JP5036924B2 - Water-based coating composition, coated metal molded article, and method for producing coated metal molded article - Google Patents

Description

The present invention relates to an aqueous coating composition, a coated metal molded article, and a method for producing a coated metal molded article.
In particular, it can be used as an alternative technology to chrome plating, and can produce water-based coating compositions, coated metal molded products, and coated metal molded products that can stably form a coating film with excellent adhesion to the substrate. Regarding the method.

Conventionally, adhesion, durability, smoothness, rust prevention, etc. have been applied to coatings for automobile headrest stays, golf club shafts, umbrella frames, automobile parts, steel furniture, home appliance housings, bolts, nuts, etc. For this reason, chrome plating is used.
However, such chrome plating sometimes contains hexavalent chromium having biotoxicity and carcinogenicity, and there has been a problem that it easily causes environmental pollution such as groundwater contamination.

Therefore, various coating techniques that are alternatives to chromium plating have been proposed.
For example, in a nickel-tungsten alloy plating film, a heat-resistant hard nickel-tungsten alloy plating film is disclosed, in which fine titanium metal particles and fine silicon carbide particles are uniformly dispersed in the plating film. (For example, refer to Patent Document 1).

  (B) contains gluconate, (b) contains nickel salt, (c) contains molybdate, (d) does not substantially contain iron ions, (e) organic amines Has been disclosed (see, for example, Patent Document 2).

In addition, an anticorrosive coating composition containing the following (a) and (b) as essential components is applied to the surface of an iron material whose surface is coated with a primer mainly composed of at least one metal selected from zinc and aluminum. And the manufacturing method of the corrosion-resistant iron material hardened by room temperature processing or heat processing is disclosed (for example, refer patent document 3).
(A) a compound having at least one phenolic hydroxyl group in the molecule (b) a compound having at least one siloxane bond selected from the group of predetermined silicates and predetermined silicates and / or their Condensate

In addition, a porous coating layer of zinc or zinc-iron alloy formed on the surface of the iron material, and a composite coating layer of polysiloxane and thermosetting resin formed by being laminated on the porous coating layer were provided. Steel materials are disclosed (see, for example, Patent Document 4).
And as thermosetting resin which can be used, thermosetting polyester, the phenol resin which has an effect as a rust preventive agent, etc. are mentioned.

Furthermore, a rust preventive coating composition containing the following (A ') and (B') as an essential component is applied to the surface of an iron material coated with an undercoat composed mainly of at least one selected from zinc and aluminum. Then, a method for producing a corrosion-resistant iron material is proposed which is cured by room temperature treatment or heat treatment, further coated with a top coating composition containing the following (c) as an essential component as a protective layer, and cured by room temperature treatment or heat treatment. (For example, refer to Patent Document 5).
(B) a compound having at least one phenolic hydroxyl group in the molecule (b) a predetermined silane compound alone, a mixture of two or more kinds, a condensable product of two or more kinds of mixtures, or a mixture thereof (c) ′) Predetermined silicates, predetermined silicates, mixtures thereof, or condensation products thereof

Japanese Patent Laid-Open No. 7-197297 (Claims) Japanese Patent Laying-Open No. 2005-82856 (Claims) JP 2003-328151 A (Claims) JP 2002-292792 (Claims) JP-A-2004-197151 (Claims)

However, since the coating techniques disclosed in Patent Documents 1 and 2 each use an electroplating technique, there has been a problem that process management in manufacturing a coated metal molded product is complicated.
That is, in order to form a uniform coating film on the coated metal molded product, it is necessary to strictly control the size of the plating tank, the control of the supply current, and the like.
Furthermore, since a considerable amount of time is required to obtain a desired film thickness, there has been a problem that not only the production cost of the coated metal molded product is increased, but also the production yield is low.

In addition, the coating techniques disclosed in Patent Documents 3 to 5 require that an undercoat layer made of zinc or aluminum is provided by thermal spraying or the like for each iron material to be coated, so that the manufacturing cost is high. Above all, there was a problem that the manufacturing yield was low.
In addition, when an undercoat layer made of zinc or aluminum is omitted and a coating film is formed directly on the iron material, there is a problem that the rust prevention property is excessively lowered.

As a result of intensive studies, the present inventors have found that (a) a silicone compound, (b) an organic resin component having a predetermined hydroxyl value, (c) a phenolic hydroxyl group-containing compound, (d) a crosslinking agent, and (e) It has been found that a water-based coating composition containing a water-based solvent at a predetermined ratio can provide a coating film excellent in adhesion to a base (metal molded product), and the present invention has been completed.
That is, the object of the present invention can be used as an alternative technique for chromium plating, and even when an undercoat layer (zinc-containing porous coating layer, etc.) made of zinc or aluminum is omitted, adhesion to the substrate, etc. It is an object of the present invention to provide a water-based coating composition capable of stably forming a coating film excellent in, a coated metal molded article using the same, and a method for producing a coated metal molded article.

According to the present invention, an aqueous coating composition comprising the following components (a) to (e), wherein the silicone compound as component (a) is composed of tetraalkoxysilane, alkyltrialkoxysilane and dialkyldialkoxysilane. It is at least one selected from the group consisting of a methyl group, an ethyl group, a propyl group or a butyl group in the case of an alkyl group, and a methoxy group, an ethoxy group or a propoxy group in the case of an alkoxy group. The water-based coating composition characterized by the above is provided, and the above-mentioned problems can be solved.
(A) Silicone compound 100 parts by weight (b) Organic resin component having a hydroxyl value in the range of 1 to 500 mgKOH / g
15 to 200 parts by weight (c) phenolic hydroxyl group-containing compound 0.1 to 30 parts by weight (d) (b) component crosslinking agent 0.05 to 5 parts by weight (e) aqueous solvent 100 to 2000 parts by weight

That is, as the component (b), an organic resin component having a predetermined hydroxyl value (hereinafter sometimes simply referred to as an organic resin component) is used. A water-based coating composition having a good compatibility and a uniform composition can be formed. As a result, a coating film excellent in adhesion and smoothness can be stably applied to a metal molded article or the like. Can be formed.
Moreover, since a phenolic hydroxyl group-containing compound is contained at a predetermined ratio, it is possible to exhibit excellent rust prevention properties for metal molded articles and the like by a predetermined reducing action without using harmful chromium compounds. .
In addition, when the coating film is formed, the silicone compound and the organic resin component having a predetermined hydroxyl value are microphase-separated in the coating film, respectively, and the organic resin component is applied to the coating side of the metal molded product or the like. As a result of the electron microanalyzer (EPMA) elemental analysis, it has been found that the silicone compound is unevenly distributed on the surface of the coating film opposite to the metal molded product. It is a factor that improves the properties and rust prevention properties.
Therefore, even when an undercoat layer made of zinc or aluminum is omitted, a coating film excellent in adhesion and durability can be easily and stably formed, and thus excellent rust prevention is obtained. be able to.

In constituting the water-based coating composition of the present invention, it is preferable that the organic resin component as the component (b) is a polyester resin or a phenoxy resin.
By comprising in this way, adjustment of the hydroxyl value in resin becomes easy, and when apply | coated to a metal molded article etc., a silicone compound and the organic resin component which has a predetermined hydroxyl value in a coating film Microphase separation (uneven distribution) can be achieved more effectively, and the adhesion to a metal molded product or the like can be improved more effectively.

In constituting the water-based coating composition of the present invention, the component (c) is preferably a tannic acid compound.
By comprising in this way, not only rust prevention property can be improved, but the convergence property at the time of drying an aqueous coating-coating composition can be improved.

In constituting the water-based coating composition of the present invention, the component (d) is preferably at least one of an epoxy compound, an isocyanate compound, an aziridine compound and an organometallic compound.
By comprising in this way, (b) component can be hardened more rapidly and reliably.

Further, in constituting the aqueous coating paint composition of the present invention, as a component (f), a silane coupling agent is further included, and the blending amount thereof is 100 parts by weight of the silicone compound as the component (a). It is preferable to set it as the value within the range of 0.1-30 weight part.
By configuring in this way, when applied to a metal molded product, etc., it exerts an anchor effect between the silicone compound that is present in the coating film and the metal molded product, and adheres to the metal molded product Can be further effectively improved.

Further, in constituting the aqueous coating paint composition of the present invention, the component (g) further contains a lubricant, and the blending amount thereof is 0.5 parts by weight based on 100 parts by weight of the silicone compound as the component (a). A value within the range of ˜30 parts by weight is preferred.
By comprising in this way, predetermined | prescribed lubricity can be provided to the surface of a coating film.

