Polyester adhesive composition

Patent metadata

Field	Value
Publication number	US-9260639-B2
Application number	US-201013519386-A
Country	US
Kind code	B2
Filing date	Dec 27, 2010
Priority date	Dec 28, 2009
Publication date	Feb 16, 2016
Grant date	Feb 16, 2016

Abstract

The present invention has an object to provide a solvent-free polyester-based adhesive composition having good coatability and capable of forming an adhesive that shows good adhesion performance. The present invention provides a polyester-based adhesive composition containing a polyester having Mw of from 1×10 3 to 20×10 3 as a main component and a trifunctional or more polyepoxy compound as a crosslinking agent, and containing substantially no organic solvent. The molar number, m OH , of hydroxyl group contained in a polyalcohol component constituting the polyester is from 0.5 to 0.98 times of the molar number, m COOH , of carboxyl group contained in a polycarboxylic acid component. The composition has a viscosity at 23° C. of at most 80 Pa·s.

First claim

The invention claimed is:

1. An adhesive composition containing substantially no organic solvent,
wherein the composition is a polyester-based adhesive composition comprising a polyester having a weight-average molecular weight of from 1.0×10 3 to 20×10 3 as a main component thereof and a trifunctional or more polyepoxy compound as a crosslinking agent,
wherein, when the molar number, m cooH , of carboxyl group contained in a polycarboxylic acid component constituting the polyester is taken as 1, the molar number, m OH , of hydroxyl group contained in a polyalcohol component constituting the polyester is from 0.5 to 0.98,
wherein the composition has a viscosity at 23° C. of at most 80 Pa·s, and
wherein at least one polycarboxylic acid of the polycarboxylic acid component constituting the polyester is an aliphatic dicarboxylic acid having a dimerized structure of an unsaturated fatty acid.

2. The adhesive composition according to claim 1 , wherein the adhesive formed by crosslinking the adhesive composition has a glass transition temperature of from −70° C. to −20° C.

3. The adhesive composition according to claim 1 , wherein the adhesive formed by crosslinking the adhesive composition has a gel fraction of from 30% to 95%.

4. The adhesive composition according to claim 1 , wherein at least one polyalcohol of the polyalcohol component constituting the polyester is an aliphatic diol having a structure where an aliphatic dicarboxylic acid of a dimerized unsaturated fatty acid is subjected to hydrogenation.

5. The adhesive composition according to claim 1 , wherein the polyester is a polycondensate of a dimer acid with a dimer diol.

6. A pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer formed by crosslinking the adhesive composition according to claim 1 , on a substrate.

Assignees

• Takahira Hitoshi
• Yoshie Satomi
• Tanimura Miki
• Nitto Denko Corp

Inventors

• Takahira Hitoshi
• Yoshie Satomi
• Tanimura Miki

Classifications

• C09J167/00

  Adhesives based on polyesters obtained by reactions forming a carboxylic ester link in the main chain (based on polyester-amides C09J177/12; based on polyester-imides C09J179/08); Adhesives based on derivatives of such polymers · CPC title

• C08K5/0025

  Crosslinking or vulcanising agents; including accelerators · CPC title

• Y10T428/31794

  Of cross-linked polyester · CPC title

• B32B2255/26

  Polymeric coating · CPC title

• Y10T428/287

  including epoxy group or epoxy polymer · CPC title