Patent ID: 9242400
Filing Date: 2016-01-26
CPC Classification: B29C,B29K,B29L,C08L

Claim Text:
1. A resin injection molding method of molding a resin by injection-filling an inside of a mold cavity, which is formed by mold-clamping a pair of design surface mold and non-design surface mold, with a melted thermoplastic polypropylene resin composition, the method comprising: setting a temperature of each of cavity-forming surfaces of the design surface mold and the non-design surface mold prior to the injection filling to 60° C. to 120° C., and setting the temperature of the cavity-forming surface of the design surface mold to be higher than the temperature of the cavity-forming surface of the non-design surface mold by 5° C. to 50° C., and causing the resin pressure to reach to a negative pressure within 7 seconds after completion of the injection filling of the thermoplastic polypropylene resin composition, wherein the thermoplastic polypropylene resin composition contains a crystalline polypropylene resin and a rubber component and a content of the rubber component is 1 mass % to 40 mass %.