Abstract: Novel carbon fiber in the form of a plurality of tows or bundles comprising a multitude of continuous filaments is disclosed. The novelty of the carbon fiber resides in its unique combination of mechanical properties that make it admirably suited for use in composites comprising an organic matrix. Such composites are particularly useful in aerospace applications that have designs in which weight and performance are critical.

Abstract: High modulus, pitch-based, continuous carbon fiber having a density above about 2.18 g/cc and an electrical resistivity below about 1.6 micro-ohm-meter, and a method for making.

Abstract: Pitch-based carbon fibers on which silicone based spin finish oils remain in the amount of 0.1-2.0% by weight of said fibers and having a stack height of the crystallites L.sub.C (002) of 16-28.ANG., an interlayer spacing distance d.sub.002 of 3.46-3.49.ANG., a tensile strength of 5-50 Kgf/mm.sup.2 and an elongation of 0.3-8.0% are provided. The said pitch-based carbon fibers show good cohesiveness and lubricity of fiber bundles and superior in adaptation to various kinds of processes.

Abstract: PAN-based precursors are stabilized prior to carbonization in separate non-oxidizing and oxidizing environments according to process of the invention. Advantages of process include safer, more rapid stabilization and increase in the types of polymers which may be effectively stabilized.

Abstract: A method for producing high density, high strength carbon-carbon composite material, is provided by using pitch-based carbonaceous fibers carbonized at a temperature lower than 2200.degree. C. or structures, including said carbonaceous fibers as a principal constituent, as a reinforcement material, impregnating said reinforcement material with a carbonaceous material such as pitch or the like and then heat treating said impregnated material.

Abstract: Producing carbon fiber precursors and carbonized fibers comprise by treating a thin film of catalytic pitch at elevated temperature conditions, treating the resulting heavy isotropic pitch by agitating with an inert gas under elevated temperature conditions to form a mesophase pitch, forming green fibers from said mesophase pitch, stabilizing and optionally carbonizing said green fibers to obtain the desired product.

Abstract: A method of forming a sheet of material into a flower pot or flower pot cover comprising means for engaging portions of the sheet of material and forming pleats in predetermined portions of the sheet of material having a predetermined shape whereby the formed flower pot or flower pot cover has pleats in predetermined portions and of predetermined shapes.

Abstract: A noncircular cross-section carbon fiber wherein the cross-section is a noncircular one having at least one plane of symmetry passing the centroid and having an angle of rotational symmetry, .theta., defined by .theta.=360.degree./n, in which n is an integer of 1 to 10; wherein the internal structure has no lamellar structure and the fiber has a substantially uniform crystalline structure; and wherein the fiber surface has a surface smoothness S of 1.16 or below and the tensile strength and the tensile modulus of the fiber in the form of a resin-impregnated strand is 300 kg/mm.sup.2 or above and 20 ton/mm.sup.2 or above, respectively; a process for producing such carbon fiber; and a composite of such carbon fiber with a resin.

Abstract: Disclosed is a process for producing carbon materials which comprises the steps of preparing a raw material composition by mixing a methylene type linkage-containing condensation product of an aromatic sulfonic acid or a salt thereof with a solvent, the condensation product having been formed by means of a linkage of the formula--(CH.sub.2).sub.n --T.sub.x --(CHR).sub.m -- (1)where T is a benzene or naphthalene ring, R is a hydrogen atom, an alkyl group of 1 to 4 carbon atoms, or a benzene ring, and each of n, m and x is 0 or 1, but n and m should not be zero at the same time; spinning or molding the raw material composition; and carbonizing the spun fiber or molded article. Preferably, the aforesaid linkage is --CH.sub.2 --.

Abstract: A method for producing pitch-type carbon fiber, comprising the steps of discharging, from a spinning nozzle, a spinning pitch comprising an optically isotropic pitch and/or optically anisotropic pitch, maintained at such a temperature that the spinning pitch can have a viscosity of 20 poises or less, to form pitch fiber, while jetting a gas preheated to a temperature of 100.degree. C. lower than the temperature at which the spinning pitch can have a viscosity of 20 poises or less, or higher from the periphery of the spinning nozzle in the same direction as the discharging direction of the spinning pitch and parallel to the discharged pitch fiber to give extremely fine fiber having an average diameter of 5 .mu.m or less, and subjecting the thus spun fine fiber to infusibilization and carbonization.

