| 摘要 |
1,247,095. Resistors. W. PREH, [trading as PREH ELEKTROFEINMECHANISCHE WERKE JAKOB PREH NACHFOLGER]. 12 Nov., 1969 [16 Nov., 1968], No. 55474/69. Heading H1S. In a film resistor comprising conductive particles in a non-conductive material, the non- conductive material is a synthetic polymer capable of being cross-linked by irradiation, so that the film may be hardened quickly without the action of heat. The radiation may be X-rays, y-rays, electrons, neutrons, protons or α- particles, with a dose in the range 1 to 30 megarad. The polymer used may be acryl monomer-polymer mixtures, acryl polyester resins, acrylically modified epoxy resins or unsaturated polyester resins. The conductive particles, added in a volume concentration of 15-85%, may be finely divided metals, e.g. Fe, Cu, Cr, Al, Ag, Au, or their alloys, with particle sizes 10-100 Á; or they may be finely-divided graphite, or acetylene carbon black with a specific surface 80-150 m.<SP>2</SP>/g. For high resistance resistors semi-conductive particles (metal oxides, e.g. SnO 2 or Sb 2 O 3 , or sulphides, e.g. CdS and PbS) may be added together with the conductive particles, in such proportions that the total filler volume concentration is 25-50%. For resistors to be used as slide rheostats &c., substances having a dihexagonal-bipyramidal crystal structure may be added in volume concentration 1-10% to improve sliding properties and reduce wear. Of such substances, graphite will serve simultaneously as conductive material and molybdenum disulphide as semiconductive material. Details are given in the Specification of the production of the conductive particles, the mixing of the particles and the other material, the polymerization process, and the acceleration, deflection &c. of the electron beam. |
