Patent US3599029A successfully refreshed from Google Patents.
US3599029A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluorescent lamp envelope with transparent protective coating
Assignee: General Electric Co
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Filing: 1969-10-31
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Granted: 1971-08-10
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Expires: 1989-10-31
Abstract
Abstract A fluorescent lamp having on the inner surface of its envelope a transparent protective coating consisting of a layer of titanium dioxide adherent to the glass and a layer of aluminum oxide thereover. The coating is prepared by flushing through the glass envelope or tube a mixture comprising a solution of tetrabutyl titanate in a thinner and a dispersion of aluminum oxide in an organic binder, and then drying. The phosphor coating is applied over the protective coating in conventional manner using a water soluble binder system and other manufacturing steps are unchanged. Advantages are higher lumens, improved maintenance particularly in highly loaded lamps, elimination of oxide rings, and avoidance of darkening where the phosphor coating is thin.
Inventors
- 👤 William C Martyny
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 10:02
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/02; C09K11/025; H; H01; H01J; H01J61/00; H01J61/02; H01J61/30; H01J61/35; H01J61/38; H01J61/42; H01J61/46
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
92 words
A low pressure discharge lamp comprising a sealed elongated glass envelope having electrodes sealed therein at opposite ends, said envelope enclosing a charge of mercury and an inert ionizable starting gas, and a composite protective barrier coating adhering to the inner surface of said envelope, said coating comprising a layer consisting essentially of titanium dioxide having a thickness from 0.002 to 0.02 microns coated on and adhering to the inner surface of said envelope and a layer consisting essentially of aluminum oxide 1 to 10 microns thick over said titanium dioxide layer.
Claim 2
Dependent Claim
92 words
A low pressure discharge lamp comprising a sealed elongated glass envelope having electrodes sealed therein at opposite ends, said envelope enclosing a charge of mercury and an inert ionizable starting gas, and a composite protective barrier coating adhering to the inner surface of said envelope, said coating comprising a layer consisting essentially of titanium dioxide having a thickness from 0.002 to 0.02 microns coated on and adhering to the inner surface of said envelope and a layer consisting essentially of aluminum oxide 1 to 10 microns thick over said titanium dioxide layer.
Claim 3
Dependent Claim
30 words
A lamp as in claim 1 wherein the titanium dioxide layer is from 0.005 to 0.01 microns thick and the aluminum oxide layer is from 2 to 5 microns thick.
Claim 4
Dependent Claim
21 words
A lamp as in claim 1 which is a fluorescent lamp and comprises a phosphor coating over the protective barrier coating.
Claim 5
Dependent Claim
70 words
A component for a low pressure discharge lamp envelope comprising a glass tube having a composite protective coating adhering to its inner surface, said coating comprising a layer consisting essentially of titanium dioxide having a thickness from 0.002 to 0.02 microns coated on and adhering to the inner surface of said tube and a layer consisting essentially of aluminum oxide 1 to 10 microns thick over said titanium dioxide layer.
Claim 6
Dependent Claim
70 words
A component for a low pressure discharge lamp envelope comprising a glass tube having a composite protective coating adhering to its inner surface, said coating comprising a layer consisting essentially of titanium dioxide having a thickness from 0.002 to 0.02 microns coated on and adhering to the inner surface of said tube and a layer consisting essentially of aluminum oxide 1 to 10 microns thick over said titanium dioxide layer.
Claim 7
Dependent Claim
30 words
A component as in claim 4 wherein the titanium dioxide layer is from 0.005 to 0.01 microns thick and the aluminum oxide layer is from 2 to 5 microns thick.
Claim 8
Dependent Claim
15 words
A component as in claim 4 having a phosphor coating over the protective barrier coating.
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) | 1974-08-09 | 1975-02-08 | 1975-08-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-09 | 1979-02-08 | 1979-08-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-09 | 1983-02-08 | 1983-08-10 | $7700.00 | Window Closed / Lapsed |