Patent ID: 7316991

Claim:
A composition, comprising components A, B, C and D in which: A is a first solid hydrophobic material which is insoluble in an organic solvent selected from light fractions of petroleum, acetone, gasoil, hexane, and benzene; wherein component A is a silicon based material formed by the reaction of a starting material comprising from 80% to 100% silicon dioxide with a compound of the formula (I): R 2 SiX 2 (I) wherein R is C 1 -C 6 alkyl, C 2 -C 6 alkenyl, C 2 -C 6 alkynyl, phenyl or benzyl, any of which may be substituted with chloro, fluoro, bromo or nitro; and X is chloro, fluoro, or bromo; B is a second hydrophobic material which is either soluble in or can be emulsified with an organic solvent selected from light fractions of petroleum, acetone, gasoil, hexane, and benzene; and C is a retention improving material comprising a mineral material; and D is acetone or a non-polar organic solvent.