JP2012121323A - Chromate-free colored coated metal sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive chromate-free colored coated metal sheet including no hexavalent chrome having high environmental load and extremely excellent in designability (coloring and occluding properties including a processing part), moisture resistance, corrosion resistance, processability, scratch resistance, chemical resistance and the like.SOLUTION: There is provided a chromate-free colored coated metal sheet in which a colored coating film (α) comprising an organic resin (A) as a film-forming component, a coloring pigment (B) and silica particles (C) is formed on at least one side of a metal sheet. The surface roughness of the metal sheet is 0.7-1.5 μm in an arithmetic average roughness Ra, the peak number PPI of roughness curve per 1 inch (2.54 cm) length of the average line direction of a roughness curve is 120 to 300, and the thickness of the colored coating film (α) is 2 to 10 μm.

Description

  The present invention is a low-cost design chromate-free colored painted metal that is highly excellent in corrosion resistance, workability, scratch resistance, etc., in which a colored coating film not containing hexavalent chromium having high environmental impact is formed on at least one surface of a metal plate. Regarding the board.

  Clear pre-coating that uses the metallic feeling of pre-coated metal plates and metal surfaces coated with colored organic coatings instead of post-painted products that have been painted after conventional molding for home appliances, building materials, and automobiles. Metal plates and the like have come to be used. These designable metal plates are made by coating a colored organic film on a rust-proof steel plate or plated steel plate, or by applying a clear coating on a metal plate exhibiting a metallic luster, and have a beautiful appearance. However, it has processability and good corrosion resistance.

  For example, Patent Document 1 discloses a technique for obtaining a pre-coated steel sheet excellent in workability, stain resistance, and hardness by defining the structure of the film. On the other hand, Patent Document 2 discloses a precoated steel sheet having improved end face corrosion resistance by using a specific chromate treatment liquid. These pre-coated steel sheets have corrosion resistance, workability, and paint adhesion due to the combined effect of the plating film, chromate-treated film, and chrome-based anti-corrosive pigment (primary coating). The purpose is to improve productivity and quality.

  However, in consideration of the environmental load of hexavalent chromium that may be eluted from the chromate-treated film and the organic film containing the chromium-based rust-preventive pigment, the demand for a non-chromium anti-rust treatment and a non-chromium organic film has been increasing recently. . On the other hand, for example, Patent Document 3 and Patent Document 4 disclose non-chromium precoated steel sheets having excellent corrosion resistance, which have already been put into practical use.

  The coating used for these precoated steel sheets is thick with a coating film thickness of 10 μm or more. In addition, since a large amount of solvent-based paint is used, special coating equipment such as an incinerator and odor control equipment is required, and it is generally manufactured on a dedicated paint line. That is, since an extra coating process is passed in addition to the manufacturing process of the steel sheet as a coating original sheet, many costs are required in addition to the material cost required for coating. Therefore, the precoated steel sheet obtained is expensive.

  However, due to the diversification of user needs, there is a demand for design steel sheets in fields where the purpose can be sufficiently achieved if they have durability under daily use conditions such as home appliances and interior building materials, and lower priced products are required. ing. That is, conventional expensive pre-coated steel sheets alone are not sufficient to meet diversified demands.

  As a designable metal plate that can be manufactured at low cost for such needs, for example, a colored steel plate provided with a colored resin layer having a thickness of 5 μm or less in Patent Document 5 has a specific roughness in Patent Document 6. A colored steel sheet having a colored film on the steel sheet surface is disclosed. However, these colored steel sheets are designed to ensure corrosion resistance by providing a chromate-treated film, and thus cannot meet the recent needs for non-chromation. In addition, since it is not designed to take into account the resistance to scratches that occur during handling and press molding, and the concealment of the part where the colored layer is stretched by press molding, the appearance of the scratched part and molded part There was also a problem that remarkably decreased.

  Patent Document 7 discloses a heat-resistant clear pre-coated metal plate having excellent design properties. The clear coating used here is relatively thin with a thickness of 10 μm or less, and is a non-chrome specification. However, a solvent-based paint is used as the paint for forming the clear coating. is required. In addition, although it is excellent in designability and workability, it has a problem that the scratch resistance is not sufficient.

In Patent Document 8, an electrogalvanized layer and a chemical conversion film are sequentially provided on at least one surface of a base steel sheet, and the surface roughness of the chemical conversion film is 1.0 to 1.6 μm in terms of arithmetic average roughness Ra, and the roughness. Disclosed is a surface-treated steel sheet having good conductivity, which has a peak number PPI of 300 to 500 per inch (2.54 cm) in the average line direction of the curve. It is described that a conversion film containing no chromium is used. It is also described that it is preferable to provide an organic resin layer that imparts corrosion resistance, scratch resistance, designability, etc. on the chemical conversion film, and in the examples, a relatively low adhesion amount (thin film) of 0.5 g / m ² Thick) organic resin layer. Patent Document 8 relates to a surface treatment that increases the conductivity on the back side of a coated steel sheet that does not require a high degree of designability. When the conductivity (Ra, PPI) of the chemical conversion film is increased, the conductivity is ensured. It was invented with this idea. Therefore, even if it is applied to the surface side (surface that requires designability) of coated steel sheets that require low electrical conductivity and require high designability, the design surface such as designability, scratch resistance, workability, corrosion resistance, etc. It is difficult to ensure the required performance level.

JP-A-8-168723 Japanese Patent Laid-Open No. 3-100180 JP 2000-199075 A JP 2000-262967 A Japanese Patent Laid-Open No. 5-16292 JP-A-2-93093 JP 2008-149608 A JP 2010-121201 A

  In view of the above-mentioned situation, the present invention is a coated metal plate that does not contain hexavalent chromium, which is highly environmentally friendly, and has an inexpensive design chromate-free that has improved scratch resistance without degrading workability and corrosion resistance. The object is to provide a colored coated metal sheet.

  Generally, in order to improve the scratch resistance of a coated metal plate, it is important to make the coating film difficult to be damaged. In particular, in the case of a design-colored painted metal plate, the coating film is colored so that it is easy to be noticed when scratched, and because it is used for design applications, it is strict in appearance design quality. It is especially important to make it inconspicuous.

  In general, the scratches on the coating film are more conspicuous when they enter continuously, and become less noticeable as they become discontinuous. Therefore, based on the idea that the scratches can be made inconspicuous if the way the scratches enter the coating becomes discontinuous, the study focuses on the roughness of the surface of the metal plate that forms the coating. went. As a result, it was found that by providing irregularities on the metal plate surface more than a certain distance and increasing the distance between the protrusions more than a certain distance, even if the coating film is scratched, it tends to become discontinuous and inconspicuous. . A decrease in gloss on the entire surface of the colored coating film due to the formation of irregularities on the surface of the metal plate is also one of the factors that make the scratches on the coating film less noticeable. Specifically, when the arithmetic average roughness Ra of the metal plate surface is 0.7 μm or more and the number of peaks PPI per inch (2.54 cm) in the average line direction of the roughness curve is 300 or less, It was found that a design-colored painted metal plate having excellent scratch resistance (hardness of noticeable scratches on the coating film) can be obtained.

  In addition, the roughness of the surface of the metal plate does not affect the workability of the colored coated metal plate, but if the arithmetic average roughness Ra exceeds 1.5 μm, the corrosion resistance decreases, the average of the roughness curve It was found that when the number of peaks PPI per 1 inch (2.54 cm) in the linear direction was less than 120, the gloss of the coating film increased and the scratches were conspicuous.

  Therefore, when the arithmetic average roughness Ra of the metal plate surface is 0.7 to 1.5 μm and the number of peaks PPI per inch (2.54 cm) in the average line direction of the roughness curve is 120 to 300 Further, it was found that a design-oriented chromate-free colored painted metal plate excellent in all of scratch resistance, corrosion resistance, and workability was obtained.

The gist of the present invention completed based on the above findings is as follows.
(1) A chromate-free coating on which at least one surface of a metal plate contains an organic resin (A) as a film-forming component and a colored coating film (α) containing a color pigment (B) and silica particles (C) is formed. It is a colored coated metal plate, and the surface roughness of the metal plate is 0.7 to 1.5 μm in arithmetic average roughness Ra, and the length in the average line direction of the roughness curve is 1 inch (2.54 cm). A chromate-free colored coated metal sheet, wherein the number of permeation peak PPI is 120 to 300, and the film thickness of the colored coating film (α) is 2 to 10 μm.
(2) The chromate-free colored coated metal plate according to (1), wherein the organic resin (A) is a resin cured with a curing agent (D).
(3) The silica particles (C) contain spherical silica particles (C1) having an average particle diameter of 5 to 50 nm and spherical silica particles (C2) having an average particle diameter of 0.3 to 5 μm, The chromate-free colored painted metal plate according to the above (1) or (2).
(4) Any of the above (1) to (3), wherein the colored coating film (α) further contains at least one resin particle (E) selected from an acrylic resin and a silicon resin. 2. A chromate-free colored painted metal plate according to 1.
(5) The chromate-free colored coated metal sheet according to (4) above, wherein the resin particles (E) have an average particle diameter of 1 to 5 μm.
(6) The chromate-free colored painted metal plate according to any one of (1) to (5) above, wherein the colored pigment (B) contains carbon black (B1).
(7) The chromate-free colored painted metal plate according to any one of (1) to (6) above, wherein the colored pigment (B) contains titanium dioxide (B2).
(8) The chromate according to any one of (1) to (7) above, wherein the organic resin (A) contains a polyester resin (Ae) containing a sulfonic acid group in the structure. Free colored painted metal plate.
(9) The chromate-free colored coated metal plate according to (8), wherein the polyester resin (Ae) further contains a bisphenol structure in the structure.
(10) The chromate-free colored coated metal plate according to (8) or (9) above, wherein the organic resin (A) further contains a polyurethane resin (Au) containing a urea group in the structure. .
(11) The chromate-free colored painted metal plate according to any one of (1) to (10), wherein the colored coating film (α) further contains polyethylene resin particles (F). .
(12) The chromate-free colored coated metal plate according to (11), wherein the polyethylene resin particles (F) have an average particle diameter of 0.5 to 3 μm.
(13) The chromate-free colored coated metal plate according to any one of (1) to (12) above, wherein a base treatment layer (β) is provided below the colored coating film (α).
(14) The coating film (α) according to the above (1) to (13) is coated with an aqueous coating composition (X) containing a constituent component of the coating film (α) on at least one surface of a metal plate, The chromate-free colored coated metal plate according to any one of (1) to (13) above, which is formed by heating and drying.

