Patent ID: 7485693

Claim:
A method of bonding a fluorinated elastomer or a fluorinated gel to an inorganic or organic material comprising a step of (1) applying a primer composition comprising the following components (a) to (e) on a surface of the inorganic or organic material: (a) 100 parts by weight of a linear perfluoro polyether compound having at least two alkenyl groups per molecule, a perfluoro polyether backbone having repeating units represented by the formula, —C a F 2a O—, wherein a is an integer of from 1 to 6, and a weight average molecular weight of from 5,000 to 100,000, (b) a fluorine-containing organosiloxane compound having one or more fluorine atoms and at least two SiH bonds per molecule, in such an amount that the molar ratio of the SiH bond in the organosiloxane compound to the alkenyl group in Component (a) ranges from 0.8 to 5.0, (c) a catalytic amount of a hydrosilylation catalyst, (d) 12.5 to 100 parts by weight of 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, and (e) 100 to 10000 parts by weight, per total 100 parts by weight of said components (a), (b), (c) and (d), of an organic solvent having a fluorine atom and a boiling point of not higher than 150° C. at atmospheric pressures, (2) drying or curing the applied primer composition, (3) applying a heat curable fluorinated elastomer composition or a heat curable fluorinated gel composition on the dried or cured primer composition, and (4) curing the applied heat curable fluorinated elastomer or gel composition.