of the matrix. The chambers of the matrix are sealed with a liquid-pervious topsheet. The soft matrix is preferably adhesive bonded to the nonwoven backsheet and the liquid-pervious topsheet.
- An advantage of this embodiment is that the matrix material can be selected such that it additionally promotes liquid distribution within the water-absorbing storage layer. Suitable for this purpose are pressed hydrophilic fibers (for example of cellulose, chemically precipitated cellulose or crosslinked cellulose), or open-pore soft sponges. In the case of sponges, hydrophilic types are preferred. The matrix material should have, in the expanded state (unpressed), continuous pores with diameter preferably of 0.001 to 2.0 mm, preferably of 0.01 to 1.0 mm, more preferably of 0.03 to 0.5 mm, most preferably of 0.06 to 0.3 mm.
-
FIG. 3 a shows a top view, andFIG. 3 b shows cross sections, of the inventive water-absorbing storage layers of the third embodiment, the reference numerals having the following meanings: - 12 nonwoven backsheet
- 13 liquid-pervious topsheet
- 14 water-absorbing polymer particles
- 15 liquid-pervious matrix.
- In all embodiments, in a further particularly preferred variant, it is additionally possible to use a water-soluble adhesive for dry fixing of the water-absorbing polymer particles. The adhesive is applied, for example, to the nonwoven backsheet before the application of the water-absorbing polymer particles. The application can be effected, for example, in punctiform fashion, over the whole area, or preferably in strips in or transverse to or diagonally with respect to the machine running direction. The water-soluble adhesive may consist, for example, of polyvinyl alcohol, polyvinylpyrrolidone, polyethylene glycol, starch and starch derivatives, cellulose and cellulose derivatives, or polyacrylic acid. Most preferably, the water-soluble adhesive comprises at least one polyamine or consists thereof. Suitable polyamines are polyvinylamines, polyethyleneimines, polyallylamines. Particular preference is given to polyvinylamine. On contact with moisture, the amine is released from the adhesive and becomes attached to the swelling hydrogel, which additionally causes a particular gel layer stability in the swollen state.
- In preferred embodiments, a web of the nonwoven backsheet is moved in machine direction, and strips or geometric patterns comprising water-absorbing polymer particles are applied thereto. In the second embodiment of the present invention, a continuous surface may be obtained in this way. In all three embodiments, however, any desired geometric forms and patterns are conceivable, for example one which are arranged like cushions comprising water-absorbing polymer particles in terms of area. The cushions or the heaps of water-absorbing polymer particles applied may assume any desired shape in terms of area, for example circles, ellipses, rectangles, squares, triangles (viewed from above). Particular preference is given to any desired polygons or mixtures of polygons with which the two-dimensional surface can be covered without gaps. Particular preference is also given to the application of one or more continuous strips in machine running direction, the strips running parallel to one another.
- In the case of pockets, it is advantageous to fill them loosely, in order that the water-absorbing polymer particles can swell in a substantially unhindered manner. Optionally, however, an elastic nonwoven can also be used as a topsheet or as a backsheet. Such nonwovens are commercially available.
- In all embodiments, the nonwoven backsheet is fixed on a suitable machine by means of reduced pressure such that water-absorbing polymer particles to be laid on can then be laid on there by means of masks or similar means, such that these water-absorbing polymer particles are held fixed from below by the existing suction during processing. It is thus equally possible to temporarily fix the other components.
- A. Water-Absorbing Polymer Particles
- The water-absorbing polymer particles are produced by polymerizing a monomer solution or suspension and are typically water-insoluble.
- The monomers a) are preferably water-soluble, i.e. 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.
- Further suitable monomers a) are, for example, ethylenically unsaturated sulfonic acids, such as styrenesulfonic acid and 2-acrylamido-2-methylpropanesulfonic acid (AMPS).
- Impurities can have a considerable influence on the polymerization. The raw materials used should therefore have a maximum purity. It is therefore often advantageous to specially purify the monomers a). Suitable purification processes are described, for example, in WO 2002/055469 A1, WO 2003/078378 A1 and WO 2004/035514 A1. A suitable monomer a) is, for example, acrylic acid purified according to WO 2004/035514 A1 comprising 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 furfurals, 0.0001% by weight of maleic anhydride, 0.0003% by weight of diacrylic acid and 0.0050% by weight of hydroquinone monomethyl ether.
- The proportion of acrylic acid and/or salts thereof in the total amount of monomers a) is preferably at least 50 mol %, more preferably at least 90 mol %, most preferably at least 95 mol %.
- The monomers a) typically comprise polymerization inhibitors, preferably hydroquinone monoethers, as storage stabilizers.
- The monomer solution comprises preferably up to 250 ppm by weight, preferably at most 130 ppm by weight, more preferably at most 70 ppm by weight, preferably at least 10 ppm by weight, more preferably at least 30 ppm by weight, especially around 50 ppm by weight, of hydroquinone monoether, based in each case on the unneutralized monomer a). For example, the monomer solution can be prepared by using an ethylenically unsaturated monomer bearing acid groups with an appropriate content of hydroquinone monoether.
- Preferred hydroquinone monoethers 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 polymerized free-radically into the polymer chain, and functional groups which can form covalent bonds with the acid groups of the monomer a). In addition, polyvalent metal salts which can form coordinate bonds with at least two acid groups of the monomer a) are also suitable as crosslinkers b).
- Crosslinkers b) are preferably compounds having at least two polymerizable groups which can be polymerized free-radically into the polymer network. 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 described in EP 0 547 847 A1, EP 0 559 476 A1, EP 0 632 068 A1, WO 93/21237 A1, WO 2003/104299 A1, WO 2003/104300 A1, WO 2003/104301 A1 and DE 103 31 450 A1, mixed acrylates which, as well as acrylate groups, comprise further ethylenically unsaturated groups, as described in DE 103 31 456 A1 and DE 103 55 401 A1, or crosslinker mixtures, as described, for example, in DE 195 43 368 A1, DE 196 46 484 A1, WO 90/15830 A1 and WO 2002/032962 A2.
- Preferred crosslinkers b) are pentaerythrityl triallyl ether, tetraalloxyethane, methylenebismethacrylamide, 15-tuply ethoxylated trimethylolpropane triacrylate, polyethylene glycol diacrylate, trimethylolpropane triacrylate and triallylamine.
- Very particularly preferred crosslinkers b) are the polyethoxylated and/or -propoxylated glycerols which have been esterified with acrylic acid or methacrylic acid to give di- or triacrylates, as described, for example, in WO 2003/104301 A1. Di- and/or triacrylates of 3- to 10-tuply ethoxylated glycerol are particularly advantageous. Very particular preference is given to di- or triacrylates of 1- to 5-tuply ethoxylated and/or propoxylated glycerol. Most preferred are the triacrylates of 3- to 5-tuply ethoxylated and/or propoxylated glycerol, especially the triacrylate of 3-tuply ethoxylated glycerol.
- The amount of crosslinker b) is preferably 0.05 to 1.5% by weight, more preferably 0.1 to 1% by weight, most preferably 0.3 to 0.6% by weight, based in each case on monomer a). With rising crosslinker content, the centrifuge retention capacity (CRC) falls and the absorption under a pressure of 21.0 g/cm2 passes through a maximum.
- The initiators c) used may be 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. Preference is given to using mixtures of thermal initiators and redox initiators, such as sodium peroxodisulfate/hydrogen peroxide/ascorbic acid. The reducing component used is, however, 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 obtainable as Bruggolite® FF6 and Bruggolite® FF7 (Bruggemann Chemicals; Heilbronn; Germany).
- Ethylenically unsaturated monomers d) copolymerizable with the ethylenically unsaturated monomers a) bearing acid groups are, for example, acrylamide, methacrylamide, hydroxyethyl acrylate, hydroxyethyl methacrylate, dimethylaminoethyl methacrylate, dimethylaminoethyl acrylate, dimethylaminopropyl acrylate, diethylaminopropyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate.
- The water-soluble polymers e) used may be 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.
- Typically, an aqueous monomer solution is used. The water content of the monomer solution is preferably from 40 to 75% by weight, more preferably from 45 to 70% by weight, most preferably from 50 to 65% by weight. It is also possible to use monomer suspensions, i.e. monomer solutions with excess monomer a), for example sodium acrylate. With rising water content, the energy requirement in the subsequent drying rises, and, with falling water content, the heat of polymerization can only be removed inadequately.
- For optimal action, the preferred polymerization inhibitors require dissolved oxygen. The monomer solution can therefore be freed of dissolved oxygen before the polymerization by inertization, i.e. flowing an inert gas through, preferably nitrogen or carbon dioxide. The oxygen content of the monomer solution is preferably lowered before the polymerization to less than 1 ppm by weight, more preferably to less than 0.5 ppm by weight, most preferably to less than 0.1 ppm by weight.
