Cross-linkable silicone composition and cross-linked product thereof

A cross-linkable silicone composition comprising at least the following components:

• (A) an organopolysiloxane represented by the following average unit formula:
• (R13SiO1/2)a(R12SiO2/2)b(R1SiO3/2)c(SiO4/2)d(R2O1/2)e
• where R1 are phenyl groups, alkyl or cycloalkyl groups having 1 to 6 carbon atoms, or alkenyl groups having 2 to 6 carbon atoms, and where 60 to 80 mole % of R1 are phenyl groups and 10 to 20 mole % of R1 are alkenyl groups;
• R2 is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms;
• and “a”, “b”, “c”, “d”, and “e” are numbers that satisfy the following conditions:
• 0≦a≦0.2;
• 0.2≦b≦0.7;
• 0.2≦c≦0.6;
• 0≦d≦0.2;
• 0≦e≦0.1;
• and a+b+c+d=1;
• (B) an organopolysiloxane represented by the following general formula:
• R33SiO(R32SiO)mSiR33
• where R3 are phenyl groups, alkyl or cycloalkyl groups having 1 to 6 carbon atoms, or alkenyl groups having 2 to 6 carbon atoms, and where 40 to 70 mole % of R3 are phenyl groups and at least one R3 is an alkenyl group;
• and “m” is an integer in the range of 5 to 100, wherein component (B) is used in an amount of 0 to 20 parts by weight per 100 parts by weight of component (A);
• (C) an organopolysiloxane having in one molecule two silicon-bonded hydrogen atoms and where phenyl groups constitute 30 to 70 mole % of silicon-bonded organic groups and where the mole ratio of silicon-bonded hydrogen atoms contained in this component to the total sum of alkenyl groups contained in components (A) and (B) is in the range of 0.5 to 2;
• and
• (D) a hydrosilylation catalyst in an amount sufficient to promote a hydrosilylation reaction between the alkenyl groups contained in components (A) and (B) and silicon-bonded hydrogen atoms contained in component (C).