JP2000199077A - Composition for metallic surface treatment, surface treating solution and surface treating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composition for metallic surface treatment of the nonchromate type capable of imparting excellent corrosion resistance and adhesion for a coating film to the metallic surfaces of alminum (alloys), magnesium (alloys), zinc (alloys) or the like. SOLUTION: This composition contains at least one kind of metallic acetylacetonates selected from the group composed of Al(C5H7O2)3, V(C5H7O2)3, VO(C5H7O2)2, Zn(C5H7O2)2 and Zr(C5H7O2)4 and at leawst one kind of compd. selected from a water soluble inorganic titanium compd. and a water soluble inorganic zirconium compd. by the weight ratio of (1:5,000) to (5,000:1).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a novel metal surface treatment for imparting excellent corrosion resistance and coating adhesion to various metals such as aluminum, aluminum alloys, magnesium, magnesium alloys and galvanized steel sheets. The present invention relates to a composition for use, a surface treatment liquid, and a surface treatment method.

[0002]

2. Description of the Related Art In general, surface treatment solutions for aluminum or aluminum alloy materials can be broadly classified into chromate type and non-chromate type. Representative examples of the chromate-type treatment liquid include a chromate chromate conversion treatment liquid and a phosphoric acid chromate conversion treatment liquid.

First, a chromate chromate conversion treatment solution will be described. Chromate chromate conversion solution is 195
It was put into practical use around 0 years, and is still widely used for surface treatment of automotive heat exchangers, aluminum wheels, building materials, and aircraft materials. This chromate chromate conversion treatment solution contains chromic acid and fluoride as a reaction accelerator as main components, and forms a chemical conversion film containing a small amount of hexavalent chromium on the surface of the metal material.

[0004] A phosphoric acid chromate conversion treatment solution according to the invention disclosed in US Pat. No. 2,438,877, which contains chromic acid, phosphoric acid and hydrofluoric acid as main components, and is formed on the surface of a metal material. A chemical conversion film composed mainly of hydrated chromium phosphate is formed. Since the conversion coating does not contain hexavalent chromium, the body of the beverage can
It is widely used at present for coating undercoating of materials and lids. Although the chemical conversion film formed by such a chromate-type surface treatment solution has excellent corrosion resistance and coating film adhesion, it contains harmful hexavalent chromium in the treatment solution. It has been desired to use a processing solution containing no hexavalent chromium at all.

[0005] A typical invention of a non-chromate type surface treatment solution containing no chromium is disclosed in JP-A-52-1.
Japanese Patent Application Laid-Open No. 31937 discloses a treatment liquid. This surface treatment solution is an acidic aqueous coating solution containing zirconium or titanium or a mixture thereof, phosphate and fluoride, and having a pH of about 1.5 to 4.0. When the surface of a metal material is treated with this surface treatment liquid, a chemical conversion film containing zirconium or titanium oxide as a main component is formed on the metal surface. This non-chromate type surface treatment liquid has the advantage that it does not contain hexavalent chromium, and is currently widely used for the surface treatment of aluminum DI cans. There is a disadvantage that it is inferior to the film.

[0006] Examples of the non-chromate type processing solution include those disclosed in the following patent publications. For example, the treatment method disclosed in JP-A-57-41376 discloses a method in which one or two or more of a titanium salt or a zirconium salt and one or more of an imidazole derivative are formed on the surface of aluminum, magnesium or an alloy thereof. Surface treatment using an aqueous solution containing an oxidizing agent such as nitric acid, hydrogen peroxide, potassium permanganate and the like. The corrosion resistance of the film formed by this treatment solution was sufficient 15 years ago. However, it is not at all satisfactory at present. Also,
JP-A-56-13678 discloses a chemical conversion treatment solution 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. Have been.
However, a chemical conversion film formed using this treatment solution cannot be expected to have a corrosion resistance equal to or higher than that of a chromate film when a long-term corrosion resistance test is performed.

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. For these reasons, in non-chromate type surface treatment liquids, at present, almost no surface treatment liquids are used in surface treatment lines for aluminum alloy heat exchangers, aluminum-based metal coils and sheet materials, etc., which require particularly excellent corrosion resistance. It is not used.

Accordingly, at present, a surface for aluminum or aluminum alloy material which does not contain hexavalent chromium in the treatment liquid, has excellent wastewater treatment properties, and can form a chemical conversion film having excellent corrosion resistance and coating film adhesion. The processing solution has not been established.

