KR102130197B1 - Surface treatment agent for metal materials and metal materials - Google Patents

Abstract

An object of the present invention is to provide a metal material having a surface treatment agent for a metal material that can form a coating having corrosion resistance and excellent liquid stability, and a metal surface treatment film formed by the surface treatment agent. 1 type selected from alkali metal salt (component a) and nitrate (component b) of zirconium carbonate, urethane resin, epoxy resin, acrylic resin, phenol resin, polyester resin, polyvinyl resin, polyolefin resin and natural polymer Or the said subject is solved by the surface treatment agent for metallic materials containing 2 or more types of organic polymers (component c), pH being 7 or more and 12 or less.

Description

Surface treatment agent for metal materials and metal materials

The present invention relates to a surface treatment agent for a metal material and a metal material having a metal surface treatment film formed by the surface treatment agent.

As a surface treatment agent capable of forming a film having corrosion resistance, conventionally, ones containing zirconium ammonium carbonate have been developed (see, for example, Patent Documents 1 and 2).

Japanese Patent Publication No. Hei1-149865 Japanese Patent Publication No. 2007-204847

However, the surface treatment agent containing the above-mentioned zirconium ammonium carbonate may increase in viscosity with time, resulting in deterioration of liquid stability. Therefore, it is an object of the present invention to provide a metal material having a surface treatment agent for a metal material having excellent corrosion resistance and a metal surface treatment film formed by the surface treatment agent.

As a result of repeated examination of the inventor to solve the above problems, the present inventor blended an alkali metal salt of zirconium carbonate with a nitrate, and a surface treatment agent having a pH adjusted to 7 or more and 12 or less, with excellent liquid stability and a corrosion-resistant coating. It has been found that can form, and has led to the completion of the present invention.

That is, the present invention,

(1) A surface treatment agent for a metal material containing an alkali metal salt (component a) and a nitrate (component b) of zirconium carbonate and having a pH of 7 or more and 12 or less (but not including fluorine);

(2) further containing one or two or more organic polymers (component c) selected from urethane resins, epoxy resins, acrylic resins, phenol resins, polyester resins, polyvinyl resins, polyolefin resins and natural polymers The surface treatment agent for metal materials as described in said (1);

(3) The surface treatment agent for metal materials according to (1) or (2), wherein the pH is 7.5 or more and 12 or less;

(4) A metal material having a surface-treated film formed by contacting the surface treatment agent for a metal material according to any one of (1) to (3) above with a surface of a metal material, followed by drying;

Etc.

According to the present invention, it is possible to form a coating having corrosion resistance, and also to provide a surface treatment agent for a metal material having excellent liquid stability and a metal material having a metal surface treatment coating formed by the surface treatment agent.

Hereinafter, the surface treatment agent for metal materials according to the present invention (hereinafter simply referred to as "surface treatment agent") and the metal material will be described in detail.

The surface treatment agent according to the present invention is in the form of an aqueous solution or an aqueous dispersion when used, and the straight type used as it is and the high concentration type diluted with water when used are included in the concept of the surface treatment agent of the present invention. Hereinafter, a straight type surface treatment agent is demonstrated as an example.

The surface treatment agent contains an alkali metal salt (component a) and a nitrate (component b) of zirconium carbonate, does not contain fluorine, and is not particularly limited as long as the pH is in the range of 7 to 12 or less and is not particularly limited. And/or additives for known surface treatment agents. However, from the viewpoint of environmental measures, a surface treatment agent that does not contain chromium or vanadium is preferable. Also preferred are surface treatment agents that do not contain cobalt, cerium and silicon. In addition, in this specification and a claim, "not including" and "excluding what is included" are well-known not to exclude the trace amount, but it is preferable not to be included completely. Hereinafter, each component is demonstrated.

Component a is an alkali metal salt of zirconium carbonate. Li, Na, K, etc. are mentioned as an alkali metal in this salt, for example. The alkali metal salt of zirconium carbonate incorporated in the surface treatment agent of the present invention may be used alone, or two or more of them may be used in combination.

