Cover-gasket assembly for hard disk device

Claim 1

A cover-gasket assembly for a hard disk device, comprising a gasket applied to a predetermined position of a cover for the hard disk device, wherein said gasket is formed essentially of a cured product of a liquid fluorosilicone rubber composition having a water vapor permeability coefficient of 40 g.mm/m 2 .24 hr or below, wherein said liquid fluorosilicone rubber composition comprises: (a) a fluorine-containing diorganopolysiloxane having the following general formula (1): ##STR7## wherein R 1 and R 2 may be the same or different from each other and are each an unsubstituted or substituted monovalent hydrocarbon group which does not have aliphatic unsaturated bonds, R 3 is a monovalent aliphatic unsaturated hydrocarbon group, R 4 is a divalent hydrocarbon group having no aliphatic unsaturated bonds or is a group represented by the following general formula (2): --R.sup.5 --O--R.sup.6 -- (2) wherein R 5 and R 6 are each a divalent hydrocarbon group having no aliphatic unsaturated bonds, Rf is a perfluoroalkyl group of from 4 to 10 carbon atoms or a perfluoroalkyl ether group of from 5 to 15 carbon atoms, X is a hydrogen atom or a group represented by the following general formula (3): --Si(R.sup.7).sub.3 (3) wherein R 7 may be the same or different from each other and are each an unsubstituted or substituted monovalent hydrocarbon group, l and m are each an integer of 1 or above, and n is an integer of 0 or above, and further, wherein said fluorine-containing diorganopolysiloxane comprises cyclic siloxanes having a molecular weight of 3,000 or below in a concentration of 0.01% by weight or below; (b) a filler; and (c) a curing agent.