US3870608A - Process for coloring aluminum or aluminum alloys by anodizing with imperfectly rectified current - Google Patents
Process for coloring aluminum or aluminum alloys by anodizing with imperfectly rectified current Download PDFInfo
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- US3870608A US3870608A US359645A US35964573A US3870608A US 3870608 A US3870608 A US 3870608A US 359645 A US359645 A US 359645A US 35964573 A US35964573 A US 35964573A US 3870608 A US3870608 A US 3870608A
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- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 title claims abstract description 32
- 229910052782 aluminium Inorganic materials 0.000 title claims abstract description 30
- 238000007743 anodising Methods 0.000 title claims abstract description 12
- 238000000034 method Methods 0.000 title claims description 33
- 238000004040 coloring Methods 0.000 title claims description 21
- 229910000838 Al alloy Inorganic materials 0.000 title abstract description 17
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims abstract description 46
- 239000008151 electrolyte solution Substances 0.000 claims abstract description 21
- 239000004615 ingredient Substances 0.000 claims description 12
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 10
- -1 SULFAMATES Chemical class 0.000 claims description 9
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 8
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 8
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 claims description 8
- 229910052793 cadmium Inorganic materials 0.000 claims description 8
- BDOSMKKIYDKNTQ-UHFFFAOYSA-N cadmium atom Chemical compound [Cd] BDOSMKKIYDKNTQ-UHFFFAOYSA-N 0.000 claims description 8
- 229910052802 copper Inorganic materials 0.000 claims description 8
- 239000010949 copper Substances 0.000 claims description 8
- 229910052718 tin Inorganic materials 0.000 claims description 8
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 7
- 239000010941 cobalt Substances 0.000 claims description 7
- 229910017052 cobalt Inorganic materials 0.000 claims description 7
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims description 7
- 239000011135 tin Substances 0.000 claims description 7
- 229910052719 titanium Inorganic materials 0.000 claims description 7
- 239000010936 titanium Substances 0.000 claims description 7
- 239000011133 lead Substances 0.000 claims description 6
- 229910052759 nickel Inorganic materials 0.000 claims description 5
- 150000003467 sulfuric acid derivatives Chemical class 0.000 claims description 5
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 claims description 4
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 claims description 4
- 229910019142 PO4 Inorganic materials 0.000 claims description 4
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 claims description 4
- 229910045601 alloy Inorganic materials 0.000 claims description 4
- 239000000956 alloy Substances 0.000 claims description 4
- 150000001642 boronic acid derivatives Chemical class 0.000 claims description 4
- ZCDOYSPFYFSLEW-UHFFFAOYSA-N chromate(2-) Chemical compound [O-][Cr]([O-])(=O)=O ZCDOYSPFYFSLEW-UHFFFAOYSA-N 0.000 claims description 4
- 229910052742 iron Inorganic materials 0.000 claims description 4
- 150000002690 malonic acid derivatives Chemical class 0.000 claims description 4
- 229910052748 manganese Inorganic materials 0.000 claims description 4
- 239000011572 manganese Substances 0.000 claims description 4
- 229910052750 molybdenum Inorganic materials 0.000 claims description 4
- 239000011733 molybdenum Substances 0.000 claims description 4
- 150000003891 oxalate salts Chemical class 0.000 claims description 4
- 150000004760 silicates Chemical class 0.000 claims description 4
- 150000003890 succinate salts Chemical class 0.000 claims description 4
- 229910052726 zirconium Inorganic materials 0.000 claims description 4
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 claims description 3
- 150000001805 chlorine compounds Chemical class 0.000 claims description 3
- 150000002823 nitrates Chemical class 0.000 claims description 3
- 235000021317 phosphate Nutrition 0.000 claims description 3
