JP3784400B1 - Chemical conversion solution for metal and processing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a chemical conversion treatment liquid and a method capable of imparting excellent corrosion resistance and paint adhesion without using hexavalent Cr to a metal material and having high anti-sludge property.
SOLUTION: Water-soluble trivalent Cr compound component (A), water-soluble Ti and / or Zr compound component (B), water-soluble nitric acid compound component (C), water-soluble Al compound component (D) and F compound component ( The aqueous acidic chemical conversion treatment solution containing E) and adjusted to pH = 2.3 to 5.0 is brought into contact with the surface of the metal material for 1 to 60 seconds, washed with water and dried to obtain 0.02 to 1 mmol / m. includes ² of Cr and 0.02～1Mmol / m ² of Ti and / or Zr, forming a conversion coating having a thickness of 1 to 100 nm.
[Selection figure] None

Description

  The present invention relates to a novel metal surface chemical conversion treatment liquid and surface chemical conversion treatment method for imparting excellent corrosion resistance and coating film adhesion to a metal surface. The chemical conversion treatment liquid of the present invention does not contain harmful hexavalent chromium, and can impart high corrosion resistance to the metal surface. In particular, the chemical conversion treatment liquid of the present invention can impart high corrosion resistance to aluminum and aluminum alloy materials typified by aluminum die cast materials, and zinc and zinc alloy materials typified by zinc die cast materials and galvanized metal materials. . Furthermore, there is little generation | occurrence | production of the sludge (precipitate) in a process liquid, and there are few environmental impacts.

  Chemical conversion treatment has long been used for the purpose of imparting corrosion resistance and paint adhesion for metals. First, the chemical conversion treatment of an aluminum-based material, to which the present invention is suitable, will be described. In general, the surface treatment liquid for aluminum or aluminum alloy material can be roughly classified into a chromate type and a non-chromate type. Typical examples of the chromate type treatment liquid include a chromate chromate chemical conversion treatment liquid and a phosphoric acid chromate chemical conversion treatment liquid.

  First, the chromate chromate conversion treatment solution will be described. The chromate chromate conversion treatment solution was put into practical use around 1950 and is still widely used for surface treatment of aircraft materials, building materials, automobile parts and the like. This chromate chromate chemical conversion treatment liquid contains chromic acid and a fluoride as a reaction accelerator as main components, and forms a chemical conversion film containing hexavalent chromium on the surface of the metal material.

  Moreover, the phosphoric acid chromate chemical conversion treatment liquid is based on the invention disclosed in US Pat. No. 2,438,877 (Patent Document 1), containing chromic acid, phosphoric acid and hydrofluoric acid as main components, and on the surface of the metal material. A chemical conversion film mainly composed of hydrated chromium phosphate is formed. Since this chemical conversion film does not contain hexavalent chromium, it is still widely used for coating base treatment of beverage can lids.

  Although the chemical conversion film formed with such a chromate type surface treatment liquid has excellent corrosion resistance and coating film adhesion, it contains harmful hexavalent chromium in the treatment liquid. It is desired to use a treatment solution that does not contain any valent chromium. A great number of inventions have been devised for the surface treatment liquid and the surface treatment method that do not contain hexavalent chromium, but there are not so many techniques that can actually be industrialized.

  A typical invention of a non-chromate type surface treatment solution containing no chromium is a treatment solution disclosed in JP-A-52-131937 (Patent Document 2). This surface treatment solution is an acidic aqueous coating solution containing zirconium or titanium or a mixture thereof, phosphoric acid and fluoride, and having a pH of about 1.5 to 4.0. When the surface of the metal material is treated using this surface treatment liquid, a chemical conversion film mainly composed of an oxide of zirconium or titanium is formed on the metal surface. This non-chromate type surface treatment liquid has the advantage of not containing hexavalent chromium, and is actually widely used for the surface treatment of aluminum DI cans used for beverage cans such as beer. Generally, it is a category of a non-chromium chemical conversion agent called zirconium-based or titanium-based.

  In the treatment method disclosed in JP-A-57-41376 (Patent Document 3), one or more of a titanium salt or a zirconium salt and one or two of an imidazole derivative are formed on the surface of aluminum, magnesium and an alloy thereof. Surface treatment is performed using an aqueous solution containing seeds or more and an oxidizing agent such as nitric acid, hydrogen peroxide, or potassium permanganate. The oxidizing agent promotes the precipitation of titanium and zirconium. It is in the category of the improvement technology of the above-mentioned non-chromium chemical conversion agent called zirconium-based or titanium-based.

  Non-chromate type treatment liquids further include those disclosed in the following patent publications. JP-A-56-136978 (Patent Document 4) is characterized by comprising an aqueous solution containing a vanadium compound and at least one compound selected from the group consisting of a titanium salt, a zirconium salt and a zinc salt. A chemical conversion solution is disclosed. This is a composite of vanadium and zirconium and titanium.

  Japanese Unexamined Patent Publication No. 2000-199077 (Patent Document 5) discloses an acidic metal surface treatment liquid containing a metal acetolacetonate, at least one compound selected from a water-soluble inorganic titanium compound and a water-soluble inorganic zirconium compound. ing. This treatment liquid uses vanadyl acetate, zirconium acetate, zinc acetate or the like, and is a composite of metal acetate with zirconium and titanium.

  Japanese Patent Laid-Open No. 5-5185 (Patent Document 6) discloses that one or two ions selected from the group consisting of tungstate ions and molybdate ions are 0.1 to 3.0 g / l, hexavalent chromium ions 0 A chromate treatment solution having a pH of 1.0 to 3.0 containing 40 to 5.0 g / l, phosphate ions of 5.0 to 30.0 g / l and free fluorine ions of 0.05 to 2.0 g / l A surface treatment method for aluminum has been devised, characterized by spraying the surface of aluminum or aluminum alloy having a clean surface by heating to ~ 60 ° C for 0.5 to 3 seconds. It is in a category called tungsten or molybdenum.

  In JP-A-11-36082 (Patent Document 7), 0.01 to 50 g / L of permanganic acid or a salt thereof, and 0.01 to 20 g / L of a water-soluble titanium compound and a water-soluble zirconium compound are selected. And a surface treatment solution for light metal or light alloy materials characterized by having a pH of 1.0 to 7.0. It is in a category called manganese-titanium or manganese-zirconium system.

  Japanese Patent Application Laid-Open No. 2004-232047 (Patent Document 8) contains hexacyanoate ion and one or more metal ions selected from the group consisting of Ti, V, Mn, Fe, Co, Zr, Mo and W. However, a highly corrosion-resistant chromium-free chemical conversion coating agent for aluminum and aluminum alloys characterized by not containing chromium ions is described. Elements other than cobalt are the elements mentioned in the above invention. The claims are wide and the novelty of past inventions is scarce.

  Japanese Patent Laid-Open No. 2001-247777 (Patent Document 9) discloses that a coating formed by surface treatment on a metal surface includes a plurality of metal elements, and at least one of the metal elements has a plurality of valences. A featured chromium-free metal surface treatment composition has been devised. Actually, the metal element is at least two of Mg, Al, Ti, V, Mn, Fe, Co, Ni, Cu, Zn, Sr, Nb, Y, Zr, Mo, In, Sn, Ta, and W. Although it is a chromium-free metal surface treatment composition characterized by being more than one kind, the claim is too wide, the actual treatment method is unclear, and the novelty is less than that of past inventions. It is thought that the conventional zirconium series, titanium series, vanadium series, tungsten series, molybdenum series, and manganese series are expanded.

  WO03 /: 074761 A1 (Patent Document 10) includes (1) Compound A containing at least one metal element selected from (1) Hf (IV), Ti (IV) and Zr (IV), (2) A fluorine-containing compound in an amount sufficient to cause at least 5 times the molar concentration of fluorine in the composition to be present in the composition, (3) at least one selected from the group of alkaline earth metals Aluminum, aluminum alloy, magnesium or magnesium alloy containing metal ion B, (4) at least one metal ion C selected from Al, Zn, Mg, Mn and Cu, and (5) nitrate ion A surface treatment composition has been devised. In a broad sense, this treatment liquid is on an extension line of zirconium and titanium.

