PURPOSE: To improve the uniformity of image quality by providing a stagnating part in the longitudinal direction of a metallic mold for orientation.

CONSTITUTION: In a vertical type injection molding machine 1, a pellet material is formed by using the metallic mold 5 constituted of a magnetic material 3 which forms magnetic paths from the central part of a circular arc to other three sides by a lower magnetic material 3b having a fan-shaped recessed part 3a a T-shaped upper magnetic material 3c in a coil, and non-magnetic material 4 which surrounds a part excepting the upper part of both sides of the fan shape and the central part of the circular arc surface. The axis of easy magnetization of the ferrite particle is oriented in the direction of the line of magnetic force by electric field generated by energizing the coil 2 to obtain a pole piece whose cross section is fan-shaped and which is oriented from the central part of the circular arc to the other three sides. Thus, the uniformity of the image quality all over the surface is realized.