Optical film, polarizing plate, and image display device

Patent metadata

Field	Value
Publication number	US-10908338-B2
Application number	US-201916266889-A
Country	US
Kind code	B2
Filing date	Feb 4, 2019
Priority date	Aug 12, 2016
Publication date	Feb 2, 2021
Grant date	Feb 2, 2021

Abstract

The present invention provides an optical film exhibiting high alignment and good phase difference development in an oblique direction, and a polarizing plate and an image display device using the same. This optical film of the present invention has a substrate; and a phase difference layer which is provided on the substrate to be adjacent to the substrate, in which the phase difference layer is a layer formed by fixing vertical alignment of a liquid crystal compound having a polymerizable group included in a liquid crystal composition containing the liquid crystal compound and a polymer compound, a difference in δa value between the polymer compound and the substrate, which is calculated using three-dimensional SP values, is 3 or less, and a content of the polymer compound is less than 10 parts by mass with respect to 100 parts by mass of the liquid crystal compound.

First claim

What is claimed is:

1. An optical film comprising:
a substrate; and
a phase difference layer which is provided on the substrate to be adjacent to the substrate,
wherein the phase difference layer is a layer formed by fixing vertical alignment of a liquid crystal compound having a polymerizable group included in a liquid crystal composition containing the liquid crystal compound and a polymer compound,
a difference in δa value between the polymer compound and the substrate, which is calculated using three-dimensional SP values, is 3 or less,
a content of the polymer compound is less than 10 parts by mass with respect to 100 parts by mass of the liquid crystal compound,
wherein the polymer compound is a polymer having a repeating unit represented by Formula (I),

in Formula (I), R 1 represents a hydrogen atom or a methyl group; X represents —O— or —NH—; and R 2 represents a hydrogen atom or an organic group; the organic group includes a hydrophilic group, and the hydrophilic group is a group selected from the group consisting of a hydroxy group, a carboxy group, an amino group, a sulfo group, a sulfate group, a phosphonoxy group, and salts thereof, and
wherein the polymer compound does not have a fluorine atom.

2. The optical film according to claim 1 ,
wherein an amount of the polymer compound present on a surface of the phase difference layer close to the substrate is larger than an amount of the polymer compound present on a surface of the phase difference layer opposite to the substrate.

3. The optical film according to claim 1 ,
wherein the polymer compound has a hydrophilic group.

4. The optical film according to claim 1 ,
wherein the polymer compound has a hydrophilic group, and
the liquid crystal composition contains an onium salt compound.

5. The optical film according to claim 1 ,
wherein the polymer compound has a hydrophilic group, and
the liquid crystal composition contains a boronic acid compound.

6. The optical film according to claim 1 ,
wherein a δa value of the substrate, which is calculated using three-dimensional SP values, is 10 or more.

7. The optical film according to claim 1 ,
wherein a δa value of the polymer compound, which is calculated using three-dimensional SP values, is 15 to 19.

8. The optical film according to claim 1 ,
wherein the polymer compound has a mesogen group represented by Formula (M),
-L-X-(A-Y) n -Z  (M)

here, L represents a linking group having 1 to 8 carbon atoms; X and Y each independently represent a single bond, —O—, —C(O)O—, —OC(O)—, —OC(O)O—, —C(O)OCH 2 CH 2 —, or —CH 2 CH 2 C(O)O—; A represents a 1,4-phenylene group, a 2,6-naphthylene group, or a 1,4-transcyclohexylene group which may have a substituent; Z represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 1 to 8 carbon atoms, a halogen atom, a cyano group, or -L 1 -P, where L 1 represents a linking group having 1 to 8 carbon atoms, and P represents a polymerizable group; n represents an integer of 2 to 5; and in a case where n is an integer of 2 or greater, a plurality of A's may be the same or different from each other; and a plurality of Y's may be the same or different from each other.

9. The optical film according to claim 1 ,
wherein a δa value of the substrate, which is calculated using three-dimensional SP values, is 10 or more, and
the polymer compound is a polymer having a repeating unit having a δa value of 13 or more and less than 18, the δa value being calculated using three-dimensional SP values.

10. The optical film according to claim 1 ,
wherein a δa value of the substrate, which is calculated using three-dimensional SP values, is 5 or more and less than 10, and
the polymer compound is a polymer having a repeating unit having a δa value of 5 or more and less than 11, the δa value being calculated using three-dimensional SP values.

11. A polarizing plate comprising: the optical film according to claim 1 .

12. A polarizing plate comprising: the optical film according to claim 8 .

13. The polarizing plate according to claim 11 , further comprising:
a polarizer.

14. The polarizing plate according to claim 12 , further comprising:
a polarizer.

15. An image display device comprising:
the optical film according to claim 1 .

16. An image display device comprising:
the optical film according to claim 8 .

17. An image display device comprising:
the polarizing plate according to claim 12 .

18. An image display device comprising:
the polarizing plate according to claim 14 .

Assignees

• Fujifilm Corp

Inventors

• Katoh Shunya
• Iijima Koji
• Ichihashi Mitsuyoshi
• Yoshikawa Masaru

Classifications

• H10K59/8791

  Arrangements for improving contrast, e.g. preventing reflection of ambient light · CPC title

• C08J2345/00

  Characterised by the use of homopolymers or copolymers of compounds having no unsaturated aliphatic radicals in side chain, and having one or more carbon-to-carbon double bonds in a carbocyclic or in a heterocyclic ring system; Derivatives of such polymers · CPC title

• C08J2467/07

  having terminal carbon-to-carbon unsaturated bonds · CPC title

• C09K19/3444

  the heterocyclic ring being a six-membered aromatic ring containing one nitrogen atom, e.g. pyridine · CPC title

• G02F1/13363

  Birefringent elements, e.g. for optical compensation · CPC title