  Furthermore, Japanese Patent Application Laid-Open No. 2003-313679 (Patent Document 11) discloses a treatment with a non-chromium metal surface treatment agent comprising a water-soluble zirconium compound and / or a water-soluble titanium compound (1) and an organic phosphonic acid compound (2). A non-chromium metal surface treatment method comprising: a step (A) for treating a product; and a step (B) for treating the treatment target subjected to the step (A) with an aqueous solution of tannin (3). The content of the zirconium compound and / or the water-soluble titanium compound (1) is 40 to 1000 ppm on a mass basis as the amount of zirconium and / or titanium, and the content of the organic phosphonic acid compound (2) is on a mass basis. The non-chromium metal surface treatment agent has a pH of 1.6 to 4.0, and the content of the tannin (3) in the aqueous solution is Non-chromium metal surface treatment method characterized have been devised that criteria is 400～10000Ppm. In a broad sense, this treatment liquid is on an extension line of zirconium and titanium.

  In the invention of JP-A-2003-313681 (Patent Document 12), a non-chromium metal surface treatment agent comprising a water-soluble zirconium compound and / or a water-soluble titanium compound (1) and an organic phosphonic acid compound (2) is treated. A non-chromium metal surface treatment method comprising: a step (A) for treating a product; and a step (B) for treating the workpiece subjected to the step (A) with an aqueous solution of tannin (3). The acid compound (2) is a compound in which a phosphorus atom constituting a phosphonic group is bonded to a carbon atom, and the content of the water-soluble zirconium compound and / or the water-soluble titanium compound (1) is zirconium and / or titanium. The amount of the organic phosphonic acid compound (2) is 20 to 800 ppm on a mass basis, and the content of the organic phosphonic acid compound (2) is 10 to 500 ppm on a mass basis. The aqueous solution of 3) has a tannin concentration of 300 to 8000 ppm by mass, and the non-chromium metal surface treatment agent has a pH of 1.6 to 4.0, and is used for producing a thermoplastic polyester resin-coated metal plate. A non-chromium metal surface treatment method has been devised. As before, it is on the extension line of zirconium and titanium.

  On the other hand, in a surface treatment liquid and a treatment method for imparting corrosion resistance and paint adhesion to an aluminum-containing metal material, a method using a water-soluble resin is disclosed in Japanese Patent Application Laid-Open No. 61-91369 (Patent Document 13). Japanese Laid-Open Patent Publication No. 1-172406 (Patent Document 14), Japanese Laid-Open Patent Publication No. 1-177379 (Patent Document 15), Japanese Laid-Open Patent Publication No. 1-177380 (Patent Document 16), Japanese Laid-Open Patent Publication No. 2-608 (Patent Document 17). JP-A-2-609 (Patent Document 18) and the like are disclosed. In these conventional surface treatment liquids and surface treatment methods, a metal surface is treated with a solution containing a derivative of a polyhydric phenol compound. There is also an invention of Japanese Patent No. 2771110 (Patent Document 19) which discloses a treatment liquid and method containing a derivative of this polyhydric phenol compound. This is in a category called a resin system or a resin-metal composite system.

  The invention of Japanese Patent Application Laid-Open No. 2001-303267 (Patent Document 20) includes a zirconium compound, fluorine ions, a water-soluble resin and an aluminum salt, and the concentration of the zirconium compound is 100 to 100,000 ppm in terms of zirconium ions, and the fluorine ion concentration. Has been devised, a non-chromium anti-rust treatment agent for aluminum, characterized in that the non-volatile content concentration of the water-soluble resin is 100 ppm to 100,000 ppm, and the concentration of the aluminum salt is 10 ppm to 10,000 ppm in terms of aluminum ions. . This is also a combination of the aforementioned resin system and zirconium system.

  On the other hand, a chemical conversion liquid using trivalent chromium that is not completely non-chromium but does not contain harmful hexavalent chromium has been devised. Japanese Patent No. 3333611 (Patent Document 21) discloses at least one ion (B) selected from an acid ion (A) having an acid group containing phosphorus, a trivalent chromium ion, and a compound ion having trivalent chromium. And a hexavalent chromium-free chemical conversion surface treatment agent for aluminum and aluminum alloys, characterized in that it contains at least one fluorine compound (C) selected from the group consisting of fluoride, complex fluoride and hexavalent chromium ions Has been devised. It belongs to the category called trivalent chromium.

  JP 2000-332575 A (Patent Document 22) discloses a chemical conversion treatment agent used after treating a substrate made of aluminum or an aluminum alloy at 10 to 70 ° C. for 5 seconds to 5 minutes using an acidic aqueous solution. The acidic aqueous solution is (a) at least one selected from the group consisting of a metal salt selected from Fe, Ni, Co, Mo and Ce and a metal acid salt, 0.01 to 5% by mass of the acidic aqueous solution, and (B) An acidic aqueous solution containing an inorganic acid having a pH of 2 or less, and the chemical conversion treatment agent is (c) Zr and / or Ti containing 0.001 to 1% by mass of the chemical conversion treatment agent, and (d) trivalent. There has been devised a chemical conversion treatment agent characterized by containing chromium ions or a salt thereof in an amount of 0.1 to 1000 ppm of the chemical conversion treatment agent and (e) a fluoride. Basically, it is imitating the above-mentioned Patent No. 3333611 and is not novel, but it belongs to trivalent chromium as a classification.

  JP-A-2004-010937 (Patent Document 23) includes (A) trivalent chromium ion, (B) Mo, W, Ti, Zr, Mn, Tc, Fe, Ru, Co, alkaline earth metal, At least one of the group consisting of Ni, Pd, Pt, Sc, Y, V, Nb, Ta, Cu, Ag, Au, (C) one of the group consisting of chlorine, fluorine, sulfate ion, nitrate ion And (D) forming a rust preventive film with a liquid composition containing at least one species selected from the group consisting of oxygen acids, oxyacid salts, anhydrides and phosphorus compounds of phosphorus. A method for forming a rust film has been devised. This invention is basically an extension of the scope of claims by imitating the above-mentioned Japanese Patent No. 3333311 and has a problem in novelty, but belongs to the trivalent chromium system as a classification.

  Japanese Patent Application Laid-Open No. 2004-3019 (Patent Document 24) discloses a method for producing a chemical conversion film that does not contain hexavalent chromium and that provides at least corrosion resistance due to yellow chromate treatment containing hexavalent chromium. Treated with a solution of one trivalent chromium chelate complex, and the trivalent chromium of the chelate complex is present in the solution at a concentration of 5 to 100 g / l, and the trivalent chromium chelate complex is a trivalent chromium-fluoro complex A method has been devised that has a faster ligand substitution rate than the fluoride substitution rate in. Although this invention also has a problem in novelty, it belongs to trivalent chromium as a classification.

  Also, the same technology is often used for zinc die casting. Japanese Patent No. 3597542 (Patent Document 25) discloses a substantially coherent conversion layer of hexavalent chromium and trivalent chromium on zinc or a zinc alloy, which includes silicate, cerium, aluminum and boric acid. Providing about 100 to 1000 hours of corrosion protection in the salt spray test according to DIN 50021 SS or ASTM B 117-73 in the absence of further components, such as salt, until the first erosion according to DIN 50961 Chapter 10; It is clear, transparent and essentially colorless, has a multicolored gloss, has a layer thickness of about 100 to 1000 nm, is hard and has good adhesion and is wiped Invention relating to a coating of trivalent chromium relating to a coating on zinc called a conversion layer characterized by It is mentioned.

