JPS5759734A - Method of molding indicating part such as character and pattern in one body on surface of molded article - Google Patents

Abstract

PURPOSE:To avoid the waviness on the surface of an indicating part and prevent the generation of defective article by a method wherein resin pouring holes and overflow holes both of which penetrate through a moled article from the back side of the article to the surface for forming the indicating part are provided on the same forming surface. CONSTITUTION:When a mold 20 for injection molding is closed and a molten resin is poured in, the resin flow through a sprue hole 22 of an upper mold 21, fills up runner grooves of a runner plate 25 and flows into a character forming surface 11 through gate holes 27, 27... and each of the pouring holes 12, 12.... Further, a part of the resin filling the character forming surface is fed under pressure into the overflow holes 13 which are the other groups of through-holes provided for the molded article. In this case, since the overflow holes 13 are provided at the parts where the waviness tend to be formed, namely, at the other ends of the pouring holes 12 or the positions at which the flows of the molten resin join, the resin which has has been poured in first and of which the temperature has been lowered is fed under pressure into the overflow holes 13, so that the resin is not exposed at the surface of the indicating part. Accordingly, the resin for forming the indicating part consists of the resin which has a uniform temperature and does not produce the waviness.