- Suitable reactors are, for example, kneading reactors or belt reactors. In the kneader, the polymer gel formed in the polymerization of an aqueous monomer solution or suspension is comminuted continuously by, for example, contrarotatory stirrer shafts, as described in WO 2001/038402 A1. Polymerization on a belt is described, for example, in DE 38 25 366 A1 and U.S. Pat. No. 6,241,928. Polymerization in a belt reactor forms a polymer gel, which has to be comminuted in a further process step, for example in an extruder or kneader.
- To improve the drying properties, the comminuted polymer gel obtained by means of a kneader can additionally be extruded.
- However, it is also possible to dropletize an aqueous monomer solution and to polymerize the droplets obtained in a heated carrier gas stream. This allows the process steps of polymerization and drying to be combined, as described in WO 2008/040715 A2 and WO 2008/052971 A1.
- The acid groups of the resulting polymer gels have typically been partially neutralized. Neutralization is preferably carried out at the monomer stage. This is typically done by mixing in the neutralizing agent as an aqueous solution or preferably also as a solid. The degree of neutralization is preferably from 25 to 95 mol %, more preferably from 30 to 80 mol %, most preferably from 40 to 75 mol %, for which the customary neutralizing agents can be used, preferably alkali metal hydroxides, alkali metal oxides, alkali metal carbonates or alkali metal hydrogencarbonates and also mixtures thereof. Instead of alkali metal salts, it is also possible to use ammonium salts. Particularly preferred alkali metals are sodium and potassium, but very particular preference is given to sodium hydroxide, sodium carbonate or sodium hydrogencarbonate and also mixtures thereof.
- However, it is also possible to carry out neutralization after the polymerization, at the stage of the polymer gel formed in the polymerization. It is also possible to neutralize up to 40 mol %, preferably 10 to 30 mol % and more preferably 15 to 25 mol % of the acid groups before the polymerization by adding a portion of the neutralizing agent actually to the monomer solution and setting the desired final degree of neutralization only after the polymerization, at the polymer gel stage. When the polymer gel is neutralized at least partly after the polymerization, the polymer gel is preferably comminuted mechanically, for example by means of an extruder, in which case the neutralizing agent can be sprayed, sprinkled or poured on and then carefully mixed in. To this end, the gel mass obtained can be repeatedly extruded for homogenization.
- The polymer gel is then preferably dried with a belt drier until the residual moisture content is preferably 0.5 to 15% by weight, more preferably 1 to 10% by weight, most preferably 2 to 8% by weight, the residual moisture content being determined by EDANA (European Disposables and Nonwovens Association) recommended test method No. WSP 230.2-05 “Moisture Content”. In the case of too high a residual moisture content, the dried polymer gel has too low a glass transition temperature Tg and can be processed further only with difficulty. In the case of too low a residual moisture content, the dried polymer gel is too brittle and, in the subsequent comminution steps, undesirably large amounts of polymer particles with an excessively low particle size are obtained (fines). The solids content of the gel before the drying is preferably from 25 to 90% by weight, more preferably from 35 to 70% by weight, most preferably from 40 to 60% by weight. Optionally, it is, however, also possible to use a fluidized bed drier or a paddle drier for the drying operation.
- Thereafter, the dried polymer gel is ground and classified, and the apparatus used for grinding may typically be single- or multistage roll mills, preferably two- or three-stage roll mills, pin mills, hammer mills or vibratory mills.
- The mean particle size of the polymer particles removed as the product fraction is preferably at least 200 μm, more preferably from 250 to 600 μm, very particularly from 300 to 500 μm. The mean particle size of the product fraction may be determined by means of EDANA (European Disposables and Nonwovens Association) recommended test method No. WSP 220.2-05 “Particle Size Distribution”, where the proportions by mass of the screen fractions are plotted in cumulated form and the mean particle size is determined graphically. The mean particle size here is the value of the mesh size which gives rise to a cumulative 50% by weight.
- The proportion of particles with a particle size of at least 150 μm is preferably at least 90% by weight, more preferably at least 95% by weight, most preferably at least 98% by weight.
- Polymer particles with too small a particle size lower the saline flow conductivity or gel bed permeability (SFC or GBP). The proportion of excessively small polymer particles (fines) should therefore be small.
- Excessively small polymer particles are therefore typically removed and recycled into the process. This is preferably done before, during or immediately after the polymerization, i.e. before the drying of the polymer gel. The excessively small polymer particles can be moistened with water and/or aqueous surfactant before or during the recycling.
- It is also possible in later process steps to remove excessively small polymer particles, for example after the surface postcrosslinking or another coating step. In this case, the excessively small polymer particles recycled are surface postcrosslinked or coated in another way, for example with fumed silica.
- When a kneading reactor is used for polymerization, the excessively small polymer particles are preferably added during the last third of the polymerization.
- When the excessively small polymer particles are added at a very early stage, for example actually to the monomer solution, this lowers the centrifuge retention capacity (CRC) of the resulting water-absorbing polymer particles. However, this can be compensated, for example, by adjusting the amount of crosslinker b) used.
- When the excessively small polymer particles are added at a very late stage, for example not until in an apparatus connected downstream of the polymerization reactor, for example to an extruder, the excessively small polymer particles can be incorporated into the resulting polymer gel only with difficulty. Insufficiently incorporated, excessively small polymer particles are, however, detached again from the dried polymer gel during the grinding, are therefore removed again in the course of classification and increase the amount of excessively small polymer particles to be recycled.
- The proportion of particles having a particle size of at most 850 μm is preferably at least 90% by weight, more preferably at least 95% by weight, most preferably at least 98% by weight.
- The proportion of particles having a particle size of at most 600 μm is preferably at least 90% by weight, more preferably at least 95% by weight, most preferably at least 98% by weight.
- Polymer particles with too great a particle size lower the swell rate. The proportion of excessively large polymer particles should therefore likewise be small.
- Excessively large polymer particles are therefore typically removed and recycled into the grinding of the dried polymer gel.
- To further improve the properties, the polymer particles can be surface postcrosslinked. Suitable surface postcrosslinkers are compounds which comprise groups which can form covalent bonds with at least two carboxylate groups of the polymer particles. Suitable compounds are, for example, polyfunctional amines, polyfunctional amido amines, polyfunctional epoxides, as described in EP 0 083 022 A2, EP 0 543 303 A1 and 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 β-hydroxyalkylamides, as described in DE 102 04 938 A1 and U.S. Pat. No. 6,239,230.
- Additionally described as suitable surface postcrosslinkers are cyclic carbonates in DE 40 20 780 C1, 2-oxazolidone and its derivatives, such as 2-hydroxyethyl-2-oxazolidone in DE 198 07 502 A1, bis- and poly-2-oxazolidinones in DE 198 07 992 01, 2-oxotetrahydro-1,3-oxazine and its derivatives in DE 198 54 573 A1, N-acyl-2-oxazolidones in DE 198 54 574 A1, cyclic ureas in DE 102 04 937 A1, bicyclic amide acetals in DE 103 34 584 A1, oxetanes and cyclic ureas in EP 1 199 327 A2 and morpholine-2,3-dione and its derivatives in WO 2003/031482 A1.
- 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-hydroxyethyloxazolidin-2-one, oxazolidin-2-one and 1,3-propanediol.
- In addition, it is also possible to use surface postcrosslinkers which comprise additional polymerizable ethylenically unsaturated groups, as described in DE 37 13 601 A1.
- The amount of surface postcrosslinkers is preferably 0.001 to 2% by weight, more preferably 0.02 to 1% by weight, most preferably 0.05 to 0.2% by weight, based in each case on the polymer particles.
- In a preferred embodiment of the present invention, polyvalent cations are applied to the particle surface in addition to the surface postcrosslinkers before, during or after the surface postcrosslinking.
- The polyvalent cations usable 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. Possible counterions are chloride, bromide, sulfate, hydrogensulfate, carbonate, hydrogencarbonate, nitrate, phosphate, hydrogenphosphate, dihydrogenphosphate and carboxylate, such as acetate, tartate, citrate and lactate. Aluminum sulfate, basic aluminum acetate and aluminum lactate are preferred. Apart from metal salts, it is also possible to use polyamines 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, more preferably 0.02 to 0.8% by weight, based in each case on the polymer particles.
- The surface postcrosslinking is typically performed in such a way that a solution of the surface postcrosslinker is sprayed onto the dried polymer particles. After the spraying, the polymer particles coated with surface postcrosslinker are dried thermally, and the surface postcrosslinking reaction can take place either before or during the drying.
