| 摘要 |
An aq. alkaline liq. soln. consists of water, at least 75 g/l NaM3O4 and sufficient NaOH for all Mn residueto be removed from the surface of material contacted with the soln. by acid neutralisation. A resinous substrate (e.g. epoxy/fibre glass) is prepd. for metallisation by contacting it with the soln. for desmearing resin from the inside walls of holes, cleaning holes of a multilayer circuit board or etching back the surface of the circuit board. Pref. soln. contains 75-400 (pref. 100-200 esp. 160) g/l NaM3O4 and 40-400 (pref. 40-150, esp. 60) g/l NaOH. The soln. effectively and rapidly removes resin smears and provides controlled etchback e.g. to expose conductors in a multilayer board.
|
