Abstract: Granular material, gaseous fuel and air are preheated to just below the sintering temperature of the granular material. The hot granular material is passed through a mold in which a reticular device for distributing the fuel is provided to define a conical or vaulted surface with its vertex upstream, extending across the cross-section of the mold and defining the upstream end of a combustion zone into which the granular material passes after entering the mold. Air is supplied through a perforated wall and pushes the granular material as well as advancing with it to the combustion zone. Combustion of the fuel in the combustion zone thus defined brings the granular material to the sintering temperature and a fused rod of cellular structure (i.e. with small enclosed voids, generally not communicating with each other) is continuously formed that is pulled out by rolls in a pre-cooling section of the apparatus immediately downstream of the mold.

Abstract: This invention relates to a method for a manufacture of plastic sandwich element in which a first extruder is charged with essential ingredients for productions of foamed cellular plastic at a predetermined temperature. A second extruder is charged with essential ingredients for production of solid plastic at a temperature of at least 25 degrees Farenheit below the predetermined temperature. The resulting sandwich is extruded through an extrusion die forming an integral plastic sandwich with the heat of the foamed plastic layer causing a partial melting.

Abstract: An optical cable has a grooved central filament, the grooves following helical paths, the helices changing hand along the filament. In the manufacture of the filament, plastics is extruded past a fixed die and some way downstream, the filament is held and twisted first in one direction and then in the opposite direction so that the helical paths are introduced where the plastics exits the die. Dielectric optical waveguides are disposed in the grooves and the whole is surrounded by an extruded plastic sheath to produce an optical cable.

Abstract: This invention relates to a method of continuously extruding thermoplastic material with a solid, hollow or open cross-section, in which a liquid medium is continuously applied to the surface of the material being extruded before it leaves a nozzle which shapes the cross-section of the extruded material to the desired profile, and the surface of the material being extruded is also roughened, either before, simultaneously with or immediately after the application of the liquid medium, but before the material leaves the nozzle.

Abstract: Machines and process for making in a continuous operation a prestressed glass reinforced, thermally insulating panel, structurally stiff, and totally impervious, of indefinite length and with a cross-section shaped as an elongated parallelogram.Steps for manufacture include making the surface of the panel out of a tubular envelope of knitted or woven glass fabric, stretched over a special holding frame, to give it the desired parallelogram shape. Fastened by a continuous knitting process to the opposite faces of the glass fabric envelope, other glass fibers are stretched inside the envelope and arranged according to three principal directions, all of them oblique with respect to the panel faces. The glass fabric envelope is then coated with a plastic resin to make it impervious to gas and covered on one face at least with a metal liner. This liner, made of cryogenic alloy, has its edges upturned and folded, so as to be fastened to the glass reinforced plastic envelope.

Abstract: The walls which form a packing container are made from an extruded polystyrene foam plastic material which is stiffened along variously positioned rectilinear zones in the surface by effecting an increase in thickness of the plastic along those zones. The foamed plastic material is initially of uniform thickness during formation of the container but those zones of the walls which are to be thickened have a higher cell density factor than the remaining portions of the walls and hence a higher latent expansion capacity which, after the container has been formed, is released by heating to such an extent that the cell walls soften and are expanded by the increased gas pressure within them. The foamed plastic packing material is formed by extrusion through a die and is of uniform thickness. The desired zones of higher density are established in the material by subjecting those zones to a cooling operation.

Abstract: A method for producing a foamed plastic insulating coating in a wire. A gaseous foaming agent is mix with a resin and passed through a high pressure narrow passage and then through a lower pressure wide passage.The release of pressure, when the resin enters the wide passage, results in a foaming of the resin. The foamed resin is thereafter extruded through an orifice onto a wire. In one embodiment a chemical is added to serve as a nuclei for the gas bubbles formed during foaming. In a second embodiment, a second chemical is added to provide a smoother extruded surface. In still a further embodiment, the pressure in the wide passage is automatically controlled to remain at a predetermined preferred pressure.

Abstract: A method of producing porous tubes and hollow profile structures is characterized by coextruding different materials each through a separate section of a tube-forming extrusion die, one material being pore-forming and producing a porous wall section extending lengthwise of the extruded tube for providing a means of dispersing therethrough a fluid flowing internally of the tube, the other material being non-pore-forming or less pore-forming and producing a non-porous or less porous wall section extending lengthwise of the tube for providing mechanical strength to the tube.Also disclosed are a number of porous tube and hollow profile structures including various arrangements of porous and non-porous wall sections.

