Photoalignment agent and liquid crystal display device including the same

Patent metadata

Field	Value
Publication number	US-11029568-B2
Application number	US-201815863281-A
Country	US
Kind code	B2
Filing date	Jan 5, 2018
Priority date	Feb 21, 2014
Publication date	Jun 8, 2021
Grant date	Jun 8, 2021

Abstract

A photoalignment agent is provided. The photoalignment agent includes a copolymer of ii) at least one of a cyclobutanedianhydride (CBDA) and a cyclobutanedianhydride (CBDA) derivative, and ii) a diamine, and the diamine includes an electron donor group.

First claim

What is claimed is:

1. A liquid crystal display comprising:
a first substrate;
a thin film transistor disposed on the first substrate;
a first electrode connected to the thin film transistor; and
a first alignment layer disposed on the first electrode,
wherein the first alignment layer comprises a copolymer of cyclobutanedianhydride, a cyclobutanedianhydride derivative, a first diamine, and a second diamine,
wherein a residual structure of the first diamine in the copolymer includes a group to donate an unshared pair of electrons and a residual structure of the second diamine in the copolymer does not include a group to donate an unshared pair of electrons,
wherein a repeating unit of the copolymer is a compound represented by Formula O:

wherein X1, X2, X3 and X4 are independently hydrogen, fluorine, or an organic compound; at least one among X1, X2, X3 and X4 is not hydrogen; and R1 and R2 are independently hydrogen or an alkyl group; and the organic compound is an alkyl group having a carbon number of 1 to 6.

2. The liquid crystal display of claim 1 , wherein
the first diamine is present in an amount of about 10% to about 30% based on the total weight of the first diamine and the second diamine.

3. The liquid crystal display of claim 1 , further comprising
a second electrode disposed on the first substrate,
an insulating layer disposed between the first electrode and the second electrode, wherein the first electrode includes a plurality of branch electrodes, and the second electrode has a planar shape.

4. The liquid crystal display of claim 3 , wherein
the plurality of branch electrodes overlap the second electrode having the planar shape.

5. The liquid crystal display of claim 4 , further comprising
a passivation layer disposed between the thin film transistor and the second electrode, wherein the thin film transistor and the first electrode are connected by a contact hole defined in the passivation layer and the insulating layer.

6. The liquid crystal display of claim 1 , further comprising:
a second substrate facing the first substrate;
a second alignment layer disposed on the second substrate; and
a liquid crystal layer disposed between the first substrate and the second substrate, wherein the liquid crystal layer comprises liquid crystal molecules,
wherein the second alignment layer comprises a same material as the first alignment layer.

Assignees

• Samsung Display Co Ltd

Inventors

• Kang Suk Hoon
• Park Yeong Rong
• Lee Mi Hwa
• Lee Jun Woo
• Jeon Baek Kyun

Classifications

• C08G73/1042

  Copolyimides derived from at least two different tetracarboxylic compounds or two different diamino compounds · CPC title

• C09D179/08

  Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors · CPC title

• C09K2323/027

  Polyimide · CPC title

• G02F1/133723 Primary

  Polyimide, polyamide-imide · CPC title

• C08G73/1078 Primary

  wholly aromatic in the diamino moiety · CPC title