Absorbent resin particles and absorbent

Patent metadata

Field	Value
Publication number	US-12351692-B2
Application number	US-202017757136-A
Country	US
Kind code	B2
Filing date	Dec 9, 2020
Priority date	Dec 13, 2019
Publication date	Jul 8, 2025
Grant date	Jul 8, 2025

Abstract

The present disclosure relates to water-absorbent resin particles in which a contact angle of 0.9% by mass saline at 25° C.±2° C. is 100 degrees or larger, and an absorbent material containing the water-absorbent resin particles.

First claim

The invention claimed is:

1. An absorbent material comprising water-absorbent resin particles, wherein the water-absorbent resin particles comprise a polymer particle having water absorption properties; and a coating layer that coats at least a part of a surface of the polymer particle and contains a water-insoluble component that is at least one selected from the group consisting of polyolefins, polyurethanes, and acid-modified products thereof,
the water-absorbent resin particles have a water absorption rate by a Vortex method of 55 seconds or more,
the water-absorbent resin particles have a water retention amount of physiological saline of 35 g/g to 60 g/g, and
the water-absorbent resin particles have a contact angle with 0.9% by mass saline at 25° C.±2° C. of 100 degrees or larger and 130 degrees or smaller.

2. The absorbent material according to claim 1 , wherein the water-absorbent resin particles have a water absorption rate by a Vortex method of 58 seconds or more.

3. The absorbent material according to claim 1 , wherein the water-absorbent resin particles have a contact angle with 0.9% by mass saline at 25° C.±2° C. of 120 degrees or smaller and 100 degrees or larger.

4. The absorbent material according to claim 1 , wherein the water-absorbent resin particles have a water absorption rate by a Vortex method of 61 seconds or more.

5. The absorbent material according to claim 1 , wherein a ratio of a coating material used to form the coating layer is 0.01% by mass to 20% by mass.

6. The absorbent material according to claim 1 , wherein the water-absorbent resin particles have a water retention amount of physiological saline of 39 g/g to 45 g/g.

7. The absorbent material according to claim 1 , wherein the polyolefins include at least one selected from the group consisting of polyethylene, polypropylene, and an ethylene-propylene copolymer.

8. The absorbent material according to claim 1 , wherein the polyurethanes include a reaction product of polyol and polyisocyanate, and the polyisocyanate is aromatic isocyanate.

9. The absorbent material according to claim 1 , further comprising a fibrous substance.

10. The absorbent material according to claim 9 , wherein the water-absorbent resin particles are mixed with the fibrous substance.

11. The absorbent material according to claim 9 , wherein the water-absorbent resin particles define a layer sandwiched by the fibrous substance.

12. The absorbent material according to claim 9 , wherein the fibrous substance comprises at least one selected from the group consisting of wood pulp, cotton, cotton linter, rayon, cellulose acetate, polyamide, polyester, and polyolefin.

13. The absorbent material according to claim 9 , wherein fibers of the fibrous substance are adhered to each other with an adhesive binder.

14. The absorbent material of claim 9 , which is in a form of a sheet having a thickness in the range of 0.1 to 20 mm.

15. An absorbent article comprising the absorbent material of claim 1 and a core wrap surrounding the absorbent material.

16. The absorbent article of claim 15 , wherein the core wrap is disposed between a liquid permeable sheet and a liquid impermeable sheet.

Assignees

• Sumitomo Seika Chemicals

Inventors

• Kobayashi Tetsuhiro
• SAWAKI Hiroki

Classifications

• B01J20/28016

  Particle form · CPC title

• B01J20/264

  derived from different types of monomers, e.g. linear or branched copolymers, block copolymers, graft copolymers · CPC title

• B01J20/262

  obtained otherwise than by reactions only involving carbon to carbon unsaturated bonds, e.g. obtained by polycondensation (macromolecular compounds obtained otherwise than by reactions only involving unsaturated carbon-to-carbon bonds per se C08G) · CPC title

• B01J20/24

  Naturally occurring macromolecular compounds, e.g. humic acids or their derivatives · CPC title

• C08L101/14

  the macromolecular compounds being water soluble or water swellable, e.g. aqueous gels · CPC title