METAL SURFACE TREATMENT AGENT, AND METAL MATERIAL WITH COATING FILM AND METHOD FOR MANUFACTURING THE SAME

Abstract

The present invention addresses the problem of providing: a metal surface treatment agent capable of forming a film having excellent corrosion resistance and excellent hydrophilicity on or above a metal surface; a method for producing a metal material having a film by using the metal surface treatment agent; and a metal material having a film, obtained by the method. A chemical agent, containing prescribed amounts of water-soluble or water-dispersible resin (A) and a compound (B) having a nitrile group and an amino group, is capable of forming a film having excellent corrosion resistance and excellent hydrophilicity on or above a metal surface and can therefore solve the problem described above.

Description

METAL SURFACE TREATMENT AGENT, AND FILM-COATED METAL MATERIAL AND METHOD FOR MANUFACTURING HIMSELF TECHNICAL FIELD The present invention relates to: a metal surface treatment agent; a method for producing a metal material having a film by using the metal surface treatment agent; and a metal material having a film, obtained by the method. PRIOR ART Metal surface treatment agents have been developed for forming a film with excellent corrosion resistance on a metal material. For example, Patent Document 1 proposes an aqueous solution containing a specific amphoteric polymer and a crosslinking agent containing a water-soluble chromium compound. Patent Document 2 proposes a resin-containing liquid with a pH of 1.5 to 3.0, containing prescribed amounts of a specific carboxyl-containing resin, a vinyl monomer, and a persulfate ion or hydrogen peroxide. RELATED TECHNICAL DOCUMENTS PATENT DOCUMENTS [Patent Document 1] Publication of Japanese Unexamined Patent Application No. H8-206594 czronn / zznz / E / Y [Patent Document 2] Japanese Unexamined Patent Application Publication No. S54-142253 BRIEF DESCRIPTION OF THE INVENTION PROBLEMS SOLVED BY THE INVENTION However, a film formed by the aqueous solution described in Patent Document 1 does not have sufficient corrosion resistance and is required to have superior performance. Furthermore, a film formed by the resin-containing liquid described in Patent Document 2 does not have sufficient hydrophilicity and is required to have superior performance. In view of this, an objective of the present invention is to provide: a metal surface treatment agent that can form a film having excellent corrosion resistance and excellent hydrophilicity on or above a metal surface; a method for producing a metal material having a film by using the metal surface treatment agent; and a metal material having a film, obtained by the method. MEANS TO SOLVE PROBLEMS The present inventors intensively studied how to solve the problems described above and consequently discovered that a film having excellent corrosion resistance and excellent hydrophilicity can be formed on or over a surface of a metal material by using a chemical agent containing a water-soluble or water-dispersible resin and a compound having a nitrile group and an amino group, thereby completing the present invention. In other words, the present invention covers the following. [ 1] A metal surface treatment agent, containing: a water-soluble or water-dispersible resin (A); and a compound (B) having a nitrile group and an amino group. [2] The metal surface treatment agent according to [1] wherein a ratio [Bm / Am] between the mass (Am) of the resin (A) and the mass (BM) of the compound (B) is in the range of 0.03 to 1.50. [3] The metal surface treatment agent according to [1] or [2], wherein the resin (A) is a resin containing at least one functional group selected from an amino group, an amide group, a carboxy group, and a hydroxy group. [4] The metal surface treatment agent according to any of [1] to [3], wherein compound (B) has a molecular weight of 1,000 or less. [5] The metal surface treatment agent according to any of [1] to [4], further containing by czronn / zznz / E / Y czronn / zznz / E / Y at least one inorganic compound (C) selected from a chromium compound, a vanadium compound, a titanium compound and a zirconium compound, wherein a ratio [Bm / Cm] between the mass (BM) of compound (B) and the mass (CM) of inorganic compound (C) is in the range of 0.10 to 5.00. [6] A method for producing a metal material having a film, the method including the steps of: carry the metal surface treatment agent in accordance with any of [1] to [5] in contact with or on a surface of a metal material; and dry the metal surface treatment agent thus carried in contact with or on the surface of the metal material. [7] A metal material having a film, which is obtained by the method according to [6]. EFFECTS OF THE INVENTION According to the present invention, the following can be provided: a metal surface treatment agent that can form a film having excellent corrosion resistance and excellent hydrophilicity on or over a surface of a metal material; a method for producing a metal material having a film by using the metal surface treatment agent; and a metal material having a film, which is obtained by the method. METHOD FOR CARRYING OUT THE INVENTION The metal surface treatment agent according to the present embodiment, a method for producing a metal material having a film by using the metal surface treatment agent, and a metal material having a film, obtained by the method, will now be described. (Metal Surface Treatment Agent) The metal surface treatment agent according to the present embodiment comprises: a resin (A); and a compound (B) having a nitrile group and an amino group (hereinafter simply referred to as compound (B)). By using this metal surface treatment agent, a film having excellent corrosion resistance and excellent hydrophilicity can be formed on or over a metal surface.