JP3339140B2 - Resin composition for powder coating - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a novel and useful resin composition for powder coatings. More specifically, the present invention comprises an active energy ray-curable compound, a thermosetting resin, and a curing agent for the thermosetting resin, respectively, as essential coating film forming components, In particular, the present invention relates to an extremely practical resin composition for powder coatings having excellent coating film appearance, solvent resistance, and scratch resistance.

[0002]

2. Description of the Related Art In general, powder resin coatings are applied to automobile parts and electric appliances, and in particular, in recent years, the demand for them is increasing more and more due to resource saving and low pollution.

[0003] However, compared to conventional thermosetting solvent coatings, powdered resin coatings are particularly difficult to improve the smoothness of the coating film, especially when using solvent-resistant coatings. And inferior in terms of abrasion resistance, and conversely, if the degree of crosslinking of the coating film is increased to improve the solvent resistance and the abrasion resistance, this time, the smoothness becomes inferior. Had the disadvantage of becoming

[0004]

SUMMARY OF THE INVENTION However, in view of the above-mentioned various disadvantages in the prior art, the present inventors have improved the smoothness of a conventional thermosetting powder coating material, In addition, the inventors of the present invention have intensively researched a powder coating resin composition having extremely improved solvent resistance, abrasion resistance, and the like, which is extremely practicable.

[0005] Accordingly, the problem to be solved by the present invention is, in part, an extremely high practicality, in particular, excellent in coating film appearance, especially, smoothness, solvent resistance and scratch resistance. It is an object of the present invention to provide a resin composition for powder coatings, which is also a major object of the present invention.

The inventors of the present invention have conducted intensive studies with the aim of solving the problems to be solved by the invention as described above. As a result, the active energy ray-curable compound and the glycidyl group-containing vinyl copolymer have been studied. And a resin composition for a specific powder coating, which comprises the curing agent for the glycidyl group-containing vinyl copolymer, achieves the above object, and solves the above-mentioned problems. Now that the invention has been found, the present invention has been completed.

That is, the present invention basically provides an active energy ray-curable compound (A), a glycidyl group-containing vinyl copolymer (B), and a curing agent for the resin (B). It contains an aliphatic dibasic acid (C) having 4 to 20 carbon atoms, and is particularly excellent in coating film appearance, particularly, smoothness, solvent resistance, scratch resistance, and the like. An object of the present invention is to provide a highly practical resin composition for powder coatings.

[0008]

First, the above-mentioned active energy ray-curable compound (A) used in the present invention includes an ethylenically unsaturated bond-containing resin (hereinafter, this ethylenically unsaturated bond is polymerized). The active energy ray-curable compound (A) is only a typical example.

A polymerizable unsaturated group-containing modified polyester resin obtained by condensing (meth) acrylic acid with a polyester resin, a polymerizable unsaturated group-containing polyurethane resin, a polymerizable unsaturated group-containing epoxy resin, Vinyl resin containing a polymerizable unsaturated group (among others, acrylic resin containing a polymerizable unsaturated group), silicone resin containing a polymerizable unsaturated group, or melamine resin containing a polymerizable unsaturated group.

Among them, the glass transition temperature is about 5
Resins in the range of 0 to about 100C are preferred and can be used.

Further, the active energy ray-curable compound (A) includes an active energy ray-curable monomer,
Of course, an active energy ray-curable oligomer can also be used.

Among them, particularly representative ones are exemplified by esterified products of (meth) acrylic acid and monohydric alcohols having 1 to 28 carbon atoms. Examples include methyl acrylate,
Methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-butyl acrylate, iso-butyl acrylate, iso-butyl methacrylate, ter acrylate
t-butyl, tert-butyl methacrylate, purpyl acrylate or propyl methacrylate,

Or octyl acrylate, octyl methacrylate, lauryl acrylate, lauryl methacrylate, 2-ethylhexyl acrylate, 2-methacrylic acid
Ethylhexyl, 2-ethylhexyl methacrylate,
Cyclohexyl acrylate, cyclohexyl methacrylate, stearyl acrylate, stearyl methacrylate,
Benzyl acrylate or benzyl methacrylate is included.

