SOLDER PASTE

摘要

PROBLEM TO BE SOLVED: To provide solder paste that eliminates plugging of a nozzle suddenly occurring in the case of being used in a discharge method and forms no residue by the decomposition of flux with heating in soldering.SOLUTION: The solder paste is produced by the mixture of solder powder and flux. The flux is a methacrylic acid polymer in the amount that prevents precipitation of solder powder in an ordinary temperature range and decomposes or evaporates in a heating process in soldering. The flux contains at least 1.0 mass% and less than 2.0 mass% of polyalkyl methacrylate, and at least 5.0 mass% and less than 15.0 mass% of amide stearate as a viscosity adjusting agent, and viscosity is 50-150 Pa. s. The content of the flux in the solder paste is preferably at least 11 mass% and less than 13 mass%.