US2233785A - Process for the manufacture of oxide layers on aluminum and aluminum alloys and to electrolytes therefor - Google Patents
Process for the manufacture of oxide layers on aluminum and aluminum alloys and to electrolytes therefor Download PDFInfo
- Publication number
- US2233785A US2233785A US114644A US11464436A US2233785A US 2233785 A US2233785 A US 2233785A US 114644 A US114644 A US 114644A US 11464436 A US11464436 A US 11464436A US 2233785 A US2233785 A US 2233785A
- Authority
- US
- United States
- Prior art keywords
- aluminum
- acid
- alloys
- sulphuric acid
- bath
- 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 description 34
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 title description 33
- 239000003792 electrolyte Substances 0.000 title description 24
- 238000000034 method Methods 0.000 title description 17
- 238000004519 manufacturing process Methods 0.000 title description 8
- 229910000838 Al alloy Inorganic materials 0.000 title description 5
- 230000008569 process Effects 0.000 title description 4
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 32
- 230000003647 oxidation Effects 0.000 description 30
- 238000007254 oxidation reaction Methods 0.000 description 30
- 239000001117 sulphuric acid Substances 0.000 description 30
- 235000011149 sulphuric acid Nutrition 0.000 description 30
- 239000002253 acid Substances 0.000 description 29
- 239000010410 layer Substances 0.000 description 29
- 150000007513 acids Chemical class 0.000 description 20
- 229910045601 alloy Inorganic materials 0.000 description 19
- 239000000956 alloy Substances 0.000 description 19
- 239000007864 aqueous solution Substances 0.000 description 14
- BDHFUVZGWQCTTF-UHFFFAOYSA-N sulfonic acid Chemical compound OS(=O)=O BDHFUVZGWQCTTF-UHFFFAOYSA-N 0.000 description 14
- 238000007792 addition Methods 0.000 description 13
- 239000000243 solution Substances 0.000 description 13
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 10
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 9
- 230000015572 biosynthetic process Effects 0.000 description 9
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 9
- 125000004356 hydroxy functional group Chemical group O* 0.000 description 9
- 230000001681 protective effect Effects 0.000 description 9
- 229910021653 sulphate ion Inorganic materials 0.000 description 9
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 8
- 229940037395 electrolytes Drugs 0.000 description 8
- MGSRCZKZVOBKFT-UHFFFAOYSA-N thymol Chemical compound CC(C)C1=CC=C(C)C=C1O MGSRCZKZVOBKFT-UHFFFAOYSA-N 0.000 description 8
- IULJSGIJJZZUMF-UHFFFAOYSA-N 2-hydroxybenzenesulfonic acid Chemical compound OC1=CC=CC=C1S(O)(=O)=O IULJSGIJJZZUMF-UHFFFAOYSA-N 0.000 description 7
- 150000001491 aromatic compounds Chemical class 0.000 description 7
- 229910052751 metal Inorganic materials 0.000 description 7
- 239000002184 metal Substances 0.000 description 7
- 125000004043 oxo group Chemical group O=* 0.000 description 7
- 239000000203 mixture Substances 0.000 description 5
- 125000001424 substituent group Chemical group 0.000 description 5
- CSNNHWWHGAXBCP-UHFFFAOYSA-L Magnesium sulfate Chemical compound [Mg+2].[O-][S+2]([O-])([O-])[O-] CSNNHWWHGAXBCP-UHFFFAOYSA-L 0.000 description 4
- 239000005844 Thymol Substances 0.000 description 4
- 150000001875 compounds Chemical class 0.000 description 4
- -1 sulphate ions Chemical class 0.000 description 4
- 229960000790 thymol Drugs 0.000 description 4
- 230000008859 change Effects 0.000 description 3
- CYGSXDXRHXMAOV-UHFFFAOYSA-N o-cresol hydrogen sulfate Chemical compound CC1=CC=CC=C1OS(O)(=O)=O CYGSXDXRHXMAOV-UHFFFAOYSA-N 0.000 description 3
- 235000006408 oxalic acid Nutrition 0.000 description 3
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 2
