Various complexing agents for cuprous ions were added to electroless copper plating baths and the effects of the complexing agents on the ductility of copper deposited from the baths were studied.
1) The ductility of deposited copper was improved by the addition of complexing agents having -N=C--C-=N- radicals such as 2-(2-pyridyl)- benzimidazole, 2-(2-pyridyl)- imidazoline, and phenanthroline derivatives.
2) In particular, the addition of 2, 9-dimethyl -1, 10-phenanthroline at 70-90°C was found to deposit copper having markedly improved ductility.
3) The addition of 1, 10-phenanthroline was not effective in improving the ductility, but it deposited an extremely bright copper.
4) The complexing agents having sulfur in their chemical structures such as thiourea, rhodanine, and 2-mercaptobenzothiazole had no effects on the ductility.

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Integrally colored anodic coating of aluminum was obtained by electrolysis in aqueous solution of sulfo-salicylic acid. The properties and micro-structure of the coating were studied by X-ray diffraction and micro-analyses.
The color difference was measured as a function of electrolysis time.
The results obtained were as follows:
1) The oxide coating of sulfo-salicylic acid was observed amorphous by X-ray analysis, but it turned to the structure of γ-Al₂O₃ by heating to about 700°C.
2) The dark brown colored oxide coating of sulfo-salicylic acid turned to pale pink by heating at 700-900°C. Therefore, it was supposed that the color component would consist of some substance changing its color tone by heating at 700-900°C.
The relation between the color difference and the time of electrolysis was expressed by the following equation:
y=17.5 log T-11.5
where y: Color difference (NBS)
T: Time of electrolysis (min.)
The depth of color of the coating increased with time of electrolysis and finally reached saturated state.

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