Pressure-sensitive adhesive composition and pressure-sensitive adhesive sheet

Patent metadata

Field	Value
Publication number	US-9683134-B2
Application number	US-201314385210-A
Country	US
Kind code	B2
Filing date	Mar 7, 2013
Priority date	Mar 16, 2012
Publication date	Jun 20, 2017
Grant date	Jun 20, 2017

Abstract

A polyester-based pressure-sensitive adhesive composition comprises a polyester obtained by condensation polymerization of at least a dicarboxylic acid having a side chain and a diol, a polyether polyol, and a crosslinking agent, wherein the polyester has a weight average molecular weight of 5000 to 50000, the polyether polyol contains a polyether polyol having hydroxyl groups at only part of terminals and/or all terminals, the polyether polyol having hydroxyl groups at only part of terminals has a number average molecular weight of 100 to 1500, and the polyether polyol having hydroxyl groups at only part of terminals is contained in an amount of 1 to 35 parts by weight based on 100 parts by weight of the polyester.

First claim

The invention claimed is:

1. A polyester-based pressure-sensitive adhesive composition comprising a polyester, a polyether polyol, and a crosslinking agent, wherein
the polyester is obtained by condensation polymerization of at least a dicarboxylic acid having a side chain and a diol, and the polyester does not contain a lactic acid unit,
the polyester has a weight average molecular weight of 5000 to 50000,
the polyether polyol contains a polyether polyol having hydroxyl groups at only part of the terminals and/or all terminals,
the polyether polyol having hydroxyl groups at only part of the terminals has a number average molecular weight of 100 to 1500, and
the polyether polyol having hydroxyl groups at only part of the terminals is contained in an amount of 1 to 35 parts by weight based on 100 parts by weight of the polyester.

2. The polyester-based pressure-sensitive adhesive composition according to claim 1 , wherein the polyether polyol having hydroxyl groups at all terminals has a number average molecular weight of 100 to 5000, and the polyether polyol having hydroxyl groups at all terminals is contained in an amount of 1 to 400 parts by weight based on 100 parts by weight of the polyester.

3. The polyester-based pressure-sensitive adhesive composition according to claim 1 , wherein the dicarboxylic acid and the diol are present in a mole ratio of 1:(1.08 to 2.10).

4. The polyester-based pressure-sensitive adhesive composition according to claim 1 , wherein the side chain of the dicarboxylic acid is an alkyl group.

5. A pressure-sensitive adhesive sheet comprising a support and a pressure-sensitive adhesive layer obtained by crosslinking the polyester-based pressure-sensitive adhesive composition according to claim 1 and formed on at least one surface of the support.

6. The pressure-sensitive adhesive sheet according to claim 5 , wherein the pressure-sensitive adhesive layer has a gel fraction of 40 to 95% by weight.

7. The pressure-sensitive adhesive sheet according to claim 5 , which has an adhesive strength to glass of 1.0 N/25 mm or less.

8. The pressure-sensitive adhesive sheet according to claim 5 , which is used for surface protection.

Assignees

• Nitto Denko Corp

Inventors

• Ishiguro Shigeki
• Yoshie Satomi
• Senda Hiroki

Classifications

• C08L71/02 Primary

  Polyalkylene oxides · CPC title

• C09J167/08

  Polyesters modified with higher fatty oils or their acids, or with natural resins or resin acids · CPC title

• C09J167/02 Primary

  Polyesters derived from dicarboxylic acids and dihydroxy compounds (C09J167/06 takes precedence) · CPC title

• C08G63/553

  Acids or hydroxy compounds containing cycloaliphatic rings, e.g. Diels-Alder adducts · CPC title

• Y10T428/2852

  Adhesive compositions · CPC title