| 摘要 |
PURPOSE:To minimize blow holes and uneven surface of a product by keeping the pressure in a mold at the pressure equal to or higher than the pressure raised by injection, until the polymerizing and forming of raw material are finished, while injecting the raw material into the mold which is pressurized to 0.5-20kg/cm<2>.G by inert gas. CONSTITUTION:A metal mold 1 is pressurized to 0.5-20kg/cm<2>.G by the inert gas supplied through a pipe 11, a gas trap 2 and a pipe 12. Molten omega-lactam is supplied to a mixing head 4 through a pipe 13 and a pipe 14, and injected into the cavity 5 of the metal mold 1. Through the polymerizing and forming of the omega-lactam is achieved in the cavity 5, the pressure in the metal mold 1 is raised by injecting the raw material into the cavity 5. Then, the pressure in the metal mold 1 is prevented from excess rising, as the cavity 5 and the gas trap 2 are connected through the pipe 12. |
