WO2012165084A1

WO2012165084A1 - Aqueous surface treatment agent for metal

Info

Publication number: WO2012165084A1
Application number: PCT/JP2012/060881
Authority: WO
Inventors: 宇留嶋　秀人; 友哉木村; 彰典永井; 崇大久保; 多佳士中野
Original assignee: 関西ペイント株式会社
Priority date: 2011-05-27
Filing date: 2012-04-23
Publication date: 2012-12-06

Abstract

　Provided is an aqueous surface treatment agent for metals that contains a predetermined quantity of: a binder component comprising a mixture, or hydrolytic condensate of said mixture, of 30-70 parts by mass of a tetraalkoxysilane or a low condensate thereof, 70-30 parts by mass of a silica coupling agent containing an epoxy group or an amino group, and 0-40 parts by mass of a mono/di/trialkoxysilane or a low condensate thereof; a phosphate compound; a vanadium compound; and a zirconium compound or a titanium compound. The surface treatment agent for metals forms a chromate-free surface treatment film exhibiting superior coating properties and storage stability, as well as corrosion resistance, adhesion and electrical conductivity.

Description

Aqueous metal surface treatment agent

The present invention is excellent in paintability and storage stability, and has excellent corrosion resistance, adhesion and conductivity, and does not contain a pollution control substance such as hexavalent chromium in the film, that is, forms a chromate-free surface treatment agent film. The present invention relates to an aqueous metal surface treatment agent that can be used, a surface treatment method of a metal material using the surface treatment agent, and a surface treatment metal material on which a film is formed by the surface treatment agent.

As a technology that provides excellent adhesion to the metal material surface and imparts corrosion resistance to the metal material surface, in general, chromate treatment is performed on the metal material surface with a treatment liquid containing chromic acid, dichromic acid or a salt thereof as a main component. , A method of performing a phosphate treatment, a method of performing a treatment with a specific inorganic component, a method of performing a treatment with a silane coupling agent, a method of performing an organic resin film treatment, etc. are already known and are already in practical use. Has been.

As a method for performing treatment with a specific inorganic component, for example, Japanese Patent Application Laid-Open No. 2002-30460 discloses a metal compound containing a vanadium compound and at least one metal selected from zirconium, titanium, molybdenum, tungsten, manganese, and cerium. The method of performing the process by the metal surface treating agent containing these is disclosed.

As a treatment using a silane coupling agent, for example, in Japanese Patent Application Laid-Open No. 11-43647, a surface treatment agent containing an organofunctional silane and polysiloxane is used to form a siloxane film with improved adhesion to a substrate. A method of caulking is disclosed.

As a method for performing an organic resin film treatment, for example, Japanese Patent Application Laid-Open No. 2003-105562 discloses a specific resin compound, at least one cation selected from a primary, secondary, or tertiary amino group and a quaternary ammonium base. A cationic urethane resin having a functional functional group, at least one silane coupling agent having a specific reactive functional group, and a specific acid compound, and the cationic urethane resin and the silane coupling agent. A non-chromium surface-treated steel sheet that is treated with a surface treating agent having a content within a predetermined range and has excellent corrosion resistance, fingerprint resistance, blackening resistance, and paint adhesion is disclosed.

Japanese Patent Application Laid-Open No. 2010-255105 includes a water-soluble zirconium compound, a compound having an epoxy group, a chelating agent, a vanadic acid compound, and a metal compound containing a metal such as Ti. It is disclosed that a galvanized steel sheet having a surface treatment agent film formed from a surface treatment agent having a mass ratio of Zr equivalent weight / tetraalkoxysilane of a compound of 1.0 to 6.0 is excellent in corrosion resistance and electromagnetic shielding properties. Has been.

However, these conventional metal surface treatment agents simultaneously satisfy all the requirements of being excellent in paintability and storage stability, forming a film excellent in corrosion resistance, adhesion and conductivity, and being chromate-free. It does not satisfy, and it still has a problem since it is put into practical use.

JP 2002-30460 A JP 11-43647 A JP 2003-105562 A JP 2010-255105 A

The object of the present invention is to overcome the problems of the prior art as described above, and to control pollution of hexavalent chromium in the film, which is excellent in paintability and storage stability, and excellent in corrosion resistance, adhesion and conductivity. An object of the present invention is to provide an aqueous metal surface treatment agent capable of forming a chromate-free surface treatment agent film containing no substance.

An object of the present invention is also to provide a surface treatment method for a metal material such as a zinc-based plated steel sheet using the surface treatment agent and a surface treatment metal material on which a film is formed by the surface treatment agent.

As a result of intensive studies to achieve the above object, the present inventors have now obtained a binder component prepared from a tetraalkoxysilane (low condensate) and an epoxy group-containing silane coupling agent, and a phosphate compound, It has been found that the above problems can be solved by an aqueous surface treatment agent containing a specific amount of a vanadic acid compound and a zirconium compound or a titanium compound, and the present invention has been completed.

Thus, the present invention
(A) 30 to 70 parts by mass of at least one tetraalkoxysilane and tetraalkoxysilane low condensate;
(B) 30 to 70 parts by mass of at least one silane coupling agent selected from an epoxy group-containing silane coupling agent and an amino group-containing silane coupling agent;
(C) at least one mono-, di- or tri-alkoxysilane and / or at least one low-condensate mono-, di- or tri-alkoxysilane 0 to 40 parts by weight of mixture (I) or mixture A binder component (A) comprising a hydrolysis condensate (II) obtained by subjecting (I) to a hydrolysis condensation reaction,
(D) a phosphoric acid compound,
An aqueous metal surface treatment agent comprising (e) a vanadium compound, and (f) a zirconium compound or (f ′) a titanium compound,
Per 100 parts by weight of the total of the components (a), (b) and (c),
2-60 parts by mass of the phosphoric acid compound (d) and 1-50 parts by mass of the vanadium compound (e), and the zirconium compound (f), the Zr equivalent mass of the component (f) and the above (a) The mass ratio (f) / (a) with the component is 0.02 or more and less than 1.0, or the titanium compound (f ′) is added in the above (a), (b) and ( An aqueous metal surface treatment agent characterized by containing 0.1 to 100 parts by mass per 100 parts by mass of the total component c).