- The spraying of a solution of the surface postcrosslinker is preferably performed in mixers with moving mixing tools, such as screw mixers, disk mixers and paddle mixers. Particular preference is given to horizontal mixers such as paddle mixers, very particular preference to vertical mixers. The distinction between horizontal mixers and vertical mixers is made by the position of the mixing shaft, i.e. horizontal mixers have a horizontally mounted mixing shaft and vertical mixers a vertically mounted mixing shaft. Suitable mixers are, for example, horizontal Pflugschar® plowshare mixers (Gebr. Lödige Maschinenbau GmbH; Paderborn; Germany), Vrieco-Nauta continuous mixers (Hosokawa Micron BV; Doetinchem; the Netherlands), Processall Mixmill mixers (Processall Incorporated; Cincinnati; US) and Schugi Flexomix® (Hosokawa Micron BV; Doetinchem; the Netherlands). However, it is also possible to spray on the surface postcrosslinker solution in a fluidized bed.
- The surface postcrosslinkers are typically used in the form of an aqueous solution. The content of nonaqueous solvent and/or total amount of solvent can be used to adjust the penetration depth of the surface postcrosslinker into the polymer particles.
- When exclusively water is used as the solvent, a surfactant is advantageously added. This improves the wetting performance and reduces the tendency to form lumps. However, preference is given to using solvent mixtures, for example isopropanol/water, 1,3-propanediol/water and propylene glycol/water, where the mixing ratio is preferably from 20:80 to 40:60.
- The thermal drying is preferably carried out in contact driers, more preferably paddle driers, most preferably disk driers. Suitable driers are, for example, Hosokawa Bepex® horizontal paddle driers (Hosokawa Micron GmbH; Leingarten; Germany), Hosokawa Bepex® disk driers (Hosokawa Micron GmbH; Leingarten; Germany) and Nara paddle driers (NARA Machinery Europe; Frechen; Germany). Moreover, it is also possible to use fluidized bed driers.
- The drying can be effected in the mixer itself, by heating the jacket or blowing in warm air. Equally suitable is a downstream drier, for example a shelf drier, a rotary tube oven or a heatable screw. It is particularly advantageous to mix and dry in a fluidized bed drier. Preferred drying temperatures are in the range from 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 drier is preferably at least 10 minutes, more preferably at least 20 minutes, most preferably at least 30 minutes, and typically at most 60 minutes.
- Subsequently, the surface postcrosslinked polymer particles can be classified again, excessively small and/or excessively large polymer particles being removed and recycled into the process.
- To further improve the properties, the surface postcrosslinked polymer particles can be coated or remoisturized.
- The optional remoisturizing is carried out preferably at 30 to 80° C., more preferably at 35 to 70° C. and most preferably at 40 to 60° C. At excessively low temperatures, the water-absorbing polymer particles tend to form lumps, and, at higher temperatures, water already evaporates noticeably. The amount of water used for remoisturizing is preferably from 1 to 10% by weight, more preferably from 2 to 8% by weight and most preferably from 3 to 5% by weight. The remoisturizing increases the mechanical stability of the polymer particles and reduces their tendency to static charging.
- Suitable coatings for improving the swell rate and the saline flow conductivity or gel bed permeability (SFC or GBP) 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 coatings for counteracting the undesired 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 produced by the process according to the invention have a moisture content of preferably 0 to 15% by weight, more preferably 0.2 to 10% by weight, most preferably 0.5 to 8% by weight, the moisture content being determined by EDANA (European Disposables and Nonwovens Association) recommended test method No. WSP 230.2-05 “Moisture Content”.
- The water-absorbing polymer particles produced by the process according to the invention have a centrifuge retention capacity (CRC) of typically at least 15 g/g, preferably at least 20 g/g, preferentially 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 typically less than 60 g/g. The centrifuge retention capacity (CRC) is determined by EDANA (European Disposables and Nonwovens Association) recommended test method No. WSP 241.2-05 “Centrifuge Retention Capacity”.
- The water-absorbing polymer particles produced by the process according to the invention have an absorption under a pressure of 49.2 g/cm2 of typically at least 15 g/g, preferably at least 20 g/g, preferentially at least 22 g/g, more preferably at least 24 g/g, most preferably at least 26 g/g. The absorption under a pressure of 49.2 g/cm2 of the water-absorbing polymer particles is typically less than 35 g/g. The absorption under a pressure of 49.2 g/cm2 is determined analogously to EDANA (European Disposables and Nonwovens Association) recommended test method No. WSP 242.2-05 “Absorption under Pressure”, except that a pressure of 49.2 g/cm2 is established instead of a pressure of 21.0 g/cm2.
- B. Hygiene Articles
- The hygiene articles, especially disposable diapers, consist of
-
- (A) an upper liquid-pervious layer,
- (B) a lower liquid-impervious layer,
- (C) a water-absorbing storage layer (core) between layer (A) and layer (B), and
- (D) optionally an acquisition distribution layer between layer (A) and layer (C).
- The upper liquid-pervious layer (A) is the layer which has direct contact with the skin.
- The material for this consists of customary synthetic or semisynthetic fibers, such as polyesters, polyolefins and rayon, or of customary natural fibers, such as cotton. In the case of nonwoven materials, the fibers should generally be bonded by binders such as polyacrylates. Preferred materials are polyester, rayon, polyethylene and polypropylene. Examples of liquid-pervious layers are described, for example, in WO 99/57355 A1 and EP 1 023 883 A2.
- The lower liquid-impervious layer (B) consists typically of a polyethylene or polypropylene film. However, it may also consist of any other film-forming polymer, for example of polyester, polyamide, especially biodegradable polyester.
- The inventive water-absorbing storage layers are essentially free of cellulose fibers or have a proportion of cellulose fibers of preferably less than 30% by weight, preferentially less than 20% by weight, more preferably less than 10% by weight, most preferably less than 5% by weight. The water-absorbing polymer particles usable are not subject to any restriction. Preference is given, however, to using water-absorbing polymer particles with a saline flow conductivity (SFC) of 50 to 150×10−7 cm3 s/g, the saline flow conductivity (SFC) being determinable by the method described in WO 2008/092843 A1 (page 30, lines 16 to 36).
- It is likewise possible to use water-absorbing polymer particles with a gel bed permeability (GBP) of 10 to 100 darcies. In a particular embodiment, water-absorbing polymer particles with a gel bed permeability (GBP) of 100 to 1000 darcies are used. The gel bed permeability (GBP) is determined to US 2005/0256757.
- It is additionally advantageous to use water-absorbing polymer particles with a centrifuged retention capacity (CRC) of at least 33 g/g and an absorption under pressure of 49.2 g/cm2(AUL0.7 psi) of at least 12 g/g.
- It is additionally advantageous when the absorption rate of the water-absorbing polymer particles for aqueous body fluids is adjusted optimally to the particular demands in the water-absorbing storage layer. To determine the absorption rate, preference is given to using the vortex test described in the literature, for example in the monograph “Modern Superabsorbent Polymer Technology”. F. L. Buchholz and A. T. Graham, Wiley-VCH, 1998, on pages 156 and 157. The vortex times of the water-absorbing polymer particles should be less than 120 seconds, preferably less than 80 seconds, preferentially less than 50 seconds, more preferably less than 40 seconds, most preferably less than 20 seconds.
- The acquisition distribution layer (D) consists typically of cellulose fibers, modified cellulose or synthetic fibers, and has the task of rapidly absorbing aqueous liquids, for example urine, and passing them on to the water-absorbing layer (C).
- For the acquisition distribution layer (D), preferably modified, more preferably chemically modified, most preferably chemically stiffened, cellulose fibers are used. Suitable agents for chemical stiffening are cationically modified starches, polyamide-epichlorohydrin resins, polyacrylamides, urea-formaldehyde resins, melamine-formaldehyde resins and polyethyleneimine resins.
- The stiffening can also be effected by modifying the chemical structure, for example by crosslinking. The crosslinkers can crosslink the polymer chains by formation of covalent bonds. Suitable crosslinkers are, for example, C2- to C8-dialdehydes, C2- to C8-monoaldehydes with a carboxylic acid group and C2- to C8-dicarboxylic acids.
- According to the present invention, improved water-absorbing storage layers are obtained, as are hygiene articles which comprise them. The separation of liquid storage and liquid conduction can firstly significantly lower material consumption, especially of fibers, for production of the storage layers; secondly, thin and soft hygiene articles are obtained, which have outstanding integrity when dry and in use, since the water-absorbing polymer particles can be fixed significantly more efficiently.
Claims (9)
1. A water-absorbing storage layer consisting of a nonwoven backsheet, water-absorbing polymer particles, and a liquid-pervious topsheet, wherein the water-absorbing polymer particles are fixed on the nonwoven backsheet.
2. The storage layer according to claim 1 , wherein the liquid-pervious topsheet has been adhesive bonded to the nonwoven backsheet to form pockets.