  The design chromate-free colored painted metal plate of the present invention does not contain hexavalent chromium having high environmental impact, is inexpensive, and is extremely excellent in workability, corrosion resistance, scratch resistance, and the like. For this reason, it is very promising as an inexpensive high-design, high-value-added environment-friendly material, and the contribution to each industrial field is very large.

It is explanatory drawing which shows the roughness curve of the surface roughness regarding the definition of PPI.

  The chromate-free colored coated metal plate of the present invention has a colored coating film (α) containing an organic resin (A) as a film-forming component, a color pigment (B), and silica particles (C) on at least one surface of the metal plate. ) In which the roughness of the surface of the metal plate is 0.7 to 1.5 μm in terms of arithmetic average roughness Ra, and the length of the roughness curve in the average line direction. The peak number PPI per inch (2.54 cm) is 120 to 300, and the thickness of the colored coating film (α) is 2 to 10 μm.

  More specifically, the chromate-free colored coated metal plate of the present invention is an organic resin (A) that is a film-forming component of a coating film and contributes to improvement of scratch resistance, corrosion resistance, and workability of the colored coated metal plate. And a colored coating (B) containing a colored pigment (B) for coloring the coating and imparting design properties to the coated metal plate, and silica particles (C) contributing to improvement of the corrosion resistance and scratch resistance of the coated metal plate (α ) Is formed on at least one side of a metal plate as a base material, and the roughness of the surface of the metal plate is 0.7 to 1.5 μm in terms of arithmetic average roughness Ra, and in the average line direction of the roughness curve. While the peak number PPI per inch (2.54 cm) is 120 to 300, and the film thickness of the colored coating film (α) is 2 to 10 μm, the corrosion resistance and workability are not lowered. The scratch resistance is improved. The chromate-free colored coated metal plate of the present invention is provided with a non-chromium organic coating that does not contain hexavalent chromium, which is highly environmentally friendly, and this non-chromium organic coating does not contain an organic solvent in which a dedicated coating facility is indispensable. It can be formed by using a paint containing an aqueous solvent. Thus, according to the present invention, it is possible to provide an inexpensive high-design chromate-free colored painted metal plate that has both workability, corrosion resistance, and scratch resistance.

  When a colored coating film having the same thickness is compared with a non-colored (clear) coating film, scratches on the coating film are more noticeable in the colored coating film. The reason is that when a scratch is formed on the colored coating film, the color of the base metal plate that is different from the color of the coating film appears at the scratched portion when the scratch reaches the base metal plate. Moreover, even if it is a crack | wound which does not reach a base metal plate, the difference in gloss arises in a crack part and the other part, and the design property may be impaired. These scratches are more conspicuous in dark color than in light color. When coatings of the same color with different thicknesses are compared, the scratches on the coating are more noticeable in the thin coating. This is because the thinner the coating film, the easier it is to see the color of the base metal plate surface due to scratches, and the greater the difference in gloss between the scratched part and the other part. On the other hand, in terms of how the scratches enter the coating film, in general, discontinuous scratches (intermittent or speckled scratches) are more conspicuous than continuous scratches (linear scratches). It is hard to stand out, and the distance between adjacent scratches is less noticeable.

  Considering the case of a thin colored coating film with a film thickness of about 10 μm or less, the ease of noticeable scratches on the coating film is strongly influenced by the surface shape of the base metal plate compared to a coating film with a larger film thickness. . In the thick film, unevenness on the surface of the base metal plate does not affect the appearance of the colored coating, but in the thin coating, the unevenness on the surface of the base metal plate has a large effect on the appearance of the colored coating. . That is, in a thin coating film, the gloss (gloss) on the surface of the colored coating film can be reduced by imparting a certain level of unevenness to the surface of the base metal plate, and scratches on the coating film can be made inconspicuous. Further, by providing a certain level of irregularities on the surface of the base metal plate, scratches are made only on the coating film portions on the convex portions, and the scratches are discontinuous and are not easily noticeable. In addition, the larger the distance between the convex portions on the surface of the base metal plate, the more easily the scratches on the coating film become discontinuous, and the scratches are less noticeable. Thus, the thinner the colored coating film is, the more conspicuous the effect is on the conspicuousness of the irregularities on the surface of the metal plate. On the other hand, the unevenness on the surface of the metal plate that forms the coating film also affects the corrosion resistance of the coated metal plate, suppresses the unevenness to below a certain level, and suppresses the spacing between the convexities to a certain level (reduces the frequency of the convexity). There is a need. This is because, particularly when the thickness of the colored coating film is thin and the unevenness of the surface of the base metal plate is large, the thickness of the coating portion on the convex portion of the base metal plate surface becomes extremely small, This is because barrier properties against corrosion factors such as oxygen are reduced. In addition, when the frequency of the convex portion is large, the frequency of the portion having poor barrier property is also increased. In other words, in order to improve the scratch resistance without reducing the corrosion resistance and workability of the chromate-free colored coated metal plate, especially the chromate-free colored painted metal plate with a thin coating film thickness, It is necessary to control the unevenness of the protrusions within a certain range and increase the distance between the protrusions by a certain amount or more. Further, when the frequency of the convex portions is too small, the gloss (gloss) on the surface of the colored coating film becomes high and scratches are easily noticeable. Therefore, it is necessary to increase the frequency of the convex portions above a certain level. Based on this, the inventors have repeatedly studied, and the inventors have determined that the surface roughness of the metal plate surface in the chromate-free colored coated metal plate of the present invention, that is, the arithmetic average roughness Ra is 0.7 to 1.5 μm. In addition, the requirement that the number of peaks PPI per inch (2.54 cm) in the average line direction of the roughness curve is 120 to 300 was found.

  In general, in a coated metal plate, the roughness of the surface of the metal plate does not significantly affect the workability, but affects the corrosion resistance and scratch resistance. In the chromate-free colored coated metal plate of the present invention, when the arithmetic average roughness Ra of the metal plate surface is less than 0.7 μm, the scratch resistance of the colored coated metal plate is liable to decrease, and when Ra exceeds 1.5 μm, Corrosion resistance tends to decrease. A more preferable range of Ra is 0.8 to 1.4 μm, and a more preferable range is 0.9 to 1.3 μm. When the number of peaks PPI per inch (2.54 cm) in the average line direction of the roughness curve exceeds 300, the scratch resistance and corrosion resistance of the colored coated metal plate are liable to decrease, and when it is less than 120, the colored coating The scratch resistance of the metal plate is likely to deteriorate (scratches are easily noticeable). The PPI is more preferably from 130 to 270, still more preferably from 140 to 250.

  In the present invention, the arithmetic average roughness Ra of the surface of the metal plate is measured by adopting a reference length of 0.8 mm in accordance with a measurement method defined in JIS B 0601 (1994). Ra can be measured using, for example, the Surfcom series of Tokyo Seimitsu Co., Ltd.

  The number of peaks per inch (2.54 cm) in the average direction of the roughness curve, PPI, is the Engineering Society for Advanced Mobility Land Air Air and Space: SAE J911-JUNME RED Measure according to the provisions of “SHEEET STEEL”. Referring to the roughness curve of the surface roughness relating to the definition of PPI defined in SAE J911-JUN 86 shown in FIG. 1, the predetermined evaluation length Ln is constant with respect to the average line of the roughness curve. The total number of counts when the reference level (cut level) H is provided and counted so as to be counted when the positive reference level is exceeded after exceeding the negative reference level is the PPI at the cut level H. In the present invention, the evaluation length Ln is the length of a 2.54 cm (1 inch) portion of the roughness curve perpendicular to the arbitrary plane direction of the metal plate, and the cut level H is 0.24 μm. For the measurement of PPI, for example, the Surfcom series of Tokyo Seimitsu Co., Ltd. can be used.

  The scratch resistance of the chromate-free colored coated metal plate of the present invention was evaluated by a pencil hardness test of the coating film. Specifically, in accordance with JIS K 5600-5-4, 5 lines were drawn with a pencil lead at a 45 ° angle on the coating film on the surface of the test plate, and after erasing the lines with an eraser, scratches were observed twice or more. The pencil hardness which does not enter was measured, and those having a pencil hardness of H or higher were evaluated as having no scratches, that is, good scratch resistance. The pencil was a uni-pencil manufactured by Mitsubishi Pencil Co., Ltd., and the test was performed under a load condition of 20 ° C. and 4.903 N (500 gf).

