JP6986225B2 - Paint repair products and paint repair methods - Google Patents

Description

The present invention relates to a coating repair product and a coating repair method.

As a method for repairing an externally defective portion of a coating due to foreign matter contamination or the like in a painted product such as a vehicle body coating of an automobile, for example, a method called blur coating as in Patent Document 1 and Patent Document 2 is known.

Patent Document 1 describes a repair coating method for metallic coating of an automobile body or the like, and uses aluminum flake pigment and a resin component as a coating composition used for blur coating that gradually spreads thinner as the distance from the repaired portion increases. Including, the average thickness of the aluminum flake pigment is in the range of 0.34 μm or less, the average particle size is in the range of 10 to 25 μm, and the content of the aluminum flake pigment based on the solid content mass of the resin component contained in this coating composition. A coating composition in which the amount is 5 to 40% by mass is described.

Patent Document 2 describes a repair coating method for an automobile body or the like, and in order to make the difference in finish between the repaired portion and the unrepaired portion inconspicuous, the coating film surface is repair-painted with an undercoat material and then this is applied. The undercoat paint is applied in advance to the entire coating surface including the repaired part, and then the water-based coloring base paint is applied so that the film thickness of the colored base coating formed on the repaired part is equal to or higher than the concealing film thickness. Moreover, it is described that the coating is blurred so that the film thickness of the colored base coating film formed on the unrepaired portion becomes thinner as the film thickness increases from the repaired portion.

On the other hand, in recent years, higher designability has been required for painting of automobiles and the like. For example, as in Patent Document 3, two layers of a highly concealing metallic base layer and a low concealing colored base layer are laminated. A so-called candy coating method, which has a vivid and deep color tone depending on the structure, is known.

In Patent Document 3, in a laminated coating film in which a specific color is produced by a metallic base layer and a color clear layer, the highlight reflectance of ^{a specific color is set to RH (P),} and a wavelength outside the hue range of the specific color is specified. When the average highlight reflectance of the region is ^{RH (OA)} , this laminated coating material ^{satisfies the equation (RH (P)} / ^{RH (OA)} )> 60. Is described.

Japanese Unexamined Patent Publication No. 2014-79674 Japanese Unexamined Patent Publication No. 2005-87877 Japanese Unexamined Patent Publication No. 2014-42892

Normally, the coating range of the blurred coating is hundreds of times, sometimes thousands of times larger than that of the defective part, and as the coating range of the blurred coating increases, the baking range of the blurred coating also increases. And the subsequent processing takes time. In particular, in the case of multi-layer coating such as the above-mentioned candy coating, it was found that a larger range of blur coating is required as compared with coating in which color is developed by only one layer of a standard base coat. For example, in order to bake a defective portion of a candy coating on an automobile body at a time, a large-sized drying facility that can accommodate one car body is required. Therefore, it takes a lot of time to repair the defective portion of the multi-layer coating, which is inefficient in mass production.

Further, the conventional blur painting is generally performed by a skilled technician. In particular, in the case of multi-layer coating such as the above-mentioned candy coating, if the range of blur coating is reduced or if a sudden change in coating film thickness occurs during blur coating, the floor The tone becomes poor and the repaired part can be easily seen. Therefore, in repairing the defective portion of the multi-layer coating, it is difficult to secure the finished state having the characteristics of the candy coating unless a more advanced skilled technician is used.

Further, the candy coating has an external feature that the color tone changes remarkably from the highlight side (near the reflected light side) to the shade side (shadow side away from the reflected light). This feature is due to the orientation of the bright material in the metallic base. Therefore, in order to maintain the characteristics of the candy coating even after the blur coating, it is important to reproduce the orientation of the bright material in the metallic base during the blur coating. Therefore, in repairing defective parts, it is difficult to secure a finished state having the characteristics of candy coating unless a person has advanced blur coating skills.

More specifically, when the paint of the metallic base coating film in the repair coating is made highly viscous, the bright material is difficult to be oriented and dust defects occur, and the bright material in the paint of the metallic base coating film is used. The orientation condition is sensitive to unstable factors such as season, weather fluctuation, paint gun distance, and film thickness, and there is a problem that the orientation is not stable throughout the year. Therefore, if the dilution ratio of the paint of the metallic base coating film is increased to lower the viscosity, the orientation will be stable, but it will be difficult to control the dilution process, etc., and if the dilution ratio is increased too much and the viscosity becomes extremely low, it will shine. There is a problem that the material is difficult to orient.

