Abstract: Continuous ceramic (e.g., silicon carbide) nanofibers (502, 602, 604, 606, 608, 702, 704, 1102, 1104) which are optionally p or n type doped are manufactured by electrospinning a polymeric ceramic precursor to produce fine strands of polymeric ceramic precursor which are then pyrolized. The ceramic nanofibers may be used in a variety of applications not limited to reinforced composite materials (400), thermoelectric generators (600, 700) and high temperature particulate filters (1200).

Abstract: A process for producing polyacrylonitrile-base precursor fibers for production of carbon fibers, which comprises spinning a spinning dope containing 10 to 25 wt % of a polyacrylonitrile-base polymer having an intrinsic viscosity of 2.0 to 10.0 by extruding the spinning dope from a spinneret by a wet spinning or a dry wet spinning method, drying and heat-treating fibers obtained by the spinning, and then steam drawing the resulting fibers, wherein the linear extrusion rate of the polyacrylonitrile-base polymer from the spinneret is 2 to 15 m/min. Carbon fibers which are produced by stabilizing-carbonizing treatment of the polyacrylonitrile-base precursor fibers and which have a strand tensile modulus of 320 to 380 GPa and a conduction electron density of 3.0×1019 to 7.0×1019 spins/g as determined by electron spin resonance.

Abstract: A process for producing a friction material based on a sheet-like carbon fiber woven fabric for wet-friction elements, such as clutch linings or synchronizing ring linings. The woven fabric of carbon fibers is impregnated with a binder, in particular with a resin, to form a binder-impregnated fiber material. The prepreg is cured for a curing period under a curing temperature which is elevated with respect to the ambient temperature and is pressed mechanically on its surfaces with a pressing mold before the start and/or at least during part of the curing period.

Abstract: The various embodiments of the present invention provide improved carbon fibers and films, as well as methods of making the carbon fibers and films. The carbon fibers and films disclosed herein are generally formed from an acrylonitrile-containing polymer. The carbon fibers and/or films can also be formed from a composite that includes the acrylonitrile-containing polymer as well as carbon nanotubes, graphite sheets, or both. The fibers and films described herein can be tailored to exhibit one or more of high strength, high modulus, high electrical conductivity, high thermal conductivity, or optical transparency, depending on the desired application for the fibers or films.

Abstract: An object of the present invention is to provide carbon fibers which have a high conductivity, readily form a network in a matrix and are suitable for use in a radiating member as well as a molded product thereof. The present invention is pitch-based carbon fibers which are obtained from mesophase pitch and have an average fiber diameter (AD) of 5 to 20 ?m, a ratio (CVAD value) of the degree of filament diameter distribution to average fiber diameter (AD) of 5 to 15, a number average fiber length (NAL) of 25 to 500 ?m, a volume average fiber length (VAL) of 55 to 750 ?m and a value obtained by dividing the volume average fiber length (VAL) by the number average fiber length (NAL) of 1.02 to 1.50, and a manufacturing method and molded product thereof.

Abstract: A polyacrylonitrile-based polymer, containing a polymer of which main component is acrylonitrile, which satisfies at least one kind requirement selected from the following [a] to [d]. [a] Z-average molecular weight (Mz) determined by gel-permeation chromatograph is 800,000 to 6,000,000 and degree of polydispersity (Mz/Mw) (Mw denotes weight average molecular weight) is 3.0 to 10.0. [b] Z+1-average molecular weight (Mz+1) determined by GPC method is 3,000,000 to 10,000,000 and degree of polydispersity (Mz+1/Mw) is 6.0 to 25.0. [c] Mzm determined by gel-permeation chromatograph multi-angle laserlight scattering photometry is 400,000 to 1,000,000 and degree of polydispersity (Mzm/Mwm) is 3.0 to 10.0. [d] Z-average radius of gyration (Rz) determined by gel-permeation chromatograph multi-angle laserlight scattering photometry is 25 to 45 nm and its ratio to weight average radius of gyration (Rz/Rw) is 1.3 to 2.5.

