JP2006212777A - Pattern coated metal sheet excellent in design properties and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pattern coated metal sheet excellent in design properties capable of imparting the sharp impression of a pattern without making the pattern too regular, and its manufacturing method. <P>SOLUTION: The pattern coated metal sheet is constituted by successively providing a ground coating film 4, a topcoating film 5 and a pattern coating film having a hue different from the hues of both of the ground coating film and the topcoating film at least on one side of a metal sheet to which substrate treatment is applied. The ground coating film covers the whole surface of the substrate treatment layer and the topcoating film covers a part of the ground coating film. The pattern coating film 6-1 on the ground coating film and the pattern coating film 6-2 on the topcoating film are respectively present on the ground coating film and the topcoating film in an island state. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a pattern-coated metal plate excellent in design and suitable for use in home appliances, indoor and outdoor building materials, and the like, and a method for producing the same.

  In a product using a metal plate, the outer plate touched by human eyes is mostly used with some coating applied for the purpose of improving the corrosion resistance and the design.

  Conventionally, such painting has been performed by an after-coating method in which painting is performed after completion of product assembly, but recently, the use of pre-painted metal sheets (pre-coated metal sheets) has been increasing.

  The percentage of use of coated metal plates is increasing: (1) can help customers skip processes, (2) can avoid complicated tasks such as degreasing and painting, (3) in urban areas In the case of home appliance factories that are located, it is difficult to renew the paint factory, (4) special functions can be added, and (5) design characteristics can be added.

  Among these reasons, a pattern-coated metal plate has been demanded particularly focusing on the design properties of the painted metal plate.

  The following are known as prior arts for pattern-coated metal plates.

  Patent Document 1 describes a multicolor pattern coating facility and a multicolor pattern coating method capable of forming a uniform multicolor pattern coating film by spray coating even in high-speed coating such as coil coating. The equipment is a painting equipment for spraying two or more colors of paint on a belt-like object moving at a speed of 10 m / min or more to form a multi-colored paint film. A plurality of spray coating machines having at least one are fixed to a coating machine support, and each paint discharge nozzle is arranged facing the surface of the object to be coated, and at least two paint discharge nozzles of each spray coating machine are different from each other. Coating device for discharging color paint, paint supply device for supplying two or more colors of paint stored in separate tanks to each paint discharge nozzle of each spray coating machine via a pump, and paint generated at the time of spray coating It is a multi-pattern coating facility characterized by comprising a local exhaust device that captures dust. A multicolor pattern coating method is described in which a multicolor paint film is formed by spray painting two or more colors of paints using this multicolor pattern paint facility.

  Patent Document 2 describes a painted metal plate with a hammer tone pattern. Hammer-tone pattern painting is applied to the varnish as a paint with inorganic pigment powder, for example, metal powder such as aluminum powder, gold powder, stainless steel powder, non-metal powder such as par powder, and other colors as required. A small amount of the above pigment is blended, and a shade is produced depending on the thickness of the coating film. By forming a concavo-convex pattern on the coating film that is struck with a hammer during coating, It is designed to produce shades of color.

  The hammer-tone pattern coated metal plate described in Patent Document 2 is obtained by applying an undercoating paint on the surface of the metal plate and drying it, and then applying an intermediate coating containing inorganic pigment powder on the surface of the metal plate. Is a resin-based paint that is compatible before drying, sprays the top coat paint with a surface tension smaller than that of the mid coat paint, forms an irregular pattern, and then dries it. It is obtained by setting the wet coating thickness to 25 μm or more.

JP 2003-135998 A JP-A-8-216331

  However, the pattern-coated metal plates according to these conventional techniques have a problem in that the sizes and colors of the patterns are not uniform and the patterns are unclear, resulting in poor design.

  The pattern-painted metal plate described in Patent Document 1 has a pattern that can be enlarged depending on the conditions, so the pattern looks clear, but because it is spray-coated, the size of the paint grains does not become constant, so the irregularity of the pattern is noticeable. Inferior in design.

  Also, the hammer-tone-patterned metal plate described in Patent Document 2 is coated with a primer coating on the surface of the metal plate and cured, and then overcoated with a coating containing inorganic pigment powder to form a ground coating film. In addition, it is manufactured by spray coating a paint with low surface tension on it to form a pattern, but the pattern is a single color and the pattern size is small under thin film conditions where cracks are unlikely to occur. Since it becomes unclear, it is inferior in design property.