Another embodiment of the present invention is an aqueous coating composition comprising the following components (a) to (e) on the surface of a metal molded article, wherein the silicone compound as the component (a) is a tetraalkoxy At least one selected from the group consisting of silane, alkyltrialkoxysilane and dialkyldialkoxysilane (however, in the case of an alkyl group, it is a methyl group, an ethyl group, a propyl group or a butyl group, and in the case of an alkoxy group, it is a methoxy group, ethoxy group) A coated metal molded article formed with a coating film formed by curing an aqueous coating composition .
(A) Silicone compound 100 parts by weight (b) Organic resin component having a hydroxyl value in the range of 1 to 500 mgKOH / g
15 to 200 parts by weight (c) phenolic hydroxyl group-containing compound 0.1 to 30 parts by weight (d) (b) component crosslinking agent 0.05 to 5 parts by weight (e) aqueous solvent 100 to 2000 parts by weight According to the coated metal molded product of the invention, it is possible to provide a headrest or the like provided with a coating film having excellent adhesion, durability, smoothness, rust prevention properties and the like.

Still another embodiment of the present invention is a method for producing a coated metal molded article, which comprises the following steps (1) to (3) in order.
(1) Step of preparing a metal molded product (2) An aqueous coating composition containing the following components (a) to (e) for the metal molded product, wherein the silicone compound as component (a) is tetra At least one selected from the group consisting of alkoxysilanes, alkyltrialkoxysilanes and dialkyldialkoxysilanes (provided that alkyl groups are methyl, ethyl, propyl, or butyl groups, and alkoxy groups are methoxy groups, A step of applying an aqueous coating coating composition which is an ethoxy group or a propoxy group ) (3) a step of curing the aqueous coating coating and forming a coating film (a) 100 parts by weight of a silicone compound (b) a hydroxyl value Organic resin component having a value within the range of 1 to 500 mgKOH / g
15 to 200 parts by weight (c) phenolic hydroxyl group-containing compound 0.1 to 30 parts by weight (d) (b) component crosslinking agent 0.05 to 5 parts by weight (e) aqueous solvent 100 to 2000 parts by weight According to the method for producing a coated metal molded product of the invention, it is possible to efficiently and stably produce a coated metal molded product having a coating film having excellent adhesion, durability, smoothness and rust prevention. it can.

FIG. 1 is a diagram showing the influence of the blending amount of an organic resin component having a predetermined hydroxyl value on the time until the occurrence of rust in the SST test. FIG. 2 is a diagram for explaining a headrest stay, a headrest, and the like. FIG. 3 is a diagram provided for explaining an application process of the aqueous coating paint composition. FIG. 4 is a diagram provided for explaining an application apparatus for an aqueous coating paint composition. FIG. 5 is an EPMA chart (carbon (C) distribution state) in the first embodiment. FIG. 6 is an EPMA chart (carbon (C) distribution state) in Example 3. FIG. 7 is an EPMA chart (carbon (C) distribution state) in Example 4. FIG. 8 is an EPMA chart (carbon (C) distribution status) in Example 10. FIG. 9 is an EPMA chart (carbon (C) distribution status) in Example 12. FIGS. 10A to 10C are diagrams provided to show the results of the SST test of the steel plate in Example 19. FIG.

[First Embodiment]
The first embodiment is an aqueous coating composition containing the following components (a) to (e), wherein the silicone compound as component (a) is a tetraalkoxysilane, an alkyltrialkoxysilane, and a dialkyldialkoxysilane An aqueous solution that is at least one selected from the group consisting of (in the case of an alkyl group, it is a methyl group, an ethyl group, a propyl group or a butyl group, and in the case of an alkoxy group, it is a methoxy group, an ethoxy group or a propoxy group). It is a coating paint composition.
(A) Silicone compound 100 parts by weight (b) Organic resin component having a hydroxyl value in the range of 1 to 500 mgKOH / g
15 to 200 parts by weight (c) phenolic hydroxyl group-containing compound 0.1 to 30 parts by weight (d) (b) component crosslinking agent 0.05 to 5 parts by weight (e) aqueous solvent 100 to 2000 parts by weight The water-based coating composition of the first embodiment will be specifically described with reference to the above as appropriate.

1. Silicone Compound The aqueous coating paint composition contains a predetermined amount of a silicone compound as the component (a).
This is because the silicone compound and the organic resin component having a predetermined hydroxyl value are contained in the coating film when the aqueous coating composition is applied to a metal molded article or the like by including a predetermined amount of the silicone compound. This is because it can be cured while being localized, and the adhesion to a metal molded product can be effectively improved.
That is, a rich layer of an organic resin component is formed on the inner surface side of the coating film that is in direct contact with the metal molded article, and a rich layer of a silicone compound is formed on the surface side of the coating film. This is because, as a whole, excellent adhesion, water repellency, heat resistance and the like to the metal molded product can be obtained.

(1) Kind The silicone compound is at least one selected from the group consisting of tetraalkoxysilane, alkyltrialkoxysilane and dialkyldialkoxysilane (however, in the case of an alkyl group, it is a methyl group, an ethyl group, a propyl group or a butyl group). In the case of an alkoxy group, it is a methoxy group, an ethoxy group or a propoxy group).

Among these, at least one selected from the group consisting of ethyl silicate, methyl silicate, and methyltrimethoxysilane is preferable.
The reason for this is that when these compounds are applied, the silicone compound and the organic resin component having a predetermined hydroxyl value are more effectively localized in the coating film when the aqueous coating composition is applied. This is because the adhesion to the metal molded product can be effectively improved.
In the case of a silicone compound, as mentioned above, it basically means a compound having a siloxane bond in the molecule, but it is a compound having no siloxane bond in the molecule, such as an alkoxysilane compound. However, any compound that can form a siloxane bond with each other by hydrolysis condensation is included in the silicone compound.

(2) Compounding quantity Moreover, it is preferable to make the compounding quantity of a silicone compound into the value within the range of 5-30 weight% with respect to the whole quantity (100 weight%) of an aqueous coating-coating composition.
The reason for this is that when the aqueous coating coating composition is applied, the silicone compound and the predetermined organic resin component are effectively localized in the coating film by setting the blending amount of such a silicone compound. This is because the adhesiveness to the metal molded product can be effectively improved while maintaining the predetermined water repellency and heat resistance.
That is, when the amount of the silicone compound is less than 5% by weight, the water repellency and water resistance are lowered, the effect of localization in the coating film becomes insufficient, and further, from the coating film This is because the phenolic hydroxyl group-containing compound may be easily eluted.
On the other hand, when the blending amount of the silicone compound exceeds 30% by weight, the localization in the coating film becomes insufficient, or the amount of the predetermined organic resin component relatively decreases, and the metal molded product is reduced. This is because the adhesion may be insufficient.
Therefore, the blending amount of the silicone compound is more preferably 8 to 25% by weight, more preferably 10 to 20% by weight, based on the total amount of the aqueous coating composition. More preferably.

2. Organic resin component (1) Hydroxyl value The aqueous coating composition contains an organic resin component having a hydroxyl value in the range of 1 to 500 mgKOH / g as component (b).
The reason for this is that by including such an organic resin component, the silicone compound and the organic resin component are cured while being more effectively localized in the coating film when applied to a metal molded article or the like. This is because the applicability to a metal molded product or the like and the adhesion of the coating film can be effectively improved.
In addition, since such an organic resin component can be easily dispersed in a silicone compound or a phenolic hydroxyl group-containing compound, the uniformity in the aqueous coating composition can be maintained over a long period of time. It is.
That is, when the value of the hydroxyl value is less than 1 mgKOH / g, the number of hydroxyl groups contributing to dispersibility becomes excessively small, making it difficult to uniformly disperse the silicone compound, or applying it to a metal molded product or the like. This is because the properties and adhesion may be excessively lowered.
On the other hand, when the hydroxyl value exceeds 500 mgKOH / g, the silicone compound and the organic resin component are sufficiently separated in the coating film when the aqueous coating composition is applied to a metal molded article or the like. This is because it becomes difficult to be present, and conversely, the applicability and adhesion to a metal molded product may be lowered.
Accordingly, the hydroxyl value in the organic resin component is more preferably set to a value within the range of 2 to 400 mgKOH / g, and further preferably set to a value within the range of 4 to 300 mgKOH / g.

In addition, it is also preferable to appropriately change the hydroxyl value of the organic resin component depending on the type of the organic resin component. For example, in the case of a polyester resin, the hydroxyl value is set to a value in the range of 4 to 20 mgKOH / g. Is more preferable, a value within the range of 5 to 15 mgKOH / g is more preferable, and a value within the range of 5.5 to 10 mgKOH / g is even more preferable.
Furthermore, when the organic resin component is a phenoxy resin, the hydroxyl value is preferably set to a value in the range of 200 to 300 mgKOH / g, more preferably set to a value in the range of 220 to 280 mgKOH / g. Preferably, the value is in the range of 250 to 270 mgKOH / g.

(2) Type The type of the organic resin component is not particularly limited. For example, polyester resin, urethane resin, phenoxy resin, epoxy resin, cellulose resin, phenol resin, acrylic resin, alkyd resin, poly An ether resin, a butyral resin, a ketone resin, and the like may be mentioned, but at least one selected from the group consisting of a polyester resin, a urethane resin, and a phenoxy resin is preferable.
The reason for this is that with these organic resin components, it is relatively easy to obtain a predetermined hydroxyl value, and in the aqueous coating composition (in a liquid state), between the silicone compound and the organic resin component. This is because good compatibility is obtained, and when applied, the silicone compound and the organic resin component can be cured while being more effectively localized in the coating film.