In view of the above problems, the present invention can easily maintain the characteristics of multi-layer coating such as candy coating even in repair coating by making it easy to stably orient the bright material of the metallic base paint for repair. It is an object of the present invention to provide a paint repair product and a paint repair method that can be performed.

In order to achieve the above object, the present invention, as one aspect thereof, surrounds a defective portion inside the coating product on the surface of the coating product, which is a coating repair product and includes a metallic base layer and a colored base layer. The metallic base on a repair undercoat coating and a repair undercoat coating that contains materials common to the metallic base layer, excluding the bright material or excluding the bright material and pigments, over the region. It comprises a metallic base coating for repair containing materials common to the layer.

It is preferable that the metallic base coating film for repair further contains a silica pigment.

It is preferable that the undercoat coating film for repair further contains a pigment.

The present invention is another aspect of the present invention, which is a method of painting and repairing a defective portion inside a painted product including a metallic base layer and a colored base layer, wherein a repair undercoat paint is applied to the surface of the painted product. The step of applying the undercoat paint for repair includes a step of applying the metallic base paint for repair containing a material common to the metallic base layer, following the application of the undercoat paint for repair, and the undercoat paint for repair. The metallic base paints for repair each contain a solvent having the same polarity.

The undercoat paint for repair is a paint in which the paint solid content is diluted to 8 to 13% by weight with a diluent, and the metallic base paint for repair has a paint solid content of 20 with a diluent. The paint is preferably diluted to ~ 35% by weight.

According to the present invention, the solvent content of the undercoat coating film is taken in by applying the metallic base paint for high viscosity repair before the solvent content of the undercoat coating film for low viscosity volatilizes. It is possible to stably orient the bright material even with a highly viscous metallic base paint.

(A) is a sectional view schematically showing a coated product having a defective portion to be repaired in one embodiment of the coating repair method according to the present invention, and (b) is a plan view thereof. It is sectional drawing which shows typically the coated article which sharpened in 1st step in one Embodiment of the coating repair method which concerns on this invention. (A) is a sectional view schematically showing a coated product cured in the second step in one embodiment of the coating repair method according to the present invention, and (b) is a plan view thereof. (A) is a sectional view schematically showing a coated product in which an undercoat coating film for repair is formed in a third step in one embodiment of the coating repair method according to the present invention, and (b) is a sectional view schematically showing. It is the plan view. (A) is a sectional view schematically showing a coated product in which a metallic base coating film for repair is formed in the fourth step in one embodiment of the coating repair method according to the present invention, and (b) is a sectional view schematically showing. It is the plan view. It is sectional drawing which shows typically the coated product which formed the coloring base coating film for repair in the 5th step in one Embodiment of the coating repair method which concerns on this invention. (A) is a sectional view schematically showing a coated product from which curing has been removed after the fifth step in one embodiment of the coating repair method according to the present invention, and (b) is a plan view thereof. (A) is a cross-sectional view schematically showing a coated product in which a colored blur base coating film for repair is formed in the sixth step in one embodiment of the coating repair method according to the present invention, and (b) is a sectional view schematically showing. , The plan view. (A) is a sectional view schematically showing a coated product in which a clear coating film for repair is formed in the seventh step in one embodiment of the coating repair method according to the present invention, and (b) is a sectional view thereof. It is a plan view. It is sectional drawing which shows typically the repair coating product obtained by firing and polishing in the 8th step in one Embodiment of the coating repair method which concerns on this invention.

Hereinafter, an embodiment of the painting repair method and the repaired painted product according to the present invention will be described with reference to the accompanying drawings. It should be noted that the drawings are not drawn according to the scale because the understanding of the invention is prioritized.

The coating repair method of the present embodiment includes a first step of polishing the surface of a coated product having a defective portion to be repaired, a second step of curing the periphery of the defective portion, and a repairing surface on the surface to be repaired. A third step of forming an undercoat coating film, a fourth step of forming a metallic base coating film for repair on the third step, a fifth step of forming a colored base coating film for repair on the third step, and curing. After removal, the sixth step of forming a coloring blur base coating film over a wider area, the seventh step of forming a clear coating film for repair on it, and the seventh step of firing the repair target and polishing the surface for repair. Includes an eighth step of obtaining a coated product.