The present invention also includes coating the aqueous metal surface treatment agent on the surface of the metal material so that the dry film mass is in the range of 0.05 to 1.5 g / m ² and drying. A metal material surface treatment method is provided.

Furthermore, the present invention provides a surface treatment comprising a coating of the aqueous metal surface treatment agent on the surface of a metal material in an amount in the range of 0.05 to 1.5 g / m ² in terms of dry coating mass. A metal material is provided.

The aqueous metal surface treatment agent of the present invention is a chromate-free surface treatment agent that does not contain pollution control substances such as hexavalent chromium, and is excellent in paintability and storage stability. Moreover, the film formed from the metal surface treatment agent of the present invention satisfies all of the corrosion resistance, adhesion and conductivity at the same time, such as a zinc-based plated steel sheet on which the surface treatment agent film is formed. Since the metal material is excellent in conductivity and excellent in corrosion resistance even when the surface treatment agent film is thin, a surface treatment metal material having a thin surface treatment agent film and excellent in conductivity can be obtained.

Aqueous metal surface treatment agent The aqueous metal surface treatment agent of the present invention comprises a binder component (A), a phosphoric acid compound (d), a vanadium compound (e), and a zirconium compound (f) or a titanium compound (f ′), which are aqueous. It is dissolved or dispersed stably in the medium. In the present invention, the “aqueous medium” includes water and a mixture of water and an organic solvent, which have a water content of at least 80% by mass and form a uniform liquid at 20 ° C., or water. The organic solvent species that can constitute the “aqueous medium” is not particularly limited as long as it is a water-miscible solvent having water solubility or water dispersibility. For example, methanol, ethanol, isopropyl alcohol, t-butyl alcohol, Water-soluble organic solvents such as alcohols such as propylene glycol; glycol ethers such as ethylene glycol monobutyl ether and ethylene glycol monoethyl ether; esters such as ethyl acetate and butyl acetate; and ketones such as acetone are preferably used. it can.

Binder component (A)
The binder component (A) in the aqueous metal surface treatment agent of the present invention is at least one of tetraalkoxysilane and tetraalkoxysilane low-condensate (a), an epoxy group-containing silane coupling agent, and an amino group-containing silane. At least one silane coupling agent (b) selected from coupling agents, and optionally (c) at least one of mono-, di- or tri-alkoxysilanes and / or mono-, di- Alternatively, it comprises a mixture (I) of at least one low-condensate of tri-alkoxysilane or a hydrolysis condensate (II) obtained by subjecting the mixture (I) to a hydrolysis condensation reaction.

( A) Component The tetraalkoxysilane in component (a) as one component of binder component (A) has one silicon atom and four alkoxy groups directly bonded to the silicon atom in one molecule. The alkoxy group is not particularly limited, but usually an alkoxy group having 1 to 4 carbon atoms is preferable, particularly an alkoxy group having 1 to 3 carbon atoms, more particularly 1 or 2 carbon atoms is preferable. Specific examples of such alkoxysilanes include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, dimethoxydiethoxysilane, and the like, and these can be used alone or in combination of two or more. Of these, tetraethoxysilane and tetramethoxysilane are preferred from the viewpoint of better corrosion resistance of metal materials, particularly zinc-based plated steel sheets.

The low-condensation product of tetraalkoxysilane that can be used as the component (a) includes the low-condensation product of tetraalkoxysilane as exemplified above, and may be a low-condensation product of one kind of tetraalkoxysilane alone. Alternatively, it may be a low condensate of at least two tetraalkoxysilanes. The low-condensation product of tetraalkoxysilane generally has a degree of polymerization of generally 10 or less, particularly 2 to 8, more particularly 2 to 6.

(B) The silane coupling agent (b) used as one component of the component binder component (A) is at least one silane coupling agent selected from an epoxy group-containing silane coupling agent and an amino group-containing silane coupling agent. It is.

The epoxy group-containing silane coupling agent has at least one, preferably only one epoxy group and 1 to 3 alkoxy groups (usually 1 to 4 carbon atoms, particularly 1 to 4 carbon atoms) per molecule. 3 and more particularly silane compounds containing 1 or 2 carbon atoms), specifically, for example, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane Γ-glycidoxypropyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, and the like.

The amino group-containing silane coupling agent has at least 1, preferably 1 or 2 amino groups and 1 to 3 alkoxy groups (usually 1 to 4 carbon atoms, particularly 1 carbon atom) in one molecule. -3, and more particularly silane compounds containing 1 or 2 carbon atoms), specifically, for example, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, N- ( 2-aminoethyl) 3-aminopropylmethyldimethoxysilane, N- (aminoethyl) 3-aminopropyltrimethoxysilane and the like.

(C) Component In the binder component (A), the component (c) is an optional component used as necessary, and is at least one of mono-, di- or tri-alkoxysilane and / or mono-, di- Alternatively, it includes at least one low-condensate of tri-alkoxysilane, and the alkoxy group is not particularly limited, but usually an alkoxy group having 1 to 4 carbon atoms is preferable, particularly 1 to 3 carbon atoms, An alkoxy group having 1 or 2 carbon atoms is particularly preferable.

Examples of the monoalkoxysilane include alkoxytrialkylsilanes such as methoxytrimethylsilane, methoxytriethylsilane, methoxymethyldiethylsilane, ethoxytrimethylsilane, ethoxytriethylsilane, propoxytrimethylsilane, propoxytripropylsilane, and butoxytributylsilane; ethoxy Examples thereof include alkoxytriphenylsilane such as triphenylsilane.

Examples of the dialkoxysilane include dimethoxydimethylsilane, dimethoxydiethylsilane, diethoxydimethylsilane, diethoxydiethylsilane, diethoxydiphenylsilane, dipropoxydimethylsilane, dipropoxydiethylsilane, dipropoxydipropylsilane, dibutoxy. Examples include dialkoxydialkylsilanes such as dimethylsilane, dibutoxydiethylsilane, and dibutoxydibutylsilane; dialkoxydiphenylsilanes such as dimethoxydiphenylsilane, dipropoxydiphenylsilane, and dibutoxydiphenylsilane.

