JP5057841B2 - Multilayer pattern coating film forming method - Google Patents

Description

  The present invention relates to a method for forming a multilayer pattern coating film.

  Industrial products such as automobile bodies, interior parts, home appliances, and furniture are usually coated with paints for product protection and aesthetics.

  In recent years, in the appearance of the industrial products, it has been required to improve the aesthetics by applying a novel design. In particular, it is required to enhance the consumer's impression of the product by applying a design having a high quality texture by painting.

  Tsugaru coating, one of traditional crafts, can be mentioned as a painting that gives a design with a high quality texture. Tsugaru coating is a kind of lacquering technique, and it is a painting method that creates a lacquerware full of warmth and moisture through a huge man-hour that repeats the process of painting and sharpening. Among Tsugaru coatings, the Tang coating is a technique that repeats the process of applying colored lacquer, drying, and sharpening to form a complex spotted pattern. This is a time-consuming technique.

  As a coating method that can be used to apply such Tsugaru-painted Tang patterns at a low cost in a short period of time, instead of using lacquer, chemically synthesized paint is used, and primer coating, setting process, coating process, and coloring division are applied to the object. There is disclosed a method of applying a pattern through a process, a lacquering process, a wife coating process, a top coating process, a rough polishing process, a clear undercoating process, a middle polishing process, and a clear finishing process (see Patent Document 1). However, this method can shorten the drying time by using a chemically synthesized paint, but still requires a great number of steps and has a problem that it takes time and effort to complete.

In addition, as a manufacturing method that can industrially mass-produce painted decorative boards that mimic traditional craft lacquerware design, a process of attaching a chemical fiber cloth having a predetermined stitch on a substrate, a process of coloring the entire surface by painting A method of manufacturing a coated decorative board having a predetermined pattern by a step of partial coloring by partial coating, a step of polishing the surface, and a top coating step is disclosed (see Patent Document 2). However, this method requires a process of attaching a chemical fiber cloth to the substrate, and is not sufficient in terms of simplicity.
JP 7-51619 A JP-A-2005-47171

  An object of the present invention is to provide a method for forming a multilayer pattern coating film that can easily form a design similar to Tsugaru coating, which is a traditional craft.

  The inventor has intensively studied to achieve the above object. As a result, a colored paint for pattern formation is applied in a mountain-like and scattered pattern on the object to be coated, then the colored paint is applied to the entire surface, these paint films are ground to form a pattern, and then a clear paint is applied. It has been found that the object can be achieved. The present invention has been completed based on such knowledge.

  The present invention provides the following multilayer pattern coating film forming method.

1. (1) A pattern-forming coloring paint capable of forming a coating film having a color and / or texture different from that of the object to be coated is applied to the surface of the object so as to be applied in the form of peaks and dots. Forming a colored coating layer for forming;
(2) The entire surface of the colored coating film for pattern formation is coated with a colored coating material for whole surface coloring that can form a coating film having a color and / or texture different from that of the colored coating material for pattern formation to form an entire colored coating film layer. Process,
(3) Grinding the colored coating film for pattern formation and the colored coating film for overall coloring to form a pattern coating film, and
(4) a step of applying a clear paint on the formed pattern coating film to form a top clear coating layer;
A method for forming a multi-layer pattern coating film.

  2. Item 2. The method for forming a coating film according to Item 1, wherein a colored base paint is previously applied to the surface of the object to be coated.

  3. Item 2. The method for forming a coating film according to Item 1, wherein two or more types of coating materials capable of forming coating films having different colors and / or textures are used as the colored coating material for pattern formation.

  4). Item 4. The method for forming a coating film according to Item 3, wherein two or more kinds of paints used as a pattern-forming colored paint are applied using a spray gun having a plurality of paint discharge nozzles.

  5). Item 2. The method for forming a coating film according to Item 1, wherein in the step (2), the whole surface coloring paint is applied a plurality of times.

6). The color and / or texture between the colored coating film for pattern formation and the colored coating film for coating or the entire surface is (i) the lightness difference ΔL ^* by the L ^* C ^* h color system is 5 or more. (Ii) at least one selected from the group consisting of a hue difference Δh by the L ^* C ^* h color system being 45 or more, and (iii) a flip-flop value difference ΔFF being 0.2 or more. Item 2. The coating film forming method according to Item 1, which satisfies the requirements.

  7). Item 2. The method for forming a coating film according to Item 1, wherein the article to be coated is an automobile body or an interior part.

  8). A coated article in which a pattern coating film is formed on an article to be coated by the multilayer pattern coating film forming method according to Item 1.

The multilayer pattern coating film forming method of the present invention,
(1) A process of forming a colored coating film for pattern formation by coating the surface of the object to be coated with a colored coating for pattern formation so as to be applied in the form of peaks and dots.
(2) The entire surface of the colored coating film for pattern formation is coated with a colored coating material for whole surface coloring that can form a coating film having a color and / or texture different from that of the colored coating material for pattern formation to form an entire colored coating film layer. Process,
(3) a process of grinding a colored coating film for pattern formation and a colored coating film for full-color coloring to form a pattern coating film; and
(4) a step of applying a clear paint on the formed pattern coating film to form a top clear coating layer;
Is included.

  The multilayer pattern coating film forming method of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view schematically showing the steps (1) to (4) in one embodiment of the coating film forming method of the present invention.

  In FIG. 1, 1 is an object to be coated, 2 is a colored base coating layer, 3A and 3B are colored coating layers for pattern formation, 4 is an entire colored coating layer, and 5 is a pattern coating layer. , 6 respectively indicate a top clear coating layer.

