vi vinyl and s and t are numbers within a range that satisfies the conditions given above these are organohydrogenpolysiloxanes with the general formula r a h b sio sub 4 a b 2 r c 1 to c 3 alkyl b is a number that provides at least three hydrogen atoms in each molecule and 1 8 u2266 a b u2266 2 3 that have a viscosity at 25 u00b0 c from 1 to 100 000 centipoise and preferably from 100 to 50 000 centipoise and more preferably from 1 000 to 10 000 centipoise the organohydrogenpolysiloxanes can be exemplified by the following structures str3 x and y are numbers within a range that satisfies the conditions given above str4 m and n are numbers within a range that satisfies the conditions given above these polyorganosiloxanes may contain various other substituents as long as the above described compatibility condition is satisfied these other substituents are nonexhaustively exemplified by amino nitro mercapto carboxyl acyl amide glycidoxy aromatic hydrocarbon and c 4 to c 12 alkyl groups the subject polyorganosiloxanes may also be copolymers with for example polyalkylene oxide e g polyethylene oxide or polypropylene oxide and may contain tetrafunctional and or trifunctional units again as along as the.