JP3381647B2 - Organic coated steel sheet with excellent corrosion resistance - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic coated steel sheet which is most suitable for automobiles, home appliances, building materials, etc. To adapt to environmental issues such as volatilization and elution of harmful substances from products, excellent corrosion resistance can be obtained without applying a chromate film to the underlying chemical conversion treatment film. The present invention relates to an environment-adaptive surface-treated steel sheet which, when applied, provides not only corrosion resistance but also excellent chromium elution resistance.

[0002]

2. Description of the Related Art For the purpose of improving corrosion resistance (white rust resistance, red rust resistance) on the surface of a zinc-based plated steel sheet or an aluminum-based plated steel sheet for steel sheets for home appliances, steel sheets for building materials, steel sheets for automobiles, etc. Steel sheets that have been subjected to a chromate treatment with a treatment liquid containing chromic acid, dichromic acid or a salt thereof as a main component are widely used. This chromate treatment is an economical treatment method that has excellent corrosion resistance and can be performed relatively easily. The anticorrosion mechanism of the chromate film is 3
It is considered that this is due to the barrier effect of hydrated oxide of hexavalent chromium and the self-repairing action of hexavalent chromium.

Chromate treatment methods include reaction type, electrolytic type, and coating type. Among them, the coating-type chromate treatment has recently been performed because the excellent corrosion resistance can be obtained by controlling the ratio of hexavalent chromium to trivalent chromium in the treatment liquid or adding silica. The amount used as is also increasing rapidly. Further, in the case of reactive or electrolytic chromate treatment, in order to supplement the corrosion resistance of the chromate film, a sealing treatment may be performed immediately after the chromate treatment with a treatment liquid containing hexavalent chromium.

However, since hexavalent chromium is a pollution control substance, it is necessary to suppress the elution of hexavalent chromium from the chromate film. For example, in the case of alkali degreasing the rust preventive oil and the press oil adhered during the press working of the coating type chromate treated steel sheet, it is necessary to suppress the elution of hexavalent chromium into the alkali degreasing liquid. Further, the same consideration is required in the chromium sealing treatment performed on the surface of the reactive chromate-treated steel sheet or the electrolytic chromate-treated steel sheet for the purpose of improving the corrosion resistance. Therefore, there is an increasing need for chromate treatment in which hexavalent chromium is not eluted from the chromate film.

For these reasons, various studies have been conducted to suppress the elution of chromium during alkali degreasing of the coating type chromate-treated film and to improve the corrosion resistance. As one of the methods, trivalent chromium in the chromate treatment liquid /
Although a method of increasing the reduction rate of hexavalent chromium is known, increasing the reduction rate in the treatment liquid lowers the corrosion resistance, and thus there is a limit to the increase in the reduction rate. In addition to this method, the following method is disclosed.

(A) The drying temperature of the chromate treatment is set to a plate temperature of 150 to 250 ° C., and after coating the resin, the temperature is set to 150 again.
Method of drying at ˜250 ° C. (JP-A-4-28878) (B) Method of suppressing elution of chromium ions by adding a reducing agent to the upper aqueous resin film (JP-A-7-1)
No. 80069) (C) A method of suppressing the elution of chromium ions by adding polyethyleneoxyol to the upper epoxy ester resin film (Japanese Patent Laid-Open No. 7-243055).

On the other hand, from the viewpoint that the chromate treatment itself may adversely affect the human body and the environment, many pollution-free treatment techniques have been proposed which do not depend on the chromate treatment. Among them, some methods using organic compounds and organic resins have been proposed, and the following methods can be mentioned, for example.

(1) Method using tannic acid (for example,
(JP-A-51-71233) (2) A method using a thermosetting coating material in which an epoxy resin, an amino resin and tannic acid are mixed (for example, JP-A-63-9).
(0581) (3) A method using a mixed composition of an aqueous resin and a polyhydric phenolcarboxylic acid (for example, JP-A-8-325760).
How to utilize the chelating power of tannic acid such as

(4) A surface treatment method in which an aqueous solution of a hydrazine derivative is applied to the surface of a tin plate or a zinc iron plate (for example,
Japanese Patent Publication No. 53-27694, Japanese Patent Publication No. 56-10386
(5) A method of using a rust preventive agent containing an amine addition salt obtained by adding an amine to a mixture of acyl sarcosine and benzotriazole (for example, JP-A-58-130284).
(6) A method using a treating agent in which a heterocyclic compound such as a benzothiazole compound and tannic acid are mixed (for example, JP-A-57-198267).

[0010]

However, the above-mentioned prior arts (a) to (c) aimed at suppressing chromium elution include:
There are the following problems. First, the method of (a) above
Since some hexavalent chromium ions permeate the upper organic resin film, there is a limit to the suppression of chromium elution. Also,
The method (b) above aims at reducing hexavalent chromium in the chromate film to trivalent chromium.
Not only is there a limit to the suppression of chromium elution, but there is also the problem of reduced corrosion resistance. Further, the method (c) is expected to complex hexavalent chromium with polyethyleneoxyol, but has a problem that the corrosion resistance is lowered as in the method (b).

Further, the prior arts (1) to (6) which do not use the chromate treatment also have the following problems. First, all of the above methods (1) to (4) have problems in terms of corrosion resistance and the like. That is, the method (1) has insufficient corrosion resistance, and a uniform appearance after treatment cannot be obtained. In addition, the method (2) above is applied directly to a zinc-based or aluminum-based plating surface in a thin film form (0.1 to 5).
It is not intended to form a rust-preventive film of μm), and therefore, even if it is applied in a thin film on the surface of zinc-based or aluminum-based plating, a sufficient anticorrosion effect cannot be obtained. Similarly, the method (3) also has insufficient corrosion resistance.

Furthermore, the above method (4) is not applied to a zinc-based or aluminum-based plated steel sheet, and even if it is applied to a zinc-based or aluminum-based plated steel sheet, the obtained film has a network structure. It does not have sufficient barrier properties, and therefore has insufficient corrosion resistance. In addition, Japanese Examined Japanese Patent Publication No. 53-23772
JP-B-56-10386, a water-soluble polymer compound (polyvinyl alcohol, maleic acid ester copolymer, acrylic acid ester copolymer, etc.) is mixed with an aqueous solution of a hydrazine derivative in order to improve the uniformity of the film. However, sufficient corrosion resistance cannot be obtained with a simple mixture of an aqueous solution of a hydrazine derivative and a water-soluble polymer compound.

Further, the above methods (5) and (6) are not intended to form a rust preventive coating on the surface of a zinc-based or aluminum-based plated steel sheet in a short time.
Even if the treating agent is applied to the surface of the plated steel sheet, excellent corrosion resistance cannot be obtained because there is no barrier against corrosion factors such as oxygen and water. Regarding the method (6), mixing with a resin (epoxy resin, acrylic resin, urethane resin, nitrocellulose resin, vinyl chloride resin, etc.) as an additive is also described, but a complex such as a benzothiazole compound is mentioned. Sufficient corrosion resistance cannot be obtained with a simple mixture of a ring compound and a resin.

Further, in any of the above methods (1) to (6), in order to remove the oil applied to the surface by press working, etc., the alkaline degreasing of about pH 9 to 11 by spraying is carried out under practical conditions. In the above, there is a problem that the film is peeled off or damaged by alkali degreasing, and the corrosion resistance cannot be maintained. Therefore, these methods are not suitable for practical use as a method for forming a rust preventive film.

Therefore, the object of the present invention is to solve the problems of the prior art and to obtain excellent corrosion resistance without applying a chromate film to the underlying chemical conversion coating, and to obtain a chromate on the chemical conversion coating. An object of the present invention is to provide an organic coated steel sheet which, when a coating is applied, can obtain not only corrosion resistance but also excellent chromium elution resistance.

[0016]

Means for Solving the Problems As a result of intensive investigations by the present inventors in order to solve the above-mentioned problems, the upper layer of a chemical conversion coating formed on the surface of a zinc-based plated steel sheet or an aluminum-based plated steel sheet, Along with forming a specific chelate-forming resin film, by adding an appropriate amount of a specific rust-preventive additive in this chelate-forming resin film, excellent corrosion resistance can be obtained without using chromate treatment as a chemical conversion treatment, and It was found that when chromate treatment is used as the chemical conversion treatment, it is possible to obtain significantly better corrosion resistance than conventional chromate treated steel sheets, and also to obtain excellent chromium elution resistance due to the specific chelate-forming resin film. It was

[0017]

The present invention has been made on the basis of such knowledge, and its characteristic constitution is as follows. [1] A hydrazine derivative (C) having a chemical conversion treatment film on the surface of a zinc-based plated steel sheet or an aluminum-based plated steel sheet, and a film-forming organic resin (A) and a part or all of the compounds having active hydrogen on the upper part thereof. A reaction product with an active hydrogen-containing compound (B), and zinc phosphate and / or aluminum phosphate (a), wherein the content of the zinc phosphate and / or aluminum phosphate (a) is the above. An organic coated steel sheet having excellent corrosion resistance, characterized by having an organic coating having a film thickness of 0.1 to 5 μm, which is 1 to 100 parts by weight (solid content) with respect to 100 parts by weight of reaction product (solid content). .

[2] A hydrazine derivative having a chemical conversion treatment film on the surface of a zinc-based plated steel sheet or an aluminum-based plated steel sheet, and a film-forming organic resin (A) and a part or all of the compounds have active hydrogen on the upper part thereof. (C) containing a reaction product with an active hydrogen-containing compound (B), zinc phosphate and / or aluminum phosphate (a), and a calcium compound (b), wherein the zinc phosphate and / or phosphorus The total content of the aluminum oxide (a) and the calcium compound (b) is 1 to 100 parts by weight (solid content) with respect to 100 parts by weight (solid content) of the reaction product, and zinc phosphate and / or Alternatively, the weight ratio (a) / (b) of the content (solid content) of aluminum phosphate (a) and calcium compound (b) is 1/99 to 99/1, and the film thickness is 0.1 to 5 μm. Organic peel Excellent organic coated steel sheet in corrosion resistance characterized by having a.