Examples of the trialkoxysilane include trimethoxymethylsilane, trimethoxyethylsilane, trimethoxypropylsilane, trimethoxybutylsilane, triethoxymethylsilane, triethoxyethylsilane, triethoxybutylsilane, tripropoxymethylsilane, And trialkoxyalkylsilanes such as propoxypropylsilane; trialkoxyphenylsilanes such as trimethoxyphenylsilane, triethoxyphenylsilane, tripropoxyphenylsilane, and tributoxyphenylsilane.

At least one low-condensate of mono-, di- or tri-alkoxysilane that can be used as component (c) is a single low-condensate of mono-, di- or tri-alkoxysilane. Alternatively, it may be a low condensate of at least two mono-, di- or tri-alkoxysilanes. The low condensate preferably has a degree of polymerization of generally 10 or less, particularly 2 to 8, more particularly 2 to 6.

The blending ratio of each component constituting the binder component (A) is in the following range per 100 parts by mass in total of the components (a), (b) and (c) from the viewpoint of the corrosion resistance and adhesion of the resulting film. It is preferable to be within.
Component (a): 30 to 70 parts by weight, particularly 35 to 65 parts by weight, more particularly 40 to 60 parts by weight,
Component (b): 30 to 70 parts by weight, particularly 35 to 65 parts by weight, more particularly 40 to 60 parts by weight,
Component (c): 0 to 40 parts by mass, particularly 0 to 30 parts by mass, more particularly 0 to 20 parts by mass.

The binder component (A) in the aqueous metal surface treatment agent of the present invention is a mixture of the component (a) and the component (b) or a mixture of the component (a), the component (b), and the component (c). It can be the mixture (I) or, preferably, the hydrolysis condensate (II) obtained by subjecting the mixture (I) to a hydrolysis condensation reaction. The hydrolysis-condensation product (II) usually has a weight average molecular weight in the range of 200 to 20,000, preferably 300 to 10,000. The weight average molecular weight can be measured by GPC (gel permeation chromatograph) measurement or by confirming the number of siloxane bonds by condensation by ²⁹ Si NMR (nuclear magnetic resonance spectrum) measurement. .

The hydrolysis condensation reaction of the above mixture (I) can be carried out according to a method known per se, for example, in the presence of water and an acid catalyst. The acid catalyst is not particularly limited as long as it is an acid usually used as a catalyst for the hydrolysis reaction of alkoxysilane. For example, inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid; formic acid, acetic acid, Examples thereof include organic acids such as lactic acid and tartaric acid. Among them, inorganic acids, particularly hydrochloric acid can be preferably used. In the hydrolysis condensation reaction, an organic solvent, particularly a water-miscible organic solvent that dissolves the mixture (I) (for example, an alcohol solvent or a glycol ether solvent) may be used as appropriate. Among them, for example, alcohol solvents such as methanol, ethanol and propanol are suitable. The hydrolysis reaction can usually be carried out by stirring at a temperature of about 20 ° C. to 100 ° C. for about 30 minutes to 20 hours at a pH of 7 or less, preferably at a pH of 1.5 to 6.0. A condensation reaction proceeds with the hydrolysis reaction. The composition of the hydrolysis-condensation product (II) obtained by this reaction can be appropriately adjusted depending on the amount of water used, the type and amount of the catalyst, the reaction temperature, the reaction time, and the like.

Phosphoric acid compound (d)
The phosphoric acid compound which is the component (d) in the metal surface treatment agent of the present invention contributes to the improvement of the storage stability of the metal surface treatment agent, and the alkoxysilyl group in the binder component (A) reacts. It is presumed that it acts to suppress the increase in molecular weight.

The type of the phosphoric acid compound (d) is not particularly limited, and may be an organic phosphoric acid compound or an inorganic phosphoric acid compound. Specific examples of the organic phosphate compound include 1-hydroxymethane-1,1-diphosphonic acid, 1-hydroxyethane-1,1-diphosphonic acid, 1-hydroxypropane-1,1-diphosphonic acid, and the like. Suitable examples include hydroxyl group-containing organic phosphorous acid; carboxyl group-containing organic phosphorous acid such as 2-hydroxyphosphonoacetic acid and 2-phosphonobutane-1,2,4-tricarboxylic acid, and salts thereof. . Specific examples of the inorganic phosphoric acid compound include orthophosphoric acid, metaphosphoric acid, phosphorous acid, metaphosphorous acid, hypophosphoric acid, hypophosphorous acid, pyrophosphoric acid, tripolyphosphoric acid, tetraphosphoric acid, hexaphosphoric acid, Examples include trimetaphosphoric acid, pyrophosphorous acid, and phosphoric acid derivatives; alkali metal salts or ammonium salts of these phosphoric acid compounds.

Among the phosphoric acid compounds, 1-hydroxyethane-1,1 is particularly preferable because it has a great effect of suppressing the reaction of alkoxysilyl groups in the binder component (A) and improving the storage stability of the metal surface treatment agent. Diphosphonic acid is particularly preferred.

Vanadium compound (e)
The vanadium compound as the component (e) in the metal surface treatment agent of the present invention is useful as a component that exhibits an inhibitory effect on corrosion of a metal material such as a zinc-based plated steel sheet on which a film of the metal surface treatment composition is formed.

Examples of the vanadium compound (e) include lithium metavanadate, potassium metavanadate, sodium metavanadate, ammonium metavanadate, anhydrous vanadic acid, vanadium pentoxide, vanadium trioxide, vanadium dioxide, vanadium oxysulfate, vanadium sulfate, oxytrimethyl Examples thereof include vanadium chloride, vanadium trichloride, vanadium oxyacetylacetonate, vanadium acetylacetonate, and phosphovanadomolybdic acid, and these can be used alone or in combination of two or more.

As the vanadium compound (e), ammonium metavanadate is particularly preferable from the viewpoints of water adhesion of the film and corrosion resistance of the metal material after the film is alkali degreased.

Zirconium compound (f)
The zirconium compound which is the component (f) in the metal surface treatment composition of the present invention is a metal without practically reducing the conductivity of a metal material such as a zinc-based plated steel sheet on which a film of the metal surface treatment agent is formed. It contributes to improving various performances such as corrosion resistance of the material, adhesion of the formed film, and corrosion resistance of the metal material after alkali degreasing the film.

