JP3295034B2 - Toning method of powder paint - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of toning by mixing a plurality of transparent powder coatings.

[0002]

2. Description of the Related Art In recent years, powder coatings which have high safety because they are coated with air as a medium without using a solvent and which have little influence on the environment have become widespread in the field of household appliances and the like. In general, a powder coating is produced by blending a colorant and other additives into a binder resin that forms a powder, melt-kneading, pulverizing and classifying.

[0003] A powder coating charged to a certain polarity by, for example, friction or corona discharge is electrostatically attached to the surface of a grounded object, and then heated and melted.
Alternatively, a preheated object to be coated is inserted into a powder coating suspended or fluidized in an air stream, and the powder coating is melted and spread on the surface of the coating using the preheating. By doing so, a continuous coating film is formed on the surface of the object to be coated.

[0004]

However, powder coatings are
Although it is becoming widespread in the so-called large lot painting field, which consumes a large amount of the same color paint, such as the home appliances mentioned above, the small lot painting field where multicolor paint is required little by little, Alternatively, in the field of painting or the like where fine adjustment of color is required after toning, the penetration rate is low, and at present it does not reach the level of conventional solvent-based paints.

[0005] One of the causes is that the conventional method for producing a powder coating is not suitable for small-lot production, and the tint cannot be easily adjusted as in the conventional solvent-based coating. That is, the conventional powder coating is prepared by adding a coloring agent that is toned to the target color to the binder resin that forms the powder, so that the color is previously adjusted to the predetermined color. Manufactured in.

For this reason, the conventional powder coating is suitable for coating a large lot in which a large amount of the same color paint is required. It is not suitable because the toning, as it were, is not so small, and the color cannot be easily adjusted. Therefore, in order to solve such problems and to be able to easily cope with small lot painting and color adjustment,
For example, a powder coating of a plurality of colors previously adjusted to so-called three primary colors, such as cyan (C), magenta (M), and yellow (Y), particularly a translucent powder coating colored in each color. It has been studied to formulate powder paint having a predetermined color tone by blending according to the target color tone, dry blending using a mixing device such as a rotary wing type mixer, and mixing the colors. I have.

Further, the present inventors have proposed the above three colors C, M, and Y, or particularly, an orange-based color in order to reproduce a light color or a transparent color, which is difficult to reproduce only with the above three colors. In order to reproduce the color of (C), three color transmissive powder coatings of C, R, and Y to which red (R) is added instead of magenta (M), and a clear (T) containing no colorant It was studied to perform toning with four colors including a light-transmitting powder coating.

However, in the above four-color system, when a bright color having a particularly high brightness, for example, a brightness L of 60 or more is reproduced, cyan (C), magenta (M), and red (R) are mainly among the colors. The inventors have found that there is a problem that the three-color graininess is conspicuous, that is, spots of each of the above colors are easily visible in the coating film in a size corresponding to the particle size of the powder coating material as a raw material. These studies have clarified this.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a novel powder coating material which has a wide range of reproducible colors and is capable of uniform color reproduction with less noticeable granularity even in a bright color coating film. It is to provide a color method.

[0010]

Means for Solving the Problems In order to solve the above-mentioned problems, the present inventors have made various studies, particularly on the color density and lightness of powder coating materials. As a result, in the conventional powder coating, the number of prescriptions of the coloring agent such as pigment is set relatively large, and in particular, the three color powder coatings of C, M, and R have a single color density. Is high and the lightness is low, the compounding ratio at the time of toning becomes small, and the distribution of the colorant in the coating film is uneven, so-called segregation occurs. It was clarified that the graininess was a prominent cause.

That is, although it is one of the characteristic features of the toning powder coating by dry blending, the colorant contained in each powder coating is melted by baking and integrated into a continuous coating film. However, since it hardly diffuses out of the area of the original powder coating, when only a small amount of the powder coating containing a high concentration of the coloring agent is added as described above, segregation of the coloring agent may occur. This causes a noticeable graininess in the coating film.

In order to prevent the above-mentioned segregation of the colorant from occurring, the present inventors, when reproducing a bright color having a high lightness such as a lightness L of 60 or more, use the C, M, and R colors. Instead of the three color powder coatings, light cyan (LC) and light magenta (L) whose color shades are exactly the same as each other but whose color density is reduced and lightness is improved.
As a result of studying the use of powder coatings of each color of M) and light red (LR), the present invention was completed.

That is, these light-based powder coatings have a lower color density in a single color and a higher lightness than in the prior art, so that the mixing ratio at the time of toning becomes larger than before.
For this reason, in the coating film, the colorant of each of the above colors, at a lower concentration, more widely, because it will be distributed evenly,
For example, when reproducing a vivid color having a lightness L of 60 or more, the granularity of the coating film becomes less noticeable than before.

Therefore, the method for toning a powder coating according to the present invention comprises a transparent powder coating of a plurality of colors colored with a coloring agent and a clear (T) transparent powder containing no coloring agent. a body paint, formulated in a predetermined ratio, when to toning by dry blending using a mixing apparatus, is blended with powder coating of the clear (T), as a colored powder coating, below
Characterized by using either (1) or (2)
It is.

(1) Cyan (C), magenta (M), and yellow
(Y) at least one of the three color translucent powder coatings
One type and light cyan (L) lighter in color than cyan (C)
C) and light magenta lighter in color than magenta (M)
(LM) of the two color translucent powder coatings
One kind. (2) Cyan (C), red (R), and yellow
(Y) at least one of the three color translucent powder coatings
One type and light cyan (L) lighter in color than cyan (C)
C) and light red lighter than Red (R)
(LR), at least one of the two color translucent powder coatings.
Also one kind.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below. In the toning method of the present invention, as described above, five colors of C, LC, M, LM, and Y, or C, particularly for reproducing an orange color, which are colored with a coloring agent, are used. LC, R,
A colored translucent powder coating of five colors LR and Y and a clear (T) translucent powder coating not containing a coloring agent are used.

Among the above, the LC powder coating is not limited to the above, but for example, the brightness of the original C
Those having a lightness of 1.5 to 3.0 times the powder coating of the above are preferably used. Similarly, as the LM powder coating, the brightness of the original M powder coating, also 1.5 to 3.
A value of 0 times is preferably used, and the LR powder coating is 1.5 to 3 times the brightness of the original R powder coating.
Those having 0 times are preferably used.