Next, a surface treating solution and a surface treating method for magnesium or a magnesium alloy will be described.
Surface treatment methods for magnesium or magnesium alloy materials include JIS-H-8651 and MIL-M-3.
171 and the like have been put to practical use. Although the chemical conversion film formed by such a chromate-type surface treatment solution has excellent corrosion resistance and coating film adhesion, it contains very harmful hexavalent chromium in the treatment solution, so that it is environmentally friendly. From a problem, it is desired to use a processing solution containing no hexavalent chromium at all.

A typical invention of a non-chromate type surface treatment solution containing no chromium is disclosed in Japanese Patent Publication No. 3-69.
No. 94 discloses a method disclosed therein. In this treatment method, silicate treatment is performed after phosphate treatment, and silicone treatment is further performed on the silicate treatment. There is a problem that the level of coating film adhesion is low. Further, this processing method has disadvantages such as requiring a multi-stage processing step, a high processing temperature and a long processing time. As a surface treatment method using a phosphate, a method using a treatment solution such as a zinc phosphate-based, iron phosphate-based, calcium phosphate-based, or zirconium phosphate-based treatment solution is known. It is difficult to provide sufficient corrosion resistance. For example, JIS-H-8
The manganese phosphate treatment is indicated in 7 types of 651. However, since this treatment solution contains chromium, the treatment temperature is as high as 80 to 90 ° C, and the treatment time is as long as 30 to 60 minutes. Unsatisfactory for practical use.

The following publications are mentioned as non-chromate type technologies. JP-A-9-228062 discloses that at least one kind of an organic metal compound selected from a metal alkoxide, a metal acetylacetonate and a metal carboxylate, and an acid, an alkali, a salt thereof, or any one of a hydroxyl group, a carboxyl group, and an amino group Discloses a surface treatment method in which an aqueous solution containing at least one film-forming aid or film-forming stabilizer selected from organic compounds having the following formula is applied to a magnesium material at a temperature of 0 to 50 ° C. However, a chemical conversion film formed using this treatment solution cannot be expected to have a corrosion resistance equal to or higher than that of a chromate film when a long-term corrosion resistance test is performed.

As described above, when a non-chromate type surface treatment solution conventionally proposed for the magnesium or magnesium alloy is used, the formed chemical conversion film has high corrosion resistance, high processing temperature, long processing time, Problems remain in practical processing conditions such as high processing concentration and low corrosion resistance. For this reason, at present, non-chromate type surface treatment is applied to surface treatment lines of magnesium alloy automotive materials, aircraft materials, electronic equipment materials and communication equipment materials, etc., which require excellent corrosion resistance and coating film adhesion. The liquid is rarely used. Therefore, a surface treatment solution for magnesium or magnesium alloy material that does not contain hexavalent chromium in the treatment solution at present and has excellent workability and can form a chemical conversion film with excellent corrosion resistance and coating film adhesion has been established. It is not done.

Next, the surface treatment of the galvanized material will be described. As a treatment method for a zinc plating material, a chromate treatment or a zinc phosphate treatment is generally used. Although excellent film performance can be obtained by chromate treatment, harmful chromium is contained in the treatment liquid, which is a problem in work and disposal. In addition, in the zinc phosphate treatment, sufficient corrosion resistance may not be obtained.

As a technique of a non-chromate type of a galvanized material, there is a method proposed in the following gazette. Japanese Patent Application Laid-Open No. 1-104878 discloses Si, Ti, Z
An alcohol solution containing one or more of alkoxides or acetylacetonate salts of r, Al, W, Ce, Sn, and Y is applied to zinc, aluminum, or a zinc-aluminum alloy-plated steel sheet, and the temperature is 200 to 500 ° C.
A method for producing a surface-treated steel sheet, characterized by forming a metal oxide film contained in a solution on the surface of the steel sheet by heating the steel sheet. However, in this production method, flammable alcohol must be used, and a considerably high temperature is required at the time of film formation, and thus there is a problem in working environment and energy cost.

[0015] From the above, the surface treatment of the galvanized material does not contain harmful chromium in the treatment liquid, is excellent in workability, and is excellent in corrosion resistance and corrosion in the same manner as in the case of aluminum-based material and magnesium-based material. A surface treatment solution capable of forming a chemical conversion film having excellent coating film adhesion has not been established.

