Coated metal material having coating film and method for producing same

Abstract

The invention provides a novel method for improving the corrosion resistance of a coated metal material. The present invention relates to a coated metal material having a coating film and a method for manufacturing the same, the coated metal material having a coating film being obtained by bringing a treatment agent into contact with a chemical conversion coating film of a metal material having a chemical conversion coating film and then coating the chemical conversion coating film, the treatment agent contains a compound or polymer (A) that exhibits water solubility or water dispersibility, and the compound or polymer (A) is selected from one or more compounds or polymers having-NH2, compounds or polymers having-NH2 and-NH-, and compounds or polymers having-NH-.

Description

Technical Field

[0001] The present invention relates to a treatment agent for post-treatment of a chemical conversion treatment, and a metal material having a coating film. The chemical conversion treatment is to form a chemical conversion film on the surface of the metal material or on the surface of the metal material. Background Art

[0002] Various chemical conversion treatment agents and surface treatment agents have been developed to improve the corrosion resistance of coated metal materials. For example, Patent Document 1 discloses a pretreatment agent for metal materials used for pretreatment of chemical conversion treatment. The pretreatment agent comprises a specific polymer and water.

[0003] In addition, Patent Document 2 discloses a method for performing anti-corrosion pretreatment on a metal surface comprising steel, galvanized steel, aluminum, magnesium and / or a zinc-magnesium alloy, wherein the metal surface is contacted with an aqueous composition A and an acidic aqueous composition B, wherein the aqueous composition A contains a specific amount of a copolymer containing specific monomer units, and the acidic aqueous composition B contains at least one compound selected from a titanium compound, a zirconium compound and a hafnium compound.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: International Publication No. 2019 / 087320;

[0007] Patent Document 2: Japanese Patent Application Publication No. 2019-518874. Summary of the Invention

[0008] Problems to be solved by the invention

[0009] In order to improve the corrosion resistance of coated metal materials, although the above-mentioned pretreatment agent solution has been proposed, other methods still need to be developed. The problem to be solved by the present invention is to provide a new method for improving the corrosion resistance of coated metal materials.

[0010] Solutions for solving problems

[0011] The present inventors have conducted intensive studies to solve the above-mentioned problems and have found that by performing post-chemical conversion treatment using a treatment agent containing a polymer having a specific structure, a metal material having a coating film formed after the post-chemical conversion treatment has excellent corrosion resistance, thereby completing the present invention.

[0012] A method for solving the above-mentioned problem is as follows.

[0013] [1] A treatment agent used for post-treatment of a chemical conversion treatment, wherein the chemical conversion treatment is to form a chemical conversion film on the surface of a metal material or on the surface thereof.

[0014] The above-mentioned treatment agent contains a water-soluble or water-dispersible compound or polymer (A), and the above-mentioned compound or polymer (A) is selected from one or more compounds or polymers having -NH2, compounds or polymers having -NH2 and -NH-, and compounds or polymers having -NH-.

[0015] [2] The treatment agent according to [1], further comprising at least one metal acid ion (B) selected from molybdate ions and / or tungstate ions.

[0016] [3] A metal material having a coating film, which is obtained by bringing the treatment agent described in [1] or [2] into contact with the chemical conversion film of a metal material having a chemical conversion film, and then coating the metal material.

[0017] Effects of the Invention

[0018] According to the present invention, a treatment agent and a metal material having a coating can be provided. The treatment agent can improve corrosion resistance when a coating is formed on a chemical conversion film. The metal material having a coating is obtained by bringing the treatment agent into contact with the chemical conversion film of the metal material having a chemical conversion film and then coating the metal material. DETAILED DESCRIPTION

[0019] The treatment agent of an embodiment of the present invention is used for post-treatment after chemical conversion treatment, wherein the chemical conversion treatment is to form a chemical conversion film on the surface of a metal material. The treatment agent is also a coating pretreatment agent. That is, the treatment agent is used after the chemical conversion treatment and before coating. The treatment agent is combined with a water-soluble or water-dispersible compound or polymer (A), wherein the compound or polymer (A) is selected from one or more of a compound or polymer having -NH2, a compound or polymer having -NH2 and -NH-, and a compound or polymer having -NH-.

