JP5431721B2 - Surface treatment composition for zinc-based plated steel sheet or aluminum-based plated steel sheet and surface-treated steel sheet - Google Patents

Description

  The present invention is a surface treatment composition and a surface-treated steel sheet suitable for use in automobiles, home appliances, and building materials, and uses an environment-adaptive surface treatment composition that does not contain any hexavalent chromium in the composition or coating film. The present invention relates to a surface-treated steel sheet.

  Conventionally, steel sheets for home appliances, steel sheets for building materials, and steel sheets for automobiles have been used for the purpose of improving corrosion resistance (white rust resistance, red rust resistance) on the surface of zinc-plated steel sheets or aluminum-plated steel sheets. Steel plates subjected to chromate treatment with a treatment liquid containing chromic acid or a salt thereof as a main component are widely used. This chromate treatment is an economical treatment method that is excellent in corrosion resistance and can be performed relatively easily.

  The chromate treatment uses hexavalent chromium which is a pollution control substance. This hexavalent chromium is treated in a closed system in the treatment process, and the sealing action by the organic film formed on the upper layer causes the chromate film to contain Since the elution of chromium from can be made almost zero, the human body and the environment are not substantially polluted by hexavalent chromium. However, with increasing interest in global environmental issues in recent years, not only laws and regulations that emphasize the conventional work environment and wastewater treatment, but also laws and regulations that emphasize environmental load and environmental harmony are beginning. In addition, with the background of the times when manufacturers are evaluated by their degree of environmental contribution, there is an increasing trend to reduce the use of heavy metals including hexavalent chromium.

  Under such a background, many white rust suppression techniques (chromate-free techniques) for zinc-based plated steel sheets that do not use hexavalent chromium have been proposed. For example, Patent Documents 1 and 2 propose a surface treatment agent containing Al, a phosphoric acid compound, silica, and a water-based organic resin emulsion, and a metal material coated therewith. Patent Document 3 proposes a galvanized steel sheet in which an organic coating layer is formed after an amorphous film is formed by applying and drying a mixed aqueous solution of polyphosphate primary phosphate and metal oxide sol. Has been. Further, in Patent Documents 4 and 5, a composite oxide film layer containing oxide fine particles, phosphoric acid and / or a phosphoric acid compound, and one or more metals selected from Mg, Mn, and Al is used as a lower layer. A steel sheet having an organic film formed thereon is proposed.

Japanese Patent Laid-Open No. 11-350157 JP 2000-26980 A JP 2000-129460 A JP 2002-53979 A JP 2002-53980 A

  Among the applications to which galvanized steel sheets are applied, there are not a few parts that are heated in a temperature range (about 500 to 600 ° C.) above the melting point of zinc. For example, in a heat exchanger in an air conditioner outdoor unit, when brazing a copper pipe and an aluminum evaporator, a zinc-based plated steel sheet is placed between the copper pipe and the evaporator to prevent melting of the aluminum by heating using a gas burner. Thus, the flame of the burner is prevented from touching the aluminum directly. When the above-described surface-treated steel sheet according to the prior art is applied to such a use, it is a film mainly composed of an organic resin, so that it is discolored to yellow or brown by thermal decomposition, resulting in poor appearance. For this reason, it is almost impossible to apply the surface-treated steel sheet of the prior art.

  In order to solve such a problem, a chromate-free technique excellent in heat discoloration has been proposed. For example, Patent Documents 6 and 7 propose an inorganic rich film mainly composed of Mg-phosphate, colloidal silica, and a phosphonic acid compound. Patent Document 8 proposes a two-layer coating in which an inorganic rich coating mainly composed of primary phosphate and colloidal silica is disposed as a lower layer, and a silicate coating and / or a silicon resin is disposed as an upper layer. Patent Document 9 discloses that at least one titanium compound selected from hydrolyzable titanium compounds, low-condensates of hydrolyzable titanium compounds, titanium hydroxide, and low-condensates of titanium hydroxide is hydrogen peroxide. Disclosed is a surface treatment composition containing a titanium-containing aqueous liquid obtained by mixing with water, an organic phosphoric acid, a water-soluble or water-dispersible organic resin, a vanadic acid compound, a zirconium fluoride compound, and a zirconium carbonate compound. .

JP 2000-79370 A JP 2001-348672 A JP 2004-91826 A Japanese Patent Laid-Open No. 2006-9121

  However, the inorganic rich coatings of Patent Documents 6 and 7 have extremely low corrosion resistance levels and are difficult to apply as a chromate coating substitute. On the other hand, the two-layer coating of Patent Document 8 has a corrosion resistance level applicable as a chromate coating substitute, but has a problem in terms of cost because it uses expensive silicate or silicon resin. In addition, the coatings produced by these technologies are subject to a phenomenon of black discoloration (black discoloration) in a humid environment, making it difficult to apply to heat exchangers that are subject to dew condensation, and the storage environment during product transportation. Are also impractical and impractical. Further, the surface treatment composition of Patent Document 9 improves the adhesion resistance when the fluoride contained therein improves the water-resistant adhesion and the corrosion resistance after alkaline degreasing, but has a relatively thick organic resin layer on the upper layer. I will invite you.

In addition, in organic resin-coated steel sheets such as coated steel sheets and laminated steel sheets, the adhesion of the organic resin layer is an important performance, but the conventional phosphating treatment that is performed as a base treatment has a crystalline film. Crystals are destroyed by strict processing, and the adhesion of the organic resin layer tends to be lowered. In particular, in the case of a coated steel sheet or a laminated steel sheet in which the thickness of the organic resin layer is 100 μm or more, the phosphate film is destroyed when the steel sheet is processed, and the organic resin layer is easily peeled off starting from this portion.
For such problems, for example, in Patent Documents 3 to 5 cited above, the plating metal on the substrate reacts with the treatment liquid to form a very thin film of poorly soluble phosphate, thereby providing corrosion resistance and paint adhesion. However, even when such a surface-treated steel sheet is used for an organic resin-coated steel sheet, the adhesion and corrosion resistance when processed are likely to deteriorate. In particular, in the case of an organic resin-coated steel sheet having an organic resin layer with a thickness of 100 μm or more, since the film strength is high, a strong shearing force acts on the interface between the organic resin layer and its base during deformation, and the organic resin layer Peeling easily occurs.

Therefore, the object of the present invention is to solve such a problem of the prior art, and to obtain excellent corrosion resistance, heat discoloration resistance and blackening resistance without containing hexavalent chromium, and is formed in the upper layer of the surface treatment film. It is to provide a surface-treated composition and a surface-treated steel sheet that can provide excellent adhesion with an organic resin layer, in particular, excellent adhesion when a thick organic resin layer having a thickness of 100 μm or more is deformed. .
Another object of the present invention is to provide an organic resin-coated steel sheet using such a surface-treated steel sheet.

  The inventors of the present invention have studied a film composition that can solve the above-described problems, and as a result, on the surface of a metal material (preferably a zinc-based plated steel sheet or an aluminum-based plated steel sheet), a specific titanium-containing aqueous liquid. Surface treatment with a surface treatment composition in which a zirconium carbonate compound, an organic phosphate compound, a metal phosphate, and silicon oxide are added in a predetermined ratio and, if necessary, a vanadic acid compound and an aqueous organic resin are added in appropriate amounts. By forming a film, excellent corrosion resistance, heat discoloration resistance and blackening resistance are obtained, and excellent adhesion to an organic resin layer formed as an upper layer, particularly a thick organic resin layer having a thickness of 100 μm or more. It was found that sex can be obtained.

Since this invention was made | formed based on such knowledge, it makes the following a summary.
[1] At least one titanium compound selected from hydrolyzable titanium compounds, hydrolyzable titanium compound low-condensates, titanium hydroxide, and titanium hydroxide low-condensates is mixed with hydrogen peroxide. 10 to 300 parts by mass of the zirconium carbonate compound (B) and 50 to 200 parts by mass of the organic phosphate compound (C) with respect to 100 parts by mass of the solid content of the resulting titanium-containing aqueous liquid (A), Containing 5 to 20 mass% of metal phosphate (D) in the total solid content of the surface treatment composition and 10 to 50 mass% of silicon oxide (E) in the total solid content of the surface treatment composition And a hexavalent chromium (however, excluding hexavalent chromium as an unavoidable impurity) is not contained , a surface treatment composition for a zinc-based plated steel sheet or an aluminum-based plated steel sheet .