[Paint gun]
As a coating gun for applying the paint used for forming various coating films in each of the above-mentioned 3rd to 7th steps, it is excellent in atomization even with a small discharge amount and excellent in pigment dispersibility. It is preferable to use an air atomizing spray gun that allows the formation of a continuous film. Further, from the viewpoint of narrowing the pattern range and smoothness of the coated surface, the coating nozzle preferably forms a round pattern and has a diameter of 0.3 mm to 0.6 mm. As a specific example of such a paint gun, there is a round blow gun equivalent to the trade name RG-3L series manufactured by Anest Iwata Co., Ltd., and it is sometimes called an airbrush.

[Repair target]
As shown in FIG. 1, the coated product 10 to be repaired in the present embodiment has an electrodeposition coating layer 12, an intermediate coating layer (base layer) 13, a metallic base layer 14, and a colored base layer on a base material 11. 15 and the clear coating layer 16 are provided in order. The base material 11 is, for example, a metal molded product such as an automobile or a two-wheeled vehicle, but may be a metal molded product for other purposes. As the metal molded product, for example, a metal base material such as a cold-rolled steel plate, a zinc-plated steel plate, a high-strength steel, an aluminum plate, and an aluminum alloy is preferable. It is also applicable to those in which a multi-layer coating film of a colored base layer is formed.

The electrodeposition coating layer 12 and the intermediate coating layer 13 are formed by a paint and a method generally used for coating automobiles and the like. For example, the electrodeposition coating layer 12 may be formed by a cationic electrodeposition coating material, and the intermediate coating layer 13 may be formed by an intermediate coating material containing a polycarbodiimide compound and a melamine resin as a curing agent.

The metallic base layer 14 is located on the deep side of the so-called candy coating, which is a multi-layer coating, and is a highly concealing layer containing a bright material. As the material for forming the metallic base layer 14, a known material for the metallic base layer may be used. For example, a material in which a bright material and a pigment are mixed with a resin for a base paint is used. As the resin for the base paint, for example, an acrylic resin, a polyester resin, an alkyd resin, a fluororesin, a urethane resin, a silicone-containing resin, a fibrous resin, or the like is used. These base paint resins may be used alone or in combination of two or more. These base paint resins may be organic solvent-based or water-based.

As the bright material, for example, aluminum flakes, vapor-deposited aluminum, colored aluminum, or the like may be used. Pigments include interfering mica pigments, white mica pigments, bright pigments such as graphite pigments, metal oxide pigments such as titanium oxide and iron oxide, composite metal oxide pigments such as titanium yellow, carbon black, azo pigments, and quinacridone pigments. Pigments, diketopyrrolopyrrole pigments, perylene pigments, perinone pigments, benzimidazolone pigments, isoindolin pigments, isoindolinone pigments, metal chelate azo pigments, phthalocyanine pigments, indanslon pigments, dioxane Coloring pigments such as system pigments and indigo pigments, and extender pigments such as clay, kaolin, barium sulfate, barium carbonate, calcium carbonate, talc, silica and alumina white may be used.

The blending amount of the bright material is not particularly limited, but is preferably in the range of 10 to 20% by weight, for example, 100% by weight of the resin for the base coating material. The blending amount of the pigment is not particularly limited, but is preferably in the range of 10 to 20% by weight, for example, 100% by weight of the resin for base paint. If necessary, a pigment dispersant, an ultraviolet absorber, a light stabilizer, polymer fine particles, a dispersion aid, a preservative, a silane coupling agent, an antifoaming agent, a curing catalyst, a viscosity modifier, an organic solvent, and neutralization. It may contain an additive for paint such as an agent.

In order to form the metallic base layer 14, the above-mentioned various materials of the metallic base layer are prepared into an organic solvent-based paint or a water-based paint dissolved and dispersed by an organic solvent or water, and applied to the surface of the intermediate coating layer 13 to form the metallic base layer 14. do.

