Patent US4620813A successfully refreshed from Google Patents.
US3900601A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Treatment of thin metallic films for increased durability
Assignee: PPG Industries Inc
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Filing: 1973-09-28
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Granted: 1975-08-19
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Expires: 1993-09-28
Abstract
Abstract Thin metallic films, particularly transparent films, on substrates such as glass are heat treated and then are contacted with alkali metal dichromate solutions or the like to superficially oxidize the films making them more resistant to corrosion in a moist environment.
Inventors
- 👤 Helmut Franz
- 👤 David E Lecocq
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:25
CPC Classifications
C; C03; C03C; C03C17/00; C03C17/22; C03C17/23; C03C17/27; C03C17/06; C03C2217/00; C03C2217/20; C03C2217/21; C03C2217/217; C03C2217/228; C03C2217/25; C03C2217/251; C03C2217/253; C03C2217/261; C03C2218/00; C03C2218/10; C03C2218/11; C03C2218/30; C03C2218/32; C03C2218/322
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
142 words
A METHOD OF MAKING A TRANSPARENT METAL COATED GLASS ARTICLE COMPRISING THE STEPS OF DEPOSITING A TRANSPARENT METALLIC FILM OF IRON, COBALT, NICKEL, COPPER, OR MIXTURE THEREOF ON A SURFACE OF A GLASS SUBSTRATE, HEATING THE METALLIC FILM AND GLASS SUBSTRATE COMBINATION TO A TEMPERATURE WHICH IS AT LEAST 150*C. BUT BELOW A TEMPERATURE AT WHICH THE GLASS IS DISTORTED AND MAINTAINING THE COMBINATION WITHIN THAT TEMPERATURE RANGE FOR A TIME SUFFICIENT TO SUBSTANTIALLY REDUCE THE ELECTRICAL RESISTANCE OF THE METALLIC FILM, AND THEREAFTER CONTACTING THE METALLIC FILM WITH AN AQUEOUS SOLUTION COMPRISING WATER AND A WEAK OXIDIZING AGENT SELECTED FROM THE GROUP CONSISTING OF ALKALI METAL DICHROMATES, AMMONIUM DICHROMATE, ALKALI METAL PERBORATES, AMMONIUM PERBORATE, ALKALI METAL PERMANGANATES AND AMMONIUM PERMANGANATE PRESENT AS 0.1 TO 10 PERCENT BY WEIGHT OF THE SOLUTION, THE SOLUTION HAVING A PH OF AT LEAST ABOUT 4.
Claim 2
Independent Claim
142 words
A METHOD OF MAKING A TRANSPARENT METAL COATED GLASS ARTICLE COMPRISING THE STEPS OF DEPOSITING A TRANSPARENT METALLIC FILM OF IRON, COBALT, NICKEL, COPPER, OR MIXTURE THEREOF ON A SURFACE OF A GLASS SUBSTRATE, HEATING THE METALLIC FILM AND GLASS SUBSTRATE COMBINATION TO A TEMPERATURE WHICH IS AT LEAST 150*C. BUT BELOW A TEMPERATURE AT WHICH THE GLASS IS DISTORTED AND MAINTAINING THE COMBINATION WITHIN THAT TEMPERATURE RANGE FOR A TIME SUFFICIENT TO SUBSTANTIALLY REDUCE THE ELECTRICAL RESISTANCE OF THE METALLIC FILM, AND THEREAFTER CONTACTING THE METALLIC FILM WITH AN AQUEOUS SOLUTION COMPRISING WATER AND A WEAK OXIDIZING AGENT SELECTED FROM THE GROUP CONSISTING OF ALKALI METAL DICHROMATES, AMMONIUM DICHROMATE, ALKALI METAL PERBORATES, AMMONIUM PERBORATE, ALKALI METAL PERMANGANATES AND AMMONIUM PERMANGANATE PRESENT AS 0.1 TO 10 PERCENT BY WEIGHT OF THE SOLUTION, THE SOLUTION HAVING A PH OF AT LEAST ABOUT 4.
Claim 3
Dependent Claim
23 words
The method of claim 1 wherein the weak oxidizing agent is selected from the group consisting of alkali metal dichromates and ammonium dichromate.
Claim 4
Dependent Claim
13 words
The method of claim 1 wherein the weak oxidizing agent is potassium dichromate.
Claim 5
Dependent Claim
22 words
The method of claim 3 wherein the aqueous solution of potassium dichromate comprises on the basis of 1 liter of water: n
Claim 6
Dependent Claim
32 words
The method of claim 3 wherein the step of contacting the metallic film with an aqueous solution containing potassium dichromate is carried out at a temperature between about 20*C and about 100*C.
Claim 7
Dependent Claim
30 words
The method of claim 5 wherein the metal of the film is copper and wherein the contacting step is carried out at a temperature between about 25*C. and about 70*C.
Claim 8
Dependent Claim
32 words
The method of claim 5 wherein the metal film is iron, cobalt, nickel or mixtures thereof and wherein the contacting step is carried out at a temperature between about 80*C. and 100*C.
Claim 9
Dependent Claim
55 words
The method of claim 1 wherein the combination is maintained within the temperature range from at least about 150*C. to below a temperature at which the glass is distorted for a time sufficient to decrease the electrical resistance of the metallic film to below about 50 percent of its initial electrical resistance prior to heating.
Claim 10
Dependent Claim
36 words
The method of claim 8 wherein the temperature of the combination is maintained until the electrical resistance of the metallic film has decreased at least about 90 percent of its initial electrical resistance prior to heating.
Claim 11
Dependent Claim
17 words
The method of claim 8 wherein the step of heating is carried out in a reducing atmosphere.
Claim 12
Dependent Claim
24 words
The method of claim 1 wherein the aqueous solution comprising a weak oxidizing agent has a pH of from about 4 to about 5.
References Cited (Backward Citations)
US2788292A
Cited
US2690402A
Cited
US3093509A
Cited
US3088846A
Cited
US3537944A
Cited
US3674517A
Cited
US3708350A
Cited
US3694337A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-08-18 | 1979-02-17 | 1979-08-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-18 | 1983-02-17 | 1983-08-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-18 | 1987-02-17 | 1987-08-19 | $7700.00 | Window Closed / Lapsed |