[0016]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and specifically, is capable of imparting excellent corrosion resistance and coating film adhesion to a metal surface. It is an object of the present invention to provide a composition for metal surface treatment, a surface treatment liquid, and a surface treatment method.

[0017]

Means for Solving the Problems The present inventors have intensively studied means for solving the above-mentioned problems of the prior art. As a result, a specific amount of _{Al (C 5 H 7 O 2} ) 3,
_{V (C 5 H 7 O 2} ) 3, VO (C 5 H 7 O 2) 2, Zn (C 5 H 7 O 2) 2
And at least one metal acetylacetonate selected from Zr (C ₅ H ₇ O ₂ ) ₄ and at least one compound selected from a water-soluble inorganic titanium compound and a water-soluble inorganic zirconium compound in a specific ratio. Treatment composition,
Also, the present inventors have newly found that a chemical conversion film having excellent corrosion resistance and coating film adhesion can be formed on a metal surface by using a surface treatment solution using this composition, and have completed the present invention.

That is, the composition for metal surface treatment of the present invention comprises:
_{Al (C 5 H 7 O 2} ) 3, V (C 5 H 7 O 2) 3, VO (C 5 H
_At least one metal acetylacetonate selected from the group consisting of ₇ O ₂ ) ₂ , Zn (C ₅ H ₇ O ₂ ) ₂ and Zr (C ₅ H ₇ O ₂ ) ₄ , and a water-soluble inorganic titanium compound; At least one compound selected from water-soluble inorganic zirconium compounds is contained in a weight ratio of 1: 5000 to 5000: 1. Further, the surface treatment liquid of the present invention,
_{Al (C 5 H 7 O 2} ) 3, V (C 5 H 7 O 2) 3, VO (C 5 H
_At least one metal acetylacetonate selected from ₇ O ₂ ) ₂ , Zn (C ₅ H ₇ O ₂ ) ₂ and Zr (C ₅ H ₇ O ₂ ) ₄ in an amount of 0.01 to 50 g / L, 1. contains at least one compound selected from the group consisting of a water-soluble inorganic titanium compound and a water-soluble inorganic zirconium compound in an amount of 0.01 to 50 g / L;
It has a pH of 0 to 7.0. Furthermore, the surface treatment method of the present invention is characterized in that the metal surface treatment solution is brought into contact with aluminum or an alloy thereof, magnesium or an alloy thereof, or zinc or an alloy thereof so as to have a coating weight of 5 to 2000 mg / m ^2.
A method for treating a surface of a metal, comprising forming an organic-inorganic composite chemical conversion film. Next, the configuration of the present invention will be described in detail.

The surface treatment composition of the present invention comprises Al (C_FiveH₇
O_Two)_Three, V (C_FiveH₇O_Two)_Three, VO (C_FiveH ₇O_Two)_Two, Zn (C_Five
H₇O_Two)_TwoAnd Zr (C_FiveH₇O_Two)_FourSelected from the group consisting of
At least one metal acetylacetonate, and water-soluble
Inorganic titanium compounds and water-soluble inorganic zirconium compounds?
At least one compound selected from the group consisting of
Have In the present invention, a specific metal
Inorganic compound of tilacetonate and titanium, specific metal
There is an inorganic compound of cetyl acetonate and zirconium,
Or specific metal acetylacetonate, titanium and zircon
Metallic acetylacetonate, like inorganic compounds of
And titanium and / or zirconium inorganic compounds
It is most important to form an organic-inorganic composite film
As a result, the corrosion resistance of the formed chemical conversion coating is particularly improved.
It is thought to improve. Essential of the surface treatment composition of the present invention
As the metal acetylacetonate as a component, Al
(C_FiveH₇O_Two)_Three, V (C_FiveH₇O_Two)_Three, VO (C_FiveH₇O_Two)_Two, Z
n (C_FiveH₇O_Two)_TwoAnd Zr (C_FiveH₇O_Two)_FourSelected from the group consisting of
At least one of them.

