Mitsubishi Gas Chemical Company, Inc.

Masanori Shimuta

Motoharu Takeuchi

Hiroshi Horikoshi

Kenichi Takahashi

Akikazu Amagai

Yuichi Yoshimura

Hiroyuki Okada

Osamu Aoki

Masaki Tamura

Nobuyuki Uemura

Katsuyuki Mizuno

Takahiro Matsui

Toru Takahashi

Hisato Abe

Akira Kurata

Masamichi Mizukami

Atsuki Niimi

Akihiko Konishi

Akikazu Amagi

Minoru Ohashi

In the present invention, an episulfide compound having, in one molecule, at least one epithio structure represented by the following Formula 2: wherein Ris C1-C10 hydrocarbylene or single bond, R, Rand Rare each independently C1-C10 hydrocarbyl or hydrogen, Y is O, S, Se or Te, p is an integer from 1 to 5 and q is an integer from 0 to 5,is polymerized in the presence of a halide of a 13-16 group element of the long periodic table and/or a polymerization regulator represented by the following Formula 1: wherein R, Rand Rare each C1-C10 hydrocarbyl or hydrogen, Ris C1-C10 hydrocarbylene or single bond, X is F, Cl, Br, I, As, SH, OH, C1-C10 alkoxyl, C1-C10 alkylthio, or C1-C10 mercaptoalkylthio, and m is an integer from 1 to 5, to produce a cured resin suitable as an optical material. By using the polymerization regulator, the polymerization rate of the episulfide compound can be suitably regulated to obtain a cured resin with less defect. By using the halide, the increase in the viscosity of the starting composition during the storage or the casting operation can be prevented.

Polymerization regulator and composition for resin

Episulfide compounds useful as starting materials of optical materials are stably stored for a long period of time at a temperature ranging from their solidifying points to 20&#xb0; C., preventing the production or precipitation of polymers and the yellowing.

Method of storing episulfide compound

In the present invention, an episulfide compound having, in one molecule, at least one epithio structure represented by the following Formula 2: wherein Ris C1&#x2013;C10 hydrocarbylene or single bond, R, Rand Rare each independently C1&#x2013;C10 hydrocarbyl or hydrogen, Y is O, S, Se or Te, p is an integer from 1 to 5 and q is an integer from 0 to 5,is polymerized in the presence of a halide of a 13&#x2013;16 group element of the long periodic table and/or a polymerization regulator represented by the following Formula 1: wherein R, Rand Rare each C1&#x2013;C10 hydocarbyl or hydrogen, Ris C1&#x2013;C10 hydrocarbylene or single bond, X is F, Cl, Br, I, As, SH, OH, C1&#x2013;C10 alkoxyl, C1&#x2013;C10 alkylthio, or C1&#x2013;C10 mercaptoalkythio, and m is an integer from 1 to 5,to produce a cured resin suitable as an optical material. By using the polymerization regulator, the polymerization rate of the episulfide compound can be suitably regulated to obtain a cured resin with less defect. By using the halide, the increase in the viscosity of the starting composition during the storage or the casting operation can be prevented.

Polymerization regulators and compositions for resin

A composition for a resin which comprises (a) a compound having one or more structures represented by the following formula in one molecule:

Compositions for a resin

A resinous composition which comprises a compound having, in one molecule, one or more structures of the formula (1) ##STR1## wherein R.sup.1 is a hydrocarbon having 1 to 10 carbon atoms; R.sup.2, R.sup.3 and R.sup.4 are each hydrogen or a hydrocarbon group having 1 to 10 carbon atoms; and X is S or O, and a ratio of S to the total of S and O constituting the three-membered ring is 50% or more on the average; and another compound having one or more SH groups in one molecule. The resinous composition can be used for an optical material having improved oxidation resistance.

Resin for optical material

An episulfide which has an alicyclic, aromatic or heterocyclic skeleton and has two or more moieties represented by the formula ##STR1## wherein X is S or O, and S is in an amount of 50% or more, on the average, of the total of S and O constituting a three-membered ring. A cured material obtained by polymerizing this episulfide compound is a desirable optical material for various uses, particularly as a lens material for spectacles.

Episulfide compound

The present invention provides a composition comprising a vinylbenzylthio compound represented by the following general formula ##STR1## in which m is an integer of 2-3, n is an integer of 1 and R is a hydrocarbon group of 3-6 carbon atoms or a hydrocarbon group of 3-6 carbon atoms containing a bivalent sulfur atom, and a monomer radical-copolymerizable with said vinylbenzylthio compound. Said composition is useful for producing a plastic lens having a high refractive index, a small specific gravity, excellent heat resistance and excellent processability.

Composition for high refractive index lens comprising copolymer of

The present invention provides a composition comprising, as the essential components, an aromatic compound represented by the following general formula ##STR1## (m is an integer of 2-3, n is an integer of 1-3 and R is a hydrocarbon group of 3-6 carbon atoms or a hydrocarbon group of 3-6 carbon atoms containing a bivalent sulfur atom), an isocyanate compound and a radical polymerization initiator. Said composition is useful for producing a plastic lens having a high refractive index, a small specific gravity, excellent heat resistance and excellent processability.

Composition for high refractive index lens comprising a copolymer of a

Contact lenses are treated with hydrogen peroxide and the remaining hydrogen peroxide is decomposed by electrolysis.

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Mie, Japan

Masanori Shimuta