[0020] Hereinafter, the treatment agent of this embodiment, the post-treatment method of the metal material using the treatment agent, and the manufacturing method of the metal material with a chemical conversion film are described in order. In addition, the present invention can be arbitrarily modified within the scope of its purpose and is not limited to the specific embodiment described below.

[0021] <Compound or polymer (A)>

[0022] The compound or polymer (A) comprises one or more compounds or polymers selected from compounds or polymers having -NH2, compounds or polymers having -NH2 and -NH-, and compounds or polymers having -NH-. Furthermore, the compounds or polymers are all water-soluble or water-dispersible, and may have a branched chain, a cyclic structure, or both a branched chain and a cyclic structure. The polymer may be a homopolymer or a copolymer. Furthermore, homopolymers and copolymers may also form salts. Examples of salts include hydrochlorides, sulfates, acetates, and the like. Furthermore, "water-dispersible" refers to wettability to water.

[0023] As a compound or polymer having -NH2, there is no particular limitation as long as at least a part of the substituents of the subunits of the compound or polymer has -NH2, and examples thereof include, but are not limited to, methylamine, ethylamine, isopropylamine, ethylenediamine, 3,3-dimethyl-2-butylamine, sec-butylamine, polyethyleneamine, polyallylamine, etc.

[0024] As a compound or polymer having -NH2 and -NH-, there is no particular limitation as long as at least a part of the substituents of the subunits of the compound or polymer have -NH2 and -NH-, and examples thereof include: diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, N,N'-bis(2-aminoethyl)-1,3-propylenediamine, N,N'-bis(3-aminopropyl)ethylenediamine, polyethyleneimine, hexaethyleneheptamine, heptaethyleneoctamine, nonaethylenedecaamine, etc., but are not limited thereto.

[0025] The compound or polymer having -NH- is not particularly limited as long as at least a part of the substituents of the subunits of the compound or polymer has -NH-. Examples thereof include, but are not limited to, dimethylamine, diethylamine, N-ethylmethylamine, N-methylisopropylamine, diisopropylamine, polydiallylamine, cationic acrylic resins, and cationic polyurethane resins.

[0026] The copolymer is not particularly limited as long as it contains, for example, vinylamine, allylamine, diallylamine, etc. Examples include copolymers of allylamine and diallylamine, copolymers of vinylamine and allylamine, and copolymers of vinylamine and diallylamine. In addition, copolymers containing cationic polyurethane polymers can also be used. Furthermore, the copolymer may be an alternating copolymer, a random copolymer, a block copolymer, or a graft copolymer.

[0027] In the treatment agent of this embodiment, one or more of the above-mentioned compounds or polymers (A) can be used. Examples of combinations of two or more thereof include, but are not limited to, polyallylamine and polyethyleneimine, polyallylamine and polydiallylamine, polyallylamine and polyethyleneamine, polyethyleneimine and polydiallylamine, polyethyleneimine and polyethyleneamine, and polydiallylamine and polyethyleneamine.

[0028] The weight average molecular weight of the compound or polymer (A) used in the present embodiment is usually 60 to 300,000, and preferably 60 to 100,000.

[0029] When polyallylamine is used as the water-soluble or water-dispersible polymer having -NH2, the weight average molecular weight of the polyallylamine may be approximately 300 to 5000.

[0030] When polyethyleneimine is used as the water-soluble or water-dispersible polymer having -NH2 and -NH-, the weight average molecular weight of the polyethyleneimine may be approximately 300 to 100,000.

[0031] When polydiallylamine is used as the water-soluble or water-dispersible polymer having -NH-, the weight average molecular weight of the polydiallylamine may be approximately 300 to 50,000.

[0032] When a cationic polyurethane resin is used as the water-soluble or water-dispersible polymer having the -NH- group, the weight average molecular weight of the cationic polyurethane resin may be approximately 1,000 to 1,000,000.

[0033] In addition, the weight average molecular weight is a value measured by GPC (gel permeation chromatography) in terms of polystyrene.

