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US4065743A
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US
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Resistor material, resistor made therefrom and method of making the same
Assignee: Northrop Grumman Space and Mission Systems Corp
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Filing: 1975-03-21
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Granted: 1977-12-27
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Expires: 1995-03-21
Abstract
Abstract A vitreous enamel resistor material comprising a mixture of a vitreous glass frit and fine particles of a mixture of tin oxide (SnO 2 ) and tantalum oxide (Ta 2 O 5 ). An electrical resistor is made from the resistor material by applying the material to a substrate and firing the coated substrate to a temperature at which the glass melts. The oxide mixture may be heat treated prior to mixing with the glass frit. Upon cooling, the substrate has on the surface thereof a film of the glass having the particles of the oxides embedded therein and dispersed therethroughout. The resistor material provides a resistor having a high resistivity and a low temperature coefficient of resistance.
Inventors
- 👤 Richard L. Wahlers
- 👤 Kenneth M. Merz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:46
CPC Classifications
H; H01; H01C; H01C17/00; H01C17/06; H01C17/065; H01C17/06506; H01C17/06513; H01C17/06533; H01C7/00; H01C7/06; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49082; Y10T29/49099
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
63 words
A vitreous enamel resistor material comprising a mixture of a glass frit and particles of a conductive phase, said conductive phase being selected from the group consisting essentially of (1) a mixture of tin oxide and tantalum oxide, and (2) a mixture of tin oxide, tantalum oxide and the products resulting from heat treatment of said mixture of tin oxide and tantalum oxide.
Claim 2
Dependent Claim
63 words
A vitreous enamel resistor material comprising a mixture of a glass frit and particles of a conductive phase, said conductive phase being selected from the group consisting essentially of (1) a mixture of tin oxide and tantalum oxide, and (2) a mixture of tin oxide, tantalum oxide and the products resulting from heat treatment of said mixture of tin oxide and tantalum oxide.
Claim 3
Dependent Claim
26 words
A vitreous enamel resistor material in accordance with claim 1 in which the glass frit is present in the amount of 30 to 70% by volume.
Claim 4
Dependent Claim
26 words
A vitreous enamel resistor material in accordance with claim 2 in which the glass frit is present in the amount of 40 to 60% by volume.
Claim 5
Dependent Claim
25 words
A vitreous enamel resistor material in accordance with claim 2 in which the conductive phase includes 0.5 to 50% by weight of the tantalum oxide.
Claim 6
Dependent Claim
26 words
A vitreous enamel resistor material in accordance with claim 4 in which the conductive phase comprises a mixture of the tin oxide and the tantalum oxide.
Claim 7
Dependent Claim
33 words
A vitreous enamel resistor material in accordance with claim 4 in which the conductive phase includes the products resulting from a heat treatment of a mixture of tin oxide and the tantalum oxide.
Claim 8
Dependent Claim
19 words
A vitreous enamel resistor material in accordance with claim 4 in which the glass frit is a borosilicate glass.
Claim 9
Dependent Claim
21 words
A vitreous enamel resistor material in accordance with claim 7 in which the glass frit is an alkaline earth borosilicate glass.
Claim 10
Dependent Claim
77 words
An electrical resistor comprising a ceramic substrate and a layer of a resistor material on a surface of said substrate, said resistor material comprising particles of a conductive phase selected from the group consisting essentially of (1) a mixture of tin oxide and tantalum oxide, and (2) a mixture of tin oxide, tantalum oxide and the products resulting from heat treatment of said mixture of tin oxide and tantalum oxide embedded in and dispersed throughout a glass.
Claim 11
Dependent Claim
77 words
An electrical resistor comprising a ceramic substrate and a layer of a resistor material on a surface of said substrate, said resistor material comprising particles of a conductive phase selected from the group consisting essentially of (1) a mixture of tin oxide and tantalum oxide, and (2) a mixture of tin oxide, tantalum oxide and the products resulting from heat treatment of said mixture of tin oxide and tantalum oxide embedded in and dispersed throughout a glass.
Claim 12
Dependent Claim
22 words
An electrical resistor in accordance with claim 9 in which the resistor material contains 30 to 70% by volume of the glass.
Claim 13
Dependent Claim
22 words
An electrical resistor in accordance with claim 10 in which the resistor material contains 40 to 60% by volume of the glass.
Claim 14
Dependent Claim
26 words
An electrical resistor in accordance with claim 10 in which the conductive phase of the resistor material contains 0.5 to 50% by weight of tantalum oxide.
Claim 15
Dependent Claim
28 words
An electrical resistor in accordance with claim 12 in which the conductive phase of the resistor material is a mixture of the tin oxide and the tantalum oxide.
Claim 16
Dependent Claim
35 words
An electrical resistor in accordance with claim 12 in which the conductive phase of the resistor material includes the products resulting from a heat treatment of a mixture of tin oxide and the tantalum oxide.