[2] The surface treatment composition according to [1], further comprising 1 to 400 parts by mass of the vanadic acid compound (F) with respect to 100 parts by mass of the solid content of the titanium-containing aqueous liquid (A). A surface treatment composition for zinc-based plated steel sheet or aluminum-based plated steel sheet .
[3] In the surface treatment composition according to the above [1] or [2], the water-soluble organic resin and / or the water-dispersible organic resin (G) is further added in a proportion of 1 in the total solid content of the surface treatment composition. A surface treatment composition for a zinc-based plated steel sheet or an aluminum-based plated steel sheet , characterized by containing 10 to 10 mass%.
[4] In the surface treatment composition according to any one of [1] to [3] above, the solid content mass ratio (D) / (E) of the metal phosphate (D) to the silicon oxide (E) is 50 / A surface treatment composition for a zinc-based plated steel sheet or an aluminum-based plated steel sheet, wherein the composition is 50 to 10/90.

[5] In the surface treatment composition according to any one of the above [1] to [4], the silicon oxide (E) is a vapor-phase silica produced by a dry method, or a zinc-based plated steel sheet or aluminum Surface treatment composition for a plated steel sheet .
[6] The surface treatment composition for a zinc-based plated steel sheet or an aluminum-based plated steel sheet, wherein the bulk specific gravity of the vapor phase silica is 40 g / L or less in the surface treatment composition according to the above [5].
[7] A coating amount formed by applying the surface treatment composition of any one of [1] to [6] above to the surface of a zinc-based plated steel sheet or an aluminum-based plated steel sheet and drying it is 0.03. A surface-treated steel sheet having a surface-treated film of ˜2.0 g / m ² .
[8] An organic resin-coated steel sheet having an organic resin layer on the surface-treated film of the surface-treated steel sheet of [7].

Since the surface treatment film formed by the surface treatment composition of the present invention has a high level of barrier properties by being composed of a specific inorganic component, it has excellent corrosion resistance and blackening resistance comparable to a chromate film, In addition, it has excellent heat-resistant discoloration that is unlikely to cause coloration or discoloration due to heating, and furthermore, an organic resin layer formed as an upper layer, particularly an excellent organic resin layer having a thickness of 100 μm or more when deforming a steel sheet Have good adhesion.
In addition, the surface-treated steel sheet and the organic resin-coated steel sheet of the present invention are excellent in corrosion resistance, blackening resistance, and heat discoloration, and adherence of the organic resin layer, particularly adhesion of a thick organic resin layer having a thickness of 100 μm or more. Excellent in properties.

The surface treatment composition of the present invention contains a titanium-containing aqueous liquid (A), a zirconium carbonate compound (B), an organic phosphate compound (C), a metal phosphate (D), and silicon oxide (E). is there. This surface treatment composition does not contain hexavalent chromium (except for hexavalent chromium as an inevitable impurity).
The titanium-containing aqueous liquid (A) contains at least one titanium compound selected from hydrolyzable titanium compounds, hydrolyzable titanium compound low condensates, titanium hydroxide and titanium hydroxide low condensates. It is an aqueous liquid containing titanium obtained by mixing with hydrogen oxide water.

The hydrolyzable titanium compound is a titanium compound having a hydrolyzable group directly bonded to titanium, and generates titanium hydroxide by reacting with water such as water or water vapor. The hydrolyzable titanium compound may be one in which all of the groups bonded to titanium are hydrolyzable groups, or a part of the groups bonded to titanium may be hydrolyzable groups.
The hydrolyzable group is not particularly limited as long as it generates titanium hydroxide by reacting with moisture as described above. For example, a lower alkoxyl group or a group that forms a salt with titanium (for example, Halogen atoms such as chlorine, hydrogen atoms, sulfate ions, etc.).

The hydrolyzable titanium compound containing a lower alkoxyl group as the hydrolyzable group is particularly represented by the general formula Ti (OR) ₄ (wherein R represents the same or different alkyl groups having 1 to 5 carbon atoms). Tetraalkoxy titanium is preferred. Examples of the alkyl group having 1 to 5 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, an iso-butyl group, a sec-butyl group, and a tert-butyl group. Can be mentioned.
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.

Moreover, the low condensate of a hydrolysable titanium compound is a low condensate of the above-mentioned hydrolysable titanium compounds. The low condensate may be one in which all of the groups bonded to titanium are hydrolyzable groups, or a part of the groups bonded to titanium may be hydrolyzable.
For hydrolyzable titanium compounds whose hydrolyzable group forms a salt with titanium (for example, titanium chloride, titanium sulfate, etc.), an aqueous solution of the hydrolyzable titanium compound and an alkaline solution such as ammonia or caustic soda are used. Orthotitanic acid (titanium hydroxide gel) obtained by the reaction can also be used as a low condensate.

As the low condensate of the hydrolyzable titanium compound and the low condensate of titanium hydroxide, a compound having a condensation degree of 2 to 30 can be used, and a compound having a condensation degree of 2 to 10 is particularly preferable. If the degree of condensation is 30 or less, a stable titanium-containing aqueous liquid can be obtained by mixing with hydrogen peroxide.
The hydrolyzable titanium compounds, low condensates of hydrolysable titanium compounds, titanium hydroxide, and low condensates of titanium hydroxide can be used alone or in combination of two or more thereof. Tetraalkoxy titanium which is a hydrolyzable titanium compound represented by the formula is particularly preferable. The reason for this is that tetraalkoxytitanium does not affect the film performance such as corrosion resistance because the alcohol produced when hydrolyzed volatilizes in the process of drying the surface treatment composition, and has particularly excellent film performance. It is because it is obtained.

As the titanium-containing aqueous liquid (A), any conventionally known liquid can be used without particular limitation as long as it is an aqueous liquid containing titanium obtained by mixing the above-described titanium compound and hydrogen peroxide solution. Specifically, the following can be mentioned.
(I) A titanyl ion hydrogen peroxide complex or an aqueous solution of titanic acid (peroxotitanium hydrate) obtained by adding hydrogen peroxide to a hydrous titanium oxide gel or sol (JP-A 63-35419, JP-A 1-2224220 gazette).

(Ii) A liquid for forming a titania film obtained by synthesizing a titanium hydroxide gel produced from an aqueous solution of titanium chloride or titanium sulfate and a basic solution with a hydrogen peroxide solution (Japanese Patent Laid-Open No. 9-71418, (See Kaihei 10-67516).
When obtaining this titania film-forming liquid, titanium hydroxide gel called orthotitanic acid is precipitated by reacting an aqueous solution of titanium chloride or titanium sulfate having a salt-forming group with titanium and an alkaline solution such as ammonia or caustic soda. Let Next, the titanium hydroxide gel is separated by decantation with water, washed thoroughly with water, further added with hydrogen peroxide water, and excess hydrogen peroxide is decomposed and removed, whereby a yellow transparent viscous liquid can be obtained.

The precipitated orthotitanic acid is in a gel state polymerized by polymerization of OH or hydrogen bonds, and cannot be used as an aqueous liquid containing titanium as it is. When hydrogen peroxide solution is added to this gel, a part of OH is in a peroxidized state, dissolved as a peroxotitanate ion or in a kind of sol state in which the polymer chain is divided into low molecules, and excess hydrogen peroxide Is decomposed into water and oxygen, and can be used as an aqueous liquid containing titanium for forming an inorganic film.
Since this sol contains only oxygen and hydrogen atoms in addition to titanium atoms, when it is changed to titanium oxide by drying or firing, only water and oxygen are generated, so carbon components necessary for thermal decomposition such as sol-gel method and sulfate Further, it is not necessary to remove the halogen component, and a titanium oxide film having a relatively high density can be formed even at a low temperature.

(Iii) Hydrogen peroxide is added to an aqueous solution of an inorganic titanium compound such as titanium chloride or titanium sulfate to form peroxotitanium hydrate, and then the solution obtained by adding a basic substance is allowed to stand or be heated. A titanium oxide forming solution obtained by forming a precipitate of a titanium hydrate polymer, and then removing hydrogen and other dissolved components derived from at least a titanium-containing raw material solution (Japanese Patent Application Laid-Open 2000-247638, JP-A-2000-247639).