[0034] The amount of the compound or polymer (A) that can be used to prepare the treatment agent of this embodiment is not particularly limited, but is preferably in the range of 1 to 20,000 mg / L in terms of solid content, and more preferably in the range of 5 to 10,000 mg / L in terms of solid content, relative to the total amount of the treatment agent.

[0035] <Metal Acid Ion (B)>

[0036] The treatment agent of the present embodiment preferably contains at least one metal acid ion (B) selected from molybdate ions and / or tungstate ions. The supply source of the metal acid ion (B) is not particularly limited as long as it is a substance that can provide the metal acid ion (B) by mixing in an aqueous medium. For example, sodium molybdate, ammonium molybdate, potassium molybdate, lithium molybdate, calcium molybdate, sodium tungstate, ammonium tungstate, potassium tungstate, lithium tungstate, calcium tungstate, etc. can be mentioned. Only one of these can be used, or two or more can be used.

[0037] The content of the metal acid ion (B) in the treatment agent is not particularly limited, but is usually in the range of 0.01 to 1000 mmol / L, preferably in the range of 0.1 to 500 mmol / L, calculated as molybdenum and / or tungsten.

[0038] (Organic acid)

[0039] The treatment agent of the present embodiment may further contain the following organic acid: When the treatment agent of the present embodiment further contains an organic acid, the effect of the present invention is further enhanced.

[0040] The organic acid is not particularly limited, and may be, for example, an organic acid having 3 or less carbon atoms and having one carboxyl group and / or methylsulfonyl group. Specific examples of the organic acid having 3 or less carbon atoms and having one carboxyl group and / or methylsulfonyl group include formic acid, acetic acid, lactic acid, propionic acid, trifluoroacetic acid, methanesulfonic acid, and trifluoromethanesulfonic acid.

[0041] The treatment agent of this embodiment can use one or more of the above-mentioned organic acids. Examples of combinations of two or more organic acids include formic acid and acetic acid, formic acid and lactic acid, formic acid and methanesulfonic acid, acetic acid and lactic acid, acetic acid and methanesulfonic acid, and lactic acid and methanesulfonic acid.

[0042] The amount of the organic acid to be added is not particularly limited, but is preferably in the range of 10 to 10,000 mg / L, more preferably in the range of 100 to 5,000 mg / L, relative to the total amount of the treatment agent.

[0043] The pH of the treatment agent of the present embodiment is not particularly limited, and is generally above 7.0, may be above 8.0, may be above 9.0, may be above 10.0, and is generally below 14.0, may be below 13.0, or may be below 12.0. Here, the pH in this specification is the value measured for the treatment agent at 25°C using a pH meter. In order to make the pH of the treatment agent within the above range, a pH adjuster may also be used. There is no particular limitation on the pH adjuster that can be used when it is desired to increase the pH, and preferably, for example, an aqueous solution of sodium hydroxide, an aqueous solution of potassium hydroxide, aqueous ammonia, triethanolamine, triethylamine, etc. On the other hand, there is no particular limitation on the pH adjuster that can be used when it is desired to lower the pH, and preferably, for example, formic acid, acetic acid, nitric acid, lactic acid, methanesulfonic acid, etc. In addition, one or more of these pH adjusters may be used.

[0044] The treatment agent of the present embodiment can be prepared into liquid.For the manufacture method of this liquid, there is no particular restriction, for example, can coordinate above-mentioned compound or polymer (A) and water to prepare, can also further coordinate the supply source of above-mentioned metal acid radical ion (B), above-mentioned organic acid to prepare as needed.As liquid medium, there is no particular restriction, preferably water (deionized water, distilled water).In addition, as liquid medium, as long as above-mentioned compound or polymer (A) can dissolve or disperse, then can use the mixed solvent that hydrophilic solvent (such as lower alcohol) is mixed with water.

