PLASTIC FILTER AND MOLD THEREOF

摘要

PURPOSE:To produce an ultrafine plastic filter by the action equal to that of a guide groove by a method wherein the rib groove forming the rib part of a mold is made deep in a vertical direction in the vicinity of the center part of a filter and made wide in the vicinity of a frame member. CONSTITUTION:An upper mold is formed by a second upper mold core 19 having frame grooves 22 formed thereto and a first upper mold core 17 having vertical rib grooves 14 formed thereto. The frame grooves 22 and the vertical rib grooves 14 are made deep and wide in the center part of a filter as compared with a frame member and the action of a guide grooves is applied so as to make molten plastic easy to flow. A second lower mold core 20 and a first lower mold core 18 both of which have frame grooves 22 and horizontal rib grooves 15 formed thereto in the same way are combined to produce a filter having a reticulated structure. Therefore, molten plastic is allowed to easily and certainly flow in the rib grooves 14, 15 and the frame grooves 22 and even a fine filter can be easily produced.