GB694995A - - Google Patents

Abstract

694,995. Electric condensers. WESTERN ELECTRIC CO., Inc. June 15, 1951 [June 15, 1950], No. 14222/51. Class 37. A conducting film is vaporized over a limited area on one side of a dielectric strip, and a solution of a normally solid dielectric material in a volatile solvent is applied over the film and strip, the coating being then evaporated to dryness. Paper from roll 12, Fig. 1, is led under a heated molybdenum wire 21 loaded with silver so that the paper is coated with silver except at the edge where it is masked by 24; the paper then passes over a zinc pot 32 heated by coil 33 so that zinc is vaporized and adheres to the silver coating; the paper is then wound and transferred to roll 15, Fig. 3, where it passes over a roller 47 which is wetted by roller 50 dipping into a tank of lacquer, e.g. cellulose acetate butyrate in methyl acetate; the metallized surface of the paper is thus coated with lacquer, any excess being removed by a scraper roller 49, and passes under drying lamps 59 ... 61, to roll 70. The strip so produced is edge-trimmed at 75, 76, Fig. 4, so that a clean metal surface is exposed at one end. Two such strips placed back-to-back, Fig. 5, are rolled to form a condenser, the exposed metal at each end of the roll having leads affixed. The paper from roll 70 can be similarly coated on both sides, Fig. 8; or it may be repeatedly recoated on the one side, each metallic coating extending to the opposite edge, Fig. 9; or two strips, coated on both sides, may be rolled together, Fig. 10; each of the strips of Fig. 10 may have one of the lacquer coatings dispensed with, Fig. 11; in Fig. 12 a further metal coating has been deposited on the lacquer coating of Fig. 4; in Fig. 13, the paper is first coated with polystyrene 98, then with metal 71 and finally with lacquer 99, the polystyrene being dissolved by benzene to separate the paper and leave a thin metallized lacquer strip; a. lacquer coating may be inserted between the metal 71 and the polystyrene 98. U.S.A. Specification 2,503,571 is referred to.