US3795590A - Process for coloring aluminum and alloys of aluminum having an anodized surface - Google Patents
Process for coloring aluminum and alloys of aluminum having an anodized surface Download PDFInfo
- Publication number
- US3795590A US3795590A US00886330A US3795590DA US3795590A US 3795590 A US3795590 A US 3795590A US 00886330 A US00886330 A US 00886330A US 3795590D A US3795590D A US 3795590DA US 3795590 A US3795590 A US 3795590A
- Authority
- US
- United States
- Prior art keywords
- aluminum
- metal
- electrolysis
- color
- colored
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 229910052782 aluminium Inorganic materials 0.000 title abstract description 29
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 title abstract description 29
- 229910045601 alloy Inorganic materials 0.000 title abstract description 13
- 239000000956 alloy Substances 0.000 title abstract description 13
- 238000000034 method Methods 0.000 title description 36
- 238000004040 coloring Methods 0.000 title description 7
- 238000005868 electrolysis reaction Methods 0.000 abstract description 34
- 239000002245 particle Substances 0.000 abstract description 9
- 239000003086 colorant Substances 0.000 abstract description 8
- 239000003792 electrolyte Substances 0.000 abstract description 8
- 238000005260 corrosion Methods 0.000 abstract description 6
- 230000007797 corrosion Effects 0.000 abstract description 6
- 238000007789 sealing Methods 0.000 abstract description 6
- XYXNTHIYBIDHGM-UHFFFAOYSA-N ammonium thiosulfate Chemical compound [NH4+].[NH4+].[O-]S([O-])(=O)=S XYXNTHIYBIDHGM-UHFFFAOYSA-N 0.000 abstract description 5
- 229910052783 alkali metal Inorganic materials 0.000 abstract description 4
- 238000002048 anodisation reaction Methods 0.000 abstract description 4
- 150000001875 compounds Chemical class 0.000 abstract description 4
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 abstract description 4
- 150000001340 alkali metals Chemical class 0.000 abstract description 3
- 239000000470 constituent Substances 0.000 abstract description 3
- 238000004519 manufacturing process Methods 0.000 abstract description 3
- 238000000576 coating method Methods 0.000 description 13
- 229910052751 metal Inorganic materials 0.000 description 12
- 239000002184 metal Substances 0.000 description 12
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 12
- 230000000694 effects Effects 0.000 description 11
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 10
- 238000009835 boiling Methods 0.000 description 10
- 239000001117 sulphuric acid Substances 0.000 description 10
- 235000011149 sulphuric acid Nutrition 0.000 description 10
- 239000011248 coating agent Substances 0.000 description 9
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 8
- 150000003839 salts Chemical class 0.000 description 8
- 239000000243 solution Substances 0.000 description 8
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 7
- 239000007864 aqueous solution Substances 0.000 description 7
- 229910052802 copper Inorganic materials 0.000 description 7
- 239000010949 copper Substances 0.000 description 7
- 239000010410 layer Substances 0.000 description 7
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 6
- 239000004133 Sodium thiosulphate Substances 0.000 description 5
- 150000002815 nickel Chemical class 0.000 description 5
- AKHNMLFCWUSKQB-UHFFFAOYSA-L sodium thiosulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=S AKHNMLFCWUSKQB-UHFFFAOYSA-L 0.000 description 5
- 235000019345 sodium thiosulphate Nutrition 0.000 description 5
- MQRWBMAEBQOWAF-UHFFFAOYSA-N acetic acid;nickel Chemical compound [Ni].CC(O)=O.CC(O)=O MQRWBMAEBQOWAF-UHFFFAOYSA-N 0.000 description 4
- ARUVKPQLZAKDPS-UHFFFAOYSA-L copper(II) sulfate Chemical compound [Cu+2].[O-][S+2]([O-])([O-])[O-] ARUVKPQLZAKDPS-UHFFFAOYSA-L 0.000 description 4
- 238000004090 dissolution Methods 0.000 description 4
- 239000012153 distilled water Substances 0.000 description 4
- 229910052759 nickel Inorganic materials 0.000 description 4
- 229940078494 nickel acetate Drugs 0.000 description 4
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 4
- 229910001220 stainless steel Inorganic materials 0.000 description 4
- 239000010935 stainless steel Substances 0.000 description 4
- DHCDFWKWKRSZHF-UHFFFAOYSA-L thiosulfate(2-) Chemical compound [O-]S([S-])(=O)=O DHCDFWKWKRSZHF-UHFFFAOYSA-L 0.000 description 4
- 229910000838 Al alloy Inorganic materials 0.000 description 3
- 150000002736 metal compounds Chemical class 0.000 description 3
- 239000002344 surface layer Substances 0.000 description 3
- 239000002253 acid Substances 0.000 description 2
- 229910017052 cobalt Inorganic materials 0.000 description 2
- 239000010941 cobalt Substances 0.000 description 2
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 2
- 150000001879 copper Chemical class 0.000 description 2
- 238000000151 deposition Methods 0.000 description 2
