Light transmitting and reflecting polarizer

• US 4,268,127 A
• Filed: 04/20/1979
• Issued: 05/19/1981
• Est. Priority Date: 09/29/1978
• Status: Expired due to Term

• Current Assignee: Nitto Electric Industrial Co., Ltd. (Nitto Denko Corporation)
• Original Assignee: Nitto Electric Industrial Co., Ltd. (Nitto Denko Corporation)
• Inventors: Oshima, Nobuo, Maeda, Sajiro
• Primary Examiner(s): Bauer, Edward S.
• Application Number:
  US06/031,798
• Time in Patent Office: 760 Days
• Field of Search: 350/337, 350/339 D, 350/345, 350/155, 350/188, 428/363, 428/402, 428/403
• US Class Current: 349/96
• CPC Class Codes: G02B 5/3033 in the form of a thin sheet or foil, e.g. Polaroid
• CPC Class Codes: G02F 1/133528 Polarisers

Abstract

A new and useful light transmitting and reflecting polarizer is disclosed comprising a transparent or semi-transparent resin film, an adhesive layer having uniformly dispersed therein transparent and/or semi-transparent particles, and a polarizing layer. This polarizer is useful in liquid crystal display devices.

Claims

1. A light transmitting and reflecting polarizer comprising a transparent or semi-transparent resin film, an adhesive layer having uniformly dispersed therein transparent and/or semi-transparent particles, and a polarizing layer, said resin film and said polarizing layer being bonded through said adhesive layer.

2. The polarizer of claim 1, wherein said resin film is a transparent film having a thickness of about 10 to 500 microns.

3. The polarizer of claim 2, wherein said film is selected from the group consisting of an acrylate resin film, a (meth)acrylate film, an acetate resin film, a polycarbonate resin film, a polyester resin film and a polyurethane resin film.

4. The polarizer of claim 1, wherein said semi-transparent resin film is selected from the group consisting of (a) a semi-transparent film having surface light diffusing and transmitting ability, (b) a semi-transparent film having internal light diffusing and transmitting ability and (c) a semi-transparent film having surface and internal light diffusing and transmitting ability.

5. The polarizer of claim 4, wherein said semi-transparent film (a) has minute projections and depressions on at least one surface thereof and a light transmittance of at least about 40%.

6. The polarizer of claim 5, wherein the distance between said projections is about 0.1 to 50 microns, the perpendicular depth from the top of said projections to the bottom of said depressions is about 0.1 to 10 microns and the number of said projections or depressions is about 1,000 to 100,000/mm².

7. The polarizer of claim 4, wherein said semi-transparent film (b) has a thickness of about 10 to 500 microns and a light transmittance of at least about 10%.

8. The polarizer of claim 4, wherein said semi-transparent film (b) contains light diffusing materials.

9. The polarizer of claim 8, wherein the amount of said light diffusing material is about 0.3 to 30% by weight based on the weight of said film.

10. The polarizer of claim 8, wherein said light diffusing material have a particle diameter of about 0.01 to 30 microns.

11. The polarizer of claim 8, wherein said light diffusing materials are selected from the group consisting of metal powders, metal oxide powders, rare earth metal oxide powders and alkaline earth metal oxide powders.

12. The polarizer of claim 4, wherein said semi-transparent film (b) has an internal light diffusing structure.

13. The polarizer of claim 12, wherein said internal light diffusing structure is a structure comprising voids.

14. The polarizer of claim 13, wherein said semi-transparent film (b) having an internal structure comprising an assembly of voids has a thickness of about 0.03 to 1 mm and a light transmittance of at least about 10%.

15. The polarizer of claim 13, wherein said semi-transparent film (b) having an internal structure comprising fibers having voids therebetween has a thickness of about 0.03 to 1.5 mm and a light transmittance of at least about 10%.

16. The polarizer of claim 1, wherein said adhesive layer has a light transmittance of at least about 10%.

17. The polarizer of claim 1, wherein said transparent and/or semi-transparent particles have a refractive index of at least about 1.5 and have a particle diameter of about 0.1 to 180 microns.

18. The polarizer of claim 1, wherein the amount of said transparent and/or semi-transparent particles is about 3 to 60% by weight based on the weight of the adhesive layer.

19. The polarizer of claim 1, wherein said transparent and/or semi-transparent particles have a circular shape, a granular shape, a bead shape, a scale shape, a needle shape or a dendritic shape.

20. The polarizer of claim 1, wherein said transparent and/or semi-transparent particles are scale shaped particles.

21. The polarizer of claim 20, wherein said scale shaped particles have an average diameter of about 3 to 10 microns and a thickness of about 0.1 times or less the average diameter.

22. The polarizer of claim 1, wherein said transparent and/or semi-transparent particles are mica flake coated with a thin film of titanium dioxide.

23. The polarizer of claim 22, wherein said titanium dioxide has a particle diameter of about 0.03 to 0.08 micron.

24. In a liquid crystal display device the improvement which comprises:

a transmitting and reflecting polarizer comprising a transparent or semi-transparent resin film, an adhesive layer having uniformly dispersed therein transparent and/or semi-transparent particles, and a polarizing layer, said resin film and said polarizing layer being bonded through said adhesive layer.