[0045] In addition, when the treatment agent of the present embodiment is used to post-process the metal material with the chemical conversion film, there is sometimes a part of the metal material with the chemical conversion film that dissolves, and the metal component is mixed into the treatment agent. Therefore, the treatment agent can also include metal components such as Fe, Zn, Al, and Mg. In addition, for components that are inevitably mixed in operation, such as Zr, the same is true. These components can be inevitably mixed into the treatment agent, or the treatment agent can be intentionally made to include these components. Moreover, as an example of an acid component whose source is a counter ion of a compound used for adjusting the above-mentioned metal component and whose source is an acid compound used for adjusting pH, carbonate ions, nitrate ions, silicate ions, sulfonate ions, etc. can be mixed in as an anion component of an acid or salt.

[0046] (Post-processing method of metal materials)

[0047] Another embodiment of the present invention relates to a post-treatment method comprising bringing the above-mentioned treatment agent into contact with a metal material having a chemical conversion film.

[0048] The post-treatment method includes a post-treatment step in which a treatment agent according to an embodiment of the present invention is brought into contact with the surface of, or on the surface of, a metal material having a chemical conversion coating. Furthermore, the post-treatment step may include water washing the metal material having the chemical conversion coating. Furthermore, the post-treatment step may include water washing the metal material having the chemical conversion coating before the post-treatment step and after the chemical conversion treatment step.

[0049] Furthermore, a pretreatment process may be included before the chemical conversion process. Before the pretreatment process, a degreasing process called degreasing may be included to remove oil and attachments on the surface of the metal material. The degreasing process is not particularly limited, and a known method can be applied. Water washing may or may not be performed after the degreasing process. Furthermore, before the pretreatment process, a pickling process and / or an oxide film removal process called pickling may be included to remove iron oxide, zinc oxide, etc. on the surface of the metal material. The method of the pickling process and / or the oxide film removal process is not particularly limited, and a known method can be applied.

[0050] Methods for contacting the metal material having a chemical conversion coating with the treatment agent include known contact methods such as immersion treatment, spray treatment, flow coating, or combinations thereof. Contact with the treatment agent is preferably performed at a predetermined temperature for a predetermined time. The contact temperature is preferably 5°C to 60°C, more preferably 10°C to 50°C, but is not limited to these temperatures. Furthermore, the contact time is preferably 5 to 600 seconds, more preferably 10 to 300 seconds, but is not limited to these treatment times.

[0051] Another embodiment of the present invention also relates to a method for producing a metal material having a chemical conversion film, which includes a chemical conversion treatment step of forming a chemical conversion film on the metal material before bringing the treatment agent into contact with the surface of the metal material.

[0052] The chemical conversion treatment process is not particularly limited as long as it is a process for forming a chemical conversion film, and examples thereof include a zirconium chemical conversion treatment process, a titanium chemical conversion treatment process, a hafnium chemical conversion treatment process, and a vanadium chemical conversion treatment process. The various chemical conversion treatment processes mentioned above may be performed in a single process, or may be combined and performed in sequence in two or more processes. In addition, when combining a plurality of the two or more processes mentioned above, water washing may be performed after the various subsequent processes, or water washing may not be performed, or a portion of the water washing may be omitted. The treatment temperature and contact time in the chemical conversion treatment process can be appropriately set according to the type of chemical conversion treatment process, the concentration of the chemical conversion treatment agent, and the like.

[0053] Embodiments of the present invention also relate to a method for manufacturing a coated metal material comprising a coating process, wherein the coating process is performed on the surface of the metal material having the chemical conversion film or the chemical conversion film that has been subjected to post-chemical conversion treatment. In addition, it also relates to a coated metal material having a coating film on the surface of the metal material having the chemical conversion film obtained by the above-mentioned manufacturing method. The coating method is not particularly limited, and known methods such as roller coating, electrophoretic coating (such as cationic electrophoretic coating), spraying, thermal spraying, airless spraying, electrostatic coating (such as electrostatic powder coating), roller coating, thin film flow coating (Curtain flow coating), brushing, rod coating, flow dipping method, etc. can be applied. In addition, a drying process (including a sintering process, a curing process) etc. can be performed after the coating process to dry the coating on the surface of the coated metal material.

[0054] Furthermore, the surface of the metal material having the chemical conversion film or the chemical conversion film that has undergone post-chemical conversion treatment may or may not be washed before the coating process. Furthermore, the surface of the metal material having the chemical conversion film, either washed or unwashed, may or may not be dried before the coating process.