Of these organic resin components, polyester resins and phenoxy resins are particularly preferable.
The reason for this is that these organic resin components can be adjusted not only for the hydroxyl value but also for the acid value, and more excellent applicability and adhesion to metal molded products can be obtained. In addition, the silicone compound and the organic resin component can be cured while being more effectively localized in the coating film.

That is, if it is a polyester resin, it can be configured as a condensate of a polybasic acid and a polyhydric alcohol, but the polybasic acid and polyhydric alcohol, and further the type of the third component can be changed as appropriate. Thus, the hydroxyl value and the acid value can be appropriately adjusted to values within a predetermined range.
In addition, in the case of a polyester resin, while further excellent applicability and adhesion to a metal molded product and the like can be obtained, and compatibility with the silicone compound can be improved, the acid value is set to 0. A value within the range of 1 to 20 mg KOH / g is preferable.

On the other hand, a phenoxy resin is a polyhydroxy ether as a high molecular weight product of an epoxy compound, and can be obtained, for example, by polycondensation of bisphenols and epichlorohydrin in the presence of an alkali catalyst.
Therefore, the hydroxyl value and the acid value can be appropriately adjusted to values within a predetermined range by appropriately changing the types of the various bisphenols and epichlorohydrin and further the third component.
In addition, in the case of a phenoxy resin, while further excellent applicability and adhesion to a metal molded product and the like can be obtained, and compatibility with the silicone compound can be improved, the acid value thereof is 30 to 30. A value within the range of 60 mgKOH / g is preferred.

(3) Weight average molecular weight Moreover, it is preferable to make the weight average molecular weight of an organic resin component into the value within the range of 2,000-50,000.
The reason for this is that when the weight average molecular weight is less than 2,000, not only the durability tends to be excessively lowered, but also chemical resistance and handling properties are likely to be lowered.
On the other hand, when the weight average molecular weight exceeds 50,000, the uniformity of the aqueous coating composition is excessively decreased, the viscosity is excessively increased, or the coating composition is localized in the coating film. This is because there is a case where the amount becomes insufficient.
Therefore, the weight average molecular weight of the organic resin component is more preferably set to a value within the range of 5,000 to 40,000, and further preferably set to a value within the range of 8,000 to 30,000.
In addition, the weight average molecular weight of an organic resin component can be measured as polystyrene conversion molecular weight using GPC (gel permeation chromatography).

(4) Water dispersibility In addition, the predetermined organic resin component is preferably a water dispersible organic resin component.
The reason for this is that the water-dispersible organic resin component having water-dispersibility can be more uniformly dispersed with respect to the silicone compound and the phenolic hydroxyl group-containing compound. This is because a coating film excellent in smoothness can be formed more stably.
On the other hand, when an aqueous coating composition is applied to a metal molded article or the like to be coated, the silicone compound and the organic resin component having a predetermined hydroxyl value are more effective in the coating film. Therefore, it is possible to more effectively improve the adhesion to a metal molded product or the like.

The water dispersibility of the organic resin component means a state in which the organic resin component can be dissolved or dispersed in water or an aqueous solvent obtained by mixing an organic solvent mainly containing water.
Further, the state in which the organic resin component can be dispersed means a state generally referred to as an emulsion or a colloidal dispersion, and the average particle size of such an emulsion is usually in the range of 0.001 to 3 μm. It is preferable that it is a value within this, and it is more preferable that it is a value within the range of 0.04-1 micrometer.
Further, regarding the water dispersibility of the organic resin component, even when the organic resin component is dissolved in water at a concentration of 1% by weight and left at 25 ° C. for 24 hours, the organic resin component is precipitated or phase separated. It is possible to make a judgment based on whether or not the uniform state is maintained.

(5) Compounding quantity Moreover, it is characterized by making the compounding quantity (solid content conversion) of an organic resin component into the value within the range of 15-200 weight part with respect to 100 weight part of silicone compounds.
The reason for this is that when the amount of the organic resin component is less than 15 parts by weight, the absolute amount of the organic resin component is excessively reduced, and the effect of localization in the coating film becomes insufficient. This is because the adhesion of the coating film to a metal molded product or the like may be insufficient.
On the other hand, when the amount of the organic resin component exceeds 200 parts by weight, the amount of the organic resin component relative to the silicone compound becomes excessive, resulting in insufficient localization of these components in the coating film. This is because the adhesion to the metal molded product may be insufficient.
Therefore, the blending amount of the organic resin component is more preferably set to a value within the range of 20 to 120 parts by weight, and more preferably within a range of 30 to 80 parts by weight with respect to 100 parts by weight of the silicone compound. Further preferred.

Here, the relationship between the compounding quantity of the organic resin component which has a predetermined hydroxyl value, and rust prevention property is demonstrated using FIG.
That is, in FIG. 1, the horizontal axis represents the blending amount (parts by weight) of a polyester resin (hydroxyl number: 5.8) as an example of an organic resin component having a predetermined hydroxyl value with respect to 100 parts by weight of the silicone compound. On the vertical axis, a characteristic curve taking time (time) until rust generation in the SST test based on JISZ2371 is shown.

As understood from the characteristic curve, as the blending amount of the organic resin component increases, the time until rust generation in the SST test becomes longer.
More specifically, if the blending amount of the organic resin component is 15 parts by weight or more, the time until the occurrence of rust in the SST test can be set to a level of about 100 hours or more, and the blending amount of the organic resin component Is 50 parts by weight or more, the time until rust generation in the SST test can be set to a level of about 200 hours or more. If the amount of the organic resin component is 150 parts by weight or more, rust in the SST test is achieved. It can be seen that the time until occurrence can be set to a level of about 400 hours.
On the other hand, it has been separately confirmed that when the blending amount of the organic resin component having a predetermined hydroxyl value exceeds 200 parts by weight, problems such as deterioration in storage stability of the aqueous coating coating composition are likely to occur. ing.
Therefore, it is understood that the blending amount of the organic resin component having a predetermined hydroxyl value should be a value within the range of 15 to 200 parts by weight with respect to 100 parts by weight of the silicone compound.
It has been confirmed that similar results can be obtained even when a phenoxy resin is used as the organic resin component having a predetermined hydroxyl value.

3. Phenolic hydroxyl group-containing compound Moreover, the aqueous coating composition contains a phenolic hydroxyl group-containing compound as the component (c).
The reason for this is that by blending a predetermined amount of such a phenolic hydroxyl group-containing compound, the compound can function as a catalyst for the curing reaction of component (a) and exhibit an excellent function as an antirust agent. This is because it can.
That is, the phenolic hydroxyl group-containing compound reacts with iron to form an iron salt, forms a complex compound, and can reduce oxygen permeation.

(1) Kind Moreover, as a kind of this phenolic hydroxyl group containing compound, phenol, cresol, thymol, bromophenol, naphthol, anilinophenol etc. are mentioned as monovalent phenols, for example, Divalent phenols Pyrocatechin (catechol), resorcin, hydroquinone, orcin, urushiol, bisphenol A, binaphthol and the like. Examples of trivalent phenols include pyrogallol, phloroglucin, hydroxyhydroquinone, 3,4,5-trihydroxybenzenecarboxyl. Acid (gallic acid), 3,4,5-trihydroxybenzenecarboxylic acid ester, etc., and polyhydric phenols such as tannic acid compounds (tannic acid, vanadium tannate, molybdenum tannate, aluminum tannate) And tannic acid tungsten) and phenol-formaldehyde condensates (phenolic resins).

Further, among these phenolic hydroxyl group-containing compounds, in particular, from the group consisting of vanadium tannate, molybdenum tannate, 3,4,5-trihydroxybenzenecarboxylic acid and 3,4,5-trihydroxybenzenecarboxylic acid ester. It is preferable to include at least one selected.
This is because these phenolic hydroxyl group-containing compounds can form a rust-proof coating effectively by chelating reaction with the steel material surface.
In addition, tannic acid salts such as tannic acid and vanadium tannate are effective as a black colorant for the coating film in addition to the effect as a rust preventive agent when the metal molded product to be coated is a steel material. It is particularly useful in that it also has.
In addition, a phenol-formaldehyde condensate (phenol resin) or the like is particularly useful in that the film-forming property of the coating film can be further improved because of self-condensation.