  In addition, there is a pattern printing metal plate similar to the pattern coating metal plate, which transfers ink containing a pigment in a high concentration exceeding 60% by mass to a metal plate having a dried ground coating film. The pattern is developed by printing. However, in this pattern printed metal plate, the transferred pattern is repeatedly printed on the metal plate, and the pattern is regular, so it may give an artificial impression.

  The present invention avoids a pattern having perfect regularity that gives an artificial impression like a pattern-printed metal plate, and is an island-like pattern painted at random, It is an object of the present invention to provide a pattern-coated metal plate that is excellent in design and can give an impression that it is a clear pattern without causing irregularities.

  As a result of various studies on the irregular feeling of the randomly-patterned island pattern and the unclearness of the pattern, the present inventor has obtained the following findings (i) to (iii).

  (i) The impression of the pattern varies depending on the pattern size of the island pattern coating film formed by spray painting on the ground coating film. When the pattern size of the island pattern coating film is large, the pattern looks clearer, but the irregularity of the pattern becomes more conspicuous. On the contrary, when the pattern size is small, the irregularity of the pattern becomes inconspicuous, but the pattern itself gives an unclear impression.

  (ii) When the pattern size of the island-shaped pattern coating film is large or small, the large pattern is dominant in the impression, but only the large pattern becomes monotonous and inferior in design. When the large pattern and the small pattern are appropriately distributed, the design is not monotonous and the design is improved.

  (iii) On the ground coating, spraying paints with different hues by spraying multiple times or using multiple nozzles, a multi-island pattern coating with different hues in islands. Can be formed. The island-like pattern looks clearer in the polyphase than in the single phase, but the irregularity of the pattern is conspicuous. In addition, when attempting to form a multi-phase island pattern, multiple spray coatings or multiple nozzle coatings are required, which increases equipment and operating costs and may increase coating costs. .

  The present inventors have obtained the following ideas (a) to (g) as a method for solving these problems all at once.

  (a) Instead of spraying the pattern paint directly on the ground paint film, the top paint film is applied on the ground paint film so as to cover a part of the ground paint film, and then the ground paint and the top paint are applied. If a pattern-forming paint with a different hue is spray-coated in an island shape, the pattern-painted metal is a mixture of an island-shaped pattern paint painted on the ground paint and an island-shaped paint painted on the top coat. Board can be provided.

  (b) At this time, after baking the ground coating film, the top coating film is applied so as to cover a part of the ground coating film, and the pattern coating paint is spray-coated in an island shape while the top coating film is undried. After that, the top coating and the pattern forming coating can be baked and cured. When the top coat film is undried and the paint on the pattern coat is spray-coated on the island, the pattern paint on the top coat spreads over the top coat because of its high fluidity, An island-like pattern having a large pattern size with a flat surface is formed and is in close contact with the top coat film. On the other hand, since the ground coating has been baked and cured, the pattern paint sprayed in the shape of islands on the ground coating has low fluidity, so a convex island pattern with a small pattern size. Is formed. Therefore, a pattern-coated metal plate in which a large pattern and a small pattern are appropriately distributed can be provided by a single spray coating, and the island-shaped pattern can also have a three-dimensionally different shape. Therefore, it is not monotonous and the design is improved.

  (c) Furthermore, when the hues of the ground coating film and the top coating film are changed, the island pattern formed on the ground coating film and the island pattern formed on the top coating film are Different hues can give a different impression. For this reason, even if the hue of the pattern paint is the same, it is possible to provide a pattern-coated metal plate that gives various impressions. Of course, if a pattern paint having a different hue is used, it is possible to provide a pattern-coated metal plate that gives more various impressions.

  (d) When the pattern size is large or small, the large pattern is dominant in the impression. Therefore, it is preferable to set the maximum pattern size in the island pattern coating film within a specific range.

  (e) The impression of the pattern varies depending on the ratio of the island pattern coating film to the entire coating surface, that is, the area ratio of the island pattern coating film. Therefore, it is preferable to set the area ratio of the island pattern coating film within a specific range.

  (f) The impression of the pattern varies depending on the area ratio of the top coat film to the ground coat film, but various area ratios can be examined in consideration of the difference in hue between the ground coat film and the top coat film. preferable.

  (g) When the hue difference of the island pattern coating film is large with respect to the hue of the ground coating film or the top coating film, the pattern looks clear but the pattern irregularity becomes conspicuous. However, since the difference in hue between the ground coating and the top coating also affects, the difference in the impression when the hue of the ground coating and the top coating is the same, and the impression when the hue is different. It is preferable to consider including differences.

