MXPA97010210A - Composition and process for treating metal surface aluminife - Google Patents

Abstract

A surface coating highly resistant to corrosion and adherent to paint on aluminum metals can be provided very quickly, if desired in less than one second, by contacting the surface with an aqueous acidic liquid treatment composition containing as proportions solutes. specified for phosphate ions, materials containing titanium, fluoride and an accelerator, the accelerator preferably at least one nitrous acid, nitric acid, tungstic acid, molybdic acid, permanganic acid, water soluble salts of all these acids, and the soluble organoperoxides in ag

Description

"COMPOSITION AND PROCESS TO TREAT THE SURFACE OF ALUMINUM METALS" DESCRIPTION TECHNICAL FIELD This invention relates to a novel liquid surface treatment composition and the process for application to aluminiferous metals, which provide the surface of aluminum metals, ie, aluminum and aluminum alloys containing at least 65 percent by weight. Aluminum weight, with excellent corrosion resistance and paint adhesion. The present invention is applied with a particularly good effect to the surface treatment of aluminum alloys in roll and sheet form.

ANTECEDENTS OF THE TECHNIQUE Liquid compositions, which are often referred to below as "baths" for reasons of abbreviation, even when used by some other method than immersion, which are in general use to treat the surface of aluminum metals, can be broadly classified in types of chromate and types of non-chromate. Chromic acid chromate conversion baths and phosphoric acid chromate conversion baths are typical embodiments of chromate type treatment baths. Chromic acid chromate conversion baths were put into practical use around the year 1950 and are still widely used even today for components of the fin material of the heat exchanger and aviation vehicle. Chromic acid chromate conversion baths contain chromic acid and fluoride as their main components, with the fluoride functioning as a reaction accelerator. These baths coat metal surfaces with conversion coatings containing a certain amount of hexavalent chromium. Phosphoric acid chromate conversion baths originated with the invention disclosed in U.S. Patent No. 2,438,877. These conversion baths containing chromic acid, phosphoric acid and hydrofluoric acid as their main components, coat the metal surface with conversion coatings whose main component is chromium hydrate phosphate. Because these conversion coatings do not contain hexavalent chromium, they are also in widespread use today for applications such as coatings under the paint for a step material and can body for beverages. However, since these chromate-type surface treatment baths themselves contain toxic hexavalent chromium even when the coatings produced by them do not, hexavalent chromium-free treatment baths are desired in view of the environmental problems for the waste. of the baths, rinse waters and similar. Typical of the inventions in the field of chrome-free non-chromate type surface treatment baths is the process disclosed in Japanese Patent Application [Ko ai or Not Examined] Number Sho 52-131937 [131,937 / 1977] . The treatment bath in that reference consists of an aqueous acidic coating solution (pH of about 1.5 to 4.0) containing phosphate, fluoride and zirconium or titanium or both. The treatment of the metal surface with this surface treatment bath forms on it a protective coating whose main component is zirconium oxide or titanium oxide. (This type of coating is often called a "conversion" coating, because it is believed that it also contains substrate cations in the form of oxides and / or phosphates). One window of the non-chromate surface treatment baths is that they are free of hexavalent chromium, and this advantage has resulted in their extensive use at present to treat the surface of drawn and drawn aluminum cans ("DI") and similar. However, non-chromate baths require longer treatment times to coat the formation of chromate surface treatment baths. Shortening the surface treatment time has become an important issue in the last few years due to the increasingly high line speeds that are used to boost productivity. further, the non-chromate baths yield coatings with a lower corrosion resistance and paint adhesion than those of the chromate coatings. The treatment process disclosed in Japanese Patent Application [Kokai or Non-Examined] Number Hei 1-246370 [246,370 / 1989] is an invention whose object is to shorten the aforementioned surface treatment times. In this process, the surface of the aluminiferous metal is first cleaned with an alkaline degreaser and the clean surface is then treated with an aqueous acidic solution (pH 1.5 to 4.0) containing 0.01 to 0.5 gram per liter of zirconium ions, from 0.01 to 0.5 gram per liter of phosphate ions, from 0.001 to 0.05 gram per liter, which is measured as its stoichiometric equivalent as fluorine atoms of the "free" fluoride ions and optionally from 0.01 to 1 gram per liter of ions of vanadium. However, when this process is applied to DI aluminum cans, the resulting film does not always have satisfactory resistance to blackening. Another non-chromate treatment process is disclosed in Japanese Patent Publication Number Sho 57-39314 [39.314 / 1982]. A treatment process is disclosed in which the surface of the aluminum metal is treated with an acidic solution containing hydrogen peroxide, one or more selections of zirconium and titanium salts, and one or more phosphoric acid selections. and condensed phosphoric acids. However, this treatment bath is unstable and, in addition, is also inadequately rapid in terms of surface coating formation. In addition, this document does not provide a specific description or an exposure of the treatment time, treatment temperature or treatment process. It is due to these reasons that surface treatment baths of the currently non-chromate type are almost never used in surface treatment lines for roll or aluminiferous metal sheet, where short treatment times are critical.

