Liquid crystal display device

Patent metadata

Field	Value
Publication number	US-9645438-B2
Application number	US-201514924879-A
Country	US
Kind code	B2
Filing date	Oct 28, 2015
Priority date	May 1, 2013
Publication date	May 9, 2017
Grant date	May 9, 2017

Abstract

Provided is a liquid crystal display device including a liquid crystal cell having a liquid crystal layer between two glass substrates, a front-side polarizing plate provided on a front side of the liquid crystal cell, a rear polarizer provided on a rear side of the liquid crystal cell, and a backlight provided on a rear side of the rear polarizer, in which the front-side polarizing plate has a first protective film, a polarizer, and a second protective film in this order from a surface side opposite to the liquid crystal cell, the first protective film in the front-side polarizing plate is a film including a polyester resin or a polycarbonate resin as a main component, an Re of the first protective film is 3000 nm or higher, an equilibrium moisture content of the second protective film at 25° C. and a relative humidity of 60% is in a range of 1% to 3%, and in the second protective film, a contractile force in a direction orthogonal to an absorption axis of the polarizer is 1.3 times or higher a contractile force in a direction parallel to the absorption axis of the polarizer which is capable of suppressing luminance unevenness at the four corners of the panel when a backlight is turned on after the liquid crystal display device has been stored in a hot and humid environment.

First claim

What is claimed is:

1. A liquid crystal display device comprising:
a liquid crystal cell having a liquid crystal layer between two glass substrates;
a front-side polarizing plate provided on a front side of the liquid crystal cell;
a rear polarizer provided on a rear side of the liquid crystal cell; and
a backlight provided on a rear side of the rear polarizer,
wherein the front-side polarizing plate has a first protective film, a polarizer, and a second protective film in this order from a surface side opposite to the liquid crystal cell,
the first protective film in the front-side polarizing plate is a film including a polyester resin or a polycarbonate resin as a main component,
a retardation Re in an in-plane direction of the first protective film in the front-side polarizing plate is 3000 nm or higher,
an equilibrium moisture content of the second protective film in the front-side polarizing plate at 25° C. and a relative humidity of 60% is in a range of 1% to 3%, and
in the second protective film in the front-side polarizing plate, a contractile force in a direction orthogonal to an absorption axis of the polarizer is 1.3 times or higher a contractile force in a direction parallel to the absorption axis of the polarizer.

2. The liquid crystal display device according to claim 1 ,
wherein, in the first protective film in the front-side polarizing plate, a modulus of elasticity in the direction orthogonal to the absorption axis of the polarizer is in a range of 1.5 times to 4 times the modulus of elasticity in the direction parallel to the absorption direction of the polarizer.

3. The liquid crystal display device according to claim 1 ,
wherein the second protective film in the front-side polarizing plate is a film including a (meth)acrylic resin or a cellulose acylate resin.

4. The liquid crystal display device according to claim 1 ,
wherein, in the second protective film in the front-side polarizing plate, the contractile force in the direction orthogonal to the absorption axis of the polarizer is 1.4 times or higher the contractile force in the direction parallel to the absorption axis of the polarizer.

5. The liquid crystal display device according to claim 1 ,
wherein, in the rear polarizer, a photoelastic coefficient of a protective film on a liquid crystal cell side is 11×10 −12 /Pa or lower.

6. The liquid crystal display device according to claim 1 ,
wherein the rear polarizer has a first protective film, a polarizer, and a second protective film in this order from the surface side opposite to the liquid crystal cell,
the first protective film in the rear polarizer is a film including a polyester resin or a polycarbonate resin as a main component,
a retardation Re in an in-plane direction of the first protective film in the rear polarizer is 3000 nm or higher,
the second protective film in the rear polarizer is a film including a (meth)acrylic resin or a cellulose acylate rein, and
in the second protective film in the rear polarizer, a contractile force in the direction orthogonal to the absorption axis of the polarizer is 1.3 times or higher a contractile force in the direction parallel to an absorption-axis direction of the polarizer.

7. The liquid crystal display device according to claim 1 ,
wherein thicknesses of the two glass substrates configuring the liquid crystal cell in the liquid crystal display device are respectively 0.5 mm or smaller.

Assignees

• Fujifilm Corp

Inventors

• Sekiguchi Megumi
• Furukawa Hiromichi
• Yamada Naoyoshi

Classifications

• G02F2201/54

  Arrangements for reducing warping-twist · CPC title

• G02F2001/133562

  Physics · mapped topic

• G02F2001/133567

  Physics · mapped topic

• G02B5/305

  including organic materials, e.g. polymeric layers · CPC title

• G02F2001/133302

  Physics · mapped topic