Method of supplying a moldable mixture of materials to an article forming mold of an injection molding machine

The method of supplying a moldable mixture of material to an article forming mold of an injection molding machine which machine has an elongated material feed screw selectively rotatable within an elongated chamber and which chamber has longitudinally contiguous inlet, intermediate and discharge zones and which machine has controllable heating means for independently heating material within such zones, respectively, the improvement comprising:

• mechanically mixing a granular thermoplastic resin with a granular filler to form a granular mixture,
• supplying said mixture to such an inlet zone,
• conveying said mixture sequentailly through such inlet, intermediate and discharge zones,
• heating said mixture within such a chamber by supplying heat to such inlet, intermediate and discharge zones to initially convert the resin contained in said mixture as supplied into a molten state and maintain said converted resin in a molten state throughout said chamber and to simultaneouslky heat the filler contained in said mixture with said filler remaining as a heated solid throughout said chamber,
• said heating of said zones being of a magnitude that the temperature of the molten resin and said heated solid filler in such intermediate zone is lower than the temperature of said molten resin and said heated solid filler in such inlet and discharge zones,
• and discharging said molten resin and said heated solid filler from said discharge zone to such an article forming mold.