Coated resin particles and method for producing coated resin particles

Patent metadata

Field	Value
Publication number	US-12590190-B2
Application number	US-202017757135-A
Country	US
Kind code	B2
Filing date	Dec 9, 2020
Priority date	Dec 13, 2019
Publication date	Mar 31, 2026
Grant date	Mar 31, 2026

Abstract

One aspect of the present invention relates to a coated resin particle including: a water-absorbent resin particle; and a coating layer that coats at least a part of a surface of the water-absorbent resin particle, in which the coating layer contains a water-soluble component in which a solubility in 100 g of water is in a range of 1.0 g or more and 150 g or less at 25° C.

First claim

The invention claimed is:

1 . A coated resin particle comprising:
a water-absorbent resin particle; and a coating layer that coats at least a part of a surface of the water-absorbent resin particle, wherein the coating layer is chemically and/or physically bonded to the surface of the water-absorbent resin particle, the coating layer contains a water-soluble component in which a solubility in 100 g of water is in a range of 1.0 g or more and 5 g or less at 25° C., and an organic water-insoluble component with a solubility in 100 g of water of less than 1.0 g at 25° C., the water-absorbent resin particle contains a crosslinking polymer having a monomer unit derived from an ethylenically unsaturated monomer, and the ethylenically unsaturated monomer contains at least one selected from the group consisting of (meth) acrylic acid and a salt thereof, and the degree of neutralization of the acid group in the ethylenically unsaturated monomer is 50 to 90 mol %, the organic water-insoluble component comprises a copolymer of an alkene and a water-soluble ethylenically unsaturated monomer, wherein the alkene is at least one selected from ethylene, propylene, and butene, and the water-soluble component comprises a compound that is at least one selected from the group consisting of polyalkylene oxide, polyalkylene glycol, polyoxyalkylene alkyl ether, and a copolymer of monomers constituting these polymers.

2 . The coated resin particle according to claim 1 , wherein the water-soluble component contains a compound having a hydrophilic group, and the compound has at least one group selected from the group consisting of an anionic group, a cationic group, an amphoteric group, and a nonionic group.

3 . The coated resin particle according to claim 1 , wherein the water-soluble component contains a compound having a hydrophilic group, and the compound has at least one group selected from the group consisting of a hydroxyl group and a (poly) oxyalkylene group.

4 . The coated resin particle according to claim 1 , wherein a water absorption amount of the water-absorbent resin particle is 10 to 100 g/g at 25° C.

5 . The coated resin particle according to claim 1 , wherein the coating layer includes a coating material, and the resin particle is formed by applying the coating material to the water-absorbent resin particle.

6 . The coated resin particle according to claim 5 , wherein the coating material is applied in a solid form.

7 . The coated resin particle according to claim 6 , wherein the coating material is applied in a liquid form.

8 . The coated resin particle according to claim 1 , wherein a water absorption rate of physiological saline of the coated resin particle at 25° C. after 1 minute is 1.7 cm or less.

9 . A method for producing the coated resin particle according to claim 1 , the method comprising mixing a water-absorbent resin particle, and a coating material containing a water-soluble component in which a solubility in 100 g of water is in the range of 1.0 or more and 5 g or less at 25° C. and an organic water-insoluble component with a solubility in 100 g of water of less than 1.0 g at 25° C. to form a coating layer on at least a part of a surface of the water-absorbent resin particle.

Assignees

• Sumitomo Seika Chemicals

Inventors

• SAWAKI Hiroki
• ONITA Chiho

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