Abstract: A metal carbide ceramic fiber having improved mechanical properties and characteristics and improved processes and chemical routes for manufacturing metal carbide ceramic fiber. Metal carbide ceramic fibers may be formed via reaction bonding of a metal-based material (e.g. boron) with the inherent carbon of a carrier medium. One embodiment includes a method of making a metal carbide ceramic fiber using VSSP to produce high yield boron carbide fiber. Embodiments of the improved method allow high volume production of high density boron carbide fiber. The chemical routes may include a direct production of boron carbide fiber from boron carbide powder (B4C) and precursor (e.g. rayon fiber) having a carbon component to form a B4C/rayon fiber that may be processed at high temperature to form boron carbide fiber, and that may be subsequently undergo a hot isostatic pressing to improve fiber purity. Another route may include a carbothermal method comprising combining boron powder (B) with a precursor (e.g.

Abstract: The present invention provides a thermosetting resin composite material excellent in mechanical strength and wear resistance at high temperature, which is achieved by converting graphite into thin-layered one and dispersing it in a thermosetting resin homogeneously. A thermosetting resin composite material, wherein an organically modified graphite having an organic compound molecule inserted between graphite layers is mixed with a thermosetting resin, the organically modified graphite being prepared by subjecting graphite to a chemical treatment to form a graphite interlayer compound having a low-molecular substance inserted between graphite layers and subsequently immersing the resultant product in a solution of an organically modifying agent, as well as a process for producing the same. Preferably, the organically modified graphite is mixed with a thermosetting resin to be converted into thin-layered one having a layer thickness of 0.

Abstract: Disclosed is a method for producing single- or multi-layered fiber performs by the TFP process with fiber strands which are aligned substantially such that they are oriented with the flux of force, are laid on at least one backing layer and are attached by at least one fixing thread. After completion of the TFT process, at least one fiber preform is introduced into a fixing device to secure the position of the fiber strands and the fixing threads and/or the backing layers are at least partially removed. As a result of the preferably complete removal of the fixing threads and/or the backing layer from the fiber preform, the latter has virtually ideal mechanical, quasi isotropic properties. In a preferred variant, the fixing threads and/or the backing layers are formed by a water-soluble material, so that they can be completely dissolved by water as the solvent and flushed out.

Abstract: A porous material comprising vapor grown carbon fiber in an amount of 10 to 90 mass %, fiber filaments of the carbon fiber forming a three-dimensional network and having a diameter of 1 to 1,000 nm, an aspect ratio of 5 to 15,000, a specific surface area (by BET method) of 2 to 2,000 m2/g, and the ratio of the intensity of the peak at 1,360 cm?1 in a Raman scattering spectrum of the carbon fiber to that of the peak at 1,580 cm?1 in the spectrum(I1360/I1580) is 0.1 to 2.0, wherein the porosity of the porous material (V/V0) is 0.50 to 0.99 and a specific surface area is 5 to 1,000 m2/g; and a production method and use thereof. The vapor grow carbon fiber impregnated in the porous material of the present invention does not contain aggregates and a three-dimensional network is formed between the fiber filaments, wherein length of each of the fiber filaments is maintained.

Abstract: A gas diffusion layer, including at least two functional areas (2a, 2b) which are operationally linked to one another, the first area (2a) having a porous structure and the second area (2b) being designed as a stabilization zone, achieves the object of providing a system which implements problem-free operation of a fuel cell while optimizing its efficiency. A system which includes two gas diffusion layers and a method for manufacturing the gas diffusion layer achieve the further cited objects.

Abstract: Method for manufacturing a carbonized carbon-carbon composite preform, by: mixing (a) chopped carbon fiber, chopped stabilized pitch fiber, or chopped oxidized polyacrylonitrile (PAN) fiber, (b) thermoplastic pitch binder powder, and (c) activated carbon powder to form a mixture of 15-60 parts by weight of chopped carbon fiber or chopped stabilized pitch fiber or chopped oxidized PAN, 28-83 parts by weight of thermoplastic pitch binder powder, and 1-12 parts by weight of activated carbon powder; depositing this mixture into a mold; pressing/heating the materials in the mold to form a preform by compaction; removing the compacted preform from the mold; and carbonizing the compacted preform. The preform is preferably configured in the form of an aircraft landing system brake disc.

