Polymer for use in liquid crystal alignment layer

Patent metadata

Field	Value
Publication number	US-9340634-B2
Application number	US-201113522801-A
Country	US
Kind code	B2
Filing date	Mar 29, 2011
Priority date	Mar 29, 2010
Publication date	May 17, 2016
Grant date	May 17, 2016

Abstract

The present invention relates to materials used for aligning liquid crystals of liquid crystal display elements and to a polymer for use in liquid crystal vertical alignment layer used in producing a liquid crystal vertical alignment layer.
The polymer for use in a liquid crystal vertical alignment layer includes (a) a moiety that is photochemically isomerizable but not photochemically crosslinked, (b) a moiety that is photochemically crosslinkable, and (c) a moiety that stabilizes a vertical alignment. The polymer can be used to produce a vertical alignment layer that has a liquid crystal alignment property enabling control of alignment at a low UV dose and that offers a large pretilt angle and superior optical stability.

First claim

The invention claimed is:

1. A polymer for use in a liquid crystal vertical alignment layer, comprising (a) a moiety that is photochemically isomerizable but not photochemically crosslinked; (b) a moiety that is photochemically crosslinkable; and (c) a moiety that stabilizes a vertical alignment.

2. The polymer for use in a liquid crystal vertical alignment layer according to claim 1 , wherein the polymer is a cured product of monomers represented by general formulae (Iaaa-1), (Iaaa-2), and (Iaaa-3):
M a -S a -P  (Iaaa-1)

M b -S b -D  (Iaaa-2)

M c -S c -V c   (Iaaa-3)

(where M a , M b , and M c each represent a monomer unit of the polymer and may be different from one another; S a , S b , and S c each represent a spacer unit and may be different from one another; P represents a moiety that is photochemically isomerizable but not photochemically crosslinked; D represents a moiety that is photochemically crosslinkable; and V c represents a moiety that stabilizes a vertical alignment).

3. The polymer for use in a liquid crystal vertical alignment layer according to claim 2 , further comprising one monomer unit or two or more different monomer units each represented by a formula selected from the group consisting of the following formulae (QIII-1) to (QIII-17):

(where a broken line represents a bond to a monovalent organic group; R independently represents hydrogen or an alkyl group having 1 to 5 carbon atoms; any hydrogen in each structure may be substituted with a fluorine atom, a chlorine atom, a methyl group, or a methoxy group; and said monovalent organic group is hydrogen or an alkyl group having 1 to 12 carbon atoms (i) in which any hydrogen atom in the alkyl group may be substituted with a fluorine atom, a chlorine atom, a methyl group, or a methoxy group and (ii) in which one CH 2 group or two or more non-neighboring CH 2 groups in the alkyl group may be substituted with —O—, —CO—O—, —O—CO—, —CH═CH—, a trans-1,4-cyclohexylene group, a trans-1,3-dioxan-2,5-yl group, a 1,4-naphthylene group, a 2,6-naphthylene group, a 2,5-thiophenylene group, a 2,5-furanylene group, or 1,4-phenylene group in which any hydrogen of each group may be substituted with a fluorine atom, a chlorine atom, a methyl group, or a methoxy group),
wherein the polymer has a structural unit represented by general formula (Iaaa):

(where M a , M b , M c , and Q each represent a monomer unit of the polymer and may be different from one another; x, y, z, and w each represent a molar fraction of the monomer unit in the polymer and satisfy 0<x<1, 0<y<1, 0<z<1, and 0≦w<1; S a , S b , and S c each represent a spacer unit and may be different from one another; P represents a moiety that is photochemically isomerizable but not photochemically crosslinked; D represents a moiety that is photochemically crosslinkable; V c represents a moiety that stabilizes a vertical alignment; n represents 4 to 100,000; the order in which M a , M b , M c , and Q are arranged may be the same as or different from that shown in the formula (Iaaa); and Q is said one monomer unit or two or more different monomer units each represented by any of the formulae (QIII-1) to (QIII-17)).

