GB724086A - Articles provided with electroconductive coatings - Google Patents

Abstract

724,086. Electric heating. PITTSBURGH PLATE GLASS CO. April 30, 1951, No. 10093/51. Class 39 (3) [Also in Group XXXVI] An electroconductive article comprises a transparent glass or refractory base, a transparent electroconductive coating on the base, and a bus-bar consisting of electroconductive metal particles in a vitrifying binder adherently bonded to the coated base and in electrical contact with the coating. A panel suitable for use as an automobile windshield consists of a glass sheet 7 with bus-bars 3 of ceramic silver composition and an electroconductive film 9 of tin oxide. The bus-bars are connected to an electric potential source 19 and the heating of the panel may be controlled by a thermostat. In Fig. 4 a further coating 13 of conductive metal paint such as an air drying cement including conductive metal powder is applied as shown. Alternatively, a reinforcing layer of copper, silver &c., may be applied by electro-deposition, &c. In Fig. 3 the bus-bar is applied to a conductive coating 9 and a further coating 11 then added. The inner edge of the bus-bars may have a gold coating. A window, Figs. 6 and 8, consists of glass sheets 30, 32 with a transparent interlayer 34 such as polyvinvl butyrol which projects and provides a rim 36 which is reinforced by aluminium strips 38. Sheet 32 has an electroconductive coating on its inner surface and bus-bars 3 extend along opposite edges and have terminals 40 embedded in the interlayer, and contact with the bus-bars is effected through conductors 42. A resistor may be placed against the window and connected to terminals 44 in the rim so that its resistance will be a function of the window temperature, and the potential across the bus-bars may be controlled in accordance with this temperature by placing the resistor in an auxiliary circuit including relays, etc., whereby the heating current may be inter rupted. In Figs. 10-12, a panel consists of glass sheets 50, 52 cemented together by a plastic layer 54 such as polyvinyl butyrol &c., and the inner surface of sheet 52 has an electroconductive coating and bus-bars 56. Two conductive coatings 60 extend over the edge of plate 52 and are in contact with the bus-bars.The panel is mounted in a rubber or like channel member 70 and electrical contact is made through a conductor 80 terminating in a spring contact 81. The metal particles of the bus-bars may be of silver, gold, platinum, indium, irridium, rhodium, tungsten, &c. The transparent electroconductive coatings may comprise compounds of metals such as the chlorides, bromides, acetates or nitrates of thallium, indium, lead, magnesium, molybdenum, selenium, strontium, tungsten, &c., and some of these metals may be deposited in elemental state by vapour deposition or a spluttering process. Specifications 556,035, 576,095, [both in Group VIII], and 724,087 and U.S.A. Specification 2,118,795 are referred to.