Water-absorbing resin particles and absorbent article

Patent metadata

Field	Value
Publication number	US-12246303-B2
Application number	US-201917298822-A
Country	US
Kind code	B2
Filing date	Dec 12, 2019
Priority date	Dec 12, 2018
Publication date	Mar 11, 2025
Grant date	Mar 11, 2025

Abstract

Water-absorbing resin particles, in which a light transmittance at a wavelength of 425 nm when the water-absorbing resin particles are swollen 30 times with a physiological saline solution is 20% or more, are disclosed.

First claim

The invention claimed is:

1. Water-absorbing resin particles comprising:
a crosslinked polymer having a monomer unit derived from an ethylenically unsaturated monomer comprising at least one compound selected from the group consisting of (meth)acrylic acid and a salt thereof,
wherein a proportion of a (meth)acrylic acid and a salt thereof is 70 to 100 mol % with respect to a total amount of monomers in the crosslinked polymer,
a light transmittance at a wavelength of 425 nm when the water-absorbing resin particles are swollen 30 times with a physiological saline solution is 20% or more, and
a water retention capacity for the physiological saline solution is 30 to 55 g/g.

2. An absorbent article comprising:
a liquid-impermeable sheet;
an absorbent; and
a liquid-permeable sheet,
wherein the liquid-impermeable sheet, the absorbent, and the liquid-permeable sheet are disposed in this order, and
the absorbent comprises the water-absorbing resin particles according to claim 1 .

3. The absorbent article according to claim 2 , wherein the liquid-permeable sheet comprises thermal bonded non-woven fabrics, air through non-woven fabrics, resin bonded non-woven fabrics, spunbond non-woven fabrics, melt-blown non-woven fabrics, airlaid non-woven fabrics, spunlace non-woven fabrics, point-bonded non-woven fabrics, or a laminate of two or more of non-woven fabrics selected from these non-woven fabrics.

4. The absorbent article according to claim 2 , wherein the absorbent further comprises a fibrous material.

5. The absorbent article according to claim 2 , further comprising a core wrap that covers at least a surface side of the absorbent in contact with the liquid-permeable sheet.

6. The absorbent article according to claim 5 , wherein the core wrap is adhered to the liquid-permeable sheet.

7. The absorbent article according to claim 2 ,
wherein the absorbent is disposed to be in contact with the liquid-permeable sheet, and
the absorbent is adhered to the liquid-permeable sheet.

8. The absorbent article according to claim 2 , wherein a water absorption speed of the water-absorbing resin particles for a physiological saline solution is 30 to 80 seconds.

9. The water-absorbing resin particles according to claim 1 ,
wherein the light transmittance at a wavelength of 425 nm when the water-absorbing resin particles are swollen 30 times with a physiological saline solution is 50% or more.

10. The water-absorbing resin particles according to claim 1 ,
wherein a median particle size of the water-absorbing resin particles is 250 to 850 μm.

Assignees

• Sumitomo Seika Chemicals

Inventors

• Ito Takashi

Classifications

• G01N21/59

  Transmissivity (G01N21/25 takes precedence) · CPC title

• B01J20/28016 Primary

  Particle form · CPC title

• B01J20/28004

  Sorbent size or size distribution, e.g. particle size · CPC title

• A61L15/24

  Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds; Derivatives thereof {(A61L15/225 takes precedence)} · CPC title

• A61F2013/53908

  with adhesive · CPC title