  Referring to FIG. 1, step (1) includes two types of coatings having different colors and / or textures after forming a colored base coating layer 2 formed on the object 1 as necessary. The pattern-forming colored paint layer is applied by using a spray gun having two paint discharge nozzles so as to be applied in the form of peaks and dots on the colored base paint film surface. It is a process of forming 3A and the colored coating layer 3B for pattern formation. In step (2), the entire surface on which the colored paint for pattern formation is applied in step (1) and the entire surface on which the paint is not applied can form a coating film having a color and / or texture different from that of the paint. In this step, the coloring paint layer 4 is formed by applying a coloring paint using a spray gun. Step (3) is a step of forming the patterned coating film layer 5 by grinding the colored coating film for forming the patterned coating film and the entire colored coating film using sandpaper or the like. Step (4) is a step of forming the top clear coating layer 6 by applying a clear coating on the pattern coating using a spray gun.

  Hereinafter, each step will be described more specifically.

Process (1)
Step (1) is a step of forming a pattern-forming colored coating layer by coating the surface of the object to be coated with a pattern-forming colored paint so as to be applied in the form of peaks and dots.

Step (1) —Coating materials Examples of the coating materials include automobile bodies, automobile interior parts, home appliances, furniture, and the like. Examples of the objects to be coated include cold rolled steel sheets, galvanized steel sheets, zinc alloy plated steel sheets, stainless steel sheets, tin plated steel sheets, aluminum plates, aluminum alloy plates, magnesium plates, magnesium alloy plates, etc. Metal substrates; plastic substrates such as plastic molded bodies and plastic foams; glass substrates and the like.

  Moreover, as a to-be-coated object, the chemical conversion process, such as a degreasing process; a phosphate process and a chromate process, was given to the surface. Moreover, as a to-be-coated object, in order to provide concealment property, corrosion resistance, etc. on the surface, you may form undercoat films, such as a cationic electrodeposition coating material and a primer coating material. Furthermore, in order to improve chipping resistance, interlayer adhesion, etc., an intermediate coating film such as a thermosetting intermediate coating composition may be formed on the undercoat coating film. The undercoat and / or intermediate coat may be cured or uncured.

  If necessary, a colored base paint may be applied to the object to be coated before the pattern forming colored paint is applied. This is because by applying a colored base paint to the object to be coated, the brightness of the multilayer pattern coating film formed thereon can be adjusted, or a sense of depth can be imparted. In FIG. 1, 2 shows the coloring base coating film formed as needed.

  The colored base coating film can be formed by applying a liquid colored base paint comprising a resin component and a color pigment.

  As the colored pigment, known pigments for ink and paint can be used singly or in combination of two or more. Specific examples of the color pigment include metal oxide pigments such as titanium oxide and iron oxide; composite metal oxide pigments such as titanium yellow; carbon black, azo pigments, quinacridone pigments, diketopyrrolopyrrole pigments, and perylene pigments. Pigments, perinone pigments, benzimidazolone pigments, isoindoline pigments, isoindolinone pigments, metal chelate azo pigments, phthalocyanine pigments, indanthrone pigments, dioxane pigments, indigo pigments, etc. it can. Furthermore, those obtained by subjecting these color pigments to known surface treatments such as acid / base treatment, coupling agent treatment, plasma treatment, oxidation / reduction treatment and the like can also be used.

  The blending amount of the color pigment is preferably about 50 parts by mass or less with respect to 100 parts by mass of the resin solid content in the colored base paint from the viewpoint of the depth of the obtained multilayer coating film. More preferably, it is about part by mass.

  As the resin component contained in the colored base paint, it is preferable to use a thermosetting resin component. Specifically, for example, a base resin such as an acrylic resin, a polyester resin, an alkyd resin, or a urethane resin having a crosslinkable functional group such as a hydroxyl group, a melamine resin, a urea resin, a polyisocyanate compound, a block polyisocyanate compound, or the like. What used together with the crosslinking agent is mentioned. These base resin and crosslinking agent can be used by dissolving or dispersing in an organic solvent and / or a solvent such as water.

  If necessary, the coloring base paint may contain various additives such as rheology control agent, pigment dispersant, anti-settling agent, curing catalyst, antifoaming agent, antioxidant, ultraviolet absorber, extender pigment, etc. Can do.

  The colored base paint can be prepared by mixing and dispersing the aforementioned components.

  The colored base paint can be applied by a method such as electrostatic spray coating, air spray, or airless spray. The film thickness is preferably about 0.5 to 30 μm based on the cured coating film, from the viewpoint of the smoothness of the coating film, and more preferably about 5 to 25 μm. When spraying the colored base paint, the solid content is usually about 15 to 50% by mass, particularly about 20 to 40% by mass, and the viscosity at 20 ° C. is 10 to 30 seconds / It is preferable to adjust so that it becomes about Ford Cup # 4. The colored base coating film itself can be crosslinked and cured at a temperature of usually about 70 to about 150 ° C.

In the present invention, the colored base coating film preferably has a lightness L ^* in the L ^* a ^* b ^* color system defined by JIS 8729 of about 30 or less from the viewpoint of the depth of the multilayer coating film, More preferably, it is about 20 or less.

  In the present invention, when a colored base coating film is formed on an object to be coated, the colored base coating film may be cured or may remain uncured. Further, it may be in a semi-cured state.

Step (1) -In the formation step (1) of the colored coating film for pattern formation , if necessary, the colored coating material for pattern formation is formed in a mountain shape and a dotted pattern on the surface of the object on which the colored base coating film has been formed. Paint like a paint. In FIG. 1, 3A and 3B show the colored coating layer for pattern formation, respectively.

  The colored paint for pattern formation used in the method of the present invention is a liquid paint capable of forming a coating film having a different color and / or texture from the colored paint for coating or the entire surface. Here, in the case where a colored base coating film is formed on the object to be coated, the colored paint for pattern formation is a liquid paint capable of forming a coating film different from the color and / or texture of the colored base coating film. . Further, when a plurality of colored paints for pattern formation are used, these paints are also liquid paints that can form a coating film having a different color and / or texture.