The water-soluble inorganic titanium compound or water-soluble inorganic zirconium compound which is an essential component of the surface treatment composition of the present invention includes titanium or zirconium sulfate,
One or more selected from oxysulfates, nitrates, phosphates, chlorides, ammonium salts, fluorides and the like can be used, and the type is not particularly limited as long as it is a water-soluble inorganic compound. . These water-soluble inorganic titanium compounds and water-soluble inorganic zirconium compounds are deposited on the surface of the metal to be treated in the form of oxides, phosphates or fluorides of Ti and Zr, and simultaneously with the precipitated metal acetylacetonate. The skeleton portion of the organic-inorganic composite film formed by the above. And, due to the presence of Ti and Zr,
The barrier property (shielding power) of the coating against the corrosive environment is improved,
As a result, it is possible to form a film having better corrosion resistance and coating film adhesion than when metal acetylacetonate is used alone.

The mixing ratio of the metal acetylacetonate and the water-soluble inorganic compound must be 1: 5000 to 5000: 1. It is preferably from 1: 100 to 400: 1, more preferably from 1:50 to 100: 1, and still more preferably from 1:10 to 10: 1. This weight ratio is 1:
When it is less than 5000, the formed organic-inorganic composite film has poor corrosion resistance. Conversely, when the ratio exceeds 5000: 1, the organic-
It becomes difficult to form an inorganic composite film.

Next, the metal surface treatment liquid of the present invention basically uses the surface treatment composition and water. First,
The content of the metal acetylacetonate in the processing solution is 0.0
The range is preferably 1 to 50 g / L, more preferably 0.1 g / L.
It is in the range of 1 to 20 g / L. Even if the content of the metal acetylacetonate is less than 0.01 g / L, a chemical conversion film is formed, but it is not preferable because the corrosion resistance and the coating film adhesion are poor. Even if the amount exceeds 50 g / L, a good chemical conversion film is formed, but the effect is saturated and the cost of the treatment liquid increases, which is economically wasteful. The content of the water-soluble inorganic titanium compound and the water-soluble inorganic zirconium compound is 0.01 to
The range is preferably 50 g / L, more preferably 0.05 g / L.
-10 g / L. Even if the content is less than 0.01 g / L, a chemical conversion film is formed, but it is not preferable because the corrosion resistance is poor. Even if the amount exceeds 50 g / L, a good chemical conversion film is formed, but the effect is saturated, the cost is increased, and it is economically useless.

The pH of the surface treatment solution of the present invention is 2.0 to 2.0.
It must be adjusted to a range of 7.0. More preferably, the pH is in the range of 3.0 to 6.0. pH 2.0
If the amount is less than the above, it is not preferable because unevenness in appearance due to excessive etching on the surface of the metal material occurs and metal acetylacetonate hardly precipitates on the metal surface. Also, pH
Is more than 7.0, it is difficult to form a chemical conversion film having excellent corrosion resistance, or the metal ions contained in the processing solution tend to form a precipitate, which causes a problem in the stability of the solution. Is not preferred. When adjusting the pH of the surface treatment solution of the present invention to a range of 2.0 to 7.0, an acid such as nitric acid, sulfuric acid, phosphoric acid, hydrofluoric acid, hydrofluoric acid and the like, if necessary, and Alkali such as sodium hydroxide, sodium carbonate, potassium hydroxide and ammonium hydroxide can be used.

In the surface treatment of the present invention, metal ions such as aluminum, magnesium, and zinc are eluted from the metal material to be treated into the surface treatment solution, so that the stability of the treatment solution may be significantly reduced. In this case, in order to chelate these metal ions, an organic acid such as gluconic acid, heptogluconic acid, oxalic acid, tartaric acid, organic phosphonic acid, or ethylenediaminetetraacetic acid, or an alkali metal salt thereof is added to the treatment solution as a blocking agent. You may.

In the present invention, hydrogen peroxide, tungstic acid and salts thereof, molybdic acid and salts thereof, permanganic acid and salts thereof, and tert-butyl hydroperoxide are used to promote the formation of a chemical conversion film. ((CH
_{3) 3} CO-OH) may be used in combination oxidizing agent such as water-soluble organic peroxides such as.

The weight of the organic-inorganic composite chemical conversion film formed by the above method is preferably in the range of 5 to 2000 mg / m ² , more preferably in the range of 50 to 500 mg / m ² . If the coating weight is less than 5 mg / m ² , the corrosion resistance and coating adhesion may be insufficient, which is not preferred. Further, even if the film weight exceeds 2000 mg / m ² , the corrosion resistance is excellent, but the effect is saturated, the cost is increased, and it is economically wasteful. The film weight is 2000mg / m
^If it exceeds ² , the adhesion of the coating film tends to decrease, and the appearance of the coating becomes uneven, which is not preferable from these points.