The type of the zirconium compound (f) is not particularly limited, but is preferably water-soluble. Specifically, for example, zirconium nitrate, zirconium oxynitrate, zirconyl acetate, zirconyl sulfate, zirconium carbonate, carbonic acid Zirconyl ammonium, potassium zirconyl carbonate, sodium zirconyl carbonate, lithium zirconyl carbonate, zirconium hydrofluoric acid (H ₂ ZrF ₆ ); sodium hydrofluoric acid (H ₂ ZrF ₆ ) sodium salt, potassium salt, lithium salt and ammonium salt _[(NH ₄₎ 2 ZrF _6], and the like. these may be used alone or in combination of two or more.

As the zirconium compound (f), from the viewpoint that the corrosion resistance of the metal material such as the surface-treated galvanized steel sheet, conductivity, and the corrosion resistance of the metal material after alkali degreasing the film is more excellent, among them, zirconyl ammonium carbonate [(NH ₄ ) ₂ ZrO (CO ₃ ) ₂ ] and sodium zirconyl carbonate [Na ₂ ZrO (CO ₃ ) ₂ ] are preferred.

Titanium compound (f ')
The titanium compound that is the component (f ′) in the metal surface treatment composition of the present invention can be used without practically reducing the conductivity of a metal material such as a zinc-based plated steel sheet on which a film of the metal surface treatment composition is formed. It contributes to improving various properties such as the corrosion resistance of the metal material, the adhesion of the formed film, and the corrosion resistance of the metal material after alkali degreasing the film.

The type of the titanium compound (f ′) is not particularly limited, but is preferably water-soluble. Specifically, for example, titanyl sulfate, titanyl nitrate, titanium nitrate, titanyl chloride, titanium chloride, titania sol , Titanium oxide, potassium oxalate titanate, titanium hydrofluoric acid (H ₂ TiF ₆ ), titanium ammonium fluoride [(NH ₄ ) ₂ TiF ₆ ], titanium lactate, titanium tetraisopropoxide, titanium acetylacetonate, diisopropyl titanium Bisacetylacetone, metatitanic acid, metatitanate, orthotitanic acid, orthotitanate and the like can be mentioned, and these can be used alone or in combination of two or more.

As the titanium compound (f ′), the corrosion resistance of the metal material such as the surface-treated galvanized steel sheet, the conductivity, and the corrosion resistance of the metal material after alkali degreasing the film are particularly preferable. Hydroxy acid (H ₂ TiF ₆ ) and ammonium titanium fluoride [(NH ₄ ) ₂ TiF ₆ ] are preferred.

The blending amounts of the components (d) and (e) in the aqueous metal surface treatment agent of the present invention are as follows per 100 parts by mass in total of the components (a), (b) and (c) constituting the binder (A). Can be within the range.
Phosphoric acid compound (d): 2 to 60 parts by mass, preferably 5 to 45 parts by mass, more preferably 10 to 35 parts by mass,
Vanadium compound (e): 1 to 50 parts by mass, preferably 2 to 30 parts by mass,
More preferably 5 to 20 parts by mass.

The blending amount of the above components (d) and (e) is within the above range. Corrosion resistance of the resulting treatment agent film, in particular, corrosion resistance after alkaline degreasing treatment, conductivity, and surface treatment agent paintability and storage stability. From the viewpoint of sex.

The aqueous metal surface treatment agent of the present invention contains a zirconium compound (f) or a titanium compound (f ′).

In the aqueous metal surface treatment agent of the present invention, when the component (f) is blended, the blending amount thereof is the Zr equivalent mass of the zirconium compound (f) and the component (a) constituting a part of the binder component (A). The mass ratio (f) / (a) is 0.02 or more and less than 1.0, preferably 0.04 to 0.70, more preferably 0.10 to 0.50. be able to. When the mass ratio (f) / (a) is less than 0.02, the corrosion resistance of the resulting treatment agent film, particularly the corrosion resistance after the alkaline degreasing treatment, is inferior, while the mass ratio (f) / (a) is 1.0. When it becomes the above, the coating property and storage stability of a surface treating agent will fall, and there exists a tendency for the electroconductivity of the processing agent membrane | film | coat obtained to fall.

Furthermore, in the aqueous metal surface treatment agent of the present invention, when the component (f ′) is blended, the blending amount is a total of 100 components (a), (b) and (c) constituting the binder (A). The amount may be 0.1 to 100 parts by weight, preferably 2 to 40 parts by weight, and more preferably 5 to 30 parts by weight per part by weight. When the blending amount of the component (f ′) is within the above range, the corrosion resistance of the resulting coating film, particularly the corrosion resistance after alkaline degreasing treatment, conductivity, and the coating properties and storage stability of the surface treatment agent From the aspect, it is preferable.

Other Additive Components The aqueous metal surface treatment agent of the present invention comprises the binder component (A), phosphate compound (d), vanadium compound (e), zirconium compound (f) or titanium compound (f ′) and an aqueous medium. In addition, leveling agents, antifoaming agents, surfactants, colorants, antibacterial and antifungal agents; etching inhibitors that are amine compounds such as ethylenediamine, triethylenepentamine, guanidine, pyrimidine; acetic acid, lactic acid, ammonium salts, PH adjusters such as amines; waxes such as polyethylene wax, oxidized polyethylene wax, oxidized polypropylene wax, carnauba wax, paraffin wax, montan wax and tetrafluoroethylene wax; lubricants such as carbon disulfide, molybdenum disulfide and graphite ; Hydroxycarbos such as tartaric acid and malic acid Dicarboxylic acids such as acid, oxalic acid, malonic acid, succinic acid, citric acid and adipic acid; aminocarboxylic acids such as glycine; chelating agents such as EDTA and DTPA; metal compounds containing metals such as Al and Zn; A water-soluble organic resin having water solubility or water dispersibility can be appropriately contained, and among these, water-based organic resins and / or waxes are preferable.

The chelating agent is considered to have a function of stably dissolving the vanadium compound (e), the zirconium compound (f), and the titanium compound (f ′) in the surface treatment agent.

In the metal compound that can be appropriately blended in the aqueous metal surface treatment agent of the present invention, examples of the metal compound containing Al include aluminum oxide, aluminum hydroxide, aluminum sulfate, aluminum nitrate, aluminum phosphate, aluminum chloride and the like. Examples of the metal compound containing Zn include zinc carbonate, zinc oxide, zinc hydroxide, zinc sulfate, zinc nitrate, zinc chloride, zinc phosphate, sodium zincate, and potassium zincate. .

