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Electrostatic coating of silica powders on incandescent bulbs

Assignee: General Electric Co
•
Filing: 1975-11-20
•
Granted: 1978-03-28
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Expires: 1995-11-20
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Abstract

Abstract An improved electrostatically deposited coating is obtained by controlling the particle size and resistivity of the silica powder.

Inventors

  • 👤 Clifford B. Collins
  • 👤 William G. James

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 13:58
CPC Classifications
H; H01; H01K; H01K3/00; H01K3/005; C; C03; C03C; C03C17/00; C03C17/22; C03C17/23; H01K1/00; H01K1/28; H01K1/32; C03C2217/00; C03C2217/20; C03C2217/21; C03C2217/213; C03C2217/29; C03C2218/00; C03C2218/10; C03C2218/17

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 42 words
An electric lamp comprising a bulb having a light-diffusing coating on the inside thereof comprising an electrostatically deposited powder comprising light refractive particles having a particle size of 1 to 4 microns and a resistivity of 10 8 to 10 11 ohm-centimeters.
Claim 2
Dependent Claim 42 words
An electric lamp comprising a bulb having a light-diffusing coating on the inside thereof comprising an electrostatically deposited powder comprising light refractive particles having a particle size of 1 to 4 microns and a resistivity of 10 8 to 10 11 ohm-centimeters.
Claim 3
Dependent Claim 15 words
The bulb as set forth in claim 1 wherein said powder consists essentially of silica.
Claim 4
Dependent Claim 32 words
A powder for electrostatically coating an electric lamp comprising light refractive particles having: a particle size of from 1 to 4 microns, and a resistivity of 10 8 to 10 11 ohm-centimeters.
Claim 5
Dependent Claim 32 words
A powder for electrostatically coating an electric lamp comprising light refractive particles having: a particle size of from 1 to 4 microns, and a resistivity of 10 8 to 10 11 ohm-centimeters.
Claim 6
Dependent Claim 15 words
The powder as set forth in claim 3 wherein said powder consists essentially of silica.
Claim 7
Dependent Claim 30 words
The powder as set forth in claim 4 comprising a mixture of powders of different resistivities wherein the mixture has a resistivity of from 10 8 to 10 11 ohm-centimeters.
Claim 8
Dependent Claim 30 words
The powder mixture as set forth in claim 5 wherein at least one of said powders has a resistivity outside of the range of 10 8 to 10 11 ohm-centimeters.
Claim 9
Dependent Claim 26 words
The powder as set forth in claim 4 and further comprising up to 1.8% by weight resistivity reducing material for reducing the resistivity of the powder.
Claim 10
Dependent Claim 17 words
The powder as set forth in claim 7 wherein said resistivity reducing material comprises a sodium compound.
Claim 11
Dependent Claim 15 words
The powder as set forth in claim 8 wherein said sodium compound comprises sodium chloride.
Claim 12
Dependent Claim 18 words
The powder as set forth in claim 4 having a resistivity of 10 8 to 10 10 ohm-centimeters.
Claim 13
Dependent Claim 18 words
The powder as set forth in claim 4 having a resistivity of 10 9 to 10 11 ohm-centimeters.
Claim 14
Dependent Claim 30 words
The powder as set forth in claim 3 wherein said powder consists essentially of a material selected from the group consisting of: alumina, silica, aluminosilica, calcium carbonate, and mixtures thereof.

References Cited (Backward Citations)

US2661438A Cited
US2806444A Cited
US2922065A Cited
US2878136A Cited
US3126300A Cited
US3320460A Cited
US3909649A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-03-27 1981-09-26 1982-03-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-03-27 1985-09-26 1986-03-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-03-27 1989-09-26 1990-03-28 $7700.00 Window Closed / Lapsed

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