The titanium-containing aqueous liquid (A) using a hydrolyzable titanium compound and / or a low condensate thereof as a titanium compound (hereinafter referred to as “hydrolyzable titanium compound a” for convenience of explanation) contains hydrolyzable titanium compound a. It can be obtained by reacting with hydrogen oxide water at a reaction temperature of 1 to 70 ° C. for about 10 minutes to 20 hours.
In the titanium-containing aqueous liquid (A) using the hydrolyzable titanium compound a, the hydrolyzable titanium compound a is hydrolyzed with water by reacting the hydrolyzable titanium compound a with hydrogen peroxide. A product obtained by producing a hydroxyl group-containing titanium compound and then coordinating hydrogen peroxide to this hydroxyl group-containing titanium compound, and this hydrolysis reaction and coordination by hydrogen peroxide occur simultaneously. It produces a chelate solution that is extremely stable at room temperature and can withstand long-term storage. The titanium hydroxide gel used in the conventional manufacturing method is partially three-dimensionalized by Ti—O—Ti bonds, and the titanium-containing aqueous liquid (A) obtained by reacting this gel with hydrogen peroxide is composition and stable. Sex is essentially different.

  Further, when the titanium-containing aqueous liquid (A) using the hydrolyzable titanium compound a is heated or autoclaved at 80 ° C. or higher, a titanium oxide dispersion containing ultrafine particles of crystallized titanium oxide is obtained. If the heat treatment or autoclave treatment is performed at 80 ° C. or higher, the crystallization of titanium oxide can be sufficiently advanced. The average particle diameter of the titanium oxide ultrafine particles of the titanium oxide dispersion produced in this manner is 10 nm or less, preferably about 1 to 6 nm. When the average particle diameter of the titanium oxide ultrafine particles is 10 nm or less, the film-forming property is excellent (when the film is dried after coating to form a film, cracking does not occur when the film thickness is 1 μm or more). Moreover, if the average particle diameter of the titanium oxide ultrafine particles is 1 nm or more, it is preferable because the surface treatment composition can be maintained in a state where the viscosity does not increase. The appearance of this titanium oxide dispersion is translucent. Such a titanium oxide dispersion can also be used as the titanium-containing aqueous liquid (A).

The surface treatment composition (H) containing the titanium-containing aqueous liquid (A) using the hydrolyzable titanium compound a is applied to the surface of the plated steel plate and dried (for example, heat-dried at a low temperature), thereby adhering to itself. A dense titanium oxide-containing film (surface treatment film) having excellent properties can be formed.
The heating temperature of the steel sheet after the application of the surface treatment composition (H) is, for example, preferably 200 ° C. or lower, particularly preferably 150 ° C. or lower. Amorphous) titanium oxide-containing film can be formed.
In addition, when the titanium oxide dispersion obtained through the heat treatment or autoclave treatment as described above at 80 ° C. or more is used as the titanium-containing aqueous liquid (A), the crystal can be obtained by simply applying the surface treatment composition (H). It is useful as a coating material for materials that cannot be heat-treated.

Further, as the titanium-containing aqueous liquid (A), a titanium-containing aqueous liquid (A1) obtained by reacting the hydrolyzable titanium compound a with hydrogen peroxide in the presence of a titanium oxide sol can also be used. .
The titanium oxide sol is a sol in which amorphous titania fine particles and / or anatase type titania fine particles are dispersed in water (for example, an aqueous organic solvent such as an alcohol or alcohol ether may be added if necessary). As this titanium oxide sol, conventionally known ones can be used. For example, (i) a titanium oxide aggregate obtained by hydrolyzing a titanium-containing solution such as titanium sulfate or titanyl sulfate, (ii) titanium alkoxide, etc. Titanium oxide aggregates obtained by hydrolyzing organic titanium compounds of the above, (iii) Titanium oxide aggregates obtained by hydrolyzing or neutralizing titanium halide solutions such as titanium tetrachloride, etc. An amorphous titania sol dispersed in water, or a sol in which the titanium oxide aggregates are calcined to form anatase-type titanium fine particles and this is dispersed in water can be used.

In the firing of the amorphous titania, the amorphous titania can be converted into anatase titania by firing at a temperature at least higher than the crystallization temperature of anatase, for example, 400 ° C. to 500 ° C. or more. Examples of the aqueous sol of titanium oxide include, for example, TKS-201 (trade name, manufactured by Teika, anatase crystal form, average particle diameter 6 nm), TA-15 (trade name, manufactured by Nissan Chemical Co., anatase crystal form). STS-11 (trade name, manufactured by Ishihara Sangyo Co., Ltd., anatase type crystal form) and the like.
In the titanium-containing aqueous liquid (A1), the mass ratio x / y between the titanium oxide sol x and the titanium hydrogen peroxide reactant y (reaction product of the hydrolyzable titanium compound a and hydrogen peroxide solution) is 1 / A range of 99 to 99/1, preferably about 10/90 to 90/10 is suitable. If the mass ratio x / y is 1/99 or more, the effect of adding the titanium oxide sol is sufficiently obtained in terms of stability, photoreactivity, and the like, and if it is 99/1 or less, excellent film formation is achieved. It is preferable because of its property.

The titanium-containing aqueous liquid (A1) can be obtained by reacting the hydrolyzable titanium compound a with hydrogen peroxide at a reaction temperature of 1 to 70 ° C. for about 10 minutes to 20 hours in the presence of a titanium oxide sol.
The production form and characteristics of the titanium-containing aqueous liquid (A1) are the same as those of the titanium-containing aqueous liquid (A) using the hydrolyzable titanium compound a described above, but in particular, by using a titanium oxide sol. , It is possible to suppress a partial condensation reaction during the synthesis to increase the viscosity. The reason is considered to be that the condensation reaction product is adsorbed on the surface of the titanium oxide sol, and polymerization in a solution state is suppressed.
Further, when the titanium-containing aqueous liquid (A1) is heated or autoclaved at 80 ° C. or higher, a titanium oxide dispersion containing ultrafine particles of crystallized titanium oxide is obtained. The titanium-containing aqueous liquid (A) using the hydrolyzable titanium compound a described above also describes the temperature conditions for obtaining this titanium oxide dispersion, the particle diameter of the crystallized titanium oxide ultrafine particles, the appearance of the dispersion, etc. It is the same. Such a titanium oxide dispersion can also be used as the titanium-containing aqueous liquid (A1).

Similar to the titanium-containing aqueous liquid (A) using the hydrolyzable titanium compound a described above, the surface treatment composition (H) containing the titanium-containing aqueous liquid (A1) is applied to the surface of the plated steel sheet and dried (for example, By heating and drying at a low temperature, it is possible to form a dense titanium oxide-containing film (surface-treated film) having excellent adhesion by itself.
The heating temperature of the steel sheet after the application of the surface treatment composition (H) is, for example, 200 ° C. or less, particularly preferably 150 ° C. or less. By heating and drying at such a temperature, anatase-type oxidation slightly containing hydroxyl groups A titanium-containing film can be formed.
As described above, of the titanium-containing aqueous liquid (A), the titanium-containing aqueous liquid (A) and the titanium-containing aqueous liquid (A1) using the hydrolyzable titanium compound a are excellent in storage stability, corrosion resistance, and the like. It is particularly preferable to use these in the present invention.

The compounding ratio of hydrogen peroxide water to at least one titanium compound selected from hydrolyzable titanium compounds, hydrolyzable titanium compound low condensates, titanium hydroxide, titanium hydroxide low condensates is titanium compounds It is preferably 0.1 to 100 parts by mass, preferably 1 to 20 parts by mass in terms of hydrogen peroxide with respect to 10 parts by mass. If the blending ratio of hydrogen peroxide water is 0.1 parts by mass or more in terms of hydrogen peroxide, chelate formation is sufficient so that no cloudy precipitation occurs. On the other hand, if it is 100 parts by mass or less, unreacted This is preferable because no hydrogen peroxide remains, and no active oxygen is released during storage.
The hydrogen peroxide concentration of the hydrogen peroxide solution is not particularly limited, but it is preferably about 3 to 30% by mass from the viewpoint of ease of handling and the solid content of the product liquid related to coating workability.