- 238000007654 immersion Methods 0.000 description 2
- 229910052697 platinum Inorganic materials 0.000 description 2
- 238000005498 polishing Methods 0.000 description 2
- 239000012047 saturated solution Substances 0.000 description 2
- 229910000906 Bronze Inorganic materials 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 1
- -1 alkali metal thiosulphate Chemical class 0.000 description 1
- 238000007743 anodising Methods 0.000 description 1
- 239000011449 brick Substances 0.000 description 1
- 239000010974 bronze Substances 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 238000009500 colour coating Methods 0.000 description 1
- KUNSUQLRTQLHQQ-UHFFFAOYSA-N copper tin Chemical compound [Cu].[Sn] KUNSUQLRTQLHQQ-UHFFFAOYSA-N 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- FGRVOLIFQGXPCT-UHFFFAOYSA-L dipotassium;dioxido-oxo-sulfanylidene-$l^{6}-sulfane Chemical compound [K+].[K+].[O-]S([O-])(=O)=S FGRVOLIFQGXPCT-UHFFFAOYSA-L 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000011817 metal compound particle Substances 0.000 description 1
- 239000002923 metal particle Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 238000010517 secondary reaction Methods 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D11/00—Electrolytic coating by surface reaction, i.e. forming conversion layers
- C25D11/02—Anodisation
- C25D11/04—Anodisation of aluminium or alloys based thereon
- C25D11/12—Anodising more than once, e.g. in different baths
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D11/00—Electrolytic coating by surface reaction, i.e. forming conversion layers
- C25D11/02—Anodisation
- C25D11/04—Anodisation of aluminium or alloys based thereon
- C25D11/18—After-treatment, e.g. pore-sealing
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D11/00—Electrolytic coating by surface reaction, i.e. forming conversion layers
- C25D11/02—Anodisation
- C25D11/04—Anodisation of aluminium or alloys based thereon
- C25D11/18—After-treatment, e.g. pore-sealing
- C25D11/20—Electrolytic after-treatment
- C25D11/22—Electrolytic after-treatment for colouring layers
Definitions
- the process of this invention makes use successively of two different electrolysis baths whereby new colors are capable of being obtained while retaining all of the advantages of the process previously described.
- the use of copper salts in the coloring bath operates to produce colors ranging from pink to copper red to bright red whereas the process of this invention makes it possible to obtain additional colors such as bright yellow and brick color with the same copper salts.
- the surface of the aluminum or alloy of aluminum to be colored is first provided in the conventional manner with a porous layer of aluminum oxide, as by anodization in an acid bath, preferably a sulphuric acid.
- Colored particles of the metal or metal compound are deposited into the portion of the porous layer by alternating current electrolysis in which the aluminum or alloy of aluminum is suspended as an electrode in the elec- 3,795,590 1C Patented Mar.
- the aluminum object containing the temporary colored coating, which has been deposited by alternating current electrolysis is then subjected to anodic treatment by mounting the object as an anode in an electrolysis bath through which direct current or rectified unfiltered current is passed.
- the electrolysis bath which is employed in the anodic treatment with direct current electrolysis comprises an aqueous solution containing sodium thiosulphate in an amount within the range of 1 to 100 g./liter and preferably 5 to 20 g./liter.
- sodium thiosulphate ammonium thiosulphate or other alkali metal thiosulphate such as potassium thiosulphate may be used.
- the cathode use can be made of platinum, stainless steel, or a metal such as copper or nickel.
- the eflfect of anodic treatment is to modify the temporary color finish.
- the anodic treatment is carried out at substantially constant current density within the range of 0.1 to 5 a./dm. and preferably within the range of 0.1 to 1 a./dm. or at a substantially constant voltage within the range of 10 to volts or preferably within the range of 15 to 30 volts.
- the electrolyte is employed generally within the range of 15 to 50 C. and preferably within the range of 18 to 25 C.
- the desired results can be obtained by anodic treatment under the conditions described in a time span of /6 to 30 minutes and generally within the range of /2 to 15 minutes.
- the temporary color effect lightens and may even disappear completely if continued for a sufficiently long period of time. This is indicative of some type of dissolution of the colored particles under the anodic treatment described.
- the colored finish obtained after anodic treatment can be fixed by sealing in the conventional manner such as by boiling water, preferably containing dissolved nickel salts, or by other conventional means such as varnishing or the like.
