Patent ID: 7119159

Claim:
An addition-crosslinking silicone composition comprising (A) at least one diorganopolysiloxane of the formula (1) R 1 a R 2 b SiO (4−a−b)/2 (1), in which R 1 is a hydroxyl radical or a monovalent, optionally halogen-substituted C 1-20 hydrocarbon radical optionally containing O, N, S or P atoms, and being free of aliphatically unsaturated groups, R 2 is a monovalent, aliphatically unsaturated, optionally halogen-substituted C 1-10 hydrocarbon radical optionally containing O, N, S or P atoms, a has a value from 1.0 to 2.0, b is from 0.0003 to 2, with the proviso that 1.5<(a+b)<3.0, that on average at least two aliphatically unsaturated radicals R 2 are present per molecule, and that the viscosity of the diorganopolysiloxane(s) (A) is 1 mPa·s to 40,000 Pa·s, determined at 25° C., (B) organohydropolysiloxanes of the general formula (2) R 3 c R 4 d R 5 e H f SiO (4−c−d−2e−f)/2 (2), in which R 3 is a monovalent aliphatically saturated C 1-20 hydrocarbon radical, R 4 is (a) an optionally halogen-substituted monovalent C 6-15 hydrocarbon radical which contains at least one aromatic C 6 ring, or (b) a halogen-substituted, saturated monovalent C 2-20 hydrocarbon radical optionally containing O, N, S or P atoms, R 5 is a bivalent, optionally halogen-substituted C 6-20 hydrocarbon radical Si-bonded at both ends, optionally containing O, N, S or P atoms, c, d, e and f are independently zero or a non-zero number, with the proviso that the organohydropolysiloxane (B) contains on average at least 3 SiH groups per molecule, that the relationship: 0.05<100 (d+e)/(c+d+e+f) is fulfilled, and that the viscosity of the organohydropolysiloxane (B) is 1 mPa·s to 100 Pa·s determined at 25° C., (C) adhesion promoters in which each R 12 independently is a hydrogen atom, a hydroxyl group, a halogen atom, an alkyl, alkenyl, alkoxy, alkenyloxy or aryl group, or a monovalent organic group containing an alkenyl, alkoxy, glycidyl, carbonyl, carbonyloxy, silyloxy or alkoxysilyl group, at least one of the radicals R 12 being an alkenyl group or a monovalent organic group containing an alkenyl group, and X is selected from the following groups: —(R 13 —)C(—R 13 )—, —(O═)S(═O)—, —(O═)S—, —C(═O)—, —O—(CH 3 —)Si(—CH 3 )—O—, —(CH 2 ) s — or —O— in which R 13 is a hydrogen atom, a halogen atom or a substituted or unsubstituted alkyl, aryl, alkenyl or alkynyl group and s is a positive number of at least 2, and r is 0 or 1, and (D) a hydrosilylation catalyst.