Shin-etsu Chemical Co., Ltd.

Menicon Co., Ltd.

Toshio Yamazaki

Shoji Ichinohe

Ichiro Ando

Eri Ito

Yasuhiro Yokoyama

Masaaki Yamaya

Hideyoshi Yanagisawa

Kazuhiko Nakada

Tsuyoshi Watanabe

Masayuki Takahashi

Sadayasu Tanikawa

Noriko Iwata

Hiroshi Yoshioka

Toru Kawaguchi

Haruyuki Hiratani

Nobuyuki Toyoshima

Hideto Kato

Noriyuki Meguriya

Yasushi Yamamoto

Toshiyuki Ozai

Atsushi Yaginuma

Masayuki Yoshida

Shinichi Morioka

Yuriko Watanabe

Noriko Yoshimatsu

Akira Yamamoto

Toshinobu Ishihara

Tsutomu Nakamura

Tohru Kubota

Takeo Yoshida

Akinari Itagaki

Nobu Kato

Hideki Sugahara

Kazuhiro Oishi

Mouad Lamrani

Takanori Shibata

Shinichi Ide

Satoshi Uchida

Atsushi Hirashima

Nobuyuki Suzuki

Shigeo Mochizuki

Akinori Okumura

Masahiro Matsumoto

Kazuhiko Nakata

Nobuyuki Syzuki

Ichinobe Shoji

Shouji Ichinohe

An addition curing silicone rubber composition and a cured product thereof are provided. In this composition, amount of the low molecular weight siloxane component volatilizing from the cured product has been reduced, and as a consequence, this composition is free from the problems such as clouding or haze, contact fault, adhesion failure, and hydrophobicization of the surface caused by the deposition of the volatilized low-molecular weight siloxane component on the surrounding surfaces. More specifically, the addition curing silicone rubber composition comprises; (A) 100 parts by weight of a polyorganosiloxane containing, on average, at least two alkenyl groups which are bonded to silicon atom; (B) 0.3 to 20 parts by weight of an organohydrogenpolysiloxane containing at least two hydrogen atoms which are bonded to silicon atom (SiH functional groups) per molecule; and (C) a catalytic amount of a addition reaction catalyst, and content of the polyorganosiloxane having a degree of polymerization of up to 10 and containing at least one SiH functional group per molecule is up to 0.5% by weight in relation to the entire composition.

Addition curing silicone rubber composition and its cured product

An addition curable self-adhesive silicone rubber composition comprising (A) an organopolysiloxane containing at least two alkenyl groups, (B) an organohydrogenpolysiloxane containing at least three SiH groups, (C) an aromatic ring-free organohydrogenpolysiloxane containing at least two SiH groups, and (F) an addition reaction catalyst, with a SiH/alkenyl molar ratio ranging from 0.8 to 5.0, is briefly moldable and cures to various metals and organic resins.

Addition curable self-adhesive silicone rubber composition

A triorganosiloxy end-capped organopolysiloxane, i.e., organopolysiloxane having a backbone consisting essentially of repeating (3,3,3-trifluoropropyl)methylsiloxane units and end-capped with triorganosiloxy groups is prepared by copolymerizing tris(3,3,3-trifluoropropyl)trimethylcyclo-trisiloxane with a silanol end-capped organopolysiloxane in the presence of an alkyllithium or lithium silanolate catalyst to form a silanol end-capped copolymer, and adding a trialkylsilyl triflate or strong acid in excess relative to the catalyst and a hexaorganodisilazane for effecting end-capping and neutralization.

Preparation of triorganosiloxy end-capped organopolysiloxane

A silicone rubber coating composition comprising (A) a diorganopolysiloxane containing an average of at least two alkenyl groups, (B) silica powder having a specific surface area of at least 50 m/g, (C) an organosilicon compound containing a ureido group, an isocyanuric acid ester modified with an organosilicon compound or a (partial) hydrolytic condensate thereof, and (D) a curing agent is applied and vulcanized to base fabric to form a coated fabric, from which airbags are prepared. The composition has a sufficient adhesion to withstand high temperature and abrupt elongation upon inflation of the airbag even after long-term storage under hot humid conditions.

