Glass frit containing lead ruthenate or lead iridate in relatively uniform dispersion and method to produce same
AssigneeEngelhard Minerals & Chemicals Corporation
InventorsRobert C. Langley, Muriel Abrash
Life of this patent
Estimating the term…
Abstract
Thick film resistive elements are prepared from an intimate admixture comprising silica, lead oxide and ruthenium dioxide or iridium dioxide which is heated to a temperature sufficient to provide a lead-containing glass having dispersed therein lead ruthenate or lead iridate. The lead-containing glass is comminuted and a resistor paste is formed which can be subsequently coated and fired on to a desired substrate to form the thick film resistive component. The method of this invention may facilitate the production of thick film resistors exhibiting a low temperature coefficient of resistivity, relative freedom from noise and drift, and high moisture resistance.
Claims20
A method of making a glass frit suitable for use in the production of thick film resistors comprising heating a finely-divided mixture of glass-forming proportions of lead oxide and silica, and a minor amount of a member selected from the group consisting of ruthenium dioxide and iridium dioxide to a temperature sufficient to form a glass melt containing lead ruthenate or lead iridate, whereat the viscosity of the melt is sufficiently high to maintain the lead ruthenate or lead iridate in relatively uniform dispersion in the glass melt, cooling and comminuting the mixture to provide the glass frit.
Dependencies are inferred from the claim text.