The above conventional inventions can be summarized as follows: (1) zirconium or titanium-based and derivatives thereof, (2) vanadium, molybdenum, tungsten, cobalt-containing systems, (3) organic systems containing tannic acid or water-soluble resins, 4) Organic / inorganic composite systems combining zirconium and resin, and (5) systems containing trivalent chromium.
Among these, the zirconium series belonging to (1) exhibits sufficient performance in applications such as painting bases, cold rolled materials with a uniform aluminum surface, and applications where the requirement for corrosion resistance is not strict. Industrialization has also been made. However, these films are not formed and painted on non-uniform surface properties such as aluminum die-cast materials (a large number of surface segregated materials, non-uniformly thick aluminum oxide film, etc.) In applications that are used in bare specifications, the corrosion resistance is actually inferior to that of chromate films. (2) Vanadium, molybdenum, tungsten, cobalt-containing systems, (3) Organic systems containing tannic acid and water-soluble resins, (4) Aluminum die-casting even when using organic / inorganic composite systems combining zirconium and resins It is not enough to treat the material and evaluate the corrosion resistance with bare specifications.

  In addition, among the above-mentioned broadly classified technologies, the corrosion resistance performance is the most excellent. (5) In the trivalent chromium system, the corrosion resistance performance may be sufficiently obtained. is there. For example, Japanese Patent No. 3333311 (Patent Document 21) contains an acid ion having an acid group containing phosphorus. For this reason, when aluminum is continuously treated and aluminum is mixed into the treatment liquid, aluminum phosphate sludge is formed. To prevent this, the pH must be lowered and controlled. In addition, in the case of JP 2000-332575 A (Patent Document 22), it is an acidic aqueous solution having a pH of 2 or less, and a very strong etching reaction occurs when an aluminum material is brought into contact. For this reason, the film to be formed becomes porous, resulting in insufficient corrosion resistance, and a large amount of etched aluminum accumulates in the processing liquid, which causes sludge generation. Japanese Unexamined Patent Application Publication No. 2004-010937 (Patent Document 23) also has a problem of sludge generation because it contains a phosphorus compound. Furthermore, in Japanese Patent No. 3559742 or JP 2004-3019 A (Patent Document 24) related thereto, trivalent chromium in the treatment solution has a concentration of 5 to 100 g / l. It is a considerably high concentration treatment liquid, and there are problems such as high costs in actual industrialization and high load on subsequent washing water (treatment liquid in the previous process). Yes. Further, in the present invention, a film is defined, and the film thickness is slightly thick, from 100 nm to 1000 nm. In general, when the film thickness is increased, the corrosion resistance is improved, but the paint adhesion is deteriorated. In addition, the fact that the film thickness is thick means that the cost is increased by itself.

  As described above, when the conventional non-chromate type surface treatment solution is used, there remains a problem in the corrosion resistance of the formed chemical conversion film. In particular, it is used for an aluminum die-cast material used as a material for parts of aircraft, automobiles, and home appliances, and cannot exhibit sufficient corrosion resistance in the case of bare specifications (the coating is not made with a chemical conversion film alone). In addition, the trivalent chromium system has problems in industrial operation and processing costs.

Therefore, aluminum or aluminum which does not contain hexavalent chromium in the treatment liquid at present, is excellent in operability and economy, and can provide sufficient corrosion resistance to the bare specification of the aluminum die cast material. The fact is that a chemical conversion treatment solution and a processing method for alloy materials have not been established.
U.S. Pat. No. 2,438,877 JP 52-131937 A JP-A-57-41376 JP-A-56-136978 JP 2000-199077 A JP-A-5-5185 JP 11-36082 A JP 2004-232047 A JP 2001-247777 A WO03 / 074761 A1 JP 2003-313679 A JP 2003-313681 A JP-A-61-91369 JP-A-1-172406 JP-A-1-177379 JP-A-1-177380 JP-A-2-608 JP-A-2-609 Japanese Patent No. 2771110 JP 2001-303267 A Japanese Patent No. 3333311 JP 2000-332575 A JP 2004-010937 A JP 2004-3019 A Japanese Patent No. 35597542

  The present invention is for solving the above-mentioned problems of the prior art, and specifically provides excellent corrosion resistance to the metal material surface. Especially when it is applied to aluminum die-cast material or zinc die-cast material, it is given bare corrosion resistance equivalent to chromate, and has appropriate paint adhesion. An object of the present invention is to provide a chemical conversion treatment solution and a chemical conversion treatment method for metal materials that can control industrial waste such as sludge, can be easily controlled, and are economically inexpensive.

  The present inventors diligently studied means for solving the above-described problems of the prior art. As a result, it contains at least one compound selected from a specific water-soluble trivalent chromium compound, a specific water-soluble titanium compound and a water-soluble zirconium compound, a specific water-soluble nitrate compound, and a specific water-soluble aluminum compound, The inventors have found an acidic aqueous solution in which a specific fluorine compound is contained in the liquid and the pH of the processing liquid is in a specific range, or a specific chemical conversion liquid to which a specific oxidizing agent is added. In addition, when the specific chemical conversion treatment liquid is brought into contact with the surface of the metal material under specific conditions, a specific film is formed, and a surface treatment method capable of imparting excellent corrosion resistance is found and continuously operated. In addition, the inventors have found that generation of sludge and the like is suppressed by specifying the composition and processing conditions, and have completed the present invention.