Subsequently, component b is nitrate. Here, examples of the counter cation of nitric acid include monovalent or divalent metal ions, alkali metal ions, and alkaline earth metal ions. Specifically, examples of component b include sodium nitrate, potassium nitrate, lithium nitrate, ammonium nitrate, nickel nitrate, zirconium nitrate, magnesium nitrate, calcium nitrate, aluminum nitrate, and the like, but are not limited thereto. In addition, one type of nitrate to be incorporated into the surface treatment agent of the present invention may be used, or two or more types may be used in combination.

The ratio [mass ratio=Mb/Ma] of the total mass (Ma) of Zr in the alkali metal salt of zirconium carbonate (component a) and the total mass (Mb) of nitrate ions in nitrate (component b) contained in the surface treatment agent is from 0.01 to It is preferably 1.60, more preferably 0.01 to 1.00, particularly preferably 0.04 to 0.94, and most preferably 0.04 to 0.7.

In addition, in the above, although the surface treatment agent containing only the said component a and component b other than a solvent was demonstrated, as mentioned above, an organic polymer may be further mix|blended, and the well-known surface treatment additive additive may be further mix|blended. It may be a mixture of an organic polymer and an additive for a known surface treatment agent.

The organic polymer (component c) is not particularly limited as long as it is a resin used to form a film, for example, urethane resin, epoxy resin, acrylic resin, phenol resin, polyester resin, polyvinyl resin, polyolefin resin, A well-known thing, such as a natural polymer, is mentioned, and it can select suitably according to the required performance. Although these organic polymers may have any one or more functional groups of anionic groups, cationic groups and nonionic groups, it is preferable that they can be stably present in the surface treatment agent of the present invention. In addition, the surface treatment agent containing a solvent and an organic polymer may be in the form of a dissolved solution, or in the form of a dispersion such as an emulsion or dispersion.

As a urethane resin, the urethane resin which is a condensation polymerization product of polyols, such as polyether polyols and polycarbonate polyols, and polyisocyanates such as aliphatic polyisocyanate compounds, alicyclic polyisocyanate compounds, and/or aromatic polyisocyanate compounds, is described above. As a part of the polyol, polyurethane and the like obtained by using a polyol having a polyoxyethylene chain such as polyethylene glycol or polypropylene glycol are mentioned. Such a polyurethane can be water-soluble or water-oxidized by increasing the introduction ratio of the above-mentioned polyoxyethylene chain. Further, the surface treatment agent according to the present invention may or may not contain a polyester polyurethane resin having a structural unit derived from a polyester polyol in the molecule.

Further, a urethane prepolymer having an isocyanato group at both ends is prepared with polyisocyanate and polyol, and a carboxylic acid having two or more hydroxyl groups or a reactive derivative thereof is reacted therewith, and having an isocyanate group at both ends. As a derivative, triethanolamine or the like is added to make an ionomer (triethanolamine salt), and the ionomer is added to water to form an emulsion or dispersion, and diamine is added as necessary to extend the chain. By doing in this way, a water-dispersible urethane resin having an anionic property can be obtained.

The carboxylic acid and reactive derivatives used in preparing the above-mentioned water-dispersible urethane resin having anionicity are used to introduce an acidic group into the urethane resin and to easily disperse the urethane resin in water. Examples of the carboxylic acid to be used include dimethylol alkanoic acids such as dimethylolpropionic acid, dimethylolbutanoic acid, dimethylolpentanoic acid, and dimethylolhexanoic acid. Moreover, as a reactive derivative, hydrolyzable ester, such as an acid anhydride, etc. are mentioned.

As an epoxy resin, a cation obtained by reacting diamines such as ethylenediamine with an epoxy compound having two or more glycidyl groups, or an epoxy compound having a bisphenol structure such as bisphenol A or bisphenol F as a unit in the skeleton, followed by cationization And amine-modified epoxy resins or other nonionic epoxy resins in which polyalkylene oxide is added to a side chain (for example, a hydroxyl group) of an epoxy compound having two or more glycidyl groups.

In addition, as the epoxy resin, a part or all of the glycidyl group in the epoxy resin having a bisphenol structure such as bisphenol A or bisphenol F as a unit in the skeleton may be a phosphoric acid-modified epoxy resin.

