Method of manufacturing resin mold product

A method for manufacturing a resin molded article made of a high impact polystyrene, which is a polymer blend of a styrene graft butadiene copolymer, and a styrenic polymer, or a polymer alloy or polymer blend containing said high impact polystyrene, comprising;

• the preparation of a mold whose cavity is designed to set X direction, Y direction, and Z direction molding shrinkage ratios of said resin molded article to be the same value each into a range of between 4.5/1000 and 6.7/1000, the injecting of said high impact polystyrene, or said polymer alloy or polymer blend containing said high impact polystyrene, into said mold cavity, said high impact polystyrene, or said polymer alloy or polymer blend containing said high impact polystyrene, being melted by heating at a temperature higher than 160° C., and then the injecting of a fluid at a pressure higher than the atmospheric pressure during, or after the injection of said high impact polystyrene, or said polymer alloy or polymer blend containing said high impact polystyrene.

A method for manufacturing a resin molded article made of a modified polyphenylene ether, or a polymer alloy or polymer blend containing said modified polyphenylene ether, comprising;

• the preparation of a mold whose cavity is designed to set X direction, Y direction, and Z direction molding shrinkage ratios of said resin molded article to be the same value each into a range of between 4.5/1000 and 6.5/1000, the injecting of said modified polyphenylene ether, or said polymer alloy or polymer blend containing said modified polyphenylene ether, into said mold cavity, said modified polyphenylene ether, or said polymer alloy or polymer blend containing said modified polyphenylene ether, being melted by heating at a temperature higher than 175° C., and then the injecting of a fluid at a pressure higher than the atmospheric pressure during, or after the injection of said modified polypherylene ether, or said polymer alloy or polymer blend containing said modified polyphenylene ether.

A method for manufacturing a resin molded article made of a polymer alloy or polymer blend containing a polycarbonic ester derived from an aromatic dihydroxy compound and polystyrenic resin, comprising;

• the preparation of a mold whose cavity is designed to set X direction, Y direction, and Z direction molding shrinkage ratios of said resin molded article to be the same value each into a range of between 4.5/1000 and 6.5/1000, the injecting of said polymer alloy or polymer blend containing said polycarbonic ester derived from said aromatic dihydroxy compound and polystyrenic resin, said polymer alloy or polymer, blend being melted by heating at a temperature higher than 175° C., and then the injecting of a fluid at a pressure higher than the atmospheric pressure during, or after the injection of said polymer alloy or polymer blend.

A method for manufacturing a resin molded article made of an acrylonitrile-butadiene-styrene copolymer, or a polymer alloy or polymer blend containing said acrylonitrile-butadiene-styrene copolymer, comprising;

• the preparation of a mold whose cavity is designed to set X direction, Y direction, and Z direction molding shrinkage ratios of said resin molded article to be the same value each into a range of between 5.5/1000 and 7.5/1000, and the injecting of said acrylonitrile-butadiene-styrene copolymer, or said polymer alloy or polymer blend containing said acrylonitrile-butadiene-styrene copolymer, into said mold cavity, said copolymer, or said polymer alloy or polymer blend, containing a blowing agent in an amount of less than 5% by weight, and being melted by heating at a temperature higher than 160° C.

A method for manufacturing a resin molded article made of a high impact polystyrene which is a polymer blend of a styrene graft butadiene copolymer and a styrenic polymer, or a polymer alloy or polymer blend containing said high impact polystyrene, comprising;

• the preparation of a mold whose cavity is designed to set X direction, Y direction, and Z direction molding shrinkage ratios of said resin molded article to be the same value each into a range of between 5.5/1000 and 7.3/1000, and the injecting of said high impact polystyrene, or said polymer alloy or polymer blend containing said high impact polystyrene, into said mold cavity, said high impact polystyrene, or said polymer alloy or polymer blend, containing a blowing agent in an amount of less than 5% by weight, and being melted by heating at a temperature higher than 160° C.

A method for manufacturing a resin molded article made of a modified polyphenylene ether, or a polymer alloy or polymer blend containing said polyphenylene ether, comprising;

• the preparation of a mold whose cavity is designed to set X direction, Y direction, and Z direction molding shrinkage ratios of said resin molded article to be the same value each into a range of between 5.5/1000 and 7.5/1000, and the injecting of said modified polyphenylene ether, or said polymer alloy or polymer blend containing said modified polyphenylene ether into said mold cavity, said modified polyphenylene ether, or said polymer alloy or polymer blend, containing a blowing agent in an amount of less than 5% by weight, and being melted by heating at a temperature higher than 175° C.