Patent US3772041A successfully refreshed from Google Patents.
US3772041A
Expired / Lapsed
US
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Vitroceramics
Assignee: Saint Gobain Industries SA
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Filing: 1971-05-24
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Granted: 1973-11-13
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Expires: 1991-05-24
Abstract
Abstract Translucent and opaque vitroceramics of fine grain and high quality are produced from compositions having 90 percent or more of 4-5 specific oxides with the exclusion of all but minor percentages of other ingredients. The invention describes the raw materials, the composition of the glass from which the vitroceramics are made, and the novel processes by which they are produced.
Inventors
- 👤 J Tochon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 08:01
CPC Classifications
C; C03; C03C; C03C10/00; C03C10/0036
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
26 words
Strong vitroceramics having a softening point above 1,350*C. and consisting essentially, by weight, of SiO2 25-28 percent Al2O3 38-44 percent, CaO 20-26 percent, ZrO2 9-12 percent.
Claim 2
Dependent Claim
31 words
A vitroceramic body according to claim 1, having a softening point at least about 1,350*C., containing crystals of pure ZrO2 and crystals of anorthite, and being opaque and of white color.
Claim 3
Dependent Claim
31 words
A vitroceramic body according to claim 1, having a softening point at least about 1,350*C., containing crystals of pure ZrO2 and crystals of gehlenite, and being opaque and of white color.
Claim 4
Dependent Claim
75 words
A vitroceramic body consisting essentially of at least 90 percent by weight of SiO2, Al2O3, Cao with or without MgO, and ZrO2, in the following proportions by weight SiO2 26-30% Al2O3 45-50% CaO 10-16% ZrO2 8-12% MgO, if present, not exceeding 3 percent of the weight of the body and the ratio of MgO/CaO being less than 0.15, and Na2O and K2O, if present, not exceeding 3 percent of either nor 4 percent for both.
Claim 5
Dependent Claim
22 words
Highly refractory vitroceramics consisting essentially, by weight of SiO2 26-30 percent by weight Al2O3 45-50 percent, CaO 10-16 percent, ZrO2 8-12 percent.
Claim 6
Dependent Claim
31 words
A vitroceramic body according to claim 5, having a softening point at least about 1,350*C., containing crystals of pure ZrO2 and crystals of anorthite, and being opaque and of white color.
Claim 7
Dependent Claim
31 words
A vitroceramic body according to claim 5, having a softening point at least about 1,350*C., containing crystals of pure ZrO2 and crystals of gehlenite, and being opaque and of white color.
Claim 8
Dependent Claim
19 words
Translucent vitroceramics consisting essentially, by weight, of SiO2 25-35 percent Al2O3 40-50 percent, CaO 10-20 percent, ZrO2 8-12 percent.
Claim 9
Dependent Claim
33 words
A white opaque vitroceramic having the composition, by weight, of SiO2 25-35 percent. Al2O3 40-50 percent, CaO 10-20 percent, ZrO2 8-12 percent said constituents constituting at least about 90 percent of its weight.
References Cited (Backward Citations)
US3007804A
Cited
DE1471337A1
Cited
US3205079A
Cited
GB986289A
Cited
GB1133010A
Cited
FR1474487A
Cited
US3486963A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-12 | 1977-05-14 | 1977-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-12 | 1981-05-14 | 1981-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-12 | 1985-05-14 | 1985-11-13 | $7700.00 | Window Closed / Lapsed |