- 150000003013 phosphoric acid derivatives Chemical class 0.000 claims description 3
- IIACRCGMVDHOTQ-UHFFFAOYSA-N sulfamic acid Chemical class NS(O)(=O)=O IIACRCGMVDHOTQ-UHFFFAOYSA-N 0.000 claims description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 claims 1
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 claims 1
- VJPLIHZPOJDHLB-UHFFFAOYSA-N lead titanium Chemical compound [Ti].[Pb] VJPLIHZPOJDHLB-UHFFFAOYSA-N 0.000 claims 1
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 claims 1
- 229910052751 metal Chemical class 0.000 abstract description 10
- 239000002184 metal Chemical class 0.000 abstract description 10
- 150000003839 salts Chemical class 0.000 abstract description 10
- 150000001450 anions Chemical class 0.000 abstract description 6
- 229940032330 sulfuric acid Drugs 0.000 description 16
- 238000005868 electrolysis reaction Methods 0.000 description 14
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 7
- 238000009835 boiling Methods 0.000 description 7
- 229910052799 carbon Inorganic materials 0.000 description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 7
- 239000000203 mixture Substances 0.000 description 6
- 238000000354 decomposition reaction Methods 0.000 description 4
- 150000002500 ions Chemical class 0.000 description 4
- 239000006103 coloring component Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- QYHFIVBSNOWOCQ-UHFFFAOYSA-N selenic acid Chemical compound O[Se](O)(=O)=O QYHFIVBSNOWOCQ-UHFFFAOYSA-N 0.000 description 2
- PANBYUAFMMOFOV-UHFFFAOYSA-N sodium;sulfuric acid Chemical compound [Na].OS(O)(=O)=O PANBYUAFMMOFOV-UHFFFAOYSA-N 0.000 description 2
- RCIVOBGSMSSVTR-UHFFFAOYSA-L stannous sulfate Chemical compound [SnH2+2].[O-]S([O-])(=O)=O RCIVOBGSMSSVTR-UHFFFAOYSA-L 0.000 description 2
- 229910000375 tin(II) sulfate Inorganic materials 0.000 description 2
- 229910000906 Bronze Inorganic materials 0.000 description 1
- QXZUUHYBWMWJHK-UHFFFAOYSA-N [Co].[Ni] Chemical compound [Co].[Ni] QXZUUHYBWMWJHK-UHFFFAOYSA-N 0.000 description 1
- 239000010974 bronze Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- KUNSUQLRTQLHQQ-UHFFFAOYSA-N copper tin Chemical compound [Cu].[Sn] KUNSUQLRTQLHQQ-UHFFFAOYSA-N 0.000 description 1
- BQJTUDIVKSVBDU-UHFFFAOYSA-L copper;sulfuric acid;sulfate Chemical compound [Cu+2].OS(O)(=O)=O.[O-]S([O-])(=O)=O BQJTUDIVKSVBDU-UHFFFAOYSA-L 0.000 description 1
- 238000007598 dipping method Methods 0.000 description 1
- 238000009713 electroplating Methods 0.000 description 1
- ZZUFCTLCJUWOSV-UHFFFAOYSA-N furosemide Chemical compound C1=C(Cl)C(S(=O)(=O)N)=CC(C(O)=O)=C1NCC1=CC=CO1 ZZUFCTLCJUWOSV-UHFFFAOYSA-N 0.000 description 1
- VOEYXMAFNDNNED-UHFFFAOYSA-N metolcarb Chemical compound CNC(=O)OC1=CC=CC(C)=C1 VOEYXMAFNDNNED-UHFFFAOYSA-N 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- ZMHKWSJKUQOPMJ-UHFFFAOYSA-N selenic acid sulfuric acid Chemical compound OS(O)(=O)=O.O[Se](O)(=O)=O ZMHKWSJKUQOPMJ-UHFFFAOYSA-N 0.000 description 1
- 238000002791 soaking Methods 0.000 description 1
- 229940079864 sodium stannate Drugs 0.000 description 1
- XMVONEAAOPAGAO-UHFFFAOYSA-N sodium tungstate Chemical compound [Na+].[Na+].[O-][W]([O-])(=O)=O XMVONEAAOPAGAO-UHFFFAOYSA-N 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 150000003464 sulfur compounds Chemical class 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
- C25D11/14—Producing integrally coloured layers
Definitions
- ABSTRACT Aluminum or aluminum alloys are colored by anodizing the aluminum or aluminum alloys in a sulfuric acid electrolytic solution containing oxyacid anion and/or metal salt by imperfectly rectified current.
- Japanese Patent Publication No. 9805/1969 aluminum or aluminum alloys are anodized to form a film and the resulting film is colored with an organic dye or inorganic coloring materials.
- Japanese Patent Publication Nos. 14053/1967, l2566/l969 and 19842/1971 and Studies on coloring of aluminum for architectural purposes using inorganic matierials, published by Aluminum Kenchiku Yohin Hyomen Shori Gijutsu Kenkyu Kumiai, Mar. 1, 1972 disclose a coloring process comprising adding various materials to an electrolytic solution and anodizing by AC, DC or a superimposed AC on DC, a so called one step electrolytic process.”