As an epoxy resin having a bisphenol structure such as bisphenol A or bisphenol F as a unit in a skeleton, after dehydrochlorination reaction of epichlorohydrin with bisphenol A or bisphenol F, the addition reaction of the epoxy compound and diamine obtained by the reaction What is obtained by repetition and the thing obtained by repetition of the addition reaction of the epoxy compound which has two or more, preferably two glycidyl groups, and bisphenol (A, F) are mentioned.

Examples of the epoxy compound include diglycidyl ether of bisphenol (A, F), diglycidyl ester of orthophthalic acid, diglycidyl ester of isophthalate, diglycidyl terephthalate, and diglycyl p-oxybenzoate. Dill ester, tetrahydrophthalic acid diglycidyl ester, hexahydrophthalic acid diglycidyl ester, succinic acid diglycidyl ester, adipic acid diglycidyl ester, sebacic acid diglycidyl ester, ethylene glycol diglycidyl Ether, propylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, sorbitol polyglycidyl ether, polyalkylene glycol diglycidyl ethers , Trimellitic acid triglycidyl ester, triglycidyl isocyanurate, 1,4-glycidyloxybenzene, diglycidyl propylene urea, glycerol triglycidyl ether, trimethylolethane triglycidyl ether, trimethylol And propan triglycidyl ether, pentaerythritol tetraglycidyl ether, and triglycidyl ether of glycerol alkylene oxide adducts. These may be used alone or in combination of two or more.

Examples of the acrylic resin include homopolymers or copolymers of acrylic monomers, and copolymers of acrylic monomers and addition polymerizable monomers that can be copolymerized with the acrylic monomers. If such an acrylic resin can be stably present in a surface treatment agent, its polymerization form is not particularly limited.

Examples of the acrylic monomer include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, and n-hexyl methacrylate , 2-ethylhexyl acrylate, acrylic acid, methacrylic acid, 2-hydroxyethyl acrylate, hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, hydroxypropyl methacrylate, glycidyl acrylate, And glycidyl methacrylate, sulfoethyl acrylate, and polyethylene glycol methacrylate. Maleic acid, itaconic acid, acrylamide, N-methylolacrylamide, diacetone acrylamide, styrene, acrylonitrile, vinylsulfonic acid etc. are mentioned as addition polymerizable monomer which can copolymerize with an acrylic monomer.

As the polyester resin, for example, maleic acid, fumaric acid, itaconic acid, succinic acid, glutaric acid, suberic acid, adipic acid, azelaic acid, sebacic acid, dimer acid, trimeric acid, isophthalic acid, terephthalic acid, trimellitic acid , Polybasic acids such as trimesic acid, pyromellitic acid, naphthalenedicarboxylic acid, ethylene glycol, diethylene glycol, trimethylolpropane, neopentyl glycol, 1,4-CHDM (cyclohexanedimethanol), 1,6- Polyester polyols condensed with polyols such as hexanediol; A condensation resin condensing the polybasic acid described above with a polymer polyol, polycaprolactone polyol, polycarbonate diol, polybutadiene polyol, neopentyl glycol, methyl pentadiol, or the like; And the like. In addition, a condensate of monomers such as trimellitic acid or pyromellitic acid having three or more carboxyl groups and various polyols (having unreacted carboxyl groups) is neutralized with alkali to solubilize or water-oxidize an aqueous resin, or sulfo in the polybasic acid A water-based resin obtained by solubilizing or water-oxidizing a condensate of a monomer and various polyols in which sulfonic acid groups have been introduced by reacting sulfonic acids such as phthalic acid can also be used.

Examples of the polyvinyl resin include polyvinyl acetate, partially saponified or fully saponified polyvinyl acetate, and polyvinylpyrrolidone.

The polyvinyl-based resin also includes saponified polymers obtained by copolymerizing vinyl acetate and a copolymerizable monomer. In addition, the polyvinyl-based resin is a copolymerized polymer or a saponified polymer, for example, a modified polymer in which anionic groups such as carboxylic acid, sulfonic acid and phosphoric acid are introduced, and crosslinking such as diacetone acrylamide group, acetoacetyl group and mercapto group. And modified polymers incorporating reactive functional groups.

