Patent ID: 8058381

Claim:
A method for producing a liquid curable fluorosilicone composition comprising (A) 100 parts by weight of an organopolysiloxane having a viscosity at 25Â° C. of 100 to 500,000 mPaÂ·s and represented by the following average compositional formula: (CF 3 CH 2 CH 2 ) a R b SiO (4-a-b)/2 wherein R is a monovalent hydrocarbon group of 1 to 8 carbon atoms with the proviso that at least 0.001% by mole is an alkenyl group, a is 0.1 to 1.0, b is 2.5 to 1.0, and a+b is 1.8 to 3.0, (B) an organohydrogenpolysiloxane containing at least 2 hydrogen atoms bonded to the silicon atom in a molecule in an amount such that number of the hydrogen atom bonded to the silicon atom in the component (B) is 0.5 to 10 per one alkenyl group bonded to the silicon atom in the component (A), and (C) an catalytic amount of an addition catalyst, said method comprising adding (D) a diorganopolysiloxane having a viscosity at 25Â° C. of 1 to 10,000 mPaÂ·s represented by the following formula: wherein Me is methyl group, q is an integer of at least 1 with the proviso that q is a number such that the viscosity of the composition at 25Â° C. is in the range of 1 to 10,000 mPaÂ·s as a defoaming agent to the components (A) to (C) in an amount of 0.001 to 5 parts by weight per 100 parts by weight of component (A), and after its addition, defoaming the composition in a defoaming device.