JP2003313676A - Chromium-free surface treatment agent for metal, chromium-free surface treatment method for metal, and aluminum or aluminum alloy sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a chromium-free surface treatment agent for metals, superior in stability while imparting adequate adhesiveness to a laminated metallic material. <P>SOLUTION: The chromium-free surface treatment agent for metals comprises a water-soluble zirconium compound and/or a water-soluble titanium compound (1), and tannin (2), wherein a content of the above water-soluble zirconium compound and/or the water-soluble titanium compound (1) is 20-800 ppm by mass base in zirconium and/or titanium terms, and the content of the above tannin (2) is 100-4,000 ppm by mass base; has a pH of 1.4-4.0; and is used for manufacturing a thermoplastic polyester resin coated metal sheet. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a non-chrome metal surface treatment agent, a non-chrome metal surface treatment method, and an aluminum or aluminum alloy plate.

[Prior art]

[0002] In recent years, as a method of coating a metal material, a polyester-based coating material is used from the viewpoints of improving the protective function of the coating material, improving the aesthetic appearance, and contributing to environmental protection without the emission of an organic solvent in the coating process. Resin film heat fusion,
The application of the laminating method by melt extrusion coating of polyester resin is expanding.

As an example of a thin plate material which is a material of a laminated metal material, a metal plate such as aluminum or aluminum alloy can be cited. Such a metal plate is usually preliminarily subjected to an alkali cleaning treatment and then a surface treatment for providing adhesion.

Conventionally, a phosphoric acid chromate-based treating agent has been mainly used as a surface treating agent for laminated metal materials, but in recent years, there has been an increasing demand for adhesion of the coated film to a substrate. From the perspective of environmental protection
There is a need for a surface treatment agent that does not contain chromium and that can impart high adhesion.

JP-A-52-95546 discloses an aqueous solution containing, as main components, one or more selected from the group of tannin, tannic acid and decomposition products of tannic acid, and titanium salts or zirconium salts. A method for surface treatment of aluminum, magnesium, and alloys thereof, which is surface-treated in accordance with US Pat. This is a method carried out for the purpose of applying to aluminum, magnesium and alloys thereof for construction, automobiles, electric appliance materials, and has not been examined for laminated metal materials.

As the reactive chromium-free surface treatment agent,
For example, zirconium fluoride-based and zirconium phosphate-based treatment agents have been put to practical use for beverage can bodies and the like. However, such a conventional chrome-free surface treatment agent can give high adhesion to the paint used for the body of a beverage can, but the adhesion required for a laminated metal material. It wasn't something that could satisfy her.

[0007]

SUMMARY OF THE INVENTION In view of the above situation, it is an object of the present invention to provide a non-chromium metal surface treatment agent which provides a laminated metal material with sufficient adhesion and is excellent in stability. Is.

[0008]

The present invention is a non-chromium metal surface treating agent comprising a water-soluble zirconium compound and / or a water-soluble titanium compound (1) and tannin (2), wherein the water-soluble zirconium compound is used. And / or the content of the water-soluble titanium compound (1) is 20 to 800 on a mass basis as the amount of zirconium and / or titanium.
ppm, the content of the tannin (2) is 100 to 4000 ppm on a mass basis, the non-chromium metal surface treatment agent has a pH of 1.4 to 4.0, a thermoplastic polyester resin coated metal It is a non-chromium metal surface treatment agent characterized by being used for manufacturing a plate.

The above non-chrome metal surface treatment agent further comprises:
Containing boric acid, the content of boric acid is 10 to 10 on a mass basis.
It is preferably 500 ppm.

The present invention also provides a non-chrome metal surface treatment method, which comprises the step (A) of treating an object with the above-mentioned non-chrome metal surface treatment agent. In the non-chromium metal surface treatment method, it is preferable that a step of washing with an acid is performed before the step (A) is performed. The above chromium-free metal surface treatment method includes the step (A)
It is preferable that a step of washing with an alkali and then a step of washing with an acid are performed before the step of.

The present invention is also an aluminum or aluminum alloy plate characterized by being obtained by the above chromium-free metal surface treatment method. The above-mentioned aluminum or aluminum alloy plate has a water-soluble zirconium compound and / or a water-soluble titanium compound (1) of 2 to 100 in terms of zirconium and / or titanium atoms, after being dried.
25 mg / ^{m 2,} and, it is preferable that tannin (2) is film of 5 to 100 mg / ^{m 2} containing a carbon atom in terms becomes formed. The present invention will be described in detail below.

