Abstract: A method for the preparation of a powder mixture of cured silicone microparticles and inorganic microparticles is disclosed, said method comprising (I) forming a water-based suspension of (A) a plurality of cured silicone microparticles having an average diameter of 0.1 to 200 micrometers, (B) a plurality of inorganic microparticles having an average particle diameter of 0.1 to 200 micrometers and, optionally, (C) at least one surfactant; and (II) removing the water from said water-based suspension. The resultant powder mixture is relatively free from agglomeration and may be easily dispersed in organic resins to form a homogeneous mixture for such applications as paints and coatings.

Abstract: The present invention relates to a silicone rubber microsuspension which has an excellent high-concentration storage stability, and to a method for the preparation of a silicone rubber microsuspension. The silicone rubber microsuspension comprises a microparticulate silicone rubber having an average particle diameter not exceeding 10 micrometers, a nonionic surfactant whose HLB value is less than 10, a nonionic surfactant whose HLB value is at least 10, and water, with the proviso that the content of the microparticulate silicone rubber in the silicone rubber microsuspension is at least 50 weight percent. The method for the preparation of said silicone rubber microsuspension comprises mixing a liquid silicone rubber composition, a nonionic surfactant having an HLB value of less than 10, a nonionic surfactant having an HLB value of at least 10, and water.

Abstract: The present invention pertains to a curable silicone composition comprised of (A) an organopolysiloxane represented by the formula ##STR1## wherein R.sup.1 is a monovalent hydrocarbon group other than an alkenyl group; R.sup.2 is a monovalent hydrocarbon group other than an alkenyl group or hydrogen; R.sup.3 is an organic group that contains an epoxy group or an alkoxysilylalkyl group with the proviso that at least one R.sup.3 group is an organic group containing an epoxy group; a is either 0 or a positive number; b is a positive number; c is a positive number; a/c has a value of between 0 to 4, b/c has a value of between 0.05 to 4, and (a+b)/c has a value of between 0.2 to 4; and (B) a curing compound selected from curing agents or curing catalysts. The curable silicone composition of the present invention has superior curing properties and is capable of forming a hardened silicone material with superior flexibility and heat resistance after curing.

Abstract: A diorganosiloxane polymer suitable for modifying thermosetting resins and its preparation are disclosed, said polymer being terminated at each molecular end with an epoxy group-containing organopolysiloxane residue of the following general formula ##STR1## wherein R.sup.1 is a monovalent hydrocarbon group free of alkenyl groups, R.sup.2 is selected from the group consisting of hydrogen and a monovalent hydrocarbon group free of alkenyl groups, R.sup.3 is a monovalent group selected from the group consisting of an epoxy group-containing organic group and an alkoxysilylalkyl group, with the proviso that at least one R.sup.3 group is an epoxy group-containing organic group, R.sup.4 is a divalent hydrocarbon group, a is zero or a positive number, b is a positive number, c is a positive number, a/c is a positive number in the range of zero to 4, b/c is a positive number in the range of 0.05 to 4, and (a+b)/c is a positive number in the range of 0.2 to 4.

Abstract: An MQ organopolysiloxane compatible with organic plastics, has an epoxy-containing organic group, and has the following general formula ##STR1## R.sup.1 represents monovalent hydrocarbon groups, R.sup.2 represents the hydrogen atom and monovalent hydrocarbon groups, R.sup.3 represents epoxy-containing organic groups and alkoxysilylalkyl groups, a is 0 or a positive number, b and c are positive numbers, a/c has a value of 0 to 4, b/c has a value of 0.05 to 4, and (a+b)/c has a value of 0.2 to 4. Also, a method for the preparation of this organopolysiloxane comprises an addition reaction of an Si-H containing organopolysiloxane with an epoxy-containing compound in the presence of a hydrosilylation catalyst.

Abstract: An organopolysiloxane having monofunctional siloxane units (M unit) and tetrafunctional siloxane units (Q unit) and also having in the molecule an epoxy group-containing organic group, a polydiorganosiloxane residue bonded therein across a divalent hydrocarbon group, and optionally alkoxysilylalkyl is useful as an internal stress-relaxing agent, an internal mold-release, and as an adhesion promoter for curable organopolysiloxanes. These organopolysiloxanes are made by an addition reaction.