Abstract: A nonwoven web product including ultra-fine fibers is formed utilizing a spunbond apparatus that forms multicomponent fibers by delivering first and second polymer components in a molten state from a spin pack to a spinneret, extruding multicomponent fibers including the first and second polymer components from the spinneret, attenuating the mulicomponent fibers in an aspirator, laying down the multicomponent fibers on an elongated forming surface disposed downstream from the aspirator to form a nonwoven web, and bonding portions of at least some of the fibers in the nonwoven web together to form a bonded, nonwoven web product. The multicomponent fibers can include separable segments such as islands-in-the-sea fibers, where certain separated segments become the ultra-fine fibers in the web product.

Abstract: Clutch linings comprising fiber-reinforced ceramic materials which contain short carbon fibers and whose matrix has a mass fraction of at least 40% of silicon carbide, process for producing them and their use in clutch systems, in particular for motor vehicles.

Abstract: Disclosed herein is a composite film comprising an organic polymer film; the organic polymer film having an elastic modulus of less than or equal to about 105 gigapascals when measured at room temperature; and a bundle of carbon fibers disposed in the organic polymer film; each bundle comprising a column and an end face; each bundle also having a longitudinal axis that is substantially parallel to the column and passes through the center of the column; the end face being fibrillated so as to have a surface area measured perpendicular to the longitudinal axis that is about 110 to about 250% greater than the surface area of a cross-section of the carbon fiber measured at the column.

Abstract: By using an oil agent for precursor fiber of carbon fiber containing a base compound and a liquid fine particle, and said liquid fine particle contains a liquid of which kinematic viscosity at 150° C. is 15000 cSt or more, it is possible to suppress an uneven stabilization in stabilizing process, and it becomes possible to provide a carbon fiber of high performance and uniform quality.

Abstract: The present invention relates to a method of producing carbon fiber reinforced ceramic matrix composites, the method of producing carbon fiber reinforced ceramic matrix composites according to the present invention is characterized in that the method comprises the steps of: producing a carbon fiber reinforced resin composite that is molded with a mixture in which carbon fibers and polymer precursors containing carbon are mixed; producing a carbon fiber reinforced carbon composite by depositing pyrolytic carbon during a rapid thermal gradient chemical vapor infiltration process while increasing the deposition speed in a direction from the inside to the outside by performing a thermal treatment on said carbon fiber reinforced resin composite at high temperature; and infiltrating liquid-phase silicon into the pores of said carbon fiber reinforced carbon composite.

Abstract: A composition comprising polymer-bound fiber tows containing carbon fibers, the polymer-bound fiber tows having an average length of 3 mm to 50 mm measured in the fiber direction, and an average bundle thickness of 0.1 mm to 10 mm measured perpendicular to the fiber direction, and in which at least 75% of all polymer-bound fiber tows have a length that is at least 90% and not greater than 110% of the average length combined with a carbon-ceramic material.

Abstract: A solid carbon has CNTs dispersed therein and is formed about three-dimensionally ordered spherical voids arranged in an opal-like lattice.

Abstract: The invention is directed to carbon fibers having high tensile strength and modulus of elasticity. The invention also provides a method and apparatus for making the carbon fibers. The method comprises advancing a precursor fiber through an oxidation oven wherein the fiber is subjected to controlled stretching in an oxidizing atmosphere in which tension loads are distributed amongst a plurality of passes through the oxidation oven, which permits higher cumulative stretches to be achieved. The method also includes subjecting the fiber to controlled stretching in two or more of the passes that is sufficient to cause the fiber to undergo one or more transitions in each of the two or more passes. The invention is also directed to an oxidation oven having a plurality of cooperating drive rolls in series that can be driven independently of each other so that the amount of stretch applied to the oven in each of the plurality of passes can be independently controlled.