  The present invention has been completed based on the above findings (i) to (iii) and the ideas of (a) to (g), and is a pattern-coated metal plate (A) having excellent design properties according to the present invention. And its manufacturing method (B) has the following characteristics, respectively.

(A) Pattern-coated metal plate having excellent design properties according to the present invention:
A coated metal plate having a ground coating film, a top coating film, and a ground coating film and a pattern coating film having a hue different from that of the ground coating film on at least one side of the ground metal plate, A design characterized in that it covers the entire surface of the ground treatment layer, the top coating film covers a part of the ground coating film, and the pattern coating film exists in an island shape on the ground coating film and / or the top coating film. Pattern coated metal plate with excellent properties.

  In addition, it is preferable to form an undercoat coating film under the ground coating film. It is preferable that the maximum pattern diameter in the pattern coating existing in an island shape on the ground coating is 1.5 to 3 mm, and the ground coating of the pattern coating existing in an island shape on the ground coating. It is preferable that the area ratio with respect to is 20 to 80%. It is preferable that the maximum pattern diameter in the pattern coating film existing in an island shape on the top coating film is 3.5 to 6 mm, and the top coating film of the pattern coating film existing in an island shape on the top coating film It is preferable that the area ratio with respect to is 20 to 80%.

(B) A method for producing a pattern-coated metal sheet having excellent design properties according to the present invention:
After applying the ground treatment to at least one surface of the metal plate, the ground coating is applied to the entire surface of the ground treatment layer and baked, and then the top coating film is applied so as to cover a part of the ground coating film. A pattern-coated metal sheet with excellent design characteristics, characterized in that one or more types of pattern-forming paints with different hues from top-coating paints are spray-coated in an island shape and then the top-coating paints and pattern-forming paints are baked and cured. Production method.

  In addition, although an undercoat may be applied before the grant coating is applied, it is preferable to apply the grant coat after baking the undercoat.

  According to the present invention, it is possible to provide a pattern-coated metal plate excellent in design and capable of giving an impression of a clear pattern without being too regular, and a method for producing the same.

  Below, the pattern coating metal plate excellent in the designability of this invention and its manufacturing method are demonstrated.

(1) Metal plate that is the base material of the painted metal plate:
The metal plate that is the base material of the painted metal plate is not particularly limited, and examples thereof include a cold-rolled steel plate, a stainless steel plate, and an aluminum plate.

  In the case of a coated metal plate used for indoor and outdoor building materials and for home appliances, a zinc-based or aluminum-based plated steel plate is preferable in terms of corrosion resistance and economy.

  The plated metal plate may be plated by any method such as hot dipping, electroplating, vapor phase plating, etc., and zinc, tin, aluminum, etc. and alloys thereof are used as the plating metal species. Specifically, a hot-dip galvanized metal plate, a hot-dip Zn—Al alloy-plated metal plate containing 5% Al, a hot-dip aluminum-plated metal plate, a hot-dip Al—Zn alloy-plated metal plate containing 55% Al, and the like can be mentioned. .

(2) About ground treatment:
As for the metal plate used as the base material of a coating metal plate, in order to improve the adhesiveness of a base metal plate and a coating film, a surface treatment is given to the metal plate surface.

  The ground treatment is performed by chemical conversion treatment such as zinc phosphate treatment and chromate treatment. As the chromate treatment, electrolytic or reactive chromate treatment can also be applied, but coating chromate treatment is preferable from the viewpoint of workability. The chromate adhesion amount in terms of metal chromium is preferably in the range of 20 to 80 mg / m2. If the amount of chromate attached is too small, sufficient adhesion of the coating film cannot be obtained, and if it is excessive, workability will be reduced. One example of a commercially available coating-type chromate treatment solution suitable for use in the present invention is “NRC 300” manufactured by Nippon Paint Co., Ltd. The coating type chromate treatment liquid may be applied by a roll coater or the like according to a conventional method, heated to 50 to 100 ° C. with hot air and dried to carry out the ground treatment.

If it is not desired to perform chromate treatment using hexavalent chromium due to environmental problems, a chromium-free ground treatment containing silica, resin, zirconium or titanium can be performed. One example suitable for use in the present invention is “Surfcoat EC2000” manufactured by Nippon Paint Co., Ltd., which is a silica-based surface treatment solution.
(3) About the undercoat film:
A ground coating may be formed directly after applying a surface treatment to the metal plate surface, but depending on the application, especially when corrosion resistance is required, an undercoat coating may be formed under the ground coating. It is preferable to leave.

