초록 ▼

Spherical particles having a diameter between 0.007′ and 0.040′ are formed from melt extruded thermo-plastic material suitable for casting on a heated mold surface and melting thereon to form a thin layer of material having a nominal thickness of 0.040′ that is cooled and removed from the mold surfa

Spherical particles having a diameter between 0.007′ and 0.040′ are formed from melt extruded thermo-plastic material suitable for casting on a heated mold surface and melting thereon to form a thin layer of material having a nominal thickness of 0.040′ that is cooled and removed from the mold surface as a part having a porosity less than a visually observable threshold. The process includes the steps of providing microspheres formed of blended and melt extruded thermo-plastic, plasticizers and pigment additives that constitute less than 5% by weight of the blend and shaped as a smooth round spherical particle; providing a heated casting surface and distributing a predetermined charge of such microspheres against the heated casting surface; melting the microspheres as a layer of thermoplastic material having a porosity less than 0.003 inches and thereafter cooling and removing the non-porous layer from the casting surface.

대표청구항 ▼

1. A process for manufacturing plastic shells comprising the steps of providing a charge of thermoplastic microspheres melt blended with pigment, said microspheres having an outside diameter in the range of 0.007′ to 0.040′; providing a mold; placing said charge of microspheres into said mold; melt

1. A process for manufacturing plastic shells comprising the steps of providing a charge of thermoplastic microspheres melt blended with pigment, said microspheres having an outside diameter in the range of 0.007′ to 0.040′; providing a mold; placing said charge of microspheres into said mold; melt flowing the material into a shape corresponding to the mold surface and cooling the molded shape to remove said shape from the mold.