The aqueous organic resin that can be appropriately blended in the aqueous metal surface treatment agent of the present invention includes an organic resin that can be stably dissolved or dispersed in the aqueous metal surface treatment agent of the present invention. Specifically, A nonionic or anionic organic resin containing a functional group (for example, an acid group such as a hydroxyl group, a polyoxyalkylene group, or a carboxyl group) that can be water-soluble or water-dispersed singly or with a basic compound An organic resin emulsion emulsified with a nonionic surfactant (emulsifier). Examples of the resin type of the aqueous organic resin include epoxy resins, phenol resins, acrylic resins, urethane resins, olefin-carboxylic acid resins, polyamide resins, resins having a polyoxyalkylene chain, polyvinyl alcohol, Examples include polyglycerin and cellulose resins (for example, carboxymethyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose). These aqueous organic resins can be used alone or in combination of two or more. Among these, an acrylic resin emulsion or a urethane resin emulsion is preferable from the viewpoint of the balance between the storage stability of the metal surface treatment agent and the surface treatment agent film performance. By blending an aqueous organic resin with the aqueous metal surface treating agent of the present invention, the wettability to the substrate and the corrosion resistance may be improved. In the case of blending, the blending amount of the aqueous organic resin is usually 20% by mass or less, preferably 0.5%, based on the total solid content of the surface treating agent, from the viewpoint of the conductivity and corrosion resistance of the surface treating agent film to be obtained. It is preferable to be in the range of ˜10% by mass.

The aqueous metal surface treatment agent of the present invention preferably has a pH generally in the range of 2 to 11, particularly 7 to 10, and more particularly 8.0 to 9.5. If the pH of the treatment liquid is less than 2, the storage stability of the surface treatment agent tends to be reduced, and the metal material that is the material is significantly dissolved, and the surface treatment is formed on the surface of the metal material such as a zinc-based plated steel sheet. The corrosion resistance of the agent film and the adhesion to the metal material surface are likely to be lowered. On the other hand, when pH exceeds 11, etching of metal materials, such as a galvanized steel plate, becomes remarkable, and corrosion resistance and electroconductivity of metal materials, such as a galvanized steel plate, fall. In the present invention, the pH can be adjusted by adding an alkali or an acid to the aqueous metal surface treatment agent. Examples of the alkali used include ammonia, amines, amine derivatives and aminopolycarboxylic acids, hydroxylation. Examples of the acid include organic acids such as formic acid, acetic acid, lactic acid and tartaric acid; inorganic acids such as hydrochloric acid, nitric acid, sulfuric acid and phosphoric acid; and the phosphoric acid compound (d) And the like.

The solid content concentration of the aqueous metal surface treatment agent of the present invention is not particularly limited and can be changed according to the application, etc., but the viscosity of the metal surface treatment agent, the surface treatment agent film obtained by coating, From the viewpoint of adhesion amount, flowability, paintability, etc., it is usually preferably in the range of 3 to 35% by mass, particularly 4 to 30% by mass, and more particularly 5 to 25% by mass.

The coating amount of the aqueous metal surface treatment agent of the present invention is preferably within the range of 0.05 to 1.5 g / m ² in terms of the dry surface treatment agent film mass adhering to the metal material surface. .

Surface treatment method of metal material The aqueous metal surface treatment agent of the present invention is coated on the surface of a metal material where it is desired to impart corrosion resistance, etc., and then dried, so that the surface of the metal material is treated with an aqueous metal surface treatment agent. An agent film can be formed.

The metal material to which the aqueous metal surface treatment agent of the present invention can be applied is not particularly limited. For example, iron, iron-base alloy, aluminum, aluminum-base alloy, copper, copper-base alloy, metal material top In particular, a zinc-plated steel sheet can be most suitably applied as the metal material. Examples of galvanized steel sheets include galvanized steel sheets; zinc-nickel plated steel sheets, zinc-iron plated steel sheets, zinc-chromium plated steel sheets, zinc-aluminum plated steel sheets, zinc-titanium plated steel sheets, zinc-magnesium plated steel sheets, zinc -Manganese-plated steel sheets, zinc-aluminum-magnesium-plated steel sheets, zinc-aluminum-magnesium-silicon-plated steel sheets, etc .; and zinc-plated steel sheets such as zinc-aluminum-magnesium-silicon-plated steel sheets; Examples include those containing nickel, titanium, chromium, aluminum, manganese, iron, magnesium, lead, bismuth, antimony, tin, copper, cadmium, arsenic, etc., and those dispersed with inorganic substances such as silica, alumina, titania, etc. it can. Furthermore, what gave the multilayer plating which combined 2 or more types of the above plating can also be used. The plating method is not particularly limited, and any known plating method such as electroplating method, hot dipping method, vapor deposition plating method, dispersion plating method, vacuum plating method, etc. may be used. Good.

The coating of the aqueous metal surface treatment agent of the present invention on the surface of a metal material can be carried out by a coating method known per se, for example, a method such as dip coating, spray coating or roll coating. Before applying the metal surface treatment agent, the surface of the metal material is subjected to pretreatment such as hot water washing, solvent washing, alkaline degreasing washing, etc. for the purpose of removing oil and dirt on the metal material surface, if necessary. Can be applied.

The drying of the surface treatment agent film can be performed by drying for about 2 seconds to about 30 seconds at a material arrival temperature of usually about 50 to about 250 ° C., particularly about 80 to about 200 ° C.

The adhesion amount of the surface treatment agent film on the surface of the metal material is generally from 0.05 to 5 in terms of dry film mass from the viewpoint of the corrosion resistance, adhesion, conductivity, etc. of the film on the metal material surface on which the surface treatment agent film is formed. It is preferable to be within the range of 1.5 g / m ² , particularly 0.1 to 1.0 g / m ² , more particularly 0.2 to 0.7 g / m ² .

Surface-treated metal material The surface-treated metal material according to the present invention can be obtained by the above-mentioned metal material surface treatment method.
The surface treatment agent film adhered to the surface of the metal material according to the present invention can be excellent in corrosion resistance, adhesion, and conductivity, and can have a good film appearance.

