CROSSLINKABLE SILICON COMPOSITION FOR PRODUCING NON-STICK COATINGS FOR POLYMER FILMS

摘要

This invention concerns cross-linkable silicon compositions that can be used, in particular, to form coatings or water repellent and non-stick film preferably for flexible supports such as synthetic or natural polymer films, for example PET. These compositions are of the types which include crosslinking polyorganosiloxanes bearing Si-H units and unsaturated polyorganosiloxanes preferably containing vinyl, capable of reacting with the crosslinking agent by addition reaction in the presence of platinum to form a release crosslinked non-stick coat on the flexible support. The aim is to propose new liquid coating silicon compositions with no solvents, crosslinkable and non-stick and/or water repellent coating for flexible supports, quasi instantaneous and producing crosslinkable silicon coating of very high quality, in particular with regard to hook/tackiness on a ' high rub-off ' support and anti-stick feature (sufficient high-speed breakaway force). To reach this goal, the invention proposes silicon compositions with the silicon compound ingredient A alcenylated PolyOrganoSiloxane (POS) containing an F1 fraction and an F2 fraction that are different from each other; F2, the adherence enhancer comprising a linear monoalcenylated silicon oil (A_2.1) at one of its ends and/or a long linear a,?, -alcenylated silicon oil (A_2.2) and/or a 'weakly alcenylated linear oil. Applications: non-stick silicon coatings obtained from crosslinking/polyaddition for PET.