Other sols and pigments can be added and dispersed in the titanium-containing aqueous liquid (A) as necessary. Examples of the additive include commercially available titanium oxide sol, titanium oxide powder, mica, talc, barita, clay, and the like, and one or more of these can be added.
The content of the titanium-containing aqueous liquid (A) in the surface treatment composition is preferably 1 to 100 g / L, preferably 5 to 50 g / L in terms of solid content from the viewpoint of the stability of the treatment liquid. .

  The surface treatment composition of the present invention further improves the corrosion resistance by adding the zirconium carbonate compound (B) to the titanium-containing aqueous liquid (A), and an organic resin layer (an organic resin layer formed by lamination or coating). The corrosion resistance after coating with the organic resin layer is significantly improved. In addition, the organophosphate compound (C) increases the reactivity with the steel sheet to improve the corrosion resistance, and also improves the storage stability of the surface treatment composition. Furthermore, by adding metal phosphate (D) and silicon oxide (E), an organic resin layer formed as an upper layer, particularly a thick organic resin layer having a thickness of 100 μm or more (for example, formed by lamination). The adhesion of the organic resin layer) during deformation of the steel sheet is improved.

  As the zirconium carbonate compound (B), ammonium zirconium carbonate, zirconium oxycarbonate, and the like are suitable. By using one or more of these, corrosion resistance can be improved. The compounding quantity of a zirconium carbonate compound (B) shall be 10-300 mass parts with respect to 100 mass parts of solid content of a titanium containing aqueous liquid (A), Preferably it is 50-100 mass parts. When the blending amount of the zirconium carbonate compound (B) is less than 10 parts by mass with respect to 100 parts by mass of the solid content of the titanium-containing aqueous liquid (A), the effect of improving the corrosion resistance is small. Tend to deteriorate.

  Examples of the organic phosphoric acid compound (C) include hydroxyl groups such as 1-hydroxymethane-1,1-diphosphonic acid, 1-hydroxyethane-1,1-diphosphonic acid, and 1-hydroxypropane-1,1-diphosphonic acid. 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 are preferred. 1 type (s) or 2 or more types can be used.

The organic phosphoric acid compound (C) has the effect of improving the corrosion resistance and the storage stability of the titanium-containing aqueous liquid (A). Among them, 1-hydroxyethane-1,1-diphosphonic acid is particularly effective. Therefore, it is particularly preferable to use this.
The compounding amount of the organic phosphoric acid compound (C) is 50 to 200 parts by mass, particularly 70 to 150 parts by mass with respect to 100 parts by mass of the solid content of the titanium-containing aqueous liquid (A). It is preferable from the point. When the compounding amount of the organic phosphoric acid compound (C) is less than 50 parts by mass with respect to 100 parts by mass of the solid content of the titanium-containing aqueous liquid (A), the storage stability of the surface treatment composition is inferior and the corrosion resistance is reduced. It is done. On the other hand, when it exceeds 200 mass parts, water-resistant adhesiveness is inferior.

Metal phosphate (D) and silicon oxide (E) are blended in order to improve adhesion to an organic resin layer formed as an upper layer by laminating or the like, particularly a thick organic resin layer having a thickness of 100 μm or more. It is something to be made. Examples of the silicon oxide (E) include amorphous silica such as liquid phase silica and gas phase silica, and one or more of these can be used. Specifically, as colloidal silica, Snow Chemicals (registered trademark) O, N, 20, 30, 40, C, S manufactured by Nissan Chemical Industries, Ltd., and as vapor phase silica, manufactured by Nippon Aerosil Co., Ltd. AEROSIL (registered trademark) 130, 200, 200V, 200CF, 300, 300CF or the like can be used.
Among these, vapor-phase silica produced by a dry method is very preferable from the viewpoint of adhesion to the organic resin layer, and good performance can be obtained.

  Moreover, although there is no special restriction | limiting in the kind of metal phosphate (D), Aluminum salt, magnesium salt, and manganese salt are effective especially. In particular, in the case of an aluminum salt, there is an advantage that the solubility of the phosphate is lowered and the effect in a humid environment is sustained. 1 type (s) or 2 or more types can be used for said metal phosphate. Further, as the metal phosphate (D), it is preferable to apply a commercially available aqueous solution in which the phosphoric acid / metal cation component ratio is rich in phosphoric acid in advance so that it can exist as an aqueous solution.

In order to add (compound) the metal phosphate (D) and the silicon oxide (E) in the surface treatment composition, the metal phosphate (D) and the silicon oxide (E) are mixed in advance, It is preferable to add in the form of this mixture. More excellent adhesion and corrosion resistance can be obtained when added in a premixed state than when added separately. Although this reason is not necessarily clear, it is thought that it is because the cohesive force of the film obtained by the surface treatment composition is increased by the effect of the phosphoric acid component. Moreover, the storage stability of the surface treatment composition is improved by mixing by this method.
When silica (gas phase silica) produced by a dry method is used as silicon oxide (E), the metal phosphate aqueous solution is obtained by adding the gas phase silica to the metal phosphate aqueous solution and stirring vigorously. A silicon oxide dispersion liquid in which vapor phase silica is dispersed may be prepared in advance and mixed with other components. Alternatively, the surface treatment composition may be prepared by vigorously stirring the vapor phase silica and the metal phosphate aqueous solution together with other compounding components and water.

  Further, when vapor phase silica is dispersed in the surface treatment composition with a sand mill or the like, aggregation occurs in about one week to several weeks, and a precipitate is generated. Although the detailed mechanism is not clear, it has been found that it is effective to use gas phase silica having a low bulk specific gravity in order to prevent such aggregation and improve storage stability (chemical solution stability). It was. Specifically, it is preferable to use gas phase silica having a bulk specific gravity of 40 g / L or less. The bulk specific gravity of the vapor phase silica can be adjusted by controlling the deaeration conditions after the production by the dry method, whereby a vapor phase silica having a small bulk specific gravity can be obtained.

  The adhesion of the organic resin layer is improved by blending the metal phosphate (D) and the silicon oxide (E). The surface polarity of the surface treatment film is changed by blending the silicon oxide and the metal phosphate. It is thought that this is because it acts on the adhesiveness advantageously. Since silicon oxide increases the polarity, it has the effect of increasing the adhesion with the resin layer and the adhesive layer when the organic resin layer is directly applied to the upper layer or when the organic resin film is brought into close contact with the adhesive. On the other hand, if the polarity is too high, it becomes easy to take in moisture in a humid environment, which is disadvantageous for swelling. On the other hand, by blending nonpolar phosphoric acid (metal phosphate), it is possible to realize an appropriate surface polarity that can achieve both adhesion and stability when wet. Furthermore, secondary aggregation of silicon oxide forms surface irregularities on the order of submicrons, and the formation of such surface irregularities increases the effective area at the adhesion interface, thus effectively acting on adhesion. It is considered a thing. Although the influence on the texture due to the incorporation of the metal phosphate is not sufficiently clear, it is considered that the texture is affected by acting on the secondary aggregation of silicon oxide.

The compounding amount of the metal phosphate (D) is 5 to 20 mass% as a ratio in the total solid content of the surface treatment composition, and the compounding amount of the silicon oxide (E) is in the total solid content of the surface treatment composition. The ratio is 10 to 50 mass%.
If the blending amount of the metal phosphate (D) is less than 5 mass% in the total solid content of the surface treatment composition, the effect is not exhibited, the adhesion to the steel sheet becomes insufficient, and the organic Corrosion resistance after coating of the resin layer also deteriorates. On the other hand, when it exceeds 20 mass% and it adds excessively, it becomes a factor which worsens performance, such as blackening at the time of storage until it coat | covers an organic resin layer.

  When the blending amount of silicon oxide (E) is less than 10 mass% in the total solid content of the surface treatment composition, the formation of irregularities on the order of submicron becomes insufficient and sufficient adhesion with the upper organic resin layer is achieved. Sex cannot be obtained. On the other hand, if it exceeds 50 mass%, good adhesion can be obtained, but the barrier property of the surface treatment film is impaired, the permeation of corrosive factors in the corrosive environment cannot be suppressed, and the plating layer is easily corroded. Moreover, from the above viewpoint, the compounding amount of silicon oxide (E) is more preferably 20 to 40 mass% in terms of the total solid content of the surface treatment composition.