[3] A hydrazine derivative in which the surface of a zinc-based plated steel sheet or an aluminum-based plated steel sheet has a chemical conversion treatment film, and the film-forming organic resin (A) and a part or all of the compounds have active hydrogen on the upper part thereof. (C) a reaction product with an active hydrogen-containing compound (B), zinc phosphate and / or aluminum phosphate (a), and a solid lubricant (c), wherein the zinc phosphate and / or The content of aluminum phosphate (a) is 100 when the reaction product is
1 to 100 parts by weight (solid content) relative to parts by weight (solid content), and the content of the solid lubricant (c) is 1 to 80 parts by weight relative to 100 parts by weight (solid content) of the reaction product ( An organic coated steel sheet having excellent corrosion resistance, characterized in that it has an organic coating having a film thickness of 0.1 to 5 μm, which is a solid content).

[4] A hydrazine derivative having a chemical conversion treatment film on the surface of a zinc-based plated steel sheet or an aluminum-based plated steel sheet, and the film-forming organic resin (A) and a part or all of the compounds have active hydrogen on the upper part thereof. A reaction product of (C) with an active hydrogen-containing compound (B), zinc phosphate and / or aluminum phosphate (a), a calcium compound (b), and a solid lubricant (c), The total content of the zinc phosphate and / or aluminum phosphate (a) and the calcium compound (b) is 1 to 100 parts by weight (solid content) with respect to 100 parts by weight (solid content) of the reaction product. And the weight ratio (a) / (b) of the content (solid content) of zinc phosphate and / or aluminum phosphate (a) and calcium compound (b) is 1/99 to 99.
/ 1, the content of the solid lubricant (c) is 1 to 80 parts by weight (solid content) with respect to 100 parts by weight (solid content) of the reaction product, and the film thickness is 0.1 to 5 μm. An organic coated steel sheet having excellent corrosion resistance, which is characterized by having the organic coating of.

[5] In the organic coated steel sheet according to any one of the above [1] to [4], the film-forming organic resin (A) is an epoxy group-containing resin (D), which is excellent in corrosion resistance. Coated steel sheet. [6] In the organic coated steel sheet according to any one of the above [1] to [5],
An organic coated steel sheet having excellent corrosion resistance, wherein the hydrazine derivative (C) having active hydrogen is a pyrazole compound having active hydrogen and / or a triazole compound having active hydrogen.

[7] In the organic coated steel sheet according to any one of the above [1] to [6], a hydrazine derivative (C) having active hydrogen
Is contained in the active hydrogen-containing compound (B) in an amount of 10 to 100 mol%, which is an organic coated steel sheet having excellent corrosion resistance. [8] In the organic coated steel sheet according to any one of the above [5] to [7],
An organic coated steel sheet having excellent corrosion resistance, wherein the epoxy group-containing resin (D) is an epoxy resin represented by the following formula (1).

[Chemical 2]

The basic characteristics of the organic coated steel sheet of the present invention are:
A chemical conversion treatment film is formed on the surface of a zinc-based plated steel sheet or an aluminum-based plated steel sheet, and an activity consisting of a film-forming organic resin (A) and a hydrazine derivative (C) in which some or all of the compounds have active hydrogen is formed on the upper layer. By reacting with the hydrogen-containing compound (B), the hydrazine derivative (C) as a chelate-forming group is added to the film-forming resin (A).
And a chelate-forming resin which is a reaction product thereof is used as a base resin, zinc phosphate and / or aluminum phosphate (a) is added as an anticorrosive additive, and a calcium compound (b ) Is included in the formation of an organic film.

The anticorrosion mechanism by such an organic film composed of such a specific reaction product is not always clear, but the mechanism can be presumed as follows. That is, by adding a hydrazine derivative to the film-forming organic resin, not just a low-molecular weight chelating agent, (1) the dense organic polymer film has the effect of blocking corrosion factors such as oxygen and chlorine ions. (2) The hydrazine derivative can firmly bind to the surface of the first layer film to form a stable passivation layer, and (3) the free hydrazine derivative in the film traps zinc ions eluted by the corrosion reaction. However, since a stable insoluble chelate compound layer is formed, the formation of the ion conductive layer at the interface is suppressed and the progress of corrosion is suppressed. It is believed that excellent corrosion resistance can be obtained.

Further, when such an organic film is formed on the upper layer of the chromate film, the barrier effect of the organic film itself not only suppresses the elution of hexavalent chromium from the chromate film, but also the hydrazine in the organic resin. Since the derivative captures hexavalent chromium eluted from the chromate film, it is considered that excellent chromium elution resistance can be obtained.

As a result of the above, as a chemical conversion treatment film for the base, 6
Even when a chemical conversion coating containing no valent chromium (for example, a phosphate coating) is used, excellent corrosion resistance comparable to that of a chromate coating is obtained, and when a chromate coating is used as the chemical conversion coating, It is considered that, since it is combined with the anticorrosion effect by the organic film, it is significantly superior to the conventional chromate-treated steel sheet, but the corrosion resistance is obtained, and the excellent chromium elution resistance is obtained.

When an epoxy group-containing resin is used as the film-forming organic resin (A), a dense barrier film is formed by the reaction between the epoxy group-containing resin and the cross-linking agent, and this barrier film contains oxygen. Since it has an excellent ability to suppress the penetration of corrosion factors such as, and the hydroxyl group in the molecule provides an excellent binding force to the base material, particularly excellent corrosion resistance is obtained. Furthermore, a hydrazine derivative (C) having active hydrogen
In particular, by using a pyrazole compound having active hydrogen and / or a triazole compound having active hydrogen, more excellent corrosion resistance can be obtained.

As in the prior art, merely mixing the hydrazine derivative with the film-forming organic resin has almost no effect of improving the corrosion inhibition. The reason is that the hydrazine derivative which is not incorporated in the molecule of the film-forming organic resin forms a chelate compound with zinc eluted in a corrosive environment, but the chelate compound does not form a dense barrier layer because of its low molecular weight. It is thought to be because of this. On the other hand, by incorporating a hydrazine derivative into the molecule of the film-forming organic resin as in the present invention, a markedly excellent corrosion inhibiting effect can be obtained.

In addition, the organic coated steel sheet of the present invention is particularly excellent by blending an appropriate amount of zinc phosphate and / or aluminum phosphate (a) into the organic coating formed of the specific reaction product as described above. It is possible to obtain anticorrosion performance (self-healing action at the film defect portion). The anticorrosion mechanism obtained by blending zinc phosphate and / or aluminum phosphate (a) in this specific organic film is considered to proceed in the following reaction steps.

[First step]: In a corrosive environment,
Zinc and aluminum, which are plating metals, are eluted. [Second step]: Zinc phosphate and / or aluminum phosphate undergoes a hydrolysis reaction and dissociates into phosphate ions. [Third step]: The eluted zinc ions and aluminum ions undergo a complex formation reaction with phosphate ions to form a dense and sparingly soluble protective film, which seals the film defects.
Suppresses corrosion reaction.

Even if zinc phosphate and / or aluminum phosphate is added to a general organic film, a certain degree of anticorrosive effect can be obtained, but as in the present invention, phosphoric acid is contained in an organic film made of a specific chelate-modified resin. It is considered that by incorporating zinc and / or aluminum phosphate, the corrosion inhibiting effects of both are combined, and thereby an extremely excellent anticorrosion effect is exhibited.

Further, in the organic coated steel sheet of the present invention, zinc phosphate and / or aluminum phosphate (a) and calcium compound (b) are added in combination to the organic coating formed of the specific reaction product as described above. As a result, a further effect of improving corrosion resistance can be obtained. The reason for this is considered as follows. Since the self-repairing action of zinc phosphate and / or aluminum phosphate is triggered by the elution of the plating metal (first step) as described above, the corrosion reaction is suppressed at the very early stage of corrosion, but the corrosion reaction Cannot be completely suppressed. On the other hand, by using a calcium compound, which is a metal that is a base metal rather than zinc or aluminum, the preferential elution of calcium rather than the plating metal acts as the above-mentioned trigger, and thereby corrosion does not depend on the elution of the plating metal. The reaction can be suppressed. Due to such a mechanism, it is considered that a combined rust preventive effect can be obtained by using zinc phosphate and / or aluminum phosphate in combination with a calcium compound.

[0033]

BEST MODE FOR CARRYING OUT THE INVENTION The details of the present invention and the reasons for limitation thereof will be described below. Examples of the zinc-based plated steel sheet as the base of the organic coated steel sheet of the present invention include a galvanized steel sheet and Zn-Ni.
Alloy-plated steel sheet, Zn-Fe alloy-plated steel sheet (electroplated steel sheet and galvannealed steel sheet), Zn-Cr
Alloy-plated steel sheet, Zn-Mn alloy-plated steel sheet, Zn-C
o alloy plated steel sheet, Zn-Co-Cr alloy plated steel sheet,
Zn-Cr-Ni alloy plated steel sheet, Zn-Cr-Fe alloy plated steel sheet, Zn-Al alloy plated steel sheet (for example, Z
n-5% Al alloy plated steel plate, Zn-55% Al alloy plated steel plate), Zn-Mg alloy plated steel plate, Zn-Al-
It is possible to use Mg plated steel sheets, and further zinc-based composite plated steel sheets (for example, Zn—SiO ₂ dispersion plated steel sheets) in which metal oxides, polymers and the like are dispersed in the plating films of these plated steel sheets.

Further, it is also possible to use a multi-layer plated steel sheet obtained by plating two or more layers of the same kind or different kinds among the above-mentioned plating. Further, as the aluminum-based plated steel sheet which is the base of the organic coated steel sheet of the present invention, an aluminum-plated steel sheet, an Al-Si alloy-plated steel sheet, or the like can be used. Further, as the plated steel sheet, a steel sheet surface may be preliminarily plated with Ni or the like and then various kinds of plating as described above may be performed thereon. As the plating method, any of an electrolysis method (electrolysis in an aqueous solution or electrolysis in a non-aqueous solvent), a melting method and a vapor phase method can be adopted.

