US3975174A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manufacture of foam glass
Assignee: Saint Gobain Industries SA
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Filing: 1975-03-03
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Granted: 1976-08-17
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Expires: 1995-03-03
Abstract
Abstract Finely divided glass, which may have a viscosity between 10 6 and 10 7 poises at 950°C to 1100°C and which may be of a composition suitable to conversion into a vitroceramic, is mixed with up to a few percent by weight of a foaming agent including a mixture of SnO 2 and SiC, in equimolar proportions or with an excess of SiC. The resulting mixture is heated to 950°C to 1100°C to effect foaming by evolution of CO 2 from the foaming agent, and the resulting glass foam is cooled. The nucleation and crystallization steps by which the glass is converted to a vitroceramic may be caused to occur without allowing the foam to return to room temperature.
Inventors
- 👤 Pierre Camerlinck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 11:37
CPC Classifications
C; C03; C03C; C03C11/00; C03C11/007; C03B; C03B19/00; C03B19/08
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
92 words
A process for the manufacture of glass foam comprising admixing a finely divided glass having a viscosity between 10 6 and 10 7 poises at a temperature between 950°C. to 1100°C. with a foaming agent consisting essentially of stannic oxide and silicon carbide and heating said mixture to a temperature between 950°C. to 1100°C. for a time sufficient to cause said mixture to foam, said stannic oxide and said silicon carbide each being present in said foaming agent in an amount sufficient to generate sufficient carbon dioxide gas to foam said mixture.
Claim 2
Dependent Claim
92 words
A process for the manufacture of glass foam comprising admixing a finely divided glass having a viscosity between 10 6 and 10 7 poises at a temperature between 950°C. to 1100°C. with a foaming agent consisting essentially of stannic oxide and silicon carbide and heating said mixture to a temperature between 950°C. to 1100°C. for a time sufficient to cause said mixture to foam, said stannic oxide and said silicon carbide each being present in said foaming agent in an amount sufficient to generate sufficient carbon dioxide gas to foam said mixture.
Claim 3
Dependent Claim
23 words
A process according to claim 1 including the further step of pressing said mixture into a predetermined shape prior to said heating step.
Claim 4
Dependent Claim
38 words
A process according to claim 1 including the further step wherein the said stannic oxide and silicon carbide is first admixed and then mixed with the said glass to form the ultimate mixture prior to said heating step.
Claim 5
Dependent Claim
37 words
A process according to claim 3 wherein said admixture of stannic oxide and silicon carbide includes SnO 2 and SiC in a proportion of at least one mole of SiC to one mole of SnO 2 .
Claim 6
Dependent Claim
14 words
A process according to claim 3 in which said glass is a ceramifiable glass.
Claim 7
Dependent Claim
17 words
A process according to claim 5 wherein said glass includes in excess of 5% fluorine by weight.
Claim 8
Dependent Claim
21 words
A process according to claim 5 including the step of cooling the form directly to the crystallization temperature of the glass.
Claim 9
Dependent Claim
25 words
A process according to claim 1 in which the SnO 2 and SiC together have a weight not exceeding 3% by weight of the glass.
Claim 10
Dependent Claim
25 words
A process according to claim 1 in which the SnO 2 and SiC together have a weight of about 1.5% by weight of the glass.
Claim 11
Dependent Claim
44 words
A process according to claim 1 including the step of adding to the mixture prior to said heating step, an effective amount of finely divided Na 2 CO 3 not exceeding 2% by weight of the weight of the mixture as a fluxing agent.
Claim 12
Dependent Claim
103 words
A process for producing a glass foam composition consisting essentially of SiO 2 -Al 2 O 3 -CaO with minor portions of the oxides of magnesium, sodium, and potassium which process comprises the steps of forming a mixture of said glass composition and a foaming agent consisting essentially of stannic oxide and silicon carbide and heating said mixture to a temperature between 950°C. to 1100°C. for a time sufficient to cause said mixture to foam, said stannic oxide and said silicon carbide each being present in said foaming agent in an amount sufficient to generate sufficient carbon dioxide gas to foam said mixture.
Claim 13
Dependent Claim
103 words
A process for producing a glass foam composition consisting essentially of SiO 2 -Al 2 O 3 -CaO with minor portions of the oxides of magnesium, sodium, and potassium which process comprises the steps of forming a mixture of said glass composition and a foaming agent consisting essentially of stannic oxide and silicon carbide and heating said mixture to a temperature between 950°C. to 1100°C. for a time sufficient to cause said mixture to foam, said stannic oxide and said silicon carbide each being present in said foaming agent in an amount sufficient to generate sufficient carbon dioxide gas to foam said mixture.
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) | 1979-08-17 | 1980-02-16 | 1980-08-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-17 | 1984-02-16 | 1984-08-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-17 | 1988-02-16 | 1988-08-17 | $7700.00 | Window Closed / Lapsed |