- electrolytic coloring of an aluminum anodized film in Denki Kagaku, Vol. 3, p. 20, 1935, and Study on Electrolytic coloring method read before the 44th Meeting of Kinzoku Hyomen Gijutsu Kyokai, 1971 discloses a so called two step electrolytic method" comprising producing an anodized oxide film on aluminum or aluminum alloy according to conventional procedure in the first step and subjecting the anodized article to AC or DC electrolysis by dipping the aluminum or aluminum alloy thus anodized in a solution of a metal salt where the aluminum of aluminum alloy is used as one electrode.
- the method in item l) above necessitates two vessels, i.e. an electrolytic vessel and a coloring vessel for soaking in a separate coloring bath.
- the two step electrolytic method in item (3) above necessitates two electrolytic vessels so that the operation is complicated.
- the method in item (2) above gives a monotonous color tone, and can not give varied color.
- the process of superimposed alternating current on direct current necessitates AC source, DC source and a rectifier-transformer.
- a process for coloring aluminum or aluminum alloys which comprises anodizing the article of aluminum or alloy of aluminum in a sulfuric acid electrolytic solution containing at least one ingridient selected from the group consisting of oxyacid anion and metal salt by imperfectly rectitied current.
- An object of this invention is to provide a novel coloring process capable of producing commercially excellent colored anodized film easily.
- a method of imperfectly rectifying current employed in this invention is that the rectifying is effected imperfectly by by-passing a part of the current by using a resistance upon rectifying single phase or three phase alternating current. This method is much more simple than the conventional process of superimposed alternating current on direct current the apparatus point of view. Further, current obtained by the method of imperfectly rectifying current has a negative component and a positive component which have'the same cycle and thereby there can be produced uniform colored anodized film.
- coloring is conducted in such a manner as shown below. While the oxyacid anion and/or metal salt added to the sulfuric acid electrolytic solution produced an anodized film on the aluminum or aluminum alloy article by imperfectly rectified current, S ion or negative ion components formed by decomposition of sulfuric acid in the electrolytic solution combines with the positive ion components formed by decomposition of oxyacid anion and- /or metal salt to produce a sulfur compound, a coloring component, in the oxide film layer. Since such coloring component is formed in the anodized film, a highly weatherproof colored film of excellent color can be easily obtained.
- Examples of the oxyacid ions which maybe added to the sulfuric acid electrolytic solution are SeOf", M00 W0 TeOf', CrOfi, ASO33 AsOfl, and V0
- Representative metal salts include sulfates, nitrates, phosphates, sulfamates, borates, 'chromates, dichromates, chlorides, silicates and organic acid salts such as oxalates, malonates, tartarates, succinates and the like of nickel cobalt, tin, copper, lead, titanium, cadmium, iron, molybdenum, zirconium and manganese.
- Prefera ble metal salts are sulfates ofnickel, cobalt, tin, copper, lead, titanium and cadmium.
- the amount of the oxyacid anion and/or metal salt to be added depends upon the type of oxyacid and metal salt. In general, the amount is determined by taking into consideration solubility in the sulfuric acid electrolytic solution, coloring property and economy, and usually ranges from about 0.1 to 200 g./l., preferred with from about 1 to 100 g./l. However, when the solubility in the electrolytic solution is too low, the coloring disadvantageously lowered.
- the ratio of positive component to negative component in the imperfectly rectified current is at least 2:l. Preferably such ratio is 2-20zl.
- the current density of the positive component is 0.5 6.0 A/dm with 1.0 3.0 A/dm preferred and that of the negative component is 0.05 6.0 A/dm with 0.1 3.0 A/dm preferred.
- the electrolysis was effected by using a carbon plate as one electrode with imperfectly rectified current, i.e. wherein the positive component has a current density of 2.0 A/dm and the negative component has a current density of 0.2 A/dm for 30 minutes to produce a film of bronze color.
- the colored film was treated with boiling water to seal.
- EXAMPLE 2 An aluminum plate treated in a way similar to Example 1 above was subjected to electrolysis in an electrolytic bath having the following composition at a bath temperature of 20C.