  For example, epoxy-based, polyester-based, and urethane-based resins can be used as the paint for the undercoat coated on the metal plate serving as the base of the coated metal plate. A resin capable of forming a coating film having excellent adhesion to the metal plate and good workability is preferable. The solvent of the paint used may be either an aqueous or organic solvent, or may be a powder paint that does not use a solvent.

  Various types of epoxy paints are commercially available, and these may be used as appropriate. For example, an epoxy paint containing melamine, amine, or isocyanate as a crosslinking agent may be used. As the epoxy resin type, a bisphenol type epoxy resin is preferable.

  As an example of a polyester-type coating material, what mix | blended melamine and isocyanate as a crosslinking agent with the thermoplastic polyester resin is mentioned. As the polyester, a so-called high molecular weight polyester resin having a molecular weight of about 5,000 to 20,000 is preferable from the viewpoint of processability. As the crosslinking agent, melamine modified with ethyl alcohol or butyl alcohol can be used, and in some cases, paratoluenesulfonic acid, dodecylbenzenesulfonic acid, or the like can be appropriately used as a catalyst.

  Examples of urethane-based paints include those in which a polyester polyol is subjected to a crosslinking reaction with a yellowing polyisocyanate or a non-yellowing polyisocyanate. As examples of the crosslinking agent, isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HMDI) and the like can be used. In this case also, a catalyst such as dibutyltin dilaurate (DBTL) may be used as appropriate.

  The paint for the undercoat film may contain two or more kinds of resin. The undercoating film may be a single layer, but may be two or more layers depending on the application. The undercoat coating film may contain additives such as rust preventive pigments. Examples of the rust preventive pigment include chromium-based rust preventive pigments such as strontium chromate and zinc chromate, and phosphate-based rust preventive pigments.

  The thickness of the undercoat coating film is preferably about 1 to 15 μm as a dry film thickness. The corrosion resistance is good when the coating thickness is 1 μm or more, but when the coating thickness exceeds 15 μm, the corrosion resistance is saturated and the cost only increases. Moreover, workability is favorable when the coating film thickness is 15 μm or less. A preferable coating film thickness is 3 to 10 μm.

  The paint for the undercoat film is applied onto a metal plate that has undergone a base treatment using an appropriate coating device such as a roll coater. The coating may be performed not only by coating but also by electrostatic coating or electrodeposition coating using a spray coater.

  The viscosity of the paint is adjusted to 30 to 150 seconds with Ford Cup # 4, and after painting, it is heated and baked. The baking can be performed by baking for about 20 to 60 seconds so that the maximum temperature of the metal plate is about 150 to 230 ° C., and a conventional hot air blowing type oven or a heating method such as induction heating or infrared heating can be used. Available.

  The undercoat coating film may be baked simultaneously with the baking of the ground coating film or before the coating of the ground coating film is applied.

(4) About ground coating:
The ground coating film is a coating film that serves as a base on which the pattern coating film is applied. The ground coating is applied directly or via a coating film of an undercoat paint after the base treatment. The coating of the ground coating can be appropriately selected according to the part of the product where the coated metal plate is used, and has excellent adhesion with the base treatment film or the undercoat, It is preferable to use a paint having excellent adhesion between the top coat film and the pattern paint film.

  As the resin type used for the ground paint, in addition to the resin type described above for the undercoat paint, a fluorine-based resin can also be used. When weather resistance and workability are required, polyester-based, urethane-based and fluorine-based resins are preferable. Specific embodiments of the epoxy-type, polyester-type and urethane-type resin types are the same as those described in the above (3) Undercoat film.

  Examples of the fluororesin paint include a mixture of an acrylic resin and PVdF (polyvinylidene fluoride). A mass ratio of 50:50 to 10:90 is preferred. The fluorine-based resin paint is particularly suitable for applications requiring weather resistance.

  The solvent of the paint used may be either an aqueous or organic solvent, or may be a powder paint that does not use a solvent.

  The coating material for the ground coating film may contain two or more kinds of resin. The ground coating film may be one layer, but may be two or more layers depending on the application. Since the ground coating film is a coating film that serves as a base for randomly painting the island-shaped pattern coating film, a color pigment can be included as necessary in relation to the hue of the pattern coating.

