JP2011137222A - Composition for treating metal surface, and metal substrate having surface-treating film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composition for treating a metal surface, which is superior in storage properties and can form a surface-treating film that is superior in corrosion resistance and also in adhesiveness to a paint film to be formed in a subsequent painting process, and to provide a metal substrate having the surface-treating film. <P>SOLUTION: The composition for treating the metal surface includes the following components (A) to (C), wherein (A) is a titanium-containing aqueous liquid obtained by mixing at least one titanium compound selected from the group consisting of a hydrolyzable titanium compound, a condensate of a hydrolyzable titanium compound, titanium hydroxide and a condensate of titanium hydroxide with hydrogen peroxide water; (B) is an organophosphate compound; and (C) is a condensation product of aminosilane (c1) and a silane compound having multiple silyl functional groups (c2). <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a metal surface treatment composition and a metal substrate having a surface treatment film.

  Conventionally, chromate treatment and phosphate treatment are generally performed as surface treatments in order to improve the corrosion resistance of metal surfaces. However, in recent years, the toxicity of chromium has become a social problem. The surface treatment method using chromate is the problem of scattering of chromate fume in the treatment process, the wastewater treatment equipment is expensive, and the problem of elution of chromic acid from the chemical conversion treatment film, etc. There is. In addition, hexavalent chromium compounds are extremely harmful substances because many public institutions, including IARC (International Agency for Research on Cancer Review), have designated them as carcinogenic substances for the human body.

  Moreover, in order to improve the corrosion resistance of the metal surface, phosphate treatment, for example, zinc phosphate-based and iron phosphate-based surface treatment is performed. In phosphate-based surface treatment, rinsing treatment with chromic acid is generally performed after the treatment with phosphate for the purpose of imparting corrosion resistance. Therefore, in addition to the problem of chromium treatment, there are problems such as a reaction accelerator in the phosphate treatment agent, wastewater treatment of metal ions, sludge treatment by elution of metal ions from the metal to be treated, and the like.

  Zirconium-based and titanium-based surface treatment agents are well known as surface treatment methods other than chromate treatment and phosphate treatment (see Patent Documents 1 to 5, etc.), and are practically used mainly in aluminum-based materials. Has been. However, these treatment agents have a problem that the stability of the treatment agent is insufficient, and that the metal base material such as a galvanized steel sheet is inferior in corrosion resistance as compared with the conventional chromate treatment.

In the patent document 6, the present applicant can not only form a surface treatment film excellent in corrosion resistance but also a treatment agent excellent in storage stability, selected from the group consisting of a specific titanium-containing aqueous liquid and organic acids and salts thereof. A titanium oxide film-forming coating agent containing at least one kind of compound has been proposed.
However, although the above coating agent can form a surface-treated film with excellent storage stability and excellent corrosion resistance, the adhesion with a coating film formed by a subsequent coating process may be insufficient depending on the type of paint. there were.

Japanese Patent Publication No. 48-24618 JP 54-24232 A JP 54-160527 A JP-A-9-20984 Japanese Patent Laid-Open No. 9-143752 International Publication No. 2003/037996

  An object of the present invention is to provide a metal surface treatment composition capable of forming a surface treatment film having excellent storage properties, excellent corrosion resistance, and excellent adhesion to a film formed by a subsequent coating process, and surface treatment. The object is to provide a metal substrate having a coating.

  As a result of intensive studies to achieve the above object, the present inventors have found that the following components (A) to (C), (A) hydrolyzable titanium compound, condensate of hydrolyzable titanium compound, hydroxylation Titanium-containing aqueous liquid obtained by mixing at least one titanium compound selected from the group consisting of titanium and titanium hydroxide condensates with hydrogen peroxide water, (B) an organic phosphate compound, and (C) The present inventors have found that the object can be achieved by a metal surface treatment composition characterized by containing a condensation product of aminosilane (c1) and polysilyl functional silane (c2), and have completed the present invention.

Specifically, the present invention relates to the following aspects.
[Aspect 1]
The following components (A) to (C),
(A) Mixing at least one titanium compound selected from the group consisting of a hydrolyzable titanium compound, a hydrolyzable titanium compound condensate, titanium hydroxide and a titanium hydroxide condensate with a hydrogen peroxide solution. A titanium-containing aqueous liquid obtained by
(B) an organophosphate compound, and (C) a condensation product of aminosilane (c1) and polysilyl functional silane (c2),
A metal surface treatment composition comprising:

[Aspect 2]
The composition for metal surface treatment according to aspect 1, wherein the component (B) is an organic phosphonic acid having a hydroxyl group-containing organic group.
[Aspect 3]
The metal surface treatment composition according to embodiment 1 or 2, wherein the component (B) is 1-hydroxymethane-1,1-diphosphonic acid and / or 1-hydroxyethane-1,1-diphosphonic acid.