If the lightness of each light powder coating is less than the above range, it may not be easy to make the granularity of the coating film inconspicuous. Conversely, if it exceeds the above range, The color density becomes too light, and accurate color reproduction may not be easy. The lightness of the LC powder coating should be within the above range, especially the original C
More preferably, the lightness of the powder coating is 2.0 to 3.0 times. Similarly, the lightness of the LM powder coating is also within the above range, especially the brightness of the original M powder coating.
More preferably, the lightness of the LR powder coating is 2.0 to 3.0 times the lightness of the original R powder coating within the above range. Is more preferred.

As described above, in order to adjust the lightness of the powder paint of each light type color with respect to the original, the blending amount of the colorant may be adjusted, for example, as described later. Such a colored powder coating is, for example, a mixture obtained by preliminarily mixing a transparent binder resin, a coloring agent such as a pigment, and other additives as necessary using a dry blender, a Henschel mixer, a ball mill, or the like. , For example, a jet mill,
After melt-kneading using a Banbury mixer, a roll, a single-screw or twin-screw extrusion kneader or the like, the resulting kneaded material is cooled, pulverized, and, if necessary, classified.

The clear (T) powder coating is produced in the same manner as described above except that no coloring agent is added. Each of the above powder coatings is uniformly melted and integrated when forming a coating film by ease of dry blending or baking.
In consideration of forming a continuous and uniform coating film, it is preferable that the binder resin is formed of binder resins having excellent compatibility with each other, and it is more preferable that the binder resin is formed of the same binder resin.

When the powder paint toned by dry blending is electrostatically adhered to the surface of a grounded object to be coated, for example, in the charged state as described above, the compounding of the powder paint of each color is performed. It is preferable that the charging characteristics of the powder coatings of the respective colors are matched in advance so that the charging characteristics of the entire powder coating do not fluctuate due to the variation in the ratio.

The C, LC, M, LM, Y and T 6
Color, or C, LC, R, LR, Y and T,
Plural colors including clear, the toning method of the present invention using a translucent powder coating can be performed manually, depending on the knowledge, experience and intuition of the operator, as in the past, for example. As shown in FIG. 1, it is performed by using an automatic powder coating color toning system that automatically performs from the color measurement of the target color of the color matching to the preparation and toning of the powder coating of each color. preferable.

According to such an automatic toning system, internal factors such as a skill level, a health state and a psychological state of the worker, which affect the worker at the time of the toning work, or the kind of color to be toned (for example, There is an advantage that there is no possibility that the toning result will vary due to external factors such as light colors, etc., and environmental conditions (season, weather, time, light state, etc.) at the time of work.

In such an automatic toning system, first,
A color sample or the like of a target color is measured using a colorimeter such as a spectrophotometer [Step S1]. Next, a wavelength-reflectance curve is created from this colorimetric result [Step S
2] and then Kubelka-Munk
nk), at regular intervals (for example, 20
A K / S value, which is a ratio between the light absorption coefficient K and the scattering coefficient S, at the wavelength of (nm) is calculated [Step S3].

Next, as shown in FIG. 2, this K / S value is applied to each of the powder coatings of a plurality of colors to be used in advance by adjusting the blending ratio with the clear powder coating. , K / S values of a plurality of basic data 1 to n measured by changing the color density of the coating film [(K / S) ₁ to (K /
S) _n ] and the calculated reflectance calculated from the above isomeric matching is performed to match the spectral reflectance curves [Step S 4]. Then, the result of this isomeric matching and 3 calculated from the calculated reflectance are used. By performing a metameric match using the stimulus value and matching the three stimulus values, the compounding ratio of the powder paint of each color is calculated [Step S]
5].

Next, based on the calculation results, the powder coating materials of each color are measured using a measuring device [Step S6] and supplied to a mixing device to dry blend [Step S6].
7]. And then, dry blended powder paint,
After test coating under the same conditions as actual coating [Step S
8] The colorimeter performs colorimetry using the colorimeter, and compares the colorimetric data with the colorimetric data of the target color measured first to determine whether there is a color shift [step S9].

If there is any color misregistration in this determination, the mixing ratio of the powder paint of each color is corrected and calculated based on the two colorimetric data (step S10), and based on the result, Steps S6 to S9 are repeated again. Then, in the determination of step S9, when the color shift between the coating film and the target color is eliminated, the toning of the powder paint is completed.

As a criterion for determining the presence or absence of a color shift in step S9, for example, a color difference ΔΕ ^* between the colorimetric data of the target color and the colorimetric data of the coating film is used. Specifically, for example, a color difference ΔΕ ^* between the colorimetric data of the target color and the colorimetric data of the coating film is a color difference Δ 以下^{* that} is equal to or less than a predetermined threshold value, without any color deviation, What is necessary is just to determine that there is a color shift. The threshold value is not limited to this, but is preferably about ΔΕ ^* = 0.8.

Step S7 of the above toning method
If the dry blending process is insufficient in the dry blending process, the aggregates of the powder coating for each color are not sufficiently disintegrated. On the contrary, in this case, the granularity of the coating film becomes so large as to be visible due to the aggregation of the powder coating, which may cause defects such as color segregation, mottle, and shading. There is.

Therefore, it is necessary to set an optimum time for the dry blending, and the above-mentioned color difference ΔΕ ^* is suitably adopted as a setting standard. That is, (i) a powder paint sample used for toning is dry-blended using a mixing device in advance of toning, and the hue in the powder state of the sample in the middle is measured. Colorimetry is performed at regular intervals using a device, and the color difference ΔΕ ^* between the latest colorimetric value and the previous colorimetric value is equal to or less than a threshold value (preferably 0.8
Measure the time of dry blending required to become the following), set the dry blending time of the actual powder coating based on the data, or (ii) use a mixing device During the dry blending, the actual powder coating is sampled at regular intervals, and the hue in the powder state is measured using a colorimeter to measure the latest and previous colorimetric values. the color difference ΔΕ ^* is equal to or smaller than the threshold of the (preferably 0.8
By terminating the dry blending at the point of (below), it is possible to produce a dry blended powder coating which is free from defects such as color segregation, mottle and shading.

The components constituting the powder coating of a plurality of colors including clear, which are used in the toning method of the present invention, are not limited thereto, but include, for example, the following materials. (Binder Resin) As the binder resin, among various conventionally known resins used in powder coatings, in order to impart light transmission to the powder coating, the resin is excellent in light transmission and is applied to an object to be coated. Any of various resins that can be melted by heating at the time of application or after application to form a continuous coating film can be used.