The chemical conversion treatment liquid for metal material of the present invention comprises a component (A) composed of at least one water-soluble trivalent chromium compound, and a component (B) composed of at least one selected from a water-soluble titanium compound and a water-soluble zirconium compound. And an aqueous treatment liquid containing at least one component (C) composed of a water-soluble nitrate compound and a component (D) composed of at least one water-soluble aluminum compound. A treatment liquid further comprising a component (E) comprising at least a fluorine compound ,
The water-soluble trivalent chromium compound-containing component (A) has a metal chromium equivalent content (CA) of 0.1 to 20 mmol / liter, and the water-soluble titanium compound and / or water-soluble zirconium compound-containing component (B) The total content (CB) in terms of metal titanium and metal zirconium is 0.1 to 10 mmol / liter, and the cation equivalent content (CC) of the water-soluble nitrate compound-containing component (C) is 0.2 to 40 mmol. The fluorine equivalent content (CE) of the fluorine compound-containing component (E) is represented by the following formula:
(CA × 2 + CB × 4 + CD × 2) ≦ CE ≦ (CA × 4 + CB × 7 + CD × 4)
[However, in the above formula, CA, CB, CD and CE are as defined above]
And the pH of the treatment liquid is controlled to be in the range of 2.3 to 5.0.
In the chemical conversion liquid for metal material of the present invention, it is preferable that the surface treatment liquid further contains an oxidizing agent (F).
In the chemical conversion liquid for metal material of the present invention, the water-soluble trivalent chromium compound-containing component (A) preferably contains at least one selected from chromium nitrate, chromium sulfate, and chromium fluoride.
In the chemical conversion liquid for metal material of the present invention, the component (B) comprising the water-soluble titanium compound and / or the water-soluble zirconium compound is titanium sulfate, titanium oxysulfate, ammonium ammonium sulfate, titanium nitrate, titanium oxynitrate, nitric acid. Titanium ammonium, titanium sulfate, titanium oxysulfate, ammonium titanium sulfate, titanium nitrate, titanium oxynitrate, ammonium ammonium nitrate, fluorotitanic acid, fluorotitanium complex, zirconium sulfate, zirconium oxysulfate, zirconium ammonium sulfate, zirconium nitrate, zirconium oxynitrate , Zirconium ammonium nitrate, zirconium sulfate, zirconium oxysulfate, zirconium ammonium sulfate, zirconium nitrate, zirconium oxynitrate, ammonium zirconium nitrate, fluo Zirconic acid, fluorozirconium complex salt, titanium lactate, titanium acetylacetonate, titanium triethanolamate, titanium octyl glycolate, tetraisopropyl titanate, tetranormal butyl titanate, zirconyl acetate, zirconyl lactate, zirconium tetraacetylacetonate, zirconium tryptoxy It is preferable to include at least one selected from acetylacetonate, tetranormal butoxyzirconium, and tetranormalpropoxyzirconium.
In the chemical conversion liquid for metal material of the present invention, the water-soluble nitrate compound-containing component (C) preferably contains at least one selected from magnesium nitrate, calcium nitrate, strontium nitrate, manganese nitrate, and cerium nitrate.
In the chemical conversion liquid for metal material of the present invention, the water-soluble aluminum compound-containing component (D) preferably contains at least one selected from aluminum nitrate, aluminum sulfate, and aluminum fluoride.
In the chemical conversion liquid for metal material of the present invention, the fluorine compound-containing component (E) is hydrofluoric acid, ammonium fluoride, chromium fluoride, fluorotitanic acid, fluorotitanium complex salt, fluorozirconic acid, fluorozirconium complex salt, It is preferable to include at least one selected from magnesium fluoride and aluminum fluoride.
In the chemical conversion liquid for metal material of the present invention, the oxidizing agent (F) does not contain at least one selected from a peroxo acid compound and a nitrous acid compound, and its content is 0.1 to 15 mmol / liter. It is preferable.
In the chemical conversion liquid for metal material of the present invention, the metal material is preferably selected from aluminum and aluminum alloy materials, zinc and zinc alloy materials, and galvanized metal materials.
The method for chemical conversion treatment of the metal material surface of the present invention is as follows: * The metal chemical conversion treatment solution of the present invention is heated to a temperature of 30 to 70 ° C., and is brought into contact with a clean metal material surface for 1 to 600 seconds. Thereafter, the surface of the metal material is washed with water and dried, and 0.02 to 1 mmol / m ² of chromium and 0.02 to 1 mmol / m ² of titanium and / or zirconium are included on the surface of the metal material, A chemical conversion film having a film thickness of 100 nm is formed.
In the chemical conversion treatment method for the surface of the metal material of the present invention, it is preferable to perform deionization cleaning on the surface of the metal material washed with water between the washing with water and drying.
In the chemical conversion treatment method for a metal material surface according to the present invention, the clean metal material surface is deoxidized by subjecting the surface of the metal material to deoxydizing treatment with an aqueous treatment liquid having an acid or a redox agent. It is preferable that
In the chemical conversion treatment method for a metal material surface according to the present invention, the metal material is preferably selected from aluminum and an aluminum alloy material, zinc and a zinc alloy material, and a galvanized metal material.
The chemical conversion treatment method for the metal material surface of the present invention comprises a component (A) comprising at least one water-soluble trivalent chromium compound, and a component comprising at least one selected from a water-soluble titanium compound and a water-soluble zirconium compound (B ), A component (C) composed of at least one water-soluble nitrate compound, and a component (D) composed of at least one water-soluble aluminum compound, one further metallic material for chemical conversion treatment liquid containing a component made of a fluorine compound (E), heated to a temperature of 30 to 70 ° C., it is contacted 1-600 seconds clean metal surface, this When the composition of the chemical conversion treatment liquid has a metal chromium equivalent content (CA) of the water-soluble trivalent chromium compound-containing component (A) of 0.1 to 20 mmol / liter, The total content (CB) in terms of metal titanium and metal zirconium of the soluble titanium compound and / or water-soluble zirconium compound-containing component (B) is 0.1 to 10 mmol / liter, and the water-soluble nitrate compound-containing component (C) The cation-equivalent content (CC) is 0.2 to 40 mmol / liter, the water-soluble aluminum compound (D) content (CD) as aluminum is 0.2 to 40 mmol / liter, and the fluorine The fluorine equivalent content (CE) of the compound-containing component (E) is represented by the following formula:
(CA × 2 + CB × 4 + CD × 2) ≦ CE ≦ (CA × 4 + CB × 7 + CD × 4)
[However, in the above formula, CA, CB, CD and CE are as defined above]
And the pH of the chemical conversion treatment liquid is controlled to be within the range of 2.3 to 5.0, thereby preventing generation of sludge in the chemical conversion liquid, and the metal material Then, a chemical conversion film having excellent corrosion resistance is formed on the surface of the metal material , and then the metal material surface is washed with water and dried, and 0.02 to 1 mmol / m ² of chromium and 0.02 to 0.02 on the metal material surface. A chemical conversion film having a film thickness of 1 to 100 nm containing 1 mmol / m ² of titanium and / or zirconium is formed.
In the chemical conversion treatment method for the surface of the metal material of the present invention, it is preferable to perform deionization cleaning on the surface of the metal material washed with water between the washing with water and drying.
In the chemical conversion treatment method for a metal material surface according to the present invention, the clean metal material surface is deoxidized by subjecting the surface of the metal material to deoxydizing treatment with an aqueous treatment liquid having an acid or a redox agent. It is preferable that
In the chemical conversion treatment method for a metal material surface according to the present invention, the clean metal material is preferably selected from aluminum and an aluminum alloy material, zinc and a zinc alloy material, and a galvanized metal material.

  According to the chemical conversion treatment solution and the chemical conversion treatment method according to the present invention, excellent corrosion resistance can be imparted to a metal surface, for example, a surface of aluminum or an aluminum alloy material, without using harmful hexavalent chromium. Furthermore, when applied to an aluminum die-cast material, it can provide corrosion resistance equivalent to chromate under bare specifications, and also has excellent paint adhesion, and industrial waste such as sludge when industrialized and operated. It has an excellent effect that it can be easily controlled.

  The chemical conversion liquid for metal materials according to the present invention comprises a water-soluble trivalent chromium compound-containing component (A), a water-soluble titanium compound and / or a water-soluble zirconium compound-containing component (B), and a water-soluble nitrate compound-containing component (C). The water-soluble aluminum compound-containing component (D) is contained, the liquid contains a fluorine compound component (E) composed of at least one fluorine compound, and the pH of the treatment liquid is 2.3-5. The acidic aqueous solution is controlled within a range of 0.0, and the chemical conversion treatment liquid of the present invention may contain an oxidant component (F). The operation of each component will be described below.

  The water-soluble trivalent chromium compound-containing component (A) of the chemical conversion treatment solution for metals of the present invention is an essential component and greatly affects the corrosion resistance of the obtained chemical conversion treatment metal material. In order to contain the trivalent chromium compound-containing component (A), at least one selected from chromium nitrate, chromium sulfate, and chromium fluoride can be used. Content of a component (A) exists in the range of 0.1-20 mmol / liter in conversion of chromium, Preferably, it is the range of 0.4-4 mmol / liter. If the content of the component (A) is less than 0.1 mmol / liter, the chromium content in the resulting chemical conversion film will be insufficient. Moreover, when it exceeds 20 mmol / liter, cost will become high and will become economically disadvantageous.

  The component (B) consisting of at least one compound selected from a water-soluble titanium compound and a water-soluble zirconium compound in the chemical conversion treatment solution for metals of the present invention is also an essential component, and the corrosion resistance of the resulting chemical conversion treatment metal material Greatly affects. In order to contain the water-soluble titanium compound and / or the water-soluble zirconium compound (B), a water-soluble inorganic titanium compound and a water-soluble inorganic zirconium compound, such as titanium sulfate, titanium oxysulfate, ammonium ammonium sulfate, titanium nitrate, titanium oxynitrate , Titanium ammonium nitrate, Titanium sulfate, Titanium oxysulfate, Titanium ammonium sulfate, Titanium nitrate, Titanium oxynitrate, Titanium ammonium nitrate, Fluorotitanic acid, Fluorotitanium complex, Zirconium sulfate, Zirconium oxysulfate, Zirconium ammonium sulfate, Zirconium nitrate, Oxy Zirconium nitrate, ammonium zirconium nitrate, zirconium sulfate, zirconium oxysulfate, ammonium zirconium sulfate, zirconium nitrate, zirconium oxynitrate, zirconium nitrate Muammonium, fluorozirconic acid, and fluorozirconium complex salts, and water-soluble organic titanium compounds and water-soluble organic zirconium compounds such as titanium lactate, titanium acetylacetonate, titanium triethanolamate, titanium octyl glycolate, tetraisopropyl titanate One or more selected from tetranormal butyl titanate, zirconyl acetate, zirconyl acetate, zirconium tetraacetylacetonate, zirconium tryptoxyacetylacetonate, tetranormalbutoxyzirconium, and tetranormalpropoxyzirconium can be used. The content of the component (B) is required to be within a range of 0.1 to 10 mmol / liter of titanium or zirconium equivalent, and preferably 0.4 to 4 mmol / liter. When the Ti and / or Zr equivalent content of the component (B) is less than 0.1 mmol / liter, the adhesion of zirconium or titanium becomes insufficient. Moreover, when it exceeds 10 mmol / liter, the density | concentration in a chemical conversion liquid will be high, cost will become high, and it will become economically disadvantageous.