[0055] As above-mentioned coating, for example can be enumerated: oily paint, cellulose derivative coating, phenolic resin coating, alkyd resin coating, aminoalkyd resin coating, urea resin coating, unsaturated resin coating, vinyl resin coating, acrylic resin coating, epoxy resin coating, polyurethane resin coating, silicone resin coating, fluororesin coating, rust-proof coating, antifouling coating, powder coating, cationic electrophoretic coating, anionic electrophoretic coating, water-based coating, solvent coating etc. known coating.In addition, coating process can use identical or different various coatings to carry out 1 coating, also can carry out 2 or more coating.In addition, drying process is the process that makes the coating of coating dry, solidify.As drying method, for example can be enumerated: natural drying, reduced pressure drying, convection heat drying (for example, natural convection heat drying, forced convection heat drying), radiation type drying (for example, near infrared drying, far infrared drying), ultraviolet curing drying, electron beam curing drying, airflow curing (Vapor-cure, Bepocur), sintering drying etc. drying methods. In addition, these drying methods may be carried out alone or in combination of two or more.

[0056] As the above-mentioned cationic electrophoretic coating, a well-known method can be applied. For example, the following method can be cited: as a coating, a cationic electrophoretic coating containing an epoxy resin amine adduct and a blocked polyisocyanate curing agent as a curing component is used, and the metal material having a chemical conversion film is immersed in the coating. Cationic electrophoretic coating is carried out, for example, by maintaining the temperature of the coating at a specified temperature, stirring the coating, and applying a voltage to the metal material having the chemical conversion film in the cathode direction using a rectifier. The metal material thus subjected to cationic electrophoretic coating is washed with water and sintered, thereby forming a coating film on the chemical conversion film. Sintering is carried out for a certain time within a specified temperature range. Specifically, it is carried out at 170°C for 20 minutes. In addition, when a cationic electrophoretic coating method using a cationic electrophoretic coating is applied, it is preferred that the sodium ion concentration in the treatment agent used in, for example, a degreasing process, a pretreatment process, various chemical conversion treatment processes, and a chemical conversion post-treatment process be controlled to be less than 500ppm on a mass basis.

[0057] As coating methods using powder coating, such as spraying, electrostatic powder coating, and flow dipping, known methods can be applied. Examples of powder coatings include polyester resins and, as curing agents, blocked isocyanate curing agents, β-hydroxyalkylamide curing agents (see, for example, Japanese Patent Application Laid-Open No. 2011-88083), or triglycidyl isocyanurate. Sintering is performed within a specified temperature range for a specified time. Specifically, it is performed at 150-250°C for 20 minutes.

[0058] Known coating methods such as spraying, electrostatic coating, and bar coating using the solvent coating described above can be applied. Examples of solvent coatings include those containing resins such as melamine resins, acrylic resins, polyurethane resins, and polyester resins, and organic solvents such as thinners. Sintering is performed within a specified temperature range for a specified time. Specifically, it is performed at 130°C for 20 minutes.

[0059] The coating film obtained by the coating process may be a single layer or multiple layers. In the case of multiple layers, the coating materials used to form the various coating films, the coating method using the coating materials, the drying method of the coated metal materials, etc. may be the same or different.

[0060] In this embodiment, the types of metal materials that can be used as the target of the post-treatment process are not particularly limited. Examples include: steel materials (such as cold-rolled steel sheets, hot-rolled steel sheets, high-tensile steel sheets, tool steels, alloy tool steels, ductile iron, gray cast iron, etc.); plated materials, such as galvanized materials (such as electroplated zinc, hot-dip galvanized, etc.), zinc alloy plated materials (such as alloyed hot-dip galvanized, Zn-Al alloy plated, Zn-Al-Mg alloy plated, electroplated zinc alloy, etc.), aluminum plated materials, etc.; aluminum materials or aluminum alloy materials (such as 1000 series, 2000 series, 3000 series, 4000 series, 5000 series, 6000 series, aluminum castings, aluminum alloy castings, die-casting materials, etc.); magnesium materials or magnesium alloy materials; zinc materials, such as pure zinc materials and zinc alloy materials; tin materials, such as pure tin materials and tin alloy materials; lead materials, such as pure lead materials and lead alloy materials.

