WO1980000158A1 - Systeme de revetement - Google Patents

Systeme de revetement Download PDF

Info

Publication number
WO1980000158A1
WO1980000158A1 PCT/US1979/000417 US7900417W WO8000158A1 WO 1980000158 A1 WO1980000158 A1 WO 1980000158A1 US 7900417 W US7900417 W US 7900417W WO 8000158 A1 WO8000158 A1 WO 8000158A1
Authority
WO
WIPO (PCT)
Prior art keywords
process according
aluminum
coloring
anodized
acid
Prior art date
Application number
PCT/US1979/000417
Other languages
English (en)
Inventor
G Darrow
A Walsh
Original Assignee
Reynolds Metals Co
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority claimed from US05/972,928 external-priority patent/US4180443A/en
Priority claimed from US06/000,022 external-priority patent/US4179342A/en
Application filed by Reynolds Metals Co filed Critical Reynolds Metals Co
Priority to DE7979900757T priority Critical patent/DE2965186D1/de
Publication of WO1980000158A1 publication Critical patent/WO1980000158A1/fr
Priority to DK81680A priority patent/DK81680A/da

Links

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
    • C25D11/06—Anodisation of aluminium or alloys based thereon characterised by the electrolytes used
    • 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 present invention relates to a process for the production of colored protective coatings on articles of aluminum or aluminum alloys which have been previously anodized in a very special way in order to obtain products which are particularly suitable to be used in architectural applications.
  • both processes produce an anodized layer which is relatively thick (customarily 1.5 mil or heavier) in order to obtain high heat resistance and is of a darkish, muddied color, thereby rendering it unsuitable for use in a process where light, unmuddied colors are desired.
  • U.S. Patent 3,524,799 is directed towards a room temperature process for anodizing aluminum in order to produce hard, dense anodic coatings and the novel process of the present invention utilizes as one step thereof a modification of the process disclosed by this patentee.
  • the specification and claims of this patent are directed to the formation of hard, dense anodic coatings on aluminum or aluminum alloys by anodizing the aluminum in an aqueous electrolyte containing a mineral acid, such as sulfuric acid, a polyhydric alcohol of 3 to 6 carbon atoms, an organic carboxylic acid containing at least one reactive group in the alpha-position to the carboxylic acid group, such as lactic acid or glycine, and an alkali salt of a titanic acid complex of a hydroxyaliphatic carboxylic acid containing from 2 to 8 carbon atoms, such as, for example, titanium dilactate ammonium salt.
  • a mineral acid such as sulfuric acid, a polyhydric alcohol of 3 to 6 carbon atoms
  • a process and bath which demonstrates high throwing power provides uniform color to small creases, cracks, nooks, detents, etc., as well as the larger uniform surfaces of an aluminum or aluminum alloy workpiece being colored.
  • High throwing power also permits the introduction into the coloring bath of a mix of workpieces in terms of their alloy composition and overall physical configuration to obtain uniform color of all such workpieces.
  • prior art coloring techniques it was often difficult, if not impossible, to obtain uniform coloring of workpieces of different alloys or shapes in a single coloring bath at the same time.
  • spacing of the various workpieces in the coloring bath was a critical factor in successfully uniformly coloring aluminum extrusions, particularly for architectural purposes.
  • a novel process for the production of colored coatings on articles of aluminum or aluminum alloys which are particularly adapted to be employed for architectural uses which involves first forming a hard, dense anodic coating on aluminum and aluminum base alloys by anodizing the aluminum in a specific electrolyte comprising sulfuric acid, a polyhydric alcohol of 3 to 6 carbon atoms and an organic carboxylic acid containing at least one reactive group in the alpha position in order to obtain a material having a film thickness of 5-28 microns (0.2 to 1..1 mils) and thereafter electrolytically coloring said anodized aluminum by passing alternating current between said anodized aluminum and a counter-electrode in an aqueous bath containing acid and a metal salt