If necessary, in order to prevent film defects and unevenness from occurring when a two-layer film as described later is formed on the surface of the plating film, alkaline degreasing, solvent degreasing, or surface degreasing on the surface of the plating film may be performed in advance as necessary. A treatment such as a conditioning treatment (alkaline surface conditioning treatment, acidic surface conditioning treatment) can be performed in advance. In addition, in order to prevent blackening (a kind of oxidation phenomenon of the plating surface) under the use environment of the organic coated steel sheet, iron group metal ions (Ni
Surface conditioning treatment with an acidic or alkaline aqueous solution containing ions, Co ions, Fe ions) can be performed. When an electrogalvanized steel sheet is used as a base steel sheet, iron group metal ions (Ni ions, Co ions, Fe ions) are added to the electroplating bath for the purpose of preventing blackening.
It is possible to add 1 ppm or more of these metals in the plating film by adding. In this case, there is no particular upper limit on the iron group metal concentration in the plating film.

Next, the chemical conversion coating formed on the surface of the zinc-plated steel sheet or the aluminum-plated steel sheet will be described. This chemical conversion coating is formed for the purpose of suppressing the activity of the plated steel sheet and improving the corrosion resistance and the adhesion, and its type is not particularly limited, and the chemical conversion coating and the chromate coating containing no hexavalent chromium can be used. Either is fine.

Examples of the chemical conversion treatment film containing no hexavalent chromium include (1) a phosphate treatment film, (2) a molybdate or tungstate treatment film, a passivation film such as a phosphoric acid / molybdic acid treatment film, 3) Alkali silicate treatment film composed of alkali metal oxide such as lithium oxide and silicon oxide (4) Composite oxide film composed of trivalent chromium (5) Inorganic film such as oxide film composed of titanium oxide and zirconium oxide Can be applied.

In addition to the above inorganic coatings, for example, (6) thin film organic resin coating (0.1 to 2 μm) or organic composite silicate coating (7) chelate-forming organic coating such as tannic acid, phytic acid and phosphonic acid (8) A composite film in which an organic resin is mixed in the inorganic film of any one of the above (1), (2), and (3) can be applied. Among the above, a hardly soluble film containing silicon oxide (for example, an alkali silicate film) is most preferable from the viewpoint of suppressing white rust of zinc.

An organic resin may be incorporated into the above chemical conversion coating for the purpose of improving workability and corrosion resistance. As this organic resin, an epoxy resin, a urethane resin, an acrylic resin, an acrylic-ethylene copolymer, an acrylic-styrene copolymer, an alkyd resin, a polyester resin, an ethylene resin, or the like can be used.
These can be supplied as a water-soluble resin and / or a water-dispersible resin. Furthermore, in addition to these water-dispersible resins,
It is effective to use a water-soluble epoxy resin, a water-soluble phenol resin, a water-soluble butadiene rubber (SBR, NBR, MBR), a melamine resin, a blocked isocyanate, an oxazoline compound or the like as a crosslinking agent.

In the above chemical conversion coating, a polyphosphate salt is added as an additive for further improving the corrosion resistance.
Phosphates (eg, zinc phosphate, aluminum dihydrogen phosphate, zinc phosphite, etc.), molybdates, phosphomolybdates (aluminum phosphomolybdate, etc.), organic phosphoric acids and salts thereof (eg, phytic acid) , Phytate, phosphonic acid, phosphonate and their metal salts, alkali metal salts), organic inhibitors (for example, hydrazine derivatives, thiol compounds, dithiocarbamates, etc.), organic compounds (polyethylene glycol), etc. May be added to.

Further, as other additives, organic coloring pigments (for example, condensed polycyclic organic pigments, phthalocyanine organic pigments, etc.), coloring dyes (for example, organic solvent-soluble azo dyes, water-soluble azo metal dyes, etc.) ), Inorganic pigments (titanium oxide), chelating agents (thiols, etc.), conductive pigments (eg, metal powders such as zinc, aluminum, nickel, iron phosphide, antimony-doped tin oxide, etc.), coupling agents (eg, A silane coupling agent, a titanium coupling agent, etc.), a melamine / cyanuric acid adduct, etc. can be added.

Further, in order to prevent blackening (a kind of oxidation phenomenon of the plating surface) under the use environment of the organic coated steel sheet, these chemical conversion treatment films are coated with iron group metal ions (Ni ion, C ion).
O ions, Fe ions), preferably Ni ions may be added. In this case, the desired effect can be obtained if the concentration of the iron group metal ion is 1/10000 mol or more with respect to 1 mol of the (β) alkaline earth metal ion in the treatment composition. The upper limit of the concentration of the iron group metal ion is not particularly specified, but it is set to such an extent that the corrosion resistance is not affected as the concentration increases. The thickness of these chemical conversion coatings is 3 μm or less. This is because if the film thickness exceeds 3 μm, the workability and conductivity decrease. The lower limit is not particularly defined, but may be set to a film thickness that is effective in improving the corrosion resistance.

Next, the case of applying a chromate film as the chemical conversion film will be described. The chromate film may be any of a reactive chromate treatment film, an electrolytic chromate treatment film, and a coating type chromate treatment film.
The coating-type chromate treatment film contains a partially reduced chromic acid aqueous solution as a main component, and if necessary, the following
It can be obtained by using a chromate treatment liquid to which one or more selected from the above components are added, applying this chromate treatment liquid to a plated steel sheet, and drying without washing with water.

Water-soluble or water-dispersible organic resins such as acrylic resins and polyester resins Colloids and / or powders of oxides such as silica, alumina, titania, zirconia, and zinc oxide Molybdic acid, tungstic acid, vanadic acid, etc. Acids and / or salts thereof Phosphoric acids such as phosphoric acid and polyphosphoric acid Zirconium fluoride, silicofluoride, fluorides such as titanium fluoride and phosphoric acid fluoride Metal ions such as zinc ion, nickel ion, cobalt ion and iron ion Phosphorylation Conductive fine powder of iron, antimony-doped tin oxide, etc. Hydrogen fluoride Silane coupling agent

In this coating type chromate treatment, 6
In order to suppress the content of valent Cr, it is effective to increase the reduction rate in the chromate treatment liquid. Particularly, it is effective to use a chromate treatment liquid in which the ratio of hexavalent chromium in the treatment liquid is reduced so that the ratio of hexavalent Cr / total Cr (solid content) is 0.1 or less, preferably 0.01 or less. Is. As a method for adjusting such a chromate treatment liquid, an excess oxalic acid and / or an oxycarboxylic acid as a reducing agent is added to a chromic anhydride aqueous solution to increase the reduction rate, and at the same time, a reduction product is obtained by increasing the pH. In order to prevent trivalent Cr from precipitating, it is effective to lower the pH with phosphoric acid or the like, and thereby a chromate film containing trivalent Cr as a main component can be stably obtained. In the coating type chromate treatment, the treatment liquid is usually applied by a roll coater method, but it is also possible to adjust the coating amount by an air knife method or a roll drawing method after applying by a dipping method or a spray method.

The electrolytic chromate treatment film contains, for example, a partially reduced chromic acid aqueous solution and sulfuric acid as main components, and if necessary, metal ions (for example, Zn, Ni, Co, Fe, M).
g, Mn, Al, Ca, etc.), oxide colloids and / or fine powder (silica, alumina, titania, zirconia, magnesia, zinc oxide, tin oxide, antimony oxide, etc.) chlorine ion, fluorine ion, nitric acid Ion, anion such as phosphate ion, one or more selected from zirconium fluoride, silicofluoride, titanium fluoride, boron fluoride fluoride, fluoride such as phosphoric acid fluoride polyethylene glycol, organic compound such as water-based acrylic resin Is added, pH 1
It can be obtained by cathodic electrolyzing a plated steel sheet with a quantity of electricity of 0.5 to 40 C / dm ² at a temperature of 30 to 70 ° C. using a chromate treatment solution adjusted to 5 to 5.

The reactive chromate film contains, for example, chromic anhydride and sulfuric acid as main components, and the content of trivalent Cr in the total Cr is 50% by weight or less, preferably 20 to 35% by weight. A chromate treatment liquid to which an appropriate amount of metal ions (for example, Zn ions, Co ions, Ni ions, Fe ions, etc.) and other mineral acids (for example, phosphoric acid, hydrochloric acid, hydrofluoric acid, etc.) are added is used. It can be obtained by treating a plated steel sheet with a chromate treatment liquid.

The amount of these chromate films deposited is from 1 to 1000 mg / m ^{2 in} terms of metallic chromium, preferably from 5 to 5.
200 mg / m ² , particularly preferably 10-100 mg /
m ² If the adhered amount is less than 1 mg / m ² , the corrosion resistance is insufficient, while if the adhered amount exceeds 1000 mg / m ² , problems such as crack formation in the chromate film and deterioration of weldability occur.

Next, the organic coating formed on the chemical conversion coating will be described. In the present invention, the organic coating formed on the chemical conversion coating is an active hydrogen-containing compound (B) comprising a film-forming organic resin (A) and a hydrazine derivative (C) in which some or all of the compounds have active hydrogen. And a calcium phosphate (a) and a calcium compound (b) and a solid lubricant (c), if necessary, to give a film thickness of 0.1. It is an organic film of 5 μm.

The type of film-forming organic resin (A) is
By reacting some or all of the compounds with the active hydrogen-containing compound (B) consisting of the hydrazine derivative (C) having active hydrogen, the active hydrogen-containing compound (B) is added or condensed to the film-forming organic resin. There is no particular limitation as long as it is a resin that can bond and form a film appropriately. Examples of the film-forming organic resin (A) include epoxy resin,
Examples include modified epoxy resins, polyurethane resins, polyester resins, alkyd resins, acrylic copolymer resins, polybutadiene resins, phenol resins, and adducts or condensates of these resins. They can be used alone or in combination of two or more.

