Liquid crystal alignment agent composition, method for preparing liquid crystal alignment film using same, and liquid crystal alignment film and liquid crystal display using same

• US 11,149,204 B2
• Filed: 04/17/2019
• Issued: 10/19/2021
• Est. Priority Date: 05/17/2018
• Status: Active Grant

• Current Assignee: LG Chem Limited (LG Corporation)
• Original Assignee: LG Chem Limited (LG Corporation)
• Inventors: Kim, Seongku, Jo, Jung Ho, Park, Hoonseo, Han, Hee, Yoon, Jun Young
• Primary Examiner(s): Ahvazi, Bijan
• Application Number:
  US16/628,906
• Publication Number:
  US 20200190405A1
• Time in Patent Office: 916 Days
• CPC Class Codes: C08G 73/1017 in the form of (mono)amine
• CPC Class Codes: C08G 73/1032 characterised by the solvent(s) used
• CPC Class Codes: C08G 73/1067 Wholly aromatic polyimides, i.e. having both tetracarboxylic and diamino moieties aromatically bound
• CPC Class Codes: C09K 19/56 Aligning agents
• CPC Class Codes: C09K 2323/027 Polyimide
• CPC Class Codes: G02F 1/133711 by organic films, e.g. polymeric films

Abstract

Provided is a liquid crystal alignment agent composition comprising a terminal modifier compound containing an amino group together with a polyimide containing an acid anhydride group at its terminus or a precursor polymer thereof, a method for preparing a liquid crystal alignment film using the same, and a liquid crystal alignment film and a liquid crystal display using the same.

Claims

1. A liquid crystal alignment agent composition comprising:

a terminal modifier compound containing an amino group; and

a polymer containing at least one repeating unit selected from the group consisting of a repeating unit of the following Chemical Formula 1, a repeating unit of the following Chemical Formula 2, and a repeating unit of the following Chemical Formula 3, in which an acid anhydride group is bonded to at least one terminus thereof;

2. The liquid crystal alignment agent composition according to claim 1, wherein in the Chemical Formula 4, A is nitrogen, R₃ is hydrogen, and a is 1.

3. The liquid crystal alignment agent composition according to claim 1, wherein the divalent organic group of the Chemical Formula 4 is selected from the group consisting of divalent organic groups of the following Chemical Formulas 4-1, 4-2, and 4-3:

4. The liquid crystal alignment agent composition according to claim 1, wherein X₁ to X₃ are each independently a tetravalent organic group having one of the following formulas:

5. The liquid crystal alignment agent composition according to claim 1, wherein the terminal modifier compound containing an amino group is a compound of the following Chemical Formula 6:

6. The liquid crystal alignment agent composition according to claim 1, wherein the content of the terminal modifier compound containing an amino group is 0.1% to 20% by weight based on the total weight of the liquid crystal alignment agent composition.

7. The liquid crystal alignment agent composition according to claim 1, wherein the polymer includes:

a first polymer containing at least one repeating unit selected from the group consisting of the repeating unit of the Chemical Formula 1, the repeating unit of the Chemical Formula 2, and the repeating unit of the Chemical Formula 3 in which an acid anhydride group is bonded to at least one terminus thereof; and

a second polymer containing at least one repeating unit selected from the group consisting of the repeating unit of the Chemical Formula 1, the repeating unit of the Chemical Formula 2, and the repeating unit of the Chemical Formula 3 and having at least one terminal functional group selected from the group consisting of the following Chemical Formulas 7, 8, and 9 at one or more termini thereof;

8. The liquid crystal alignment agent composition according to claim 7, wherein the second polymer is contained in an amount from 0.5% to 40% by weight based on the total weight of the liquid crystal alignment agent composition.

9. A method for preparing a liquid crystal alignment film, comprising the steps of:

coating the liquid crystal alignment agent composition of claim 1 onto a substrate to form a coating film;

drying the coating film;

irradiating the dried coating film with light or rubbing the dried coating film to perform alignment treatment; and

heat-treating and curing the alignment-treated coating film.

10. The method for preparing a liquid crystal alignment film according to claim 9, wherein the step of drying the coating film is performed at a temperature of 50°

C. to 150°

C.

11. The method for preparing a liquid crystal alignment film according to claim 9, wherein the step of heat-treating and curing the alignment-treated coating film is performed at a temperature of 180°

C. to 300°

C.

12. A liquid crystal alignment film, prepared by the method of claim claim 9.

13. A liquid crystal alignment film, comprising an aligned cured product of the liquid crystal alignment agent composition of claim 1.

14. A liquid crystal display, comprising the liquid crystal alignment film of claim 13.