US4076894A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical circuit element comprising thick film resistor bonded to conductor
Assignee: Engelhard Minerals and Chemicals Corp
•
Filing: 1975-10-28
•
Granted: 1978-02-28
•
Expires: 1995-10-28
Abstract
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.
Inventors
- 👤 Robert C. Langley
- 👤 Muriel Abrash
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 21:45
CPC Classifications
H; H01; H01C; H01C17/00; H01C17/06; H01C17/065; H01C17/06506; H01C17/06513; H01C17/06533; H01C17/0654; C; C03; C03C; C03C3/00; C03C3/04; C03C3/062; C03C3/07; Y; Y10; Y10S; Y10S428/00; Y10S428/901
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
124 words
An electrical circuit element comprising a thick film resistor comprising preformed glass frit, wherein the glass frit is produced by 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, said resistor being bonded to a conductor comprising glass frit and a sufficient amount of an electrically-conductive component to provide the desired electrical properties.
Claim 2
Dependent Claim
124 words
An electrical circuit element comprising a thick film resistor comprising preformed glass frit, wherein the glass frit is produced by 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, said resistor being bonded to a conductor comprising glass frit and a sufficient amount of an electrically-conductive component to provide the desired electrical properties.
Claim 3
Dependent Claim
13 words
The electrical circuit element of claim 1 wherein the electrically-conductive component is platinum.
Claim 4
Dependent Claim
97 words
The electrical circuit element of claim 1 wherein the glass frit in the conductor is produced by 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.
Claim 5
Dependent Claim
13 words
The electrical circuit element of claim 3 wherein the electrically-conductive component is platinum.
References Cited (Backward Citations)
US3304199A
Cited
US3293501A
Cited
US3352797A
Cited
US3324049A
Cited
US3655440A
Cited
US3830651A
Cited
US3682840A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-02-27 | 1981-08-29 | 1982-02-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-27 | 1985-08-29 | 1986-02-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-27 | 1989-08-29 | 1990-02-28 | $7700.00 | Window Closed / Lapsed |