Nitto-denko Corporation

Satoshi Mita

Atsushi Kishi

Tomonori Ueno

Yusuke Motegi

Jingfan Xu

Masayuki Okamoto

Kentaro Ikeshima

Tetsuro Ikeda

Yoshimi Konno

Taiyan Jiang

Minoru Miyatake

Yasutaka Ishihara

Emi Miyai

Toshiki Omine

Ayami Nakato

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

The present invention pertains to a one-side-protected polarizing film having a protective film or films on only one surface of a polarizer, wherein: the polarizer contains a polyvinyl alcohol-based resin, 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&#x3e;&#x2212;(10&#x2212;1)&#xd7;100 (provided that T&#x3c;42.3) or P&#x2265;99.9 (provided that T&#x2265;42.3), and the polarizer and a transparent resin layer have a thickness X (&#x3bc;m) and a thickness Y (&#x3bc;m), respectively, satisfying X&#x2264;12, Y&#x2264;15, and 0.15&#x2264;(Y/X)&#x2264;3. Even when the thin-type polarizer has prescribed optical properties, this one-side-protected polarizing film is capable of suppressing the occurrence of through cracks, nano-slit-induced defects and curling.

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

A polarizing film is disclosed including a polarizer having a thickness of 10 &#x3bc;m or less, and a transparent resin layer on at least one surface of the polarizer,

Polarizing film, pressure-sensitive-adhesive-layer-attached polarizing film, method for producing polarizing film, and image display device

A polarizing film, wherein transparent protective films are laid, respectively, on/over both surfaces of a polarizer to interpose an adhesive layer (a) and an adhesive layer (b), respectively, between both the surfaces and the transparent protective films. The adhesive layer (a) has a glass transition temperature of &#x2212;60&#xb0; C. or higher and lower than 40&#xb0; C. The adhesive layer (b) has a glass transition temperature of 40&#xb0; C. or higher. The adhesive layer (a) is a layer formed in the form of a cured product layer yielded by radiating an active energy ray to an active-energy-ray-curable adhesive composition (a). The active-energy-ray-curable adhesive composition (a) comprises at least one or more radical polymerizable compounds, and when a total amount of the radical polymerizable compound(s) is defined as 100% by weight, one or more alkyl (meth)acrylates (A) (each) having 10 to 20 carbon atoms are comprised in a proportion of 15% or more by weight.

Polarizing film, method for producing same, optical film, and image display device

A polarizer according to the patent invention is configured to contain boric acid and a polyvinyl alcohol-based resin, to have a thickness of 10 &#x3bc;m or less, and to have an optical property satisfying the condition represented by the expression: P&#x3e;&#x2212;(10&#x2212;1)&#xd7;100 (when T&#x3c;42.3) or P&#x2265;99.9 (when T&#x2265;42.3), wherein T represents the single-body transmittance and P represents the polarization degree. In addition, a boric acid content (a) measured from one side of the polarizer, the one side to be provided with the pressure-sensitive adhesive layer, is less than a boric acid content (b) measured from the other side. The polarizer according to the patent invention can reduce defects due to through cracks and nano-slits even when the polarizer has predetermined optical properties and a thickness of 10 &#x3bc;m or less.

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

A polarizing film, wherein transparent protective films are laid, respectively, on/over both surfaces of a polarizer to interpose an adhesive layer (a) and an adhesive layer (b), respectively, between both surfaces of a polarizer, and transparent protective films. The adhesive layer (a) on/over one of both the surfaces has a glass transition temperature of &#x2212;60&#xb0; C. or higher and lower than 40&#xb0; C. The adhesive layer (b) on/over the other surface has a glass transition temperature of 40&#xb0; C. or higher. The adhesive layer (a) is a layer formed in the form of a cured product layer yielded by radiating an active energy ray to an active-energy-ray-curable adhesive composition (a). The active-energy-ray-curable adhesive composition (a) comprises, as radical polymerizable compounds, a component A having a logPow of &#x2212;2 to 2, and a component B having a logPow more than 7, these logPow values being each an octanol/water distribution coefficient.

The present invention pertains to a polarizing film having a transparent resin layer on at least one side of a polarizer containing a polyvinyl alcohol-based resin, wherein the transparent resin layer has a thickness of 0.2 &#x3bc;m or more and is formed from a layer-forming material containing a polyvinyl alcohol-based resin having a saponification degree of 96 mol % or more, and wherein the combined total content of sodium acetate and potassium acetate contained in the transparent resin layer is less than 1 wt %. This polarizing film has crack-resistant properties, and can minimize degradation of the optical characteristics in a heating and humidifying test.

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

The present invention pertains to a polarizing film having a transparent layer on at least one surface of a polarizer, wherein: the polarizer contains a polyvinyl alcohol-based resin and has a thickness of 15 &#x3bc;m or less; the transparent layer-side of the polarizer has a compatible layer thereon having compatibility with the transparent layer; and the thickness A of the polarizer and the thickness B of the compatible layer satisfy the general formula (100&#xd7;B/A)&#x2265;1. This polarizing film has crack resistance and suppresses changes in the dimensions of the polarizer.

Polarizing film, pressure-sensitive-adhesive-layer-attached polarizing film, and image display device

The present invention pertains to 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 &#x3bc;m 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&#x3e;&#x2212;(10&#x2212;1)&#xd7;100 (provided that T&#x3c;42.3) or P&#x2265;99.9 (provided that T&#x2265;42.3); and the other surface of the polarizer has a transparent layer having a compressive elastic modulus at 80&#xb0; C. of 0.1 GPa or more. Even when the polarizer has prescribed optical properties and the thickness is 10 &#x3bc;m or less, this one-side-protected polarizing film is capable of suppressing the occurrence of through cracks and nano-slits.

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

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 &#x3bc;m 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&#x3e;&#x2212;(10&#x2212;1)&#xd7;100 (provided that T&#x3c;42.3) or P&#x2265;99.9 (provided that T&#x2265;42.3); and the other surface of the polarizer has a transparent layer thereon satisfying formula 1 (F&#x2265;3) and formula 2 (C&#x2265;e), given that the thickness thereof is F (&#x3bc;m) and the compressive elastic modulus thereof at 80&#xb0; C. is C (GPa). Even when the polarizer has prescribed optical properties and the thickness is 10 &#x3bc;m or less, this one-side-protected polarizing film is capable of suppressing through cracks and nano-slits.

The present invention pertains to 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 &#x3bc;m 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&#x3e;&#x2212;(10&#x2212;1)&#xd7;100 (provided that T&#x3c;42.3) or P&#x2265;99.9 (provided that T&#x2265;42.3); and the other surface of the polarizer has a transparent resin layer having a thickness of 0.2 &#x3bc;m or more and formed from a layer-forming material including a polyvinyl alcohol-based resin. Even when the polarizer has prescribed optical properties and the thickness is 10 &#x3bc;m or less, this one-side-protected polarizing film is capable of suppressing the occurrence of through cracks and nano-slits.

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

Growing community of inventors

Ibaraki, Japan

Satoshi Mita