Adhesive composition for optical use and adhesive layer for optical use comprising cured product thereof

Patent metadata

Field	Value
Publication number	US-10647894-B2
Application number	US-201716094663-A
Country	US
Kind code	B2
Filing date	Apr 4, 2017
Priority date	Apr 22, 2016
Publication date	May 12, 2020
Grant date	May 12, 2020

Abstract

Provided is an adhesive composition for an optical use, including: a first isobutylene-isoprene-based rubber having a weight average molecular weight (Mw) of 100,000 g/mol to 1,000,000 g/mol; and a second isobutylene-isoprene-based rubber having a weight average molecular weight (Mw) of 5,000 g/mol to 100,000 g/mol, in which the first isobutylene-isoprene-based rubber and the second isobutylene-isoprene-based rubber each include a hydroxy group. Further, provided is an adhesive layer including a thermally cured product of the adhesive composition for optical use.

First claim

The invention claimed is:

1. An adhesive composition for optical use, comprising:
a first isobutylene-isoprene-based rubber having a weight average molecular weight (Mw) of 100,000 g/mol to 1,000,000 g/mol; and
a second isobutylene-isoprene-based rubber having a weight average molecular weight (Mw) of 5,000 g/mol to 100,000 g/mol,
wherein each of the first isobutylene-isoprene-based rubber and the second isobutylene-isoprene-based rubber comprise a hydroxy group.

2. The adhesive composition of claim 1 , wherein an isoprene unit of each of the first isobutylene-isoprene-based rubber and the second isobutylene-isoprene-based rubber includes the hydroxy group.

3. The adhesive composition of claim 1 , wherein each of the first isobutylene-isoprene-based rubber and the second isobutylene-isoprene-based rubber do not contain an acid group.

4. The adhesive composition of claim 1 , wherein a molar amount of an isoprene unit in the first isobutylene-isoprene rubber is 1 mol % or more and 30 mol % or less based on a total molar amount of an isobutylene unit and the isoprene unit in the first isobutylene-isoprene rubber.

5. The adhesive composition of claim 1 , wherein the first isobutylene-isoprene-based rubber has a hydroxyl value (OH value) of 0.5 mgKOH/g to 10 mgKOH/g.

6. The adhesive composition of claim 1 , wherein a molar amount of an isoprene unit of in the second isobutylene-isoprene rubber is 1 mol % or more and 30 mol % or less based on a total mole number molar amount of an isobutylene unit and an isoprene unit in the second isobutylene-isoprene rubber.

7. The adhesive composition of claim 1 , wherein the second isobutylene-isoprene-based rubber has a hydroxyl value (OH value) of 0.5 mgKOH/g to 20 mgKOH/g.

8. The adhesive composition of claim 1 , wherein a weight ratio of the first isobutylene-isoprene-based rubber and to the second isobutylene-isoprene-based rubber is 2:8 to 8:2.

9. The adhesive composition of claim 1 , further comprising:
one or more additives selected from the group consisting of a curing agent, a reaction accelerator, a curing retarder, and an adhesion promoter.

10. An adhesive layer for optical use, comprising:
a cured product of the adhesive composition for of claim 1 .

11. The adhesive layer of claim 10 , wherein the adhesive layer for optical use has a glass transition temperature (Tg) of −70° C. to −40° C.

12. The adhesive layer of claim 10 , wherein the adhesive layer for optical use has a storage modulus of 1.0 MPa to 5.0 MPa at −40° C., a storage modulus of 0.05 MPa to 0.20 MPa at 25° C., and a storage modulus of 0.01 MPa to 0.10 MPa at 60° C.

13. The adhesive composition of claim 1 , wherein the first isobutylene-isoprene-based rubber has a Mw of 500,000 g/mol to 1,000,000 g/mol.

14. The adhesive composition of claim 1 , wherein the second isobutylene-isoprene-based rubber has a Mw of 5,000 g/mol to 70,000 g/mol.

15. The adhesive composition of claim 1 , wherein a molar amount of isoprene units in the second isobutylene-isoprene-based rubber is greater than a molar amount of isoprene units in the first isobutylene-isoprene-based rubber.

Assignees

• Lg Chemical Ltd

Inventors

• Seo Kwang Su
• Park Eun Kyung
• Lee Seung Won
• Kim Jang Soon
• Choi Tae Yi

Classifications

• C09J115/00 Primary

  Adhesives based on rubber derivatives (C09J111/00, C09J113/00 take precedence) · CPC title

• C09J7/20

  characterised by their carriers · CPC title

• G06F3/041

  Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means · CPC title

• C09J119/006 Primary

  Rubber characterised by functional groups, e.g. telechelic diene polymers · CPC title

• C09J2203/326

  for bonding electronic components such as wafers, chips or semiconductors · CPC title