In this specification, a color is specified by lightness, saturation, and hue. The texture means gloss, light transmittance, IV value, SV value, FF value, and the like. The color can be represented by chromaticity and lightness in a color system such as Munsell color system, L ^* a ^* b ^* color system, L ^* C ^* h color system, and XYZ color system. Further, the texture can be expressed by gloss and light transmittance of the coating film; IV value and SV value representing the metallic feeling in the glittering coating film; flip-flop value (FF value) representing the lightness ratio depending on the direction of vision. . Each of these characteristics can be measured using a commercially available color meter, spectrophotometer, gloss meter or the like, and can be calculated based on the measured value.

  The colored paint for pattern formation can contain a resin component, a color pigment, and / or a bright pigment.

  As the color pigment, one or a combination of two or more conventionally known pigments for ink and paint can be used. Specifically, those listed as the color pigments contained in the aforementioned colored base paint can be used in the same manner. The blending amount of the color pigment is preferably about 0.1 to 50 parts by mass with respect to 100 parts by mass of the resin component solid content in the colored paint for pattern formation from the viewpoint of the finished appearance of the obtained coating film. About 30 mass parts is more preferable.

  As the glitter pigment, one or a combination of two or more conventionally known pigments for ink and paint can be used. Specific examples of the bright pigment include a scale-like metal pigment such as aluminum, copper, nickel alloy, and stainless steel; a scale-like metal pigment whose surface is coated with a metal oxide; a scale-like metal pigment whose surface is chemically adsorbed with a colored pigment A scaly aluminum pigment in which an aluminum oxide layer is formed by causing a redox reaction on the surface; a colored aluminum pigment coated with a colored pigment or an inorganic metal oxide; a glass flake pigment; a surface coated with a metal or metal oxide Glass flake pigments; glass flake pigments with colored pigments chemically adsorbed on surfaces; interference mica pigments with surfaces coated with titanium dioxide; reduced mica pigments with interference colored mica pigments reduced; colored mica with colored pigments chemically adsorbed on surfaces Pigment; Colored mica pigment whose surface is coated with iron oxide; Graphite pigment whose surface is coated with titanium dioxide Plate-like iron oxide pigments; holographic pigments; synthetic mica pigment; alumina flake pigment coated surface with titanium dioxide; silica surface flakes coated with titanium dioxide and the like cholesteric liquid crystal polymer pigments having a helical structure.

  The blending amount of the glitter pigment is preferably about 0.5 to 100 parts by mass with respect to 100 parts by mass of the resin component solid content in the colored paint for pattern formation from the viewpoint of glitter and finish appearance of the obtained coating film. 1 to 50 parts by mass is more preferable.

  Specifically, as the resin component contained in the pattern-forming colored paint, those listed as the resin component contained in the above-described colored base paint can be used in the same manner.

  Furthermore, for paints for pattern formation, if necessary, solvents such as water and organic solvents, rheology control agents, pigment dispersants, anti-settling agents, curing catalysts, antifoaming agents, antioxidants, UV absorbers, etc. Various additives, extender pigments, gloss adjusting agents and the like can be appropriately blended.

  The colored paint for pattern formation can be prepared by mixing and dispersing the aforementioned components. The coating usually has a solid content of about 10 to 50% by weight, particularly about 15 to 40% by weight, and a viscosity at 20 ° C. of about 10 to 40 seconds / forward cup # 4. It is preferable to adjust.

  The colored paint for pattern formation can be applied by a method such as electrostatic coating, air spray, or airless spray. The coating film itself of the colored paint for pattern formation can be dried at room temperature or cured at a temperature of about 60 to about 150 ° C.

  The colored coating layer for pattern formation means a colored coating layer formed by coating the above-described colored coating composition for pattern formation on the surface of the object to be coated and forming a mountain shape and a dotted pattern on the object to be coated. The height of the mountain is preferably in the range of about 10 μm to 50 μm, more preferably in the range of about 15 μm to 40 μm, as a dry coating film, from the viewpoint of the design of the obtained multilayer pattern coating film. . The height of the mountain said here means the height of the coating layer of 3A and 3B of (1) of FIG. When the height of the mountain is lower than the above range, the surface exposed after grinding is mainly the colored base coating film or the entire colored coating film layer formed on the coating object or the coating object, and the pattern is monotonous. Tend to be. On the other hand, when the height of the mountain exceeds the above range, grinding may take too much time to obtain a desired pattern, or the smoothness of the coating film may be insufficient. On the other hand, the size of the mountain is less affected by the pattern formation than the height, but it is usually appropriate that the diameter after grinding is about 0.5 to 7 mm.

  In the method of the present invention, as a colored paint for pattern formation, one kind of paint may be used alone or two or more kinds of paints capable of forming different colors and / or textures may be used. . Of these, in particular, when using paints that can form two or more different colors and / or textures, two or more types of colored coating layers for pattern formation having different colors and / or textures are used. In combination with the color and texture of the object to be coated or the colored base coating film or the entire color coating film formed on the object to be coated, the pattern coating is excellent in depth and the design. This is preferable because it is easy to form a film.

  Here, when only one type of colored paint for pattern formation is used, the colored paint is applied to a part of the surface of the object so as to be applied in a mountain shape. It is preferable to form a colored coating film in the form of dots from the viewpoint of the design of the pattern coating film formed by grinding. In addition, when two or more kinds of colored paints for pattern formation are used, these colored paints are applied to the whole surface or part of the surface of the object to be coated in a mountain shape. It is preferable from the viewpoint of the design of the pattern coating film formed by grinding to form two or more kinds of colored coating films in the form of dots. In any of these cases, it is preferable that about 0% to 20% of the surface of the object to be coated is exposed after forming the colored coating layer for pattern formation, and about 5% to 15% is exposed. More preferably.

