JP2006143757A - Water-based colored coating, coated material and method for producing coated material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a water-based colored coating that makes a colored layer of a deep color or white color (color closely resembling a white color), has excellent interlayer adhesivity between a colored layer and a clear layer and controls cohesive failure of a colored layer, a coated material and to provide a method for producing a coated material. <P>SOLUTION: The method for producing a coated material comprises, firstly in a coloring process, coating the surface of a substrate with a water-based colored coating that is a water-based colored coating comprising a photocurable water-based resin, a colored solid component and a photoinitiator, contains ≥12 wt.% of the colored solid component in a coating component obtained by removing the photoinitiator from the water-based colored coating in which the photocurable water-based resin has ≥1,000 average molecular weight and ≤100°C lowest film-forming temperature and removing water by hot drying without irradiation with light to cleave the photoinitiator so as to form a colored layer and then, in a clear layer forming process, coating the surface of the colored layer with a clear coating containing a photocurable resin and photo-curing the clear coating to form a clear layer. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a water-colored paint, a coated product using the water-colored paint, and a method for producing a coated product using the water-colored paint.

In recent years, in order to reduce environmental pollution and improve the working environment, there is an increasing demand for water-based colored paints that do not use solvents. For this reason, in recent years, various methods have been proposed for water-based colored paints, coated products using water-based colored paints, and methods for producing coated products using water-based colored paints. (For example, refer to Patent Document 1 and Patent Document 2).
JP-A-10-273608 JP 2000-109741 A

Patent Document 1 discloses the following example. First, 100 parts by weight of a photocurable resin (polyethylene glycol diacrylate), 13.5 parts by weight of a water dispersion colorant, 5.0 parts by weight of a photosensitizer, and water are mixed to contain a solid content. An aqueous colored paint having a rate of 50% by weight is prepared. Then, after applying 0.4 to 0.6 g / (30 cm) ^{2 of} this aqueous colored paint on the surface of the base material, the aqueous colored paint is photocured by irradiating ultraviolet rays at 170 to 210 (mJ / cm ² ). . Next, after applying a photocurable clear coating (unsaturated polyester), the clear coating is photocured by irradiating with ultraviolet rays at 260 to 320 (mJ / cm ² ). As described above, in Patent Document 1, after a water-based colored paint is photocured, a clear paint is applied and photocured to produce a coated product.

  Further, in Patent Document 2, in order to improve the coloring of the hydrophobic portion of the porous member, as a component of the aqueous coloring paint, a powder of a fibrous magnesium silicate mineral that is a thixotropic thickener (specifically, Has added a fibrous apatal gite powder). The powder of the fibrous magnesium silicate minerals is most preferably added in a proportion of 1 to 10% by weight in the aqueous coloring paint, and within this range, the hydrophobic part of the porous member increases as the addition amount increases. The result that the coloring to is favorable is obtained.

However, as in Patent Document 1, in the method of applying the clear paint after photocuring the aqueous colored paint, the application amount per unit area of the aqueous colored paint is increased (for example, 3.0 g / (30 cm)). ^{In 2} ), even if the aqueous colored paint is irradiated with ultraviolet rays, it may be difficult to sufficiently cure the aqueous colored paint. For this reason, there was a risk of causing cohesive failure of the colored layer. Furthermore, when the amount of ultraviolet light is increased to appropriately cure the water-based colored paint, the surface of the colored layer is excessively photocured, and this time, delamination occurs between the colored layer and the clear layer. There was a risk of getting lost.

  Moreover, in patent document 2, it will become difficult to form a water-based colored coating film by adding the powder of fibrous magnesium silicate minerals. For this reason, there was a risk that the formation of the coating film of the water-based colored paint was hindered and the colored layer was agglomerated and broken.

  On the other hand, the present inventor uses an aqueous colored paint containing a photocurable aqueous resin having an average molecular weight of 1000 or more and a minimum film forming temperature of 100 ° C. or less and a water-dispersed colorant as the aqueous colored paint. Thus, it has been found that the above problems can be solved (see Japanese Patent Application No. 2004-126337). Specifically, the water-based colored paint is applied to the surface of the substrate, and moisture is removed by heat drying without irradiating with ultraviolet rays to form a colored layer. Next, a clear paint containing a photocurable resin is applied to the surface of the colored layer, and photocured by ultraviolet irradiation to form a clear layer. It has been found that by such a technique, the interlayer adhesion between the colored layer and the clear layer is improved and cohesive failure of the colored layer can be suppressed.

  By the way, in recent years, as a wood material used for a house or the like, the demand for a dark or white wood material whose surface finish (color tone) is increasing. In order to meet this requirement, a painted product was manufactured using a dark or white water-based colored paint by the above-mentioned method found by the present inventor (see Japanese Patent Application No. 2004-126337). It has been found that the effect of suppressing the cohesive failure of the colored layer is reduced as compared with the case where a paint is used.

  This is thought to be due to the addition of a large amount of water-dispersed colorant in the aqueous colored paint compared to other colors in order to make the colored layer (aqueous colored paint) dark or white. It is done. That is, by increasing the proportion of colored solids (colored pigments and dyes) contained in the aqueous colored paint, the proportion of the aqueous resin contained in the aqueous colored paint is reduced and other components (colored solids) due to the aqueous resin are reduced. Etc.) is considered to be a major factor.

  The present invention has been made in view of such problems, and the colored layer can be dark or white (including a color approximating white), and the interlayer adhesion between the colored layer and the clear layer. An object of the present invention is to provide a water-based colored paint, a coated product, and a method for producing the coated product, which are good and can suppress cohesive failure of the colored layer.

  The solution is an aqueous coloring paint containing a photocurable water-based resin, a colored solid, and a photoinitiator, wherein the coloring is contained in a paint component obtained by removing the photoinitiator from the aqueous coloring paint. The photocurable aqueous resin containing a solid content of 12 wt% or more is an aqueous colored paint having an average molecular weight of 1000 or more and a minimum film forming temperature of 100 ° C. or less.

The colored paint of the present invention is an aqueous colored paint. For this reason, it is the paint which considered environmental pollution reduction and work environment enough.
Furthermore, in the paint component obtained by removing the photoinitiator from the aqueous colored paint, 12 wt% or more of a colored solid content (colored pigment or dye) is included. If a colored layer is formed using a colored paint containing a colored solid content at such a ratio, the colored layer can be appropriately dark or white. In particular, white (including a color approximating white) is difficult to develop, but if a colored layer is formed using a colored paint containing a colored solid at the above ratio, the colored layer is appropriately white (approximate to white). Color).

Furthermore, the water-based colored paint of the present invention contains a photocurable aqueous resin having a minimum film-forming temperature (hereinafter also referred to as MFT) of 100 ° C. or less. For this reason, a coating film can be formed only by applying the water-based colored paint of the present invention to the surface of a substrate and drying it by heat (water removal).
Furthermore, since the average molecular weight of the photocurable aqueous resin is 1000 or more, the coating surface can be brought into a tack-free state when the aqueous colored coating applied to the substrate surface is dried (moisture removal). Therefore, a photocurable clear coating can be appropriately applied on the colored layer without irradiating light such as ultraviolet rays to photocur the colored coating (colored layer).

  Further, when the clear paint is photocured, the clear layer and the colored layer can be brought into close contact with each other. This is because the colored layer is not photocured, so there are many unreacted functional groups on the surface. When the clear paint is irradiated with light such as ultraviolet rays, the resin (molecules) on the surface of the colored layer This is probably because the resin (molecule) of the clear paint reacts and binds.

  Moreover, the water-based colored paint of the present invention contains a photoinitiator in addition to the photocurable resin. For this reason, when the clear paint applied on the colored layer is irradiated with light such as ultraviolet rays, it is possible to photocur the photocurable resin in the colored layer by the action of the photoinitiator in the colored layer. Become. Specifically, since the water-based colored paint of the present invention contains 12 wt% or more of colored solids (colored pigments and dyes), the colored layer becomes dark or white, but light (such as ultraviolet rays) is applied to the clear paint. The colored layer can also be photocured to some extent when irradiated. Thereby, the cohesive failure of a colored layer can be suppressed.

  In addition, MFT of photocurable aqueous resin can be measured using a well-known MFT measuring apparatus. Examples of the MFT measuring device include TP-801 MFT tester (trade name, manufactured by Tester Sangyo Co., Ltd.). In this apparatus, a photocurable aqueous resin as a sample is placed on a stainless steel substrate, the temperature of the substrate is fluctuated (increased), and the temperature when the photocurable aqueous resin is whitened or cracked is determined as MFT. Can be measured as

  The average molecular weight of the photocurable aqueous resin can be measured using a known average molecular weight measuring apparatus. Examples of the average molecular weight measuring device include a high-speed GPC device HLC-8220G (trade name, manufactured by Tosoh Corporation). In this apparatus, a photocurable aqueous resin dissolved in a solvent such as THF (tetrahydrofuran) is used as a sample, and the average molecular weight of the aqueous resin can be measured based on the molecular weight distribution peak of this sample.

  Examples of the photocurable aqueous resin include resin solids (specifically, urethane acrylate) contained in Laromar LR8949, Laromar LR8983, Laromar LR9005 (trade name, manufactured by BASF). .

Moreover, as a colored solid content, a known water-dispersible color pigment or a water-soluble dye can be used. The colored solid content may be any of organic matter, inorganic matter, natural product, and synthetic product. The colored solids can be used alone or in combination of two or more.
Examples of the water-dispersible color pigment include titanium oxide, carbon black, naphthol red, disazo yellow, phthalocyanine blue, phthalocyanine green, and a petal.
Examples of water-soluble dyes include Direct Scarlet, Direct Orange R, Direct Fast Orange WS, Clinphenine G, Direct Dark Green B, Direct Brown KGG, Direct Blue BB, Direct Black EX, Roselin, Acid Azorubin, Acid Examples include Orange B, Methanil Yellow, Brilliant Milling Green B, Acid Brown R, and Acid Blue Black 10B.

  Furthermore, the water-based colored paint described above may be a water-based colored paint containing less than 30 wt% of the colored solid content and other inorganic substances in the paint component obtained by removing the photoinitiator from the water-based colored paint. .

  On the other hand, if the ratio of the colored solid content contained in the water-based colored paint is too large, the ratio of the photocurable water-based resin will be too small. Therefore, even if the water-colored paint (colored layer) is photocured. The film strength (cohesive force) of the colored layer is weak and there is a risk of cohesive failure. Also, as the proportion of the colored solid content in the water-based colored paint is increased, the viscosity of the water-colored water-based paint becomes too large as the proportion of the photocurable aqueous resin is increased. There is a possibility that gelation will progress with the passage of time, making it impossible to paint properly.

  On the other hand, in the water-based colored paint of the present invention, in the paint component obtained by removing the photoinitiator from the water-colored paint, the combined color solids and other inorganic substances are limited to less than 30 wt%. Thereby, since a photocurable water-based resin can be contained in an appropriate ratio in the water-based colored paint, there is no possibility that the above-described problems occur, and the coating can be appropriately performed. Furthermore, since the colored layer which has moderate film | membrane intensity | strength (cohesive force) can be formed by photocuring this, the cohesive failure of a colored layer can be suppressed.

