| 摘要 |
PROBLEM TO BE SOLVED: To obtain a galvanized steel sheet for an organic resin-coated steel sheet excellent in adhesion even in the case organic resin coating having specified coating thickness is formed by regulating the difference between the highest point and the lowest point of the ruggedness of the surface roughness and Ra of a galvanized steel sheet in which chromate coating is formed to specified ranges. SOLUTION: By regulating the difference between the highest point and the lowest point of the ruggedness of the surface roughness of a galvanized steel sheet in which chromate coating is formed to 200 to 600 nm and regulating Ra to 30 to 100 nm, a galvanized steel sheet excellent in adhesion even at the time of forming organic resin coating having >=100μm coating thickness can be obtd. Furthermore, by regulating the specific surface area therein measured by a BET method to 4.0 to 16.0 by the ratio to the specific surface area before chromate treatment, its adhesion can be improved. Moreover, in the X-ray image of metals in metallic oxides obtainable by X-ray irradiation, in the case the ratio in which the region of more than the intermediate value between the maximum value and the minimum value of the X-ray intensity occupies in the measured region is defined as a coating ratio by the whole metallic oxides, the coating ratio is regulated to 60 to 100%, by which its adhesion improves.
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