(2) Compounding quantity Moreover, it is characterized by making the compounding quantity of a phenolic hydroxyl-containing compound into the value within the range of 0.1-30 weight part with respect to 100 weight part of silicone compounds.
This is because the balance between rust prevention and water resistance in the coating film can be effectively improved by setting the blending amount of the phenolic hydroxyl group-containing compound to a value within a predetermined range. .
That is, when the blending amount of the phenolic hydroxyl group-containing compound is less than 0.1 parts by weight, it may be difficult to obtain a sufficient effect as a rust inhibitor by the phenolic hydroxyl group-containing compound. .
On the other hand, when the blending amount of the phenolic hydroxyl group-containing compound exceeds 30 parts by weight, the phenolic hydroxyl group-containing compound tends to be excessively eluted, and it may be difficult to obtain sufficient water resistance. Because.
Therefore, the blending amount of the phenolic hydroxyl group-containing compound is more preferably set to a value within the range of 0.5 to 15 parts by weight with respect to 100 parts by weight of the silicone compound, and a value within the range of 1 to 2 parts by weight. More preferably.

4). Crosslinking agent (1) type Moreover, the aqueous coating-coating composition contains the crosslinking agent of the organic resin component as (b) component as (d) component.
The reason for this is that by including such a crosslinking agent, the component (b) can be cured to form a strong coating film, and excellent water resistance and durability, and excellent rust prevention properties resulting therefrom can be obtained. Because it can.

Moreover, the kind of this crosslinking agent can be suitably selected according to the kind of (b) component, For example, an epoxy compound, an isocyanate compound, block isocyanate, an aziridine compound, an organometallic compound, etc. can be mentioned.
Therefore, when the organic resin component as the component (b) includes, for example, a polyester resin, it is preferable to use an organic titanium compound and / or an organic zirconium compound as a crosslinking agent.
The reason for this is that if the organic titanium-based compound and the organic zirconium-based compound are combined with the resin characteristics of the polyester resin, the water-based coating composition is cured while being more uniformly combined, resulting in better water resistance and durability. This is because, as a result, excellent rust prevention can be obtained more stably.
That is, considering only the reaction rate, it is preferable to use an isocyanate compound having excellent reactivity with a hydroxyl group, but when an aqueous solvent is contained in a large amount, an isocyanate compound having high reactivity with water, The crosslinkability of the polyester resin may be insufficient.
Therefore, an organic titanium compound and an organic zirconium compound that have relatively low reactivity with water can avoid such a problem and effectively crosslink the polyester resin, and can also provide a predetermined catalyst. Depending on the function, silicone compounds, phenol-formaldehyde condensates and the like can be effectively condensed.

Here, examples of the organic titanium compound include titanium tetraisopropoxide, titanium tetranormal butoxide, titanium butoxide dimer, titanium tetra-2-ethylhexoxide, titanium diisopropoxybis (acetylacetonate), and titanium tetra. (Acetylacetonate), titanium dioctyloxybis (octylene glycolate), titanium diisopropoxybis (ethyl acetoacetate), titanium diisopropoxybis (triethanolaminate), titanium lactate ammonium salt, titanium lactate, poly Examples thereof include hydroxy titanium stearate, di-n-butoxy titanium bis (triethanolaminate), polytitanium bis (acetylacetonate) and the like.
Examples of organic zirconium compounds include zirconium tetranormal propoxide, zirconium tetranormal butoxide, zirconium tetraacetylacetonate, zirconium tributoxymonoacetylacetonate, zirconium monobutoxyacetylacetonate, zirconium butoxybis (ethylacetoacetate). ), Zirconium tetraacetylacetonate, zirconium tributoxy monostearate, zirconium chloride compound aminocarboxylic acid and the like.

Moreover, when the organic resin component as (b) component contains a phenoxy resin, it is preferable to use a blocked isocyanate as a crosslinking agent.
The reason for this is that if it is a blocked isocyanate, the phenoxy resin can be cured more uniformly to obtain better water resistance and durability, and in turn, excellent rust resistance can be obtained more stably. It is.
That is, if it is a blocked isocyanate, it is easy to react with the secondary hydroxyl group of the phenoxy resin, and when the hydroxyl group concentration is high, the crosslinking density becomes high and the coating film properties after crosslinking can be improved. It is.

(2) Compounding quantity Moreover, it is characterized by making the compounding quantity of a crosslinking agent into the value within the range of 0.05-5 weight part with respect to 100 weight part of silicone compounds.
This is because when the amount of the crosslinking agent is less than 0.05 parts by weight, it may be difficult to sufficiently exert the crosslinking function and the catalytic function of the crosslinking agent.
On the other hand, when the amount of the crosslinking agent exceeds 5 parts by weight, it may be difficult to mix uniformly in the aqueous coating composition, or the coating film may be excessively shrunk. Because there is.
Therefore, the blending amount of the crosslinking agent is more preferably set to a value in the range of 0.1 to 2 parts by weight with respect to 100 parts by weight of the silicone compound, and a value in the range of 0.5 to 1 part by weight More preferably.

5. Type of aqueous solvent (1) The aqueous coating paint composition is characterized by containing a predetermined amount of an aqueous solvent as the component (e). Examples of the aqueous solvent include water, alcohol, and a water / alcohol mixture. Etc.
It is also preferable to add a diluting solvent such as ketones and glycols as part of the aqueous solvent in order to adjust the viscosity during handling.
Furthermore, in order to improve the compatibility between the silicone compound and the organic resin component, it is also preferable to add a surfactant or a compatibilizing agent as a part of the aqueous solvent.
In addition, this aqueous solvent should just be finally mix | blended with predetermined amount in an aqueous coating-coating composition, and mix | blends a part of aqueous solvent as dispersion media, such as (a) component-(d) component. Is also preferable.

(2) Compounding quantity Moreover, the compounding quantity of an aqueous solvent is made into the value within the range of 100-2000 weight part with respect to 100 weight part of silicone compounds, It is characterized by the above-mentioned.
This is because when the amount of the aqueous solvent is less than 100 parts by weight, the viscosity of the aqueous coating composition may increase excessively and the applicability and storage stability may decrease.
On the other hand, when the amount of the aqueous solvent exceeds 2000 parts by weight, the viscosity of the aqueous coating composition may be excessively lowered, the handling property may be lowered, or a coating film having a predetermined thickness may be formed. This is because it may be difficult.
Therefore, it is more preferable to set the blending amount of the aqueous solvent to a value within the range of 300 to 1200 parts by weight and further to a value within the range of 500 to 800 parts by weight with respect to 100 parts by weight of the silicone compound. preferable.

6). Silane coupling agent (1) type Moreover, it is preferable that an aqueous coating-coating composition contains a silane coupling agent further as (f) component.
This is because the adhesiveness to the substrate can be further improved by blending a predetermined amount of such a silane coupling agent.
The types of such silane coupling agents include vinyltrimethoxysilane, vinyltriethoxysilane, methacryloxypropyltrimethoxysilane, methacryloxypropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycol. Sidoxypropyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- ( 2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane and the like may be used alone or in combination of two or more.

(2) Compounding quantity Moreover, it is preferable to make the compounding quantity of the silane coupling agent as a (f) component into the value within the range of 0.1-30 weight part with respect to 100 weight part of silicone compounds.
This is because when the amount of the silane coupling agent is less than 0.1 parts by weight, it may be difficult to obtain sufficient effects such as improvement in lubricity, rust prevention and water resistance. Because.
On the other hand, when the blending amount of the silane coupling agent exceeds 30 parts by weight, it may be difficult to blend uniformly in the aqueous coating composition.
Therefore, the blending amount of the silane coupling agent is more preferably set to a value in the range of 0.3 to 25 parts by weight with respect to 100 parts by weight of the silicone compound, and a value in the range of 2 to 20 parts by weight More preferably.

7). Type of lubricant (1) It is preferable that the water-based coating composition further contains a lubricant as the component (g).
The reason for this is that by blending a predetermined amount of such a lubricant, the surface characteristics such as slip characteristics or torque characteristics in the coating film can be adjusted efficiently. That is, the lubricity on the coating film surface is a characteristic particularly required when the coated metal molded product is an article that frequently slides with other articles such as bolts and nuts.

Here, examples of suitable lubricants include fluororesin compounds and polyethylene compounds.
The reason for this is that such a lubricant has a small coefficient of friction and is excellent in chemical resistance, weather resistance, water resistance, etc. This is because the water resistance can be improved.
Accordingly, examples of such fluororesin compounds include fluorinated acrylate resins, vinylidene fluoride resins, fluorinated urethane resins, fluorinated amino resins, polytrifluoroethylene resins, polytetrafluoroethylene resins, polyhexafluoropropylene resins, fluoropolymers. Ethylene propylene copolymer resin, polychlorotrifluoroethylene resin, ethylene-tetrafluoroethylene copolymer resin, tetrafluoroethylene-hexafluoropropylene copolymer resin, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer resin alone or A combination of two or more types can be mentioned.
Furthermore, examples of the polyethylene compound include nonionic emulsions based on polyethylene wax, nonionic emulsions based on modified polyethylene wax, anionic emulsions based on polyethylene wax, and anionic emulsions based on modified polyethylene wax. Singly or in combination of two or more, such as a cationic emulsion based on polyethylene wax and a cationic emulsion based on modified polyethylene wax.