Further, examples of the monomer copolymerizable with vinyl acetate include unsaturated carboxylic acids such as maleic acid, fumaric acid, crotonic acid, itaconic acid, and (meth)acrylic acid, and esters thereof; Α-olefins such as ethylene and propylene; Olefinsulfonic acid which may have a carboxyl group, such as (meth)acrylic sulfonic acid, ethylene sulfonic acid, maleate sulfonate; Alkyl olefin sulfonate which may have a carboxyl group and/or an alkoxycarbonyl group, such as (meth)acrylic sulfonate soda, ethylene sulfonate soda, sulfonate soda (meth)acrylate, sulfonate soda (monoalkyl malate), disulfonate soda alkyl malate, etc. salt; Amide group-containing monomers such as N-methylolacrylamide and acrylamide alkylsulfonic acid alkali salts; Pyrrolidone group-containing monomers such as N-vinylpyrrolidone and N-vinylpyrrolidone derivatives; And the like.

Examples of the phenol resin include polyphenols (phenol, naphthol, bisphenol, etc.) and formaldehyde, and low molecular weight water-soluble resins or emulsion resins. Among these, a resol type phenol resin having a methylol group having self-condensation is preferable.

Examples of the natural polymer include cellulose, starch, dextrin, inulin, xanthan gum, tamarind gum, tannic acid, and lignin sulfonic acid.

As a polyolefin resin, Polypropylene; Polyethylene; Copolymers of propylene or ethylene with α-olefins; And polyolefins, modified polyolefins obtained by modifying the polyolefins with unsaturated carboxylic acids (for example, acrylic acid or methacrylic acid), and resins such as copolymers of ethylene and acrylic acid (methacrylic acid). A small amount of another ethylenically unsaturated monomer may be copolymerized with these resins. As a means for dissolving these polyolefin-based resins in water or dispersing them in water, means for neutralizing the carboxyl group contained in the polyolefin-based resin with ammonia or amines can be mentioned.

The number average molecular weight of the organic polymer is preferably 1000 to 1000000. Moreover, as long as this polymer resin does not inhibit the effect of this invention, it may have a crosslinking reactive functional group. In addition, the number average molecular weight can be measured by GPC method (Gel Permeation Chromatography). More specifically, the difference in refractive index can be measured with a GPC device (HLC-8220; manufactured by Tosoh Corporation) equipped with a differential refractometer (RI) detector, and calculated in terms of polystyrene (hereinafter the same).

The organic polymer (component c) contained in the surface treatment agent is preferably 95% or less, and more preferably 90% or less, as an upper limit in terms of the solid content conversion ratio with respect to the total mass of solid content in the surface treatment agent. On the other hand, the lower limit is preferably 5% or more, and more preferably 10% or more. By containing the organic polymer (component c) in the surface treatment agent in the range of this ratio, the film formability of the temporary layer can be improved, and a dense surface treatment film can be formed to improve the corrosion resistance.

Examples of the additive for the surface treatment agent include antifoaming agents, leveling agents, stabilizers, rust inhibitors, antibacterial agents, antifungal agents, wetting agents, thickeners, etc., which are known additives, and one or two or more of them can be used. have. Specifically, in addition to the solvent and component a and component b (component c, if necessary), an antifoaming agent, leveling agent, stabilizer, antirust agent, antibacterial agent, antifungal agent, wetting agent, or surface treatment agent blending thickener, or solvent and component a In addition to and component b (component c) as needed, anti-foaming and leveling agents, anti-foaming and stabilizing agents, anti-foaming and anti-rusting agents, anti-foaming and wetting agents, leveling and stabilizing agents, leveling and anti-rusting agents, leveling and wetting agents, stabilizers and anti-rusting agents , A stabilizer and a wetting agent, a rust inhibitor and a wetting agent, an antibacterial agent and an antifungal agent, or a surface treatment agent containing a stabilizer, an antibacterial agent and an antifungal agent.