The chromium-free metal surface treatment agent of the present invention is used as a pretreatment agent in the production of a thermoplastic polyester resin-coated metal plate. That is, when the above-mentioned thermoplastic polyester-based resin is coated on a metal plate treated with the chromium-free metal surface-treating agent of the present invention, the resin can be coated with good adhesiveness, and the thermoplastic polyester-based resin coating having good properties is coated. A metal plate can be manufactured.

The chromium-free metal surface treatment agent of the present invention contains a water-soluble zirconium compound and / or a water-soluble titanium compound (1). The water-soluble zirconium compound is not particularly limited as long as it is a compound containing zirconium, but stability at the pH is good,
A water-soluble zirconium compound containing fluorine is preferable because it has excellent film forming properties.

The water-soluble zirconium compound containing fluorine is not particularly limited, and examples thereof include H ₂ Zr.
_{F 6, (NH 4) 2} ZrF 6, K 2 ZrF 6, Na 2 Z
Examples thereof include rF ₆ and Li ₂ ZrF ₆ . These may be used alone or in combination of two or more.

The water-soluble titanium compound is not particularly limited as long as it is a compound containing titanium.
It has good stability in H and excellent film formation,
Water-soluble titanium compounds containing fluorine are preferred.

The water-soluble titanium compound containing fluorine is not particularly limited, and examples thereof include H ₂ TiF ₆ ,
(NH ₄ ) ₂ TiF ₆ , K ₂ TiF ₆ , Na ₂ TiF ₆
Etc. can be mentioned. These may be used alone or in combination of two or more.

The content of the water-soluble zirconium compound and / or the water-soluble titanium compound (1) in the non-chromium metal surface-treating agent is, based on the mass of zirconium and / or titanium, a lower limit of 20 ppm and an upper limit. Is 8
It is 00 ppm. If it is less than 20 ppm, a sufficient amount of zirconium or titanium coating cannot be obtained in a short time,
Adhesion decreases. When it exceeds 800 ppm, the adhesiveness is lowered, and the performance is not improved and the processing time is not shortened, resulting in an increase in cost. The lower limit is more preferably 100 ppm, and the upper limit is more preferably 300 ppm. The content of the water-soluble zirconium compound and / or the water-soluble titanium compound is
It is the total content of zirconium and titanium contained in the chromium-free metal surface treatment agent.

The chromium-free metal surface treating agent of the present invention contains tannin (2). The tannin (2) is also called tannic acid, and is a general term for aromatic compounds having a complex structure having a large number of phenolic hydroxyl groups widely distributed in the plant kingdom. The tannin (2) is
It may be hydrolyzable tannin or condensed tannin.

Examples of the tannin (2) include hamamelitannin, oyster tannin, chattannin, quintet tannin, gallic tannin, myrobalan tannin, dibidibitan tannin, argalovira tannin, valonia tannin and catechin tannin. Further, the tannin (2) may be a tannin decomposition product obtained by decomposing tannin existing in a plant by a method such as hydrolysis.

The tannin (2) is commercially available, for example, "tannic acid extract A", "B tannic acid", "N tannic acid", "technical tannic acid", "purified tannic acid", "Hi". "Tannic acid", "F tannic acid", "local tannic acid" (all manufactured by Dainippon Pharmaceutical Co., Ltd.),
"Tannic acid: AL" (manufactured by Fuji Chemical Industry Co., Ltd.) or the like can also be used. The above tannins may be used alone or in combination of two or more.

The tannin (2) has a number average molecular weight of 2
It is preferably 00 or more. When a tannin decomposition product is used as the tannin (2), when it is a low molecular weight compound having a molecular weight of less than 200 due to excessive progress of decomposition, it does not have properties as tannin, and therefore, it does not form a laminate film. Adhesion does not improve.

The above tannin (2) has a lower limit of 100 ppm and an upper limit of 40 in terms of mass in the chromium-free metal surface treatment agent.
It is contained in a ratio within the range of 00 ppm. When the tannin (2) is less than 100 ppm, the film adhesiveness is lowered, and even if the tannin (2) is blended in excess of 4000 ppm, the adhesiveness is not improved, which is not desirable in terms of cost. The above lower limit is more preferably 500 ppm, and 1000
More preferably, it is ppm. The upper limit is 300
It is more preferably 0 ppm, further preferably 2000 ppm.

