Abstract: Provided is a curable organopolysiloxane composition that has strong initial pressure-sensitive adhesive strength in a process such as temporary fixing or the like, and that is easily peelable from a substrate in a subsequent process. Also provided is a method for using the composition. A curable organopolysiloxane composition including: (A) an organosiloxane component containing a silicon atom-bonded functional group (RA) containing a specific (meth)acrylic group, a resinous organosiloxane structure factor containing an alkenyl group, and a chain organopolysiloxane structure factor, (B) a siloxane component not containing a carbon-carbon multiple bond in each molecule, and (C) a photo-radical polymerization initiator; and use thereof.

Abstract: Provided is a curable organopolysiloxane composition that can be heat curable and photocurable, and that has sufficient tackiness, enabling design of a composition that can coat even when using a small amount of solvent, a cured product thereof, and use thereof. The curable organopolysiloxane composition comprises (A) a chain organopolysiloxane having an alkenyl group, (B) a specific MQ type organopolysiloxane resin, and (C) a radical polymerization initiator. As an optional component, the composition may further comprise (D) at least one type of radical reactive component selected from (D1) vinyl monomers, and (D2) (meth)acrylic group-containing organopolysiloxane compounds. The sum of component (A), component (B), and component (D2) with respect to the total solid mass of the composition is 50 mass % or higher.

Abstract: Provided is a curable organopolysiloxane composition that can be heat curable and photocurable, has excellent transparency, and forms a slightly adhesive layer, enabling design of a composition that is coatable even when using a small amount of solvent, a cured product thereof, and use thereof. The curable organopolysiloxane composition comprises (A) a chain organopolysiloxane having an alkenyl group, (B) at least one type of radical reactive component selected from (B1) vinyl monomers, and (B2) (meth)acrylic group-containing organopolysiloxane compounds, and (C) a radical polymerization initiator. The sum of component (A) and component (B2) with respect to the total solid mass of the composition is 50 mass % or higher.

Abstract: Provided is a hot-melt silicone composition that can be cured at various temperatures, that enables the design of the pressure-sensitive adhesive strength of a resulting cured product to a base material over a wide range, that has excellent transparency and yellowing resistance, and that has excellent handling workability. The composition comprises (A) 1 to 50 parts by mass of a chain organopolysiloxane having two or more alkenyl groups in a molecule, (B) 50 to 99 parts by mass of an MQ organopolysiloxane resin in which the molar ratio of M units to 1 mol of Q units is in the range of 0.5 to 2.0, and (C) 0.1 to 10 parts by mass of a radical polymerization initiator. Optionally, the composition comprises (D) another radical reactive component. The amount of component (B) is 50 mass % or more with respect to the total mass of the solid fraction of the composition.

Abstract: Provided is a silicone adhesive composition and an application thereof, that has a viscosity that enables coating even with a small amount of solvent content, has excellent curability due to hydrosilylation reaction, cures, has sufficient adhesive strength for practical use, and has excellent mechanical strength and elongation of the adhesive layer after curing, and can form a pressure-sensitive adhesive layer having sufficient adhesive strength for practical use.

Abstract: Provided is a hot-melt type silicone composition that can be cured at a wide range of temperatures from low to high depending on the sealing process and the heat resistance of the resin members, in particular, that can realize good curability even at low temperatures such as room temperature, that imparts excellent transparency and resistance to yellowing to the resulting cured product, and that has excellent workability and handling in, e.g., overmolding. The curable hot-melt silicone composition comprises: (A) a resin-linear structure-containing organopolysiloxane block copolymer having a resinous organosiloxane block X containing a triorganosiloxane unit (MRA unit) having silicon atom-bound functional group (RA) containing an acrylic group or a methacrylic group, and a Q unit, and a chain organosiloxane block Y, and having at least two of the RA groups in the molecule; and (B) a radical polymerization initiator. Also provided are uses of the hot-melt type silicone composition.

Abstract: A UV-curable silicone composition having storage stability and sufficient rapid curability is provided. A resulting cured product of the UV-curable silicone composition has high extensibility, maintains a strong adhesive strength under high temperature and high humidity conditions, and in which discoloration (yellowing) is suppressed, as a curable silicone composition used in an optical display or the like. Also provided is an application of a cured product thereof (OCR or the like). The UV-curable silicone composition comprises (A) a chain-like organopolysiloxane having a specific methacryloyl group-containing organic group, (B) a monofunctional or polyfunctional acrylate compound, and (C) a photopolymerization initiator. The ratio [(a)/(b)] of (a) the number of mols of methacroyl groups and (b) the number of mols of acryloyl groups in the composition is in a range of 0.1 to 3.0.

