Catalysing base material when mfg. printed circuit boards - where catalyst soln. contains organic solvent improving adhesion of metal applied by electroless plating

摘要

The catalytic treatment employs a mixt. of a conventional catalyst soln. (A) and an organic solvent (B) which causes swelling of the surface of the board. The pref. mixt. employs a soln. (A) in water of HCl and a colloidal noble metal; plus one or more solvents (B) miscible with water and causing the polymer in the base material to swell. The treatment is pref. employed at an increased temp. esp. at 40'C; and the base material is pref. covered with a layer assisting adhesion prior to the treatment with mixt. (AB). Conventional methods of mfg. printed circuit boards include surface roughening of the board by a chemical treatment with oxidants, e.g. CrO3; but such oxidants cause environmental pollution when discharged into drains. The invention eliminates this chemical treatment, because the swelling aids the adhesion of metal deposited on the board.