Patent US5567490A successfully refreshed from Google Patents.
US5567490A
Expired / Lapsed
US
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White thermal control surfaces
Assignee: Lockheed Martin Corp
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Filing: 1995-06-02
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Granted: 1996-10-22
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Expires: 2015-06-02
Abstract
Abstract The present invention resides in a white thermal control surface resistant to darkening due to exposure to X-rays and ultraviolet radiation. The surface comprises a substrate and a ceramic zirconium orthosilicate coating on said substrate. The zirconium orthosilicate coating is obtained by plasma-spray applying particles of zirconium orthosilicate onto the substrate. The particles of zirconium orthosilicate are doped with an oxide of a +3 valent metal. The metal ions of said +3 valent metal oxide are dispersed substantially uniformly throughout said particles.
Inventors
- 👤 Harold A. Papazian
- 👤 Donald F. Shepard
- 👤 Edward A. Pierson
- 👤 Michael J. Gordon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 08:56
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/622; C04B35/62222; C04B35/01; C04B35/16; C23; C23C; C23C4/00; C23C4/04; C23C4/10; C23C4/11; Y; Y10; Y10T; Y10T428/00; Y10T428/13; Y10T428/131; Y10T428/1317; Y10T428/25; Y10T428/256; Y10T428/257; Y10T428/259
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
59 words
A method of preparing a white thermal control surface which is resistant to darkening due to exposure to X-rays and ultraviolet radiation comprising the steps of: (a) providing a substrate; and (b) plasma spray-applying onto said substrate particles of zirconium orthosilicate, said zirconium orthosilicate being doped with a dopant which is a metal oxide of a +3 valent metal.
Claim 2
Independent Claim
59 words
A method of preparing a white thermal control surface which is resistant to darkening due to exposure to X-rays and ultraviolet radiation comprising the steps of: (a) providing a substrate; and (b) plasma spray-applying onto said substrate particles of zirconium orthosilicate, said zirconium orthosilicate being doped with a dopant which is a metal oxide of a +3 valent metal.
Claim 3
Dependent Claim
30 words
The method of claim 1 wherein said dopant is added to the zirconium orthosilicate in the amount of about 1%-5% weight percent based on the weight of orthosilicate plus dopant.
Claim 4
Dependent Claim
25 words
The method of claim 2 wherein said particles are sintered particles classified to a particle size in the range of about 50 to 150 microns.
Claim 5
Dependent Claim
14 words
The method of claim 3 wherein said dopant is aluminum(III) oxide or lanthanum(III) oxide.
Claim 6
Dependent Claim
70 words
The method of claim 4 wherein said particles are prepared by the steps of: (a) forming a hydrosol of zirconium orthosilicate blended with of said dopant; (b) forming microspheres of said hydrosol; (c) allowing said microspheres to gel to form microspheres of hydrogel; (d) drying and sintering said hydrogel microspheres; (e) classifying said sintered microspheres to obtain sintered microspheres having a particle size in the range of about 50-150 microns.
Claim 7
Dependent Claim
15 words
A structure comprising a white thermal control surface prepared by the method of claim 1.
Claim 8
Dependent Claim
30 words
An enclosure for instruments or electronic equipment therein, which enclosure is sensitive to X-rays and ultraviolet radiation wherein said enclosure comprises a surface prepared by the method of claim 1.
Claim 9
Independent Claim
124 words
A method of preparing a ceramic, white, thermal control surface which is resistant to darkening due to exposure to X-rays and ultraviolet radiation, comprising the steps of: (a) providing a substrate; (b) forming a hydrosol of zirconium oxide and silicon dioxide in combination with about 1% to 5% by weight of a dopant which is a metal oxide of a +3 valent metal; (c) forming microspheres of said hydrosol; (d) allowing said hydrosol microspheres to gel to form hydrogel microspheres; (e) sintering said hydrogel microspheres; (f) classifying said sintered hydrogel microspheres to obtain a sintered microsphere product having a particle size in the range of 50-150 microns; and (g) plasma spray applying said sintered microspheres onto said substrate to prepare said thermal control surface.
Claim 10
Independent Claim
124 words
A method of preparing a ceramic, white, thermal control surface which is resistant to darkening due to exposure to X-rays and ultraviolet radiation, comprising the steps of: (a) providing a substrate; (b) forming a hydrosol of zirconium oxide and silicon dioxide in combination with about 1% to 5% by weight of a dopant which is a metal oxide of a +3 valent metal; (c) forming microspheres of said hydrosol; (d) allowing said hydrosol microspheres to gel to form hydrogel microspheres; (e) sintering said hydrogel microspheres; (f) classifying said sintered hydrogel microspheres to obtain a sintered microsphere product having a particle size in the range of 50-150 microns; and (g) plasma spray applying said sintered microspheres onto said substrate to prepare said thermal control surface.
Claim 11
Dependent Claim
15 words
A structure comprising a white thermal control surface prepared by the method of claim 8.
Claim 12
Dependent Claim
30 words
An enclosure for instruments or electronic equipment therein, which enclosure is sensitive to X-rays and ultraviolet radiation wherein said enclosure comprises a surface prepared by the method of claim 8.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-10-22 | 2000-04-22 | 2000-10-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-10-22 | 2004-04-22 | 2004-10-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-10-22 | 2008-04-22 | 2008-10-22 | $7700.00 | Window Closed / Lapsed |