摘要 |
Oxide (3) is present in die surface (6) for contact with fluid resin of upper die (1). The oxide (3) contains a metal cation and an ion. Field strength is computed from the valence of metal cation and the ionic radius of ion. Die release property between hardened resin and die surface (6) is evaluated on the basis of given relationship established between the value of field strength and the adhesion strength between hardened resin and die surface (6). Thus, the method of evaluating the die release property between hardened resin and die surface (6) is established. Material of high die release property (3) can be easily provided by the employment of this evaluation method. Further, resin shaping dies with excellent die release property can be obtained by the use of the material of high die release property (3) in the die surface (6) of upper die (1). |