Other inorganic substances include extender pigments and powders of fibrous magnesium silicate minerals. Further, the colored solid content may be any of organic, inorganic, natural and synthetic products as described above.
In addition to the colored solid content, the aqueous colored paint of the present invention also includes an aqueous colored paint that does not contain inorganic substances such as extender pigments. In this case, the colored solid content may be less than 30 wt%.

  Furthermore, in any one of the above-mentioned water-based colored paints, the weight W1 of the colored solid content and other inorganic substances combined with the weight W2 of the photocurable water-based resin is 0.12 <W2 / W1 <1. It is good that it is a water-based coloring paint satisfying the relationship of 2.

  If the ratio of the photocurable aqueous resin is made too small relative to the ratio of the colored solid content in the aqueous colored paint, the film strength (cohesive strength) of the colored layer will be increased even if the aqueous colored paint (colored layer) is photocured. It is weak and has a risk of cohesive failure. On the other hand, in the water-based colored paint of the present invention, the color solid content and other inorganic substances, the photocurable water-based resin, and the weight ratio satisfy the relationship of W2 / W1> 0.12. As described above, when the photocurable aqueous resin is contained in an amount larger than 0.12 times (by weight) of the colored solid and other inorganic substances, an appropriate film strength (cohesive force) can be obtained when photocured. A colored layer can be formed. Therefore, cohesive failure of the colored layer can be suppressed.

On the other hand, if the ratio of the photocurable water-based resin is too large, the viscosity of the water-based colored paint becomes too large, and further, the storage stability is lowered, and gelation proceeds with the passage of time. There is a risk that it may become impossible to paint. On the other hand, the water-based colored paint of the present invention satisfies the relationship of W2 / W1 <1.2. In this way, by limiting the ratio of the photocurable water-based resin, there is no possibility that the above-described problems occur, and the water-based colored paint can be appropriately applied.
The aqueous colored paint of the present invention includes an aqueous colored paint that does not contain inorganic substances such as extender pigments in addition to the colored solid content. In this case, the weight of the colored solid content is W1.

Furthermore, in the above-mentioned water-based colored paint, the weight W1 of the colored solid content and other inorganic substances combined with the weight W2 of the photocurable aqueous resin satisfies the relationship of W2 / W1> 0.18. It is preferable that it is the water-based coloring paint.
By setting W2 / W1> 0.18, the cohesive failure of the colored layer can be further suppressed.

  Furthermore, it is any of the above-mentioned water-based colored paints, and is a water-based colored paint containing 0.15 parts by weight or more of the photoinitiator with respect to 100 parts by weight of the paint component obtained by removing the photoinitiator from the water-based colored paint. And good.

By containing the photoinitiator at such a ratio, the water-based colored paint can be appropriately photocured.
Examples of the photoinitiator include 2-hydroxy-2-methyl-1-phenylpropan-1-one, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, 4- Benzoyl-N, N-dimethyl-N- (2- (1-oxo-2-propenyloxy) ethyl) benzenemethananium bromide, (4-benzoylbenzyl) trimethylammonium chloride, 2-hydroxy-3- (4- Benzoylphenoxy) -N, N, N-trimethyl-1-propanaminium chloride, 2-hydroxy-3- (3,4-dimethyl-9-oxo-9H-thioxanthen-2-yloxy) -N, N, N-trimethyl-1-propanaminium chloride and the like can be mentioned.

  Furthermore, in any of the above-described water-based colored paints, the photoinitiator may be a water-based colored paint that is a visible light-cleavable photoinitiator that can be cleaved by visible light.

  By using a visible light cleavage type photoinitiator, ultraviolet rays or visible light having a long wavelength (wavelength close to visible light) or visible light can be used in order to cure the aqueous coloring paint. For this reason, even when a large amount of colored solids (colored pigments and dyes) is contained, as in the case of the water-based colored paint of the present invention, light easily reaches the inside of the coating film (colored layer) of the water-based colored paint. Become. Therefore, the colored layer can be appropriately photocured. Examples of the visible light cleavage type photoinitiator include Darocur 4265 (trade name, manufactured by Ciba Specialty Chemicals), Lucyrin TPO-L (trade name, manufactured by BASF), and the like. Darocur 4265 is an initiator containing 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide and 2-hydroxy 2-methyl 1-phenyl-propan-1-one in a ratio of 1: 1. Lucillin TPO-L is an initiator composed of 2,4,6-trimethylbenzoyl-phenyl-ethoxyphosphine oxide.

  Furthermore, it is any one of the above-mentioned water-based colored paints, and the photocurable water-based resin preferably has an average molecular weight of 1600 or more and 15000 or less.

  In the water-based colored paint of the present invention, the average molecular weight of the photocurable aqueous resin is 1600 or more and 15000 or less. For this reason, a tack-free colored layer can be suitably formed simply by applying the water-based colored paint of the present invention to the substrate surface and then drying (removing water). Therefore, a photocurable clear coating can be suitably applied on the colored layer without using a light such as ultraviolet rays to photocure the colored coating (colored layer).

  Furthermore, it is any of the above-mentioned water-based colored paints, and the minimum film-forming temperature of the photocurable aqueous resin is preferably a water-based colored paint having a temperature of 60 ° C. or less.

  Since the minimum film-forming temperature (MFT) of the photocurable aqueous resin is set to 60 ° C. or less, it is possible to appropriately form a coating film simply by applying this aqueous colored paint to the substrate surface and drying (removing moisture). it can.

  Furthermore, it is any of the above-mentioned water-based colored paints, and the minimum film-forming temperature of the photocurable aqueous resin is preferably a water-based colored paint having a temperature of 0 ° C. or lower.

  In the water-based colored paint of the present invention, the minimum film-forming temperature (MFT) of the photocurable aqueous resin is 0 ° C. or less. For this reason, a coating film can be reliably formed only by apply | coating the water-based coloring paint of this invention to the base-material surface, and making it dry (moisture removal).

  Furthermore, in any one of the above-mentioned water-based colored paints, the photocurable water-based resin is preferably a water-based colored paint having an average molecular weight of 2500 or more and a minimum film forming temperature of 0 ° C. or less.

  In the water-based colored paint of the present invention, a photocurable aqueous resin having an average molecular weight of 2500 or more and a minimum film forming temperature of 0 ° C. or less is used. For this reason, after applying the water-based colored paint of the present invention to the surface of the substrate, it is possible to form a colored layer that is suitably dried and cured in a tack-free state by simply drying (removing moisture).

  Furthermore, it is preferable that it is said aqueous coloring coating material, Comprising: It is an aqueous coloring coating material containing the thickener which has thixotropic property.

  The aqueous coloring paint of the present invention contains a thickener having thixotropic properties. For this reason, the filling coating in the recessed part (For example, the conduit | pipe part of a wooden base material etc.) of a base-material surface becomes favorable. Furthermore, since there is little possibility of the paint flowing before curing after coating, it is possible to increase the coating amount per unit area and form a thick colored layer.

  Furthermore, in the above-described aqueous coloring paint, the thixotropic thickener is preferably an associative aqueous coloring paint.

By using an associative thickener as the thixotropic thickener, the binding with other molecules in the water-colored paint becomes relatively good, so that the water-colored paint can be appropriately dried and cured. For this reason, it is possible to reduce the risk of cohesive failure of the colored layer while improving the filling coating in the recesses on the surface of the base material (for example, the conduit portion of the wood base material).
Examples of associative and thixotropic thickeners include Primal RM-12W (Rohm & Haas, trade name), Rheorate 288 (Rheox, trade name) and the like.

  Further, any one of the above-mentioned water-based colored paints, preferably a water-based colored paint containing a thickener having a Newtonian viscosity or a viscosity close thereto.

  The aqueous coloring paint of the present invention contains a thickener having a Newtonian viscosity or a viscosity close thereto. For this reason, the fluidity of the water-based colored paint becomes good, and transfer coating onto a flat portion of the substrate surface becomes possible. The Newtonian viscosity is a property that the viscosity does not change without being affected by a change in external load. Therefore, the paint having a Newtonian viscosity has good fluidity.

  Furthermore, in the above-mentioned water-based colored paint, the thickener having a Newtonian viscosity or a viscosity close thereto is preferably an association-type water-colored paint.

By using an associative thickener with a Newtonian viscosity or a viscosity close to this, the binding with other molecules in the water-colored paint becomes relatively good, so the water-colored paint is properly dried. It can be cured. For this reason, the risk of cohesive failure of the colored layer can be reduced while improving the fluidity of the water-based colored paint.
In addition, as an association type thickener having a Newtonian viscosity or a viscosity close thereto, for example, Primal RM-8W, Primal RM-825, and Primal RM-2020NPR (above, manufactured by Rohm & Haas Co., Ltd., trade name) And Rheorate 350 (trade name, manufactured by Rheox).

  Other solutions include a base material, a colored layer obtained by photo-curing any of the above-mentioned aqueous colored paints applied to the surface of the base material, and a photocurable resin applied to the surface of the colored layer. A clear layer obtained by photocuring a clear coating containing, and a molecule constituting the photocurable aqueous resin of the colored layer and a molecule constituting the photocurable resin of the clear layer are bonded to each other. A coated product in which the colored layer and the clear layer are in close contact with each other.

  The coated product of the present invention has a colored layer formed using an aqueous colored paint containing 12 wt% or more of a colored solid content (colored pigment or dye) in the paint component obtained by removing the photoinitiator from the aqueous colored paint. Yes. For this reason, the colored layer (coating surface) of the coated product of the present invention is dark or white. Furthermore, since this colored layer is photocured, even if it contains a large amount of solid paint as described above, it has an appropriate film strength (cohesive force). Therefore, in the coated product of the present invention, there is little possibility that the colored layer will cohesively break.

  Furthermore, the molecule | numerator which comprises the photocurable water resin of a colored layer, and the molecule | numerator which comprises the photocurable resin of a clear layer couple | bond together, and the colored layer and the clear layer have adhered. For this reason, the risk of delamination between the colored layer and the clear layer is extremely reduced in the coated product of the present invention.

  In addition, as a base material of the coated material of this invention, the plastic molded product, a plastic film, and a plastic sheet which consist of a polyvinyl chloride, an acrylic resin, a polyethylene terephthalate, a polycarbonate, an ABS resin etc. are mentioned, for example. Moreover, wood materials, such as a single board, a plywood, a particle board, a hard board, and MDF, are mentioned. Further, rubber molded products and rubber sheets made of SBR, EPM, urethane and the like can be mentioned. Moreover, sheet-like base materials, such as cloth and paper, metal molded products, such as a can and a locker, metal plates, such as a precoat metal steel plate, etc. are mentioned.

  In addition, the coated object of the present invention can be used as a material for electric and electronic devices such as a mobile phone, a wristwatch, a compact disc, an audio device, and an OA device. Moreover, it can be used as an electronic material component such as a touch panel or an antireflection plate of a cathode ray tube. Moreover, it can use as a material of household appliances, such as a refrigerator, a vacuum cleaner, a microwave oven, and a lighting fixture. Further, it can be used as an automobile interior material such as an automobile meter panel and a dashboard. It can also be used as automotive parts such as bodies, bumpers, spoilers, door knobs, handles, headlamps, motorcycle gasoline tanks, aluminum wheels with plating / deposition / sputtering, and door mirrors. Moreover, it can be used as a material for woodwork products such as furniture such as stairs, floors, tables, desks, chairs and chiffons. Moreover, it can be used as a roofing material for carports or a lighting roofing material.

