Method for extruding into cavities defined by a fixed plate and moving metal molds a foamable on non-foamable thermoplastic polymeric resin

Abstract

Abstract A method for molding synthetic thermoplastic polymeric organic resin which also may be foamable comprising successively placing under pressure the, molten resin which is extruded from a die of an extruder in cavities to be formed between the die and continuously moving plural metallic moulds, and preventing a leakage of the molten resin out of the cavity in rear of the die by means of one or more barriers which are movable simultaneously or independently with each other, said barrier being adapted to be, at its tip end, always in contact with an inner floor of the metallic mould or held leaving a slight space therefrom and being adjacent to the rear portion of a die orifice thereby to enable the flow line of resin to be substantially perpendicular in relation to the direction of movement of the metallic mould and thus to be short and an apparatus for performing said method. There is also disclosed an apparatus as mentioned above, wherein in front of the die is provided a pressing cooling roll or endless belt having a function of adjusting a cooling temperature thereby to effect the solidification of the molten resin while pressing and cooling, whereupon the molded product is withdrawn. Thereby, the thermoplastic materials can be continuously molded without leakage of materials to give a molded article having excellent properties, especially stress-free property.

Inventors

• 👤 Jun Taga

Bibliographic Details