  The colored coating film (α) is a metal plate obtained by coating an aqueous coating composition (X) containing components of the coating film (organic resin (A), coloring pigment (B), and silica particles (C)) in an aqueous solvent. It is preferable to form by applying to at least one side of and drying by heating. Here, the aqueous solvent means that water is a solvent that is a main component of the solvent. The amount of water in the solvent of the present application is preferably 50% by mass or more. Solvents other than water contained in the aqueous solvent of the present application may be organic solvents, but those containing organic solvents as defined in the Occupational Safety and Health Act organic solvent poisoning prevention regulations (Attached Table 6-2 of the Ordinance for Enforcement of the Industrial Safety and Health Act) It is more preferable that the organic solvent listed in (1) exceeds 5% by weight). By using such an aqueous solvent, it is not necessary to pass an extra coating line for using the organic solvent-based paint, so that the manufacturing cost can be greatly reduced and the volatilization can be reduced. There is also a merit in terms of the environment, such as emission of volatile organic compounds (VOC) can be greatly suppressed.

  The thickness of the colored coating film (α) is 2 to 10 μm. The thickness of the colored coating film (α) is more preferably 3 to 7 μm. If it is less than 2 μm, sufficient designability (concealment), corrosion resistance, and scratch resistance may not be obtained. If it exceeds 10 μm, it is not only economically disadvantageous, but when the colored coating film (α) is formed from a water-based paint, coating film defects such as armpits may occur. The appearance required for the plate may not be obtained stably. Further, the colored coating film (α) in the present invention has a film thickness of 2 to 10 μm, the requirement for the roughness of the metal plate surface in the present invention, that is, the arithmetic average roughness Ra is 0.7 to 1.5 μm, and Excellent scratch resistance can be secured under the requirement that the number of peaks PPI per inch (2.54 cm) in the average line direction of the roughness curve is 120 to 300.

  The thickness of the colored coating film (α) can be measured by observing the section of the coating film or using an electromagnetic film thickness meter. In addition, the mass of the coating film adhered per unit area may be calculated by dividing by the specific gravity of the coating film or the specific gravity after drying of the coating solution. The adhesion mass of the coating is the mass difference before and after coating, the mass difference before and after peeling the coating after coating, or the presence of an element whose content in the coating is known in advance by fluorescent X-ray analysis. What is necessary is just to select appropriately from existing methods, such as measuring quantity. Specific gravity of the coating film or specific gravity after drying of the coating solution is measured by measuring the volume and mass of the isolated coating film, measuring the volume and mass after taking an appropriate amount of the coating solution in a container and drying, or coating film. What is necessary is just to select suitably from the existing method, such as calculating from the compounding quantity of a structural component, and the known specific gravity of each component.

  Among the various measuring methods described above, since coatings having different specific gravities and the like can be easily and accurately measured, it is preferable to use cross-sectional observation of the coating.

  The method for observing the cross section of the colored coating film (α) is not particularly limited, but after embedding a coated metal plate perpendicularly to the coating thickness direction in a room temperature drying type epoxy resin and mechanically polishing the embedded surface, SEM Using a method of observation with a scanning electron microscope or a FIB (focused ion beam) device, an observation sample having a thickness of 50 to 100 nm is cut out from the coated metal plate so that the vertical section of the coating film can be seen. A method of observing the cross section with a TEM (transmission electron microscope) can be suitably used.

  The essential components of the colored coating film (α) are the organic resin (A), the coloring pigment (B), and the silica particles (C). The organic resin is a film-forming component of the coating film and contributes to the development of scratch resistance, corrosion resistance, and workability of the chromate-free colored coated metal plate of the present invention. The color pigment is a component necessary for coloring the coating film, and imparts design properties to the chromate-free colored painted metal plate of the present invention. Silica particles are involved in improving the corrosion resistance and scratch resistance of the chromate-free colored coated metal sheet of the present invention.

  The organic resin (A) that is a film forming component of the colored coating film is not limited to a specific type, and examples thereof include polyester resins, polyurethane resins, epoxy resins, acrylic resins, polyolefin resins, and modified products thereof. be able to. Here, the modified product is a reactive functional group contained in the structure of these resins and reacts with “another compound” (such as a monomer or a crosslinking agent) containing a functional group capable of reacting with the functional group in the structure. It refers to the resin. The organic resin (A) may be used singly or in combination of two or more, and 1 organic resin obtained by modifying at least one other organic resin in the presence of at least one organic resin. You may use a seed | species or 2 or more types in mixture.

  Content of film-forming component of colored coating film (when organic resin (A) is not cured with curing agent (D) described later, content of organic resin (A) only, curing with organic resin (A) described later) When it is cured with the agent (D), the total amount of the organic resin (A) and the curing agent (D) is preferably 55 to 80% by mass in the coating film. If it is less than 55% by mass, the workability of the colored coated metal plate may be lowered, and if it exceeds 80% by mass, the scratch resistance of the colored coated metal plate may be lowered. A more preferable content of the film-forming component is 60 to 75% by mass.

  It is preferable that the organic resin (A) contains a polyester resin (Ae) containing a sulfonic acid group in the structure in order to achieve both high workability, corrosion resistance, and scratch resistance. Since the ester group contained in the structure of the polyester resin has an appropriate cohesive energy, the film physical properties (balance between elongation and strength) of the coating film can be enhanced in a high dimension. That is, applying a polyester resin as a film-forming component of a coating film is very effective in achieving both workability and scratch resistance at a high level. In addition, the sulfonic acid group contained in the polyester resin contributes to improving the adhesion to the metal plate (base treatment layer if there is a base treatment), which improves workability and scratch resistance. It is suitable. Further, when the coating composition for forming the coating film is aqueous, the sulfonic acid group has high hydrophilicity, so that the stability of the polyester resin in the aqueous coating composition is improved (coating composition). To prevent the solidification and the generation of aggregates). In particular, when a curing agent described later is used in combination, the pH fluctuation of the coating composition increases and the stability of the coating may decrease. However, when using a polyester resin containing a sulfonic acid group, the coating composition It is difficult to be affected by pH fluctuations and can suppress a decrease in paint stability. In addition, since the polyester resin containing a sulfonic acid group is difficult to dissolve in an organic solvent (is soluble only in some polar solvents), the resin is an organic solvent-based coating composition using an organic solvent as a solvent. It cannot be used practically with things. Moreover, when using a hardening | curing agent, it is common to use hardening catalysts, such as a sulfonic acid group containing compound, together, but there exists a possibility that such a hardening catalyst may reduce the corrosion resistance of a coating film. On the other hand, since the polyester resin containing a sulfonic acid group can be cured at low temperature without using a curing catalyst, it is not necessary to add a curing catalyst, and there is no concern about a decrease in corrosion resistance due to the addition of the curing catalyst. Therefore, since a polyester resin containing a sulfonic acid group cannot be applied to a paint using an organic solvent as a solvent, in the case of a coating film formed using this, the effects of the above sulfonic acid, particularly corrosion resistance and scratch resistance. We cannot expect the effect of having both sexes.

  It is preferable that content of the said polyester resin (Ae) is 60-100 mass% in the said organic resin (A). If it is less than 60% by mass, the effect of improving the workability, scratch resistance and corrosion resistance of the colored coated metal sheet may not be obtained. The more preferable content of the polyester resin (Ae) is 80 to 100% by mass.

  The polyester resin resin (Ae) preferably further includes a bisphenol structure in the structure. Since the bisphenol structure has high cohesive energy and excellent water resistance, it is preferable to include the bisphenol structure in order to improve scratch resistance and corrosion resistance.

  The polyester resin (Ae) is not particularly limited as long as it contains a sulfonic acid group in the structure. For example, it can be obtained by condensation polymerization of a polyester raw material comprising a polycarboxylic acid component and a polyol component. Moreover, it can also be made water-based by dissolving or dissolving the polyester resin obtained there in water.

  Examples of the polycarboxylic acid component include phthalic acid, phthalic anhydride, tetrahydrophthalic acid, tetrahydrophthalic anhydride, hexahydrophthalic acid, hexahydrophthalic anhydride, methyltetraphthalic acid, methyltetrahydrophthalic anhydride, hymic anhydride, Trimellitic acid, trimellitic anhydride, pyromellitic acid, pyromellitic anhydride, isophthalic acid, terephthalic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, adipic acid, azelaic acid, sebacic acid, succinic acid, anhydrous Examples thereof include succinic acid, lactic acid, dodecenyl succinic acid, dodecenyl succinic anhydride, cyclohexane-1,4-dicarboxylic acid, and anhydrous endo acid. As the polycarboxylic acid component, one type may be used, or a plurality of types may be used.

  Examples of the polyol component include ethylene glycol, diethylene glycol, 1,3-propanediol, 1,2-propanediol, triethylene glycol, 2-methyl-1,3-propanediol, and 2,2-dimethyl-1,3. -Propanediol, 2-butyl-2-ethyl-1,3-propanediol, 1,4-butanediol, 2-methyl-1,4-butanediol, 2-methyl-3-methyl-1,4-butane Diol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,2-cyclohexanedimethanol , Hydrogenated bisphenol-A, dimer diol, trimethylol ethane, trimethylol Propane, glycerin, and pentaerythritol and the like. As the polyol component, one kind may be used, or a plurality kinds may be used.

  The method for introducing the sulfonic acid group into the polyester resin is not particularly limited, and examples thereof include 5-sulfoisophthalic acid, 4-sulfonaphthalene-2,7-dicarboxylic acid, and 5- (4-sulfophenoxy) isophthalic acid. And dicarboxylic acids such as 2-sulfo-1,4-butanediol, 2,5-dimethyl-3-sulfo-2,5-hexyldiol and the like as a polyester raw material.

