Urethane resin

Patent metadata

Field	Value
Publication number	US-11840598-B2
Application number	US-202017637739-A
Country	US
Kind code	B2
Filing date	Aug 26, 2020
Priority date	Aug 27, 2019
Publication date	Dec 12, 2023
Grant date	Dec 12, 2023

Abstract

There is provided a urethane resin that is excellent in adhesive strength, and maintains high adhesive strength even after exposure to high temperature and humidity. A urethane resin obtained by reacting a glycol-modified aromatic hydrocarbon-formaldehyde resin (A) modified with a glycol with a polyisocyanate (B) having two or more free isocyanate groups in a molecule.

First claim

The invention claimed is:

1. A urethane resin produced by a process comprising:
reacting a glycol-modified aromatic hydrocarbon-formaldehyde resin (A) modified with a glycol with a polyisocyanate (B) having at least two free isocyanate groups in a molecule,
wherein the glycol-modified aromatic hydrocarbon-formaldehyde resin (A) has a hydroxyl value of from 50 to 250 mg KOH/g, and
wherein the glycol is at least one selected from the group consisting of neopentyl glycol, a spiroglycol, ethylene glycol, diethylene glycol, dipropylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 2,5-hexanediol, 1,2-hexanediol, 1,2-octanediol, 1,10-decanediol, 3-hexyne-2,5-diol, 2,5-dimethyl-3-hexyne-2,5-diol, 2,2,4-trimethyl-1,3-pentanediol, polyethylene glycol, and polyoxypropylene glycol.

2. The urethane resin according to claim 1 , wherein the glycol-modified aromatic hydrocarbon-formaldehyde resin (A) is produced by a process comprising reacting 100 parts by mass of an aromatic hydrocarbon-formaldehyde resin with from 10 to 100 parts of the glycol.

3. The urethane resin according to claim 1 , wherein the glycol-modified aromatic hydrocarbon-formaldehyde resin (A) has a weight average molecular weight of from 250 to 5,000 in terms of polystyrene.

4. The urethane resin according to claim 1 , wherein the glycol-modified aromatic hydrocarbon-formaldehyde resin (A) is an ethylene glycol-modified xylene-formaldehyde resin.

5. The urethane resin according to claim 1 , wherein the process comprises reacting the glycol-modified aromatic hydrocarbon-formaldehyde resin (A), the polyisocyanate (B), and further a polyol (C).

6. The urethane resin according to claim 5 , wherein a molar ratio of isocyanate groups (NCO) of the polyisocyanate (B) to a total of hydroxy groups (OH T ) of the glycol-modified aromatic hydrocarbon-formaldehyde resin (A) and the polyol (C) (NCO/OH T ) is from 1.0 to 4.0.

7. The urethane resin according to claim 1 , wherein the polyisocyanate (B) is a polyisocyanate comprising at least one aromatic group.

8. The urethane resin according to claim 1 , wherein the polyisocyanate (B) is an aliphatic polyisocyanate comprising no aromatic group.

9. The urethane resin according to claim 1 , wherein the glycol-modified aromatic hydrocarbon-formaldehyde resin (A) is present at a mass percentage of from 1 to 50% by mass relative to 100% by mass of a total of starting materials of the urethane resin.

10. The urethane resin according to claim 1 , wherein the glycol-modified aromatic hydrocarbon-formaldehyde resin (A) is reacted with the polyisocyanate (B) in a water solvent.

11. An adhesive comprising the urethane resin of claim 1 .

12. A paint comprising the urethane resin of claim 1 .

13. The urethane resin according to claim 2 , wherein the glycol-modified aromatic hydrocarbon-formaldehyde resin (A) has a weight average molecular weight of 250 to 5,000 in terms of polystyrene.

Assignees

• Mitsubishi Gas Chemical Co

Inventors

• Hariu Tomohiro
• Ota Yosuke

Classifications

• C08G18/3209 Primary

  Aliphatic aldehyde condensates and hydrogenation products thereof · CPC title

• C08G18/0847

  in the presence of solvents for the polymers · CPC title

• C08G18/10

  Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step · CPC title

• C08G18/4238

  derived from dicarboxylic acids and dialcohols · CPC title

• C08G2150/00

  Compositions for coatings · CPC title