With respect to the metal components of aluminum, vanadium, zinc, zirconium, and titanium, which are one of the constituent components of the chemical conversion film, their presence in the film, such as the bonding state, oxidation state, and polymerized state, is considered. Is not particularly limited.

Next, the surface treatment liquid of the present invention, aluminum or its alloy, magnesium or its alloy,
Alternatively, a chemical conversion film having excellent corrosion resistance and coating film adhesion can be formed by contact with zinc or an alloy thereof. Hereinafter, a method of surface-treating various metal materials will be described.

The surface treatment liquid of the present invention is preferably applied in the following steps. Surface cleaning: degreasing (acidic, neutral, alkaline, solvent-based cleaning agents may be used) Rinse surface Treatment with the treatment liquid of the present invention Rinse water Deionized water rinse Dry

The surface treating solution of the present invention is preferably brought into contact with the surface of the metal material at a temperature of 10 to 80 ° C. for a time of 1 to 600 seconds. If this contact temperature is 10
If the temperature is lower than 80 ° C., the reactivity between the treatment solution and the metal surface is insufficient, so that a good chemical conversion film is not formed. If the temperature exceeds 80 ° C., a chemical conversion film is formed, but the energy cost is increased. It is economically useless. Further, if the treatment time is less than 1 second, the reaction does not sufficiently proceed, and a chemical conversion film having excellent corrosion resistance is not formed. On the other hand, even if the time exceeds 600 seconds, no improvement in the corrosion resistance and coating film adhesion of the resulting chemical conversion film is observed. In the present invention, the contact method with the surface treatment liquid is:
Any of an immersion method and a spray method may be used.

The aluminum or aluminum alloy material to which the surface treatment composition and the surface treatment solution of the present invention are applied includes metals composed of pure aluminum and aluminum alloy, and the aluminum alloy is, for example, Al-Cu, A
1-Mn, Al-Si, Al-Mg, Al-Mg-S
i, alloys of various component systems such as Al-Zn-Mg, and metal materials (such as aluminum-plated steel sheets) plated with Al or Al alloy. In addition, magnesium or a magnesium alloy material includes metals composed of pure magnesium and a magnesium alloy, and the magnesium alloy includes various component systems such as Mg-Al-Zn, Mg-Zn and Mg-Al-Zn-Mn. Alloys. Further, zinc or a zinc alloy is a metal material particularly subjected to Zn plating, and is a hot-dip galvanized steel sheet, an alloyed hot-dip galvanized steel sheet, an Al-Zn alloy-coated steel sheet (trade names: Galfan, Galvalume), an electro-galvanized steel sheet And alloy electrogalvanized steel sheets. In addition,
The aluminum and aluminum alloy material, magnesium and magnesium alloy material, and zinc and zinc alloy material are not limited in shape and size, and include, for example, plate materials and various molded products. In addition, the surface of these materials only needs to have a predetermined metal in at least a part thereof. For example, rolling or plating, or further treatment such as shot blasting, surface roughening by acid or alkali, activation, etc. May be applied.

[0032]

EXAMPLES Examples and comparative examples will be described below in more detail to explain the effects of the surface treatment composition, surface treatment solution and surface treatment method of the present invention.

Examples 1 to 5 and Comparative Examples 1 to 4 [Specimens] As the surface treated aluminum alloy material,
An Al-Mn alloy plate (JIS 3004) was used (dimensions: 150 mm x 70 mm, plate thickness 0.2 mm). As the surface-treated magnesium alloy material, a magnesium alloy AZ91D die-cast plate specified in JIS H2222 was used (dimensions: 150 mm × 100 mm, plate thickness 1 mm). As the surface-treated galvanized material, an alloyed hot-dip galvanized steel sheet was used (dimensions: 150 mm × 70 mm, thickness: 0.1 mm).
8mm).

