SOLDER COMPOSITION ANALYSIS METHOD AND ACID LIQUID FOR SOLVER DISSOLUTION

摘要

PROBLEM TO BE SOLVED: To provide a method for analyzing various elements included in a lead-free solder.SOLUTION: A solder composition analysis method of the present invention includes a step (solder dissolution step) (a) of dissolving a solder into a mixed acid including a sulfuric acid, a nitric acid, and a hydrofluoric acid and a step (analysis step) (b) of analyzing composition components of the solder by quantitative analysis of a dissolved liquid obtained in the step (a). As for the mixed acid, a mixed acid can be used where a sulfuric acid concentration is equal to or more than 3.6 mol/L and equal to or less than 13.4 mol/L, a nitric acid concentration is equal to or more than 1.3 mol/L and equal to or less than 3.4 mol/L, a hydrofluoric acid concentration is equal to or more than 0.53 mol/L, and a mol ratio of the sulfuric acid and the nitric acid is equal to or higher than 2.6:1 and equal to or lower than 7.9:1. By this method, a Ge content of a lead-free solder can be analyzed when the lead-free solder contains Ge.