  • the anodic layer be between about 6 and about 1.1. mils in thickness, as opposed to the 1-5 mils set forth at column 3, line 26 of said U.S. Patent 3,524,799
  • the electrolyte used to anodize the aluminum must be of the type described in U.S. Patent No. 3,524,799 without any alkali salt of titanic acid complex.
  • the combination is an anodizing bath of a polyhydric alcohol containing from 3 to 6 carbon atoms, and an organic carboxylic acid containing a reactive group in alpha-position to the carboxylic acid group will react with the hot reaction products formed during anodizing with or adjacent to the surface of the pore base, and thereby suppress the attack or dissolution of the forming oxide film by these products.
  • the mineral acid component of the electrolyte is sulfuric acid.
  • the anodizing bath concentration of sulfuric acid is generally maintained between about 12% and about 20% by weight, preferably about 15%.
  • Polyhydric alcohols containing from 3 to 6 carbon atoms which may be employed in the practice of the invention, singly or in admixture, include glycerol, butane-diol 1, 4, pentanediol-1, 5, mannitol and sorbitol.
  • the total amount of polyhydric alcohol employed ranges from about 1% to about 4% by volume of the anodizing electrolyte.
  • the preferred polyhydric alcohol is glycerol at a concentration of between about 1% to about 2%.
  • the organic carboxylic acids containing a reactive group in alpha-position to the carboxylic acid group include acids in which the reactive group is hydroxy, amino, keto, or carboxyl.
  • examples of such acids include glycolic (hydroxyacetic), lactic (hydroxypropionic), malic (hydroxysuccinic), oxalic, pyruvic, and aminoacetic acids.
  • Acyclic carboxylic acids such as lactic, malic, and glycolic amino-acetic (glycine) acids are preferred.
  • Glycolic acid is specifically preferred in combination with glycerol.
  • a mixture of two or more of these acids may be employed in combination with the mineral acid and the polyhydric alcohol.
  • the amount of carboxylic acid included in the electrolyte is preferably between about 1% and about 4% by volume of the bath.
  • a preferred concentration when glycolic acid is used in combination with glycerol is between about 1 and 2% by volume.
  • the temperature at which anodizing is carried out must range from 18 to 30°C (65.-85° ⁇ 0 with room temperature condition, i.e., 68-75°, F, being preferred.
  • the current density which is used in the anodizing operation be in the range of from about 24 to about 36 amperes/sq. ft. (2.6 to 3.9A/dm 2 ) .
  • the time required to achieve the desired film thickness of between about 0.2 and 1.1 mils will vary with the other parameters of temperature, current density, chemical composition of the bath, etc., but generally anodizing times on the order of from about 8 to about 30 minutes produce acceptable results.
  • the aluminum article is thereafter colored electrolytically by passing alternating current between said article and a counterelectrode an aqueous acidic solution containing a water soluble metal salt.
  • the electrolytic coloring process is extremely well known in the art, and in this connection, is disclosed in the technical and patent literature, including U.S. Patent 3,669,856; 3,849,263 and 3,869,180; the disclosure of which is herein incorporated by reference.
  • the preferred metallic salt is a salt of tin, although salts of nickel, cobalt, copper and silicomolybdic acid and silicotungstic acid can also be employed, individually or in combination.
  • the salts of these metals could be formed by adding the metal to the sulfuric acid in. the bath, but, preferably a sulfate salt of the metal is added to the bath for better control of the amount of the metal in solution in the electrolyte.
  • the metallic salts desired to provide the particular color can be utilized at a concentration of from 0.5 to 20% by weight, preferably about 2% by weight based on the electrolyte.
  • the salts modify the pH of the electrolyte to which they are added, and the pH of the complete bath may ordinarily range from about 3.5 to 5.
  • the pH may be as low as 1, preferably 1.5. Tin in the preferred metalibr the salt because of the high throwing power of the bath and resultant improved colour effects at such low pH values.
  • the alternating current may have a frequency of 10-
  • the counterelectrode which is employed is preferably made out of the same metal as the metal used in the electrolyte solution.
