Polarizing film, laminated film, and liquid crystal display

• US 20060210803A1
• Filed: 08/05/2004
• Published: 09/21/2006
• Est. Priority Date: 08/08/2003
• Status: Abandoned Application

• Current Assignee: Nitto Denko Corporation
• Original Assignee: Nitto Denko Corporation
• Inventors: Ishibashi, Kuniaki, Yoshimi, Hiroyuki
• Application Number:
  US10/566,714
• Publication Number:
  US 20060210803A1
• Time in Patent Office: Days
• US Class Current: 428/411.100
• CPC Class Codes: B32B 33/00 Layered products characterised by particular properties or particular surface features, e.g. particular surface coatings; Layered products designed for particular purposes not covered by another single class
• CPC Class Codes: B32B 38/0012 Mechanical treatment, e.g. roughening, deforming, stretching
• CPC Class Codes: C09K 2323/031 Polarizer or dye
• CPC Class Codes: G02B 5/3033 in the form of a thin sheet or foil, e.g. Polaroid
• CPC Class Codes: Y10T 428/31504 Composite [nonstructural laminate]

Abstract

The invention provides a polarizing film comprising: a long polymer film; and a dichroic substance, wherein the polarizing film has an absorption axis in the TD direction of the polarizing film.

Claims

1. A polarizing film comprising:

a long polymer film; and

a dichroic substance,

wherein the polarizing film has an absorption axis in the TD direction of the polarizing film.

2. The polarizing film according to claim 1,

wherein the length in the MD direction of the polarizing film is not smaller than five times as long as the length in the TD direction of the polarizing film.

3. The polarizing film according to claim 1,

wherein the polarizing film is produced by stretching the long polymer film in the TD direction.

4. The polarizing film according to claim 1,

wherein the polarizing film is produced by:

stretching the long polymer film in the TD direction; and

shrinking the long polymer film in the MD direction.

5. The polarizing film according to claim 1,

wherein the polarizing film is produced by dyeing the long polymer, which is stretched in the TD direction, with a iodine by using an aqueous solution containing the iodine.

6. The polarizing film according to claim 1,

wherein the polarizing film is produced by dyeing the long polymer, which is stretched in the TD direction and shrunk in the MD direction, with a iodine by using an aqueous solution containing the iodine.

7. The polarizing film according to claim 5,

wherein the polarizing film is produced by dyeing the long polymer film with the iodine by applying the aqueous solution containing the iodine onto the long polymer film.

8. A laminated film comprising:

a polarizing film according to claim 1;

and

a retardation film having a slow axis in the MD direction, which comprises a long polymer film,

wherein the MD direction of the polarizing film corresponds to the MD direction of the retardation film.

9. The laminated film according to claim 8,

wherein the retardation film comprises a uniaxially stretched film.

10. The laminated film according to claim 8,

wherein the retardation film comprises an optically uniaxial layer comprising a liquid crystal material.

11. The laminated film according to claim 8,

wherein the retardation film comprises a birefringent layer comprising a non-liquid crystal material having a birefringence of not lower than 0.005.

12. The laminated film according to claim 8,

wherein the retardation film is a composite film comprising a birefringent layer provided on a birefringent polymer film.

13. The laminated film according to claim 11 or 12,

wherein the birefringent layer comprises a solid polymer containing at least one selected from:

polyetherketone;

polyamide;

polyester;

polyimide;

polyamideimide; and

polyesterimide.

14. The laminated film according to claim 13,

wherein the birefringent layer is a solid polymer comprising polyimide.

15. The laminated film according to claim 11 or 12,

wherein the birefringent layer has a relationship nx>

ny>

nz,

wherein nx is the maximum in-plane refractive index, ny is an in-plane refractive index in a direction perpendicular to the direction of nx, and nz is a thicknesswise refractive index.

16. A liquid crystal display comprising a polarizing film according to claim 1 that is disposed outside of a liquid crystal cell.

17. A liquid crystal display comprising a laminated film according to claim 8 that is disposed outside of a liquid crystal cell.

18. A process for producing a polarizing film comprising:

unrolling a polymer film successively;

stretching the polymer film in the TD direction; and

dyeing the stretched film.

19. The process for producing a polarizing film according to claim 18;

wherein the stretching in the TD direction is carried out by a tenter stretching machine.