The non-chromium metal surface treatment agent of the present invention is p
H is within the range of the lower limit of 1.4 and the upper limit of 4.0. When the pH is less than 1.4, the etching of the metal surface is promoted too much, so that the appearance of the coating becomes poor and the corrosion resistance of the obtained coating also deteriorates. If the pH exceeds 4.0, the chemical conversion reaction does not proceed satisfactorily, and it becomes difficult to form a film. The lower limit is more preferably 1.8 and even more preferably 2.2. The upper limit is more preferably 3.4 and even more preferably 2.8.

The chromium-free metal surface treatment agent of the present invention preferably further contains boric acid. By containing boric acid, the film formation rate is improved. When the film formation rate is improved, the surface treatment temperature can be lowered, which is preferable in that the energy efficiency is improved and the cost of the surface treatment is reduced. When blending the boric acid,
Content is based on the mass of the non-chromium metal surface treatment agent,
It is preferable that the lower limit is 10 ppm and the upper limit is 500 ppm. If it is less than 10 ppm, the effect of improving the film formation rate is not sufficiently exhibited. 500ppm
Even if the content exceeds 5, the effect is not improved, which is not desirable in terms of cost. The lower limit is more preferably 50 ppm, further preferably 80 ppm. The upper limit is more preferably 300 ppm, further preferably 200 ppm.

In addition to the above components, the non-chromium metal surface treating agent of the present invention may further contain an etching aid, a chelating agent and a pH adjusting agent, if necessary. Examples of the etching aids include hydrofluoric acid, hydrofluoric acid salts, and fluoroboric acid. When the water-soluble zirconium compound or the zirconium or titanium complex mentioned above as the water-soluble titanium compound (1) is used as a source of fluorine ions, the amount of fluorine ions produced is insufficient, It is preferable to use the above-mentioned fluorine compound in combination.

Examples of the chelating agent include acids such as citric acid, tartaric acid and gluconic acid which form a complex with aluminum and metal salts thereof.

Examples of the pH adjuster include nitric acid,
Examples thereof include acids or bases such as perchloric acid, sulfuric acid, sodium nitrate, ammonium hydroxide, sodium hydroxide and ammonia, which do not adversely affect the surface treatment.

The non-chrome metal surface treatment agent of the present invention is used for producing a thermoplastic polyester resin-coated metal plate. That is, the metal plate surface-treated with the chromium-free metal surface treatment agent of the present invention is used as a thermoplastic polyester resin-coated metal plate after a step of coating the thermoplastic polyester resin. The thermoplastic polyester resin coated metal plate is a laminate of a polyester resin on a metal plate, the surface is protected by a polyester resin layer, metal cans, aluminum foil containers, home appliances, home building materials. It can be used as a metal material for the like.

The thermoplastic polyester resin is not particularly limited, and is composed of, for example, constitutional units such as ethylene terephthalate unit, ethylene naphthalate unit, ethylene isophthalate unit, butylene terephthalate unit, 1,4 cyclohexanedimethanol terephthalate unit. A thermoplastic polyester resin can be mentioned. It may be a copolymerized thermoplastic polyester resin having two or more of the above structural units. A polyethylene terephthalate resin comprising ethylene terephthalate units or a polyethylene naphthalate resin comprising naphthalene terephthalate units is more preferred.

The above thermoplastic polyester resin may be laminated on a metal after forming a film,
The thermoplastic polyester resin that has been heated and melted may be extruded in a film shape by a slit having a narrow extruding width of an extrusion molding machine and directly laminated on a metal plate by direct lamination. When the film is laminated after being formed, the film is not particularly limited, and may be, for example, an unstretched film, a uniaxially stretched film, or a biaxially stretched film.

The non-chrome metal surface treatment method of the present invention comprises:
It comprises the step (A) of treating an object to be treated with the non-chromium metal surface treating agent. By performing the above step (A), excellent corrosion resistance and coating film adhesion can be imparted to the object to be treated.