  Another solution is an aqueous colored paint containing a photocurable aqueous resin, a colored solid, and a photoinitiator, wherein the colored solid is contained in a paint component obtained by removing the photoinitiator from the aqueous colored paint. 12 wt% or more of the above, the photocurable aqueous resin has an average molecular weight of 1000 or more and a minimum film-forming temperature of 100 ° C. or less applied to the surface of the substrate without photocuring, Water is removed by heat drying to form a colored layer, and a clear paint containing a photocurable resin is applied to the surface of the colored layer, and photocured with the colored layer to form a clear layer. And a clear layer forming step.

  In the method for producing a coated product of the present invention, in the coloring step, an aqueous colored paint containing 12 wt% or more of a colored solid content (colored pigment or dye) is applied to a paint component obtained by removing the photoinitiator from the aqueous colored paint. If a colored layer is formed using a colored paint containing a colored solid content at such a ratio, the colored layer can be appropriately darkened. In particular, white (including a color approximating white) is difficult to develop, but if a colored layer is formed using a colored paint containing a colored solid at the above ratio, the colored layer is appropriately white (approximate to white). Color).

  Furthermore, this water-based colored paint contains a photocurable aqueous resin having a minimum film-forming temperature of 100 ° C. or lower. For this reason, a coating film can be formed only by heat drying (moisture removal) without irradiating light such as ultraviolet rays (photocuring). Furthermore, since the average molecular weight of the photocurable water-based resin is 1000 or more, a tack-free colored layer can be formed simply by heat drying (water removal) the water-based colored paint applied to the substrate surface. Therefore, it is possible to appropriately apply a photocurable clear paint on the colored layer without photocuring the colored paint (colored layer) using light such as ultraviolet rays.

Furthermore, while using a water-based colored paint containing a photocurable resin, a colored layer is formed without photocuring (irradiating light such as ultraviolet rays), and the surface of the colored layer contains the photocurable resin. After the clear paint is applied, it is photocured (irradiates light such as ultraviolet rays).
For this reason, the interlayer adhesion between the colored layer and the clear layer formed on the surface is improved, and the risk of delamination of both is extremely reduced. This is because the colored layer is not photocured in the coloring process, so there are many unreacted functional groups on the surface, and when the clear paint is irradiated with light such as ultraviolet rays, the resin on the surface of the colored layer This is probably because (molecules) and the resin (molecules) of the clear paint react and bond.

And according to the manufacturing method of this invention, a colored layer can also be photocured with a clear layer. This is considered to be due to the following reason.
The water-based colored paint contains a photoinitiator in addition to the photocurable resin. For this reason, in the clear layer forming step, when light such as ultraviolet rays or visible light is irradiated, the photocurable resin in the colored layer can be photocured by the action of the photoinitiator in the colored layer. Specifically, in the production method of the present invention, an aqueous colored paint containing 12 wt% or more of a colored solid content (colored pigment or dye) is used, so that the colored layer becomes dark or white, but the clear paint has ultraviolet rays or the like. The water-based colored paint (colored layer) can also be photocured to some extent when the light is irradiated. Therefore, cohesive failure of the colored layer can be suppressed.

  Furthermore, in the method for producing a coated product, the water-based colored paint is less than 30 wt% in the paint component obtained by removing the photoinitiator from the water-based colored paint in combination with the colored solid content and other inorganic substances. It is good that it is a manufacturing method of the painting thing containing.

  On the other hand, if the ratio of the colored solid content contained in the water-based colored paint is too large, the ratio of the photocurable water-based resin will be too small. Therefore, even if the water-colored paint (colored layer) is photocured. The film strength (cohesive force) of the colored layer is weak and there is a risk of cohesive failure. Also, as the proportion of the colored solid content in the water-based colored paint is increased, the viscosity of the water-colored water-based paint becomes too large as the proportion of the photocurable aqueous resin is increased. There is a possibility that gelation will occur with the passage of time, making it impossible to paint properly.

  On the other hand, in the production method of the present invention, in the coloring step, an aqueous colored paint containing less than 30 wt% of the colored solid content and other inorganic substances in the paint component obtained by removing the photoinitiator from the aqueous colored paint is used. Yes. Thus, in the water-based colored paint in which the ratio of the colored solid content is limited, the photo-curable water-based resin can be contained in the water-based colored paint in an appropriate ratio. Therefore, there is no possibility that the above problems occur, and the water-based colored paint can be appropriately applied. Furthermore, since a colored layer having an appropriate film strength (cohesive force) can be formed by photocuring in the clear layer forming step, cohesive failure of the colored layer can be suppressed.

Other inorganic substances include extender pigments and powders of fibrous magnesium silicate minerals.
Further, the water-based colored paint may not contain inorganic substances such as extender pigments in addition to the colored solid content. In this case, it is sufficient that the colored solid content is less than 30 wt%.

  Furthermore, in any one of the above-described methods for producing a coated product, the water-based colored paint has a weight W1 that is a combination of the colored solid content and other inorganic substances, and a weight W2 of the photocurable water-based resin of 0. It is good that it is a manufacturing method of the coated material which satisfies the relation of 12 <W2 / W1 <1.2.

  If the ratio of the photocurable aqueous resin is made too small relative to the ratio of the colored solid content in the aqueous colored paint, the film strength (cohesive strength) of the colored layer will be increased even if the aqueous colored paint (colored layer) is photocured. It is weak and has a risk of cohesive failure. On the other hand, in the production method of the present invention, in the coloring step, an aqueous colored coating material satisfying the relationship of 0.12 <W2 / W1 in which the colored solid content and other inorganic substances, the photocurable aqueous resin, and the weight ratio satisfy 0.12 <W2 / W1. Yes. Thus, when the photocurable aqueous resin is used in a clear layer forming step by using an aqueous coloring paint containing more than 0.12 times (by weight) of the colored solid content, when the photocurable resin is photocured in the clear layer forming step, A colored layer having film strength (cohesive strength) can be formed. Therefore, the risk of cohesive failure of the colored layer can be reduced.

On the other hand, if the ratio of the photocurable water-based resin is too large, the viscosity of the water-based colored paint becomes too large, and further, the storage stability is lowered and gels with the passage of time. There is a risk of disappearing. On the other hand, in the manufacturing method of the present invention, a water-based colored paint satisfying the relationship of W1 / W2 <1.2 is used. Thus, by using the water-based colored paint in which the ratio of the photocurable water-based resin is limited, there is no possibility that the above-described problems occur, and the water-based colored paint can be appropriately applied.
In addition to the colored solid content, the water-based colored paint may not contain inorganic substances such as extender. In this case, the weight of the colored solid content is W1.

  Furthermore, in any one of the above-described methods for producing a coated product, the water-based colored paint may include 0.15% by weight of the photoinitiator with respect to 100 parts by weight of the paint component obtained by removing the photoinitiator from the water-based colored paint. It is good that it is the manufacturing method of the coating material containing more than one part.

  In the coloring step, by using an aqueous coloring paint containing a photoinitiator at the above ratio, when the clear layer is photocured in the clear layer forming step, the colored layer can also be appropriately photocured.

Furthermore, it is a manufacturing method of any one of the above-described coated objects, and in the coloring step, it is preferable to be a manufacturing method of a coated object in which the water-based colored paint is applied at 2.5 g / (30 cm) ² or more.

In recent years, there has been an increasing demand for increasing the thickness of the colored layer in order to enhance the aesthetics of the paint. However, the conventional method has a problem that if the water-based colored paint is applied thick (specifically, 2.5 g / (30 cm) ² or more), the colored layer is not sufficiently cured and cohesive failure occurs. It was. On the other hand, if the irradiation amount of light such as ultraviolet rays is increased to sufficiently cure the colored layer, the surface of the colored layer is excessively photocured, resulting in delamination with the clear layer. . In particular, when the colored layer is dark or white, the above problem is serious.

On the other hand, in the production method of the present invention, as described above, a coating film can be formed without irradiating light such as ultraviolet rays while using a water-based colored paint containing a photocurable resin. A clear paint containing a photocurable resin is applied to the surface of the film, and is cured by irradiating light such as ultraviolet rays to form a clear layer. For this reason, the interlayer adhesion between the colored layer and the clear layer formed on this surface is improved, and the risk of delamination of both is extremely reduced.
Moreover, since the water-based colored paint contains a photoinitiator, when the clear paint is irradiated with light such as ultraviolet rays, the clear paint can be photocured and the colored layer can be photocured. This can reduce the risk of cohesive failure of the colored layer even when a water-based colored paint is applied in an amount of 2.5 g / (30 cm) ² or more.

  Furthermore, in any one of the above-described methods for producing a coated product, the photocurable aqueous resin contained in the water-based colored paint has an average molecular weight of 2500 or more and a minimum film-forming temperature of 0 ° C. or less. A manufacturing method is preferred.

  In the method for producing a coated product of the present invention, an aqueous colored paint containing a photocurable aqueous resin having an average molecular weight of 2500 or more and a minimum film forming temperature of 0 ° C. or less is used. For this reason, it is possible to form a colored layer in which a coating film is suitably formed in a tack-free state simply by applying a water-based colored paint to the substrate surface and then drying (removing water). Therefore, a photocurable clear paint can be suitably applied on the colored layer without photocuring the colored paint (colored layer) using ultraviolet rays.

  Applying any of the above-mentioned water-based colored paints to the surface of the substrate, removing the moisture by heat drying without photocuring, and forming a colored layer; and a photocurable resin on the surface of the colored layer And a clear layer forming step of forming a clear layer by applying a clear paint containing a clear layer and curing it together with the colored layer.

  In the method for producing a coated product of the present invention, in the coloring step, an aqueous colored paint containing 12 wt% or more of a colored solid content (colored pigment or dye) is applied to a paint component obtained by removing the photoinitiator from the aqueous colored paint. If a colored layer is formed using a colored paint containing a colored solid content at such a ratio, the colored layer can be appropriately dark or white. In particular, white (including a color approximating white) is difficult to develop, but if a colored layer is formed using a colored paint containing a colored solid content at the above ratio, the colored layer is appropriately white (approximate to white). Color).

  Furthermore, this water-based colored paint contains a photocurable aqueous resin having a minimum film-forming temperature of 100 ° C. or lower. For this reason, a coating film can be formed only by heat drying (moisture removal) without irradiating light such as ultraviolet rays (photocuring). Furthermore, since the average molecular weight of the photocurable water-based resin is 1000 or more, a tack-free colored layer can be formed simply by heat drying (water removal) the water-based colored paint applied to the substrate surface. Therefore, it is possible to appropriately apply a photocurable clear paint on the colored layer without photocuring the colored paint (colored layer) using light such as ultraviolet rays.

Furthermore, while using a water-based colored paint containing a photocurable resin, a colored layer is formed without photocuring (irradiating light such as ultraviolet rays), and the surface of the colored layer contains the photocurable resin. After the clear paint is applied, it is photocured (irradiates light such as ultraviolet rays).
For this reason, the interlayer adhesion between the colored layer and the clear layer formed on the surface is improved, and the risk of delamination of both is extremely reduced. This is because the colored layer is not photocured in the coloring process, so there are many unreacted functional groups on the surface, and when the clear paint is irradiated with light such as ultraviolet rays, the resin on the surface of the colored layer This is probably because (molecules) and the resin (molecules) of the clear paint react and bond.

