US4400246A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for applying barrier layer anodic coatings
Assignee: International Business Machines Corp
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Filing: 1982-06-28
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Granted: 1983-08-23
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Expires: 2002-06-28
Abstract
Abstract A barrier anodizing process for an aluminum alloy substrate employs an anodizing current having a density between 20 and 300 milliamps/cm 2 to produce a 300 volt barrier layer in respectively 60 and 4 second
Inventors
- 👤 George A. Condas
- 👤 Saad K. Doss
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 02:49
CPC Classifications
C; C25; C25D; C25D11/00; C25D11/02; C25D11/04
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
65 words
A method of providing a barrier layer on the surface of an aluminum substrate comprising the steps of barrier anodizing said substrate at an anodizing current density of at least 20 milliamperes/cm 2 for a very short period of time not to appreciably exceed the barrier formation time, said barrier anodizing being conducted in an acidic bath having a pH of between 5 and 7.
Claim 2
Independent Claim
65 words
A method of providing a barrier layer on the surface of an aluminum substrate comprising the steps of barrier anodizing said substrate at an anodizing current density of at least 20 milliamperes/cm 2 for a very short period of time not to appreciably exceed the barrier formation time, said barrier anodizing being conducted in an acidic bath having a pH of between 5 and 7.
Claim 3
Dependent Claim
22 words
A method in accordance with claim 1 in which said barrier anodizing current is maintained between 20 and 300 milliamperes/cm 2 .
Claim 4
Dependent Claim
22 words
A method in accordance with claim 1 in which the voltage in said barrier anodizing is maintained between 150 and 500 volts.
Claim 5
Dependent Claim
22 words
A method in accordance with claim 2 in which said barrier anodizing period of time is between 60 seconds and 4 seconds.
References Cited (Backward Citations)
US2408910A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-08-22 | 1987-02-21 | 1987-08-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-08-22 | 1991-02-21 | 1991-08-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-08-22 | 1995-02-21 | 1995-08-23 | $7700.00 | Window Closed / Lapsed |