JPH11286627A - Resin composition for powder coating material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a composition excellent in weather resistance, acid resistance, adhesion, etc., by using a specified amount of a specified vinyl copolymer having a glycidyl group and a specified silyl group in the molecule and having a specified glass transition temperature and a specified number-average molecular weight and an aliphatic dibasic acid as the essential components. SOLUTION: There is provided a composition essentially consisting of (D) a resin composition comprising (A) a vinyl copolymer having a silyl group of the formula and a glycidyl group and/or (B) a vinyl copolymer having a silyl group of the formula and (C) a vinyl copolymer containing a glycidyl group and (E) an aliphatic dibasic acid, wherein the glass transition temperature of A, B, or C is 40-100 deg.C, the number-average molecular weight is 2,000-20,000, and A and/or D are each used in an amount of at least 20 wt.% based on the total of the crosslinkable polymers. In the formula, R<1> is a 1-10C alkyl, a 6-10C aryl, or a 7-10C aralkyl; X is H, a halogen, OH, a (thio)alkoxyl, phenoxy, an acyloxy, aminoxy, a ketoximate, or the like; and a is 0-2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a resin composition for powder coatings. More specifically, for example, relates to a resin composition for powder coatings suitably used for automotive parts, industrial machinery, steel furniture, building interior and exterior, home appliances and the like, and more specifically, excellent water resistance, appearance, heat Curability, impact resistance,
The present invention relates to a resin composition for powder coatings that exhibits mechanical strength and the like of a coating film and exhibits extremely excellent weather resistance.

[0002]

2. Description of the Related Art Conventionally, for painting automotive parts, industrial machines, steel furniture, interior and exterior of buildings, home electric appliances, etc., acid-
A paint mainly containing an ester resin or an epoxy resin by epoxy crosslinking is used. However, although the paint is relatively inexpensive, there is a problem that the weather resistance is extremely reduced when used outdoors.

As a paint having excellent weather resistance outdoors, there is a paint using a fluorine resin. However, in this case, the cost jumps greatly and is not practical.

[0004] In addition, since the influence on the global environment is regarded as important, solvent-based paints are being shunned by the generation of a large amount of volatile components, and it is necessary to replace solvent-based paints with powder paints.

[0005] Polyester resins, which are often used in powder coatings, have a good balance of coating film properties, but have insufficient weather resistance. On the other hand, an acrylic resin is used to improve weather resistance, but a physical property balance as high as that of a polyester resin cannot be obtained. Acrylic resins tend to be harder and more brittle than polyester resins, and their mechanical properties and the like are inferior to polyester resins.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide an ester resin or an epoxy resin by the above-mentioned acid-epoxy crosslinking which has been frequently used. Overcoming the shortcomings of resin, not only has excellent weather resistance, but also clears environmental issues,
It is another object of the present invention to provide a powder coating having a new crosslinking type, which can be manufactured at low cost. By using the method of the present invention, it is possible to obtain a coating film having mechanical properties that cannot be realized by a conventional acrylic resin.

[0007]

SUMMARY OF THE INVENTION The present invention provides a novel resin composition having the following constitution, thereby achieving the above object. 1) A vinyl copolymer having both a silyl group and a glycidyl group represented by the following general formula (1) in one molecule (A)
Component and / or the following component (D) and the component (E) which is an aliphatic dibasic acid are essential components, and the component (A) or the component (B) is a silyl represented by the following general formula (1). Group as the main crosslinkable group, the component (A), the following (B)
The component or the following component (C) has a glass transition temperature of 40 to
A resin for powder coating, wherein at 100 ° C., the number average molecular weight is 2,000 to 20,000, and the component (A) and / or the component (D) is at least 20% by weight of the whole crosslinkable polymer. Composition. Component (D): a resin composition of the following component (B) and the following component (C): Component (B): a vinyl copolymer containing a silyl group represented by the following general formula (1): Component (C) : Vinyl copolymer containing glycidyl group

[0008]