3. The storage layer according to claim 2 , wherein bridges between the pockets are filled with further water-absorbing polymer particles and said further water-absorbing polymer particles are fixed to a second liquid-pervious topsheet by adhesive bonding to the first liquid-pervious topsheet.
4. The storage layer according to claim 1 , wherein the nonwoven backsheet has fibers directed downward and the water-absorbing polymer particles are present in the region of the fibers.
5. The storage layer according to claim 4 , wherein the liquid-pervious topsheet has been adhesive bonded to the fibers.
6. The storage layer according to claim 1 , wherein a liquid-pervious matrix is present between the nonwoven backsheet and the liquid-pervious topsheet.
7. The storage layer according to claim 6 , wherein the liquid-pervious matrix has been adhesive bonded to the nonwoven backsheet and the liquid-pervious topsheet.
8. The storage layer according to claim 1 , wherein the water-absorbing polymer particles have a centrifuge retention capacity of at least 15 g/g.
9. A hygiene article comprising a water-absorbing storage layer according to claim 1 .
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP09160762.2 | 2009-05-20 | ||
EP09160762 | 2009-05-20 | ||
PCT/EP2010/056688 WO2010133529A2 (en) | 2009-05-20 | 2010-05-17 | Water-absorbent storage layers |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/EP2010/056688 A-371-Of-International WO2010133529A2 (en) | 2009-05-20 | 2010-05-17 | Water-absorbent storage layers |
Related Child Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US14/753,511 Continuation US9585798B2 (en) | 2009-05-20 | 2015-06-29 | Water absorbent storage layers |
Publications (1)
Publication Number | Publication Date |
---|---|
US20120064792A1 true US20120064792A1 (en) | 2012-03-15 |
Family
ID=42246082
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/319,591 Abandoned US20120064792A1 (en) | 2009-05-20 | 2010-05-17 | Water Absorbent Storage Layers |
US14/753,511 Active US9585798B2 (en) | 2009-05-20 | 2015-06-29 | Water absorbent storage layers |
Family Applications After (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US14/753,511 Active US9585798B2 (en) | 2009-05-20 | 2015-06-29 | Water absorbent storage layers |
Country Status (5)
Country | Link |
---|---|
US (2) | US20120064792A1 (en) |
EP (2) | EP2432511B1 (en) |
JP (1) | JP2012527267A (en) |
CN (1) | CN102438665B (en) |
WO (1) | WO2010133529A2 (en) |
Cited By (43)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8979815B2 (en) | 2012-12-10 | 2015-03-17 | The Procter & Gamble Company | Absorbent articles with channels |
US20150080822A1 (en) * | 2011-06-17 | 2015-03-19 | The Procter & Gamble Company | Absorbent article having improved absorption properties |
US9060904B2 (en) | 2007-06-18 | 2015-06-23 | The Procter & Gamble Company | Disposable absorbent article with sealed absorbent core with substantially continuously distributed absorbent particulate polymer material |
US9066838B2 (en) | 2011-06-10 | 2015-06-30 | The Procter & Gamble Company | Disposable diaper having reduced absorbent core to backsheet gluing |
US9072634B2 (en) | 2007-06-18 | 2015-07-07 | The Procter & Gamble Company | Disposable absorbent article with substantially continuously distributed absorbent particulate polymer material and method |
JP2015521678A (en) * | 2012-07-03 | 2015-07-30 | ビーエーエスエフ ソシエタス・ヨーロピアBasf Se | Process for producing water-absorbing polymer particles with improved properties |
US9216118B2 (en) | 2012-12-10 | 2015-12-22 | The Procter & Gamble Company | Absorbent articles with channels and/or pockets |
US9216116B2 (en) | 2012-12-10 | 2015-12-22 | The Procter & Gamble Company | Absorbent articles with channels |
US9326896B2 (en) | 2008-04-29 | 2016-05-03 | The Procter & Gamble Company | Process for making an absorbent core with strain resistant core cover |
US9340363B2 (en) | 2009-12-02 | 2016-05-17 | The Procter & Gamble Company | Apparatus and method for transferring particulate material |
US9375358B2 (en) | 2012-12-10 | 2016-06-28 | The Procter & Gamble Company | Absorbent article with high absorbent material content |
US9468566B2 (en) | 2011-06-10 | 2016-10-18 | The Procter & Gamble Company | Absorbent structure for absorbent articles |
US9492328B2 (en) | 2011-06-10 | 2016-11-15 | The Procter & Gamble Company | Method and apparatus for making absorbent structures with absorbent material |
US9532910B2 (en) | 2012-11-13 | 2017-01-03 | The Procter & Gamble Company | Absorbent articles with channels and signals |
US9585798B2 (en) | 2009-05-20 | 2017-03-07 | Basf Se | Water absorbent storage layers |
US9668926B2 (en) | 2011-06-10 | 2017-06-06 | The Procter & Gamble Company | Method and apparatus for making absorbent structures with absorbent material |
US9713557B2 (en) | 2012-12-10 | 2017-07-25 | The Procter & Gamble Company | Absorbent article with high absorbent material content |
US9713556B2 (en) | 2012-12-10 | 2017-07-25 | The Procter & Gamble Company | Absorbent core with high superabsorbent material content |
US9763835B2 (en) | 2003-02-12 | 2017-09-19 | The Procter & Gamble Company | Comfortable diaper |
US9789009B2 (en) | 2013-12-19 | 2017-10-17 | The Procter & Gamble Company | Absorbent articles having channel-forming areas and wetness indicator |
US9789011B2 (en) | 2013-08-27 | 2017-10-17 | The Procter & Gamble Company | Absorbent articles with channels |
US9974699B2 (en) | 2011-06-10 | 2018-05-22 | The Procter & Gamble Company | Absorbent core for disposable absorbent articles |
US9987176B2 (en) | 2013-08-27 | 2018-06-05 | The Procter & Gamble Company | Absorbent articles with channels |
US10052242B2 (en) | 2014-05-27 | 2018-08-21 | The Procter & Gamble Company | Absorbent core with absorbent material pattern |
US10071002B2 (en) | 2013-06-14 | 2018-09-11 | The Procter & Gamble Company | Absorbent article and absorbent core forming channels when wet |
US10130527B2 (en) | 2013-09-19 | 2018-11-20 | The Procter & Gamble Company | Absorbent cores having material free areas |
US10149788B2 (en) | 2011-06-10 | 2018-12-11 | The Procter & Gamble Company | Disposable diapers |
US10292875B2 (en) | 2013-09-16 | 2019-05-21 | The Procter & Gamble Company | Absorbent articles with channels and signals |
US10322040B2 (en) | 2015-03-16 | 2019-06-18 | The Procter & Gamble Company | Absorbent articles with improved cores |
US10441481B2 (en) | 2014-05-27 | 2019-10-15 | The Proctre & Gamble Company | Absorbent core with absorbent material pattern |
US10470948B2 (en) | 2003-02-12 | 2019-11-12 | The Procter & Gamble Company | Thin and dry diaper |
US10507144B2 (en) | 2015-03-16 | 2019-12-17 | The Procter & Gamble Company | Absorbent articles with improved strength |
US10543129B2 (en) | 2015-05-29 | 2020-01-28 | The Procter & Gamble Company | Absorbent articles having channels and wetness indicator |
US10561546B2 (en) | 2011-06-10 | 2020-02-18 | The Procter & Gamble Company | Absorbent structure for absorbent articles |
US10632029B2 (en) | 2015-11-16 | 2020-04-28 | The Procter & Gamble Company | Absorbent cores having material free areas |
US10639215B2 (en) | 2012-12-10 | 2020-05-05 | The Procter & Gamble Company | Absorbent articles with channels and/or pockets |
US10736795B2 (en) | 2015-05-12 | 2020-08-11 | The Procter & Gamble Company | Absorbent article with improved core-to-backsheet adhesive |
US10842690B2 (en) | 2016-04-29 | 2020-11-24 | The Procter & Gamble Company | Absorbent core with profiled distribution of absorbent material |
US11090199B2 (en) | 2014-02-11 | 2021-08-17 | The Procter & Gamble Company | Method and apparatus for making an absorbent structure comprising channels |
