| 摘要 |
<p>The invention relates to a process for obtaining artistic patina, by chemical passivation of iron parts surfaces, consisting in successively applying, by brushing, a slightly oxidizing solution containing 0.25 moles/l H3PO4, 5 x 10^(-3) moles/l K2Cr2O7 and/or 5 x 10 ^(-3) moles/l KNO3, 0.08 moles/l ZnHPO4, 0.15 moles/l Zn(NO3)2, 0.15 moles/l Mn(NO3)2 and 1 x 10^(-4) moles/l benythiazole in 10% alcoholic solution and a reducing solution prepared before use and containing 0.3 moles/l H3PO4, 1 x 10^(-2) moles/l CuSO4, 12 x 10^(-3) mole/l formic aldehyde or hydrazine sulphate, the operations being repeated 5 to 20 times, up to obtaining the desired patina.</p> |