- EXAMPLE 3 An aluminum plate treated in a way similar to Example 1 above was subjected to electrolysis in an electrolytic bath having the following composition at a bath temperature of 20C.
- Sulfuric acid Selenic acid The electrolysis was effected by using a carbon plate as one electrode with imperfectly rectified current, i.e. wherein the positive component has a current density of 3.0 A/dm and the negative component has a current density of 0.2 A/dm for 40 minutes to produce a deep orange film. The resulting colored film was treated with boiling water to seal.
- EXAMPLE 4 An aluminum plate treated in a way similar to Example 1 above was subjected to electrolysis in an electrolytic bath having the following composition at a bath temperature of 25C.
- the electrolysis was conducted by using a carbon plate as one electrode with imperfectly rectified current, i.e. wherein the positive component has a current density of 3.0 A/dm and the negative component has a current density of 1.2 A/dm' for 30 minutes to produce a grayish film.
- the resulting colored film was treated with boiling water to seal.
- EXAMPLE 5 An aluminum plate treated in a way similar to Example l was subjected to electrolysis in an electrolytic bath having the following composition at a bath temperature of 25C.
- the resulting film was treated with boiling water to seal.
- EXAMPLE 6 An aluminum plate treated in a way similar to Example l was subjected to electrolysis in an electrolytic bath having the following composition at a bath temperature of 20C.
- the electrolysis was conducted by using a carbon plate as one electrode with imperfectly rectified current, i.e., wherein the positive component has a current density of 2.5 A/dm and the negative component has a current density of 0.2 A/dm for 30 minutes to produce a film of bronz color.
- the resulting colored film was treated with boiling water to seal.
- EXAMPLE 7 An aluminum plate treated in a way similar to Example l was subjected to electrolysis in an electrolytic bath having the following composition at a bath tem perature of 20C.
- the electrolysis was effected by using a carbon plate as one electrode with imperfectly rectified current, i.e. wherein positive component has a current density of 3.0 A/dm and the negative component has a current density of 0.3 A/dm' for 30 minutes to produce a grayish orange film.
- the resulting colored film was treated with boiling water to seal.
- a process for coloring an article of aluminum or alloys of aluminum comprising anodizing the article in a sulfuric acid electrolytic solution containing at least one ingredient selected from the group consisting of SeOf", M00 W0 TeOf, CrOf, CrO AsO AsOf, V0 sulfates.
- a process according to claim 1 wherein the ingredient contained in the sulfuricacid electrolytic solution is selected from the group consisting of a sulfate of nickel. cobalt. tin. copper. lead. titanium and cadmium.
- a process according to claim 1 wherein the current density of the positive component is approximately 1.0 to 3.0 A/dm and that of the negative component is approximately 0.1 to 3.0 A/dm 5.
- a process according to claim 1 wherein the ratio of positive component to negative component is approximately 2-20:l.
- a process according to claim 5 wherein the ingredient contained in the sulfuric acid electrolytic solution is selected from the group consisting of a sulfate of nickel, cobalt, tin, copper, lead, titanium and cadmium; wherein the amount of the ingredient in the sulfuric acid electrolytic solution is approximately l to 100 g./l.; and wherein the current density of the positive component is approximately 1.0 to 3.0 A/dm and that of the negative component is approximately 0.1 to 3.0 A/dm
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- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
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- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Electrochemical Coating By Surface Reaction (AREA)
- Electroplating And Plating Baths Therefor (AREA)
Abstract
Aluminum or aluminum alloys are colored by anodizing the aluminum or aluminum alloys in a sulfuric acid electrolytic solution containing oxyacid anion and/or metal salt by imperfectly rectified current.
Description
United States Patent 1 Mita [ PROCESS FOR COLORING ALUMINUM OR ALUMINUM ALLOYS BY ANODIZING WITH IMPERFECTLY RECTIFIED CURRENT [75] Inventor: Ikuo Mita, Tokyo, Japan [73] Assignee: Tokyo Metropolitan Government,
Tokyo, Japan [22] Filed: May 14, 1973 {21] Appl. No.1 359,645
[111 3,870,608 [451 Mar. 11, 1975 [56] References Cited UNITED STATES PATENTS 3,616,311 10/1971 Barkman 204/58 3,639,221 2/1972 Dorsey 204/58 OTHER PUBLICATIONS Electroplating Engineering Handbook, 2nd Ed., by A. K. Graham, 1962, page 670.