Examples of the binder resin include, but are not limited to, polystyrene, chloropolystyrene,
Poly-α-methylstyrene, styrene-chlorostyrene copolymer, styrene-propylene copolymer, styrene-
Butadiene copolymer, styrene-vinyl chloride copolymer,
Styrene-vinyl acetate copolymer, styrene-maleic acid copolymer, styrene-acrylate copolymer (styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer Copolymer, styrene-octyl acrylate copolymer, styrene-phenyl acrylate copolymer, etc.), styrene-methacrylic ester copolymer (styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene Butyl methacrylate copolymer, styrene-phenyl methacrylate copolymer), styrene-α
Styrene resins (homopolymers or copolymers containing styrene or styrene substituents) such as methyl chloroacrylate copolymer, styrene-acrylonitrile-acrylate copolymer, acrylic acid, methyl acrylate, acrylic acid Acrylic resins [(meth) acrylic acid such as ethyl, butyl acrylate, octyl acrylate, phenyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate, phenyl methacrylate, and methyl α-chloroacrylate And a homopolymer or copolymer mainly composed of an ester thereof),
Polyvinyl chloride, low molecular weight polyethylene, low molecular weight polypropylene, ethylene-ethyl acrylate copolymer, polyvinyl butyral, ethylene-vinyl acetate copolymer,
Examples thereof include a polyester resin, an epoxy resin, and a silicone resin. These may be used alone or as a mixture of two or more.

Particularly preferred binder resins include styrene resins, acrylic resins, and polyester resins. Among them, (i)
(1):

[0034]

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[In the formula, R ¹ and R ² represent the same or different lower alkylene groups. x and y are the same or different and each represent 0 or an integer of 1 or more;
7 A diol component represented by: (ii) a dicarboxylic acid, an acid anhydride or a lower alkyl ester thereof,
(iii) Trihydric or higher polycarboxylic acid, its anhydride or lower alkyl ester, or copolycondensation with trihydric or higher polyhydric alcohol, and has a hydroxyl value (OHV) based on its acid value (AV). ) Ratio OHV / AV value is 1.
Two or more polyester resins are preferred binder resins.

In the above polyester resin, lower alkylene groups corresponding to R ¹ and R ² in the general formula (1) include, for example, methylene, ethylene, trimethylene, propylene, tetramethylene, ethylethylene, pentamethylene, hexamethylene. Examples thereof include an alkylene group having 1 to 6 carbon atoms such as methylene. X + y in the general formula (1) is 1 to 7 as described above, and preferably 3 to 5. x
When + y exceeds 7, there is a problem that the molecular weight of the diol component becomes too large and the light transmittance of the coating film is reduced.

The diol component represented by the general formula (1) includes, for example, polyoxypropylene (2.2) -2,2
-Bis (4-hydroxyphenyl) propane, polyoxypropylene (3.3) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2.0)
-2,2-bis (4-hydroxyphenyl) propane,
Polyoxypropylene (2) -polyoxyethylene (2) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (6.0) -2,2-bis (4-hydroxyphenyl) propane, etc. can give.

The dicarboxylic acids include, for example, oxalic acid, malonic acid, succinic acid, itaconic acid, glutaconic acid,
Examples include adipic acid, maleic acid, fumaric acid, citraconic acid, mesaconic acid, azelaic acid, sebacic acid, cyclohexanedicarboxylic acid, phthalic acid, isophthalic acid, terephthalic acid and the like. These dicarboxylic acids may be esters with acid anhydrides or lower alkyls. Examples of the lower alkyl include an alkyl group having 1 to 6 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, iso-butyl, s-butyl, t-butyl, n-pentyl, and n-hexyl. can give.

The polyhydric carboxylic acid having a valency of 3 or more, the acid anhydride or lower alkyl ester thereof, and the polyhydric alcohol having a valency of 3 or more are used to adjust the acid value and the hydroxyl value of the polyester resin, It is blended for the purpose of. Examples of the trivalent or higher polycarboxylic acid, its acid anhydride or lower alkyl ester include trimellitic acid, 2,5,7-naphthalene tricarboxylic acid, 1,2,4-naphthalene tricarboxylic acid, 1,2,4- Butanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methoxycarbonylpropane, tetra (methoxycarbonyl) methane, 1,2,2
7,8-octanetetracarboxylic acid and the like.

Examples of the trihydric or higher polyhydric alcohol include glycerin, 2-methyl-1,2,3-propanetriol, 1,2,4-butanetriol and 2-methyl-1,2,4-butanetriol. , 1,2,5-pentatriol, pentaerythritol, dipentaerythritol, tripentaerythritol, hexitol, sorbitol, 1,4-sorbitan, 1,2,4-benzenetriol and the like.

The polyester resin is synthesized by copolycondensation of the above components at a temperature of 180 to 250 ° C., for example, in an inert gas atmosphere. Acid value of polyester resin (A
The ratio of the hydroxyl value (OHV) to V) OHV / AV is 1.2 or more, preferably 1.2 to 50, more preferably 2 to 40. OHV / AV value is 1.2
If it is less than 1, the translucency of the resin decreases, the minimum melting temperature of the resin increases, and it becomes difficult to form a continuous coating film by heating and melting, or the fluidity of the powder coating decreases. Problem.

The acid value (AV) is calculated, for example, by dissolving a polyester resin in a mixed solvent of benzene and ethanol, titrating with potassium hydroxide, and calculating the neutralization amount. The hydroxyl value (OHV) is determined by, for example, acetylating a free acid in a polyester resin using a mixed solvent of pyridine and acetic anhydride (3.1: 1), and then titrating acetic acid bound to the resin with potassium hydroxide. It is calculated from the amount of neutralization by titration.

The polyester resin described above can be used alone, or may be blended with various previously known resins. When other resins are blended, the amount is preferably about 1 to 30% by weight based on the polyester resin. (Colorant) As the cyan (C) colorant, a phthalocyanine pigment is particularly preferably used. As a specific example of such a phthalocyanine pigment, for example, a general formula (2)
:

[0044]

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Wherein X ¹ , X ² , X ³ and X ⁴ are the same or different and each represent a hydrogen atom, a group (2a) or a group (2b):

[0046]

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Is shown. R ³ and R ⁴ are an alkylene group having 1 to 5 carbon atoms. A copper phthalocyanine pigment represented by, for example, C.I. I. Pigment Blue 15 (15: 1 to 15: 4,
A compound wherein X ¹ , X ² , X ³ and X ⁴ are all hydrogen atoms) or a derivative thereof, or a compound of the formula (3):

[0048]

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And a non-metallic phthalocyanine pigment (CI Pigment Blue 16).
The above C.I. I. Pigment Blue 15 derivatives include partially chlorinated products thereof, and barium salts of sulfonic acid of copper phthalocyanine (CI Pigment Blue 17). Examples of other cyan-based coloring agents other than the above include inorganic pigments such as navy blue (Prussian blue) and cobalt blue; I. Pigment Blue 18, C.I. I. Organic pigments such as CI Pigment Blue 16, C.I. I. Bat Blue 6, C.I. I. And dyes such as Solvent Blue 70.