The solid content mass ratio (D) / (E) of the metal phosphate (D) and the silicon oxide (E) is 50/50 to 10/90, more preferably 40/60 to 10/90, still more preferably. It is good to set it as 30 / 70-20 / 80. By adding the metal phosphate (D) and the silicon oxide (E) in combination, when a thick organic resin layer is coated, corrosion in a corrosive environment with high humidity as in a salt spray test is unlikely to occur.
Under such conditions, blistering from the resin layer missing part such as edges and scratches usually occurs, but such blistering is suppressed by the combined addition of metal phosphate (D) and silicon oxide (E). Is done. When the ratio of silicon oxide (E) is too small, the adhesiveness is lowered, so that the swelling suppressing effect cannot be sufficiently obtained. On the other hand, if the ratio of the metal phosphate (D) is too small, the effect of inhibiting corrosion of zinc cannot be obtained, and the effect of inhibiting swelling is also reduced. For the above reasons, the solid content mass ratio (D) / (E) between the metal phosphate (D) and the silicon oxide (E) is preferably in the range of 50/50 to 10/90.

The surface treatment composition of the present invention essentially comprises the titanium-containing aqueous liquid (A) and the components (B) to (E) as described above. If necessary, a vanadate compound (F ), Water-soluble organic resin and / or water-dispersible organic resin (G).
Examples of the vanadic acid compound (F) include lithium metavanadate, potassium metavanadate, sodium metavanadate, ammonium metavanadate, and anhydrous vanadate, and one or more of these can be used. Of these, ammonium metavanadate is preferable from the viewpoint of water adhesion resistance.

  The amount of the vanadic acid compound (F) is 1 to 400 parts by mass, particularly 10 to 400 parts by mass with respect to 100 parts by mass of the solid content of the titanium-containing aqueous liquid (A). It is preferable from the viewpoint of later corrosion resistance. If the compounding amount of the vanadic acid compound (F) is 400 parts by mass or less with respect to 100 parts by mass of the solid content of the titanium-containing aqueous liquid (A), V does not exist excessively, so after alkali degreasing The corrosion resistance of can be fully expressed.

  The water-soluble organic resin and / or water-dispersible organic resin (G) is an organic resin that can be dissolved or dispersed in water, and a conventionally known method for water-solubilizing or dispersing an organic resin in water. The method can be applied. Specifically, the organic resin contains a functional group (for example, a hydroxyl group, a polyoxyalkylene group, a carboxyl group, an amino (imino) group, a sulfide group, a phosphine group, etc.) that can be water-soluble or water-dispersed independently. , And if necessary, part or all of these functional groups are amine compounds such as ethanolamine and triethylamine if acidic resin (carboxyl group-containing resin, etc.); ammonia water; lithium hydroxide, sodium hydroxide, water Neutralized with alkali metal hydroxides such as potassium oxide, and fatty acids such as acetic acid and lactic acid for basic resins (amino group-containing resins); those neutralized with mineral acids such as phosphoric acid Can be used.

Examples of water-soluble or water-dispersible organic resins include epoxy resins, phenolic resins, acrylic resins, urethane resins, olefin-carboxylic acid resins, nylon resins, resins having a polyoxyalkylene chain, and polyvinyl alcohol. , Polyglycerin, carboxymethylcellulose, hydroxymethylcellulose, hydroxyethylcellulose and the like. The said organic resin can use 1 type (s) or 2 or more types.
Among these, the use of at least one organic resin selected from water-soluble or water-dispersible acrylic resins, urethane resins, and epoxy resins from the viewpoint of storage stability of the surface treatment composition. In particular, it is preferable to use a water-soluble or water-dispersible acrylic resin or urethane resin as a main component from the viewpoint of the balance between the storage stability of the surface treatment composition and the coating film performance. Furthermore, in order to ensure excellent adhesion, it is preferable to use a urethane-based resin having a Tg (glass transition point) of less than 50 ° C.

A water-soluble or water-dispersible acrylic resin is prepared by a conventionally known method, for example, an emulsion polymerization method, a suspension polymerization method, a polymer having a hydrophilic group by solution polymerization, and neutralized or made aqueous if necessary. Or the like.
The polymer having a hydrophilic group includes, for example, an unsaturated monomer having a hydrophilic group such as a carboxyl group, an amino group, a hydroxyl group, and a polyoxyalkylene group, and, if necessary, other unsaturated monomers. It can be obtained by polymerizing the monomer.
The water-soluble or water-dispersible acrylic resin is preferably one obtained by copolymerizing styrene from the viewpoint of corrosion resistance, and the amount of styrene in the total unsaturated monomer is 10 to 60% by mass, particularly 15 to 50% by mass. It is preferable that Moreover, it is preferable from points, such as toughness of the film obtained, that Tg (glass transition point) of the acrylic resin obtained by copolymerization is 30-80 degreeC, especially 40-70 degreeC.

Examples of the carboxyl group-containing unsaturated monomer include acrylic acid, methacrylic acid, maleic acid, maleic anhydride, crotonic acid, and itaconic acid.
Examples of the nitrogen-containing unsaturated monomer such as the amino group-containing unsaturated monomer include N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, Nt- Nitrogen-containing alkyl (meth) acrylates such as butylaminoethyl (meth) acrylate; acrylamide, methacrylamide, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N-methylol (meth) acrylamide, N-methoxymethyl Polymerization of (meth) acrylamide, N-butoxymethyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, N, N-dimethylaminoethyl (meth) acrylamide, etc. Amides; 2-vinylpyridine, - vinyl-2-pyrrolidone, aromatic nitrogen-containing monomers such as 4-vinylpyridine; and allylamine and the like.

  Examples of the hydroxyl group-containing unsaturated monomer include 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, 2,3-dihydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, polyethylene glycol mono Monoesterified product of polyhydric alcohol such as (meth) acrylate, polypropylene glycol mono (meth) acrylate and acrylic acid or methacrylic acid; ε-caprolactone is opened to monoesterified product of polyhydric alcohol and acrylic acid or methacrylic acid. Examples include a ring-polymerized compound.

Other unsaturated monomers include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, 1 carbon number such as tert-butyl (meth) acrylate, 2-ethylhexyl acrylate, n-octyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, octadecyl (meth) acrylate, isostearyl (meth) acrylate -24 alkyl (meth) acrylates; vinyl acetate and the like.
The unsaturated monomer mentioned above can use 1 type (s) or 2 or more types. In the description of the present application, “(meth) acrylate” means “acrylate or methacrylate”.

  Examples of the urethane-based resin include a chain extender which is a low molecular weight compound having two or more active hydrogens such as a diol and a diamine as needed, and a polyurethane composed of a polyol and a diisocyanate such as polyester polyol and polyether polyol. Those which are chain-extended in the presence and stably dispersed or dissolved in water can be suitably used, and conventionally known ones can be widely used (for example, Japanese Patent Publication No. 42-24192, Japanese Patent Publication No. 42-24194, (See JP-B-42-5118, JP-B-49-986, JP-B-49-33104, JP-B-50-15027, JP-B-53-29175).

As a method for stably dispersing or dissolving the polyurethane resin in water, for example, the following method can be used.
(1) A method of imparting hydrophilicity by introducing an ionic group such as a hydroxyl group, an amino group or a carboxyl group into the side chain or terminal of a polyurethane polymer, and dispersing or dissolving in water by self-emulsification.
(2) A polyurethane polymer whose reaction has been completed or a polyurethane polymer whose terminal isocyanate group has been blocked with a blocking agent such as oxime, alcohol, phenol, mercaptan, amine, sodium bisulfite, etc. How to disperse. Further, a method in which a urethane polymer having a terminal isocyanate group is mixed with water, an emulsifier and a chain extender, and dispersion and high molecular weight are simultaneously performed using mechanical shearing force.
(3) A method in which a water-soluble polyol such as polyethylene glycol is used as a polyol as a main polyurethane material, and is dispersed or dissolved in water as a water-soluble polyurethane.
In addition, what was obtained by the different method among the dispersion | distribution or melt | dissolution methods mentioned above can also mix and use a polyurethane-type resin.