US11123240B2 (en) | 2016-04-29 | 2021-09-21 | The Procter & Gamble Company | Absorbent core with transversal folding lines |
US11207220B2 (en) | 2013-09-16 | 2021-12-28 | The Procter & Gamble Company | Absorbent articles with channels and signals |
AU2016430853B2 (en) * | 2016-11-30 | 2022-09-29 | Kimberly-Clark Worldwide, Inc. | Three-dimensional functional structure |
US11957551B2 (en) | 2021-11-16 | 2024-04-16 | The Procter & Gamble Company | Absorbent articles with channels and signals |
Families Citing this family (22)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP6129191B2 (en) | 2011-10-18 | 2017-05-17 | ビーエーエスエフ ソシエタス・ヨーロピアBasf Se | Fluid absorbent article |
CN104053421B (en) | 2011-10-24 | 2016-10-26 | 波士胶公司 | For the method preparing absorbing products |
EP2586409A1 (en) | 2011-10-24 | 2013-05-01 | Bostik SA | New absorbent article and process for making it |
EP2586412A1 (en) | 2011-10-24 | 2013-05-01 | Bostik SA | New absorbent article and process for making it |
EP2586410A1 (en) | 2011-10-24 | 2013-05-01 | Bostik SA | Novel process for preparing an absorbent article |
EP2609898A1 (en) | 2011-12-29 | 2013-07-03 | Bostik SA | Novel process for preparing an absorbent article |
WO2014079694A1 (en) | 2012-11-21 | 2014-05-30 | Basf Se | A process for producing surface-postcrosslinked water-absorbent polymer particles |
ES2637851T3 (en) * | 2012-12-21 | 2017-10-17 | Bostik, Inc. | Fluid absorbent article |
CN105683226B (en) | 2013-08-26 | 2018-08-17 | 巴斯夫欧洲公司 | Fluid-absorbent articles |
JP6590800B2 (en) * | 2013-10-30 | 2019-10-16 | ビーエーエスエフ ソシエタス・ヨーロピアBasf Se | Method for producing absorbent polymer particles by suspension polymerization |
US10881555B2 (en) | 2016-03-30 | 2021-01-05 | Basf Se | Fluid-absorbent article |
US10806640B2 (en) | 2016-03-30 | 2020-10-20 | Basf Se | Ultrathin fluid-absorbent article |
US20170281425A1 (en) | 2016-03-30 | 2017-10-05 | Basf Se | Fluid-absorbent article |
US10966884B2 (en) | 2016-07-05 | 2021-04-06 | The Procter & Gamble Company | Absorbent core having funnel-shaped swelling chamber |
EP3481351A1 (en) * | 2016-07-05 | 2019-05-15 | The Procter and Gamble Company | Absorbent core exhibiting material movement |
ES2932273T3 (en) | 2017-02-06 | 2023-01-17 | Basf Se | fluid absorbent article |
CN110312497B (en) | 2017-02-17 | 2021-12-10 | 巴斯夫欧洲公司 | Fluid-absorbent article |
JP6990108B2 (en) * | 2017-12-29 | 2022-01-12 | 花王株式会社 | Absorbent article |
AU2018411085A1 (en) * | 2018-02-28 | 2020-09-17 | Kimberly-Clark Worldwide, Inc. | Multi-layer absorbent cores and methods of manufacture |
JP7361717B2 (en) | 2018-04-20 | 2023-10-16 | ビーエーエスエフ ソシエタス・ヨーロピア | Thin fluid-absorbent core - absorbent paper |
US20210298962A1 (en) | 2018-08-01 | 2021-09-30 | Basf Se | Feminine hygiene absorbent article |
CN112512476A (en) | 2018-08-01 | 2021-03-16 | 巴斯夫欧洲公司 | Fluid-absorbent core |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5700254A (en) * | 1994-03-31 | 1997-12-23 | Kimberly-Clark Worldwide, Inc. | Liquid distribution layer for absorbent articles |
US20070066754A1 (en) * | 2003-07-25 | 2007-03-22 | Frank Loeker | Powdery water-absorbing polymers with fine particles bound by thermoplastic adhesives |
US20080161522A1 (en) * | 2005-03-30 | 2008-07-03 | Ulrich Riegel | Production of Water-Absorbing Polymeric Particles |
US20080312617A1 (en) * | 2007-06-18 | 2008-12-18 | Harald Hermann Hundorf | Disposable Absorbent Article With Substantially Continuously Distributed Absorbent Particulate Polymer Material And Method |
Family Cites Families (91)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS54130686A (en) * | 1978-03-31 | 1979-10-11 | Sanyo Chem Ind Ltd | Water-absorbing material and its preparation |
JPS6018690B2 (en) | 1981-12-30 | 1985-05-11 | 住友精化株式会社 | Method for improving water absorbency of water absorbent resin |
JPS58180233A (en) | 1982-04-19 | 1983-10-21 | Nippon Shokubai Kagaku Kogyo Co Ltd | Absorbing agent |
US4734478A (en) | 1984-07-02 | 1988-03-29 | Nippon Shokubai Kagaku Kogyo Co., Ltd. | Water absorbing agent |
US4994053A (en) | 1985-06-26 | 1991-02-19 | Kimberly-Clark Corporation | Composite article having discrete particulate areas formed therein |
US5030314A (en) | 1985-06-26 | 1991-07-09 | Kimberly-Clark Corporation | Apparatus for forming discrete particulate areas in a composite article |
DE3713601A1 (en) | 1987-04-23 | 1988-11-10 | Stockhausen Chem Fab Gmbh | METHOD FOR PRODUCING A STRONG WATER-ABSORBENT POLYMER |
US5004761A (en) | 1987-07-28 | 1991-04-02 | Dai-Ichi Kogyo Seiyaku Co., Ltd. | Process for continuously preparing acrylic polymer gel |
JPH0226555A (en) * | 1988-07-17 | 1990-01-29 | Zuikou:Kk | Body fluid absorber |
DE8815855U1 (en) | 1988-12-21 | 1989-02-23 | Hanfspinnerei Steen & Co Gmbh, 2000 Hamburg, De | |
WO1990015830A1 (en) | 1989-06-12 | 1990-12-27 | Weyerhaeuser Company | Hydrocolloid polymer |
US5149335A (en) | 1990-02-23 | 1992-09-22 | Kimberly-Clark Corporation | Absorbent structure |
AU637470B2 (en) | 1990-04-02 | 1993-05-27 | Nippon Shokubai Kagaku Kogyo Co. Ltd. | Method for production of fluid stable aggregate |
DE4020780C1 (en) | 1990-06-29 | 1991-08-29 | Chemische Fabrik Stockhausen Gmbh, 4150 Krefeld, De | |
EP0530438B1 (en) | 1991-09-03 | 1997-02-12 | Hoechst Celanese Corporation | A superabsorbent polymer having improved absorbency properties |
DE4138408A1 (en) | 1991-11-22 | 1993-05-27 | Cassella Ag | HYDROPHILES, HIGHLY SOURCE HYDROGELS |
JP3045422B2 (en) | 1991-12-18 | 2000-05-29 | 株式会社日本触媒 | Method for producing water absorbent resin |
EP0559476B1 (en) | 1992-03-05 | 1997-07-16 | Nippon Shokubai Co., Ltd. | Method for the production of absorbent resin |
GB9208449D0 (en) | 1992-04-16 | 1992-06-03 | Dow Deutschland Inc | Crosslinked hydrophilic resins and method of preparation |
IT1257251B (en) * | 1992-07-03 | 1996-01-10 | Gianfranco Palumbo | THIN STRATIFIED ABSORBENT STRUCTURE, ABSORBENT ITEM INCLUDING SUCH STRUCTURE AND RELATED MANUFACTURING PROCEDURE |
EP0632068B1 (en) | 1993-06-18 | 1998-08-19 | Nippon Shokubai Co., Ltd. | Process for preparing absorbent resin |
US5411497A (en) | 1993-10-29 | 1995-05-02 | Kimberly-Clark Corporation | Absorbent article which includes superabsorbent material located in discrete pockets having an improved containment structure |
CA2116953C (en) | 1993-10-29 | 2003-08-19 | Kimberly-Clark Worldwide, Inc. | Absorbent article which includes superabsorbent material located in discrete elongate pockets placed in selected patterns |
US5425725A (en) | 1993-10-29 | 1995-06-20 | Kimberly-Clark Corporation | Absorbent article which includes superabsorbent material and hydrophilic fibers located in discrete pockets |
US5433715A (en) | 1993-10-29 | 1995-07-18 | Kimberly-Clark Corporation | Absorbent article which includes superabsorbent material located in discrete pockets having water-sensitive and water-insensitive containment structures |
GB9402706D0 (en) | 1994-02-11 | 1994-04-06 | Minnesota Mining & Mfg | Absorbent materials and preparation thereof |
US5494622A (en) | 1994-07-12 | 1996-02-27 | Kimberly-Clark Corporation | Apparatus and method for the zoned placement of superabsorbent material |
US5938650A (en) | 1995-08-09 | 1999-08-17 | Fibertech Group, Inc. | Absorbent core for absorbing body liquids and method |
DE19540951A1 (en) | 1995-11-03 | 1997-05-07 | Basf Ag | Water-absorbent, foam-like, crosslinked polymers, processes for their preparation and their use |
DE19646484C2 (en) | 1995-11-21 | 2000-10-19 | Stockhausen Chem Fab Gmbh | Liquid absorbing polymers, processes for their production and their use |
DE19543368C2 (en) | 1995-11-21 | 1998-11-26 | Stockhausen Chem Fab Gmbh | Water-absorbing polymers with improved properties, processes for their production and their use |
JP3675601B2 (en) * | 1996-09-12 | 2005-07-27 | ユニ・チャーム株式会社 | Absorber |