In the case of the original cyan (C) powder coating, a clear color is obtained,
Further, considering that the light transmittance of the powder coating does not decrease, it is preferable that the amount is about 1 to 20 parts by weight, particularly about 2 to 8 parts by weight, based on 100 parts by weight of the binder resin. In the case of light cyan (LC) powder coating, the amount of the cyan-based coloring agent is set to be smaller than that of the original C powder coating in order to achieve the lightness magnification described above. Although the specific range depends on the brightness of the original powder coating of C, it is about 0.1 to 2.5 parts by weight, particularly about 0.5 to 2.5 parts by weight, per 100 parts by weight of the binder resin.
It is preferably about 2.0 parts by weight.

As the magenta (M) colorant, for example, a quinacridone pigment is used. Specific examples of such quinacridone pigments include, for example, those represented by the general formula (4):

[0052]

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[Wherein Q¹And Q^TwoAre the same or different
Represents a hydrogen atom, an alkyl group or an alkoxy group.
But Q¹, Q^TwoAre not simultaneously hydrogen atoms. ]
Quinacridone pigments such as C.I. I. Pigmentle
Head 122 [Q ¹And Q^TwoAre both methyl groups
Compound]. Also, other magenta other than the above
As the colorants of the tertiary system, for example, bengara, cadmium
Red, lead red, cadmium mercury sulfide, manganese purple, red mouth
Inorganic pigments such as graphite and molybdenum orange; I. Pi
Gment Red 3, C.I. I. Pigment Red 38,
C. I. Pigment Red 48: 2, C.I. I. Pigmen
Tread 49: 1, C.I. I. Pigment Red 49:
2, C.I. I. Pigment Red 50, C.I. I. Pigmen
Tread 57, C.I. I. Pigment Red 60, C.I.
I. Pigment Red 81, C.I. I. Pigment Red
90, permanent red FNG, C.I. I. Pig member
Iolet 3, C.I. I. Pigment Violet 25,
C. I. Pigment Orange 5, C.I. I. Pigmento
Range 13, C.I. I. Pigment Orange 16, etc.
Machine pigment, spiron red, indanthrene brilliant
Orange RK, Indanthrene Brilliant Orange G
Dyes such as K;

The amount of the magenta-based coloring agent is determined in consideration of the fact that the original magenta (M) powder coating gives a vivid color and does not reduce the light transmittance of the powder coating. It is preferably about 1 to 20 parts by weight, particularly about 2 to 8 parts by weight, based on 100 parts by weight of the resin. In the case of a light magenta (LM) powder coating, the amount of the magenta coloring agent is set to be smaller than that of the original M powder coating to be combined in order to achieve the above-described lightness magnification. The specific range depends on the brightness of the original M powder paint, but is approximately 100% of the binder resin.
About 0.1 to 2.5 parts by weight, especially 0.1 to 2.5 parts by weight.
It is preferably about 5 to 2.0 parts by weight.

Examples of the yellow (Y) colorant include condensed azo pigments, isoindoline pigments, and benzimidazolone pigments. Among them, the condensed azo pigment is represented by the general formula (5):

[0056]

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Wherein R ⁵ and R ⁶ are the same or different and represent an alkyl group or a halogen atom, and R ⁷ and R ⁸ are the same or different and represent a group (5a) or (5b):

[0058]

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Is shown. A compound represented by the formula: I. Pigment Yellow 93 [R ⁵ is a methyl group, R
⁶ is a chlorine atom, and R ⁷ and R ⁸ are both groups (5a)], C.I. I. Pigment Yellow 94 (R ⁵ and R ⁶ are both chlorine atoms, R ⁷ and R ⁸ are both groups (5b)
And C.I. I. Pigment Yellow 9
5 [R ⁵ and R ⁶ are both methyl groups, R ⁷ and R ⁸
Wherein both are groups (5b).

As the isoindoline pigment, for example, a compound represented by the following general formula (6):

[0061]

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Wherein Ar is a group (6a) or (6b):

[0063]

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FIG. A compound represented by the formula: I. Pigment Yellow 109 [compound wherein Ar is group (6a)], C.I. I. Pigment Yellow 110 [Ar
Is a group (6b)]. Further, as a benzimidazolone pigment, a compound represented by the formula (7):

[0065]

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(CI Pigment Yellow 154) and the like. Other yellow-based coloring agents other than the above include, for example, yellow iron oxide,
Inorganic pigments such as loess, graphite, zinc yellow, cadmium yellow, and antimony yellow; I. Pigment Yellow 1, C.I. I. Pigment Yellow 3, C.I. I. Pigment Yellow 12, C.I. I. Pigment Yellow 13,
C. I. Pigment Yellow 16, C.I. I. Pigment Yellow 17, C.I. I. Pigment yellow 55, C.I.
I. Pigment Yellow 65, C.I. I. Pigment yellow 73, C.I. I. Pigment yellow 74, C.I. I.
Pigment yellow 83, C.I. I. Pigment Yellow 97, C.I. I. Pigment Yellow 98, C.I. I. Pigment yellow 115, C.I. I. Pigment Yellow 1
30, C.I. I. Pigment yellow 133, C.I. I. Pigment yellow 138, C.I. I. Organic pigments such as C.I. Pigment Yellow 169; I. Solvent Yellow 1
6, C.I. I. Solvent Yellow 33, C.I. I. Solvent Yellow 56, C.I. I. Solvent Yellow 60,
C. I. Solvent Yellow 61, C.I. I. Solvent Yellow 162, C.I. I. Acid Yellow 1, C.I.
I. Dyes such as Acid Yellow 23;

The amount of the yellow-based coloring agent is 1 to 100 parts by weight of the binder resin in consideration of the fact that a clear color is obtained and that the light transmittance of the powder coating does not decrease.
It is preferably about 20 to 20 parts by weight, particularly preferably about 1.5 to 8 parts by weight. As the red (R) colorant, for example, a naphthol-based pigment is used. As a specific example of such a naphthol-based pigment, for example, a general formula (8):

[0068]

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(CI Pigment Red 170) and the like. Other red-based coloring agents other than the above include, for example, C.I. I. Pigment Red 5, C.I. I. Pigment Red 146, C.I.
I. Pigment Red 177, C.I. I. Pigment Red 178, C.I. I. Pigment Red 202, C.I. I.
Pigment Red 238, C.I. I. Pigment Red 2
51, C.I. I. Pigment Red 254, C.I. I. Pigment Red 255, C.I. I. Pigment Red 264
And other organic pigments.

