| abstract |
The present invention provides an aqueous coolant for forming a laminated metal plate DI, which enables DI forming of the laminated metal plate and can provide a laminated DI can excellent in durability and food safety. The aqueous coolant of the present invention is selected from amino acids and polypeptides having a pH of 6.5 to 12 at 50 ° C. when dissolved in an aqueous solution so that the total amount is 0.03 to 1% by mass. It contains 0.03 to 1% by mass in total of one or more selected. And pH in 50 degreeC is 6-8. For example, the amino acid may include one or more selected from histidine, arginine, lysine, oxylysine, and theanine. For example, as said polypeptide, what contains 40 mass% or more of 1 or more types of amino acids chosen from histidine, arginine, lysine, and oxylysine can be used. [Selection figure] None |