As the antifoaming agent, for example, mineral oil antifoaming agents, fatty acid antifoaming agents, silicone antifoaming agents, and the like can be used. Moreover, you may mix|blend both with a surface treatment agent. As the leveling agent, known compounds such as nonionic or cationic surfactants, polyethylene oxide or polypropylene oxide adducts of polyacetylene glycol, and acetylene glycol compounds can be used, for example. As the stabilizer, for example, known chelating agents such as ethanolamines, tartaric acid, citric acid, lactic acid, gluconic acid, glycolic acid, and salts thereof may be used, and these may be used alone, but two or more kinds may be used in combination. May be Examples of the ethanolamines include, but are not limited to, monoethanolamine, diethanolamine, triethanolamine, and the like. As a thickener, For example, sodium salt, potassium salt, or ammonium salt, such as hydroxyethyl cellulose and carboxymethyl cellulose; Polyethylene glycol; Polyvinylpyrrolidone; Copolymers of vinylpyrrolidone and vinyl acetate; Polyvinyl alcohol partially saponified with polyvinyl acetate resin; Etc. can be used. Further, the surface treatment agent may or may not include hindered amines, which are radical scavengers. Here, the hindered amines means a compound having a structure in which a carbon atom is bonded directly to an nitrogen atom of the piperidine ring or through an oxygen atom.

When the pH of the surface treatment agent is 7 or less, the oxidizing power of nitrate ions becomes strong, and when the surface treatment agent is brought into contact with the metal material, the oxide film obtained on the surface of the metal material becomes thick, adhesion between the surface treatment film and the metal material surface decreases, and corrosion resistance Falls. Further, when the pH of the surface treatment agent is more than 12, the oxidizing power of nitrate ions is weakened, and when the surface treatment agent is brought into contact with the metal material, a dense oxide film is not obtained on the surface of the metal material, and corrosion resistance is lowered. Therefore, pH of the surface treatment agent which concerns on this invention was made into 7 or more and 12 or less. Moreover, pH of a preferable surface treatment agent is 7.5 or more and 12 or less, and pH of a more preferable surface treatment agent is 8 or more and 11 or less. In addition, the pH defined in the present specification and claims refers to a value measured at 25°C.

(Method of manufacturing surface treatment agent)

The manufacturing method of the surface treatment agent which concerns on this invention is not specifically limited. For example, a stirrer such as a mixing mixer, an alkali metal salt of zirconium carbonate (component a), nitrate (component b), a solvent, and if necessary, an organic polymer (component c) and/or other additives, etc. It can be produced by sufficiently mixing using.

The solvent is not particularly limited, but an aqueous solvent is preferred. The aqueous solvent means that it contains 50% by mass or more of water, based on the mass of the total solvent. In addition, "solvent" does not mean a solvent having a narrow meaning of dissolving all components, but is a concept including a dispersion medium that may be in a dispersed state for some components. Examples of the solvent other than water included in the aqueous solvent include, for example, alkane-based solvents such as hexane and pentane; Aromatic solvents such as benzene and toluene; Alcohol solvents such as ethanol, 1-butanol, and ethyl cellosolve; Ether-based solvents such as tetrahydrofuran and dioxane; Ester solvents such as ethyl acetate and butoxyethyl acetate; Amide solvents such as dimethylformamide and N-methylpyrrolidone; Sulfone solvents such as dimethyl sulfoxide; Phosphate amide solvents such as hexamethylphosphate triamide; And the like. These solvents other than water may be used alone or in combination of two or more. Moreover, you may use only water as a solvent.

(Metal material)

Next, a method of manufacturing a metal material according to the present invention will be described. The method includes a step of bringing a surface treatment agent into contact with the surface of the metal material (contact step) and a step of drying the surface of the metal material in contact with the surface treatment agent (drying step). Moreover, generally, the said method is a degreasing process and a water washing process before the said contact process. Further, in the method, after the drying step, a step of contacting a known top coat paint may be performed to form a top coat (coating) on the coat formed by the surface treatment agent.

As a method of bringing the surface treatment agent into contact, a conventional method can be applied, and it can be carried out, for example, by roll coating, curtain flow coating, air spraying, airless spraying, dipping, bar coating, brush application, or the like.

The surface of the metal material in contact with the surface treatment agent can be dried by a conventional method, for example, heat drying or air drying. Further, the drying temperature is not particularly limited as long as the surface of the metal material can be dried, but the maximum reaching temperature (PMT) of the metal material is suitable in the range of 40 to 200°C, and more preferably in the range of 60 to 150°C. By drying in the range of 60°C to 150°C, the adhesion between the film formed by the surface treatment agent and the metal material or the top coat can be improved.