<Resina (A)> The resin (A) is not particularly limited as long as it is a water-soluble or water-dispersible resin, and examples thereof include urethane resins, polyvinyl alcohol resins, polyamide resins, epoxy resins, acrylic resins, amine resins, phenolic resins, and polyvinylpyrrolidone resins. The resin (A) may be a homopolymer of a urethane resin, a polyvinyl alcohol resin, a polyamide resin, an epoxy resin, a phenolic resin, a polyvinylpyrrolidone resin, or the like; a modification product obtained by modifying a side chain of the homopolymer with another compound; or a copolymer of a combination of two or more of the resins described above and the modification product.Among these, it is particularly preferred to use a resin that has a functional group such as an amino group, an amide group, a carboxy group, or a hydroxy group, more specifically a resin that has a functional group directly bonded to a carbon atom. Furthermore, the weight-average molecular weight of the resin (A) is not particularly limited as long as it is not less than 2,000, and the weight-average molecular weight of the resin (A) is preferably not less than 4,000, and more preferably not less than 10,000. An upper limit for the same is preferably 1,000,000 or less. The resin (A) may contain any one, two, or more of the groups described above. Additionally, the metal surface treatment agent may be produced by blending any one, two, or more of the resins described above. <Compuesto (B)> Compound (B) is not particularly limited as long as it is a compound having a nitrile group and an amino group and is different from resin (A), and examples of compound (B) include cyanamide, aminoacetonitrile, 3-aminopropionitrile, dicyandiamide, 3-aminocrotononitrile, 2-amino-1,1,3-tricyan-1-propene, 2-aminobenzonitrile, 3-aminobenzonitrile, 4-aminobenzonitrile, 2-aminobenzyl cyanide, 4-aminobenzyl cyanide, 2-amino-β-bromobenzonitrile, 2-amino-β-nitrobenzonitrile, 4-amino-3-bromobenzonitrile, 2-amino-4-chlorobenzonitrile, 2-amino-5-chlorobenzonitrile, 2-amino-4,5-dicyan-1H-imidazole, and 4-(aminomethyl)benzonitrile. The molecular weight of compound (B) is preferably 1,000 or less, more preferably 800 or less, particularly preferably 500 or less. In addition, it is preferred that compound (B) not be a polymer having a repeating structure. In the metal surface treatment agent for the present embodiment, the content ratio of the resin (A) to the compound (B) is not particularly limited; however, a [BM / AM] ratio between the mass (AM) of the resin (A) and the mass (BM) of the compound (B) is preferably in the range of 0.03 to 1.50, more preferably in the range of 0.10 to 1.00, particularly preferably in the range of 0.10 to 0.50. When the metal surface treatment agent contains two or more classes of the resins (A) and / or two or more classes of the compounds (B), a [Bm / Am] ratio calculated using a total mass of the respective components is preferably in the range described above. czronn / zznz / E / Y<Otros Componentes> The metal surface treatment agent according to this embodiment may consist solely of the resin (A) and the compound (B) in addition to an aqueous medium, or it may contain other components. Examples of other components include an inorganic compound (C) and a surfactant. Furthermore, the metal surface treatment agent according to this embodiment may or may not contain hydrogen peroxide or a persulfate. The inorganic compound (C) is, for example, a chromium compound, a vanadium compound, a titanium compound, or a zirconium compound. The chromium compound is not specifically limited as long as it contains elemental chromium, and examples include chromium sulfate, chromium nitrate, chromium bisphosphate, chromium fluoride, chromium acetate, chromium formate, chromic anhydride, and bichromatic acid. The vanadium compound is not specifically limited as long as it contains elemental vanadium, and examples include vanadium pentoxide, ammonium metavanadate, sodium metavanadate, vanadium oxytrichloride, vanadium trioxide, vanadium dioxide, vanadium oxysulfate, vanadium oxyacetylacetonate, vanadium acetylacetonate, vanadyl acetylacetonate, vanadium trichloride, phosphovanadomolybdic acid, and vanadium sulfate.The titanium compound is not limited to czronn / zznz / E / Y particularly as long as it is a compound containing elemental titanium, and examples thereof include titanyl sulfate, titanyl nitrate, titanium nitrate, titanyl chloride, titania sol, titanium oxide, titanium potassium oxalate, titanium iactate, titanium tetraisopropoxide, titanium acetylacetonate, diisopropyl titanium bis-acetylacetone, and fluorotitanic acid and salts thereof, as well as metatitanic acid obtained by thermal hydrolysis