  In the coating of the ground coating, the ground coating is applied directly or via a coating film of an undercoat after the base treatment. It is preferable to use an appropriate coating apparatus such as a roll coater. However, not only coating but also electrostatic coating or electrodeposition coating using a spray coater may be used. In the case where the ground paint is applied through the undercoat paint film, the ground paint is preferably applied after the undercoat paint is dried and cured.

  The thickness of the ground coating film is preferably 10 to 30 μm as a dry film thickness. When the coating thickness is 10 μm or more, the concealing property is good. If the thickness of the coating film exceeds 30 μm, coating film defects such as cracks may occur or the processability may be deteriorated, and the concealability is saturated, so that the cost only increases. On the contrary, if the coating film thickness is too thin, the base treatment layer and the undercoat coating film cannot be concealed. The coating thickness is more preferably 12 to 18 μm.

  In a normal coated metal plate, it is sufficient to form only one layer of the ground coating film. However, depending on the purpose, the ground coating film can be formed into two or more layers.

  The coating of the ground coating can be baked in the same way as described for the undercoat. The viscosity of the paint is adjusted to 30 to 150 seconds with Ford Cup # 4, and after painting, it is heated and baked. Baking of the ground coating film can be performed by baking for about 40 to 80 seconds so that the maximum reached temperature of the metal plate is 180 to 250 ° C.

  In addition, it is necessary to perform baking of the ground coating before applying the paint of the top coating film.

(5) About top coat film:
The top coating film is a coating film formed so as to cover a part of the ground coating film, and is partially formed on the ground coating film. The paint for the top coat film can be appropriately selected according to the part of the product where the coated metal plate is used, but a paint having excellent adhesion between the ground paint film and the pattern paint film can be used. It is preferable to use it. A paint having the same hue as that of the top coat film may be used, but a different hue is preferable.

  The resin type used for the top coating is the same as the resin type used for the above-mentioned (4) ground coating. For example, an epoxy resin, a polyester resin, a urethane resin, or a fluorine resin can be used. When weather resistance and workability are required, polyester-based, urethane-based and fluorine-based resins are preferable. About the specific aspect of these resin, it is the same as that of what was demonstrated in the ground coating film.

  The solvent of the paint used may be either an aqueous or organic solvent, or may be a powder paint that does not use a solvent.

  The paint for the top coat film may contain two or more kinds of resin. The top coat film may be a single layer, but may be two or more layers depending on the application. Since the top coating film is a coating film that serves as a base for randomly coating the island-shaped pattern coating film, it is necessary to use a top coating paint having a hue different from that of the pattern coating. Therefore, a color pigment can be appropriately contained so that the top coat film has a desired hue.

  The thickness of the top coat film is 3 to 20 μm, preferably 5 to 13 μm, as a dry film thickness. When the coating thickness is thick, the concealability is good. If it is too thick, coating film defects such as cracks may occur or processability may be deteriorated, and concealment will be saturated, which only increases the cost. Conversely, if the coating film thickness is too thin, the ground coating film cannot be concealed.

  As described above, the coating of the top coat film is partly painted so as to cover a part of the ground coating film. It is preferable to use a partial coating method such as a gravure offset printing method.

  Here, when the top coat film is applied so as to cover a part of the ground coating film, when it is applied by a roll coater, one or several strip-like top coating films having a certain width are ground coating films. It will be partially formed on top.

  The impression of the pattern varies depending on the shape and number of the top coating film formed on the ground coating film and the area ratio of the top coating film to the ground coating film. In consideration of the difference, it is preferable to appropriately examine various area ratios.

  Baking of the top coat film can be performed in the same manner as described for the ground paint. The viscosity of the paint is adjusted to 30 to 150 seconds with Ford Cup # 4, and after painting, it is heated and baked. Baking of the ground coating film can be performed by baking for about 40 to 80 seconds so that the maximum reached temperature of the metal plate is 170 to 250 ° C.

  The top coating must be applied after the ground coating is baked. As will be described later, by changing the wettability of the ground coating film and the top coating film as the foundation when spraying pattern paint, the size of the pattern of the island pattern coating film to be formed is changed to that on the ground coating film. This is because it can be changed depending on the top coat film, and as a result, a pattern-coated metal plate in which large patterns and small patterns are appropriately distributed.

(6) About island pattern coating film:
The pattern coating film is a coating film applied on the ground coating film or the top coating film, and an island-like pattern is randomly formed on the ground coating film or the top coating film. The paint for the pattern coating is preferably a paint having excellent adhesion between the ground coating and the top coating.

