| 摘要 |
PROBLEM TO BE SOLVED: To suppress or prevent discoloring of an aluminum material having excellent rust resistance. SOLUTION: This cooling solution composition contains a freezing point depressant comprising at least either one of an alcohol or a glycol as an effective ingredient and a non-alkanol amine salt-based rust preventing agent, further, 0.00005-0.05 wt.% magnesium compound expressed in terms of Mg and 0.01-1.0 wt.% 2-phosphonobutane-1,2,4-tricarboxylic acid based on the whole weight of the cooling solution. |