In summary, then a composition or process for treating the surface of aluminum metals that can provide short treatment times and which is capable of forming a coating highly resistant to corrosion and intensely adherent to the paint still has to be established in the art, but that is free of hexavalent chromium.

EXHIBITION OF THE INVENTION PROBLEM (S) TO BE RESOLVED THROUGH THE INVENTION The present invention is directed to solving the problems described above for the prior art. In specific terms, the present invention provides a composition and a process for treating the surface of aluminum metals that are capable of rapidly forming a coating highly resistant to corrosion and highly adherent to paint on the surface of aluminum metals.

COMPENDIUM OF THE INVENTION It has been found that a surface treatment composition containing dissolved phosphate ions, a substance (s) containing dissolved titatium and dissolved fluoride, in particular relative amounts and in particular a relative amount of an accelerator which is selected from the specific group of chemical substances, can quickly form a coating very resistant to corrosion and highly adherent to the paint on the surface of aluminum metals. The present invention was achieved based on this discovery. A concentrate or working composition in accordance with the present invention for treating the surface of aluminum metals typically comprises, preferably consists essentially of or more preferably consists of water and the following materials in the relative proportions stated as follows: 0.010 to 5 parts by weight of phosphate ions; 0.010 to 2.0 parts by weight calculated as its stoichiometric equivalent as titanium atoms, of a substance (s) containing dissolved titanium, from 0.010 to 12 parts by weight which is calculated as its stoichiometric equivalent as fluorine atoms, of molecules and / or dissolved anions containing fluorine; and from 0.010 to 2.0 parts by weight of a dissolved accelerator. The bases for the specification of these specific weight ratios for each component will be explained in sequence in the discussion of the composition of the preferred surface treatment baths, vide infra. Counterions for the necessary constituents explicitly mentioned above are also necessary and needed for electrical neutrality. The accelerator increases the rate of coating formation and is selected from the group consisting of oxyacids, such as tungstic acid (i.e., H2WO4), molydic acid (i.e., HM0O3), permanganic acid (i.e. HMn?), Acid nitric acid (i.e., HNO3), nitrous acid (i.e., HNO2), hypochlorous acid (i.e., HC10), chlorous acid (i.e., HCIO2), doric acid (i.e., HCIO3), bromic acid (i.e. HBr? 3), iodic acid (ie, HIO3), perchloric acid (ie, HCIO4), perbromic acid (ie, HBr?), Periodic acid (ie, HIO4), orthoperiodic acid (ie, H5IO6) and salts of oxyacids; peroxoacids, such as peroxomonosulfuric acid (i.e., H2S05), peroxodisulfuric acid (i.e., H2S208), peroxomonophosphoric acid (i.e., H3PO5), peroxodiphosphonic acid (i.e., H4P208), peroxomonocarbonic acid (i.e., H2C04), acid peroxydocarbon (ie, H2C2O5) and any of the peroxoboric acids (ie, HB03-1 / 2H20, HB? * H2 ?, or HB? 5 * H2?) and the peroxo acid salts; superior metal metal cations with at least two stable cationic balance states in cations that do not include oxygen, in aqueous solution such as tetravalent cerium (i.e., Ce + 4), trivalent iron (i.e., Fe + 3) and tetravalent tin (Sn ^ +); hydrogen peroxide (H2O2); and water soluble organoperoxides. the use of a Accelerator selected from this group in a treatment composition in accordance with the present invention yields a considerable improvement in the rate of formation of a coating thick enough to have protective qualities and in corrosion resistance and adhesion to the coating of the coating formed of this way. The four necessary active ingredients in a composition according to the invention as described above do not necessarily have to be all provided by separate chemical substances. For example, fluotitanic acid is well suited to be a source or individual source of both titanium and fluoride. A process according to the present invention for treating the surface of aluminum metals typically comprises the formation thereon of a coating by placing the surface of the aluminum metal in contact, at a temperature from normal room temperature (i.e., at least 10). And more frequently at least 20 ° C) up to 80 ° C, with a surface treatment work composition and then subjecting the surface of the aluminiferous metal carrying the surface treatment bath, to a rinsing with water and usually dried frequently with the use of heat.