The material to be treated by the non-chromium metal surface treatment method of the present invention includes, for example, a metal base material, and aluminum or aluminum alloy is preferable. For example, aluminum alloy 5182 material, aluminum alloy 5021 material, Aluminum alloy 5022 material, aluminum alloy 5052 material, aluminum alloy 3004
Material, aluminum alloy 3005 material, aluminum alloy 1
050 material, aluminum alloy 1100 material and the like are preferably used. The use of the material to be treated is not particularly limited,
For example, it can be used for home appliances, food and drink containers, housing construction materials, and the like.

The method of treating the object to be treated in the above-mentioned chromium-free metal treatment method is not particularly limited, and for example, a roll coating method, a dipping method, a spray method or the like can be used. A spray processing method is preferred. The treatment by the chromium-free metal surface treatment method of the present invention needs to be performed on the surface of the metal plate to be coated with the thermoplastic resin. Therefore, when the thermoplastic resin is coated on both sides, it is necessary to coat both sides.

In the step (A), the lower limit is 30 ° C. and the upper limit is 80.
It is preferably carried out in the temperature range of ° C. If the temperature is lower than 30 ° C., the reaction rate decreases and the film deposition property deteriorates.
In order to obtain a sufficient amount of film, it is necessary to extend the processing time, which lowers productivity. If it exceeds 80 ° C, energy loss may increase. The lower limit is 40 ° C
Is more preferable. The upper limit is more preferably 60 ° C.

In the step (A), when the treatment is carried out by the spray method, the treatment time is preferably within the range of the lower limit of 1 second and the upper limit of 20 seconds. If it is less than 1 second, the amount of film formed is not sufficient, and corrosion resistance and adhesion may be deteriorated. If it exceeds 20 seconds, etching during film formation may proceed excessively, resulting in poor adhesion and corrosion resistance. It may decrease. The lower limit is more preferably 3 seconds. The upper limit is more preferably 8 seconds.

After the step (A), a water washing treatment can be carried out if necessary. The above-mentioned washing treatment is performed once or more times so as not to adversely affect the appearance of the coating film and the like. In this case, the final washing with water is suitably performed with pure water. The above-mentioned water washing treatment may be either spray water washing or immersion water washing, and it is also possible to perform water washing by combining these methods.

The film obtained in the above step (A) is preferably washed with water and then dried. As a method for drying the film, heat drying is preferable, and examples thereof include oven drying and / or heat drying by forced circulation of hot air. These heat drying is usually 40 to 1
It is carried out at 20 ° C. for 6 seconds to 60 seconds.

The non-chromium metal surface treatment method of the present invention comprises:
It is preferable that a step of washing with an acid is performed before the treatment of the step (A). Further, it is preferable that a step of washing with alkali is performed before the step of washing with acid.
The most preferred embodiment is a method in which the steps of alkali washing, water washing, acid washing, water washing, non-chromium metal surface treatment, water washing, and drying are sequentially performed.

The alkali cleaning treatment is not particularly limited, and for example, the alkali cleaning conventionally used for alkali cleaning treatment of metals such as aluminum and aluminum alloy can be performed. In the alkaline cleaning treatment, the alkaline cleaning is usually performed using an alkaline cleaner. The acid cleaning is performed using an acid cleaner.

The above alkaline cleaner is not particularly limited, and for example, those which are used for usual alkaline cleaning can be used, and examples include "Surf Cleaner 360" manufactured by Nippon Paint Co., Ltd. The acid cleaner is not particularly limited, and examples thereof include inorganic acids such as sulfuric acid, nitric acid, hydrochloric acid; "Surf Cleaner ST160" manufactured by Nippon Paint Co., Ltd., and the like.

The above acid cleaning and alkali cleaning treatments are usually carried out by a spray method. After performing the above-mentioned acid cleaning or alkali cleaning treatment, water cleaning treatment is performed in order to remove the acid cleaning agent or alkali cleaning agent remaining on the surface of the base material.

The coating film produced by the non-chromium metal surface treatment method of the present invention has a lower limit of 2 mg / molar amount of the water-soluble zirconium compound and / or the water-soluble titanium compound (1) in terms of zirconium and / or titanium atom, after being dried. m
² , the upper limit is 25 mg / m ² , and the tannin (2) is 5 mg / m ^{2 in} terms of carbon atom and 10 in upper limit.
It is preferably contained within the range of 0 mg / m ² . The amount of zirconium and titanium contained in the water-soluble zirconium compound and / or the water-soluble titanium compound (1) in the film can be measured by a fluorescent X-ray analyzer, and the amount of the tannin (2) can be determined depending on the form. It can be measured by the amount of organic carbon measured by a carbon / water content analyzer.