The colored base layer 15 is located on the surface side of a multi-layer coating called candy coating, and is a semi-transparent or transparent layer having low hiding power. As the material for forming the colored base layer 15, a known colored base paint may be used, and for example, a material in which a pigment is mixed with a resin for a base paint is used. As the resin for the base paint, the same resin for the base paint as the metallic base layer 14 described above may be used. As the pigment, the same pigment as the metallic base layer 14 described above may be used. The blending amount of the pigment is not particularly limited, but is preferably in the range of 3 to 10% by weight, for example, the base paint resin is 100% by weight. If necessary, the same paint additive as the metallic base layer 14 may be contained.

In order to form the colored base layer 15, various materials of the colored base layer described above are prepared into an organic solvent-based paint or a water-based paint dissolved and dispersed with an organic solvent or water, and applied to the surface of the metallic base layer 14 to form the colored base layer 15. do.

The clear coating layer 16 is a transparent layer located on the outermost surface of the coated product 10. As the material for forming the clear coating layer 16, a known clear paint material may be used. For example, a curable paint containing an acrylic resin or a fluororesin as a main component and a polyisocyanate compound or the like as a curing agent, or cellulose acetate buty. Use a resin for clear paint such as lacquer paint whose main component is rate-modified acrylic resin. If necessary, a paint additive such as an ultraviolet absorber, a light stabilizer, a surface conditioner, and a curing catalyst may be contained.

In order to form the clear coating layer 16, various materials of the above-mentioned clear coating layer are prepared into an organic solvent-based paint or a water-based paint dissolved and dispersed with an organic solvent or water, and applied to the surface of the colored base layer 15 to form the clear coating layer 16. do. The layer thickness of the clear coating layer 16 varies depending on the desired coating performance, but is, for example, in the range of 25 to 40 μm.

[First step: Sharpening]
As shown in FIG. 1, the defective portion 17 that may occur in such a coated product 10 is often a case where foreign matter is mixed in the metallic base layer 14 or the colored base layer 15. Since the surface 16a of the clear coating layer 16 of the coating product 10 is raised at the defective portion 17 due to the inclusion of foreign matter, first, the surface 16a of the coating product 10 is sharpened. For sharpening, for example, polishing with sandpaper or the like is performed to smooth the surface.

The sandpaper count is preferably # 1200 or higher, and more preferably # 2000 to # 2500. With sandpaper of less than # 1200, the grain of the paper is coarse, making it difficult to form a smooth repair coating film for the coating film to be applied in the next step, and the metallic-based aluminum flake pigment is oriented along the polishing grain. This may result in the formation of a glaring coating film or a coating film that looks like streaks. On the other hand, sandpaper of # 3000 or more has poor polishing power, so that it takes a lot of time to polish.

The area to be polished is centered on the defective portion 17, and the surface 16a can be polished over a region having a substantially circular or substantially elliptical shape having a diameter of 10 to 100 times, more preferably 20 to 50 times the diameter of the defective portion 17. preferable. As shown in FIG. 2, the polishing depth is such that 10 to 100%, more preferably 20 to 40% of the layer thickness of the clear coating layer 16 is polished in the central portion of the area to be polished, and the polishing depth is gradually increased toward the outside. It is preferable to polish it so that it becomes shallow.

[Second step: Curing]
Next, as shown in FIG. 3, on the surface 16b of the coated product 10 after polishing, 1.2 to 5.0 times, more preferably 1.2, the diameter of the defective portion 17 centering on the defective portion 17. A polygonal or substantially circular or substantially elliptical region such as a quadrangle of ~ 1.5 times is left, and the periphery thereof is cured with a plurality of curing materials 21 such as solvent-resistant adhesive masking tape. If the area surrounded by the curing material 21 is less than 1.2 times the diameter of the defective portion 17, the defective portion 17 inside the coating may be visible at a watermark angle. On the other hand, if it exceeds 1.5 times, the repair range becomes large, the amount of the repair paint used increases, the energy required for firing the coating film increases, and the load on the environment increases, which is not preferable.

[Third step: Applying undercoat paint]
Then, as shown in FIG. 4, the undercoat paint is applied to the region surrounded by the curing material 21 with a coating gun to form the undercoat coating film 31. As the undercoat paint, it is preferable to use the material forming the metallic base base layer 14 described above (however, the bright material is excluded). As the resin for the base paint, any of the resins exemplified in the description of the metallic base base layer 14 can be used, and may be an organic solvent-based resin or an aqueous-based resin. Preferably, the undercoat paint is a metallic base paint used for forming the metallic base coating film 32 described later, from which the bright material and the pigment are removed. Further, as the undercoat paint, it is preferable to use a paint diluted with a diluent so that the solid content of the paint is, for example, 8 to 13% by weight, more preferably 9 to 11% by weight. As the diluent, for example, it is preferable to use a mixed organic solvent containing an aromatic hydrocarbon-based organic solvent, mainly an ester-based organic solvent such as ethyl acetate or butyl acetate.

