FLUX FOR LEAD-FREE SOLDER PASTE, AND LEAD-FREE SOLDER PASTE

摘要

PROBLEM TO BE SOLVED: To provide a flux for lead-free solder paste which suppresses corrosion of an electrode while keeping wettability of solder metal and generates a flux residue exhibiting excellent insulating resistivity, in mounting under air atmosphere, and to provide a lead-free solder paste.SOLUTION: A flux for lead-free solder paste contains a rosin base resin (A), an activator (B), a thixotropic agent (C) and a solvent (D), where the (A) component contains a hydride and/or polymerized rosin of acrylated rosin, the (B) component contains amine (b1) and non-halogen aliphatic dibasic acid (b2) having the total carbon atoms of 8 to 12, and a content of the (b2) component is 5-10 wt.% in the total flux component.SELECTED DRAWING: Figure 1