JPH10137283A (en) * | 1996-11-07 | 1998-05-26 | Oji Paper Co Ltd | Absorptive sheet material |
DE19807502B4 (en) | 1998-02-21 | 2004-04-08 | Basf Ag | Process for post-crosslinking hydrogels with 2-oxazolidinones, hydrogels made therefrom and their use |
US6265488B1 (en) | 1998-02-24 | 2001-07-24 | Nippon Shokubai Co., Ltd. | Production process for water-absorbing agent |
US6503979B1 (en) | 1998-02-26 | 2003-01-07 | Basf Aktiengesellschaft | Method for cross-linking hydrogels with bis- and poly-2-oxazolidinones |
US6847737B1 (en) | 1998-03-13 | 2005-01-25 | University Of Houston System | Methods for performing DAF data filtering and padding |
TW460528B (en) | 1998-04-28 | 2001-10-21 | Nippon Catalytic Chem Ind | Method for production of shaped hydrogel of absorbent resin |
TW438673B (en) | 1998-05-01 | 2001-06-07 | Dow Chemical Co | Method of making a breathable, barrier meltblown nonwoven |
DE19854573A1 (en) | 1998-11-26 | 2000-05-31 | Basf Ag | Process for post-crosslinking hydrogels with 2-oxo-tetrahydro-1,3-oxazines |
DE19854574A1 (en) | 1998-11-26 | 2000-05-31 | Basf Ag | Process for post-crosslinking hydrogels with N-acyl-2-oxazolidinones |
SE517863C2 (en) | 1999-01-22 | 2002-07-23 | Sca Hygiene Prod Ab | Absorbent articles including liquid barriers |
US6610900B1 (en) | 1999-08-27 | 2003-08-26 | Kimberly-Clark Worldwide, Inc. | Absorbent article having superabsorbent in discrete pockets on a stretchable substrate |
US6239230B1 (en) | 1999-09-07 | 2001-05-29 | Bask Aktiengesellschaft | Surface-treated superabsorbent polymer particles |
JP3196933B2 (en) | 1999-09-29 | 2001-08-06 | 株式会社日本吸収体技術研究所 | Water-absorbing composite surface-coated with fibrous hot melt, method for producing the same, and absorbent article |
US6414214B1 (en) | 1999-10-04 | 2002-07-02 | Basf Aktiengesellschaft | Mechanically stable hydrogel-forming polymers |
DE19955861A1 (en) | 1999-11-20 | 2001-05-23 | Basf Ag | Continuous production of crosslinked gel polymer for use e.g. as an absorber involves polymerisation of monomers in a multi-screw machine with heat removal by evaporation of water and product take-off |
JP2001178774A (en) * | 1999-12-24 | 2001-07-03 | Oji Paper Co Ltd | Water absorptive sheet |
JP2002001851A (en) * | 2000-06-19 | 2002-01-08 | Nippon Kyushutai Gijutsu Kenkyusho:Kk | Manufacturing method of highly water absorptive sheetlike composite |
AU2002230831A1 (en) | 2000-10-20 | 2002-04-29 | Millennium Pharmaceuticals, Inc. | Compositions of human proteins and method of use thereof |
US6809158B2 (en) | 2000-10-20 | 2004-10-26 | Nippon Shokubai Co., Ltd. | Water-absorbing agent and process for producing the same |
CN1230410C (en) | 2001-01-12 | 2005-12-07 | 施拖克豪森有限公司 | Continuous method for producing and purifying (meth) acrylic acid |
AU2002338987A1 (en) * | 2001-05-23 | 2002-12-03 | Basf Aktiengesellschaft | Double-sided coated fibrous web absorbent article |
KR20040040487A (en) | 2001-10-05 | 2004-05-12 | 바스프 악티엔게젤샤프트 | Method for Crosslinking Hydrogels wtih Morpholine-2,3-diones |
AU2002349359A1 (en) * | 2001-12-20 | 2003-07-09 | Basf Aktiengesellschaft | Absorbent article |
WO2003065958A1 (en) | 2002-02-04 | 2003-08-14 | Nippon Shokubai Co., Ltd. | Absorptive material, method for producing the same and absorptive article using the same |
DE10204938A1 (en) | 2002-02-07 | 2003-08-21 | Stockhausen Chem Fab Gmbh | Process for post-crosslinking of a water absorbing polymer surface with a cyclic urea useful in foams, fibers, films, cables, especially sealing materials, liquid absorbing hygiene articles, packaging materials, and soil additives |
DE10204937A1 (en) | 2002-02-07 | 2003-08-21 | Stockhausen Chem Fab Gmbh | Process for post-crosslinking of a water absorbing polymer surface with a cyclic urea useful in foams, fibers, films, cables, especially sealing materials and liquid absorbing hygiene articles |
DE10211686A1 (en) | 2002-03-15 | 2003-10-02 | Stockhausen Chem Fab Gmbh | (Meth) acrylic acid crystal and process for the production and purification of aqueous (meth) acrylic acid |
DE10225943A1 (en) | 2002-06-11 | 2004-01-08 | Basf Ag | Process for the preparation of esters of polyalcohols |
CA2488226A1 (en) | 2002-06-11 | 2003-12-18 | Basf Aktiengesellschaft | (meth)acrylic esters of polyalkoxylated trimethylolpropane |
ATE325150T1 (en) | 2002-06-11 | 2006-06-15 | Basf Ag | (METH)ACRYL ESTER OF POLYALKOXYLATED GLYCERIN |
DE10247240A1 (en) | 2002-10-10 | 2004-04-22 | Basf Ag | Process for the production of acrylic acid |
ES2428693T3 (en) | 2003-02-12 | 2013-11-08 | The Procter & Gamble Company | Absorbent core for an absorbent article |
ATE523180T1 (en) | 2003-02-12 | 2011-09-15 | Procter & Gamble | ABSORBENT CORE FOR AN ABSORBENT ARTICLE |
DE10331456A1 (en) | 2003-07-10 | 2005-02-24 | Basf Ag | (Meth) acrylic esters of alkoxylated unsaturated polyol ethers and their preparation |
DE10331450A1 (en) | 2003-07-10 | 2005-01-27 | Basf Ag | (Meth) acrylic esters of monoalkoxylated polyols and their preparation |
DE10334584A1 (en) | 2003-07-28 | 2005-02-24 | Basf Ag | Post crosslinking of water absorbing polymers, useful for hygiene articles and packaging, comprises treatment with a bicyclic amideacetal crosslinking agent with simultaneous or subsequent heating |
EP1504772A1 (en) * | 2003-08-06 | 2005-02-09 | The Procter & Gamble Company | Superabsorbent polymers having radiation activable surface cross-linkers and method of making them |
US20050097025A1 (en) | 2003-10-31 | 2005-05-05 | Horton Bruce M. | System and method for settling transactions on an eroding basis |
DE10355401A1 (en) | 2003-11-25 | 2005-06-30 | Basf Ag | (Meth) acrylic esters of unsaturated amino alcohols and their preparation |
US7662745B2 (en) | 2003-12-18 | 2010-02-16 | Kimberly-Clark Corporation | Stretchable absorbent composites having high permeability |
US20050256757A1 (en) | 2004-04-30 | 2005-11-17 | Sierra Alisa K | Method of manufacturing and method of marketing gender-specific absorbent articles having liquid-handling properties tailored to each gender |
US7772456B2 (en) | 2004-06-30 | 2010-08-10 | Kimberly-Clark Worldwide, Inc. | Stretchable absorbent composite with low superaborbent shake-out |
PL1621166T5 (en) * | 2004-07-28 | 2019-06-28 | The Procter And Gamble Company | Process for producing absorbent core structures |
US20070135785A1 (en) | 2005-12-12 | 2007-06-14 | Jian Qin | Absorbent articles comprising thermoplastic coated superabsorbent polymer materials |
WO2008040715A2 (en) | 2006-10-05 | 2008-04-10 | Basf Se | Method for the production of water absorbent polymer particles by polymerizing drops of a monomer solution |
WO2008052971A1 (en) | 2006-10-31 | 2008-05-08 | Basf Se | Regulation of a process for producing water-absorbing polymer particles in a heated gas phase |
US8314173B2 (en) | 2007-01-29 | 2012-11-20 | Basf Se | Method for producing white and color-stable water-absorbing polymer particles having high absorbency and high saline flow conductivity |
CN101677891B (en) | 2007-06-18 | 2013-11-27 | 宝洁公司 | Tri-folded disposable absorbent article, packaged absorbent article, and array of packaged absorbent articles with substantially continuously distributed absorbent particulate polymer material |
EP2157956B1 (en) | 2007-06-18 | 2013-07-17 | The Procter and Gamble Company | Disposable absorbent article with sealed absorbent core with substantially continuously distributed absorbent particulate polymer material |
EP2157953B1 (en) | 2007-06-18 | 2015-07-15 | The Procter and Gamble Company | Better fitting disposable absorbent article with substantially continuously distributed absorbent particulate polymer material |