Further, the undercoat paint may optionally contain a pigment. By blending the pigment, it is possible to solve the problem that the repair-painted part looks black from the shade side. As the pigment, for example, titanium oxide, white mica, other colored pigments and the like may be used. The blending amount of the pigment is preferably 5 to 30% by weight, more preferably 20 to 25% by weight, with the total solid content of the undercoat paint being 100% by weight.

The film thickness of the undercoat coating film 31 is preferably 2 to 5 μm, more preferably 2 to 3 μm. If the film thickness is less than 2 μm, it is difficult to form a continuous film, and the wettability of the metallic base paint to be formed in the next step is lowered, so that the orientation of the bright material such as aluminum flakes contained in the metallic base paint is lowered. There is a risk. Further, when the film thickness exceeds 5 μm, a plurality of coating films are formed on the film in the subsequent steps, so that the finally obtained repair coating film becomes too high and the surface of the coating film repair product is greatly convex. It is not preferable because it may have a shape.

[Step 4: Apply metallic base paint]
Further, as shown in FIG. 5, a metallic base coating film is applied onto the undercoat coating film 31 with a coating gun to form the metallic base coating film 32. As the metallic base paint, it is preferable to use the material forming the metallic base layer 14 described above. The resin for the base paint may be the same kind of resin as the metallic base base layer 14 or a different kind of resin, but it is preferable to use the same kind of bright material and pigment as the metallic base base layer 14. As the metallic base paint, it is preferable to use a paint diluted with a diluent so as to have a total paint solid content of, for example, 20 to 35% by weight, more preferably 25 to 30% by weight. As the base paint resin and diluent, it is preferable to use the same type of base paint resin and diluent as the undercoat paint.

The metallic base paint may increase the pigment weight concentration (PWC). PWC is calculated by the following formula. In this formula, the bright material is treated as a pigment.
PWC = [(weight% of pigment contained) / (% by weight of total paint solids)] × 100

The PWC of the metallic base paint is preferably 30 to 40% by weight, more preferably 30 to 35% by weight. The PWC of the organic solvent-based paint used to form the metallic base layer 14 is generally about 15 to 25% by weight, and by increasing the PWC in this way, the thickness of the metallic base coating film 32 is increased. Can be thinned.

When the metallic base paint is applied on the undercoat coating film 31, it is preferable to apply the metallic base paint before the solvent component of the undercoat paint volatilizes. This is because when the metallic base paint has a high viscosity, the bright material is difficult to orient, and it is sensitive to unstable factors such as season, weather fluctuation, paint gun distance, and film thickness, and it is sensitive to unstable factors such as film thickness throughout the year. Since the orientation is not stable, by applying a high-viscosity metallic base paint before the solvent content of the undercoat coating film 31 volatilizes as described above, the solvent content of the undercoat coating film 31 can be taken in and is stable. The bright material will be oriented.

A silica pigment may be further added to the metallic base paint. By adding the silica pigment, the orientation of the bright material after the flow of the bright material can be controlled and further stabilized. The blending amount of the silica pigment is preferably 0.5 to 8.0% by weight, more preferably 6.0 to 7.0% by weight, with the total solid content of the metallic base paint being 100% by weight.

The film thickness of the metallic base coating film 32 is a thickness that conceals the defective portion 17, and is preferably 4 μm or more, for example. If the film thickness is less than 4 μm, it is difficult to conceal the defective portion 17, and the color development may be poor. On the other hand, since the thickness of the finally obtained repair coating film is preferably as low as possible as described above, the film thickness of the metallic base coating film 32 is preferably 7 μm or less, more preferably 5 μm or less.