As the film-forming organic resin (A),
The epoxy group-containing resin (D) having an epoxy group in the resin is particularly preferable from the viewpoints of reactivity, easiness of reaction, anticorrosion and the like. As the epoxy group-containing resin (D), a part or all of the compounds react with the active hydrogen-containing compound (B) consisting of a hydrazine derivative (C) having active hydrogen to give a film-forming organic resin an active hydrogen-containing compound. There is no particular limitation as long as (B) is a resin that can be bonded by a reaction such as addition or condensation and can appropriately form a film. For example, an epoxy resin, a modified epoxy resin, an acrylic resin copolymerized with an epoxy group-containing monomer Examples thereof include copolymer resins, epoxy group-containing polybutadiene resins, epoxy group-containing polyurethane resins, and adducts or condensates of these resins. These epoxy group-containing resins may be used alone or in combination. The above can be mixed and used. Among these epoxy group-containing resins (D), epoxy resin and modified epoxy resin are particularly preferable from the viewpoint of adhesion to the plating surface and corrosion resistance.

The above-mentioned epoxy resin is obtained by reacting a polyphenol such as bisphenol A, bisphenol F, novolac type phenol and the like with an epihalohydrin such as epichlorohydrin to introduce a glycidyl group, or a reaction product of this glycidyl group introduction. Further, there may be mentioned aromatic epoxy resins obtained by reacting polyphenols to increase the molecular weight, further aliphatic epoxy resins, alicyclic epoxy resins, etc. One of these may be used alone, or two or more of them may be mixed. Can be used.
It is preferable that these epoxy resins have a number average molecular weight of 1500 or more, particularly when film forming properties at low temperatures are required.

Examples of the modified epoxy resin include resins obtained by reacting various modifying agents with the epoxy groups or hydroxyl groups in the epoxy resin, and examples thereof include epoxy ester resins obtained by reacting a drying oil fatty acid, acrylic acid or Examples thereof include epoxy acrylate resin modified with a polymerizable unsaturated monomer component containing methacrylic acid and the like, and urethane modified epoxy resin reacted with an isocyanate compound.

As the acrylic copolymer resin copolymerized with the above epoxy group-containing monomer, an unsaturated monomer having an epoxy group and a polymerizable unsaturated monomer component containing an acrylate ester or a methacrylic acid ester as a solution are prepared as a solution. A resin synthesized by a polymerization method, an emulsion polymerization method, a suspension polymerization method, or the like can be given.

As the above-mentioned polymerizable unsaturated monomer component,
For example, methyl (meth) acrylate, ethyl (meth)
Acrylate, propyl (meth) acrylate, n-,
C1-24 alkyl ester of acrylic acid or methacrylic acid such as iso- or tert-butyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, decyl (meth) acrylate, lauryl (meth) acrylate; Acrylic acid, methacrylic acid, styrene, vinyltoluene, acrylamide, acrylonitrile, N-methylol (meth) acrylamide, C1-4 alkyl ether compound of N-methylol (meth) acrylamide; N, N-diethylaminoethyl methacrylate and the like. it can.

Further, as the unsaturated monomer having an epoxy group, glycidyl methacrylate, glycidyl acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate and the like are used as long as they have an epoxy group and a polymerizable unsaturated group. There are no restrictions. Further, the acrylic copolymer resin copolymerized with the epoxy group-containing monomer may be a resin modified with a polyester resin, an epoxy resin, a phenol resin, or the like.

Particularly preferable as the epoxy resin is a resin having a chemical structure represented by the following formula (1), which is a reaction product of bisphenol A and epihalohydrin, and this epoxy resin is particularly excellent in corrosion resistance. preferable.

[Chemical 3] A method for producing such a bisphenol A type epoxy resin is widely known in the art. In the above chemical structural formula, q is 0 to 50, preferably 1 to 40, and particularly preferably 2 to 20. The film-forming organic resin (A) may be any of organic solvent-soluble type, organic solvent-dispersed type, water-soluble type, and water-dispersed type.

In the present invention, the purpose is to add a hydrazine derivative into the molecule of the film-forming organic resin (A), and therefore at least a part (preferably all) of the active hydrogen-containing compound (B) is active hydrogen. It is necessary that the hydrazine derivative (C) has

When the film-forming organic resin (A) is an epoxy group-containing resin, examples of the active hydrogen-containing compound (B) that reacts with the epoxy group include the compounds shown below. You can use more than one seed,
Also in this case, at least a part (preferably all) of the active hydrogen-containing compound (B) needs to be a hydrazine derivative having active hydrogen.・ Hydrazine derivatives having active hydrogen ・ Primary or secondary amine compounds having active hydrogen ・ Organic acids such as ammonia and carboxylic acid ・ Hydrogen halides such as hydrogen chloride ・ Alcohols, thiols ・ Active hydrogen Quaternary chlorinating agent which is a hydrazine derivative or a mixture of a tertiary amine and an acid

Examples of the hydrazine derivative (C) having active hydrogen include the following. Carbohydrazide, propionic acid hydrazide, salicylic acid hydrazide, adipic acid dihydrazide, sebacic acid dihydrazide, dodecanoic acid dihydrazide, isophthalic acid dihydrazide, thiocarbohydrazide, 4,4'-oxybisbenzenesulfonyl hydrazide, benzophenone hydrazone, aminopolyacrylamide, etc. Compounds; pyrazole compounds such as pyrazole, 3,5-dimethylpyrazole, 3-methyl-5-pyrazolone, and 3-amino-5-methylpyrazole;

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-methyl-8-hydroxytriazolopyridazine, 6-phenyl-8-hydroxytriazolopyridazine, 5-hydroxy-7-methyl-1,3,8-triazind Triazole compounds such as lysine;

5-phenyl-1,2,3,4-tetrazole, 5-mercapto-1-phenyl-1,2,
Tetrazole compounds such as 3,4-tetrazole; 5-Amino-2-mercapto-1,3,4-thiadiazole, 2,5-dimercapto-1,3,4-thiadiazole and other thiadiazole compounds; maleic hydrazide, 6- Pyridazine compounds such as methyl-3-pyridazone, 4,5-dichloro-3-pyridazone, 4,5-dibromo-3-pyridazone, 6-methyl-4,5-dihydro-3-pyridazone

Among these, 5-membered ring or 6-membered ring
Pyrazole compounds and triazole compounds having a membered ring cyclic structure and having a nitrogen atom in the cyclic structure are particularly preferable. These hydrazine derivatives can be used alone or in combination of two or more.

Typical examples of the above-mentioned amine compound having active hydrogen that can be used as a part of the active hydrogen-containing compound (B) include the following. A primary amino group of an amine compound containing one secondary amino group such as diethylenetriamine, hydroxyethylaminoethylamine, ethylaminoethylamine, and methylaminopropylamine and one or more primary amino groups is converted into a ketone, an aldehyde, or a carboxyl group. Acid and eg 1
A compound modified by heating to a temperature of about 00 to 230 ° C. to give an aldimine, ketimine, oxazoline or imidazoline;

Diethylamine, diethanolamine, di-n- or -iso-propanolamine, N
-Secondary monoamines such as methylethanolamine and N-ethylethanolamine; secondary amine-containing compounds obtained by adding a monoalkanolamine such as monoethanolamine and a dialkyl (meth) acrylamide by a Michael addition reaction ; Monoethanolamine, neopentanolamine,
2-aminopropanol, 3-aminopropanol, 2
A compound in which the primary amino group of an alkanolamine such as -hydroxy-2 '(aminopropoxy) ethyl ether is modified with ketimine;

The above-mentioned quaternary chlorinating agent which can be used as a part of the active hydrogen-containing compound (B) is used because the hydrazine derivative having no active hydrogen or the tertiary amine itself has no reactivity with the epoxy group. Is a mixture with an acid so that it can react with an epoxy group. The quaternary chlorinating agent reacts with the epoxy group in the presence of water, if necessary, to form a quaternary salt with the epoxy group-containing resin.

The acid used to obtain the quaternary chlorinating agent is
Any of organic acids such as acetic acid and lactic acid, and inorganic acids such as hydrochloric acid may be used. Examples of the hydrazine derivative having no active hydrogen used to obtain the quaternary chlorinating agent include, for example, 3,
6-dichloropyridazine and the like, and examples of the tertiary amine include dimethylethanolamine, triethylamine, trimethylamine, triisopropylamine, methyldiethanolamine and the like.

The reaction product of the film-forming organic resin (A) with the active hydrogen-containing compound (B) consisting of a hydrazine derivative (C) in which some or all of the compounds have active hydrogen is the film-forming organic resin (A). And the active hydrogen-containing compound (B) at 10 to 300 ° C., preferably 50 to 150 ° C. and about 1 to 8
It is obtained by reacting for about time.

This reaction may be carried out by adding an organic solvent, and the type of organic solvent 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. , Alcohols and ethers containing hydroxyl groups such as propylene glycol, propylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether; esters such as ethyl acetate, butyl acetate, ethylene glycol monobutyl ether acetate; toluene, xylene Such as aromatic hydrocarbons It can be used one or two or more thereof. Of these, ketone-based or ether-based solvents are particularly preferable from the viewpoints of solubility with epoxy resin, film-forming property, and the like.

The compounding ratio of the film-forming organic resin (A) and the active hydrogen-containing compound (B) consisting of a hydrazine derivative (C) in which some or all of the compounds have active hydrogen is such that the film-forming organic resin is a solid content. 0.5 to 20 parts by weight of the active hydrogen-containing compound (B) based on 100 parts by weight of the resin (A),
Particularly preferably, the amount is 1.0 to 10 parts by weight.