[0061] The metal material having a chemical conversion film can be manufactured by the above-mentioned method for manufacturing a metal material having a chemical conversion film. Examples of the chemical conversion film include zirconium chemical conversion films, titanium chemical conversion films, hafnium chemical conversion films, and vanadium chemical conversion films. The chemical conversion film may be a single layer or may be two or more layers. Here, when a zirconium chemical conversion film, a titanium chemical conversion film, a hafnium chemical conversion film, and / or a vanadium chemical conversion film are formed, the mass of the formed chemical conversion film relative to the unit area of ​​the metal material surface, calculated as the mass of zirconium, titanium, hafnium, or vanadium in the chemical conversion film, is preferably 5 mg / m 2 More than 500 mg / m 2 Less than 10 mg / m 2 More than 250 mg / m 2 When two or more metals are contained, the total amount thereof is preferably within the above range.

[0062] The amount of zirconium, titanium, hafnium, or vanadium in chemical conversion films such as zirconium, titanium, hafnium, and vanadium can be measured by dissolving the chemical conversion film in concentrated nitric acid and then performing ICP emission spectrometry. Alternatively, the amount of zirconium, titanium, hafnium, or vanadium in the chemical conversion film can be measured by analyzing the metal material having the chemical conversion film using X-ray fluorescence.

[0063] The coated metal material can be manufactured by the above-mentioned method for manufacturing the coated metal material. Here, the coating film formed on the coated metal material can be a single layer or a multilayer. In the case of a multilayer, the coating materials, coating methods, drying methods, etc. of the various layers can be the same or different. In addition, the coating film can be a thick coating film with a thickness exceeding 100 μm, or a thin coating film with a thickness less than 5 μm. For example, in the case of electrophoretic coating, the thickness of the coating film is generally about 10 to 30 μm, but it can also be as thick as 100 μm or as thin as 3 μm.

[0064] Example

[0065] Hereinafter, the effects of the present invention will be described in detail with reference to Examples, but the present invention is not limited to the following Examples.

[0066] Preparation of post-treatment agents after chemical conversion

[0067] As shown in Table 1, chemical conversion post-treatment agents 1 to 33 were prepared by adding water to achieve a predetermined molar concentration of the source of the compound or polymer (A) and the metal acid ion (B). In the preparation of the chemical conversion post-treatment agents, the following A1 to A15 and B1 to B4 were used as the source of the compound or polymer (A) and the metal acid ion (B). The pH of the chemical conversion post-treatment agent was 10.

[0068] A1; Ethylenediamine Tokyo Chemical Industry Co., Ltd.

[0069] A2; Diethylenetriamine Tokyo Chemical Industry Co., Ltd. A3; Triethylenetetramine Tokyo Chemical Industry Co., Ltd. A4; Tetraethylenepentamine Tokyo Chemical Industry Co., Ltd. A5; Pentaethylenehexamine Tokyo Chemical Industry Co., Ltd. A6; Epomin (registered trademark) SP-200 Nippon Shokubai Co., Ltd. A7; 1,3-Diaminopentane Tokyo Chemical Industry Co., Ltd. A8; 2-Methyl-1,3-propanediamine Tokyo Chemical Industry Co., Ltd. A9; 3,3'-Diamino-N-methyldipropylamine Tokyo Chemical Industry Co., Ltd. A10; Tris(3-aminopropyl)amine Tokyo Chemical Industry Co., Ltd. A11; 1,3-Diamino-2-propanol Tokyo Chemical Industry Co., Ltd. A12; PAA-01 Nittobo Medical Co., Ltd. A13; PAS-410C Nittobo Medical CO., LTD. A14; SUPERFLEX620 Dai-ichi Kogyo Seiyaku Co., Ltd. A15; PAS-21CL NITTOBO MEDICAL CO., LTD. B1; Sodium molybdate dihydrate Junsei Chemical Co., Ltd. B2; Ammonium molybdate (tetrahydrate) Kishida Chemical Co., Ltd. B3; Sodium tungstate dihydrate NACALAI TESQUE, INC. B4; Ammonium paratungstate Nippon Inorganic Chemical Industry Co., Ltd.

