Liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display device

Patent metadata

Field	Value
Publication number	US-9505981-B2
Application number	US-201514660898-A
Country	US
Kind code	B2
Filing date	Mar 17, 2015
Priority date	Mar 25, 2014
Publication date	Nov 29, 2016
Grant date	Nov 29, 2016

Abstract

A liquid crystal alignment agent, a liquid crystal alignment film, and a liquid crystal display device are provided. The liquid crystal alignment agent includes a polymer composition (A-1) and a solvent (B). The polymer composition (A-1) is obtained by reacting a tetracarboxylic acid dianhydride compound (a) with a diamine compound (b). The diamine compound (b) includes at least one type of diamine (b-1) represented by formula (I) and at least one type of diamine (b-2) having the structure represented by formula (II). The liquid crystal alignment agent can be made into a liquid crystal display device having good uniformity of pretilt angle after ultraviolet irradiation.

First claim

What is claimed is:

1. A liquid crystal alignment agent, comprising:
a polymer composition (A-1); and
a solvent (B),
wherein the polymer composition (A-1) is obtained by reacting a tetracarboxylic acid dianhydride compound (a) with a diamine compound (b),
the diamine compound (b) comprises at least one type of a diamine (b-1) represented by formula (I) and at least one type of a diamine (b-2) having a structure represented by formula (II), wherein a molar ratio (b-1)/(b-2) of the diamine (b-1) represented by formula (I) and the diamine (b-2) having the structure represented by formula (II) is 0.05 to 1.5,

in formula (I), R 1 and R 3 each independently represent an ether group, a thioether group, an ester group, or a thioester group;
R 2 represents an alkylene group containing an unsaturated bond;
R 4 represents a single bond, a methylene group, or an ethylene group;
A represents a C 17 to C 40 monovalent organic group having a steroid frame,

in formula (II), R 5 and R 6 each independently represent a C 1 to C 6 alkyl group, a C 1 to C 6 alkoxy group, a halogen atom, or a cyano group;
a and b each independently represent an integer of 0 to 4;
c represents 0 or 1;
* each independently represents a bonding position.

2. The liquid crystal alignment agent of claim 1 , wherein the diamine (b-2) having the structure represented by formula (II) comprises a structure represented by formula (II-1), a structure represented by formula (II-2), or a combination of the two,

in formula (II-1) and formula (II-2),
R 8 , R 9 , R 11 , and R 12 each independently represent a C 1 to C 6 alkyl group, a C 1 to C 6 alkoxy group, a halogen atom, or a cyano group;
R 10 and R 13 each independently represent a C 1 to C 40 alkyl group or a C 1 to C 40 alkyl group substituted by a fluorine atom;
Y 1 , Y 2 , and Y 3 each independently represent

wherein R 14 represents a hydrogen atom or a C 1 to C 4 alkyl group;
Z 1 and Z 2 each independently represent a methylene group, an arylene group, a divalent alicyclic group, —Si(CH 3 ) 2 —, —CH═CH—, —C≡C—, a methylene group having a substituent, an arylene group having a substituent, a divalent alicyclic group having a substituent, —Si(CH 3 ) 2 -having a substituent, or —CH═CH— having a substituent, wherein the substituent is a cyano group, a halogen atom, or a C 1 to C 4 alkyl group;
d, e, j, and k each independently represent an integer of 0 to 4;
f and m represent 0 or 1;
g and n each independently represent an integer of 1 to 6;
h and p each independently represent an integer of 0 to 2;
i represents an integer of 0 or 1;
* each independently represents a bonding position.

3. The liquid crystal alignment agent of claim 1 , wherein based on a total number of moles of 100 moles of the diamine compound (b), a usage amount of the diamine (b-1) represented by formula (I) is 0.5 to 50 moles, and a usage amount of the diamine (b-2) having the structure represented by formula (II) is 10 to 80 moles.

4. The liquid crystal alignment agent of claim 1 , wherein a molar ratio (b-1)/(b-2) of the diamine (b-1) represented by formula (I) and the diamine (b-2) having the structure represented by formula (II) is 0.1 to 1.3.

5. The liquid crystal alignment agent of claim 4 , wherein a molar ratio (b-1)/(b-2) of the diamine (b-1) represented by formula (I) and the diamine (b-2) having the structure represented by formula (II) is 0.2 to 1.0.

6. A liquid crystal alignment film formed by the liquid crystal alignment agent of claim 1 .

7. A liquid crystal display device, comprising the liquid crystal alignment film of claim 6 .

Assignees

• Chi Mei Corp

Inventors

• Chiou Shin-Rong

Classifications

• C08G73/1075

  Partially aromatic polyimides · CPC title

• G02F1/133711

  by organic films, e.g. polymeric films · CPC title

• Y02P20/582

  Recycling of unreacted starting or intermediate materials · CPC title

• C09K19/56 Primary

  Aligning agents · CPC title

• G02F1/133723

  Polyimide, polyamide-imide · CPC title