Abstract: Use of a ribbon shaped flow configuration at the entrance to a round spinneret used for spinning carbon fibers from mesophase pitch promotes the formation of random microstructure and prevents formation of axial cracking in the fibers.

Abstract: A process is provided for preparing fibrous or film type activated carbon including the steps of carbonizing a cellulosic material and activating the resulting carbon, each stop occurring at a temperature between 200.degree. C. and 1100.degree. C. in an oxidation-suppressing atmosphere, in which, prior to activation, the cellulosic material or carbon is impregnated with at least one boron-containing compound and at least one phosphorus-containing compound. This impregnation treatment greatly increases the activation rate, so reducing the activation time and therefore energy costs. Higher levels of production of fibrous activated carbons can thus be achieved.

Abstract: The present invention relates to a method of manufacturing low-edge V-belts including the steps of: forming an unvulcanized belt annular body inside out by winding respective components constituting the elongated portion, tension-resistant portion, and compressed portion of the belt in laminated form on the circumferential surface of a forming drum; vulcanizing the unvulcanized belt annular body to obtain a vulcanized annular body; revolving the vulcanized annular body by winding on a pair consisting of a drive drum and an idle drum thereby to grind V-shaped grooves on the surface of the vulcanized annular body with a grinding wheel which is a group of grindstones whose cross-section is V-shaped being in pressure contact with the drive or idle drum; causing projections arranged on a positioning member which is capable of gradually increasing the depth of engagement to engage with the V-shaped grooves; and cutting the vulcanized annular body thus processed thereafter.

Abstract: This invention relates to an injection moulding process for the manufacture of multi-layered articles, especially articles having barrier properties. The process includes clamping a thermoplastic film over the cavity of a mould of an injection moulding process, the film being capable of being stretched. The film is then stretched within the mould by inserting the core of the mould, preferably using a core in which a central part enters the mould and partially stretches the film prior to the remainder of the core entering the mould. The mould is then closed, excess film is trimmed off and polymer is injected into the mould cavity. The resultant article is a multi-layered injection moulded article which, depending on the characteristics of the film and injected polymer, may have barrier properties to oxygen, liquids or the like that are superior to articles moulded from only the polymer. The process is particularly useful in the moulding of containers having a depth:width ratio of at least 0.5.

Abstract: Novel ceramic filamentary micro-tubular materials are described. An entirely fluid-phase method has been devised for producing such interwoven ceramic filamentary tubular materials. The process depends for its success the ability to generate a three-dimensional random weave of ceramic tubes, with diameters in the range of about 0.01 to 2.0 microns, by forming carbon filaments by catalytic decomposition of a hydrocarbon feed, coating the filaments with a ceramic coating and then oxidizing the coated filaments to remove the carbon core leaving behind hollow ceramic micro-tubular filaments. The ceramic micro-tubular materials may be free-standing porous structures and may have a variety of uses as thermal insulators, catalyst supports, superconductor supports, filters or as reinforcements for composites.

Abstract: There is provided a non-flammable expanded fiber comprising carbonaceous polymeric substantially irreversibly heat set fiber having an LOI value of greater than 40, and the fibrous structures thereof. Also, provided are stabilized expanded polymeric fibers.

Abstract: The present invention relates to a carbon fiber bundle comprising a regular coil-shaped fiber bundle and having excellent stretch characteristic. A process for producing a coil-shaped carbon fiber bundle according to the present invention comprises the steps of compositing at least two kind of pitches to spin them as single fibers, bundling the thus spun single fibers to form a fiber bundle, then infusibilizing the resulting fiber bundle under tension and carbonizing the fiber bundle.

Abstract: A method of manufacturing a dome- or cone-like acoustic diaphragm by a process including the step of heating a polymeric film comprising an aromatic polyimide, a polyoxadiazole or an aromatic polyamide, to a temperature range of 2,000.degree. C. or above, and the step of pressure molding. The heating and the pressure molding may be carried out at the same time when the polymeric film is heated for its graphitization. Alternatively, the pressure molding may be carried out while the polymeric film having been graphitized by the heating is further heated. Still alternatively, a polymeric film having been pressure-molded in the course of heat polycondensation of a polyamic acid may be graphitized by heating.

