Composition for forming thermoset film having photo alignment properties

Patent metadata

Field	Value
Publication number	US-9796843-B2
Application number	US-201013381836-A
Country	US
Kind code	B2
Filing date	Jul 20, 2010
Priority date	Jul 21, 2009
Publication date	Oct 24, 2017
Grant date	Oct 24, 2017

Abstract

A material from which a cured film exhibiting high solvent resistance, liquid crystal-alignment performance, heat resistance and high transparency can be formed. A composition for forming a thermoset film having photo alignment properties, the composition comprising: a component (A) that is an acrylic copolymer having a photodimerizing moiety and a thermal cross-linking moiety; a component (B) that is an acrylic polymer having at least one of a C 2-5 alkyl ester group and a C 2-5 hydroxyalkyl ester group and at least one of a carboxy group and a phenolic hydroxy group; and a component (C) that is a cross-linking agent.

First claim

The invention claimed is:

1. A composition for forming a thermoset film having photo alignment properties, the composition comprising:
a component (A) that is an acrylic copolymer having a photodimerizing moiety and a thermal cross-linking moiety, wherein the photodimerizing moiety includes a structure selected from the group consisting of a cinnamoyl group, a chalcone group, a coumarin group, and an anthracene group, and the thermal cross-linking moiety includes a structure selected from the group consisting of a hydroxy group, a carboxy group, and a glycidyl group;
a component (B) that is an acrylic polymer synthesized by copolymerization of monomers consisting of 2 to 95 mol % of at least one monomer selected from monomer b1 and 5 to 98 mol % of at least one monomer selected from monomer b2:
monomer b1: methyl methacrylate, methyl acrylate, ethyl methacrylate, ethyl acrylate, propyl methacrylate, propyl acrylate, isopropyl methacrylate, isopropyl acrylate, butyl methacrylate, butyl acrylate, isobutyl methacrylate, isobutyl acrylate, t-butyl methacrylate, t-butyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl methacrylate, and 2-hydroxypropyl acrylate;
monomer b2: acrylic acid, methacrylic acid, vinylbenzoic acid, p-hydroxystyrene, m-hydroxystyrene, and o-hydroxystyrene; and
a component (C) that is a cross-linking agent that is bonded to the thermal cross-linking moiety in the acrylic copolymer as the component (A) and a carboxy group moiety and/or a phenolic hydroxyl group moiety included in the component (B), wherein the cross-linking agent is selected from the group consisting of an epoxy compound, a methylol compound, and an isocyanate compound,
wherein the composition is curable by heating to form said thermoset film having photo-alignment properties, and
the composition exhibits photo alignment properties after exposure to perpendicular irradiation with linear polarization at 313 nm of 10 to 20 mJ/cm 2 .

2. The composition for forming a thermoset film having photo alignment properties according to claim 1 , wherein the component (A) is an acrylic copolymer obtained by a polymerization reaction of monomers including a monomer having the photodimerizing moiety and a monomer having the thermal cross-linking moiety.

3. The composition for forming a thermoset film having photo alignment properties according to claim 1 , wherein the photodimerizing moiety in the component (A) is a cinnamoyl group.

4. The composition for forming a thermoset film having photo alignment properties according to claim 1 , wherein the thermal cross-linking moiety in the component (A) is a hydroxy group.

5. The composition for forming a thermoset film having photo alignment properties according to claim 1 , wherein the cross-linking agent in the component (C) is a cross-linking agent having a methylol group or an alkoxymethylol group.

6. The composition for forming a thermoset film having photo alignment properties according to claim 1 , further comprising a component (D) that is an acid or a thermal acid generator.

7. The composition for forming a thermoset film having photo alignment properties according to claim 1 , further comprising a component (E) that is a sensitizer.

8. The composition for forming a thermoset film having photo alignment properties according to claim 1 , wherein the composition contains the component (C) in an amount of 1 to 40 part(s) by mass based on 100 parts by mass of a total amount of the component (A) and the component (B).

9. The composition for forming a thermoset film having photo alignment properties according to claim 6 , wherein the composition contains the component (D) in an amount of 0.01 to 5 parts by mass based on 100 parts by mass of a total amount of the component (A) and the component (B).

10. The composition for forming a thermoset film having photo alignment properties according to claim 7 , wherein the composition contains the component (E) in an amount of 0.1 to 20 parts by mass based on 100 parts by mass of a total amount of the component (A) and the component (B).

11. A liquid crystal alignment layer formed from the composition for forming a thermoset film having photo alignment properties as claimed in claim 1 .

12. An optical device comprising:
a liquid crystal alignment layer formed from the composition for forming a thermoset film having photo alignment properties as claimed in claim 1 ; and
a retardation layer on the liquid crystal alignment layer.

Assignees

• Hatanaka Tadashi
• Adachi Isao
• Nissan Chemical Ind Ltd

Inventors

• Hatanaka Tadashi
• Adachi Isao

Classifications

• C08F220/14

  Methyl esters {, e.g. methyl (meth)acrylate} · CPC title

• C09D133/14

  of esters containing halogen, nitrogen, sulfur or oxygen atoms in addition to the carboxy oxygen · CPC title

• C08K5/0025

  Crosslinking or vulcanising agents; including accelerators · CPC title

• C08L33/08

  Homopolymers or copolymers of acrylic acid esters · CPC title

• C08F220/303

  and one or more carboxylic moieties in the chain · CPC title