US4906406A
Expired / Lapsed
US
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Thermistor composition
Assignee: EIDP Inc
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Filing: 1988-07-21
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Granted: 1990-03-06
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Expires: 2008-07-21
Abstract
Abstract The invention is directed to a thick film thermistor composition consisting of finely divided particles of (a) a ruthenium-based pyrochlore, and (b) a short borosilicate glass or glass mixture, both dispersed in (c) an organic medium.
Inventors
- 👤 Jacob Hormadaly
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 11:36
CPC Classifications
H; H01; H01C; H01C7/00; H01C7/02; H01C7/021; C; C03; C03C; C03C3/00; C03C3/04; C03C3/062; C03C3/064; C03C3/066; C03C3/07; C03C3/072; C03C8/00; C03C8/02; C03C8/10; C03C8/14; C03C8/20; C03C8/22; H01C17/00; H01C17/06; H01C17/065; H01C17/06506; H01C17/06573; H01C17/0658
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
164 words
A thick film thermistor composition consisting essentially of admixture of finely divided particles of (a) 5-60% wt. of ruthenium-based pyrochlore; (b) 95-40% wt. of a borosilicate glass or mixture of glasses containing by mole %, basis total glass, (1) 65-85% glass-forming oxides containing 25-55% B 2 O 3 , 40-10% SiO 2 and 30-0% other glass-forming oxides selected from Al 2 O 3 , ZrO 2 and mixtures thereof, and (2) 35-15% glass modifying oxides consisting essentially of 3-35% alkaline earth metal oxide(s) of which no more than about 10% is MgO and 0-28% replacement oxide(s) selected from the group consisting of CuO, Cu 2 O, PbO, ZnO and mixtures thereof, of which none exceeds 10% and the total of which does not exceed 80% of the total glass modifying oxides, the viscosity of the glass upon firing at a peak temperature of 700°-1000° C. being from 10 to 10,000 poises, both of components (a) and (b) being dispersed in (c) an organic medium.
Claim 2
Dependent Claim
164 words
A thick film thermistor composition consisting essentially of admixture of finely divided particles of (a) 5-60% wt. of ruthenium-based pyrochlore; (b) 95-40% wt. of a borosilicate glass or mixture of glasses containing by mole %, basis total glass, (1) 65-85% glass-forming oxides containing 25-55% B 2 O 3 , 40-10% SiO 2 and 30-0% other glass-forming oxides selected from Al 2 O 3 , ZrO 2 and mixtures thereof, and (2) 35-15% glass modifying oxides consisting essentially of 3-35% alkaline earth metal oxide(s) of which no more than about 10% is MgO and 0-28% replacement oxide(s) selected from the group consisting of CuO, Cu 2 O, PbO, ZnO and mixtures thereof, of which none exceeds 10% and the total of which does not exceed 80% of the total glass modifying oxides, the viscosity of the glass upon firing at a peak temperature of 700°-1000° C. being from 10 to 10,000 poises, both of components (a) and (b) being dispersed in (c) an organic medium.
Claim 3
Dependent Claim
33 words
The composition of claim 1 in which the ruthenium-based pyrochlore is selected from the group consisting of Pb 2 Ru 2 O 6 , Bi 2 Ru 2 O 7 and mixtures thereof.
Claim 4
Dependent Claim
34 words
The composition of claim 1 in which the composition contains up to 15% wt. metal oxide additive selected from the group consisting of CuO, Cu 2 O, ZrSiO 4 and mixtures and precursors thereof.
Claim 5
Dependent Claim
36 words
The composition of claim 1 in which the glass has the composition by mole % 5.0% Al 2 O 3 , 55.0% B 2 O 3 , 15% SiO 2 , 20% BaO and 5% MgO.
Claim 6
Dependent Claim
33 words
The composition of claim 1 in which the glass has the composition by mole % 55.0% B 2 O 3 , 20.0% SiO 2 , 10.0% BaO and 5.0% MgO and 10.0% SrO.
Claim 7
Dependent Claim
51 words
The composition of claim 3 in which the glass has the composition by mole % 4.3% Al 2 O 3 , 47.3% B 2 O 3 , 17.4% SiO 2 , 4.5% ZrO 2 , 17.2% BaO and 2.1% MgO and the composition also contains 6.7% ZnO and 0.5% copper oxide.
Claim 8
Dependent Claim
57 words
The composition of claim 3 in which the glass has the composition by mole % 4.3% Al 2 O 3 , 42.3% B 2 O 3 , 5.0% Bi 2 O 3 , 17.4% SiO 2 , 4.5% ZrO 2 , 17.2% BaO and 2.1% MgO and the composition also contains 6.7% ZnO and 0.5% copper oxide.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1993-03-05 | 1993-09-04 | 1994-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-03-05 | 1997-09-04 | 1998-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-03-05 | 2001-09-04 | 2002-03-06 | $7700.00 | Window Closed / Lapsed |