A primer composition for a fluorinated
elastomer or a fluorinated gel, said primer composition comprising:100 parts by weight of (a) a linear perfluoro polyether compound having at least two alkenyl groups per molecule, a perfluoro polyether backbone having repeating units represented by the formula, —CaF2aO—, wherein a is an integer of from 1 to 6, and a weight average molecular weight of from 5,000 to 100,000,(b) an organosiloxane compound having one or more
fluorine atom and at least two SiH bonds per molecule, in such an amount that a
molar ratio of the SiH bond in the organosiloxane compound to the alkenyl group in Component (a) ranges from 0.8 to 5.0,a catalytic amount of (c) a
hydrosilylation catalyst,5 to 100 parts by weight of (d) an organosiloxane compound having, per molecule, at least one SiH bond and at least one
epoxy group and / or trialkoxysilyl group bonded to a
silicon atom of said organosiloxane via an
organic group which may have an
oxygen atom, and100 to 10000 parts by weight, per total 100 parts by weight of said components (a), (b), (c) and (d), of (e) an
organic solvent having a
fluorine atom and a
boiling point of not higher than 150° C. at
atmospheric pressure.