Abstract: Apparatus and method for producing fibrous materials in which the apparatus includes an extrusion element configured to electrospin a substance from which the fibers are to be composed by an electric field extraction of the substance from a tip of the extrusion element, a collector disposed from the extrusion element and configured to collect the fibers, a chamber enclosing the collector and the extrusion element, and a control mechanism configured to control a gaseous environment in which the fibers are to be electrospun. The method includes providing a substance from which the fibers are to be composed to a tip of an extrusion element, applying an electric field to the extrusion element in a direction of the tip, controlling a gaseous environment about where the fibers are to be electrospun, and electrospinning the substance from the tip of the extrusion element by an electric field extraction of the substance from the tip into the controlled gaseous environment.

Abstract: A method and apparatus for the carbonization of polyacrylonitrile (PAN) precursor fibers. The apparatus comprises a furnace, or series of furnaces in side-by-side arrangement. Each furnace includes a heater, an air inlet and an air diffusion plate. The fiber is located in the furnace above the air diffuser plate, such that heated air is evenly dispersed over the fibers. The method generally comprises the steps of heat treating the PAN precursor in an oxidizing environment to stabilize the fiber, and then further heat treating the stabilized fiber in an oxidizing environment to carbonize the stabilized fiber. The method can be carried out in a single furnace, or can be carried out in a series of furnaces in a continuous process.

Abstract: A mixture of carbon-containing fibers, such as mesophase or isotropic pitch fibers, a suitable matrix material, such as a milled pitch is compressed while resistively heating the mixture to form a carbonized composite material. Preferably, the carbonized material has a density of at least about 1.30 g/cm3. Preferably, the composite material is formed in less than ten minutes. This is a significantly shorter time than for conventional processes, which typically take several days and achieve a lower density material. A treating component may be impregnated into the composite. Consequently, carbon/carbon composite materials having final densities of about 1.6–1.8 g/cm3 or higher are readily achieved with one or two infiltration cycles using a pitch or other carbonaceous material to fill voids in the composite and rebaking.

Abstract: Preform for carbon-carbon composite part (55) comprising multiple layers of fibrous mats (51, 52, 53) wherein each mat (51, 52, 53) comprises random carbon-containing fibrous matrix (11) having polymeric binder distributed therein and wherein adjacent mats (51, 52, 53) are bound together by additional polymer binder, stitching, and interlocking tabs. Also, method of manufacturing thick multi-layer composite preform, by: providing optionally reconfigurable tool including perforated screen through which vacuum can be drawn; delivering chopped fibers (b) to the tool while drawing vacuum therethrough to form fibrous object; delivering binder (c) to the fibrous object; melting or curing the binder (d) to make a fibrous mat (51, 52, 53); assembling plurality of the fibrous mats (51, 52, 53) and additional binder into the shape of a preform (e); and heat-pressing the resulting mat assembly (f) into finished thick preform (55).

Abstract: Carbon-silicon carbide brake preforms are manufactured by carbonizing a blend of carbon (e.g., polyacrylonitrile) fibers and thermosetting pitch resin, optionally along with a lubricant such as graphite,.to provide an intermediate product having open porosity and subsequently filling the pores of the intermediate product with silicon by a melt infiltration process. Molded articles that consist principally of carbon, that have relatively high strength and resistance to decomposition by frictional heat, and that are suitable for melt infiltration with silicon, are produced by, e.g.

Abstract: The present invention comprises a novel process for the preparation of carbon based structured materials with controlled topology, morphology and functionality. The nanostructured materials are prepared by controlled carbonization, or pyrolysis, of precursors comprising phase separated copolymers. The precursor materials are selected to phase separate and self organize in bulk, in solution, in the presence of phase selective solvents, at surfaces, interfaces or during fabrication, into articles, fibers or films exhibiting well-defined, self-organized morphology or precursors of well-defined, self-organized, bi- or tri-phasic morphology. Compositional control over the (co)polymers provides control over the structure of the phase separated precursor whose organization therein dictates the nanostructure of the material obtained after carbonization or pyrolysis, wherein each dimension of the formed structure can be predetermined.

