US4012655A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Refractory metal oxide reflector coating on lamp envelope
Assignee: General Electric Co
•
Filing: 1975-08-04
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Granted: 1977-03-15
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Expires: 1995-08-04
Abstract
Abstract The adherence of an optically reflective coating of refractory metal oxide particles such as ZrO 2 or Al 2 O 3 on a fused silica discharge tube surface is improved severalfold by an adhesion layer consisting of colloidal aluminum oxide and boric oxide powders. The adhesion layer may be first applied and dried, the refractory metal oxide coating then applied, and the quartz tube then heated to a temperature greater than 460° C., the melting point of boric oxide. The refractory metal oxide particles may also be applied admixed with the colloidal aluminum oxide and the boric oxide. The improved coating strength permits the use of a thicker layer of refractory metal oxide for higher optical and thermal reflection.
Inventors
- 👤 Charles I. McVey
- 👤 O. Manuel Uy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:46
CPC Classifications
H; H01; H01J; H01J9/00; H01J9/20; H01J61/00; H01J61/02; H01J61/30; H01J61/35
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
48 words
A fused silica envelope having an optically reflective coating of Al 2 O 3 particles adherent thereto by means of an adhesion layer consisting of colloidal aluminum oxide and boric oxide heat-reacted with the silica surface, said Al 2 O 3 particles being heat-reacted with said adhesion layer.
Claim 2
Dependent Claim
48 words
A fused silica envelope having an optically reflective coating of Al 2 O 3 particles adherent thereto by means of an adhesion layer consisting of colloidal aluminum oxide and boric oxide heat-reacted with the silica surface, said Al 2 O 3 particles being heat-reacted with said adhesion layer.
Claim 3
Dependent Claim
33 words
A fused silica envelope as in claim 1 wherein the colloidal aluminum oxide and boric oxide are present primarily in a layer intermediate the silica surface and the Al 2 O 3 particles.
Claim 4
Dependent Claim
25 words
A fused silica envelope as in claim 1 wherein the colloidal aluminum oxide and boric oxide are dispersed between the Al 2 O 3 particles.
Claim 5
Dependent Claim
39 words
A fused silica envelope as in claim 1 wherein the colloidal aluminum oxide and boric oxide are present in a layer intermediate the silica surface and the Al 2 O 3 particles, and also are dispersed between the particles.
Claim 6
Dependent Claim
44 words
A fused silica envelope as in claim 1 wherein the weight of B 2 O 3 in said adhesion layer is from 0.05 to 0.5 mg/cm 2 and the weight of colloidal Al 2 O 3 is from 0.05 to 1.5 mg/cm 2 .
Claim 7
Dependent Claim
28 words
A fused silica envelope as in claim 2 wherein the weight of Al 2 O 3 particles in said coating is from 5 to 30 mg/cm 2 .
Claim 8
Dependent Claim
59 words
A fused silica envelope as in claim 1 wherein the weight of B 2 O 3 in said adhesion layer is about 0.1 mg/cm 2 and that of colloidal Al 2 O 3 is about 0.3 mg/cm 2 , and the weight of Al 2 O 3 particles in said coating is from 5 to 30 mg/cm 2 .
Claim 9
Dependent Claim
57 words
A fused silica envelope having an optically reflective coating of ZrO 2 particles adherent thereto by means of an adhesion layer consisting of colloidal aluminum oxide and boric oxide heat-reacted with the silica surface, said ZrO 2 particles being heat-reacted with said adhesion layer, the aluminum oxide and boric oxide being dispersed between the ZrO 2 particles.
Claim 10
Dependent Claim
57 words
A fused silica envelope having an optically reflective coating of ZrO 2 particles adherent thereto by means of an adhesion layer consisting of colloidal aluminum oxide and boric oxide heat-reacted with the silica surface, said ZrO 2 particles being heat-reacted with said adhesion layer, the aluminum oxide and boric oxide being dispersed between the ZrO 2 particles.
Claim 11
Dependent Claim
30 words
A fused silica envelope as in claim 8 wherein the aluminum oxide and boric oxide are also present in a layer intermediate the silica surface and the ZrO 2 particles.
Claim 12
Dependent Claim
38 words
An alumina ceramic envelope having an optically reflective coating of refractory metal oxide particles adherent thereby by means of an adhesion layer consisting of colloidal aluminum oxide and boric oxide heat-reacted with the particles and the alumina surface.
Claim 13
Dependent Claim
38 words
An alumina ceramic envelope having an optically reflective coating of refractory metal oxide particles adherent thereby by means of an adhesion layer consisting of colloidal aluminum oxide and boric oxide heat-reacted with the particles and the alumina surface.
References Cited (Backward Citations)
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US3533827A
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US3374377A
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US3851200A
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US3879625A
Cited
US3889142A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-03-14 | 1980-09-13 | 1981-03-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-03-14 | 1984-09-13 | 1985-03-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-03-14 | 1988-09-13 | 1989-03-15 | $7700.00 | Window Closed / Lapsed |