| 摘要 |
PURPOSE:To improve the roundness of the ultrasonic weld zone between the container main body and a lid and to secure the airtightness of the container by setting >=3 gates at regular intervals at the time of injection-molding the plastic lid for the plastic aerosol container. CONSTITUTION:The plastic container main body 1 and its plastic lid 4 are welded by ultrasonic welding to form the plastic container. In this case, the thick mouth edge 10 of the lid 4 is covered with a metallic mounting cap 3 with an injection nozzle 2 fixed to it, and caulking is applied to engage both members. At this time, a gate part 12 is provided at the lower end of the inner periphery 11 of the edge 10 of the lid 4, and >=3 gates 8 are set substantially at regular intervals in the gate part 12, and the lid is injection-molded. Consequently, the roundness of the inner side of the edge 10 of the lid 4 to be engaged with the cap 3 is improved, the roundness of the ultrasonic weld zone between the main body and lid is improved, and the airtightness of the container is secured. |