Abstract: A process for preparing carbon fibrils using discrete, unfused, metal-containing catalytic particles encapsulated in non-graphitic carbon, a carbide, or an organic polymer.

Abstract: Small diameter high strength carbon fibers are produced in a process in which the spinneret has a small diameter, the spinneret capillary temperature is at least 10.degree. C. higher than the predicted spin temperature of the pitch and the pitch flows through a high aspect ratio opening upstream of the spinneret.

Abstract: High thermal conductivity mesophase pitch based carbon fibers are made using a spinneret which has a sharply angled tapered region at the inlet to the spinneret capillary.

Abstract: A process for the preparation of substantially polycrystalline silicon carbide fibers are provided. The fibers may be fabricated to have a small diameter and are thermally stable at high temperature. The process is carried out by initially forming fibers from a preceramic polymeric precursor comprising phenyl-containing polyorganosiloxane resins. The fibers are then infusibilized to render them nonmelting followed by a pyrolysis step in which the fibers are heated to a temperature in excess of 1600.degree. C. in a nonoxidizing atmosphere to form substantially polycrystalline silicon carbide fibers. The substantially polycrystalline silicon carbide fibers which are formed have at least 75% crystallinity and have a density of at least about 2.9 gm/cm.sup.3. The polymeric precursor or the fibers contain, or have incorporated therein, at least about 0.2 % by weight boron.

Abstract: A method for producing graphite fiber comprising graphitizing carbon fiber having a strength of 500 kgf/mm.sup.2 or more and a modulus of elasticity of from 27,000 to 33,000 kgf/mm.sup.2, and having at least on the surface of the fibers, from 0.2 to 2% by weight of an epoxy resin as a sizing agent, from 0.005 to 0.10% by weight of silicon and 0.005 to 0.02% by weight of phosphorus based on the weight of carbon fiber having said epoxy resin, silicon and phosphorus.

Abstract: The invention relates to carbon fibrils characterized by a substantially constant diameter, length greater than about 5 times the diameter, an ordered outer region of catalytically grown, multiple, substantially continuous layers of ordered carbon atoms having an outside diameter between about 3.5 and 70 nanometers, and a distinct inner core region. Each of the layers and the core are disposed substantially concentrically about the cylindrical axis of the fibril. The fibrils are substantially free of pyrolytically deposited thermal carbon with the diameter of the fibrils being equal to the outside diameter of the ordered outer region.

Abstract: A catheter is provided which deters the backflow of blood between the insertion needle and the catheter cannula by forming the distal end of the catheter hub so as to restrict the inner diameter of the catheter cannula to a wiping fit with the engaged insertion needle. In a first embodiment the distal end of the catheter hub is pre-formed to its desired final inner dimension. The distal end of the hub is stretched to an oversize condition, the catheter cannula is attached to the hub, and the distal end of the catheter hub is heated, causing a stress relief of the previously stretched hub. The distal end of the catheter hub returns to its pre-formed dimension which will mechanically restrict the diameter of the catheter cannula at that point to form the wiping fit with the engaged needle.

Abstract: Hollow carbon fibers and carbon fibers having a generally C-shaped transverse cross-sectional area are produced by extruding a carbonaceous anisotropic liquid precursor through a spinneret having a capillary with a generally C-shaped cross-sectional area, into a fiber filament, controlling the viscosity of the molten precursor, the pressure of the molten precursor and the linear take-up speed of the filament to yield a fiber filament having a cross-sectional area shaped substantially like the shape of the cross-sectional area of the capillary and further having a line-origin microstructure, rendering the filament infusible, heating the filament in an inert pre-carbonizing environment at a temperature in the range of 600.degree. C. to 1000.degree. C. for 1 to 5 minutes, and heating the filament in an inert carbonizing environment at a temperature in the range of 1550.degree. C. to 1600.degree. C. for 5 to 10 minutes, to substantially increase the tensile strength of the filament.

Abstract: Carbon fibers having a multi-lobal transverse cross-section are produced by extruding a carbonaceous anisotropic liquid precursor through a spinneret having a capillary with a multi-lobal cross-section, solidifying the extruded filament, rendering the filament infusible, and heating the filament in an inert environment at a temperature sufficient to substantially increase the tensile strength and modulus of elasticity of the filament.