  The water-soluble nitrate compound-containing component (C) in the metal chemical conversion treatment liquid of the present invention is also an essential component, and affects the final corrosion resistance because it affects the uniformity of the formed film. The component (C) has an effect of suppressing excessive etching at the chemical conversion liquid and material interface during the treatment process, and it is considered that the film becomes uniform. In order to contain the water-soluble nitrate compound-containing component (C), at least one of magnesium nitrate, calcium nitrate, strontium nitrate, manganese nitrate, and cerium nitrate can be used. The chaotic equivalent content CC of the water-soluble nitrate compound-containing component (C) needs to be in the range of 0.2 to 40 mmol / liter in terms of nitrate cations, such as magnesium and / or calcium cations. Preferably, it is 4-30 mmol / liter. When the content of the component (C) is less than 0.2 mmol / liter, the effect of uniformizing the film becomes insufficient. Moreover, when it exceeds 40 mmol / liter, the density | concentration in a chemical conversion liquid will be high and will cause sludge generation | occurrence | production.

  The water-soluble aluminum compound-containing component (D) in the chemical conversion treatment solution for metals of the present invention is also an essential component, and like the magnesium and calcium cations, the chemical conversion solution excessively etches the metal material surface. There is an effect to prevent. In order to contain the water-soluble aluminum compound-containing component (D), aluminum nitrate, aluminum sulfate, and aluminum fluoride can be used. Further, when aluminum or an aluminum alloy material is processed continuously, metallic aluminum as a material is eluted into the chemical conversion solution by etching accompanying the chemical conversion reaction. For this reason, if the treatment liquid is controlled well, it is not necessary to forcibly add (supplement) the aluminum compound during continuous operation. The content in terms of aluminum of this component (D) needs to be in the range of 0.2 to 40 mmol / liter, and preferably 4 to 20 mmol / liter. When the content of component (D) is less than 0.2 mmol / liter, the effect of uniforming the film is insufficient. Moreover, when it exceeds 40 mmol / liter, the density | concentration in a chemical conversion liquid will be high and will cause sludge generation | occurrence | production.

The fluorine compound-containing component (E) in the chemical conversion solution for metals of the present invention is a very important essential component. The fluorine compound influences the etching of the material, but in the present invention, it has been found that the component (E) has a great influence on the corrosion resistance of the obtained chemical conversion-treated metal material. Moreover, it discovered that generation | occurrence | production of sludge could be suppressed when operating continuously by controlling appropriately the quantity of this component (E). Some of the prior art mentions the inclusion of fluorine compounds, which puts emphasis on the etching action. To contain the fluorine compound synthesis component (E), hydrofluoric acid, ammonium fluoride, chromium fluoride, fluorotitanic acid, fluorotitanium complex salt, fluorozirconic acid, fluorozirconium complex salt, magnesium fluoride, aluminum fluoride, etc. One or more of these can be used. Of these, hydrofluoric acid and ammonium fluoride are extremely important, and the final adjustment of the content is performed by these. It is preferable that the fluorine conversion content (CE) of the component (E) in the chemical conversion liquid, that is, the total fluorine amount is within the concentration range of the following formula. That is, the concentration CA of the water-soluble trivalent chromium compound component, the concentration CB of at least one compound component (B) selected from the water-soluble titanium compound and the water-soluble zirconium compound, and the concentration CD of the water-soluble aluminum compound component (D) And must be controlled to satisfy the following equation.
(CA × 2 + CB × 4 + CD × 2) ≦ CE ≦ (CA × 4 + CB × 7 + CD × 4)
When CE is less than the minimum concentration shown in the formula, the corrosion resistance of the formed chemical conversion film is insufficient, and sludge is generated during continuous operation. On the other hand, when the maximum CE value is exceeded, the etching power of the resulting chemical conversion solution becomes strong, and the deposition efficiency of the film becomes poor. Further, the CE value is more preferably within the following range.
(CA × 3 + CB × 6 + CD × 2) ≦ CE ≦ (CA × 3 + CB × 6 + CD × 4)

  The pH of the chemical conversion treatment solution for metals of the present invention is also extremely important and has an appropriate range. In the chemical conversion treatment liquid of the present invention, it is important to control the pH within the range of 2.3 to 5.0. If the pH is less than 2.3, the etching power of the obtained chemical conversion solution becomes strong, and the deposition efficiency of the film becomes insufficient. Moreover, when pH exceeds 5.0, generation | occurrence | production of sludge increases at the time of continuous operation. A more preferable pH range is 3.0 to 4.0. The pH adjustment method is not particularly limited, but it is preferably adjusted using nitric acid, hydrofluoric acid, ammonium hydrogen carbonate, aqueous ammonia, or the like.

  You may further add an oxidizing agent (F) to the chemical conversion liquid for metals of this invention. The oxidizing agent has an effect of accelerating the chemical film formation reaction, increasing the film production efficiency, making the film more dense and improving the corrosion resistance. As the oxidizing agent, it is preferable to use a peroxo acid compound and / or a nitrous acid compound. Moreover, it is preferable that the content is 0.1-15 mmol / liter. The effect of promoting the formation of chemical conversion film appears at 0.1 mmol / liter or more. Moreover, even if it exceeds 15 mmol / liter, there is no particular problem, but the concentration is high, and the cost is increased, which may be economically disadvantageous.

In the surface treatment method of the present invention, the above-mentioned chemical conversion treatment solution for metals is heated to a temperature of 30 to 70 ° C., brought into contact with a clean metal material surface for 1 to 600 seconds, then washed with water, and if necessary. subjecting deionized washed and subsequently dried, on the surface, depositing a film containing titanium and / or zirconium chromium and 0.02~1mmol / m ² of 0.02~1mmol / m ^2, the film The thickness is controlled to 1 to 100 nm. The temperature of the treatment is an important factor that affects the reactivity. Below 30 ° C., the reactivity is poor and it is inappropriate for industrialization. Moreover, when it exceeds 70 degreeC, since stability of a process liquid is impaired, it is unpreferable. The surface of the material that contacts the chemical conversion solution must be clean. This is because film formation becomes non-uniform when oil or the like is adhered. There are no particular restrictions on the pretreatment method to be cleaned, as long as it has been cleaned by ordinary solvent degreasing, alkali degreasing, acidic degreasing, alkaline etching, and subsequent pretreatment such as acid desmutting and shot blasting. Good. However, it is more preferable that the surface oxide be deoxydized with a water-soluble treatment solution having an acid or redox agent, followed by chemical conversion treatment. The treatment time for contact with the chemical conversion treatment liquid is in the range of 1 to 600 seconds. This is the time required to obtain the following adhesion amount in combination with the processing temperature and concentration. Generally, in less than 1 second, the reaction is insufficient and film formation is not complete. Moreover, even if it exceeds 600 seconds, there is no special advantage and industrial productivity falls on the contrary. The contact method may be a dipping method, a spray method, a flow coating method, or the like. Thereafter, washing with water is performed, which is performed in order to rinse off unreacted components. Moreover, when using a chemical conversion treatment surface as a coating base, the hardness component etc. in a water washing liquid may have a bad influence, In this case, it is preferable to give a deionization washing | cleaning. Further, drying is performed. Drying is performed in order to volatilize moisture, and the drying method and drying temperature are not particularly limited, but warm air drying is preferable, and the drying temperature is preferably in the range of 80 to 140 ° C. from an industrial viewpoint. . The surface of the treated material must conversion coating is formed comprising titanium and / or zirconium chromium and 0.02~1mmol / m ² of 1 mmol / m ² from 0.02. When the chromium content is less than 0.02 mmol / m ² and the titanium and / or zirconium content is less than 0.02 mmol / m ² , the amount of chemical conversion film is insufficient and the corrosion resistance is insufficient. In addition, when the chromium content exceeds 1 mmol / m ² and the titanium and / or zirconium content exceeds 1 mmol / m ² , the corrosion resistance of the resulting chemical conversion film is not particularly problematic, but the processing cost is high. It becomes economically disadvantageous. It is important that the film thickness of the chemical conversion film is in the range of 1 to 100 nm.