In the film obtained by the above-mentioned non-chrome metal surface treatment method, the film amount of each component can be obtained by appropriately setting the composition of the non-chrome metal surface treatment agent, the treatment temperature and the treatment time. .

The aluminum or aluminum alloy of the present invention is obtained by the above-mentioned non-chromium metal surface treatment method. The aluminum or aluminum alloy thus obtained has excellent corrosion resistance and adhesion, and thus can be suitably used for applications such as food and drink containers, home appliances, and housing building materials.

The method for adhering the film to the surface-treated metal plate thus obtained is not particularly limited, and for example, a method usually used for lamination can be used. For example, the film is fitted to the surface-treated metal plate. And place it on a heating roller, etc.
A method of bonding by thermocompression bonding for 0.1 to 10 seconds can be mentioned. Further, if necessary, after the film is pressure-bonded, it may be reheated (remelt, 5 seconds to 60 seconds) up to near the softening point (180 to 260 ° C.) of the film.

The non-chrome metal surface treatment agent of the present invention is excellent in workability and stability during treatment, and the obtained polyester resin-coated metal plate has sufficient adhesion. Therefore, the non-chrome metal surface treating agent of the present invention can be suitably used for producing a polyester resin-coated metal plate.

[0047]

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. In the examples, "parts" means "parts by mass" unless otherwise specified.

Example 1 9996.6 parts of ion-exchanged water was placed in a vessel equipped with a stirrer. "Zirconium fluoride hydrofluoric acid" manufactured by Nippon Light Metal Co., Ltd. (17.6 as Zr while stirring at room temperature)
%) 1.2 parts were gradually added. Further, 0.2 part of hydrofluoric acid was gradually added with stirring. Further, 2.0 parts of "tannic acid extract A" (nonvolatile content 50%) manufactured by Dainippon Pharmaceutical Co., Ltd. was gradually added with stirring. While stirring, ammonia was added to adjust the pH of the treating agent to 2.
Adjusted to 4. Stirring was continued for 10 minutes to obtain a slightly brown aqueous solution containing 21 ppm of zirconium hydrofluoric acid, 11 ppm of hydrofluoric acid (HF), and 100 ppm of tannin.

Examples 2 to 3 and Comparative Examples 1 to 4 Non-chromium metal surface treatments of Examples 2 to 4 and Comparative Examples 1 to 4 by the same method as in Example 1 with the compounding ratios shown in Tables 1 and 2. The agent was prepared.

Example 5 9997.1 parts of ion-exchanged water was placed in a vessel equipped with a stirrer. While stirring at room temperature, Morita Chemical Industry Co., Ltd.
0.7 parts of "titanium hydrofluoride" (containing 29.3% of Ti) manufactured by the company was gradually added. Furthermore, while stirring
0.2 parts of hydrofluoric acid was gradually added. Furthermore, while stirring, "tannic acid extract A" manufactured by Dainippon Pharmaceutical Co., Ltd.
2.0 parts (nonvolatile content 50%) was gradually added. With stirring, ammonia was added to adjust the pH of the treating agent to 2.8. Stirring is continued for 10 minutes, and titanium hydrofluoric acid is converted to titanium at 20 ppm and hydrofluoric acid (HF) is added at 11 ppm.
A slightly brown aqueous solution containing 100 ppm of tannin and 100 ppm was obtained.

Examples 6 to 8 and Comparative Examples 5 to 8 The chromium-free metal surface treatments of Examples 6 to 8 and Comparative Examples 5 to 8 were carried out by the same method as in Example 5 with the compounding ratios shown in Tables 1 and 2. The agent was prepared.

Example 9 9995.9 parts of ion-exchanged water was placed in a vessel equipped with a stirrer. With stirring at room temperature, 1.2 parts of zirconium hydrofluoric acid and 0.7 parts of hydrofluoric titanium titanate were gradually added. Further, 0.2 part of hydrofluoric acid was gradually added with stirring. Further, while stirring, "tannic acid extract A" manufactured by Dainippon Pharmaceutical Co., Ltd. (nonvolatile content 50
%) 2.0 parts was gradually added. Ammonia was added with stirring to adjust the pH of the treating agent to 2.6. 10
Stirring was continued for 21 minutes, and zirconium hydrofluoric acid was 21 ppm, titanium hydrofluoric acid was 20 ppm as titanium, hydrofluoric acid (HF) was 11 ppm,
A slightly brown aqueous solution containing 100 ppm of tannin was obtained.