Abstract: Hollow carbon fibers and carbon fibers having a generally C-shaped transverse cross-sectional area are produced by extruding a carbonaceous anisotropic liquid precursor through a spinneret having a capillary with a generally C-shaped cross-sectional area, into a fiber filament, controlling the viscosity of the molten precursor, the pressure of the molten precursor and the linear take-up speed of the filament to yield a fiber filament having a cross-sectional area shaped substantially like the shape of the cross-sectional area of the capillary and further having a line-origin microstructure, rendering the filament infusible, heating the filament in an inert pre-carbonizing environment at a temperature in the range of 600.degree. C. to 1000.degree. C. for 1 to 5 minutes, and heating the filament in an inert carbonizing environment at a temperature in the range of 1550.degree. C. to 1600.degree. C. for 5 to 10 minutes, to substantially increase the tensile strength of the filament.

Abstract: A method for temperature conditioning a blank of plastic material in which a conditioning mandrel is placed within the blank and thereafter expanded into reliable abutment against the inner surface of the blank. The mandrel is thereafter returned to its initial position. The outer surface of the mandrel is adjusted to and maintained at a certain temperature, whereby, during the abutment, an energy exchange takes place between the blank and the mandrel for adjusting the temperature of the blank. At high temperatures of the mandrel, the mandrel is displaced out of the blank after such short time that the plastic material in the region of the abutment surface never passes the critical temperature of tackiness of the plastic material and/or thermal crystallization of the plastic material. As a rule, the expansion and contraction of the mandrel is repeated one or more times.

Abstract: A process is provided for the preparation of a pitch-based carbon fiber having a microstructure consisting of strip-like structural units extended in the longitudinal direction of the fiber, wherein the fractal dimension D of the arrangement of the strip-like structural units in the cross-section of the fiber has a fractal structure satisfying the requirement of the following formula (2) relatively to the observation scale r satisfying the requirement of the following formula (1) with respect to the cross-section of the fiber:E/2.5>r>E/25 (1)2.0>D>1.05 (2)wherein E in the formula (1) stands for a smallest principal radius of gyration of cross-sectional area of the cross-section of the fiber.

Abstract: An over-the-needle catheter assembly in which a restriction of the inner diameter of the catheter tube is formed in the proximity of the needle hub. The restriction is formed by heating a portion of the catheter tube to the softening point of the catheter material, stretching the catheter tube to cause the heated portion of the catheter tube to tighten about an inner needle or mandrel, then releasing the stretching force to allow the stretched portion to relax, leaving a small gap between the inner wall of the catheter tube and the outer diameter of the insertion needle. The small gap is preferably sized to be on the order of the size of the diameter of blood cells to restrict the flow of liquids past the restriction and into the catheter hub.

Abstract: In the manufacture of a decorative sheet material to be bonded to a substrate to provide a surface having a brushed metal appearance, a light-reflective, glossy metal layer is formed on a thermoformable carrier film. A pattern of straight and parallel microscopic cracks is created in the metal layer at a temperature below Tg of the carrier film by bi-directionally bending and drawing the resulting sheet material around a straight cracking member. Thereafter, the sheet material is stretched at a temperature above Tg of the carrier film. This creates an attractive brushed metal appearance of reduced gloss.

Abstract: For forming a resin-impregnated, fiber reinforced composite material sheet having laminated meshes of fibers into a U-shaped cross section, the sheet is placed onto a stationary forming die and an auxiliary forming die with the fibers of the sheet forming angles of approximately 45.degree. relative to opposite edges of an upper reference forming surface of the stationary die. Then, the sheet is pressed from above by a pneumatically expandable, elastic depressing die, whereby the auxiliary forming die is lowered against a resilient force relative to the stationary forming die. As the sheet is pressed further downwardly by the depressing die, the parts of the sheet which are to form flanges of the product are firmly held between the depressing die and the auxiliary forming die and bent downwards while the parts are subjected to extending forces in directions to prevent creases and lines from being formed by means of auxiliary forming ridges on the auxiliary forming die.

Abstract: A carbon/carbon composites is produced by impregnating a tow of carbon filaments with a carbonaceous pitch, placing the impregnated tow in an open container, then subjecting it to a heat treatment under hot isostatic pressing.