(2) Compounding quantity Moreover, it is preferable to make the compounding quantity of the lubricant as (g) component into the value within the range of 0.5-30 weight part with respect to 100 weight part of silicone compounds.
This is because when the blending amount of such a lubricant is less than 0.5 parts by weight, it may be difficult to obtain sufficient effects such as improvement in lubricity, rust prevention and water resistance. .
On the other hand, when the blending amount of the lubricant exceeds 30 parts by weight, it may be difficult to blend uniformly in the aqueous coating composition.
Therefore, the blending amount of the lubricant is more preferably set to a value within the range of 5 to 25 parts by weight, and further preferably set to a value within the range of 10 to 20 parts by weight with respect to 100 parts by weight of the silicone compound. .

8). Rust preventive agent (1) type Moreover, it is preferable that water-based coating-coating composition mix | blends a rust preventive agent, for example, a pyrazole type compound, a triazole type compound (an azole ring containing compound is included), etc. as (h) component. .
The reason for this is that, by blending these anticorrosive agents, similar to the phenolic hydroxyl group-containing compound, it reacts with iron to form an iron salt, thereby forming a complex compound and reducing oxygen permeation. is there.

Here, examples of the pyrazole compound include pyrazole, 3,5-dimethylpyrazole, 3-methyl-5-pyrazolone, and 3-amino-5-methylpyrazole.
The types of triazole compounds (including azole ring-containing compounds) include 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-tria Zaindolizine, methylbenzotriazole, 2-mercaptobenzothiazole, 2-mercaptobenzimidazole, (2-benzothia Riruchio) acetic acid, 3- (2-benzothiadiazole azide thio) propionic acid, and salts thereof.

(2) Compounding quantity Moreover, it is preferable to make the compounding quantity of a rust preventive agent into the value within the range of 0.1-15 weight part with respect to 100 weight part of silicone compounds.
The reason for this is that when the amount of the rust inhibitor becomes less than 0.1 parts by weight, it may be difficult to sufficiently obtain the effect of improving the rust prevention property by the pyrazole-based compound or the like. .
On the other hand, when the blending amount of the rust inhibitor exceeds 5 parts by weight, it may be difficult to blend uniformly in the aqueous coating composition.
Therefore, the blending amount of the rust inhibitor is more preferably set to a value within the range of 0.5 to 12 parts by weight, and further preferably set to a value within the range of 1 to 8 parts by weight.

9. Additives In addition, in order to adjust the viscosity of the aqueous coating composition and the mechanical properties of the coating film to be formed, glass, quartz, aluminum hydroxide, alumina, kaolin, talc, calcium carbonate, calcium silicate, water Inorganic fillers such as magnesium oxide, organic fillers such as acrylic resin powder, epoxy resin powder, and polyester resin powder; colorants such as carbon black, bengara, phthalocyanine blue, cream yellow, titanium dioxide; metal powder; release agent It is preferable to add.
Furthermore, it is preferable to add, for example, a thermosetting resin or a metal alkoxide in order to improve the film formability of the coating film or improve the adhesion. More specifically, as the thermosetting resin, for example, an epoxy resin, a phenol resin, a maleimide resin, a urea resin, a polyimide resin, a vinyl ester resin, a silicone compound, or an unsaturated polyester resin may be used alone or in combination of two or more. Combinations are mentioned.

[Second Embodiment]
The second embodiment is an aqueous coating composition comprising the following components (a) to (e) on the surface of a metal molded article, wherein the silicone compound as the component (a) is a tetraalkoxysilane, alkyl At least one selected from the group consisting of trialkoxysilane and dialkyldialkoxysilane (however, in the case of an alkyl group, it is a methyl group, an ethyl group, a propyl group or a butyl group, and in the case of an alkoxy group, it is a methoxy group, an ethoxy group or a propoxy group) It is a coated metal molded article formed with a coating film formed by curing the aqueous coating paint composition .
(A) Silicone compound 100 parts by weight (b) Organic resin component having a hydroxyl value in the range of 1 to 500 mgKOH / g
15 to 200 parts by weight (c) phenolic hydroxyl group-containing compound 0.1 to 30 parts by weight (d) (b) component crosslinking agent 0.05 to 5 parts by weight (e) aqueous solvent 100 to 2000 parts by weight The coated metal molded article of the second embodiment will be specifically described within a range that does not overlap with the description relating to the aqueous coating paint composition of the first embodiment.

1. Metal molded product The type of metal molded product to be coated with the water-based coating composition is not particularly limited. For example, a headrest, a bolt, a nut, a tin, a nail, a bolt, a nut, a screw, a washer, a clamp, Pins, gibbles, coils, nets, bars, H steel, golf club shafts, umbrella frames, steel furniture, home appliance housings, and the like are preferable.
The material of the metal molded product is not particularly limited, and examples thereof include carbon steel, alloy steel, stainless steel, special steel, copper, silver, nickel, and platinum.
Therefore, the metal molded product made of such a material may be processed into a desired shape such as a plate shape or a rod shape by a method such as rolling, casting, or drawing, or may be a building material, a construction machine, a ship. It may be a member and a part such as a bridge, an automobile, and a container.

Here, as a typical example of a metal molded product, an automotive headrest stay 20 and a headrest 50 using the same will be described in detail with reference to FIG.
That is, the headrest stay 20 for an automobile is basically composed of an iron pipe or the like, and stress concentration is concentrated at both the leg portions 20a and 20b, the horizontal portion 20c connecting them, and further at these joint portions. And a curved portion 20d for prevention.

Further, both leg portions 20a, 20b of the headrest stay 20 are inserted into large and small insertion holes 66, 68 provided in a seat 70 of an automobile or the like, and are configured to be movable in the vertical direction while sliding.
A plurality of notches 60 are provided in either one of the leg portions 20a and 20b of the headrest stay 20, and any one of the notches 60 and a metal fitting (not shown) accommodated in the stopper 62 are engaged. Match.

On the other hand, the stopper 62 is provided with a release knob 64 for releasing the engagement between the notch 60 and the metal fitting inside the stopper so that the headrest 50 can be moved for further positioning or the like.
Further, a cavity 52 having a hollow portion inside is integrally provided around the headrest stay 20 via a welded joint portion 54. That is, the cavity 52 is an example, but it is a rice ball type, is divided into a front part and a rear part, and surrounds the headrest stay 20 so as to enclose the headrest stay 20, and via the welded joint part 54. Thus, the headrest stay 20 is firmly fixed.
A covering 53 including a cushioning material or the like is provided around the cavity 52, thereby forming a headrest 50 having excellent cushioning properties, light weight, mechanical strength, and the like. Are provided at predetermined positions.

2. Coating Film (1) Aqueous Coating Paint Composition The aqueous coating paint composition is the same as the contents described in the first embodiment, and thus the description thereof is omitted here.

(2) Thickness Also, the thickness of the coating film can be appropriately changed according to the type of metal molded article to be coated, but it is usually preferable to set the value within the range of 1 to 100 μm.
The reason for this is that when the thickness of the coating film is less than 1 μm, the mechanical strength, rust prevention, or adhesion may be lowered.
On the other hand, when the thickness of the coating film exceeds 100 μm, it may be difficult to apply the coating time excessively or uniformly.
Therefore, the thickness of the coating film is more preferably set to a value within the range of 5 to 50 μm, and further preferably set to a value within the range of 8 to 30 μm.

[Third Embodiment]
The third embodiment is a method for producing a coated metal molded article, which includes the following steps (1) to (3) in order.
(1) Step of preparing a metal molded product (2) An aqueous coating composition containing the following components (a) to (e) for the metal molded product, wherein the silicone compound as component (a) is tetra At least one selected from the group consisting of alkoxysilanes, alkyltrialkoxysilanes and dialkyldialkoxysilanes (provided that alkyl groups are methyl, ethyl, propyl, or butyl groups, and alkoxy groups are methoxy groups, an ethoxy group or a propoxy group.) the organic resin component applying an aqueous coating coating composition (a) a silicone compound 100 parts by weight of (b) hydroxyl value is a value within a range of 1~500mgKOH / g is
15 to 200 parts by weight (c) phenolic hydroxyl group-containing compound 0.1 to 30 parts by weight (d) (b) component crosslinking agent 0.05 to 5 parts by weight (e) aqueous solvent 100 to 2000 parts by weight (3) Step of Curing Aqueous Coating Paint and Forming Coating Film Third Embodiment To the extent that it does not overlap with the description relating to the aqueous coating paint composition of the first embodiment and the coated metal molded article of the second embodiment The method for producing the coated metal molded article will be specifically described.

1. Preparation Step of Metal Molded Product The preparation step of the metal molded product is a step of preparing the headrest stay or the like that is the base material of the headrest described in the second embodiment.
Therefore, it is preferable to perform a cleaning process on the metal molded product or perform a blasting process or the like on the surface of the metal molded product before performing the coating film forming step.
More specifically, as shown in FIG. 3, before the coating process (S3), the metal molded product is subjected to a degreasing process (S1) and a blasting process (S2) to remove impurities on the surface, It is preferable to improve the adhesiveness with the coating film to be formed by forming unevenness.