The compounding amount of the red coloring agent is such that in the case of the original red (R) powder coating, a clear color is obtained;
Further, considering that the light transmittance of the powder coating does not decrease, it is preferable that the amount is about 1 to 20 parts by weight, particularly about 2 to 8 parts by weight, based on 100 parts by weight of the binder resin. In the case of light red (LR) powder coating, the blending amount of the red coloring agent is set smaller than that of the original R powder coating to be combined in order to achieve the above-described lightness magnification. The specific range depends on the brightness of the original R powder coating, but is about 0.1 to 2.5 parts by weight, especially about 0.5 to 0.5 parts by weight, per 100 parts by weight of the binder resin.
It is preferably about 2.0 parts by weight.

The clear (T) type powder coating is produced without adding the above-mentioned coloring agent. (Other Additives) Examples of additives other than the colorant include various conventionally known additives such as a charge control agent, a curing agent, and a leveling agent (flowing agent). Among these, the charge controlling agent is used when the powder coating is used in, for example, the above-mentioned electrostatic coating method, for example, the electrostatic coating method using a spray gun, or the electrostatic flow immersion method. And to stabilize regardless of changes in environmental conditions such as temperature and humidity, and to match the charging characteristics of each color powder coating as described above. One of a positive charge control agent and a negative charge control agent is used.

Examples of the positive charge control agent include, for example, a nigrosine electron donating dye, a metal salt of naphthenic acid or a higher fatty acid, an alkoxylated amine, a quaternary ammonium salt, an alkylamide, a chelate, a pigment and a fluorine-treated material. Activators and the like. Examples of charge control agents for controlling negative charges include electron-accepting organic complexes, chlorinated paraffins, chlorinated polyesters, polyesters having an excess of acid groups, sulfonylamine of copper phthalocyanine, aromatic oxycarboxylic acids, and aromatic dicarboxylic acids. Acids and the like.

However, in the case of a translucent powder coating, in order not to affect the color as much as possible, (a) the color is itself colorless or pale, and (b) the powder coating is not turbid. A charge controlling agent which is excellent in compatibility with the binder resin or incompatible with the binder resin but excellent in dispersibility is preferably used.

As the positive charge control agent satisfying the above conditions, quaternary ammonium salts can be mentioned, and as the negative charge control agent, aromatic oxycarboxylic acid, aromatic dicarboxylic acid and the like can be mentioned. Among the above, the quaternary ammonium salt which is a positive charge control agent includes various compounds, and in particular, the compound represented by the general formula (9):

[0075]

Embedded image

Wherein R ^a , R ^b , R ^c and R ^d are
Same or different lower alkyl group, long chain alkyl group,
A represents an alkenyl group or a benzyl group, and A ^- represents an anion. However, at least one of R ^{a to} R ^d is a long-chain alkyl group or a long-chain alkenyl group, and two are a lower alkyl group or a benzyl group. ] Are preferably used.

In the general formula (9), examples of the long-chain alkyl group corresponding to R ^{a to} R ^d include an octyl group,
Decyl group, dodecyl group, tetradecyl group, hexadecyl group, octadecyl group, eicosyl group, docosyl group, oleyl group, linolyl group, hexadecyl group and the like. Examples of the long-chain alkenyl group include, for example, a group having one or more double bonds introduced into the molecule of the long-chain alkyl group.

Examples of the anion represented by A ⁻ include molybdic acid, phosphomolybdic acid, silicomolybdic acid, chromium molybdic acid, bromomolybdic acid, tungstic acid, phosphotungstic acid, silicotungstic acid, chromium tungsten Anions, chloride ions, bromine ions, iodine ions, nitrate ions, sulfate ions derived from molybdenum atoms and inorganic acids containing tungsten atoms such as acids, bromotungstic acid, phosphotungsten / molybdic acid, and silicotungsten / molybdic acid , Perchlorate ion, benzoate ion, tetraphenylboron ion, hexafluorophosphate ion, naphtholsulfonate ion and the like.

Specific examples of the quaternary ammonium salt represented by the general formula (9) include, for example, (C ₁₆ H ₃₃ ) ₂ N ⁺
(CH ₃ ) ₂ 1/4 Mo ₈ O ₂₆ ^4- , (C ₁₆ H ₃₃ ) ₂
N ⁺ (CH ₃ ) ₂ 1/6 Mo ₇ O ₂₄ ^6- , (C
^{_{16 H 33) 2 N + (}} CH 3) 2 · 1 / 2WO 4 2- and the like, may be used by mixing one or more of them.

The charge control agent is preferably used in an amount of 1 to 10 parts by weight based on 100 parts by weight of the binder resin.
More preferably, it is 5 parts by weight. If the amount of the charge control agent is less than the above range, the effect of the addition may be insufficient.If the amount exceeds the above range, the light transmittance may decrease or the color may change. There is a possibility that. The curing agent is for curing the coating film by crosslinking the binder resin in the coating film when the powder coating is heated and melted to form a coating film. , For example, blocked isocyanates, epoxy resins,
Examples include an amino resin, an aziridine compound, and a polyvalent carboxylic acid.

A suitable range of the curing agent is set according to the equivalent of the functional group contributing to the curing reaction. If the amount of the curing agent is less than the preferred range, the effect of the addition may be insufficient.If the amount exceeds the preferred range, on the other hand, the light transmittance is reduced or the color is changed. Or The leveling agent is used to improve the fluidity of the powder coating when heated and melted to make the coating film smoother. Examples of the leveling agent include “Acronal 4F” (trade name, manufactured by BASF). "YF-3919" manufactured by Toshiba Silicone Co., Ltd. and "Modaflow 2000" manufactured by Monsanto.

