Nitto-denko Corporation

Kentaro Ikeshima

Shusaku Goto

Minoru Miyatake

Atsushi Kishi

Tomonori Ueno

Yuuki Nakano

Satoshi Mita

Osamu Kaneko

Yusuke Motegi

Yuki Nakano

Nobuyuki Haida

Yoshifumi Yamamoto

Emi Miyai

Toshiki Omine

A surface-protective film attached polarizing film is disclosed which includes a polarizing film (A) having a thickness of 100 &#x3bc;m or less, and a surface-protective film (B) provided on at least one surface of the polarizing film (A), wherein the polarizing film (A) comprises a polarizer, and a protective film provided on at least one surface of the polarizer, the polarizer comprises a polyvinyl alcohol-based resin and has a thickness of 10 &#x3bc;m or less, the polarizing film (A) has a width W, the surface-protective film (B) has a width W, a difference between the widths Wand W(W&#x2212;W) is 3 mm or more, and a peel strength of the surface-protective film (B) to the polarizing film (A) is 0.2 N/25-mm or less. The surface-protective film-attached polarizing film allows to be restrained the polarizing film from being broken, when the surface-protective film is peeled from the polarizing film.

Surface-protective film-attached polarizing film, and method for producing polarizing film

There is provided a polarizing film that is excellent in optical characteristics, and is excellent in durability and water resistance. A polarizing film according to an embodiment of the present invention includes a polyvinyl alcohol-based resin film having a thickness of 10 &#x3bc;m or less. The polyvinyl alcohol-based resin film has an iodine concentration of 6.0 wt % or less; and the polarizing film has a cross-linking index defined by the below-indicated equation of from 100 to 200: (Cross-linking index)=(Iodine concentration in film)&#xd7;(Boric acid concentration in film).

Polyvinyl alcohol based polarizing film containing iodine and boric acid

A method for producing a polarizing film includes (1) preparing a laminate (a) which includes a carrier film and a polarizer with a thickness of 10 &#x3bc;m or less formed on one surface of the carrier film and contains a polyvinyl alcohol-based resin; (2) peeling off the carrier film from the laminate (a); and (3) applying a liquid material to a side of the laminate (a) from which the carrier film has been peeled off and then solidifying or curing the liquid material to form a transparent resin layer with a thickness of 0.2 &#x3bc;m or more, wherein the liquid material contains a resin component or a curable component capable of forming a resin layer. This production method enables the achievement of a polarizing film which is able to have satisfactory durability in a heated environment even in cases where a thin polarizer is used therefor.

Method for producing polarizing film

An optical display device which includes a display panel, and at least one polarizing film including a polyvinyl alcohol-based resin layer disposed on a viewing side with respect to the display panel, and having an optical arrangement forming a cross-Nicol relationship with regard to polarized light entering the polarizing film from the side of the display panel. The polarizing film is produced to have a thickness of 10 &#x3bc;m or less, by a method comprising the steps of: forming a polyvinyl alcohol-based resin layer on a resin substrate; stretching the polyvinyl alcohol-based resin layer integrally with the resin substrate; and dyeing the polyvinyl alcohol-based resin layer using a dichroic material. The polarizing film is disposed in the optical display device in a state in which a surface of the polarizing film as a contact surface with the resin substrate during the production thereof is oriented toward a side opposite to the display panel.

Optical display device

A method of manufacturing a polarizing plate according to an embodiment of the present invention includes: stretching and dyeing a laminate including a resin substrate having a long shape and a polyvinyl alcohol-based resin layer formed on one side of the resin substrate, to thereby produce a polarizing film on the resin substrate; laminating an optically functional film on a side of the polarizing film of the laminate, to thereby produce an optically functional film laminate; and cutting widthwise direction end portions of the optically functional film laminate. The cut portions include the resin substrate, the polarizing film, and the optically functional film.

Method of manufacturing polarizing plate

A method of manufacturing a polarizing plate according to an embodiment of the present invention includes: stretching and dyeing a laminate having a resin substrate and a polyvinyl alcohol-based resin layer formed on at least one side of the resin substrate to produce a polarizing film on the resin substrate; laminating an optically functional film on the laminate on a polarizing film side to produce an optically functional film laminate; and peeling the resin substrate from the optically functional film laminate. The peeling is performed so that an angle &#x3b1; formed between a surface of the optically functional film laminate immediately before the peeling and a peeling direction of the resin substrate is smaller than an angle &#x3b2; formed between the surface of the optically functional film laminate immediately before the peeling and a peeling direction of the polarizing film.

Growing community of inventors

Ibaraki, Japan

Kentaro Ikeshima