  The height of the crest of the colored coating layer for pattern formation can be adjusted by changing the paint conditions and the coating conditions when applying the colored paint for pattern formation. Here, the paint conditions mean the content of the coating film forming component of the paint, the viscosity, the specific gravity, the amount and composition of the diluent solvent, and the like. The painting conditions are the amount of paint applied per unit time, the amount of atomized air, gun distance, conveyor speed, spray gun nozzle diameter, spray when painting using a regipro coater equipped with an air spray gun. Means the moving speed of the gun.

  When using two or more types of colored paints for pattern formation, the paint can be applied using a spray gun having a plurality of paint discharge nozzles. This spray gun is a coating machine having one coating gun head in the coating machine, and the coating gun head has two or more, preferably 2 to 4 paint discharge nozzles. A pattern in which various coating colors are mixed can be formed by ejecting. Examples of such a spray gun include a spray gun described in JP-A-9-299833.

  As for the coating conditions in the case of applying a colored paint for pattern formation using a spray gun having a plurality of paint discharge nozzles, the pattern air amount is about 80 to 300 NL / min for each discharge nozzle, and the atomized air amount In the range of about 80 to 300 NL / min, it can be appropriately adjusted and coated. The atomizing air amount and the pattern air amount of each nozzle may be the same or different. The amount of atomizing air and the amount of pattern air can be appropriately adjusted according to the distance between the spray gun and the object to be coated. Moreover, the moving speed of the spray gun can be appropriately adjusted according to the height of the crest of the colored coating layer for pattern formation.

  In the method of the present invention, the colored paint for pattern formation to be used is different in color and / or texture from the object to be coated (the colored base paint film when a colored base paint film is formed) or the colored paint for overall coloration. In the case where a plurality of colored paints for pattern formation are used, these paints are also liquid paints capable of forming paint films having different colors and / or textures.

In the method of the present invention, the difference in color and / or texture may be any one of an object to be coated, a single coating of a colored base coating, a single coating of a colored coating for pattern formation, and a single coating of a full-color coating. As for the color and / or texture between the two, (i) the lightness difference ΔL ^* by the L ^* C ^* h color system is 5 or more, (ii) the hue difference Δh by the L ^* C ^* h color system is Satisfying at least one requirement selected from the group consisting of 45 or more and (iii) the difference ΔFF of the flip-flop value is 0.2 or more in the design diversity of the pattern coating film to be obtained It is preferable from the point of being excellent, and it is more preferable to satisfy two or more requirements.

The L ^* C ^* h color system is a color system defined by the International Lighting Commission and is described in Section 4.2 of CIE Publication 15.2 (1986). In the L ^* C ^* h color system, L ^* represents lightness, h represents a hue angle, and this hue angle is an angle moved counterclockwise with the red axis as 0 ° in the chromaticity diagram. . The lightness L ^* and the hue angle h can be measured using a color difference meter, a multi-angle spectrophotometer, or the like. A commercially available product can be used as the color difference meter. Examples of commercially available products include “CR Series” (trade name) manufactured by Konica Minolta, “SM Color Computer” (trade name) manufactured by Suga Test Instruments Co., Ltd., and the like. Moreover, a commercial item can be used as a multi-angle spectrophotometer. As a commercial item, "MA-68" (brand name) by X-Rite, etc. are mentioned, for example.

  The flip-flop value represents a lightness ratio that varies depending on the visual direction, and particularly shows a remarkable value in a glittering coating film. The flip-flop value can be measured using, for example, a multi-angle spectrophotometer. A commercially available product can be used as the multi-angle spectrophotometer. As a commercial item, "MA-68" can be used, for example. According to the multi-angle spectrophotometer, the spectral reflectance obtained by receiving incident light irradiated at an angle of 45 degrees with respect to the coating film surface at angles of 15, 25, 45, 75, and 110 degrees with respect to the regular reflection light. Can be measured.

In the present invention, the flip-flop value (FF value) is calculated based on the L ^* value (referred to as “L15”) calculated based on the spectral reflectance at a light receiving angle of 15 degrees and the spectral reflectance at a light receiving angle of 45 degrees. It is a value calculated from the calculated L ^* value (referred to as “L45”) by the following calculation formula (1). Here, ^{L *} value is a ^{L *} value in ^{the L} * ^a * ^{b *} color system defined in JIS Z 8729.

FF value = [2 × (L15−L45)] / (L15 + L45) (1)
In the method of the present invention, the color and / or texture of the coating film obtained by independently applying the colored paint for pattern formation is obtained by applying the coating material to be measured on the coating plate on which the gray coating film is formed. The coating film obtained by coating to a film thickness of 30 μm based on the above and leaving it to stand at room temperature for 10 minutes, followed by heating and curing at 60 to 150 ° C. for 30 minutes in a hot-air circulating drying oven Means the color and / or texture measured by the measurement method described above. Here, the gray color indicates the spectral reflectance obtained by using a multi-angle spectrophotometer to receive incident light irradiated at an angle of 45 degrees with respect to the coating film surface at an angle of 45 degrees with respect to the regular reflection light. Measure and use 55 L ^* values calculated from the measured values.

Process (2)
In step (2), the entire surface of the colored coating film for pattern formation formed in step (1) is coated with a colored coating material for whole surface coloring that can form a coating film having a color and / or texture different from that of the colored coating material for pattern formation. Then, it is a step of forming the entire colored coating layer. Here, when the pattern coloring paint is not applied to a part of the object to be coated, the surface of the exposed object to be coated (or the colored base film when the colored base film is formed) is exposed. At the same time, a colored paint for whole-surface coloring is applied to form a continuous whole-colored coating film layer.