In addition, the target metal materials are cold rolled steel sheet, hot rolled steel sheet, hot dip galvanized steel sheet, electro galvanized steel sheet, hot dip galvanized steel sheet, aluminum plated steel sheet, aluminum-zinc alloy plated steel sheet, tin-zinc alloy plated steel sheet, zinc-nickel Steel materials such as alloy plated steel sheet and stainless steel sheet; Aluminum material; Aluminum alloy material; Copper materials; Copper alloy material; Titanium material; Titanium alloy material; Magnesium material; It can be applied to generally known metal materials or plating materials such as magnesium alloy materials. Among them, an aluminum material or an aluminum alloy material is preferable. Moreover, the metal material which contacts the surface treatment agent which concerns on this invention may be what mixed several types of materials. These metal materials may be subjected to ordinary treatments such as hot water washing and alkali degreasing before surface treatment with a surface treatment agent.

Next, the metal material on which the film is formed by the surface treatment will be described. First, it is preferable that the coating mass of the formed film is in the range of 0.01 to 1 g/m 2 (dry mass). Adhesiveness can be improved by having a film mass in this numerical range. Moreover, a more preferable range is in the range of 0.02 g/m 2 to 0.5 g/m 2.

Next, a method (use) of using the metal material on which the film is formed by the surface treatment agent will be described. First, various metal products can be obtained by processing the metal material into a desired shape. Examples of the metal products include galvanized steel sheets for anti-fingerprint applications, pre-coated steel sheets for houses for construction use, aluminum fin materials for air conditioners, and various metal parts for automobiles. In addition, the top coat formed on the film is not particularly limited, and for example, as the top coat, an electrodeposition coating film, a solvent coating film, a powder coating film and a special coating film, such as a hydrophilic coating layer, a lubricating organic coating layer, and an anti-microbial coating And the like.

Example

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. The present invention is not limited by the following examples.

[Metal material]

The metal material used as a base material is shown below.

Aluminum plate (A1050P; JIS H 4000-2014)

Cold rolled steel sheet (SPCC-SD; JIS G 3141-2011)

Hot-dip galvanized steel sheet [GI: 60 g/m 2 per side of zinc adhesion (double-sided plating); JIS G 3302-2012]

[Surface treatment agent]

As shown in Table 1 to Table 3, each surface treatment agent used to prepare the test materials of Examples 1 to 31 and Comparative Examples 1 to 9, 11 to 18, and 20 to 24 was prepared. In addition, water was used as a solvent. In addition, pH was adjusted using ammonia or acetic acid. "Component C concentration" in each table shows the non-volatile component concentration (mass%) of component C with respect to the total solid content mass in the surface treatment agent. In addition, each symbol shown in the column of "component A", "component B", and "component C" in each table represents the following substances, respectively. "MB/MA" in each table shows the mass ratio of the total mass (MA) of Zr in component A and the total mass (MB) of anions in component B to be blended with the surface treatment agent. In addition, the solid content concentration of each surface treatment agent was appropriately adjusted so that the amount of the coating formed by the surface treatment agent was 50 mg/m 2.

[Component A]

A1: sodium zirconium carbonate

A2: lithium zirconium carbonate

A3: Potassium zirconium carbonate

A4: Zirconium ammonium carbonate

[Component B]

B1: sodium nitrate

B2: potassium nitrate

B3: ammonium nitrate

B4: sodium sulfate

B5: sodium phosphate

[Component C (Organic Polymer)]

(Component C1: Urethane resin-anionic)

Polyester polyol (adipic acid/3-methyl-1,5-pentanediol, number average molecular weight: 1000, number of functional groups: 2, hydroxyl value: 112.2) 100 parts by mass, trimethylolpropane 3 parts by mass, dimethylol propionic acid 25 The urethane prepolymer was obtained by reacting parts by mass and 85 parts by mass of isophorone diisocyanate in MEK (methyl ethyl ketone). After mixing 9.4 parts by mass of triethylamine in the reaction mixture, it was dispersed in water and extended with ethylenediamine. Then, methyl ethyl ketone was distilled off to obtain an aqueous urethane resin dispersion containing 30% by mass of nonvolatile matter. The acid value of the carboxyl group-containing polyurethane in the obtained urethane resin aqueous dispersion was 49 (KOH mg/g).