[0070] [Table 1]

[0071]

[0072] [Production of painted metal materials]

[0073] <Metal Materials>

[0074] As metal materials, cold-rolled mild steel sheets (SPCC: 0.8 mm thick) specified in JIS G3141:2011, hot-dip galvanized steel sheets (SGCC: 0.8 mm thick) specified in JIS G3302:2012, alloyed hot-dip galvanized steel sheets (SCGA: 0.8 mm thick) specified in JIS G3302:2012, and aluminum alloy sheets (A6061: 0.8 mm thick) specified in JIS H4000:2014 were prepared and cut into 70 mm wide x 150 mm long dimensions. In the evaluation of the coated metal materials described below, the surface with burrs generated on the edges of the metal materials was used as the evaluation surface. The height of the burrs generated was approximately 100 μm.

[0075] <Degreasing of Metal Materials>

[0076] Various metal materials were immersed in an alkaline degreasing agent (an aqueous solution of Fine Cleaner E2093 (Nihon Parkerizing Co., Ltd.) mixed in water at a concentration of 13 g / L of Agent A and 11 g / L of Agent B) at 45°C for 2 minutes to remove oil and dirt from the surfaces of the metal materials. The surfaces of the metal materials were then rinsed with water.

[0077] <Chemical conversion treatment>

[0078] The various metal materials subjected to the above degreasing treatment were immersed in a 50 g / L aqueous solution of a zirconium chemical conversion treatment agent (Pallucid 1500, manufactured by Nihon Parkerizing Co., Ltd.) at 40° C. for 120 seconds to prepare metal materials having a zirconium chemical conversion film formed thereon.

[0079] In addition, in Example 36, 100 mg / L of KBM-603 (Shin-Etsu Chemical Co., Ltd.) was added to a 50 g / L aqueous solution of a zirconium chemical conversion treatment agent (Pallucid 1500, manufactured by Nihon Parkerizing Co., Ltd.) to obtain an aqueous solution, and a degreased metal material (SCGA) was immersed in the above aqueous solution at 40°C for 120 seconds to produce a metal material having a zirconium chemical conversion film formed thereon.

[0080] In addition, in Example 37, 10 mg / L of copper sulfate (II) pentahydrate (NACALAITESQUE, INC.) was added in terms of copper to a 50 g / L aqueous solution of a zirconium chemical conversion treatment agent (Pallucid 1500, manufactured by Nihon Parkerizing Co., Ltd.) to obtain an aqueous solution, and a degreased metal material (SCGA) was immersed in the above aqueous solution at 40°C for 120 seconds to produce a metal material having a zirconium chemical conversion film formed thereon.

[0081] <Post-processing of metal materials>

[0082] The various metal materials (Examples 1 to 37 and Comparative Example 2) subjected to the above-mentioned chemical conversion treatment were immersed in various chemical conversion post-treatment agents shown in Table 2 at 25° C. for 90 seconds to perform post-treatment.

[0083] <Electrophoretic coating of metal materials>

[0084] After the metal material on which the zirconium chemical conversion film was formed was washed with pure water, various metal materials were used as cathodes, and cationic electrophoretic paint (GT-100, manufactured by Kansai Paint Co., Ltd.) was used to perform electrolysis for 180 seconds at a voltage set to 200V to precipitate the coating components on the entire surface of the metal material. Then, the metal material was washed with pure water and sintered at 170°C (PMT: the highest temperature of the metal material during sintering) for 20 minutes to produce a coated metal material. In addition, the coating thickness of the coated metal material was adjusted to 20μm. The coated metal materials produced at this time are shown in Tables 2 and 3 as Examples 1 to 37 and Comparative Examples 1 and 2. In addition, in Comparative Example 1, no post-chemical conversion treatment was implemented.