[Aspect 4]
Any one of Embodiments 1 to 3 in which the content of the component (B) is in the range of 1 to 400 parts by mass with respect to 100 parts by mass of the converted TiO ₂ content in the component (A). The metal surface treatment composition as described in 1.
[Aspect 5]
The polysilyl functional silane (c2) is represented by the following general formula (I):
_{^{(X 1) 3-ab (}} R 1) a (R 2) b Si-Y-Si (R 3) c (R 4) d (X 2) 3-cd (I)
(Where
R ¹ , R ² , R ³ and R ⁴ independently represent a hydrogen atom or a monovalent organic group having 1 to 30 carbon atoms,
Y represents a divalent organic group or imino group,
X ¹ and X ² independently represent a hydrolyzable group,
a and b are independently 0, 1, or 2, but 0 ≦ a + b ≦ 2, and c and d are independently 0, 1, or 2, but 0 ≦ c + d ≦ 2. )
The composition for metal surface treatment as described in any one of Embodiments 1-4 shown by these.

[Aspect 6]
The component (C) is produced by condensing the aminosilane (c1) and the polysilyl functional silane (c2) at a molar ratio of 50/50 to 99/1, according to any one of embodiments 1 to 5. Metal surface treatment composition.
[Aspect 7]
Any one of Embodiments 1 to 6, wherein the content of the component (C) is in the range of 1 to 400 parts by mass with respect to 100 parts by mass of the converted TiO _{2 in} the component (A). The metal surface treatment composition as described in 1.

[Aspect 8]
A metal substrate having a surface treatment film formed by coating a metal substrate with the composition for metal surface treatment according to any one of Embodiments 1 to 7, and then drying.
[Aspect 9]
The metal substrate which has a surface treatment film of the aspect 8 whose basic weight of the said surface treatment film exists in the range of 0.001-10 g / m < ² >.

  The metal surface treatment composition of the present invention can form a surface-treated film that is excellent in storability, excellent in corrosion resistance, and excellent in adhesion to coating films formed by various paints formed by a subsequent coating process.

<Composition for metal surface treatment>
In the metal surface treatment composition of the present invention, at least one titanium compound selected from a hydrolyzable titanium compound, a hydrolyzable titanium compound condensate, titanium hydroxide and a titanium hydroxide condensate is added with hydrogen peroxide. Examples of the titanium-containing aqueous liquid obtained by mixing with (hereinafter, may be simply referred to as “component (A)”) include known ones.

  The hydrolyzable titanium compound is a titanium compound having a hydrolyzable group directly bonded to a titanium atom, and generates titanium hydroxide by reacting with water such as water or water vapor. In the hydrolyzable titanium compound, a part of the hydrolyzable group may be hydrolyzed to be a hydroxyl group.

  The hydrolyzable group is not particularly limited as long as it generates a hydroxyl group by reacting with moisture, and examples thereof include a lower alkoxyl group and a group that forms a salt with a titanium atom. Examples of the group that forms a salt with a titanium atom include a halogen atom (such as chlorine), a hydrogen atom, and a sulfate ion.

Examples of the hydrolyzable titanium compound containing a lower alkoxyl group as the hydrolyzable group include tetraalkoxy titanium.
Typical examples of the hydrolyzable titanium compound having a group capable of forming a salt with titanium as a hydrolyzable group include titanium chloride and titanium sulfate.

The condensate of hydrolyzable titanium compounds is a condensate of the hydrolyzable titanium compounds. In the condensate, a part of the hydrolyzable group bonded to the titanium atom may be hydrolyzed to become a hydroxyl group.
Examples of the titanium hydroxide condensate include orthotitanic acid (titanium hydroxide gel) obtained by reacting an aqueous solution such as titanium chloride and titanium sulfate with an alkaline aqueous solution such as ammonia and caustic soda.

  The condensation degree in the hydrolyzable titanium compound condensate or titanium hydroxide condensate is preferably in the range of about 2 to about 30, and more preferably in the range of about 2 to about 10. preferable.