  In FIG. 1, 4 means an entire colored coating layer. In the method of the present invention, after the colored coating layer for pattern formation is formed, a colored coating for overall coloring is further applied to form one or more entire colored coating layers. When forming two or more full-color colored coating layers, first paint the first full-color coloring paint, dry or cure, and then apply the second full-color coloring paint to the resulting coating surface Then, it can be dried or cured to form the second entire colored coating layer. The entire colored coating layer is preferably from 1 to 4 layers from the viewpoint of the design properties of the multilayer coating, and particularly preferably 1 layer or 2 layers. When there are three or more full-color coating layers, it is possible to form a plurality of overall colored layers by repeating the step of applying and drying or curing the full-color coloring paint three or more times as described above. it can. FIG. 1 shows a case where the entire colored layer is one layer.

  The colored paint for coloring the entire surface is a liquid paint containing a resin component, a colored pigment and / or a bright pigment. The coloring pigment may contain one or a combination of two or more conventionally known pigments for inks and paints. Specifically, those mentioned as the color pigments to be contained in the aforementioned colored base paint can be used in the same manner.

  The blending amount of the color pigment is preferably about 0.1 to 50 parts by mass with respect to 100 parts by mass of the solid content of the resin component in the colored paint for overall coloration in terms of the finished appearance of the coating film to be obtained. About 30 mass parts is more preferable.

  As the luster pigment contained in the colored paint for coloring the entire surface, conventionally known pigments for ink and paint can be used alone or in combination of two or more. Specifically, those mentioned as the luster pigment to be contained in the above-mentioned pattern forming coloring paint can be used in the same manner. The blending amount of the glitter pigment is preferably about 0.5 to 100 parts by mass with respect to 100 parts by mass of the solid content of the resin component in the colored paint for overall coloration from the viewpoint of the glitter feeling and finished appearance of the resulting coating film. 1 to 50 parts by mass is more preferable.

  As the resin component of the colored paint for coloring the entire surface, those listed as the resin component contained in the aforementioned colored base paint can be used in the same manner.

  Furthermore, for colored paints for full-color coloring, if necessary, solvents such as water and organic solvents, rheology control agents, pigment dispersants, anti-settling agents, curing catalysts, antifoaming agents, antioxidants, UV absorbers, etc. Various additives, extender pigments, gloss adjusting agents and the like can be appropriately blended.

  The colored paint for coloring the entire surface can be prepared by mixing and dispersing the aforementioned components. Usually, at the time of coating, the solid content is about 10 to 50% by weight, particularly about 15 to 40% by weight, based on the coating composition, and the viscosity at 20 ° C. is 10 to 40 seconds / ford cup #. It is preferable to adjust to about 4.

  The coloring paint for coloring the entire surface can be applied by a method such as electrostatic coating, air spray, or airless spray. The entire colored paint film itself can be dried at room temperature or cured at a temperature of about 60 to about 150 ° C.

  In the method of the present invention, the thickness of the entire colored coating film layer is preferably in the range of about 5 μm to 40 μm, more preferably in the range of about 10 μm to 35 μm, as a dry or cured coating film. If this range is exceeded, the grinding process may take time, and it is difficult to form a continuous colored layer with a film thickness below the lower limit of this range.

In the method of the present invention, the color and / or texture of the entire colored coating layer and the pattern forming colored coating layer are different from each other, and 1) the lightness difference ΔL by the L ^* C ^* h color system is 5 or more. 2) The hue difference Δh according to the L ^* C ^* h color system is 45 or more, and 3) one or more requirements selected from the requirements that the difference in flip-flop values is 0.2 or more are satisfied. From the viewpoint of the diversity of design of the pattern coating film, it is particularly preferable to satisfy two or more requirements.

  In the case of forming two or more full-color layers, it is preferable that the color and / or texture of adjacent full-color layers be different from each other and satisfy the same requirements as described above.

Process (3)
Step (3) is a step of grinding the colored coating film for pattern formation and the entire colored coating film to form a pattern coating film. Here, the colored coating film for pattern formation and the entire colored coating film may be cured or uncured. Further, it may be in a semi-cured state.

  In FIG. 1, 5 means a pattern coating layer formed by grinding. Although it does not specifically limit as a grinding method, For example, it can grind using a sandpaper. Sandpaper is a paper base material such as kraft paper or Japanese paper or a cloth containing a mesh base material, which is treated with a grinding agent such as alumina and attached with an adhesive. The smaller the number, the coarser the abrasive, and the larger the number, the finer the abrasive.

  In the present invention, for example, a rough sandpaper of about # 600 is used, and part of the colored coating film for pattern formation and the entire colored coating film is removed by grinding until a desired pattern is developed. A fine sandpaper can be used to finish the surface smooth. In addition, in order to prevent clogging due to the coating residue left by grinding, grinding can be performed using water or oil. At this time, grinding can be performed more efficiently by using a sander belt having sandpaper. With respect to the degree of grinding, since the pattern is crushed if it is cut too much, and the pattern becomes small and deviates from the target design if there is not enough cut, it is preferable to perform grinding within a range where the object to be coated is not exposed.

  In the present invention, when a clear coating film is formed after grinding, if the paint residue remains, it may cause adhesion failure. Therefore, after grinding, washing and degreasing are performed to clean the ground surface. Is preferable.

The pattern coating film formed by grinding forms a variety of patterns when observed from the surface. In the formed pattern coating film, the colors of the pattern-forming colored coating film and the entire colored coating film are mixed. In this invention, it is preferable to form a coating film so that the color difference of the adjacent area | region in this pattern coating film may be 5 or more, and it is more preferable to form so that a color difference may be 10 or more. Here, the color difference means ΔE in the L ^* a ^* b ^* color system. The measurement conditions are that the illumination light of the D65 light source is applied to the coating film from an angle of 45 °, and the coating film receives light in the vertical direction (10 ° field of view).

