The present invention provides a metallocene compound which produces an olefin polymer having a high molecular weight with a high stereoregularity. The control valve includes a first body enclosing the direct-moved shaft, a second body enclosing the diaphragm, a compressive elastic member deformed when the second body is pressed against the first body, and a holder for holding the second body on the first body while the compressive elastic member is deformed by compression. The device can be passed over a body until a RED LED light indicates an effected part needing treatment. In the press sintering step, the resultant mixture is pressure molded under a press pressure of 1 to 4 tcm2 to give a molded article. This advantageously may be done without special optics or special equipment. The medium detection section is attached in the printing section side.