- 230000004075 alteration Effects 0.000 description 2
- GRWVQDDAKZFPFI-UHFFFAOYSA-H chromium(III) sulfate Chemical compound [Cr+3].[Cr+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O GRWVQDDAKZFPFI-UHFFFAOYSA-H 0.000 description 2
- 239000011696 chromium(III) sulphate Substances 0.000 description 2
- 235000015217 chromium(III) sulphate Nutrition 0.000 description 2
- 150000001896 cresols Chemical class 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 229910052943 magnesium sulfate Inorganic materials 0.000 description 2
- 235000019341 magnesium sulphate Nutrition 0.000 description 2
- 239000011702 manganese sulphate Substances 0.000 description 2
- 235000007079 manganese sulphate Nutrition 0.000 description 2
- SQQMAOCOWKFBNP-UHFFFAOYSA-L manganese(II) sulfate Chemical compound [Mn+2].[O-]S([O-])(=O)=O SQQMAOCOWKFBNP-UHFFFAOYSA-L 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- NWTKQZYHPISKGV-UHFFFAOYSA-N 1-hydroxy-2-methylcyclohexa-3,5-diene-1,3-disulfonic acid Chemical compound C1(C(=CC=CC1(O)S(=O)(=O)O)S(=O)(=O)O)C NWTKQZYHPISKGV-UHFFFAOYSA-N 0.000 description 1
- KJCVRFUGPWSIIH-UHFFFAOYSA-N 1-naphthol Chemical compound C1=CC=C2C(O)=CC=CC2=C1 KJCVRFUGPWSIIH-UHFFFAOYSA-N 0.000 description 1
- QTWJRLJHJPIABL-UHFFFAOYSA-N 2-methylphenol;3-methylphenol;4-methylphenol Chemical compound CC1=CC=C(O)C=C1.CC1=CC=CC(O)=C1.CC1=CC=CC=C1O QTWJRLJHJPIABL-UHFFFAOYSA-N 0.000 description 1
- ZMPRRFPMMJQXPP-UHFFFAOYSA-N 2-sulfobenzoic acid Chemical class OC(=O)C1=CC=CC=C1S(O)(=O)=O ZMPRRFPMMJQXPP-UHFFFAOYSA-N 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- 229910052936 alkali metal sulfate Inorganic materials 0.000 description 1
- 150000001340 alkali metals Chemical class 0.000 description 1
- 150000004945 aromatic hydrocarbons Chemical class 0.000 description 1
- 125000003118 aryl group Chemical group 0.000 description 1
- 150000004649 carbonic acid derivatives Chemical class 0.000 description 1
- 125000002915 carbonyl group Chemical group [*:2]C([*:1])=O 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- KRVSOGSZCMJSLX-UHFFFAOYSA-L chromic acid Substances O[Cr](O)(=O)=O KRVSOGSZCMJSLX-UHFFFAOYSA-L 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 229930003836 cresol Natural products 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000010494 dissociation reaction Methods 0.000 description 1
- 230000005593 dissociations Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- AWJWCTOOIBYHON-UHFFFAOYSA-N furo[3,4-b]pyrazine-5,7-dione Chemical compound C1=CN=C2C(=O)OC(=O)C2=N1 AWJWCTOOIBYHON-UHFFFAOYSA-N 0.000 description 1
- ZLNQQNXFFQJAID-UHFFFAOYSA-L magnesium carbonate Chemical compound [Mg+2].[O-]C([O-])=O ZLNQQNXFFQJAID-UHFFFAOYSA-L 0.000 description 1
- 239000001095 magnesium carbonate Substances 0.000 description 1
- 229910000021 magnesium carbonate Inorganic materials 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 239000011572 manganese Substances 0.000 description 1
- 239000011241 protective layer Substances 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 125000001273 sulfonato group Chemical group [O-]S(*)(=O)=O 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
- C25D11/06—Anodisation of aluminium or alloys based thereon characterised by the electrolytes used
- C25D11/10—Anodisation of aluminium or alloys based thereon characterised by the electrolytes used containing organic acids
Definitions
- Patented 4 1941 PROCESS FOR THE MANUFACTURE OF OXIDE LAYERS N ALUMINUM AND ALUMINUM ALLOYS AND TO ELECTRO- LYTES THEREFOR Joachim Korpiun, Berlin-Grunewald, Germany, assignor, by mesne assignments, to
- This invention relates to' -a process 'for the manufacture of oxide layers 'on aluminum and' aluminum alloys and to electrolytes therefor.