Embedded image (Wherein R ¹ is an alkyl group having 1 to 10 carbon atoms, 6 carbon atoms)
At least one group selected from the group consisting of an aryl group having 10 to 10 and an aralkyl group having 7 to 10 carbon atoms,
In the case of a plurality, they may be the same or different. X is a hydrogen atom, a halogen atom, a hydroxy group, an alkoxy group, a phenoxy group, a thioalkoxy group, an acyloxy group, an aminoxy group, a ketoximate group, an amino group,
It is at least one group selected from the group consisting of an amide group and an alkenyloxy group, and when there are a plurality of groups, they may be the same or different. a is an integer of 0 to 2. 2) The component (A) is a vinyl monomer having a silyl group represented by the general formula (1).
1 to 30 parts by weight of component (b), which is a vinyl monomer having a glycidyl group, and component (c), which is a copolymerizable vinyl monomer other than component (a) and component (b) The resin composition for powder coating according to 1), which is a vinyl copolymer obtained by copolymerizing 88 to 40 parts by weight. 3) The powder according to any one of 1) and 2), wherein the component (B) contains at least one silyl group represented by the general formula (1) in one molecule. Resin composition for paint. 4) The resin composition for a powder coating according to any one of 1) to 3), wherein the component (B) has at least one glycidyl group in one molecule. 5) The resin composition for a powder coating according to any one of 1) to 4), wherein the component (C) contains at least two glycidyl groups in one molecule. 6) The powder according to any one of 1) to 5), wherein the component (C) has at least one silyl group represented by the general formula (1) in one molecule. Resin composition for paint. 7) The weight ratio of the component (B) to the component (C) in the component (D) is (B) component: (C) component = 5: 95 to 95:
5. The resin composition for a powder coating according to any one of 1) to 6), wherein the composition is 5. 8) The resin composition for a powder coating according to any one of 1) to 7), wherein X in the general formula (1) is an alkoxy group. 9) The component (A) or the component (B) is 3- (meth)
Acryloxypropyltrimethoxysilane, 3- (meth) acryloxypropyltriethoxysilane, 3-
One kind of a vinyl monomer containing a silyl group selected from the group consisting of (meth) acryloxypropylmethyldimethoxysilane and 3- (meth) acryloxypropylmethyldiethoxysilane, or a mixture of two or more thereof The resin composition for powder coating according to any one of 1) to 8), wherein the resin composition is a copolymer of 10) Component (A) or component (C) is glycidyl (meth) acrylate, 2-methylglycidyl (meth)
A glycidyl group-containing vinyl monomer selected from the group consisting of acrylates and allyl glycidyl ethers;
The resin composition for a powder coating material according to any one of 1) to 9), wherein the resin composition is obtained by copolymerizing a seed or a mixture of two or more thereof. 11) The aliphatic dibasic acid of the component (E) is one kind of a compound represented by the following general formula (2) or a mixture of two or more kinds thereof. The resin composition for powder coating according to any one of the above.

[0009]