4. The polymer for use in a liquid crystal vertical alignment layer according to claim 1 , wherein the polymer is a cured product of monomers represented by general formulae (Ibbb-1) and (Ibbb-2):
M a -S a -P-S aa -V a   (Ibbb-1)

M b -S b -D  (Ibbb-2)

(where M a and M b each represent a monomer unit of the polymer and may be different from one another; S a , S b , and S aa each represent a spacer unit and may be different from one another; P represents a moiety that is photochemically isomerizable but not photochemically crosslinked; D represents a moiety that is photochemically crosslinkable; and V a represents a moiety that stabilizes a vertical alignment).

5. The polymer for use in a liquid crystal vertical alignment layer according to claim 4 , further comprising one monomer unit or two or more different monomer units each represented by a formula selected from the group consisting of the following formulae (QIII-1) to (QIII-17):

(where a broken line represents a bond to a monovalent organic group; R independently represents hydrogen or an alkyl group having 1 to 5 carbon atoms; any hydrogen in each structure may be substituted with a fluorine atom, a chlorine atom, a methyl group, or a methoxy group; and said monovalent organic group is hydrogen or an alkyl group having 1 to 12 carbon atoms (i) in which any hydrogen atom in the alkyl group may be substituted with a fluorine atom, a chlorine atom, a methyl group, or a methoxy group and (ii) in which one CH 2 group or two or more non-neighboring CH 2 groups in the alkyl group may be substituted with —O—, —CO—O—, —O—CO—, —CH═CH—, a trans-1,4-cyclohexylene group, a trans-1,3-dioxan-2,5-yl group, a 1,4-naphthylene group, a 2,6-naphthylene group, a 2,5-thiophenylene group, a 2,5-furanylene group, or 1,4-phenylene group in which any hydrogen of each group may be substituted with a fluorine atom, a chlorine atom, a methyl group, or a methoxy group),
wherein the polymer has a structural unit represented by general formula (Ibbb):

(where M a , M b , and Q each represent a monomer unit of the polymer and may be different from one another; x, y, and w each represent a molar fraction of the monomer unit in the polymer and satisfy 0<x<1, 0<y<1, and 0≦w<1; S a , S b , and S aa each represent a spacer unit and may be different from one another; P represents a moiety that is photochemically isomerizable but not photochemically crosslinked; D represents a moiety that is photochemically crosslinkable; V a represents a moiety that stabilizes a vertical alignment; n represents 4 to 100,000; the order in which M a , M b , and Q are arranged may be the same as or different from that shown in the formula (Ibbb); and Q is said one monomer unit or two or more different monomer units each represented by any of the formulae (QIII-1) to (QIII-17)).

6. The polymer for use in a liquid crystal vertical alignment layer according to claim 1 , wherein the polymer is a cured product of monomers represented by general formulae (Iccc-1) and (Iccc-2):
M a -S a -D-S aa -V a   (Iccc-1)

M b -S b -P  (Iccc-2)

(where M a and M b each represent a monomer unit of the polymer and may be different from one another; S a , S b , and S aa each represent a spacer unit and may be different from one another; P represents a moiety that is photochemically isomerizable but not photochemically crosslinked; D represents a moiety that is photochemically crosslinkable; and V a represents a moiety that stabilizes a vertical alignment).

7. The polymer for use in a liquid crystal vertical alignment layer according to claim 6 , further comprising one monomer unit or two or more different monomer units each represented by a formula selected from the group consisting of the following formulae (QIII-1) to (QIII-17):

Assignees

• Nose Sayaka
• Nagashima Yutaka
• Nishiyama Isa
• Takatsu Haruyoshi
• Schadt Martin
• Chigrinov Vladimir
• Kwok Hoi Sing
• Dainippon Ink & Chemicals

Inventors

• Nose Sayaka
• Nagashima Yutaka
• Nishiyama Isa
• Takatsu Haruyoshi
• Schadt Martin
• Chigrinov Vladimir
• Kwok Hoi Sing

Classifications

• C08F220/365

  containing further carboxylic moieties · CPC title

• C08F220/305

  and containing a polyether chain in the alcohol moiety · CPC title

• C08F20/36

  containing oxygen in addition to the carboxy oxygen {, e.g. 2-N-morpholinoethyl (meth)acrylate or 2-isocyanatoethyl (meth)acrylate} · CPC title

• G02F1/1337

  Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers · CPC title

• C08F220/26

  Esters containing oxygen in addition to the carboxy oxygen · CPC title