CLOSE CONTACT OF COATING FILM TO MATERIAL TO BE COATED

摘要

PROBLEM TO BE SOLVED: To enable firm close contact of a coating film to a material to be coated by selecting a kind of coating material and a material to be coated so that the interfacial surface tension between coating film and the material to be coated may be a specific value or below. SOLUTION: An additive (preferably a silane coupling agent) is added to a coating material forming a coating film or a material to be coated is subjected to surface treatment (preferably plasma treatment) so that interfacial surface tensionγSP obtained by using the formula [γS is surface tension of a material to be coated;γSLW is force item between long distances ofγS;γS<+> is an acidic item ofγS;γS<-> is a basic item ofγS and satisfies the relationship of the formulaγS=γSLW+2(γS<+> .γS<-> )<1/2> ;γP is surface tension of coating film;γPLW is force item between long distances ofγP andγ<+> is an acidic item ofγP andγP<-> is a basic item ofγP and satisfies the relationship of the formulaγP=γPLW+2(γP<+> .γP<-> )<1/2> ] may be <=0.0 mJ/m<2> in the interface between the coating film and the material to be coated. Thereby, the coating film is sufficiently brought into close contact with the material to be coated.