2. Coating Film Forming Process The coating film forming process is a process in which an aqueous coating paint composition is applied and cured to form a predetermined coating film.
More specifically, as shown in FIG. 3, it is preferable to carry out the coating step (S3) to apply a water-based coating composition on the surface of the metal molded article to form a uniform coating film.
And after implementing an application | coating process (S3), it is preferable to form a coating film (cured coating film) through a preliminary curing process (S4) and a main curing process (S5).

Here, the application method of the aqueous coating paint composition is not particularly limited, but for example, dip coating (dip coating method), spray coating, spin coating, tumbler coating, roll coating, gravure coating, etc. are used. Is preferred.
More specifically, for example, when processing a headless stay, it is preferable to apply uniformly to the headrest stay 20 using a dip coating apparatus 10 as shown in FIG.

That is, by using the dip coating apparatus 10 shown in FIG. 4, an approximately U-shaped headrest stay 20 made of an iron pipe having a diameter of 8 to 15 mm is attached to the tip of a hook-shaped suspension attached to a long object. Hanging as a parallel array of rows.
Next, the conveyor device 12 is moved in the direction of arrow A1 at a speed of 10 to 50 m / min and stopped above the degreasing tank. In this state, as shown in FIG. 4, the long object holder 16 of the conveyor device 12 is lowered in the direction of the arrow B1 and immersed in the degreasing liquid for 30 seconds to 3 minutes, and a predetermined ultrasonic vibration is applied. Apply and clean the surface of the headrest stay 20.
Thereafter, the long object holder 16 of the conveyor device 12 is raised in the direction of the arrow B 1 and further moved in the direction of the arrow A 2 to stop the plurality of headrest stays 20 above the immersion tank 24.

Next, the long object holder 16 of the conveyor device 12 is lowered in the direction of the arrow B2, and with respect to the stirring bath 24 in which the aqueous coating paint composition 24a (temperature: 20 to 40 ° C.) is contained, A plurality of headrest stays 20 are immersed and dip-coated at the same time.
Next, the long object holder 16 of the conveyor device 12 is raised in the direction of the arrow B2, and further moved in the direction of the arrow A3, so that the plurality of headrest stays 20 are guided to the heating furnace 26.

  Then, using the drying furnace 26, while moving the plurality of headrest stays 20 coated with the non-fluorine resin paint at a predetermined speed in the direction of arrow A4, heating is performed at 130 ° C. for 30 minutes to form a coating film having a thickness of 5 μm. It heat-drys and collect | recovers as the headrest stay 20 with a coating film.

In addition, although it does not restrict | limit especially about the curing conditions for hardening a coating film using a drying furnace, For example, it is preferable to heat-process at the temperature of 100-280 degreeC, and time for 1 to 180 minutes.
And in order to achieve more uniform and short-time curing, as shown in FIG. For example, as a first stage, heating is performed under conditions of a temperature of 100 to 130 ° C. for a time of 1 to 60 minutes, and a pre-curing step (S4) is performed. It is preferable to carry out the main curing step (S5) by heating under conditions of 60 minutes.
In addition, as shown in FIG. 3, after the main curing step (S5), it is preferable to provide an inspection step (S6) to inspect the state of the cured coating film, adhesion, and the like.

  EXAMPLES Hereinafter, although an Example is shown and this invention is demonstrated further in detail, this invention is not limited to these Examples.

[Example 1]
1. Preparation of Covered Metal Molded Product A headrest stay 20 as shown in FIG. 2 was prepared as a metal molded product, and the surface thereof was degreased using trichlorethylene and an alkaline cleaner.
That is, such a headrest stay is basically composed of an iron pipe or the like, both leg portions, a horizontal portion connecting them, and a curved portion for preventing stress concentration at these joint portions. And.

Next, using a dipping device 10 as shown in FIG. 4, it was immersed in an aqueous coating composition (viscosity: 100 mP · sec / 25 ° C., solid content: 23% by weight) comprising the following blending components.
(A1) Ethyl silicate 100 parts by weight (B1) Water-dispersible polyester resin Vironal MD-1200 (manufactured by Toyobo Co., Ltd., hydroxyl value 5.8 mgKOH / g, acid value 1.7 mgKOH / g, pH 5.5)
50 parts by weight (C1) vanadium tannate 2 parts by weight (D1) titanium diisopropoxybis (triethanolamate) 1 part by weight (E1) isopropanol 70 parts by weight (E2) 500 parts by weight of water (F1) 3-glycid Xypropyltriethoxysilane 2 parts by weight (G1) Polytetrafluoroethylene 10 parts by weight (H1) 3- (2-benzothiazylthio) propionic acid 5 parts by weight Then, heat in a heating furnace at 130 ° C. for 30 minutes. Then, a coating film having a thickness of 10 μm was formed to obtain a headrest stay as a coated metal molded product.

Moreover, the hydroxyl value of the polyester resin (B1) described above was measured as follows.
That is, first, 50 g of a polyester resin was dissolved in a mixed solvent of 60 g of toluene and 60 g of ketone, 50 g of diphenylmethane-4,4′-diisocyanate was added, and reacted at 80 ° C. for 2 hours.
Next, an excess di-normal butylamine solution was added to the residual isocyanate group in the reaction solution to cause a reaction, and the remaining di-normal butyl amine was back titrated with hydrochloric acid to obtain a hydroxyl value (mgKOH / g).

Moreover, the acid value of the polyester resin (B1) described above was measured as follows.
That is, first, 0.2 g of a polyester resin was dissolved in 20 ml of chloroform.
Subsequently, the obtained solution was titrated with a 0.1 N potassium hydroxide ethanol solution to obtain an acid value (mgKOH / g).

  Furthermore, although the polyester resin mentioned above was added with respect to other components in the state of the water dispersion (water: n-butyl cellosolve = 89:11), the viscosity (25 degreeC) of the water dispersion at this time is It was 1.6 mPa · s, the solid content concentration was 34% by weight, and the pH was 5.5.

2. Evaluation of aqueous coating paint composition and coated metal molded article (1) Storage stability of aqueous coating paint composition The obtained aqueous coating paint composition is stored in a dark room at 25 ° C. and 50% RH to generate precipitation. Was visually confirmed and evaluated according to the following criteria.
A: Precipitation is not confirmed even after 1 month from the start of storage.
○: Precipitation was confirmed after 3 weeks from the start of storage.
Δ: Precipitation was confirmed when two weeks passed from the start of storage.
X: Precipitation was confirmed when one week passed from the start of storage.

(2) Evaluation of applicability Measure the thickness of each of the multiple points (8 points) of the coating film on the headrest stay obtained, calculate the maximum difference between the average value and the actually measured value of 8 points. Along with this, the applicability was evaluated.
A: The maximum difference is within ± 1 μm.
○: The maximum difference is within ± 2 μm.
Δ: The maximum difference is within ± 4 μm.
X: The maximum difference is more than ± 4 μm.

(3) Adhesion evaluation About the obtained headrest stay, the cross-cut tape peeling test based on JISD0202 was done.
That is, cellophane tape (Nichiban Co., Ltd., CT24) was bonded onto 100 square squares engraved on the coating film formed on the headrest stay, and then peeled off, following the criteria below. And evaluated.
A: All 100 cells remained without peeling.
○: 95 to 99 squares remained without peeling.
Δ: 80 to 94 squares remained without peeling.
X: 0-79 squares remained without peeling.

(4) Corrosion resistance evaluation by SST test About the obtained headrest stay, the corrosion resistance test by the SST test (temperature: 35 degreeC, salt spray of 5% of density | concentration) based on JISZ2371 was done, and time until red rust generate | occur | produced was measured.
A: Time until red rust is generated is 72 hours or more.
○: Time until red rust is generated is 48 hours or more.
(Triangle | delta): Time until red rust generate | occur | produces is 24 hours or more.
X: Time until red rust occurs is less than 24 hours.

(5) Phase separation evaluation The obtained headrest stay was subjected to elemental analysis using an electron beam microanalyzer (EPMA), and the distribution of carbon (C) in the film thickness direction of the coating film was measured. And the component (b) were visually separated in the film thickness direction of the coating film, and the phase separation property was evaluated according to the following criteria.
For reference, the obtained EPMA chart (carbon (C) distribution state) is shown in FIG.
Here, the relationship between the color in the EPMA chart and the abundance of carbon is such that the abundance of carbon decreases in the order of white, pink, red, yellow, green, light blue, and blue. Therefore, the abundance of carbon in the white region is relatively the largest, and the abundance of carbon in the blue region is the smallest.
Further, from the EPMA chart shown in FIG. 5, since the carbon existing region is unevenly distributed on the iron plate side of the rust inhibitor-containing resin layer, it is determined from the configuration of each component of the rust inhibitor-containing resin layer. It is understood that the polyester resin having a hydroxyl value of is unevenly distributed on the iron plate side.
Note that the EPMA chart shown in FIG. 5 is a photograph substitute diagram generated based on a photograph taken at a magnification of 2,000 times.
The reason for using such a photo substitute diagram is that when a photo is used as it is as a drawing, the quality of the photo in the gazette or the like may deteriorate and become unclear. The same applies to FIGS.
A: It can be determined that the phases are clearly separated.
○: It can be judged that the phases are almost clearly separated.
Δ: It can be judged that the phases are separated clearly.
X: It is difficult to determine whether or not the phases are separated.

