abstract |
Formula (1)n n n n n n n n Wherein R 1 represents a hydrogen atom or a methyl group. When R 2 and R 3 are chlorine atoms, R 4 and R 5 represent hydrogen atoms, and when R 2 and R 3 are hydrogen atoms, R 4 and R 5 represents a chlorine atom.) An aqueous composition for surface treatment of copper or copper alloy for soldering using a lead-free solder. |