Microfiber-containing absorbent structures and absorbent articles
AssigneeThe Procter & Gamble Company
InventorsMark D. Seymour, Michael F. LiCause, Thomas H. Daugherty
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Abstract
The present invention relates to absorbent web structures suitable for incorporation into absorbent articles such as sanitary napkins, diapers, incontinent devices, training pants and the like. Such structures comprised webs of entangled melt blown microfibers which are prepared from a particular type of hydrophilic nylon copolymer. Preferred hydrophilic cylon microfiber-based webs also contain staple fibers and/or particles of hydrogel-forming polymeric gelling agent. Web structures containing hydrophilic nylon microfibers have specially desirable comfort, integrity and fluid handling characteristics.
Claims17
An absorbent structure especially suitable for acquiring and distributing aqueous fluids throughout such a structure, which structure comprises an entangled web of melt-blown microfibers having diameters which range from about 0.5 to 60 microns, said microfibers being formed from a thermoplastic copolymer comprising a nylon component and a hydrophilizing polymeric component which renders said copolymer hydrophilic and which provides a copolymer having a melting point of from about 100.degree. C. to 265.degree. C. and a melt viscosity of from about 1 to 400 Pa-sec.;
- said web having a dry density of from about 0.006 to 0.3 g/cm.sup.3.
An absorbent composite structure especially suitable for use in disposable absorbent articles of improved comfort, wet integrity and fluid handling characteristics, said composite structure comprising
- (A) from about 14% to 85% by weight of the composite of hydrophilic nylon melt blown microfibers, substantially all of which are of a diameter of from about 0.5 to 60 microns, said microfibers being formed from a thermoplastic copolymer comprising a nylon component and a hydrophilizing polymeric component which renders said copolymer hydrophilic and which provides a copolymer having a melting point of from about 100.degree. C. to 265.degree. C. and a melt viscosity of from about 1 to 400 Pa-sec.;
- (B) from about 10% to 85% by weight of the composite of substantially nonabsorbent synthetic staple fibers, substantially all of which have a denier of from about 5 to 70 and a percent crimp of at least about 15%, said staple fibers being formed from a synthetic polymeric material having a modulus value when dry of at least about 0.1.times.10.sup.10 dynes/cm.sup.2, said modulus value not diminishing significantly when said staple fibers are wet;
- and
- (C) from about 1% to 55% by weight of the composite of nonfibrous particles of a hydrogel-forming polymeric gelling agent having an equilibrium gel volume of at least about 20 grams of synthetic urine or artificial menses per gram of gelling agent, substantially all of said polymeric gelling agent particles ranging in diameter from about 10 microns to 2 mm;
- said hydrophilic nylon melt blown microfibers, staple fibers and polymeric gelling agent particles being combined in a manner which forms a composite web having a dry density of from about 0.006 to 0.3 g/cm.sup.3.
An absorbent article of improved comfort, wet integrity and fluid handling characteristics, said article comprising:
- (A) a liquid impervious backing sheet;
- (B) a liquid pervious topsheet;
- and
- (C) an absorbent core positioned between said backing sheet and said topsheet, said absorbent core containing an absorbent structure which comprises an entangled web of melt-blown microfibers having diameters which range from about 0.5 to 60 microns, said microfibers being formed from a thermoplastic copolymer comprising a nylon component and a hydrophilizing polymeric component which renders said copolymer hydrophilic and which provides a copolymer having a melting point of from about 100.degree. C. to 265.degree. C. and a melt viscosity of from about 1 to 400 Pa-sec.;
- said web having a dry density of from about 0.006 to 0.3 g/cm.sup.3.
Dependencies are inferred from the claim text.