Silicone rubber coating composition and airbag

Process for preparing ocular lens with urethane compound and process for preparing urethane compound for medical instruments

A process for preparing an urethane compound for medical instruments, characterized by reacting a hydroxyl compound (A) with an isocyanate compound (B) in the absence of a catalyst or in the presence of a reaction catalyst other than an organic tin compound to give an urethane compound (I). According to the process, the urethane compound showing high safety can be easily prepared, in particular, while molecular weight of the compound is controlled.

Process for preparing urethane compound for medical instruments

A coating composition comprising (A) a urethane polymer having at least one aliphatic unsaturated hydrocarbon group on a side chain in a molecule, (B) an organohydrogenpolysiloxane having at least two hydrosilyl groups in a molecule, and (C) a hydrosilylation catalyst firmly bonds to surfaces of various substrates, especially silicone rubber substrates, without a need for pre-treatment and readily forms thereon a surface protective layer having wear resistance. A silicone rubber member in which a silicone rubber substrate is coated on its surface with the inventive coating composition is endowed on the surface with wear resistance and is useful as silicone rubber key pads and silicone rubber rolls.

Coating composition and coated silicone rubber member

A substantially non-crosslinked water-absorptive soft ocular lens material obtained by polymerizing polymerizable components comprising a methoxysilane compound (A) of the formula (I):

Water-absorptive soft ocular lens material, water-absorptive soft ocular

A water-absorptive soft contact lens material having a high transparency, an excellent flexibility, a high oxygen permeability independent of water content, a high mechanical strength and an adequate hardness, which comprises a copolymer prepared by the polymerization of a monomer mixture comprising an N,N-dialkyl acrylamide or methacrylamide, an N-vinyllactam and a bis(silicon-containing alkyl) fumarate in a specific ratio, and which provides water-absorptive soft contact lenses having excellent properties such as high transparency and high oxygen permeability.

Water-absorptive soft contact lens material and contact lens made thereof

An ocular lens obtained by reacting a hydroxyl group-containing polymer shaped to have an ocular lens shape, with a silicon-containing compound of the formula (I):

Ocular lens and a method for its production

Resins having a group reactive with an isocyanate group on a side chain are modified with isocyanatosiloxanes. In one form, the isocyanatosiloxane is a single end isocyanatosiloxane obtained by effecting addition reaction between a single end hydrogenosiloxane and an isocyanate group-containing organic silicon compound having one isocyanate group and at least one aliphatic unsaturated hydrocarbon group. A single end isocyanatosiloxane obtained by introducing an isocyanate group into a single end primary aminosiloxane is also useful. In another form, the isocyanatosiloxane is a polyfunctional isocyanatosiloxane which is obtained by effecting addition reaction between a hydrogenosiloxane having at least two SiH groups and an isocyanate group-containing organic silicon compound having one isocyanate group and one aliphatic unsaturated hydrocarbon group.

Modification of resins with isocyanatosiloxanes

A transparent ocular lens material comprising a silicon-containing polymer having a recurring unit represented by the general formula (I): ##STR1## wherein each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 is independently hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms or a group represented by the general formula (lI): ##STR2## in which each of R.sup.5, R.sup.6 and R.sup.7 is independently an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms or phenyl group. The ocular lens material has excellent transparency, high oxygen permeability and heat resistance, and excellent ultraviolet-ray absorbing properties and forming and processing properties, and has a relatively high refractive index.

Ocular lens material

A substantially non-crosslinked low water-absorptive ocular lens material obtained by polymerizing polymerizable components comprising a methoxysilane compound (A) of the formula (I):

Low water-absorptive ocular lens material, low water-absorptive ocular

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Gunma-ken, Japan

Toshio Yamazaki