Abstract: Process for producing shaped bodies comprising fiber-reinforced ceramic materials, where a green body is produced in a first step by introducing a press moulding composition into a mold, where the press moulding composition comprises carbon fibers and/or carbon filaments and pitch and/or resins which, when treated thermally and with the exclusion of oxidizing agents, form carbon-containing residues, the green body is cured in a second step by heating to a temperature of from 120° C. to 280° C. under pressure, the cured green body, also referred to as intermediate body, is carbonized in a third step by heating in a nonoxidizing atmosphere to a temperature of from about 750° C. to about 1100° C.

Abstract: Process for producing hollow bodies comprising fiber-reinforced ceramic materials, where mold cores whose shape corresponds to that of the hollow spaces are produced in a first step, at least one mold core together with a press moulding composition or formable fiber composition are introduced into a mold, where the press moulding composition comprises carbon fibers and/or carbon filaments and thermally curable carbonizable binders, in such a way that the position of the cores corresponds to the desired position of the hollow spaces to be formed in a second step, the composition is cured in a third step by heating to a temperature of from 120° C. to 280° C., to give a green body, the strengthened green body is carbonized and or graphitized in a fourth step by heating in a nonoxidizing atmosphere to a temperature of from about 750° C. to about 2400° C.

Abstract: A method for manufacturing carbon-carbon composites includes steps of producing a mat using carbon fiber, carbon fabric, carbon sheet, or staple fiber; laminating at least three layers of mats; producing a preform using the laminated mats with a needle punching method; performing a first thermal treatment process on the produced preform at a predetermined temperature; densifying the first-thermal-treated preform; performing a second thermal treatment process on the densified preform; forming a predetermined shape out of the second-thermal-treated preform; and performing an oxidation resistant treatment process of the shaped preform.

Abstract: The invention relates to a method for producing shaped bodies, especially threads or foils, from at least one polymer of the groups consisting of polysaccharide, polysaccharide derivative or polyvinyl alcohol by forming a solution of the polymer that contains an additive in a solvent containing amine-N-oxide, extruding the solution and precipitating the extrudate by contacting with a coagulant. The invention is characterized in that at least two polymeric solutions are formed. At least one of the two polymeric solutions contains one or more finely distributed additives and the at least two polymeric solutions are simultaneously extruded forming a combined extrudate.

Abstract: A mixture of carbon-containing fibers, such as mesophase or isotropic pitch fibers, a suitable matrix material, such as a milled pitch is compressed while resistively heating the mixture to form a carbonized composite material. Preferably, the carbonized material has a density of at least about 1.30 g/cm3. Preferably, the composite material is formed in less than ten minutes. This is a significantly shorter time than for conventional processes, which typically take several days and achieve a lower density material. A treating component may be impregnated into the composite. Consequently, carbon composite materials having final densities of about 1.6-1.8 g/cm3 or higher are readily achieved with one or two infiltration cycles using a pitch or other carbonaceous material to fill voids in the composite and rebaking.

Abstract: Connecting pieces for carbon material electrodes include carbon fibers. The fibers are oxidatively activated carbon fibers which additionally have a carbonized coating. The carbonized coating is a carbonization product of a coating material selected from wax, pitch, natural resins, thermoplastic and thermosetting polymers.

Abstract: A process for producing a fiber-reinforced, ceramic structural component comprising high-temperature resistant fibers which are reaction-bonded to a matrix of silicon carbide comprises the steps of coating bundles of fibers with pyrolysable binder and solidifying the binder, producing mixtures of fiber bundles, fillers and binders, pressing the mixtures to produce a pressed body, pyrolysing the pressed body under the exclusion of oxygen to form a porous, carbon-containing preform, infiltrating the preform with a silicon melt to form the silicon carbide matrix, in which various pressing compounds are produced, which contain fibers of different quality and in different proportions and different coatings. These pressing compounds are arranged at different levels and in different spatial directions in the press mould during the filling of the press mould. After the pressing, the regions produced in this way are retained in the press mould.

Abstract: The present invention relates to a process for the production of a braking band for a brake disk with venting passages and to a braking band which can be produced by the process. The process comprises the following steps: molding a core (200) of the braking band in a suitable mold (1), molding two covers (8) onto the core in a further suitable mold (101) so as to form a semi-finished product having a “sandwich” structure, firing the semi-finished product so as to produce a predetermined porosity of the covers, firing the semi-finished product further, in the presence of silicon, at a temperature such as substantially to bring about fusion of the silicon and its infiltration into the covers.

