Abstract: There is provided a polyorganosiloxane composition capable of providing a cured product which has low hardness, high transparency, high tensile strength, and low surface tackiness. A curable polyorganosiloxane composition includes: (A) alkenyl group-containing polyorganosiloxane containing straight-chained polyorganosiloxane composed of (A1) both ends alkenyl group polyorganosiloxane having a predetermined viscosity and (A2) polyorganosiloxane having a predetermined viscosity and having 0.6 or more and less than 2 alkenyl groups on average, and (A3) resinous polyorganosiloxane; (B) polyorganohydrogensiloxane composed of (B1) both ends Si—H-containing straight-chained polyorganosiloxane, and (B2) polyorganosiloxane having 3 or more Si—H; and (C) a hydrosilylation reaction catalyst, in mounts that satisfy predetermined relationships.

Abstract: To provide a polyorganosiloxane composition whose cured product has uniform good flame retardancy and good physical properties with less discoloring, for example, yellowing, and which has excellent temporal stability when stored. A flame-retardant polyorganosiloxane composition contains: (A) straight-chain polyalkylsiloxane having two or more alkenyl groups in one molecule and having a 10,000 to 1,000,000 mPa·s viscosity (25° C.); (B) resinoid polyorganosiloxane containing a Q unit and having 1.5 or more alkenyl groups on average, mass % of the component (B) being 30 to 80 mass % of the total of the components (A), (B); (C) polyorganohydrogensiloxane having three or more Si—H, an amount of the component (C) being such that Si—H/(total of the alkenyl groups in the components (A), (B)) becomes 1.0 to 3.0 moles; and (D) a catalytic amount of a hydrosilylation reaction catalyst, wherein the total content of phosphorus and an alkali metal is 20 mass ppm or less.

Abstract: To provide a polyorganosiloxane composition with good moldability, and a cured product with good mold release property and excellent non-contamination property to the metal mold. A polyorganosiloxane composition for molding includes: (A) a straight-chain polyorganosiloxane having two or more alkenyl groups in one molecule, and having a viscosity (at 25° C.) of 10,000 to 1,000,000 mPa·s; (B) 30 to 80 mass % of a resinoid polyorganosiloxane containing Q units, and having 1.5 or more alkenyl groups on average in one molecule, to a total of the components (A) and (B); (C) a polyorganohydrogensiloxane containing M units and Q units, having a molar ratio of alkoxy groups and Si—H of less than 0.15, and having a mass decrease rate when heated at 150° C. for 30 minutes of 2.0% or less, wherein an amount of the (Si—H/alkenyl groups) is 1.0 to 3.0 mol; and (D) a catalytic amount of a hydrosilylation reaction catalyst.

Abstract: To provide a method of manufacturing a silicone cured product and a silicone cured product which allow generation of a volatile component to be reduced significantly even being exposed to high temperatures of room temperature or more for a long time. A method of manufacturing a silicone cured product includes: curing an additional polyorganosiloxane composition by hydrosilylation reaction under closed atmosphere at a temperature of 40° C. or more and 200° C. or less to obtain a primary cured product; and heating the primary cured product under open atmosphere or reduced pressure at a temperature of 60° C. or more and 160° C. or less, and a silicone cured product in which when heated at 150° C. for 16 hours, a total generation amount of an alcohol having 1 to 3 carbon atoms and an oxide thereof, and an alkyl group-containing silane compound having 1 to 3 carbon atoms is 10 ppm or less.

Abstract: A polyorganosiloxane composition for molding includes: (A) a straight-chain polyorganosiloxane having two or more alkenyl groups and having a viscosity (25° C.) of 10,000 to 500,000 mPa·s; (B) 30 to 80 mass % of a resinoid polyorganosiloxane including M, D, and Q units, at a molar ratio of a:b:c, on average (0.3?a?0.6, 0?b?0.1, 0.4?c?0.7, and a+b+c=1), and having two or more alkenyl groups; (C) an amount of a polyorganohydrogensiloxane having Si-bonded hydrogen atoms, an average degree of polymerization of 10 or more, a content of the Si-bonded hydrogen atoms of 5.0 mmol/g or more and 11.0 mmol/g or less, and a mass decrease rate up to 140° C. by TGA of 2.0 mass % or less so that an amount of the (Si-bonded hydrogen atoms/alkenyl groups) is 1.0 to 3.0 mol; and (D) a hydrosilylation reaction catalyst. A cured product excellent in mold release property is obtained and contamination of a metal mold is prevented.