In particular, the component (A) is preferably a peroxotitanic acid aqueous solution (a ₁ ) obtained by mixing a hydrolyzable titanium compound and / or a condensate thereof with a hydrogen peroxide solution.

As the titanium compound, in particular, the following general formula (1):
Ti (OR) ₄ (1)
(In formula, R is the same or different and shows a C1-C5 alkyl group.)
The tetraalkoxy titanium represented by these is preferable.
Examples of R include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group.

  Further, the condensate of the titanium compound is preferably a condensate having a degree of condensation of about 2 to about 30 produced by causing the compounds of the general formula (1) to undergo a condensation reaction with each other. More preferred is a condensate of 2 to about 10.

  In order to obtain the compound (A), the hydrolyzable titanium compound of the general formula (1) and / or its condensate (hereinafter referred to as “the hydrolyzable titanium compound of the general formula (1) and / or its condensate” The ratio of mixing the hydrogen peroxide solution with the hydrogen peroxide solution may be about 0% with respect to 10 parts by mass of the hydrolyzable titanium compound (T). The ratio is preferably from about 1 to about 100 parts by weight, and particularly preferably from about 1 to about 20 parts by weight. When the hydrogen peroxide solution is less than about 0.1 parts by mass in terms of hydrogen peroxide, the production of peroxotitanic acid may be insufficient and white turbid precipitation may occur. On the other hand, when the amount of hydrogen peroxide exceeds about 100 parts by mass in terms of hydrogen peroxide, unreacted hydrogen peroxide tends to remain, and dangerous active oxygen may be released during storage.

  The concentration of hydrogen peroxide in the hydrogen peroxide water is not particularly limited, but is preferably in the range of about 3 to about 40% by mass from the viewpoint of ease of handling.

In addition, the aqueous peroxotitanic acid solution (a ₁ ) is usually obtained by stirring the hydrolyzable titanium compound (T) in the range of about 1 to about 70 ° C. for about 10 minutes to about 20 hours with aqueous hydrogen peroxide. It can be prepared by mixing. In mixing, for example, a water-soluble solvent such as methanol, ethanol, n-propanol, isopropanol, ethylene glycol monobutyl ether, propylene glycol monomethyl ether can be added as desired, and the peroxotitanic acid aqueous solution (a ₁ ) In addition to water, a water-soluble solvent may be included.

The peroxotitanic acid aqueous solution (a ₁ ) is obtained by mixing the hydrolyzable titanium compound (T) with hydrogen peroxide water, thereby hydrolyzing the hydrolyzable titanium compound (T) to produce a hydroxyl group-containing titanium compound. Next, it is presumed that hydrogen peroxide immediately coordinates with this hydroxyl group-containing titanium compound to form peroxotitanic acid. The peroxotitanic acid aqueous solution (a ₁ ) has high stability at room temperature and can withstand long-term storage.

  In the metal surface treatment composition of the present invention, the organophosphate compound as the component (B) improves the storage stability of the metal surface treatment composition of the present invention and improves the corrosion resistance of the surface treatment film to be formed. An organic phosphonic acid containing a hydroxyl group-containing organic group, such as 1-hydroxymethane-1,1-diphosphonic acid, 1-hydroxyethane-1,1-diphosphonic acid, 1-hydroxypropane- 1,1-diphosphonic acid, nitrilo (amino) trimethylenephosphonic acid, nitrilo (amino) triethylenephosphonic acid, nitrilo (amino) tripropylenephosphonic acid, ethylenediaminetetramethylenephosphonic acid, ethylenediaminetetraethylenephosphonic acid, ethylenediaminetetrapropylenephosphonic Acid, N, N-bis (2-phosphoethyl) Hydroxyamine, N, N-bis (2-phosphomethyl) hydroxyamine, hydrolyzate of 2-hydroxyethylphosphonic acid dimethyl ether, phosphonic acid having a carboxyl group-containing organic group, such as 2-hydroxyphosphonoacetic acid, 2-phosphonobutane -1,2,4-tricarboxylic acid, and salts thereof.

  From the viewpoint of improving the storage stability of the metal surface treatment composition of the present invention and the corrosion resistance of the surface treatment film to be formed, 1-hydroxymethane-1,1-diphosphonic acid and 1-hydroxyethane are used as the component (B). -1,1-diphosphonic acid is preferred, and 1-hydroxyethane-1,1-diphosphonic acid is particularly preferred.