Abstract: Provided is a UV curable organopolysiloxane composition containing silicon atoms. A product obtained by curing the composition has low light transmittance in a predetermined UV wavelength range, and excellent workability when applied to a substrate. The UV curable composition of the present disclosure comprises: (S) 90 to 99.99 parts by mass of one or more of the following component (S1) or component (S2); (S1) an organopolysiloxane and/or organosilane having a UV curable functional group, (S2) a mixture containing (A) a compound with a UV curable functional group, with or without silicon atoms, and (B) an organopolysiloxane without a UV curable functional group, at a mass ratio of 5:95 to 95:5; and (C) 0.01 to 10 parts by mass of a UV absorbing compound. The total of component (S) and component (C) is 100 parts by mass.

Abstract: Provided is an organopolysiloxane compound serving as a raw material of an organopolysiloxane pressure-sensitive adhesive which has necessary and sufficient pressure-sensitive adhesive strength in a step such as temporary fixing or the like and can be easily peeled off from a substrate in a subsequent step; an organopolysiloxane pressure-sensitive adhesive composition containing the same; and a method for using the same. A chain co-modified organopolysiloxane containing a silicon-bonded functional group (RA) that contains a specific (meth)acrylic group and at least one aliphatic unsaturated carbon-carbon bond (RVi) (but excluding the functional group serving as RA above); a curable organopolysiloxane composition containing the same, further containing a crosslinking agent, a hydrosilylation reaction catalyst, and a photo-radical polymerization initiator, and having both heat curability and photo-curability.

Abstract: Provided is an organopolysiloxane compound serving as a raw material of an organopolysiloxane pressure-sensitive adhesive which has necessary and sufficient pressure-sensitive adhesive strength in a step such as temporary fixing or the like and can be easily peeled off from a substrate in a subsequent step; an organopolysiloxane pressure-sensitive adhesive composition containing the same; and a method for using the same. A chain co-modified organopolysiloxane containing a specific functional group having a (meth)acryl group (RA) and a functional group having an alcoholic hydroxyl group (ROH), wherein the amount of RA is in the range of 0.10 to 10.0 mol % with regard to all silicon atom-bonded functional groups in the molecule, and the average amount of ROH is in a range of 0.1 to 1.0 moles per mole of RA.

Abstract: Provided is a composition with a viscosity in which coating is possible even with a small amount of solvent, has excellent curability, and in which an Si-based pressure-sensitive adhesive (PSA) (e.g., PSA layer) formed by a curing reaction has a low (e.g., 50° C. or lower) glass transition temperature (Tg) despite having high PSA strength and tack, has favorable wettability, and has favorable mechanical strength and elongation; and an application of the same.

Abstract: This disclosure relates to a curable silicone composition that contains little to no solvent, has excellent transparency and adhesion to a substrate, and has a low overall haze value, and also relates to a cured product thereof. The curable silicone composition comprises: 100 mass parts of (A) a chain organopolysiloxane having an aliphatic unsaturated carbon-carbon bond-containing group and a degree of siloxane polymerization (DP) within a range of 10 to 1000; 1 to 100 mass parts of (B) a chain organopolysiloxane having an aliphatic unsaturated carbon-carbon bond-containing group and having a DP within a range of 1001 to 10,000; 0 to 100 mass parts of (C) an organopolysiloxane resin; (D) a polyorganohydrogen siloxane; and (E) a catalytic amount of a hydrosilylation reaction catalyst. Optionally, the composition further comprises: 0 to 60 mass parts of (F) an organic solvent, for 100 mass parts of the sum of components (A) to (D).

Abstract: Provided is a silicone adhesive composition and an application thereof, that has a viscosity that enables coating even with a small amount of solvent content, has excellent curability due to hydrosilylation reaction, cures, has sufficient adhesive strength for practical use, and has excellent mechanical strength and elongation of the adhesive layer after curing, and can form a pressure-sensitive adhesive layer having sufficient adhesive strength for practical use.

Abstract: A curable silicone composition is disclosed. The curable silicone composition comprises: (A) a linear organopolysiloxane having at least two silicon atom-bonded alkenyl groups per molecule, wherein at least 5 mole % of all silicon atom-bonded organic groups are aryl groups; (B) an organopolysiloxane containing siloxane units represented by the general formula R13SiO1/2 where each R1 represents an independently selected monovalent hydrocarbon group, and siloxane units represented by the general formula SiO4/2, wherein the amount of alkenyl groups is at least 6% by weight; (C) an organopolysiloxane having at least two silicon atom-bonded hydrogen atoms per molecule; and (D) a hydrosilylation reaction catalyst. The curable silicone composition forms a cured product with little weight reduction, little change in hardness, and little crack generation after thermal aging.

