Silicone compositions that can be crosslinked by irradiation with light, preferably UV light, comprising (A) organosilicon compounds comprising Si-C-bonded radicals having aliphatic carbon-carbon multiple bonds, (B) organosilicon compounds comprising hydrogen atoms bonded to Si or instead of (A) and (B) (C) organosilicon compounds comprising Si-C-bonded radicals having aliphatic carbon-carbon multiple bonds and hydrogen atoms bonded to Si, (D) platinum catalysts that can be activated by light of wavelength 200 to 500 nm, preferably UV light of wavelength 200 to 400 nm, selected from the group of cyclopentadienyl complexes of platinum and (E) organophosphorus compounds selected from the group of the formulae P(=O) u [(OR 10 )] s [R 11 ] t (I), P[(O) i SiR 12 3 ] 3 (II), and mixtures thereof, wherein R 10 and R 11 are the same or different and are in each case an alkyl radical of the formula C j H 2j+1 where j = 2-31 or an alkenyl radical of the formula C k H 2k-1 where k = 2-31 or an aryl or alkylaryl radical of the formula -(C 6 H 5-w ) - (C v H 2v+1 ) w where v = 1-18 and w = 0-5, R 12 is the same or different and is a monovalent hydrocarbon radical having 1 to 18 carbon atoms, R 13 is a tetravalent hydrocarbon radical having 5 to 30 carbon atoms, R 14 is the same or different and has the definition of R 10 , s is 0, 1, 2 or 3, t is 0, 1, 2 or 3, with the proviso that the sum of s+t = 3, u is 0 or 1, preferably 0, and i is 0 or 1, preferably 1. (A) organosilicon compounds comprising Si-C-bonded radicals having aliphatic carbon-carbon multiple bonds, (B) organosilicon compounds comprising hydrogen atoms bonded to Si or instead of (A) and (B) (C) organosilicon compounds comprising Si-C-bonded radicals having aliphatic carbon-carbon multiple bonds and hydrogen atoms bonded to Si, (D) platinum catalysts that can be activated by light of wavelength 200 to 500 nm, preferably UV light of wavelength 200 to 400 nm, selected from the group of cyclopentadienyl complexes of platinum and (E) organophosphorus compounds selected from the group of the formulae P(=O) u [(OR 10 )] s [R 11 ] t (I), P[(O) i SiR 12 3 ] 3 (II), and mixtures thereof, wherein R 10 and R 11 are the same or different and are in each case an alkyl radical of the formula C j H 2j+1 where j = 2-31 or an alkenyl radical of the formula C k H 2k-1 where k = 2-31 or an aryl or alkylaryl radical of the formula -(C 6 H 5-w ) - (C v H 2v+1 ) w where v = 1-18 and w = 0-5, R 12 is the same or different and is a monovalent hydrocarbon radical having 1 to 18 carbon atoms, R 13 is a tetravalent hydrocarbon radical having 5 to 30 carbon atoms, R 14 is the same or different and has the definition of R 10 , s is 0, 1, 2 or 3, t is 0, 1, 2 or 3, with the proviso that the sum of s+t = 3, u is 0 or 1, preferably 0, and i is 0 or 1, preferably 1. R 10 and R 11 are the same or different and are in each case an alkyl radical of the formula C j H 2j+1 where j = 2-31 or an alkenyl radical of the formula C k H 2k-1 where k = 2-31 or an aryl or alkylaryl radical of the formula -(C 6 H 5-w ) - (C v H 2v+1 ) w where v = 1-18 and w = 0-5, R 12 is the same or different and is a monovalent hydrocarbon radical having 1 to 18 carbon atoms, R 13 is a tetravalent hydrocarbon radical having 5 to 30 carbon atoms, R 14 is the same or different and has the definition of R 10 , s is 0, 1, 2 or 3, t is 0, 1, 2 or 3, with the proviso that the sum of s+t = 3, u is 0 or 1, preferably 0, and i is 0 or 1, preferably 1. <EOS>