Preparation of salt-based colloid palladium of high concentration

摘要

A kind of salt-based colloid palladium of high concentration was prepared, with concentration up to 3. 6 g/L on amount of PdCl_2. The optimal preparation conditions of the salt-based colloid palladium were that the PdCl_2 and NaCl concentrations were respectively 3. 6 g/L and 175 g/L, mole ratio of Sn to Pd was 50:1, reaction temperature was 20 -35 deg C, with urea, ascorbic acid and vanillin added in a proper amount. The test results of optimal condition show that the time of starting hydrogen-deposition is 9 s, the time of completely coating copper on a test substrate is 2 min, the stability time of colloid palladium is 98 h after it is diluted into 0. 1 g/L(on amount of PdCl_2) when the solution temperature is 20 deg C , the backlight lever of electroless copper plating layer is 10th grade of 10-grade system, the adhesion force of the copper layer is up to GB5270-85 of China, and the average particle size of the colloid palladium is 81 nm measured by Master Sizer.