  It is necessary to use a pattern paint having a different hue from the ground coating film and the top coating film. The impression of the pattern on the patterned metal plate affects not only the hue of the island-shaped pattern coating film but also the hue of the base ground coating film and the top coating film, so that various hue combinations are possible.

  As the paint for the pattern coating film, for example, epoxy, polyester, urethane, and fluorine resins can be used. When weather resistance and workability are required, polyester-based, urethane-based and fluorine-based resins are preferable. About the specific aspect of these resin, it is the same as that of what was demonstrated in the ground coating film. Specific embodiments of the individual resin types are the same as those described above in (3) Undercoat film, (4) Ground film, and (5) Topcoat film. The paint for the pattern coating film may contain only one kind of resin, but may contain two or more kinds of resin. Although a resin type different from the paint used for the ground paint may be used, it is preferable to use a paint of the same resin type.

  The island-shaped pattern coating film is formed by spraying a paint having a different hue from the ground coating film and the top coating film in order to reveal the island-shaped pattern on the ground coating film and the top coating film. . At this time, spray coating may be performed using a coating made of a resin type different from the resin type used for the coating of the ground coating film and the top coating film, but it is preferable to apply using a coating made of the same resin type. . Spray coating may be performed only once, but two or more coatings may be performed simultaneously or sequentially. When spray coating is performed a plurality of times, spray coating may be performed using a pattern paint made of different resin types, but it is preferable to apply using a pattern paint made of the same resin type. In the case of performing spray coating a plurality of times, the paint of the pattern coating film may be the same hue paint, or a different hue paint.

  The solvent of the paint used may be either an aqueous or organic solvent, or may be a powder paint that does not use a solvent. When using a solvent, it is preferable to adjust the paint viscosity to about 10 to 60 seconds with Ford Cup # 4 by thinner dilution or the like according to JIS 5400. When the paint viscosity exceeds 60 seconds, it becomes difficult to control the size of the sprayed paint particles. And if the viscosity is less than 10 seconds, the amount of thinner will increase too much, which not only increases the cost, but also reduces the thickness of the pattern coating, so it is not possible to obtain a hue that hides the ground coating There is.

  The coating of the pattern coating film needs to be applied after the ground coating film is dried or baked, and the top coating film is undried.

  FIG. 1 is a schematic view of an example of a cross section of a pattern-coated metal plate according to the present invention. After the base coating 2 is applied to one side of the metal plate 1, an undercoat film 3 and a ground coating film 4 are formed and dried or baked, and then a part of the ground coating film 4 is covered so as to cover a part of the ground coating film 4. The state when the coating film 5 is formed and the pattern-forming paint is spray-coated in an island shape from the exposed portion of the ground coating film 4 and the top coating film 5 is shown. The island-shaped pattern coating film includes a pattern coating film 6-1 having a small pattern size formed on the ground coating film and a pattern coating film 6-2 having a large pattern size formed on the top coating film. In this way, they are formed simultaneously.

  When spray coating of the pattern coating is performed on the ground coating after drying or baking, the paint of the pattern coating does not spread on the ground coating, so an island pattern 6-1 with a small pattern size is formed. In addition, the patterned coating film tends to have a convex shape.

  On the other hand, when the paint of the pattern coating is spray-coated on the undried top coat, the fluidity of the pattern paint on the top coat is large and spreads over the top coat to increase the pattern size. The island-shaped pattern 6-2 is formed and is in close contact with the top coat film. In addition, since the surface of the pattern coating film is substantially flat, for example, even if severe processing is applied, the paint on the pattern part is peeled off and is difficult to fall off.

  In this way, when the pattern paint is spray-coated simultaneously on the ground paint film and the top coat film, the small island pattern paint and the top coat paint on the ground paint A large pattern-sized island-shaped paint having a flat surface to be coated forms a small-pattern coating film and a large-pattern coating film, respectively. Therefore, it is possible to provide a pattern-coated metal plate in which patterns of large and small sizes are appropriately distributed, and the island-like pattern can also have three-dimensionally different shapes. Therefore, it is not monotonous and the design is improved.

  Furthermore, it is necessary to use a pattern paint having a different hue from the ground paint and the top coat film as the pattern paint for forming the island-like pattern paint film. Therefore, a coloring pigment can be appropriately contained as necessary so that the pattern coating film has a target hue.

  The spread of the pattern paint, and the pattern size of the pattern paint, depends on the time it takes for the paint film to harden after the sprayed island-shaped pattern paint adheres to the ground or top coat and the viscosity of the pattern paint. Also depends.