The content of the component (B) is in the range of about 1 to about 400 parts by weight, preferably about 10 to about 200 parts by weight with respect to 100 parts by weight of the converted TiO _{2 in} the component (A). It is desirable from the viewpoint of the storage stability of the metal surface treatment composition of the present invention and the improvement of the corrosion resistance of the surface treatment film to be formed.
In the present specification, “converted TiO ₂ amount” or “converted TiO ₂ concentration” means that the titanium compound added in the preparation of the component (A) is a composition for metal surface treatment. after formation of the film by the object, based on the assumption that those are present as TiO _2, it means an amount or concentration of TiO ₂ of TiO ₂ obtained by calculation from the amount of titanium of the titanium compound.

  In the metal surface treatment composition of the present invention, a condensation product of (C) aminosilane (c1) and polysilyl functional silane (c2) (hereinafter sometimes referred to as “component (C)”) is formed. It is a component included for improving the corrosion resistance of the surface-treated film and improving the adhesion to the coating film formed by the subsequent coating process. Usually, aminosilane (c1) and polysilyl functional silane (c2) are added to water, It can be obtained by hydrolysis and condensation in alcohol, acidic aqueous solution or the like. When an acid is used for hydrolysis, for example, hydrochloric acid, acetic acid, sulfuric acid, phosphoric acid, sulfonic acid and the like can be used.

  As aminosilane (c1), for example, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropylmethyldiethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N- (2 -Aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltriethoxysilane, and the like.

The polysilyl functional silane (c2) has the following general formula (I):
_{^{(X 1) 3-ab (}} R 1) a (R 2) b Si-Y-Si (R 3) c (R 4) d (X 2) 3-cd (I)
(Where
R ¹ , R ² , R ³ and R ⁴ independently represent a hydrogen atom or a monovalent organic group having 1 to 30 carbon atoms,
Y represents a divalent organic group or imino group,
X ¹ and X ² independently represent a hydrolyzable group,
a and b are independently 0, 1, or 2, but 0 ≦ a + b ≦ 2, and c and d are independently 0, 1, or 2, but 0 ≦ c + d ≦ 2. )
It is preferable to have the structure shown by these.

Examples of monovalent organic groups in R ¹ , R ² , R ³ and R ⁴ include hydrocarbon groups such as alkyl groups, alkenyl groups, cycloalkyl groups, and aryl groups; a hydrocarbon skeleton, hydroxyl groups, epoxy groups, amino groups Examples include a group having a functional group such as a group bonded thereto, and a lower alkyl group such as a methyl group or an ethyl group is particularly preferable.
Examples of the divalent organic group for Y include alkylene groups, alkyleneoxy groups, and alkylenethio groups having 2 to 30 carbon atoms, and more preferably 2 to 12 carbon atoms, and combinations thereof.

Examples of the hydrolyzable group in X ¹ and X ² include an alkoxyl group having 1 to 4 carbon atoms, and a methoxyl group and an ethoxyl group are particularly preferable. Moreover, it is preferable that both a + b and c + d are 0 or 1.

  Specific examples of the polysilyl functional silane (c2) include, for example, bis (trimethoxysilyl) methane, bis (trimethoxysilyl) ethane, 1,2-bis (triethoxysilyl) ethane, 1,2-bis (tri Methoxysilyl) ethane, bis (triethoxysilyl) hexane, bis (trimethoxysilyl) hexane, 1,9-bis (triethoxysilyl) nonane, 1,9-bis (trimethoxysilyl) nonane, 1,8-bis (Triethoxysilyl) octane, bis (trimethoxysilyl) amine, bis (triethoxysilyl) amine, bis (triethoxysilylmethyl) amine, bis (triethoxysilylpropyl) amine, etc. , Improved corrosion resistance of the surface treatment film to be formed, and adhesion to the film formed by the subsequent painting process In view of the above, 1,2-bis (triethoxysilyl) ethane is preferred.

  Component (C) comprises aminosilane (c1) and polysilyl functional silane (c2) from about 50/50 to about 99/1, preferably from about 70/30 to about 99/1, more preferably from about 80/20 to Producing by condensation at a molar ratio in the range of about 95/5 is preferable from the viewpoints of preventing gelation during production, improving the corrosion resistance of the formed surface treatment film, and economical.