Primary Examiner-R. L. Andrews Attorney, Agent, or F irm-Shapiro and Shapiro [57] ABSTRACT Aluminum or aluminum alloys are colored by anodizing the aluminum or aluminum alloys in a sulfuric acid electrolytic solution containing oxyacid anion and/or metal salt by imperfectly rectified current.
6 Claims, No Drawings PROCESS FOR COLORING ALUMINUM OR ALUMINUM ALLOYS BY ANODIZING WITH IMPERFECTLY RECTIFIED CURRENT BACKGROUND OF THE INVENTION l. Field of the Invention This invention relates to a process for coloring aluminum or aluminum alloys by anodizing by imperfectly rectified current to form a colored film.
2. Description of the Prior Art Heretofore, there have been used various methods for coloring aluminum or aluminum alloys by anodizing with imperfectly rectified current to form a colored film.
(1) According to Japanese Patent Publication No. 9805/1969, aluminum or aluminum alloys are anodized to form a film and the resulting film is colored with an organic dye or inorganic coloring materials. (2) Japanese Patent Publication Nos. 14053/1967, l2566/l969 and 19842/1971 and Studies on coloring of aluminum for architectural purposes using inorganic matierials, published by Aluminum Kenchiku Yohin Hyomen Shori Gijutsu Kenkyu Kumiai, Mar. 1, 1972 disclose a coloring process comprising adding various materials to an electrolytic solution and anodizing by AC, DC or a superimposed AC on DC, a so called one step electrolytic process." (3) Japanese Patent Publication No. l7l5/l963, electrolytic coloring of an aluminum anodized film in Denki Kagaku, Vol. 3, p. 20, 1935, and Study on Electrolytic coloring method read before the 44th Meeting of Kinzoku Hyomen Gijutsu Kyokai, 1971 discloses a so called two step electrolytic method" comprising producing an anodized oxide film on aluminum or aluminum alloy according to conventional procedure in the first step and subjecting the anodized article to AC or DC electrolysis by dipping the aluminum or aluminum alloy thus anodized in a solution of a metal salt where the aluminum of aluminum alloy is used as one electrode.
Among the above mentioned known methods, the method in item l) above necessitates two vessels, i.e. an electrolytic vessel and a coloring vessel for soaking in a separate coloring bath. The two step electrolytic method in item (3) above necessitates two electrolytic vessels so that the operation is complicated. The method in item (2) above gives a monotonous color tone, and can not give varied color. Furthermore, the process of superimposed alternating current on direct current necessitates AC source, DC source and a rectifier-transformer.
SUMMARY OF THE INVENTION According to the present invention, there is provided a process for coloring aluminum or aluminum alloys which comprises anodizing the article of aluminum or alloy of aluminum in a sulfuric acid electrolytic solution containing at least one ingridient selected from the group consisting of oxyacid anion and metal salt by imperfectly rectitied current.
An object of this invention is to provide a novel coloring process capable of producing commercially excellent colored anodized film easily.
DESCRIPTION OF THE PREFERRED EMBODIMENTS A method of imperfectly rectifying current employed in this invention is that the rectifying is effected imperfectly by by-passing a part of the current by using a resistance upon rectifying single phase or three phase alternating current. This method is much more simple than the conventional process of superimposed alternating current on direct current the apparatus point of view. Further, current obtained by the method of imperfectly rectifying current has a negative component and a positive component which have'the same cycle and thereby there can be produced uniform colored anodized film.
According to the present invention. coloring is conducted in such a manner as shown below. While the oxyacid anion and/or metal salt added to the sulfuric acid electrolytic solution produced an anodized film on the aluminum or aluminum alloy article by imperfectly rectified current, S ion or negative ion components formed by decomposition of sulfuric acid in the electrolytic solution combines with the positive ion components formed by decomposition of oxyacid anion and- /or metal salt to produce a sulfur compound, a coloring component, in the oxide film layer. Since such coloring component is formed in the anodized film, a highly weatherproof colored film of excellent color can be easily obtained.
Examples of the oxyacid ions which maybe added to the sulfuric acid electrolytic solution are SeOf", M00 W0 TeOf', CrOfi, ASO33 AsOfl, and V0 Representative metal salts include sulfates, nitrates, phosphates, sulfamates, borates, 'chromates, dichromates, chlorides, silicates and organic acid salts such as oxalates, malonates, tartarates, succinates and the like of nickel cobalt, tin, copper, lead, titanium, cadmium, iron, molybdenum, zirconium and manganese. Prefera ble metal salts are sulfates ofnickel, cobalt, tin, copper, lead, titanium and cadmium.
