Abstract: A press for moulding plastic materials for the manufacture of gramophone disc records or like flat parts comprises a fixed press platen carrying a first mould element, a movable press platen guided along columns fast with the fixed platen and a movable intermediate platen carrying a second mould element. A mechanical device is provided to urge the movable press platen to the fixed press platen. A fluid pressure is supplied between coacting cylinder and piston provided respectively in the movable platens. The intermediate platen is supported and guided by the movable platen without any contact between this intermediate platen and the columns.

Abstract: A first thermoplastic resin for forming the shell of an article is charged into the front portion of an injection cylinder and a second thermoplastic resin for forming the core of the article is charged into the rear portion of the injection cylinder. Both resins are substantially separated, being in contact only a central area of the cross-sectional plane of the injection cylinder. These thermoplastic resins are injected in a mass into a mold cavity with the second resin enveloped by the first resin, and finally solidified in the mold cavity resulting in a molded article having sandwich construction. Various sandwich articles can be obtained easily by means of a single injection molding machine. The process also allows repeated injection operations without exposure of the core material on the surface of the molded article.

Abstract: Synthetic-resin bodies, preferably composed of hardenable synthetic resins and especially thermosetting resins are formed by introducing a foamable resin into a mold cavity, setting the foamable resin upon permitting the same to expand to fill the mold cavity, and thereafter introducing into the mold cavity, without changing the volume thereof, at least one additional synthetic resin while the foamed body is plastically deformable but possesses sufficient rupture strength to prevent penetration. The resulting body thus has a surface layer of the second material which displaces the foamed first material.

Abstract: A body to be packaged is suspended on filaments in an upwardly open porous mold which is lined with a gas-pervious sheet material. The mold is capped and a synthetic resin is introduced therein and expanded, the air in the mold being displaced out through the mold walls, to completely encapsulate the body. The supporting filaments, extending from the package so formed can be drawn across each other to cut an opening in the package permitting the packaged body to be removed. The sheet material covers the outside of the package, being integral therewith, and protects the package while permitting it to be written on.

Abstract: Apparatus is disclosed for molding foamed thermoplastic articles characterized by a cellular core and a substantially non-cellular integral peripheral shell comprising:A. extruder means adapted to flux a thermoplastic material;B. Disperser means connected to said extruder means for producing a dispersion of fluid blowing agent in the fluxed thermoplastic material comprising a cylindrical barrel having therein at least one ratatable disc dispersion unit with an alternating spaced series of perforated-solid rotating discs; said perforated disc, providing a high shear mixing zone, having outer edge surfaces in close rotating clearance with the inner walls of said barrel; the outer edge surface of said rotating disc being spaced from the inner walls of said barrel to form an intense shear mixing zone; and wherein said blowing agent is dispersed when passed through the apertures of said perforated disc and is intimately dispersed throughout the thermoplastic material when passed through said intense shear zone;C.

Abstract: Heat-expandable beads of thermo-plastic material such as polystyrene are moulded by steam heating in a metal mould and venting the interior of the mould through apertures in plugs set into ports in the wall of the mould. The plugs are made of low heat conductivity material, for example nylon, to prevent the apertures being blocked by fusion of the beads in contact with the plugs due to heat conduction from the wall of the mould. The steam may be introduced into the mould through apertures in nylon plugs set in ports in the wall of the mould, the low heat conductivity of the nylon preventing the steam raising the plugs to a temperature at which the beads would burn onto the plugs. The same plugs may be used to introduce steam into the mould and then vent the interior of the mould.

Abstract: Apparatus for producing a foamed fibre dispersion for deposition on the foraminous support of a machine for manufacturing non-woven fibrous material includes an outlet manifold closed except for an outlet from which foamed fibre dispersion issues for deposition on the foraminous support, as well as a plurality of input openings, an inlet manifold closed except for an inlet through which the apparatus is supplied with dispersion to be foamed, and a plurality of outlet openings. A plurality of closed foam-forming pipes each effect communication between an individual one of the inlet manifold outlets and an individual one of the outlet manifold inlet openings. Each foam-forming pipe includes at least one internal region defined by zones of alternately decreasing and increasing cross section so as to establish cross sectional restriction to increase the speed of flow of dispersion, thereby to create in the foam-forming pipe turbulence to effect foaming of the dispersion.