[Fifth step: Applying colored base paint]
Further, as shown in FIG. 6, a coloring base coating film 32 is applied on the metallic base coating film 32 with a coating gun to form the coloring base coating film 33. As the coloring base paint, it is preferable to use a material that forms the coloring base layer 15 described above. The resin for the base paint may be the same type of resin as the colored base layer 15 or a different type of resin, but it is preferable to use the same type of pigment as the colored base layer 15. As the coloring base paint, it is preferable to use a paint diluted with a diluent so that the total paint solid content is, for example, 20 to 35% by weight, more preferably 25 to 30% by weight. As the resin and diluent for the base paint, it is preferable to use the same kind of resin and diluent for the base paint as the undercoat paint and the metallic base paint. As the coloring base coating film 33, it is preferable to use an organic solvent-based coating film in which the whitening phenomenon of the coating film before drying is unlikely to occur in order to visually determine the completion of the film thickening. Further, the undercoat coating film 31, the metallic base coating film 32, and the coloring blur base coating film 34, which will be described later, are preferably of the same type, and therefore, they are also preferably organic solvent-based.

The coloring base paint may increase the pigment weight concentration (PWC). The PWC of the coloring base paint is preferably 5 to 25% by weight, more preferably 5 to 15% by weight. The PWC of the organic solvent-based paint used to form the coloring base layer 15 is generally about 3 to 10% by weight, and by increasing the PWC in this way, the thickness of the coloring base coating film 33 is increased. Can be thinned.

The film thickness of the coloring base coating film 33 is such that the hues of the repaired portion and the unrepaired portion match, and is preferably 3 μm or more, for example. If the film thickness is less than 3 μm, the color development is poor and the metallic base coating film 32 has an excessively strong sense of brightness, which may cause a sense of discomfort. On the other hand, the film thickness of the coloring base coating film 33 is preferably 6 μm or less, more preferably 4 μm or less. If the film thickness exceeds 6 μm, the color development is strong, the luminance feeling of the metallic base coating film 32 is lowered, and there is a possibility that a sense of discomfort may occur.

[Sixth step: Applying color blur base paint]
After forming the coloring base coating film 33, as shown in FIG. 7, all the curing material 21 is removed. As a result, the undercoat coating film 31, the metallic base coating film 32, and the coloring base coating film 33 are sequentially formed on the surface 16b of the coated product 10, and a laminated body having a wall surface 36 on the outer periphery can be obtained. Then, as shown in FIG. 8, the coloring blur base coating film is applied with a coating gun over the surface 16b of the coating product 10 on the outer peripheral side of the wall surface 36 and the surface of the coloring base coating film 33, and the coloring blur base coating film is applied. Form 34.

As the coloring blur base coating material, the material forming the coloring base coating film 33 described above can be used. For example, the coloring base coating material used for forming the coloring base coating film 33 has a pigment content of the coloring base coating material 33. The resin solid content contained in the above is 100% by weight, preferably 0.2 to 2.0% by weight, and more preferably 0.2 to 1.0% by weight. If the pigment content is less than 0.2%, the coloring power is poor and the amount of the paint used for coloring increases, which is not preferable in terms of cost. On the other hand, if it exceeds 2.0%, the coloring power becomes too strong, and the gradation of the coloring blur base coating film 34 formed on the outer peripheral side of the wall surface 36 becomes poor, which is not preferable.

As described above, the surface 16b of the coated product 10 is polished so that the defect portion 17 is the deepest and gradually becomes shallower toward the outside around the defect portion 17, so that the colored blur base coating film 34 is a wall surface. It is configured so that the film thickness gradually decreases from 36 toward the outside. The film thickness of the coloring blur base coating film 34 is preferably 3 to 10 μm, more preferably 5 to 8 μm on the surface of the coloring base coating film 33. At a position adjacent to the wall surface 36, the height needs to be at least higher than the height of the metallic base coating film 32, for example, 12 to 28 μm is preferable, and 14 to 20 μm is more preferable. The planar shape of the color blur base coating film 34 is preferably substantially circular or substantially elliptical.

[7th step: application of clear paint]
Further, as shown in FIG. 9, a clear paint is applied with a coating gun on the surface of the color blur base coating film 34 and over the surface 16b of the coating product 10 on the outer periphery thereof, and the clear coating film is the uppermost layer of the repair coating. Form 35. As the resin for clear paint, acrylic resin, polyester resin, urethane resin, epoxy resin and the like are used. It is preferable that the clear paint is gradually and thinly spread radially outward from the center, but since the clear paint film has no gradation, the gradual decrease in the film thickness does not have to be strict. The planar shape of the clear coating film 35 is preferably substantially circular or substantially elliptical.

