US3929612A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for electrolytically coloring the anodically oxidized coating on aluminum or aluminum base alloys
Assignee: Sumitomo Chemical Co Ltd
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Filing: 1974-10-21
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Granted: 1975-12-30
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Expires: 1994-10-21
Abstract
Abstract In the process for electrolytically coloring an anodically oxidized coating on an aluminum or aluminum base alloy article by subjecting the anodized aluminum or aluminum base alloy article as a cathode to an electrolytic coloring treatment with a direct current in an electrolytic coloring bath containing a nickel salt, an improvement which comprises conducting the electrolytic coloring treatment at a pH in the range of from 2.0 to 5.5 to obtain a uniformly colored film.
Inventors
- 👤 Kiyomi Yanagida
- 👤 Tadashi Hirokane
- 👤 Tadashi Tsukiyasu
- 👤 Tomoari Sato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 04:45
CPC Classifications
C; C25; C25D; C25D11/00; C25D11/02; C25D11/04; C25D11/18; C25D11/20; C25D11/22
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
124 words
IN A PROCESS FOR ELECTROLYTICALLY COLORING AN ANODICALLY OXIDIZED COATING ON AN ALUMINUM OR ALUMINUM ALLOY ARTICLE COMPRISING SUBJECTING SAID ARTICLE TO ANODIC OXIDATION IN AN AQUEOUS ANODIC OXIDATION BATH CONSISTING ESSENTIALLY OF SULFURIC ACID OR AN AROMATIC SULFONIC ACID TO FORM AN OXIDIZED FILM OF A THICKNESS OF AT LEAST 6 MICRONS AND ELECTROLYZING SAID ANODIC OXIDIZED ARTIC;E AS A CATHODE IMMERSED IN AN AQUEOUS ELECTROLYTIC COLORING BATH CONTAINING A WATER-SOLUBLE NICKEL SALE SELECTED FROM THE GROUP CONSISTING OF NICKEL SULFATE, NICKEL CHLORIDE AND NICKEL ACETATE USING A DIRECT CURRENT, THE IMPROVEMENT OF OBTAINING UNIFORMLY COLORED COATING ON THE ALUMINUM ARTICLE BY MAINTAINING THE PH OF SAID ELECTROLYTIC COLORING BATH IN A RANGE OF FROM 2.0 TO 5.5 DURING SAID ELECTROLYTIC COLORING TREATMENT.
Claim 2
Dependent Claim
124 words
IN A PROCESS FOR ELECTROLYTICALLY COLORING AN ANODICALLY OXIDIZED COATING ON AN ALUMINUM OR ALUMINUM ALLOY ARTICLE COMPRISING SUBJECTING SAID ARTICLE TO ANODIC OXIDATION IN AN AQUEOUS ANODIC OXIDATION BATH CONSISTING ESSENTIALLY OF SULFURIC ACID OR AN AROMATIC SULFONIC ACID TO FORM AN OXIDIZED FILM OF A THICKNESS OF AT LEAST 6 MICRONS AND ELECTROLYZING SAID ANODIC OXIDIZED ARTIC;E AS A CATHODE IMMERSED IN AN AQUEOUS ELECTROLYTIC COLORING BATH CONTAINING A WATER-SOLUBLE NICKEL SALE SELECTED FROM THE GROUP CONSISTING OF NICKEL SULFATE, NICKEL CHLORIDE AND NICKEL ACETATE USING A DIRECT CURRENT, THE IMPROVEMENT OF OBTAINING UNIFORMLY COLORED COATING ON THE ALUMINUM ARTICLE BY MAINTAINING THE PH OF SAID ELECTROLYTIC COLORING BATH IN A RANGE OF FROM 2.0 TO 5.5 DURING SAID ELECTROLYTIC COLORING TREATMENT.
Claim 3
Dependent Claim
13 words
The process according to claim 1, wherein said nickel salt is nickel sulfate.
Claim 4
Dependent Claim
15 words
The process according to claim 1, wherein said electrolytic coloring bath further contains boric acid.
Claim 5
Dependent Claim
25 words
The process according to claim 1, wherein the pH of the electrolytic coloring bath is maintained at 3.0 to 4.5 during said electrolytic coloring treatment.
Claim 6
Dependent Claim
31 words
The process according to claim 1, wherein the pH of the electrolytic coloring bath is maintained at 2.0 to 5.5 by adding a small amount of sulfuric acid to the bath.
Claim 7
Dependent Claim
31 words
The process accoding to claim 1, wherein the pH of the electrolytic coloring bath is maintained at 2.0 to 5.5 by adding a small amount of nickel hydrOxide to the bath.
Claim 8
Dependent Claim
31 words
The process according to claim 1, wherein the pH of the electrolytic coloring bath is maintained at 2.0 to 5.5 by passing the electrolytic coloring bath through an anion exchange resin.
Claim 9
Dependent Claim
18 words
The process according to claim 7, wherein said anion exchange resin is a weak basic anion exchange resin.
References Cited (Backward Citations)
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US3761362A
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US3759801A
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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) | 1978-12-29 | 1979-06-30 | 1979-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-29 | 1983-06-30 | 1983-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-29 | 1987-06-30 | 1987-12-30 | $7700.00 | Window Closed / Lapsed |