Examples 10 to 12 and Comparative Examples 9 to 10 Non-chromium metal surface treatments of Examples 10 to 12 and Comparative Examples 9 to 10 were carried out by the same method as in Example 9 with the compounding ratios shown in Tables 1 and 2. The agent was prepared.

Example 13 9992 parts of ion-exchanged water was placed in a vessel equipped with a stirrer. While stirring at room temperature, 5.7 parts of zirconium hydrofluoric acid was gradually added. Further, 0.2 part of hydrofluoric acid was gradually added with stirring. Furthermore, 0.1 part of boric acid was gradually added with stirring. While stirring
2.0 parts of "tannic acid extract A" (nonvolatile content 50%) manufactured by Dainippon Pharmaceutical Co., Ltd. was gradually added. Ammonia was added with stirring to adjust the pH of the treating agent to 2.4.
Stirring is continued for 10 minutes, and zirconium hydrofluoric acid is 100 ppm, hydrofluoric acid (HF) is 11 ppm, boric acid is 10 ppm, and tannin is 100 pp.
A slightly brown aqueous solution containing m was obtained.

Examples 14 to 15 Non-chromium metal surface treating agents of Examples 14 to 15 were prepared by the same method as in Example 13 with the compounding ratios shown in Tables 1 and 2.

Example 16 998.9 parts of ion-exchanged water was charged into a vessel equipped with a stirrer. While stirring at room temperature, 5.7 parts of zirconium hydrofluoric acid was gradually added. Further, 0.2 part of hydrofluoric acid was gradually added with stirring. Further, with stirring, 5.0 parts of "B tannic acid" (powder) manufactured by Dainippon Pharmaceutical Co., Ltd. was gradually added and completely dissolved. While stirring, ammonia was added to adjust the pH of the treating agent to 2.4.
Adjusted to. Stirring was continued for 10 minutes to obtain a slightly brown aqueous solution containing zirconium hydrofluoric acid as zirconium of 100 ppm, hydrofluoric acid (HF) of 11 ppm and tannin of 500 ppm.

Example 17 998.9 parts of ion-exchanged water was placed in a vessel equipped with a stirrer. While stirring at room temperature, 5.7 parts of zirconium hydrofluoric acid was gradually added. Further, 0.2 part of hydrofluoric acid was gradually added with stirring. Furthermore, while stirring, Dainippon Pharmaceutical Co., Ltd. "Hi tannic acid"
5.0 parts of (powder) was gradually added and completely dissolved.
Ammonia was added with stirring to adjust the pH of the treating agent to 2.4. Stirring is continued for 10 minutes, and zirconium hydrofluoric acid is used as zirconium at 100 ppm, hydrofluoric acid (HF) is 11 ppm, and tannin is 500 pp.
A slightly brown aqueous solution containing m was obtained.

Example 18 9984.3 parts of ion-exchanged water was placed in a vessel equipped with a stirrer. While stirring at room temperature, 5.7 parts of zirconium hydrofluoric acid was gradually added. While stirring, 10 parts of "tannic acid extract A" manufactured by Dainippon Pharmaceutical Co., Ltd. was gradually added and completely dissolved. Ammonia was added with stirring to adjust the pH of the treating agent to 2.4. Stirring was continued for 10 minutes to obtain a light brown aqueous solution containing zirconium hydrofluoric acid as zirconium of 100 ppm and tannin of 500 ppm.