When the film-forming organic resin (A) is the epoxy group-containing resin (D), the mixing ratio of the epoxy group-containing resin (D) and the active hydrogen-containing compound (B) is The ratio [the number of active hydrogen groups / the number of epoxy groups] of the number of active hydrogen groups of the compound (B) and the number of epoxy groups of the epoxy group-containing resin (D) is 0.01 to 10, more preferably 0.1 to 8, It is more preferable to set it to 0.2 to 4 from the viewpoint of corrosion resistance and the like.

The ratio of the hydrazine derivative (C) having active hydrogen in the active hydrogen-containing compound (B) is 1
It is suitable to be 0 to 100 mol%, more preferably 30 to 100 mol%, and further preferably 40 to 100 mol%. If the proportion of the hydrazine derivative (C) having active hydrogen is less than 10 mol%, a sufficient rust preventive function cannot be imparted to the organic film, and the obtained rust preventive effect is obtained by simply mixing the film forming organic resin and the hydrazine derivative. It is almost the same as when it is used.

In the present invention, in order to form a dense barrier film, it is desirable to mix a curing agent in the resin composition and heat-cure the organic film. As the curing method for forming the resin composition film, (1) a curing method utilizing a urethanization reaction between an isocyanate and a hydroxyl group in the base resin, (2) a method selected from melamine, urea and benzoguanamine 1 to 5 carbon atoms in part or all of the methylol compound obtained by reacting formaldehyde with at least one species
The curing method utilizing the etherification reaction between the alkyl etherified amino resin obtained by reacting the monohydric alcohol with the hydroxyl group in the base resin is suitable. It is particularly preferable to use the urethanization reaction as the main reaction.

The polyisocyanate compound used in the curing method (1) above is an aliphatic, alicyclic (including heterocyclic) or aromatic isocyanate compound having at least two isocyanate groups in one molecule, or an aromatic isocyanate compound thereof. It is a compound obtained by partially reacting a compound with a polyhydric alcohol. Examples of such polyisocyanate compounds include the following. m- or p-phenylene diisocyanate, 2,
4- or 2,6-tolylene diisocyanate, o- or p-xylylene diisocyanate, hexamethylene diisocyanate, dimer acid diisocyanate, isophorone diisocyanate

The above compounds alone 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, diether). Compounds in which at least two isocyanates remain in one molecule, which are reaction products with hexahydric alcohols such as pentaerythritol, etc. These polyisocyanate compounds may be used alone or in combination of two or more. Can be used.

Examples of the protective agent (blocking agent) for the polyisocyanate compound include aliphatic monoalcohols such as methanol, ethanol, propanol, butanol and octyl alcohol, and monoethers of ethylene glycol and / or diethylene glycol, for example, Methyl, ethyl, propyl (n-, iso), butyl (n-, iso, se)
c) etc. monoether phenol, aromatic alcohols such as cresol acetoxime, oximes such as methyl ethyl ketone oxime, etc. can be used, and at least at room temperature by reacting one or more of these with the polyisocyanate compound. It is possible to obtain a polyisocyanate compound stably protected with.

Such a polyisocyanate compound (E) as a curing agent is (A) / (E) = 95/5 to 55/45 (weight ratio of non-volatile content) to the film-forming organic resin (A), Preferably (A) / (E) = 90/10
It is suitable to mix in the ratio of 65/35. The polyisocyanate compound has water absorbability, which is (A) /
If it is blended in excess of (E) = 55/45, the adhesion of the organic film will be deteriorated. Furthermore, when topcoating is performed on the organic film, the unreacted polyisocyanate compound migrates into the coating film, causing inhibition of curing of the coating film and poor adhesion. From this point of view, it is preferable that the amount of the polyisocyanate compound (E) is (A) / (E) = 55/45 or less.

The film-forming organic resin (A) is sufficiently crosslinked by the addition of the above-mentioned crosslinking agent (curing agent).
Further, it is desirable to use a known curing accelerating catalyst in order to increase the low temperature crosslinkability. As the curing acceleration catalyst, for example, N-ethylmorpholine, dibutyltin dilaurate, cobalt naphthenate, stannous chloride, zinc naphthenate, bismuth nitrate or the like can be used. Further, for example, when an epoxy group-containing resin is used as the film-forming organic resin (A), in order to improve the physical properties such as adhesion, a known acrylic resin, alkyd,
A resin such as polyester may be mixed and used.

In the present invention, zinc phosphate and / or aluminum phosphate (a) is used as an anticorrosive additive in the organic film.
Is compounded. Zinc phosphate and aluminum phosphate compounded in the organic film are not particularly limited in terms of the skeleton and the degree of condensation of phosphate ions, and any of normal salts, dihydrogen salts, monohydrogen salts and phosphites can be used. Well, the regular salts include all condensed phosphates such as polyphosphates as well as orthophosphates. For example, LF Bosei ZP-DL manufactured by Kikuchi Color Co., Ltd. can be used as zinc phosphate, and K-WHITE manufactured by Teika Co., Ltd. can be used as aluminum phosphate.

These zinc phosphates and aluminum phosphates are dissociated into phosphate ions by hydrolysis in a corrosive environment, and form a protective film by causing a complex formation reaction with the eluted metal. In the present invention, the anticorrosion mechanism when zinc phosphate and / or aluminum phosphate (a) is added to the organic film is as described above, and in the present invention, a specific chelate-forming compound which is a film-forming organic resin is formed. Resin and zinc phosphate and / or aluminum phosphate (a)
By compounding with, the effect of inhibiting corrosion at the anode reaction part by the chelate-forming resin and zinc phosphate and / or
Alternatively, the corrosion inhibiting effect of aluminum phosphate (a) is combined to provide an extremely excellent anticorrosion effect.

The compounding amount of zinc phosphate and / or aluminum phosphate (a) in the organic resin film is a part of the reaction product (the film forming organic resin (A) or 1 to 100 parts by weight (solid content), preferably 100 parts by weight (solid content) of a reaction product with an active hydrogen-containing compound (B) consisting of a hydrazine derivative (C) in which all compounds have active hydrogen. Is 5 to 80
By weight (solid content), more preferably 10 to 50 parts by weight (solid content). When the amount of zinc phosphate and / or aluminum phosphate (a) is less than 1 part by weight, the effect of improving corrosion resistance after alkali degreasing is small. On the other hand, if the blending amount exceeds 100 parts by weight, the corrosion resistance decreases, which is not preferable.

Further, in the present invention, particularly excellent corrosion resistance can be obtained by adding the calcium compound (b) together with the zinc phosphate and / or the aluminum phosphate (a) in the organic film. That is, zinc phosphate and /
Alternatively, by adding the aluminum phosphate (a) and the calcium compound (b) in combination, a particularly excellent anticorrosion effect can be obtained by the above-described composite rustproof mechanism of both.

The calcium compound (b) may be any of calcium oxide, calcium hydroxide and calcium salt, and one or more of these may be used. In addition, the type of calcium salt is not particularly limited, and in addition to single salts containing only calcium as a cation such as calcium silicate, calcium carbonate, and calcium phosphate,
A double salt containing calcium and a cation other than calcium, such as calcium phosphate / zinc and calcium phosphate / magnesium, may be used.

The calcium compound elutes preferentially over the plated metal in a corrosive environment, so that it causes a complex formation reaction with phosphate ions without triggering the elution of the plated metal to form a dense and sparingly soluble protective film. It is thought to form and suppress the corrosion reaction.

When zinc phosphate and / or aluminum phosphate (a) and calcium compound (b) are added in combination to the organic film, the compounding amount is a reaction product (film forming film) which is a resin composition for film formation. 100 parts by weight (solid content) of the reaction product of the organic resin (A) and the active hydrogen-containing compound (B) consisting of a hydrazine derivative (C) in which some or all of the compounds have active hydrogen), and phosphoric acid The total compounding amount of zinc and / or aluminum phosphate (a) and calcium compound (b) is 1 to 100 parts by weight (solid content), preferably 5 to 80 parts by weight (solid content), and phosphorus. The weight ratio (a) / (b) of the compounding amount (solid content) of zinc acid and / or aluminum phosphate (a) and calcium compound (b) is 99/1 to 1/99, preferably 95/5 to 40. / 60 The preferably 90/10
-60/40.

When the total compounding amount of zinc phosphate and / or aluminum phosphate (a) and calcium compound (b) is less than 1 part by weight, the effect of improving corrosion resistance after alkali degreasing is small. On the other hand, if the total blending amount exceeds 100 parts by weight, the corrosion resistance decreases, which is not preferable. Further, the weight ratio (a) / of the compounding amount (solid content) of zinc phosphate and / or aluminum phosphate (a) and calcium compound (b) /
When (b) is less than 1/99, corrosion resistance is poor, while when the weight ratio (a) / (b) exceeds 99/1, zinc phosphate and / or aluminum phosphate (a) and calcium compound (b) The effect of combined addition cannot be sufficiently obtained.

In addition to the above-mentioned rust-preventive additives, the organic film contains fine oxide particles (eg, silicon oxide, aluminum oxide, zirconium oxide, titanium oxide, cerium oxide, antimony oxide) as a corrosion inhibitor. , Molybdate, phosphomolybdate (for example, aluminum phosphomolybdate, etc.), organic phosphoric acid and salts thereof (for example, phytic acid, phytate, phosphonic acid, phosphonate, and metal salts thereof, alkali metal) Salts, alkaline earth metal salts, etc.), organic inhibitors (eg, hydrazine derivatives, thiol compounds, dithiocarbamates, etc.)
Etc. can be added.

If necessary, a solid lubricant (c) may be added to the organic coating for the purpose of improving the workability of the coating. Examples of the solid lubricant applicable to the present invention include the following. (1) Polyolefin wax, paraffin wax:
For example, polyethylene wax, synthetic paraffin, natural paraffin, microwax, chlorinated hydrocarbon, etc. (2) Fluorine resin fine particles: For example, polyfluoroethylene resin (polytetrafluoroethylene resin etc.), polyvinyl fluoride resin, polyvinylidene fluoride Resin, etc.

In addition to the above, fatty acid amide compounds (for example, stearic acid amide, palmitic acid amide,
Methylene bis stearamide, ethylene bis stearamide, oleic acid amide, esyl acid amide, alkylene bis fatty acid amide, etc.), metallic soaps (eg calcium stearate, lead stearate, calcium laurate, calcium palmitate, etc.), metal Sulfides (molybdenum disulfide, tungsten disulfide), graphite,
Fluorinated graphite, boron nitride, polyalkylene glycol,
You may use alkali metal sulfate etc.

Among the above solid lubricants, especially polyethylene wax, fluororesin fine particles (among others, poly 4
Fluorinated ethylene resin fine particles) are suitable. As the polyethylene wax, for example, Ceridust 9615A, Ceridust 3715, Ceridust 3 manufactured by Hoechst Co.
620, Ceridust 3910, Sun Wax 131-P, San Wax 161-P manufactured by Sanyo Kasei Co., Ltd., Chemipearl W-100, Chemipearl W-200, Chemipearl W-500, Chemipearl W-500 manufactured by Mitsui Petrochemical Co., Ltd.
W-800, Chemipearl W-950 and the like can be used.

Further, as the fluororesin fine particles, tetrafluoroethylene fine particles are most preferable, and for example, Lubron L-2 and Lubron L- manufactured by Daikin Industries, Ltd.
5, MP1100, MP12 manufactured by Mitsui DuPont Co., Ltd.
00, full-on dispersion AD1, full-on dispersion AD2, full-on L141J, full-on L15 manufactured by Asahi IC Fluoropolymers Co., Ltd.
0J and FLUON L155J are suitable. Further, among these, a particularly excellent lubricating effect can be expected by using a combination of polyolefin wax and tetrafluoroethylene fine particles.

The amount of the solid lubricant (c) blended in the organic film is such that the reaction product (the film-forming organic resin (A) and a part or all of the compounds of the resin composition for film formation contains active hydrogen). Reaction product with active hydrogen-containing compound (B) consisting of hydrazine derivative (C)) 100 parts by weight (solid content)
With respect to 1 to 80 parts by weight (solid content), preferably 3 to
40 parts by weight (solid content). When the blending amount of the solid lubricant (c) is less than 1 part by weight, the lubricating effect is poor, while when the blending amount exceeds 80 parts by weight, the coating property is deteriorated, which is not preferable.

The organic coating film of the organic coated steel sheet of the present invention is usually an active hydrogen-containing compound (B) comprising a film-forming organic resin (A) and a hydrazine derivative (C) in which some or all of the compounds have active hydrogen. A reaction product with (resin composition) as a main component, and zinc phosphate and / or aluminum phosphate (a) is added thereto, and if necessary,
A calcium compound (b), a solid lubricant (c), a curing agent and the like are added, and if necessary, as an additive, an organic coloring pigment (for example, a condensed polycyclic organic pigment, a phthalocyanine organic pigment, etc.) is added. ), Colored dyes (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) , Metal powders such as nickel, iron phosphide, antimony-doped tin oxide, etc.), coupling agents (eg, silane coupling agents, titanium coupling agents, etc.), melamine
A cyanuric acid adduct or the like can be added.

The coating composition for forming a film containing the above main component and additional components usually contains a solvent (organic solvent and / or water), and a neutralizing agent or the like is added if necessary. . The organic solvent is not particularly limited as long as it can dissolve or disperse the reaction product of the film-forming organic resin (A) and the active hydrogen-containing compound (B) and can be adjusted as a coating composition, and for example, Various organic solvents exemplified above can be used. The above-mentioned neutralizing agent is added as necessary in order to neutralize the film-forming organic resin (A) to make it aqueous, and when the film-forming organic resin (A) is a cationic resin. Acids such as acetic acid, lactic acid and formic acid can be used as neutralizing agents.

The organic coating as described above is formed on the chemical conversion coating formed on the surface of the zinc-plated steel sheet or the aluminum-plated steel sheet. The dry film thickness of the organic film is 0.1 to 5 μm, preferably 0.3 to 3 μm, and more preferably 0.5 to 2 μm. If the organic film thickness is less than 0.1 μm, the corrosion resistance is insufficient, whereas if the organic film thickness exceeds 5 μm, the conductivity and workability deteriorate.

Next, a method for manufacturing the organic coated steel sheet of the present invention will be described. In the organic coated steel sheet of the present invention, after the surface of the zinc-based plated steel sheet or the aluminum-based plated steel sheet is subjected to chemical conversion treatment, the above-mentioned film-forming organic resin (A) and a part or all of the compounds have active hydrogen in the upper layer. A reaction product (preferably a main component) of the hydrazine derivative (C) with the active hydrogen-containing compound (B),
Produced by applying a coating composition containing zinc phosphate and / or aluminum phosphate (a), and optionally a calcium compound (b), a solid lubricant (c), etc., and drying by heating. To be done. The surface of the plated steel sheet may be subjected to alkali degreasing treatment as needed before applying the treatment liquid, and further subjected to pretreatment such as surface conditioning treatment in order to improve adhesion and corrosion resistance.

When a chemical conversion treatment film containing no hexavalent chromium is formed as the chemical conversion treatment film, the method of coating the treatment solution on the surface of the plated steel sheet may be any of a coating method, a dipping method and a spray method. Any coating means such as a roll coater (3 roll system, 2 roll system, etc.), a squeeze coater, a die coater, etc. may be used. It is also possible to adjust the coating amount, make the appearance uniform, and make the film thickness uniform by an air knife method or a roll squeezing method after the coating treatment with a squeeze coater, the dipping treatment, and the spray treatment.

After coating the treatment liquid as described above, it is washed with water if necessary and then dried by heating. The method of heating and drying the coated treatment liquid is arbitrary, and, for example, a dryer, a hot air oven, a high frequency induction heating oven, an infrared oven or the like can be used. This heat drying treatment is performed at an ultimate plate temperature of 40 to 350 ° C., preferably 80 to 200.
C., more preferably in the range of 80 to 160.degree. If the heating and drying temperature is lower than 40 ° C, a large amount of water remains in the film, resulting in insufficient corrosion resistance. On the other hand, if the heating and drying temperature is higher than 350 ° C., not only is it uneconomical, but also the film is apt to have defects and the corrosion resistance is lowered.

On the other hand, when the chemical conversion treatment film is a chromate film, any of the above-mentioned coating type, electrolytic type or reaction type chromate treatment is carried out, and if necessary, after washing with water,
Heat drying. As a method for coating the surface of the plated steel sheet with the treatment liquid, any of a coating method, a dipping method and a spray method may be used, and a roll coater (3
Any coating means such as a roll system, a two roll system, etc.), a squeeze coater, a die coater or the like may be used. It is also possible to adjust the coating amount, make the appearance uniform, and make the film thickness uniform by an air knife method or a roll squeezing method after the coating treatment with a squeeze coater, the dipping treatment, and the spray treatment.

The heating and drying method after the chromate treatment is arbitrary, and means such as a dryer, a hot air oven, a high frequency induction heating oven, an infrared oven or the like can be used. This heat drying treatment is performed at an ultimate plate temperature of 40 to 150 ° C, preferably 8
It is preferably carried out in the range of 0 to 140 ° C. If the heating and drying temperature is lower than 40 ° C, a large amount of water remains in the film, resulting in insufficient corrosion resistance. On the other hand, if the heating and drying temperature exceeds 150 ° C., not only is it uneconomical, but defects such as cracks are likely to occur in the coating, and the corrosion resistance decreases.

After the chemical conversion treatment film is formed on the surface of the zinc-based plated steel sheet or the aluminum-based plated steel sheet as described above, the coating composition for forming an organic film is applied to the upper layer thereof. As a method of applying the coating composition, any method such as a coating method, a dipping method, and a spray method can be adopted. As a coating method, any method such as a roll coater (3 roll system, 2 roll system, etc.), a squeeze coater, a die coater or the like may be used. Further, it is possible to adjust the coating amount, make the appearance uniform, and make the film thickness uniform by an air knife method or a roll squeezing method after the coating treatment with a squeeze coater or the like, the dipping treatment or the spray treatment.

After application of the coating composition, heating and drying are usually carried out without washing with water, but a washing step may be carried out after application of the coating composition. A dryer, hot air oven, high-frequency induction heating oven, infrared oven, or the like can be used for the heating and drying treatment. The heat treatment is performed at an ultimate plate temperature of 50 to 350 ° C.
It is desirable to carry out in the range of 80 ° C to 250 ° C. If the heating temperature is lower than 50 ° C, a large amount of water remains in the film, resulting in insufficient corrosion resistance. Also, the heating temperature is 350 ℃
If it exceeds, not only is it uneconomical, but there is a possibility that defects may occur in the film and the corrosion resistance may be reduced.

The present invention includes a steel sheet having the above-mentioned organic coating on both sides or one side. Therefore, examples of the form of the steel sheet of the present invention include the following. (1) One side: plating film-chemical conversion film-organic film, one side: plating film (2) One surface: plating film-chemical conversion film-organic film, one side: plating film-chemical conversion film (3) Both sides: plating film- Chemical conversion coating-organic coating (4) One side: plating coating-chemical conversion coating-organic coating, one side: plating coating-organic coating

[0104]

[Example] Resin composition for organic film formation (reaction product)
Was synthesized as follows. [Synthesis Example 1] 1870 parts of EP828 (produced by Yuka Shell Epoxy Co., Ltd., epoxy equivalent: 187) and bisphenol A91
2 parts, tetraethylammonium bromide 2 parts, and methyl isobutyl ketone 300 parts were charged into a four-necked flask, heated to 140 ° C. and reacted for 4 hours to obtain an epoxy resin having an epoxy equivalent of 1391 and a solid content of 90%. To this, ethylene glycol monobutyl ether 150
After adding 0 part, the mixture was cooled to 100 ° C., 96 parts of 3,5-dimethylpyrazole (molecular weight 96) and 129 parts of dibutylamine (molecular weight 129) were added, and the mixture was reacted for 6 hours until the epoxy group disappeared. While cooling, 205 parts of methyl isobutyl ketone was added to obtain a pyrazole-modified epoxy resin having a solid content of 60%. This is a resin composition (1)
And This resin composition (1) is a reaction product of a film-forming organic resin (A) and an active hydrogen-containing compound containing 50 mol% of a hydrazine derivative (C) having active hydrogen.

