Nitto-denko Corporation

Fumiko Nakano

Masayuki Satake

Makoto Kojima

Yuji Hotta

Yutaka Moroishi

Kohei Yano

Yuusuke Toyama

Tetsuo Inoue

Toshitsugu Hosokawa

Shinichi Inoue

Akiko Ogasawara

Yoshihide Kawaguchi

Michiharu Yamamoto

Masakazu Sugimoto

Keisuke Hirano

Kazumi Higashi

Takashi Tominaga

Akiko Tanaka

Mizue Nagata

Shigeru Fujita

Aimi Matsuura

Fumiaki Shirafuji

Tomoko Doi

A photocurable pressure-sensitive adhesive composition, a photocurable pressure-sensitive adhesive layer, and a photocurable pressure-sensitive adhesive sheet including a support and such a photocurable pressure-sensitive adhesive layer formed on at least one side of the support are provided. The photocurable pressure-sensitive adhesive composition can form an adhesive layer that has sufficient initial adhesive strength through the process of drying and cross-linking without having any adhesive protruding at normal temperatures and pressures, hardens easily with light irradiation, and has a high peeling resistance. The photocurable adhesive composition contains a graft polymer that graft-polymerizes a monomer containing a cyclic ether group to a (meth)acrylic polymer and a cationic photopolymerization initiator. The photocurable adhesive layer and the photocurable adhesive sheet are prepared by using said photocurable adhesive composition.

Photocurable adhesive composition, photocurable adhesive layer, and photocurable adhesive sheet

Provided are: an adhesive composition that is capable of providing an adhesive layer in which titanium-based nanoparticles are stably dispersed, an adhesive layer having more enhanced mechanical characteristics, excellent refractive index and excellent adhesive force, and an adhesive sheet or the like which uses the adhesive composition.

Adhesive composition, adhesive layer and adhesive sheet

A pressure-sensitive adhesive composition for an optical film of the present invention comprises 100 parts by weight of a (meth)acrylic polymer comprising 45 to 99.99% by weight of an alkyl (meth)acrylate monomer unit and 0.01 to 2% by weight of a tertiary amino group-containing monomer unit; and 0.01 to 2 parts by weight of a peroxide as a crosslinking agent. The pressure-sensitive adhesive composition can form an pressure-sensitive adhesive layer that has satisfactory reworkability such that optical films can be easily peeled from liquid crystal panels with no adhesive residue and also has satisfactory processability such that it can be worked without pressure-sensitive adhesive fouling or dropout.

Pressure-sensitive adhesive composition for optical film, pressure-sensitive adhesive layer for optical film, production method thereof, pressure-sensitive adhesive optical film and image display

An object of the invention is to provide a pressure-sensitive adhesive optical film-peeling method capable of easily detaching the pressure-sensitive adhesive optical film from a glass substrate with no damage to the glass substrate or no adhesive deposit on the glass substrate, and to provide a pressure-sensitive adhesive optical film suitable for use in such a peeling method. The invention is directed to a method for peeling a pressure-sensitive adhesive optical film from an optical film-carrying glass substrate including a glass substrate and the pressure-sensitive adhesive optical film bonded thereto, which includes: exposing the optical film-carrying glass substrate to an environment at a temperature of 40 to 98&#xb0; C. and a relative humidity of 60 to 99% for three minutes or more; and then peeling the pressure-sensitive adhesive optical film from the glass substrate under the environment.

Method for peeling pressure-sensitive adhesive optical film, and pressure-sensitive adhesive optical film

This invention provides a pressure-sensitive adhesive composition that exhibits excellent pressure-sensitive adhesive properties after crosslinking treatment, does not cause lifting or lifting upon heat treatment or treatment under high-humidity conditions particularly even in the case of a pressure-sensitive adhesive layer having a reduced layer thickness, and has excellent durability. A pressure-sensitive adhesive layer formed using the pressure-sensitive adhesive composition, and a process for producing the same are also provided. Further, an optical member with pressure-sensitive adhesive comprising the pressure-sensitive adhesive layer and an image display using the same are provided. The pressure-sensitive adhesive composition is characterized by comprising 100 parts by weight of an (meth)acrylic polymer and 0.02 to 2 parts by weight of a peroxide, and 0.02 to 2 parts by weight of an isocyanate crosslinking agent, the (meth)acrylic polymer comprising as monomer units 50 to 98% by weight of an (meth)acrylic monomer represented by general formula CH&#x2550;C(R)COOR, wherein Rrepresents hydrogen or a methyl group and Rrepresents an alkyl group having 2 to 14 carbon atoms, and 0.1 to 35% by weight of a nitrogen-containing monomer.

Pressure-sensitive adhesive composition, pressure-sensitive adhesive layer, process for producing the pressure-sensitive adhesive layer, and optical member with pressure-sensitive adhesive

An object of the present invention is to provide a pressure sensitive adhesive composition for an optical member, which is excellent in coating property because of low viscosity, can reduce an amount of an organic solvent used, and can form a pressure sensitive adhesive layer excellent in durability and having high surface uniformity. The present invention relates to a pressure sensitive adhesive composition for an optical member, which comprises a (meth)acrylic polymer, a C6 to C9 hydrocarbon-based solvent (A), and a high-boiling highly solubilizing solvent (B) having a boiling point higher than that of the above hydrocarbon-based solvent and having a higher ability to solubilize the (meth)acrylic polymer than that of the above hydrocarbon-based solvent, wherein a content of the hydrocarbon-based solvent (A) is 20 to 60 wt % based on the total amount of the solvents, and a ratio of the content (wt %) of the hydrocarbon-based solvent (A) to the content (wt %) of the high-boiling highly solubilizing solvent (B) (high-boiling highly solubilizing solvent (B)/hydrocarbon-based solvent (A)) is 0.05 to 4.