- the processof this invention comprises the application of electrolytes which contain hydroxy or 0x0 sulphonic acids or sulphonic acids containing carbonyl groups, as, for example, the carboxylgroup, in particular of aromatic nature, alone or with the addition of small quantities of sulphuric acid or sulphates.
- the polysulphonic acids as, for example, the disulphonic acids possess advantages compared with the monosulphonic acids, since in. the case of the former higher current densities can be employed.
- the electrolytes for the purpose of obtaining very hard oxide layers according to the invention should contain relatively small quantities of sulphuric acid. It is to be recommended therefore in manufacture on a commercial scale to employ crude sulphonic acids which are available containing an excess of sulphuric acid the removal of which from the sulphonation product is not necessary, that is to say thereforethat for the manufacture of hard oxide layers the crude sulphonation mixture can be employed insofar as its content of free sulphuric acid falls within the stated limits.
- this disadvantage can be removed when the sulphuric acid is advantageously replaced by sulphates, in which case within wide limits a change 'of the concentration of the added sulphate does not affect the method of working of the bath.
- 35- all sulphates can be employed which are soluble in the solutions of the sulphonic acids and do not enter into any-reactions with these which alter the composition.
- the properties of the lay-. .40 ers obtained in the'anodic oxidation can be influenced to a far reaching extent.
- the sulphates of the alkali metals give 1 .lifi sulphonic acids certain quantities of sulphuric acid are always contained, the removal of which would render necessary particular'working operations, this I excess sulphuric acid can be em-- ployed for the formation of the desired sulphate.
- Example 1 As electrolyte for the oxidation of aluminum is employed a solution of cresolsulphonic acid place with an alternating current of 40-50 volts at a bath temperature of about 25 C. Light c01- ored layers of medium hardness are obtained.
- Example 2 The oxidation of the aluminum or its alloys .takes place in the solution of a crude phenol sulphonic acid (sulphonation mixture), whichstill contains about 5% by weight of free sulphuric acid. The density of the acid solution amounts to about 1.2. With the application of alternating current and a potential of 26 volts in this electrolyte very hard oxide layers are obtained.
- Example 4 As electrolyte for the oxidation of aluminum is employed m-cresoldisulphonicacid (cryst.) in a quantity of 300 grams per litre of bath liquid, which'in addition contains 2% of sulphuric acid. Working is conducted with potentials of 15-40 volts according to the alloy employed. 40
- ther can also be employed an addition of 5% magnesium sulphate;
- the layers thus obtained on the aluminum are somewhat harder than by the application ofthe monosulphonic acid.
- Example 5 An electrolyte suitable for the electrolytic oxidation of aluminum and the like is obtained by treating a solution of 350 grams of pure thymol sulphonic acid per litre with 90 grams of man ganese sulphate. The addition of,sulphate can be increased up to 180 grams without the layers I obtained in the oxidation being essentially difierent. With higher content of manganese sulphate g on the other,hand with certain aluminum alloys a slow reduction ofth'e wearing capacity of the layers takes place.
- Example 6 In a solution of commercial phenolsulphonic acid which contains per litre 250 grams of phenol sulphonic acid and 24 grams of sulphuric acid, the sulphuric acid is neutralised with 25 grams of magnesium carbonate and the, sulphate content of the solution is increased by thefurther addition of 50 grams of magnesium sulphate. With such an electrolyte are obtained commercially valuable oxide layers on light metal which are of practically the same quality when the mag- 0 nesium sulphate content is further increased to 100 grams. 1
- Example 7 In a solution which contains'pcr litre 400 grams of cresolsulphonic acid and38 grams of sulphuric acid, by the addition of 160 grams of the chromic salt of cresolsulphonic acid the free sulphuric acid is converted into chromic sulphate. After the addition of a further 20-80 grams of chromic sulphate a bath is obtained the method of working of which in the anodic oxidation is practically independent of the sulphate content.
- the oxide layers thus obtained can in the known manner be colored, consolidated and impregnated.
- a method for the electrolytic formation of oxide protective films on aluminum and alloys thereof which comprises subjecting the same to anodic oxidation in a bath consisting essentially of anaqueous solution of a sulphonic acid of an aromatic compound containing at least one sub- .stitu'ent taken from the class consisting of hydroxy, oxo and carboxyl.