Abstract: A mixture of carbon-containing fibers, such as mesophase or isotropic pitch fibers, and a suitable matrix material, such as a milled pitch, is compressed while resistively heating the mixture to form a carbonized composite material having a density of about 1.5 g/cm3, or higher. The composite material is formed in under ten minutes. This is a significantly shorter time than for conventional processes, which typically take several days and achieve a lower density material. Consequently, carbon/carbon composite materials having final densities of about 1.6-1.8 g/cm3, or higher are readily achieved with one or two infiltration cycles using a pitch or other carbonaceous material to fill voids in the composite and rebaking.

Abstract: An apparatus for forming a non-woven mat of nanofibers by using a pressurized gas stream includes paralell, spaced apart, first, second, and third members, each having a supply end and an opposing exit end. The second member is located apart from and adjacent to the first member. The exit end of the second member extends beyond the exit end of the first member. The first and second members define a first supply slit. The third member is located apart from and adjacent to the first member on the opposite side of the first member from the second member. The first and third members define a first gas slit, and the exit ends of the first, second and third members define a gas jet space. A method for forming a non-woven mat of nanofibers utilizes this nozzle.

Abstract: A pitch precursor yam, which is stretch broken and formed into a fabric or felt which is heat treated into graphitic fiber media for fuel cell gas diffusion layer substrates and high thermal conductivity reinforced composites.

Abstract: A method for preparing a carbon fiber fabric impregnated with a thermoplastic plastic including providing a fabric which substantially consists of carbon fibers with a coating of an epoxy material without curing agent; bringing the fabric to a temperature in the range of 330° C. to 430° C.; and holding the fabric at the temperature for 120 to 240 minutes such that the carbon fibers remain unaffected and the epoxy material is aged or neutralized and loses its tacky character. Alternatively, the heat treatment may be carried out by bringing the fabric to a temperature of 450±70° C. for 15±5 minutes and subsequently to a temperature of 220±30° C. for 240±60 minutes. Fabrics prepared as described may be used in preparing laminates, which include a plurality of layers consisting alternately of the above-described fabric and a layer of thermoplastic plastic.

Abstract: Insulation materials suited to high temperature applications, such as the insulation of furnaces, are formed from a mixture of pitch carbon fibers, such as isotropic pitch carbon fibers, and a binder comprising a solution of sugar in water. The sugar solution is preferably at a concentration of from 20-60% sucrose to yield a low density material having high flexural strength and low thermal conductivity when carbonized to a temperature of about 1800° C.

Abstract: An annular body, and method of making same, comprising at least one wear surface portion, the portion comprising a plurality of layers held in a matrix, each layer consisting essentially of fibres which extend generally in one direction and parallel to each other and from the centre of the body to the periphery, whereby the wear of that surface portion is improved. The body can be formed into an aircraft brake disc.

Abstract: A separable tow of elongated polymeric filaments comprises a plurality of distinct sub-tows lightly and individually and separably joined, as by light crimping together along their edges or, if uncrimped, joined by presence of moisture, and capable of being packed into a container and later removed and separated. The filaments are preferably acrylic and have a total fineness of about 300,00-1,500,000 denier and the sub-tows each of which has a total fineness of about 50,000-250,000 denier, with a filament fineness of about 1-2 denier, and each sub-tow has a degree of entanglement of about 10-40 m−1 as measured by the hook drop test. The separable tow is made of a plurality of sub-tows, after separately drawing the sub-tows and subsequently removably joining the sub-tows into a single tow.

Abstract: A process for preparing fibers, including: (a) providing a spinning mixture including a dispersion of a flashing agent and an excess of a carbonaceous pitch; and (b) passing the spinning mixture from a high pressure region through an orifice to a low pressure region to form polyfilamentary pitch fibers. The pitch fibers may optionally be further treated to form polyfilamentary carbon fibers or graphite fibers, which may be incorporated into a resin to form a lightweight, conductive composite.

