US3672821A - Inhibitor for aluminum in alkaline solutions - Google Patents
Inhibitor for aluminum in alkaline solutions Download PDFInfo
- Publication number
- US3672821A US3672821A US115756A US3672821DA US3672821A US 3672821 A US3672821 A US 3672821A US 115756 A US115756 A US 115756A US 3672821D A US3672821D A US 3672821DA US 3672821 A US3672821 A US 3672821A
- Authority
- US
- United States
- Prior art keywords
- aluminum
- weight
- solutions
- solution
- inhibitor
- 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
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- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 title abstract description 28
- 229910052782 aluminium Inorganic materials 0.000 title abstract description 22
- 239000012670 alkaline solution Substances 0.000 title abstract description 19
- 239000003112 inhibitor Substances 0.000 title abstract description 12
- 229910052910 alkali metal silicate Inorganic materials 0.000 abstract description 5
- 238000005260 corrosion Methods 0.000 abstract description 5
- 230000007797 corrosion Effects 0.000 abstract description 5
- 230000002401 inhibitory effect Effects 0.000 abstract description 5
- 230000000694 effects Effects 0.000 abstract description 4
- 239000002253 acid Substances 0.000 abstract description 3
- 150000001447 alkali salts Chemical class 0.000 abstract description 3
- 238000000034 method Methods 0.000 abstract description 3
- 150000007513 acids Chemical class 0.000 abstract 2
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 45
- 239000000243 solution Substances 0.000 description 24
- 235000010210 aluminium Nutrition 0.000 description 20
- 229920002125 Sokalan® Polymers 0.000 description 17
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 6
- 239000004584 polyacrylic acid Substances 0.000 description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 239000003513 alkali Substances 0.000 description 4
- 239000007864 aqueous solution Substances 0.000 description 4
- 238000007654 immersion Methods 0.000 description 4
- 150000003839 salts Chemical class 0.000 description 4
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 4
- 229910001854 alkali hydroxide Inorganic materials 0.000 description 3
- 150000008044 alkali metal hydroxides Chemical class 0.000 description 3
- 150000001875 compounds Chemical class 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 235000019353 potassium silicate Nutrition 0.000 description 3
- 239000011734 sodium Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 description 2
- 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 2
- 150000003863 ammonium salts Chemical class 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- ZCDOYSPFYFSLEW-UHFFFAOYSA-N chromate(2-) Chemical class [O-][Cr]([O-])(=O)=O ZCDOYSPFYFSLEW-UHFFFAOYSA-N 0.000 description 2
- 230000005764 inhibitory process Effects 0.000 description 2
- 239000007800 oxidant agent Substances 0.000 description 2
- 229910052708 sodium Inorganic materials 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-N 2-Propenoic acid Natural products OC(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- 229910019142 PO4 Inorganic materials 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- 239000004115 Sodium Silicate Substances 0.000 description 1
- 150000004649 carbonic acid derivatives Chemical class 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 235000021317 phosphate Nutrition 0.000 description 1
- 150000003013 phosphoric acid derivatives Chemical class 0.000 description 1
- 238000005554 pickling Methods 0.000 description 1
- 238000006116 polymerization reaction Methods 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- XAEFZNCEHLXOMS-UHFFFAOYSA-M potassium benzoate Chemical compound [K+].[O-]C(=O)C1=CC=CC=C1 XAEFZNCEHLXOMS-UHFFFAOYSA-M 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 159000000000 sodium salts Chemical class 0.000 description 1
- 229910052911 sodium silicate Inorganic materials 0.000 description 1
- 229940032158 sodium silicate Drugs 0.000 description 1
- 235000019794 sodium silicate Nutrition 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
- C23F11/00—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent
- C23F11/06—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in markedly alkaline liquids
Definitions
- alkali silicate inhibitors such as incrustation of the aluminum
- This invention relates to the inhibition of metallic aluminum in alkaline solutions by the action of polyacrylic acids and/or their water-soluble salts.
- the polyacrylic acids are particularly eflicient at relatively low inhibitor concentrations and preferably 0.05 to 0.05% by weight, based on the weight of the alkaline solution. Equal amounts of alkali silicate have no inhibiting eifect and they even intensify the corrosion of metal caused by the alkali and a satisfactory degree of inhibition can be attained in this case by essentially higher alkali silicate concentrations only.
- water-soluble salts thereof can also be used, particularly the sodium, potassium and ammonium salt.
- alkaline solutions used in the treatment of aluminum in carrying out the present invention contain particularly sodium hydroxide or potassium hydroxide.
- other substances of strongly alkaline reaction such as alkali carbonates and alkali phosphates can also be used, either alone or in mixture with alkali hydroxides.