Pressure sensitive adhesive composition for optical members, pressure sensitive adhesive layer for optical members, pressure sensitive adhesive optical member and image display

Provided are a pressure sensitive adhesive composition for optical members and a pressure sensitive adhesive composition for optical members. The pressure sensitive adhesive composition for optical members according to the present invention comprises 100 parts by weight of an acrylic polymer (A) having a weight-average molecular weight of 500,000 or more, containing at least 50 wt % alkyl (meth)acrylate having an alkyl group with 5 or more carbon atoms and 0.2 to 2 wt % unsaturated carboxylic acid as the monomer unit, 0.1 to 4 parts by weight of an acrylic polymer (B) having a weight-average molecular weight of 2,000 to 50,000, containing at least 70 wt % alkyl (meth)acrylate and 1 to 7 wt % unsaturated carboxylic acid as the monomer unit and having a higher carboxylic acid equivalent than that of the acrylic polymer (A), 0.01 to 1 part by weight of a silane coupling agent, and a crosslinking agent.

Provided herein is a pressure sensitive adhesive for an optical film comprising: 100 parts by weight of a (meth)acrylic-based polymer (A) including an alkyl (meth)acrylate (a1) and a (meth)acrylic-based monomer containing a hydroxyl group (a2), as a copolymerizable component, in content in the range of from 0.01 to 5 parts by weight relative to 100 parts by weight of the alkyl (meth)acrylate (a1); 0.02 to 2 parts by weight of a peroxide (B); and 0.001 to 2 parts by weight of an isocyanate-based compound (C), the contents of the peroxide (B) and the isocyanate-based compound (C) being values relative to 100 parts by weight of the (meth)acrylic-based polymer (A).

Adhesive of (meth)acrylate polymer, peroxide and isocyanate laminated on optical film

It is an object of the invention to provide a pressure sensitive adhesive for an optical film with which a pressure sensitive adhesive type optical film capable of suppressing bowing and light leakage caused by a stress accompanying a dimensional change of members such as an optical film, high in durability, excellent in handling ability in an aspect of a fabrication process thereof and good in quality can be obtained. There is provided a pressure sensitive adhesive for an optical film comprising: 100 parts by weight of a (meth)acrylic-based polymer (A) including an alkyl (meth)acrylate (a1) and a (meth)acrylic-based monomer containing a hydroxyl group (a2), as a copolymerizable component, in content in the range of from 0.01 to 5 parts by weight relative to 100 parts by weight of the alkyl (meth)acrylate (a1); 0.02 to 2 parts by weight of a peroxide (B); and 0.001 to 2 parts by weight of an isocyanate-based compound (C), the contents of the peroxide (B) and the isocyanate-based compound (C) being values relative to 100 parts by weight of the (meth)acrylic-based polymer (A).

Pressure sensitive adhesives for optical film, manufacturing methods for pressure sensitive adhesive layer for optical film, pressure sensitive adhesive layers for optical film, pressure sensitive adhesion type optical films and image displays

The present invention provides a pressure sensitive adhesive composition for optical members, which is excellent in durability, re-releasability and stress relaxation, as well as a pressure sensitive adhesive composition for optical members, which hardly increases adhesion after storage for a long time and does not leave a residual adhesive on glass upon disposal or repair. The pressure sensitive adhesive composition for optical members according to the present invention comprises 100 parts by weight of an acrylic polymer (A) having a weight-average molecular weight of 500,000 or more, containing at least 50 wt % alkyl (meth)acrylate having an alkyl group with 5 or more carbon atoms and 0.2 to 2 wt % unsaturated carboxylic acid as the monomer unit, 0.1 to 4 parts by weight of an acrylic polymer (B) having a weight-average molecular weight of 2,000 to 50,000, containing at least 70 wt % alkyl(meth)acrylate and 1 to 7 wt % unsaturated carboxylic acid as the monomer unit and having a higher carboxylic acid equivalent than that of the acrylic polymer (A), 0.01 to 1 part by weight of a silane coupling agent, and a crosslinking agent.

The object of the present invention is to produce a polymer, which is free from the troubles of the coloration and the decrease in the mechanical properties of molded articles (films, etc.), crosslinkage failure, migration (stain) or the like, by the living radical polymerization method wherein the content of impurities consisting of a transition metal and its ligand employed as a polymerization activator is reduced. A process for producing a polymer is described, comprising: a) the step of performing a polymerization reaction by using a monomer, a transition metal and its ligand and a polymerization initiator to form a polymer; and b) the step of eliminating the transition metal and its ligand contained in the polymer under the condition of a viscosity of 100 Pa&middot;s or below, wherein the step b comprises: b1) the former step of eliminating the transition metal and its ligand insoluble in the polymer; and b2) the latter step of eliminating the transition metal and its ligand dissolved in the polymer.

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Ibaraki, Japan

Fumiko Nakano