And according to the manufacturing method of this invention, a colored layer can also be photocured with a clear layer. This is considered to be due to the following reason.
The water-based colored paint contains a photoinitiator in addition to the photocurable resin. For this reason, in a clear layer formation process, when light, such as an ultraviolet-ray and visible light, is irradiated, it becomes possible to cleave the photoinitiator in a colored layer and to photocure the photocurable resin in a colored layer. Specifically, in the production method of the present invention, an aqueous colored paint containing 12 wt% or more of a colored solid content (colored pigment or dye) is used, so that the colored layer becomes dark or white, but the clear paint has ultraviolet rays or the like. The water-based colored paint (colored layer) can also be photocured to some extent when the light is irradiated. Therefore, cohesive failure of the colored layer can be suppressed.

(Examples and Comparative Examples)
Examples of the present invention and comparative examples will be described below.

Example 1
Sample D (samples D1-D5) was manufactured as a coated product of the present invention.
The method for producing the water-based colored paint of the present invention used for sample D1 will be described with reference to FIG. First, 8.0 parts by weight of the aqueous resin composition is stirred and mixed with 64.0 parts by weight of water. Thereafter, 3.2 parts by weight of a preservative, an antifoaming agent, a leveling agent, and an antifreezing agent are added as an auxiliary agent with stirring. In all of the examples (Examples 1 to 3) of the present invention, the product name LR8983 (average molecular weight 10,000, MFT 0 ° C., urethane acrylate) manufactured by BASF Corporation is used as the aqueous resin composition.

  Next, 2.4 parts by weight of an associative thickener having thixotropic properties was added with stirring. In Examples (Examples 1 to 3) of the present invention, Primal RM-12W (Rohm & Haas, trade name) is used as an associative thickener having thixotropic properties. Next, 2.4 parts by weight of an associative thickener having a Newtonian viscosity was added with stirring. In all of the examples (Examples 1 to 3) of the present invention, Rheorate 350 (trade name, manufactured by Rheox) is used as an associative thickener having a Newtonian viscosity.

Next, 20.0 parts by weight of a water-dispersed colorant was added with stirring to obtain an aqueous colored paint used for Sample D1. In all of the examples (Examples 1 to 3) of the present invention, colored processed pigments manufactured by Dainichi Seika Co., Ltd. and trade name AF color white are used as the water dispersion colorant.
The water-based colored paints for Samples D2 to D5 are 0.15 parts by weight, 0.3 parts by weight, 0.6 parts by weight and 1.2 parts by weight of photoinitiator 1 with respect to the water-based colored paint for Samples D1, respectively. A part by weight is added. Photoinitiator 1 is Darocur 4265 (manufactured by Ciba Specialty Chemicals, trade name, visible light cleavage type).

  Here, the component content rate of the water-colored coating material for sample D (samples D1-D5) manufactured as mentioned above is shown in the upper part of FIG. The water-based colored paint for sample D1 is 3.6 wt% of a photocurable aqueous resin (urethane acrylate), 5.0 wt% of a colored solid content (colored pigment content), and other solid content (auxiliary, thickener 1). , 2 etc.) and 4.6% by weight of volatile matter (mainly water). The water-based colored paints for samples D2 to D5 contain 0.15 wt%, 0.30 wt%, 0.60 wt%, and 1.20 wt% of photoinitiator 1 in addition to the components of sample D1, respectively.

Next, the manufacturing method of the sample D (samples D1-D5) which is the coating material of the present Example 1 is demonstrated.
First, in the coloring step, a colored layer was formed on the surface of the wooden substrate using the water-based colored paint produced as described above. Specifically, 3.0 g / (30 cm) ² of an aqueous colored coating was applied to the surface of the wooden substrate in the order of sponge application, reverse oyster and natural rubber roll application. Next, using a heater, the applied water-based colored paint was dried with hot air (80 ° C. × 1 minute) (water removal) to form a colored layer.

  By the way, in the present Example 1, the filling coating in the recessed part (for example, the conduit | pipe part of a wooden base material, etc.) of the surface of a wooden base material was favorable. This is presumably because a thickener having thixotropic properties, specifically, Primal RM-12W (Rohm & Haas, trade name) was added as a component of the aqueous coloring paint. Furthermore, the transfer coating onto the flat part of the surface of the woody substrate was also good. This is considered to be because a thickener having a Newtonian viscosity, specifically, Leorate 350 (trade name, manufactured by Rheox) was added as a component of the water-based colored paint of the present invention.

Next, in the clear layer forming step, a clear layer was formed on the surface of the colored layer. Specifically, first, using a roll coater, as a primer, a clear paint containing a photocurable resin (specifically, IST200 (manufactured by NATCO, trade name)) is 2.0 g / (30 cm). ² applied. Thereafter, using a UV lamp, light (peak wavelength: 360 to 370 nm) was irradiated onto the clear coating and photocured to form a clear layer. Further, as an intermediate coating, a clear paint containing a photocurable resin (specifically, IST400 (trade name, manufactured by NATCO CORPORATION)) of 2.0 g / (30 cm) ^{2 is} applied, and light is applied in the same manner as the undercoat. Cured. Furthermore, as an overcoat, a clear paint containing a photocurable resin (specifically, IST500 (manufactured by NATCO, trade name)) is applied at 2.0 g / (30 cm) ² and photocured in the same manner as the undercoat. I let you. In this way, a clear layer composed of three layers was formed.
As described above, five types of coated objects (samples D1 to D5) according to Example 1 were obtained.

  By the way, in the present Example 1, the applied water-based colored paint is suitably cured by simply drying with hot air (moisture removal) (80 ° C. × 1 minute) without photocuring (irradiating light such as ultraviolet rays). Could be formed. This is because the minimum film-forming temperature of the photocurable aqueous resin (urethane acrylate) contained in the aqueous resin composition (LR8983) added when producing the aqueous colored paint is 0 ° C. This is considered to be because the coating film can be sufficiently formed if it can be removed moderately.

  Furthermore, the surface of the colored layer could be suitably brought into a tack-free state simply by hot air drying (water removal) (80 ° C. × 1 minute). This is considered because the average molecular weight of the photocurable aqueous resin (urethane acrylate) contained in the aqueous resin composition (LR8983) is 10,000. For this reason, the clear paint is appropriately applied on the colored layer in the clear layer forming step without irradiating light such as ultraviolet rays (light that cleaves the photoinitiator 1) and photocuring the aqueous colored paint (colored layer). Could be applied.

(Comparative Example 1)
Sample A (samples A1 to A14) was manufactured as a coated product of Comparative Example 1.
First, the water-based colored paint used for sample A1 was produced in the same manner as the water-colored paint of Example 1 (sample D). Specifically, as shown in FIG. 1, 73.9 parts by weight of water, 9.0 parts by weight of an aqueous resin composition, and 3.7 auxiliaries (preservatives, antifoaming agents, leveling agents, antifreezing agents) were added. Part by weight, 2.8 parts by weight of an associative thickener having thixotropic properties, 2.8 parts by weight of an associative thickener having a Newtonian viscosity, and 7.8 parts by weight of a water-dispersed colorant are stirred and mixed. Manufactured.

  In addition, also in this comparative example 1 (samples A1-A14), as in Example 1, as the aqueous resin composition, a product name LR8983 (average molecular weight 10,000, MFT 0 ° C., urethane acrylate) manufactured by BASF Corporation is used. . Further, as an associative thickener having thixotropic properties, Primal RM-12W (trade name, manufactured by Rohm & Haas) is used. In addition, as an associative thickener having a Newtonian viscosity, Rheorate 350 (trade name, manufactured by Rheox) is used. Furthermore, as a water-dispersed colorant, a colored processed pigment manufactured by Dainichi Seika Co., Ltd., trade name AF color white is used.

Next, water-based colored paints for samples A2 to A14 were produced. Specifically, the water-based colored paint for samples A2 to A5 is 0.15 parts by weight, 0.30 parts by weight, respectively, of photoinitiator 1 (Darocur 4265) with respect to the water-based colored paint for sample A1. It was obtained by adding 0.60 parts by weight and 1.20 parts by weight. Moreover, the water-based colored paints for Samples A6 to A9 are 0.15 parts by weight, 0.30 parts by weight, 0.60 parts by weight, 1 part by weight of the photoinitiator 2 with respect to the water-based colored paint for Samples A1, respectively. Obtained by adding 20 parts by weight. Further, the water-based colored paints for Samples A10 to A14 are 0.15 parts by weight, 0.30 parts by weight, 0.60 parts by weight, 1 part by weight of the photoinitiator 3 with respect to the water-based colored paint for Samples A1, respectively. 20 parts by weight and 3.00 parts by weight were obtained.
The photoinitiator 2 is Lucillin TPO-L (manufactured by BASF, trade name, visible light cleavage type). The photoinitiator 3 is Irgacure 184 (trade name, ultraviolet cleavage type, manufactured by Ciba Specialty Chemicals) or Darocur 1173 (trade name, ultraviolet cleavage type, manufactured by Ciba Specialty Chemicals).

Next, in the same manner as in Example 1, each of the above 14 types (samples A1 to A14) of water-based colored paints was applied to the surface of the wooden substrate at 3.0 g / (30 cm) ^{2 and} dried with hot air (80 ° C. X 1 minute) (water removal) to form a colored layer. In addition, also in this comparative example 1, like Example 1, the filling coating in the recessed part (for example, the conduit | pipe part of a wooden base material etc.) of the surface of a wooden base material was favorable.
Thereafter, in the same manner as in Example 1, a three-layer clear layer (undercoat, intermediate coat, and topcoat) was formed on the surface of the colored layer. In this comparative example 1, the same clear paint as in Example 1 is used. As described above, 14 types of coated objects (samples A1 to A14) according to Comparative Example 1 were obtained.

(Comparative Example 2)
Sample B was produced as a coated product of Comparative Example 2.
First, the water-based colored paint used for Sample B was produced in the same manner as the water-based colored paint of Example 1 (Sample D). Specifically, as shown in FIG. 1, 70.05 parts by weight of water, 8.75 parts by weight of an aqueous resin composition, and auxiliary agents (preservatives, antifoaming agents, leveling agents, antifreezing agents) are added at 3.50. Part by weight, 2.60 parts by weight of an associative thickener having thixotropic properties, 2.60 parts by weight of an associative thickener having a Newtonian viscosity, and 12.5 parts by weight of a water-dispersed colorant are stirred and mixed. Manufactured.

  In addition, also in this comparative example 2 (sample B), the product name LR8983 (average molecular weight 10,000, MFT0 degreeC, urethane acrylate) by BASF Corporation is used as an aqueous resin composition similarly to Example 1. Further, as an associative thickener having thixotropic properties, Primal RM-12W (trade name, manufactured by Rohm & Haas) is used. In addition, as an associative thickener having a Newtonian viscosity, Rheorate 350 (trade name, manufactured by Rheox) is used. Furthermore, as a water-dispersed colorant, a colored processed pigment manufactured by Dainichi Seika Co., Ltd., trade name AF color white is used.

Next, 3.0 g / (30 cm) ^{2 of} the above water-based colored paint was applied to the surface of the wooden substrate in the same manner as in Example 1 and dried with hot air (80 ° C. × 1 minute) (removal of water). ), A colored layer was formed. In addition, also in the present comparative example 2, as in the case of Example 1, the filling coating into the concave portion (for example, the conduit portion of the wooden base material) on the surface of the wooden base material was good.
Thereafter, in the same manner as in Example 1, a three-layer clear layer (undercoat, intermediate coat, and topcoat) was formed on the surface of the colored layer. In this comparative example 2, the same clear paint as that in Example 1 is used. As described above, a coated product (Sample B) according to Comparative Example 2 was obtained.

