Optically clear adhesives for durable plastic bonding

Patent metadata

Field	Value
Publication number	US-10214666-B2
Application number	US-201415038863-A
Country	US
Kind code	B2
Filing date	Dec 3, 2014
Priority date	Dec 4, 2013
Publication date	Feb 26, 2019
Grant date	Feb 26, 2019

Abstract

The present invention is a copolymer of a monomer mixture including about 25 to about 80 parts by mass of an alkyl (meth)acrylate, approximately 15 to approximately 50 parts by mass of a hydroxyl group-containing monomer, and approximately 5 to approximately 25 parts by mass of a macromer having a glass transition temperature (Tg) of approximately 50° C. or higher. The copolymer contains substantially no acidic groups.

First claim

What is claimed is:

1. An optically clear adhesive comprising:
a copolymer of a monomer mixture comprising:
25 to 80 parts by mass of an alkyl (meth)acrylate;
15 to 50 parts by mass of a hydroxyl group-containing monomer;
5 to 25 parts by mass of a macromer having a glass transition temperature (Tg) of 50° C. or higher, wherein the monomers that constitute the main chain of the macromer includes methacrylate monomers, styrene-based monomers or acrylonitrile, and wherein the number molecular weight of the macromer in Dalton is 2000 or higher and 50000 or lower; and
a crosslinkable monomer comprising difunctional (meth)acrylates or polyfunctional (meth)acrylates, wherein when the total quantity of the alkyl (meth)acrylate, the hydroxyl group-containing monomer, and the macromer is 100 parts by mass, the crosslinkable monomer is at a quantity of 0.01 parts by mass or higher and 5 parts by mass or lower,

wherein the copolymer contains substantially no acidic groups, wherein the acid value of the copolymer that contains substantially no acidic groups is 5 mg KOH/g or lower.

2. The optically clear adhesive according to claim 1 , wherein the copolymer comprises substantially no nitrogen-containing sites, wherein the nitrogen content of the copolymer that contains substantially no nitrogen-containing sites is 1 mass % or lower.

3. The optically clear adhesive according to claim 1 , wherein a main chain of the macromer has methyl methacrylate units.

4. The optically clear adhesive according to claim 1 , wherein the optically clear adhesive further comprises a silane coupling agent.

5. The optically clear adhesive according to claim 1 , wherein the alkyl (meth)acrylate comprises n-butyl acrylate.

6. An optical laminate comprising:
a first base material having a major surface;
a second base material having a major surface; and
the optically clear adhesive described in claim 1 disposed between the major surface of the first base material and the major surface of the second base material so as to be in contact with the major surface of the first base material and the major surface of the second base material.

Assignees

• 3M Innovative Properties Co

Inventors

• Nakada Aya
• Hatanaka Hideyuki
• Yoda Masaki
• Suwa Toshihiro
• Everaerts Albert I
• Suzuki Shunsuke
• Kinoshita Yasuhiro

Classifications

• C09J133/066 Primary

  containing -OH groups · CPC title

• C08F290/046

  Polymers of unsaturated carboxylic acids or derivatives thereof · CPC title

• B32B7/12

  using interposed adhesives or interposed materials with bonding properties · CPC title

• B32B2457/20

  Displays, e.g. liquid crystal displays, plasma displays · CPC title

• C09J155/005

  Homopolymers or copolymers obtained by polymerisation of macromolecular compounds terminated by a carbon-to-carbon double bond · CPC title