Further, styrene, vinyl toluene, α-
Various vinyl aromatic compounds such as methylstyrene, chlorostyrene and divinylbenzene; various vinyl esters such as vinyl acetate; various vinyl halides such as vinyl chloride; methyl Various vinyl ethers represented by vinyl ether, vinyl isobutyl ether and 2-ethylhexyl vinyl ether; various cyano group-containing vinyl monomers represented by (meth) acrylonitrile; It can be used as a system monomer.

Further, various carboxyl group-containing monomers such as (meth) acrylic acid; 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl methacrylate and 2-hydroxypropyl acrylate; Various hydroxyl-containing monomers;

Addition reaction products of various polyisocyanate compounds such as butyl isocyanate and phenyl isocyanate with various hydroxyl group-containing monomers described above; phosphoric acid and various hydroxyl group-containing monomers as described above An addition reaction product with the compound; or various monomers having a nitrogen-containing heterocycle such as vinylpyrrolidone and vinylpyridine are also included.

Further, only typical representative examples of the polymerizable unsaturated oligomer include diethylene glycol diacrylate, diethylene glycol dimethacrylate, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, propylene glycol diacrylate, and propylene glycol. Including dimethacrylate,

1,3-butanediol diacrylate,
1,3-butanediol dimethacrylate, 1,4-butanediol diacrylate, 1,4-butanediol dimethacrylate, neopentyl diacrylate, neopintyl glycol dimethacrylate, 1,6-hexanediol diacrylate, 1, 6-hexanediol dimethacrylate,

Various dicarboxylic acids such as trimethylolpropane trimethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, pentaerythritol tetraacrylate, tricyclodecane dialcohol diacrylate, tricyclodecane dialcohol dimethacrylate -, Tri- or tetravinyl compounds;

A product obtained by reacting acrylic acid and / or methacrylic acid with the above-mentioned addition product of polyhydric alcohol and ethylene oxide; to the above-mentioned addition product of polyhydric alcohol and ε-caprolactam , A product obtained by reacting acrylic acid and / or methacrylic acid; or a phosphorus-containing polymerizable unsaturated oligomer.

As described above, various monomers, oligomers or resins containing a polymerizable unsaturated group include:
Of course, each of them may be used alone or in combination of two or more.

When the active energy ray-curable compound (A) is cured, an electron beam or an ultraviolet ray can be used as the active energy ray, respectively. It is necessary to add a photopolymerization initiator in advance.

As such a photopolymerization initiator, ordinary photoinitiators of the type that are excited by irradiation with ultraviolet rays to generate radicals are used. Among them, only particularly typical ones are exemplified. If you stop, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin n-butyl ether, benzoin isopropyl ether, benzoin n-propyl ether,

Α-Hydroxyisobutylphenone, benzophenone, Michler's ketone, p-methylbenzophenone, acetophenone, 1-hydroxy-1-cyclohexylacetophenone, 2-chlorothioxanthone, anthraquinone, phenyl disulfide, 2-nitrofluorene and the like.

These photopolymerization initiators can be used alone or
Of course, the photopolymerization initiator may be used in an amount of about 0.1 to 10 parts by weight, based on 100 parts by weight of the active energy ray-curable compound (A). Is appropriate.

In order to accelerate the photopolymerization reaction by these photopolymerization initiators, a photosensitizer may of course be used in combination with the photopolymerization initiator. As typical examples of sensitizers, tertiary amines such as triethylamine, triethanolamine and 2-dimethylaminoethanol, alkylphosphines such as triphenylphosphine, and β-thiodiamine Examples thereof include alkyl phosphine-based photosensitizers such as glycol, and thioether-based photosensitizers such as β-thiodiglycol.

These photosensitizers may be used alone or in combination of two or more.
The compounding amount is about 0.1 to about 100 parts by weight of the active energy ray-curable compound (A).
About 1 to 10 parts by weight is appropriate.

On the other hand, in the case of electron beam irradiation, it is not necessary to mix a photoinitiator and a photosensitizer, respectively, as described above, in the powder coating obtained as described above. By irradiating the electron beam, if only a typical example of an electron beam source in the case of curing the powder coating is to be exemplified only, Cockcroft type, Cockcroftleton type, Bande-Graf type, resonance transformer type, Transformer type,
Various electron beam generators such as an insulating core transformer type, a dynamitron type, a linear filament type or a high frequency type can be used.