[8th step: firing]
After the clear coating film 35 is formed, the entire coating film formed in the above third to seventh steps is fired and cured. Then, the surface 35a of the clear coating film 35 is polished with a compound or the like and polished to obtain a smooth surface 35b as shown in FIG.

As shown in FIG. 10, the repair coated product thus obtained has an undercoat coating film 31, a metallic base coating film 32, and a colored base coating film 33 over a region including a defective portion 17 on the above-mentioned coated product surface 16b. Are laminated in order, and each of these coating films has a wall surface 36 on the outer periphery. Further, a coloring blur base coating film 34 is formed over the outer peripheral side surface 16a of the wall surface 36 and the surface of the coloring base coating film 33, and a clear coating film 35 is further formed on the colored blur base coating film 34. The film thickness of the coloring base coating film 34 is substantially uniform on the surface of the coloring base coating film 33, and is thicker than the thickness from the surface 16b to the coloring base coating film 33 at a position adjacent to the wall surface 36, and is outside the thickness. It is getting thinner toward.

According to the painting repair method having the above steps, the range of repair painting can be minimized and the range of repair painting can be minimized by curing with the curing material 21 so that the paint does not get on the parts that do not need to be repaired. Since the paint is applied in a predetermined amount (target film thickness), it does not require a high level of skill as in conventional blur painting. Specifically, by specifying the gun distance, the discharge amount, and the spray time without moving the gun tip of the paint gun, it is possible to perform the operation even if the person is not a skilled technician. Further, the range of the repair coating is narrow, and the repair coating film can be fired at one time. Therefore, compared to the conventional blur repair method, the amount of paint used for repair painting can be significantly reduced to a few tenths, and the time required for repair painting is about half or less. Can be significantly reduced.

Due to the above curing, the wall surface 36 exists on the outer periphery of the two layers composed of the metallic base coating film 32 and the coloring base coating film 33, and when the repair surface is viewed from the vertical direction as shown in the position 40c of FIG. Although the hue matches that of the unrepaired portion, the wall surface 36 portion of the metallic base coating film 32 stands out white when viewed from an oblique direction, as shown at positions 40a and 40b in FIG. 10, but at least the metallic base coating film is conspicuous. By forming the colored blur base coating film 34 so as to cover the outer peripheral wall surface of 32, the wall surface 36 is colored, and the wall surface portion of the metallic base coating film can be made inconspicuous even when viewed from an oblique direction.

Further, the coloring blur base coating film 34 has a lower pigment concentration than the coloring base coating film 33. This is because when the coloring blur base coating film 34 contains the pigment at the same concentration as the coloring base coating film 33, the coloring blur base coating film 34 is thickly formed in the region around the wall surface 36, so that the saturation is achieved. Therefore, the occurrence of such darkening can be prevented by lowering the concentration of the pigment in the coloring blur base coating film 34 and minimizing the color development. At the same time, the effect of leveling the edge angle of the wall surface 36 can be obtained.

When repairing a two-layer coating such as so-called candy coating, the repair coating film also has at least a two-layer structure, so that the film thickness of the repair coating film is thicker than before. If the film thickness of the repair coating film becomes too thick, the surface of the repair coating film may be greatly raised, or the repair coating film may be scraped off when smoothed, resulting in a mismatch in hue. By making the pigment weight concentration (PWC) of both the metallic base coating film 32 and the coloring base coating film 33 higher than the PWC of the respective paints of the metallic base layer 14 and the coloring base layer 15, the metallic base coating film 32 and Even if the film thickness of the coloring base coating film 33 is reduced, the desired functions can be exhibited, so that the entire repair coating film can be thinned.

Further, in the repair of candy coating, it is important to reproduce the orientation of the bright material before the repair. However, if the paint of the metallic base coating film 32 has a high viscosity, the bright material is difficult to orient and dust defects occur. And the orientation condition of the bright material in the paint of the metallic base coating film 32 is sensitive to unstable factors such as season, weather fluctuation, coating gun distance, film thickness, etc., and the orientation is all year round. There is a problem of instability. Therefore, if the dilution ratio of the paint of the metallic base coating film 32 is increased to lower the viscosity, the orientation is stable, but it is difficult to control the dilution process, etc., and if the dilution ratio is increased too much and the viscosity becomes extremely low, There is a problem that the bright material is difficult to orient. Therefore, by applying the high-viscosity metallic base paint before the solvent content of the undercoat coating film 31 volatilizes, the solvent content of the undercoat coating film 31 can be taken in, and the high-viscosity metallic base paint is used. It is also possible to stably orient the bright material.