Abstract: A photocurable liquid silicone composition is disclosed. The photocurable liquid silicone composition comprises: (A) a straight chain organopolysiloxane having at least two alkenyl groups with 2 to 12 carbon atoms in a molecule, and not containing a mercaptoalkyl group; (B) an organopolysiloxane having at least two mercaptoalkyl groups in a molecule; (C) a branched chain organopolysiloxane, wherein alkenyl groups and mercaptoalkyl groups are not included; (D) a photo radical initiator containing a phosphorus atom; and (E) a hindered phenol compound. The photocurable liquid silicone composition is rapidly cured by irradiating with long wavelength light while providing excellent storage stability and coatability at room temperature and at low temperatures (e.g. approximately 0° C.), and provides a cured product that maintains transparency even when left under high temperature and high humidity conditions, with minimal clouding or discoloration.

Abstract: Provided is a resin-linear organopolysiloxane block copolymer which has a high degree of freedom in formulation due to excellent compatibility with other materials, in addition to exhibiting excellent film forming properties and followability of a film, while the stickiness of a film is suppressed. The resin-linear organopolysiloxane block copolymer has: a resin structure (A1) block that has siloxane units represented by R1SiO3/2 (wherein R1 represents a monovalent organic group, a hydroxyl group, or an alkoxy group having 1 to 6 carbon atoms) and SiO4/2; and a linear structure (A2) block represented by (R2SiO2/2)n (wherein n represents a number of 5 or more while R represents an alkyl group, a fluoroalkyl group, or an aryl group) in each molecule. The resin structure (A1) and the linear structure (A2) are linked to each other by an Si—O—Si bond, and an Si atom bonded to the resin structure (A1) constitutes an RSiO3/2 unit.

Abstract: The present invention pertains to a curable organopolysiloxane composition comprising at least (A) an organopolysiloxane having at least two alkenyl groups per module, (B) an organopolysiloxane resin represented by average unit formula: (R13SiO1/2)a(R12SiO2/2)b(R2SiO3/2)c(SiO4/2)d. In the formula, R1's are the same or different from each other, and represent a hydrogen atom or a monovalent hydrocarbon group not having an aliphatic unsaturated carbon bond but at least two of the R1's per molecule represent hydrogen atoms, R2 represents a monovalent hydrocarbon group not having an aliphatic unsaturated bond, and a, b, and c are numbers satisfying 0<a<1, 0<b<1, and 0?c?0.2, and 0<d<1, respectively, but are also numbers satisfying 0.6?a/d 1.5, 1.5?b/d?3, and a+b+c+d=1, and (C) a catalyst for hydrosilylation reaction. This composition has excellent adhesiveness to a semiconductor element, and can form a cured product in which only a small number of bubbles are produced.

Abstract: A cosmetic composition and a topical composition containing a resin-linear organopolysiloxane block copolymer are provided, which are excellent in compatibility with other cosmetic raw materials, so as to have a high degree of freedom in formulation design, excellent film forming properties and film following properties, and suppressed tackiness of the film. The resin-linear organopolysiloxane block copolymer contains a resin-linear organopolysiloxane block copolymer (A) having a structure in which a resin structure (A1) block having a siloxane unit represented by R1SiO3/2 (where R1 is a monovalent organic group, a hydroxyl group, or an alkoxy group having 1 to 6 carbon atoms) or by SiO4/2 and a linear structure (A2) block represented by (R2SiO2/2)n (where n is a number of 5 or more, R is an alkyl group, a fluoroalkyl group, or an aryl group) are connected by a Si—O—Si bond and has an R1SiO3/2 unit.

Abstract: A curable silicone composition is disclosed. The composition comprises: (A) an organopolysiloxane having at least two alkenyl groups in a molecule; (B) an organopolysiloxane having at least two silicon atom-bonded hydrogen atoms in a molecule; (C) a polyether-modified silicone comprising repeating units represented by a general formula herein and having a number average molecular weight of 1,000 to 100,000; and (D) a hydrosilylation catalyst. The composition can be used to form an optical semiconductor device having minimal contamination of a case during manufacturing of the optical semiconductor device, good efficiency of light extraction from a light emitting element, and minimal color unevenness or chromaticity deviation. The optical semiconductor device notable in that a light emitting element is sealed or covered by a cured material of the composition, in addition to having minimal contamination of a case, good efficiency of light extraction, and minimal color unevenness or chromaticity deviation.

Abstract: A curable silicone composition comprises: (A) an organopolysiloxane having at least two alkenyl groups in a molecule; (B) an organopolysiloxane having at least two silicon atom-bonded hydrogen atoms in a molecule and free of a polyether structure; (C) a polyether-modified silicone having a siloxane dendron structure and a polyether structure; and (D) a hydrosilylation reaction catalyst. The curable silicone composition can be used to form an optical semiconductor device having minimal contamination of a case during manufacturing of the optical semiconductor device, good efficiency of light extraction from a light emitting element, and minimal color unevenness or chromaticity deviation. The optical semiconductor device is notable in that a light emitting element is sealed or covered by a cured material of the composition, in addition to having minimal contamination of a case, good efficiency of light extraction, and minimal chromaticity deviation.