DETAILED DESCRIPTION OF THE INVENTION, INCLUDING PREFERRED MODALITIES The source or source of the phosphate ions for a concentrate or work composition in accordance with the present invention may be one or more selections of the orthophosphoric acid (ie, H3PO4) and the neutral and acid salts thereof and concentrated phosphoric acids. such as pyrophosphoric acid (ie, H P2O7) and tripolyphosphoric acid (ie, H5P3O10) and neutral and acid salts of any of these. The source or provenance of selected specific phosphate ions is not critical and the stoichiometric equivalent as phosphate ions of any of these sources or provenances is considered as being the phosphate ions to determine whether a composition is in accordance with the invention and if it is So, what is their degree of preference, regardless of the actual degree of ionization and condensation to form chemical species with POP bonds that may exist in the solution. The content of phosphate ions in a work bath according to the present invention is preferably 0.010 to 5 grams per liter, more preferably 0.050 to 5.0 grams per liter and even more preferably 0.30 to 2.0 grams per liter. liter. Although a coating can be formed at a phosphate ion concentration of less than 0.010 gram per liter, these coatings do not have excellent corrosion resistance or paint adhesion. The use of large concentrations - in excess of 5.0 grams per liter - is not economical: while good quality coatings are formed at these levels, no additional benefits are obtained from the use of these large quantities, so that the cost of bathing of treatment rises without any compensating benefit. The source or source of the titanium-containing substance (s) in a working or concentrated composition according to the present invention is preferably either a salt containing titanium and / or titanyl cations, the anions of which salt may be sulfate, fluoride or the like, or the fluotitanic acid of at least one of its salts, but the selection of the substance (s) containing titanium is not critical. The concentration of the titanium-containing substance (s) in a surface treatment bath according to the invention should be 0.010 to 2.0 grams per liter and preferably 0.10 to 2.0 grams per liter, or more preferably 0.10. at 1.0 gram per liter, which is calculated in each case as titanium. The rapid formation of a satisfactory coating becomes quite problematic with a titanium content of less than 0.010 gram per liter. The use of large quantities - in excess of 2.0 grams per liter - is not economical: even when good quality coatings are formed at these levels, no additional benefits are obtained from the use of these large quantities and the cost of the treatment bath rises . The source or source of fluoride in the composition and surface treatment bath according to the present invention can be such fluorine-containing acids as hydrofluoric acid (ie, HF), fluotitanic acid (i.e., TiFg), fluorosilicic acid (ie, ^ SiFg), fluosilicic acid (ie, H2SiFg), and fluozirconic acid (ie, ^ ZrFg), as well as any of its neutral and acid salts but again the selection of fluoride is not critical. The fluoride content in the surface treatment bath should be within the range of 0.010 to 12 grams per liter, preferably 0.50 to 5.0 grams per liter and more preferably 0.10 to 3.0 grams per liter, in each case calculated as fluorine. Aluminum ions eluting from the substrate are stabilized in the bath as aluminum fluoride by fluoride, and the content levels given above include the amount of fluoride needed to do this. Aluminum fluoride has little effect on the coating forming reactions. For example, a fluorine concentration of approximately 0.2 gram per liter is required in order to stabilize an aluminum concentration in the surface treatment bath of 0.1 gram per liter. Not counting the amount of fluorine that is required to produce aluminum fluoride, the optimum fluoride content for the formation of the coating is 0.010 to 5.0 grams per liter and preferably 0.10 to 3.0 grams per liter, which is calculated in each case as fluorine. A fluorine content of less than 0.010 gram per liter results in inadequate reactivity, and therefore, inadequate coating formation. On the other hand, levels in excess of 12 grams per liter result in an increased degree of etching or chemical attack that causes undesirable unevenness in appearance and these high levels greatly complicate the treatment of the effluent. The accelerator operates in a surface treatment process according to the present invention to accelerate the rate of formation of the titanium coating on the metal surface and also to induce the formation of a coating highly resistant to corrosion and strongly adherent to the painting. The concentration of the accelerator in the surface treatment bath should be within the range of 0.010 to 2.0 grams per liter and preferably falls within the range of 0.10 to 1.1 grams per liter. No acceleration of the film-forming reaction is usually observed at an accelerator concentration of less than 0.010 gram per liter. Accelerator benefits do not additionally add to accelerator levels in excess of 2.0 grams per liter so that additions in excess of this level simply raise costs and are therefore non-economic. An especially preferred accelerator includes at least one selection of the group consisting of nitrous acid, nitric acid, tungstic acid, molydic acid, permanganic acid, all water-soluble salts of all these acids and water-soluble organoperoxides.

