Teijin Limited

Other

Hideaki Nitta

Kaoru Iwata

Utami Yonemura

Takeshi Sasaki

Takashi Shiro

Kiyonari Hashidzume

Masaki Takeuchi

Yutaka Taketani

Michio Yamaura

A cyclic olefin polymer having a small content of a catalyst residue, a production process for the same and use of the same as an optical material. Catalysts used for polymerization and/or hydrogenation reaction for forming the cyclic olefin polymer are decomposed efficiently by adding at least one compound selected from the group consisting of an &agr;-oxyacid and &bgr;-oxyacid having one hydroxyl group and one carboxyl group in the molecule and derivatives obtained by substituting hydroxyl group thereof by an alkoxyl group, and the decomposition products are removed by rendering them insoluble in a reaction solvent used for the polymerization and/or hydrogenation reaction and precipitating them efficiently.

Cyclic olefin polymer containing little catalyst residue

Process for producing a hydrogenated &agr;-olefin-dicyclopentadiene copolymer. The process includes a step of distilling of unreacted dicyclopentadiene or tetrahydrodicyclopentadiene which is a hydrogenated product of unreacted dicyclopentadiene from a mixture containing &agr;-olefin-dicyclopentadiene copolymer or its hydrogenated product in the presence of a high-boiling hydrocarbon solvent having a boiling point of 195 to 300&deg; C. and an ignition point of 260&deg; C. or more. Method for melt molding the hydrogenated &agr;-olefin-dicyclopentadiene copolymer is also proposed.

Process for producing hydrogenated &agr;-olefin-dicyclopentadiene copolymer, method for molding the same and optical material

&agr;-olefin-cycloolefin copolymers and process for their production

An optically isotropic film of an aromatic polyethersulfone, which is useful as a substrate for a liquid crystal display device, and an optically anisotropic, uniaxially oriented film of an aromatic polyethersulfone, which is useful as a phase difference plate for a liquid crystal display device. The optically isotropic film is produced by casting an aromatic polyethersulfone solution composition comprising 15 to 40 parts by weight of a solvent which contains at least 60% by weight of 1,3-dioxolane and can dissolve an aromatic polyethersulfone and 10 parts by weight of the aromatic polyethersulfone, on a substrate, and heating the cast solution composition containing a solvent to evaporate the solvent off.

Film of aromatic polyethersulfone, process for the production thereof,

Film of aromatic polyethersulfone process for the production thereof and

The present invention is to provide polycarbonate film excellent in optical properties such as high transparency and a process for producing it. The present invention relates to polycarbonate film having a specific retardation values, and a process for producing polycarbonate film by casting a dope onto a support and evaporating the solvent with heat wherein the dope is prepared by dissolving 10 parts by weight of polycarbonate resin in 30 to 150 parts by weight of the solvent mixture which contains more than 60% by weight of dioxolane.

Polycarbonate film for optical purposes and a production process thereof

The present invention is to provide a polycarbonate film excellent in optical properties such as high transparency and a process for producing it. The present invention relates to a polycarbonate film having a specific retardation value, and a process for producing a polycarbonate film by casting a dope onto a support and evaporating the solvent with heat wherein the dope is prepared by dissolving 10 parts by weight of polycarbonate resin in 30 to 150 parts by weight of the solvent mixture which contains more than 60% by weight of dioxolane.

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Hino, Japan

Hideaki Nitta