Abstract: A method and apparatus are provided for the extrusion of a thermoplastic material in modified form in which the thermoplastic material is introduced into the barrel of a screw extruder, and is heated and forced through the barrel: the material is passed through valve means which together with the temperature of the material is effective to produce a melt transition in the material at a predetermined point and to thoroughly mix the material; subsequently, the material is forced into a low pressure zone in the barrel where a modifying agent is introduced into the material; the resultant mass is forced out of the low pressure zone, and is passed through a mixing means effective to intensify the dispersion of the modifying agent in the mass, the mass is extruded and the extruded material collected.

Abstract: Continuous method and apparatus for treatment of a solid material submerged in a body of liquid wherein the material is sticky and/or has weak tensile strength. The material is supported, while it is so submerged, by a dynamic layer of the liquid lying between the material and a moving surface. The method is illustrated by heating and thereby foaming a strip of heat foamable thermoplastic resin while it is held submerged in a denser heat transfer liquid by a dynamic layer of that liquid generated by a moving belt above the foaming material. In an example, expandable high density polyethylene strip is foamed continuously while it is so held submerged in molten salt.

Abstract: Foam insulated conductor is produced by heating the conductor to a temperature at which the conductor retains sufficient heat to effect crosslinking and foaming of a polymer composition, followed by extruding the polymer composition onto the conductor, with the crosslinking and foaming being effcted by the retained heat.

Abstract: Disclosed is a method for continuous extrusion coating of a hollow core material with a highly expanded polyolefin resin, which is characterized by subjecting an extruded molten mass of an expandable polyolefin resin to external cooling at the point at which said molten mass begins to foam and supplying said hollow core material with the surface temperature thereof kept below the softening point of said polyolefin resin for thereby enhancing the fastness of adhesion of the highly expanded polyolefin foam with the hollow core material and at the same time facilitating the release of the two materials thus joined.

Abstract: Methods are provided for processing expandable thermoplastic materials with a typical compression relief design extruder screw having a helical flight for advancing and working a thermoplastic material. The screw is modified to shorten the feed and compression sections and to include a plurality of force-producing components in at least the compression section of the screw such that at least some portion of the components in any one turn of the flight lie in one plane essentially normal to the axis of rotation of the screw and such that the walls of the flight are uninterrupted. This arrangement controls the location of the rupturing or fragmenting of what is referred to as the solid bed and controls the manner in which it is fragmented to provide an extrudate at a die end of the extruder which has a constant temperature and which is uniform throughout each successive section of the thermoplastic material.

Abstract: Disclosed is a coaxial cable having greatly improved mechanical and electrical properties derived from a foamed dielectric having a dielectric constant in the range of 1.32 to 1.1, such cable being provided by a novel method of coating a center conductor of the cable with a dielectric with an extruded cellular polyolefin base composition which has been rendered cellular by the direct injection of a blowing agent in a liquid form into the polymer during an extrusion process. Also disclosed is an apparatus and a method of continuous wire electropolishing and pre-coating.

Abstract: This invention relates to a method for the manufacture of plastic sandwich element in which a first extruder is charged with essential ingredients for productions of foamed cellular plastic at a predetermined temperature. A second extruder is charged with essential ingredients for production of solid plastic at a temperature of at least 25 degrees farenheit from the predetermined temperature. The resulting sandwich is extruded through an extrusion die forming an integral plastic sandwich with the solid plastic layer controlling to a desired extent further foaming of the cellular plastic.

Abstract: A method of manufacturing a foamed polyolefin sheet which comprises the steps of laminating a film of noncross-linked thermoplastic resin free from a cross-linking agent to at least one surface of a cross-linked polyolefin base sheet containing a thermally decomposable foaming agent or a polyolefin base sheet containing the above-mentioned foaming agent and a cross-linking agent, and carrying out the thermal foaming of said film-fitted sheet while placing it on a supporting member under atmospheric pressure with the film-laminated surface of the polyolefin sheet being in contact with said supporting member.

Abstract: This invention relates to a method of continuously extruding thermoplastic material with a solid, hollow or open cross-section, in which a liquid medium is continuously applied to the surface of the material being extruded before it leaves a nozzle which shapes the cross-section of the extruded material to the desired profile, and the surface of the material being extruded is also roughened, either before, simultaneously with or immediately after the application of the liquid medium, but before the material leaves the nozzle.