The irradiation conditions of the electron beam at this time vary depending on the thickness of the coating film obtained by applying the composition of the present invention, but generally, a dose in the range of 1 to 20 Mrad is appropriate. Yes, and preferably within a certain range.

Further, only a typical example of the ultraviolet irradiation source is a mercury lamp, a xenon lamp, a carbon arc, a metal halide lamp, sunlight, or the like.
Although there is no particular limitation, it is particularly preferable to irradiate a beam containing ultraviolet rays in the range of 150 to 450 nanometers (nm) in the air or in an inert gas atmosphere.

The above-mentioned glycidyl group-containing vinyl copolymer (hereinafter referred to as component (D)). In preparing the compound, various known and commonly used methods, such as a bulk polymerization method, a suspension polymerization method, and a solution polymerization method, can be adopted.However, after polymerization by such a method, solidification is performed. You can do it like this,
The intended glycidyl group-containing vinyl copolymer (D) can be produced by an ordinary method.

Of these, only typical ones will be exemplified, and glycidyl group-containing monomers include glycidyl methacrylate and β-glycidyl methacrylate. It is.

The other monomers to be copolymerized with the glycidyl group-containing monomer may, of course, be the same as those described above, such as those used in preparing the active energy ray-curable compound (A). Various monomers and the like can be mentioned.

At this time, the glycidyl group-containing vinyl copolymer (D) has a glass transition temperature of 50 to 1
It is within the range of 50 ° C., preferably 60 to 13
The temperature must be within the range of 0 ° C.

If the temperature is too low below 50 ° C., the stability of the resulting powder coating will inevitably deteriorate. On the other hand, if the temperature is too high above 150 ° C., the coating will become smooth. Either case is not preferred because it is difficult to obtain a film.

Further, the copolymerization ratio of the glycidyl group-containing monomers is suitably about 10 to 50% by weight, preferably about 20 to 40% by weight. .

If the amount is more than about 50% by weight, the cost becomes high, and it is impossible to improve the physical properties of the coating film.
On the other hand, when the amount is less than about 10% by weight, the degree of crosslinking of the coating film tends to be low, and it is difficult to obtain a film having desired physical properties. Not preferred.

Further, as a crosslinking agent component in the present invention, an aliphatic dibasic acid (C) having 4 to 20 carbon atoms as a curing agent is used, and in particular, dodecane diacid is used. It is particularly desirable in view of the storage stability, curability and coating film performance of the powder coating.

The amount of the curing agent (C) is such that the glycidyl group in the base resin component to which the component (C) is applied is based on the acid group present in the component (C).
The equivalent ratio of “glycidyl group / acid group” is about 0.7 to 0.7.
It is appropriate to mix the curing agent (C) so as to be 1.5.

[0041]

[0042]

[0043]

[0044]

[0045]

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

Next, the compounding amount of the active energy ray-curable compound (A) is as follows: the compound (A), the glycidyl group-containing vinyl copolymer (B),
About 5 to 58% by weight based on the total amount of 20 aliphatic dibasic acids (C), preferably 2 to 50% by weight.
A range of 0 to 50% by weight is appropriate.

If less than about 5% by weight,
In the case where the degree of cross-linking of the coating film tends to be insufficient, and when the amount is more than about 85% by weight, the flexibility of the coating film is likely to be lost.

The thus-obtained resin composition for a powder coating, that is, the powder coating, of the present invention is heated until it melts, then cured by applying an active energy ray, and further heated to a high temperature to cure. May be. Also, conversely,
First, the resin may be melted, cured by heat, and then cured by irradiation with active energy rays.

The resin composition for powder coating of the present invention, that is,
In the powder coating, if necessary, a surface conditioner, a leveling agent, a reaction diluent, an ultraviolet absorber, a light stabilizer, a cissing inhibitor, a thixotropy-imparting agent, a sensitizer, or an inert organic polymer may be blended. And you can
Of course, the use of pigments, dyes and the like within a range that does not cause curing inhibition is also possible.