[Examples 2 to 4]
In Examples 2-4, the influence of the compounding quantity of the organic resin component which is (b) component in water-based coating-coating composition was examined. In other words, the content of the predetermined polyester resin was 100 parts by weight of the silicone compound, 25 parts by weight in Example 2, 100 parts by weight in Example 3, and 200 parts by weight in Example 4, respectively. A coated metal molded article was produced and evaluated in the same manner as in Example 1.
In addition, the EPMA chart (carbon (C) distribution state) in Example 3 is shown in FIG. 6, and the EPMA chart (carbon (C) distribution state) in Example 4 is shown in FIG.

[Examples 5 to 6]
In Examples 5-6, the kind of polyester resin which is (b) component in water-based coating-coating composition was examined. That is, in Example 5, the coated metal molded article was produced in the same manner as in Example 1 except that the following bilonal MD-1500 (B2) was used, and in example 6, the following bilonal MD-1480 (B3) was used. evaluated.
Byronal MD-1500: manufactured by Toyobo Co., Ltd., hydroxyl value 12 mgKOH / g, acid value 1.7 mgKOH / g, pH 6
Byronal MD-1480: manufactured by Toyobo Co., Ltd., hydroxyl value 2.8 mgKOH / g, acid value 2.8 mgKOH / g, pH 5.5

[Examples 7 to 8]
In Examples 7 to 8, the influence of the type of the phenolic hydroxyl group-containing compound that is the component (c) in the aqueous coating composition was examined. That is, Example 7 was the same as Example 1 except that molybdenum tannate (C2) was used as the component (c) and tungsten tannate (C3) was used as the component (c) in Example 8. A coated metal molded product was produced and evaluated.

[Example 9]
In Example 9, the influence of the type of the crosslinking agent as the component (d) in the aqueous coating composition was examined. That is, the coated metal molded article was the same as in Example 1 except that the zirconium chloride compound aminocarboxylic acid (manufactured by Matsumoto Kosho Co., Ltd., ORGATIZ ZB-126, (D2)) was used as the component (d). Manufactured and evaluated.

[Example 10]
In Example 10, the influence of the type of lubricant as the component (g) in the aqueous coating composition was examined. That is, a coated metal molded article was produced and evaluated in the same manner as in Example 1 except that the nonionic emulsion (G2) based on the modified polyethylene wax was used as the component (g).
Moreover, the EPMA chart (carbon (C) distribution state) in Example 10 is shown in FIG.
From the EPMA chart shown in FIG. 8, the carbon existing region contained in the nonionic emulsion (F2) based on the modified polyethylene wax is unevenly distributed on the surface side (environment side) of the rust inhibitor-containing resin layer. It is understood that PEW has a distribution that effectively contributes to improving the lubricity on the surface of the coating film. In addition, in the EPMA chart shown in FIG. 8, the carbon existing region unevenly distributed on the iron plate side of the rust preventive agent-containing resin layer indicates the distribution of carbon atoms contained in the polyester resin having a predetermined hydroxyl value.

[Example 11]
In Example 11, a coated metal molded article was produced and evaluated in the same manner as in Example 1 except that the rust inhibitor as the component (h) was not blended in the aqueous coating paint composition.

[Example 12]
In Example 12, the influence of the type of the organic resin component having a predetermined hydroxyl value as the component (b) and the crosslinking agent as the component (d) was examined. That is, an aqueous coating composition comprising the following blending components was produced, and a coated metal molded article was produced and evaluated in the same manner as in Example 1.
(A1) Ethyl silicate 100 parts by weight (B4) Water dispersible phenoxy resin PKHW-34 (manufactured by InChem Co., Ltd., hydroxyl value 250 mgKOH / g, acid value 47 mgKOH / g, pH 7.3) 50 parts by weight (C1) tannic acid Vanadium 2 parts by weight (D3) Water-dispersed blocked isocyanate (Elastolone BN-11, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) 1 part by weight (E1) Isopropanol 70 parts by weight (E2) Water 500 parts by weight (F1) 3-Gly Sidoxypropyltriethoxysilane 2 parts by weight (G1) Polytetrafluoroethylene 10 parts by weight (H1) 3- (2-benzothiazylthio) propionic acid 5 parts by weight In addition, the EPMA chart in Example 12 (carbon (C) FIG. 9 shows the distribution state of (1).

[Examples 13 to 15]
In Examples 13 to 15, the influence of the blending amount of the phenoxy resin as the component (b) in the aqueous coating composition was examined. That is, the content of the phenoxy resin having a predetermined hydroxyl value was 25 parts by weight in Example 13, 100 parts by weight in Example 14, and 200 parts by weight in Example 15 with respect to 100 parts by weight of the silicone compound. Were manufactured and evaluated in the same manner as in Example 12, respectively.

[Examples 16 to 17]
In Examples 16 to 17, the type of the phenoxy resin as the component (b) in the aqueous coating composition was examined. That is, in Example 15, the coated phenoxy resin PKHW-35 (B5) was used, and in Example 16, the following phenoxy resin PKHW-38 (B6) was used. Manufactured and evaluated.
PKHW-35: manufactured by InChem Co., Ltd., hydroxyl value 260 mgKOH / g, acid value 57 mgKOH / g, pH 7.3
PKHW-38: manufactured by InChem Co., Ltd., hydroxyl value 240 mgKOH / g, acid value 50 mgKOH / g, pH 7.3

[Example 18]
In Example 18, the influence of the mixed organic resin component in the aqueous coating composition was examined. That is, (b) as an organic resin component having a predetermined hydroxyl value (B7 = B1 + B4), Vylonal MD-1200 (B1), which is a polyester resin used in Example 1, and phenoxy resin PKHW− used in Example 12 34 (B4) was mixed so as to be 50:50 (weight ratio) and contained in a total of 50 parts by weight with respect to 100 parts by weight of the silicone compound, as in Example 12. Coated metal molded articles were manufactured and evaluated.
In addition, the hydroxyl value of the mixed resin described above was 127.9 mgKOH / g, the acid value was 24.4 mgKOH / g, and the pH was 6.5.

[Comparative Examples 1-2]
In Comparative Examples 1 and 2, the effect of using an organic resin component having no predetermined hydroxyl value in the aqueous coating composition was examined. That is, as an organic resin component having no predetermined hydroxyl value, the following aqueous urethane resin R-9660 (B8) was used in Comparative Example 1, and the following aqueous urethane acrylic resin R-9699 (B9) was used in Comparative Example 2. A coated metal molded article was produced and evaluated in the same manner as in Example 1 except that it was used.
R-9660: DSM NeoResins Co., Ltd., hydroxyl value 0.5 mgKOH / g, acid value 30 mgKOH / g, pH 8.3
R-9699: DSM NeoResins Co., Ltd., hydroxyl value 0.8 mgKOH / g, acid value 15 mgKOH / g, pH 8.3

[Comparative Examples 3 to 4]
In Comparative Examples 3 to 4, the influence of the blending amount of the polyester resin having a predetermined hydroxyl value (b) in the aqueous coating composition was examined.
That is, the blending amount of the polyester resin having a predetermined hydroxyl value was 10 parts by weight in Comparative Example 3 and 250 parts by weight in Comparative Example 4 with respect to 100 parts by weight of the silicone compound, respectively. A coated metal molded product was manufactured and evaluated.

[Comparative Example 5]
In Comparative Example 5, the effect of not using the component (d) (the crosslinking agent of the component (b)) in the aqueous coating composition was examined.
That is, a coated metal molded article was produced and evaluated in the same manner as in Example 1 except that the component (d) was not used.

