Polarizing plate for light emitting display apparatus having adhesive layers of specified modulus

Patent metadata

Field	Value
Publication number	US-11237311-B2
Application number	US-201815869866-A
Country	US
Kind code	B2
Filing date	Jan 12, 2018
Priority date	Jan 13, 2017
Publication date	Feb 1, 2022
Grant date	Feb 1, 2022

Abstract

A polarizing plate includes a polarizing film, a first adhesive layer or a bonding layer, a retardation layer, and a third adhesive layer, and includes: a UV absorber comprising an indole UV absorber, a phenylbenzotriazole UV absorber, and/or a triazine UV absorber, wherein the UV absorber has a maximum absorption wavelength of 370 nm or higher, the polarizing plate has a light transmittance of 5% or less in a wavelength range of about 400 nm to about 405 nm and a light transmittance of 35% or higher in a wavelength range of about 440 nm to about 450 nm, the first adhesive layer has a modulus of 1×105 Pa or higher at 80° C. and a modulus of 1×105 Pa or higher at 30° C., and the third adhesive layer has a modulus of 5×104 Pa to 1×106 Pa at 80° C. and a modulus of 1×105 Pa to 3×106 Pa at 30° C.

First claim

What is claimed is:

1. A polarizing plate for light emitting displays in which a polarizing film, a first adhesive layer or a bonding layer, a retardation layer, and a third adhesive layer are sequentially stacked, the polarizing plate comprising:
a UV absorber including at least one of an indole UV absorber, a phenylbenzotriazole UV absorber, and a triazine UV absorber, wherein:
the UV absorber has a maximum absorption wavelength of 370 nm or higher,
the polarizing plate has a light transmittance of 5% or less in a wavelength range of about 400 nm to about 405 nm and a light transmittance of 35% or higher in a wavelength range of about 440 nm to about 450 nm,
the first adhesive layer has a modulus of 5×10 4 Pa or higher at 80° C. and a modulus of 6×10 5 Pa or higher at 30° C.,
the third adhesive layer has a modulus of 3×10 5 Pa to 1×10 6 Pa at 80° C. and a modulus of 6×10 5 Pa to 3×10 6 Pa at 30° C.,
a modulus ratio of the third adhesive layer to the first adhesive layer at 80° C. ranges from 1:0.8 to 1:1.2,
the retardation layer is obtained by sequentially stacking a first retardation film, a second adhesive layer, and a second retardation film, and
the second adhesive layer has a modulus of 3×10 5 Pa to 1×10 6 Pa at 80° C. and a modulus of 6×10 5 Pa to 3×10 6 Pa at 30° C.

2. The polarizing plate as claimed in claim 1 , wherein the UV absorber is contained in at least one of the first adhesive layer and the third adhesive layer.

3. The polarizing plate as claimed in claim 1 , wherein the UV absorber is contained in at least one of the first adhesive layer, the second adhesive layer, and the third adhesive layer.

4. The polarizing plate as claimed in claim 1 , wherein the UV absorber has a maximum absorption wavelength of 380 nm to 420 nm.

5. The polarizing plate as claimed in claim 1 , wherein the UV absorber has an absorbance of 0.5 AU to 1.0 AU, as measured at a maximum absorption wavelength at a concentration of 10 mg/L in chloroform (per 1 cm path length).

6. The polarizing plate as claimed in claim 1 , wherein the UV absorber has a melting point of 200° C. or less.

7. The polarizing plate as claimed in claim 3 , wherein the UV absorber is present in an amount of about 0.1 wt % to about 5.0 wt % in at least one of the first adhesive layer, the second adhesive layer, and the third adhesive layer.

8. The polarizing plate as claimed in claim 1 , wherein the first retardation film has an Re of 100 nm to 220 nm at a wavelength of 550 nm, and the second retardation film has an Re of 225 nm to 350 nm at a wavelength of 550 nm.

9. The polarizing plate as claimed in claim 1 , wherein each of the first retardation film and the second retardation film includes at least one of a resin film, a liquid crystal film, and a liquid crystal coating layer.

10. The polarizing plate as claimed in claim 1 , wherein the second adhesive layer has a thickness of 1 μm to 80 μm.

11. The polarizing plate as claimed in claim 1 , wherein at least one of the first adhesive layer, the second adhesive layer, and the third adhesive layer is formed of a composition for adhesive layers including a copolymer of a monomer mixture including an alkyl group-containing (meth)acrylate, a hydroxyl group-containing (meth)acrylate, and a carboxylic acid group-containing monomer.

12. The polarizing plate as claimed in claim 11 , wherein the composition for adhesive layers includes at least one of a curing agent and a silane coupling agent.

13. The polarizing plate as claimed in claim 1 , wherein the polarizing film includes a polarizer, a first protective layer on one surface of the polarizer, and a second protective layer on another surface of the polarizer.

14. The polarizing plate as claimed in claim 1 , wherein the polarizing plate has a haze of 5% or less, as measured under at least one of the following conditions:
i) after being allowed to stand at 80° C. for 250 hours,
ii) after being allowed to stand at 60° C. and 90% RH for 250 hours.

15. The polarizing plate as claimed in claim 1 , wherein:
the polarizing plate has a sequential stack of the polarizing film, the first adhesive layer, the second retardation film, the second adhesive layer, the first retardation film, and the third adhesive layer,
the UV absorber is contained in the first adhesive layer or the third adhesive layer,
the first retardation film has an Re of 100 nm to 220 nm at a wavelength of 550 nm, and
the second retardation film has an Re of 225 nm to 350 nm at a wavelength of 550 nm.

16. A light emitting display comprising the polarizing plate according to claim 1 .

Assignees

• Samsung Sdi Co Ltd

Inventors

• Lee Seung Jun
• Jeong Woo Jin
• Suh Yoo Jin
• Cho Ha Yun
• Choi Han Joo
• Han In Cheon

Classifications

• H10K59/8791

  Arrangements for improving contrast, e.g. preventing reflection of ambient light · CPC title

• C09J11/00

  Features of adhesives not provided for in group C09J9/00, e.g. additives · CPC title

• G02B5/3041 Primary

  comprising multiple thin layers, e.g. multilayer stacks · CPC title

• G02B5/208

  for use with infrared or ultraviolet radiation, e.g. for separating visible light from infrared and/or ultraviolet radiation · CPC title

• G02B5/223

  containing organic substances, e.g. dyes, inks or pigments · CPC title