EP2157951B1 (en) | 2007-06-18 | 2015-09-02 | The Procter & Gamble Company | Disposable absorbent article with enhanced absorption properties with substantially continuously distributed absorbent particulate polymer material |
US8017827B2 (en) | 2007-06-18 | 2011-09-13 | The Procter & Gamble Company | Disposable absorbent article with enhanced absorption properties |
CA2692238A1 (en) | 2007-06-18 | 2008-12-24 | Harald Hermann Hundorf | Disposable absorbent article with improved acquisition system with substantially continuously distributed absorbent particulate polymer material |
ES2409836T3 (en) * | 2007-08-10 | 2013-06-28 | The Procter & Gamble Company | Absorbent article |
WO2010015591A1 (en) * | 2008-08-06 | 2010-02-11 | Basf Se | Fluid-absorbent articles |
US8895800B2 (en) * | 2008-08-06 | 2014-11-25 | Basf Se | Fluid absorbent articles |
US8669410B2 (en) * | 2008-08-06 | 2014-03-11 | Basf Se | Fluid-absorbent articles |
CN102438665B (en) | 2009-05-20 | 2016-04-27 | 巴斯夫欧洲公司 | Water-absorbent storage layers |
DE202011111011U1 (en) | 2010-10-13 | 2018-03-28 | Drylock Technologies Nv | Absorbing structure |
-
2010
- 2010-05-17 CN CN201080022189.4A patent/CN102438665B/en active Active
- 2010-05-17 EP EP10719351.8A patent/EP2432511B1/en not_active Revoked
- 2010-05-17 WO PCT/EP2010/056688 patent/WO2010133529A2/en active Application Filing
- 2010-05-17 JP JP2012511244A patent/JP2012527267A/en active Pending
- 2010-05-17 US US13/319,591 patent/US20120064792A1/en not_active Abandoned
- 2010-05-17 EP EP20130158897 patent/EP2609939B1/en not_active Revoked
-
2015
- 2015-06-29 US US14/753,511 patent/US9585798B2/en active Active
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5700254A (en) * | 1994-03-31 | 1997-12-23 | Kimberly-Clark Worldwide, Inc. | Liquid distribution layer for absorbent articles |
US20070066754A1 (en) * | 2003-07-25 | 2007-03-22 | Frank Loeker | Powdery water-absorbing polymers with fine particles bound by thermoplastic adhesives |
US20080161522A1 (en) * | 2005-03-30 | 2008-07-03 | Ulrich Riegel | Production of Water-Absorbing Polymeric Particles |
US20080312617A1 (en) * | 2007-06-18 | 2008-12-18 | Harald Hermann Hundorf | Disposable Absorbent Article With Substantially Continuously Distributed Absorbent Particulate Polymer Material And Method |
Cited By (81)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US11234868B2 (en) | 2003-02-12 | 2022-02-01 | The Procter & Gamble Company | Comfortable diaper |
US10660800B2 (en) | 2003-02-12 | 2020-05-26 | The Procter & Gamble Company | Comfortable diaper |
US10470948B2 (en) | 2003-02-12 | 2019-11-12 | The Procter & Gamble Company | Thin and dry diaper |
US9763835B2 (en) | 2003-02-12 | 2017-09-19 | The Procter & Gamble Company | Comfortable diaper |
US11135096B2 (en) | 2003-02-12 | 2021-10-05 | The Procter & Gamble Company | Comfortable diaper |
US11793682B2 (en) | 2003-02-12 | 2023-10-24 | The Procter & Gamble Company | Thin and dry diaper |
US9060904B2 (en) | 2007-06-18 | 2015-06-23 | The Procter & Gamble Company | Disposable absorbent article with sealed absorbent core with substantially continuously distributed absorbent particulate polymer material |
US9072634B2 (en) | 2007-06-18 | 2015-07-07 | The Procter & Gamble Company | Disposable absorbent article with substantially continuously distributed absorbent particulate polymer material and method |
US9241845B2 (en) | 2007-06-18 | 2016-01-26 | The Procter & Gamble Company | Disposable absorbent article with sealed absorbent core with substantially continuously distributed absorbent particulate polymer material |
US9326896B2 (en) | 2008-04-29 | 2016-05-03 | The Procter & Gamble Company | Process for making an absorbent core with strain resistant core cover |
US9585798B2 (en) | 2009-05-20 | 2017-03-07 | Basf Se | Water absorbent storage layers |
US10004647B2 (en) | 2009-12-02 | 2018-06-26 | The Procter & Gamble Company | Apparatus and method for transferring particulate material |
US9340363B2 (en) | 2009-12-02 | 2016-05-17 | The Procter & Gamble Company | Apparatus and method for transferring particulate material |
US10813794B2 (en) | 2011-06-10 | 2020-10-27 | The Procter & Gamble Company | Method and apparatus for making absorbent structures with absorbent material |
US10149788B2 (en) | 2011-06-10 | 2018-12-11 | The Procter & Gamble Company | Disposable diapers |
US9492328B2 (en) | 2011-06-10 | 2016-11-15 | The Procter & Gamble Company | Method and apparatus for making absorbent structures with absorbent material |
US11602467B2 (en) | 2011-06-10 | 2023-03-14 | The Procter & Gamble Company | Absorbent structure for absorbent articles |
US11911250B2 (en) | 2011-06-10 | 2024-02-27 | The Procter & Gamble Company | Absorbent structure for absorbent articles |
US9649232B2 (en) | 2011-06-10 | 2017-05-16 | The Procter & Gamble Company | Disposable diaper having reduced absorbent core to backsheet gluing |
US9668926B2 (en) | 2011-06-10 | 2017-06-06 | The Procter & Gamble Company | Method and apparatus for making absorbent structures with absorbent material |
US11135105B2 (en) | 2011-06-10 | 2021-10-05 | The Procter & Gamble Company | Absorbent structure for absorbent articles |
US9173784B2 (en) | 2011-06-10 | 2015-11-03 | The Procter & Gamble Company | Disposable diaper having reduced absorbent core to backsheet gluing |
US11110011B2 (en) | 2011-06-10 | 2021-09-07 | The Procter & Gamble Company | Absorbent structure for absorbent articles |
US10517777B2 (en) | 2011-06-10 | 2019-12-31 | The Procter & Gamble Company | Disposable diaper having first and second absorbent structures and channels |
US9468566B2 (en) | 2011-06-10 | 2016-10-18 | The Procter & Gamble Company | Absorbent structure for absorbent articles |
US9066838B2 (en) | 2011-06-10 | 2015-06-30 | The Procter & Gamble Company | Disposable diaper having reduced absorbent core to backsheet gluing |
US11000422B2 (en) | 2011-06-10 | 2021-05-11 | The Procter & Gamble Company | Method and apparatus for making absorbent structures with absorbent material |
US9974699B2 (en) | 2011-06-10 | 2018-05-22 | The Procter & Gamble Company | Absorbent core for disposable absorbent articles |
US10893987B2 (en) | 2011-06-10 | 2021-01-19 | The Procter & Gamble Company | Disposable diapers with main channels and secondary channels |
US10245188B2 (en) | 2011-06-10 | 2019-04-02 | The Procter & Gamble Company | Method and apparatus for making absorbent structures with absorbent material |
US10561546B2 (en) | 2011-06-10 | 2020-02-18 | The Procter & Gamble Company | Absorbent structure for absorbent articles |
US10130525B2 (en) | 2011-06-10 | 2018-11-20 | The Procter & Gamble Company | Absorbent structure for absorbent articles |
US20150080822A1 (en) * | 2011-06-17 | 2015-03-19 | The Procter & Gamble Company | Absorbent article having improved absorption properties |
US9345624B2 (en) * | 2011-06-17 | 2016-05-24 | The Procter & Gamble Company | Absorbent article having improved absorption properties |
US11000430B2 (en) | 2011-06-17 | 2021-05-11 | The Procter & Gamble Company | Absorbent article having improved absorption properties |
US10028867B2 (en) | 2011-06-17 | 2018-07-24 | The Procter & Gamble Company | Absorbent article having improved absorption properties |
JP2015521678A (en) * | 2012-07-03 | 2015-07-30 | ビーエーエスエフ ソシエタス・ヨーロピアBasf Se | Process for producing water-absorbing polymer particles with improved properties |
US10449097B2 (en) | 2012-11-13 | 2019-10-22 | The Procter & Gamble Company | Absorbent articles with channels and signals |
US9532910B2 (en) | 2012-11-13 | 2017-01-03 | The Procter & Gamble Company | Absorbent articles with channels and signals |
US10022280B2 (en) | 2012-12-10 | 2018-07-17 | The Procter & Gamble Company | Absorbent article with high absorbent material content |