- EXAMPLE 1 Three aqueous solutions were prepared (a) from water and 1% by weight of NaOH;
- Table 1 shows the weight of the alumi num removed in each case from, the test piecesduring immersion under the above described conditions, at different NaOH concentrations.
- polyacrylic acid a water-soluble alkali salt thereof, substantially equal resultsare obtained.
- Table 2 shows theweight of aluminum removed in each case from the test pieces during immer sionunder the above described conditions, in dependence on the specific viscosity of :the 'polyacrylic acids used.
- the term' inhibitor is used herein to denote compounds or compositions having the effect of slowing down corrosion of aluminum in alkaline solution.
- polyacrylic acids isused herein to denote products obtainable by polymerization of acrylic acid weight of K 'PO Such solutions are used for the treat-.
Abstract
A METHOD OF INHIBITING THE CORROSION OF METALLIC ALUMINUM DURING ITS TREATMENT WITH ALKALINE SOLUTIONS. AS THE INHIBITOR IN THE ALKALINE SOLUTION, ACCORDING TO THE INVENTION POLYACRYLIC ACIDS HAVING A SPECIFIC VISCOSITY IN THE RANGE OF 0.07 TO 0.90, PREFERABLY 0.09 TO 0.20, ARE USED IN A PREFERRED AMOUNT OF 0.05 TO 0.5% BY WEIGHT, BASED ON THE WEIGHT OF THE ALKALINE SOLUTION. INSTEAD OF THE POLYACRYLIC ACIDS THEIR WATER-SOLUBLE ALKALI SALTS CAN BE USED. BY THE PRESENT INVENTION THE UNDESIRED SIDE EFFECTS OF ALKALI SILICATE INHIBITORS, SUCH AS INCRUSTATION OF THE ALUMINUM, CAN BE AVOIDED.
Description
United States Patent 3,672,821 INHIBITOR FOR ALUMINUM IN ALKALINE SOLUTIONS Hans-Joachim Schlussler, Dnsseldorf-Holthausen, Germany, assignor to Henkel & Cic GmbH, Dusseldorf, Germany No Drawing. Continuation of abandoned application Ser. No. 768,516, Oct. 17, 1968. This application Feb. 16, 1971, Ser. No. 115,756
Int. Cl. C23f 11/06 US. Cl. 212.7 2 Claims ABSTRACT OF THE DISCLOSURE A method of inhibiting the corrosion of metallic aluminum during its treatment with alkaline solutions. As the inhibitor in the alkaline solution, according to the invention polyacrylic acids having a specific viscosity in the range of 0.07 to 0.90, preferably 0.09 to 0.20, are used in a preferred amount of 0.05 to 0.5% by weight, based on the weight of the alkaline solution. Instead of the polyacrylic acids their water-soluble alkali salts can be used.
By the present invention the undesired side effects of alkali silicate inhibitors, such as incrustation of the aluminum, can be avoided.
This invention relates to the inhibition of metallic aluminum in alkaline solutions by the action of polyacrylic acids and/or their water-soluble salts.
It has been known to inhibit aluminum metal in alkaline solutions by the action of oxidizing agents, e.g. permanganates or chromates, which are active in the alkaline range. However, the efiiciency of these oxidizing agents is limited and relatively high amounts thereof must be used. In view of the physiological labor conditions and reasons connected with waste-water purification, chromates cannot be used in practice at present any more. The use of waterglass as an inhibitor for aluminum has also been known. It yields good results if it is applied in the necessary high proportions.
It has been found that the addition of water glass in the necessary high proportions, to alkaline solutions frequently results in unpleasant side effects, for example in crustformation or incrustation on the parts or objects treated with said solutions, particularly if said parts or objects are after-treated with acid, in order to remove the excess of akali. Such incrustations do not react with solutions conventionally used for their removal. They can be removed with hydrofluoric acid only, the use of which, however, raises physiological problems.
It has now been found that these difficulties can be eliminated if--instead of water-glass-polyacrylic acids having a specific viscosity of 0.07 to 0.90 are added to the alkaline solutions as inhibitors for aluminum. It has been found preferable to use polyacrylic acids having a specific viscosity in the range of 0.90 to 0.20. The inhibiting effect decreases in general if the specific viscosity is higher than 0.2. In some cases, for example in pickling aluminum, a not too strong reduction of the attack on aluminum is desirable. The specific viscosity 1; of a substance is calculated from the viscosity of the solution according to the following formula:
viseosity of the solution viscosity of the solvent It has been found that the polyacrylic acids are particularly eflicient at relatively low inhibitor concentrations and preferably 0.05 to 0.05% by weight, based on the weight of the alkaline solution. Equal amounts of alkali silicate have no inhibiting eifect and they even intensify the corrosion of metal caused by the alkali and a satisfactory degree of inhibition can be attained in this case by essentially higher alkali silicate concentrations only.