  • the counterelectrode be made out of tin.
  • counterelectrodes made of other materials, such as graphite, stainless steel or titanium can also be used.
  • Another advantage of the novel process of this invention resides in the fact that it is possible to correct for too dark a color electrolytically which has heretofore been impossible with processes utilizing dyesor with processes involving simultaneous anodizing and coloring. According to this technique, after appliccation of an excess of color the polarity of the coloring system is reversed and color can be subtracted from the anodized layer.
  • the electrolytic coloring process is carried out by passing an alternating current between the anodized article of aluminum or aluminum alloy which has been carried out in the manner above-described, and a counterelectrode immersed in an acid aqueous bath containing metal salts having coloring cations, wherein the colored tones of the coatings can be controlled in a simple manner by modulating the shape of the curve of the applied alternating voltage in such a manner that during the coloring process the alternating voltage will provide a suitable ratio between the two current directions for an advantageous transport of material and course of reaction with regard to said anodized aluminum article.
  • the alternating voltage supplied is modulated as regarding its amplitude and/or frequency so as to make asymmetrical, thereby to control the color tone of the aluminum article.
  • the modulation of the alternating- voltage can be carried out in several ways, such as simultaneously supplying two or more different alternating voltages or a superimposed direct voltage or by generating an alternating voltage having the desired frequency and curve shape.
  • the material for the counterelectrodes can be stainless steel, titanium, copper, nickel, but preferably tin because they lead to advantageously low energy consumption.
  • the strength of the alternating voltage in the modulation of the amplitude and/or frequency thereof according to the present process is from 5-50 volts, depending upon the composition of the electrolyte and the properties of the oxide layer previously formed.
  • a current density of from 0.1 to 0.5 A/dm 2 , dependent on the electrolyte employed and a low treatment period of from 1 to 10 minutes.
  • various soluble metallic salts can be employed.
  • the preferred salts are those of tin, although salts of nickel, cobalt, copper, silicomolybdic acid and silicotungstic acid can also be employed.
  • the electrolytic coloring bath also contains a strong acid which is desirably either sulfuric or hydrochloric.
  • the metallic salts . e.g., sulfates, chlorides, acetates, etc. desired to provide the particular color can be utilized at a concentration of from 0.5 to 20% by weight, preferably about 2% by weight based on the electrolyte.
  • the pH of the electrolyte may vary considerably within the acid range, but pHs of about 1.5 have been found to be useful.
  • a particularly preferred embodiment resides in having present in the electrolyte a certain amount of aluminum.
  • the aluminum can be provided by the addition of suitable aluminum compounds, such as aluminum sulfate or a certain part of a previously used electrolytic bath can also be used.
  • suitable aluminum compounds such as aluminum sulfate or a certain part of a previously used electrolytic bath can also be used.
  • the amount of aluminum which is present in the electro- lyte can range from 0-12 grams/liter, and more desirably, from 4-8 grams/liter.
  • novel process of this invention is applicable to color articles made from aluminum, as well as from aluminum base alloys of all kinds.
  • the coloring takes place faster, more efficiently if the alternating current is regulated relatively slowly of the order of a few seconds from 0 to the voltage which is desired for the coloring. This relates toboth the starting up of the coloring and to a latter supply of another alternating voltage than the one initially used.
  • An aluminum article is anodized for about 24 minutes at 65°F in an anodizing bath at 1.5 pH and having the following composition:
  • Example 2 The process of Example 1 is repeated with the exception that a deep red to black color is obtained, depending on duration, using copper sulfate instead of tin sulfate, a pH of 4.0 and a counterelectrode of graphite.