US9216118B2 (en) | 2012-12-10 | 2015-12-22 | The Procter & Gamble Company | Absorbent articles with channels and/or pockets |
US8979815B2 (en) | 2012-12-10 | 2015-03-17 | The Procter & Gamble Company | Absorbent articles with channels |
US9216116B2 (en) | 2012-12-10 | 2015-12-22 | The Procter & Gamble Company | Absorbent articles with channels |
US9375358B2 (en) | 2012-12-10 | 2016-06-28 | The Procter & Gamble Company | Absorbent article with high absorbent material content |
US9713557B2 (en) | 2012-12-10 | 2017-07-25 | The Procter & Gamble Company | Absorbent article with high absorbent material content |
US9713556B2 (en) | 2012-12-10 | 2017-07-25 | The Procter & Gamble Company | Absorbent core with high superabsorbent material content |
US10966885B2 (en) | 2012-12-10 | 2021-04-06 | The Procter & Gamble Company | Absorbent article with high absorbent material content |
US10639215B2 (en) | 2012-12-10 | 2020-05-05 | The Procter & Gamble Company | Absorbent articles with channels and/or pockets |
US10071002B2 (en) | 2013-06-14 | 2018-09-11 | The Procter & Gamble Company | Absorbent article and absorbent core forming channels when wet |
US11273086B2 (en) | 2013-06-14 | 2022-03-15 | The Procter & Gamble Company | Absorbent article and absorbent core forming channels when wet |
US9987176B2 (en) | 2013-08-27 | 2018-06-05 | The Procter & Gamble Company | Absorbent articles with channels |
US10765567B2 (en) | 2013-08-27 | 2020-09-08 | The Procter & Gamble Company | Absorbent articles with channels |
US10736794B2 (en) | 2013-08-27 | 2020-08-11 | The Procter & Gamble Company | Absorbent articles with channels |
US11406544B2 (en) | 2013-08-27 | 2022-08-09 | The Procter & Gamble Company | Absorbent articles with channels |
US10335324B2 (en) | 2013-08-27 | 2019-07-02 | The Procter & Gamble Company | Absorbent articles with channels |
US11759376B2 (en) | 2013-08-27 | 2023-09-19 | The Procter & Gamble Company | Absorbent articles with channels |
US9789011B2 (en) | 2013-08-27 | 2017-10-17 | The Procter & Gamble Company | Absorbent articles with channels |
US11612523B2 (en) | 2013-08-27 | 2023-03-28 | The Procter & Gamble Company | Absorbent articles with channels |
US10292875B2 (en) | 2013-09-16 | 2019-05-21 | The Procter & Gamble Company | Absorbent articles with channels and signals |
US11207220B2 (en) | 2013-09-16 | 2021-12-28 | The Procter & Gamble Company | Absorbent articles with channels and signals |
US11944526B2 (en) | 2013-09-19 | 2024-04-02 | The Procter & Gamble Company | Absorbent cores having material free areas |
US10130527B2 (en) | 2013-09-19 | 2018-11-20 | The Procter & Gamble Company | Absorbent cores having material free areas |
US11154437B2 (en) | 2013-09-19 | 2021-10-26 | The Procter & Gamble Company | Absorbent cores having material free areas |
US10828206B2 (en) | 2013-12-19 | 2020-11-10 | Procter & Gamble Company | Absorbent articles having channel-forming areas and wetness indicator |
US10675187B2 (en) | 2013-12-19 | 2020-06-09 | The Procter & Gamble Company | Absorbent articles having channel-forming areas and wetness indicator |
US9789009B2 (en) | 2013-12-19 | 2017-10-17 | The Procter & Gamble Company | Absorbent articles having channel-forming areas and wetness indicator |
US11191679B2 (en) | 2013-12-19 | 2021-12-07 | The Procter & Gamble Company | Absorbent articles having channel-forming areas and wetness indicator |
US11090199B2 (en) | 2014-02-11 | 2021-08-17 | The Procter & Gamble Company | Method and apparatus for making an absorbent structure comprising channels |
US10441481B2 (en) | 2014-05-27 | 2019-10-15 | The Proctre & Gamble Company | Absorbent core with absorbent material pattern |
US10052242B2 (en) | 2014-05-27 | 2018-08-21 | The Procter & Gamble Company | Absorbent core with absorbent material pattern |
US10507144B2 (en) | 2015-03-16 | 2019-12-17 | The Procter & Gamble Company | Absorbent articles with improved strength |
US10322040B2 (en) | 2015-03-16 | 2019-06-18 | The Procter & Gamble Company | Absorbent articles with improved cores |
US11918445B2 (en) | 2015-05-12 | 2024-03-05 | The Procter & Gamble Company | Absorbent article with improved core-to-backsheet adhesive |
US10736795B2 (en) | 2015-05-12 | 2020-08-11 | The Procter & Gamble Company | Absorbent article with improved core-to-backsheet adhesive |
US11497657B2 (en) | 2015-05-29 | 2022-11-15 | The Procter & Gamble Company | Absorbent articles having channels and wetness indicator |
US10543129B2 (en) | 2015-05-29 | 2020-01-28 | The Procter & Gamble Company | Absorbent articles having channels and wetness indicator |
US10632029B2 (en) | 2015-11-16 | 2020-04-28 | The Procter & Gamble Company | Absorbent cores having material free areas |
US11123240B2 (en) | 2016-04-29 | 2021-09-21 | The Procter & Gamble Company | Absorbent core with transversal folding lines |
US10842690B2 (en) | 2016-04-29 | 2020-11-24 | The Procter & Gamble Company | Absorbent core with profiled distribution of absorbent material |
AU2016430853B2 (en) * | 2016-11-30 | 2022-09-29 | Kimberly-Clark Worldwide, Inc. | Three-dimensional functional structure |
US11957551B2 (en) | 2021-11-16 | 2024-04-16 | The Procter & Gamble Company | Absorbent articles with channels and signals |
Also Published As
Publication number | Publication date |
---|---|
JP2012527267A (en) | 2012-11-08 |
EP2609939A1 (en) | 2013-07-03 |
WO2010133529A3 (en) | 2011-03-10 |
US9585798B2 (en) | 2017-03-07 |
EP2432511A2 (en) | 2012-03-28 |
EP2609939B1 (en) | 2014-10-29 |
EP2432511B1 (en) | 2013-07-24 |
CN102438665B (en) | 2016-04-27 |
US20150359688A1 (en) | 2015-12-17 |
CN102438665A (en) | 2012-05-02 |
WO2010133529A2 (en) | 2010-11-25 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US9585798B2 (en) | Water absorbent storage layers | |
US9822197B2 (en) | Method for producing superabsorbers based on renewable raw materials | |
US20100247916A1 (en) | Process for Producing Surface Postcrosslinked Water-Absorbing Polymer Particles | |
US8410221B2 (en) | Process for producing water-absorbing polymer particles with low caking tendency and high absorption under pressure | |
JP6138056B2 (en) | Process for producing water-absorbing polymer particles having a high swelling rate | |
US8372765B2 (en) | Odor inhibiting water-absorbing composites | |
JP6124874B2 (en) | Use of water-absorbing polymer particles to absorb blood and / or menstrual fluid | |
US20110257340A1 (en) | Process for Producing Water-Absorbing Polymer Particles | |
US8608096B2 (en) | Method for the production of water-absorbing polymer particles | |
US8703876B2 (en) | Process for producing water absorbing polymer particles with improved color stability | |
US9587081B2 (en) | Water-absorbing polymer particles with high free swell rate and high permeability | |
US8497337B2 (en) | Process for producing water-absorbing polymer particles with improved color stability | |
US9833769B2 (en) | Process for producing water-absorbing polymer particles with high free swell rate | |
US8765898B2 (en) | Process for producing water-absorbing polymer particles | |
US20120308507A1 (en) | Odor-Inhibiting Mixtures for Incontinence Articles | |
KR102358726B1 (en) | Water-absorbing polymer particles | |
EP2838572A1 (en) | Process for producing surface postcrosslinked water-absorbing polymer particles | |
US9751958B2 (en) | Use of heating steam condensate for producing water-absorbent polymer particles | |
EP3331922A1 (en) | Process for producing superabsorbents | |
US20120184690A1 (en) | Method for Continuous Production of Water-Absorbent Polymer Particles |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: BASF SE, GERMANY Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:BAUDUIN, CHRISTOPHE;REEL/FRAME:027721/0353 Effective date: 20100623 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |