JP5156250B2 - Surface-treated steel sheet with excellent corrosion resistance, electrical conductivity, and abrasion resistance - Google Patents

Description

  The present invention relates to a surface-treated steel sheet that is optimal for applications such as automobiles, home appliances, and building materials, and particularly relates to an environmentally-friendly surface-treated steel sheet that does not contain any pollution-controlling substances such as hexavalent chromium in the film.

  Conventionally, for steel sheets for automobiles, steel sheets for household appliances, and steel sheets for building materials, hexavalent chromium is used for the purpose of improving corrosion resistance (white rust resistance, red rust resistance) on the surface of zinc-plated steel sheets or aluminum-based plated steel sheets. Steel plates that have been subjected to chromate treatment with a treatment liquid containing as a main component have been widely used. However, since chromate treatment uses hexavalent chromium, which is a pollution-controlling substance, recently there has been a movement to regulate its use. On the other hand, instead of chromate treatment, surface treatment technology that does not use hexavalent chromium at all is used. Development is actively underway. Among these, several techniques using an organic compound or an organic resin have been proposed, and examples include the following.

(1) Technology for forming a film from an aqueous resin composition obtained by reacting an epoxy resin with a hydrazine derivative having active hydrogen, a surface treatment composition containing a silane coupling agent, phosphoric acid, and the like (for example, Patent Document 1)
(2) A resin composition in which a composite oxide film containing fine oxide particles, phosphoric acid and a specific metal is formed as a lower layer, and an hydrazine derivative having active hydrogen is reacted with an organic resin such as an epoxy resin on the upper layer. Of forming an organic film with a coating composition containing a rust preventive additive and a specific anticorrosive additive (for example, Patent Document 2)
(3) Technology for forming a lower layer film composed of a titanium compound, an organic phosphate compound, a water-soluble resin, a vanadate and a zirconium salt, and forming a fingerprint-resistant film on the upper layer (for example, Patent Document 3)
In order to improve the curability of the epoxy resin constituting the organic film, the following techniques have been proposed.
(4) Technology for introducing a basic nitrogen atom and a primary hydroxyl group at the end of an epoxy resin (for example, Patent Document 4)

  In particular, in the field of home appliances in recent years, there are an increasing number of cases in which steel plates are used without coating for the purpose of saving process and cost. In such a usage pattern, in order to satisfy various performance requirements regarding the surface appearance, a coated metal plate in which an organic composite film based on a special resin is formed on a steel plate has been developed. The surface-treated steel sheet with such an organic composite film may cause abrasion due to rubbing with corrugated cardboard or the like during product transportation. Significantly reduce the commercial value.

In order to improve the abrasion resistance, the following techniques have been proposed.
(5) Technology for melting the lubricant simultaneously with the baking of the film and protecting the film surface with the lubricant (for example, Patent Document 5)
(6) Technology for projecting a lubricant on the surface of the film and using the lubricant as a spacer (for example, Patent Documents 6 and 7)
JP 2003-105554 A JP 2002-53979 A JP 2006-22370 A JP-A-7-118870 JP 2001-288484 A JP 2002-212749 A JP-A-8-207199

However, these conventional techniques have the following problems.
First, in the techniques (1) and (2), a dense organic polymer film (barrier layer) is formed by imparting a hydrazine derivative to an epoxy resin, thereby imparting desired corrosion resistance. Further, the barrier property is enhanced by crosslinking using a curing agent such as polyisocyanate. However, since the hydroxyl group of the epoxy resin that crosslinks with the curing agent is a secondary hydroxyl group, a sufficient crosslinking density cannot be obtained due to steric hindrance with the resin skeleton, and the corrosion resistance is insufficient.

On the other hand, although the technique (3) can provide a certain degree of corrosion resistance by the lower layer film, the corrosion resistance of the upper layer fingerprint-resistant film is low, so that the overall corrosion resistance is insufficient.
In the technique (4), the terminal epoxy group is modified with alkanolamine to introduce a basic nitrogen atom and a primary hydroxyl group, thereby improving the adhesion and curability of the epoxy resin. However, the organic film formed by such a technique does not sufficiently exhibit the adhesion due to the basic nitrogen atom of the alkanolamine in the chromium-free film, and the corrosion resistance is insufficient.
In addition, since the technologies (5) and (6) provide abrasion resistance with a specific lubricant, applicable lubricants are limited, and it is difficult to design lubrication characteristics required during processing. is there.

  Accordingly, an object of the present invention is to solve such problems of the prior art, and to obtain excellent corrosion resistance without containing a pollution control substance such as hexavalent chromium in the film, and also relates to the type of lubricant to be applied. Another object of the present invention is to provide a surface-treated steel sheet that has excellent abrasion resistance and excellent electrical conductivity.

  As a result of intensive studies by the present inventors in order to solve the above-mentioned problems, an organic phosphate compound, a vanadic acid compound, a specific titanium-based aqueous liquid on the surface of a zinc-based plated steel sheet or an aluminum-based plated steel sheet, A surface treatment film is formed by a surface treatment composition in which a zirconium fluoride compound and a zirconium carbonate compound are added in a predetermined ratio, and an epoxy resin having a primary hydroxyl group in the resin is further formed on the epoxy resin having a primary hydroxyl group in the resin. It has been found that very excellent corrosion resistance and abrasion resistance can be obtained by forming an upper film with a coating composition containing a curing agent and a solid lubricant.

（式中、Ｒ＝ＨまたはＣＨ _３ 、ｎは３〜６）
水酸基と架橋する基を有する硬化剤（Ｈ）と、固形潤滑剤（Ｉ）を含有し、エポキシ樹脂（Ｇ）と硬化剤（Ｈ）の固形分質量比（Ｇ）／（Ｈ）が９５／５〜５５／４５、固形潤滑剤（Ｉ）の含有量がエポキシ樹脂（Ｇ）と硬化剤（Ｈ）の固形分の合計１００質量部に対して固形分の割合で１〜８０質量部である塗料組成物（Ｙ）を塗布し、乾燥することにより形成された膜厚が０．１〜５μｍの上層皮膜を有することを特徴とする耐食性、導電性および耐アブレージョン性に優れた表面処理鋼板。 The present invention has been made on the basis of such knowledge and has the following gist.
[1] At least one selected from a hydrolyzable titanium compound, a hydrolyzable titanium compound low-condensate, titanium hydroxide, and a titanium hydroxide low-condensate on the surface of a zinc-based plated steel sheet or an aluminum-based plated steel sheet 1-hydroxymethane-1,1-diphosphonic acid, 1-hydroxyethane-1 with respect to 100 parts by mass of the solid content of the titanium-containing aqueous liquid (A) obtained by mixing a seed titanium compound with aqueous hydrogen peroxide. , 1-diphosphonic acid, 1-hydroxypropane-1,1-diphosphonic acid, 2-hydroxyphosphonoacetic acid, 2-phosphonobutane-1,2,4-tricarboxylic acid, and salts thereof, or 1 to 400 parts by mass of two or more organic phosphoric acid compounds (B), vanadic acid, lithium orthovanadate, sodium orthovanadate, metavanadate 1 to 400 parts by mass of one or more vanadate compounds (C) selected from the group consisting of aluminum, potassium metavanadate, sodium metavanadate, ammonium metavanadate, sodium pyrovanadate, vanadyl chloride and vanadyl sulfate, zirconium fluoride 1 to 400 parts by mass of one or more zirconium fluoride compounds (D) selected from sodium, potassium, lithium and ammonium salts of hydrofluoric acid, sodium carbonate and potassium salts of zirconium carbonate, A film formed by applying and drying a surface treatment composition (X) containing 1 to 400 parts by mass of one or more zirconium carbonate compounds (E) selected from lithium salts and ammonium salts thickness having a surface treated film of 0.01 to 1.0 [mu] m, to the upper layer, epoxy resin The cyclic ester compound (g2) represented by (g1) and the following formula (2) is converted into [number of moles of epoxy resin (g1)] / [number of moles of cyclic ester compound (g2)] = 0.05 to 0.5. An epoxy resin (G) having a primary hydroxyl group in the resin, obtained by reacting under the conditions :

(In the formula, R = H or CH ₃ , n is 3 to 6)
It contains a curing agent (H) having a group that crosslinks with a hydroxyl group and a solid lubricant (I), and the solid content mass ratio (G) / (H) of the epoxy resin (G) and the curing agent (H) is 95 / 5 to 55/45, the content of the solid lubricant (I) is 1 to 80 parts by mass with respect to the total solids of 100 parts by mass of the epoxy resin (G) and the curing agent (H). A surface-treated steel sheet excellent in corrosion resistance, electrical conductivity and abrasion resistance, characterized in that it has an upper film with a thickness of 0.1 to 5 μm formed by applying and drying the coating composition (Y).

[2] In the surface-treated steel sheet according to [1], the surface treatment composition (X) further contains a water-soluble organic resin and / or a water-dispersible organic resin (F) in the solid content of the titanium-containing aqueous liquid (A). A surface-treated steel sheet excellent in corrosion resistance, conductivity and abrasion resistance, characterized by containing 2000 parts by mass or less with respect to 100 parts by mass.
[3] In the surface-treated steel sheet according to [1] or [2], the epoxy resin (G) is an epoxy resin in which an epoxy group is modified with an active hydrogen-containing compound, and a part of the active hydrogen-containing compound or A surface-treated steel sheet excellent in corrosion resistance, conductivity and abrasion resistance, characterized in that all are hydrazine derivatives having active hydrogen.