The sulfonic acid group refers to a functional group represented by —SO ₃ H, which may be neutralized with alkali metals, amines containing ammonia, or the like. In the case of neutralization, the already neutralized sulfonic acid group may be incorporated into the resin, or may be neutralized after the sulfonic acid group is incorporated into the resin. In particular, a sulfonic acid metal base neutralized with an alkali metal such as Li, Na, or K enhances the adhesion between the colored coating film and the metal plate of the base material, or is applied to a coating liquid for a coloring pigment having a hydrophobic surface. Is particularly preferable in terms of enhancing the dispersibility of sulfonic acid, and sodium sulfonate is more preferable.

  The amount of the dicarboxylic acid or glycol containing a sulfonic acid group used for introducing the sulfonic acid group is preferably 0.1 to 10 mol% with respect to the total polycarboxylic acid component or the total polyol component. . If it is less than 0.1 mol%, the effect of improving the adhesion between the colored coating film and the metal plate of the substrate may not be obtained, and when an aqueous solvent is used, the organic resin dissolves in water. The dispersibility of the color pigment may decrease, and the design of the formed colored coating film may decrease. If it exceeds 10 mol%, the corrosion resistance of the colored coated metal plate may be lowered. Considering the balance of performance, it is more preferably in the range of 0.5 to 7 mol%.

  The method for introducing the bisphenol structure is not particularly limited. For example, an ethylene oxide adduct of bisphenol A, a propylene oxide adduct of bisphenol A, an ethylene oxide adduct of bisphenol F, and a propylene oxide addition of bisphenol F The method of using glycols, such as a thing, as a polyester raw material is mentioned.

  It is preferable that the usage-amount of the glycol containing the said bisphenol structure is 1-40 mol% with respect to all the polyol components. If it is less than 1 mol%, the effect of improving scratch resistance and corrosion resistance of the colored coated metal sheet may not be obtained. If it exceeds 40 mol%, the workability of the colored coated metal plate may be lowered. Considering the balance of performance, it is more preferably in the range of 5 to 30 mol%.

  In the embodiment of the present invention in which the organic resin (A) contains the polyester resin (Ae), it further includes a polyurethane resin (Au) containing a urea group in the structure, thereby improving corrosion resistance and scratch resistance. This is particularly preferable. In order to achieve both workability, scratch resistance, and corrosion resistance, both the elongation and strength of the coating film are excellent, and the adhesion to the metal plate (base treatment layer if there is a base treatment) is increased. It is important, however, that a polyurethane resin (Au) containing a urea group having a very high cohesive energy is used in combination with the polyester resin (Ae), so that both the elongation and strength are excellent. It is possible to design a coating film with excellent adhesion to the material.

  When the polyurethane resin (Au) is included in the coating film (α) together with the polyester resin (Ae), the total content of the polyester resin (Ae) and the polyurethane resin (Au) is the organic resin (A). It is preferable that it is 60-100 mass% in inside, More preferably, it is 80-100 mass%. If it is less than 60% by mass, the effect of improving workability, scratch resistance, and corrosion resistance may not be obtained.

  Moreover, it is preferable that solid content mass ratio (Ae) / (Au) of the said polyester resin (Ae) and the said polyurethane resin (Au) is 25 / 75-90 / 10, 25 / 75-75 / 25 More preferably it is. If it is less than 25/75, the workability may be deteriorated, and if it exceeds 90/10, the effect of improving the corrosion resistance and scratch resistance may not be obtained.

  The polyurethane resin (Au) is not particularly limited as long as it contains a urea group in the structure. For example, the polyurethane resin (Au) is reacted with a polyol compound and a polyisocyanate compound and then further contains a chain extender containing an amino group. Examples thereof include those obtained by chain elongation.

  The polyol compound is not particularly limited as long as it is a compound containing two or more hydroxy groups per molecule. For example, polycarbonate polyol, polyester polyol, polyether polyol, polyesteramide polyol, acrylic polyol, polyurethane polyol, or A mixture thereof may be mentioned. The polyisocyanate compound is not particularly limited as long as it is a compound containing two or more isocyanate groups per molecule. For example, aliphatic isocyanate, alicyclic diisocyanate, aromatic diisocyanate, araliphatic diisocyanate, or those Of the mixture. The chain extender is not particularly limited as long as it is a compound containing one or more amino groups in the molecule. Ethylenediamine, propylenediamine, hexamethylenediamine, diethylenetriamine, dipropylenetriamine, triethylenetetramine, tetraethylenepenta Aliphatic polyamines such as min, aromatic polyamines such as tolylenediamine, xylylenediamine, diaminodiphenylmethane, alicyclic polyamines such as diaminocyclohexylmethane, piperazine, 2,5-dimethylpiperazine, isophoronediamine, hydrazine, Hydrazines such as succinic acid dihydrazide, adipic acid dihydrazide, phthalic acid dihydrazide, hydroxyethyldiethylenetriamine, 2-[(2-aminoethyl) amino] ethanol, 3-aminopropane Alkanolamines such as ol. These compounds can be used alone or in a mixture of two or more.

  The organic resin (A) is preferably an aqueous organic resin when the aqueous coating composition (X) containing an aqueous solvent is used for forming the coating film (α). The term “aqueous” as used herein means that when the organic resin (A) is dissolved or dispersed in water at a concentration of 1% by mass, after making an effort to make it uniform by heating or stirring, 25 It means that the solution or dispersion is uniform without causing precipitation of the resin when left at 24 [deg.] C. for 24 hours, and without any phase separation (like the upper layer / lower layer interface).

  The organic resin (A) is preferably a resin cured with a curing agent (D) in order to improve the scratch resistance and corrosion resistance of the colored coated metal plate. The curing agent (D) is not particularly limited as long as it can cure the organic resin (A), and examples thereof include a melamine resin and a polyisocyanate compound. The melamine resin is a resin obtained by etherifying a part or all of the methylol group of a product obtained by condensing melamine and formaldehyde with a lower alcohol such as methanol, ethanol, or butanol. It does not specifically limit as a polyisocyanate compound, For example, hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, tolylene diisocyanate etc. can be mentioned. A blocked product of a polyisocyanate compound may be used. For example, a blocked product of hexamethylene diisocyanate, a blocked product of isophorone diisocyanate, a blocked product of xylylene diisocyanate, a blocked product of tolylene diisocyanate, which is a blocked product of the polyisocyanate compound. Etc. A hardening | curing agent (D) may be used by 1 type, and may use 2 or more types together.

  It is preferable that the usage-amount of a hardening | curing agent (D) is 5-35 mass% with respect to 100 mass% of organic resin (A). If it is less than 5% by mass, the bake-hardening of the coating film is insufficient, and the corrosion resistance and scratch resistance of the colored coated metal plate may be lowered. If it exceeds 35% by mass, the bake-hardening of the coating film is excessive. Thus, the corrosion resistance and workability of the colored coated metal plate may be reduced.

  From the viewpoint of scratch resistance, the curing agent (D) preferably contains a melamine resin. It is preferable that content of a melamine resin is 30-100 mass% in a hardening | curing agent (D). If it is less than 30% by mass, the effect of improving scratch resistance may not be obtained.

  The organic resin (A) preferably further contains an acrylic resin. By containing the acrylic resin, the adhesion with the metal plate (base treatment layer when there is a base treatment) is improved, and the scratch resistance is improved. In addition, when the colored pigment (B) is a pigment having a hydrophobic surface such as carbon black (B1) described later, the colored coating film (α) formed by uniformly dispersing the pigment in an aqueous solvent. In addition, it is preferable to contain an acrylic resin in order to impart excellent design properties.

  The acrylic resin is not particularly limited, and for example, ethylenic unsaturated such as methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, etc. A single carboxylic acid alkyl ester monomer or a copolymer of two or more thereof, and further, an ethylenically unsaturated carboxylic acid monomer such as acrylic acid, methacrylic acid, maleic acid, itaconic acid; ethyl maleate, Monoester monomers of ethylenically unsaturated dicarboxylic acids such as butyl maleate, ethyl itaconate, butyl itaconate; (meth) acrylic acid-2-hydroxyethyl, (meth) acrylic acid-2-hydroxypropyl, (meta ) -4-hydroxybutyl acrylate, 2-hydroxyethyl (meth) acrylate and ε-caprola Hydroxyl group-containing ethylenically unsaturated carboxylic acid alkyl ester monomer such as a reaction product with Tn; ethylene such as aminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, butylaminoethyl (meth) acrylate Unsaturated carboxylic acid aminoalkyl ester monomers such as aminoethyl (meth) acrylamide, dimethylaminomethyl (meth) acrylamide, and ethylenically unsaturated carboxylic acid aminoalkylamide monomers such as methylaminopropyl (meth) acrylamide; acrylamide , Other amide group-containing ethylenically unsaturated carboxylic acid monomers such as methacrylamide, N-methylolacrylamide, methoxybutylacrylamide, diacetoneacrylamide; unsaturated fats such as glycidyl acrylate and glycidyl methacrylate Fatty acid glycidyl ester monomers; vinyl cyanide monomers such as (meth) acrylonitrile and α-chloroacrylonitrile; saturated aliphatic carboxylic acid vinyl ester monomers such as vinyl acetate and vinyl propionate; styrene, α- A styrene monomer such as methylstyrene or vinyltoluene may be used alone or in combination of two or more. The method for polymerizing these monomers is not particularly limited, and examples thereof include a method of radical polymerization of these monomers in an aqueous solution using a polymerization initiator. The polymerization initiator is not particularly limited, and for example, persulfates such as potassium persulfate and ammonium persulfate, and azo compounds such as azobiscyanovaleric acid and azobisisobutyronitrile can be used.