(Comparative Example 3)
Sample C was produced as a coated product of Comparative Example 3.
First, the water-based colored paint used for Sample C was manufactured in the same manner as the water-colored paint of Example 1 (Sample D). Specifically, as shown in FIG. 1, 67.5 parts by weight of water, 8.5 parts by weight of an aqueous resin composition, and auxiliary agents (preservatives, antifoaming agents, leveling agents, antifreezing agents) are added to 3.4. Part by weight, 2.5 parts by weight of an associative thickener having thixotropic properties, 2.5 parts by weight of an associative thickener having a Newtonian viscosity, and 15.6 parts by weight of a water-dispersed colorant are mixed with stirring. Manufactured.

  In Comparative Example 3 (Sample C), as in Example 1, as the aqueous resin composition, trade name LR8983 (average molecular weight 10,000, MFT 0 ° C., urethane acrylate) manufactured by BASF Corporation is used. Further, as an associative thickener having thixotropic properties, Primal RM-12W (trade name, manufactured by Rohm & Haas) is used. In addition, as an associative thickener having a Newtonian viscosity, Rheorate 350 (trade name, manufactured by Rheox) is used. Furthermore, as a water-dispersed colorant, a colored processed pigment manufactured by Dainichi Seika Co., Ltd., trade name AF color white is used.

Next, 3.0 g / (30 cm) ^{2 of} the above water-based colored paint was applied to the surface of the wooden substrate in the same manner as in Example 1 and dried with hot air (80 ° C. × 1 minute) (removal of water). ), A colored layer was formed. In addition, also in this comparative example 3, like Example 1, the filling coating in the recessed part (For example, the conduit | pipe part of a wooden base material, etc.) of the surface of a wooden base material was favorable.
Thereafter, in the same manner as in Example 1, a three-layer clear layer (undercoat, intermediate coat, and topcoat) was formed on the surface of the colored layer. In this comparative example 3, the same clear paint as in Example 1 is used. As described above, a coated product (Sample B) according to Comparative Example 3 was obtained.

  When samples A to D manufactured as described above were examined for the degree of coloring of the painted surface, sample D (samples D1 to D5) developed a clear white color. On the other hand, in all of samples A to C, coloring was thin and the painted surface could not be made clear white. This is considered to be due to the difference in the proportion of the colored solid content (specifically, the colored pigment content) contained in the aqueous colored paint. That is, as shown in FIG. 2, in the water-based colored paints for Samples A to C, the color pigment content contained in the paint component excluding the photoinitiator from the water-colored paint is 5.0 wt% and 8.0 wt%. The reason is considered to be as large as 12.8 wt% in Sample D, whereas it is as small as 10.0 wt%. From this result, it can be said that the painted surface can be made clear white by using the aqueous colored paint containing 12 wt% or more of the colored solid content in the paint component obtained by removing the photoinitiator from the aqueous colored paint.

  Next, the coating film peeling strength was measured by the 45 degree | times peeling method about the coating material of sample AD according to JISK-5400 using the film peeling tester. Specifically, first, the coated films (clear layer and colored layer) of the samples A to D are cut to create 100 squares of 2 mm square (hereinafter also referred to as “coating grids”). Next, using a film peeling tester, a cellophane tape was stuck on the grid of the coating film, and the cellophane tape was pulled up at an angle of 45 degrees. At this time, the number of peeling of the coating grid was investigated. The results are shown in the lower part of FIG.

As shown in the lower part of FIG. 2, in Samples A (A1 to A14), B, and C, there was no peeling of the coating grid. That is, cohesive failure of the colored layer did not occur, and delamination between the colored layer and the clear layer did not occur.
On the other hand, in sample D, there was a sample in which the paint film was peeled off. Specifically, in Samples D1 and D2, ten or more coating grids out of 100 coating grids were peeled off. In sample D3, 6-9 coating grids were peeled off. However, in Samples D4 and 5, there was no peeling of the coating grid. In addition, all peeling of the coating grid of samples D1-D3 was peeling by the cohesive failure of a colored layer.

Here, the above test results are examined.
First, four samples (A1, B, C, D1) using a water-based colored paint that does not contain a photoinitiator will be compared. In Samples A1, B, and C, none of the coating grids were peeled off, whereas in Sample D1, 10 or more coating grids were peeled off. This is considered to be due to the difference in the ratio of the colored solid content (colored pigment content) contained in the aqueous colored paint. That is, it is considered that the coating strength (cohesive force) of the colored layer is weak in the sample D1 because the colored pigment content is larger than in the samples A1, B, and C. For this reason, it is thought that the cohesive failure of the colored layer has occurred.

However, cohesive failure of the colored layer did not occur in Samples D4 and 5 using an aqueous colored paint containing a colored solid content (colored pigment content) equivalent to Samples D1 to D3. This is because, when a predetermined amount of photoinitiator is contained in the water-based colored paint (colored layer), when the light is irradiated in the clear layer forming step, the colored layer is appropriately photocured together with the clear layer. It is thought that it was possible. Thereby, it is thought that the coating film strength (cohesion force) of the colored layer could be increased.
From the above results, when a colored layer is formed using an aqueous colored paint containing 12 wt% or more of a colored solid in the paint component obtained by removing the photoinitiator from the aqueous colored paint, a predetermined amount is added to the aqueous colored paint. It can be said that the cohesive failure of the colored layer can be suppressed by containing the photoinitiator.

(Example 2)
Next, sample E (E1 to E14), sample F (F1 to F14), sample G (G1 to G14), sample H (H1 to H5), sample I, and sample J are applied as the coated objects according to Example 2. Manufactured.

  First, the water-based colored paint used for sample E1 was produced by the same method as the water-based colored paint of Example 1 (sample D). Specifically, as shown in FIG. 3, 65.0 parts by weight of water, 4.5 parts by weight of an aqueous resin composition, and 3.8 auxiliaries (preservatives, antifoaming agents, leveling agents, antifreeze agents) are added. 1 part by weight, 1.35 parts by weight of an associative thickener having thixotropic properties, 1.35 parts by weight of an associative thickener having a Newtonian viscosity, and 24.0 parts by weight of a water-dispersed colorant are stirred and mixed. Manufactured.

  In Example 2 (samples E to J), as in Example 1, as the aqueous resin composition, product name LR8983 (average molecular weight 10,000, MFT 0 ° C., urethane acrylate) manufactured by BASF Corporation is used. . Further, as an associative thickener having thixotropic properties, Primal RM-12W (trade name, manufactured by Rohm & Haas) is used. In addition, as an associative thickener having a Newtonian viscosity, Rheorate 350 (trade name, manufactured by Rheox) is used. Furthermore, as a water-dispersed colorant, a colored processed pigment manufactured by Dainichi Seika Co., Ltd., trade name AF color white is used.

  Next, water-based colored paints for samples E2 to E14 were produced. Specifically, the water-based colored paints for samples E2 to E5 are 0.15 parts by weight, 0.30 parts by weight, respectively, of photoinitiator 1 (Darocur 4265) with respect to the water-based colored paint for sample E1. It was obtained by adding 0.60 parts by weight and 1.20 parts by weight. In addition, the water-based colored paints for Samples E6 to E9 were 0.15 parts by weight, 0.30 parts by weight, 0.60 parts by weight, Obtained by adding 20 parts by weight. Moreover, the water-based colored paints for Samples E10 to E14 are 0.15 parts by weight, 0.30 parts by weight, 0.60 parts by weight, 1 part by weight of the photoinitiator 3 with respect to the water-based colored paint for Sample E1, respectively. 20 parts by weight and 3.00 parts by weight were obtained.

  Furthermore, the water-based colored paint used for Sample F1 was produced in the same manner as the water-based colored paint of Example 1 (Sample D). Specifically, as shown in FIG. 3, 62.49 parts by weight of water, 5.75 parts by weight of an aqueous resin composition, and 4.3 auxiliaries (preservatives, antifoaming agents, leveling agents, antifreeze agents) were added. 1 part by weight, 1.73 parts by weight of an associative thickener having thixotropic properties, 1.73 parts by weight of an associative thickener having a Newtonian viscosity, and 24.0 parts by weight of a water-dispersed colorant are stirred and mixed. Manufactured.

  Subsequently, the water-colored coating material for samples F2-F14 was manufactured. Specifically, the water-based colored paint for samples F2 to F5 is 0.15 parts by weight, 0.30 parts by weight, respectively, of photoinitiator 1 (Darocur 4265) with respect to the water-based colored paint for sample F1. It was obtained by adding 0.60 parts by weight and 1.20 parts by weight. In addition, the water-based colored paints for Samples F6 to F9 were 0.15 parts by weight, 0.30 parts by weight, 0.60 parts by weight, Obtained by adding 20 parts by weight. In addition, the water-based colored paints for Samples F10 to F14 are 0.15 parts by weight, 0.30 parts by weight, 0.60 parts by weight, 1 part by weight of the photoinitiator 3 with respect to the water-based colored paint for Samples F1, respectively. 20 parts by weight and 3.00 parts by weight were obtained.

  Furthermore, the water-based colored paint used for Sample G1 was produced in the same manner as the water-colored paint of Example 1 (Sample D). Specifically, as shown in FIG. 3, 60.0 parts by weight of water, 7.0 parts by weight of an aqueous resin composition, and 4.8 auxiliaries (preservatives, antifoaming agents, leveling agents, antifreezing agents) were added. Part by weight, 2.1 parts by weight of an associative thickener having thixotropic properties, 2.1 parts by weight of an associative thickener having a Newtonian viscosity, and 24.0 parts by weight of a water-dispersed colorant are mixed with stirring. Manufactured.

  Next, water-based colored paints for samples G2 to G14 were manufactured. Specifically, the water-based colored paints for Samples G2 to G5 are 0.15 parts by weight, 0.30 parts by weight, respectively, of Photoinitiator 1 (Darocur 4265) with respect to the water-colored paint for Samples G1. It was obtained by adding 0.60 parts by weight and 1.20 parts by weight. Moreover, the water-based colored paints for Samples G6 to G9 are 0.15 parts by weight, 0.30 parts by weight, 0.60 parts by weight, Obtained by adding 20 parts by weight. In addition, the water-based colored paints for Samples G10 to G14 are 0.15 parts by weight, 0.30 parts by weight, 0.60 parts by weight, 20 parts by weight and 3.00 parts by weight were obtained.

Furthermore, the water-based colored paint used for Sample H1 was produced in the same manner as the water-colored paint of Example 1 (Sample D). Specifically, as shown in FIG. 3, 29.0 parts by weight of water, 37.5 parts by weight of an aqueous resin composition, 5.0 auxiliaries (preservatives, antifoaming agents, leveling agents, antifreezing agents) are added. Part by weight, 2.25 parts by weight of an associative thickener having thixotropic properties, 2.25 parts by weight of an associative thickener having a Newtonian viscosity, and 24.0 parts by weight of a water-dispersed colorant are mixed with stirring. Manufactured.
Subsequently, the water-colored coating material for samples H2-H5 was manufactured. Specifically, 0.15 parts by weight, 0.30 parts by weight, 0.60 parts by weight, and 1.20 parts by weight of photoinitiator 1 (Darocur 4265) are respectively added to the water-based colored paint for sample H1. Obtained by addition.