[Example 19]
In Example 19, the influence of the type and blending amount of the phenolic hydroxyl group-containing compound which is the component (c) in the aqueous coating paint composition was mainly examined. That is, an aqueous coating composition comprising the following blending components was manufactured, and a headrest stay was manufactured and evaluated in the same manner as in Example 1.
(A1) Ethyl silicate 100 parts by weight (B2) Water dispersible polyester resin Vironal MD-1500 (manufactured by Toyobo Co., Ltd., hydroxyl value 12 mgKOH / g, acid value 1.7 mgKOH / g, pH 6) 40.8 parts by weight (C1 ) Vanadium tannate 0.4 parts by weight (C4) 12 parts by weight of tannic acid (D4) Titanium lactate (manufactured by Matsumoto Kosho Co., Ltd., ORGATICS TC-315)
0.8 parts by weight (E1) Isopropanol 70 parts by weight (E2) Water 500 parts by weight (F1) 3-glycidoxypropyltriethoxysilane 0.32 parts by weight (G2) Nonionic emulsion based on modified polyethylene wax
7.2 parts by weight (H1) 3- (2-benzothiazylthio) propionic acid 8 parts by weight

In Example 19, in addition to the headrest stay described above, a steel bolt and nut, and an iron plate were coated by forming a 10 μm thick coating film by the same method as the headrest stay. Corrosion resistance was evaluated by an SST test using a metal molded product.
Here, FIG. 10A shows a photograph substitute diagram of the iron plate before the SST test, and FIG. 10B shows a photograph substitute diagram of the iron plate after the SST test is performed for 72 hours.
For comparison, FIG. 10 (c) shows a photograph substitute diagram after the SST test was performed for 72 hours on an iron plate manufactured using the aqueous coating paint composition of Comparative Example 1.
10 (a) to 10 (c), the iron plate manufactured using the aqueous coating paint composition of Example 19 can effectively rust and paint even when the SST test is performed for 72 hours. It is understood that the occurrence of film peeling can be prevented.
On the other hand, the iron plate manufactured using the aqueous coating paint composition of Comparative Example 1 can be confirmed that red rust is generated around the hole provided in the upper portion of the iron plate when the SST test is performed for 72 hours.
Moreover, in the edge part of an iron plate, it can confirm that a coating film peels partially and slight red rust has generate | occur | produced.

[Examples 20 to 22]
In Examples 20-22, the influence of the compounding quantity of the phenolic hydroxyl group containing compound which is (c) component was further examined. That is, in Example 20, as component (c), the amount of vanadium tannate (C1) was 0.2 parts by weight, and the amount of tannic acid (C4) was 6 parts by weight.
In Example 21, as component (c), the amount of vanadium tannate (C1) was 0.8 parts by weight, and the amount of tannic acid (C4) was 24 parts by weight.
Furthermore, in Example 22, as component (c), the amount of vanadium tannate (C1) was 6 parts by weight, and the amount of tannic acid (C4) was 6 parts by weight.
Other than that, coated metal molded articles were produced and evaluated in the same manner as in Example 19.

[Example 23]
In Example 23, the influence of the type of the organic resin component having a predetermined hydroxyl value as the component (b) was examined. That is, an aqueous coating composition comprising the following blending components was produced, and a coated metal molded product was produced and evaluated in the same manner as in Example 19.
(A1) Ethyl silicate 100 parts by weight (B4) Water dispersible phenoxy resin PKHW-34 (manufactured by InChem Co., Ltd., hydroxyl value 250 mgKOH / g, acid value 47 mgKOH / g, pH 7.3) 40.8 parts by weight (C1) Vanadium tannate 0.4 parts by weight (C4) tannic acid 12 parts by weight (D3) water-dispersed blocked isocyanate (Elastolone BN-11, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) 1 part by weight (E1) isopropanol 70 parts by weight ( F1) 3-glycidoxypropyltriethoxysilane 0.32 parts by weight (G2) nonionic emulsion based on modified polyethylene wax
7.2 parts by weight (H1) 3- (2 benzothiazylthio) propionic acid 8 parts by weight

[Examples 24-26]
In Examples 24-26, the influence of the blending amount of the phenolic hydroxyl group-containing compound as component (c) was further examined. That is, in Example 24, as component (c), the amount of vanadium tannate (C1) was 0.2 parts by weight, and the amount of tannic acid (C4) was 6 parts by weight.
In Example 25, as component (c), the amount of vanadium tannate (C1) was 0.8 parts by weight, and the amount of tannic acid (C4) was 24 parts by weight.
Furthermore, in Example 26, as component (c), the amount of vanadium tannate (C1) was 6 parts by weight, and the amount of tannic acid (C4) was 6 parts by weight.
Other than that, coated metal molded articles were produced and evaluated in the same manner as in Example 23.

As described above in detail, according to the present invention, (a) a silicone compound, (b) an organic resin component having a predetermined hydroxyl value, (c) a phenolic hydroxyl group-containing compound, (d) the component (b) described above. A coating film having not only excellent storage stability but also good coating properties, adhesion, and corrosion resistance, by the aqueous coating coating composition containing each of the crosslinking agent and (e) the aqueous solvent at a predetermined blending ratio. Can now be obtained.
More specifically, with respect to metal molded products such as headrests, etc. without using a chromium compound, or even when a base layer such as a zinc-containing porous coating layer is omitted, excellent adhesion, A coating film having durability, smoothness and rust prevention property can be formed easily and stably.
Therefore, the aqueous coating paint composition of the present invention is expected to be widely used in the fields of electrical products, building materials, construction machinery, ships, bridges, automobiles, and the like as an alternative technique for chromium plating.

10: Dip coating device, 12: Moving device (conveyor device), 14: Long object, 16: Long object holder, 18: Hanging tool, 18a: Tip part, 20: Headrest stay, 20a, 20b: Both leg parts , 20c: horizontal part, 20d: curved part, 22: degreasing tank, 22a: degreasing liquid, 24: immersion tank, 24a: aqueous coating paint composition, 26: heating furnace, 26a: hot air blowing part, 26b: hot air, 50 : Headrest, 52: Cavity, 53: Cover, 54: Welded joint, 60: Notch, 62: Stopper, 64: Metal fitting, 66: Large insertion hole, 68: Small insertion hole, 70: Seat

Claims (8)

An aqueous coating composition comprising the following blending components (a) to (e), wherein the silicone compound as component (a) is selected from the group consisting of tetraalkoxysilane, alkyltrialkoxysilane, and dialkyldialkoxysilane: An aqueous coating, characterized in that it is a methyl group, an ethyl group, a propyl group or a butyl group in the case of an alkyl group, and a methoxy group, an ethoxy group or a propoxy group in the case of an alkoxy group. Paint composition.
(A) Silicone compound 100 parts by weight (b) Organic resin component having a hydroxyl value in the range of 1 to 500 mgKOH / g
15 to 200 parts by weight (c) phenolic hydroxyl group-containing compound 0.1 to 30 parts by weight (d) (b) component crosslinking agent 0.05 to 5 parts by weight (e) aqueous solvent 100 to 2000 parts by weight   2. The aqueous coating composition according to claim 1, wherein the organic resin component as the component (b) is a polyester resin or a phenoxy resin, or one of them.   The aqueous coating paint composition according to claim 1 or 2, wherein the component (c) is a tannic acid compound.   The water-based coating composition according to any one of claims 1 to 3, wherein the component (d) is at least one of an epoxy compound, an isocyanate compound, an aziridine compound, and an organometallic compound.   As a component (f), a silane coupling agent is further included, and the blending amount thereof is set within a range of 0.1 to 30 parts by weight with respect to 100 parts by weight of the silicone compound as the component (a). The aqueous coating paint composition according to any one of claims 1 to 4, wherein   The component (g) further contains a lubricant, and the blending amount thereof is set to a value within the range of 0.5 to 30 parts by weight with respect to 100 parts by weight of the silicone compound as the component (a). The aqueous coating paint composition according to any one of claims 1 to 5. An aqueous coating composition containing the following compositions (a) to (e) on the surface of a metal molded article, wherein the silicone compound as component (a) is a tetraalkoxysilane, an alkyltrialkoxysilane, and a dialkyldialkoxy At least one selected from the group consisting of silanes (however, in the case of an alkyl group, it is a methyl group, an ethyl group, a propyl group or a butyl group, and in the case of an alkoxy group, it is a methoxy group, an ethoxy group or a propoxy group). A coated metal molded article formed with a coating film obtained by curing an aqueous coating paint composition .
(A) Silicone compound 100 parts by weight (b) Organic resin component having a hydroxyl value in the range of 1 to 500 mgKOH / g
15 to 200 parts by weight (c) phenolic hydroxyl group-containing compound 0.1 to 30 parts by weight (d) (b) component crosslinking agent 0.05 to 5 parts by weight (e) aqueous solvent 100 to 2000 parts by weight The manufacturing method of the covering metal molded product characterized by including the following (1)-(3) process sequentially.
(1) Step of preparing a metal molded product (2) For the metal molded product, an aqueous coating composition containing the following components (a) to (e), wherein the silicone compound as component (a): At least one selected from the group consisting of tetraalkoxysilane, alkyltrialkoxysilane and dialkyldialkoxysilane (however, in the case of an alkyl group, it is a methyl group, an ethyl group, a propyl group or a butyl group, and in the case of an alkoxy group, a methoxy group) , an ethoxy group or a propoxy group.) the organic resin component applying an aqueous coating coating composition (a) a silicone compound 100 parts by weight of (b) hydroxyl value is a value within a range of 1~500mgKOH / g is
15 to 200 parts by weight (c) phenolic hydroxyl group-containing compound 0.1 to 30 parts by weight (d) (b) component crosslinking agent 0.05 to 5 parts by weight (e) aqueous solvent 100 to 2000 parts by weight (3) A step of curing the aqueous coating paint to form a coating film

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