- the final color finish obtained is governed both by the temporary color effect obtained during the coloring treatment by alternating current electrolysis and by duration of the modifying anodic treatment.
- the appearance of the final color effect is somewhat related to the surface quality of the object before the layer of alumina is formed by anodization.
- An originally brilliant or shiny surface yields color finishes which will be brilliant.
- the final color will appear dull or mat, but it is therefore of advantage to modify the surface characteristics of the object before coating, such modification being effected by such well known means as polishing, butfing, satinizing, and the like, depending upon the final color effect that is desired.
- a mat surface is obtained by cleaning the object for 10 minutes at 50 C.
- anoclic treatment to modify the temporary color effect wherein the object is mounted as an anode of an electrolysis cell through which direct current or unfiltered rectified current is passed and in which the electrolyte contains sodium thiosulphate and/or other alkali metal or ammonium thiosulphate and then preferably,
- EXAMPLE 1 v A 99.5% pure and previously cleaned aluminum sheet is anodized by mounting as an electrode in a bath containing 200 g./liter of sulphuric acid for a period of 30 minutes at 20 C. at a current density of 1.5 a./dm.
- the sheet is then mounted as the anode in an electrolysis cell in which the electrolyte is an aqueous solution of sodium thiosulphate, Na S- O -5H O', having a concentration of 10 g./liter.
- Direct current is passed for a perod of 10 minutes at a density of 0.4 a./dm. with the temperature of the bath being about 20 C.
- the sheet changes color to copper red which becomes a brick-like shade after 30 minutes treatment in boiling distilled water.
- the color effect that is obtained is uniform and resistant to corrosion and to ultra-violet rays.
- EXAMPLE 2 An aluminum alloy object containing 0.5% of Si and 0.5 of Mg is mechanically surface polished and then anodized in a sulphuric acid bath to produce a porous surface layer of alumina having a thickness of 16 -microns. The object is then colored in an electrolysis cell fed with alternating current in which the electrolyte is formulated of an aqueous solution of 10 g./liter copper sulphate'in sulphuric acid solution. After 3 minutes treatment at 12 volts, an object which is dark red in color is produced; The object is then mounted as an anode in another electrolysis cell containing 15 g./liter of sodium thiosulphatein aqueous solution.
- EXAMPLE 3 A sheet of aluminum alloy containing 0.6% of Mg is provided chemically with a gloss surface finish and then anodized in a conventional manner in a sulphuric acid bath to provide a porous surface layer of alumina having a thickness of 20 microns. It is then mounted as an elec trode in an electrolysis cell fed with alternating current in which the electrolyte is an aqueous solution of 3-10% copper sulphate in sulphuric acid, until a dark red color effect is obtained. The colored sheet is then mounted as an anode in another electrolysis cell fed with continuous direct current in which the electrolyte is an aqueous solution of sodium thiosulphate in a concentration of 20 g./ liter.
- EXAMPLE 4 An object of an aluminum alloy containing 1% Si, 1% Mg and 1% Mn is electrolytically polished to provide a gloss surface finish and then anodized in a sulphuric acid bath to provide a porous surface layer of alumina having a thickness of 8 microns. The anodized layer is then colored in a sulphuric acid solution of 15% by weight copper sulphate, using alternating current, until a black color finish is obtained. The section is then mounted as the anode of another electrolysis cell containing an aqueous solution of ammonium thiosulphate in a concentration of 12 g./liter. The cell is fed with rectified unfiltered current of 0.2 a./dm. for 10 minutes at 20 C.
- the color intensity is reduced as by partial dissolution. It takes on a brick-like color after treatment in boiling distilled water containing 1 g./liter of nickel acetate.
- the brick-like color is highly uniform and resistant to corrosion and to ultra-violet rays.