Examples 19 to 22 and Comparative Examples 11 to 12 Aqueous solutions prepared in Example 2 (100 ppm of tannin and 500 ppm of fluorinated zirconium hydrofluoric acid as zirconium).
The pH (containing ppm) was adjusted within a range of 1.2 to 5 using nitric acid or ammonia to obtain non-chromium metal surface treatment agents of Examples 19 to 22. (Example 19: pH =
1.4, Example 20: pH = 2.0, Example 21: pH
= 3.0, Example 22: pH = 4.0) The non-chrome metal surface treating agents of Comparative Examples 11 and 12 were obtained by the same method. (Comparative Example 11: pH = 1.2, Comparative Example 12: pH = 5.0)

Examples 23 to 26, Comparative Examples 13 to 14 Aqueous solutions prepared in Example 6 (containing 100 ppm of tannin fluoride and 100 ppm of tannin).
PH of 1.2-5 with nitric acid or ammonia
It adjusted in the range of and obtained the non-chromium metal surface treatment agent of Examples 23-26. (Example 23: pH = 1.4, Example 24: pH = 2.0, Example 25: pH = 3.0, Example 26: pH = 4.0) Comparative Examples 13 and 14 by the same method. A non-chrome metal surface treatment agent was obtained. (Comparative Example 13: pH = 1.2, Comparative Example 14: pH = 5.0)

(Preparation of surface-treated plate) Aluminum alloy 3
Both sides of the 004 plate material were washed with a 1% diluted solution of "Surf Cleaner 360", an alkaline cleaner manufactured by Nippon Paint Co., Ltd. (65 ° C x 3 seconds), washed with water, and then with 1% sulfuric acid.
It was washed with a diluting solution (50 ° C. × 3 seconds) and washed with water, and the obtained aluminum material was treated with the non-chromium metal surface treatment agent of the above-mentioned Examples and Comparative Examples for 5 seconds by a spraying device, and the material temperature was changed. Dry at 80 ° C for 30 seconds,
A surface-treated metal plate was obtained. The treatment temperatures during the surface treatment are shown in Tables 1 and 2.

Comparative Example 15 Using "Alsurf 401/45" manufactured by Nippon Paint Co., Ltd., a phosphoric acid chromate-treated aluminum material was prepared.

(Measurement of coating amount) The masses of zirconium, titanium, and chromium of the dried coating films obtained in Examples and Comparative Examples were measured by a fluorescent X-ray analyzer "XRF-1" manufactured by Shimadzu Corporation.
700 ". The mass of tannin in the dried chemical conversion film was determined by measuring the mass of carbon atoms derived from tannin using a carbon / water content analyzer “RC412” manufactured by LECO, USA.

Zr is the mass of zirconium in the zirconium compound obtained by the above measurement, Ti is the mass of titanium in the titanium compound, and C is the mass of carbon atoms derived from tannin. Indicated.

[0065]

[Table 1]

[0066]

[Table 2]

(Preparation of Laminated Plate) A polyethylene terephthalate (PET) film was placed on the obtained surface-treated metal plate, and a roll temperature of 180 was applied using a heating roller.
After pressure-bonding at a temperature of 30 ° C. and a roll speed of 30 m / min, a laminate plate was obtained by heating at a material temperature of 240 ° C. for 60 seconds using a conveyor type oven to bond them.

(Evaluation method) The following evaluations were performed and the results are shown in Table 3.
And shown in Table 4. 1. Stability of Surface Treatment Agent The surface treated metal agent prepared above was stored at 40 ° C. for 30 days, and the appearance of the treatment liquid was visually evaluated. In Tables 3 and 4, those having a good appearance without any abnormalities such as cloudiness, sedimentation and the presence or absence of aggregates were represented by “◯”, and those having abnormalities were represented by the state.

2. Appearance of coating film The surface of the surface-treated metal plate obtained above was visually evaluated. In Tables 3 and 4, those having a good appearance without repellency, unevenness, remarkable discoloration and the like were indicated by "◯", and those having an abnormality were indicated by the state.

3. Adhesion of Laminated Plate Regarding the laminated plate obtained as described above, the following (1) to
A tape peeling test was performed as in (6), and the adhesion was evaluated by the number of grids that were not peeled off by the tape among 100 grids before the tape was attached. (1) Plane / Untreated In accordance with JIS K 5400.8.5.1, PET
A cross-cut was cut on the surface to which the film was attached and a tape peeling test was performed. (2) Flat / Boiling Water Treatment The laminated plate was dipped in boiling water for 30 minutes, a cross-cut was cut on the surface on which the PET film was attached, and a tape peeling test was performed. (3) The flat / steam-treated laminated plate was placed in pressurized steam at 125 ° C. and 1.13 atm for 30 minutes, and a cross-cut was cut on the surface on which the PET film was attached, and a tape peeling test was performed. The absence of peeling points was regarded as a passing level.

