Liquid crystal display device and method for manufacturing liquid crystal display device

Patent metadata

Field	Value
Publication number	US-10877304-B2
Application number	US-201616067517-A
Country	US
Kind code	B2
Filing date	Dec 28, 2016
Priority date	Jan 7, 2016
Publication date	Dec 29, 2020
Grant date	Dec 29, 2020

Abstract

With the use of a photoalignment film, the present invention provides a liquid crystal display device capable of maintaining a favorable voltage holding ratio and reducing or preventing image sticking, stains, and a decrease in contrast ratio for a long time not only in a room-temperature environment but also in a high-temperature environment; and a method for producing such a liquid crystal display device. The liquid crystal display device of the present invention includes paired substrates; a liquid crystal layer disposed between the substrates; a photoalignment film disposed between at least one of the substrates and the liquid crystal layer; and a polymer layer disposed between the photoalignment film and the liquid crystal layer, wherein the polymer layer has a structure derived from a specific epoxy-based monomer and a structure derived from a specific curing agent.

First claim

The invention claimed is:

1. A liquid crystal display device comprising:
paired substrates;
a liquid crystal layer disposed between the substrates;
a photoalignment film disposed between at least one of the substrates and the liquid crystal layer; and
a polymer layer disposed between the photoalignment film and the liquid crystal layer,
wherein the polymer layer has a structure derived from an epoxy-based monomer represented by the following formula (1) and a structure derived from a curing agent represented by the following formula (2):

wherein Ep represents an epoxy group;
R 1 and R 2 are the same as or different from each other and each represent an O group, an S group, an NH group, a CO group, a COO group, an OCO group, an NHCO group, a CONH group, a CH 2 group, a CH(CH 3 ) group, a C(CH 3 ) 2 group, a CF 2 group, or a direct bond;
A 1 and A 2 are the same as or different from each other and each represent a 1,4-phenylene group, a naphthalene-1,4-diyl group, a naphthalene-2,6-diyl group, a 1,4-cyclohexylene group, a C2-C18 alkylene group, or a C2-C18 unsaturated alkylene group;
CH 2 groups of A 1 and A 2 are each optionally replaced by an O group or an S group as long as they are not adjacent to each other;
one or more hydrogen atoms of A 1 and A 2 are each optionally replaced by a fluorine atom, a chlorine atom, a CN group, a C1-C6 alkyl group, a C1-C6 alkoxy group, a C1-C6 alkylcarbonyl group, a C1-C6 alkoxycarbonyl group, or a C1-C6 alkylcarbonyloxy group;
Z 1 represents an O group, an S group, an NH group, a CO group, a COO group, an OCO group, an NHCO group, a CONH group, a CH 2 group, a CH(CH 3 ) group, a C(CH 3 ) 2 group, a CF 2 group, or a direct bond;
Z 2 is a structure represented by the following formula (1-1);
n1 is 0, 1, 2, 3, 4, or 5; and
n2 is 0 or 1,

wherein n3 is an integer of 1 to 18,

wherein H 1 and H 2 are the same as or different from each other and each represent an amino group, a dimethylamino group, a hydrazide group, or an imidazole group;
R 3 and R 4 are the same as or different from each other and each represent an O group, an S group, an NH group, a CO group, a COO group, an OCO group, an NHCO group, a CONH group, a CH 2 group, a CH(CH 3 ) group, a C(CH 3 ) 2 group, a CF 2 group, or a direct bond;
A 3 and A 4 are the same as or different from each other and each represent a 1,4-phenylene group, a naphthalene-1,4-diyl group, a naphthalene-2,6-diyl group, a 1,4-cyclohexylene group, a C2-C18 alkylene group, a C2-C18 unsaturated alkylene group, or a CO or CO—CO group;
CH 2 groups of A 3 and A 4 are each optionally replaced by an O group, an S group, or an NH group as long as they are not adjacent to each other;
one or more hydrogen atoms of A 3 and A 4 are each optionally replaced by a fluorine atom, a chlorine atom, a CN group, a C1-C6 alkyl group, a C1-C6 alkoxy group, a C1-C6 alkylcarbonyl group, a C1-C6 alkoxycarbonyl group, or a C1-C6 alkylcarbonyloxy group;
Z 3 represents an O group, an S group, an NH group, a CO group, a COO group, an OCO group, an NHCO group, a CONH group, a CH 2 group, a CH(CH 3 ) group, a C(CH 3 ) 2 group, a CF 2 group, or a direct bond; and
n4 is 0, 1, 2, 3, 4, or
wherein the epoxy-based monomer is a monomer represented by the following formula (3), and the curing agent is a monomer represented by the following formula (4):

wherein n5 is an integer of 1 to 6,

2. The liquid crystal display device according to claim 1 ,
wherein the photoalignment film contains a photoreactive functional group-containing polymer, and
the photoreactive functional group is an azobenzene group, a chalcone group, or a cinnamate group.

3. The liquid crystal display device according to claim 2 ,
wherein the photoreactive functional group-containing polymer further contains a carboxyl group.

4. The liquid crystal display device according to claim 2 ,
wherein the photoreactive functional group-containing polymer further contains an epoxy group.

5. The liquid crystal display device according to claim 1 ,
wherein the photoalignment film contains a polymer containing a carboxyl group.

6. The liquid crystal display device according to claim 1 ,
wherein the photoalignment film contains a polymer containing an epoxy group.

7. The liquid crystal display device according to claim 3 ,
wherein the carboxyl group and the epoxy-based monomer are bonded to each other.

8. The liquid crystal display device according to claim 4 ,
wherein the epoxy group and the curing agent are bonded to each other.

9. The liquid crystal display device according to claim 1 ,
wherein the photoalignment film contains a polymer selected from the group consisting of a polyamic acid, a polyimide, a polysiloxane, a polyvinyl, and polymaleimide.

10. The liquid crystal display device according to claim 1 ,
wherein the liquid crystal layer contains a liquid crystal material having negative anisotropy of dielectric constant.

11. The liquid crystal display device according to claim 1 ,
wherein the display mode of the liquid crystal display device is a twisted nematic (TN) mode, an electrically controlled birefringence (ECB) mode, an in-plane switching (IPS) mode, a fringe-field switching (FFS) mode, a vertical alignment (VA) mode, or a vertical alignment twisted nematic (VATN) mode.

Assignees

• Sharp Kk

Inventors

• Mizusaki Masanobu
• Tsuchiya Hiroshi

Classifications

• C09K19/542 Primary

  Macromolecular compounds · CPC title

• C09K2019/0448

  the end chain group being a polymerizable end group, e.g. -Sp-P or acrylate · CPC title

• C08G59/5033

  aromatic · CPC title

• G02F1/133788

  by light irradiation, e.g. linearly polarised light photo-polymerisation · CPC title

• C08L2203/20

  use in electrical or conductive gadgets · CPC title