The compounding amount of the smoothing agent is preferably 0.1 to 2 parts by weight based on 100 parts by weight of the binder resin.
More preferably, the amount is from 1 to 1 part by weight. If the blending amount of the leveling agent is less than the above range, the effect of the addition may be insufficient, and if it exceeds the above range, the translucency is reduced or the color is changed. There is a risk. In addition to the above, other additives such as a curing accelerator for assisting a curing reaction by a curing agent, an antifoaming agent, or an epoxy resin for enhancing corrosion resistance of a coating film are also included in the powder coating. May be blended.

(Production Method of Powder Coating) As described above, the powder coating is prepared by a pulverization method, that is, a mixture obtained by preliminarily mixing the above-mentioned components using a dry blender, a Henschel mixer, a ball mill, or the like. After melt-kneading using a mixer, a roll, a single-screw or twin-screw extrusion kneader, the obtained kneaded material is cooled and pulverized,
In addition to being manufactured by classifying as necessary,
It can also be produced by a polymerization method, a microcapsule polymerization method, a spray drying method, or the like.

The particle size of the powder coating may be the same as that of the prior art,
In consideration of the uniformity of color when two or more colors are mixed, the smaller the particle size, the more preferable it is.
m or less. In consideration of the chargeability, the ease of forming a coating film, and the difficulty of aggregation, the average particle size of the powder coating is preferably 1 μm or more within the above range.

In consideration of the balance between the above-mentioned properties, the average particle size of the powder coating should be within the above range, especially 5 to 5.
Particularly preferably, it is 20 μm. Various external additives may be added to the powder coating in order to improve the fluidity and charging characteristics thereof, and to match the charging characteristics for each color powder coating as described above.

As the external additives, aluminum oxide,
Various conventionally known external additives having a particle size of about 1.0 μm or less, for example, fine powder of metal oxide such as silicon oxide, titanium oxide, and zinc oxide, or fine particles of fluorine resin can be used. Silica-based surface treating agents containing hydrophilic or hydrophilic silica fine particles, for example, ultrafine anhydrous silica and colloidal silica are preferably used.

The amount of the external additive to be added is not particularly limited, and may be the same as the conventional one. Specifically, it is preferable to add an external additive in a total amount of about 0.1 to 3.0 parts by weight to 100 parts by weight of the powder coating before dry blending for each color.
In some cases, the amount of the external additive added may be outside this range. (Formation of coating film) Since the powder coating toned by the above-described toning method of the present invention has a light-transmitting property, it usually depends on the color of the object to be coated. In order to reproduce an accurate tint, it is preferable to form a layer of such a translucent powder coating (overcoating film) after interposing a hiding, particularly white undercoating film.

In such a case, it is appropriate to form the above-mentioned undercoating film with a powder coating material in the same manner as the overcoating film in consideration of the influence on safety and environment. As described above, various methods are conceivable as a method of laminating a base coat and a top coat, both of which are formed of a powder coating, on an object to be coated. Taking into account, the powder paint that forms the base coat and the powder paint that forms the top coat are electrostatically adhered to the work in this order, and then the work is performed. Ideally, a method of heating and heating to form both coating films at once (two-coat one-bake method) is adopted.

However, in order to carry out the two-coat one-bake method, a powder coating material, which is a base of a base coating film, is statically charged to a predetermined polarity on a grounded coating object. After the electrodeposition, it is necessary to electrostatically adhere a powder coating on which a top coat is formed in a state opposite to the above-mentioned polarity. This is because if both powder coatings are charged to the same polarity, it is impossible to form a uniform topcoat having a uniform thickness.

For example, when a powder spray gun is used, as described in Examples described later, the powder paint used as the base of the undercoat film is charged positively using a triboelectric charging gun. Then, the toned powder coating, which is the base of the overcoating film, is electrostatically adhered to the object to be coated, and is then charged negatively using a corona charging gun. It is preferable to electrostatically adhere to the coating material.

It is preferable that the powder coating material used as the base coating film contains an inorganic pigment such as titanium oxide. The use of a powder coating containing an inorganic pigment has the advantage of improving the impact resistance and chemical resistance, especially alkali resistance, of the entire coated coating film.

[0092]

[Product name ER-6680 manufactured by Nippon Ester Co., Ltd.]

-Pigment C. I. Pigment Blue 15: 3 3.0 [Ket Blue 104 (trade name, manufactured by Dainippon Ink Co., Ltd.)] -Hardener Vestagon B1530 15 (trade name, manufactured by Huls) -Curing accelerator StannOMF (trade name, manufactured by Sankyoki Gosei Co., Ltd.) 0.3 ・ Smoothing agent Dispalon PL525 1.0 (trade name, manufactured by Kusumoto Kasei Co., Ltd.) ・ Defoaming agent Benzoin 0.5 (trade name, manufactured by Midori Kagaku Co., Ltd.) ・ Epoxy resin 2.0 [Toto Kasei Co., Ltd. Epotote YD-014]
Next, 0.4 parts by weight of the produced cyan translucent powder coating material (I) was added to 0.4 parts by weight of fine powder silica as a surface treatment agent for negative charging [Nippon Aerosil Co., Ltd. R972 manufactured by WARING Co., Ltd.)
CIAL BLENDER HGB-SS] and mixed for stirring. <Cyan (C) -based translucent powder coating (II)>
C. I. Pigment Blue 15: 3, except that the blending amount was 2.0 parts by weight, in the same manner as the cyan-based translucent powder coating material (I), a slightly light-colored cyan-based translucent powder having a volume center particle diameter of 13 μm. Light powder coating (II) was produced. The lightness L of the cyan translucent powder coating material (II) was 25.20, and the lightness magnification to the cyan translucent powder coating material (I) was 1.27 times.

Next, 0.4 parts by weight of finely divided silica [R972] was added to 100 parts by weight of the powder coating material.
This was also stirred and mixed using the rotary blade type mixer described above, and provided for toning. <Light cyan (LC) -based translucent powder coating> C.I. I. Pigment Blue 15: 3 in an amount of 0.1.
Cyan translucent powder coating (I) except that it is 5 parts by weight
In the same manner as in the above, a light cyan-based translucent powder coating material having a volume center particle size of 13 μm was produced. The lightness L of the light cyan type translucent powder coating material was 49.15, and the magnification of the lightness to the cyan type translucent powder coating material (I) was 2.47 times.