The amount of the oxyacid anion and/or metal salt to be added depends upon the type of oxyacid and metal salt. In general, the amount is determined by taking into consideration solubility in the sulfuric acid electrolytic solution, coloring property and economy, and usually ranges from about 0.1 to 200 g./l., preferred with from about 1 to 100 g./l. However, when the solubility in the electrolytic solution is too low, the coloring disadvantageously lowered.
The ratio of positive component to negative component in the imperfectly rectified current is at least 2:l. Preferably such ratio is 2-20zl. For the purpose of adjusting the ratio to this range, the current density of the positive component is 0.5 6.0 A/dm with 1.0 3.0 A/dm preferred and that of the negative component is 0.05 6.0 A/dm with 0.1 3.0 A/dm preferred.
When the current density ofthe positive component is lower than the above mentioned range, the anodized film is formed with difficulty and decomposition of the oxyacid and decomposition of sulfuric acid to S are very poor, and thereby coloring, weatherproof prop- The following Examples are given for illustrating the present invention, but should not be construed as restricting the present invention.
EXAMPLE I Sulfuric acid Stannous sulfate 100 g./l. l g./l.
The electrolysis was effected by using a carbon plate as one electrode with imperfectly rectified current, i.e. wherein the positive component has a current density of 2.0 A/dm and the negative component has a current density of 0.2 A/dm for 30 minutes to produce a film of bronze color.
The colored film was treated with boiling water to seal.
EXAMPLE 2 An aluminum plate treated in a way similar to Example 1 above was subjected to electrolysis in an electrolytic bath having the following composition at a bath temperature of 20C.
100 g./l. l0 g./l.
Sulfuric acid Copper sulfate The electrolysis was conducted by using a carbon plate as one electrode with imperfectly rectified current, i.e. wherein the of positive component has the current density of 2.0 A/dm and the negative component has a current density of 0.1 A/dm for 30 minutes to produce a brown film. The resulting colored film was treated with boiling water to seal.
EXAMPLE 3 An aluminum plate treated in a way similar to Example 1 above was subjected to electrolysis in an electrolytic bath having the following composition at a bath temperature of 20C.
200 g./l. 5 g./l.
Sulfuric acid Selenic acid The electrolysis was effected by using a carbon plate as one electrode with imperfectly rectified current, i.e. wherein the positive component has a current density of 3.0 A/dm and the negative component has a current density of 0.2 A/dm for 40 minutes to produce a deep orange film. The resulting colored film was treated with boiling water to seal.
EXAMPLE 4 An aluminum plate treated in a way similar to Example 1 above was subjected to electrolysis in an electrolytic bath having the following composition at a bath temperature of 25C.
Sulfuric acid Sodium stannate 200 g./l. IOU g./l.
The electrolysis was conducted by using a carbon plate as one electrode with imperfectly rectified current, i.e. wherein the positive component has a current density of 3.0 A/dm and the negative component has a current density of 1.2 A/dm' for 30 minutes to produce a grayish film. The resulting colored film was treated with boiling water to seal.
EXAMPLE 5 An aluminum plate treated in a way similar to Example l was subjected to electrolysis in an electrolytic bath having the following composition at a bath temperature of 25C.
220 g./l. l g./l.
Sulfuric acid Sodium tun gstate The electrolysis was conducted by using a carbon plate as one electrode with imperfectly rectified current, i.e. wherein the positive component has a current density of 3.0 A/dm and the negative component has a current density of 1.4 A/dm for 20 minutes to form a grayish film.
The resulting film was treated with boiling water to seal.
EXAMPLE 6 An aluminum plate treated in a way similar to Example l was subjected to electrolysis in an electrolytic bath having the following composition at a bath temperature of 20C.
Sulfuric acid g./l. Stannous sulfate l0 g/l. Selenic acid 5 g./l.
The electrolysis was conducted by using a carbon plate as one electrode with imperfectly rectified current, i.e., wherein the positive component has a current density of 2.5 A/dm and the negative component has a current density of 0.2 A/dm for 30 minutes to produce a film of bronz color. The resulting colored film was treated with boiling water to seal.