In the present invention, the coating film is preferably formed such that the lightness L ^{* of the} portion occupying the largest area in the formed patterned coating film is 50 or less, particularly preferably 30 or less. Lightness ^{L * is} meant ^{L *} in the L ^* a * ^{b *} color system. The measurement conditions are that the illumination light of the D65 light source is applied to the coating film from an angle of 45 °, and the coating film receives light in the vertical direction (10 ° field of view). Many traditional crafts have low brightness based on black, and the above brightness range is preferable in order to reproduce these textures. In the formed pattern coating film, it is possible to form the coating film so that the average particle diameter of the same color and continuous region is within the range of about 0.5 mm to 7 mm. In view of the fact that a well-balanced design effect can be exhibited. The average particle diameter is more preferably in the range of about 1 mm to 5 mm.

  The average particle diameter of a continuous region of the same color can be obtained as follows. (1) Capture the pattern coating film with a scanner (100-200 dpi). (2) Cut out the image (256 x 256 pixels). (3) A continuous area having the same color is formed into a sphere by image processing, and the number is counted (using Image J). (4) Find the area of the spheroidized part (using Image J). (5) The average particle diameter is calculated from the spherical count obtained in (3) and the area obtained in (4). Compared to the shape and size of the component to be painted, a well-balanced design effect can be achieved, so the particle size in the above range is preferable. Image J is public domain image processing software developed by NIH (National Institutes of Health).

  Furthermore, it is preferable that the fractal dimension number of the same color and continuous region in the formed pattern coating film be in the range of about 1.55 to 1.98. Here, the fractal dimension is an index representing the complexity of a figure (pattern). If the number of dimensions of the fractal dimension is about 1.55 or less, the pattern is less complicated and only appears as an independent point (leopard pattern). On the other hand, if it is about 1.98 or more, the pattern is too complicated and assimilated, In either case, it is not preferable as a pattern appearance. The fractal dimension number is more preferably in the range of 1.75 to 1.98.

  The fractal dimension number can be obtained as follows. (1) Read the pattern coating film with a scanner (100-200 dpi). (2) Convert the size to a size of 256 to 512 pixels. (3) After conversion to grayscale, binarize so that the pattern part is white and the other part is black. (4) Fractal dimension number is calculated by Box-Count method of Image J analysis tool.

Process (4)
Step (4) is a step of forming a top clear coating layer by applying a clear coating onto the pattern coating formed in step (3). Here, the patterned coating film may be cured or uncured. Further, it may be in a semi-cured state.

  In FIG. 1, 6 means the top clear coating layer formed in the step (4).

  A clear paint is a colorless or colored transparent paint composed mainly of a resin component and a solvent such as water or an organic solvent, and further, if necessary, paint additives such as color pigments, dyes, and gloss adjusting agents. It is a liquid paint that forms a film. The clear paint covers the surface of the formed pattern coating film to make it smooth or to provide weather resistance, water resistance, and chemical resistance. In addition, when a clear paint containing a gloss adjusting agent is applied, a soft textured film can be obtained by suppressing gloss.

  As the clear paint, a conventionally known clear paint can be used without limitation. For example, a liquid coating composition containing a base resin and a crosslinking agent can be applied as the resin component.

  Examples of the base resin include acrylic resins, polyester resins, alkyd resins, fluororesins, urethane resins, and silicon-containing resins containing a crosslinkable functional group such as a hydroxyl group, a carboxyl group, a silanol group, and an epoxy group. Examples of the crosslinking agent include melamine resin having a reactive group capable of reacting with the functional group of the base resin, urea resin, polyisocyanate compound, block polyisocyanate compound, epoxy compound or resin, carboxyl group-containing compound or resin, acid An anhydride, an alkoxysilane group-containing compound, a resin, or the like can be given. Moreover, additives, such as solvents, such as water and an organic solvent, a curing catalyst, an antifoamer, and a ultraviolet absorber, can be suitably mix | blended as needed.

  In the clear paint in the method of the present invention, a color pigment, a dye, a gloss adjusting agent and the like can be blended in a timely manner within a range not impairing transparency.

  As the color pigment that can be contained in the clear paint, conventionally known pigments for ink and paint can be used singly or in combination. Specifically, those mentioned as the color pigments to be contained in the aforementioned colored base paint can be used in the same manner.

  When blending the above color pigment, the blending amount is usually 0.001 to 5 parts by mass with respect to 100 parts by mass of the resin component solid content in the clear paint from the viewpoint of the transparency and finished appearance of the resulting coating film. The degree is preferable, and about 0.01 to 3 parts by mass is more preferable.

  As the dye that can be contained in the clear paint, conventionally known dyes for ink, paint, and plastic can be used singly or in combination. Specific examples of the dye include azo dyes, anthraquinone dyes, copper phthalocyanine dyes, metal complex dyes, and the like.

  When the above dye is included, the blending amount is usually about 0.001 to 5 parts by mass with respect to 100 parts by mass of the resin component solid content in the clear paint from the viewpoint of the hue and finished appearance of the obtained coating film. Is preferable, and about 0.01-3 mass parts is more preferable.

  As the gloss adjusting agent that can be contained in the clear paint, conventionally known gloss adjusting agents for ink and paint can be used singly or in combination. Specifically, powdery or particulate silica, ceramics and other inorganic materials and resin fine particles such as acrylic resin and urethane resin can be used, but are not particularly limited.

  When the clear coating material contains a gloss adjusting agent, the blending amount thereof is usually 1 with respect to 100 parts by mass of the resin component solid content in the clear coating material, in terms of the gloss value range and finish of the coating film obtained. About 30 mass parts is preferable, and about 3-60 mass parts is more preferable.

  Further, the clear coating can be applied by a method such as electrostatic coating, air spray, airless spray, etc., and the film thickness is about 100 to 300 μm based on the cured coating film from the viewpoint of excellent smoothness of the coating film. It is preferable to be within the range.

  The clear paint can be crosslinked and cured at a temperature of about 60 to about 150 ° C. after application.