[4] In the surface-treated steel sheet according to any one of [1] to [3], the coating composition (Y) is further added with one or more rust prevention additives selected from the following (a) to (e): The component (J) contains 1 to 100 parts by mass of the solid content with respect to 100 parts by mass in total of the solids of the epoxy resin (G) and the curing agent (H). A surface-treated steel sheet with excellent abrasion resistance.
(A) Phosphate (b) Ca ion exchange silica (c) Molybdate (d) Silicon oxide (e) One or more selected from triazoles, thiols, thiadiazoles, thiazoles, thiurams Organic compounds

  The surface-treated steel sheet of the present invention provides excellent corrosion resistance without containing pollution control substances such as hexavalent chromium in the film, and excellent abrasion resistance regardless of the type of lubricant to be applied. Moreover, it is excellent also in electroconductivity.

The details of the present invention and the reasons for limitation will be described below.
Examples of the zinc-based plated 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 plating Steel plate (for example, Zn-5% Al alloy-plated steel plate, Zn-55% Al alloy-plated steel plate), Zn-Mg alloy-plated steel plate, Zn-Al-Mg alloy-plated steel plate (for example, Zn-6% Al-3% Mg) Alloy-plated steel sheet, Zn-11% Al-3% Mg alloy-plated steel sheet), and further, metal oxides, polymers, etc. are separated in the plating film of these plated steel sheets. And zinc-based composite-plated steel sheet (for example, Zn-SiO ₂ dispersion plating steel plate) or the like can be used.

In addition, among the above-described plating, a multi-layer plated steel sheet in which two or more layers of the same type or different types are plated 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 plated in advance with thinning such as Ni, and the above-described various plating may be performed thereon.
As a plating method, any feasible method such as an electrolytic method (electrolysis in an aqueous solution or electrolysis in a non-aqueous solvent), a melting method, a gas phase method, or the like may be adopted.
Furthermore, in order to prevent blackening of the plating, about 1 to 2000 ppm of one or more trace elements of Ni, Co, and Fe are deposited in the plating film, or one of Ni, Co, and Fe is deposited on the surface of the plating film. You may make it precipitate these elements by performing the surface adjustment process by the alkaline aqueous solution or acidic aqueous solution containing the above.

Next, the surface treatment film formed as the first layer film and the surface treatment composition for forming this film on the surface of the zinc-based plated steel sheet or the aluminum-based plated steel sheet will be described.
In the surface-treated steel sheet of the present invention, the surface-treated film formed on the surface of the zinc-based plated steel sheet or the aluminum-based plated steel sheet is composed of a specific titanium-containing aqueous liquid (A), organic phosphoric acid compound (B), vanadic acid compound ( C), a surface treatment composition (X) containing a zirconium fluoride compound (D) and a zirconium carbonate compound (E) as essential components is applied and dried. This surface treatment film does not contain chromium (except for chromium as an inevitable impurity).
The reason why excellent corrosion resistance can be obtained by forming such a surface-treated film is not necessarily clear, but a mixed solution in which a specific metal salt is combined with a specific titanium-based aqueous liquid is dried on the steel sheet surface. In this process, it is considered that a film having a high corrosion-inhibiting ability is formed by the formation of a composite salt by the contained metal ions and precipitation of a titanium oxide-based dense film component.

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. When the condensation degree exceeds 30, a white precipitate is formed when mixed with hydrogen peroxide, and a stable titanium-containing aqueous liquid cannot be obtained.
The hydrolyzable titanium compounds listed above, low-condensates of hydrolyzable 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.

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 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 resulting 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 liquid containing ultrafine particles of crystallized titanium oxide is obtained. When the heat treatment or autoclave treatment is less than 80 ° C., crystallization of titanium oxide does not proceed sufficiently. The titanium oxide dispersion thus produced has an average particle diameter of titanium oxide ultrafine particles of 10 nm or less, preferably about 1 to 6 nm. When the average particle diameter of the titanium oxide ultrafine particles is larger than 10 nm, the film forming property is deteriorated (when the film is dried after coating to form a film, cracking occurs at a film thickness of 1 μm or more), which is not preferable. 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).

By applying and drying the surface treatment composition (X ₀ ) containing the titanium-containing aqueous liquid (A) using the hydrolyzable titanium compound a on the surface of the plated steel sheet (for example, heat drying at a low temperature), the surface treatment composition (X ₀ ) A dense titanium oxide-containing film (surface treatment film) having excellent adhesion can be formed.
The heating temperature after applying the surface treatment composition (X ₀ ) is, for example, preferably 200 ° C. or lower, particularly preferably 150 ° C. or lower. ) Of titanium oxide-containing film can be formed.
Moreover, 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), only the surface treatment composition (X ₀ ) is applied. Since a crystalline titanium oxide-containing film can be formed, 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 (ii), 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 CORPORATION, anatase crystal form, average particle diameter 6 nm), TA-15 (trade name, manufactured by NISSAN CHEMICAL CO., LTD., 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 less than 1/99, the effect of adding the titanium oxide sol cannot be sufficiently obtained in terms of stability, photoreactivity, etc. On the other hand, if it exceeds 99/1, the film forming property is inferior. Absent.

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 subjected to a heat treatment or autoclave treatment 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).

Like the titanium-containing aqueous liquid (A) using the hydrolyzable titanium compound a described above, the surface treatment composition (X ₀ ) containing the titanium-containing aqueous liquid (A1) is applied to the surface of the plated steel sheet and dried ( For example, by performing heat drying at a low temperature, a dense titanium oxide-containing film (surface treatment film) having excellent adhesion can be formed.
The heating temperature after applying the surface treatment composition (X ₀ ) is, for example, preferably 200 ° C. or less, particularly preferably 150 ° C. or less. By heating and drying at such a temperature, anatase-type titanium oxide containing some hydroxyl groups. A contained 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 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 the hydrogen peroxide solution is less than 0.1 parts by mass in terms of hydrogen peroxide, chelate formation is not sufficient and white turbid precipitation occurs. On the other hand, if it exceeds 100 parts by mass, unreacted hydrogen peroxide tends to remain, and dangerous active oxygen is released during storage, which is not preferable.

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, silica, 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 (X) is 1 to 100 g / L, preferably 5 to 50 g / L in terms of solid content. It is preferable from the point.

  Examples of the organic phosphate compound (B) include 1-hydroxymethane-1,1-diphosphonic acid, 1-hydroxyethane-1,1-diphosphonic acid, 1-hydroxypropane-1,1-diphosphonic acid, and the like. Suitable examples include hydroxyl group-containing organic phosphorous acid; carboxyl group-containing organic phosphorous acid such as 2-hydroxyphosphonoacetic acid, 2-phosphonobutane-1,2,4-tricarboxylic acid, and salts thereof. These 1 type (s) or 2 or more types can be used.

The organic phosphoric acid compound (B) has a large effect of improving the storage stability of the titanium-containing aqueous liquid (A). Among them, 1-hydroxyethane-1,1-diphosphonic acid has a particularly large effect. These are particularly preferably used.
The compounding amount of the organic phosphoric acid compound (B) is 1 to 400 parts by mass, particularly 20 to 300 parts by mass with respect to 100 parts by mass of the solid content of the titanium-containing aqueous liquid (A). To preferred. If the amount of the organic phosphoric acid compound (B) exceeds 400 parts by mass with respect to 100 parts by mass of the solid content of the titanium-containing aqueous liquid (A), the water adhesion resistance is inferior.

The vanadate compound (C) improves the anticorrosive property of the film obtained by the surface treatment composition. For example, vanadate, lithium orthovanadate, sodium orthovanadate, lithium metavanadate, potassium metavanadate, Examples thereof include sodium metavanadate, ammonium metavanadate, sodium pyrovanadate, vanadyl chloride, and vanadyl sulfate. One or more of these can be used. Among these, metavanadate having a large effect on corrosion resistance is preferable, and ammonium metavanadate is particularly preferable.
The amount of the vanadic acid compound (C) is 1 to 400 parts by weight, particularly 10 to 400 parts by weight, based on 100 parts by weight of the solid content of the titanium-containing aqueous liquid (A). It is preferable from the viewpoint of the corrosion resistance. When the compounding amount of the vanadic acid compound (C) exceeds 400 parts by mass with respect to 100 parts by mass of the solid content of the titanium-containing aqueous liquid (A), the corrosion resistance after alkali degreasing is inferior.

Examples of the zirconium fluoride compound (D) include salts of zirconium hydrofluoric acid such as sodium, potassium, lithium, and ammonium, and one or more of these can be used. Of these, ammonium zirconium fluoride is preferable from the viewpoint of water-resistant adhesion.
The blending amount of the zirconium fluoride compound (D) is 1 to 400 parts by mass, particularly 20 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 blending amount of the zirconium fluoride compound (D) exceeds 400 parts by mass with respect to 100 parts by mass of the solid content of the titanium-containing aqueous liquid (A), the corrosion resistance after alkali degreasing is inferior.

Examples of the zirconium carbonate compound (E) include salts of zirconium carbonate such as sodium, potassium, lithium, and ammonium, and one or more of these can be used. Of these, ammonium zirconium carbonate is preferable from the viewpoint of water-resistant adhesion.
The compounding amount of the zirconium carbonate compound (E) 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 the corrosion resistance. When the compounding quantity of a zirconium carbonate compound (E) exceeds 400 mass parts with respect to 100 mass parts of solid content of a titanium containing aqueous liquid (A), since the corrosion resistance after carrying out alkali degreasing is inferior, it is unpreferable.

The surface treatment composition (X) used in the present invention can further contain a water-soluble organic resin and / or a water-dispersible organic resin (F) as necessary, thereby improving paintability.
This water-soluble organic resin and / or water-dispersible organic resin (F) 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 is known. 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 may be converted to acidic compounds (such as carboxyl group-containing resins) with amine compounds such as ethanolamine and triethylamine; 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, phenol 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, in particular, the storage stability of the surface treatment composition (X) is obtained by using at least one organic resin selected from water-soluble or water-dispersible acrylic resins, urethane resins and epoxy resins. In view of the above, it is particularly preferable to use a water-soluble or water-dispersible acrylic resin as a main component from the viewpoint of the balance between the storage stability of the surface treatment composition (X) and the coating film performance.

A water-soluble or water-dispersible acrylic resin is synthesized by a conventionally known method, for example, an emulsion polymerization method, a suspension polymerization method, or a polymer having a hydrophilic group by solution polymerization. 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 obtained by copolymerizing styrene from the viewpoint of corrosion resistance and the like. 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 and 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 resin include a chain extender that is a low molecular weight compound having two or more active hydrogens such as a diol and a diamine, if necessary, and a polyurethane comprising a polyol and a diisocyanate such as a polyester polyol and a 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 or sodium bisulfite is forcibly submerged in water using an emulsifier and mechanical shearing force. 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, as the polyurethane resin, those obtained by different methods among the above-described dispersion or dissolution methods can be mixed and used.

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 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 HW-330, HW-340, HW-350 (both trade names, manufactured by Dainippon Ink and Chemicals), Superflex 100, 150, E-2500, F-3438D (all are trade names, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.).

  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 suitably 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 with a secondary mono- or polyamine having a ketiminated primary amino group (see, for example, US Pat. No. 4,017,438); having an epoxy compound and a primary amino group ketiminated Examples include etherification reaction products with hydroxyl compounds (see, for example, JP-A-59-43013).

  The epoxy resin preferably has 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. 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 water-dispersible organic resin (F) is 2000 parts by mass or less, particularly 5 to 1500 parts by mass with respect to 100 parts by mass of the solid content of the titanium-containing aqueous liquid (A). Is preferred from the standpoint of corrosion resistance after alkaline degreasing. When the blending amount of the water-soluble organic resin and / or water-dispersible organic resin (F) exceeds 2000 parts by mass with respect to 100 parts by mass of the solid content of the titanium-containing aqueous liquid (A), the corrosion resistance after alkali degreasing is reduced. Since it is inferior, it is not preferable.

A silane coupling agent can be further added to the surface treatment composition (X) as necessary. Examples of the silane coupling agent include N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, N- β (N-vinylbenzylaminoethyl) γ-aminopropyltrimethoxysilane hydrochloride, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopyrrolotrimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, methyltrimethoxy Silane, vinyltriacetoxysilane, γ-chloropropyltrimethoxysilane, hexamethyldisilazane, γ-anilinopropyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, octadecyldimethyl [3- (trimethoxysilane Yl) propyl] ammonium chloride, trimethylchlorosilane, and the like, and one or more of these may be used.
The compounding amount of the silane coupling agent is 1 to 400 parts by weight, particularly 10 to 400 parts by weight, based on 100 parts by weight of the solid content of the titanium-containing aqueous liquid (A). From the point of view, it is preferable.

If necessary, organic fine particles and / or inorganic fine particles can be further added to the surface treatment composition (X). By adding such fine particles, the transparency of the coating film is lowered, and nitrite (interference color) that is likely to occur in a thin film can be suppressed, making it particularly suitable for applications in which appearance is important. The fine particles preferably have an average particle size of 3 to 1000 nm, particularly 3 to 500 nm, from the viewpoint of sedimentation stability and corrosion resistance of the particles.
Examples of the organic fine particles include resin fine particles such as acrylic, polyurethane, nylon, and polyethylene glycol. Examples of the inorganic fine particles include silica, titanium dioxide, barium sulfate, and calcium carbonate. From the viewpoint of cost, silica, titanium dioxide, barium sulfate and the like are particularly preferable.
The blending amount of the organic fine particles and / or inorganic fine particles is preferably 1 to 30% by mass, particularly 1 to 20% by mass in the solid content of the surface treatment composition (X) from the viewpoint of corrosion resistance and the like.

If necessary, the surface treatment composition (X) further includes an etching agent such as an inorganic phosphoric acid compound or hydrofluoric acid, a heavy metal compound other than the components specified by the present invention, an aqueous organic polymer compound, a thickener. , Surfactants, rust preventives (tannic acid, phytic acid, benzotriazole, etc.), colored pigments, extender pigments, silica, rust preventive pigments, and the like can be added.
The surface treatment composition (X) is usually diluted with water and used. If necessary, for example, a hydrophilic solvent such as methanol, ethanol, isopropyl alcohol, an ethylene glycol solvent, or a propylene glycol solvent. It may be diluted with.
Since the surface treatment composition (X) becomes a stable liquid in a neutral or acidic region, pH 1 to 7, particularly 1 to 5 is particularly preferable.
The film thickness of the surface treatment film formed by the surface treatment composition (X) is from 0.01 to 1.0 μm, preferably from 0.05 to 0.00 μm, from the viewpoints of economy and coating film performance, particularly corrosion resistance and adhesion. 8 μm. If the film thickness is less than 0.01 μm, sufficient corrosion resistance cannot be obtained. On the other hand, if it exceeds 1.0 μm, the white rust resistance, conductivity, and abrasion resistance after alkali degreasing are poor.

In the surface-treated steel sheet of the present invention, the upper film formed on the surface-treated film described above includes an epoxy resin (G) having a primary hydroxyl group in the resin, and a curing agent (H) having a group that crosslinks the hydroxyl group. The film is formed by applying and drying the coating composition (Y) containing the solid lubricant (I). This film also does not contain chromium (except for chromium as an inevitable impurity).
The epoxy resin (G) constituting the coating composition (Y) is not particularly limited as long as it has a primary hydroxyl group in the resin. Such an epoxy resin (G) can be obtained, for example, by reacting the cyclic ester compound (g2) with the epoxy resin (g1).

上記化学構造式中、ｑは０〜５０の整数、好ましくは１〜４０の整数、特に好ましくは２〜２０の整数である。 The epoxy resin (g1) has a number average molecular weight of 1500 to 50000, preferably 2000 to 4000, which is obtained by reacting a polyphenol such as bisphenol A or bisphenol F with an epihalohydrin such as epichlorohydrin to introduce an epoxy group. A bisphenol type epoxy resin having an equivalent weight of 750 to 7500, preferably 2000 to 5000 is preferable. From the viewpoint of the corrosion resistance of the organic film obtained, an epoxy of the following formula (1) which is a reaction product of bisphenol A and epihalohydrin is used. Resins are particularly preferred.

In said chemical structural formula, q is an integer of 0-50, Preferably it is an integer of 1-40, Most preferably, it is an integer of 2-20.

  Examples of commercially available epoxy resin (g1) include jER828 (epoxy equivalent of about 190, number average molecular weight of about 350), jER834 (epoxy equivalent of about 250, number average molecular weight of about 470), jER1004 manufactured by Japan Epoxy Resin Co., Ltd. (Epoxy equivalent of about 950, number average molecular weight of about 1600), jER1007 (epoxy equivalent of about 2250, number average molecular weight of about 2900), jER1009 (epoxy equivalent of about 3250, number average molecular weight of about 3750), jER1010 (epoxy equivalent of about 4000, number average) Molecular weight of about 5500), Araldite AER6099 (epoxy equivalent of about 3500, number average molecular weight of about 3800) manufactured by Asahi Ciba, Epoxy R-309 (epoxy equivalent of about 3500, number average molecular weight of about 3800) manufactured by Mitsui Chemicals, Inc. Can be listed , All trade names).

（式中、Ｒ＝ＨまたはＣＨ_３、ｎは３〜６）
具体的には、δ−バレロラクトン、ε−カプロラクトン、ζ−エナラクトン、η−カプリロラクトン、γ−バレロラクトン、δ−カプロラクトン、ε−エナラクトン、ξ−カプリロラクトンなどが挙げられ、これらの１種または２種以上を用いることができる。また、これらのなかでも特に好ましいのは、ε−カプロラクトンである。
上記付加反応において、式（２）の環状エステル化合物（ｇ２）は開環し、エポキシ樹脂（ｇ１）中の二級水酸基と反応し、一級水酸基を付与することができる。 The cyclic ester compound (g2) to be reacted with the epoxy resin (g1) is represented by the following formula (2).

(In the formula, R = H or CH ₃ , n is 3 to 6)
Specific examples include δ-valerolactone, ε-caprolactone, ζ-enalactone, η-caprolactone, γ-valerolactone, δ-caprolactone, ε-enalactone, ξ-caprolactone, and the like. Species or two or more can be used. Of these, ε-caprolactone is particularly preferable.
In the above addition reaction, the cyclic ester compound (g2) of the formula (2) can open a ring and react with the secondary hydroxyl group in the epoxy resin (g1) to give a primary hydroxyl group.

Moreover, the terminal of the epoxy resin having a primary hydroxyl group may be an epoxy group, but it is obtained by modifying a part or all of the compound with an active hydrogen-containing compound which is a hydrazine derivative (g3) having active hydrogen. The corrosion resistance and conductivity of the film can be greatly improved.
Examples of the active hydrogen-containing compound that reacts with the epoxy group of the epoxy resin include those shown below, and one or more of these can be used, but at least a part of the active hydrogen-containing compound (preferably Are all hydrazine derivatives (g3) having active hydrogen.
・ Hydrazine derivatives with active hydrogen ・ Primary or secondary amine compounds with active hydrogen ・ Organic acids such as ammonia and carboxylic acids ・ Halogen halides such as hydrogen chloride ・ Alcohols and thiols ・ Having active hydrogen Quaternary chlorinating agent which is a mixture of hydrazine derivative or tertiary amine and acid

Specific examples of the hydrazine derivative (g3) having active hydrogen include the following.
(1) Carbohydrazide, propionic acid hydrazide, salicylic acid hydrazide, adipic acid dihydrazide, sebacic acid dihydrazide, dodecanoic acid dihydrazide, isophthalic acid dihydrazide, thiocarbohydrazide, 4,4'-oxybisbenzenesulfonylhydrazide, benzophenone hydrazone, aminopolyacrylamide Hydrazide compounds such as;
(2) pyrazole compounds such as pyrazole, 3,5-dimethylpyrazole, 3-methyl-5-pyrazolone, 3-amino-5-methylpyrazole;
(3) 1,2,4-triazole, 3-amino-1,2,4-triazole, 4-amino-1,2,4-triazole, 3-mercapto-1,2,4-triazole, 5-amino -3-mercapto-1,2,4-triazole, 2,3-dihydro-3-oxo-1,2,4-triazole, 1H-benzotriazole, 1-hydroxybenzotriazole (monohydrate), 6- Triazole compounds such as methyl-8-hydroxytriazolopyridazine, 6-phenyl-8-hydroxytriazolopyridazine, 5-hydroxy-7-methyl-1,3,8-triazaindolizine;

(4) tetrazole compounds such as 5-phenyl-1,2,3,4-tetrazole and 5-mercapto-1-phenyl-1,2,3,4-tetrazole;
(5) thiadiazole compounds such as 5-amino-2-mercapto-1,3,4-thiadiazole and 2,5-dimercapto-1,3,4-thiadiazole;
(6) Maleic hydrazide, 6-methyl-3-pyridazone, 4,5-dichloro-3-pyridazone, 4,5-dibromo-3-pyridazone, 6-methyl-4,5-dihydro-3-pyridazone, etc. Pyridazine compounds;
Among these, pyrazole compounds and triazole compounds having a 5-membered or 6-membered ring structure and having a nitrogen atom in the ring structure are particularly suitable. These hydrazine derivatives can be used individually by 1 type or in mixture of 2 or more types.

The reaction product of the epoxy resin (g1) and the cyclic ester compound (g2) is obtained by combining the epoxy resin (g1) and the cyclic ester compound (g2) at a temperature of 100 to 200 ° C., preferably 140 to 180 ° C. for 1 to 6 hours. An epoxy resin (G ₀ ) having a primary hydroxyl group can be obtained by reacting. Further, when the hydrazine derivative (g3) having active hydrogen is reacted, 40 parts of the active hydrogen-containing compound whose hydrazine derivative (g3) having a part or all of the active hydrogen in the epoxy resin (G ₀ ) is used. The reaction is carried out at a temperature of ˜200 ° C., preferably 80 ° C. to 130 ° C. for about 1 to 8 hours.

The blending ratio of the epoxy resin (g1), the cyclic ester compound (g2) and the hydrazine derivative (g3) having active hydrogen is preferably 5 to 20 mol% of the epoxy resin (g1) with respect to the total number of moles. More preferably 7-20 mol%, cyclic ester compound (g2) is preferably 40-90 mol%, more preferably 40-80 mol%, hydrazine derivative (g3) is preferably 10-40 mol%, more preferably It is suitable to set it as the range of 15-40 mol%. This is because the hydrazine derivative and the primary hydroxyl group in the resin skeleton are made to have an appropriate composition to balance corrosion resistance and reactivity.
In the production of the epoxy resin (G ₀ ), in particular, [number of moles of epoxy resin (g1)] / [number of moles of cyclic ester compound (g2)] = 0.05 to 0.5, preferably 0.1 to A range of 0.5, more preferably 0.1 to 0.25 provides a good balance between coating film hardness and reactivity, and a balance between corrosion resistance and reactivity.

  The above reaction may be performed by adding an organic solvent, and the type of the organic solvent to be used is not particularly limited. For example, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, dibutyl ketone, cyclohexanone; ethanol, butanol, 2-ethylhexyl alcohol, benzyl alcohol, ethylene glycol, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monohexyl ether , Propylene glycol, propylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether and other alcohols and ethers containing hydroxyl groups; ethyl acetate, butyl acetate, ethylene glycol monobutyl ether acetate and other esters; toluene, xylene Aromatic hydrocarbons etc. Illustration can, it is possible to use one or more of these. Of these, ketone-based or ether-based solvents are particularly preferable from the viewpoints of solubility with an epoxy resin and film-forming properties.

  In order to form a dense barrier film on the specific epoxy resin (G) as described above, a curing agent (H) having a group that crosslinks with a hydroxyl group is blended, and the film is heated and cured. The curing method for forming a film with the resin composition was selected from (1) a curing method using a urethanization reaction between isocyanate and a hydroxyl group in the base resin, and (2) melamine, urea and benzoguanamine. Etherification reaction between an alkyl etherified amino resin obtained by reacting one or more methylol compounds obtained by reacting formaldehyde with one or more monovalent alcohols having 1 to 5 carbon atoms and a hydroxyl group in the base resin. Among these, the curing method (1) is more preferable because it can form a dense film.

The polyisocyanate compound as a curing agent that can be used in the curing method (1) is an aliphatic, alicyclic (including heterocyclic) or aromatic isocyanate compound having at least two isocyanate groups in one molecule. Or a compound obtained by partially reacting these compounds with a polyhydric alcohol. Examples of such polyisocyanate compounds include the following.
(I) m- or p-phenylene diisocyanate, 2,4- or 2,6-tolylene diisocyanate, o- or p-xylylene diisocyanate, hexamethylene diisocyanate, dimer acid diisocyanate, isophorone diisocyanate (ii) above (i) Or a mixture thereof and a polyhydric alcohol (dihydric alcohols such as ethylene glycol and propylene glycol; trihydric alcohols such as glycerin and trimethylolpropane; tetrahydric alcohols such as pentaerythritol; sorbitol, dipentaerythritol, etc. A compound of at least two isocyanates in one molecule. These polyisocyanate compounds may be used alone or in combination of two or more. It can be.

Moreover, as a protective agent (blocking agent) of a polyisocyanate compound, for example,
(1) Aliphatic monoalcohols such as methanol, ethanol, propanol, butanol, octyl alcohol;
(2) ethylene glycol and / or diethylene glycol monoethers, for example, monoethers such as methyl, ethyl, propyl (n-, iso), butyl (n-, iso, sec);
(3) Aromatic alcohols such as phenol and cresol;
(4) oximes such as acetooxime and methyl ethyl ketone oxime;
A polyisocyanate compound that is stably protected at least at room temperature can be obtained by reacting one or more of these with the polyisocyanate compound.

  The mixing ratio of the curing agent (H) is 95/5 to 55/45, preferably 90/10 to 65/35, in terms of the mass ratio (G) / (H) of the solid content with the epoxy resin (G). If the amount of the curing agent (H) is too large, the performance of the film tends to deteriorate. For example, when a polyisocyanate compound is used as a curing agent, the polyisocyanate compound has water absorption, and if the blending amount is too large, the adhesion of the organic film is deteriorated. Furthermore, the unreacted polyisocyanate compound moves into the upper layer coating film such as electrodeposition coating, which causes inhibition of curing of the upper layer coating film and poor adhesion.

The epoxy resin is sufficiently crosslinked by the addition of the crosslinking agent (curing agent) as described above, but it is desirable to use a known curing accelerating catalyst in order to further increase the low temperature crosslinking property. Examples of the curing accelerating catalyst include N-ethylmorpholine, dibutyltin dilaurate, cobalt naphthenate, stannous chloride, zinc naphthenate, and bismuth nitrate.
For the purpose of slightly improving physical properties such as adhesion, a known resin such as acrylic, alkyd, or polyester can be mixed and used together with an epoxy resin. The mixing amount is 100 parts by mass or less, preferably 50 parts by mass or less with respect to 100 parts by mass of the solid content of the epoxy resin (G). When the mixing amount exceeds 100 parts by mass, the performance such as corrosion resistance tends to deteriorate.

  In order to further improve the abrasion resistance of the upper layer film, the upper layer film (coating composition (Y) for film formation) is blended with a solid lubricant (I). In the present invention, the means for imparting abrasion resistance to the film is not a specific solid lubricant as in the prior art described above, but by a crosslinking reaction between the primary hydroxyl group of the epoxy resin (G) and the curing agent (H). It is to form a dense and strong film to be generated. Therefore, the solid lubricant that can be used in the present invention is not particularly limited, and known ones can be applied. Examples thereof include the following, and one or more of these can be used.

(1) Polyolefin wax, paraffin wax: For example, polyethylene wax, synthetic paraffin, natural paraffin, micro wax, chlorinated hydrocarbon, etc. (2) Fluororesin fine particles: For example, polyfluoroethylene resin (polytetrafluoroethylene resin, etc.) In addition to these, fatty acid amide compounds (for example, stearic acid amide, palmitic acid amide, methylene bisstearamide, ethylene bisstearamide, oleic acid amide, esyl) Acid amides, alkylene bis-fatty acid amides), metal soaps (eg, calcium stearate, lead stearate, calcium laurate, calcium palmitate), metal sulfides (eg, molybdenum disulfide, tungsten disulfide, etc.) Etc.), graphite, fluorinated graphite, boron nitride, polyalkylene glycols may be used alone or in combinations of two or more such alkali metal sulfate.

Among the above solid lubricants, polyethylene wax and fluororesin fine particles (in particular, polytetrafluoroethylene resin fine particles) are preferable.
Examples of the polyethylene wax include Clariant Japan Co., Ltd. Selidust 9615A, Selidust 3715, Selidust 3620, Selidust 3910 (all are trade names), Sanyo Chemical Co., Ltd. Sun Wax 131-P, Sun Wax 161 -P (all are trade names), Chemipearl W-100, Chemipearl W-200, Chemipearl W-500, Chemipearl W-800, Chemipearl W-950 (all are trade names) manufactured by Mitsui Chemicals, Inc. Etc. can be used.

The fluororesin fine particles are most preferably tetrafluoroethylene fine particles. For example, Lubron L-2 and Lubron L-5 (all are trade names) manufactured by Daikin Industries, Ltd., Mitsui DuPont Fluorochemical Co., Ltd. ) MP1100, MP1200 (all are trade names), Asahi Glass Co., Ltd. full-on dispersion AD1, full-on dispersion AD2, full-on L141J, full-on L150J, and full-on L155J (all are trade names) are preferable. It is.
Among these, a particularly excellent lubricating effect can be expected by the combined use of polyolefin wax and tetrafluoroethylene fine particles.
The blending amount of the solid lubricant (I) is 1 to 80 parts by mass, preferably 3 to 40 parts by mass, based on 100 parts by mass of the total solids of the epoxy resin (G) and the curing agent (H). Mass parts. When the blending amount of the solid lubricant (I) is less than 1 part by mass, the lubricating effect is poor. On the other hand, when the blending amount exceeds 80 parts by mass, the paintability is lowered, which is not preferable.

The upper layer film (coating composition (Y) for film formation) is preferably further blended with one or more rust preventive additives (J) selected from the following (a) to (e).
(A) Phosphate (b) Ca ion exchange silica (c) Molybdate (d) Silicon oxide (e) One or more selected from triazoles, thiols, thiadiazoles, thiazoles, thiurams Organic compounds

The phosphate which is the said component (a) contains all kinds of salts, such as a single salt and a double salt. Moreover, there is no restriction | limiting in particular in the metal cation which comprises it, Any metal cations, such as zinc phosphate, magnesium phosphate, calcium phosphate, and aluminum phosphate, may be sufficient. Further, there is no limitation on the skeleton or the degree of condensation of phosphate ions, and any of normal salt, dihydrogen salt, monohydrogen salt or phosphite may be used. In addition, orthophosphate may be polyphosphate other than orthophosphate. Includes all condensed phosphates such as salts.
Moreover, corrosion resistance can further be improved by adding a calcium compound together with the phosphate which is the said component (a). The calcium compound may be any of calcium oxide, calcium hydroxide, and calcium salt, and one or more of these can be used. In addition, there are no particular restrictions on the type of calcium salt. In addition to simple salts containing only calcium as a cation such as calcium silicate, calcium carbonate, and calcium phosphate, calcium and calcium such as calcium phosphate / zinc, calcium phosphate / magnesium, etc. Double salts containing other cations may be used.

Moreover, the Ca ion exchange silica which is said component (b) is what fixed the calcium ion on the surface of the porous silica gel powder, Ca ion is discharge | released in a corrosive environment, and forms a precipitation film | membrane.
Any Ca ion-exchanged silica can be used, but those having an average particle size of 6 μm or less, preferably 4 μm or less are preferable, and for example, those having an average particle size of 2 to 4 μm can be used. When the average particle size of the Ca ion exchange silica exceeds 6 μm, the corrosion resistance is lowered and the dispersion stability in the coating composition is lowered.
The Ca concentration in the Ca ion exchange silica is preferably 1 mass% or more, and preferably 2 to 8 mass%. If the Ca concentration is less than 1 mass%, the rust prevention effect due to Ca release cannot be sufficiently obtained. The surface area, pH, and oil absorption amount of the Ca ion exchange silica are not particularly limited.

Examples of the Ca ion exchange silica as described above include WR Grace & Co. SHIELDEX C303 (average particle size 2.5 to 3.5 μm, Ca concentration 3 mass%), SHIELDEX AC3 (average particle size 2.3 to 3.1 μm, Ca concentration 6 mass%), SHIELDEX AC5 (average particle size 3. 8 to 5.2 μm, Ca concentration 6 mass% (all are trade names), SHIELDEX (average particle diameter 3 μm, Ca concentration 6 to 8 mass%) manufactured by Fuji Silysia Chemical Ltd., SHIELDEX SY710 (average particle diameter 2) 0.2 to 2.5 μm, Ca concentration of 6.6 to 7.5 mass%) (all are trade names) and the like can be used.
The molybdate that is the component (c) is not limited in its skeleton and degree of condensation, and examples thereof include orthomolybdate, paramolybdate, and metamolybdate. Moreover, all salts, such as a single salt and a double salt, are included, and a phosphomolybdate etc. are mentioned as a double salt.

  The silicon oxide as the component (d) may be either colloidal silica or dry silica. When colloidal silica is based on a water-based film-forming resin, for example, Snowtex O, Snowtex N, Snowtex 20, Snowtex 30, Snowtex 40, Snowtex C manufactured by Nissan Chemical Industries, Ltd. , Snowtex S (all are trade names), Cataloid S, Cataloid SI-350, Catalloid SI-40, Cataloid SA, Cataloid SN (all are trade names) manufactured by Catalytic Chemical Industries, Ltd. ) Adelite AT-20 to 50, Adelite AT-20N, Adelite AT-300, Adelite AT-300S, Adelite AT20Q (all are trade names) manufactured by ADEKA, etc. can be used.

In addition, when the solvent-based film forming resin is used as a base, for example, organosilica sol MA-ST-M, organosilica sol IPA-ST, organosilica sol EG-ST, organosilica sol E-ST manufactured by Nissan Chemical Industries, Ltd. -ZL, organosilica sol NPC-ST, organosilica sol DMAC-ST, organosilica sol DMAC-ST-ZL, organosilica sol XBA-ST, organosilica sol MIBK-ST (all are trade names), manufactured by Catalyst Kasei Kogyo Co., Ltd. OSCAL-1132, OSCAL-1232, OSCAL-1332, OSCAL-1432, OSCAL-1532, OSCAL-1632, OSCAL-1722 (all of which are trade names) can be used.
In particular, the organic solvent-dispersed silica sol is excellent in dispersibility and superior in corrosion resistance than fumed silica.

Examples of the fumed silica include AEROSIL R971, AEROSIL R812, AEROSIL R811, AEROSIL R974, AEROSIL R202, AEROSIL R805, AEROSIL 130, AEROSIL 200, AEROSIL 300, and more from AEROSIL 300CF manufactured by Nippon Aerosil Co., Ltd. Can also be used.
The fine-particle silica contributes to the formation of a dense and stable zinc corrosion product in a corrosive environment, and the corrosion product is considered to be able to suppress the promotion of corrosion by being densely formed on the plating surface. It has been.
From the viewpoint of corrosion resistance, it is preferable to use fine silica particles having a particle diameter of 5 to 50 nm, desirably 5 to 20 nm, more preferably 5 to 15 nm.

  Among the organic compounds of the component (e), triazoles include 1,2,4-triazole, 3-amino-1,2,4-triazole, 3-mercapto-1,2,4-triazole, 5- Amino-3-mercapto-1,2,4-triazole, 1H-benzotriazole, etc., and thiols include 1,3,5-triazine-2,4,6-trithiol, 2-mercaptobenzimidazole, etc. The thiadiazoles include 5-amino-2-mercapto-1,3,4-thiadiazole, 2,5-dimercapto-1,3,4-thiadiazole, and the thiazoles include 2-N, N -Diethylthiobenzothiazole, 2-mercaptobenzothiazole, etc., and thiurams include tetraethylthiuramdisulfur Such as soil, and the like, respectively.

  The compounding amount of the antirust additive component (J) (the total compounding amount of one or more self-repairing substances selected from the above components (a) to (e)) is the epoxy resin (G) and the curing agent. It is appropriate that the total solid content of (H) is 1 to 100 parts by mass, preferably 5 to 80 parts by mass, and more preferably 10 to 50 parts by mass. If the compounding amount of the anticorrosive additive component (J) is less than 1 part by mass, the effect of improving the corrosion resistance is small. On the other hand, if the compounding amount exceeds 100 parts by mass, the corrosion resistance decreases, which is not preferable.

  Further, in the upper layer film (coating composition (Y) for film formation), in addition to the above-mentioned antirust additive component, other oxide fine particles (for example, aluminum oxide, zirconium oxide, titanium oxide) as a corrosion inhibitor. , Cerium oxide, antimony oxide, etc.), phosphomolybdate (eg, aluminum phosphomolybdate), organic phosphoric acid and its salts (eg, phytic acid, phytate, phosphonic acid, phosphonate, and their metals) 1 type, or 2 or more types, such as a salt, an alkali metal salt, an alkaline-earth metal salt, etc.), an organic inhibitor (For example, a hydrazine derivative, a thiol compound, a dithiocarbamate etc.) can be added.

In the upper layer film (coating composition (Y) for film formation), if necessary, an organic coloring pigment (for example, a condensed polycyclic organic pigment, a phthalocyanine organic pigment, etc.), a coloring dye may be used as an additive. (Eg, organic solvent-soluble azo dyes, water-soluble azo metal dyes, etc.), inorganic pigments (eg, titanium oxide), chelating agents (eg, thiols), conductive pigments (eg, zinc, aluminum, nickel, etc.) Metal powder, iron phosphide, antimony-doped tin oxide, etc.), coupling agents (for example, silane coupling agents, titanium coupling agents, etc.), melamine / cyanuric acid adducts, etc. can do.
The thickness of the upper layer film is 0.1 to 5 μm, preferably 0.2 to 2 μm. If the film thickness is less than 0.1 μm, sufficient corrosion resistance cannot be obtained, while if it exceeds 5 μm, the conductivity is lowered.

In order to manufacture the surface-treated steel sheet as described above, after applying the surface treatment composition (X) (treatment liquid) containing the above-described components to the surface of the zinc-based plated steel sheet or the aluminum-based plated steel sheet Then, it is dried without being washed with water, and then a coating composition (Y) for forming an upper layer film containing the above components is applied and dried.
As a method of coating the surface treatment composition (X) on the surface of the plated steel plate, any method such as a coating method, a dipping method, a spray method, or the like can be adopted. As a coating method, any method such as a roll coater (3-roll method, 2-roll method, etc.), a squeeze coater, or a die coater may be used. In addition, after the coating process, dipping process or spraying process using a squeeze coater or the like, the coating amount can be adjusted, the appearance can be made uniform, and the film thickness can be made uniform by an air knife method or a roll drawing method.

  After coating the surface treatment composition (X), heat drying is performed without washing with water. For the heat drying treatment, a dryer, a hot air furnace, a high-frequency induction heating furnace, an infrared furnace, or the like can be used. The heat drying is desirably performed in the range of 30 to 200 ° C., preferably 40 ° C. to 140 ° C., at the ultimate plate temperature. If the heating and drying temperature is less than 30 ° C., a large amount of moisture remains in the film, resulting in insufficient corrosion resistance. In addition, when the heating and drying temperature exceeds 200 ° C., not only is it uneconomical, but there is a possibility that defects occur in the film and the corrosion resistance decreases.

  As a method for coating the coating composition (Y) for forming the upper layer film, any method such as a coating method, a dipping method, or a spray method can be employed. As a coating method, any method such as a roll coater (3-roll method, 2-roll method, etc.), a squeeze coater, or a die coater may be used. In addition, after the coating process, dipping process or spraying process using a squeeze coater or the like, the coating amount can be adjusted, the appearance can be made uniform, and the film thickness can be made uniform by an air knife method or a roll drawing method.

  After application of the coating composition (Y), heating drying is usually performed without washing with water, but a washing process may be performed after application of the coating composition. For the heat drying treatment, a dryer, a hot air furnace, a high frequency induction heating furnace, an infrared furnace, or the like can be used, but a high frequency induction heating furnace is particularly preferable from the viewpoint of corrosion resistance. The heat treatment is desirably performed in the range of 50 to 350 ° C., preferably 80 to 250 ° C., at the ultimate plate temperature. If the heating temperature is less than 50 ° C., a large amount of the solvent remains in the film, resulting in insufficient corrosion resistance. Further, when the heating temperature exceeds 350 ° C., not only is it uneconomical, but there is a possibility that defects occur in the film and the corrosion resistance is lowered.

The present invention includes a steel plate having a coating as described above on both sides or one side. Accordingly, examples of the form of the steel sheet of the present invention include the following.
(1) One side: plating film-surface treatment film-upper layer film, one side: plating film (2) One side: plating film-surface treatment film-upper layer film, one side: plating film-known phosphate treatment film, etc. (3) Both sides: plating film-surface treatment film-upper layer film (4) Single side: plating film-surface treatment film-upper layer film, one side: plating film-surface treatment film (film corresponding to the surface treatment film of the present invention)
(5) One side: plating film-surface treatment film-upper layer film, one side: plating film-organic film (film corresponding to the upper layer film of the present invention)

[Surface treatment composition for first layer (surface treatment film)]
Titanium-containing aqueous liquids A1 to A7, organophosphate compounds B1 to B6, vanadic acid compounds C1 to C3, zirconium fluoride compounds D1 to D3, zirconium carbonate compounds E1 to E3, water-soluble or water-dispersed used in the surface treatment composition The organic resins F1 to F7 are shown below. These components were blended in the proportions shown in Tables 1 and 2 to obtain surface treatment compositions P1 to P50.

(1) Production and production example 1 of titanium-containing aqueous liquids A1 to A7
Ammonia water (1: 9) was added dropwise to a solution in which 5 cc of a titanium tetrachloride 60% solution was made 500 cc with distilled water to precipitate titanium hydroxide. After washing with distilled water, 10 cc of a 30% hydrogen peroxide solution was added and stirred to obtain a yellow translucent viscous titanium-containing aqueous liquid A1 containing titanium.
・ Production example 2
A mixture of 10 parts by mass of tetraiso-propoxytitanium and 10 parts by mass of iso-propanol was dropped into a mixture of 10 parts by mass of 30% hydrogen peroxide and 100 parts by mass of deionized water with stirring at 20 ° C. over 1 hour. . Thereafter, the mixture was aged at 25 ° C. for 2 hours to obtain a yellow transparent, slightly viscous titanium-containing aqueous liquid A2.

・ Production Example 3
A titanium-containing aqueous liquid A3 was obtained under the same production conditions as in Production Example 2 except that tetra-n-butoxytitanium was used instead of tetraiso-propoxytitanium used in Production Example 2.
・ Production Example 4
A titanium-containing aqueous liquid A4 was obtained under the same production conditions as in Production Example 2 except that a tetramer of tetraiso-propoxytitanium was used instead of tetraiso-propoxytitanium used in Production Example 2.
・ Production Example 5
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. A5 was obtained.

・ Production Example 6
The titanium-containing aqueous liquid A3 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 A6.
・ Production Example 7
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% hydrogen peroxide solution 10 The mixture was added dropwise to a mixture of parts by mass and 100 parts by mass of deionized water at 10 ° C. with stirring for 1 hour. Thereafter, the mixture was aged at 10 ° C. for 24 hours to obtain a yellow transparent slightly viscous titanium-containing aqueous liquid A7.

