US4000346A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optically transparent, electrically conductive coating
Assignee: Praxair ST Technology Inc
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Filing: 1975-07-07
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Granted: 1976-12-28
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Expires: 1995-07-07
Abstract
Abstract An electrically conductive and optically transparent coating comprising a very thin, noble metal oxide film applied to a nonconductive, transparent substrate, said noble metal selected from the group consisting of ruthenium, rhodium, osmium and iridium. These coatings are useful as resistance heaters for windows, as optically transparent electrodes for electro-optic and electro-chemical applications, for radio frequency shieldings and a wide variety of other applications.
Inventors
- 👤 Michael Brendan Dowell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 10:08
CPC Classifications
H; H05; H05B; H05B3/00; H05B3/84; C; C03; C03C; C03C17/00; C03C17/22; C03C17/23; C03C17/25; H01; H01B; H01B1/00; C03C2217/00; C03C2217/20; C03C2217/21; C03C2217/228; C03C2218/00; C03C2218/10; C03C2218/11; H05B2203/00; H05B2203/017; Y; Y10; Y10T; Y10T428/00; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/265
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
122 words
A process for applying a coating to a surface of a substrate comprising the following steps: a. depositing a solution onto an electrically nonconducting and optically transparent substrate, said solution comprising a noble metal salt, said noble metal selected from the group consisting of ruthenium, rhodium, osmium and iridium; and b. evaporating said solution at a temperature sufficient to leave a residue of said salt; and c. heating said residue at a predetermined temperature for a time period sufficient to convert said deposit into a coating of predetermined thickness between about 0.2 μm and about 2 μm on said substrate, said coating comprising a noble oxide film having an electrical resistance no greater than about 700 ohms per square and optical transparency.
Claim 2
Dependent Claim
122 words
A process for applying a coating to a surface of a substrate comprising the following steps: a. depositing a solution onto an electrically nonconducting and optically transparent substrate, said solution comprising a noble metal salt, said noble metal selected from the group consisting of ruthenium, rhodium, osmium and iridium; and b. evaporating said solution at a temperature sufficient to leave a residue of said salt; and c. heating said residue at a predetermined temperature for a time period sufficient to convert said deposit into a coating of predetermined thickness between about 0.2 μm and about 2 μm on said substrate, said coating comprising a noble oxide film having an electrical resistance no greater than about 700 ohms per square and optical transparency.
Claim 3
Dependent Claim
20 words
A process as defined in claim 1 wherein said electrical resistance is no greater than about 500 ohms per square.
Claim 4
Dependent Claim
17 words
A process as defined in claim 1 wherein in step (a) said solution also includes a solvent.
Claim 5
Dependent Claim
27 words
A process as defined in claim 3 wherein said salt is a member selected from the group consisting of a halide, an acetate, a nitrate and resinate.
Claim 6
Dependent Claim
37 words
A process as defined in claim 4 wherein step (a) said solvent is a normally liquid solvent selected from the group consisting of an aqueous inorganic acid solution, a halogenated hydrocarbon, an alcohol and a heterocyclic composition.
Claim 7
Dependent Claim
24 words
A process as defined in claim 5 wherein in step (a) said salt is a nitrate and said solvent is an aqueous inorganic solution.
Claim 8
Dependent Claim
22 words
A process as defined in claim 5 wherein in step (a) said salt is a halide and said solvent is an alcohol.
Claim 9
Dependent Claim
22 words
A process as defined in claim 5 wherein in step (a) said salt is an acetate and said solvent is an alcohol.
Claim 10
Dependent Claim
21 words
A process as defined in claim 5 wherein in step (a) said salt is a resinate and said solvent is linalool.
Claim 11
Dependent Claim
51 words
A process as defined in claim 1 wherein in step (b), said temperature is between about 60° C. and about 160° C; and in step (c), said predetermined temperature is between about 350° C. and about 700° C. and said time period is between about two minutes and about 20 minutes.
Claim 12
Dependent Claim
24 words
A process as defined in claim 1 wherein said optical transparency is present at a wavelength between about 1900 A and about 40,000 A.
Claim 13
Dependent Claim
14 words
A process as defined in claim 11 wherein said wavelength is about 10,600 A.
Claim 14
Dependent Claim
28 words
A process as defined in claim 1 wherein said substrate is a member selected from the group consisting of quartz, alumina, fused silica, magnesia, glass and Pyrex glass.
Claim 15
Dependent Claim
41 words
A process as defined in claim 1 wherein in step (a) said solution further includes up to about 38 percent by weight of a member selected from the group consisting of a valve metal organometallic compound and a valve metal salt.
Claim 16
Dependent Claim
41 words
A process as defined in claim 1 wherein in step (a) said solution contains an equimolar mixture of a noble metal salt and a valve metal salt; said noble metal selected from the group consisting of ruthenium, rhodium, osmium and iridium.
Claim 17
Dependent Claim
25 words
A process as defined in claim 15 wherein said noble metal salt is a ruthenium resinate and said valve metal salt is a tin resinate.
Claim 18
Dependent Claim
108 words
A conductive, optically transparent composite comprising at least a first layer of an electrically conductive, optically transparent coating and a second layer of a nonconducting, optically transparent substrate, said first layer bonded to and covering at least one surface of said second layer; said first layer composed of a noble metal oxide film and characterized by an electrical resistance no greater than about 700 ohms per square and a thickness between about 0.2 μm and about 2 μm such that light transmission through said coating is not reduced to less than about 10 percent, said noble metal selected from the group consisting of ruthenium, rhodium, osmium and iridium.
Claim 19
Dependent Claim
108 words
A conductive, optically transparent composite comprising at least a first layer of an electrically conductive, optically transparent coating and a second layer of a nonconducting, optically transparent substrate, said first layer bonded to and covering at least one surface of said second layer; said first layer composed of a noble metal oxide film and characterized by an electrical resistance no greater than about 700 ohms per square and a thickness between about 0.2 μm and about 2 μm such that light transmission through said coating is not reduced to less than about 10 percent, said noble metal selected from the group consisting of ruthenium, rhodium, osmium and iridium.
Claim 20
Dependent Claim
28 words
A composite as defined in claim 17 wherein said substrate is a member selected from the group consisting of quartz, alumina, fused silica, magnesia, glass and Pyrex glass.
Claim 21
Dependent Claim
22 words
A composite as defined in claim 17 which is optically transparent at a wavelength between about 1900 A and about 40,000 A.
Claim 22
Dependent Claim
14 words
A composite as defined in claim 19 wherein said wavelength is about 10,600 A.
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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) | 1979-12-28 | 1980-06-28 | 1980-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-12-28 | 1984-06-28 | 1984-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-12-28 | 1988-06-28 | 1988-12-28 | $7700.00 | Window Closed / Lapsed |