The reason is presumed as follows, but the present invention is not restricted to this presumption. The film formed using the aqueous metal surface treatment agent used in the present invention has a binder component mainly composed of an organosilicon compound, and when the organosilicon compound is concentrated by drying or the like, the organosilicon The alkoxysilyl group of the compound reacts with a hydrolyzed silanol group and the like to form a continuous film; the silanol group crosslinks with a zirconium compound or a titanium compound, and is a silane which is one component of the organosilicon compound The coupling agent has an epoxy group or an amino group, and the epoxy group undergoes a crosslinking reaction with a silanol group, a zirconium compound or a titanium compound, or the amino group is a zirconium compound or a titanium compound, a base metal surface or an epoxy group. In addition, the silanol groups produced by hydrolysis are bonded to the metal surface. Forming a, etc. is considered, by these interactions, it is presumed that remarkable barrier effect. In addition, a dense surface treatment agent film can be formed, the film can be thinned, and a surface-treated metal material having good conductivity can be obtained.

In addition, the vanadium compound exists uniformly dispersed in the film, and exhibits an inhibitory effect on metal corrosion. That is, it is presumed that the vanadium compound is partially ionized and passivated in a corrosive environment to suppress corrosion of metals such as zinc. Moreover, it is estimated that a phosphoric acid compound has the effect which suppresses that a tetraalkoxysilane and its low condensate polymerize in a surface treating agent, and dissolves a vanadium compound etc. stably.

That is, the surface-treated metal material of the present invention includes a binder component containing a tetraalkoxysilane (low condensate) and a specific silane coupling agent, a vanadium compound, a corrosion inhibitor such as a zirconium compound or a titanium compound, and a phosphate compound. As a result, due to the interaction of these components, even if the formed film is a thin film, it can have high corrosion resistance and can maintain excellent electrical conductivity. Conceivable.

By using the aqueous metal surface treatment agent of the present invention, the surface-treated metal material such as a zinc-based plated steel sheet having excellent corrosion resistance, adhesion, and various performances, in particular, without lowering the corrosion resistance. Can be provided. Surface-treated metal materials such as galvanized steel sheets coated with the aqueous metal surface treatment agent of the present invention can be applied to various applications, for example, used in various fields such as architecture, electricity, and automobiles. It can be suitably used as a metal material.

Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples, but the scope of the present invention is not limited to these examples. Hereinafter, “parts” and “%” represent “parts by mass” and “% by mass” unless otherwise specified.

Production Examples 1 to 20: Production of Binder Component (A) In deionized water, component (a), component (b) and component (c) were mixed in the composition shown in Table 1 below, and in the presence of an acid catalyst. A hydrolysis reaction was performed to obtain a uniform aqueous solution of binders A1 to A20 having an active ingredient content of 20% excluding the solvent. Production Examples 18 to 20 (A18 to A20) are for comparison. Table 1 below also shows the weight average molecular weight of the obtained binder component. The weight average molecular weight was determined by the following GPC measurement method based on polystyrene. Moreover, the following ²⁹ Si NMR confirmed the reduction | decrease of each raw material and the production | generation of a hydrolysis-condensation product.

GPC measurement method: “HLC-8120GPC” (trade name, manufactured by Tosoh Corporation) is used as a gel permeation chromatograph, and “TSKgel G4000HXL”, “TSKgel G3000HXL”, “TSKgel G2500HXL” and “TSKgel G2000HXL” are used as columns. (Trade name, all manufactured by Tosoh Corporation), using a differential refractometer as the detector, mobile phase: tetrahydrofuran, measurement temperature: 40 ° C., flow rate: 1 mL / min The retention time (retention capacity) is obtained by measuring at. The obtained retention time (retention capacity) is compared with the retention time (retention capacity) of standard polystyrene having a known molecular weight measured under the same conditions, and converted to the molecular weight of polystyrene to determine the weight average molecular weight.

²⁹ Si NMR measurement method: FT-NMR EX-400 (trade name, manufactured by JEOL) is used, and measurement is performed using heavy water as a solvent and tetramethylsilane as an internal standard substance. For the silane coupling agent, a signal around −55 to −35 ppm, and for a tetraalkoxysilane, a signal around −100 to −80 ppm, respectively, the reduction of the alkoxy group derived from the raw material and the formation of hydrolysis condensate, respectively. It was confirmed.

Each symbol in the column of the type of component (a), component (b), and component (c) in Table 1 has the following meaning.
Ingredient (a)
a1: Tetraethoxysilane a2: Tetramethoxysilane a3: Tetraethoxysilane low condensate (average condensation degree 2)
a4: Tetraethoxysilane low condensate (average condensation degree 5)
Ingredient (b)
b1: γ-glycidoxypropyltrimethoxysilane b2: γ-glycidoxypropyltriethoxysilane b3: γ-glycidoxypropylmethyldiethoxysilane b4: 3-aminopropyltriethoxysilane b5: N- (aminoethyl) ) 3-Aminopropyltrimethoxysilane
Ingredient (c)
c1: Triethoxyethylsilane c2: Trimethoxypropylsilane c3: Dimethoxydiethylsilane c4: Trimethoxypropylsilane low condensate (average condensation degree 2)

Examples 1 to 44 and Comparative Examples 1 to 12: Production of aqueous metal surface treatment agent In deionized water, the binder and the components (d), (e) and (f) and other additive components are shown in Table 2 below. And the pH was adjusted to obtain 1 kg of a metal surface treatment agent. The amount of each component in Table 2 is the amount of the binder and the components (d), (e) and (f) below and other additive components blended to obtain 1 kg of the metal surface treatment agent (g) Indicates. The binders A1 to A20 obtained in Production Examples 1 to 20 have an active ingredient content of 20% and are indicated by the active ingredient amount. About the said components other than a binder, it displays by solid content. About the compounding quantity of (f) component, the mass ratio (f) / (a) of Zr conversion mass of (f) component and (a) component which comprises a part of binder is also displayed. The pH of the metal surface treatment agent was adjusted using acetic acid or N, N-dimethylaminoethanol. In addition, Table 2 also shows the storage stability test results of each metal surface treatment agent. The storage stability was evaluated according to the following method.

Storage stability: After each surface treatment agent is stored in a constant temperature bath at 40 ° C. for 30 days, the appearance of the surface treatment agent is visually observed and evaluated according to the following criteria.
◎: No change ○: Slight precipitation is observed Δ: Considerable precipitation is observed, or considerable increase in viscosity is observed ×: Massive precipitation is observed, or gelation occurs.