Abstract: There is disclosed herein improved packages, and methods of forming same, of the type wherein a container, such as for example a glass container, like a bottle or jar, is provided externally thereof with a heat-shrunk, cellular thermoplastic member, circumferentially and snugly engaging a sidewall portion of the container; the improvement resides in employing, as the thermoplastic member, a composite structure, or laminate, of a closed cellular polymeric layer preponderantly of polystyrene having incorporated therein from zero weight percent up to compatible amounts of a copolymer of ethylene and an alkyl ester of alpha-beta monoethylenically unsaturated carboxylic acid or a copolymer of ethylene and vinyl acetate or a copolymer of ethylene and an alpha-beta monoethylenically unsaturated carboxylic acid, or mixtures thereof, and, in adhered relationship to said cellular layer, a layer of a noncellular polymeric material preponderantly of ethylene moieties having incorporated therein moieties of vinyl acetate,

Abstract: There is disclosed herein improved packages, and methods of forming same, of the type wherein a container, such as for example a glass container, like a bottle or jar, is provided externally thereof with a heat-shrunk, cellular thermoplastic member, circumferentially and snugly engaging a sidewall portion of the container; the improvement resides in employing, as the thermoplastic member, a composite structure, or laminate, having a closed cellular polymeric layer preponderantly of polystyrene having incorporated therein from zero weight percent up to compatible amounts of a copolymer of ethylene and an alkyl ester of alpha-beta monoethylenically unsaturated carboxylic acid or a copolymer of ethylene and vinyl acetate or a copolymer of ethylene and an alpha-beta monoethylenically unsaturated carboxylic acid, or mixtures thereof, and, in adhered relationship to said cellular layer, a layer of a non-cellular polymeric material preponderantly of ethylene moieties having incorporated therein moieties of vinyl ace

Abstract: A novel method and several different unique modifications of apparatus are disclosed for manufacturing a novel adhesive product. The product which results from use of the foam is a pair of substrates adhered together by compressed foam. The adhesive foam is created by intimately mixing air or any relatively inert gas with thermoplastic adhesive while the adhesive is in the liquid state and then pressurizing the liquid/gas mixture so as to force the gas into solution with the liquid adhesive. The liquid adhesive is subsequently dispensed at atmospheric pressure with the result that the gas is released from the solution and becomes entrapped in the adhesive to form a homogenous closed cellular adhesive foam.

Abstract: A process for the production of cross-linked polyethylene foam layers which have an anisotropic pore structure in at least one internal layer, wherein at least three polyethylene sheets which contain equal quantities of peroxide as cross-linking agent and differing quantities of a chemical blowing agent are arranged as a multilayer structure in such a way that the two external layers are formed by the sheets which contain a smaller proportion of blowing agent, and the structure is heated, preferably in a continuous heating furnace, so that the individual sheets are cross-linked and at the same time welded together to form a laminate which is subsequently foamed by increasing the temperature to between 190.degree. and 250.degree. C.

Abstract: A method and apparatus are provided for employment in thermoplastic foam extrusion utilizing a direct-injection extrusion process. Thermoplastic foam material is produced which is characterized by having relatively smooth external skin surfaces, and an internal cellular structure, by providing intensive cooling of the foam material immediately upon its issuance from an extrusion die orifice. Means are also provided for controlling the cooling rate utilizing an adjustable device which controls the rate of cooling air flow and air temperature within the extended foam tube.

Abstract: Expanded styrene polymer sheet material is produced by extruding expandable and/or general purpose styrene polymer with a conventional blowing agent, a nucleating system and small amounts of finely divided hydrophilic silicon dioxide and alkaline earth metal oxide. The resulting product has very fine, uniformly sized pores and improved flexibility.

Abstract: Expanded styrene polymer sheet material is produced by extruding expandable and/or general purpose styrene polymer with a conventional blowing agent, a nucleating system and a small amount of finely divided hydrophobic silicon dioxide. The resulting product has very fine, uniformly sized pores and improved flexibility.

Abstract: A method of making a non-slip plastic film comprises extruding separate plasticized plastic materials in two streams so that one stream abuts against and adheres to the other to form a combined plastic layer. The combined plastic layer is then stretched by directing air centrally into a tubular formation of this layer. One of the plastic materials comprises a material having an expanding agent or a foaming agent and the stretching causes the breaking of the voids of the foam plastic to form a rough, irregular net-like formation on the exterior of the other plastic. The apparatus includes two separate nozzles arranged to extrude plastic material so as to intersect and form a combined plastic.

Abstract: A foamed plastic material of polyethylene or polystyrene capable of being heat-shaped for use in making packing containers wherein by stretching of the foam the cells therein are given a lenticular or elongated structure. In the case of a lenticular cell structure, produced by a bi-axial stretching operation, the individual cells are situated in layers in parallel planes. In the case of an elongated cell structure, produced by a mono-axial stretching operation, the individual cells are situated with their longitudinal axes in parallel planes.

