| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a method of stably producing a solder alloy fine particle which is in the form of a nano-sized fine particle, has a small particle size distribution, and includes practically no metal fine particles composed of a single metal, and to provide a solder paste which has excellent discharging properties and is applicable to fine wiring boards and so on.SOLUTION: A method of producing a solder alloy fine particle comprises reducing two or more metal salts for a solder alloy with a reductant in the presence of a complex-forming agent, dispersant, and a pH-adjusting agent, in a thin-film fluid formed between treatment surfaces 1 and 2 which are arranged so as to face each other and be capable of approaching and separating from each other and one or both of which are relatively rotatable. A solder paste consisting of the solder alloy fine particle and a solder flux is also provided. Fine particles of the alloy having an average particle size of 10-1,000 nm are deposited. The metal salts comprises those between a plurality of Sn, Bi, Ag, Cu, Sb, Pb, etc. The complex-forming agent is an aliphatic carboxylic acid, an amino carboxylic acid, etc.</p> |