The composition of the binders A21 to A40 described in Table 2 above (mixing ratios per 100 parts by mass of components (a), (b), and (c)) is as shown in Table 3 below.

Moreover, each symbol in the column of the type of the component (d), the component (e) and the component (f) in Table 2 and the column of the type of the other additive component have the following meanings.
(D) component d1: 1-hydroxyethane-1,1-diphosphonic acid,
d2: 1-hydroxymethane-1,1-diphosphonic acid,
d3: orthophosphoric acid,
(E) Component e1: ammonium metavanadate [NH ₄ VO ₃ ],
e2: sodium metavanadate [NaVO ₃ ],
(F) Component f1: Zirconyl ammonium carbonate [(NH ₄ ) ₂ ZrO (CO ₃ ) ₂ ],
f2: sodium zirconyl carbonate [Na ₂ ZrO (CO ₃ ) ₂ ],
Other additive component h1: Titanium ammonium fluoride [(NH ₄ ) ₂ TiF ₆ ]
h2: aluminum nitrate Kyumizushio _{_{[Al (NO 3) 3 · 9}} (H 2 O) ]
j: Polyethylene wax (Mitsui Chemicals, trade name “Chemipearl W-700”),
k: Acrylic resin emulsion (trade name “Yodosol AD123” manufactured by Henkel Japan K.K.).

Example 45
To an electrogalvanized steel sheet (hereinafter sometimes abbreviated as “EG”) having a plate thickness of 0.8 mm and a weight per unit area of 20/20 (g / m ² ), an alkaline degreasing agent (trade name “Nippon CB Chemical Co., Ltd. A 2% concentration aqueous solution in which Chemicleaner 561B ") was dissolved was degreased by spraying it at 60 ° C for 2 minutes, washed with water, dried, and then obtained on the surface of this steel plate in Example 1 above. The metal surface treatment agent was applied with a roll coater, and baked for 20 seconds so that the material arrival temperature was 100 ° C., to obtain a surface treatment plate having a surface treatment agent film adhesion amount of 0.4 g / m ² .

Examples 46 to 98 and Comparative Examples 13 to 24
In the above Example 45, according to the specifications shown in Table 4 below, the same operation as in Example 45 was performed except that each metal surface treatment agent was coated and baked on each degreased steel plate to obtain each surface-treated plate. It was.

In Table 4, each abbreviation described in the column of the type of metal substrate has the following meaning. In addition, the plating weight per unit area displays the amount per unit area of the front surface and the back surface.
EG: plate thickness 0.8mm and electro-galvanized steel sheet GI plating unit weight 20/20 (g / ^{m 2):} sheet thickness 0.8mm and galvanized steel sheet plated basis weight 60/60 (g / ^{m 2)} GA: iron-zinc alloyed hot-dip galvanized steel sheet GL: plate thickness 0.8 mm and plating weight 40/40 (g / m ² ): plate thickness 0.8 mm and plating weight 60/60 (g / m ² ) Aluminum-zinc alloy-plated steel sheet, containing about 55% aluminum in the alloy.

About each obtained surface treatment board, the performance test was done according to the following test method. The test results are also shown in Table 4 below.

〔Test method〕
Paintability (appearance of coating film): Each surface-treated plate is visually observed and evaluated according to the following criteria.
a: No unevenness is observed at all, and the entire surface has a uniform hue. b: A slight iridescent unevenness is observed, but there is no practical problem. c: A considerable amount of iridescent unevenness is observed. There are practical problems.

Corrosion resistance test (initial corrosion resistance and corrosion resistance after degreasing):
Initial corrosion resistance is evaluated by the following salt spray test about each obtained surface treatment board.

Corrosion resistance after degreasing is determined by adding an aqueous solution having a concentration of 2% in which an alkaline degreasing agent (trade name “Palclean CL-N364S”, manufactured by Nihon Parkerizing Co., Ltd.) is dissolved to each surface-treated plate at a temperature of 60 ° C. for 2 minutes. The surface treatment plate after degreasing, washing with water and drying by spraying is evaluated by the following salt spray test.

(Salt water spray test) The end face part and the back surface part of each surface treatment plate are sealed, and by the salt water spray test (SST) according to JIS Z 2371, the occurrence of rust at the test time of 120 hours and 240 hours is visually observed, Evaluation is based on the following criteria.
a: Rust generation is not observed b: Rust generation is less than 5% of the total area c: Rust generation is 5% or more and less than 10% of the total area d: Rust generation is 10% or more and 50% of the total area Less than e: Rust generation is 50% or more of the total area.

Adhesion test: The surface treatment agent film surface of each surface treatment plate was cut with a grid so that 100 squares of 1 mm × 1 mm were formed in 10 mm square so as to reach the substrate with a cutter knife. After performing the Erichsen test (7 mm extrusion) so that the grid part is pushed outward, the cellophane adhesive tape is brought into close contact with the extruded processed part, and instantly peeled off to remove the surface treatment agent film. The degree is evaluated according to the following criteria.
A: No peeling of the surface treatment agent film is observed. X: Peeling of the surface treatment agent film is observed.

Conductivity test: Using a conductivity measuring device (Mitsubishi Chemical Analytech Co., Ltd., Loresta GP, ASP terminal), measure the surface resistance value at any 10 locations on the surface-treated plate and measure 10 ⁻⁴ Ω or less. Evaluate by the number of times indicated.
a: All 10 times b: 6-9 times c: 1-5 times d: 0 times.

As is apparent from the above test results, the aqueous metal surface treatment agent of the present invention is excellent in paintability and storage stability, and the treatment agent film formed from the aqueous metal surface treatment agent of the present invention has a coating film appearance, Satisfies all of corrosion resistance, adhesion and conductivity.