  The paint viscosity is adjusted to 10 to 60 seconds with Ford Cup # 4. The spray coating conditions are: spray air amount is 100 to 200 NL / min, pattern air amount is 100 to 200 NL / min, and metal plate moving speed is 40. Perform at ~ 130 m / min.

  Then, baking is performed for about 40 to 80 seconds so that the maximum temperature of the metal plate is 170 to 250 ° C. The pattern coating film is baked simultaneously with the baking of the top coat film.

  The thickness of the pattern coating film is preferably about 2 to 8 μm in terms of dry film thickness in the pattern coating film formed on the top coating film. When the thickness of the pattern coating film is 2 μm or more, the ground coating film can be concealed with a different hue, but when the thickness exceeds 8 μm, there is a possibility that a crack will occur. Further, when the thickness of the pattern coating film is 2 μm or more, the ground coating film can be concealed with a different hue.

(7) About pattern size of island pattern coating film:
The island pattern coating film is formed in a circular shape or an elliptical shape. As for the pattern size, the maximum pattern diameter is preferably 1.5 to 3 mm on the ground coating film, and the maximum pattern diameter is preferably 3.5 to 6 mm on the top coating film.

  The maximum pattern diameter was determined by selecting five island-shaped patterns in an arbitrary area of 3 cm × 3 cm in descending order of area and averaging the maximum diameters of the patterns.

(8) About area ratio of island pattern coating film to ground coating film:
The area ratio of the pattern coating film existing in an island shape on the ground coating film to the ground coating film is preferably 20 to 80%.

(9) About the area ratio of the island pattern coating film to the top coating film:
As for the area ratio with respect to the top coat film of the pattern paint film which exists in an island form on the top coat film, 20 to 80% is preferable.

(10) Other:
In addition, although the coating film according to this invention may be formed only in the single side | surface used as the outer plate | plate of a raw material, you may form in both surfaces of a raw material if desired. In the case of forming only on one side, the unpainted surface may be bare, or may be subjected only to a ground treatment, or may be coated differently from the present invention. When forming on both surfaces, the structure of the ground coating film and the pattern coating film may be the same on both surfaces, or may be different.

Preparation method of test materials:
A molten 55% Al—Zn alloy plated metal plate (metal plate thickness 0.5 mm) having a plating composition of Al: 55% by mass, Zn: 44% by mass, and Si: 1% by mass is used as a base material. As the treatment, the following coating type chromate treatment was performed.

  Coating type chromate treatment solution (“NRC 300” manufactured by Nippon Paint Co., Ltd.) is applied with a bar coater so that the amount of chromium deposited is 30 mg / m2, and heated for 5 seconds so that the maximum temperature reaches 100 ° C. , Dried.

  An epoxy paint (“KP Color 8699” manufactured by Kansai Paint Co., Ltd.) is applied as an undercoat on the surface of the molten 55% Al—Zn alloy-plated metal plate thus subjected to the base treatment, and the viscosity of the paint is 40 seconds with Ford Cup # 4. The coating was applied with a bar coater, and baked so that the maximum temperature reached 210 ° C. with a baking time of 30 seconds, and an undercoat film having a thickness of 5 μm at the time of drying was obtained.

  Separately, a polyester paint (“KP1510” manufactured by Kansai Paint Co., Ltd.) is prepared as a paint to be used for the ground paint film, the top coat film and the pattern paint film, and various additives such as pigments are added thereto. A paint having a hue was prepared.

  The paint used for the ground coating is a brown color whose paint viscosity is adjusted to 100 seconds with a Ford Cup # 4. It is applied to the entire surface of the undercoat with a bar coater and reaches the maximum in a baking time of 50 seconds. Baking was performed so that the temperature was 230 ° C., and a ground coating film having a thickness of 15 μm at the time of drying was obtained.

  The paint used for the top coat is a beige color whose viscosity is adjusted to 100 seconds with a Ford Cup # 4. A film is partially pasted on the ground coat, and the entire surface is covered with a bar coater. After the application, the attached film was peeled off to form a partially overcoated film on the ground coating film. The top coat film had a thickness of 10 μm when dried after baking.

  The paint used for the pattern coating is a gray color whose paint viscosity is adjusted to 20 seconds with a Ford Cup # 4, and the paint is sprayed onto the ground coating partially covered with the top coat with a spray gun. Spray painting.

  The spray coating was carried out at a spray air amount of 150 NL / min, a pattern air amount of 120 NL / min, and a moving speed of the metal plate of 60 m / min.