- the metal salt which is dissolved in the electrolysis bath for the deposition of colored particles into the porous surface of alumina is a salt of a metal selected from the group consisting of copper, nickel and cobalt.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Electroplating Methods And Accessories (AREA)
- Other Surface Treatments For Metallic Materials (AREA)
- Electrochemical Coating By Surface Reaction (AREA)
- Application Of Or Painting With Fluid Materials (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR179790 | 1968-12-23 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3795590A true US3795590A (en) | 1974-03-05 |
Family
ID=8658789
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US00886330A Expired - Lifetime US3795590A (en) | 1968-12-23 | 1969-12-18 | Process for coloring aluminum and alloys of aluminum having an anodized surface |
Country Status (13)
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3915813A (en) * | 1972-11-21 | 1975-10-28 | Showa Aluminium Co Ltd | Method for electrolytically coloring aluminum articles |
| US4024039A (en) * | 1972-08-31 | 1977-05-17 | Honny Chemicals Company, Ltd. | Coloring methods for aluminum and aluminum alloys |
| US4042471A (en) * | 1975-03-05 | 1977-08-16 | Yoshida Kogyo Kabushiki Kaisha | Process for electrolytically coloring aluminum and aluminum alloys |
| US4042469A (en) * | 1975-03-05 | 1977-08-16 | Yoshida Kogyo Kabushiki Kaisha | Process for electrolytically coloring aluminum and aluminum alloys in gold |
| US4043880A (en) * | 1975-07-24 | 1977-08-23 | Sumitomo Aluminum Smelting Co., Ltd. | Method for producing green-colored anodic oxide film on aluminum or aluminum base alloy articles |
| US4288299A (en) * | 1978-05-22 | 1981-09-08 | Alcan Research And Development Limited | Enhanced hydrothermal sealing of anodized aluminum |
| US4939044A (en) * | 1981-06-05 | 1990-07-03 | Fuji Photo Film Co., Ltd. | Aluminum alloy support for lithographic printing plate |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS575893A (en) * | 1980-06-16 | 1982-01-12 | Fujikura Ltd | Surface treating method for porous metallic article |
| US4526671A (en) * | 1982-09-24 | 1985-07-02 | Pilot Man-Nen-Hitsu Kabushiki Kaisha | Surface treatment of aluminum or aluminum alloys |
-
1968
- 1968-12-23 FR FR1605100D patent/FR1605100A/fr not_active Expired
-
1969
- 1969-12-18 US US00886330A patent/US3795590A/en not_active Expired - Lifetime
- 1969-12-18 DE DE19691963587 patent/DE1963587B2/de active Pending
- 1969-12-19 GB GB61895/69A patent/GB1291607A/en not_active Expired
- 1969-12-20 RO RO61928A patent/RO54852A/ro unknown
- 1969-12-22 NL NL6919219A patent/NL6919219A/xx unknown
- 1969-12-22 LU LU60070D patent/LU60070A1/xx unknown
- 1969-12-22 CA CA070609A patent/CA926808A/en not_active Expired
- 1969-12-22 SE SE17746/69A patent/SE360393B/xx unknown
- 1969-12-22 CH CH1903369A patent/CH508734A/fr not_active IP Right Cessation
- 1969-12-22 ES ES374797A patent/ES374797A1/es not_active Expired
- 1969-12-23 JP JP44103704A patent/JPS4927492B1/ja active Pending
- 1969-12-23 BE BE743617D patent/BE743617A/xx unknown
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4024039A (en) * | 1972-08-31 | 1977-05-17 | Honny Chemicals Company, Ltd. | Coloring methods for aluminum and aluminum alloys |
| US3915813A (en) * | 1972-11-21 | 1975-10-28 | Showa Aluminium Co Ltd | Method for electrolytically coloring aluminum articles |
| US4042471A (en) * | 1975-03-05 | 1977-08-16 | Yoshida Kogyo Kabushiki Kaisha | Process for electrolytically coloring aluminum and aluminum alloys |
| US4042469A (en) * | 1975-03-05 | 1977-08-16 | Yoshida Kogyo Kabushiki Kaisha | Process for electrolytically coloring aluminum and aluminum alloys in gold |
| US4043880A (en) * | 1975-07-24 | 1977-08-23 | Sumitomo Aluminum Smelting Co., Ltd. | Method for producing green-colored anodic oxide film on aluminum or aluminum base alloy articles |
| US4288299A (en) * | 1978-05-22 | 1981-09-08 | Alcan Research And Development Limited | Enhanced hydrothermal sealing of anodized aluminum |
| US4939044A (en) * | 1981-06-05 | 1990-07-03 | Fuji Photo Film Co., Ltd. | Aluminum alloy support for lithographic printing plate |
Also Published As
| Publication number | Publication date |
|---|---|
| RO54852A (enrdf_load_stackoverflow) | 1973-05-17 |
| BE743617A (enrdf_load_stackoverflow) | 1970-06-23 |
| JPS4927492B1 (enrdf_load_stackoverflow) | 1974-07-18 |
| SE360393B (enrdf_load_stackoverflow) | 1973-09-24 |
| GB1291607A (en) | 1972-10-04 |
| LU60070A1 (enrdf_load_stackoverflow) | 1970-06-26 |
| ES374797A1 (es) | 1972-04-16 |
| NL6919219A (enrdf_load_stackoverflow) | 1970-06-25 |
| FR1605100A (enrdf_load_stackoverflow) | 1973-01-12 |
| CH508734A (fr) | 1971-06-15 |
| DE1963587A1 (de) | 1970-06-25 |
| DE1963587B2 (de) | 1971-02-25 |
| CA926808A (en) | 1973-05-22 |
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