Polarizing plate and method for producing polarizing plate

Patent metadata

Field	Value
Publication number	US-10078163-B2
Application number	US-201515110851-A
Country	US
Kind code	B2
Filing date	Jan 22, 2015
Priority date	Jan 30, 2014
Publication date	Sep 18, 2018
Grant date	Sep 18, 2018

Abstract

The present invention is to provide a polarizing plate including an alignment layer applicable to various types of substrates, and having excellent light polarization properties. A polarizing plate 1 of the present invention includes an alignment layer 3, and a polarizing layer 4 disposed on the alignment layer 3, and containing an organic dye having lyotropic liquid crystallinity, wherein the organic dye in the polarizing, layer 4 is in a form of supramolecular aggregates, and the alignment layer 3 contains a cycloolefin based resin.

First claim

What is claimed is:

1. A polarizing plate comprising:
a substrate;
an alignment layer disposed on the substrate; and
a polarizing layer disposed on the alignment layer, and containing an organic dye having lyotropic liquid crystallinity,
wherein the organic dye in the polarizing layer is in a form of supramolecular aggregates,
wherein the alignment layer is formed of a coating film containing a cycloolefin based resin and has a thickness of 2 μm to 10 μm, and
wherein the alignment layer has a surface on which a rubbing treatment has been performed.

2. The polarizing plate according to claim 1 , wherein the cycloolefin based resin is amorphous.

3. The polarizing plate according to claim 1 , wherein the cycloolefin based resin is a norbornene based resin.

4. The polarizing plate according to claim 1 , wherein the alignment layer is substantially optically isotropic.

5. The polarizing plate according to claim 1 , wherein the substrate is a resin film containing a resin, and the resin has a glass transition temperature (Tg) of 180° C. or less.

6. The polarizing plate according to claim 1 , wherein the substrate has a surface having releasability.

7. A method for producing a polarizing plate, comprising:
a step of applying a first coating liquid containing a cycloolefin based resin on a substrate to form a first coating film;
a step of drying the first coating film to form a first dry coating film;
a step of performing a rubbing treatment on a surface of the first dry coating film to form an alignment layer having a thickness of 2 μm to 10 μm;
a step of applying a second coating liquid containing an organic dye on a surface of the alignment layer on which the rubbing treatment has been performed to form a second coating film; and
a step of drying the second coating film to form a second dry coating film as a polarizing layer.

Assignees

• Nitto Denko Corp

Inventors

• Asanoi Yoshiaki
• Okada Kazumasa
• Matsuda Shoichi
• Takemoto Hiroyuki

Classifications

• G02F2202/08

  glass transition temperature · CPC title

• B29D11/0073

  Optical laminates · CPC title

• G02B5/3016 Primary

  involving passive liquid crystal elements (optical properties of liquid crystals G02F1/0063; polarising elements associated with active liquid crystal devices G02F1/133528) · CPC title

• G02F1/133711

  by organic films, e.g. polymeric films · CPC title

• B29D11/00644

  polarizing · CPC title