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This additive is a blue liquid. The SN-6-produced bronze color is brilliant, much better than that produced by the conventional Sn-Ni salt, with the same good lightfastness.

1. Bath Composition (For make-up):

SN-6
H₂SO₄
Deionized Water

80-100g/L
15-20g/L
balance

2. Processing Parameters:

Voltage
Temperature
Time

10-20V
20-30℃
1-8min

3. Bath Maintenance:

(1) Analyze the contents of SN-6 Additive and H₂SO₄ daily and make compensation in time if necessary so as to minimize the fluctuation of contents.
(2) During stop-work, the coloring tank has to be covered so as to prevent the contamination with other solution.