One-side-protected polarizing film, pressure-sensitive-adhesive-layer-attached polarizing film, image display device, and method for continuously producing same

Patent metadata

Field	Value
Publication number	US-10067268-B2
Application number	US-201515514710-A
Country	US
Kind code	B2
Filing date	Sep 29, 2015
Priority date	Sep 30, 2014
Publication date	Sep 4, 2018
Grant date	Sep 4, 2018

Abstract

A one-side-protected polarizing film having a transparent protective film on only one surface of a polarizer, wherein: the polarizer contains a polyvinyl alcohol-based resin, has a thickness of 10 μm or less, and is designed to have a single-body transmittance T and a polarization degree P representing optical properties satisfying the condition of the following formula: P>−(100.929T−42.4−1)×100 (provided that T<42.3) or P≥99.9 (provided that T≥42.3); and the other surface of the polarizer has a transparent layer thereon satisfying formula 1 (F≥3) and formula 2 (C≥e−0.7F), given that the thickness thereof is F (μm) and the compressive elastic modulus thereof at 80° C. is C (GPa). Even when the polarizer has prescribed optical properties and the thickness is 10 μm or less, this one-side-protected polarizing film is capable of suppressing through cracks and nano-slits.

First claim

The invention claimed is:

1. A one-side-protected polarizing film, comprising:
a polarizer;
a transparent protective film provided on only one surface of the polarizer; and
a transparent layer provided directly on another surface of the polarizer, wherein
the polarizer comprises a polyvinyl alcohol-based resin, has a thickness of 10 μm or less, and is designed to have a single-body transmittance T and a polarization degree P representing optical properties satisfying the condition of the following formula: P>−(10 0.929T−42.4 −1)×100 (provided that T<42.3) or P≥99.9 (provided that T≥42.3), and
the transparent layer has a thickness F (μm) and an 80° C. compressive elastic modulus C (GPa) satisfying formula 1: F≥3 and formula 2: C≥e −0.7F .

2. The one-side-protected polarizing film according to claim 1 , wherein the transparent layer is a coating layer.

3. The one-side-protected polarizing film according to claim 1 , wherein the transparent layer has an 80° C. compressive elastic modulus of 0.1 GPa or more.

4. The one-side-protected polarizing film according to claim 1 , wherein the transparent layer is a product obtained by curing a curable, layer-forming material containing a curable component.

5. The one-side-protected polarizing film according to claim 1 , wherein the polarizer contains 25% by weight or less of boric acid based on the total weight of the polarizer.

6. A method for producing the one-side-protected polarizing film according to claim 1 , comprising:
the polarizer;
the transparent protective film provided on only one surface of the polarizer; and
the transparent layer provided directly on another surface of the polarizer, wherein
the polarizer comprises a polyvinyl alcohol-based resin, has a thickness of 10 μm or less, and is designed to have a single-body transmittance T and a polarization degree P representing optical properties satisfying the condition of the following formula: P>−(10 0.929T−42.4 −1)×100 (provided that T<42.3) or P≥99.9 (provided that T≥42.3),
the transparent layer has a thickness F (μm) and an 80° C. compressive elastic modulus C (GPa) satisfying formula 1: F≥3 and formula 2: C≥e −0.7F , and
the transparent layer is provided by applying directly a transparent layer-forming material on another surface of the polarizer.

7. A pressure-sensitive-adhesive-layer-attached polarizing film comprising: the one-side-protected polarizing film according to claim 1 ; and a pressure-sensitive adhesive layer.

8. The pressure-sensitive-adhesive-layer-attached polarizing film according to claim 7 , wherein the pressure-sensitive adhesive layer is provided on the transparent layer of the one-side-protected polarizing film.

9. The pressure-sensitive-adhesive-layer-attached polarizing film according to claim 7 , wherein the pressure-sensitive adhesive layer is provided on the transparent protective film of the one-side-protected polarizing film.

10. The pressure-sensitive-adhesive-layer-attached polarizing film according to claim 7 , further comprising a separator provided on the pressure-sensitive adhesive layer.

11. The pressure-sensitive-adhesive-layer-attached polarizing film according to claim 10 , which is in the form of a roll.

12. An image display device comprising the one-side-protected polarizing film according to claim 1 .

13. An image display device comprising the pressure-sensitive-adhesive-layer-attached polarizing film according to claim 7 .

14. A method for continuously producing an image display device, the method comprising the steps of:
unwinding the pressure-sensitive-adhesive-layer-attached polarizing film from the roll of the pressure-sensitive-adhesive-adhesive-layer-attached polarizing film according to claim 11 ;
feeding the pressure-sensitive-adhesive-layer-attached polarizing film with the separator; and
continuously bonding the pressure-sensitive-adhesive-layer-attached polarizing film to a surface of an image display panel with the pressure-sensitive adhesive layer interposed therebetween.

Assignees

• Nitto Denko Corp

Inventors

• Mita Satoshi
• Ueno Tomonori
• Motegi Yusuke
• Ishihara Yasutaka
• Nakato Ayami
• Kishi Atsushi

Classifications

• C09J2201/606

  Chemistry & Metallurgy · mapped topic

• C09J2429/006

  in the substrate · CPC title

• C09D129/04

  Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids · CPC title

• G02F1/133528

  Polarisers · CPC title

• C09J2203/326

  for bonding electronic components such as wafers, chips or semiconductors · CPC title