(Component C2: Epoxy resin-anionic)

To a mixture of 85 g of orthophosphoric acid and 140 g of propylene glycol monomethyl ether, 425 g of bisphenol A-type epoxy resin having an epoxy equivalent of 250 was added little by little, and reacted at 80°C for 2 hours. After completion of the reaction, 150 g of a 29% by mass aqueous ammonia solution was added little by little at 50°C or less, and 1150 g of water was added, and an ammonia neutralized product of a phosphate-modified epoxy resin having an acid value of 35 (KOH mg/g) and a solid content concentration of 25% by mass Got

(Component C3: Acrylic resin-nonionic)

As a monomer composition, "20 parts by mass of methyl methacrylate (molecular weight: 100), 40 parts by mass of butyl acrylate (molecular weight: 128), 10 parts by mass of 2-hydroxypropyl methacrylate (molecular weight: 144), styrene (molecular weight : 104) 10 parts by mass and N,N-dimethylaminopropyl methacrylate (molecular weight: 175) 20 parts by mass" were used. Synthesis of component C3 was performed as follows. 10% by mass aqueous solution of an emulsifier (S-1) in which a reactive emulsifier ``Adeka Rear Shock NE-20'' (manufactured by ADEKA) and a nonionic emulsifier ``Emulgen 840S'' (manufactured by Kao Corporation) were mixed at 6:4. ) 100 parts, the above monomers were mixed and emulsified at 5000 rpm for 10 minutes using a homogenizer to obtain a monomer emulsion (ER). Subsequently, the temperature was maintained at 40 to 50°C, and 5 parts by weight of an aqueous solution of ammonium persulfate (50 parts) and monomer emulsion (ER) were added dropwise over 150 hours to 150 parts of an emulsifier aqueous solution (S-1). Thereafter, the temperature was raised to 60°C and stirred for about 1 hour. Subsequently, the mixture was cooled to room temperature while stirring to obtain an acrylic resin emulsion solution.

(Component C4: Polyester resin-anionic)

Alcohol components including ethylene glycol (90 mol%) and trimethylolpropane (10 mol%), isophthalic acid (40 mol%), terephthalic acid (41 mol%), dimethyl isophthalate-5-sodium sulfonate (2 mol%), and trimelli anhydride Anionic polyester resin (solid content (NVC.) 30%) by a condensation reaction of an acid component containing triacid (17 mol%) was synthesized as follows. Under a nitrogen atmosphere, a mixture of 1 mol of the total acid component and 2 mol of the total alcohol component and the catalyst (0.25 g of calcium acetate, 0.1 g of N-butyl titanate) was heated to 180°C to melt. Thereafter, the mixture was heated to 200°C, stirred with heating for about 2 hours, and subjected to esterification or transesterification reaction. Further, the mixture was heated to 260°C, and after about 15 minutes, the system was decompressed to 0.5 mmHg to react for about 3 hours (polycondensation reaction). After completion of the reaction, the mixture was allowed to cool under a nitrogen atmosphere. Ammonia water (water is an amount of 25% solid content) was added to the reaction product to adjust the pH to 6-7, followed by heating and stirring at 100°C for 2 hours to obtain a polyester resin of an aqueous emulsion.

(Component C5: Polyvinyl alcohol-nonionic)

A saponification degree: 99%, a viscosity: 12 mPa·S, an acetylation degree: 9.8%, and an acetylated polyvinyl alcohol having a number average molecular weight: 50000 were used.

[Production of test materials]

Each substrate was degreased by spraying a 3% aqueous solution of Fine Cleaner 359E (available from Nippon Parkerizing Co., Ltd.) at 65°C for 1 minute, followed by washing with water to wash the surface. Subsequently, in order to evaporate moisture on the surface of the substrate, it was heated and dried at 80°C for 1 minute. On the surface of the degreasing washed substrate, each surface treatment agent was applied by a bar coat method using a #3SUS Meyer bar, dried at 115°C for 30 seconds in a hot air circulation drying furnace, and a surface treatment film was formed on the surface of the substrate. . Then, using a #5SUS Meyer bar, a coating material containing an acrylic-modified epoxy resin was applied to the coating amount of 1.7 g/m 2 by a bar coat method, and dried at 255° C. for 20 seconds in a hot-air circulation type drying furnace. Produced test materials. In addition, the test materials of Comparative Examples 10, 19, and 25 shown in Tables 1 to 3 were prepared by degreasing each substrate as described above, followed by washing with water and drying by heating (untreated plate).