Embedded image(Where R^TwoIs a linear or branched C1-C20
It is an alkylene group. 12) The component (E) is the component (A) and / or
Is 1 to 30 parts by weight per 100 parts by weight of component (D)
In any one of 1) to 11),
The resin composition for powder coating according to the above. The component (A) is usually a silyl group represented by the general formula (1).
Component (a) which is a vinyl monomer containing glycidin
Component (b), which is a vinyl monomer containing
Copolymerizable vinyl other than component (a) and component (b)
It is produced using the component (c) which is a system monomer. The general
The silyl group represented by the formula (1) is the same molecule as the component (A)
One or more kinds of X can be present in the same or different molecules.
You. Further, the component (A) contains the silyl group and / or
Vinyl system without or with glycidyl group
Introduced silyl or glycidyl groups into copolymer
It is also possible to make. The silicon represented by the general formula (1)
Component (a), which is a vinyl monomer containing a hydroxyl group, is generally
There is no particular limitation as long as it has a silyl group represented by the formula (1).
Is, for example, CH_Two= CHSi (OCH_Three)_Three, CH_Two= C
HSi (CH_Three) (OCH_Three)_Two, CH_Two= C (CH_Three) S
i (OCH_Three)_Three, CH_Two= C (CH_Three) Si (CH_Three)
(OCH_Three)_Two, CH_Two= CHSi (OC_TwoH_Five)_Three, CH_Two
= CHSi (OC_ThreeH₇)_Three, CH_Two= CHSi (OC
_FourH₉)_Three, CH_Two= CHSi (OC₆H₁₃)_Three, CH_Two= C
HSi (OC₈H₁₇)_Three, CH_Two= CHSi (OC
_TenH_{twenty one})_Three, CH_Two= CHSi (OC₁₂H_{twenty five})_Three, CH_Two=
CHSi (OCH_TwoCH_TwoOCH_Three)_Three, CH_Two= CHCO
O (CH_Two)_ThreeSi (OCH_Three)_Three, CH_Two= CHCOO
(CH_Two)_ThreeSi (CH_Three) (OCH_Three)_Two, CH_Two= C (C
H_Three) COO (CH_Two)_ThreeSi (OCH_Three)_Three, CH_Two= C
(CH_Three) COO (CH_Two)_ThreeSi (CH_Three) (OC
H_Three)_Two, CH_Two= CHCOO (CH_Two)_ThreeSi (OC
_TwoH_Five)_Three, CH_Two= CHCOO (CH_Two)_ThreeSi (CH_Three)
(OC_TwoH_Five)_Two, CH _Two= C (CH_Three) COO (CH_Two)_Three
Si (OC_TwoH_Five)_Three, CH_Two= C (CH_Three) COO (C
H_Two)_ThreeSi (CH_Three) (OC_TwoH_Five)_Two, CH_Two= CHCO
O (CH_Two)_ThreeSi (OCH_TwoCH_TwoOCH_Three)_Three, CH_Two=
CHCOO (CH_Two)_ThreeSi (CH_Three) (OCH_TwoCH_TwoO
CH_Three)_Two, CH_Two= C (CH_Three) COO (CH_Two)_ThreeSi
(OCH_TwoCH_TwoOCH_Three)_Three, CH_Two= C (CH_Three) COO
(CH_Two)_ThreeSi (CH_Three) (OCH_TwoCH _TwoOCH_Three)_Two,
CH_Two= C (CH_Three) COO (CH_Two)_TwoO (CH_Two)_ThreeSi
(OCH_Three)_Three, CH_Two= C (CH_Three) COO (CH_Two)_TwoO
(CH_Two)_ThreeSi (CH_Three) (OCH _Three)_Two, CH_Two= C (C
H_Three) COO (CH_Two)₁₁Si (OCH_Three)_Three, CH_Two= C
(CH_Three) COO (CH_Two)₁₁Si (CH_Three) (OCH_Three)
_Two, CH_Two= CHCH_TwoOCO (ort-C₆H_Four) COO
(CH_Two)_ThreeSi (OCH_Three)_Three, (Where ort-C₆H_Four
Is an orthophenylene group) CH_Two= CHCH_TwoOCO
(Ort-C₆H_Four) COO (CH_Two)_ThreeSi (CH_Three)
(OCH_Three)_Two, CH_Two= CH (CH_Two)_FourSi (OCH_Three)
_Three, CH_Two= CH (CH_Two)₈Si (OCH_Three)_Three, CH_Two=
CHO (CH_Two)_ThreeSi (OCH_Three)_Three, CH_Two= CHCH_Two
O (CH_Two)_ThreeSi (OCH_Three)_Three, CH_Two= CHCH_TwoOC
O (CH_Two)_TenSi (OCH_Three)_Three, CH_Two= CH (par
a-C₆H _Four) Si (OCH_Three)_Three, (Where para-C
₆H_FourIs a paraphenylene group) CH_Two= CH (par
a-C₆H_Four) Si (CH_Three) (OCH_Three)_Two, CH_Two= C
(CH_Three) (Para-C₆H_Four) Si (OCH_Three)_Three, C
H_Two= C (CH_Three) (Para-C₆H_Four) Si (CH_Three)
(OCH_Three)_TwoAn alkoxysilyl group-containing monomer such as C;
H_Two= CHCOO (CH_Two)_ThreeSi (CH_Three) C_l2, CH_Two
= CHCOO (CH_Two) _ThreeSiCl_Three, CH_Two= C (C
H_Three) COO (CH_Two)_ThreeSi (CH_Three)_TwoCl, CH_Two= C
(CH_Three) COO (CH_Two)_ThreeSi (CH_Three) Cl_Two, CH_Two
= C (CH_Three) COO (CH_Two)_ThreeSiCl_ThreeHaroshi, etc.
Ryl group-containing monomer; CH_Two= C (CH_Three) COO (C
H_Two)_ThreeSi (OH)_Three, CH_Two= C (CH_Three) COO (C
H_Two)_ThreeSi (CH_Three) (OH)_TwoContains silanol groups such as
Monomer; CH_Two= C (CH_Three) COO (CH_Two)_ThreeSi (O
COCH_Three)_ThreeAcetoxysilyl group-containing monomers such as
I can do it.

Of these, alkoxysilyl group-containing monomers are particularly preferred in terms of cost and stability. For example, 3- (meth) acryloxypropyltrimethoxysilane and 3- (meth) acryloxypropyltrimethoxysilane are preferred. At least one selected from the group consisting of ethoxysilane, 3- (meth) acryloxypropylmethyldimethoxysilane, and 3- (meth) acryloxypropylmethyldiethoxysilane, or a mixture of two or more of these. . Here, “(meth) acryloxy” means “methacryloxy or acryloxy”. Note that the term “(meta)” used in the following also means the same notation.

