US3922155A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of making biocompatible glass ceramic
Assignee: Ernst Leitz Wetzlar GmbH
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Filing: 1974-05-21
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Granted: 1975-11-25
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Expires: 1994-05-21
Abstract
Abstract The glass ceramic material of the present invention has the following composition, in weight percent,: ABOUT 20 TO ABOUT 60 PERCENT OF SILICON DIOXIDE SiO2, about 5 to about 40 percent of phosphorus pentoxide P2O5, about 2.7 to about 20 percent of sodium oxide Na2O, about 0.4 to about 20 percent of potassium oxide K2O, about 2.9 to about 30 percent of magnesium oxide MgO, and ABOUT 5 TO ABOUT 40 PERCENT OF CALCIUM OXIDE CaO, and may contain between ABOUT 0.05 AND ABOUT 3.0 PERCENT OF FLUORINE. The glass ceramic material is produced by melting the mixture of components and subjecting the resulting melt to a specific annealing or tempering treatment to cause formation of nuclei and ceramization. Such glass ceramic material is especially useful as bone and tooth replacement material in humans and animals.
Inventors
- 👤 Heinz Broemer
- 👤 Hans-Herbert Kaes
- 👤 Emanuel Pfeil
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:39
CPC Classifications
A; A61; A61L; A61L27/00; A61L27/02; A61L27/12; C; C03; C03C; C03C10/00; C03C10/0009; C03C21/00; A61F; A61F2310/00; A61F2310/00005; A61F2310/00179; A61F2310/00293
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
71 words
MELTING DOWN A MIXTURE ESSENTIALLY CONSISTING, IN WEIGHT PERCENT, OF ABOUT 20 TO BOUT 60 PERCENT OF SILICON DIOXIDE SIO2, ABOUT 2.7 TO ABOUT 20 PERCENT OF SODIUM OXIDE NA2O, ABOUT 0.4 TO ABOUT 20 PERCENT OF POTASSIUM OXIDE K2O, ABOUT 2.9 TO ABOUT 30 PERCENT OF MAGNESIUM OXIDE MGO, ABOUT 5 TO ABOUT 25 PERCENT OF CALCIUM OXIDE CAO, AND ABOUT 10 TO ABOUT 30 PERCENT OF CALCIUM ORTHOPHOSPHATE CA3(PO4)2;
Claim 2
Dependent Claim
71 words
MELTING DOWN A MIXTURE ESSENTIALLY CONSISTING, IN WEIGHT PERCENT, OF ABOUT 20 TO BOUT 60 PERCENT OF SILICON DIOXIDE SIO2, ABOUT 2.7 TO ABOUT 20 PERCENT OF SODIUM OXIDE NA2O, ABOUT 0.4 TO ABOUT 20 PERCENT OF POTASSIUM OXIDE K2O, ABOUT 2.9 TO ABOUT 30 PERCENT OF MAGNESIUM OXIDE MGO, ABOUT 5 TO ABOUT 25 PERCENT OF CALCIUM OXIDE CAO, AND ABOUT 10 TO ABOUT 30 PERCENT OF CALCIUM ORTHOPHOSPHATE CA3(PO4)2;
Claim 3
Dependent Claim
14 words
IN A PROCESS OF PRODUCING A BIOCOMPATIBLE GLASS CERAMIC MATERIAL, THE STEPS WHICH COMPRISE
Claim 4
Dependent Claim
14 words
IN A PROCESS OF PRODUCING A BIOCOMPATIBLE GLASS CERAMIC MATERIAL, THE STEPS WHICH COMPRISE
Claim 5
Dependent Claim
14 words
cooling the resulting melt at least to the temperature of the following step; and
Claim 6
Dependent Claim
14 words
cooling the resulting melt at least to the temperature of the following step; and
Claim 7
Dependent Claim
27 words
The process of claim 1, in which the calcium orthophosphate in the starting glass component mixture is replaced by up to 25 percent of calcium metaphosphate Ca(PO3)2.
Claim 8
Dependent Claim
14 words
COOLING THE RESULTING MELT AT LEAST TO THE TEMPERATURE OF THE FOLLOWING STEP; AND
Claim 9
Dependent Claim
14 words
COOLING THE RESULTING MELT AT LEAST TO THE TEMPERATURE OF THE FOLLOWING STEP; AND
Claim 10
Dependent Claim
22 words
The process of claim 1, in which the starting glass component mixture additionally contains up to 5 percent of calcium fluoride CaF2.
Claim 11
Dependent Claim
126 words
subjecting the cooled melt to the following temperature-time ceramization program: a. Heating the resulting molten and cooled glass to the temperature (TKB) of optimum speed of crystal formation between about 550* C. and about 950* C. and maintaining said temperature (TKB) for between about 8 hours and about 30 hours; b. reducing the temperature of the mixture to a temperature (TO) between about 350*C. and about 550*C. and maintaining said temperature (TO) for between about 2 hours and about 5 hours; c. increasing the temperature of the mixture to the temperature (TKW) of optimum rate of crystal growth between about 700*C. and about 1,150*C. and mAintaining said temperature (TKW) for between about 10 hours and about 40 hours; and d. cooling the mixture to room temperature.
Claim 12
Dependent Claim
126 words
subjecting the cooled melt to the following temperature-time ceramization program: a. Heating the resulting molten and cooled glass to the temperature (TKB) of optimum speed of crystal formation between about 550* C. and about 950* C. and maintaining said temperature (TKB) for between about 8 hours and about 30 hours; b. reducing the temperature of the mixture to a temperature (TO) between about 350*C. and about 550*C. and maintaining said temperature (TO) for between about 2 hours and about 5 hours; c. increasing the temperature of the mixture to the temperature (TKW) of optimum rate of crystal growth between about 700*C. and about 1,150*C. and mAintaining said temperature (TKW) for between about 10 hours and about 40 hours; and d. cooling the mixture to room temperature.
