Patent US4904526A successfully refreshed from Google Patents.
US4904526A
Expired / Lapsed
US
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Electrically conductive metal oxide coatings
Assignee: 3M Co
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Filing: 1988-08-29
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Granted: 1990-02-27
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Expires: 2008-08-29
Abstract
Abstract A method for forming a metal oxide film on a substrate is provided comprising the steps of depositing a continuous metal layer having an exposed surface onto a substrate, forming a metal oxide layer on the exposed surface, contacting the oxide layer with an effective amount of a fluxing agent, providing a protective polymeric layer on the oxide layer and forming discrete metal microspheres by melting the metal layer. A metal polymer composite comprising a continuous metal oxide layer which may be transparent is thus provided.
Inventors
- 👤 David C. Koskenmaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 14:28
CPC Classifications
H; H01; H01B; H01B1/00; H01B1/06; H01B1/08; H10; H10F; H10F71/00; H10F71/138; H10F77/00; H10F77/20; H10F77/244; Y; Y02; Y02E; Y02E10/00; Y02E10/50; Y10; Y10T; Y10T428/00; Y10T428/25; Y10T428/256; Y10T428/29; Y10T428/2982
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
76 words
A method for forming a metal oxide film on a substrate comprising the steps of: (a) depositing a continuous metal layer onto a substrate, said layer of metal having an exposed surface; (b) forming a metal oxide layer on said exposed surface; (c) contacting said oxide layer with an effective amount of a fluxing agent; (d) providing a protective polymer layer on said oxide layer; and (e) forming discrete metal microspheres by melting said metal layer.
Claim 2
Independent Claim
76 words
A method for forming a metal oxide film on a substrate comprising the steps of: (a) depositing a continuous metal layer onto a substrate, said layer of metal having an exposed surface; (b) forming a metal oxide layer on said exposed surface; (c) contacting said oxide layer with an effective amount of a fluxing agent; (d) providing a protective polymer layer on said oxide layer; and (e) forming discrete metal microspheres by melting said metal layer.
Claim 3
Dependent Claim
29 words
The method of claim 1 wherein said metal layer is deposited on said substrate by forming a vapor in a vacuum chamber and depositing by means of vacuum deposition.
Claim 4
Dependent Claim
36 words
The method of claim 1 wherein said metal layer comprises a metal selected from the group consisting of indium, indium-tin, tin, cadmium, cadmium-tin, mixtures thereof, and such metals, alloys and mixtures doped with antimony or flourine.
Claim 5
Dependent Claim
32 words
The method of claim 3 wherein said metal is selected from the group consisting of substantially pure indium and an indium-tin alloy having between about 5 and about 25% tin by weight.
Claim 6
Dependent Claim
14 words
The method of claim 2 wherein said vapor is formed by evaporating said metal.
Claim 7
Dependent Claim
15 words
The method of claim 5 wherein said metal is evaporated by means of electron-beam evaporation.
Claim 8
Dependent Claim
21 words
The method of claim 1 wherein said oxide layer is formed by heating said metal layer in the presence of oxygen.
Claim 9
Dependent Claim
18 words
The method of claim 1 wherein said oxide layer has a resistance of less than about 5000 ohms/square.
Claim 10
Dependent Claim
20 words
The method of claim 8 wherein said oxide layer has a thickness of between about 50 and about 100 angstroms.
Claim 11
Dependent Claim
13 words
The method of claim 1 wherein said fluxing agent is a weak acid.
Claim 12
Dependent Claim
24 words
The method of claim 10 wherein said acid is sufficiently volatile so that it substantially evaporates from said composite within 1 hour after processing.
Claim 13
Dependent Claim
44 words
The method process of claim 1 wherein said metal layer is melted by heating said substrate, metal layer, metal oxide layer and protective polymer to a temperature of between about 115° C. and about 200° C. for between about 0.1 and about 5 seconds.
Claim 14
Dependent Claim
16 words
The method of claim 1 wherein said metal oxide film is optically transparent and electrically conductive.