Abstract: A method for making high temperature filter media is provided by melt-spinning a plurality of fibers of preceramic thermoplastic polymer to form a nonwoven textile web of the fibers, curing and cross-linking the thermoplastic polymer to a thermoset polymer, and thermally decomposing the thermoset polymer to ceramic. Between the melt-spinning step and the curing step, the web is formed to a filter pre-form in a green state while still pliable and malleable. The filter pre-form is cured without re-melting the thermoplastic polymer and without destroying morphology.

Abstract: The present invention relates to carbon-matrix composites, such as carbon-carbon composites, and a method for forming them by forming a fabric of fusible and infusible fibers which can be processed and carbonized to form a composite. The methods disclosed herein permit preparation of composites which are particularly thin, uniform, and highly pure. The invention also relates to preprocessed fabrics and precarbonized composites, such as those comprising carbon or oxidized polyacrylonitrile fibers and fusible polyacrylonitrile fibers.

Abstract: Carbonaceous fibers having sharp ends and which are useful as an electron-emitting material, for example, in cold-cathode display devices. Carbonaceous fibers having a structure such that planes formed of carbon atoms in a condensed ring structure are concentrically grown around a fiber axis then subjected to heating at a temperature of 400-1200° C. in the presence of oxygen.

Abstract: This invention provides a pitch fiber bundle for carbon fibers of small size, a carbon fiber bundle, and a method for the production thereof, i.e. a method for the production of carbon fibers of a small size, a pitch fiber bundle, and a carbon fiber bundle at a lower cost with higher productivity than usual. The method for the production of pitch type carbon fibers according to this invention comprises dividing a plurality of pitch fibers into not less than two bundles, intertwining the bundles by exposure to currents of air thereby forming a first fiber bundle, binding a plurality of such first fiber bundles, and again intertwining the bound pitch fiber bundles by exposure to currents of air thereby forming a second fiber bundle.

Abstract: The present invention provides a method for manufacturing pitch-based carbon fiber by melt-spinning a mesophase pitch having optical anisotropy by using nozzles each equipped with an introduction hole entry portion, an introduction hole, an approach portion, and a discharge hole, and then applying thereto infusibilization, carbonization, or graphitization, wherein the mesophase pitch is passed through a plurality of contraction holes disposed in a substantially straight line in the introduction hole entry portion of each nozzle, then expanded in the introduction hole, and thereafter contracted in the approach portion and then spun by being passed through the discharge hole.

Abstract: A process and apparatus for the production of polyacrylontrile (PAN) polymer fibers from a polyacrylonitrile polymer, wherein a polyacrylonitrile polymer that comprises 90 weight percent or more polyacrylonitrile, optionally mixed with from about 30 to about 50 weight percent, based on the weight of the polymer, of a fugitive plasticizer, is heated, provided to an extruder in liquid form, extruded to form polyacrylonitrile fibers, and the fibers, immediately after the extrusion, are cooled, preferably in an air-cooled manifold, to a temperature of from about 110 to about 135° C.

Abstract: A method for making micrometer-sized carbon tubes is disclosed. A natural or synthetic fiber is first coated with a thermally stable coating material to form a coating layer over the fiber. Such coated fiber is then employed for making a hollow carbon tube, by removing the fiber and carbonizing the coating layer together with the residue of the fiber (if there is any). The removing treatment and carbonization treatment can be proceeded sequentially or concurrently.

Abstract: The carbon fiber precursor fiber bundle of the present invention is an acrylonitrile-based fiber bundle wherein the ratio of the length and width of the fiber cross section of a monofilament (length/width) is 1.05 to 1.6, and the amount of Si measured by ICP (Inductively Coupled Plasma) atomic emission spectrometry is in the range of 500 to 4,000 ppm. This type of carbon fiber precursor fiber bundle has a high compactness, and the carbonizing processing ability is good. Furthermore, for the carbon fiber bundle which is to obtained hereafter, the resin impregnating ability and tow spreading ability are good, the strength increases, and it has bulkiness. Furthermore, the carbon fiber precursor fiber bundle of the present invention is an acrylonitrile-based fiber bundle wherein the liquid content ratio HW is 40 wt. % or more and less than 60 wt. %.