Next, 0.4 parts by weight of fine powder silica [R972, supra] was added to 100 parts by weight of the powder coating material.
This was also stirred and mixed using the rotary blade type mixer described above, and provided for toning. <Magenta (M) translucent powder coating (I)>
C. I. Pigment Blue 15: 3 and the same amount (3.0 parts by weight) of C.I. I. Pigment Red 122
[KetRed 309 manufactured by Dai Nippon Ink Co., Ltd.]
A magenta translucent powder coating material (I) having a volume center particle diameter of 13 μm was produced in the same manner as in the cyan translucent powder coating material (I) except that the above was used. The lightness L of the magenta translucent powder coating material (I) was 20.88.

Next, 0.4 parts by weight of finely divided silica [R972, supra] was added to 100 parts by weight of the powder coating material.
This was also stirred and mixed using the rotary blade type mixer described above, and provided for toning. <Magenta (M) -based translucent powder coating (II)> C.I. I. Pigment Red 122, except that the blending amount was 2.0 parts by weight, in the same manner as the magenta-based translucent powder coating material (I), a slightly light-colored magenta-based translucent powder having a volume center particle diameter of 13 μm. Body paint (II) was produced. The lightness L of the magenta translucent powder paint (II) is 28.35, and the lightness magnification with respect to the magenta translucent powder paint (I) is 1.3.
It was 6 times.

Next, 0.4 parts by weight of finely divided silica [R972 described above] was added to 100 parts by weight of the powder coating material.
This was also stirred and mixed using the rotary blade type mixer described above, and provided for toning. <Light magenta (LM) -based translucent powder coating> C.I. I. Pigment Red 122 in an amount of 0.1.
Magenta translucent powder coating except for 5 parts by weight
In the same manner as in (I), a light-magenta translucent powder coating material having a volume center particle diameter of 13 μm was produced. The lightness L of the light magenta translucent powder paint was 48.55, and the lightness magnification with respect to the magenta translucent powder paint (I) was 2.33 times.

Next, 0.4 parts by weight of fine powder silica [R972, supra] was added to 100 parts by weight of the powder coating material.
This was also stirred and mixed using the rotary blade type mixer described above, and provided for toning. <Yellow (Y) -based translucent powder paint> As a pigment, C.I.
I. Pigment Blue 15: 3 and the same amount (3.0
Parts by weight) of C.I. I. Pigment Yellow 154 [trade name: Symuler Fast Yel manufactured by Ciba-Geigy Corporation]
low 4192], except that a volume center particle diameter of 13 μm was used in the same manner as in the cyan-based translucent powder coating material (I).
A yellow translucent powder coating was produced. The lightness L of the yellow translucent powder paint was 85.47.

Next, 0.4 parts by weight of finely divided silica [R972, supra] was added to 100 parts by weight of the powder coating material.
This was also stirred and mixed using the rotary blade type mixer described above, and provided for toning. <Red (R) translucent powder coating (I)>
C. I. Pigment Blue 15: 3 and the same amount (3.0 parts by weight) of C.I. I. Pigment Red 170
[Brilliant Ca (trade name) manufactured by Sanyo Pigment Co., Ltd.]
rmine 7009], except that the volume center particle diameter was 13 μm.
To produce a red translucent powder coating material (I). The lightness L of the red translucent powder coating material (I) was 23.02.

Next, 0.4 parts by weight of fine silica powder (R972 described above) was added to 100 parts by weight of the above powder coating material.
This was also stirred and mixed using the rotary blade type mixer described above, and provided for toning. <Red (R) -based translucent powder coating (II)>
C. I. Pigment Red 170 was prepared in the same manner as Red Translucent Powder Coating (I) except that the blending amount of Pigment Red 170 was 2.0 parts by weight. Body paint (II) was produced. The lightness L of the red translucent powder coating material (II) was 33.69, and the lightness magnification of the red translucent powder coating material (I) was 1.42 times.

Next, 0.4 parts by weight of fine powder silica [R972, supra] was added to 100 parts by weight of the powder coating material.
This was also stirred and mixed using the rotary blade type mixer described above, and provided for toning. <Light red (LR) translucent powder coating> C.I. I. Pigment Red 170
A light-red translucent powder coating material having a volume center particle diameter of 13 μm was produced in the same manner as in the red-type translucent powder coating material (I) except that the weight part was used. The lightness of the light-red translucent powder coating material was 46.60, and the magnification of the lightness to the red-based translucent powder coating material (I) was 2.02 times.

Next, 0.4 parts by weight of fine powder silica [R972 described above] was added to 100 parts by weight of the powder coating material,
This was also stirred and mixed using the rotary blade type mixer described above, and provided for toning. <Clear (T) -based translucent powder coating> A clear-based translucent powder having a volume center particle diameter of 13 μm in the same manner as the cyan-based translucent powder coating (I) except that no pigment was blended. A powder coating material is manufactured, and 0.4 parts by weight of fine powder silica (R972 described above) is mixed with 100 parts by weight of the powder coating material by stirring using the rotary blade mixer described above. And subjected to toning.

<< Preparation of Basic Data >> Among the powder coatings of each color produced in the preparation of the above powder coatings, LC, LM, Y
The powder paints of the four colors T and T were blended at the blending ratio (% by weight) shown in Table 1 below, and the powder paints of 21 samples that were dry-blended were used as SPCC steel plates (vertical 1
50 mm, 70 mm in width, 40.8 mm in thickness), a white powder paint was electrostatically deposited under the following condition I, and then electrostatically deposited under the following condition II.
Baking for 0 minutes, a white underlayer with a thickness of about 30 μm,
Samples of a coating film having a two-layer structure of a colored overcoat layer having a thickness of about 30 μm and made of the powder coating of each sample were prepared.

[0103]

[Table 1]

<Condition I (coating of white underlayer)> Powder supply: quantitative feeder [prototype manufactured by Mita Kogyo Co., Ltd.], rotation speed = 380 r.p.m. p. m. , Scraper angle = scale 1 ・ Substrate conveying speed: 50 mm / sec ・ Coating machine: manufactured by Barcalizing, INF pressure = 3 kg
/ Cm ² G, swirling pressure = 3 kg / cm ² G, transfer pressure =
3 kg / cm ² G ・ Gun: triboelectric gun, nozzle = fan shape ・ Booth suction air velocity: 0.59 m / sec ・ Coating distance: 300 mm ・ Amount of adhesion to SPCC steel sheet: 0.7 g <Condition II (colored overcoat layer・ Powder supply: Same as above ・ Coating object transfer speed: Same as above ・ Coating machine: Same as above ・ Gun: Corona charging gun, applied voltage = -60 kV ・ Booth suction wind speed: Same as above ・ Coating distance: Same as above ・ SPCC steel plate Next, the coating film of each sample was coated with a spectrophotometer (X-Rite manufactured by Kurabo Industries, Ltd.) as a colorimeter.
SP68] to prepare 21 basic data (wavelength-reflectance curve). Then, the 21 basic data are input to the arithmetic unit, and the respective K / S
The values [(K / S) ₁ to (K / S) ₂₁ ] were calculated, the calculated reflectance was calculated from each K / S value, and the tristimulus values were calculated from the calculated reflectance. The following was used as the white powder coating for the white underlayer. <White powder coating> As a pigment, C.I. I. Pigment Blue 15: 3, 30 parts by weight of titanium oxide (trade name: CR-90, manufactured by Ishihara Techno Co., Ltd.), and cyan-based translucent powder except that it was not classified after pulverization. paint
A white powder coating having a volume center particle size of 17 μm was produced in the same manner as (I). The white powder coating was used as a base without surface treatment.