[Performance evaluation]

The liquid stability of each surface treatment agent and the corrosion resistance of each test material were evaluated as follows. The results are shown in Tables 1 to 3.

(Evaluation of liquid stability)

300 g of a drug was added to a 1300 ml tall beaker (opening area: 0.31 cm 2 ), and stirring was continued under open conditions while maintaining the liquid temperature at 70°C. In addition, during stirring, in order to maintain the solid content concentration, replenishment of pure water was performed at 30 minute intervals, the time until thickening was measured, and liquid stability was evaluated according to the following evaluation criteria.

<Evaluation criteria>

○: 5 hours or more, ×: 5 hours or less

(Corrosion resistance)

When the metal material is an aluminum plate, after cross-cutting each test material, a 5 wt% aqueous solution of sodium chloride is adjusted to pH 3.0 to 3.1 with acetic acid, and the acetic acid salt spray test is performed at 35°C to 300°C. Time was conducted. Thereafter, exposure was performed for 96 hours under a constant temperature and humidity environment of 80°C and 70%, and the maximum length of the eventual rust was measured to evaluate corrosion resistance according to the following evaluation criteria.

<Evaluation criteria>

6 points: Maximum finishing rust length 0 mm, 5 points: Maximum finishing rust length exceeding 0 mm and 1 mm or less, 4 points: Maximum finishing rust length exceeding 1 mm to 2 mm or less, 3 points: Maximum finishing rust length exceeding 2 mm to 3 mm or less, 2 points: Maximum finishing rust length greater than 3 mm to 6 mm or less, 1 point: Maximum finishing rust length exceeding 6 mm to 10 mm or less

When the metal material is a cold rolled steel sheet, after cross-cutting each test material, a salt spray test with 5 wt% sodium chloride solution is performed at 35° C. until the maximum rust width on one side of the cut reaches 3 mm. The time was measured, and corrosion resistance was evaluated according to the following evaluation criteria.

<Evaluation criteria>

6 points: 480 hours or more, 5 points: 400 hours or more and less than 480 hours, 4 points: 320 hours or more and less than 400 hours, 3 points: 240 hours or more and less than 320 hours, 2 points: 120 hours or more and less than 240 hours, 1 point: 0 hours or more and less than 120 hours

When the metal material is a hot-dip galvanized steel sheet, after cross-cutting each test material, a salt spray test with 5 wt% sodium chloride solution is performed at 35°C, and the maximum rust width on one side of the cut reaches 3 mm. The time until was measured, and corrosion resistance was evaluated according to the following evaluation criteria.

<Evaluation criteria>

6 points: 720 hours or more, 5 points: 640 hours or more and less than 720 hours, 4 points: 560 hours or more and less than 640 hours, 3 points: 480 hours or more and less than 560 hours, 2 points: 240 hours or more and less than 480 hours, 1 point: 0 hours or more and less than 240 hours

It was confirmed that the test materials of Examples 1 to 17 in Table 1, Examples 18 to 26 in Table 2, and Examples 27 to 31 in Table 3 were excellent in corrosion resistance. In addition, the surface treatment agents used to prepare the test materials of Examples 1 to 17 of Table 1, Examples 18 to 26 of Table 2, and Examples 27 to 31 of Table 3 did not thicken even after 72 hours in liquid stability evaluation. It was confirmed that the liquid stability was very excellent.

Claims (4)

Surface treatment agent for metallic materials, containing an alkali metal salt of zirconium carbonate (component a) and a nitrate (component b) and having a pH of 7 or more and 12 or less (but not containing any elements of fluorine, vanadium and cobalt) . According to claim 1, Urethane resin, epoxy resin, acrylic resin, phenol resin, polyester resin, polyvinyl resin, polyolefin resin and one or two or more organic polymers selected from natural polymers (component c) The surface treatment agent for metal materials which further contains. The surface treatment agent for metal materials according to claim 1, wherein the pH is 7.5 or more and 12 or less. A metal material having a surface-treated film formed by bringing the surface treating agent for a metal material according to any one of claims 1 to 3 into contact with a surface of a metal material and then drying it.