| 摘要 |
PURPOSE:To suppress the occurrence of a phenomenon called corrosion such as elution, discoloration or the like of a solder by using a solution prepared by adding a specific imidazole compound to an alkaline aqueous solution. CONSTITUTION:When a plated part, to be exfoliated by an alkali, used to manufacture a through-hole printed-circuit board using the solder plated part as an etching resist is to be exfoliated, an imidazole compound expressed by Formula (1) (where R1 is a hydrogen atom, a cyanoethyl group or an aminoethyl group, R2 is the hydrogen atom, a methyl group or an ethyl group and R3 is the hydrogen atom or the methyl group) is added to an alkaline aqueous solution and the plating resist is exfoliated by using this aqueous solution. The imidazole compound to be used is imidazole, 2-methylimidazole, 2-ethyl-4-methylimidazole or the like; these compounds are normally added to the alkaline aqueous solution within a range of 0.1-1.0wt.%. |