The resin composition for powder coating of the present invention, that is,
As a coating material (substrate) to which the powder coating can be applied, only typical ones are exemplified, and a cold-rolled steel sheet, a hot-dip galvanized steel sheet, an electro-galvanized steel sheet, an aluminum sheet,
Various metal plates, such as aluminum-plated plates, copper plates, copper-plated steel plates or tin-plated steel plates.

A so-called surface-treated plate in which various chemical conversion treatments such as a phosphate type and a chromate type are applied to these metal plates is also included. Even if a primer film is formed on such a metal plate or a surface-treated plate, and further applied thereon, a base coat or an intermediate coating is formed thereon to form a further coating film. The good thing is, of course.

[0058]

Next, the present invention will be described more specifically with reference examples, examples, comparative examples, applied examples and comparative applied examples. In the following, all “parts” and “%” are based on weight unless otherwise specified.

At this time, the glycidyl group-containing vinyl copolymer will be described with specific examples.

The active energy ray-curable resin (A)
Examples include “Unidick V-4350” [ultraviolet curable resin from Dainippon Ink and Chemicals, Inc.] and “T
AF ”(DAITO CHEMICAL, IND, LT
D product).

Reference Examples 1 to 4 [Preparation Example of Glycidyl Group-Containing Vinyl Copolymer (B)] 70 parts of xylene was placed in a reaction vessel equipped with a thermometer, a stirrer, a reflux condenser, and a nitrogen gas inlet tube. The air in the vessel was replaced with nitrogen gas, and the vessel was heated to reflux.

Next, a mixture comprising the monomers and the polymerization initiators as shown in Table 1 was added dropwise thereto over 4 hours, and after the completion of the addition, the mixture was refluxed for another 1 hour. The mixture is cooled down, cooled, and 0.5 parts of azobisisobutyronitrile (AIBN) is added. The mixture is kept at 100 ° C. to carry out a polymerization reaction of the remaining monomers. Was completed.

Thereafter, the solvent was removed from the polymerization solution thus obtained to obtain a solid target copolymer. Hereinafter, this is abbreviated as resin (B-1). Thereafter, the respective thermosetting vinyl copolymers obtained in the following Reference Examples were sequentially converted into resins (B-2) and (B-
Abbreviations 3) and (B-4).

[0064]

[Table 1]

<< Footnotes in Table 1 >> The composition ratios of the respective raw materials are all parts by weight.

"Perbutyl O" is a peroxide manufactured by NOF Corporation.

[0067]

[Table 2]

[0068]

[0069]

[0070]

[0071]

[0072]

[0073]

[0074]

[0075]

[0076]

Examples 1 to 4 << Preparation of Paint >> First, using an active energy ray-curable compound (90 ° C.) using “Buscon kneader PR46 type” (continuous melt kneader manufactured by Buss, Switzerland) A), a glycidyl group-containing vinyl copolymer (B), and a compound having 4 to 2 carbon atoms.
And an aliphatic dibasic acid (C) of 0, respectively, in a composition ratio shown in Table 2,

Further, various additives are also blended in a predetermined amount, melt-kneaded by a conventional method, cooled, and then pulverized by a pulverizer by a conventional method. Various resin compositions for powder coatings, that is, powder coatings, were prepared by collecting the portions (passing portions) that passed through the wire mesh of the mesh.

Comparative Examples 1 to 3 In the same manner as in Examples 1 to 4 except that the composition ratios were changed as shown in Table 3, various control resin compositions for powder coating, that is, Various powder coatings for control were prepared.

Examples 1-4 Among the above examples, Examples 1-4 deal with the glycidyl group-containing vinyl copolymer / dodecanedioic acid system.

[0081]

[Table 3]

<< Footnote to Table 2 >>"V-4350" is the same as "Unidick V-4"
350 ".

"Irgacure 651" is a photoinitiator manufactured by Ciba Geigy, Switzerland.

"Kp-322" is a product of Shin-Etsu Chemical Co., Ltd.
It is a leveling agent manufactured by the company.

As the compound, a product of Takaishi Kasei Co., Ltd. was used.

This is an abbreviation of "Taipec CR-90" [titanium oxide manufactured by Ishihara Sangyo Co., Ltd.] and is a typical white pigment.

Comparative Examples 1 to 3 Among the above comparative examples, Comparative Examples 1 to 3 deal with a glycidyl group-containing vinyl copolymer / dodecanediacid system as a control.

