| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of manufacturing a cold rolled steel sheet with superior chemical conversion properties in which generation of an interference color called a blue color is unlikely to occur.SOLUTION: A cold rolled steel sheet manufactured through continuous annealing is brought into contact with an alkaline aqueous solution without acid cleaning, and then washed and dried. It is preferred that the alkaline aqueous solution has pH of 11 or higher, the temperature is 50°C or higher, and the time for contacting is 5 seconds or longer. |
