To obtain the subject highly durable mold release agent having excellent mold adhesion and heat resistance and capable of resisting to many shots by dispersing a specific powdery material such as boron nitride powder in the solution of a specified resin such as a polyamideimide.
This mold release agent is obtained by dispersing one or more kinds of powdery materials selected from the group of boron nitride, mica, molybdenum disulfide, and graphite in the solution of one or more kinds of resins selected form the group consisting of polyamideimides, polybenzimidazoles and polyimides. The mold release powder preferably has an average particle diameter of 0.1-30 μm, and the mold release agent powder and the dispersing medium are preferably mixed in a weight ratio of 0.5:9.5 to 4:6, especially 1:9 to 3:7.
HIROKAWA YOSHIYUKI
OGAWA TADASHI