Examples 99 to 142 and Comparative Examples 25 to 36: Production of aqueous metal surface treatment agent In deionized water, binders, components (d), (e) and (f ′) and other additive components are shown in Table 5 below. The composition was mixed and the pH was adjusted to obtain 1 kg of a metal surface treatment agent. The amount of each component in Table 5 is the amount of the binder and the following components (d), (e) and (f ′) and other additive components blended to obtain 1 kg of the metal surface treatment agent (g ). The binders A1 to A20 obtained in Production Examples 1 to 20 have an active ingredient content of 20% and are indicated by the active ingredient amount. About the said components other than a binder, it displays by solid content. The pH of the metal surface treatment agent was adjusted using acetic acid or N, N-dimethylaminoethanol. Table 5 also shows the storage stability test results for each metal surface treatment agent. The storage stability was evaluated according to the same method as in Table 2 above.

The compositions of the binders A21 to A40 described in Table 5 above (mixing ratios per 100 parts by mass of the components (a), (b), and (c)) are as shown in Table 3 above.
In addition, each symbol in the column of (d) component, (e) component, and other additive components in Table 5 has the same meaning as in Table 2, and (f ′) in the column of component types. Each symbol represents the following meaning.
(F ′) component f′1: titanium ammonium fluoride [(NH ₄ ) ₂ TiF ₆ ],
f′2: fluorinated titanic acid [H ₂ TiF ₆ ].

Example 143
Concentration 2 in which an alkaline degreasing agent (trade name “Chem Cleaner 561B” manufactured by Nippon CB Chemical Co., Ltd.) was dissolved in an electrogalvanized steel sheet (EG) having a thickness of 0.8 mm and a basis weight of 20/20 (g / m ² ). % Of the aqueous solution was degreased by spraying at 60 ° C. for 2 minutes, washed with water, and dried, and then the metal surface treatment agent obtained in Example 99 was applied to the surface of the steel sheet using a roll coater. It was coated and baked for 20 seconds so that the material arrival temperature was 100 ° C., to obtain a surface-treated plate having a surface treatment agent film adhesion amount of 0.4 g / m ² .

Examples 144 to 196 and Comparative Examples 37 to 48
In Example 143, in accordance with the specifications shown in Table 6 below, each metal surface treatment agent was applied to each degreased steel plate and baked except that the surface treatment plate was obtained. It was.

In Table 6, each abbreviation described in the column of the type of metal base has the same meaning as in Table 4.
About each obtained surface treatment board, the performance test was done based on the same test method as the said Table 4. The test results are shown in Table 6 below.

Claims

(A) 30 to 70 parts by mass of at least one tetraalkoxysilane and tetraalkoxysilane low condensate;
(B) 30 to 70 parts by mass of at least one silane coupling agent selected from an epoxy group-containing silane coupling agent and an amino group-containing silane coupling agent;
(C) at least one mono-, di- or tri-alkoxysilane and / or at least one low-condensate mono-, di- or tri-alkoxysilane 0 to 40 parts by weight of mixture (I) or mixture A binder component (A) comprising a hydrolysis condensate (II) obtained by subjecting (I) to a hydrolysis condensation reaction,
(D) a phosphoric acid compound,
An aqueous metal surface treatment agent comprising (e) a vanadium compound, and (f) a zirconium compound or (f ′) a titanium compound,
Per 100 parts by weight of the total of the components (a), (b) and (c),
2-60 parts by mass of the phosphoric acid compound (d) and 1-50 parts by mass of the vanadium compound (e), and the zirconium compound (f), the Zr equivalent mass of the component (f) and the above (a) The mass ratio (f) / (a) with the component is 0.02 or more and less than 1.0, or the titanium compound (f ′) is added in the above (a), (b) and ( c) An aqueous metal surface-treating agent characterized by containing 0.1 to 100 parts by mass per 100 parts by mass of total components.
The binder component (A) is composed of 40 to 60 parts by mass of the component (a), 40 to 60 parts by mass of the component (b), and 100 parts by mass per 100 parts by mass of the components (a), (b) and (c). The aqueous metal surface treatment agent according to claim 1, comprising a mixture of 0 to 20 parts by mass of a component or a hydrolysis condensate obtained by subjecting the mixture to a hydrolysis condensation reaction.
The aqueous metal surface treatment agent according to claim 1 or 2, wherein the binder component (A) is a hydrolysis condensate (II).
The aqueous metal surface treatment agent according to any one of claims 1 to 3, wherein the phosphoric acid compound (d) is 1-hydroxyethane-1,1-diphosphonic acid.
The aqueous metal surface treatment agent according to any one of claims 1 to 4, wherein the vanadium compound (e) is ammonium metavanadate.
The zirconium compound (f) is zirconyl ammonium carbonate [(NH 4 ) 2 ZrO (CO 3 ) 2 ] or sodium zirconyl carbonate [Na 2 ZrO (CO 3 ) 2 ], according to any one of claims 1 to 5. Aqueous metal surface treatment agent.
The aqueous metal surface treating agent according to any one of claims 1 to 6, wherein the titanium compound (f ') is titanium hydrofluoric acid (H 2 TiF 6 ) or titanium ammonium fluoride [(NH 4 ) 2 TiF 6 ]. .
The phosphoric acid compound (d) is contained in an amount of 10 to 35 parts by mass and the vanadium compound (e) is contained in an amount of 5 to 20 parts by mass per 100 parts by mass in total of the components (a), (b) and (c). The aqueous metal surface treating agent according to any one of the above.
The zirconium compound (f) is contained in an amount such that the mass ratio (f) / (a) between the Zr-converted mass of the component (f) and the component (a) is within the range of 0.10 to 0.50. The aqueous metal surface treatment agent according to any one of claims 1 to 8.
The aqueous metal according to any one of claims 1 to 9, comprising 5 to 30 parts by mass of the titanium compound (f ') per 100 parts by mass in total of the components (a), (b) and (c). Surface treatment agent.
The aqueous metal surface treatment agent according to any one of claims 1 to 10, further comprising an aqueous organic resin and / or a wax.
The aqueous metal surface treatment agent according to any one of claims 1 to 11, which has a pH within a range of 2 to 11.
The aqueous metal surface treatment agent according to any one of claims 1 to 12 is coated on the surface of the metal material so that the dry film mass is 0.05 to 1.5 g / m 2 and dried. A surface treatment method of a metal material characterized by the above.
The surface treatment method according to claim 13, wherein the metal material is a zinc-based plated steel sheet.
A surface on which a film made of the aqueous metal surface treatment agent according to any one of claims 1 to 12 is adhered on a surface of a metal material in an amount of 0.05 to 1.5 g / m 2 by dry film mass. Processing metal material.