Storage stable organopolysiloxane gels, preparable in commercial quantities are prepared by the hydrosilylation reaction of a silicone resin containing a hydrosilyatable group, a short chain Si—H-functional silicone, and a long chain Si—H-functional silicone.

A method for producing a coated substrate includes applying a photocurable silicon-containing coating film-forming composition to an uneven substrate; and exposing the photocurable silicon-containing coating film-forming composition to light, wherein the photocurable silicon-containing coating film-forming composition comprises a hydrolyzable silane, a hydrolysate thereof, or a hydrolytic condensate thereof, wherein the hydrolyzable silane is a hydrolyzable silane of the following Formula (1):

R.sup.1.sub.aR.sup.2.sub.bSi(R.sup.3).sub.4−(a+b)  Formula (1)

wherein R.sup.1 is a functional group relating to photocrosslinking; R.sup.2 is an alkyl group and is bonded to a silicon atom via an Si—C bond; R.sup.3 is an alkoxy group, an acyloxy group, or a halogen group; a is an integer of 1; b is an integer of 0 to 2; and a+b is an integer of 1 to 3.

The present disclosure provides an adhesive composition including a silicone-based adhesive and cellulose nanocrystals dispersed in the silicone-based adhesive. The present disclosure also provides an article including a substrate and a layer of the adhesive composition adhered to the substrate. Further, the present disclosure provides a method of making an adhesive composition. The method comprises mixing cellulose nanocrystals in a silicone-based adhesive to disperse the cellulose nanocrystals. The present disclosure additionally provides a method of making an article including disposing a layer of the adhesive composition on a substrate. The presence of the cellulose nanocrystals advantageously increases the water uptake capacity of the silicone-based adhesive while maintaining acceptable adhesive performance.

An elastomer has the general structure of: ##STR00001##
where: subscript a is 50-500, b is 1-10, c is 2-30, R.sup.1 has the structure:
—CH.sub.2(CH.sub.2).sub.nO(CH.sub.2).sub.pCH(OH)(CH.sub.2).sub.qNR.sup.2R.sup.2′ where n, p and q are each independently 1-5 and R.sup.2 and R.sup.2′ are independently selected from alkyl and hydroxyalkyl groups having 1-5 carbon atoms; where X is a crosslinker remnant bound to a siloxane unit corresponding to subscript c of a siloxane backbone polymer in addition to the one shown so that the crosslinker remnant in each occurrence is a reaction product with two siloxane backbone polymers, wherein the crosslinker is selected from a group consisting of primary organic dienes, divinyl siloxane and polyoxyalkylenes wherein at least two X components correspond to crosslinker remnants connecting the same two siloxane backbone polymers.

Described herein is a multi-layered composite including a substrate, an adhesive layer and a top coat layer, the top coat layer being formed by a silicone coating composition including: (A) at least one organopolysiloxane polymer having at least two alkene functions; (B) at least one cross-linking organohydrogensiloxane having at least two Si—H groups; and (C) a catalyst capable of promoting the reaction between component (A) and component (B); wherein the component (B) contains at least 25%, preferably at least 30%, more preferably at least 45% by weight of component (B) of a three-dimensional net-like organohydrogensiloxane resin (B′) containing at least two different units selected from a group including: units M of formula R′.sub.3SiO.sub.1/2; units D of formula R′.sub.2SiO.sub.2/2; units T of formula R′SiO.sub.3/2; and units Q of formula SiO.sub.4/2, wherein R′ represents hydrogen atom or a monovalent hydrocarbonyl group having from 1 to 20 carbon atoms, and with the proviso that at least one of these units is the unit T or Q, preferably Q, and at least one of the units M, D and T comprises a hydrogen atom. Also described, are embodiments where the multi-layered composite has a surface with excellent abrasive resistance and good mechanical properties.