  • Example 3 The process of Example 2 is repeated with the exception that bronze tones to black are obtained using cobalt sulfate as the salt.
  • Example 2 The process of Example 2 is repeated with the exception that bronze tones are obtained using nickel sulfate as the salt and a counterelectrode of nickel.
  • EXAMPLE 5 An aluminum article was anodized in accordance with normal anodizing techniques utilizing a current density of 24 amperes/sq. ft. and an electrolytic bath comprising 20 weight percent surfuric acid, and 8 grams/liter of oxalic acid. The temperature utilize ranged from 18-21°C, and the resulting aluminum article had an anodized layer of 25 microns. The results product was not suitable for coloring due to the fact that it was darkish in color.
  • EXAMPLE 6 An aluminum article was anodized using a solution comprising 18 weight percent sulfuric acid, 1% glycolic acid and 1% glycerol. The anodizing was carried out at a current density of 36 amperes/sq. ft. at a temperature of about 19.5°C. After 13 minutes an anodized layer of approximately 0.83 mils was obtained.
  • the anodized aluminum article was then electrolytically colored by immersing the same into a bath comprising 25 grams/liter sulfuric acid, 22 grams/liter sulfonic acid, 25 grams/liter tin sulfate, 5 grams/liter aluminum sulfate, 0.2 grams/liter of 8- naphthol and 0.4 grams of gelatin per liter.
  • the electrolytic coloring was carried out by applying alternating current through the electrolyte at a voltage of 8 volts for three minutes. Three minutes of alternating current of half-wave was then applied. An aluminum article having a blackish color was obtained.
  • EXAMPLE 7 An aluminum article was anodized utilizing the electrolyte solution of Example 2 at a current density of -40 amperes/sq. ft. at a temperature of 20°C.
  • the anodized article which was obtained was thereafter electrolytically colored in accordance with the techniques of United States 3,669,856. This resulted in an article having poor color.
  • EXAMPLE 8 An aluminum article was anodized utilizing the anodixing solution set forth in Example 2 at a temperature of 20°C and at a current density of 48. amperes/sq. ft. The anodizing was carried out until an anodized layer was obtained which had a thickness of about 1.65 mils. Subsequent color anodizing of this material in accordance with the techniques of this invention resulted in spalling on the anodic film.
  • EXAMPLE 9 An aluminum article was anodized utilizing the electrolyte solution of Example 2 at a temperature of 21°C until an anodized layer having a thickness of about 8 mils was obtained.
  • This material was then electrolytically colored utilizing the techniques Of United States 3,669,856 and the color solution of Example 2. Alternating current was applied for 1 1/2 minutes and thereafter a half-wave alternating current was applied for a half-minute. The resulting material was colored satisfactorily and was capable for use as an architectural material.
  • An aluminum article was anodized using the electrolytic solution of Example 2 at a temperature of 20°C for six minutes in order to obtain an article which had a thickness of approximately 0.4 mils.
  • This material was then electrolytically colored utilizing the solution of Example 2 by passing normal AC current between the aluminum article and a counter- electrode for two minutes, thereafter an alternating current having a minus half-wave which was asymmetrical was applied for one minute.
  • Example 12 An aluminum article was anodized utilizing the solution of Example 2 at a temperature of 20°C, a current density of 36 amperes/sq. ft. in order to obtain a material which had a thickness of 1.1 mils. The material was thereafter color anodized utilizing the tin solution set forth in Example 2 and the technique of United States 3,669,856. Alternating current was applied for 1 1/2 minutes followed by half-wave at one minute. A perfectly acceptable colored article was obtained. EXAMPLE 12
  • Example 5 The process of Example 5 is repeated with the exception that after the product was run to a bronze color, it was immersed in an oxidizing acid, preferably 20-30 volume % nitric acid at room temperature, which resulted in a uniform champagne color. This color is virtually impossible to produce in a uniform manner by any other known process.
  • an oxidizing acid preferably 20-30 volume % nitric acid at room temperature

