US4328022A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Composite article and method of sealing
Assignee: Corning Glass Works
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Filing: 1980-06-23
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Granted: 1982-05-04
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Expires: 2000-06-23
Abstract
Abstract A composite article is disclosed which embodies a thermally sensitive component enclosed within borosilicate glass bodies having a coefficient of thermal expansion in the range of 30 to 40×10 -7 /°C. The bodies are joined by an intermediate layer of sealing material which is a fused mixture of a sealing glass containing an infra-red absorbing oxide and a mill additive having a low coefficient of thermal expansion. There is further disclosed a method of forming the seal between the glass bodies by application of infra-red radiation to the sealing material.
Inventors
- 👤 John A. Bonk
- 👤 Joseph W. Malmendier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:07
CPC Classifications
H; H01; H01J; H01J5/00; H01J5/20; H01J5/22; H01J5/24; C; C03; C03C; C03C8/00; C03C8/24
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
240 words
A method of producing a composite article in which two glass bodies are hermetically joined along opposed sealing surfaces by an intermediate layer of a sealing material, each glass body being molded from a borosilicate glass having a coefficient of thermal expansion in the range of 30 to 40×10 -7 /°C., the method comprising the following steps: forming a sealing mixture composed of a sealing glass and a mill addition, the sealing glass having a softening point below 700° C., a coefficient of thermal expansion greater than that of the borosilicate glass parts, and being a zinc silicoborate consisting essentially, expressed in weight percent on the oxide basis, of 60-70% ZnO, 10-16% SiO 2 , and 19-25% B 2 O 3 , and containing in its composition 1-20% by weight of an infra-red absorbing oxide selected from copper oxide, iron oxide, and mixtures of such oxides, and the mill addition, as compared to the sealing glass, having a substantially higher softening point, a lower coefficient of thermal expansion, and being a glass having the approximate composition of the mineral cordierite; applying a strip-like layer of such sealing material to the sealing surface of at least one part; assembling the glass bodies in contacting relation through the sealing material; and focusing infra-red radiation sources through the walls of the parts onto opposite sides of the sealing material to soften the sealing glass and form a hermetic seal between the glass bodies.
Claim 2
Independent Claim
240 words
A method of producing a composite article in which two glass bodies are hermetically joined along opposed sealing surfaces by an intermediate layer of a sealing material, each glass body being molded from a borosilicate glass having a coefficient of thermal expansion in the range of 30 to 40×10 -7 /°C., the method comprising the following steps: forming a sealing mixture composed of a sealing glass and a mill addition, the sealing glass having a softening point below 700° C., a coefficient of thermal expansion greater than that of the borosilicate glass parts, and being a zinc silicoborate consisting essentially, expressed in weight percent on the oxide basis, of 60-70% ZnO, 10-16% SiO 2 , and 19-25% B 2 O 3 , and containing in its composition 1-20% by weight of an infra-red absorbing oxide selected from copper oxide, iron oxide, and mixtures of such oxides, and the mill addition, as compared to the sealing glass, having a substantially higher softening point, a lower coefficient of thermal expansion, and being a glass having the approximate composition of the mineral cordierite; applying a strip-like layer of such sealing material to the sealing surface of at least one part; assembling the glass bodies in contacting relation through the sealing material; and focusing infra-red radiation sources through the walls of the parts onto opposite sides of the sealing material to soften the sealing glass and form a hermetic seal between the glass bodies.
Claim 3
Dependent Claim
30 words
A method in accordance with claim 1 in which the assembly is preheated to a temperature not over about 500° C. prior to applying infra-red heat to the sealing zone.
Claim 4
Dependent Claim
48 words
A method according to claim 1 wherein said focused infra-red radiation is directed from two separate sources set at an angle on the order of 60°-90° with respect to each other so that radiation is focused at both the upper and lower surfaces of the sealing glass layer.
Claim 5
Dependent Claim
21 words
A method according to claim 1 wherein said mill addition does not exceed about 20% by weight of said sealing material.
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) | 1985-05-03 | 1985-11-02 | 1986-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-05-03 | 1989-11-02 | 1990-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-05-03 | 1993-11-02 | 1994-05-04 | $7700.00 | Window Closed / Lapsed |