[Treatment conditions] Next step →→→→
Processing was performed in the order of → to produce a surface-treated plate. Degreasing (43 ° C, 2 minutes, dipping method) Commercially available alkaline degreasing agent (registered trademark: Fine Cleaner L4460A; 2% and Fine Cleaner L4460)
B: A 1.2% mixed aqueous solution (both manufactured by Nippon Parkerizing Co., Ltd.) was used. Rinse with water (normal temperature, 30 seconds, spray method) Surface treatment (immersion method) Surface treatment was performed using a surface treatment solution having the composition shown in FIG. 1 (Table 5) and FIG. 2 (Table 6) and treatment conditions. Tables 1 to 3 show substances used in the surface treatment liquids of Examples 1 to 5 and Comparative Examples 1 to 4. In addition, the weight of each substance shown in the column of the treatment liquid composition in Tables 2 and 3 is a value converted as a pure component. The surface treatment conditions of Comparative Examples 5 to 9 are shown below. Rinse with water (normal temperature, 30 seconds, spray method) Deionized water rinse (normal temperature, 30 seconds, spray method) Heat drying (80 ° C, 3 minutes, hot air oven)

[0035]

TABLE 1 Metal acetylacenate used in surface treatment solutions of Examples 1 to 5 and Comparative Examples 1 to 4

[0036]

Table 2 Water-soluble titanium compounds used in the surface treatment solutions of Examples 1 to 5 and Comparative Examples 1 to 4

[0037]

Table 3 Water-soluble zirconium compounds used in the surface treatment solutions of Examples 1 to 5 and Comparative Examples 1 to 4

[0038]

Table 4 pH adjusters used in the surface treatment solutions of Examples 1 to 5 and Comparative Examples 1 to 4

Comparative Example 1 is a comparative example in which only a metal acetylacetonate was used as a treatment liquid component to form a single film of the metal acetylacetonate. Comparative Example 2 is a comparative example in which only a water-soluble inorganic titanium compound was used as a treatment liquid component to form a single film of the inorganic titanium compound. Comparative Example 3 is a comparative example in which a treatment liquid composition comprising a water-soluble inorganic titanium compound and a water-soluble inorganic zirconium compound was used to form an inorganic composite film composed of titanium and zirconium without metal acetylacetonate. . Comparative Example 4 is a comparative example in which a film having an extremely small film weight was formed.

Comparative Example 5 A 2% aqueous solution of a commercially available zirconium phosphate-based surface treating agent (registered trademark: Alodine 4040, manufactured by Nippon Parkerizing Co., Ltd.) was used for the surface treatment. Then, the solution was sprayed at a temperature of 50 ° C. for a time of 60 seconds under the spraying conditions.
The coating was applied to an alloy plate to evaluate corrosion resistance and coating film adhesion.

COMPARATIVE EXAMPLE 6 A commercially available aqueous solution of a phosphoric acid chromate-based surface treating agent (registered trademark: Alchrome K702SL; 4% and Alchrome K702AC; 0.3% aqueous solution) was used for surface treatment. Manufactured by the company). Then, this liquid was applied to the Al alloy plate under the conditions of a spray method at a temperature of 50 ° C. for a time of 20 seconds, and the corrosion resistance and coating film adhesion were evaluated.

Comparative Example 7 For the surface treatment, a 7% aqueous solution of a commercially available chromate chromate-based surface treating agent (registered trademark: Alchrome 713M, manufactured by Nippon Parkerizing Co., Ltd.) was used. Then, this solution was applied to the Al alloy plate, Mg alloy plate and Zn-plated steel plate at a temperature of 40 ° C. for a time of 60 seconds and immersion method, and the corrosion resistance and coating film adhesion were evaluated.

Comparative Example 8 MIL mainly containing sodium dichromate for surface treatment
A processing solution based on -M-3171C (TYPE III) was used. The liquid was applied to the Mg alloy plate at a temperature of 95 ° C. for 30 minutes under the immersion method, and the corrosion resistance and coating film adhesion were evaluated.

COMPARATIVE EXAMPLE 9 After the above-described degreasing and washing with water, a 0.1% aqueous solution of a commercially available titanium-based surface conditioner (registered trademark: Preparen 4040, manufactured by Nippon Pacalizing Co., Ltd.) was used at a temperature of 25 ° C. for 30 hours. For 2 seconds under the conditions of the immersion method.
After washing with water under spraying conditions for 2 seconds, an aqueous solution of a commercially available zinc phosphate-based surface treating agent (registered trademark: Palbond L) was used for surface treatment.
A mixed aqueous solution of 3020-5%, an additive 4813-0.5%, an additive 4856-2%, and a neutralizing agent 4055-1% (all manufactured by Nippon Parkerizing Co., Ltd.) was used. Then, this solution was applied to the Zn-plated steel sheet at a temperature of 43 ° C. for a time of 120 seconds under the immersion method, and the corrosion resistance and coating film adhesion were evaluated.

