US3899449A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low temperature coefficient of resistivity cermet resistors
Assignee: Globe Union Inc
•
Filing: 1973-05-11
•
Granted: 1975-08-12
•
Expires: 1993-05-11
Abstract
Abstract Cermet resistors based on ruthenium dioxide and in some instances iridium dioxide have been found to have unusually low Temperature Coefficients of Resistivity (TCR) when a particular glass frit and a vanadium oxide additive are utilized. These unique resistors exhibit TCR''s of less than + OR - 25 ppm/*C over -55 to +150*C with the extremes of the TCR varying less than 20 ppm. The vanadium, iridium and ruthenium oxides can be used as such or derived from metal resinates.
Inventors
- 👤 Clifford Joseph Pukaite
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:18
CPC Classifications
H; H01; H01C; H01C17/00; H01C17/06; H01C17/065; H01C17/06506; H01C17/06513; H01C17/06533; H01C17/0654; H01C7/00; H01C7/06
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
122 words
A CERMET RESISTOR COMPOSITION HAVING A LOW TEMPERATURE COEFFICIENT OF RESISTIVITY AN ADAPTED TO BE FUSED TO A SUBSTRATE COMPOSED OF HIGH TEMPERATURE, ELECTRICALLY NONCONDUCTIVE MATERIAL COMPRISING: A CONDUCTIVE PHASE COMPOSED OF VANADIUM OXIDE IN THE RANGE FROM ABOUT 1.00 TO ABOUT 10.00 WEIGHT PERCENT AND RUTHENIUM DIOXIDE IN THE RANGE OF FROM ABOUT 1.00 TO ABOUT 30.00 WEIGHT PERCENT, AND AN INTERDISPERSED GLASS PHASE IN THE RANGE OF ABOUT 50.00 TO ABOUT 98.00 WEIGHT PERCENT, SAID GLASS PHASE COMPOSED OF LEAD OXIDE IN THE RANGE OF ABOUT 35.00 TO ABOUT 45.00 WEIGHT PERCENT, BORON TRIOXIDE IN THE RANGE OF ABOUT 15.00 TO ABOUT 25.00 WEIGHT PERCENT AND SILICON DIOXIDE PRESENT IN THE RANGE OF ABOUT 30.00 TO ABOUT 40.00 WEIGHT PERCENT.
Claim 2
Dependent Claim
122 words
A CERMET RESISTOR COMPOSITION HAVING A LOW TEMPERATURE COEFFICIENT OF RESISTIVITY AN ADAPTED TO BE FUSED TO A SUBSTRATE COMPOSED OF HIGH TEMPERATURE, ELECTRICALLY NONCONDUCTIVE MATERIAL COMPRISING: A CONDUCTIVE PHASE COMPOSED OF VANADIUM OXIDE IN THE RANGE FROM ABOUT 1.00 TO ABOUT 10.00 WEIGHT PERCENT AND RUTHENIUM DIOXIDE IN THE RANGE OF FROM ABOUT 1.00 TO ABOUT 30.00 WEIGHT PERCENT, AND AN INTERDISPERSED GLASS PHASE IN THE RANGE OF ABOUT 50.00 TO ABOUT 98.00 WEIGHT PERCENT, SAID GLASS PHASE COMPOSED OF LEAD OXIDE IN THE RANGE OF ABOUT 35.00 TO ABOUT 45.00 WEIGHT PERCENT, BORON TRIOXIDE IN THE RANGE OF ABOUT 15.00 TO ABOUT 25.00 WEIGHT PERCENT AND SILICON DIOXIDE PRESENT IN THE RANGE OF ABOUT 30.00 TO ABOUT 40.00 WEIGHT PERCENT.
Claim 3
Dependent Claim
25 words
The cermet resistor composition as defined in claim 1 further including iridium dioxide present in the range of about 1.00 to about 15.00 weight percent.
Claim 4
Dependent Claim
76 words
The cermet resistor composition as defined in claim 2 wherein said ruthenium dioxide is present in the range of about 2.00 to about 25.00 weight percent, said iridium dioxide is present in the range of about 3.00 to about 14.00 weight percent, said vanadium oxide is present in the range of about 1.00 to about 8.00 weight percent and said glass phase is present in the range of from about 63.00 to about 95.00 weight percent.
Claim 5
Dependent Claim
61 words
The cermet resistor composition as defined in claim 3 wherein said glass phase is composed of lead oxide present in the range of about 38.00 to about 45.00 weight percent, said boron trioxide is present in the range of about 17.00 to about 21.00 and said silicon dioxide is present in the range of about 33.00 to about 37.00 weight percent.
Claim 6
Dependent Claim
16 words
The cermet resistor composition as defined in claim 2 wherein said vanadium oxide is vanadium pentoxide.
Claim 7
Dependent Claim
27 words
The cermet resistor composition as defined in claim 2 wherein said composition further includes bismuth trioxide present in an amount noT greater than about 10.00 weight percent.
Claim 8
Dependent Claim
27 words
The cermet resistor composition as defined in claim 2 wherein said glass phase contains calcium oxide present in an amount not greater than about 2.00 weight percent.
Claim 9
Dependent Claim
26 words
The cermet resistor composition as defined in claim 7 wherein said calcium oxide is present in the range of about 1.00 to about 2.00 weight percent.
Claim 10
Dependent Claim
26 words
The cermet resistor composition as defined in claim 2 wherein said composition includes aluminum trioxide present in an amount not greater than about 10.00 weight percent.
Claim 11
Dependent Claim
26 words
The cermet resistor composition as defined in claim 9 wherein said aluminum trioxide is present in the range of about 1.00 to about 7.00 weight percent.
Claim 12
Dependent Claim
43 words
The cermet resistor composition as defined in claim 1 wherein said glass phase contains calcium oxide present in the range of about 1.00 to about 2.00 weight percent and aluminum trioxide present in the range of about 1.00 to about 2.00 weight percent.
Claim 13
Dependent Claim
113 words
A starting material composition for manufacturing the composition of claim 1 comprising ruthenium resinate present in the range of about 20.00 to about 85.00 weight percent, iridium resinate present in the range of about 5.00 to about 45.00 weight precent, vanadium oxide present in the range of about 0.50 to 2.50 weight percent and glass frit present in the range of about 5.00 to 40.00 weight percent, said glass frit comprising lead oxide present in the range of about 35.00 to 45.00 weight percent, boron trioxide present in the range of about 15.00 to about 25.00 weight percent and silicon oxide present in the range of about 30.00 to about 40.00 weight percent.
Claim 14
Dependent Claim
22 words
The composition as defined in claim 11 further including bismuth trioxide present in an amount not greater than about 2.25 weight percent.
Claim 15
Dependent Claim
14 words
The composition as defined in claim 11 wherein said vanadium oxide is vanadium pentoxide.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-08-11 | 1979-02-10 | 1979-08-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-11 | 1983-02-10 | 1983-08-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-11 | 1987-02-10 | 1987-08-12 | $7700.00 | Window Closed / Lapsed |