  In the production of component (C), in addition to aminosilane (c1) and polysilyl functional silane (c2), organosilane (c3) other than aminosilane (c1) and polysilyl functional silane (c2) is optionally added, A component (C) comprising a condensation product of aminosilane (c1), polysilyl functional silane (c2) and organosilane (c3) can be produced.

  Examples of the organosilane (c3) include methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, vinyltrimethoxysilane, Vinyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloyloxypropylmethyldimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropylmethyldiethoxysilane, 3-methacryloyloxypropyltriethoxysilane, 3 -Acryloyloxypropyltrimethoxysilane, 3-chloropropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropylto Silane and the like.

  The organosilane (c3) can be added within a range that does not decrease the solvent solubility of the component (C) in order to control the precipitation of the component (C), and the aminosilane (c1) and the polysilyl functional silane (c2). ) Is usually about 100 mol% or less, preferably about 50 mol% or less.

In the metal surface treatment composition of the present invention, the content of the component (C) is about 1 to about 400 parts by weight, preferably 100 parts by weight of the converted amount of TiO _{2 in} the component (A). Is preferably in the range of about 5 to about 200 parts by mass from the viewpoint of improving the adhesion with a coating film formed by a subsequent coating step and improving the corrosion resistance of the formed surface treatment film.

  The metal surface treatment composition of the present invention contains components (A) to (C), but the metal surface treatment composition of the present invention is formed by improving the corrosion resistance of the surface treatment film to be formed and by a subsequent coating process. A water-soluble or water-dispersible organic resin can be optionally contained from the viewpoint of improving adhesion to the coated film. Examples of the water-soluble or water-dispersible organic resin include epoxy resin, acrylic resin, polyester resin, polyallylamine resin, polyvinylamine resin, polybutadiene resin, polyurethane resin, polyvinyl alcohol, and ethylene-vinyl acetate resin. Moreover, the composition for metal surface treatment of this invention can contain a melamine resin, a benzoguanamine resin, a urea resin, (block) polyisocyanate, a phenol resin etc. as a water-soluble or water-dispersible organic resin.

  When the metal surface treatment composition of the present invention contains the water-soluble or water-dispersible organic resin, the amount thereof is from the viewpoint of improving adhesion with a coating film formed by a subsequent coating step, etc. It is preferably about 1 to about 20,000 parts by weight, more preferably about 5 to about 10,000 parts by weight, and about 20 to about 5,000 parts by weight with respect to 100 parts by weight of component (A). Is more preferably about 500 to about 2,500 parts by mass.

  In order to improve the acid resistance, alkali resistance, etc. of the coating film, the metal surface treatment composition of the present invention is made of Al, Ca, V, Mn, Co, Fe, Cu, Zn, Zr, Nb, Mo, Ta, Divalent or higher metal ions such as W can be included as desired.

  Furthermore, the metal surface treatment composition of the present invention can contain a basic neutralizing agent such as ammonia, an organic basic compound, an alkali metal hydroxide, or an alkaline earth metal hydroxide, if desired. Examples of the organic basic compound include ethanolamine and triethylamine, and examples of the alkali metal hydroxide include lithium hydroxide, sodium hydroxide, and potassium hydroxide.

  Furthermore, the metal surface treatment composition of the present invention can contain various additives as desired. Examples of the additive include a thickener, a fungicide, a rust inhibitor, a titanium oxide sol, a titanium oxide powder, an extender pigment, a rust preventive pigment, a color pigment, and a surfactant. Examples of the rust inhibitor include tannic acid, phytic acid, benzotriazole, ammonium metavanadate, and ammonium zirconium carbonate. Examples of the extender pigment include mica, talc, silica, fine powder silica, barita, and clay.

The manufacturing method of the composition for metal surface treatment of this invention is not specifically limited, For example, the composition for metal surface treatment of this invention is a component (A), a component (B), and a component (C). , As well as other components as desired, and can be prepared by adjusting the concentration to be preferably about 0.1 to about 50% by weight, more preferably about 0.5 to about 40% by weight. .
In the present specification, the concentration of the metal surface treatment composition, the amount of TiO ₂ which is converted, the amount of solids of component (B), the total amount of the solid content of the component (C), The ratio with respect to the whole quantity of the composition for metal surface treatment is meant.

  The metal substrate having a surface treatment film of the present invention has a surface treatment film formed from the metal surface treatment composition. Specifically, the metal substrate having the surface treatment film is formed by coating the metal substrate with the metal surface treatment composition of the present invention and drying the metal substrate coated with the metal surface treatment composition. It is formed by doing.