of an aqueous titanyl sulfate solution, orthotitanic acid obtained by alkaline neutralization of an aqueous titanyl sulfate solution, and salts of these acids.The term "zirconium compound" is not particularly limited as long as it is a compound containing elemental zirconium. Examples include zirconium nitrate, zirconium oxynitrate, zirconyl acetate, zirconyl sulfate, zirconyl ammonium carbonate, zirconyl potassium carbonate, zirconyl sodium carbonate, zirconia sol, and fluorozirconic acid and its salts, as well as zirconic acid obtained by ion exchange or alkaline neutralization of an aqueous solution of a water-soluble zirconium salt, and zirconic acid salts. The metal surface treatment agent may contain any one, two, or more of these inorganic compounds. When the metal surface treatment agent according to the present embodiment contains the inorganic compound (C), the content ratio of compound (B) to inorganic compound (C) in the metal surface treatment agent is not particularly limited; however, a ratio [Bm / Cm] between the mass (Bm) of compound (B) and the mass (Cm) of inorganic compound (C) is preferably in the range of 0.10 to 5.00, more preferably in the range of 0.20 to 4.00, particularly preferably in the range of 0.30 to 3.00. When the metal surface treatment agent contains two or more classes of compounds (B) and / or two or more classes of inorganic compounds (C), a ratio [Bm / Cm] calculated using a total mass of the respective components is preferably in the range described above. Like the surfactant, a cationic, anionic, amphoteric, or non-ionic surfactant can be used, and examples of these include: cationic surfactants, such as alkylamine salts and alkyltrimethyl ammonium halides; anionic surfactants, such as alkyl sulfonates, polyoxyethylene alkylphenyl ether sulfates, sodium dodecyldiphenyl ether disulfonate, and sodium dodecyl sulfate; amphoteric surfactants, such as alkyl aminopropionates and alkyldimethyl betaines; and non-ionic surfactants, such as polyoxyethylene alkylphenyl ethers, polyoxyalkylene fatty acid esters, fatty acid glycerol esters, sorbitan fatty acid esters, polyoxyethylene glycerol fatty acids, and polyoxyethylene propylene glycol fatty acid esters. These surfactants can be used individually, or in combination with two or more of them.<Medio Acuoso> The aqueous medium is not particularly limited as long as it contains water in an amount of not less than 50% by mass, and the aqueous medium may consist solely of water, or it may be a mixture containing water and a water-miscible organic solvent. The water-miscible organic solvent is not particularly limited as long as it is miscible with water, and examples include: cetone-based solvents, such as acetone and methyl ethyl ketone; amide-based solvents, such as N,N'-dimethylformamide and dimethylacetamide; alcohol-based solvents, such as methanol, ethanol, and isopropanol; ether-based solvents, such as ethylene glycol monobutyl ether and ethylene glycol monohexyl ether; and pyrrolidone-based solvents, such as 1-methyl-2-pyrrolidone and 1-ethyl-2-pyrrolidone. These water-miscible organic solvents can be mixed with water individually, or two or more of them can be mixed with water.(Method for Producing the Metal Surface Treatment Agent). The metal surface treatment agent according to the present embodiment can be produced, for example, by mixing prescribed quantities of the resin (A), the compound (B) and, as referred to, other component(s) in an aqueous medium. (Metal Material that has a Film and Production Method on It) The method for producing a metal material having a film according to the present embodiment (hereinafter referred to simply as the production method according to the present embodiment) includes: the contact step of bringing the metal surface treatment agent described above into contact with or on a metal surface; and the drying step of drying the metal surface treatment agent thus brought into contact with or on the metal surface. By this production method, a metal material having a film that has excellent corrosion resistance and excellent hydrophilicity on or on the surface can be obtained. In the production method according to the present embodiment, the degreasing step and / or the chemical conversion treatment step can be performed before the contact step.<Material de Metal> The shape, structure, and similar characteristics of the metal material on which a film is to be formed are not particularly limited, and the metal material may be in the form of, for example, a plate or a thin sheet. The type of metal material is also not particularly limited, and examples include: steel materials (for example, cold-rolled steel sheets and hot-rolled steel sheets);plated materials, such as zinc-plated materials (e.g., electrogalvanized materials, hot-dip galvanized materials, galvanized materials containing aluminum, electrogalvanized materials, zinc-nickel plated materials, zinc-cobalt plated materials, and zinc vapor-deposited materials), zinc alloy plated materials (e.g., alloyed hot-dip galvanized materials, Zn-Al alloy plated materials, Zn-Al-Mg alloy plated materials, and zinc alloy electroplated materials), aluminum plated materials, nickel plated materials, tin plated materials, chromium plated materials, and chromium