The source or source of nitrous acid / nitrite is not critical as long as it is soluble in water; however, the use of the sodium salt (i.e., aN 2) or the potassium salt (i.e., KNO 2) of the nitrous acid is usually preferred due to its relatively low cost. The source or source of nitric acid / nitrate is also not critical, again as long as it is soluble in water; however, the use of the sodium salt (ie, NaN? 3) or the potassium salt (ie, (KNO3) of nitric acid (ie, HNO3) or nitric acid if preferred due to its relatively low cost The source or provenance of tungstic acid / tungstate is not critical as long as it is soluble in water, however again, the use of the sodium salt (ie, Na?) or potassium salt (ie , K2 O4)) of the tungstic acid is preferred due to its relatively low cost. The source or source of molybdic acid / molybdate is not critical as long as it is soluble in water; however, the use of sodium salt (ie, Na2Mo? 4) or the ammonium salt (ie, (NH4) 6M07O24) of the simple or condensed molydric acid is preferred respectively due to its relatively low cost.

The selection of permanganic acid / permanganate is not critical as long as it is soluble in water; however, the use of the sodium salt (i.e., NaMn? 4> or potassium salt (ie, KMn? 4) of the permanganic acid is preferred due to its relatively low cost .The preferred examples of the soluble organoperoxide in water are tertiary butyl hydroperoxide (ie, (CH3) 3-CO-OH), tertiary hexyl hydroperoxide (i.e., CH3CH2 (CH3) 2C-O-OH) and tertiary di-butyl peroxide (i.e., (CH) 3C-O-O-C (CH3) 3). A work surface treatment bath in accordance with the present invention is more conveniently prepared from a concentrated composition in accordance with the present invention, and the pH of the work bath should be within the range of 1.0 to 4.5. A pH of less than 1.0 causes excessive etching of the metal surface by the treatment bath and in this way strongly deteriorates the formation of the film. It becomes very problematic to obtain a coating highly resistant to corrosion and intensely adherent to the paint at a pH in excess of 4.5. The especially preferred pH scale is from 1.3 to 3.0. The pH of the surface treatment bath according to the present invention can be adjusted by adding an acid, e.g., nitric acid, sulfuric acid, hydrofluoric acid or the like to lower the pH or by adding an alkali, e.g., hydroxide of sodium, sodium carbonate, ammonium hydroxide or the like to raise the pH. When in the practice of the present invention the metal substrate is composed of an aluminum alloy with copper or manganese, the stability of the treatment bath can be considerably deteriorated by dissolving into the surface treatment bath of the metal ions derived from the component of copper and manganese alloy. In this case, a difunctional organic acid or its alkali metal salt can be added as a metal sequestering agent in order to chelate the aforementioned alloy metal ions. Examples of suitable organic acids are gluconic acid, heptogluconic acid, oxalic acid, tartaric acid and ethylenediaminetetraacetic acid. A work surface treatment bath in accordance with the present invention can be contacted with the substrate to be treated by any convenient method and is normally used as part of a process sequence including other steps. A preferred generalized process sequence, for example, is as follows: 1. Clean the surface: degrease with a system based on an alkaline acidic material or solvent. 2. Rinse with water. 3. Surface treatment with the treatment bath according to the temperature of treatment of the present invention: room temperature up to 80 ° C. Treatment time: from 0.5 to 60 seconds treatment technique: spraying or immersion 4. Rinse with water. 5. Rinse with deionized water. 6. Drying. A treatment process according to the present invention is carried out by placing a work surface treatment bath as described above in contact with a surface of the aluminiferous metal at room temperature up to 80 ° C., and preferably from 35 ° C to 70 ° C during a contact time period which is at least, preferably increased in the determined order of 0.50, 1.0 or 2.0 seconds, and preferably independently is not greater than, with increased preference in the proportioned order of 120, 90, 60, 50, 40, 30, 20, 10, 8.0, 5.0, 3.0 or 2.5 seconds. Treatment times of less than 0.5 second are associated with insufficient reaction and at least may not yield the formation of a coating with good resistance to corrosion and adhesion to the paint. The coating properties usually do not further improve to treatment time periods greater than 120 seconds and in some cases do not further improve even after treatment times of a few seconds, while any prolonged treatment time increases the cost of the process. The coating formed in a process according to the invention preferably contains a mass per unit area of 3 to 50, or more preferably 5 to 30 milligrams per square meter (usually abbreviated below as "mg / m ^") of Titanium atoms are measured as such by a certain method, such as X-ray fluorescence, which is independent of the chemical nature of the titanium atoms. When the surface coating mass is less than 3 milligrams per square meter as titanium, there is usually inadequate corrosion resistance through the resulting coating. At the other end of the scale, there is usually an unsatisfactory adhesion to the paint by coating when the coating weight exceeds 50 milligrams per square meter. Aluminum metals that can be subjected to surface treatment by a process in accordance with the present invention encompass both pure aluminum and aluminum alloys, for example, alloys of Al-Cu, Al-Mn, Al-Mg, Al-Si and Al -Zn. The shape and dimensions of the aluminum metal used in the process of the invention are not critical and for example, the sheet and the various molding configurations are within the scope of the process. The surface treatment baths and the process according to the present invention will be illustrated in greater detail below through both the working and comparison examples.