  Furthermore, the water-based colored paint used for Sample I was produced in the same manner as the water-colored paint of Example 1 (Sample D). Specifically, as shown in FIG. 3, 21.5 parts by weight of water, 45.0 parts by weight of an aqueous resin composition, and 5.0 auxiliaries (preservatives, antifoaming agents, leveling agents, antifreezing agents) are added. Part by weight, 2.25 parts by weight of an associative thickener having thixotropic properties, 2.25 parts by weight of an associative thickener having a Newtonian viscosity, and 24.0 parts by weight of a water-dispersed colorant are mixed with stirring. Manufactured.

  Furthermore, the water-based colored paint used for Sample J was produced in the same manner as the water-based colored paint of Example 1 (Sample D). Specifically, as shown in FIG. 3, 6.5 parts by weight of water, 60.0 parts by weight of an aqueous resin composition, 5.0 auxiliaries (preservatives, antifoaming agents, leveling agents, antifreezing agents) Part by weight, 2.25 parts by weight of an associative thickener having thixotropic properties, 2.25 parts by weight of an associative thickener having a Newtonian viscosity, and 24.0 parts by weight of a water-dispersed colorant are mixed with stirring. Manufactured.

Next, a storage stability test was carried out on the 49 types of aqueous coloring paints (samples E1 to E14, F1 to F14, G1 to G14, H1 to H5, I and J).
Specifically, 49 types of water-based colored paints were each left in a thermostatic chamber at 50 ° C. for 1 week. As a result, as shown in FIG. 4, 47 types (samples E1 to E14, F1 to F14, G1 to G14, and H1 to H5) of the water-based colored paints have particularly good storage stability without any change. there were.

On the other hand, gelation has progressed in the water-based colored paints for Samples I and J. For this reason, the water-based colored paints for Samples I and J could not be applied to the surface of the wooden substrate. This is considered due to the following reasons.
As shown in FIG. 4, each of the water-based colored paints for Samples E to J contains a colored solid content (colored pigment content) at the same ratio (specifically, 15 wt%). However, the ratio of the photocurable aqueous resin (solid content) is different, and the content rate is higher in the order of samples E, F, G, H, I, and J. That is, the content of the photocurable aqueous resin (solid content) is higher in the water-based colored paints for Samples I and J than in other sample paints. For this reason, it is thought that storage stability fell and gelatinization has progressed.

  From the above results, in order to improve storage stability in an aqueous colored paint containing a large amount (specifically, 12 wt% or more) of colored solids (colored pigments), colored solids (colored pigments) It can be said that it is necessary to suppress the ratio of the weight W2 of the photocurable aqueous resin (solid content) to the weight W1. Specifically, the water-based colored paints for samples I and J that have undergone gelation contain 15 wt% of colored solid content (colored pigment content) and 18 wt% or more of a photocurable aqueous resin (solid content). Therefore, it is considered that good storage stability cannot be obtained when W2 / W1 ≧ 1.2 (= 18/15). In other words, it is considered that the storage stability of the water-based colored paint can be improved by satisfying the relationship of W2 / W1 <1.2 (= 18/15).

Next, 47 types of water-colored paints (samples E1 to E14, F1 to F14, G1 to G14, and H1 to H5), which had good storage stability, were formed in the same manner as in Example 1, respectively. The surface was coated with 3.0 g / (30 cm) ^{2 and} dried with hot air (80 ° C. × 1 minute) (water removal) to form a colored layer. In addition, the 47 types of water-based colored paints, as in Example 1, were satisfactorily filled in the recesses on the surface of the wooden substrate (for example, the conduit portion of the wooden substrate). In addition, the applied water-based colored paint is suitably formed with a coating film by simply drying with hot air (removing moisture) (80 ° C. × 1 minute) without irradiating light such as ultraviolet rays (light that cleaves the photoinitiator). In addition, the surface of the colored layer could be brought into a tack-free state.

  Thereafter, in the same manner as in Example 1, a three-layer clear layer (undercoat, intermediate coat, and topcoat) was formed on the surface of the colored layer. As described above, 47 kinds of coated objects (samples E1 to E14, F1 to F14, G1 to G14, and H1 to H5) according to Example 2 were obtained. In the second embodiment, the same clear paint as in the first embodiment is used.

  For the 47 types of coated products (samples E1 to E14, F1 to F14, G1 to G14, H1 to H5) manufactured as described above, the degree of coloring of the painted surface was investigated. A white color was developed. This is presumably because an aqueous colored paint containing 12 wt% or more (specifically, 15 wt%) of a colored solid content in the paint component obtained by removing the photoinitiator from the aqueous colored paint.

  Next, in the same manner as in Example 1, a peeling test of the coating grid was performed on the 47 kinds of coated products (samples E1 to E14, F1 to F14, G1 to G14, and H1 to H5). The results are shown in the lower part of FIG.

In Samples F to H (F1 to F14, G1 to G14, H1 to H5), it can be seen that peeling of the coating grids can be suppressed as the ratio of the initiator contained in the aqueous coloring paint is increased. Specifically, cohesive failure of the colored layer could be suppressed by using an aqueous colored paint containing a predetermined amount or more of an initiator.
On the other hand, in sample E (samples E1-E14), even if the ratio of the initiator contained in the water-based colored paint was increased, it was not possible to suppress peeling of the coating grid. Specifically, even if the ratio of the initiator contained in the water-based colored paint was increased, the cohesive failure of the colored layer could not be suppressed.

This is considered due to the following reasons.
As shown in FIG. 4, each of the water-based colored paints for Samples E to J contains a colored solid content (colored pigment content) at the same ratio (specifically, 15 wt%). However, the ratio of the photocurable aqueous resin (solid content) is different, and the content of the photocurable aqueous resin (solid content) decreases in the order of samples J, I, H, G, F, and E. . That is, in the water-based colored paint for sample E, the proportion of the photocurable aqueous resin (solid content) is smaller than that of the other samples. For this reason, in the clear layer formation step, even if the colored layer can be photocured with the undercoat clear paint, the coating strength (cohesive strength) of the colored layer cannot be sufficiently increased, and cohesive failure has occurred. Conceivable.

  From the above results, when a colored layer is formed as a base of a clear layer using an aqueous colored paint containing a large amount (specifically, 12 wt% or more) of a colored solid content (colored pigment content), the colored layer is aggregated. In order to suppress destruction, it can be said that the ratio of the weight W2 of the photocurable aqueous resin (solid content) to the weight W1 of the colored solid content (colored pigment content) needs to be larger than a predetermined ratio. Specifically, in the water-based colored paint for Sample E that could not suppress cohesive failure even when a photoinitiator was added, the colored solid content (colored pigment content) was 15 wt%, and the photocurable aqueous resin (solid content). Therefore, if W2 / W1 ≦ 0.12 (= 1.8 / 15), it is considered that the cohesive failure of the colored layer may occur. Therefore, it is considered that the cohesive failure of the colored layer can be suppressed by satisfying the relationship of W2 / W1> 0.12 (= 1.8 / 15).

Next, from the results of the peeling test on samples F to H (F2 to F14, G2 to G14, H2 to H5), photoinitiator 1 (Darocur 4265), photoinitiator 2 (Lucillin TPO-L), and light The effectiveness of initiator 3 (Irgacure 184 or Darocur 1173) will be compared.
First, the effectiveness of the photoinitiators 1 to 3 is examined in the sample F (F2 to F14). As shown in FIG. 4, from the results of the samples (F10 to F14) using the water-colored paint containing the photoinitiator 3 (Irgacure 184 or Darocur 1173), the photoinitiator 3 was added in an amount of 1.20 wt% or more. Otherwise, cohesive failure of the colored layer cannot be suppressed.

  On the other hand, as can be seen from the results of the samples (F2 to F5) using the aqueous coloring paint containing the photoinitiator 1 (Darocur 4265), when the photoinitiator 1 is added at 0.60 wt%, Cohesive failure can be suppressed. Further, as can be seen from the results of the samples (F6 to F9) using the aqueous coloring paint containing the photoinitiator 2 (Lucirin TPO-L), the photoinitiator 2 can be added by adding 0.30 wt%. It is possible to suppress cohesive failure.

  Thus, the effect which suppresses cohesive failure changes with kinds of the photoinitiator contained in a water-based coloring paint. Specifically, compared with the case where the photoinitiator 3 (Irgacure 184 or Darocur 1173) which is an ultraviolet cleavage type is added, the photoinitiator 1 (Darocur 4265) or the photoinitiator 2 (which is a visible light cleavage type) ( The effect of suppressing cohesive failure is enhanced by adding Lucillin TPO-L). This is considered due to the following reasons.

  In Example 2, as in Example 1, in order to photocur the undercoat clear layer, an ultraviolet lamp that emits ultraviolet light having a long wavelength (wavelength close to visible light) (peak wavelength is 360 to 370 nm) is used. Irradiating light. The light emitted from the ultraviolet lamp includes light of various wavelengths within a predetermined range, and also includes visible light. Since visible light has a long wavelength, even when a large amount (15.0 wt%) of colored solids (colored pigments) is contained as in Example 2, the coating film (colored layer) of the aqueous colored paint is used. Easy to reach inside. Therefore, in the samples F2 to F9 to which the photoinitiator 1 or the photoinitiator 2 which is a visible light cleavage type is added, the inside of the colored layer is compared with the samples F10 to F14 to which the photoinitiator 3 which is an ultraviolet cleavage type is added. It is considered that the colored layer could be photocured more effectively.

  Similarly, for samples G (G2 to G14), the photoinitiator 3 that is an ultraviolet cleavage type is added to the samples G2 to G9 to which the photoinitiator 1 or photoinitiator 2 that is a visible light cleavage type is added. The colored layer could be photocured more effectively than the samples G10 to G14. Among these, in Sample G6, an aqueous colored paint containing only 0.15 parts by weight of photoinitiator 2 is used for 100 parts by weight of the paint component obtained by removing photoinitiator 2 from the aqueous colored paint. Cohesive failure could be suppressed. From this result, by adding 0.15 parts by weight or more of the photoinitiator to 100 parts by weight of the paint component obtained by removing the photoinitiator from the water-based colored paint, the water-based colored paint (colored layer) can be appropriately treated with light. It can be cured, and it can be said that the cohesive failure of the colored layer can be suppressed.

Next, the results of samples F2 to F5, samples G2 to G5, and samples H2 to H5 will be compared and examined. Samples F2 to F5, Samples G2 to G5, and Samples H2 to H5 have the same photoinitiator contained in the aqueous coloring paint, but differ in the content of the photocurable aqueous resin. Specifically, 2.3 wt% of the samples F2 to F5, 2.8 wt% of the samples G2 to G5, and 15.0 wt% of the samples H2 to H5 are included.
Therefore, when the results of the peel test are compared for these samples, the samples G2 to G5 and the samples H2 to H5 have the same results when the samples to which the photoinitiator 1 is added at an equivalent ratio are compared. . However, when the samples F2 to F5 were compared with the samples G2 to G5 and the samples H2 to H5 to which the photoinitiator 1 was added at an equivalent ratio, the coating strength of the colored layer (aggregation) Power) was inferior.

