IP Library Granted Patent US 7,674,518
Granted Patent B2
US 7,674,518 · App. 11/794,398 · Granted Mar 9, 2010

Polyvinyl alcohol film and polarizing film and polarizing plate using the same

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Quick Facts
Patent No.
US 7,674,518
App. No.
11/794,398
Granted
Mar 9, 2010
Kind
B2
Abstract

The present invention provides a polyvinyl alcohol film having a correlation length of 200 nm or less, the correlation length being derived from the result of light scattering measurement using a He—Ne laser having a wavelength of 633 nm as a light source.

Claims (10)

1. A polyvinyl alcohol film comprising a polyvinyl alcohol-based resin saponified at 99 to 100% by mol, which has a correlation length of 200 nm or less, in which the correlation length is derived from the result of light scattering measurement using a He—Ne laser having a wavelength of 633 nm as a light source, a content of fatty acid having 14 or more carbon atoms present in the film is from 0.1 to 40% by weight relative to the content of fatty acids having 10 or more carbon atoms, and a complete dissolution temperature of 65° or higher.

2. The polyvinyl alcohol film according to claim 1 , wherein a content of fatty acid having 10 or more carbon atoms present in the film is from 1 to 100 ppm.

3. The polyvinyl alcohol film according to claim 2 , wherein the fatty acid having 10 or more carbon atoms include lauric acid.

4. The polyvinyl alcohol film according to claim 2 , which contains a surfactant containing fatty acid having 10 or more carbon atoms in an amount of 1 to 10% by weight.

5. The polyvinyl alcohol film according to claim 1 , which contains a polyvinyl alcohol resin having a weight-average molecular weight of 140,000 to 260,000.

6. The polyvinyl alcohol film according to claim 1 , which has a film thickness of from 30 to 70 μm.

7. The polyvinyl alcohol film according to claim 1 , which has a film width of 3 m or more.

8. The polyvinyl alcohol film according to claim 1 , which has a film length of 4000 m or more.

9. A polarizing film formed from the polyvinyl alcohol film according to claim 1 .

10. A polarizing plate comprising the polarizing film according to claim 9 and a protective film provided on at least one surface of the above polarizing film.

Assignments (5)
MERGER Recorded Jun 12, 2019
From: THE NIPPON SYNTHETIC CHEMICAL INDUSTRY CO., LTD.
To: MITSUBISHI CHEMICAL CORPORATION
Reel/Frame 049441/0841 →
CHANGE OF ADDRESS Recorded Aug 30, 2018
From: THE NIPPON SYNTHETIC CHEMICAL INDUSTRY CO., LTD.
To: THE NIPPON SYNTHETIC CHEMICAL INDUSTRY CO., LTD.
Reel/Frame 046980/0539 →
CHANGE OF ADDRESS Recorded Aug 21, 2018
From: THE NIPPON SYNTHETIC CHEMICAL INDUSTRY CO., LTD.
To: THE NIPPON SYNTHETIC CHEMICAL INDUSTRY CO., LTD.
Reel/Frame 047520/0917 →
CHANGE OF NAME Recorded Oct 7, 2010
From: NIPPON SYNTHETIC CHEMICAL INDUSTRY CO., LTD., THE
To: NIPPON SYNTHETIC CHEMICAL INDUSTRY CO., LTD., THE
Reel/Frame 025119/0342 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 27, 2007
From: HAYAKAWA, SEIICHIROU; KITAMURA, SYUICHI; NISHIMOTO, YUKARI; CHIGAMI, AKIHIKO
To: NIPPON SYNTHETIC CHEMICAL INDUSTRY CO. LTD., THE
Reel/Frame 019534/0942 →