| 摘要 |
PURPOSE:To provide the above flux composition in which specific carboxylic acid which is evaporated in a soldering stage is adopted as a flux activator and, therefore, substantially no residues remain after soldering and any washing stages are required at all and the electrical reliability required for soldered printed wiring boards is high even when this compsn. is used for packaging of electronic parts. In addition, the solid-components of the flux do not remain in a soldering device and a wiring board carrier and, therefore, the efficiency of the soldering operation is greatly improved. CONSTITUTION:This flux compsn. consists of the volatile aliphat. carboxylic acid and volatile org. solvent. The m.p. of the volatile aliphat. carboxylic acid is <=35 deg.C and the b.p. thereof is >=150 deg.C and <=300 deg.C. |