  Then, it performed simultaneously with baking of a top coat film and a pattern coating film. The baking condition was 50 seconds so that the maximum temperature reached by the metal plate was 230 ° C. As a result, the thickness after baking of the pattern coating film formed on the top coating film was 6 μm when dried.

  FIG. 2 is a schematic view (top view) of the painted surface of the pattern-coated metal plate obtained in this manner. The arrows in the drawing indicate the moving direction of the coated metal plate when spraying the pattern paint. Here, two strip-like top coat films 5 are formed so as to cover a part of the ground coat film 4, and the pattern forming paint is formed in an island shape from the exposed portion of the ground coat film 4 and the top coat film 5. For spray coating, an island-shaped pattern coating film is formed on the ground coating film 4 with a pattern pattern 6-1 having a small pattern size, and a pattern having a large pattern size on the top coating film 5. A coating film 6-2 is formed. In this way, a pattern-coated metal plate having excellent design properties in which large and small pattern sizes are appropriately distributed can be obtained.

  Here, the pattern size of the island-shaped pattern coating film is as shown in Table 1.

  As a result, a clear difference was observed between the pattern size of the island pattern coating film on the ground coating film and the pattern size of the island pattern coating film on the top coating film. The improvement of design property has been confirmed.

  According to the present invention, it is possible to provide a pattern-coated metal plate excellent in design and capable of giving an impression of a clear pattern without being too regular, and a method for producing the same.

It is a schematic diagram of an example of the cross section of the pattern coating metal plate which concerns on this invention. It is a schematic diagram (top view) of the coating surface of the pattern coating metal plate which concerns on the Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Metal plate 2 Ground treatment 3 Undercoat coating 4 Ground coating 5 Top coating 6-1 Pattern coating on ground coating 6-2 Pattern coating on top coating

Claims (8)

  A coated metal plate having a ground coating film, a top coating film, and a ground coating film and a pattern coating film having a hue different from that of the ground coating film on at least one side of the ground metal plate, A design characterized in that it covers the entire surface of the ground treatment layer, the top coating film covers a part of the ground coating film, and the pattern coating film exists in an island shape on the ground coating film and / or the top coating film. Pattern coated metal plate with excellent properties.   On at least one side of the metal plate that has been subjected to the base treatment, it is a coated metal plate having an undercoat coating film, a ground coating film, a top coating film, and a ground coating film and a top coating film in order of a pattern coating film having a different hue, The undercoat coats the entire surface of the undercoat layer, the ground coat coats the entire undercoat coat, the top coat coats part of the ground coat, and the pattern coat coats the ground coat and / or topcoat. A pattern-coated metal plate excellent in design, characterized in that it exists in the form of islands on a coating film.   The pattern-coated metal sheet having excellent design properties according to claim 1 or 2, wherein the hues of the ground coating film and the top coating film are different.   The maximum pattern diameter in the pattern coating film existing in an island shape on the ground coating film is 1.5 to 3 mm, and the maximum pattern diameter in the pattern coating film existing in an island shape on the top coating film is 3. The pattern-coated metal plate having excellent design properties according to any one of claims 1 to 3, wherein the pattern-coated metal plate is 5 to 6 mm.   The design property according to any one of claims 1 to 4, wherein the area ratio of the pattern coating film existing in an island shape on the ground coating film to the ground coating film is 20 to 80%. Excellent pattern painted metal plate.   The design property according to any one of claims 1 to 5, wherein an area ratio of the pattern coating film existing in an island shape on the top coating film to the top coating film is 20 to 80%. Painted metal plate.   After applying the ground treatment to at least one surface of the metal plate, the ground coating is applied to the entire surface of the ground treatment layer and baked, and then the top coating film is applied so as to cover a part of the ground coating film. A pattern-coated metal sheet with excellent design characteristics, characterized in that one or more types of pattern-forming paints with different hues from top-coating paints are spray-coated in islands and then the top-coating paints and pattern-forming paints are baked and cured. Production method. At least one side of the metal plate is ground-treated, and the ground coating is applied to the entire surface of the ground-treatment layer via an undercoat paint and baked, and then the top coat film is applied so as to cover a part of the ground paint film. It is characterized by excellent design, characterized by spraying and curing one or more types of pattern-forming paints with different hues from the ground paint and the top-coat paint in an island shape and then baking and curing the top-coat paint and the pattern-form paint. A method of manufacturing a patterned metal sheet.

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