Further, under the two layers of the metallic base layer 14 and the colored base layer 15 that express the candy coating, the base of the intermediate coating layer 13 is coated to ensure the brightness. On the other hand, since the two layers of the metallic base coating film 32 and the coloring base coating film 33 corresponding to the above are painted on the surface 16b of the coated product 10, they are on the full shade side (the shadow side away from the reflected light). When viewed from the side substantially parallel to the coating film (further from the coating film side than the position 40b in FIG. 10), only the portion applied to the repair coating film has low brightness and appears darkened. Therefore, by blending the pigment in the undercoat coating film 31 located under the metallic base coating film 32, the problem of appearing black from the shade side can be solved.

10 Painted product 11 Base material 12 Electrodeposition coating layer 13 Intermediate coating layer 14 Metallic base layer 15 Colored base layer 16 Clear coating layer 17 Defects 21 Curing material 31 Undercoat coating film 32 Metallic base coating film 33 Coloring base coating film 34 Coloring Blur base coating film 35 Clear coating film 36 Wall surface

Claims (5)

On the surface of the coated product including the metallic base layer and the colored base layer, over the region surrounding the metallic base layer or the defective portion generated in the colored base layer inside the coated product.
Except for the luminous material or except luminous material and pigment seen containing a material common to the metallic base layer, and undercoat coating for repair of thickness 2 to 5 [mu] m,
On the repair undercoat coating film, a metallic base coating film for repair containing a material common to the metallic base layer, and
On the metallic base coating film for repair, a coloring base coating film for repair containing a material common to the coloring base layer is provided, and the undercoat coating film for repair and the metallic base coating film for repair are provided. And the colored base coating film for repair form a laminated body having a wall surface on the outer periphery, and further.
A coloring blur base coating film for repair containing a material common to the coloring base layer on the surface of the coloring base coating film for repair and on the surface of the coated product on the outer peripheral side of the wall surface.
On the surface of the colored blur base coating film for repair and on the surface of the coated product on the outer periphery thereof, a clear coating film for repair
Paint repair products Ru equipped with. The coating repair product according to claim 1, wherein the metallic base coating film for repair further contains a silica pigment. The coating repair product according to claim 1 or 2, wherein the undercoat coating film for repair further contains a pigment. It is a method of painting and repairing a defective portion generated in the metallic base layer or the colored base layer inside the coated product including the metallic base layer and the colored base layer.
The first step of polishing the surface of the painted product having the defective portion to be repaired, and
The second step of curing the periphery of the defective portion and
On the surface of the coated product, and a third step of applying an undercoat paint for repairing,
Following the application of the undercoat paint for repair, a fourth application of the metallic base paint for repair containing a material common to the metallic base layer before the solvent component of the undercoat paint for repair volatilizes. and a step,
Following the application of the metallic base paint for repair, a fifth step of applying the colored base paint for repair containing a material common to the colored base layer, and
After removing the curing to obtain a laminate having a wall surface on the outer periphery in which an undercoat coating film for repair, a metallic base coating film for repair, and a colored base coating film for repair are sequentially formed, the wall surface is covered. A sixth step of applying a colored blur base paint containing a material common to the colored base layer over the surface of the coated product on the outer peripheral side and the surface of the colored base coating film.
The seventh step of applying the clear paint for repair on the surface of the colored blur base coating film for repair and over the surface of the painted product on the outer periphery thereof.
A coating repair method comprising the eighth step of firing the repair target and polishing the surface to obtain a repair coating product , wherein the repair undercoat paint and the repair metallic base paint each contain a solvent having the same polarity. .. The undercoat paint for repair is a paint in which the paint solid content is diluted to 8 to 13% by weight with a diluent, and the metallic base paint for repair has a paint solid content of 20 with a diluent. The coating repair method according to claim 4, wherein the coating material is diluted to ~ 35% by weight.

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