  It is preferable that content of the said acrylic resin is 0.5-20 mass% with respect to 100 mass% of said organic resins (A). If it is less than 0.5% by mass, the design properties (colorability, concealment) of the formed coating film may be reduced, and if it is more than 20% by mass, the corrosion resistance and workability of the coating film may be reduced. There is. A more preferable content of the acrylic resin is 1 to 15% by mass, and more preferably 2 to 10% by mass with respect to 100% by mass of the organic resin (A).

  The color pigment (B) contained in the colored coating film (α) in the chromate-free colored coated metal plate of the present invention is not limited to a specific type, and examples thereof include titanium dioxide, carbon black, graphite, iron oxide, and lead oxide. Colored inorganic pigments such as coal dust, talc, cadmium yellow, cadmium red, chrome yellow, phthalocyanine blue, phthalocyanine green, quinacridone, perylene, anthrapyrimidine, carbazole violet, anthrapyridine, azo orange, flavanthrone yellow, isoindoline yellow , Azo yellow, indanthrone blue, dibromanthanthrone red, perylene red, azo red, anthraquinone red, etc., organic powder, aluminum powder, alumina powder, bronze powder, copper powder, tin powder, Flour, phosphorus Katetsuko, metal coating mica powder, titanium coated mica powder dioxide, can be mentioned luminous material such as titanium dioxide-coated glass powder.

  When the coating film (α) is darkly colored, the color pigment (B) preferably contains carbon black (B1). Carbon black (B1) is not particularly limited, and known carbon blacks such as furnace black, ketjen black, acetylene black, channel black, and the like can be used. Further, carbon black subjected to known ozone treatment, plasma treatment, or liquid phase oxidation treatment can also be used. The particle size of the carbon black to be used is not particularly limited as long as there is no problem in dispersibility in the coating solution, coating film quality, and paintability. Specifically, a carbon black having a primary particle size of 10 to 120 nm is used. Is possible. In consideration of design and corrosion resistance in a thin film of about 2 to 10 μm, it is preferable to use fine carbon black having a primary particle diameter of 10 to 50 nm. When such carbon black is dispersed in an aqueous solvent, since aggregation occurs in the dispersion process, it is generally difficult to disperse with the primary particle size. That is, carbon black actually exists in the form of secondary particles having a particle size larger than the primary particle size in the coating solution, and also exists in the same form in the colored coating film (α) formed from the coating solution. . In order to ensure designability and corrosion resistance in the thin film, the particle size of the carbon black (B1) dispersed in the colored coating film (α) is important, and the average particle size is preferably 20 to 300 nm. .

  Carbon black (B1) has d ≦ 15, b ≦ 10, and d × b ≧ 20 when the content in the colored coating (α) is d mass% and the thickness of the colored coating (α) is b μm. It is preferable to satisfy. In order to ensure designability (concealment), it is important to secure a certain amount or more of the absolute amount of carbon black contained in the colored coating film (α). The absolute amount of carbon black can be expressed by the product of the carbon black content (d mass%) contained in the coating film and the coating film thickness (b μm). If d × b is less than 20, the designability (concealment) may be lowered. When d is more than 15, the film-forming property of the coating film is lowered, and the corrosion resistance and workability of the colored coated metal plate may be lowered.

  In the case where the colored coating film (α) is lightly colored, the color pigment (B) preferably contains titanium dioxide (B2). The particle diameter of titanium dioxide (B2) is preferably about 150 to 350 nm. If the thickness is less than 150 nm, aggregation of titanium dioxide particles in the aqueous coloring composition is likely to occur, and thus the designability (hiding property) after forming the colored coating film (α) may be reduced. , Designability (concealment) and workability may be reduced. A more preferable particle diameter of titanium dioxide (B2) is 200 to 300 nm. It is preferable that content in the colored coating film ((alpha)) of titanium dioxide (B2) is 10-70 mass%. If it is less than 10% by mass, the designability (hiding property) of the colored coating film may be lowered, and if it exceeds 70% by mass, the workability and corrosion resistance of the coated metal plate may be lowered. Generally, when the colored coating film (α) contains carbon black (B1) and is colored deeply, it is more coated than when it is not colored or lightly colored. The wound that has entered the film is characterized by being easily noticeable. Titanium dioxide (B2) has the effect of raising the scratch resistance of the coating film, and also has the effect of making the appearance close to light color and making the scratches inconspicuous. Therefore, in order to improve scratch resistance while ensuring designability (concealment), workability, and corrosion resistance with a thin colored coating film having a thickness of 10 μm or less as in the present invention, the colored coating film (α) It is preferable to contain both carbon black (B1) and titanium dioxide (B2). In this case, the carbon black (B1) and the titanium dioxide (B2) are preferably present in the coating film at a mass ratio of 0.5 / 9.5 to 3/7, and 1/9 to 2/8. More preferably, it exists in a mass ratio.

  The colored coating film (α) in the chromate-free colored coated metal plate of the present invention needs to contain silica particles (C) having an effect of improving the corrosion resistance and scratch resistance of the colored coated metal plate.

  The silica particles (C) are not particularly limited, and examples thereof include silica particles such as colloidal silica and fumed silica. Examples of commercially available products include Snowtex O, Snowtex N, Snowtex C, Snowtex IPA-ST (Nissan Chemical Industry), Adelite AT-20N, AT-20A (Asahi Denka Kogyo), Aerosil 200 (Nippon Aerosil) , Functional spherical silica HPS series (Toa Gosei), Nipsil series (Tosoh Silica) and the like.

  In the present invention, the colored coating film (α) preferably contains both spherical silica particles (C1) having an average particle diameter of 5 to 50 nm and spherical silica particles (C2) having an average particle diameter of 0.3 to 5 μm. . The “spherical shape” in the present invention refers to not only a true sphere but also a shape approximate to a sphere, and includes an ellipsoid. However, in the case of an ellipsoid, the ratio of the minor axis to the major axis is preferably 0.7 or more from the viewpoint of workability, corrosion resistance, and scratch resistance, and more preferably 0.8 or more. The spherical silica particles (C1) which are fine particles having an average particle diameter of 5 to 50 nm have a large effect of improving the corrosion resistance, and the spherical silica particles (C2) which are relatively large particles having an average particle diameter of 0.3 to 5 μm are scratch resistant. Great effect to improve adhesion. When the colored coating film (α) simultaneously contains particles having such different characteristics and different particle diameters, the corrosion resistance and scratch resistance of the colored coated metal plate are synergistically improved. The relatively large spherical silica particles (C2) having an average particle size of 0.3 to 5 μm also have the effect of degrading the gloss of the coated metal plate, so that even if there are some scratches on the colored coating film (α), it is conspicuous. It also has the advantage of becoming difficult. The average particle diameter of the spherical silica particles (C1) is less than 5 nm, which is technical from the viewpoint of particle stability (if lack of stability, problems such as aggregation of particles and gelation of the coating composition occur). When the average particle size is more than 50 nm, the effect of improving the corrosion resistance may be small. A more preferable range of the average particle diameter of the spherical silica particles (C1) is 8 to 30 nm. If the average particle diameter of the spherical silica particles (C2) is less than 0.3 μm, the effect of improving the scratch resistance of the coated metal plate may be small, and if it exceeds 5 μm, the workability and corrosion resistance may decrease. is there. Moreover, the dispersion stability in a coating composition may be inferior (sedimentation etc. arise). A more preferable range of the average particle diameter of the spherical silica particles (C2) is 0.5 to 3 μm.

  When the spherical silica particles (C1) and the spherical silica particles (C2) are used in combination as the silica particles (C), the content of the spherical silica particles (C1) is 3 to 30% by mass in the colored coating film (α). It is preferable. If it is less than 3% by mass, the effect of improving the corrosion resistance and scratch resistance of the coated metal plate may be inferior, and if it exceeds 30% by mass, the corrosion resistance and workability may be inferior. The more preferable content of the spherical silica particles (C1) is 5 to 20% by mass.

  The content of the spherical silica particles (C2) is preferably 3 to 20% by mass in the colored coating film (α). If it is less than 3% by mass, the effect of improving scratch resistance may be inferior, and if it exceeds 20% by mass, corrosion resistance and workability may be inferior. The more preferable content of the spherical silica particles (C2) is 5 to 15% by mass.

  As for content of the silica particle (C) in a colored coating film ((alpha)), 10-40 mass% is preferable. If it is less than 10% by mass, the effect of improving the satisfactory corrosion resistance and scratch resistance of the coated metal plate may not be obtained. If it exceeds 40% by mass, the corrosion resistance and workability may be lowered. The more preferable content of the silica particles (C) is 10 to 30% by mass.

  The content of the silica particles (C) applies also when the spherical silica particles (C1) and the spherical silica particles (C2) are used in combination. That is, the total content of the spherical silica particles (C1) and the spherical silica particles (C2) in the colored coating film is preferably 10 to 40% by mass, and more preferably 10 to 30% by mass. In this case, the content ratio of the spherical silica particles (C1) and the spherical silica particles (C2) in the coating film is preferably in the range of 30/70 to 80/20 by mass ratio, and 40/60 to 50/50. It is more preferable to be within the range. The ratio of the average particle diameter of the spherical silica particles (C1) and the spherical silica particles (C2) contained in the colored coating film (α) is preferably in the range of 1/350 to 1/16. More preferably, it is in the range of 1/150 to 1/30.

  The colored coating (α) of the colored coated metal plate of the present invention preferably further contains at least one resin particle (E) selected from an acrylic resin and a silicon resin. The resin particles (E) have the effect of improving the scratch resistance of the colored coated metal plate, the effect of reducing the gloss of the coating film, and making it less noticeable even if the coating film has some scratches.