  According to the method for forming a multi-layer pattern coating film of the present invention, a colored paint for pattern formation is applied in a mountain shape and a dotted pattern on an object to be coated, and then the colored paint is applied to the entire surface, and these coating films are ground. After the pattern formation, a design similar to Tsugaru coating, which is a traditional craft, can be industrially formed by a simple method of further applying a clear paint. Therefore, the remarkable effect that the design similar to Tsugaru coating which is a traditional craft can be easily formed is produced.

  Hereinafter, the present invention will be described in more detail with reference to production examples, examples and comparative examples. However, the present invention is not limited by these. Parts and% are based on mass in principle.

Manufacture example 1 Manufacture of to-be-coated thing The thing made from ABS resin panel (Brand name "Psycholac Y-665C", shape 100x150x1.5mm, Tanazawa Yako company make) degreasing using isopropanol Was to be coated.

Production Examples 2 to 5 Production of 1-4 A hydroxyl group-containing acrylic resin (hydroxyl value 80 mg KOH / g, number average molecular weight 20,000 measured by GPC method based on standard polystyrene) 100 parts (solid content) and the types shown in Table 1 At least one pigment of a blending amount of color pigment and glitter pigment is mixed with stirring, and 20 parts (solid content) of a polyisocyanate crosslinking agent (trade name “SOFLEX 5000”, HDI isocyanurate, manufactured by Kansai Paint Co., Ltd.) Next, a mixed organic solvent (toluene / xylene / ethyl acetate / acetic acid-3-methoxybutyl / diethylene glycol monobutyl ether acetate = 3/16/28/13/2) (mass ratio) is added, and paint No. . 1 and 4 were diluted with Ford Cup # 4 (20 ° C.) for about 20 seconds (solid content: about 25%). In No. 2 and No. 3, diluted with Ford Cup # 4 (20 ° C.) for about 35 seconds (solid content: about 35%). 1-4 were prepared.

About the obtained said 4 types of coating materials, the lightness L ^* of the single coating film, the hue h, and the flip-flop (FF) value were measured with the following method.

Lightness L ^* , hue h and FF value of a single coating film: The coating is formed on a tin plate on which a gray coating film (L ^* = 55) has been previously formed, so that the film thickness becomes 30 μm based on the cured coating film. The coating was allowed to stand at room temperature for 10 minutes, and then cured by heating at 140 ° C. for 30 minutes in a hot-air circulating drying oven. About the obtained coating board, the lightness L ^* , the hue h, and FF value of the coating material single coating film were measured with the following method.

(A) Measurement of lightness L ^* : A multi-angle spectrophotometer (trade name “MA-68”, manufactured by X-Rite) was used to measure the L ^* value at a light receiving angle of 45 degrees.

  (B) Measurement of hue h: A multi-angle spectrophotometer (trade name “MA-68”, manufactured by X-Rite) was used to measure h at a light receiving angle of 45 degrees.

(C) measurement of the FF value: multi-angle spectrophotometer (trade name "MA-68", manufactured by X-Rite Co., Ltd.) was used to the light-receiving angle of 15 degrees of the ^{L *} value and the light-receiving angle of 45 degrees of the ^{L *} value Was measured, and the FF value was calculated by the calculation formula (1).

Table 1 shows the pigment composition of each paint, the lightness L ^* , the hue h, and the FF value of a single coating film.

  In Table 1, the types of pigments are as follows. Moreover, the compounding quantity of a pigment is a part per 100 parts (solid content) of the resin component in a coating material.

Color pigment A: Pigment Black 7, trade name “Monarch 1300”, manufactured by Cabot Corporation, carbon black pigment.

  B: Pigment Red 101, trade name “TRANSOXIDE RED”, manufactured by Dainichi Seika Co., Ltd., transparent iron oxide pigment.

  C: Pigment Red 177, trade name “CHROMOPHTAL RED A2B”, manufactured by Ciba Specialty, anthraquinone pigment.

  D: Pigment Red 202, trade name “Quindo Magenta 202 RV6853”, manufactured by Dainippon Ink Chemical Co., Ltd., dichloroquinacridone pigment.

Bright pigment a: Colored gold mica pigment, trade name “IRIODIN 303 W2”, manufactured by Merck & Co., Inc.

  b: Colored red mica pigment, trade name “IRIODIN 504 W2,” manufactured by Merck & Co., Inc.

Production Example 6 Production of Clear Coating Polyisocyanate-based cross-linking with respect to 100 parts (solid content) of a hydroxyl group-containing acrylic resin (hydroxyl value 80 mg KOH / g, number average molecular weight 10,000 measured by GPC method based on standard polystyrene) 30 parts (solid content) of an agent (trade name “SOFLEX 5000”, HDI isocyanurate, manufactured by Kansai Paint Co., Ltd.), then mixed organic solvent (toluene / xylene / ethyl acetate / acetic acid-3-methoxy) Butyl / diethylene glycol monobutyl ether acetate = 3/16/28/13/2) (mass ratio) and diluted with Ford Cup # 4 (20 ° C) to about 35 seconds (solid content about 45%) Thus, an organic solvent-type clear paint was prepared.

Example 1 Preparation of Multilayer Pattern Coating Film The colored paint No. obtained in Production Example 2 was applied to the article obtained in Production Example 1. 1 was applied as a colored base paint using an air spray gun under the conditions of a booth temperature of 20 ° C. and a humidity of 60% so that the cured coating film had a thickness of 20 μm.

  Colored paint no. 1 was applied and allowed to stand at room temperature for 4 minutes, and the colored paint No. 1 obtained in Production Examples 3 and 4 was used as a colored paint for pattern formation. 2 and no. 3 using a spray gun having four paint discharge nozzles (trade name “S-type coating machine”, manufactured by NP Corp.) so that about 7% of the coating surface of the colored base paint is exposed. It was simultaneously applied under the conditions of a booth temperature of 20 ° C. and a humidity of 60% so that the peak height of the pattern-forming colored coating layer was about 15 μm as a cured coating film.