<< Toning of Powder Coating >> Example 1 As a target color, CF0245 (Vivid Green, lightness L = 66.1) of a color card manufactured by Toyo Ink Co., Ltd. was used.
80) and CF0201 (yellow, lightness L = 84.1)
The two colors of 6) were selected, and each of the colors was measured using the above-mentioned spectrophotometer, and a wavelength-reflectance curve was created.

Then, the wavelength-reflectance curve is input to a computer in which a program for executing the above-described automatic toning system is set, and a K / S value is calculated. An isometric match is performed using the calculated reflectance obtained in the creation of the basic data, which has been recorded in the storage device of the computer, and the result of the isometric match is also recorded in the storage device in advance. Put, 3 obtained in the previous creation of basic data
A metameric match was performed using the stimulus value and the compounding ratio (% by weight) of the powder paints of the four colors LC, LM, Y and T required to reproduce the above-described target colors was calculated.

[0107] For Comparative Examples 1 and 2 comparisons, LC, original C instead of LM
(I), M (I), powder coatings of the four colors Y and T, and C (II), M (II) slightly thinner than the original, and Y
And T using four powder paints to reproduce each of the above colors. After obtaining the necessary basic data for each of them, C (I), M (I), Y and T
Of four color powder coatings (% by weight), C (II) and M (I
The mixing ratios (% by weight) of the powder coatings of the four colors I), Y and T were calculated.

The results are shown in Tables 2 and 3, respectively.

[0109]

[Table 2]

[0110]

[Table 3]

<< Evaluation of Toning >> Based on the results of Tables 2 and 3, four colors of LC, LM, Y and T, C (I), M (I), Y,
A powder paint of four colors of T or four colors of C (II), M (II), Y, and T is weighed using a weighing device, and a rotary blade type mixer as a mixing device [WARING, supra] Co., Ltd.) and dry blended for 25 seconds.

Next, each of the toned powder coating materials was first applied to one side of an SPCC steel sheet as an object to be coated with the above-mentioned I powder.
After electrostatically adhering a white powder coating under the conditions of II,
And then baked at 180 ° C. for 20 minutes to form a 30-35 μm-thick white base layer and a 30-35 μm-thick colored overcoat layer composed of each powder coating. And a coating film having a total thickness of 65 μm was prepared.

Then, the color of each coating film is measured using the spectrophotometer, and the color difference Δ の^* between the color measurement data and the color measurement data of the color card as the target color is calculated. Those with ^* less than or equal to the threshold value of 0.8 were evaluated as having no color shift (○), and those having more than 0.8 were evaluated as having color shift (×). In addition, each coating film was visually observed, and those having no noticeable graininess were evaluated as having no graininess, and those having a noticeable graininess were evaluated as having graininess. Table 4 shows the results.

[0114]

[Table 4]

From the table, four color powders of C (I), M (I), Y and T are shown.
Comparative Example 1 toned using body paint, C (II), M (II),
Comparative Example 2, which was toned using powder coatings of four colors of Y and T,
Good toning without color shift from target color was possible
But reproduces vivid colors with high brightness, as in the example above
When it did, the graininess became noticeable.

On the other hand, four colors of LC, LM, Y and T
Example 1 in which toning was performed using a powder coating was the same as in Comparative Example 1 described above.
Good toning with no color shift from target color, equivalent to 2.
It is capable of reproducing bright colors with high brightness as shown in the example.
When compared with Comparative Examples 1 and 2,
It was confirmed that a high quality coating film could be formed.

[0117]

As described in detail above, according to the present invention,
Unique effect of providing a new method of toning powder coatings that offers a wide range of colors that can be reproduced, and has a low graininess even in vivid color coatings with high lightness and that enables uniform color reproduction. It works.

[Brief description of the drawings]

FIG. 1 is a flowchart showing each step of an example of a toning method of the present invention.

FIG. 2 is a flow chart showing a step of calculating a calculated reflectance and tristimulus value from a plurality of basic data measured in advance for each of a plurality of color powder coatings to be used in the toning method.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-11-293160 (JP, A) JP-A-8-183916 (JP, A) JP-A-59-20361 (JP, A) 504431 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) C09D 7/14 C09D 5/03

Claims (4)

(57) [Claims] (1) cyan, magenta, colored with a coloring agent ;
And three of the three color translucent powder paints, yellow and yellow.
At least one and light cyan, which is lighter than cyan,
And light magenta, which is lighter than magenta.
At least one of the light powder coatings and a clear light transmitting powder coating not containing a coloring agent are blended in a predetermined ratio, and dry-blended using a mixing device, and toned. To
How to control the color of the powder coating, wherein a call. 2. A light cyan powder coating having a lightness 1.5 to 3.0 times that of a cyan powder coating, and a light magenta powder coating having a lightness , The lightness of magenta powder paint 1.5 ~
2. The method of toning a powder coating according to claim 1, wherein the method is 3.0 times. 3. Cyan, red, and orange colored with a coloring agent.
And yellow, three of the three transparent powder coatings
At least one, light cyan, which is lighter than cyan, and
Light red, lighter than red
And at least one of the powder coating, and a translucent powder coating clear containing no colorant was blended in a predetermined ratio, and then dry-blended toned to Turkey with mixing device A method for toning a powder coating, comprising: 4. A light cyan powder paint having a brightness 1.5 to 3.0 times that of a cyan powder paint, and a light red powder paint having a lightness , The lightness of red powder paint 1.5 ~
4. The method for toning a powder coating material according to claim 3 , wherein the ratio is 3.0 times.