PRIMER COMPOSITION

PROBLEM TO BE SOLVED: To provide a primer composition exhibiting sufficient adhesiveness in the construction joint of a PIB (polyisobutylene)-based sealing material on a silicone-based sealing material after the lapse of a long time from the application and imparting a PIB-based sealing material with good adhesiveness to a substrate such as aluminum subjected to electrolytic coloring treatment. SOLUTION: The primer composition is produced by adding a ketimine-based silane coupling agent to a principal primer component composed of a paraffinic plasticizer solution containing a saturated hydrocarbon polymer having an alkylene structure as the main chain structure and having an alkoxysilyl group on the molecular terminal, a polymer having an essentially vinyl copolymer as the main chain structure and having a hydroxy group or a hydrolyzable group bonded to silicon atom on the molecular terminal and/or side chain, an organic solvent, an organic titanic acid ester and an amino-based silane coupling agent. COPYRIGHT: (C)2004,JPO