[Synthesis Example 2] 4000 parts of EP1007 (produced by Yuka Shell Epoxy Co., Ltd., epoxy equivalent: 2000) and 2239 parts of ethylene glycol monobutyl ether were placed in a four-necked flask, and the temperature was raised to 120 ° C. and completely completed in 1 hour. The epoxy resin was dissolved. This is cooled to 100 ° C., and 3-amino-1,2,4-triazole (molecular weight 8
After adding 168 parts of 4) and reacting for 6 hours until the epoxy group disappeared, 540 parts of methyl isobutyl ketone was added while cooling to obtain a triazole-modified epoxy resin having a solid content of 60%. This is designated as resin composition (2). This resin composition (2) contains 100 mol of a film-forming organic resin (A) and a hydrazine derivative (C) having active hydrogen.
% Active hydrogen-containing compound.

[Synthesis Example 3] 222 parts of isophorone diisocyanate (isocyanate equivalent 111) and 34 parts of methyl isobutyl ketone were charged into a four-necked flask, and 30 to 4 parts were charged.
Keep at 0 ° C methyl ethyl ketoxime (molecular weight 87) 8
After dropping 7 parts over 3 hours, the temperature was kept at 40 ° C. for 2 hours to obtain a partially blocked isocyanate having an isocyanate equivalent of 309 and a solid content of 90%.

Next, 14828 parts of EP828 (manufactured by Yuka Shell Epoxy Co., epoxy equivalent 187), 684 parts of bisphenol A and 1 part of tetraethylammonium bromide.
Parts and 241 parts of methyl isobutyl ketone were charged into a four-necked flask, heated to 140 ° C. and reacted for 4 hours to obtain an epoxy resin having an epoxy equivalent of 1090 and a solid content of 90%. To this product, 1000 parts of methyl isobutyl ketone was added and cooled to 100 ° C. to give 3-mercapto-1,
After adding 202 parts of 2,4-triazole (molecular weight 101) and reacting for 6 hours until the epoxy group disappears, 230 parts of the above partially blocked isocyanate having a solid content of 90% is added.
It was confirmed that the isocyanate group had disappeared by adding a portion and reacting at 100 ° C. for 3 hours. Further, 461 parts of ethylene glycol monobutyl ether was added to obtain a triazole-modified epoxy resin having a solid content of 60%. This is referred to as a resin composition (3). This resin composition (3) is a reaction product of a film-forming organic resin (A) and an active hydrogen-containing compound containing 100 mol% of a hydrazine derivative (C) having active hydrogen.

[Synthesis Example 4] 1870 parts of EP828 (manufactured by Yuka Shell Epoxy Co., epoxy equivalent 187), 912 parts of bisphenol A, 2 parts of tetraethylammonium bromide and 300 parts of methyl isobutyl ketone were charged in a four-necked flask and heated to 140 ° C. Raise the temperature and react for 4 hours,
An epoxy resin having an epoxy equivalent of 1391 and a solid content of 90% was obtained. To this, 1500 parts of ethylene glycol monobutyl ether was added and then cooled to 100 ° C., 258 parts of dibutylamine (molecular weight 129) was added, and the reaction was allowed to proceed for 6 hours until the epoxy group disappeared, then methylisobutyl was added while cooling. Add 225 parts of ketone and solid content 60%
The epoxy amine adduct of was obtained. This is designated as resin composition (4). This resin composition (4) is a reaction product of a film-forming organic resin (A) and an active hydrogen-containing compound that does not contain a hydrazine derivative (C) having active hydrogen.

A curing agent was added to the resin compositions (1) to (4) synthesized as described above to prepare resin compositions (coating compositions) shown in Table 3. These coating compositions are appropriately blended with zinc phosphate and / or aluminum phosphate shown in Table 4, calcium compounds shown in Table 5, and solid lubricants shown in Table 6, and then dispersed in a paint dispersing machine (sand grinder).
Was used to disperse for a required time to obtain a desired coating composition.

[Example 1] In order to obtain an organic coated steel sheet for home electric appliances, building materials and automobile parts, cold rolled steel sheet having a plate thickness of 0.8 mm and a surface roughness Ra of 1.0 µm is coated with various zinc-based plating or aluminum-based plating. The plated steel sheet shown in Table 1 was used as a treated original plate, and after the surface of this plated steel sheet was alkali degreased and washed with water, it was subjected to chemical conversion treatment with the treatment liquid and treatment conditions shown in Table 2 to form a chemical conversion coating. Formed. Then, the coating composition shown in Table 3 was applied by a roll coater and dried by heating to form a second layer film (organic film), and the organic coated steel sheets of the examples of the present invention and the comparative examples were manufactured.
The film thickness of the second layer film is the solid content (heating residue) of the coating composition.
Alternatively, it was adjusted by the coating conditions (roll rolling force, rotation speed, etc.).

The obtained organic coated steel sheet was evaluated for quality performance (film appearance, white rust resistance, white rust resistance after alkali degreasing, paint adhesion, workability). The results are shown in Tables 7 and 2 together with the chemical conversion coating and the coating composition of the organic coating.
2 shows. The quality performance of the organic coated steel sheet was evaluated as follows.

(1) Appearance of coating film Each sample was visually evaluated for uniformity of appearance of coating film (with or without unevenness). The evaluation criteria are as follows. ◯: Uniform appearance with no unevenness Δ: Appearance with some conspicuous unevenness ×: Appearance with conspicuous unevenness

(2) White rust resistance For each sample, salt spray test (JIS-Z-23
71) was carried out and the white rust generation area ratio after a predetermined time was evaluated. The evaluation criteria are as follows. ◎: White rust does not occur ○ +: White rust occurrence area ratio is less than 5% ○: White rust occurrence area ratio is 5% or more and less than 10% ○-: White rust occurrence area ratio is 10% or more and less than 25% △: White rust Occurrence area ratio 25% or more and less than 50% ×: White rust occurrence area ratio 50% or more

(3) White rust resistance after alkaline degreasing For each sample, alkaline treatment liquid CLN-364S (60 ° C., spray 2 manufactured by Nippon Parkerizing Co., Ltd.)
After degreasing with alkali, the salt spray test (JIS
-Z-2371) was carried out, and the white rust area ratio after a predetermined time was evaluated. ◎: White rust does not occur ○ +: White rust occurrence area ratio is less than 5% ○: White rust occurrence area ratio is 5% or more and less than 10% ○-: White rust occurrence area ratio is 10% or more and less than 25% △: White rust Occurrence area ratio 25% or more and less than 50% ×: White rust occurrence area ratio 50% or more

(4) Paint adhesion For each sample, a melamine-based baking paint (film thickness 30
(μm), then soak it in boiling water for 2 hours, immediately cut a grid (10 × 10 grid at 1 mm intervals), apply and peel with an adhesive tape, and remove the coating film. The rate was evaluated. The evaluation criteria are as follows. ◎: No peeling ○: Peeling area ratio less than 5% △: Peeling area ratio 5% or more, less than 20% ×: Peeling area ratio 20% or more

(5) Workability Deep drawing was carried out with a blank diameter of 120 mm and a die diameter of 50 mm (oil-free condition), and the molding height until cracking was evaluated. The evaluation criteria are as follows. ◎: Through-drawing ○: Molding height of 30 mm or more △: Molding height of 20 mm or more, less than 30 mm ×: Molding height of less than 20 mm

[0117]

[Table 1]

[0118]

[Table 2]

[0119]

[Table 3]

[0120]

[Table 4]

[0121]

[Table 5]

[0122]

[Table 6]

[0123]

[Table 7]

[0124]

[Table 8]

[0125]

[Table 9]

[0126]

[Table 10]

[0127]

[Table 11]

[0128]

[Table 12]

[0129]

[Table 13]

[0130]

[Table 14]

[0131]

[Table 15]

[0132]

[Table 16]

[0133]

[Table 17]

[0134]

[Table 18]

[0135]

[Table 19]

[0136]

[Table 20]

[0137]

[Table 21]

[0138]

[Table 22]

[Example 2] In order to obtain an organic coated steel sheet for home appliances, building materials and automobile parts, cold rolled steel sheet having a plate thickness of 0.8 mm and a surface roughness Ra of 1.0 µm is coated with various zinc-based plating or aluminum-based plating. The plated steel sheet shown in Table 1 is used as a treatment original plate, and the surface of this plated steel sheet is subjected to alkaline degreasing treatment, water washing and drying, and then one of the following coating-type chromate treatment, electrolytic-type chromate treatment, and reactive-type chromate treatment Chromate treatment was performed to form a chromate film. Then, the coating composition shown in Table 3 is applied by a roll coater and dried by heating to form a second layer film (organic film).
Was formed, and the organic coated steel sheets of the present invention example and the comparative example were manufactured. The film thickness of the second layer coating was adjusted by the solid content (residual residue) of the coating composition or the coating conditions (roll rolling force, rotation speed, etc.).

Reactive chromate-treated chromic anhydride: 30 g / l, phosphoric acid: 10 g / l, Na
Using a treatment solution containing F: 0.5 g / l and K ₂ TiF ₆ : 4 g / l, spray treatment was carried out at a bath temperature of 40 ° C., followed by washing with water and drying. The chromium deposition amount was adjusted by changing the treatment time and the free acidity.

Electrolytic Chromate Treatment Chromic anhydride: 30 g / l, sulfuric acid: 0.2 g / l, a cathodic electrolysis treatment was carried out using a treatment liquid having a bath temperature of 40 ° C., followed by washing with water and drying. The amount of chromium deposited was adjusted by controlling the amount of electricity applied during electrolysis.