(4) An Erichsen processed / untreated laminate plate was subjected to a cross-cut with a cross-cut, and the cut surface was extruded by 4 mm with an Erichsen extrusion tester to perform a tape peeling test. (5) Erichsen processing / boiling water treatment A laminated plate was immersed in boiling water for 30 minutes, a cross-cut was cut on the surface on which the PET film was attached, and the cut surface was extruded by 4 mm with an Erichsen extrusion tester to perform a tape peeling test. . (6) Erichsen processing / steam treatment Laminated plate was placed in pressurized steam at 125 ° C and 1.13 atm for 30 minutes, put a cross cross cut on the PET film pasting surface, and cut the surface with an Erichsen extrusion tester to 4 mm. Extrusion and tape peeling tests were performed.

[0072]

[Table 3]

[0073]

[Table 4]

The polyester resin-coated metal sheet of the example which has been surface-treated with the chromium-free metal surface-treating agent of the present invention is excellent in all properties of the treating agent stability, film appearance, and physical properties of the laminate material. A polyester resin-coated metal plate having excellent adhesion without using chromium metal has been obtained. Further, the non-chromium metal surface-treating agents of Examples 13 to 15 containing boric acid are similar to Example 2 except that boric acid is not added, and the same non-chromium metal surface-treating treatment is performed at a lower reaction temperature. You can

On the other hand, either the water-soluble zirconium compound and / or the water-soluble titanium compound (1) or the tannin (2) is not contained, or the content is within the scope of the present invention. None of the non-chromium metal surface-treating agents of Comparative Examples 1 to 10 and Comparative Examples 11 to 14 in which the solution pH is outside the range of the present invention cannot perform the desired metal surface treatment, and thus the obtained thermoplastic The polyester resin-coated metal plate is inferior in adhesiveness, and the adhesiveness after the boiling water treatment and the steam treatment is largely reduced.

[0076]

The metal plate treated with the non-chromium metal surface treatment agent of the present invention is suitable for use in a thermoplastic polyester resin-coated metal plate, and the thermoplastic polyester resin-coated metal plate has a film-metal plate adhesion property. It has excellent properties.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masayuki Kamimura             4-1-1 Minami-Shinagawa, Shinagawa-ku, Tokyo Japan             Within Paint Co., Ltd. (72) Inventor Minoru Inoue             4-1-1 Minami-Shinagawa, Shinagawa-ku, Tokyo Japan             Within Paint Co., Ltd. F-term (reference) 4D075 BB73X CA13 DA06 DB07                       DB48 DC42 EC02 EC54                 4K026 AA09 AA22 BA08 BB06 BB10                       CA13 CA28 CA37 CA38 DA06                       DA11 EA07 EA08

Claims (7)

[Claims] 1. A non-chromium metal surface treating agent comprising a water-soluble zirconium compound and / or a water-soluble titanium compound (1) and a tannin (2), wherein the water-soluble zirconium compound and / or the water-soluble titanium compound is used. The content of (1) is 20 to 800 ppm on a mass basis as the amount of zirconium and / or titanium, and the content of the tannin (2) is 100 to 4000 p on a mass basis.
The non-chromium metal surface treating agent has a pH of 1.4 to 4.0 and is used for producing a thermoplastic polyester resin-coated metal plate. 2. The non-chromium metal surface treatment agent according to claim 1, further comprising boric acid, and the content of boric acid is 10 to 500 ppm on a mass basis. 3. A non-chromium metal surface treatment method comprising a step (A) of treating an object with the non-chromium metal surface treatment agent according to claim 1. 4. The non-chromium metal surface treatment method according to claim 3, wherein a step of washing with an acid is carried out before the step (A) is carried out. 5. The non-chromium metal surface treatment method according to claim 3, wherein before the step (A), a step of washing with an alkali and then a step of washing with an acid are performed. 6. An aluminum or aluminum alloy plate obtained by the non-chrome metal surface treatment method according to claim 3, 4, or 5. 7. The water-soluble diene in terms of mass per one side after drying.
Ruconium compound and / or water-soluble titanium compound (1)
2 to 25 m in terms of zirconium and / or titanium atoms
g / m^Two, And tannin (2) in terms of carbon atoms of 5
~ 100 mg / m ^TwoClaim formed by containing film
Item 7. The aluminum or aluminum alloy plate according to item 6.