alloy plated materials (e.g., Cr-Ni alloy plated materials);Aluminum materials and aluminum alloy materials (e.g., 1000 series, 2000 series, 3000 series, 4000 series, 5000 series, 6000 series, aluminum castings, aluminum alloy castings, and die-casting materials); copper materials and copper alloy materials; titanium materials and titanium alloy materials; and magnesium materials and magnesium alloy materials. <Etapa de Contacto; Examples of contact methods include, but are not limited to: spraying, dipping, roller coating, stick coating, curtain coating, spin coating, and combinations thereof. The contact temperature and contact time are adjusted as appropriate according to the formulation and concentration of the metal surface treatment agent. The contact temperature and contact time are usually, but not limited to: within a range of 10°C to 45°C and within a range of 5 seconds to 600 seconds, respectively. <Etapa de Secado A drying method is not particularly limited, and examples include drying methods using known drying equipment, such as a batch-type drying oven, a continuous hot air circulation-type drying oven, a conveyor-type hot air drying oven, or an electromagnetic induction heating oven using an IH heater. The drying temperature and drying time are adjusted as appropriate according to the type of metal material and the formulation or quantity of the metal surface treatment agent brought into contact with the metal material. The drying temperature is not particularly limited; however, usually, the peak metal temperature (PMT) of the metal material is preferably in the range of 100°C to 200°C, more preferably in the range of 130°C to 170°C.The drying time is also not particularly limited; however, it is in a range of 2 seconds to 1,800 seconds.<Etapa Desengrasante> . As a degreasing method, any method may be employed as long as it removes oils, grease, and dirt adhering to the surface of the metal material. Examples of such methods include solvent degreasing and methods using an alkali-based or acid-based degreasing agent, or similar substances. In cases where the contact stage or chemical conversion treatment stage is performed after the degreasing stage, the water washing stage may or may not be performed on the surface of the metal material after the degreasing stage but before the contact stage or chemical conversion treatment stage. When the water washing stage is performed, drying may or may not be subsequently performed on the surface of the metal material. <Etapa de Tratamiento de Conversión Quimica> czronn / zznz / E / Y czronn / zznz / E / Y The chemical conversion treatment stage is not particularly limited as long as it is a treatment to form a chemical conversion coating, and examples include the zirconium chemical conversion treatment stage, the titanium chemical conversion treatment stage, the hafnium chemical conversion treatment stage, the phosphate chemical conversion treatment stage, and the chromate chemical conversion treatment stage. The water washing stage may or may not be performed on or about the surface of the metal material after the chemical conversion treatment stage but before the contact stage. When the water washing stage is performed, drying may or may not be subsequently performed on or about the surface of the metal material.In cases where the chemical phosphate conversion treatment stage using zinc phosphate is performed as the chemical conversion treatment stage, a surface finishing treatment stage can be carried out on the metal material between the degreasing stage and the chemical phosphate conversion stage to improve the reactivity of the chemical phosphate conversion treatment. Any known method can be employed as a surface finishing method for this stage. The chemical conversion treatment stage is carried out by bringing a chemical conversion agent into contact with or onto the surface of the metal material. Examples of chemical conversion agents include, but are not limited to: zirconium chemical conversion agents, titanium chemical conversion agents, hafnium chemical conversion agents, phosphate chemical conversion agents, and chromate chemical conversion agents. Examples of methods for bringing the chemical conversion agent into contact include, but are not limited to: known contact methods such as a dip treatment method, a spray treatment method, a pouring method, and a combination of these methods.In the various stages of chemical conversion treatment described above, the temperature and contact time of the chemical conversion agent can be adjusted as appropriate according to the type of chemical conversion treatment stage as well as the concentration and the like of the chemical conversion agent.