PCB板化学镀用低质量浓度盐基胶体钯的研究

通过考察PdCl2质量浓度、n(Sn)/n(Pd)、反应温度、NaCl质量浓度对盐基胶体钯活性和稳定性的影响,确定了PCB板化学镀用的低质量浓度盐基胶体钯制备条件为PdCl2质量浓度0.4 g/L、n(Sn)/n(Pd)=30、反应温度(60±2)℃、NaCl质量浓度160 g/L。依据上述条件配制得到的活化液中,又分别添加了锡酸钠、尿素、香兰素和抗坏血酸4种添加剂,并分析了它们对活化液活性和稳定性的影响。结果表明,尿素在提高活化液的活性和稳定性方面有很好的效果。尿素适宜最低质量浓度为10～15 g/L。

Study on Salt-based Colloid Palladium of Low Mass Concentration for the PCB Electroless Plating

By analyzing the effect of the PdCl2 mass concentration,n(Sn)/n(Pd),reaction temperature,and NaCl mass concentration on the activity and stability of colloidal palladium,the optimal preparation conditions of salt-based colloid palladium of low concentration for the PCB electroless plating were identified,that is,the mass concentrations of PdCl2 and NaCl are 0.4 g/L and 160 g/L respectively,molar ratio of n(Sn)∶ n(Pd) is 30∶ 1,reaction temperature is(60±2) ℃.Four different additives(tin sodium,urea,vanillin,and ascorbic acid) were respectively added into the activation solution obtained under the above-mentioned conditions.The effect of the four different additives on the activity and stability of the activation solution was investigated.The results show that the urea has a good effect on improving the activity and stability of the activation solution.The suitable minimum mass concentration of urea is 10～15 g/L.