Claim 15
Independent Claim
178 words
A method for forming a metal/polymer composite comprising the steps: (a) providing a chamber having a substantial vacuum therein; (b) forming a metal vapor in said chamber by evaporation of a metal selected from the group consisting of indium, indium-tin, tin, cadmium, cadmium-tin, mixtures thereof, and such metals, alloys and mixtures which have been doped with antimony or flourine; (c) depositing said vapor on said substrate to form a metal layer at least about 500 angstroms thick on a polymeric substrate, said metal layer having an exposed substrate; (d) heating said polymeric substrate and said metal layer in the presence of oxygen to a temperature of between about 90° C. and about 150° C. for a time sufficient to form a metal oxide layer of between about 50 and about 100 Angstroms thick on said exposed surface; (e) contacting said metal oxide layer with an effective amount of week acid; (f) coating said oxide layer with a protective polymer layer; (g) heating said composite to a temperature sufficient to melt said metal layer and form discrete metal microspheres;
Claim 16
Independent Claim
178 words
A method for forming a metal/polymer composite comprising the steps: (a) providing a chamber having a substantial vacuum therein; (b) forming a metal vapor in said chamber by evaporation of a metal selected from the group consisting of indium, indium-tin, tin, cadmium, cadmium-tin, mixtures thereof, and such metals, alloys and mixtures which have been doped with antimony or flourine; (c) depositing said vapor on said substrate to form a metal layer at least about 500 angstroms thick on a polymeric substrate, said metal layer having an exposed substrate; (d) heating said polymeric substrate and said metal layer in the presence of oxygen to a temperature of between about 90° C. and about 150° C. for a time sufficient to form a metal oxide layer of between about 50 and about 100 Angstroms thick on said exposed surface; (e) contacting said metal oxide layer with an effective amount of week acid; (f) coating said oxide layer with a protective polymer layer; (g) heating said composite to a temperature sufficient to melt said metal layer and form discrete metal microspheres;
Claim 17
Dependent Claim
15 words
The method of claim 14 wherein said metal is evaporated by means of electron-beam evaporation.
Claim 18
Dependent Claim
26 words
The method of claim 14 wherein said effective amount of acid is dissolved in said protective polymer and the mixture coated onto said metal oxide layer.
Claim 19
Dependent Claim
45 words
A metal/polymer composite comprising: (a) a substrate; supported by said (b) a metal oxide layer substrate, said metal oxide layer comprising discrete microspheres of said metal embedded in a continuous layer of said metal oxide; and (c) a protective polymer overlying said metal oxide layer.
Claim 20
Dependent Claim
45 words
A metal/polymer composite comprising: (a) a substrate; supported by said (b) a metal oxide layer substrate, said metal oxide layer comprising discrete microspheres of said metal embedded in a continuous layer of said metal oxide; and (c) a protective polymer overlying said metal oxide layer.
Claim 21
Dependent Claim
28 words
The composite of claim 17 wherein said metal is selected from the group consisting of indium, indium-tin, tin, cadmium, cadmium-tin, and such metals doped with antimony or fluorine.
Claim 22
Dependent Claim
11 words
The composite of claim 18 wherein said substrate comprises a polymer.
Claim 23
Dependent Claim
32 words
The composite of claim 19 wherein said metal is selected from the group consisting of substantially pure indium and an indium-tin alloy having between about 5% and about 25% tin by weight.
Claim 24
Dependent Claim
19 words
The composite of claim 19 wherein said continuous oxide layer is between about 50 and about 100 angstroms thick.
Claim 25
Dependent Claim
22 words
The composite of claim 20 wherein said discrete metal microspheres have an average diameter of between about 0.5 and about 3.0 micrometers.
Claim 26
Dependent Claim
14 words
The composite of claim 18 wherein said composite is optically transparent and electrically conductive.
Claim 27
Dependent Claim
12 words
An opaque metal polymer composite made by the method of claim 14.
Claim 28
Dependent Claim
13 words
A substantially transparent metal polymer composite made by the method of claim 14.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1993-02-26 | 1993-08-28 | 1994-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-26 | 1997-08-28 | 1998-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-02-26 | 2001-08-28 | 2002-02-27 | $7700.00 | Window Closed / Lapsed |