| 摘要 |
PROBLEM TO BE SOLVED: To remarkably restrain the blackening phenomenon developed during storage of a minimized spangle galvanized steel sheet in a warehouse etc. SOLUTION: A manufacturing method of the minimized spangle galvanized steel sheet excellent in the blackening resistance, is executed by atomizing water solution containing a cation and an anion constituting a material (salt) developing the endothermic reaction on the heating-up process 100 deg.C to 500 deg.C and sodium ion as the cation kind and phosphoric acid ion as the anion kind onto the surface of the galvanized layer under unsolidified state to the steel sheet pulled up from the galvanizing bath. As this water solution, the water solution dissolving >=2 g/L ammonium chloride and >=2 g/L disodium hydrogen- phosphate, is suitably used.
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