<Película> . The amount of adhesion of the film formed by the metal surface treatment agent on or to the surface of the metal material is not particularly limited, provided the performance of the present invention can be achieved; however, for example, preferably in the range of 0.05 g / m² to 1.5 g / m², and more preferably in the range of 0.1 g / m² to 1.0 g / m². It is mentioned herein that, between the metal material and the film, a chemical conversion coating obtained by the chemical conversion treatment step described above may also be provided. EXAMPLES The present invention will now be described in more detail by means of Examples and Comparative Examples. It is mentioned here, however, that the present invention is not limited to the Examples described below. (Preparation of Metal Surface Treatment Agents) A water-soluble or water-dispersible resin, a nitrile compound, and an inorganic compound in the respective prescribed amounts shown in Table 1 were added to deionized water in the order listed, and a surfactant (ADERA PLURONIC L-61, manufactured by ADERA Corporation) was further added to a final concentration of 10 g / L. Subsequently, deionized water was further added to the resulting material such that the total mass of the water-soluble or water-dispersible resin, the nitrile compound, the inorganic compound, and the surfactant was 100 g / L, thereby producing the metal surface treatment agents of Examples 1 to 11 and Comparative Examples 1 to 5. The components represented by the respective symbols in the Type columns in Table 1 are listed below. [Table 1] czronn / zznz / E / Y Table 1 czronn / zznz / E / Y Water-soluble or Water-dispersible resin Nitrile compound Inorganic compound Classes Parts by Mass Classes Parts by Mass Bm / Am Classes Parts by Mass Bm / Cm Example 1 Al 30 B1 10 0.33 Example 2 A2 30 B1 10 0.33 Example 3 A3 30 B1 10 0.33 Example 4 Al 30 B2 10 0.33 Example 5 Al 30 B1 4 0.13 C1 7.1 0.56 Example 6 Al 30 B1 4 0.13 C2 7.1 0.56 Example 7 Al 40 B1 2 0.05 C1 6.1 0.33 Example 8 Al 30 B1 10 0.33 C1 5 2.00 Example 9 Al 20 B1 20 1.00 E j Example 10 Al 30 B1 45 1.50 Example 11 Al 30 B1 1 0.03 Comparative Example 1 Al 30 0.00 Comparative Example 2 B1 30 Comparative Example 3 B1 10 C1 7.1 0.56 Comparative Example 4 Al 30 B3 10 0.33 Comparative Example 5 Al 30 B4 10 0.33 <Resinas Solubles en Agua o Dispersadles en Agua> Al: polyvinyl alcohol (KURARAY POVAL PVA-103, czronn / zznz / E / Y manufactured by Kuraray Co., Ltd.) A2: polyacrylic acid (AQUALIC DL-40S, manufactured by Nippon Shokubai Co., Ltd.) A3: Polyacrylamide (POLYSTRON 387-20, manufactured by Arakawa Chemical Industries, Ltd.) Nitrile Compounds> B1: dicyandiamide (dicyandiamide, manufactured by Nippon Carbide Industries Co., Ltd.) B2: aminopropionitrile (manufactured by Tokyo Chemical Industry Co., Ltd.) B3: propionitrile (propanenitrile, manufactured by Yoneyama Yakuhin Kogyo Co., Ltd.) B4: acrylonitrile-butadiene latex (1571C2, manufactured by Zeon Corporation) Inorganic Compounds Cl: chromium sulfate C2: vanadium oxysulfate (Preparation of Evaluation Samples Nos. 1 to 16) As test materials, aluminum sheets (1050, thickness: 0.6 mm) were each immersed in an alkali-based degreasing agent [FINE CLEANER 315E (manufactured by Nihon Parkerizing Co., Ltd.) dissolved in water at a mass concentration of 2%] at 60 °C for 2 minutes to perform a degreasing treatment. Subsequently, the surface of each test material was washed with water. The test materials, which had been degreased and washed with water, were each immersed in a zirconium-based chemical conversion agent [PALCOAT 3762 (manufactured by Nihon Parkerizing Co., Ltd.) dissolved in water at a mass concentration of 5% and adjusted to have a pH of 4.0] at 60°C for 2 minutes to perform a chemical conversion treatment. After the chemical conversion treatment, the surface of each test material was washed with water. The test materials, on which a chemical conversion coating had been formed by chemical conversion treatment, were immersed in the respective metal surface treatment agents (metal surface treatment agents of Examples 1 to 11 and Comparative Examples 1 to 5) at 25°C for 10 seconds and subsequently heat-dried at 150°C for 6 minutes using a blow dryer, thereby producing test materials having a film (evaluation samples Nos. 1 to 16). (Preparation of Evaluation Samples Nos. 17 to 32) As test materials, steel sheets coated with 55% aluminum-zinc (sheet thickness: 0.35 mm) were each immersed in an alkali-based degreasing agent [FINE CLEANER 6404 (manufactured by Nihon Parkerizing Co., czronn / zznz / E / Y czronn / zznz / E / Y Ltd.) dissolved in water at a mass concentration of 2%] at 60 °C for 30 seconds to perform a degreasing treatment. Subsequently, the surface of each test material was washed with water. The test materials, which had been degreased and washed with water in this manner, were immersed in the respective metal surface treatment agents (metal surface treatment agents of Examples 1 to 11 and Comparative Examples 1 to 5) at 25°C for 10 seconds and subsequently heat-dried at 150°C for 6 minutes using a blow dryer, thereby producing test materials having a film (evaluation samples Nos. 17 to 32). (Method for Evaluating Corrosion Resistance)<Prueba de Rocío de Sal Neutra: SST> Based on a salt spray test method (JIS Z2371:2015), the area ratio (%) of white rust generated on the surface of each evaluation sample was determined after 240 hours of salt spray, and the corrosion resistance (SST) was evaluated according to the following evaluation criteria. An evaluation result of B or better was considered satisfactory.