Dow Corning Toray Silicone Company Limited

Toray Silicone Company Limited

Dow Corning Corporation

Atsushi Togashi

Toshio Saruyama

Takateru Yamada

Junji Nakanishi

Nobuo Kaiya

Taku Koyama

Michael Ward Skinner

Toyohiko Yamadera

Akira Kasuya

Teruyuki Nakagawa

John Darrell Jones

This invention relates to a silicone composition comprising: (A) a mixture of (i) a linear trimethylsiloxy-terminated polydiorganosiloxane containing at least 2 alkenyl groups having at least 4 carbon atoms and (ii) optionally a linear dimethylalkenylsiloxy-terminated polydiorganosiloxane, (B) a polyorganohydrogensiloxane, (C) a catalytic quantity of a platinum catalyst, and (D) an inhibitor. The silicone compositions of this invention make it possible to form cured release films with low resistance to peeling when peeling is carried out at high speeds, and with the possibility of controlling the resistance to peeling between low and high values when peeling is carried out at low speeds. The silicone compositions of this invention also are not subject to a decrease in the coefficient of residual adhesion in the adhesive material applied onto a cured release film.

Silicone composition for forming cured release films

This invention relates to a silicone release coating composition comprising an organopolysiloxane having at least 2 alkenyl groups in each molecule, an organopolysiloxane having at least 3 silicon-bonded hydrogen atoms in each molecule, a carbon-carbon triple bond-functional alcohol having a boiling point at ambient pressure of at least 140.degree. C., an organosilicon compound having at least 3 carbon-carbon triple bond-functional hydrocarbon groups bonded across oxygen to silicon, and a platinum catalyst. The silicone release coating compositions of this invention have excellent bath stability, form a very stable thin film on applicator rolls, cure rapidly even at relatively low temperatures, have stable curing characteristics during the course of bath aging, and exhibit stable release values during the course of bath aging.

Silicone release coating compositions

The thermosetting silicone composition of the instant invention is comprised of (a) a diorganopolysiloxane containing alkenyl groups, (b) an organohydrogenpolysiloxane, (c) a platinum catalyst-containing silicone resin fine particle catalyst comprised of (i) a thermoplastic silicone resin containing 5 to 90 mole % PhSiO.sub.3/2 siloxane units and 5 to 20 mole % MeViSiO.sub.2/2 siloxane units, wherein Ph denotes phenyl, Me denotes methyl and Vi denotes vinyl; said resin having a glass transition point of 40.degree. to 70.degree. C. and (ii) 0.05 to 2 wt % as platinum atoms of a platinum catalyst; and (d) a hydrosilation reaction inhibiting compound. The thermosetting silicone compositions have excellent storage stability at about room temperature, and cure at a fast rate when heated.

Thermosetting silicone composition

A microparticle catalyst for hydrosilylation reactions which contains microparticles of an average particle diameter of 0.1 to 20 .mu.m made of a metallic catalyst for hydrosilylation reactions; a disiloxane having the general formula (R.sup.1 R.sup.2 ArSi).sub.2 O, wherein, R.sup.1 is an alkenyl group, R.sup.2 is a monovalent hydrocarbon group and Ar is an aryl group; and a resin having a glass transition temperature of 40.degree. to 200.degree. C. and thermosetting silicone composition containing the microparticle catalyst.

Microparticle catalysts for hydrosilylation reactions and thermosetting

The present invention relates to a curable silicone release coating composition comprising a mixture of an organopolysiloxane containing at least two alkenyl groups per compound, an organohydrogensilicon compound, inhibitors having a boiling point of up to 130.degree. C. at atmospheric pressure, inhibitors having a boiling point of at least 170.degree. C. at atmospheric pressure a platinum group metal-containing catalyst, and optionally a diluent. The silicone release coating compositions are stable when stored at room temperature, especially when the composition is used on a coating roll for the production of a thin films. The compositions of this invention also quickly form a cured film having good release properties for adhesive materials at a comparatively low temperatures.

Silicone release coating compostions

The present invention relates to a process for forming a laminate and the laminate using silicone release coating compositions comprising (A) a mixture of (i) a dimethylsiloxane-methylvinylsiloxane-methylphenylsiloxane copolymer and (ii) a dimethylsiloxane-methylvinylsiloxane copolymer, (B) an organohydrogenpolysiloxane, (C) a platinum catalyst, and (D) an organic solvent. The silicone release coating compositions of the present invention provide small release resistance values both at low and high peeling velocities and do not impair the residual adhesion of tacky substances that have come into contact with the coating.

Process for forming a laminate

The present invention relates to silicone release coating compositions comprising (A) a mixture of (i) a dimethylsiloxane-methylvinylsiloxane-methylphenylsiloxane copolymer and (ii) a dimethylsiloxanemethylvinylsiloxane copolymer, (B) an organohydrogenpolysiloxane, (C) a platinum catalyst, and (D) an organic solvent. The silicone release coating compositions of the present invention provide small release resistance values both at low and high peeling velocities and do not impair the residual adhesion of tacky substances that have come into contact with the coating.

Silicone compositions for the formation of cured release coatings

Silicone resins containing monorganosiloxane and diorganosiloxane units and exhibiting reproducible values of molecular weight and dispersity are prepared by condensing a mixture of hydrolyzed silanes, adjusting the solids content of the condensed resin and then subjecting the resultant product to a re-equilibration reaction in the presence of an alkali metal compound.

Method for preparing silicone resins

This invention provides a novel class of organohydrogenpolysiloxanes that function as curing agents for organosiloxane compositions curable by a hydrosilylation reaction in addition to imparting excellent adhesion to the cured composition. This invention also provides curable organosiloxane compositions containing these novel organohydrogen-polysiloxanes. The compositions exhibit excellent adhesion to a variety of organic and inorganic substrates, including but not limited to metals, glasses, and plastics.

Organohydrogenpolysiloxanes and curable organosiloxane compositions

Microparticles of a hydrosilylation catalyst encapsulated in a thermoplastic resin are prepared by forming a solution containing the hydrosilylation catalyst and a thermoplastic resin with a glass-transition temperature or softening point of 40.degree. to 200.degree. C. dissolved in a solvent, and then spraying this solution as droplets into a hot gas current in order to volatilize the solvent while solidifying said thermoplastic resin during entrainment of the droplets in the gas current.

Method for preparing microparticles of a thermoplastic resin containing

The combination of a microencapsulated hydrosilylation catalyst selected from the group consisting of metals from the platinum group of the periodic table and compounds of these metals and a known inhibitor for this type of catalyst impart excellent storage stability to organosiloxane compositions that cure by a hydrosilation reaction while enabling these compositions to rapidly cure at temperatures above the softening temperature of the thermoplastic resin used to encapsulate the hydrosilylation catalyst. The curing rate of the composition is faster relative to compositions containing the microencapsulated catalyst without the catalyst inhibitor.

Thermosetting organosiloxane composition

This invention provides particulate catalyst compositions comprising a platinum-containing hydrosilation reaction catalyst and a polydiorganosilane exhibiting a softening point of from 50.degree. to 200.degree. C. The average particle size of the particulate does not exceed 100 micrometers, and the surface layer of the particulate is substantially free of said catalyst. Curable organopolysiloxane compositions containing the present catalyst compositions exhibit excellent storage stability.

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Chiba Prefecture, Japan

Atsushi Togashi