Liquid crystal display device, method for producing liquid crystal display device, and monomer material for retardation layer

Patent metadata

Field	Value
Publication number	US-10831065-B2
Application number	US-201916296115-A
Country	US
Kind code	B2
Filing date	Mar 7, 2019
Priority date	Mar 9, 2018
Publication date	Nov 10, 2020
Grant date	Nov 10, 2020

Abstract

The present invention provides a liquid crystal display device that includes a retardation layer with excellent thermal stability and suppresses a decrease in contrast ratio caused by scattering even when the retardation layer has been formed by polymerizing reactive monomers. The liquid crystal display device includes a pair of substrates and a liquid crystal layer held between the substrates. At least one of the substrates includes a retardation layer that contains a polymer of at least one type of monomer. The at least one type of monomer includes a photo-alignment monomer represented by a certain formula.

First claim

What is claimed is:

1. A liquid crystal display device comprising:
a pair of substrates, and
a liquid crystal layer held between the substrates,
at least one of the substrates including a retardation layer that contains a polymer of at least one type of monomer,
the at least one type of monomer including a photo-alignment monomer represented by the following formula (1):

wherein P 1 and P 2 are the same as or different from each other and each represent an acrylic group or a methacrylic group; Sp 1 , Sp 2 , Sp 3 , and Sp 4 are the same as or different from each other and each represent —O—, —S—, —NH—, —COO—, —OCO—, —NHCO—, —CONH—, —NHCS—, —CSNH—, or a direct bond; Z 1 and Z 2 are the same as or different from each other and each represent a C1-C12 linear, branched, or cyclic alkylene group, or a direct bond; X 1 and X 2 are the same as or different from each other and each represent —NH— or —O—; and any hydrogen atom in the biphenyl group may be replaced by a fluorine atom;
wherein the photo-alignment monomer is represented by the following formula (2-1), (2-2), (2-3), (2-4), (2-5), (2-6), or (2-7):

and
wherein any methacrylic group in the formulas (2-1), (2-2), (2-3), (2-4), (2-5), (2-6), and (2-7) may be replaced by an acrylic group, and m and n in the formulas (2-3), (2-5), and (2-7) are the same as or different from each other and each represent an integer of 1 to 12.

2. The liquid crystal display device according to claim 1 ,
wherein the photo-alignment monomer is represented by the following formula (3-1), (3-2), (3-3), (3-4), (3-5), (3-6), or (3-7):

and
wherein, any methacrylic group in the formulas (3-1), (3-2), (3-3), (3-4), (3-5), (3-6), and (3-7) may be replaced by an acrylic group, and m and n in the formulas (3-3), (3-5), and (3-7) are the same as or different from each other and each represent an integer of 1 to 12.

3. The liquid crystal display device according to claim 1 ,
wherein the liquid crystal display device further includes, between at least one of the substrates and the liquid crystal layer, an alignment film that controls alignment of liquid crystal molecules in the liquid crystal layer.

4. The liquid crystal display device according to claim 3 ,
wherein the alignment film is a horizontal alignment film that aligns the liquid crystal molecules in the liquid crystal layer in a direction parallel to a surface of the alignment film.

5. The liquid crystal display device according to claim 3 ,
wherein the alignment film is a photo-alignment film.

6. The liquid crystal display device according to claim 5 ,
wherein the photo-alignment film contains a polymer containing a cinnamate group.

7. The liquid crystal display device according to claim 5 ,
wherein the photo-alignment film contains a polymer with a structure derived from a cyclobutane ring.

8. A monomer material for a retardation layer, comprising at least one type of monomer including a photo-alignment monomer represented by the following formula (1):

wherein P 1 and P 2 are the same as or different from each other and each represent an acrylic group or a methacrylic group; Sp 1 , Sp 2 , Sp 3 , and Sp 4 are the same as or different from each other and each represent —O—, —S—, —NH—, —COO—, —OCO—, —NHCO—, —CONH—, —NHCS—, —CSNH—, or a direct bond; Z 1 and Z 2 are the same as or different from each other and each represent a C1-C12 linear, branched, or cyclic alkylene group, or a direct bond; X 1 and X 2 are the same as or different from each other and each represent —NH— or —O—; and any hydrogen atom in the biphenyl group may be replaced by a fluorine atom;
wherein the photo-alignment monomer is represented by the following formula (2-1), (2-2), (2-3), (2-4), (2-5), (2-6), or (2-7):

and
wherein any methacrylic group in the formulas (2-1), (2-2), (2-3), (2-4), (2-5), (2-6), and (2-7) may be replaced by an acrylic group, and m and n in the formulas (2-3), (2-5), and (2-7) are the same as or different from each other and each represent an integer of 1 to 12.

9. The monomer material according to claim 8 ,
wherein the photo-alignment monomer is represented by the following formula (3-1), (3-2), (3-3), (3-4), (3-5), (3-6), or (3-7):

and
wherein, any methacrylic group in the formulas (3-1), (3-2), (3-3), (3-4), (3-5), (3-6), and (3-7) may be replaced by an acrylic group, and m and n in the formulas (3-3), (3-5), and (3-7) are the same as or different from each other and each represent an integer of 1 to 12.

Assignees

• Sharp Kk

Inventors

• Mizusaki Masanobu

Classifications

• G02F1/133715

  by first depositing a monomer · CPC title

• G02F1/136222

  Colour filters incorporated in the active matrix substrate · CPC title

• C09K19/2014 Primary

  containing additionally a linking group other than -COO- or -OCO-, e.g. -CH2-CH2-, -CH=CH-, -C=C-; containing at least one additional carbon atom in the chain containing -COO- or -OCO- groups, e.g. -(CH2)m-COO-(CH2)n- · CPC title

• C09K2019/548

  stabilizing the alignment; Polymer stabilized alignment · CPC title

• G02F1/133723

  Polyimide, polyamide-imide · CPC title