EXAMPLES The sequence of the treatment process and the other conditions indicated immediately below apply to each of Examples 1 to 9 and Comparison Examples 1 to 7.

Sample Material A sheet of aluminum-agnesium alloy according to the Japanese Industrial Standard (abbreviated below usually as "JIS") 5182 was used. Dimensions: 300 millimeters (which is usually abbreviated below as "mm") x 200 mm. Thickness of the blade: 0.25 mm.

Treatment Conditions A treated sheet was prepared by conversion by the sequencing of the following processes in sequence l? 2 - »3 - > Four. Five ? 6. 1. Degreasing (60 ° C, 10 seconds, spraying) A 2 percent aqueous solution of a commercially available alkaline degreaser, FINECLEANER® 4377K from Nihon Parkerizing Company, Limited, was used. 2. Rinse with water (room temperature, 10 seconds, spraying). 3. Treatment of metal according to the invention, a comparison thereto (spraying). The components used in the surface treatment baths, their concentrations in these baths and the conditions for the processes according to the invention in Examples 1 to 9 and for Comparison Examples 1 to 5 are shown in the Tables presented then. The surface treatment conditions for Comparison Examples 6 and 7 are mentioned separately. An aqueous solution of 40 percent fluotitanic acid - a compound that is both a substance (s) containing titanium and a fluoride - was used in Examples 1, 4, 7 and 9, and in Comparative Example 2 as the source or provenance of both of these necessary components of a bath in accordance with the invention. All the amount of the fluotitanic acid used is shown in the Tables that will be given below under a column heading as the source or source of titanium and under another heading as the source or source of fluoride, but the amount in fact did not double in the work bathroom An aqueous solution of 67.5 percent nitric acid was used both as an accelerator and for pH adjustment in Examples 1 and 5. 4. Rinse with water (room temperature, 10 seconds, spray) 5. Rinse with deionized water (temperature environment, 5 seconds, spraying) 6. Heating and drying (80 ° C, 3 minutes, hot air oven) A small spraying apparatus was used for defatting, rinsing with water and rinsing with deionized water and treatment according to the invention or a comparison thereof. The specific small spraying apparatus used was designed to reproduce the same spray conditions as in a continuous surface treatment line for the actual treatment of the aluminum alloy roll. The following methods were used to test the weight of the coating, the corrosion resistance and adhesion to the paint of the treated specimens. (1) Coating Weight The added Ti or Zr, in milligrams per square meter in the treated sheet, was measured using a fluorescent X-ray analyzer (R1X1000 from Rigaku Denki Kogyo Kabushiki Kaisha). (2) Corrosion Resistance The salt spray test in accordance with JIS Z 2371 was used to evaluate the corrosion resistance. The development of corrosion in the treated sheet was visually evaluated after 150 hours of salt spray test, and the results were classified according to the following scale: +++: corroded area that was less than 10 percent; ++: corroded area that was greater than or equal to 10 percent, but less than 50 percent; +: corroded area that was greater than or equal to 50 percent, but less than 90 percent; x: corroded area that was greater than or equal to 90 percent. (3) Adhesion to the Paint The surface of the aluminum-magnesium alloy sheet treated by conversion was painted with an epoxy-phenol paint for can lids to provide an 8-micron paint film thickness followed by baking for 3 months. minutes at 220 ° C. The polyamide film was then inserted between two of these painted surfaces with hot press bonding at 200 ° C for 2 minutes. The compound bound with hot press was cut into strips 10 millimeters wide x 120 millimeters long, which were the test specimens. A test specimen was peeled off from the polyamide film using a T-peel test procedure and the peel strength at this point is designated as the primary adhesion. In order to evaluate the durability of adhesion to water, a test specimen prepared as described above was immersed in boiling deionized water for 60 minutes and then subjected to the measurement of the peel strength in the same procedure of detachment test T. The result in this case is designated as the secondary adhesion. The larger values for peel strength are indicative of better adhesion to the paint. Sufficient operation for practical applications was a resistance to loosening of at least a force of 7.0 kilograms (hereinafter abbreviated usually as "kgf") / 10 millimeters in width in the case of primary adhesion and a resistance to loosening at less 5.0 kgf / 10 mm wide in the case of secondary adhesion.

