| 摘要 |
<p>A bath, for electrodeposition of bright crack-free palladium coatings, contg. 1-15g/l. Pd as palladium (II) diamino- dinitrite, 10-50g/l. ammonium nitrate and opt. 1-20g/l. complex former, additionally contains 0.05-1g/l. water-soluble deriv. of benzophenone, pref. benzophenone sulphonic acid. Pref. the bath contains EDTA as complex former, has a pH of 6-8 and is used at a current density of 0.5-2A/sq.dm. Addn. of the benzophenone deriv. improves the brightness of the coatings, reduces internal stress in the coatings and allows thicker coatings to be deposited. Additionally the bath can be used at a pH of 6-8 (instead of the usual pH 9) so that ammonia evolution from the bath is reduced.</p> |