Abstract: There is disclosed herein improved packages, and methods of forming same, of the type wherein a container, such as for example a glass container, like a bottle or jar, is provided externally thereof with a heat shrunk, cellular thermoplastic member, circumferentially and snugly engaging a sidewall portion of the container; the improvement resides in employing as the thermoplastic member a composite structure, or laminate, of a closed cellular polymeric layer in which the polymer is a polymer of predominantly olefin moieties and, in adhered relationship to the closed cellular layer, a non-cellular polymeric layer n which the polymer is a polymer of predominantly olefin moieties with the cellular layer being in snug, heat shrunk engagement with the sidewall portion of the container and the non-cellular layer being disposed outwardly of the cellular layer.

Abstract: A method of producing a lightweight, strong, uniform, foamed layer containing tubular film with good opacity which can be heat-shrunk onto an annular substrate such as a glass bottle rapidly and uniformly is accomplished by co-extruding a low density polyethylene and a mixture of an ethylene polymer and a blowing agent under particular conditions and causing the blowing agent to decompose thereby foaming the ethylene polymer.

Abstract: Foam-encapsulated laser fusion targets are fabricated by suspending fusion fuel filled shells in a solution of cellulose acetate, extruding the suspension through a small orifice into a bath of ice water, soaking the thus formed shell containing cellulose acetate gel in the water to extract impurities, freezing the gel, and thereafter freeze-drying wherein water and solvents sublime and the gel structure solidifies into a low-density microcellular foam containing one or more encapsulated fuel-filled shells. The thus formed material is thereafter cut and mounted on a support to provide laser fusion targets containing a fuel-filled shell surrounded by foam having a thickness of 10 to 60 .mu.m, a cell size of less than 2 .mu.m, and density of 0.08 to 0.6.times.10.sup.3 kg/m.sup.3. Various configured foam-encapsulated targets capable of being made by the encapsulation method are illustrated.

Abstract: An improved process for preparing foamed articles of thermoplastic resin having a hard, mar-resistant surface that is flat and smooth and resembles natural wood, and an extrusion die therefor. In the process a softened thermoplastic is extruded through apertures of the extrusion die of the invention which is a fiered die having a resin discharge plate having a peripheral recessing portion and a protruding interior portion which are formed on the resin discharge plate by one or more step-ups. Each of the peripheral and interior portions of the resin discharge plate is provided with a plurality of apertures, the aperture density of the peripheral portion being greater than that of the interior portion. A longitudinally extending cooling frame is mounted adjacent the resin discharge plate and extends in the direction of extrusion to at least the forward face of the interior portion of the plate.

Abstract: This invention generally pertains to a process for producing a foamed thermoplastic resin article by utilizing the phenomenon that a solid thermoplastic resin sorbs a gas under pressure, and more particularly to a process for producing a foamed thermoplastic resin article comprising the steps of making a solid thermoplastic resin containing a nucleating agent quickly sorb a gas under a high pressure P.sub.1, lowering said gas pressure to a low pressure P.sub.2 (P.sub.1 > P.sub.2 > the atmospheric pressure) when the gas sorption quantity reaches a predetermined value so as to equilibrate or stabilize said predetermined gas sorption quantity, feeding said gas sorbed thermoplastic resin into an extruder while said gas pressure is maintained at said low pressure P.sub.2 and extruding the resultant resin to thereby produce a foamed thermoplastic resin article. In this invention, the gas sorbed by the thermoplastic resin contributes to foam in the thermoplastic resin.

Abstract: Pencils made with a resin-based sheath to replace wood sheaths. A sheath material consisting essentially of a resin binder, a fibrous filler and a metallic soap is extruded around a marking core. The resulting extrudate is immediately chilled after leaving the die, and cut into pencil lengths. The apparatus includes core feeding and transport means, core preheating means and chilling means. The resulting pencils possess the physical qualities associated with wood-sheathed pencils due to the fine, closed cell structure of the sheath material. The surface of the sheath is smooth and may be coated with a pigmented resin or painted.

Abstract: An apparatus for producing a foamed thermoplastic resin comprising an extruder including a barrel through which a thermoplastic resin is fed while being melted and a head to extrude said molten resin from said barrel, and gas injector means to inject a gas into said molten resin in said barrel through a gas injecting port in said barrel whereby said foamed thermoplastic resin article is formed by extruding said gas containing molten resin, said gas injector means characterized by comprising a gas metering means or gas flow rate setting means disposed adjacent and connected to said gas injecting port to conduct said gas therethrough while a constant flow rate is maintained, and a volume of a gas passage from said gas flow rate setting means to said gas injecting port in said barrel being sufficiently set for the gas pressure in said gas passage to respond to variation in the pressure of said molten resin in said barrel.