- a method for the electrolytic formation of oxide protective films on aluminum and alloys thereof which comprises subjecting the same to anodic oxidation in a .bath consisting essentially of an aqueous solution of a sulphonic acid of an aromatic compound containing at least one substituenttaken from the class consisting of hydroxy, oxo and carboxyl, said acid having a dissociation constant greater than 1x 10* to 1 x 10 3.
- a method for the electrolytic formation of oxide protective films on aluminum and alloys thereof which comprises subjecting the same to anodic oxidation in a bath consisting essentially of an aqueous solution of a phenol sulphonic acid.
- a method for the electrolytic isrmation of oxide protective films on aluminum and alloys thereof which comprises subjecting the same to anodic oxidation in a bath consisting essentially of an aqueous solution of a phenol sulphonic acid taken from the class consisting of phenol,
- An electrolyte for the anodic oxidation of oxide protective films on aluminum and alloys thereof which comprises subjecting the same to anodic oxidation in a bath consisting essentially of an aqueous solution of a cresol disulphonic acid.
- a method for the electrolytic formation of oxide protective films on aluminum and alloys thereof which comprises subjecting the same to anodic oxidation in a bath consisting essentially of an aqueous solution of a sulphonic acid of an aromatic compound containing at least one substituent taken from the class consisting of hydroxy, oxo and carboxyl, said bath containing a minor amount of a compound taken from the class of sulphuric acid, alkaliv metal sulphates and sulphate's of polyvalent kations.
- a method for theelectrolytic formation of oxide protective films On aluminum and alloys thereof which comprises subjecting the same to anodic oxidation in a bath consisting essentially of an aqueous solution of a sulphonic acid of an aromatic compound containing at least one substituent taken from the class consisting of hydroxy, oxo and carboxyl, said bath containing an amount of sulphuric acid 'up to 10% by weight of said sulphonic acid.
- a method for the electrolytic formation of oxide'protective films' on aluminum and alloys thereof which comprises subjecting the same to anodic oxidation in a bath consisting essentially of an aqueous solution of a sulphonic acid of "an aromatic compound containing at least one substituent taken from the class consisting of hydroxy, oxo and carboxyl, said bath containing a minor amount of a sulphate taken from Mn, Cr and Al.
- aluminum and alloys thereof consisting essentially of an aqueous solution of a sulphonic acid of an aromatic compound containing at least one substituent taken from the class consisting of hydroxy, oxo and carboxy.
- An electrolyte for the anodic oxidation of aluminum and alloys thereof consisting essentially of an aqueous solution of a phenol sulphonic acid.
- An electrolyte for the anodic oxidation of aluminum and alloys thereof consisting essentially of an aqueous solution of a disulphonic acid of an aromatic hydroxy compound.
- An electrolyte for the anodic oxidation of aluminum and alloys thereof consisting'essentially of an aqueous solution of a phenolsulphonic acid taken from the class consisting of phenol, cresols and thymol. 14.
- An electrolyte for the anodic oxidation of aluminum and alloys thereof consisting essentially of an aqueous solution of a cresolidisuh phonic acid.