[0088]

[Table 4]

Examples 5 to 9 This group of examples deals with the hydroxyl group-containing polyester resin / blocked isocyanate system of the group of examples.

[0090]

[Table 8]

<< Footnote to Table 7 >>"B-1530" is an abbreviation of the above-mentioned "IPDI B-1530" and is a blocked isocyanate manufactured by Huls AG, Germany.

"Cleran UI" is a blocked isocyanate manufactured by Bayer AG, Germany.

DBCTRL: Abbreviation of dibutyltin laurate, manufactured by Nitto Kasei Kogyo Co., Ltd.

"Acronal 4F" is a German BA
It is a leveling agent manufactured by SF.

Comparative Examples 4 to 6 This group of examples deals with the hydroxyl group-containing polyester resin / blocked isocyanate system of the various comparative examples.

[0096]

[Table 9]

Examples 10 to 13 and Comparative Examples 7 to 9 These examples deal with the acid group-containing polyester resin / glycidyl group-containing vinyl copolymer system of the present invention or the control, respectively. It is. That is, the glycidyl group-containing vinyl copolymer as one of the thermosetting resin (B) components is used as the curing agent (C) component.

[0098]

[Table 10]

[0099]

[Table 11]

Examples 14 to 17 and Comparative Examples 10 to 1
2. These examples deal with the system of the present invention or for comparison, a polyester resin having an acid group and a hydroxyl group / a vinyl copolymer containing a glycidyl group-block isocyanate. That is, also in this case, this glycidyl group-containing vinyl copolymer as one of the thermosetting resin (B) components is used as the curing agent (C) component.

[0101]

[Table 12]

[0102]

[Table 13]

Examples 18 to 21 and Comparative Examples 13 to 1
5 These examples deal with the acid polyester resin / epoxy resin system of the present invention or control, respectively.

[0104]

[Table 14]

<< Footnote to Table 13 >>"M-8520" means "FineDick M-852".
0 "[acid-containing polyester resin manufactured by Dainippon Ink and Chemicals, Inc .; acid value = 70 KOHmg / g, softening point = 10
8 ° C.].

"M-8841" is an abbreviation of "FINEDIC M-8841" (acid group-containing polyester resin manufactured by Dojo Co .; acid value = 26 KOHmg / g, softening point = 119 ° C.).

"Epiclon 3050" is a bisphenol A type epoxy resin manufactured by Dojo Co., having an epoxy equivalent of 800 and a softening point of 102 ° C.

"C-17Z" is an imidazole-based curing catalyst manufactured by Shikoku Chemicals.

[0109]

[Table 15]

APPLICATION EXAMPLES 1-5 This group of examples was obtained by applying a resin composition for a powder coating material of a glycidyl group-containing vinyl copolymer / dodecanediacid system to a metal sheet as a steel sheet. Clarifies the various properties of the coating film.

For this purpose, in the following manner,
Coating was carried out, and thereafter, it was cured to obtain various cured coating films.

<< Coating Method and Curing Conditions >> Coating was performed by an electrostatic coating method using “GX-375” manufactured by Onoda Cement Co., Ltd.

The base material at that time has a thickness of 0.8 mm.
In the case of a so-called enamel paint in the form of using a pigment among those shown in Table 2, a zinc phosphate-treated steel sheet is used. In the case of a so-called clear paint that does not contain a clear paint, an acrylic / melamine-based white paint is applied, and the clear paint is applied on the cured coating film.

In each case, the film thickness was 60 to 7
The coating was performed so as to have a thickness of 0 micron (μm).

On the other hand, the curing methods performed subsequent to the above-described coating are shown in Tables 4 and 5 in terms of curing temperature, curing time, and ultraviolet irradiation time, respectively.

The above "Acridic A-801"
To 100 parts of [Acrylic resin manufactured by Dainippon Ink and Chemicals, Ltd .; non-volatile content = 50%, hydroxyl value = 50], 50 parts of “Taipec CR-90” (supra) were added as a white pigment, After being mixed and dispersed by shaking with a paint shaker for 3 hours, the mixture was taken out.

