Nippon Telegraph and Telephone Corporation

Jsr Corporation

Tokyo Institute of Technology

Shinji Ando

Shigekuni Sasaki

Fumio Yamamoto

Toru Matsuura

Yasuyuki Inoue

Takashi Sawada

Toshiaki Tamamura

Yasuko Maruo

Tohru Matsuura

Shinsuke Matsui

Yasuhiro Nakamura

Mitsuru Ueda

Hideaki Takase

Fusao Shimokawa

Yuichi Eriyama

Keisuke Kuriyama

Shiro Nishi

Toshihiro Ichino

Shinji Koike

Shuichi Sugawara

Jin-gang Liu

Yuzi Shibasaki

Miwa Ariyuki

It is provided for a resin composition including (A) at least one polyamic acid having the structure represented by the following formula (1): wherein Ris independently an alkyl group having 1 to 3 carbon atoms or a cyano group; a is independently an integer of 0 to 4; R is a tetravalent organic group; n is an integer of 1 to 4; and m is an integer of 1 to 100,000, and (E) an organic solvent.

Resin composition, cured product and optical parts

An optical waveplate includes a polyimide with a film thickness of 20 .mu.m or less.

Optical waveplate, method of manufacturing the same, and waveguide

A method for preparing aromatic compounds including 1,4-difluoropyromellitic dianhydride represented by formula (12): ##STR1## and 1,4-difluoropyromellitic acid represented by formula (15): ##STR2## by dehydrating or hydrolyzing and dehydrating precursors.

Method for preparing aromatic compounds

A perfluorinated polyimide comprising a repeating unit represented by general formula (1): ##STR1## and a perfluorinated poly(amic acid) comprising a repeating unit represented by general formula (6): ##STR2## wherein R.sub.1 is a tetravalent organic group; and R.sub.2 is a divalent organic group, provided that chemical bonds between carbon atoms and monovalent elements contained in R.sub.1 and R.sub.2 are exclusively carbon-to-fluorine bonds; methods for preparing them; and optical material including the perfluorinated polyimide. 1,4-Bis(3,4-dicarboxytrifluorophenoxy)-tetrafluorobenzene dianhydride, 1,4-difluoropyromellitic anhydride, 1,4-bis(3,4-dicarboxytrifluorophenoxy)-tetrafluorobenzene, 1,4-difluoropyromellitic acid, and 1,4-bis(3,4-dicyanotrifluorophenoxy)-tetrafluorobenzene as well as methods preparing them. The perfluorinated polyimide has a thermal stability and has a low optical loss in an optical communication wavelength region (0.8 to 1.7 .mu.m).

A perfluorinated aromatic compound represented by general formula (7): ##STR1## wherein R.sub.3 is a tetravalent perfluorinated aromatic group represented by formula (8): ##STR2## wherein (R.sub.4)s are the same, each being a carboxyl group or a cyano group, or two adjacent (R.sub.4)s combine to form a divalent group represented by formula (10): ##STR3## provided that when R.sub.4 is a cyano group, R.sub.3 denotes said tetravalent perfluorinated aromatic group represented by formula (9).

Perfluorinated aromatic compounds

Optical waveplate and A method of manufacturing the optical waveplate

A polyimide optical waveguide comprising a core made of polyimide whose refractive index is controlled to a predetermined value by electron beam irradiation, and a cladding set in contact with the core and having a refractive index lower than that of the core.

Polyimide optical waveguide and method of manufacturing the same

Polimide optical waveguide

A polyimide optical material, composed of a perfluorinated polyimide having a perfluorinated repeating unit represented by general formula (1) ##STR1## wherein R.sub.1 is a tetravalent perfluorinated organic group; and R.sub.2 is a divalent perfluorinated organic group.

Polyimide optical material

A perfluorinated polyimide comprising a repeating unit represented by general formula (1): ##STR1## and a perfluorinated poly(amic acid) comprising a repeating unit represented by general formula (6): ##STR2## wherein R.sub.1 is a tetravalent organic group; and R.sub.2 is a divalent organic group, provided that chemical bonds between carbon atoms and monovalent elements contained in R.sub.1 and R.sub.2 are exclusively carbon-to-fluorine bonds; methods for preparing them; and optical material including the perfluorinated polyimide. 1,4-Bis(3,4-dicarboxytrifluorophenoxy)tetrafluorobenzene dianhydride, 1,4-difluoropyromellitic anhydride, 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrafluorobenzene, 1,4-difluoropyromellitic acid, and 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrafluorobenzene as well as methods preparing them. The perfluorinated polyimide has a thermal stability and has a low optical loss in an optical communication wavelength region (0.8 to 1.7 .mu.m).

Perfluorinated polyimide, perfluorinated poly(amic acid), starting

An optical waveguide which has properties including low optical losses, facile fabrication, controllable core-cladding refractive index ratio, and a high heat resistance is provided. The optical waveguide for light transmission therethrough has a core made of a polyimide obtained from at least one tetracarboxylic acid dianhydride and at least one diamine. The polyimide is (a) a polyimide homopolymer derived from a diamine represented by formula [I] as follows: ##STR1## (b) a polyimide copolymer derived from at least one diamine including the diamine represented by the formula [I]; or (c) a mixture of the polyimide homopolymers.

Polyimide optical waveguide

Growing community of inventors

Tokyo, Japan

Shinji Ando