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Electroplating And Plating Baths Therefor (AREA)
  • Other Surface Treatments For Metallic Materials (AREA)
  • Application Of Or Painting With Fluid Materials (AREA)

Abstract

Un procede de production de revetement en couleur sur des articles en aluminium ou en alliage d'aluminium, adapte particulierement pour etre utilise dans le domaine de l'architecture, consiste en premier lieu a former un revetement anodique dur et dense sur de l'aluminium ou des alliages d'aluminium par oxydation anodique de l'aluminium dans un electrolyte comprenant de l'acide sulfurique, un alcool polyhydrique de 3 a 6 atomes de carbone et un acide de carboxylique organique contenant au moins un groupe reactif dans la position alpha de maniere a obtenir une pellicule d'un materiau d'une epaisseur de 5 a 28 microns puis a colorer par voie electrolitique ledit aluminium oxyde anodiquement en faisant passer un courant alternatif entre ledit aluminium anodise et une contre-electrode dans un bain aqueux contenant de l'acide et un sel metallique. La tension peut etre modulee de l'exterieur du systeme a electrode de maniere a appliquer sur les electrode une tension avec asymetrie commandees.
PCT/US1979/000417 1978-06-28 1979-06-14 Systeme de revetement WO1980000158A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
DE7979900757T DE2965186D1 (en) 1978-06-28 1979-06-14 Coating system
DK81680A DK81680A (da) 1978-06-28 1980-02-26 Fremgangsmaade til fremstilling af farvede beskyttelsesovertraek paa aluminiumgenstande

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
US92005778A 1978-06-28 1978-06-28
US92005378A 1978-06-28 1978-06-28
US05/972,928 US4180443A (en) 1978-06-28 1978-12-26 Method for coloring aluminum
US06/000,022 US4179342A (en) 1978-06-28 1979-01-02 Coating system method for coloring aluminum
US920053 1997-08-28

Publications (1)

Publication Number Publication Date
WO1980000158A1 true WO1980000158A1 (fr) 1980-02-07

Family

ID=27484965

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1979/000417 WO1980000158A1 (fr) 1978-06-28 1979-06-14 Systeme de revetement

Country Status (10)

Country Link
EP (1) EP0015279B1 (fr)
JP (1) JPS55500501A (fr)
AR (1) AR222177A1 (fr)
BE (1) BE877340A (fr)
DE (1) DE2965186D1 (fr)
DK (1) DK81680A (fr)
ES (1) ES482021A1 (fr)
IT (1) IT1125392B (fr)
NL (1) NL7905049A (fr)
WO (1) WO1980000158A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0163786A1 (fr) * 1980-11-24 1985-12-11 Jack L. Woods Méthode de reproduction sur aluminium d'images de toutes couleurs
CN111876812A (zh) * 2020-08-01 2020-11-03 东莞市慧泽凌化工科技有限公司 一种无镍电解着色增黑添加剂及其使用方法

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ES2037578B1 (es) * 1991-04-10 1994-02-01 Novamax Technologies Holding I Metodo para la obtencion, por via electronica, sobre aluminio anodizado, de una gama de colores grises.
JP4660760B2 (ja) * 2005-06-02 2011-03-30 国立大学法人広島大学 アルミニウム又は／及びアルミニウム合金の陽極酸化皮膜の形成方法およびその方法により形成される陽極酸化皮膜
DK2665842T3 (en) * 2011-01-17 2015-03-23 Hydro Aluminium Rolled Prod Exterior facade metal plate made of aluminum with a high surface roughness

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3524799A (en) * 1969-06-13 1970-08-18 Reynolds Metals Co Anodizing aluminum
US3669856A (en) * 1968-06-21 1972-06-13 Ove Christopher Gedde Process for the production of colored protective coatings on articles of aluminum or aluminum alloys
US3769180A (en) * 1971-12-29 1973-10-30 O Gedde Process for electrolytically coloring previously anodized aluminum using alternating current
US3849263A (en) * 1969-06-25 1974-11-19 O Gedde Process for electrolytically colouring of aluminium which has previously been anodically oxidized
US3915813A (en) * 1972-11-21 1975-10-28 Showa Aluminium Co Ltd Method for electrolytically coloring aluminum articles

