Water-soluble resin for printing

Patent metadata

Field	Value
Publication number	US-12359076-B2
Application number	US-202017605610-A
Country	US
Kind code	B2
Filing date	Apr 24, 2020
Priority date	Apr 26, 2019
Publication date	Jul 15, 2025
Grant date	Jul 15, 2025

Abstract

The water-soluble resin for printing of the present invention includes a monomer unit A having a sulfonate group; and a monomer unit B having no hydrophilic group, and a percentage of the monomer unit A based on a total of all monomer units is 5 to 35 mol %. According to the water-soluble resin for printing of the present invention, a printed matter from which a printing layer can be safely and efficiently removed with neutral water and which is excellent in water resistance can be realized.

First claim

The invention claimed is:

1. A method for removing a printing layer, the method comprising:
treating a printed matter comprising a water-soluble printing layer with neutral water at 30° C. or more to remove the water-soluble printing layer,
wherein the water-soluble printing layer comprises a water-soluble resin for printing comprising:
a monomer unit A having a sulfonate group; and
a monomer unit B derived from a monomer having no hydrophilic groups other than groups that constitute polymerization in producing the water-soluble resin,

wherein a percentage of the monomer unit A based on a total of all monomer units is 5 to 35 mol %.

2. A method for removing a printing layer, the method comprising:
treating a printed matter with neutral water at 30° C. or more to remove a water-soluble printing primer layer and the printing layer,
wherein the printed matter comprises, in sequence:
a substrate;
the water-soluble printing primer layer containing a water-soluble resin for printing; and
the printing layer, and

wherein the water-soluble resin comprises:
a monomer unit A having a sulfonate group; and
a monomer unit B derived from a monomer having no hydrophilic groups other than groups that constitute polymerization in producing the water-soluble resin,

wherein a percentage of the monomer unit A based on a total of all monomer units is 5 to 35 mol %.

3. The method according to claim 1 , wherein a counterion of a sulfonic acid group that constitutes the sulfonate group in the monomer unit A is an alkali metal ion.

4. The method according to claim 1 , wherein a content of the sulfonate group in the water-soluble resin is 0.4 to 3 mmol/g.

5. The method according to claim 1 , wherein a weight average molecular weight of the water-soluble resin is 1000 to 80000.

6. The method according to claim 1 , wherein
the monomer unit A is a dicarboxylic acid-derived monomer unit A, and
the monomer unit B is a dicarboxylic acid-derived monomer unit B, which is derived from a dicarboxylic acid having no other hydrophilic group.

7. The method according to claim 6 , wherein a monomer from which the dicarboxylic acid-derived monomer unit A is derived is at least one sulfonate group-containing aromatic dicarboxylic acid salt.

8. The method according to claim 6 , wherein a monomer from which the dicarboxylic acid-derived monomer unit A is derived is 5-sulfoisophthalic acid.

9. The method according to claim 6 , wherein the dicarboxylic acid from which the dicarboxylic acid-derived monomer unit B is derived is at least one selected from the group consisting of an aromatic dicarboxylic acid having no other hydrophilic group and an aliphatic dicarboxylic acid having no other hydrophilic group.

10. The method according to claim 9 , wherein the dicarboxylic acid from which the dicarboxylic acid-derived monomer unit B is derived is at least one aromatic dicarboxylic acid having no other hydrophilic group selected from the group consisting of terephthalic acid, isophthalic acid, 2,5-furandicarboxylic acid, and 2,6-naphthalenedicarboxylic acid.

11. The method according to claim 9 , wherein the dicarboxylic acid from which the dicarboxylic acid-derived monomer unit B is derived is at least one aliphatic dicarboxylic acid having no other hydrophilic group selected from the group consisting of malonic acid, succinic acid, glutaric acid, adipic acid, 1,4-cyclohexanedicarboxylic acid, and 1,3-adamantanedicarboxylic acid.

12. The method according to claim 9 , wherein a percentage of a total of an aromatic dicarboxylic acid based on a total of the dicarboxylic acid from which the dicarboxylic acid-derived monomer unit B is derived is 50 mol % or more and 100 mol % or less.

13. The method according to claim 6 , wherein the water-soluble resin is a water-soluble polyester resin that includes a diol monomer unit C, which is derived from a diol C that has a carbon number of 2 to 31.

14. The method according to claim 13 , wherein the diol C is an aliphatic diol.

15. The method according to claim 14 , wherein the aliphatic diol is at least one selected from the group consisting of a chain diol and a cyclic diol.

16. The method according to claim 15 , wherein the aliphatic diol is at least one chain diol selected from the group consisting of ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,2-butanediol, 1,3-butanediol, neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, diethylene glycol, triethylene glycol, polyethylene glycol, dipropylene glycol, and polypyrene glycol.

17. The method according to claim 15 , wherein the aliphatic diol is at least one cyclic diol selected from the group consisting of 1,4-cyclohexanedimethanol, hydrogenated bisphenol A, isosorbide, bisphenoxyethanolfluorene, bisphenol fluorene, biscresoxyethanolfluorene, and biscresol fluorene.

18. The method according to claim 1 , wherein the water-soluble resin is contained in a water-soluble resin composition in a content of 30% by mass or more and 100% by mass or less.

Assignees

• Kao Corp

Inventors

• Shibutani Ryo
• Katayanagi Gota
• Yoshimura Tadanori
• Onoue Akihiro
• Noro Takahiro
• Sasaki Keiji

Classifications

• C09D181/08

  Polysulfonates · CPC title

• B41M5/0064

  on plastics, horn, rubber, or other organic polymers · CPC title

• B41M5/0047

  by ink-jet printing · CPC title

• B41M7/0009

  Obliterating the printed matter; Non-destructive removal of the ink pattern, e.g. for repetitive use of the support · CPC title

• B41M5/5254

  characterised by the use of polymers obtained by reactions only involving carbon-to-carbon unsaturated bonds, e.g. vinyl polymers · CPC title