Abstract: The curable resin composition of the present invention consists of a curable resin having uniformly dispersed therein particles of a cured silicone rubber obtained from an organosiloxane composition curable by a platinum-catalyzed hydrosilation reaction, wherein said organosiloxane composition contains reaction products of an ethylenically unsaturated epoxy compound and an ethylenically unsaturated aromatic compound with the organohydrogenpolysiloxane present in said organosiloxane composition. Either or both of the epoxy compound and the aromatic compound can be prereacted with a portion of the silicon-bonded hydrogen atoms of the organohydrogenpolysiloxane.

Abstract: A semiconductor device (1) in which a heat-bondable cured silicone (7) is applied and heat-bonded to the surface of only a predetermined principal portion of the semiconductor device so as not to contact bonding wires (3), flip chip solder portions (8) or beam leads, in order to protect the surface of the principal portion, and a seal layer (6) or (10) is provided after the heat bonding of the cured silicone. The cured silicone (7) is preferably in the form of a film, and a heat-resistant base material (12) may be laminated to one side of the cured silicone. Breaking of bonding wires (3), cracking of solder portions (8) and separation of beam leads do not occur because only the portion to be protected can be protected by coating with the cured silicone (7) and the portion not to be protected is not so coated. Moreover, sisnce there is no contamination caused by a silicone exhalation, the occurrence of a defective bonding and the separation of a sealing resin can be prevented.

Abstract: The curable resin composition of the present invention consists of a curable resin and the spherical microparticles of cured silicone rubber obtained by the curing of an addition reacting silicone rubber composition, wherein the silicone rubber composition also contains an epoxy compound having an aliphatically unsaturated group. Furthermore, because the microparticles are prepared from an aqueous emulsion or aqueous dispersion of the silicone rubber composition, it has an extremely small particle size.

Abstract: Curable thermosetting resin compositions comprise a continuous phase of a curable thermosetting organic or a curable thermosetting silicone resin containing dispersed finely divided particles of a cured composition prepared by reacting 1) an organopolysiloxane, 2) a curing agent for the organopolysiloxane, 3) an alkoxy group-containing organosilicon compound and 4) a compound of aluminum or zirconium where this compound is an alkoxide, phenoxide, carboxylate or a derivative of a beta- dicarbonyl compound or o-hydroxyketone. Ingredients 3) and 4) can be prereacted and the cured composition optionally contains a filler. The presence of ingredients 3) and 4) imparts improved adhesion between the continuous an dispersed phases of the composition.

Abstract: The water permeability of cured thermosetting organic resin compositions is reduced and the dimensional stability of these compositions during molding is improved by the addition to the curable resin composition of a finely divided, cured organosiloxane material prepared from a curable organopolysiloxane, a curing agent for the organopolysiloxane, an optional silica filler and an aromatic hydrocarbon compound containing a substituted benzene ring where the substituent is a monovalent ethylenically unsaturated hydrocarbon radical or an alkenyloxy radical.

Abstract: The adhesion of organopolysiloxane compositions curable by a platinum catalyzed hydrosilation reaction to various substrates, particularly plastics, is improved by the presence in said compositions of (1) an organosilicon compound containing an ethylenically unsaturated group and at least one alkoxy group and (2) at least one member from a specified class of compounds of aluminum or zirconium.

Abstract: Thermosetting resin compositions of the present invention comprises a thermosetting resin and a specified class of cured polyorganosiloxane resins dispersed as extremely fine particles in the thermosetting resin. Moldings and other shaped articles prepared using these compositions are flexible and exhibit small coefficients of thermal expansion and low shrinkage during molding.

Abstract: What is disclosed are thermosetting epoxy resin compositions containing block siloxane copolymers which are used to induce low internal stress in the cured compositions and to provide coefficients of thermal expansion more closely aligned with the coefficients of thermal expansion of the substrates being molded therewith.

Abstract: Provided is a method for preparing a spherical cured product having a diameter of 5 mm or less of a polymer or a polymer composition containing at least 10 wt % of the linear organopolysiloxane blocks represented by the following general formula (1), characterized by curing in an atomized state a curable polymer or a curable polymer composition containing at least 10 wt % of the linear organopolysiloxane blocks represented by the following general formula (1):--R.sub.2 SiO].sub.n (1)wherein R's are the same or different monovalent hydrocarbon groups and n is an integer of 5 or more.

Abstract: What is disclosed are thermosetting epoxy resin compositions containing block siloxane copolymers which are used to induce low internal stress in the cured compositions and to provide coefficients of thermal expansion more closely aligned with the coefficients of thermal expansion of the substrates being molded therewith.