  Colored paint no. 2 and no. 3 was applied and allowed to stand at room temperature for 10 minutes to obtain the colored paint No. 3 obtained in Production Example 5. 4 was coated uniformly on the entire surface using an air spray gun as a coloring paint for coloring the entire surface under a booth temperature of 20 ° C. and a humidity of 60% so as to be about 15 μm as a cured coating film.

  Colored paint no. After 4 coatings, the mixture was allowed to stand at room temperature for 5 minutes and then heat-cured at 80 ° C. for 30 minutes in a hot-air circulating drying furnace. The coated surface after curing was roughly ground with # 600 sandpaper, and then finish ground with # 1000 sandpaper.

  Thereafter, it is washed with water, dried at 80 ° C. for 20 minutes in a dryer, degreased with petroleum benzene, and the surface scratches and rounds are filled, so that the clear coating obtained in Production Example 6 is about 150 μm as a cured coating film. Using an air spray gun, the paint was applied at a booth temperature of 20 ° C. and a humidity of 60%, and cured at 80 ° C. for 30 minutes. Thus, a multilayer pattern coating film was formed on the object to be coated.

  In the formation of the multilayer coating film, the exposed area (%) of the colored base coating film not coated with the pattern-forming colored paint was measured by the following method. That is, the image of the painted surface of the test plate is captured as electronic data on a personal computer using an image scanner (trade name “CanoScan 4400F”, manufactured by Canon Inc.), and image analysis software (software name “NIH Image”, The exposed area (%) of the first colored base paint film on the painted surface was measured by an image analysis software developed by Mr. Wany Rasband of National Institutes of Health (NIH).

In addition, the paint No. used above. The lightness difference ΔL ^* , hue difference Δh, and FF value difference ΔFF of any one of 1 to 4 were calculated from the lightness L ^* , hue h, and FF value of each single coating film shown in Table 1.

Table 2 shows the paint Nos. ΔL ^* , Δh, and ΔFF between any two of 1-4 were shown.

(4) Evaluation The created pattern coating film was evaluated. The lightness (L ^* ) of the coating film portion of the pattern coating film by the pattern forming paint is 30 or less, and the color difference (ΔE) between the pattern forming paint film and the coating film for full coloration adjacent thereto is 10 or more. there were. In addition, the average particle diameter of the paint film formed by grinding and exposing the pattern forming paint was about 5 mm, and the fractal dimension was about 1.8. Moreover, the pattern similar to Tsugaru coating which is a traditional craft design was able to be formed from visual evaluation.

FIG. 1 is a cross-sectional view schematically showing steps (1) to (4) in one embodiment of the coating film forming method of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... To-be-coated object 2 ... Colored coating film layer 3A ... Colored coating film layer for pattern formation 3B ... Colored coating film layer for pattern formation 4 ... Whole colored coating film layer 5 ... Pattern coating film layer 6 ... Top clear coating film layer

Claims (9)

(1) A pattern-forming coloring paint capable of forming a coating film having a color and / or texture different from that of the object to be coated is applied to the surface of the object so as to be applied in the form of peaks and dots. Forming a colored coating layer for forming ,
After the formation of the colored coating layer for pattern formation, 5 to 15% of the surface of the object to be coated is exposed ,
(2) The entire surface of the colored coating film for pattern formation is coated with a colored coating material for whole surface coloring that can form a coating film having a color and / or texture different from that of the colored coating material for pattern formation to form an entire colored coating film layer. Process,
(3) Grinding the colored coating film for pattern formation and the colored coating film for overall coloring to form a pattern coating film, and
(4) a step of applying a clear paint on the formed pattern coating film to form a top clear coating layer;
A method for forming a multi-layer pattern coating film. (0) A step of applying a colored base paint in advance to the surface of the object to form a colored base coating film ,
(1) On the surface of the colored base coating film, apply a pattern-forming colored paint capable of forming a coating film having a color and / or texture different from that of the object to be applied in a mountain-like and dotted-like manner, Forming a colored coating layer for pattern formation,
After the formation of the colored coating layer for pattern formation, a step in which 5 to 15% of the colored base coating surface is exposed,
(2) The entire surface of the colored coating film for pattern formation is coated with a colored coating material for whole surface coloring that can form a coating film having a color and / or texture different from that of the colored coating material for pattern formation to form an entire colored coating film layer. Process,
(3) Grinding the colored coating film for pattern formation and the colored coating film for overall coloring to form a pattern coating film, and
(4) a step of applying a clear paint on the formed pattern coating film to form a top clear coating layer;
A method for forming a multi-layer pattern coating film. The coating film forming method according to claim 1 or 2 , wherein two or more kinds of coating materials capable of forming coating films having different colors and / or textures are used as the colored coating material for pattern formation. The coating film forming method according to claim 3, wherein two or more kinds of paints used as a pattern-forming colored paint are applied using a spray gun having a plurality of paint discharge nozzles. The coating film forming method according to any one of claims 1 to 4, wherein in the step (2), the entire surface coloring paint is applied a plurality of times. The color and / or texture between the colored coating film for pattern formation and the colored coating film for coating or the entire surface is (i) the lightness difference ΔL ^* by the L ^* C ^* h color system is 5 or more. (Ii) at least one selected from the group consisting of a hue difference Δh by the L ^* C ^* h color system being 45 or more, and (iii) a flip-flop value difference ΔFF being 0.2 or more. The coating-film formation method as described in any one of Claims 1-5 which satisfy | fills a requirement. The method for forming a coating film according to any one of claims 1 to 6 , wherein the article to be coated is a car body or an interior part of an automobile. The method as described in any one of Claims 1-7 for forming a Tsugaru coating-like coating film. The coated article by which the pattern coating film was formed on the to-be-coated article by the multilayer pattern coating-film formation method as described in any one of Claims 1-8.

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