亜鉛めっきの表面形態と高分子接着性

抄録

For the purpose of imparting adhesive properties to electroplated zinc surfaces, a trial has been conducted to control the roughness of the deposit surface. It was found that the addition of DTAC (dodecyltrimethylammonium chloride) cation and/or POELA (polyoxyethylenelaurylamine) nonion to the zinc sulfate bath yielded a “fan-shaped” zinc deposit, with a surface unevenness of 7-8μm height. Although POELA is nonionic, it behaved as a cationic surfactant, like DTAC. X-ray diffraction revealed that the fan-shaped zinc deposit was aligned perpendicular to the substrate, which had (1010) preferred orientation. The surface morphology of the fan-shaped zinc deposit has a very close resemblance to that of the zinc phosphate coating that was used prior to coating paints. The adhesive properties of the fan-shaped zinc surface and the zinc phosphate coating in regard to painted coatings were investigated using the Erichsen test, and it was found that the fan-shaped zinc deposit showed excellent adhesive properties nearly equals to those of the zinc phosphate coating. The results are explained in terms of the anchoring effect, which arised from the surface unevenness of the zinc deposits.