Comparison Example 6 The same treatment process was carried out as in Example 1, with the exception that a 2 percent aqueous solution of the commercially available zirconium-based treatment agent, ALODINE ™ 4040 from Nihon Parkerizing, was used. Company, Limited, as the surface treatment bath in step 3 of the process. This treatment bath was sprayed onto the aluminum-magnesium alloy sheet as described above for 30 seconds at 40 ° C. The test results are disclosed in the tables presented below.

Comparison Example 7 The same treatment as in Example 1 was carried out, with the exception that a 2 percent aqueous solution of a commercially available zirconium-based treatment agent ALODINE ™ 4040, from Nihon Parkerizing Company, was used. , Limited, as the treatment bath. The bath was sprayed onto the same aluminum-magnesium alloy sheet as described above for 5 seconds at 40 ° C. The test results are disclosed in the tables presented below.

Benefits of the Invention As the foregoing description has elucidated, the application of a working treatment composition in a surface treatment process in accordance with the present invention to aluminum metals rapidly forms a corrosion resistant and strongly adherent coating to paint on the metal surface before painting or forming it. In addition, when the aluminiferous metal of the substrate is in the form of a continuous roll or sheet, the rapidity of the treatment supports the higher speeds in the production line and allows consolidation (saving space) of the treatment facilities. As a consequence of these effects, the surface treatment concentrates, the work baths and the processes in accordance with the present invention for application to aluminum metals have a very high degree of practical utility.