- An electrolyte for the anodic oxidation of aluminum and alloys thereof consisting essentially of an aqueous solution of a sulphonic acid of an aromatic compound containing at least one substituent taken from the class consisting of hydroxy, oxo and carboxy, said solution containing a minor amount of a compound taken from the class of sulphuric acid, alkali metal sulphates and sulphates of polyvalent kations.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Electrolytic Production Of Non-Metals, Compounds, Apparatuses Therefor (AREA)
- Printing Plates And Materials Therefor (AREA)
- Preventing Corrosion Or Incrustation Of Metals (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE206445X | 1935-12-11 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2233785A true US2233785A (en) | 1941-03-04 |
Family
ID=5792568
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US114644A Expired - Lifetime US2233785A (en) | 1935-12-11 | 1936-12-07 | Process for the manufacture of oxide layers on aluminum and aluminum alloys and to electrolytes therefor |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US2233785A (en(2012)) |
| CH (1) | CH206445A (en(2012)) |
| ES (1) | ES152467A1 (en(2012)) |
| FR (1) | FR814798A (en(2012)) |
| GB (1) | GB474323A (en(2012)) |
| NL (1) | NL48557C (en(2012)) |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2541083A (en) * | 1945-08-25 | 1951-02-13 | Sperry Corp | Electroplating on aluminum |
| US2855351A (en) * | 1954-09-20 | 1958-10-07 | Sanford Process Co Inc | Process for electrolytically producing oxide coating on aluminum and aluminum alloys |
| US2855350A (en) * | 1954-09-20 | 1958-10-07 | Sanford Process Co Inc | Process for electrolytically producing oxide coating on aluminum and aluminum alloys |
| US2998361A (en) * | 1958-06-11 | 1961-08-29 | Toyo Kohan Co Ltd | Electrochemical treatment of metal surfaces and the products thereof |
| US3031387A (en) * | 1958-04-14 | 1962-04-24 | Kaiser Aluminium Chem Corp | Anodic oxidation of aluminum |
| US3143485A (en) * | 1961-11-28 | 1964-08-04 | Aluminum Co Of America | Aluminum anodizing |
| US3227639A (en) * | 1961-10-24 | 1966-01-04 | Aluminum Co Of America | Method of anodizing aluminum with electrolyte containing sulfophthalic acid |
| US3280013A (en) * | 1964-06-02 | 1966-10-18 | Aluminum Co Of America | Anodizing electrolyte and process |
| US3486991A (en) * | 1965-12-27 | 1969-12-30 | Sumitomo Chemical Co | Method of producing a colored anodic oxide film on aluminum |
| US3658665A (en) * | 1966-07-13 | 1972-04-25 | Pechiney Prod Chimiques Sa | Electrolytic method for producing a colored anodized layer on aluminum and alloys of aluminum |
-
0
- NL NL48557D patent/NL48557C/xx active
-
1936
- 1936-12-07 US US114644A patent/US2233785A/en not_active Expired - Lifetime
- 1936-12-09 GB GB33848/36A patent/GB474323A/en not_active Expired
- 1936-12-10 CH CH206445D patent/CH206445A/de unknown
- 1936-12-11 FR FR814798D patent/FR814798A/fr not_active Expired
-
1941
- 1941-04-15 ES ES0152467A patent/ES152467A1/es not_active Expired
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2541083A (en) * | 1945-08-25 | 1951-02-13 | Sperry Corp | Electroplating on aluminum |
| US2855351A (en) * | 1954-09-20 | 1958-10-07 | Sanford Process Co Inc | Process for electrolytically producing oxide coating on aluminum and aluminum alloys |
| US2855350A (en) * | 1954-09-20 | 1958-10-07 | Sanford Process Co Inc | Process for electrolytically producing oxide coating on aluminum and aluminum alloys |
| US3031387A (en) * | 1958-04-14 | 1962-04-24 | Kaiser Aluminium Chem Corp | Anodic oxidation of aluminum |
| US2998361A (en) * | 1958-06-11 | 1961-08-29 | Toyo Kohan Co Ltd | Electrochemical treatment of metal surfaces and the products thereof |
| US3227639A (en) * | 1961-10-24 | 1966-01-04 | Aluminum Co Of America | Method of anodizing aluminum with electrolyte containing sulfophthalic acid |
| US3143485A (en) * | 1961-11-28 | 1964-08-04 | Aluminum Co Of America | Aluminum anodizing |
| US3280013A (en) * | 1964-06-02 | 1966-10-18 | Aluminum Co Of America | Anodizing electrolyte and process |
| US3486991A (en) * | 1965-12-27 | 1969-12-30 | Sumitomo Chemical Co | Method of producing a colored anodic oxide film on aluminum |
| US3658665A (en) * | 1966-07-13 | 1972-04-25 | Pechiney Prod Chimiques Sa | Electrolytic method for producing a colored anodized layer on aluminum and alloys of aluminum |
Also Published As
| Publication number | Publication date |
|---|---|
| FR814798A (fr) | 1937-06-29 |
| NL48557C (en(2012)) | |
| ES152467A1 (es) | 1943-03-01 |
| CH206445A (de) | 1939-08-15 |
| GB474323A (en) | 1937-10-29 |
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