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US3581137A Expired / Lapsed US ⏱️ 0.0 years remaining

Electric lamp having an envelope composed of photoresistant soda-lime silicate glass

Assignee: Philips North America LLC
•
Filing: 1968-07-15
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Granted: 1971-05-25
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Expires: 1988-07-15
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Abstract

Abstract The light output and lumen maintenance of an electric lamp that generates both visible and ultraviolet radiations (e.g., a fluorescent, an incandescent, or a high-pressure mercury vapor discharge lamp) is enhanced by utilizing an envelope that is composed of a modified soda-lime silicate glass which has a low initial coefficient of absorption in the visible region (below about 0.05 cm. 1), and inhibits the discoloration or ''''solarization'''' effect of impinging ultraviolet-radiation. The absorption coefficient in the visible region is maintained below approximately 0.4 cm. 1 after prolonged exposure of the envelope to ultraviolet radiation by controlling the Fe203 content and adding selected amounts of Ti02 or Mo03, or mixtures thereof, to the glass during manufacture. The preferred ranges are between 0.8 percent and about 3 percent by weight Ti02 and from about 0.5 percent to 1 percent by weight Mo03 when these materials are added as separate components. The Fe203 content does not exceed about 0.07 percent by weight.

Inventors

  • 👤 Edward G F Arnott
  • 👤 Daniel W Lewis

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 00:01
CPC Classifications
C; C03; C03C; C03C3/00; C03C3/04; C03C3/076; C03C3/083; C03C3/085; C03C3/087; C03C4/00; C03C4/08; C03C4/085; H; H01; H01J; H01J5/00; H01J5/02; H01J5/04; H01J61/00; H01J61/02; H01J61/38; H01J61/40; H01K; H01K1/00; H01K1/28; H01K1/32; Y; Y10; Y10S; Y10S501/00; Y10S501/90; Y10S501/905

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 45 words
The combination set forth in claim 1 wherein; said ultraviolet-radiation absorbing material comprises between about 0.8 percent and about 10 percent by weight Ti02, and said glass also contains an additional ultraviolet-radiation absorbing material consisting of from 0.01 percent to 2 percent by weight As203.
Claim 2
Dependent Claim 37 words
The combination set forth in claim 1 wherein; said ultraviolet-radiation absorbing material comprises from about 0.5 percent to 1 percent by weight Mo03, and said glass also contains from 0.01 percent to 2 percent by weight As203.
Claim 3
Dependent Claim 39 words
The combination set forth in claim 1 wherein; said ultraviolet-radiation absorbing material comprises between 0.8 percent and 3 percent by weight Ti02, and the Fe203 coNtent of the glass is between about 0.05 percent and 0.07 percent by weight.
Claim 4
Dependent Claim 24 words
The combination set forth in claim 1 wherein said glass contains about 0.05 percent by weight Fe203 and about 1.5 percent by weight Ti02.
Claim 5
Dependent Claim 41 words
The combination set forth in claim 1 wherein; said lamp comprises a fluorescent lamp, and said envelope is of tubular configuration and interiorly coated with a phosphor that is responsive to ultraviolet-radiation and is adversely affected by sodium or sodium ions.
Claim 6
Dependent Claim 15 words
The combination set forth in claim 6 wherein said phosphor is of the halophosphate type.
Claim 7
Dependent Claim 18 words
The combination set forth in claim 7 wherein said phosphor is calcium halophosphate activated by antimony and manganese.
Claim 8
Dependent Claim 31 words
The combination set forth in claim 1 wherein; said lamp comprises a high-pressure mercury vapor discharge lamp, and said radiation-generating means comprises an arc tube that is disposed within said envelope.
Claim 9
Dependent Claim 20 words
The combination of claim 9 wherein the inner surface of said envelope is coated with a layer of ultraviolet-responsive phosphor.
Claim 10
Dependent Claim 14 words
The combination set forth in claim 1 wherein said lamp comprises an incandescent lamp.
Claim 11
Dependent Claim 14 words
The combination set forth in claim 1 wherein said glass has the following composition:
Claim 12
Dependent Claim 14 words
The combination set forth in claim 1 wherein said glass has the following composition:
Claim 13
Dependent Claim 31 words
The combination set forth in claim 4 wherein said glass also contains from 0.01 percent to 2 by weight of a material selected from the group consisting of Sb203 and As203.
Claim 14
Dependent Claim 25 words
The combination of claim 4 wherein said glass contains about 0.05 percent by weight Fe203 and from 0.01 percent to 2 percent by weight Sb203.
Claim 15
Dependent Claim 79 words
The combination set forth in claim 1 wherein; said ultraviolet-radiation absorbing material comprises from about 0.5 percent to 1 percent by weight Mo03, the Fe203 content of the glass is between about 0.05 percent and 0.07 percent by weight, and the amounts of the Fe203 and Mo03 constituents are sufficient to maintain the absorption coefficient of the glass at 4800 A and 5800 below approximately 0.4 cm. 1 during a major portion of the useful life of the lamp.

References Cited (Backward Citations)

US1292147A Cited
DE543095C Cited
US1830902A Cited
US3148300A Cited
US3146120A Cited
US3253174A Cited
US3377494A Cited
US3430089A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1974-05-24 1974-11-23 1975-05-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1978-05-24 1978-11-23 1979-05-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1982-05-24 1982-11-23 1983-05-25 $7700.00 Window Closed / Lapsed

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