ORGANOSILICONE COMPOSITIONS

摘要

This invention relates to a silicone composition for preparing release layers and to substrates bearing a layer of the composition. Silicone compositions have been used to render adhesive materials nonadherent to substrates. Many of these silicone compositions cannot be used when backings bearing them cannot withstand the heat required to cure the silicone composition or when the silicone composition cannot be adequately anchored to the backing. This invention provides silicone compositions, curable by a hydrosilation reaction, comprising: (a) an organopolysiloxane having at least two ethylenically-unsaturated hydrocarbon groups bonded to the silicon atoms; (b) an organohydrogenpolysiloxane crosslinking agent; (c) an effective amount of a hydrosilation catalyst; and (d) from about 1% to about 75% by weight of a silicone component containing a plurality of ethylenically-unsaturated groups, said groups having from 4 to 12 carbon atoms, wherein in said silicone component, T-units comprise from about 25 to about 90 mole percent of the total number of siloxane units in said silicone component. The composition provides improved anchorage to substrates without appreciably reducing the curing speed or the release characteristics of the coating. 46924-2A. for