Molded plastic article and method of making the same
OwnerDavid E. Lawsoninventor
Life of this patent
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Abstract
A composite molded article composed of a backing layer of fiber-reinforced thermosetting resin and an outer layer of a thermoplastic resin which is mechanically interlocked to the backing layer through the fiber reinforcement. In fabrication, a layer of fibrous material impregnated with an uncured thermosetting resin is placed in a mold and a molten thermoplastic resin is injected into the mold. The heat of the thermoplastic resin serves to cure the thermosetting resin and the resulting composite article has a rigid, high strength backing formed of the reinforced thermosetting resin and has a smooth thermoplastic outer surface which is receptive to surface finishes.
Claims11
A method of making a molded composite structure, comprising the steps of placing in a mold cavity a fibrous material impregnated with an uncured thermosetting resin system capable of being cured by the application of heat, and injecting a molten thermoplastic resin into the mold cavity under pressure and at a temperature above the temperature required to cure the thermosetting resin system, the sensible heat of the thermoplastic resin providing heat required to cause the thermosetting resin system to cure to provide a composite structure having a cured thermosetting resin backing layer and a smooth thermoplastic resin outer surface bonded to the backing layer.
A method of making a composite structure, comprising the steps of placing in a mold cavity a mass of fibrous material impregnated with an uncured polyester resin system capable of being fully cured by the application of heat, said mass being spaced from a wall of said cavity to produce a space, injecting a heated molten thermoplastic resin into the space in the mold cavity and into contact with said mass, maintaining the temperature of the molten thermoplastic resin at a value below the volatilizing temperature of the components of the resin system, the heated thermoplastic resin being the sole source of heat to effect curing of the polyester resin system and provide a composite structure having a rigid polyester resin backing member and a smooth thermoplastic outer layer, and removing the composite structure from the mold cavity.
Dependencies are inferred from the claim text.