(2) Organophosphate compounds B1 to B6
B1: 1-hydroxymethane-1,1-diphosphonic acid B2: 1-hydroxyethane-1,1-diphosphonic acid B3: 1-hydroxypropane-1,1-diphosphonic acid B4: 2-hydroxyphosphonoacetic acid B5: 3 -Phosphonobutane-1,2,4-tricarboxylic acid B6: Potassium 2-hydroxyphosphonoacetate (3) Vanadic acid compounds C1-C3
C1: ammonium metavanadate C2: sodium metavanadate C3: potassium metavanadate

(4) Zirconium fluoride compounds D1 to D3
D1: Zirconium ammonium fluoride D2: Zirconium sodium fluoride D3: Zirconium potassium fluoride (5) Zirconium carbonate compounds E1 to E3
E1: Ammonium zirconium carbonate E2: Sodium zirconium carbonate E3: Lithium zirconium carbonate

(6-1) Synthesis / Synthesis Example 1 of water-based organic resins F1 to F4
In a flask equipped with a nitrogen-filled tube, a ball condenser, a dropping funnel and a mechanical stirrer, 200 parts by mass of propylene glycol monomethyl ether was heated to 90 ° C., and then the temperature was maintained at 90 ° C., and styrene was added to the flask. A mixture of 10 parts by mass, 80 parts by mass of tert-butyl acrylate, 10 parts by mass of 2-hydroxyethyl acrylate, and 1 part by mass of azobisisobutyronitrile was added dropwise over 3 hours, and after completion of the addition, maintained at 90 ° C. for 2 hours. Then, it was cooled to room temperature to obtain an aqueous organic resin (acrylic resin solution) F1. The obtained acrylic resin has a Tg (glass transition point) of 33 ° C.
Synthesis example 2
In a flask equipped with a nitrogen-filled tube, a ball condenser, a dropping funnel and a mechanical stirrer, 200 parts by mass of propylene glycol monomethyl ether was heated to 90 ° C., and then the temperature was maintained at 90 ° C., and styrene was added to the flask. A mixture of 25 parts by mass, 60 parts by mass of methyl acrylate, 15 parts by mass of acrylamide and 1 part by mass of azobisisobutyronitrile was added dropwise over 3 hours. After completion of the addition, the mixture was further maintained at 90 ° C. for 2 hours and then cooled to room temperature. Thus, an aqueous organic resin (acrylic resin solution) F2 was obtained. The obtained acrylic resin has a Tg of 46 ° C.

Synthesis example 3
In a flask equipped with a nitrogen-filled tube, a ball condenser, a dropping funnel and a mechanical stirrer, 200 parts by mass of propylene glycol monomethyl ether was heated to 90 ° C., and then the temperature was maintained at 90 ° C., and styrene was added to the flask. A mixture of 55 parts by mass, 5 parts by mass of n-butyl acrylate, 20 parts by mass of 2-hydroxyethyl methacrylate, 20 parts by mass of N-methylacrylamide and 1 part by mass of azobisisobutyronitrile was added dropwise over 3 hours, and the addition was completed. Thereafter, the mixture was further maintained at 90 ° C. for 2 hours, and then cooled to room temperature to obtain an aqueous organic resin (acrylic resin solution) F3. The obtained acrylic resin has a Tg of 78 ° C.
Synthesis example 4
In a flask equipped with a nitrogen-filled tube, a ball condenser, a dropping funnel and a mechanical stirrer, 200 parts by mass of propylene glycol monomethyl ether was heated to 90 ° C., and the temperature was maintained at 90 ° C. A mixture of 80 parts by weight of methacrylate, 10 parts by weight of n-butyl acrylate, 10 parts by weight of 2-hydroxyethyl acrylate, and 1 part by weight of azobisisobutyronitrile is dropped over 3 hours. After being held, it was cooled to room temperature to obtain an aqueous organic resin (acrylic resin solution) F4. The obtained acrylic resin has a Tg of 56 ° C.

(6-2) Water-based organic resins F5 to F7
F5: “Superflex E-2500” (trade name, manufactured by Daiichi Kogyo Seiyaku Co., Ltd., water-based polyurethane resin)
F6: “Vaironal MD-1100” (trade name, manufactured by Toyobo Co., Ltd., water-based polyester resin)
F7: “ADEKA RESIN EM-0718” (trade name, manufactured by ADEKA, water-based epoxy resin)

[Coating composition for second layer (upper layer film)]
Epoxy resin solutions G1 to G9, curing agents H1 to H4, curing catalysts K1 to K4, rust preventive additives J1 to J6, and solid lubricants I1 to I3 used in the coating composition are shown below. Epoxy resin solutions G1 to G9 shown in Table 3 (those satisfying the conditions of the present invention are “epoxy resins (G)” used in the present invention) are appropriately combined with curing agents H1 to H4 and curing catalysts K1 to K4. Blended and obtained resin compositions S1 to S21 shown in Table 4 (those satisfying the conditions of the present invention are “epoxy resin (G) + curing agent (H)” used in the present invention). Rust preventive additives J1 to J6 and solid lubricants I1 to I3 are appropriately blended with the resin compositions S1 to S21, and the mixture is stirred for a predetermined time using a paint disperser (sand grinder). Things Q1-Q45 were obtained.

(1) Synthesis / Synthesis Example 5 of Epoxy Resin Solutions G1 to G9 (Equivalent to Invention Example)
In a reactor equipped with a thermometer, a stirrer and a heating device, 1448 parts by weight of epoxy resin “jER1007” (trade name, manufactured by Japan Epoxy Resin Co., Ltd., epoxy equivalent of about 2250, number average molecular weight of about 2900) and 507 parts by weight of cyclohexanone were added. The mixture was heated to 140 ° C. and completely dissolved in 2 hours. Next, ε-caprolactone “PLACCEL
M ”(trade name, manufactured by Daicel) 73 parts by mass and 0.08 part by mass of dibutyltin oxide were added (solid content 75% during reaction), and the temperature was raised to 170 ° C. and reacted for 4 hours. Thereafter, 395 parts by mass of methyl isobutyl ketone, 371 parts by mass of cyclohexanone, and 585 parts by mass of an aromatic hydrocarbon solvent “Swazole 1500” (trade name, manufactured by Maruzen Petrochemical Co., Ltd.) were added, and an epoxy resin solution having a solid content of 35% G1 was obtained. The molar ratio of epoxy resin / ε-caprolactone in this epoxy resin solution G1 is shown in Table 3.

Synthesis example 6 (equivalent to invention example)
In a reactor equipped with a thermometer, a stirrer and a heating device, 1448 parts by weight of epoxy resin “jER1007” (trade name, manufactured by Japan Epoxy Resin Co., Ltd., epoxy equivalent of about 2250, number average molecular weight of about 2900) and 507 parts by weight of cyclohexanone were added. The mixture was heated to 140 ° C. and completely dissolved in 2 hours. Next, ε-caprolactone “PLACCEL
M ”(trade name, manufactured by Daicel) 73 parts by mass and 0.08 part by mass of dibutyltin oxide were added (solid content 75% during reaction), and the temperature was raised to 170 ° C. and reacted for 4 hours. This was cooled to 80 ° C., and 44 parts by mass of methyl isobutyl ketone, 1024 parts by mass of butyl cellosolve and 54 parts by mass of 3-amino-1,2,4-triazole were added (solid content during reaction was 50%), and the epoxy group disappeared. The reaction was continued for about 6 hours. Thereafter, 395 parts of methyl isobutyl ketone, 371 parts by weight of cyclohexanone, 585 parts by weight of an aromatic hydrocarbon solvent “Swazole 1500” (trade name, manufactured by Maruzen Petrochemical Co., Ltd.) are added, and an epoxy resin solution G2 having a solid content of 35% is added. Got. Table 3 shows the molar ratio of epoxy resin / ε-caprolactone / 3-amino-1,2,4-triazole of this epoxy resin solution G2.

Synthesis examples 7 to 10 (equivalent to invention examples)
Epoxy resin solutions G3 to G6 were produced in the same manner as in Synthesis Example 5 by adjusting the amount of solvent so that the solid content was as shown in Table 3 and the solid content during the reaction was the same. As the epoxy resin, “jER1007” (trade name, manufactured by Japan Epoxy Resin, epoxy equivalent of about 2250, number average molecular weight of about 2900) is used in Synthesis Examples 7, 8, and 10, and “jER1009” (product is manufactured in Synthesis Example 9). Name, manufactured by Japan Epoxy Resin, epoxy equivalent of about 3000, number average molecular weight of about 3750). Table 3 shows the molar ratio of epoxy resin / ε-caprolactone / 3-amino-1,2,4-triazole of the epoxy resin solutions G3 to G6.

Synthesis example 11 (equivalent to comparative example)
In a reactor equipped with a thermometer, a stirrer, and a heating device, 1518 parts by mass of epoxy resin “jER1007” (trade name, manufactured by Japan Epoxy Resin Co., Ltd., epoxy equivalent of about 2250, number average molecular weight of about 2900) and 878 parts by mass of cyclohexanone were added. The mixture was heated to 140 ° C. and completely dissolved in 2 hours. This was cooled to 80 ° C., 411 parts by mass of methyl isobutyl ketone and 57 parts by mass of 3-amino-1,2,4-triazole were added, and the reaction was continued for about 6 hours until the epoxy group disappeared. Thereafter, 28 parts by mass of methyl isobutyl ketone, 1023 parts by mass of butyl cellosolve, 585 parts by mass of an aromatic hydrocarbon solvent “Swazole 1500” (trade name, manufactured by Maruzen Petrochemical Co., Ltd.) are added, and an epoxy resin solution having a solid content of 35% G7 was obtained. Table 3 shows the molar ratio of epoxy resin / 3-amino-1,2,4-triazole of this epoxy resin solution G7.

Synthesis example 12 (equivalent to comparative example)
The amount of the solid as shown in Table 3 was adjusted, and the amount of the solvent was adjusted so that the solid content during the reaction was the same, and an epoxy resin solution G8 was produced in the same manner as in Synthesis Example 11. As the epoxy resin, “jER1009” (trade name, manufactured by Japan Epoxy Resin Co., Ltd., epoxy equivalent of about 3000, number average molecular weight of about 3750) was used. Table 3 shows the molar ratio of epoxy resin / 3-amino-1,2,4-triazole in the epoxy resin solution G8.

