Abstract: A process for producing injection molded articles of foamed thermoplastic material via injecting of a molten mass of thermoplastic material containing a foaming agent into a mold cavity is improved so as to substantially reduce production time by the utilization of a step introducing a cold compressed gas into the mold cavity internally of the injected mass of material, while it is still at least internally molten. The article produced by the process is characterized by an outer skin of tightly structured material surrounding a body of microcellular foam material having an internal void or voids bounded by material of a tightly structured nature.