A preparation method for a spherical silica powder filler, comprises the following steps: S1, providing spherical polysiloxane comprising T units by means of a hydrolysis condensation reaction of R.sub.1SiX.sub.3, wherein R.sub.1 is hydrogen atom or an independently selectable organic group having 1 to 18 carbon atoms, X is a hydrolyzable group, and the T unit is R.sub.1SiO.sub.3—; and S2, calcining the spherical polysiloxane under the condition of a dry oxidizing gas atmosphere at a calcining temperature between 850° C. and 1200° C., so as to obtain a spherical silica powder filler having a low hydroxyl content. The spherical silica powder filler is composed of at least one selected from Q.sub.1 unit, Q.sub.2 unit, Q.sub.3 unit and Q.sub.4 unit, wherein Q.sub.1 unit is Si(OH).sub.3O—, Q.sub.2 unit is Si(OH).sub.2O.sub.2—,Q.sub.3 unit is SiOHO.sub.3—, Q.sub.4 unit is SiO.sub.4—, and the content of Q.sub.4 unit is greater than or equal to 95%.

The present invention provides a semiconductor substrate cleaning method including a step of removing an adhesive layer provided on a semiconductor substrate by use of a remover composition, wherein the remover composition contains a solvent but no salt; and the solvent includes an organic solvent represented by formula (L) (wherein each of L.sup.1 and L.sup.2 represents a C2 to C4 alkyl group, and L.sup.3 represents O or S) in an amount of 80 mass % or more.

L.sup.1-L.sup.3-L.sup.2(L)

Provided is a hot-melt curable silicone composition that forms a cured product that can be cured at a temperature of 100° C. or lower, has excellent storage stability, is relatively hard from curing, and has low surface tack, and a sheet or film formed from the same. The curable silicone composition comprises: (A) a solid organopolysiloxane resin that contains at a mass ratio of 0:100 to 90:10 (Al) an organopolysiloxane resin having a curing reactive functional group and containing 20 mol % or more of a Q unit (i.e., a SiO.sub.4/2 unit), and (A2) an organopolysiloxane resin not having a curing reactive functional group and containing 20 mol % or more of a Q unit; (B) 10 to 100 parts by mass of a straight-chain or branched branched chain organopolysiloxane having a curing reactive functional group and is liquid or has plasticity; (C) an organohydrogenpolysiloxane; and (D) a photoactivated hydrosilylation reaction catalyst.

This organopolysiloxane which has a constituent unit represented by general formula (1) and a group represented by general formula (2), said group being directly bonded to a silicon atom, enables a curable composition containing a polyisocyanate compound to achieve a good balance between fast curing properties and storage stability, and enables the achievement of a cured product that has excellent hardness, heat resistance and wet heat resistance.

##STR00001##

(In formula (1), each of R.sup.1A and R.sup.1B independently represents a hydrogen atom, an alkyl group having from 1 to 10 carbon atoms, or an aryl group having from 6 to 10 carbon atoms; and A.sup.1 represents an unsubstituted or substituted divalent hydrocarbon group having from 1 to 20 carbon atoms and optionally having a hetero atom.)

R.sup.2O—  (2)

(In formula (2), R.sup.2 represents a hydrogen atom, an unsubstituted or substituted alkyl group having from 1 to 10 carbon atoms, or an unsubstituted or substituted aryl group having from 6 to 10 carbon atoms.)

A room-temperature-curable organopolysiloxane composition comprising (A) an organopolysiloxane resin which contains silanol groups in a specified amount and has a specified molecular weight and a specified three-dimensional net-like structure, (B) a hydrolyzable organosilane compound containing an organooxymethyl group and/or a partial hydrolysis-condensation product thereof, (C) a linear diorganopolysiloxane of which each molecule chain terminal is capped with a silanol group, and (D) a hydrolyzable to organosilane containing an amino group and/or a partial hydrolysis-condensation product thereof at specified content ratios can be produced easily and at low cost, and can be formed into a high-hardness cured article or coating film even when a metal compound that can serve as a condensation catalyst is not contained.