Examples of the diisocyanate that can be used for the synthesis of the polyurethane resin include aromatic, alicyclic or aliphatic diisocyanates. Specifically, hexamethylene diisocyanate, tetramethylene diisocyanate, 3,3′-dimethoxy-4, 4'-biphenylene diisocyanate, p-xylylene diisocyanate, m-xylylene diisocyanate, 1,3- (diisocyanatomethyl) cyclohexanone, 1,4- (diisocyanatomethyl) cyclohexanone, 4,4'-diisocyanato Cyclohexanone, 4,4'-methylenebis (cyclohexyl isocyanate), isophorone diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, p-phenylene diisocyanate, diphenylmethane di Isocyanate, m- phenylene diisocyanate, 2,4-naphthalene diisocyanate, 3,3'-dimethyl-4,4'-biphenylene diisocyanate, 4,4'-biphenylene diisocyanate and the like. Among these, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate are particularly preferable.
Examples of commercially available polyurethane resins include Hydran (registered trademark) HW-330, HW-340, HW-350 (both trade names, manufactured by Dainippon Ink and Chemicals), Superflex (registered trademark) 100, 150, E-2500, F-3438D (all trade names, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and the like.

  As the epoxy resin, a cationic epoxy resin obtained by adding an amine to an epoxy resin; a modified epoxy resin such as an acrylic modification or a urethane modification can be preferably used. Examples of cationic epoxy resins include adducts of epoxy compounds with primary mono- or polyamines, secondary mono- or polyamines, and primary and secondary mixed polyamines (see, for example, US Pat. No. 3,984,299). An adduct of an epoxy compound and a secondary mono- or polyamine having a ketiminated primary amino group (see, for example, US Pat. No. 4,017,438); an epoxy compound having a ketiminated primary amino group Examples include etherification reaction products with hydroxyl compounds (see, for example, JP-A-59-43013).

  As the epoxy resin, those having a number average molecular weight of 400 to 4000, particularly 800 to 2000, and an epoxy equivalent of 190 to 2000, particularly 400 to 1000 are preferable. Such an epoxy resin can be obtained, for example, by a reaction between a polyphenol compound and epirulhydrin, and examples of the polyphenol compound include bis (4-hydroxyphenyl) -2,2-propane, 4,4. -Dihydroxybenzophenone, bis (4-hydroxyphenyl) -1,1-ethane, bis (4-hydroxyphenyl) -1,1-isobutane, bis (4-hydroxy-tert-butylphenyl) -2,2-propane, Bis (2-hydroxynaphthyl) methane, 1,5-dihydroxynaphthalene, bis (2,4-dihydroxyphenyl) methane, tetra (4-hydroxyphenyl) -1,1,2,2-ethane, 4,4-dihydroxy Diphenylsulfone, phenol novolak, cresol novolak, etc. That.

The blending amount of the water-soluble organic resin and / or the water-dispersible organic resin (G) is preferably 1 to 10 mass% as a ratio in the total solid content of the surface treatment composition. If the blending amount of the water-soluble organic resin and / or water-dispersible organic resin (G) is 1 mass% or more in terms of the total solid content of the surface treatment composition, a sufficient effect can be obtained, while 10 mass%. If it is below, heat discoloration will not be lowered.
If necessary, the surface treatment composition of the present invention may further include, for example, an etching agent such as a silane coupling agent, resin fine particles, and an inorganic phosphate compound, a heavy metal compound other than the components specified by the present invention, a thickener, A surfactant, a lubricity-imparting agent (polyethylene wax, fluorine-based wax, carnauba wax, etc.), a rust inhibitor, a color pigment, an extender pigment, a rust preventive pigment, and a dye can be contained. In particular, in order to improve the adhesion with the organic resin layer, it is preferable to contain a silane coupling agent.

Moreover, the surface treatment composition of this invention can be diluted with hydrophilic solvents, such as methanol, ethanol, isopropyl alcohol, an ethylene glycol type solvent, a propylene glycol type solvent, for example as needed, and can be used.
The surface treatment composition of the present invention preferably has a solid content of about 2 to 10 mass% from the viewpoints of storage stability and stability during coating.
The surface treatment composition of the present invention can be used as a surface treatment agent for various metal materials, but is particularly suitable as a surface treatment agent for zinc-based plated steel sheets and aluminum-based plated steel sheets described later.

The surface-treated steel sheet of the present invention has a surface-treated composition as described above, that is, a titanium-containing aqueous liquid (A), a zirconium carbonate compound (B), and an organic phosphate compound on the surface of a zinc-based plated steel sheet or an aluminum-based plated steel sheet. (C), metal phosphate (D) and silicon oxide (E) (preferably contained as main components), and if necessary, vanadate compound (F), water-soluble organic resin or / And a surface treatment film having a predetermined film adhesion amount formed by applying and drying a surface treatment composition containing at least one of the water-dispersible organic resin (G). This surface-treated film does not contain hexavalent chromium (except for hexavalent chromium as an inevitable impurity).
Further, the titanium-containing aqueous liquid (A) and the surface treatment composition may further contain other additive components as mentioned above, if necessary.

Examples of the galvanized steel sheet used as the base of the surface-treated steel sheet of the present invention include a galvanized steel sheet, a Zn—Ni alloy plated steel sheet, a Zn—Fe alloy plated steel sheet (electroplated steel sheet, galvannealed steel sheet), Zn -Cr alloy plated steel sheet, Zn-Mn alloy plated steel sheet, Zn-Co alloy plated steel sheet, Zn-Co-Cr alloy plated steel sheet, Zn-Cr-Ni alloy plated steel sheet, Zn-Cr-Fe alloy plated steel sheet, Zn-Al Alloy-plated steel sheets (for example, Zn-5 mass% Al alloy-plated steel sheets, Zn-55 mass% Al alloy-plated steel sheets), Zn-Mg alloy-plated steel sheets, Zn-Al-Mg alloy-plated steel sheets, and plating of these plated steel sheets metal oxides, dispersed zinc composite-plated steel sheet such as a polymer (e.g., Zn-SiO ₂ dispersion plating steel plate) used like in the coating Door can be. Moreover, the multilayer plating steel plate which plated two or more layers of the same kind or different kind among the above plating can also be used.

Moreover, as an aluminum system plated steel plate used as the base of the surface treatment steel plate of this invention, an aluminum plating steel plate, an Al-Si alloy plating steel plate, etc. can be used.
Moreover, as a plated steel plate, the steel plate surface may be previously plated with lightness such as Ni, and various plating as described above may be performed thereon.
As a plating method, any feasible method among an electrolytic method (electrolysis in an aqueous solution or electrolysis in a nonaqueous solvent), a melting method, and a gas phase method can be adopted.
In addition, when the surface treatment film is formed on the surface of the plating film, alkali degreasing, solvent degreasing, surface conditioning treatment (alkaline surface conditioning) is performed on the surface of the plating film as necessary in order to prevent film defects and unevenness from occurring. Treatment or acidic surface conditioning treatment) can be performed.

In addition, for the purpose of preventing blackening in the usage environment (a kind of oxidation phenomenon on the plating surface), an iron group metal ion (one or more kinds of Ni ion, Co ion, Fe ion) is previously applied to the plating surface as necessary. Surface adjustment treatment with an acidic or alkaline aqueous solution containing can also be performed.
When using an electrogalvanized steel sheet as the base steel sheet, iron group metal ions (one or more of Ni ions, Co ions, Fe ions) are added to the electroplating bath for the purpose of preventing blackening, and the plating film These metals can be contained in an amount of 1 mass ppm or more. In this case, there is no particular limitation on the upper limit of the iron group metal concentration in the plating film.
Adhesion amount of surface treated film formed by a surface treatment composition, 0.03~2.0g / ^{m 2,} preferably between 0.05 to 1.0 g / ^{m 2.} When the coating amount is less than 0.03 g / m ² , the corrosion resistance is inferior. On the other hand, when the coating amount exceeds 2.0 g / m ² , the coating is liable to break, and the corrosion resistance and adhesion deteriorate. Moreover, a more preferable adhesion amount is 0.1 to 0.5 g / m ² .

