Abstract: Novel copper-silver metallic films are prepared on transparent articles by chemical replacement of silver for copper according to the method of the present invention. A transparent article is coated with a metallic copper film by a conventional method of deposition. The copper coated article is then contacted by a solution comprising a silver salt, ammonia and a complexing agent which promotes replacement but which does not accelerate the oxidation of residual metallic copper in the film. Replacement of copper by silver occurs with the film retaining its reflective metallic character.
Abstract: A positive containment threshold for use in an apparatus for manufacturing flat glass includes a metal base with a combination of vertically disposed members for connection to a bottom casing of a glass forming chamber. Disposed adjacent a vertical member which serves as an end wall casing member in the combination is at least one refractory threshold block which provides a smooth glass contact surface over which molten glass may be delivered onto a pool of molten metal contained within the bottom portion of an enclosed forming chamber. This threshold in combination with the casing surrounding the bottom portion of an enclosed forming chamber provides an impervious barrier to prevent the inadvertent loss of molten metal from the container in the event of refractory failure.
Abstract: Thin films containing metallic silver and nickel are deposited on transparent articles according to the method of the present invention. A nickel-coated glass article having a reflective gray appearance is contacted with a solution comprising water, a silver salt and a complexing agent. The resultant article has a low reflectance surface, the color of which appears brown-gray to gray in fluorescent lighting.
Abstract: Multiple layer films of silver-silver oxide and metal oxide are produced on transparent substrates for purposes of solar energy control and production of architectural colors. Solar control properties and the transmitted and reflected colors of the article can be altered by varying the thicknesses of the films and/or the selection of metal oxide overcoat.The article produced can be used in a viewing closure and as a component in a solar energy collection system.
Abstract: The glass forming chamber in which glass is formed into a continuous sheet by floating it on the surface of molten metal is provided with a series of heat exchangers in an enclosed shell above the chamber and protective atmosphere gases are passed through these heat exchangers to preheat the atmosphere gases which are then directed through conduits into headers and distribution manifolds located within the headspace of the operating portion of the chamber in the vicinity of the glass being formed. The chamber is provided with conventional electrical heating elements connected to bus bars located within the shell containing the heat exchangers, and the heat exchangers are located close to the bus bars to extract heat from them during operation and thereby prolong their useful lives.
July 16, 1975
Date of Patent:
August 24, 1976
PPG Industries, Inc.
John W. Kompare, John C. Potts, James L. Simpson
Abstract: In the manufacture of flat glass, molten glass is delivered along a substantially horizontal delivery path onto a pool of molten metal. A stream of molten glass is deeper along its marginal portions than its central portion in order to provide for substantially uniform flow rates across the entire stream of molten glass. A continuous ribbon of flat glass of any thickness may be uniformly formed in a very short distance extending downstream from the delivery as a result of delivering the glass in this manner.
Abstract: A metal reactant, dissolved in a volatile solvent, is sprayed into converging reactive carrier gas streams, is vaporized and is carried past a heater for ultimate discharge against a heated substrate whereupon the metal reactant and a portion of the reactive gas streams react to form an adherent coating on the substrate.
Abstract: A glass forming chamber in which glass is formed into a continuous sheet by floating it on the surface of molten metal is provided with a first protective atmosphere gas in an enclosed shell above a refractory roof in the chamber and with a second protective atmosphere gas in the headspace of the operating portion of the chamber in the vicinity of the glass being formed. The second protective atmosphere gas is more reducing than the first. For example, the first protective atmosphere gas may be nitrogen while the second protective atmosphere gas is a mixture of nitrogen and hydrogen.
Abstract: Applying a coating composition onto a linearly advancing substrate from at least two spray guns which cyclically traverse the substrate in the direction perpendicular to the movement of the substrate, and which are spaced so as to satisfy the harmonic relationships between the speed of the advancing substrate, the frequency of the spray gun cycles and the spacing of the spray patterns at the surface of the advancing substrate, as defined by the following equation: ##EQU1## WHEREIN: S.sub.p = the spacing between the lines of intersection of the surface plane of the advancing substrate and the imaginary planes generated by the transversely moving axes of adjacent spray patterns, in inches;R.sub.s = substrate or ribbon speed, in inches per minute;N.sub.g = the number of spray guns;n = any positive or negative whole integer other than n=Ng or multiples of n=Ng; andF.sub.m = the cycle speed or frequency of reciprocation of the spray guns, in cycles per minute.
