LIQUID CRYSTAL DISPLAY AND METHOD FOR MANUFACTURING SAME

• US 20110301324A1
• Filed: 08/17/2011
• Published: 12/08/2011
• Est. Priority Date: 12/09/2002
• Status: Active Grant

• Current Assignee: Japan Display Incorporated
• Original Assignee: Japan Display Incorporated
• Inventors: Tomioka, Yasushi, Abe, Hidetoshi, Kondo, Katsumi
• Granted Patent: US 8,758,871 B2
• Time in Patent Office: Days
• US Class Current: 528/337
• CPC Class Codes: C09D 179/08 Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors
• CPC Class Codes: C09K 19/542 Macromolecular compounds
• CPC Class Codes: C09K 19/56 Aligning agents
• CPC Class Codes: C09K 2019/548 stabilizing the alignment; Polymer stabilized alignment
• CPC Class Codes: C09K 2323/00 Functional layers of liquid crystal optical display excluding electroactive liquid crystal layer characterised by chemical composition
• CPC Class Codes: C09K 2323/02 Alignment layer characterised by chemical composition
• CPC Class Codes: C09K 2323/025 Polyamide
• CPC Class Codes: C09K 2323/027 Polyimide
• CPC Class Codes: C09K 2323/0271 Polyimidfluoride
• CPC Class Codes: C09K 2323/03 Viewing layer characterised by chemical composition
• CPC Class Codes: G02F 1/133723 Polyimide, polyamide-imide
• CPC Class Codes: G02F 1/133788 by light irradiation, e.g. linearly polarised light photo-polymerisation
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]
• CPC Class Codes: G02F 2201/121 common or background
• CPC Class Codes: G02F 2201/123 pixel
• CPC Class Codes: G02F 2202/08 glass transition temperature

Abstract

A liquid crystal display is provided which is capable of reducing the occurrence of defective display due to variations in the initial alignment direction of a liquid crystal alignment control film in a liquid crystal display of an IPS scheme, realizing the stable liquid crystal alignment, providing excellent mass productivity, and having high image quality with a higher contrast ratio. The liquid crystal display has a liquid crystal layer disposed between a pair of substrates, at least one of the substrates being transparent, and an alignment control film formed between the liquid crystal layer and the substrate. At least one of the alignment control films 109 comprises photoreactive polyimide and/or polyamic acid provided with an alignment control ability by irradiation of substantially linearly polarized light.

Claims

1. An alignment control film comprising a polyamic acid or polyimide that includes cyclobutanetetracarboxylic acid dianhydride and/or its derivative and aromatic diamine;

and

wherein the cyclobutanetetracarboxylic acid dianhydride and/or its derivative is a compound represented by a formula [1];

2. The alignment control film according to claim 1, wherein said alignment control film is polyamic acid or polyimide containing at least 50% of a repeated structure of polyamic acid or polyimide comprising said cyclobutanetetracarboxylic acid dianhydride and/or its derivative and said aromatic diamine.

3. The alignment control film according to claim 2, wherein the aromatic diamine compound contains at least one of compounds selected from a group of compounds consisting of ones represented by formulas [2] to [16]:

4. The alignment control film according to claim 1, having a glass transition temperature equal to or higher than 250°

C.