Next, "Super Beckamine"
L-117-60 "(butylated melamine resin manufactured by Dainippon Ink and Chemicals, Incorporated; nonvolatile content = 60%) and 35 parts of" BYK-360 "[BYK, Germany] ] And diluted with xylene.

Then, after filtration, a predetermined steel plate was applied to a thickness of 40 μm by air spray and cured at 140 ° C. for 30 minutes.
This was used as a clear test plate.

[0119]

[Table 5]

<< Footnotes in Table 4 >> Appearance: Judgment was made by visual inspection of the painted surface. ◎ …… Smoothness is very good ○ …… Smoothness is good △ …… Skin with relatively many rounds × …… Skin with very many rounds

Gasoline resistance: About half of the test piece was immersed in gasoline, allowed to stand at room temperature for 5 hours, and the color difference (ΔE) of the test piece before and after immersion was measured.

The test machine used was "$ 80" (manufactured by Nippon Denshoku Machinery Co., Ltd.) and the gasoline used was "Idemitsu 100 unleaded high-octane gasoline" (manufactured by Idemitsu Oil Co., Ltd.). Was.

Xylol rubbing: Five pieces of gauze were piled up, moistened with xylene, rubbed 10 times with a load of 5 kg, and the degree of damage of the gauze was visually determined.

◎ ほ と ん ど 傷… ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど ほ と ん ど

Scratch resistance: A test plate was impregnated with a cleanser aqueous solution of cleanser / water = 1/1 (parts by weight) into a gauze, rubbed 20 times with a load of 2 kg, and rubbed 20 times. The gloss of the test part before and after the test (however, the specular reflectance at 20 degrees) was measured and expressed as a percentage (%) of the gloss before the test.

In this case, the gloss meter is “GM-160”.
D "[manufactured by Nakaharake Mical Co., Ltd.].

[0127] Adhesion: A 1 mm × 1 mm square on the painted surface was sharpened with a sharp blade.
00, a cut was made so as to reach the surface of the article to be coated, and the surface was stuck with adhesive cellophane tape so that no air bubbles remained. That is, the number of the remaining coating film pieces).

Impact test: The test was performed using a DuPont impact tester under the conditions that the diameter of the tip of the shooting point was 1/2 inch and the weight of the falling weight was 500 g.
5cm at maximum height (cm) without cracks
Expressed in increments.

Comparative Application Examples 1 to 3 This group of application examples was the same as the application example except that a resin composition for a control powder coating of a glycidyl group-containing vinyl copolymer / dodecane diacid was used. In the same manner as in Nos. 1 to 5, various performances of the coating film when actually applied to a metal plate as a steel plate are clarified.

[0130]

[Table 6]

[0131]

[0132]

[0133]

[0134]

[0135]

[0136]

[0137]

[0138]

[0139]

[0140]

[0141]

[0142]

[0143]

As described in detail above, the resin composition for a powder coating of the present invention uses only a conventional thermosetting powder coating. Compared to the system, it can be seen that the film is extremely practical, especially excellent in terms of coating film appearance, solvent resistance, scratch resistance and the like.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-54-11936 (JP, A) JP-A-62-559 (JP, A) JP-A-6-6016 (JP, A) JP-A-6-160 248230 (JP, A) JP-A-6-184467 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C09D 4/00-201/10

Claims (4)

(57) [Claims] 1. Active energy ray-curable compound (A)
And a glycidyl group-containing vinyl copolymer (B) and a resin having 4 to 20 carbon atoms as a curing agent for the resin (B).
A resin composition for powder coatings, comprising an aliphatic dibasic acid (C). 2. The resin composition for a powder coating according to claim 1, wherein the aliphatic dibasic acid (C) is dodecane diacid. 3. The compounding amount of the active energy ray-curable compound (A) is the compound (A) and the glycidyl.
The resin for a powder coating according to claim 1, wherein the amount is 5 to 85% by weight based on the total amount of the group-containing vinyl copolymer (B) and the aliphatic dibasic acid (C). Composition. 4. The glycidyl group-containing vinyl copolymer has a copolymerization ratio of the glycidyl group-containing monomer in a range of 10 to 50% by weight.
The resin composition for a powder coating according to claim 1, which has a glass transition temperature in a range of 0 to 90 ° C.