Claim 17
Dependent Claim
16 words
An electrical resistor in accordance with claim 12 in which the glass is a borosilicate glass.
Claim 18
Dependent Claim
18 words
An electrical resistor in accordance with claim 15 in which the glass is an alkaline earth borosilicate glass.
Claim 19
Independent Claim
92 words
A method of making an electrical resistor comprising the steps of mixing together a glass frit and fine particles of a conductive phase being selected from the group consisting essentially of (1) a mixture of tin oxide and tantalum oxide, and (2) a mixture of tin oxide, tantalum oxide and the products resulting from heat treatment of said mixture of tin oxide an tantalum oxide, applying said mixture to a surface of a substrate, and firing said coated substrate in a substantially inert atmosphere to the melting temperature of the glass frit.
Claim 20
Independent Claim
92 words
A method of making an electrical resistor comprising the steps of mixing together a glass frit and fine particles of a conductive phase being selected from the group consisting essentially of (1) a mixture of tin oxide and tantalum oxide, and (2) a mixture of tin oxide, tantalum oxide and the products resulting from heat treatment of said mixture of tin oxide an tantalum oxide, applying said mixture to a surface of a substrate, and firing said coated substrate in a substantially inert atmosphere to the melting temperature of the glass frit.
Claim 21
Dependent Claim
42 words
The method in accordance with claim 17 in which prior to mixing the conductive phase with the glass frit, the tin oxide and tantalum oxide are mixed together, then heat treated, and then formed into the fine particles of the conductive phase.
Claim 22
Dependent Claim
44 words
The method in accordance with claim 18 in which the conductive phase is heat treated by heating to about 525° C in an atmosphere of forming gas for up to about 10 minutes, and then is cooled while retained in the forming gas atmosphere.
Claim 23
Dependent Claim
34 words
The method in accordance with claim 18 in which the conductive phase is heat treated in a furnace having a nitrogen atmosphere and a peak temperature of about 1000° C for about 1 hour.
Claim 24
Dependent Claim
33 words
The method in accordance with claim 18 in which the conductive phase is heat treated by heating in a nitrogen atmosphere at a temperature of about 1100° C for up to 4 hours.
Claim 25
Dependent Claim
40 words
The method in accordance with claim 20 in which the conductive phase is heat treated by passing the conductive phase through a furnace having a nitrogen atmosphere and a peak temperature of about 1000° C over a 1 hour cycle.
Claim 26
Dependent Claim
91 words
An electrical resistor of the vitreous glaze type made by mixing together a glass frit and fine particles of a conductive phase being selected from the group consisting essentially of (1) a mixture of tin oxide and tantalum oxide, and (2) a mixture of tin oxide, tantalum oxide and the products resulting from heat treatment of said mixture of tin oxide and tantalum oxide, applying said mixture to a surface of a substrate, and firing said coated substrate in a substantially inert atmosphere to the melting temperature of the glass frit.
Claim 27
Dependent Claim
91 words
An electrical resistor of the vitreous glaze type made by mixing together a glass frit and fine particles of a conductive phase being selected from the group consisting essentially of (1) a mixture of tin oxide and tantalum oxide, and (2) a mixture of tin oxide, tantalum oxide and the products resulting from heat treatment of said mixture of tin oxide and tantalum oxide, applying said mixture to a surface of a substrate, and firing said coated substrate in a substantially inert atmosphere to the melting temperature of the glass frit.
Claim 28
Dependent Claim
44 words
An electrical resistor made in accordance with claim 23 in which prior to mixing the conductive phase with the glass frit, the tin oxide and tantalum oxide are mixed together, then heat treated, and then formed into the fine particles of the conductive phase.
Claim 29
Dependent Claim
46 words
An electrical resistor made in accordance with claim 24 in which the conductive phase is heat treated by heating to about 525° C in an atmosphere of forming gas for up to about 10 minutes, and then is cooled while retained in the forming gas atmosphere.
Claim 30
Dependent Claim
36 words
An electrical resistor made in accordance with claim 24 in which the conductive phase is heat treated in a furnace having a nitrogen atmosphere and a peak temperature of about 1000° C for about 1 hour.
Claim 31
Dependent Claim
35 words
An electrical resistor made in accordance with claim 24 in which the conductive phase is heat treated by heating in a nitrogen atmosphere at a temperature of about 1100° C for up to 4 hours.
Claim 32
Dependent Claim
42 words
An electrical resistor made in accordance with claim 26 in which the conductive phase is heat treated by passing the conductive phase through a furnace having a nitrogen atmosphere and a peak temperature of about 1000° C over a 1 hour cycle.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-12-26 | 1981-06-27 | 1981-12-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-12-26 | 1985-06-27 | 1985-12-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-12-26 | 1989-06-27 | 1989-12-27 | $7700.00 | Window Closed / Lapsed |