[0085] [Table 2]

[0086]

[0087] [Table 3]

[0088] Comparative Example Metal materials Chemical conversion treatment agents Chemical conversion post-treatment agent 1 SCGA PLC-1500 - 2 SCGA PLC-1500 33

[0089] <Corrosion Resistance Evaluation>

[0090] In order to confirm the corrosion resistance of the burr portion of the edge of each coated metal material of Examples 1 to 37 and Comparative Examples 1 and 2 prepared above, each coated metal material was placed in a composite cycle tester, and a composite cycle test of 100 cycles was performed in accordance with JASO-M609-91. After 100 cycles, the maximum expansion amplitude of the burr generated during cutting was measured, and the corrosion resistance of the burr portion of the edge was evaluated according to the evaluation criteria shown below. In addition, since the burr on the edge was evaluated, the edges and backs of the various coated metal materials were not sealed with tape. The results are shown in Tables 4 and 5. In addition, the evaluation criteria B and above are used as the practical range.

[0091] (Evaluation Criteria)

[0092] S: Maximum expansion is less than 1.0 mm. (Excellent)

[0093] A: The maximum expansion range is 1.5mm or more and less than 2.5mm.

[0094] B: The maximum expansion amplitude is 2.5 mm or more and less than 5.0 mm.

[0095] C: The maximum expansion amplitude is 5.0 mm or more.

[0096] [Table 4]

[0097] Example Corrosion resistance evaluation 1 B 2 B 3 B 4 B 5 B 6 B 7 B 8 B 9 B 10 B 11 B 12 B 13 B 14 B 15 B 16 B 17 A 18 S 19 S 20 S 21 B 22 A 23 S 24 S 25 S 26 S 27 A 28 A 29 S 30 S 31 A 32 A 33 A 34 B 35 S 36 A 37 A

[0098] [Table 5]

[0099] Comparative Example Corrosion resistance evaluation 1 C 2 C

[0100] Furthermore, while the present invention has been described in detail with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the present invention.

Claims

1. A coated metal material having a coating film, the coating being obtained by bringing a treatment agent into contact with the chemical conversion film of a metal material having a chemical conversion film and then coating the metal material. The chemical conversion film is formed by any one chemical conversion treatment selected from zirconium chemical conversion treatment, titanium chemical conversion treatment, hafnium chemical conversion treatment, and vanadium chemical conversion treatment, The treating agent comprises a water-soluble or water-dispersible compound or polymer (A), wherein the compound or polymer (A) is selected from one or more of a compound or polymer having -NH2, a compound or polymer having -NH2 and -NH-, and a compound or polymer having -NH-.

2. The coated metal material having a coating film according to claim 1, wherein The pH of the treatment agent is 7.0 or higher and 14.0 or lower.

3. The coated metal material having a coating film according to claim 1, wherein The pH of the treatment agent is 9.0 or higher and 14.0 or lower.

4. The coated metal material having a coating film according to claim 1, wherein It further contains at least one metal acid ion (B) selected from molybdate ions and / or tungstate ions.

5. A method for producing a coated metal material having a coating film, comprising: a step of forming a chemical conversion film on the surface of the metal material or on the surface thereof by any one chemical conversion treatment selected from zirconium chemical conversion treatment, titanium chemical conversion treatment, hafnium chemical conversion treatment, and vanadium chemical conversion treatment, a post-chemical conversion treatment step of bringing a treatment agent into contact with the chemical conversion film, and a coating step of coating the surface of the metal material having the chemical conversion film after the chemical conversion post-treatment step; The treating agent comprises a water-soluble or water-dispersible compound or polymer (A), wherein the compound or polymer (A) is selected from one or more of a compound or polymer having -NH2, a compound or polymer having -NH2 and -NH-, and a compound or polymer having -NH-.

6. The method for producing a coated metal material having a coating film according to claim 5, wherein: The pH of the treatment agent is 7.0 or higher and 14.0 or lower.

7. The method for producing a coated metal material having a coating film according to claim 5, wherein: The pH of the treatment agent is 9.0 or higher and 14.0 or lower.

8. The method for producing a coated metal material having a coating film according to claim 5, wherein: The coating process includes a process of performing cationic electrophoretic coating.

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