  The metal material to be brought into contact with the chemical conversion solution for metal is not particularly limited, but aluminum or an aluminum alloy material, that is, an aluminum-containing metal material is suitable. Moreover, it is difficult to impart sufficient corrosion resistance in other inventions, and the material to which the present invention is most effectively applied is an aluminum die-cast material. In particular, when it is applied to an aluminum die-cast material widely used for component materials, for example, JIS-ADC-12, very high utility is exhibited. Moreover, it is suitable also for the metal material etc. to which zinc or zinc alloy material, and zinc plating are given. In particular, the zinc die cast material has an excellent effect.

  Finally, the film formation reaction mechanism of the present invention and the formed film will be outlined. A particularly preferable aluminum-containing material will be described as an example. The chemical conversion treatment liquid of the present invention is an acidic aqueous solution. Since aluminum and aluminum alloys are amphoteric metals, an aluminum etching (dissolution) reaction occurs when they are brought into contact with an acidic solution. In this etching reaction, aluminum changes from metal to ions, and electrons are generated. Hydrogen ions are received by these electrons and become hydrogen, and the decrease of hydrogen ions and the accompanying increase in pH occur near the material interface. The eluted aluminum is considered to react with hydrogen fluoride present in the chemical conversion liquid of the present invention to become aluminum fluoride. The zirconium compound and / or titanium compound, which is an essential component of the present invention, exists in the form of complex fluoride within the scope of the present invention. The equilibrium reaction of this complex fluoride changes due to dissociation and the like, and as a result, zirconium and / or titanium oxide (including hydroxide and hydrate) is deposited on the surface of the film. This oxide becomes the main component of the film, and the film is formed in a form incorporating a trivalent chromium compound (presumed to be chromium fluoride in the chemical conversion solution of the present invention) coexisting in the film. Therefore, the coating is composed of zirconium oxide, titanium oxide, or a composite oxide mixed with a trivalent chromium compound. In particular, it is considered that the trivalent chromium compound limited in the present invention has a great effect on imparting corrosion resistance.

  Examples of the chemical conversion treatment solution for metal and its surface treatment method according to the present invention will be described below with reference to examples and comparative examples, and the novelty and usefulness thereof will be described.

The following materials and test methods were used. The composition of the chemical conversion treatment solution and the treatment method are described in the examples.
<Metal material>
(1) Aluminum die-cast material (JIS-ADC12)
An aluminum die cast panel (manufactured by Partec Co., Ltd.) was used.
(2) Zinc die-cast material (JIS-ZDC2): used only in Examples 9 and 10 and Comparative Example 9 A zinc die-cast panel (manufactured by Partec Co., Ltd.) was used.
<Purification>
The sample metal material was immersed in a 2% aqueous solution of an alkaline degreasing agent (registered trademark Fine Cleaner 315 manufactured by Nippon Parkerizing Co., Ltd.) at 60 ° C. for 2 minutes, and then the surface was rinsed and cleaned with running tap water. .
<Deoxydizing>
The test metal material was immersed in a 2% aqueous solution of a treating agent (registered trademark Deoxy Diizer 7 manufactured by Nippon Parkerizing Co., Ltd.) at 40 ° C. for 1 minute, and then the surface was rinsed and cleaned with running tap water. Only Example 7 was performed.
<Measurement of adhesion amount>
The amount of chromium and zirconium and / or titanium deposited by the chemical conversion treatment was quantified using a fluorescent X-ray analyzer (system 3270E manufactured by Rigaku Corporation).
<Chemical conversion coating thickness>
The test sample was subjected to sputtering using a surface analyzer (ESCA-850M manufactured by Shimadzu Corporation), and the commercially available thickness was calculated from the time required for completion of the sputtering.
<Corrosion resistance evaluation>
The test sample was subjected to a salt spray test (JIS-Z2371), and the white rust generation area after 96 hours was measured and evaluated. In general, the white rust generation area ratio is preferably 10% or less, and 5% or less is a very good level.
<Coating adhesion>
A solvent-based paint (melamine alkyd system) was applied to a thickness of 30 μm on the surface of the test sample, and then a grid was cut. After immersing in boiling water for 1 hour, the water was wiped and the tape was peeled off. The state of the grid after peeling was observed. The number of squares was 100, and the number that did not peel was measured. Therefore, 100 is the best and 0 is the worst.
<Sludge generation test>
As for the above-mentioned ones that gave good results in the corrosion resistance evaluation, a sludge generation test was carried out for the purpose of evaluating the operability of industrialization. 1 liter of a chemical conversion treatment solution was prepared, and using this treatment solution, the area of 10 m ² of the test metal material was continuously treated. Each component was replenished so as to keep the initial value for fluctuations in the concentration of each component due to liquid loss (carrying out) due to coating and treatment. And the liquid after a process was left still at 40 degreeC for 48 hours, and the state of the subsequent liquid was observed. Sediment (sludge) and liquid state (turbidity, etc.) were observed. It is preferable that no sludge is generated.

Example 1
The following chemical conversion treatment liquid 1 was prepared, and the chemical conversion treatment 1 was performed on the cleaned metal material (1).
<Surface treatment liquid 1>
(A): Chromium fluoride: 10 mmol / liter (B): Fluorotitanic acid: 5 mmol / liter (C): Magnesium nitrate: 10 mmol / liter (D): Aluminum nitrate: 0.4 mmol / liter (E): Fluorination Hydrogen and fluorotitanic acid added in (B) (total fluorine): 65 mmol / liter (F): None
pH: 4.0 Adjusted with ammonia water <Treatment method 1>
Processing temperature: 40 ° C
Treatment time: 120 seconds Contact method: Immersion Process: Washed with tap water after treatment (room temperature, 30 seconds) + deionized water wash (room temperature, 30 seconds)
Dry in an electric oven (100 ° C-3 minutes)

Example 2
A chemical conversion treatment liquid 2 was prepared, and the chemical conversion treatment 2 was applied to the cleaned metal material (1).
<Surface treatment liquid 2>
(A): Chromium nitrate: 5 mmol / l (B): Fluorotitanic acid: 2 mmol / l Fluorozirconic acid: 3 mmol / l (C): Magnesium nitrate: 5 mmol / l (D): Aluminum nitrate: 0.4 mmol / l (E): Hydrogen fluoride and fluoro acid added in (B) (total fluorine): 60 mmol / liter (F): None
pH: 3.0 Adjusted with ammonia water <Treatment method 2>
Processing temperature: 60 ° C
Treatment time: 60 seconds Contact method: spray treatment Process: Washed with tap water after treatment (room temperature, 30 seconds) + deionized water wash (room temperature, 30 seconds)
Dry in an electric oven (100 ° C-3 minutes)

Example 3
The following chemical conversion treatment liquid 3 was prepared, and chemical conversion treatment was performed on the cleaned metal material (1) by the treatment method 3.
<Surface treatment liquid 3>
(A): Chromium nitrate: 1 mmol / liter (B): Ammonium zirconium nitrate: 1 mmol / liter (C): Magnesium nitrate: 1 mmol / liter (D): Aluminum nitrate: 1 mmol / liter (E): Hydrogen fluoride (total Fluorine): 15 mmol / liter (F): Hydrogen peroxide: 1 mmol / liter
pH: 4.0 Adjusted with ammonium bicarbonate <Treatment method 3>
Processing temperature: 60 ° C
Treatment time: 480 seconds Contact method: Immersion Process: Washed with tap water after treatment (room temperature, 30 seconds) + deionized water wash (room temperature, 30 seconds)
Dry in an electric oven (100 ° C-3 minutes)