In order to produce the surface-treated steel sheet of the present invention, the surface treatment composition as described above, that is, the titanium-containing aqueous liquid (A), the zirconium carbonate compound (B), on the surface of the zinc-based plated steel sheet or the aluminum-based plated steel sheet, Contains an organic phosphate compound (C), metal phosphate (D) and silicon oxide (E) (preferably contained as a main component), and further, if necessary, vanadate compound (F), water-soluble After apply | coating the surface treatment composition (treatment liquid) containing 1 or more types of organic resin or / and water-dispersible organic resin (G), it dries without washing with water.
Further, the titanium-containing aqueous liquid (A) and the surface treatment composition may further contain other additive components as mentioned above, if necessary.

The means for applying the surface treatment composition (treatment liquid) is optional, for example, spray + roll squeezing, roll coater, etc. Also, the drying method after application is also, for example, a hot air method, induction heating method, electric furnace method, etc. Is optional.
The drying temperature (steel plate temperature) of the applied surface treatment composition (treatment liquid) is preferably about 60 to 200 ° C. When the drying temperature is 60 ° C. or higher, film formation is sufficient and a film having excellent corrosion resistance and the like is obtained. On the other hand, if the drying temperature is 200 ° C. or less, cracks are not generated in the film due to heat, so that a sufficient effect of improving corrosion resistance is obtained. Moreover, a more preferable drying temperature is 60-140 degreeC, Furthermore, 60-90 degreeC is more preferable.

The organic resin-coated steel sheet of the present invention is obtained by forming an organic resin layer on the surface-treated film of the surface-treated steel sheet as described above. The method for forming the organic resin layer is arbitrary, and for example, a method of applying and drying a coating composition, a method of laminating an organic resin film, and the like can be applied.
Moreover, since the surface treatment film of the present invention is particularly excellent in adhesion of a thick organic resin layer having a thickness of 100 μm or more, the organic resin-coated steel sheet of the present invention has an organic resin layer thickness of 100 μm or more. Is particularly useful.
The organic resin layer may contain various additives including non-chromium rust preventive additives, solid lubricants, color pigments and the like.

The titanium-containing aqueous liquid (A) and components (B) to (G) used in the surface treatment composition are shown below.
[Production of titanium-containing aqueous liquid (A)]
Production Example 1 (Titanium-containing aqueous liquid T1)
Ammonia water (1: 9 = ammonia: water mass ratio) was added dropwise to a solution in which 5 cc of a titanium tetrachloride 60 mass% solution was made 500 cc with distilled water to precipitate a low condensation product of titanium hydroxide. After washing with distilled water, 10 cc of a 30% by mass hydrogen peroxide solution was added and stirred to obtain a yellow translucent viscous titanium-containing aqueous liquid T1 containing titanium.

Production Example 2 (Titanium-containing aqueous liquid T2)
A mixture of 10 parts by mass of tetraiso-propoxytitanium and 10 parts by mass of iso-propanol was dropped into a mixture of 30 parts by mass of 10 parts by mass of hydrogen peroxide and 100 parts by mass of deionized water with stirring at 20 ° C. over 1 hour. did. Thereafter, aging was carried out at 25 ° C. for 2 hours to obtain a yellow transparent, slightly viscous titanium-containing aqueous liquid T2.
Production Example 3 (Titanium-containing aqueous liquid T3)
A titanium-containing aqueous liquid T3 was obtained under the same production conditions as in Production Example 2 except that tetra-n-butoxy titanium was used instead of tetraiso-propoxy titanium used in Production Example 2.

Production Example 4 (Titanium-containing aqueous liquid T4)
In the same production conditions as in Production Example 2, except that a tetramer of tetraiso-propoxytitanium (low condensation product of tetraiso-propoxytitanium) was used instead of tetraiso-propoxytitanium used in Production Example 2, titanium was used. A contained aqueous liquid T4 was obtained.
Production Example 5 (Titanium-containing aqueous liquid T5)
A titanium-containing aqueous liquid was produced under the same production conditions as in Production Example 2, except that hydrogen peroxide was used in 3 times the amount of Production Example 2, dropped at 50 ° C over 1 hour, and further aged at 60 ° C for 3 hours. T5 was obtained.

Production Example 6 (Titanium-containing aqueous liquid T6)
The titanium-containing aqueous liquid T3 produced in Production Example 3 was further heat-treated at 95 ° C. for 6 hours to obtain a white yellow translucent titanium-containing aqueous liquid T6.
Production Example 7 (Titanium-containing aqueous liquid T7)
A mixture of 10 parts by mass of tetraiso-propoxytitanium and 10 parts by mass of iso-propanol, 5 parts by mass (solid content) of “TKS-203” (trade name, manufactured by Teika Co., Ltd.), 30% by mass hydrogen peroxide solution The mixture was added dropwise to a mixture of 10 parts by mass and 100 parts by mass of deionized water with stirring at 10 ° C. over 1 hour. Thereafter, the mixture was aged at 10 ° C. for 24 hours to obtain a yellow transparent, slightly viscous titanium-containing aqueous liquid T7.

[Zirconium compound (B)]
B1: Ammonium zirconium carbonate B2: Zirconium oxycarbonate B3: Zircon ammonium fluoride [Organic phosphate compound (C)]
C1: 1-hydroxymethane-1,1-diphosphonic acid C2: 1-hydroxyethane-1,1-diphosphonic acid

[Mixture of metal phosphate (D) and silicon oxide (E)]
A mixture in which silicon oxide (E) was added to an aqueous solution of metal phosphate (D) at a solid content ratio shown in Tables 2, 4 and 6 and vigorously stirred, and the silicon oxide was dispersed in the aqueous metal phosphate solution. Obtained. In addition, the comparative example of No. 34 and No. 35 of Table 4 contains only silicon oxide E1.
・ Metal phosphate (D)
D1: primary aluminum phosphate D2: primary magnesium phosphate D3: primary manganese phosphate / silicon oxide (E)
E1: Aerosil 300 (trade name, manufactured by Nippon Aerosil Co., Ltd., vapor phase silica, bulk specific gravity; 50 g / L)
E2: Aerosil 200 (trade name, manufactured by Nippon Aerosil Co., Ltd., vapor phase silica, bulk specific gravity; 35 g / L)
E3: Snowtex O (trade name, manufactured by Nissan Chemical Industries, colloidal silica)
E4: Aerosil 300CF (trade name, manufactured by Nippon Aerosil Co., Ltd., vapor phase silica, bulk specific gravity; 35 g / L)

[Vanadate compound (F)]
F1: Ammonium metavanadate F2: Sodium metavanadate [water-soluble or water-dispersible organic resin (G)]
G1: Superflex E-2500 (trade name, manufactured by Daiichi Kogyo Seiyaku Co., Ltd., water-based polyurethane resin, Tg: 42 ° C.)
G2: Bayronal MD-1100 (trade name, manufactured by Toyobo Co., Ltd., water-based polyester resin)
G3: Adeka Resin EM-0718 (trade name, manufactured by ADEKA, water-based epoxy resin)

As the base steel plate of the surface-treated steel plate, the plated steel plate shown in Table 1 was used.
The surface treatment composition in which the components (B) to (G) and distilled water are appropriately blended and mixed with the titanium-containing aqueous liquid (A) described above and the solid content is adjusted to 2 to 10 mass% is plated steel sheet. The sample was applied to the surface and dried to a predetermined drying temperature (maximum ultimate plate temperature) after 5 seconds to obtain a test material. In addition, the comparative example of No. 96 is a test material which performed the phosphate process. In this comparative example, as a pretreatment for the phosphate treatment, the surface of the zinc-based plated steel sheet was surface-treated with a surface conditioner (trade name “Plenpalen Z”, manufactured by Nihon Parkerizing Co., Ltd.), and then treated with zinc phosphate. A solution (trade name “PB3312M”, manufactured by Nihon Parkerizing Co., Ltd.) was used to perform a phosphate treatment so that the adhesion amount was 1.0 g / m ² .