Abstract: A process is provided for the production of a cellular thermoplastic body, wherein solid thermoplastic material is melted under pressure in an extruder, a gaseous blowing agent is injected into the molten thermoplastic material under pressure and said molten thermoplastic material and gaseous blowing agent is passed to a zone of reduced pressure to effect the cellular expansion of said thermoplastic material by said gaseous blowing agent, and wherein said gaseous blowing agent is metered at sonic velocity at a point upstream of the injection of said gaseous blowing agent into said molten thermoplastic material.

Abstract: A product comprising a cellular plastic material is extruded from a modified conventional extrusion head by injecting a gaseous expanding medium into advancing fluent plastic material through porous material forming at least a portion of a section of the core tube in an extrusion chamber. By controlling the interrelationship between various process parameters such as the speed and pressure of the advancing fluent plastic material, the rate of injection of expanding medium into the advancing plastic material, the place where the expanding medium is injected, and the amount the extruded product is allowed to expand before cooling, it is possible to extrude, from a single source of fluent plastic material, a product comprising many different configurations of cellular and solid plastic material such as a uniform cellular structure throughout, or a cellular plastic inner section with a more dense outer covering.

Abstract: A coaxial cable having improved mechanical and electrical properties comprising an inner conductor; an outer inert gas blown cellular ethylene or propylene polymer dielectric layer having in unexpanded form a density of about 0.86 to 0.96 grams per cubic centimeter, a melt index of about 0.05 to 10 decigrams per minute and an expanded density up to 0.6 grams per cubic centimeter, said core member having a dissipation factor value of .ltoreq. 250 microradians at an electrical transmission frequency range of from 50 to 300 mega Hertz; and an outer coaxial conductor.

Abstract: An apparatus for extruding a tubular article from a cellular plastic compound comprising a bushing defining a passage extending therethrough, an internal mandrel within the passage of the bushing and cooperating therewith to define a die passage, and an external mandrel downstream of the internal mandrel. The die passage has a tapered section and an outlet section with the overall width of the tapered section reducing as it extends toward the outlet. The outlet section terminates in an outlet. The gap dimension of the tapered section is greater than the gap dimension of the outlet section. The die passage has a transition section which is of progressively reducing thickness to smoothly blend the tapered section and the outlet section.

Abstract: A container closure liner in the form of a layer arrangement having a compressible intermediate layer having high frequency heat sealing characteristics disposed adjacent the lip of a container for bonding thereto. Another layer may be squeezed beyond the periphery of the material for making a better seal.

Abstract: An apparatus for the production of extruded profiles of foamed thermoplasts consisting of an extruder having an extrusion screw or helix and a form-giving extruder head having a flow channel there-through, at least part of the length of said flow channel being divided by separating walls having a thickness of 0.2 to 3 mm arranged in the axial direction into individual channels of such a length and cross-section area whereby each individual channel has a nozzle coefficient k of from 0.1 to 2mm.sup.3, characterized in that thorn-like pins are inserted into some of the individual channels; as well as the process of extrusion.

Abstract: An apparatus for the production of extruded profiles of foamed thermoplasts consisting of an extruder having an extrusion screw and a form-giving extruder head having a flow channel therethrough characterized in that at least part of the length of said flow channel is divided by separating walls having a thickness of 0.2 to 3 mm arranged in the axial direction into individual channels of such a length and cross-section area whereby each individual channel has a nozzle coefficient k of from 0.1 to 2 mm.sup.3 ; as well as the process of extrusion.

Abstract: An automated system for fabricating a lead pencil in which the lead is securely bonded to a sheath formed of foam plastic material and having a smooth skin. In the system, individual pieces of lead which are pre-treated with a heat-activatable adhesive layer, are sequentially fed into an extrusion die in which the lead is ensheathed by molten foam plastic material whose heat serves to activate the adhesive. The string of ensheathed lead pieces emerging from the die are advanced through a sizing jig in a cooling station wherein the diameter of the sheath is rendered uniform and the surface thereof is formed into a smooth skin, the sheath being rigidified in the station and the activated adhesive being set to strongly bond the lead to the sheath. The resultant rod is fed to a cut-off station which serves to sever the rod into individual pencils.

Abstract: Generally linear foamable strandular particles which are asymmetrical about a plane generally containing the longitudinal axis provide a desired curled dunnage material when heated to cause foaming. A wide variety of methods may be used to introduce the desired asymmetry.