Abstract: An optically clear, electrically conductive, transparent coating on a substrate and a method of coating are disclosed. The coating comprises a first transparent layer deposited as TiO.sub.x on the substrate, where x preferably has a value within the range of 1.3 to 1.7, a layer of silver or gold deposited on the first layer, and a third transparent layer deposited as TiO.sub.x on the second layer, where x preferably has a value within the range of 1.3 to 1.7. The coating is deposited under vacuum in a partial pressure of oxygen on a rigid transparent substrate such as glass or a flexible plastic substrate and the resultant coated substrate used in electrically heated windows.
Abstract: A metal oxide coating is applied to a hot glass surface by contacting the surface with a mixture of carrier air, vaporized solvent and a vaporized metal containing reactant. The mixture is directed against the glass through an elongated, converging slot-nozzle, the interior surfaces of which have an increasing radius of curvature towards the exit end, nozzle at a Reynolds number exceeding 2500 with the nozzle-to-glass spacing at least 1.25 times the characteristic dimension of the nozzle.
Abstract: A guide bar for stabilizing the position and orientation of a continuous sheet of flat glass being conveyed upwardly from a forming chamber comprises a transverse element located adjacent the continuous sheet of glass and spaced from it. The guide bar is preferably cooled or otherwise provided with means for controlling its temperature.
Abstract: A metal oxide coating is applied to a hot glass surface by contacting the surface with a mixture of carrier air, vaporized solvent and a vaporized metal containing reactant. The mixture is directed against the glass through an elongated converging nozzle having a contraction ratio of six or greater and having walls so shaped with increasing radii of curvature that a fluid flowing adjacent the walls through the nozzle is accelerated substantially throughout its passage through the nozzle.
Abstract: Flat glass is produced by advancing a layer of molten glass on the surface of molten metal while cooling it sufficiently to form a continuous sheet of glass which is lifted upwardly from the surface of the supporting pool of molten metal and conveyed upwardly from it for further processing. A method is provided for selectively controlling the temperature, and thus the viscosity, of the glass of selected portions across the width of the continuous sheet of glass in order to adjust and maintain the relative lengths of the respective portions of the continuous sheet of glass as it is lifted upwardly from the supporting pool of molten metal and to thereby control the flatness of the continuous sheet of glass as it is ascending from the supporting pool of molten metal.
October 15, 1974
Date of Patent:
February 24, 1976
PPG Industries, Inc.
Joseph A. Gulotta, Leonard A. Knavish, John E. Sensi
Abstract: A multiple glazed glass article including two glass panels separated by a spacer and held in a marginal frame is disclosed. Two coatings are present on one of the glass panels providing the article with useful and esthetic reflective and transmission properties. One coating preferably includes a metal such as silver, chromium, iron, cobalt or nickel and the other coating preferably includes a metal oxide such as iron oxide or copper oxide. The metal oxide layer is essentially the oxide of a metal other than the metal of the metal layer.
Abstract: Thermal convection currents in the headspace above a body of glass being formed into a continuous sheet of glass while supported on molten metal are controlled to prevent the development of surface distortion patterns in the upper surface of the glass being formed. This is accomplished by establishing a series of small convection cells at least adjacent the upper surface of the glass so that the characteristic convective cooling rate for the glass in the forming chamber is substantially diminished, particularly near the inlet end of the forming chamber.
May 30, 1974
Date of Patent:
January 27, 1976
PPG Industries, Inc.
William J. Muhlstadt, James R. Schornhorst
Abstract: A layer of molten glass is discharged from a pool of molten glass in a glassmaking furnace and delivered along a substantially horizontal path onto a pool of molten metal in a forming chamber; the glass is then advanced along the surface of the pool of molten metal while being cooled to form a continuous sheet of glass. Prior to discharge and delivery, the molten glass is conditioned to establish an accelerated flow of molten glass in the direction of its delivery. The glass is conditioned by selectively cooling the glass at different depths in the pool of molten glass across the width of the delivery path just prior to delivery to preferentially decelerate the flow of hotter, less viscous glass at one location in the pool of molten glass relative to the flow of cooler, more viscous glass at another location in the pool. In this way the molten glass is caused to uniformly flow into a region for discharge from the pool and delivery for forming.
Abstract: Glass advancing along the surface of a pool of molten metal and being formed into a continuous sheet of flat glass is controllably cooled by advancing over successive molten metal containing compartments partially separated from one another by barriers and each provided with individually controllable cooling facilities.
Abstract: Flat glass is produced by advancing a layer of molten glass along the surface of molten metal while cooling it sufficiently to form a continuous sheet of glass which is lifted upwardly from the surface of a supporting pool of molten metal and conveyed from it for further processing. The molten metal substantially immediately beneath the location at which the glass is lifted upwardly from the pool of molten metal is cooled to a temperature below that of a surrounding molten metal in order to provide for the free release of the formed sheet of glass from the molten metal and to provide for the production of an extremely flat sheet of glass.