  Even if the photocurable aqueous resin can be photocured to the same extent by using the same photoinitiator, the higher the proportion of the photocurable aqueous resin contained in the colored layer, the more the coating film of the colored layer. This is considered because the strength (cohesive force) can be increased. As described above, in order to suppress cohesive failure of the colored layer, the ratio of the weight W2 of the photocurable aqueous resin (solid content) to the weight W1 of the colored solid content (colored pigment content) is set to W2 / W1> 0. .12 is preferable. Furthermore, preferably, it can be said that the cohesive failure of the colored layer can be further suppressed by setting W2 / W1> 0.18 (= 2.8 / 15.0) from the above results.

(Example 3)
Next, sample K (K1 to K5), sample L (L1 to L5), sample M (M1 to M5), sample N, sample P (P1 to P5), and sample Q were manufactured as the coated objects of the present invention. .

First, the water-based colored paint used for sample K1 was manufactured in the same manner as the water-colored paint of Example 1 (sample D). Specifically, as shown in FIG. 5, 27.7 parts by weight of water, 37.5 parts by weight of an aqueous resin composition, and auxiliary agents (preservatives, antifoaming agents, leveling agents, antifreezing agents) were added to 1.3. Parts by weight, 2.25 parts by weight of associative thickener having thixotropic properties, 2.25 parts by weight of associative thickener having Newtonian viscosity, 24.0 parts by weight of water-dispersed colorant, and extender pigment 5 0.0 parts by weight were prepared by stirring and mixing.
Subsequently, the water-colored coating material for samples K2-K5 was manufactured. Specifically, the water-based colored paints for samples K2 to K5 are 0.15 parts by weight, 0.30 parts by weight, respectively, of photoinitiator 1 (Darocur 4265) with respect to the water-colored paint for samples K1. It was obtained by adding 0.60 parts by weight and 1.20 parts by weight.

  In Example 3 (samples K to Q), as in Example 1, as the aqueous resin composition, product name LR8983 (average molecular weight 10,000, MFT 0 ° C., urethane acrylate) manufactured by BASF Corporation is used. . Further, as an associative thickener having thixotropic properties, Primal RM-12W (trade name, manufactured by Rohm & Haas) is used. In addition, as an associative thickener having a Newtonian viscosity, Rheorate 350 (trade name, manufactured by Rheox) is used. Furthermore, as a water-dispersed colorant, a colored processed pigment manufactured by Dainichi Seika Co., Ltd., trade name AF color white is used. In Example 3 (samples K to Q), ASP072 (trade name, manufactured by ENGELBARD) is used as the extender pigment.

Furthermore, the water-based colored paint used for Sample L1 was produced in the same manner as the water-colored paint of Example 1 (Sample D). Specifically, as shown in FIG. 5, 22.9 parts by weight of water, 37.5 parts by weight of an aqueous resin composition, and 1.1 auxiliaries (preservatives, antifoaming agents, leveling agents, antifreezing agents) were added. Parts by weight, 2.25 parts by weight of associative thickener having thixotropic properties, 2.25 parts by weight of associative thickener having Newtonian viscosity, 24.0 parts by weight of water-dispersed colorant, and extender pigment 10 0.0 parts by weight were prepared by stirring and mixing.
Subsequently, the water-colored coating material for samples L2-L5 was manufactured. Specifically, the water-based colored paints for samples L2 to L5 are 0.15 parts by weight, 0.30 parts by weight, respectively, of photoinitiator 1 (Darocur 4265) with respect to the water-based colored paint for sample L1. It was obtained by adding 0.60 parts by weight and 1.20 parts by weight.

Furthermore, the water-based colored paint used for sample M1 was manufactured by the same method as the water-colored paint of Example 1 (sample D). Specifically, as shown in FIG. 5, 48.7 parts by weight of water, 5.0 parts by weight of an aqueous resin composition, and 4.3 auxiliaries (preservatives, antifoaming agents, leveling agents, antifreezing agents) were added. Parts by weight, associative thickener having thixotropic properties, 1.5 parts by weight, associative thickener having a Newtonian viscosity, 1.5 parts by weight, water-dispersed colorant, 24.0 parts by weight, and extender pigment 15 0.0 parts by weight were prepared by stirring and mixing.
Next, water-based colored paints for samples M2 to M5 were manufactured. Specifically, the water-based colored paints for samples M2 to M5 are 0.15 parts by weight, 0.30 parts by weight, respectively, of photoinitiator 1 (Darocur 4265) with respect to the water-based colored paint for sample M1. It was obtained by adding 0.60 parts by weight and 1.20 parts by weight.

Furthermore, the water-based colored paint used for Sample P1 was produced in the same manner as the water-based colored paint of Example 1 (Sample D). Specifically, as shown in FIG. 5, 42.25 parts by weight of water, 8.75 parts by weight of the aqueous resin composition, 24.0 parts by weight of the water-dispersed colorant, and 25.0 parts by weight of the extender pigment are stirred. Produced by mixing.
Next, water-based colored paints for samples P2 to P5 were produced. Specifically, the water-based colored paint for samples P2 to P5 is 0.15 parts by weight, 0.30 parts by weight, respectively, of photoinitiator 1 (Darocur 4265) with respect to the water-based colored paint for sample P1. It was obtained by adding 0.60 parts by weight and 1.20 parts by weight.

Next, in the same manner as in Example 1, 20 types of water-based colored paints applied to samples K (K1 to K5), L (L1 to L5), M (M1 to M5), and P (P1 to P5), A 3.0 g / (30 cm) ² coating was applied to the surface of the wood substrate, followed by hot air drying (80 ° C. × 1 minute) (water removal) to form a colored layer. In addition, the above-mentioned 20 types of water-based colored paints, as in Example 1, were excellent in filling and painting into the recesses on the surface of the wooden substrate (for example, the conduit portion of the wooden substrate). In addition, the applied water-based colored paint is suitably formed with a coating film by simply drying with hot air (removing moisture) (80 ° C. × 1 minute) without irradiating light such as ultraviolet rays (light that cleaves the photoinitiator). In addition, the surface of the colored layer could be brought into a tack-free state.

  Thereafter, in the same manner as in Example 1, a three-layer clear layer (undercoat, intermediate coat, and topcoat) was formed on the surface of the colored layer. As described above, 20 kinds of coated objects (samples K1 to K5, L1 to L5, M1 to M5, P1 to P5) according to Example 3 were obtained. In the third embodiment, the same clear paint as in the first embodiment is used.

  About 20 kinds of coated products (samples K1 to K5, L1 to L5, M1 to M5, P1 to P5) manufactured as described above, the degree of coloring of the painted surface was investigated. A white color was developed. This is presumably because an aqueous colored paint containing 12 wt% or more (specifically, 20 to 40 wt%) of a colored solid content in the paint component obtained by removing the photoinitiator from the aqueous colored paint.

  Next, in the same manner as in Example 1, a peeling test of the coating grid was performed on the above-described 20 kinds of coated products (samples K1 to K5, L1 to L5, M1 to M5, P1 to P5). The results are shown in the lower part of FIG.

In samples K and L (samples K1 to K5 and L1 to L5), it can be seen that peeling of the coating grids can be suppressed as the proportion of the photoinitiator 1 contained in the aqueous coloring paint is increased. Specifically, by using an aqueous colored paint containing 0.30 part by weight or more of the photoinitiator 1 for 100 parts by weight of the paint component obtained by removing the photoinitiator 1 from the aqueous colored paint, the cohesive failure of the colored layer is caused. I was able to suppress it.
On the other hand, in samples M and P (samples M1 to M5 and P1 to P5), even if the ratio of the initiator 1 contained in the aqueous colored paint was increased, peeling of the coating grids could not be suppressed. Specifically, even if the ratio of the initiator 1 contained in the water-based colored paint was increased, the cohesive failure of the colored layer could not be suppressed.

  This is considered to be due to the difference in the content ratio of the colored solid content (colored pigment) and other inorganic substances (extreme pigment) contained in the aqueous colored paint. In samples K and L (samples K1 to K5 and L1 to L5), the solid content (colored pigment) and other inorganic substances (external pigments) are combined in the paint component obtained by removing the photoinitiator from the aqueous colored paint. The amount is limited to less than 30 wt% (specifically, 20.0 wt%, 25.0 wt%). On the other hand, in samples M and P (samples M1 to M5 and P1 to P5), a colored solid content (colored pigment content) and other inorganic substances (external pigments) are contained in the paint component obtained by removing the photoinitiator from the aqueous colored paint. 30.0 wt% or more (specifically, 30 wt%, 40 wt%).

  In Samples M and P, as described above, in order to contain a large amount of colored solids (colored pigments) and other inorganic substances (extreme pigments), the content of the photocurable aqueous resin (solid content) (Specifically, 2.0 wt%, 3.5 wt%). Specifically, in samples M and P, the ratio of the weight W2 of the photocurable aqueous resin (solid content) to the weight W1 of the combined color solid content (color pigment) and other inorganic substances (extreme pigment) is W2 respectively. /W1=0.07, 0.09 (<0.12). For this reason, in the clear layer forming step, even if the colored layer is photocured together with the undercoat clear layer, the coating strength (cohesive force) of the colored layer could not be increased to the extent that cohesive failure can be suppressed. Conceivable.

  Accordingly, an aqueous colored paint containing 30.0 wt% or more of the colored solid content (colored pigment) and other inorganic substances (extreme pigment) in the paint component obtained by removing the photoinitiator from the aqueous colored paint, W2 / W1> Water-based colored paints for Samples N and Q satisfying 0.12 were produced. Examine whether it is possible to increase the coating strength (cohesive strength) of the colored layer to such an extent that cohesive failure can be suppressed by forming the colored layer using the water-based colored paint for Samples N and Q. It was to be.

  First, an aqueous colored paint for Sample N was produced in the same manner as the aqueous colored paint of Example 1 (Sample D). Specifically, as shown in FIG. 5, 32.0 parts by weight of water, 25.0 parts by weight of an aqueous resin composition, 1.0 auxiliaries (preservatives, antifoaming agents, leveling agents, antifreezing agents) are added. Parts by weight, associative thickener having thixotropic properties, 1.5 parts by weight, associative thickener having a Newtonian viscosity, 1.5 parts by weight, water-dispersed colorant, 24.0 parts by weight, and extender pigment 15 0.0 parts by weight were prepared by stirring and mixing.

  Furthermore, the water-based colored paint used for Sample Q was produced in the same manner as the water-based colored paint of Example 1 (Sample D). Specifically, as shown in FIG. 5, 2.8 parts by weight of water, 45.0 parts by weight of an aqueous resin composition, and 0.8% of auxiliary agents (preservatives, antifoaming agents, leveling agents, antifreezing agents) are added. Parts by weight, 1.2 parts by weight of an associative thickener having thixotropic properties, 1.2 parts by weight of an associative thickener having a Newtonian viscosity, 24.0 parts by weight of an aqueous dispersion colorant, and extender pigment 25 0.0 parts by weight were prepared by stirring and mixing.

  Next, the aqueous colored paint for Samples N and Q was applied to the surface of the wooden substrate in the same manner as in Example 1, but could not be applied properly. Specifically, when the water-based colored paint applied with the sponge is reverse kidnapped, the water-colored colored paint adheres to the oyster trilol. This is because in the water-based colored paint for Samples N and Q, 30 wt% or more of the colored solid content (colored pigment) and other inorganic substances (extreme pigment) in the paint component obtained by removing the photoinitiator from the water-based colored paint. It is considered that the viscosity of the water-based colored paint is too high because the photocurable aqueous resin (solid content) is contained in a large amount as compared with the samples M and P.

