To realize a die casting die where, when a die casting die is cooled with cooling water, high water cooling effect can be obtained in a part having a high die surface temperature, and cooling water can be quickly dried in a part having a low die surface temperature.

The cavity face 12 of the die casting die 2 is covered with a hydrophilic surface treatment layer 28, thus a Leidenfrost phenomenon is prevented, and a water film of cooling water 22 widely spreading to the surface treatment layer 28 can be formed. The cavity face 12 can be uniformly cooled. By covering a parting plane 18 with a hydrophobic surface treatment layer 24, the cooling water 22 is repelled at the parting plane 18, thus the time taken for drying can be shortened. Since the time required for the cooling and the time required for the drying in the die casting die 2 can be shortened, a precise die-cast product can be mass-produced in a short period of time.

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