| 摘要 |
PURPOSE:To manufacture a printed wiring board employing an insulating board which have excellent characteristics such as heat-resistant, abrasion-resistant, flexible, insulating and chemical-resistant characteristics which are necessary for the insulating board for the printed wiring board by a method wherein an oxide gel film in which non-electroplating catalyst is dispersed is formed on the insulating board and a circuit pattern is formed on the insulating board. CONSTITUTION:Plating catalyst (Pd) is dispersed in modified alkysilicate varnish whose solvent component is methanol and hardener is added to produce soft biscous solution. The biscous solution is applied to an Al board 1. The Al board 1 is heated to elevate its temperature from a room temperature to 150 deg.C and then subjected to natural cooling to form an insulating film 2. After the catalyst is exposed by polishing the surface of the film 2, a copper film is formed by non-electro copper plating. Then the copper film is etched to form a circuit 3. Then resist 4 for lift-off is applied only to the interlayer connection part of the circuit and a gel film is formed. The resist 4 is removed to form a hole for interlayer connection. The plating catalyst is exposed and, after plating resist for an upper circuit is applied, the interlayer connection and the upper circuit are formed simultaneously to form a double-layer circuit board. |
