| 摘要 |
PURPOSE:To obtain a small pipe type writing utensil reduced in a change with the elapse of time and having stable lever body sliding force regardless of the kind of ink by constituting a lever body of polyacetal receiving partial cutting in its ether bond by the irradiation with radioactive rays. CONSTITUTION:Duracon U10-01 is molded into a lever body having a diameter of about 0.50mm by an extrusion molding machine having a die with a diameter of about 30mm and a bent deformed part is formed to the lever body by press processing so as to set sliding force to about 5+ or -1g and the processed lever body is subsequently irradiated with gamma-rays. A writing utensil is assembled using this lever body 3. That is, a small pipe 2 is fixed to a tip holder 1 in a protruding state and the lever body 3 protruding by predetermined length from the leading end of the small pipe 2 is inserted in the small pipe 2 in a slidable manner and the rear end thereof is supported by the ink relay core 4 inserted from the rear of the tip holder 1 to be fixed to the holder 1 and the ink relay core 4 is connected to the ink chamber in a shaft cylinder not shown in a drawing. Commercial aqueous dye ink is received in the ink chamber to be made writable. |