The metal substrate is not particularly limited as long as it is a metal. For example, iron, copper, aluminum, tin, zinc, and alloys thereof, steel materials plated with the metal and alloys, and the metals and alloys. For example, vapor-deposited products and the like, and the effect of improving the corrosion resistance of the surface treatment film to be formed is remarkable. Therefore, a steel material plated with zinc or a zinc alloy, particularly a galvanized steel plate or a zinc alloy plated steel plate is preferable.
In this specification, a steel material includes a lump of iron and an iron-containing alloy, a molding, a plate-shaped material, a rod-shaped material, and the like, and a steel plate means a plate-shaped material of iron and an iron-containing alloy.

The metal surface treatment composition of the present invention can be coated on the metal substrate by a known treatment method such as dip coating, spray coating, roll coating and the like.
The surface treatment is performed by drying the metal substrate coated with the metal surface treatment composition for about 2 seconds to about 30 seconds under the condition that the maximum temperature of the metal substrate is usually about 60 to about 250 ° C. A metal substrate having a coating can be formed.

When the surface-treatment film is too thin, the corrosion resistance, while the performance such as water resistance is lowered, too thick, cracks, since problems such as workability is lowered occurs, about 0.001 to about 10 g / m ² Preferably, it has a basis weight in the range of about 0.05 to about 3 g / m ² .

  The metal substrate having a surface-treated film of the present invention is used without particular limitation for applications using conventional surface-treated plates, such as for building materials, home appliances, automobiles, cans, and pre-coated steel sheets. A paint, top coat, etc. are applied as desired. The coating method such as the undercoat paint and the topcoat paint can be selected depending on the application, the shape of the object to be coated, and the like, for example, spray coating, brush coating, electrodeposition coating, roll coating, curtain flow coating and the like. Instead of painting, a film can be laminated on a metal substrate having a surface treatment film.

  A coating layer can be formed on a metal substrate having the surface treatment film by applying a conventionally known paint, or an organic resin coating layer can be formed with an adhesive layer interposed therebetween. it can. The conventionally known paint is not particularly limited, and examples thereof include organic solvent diluted paint, water-based paint, and powder paint.

  Hereinafter, the present invention will be described in more detail with reference to examples. “Part” and “%” indicate “part by mass” and “% by mass”, respectively.

[Preparation of component (A)]
[Preparation Example 1]
A mixture of 10 parts of tetraisopropoxy titanium and 10 parts of isopropanol was dropped into a mixture of 10 parts of 30% hydrogen peroxide and 100 parts of deionized water at 20 ° C. over 1 hour with stirring. Thereafter, the mixture was aged at 25 ° C. for 2 hours to obtain a component (A-1) which was a transparent, yellowish and slightly viscous peroxotitanic acid aqueous solution (a ₁ ). The converted TiO ₂ concentration in the component (A-1) was 2%.

[Preparation Example 2]
A component (A-2) was obtained in the same manner as in Preparation Example 1, except that the same amount of tetra-n-butoxy titanium was used instead of tetraisopropoxy titanium. The converted concentration of TiO _{2 in} the component (A-2) was 2%.

[Preparation Example 3]
A component (A-3) was obtained in the same manner as in Preparation Example 1, except that the same amount of tetraisopropoxytitanium trimer was used instead of tetraisopropoxytitanium. The converted concentration of TiO _{2 in} the component (A-3) was 2%.

[Production of component (C)]
[Production Example 1]
200 g of isopropanol and 200 g of deionized water were charged into a 1 L round bottom flask equipped with a reflux condenser, a thermometer, a nitrogen inlet tube, and a stirrer, and stirring was started. Nitrogen was blown into the gas phase, and 90 g of 3-aminopropyltrimethoxysilane and 10 g of bis (triethoxysilyl) ethane were added at a time while stirring. The mixture was stirred at room temperature for 1 hour, reacted at 60 ° C. for 6 hours, the fraction was removed, and the temperature was raised until the boiling point reached 120 ° C. while replacing isopropanol and water with propylene glycol monomethyl ether. After cooling to 60 ° C., the solution was concentrated by distillation under reduced pressure to obtain 120 g of a solution of the condensation product (C ₁ ) as the component (C). The solid content of the solution of the condensation product (C ₁ ) was 40% and was a colorless transparent viscous liquid. The above solids are the condensation product solution of (C _1), a value obtained by heating 1 hour at 130 ° C..