EXAMPLE 7 An aluminum plate treated in a way similar to Example l was subjected to electrolysis in an electrolytic bath having the following composition at a bath tem perature of 20C.
Sulfuric acid 100 g./l. Sodium tungstate l g./l. Selenic acid g./l.
The electrolysis was effected by using a carbon plate as one electrode with imperfectly rectified current, i.e. wherein positive component has a current density of 3.0 A/dm and the negative component has a current density of 0.3 A/dm' for 30 minutes to produce a grayish orange film. The resulting colored film was treated with boiling water to seal.
It is believed that the advantages and improved results furnished by the invention will be apparent from the foregoing description. Various modifications and changes may be made without departing from the spirit and scope of the invention as sought to be defined in the following claims.
I claim:
I. A process for coloring an article of aluminum or alloys of aluminum comprising anodizing the article in a sulfuric acid electrolytic solution containing at least one ingredient selected from the group consisting of SeOf", M00 W0 TeOf, CrOf, CrO AsO AsOf, V0 sulfates. nitrates, phosphates, sulfamat es, borates, chromates, dichromates, chlorides, silicates, oxalates, malonates, tartarates, and succinates of nickel, cobalt, tin, copper, lead, titanium, cadmium, iron, molybdenum, zirconium and manganese by subjecting the article to imperfectly rectified current having a ratio of positive component to negative component of at least 2:], the current density of the positive component being approximately 0.5 to 6.0 A/dm and that of the negative component being approximately 0.05 to 6.0 A/dm the amount of the ingredient in the sulfuric acid electrolytic solution being approximately 0.1 to 200 g./l.
2. A process according to claim 1 wherein the ingredient contained in the sulfuricacid electrolytic solution is selected from the group consisting of a sulfate of nickel. cobalt. tin. copper. lead. titanium and cadmium.
3. A process according to claim 1 wherein the amount of the ingredient in the sulfuric acid electrolytic solution is approximately I to g./l.
4. A process according to claim 1 wherein the current density of the positive component is approximately 1.0 to 3.0 A/dm and that of the negative component is approximately 0.1 to 3.0 A/dm 5. A process according to claim 1 wherein the ratio of positive component to negative component is approximately 2-20:l.
6. A process according to claim 5 wherein the ingredient contained in the sulfuric acid electrolytic solution is selected from the group consisting of a sulfate of nickel, cobalt, tin, copper, lead, titanium and cadmium; wherein the amount of the ingredient in the sulfuric acid electrolytic solution is approximately l to 100 g./l.; and wherein the current density of the positive component is approximately 1.0 to 3.0 A/dm and that of the negative component is approximately 0.1 to 3.0 A/dm
Claims (6)
1. A PROCESS FOR COLORING AN ARTICLE OF ALUMINUM OR ALLOYS OF ALUMINUM COMPRISING ANODIZING THE ARTICLE IN A SULFURIC ACID ELECTROLYTIC SOLUTION CONTAINING AT LEAST ONE INGREDIENT SELECTED FROM THE GROUP CONSISTING OF SEO4**2-, MOO4**2-, WO4**2-, TEO4**2-, CRO4**2-, CRO7**2-, ASO3**3-, ASO4**3-, VO4**3-, SULFATES, NITRATES, PHOSPHATES, SULFAMATES, BORATES, CHROMATES, DICHROMATES, CHLORIDES, SILICATES, OXALATES, MALONATES, TARTARATES, AND SUCCINATES OF NICKEL, COBALT, TIN, COPPER, LEAD TITANIUM, CADMIUM, IRON, MOLYBDENUM, ZIRCONIUM AND MANGANESE BY SUBJECTING THE ARTICLE TO IMPERFECTLY RECTIFIED CURRENT HAVING A RATIO OF POSITIVE COMPONENT TO NEGATIVE COMPONENT OF AT LEAST 2:1, THE CURRENT DENSITY OF THE POSITIVE COMPONENT BEING APPROXIMATELY 0.5 TO 6.0 A/DM2 AND THAT OF THE NEGATIVE COMPONENT BEING APPROXIMATELY 0.05 TO 6.0 A/DM2, THE AMOUNT OF THE INGREDIENT IN THE SULFURIC ACID ELECTROLYTIC SOLUTION BEING APPROXIMATELY 0.1 TO 200 G./L.
