Pressure-sensitive adhesive composition, pressure-sensitive adhesive layer, pressure-sensitive adhesive tape, and double-coated pressure-sensitive adhesive tape

Patent metadata

Field	Value
Publication number	US-10087345-B2
Application number	US-201415103574-A
Country	US
Kind code	B2
Filing date	Dec 17, 2014
Priority date	Dec 20, 2013
Publication date	Oct 2, 2018
Grant date	Oct 2, 2018

Abstract

A polyester-based pressure-sensitive adhesive layer, pressure-sensitive adhesive tape, and double-coated pressure-sensitive adhesive tape each having high durability (high heating humidification storage stability) and good adhesive properties are provided using a polyester-based pressure-sensitive adhesive composition. The polyester-based pressure-sensitive adhesive composition of the invention includes a polyester, a hydrolysis-resistant agent, a tackifier with an acid value of 8 or less and a softening point of 80 to 170° C., and a crosslinking agent, and contains 20 to 100 parts by weight of the tackifier based on 100 parts by weight of the polyester.

First claim

The invention claimed is:

1. A polyester-based pressure-sensitive adhesive layer comprising a polyester-based pressure-sensitive adhesive composition comprising a polyester, a hydrolysis-resistant agent, a tackifier, and a crosslinking agent, wherein
the tackifier has an acid value of 8 or less,
the tackifier has a softening point of 80 to 170° C.,
the polyester-based pressure-sensitive adhesive composition containing 20 to 40 parts by weight of the tackifier based on 100 parts by weight of the polyester,
the polyester has a weight average molecular weight of 15,000 to 60,000,
the polyester-based pressure-sensitive adhesive layer has a holding power of 0.8 mm/60 minutes or less at 40° C., and
the polyester-based pressure-sensitive adhesive composition contains 0.05 to 2 parts by weight of the hydrolysis-resistant agent based on 100 parts of the polyester.

2. The polyester-based pressure-sensitive adhesive layer according to claim 1 , wherein the hydrolysis-resistant agent is a carbodiimide group-containing compound.

3. The polyester-based pressure-sensitive adhesive layer according to claim 1 , wherein the polyester is a product obtained by polycondensation of at least a dicarboxylic acid component and a diol component.

4. The polyester-based pressure-sensitive adhesive layer according to claim 1 , wherein the tackifier comprises at least one terpene resin.

5. The polyester-based pressure-sensitive adhesive layer according to claim 1 , wherein
the polyester-based pressure-sensitive adhesive layer has an adhesive strength of 7 N/20 mm or more to a polycarbonate plate.

6. The polyester-based pressure-sensitive adhesive layer according to claim 5 , which is provided with a release liner on at least one side of the layer.

7. The polyester-based pressure-sensitive adhesive layer according to claim 1 , wherein all of the polyester in said polyester-based pressure-sensitive adhesive composition possesses a weight average molecular weight of 15,000 to 60,000.

8. A polyester-based pressure-sensitive adhesive tape comprising the polyester-based pressure-sensitive adhesive layer according to claim 5 and a support provided on at least one side of the layer.

9. A polyester-based double-coated pressure-sensitive adhesive tape, comprising:
at least two polyester-based pressure-sensitive adhesive layers according to claim 5 ; and
a support provided between the two polyester-based pressure-sensitive adhesive layers.

Assignees

• Nitto Denko Corp

Inventors

• Yoshida Akiko
• Ishiguro Shigeki
• Yoshie Satomi

Classifications

• C09J2467/00

  Presence of polyester · CPC title

• C09J193/04

  Rosin · CPC title

• C09J193/00

  Adhesives based on natural resins; Adhesives based on derivatives thereof · CPC title

• C09J167/08

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

• C09J167/02

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