Kao Corporation

Kao Soap Company, Ltd.

Osamu Ito

Kazunori Nishizawa

Hiroshi Mizutani

Harumasa Yamasaki

Iwao Miyashita

Akira Sakurai

Takatoshi Kobayashi

Daisuke Shiba

Yuzo Sumida

Itsuo Minakata

In a sanitary article having as a core material a super water absorbing polymer and two layers of fluff pulp to envelop the polymer, the improvement comprises that said layer of fluff pulp is composed of a compressed first site and a further compressed second site, the density of said first site ranging from 0.04 to 0.15 g/cm.sup.3, the density of said second site ranging from 0.06 to 0.4 g/cm.sup.3, and the area of said second site ranging from 10 to 50% of that of the entire article.

Sanitary article

In an absorbent article which comprises a liquid-impermeable, leakproof sheet, a liquid-permeable surface sheet and an absorbent layer, the leakproof sheet is a porous film, monoaxially or biaxially stretched, of a polyolefin resin composition comprising a polyolefin and a filler, having a thickness of not larger than 60 microns, an average pore size of 0.05 to 5 microns, a pore volume of not smaller than 0.1 cm.sup.3 per 1 cm.sup.3 of the film, a water vapor permeability of not smaller than 500 g/m.sup.2 for 24 hours and a bending resistance at either longitudinal or transversal directions to meet the following definition:

Absorbent article

A sanitary, liquid-absorbing article has as surface material a non-woven fabric comprising two layers integrated by a binder, the first layer having a basis weight of 5 to 15 g/m.sup.2, the second layer having a basis weight of 20 to 45 g/m.sup.2, wherein when the non-woven fabric is in the wet state, E=K.rho..sub.F.sup.a ; .rho..sub.FO .ltoreq.1.2.times.10.sup.-2 g/cm.sup.3 ; and K.gtoreq.1.2.times.10.sup.6 as defined in the following compression characteristic formula of the non-woven fabric: ##EQU1## wherein E is a Young's modulus (g/cm.sup.2), P is a pressure (g/cm.sup.2), .rho..sub.F is an apparent specific weight (g/cm.sup.3) and .rho..sub.FO is a .rho..sub.F value when the pressure is 0 g/cm.sup.2.

Water absorbing article

A polymer in the form of particles is water-insoluble and water-sellable, containing carboxyl or carboxylate groups. It has a physiological saline absorption quantity of 40 to 90 grams per one gram of the polymer, a physiological saline absorption rate of at least 8 ml per 0.3 gram of the polymer, a gel strength of 33 to 200 g/cm2 when it has been swollen to saturation with ion-exchange water. It is useful as an absorbent in a sanitary article.

Absorptive material

An absorbent article such as a sanitary napkin and a diaper is improved in the surface material by use of a non-woven fabric of hot-melt fibers which melts at 90.degree. to 140.degree. C. It is disposable.

A disposable diaper comprises a liquid-permeable surface sheet, a liquid-impermeable backing sheet, and an absorbent pad sandwiched between the two sheets, characterized in that water-absorptive, shrinkable fiber strings, which contract lengthwise on contact with water and are rendered stretchable, are secured to the two sheets, extending midway longitudinally of the diaper in parallel along, but without overlapping, the both edges of the pad, the edge portions of the surface sheet outside the water-absorptive, shrinkable fiber strings and the surface sheet portion on the absorbent pad being partly bonded together at two spots about halfway of the length, the distance between the two bonded spots being at least 50 mm and the bonded spots themselves being 10 to 50 mm long each, and elastic, stretch members, at least 70 mm long each and having a combined elastic force or tensile strength (the weight equivalent to the force required to stretch the diaper including any shrank portions thereof up to the total diaper length) of 20 to 600 g, are provided midway and longitudinally of the both edge portions of the diaper at least 5 mm outside the both bonded spots.

Disposable diaper

The twisted yarn is prepared by twisting (1) a single yarn comprising a water-insoluble fiber having a degree of water swelling of at least 10 cc/g or (2) a plurality of single yarns comprising a water-insoluble fiber having a degree of water swelling of at least 10 cc/g or a plurality of yarns comprising at least 50% by weight of such single yarns and water-nonswellable yarns so that the twist constant is at least 2.5.

Twisted yarn

A disposable diaper is disclosed which comprises a liquid-permeable surface sheet, a liquid-impermeable back face sheet and a water-absorbing layer disposed between said sheets, wherein water-absorbing shrinkable fibers, the length of which is reduced on contact with water to impart elasticity to the fibers, are fixed across the central portion of the diaper in the lengthwise direction of the diaper without being lapped over the water-absorbing layer and said water-absorbing layer is connected to said water-absorbing shrinkable fibers by cellulose fibers.

A twisted combination yarn is disclosed which is made of a first yarn which contracts when it absorbs water, and a second yarn plied with the first yarn which is not substantially changed in length by contact with water. The twisted combination yarn of the invention has a high water absorbing capacity, and contracts and becomes elastic when it absorbs water.

Twisted yarn and twisted bundle of yarns

An absorbent article comprising an upper, first, absorbing layer formed so that its density under a load of 35 g/cm.sup.2 is lower than 0.045 g/cm.sup.3 both in the dry state and in the wet state and the weight per square meter is 15 to 50 g, and a lower, second, absorbing layer having a super water-absorbing polymer fixed thereto.

Two layer absorbent article with super water-absorbing polymer

A disposable diaper comprising a water-absorbing layer located between a liquid-permeable surface sheet and a liquid-impermeable backing sheet, wherein water-absorbing shrinkable fibers, which shrink in the direction of the fiber length and are rendered elastic on absorption of water, are fixed to and extend along the central portion in the lengthwise direction of the disposable diaper in such a manner that the water-absorbing shrinkable fibers are not placed on top of the water-absorbing layer, and wherein means is provided so that the water-absorbing shrinkable fibers become wetted when the diaper is wetted, said water-absorbing shrinkable fibers exhibiting a percent shrinkage of at least 15% and a shrinking force of at least 100 g when said fibers are wetted.

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Utsunomiya, Japan

Osamu Ito