[Production Examples 2 to 12]
The composition of the raw material except that as shown in Table 1 in the same manner as in Production Example 1, component condensation product as (C) (C ₂₎ a solution of ~ (C _8), and a silane condensation product (C ' ₁ ) to (C ′ ₄ ) solutions were obtained.

[Examples 1-8 and Comparative Examples 1-4]
[Preparation of metal surface treatment composition]
According to the formulation shown in Table 2, a metal surface treatment composition was prepared. Each metal surface treatment composition was prepared with deionized water to a concentration of 5%.
In Table 2, component (B) is 1-hydroxyethane-1,1-diphosphonic acid having a solid content of 60%.

[surface treatment]
As a metal substrate, a commercially available electrogalvanized steel sheet (EG steel sheet, manufactured by Nippon Test Panel Co., Ltd., 70 mm × 150 mm × 0.8 mm, single-sided plating basis weight 20 g / m ² ) (hereinafter sometimes referred to as “EG steel sheet”). And 5000 series aluminum (manufactured by Nippon Test Panel Co., Ltd., 70 mm × 150 mm × 0.8 mm) (hereinafter sometimes referred to as “5000AL”) were surface treated in the following steps.

(1) The metal substrate is degreased by immersing it in a commercially available degreasing solution adjusted to 40 ° C. for 2 minutes, and then washed with tap water for 30 seconds.
(2) The metal surface treatment compositions of Examples 1 to 8 and Comparative Examples 1 to 4 were applied to the metal substrate after water washing, and dried for 20 seconds so that the maximum temperature of the metal substrate was 150 ° C. Then, a metal substrate having a surface treatment film with a basis weight of 0.5 g / m ² is formed.

[Preparation of test plate (1)]
On a metal substrate having a surface treatment film formed from the metal surface treatment compositions of Examples 1 to 8 and Comparative Examples 1 to 4, “Majicron # 1000” (manufactured by Kansai Paint Co., Ltd., acrylic / melamine resin organic) A solvent-diluted paint) was applied by air spray so that the dry film thickness was 30 μm, and dried at 160 ° C. for 30 minutes to prepare a test plate. The obtained test plate was evaluated according to the following evaluation method. The results are shown in Table 3.

[Preparation of test plate (2)]
On the metal substrate having the surface treatment film formed from the metal surface treatment compositions of Examples 1 to 8 and Comparative Examples 1 to 4, “Amilak # 1000” (manufactured by Kansai Paint Co., Ltd., alkyd / melamine resin organic) Solvent-diluted paint) was applied by air spray so that the dry film thickness was 30 μm, dried at 130 ° C. for 30 minutes to prepare a test plate, and evaluated according to the following evaluation method. The results are also shown in Table 3.

[Preparation of test plate (3)]
On a metal substrate having a surface treatment film formed from the metal surface treatment compositions of Examples 1 to 8 and Comparative Examples 1 to 4, “ASIME” (manufactured by Kansai Paint Co., Ltd., polyester / melamine resin organic solvent dilution) The coating material was air spray coated so that the dry film thickness was 30 μm, dried at 140 ° C. for 30 minutes to prepare a test plate, and evaluated according to the following evaluation method. The results are also shown in Table 3.

[Comparative Example 5]
A test plate was prepared in the same manner as in Example 1 except that a commercially available steel plate (substrate: SPCC-SD, manufactured by Nippon Test Panel Co., Ltd.) surface-treated with a zinc phosphate-based metal surface treatment composition was used. (1) to (3) were prepared and evaluated according to the following evaluation method. The results are also shown in Table 3.

[Comparative Example 6]
In the same manner as in Example 1, except that a commercially available aluminum plate surface-treated with a chromate-based metal surface treatment composition (base material: 5000 series aluminum, manufactured by Nippon Test Panel Co., Ltd.) was used, a test plate ( 1) to (3) were prepared and evaluated according to the following evaluation methods. The results are also shown in Table 3.

[Evaluation method]
(* 1) Corrosion resistance 1: a metal substrate having a surface treatment film formed from the compositions for metal surface treatment of Examples 1 to 8 and Comparative Examples 1 to 4, and a zinc phosphate metal surface of Comparative Example 5 The steel plate surface-treated with the treatment composition and the aluminum plate surface-treated with the chromate-based metal surface treatment composition of Comparative Example 6 were subjected to a 120-hour salt spray corrosion test (SST: JIS Z-2371). The salt water temperature was 35 ° C.), and the degree of rust was visually evaluated according to the following criteria.

