摘要:
An electrode comprises a porous carbon sheet comprising (a) carbon fibers and (b) a carbon matrix which comprises carbon particles and is integrally combined with the carbon fibers, having continuous through-holes. This electrode can be used as a cathode or anode for a battery. This type of electrode is prepared by depositing a phenolic resin on a phenolic resin sheet comprising phenolic resin fibers, and carbonizing the phenolic resin and the phenolic resin sheet in an oxygen-free atmosphere at temperatures in the range of 500.degree. C. to 3000.degree. C.
摘要:
The present invention provides a carbonaceous material suitable for an electrode of a secondary cell. The carbonaceous material has a specific surface area by BET method of at least 10 m.sup.2 /g and a nitrogen/carbon atom weight ratio of 0.15 to 0.01, and is obtained by heat-treating a polyimide polymer having repeating units represented by: ##STR1## wherein R represents a 4 valent aromatic residue having at least one aromatic ring, of which each 2 valences are bonded with an adjacent carbon atom in the aromatic ring, R' represents a divalent aromatic residue having 1 to 4 aromatic rings and n is an integer of at least 2. The present invention also provides a secondary cell using the above mentioned carbonaceous material as electrode.
摘要:
The present invention provides a composite sheet electrode which has high strength, excellent current collecting properties and which is used efficiently as an active material for an electrode. The electrode has excellent discharge capacities and can be easily formed into an electrode terminal. A cell employing this electrode is also disclosed. The invention also provides a composite sheet electrode having a porosity of 20 to 80% containing 5 to 95% by weight of an active material of an electrode, 1 to 50% by weight of a current collecting material and heat fusible short fibers. The present invention also provides a composite sheet electrode having a porosity of 20 to 80%, which is made up of a composite sheet containing 5 to 95% by weight of an active material as an electrode and 5 to 95% by weight of heat fusible short fibers, as well as a current collecting material layer formed on said composite sheet. The present invention further provides a cell employing the latter-mentioned composite sheet electrode.
摘要:
A resole resin in the form of microspherical particles whose surfaces are partly or entirely covered with a coating of a substantially water-insoluble inorganic salt and which are not larger than 500 .mu.m in size, and a process for producing such resole resin. The resole resin comprises solid particles that are highly heat reactive and can be stored in a stable manner for a prolonged period. The resin particles can be used with good results in all fields of applications (e.g., moldings, laminations and binders) where conventional phenolic resins are used.
摘要:
A process for producing microspherical cured phenolic resin particles having a particle diameter of not more than about 100 .mu.m, which comprises reacting a novolak resin, a phenol and an aldehyde in an aqueous medium in the presence of a basic catalyst and an emulsion stabilizer. Novel microspherical cured phenolic resin particles are produced by this process. The resin particles have excellent impact strength and mechanical properties, a sharp particle size distribution, and a low secondary agglomerate content, and because of these properties, are useful as an excellent modifier or filler for various plastics and rubbers.
摘要:
A resole resin in the form of microspherical particles whose surfaces are partly or entirely covered with a coating of a substantially water-insoluble inorganic salt and which are not larger than 500 .mu.m in size, and a process for producing such resole resin. The resole resin comprises solid particles that are highly heat reactive and can be stored in a stable manner for a prolonged period. The resin particles can be used with good results in all fields of applications (e.g., moldings, laminations and binders) where conventional phenolic resins are used.
摘要:
The present invention relates to a process for producing spherical thermosetting phenolic resin particles having a size of no larger than about 1,000 microns, and the spherical thermosetting phenolic resin particles produced by this process.In accordance with the process of the present invention, a novolak resin, and a nitrogenous basic compound, and, optionally, an aldehyde, are reacted while they are suspended in an aqueous medium in the presence of a suspension stabilizer.The thermosetting phenolic resin produced by the process of the present invention not only displays superior thermal curing characteristics during molding; the cured product fabricated by molding this resin also exhibits good physical properties such as improved mechanical strength and heat resistance. Therefore, the spherical thermosetting phenolic resin particles produced by the process of the present invention can be extensively used as molding materials, binders, adhesives, and in many other applications.
摘要:
The present invention provides a process for producing a fiber reinforced composite which contains the reinforcing fibers uniformly dispersed therein and therefore has uniformity of strength. The process comprises;preparing an aqueous slurry which comprises reinforcing fibers, water-soluble organic polymers A charged in water and particulate organic polymers,adding thereto water-soluble organic polymers B charged opposite to said organic polymers A in water to flocculate the solid components in said aqueous slurry, andthen removing aqueous medium and molding.
摘要:
A PTC element comprising a conductive sheet of a crystalline polyolefin matrix and a conductive filler, having provided on both sides thereof an electrode of a metallic foil, the PTC element having a resistivity at 20.degree. C. (.rho..sub.20) of not more than 1.8 .OMEGA..multidot.cm, a peak resistivity (.rho..sub.p) of not less than 2.0.times.10.sup.6 .OMEGA..multidot.cm, and a temperature difference �T.sub.a (0.degree.C.)-T.sub.b (.degree.C.)! of not greater than 10.degree. C., wherein T.sub.a (.degree.C.) is a temperature at which the resistivity is 10.sup.6 times the resistivity at 20.degree. C. (.rho..sub.20) and T.sub.b (.degree.C.) is a temperature at which the resistivity is 10 times the resistivity at 20.degree. C. (.rho..sub.20). The PTC element is produced by a process comprising mixing a crystalline polyolefin and a conductive filler, molding the mixture into a conductive sheet, press bonding under heat a metallic foil to both sides of the conductive sheet, and repeatedly subjecting the conductive sheet to a heating and cooling cycle consisting of heating at a temperature of not lower than (the melting point of the crystalline polyolefin minus 5.degree. C.) and then cooling to a temperature lower than (the melting point of the crystalline polyolefin minus 5.degree. C.). The PTC elements exhibit an extremely low resistivity at 20.degree. C. and a high resistivity at a peak temperature, showing a very steep increase in resistance in a narrow temperature range.
摘要:
Disclosed herein are composite carrier particles for electrophotography comprising 80 to 99% by weight of ferromagnetic fine particles and a phenol resin, and having a number-average particle diameter of 10 to 1,000 .mu.m, a bulk density of not more than 2.0 g /cm.sup.3, and a curved surface configuration, and a process for producing the same.