These test materials were evaluated for heat discoloration resistance, water adhesion resistance, corrosion resistance and blackening resistance by the following test methods (1) to (4).
Furthermore, after applying a common adhesive for polyvinyl chloride film to the test material so that the dry film thickness becomes 3 μm, the furnace temperature is heated in a heating furnace having a temperature of 100 ° C., and then a polyvinyl chloride film having a film thickness of 250 μm is formed. A polyvinyl chloride film (organic resin layer) was adhered by thermocompression bonding with the roll pressed against the surface of the test material so that the steel sheet temperature was 230 ° C. Thus, about the test material which formed the organic resin layer, adhesiveness, the adhesiveness after immersion in boiling water, and corrosion resistance were evaluated by the test method of following (5)-(7).
Furthermore, the storage stability of the surface treatment composition was evaluated by the following test methods (8) and (9).
The above results are shown in Tables 2 to 9 together with the composition of the surface treatment composition applied to each specimen and the coating conditions.

(1) Heat-resistant discoloration The specimen was heated to a plate temperature of 500 ° C. in an infrared image furnace in 30 seconds, held for 30 seconds, and then visually observed on the surface appearance when allowed to cool naturally to room temperature. The evaluation criteria are as follows.
○: No discoloration △: Discoloration to pale yellow ×: Discoloration from yellow to brown (2) Adhesion to water The appearance of the surface when 1 mL of pure water was dropped onto the test material and dried in an oven at 100 ° C. for 10 minutes. Visual observation was performed. The evaluation criteria are as follows.
◎: No change ○: Almost no change △: Only the outline of the dropping part is observed ×: The whole dropping part is discolored

(3) Corrosion resistance A salt spray test of JIS-Z-2371-2000 was performed on the test material with the end and the back surface tape-sealed, and the test time at which the white rust generation area ratio was 5% was measured. The evaluation criteria are as follows.
◎: 36 hours or more ○: 24 hours or more, less than 36 hours △: 12 hours or more, less than 24 hours ×: Less than 12 hours (4) Blackening resistance The test material is controlled to an atmosphere of 80 ° C. and 95% relative humidity. The change in whiteness (L value) when left in a constant temperature and humidity chamber for 24 hours was calculated by ΔL (L value after test−L value before test). The evaluation criteria are as follows.
○: ΔL ≧ −5.0
Δ: −5.0> ΔL ≧ −10.0
×: −10.0> ΔL

(5) Adhesion In accordance with the adhesion test (Eriksen test) described in JIS-K-6744-1992 (polyvinyl chloride-coated metal plate), a test piece of 90 mm × 90 mm cut out from the test material was used. Thus, the adhesion of the organic resin layer was examined. In this adhesion test, after pushing in with an Erichsen height of 6 mm and a cut portion length of 50 mm, the state of peeling of the organic resin layer was visually observed and evaluated according to the following criteria.
◎: No peeling ○: Part of the cut edge is slightly peeled (within 1 mm from the cut)
X: The film is largely peeled at the edge of the cut part (exceeding 1 mm from the cut)
(6) Adhesion after immersion in boiling water Except that the test piece was immersed in boiling ion exchange water for 1 hour before the adhesion test, the same method as “(5) Adhesion” above. An adhesion test was conducted and evaluated according to the following criteria.
◎: No peeling ○: Part of the cut edge is slightly peeled (within 1 mm from the cut)
X: The film is largely peeled at the edge of the cut part (exceeding 1 mm from the cut)

(7) Corrosion resistance (after coating with organic resin layer)
It is a method according to the description of the corrosion resistance section of JIS-K-6744-1992, using a test piece of 50 mm × 100 mm cut out from the test material, and in accordance with the provisions of JIS-Z-2371-2000 The spray test was conducted for 1000 hours. In this test, a part of the end face of each test piece was exposed, and evaluation was performed according to the following criteria according to the degree of swelling of the organic resin layer from the edge.
◎: Swelling width from edge (maximum value) less than 15 mm ○: Swelling width from edge (maximum value) 15 mm or more and less than 25 mm △: Swelling width from edge (maximum value) 25 mm or more and less than 35 mm ×: From edge Swollen width (maximum value) 35mm or more

(8) Storage stability (I)
The surface treatment composition having a solid content of 8 mass% was aged at 40 ° C. for 2 weeks, and the solid precipitation state and viscosity were visually evaluated. The evaluation criteria are as follows.
◎: No solid content precipitation and no change in viscosity ○: Slight solid content precipitation or small viscosity change △: Many solid content precipitations or large viscosity change ×: Many solid content precipitations Large change in viscosity (9) Storage stability (II)
The surface treatment composition having a solid content of 8 mass% was maintained at 30 ° C., and the precipitation state of the solid content was visually evaluated every week. The evaluation criteria are as follows.
◎: No precipitation after 4 weeks ○: Precipitation occurs after 4 weeks △: Precipitation occurs after 2 to 3 weeks ×: Precipitation occurs after 1 week

In Table 2, Table 4, Table 6, and Table 8, * 1 to * 11 indicate the following contents.
* 1 Plated steel sheets No. 1 to No. 9 listed in Table 1
* 2 Titanium-containing aqueous liquids T1 to T7 described in the specification text
* 3 Zirconium compounds B1 to B3 described in the specification text
* 4 Organophosphate compounds C1 to C3 described in the specification text
* 5 Metal phosphates D1 to D3 described in the specification text
* 6 Silicon oxides E1 to E4 described in the specification text
* 7 Vanadate compounds F1, F2 described in the main text of the specification
* 8 Water-soluble or water-dispersible organic resins G1 to G3 described in the specification text
* 9 Solid content mass (g) in 1 liter of surface treatment composition (aqueous treatment liquid)
* 10 Ratio of the surface treatment composition (aqueous treatment liquid) in the total solid content (mass%)
* 11 Mass ratio of solid content

Claims (8)

Titanium obtained by mixing at least one titanium compound selected from hydrolyzable titanium compounds, low-condensates of hydrolyzable titanium compounds, titanium hydroxide, and low-condensates of titanium hydroxide with hydrogen peroxide water 10 to 300 parts by mass of the zirconium carbonate compound (B) and 50 to 200 parts by mass of the organic phosphate compound (C) are contained with respect to 100 parts by mass of the solid content of the aqueous solution (A). The salt (D) is contained in a proportion of 5 to 20 mass% in the total solid content of the surface treatment composition, and the silicon oxide (E) is contained in a proportion of 10 to 50 mass% in the total solid content of the surface treatment composition , and A surface treatment composition for a zinc-based plated steel sheet or an aluminum-based plated steel sheet, which does not contain hexavalent chromium (excluding hexavalent chromium as an inevitable impurity) . Furthermore, 1-400 mass parts of vanadic acid compounds (F) are contained with respect to 100 mass parts of solid content of a titanium containing aqueous liquid (A), The galvanized steel plate or aluminum type | system | group of Claim 1 characterized by the above-mentioned. Surface treatment composition for plated steel sheet . The water-soluble organic resin and / or the water-dispersible organic resin (G) is further contained in an amount of 1 to 10 mass% in the total solid content of the surface treatment composition. Surface treatment composition for zinc-based plated steel sheet or aluminum-based plated steel sheet . Solid content mass ratio (D) / (E) of metal phosphate (D) and silicon oxide (E) is 50/50 to 10/90, Any one of Claims 1-3 characterized by the above-mentioned. The surface treatment composition for galvanized steel sheet or aluminum-based galvanized steel sheet described in the paragraph. The surface treatment composition for a zinc-based plated steel sheet or an aluminum-based plated steel sheet according to any one of claims 1 to 4, wherein the silicon oxide (E) is a vapor phase silica produced by a dry process. . 6. The surface treatment composition for a zinc-based plated steel sheet or an aluminum-based plated steel sheet according to claim 5, wherein the bulk specific gravity of the vapor phase silica is 40 g / L or less. The coating amount formed by applying and drying the surface treatment composition according to any one of claims 1 to 6 on the surface of a zinc-based plated steel sheet or an aluminum-based plated steel sheet is 0.03 to 2. A surface-treated steel sheet having a surface-treated film of 0.0 g / m ² .   An organic resin-coated steel sheet comprising an organic resin layer on the surface-treated film of the surface-treated steel sheet according to claim 7.