<Prueba de Rocío de Sal de Acido acético: AASST> Based on a salt spray test method (JIS Z2371:2015), the area ratio (%) of white rust generated on the surface of each evaluation sample was determined after 240 hours of spraying with an aqueous solution, which was prepared by adjusting the pH of a salt solution containing copper(II) chloride with acetic acid to 3.0, and the corrosion resistance (AASST) was evaluated according to the following evaluation criteria. Evaluation Criteria> A: The area ratio was less than 10%. B: The area ratio was 10% or higher but less than 20%. C: The area ratio was 20% or higher. (Method for Evaluating Initial Hydrophilicity) A drop of water was placed on the surface of each evaluation sample, and the contact angle was immediately measured using a contact angle meter to assess the initial hydrophilicity according to the following evaluation criteria. Evaluation Criteria> A: The contact angle was less than 10°. B: The contact angle was 10° or larger but smaller than 30°. C: The contact angle was 30° or greater. (Method for Evaluating Durable Hydrophilicity) After drying the surface of each evaluation sample submerged in water for 96 hours, a drop of czronn / zznz / E / Y water was dropped onto it, and the contact angle immediately afterwards was measured using a contact angle meter to evaluate durable hydrophilicity according to the following evaluation criteria.<Criterios de Evaiuación> A: The contact angle was smaller than 20°. B: The contact angle was 20° or larger but smaller than 40°. C: The contact angle was 40° or greater. (Method for Evaluating Adhesion) The surface of each evaluation sample was rubbed reciprocally with a water-moistened gauze while pressing the gauze against the surface with a 500 g load. The number of reciprocal rubbings that caused detachment was measured, and the initial adhesion was evaluated according to the following evaluation criteria. Furthermore, after the surface of each evaluation sample had been dried by immersion in water for 96 hours, a prescribed area of ​​the surface was rubbed reciprocally with a water-moistened gauze while pressing the gauze against the surface with a 500 g load. The number of reciprocal rubbings that caused detachment was measured, and the durable adhesion was evaluated according to the following evaluation criteria.<Criterios de Evaluación> A: The reciprocity number was 20 or higher. czronn / zznz / E / Y B: The reciprocity number was 10 or more but less than 20. C: The reciprocation number was less than 10. (Method for Evaluating Water Resistance) After drying the surface of each evaluation sample submerged in water for 96 hours, the mass (Em) of the evaluation sample was measured, and the rate of change with respect to the mass (Sm) before immersion in water, [ (1 Em / Sm) x 100], was calculated to evaluate water resistance according to the following evaluation criteria.<Criterios de Evaluación> A: The rate of change was 10% or less. B: The rate of change was higher than 10% but 25% or less. C: The rate of change was higher than 25%. (Fade Resistance) Based on a salt spray test method (JIS Z2371:2015), the area ratio (%) of black discoloration that occurred on the surface of each evaluation sample after 72 hours of spraying with neutral salt water was determined, and resistance to discoloration was evaluated according to the following evaluation criteria. An evaluation result of B or better was considered satisfactory. Evaluation Criteria> czronn / zznz / E / Y A: The area ratio was 10% or less. B: The area ratio was higher than 10% but 30% or less. C: The area ratio was higher than 30%. Tables 2 and 3 show the results of evaluating corrosion resistance, hydrophilicity, adhesion, water resistance, and discoloration resistance for each evaluation sample. An evaluation result of B or better was considered satisfactory. [Table 2] Table 2 Metal Surface Treatment Agent Sample Corrosion Resistance Hydrophilicity Adhesion Water Resistance Discoloration Resistance SST AASST Initial Durable Initial Durable Evaluation No. 1 Example 1 ABAAABAB No. 2 Example 2 ABAAABAB No. 3 Example 3 ABAAABAB No. 4 Example 4 ABAAABAB No. 5 Example 5 AAAAAAAA No. 6 Example 6 AAAAAAAA No. 7 Example 7 AAAAAAAA No. 8 Example 8 AAAAAAAA No. 9 Example 9 ABAAABAB No. 10 Example 10 BBAABBBB No. 11 Example 11 BBBBABAB No. 12 Comparative Example 1 cc BBA c B c czronn / zznz / E / γ No . 13 Comparative Example 2 cc B ccccc No . 14 Comparative Example 3 B c B c BBB c No . 15 Comparative Example 4 ABB c ABB c No . 16 Comparative Example 5 ABC c AAA c [Table 3] Table 3 Metal Surface Treatment Agent Evaluation Sample Corrosion Resistance Hydrophilicity Adhesion Water Resistance Discoloration Resistance SST Initial Durable Initial Durable No. 17 Example 1 AAAABAB No. 18 Example 2 AAAABAB No. 19 Example 3 AAAABAB No. 20 Example 4 AAAABAB No. 21 Example 5 AAAAAAA No. 22 Example 6 AAAAAAA No. 23 Example 7 AAAAAAA No. 24 Example 8 AAAAAAA No. 25 Example 9 AAAABAB No. 26 Example 10 BAABBBB No. 27 Example 11 BAABBBB No. 28 Comparative Example 1 c BBA c B c No. 29 Comparative Example 2 c B ccccc czronn / zznz / E / Y No. 30 Comparative Example 3 CBBA c BC No. 31 Comparative Example 4 CBCCCBC No. 32 Comparative Example 5 A cc AAA c The present invention has been described in detail above with reference to specific examples thereof; however, it is obvious to those skilled in the art that various modifications and changes can be made without departing from the essence and scope of the present invention.