Example 4
The following chemical conversion treatment liquid 4 was prepared, and the chemical conversion treatment 4 was applied to the cleaned metal material (1).
<Surface treatment liquid 4>
(A): Chromium nitrate: 5 mmol / l (B): Fluorotitanic acid: 2 mmol / l Fluorozirconic acid: 3 mmol / l (C): Calcium nitrate: 5 mmol / l Magnesium sulfate: 1 mmol / l (D): Fluoride Aluminum: 10 mmol / liter (E): Hydrogen fluoride and fluoro acid added in (B) (total fluorine): 80 mmol / liter (F): None
pH: 3.5 Adjusted with ammonia water <Treatment method 4>
Processing temperature: 50 ° C
Treatment time: 180 seconds Contact method: Immersion treatment Process: Washed with running water after treatment (room temperature, 30 seconds) + deionized water wash (room temperature, 30 seconds)
Dry in an electric oven (100 ° C-3 minutes)

Example 5
The following chemical conversion treatment solution 5 was prepared, and the chemical conversion treatment 5 was applied to the purified metal material (1).
<Surface treatment liquid 5>
(A): Chromium fluoride: 15 mmol / liter (B): Ammonium fluorozirconate: 8 mol / liter (C): Magnesium fluoride: 0.2 mmol / liter (D): Aluminum fluoride: 0.2 mmol / liter ( E): Fluoride added in (A) and (B) (total fluorine): 93 mmol / liter (F): None
pH: 2.6 Adjustment with nitric acid <Treatment method 5>
Processing temperature: 50 ° C
Treatment time: 300 seconds Contact method: Immersion treatment Process: Washed with tap water after treatment (room temperature, 30 seconds) + deionized water wash (room temperature, 30 seconds)
Dry in an electric oven (100 ° C-3 minutes)

Example 6
The following chemical conversion treatment liquid 6 was prepared, and the chemical conversion treatment 6 was performed on the purified metal material (1) by the following treatment method 6.
<Surface treatment liquid 6>
(A): Chromium nitrate: 15 mmol / l (B): Fluorotitanic acid: 1 mmol / l Fluorozirconic acid: 1 mmol / l (C): Magnesium nitrate: 20 mmol / l (D): Aluminum nitrate: 0.4 mmol / l (E): Hydrogen fluoride and fluoro acid added in (B) (total fluorine): 45 mmol / liter (F): None
pH: 3.5 Adjusted with ammonia water <Treatment method 6>
Processing temperature: 35 ° C
Treatment time: 480 seconds Contact method: Immersion treatment Process: Washed with tap water after treatment (room temperature, 30 seconds) + deionized water wash (room temperature, 30 seconds)
Dry in an electric oven (100 ° C-3 minutes)

Example 7
The following chemical conversion treatment liquid 7 was prepared, and the chemical conversion treatment was performed on the purified metal material (1) by the following treatment method 7.
<Surface treatment liquid 7>
(A): Chromium nitrate: 15 mmol / l (B): Fluorotitanic acid: 1 mmol / l Fluorozirconic acid: 1 mmol / l (C): Magnesium nitrate: 10 mmol / l Cerium nitrate: 1 mmol / l (D): Aluminum nitrate : 0.4 mmol / liter (E): Hydrogen fluoride and fluoro acid added in (B) (total fluorine): 45 mmol / liter (F): None
pH: 3.5 Adjusted with ammonia water <Treatment method 7>
Processing temperature: 45 ° C
Treatment time: 240 seconds Contact method: Immersion treatment Process: Washed with tap water after treatment (room temperature, 30 seconds) + deionized water wash (room temperature, 30 seconds)
Dry in an electric oven (100 ° C-3 minutes)

Example 8
The deoxydizing was performed on the cleaned metal material (1), and a chemical conversion treatment was performed in the same manner as in Example 7.

Example 9
Using the cleaned metal material (2) (zinc die-cast material), a chemical conversion treatment was performed in the same manner as in Example 1.

Example 10
Using the cleaned metal material (2) (zinc die-cast material), a chemical conversion treatment was performed in the same manner as in Example 7.

Comparative Example 1
The following chemical conversion treatment solution 7 was prepared, and the purified metal material (1) was subjected to chemical conversion treatment 7.
<Surface treatment liquid 7>
(A): Chromium nitrate: 15 mmol / liter (B): Fluorotitanic acid: 1 mmol / liter (C): Magnesium nitrate: 20 mmol / liter (D): Aluminum nitrate: 0.4 mmol / liter (E): (B) Fluoric acid added in (total fluorine): 6 mmol / liter (F): None
pH: 3.5 Adjusted with ammonia water <Treatment method 7>
Processing temperature: 30 ° C
Treatment time: 30 seconds Contact method: Immersion treatment Process: Washed with tap water after treatment (room temperature, 30 seconds) + deionized water wash (room temperature, 30 seconds)
Dry in an electric oven (100 ° C-3 minutes)

Comparative Example 2
The following chemical conversion treatment liquid 8 was prepared, and the purified metal material (1) was subjected to chemical conversion treatment by treatment method 8.
<Surface treatment liquid 8>
(A): None (B): Fluorotitanic acid: 1 mmol / liter (C): None (D): Aluminum nitrate: 0.4 mmol / liter (E): Fluoroacid added in (B) (total fluorine): 6 mmol / liter (F): None
pH: 2.3 Adjustment with nitric acid <Treatment method 8>
Processing temperature: 40 ° C
Treatment time: 30 seconds Contact method: Immersion treatment Process: Washed with tap water after treatment (room temperature, 30 seconds) + deionized water wash (room temperature, 30 seconds)
Dry in an electric oven (100 ° C-3 minutes)

Comparative Example 3
A commercially available non-chromate chemical conversion agent (trademark: 2% aqueous solution of allodin 404 (corresponding to Japanese Patent Laid-Open No. 52-131937) was used, and the cleaned metal material (1) was sprayed at 40 ° C. for 30 seconds. In the same manner as in the treatment method 1, washing with water, washing with deionized water, and drying were performed.

Comparative Example 4
An aqueous treatment liquid 8 (corresponding to Japanese Patent Application Laid-Open No. 2004-232047) containing 2 g / liter of iron hexacyanoate, 1 g / liter of fluorotitanic acid, and 1 g / liter of cobalt nitrate was made as a trial, and the purified metal material (1) Was dipped at 40 ° C. for 60 seconds. Next, in the same manner as in the treatment method 1, washing with water, washing with deionized water, and drying were performed.

Comparative Example 5
(1) titanium sulfate 1 mmol / liter, (2) hydrofluoric acid in an amount equivalent to 6 times the amount of titanium sulfate, (3) calcium nitrate 0.2 mmol / liter, (4) aluminum nitrate 0.2 mmol / liter A surface treatment liquid (corresponding to WO03 /: 074761 A1) containing 1 liter and (generating nitrate ions) was prototyped, and the cleaned metal material (1) was immersed at 40 ° C. for 60 seconds. Subsequently, it was washed with water, deionized water and dried in the same manner as in the treatment method 1.

Comparative Example 6
An aqueous surface treatment solution (corresponding to Japanese Patent No. 3333611) containing 10 mmol / liter of phosphoric acid, 10 mmol / liter of chromium phosphate, and 1 mmol / liter of fluorozirconic acid was produced as a prototype, and the purified metal material (1) was obtained at 40 ° C. For 60 seconds. Next, in the same manner as in the treatment method 1, washing with water, washing with deionized water, and drying were performed.

Comparative Example 7
A surface treatment solution (corresponding to JP 2000-332575 A) containing 10 g / liter of cerium nitrate, 100 ppm of chromium nitrate, and 100 ppm of hydrofluoric acid and having a pH adjusted to 2 with nitric acid at 50 ° C. The treated metal material (1) was immersed for 60 seconds at 40 ° C. for 2 minutes. Next, in the same manner as in the treatment method 1, washing with water, washing with deionized water, and drying were performed.

Comparative Example 8
The cleaned metal material (1) was subjected to immersion treatment at 40 ° C. for 20 seconds using a 5% aqueous solution (containing hexavalent chromium) of a chromate conversion agent (trademark: Alchrome 713 building bath). Next, in the same manner as in the treatment method 1, washing with water, washing with deionized water, and drying were performed.

