METHODS AND APPARATUS FOR BLOW MOLDING USING MICROGRAINED PATTERNS

摘要

A method and apparatus for blow molding articles having a smooth surface finish by using a mold having a surface provided with a micrograined pattern that facilitates the formation of venting passages with the surface of the parison. One embodiment of the micrograined pattern is a series of substantially circular projections (50) arranged in rows to form a network of interconnected channels (52). This network of channels (52) is connected to vent holes (56) formed in the surface of the mold.