Abstract: A method for producing carbon fibers in a vertical carbonizing furnace and an apparatus for producing carbon fibers using such a method are disclosed. The furnace includes a heating chamber for carbonizing fibers, the furnace including,(i) a fiber inlet at the upper end of the chamber(ii) an air tight sealed fiber outlet at the lower end of the furnace,(iii) an inert gas inlet provided on the wall of the chamber and above the fiber outlet,(iv) at least one inert gas injection portion, formed on the wall of the chamber, each capable of forming a curtain of inert gas across the heating chamber, each injection portion being provided between the gas inlet and the fiber inlet,(v) at least one outlet each being provided below each inert gas injection portion, and(vi) a heating member capable of controlling the temperature in the heating chamber in such a manner that the temperature gradually increases from the upper end toward a lower end of the heating chamber.

Abstract: Active carbon fibers derived from acrylic fibers and having a BET specific surface area (SA) of 800 to 2,000 m.sup.2 /g, a pore volume (Vp) to (SA) ratio, i.e., (Vp)/(SA), of from 5.times.10.sup.-4 to 14.5.times.10.sup.-4, and a methylene blue adsorption rate constant of not less than 5.times.10.sup.-1 sec.sup.-1, and a filter adsorption unit for water purification using said active carbon fibers; the unit is useful to remove compounds having a wide range of molecular weights from an aqueous liquid.

Abstract: A composite rope obtained by a process comprising(1) impregnating a fiber core of a reinforcing fiber bundle with a thermosetting resin,(2) coating the outer periphery of the resin-impregnated fiber core with fibers, and(3) curing the thermosetting resin with heat.

Abstract: A carbonaceous fiber having a carbon content of from 70 to 90%, a high tensile strength and a high modulus of elasticity, which is produced by a method which comprises preoxidizing an acrylic fiber in an oxidizing atmosphere at a temperature of from 10.degree. to 60.degree. C. below the decomposition point of said fiber, to prepare a preoxidized fiber having a degree of orientation of not less than 78% at an angle of X-ray diffraction (2.theta.) of 25.degree. and a specific gravity of from 1.30 to 1.40, pyrolyzing the preoxidized fiber in an inert gas atmosphere by passing the fiber firstly through a lower temperature zone having a temperature of not higher than 750.degree. C. and then through a higher temperature zone having a temperature of from 750.degree. to 950.degree. C., during the pyrolysis controlling the tension of the fiber so that the change of the fiber length during pyrolyzing is from +16% to -8.8% based on the length of the preoxidized fiber.

Abstract: Acrylic fibers suitable for producing preoxidized fibers free from coalescence which have a fluorine-containing surface active agent or further have at least one phosphoric surface active agent selected from the group consisting of compounds represented by the following formulae (I), (II) and (III): ##STR1## (wherein all the symbols are defined in the appended claims).

Abstract: Active carbon fibers derived from acrylic fibers and having a BET specific surface area (SA) of 800 to 2,000 m.sup.2 /g, a pore volume (Vp) to (SA) ratio, i.e., (Vp)/(SA), of from 5.times.10.sup.-4 to 14.5.times.10.sup.-4, and a methylene blue adsorption rate constant of not less than 5.times.10.sup.-1 sec.sup.-1, and a filter adsorption unit for water purification using said active carbon fibers; the unit is useful to remove compounds having a wide range of molecular weights from an aqueous liquid.

Abstract: A method for producing carbon fibers in a vertical carbonizing furnace and an apparatus for producing carbon fibers using such a method are disclosed. The furnace includes a heating chamber for carbonizing fibers, the furnace including,(i) a fiber inlet at the upper end of the chamber(ii) an air tight sealed fiber outlet at the lower end of the furnace,(iii) an inert gas inlet provided on the wall of the chamber and above the fiber outlet,(iv) at least one inert gas injection portion, formed on the wall of the chamber, each capable of forming a curtain of inert gas across the heating chamber, each injection portion being provided between the gas inlet and the fiber inlet,(v) at least one outlet each being provided below each inert gas injection portion, and(vi) a heating member capable of controlling the temperature in the heating chamber in such a manner that the temperature gradually increases from the upper end toward a lower end of the heating chamber.

Abstract: High-performance carbon fiber or graphite fiber can be produced by treating the preoxidized fiber or carbon fiber strand with an aqueous solution containing at least one member of polyethylene oxide having a molecular weight greater than 100,000, methyl cellulose, ethyl cellulose, and hydroxyethyl cellulose, and drying the treated fiber strand at a temperature lower than 250.degree. C. prior to carbonization or graphitization.

Abstract: An activated carbon fiber spun yarn having excellent workability and adsorptive property is disclosed. The activated carbon fiber spun yarn comprising activated carbon fibers having a specific surface area of 500 to 1,500 m.sup.2 /g, a ductility of at least 0.5%, and a tensile strength of at least 10 kg/mm.sup.2 and derived from acrylonitrile-based fibers. The spun yarn has a twist coefficient of 30 to 60.

Abstract: Fibrous activated carbon having a pH not more than 5 which is suitable for recovering halogenated hydrocarbon solvents is disclosed. The fibrous activated carbon is obtained by acid treating raw fibrous activated carbon.