  The type of acrylic resin is not particularly limited, and examples thereof include crosslinked polymethyl methacrylate, crosslinked polybutyl methacrylate, non-crosslinked polymethyl methacrylate, non-crosslinked polybutyl methacrylate, and polyalkyl acrylate. They can be copolymers with styrene. Cross-linked polymethyl methacrylate is particularly preferable in order to achieve both high scratch resistance and workability of the colored coated metal plate.

  The type of the silicone resin is not particularly limited, and examples thereof include dimethylpolysiloxane and polyorganosilsesquioxane. Polyorganosilsesquioxane is particularly preferable for achieving both high scratch resistance and workability of the colored coated metal plate.

  The average particle diameter of the resin particles (E) is not particularly limited, but the resin particles (E) are preferably dispersed as spherical particles having an average particle diameter of 1 to 5 μm in the colored coating film (α). If the average particle size is less than 1 μm, the effect of improving the scratch resistance of the colored coated metal sheet may not be obtained, and if the average particle size exceeds 5 μm, the dispersion stability in the coating solution is ensured. It may be difficult to cause problems such as sedimentation and solidification of particles. In addition, workability may also be reduced.

  When the average particle diameter of the resin particles (E) dispersed in the colored coating film (α) is c μm and the thickness of the coating film (α) is b μm, 0.3 ≦ c / b ≦ 1.2 is satisfied. It is preferable to do. If c / b is less than 0.3, the effect of improving the scratch resistance of the colored coated metal sheet may not be obtained, and if c / b is more than 1.2, the corrosion resistance and workability deteriorate. There is a case.

  The content of the resin particles (E) is preferably 0.5 to 15% by mass in the colored coating film (α). If it is less than 0.5% by mass, the effect of improving the scratch resistance of the colored coated metal sheet may not be obtained, and if it exceeds 15% by mass, the corrosion resistance and workability may be deteriorated. A more preferable content of the resin particles (E) is 1 to 10% by mass.

  It is preferable that the colored coating film ((alpha)) in the colored coating metal plate of this invention further contains a polyethylene resin particle (F). When the colored coating film (α) contains the polyethylene resin particles (F), the lubricity of the colored coating film is improved, and the scratch resistance of the colored coated metal plate is improved. The average particle diameter of the polyethylene resin particles (F) is not particularly limited, but the resin particles (F) are dispersed as spherical particles having an average particle diameter of 0.5 to 3 μm in the colored coating film (α). preferable. If the average particle size is less than 0.5 μm, the effect of improving the scratch resistance of the colored coated metal sheet may not be obtained, and if the average particle size is more than 3 μm, the corrosion resistance may be lowered.

  It is preferable that content of a polyethylene resin particle (F) is 0.5-10 mass% in a colored coating film ((alpha)). If it is less than 0.5% by mass, the effect of improving the scratch resistance of the colored coated metal sheet may not be obtained, and if it exceeds 10% by mass, the scratch resistance and corrosion resistance may be lowered. The more preferable content of the polyethylene resin particles (F) is 1 to 7% by mass.

  In the coating film (α) of the chromate-free colored coated metal plate of the present invention, the color pigment (B) and the silica particles (C) are present as particulate components. If necessary, one or both of resin particles (E) and polyethylene resin particles (F) may be present in addition to them.

  In general, it is extremely difficult to specify the shape and size of particles contained in a thin coating film. However, the particulate component contained in the coating material used to form the coating film (solution or dispersion (coloring composition) containing the constituent components of the coating film) Exists in paint even after film formation, unless it undergoes physical or chemical changes (eg, binding or agglomeration of particles, significant dissolution in paint solvent, reaction with other components) It can be considered that it retains the shape and size as it was. The color pigment (B), silica particles (C), resin particles (E), and polyethylene resin particles (F), which are particulate components used in the present invention, are aqueous solvents for paints used for forming the coating film of the present invention. It is chosen so that it does not dissolve significantly and does not react with solvents or other coating components. In addition, for the purpose of enhancing the retention of the existing form in the paint of these particulate components, if necessary, those dispersed in an aqueous solvent with a dispersant such as a known surfactant or water-soluble resin in advance. It can also be used as a raw material for paints. Therefore, the particle diameters of these particulate components contained in the coating film defined in the present invention can be expressed by their particle diameters in the paint used for forming the coating film.

  Specifically, the carbon black (B1) and titanium dioxide (B2) of the color pigment (B), such as silica particles (C1) having an average particle diameter of 5 to 50 nm among silica particles (C), The diameter of the fine particles can be measured by a dynamic light scattering method (nanotrack method). According to the dynamic scattering method, the diameter of fine particles in a dispersion medium having a known temperature, viscosity, and refractive index can be easily obtained. The particulate component used in the present invention is selected so that it does not significantly dissolve in the aqueous solvent of the paint and does not react with the solvent or other coating film components. It can be employed as the particle size of the particulate component in the paint. In the dynamic light scattering method, laser light is irradiated to fine particles that are dispersed in a dispersion medium and moving in brown, the scattered light from the particles is observed, the autocorrelation function is obtained by the photon correlation method, and the cumulant method is used. Measure the particle size. As a particle size measuring device by the dynamic light scattering method, for example, FPAR-1000 manufactured by Otsuka Electronics Co., Ltd. can be used. In the present invention, a dispersion sample containing the particles to be measured is measured at 25 ° C. to determine the cumulant average particle size, and the average value of five measurements in total is taken as the average particle size of the particles. The measurement of the average particle diameter by the dynamic light scattering method is described in, for example, Journal of Chemical Physics, Vol. 57, No. 11 (December, 1972), page 4814.

  On the other hand, as the diameter of relatively large particles such as silica particles (C2), resin particles (E), and polyethylene resin particles (F) having an average particle size of 0.3 to 5 μm among silica particles (C), The particle diameter at an integrated value of 50% in the particle size distribution measured by the laser diffraction / scattering method (microtrack method) can be adopted. The laser diffraction / scattering method is widely used to measure particle diameters from the submicron range to several millimeters by utilizing the fact that the amount of scattered light and the pattern scattered by the particle diameter vary depending on the particle size. It has been. Also in this case, the particulate component used in the present invention is selected so that it does not significantly dissolve in the aqueous solvent of the paint and does not react with the solvent or other coating film constituents. It can employ | adopt as a particle diameter of a particulate component. For measurement by the laser diffraction / scattering method, for example, a microtrack particle size analyzer manufactured by Nikkiso Co., Ltd. can be used. In the present invention, the average value of five measurements in total is taken as the average particle diameter of the particles.

  Further, at least one resin particle (E) selected from a particulate component (color pigment (B) as essential component, silica particle (C), optional component, acrylic resin, silicone resin) in the colored coating film (α). ) And polyethylene resin particles (F)), the colored coating film (α) can be observed from the cross section, and its shape and particle diameter can be directly measured. When the particles are not spherical, the major and minor diameters of the particles are measured, and the average value can be adopted as the particle diameter. The method for observing the cross section of the coating film (α) is not particularly limited, but after embedding a coated metal plate perpendicular to the thickness direction of the coating film in a room temperature drying type epoxy resin and mechanically polishing the embedded surface, SEM (scanning) Using an electron microscope) or a FIB (focused ion beam) apparatus, cut out a sample for observation having a thickness of 50 nm to 100 nm from a painted metal plate so that the vertical cross section of the coating film can be seen, A method of observing the film with a TEM (transmission electron microscope) can be suitably used.

  The chromate-free colored coated metal plate of the present invention preferably has a base treatment layer (β) under the colored coating film (α). The ground treatment layer (β) is not particularly limited, but by providing a ground treatment layer (β) containing at least one selected from a silane coupling agent, an organic resin, and a polyphenol compound, a colored coating film ( The adhesion between α) and the base metal plate can be further increased, and the corrosion resistance of the colored coated metal plate can be further increased. In addition, by providing a base treatment layer (β) containing all of the silane coupling agent, organic resin, and polyphenol compound, the adhesion between the colored coating film and the base metal plate is particularly enhanced, and the corrosion resistance of the colored coated metal plate is particularly improved. Can be increased.

  The silane coupling agent contained in the ground treatment layer (β) is not particularly limited. For example, it is sold by Shin-Etsu Chemical Co., Toray Dow Corning, Chisso, Momentive Performance Materials Japan, etc. Vinyltrimethoxysilane, vinyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropylethoxysilane, N- [2- (vinylbenzylamino) ethyl] -3-aminopropyltrimethoxysilane, γ- Methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxy Propylme Rudiethoxysilane, γ-glycidoxypropyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, N-β (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β- ( Aminoethyl) -γ-aminopropyltriethoxysilane, N-β- (aminoethyl) -γ-aminopropylmethyldimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, etc. Can be mentioned. A silane coupling agent may be used independently and may use 2 or more types together.

  The organic resin contained in the base treatment layer (β) is not particularly limited, and known organic resins such as a polyester resin, a polyurethane resin, an epoxy resin, a phenol resin, an acrylic resin, and a polyolefin resin can be used. In order to further enhance the adhesion between the colored coating film (α) and the base metal plate, it is preferable to use at least one of a polyester resin, a polyurethane resin, an epoxy resin, and a phenol resin. When the organic resin (A) contained in the colored coating film (α) is a polyester resin, in order to increase compatibility with the colored resin film and to increase the adhesion of the colored coating film to the base metal plate, The layer (β) particularly preferably contains a polyester resin.