Table 1 COMPONENTS USED IN THE TREATMENTS OF EXAMPLES 1 A 9 AND EXAMPLES 1 TO 5 OF COMPARISON AND IDENTIFICATION SYMBOLS FOR THEMSELVES Material Component (s) of Source or Provenance Compound Formula Chemical Symbol Ions of 85% orthophosphoric acid Phosphate in water H3PO4 Substance (s) 40% fluotitanic acid containing in water r ^ TiFg titanium 24% titanic sulfate in water Ti (S04) 2 titanyl sulfate in water, 10% Ti TIOSO4 40% fluotitanic acid in water H2TiFg % hydrofluoric acid Fluoride in water HF 40% fluosilic acid in H2SiFg water 96% of ammonium acid fluoride in water NH HF2 67. 5% nitric acid in water HNO3 potassium permanganate KMnO 97% pure sodium nitrite NaN02 V Accelerator sodium tungstate dihydrate Na2W0 -2H OW heptamolybdate ammonium tetrahydrate (NH4) M? 7? 24 • 4H20 X 69% tertiary butyl hydroperoxide in water (Cr ^^ C-O-OH Y % stannic chloride in water SnCl Z 67. 5% nitric acid in water HN03 T Regulator of 97% sulfuric acid pH in water H2SO4 % ammonia in water NH4OH Table 2 COMPOSITIONS OF SURFACE TREATMENT BATHS IN COMPLIANCE WITH THE INVENTION No. Grams per Liter in Bath: pH of the type of pH Ex. Compound Fountain or Source or Source or Bath of Ti / (Ti) Origin Provenance Proven Phosphate / Fluoride / Accelerator (P0 ~ 3) (F) dor / (Active Accelerator) 1 5.0 of A 1.0 of a / 5.0 of A / 1.00 of T / T 1.3 /(0.58) (0.82) (1.39) (0.68) 2 2.0 of C / 0.2 of a / 0.5 of a / 0.10 of / a 1.8 (0.20) (0.16) (0.10) (0.09) 3 30.0 from B 4.0 from a / 15.0 from a / 0.50 from V / a 1.0 /(.44) (3.30) (2.85) (0.49) 4 10.0 from A 1.0 from a / 10.0 of A. { 1.00 from V / b 1.5 /(l.7) (0.82) /(2.78) (0.97)} +. { 0.10 of U / (0.10)) 20.0 of B 1.5 of a /. { 0.5 of a /. { 0.30 of T / T 1.3 /(O.96) 1.24 (0.10)} + (0.20)) +. { 0.05. { 0.5 of b / of X /(0.05)} (0.16) . 0 of C / 1.0 of a / 2.0 of c /. { 0.30 of Y / b 4.2 (0.48) (0.82) (1.28) (O .21)} +. { 0.10 of W / (0.10)} . { 0.30 of 2.5 of a /. { 3. Or of A 1.0 of Y / 2.5 A / (2.06) /(0.83)} + (0.69) (0.35)} + (2.0 of c / { 5.0 of C (1.28)) / (0.50)} 1. 0 of B / 0.04 of a / 0.2 of b / 0.03 of U / 4.0 [0.05) (0.03) (0.06) (0.03) 2. 0 from A / 0.5 from a / 2.0 from A / 3.00 from Z / a 1.6 (0.23) (0.41) (0.56) (0.15) Table 3 COMPOSITIONS OF SURFACE TREATMENT BATHROOMS FOR THE COMPARISON EXAMPLES 1 TO 5 No. G Grraammoc? Ss ppoorr LLiittrroo ddleelí BBaaññoo ddee :: pH of the type of pH Ex. Compound Source or Source 0 Source 0 of the Bath of Ti / (Ti) Origin Provenance Origin Regu¬ Phosphate Component / Fluoride / Accelerator for (P04 ~ 3) (F) dor / (Active Acceleration dor) 1 none 1.0 of a / 0.5 of b / 1.00 of V / a 1.3 (0.82) (0.16) (0.97) . 0 from A / none 5.0 from A / 0.30 from W / 1.6 (0.58) (1.39) (0.27) . 0 from C / 1.5 from a / none 1.0 from Y / 1.2 (1.00) (1.24) (0.69) 4 30.0 of B / 4.0 from a / 5.0 of a /. { 0.5 of V / b 5.0 (1.44) (3.30) (0.95) (0.49) 10.0 of B / 1.0 of a / 5.0 of a / none b 1.5 (0.48) (0.82) (0.95) Table 4 RESULTS OF PROOF OF CONDITIONS OF THE PROCESS AND EVALUATION Example No. Conditions During Classification Mass - Adhesion to ("Ex") or Addition Treatment paint the Example Example according to the Invention of Ti, then kgf / 10 mm Comparison or Comparison mg / m2 of 150 Width ("CE") hours of Tempera- Time of the Pri- Setura test, ° C Contact, of sprinkler- Seconds Hard of river Sal Example 1 40 15 +++ 10.8 8.3 Example 2 45 40 20 +++ 9.4 6.7 Example 3 40 12 +++ 9.0 6.7 Example 4 65 15 +++ 11.4 9.2 Example 5 35 4.5 +++ 10.5 9.0 Example 6 45 43 +++ 9.3 6.8 Example 7 60 25 +++ 1.9 7.

Example 8 35 50 9.0 +++ 7.5 5.3 Example 9 50 12 20 +++ 7.2 5.5 CE 1 50 10 0 x 3.8 1.0 CE 2 55 5 20 + 6.0 2.9 CE 3 35 40 1.0 x 4.0 1.3 EC 4 45 8 17 ++ 5.2 3.4 CE 5 60 30 2.0 x 5.0 1.3 CE 6 40 30 * 18 of Zr ++ 7.2 5.0 CE 7 40 5 * 5 of Zr + 4.6 2.7 Fitting Notes for Table 4 * Titanium is not added in these comparison examples, which were used as the treatment composition that does not contain titanium

Claims (10)

R E I V I N D I C A C I O N S

1. An aqueous liquid composition which is suitable as such, and therefore is a working composition, or after dilution with additional water, and is therefore a concentrated composition, for treating the surface of aluminum metals to form a protective coating to the corrosion and adhesion to the paint therein, the composition comprising the following components in relative amounts as mentioned below: (A) from 0.01 to 5 parts by weight of dissolved phosphate ions; (B) from 0.01 to 2 parts by weight, calculated as its stoichiometric equivalent as titanium atoms, from dissolved molecules, ions, or both containing titanium atoms; (C) from 0.01 to 12 parts by weight, calculated as their stoichiometric equivalent as fl ions, dissolved molecules, anions, or both containing fluorine atoms; and (D) from 0.01 to 2 parts by weight of the accelerator.