◎: Rust was generated in less than 5% of the area. ○: Rust was generated in the range of 5% or more and less than 20% of the area. Δ: Rust was generated in the range of 20% or more and less than 30% of the area. Rust occurred in more than 30% of the area

  (* 2) Corrosion resistance 2: X-shaped scratches on the test plates (1) to (3) prepared in Examples 1 to 8 and Comparative Examples 1 to 6 so as to reach the metal substrate with a cutter knife When a salt spray corrosion test (SST: JIS Z-2371 according to JIS Z-2371; salt water temperature: 35 ° C.) is performed for 240 hours, the cellophane tape is adhered to the scratched part, and the cellophane tape is peeled off rapidly. The peeled state of the scratched coating film was observed and evaluated according to the following criteria.

◎: The coating film does not peel ○: The peeling width of the coating film is less than 3 mm △: The peeling width of the coating film is 3 mm or more and less than 5 mm ×: The peeling width of the coating film is 5 mm or more

  (* 3) Adhesiveness: The test plates (1) to (3) prepared in Examples 1 to 8 and Comparative Examples 1 to 6 were immersed in warm water (40 ° C.) for 240 hours. Immediately after pulling up, 11 vertical and horizontal lines that go straight to reach the metal substrate with a cutter knife on the coating surface of the test plate according to JIS K-5400 8.5.2 (1990) cross-cut tape method Each parallel straight line was drawn at 1 mm intervals to create 100 squares of 1 mm × 1 mm. The cellophane tape was adhered to the cells, and then the cellophane tape was abruptly peeled, the degree of cell peeling was observed, and the following criteria were evaluated.

◎: The cells did not peel ○: The cells were peeled 5 or less Δ: The cells were peeled 6 to 10 ×: The cells were peeled 11 or more

Claims (9)

The following components (A) to (C),
(A) Mixing at least one titanium compound selected from the group consisting of a hydrolyzable titanium compound, a hydrolyzable titanium compound condensate, titanium hydroxide and a titanium hydroxide condensate with a hydrogen peroxide solution. A titanium-containing aqueous liquid obtained by
(B) an organophosphate compound, and (C) a condensation product of aminosilane (c1) and polysilyl functional silane (c2),
A metal surface treatment composition comprising:   The metal surface treatment composition according to claim 1, wherein the component (B) is an organic phosphonic acid having a hydroxyl group-containing organic group.   The metal surface treatment composition according to claim 1 or 2, wherein the component (B) is 1-hydroxymethane-1,1-diphosphonic acid and / or 1-hydroxyethane-1,1-diphosphonic acid. The content of component (B), in component (A), relative to the amount 100 parts by weight of TiO ₂ which is converted, in the range of 1 to 400 parts by weight, any one of claims 1 to 3 The composition for metal surface treatment according to Item. The polysilyl functional silane (c2) is represented by the following general formula (I):
_{^{(X 1) 3-ab (}} R 1) a (R 2) b Si-Y-Si (R 3) c (R 4) d (X 2) 3-cd (I)
(Where
R ¹ , R ² , R ³ and R ⁴ independently represent a hydrogen atom or a monovalent organic group having 1 to 30 carbon atoms,
Y represents a divalent organic group or imino group,
X ¹ and X ² independently represent a hydrolyzable group,
a and b are independently 0, 1, or 2, but 0 ≦ a + b ≦ 2, and c and d are independently 0, 1, or 2, but 0 ≦ c + d ≦ 2. )
The composition for metal surface treatment of any one of Claims 1-4 shown by these.   The component (C) is produced by condensing an aminosilane (c1) and a polysilyl functional silane (c2) at a molar ratio of 50/50 to 99/1. The composition for metal surface treatment as described. The content of component (C) is, in component (A), relative to the amount 100 parts by weight of TiO ₂ which is converted, in the range of 1 to 400 parts by weight, any of claims 1 to 6 one The composition for metal surface treatment according to Item.   A metal substrate having a surface-treated film formed by coating the metal substrate with the composition for metal surface treatment according to any one of claims 1 to 7, followed by drying. The metal base material which has a surface treatment film | membrane of Claim 8 which has the basic weight of the said surface treatment film | membrane in the range of 0.001-10 g / m < ² >.