  The polyphenol compound contained in the base treatment layer (β) refers to a compound having two or more phenolic hydroxyl groups bonded to a benzene ring, or a condensate thereof. Examples of the compound having two or more phenolic hydroxyl groups bonded to the benzene ring include gallic acid, pyrogallol, catechol and the like. The condensate of the compound having two or more phenolic hydroxyl groups bonded to the benzene ring is not particularly limited, and examples thereof include a polyphenol compound generally distributed in the plant kingdom called tannic acid.

  Tannic acid is a general term for aromatic compounds having a complex structure having a large number of phenolic hydroxyl groups widely distributed in the plant kingdom. The tannic acid used in the colored coating film of the present invention may be hydrolyzable tannic acid or condensed tannic acid. The tannic acid is not particularly limited, and examples thereof include hameli tannin, oyster tannin, chatannin, pentaploid tannin, gallic tannin, milovalan tannin, dibidi tannin, argarovira tannin, valonia tannin, catechin tannin and the like. . As the tannic acid, commercially available ones such as “tannic acid extract A”, “B tannic acid”, “N tannic acid”, “industrial tannic acid”, “purified tannic acid”, “Hi tannic acid”, “ "F tannic acid", "local tannic acid" (all manufactured by Dainippon Pharmaceutical Co., Ltd.), "tannic acid: AL" (manufactured by Fuji Chemical Industry Co., Ltd.) and the like can also be used.

  A polyphenol compound may be used by 1 type and may use 2 or more types together.

  The content of at least one selected from a silane coupling agent, an organic resin, and a polyphenol compound contained in the base treatment layer (β) is not particularly limited, but is preferably 10% by mass or more in the base treatment layer. When the content is less than 10% by mass, the content is small, and the effect of improving the adhesion of the colored coating film and the corrosion resistance of the colored coated metal sheet may not be obtained.

The adhesion amount of the base treatment layer (β) is not particularly limited, but is preferably in the range of 10 to 1000 mg / m ² . Is less than 10 mg / m ² can not be obtained a sufficient effect of surface treatment layer (beta), exceeds 1000 mg / m ² surface treatment layer (beta) is reduced adhesion to be substrate metal plate tends to cohesive failure There are things to do. From the viewpoint of stable effect and economy, a more preferable adhesion amount range is 50 to 500 mg / m ² .

  The base treatment layer (β) is formed by applying a coating agent for forming the base treatment layer (β) to at least one surface of the metal plate and drying by heating. Although there is no restriction | limiting in particular in the coating method of a coating agent, Well-known roll coating, spray coating, bar coating, immersion, electrostatic coating, etc. can be used suitably. There is no restriction | limiting in particular in the baking drying method, A metal plate may be heated previously, a metal plate may be heated after application | coating, or you may dry combining these. There is no restriction | limiting in particular in a heating method, A hot air, induction heating, near infrared rays, a direct fire, etc. can be used individually or in combination. About baking baking temperature, it is preferable that it is 60 to 150 degreeC by ultimate temperature. If the ultimate temperature is less than 60 ° C, drying may be insufficient, and the adhesion between the coating film and the base metal plate or the corrosion resistance of the colored coated metal plate may be reduced. Adhesiveness between the base metal plate and the base metal plate may be reduced. A more preferable ultimate temperature is 70 ° C to 130 ° C.

  As a metal plate applicable in the present invention, the surface on which the colored coating film (α) is formed has an arithmetic average roughness Ra of 0.7 to 1.5 μm, and the roughness curve has an average line direction. There is no particular limitation as long as the number of peaks PPI per inch (2.54 cm) satisfies the condition of 120 to 300, for example, iron, iron-base alloy, aluminum, aluminum-base alloy, copper, copper base A metal plate such as an alloy may be used, and a plated metal plate optionally plated on the metal plate may also be used. Among them, particularly suitable for application of the present invention are zinc-based plated steel sheets and aluminum-based plated steel sheets.

  Zinc-coated steel sheets include galvanized steel sheets, zinc-nickel plated steel sheets, zinc-iron plated steel sheets, zinc-chromium plated steel sheets, zinc-aluminum plated steel sheets, zinc-titanium plated steel sheets, zinc-magnesium plated steel sheets, zinc-manganese. Galvanized steel sheets such as plated steel sheets, zinc-aluminum-magnesium plated steel sheets, zinc-aluminum-magnesium-silicon-plated steel sheets, and cobalt, molybdenum, tungsten, nickel as a small amount of different metal elements or impurities in these plated layers Examples include those containing titanium, chromium, aluminum, manganese, iron, magnesium, lead, bismuth, antimony, tin, copper, cadmium, arsenic and the like, and those in which inorganic substances such as silica, alumina, and titania are dispersed.

  As the aluminum-based plated steel plate, a metal plate plated with aluminum or an alloy composed of aluminum and at least one of silicon, zinc, and magnesium, for example, an aluminum-silicon plated steel plate, an aluminum-zinc plated steel plate, and an aluminum-silicon-magnesium plated plate. A steel plate etc. are mentioned.

  Furthermore, the present invention can also be applied to a multi-layer plated metal plate in combination with the above plating and other types of plating such as iron plating, iron-phosphorus plating, nickel plating, cobalt plating and the like. The plating method is not particularly limited, and any known method such as an electroplating method, a hot dipping method, a vapor deposition plating method, a dispersion plating method, and a vacuum plating method may be used.

  Examples of the present invention will be described below. However, the present invention is not limited to these examples.

(1) Metal plate Table 1 shows the types of metal plates used, the arithmetic average roughness Ra, and the peak number PPI per 1 inch (2.54 cm) in length in the average line direction of the roughness curve. A mild steel plate having a thickness of 0.5 mm was used as the base material of the metal plate. The metal plate was used after subjecting the surface to alkaline degreasing treatment, washing with water and drying.

(2) Ground treatment layer The coating agent for forming the ground treatment layer is composed of an organic resin (Table 2), a silane coupling agent (Table 3), and a polyphenol compound (Table 4) in the blending amounts shown in Table 5. It was prepared by stirring using a paint disperser. The coating agent is applied to the surface of the metal plate prepared in the above (1) with a roll coater so as to have an adhesion amount of 100 mg / m ² , and dried under the condition of a reaching plate temperature of 70 ° C. Base treatment layers (E1 to E9) were formed.

(3) Coating Film The coating composition for forming the coating film is an organic resin (A) aqueous dispersion (the following Production Examples 1 to 5 and Table 6), a curing agent (D) (Table 7), and a color pigment. (B) (Table 8), silica particles (C) (Table 9), resin particles (E) (Table 10), polyethylene resin particles (F) (Table 11) are blended in the blending amounts shown in Tables 12-15. It was prepared by stirring using a paint disperser. In the production examples, “part” simply means mass part, and “%” means mass%. The above coating composition is applied to the upper layer of the base treatment layer formed in (2) (or a metal plate if there is no base treatment layer) with a roll coater so as to obtain a predetermined ultimate plate temperature. And dried to form a coating film.

<Water-based organic resin production example 1>
In a reaction vessel equipped with a stirrer, condenser and thermometer, 199 parts of terephthalic acid, 232 parts of isophthalic acid, 199 parts of adipic acid, 33 parts of 5-sodium sulfoisophthalic acid, 312 parts of ethylene glycol, 2,2-dimethyl-1,3 -125 parts of propanediol, 187 parts of 1,5-pentanediol and 0.41 part of tetrabutyl titanate were charged, and the esterification reaction was performed from 160 ° C to 230 ° C over 4 hours. Next, the pressure in the system was gradually reduced, the pressure was reduced to 5 mmHg over 20 minutes, and a polycondensation reaction was performed at 260 ° C. for 40 minutes under a vacuum of 0.3 mmHg or less. After adding 20 parts of butyl cellosolve and 42 parts of methyl ethyl ketone to 100 parts of the obtained copolyester resin, the mixture was stirred and dissolved at 80 ° C. for 2 hours, and further 213 g of ion-exchanged water was added to perform water dispersion. Thereafter, the solvent was distilled off while heating, followed by filtration through a 200 mesh nylon mesh to obtain a polyester resin aqueous dispersion (F1) having a solid content concentration of 30%.

<Water-based organic resin production example 2>
In a reaction vessel equipped with a stirrer, condenser and thermometer, 199 parts terephthalic acid, 266 parts isophthalic acid, 199 parts adipic acid, 312 parts ethylene glycol, 125 parts 2,2-dimethyl-1,3-propanediol, 1,5 -187 parts of pentanediol and 0.41 part of tetrabutyl titanate were charged, and the esterification reaction was carried out from 160 ° C to 230 ° C over 4 hours. Next, the pressure in the system was gradually reduced, the pressure was reduced to 5 mmHg over 20 minutes, and a polycondensation reaction was performed at 260 ° C. for 40 minutes under a vacuum of 0.3 mmHg or less. The mixture was cooled to 220 ° C. in a nitrogen stream, and 23 parts of trimellitic anhydride and 16 parts of ethylene glycol bisanhydrotrimellitate were added and reacted for 30 minutes. 100 parts of the obtained copolyester resin, 20 parts of butyl cellosolve and 42 parts of methyl ethyl ketone were added, and then stirred and dissolved at 80 ° C. for 2 hours. Then, 23 parts of isopropyl alcohol and 3.5 parts of triethylamine were added, and 213 parts of ions Water dispersion was performed with exchange water. Thereafter, the solvent was distilled off while heating, followed by filtration through a 200 mesh nylon mesh to obtain a polyester resin aqueous dispersion (F2) having a solid content concentration of 30%.