Instead of the free polyacrylic acids, water-soluble salts thereof can also be used, particularly the sodium, potassium and ammonium salt.
The alkaline solutions used in the treatment of aluminum in carrying out the present invention, contain particularly sodium hydroxide or potassium hydroxide. However, other substances of strongly alkaline reaction, such as alkali carbonates and alkali phosphates can also be used, either alone or in mixture with alkali hydroxides.
It has been found that by using the above described polyacrylic acids and/or their water-soluble salts, a retardation of the attack by the alkaline solution on the aluminum metal takes place, which is particularly suitable for commercial practice. At the same time, crust formation or the formation of coatings, which cause difiiculties in the application of the hitherto used alkali silicate inhibitors, is avoided.
The following examples describe some embodiments of the invention, to which the invention is not limited.
EXAMPLE 1 Three aqueous solutions were prepared (a) from water and 1% by weight of NaOH;
(b) from water, 1% by weight of NaOH and 0.2% by weight of polyacrylic acid having a specific viscosity of 0.15;
(c) from water and 1% by weight of NaOH and 0.2% by weight of sodium-silicate, in which the mol-ratio SiO :Na O was 3.3:1.
In each said solutions (a), (b) and (c) a weighed 99.5% sheet aluminum of 1 mm. thickness was immersed and leftimmersed for 60 minutes. The test pieces were then removed from the solution, rinsed with water and weighed in order to determine the weight of aluminum removed from the test piece during said 60 minutes. The weight of aluminum removed during immersion from the test pieces amounted in grams, per square meter, and per minute in test (a), i.e. treatment with NaOH only, to 0.17 grain" in test (c), i.e. treatment with solution (c), to 0.26 gram in test (b), i.e. according to the invention, to 0.024
gram
If the treatment is carried out in the above described manner, but with solutions (a), (b), and (c), which contain now in each case 3% of NaOH in solution, the weight of aluminum removed during immersion from test pieces amounted in grams per square meter, and per minute In 3 series (a), (b), (c) of tests aluminum sheet pieces of 99.5% by weight of aluminum, having a thickness of 1 mm. and dimensions of 5X 10 cm., were exposed by immersion to the action of aqueous NaOH solutions of different NaOH concentrations at 65 C. for 15 minutes.
In series (a) the NaOH solution contained no inhibitor;
in series (b) the NaOH solution contained 0.2% by 7 weight (based on the weight of the solution) of polyacrylic acid having a specific viscosity of 0.15;'in series the NaOH solution contained 0.2% by weight (based on the weight of the solution) of water-glass of a moi-ratio of SiO =3.3:l. 'Subsequently'the test pieces were re moved from the solutions, rinsed and dried.
The following Table 1 shows the weight of the alumi num removed in each case from, the test piecesduring immersion under the above described conditions, at different NaOH concentrations. In using instead of polyacrylic acid a water-soluble alkali salt thereof, substantially equal resultsare obtained.
TABLE 1 Weight of aluminum removed in grams per square meter and per minute Aluminum sheet pieces of the dimensions 0.1x5x l0 7 cm. were exposed to the actionof aqueous solutions containing 1% by weight of NaOH and 0.1% by Weight of polyacrylic acid of varying specificviscosity- Said test pieces were immersedinsaid solutions of 20 C. for 60 minutes.
The following Table 2 shows theweight of aluminum removed in each case from the test pieces during immer sionunder the above described conditions, in dependence on the specific viscosity of :the 'polyacrylic acids used.
TABLE 2 Weight of aluminum removed in grams per square and per minute Specific viscosityof the polyacrylic acid:
It will be understood from the above that this invention is not limited to the specific details and conditions disclosed above and can be carried out with various modifications. Thus-as already mentioned above-in the alkaline solutions for the treatment of aluminum according to the invention, other substances of strong alkaline reaction may be used, alone or in mixture with alkali hydroxides. As examples of such solutions, the following are mentioned: an aqueous solution containing 0.1 to 10% by weight of Na cO an aqueous solution containmg 1 to 5% by weight of NaOH and 0.05 to 0.5% by Solution 0 i ment of aluminuminamanner substantially analogous to that described abovein the case of solutions, in which the alkali consists of alkali hydroxide. g "'The term' inhibitor is used herein to denote compounds or compositions having the effect of slowing down corrosion of aluminum in alkaline solution. The term polyacrylic acids isused herein to denote products obtainable by polymerization of acrylic acid weight of K 'PO Such solutions are used for the treat-.
(CH CHCOOH). The test described in the above Ex-- ample 'l'was carried out atordinary room temperature of about. 20 C. The percent and parts stated herein are by weight, if not otherwise stated.