Claim 13
Dependent Claim
124 words
SUBJECTING THE COOLED MELT TO THE FOLLOWING TEMPERATURETIME CERAMIZATION PROGRAM: A. HEATING THE RESULTING MOLTEN AND COOLED GLASS TO THE TEMPERATURE (TKB) OF OPTIMUM SPEED OF CRYSTAL FORMATION BETWEEN ABOUT 550*C. AND ABOUT 950*C. AND MAINTAINING SAID TEMPERATURE (TKB) FOR BETWEEN ABOUT 8 HOURS AND ABOUT 30 HOURS; B. REDUCING THE TEMPERATURE OF THE MIXTURE TO A TEMPERATURE (TO) BETWEEN ABOUT 350*C. AND ABOUT 550*C. AND MAINTAINING SAID TEMPERATURE (TO) FOR BETWEEN ABOUT 2 HOURS AND ABOUT 5 HOURS; C. INCREASING THE TEMPERATURE OF THE MIXTURE TO THE TEMPERATURE (TKW) OF OPTIMUM RATE OF CRYSTAL GROWTH BETWEEN ABOUT 700*C. AND ABOUT 1,150*C. AND MAINTAINING SAID TEMPERATURE (TKW) FOR BETWEEN ABOUT 10 HOURS AND ABOUT 40 HOURS; AND D. COOLING THE MIXTURE TO ROOM TEMPERATURE.
Claim 14
Dependent Claim
124 words
SUBJECTING THE COOLED MELT TO THE FOLLOWING TEMPERATURETIME CERAMIZATION PROGRAM: A. HEATING THE RESULTING MOLTEN AND COOLED GLASS TO THE TEMPERATURE (TKB) OF OPTIMUM SPEED OF CRYSTAL FORMATION BETWEEN ABOUT 550*C. AND ABOUT 950*C. AND MAINTAINING SAID TEMPERATURE (TKB) FOR BETWEEN ABOUT 8 HOURS AND ABOUT 30 HOURS; B. REDUCING THE TEMPERATURE OF THE MIXTURE TO A TEMPERATURE (TO) BETWEEN ABOUT 350*C. AND ABOUT 550*C. AND MAINTAINING SAID TEMPERATURE (TO) FOR BETWEEN ABOUT 2 HOURS AND ABOUT 5 HOURS; C. INCREASING THE TEMPERATURE OF THE MIXTURE TO THE TEMPERATURE (TKW) OF OPTIMUM RATE OF CRYSTAL GROWTH BETWEEN ABOUT 700*C. AND ABOUT 1,150*C. AND MAINTAINING SAID TEMPERATURE (TKW) FOR BETWEEN ABOUT 10 HOURS AND ABOUT 40 HOURS; AND D. COOLING THE MIXTURE TO ROOM TEMPERATURE.
Claim 15
Dependent Claim
22 words
The process of claim 2, in which the starting glass component mixture additionally contains up to 5 percent of calcium fluoride CaF2.
Claim 16
Dependent Claim
85 words
The process of claim 1, in which the starting glass component mixture essentially consists, in weight percent, of: between about 30 and about 60 percent of silicon dioxide SiO2, between about 3 and about 10 percent of sodium oxide Na2O, between about 3 and about 10 percent of potassium oxide K2O, between about 5 and about 20 percent of magnesium oxide MgO, between about 10 and about 20 percent of calcium oxide CaO, and between about 20 and about 30 percent of calcium orthophosphosphate Ca3(PO4)2.
Claim 17
Dependent Claim
30 words
The process of claim 5, in which the calcium orthophosphate in the starting glass component mixture is replaced by between about 10 and about 20 percent of calcium metaphosphate Ca(PO3)2.
Claim 18
Dependent Claim
67 words
The process of claim 1, in which the starting glass component mixture essentially consists, in weight percent, of 38.0 to 47.3 percent of silicon dioxide SiO2, 2.7 to 12.0 percent of sodium oxide Na2O, 0.4 to 6.8 percent of potassium oxide K2O, 2.9 to 16.5 percent of magnesium oxide MgO, 10.0 to 23.6 percent of calcium oxide CaO, and up to 25.5 percent of calcium orthophosphate Ca3(PO4)2.
Claim 19
Dependent Claim
21 words
The process of claim 7, in which the calcium orthophosphate is replaced by up to 18.4 percent of calcium metaphosphate Ca(PO3)2.
Claim 20
Dependent Claim
22 words
The process of claim 7, in which the starting glass component mixture additionally contains up to 4.0 percent of calcium fluoride CaF2.
Claim 21
Dependent Claim
22 words
The process of claim 8, in which the starting glass component mixture additionally contains up to 4.0 percent of calcium fluoride CaF2.
Claim 22
Dependent Claim
22 words
The process of claim 3, in which the calcium fluoride is at least partly replaced by a compound giving off fluorine ions.
Claim 23
Dependent Claim
22 words
The process of claim 4, in which the calcium fluoride is at least partly replaced by a compound giving off fluorine ions.
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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) | 1978-11-24 | 1979-05-26 | 1979-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-24 | 1983-05-26 | 1983-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-24 | 1987-05-26 | 1987-11-25 | $7700.00 | Window Closed / Lapsed |