2. A composition according to claim 1, wherein the accelerator comprises at least one material that is selected from the group consisting of nitrous acid, tungstic acid, molybdic acid, permanganic acid, water soluble salts of all the above acids , and water soluble organoperoxides, and optionally also contain nitrate ions.

3. A working composition according to claim 2, wherein the composition has a pH of 1.0 to 4.5 and contains 0.01 to 5 grams per liter of dissolved phosphate ions, from 0.01 to 2 grams per liter, calculated as atoms titanium, dissolved molecules, ions or both that contain titanium atoms; from 0.01 to 12 grams per liter, calculated as fluorine atoms, dissolved molecules, anions or both that contain fluorine atoms; and from 0.01 to 2 grams per liter of the accelerator.

4. A working composition according to claim 3, wherein the composition contains from 0.05 to 5 grams per liter of dissolved phosphate ions, from 0.10 to 2 grams per liter, calculated as titanium atoms, from dissolved molecules, ions or both that contain titanium atoms; and from 0.05 to 5.0 grams per liter, calculated as fluorine atoms, dissolved molecules, anions or both that contain fluorine atoms; and the accelerator is selected from the group consisting of nitrous acid, nitric acid, tungstic acid, molybdic acid and permanganic acid, water soluble salts of all the above acids and water soluble organoperoxides.

5. A working composition according to claim 4, wherein the composition has a pH of 1.3 to 3.0 and contains 0.30 to 2.0 grams per liter of dissolved phosphate ions, from 0.10 to 1.0 gram per liter, calculated as atoms titanium, dissolved molecules, ions or both that contain titanium atoms; from 0.10 to 2.0 grams per liter, calculated as fluorine atoms, dissolved molecules, anions or both that contain fluorine atoms; and from 0.10 to 1.1 grams per liter of the accelerator.

6. A working composition according to claim 1, wherein the composition has a pH of 1.0 to 4.5 and contains 0.01 to 5 grams per liter of dissolved phosphate ions, from 0.01 to 2 grams per liter, calculated as atoms titanium, dissolved molecules, ions or both that contain titanium atoms; from 0.01 to 12 grams per liter, calculated as fluorine atoms, dissolved molecules, anions or both that contain fluorine atoms; and from 0.01 to 2 grams per liter of the accelerator.

7. A working composition according to claim 6, wherein the composition contains from 0.05 to 5 grams per liter of dissolved phosphate ions; from 0.10 to 2 grams per liter, calculated as titanium atoms, dissolved molecules, ions or both that contain titanium atoms; and from 0.05 to 5.0 grams per liter, calculated as fluorine atoms, dissolved molecules, anions or both that contain fluorine atoms; and the accelerator is selected from the group consisting of nitrous acid, nitric acid, tungstic acid, molybdic acid, permanganic acid, water soluble salts of all the above acids and water soluble organoperoxides. A working composition according to claim 7, wherein the composition has a pH of 1.3 to 3.0 and contains 0.30 to 2.0 grams per liter of dissolved phosphate ions, from 0.10 to 1.2 grams per liter, calculated as atoms of titanium, of dissolved molecules, ions or both that contain quantities of titanium; from 0.10 to 2.8 grams per liter, calculated as fluorine atoms, dissolved molecules, anions or both that contain fluorine atoms; and from 0.10 to 1.1 grams per liter of the accelerator. 9. A process for treating an aluminiferous metal surface as the process comprises the steps of: (I) putting the aluminum metal surface in contact, at a temperature from the normal ambient temperature to 80 ° C, with a working composition of according to any of claims 3 to 8 for a period of time of at least 0.5 second; and (II) discontinuing the contact established in step (I) and then subjecting the surface of the aluminiferous metal carrying the residue of the surface treatment bath with a rinse with water and optionally; (III) drying the rinsed surface from the end of step (II). A process according to claim 9, wherein the weight of the coating is from 3 to 50 milligrams per square meter calculated as titanium that is produced on the surface of the aluminiferous metal during the process.