Optical film, polarizing plate and liquid crystal display device including an optically anisotropic layer formed from a mixture including two or more liquid crystal compounds

• US 7,944,530 B2
• Filed: 11/14/2006
• Issued: 05/17/2011
• Est. Priority Date: 11/14/2005
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Inventors: Ikeda, Akira, Nagai, Michio
• Primary Examiner(s): Healy; Brian M.
• Assistant Examiner(s): Inadomi; Michael
• Application Number:
  US12/093,416
• Publication Number:
  US 20090096961A1
• Time in Patent Office: 1,645 Days
• Field of Search: 252/299.62, 252/299.01, 428/1.1, 428/1.3, 428/1.31, 349/117
• US Class Current: 349/117
• CPC Class Codes: C09K 2323/03 Viewing layer characterised by chemical composition
• CPC Class Codes: G02B 5/3016 involving passive liquid crystal elements optical properties of liquid crystals G02F1/0063; polarising elements associated with active liquid crystal devices G02F1/133528
• CPC Class Codes: G02F 1/133632 with refractive index ellipsoid inclined relative to the LC-layer surface
• CPC Class Codes: G02F 1/1395 Optically compensated birefringence [OCB]- cells or PI- cells
• CPC Class Codes: G02F 2413/105 with varying inclination in thickness direction, e.g. hybrid oriented discotic LC
• CPC Class Codes: Y10T 428/261 In terms of molecular thickness or light wave length

Abstract

An optical film, which is an optically compensatory film that comprises: at least two optically anisotropic layers comprising a first optically anisotropic layer and a second optically anisotropic layer, wherein the first optically anisotropic layer is formed by mixing two or more liquid crystal compounds having different structures with each other.

Claims

1. An optical film, which comprises:

at least two optically anisotropic layers comprising a first optically anisotropic layer and a second optically anisotropic layer,

wherein the first optically anisotropic layer is formed from a mixture which comprises two or more liquid crystal compounds having different structures from each other, wherein each of the two or more liquid crystal compounds has a polymerizable group,

wherein each of the two or more liquid crystal compounds is a discotic liquid crystal compound,

wherein at least one of the two or more liquid crystal compounds is a trisubstituted benzene skeleton discotic liquid crystal compound of the formula (D1);

2. The optical film according to claim 1, wherein H¹, H² and H³ each independently represents one of formula (DI-A) or (DI-B);

wherein in the formula (DI-A), YA¹ and YA² each independently represents a nitrogen atom, and XA represents an oxygen atom;

wherein in the formula (DI-B), YB¹ and YB² each independently represents a nitrogen atom, and XB represents an oxygen atom.

3. The optical film according to claim 1, wherein the two or more liquid crystal compounds having different structures from each other include a compound having a maximum absorption wavelength of from 200 to 250 nm, and a compound having a maximum absorption wavelength of from 270 to 320 nm.