[Evaluation method] (1) Film weight X-ray fluorescence analyzer or 5% by weight chromic acid aqueous solution, 9
The entire coating weight of the organic-inorganic composite coating was measured using a peeling method by immersion at 0 ° C. for 5 minutes. (2) Corrosion resistance The evaluation of corrosion resistance used the salt spray test based on JIS-Z-2371. The state of corrosion of the surface-treated plate after the salt spray test was visually evaluated. The evaluation criteria for the salt spray time and the corrosion resistance for each test material subjected to the surface treatment are as follows. Spraying time Al alloy plate 480 hours Mg alloy plate 24 hours Zn-plated steel plate 120 hours Evaluation criteria ：: Corrosion area rate less than 10% ：: Corrosion area rate 10 % Or more and less than 30% Δ: Corrosion area rate 30% or more and less than 50% ×: Corrosion area rate 50% or more (3) Coating film adhesion Surface treatment was performed under the conditions of Examples 1 to 5 and Comparative Examples 1 to 9. An epoxy resin paint (manufactured by Kansai Paint Co., Ltd.) is applied to the surface of the Al alloy plate, Mg alloy plate or Zn-plated steel plate so as to have a dry film thickness of 10 μm.
Baking for minutes. Next, a grid of 100 squares of 2 mm width was put in the center of the coated plate with a cutter and immersed in deionized boiling water for 60 minutes. Then, after the coated plate was air-dried, a cellophane tape peeling test was performed, and the adhesion of the coating film was evaluated based on the number of crosscuts that did not peel off at this time. In addition,
The larger the number of the residuals, the better the adhesion of the coating film. If the number of the residuals is 98 or more, the performance is practically sufficient.

The evaluation results are shown in FIG. 1 (Table 5) and FIG. 2 (Table 6).
Shown in From Tables 5 and 6, the conversion coating formed by the surface treatment solution of the present invention has the same corrosion resistance and coating adhesion as the conventional chromate coating, and the metal acetylacetonate and Ti / Zr of the equivalent coating weight. It is understood that excellent corrosion resistance can be realized by forming an organic-inorganic composite film in which is present.

[0047]

As is clear from the above description, by applying the surface treatment composition and the surface treatment solution according to the present invention to an aluminum-containing material, a magnesium-containing material, or a galvanized material, excellent corrosion resistance and excellent corrosion resistance can be obtained. It became possible to form a chemical conversion film having coating film adhesion. Therefore, the surface treatment liquid of the present invention is extremely useful in practical use.

[Brief description of the drawings]

FIG. 1 is a chart (Table 5) showing compositions, conditions and evaluation test results of surface treatment solutions in Examples 1 to 5.

FIG. 2 is a table (Table 6) showing compositions, conditions, and evaluation test results of surface treatment solutions in Comparative Examples 1 to 9.

Claims (3)

[Claims] 1. An Al (C ₅ H ₇ O ₂ ) ₃ , V (C ₅ H ₇ O ₂ ) ₃ , V
O (C ₅ H ₇ O ₂ ) ₂ , Zn (C ₅ H ₇ O ₂ ) ₂ and Zr (C ₅ H
₇ O ₂ ) ₄ and at least one metal acetylacetonate selected from the group consisting of a water-soluble inorganic titanium compound and a water-soluble inorganic zirconium compound.
A composition for treating a metal surface, comprising a kind of a compound in a weight ratio of 1: 5000 to 5000: 1. 2. Al (C ₅ H ₇ O ₂ ) ₃ , V (C ₅ H ₇ O ₂ ) ₃ , V
O (C ₅ H ₇ O ₂ ) ₂ , Zn (C ₅ H ₇ O ₂ ) ₂ and Zr (C ₅ H
_At least one metal acetylacetonate selected from the group consisting of ₇ O ₂ ) ₄ and 0.01 to 50 g / L, and at least one compound selected from a water-soluble inorganic titanium compound and a water-soluble inorganic zirconium compound. 0.01-50g
/ L content, and having a pH of 2.0 to 7.0. 3. An organic-inorganic material having a coating weight of 5 to 2000 mg / m ₂ by contacting the metal surface treatment liquid according to claim 2 with aluminum or an alloy thereof, magnesium or an alloy thereof, or zinc or an alloy thereof. A method for treating a metal surface, comprising forming a composite chemical conversion film.