INJECTION MOLDING METHOD AND INJECTION MOLDING DIE

PROBLEM TO BE SOLVED: To increase the strength of a fused section generated on an injection molded article by a simple method. SOLUTION: In a filling process of a resin, after a plurality of resin streams have come into contact with each other and fused, at least one gate section is gate-sealed prior to other gate sections. Then, under a state wherein the filling of the resin from the gate-sealed gate section is stopped, the resin is filled in a cavity from other gate sections. Thus, a pressure difference is generated in the filling pressure of the plurality of resin streams which are not hardened yet at the fused section. Then, by utilizing the pressure difference, into one resin stream which forms the fused section, the other resin stream is forced. Thus, the shape of the core layer section of the fused section is changed, and the bonding strength at the fused section is increased.