Coating-type chromate treatment (a) Chromic anhydride aqueous solution: A reducing agent (starch) was added to 100 g / l, the temperature was adjusted to 80 ° C., and the mixture was allowed to stand for 2 hours to reduce a part of chromic anhydride. An aqueous solution of hexavalent Cr / 3 trivalent Cr: 3/2 was prepared. Next, silica sol was added to this aqueous solution so that the ratio of silica / total Cr: 6/1 was obtained, and a zinc phosphate aqueous solution obtained by dissolving zinc oxide and phosphoric acid was added to PO ₄ ions / total Cr: The chromate treatment liquid was adjusted by adding 1/4, divalent Zn / 6 hexavalent Cr: 3/20. This chromate treatment solution was diluted to a predetermined concentration, coated on the surface of various plated steel sheets with a roll coater, and heated and dried at a plate temperature of 70 to 250 ° C. without washing with water. The amount of chromium deposited was adjusted by changing the concentration of the treatment liquid and the coating conditions.

Coating-type chromate treatment (b) Chromic anhydride aqueous solution: 20 g / l (1 L), a reducing agent (saturated aqueous oxalic acid solution: 1 L) and phosphoric acid: 100 ml were gradually added, and the mixture was allowed to stand at room temperature for 24 hours and then dried. Chromic acid was reduced to prepare a chromate treatment liquid having hexavalent Cr / total Cr <0.1 and pH = 1. This chromate treatment solution was diluted to a predetermined concentration, coated on the surface of various plated steel sheets with a roll coater, and heated and dried at a plate temperature of 70 to 250 ° C. without washing with water. The amount of chromium deposited was adjusted by changing the concentration of the treatment liquid and the coating conditions.

The obtained organic coated steel sheet was evaluated for quality performance (chromium elution resistance, white rust resistance, white rust resistance after alkaline degreasing, paint adhesion, workability). The results are shown in Tables 23 to 50 together with the film constitutions of the chromate-treated film and the organic film. The quality performance of the organic coated steel sheet was evaluated as follows.

(1) Chromium elution resistance (chromium fixing rate) Each sample was subjected to degreasing treatment under standard conditions with the degreasing agent PALCLEAN N364S manufactured by Nippon Parkerizing Co., Ltd., and the chromium fixing rate before and after degreasing was measured. did.
In addition, chromium fixing rate = {(amount of chromium deposited before degreasing-amount of chromium deposited after degreasing) / amount of chromium deposited before degreasing} × 100
(%). The evaluation criteria are as follows. ◎: Chromium fixing rate 100% ○: Chromium fixing rate 90% or more, less than 100% △: Chromium fixing rate 80% or more, less than 90% ×: Chromium fixing rate less than 80%

(2) White rust resistance Same as Example 1 (3) White rust resistance after alkaline degreasing Same as Example 1 (4) Paint adhesion Same as Example 1 (5) Workability Same as Example 1

[0147]

[Table 23]

[0148]

[Table 24]

[0149]

[Table 25]

[0150]

[Table 26]

[0151]

[Table 27]

[0152]

[Table 28]

[0153]

[Table 29]

[0154]

[Table 30]

[0155]

[Table 31]

[0156]

[Table 32]

[0157]

[Table 33]

[0158]

[Table 34]

[0159]

[Table 35]

[0160]

[Table 36]

[0161]

[Table 37]

[0162]

[Table 38]

[0163]

[Table 39]

[0164]

[Table 40]

[0165]

[Table 41]

[0166]

[Table 42]

[0167]

[Table 43]

[0168]

[Table 44]

[0169]

[Table 45]

[0170]

[Table 46]

[0171]

[Table 47]

[0172]

[Table 48]

[0173]

[Table 49]

[0174]

[Table 50]

As a conventional reaction-type chromate-treated steel sheet,
Chromic anhydride: 30 g / l, phosphoric acid: 10 g / l, Na
F: 0.5 g / l, K ₂ TiF ₆ : 4 g / l was used, and the amount of chromium deposited (calculated as metallic chromium) was obtained by spraying at a bath temperature of 40 ° C. and then washing and drying. Of 20 mg / m ² of chromate-treated steel sheet was manufactured. When this was subjected to a salt spray test under the same conditions as in this example, white rust occurred in about 24 hours. Therefore,
From this result and the result of this example, it is understood that the organic coated steel sheet of the present invention can obtain much more excellent corrosion resistance than the conventional chromate-treated steel sheet.

[0176]

As described above, the organic coated steel sheet of the present invention is chromated even when a chemical conversion treatment film containing no hexavalent chromium (for example, a phosphate treatment film) is used as the underlying chemical conversion treatment film. It has excellent corrosion resistance comparable to that of the coating, and when a chromate coating is used as the chemical conversion coating, it has significantly better corrosion resistance than conventional chromate treated steel sheets, but also excellent chromium elution resistance. Sex is obtained. Therefore, the organic coated steel sheet of the present invention has high utility as an environment-adaptive surface-treated steel sheet for applications such as building materials, home appliances, and automobiles.

Continuation of front page (51) Int.Cl. ⁷ Identification code FI C23C 22/50 C23C 22/50 28/00 28/00 C (72) Inventor Satoshi Ando 1-1-2 Marunouchi, Chiyoda-ku, Tokyo Nippon Steel Pipe Incorporated (72) Inventor Masaaki Yamashita 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Inside Nihon Kokan Co., Ltd. (56) Reference JP-A-7-278844 (JP, A) JP-A-10-264307 (JP , A) JP-A-9-94916 (JP, A) JP-B-62-24505 (JP, B1) (58) Fields investigated (Int.Cl. ⁷ , DB name) C23C 22/00-22/86 B05D 7/24 C23C 2/06 C23C 28/00

Claims (8)

(57) [Claims] 1. A zinc-based plated steel sheet or an aluminum-based plated steel sheet having a chemical conversion treatment film on the surface thereof,
A reaction product of the film-forming organic resin (A) with an active hydrogen-containing compound (B) consisting of a hydrazine derivative (C) in which some or all of the compounds have active hydrogen, zinc phosphate and / or aluminum phosphate ( a) and the content of the zinc phosphate and / or the aluminum phosphate (a) is 1 with respect to 100 parts by weight (solid content) of the reaction product.
~ 100 parts by weight (solid content), film thickness 0.1 ~ 5μ
An organic coated steel sheet having excellent corrosion resistance, which is characterized by having an organic film of m. 2. A zinc-based plated steel sheet or an aluminum-based plated steel sheet having a chemical conversion treatment film on the surface thereof,
A reaction product of the film-forming organic resin (A) with an active hydrogen-containing compound (B) consisting of a hydrazine derivative (C) in which some or all of the compounds have active hydrogen, zinc phosphate and / or aluminum phosphate ( a) and a calcium compound (b), wherein the zinc phosphate and / or aluminum phosphate (a) and the calcium compound (b) are included.
Is 1 to 100 parts by weight (solid content) with respect to 100 parts by weight (solid content) of the reaction product, and zinc phosphate and / or aluminum phosphate (a) and calcium compound (b). ) Content (solid content) weight ratio (a) / (b) is 1/99 to 99/1, and is excellent in corrosion resistance, characterized by having an organic film with a film thickness of 0.1 to 5 μm Organic coated steel sheet. 3. A zinc-based plated steel sheet or an aluminum-based plated steel sheet has a chemical conversion treatment film on the surface thereof,
A reaction product of the film-forming organic resin (A) with an active hydrogen-containing compound (B) consisting of a hydrazine derivative (C) in which some or all of the compounds have active hydrogen, zinc phosphate and / or aluminum phosphate ( a) and a solid lubricant (c), and the content of the zinc phosphate and / or the aluminum phosphate (a) is 1 to 100 parts by weight with respect to 100 parts by weight (solid content) of the reaction product. (Solid content),
If the content of the solid lubricant (c) is the reaction product 100,
An organic coated steel sheet having excellent corrosion resistance, which has an organic coating having a film thickness of 0.1 to 5 μm, which is 1 to 80 parts by weight (solid content) with respect to parts by weight (solid content). 4. A zinc-based plated steel sheet or an aluminum-based plated steel sheet has a chemical conversion treatment film on the surface thereof,
A reaction product of the film-forming organic resin (A) with an active hydrogen-containing compound (B) consisting of a hydrazine derivative (C) in which some or all of the compounds have active hydrogen, zinc phosphate and / or aluminum phosphate ( a), a calcium compound (b), and a solid lubricant (c), and the total content of the zinc phosphate and / or aluminum phosphate (a) and the calcium compound (b) is the reaction product. 1 to 100 parts by weight (solid content) with respect to 100 parts by weight (solid content), and the content (solid content) of zinc phosphate and / or aluminum phosphate (a) and calcium compound (b). Weight ratio (a) / (b) is 1/99 to 99 /
1, the content of the solid lubricant (c) is 1 to 80 parts by weight (solid content) with respect to 100 parts by weight (solid content) of the reaction product, and the film thickness is 0.1 to 5 μm. An organic coated steel sheet with excellent corrosion resistance, characterized by having an organic coating. 5. The film-forming organic resin (A) is an epoxy group-containing resin (D), 1.
Alternatively, the organic coated steel sheet having excellent corrosion resistance as described in 4 above. 6. The hydrazine derivative (C) having active hydrogen is a pyrazole compound having active hydrogen and / or
Alternatively, it is a triazole compound having active hydrogen, and the organic coated steel sheet having excellent corrosion resistance according to claim 1, 2, 3, 4 or 5. 7. The hydrazine derivative (C) having active hydrogen is contained in the active hydrogen-containing compound (B) in an amount of 10 to 100 mol%, 1.
The organic coated steel sheet having excellent corrosion resistance according to 5 or 6. 8. The organic coated steel sheet having excellent corrosion resistance according to claim 5, 6 or 7, wherein the epoxy group-containing resin (D) is an epoxy resin represented by the following formula (1). [Chemical 1]