Abstract: This flame-retardant polyorganosiloxane includes (A) a straight-chain polyorganosiloxane having two or more alkenyl groups in one molecule and whose viscosity (25° C.) is 10,000 to 1,000,000 mPa·s; (B) 30 to 80 mass % of a resinoid polyorganosiloxane which includes Q unit and has 1.5 or more alkenyl groups on average, and in which a molar ratio of alkoxy groups to alkyl groups is 0.030 or less; (C) an amount of a polyorganohydrogensiloxane, whose average degree of polymerization is 10 or more, and in which a Si—H content is 5.0 mmol/g or more, in which Si—H/(a total of alkenyl groups) is 1.0 to 3.0 mol; and (D) a hydrosilylation reaction catalyst. A flame-retardant polyorganosiloxane composition capable of reducing an amount of a platinum-based metal compound is provided.

Abstract: A polyorganosiloxane composition for molding includes: (A) a straight-chain polyorganosiloxane having two or more alkenyl groups and having a viscosity (25° C.) of 10,000 to 500,000 mPa·s; (B) 30 to 80 mass % of a resinoid polyorganosiloxane including M, D, and Q units, at a molar ratio of a:b:c, on average (0.3?a?0.6, 0?b?0.1, 0.4?c?0.7, and a+b+c=1), and having two or more alkenyl groups; (C) an amount of a polyorganohydrogensiloxane having Si-bonded hydrogen atoms, an average degree of polymerization of 10 or more, a content of the Si-bonded hydrogen atoms of 5.0 mmol/g or more and 11.0 mmol/g or less, and a mass decrease rate up to 140° C. by TGA of 2.0 mass % or less so that an amount of the (Si-bonded hydrogen atoms/alkenyl groups) is 1.0 to 3.0 mol; and (D) a hydrosilylation reaction catalyst. A cured product excellent in mold release property is obtained and contamination of a metal mold is prevented.

Abstract: This flame-retardant polyorganosiloxane includes (A) a straight-chain polyorganosiloxane having two or more alkenyl groups in one molecule and whose viscosity (25° C.) is 10,000 to 1,000,000 mPa·s; (B) 30 to 80 mass % of a resinoid polyorganosiloxane which includes Q unit and has 1.5 or more alkenyl groups on average, and in which a molar ratio of alkoxy groups to alkyl groups is 0.030 or less; (C) an amount of a polyorganohydrogensiloxane, whose average degree of polymerization is 10 or more, and in which a Si—H content is 5.0 mmol/g or more, in which Si—H/(a total of alkenyl groups) is 1.0 to 3.0 mol; and (D) a hydrosilylation reaction catalyst. A flame-retardant polyorganosiloxane composition capable of reducing an amount of a platinum-based metal compound is provided.

Abstract: The silicone composition for sealing a semiconductor, comprises: (A) 100 parts of a polyorganosiloxane having one or more alkenyl groups, obtained by reacting (a1) 60 to 99 parts of an organosiloxane containing at least a trifunctional siloxane unit not taking part in a hydrosilylation reaction, with (a2) 40 to 1 parts of an organosiloxane containing a bifunctional siloxane unit having an alkenyl group and/or a monofunctional siloxane unit having an alkenyl group; (B) an amount of a polyorganohydrogensiloxane having two or more hydrogen atoms having a viscosity at 25° C. of 1 to 1000 mPa·s so that an amount of the hydrogen atoms is 0.5 to 3.0 mol per mol of the alkenyl groups; and (C) a platinum-based catalysts, wherein a decrease in storage modulus of a cured product thereof from 25° C. to 50° C. is 40% or more.

Abstract: The silicone composition for sealing a semiconductor, comprises: (A) 100 parts of a polyorganosiloxane having one or more alkenyl groups, obtained by reacting (a1) 60 to 99 parts of an organosiloxane containing at least a trifunctional siloxane unit not taking part in a hydrosilylation reaction, with (a2) 40 to 1 parts of an organosiloxane containing a bifunctional siloxane unit having an alkenyl group and/or a monofunctional siloxane unit having an alkenyl group; (B) an amount of a polyorganohydrogensiloxane having two or more hydrogen atoms having a viscosity at 25° C. of 1 to 1000 mPa·s so that an amount of the hydrogen atoms is 0.5 to 3.0 mol per mol of the alkenyl groups; and (C) a platinum-based catalysts, wherein a decrease in storage modulus of a cured product thereof from 25° C. to 50° C. is 40% or more.

Abstract: The silicone composition for sealing a semiconductor, comprises: (A) 100 parts of a polyorganosiloxane having one or more alkenyl groups, obtained by reacting (a1) 60 to 99 parts of an organosiloxane containing at least a trifunctional siloxane unit not taking part in a hydrosilylation reaction, with (a2) 40 to 1 parts of an organosiloxane containing a bifunctional siloxane unit having an alkenyl group and/or a monofunctional siloxane unit having an alkenyl group; (B) an amount of a polyorganohydrogensiloxane having two or more hydrogen atoms having a viscosity at 25° C. of 1 to 1000 mPa·s so that an amount of the hydrogen atoms is 0.5 to 3.0 mol per mol of the alkenyl groups; and (C) a platinum-based catalyst, wherein a decrease in storage modulus of a cured product thereof from 25° C. to 50° C. is 40% or more.

