GB523813A - A method of and apparatus for depositing comminuted material upon backing material - Google Patents

Abstract

523,813. Coated fabrics; sandpaper &c. BEHRMANNING CORPORATION. Jan. 14, 1939, No. 1367. Convention date, Feb. 19, 1938. [Class 140] [Also in Group XXIII] Comminuted material, e.g., abrasive or flock, is deposited upon an adhesively-coated backing material by an electrostatic field in an atmosphere, other than air alone, which ionizes at a higher field intensity than air. The atmosphere may comprise gases. or vapours or mixtures ; specified are nitrogen, nitrous oxide, vapours of methyl chlorides or carbon tetrachloride in air, mixtures of nitrogen with carbon tetrachloride or dichlotofluoromethane and nitrous oxide with carbon tetrachloride trichlorofluoromethane, dichlorotetrafluoroethane, trichlorotrifluoroethane, dichlorodifluoromethane, dichlorofluoromethane, dichloromethane, chlorofluoromethane, chloroform, trichloroacetyl chloride and ethylene chlorhydrin. As shown, paper 1 from a roll 2 is coated on one side with glue in apparatus 6 and passes through a chamber 12 beneath the lower surface of an upper electrode 60, abrasive being supplied from a hopper 46 to a conveyer 52 passing over the upper surface of the lower electrode 61. Unidirectional current of 5,000- 70,000 volts is applied to the electrodes through conductors 70, 71 from a rectifier fed with alternating current; alternating, pulsating direct, or other form of current may be applied. The chamber 12 may be supplied with a suitable gas from a tank 85 or a suitable liquid may be placed in a pan 85a.