Abstract: A metal oxide vapor, such as tungsten oxide, is reacted with a ceramic material, such as aluminum oxide, at a temperature in the range of from about 1300.degree.C to about 1400.degree.C. The metal oxide vapors diffuse into the ceramic material during the reaction. The ceramic material, which now includes tungsten oxide diffused therein, is then subjected to a reducing atmosphere so as to form a cermet region in the ceramic material.

Abstract: A method of making a voltage sensitive switch characterized by an irreversible change in resistance from a high resistance state greater than one megohm to a low resistance state less than approximately one hundred ohms is described as comprising heating substantially pure grade copper in an oxidizing environment for a sufficient time to oxidize the outer surface of the copper powder, mixing the oxidized copper powder with a binder and applying the mixture to a pair of spaced electrodes.

Abstract: A method of making a voltage sensitive switch characterized by an irreversible change in resistance from a high resistance state greater than one megohm to a low resistance state less than one thousand ohms is described as comprising mixing substantially pure grade copper powder with copper oxide powder, adding a binder to the mixture and applying the resulting mixture to a pair of spaced electrodes.

Abstract: A method for coating only the element of an electronic device such as resor, diode or the like having an attached lead or leads with a powder coating. In this method, the electronic device travels on conveying apparatus from one end to the other end thereof, the lead holding the electronic device stably thereon. The electronic device is preliminarily heated during said travel by a preheating furnace thereby partially melting the powder coating which is applied to said device in the following part of the travel, the partially stuck powder coating on said electronic device being cured by passing the device through a secondary heating furnace thereby making it possible to complete the coating of the powder coating on the electronic device.

Abstract: A resistor comprising a layer of material disposed on a substrate which layer contains a metal component which can be either a pure metal or a metal alloy and which has carbon inserted therein to vary the specific resistance and the temperature coefficient of the electrical resistance. The method of producing the resistor comprises providing a metal-organic compound such as nickel acetylacetonate which is evaporated and carried by a carrier gas, such as hydrogen or ammonia, to a heated substrate. When the vaporized metal-organic compound contacts the heated substrate it decomposes to provide a layer having a metal component with carbon inserted in the component. By controlling the temperature of the heated substrate and by controlling the pressure of the carrier gas, the volume percent of carbon inserted into the metal component when forming the layer can be controlled to vary both the specific resistance of the layer and the temperature coefficient of the electrical resistance.

Abstract: Method for producing a metal film resistor by (1) treating a base material with a stannous chloride solution, silver salt solution and palladium chloride solution, respectively, (2) subjecting the thus treated base material to electroless plating in a bath having a pH of 9.5-10.5 containing specified amounts of cobalt salts, nickel salts, sodium hypophosphite and specific acetifying agents, at a temperature of 20.degree.-50.degree.C, (3) heat treating the resultant metal film under specified conditions, which are also effective to prevent oxidation of the film and (4) subjecting the heattreated metal film to a surface treatment under specified conditions, which are also effective to cause oxidation of the film.

Abstract: An improved process for the production of carbon-containing glass resistors comprising impregnating porous glass with a furfuryl alcohol solution, polymerizing the furfuryl alcohol retained in the glass by contacting the glass with hydrochloric acid to produce a resin, drying the glass to remove moisture therefrom, and firing the glass in a non-oxidizing atmosphere to convert the resin to carbon, is described. Substantially improved yields of high value resistors are obtained by the process.

Abstract: An improved process for the production of carbon-containing glass resistors comprising impregnating porous glass with a furfuryl alcohol solution, flash-heating the impregnated glass at temperatures in the range of 150.degree.-225.degree.C. to polymerize the alcohol to a resin, and firing in a non-oxidizing atmosphere to convert the resin to carbon, is described. Substantially improved yields of high value resistors are obtained by the process.