Claims

1. A metal surface treatment agent, characterized in that it comprises: a water-soluble or water-dispersible resin (A); and a compound (B) comprising a nitrile group and an amino group, wherein a ratio [Bm / Am] between the mass (Am) of the resin (A) and the mass (Bm) of the compound (B) is in the range of 0.03 to 1.

50.

2. The metal surface treatment agent according to claim 1, characterized in that the resin (A) is a resin comprising at least one functional group selected from an amino group, an amide group, a carboxy group, and a hydroxy group.

3. The metal surface treatment agent according to claim 1 or 2, characterized in that the compound (B) has a molecular weight of 1,000 or less.

4. The metal surface treatment agent according to any of claims 1 to 3, characterized in that it further comprises at least one inorganic compound (C) selected from a chromium compound, a vanadium compound, a titanium compound and a zirconium compound, wherein a ratio [BM / CM] between the mass (BM) of compound (B) and the mass (CM) of the inorganic compound (C) is in the range of 0.10 to 5.

00.

5. A method for producing a metal material comprising a film, the method characterized in that 5 comprises the steps of: bringing the metal surface treatment agent according to any of claims 1 to 4 into contact with or on a surface of a metal material; and 10 drying the metal surface treatment agent thus brought into contact with or on the surface of the metal material.

6. A metal material comprising a film, characterized in that it is obtained by the method in accordance with claim 5.