Abstract: A high strength, high modulus pitch-based carbon fiber has a crystalline structure in which the presence of the (112) cross-lattice line and the resolution of the diffraction band into the (100) and (101) diffraction lines, which indicate the three-dimensional order of the crystallite of the fiber, are not recognized, and in which the orientation angle (.phi.) of X-ray structural parameter is not greater than 12.degree. and the stack height (Lc) ranges between 80 and 180 .ANG.. The carbon fiber also has a single-fiber diameter of 5 to 12 .mu.m, tensile strength not lower than 3.0 GPa, tensile elastic modulus not smaller than 500 GPa and elongation not smaller than 0.5%.

Abstract: Polyacrylonitrile (PAN)-based carbon fiber in the form of a filament bundle has a high Modulus and a high Tensile Strength in the Impregnated Strand Test respectively between about 42 million and 50 million psi and between about 600,000 and 900,000 psi, and Short Beam Shear Strength between about 15,000 and 19,000 psi in the Laminate Test; this PAN-based carbon fiber also has an electrolytically treated surface at 0.2 to 0.8 columbs per inch per approximate 12,000 filaments. The preparation of this PAN-based carbon fiber was accomplished by stretching during carbonization previously stretched and stabilized fine denier precursor while maintaining temperatures and heat up rates within certain ranges.

Abstract: Novel ceramic filamentary micro-tubular materials are described. An entirely, fluid-phase method has been devised for producing such interwoven ceramic filamentary tubular materials. The process depends for its success the ability to generate a three-dimensional random weave of ceramic tubes, with diameters in the range of about 0.01 to 2.0 microns, by forming carbon filaments by catalytic decomposition of a hydrocarbon feed, coating the filaments with a ceramic coating and then oxidizing the coated filaments to remove the carbon core leaving behind hollow ceramic micro-tubular filaments. The ceramic micro-tubular materials may be free-standing porous structures and may have a variety of uses as thermal insulators, catalyst supports, superconductor supports, filters or as reinforcements for composites.

Abstract: Disclosed herein is a heat-resistant film obtained by biaxially-stretching a composition which comprises (A) 50-90 parts by weight of a polyetheretherketone having predominant recurring units of the formula: ##STR1## and (B) 50-10 parts by weight of a substantially linear poly(arylene sulfide) having melt viscosity of at least 1,000 poises. A production process of such a heat-resistant film is also disclosed, which comprises biaxially stretching the above composition in a temperature range at least equal to the crystallization temperature (Tc) of the poly(arylene sulfide) but not higher than the crystallization temperature (Tc) of the polyetheretherketone.

Abstract: A carbon based porous hollow fiber membrane excellent in heat resistance wherein it has pores which continuously penetrate from inner wall surface to outer wall surface of the membrane, maximum value of pore radius obtained from pore volume differential curve is in 10-1000 nm, total pore volume is 0.1-1 cm.sup.3 /g, curvature radius at flexing is 10 cm or less, and temperature at which 10% by weight of the membrane is decomposed and which is measured by TGA is at least about 300.degree. C. and a method for producing the abovementioned carbon based porous hollow fiber membrane having excellent heat resistance, characterized by comprising mixing an acrylonitrile based polymer (A) containing 90-100 mol % of acrylonitrile unit, a heat decomposable polymer (B) which is heat decomposed at a temperature of 600.degree. C.

Abstract: The deep-drawing of plastic foils for producing receptacles uses a drawing punch intermittently movable into a drawing mold and several expansion elements (jaws) radially movable on the drawing punch. The movement of the jaws and the punch is mutually effected to discontinuously move the drawing punch during its inward movement and to stop it for a respective predetermined dwell time. This can be combined with a continuous or discontinuous movement of the expansion jaw elements.

Abstract: A heat exchanger, especially a heat exchanger in the form of a comfort heat exchanger, includes two manifold elements adapted to receive and discharge fluid, and a plurality of tube units transversely located between the manifolds, each tube unit being integrally connected to substantially rigid end elements that fit into the manifolds. The tubes are preferably oriented and expanded to about their original diameter. The heat exchanger is intended to be fabricated from polymer, especially polyamide compositions. The tube units are intended to be manufactured using injection moulding techniques, and then subjected to orientation and expansion steps. Parts fabricated during manufacture of the heat exchangers are also included. The heat exchangers are particularly intended for use as comfort heat exchangers in automobiles.