- What is claimed is:
1. Aprocess for inhibiting the corrosion of metallic aluminum in the presence of a strong alkalinesolution selected from the group consistingof aqueous sodium sists of the addition of from 0.05 to 0.5% by weight, based'on theweight of said alkaline solution, to said solurange of from 0.09 to 0.90 and selected from the group consisting of: polyacrylicacids and water-soluble salts of said acidsselected from the group consisting of the sodium salt, the potassium salt and the ammonium salt, said i specific'viscosity being determined according to the formula viscosity of the solution if viscosity of the solvent where the viscosity is determined of a 0.7% solution of said polyacrylic acid in a2 N sodium hydroxide solution in water; r r
2. The process of claim 1 wherein said compound has a specific viscosity inthe range of frorn0.09 to 0.20.
References Cited UNITED STATES PATENTS I 7 2,653,860 9/1953 Meyes 25279.5 X 2,671,717 3/1954 Ferguson 252-79.5 X 2,783,200 2/1-957 Crum et a1. 252181 UX 2,829,114 4/1958 Hervert 212.5 X 2,942,955 6/1960 Hannah 25279.5 X 2,975,039 3/19 61 Elliott 25279.5 X 3,080,264 3/1963 Zimmie et al. 134-22 R 3,405,072 10/1968 Kinnavy 252-396 X FOREIGN PATENTS 666,119 7/1963 Canada 134-2 MORRIS O. WOLK, Primary Examiner B. S. RICHMAN, Assistant Examiner U.S. C1. X.R.
=hyd-roxide and. aqueous potassium hydroxide which 'contion of. a compound having a specific viscosity in the
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US11575671A | 1971-02-16 | 1971-02-16 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3672821A true US3672821A (en) | 1972-06-27 |
Family
ID=22363226
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US115756A Expired - Lifetime US3672821A (en) | 1971-02-16 | 1971-02-16 | Inhibitor for aluminum in alkaline solutions |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US3672821A (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4116849A (en) * | 1977-03-14 | 1978-09-26 | The Procter & Gamble Company | Thickened bleach compositions for treating hard-to-remove soils |
| US4392972A (en) * | 1981-12-30 | 1983-07-12 | Union Carbide Corporation | Aluminum-corrosion inhibitive heat transfer fluid |
| US4402847A (en) * | 1982-05-19 | 1983-09-06 | Basf Wyandotte Corporation | High lead solder corrosion inhibitors |
| US4404114A (en) * | 1982-06-17 | 1983-09-13 | Union Carbide Corporation | Acrylate/silicate corrosion inhibitor |
| US4592785A (en) * | 1983-12-15 | 1986-06-03 | General Electric Company | Proteinaceous soil removal process |
| US5607718A (en) * | 1993-03-26 | 1997-03-04 | Kabushiki Kaisha Toshiba | Polishing method and polishing apparatus |
| US8530143B2 (en) | 2010-11-18 | 2013-09-10 | Eastman Kodak Company | Silicate-free developer compositions |
| US8939080B2 (en) | 2010-11-18 | 2015-01-27 | Eastman Kodak Company | Methods of processing using silicate-free developer compositions |
| US8940474B2 (en) | 2010-11-18 | 2015-01-27 | Eastman Kodak Company | Method of providing lithographic printing plates |
-
1971
- 1971-02-16 US US115756A patent/US3672821A/en not_active Expired - Lifetime
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4116849A (en) * | 1977-03-14 | 1978-09-26 | The Procter & Gamble Company | Thickened bleach compositions for treating hard-to-remove soils |
| US4392972A (en) * | 1981-12-30 | 1983-07-12 | Union Carbide Corporation | Aluminum-corrosion inhibitive heat transfer fluid |
| US4402847A (en) * | 1982-05-19 | 1983-09-06 | Basf Wyandotte Corporation | High lead solder corrosion inhibitors |
| US4404114A (en) * | 1982-06-17 | 1983-09-13 | Union Carbide Corporation | Acrylate/silicate corrosion inhibitor |
| US4592785A (en) * | 1983-12-15 | 1986-06-03 | General Electric Company | Proteinaceous soil removal process |
| US5607718A (en) * | 1993-03-26 | 1997-03-04 | Kabushiki Kaisha Toshiba | Polishing method and polishing apparatus |
| US8530143B2 (en) | 2010-11-18 | 2013-09-10 | Eastman Kodak Company | Silicate-free developer compositions |
| US8939080B2 (en) | 2010-11-18 | 2015-01-27 | Eastman Kodak Company | Methods of processing using silicate-free developer compositions |
| US8940474B2 (en) | 2010-11-18 | 2015-01-27 | Eastman Kodak Company | Method of providing lithographic printing plates |
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