<Water-based organic resin production example 3>
In a reaction vessel equipped with a stirrer, condenser and thermometer, 199 parts terephthalic acid, 232 parts isophthalic acid, 199 parts adipic acid, 33 parts 5-sodium sulfoisophthalic acid, 250 parts ethylene glycol, 2,2-dimethyl-1,3 -Propanediol 125 parts, 1,5-pentanediol 187 parts, bisphenol A ethylene oxide adduct 62 parts, tetrabutyl titanate 0.41 part were charged, and esterification was performed from 160 ° C to 230 ° C over 4 hours. . Next, the pressure in the system was gradually reduced, the pressure was reduced to 5 mmHg over 20 minutes, and a polycondensation reaction was performed at 260 ° C. for 40 minutes under a vacuum of 0.3 mmHg or less. After adding 20 parts of butyl cellosolve and 42 parts of methyl ethyl ketone to 100 parts of the obtained copolyester resin, the mixture was stirred and dissolved at 80 ° C. for 2 hours, and further 213 g of ion-exchanged water was added to perform water dispersion. Thereafter, the solvent was distilled off while heating, followed by filtration through a 200 mesh nylon mesh to obtain a polyester resin aqueous dispersion (F3) having a solid content concentration of 30%.

<Water-based organic resin production example 4>
Add 230 parts of a polyether polyol of average molecular weight 900 synthesized from tetramethylene glycol and ethylene glycol and 15 parts of 2,2-bis (hydroxymethyl) propionic acid to 100 parts of N-methyl 2-pyrrolidone and warm to 80 ° C. And dissolved. Thereafter, 100 parts of hexamethylene diisocyanate was added, heated to 110 ° C. and reacted for 2 hours, and 11 parts of triethylamine was added for neutralization. This solution was dropped into an aqueous solution in which 5 parts of ethylenediamine and 570 parts of ion-exchanged water were mixed with strong stirring to obtain a polyurethane resin aqueous dispersion (F4) having a solid content concentration of 30%.

<Water-based organic resin production example 5>
80 parts of a polyether polyol having an average molecular weight of 900 synthesized from tetramethylene glycol and ethylene glycol, 120 parts of a 3 mol adduct of bisphenol A propylene oxide having an average molecular weight of 700, and 12 parts of 2,2-bis (hydroxymethyl) propionic acid In addition to 100 parts of N-methyl 2-pyrrolidone, it was heated to 80 ° C. and dissolved. Thereafter, 100 parts of hexamethylene diisocyanate was added, heated to 110 ° C. and reacted for 2 hours, and 11 parts of triethylamine was added for neutralization. This solution was dropped into an aqueous solution obtained by mixing 5 parts of ethylenediamine and 570 parts of ion-exchanged water under strong stirring to obtain a polyurethane resin aqueous dispersion (F5) having a solid content concentration of 30%.

(4) Painted metal plate Tables 13 to 16 show the coating film configuration, the film thickness of the coating film, and the ultimate plate temperature of the coated metal plate produced in (1) to (3) above.

(5) Evaluation test About the coating metal plate (test plate) obtained by said (4), workability, corrosion resistance, and damage resistance were evaluated by the evaluation method and evaluation criteria shown below. The evaluation results are shown in Tables 16-19.

(Processability)
The test plate was subjected to 180 ° bending, and the outer appearance of the bent portion was evaluated according to the following evaluation criteria. The bending process was performed in an atmosphere of 20 ° C. with a 0.5 mm spacer in between (generally referred to as 1T bending).
5: The coating has no defects such as cracks and has a uniform colored appearance. No discoloration is observed.
4: Since slight cracks are observed in the coating film, a slight color fading is observed, but the appearance is almost uniform (a level that can be understood by arranging the test plates before the test side by side).
3: Slight cracking is observed because a slight crack is observed in the coating film, but the color appearance is almost uniform (a level that can be easily understood when the test plates before the test are arranged side by side).
2: Cracks are observed in the coating film, and color fading is observed (a level that can be understood by looking at only the test plate).
1: Cracks were observed in the coating film, and color fading was remarkable (a level that can be easily seen by looking at only the test plate).

(Corrosion resistance)
After the end surface of the test plate was tape-sealed, a salt spray test (SST) based on JIS Z 2371 was performed for 72 hours, the state of rust generation was observed, and evaluated according to the following evaluation criteria.
5: No rust generation.
4: Rust generation area is less than 1%.
3: Rust generation area is 1% or more and less than 2.5%.
2: Rust generation area is 2.5% or more and less than 5%.
1: Rust generation area is 5% or more.

(Scratch resistance)
In accordance with JIS K 5600-5-4, after drawing 5 lines with a pencil lead at a 45 ° angle on the coating film on the surface of the test plate and erasing the line with an eraser, the pencil hardness is not damaged more than twice. It was measured. When the pencil hardness was H or more, it was evaluated that the scratches were not noticeable, that is, the scratch resistance was good. The pencil was a uni-pencil manufactured by Mitsubishi Pencil Co., Ltd., and the test was performed under a load condition of 20 ° C. and 4.903 N (500 gf).

  The examples of the present invention exhibited excellent workability of 3 points or more, corrosion resistance, and excellent scratch resistance of pencil hardness H or higher in any evaluation test. Moreover, it was confirmed by visual observation that all of the examples were excellent in design properties (colorability including processed parts, hiding properties). In addition, when the coating composition used for the Example of this invention was left still at 40 degreeC for 1 month and the storage stability was investigated, the coating composition used in Example 33 was gelatinized. That is, the storage stability of the polyurethane resin F6 containing a cationic functional group is slightly unstable as compared with other coating compositions. Further, precipitates were generated in the coating compositions used in Examples 69 and 74. That is, those using relatively large spherical silica particles with a particle size of 6.8 μm for silica particles (C) and those using relatively large resin particles with a particle size of 8 μm for resin particles (E) are silica particles or Sedimentation of the resin particles occurred, and their dispersion stability was slightly inferior to those of other coating compositions. However, the workability, corrosion resistance, and scratch resistance of the coating films of Examples 33, 69, and 74 were all good.

  On the other hand, Comparative Examples 1 to 9 in which at least one of the arithmetic average roughness Ra and the number of peaks PPI per 1 inch (2.54 cm) in length in the average line direction of the roughness curve is out of the scope of the present invention are corrosion resistance and scratch resistance. Either or both of the adherence were inferior. The comparative example 10 which does not contain a silica particle (C) was inferior in corrosion resistance and scratch resistance. In Comparative Example 11 in which the film thickness of the colored coating film was less than 2 μm, the corrosion resistance and scratch resistance were also inferior.

  As mentioned above, although preferred embodiment of this invention was described, it cannot be overemphasized that this invention is not limited to this example. It will be apparent to those skilled in the art that various changes and modifications can be envisaged within the scope of the claims, and these are naturally within the technical scope of the invention. Is done.

Claims (14)

A chromate-free colored coating metal in which a colored coating film (α) comprising an organic resin (A) as a film-forming component and containing a color pigment (B) and silica particles (C) is formed on at least one surface of a metal plate. A board,
The roughness of the surface of the metal plate is 0.7 to 1.5 μm in arithmetic mean roughness Ra, and 120 to 120 in peak number PPI per 1 inch (2.54 cm) length in the average line direction of the roughness curve. 300,
The chromate-free colored painted metal plate, wherein the colored coating film (α) has a thickness of 2 to 10 μm.   The chromate-free colored coated metal plate according to claim 1, wherein the organic resin (A) is a resin cured with a curing agent (D).   The silica particle (C) contains spherical silica particles (C1) having an average particle diameter of 5 to 50 nm and spherical silica particles (C2) having an average particle diameter of 0.3 to 5 µm. Or a chromate-free colored painted metal plate according to 2;   The said colored coating film ((alpha)) further contains the at least 1 sort (s) of resin particle (E) chosen from an acrylic resin and a silicone resin, The one of Claims 1-3 characterized by the above-mentioned. Chromate-free colored painted metal plate.   The chromate-free colored painted metal sheet according to claim 4, wherein the resin particles (E) have an average particle diameter of 1 to 5 µm.   The chromate-free colored coated metal plate according to any one of claims 1 to 5, wherein the colored pigment (B) contains carbon black (B1).   The chromate-free colored coated metal sheet according to any one of claims 1 to 6, wherein the color pigment (B) contains titanium dioxide (B2).   The said organic resin (A) contains the polyester resin (Ae) which contains a sulfonic acid group in a structure, The chromate-free coloring coating metal plate of any one of Claims 1-7 characterized by the above-mentioned.   The chromate-free colored painted metal sheet according to claim 8, wherein the polyester resin (Ae) further contains a bisphenol structure in the structure.   The chromate-free colored coated metal plate according to claim 8 or 9, wherein the organic resin (A) further contains a polyurethane resin (Au) having a urea group in its structure.   The chromate-free colored coated metal plate according to any one of claims 1 to 10, wherein the colored coating film (α) further contains polyethylene resin particles (F).   The chromate-free colored coated metal sheet according to claim 11, wherein the polyethylene resin particles (F) have an average particle diameter of 0.5 to 3 µm.   The chromate-free colored coated metal plate according to any one of claims 1 to 12, wherein the chromate-free colored coated metal sheet has a base treatment layer (β) below the colored coating film (α).   The said coating film ((alpha)) of Claims 1-13 forms by apply | coating and heat-drying the water-system coating composition (X) containing the structural component of the said coating film ((alpha)) to the at least single side | surface of a metal plate. The chromate-free colored coated metal sheet according to any one of claims 1 to 13, wherein the metal sheet is coated with a chromate-free material.

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