(2) Curing agents H1 to H4 (H1 to H3 are isocyanate compounds)
H1: “Takenate B-870N” (trade name, manufactured by Mitsui Chemicals Polyurethanes, Inc., IPDI MEK oxime block)
H2: “Sumijour BL3175” (trade name, manufactured by Sumika Bayer Urethane Co., Ltd., isocinurate type block isocyanate)
H3: “Duranate MF-B80M” (trade name, manufactured by Asahi Kasei Chemicals Corporation, HMDI MEK oxime block)
H4: “Cymel 325” (trade name, manufactured by Nippon Cytec Industries, Inc., imino group type melamine resin)
(3) Curing catalysts K1 to K4
K1: dibutyltin dilaurate K2: cobalt naphthenate K3: stannous chloride K4: N-ethylmorpholine

(4) Rust preventive additives J1-J6
J1: Calcium ion exchange silica J2: Colloidal silica J3: Fumed silica J4: Aluminum dihydrogen triphosphate J5: Aluminum phosphomolybdate J6: Tetraethylthiuram disulfide (5) Solid lubricants I1-I3
I1: “LUVAX1151” (trade name, manufactured by Nippon Seiwa Co., Ltd., polyethylene wax)
I2: “Seridust 3620” (trade name, manufactured by Clariant Japan Co., Ltd., polyethylene wax)
I3: “MP1100” (trade name, manufactured by Mitsui DuPont Fluorochemical Co., Ltd., tetrafluoroethylene fine particles)

[Manufacture of surface-treated steel sheets]
Using the various plated steel sheets shown in Table 6 as the treatment original plate, the surface of the plated steel sheet was subjected to alkaline degreasing treatment, water washing and drying, then treated (coated) with a surface treatment composition for forming a lower layer film, and dried at various temperatures. . Subsequently, the coating composition for upper layer film formation was apply | coated to the upper part, and it was made to dry at various temperatures, and obtained the surface treatment steel plate of the example of this invention and the comparative example. In addition, the film thickness of the lower layer film and the upper layer film was adjusted by the solid content (heating residue) of the film composition, the processing time, and the like.
Tables 7 to 10 show the results of evaluating the quality performance (white rust resistance, white rust resistance after alkali degreasing, electrical conductivity, abrasion resistance) of the obtained surface-treated steel sheets together with the production conditions and the coating composition. . In addition, the measurement and evaluation method of each quality performance is as follows.

(1) White rust resistance About each sample, the salt spray test (JIS-Z-2371) was given and it evaluated by the white rust area rate after 500 hours. The evaluation criteria are as follows.
◎: White rust occurrence area ratio less than 5% ○: White rust occurrence area ratio 5% or more and less than 10% ○-: White rust occurrence area ratio 10% or more and less than 25% △: White rust occurrence area ratio 25% or more Less than 50% x: White rust generation area ratio 50% or more (2) White rust resistance after alkali degreasing For each sample, an alkaline treatment solution “CLN-364S” (60 ° C., spray 2) manufactured by Nippon Parker Rising Co., Ltd. Min), the above salt spray test was performed, and the white rust area ratio after 200 hours was evaluated. The evaluation criteria are as follows.
◎: White rust occurrence area ratio less than 5% ○: White rust occurrence area ratio 5% or more and less than 10% ○-: White rust occurrence area ratio 10% or more and less than 25% △: White rust occurrence area ratio 25% or more Less than 50% x: White rust generation area ratio 50% or more

(3) Conductivity The interlayer insulation resistance value was measured based on JIS-C-2550. The evaluation criteria are as follows.
○: 3Ω · cm less than ² / sheets △: 3~5Ω · cm ² / sheet ×: 5Ω · cm ² / sheet exceeded (4) with resistance to abrasion resistance rubbing tester (by Taihei Rika Kogyo Ltd. Co.), the After rubbing the sample with corrugated cardboard, the surface of the sample was visually observed and evaluated according to the following evaluation criteria. The test was performed at 400 g (surface pressure 9.8 kPa), sliding distance 60 mm, speed 120 mm / s, and number of rubbing times 1000 times.
◎: The number of wrinkles is 0 ○: The number of wrinkles is 1 to 2 Δ: The number of wrinkles is 3 to 10 ×: The number of wrinkles is 11 or more or discolored (number cannot be measured)

  According to Tables 7 to 10, the examples of the present invention are excellent in white rust resistance and white rust resistance (corrosion resistance) after alkali degreasing, conductivity, and abrasion resistance. On the other hand, in the comparative example, one or more of white rust resistance and white rust resistance (corrosion resistance) after alkali degreasing, conductivity and abrasion resistance are inferior to those of the present invention.

In Tables 1 and 2, * 1 to * 7 indicate the following contents.
* 1 Titanium-containing aqueous liquids A1 to A7 described in the main text of the specification
* 2 Organophosphate compounds B1 to B6 described in the specification text
* 3 Vanadic acid compounds C1 to C3 described in the specification text
* 4 Zirconium fluoride compounds D1 to D3 described in the specification text
* 5 Zirconium carbonate compounds E1 to E3 described in the specification text
* 6 Water-soluble or water-dispersible organic resins F1 to F7 described in the main text of the specification
* 7 Mass parts of solid content

In Tables 7 to 10, * 1 to * 3 indicate the following contents.
* 1 Plated steel sheets T1 to T9 listed in Table 6
* 2 Surface treatment compositions P1 to P50 described in Tables 1 and 2
* 3 Coating compositions Q1 to Q45 described in Table 5

Claims (4)

At least one titanium selected from a hydrolyzable titanium compound, a hydrolyzable titanium compound low condensate, titanium hydroxide, and a titanium hydroxide low condensate on the surface of a zinc-based plated steel sheet or an aluminum-based plated steel sheet With respect to 100 parts by mass of the solid content of the titanium-containing aqueous liquid (A) obtained by mixing the compound with hydrogen peroxide, 1-hydroxymethane-1,1-diphosphonic acid, 1-hydroxyethane-1,1- One or more selected from diphosphonic acid, 1-hydroxypropane-1,1-diphosphonic acid, 2-hydroxyphosphonoacetic acid, 2-phosphonobutane-1,2,4-tricarboxylic acid, and salts thereof 1 to 400 parts by mass of the organic phosphate compound (B), vanadate, lithium orthovanadate, sodium orthovanadate, lithium metavanadate 1 to 400 parts by mass of one or more vanadic acid compounds (C) selected from potassium metavanadate, sodium metavanadate, ammonium metavanadate, sodium pyrovanadate, vanadyl chloride and vanadyl sulfate, zirconium fluoride 1 to 400 parts by mass of one or more zirconium fluoride compounds (D) selected from sodium, potassium, lithium, and ammonium salts of hydrogen acid, sodium carbonate, potassium salt, and lithium of zirconium carbonate Film thickness formed by applying and drying a surface treatment composition (X) containing 1 to 400 parts by mass of one or more zirconium carbonate compounds (E) selected from salts and ammonium salts Has a surface treatment film of 0.01 to 1.0 μm, and an epoxy resin (g 1) and a cyclic ester compound (g2) represented by the following formula (2): [number of moles of epoxy resin (g1)] / [number of moles of cyclic ester compound (g2)] = 0.05 to 0.5 An epoxy resin (G) having a primary hydroxyl group in the resin, obtained by reacting under conditions ,

(In the formula, R = H or CH ₃ , n is 3 to 6)
It contains a curing agent (H) having a group that crosslinks with a hydroxyl group and a solid lubricant (I), and the solid content mass ratio (G) / (H) of the epoxy resin (G) and the curing agent (H) is 95 / 5 to 55/45, the content of the solid lubricant (I) is 1 to 80 parts by mass with respect to the total solids of 100 parts by mass of the epoxy resin (G) and the curing agent (H). A surface-treated steel sheet excellent in corrosion resistance, electrical conductivity and abrasion resistance, characterized in that it has an upper film with a thickness of 0.1 to 5 μm formed by applying and drying the coating composition (Y).   The surface treatment composition (X) further contains a water-soluble organic resin and / or a water-dispersible organic resin (F) of 2000 parts by mass or less based on 100 parts by mass of the solid content of the titanium-containing aqueous liquid (A). The surface-treated steel sheet excellent in corrosion resistance, conductivity and abrasion resistance according to claim 1.   The epoxy resin (G) is an epoxy resin in which an epoxy group is modified with an active hydrogen-containing compound, and a part or all of the active hydrogen-containing compound is a hydrazine derivative having active hydrogen. A surface-treated steel sheet having excellent corrosion resistance, electrical conductivity and abrasion resistance according to 1 or 2. The coating composition (Y) further contains at least one rust preventive additive (J) selected from the following (a) to (e), and the solid content of the epoxy resin (G) and the curing agent (H). The surface-treated steel sheet excellent in corrosion resistance, conductivity and abrasion resistance according to any one of claims 1 to 3, wherein the solid content is 1 to 100 parts by mass with respect to 100 parts by mass in total. .
(A) Phosphate (b) Ca ion exchange silica (c) Molybdate (d) Silicon oxide (e) One or more selected from triazoles, thiols, thiadiazoles, thiazoles, thiurams Organic compounds