Comparative Example 9
The following treatment liquid (according to Japanese Patent No. 35597542) was prepared. That is, 100 g / liter of CrCl ₃ .6H ₂ O (trivalent chromium salt), 100 g / liter of NaNO ₃ , 15.75 g / liter of NaF, and 26.5 g / liter of citric acid.1H ₂ O. The dissolved aqueous solution was adjusted to pH 2.5 with sodium hydroxide solution. The cleaned metal material (2) was treated in a boiling state for 30 seconds, then washed with water, washed with deionized water and dried.

  Table 1 shows the test results of Examples and Comparative Examples. In existing inventions, most of them have been found to have insufficient corrosion resistance. In Comparative Examples 6 and 9 having comparatively good corrosion resistance, sediment was generated when the sludge generation test was carried out, and there was a problem in operability (productivity) when industrialized. On the other hand, it was confirmed that the chemical conversion treatment liquid and method according to the present invention can provide excellent corrosion resistance, and also have excellent paint adhesion and excellent operability.

  The metal material chemical conversion treatment liquid and chemical conversion treatment method of the present invention have excellent corrosion resistance, paint adhesion, and sludge generation prevention without using a hexavalent chromium compound for the metal material. Is highly available.

Claims (13)

From component (A) comprising at least one water-soluble trivalent chromium compound, component (B) comprising at least one selected from water-soluble titanium compounds and water-soluble zirconium compounds, and at least one water-soluble nitrate compound In the aqueous treatment liquid containing the component (C) and the component (D) comprising at least one water-soluble aluminum compound, the component (E) comprising at least one fluorine compound in the treatment liquid A treatment liquid further containing
The water-soluble trivalent chromium compound-containing component (A) has a metal chromium equivalent content (CA) of 0.1 to 20 mmol / liter, and the water-soluble titanium compound and / or water-soluble zirconium compound-containing component (B) The total content (CB) in terms of metal titanium and metal zirconium is 0.1 to 10 mmol / liter, and the cation equivalent content (CC) of the water-soluble nitrate compound-containing component (C) is 0.2 to 40 mmol. / Liter, the content (CD) of the water-soluble aluminum compound (D) as aluminum is 0.2 to 40 mmol / liter, and the fluorine equivalent content (CE) of the fluorine compound-containing component (E) is as follows: Formula:
(CA × 2 + CB × 4 + CD × 2) ≦ CE ≦ (CA × 4 + CB × 7 + CD × 4)
[However, in the above formula, CA, CB, CD and CE are as defined above]
Is intended to satisfy, and metal material for chemical conversion treatment solution, wherein the pH of the processing liquid is controlled in the range from 2.3 5.0.   The chemical conversion treatment liquid for a metal material according to claim 1, wherein the surface treatment liquid further contains an oxidizing agent (F).   The chemical conversion liquid for metal materials according to claim 1 or 2, wherein the water-soluble trivalent chromium compound-containing component (A) contains at least one selected from chromium nitrate, chromium sulfate, and chromium fluoride.   The component (B) comprising the water-soluble titanium compound and / or water-soluble zirconium compound is titanium sulfate, titanium oxysulfate, titanium ammonium sulfate, titanium nitrate, titanium oxynitrate, titanium ammonium nitrate, titanium sulfate, titanium oxysulfate, sulfuric acid Titanium ammonium, titanium nitrate, titanium oxynitrate, ammonium ammonium nitrate, fluorotitanic acid, fluorotitanium complex, zirconium sulfate, zirconium oxysulfate, zirconium ammonium sulfate, zirconium nitrate, zirconium oxynitrate, ammonium zirconium nitrate, zirconium sulfate, zirconium oxysulfate , Ammonium zirconium sulfate, zirconium nitrate, zirconium oxynitrate, ammonium zirconium nitrate, fluorozirconic acid, fluorozirconium Salt, titanium lactate, titanium acetylacetonate, titanium triethanolaminate, titanium octyl glycolate, tetraisopropyl titanate, tetranormal butyl titanate, zirconyl acetate, zirconyl lactate, zirconium tetraacetylacetonate, zirconium tryptoxyacetylacetonate, tetra The chemical conversion liquid for metal materials of Claim 1 or 2 containing at least 1 sort (s) chosen from normal butoxyzirconium and tetranormal propoxyzirconium.   The chemical conversion liquid for metal materials according to claim 1 or 2, wherein the water-soluble nitrate compound-containing component (C) contains at least one selected from magnesium nitrate, calcium nitrate, strontium nitrate, manganese nitrate, and cerium nitrate.   The chemical conversion liquid for metal materials of Claim 1 or 2 in which the said water-soluble aluminum compound containing component (D) contains at least 1 sort (s) chosen from aluminum nitrate, aluminum sulfate, and aluminum fluoride.   The fluorine compound-containing component (E) is at least selected from hydrofluoric acid, ammonium fluoride, chromium fluoride, fluorotitanic acid, fluorotitanium complex, fluorozirconic acid, fluorozirconium complex, magnesium fluoride, and aluminum fluoride. The chemical conversion liquid for metal materials of Claim 1 or 2 containing 1 type.   The chemical conversion treatment for a metal material according to claim 2, wherein the oxidizing agent (F) includes at least one selected from a peroxo acid compound and a nitrous acid compound, and the content thereof is 0.1 to 15 mmol / liter. liquid.   The chemical conversion liquid for metal materials according to any one of claims 1 to 8, wherein the metal material is selected from aluminum and aluminum alloy materials, zinc and zinc alloy materials, and galvanized metal materials. From component (A) comprising at least one water-soluble trivalent chromium compound, component (B) comprising at least one selected from water-soluble titanium compounds and water-soluble zirconium compounds, and at least one water-soluble nitrate compound In the aqueous treatment liquid containing the component (C) and the component (D) comprising at least one water-soluble aluminum compound, the component (E) comprising at least one fluorine compound is added to the treatment liquid. Furthermore , the chemical conversion treatment liquid for metal material contained is heated to a temperature of 30 to 70 ° C. and brought into contact with a clean metal material surface for 1 to 600 seconds . The metal chromium equivalent content (CA) of the trivalent chromium compound-containing component (A) is 0.1 to 20 mmol / liter, and the water-soluble titanium compound and / or water-soluble zirconium The total content (CB) in terms of metal titanium and metal zirconium in the onium compound-containing component (B) is 0.1 to 10 mmol / liter, and the cation equivalent content (CC) in the water-soluble nitrate compound-containing component (C) Is 0.2 to 40 mmol / liter, the content (CD) of the water-soluble aluminum compound (D) as aluminum is 0.2 to 40 mmol / liter, and the fluorine compound-containing component (E) is fluorine. Converted content (CE) is the following formula:
(CA × 2 + CB × 4 + CD × 2) ≦ CE ≦ (CA × 4 + CB × 7 + CD × 4)
[However, in the above formula, CA, CB, CD and CE are as defined above]
And the pH of the chemical conversion treatment liquid is controlled to be within the range of 2.3 to 5.0, thereby preventing generation of sludge in the chemical conversion liquid, and the metal material Then, a chemical conversion film having excellent corrosion resistance is formed on the surface of the metal material , and then the metal material surface is washed with water and dried, and 0.02 to 1 mmol / m ² of chromium and 0.02 to 0.02 on the metal material surface. A chemical conversion treatment method for a metal material surface, comprising forming a chemical conversion film containing 1 mmol / m ² of titanium and / or zirconium and having a thickness of 1 to 100 nm.   The chemical conversion treatment method of the metal material surface of Claim 10 which performs deionization washing | cleaning to the said metal material surface washed with water between the said water washing and drying.   11. The metal according to claim 10, wherein the surface of the clean metal material is one in which oxide is removed by subjecting the surface of the metal material to deoxydizing treatment with an aqueous treatment liquid having an acid or a redox agent. A chemical conversion treatment method for the material surface.   The chemical conversion treatment method for a metal material surface according to any one of claims 10 to 12, wherein the clean metal material is selected from aluminum and an aluminum alloy material, zinc and a zinc alloy material, and a galvanized metal material.