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3669856A (en) * 1968-06-21 1972-06-13 Ove Christopher Gedde Process for the production of colored protective coatings on articles of aluminum or aluminum alloys
US3524799A (en) * 1969-06-13 1970-08-18 Reynolds Metals Co Anodizing aluminum
US3849263A (en) * 1969-06-25 1974-11-19 O Gedde Process for electrolytically colouring of aluminium which has previously been anodically oxidized
US3769180A (en) * 1971-12-29 1973-10-30 O Gedde Process for electrolytically coloring previously anodized aluminum using alternating current
US3915813A (en) * 1972-11-21 1975-10-28 Showa Aluminium Co Ltd Method for electrolytically coloring aluminum articles

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0163786A1 (fr) * 1980-11-24 1985-12-11 Jack L. Woods Méthode de reproduction sur aluminium d'images de toutes couleurs
CN111876812A (zh) * 2020-08-01 2020-11-03 东莞市慧泽凌化工科技有限公司 一种无镍电解着色增黑添加剂及其使用方法
CN111876812B (zh) * 2020-08-01 2021-11-05 东莞市慧泽凌化工科技有限公司 一种无镍电解着色增黑添加剂及其使用方法

Also Published As

Publication number Publication date
DE2965186D1 (en) 1983-05-19
IT1125392B (it) 1986-05-14
IT7923954A0 (it) 1979-06-28
EP0015279A4 (fr) 1980-10-16
ES482021A1 (es) 1980-02-16
BE877340A (fr) 1979-10-15
DK81680A (da) 1980-02-26
EP0015279A1 (fr) 1980-09-17
EP0015279B1 (fr) 1983-04-13
NL7905049A (nl) 1980-01-03
JPS55500501A (fr) 1980-08-07
AR222177A1 (es) 1981-04-30

Similar Documents

Publication Publication Date Title
US4681668A (en) Anodic aluminium oxide film and method of forming it
CA1054089A (fr) Procede de coloration de l'aluminium et de ses alliages par electrolyse
US4180443A (en) Method for coloring aluminum
US4179342A (en) Coating system method for coloring aluminum
EP0015279B1 (fr) Systeme de revetement
US3989605A (en) Method for continuous electrolytic coloring of aluminum articles
CA1061280A (fr) Methode pour produire une pellicule d'oxyde anodique de couleur verte sur des elements en aluminium ou en alliage a base d'aluminium
US4002549A (en) Apparatus and method for continuous electrolytic coloring of aluminum articles
JPS63312998A (ja) 陽極酸化アルミニウムの電解着色
US3704210A (en) Process for coloring aluminum objects
CA1153980A (fr) Methode de production d'articles en aluminium a surface anodisee teintee
JP4253716B2 (ja) マグネシウム材料製品の表面処理方法
CA1155080A (fr) Anodisation asymetrique de l'aluminium dans l'acide sulfurique, les alcools polyhydriques et les acides carboxyliques
CA1148110A (fr) Coloration de l'aluminium apres anodisation dans des solutions electrolytiques d'acide sulfurique, d'alcool polyhydrique et d'acide carboxylique
JPS5839237B2 (ja) 陽極酸化されたアルミニウムの電解着色法
JPS58147592A (ja) アルミニウム又はアルミニウム合金の着色方法
US2827425A (en) Method of forming protective coatings on iron articles
JP2953474B2 (ja) アルミニウムおよびアルミニウム合金の電解処理方法
EP0936288A2 (fr) Procédé pour produire des variations de couleur sur de l'aluminium anodisé et pigmenté par voie électrolytique
US3912602A (en) Process for colouring aluminum electrolytically
JP2908105B2 (ja) アルミニウム又はアルミニウム合金の電解着色法
US3658665A (en) Electrolytic method for producing a colored anodized layer on aluminum and alloys of aluminum
JPH10265996A (ja) アルミニウムまたはその合金のアルカリ耐食性の良好な陽極酸化処理方法
Zemanová et al. A new approach to nickel electrolytic colouring of anodised aluminium
JPS5912758B2 (ja) 着色軽金属材の製造方法

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): BR DK JP

Designated state(s): BR DK JP

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): CH DE FR GB SE

Designated state(s): CH DE FR GB SE