Mitsui Toatsu Chemicals, Incorporated

Mitsui Chemicals, Inc.

Ahiko Finetec, Ltd.

Shinichi Umeda

Teruyuki Nagata

Hideki Mizuta

Hiroshi Naruse

Yoshinobu Kanemura

Yoshihiro Irizato

Koju Okazaki

Mamoru Tanaka

Chitoshi Shimakawa

Daisuke Tanaka

Soichiro Ahiko

The present invention provides an optical member including an organic polymer. This optical member includes a surface A which has an area of 1 mmor more, and in which the flatness of a region having an area of 1 mm, as measured by a non-contact type optical flatness meter, is 80 μm or less.

Optical member, method of producing optical member, and apparatus for transmitting optical information

A composition for polysulfide-based resin comprising a polythiol having 4 or more functional groups and a compound having a reactive unsaturated bond(s) and/or b epoxy group(s) and/or c iso(thio)cyanato group(s) in one molecule (however, a+b+c.gtoreq.2, and a and b are not simultaneously 0). A polysulfide-based resin obtained by curing the composition, an optical material comprising the resin, a lens consisting of the optical material and a method for producing the polysulfide-based resin are also set forth.

Polysulfide-based resin composition, polysulfide-based resin, and

The present invention discloses a sulfur-containing urethane-based resin composition of the present invention is directed to a sulfur-containing urethane-based resin composition which comprises a polythiol compound represented by formula (1): ##STR1## wherein X.sub.1, X.sub.2 and X.sub.3 each is a hydrogen atom or a mercapto group; x, y and z each is an integer of 0 to 8; and in their combinations, formula (1) has at least two mercapto groups, a polyiso(thio)cyanate compound, and a compound having two or more reactive unsaturated groups in an amount of 30 to 70% by weight based on the total weight of the composition, or a sulfur-containing urethane-based resin composition which comprises the polythiol compound represented by formula (1), the polyiso(thio)cyanate compound, the compound having two or more reactive unsaturated groups in an amount of 10 to 70% by weight based on the total weight, and a photopolymerization catalyst.

Sulfur-containing urethane-based resin composition, its resin, and

A novel bis-urea compound, preparation process of the compound, and preparation process of 1,3-dialkyl-2-imidazolidinone are disclosed and the disclosure provides a novel preparation process of 1,3-dialkyl-2-imidazolidinone and simultaneously enables effective utilization of N,N',N'-trialkyldiethylentriamine which lacks a large amount use and is desired to develop new application.

Process for producing 1,3-dialkyl-2-imidazolidinone

The present invention relates to 1,3,6-Trialkylhexahydro-1,3,6-triazocine-2-on represented by the formula (1): ##STR1## wherein R is a C.sub.1 .about.C.sub.8 alkyl group and a preparation process of the compound comprising reacting N,N',N'-trialkyldiethylenetriamine represented by the formula (2): ##STR2## wherein R is a C.sub.1 .about.C.sub.8 alkyl group, with urea, phosgene or carbon dioxide.

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Fukuoka-ken, Japan

Shinichi Umeda