1. A process for coloring an article of aluminum or alloys of aluminum comprising anodizing the article in a sulfuric acid electrolytic solution containing at least one ingredient selected from the group consisting of SeO42 , MoO42 , WO42 , TeO42 , CrO42 , CrO72 , AsO33 , AsO43 , VO43 , sulfates, nitrates, phosphates, sulfamates, borates, chromates, dichromates, chlorides, silicates, oxalates, malonates, tartarates, and succinates of nickel, cobalt, tin, copper, lead, titanium, cadmium, iron, molybdenum, zirconium and manganese by subjecting the article to imperfectly rectified current having a ratio of positive component to negative component of at least 2:1, the current density of the positive component being approximately 0.5 to 6.0 A/dm2 and that of the negative component being approximately 0.05 to 6.0 A/dm2, the amount of the ingredient in the sulfuric acid electrolytic solution being approximately 0.1 to 200 g./l.
2. A process according to claim 1 wherein the ingredient contained in the sulfuric acid electrolytic solution is selected from the group consisting of a sulfate of nickel, cobalt, tin, copper, lead, titanium and cadmium.
3. A process according to claim 1 wherein the amount of the ingredient in the sulfuric acid electrolytic solution is approximately 1 to 100 g./l.
4. A process according to claim 1 wherein the current density of the positive component is approximately 1.0 to 3.0 A/dm2 and that of the negative component is approximately 0.1 to 3.0 A/dm2.
5. A process according to claim 1 wherein the ratio of positive component to negative component is approximately 2-20:1.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4862172A JPS5315014B2 (en) | 1972-05-18 | 1972-05-18 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3870608A true US3870608A (en) | 1975-03-11 |
Family
ID=12808465
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US359645A Expired - Lifetime US3870608A (en) | 1972-05-18 | 1973-05-14 | Process for coloring aluminum or aluminum alloys by anodizing with imperfectly rectified current |
Country Status (2)
| Country | Link |
|---|---|
| US (1) | US3870608A (en) |
| JP (1) | JPS5315014B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4571287A (en) * | 1980-12-27 | 1986-02-18 | Nagano Prefecture | Electrolytically producing anodic oxidation coat on Al or Al alloy |
| US20070267299A1 (en) * | 2003-01-30 | 2007-11-22 | Yoshiyuki Mitani | Method for Forming Anodic Oxide Layer on Surface of Aluminum or Aluminum Alloy |
| US20130299353A1 (en) * | 2012-05-12 | 2013-11-14 | Catcher Technology Co., Ltd. | Method of forming interference film on surface of aluminum alloy substrate |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5180657A (en) * | 1975-01-11 | 1976-07-14 | Sumitomo Metal Ind | MARUKOZAINOGASUSETSUDANHOHO OYOBI SOCHI |
| JPS5297334A (en) * | 1976-02-13 | 1977-08-16 | Mitsubishi Metal Corp | Device for exfoliating electrodeposited cathode plate in electrolytic refining |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3616311A (en) * | 1964-03-20 | 1971-10-26 | Reynolds Metals Co | Integral hard coat anodizing system |
| US3639221A (en) * | 1969-12-22 | 1972-02-01 | Kaiser Aluminium Chem Corp | Process for integral color anodizing |
-
1972
- 1972-05-18 JP JP4862172A patent/JPS5315014B2/ja not_active Expired
-
1973
- 1973-05-14 US US359645A patent/US3870608A/en not_active Expired - Lifetime
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3616311A (en) * | 1964-03-20 | 1971-10-26 | Reynolds Metals Co | Integral hard coat anodizing system |
| US3639221A (en) * | 1969-12-22 | 1972-02-01 | Kaiser Aluminium Chem Corp | Process for integral color anodizing |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4571287A (en) * | 1980-12-27 | 1986-02-18 | Nagano Prefecture | Electrolytically producing anodic oxidation coat on Al or Al alloy |
| US20070267299A1 (en) * | 2003-01-30 | 2007-11-22 | Yoshiyuki Mitani | Method for Forming Anodic Oxide Layer on Surface of Aluminum or Aluminum Alloy |
| US20130299353A1 (en) * | 2012-05-12 | 2013-11-14 | Catcher Technology Co., Ltd. | Method of forming interference film on surface of aluminum alloy substrate |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5315014B2 (en) | 1978-05-22 |
| JPS4941242A (en) | 1974-04-18 |
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