US4004052A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing non-porous coating for corundum substrates
Assignee: Individual
•
Filing: 1975-12-01
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Granted: 1977-01-18
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Expires: 1995-12-01
Abstract
Abstract A process for producing a non-porous coating for corundum substrates with a corundum content of 90 to 100% the process comprises applying a barium, calcium or strontium alumosilicate glaze to the substrate, followed by heat treatment of the substrate at a temperature within a range of from 1,350 to 1,650°C at a heating rate of from 100° to 500° C per hour, and thereafter cooling at a rate of about 150° C per hour, thus giving a glass-ceramic coating on the substrate. The process is useful, mainly, for producing integral circuits and other micro-circuits and precision resistors.
Inventors
- 👤 Vera Ivanovna Bystrova
- 👤 Galina Konstantinovna Kirillova
- 👤 Galina Atkhipovna Mikhailova
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:37
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/45; C04B41/50; C04B41/5022; C04B41/80; C04B41/81; C04B41/85; C04B41/86; H; H01; H01C; H01C17/00; H01C17/06; H01C17/065; H01C17/06506; H01C17/06573; H01C17/0658; H10; H10W; H10W70/00; H10W70/60; H10W70/67; H10W70/69; H10W70/692; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31536
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
99 words
A process for producing a non-porous coating for corundum substrates having a corundum content of 90 to 100%, comprising applying a barium, calcium or strontium alumosilicate glaze layer onto said corundum substrate and heat treating the same at a temperature within the range of from 1,350° to 1,650° C at a heating rate of from 100° to 500° C per hour, and thereafter cooling at a rate of about 150° C per hour, whereby corundum from the surface layer of said substrate reacts with said glaze thus forming a barium, calcium or strontium feldspar glass-ceramic coating on the substrate.
Claim 2
Dependent Claim
99 words
A process for producing a non-porous coating for corundum substrates having a corundum content of 90 to 100%, comprising applying a barium, calcium or strontium alumosilicate glaze layer onto said corundum substrate and heat treating the same at a temperature within the range of from 1,350° to 1,650° C at a heating rate of from 100° to 500° C per hour, and thereafter cooling at a rate of about 150° C per hour, whereby corundum from the surface layer of said substrate reacts with said glaze thus forming a barium, calcium or strontium feldspar glass-ceramic coating on the substrate.
References Cited (Backward Citations)
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US3384508A
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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) | 1980-01-18 | 1980-07-19 | 1981-01-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-01-18 | 1984-07-19 | 1985-01-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-01-18 | 1988-07-19 | 1989-01-18 | $7700.00 | Window Closed / Lapsed |