Abstract: Carbon fiber precursors are stabilized regarding their mechanical properties by conducting the stabilization procedure in at least two steps, the first at a temperature at which the maximum plasticity of the polymer is attained while stretching the fiber 10-50% and the second at 200.degree.-300.degree. C., but higher than the first.

Abstract: An elastomer-coated fabric for use as a confinement. The confinement is formed by conforming a fabric to a mold having the shape of the desired confinement, and subsequently applying a layer of elastomer to the fabric. A curing operation then cures the elastomer such that the elastomer-coated fabric retains the shape of the mold. Advantageously, the curing operation also relaxes and heat sets the fabric in order to permit a controlled amount of further stretch, even if the fabric was stretched a maximum amount when it was conformed to the mold.

Abstract: This invention relates to the preparation of thermally stable, substantially polycrystalline silicon carbide ceramic fibers derived from a polycarbosilane resin. The unexpected thermal stability of these fibers is achieved by the incorporation of boron prior to ceramification.

Abstract: High shrinkage polyester fibers having good strength and uniform dyeability are disclosed, along with a method of producing the high shrinkage polyester fibers, by drawing a feeder yarn having a birefringence (n) of at least 0.0175 at a temperature below the glass transition temperature for the polyester and with carefully controlled draw ratios.

Abstract: An electrically conductive alumina fiber which heretofore known only as electrically insulative is now provided, which comprises an aluminum oxide matrix, and a continuous phase of carbon in the aluminum oxide matrix, the continuous phase of carbon affording an electrically conductive property to the fiber. Also, a method of producing the alumina fiber is disclosed, comprising pyrolyzing a fiber of poly[(acyloxy)aloxane] having a formula ##STR1## wherein, R.sub.1 represents CH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.3, R.sub.2 represents ##STR2## or other substituted aromatic group, in an inert atmosphere.

Abstract: Apparatus for shaping a tubular preform into a hollow body in which an axially directed wall of the preform primarily comprises oriented and/or crystallized plastic material. The tubular preform (10d) is fixed in a circumferential region (13d) in the vicinity of the mouth edge (14d) of the preform between mechanical forming devices (30,40), after which the devices, during continued clamping of the circumferential region, are displaced in the axial direction of the preform relative to a mandrel (50). Thus, the mandrel is displaced into the preform during simultaneous expansion thereof and the material is oriented and/or crystallized. In a preferred embodiment, there is compensation of the stretching forces, which arise in the material when inserting the mandrel, by applying a force to the bottom of the preform by a bottom support (75).

Abstract: Mesophase pitch centrifugally spun over a lip of the centrifugal rotor can be protected from coke and tar formation by conveying the molten pitch to the rotor's lip through channels within the rotor.

Abstract: Process of carbon fiber manufacture wherein the polyacrylonitrile precursor is stretched prior to oxidation step of the carbonization operation but after the stretching step of the spinning operation in limited temperature range. Process permits greater throughput in precursor manufacture and reduces flaws in the precursor because significant stretching is at lower line speeds typically used for oxidation and carbonization in making carbon fiber.

Abstract: A method of manufacturing controlled .Iadd.surface .Iaddend.electrical resistivity carbon fiber sheet products employing a carbonizable starting material, heating and drawing the starting material (if required), .Iadd.stabilizing and .Iaddend.oxidizing the starting material .Iadd.if required .Iaddend.at an elevated temperature of the order of 220 degrees Centigrade to effect molecular aromatic rearrangement of the starting material, .Iadd.partially .Iaddend.carbonizing the oxidized starting material at .[.an.]. elevated temperature .Iadd.values .Iaddend.in an oxygen free atmosphere within a furnace having an elevated temperature extending over a temperature range .Iadd.from about 370 degrees Centigrade .Iaddend. to about 1400 degrees Centigrade .[.by soaking the.]..Iadd.. The .Iaddend.starting material .Iadd.is soaked .Iaddend.at an elevated temperature for a predetermined period of time to provide a .Iadd.known .Iaddend.preselected .Iadd.surface .Iaddend.electrical resistivity to the .Iadd.partially .