Abstract: A prepreg for making a composite is disclosed. The prepreg comprising reinforcing fibers impregnated with a resin composition comprising (A) an epoxy resin, (B) a reaction product of an epoxy resin and a butadiene-acrylonitrile copolymer having carboxyl groups on at least both terminals of the molecular chain of the copolymer, and (C) 4,4'-diaminodiphenylsulfone as a curing agent. A composite produced by curing this prepreg is high in both tensile elongation and heat resistance and is used with advantage as primary and secondary structural materials in aircraft.

Abstract: A carbon fiber coated with 0.3 to 10 wt. % of a polyurethane resin is disclosed. Also disclosed is a carbon fiber reinforced thermoplastic resin composition consisting preferably of 3 to 60 wt. % of such carbon fiber and 97 to 40 wt. % of a thermoplastic matrix resin. Said carbon fiber has increased gathering properties and adhesion strength to facilitate the mixing with the thermoplastic matrix resin and provides a resin molding having improved mechanical properties, especially increased impact strength.

Abstract: Acrylonitrile fibers suitable for production of preoxidized fibers, fibrous active carbon and carbon fibers, which have thereon a water-soluble basic aluminum salt of the formula:Al.sub.2 (OH).sub.l (A).sub.m (B).sub.n (C).sub.p (Cl).sub.q (I)where(1) A, B and C stand for mutually different acid residues;(2) l and q are both an integer or decimal fraction larger than 0;(3) m, n and p are 0 or an integer or decimal fraction and make a total which is not zero;(4) l+mEm+nEn+pEp+q=6 (Em, En and Ep are the valence numbers of A, B and C, respectively); ##EQU1## in an amount of 0.005 to 5.0% by weight of aluminum element based on the fiber having the salt.

Abstract: A heat-moldable laminate comprising at least one thermoplastic resin layer, at least one fiber reinforced cured thermosetting resin layer, and at least one slippage layer interposed therebetween and bonding the resin layers, said slippage layer comprising a thermoplastic resin and said slippage layer being capable of being molten at lower temperatures than the moldable temperature of the thermoplastic resin layer, and a process for molding the heat-moldable laminate to produce a molded article having excellent strength and rigidity is disclosed.

Abstract: A brush, for use for example as an electrical pick-up, includes a brush portion composed of a bundle of metal coated carbon fibers arranged substantially in parallel. A base portion includes a region where the metal coated fibers have been bonded by diffusion via a hot pressing method, and at least one metallic piece bonded to the fiber bundle by diffusion by the same process. The brush of the invention has excellent durability and a conductivity.

Abstract: A rocker arm made from a carbon-fiber reinforced resin is disclosed wherein various axes are defined with particularity such as the central axis of the hole through which the rocker shaft is inserted (Z-axis), a line parallel to the edge of the valve side (Y-axis) and the line that is parallel to the cam side (Y'axis). The bisect of the angle at which the Y-axis crosses the Y'axis is the X-axis. Further, cos.sup.2 .beta. of the carbon fibers present in the Y- or Y'axis side with respect to the X-Z axis is defined in detail where .beta. is a defined angle of orientation as is cos.sup.2 .alpha. which is defined in the specification.The rocker arm is produced by filling a rocker arm mold with a carbon fiber-containing synthetic resin such that cos.sup.2 .beta. of the carbon fibers meets a defined value to such an extent that the cos.sup.2 .alpha. meets a defind value. The rocker arm is lighter and stronger than conventional rocker arms.

Abstract: A fibrous activated carbon with a metal chelate compound supported thereon which is suitable for removal of toxic substances in gas. This activated carbon is obtained by attaching a solution or dispersion of the metal chelate compound onto the fibrous activated carbon followed by drying. Contacting the activated carbon with a toxic substance-containing gas provides very efficient removal of the toxic substance from the gas.

Abstract: A fibrous activated carbon having high adsorptivity and excellent mechanical properties is produced by preoxidizing an acrylonitrile-based fiber containing a specific amount of an iron compound at a specific initial heat-treatment temperature and then activating.

Abstract: A carbon fiber, a process for production thereof, and composite materials prepared therewith are described, wherein the carbon fiber has a single yarn diameter of from 2 to 6 microns and showing a strand knot strength of 7 kilograms or more when formed into a strand of 0.4.+-.0.01 gram per meter, which comprises subjecting a 0.1 to 0.6 denier acrylonitrile-based fiber having a strength of 6 grams per denier or more to a preoxidation treatment wherein the acrylonitrile-based fiber is treated under such tension as to provide a shrinkage of at least 3% until the equilibrium water content reaches 5%, and (b) a second preoxidation treatment wherein the acrylonitrile-based fiber is treated under such tension as to provide a shrinkage of at least 1%, said preoxidation treatment is conducted in an oxidizing atmosphere having a temperature of from 240.degree. C. to 300.degree. C. while maintaining the relation between the preoxidation treatment time (t) (minutes) and average preoxidation treatment temperature (T) (.

Abstract: A friction material comprising a carbon fiber reinforced carbon with an oxidation temperature of at least 800.degree. C. and a crystallinity index of matrix carbon of from 2.3 to 5.0, a process for the production of the same, and a friction element comprising the same.