| 摘要 |
PURPOSE: A trivalent chromium plating solution for glossy black color and a manufacturing method thereof are provided to enable a wide area of glossy plating by employing Fe ion and Co ion as color formers. CONSTITUTION: A trivalent chromium plating solution for glossy black color comprises trivalent a chromium compound of 0.4-0.6M, a complexing agent of 0.8-1.2M, a conductivity agent of 0.8-1.2M, a buffer agent of 0.8-1.2M, a depolarizer of 8-12g/l, an inorganic color former of 2-14g/l, an oxidizer, and a pH regulator(KOH). The complexing agent restricts polyesterification of trivalent chromium in aqueous solution. The conductivity agent enhances the conductivity of the trivalent chromium ion. The buffer agent stabilizes pH of the aqueous solution. The depolarizer restricts the oxidation of trivalent chromium ion into the divalence. The inorganic color former contains Fe ion and Co ion to adjust the brightness and chroma of a glossy black trivalent chromium plating layer. The oxidizer oxidizes metallic ion included in the inorganic color former. [Reference numerals] (AA) Bath composition; (BB) Electrolysis conditions; (CC) Chemical; (EE) Solutions; (FF) Temp.; (GG) Ammonium persulfate; (HH) Current; (II) Cathode; (JJ) Anode; (KK) Agitation; (LL) Cell; (MM) Time; (NN) Plating activating additive
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