Abstract: Thixotropic, silica-filled coating compositions wherein the curable film-forming material is an organosiloxane copolymer resin include a liquid polydiorganosiloxane containing hydroxyl-terminated polyoxypropylene units as the flow control agent. The compositions are particularly useful as screen printable passivation coatings for semiconductor devices.

Abstract: The combination of (1) a polyorganosiloxane composition curable by a platinum catalyzed hydrosilation reaction with (2) up to about 20 percent, based on the weight of (1), of a polyorganosiloxane composition comprising the mixture of a liquid hydroxyl-terminated polydiorganosiloxane and a moisture reactive organosilicon crosslinking agent, or the reaction product of said mixture, and an organotitanate catalyst yields elastomers that cure rapidly at temperatures of at least about 80 degrees C. and cohesively bond to inorganic substrates such as glass and metal. The resultant cured elastomer exhibits a durometer or less than about 20 on the Shore A durometer scale.

Abstract: Peroxide curable organosiloxane elastomer compositions where from 0.1 to 10 mole percent of the silicon-bonded hydrocarbon radicals are phenyl improve the leakage current resistance of silicon diodes when the compositions are applied to these devices as junction coatings.

Abstract: The degree of thixotropic character exhibited by curable compositions comprising specified epoxide reactants, organosilicon reactants and fillers can be varied by varying the weight ratio of epoxide reactant to organosilicon reactant between values represented by r.sub.1 and r.sub.2 wherein said values are within the range of from 1:1 to 8:1. The compositions are particularly useful as extrudable coatings for solid state electronic devices.

Abstract: The crack resistance of phenyl silicone molding compounds containing siliceous fillers is improved by incorporating therein from 4 to 15 percent by weight based on the combined weight of the resins of an aromatic epoxy resin having an epoxide equivalent of from 475 to 2000. These molding compounds are particularly suitable for encapsulating electronic devices such as diodes.