US3924221A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Film resistor and method
Assignee: Corning Glass Works
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Filing: 1974-12-16
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Granted: 1975-12-02
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Expires: 1994-12-16
Abstract
Abstract Inexpensive resistor compositions which yield, upon firing, resistors having low TCR values. A temporary binder and finely divided particles of MoO3, a reducing agent and a glass containing PbO are mixed and the resultant paste is applied as a film to a substrate. The substrate and film are heated in an inert gas to a temperature sufficient to cause the PbO, MoO3 and reducing agent to react to form PbMoO4 and MoO2 and to fuse the finely divided particles of glass. The resultant resistive film contains a continuous glassy phase having MoO2 and PbMoO4 particles uniformly dispersed throughout.
Inventors
- 👤 Ernel R Winkler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:31
CPC Classifications
H; H01; H01C; H01C17/00; H01C17/06; H01C17/065; H01C17/06506; H01C17/06513; H01C17/06533; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49082
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
140 words
A METHOD OF MAKING AN ELECTRICAL RESISTANCE ELEMENT COMPRISING THE STEPS OF FORMING A PASTE CONTAINING A TEMPORARY BINDER AND A MIXTURE OF INORGANIC PARTICULATE MATTER, SAID MIXTURE INCLUDING 30- 70 WT. PERCENT GLASS FRIT, THE REMAINDER CONSISTING ESSENTIALLY OF FINELY DIVIDED PARTICLES OF MOO3 AND AN ELEMENTAL REDUCING AGENT, SAID GLASS FRIT CONTAINING LEAD OXIDE IN AN AMOUNT EFFECTIVE FOR YEILDING PBMOO4, THE AMOUNT OF SAID REDUCING AGENT IN SAID MIXTURE BEING SUFFICIENT TO PERMIT THE FORMATION OF MOO2 IN AN AMOUNT SUFFICIENT TO FORM A CONTINOUS CONDUCTIVE PATH AND OF PBMOO4 IN AN AMOUNT EFFECTIVE TO MODIFY THE TEMPERATURE COEFFICIENT OF RESISTANCE OF SAID CONDUCTIVE PATH, APPLYING A FILM OF SAID PASTE TO A REFRACTORY NONCONDUCTIVE SUBSTRATE, AND HEATING SAID SUBSTRATE AND FILM IN AN INERT ATMOSPHERE TO A TEMPERATURE OF AT LEAST 650*C AND WHICH IS SUFFICIENTLY
Claim 2
Independent Claim
140 words
A METHOD OF MAKING AN ELECTRICAL RESISTANCE ELEMENT COMPRISING THE STEPS OF FORMING A PASTE CONTAINING A TEMPORARY BINDER AND A MIXTURE OF INORGANIC PARTICULATE MATTER, SAID MIXTURE INCLUDING 30- 70 WT. PERCENT GLASS FRIT, THE REMAINDER CONSISTING ESSENTIALLY OF FINELY DIVIDED PARTICLES OF MOO3 AND AN ELEMENTAL REDUCING AGENT, SAID GLASS FRIT CONTAINING LEAD OXIDE IN AN AMOUNT EFFECTIVE FOR YEILDING PBMOO4, THE AMOUNT OF SAID REDUCING AGENT IN SAID MIXTURE BEING SUFFICIENT TO PERMIT THE FORMATION OF MOO2 IN AN AMOUNT SUFFICIENT TO FORM A CONTINOUS CONDUCTIVE PATH AND OF PBMOO4 IN AN AMOUNT EFFECTIVE TO MODIFY THE TEMPERATURE COEFFICIENT OF RESISTANCE OF SAID CONDUCTIVE PATH, APPLYING A FILM OF SAID PASTE TO A REFRACTORY NONCONDUCTIVE SUBSTRATE, AND HEATING SAID SUBSTRATE AND FILM IN AN INERT ATMOSPHERE TO A TEMPERATURE OF AT LEAST 650*C AND WHICH IS SUFFICIENTLY
Claim 3
Dependent Claim
25 words
A method in accordance with claim 1 wherein the step of heating comprises subjecting said substrate and film to a temperature between 700* and 900*C.
Claim 4
Dependent Claim
43 words
A method in accordance with claim 2 wherein said step of heating is continued for a period of time between 7 and 12 minutes. 4. A method in accordance with claim 3 wherein said glass frit contains at least 35 wt. percent PbO.
Claim 5
Dependent Claim
26 words
A method in accordance with claim 4 wherein said reducing agent is selected from the group consisting of B, Si, Al, Ge, As, Sb, and Bi.
Claim 6
Dependent Claim
72 words
An electrical resistor of the type comprising a substantially nonconductive substrate having a conductive film on the surface thereof, said conductive film being characterized in that it comprises finely divided particles of MoO2 and PbMoO4 uniformly dispersed in an electrically nonconductive fused glass matrix, said MoO2 constituting the conductive phase of said film and said PbMoO4 being present in an amount effective to lower the temperature coefficient of resistance of said film.
Claim 7
Dependent Claim
72 words
An electrical resistor of the type comprising a substantially nonconductive substrate having a conductive film on the surface thereof, said conductive film being characterized in that it comprises finely divided particles of MoO2 and PbMoO4 uniformly dispersed in an electrically nonconductive fused glass matrix, said MoO2 constituting the conductive phase of said film and said PbMoO4 being present in an amount effective to lower the temperature coefficient of resistance of said film.
References Cited (Backward Citations)
US3304199A
Cited
US3766511A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-01 | 1979-06-02 | 1979-12-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-01 | 1983-06-02 | 1983-12-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-01 | 1987-06-02 | 1987-12-02 | $7700.00 | Window Closed / Lapsed |