An ultraviolet curable silicone adhesive composition which contains (A) an organopolysiloxane represented by formula (1)

##STR00001##

(wherein each R.sup.1 represents a polymerizable group or a monovalent hydrocarbon group having 1-20 carbon atoms, provided that at least one of the R.sup.1 moieties represents a polymerizable group; R.sup.2 represents an oxygen atom or an alkylene group having 1-20 carbon atoms; and m and n represent numbers satisfying m≥0, n≥1 and 1 (m+n)≥1,000), (B) an organopolysiloxane resin which is composed of (a) an R.sup.3.sub.3SiO.sub.1/2 unit (wherein R.sup.3 represents a monovalent hydrocarbon group having 1-10 carbon atoms) and (b) an SiO.sub.4/2 unit, with the molar ratio of the unit (a) to the unit (b) being 0.6-1.2:1, (C) a fine silica powder and (D) a photopolymerization initiator, and which does not contain a (meth)acrylate compound that does not have a siloxane structure. This ultraviolet curable silicone adhesive composition enables the achievement of a cured product that has good shape retainability and little curing shrinkage, while exhibiting excellent adhesiveness if used as a provisional fixing material.

This composition contains (A) 100 parts of an organopolysiloxane having two groups represented by general formula (1) ##STR00001## (R.sup.1 represents a monovalent hydrocarbon group having 1-20 carbon atoms, R.sup.2 represents an oxygen atom or the like, R.sup.3 represents an acryloyloxyalkyl group or the like, p represents a number satisfying 0≤p≤10, and “a” represents a number satisfying 1≤a≤3) per molecule, (B) 1-500 parts of a monofunctional (meth)acrylate compound not containing a siloxane structure, (C) 1-5,000 parts of an organopolysiloxane resin containing (a) an R.sup.4.sub.3SiO.sub.1/2 unit (in the formula, R.sup.4 represents a monovalent hydrocarbon group having 1-10 carbon atoms) and (b) a SiO.sub.4/2 unit, where the molar ratio of the unit (a) to the unit (b) is in the range of 0.6 to 1.2:1, (D) 1-100 parts of fine powder silica, and (E) 0.01-20 parts of an optical polymerization initiator. The compound has good shape retention properties and curability for irradiation with ultraviolet light, and provides a cured product which has excellent adhesion suitable for a temporary fixing material.

A curable silicone composition comprises (A) a resinous alkenyl group-containing organopolysiloxane including at least two alkenyl groups per molecule and at least one (SiO4/2) unit, (B) a resinous organohydrogenpolysiloxane including at least two silicon atom-bonded hydrogen atoms per molecule and at least one (SiO4/2) unit, (C) a catalyst for hydrosilylation reaction, and (D) a curing reaction inhibitor. The curable silicone composition exhibits practically effective curability even at low temperatures, has a low shape deformation and shrinkage rate during curing, can be cured in a short period of time, and can form a transparent and high-hardness cured product.

An addition-curable liquid silicone rubber composition for LED headlamps, which contains:

(A) (A-1) an alkenyl group-containing liquid organopolysiloxane, and

(A-2) an alkenyl group-containing raw rubber-state organopolysiloxane;

(B) a silicone resin which contains an alkenyl group, while being composed of a unit that is selected from among an R.sup.2.sub.3SiO.sub.1/2 unit (M unit), an SiO.sub.4/2 unit (Q unit), an R.sup.2.sub.2SiO.sub.2/2 unit (D unit) and R.sup.2SiO.sub.3/2 unit (T unit);

(C) an organohydrogen polysiloxane;

(D) a platinum group metal catalyst; and

(E) triallyl isocyanurate.

An addition reaction-curable silicone emulsion composition containing a water-soluble silane coupling agent (I) and an organopolysiloxane (II) having at least two alkenyl groups in one molecule thereof, where the water-soluble silane coupling agent (I) has at least one group selected from among a succinic anhydride group, a quaternary ammonium group, and a ureido group, and 1 part by mass or more of the water-soluble silane coupling agent (I) is contained relative to 100 parts by mass of the organopolysiloxane (II). This provides: a silicone emulsion composition that gives a cured film adhering well to plastic film substrates regardless of the type, while having suitable release properties regarding adhesives; and a delamination film made by forming a cured film of the silicone emulsion composition.

The present disclosures are directed to compositions comprising a polymer having branched silicone substituted by at least one alkylcarboxy group in a free or salt form and cross-linked with an alkyl functional cross-linker, which has the benefits of compatibility with hydrophilic ingredients and particulates in personal care components and the resultant personal care applications.

Organopolysiloxane mixtures curable by hydrosilylation include MT organopolysiloxanes having 10 to 20 siloxy units and containing a fraction of 0.15 to 0.24 M units based on total siloxy units in the organopolysiloxane, and a polydispersity of 1.05 to 1.40, a hydrosilylation catalyst, and an Si—H-functional organopolysiloxane are curable to vulcanizates with elastic moduli which may be greater than 0.5 GPa.

Provided is a method for easily producing a silicone adhesive that has a reduced amount of remaining silanol groups, contains no aromatic hydrocarbon solvent, and is capable of preventing an impact(s) on the human body as well as skin irritancy as caused by remaining and volatilizing substances. The method includes: a first step of mixing, under the presence of a basic catalyst, (A) a polydiorganosiloxane, (B) an organopolysiloxane whose molar ratio of R.sup.1.sub.3SiO.sub.0.5 unit/SiO.sub.2 unit is 0.5 to 1.5, and (C) an aliphatic hydrocarbon solvent; and a second step of treating a product obtained in the first step with an organic disilazane compound and/or a silane compound, for the purpose of lowering an amount of silanol groups contained in a solid product obtained after the treatment to a range of 0.002 to 0.03 mol/100 g of the solid product obtained after the treatment.

Composition of comprising nano metal oxide/hydroxide particles and a polyorganosiloxane having increased refractive index, processes to cure these compositions for making transparent coats, shaped articles by an extrusion or molding process having a refractive index above the refractive index of the polyorganosiloxane. Use of the cured polyorganosiloxane compositions as optical devices, coats, lenses or light guides.

Silicone pressure-sensitive adhesives is the reaction product of a composition including a silanol end group-containing linear organopolysiloxane; a non-functional linear organopolysiloxane; and a silicate resin; wherein the dynamic viscosity of the non-functional linear organopolysiloxane at 25° C. is 100,000 mm.sup.2/sec or greater. The silicone pressure-sensitive adhesive has enhanced adhesion while minimizing skin damage and pain during removal of the adhesive.