Based on the above results, the water-colored paint containing 30 wt% or more of the colored solid content and other inorganic substances in the paint component obtained by removing the photoinitiator from the water-colored paint contains the photocurable aqueous resin (solid content). Even if the rate is adjusted, the water-based colored paint cannot be properly applied, or a colored layer having an appropriate film strength (cohesive strength) cannot be formed, and cohesive failure of the colored layer occurs. It can be said that.
In other words, by using the aqueous coloring paint in which the coloring solid content and other inorganic substances are combined and limited to less than 30 wt% in the coating composition obtained by removing the photoinitiator from the aqueous coloring paint, the aqueous coloring paint is appropriately used. It can be applied and a colored layer having an appropriate film strength (cohesive strength) can be formed, and it can be said that cohesive failure of the colored layer can be suppressed.

  In the above, the present invention has been described with reference to the first to third embodiments. However, the present invention is not limited to the above-described embodiments, and it can be applied as appropriate without departing from the scope of the present invention. Nor.

  For example, in each of Examples 1 to 3, as a water-dispersed colorant, a colored processed pigment manufactured by Dainichi Seika Co., Ltd., a trade name AF color white was used, and an aqueous colored paint (colored layer) was white. However, as a water-dispersed colorant, AF color white, AF color black, AF color yellow, and AF color red (all of which are pigmented pigments manufactured by Dainichi Seika Co., Ltd., trade names) are used as a water-based coloring paint. Even when the (colored layer) was dark, the same results as in Examples 1 to 3 could be obtained.

Moreover, in this Example 2, since the water-based colored paint does not contain an inorganic substance in addition to the colored solid content, the weight of the colored solid content is set to W1. However, an inorganic material (such as extender pigment) may be contained in the water-based colored paint in addition to the colored solid content. In this case, the combined weight of the colored solid content and the other inorganic material is W1.
Further, in Example 3, an extender pigment was added in addition to the water-dispersed colorant in producing the water-based colored paint, but a color pigment may be added instead of the extender pigment.

In Examples 1 to 3, an aqueous resin composition (specifically, product name LR8983, manufactured by BASF) containing a photocurable aqueous resin (urethane acrylate) having an average molecular weight of 10,000 was used. Any aqueous resin composition containing a photocurable aqueous resin having a molecular weight of 1000 or more can be suitably used.
Specifically, instead of LR8983, an aqueous resin composition (specifically, product name LR9005, manufactured by BASF) containing a photocurable aqueous resin (urethane acrylate, MFT 0 ° C.) having an average molecular weight of 1600 was used. Even in the case, the same results as in Examples 1 to 3 could be obtained.

Furthermore, even when an aqueous resin composition (specifically, product name LR8949, manufactured by BASF) containing a photocurable aqueous resin (urethane acrylate, MFT 0 ° C.) having an average molecular weight of 2500 is used, Examples 1 to 3 were used. The same result was obtained.
Further, even when an aqueous resin composition (specifically, Shin-Nakamura Chemical Co., Ltd., trade name RP-116EH) containing a photocurable aqueous resin (MFT 85 ° C.) having an average molecular weight of 100,000 is used, Example 1 The same result as that of ~ 3 could be obtained.
Furthermore, even when an aqueous resin composition (specifically, trade name Bihydrol UVVPLS2280 manufactured by Sumika Bayer Urethane Co., Ltd.) containing a photocurable aqueous resin (MFT 20 ° C.) having an average molecular weight of 200,000 is used, Example 1 The same result as that of ~ 3 could be obtained.

  In particular, when an aqueous colored paint containing a photocurable aqueous resin having an average molecular weight of 1600 or more and 15000 or less is used, the surface of the colored layer can be suitably made tack-free by simply drying with hot air. It was. Specifically, in the case of using an aqueous colored paint produced by adding either LR9005 (average molecular weight 1600) or LR8949 (average molecular weight 2500), the aqueous colored paint (LR8983 of Examples 1 to 3) was added. The surface of the colored layer could be suitably brought into a tack-free state only by drying with hot air to the same extent as the average molecular weight of 10,000).

  In Examples 1 to 3, an aqueous resin composition containing a photocurable aqueous resin (urethane acrylate) having an MFT of 0 ° C. (specifically, product name LR8983 manufactured by BASF) was used. Any aqueous resin composition containing a photocurable aqueous resin at 100 ° C. or lower can be suitably used. As described above, even when an aqueous resin composition containing a photocurable aqueous resin having an MFT of 85 ° C. (specifically, trade name RP-116EH manufactured by Shin-Nakamura Chemical Co., Ltd.) was used. The same result was obtained. Furthermore, even when an aqueous resin composition containing an MFT 20 ° C. photocurable aqueous resin (specifically, Sumika Bayer Urethane Co., Ltd., trade name: Bihydrol UVVPLS2280) was used, the same results as in Examples 1 to 3 were obtained. I was able to get it.

Further, even when an aqueous resin composition (specifically, trade name RP-116EH + 2 manufactured by Shin-Nakamura Chemical Co., Ltd.) containing a photocurable aqueous resin (average molecular weight 100,000) having an MFT of 68 ° C. is used. Results similar to 1 to 3 were obtained.
Furthermore, even when an aqueous resin composition (specifically, trade name RP-116EH + 5, manufactured by Shin-Nakamura Chemical Co., Ltd.) containing a photocurable aqueous resin (average molecular weight 100,000) having an MFT of 38 ° C. was used. Results similar to 1 to 3 were obtained.
Further, even when an aqueous resin composition (specifically, Shin-Nakamura Chemical Co., Ltd., trade name RP-116ES) containing a photocurable aqueous resin (average molecular weight 100,000) having an MFT of −45 ° C. is used. The same results as in Examples 1 to 3 were obtained.

  Among these, when an aqueous colored paint containing a photocurable water-based resin having an MFT of 60 ° C. or lower was used, a colored layer coating film could be suitably formed simply by drying with hot air. Specifically, in the case of using a water-based colored paint produced by adding any of Bihydrol UVVPLS 2280 (MFT 20 ° C.), RP-116EH + 5 (MFT 38 ° C.), or RP-116ES (MFT-45 ° C.), it is dried with hot air. Only by this, it was possible to suitably form a coating film of the colored layer.

  In particular, when an aqueous colored paint containing a photocurable aqueous resin having an MFT of 0 ° C. or lower was used, it was possible to more suitably form a coating film of the colored layer only by drying with hot air. Specifically, when the water-based colored paint produced by adding RP-116ES (MFT-45 ° C.) is used, it is about the same as the water-based colored paint of Examples 1 to 3 (LR 8983 added, MFT 0 ° C.). By simply drying with hot air, it was possible to form a colored layer coating more suitably.

In Examples 1 to 3, a clear layer composed of three layers of undercoat, intermediate coat, and topcoat was formed. However, the number of clear layers is not limited to three, and may be any number of layers. .
In Examples 1 to 3, as the clear paint for forming the clear layer, a light curable paint was used for the undercoat, intermediate coat, and topcoat. However, the intermediate coating and the top coating are not limited to the photo-curing type paint, and any curing type paint such as a thermosetting type may be used.
Moreover, in Examples 1-3, although various adjuvants, such as antiseptic | preservative, were added, it is sufficient if it adds suitably as needed, and it is not necessarily required to add.

It is a table | surface which shows the substance used for manufacture of the water-based coloring paint for samples AD. It is a table | surface which shows the evaluation of the component of the water-based coloring coating material for samples AD, and a coated material. It is a table | surface which shows the substance used for manufacture of the water-colored coating material for samples EJ. It is a table | surface which shows the evaluation of the component of the water-based coloring paint for samples EJ, and a coated material. It is a table | surface which shows the substance used for manufacture of the water-based coloring paint for samples K-P. It is a table | surface which shows the evaluation of the component of the water-colored coating material for samples K-P, and a coated material.

Claims (11)

A photocurable aqueous resin;
Colored solids,
A photoinitiator;
A water-based coloring paint containing
In the paint component obtained by removing the photoinitiator from the aqueous colored paint, the colored solid content is 12 wt% or more,
The photocurable water-based resin is an aqueous colored paint having an average molecular weight of 1000 or more and a minimum film forming temperature of 100 ° C. or less. The water-based colored paint according to claim 1,
An aqueous colored paint containing less than 30 wt% of the colored solid content and other inorganic substances in a paint component obtained by removing the photoinitiator from the aqueous colored paint. The water-based colored paint according to claim 1 or 2,
The weight W1 combined with the colored solid content and other inorganic substances, and the weight W2 of the photocurable aqueous resin are:
A water-based colored paint satisfying the relationship of 0.12 <W2 / W1 <1.2. The water-based colored paint according to any one of claims 1 to 3,
An aqueous colored paint comprising 0.15 parts by weight or more of the photoinitiator with respect to 100 parts by weight of a paint component obtained by removing the photoinitiator from the aqueous colored paint. The water-based colored paint according to any one of claims 1 to 4,
The water-based colored paint, wherein the photoinitiator is a visible light cleavage type photoinitiator that can be cleaved by visible light. A substrate;
A colored layer formed by photocuring the water-based colored paint according to any one of claims 1 to 5 applied to the surface of the substrate;
A clear coating containing a photocurable resin applied to the surface of the colored layer, a clear layer obtained by photocuring,
With
A coated product in which molecules constituting the photocurable aqueous resin of the colored layer and molecules constituting the photocurable resin of the clear layer are bonded to each other, and the colored layer and the clear layer are in close contact with each other. An aqueous colored paint containing a photocurable aqueous resin, a colored solid content, and a photoinitiator, wherein the colored solid content is 12 wt% or more in the paint component obtained by removing the photoinitiator from the aqueous colored paint, The above-mentioned photocurable water-based resin has an average molecular weight of 1000 or more and a water-based colored paint having a minimum film-forming temperature of 100 ° C. or less is applied to the surface of the substrate, and moisture is removed by heat drying without photocuring. A coloring step for forming a colored layer;
A clear layer forming step in which a clear paint containing a photocurable resin is applied to the surface of the colored layer and photocured together with the colored layer to form a clear layer. It is a manufacturing method of the paint according to claim 7,
The said water-based colored paint is a manufacturing method of the coating material which contains less than 30 wt% of the said coloring solid content and another inorganic substance in the paint component remove | excluding the said photoinitiator from the said water-colored paint. It is a manufacturing method of the paint according to claim 7 or 8,
The water-based colored paint has a weight W1 that combines the colored solid content and other inorganic substances, and a weight W2 of the photocurable aqueous resin.
The manufacturing method of the coating material formed by satisfy | filling the relationship of 0.12 <W2 / W1 <1.2. It is a manufacturing method of the paint according to any one of claims 7 to 9,
The said water-based colored paint is a manufacturing method of the coating material which contains the said photoinitiator 0.15 weight part or more with respect to 100 weight part of coating components remove | excluding the said photoinitiator from the said water-colored paint. It is a manufacturing method of the paint according to any one of claims 7 to 10,
In the coloring step, a method for producing a coated product in which the water-based colored paint is applied at a rate of 2.5 g / (30 cm) ² or more.

Images