Polarizing plate assembly

Patent metadata

Field	Value
Publication number	US-11059272-B2
Application number	US-201916730082-A
Country	US
Kind code	B2
Filing date	Dec 30, 2019
Priority date	Oct 29, 2013
Publication date	Jul 13, 2021
Grant date	Jul 13, 2021

Abstract

There is provided a polarizing plate, including: a polarizing layer having a thickness not greater than 20 μm; a first protective film stacked on one surface of the polarizing layer, with a first adhesive layer formed from an active energy ray curing adhesive being interposed; and a second protective film stacked on the other surface of the polarizing layer, with a second adhesive layer formed from a water-soluble adhesive being interposed. There are also provided a polarizing plate with a pressure sensitive adhesive layer, a substrate having a polarizing plate bonded thereto, a liquid crystal display device, and an organic electroluminescence display device, all of which include the polarizing plate. Preferably, at least one of the first protective film and the second protective film has a moisture permeability not higher than 1000 g/m2/24 hr.

First claim

The invention claimed is:

1. A polarizing plate assembly, comprising a polarizing plate and a transparent pressure sensitive adhesive layer,
the polarizing plate including:
a polarizing layer having a thickness not greater than 20 μm;
a first protective film stacked on one surface of the polarizing layer, with a first adhesive layer formed from an active energy ray curing adhesive interposed therebetween; and
a second protective film stacked on the other surface of the polarizing layer, with a second adhesive layer formed from a water-soluble adhesive interposed therebetween, and
the transparent pressure sensitive adhesive layer being located on a side of the polarizing plate having the first protective film, wherein
the first protective film or the second protective film has a thickness not greater than 50 μm,
a tensile elastic modulus at 80° C. of the first protective film or the second protective film is not lower than 1500 MPa and not higher than 10000 MPa,
the polarizing plate has a rectangular shape having a diagonal length of 3 to 32 cm, and
a surface of the second protective film has a root mean square roughness Rms of not greater than 86 nm, the surface being a surface on an opposite side of the polarizing layer.

2. The polarizing plate assembly according to claim 1 , wherein
at least one of the first protective film and the second protective film has a moisture permeability not higher than 1000 g/m2/24 hr.

3. The polarizing plate assembly according to claim 1 , wherein
the second protective film has a moisture permeability of 10 to 1000 g/m2/24 hr.

4. The polarizing plate assembly according to claim 1 , wherein
the polarizing layer is a stretched polyvinyl alcohol-based resin layer containing a dichroic colorant.

5. The polarizing plate assembly according to claim 1 , wherein
the polarizing layer has a thickness not greater than 10 μm.

6. The polarizing plate assembly according to claim 1 , further comprising
a surface treatment layer stacked on a surface of the first protective film or the second protective film, the surface being a surface on an opposite side of the polarizing layer.

7. The polarizing plate assembly according to claim 6 , wherein
the surface treatment layer is a hard coat layer, an antireflective layer or an electroconductive layer.

8. The polarizing plate assembly according to claim 1 , wherein
the polarizing plate assembly is disposed at a viewing side of a image display element.

9. A substrate having a polarizing plate bonded thereto, comprising:
the polarizing plate assembly as recited in claim 1 ; and
a substrate, wherein
the polarizing plate is bonded to a surface of the substrate on a side of the polarizing plate having the first protective film, with the transparent pressure sensitive adhesive layer being interposed therebetween.

10. A liquid crystal display device, comprising:
the polarizing plate assembly as recited in claim 1 ; and
a liquid crystal cell including a substrate, wherein
the polarizing plate is bonded to a surface of the substrate on a side of the polarizing plate having the first protective film, with the transparent pressure sensitive adhesive layer being interposed therebetween, and
a resolution of a display screen is not lower than 300 dpi.

11. The liquid crystal display device according to claim 10 , wherein
the liquid crystal cell is a normally black-type liquid crystal cell.

12. An organic electroluminescence display device, comprising:
the polarizing plate assembly as recited in claim 1 ; and
an organic electroluminescence display element including a substrate, wherein
the polarizing plate is bonded to a surface of the substrate on a side of the polarizing plate having the first protective film, with the transparent pressure sensitive adhesive layer being interposed therebetween, and
the first protective film is a phase retardation film, and an angle of a slow axis of the first protective film with respect to an absorption axis of the polarizing layer is 45°±10° or 135°±10°.

Assignees

• Sumitomo Chemical Co

Inventors

• Matsuno Kenji
• Inokuchi Yuuhei

Classifications

• G02B5/3033 Primary

  in the form of a thin sheet or foil, e.g. Polaroid · CPC title

• G02F1/133528

  Polarisers · CPC title

• B32B7/12

  using interposed adhesives or interposed materials with bonding properties · CPC title

• B32B27/306

  comprising vinyl acetate or vinyl alcohol (co)polymers · CPC title

• B32B2307/4026

  within the layer by addition of a colorant, e.g. pigments, dyes · CPC title