Abstract: One embodiment is related to a silicone composition for sealing a light emitting element, the composition comprising: (A) a vinyl group-containing organopolysiloxane having a three-dimensional network structure; (B) an organohydrogenpolysiloxane which has at least two hydrogen atoms, each hydrogen atom being bonded to a silicon atom per molecule; and (C) a hydrosilylation catalyst.

Abstract: One embodiment is related to a silicone composition for sealing a light emitting element, the composition comprising: (A) a vinyl group-containing organopolysiloxane having a three-dimensional network structure; (B) an organohydrogenpolysiloxane which has at least two hydrogen atoms, each hydrogen atom being bonded to a silicon atom per molecule; and (C) a hydrosilylation catalyst.

Abstract: A silicone composition for sealing a light emitting element includes: (A) a vinyl group-containing organopolysiloxane having a three-dimensional network structure represented by an average unit formula: (SiO4/2)a(ViR2SiO1/2)b(R3SiO1/2)c (where Vi represents a vinyl group, R's are identical or different substituted or unsubstituted monovalent hydrocarbon groups other than alkenyl groups, and a, b, and c are positive numbers satisfying that a/(a+b+c) is 0.2 to 0.6 and b/(a+b+c) is 0.001 to 0.2); (B) an organohydrogenpolysiloxane which has at least two hydrogen atoms, each hydrogen atom being bonded to a silicon atom per molecule, the organohydrogenpolysiloxane being contained in such an amount that an amount of a hydrogen atom bonded to a silicon atom is 0.3 to 3.0 mol per 1 mol of a vinyl group bonded to a silicon atom in the component (A); and (C) a hydrosilylation catalyst (catalytic amount), wherein a coefficient of linear expansion of the composition after curing is 10×10?6 to 290×10?6/° C.

Abstract: A silicone composition for sealing a light emitting element includes: (A) a vinyl group-containing organopolysiloxane having a three-dimensional network structure represented by an average unit formula: (SiO4/2)a(ViR2SiO1/2)b(R3SiO1/2)c (where Vi represents a vinyl group, R's are identical or different substituted or unsubstituted monovalent hydrocarbon groups other than alkenyl groups, and a, b, and c are positive numbers satisfying that a/(a+b+c) is 0.2 to 0.6 and b/(a+b+c) is 0.001 to 0.2); (B) an organohydrogenpolysiloxane which has at least two hydrogen atoms, each hydrogen atom being bonded to a silicon atom per molecule, the organohydrogenpolysiloxane being contained in such an amount that an amount of a hydrogen atom bonded to a silicon atom is 0.3 to 3.0 mol per 1 mol of a vinyl group bonded to a silicon atom in the component (A); and (C) a hydrosilylation catalyst (catalytic amount), wherein a coefficient of linear expansion of the composition after curing is 10×10?6 to 290×10?6/° C.

Abstract: A brake system in a buggy includes first and second brake shafts which are disposed on one side of the left and right differential output shafts in a longitudinal direction of the vehicle and in parallel to the left and right differential output shafts and which are driven at increased speeds by the left and right differential output shafts. The first and second brake shafts and the first and second brakes are accommodated within a reduction case, so that the first and second brakes are cooled by lubricating oil within the reduction case. Thus, the brake system in the buggy can be mounted at a high level above the ground; is excellent in dustproof and waterproof properties; is cooled satisfactorily, and moreover, is capable of reliably braking left and right wheels simultaneously.

Abstract: A brake for a buggy vehicle includes a plurality of rotatable friction brake plates which are axially slidably and relatively non-rotatably coupled to the input shaft of a reduction device spline-coupled to a propelling shaft, a plurality of stationary friction brake plates alternately superposed with the rotatable friction brake plates, a brake non-rotatable housing which houses the group of the rotatable and stationary friction brake plates therein and which supports said stationary friction brake plates for axially sliding movement and against rotation, a pressure-receiving portion provided in the brake housing to carry one side of the group of the rotatable and stationary friction brake plates, and an operating device capable of urging the other side of the group of the rotatable and stationary friction brake plates against the pressure receiving portion.

Abstract: A wet multi-plate clutch includes a clutch outer connected to an input member, a clutch inner relatively rotatably disposed within the clutch outer and connected to an output member, a plurality of first friction plates axially slidably spline-fitted to an inner peripheral wall of the clutch outer and accommodated within the clutch outer, a plurality of second friction plates axially slidably spline-fitted to an outer peripheral wall of the clutch inner and superposed one on another alternately with the first friction plates, and a clamping device capable of clamping groups of the first and second friction plates axially to bring adjacent ones of the first and second friction plates into friction engagement with each other. In this wet multi-plate clutch, stopper devices are mounted at opposite ends of a spline groove in the clutch outer for limiting the distance of sliding movement of spline teeth of the group of the first friction plates.