One or more of these components (a) may be used in combination, and at least one silyl group represented by the general formula (1) is introduced into one molecule of the component (A). The component (a) may be copolymerized as described above. The component (a) is preferably copolymerized in an amount of 11 to 30 parts by weight based on 100 parts by weight of the component (A). More preferably, 11 to
27 parts by weight, particularly preferably 12 to 25 parts by weight, may be copolymerized. If the amount of the component (a) is less than 11 parts by weight, the curing properties of the resin composition of the present invention, the mechanical strength, durability and weather resistance of the coating film are poor. The storage stability of the resin decreases.

The glycidyl group-containing vinyl monomer of component (b) is not particularly limited, and includes, for example, glycidyl (meth) acrylate, 2-methylglycidyl (meth) acrylate, allyl glycidyl ether and the like. At least one selected from the group, or two of these
And the like.

One or more of these components (b) may be used in combination, and preferably 1 to 30 parts by weight of 100 parts by weight of component (A) obtained using these monomers. Polymerized. It is more preferred that the copolymerization be carried out, more preferably 2 to 26 parts by weight, particularly preferably 5 to 25 parts by weight. If the amount of component (b) copolymerized is less than 1 part by weight, the mechanical properties of the coating film will be poor, and if it exceeds 30 parts by weight, the smoothness will decrease.

The other copolymerizable vinyl monomer as the component (c) is not particularly limited. Examples thereof include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, and isobutyl. (Meta)
Vinyl monomers such as acrylate, benzyl (meth) acrylate and cyclohexyl (meth) acrylate; aromatic hydrocarbon vinyl monomers such as styrene, α-methylstyrene, chlorostyrene, 4-hydroxystyrene and vinyltoluene Acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride,
Acids having a polymerizable carbon-carbon double bond, such as α, β-ethylenically unsaturated carboxylic acids such as crotonic acid, fumaric acid, and citraconic acid; styrene sulfonic acid, and vinyl sulfonic acid; or salts thereof (alkali Metal salts, ammonium salts, amine salts, etc.); acid anhydrides such as maleic anhydride or half esters thereof with a linear or branched alcohol having 1 to 20 carbon atoms; dimethylaminoethyl (meth) acrylate, dimethylaminopropyl (Meth) acrylates having an amino group such as (meth) acrylate and diethylaminoethyl (meth) acrylate; (meth) acrylamide, α-ethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, N,
N-dimethylacrylamide, N-methylacrylamide, acryloylmorpholine or their hydrochloric acid,
Acetate; vinyl ester and allyl ester compounds such as vinyl acetate, vinyl propionate, and diallyl phthalate;
Nitrile group-containing vinyl monomers such as (meth) acrylonitrile; 2-hydroxyethyl (meth) acrylate;
2-hydroxypropyl (meth) acrylate, 2-hydroxyethyl vinyl ether, N-methylol (meth) acrylamide, hydroxystyrene, 2-hydroxy-3-phenoxypropyl acrylate (manufactured by Toa Gosei Chemical Co., Ltd., trade name: ARONIX M-) 5700),
Hydroxyl-containing vinyl monomers such as hydroxyl-modified vinyl-modified hydroxyalkyl vinyl monomers; hydroxyalkyl esters of α, β-ethylenically unsaturated carboxylic acids such as hydroxyalkyl esters of (meth) acrylic acid; Phosphoric ester group-containing vinyl compounds or vinyl compounds such as (meth) acrylate containing urethane bond or siloxane bond; AS-6, AN-6, AA-6, A
Methacryloyl group-containing macromonomers such as B-6 and AK-5 (all manufactured by Toa Gosei Chemical Co., Ltd.); and others such as vinyl methyl ether, vinyl chloride, vinylidene chloride, chloroprene, propylene, butadiene, and N-vinylimidazole. And vinyl monomers.

The component (A) has a silyl group represented by the general formula (1) as a main crosslinkable group. In the component (A), the number of silyl groups is 5 relative to the total number of crosslinkable groups.
It is preferably at least 0%, more preferably at least 70%, particularly preferably at least 80%.

As the method for producing the component (A), known polymerization methods such as bulk polymerization, suspension polymerization, solution polymerization and the like can be used. Solution polymerization using a radical initiator is preferred.

The polymerization solvent used in the solution polymerization includes hydrocarbons (toluene, xylene, n-hexane, cyclohexane, etc.), acetates (ethyl acetate, butyl acetate, etc.), and alcohols (methanol, ethanol, etc.).
Non-reactive solvents such as isopropanol, n-butanol, ethers (ethyl cellosolve, butyl cellosolve, cellosolve acetate, etc.), ketones (methyl ethyl ketone, ethyl acetoacetate, acetylacetone, diacetone alcohol, methyl isobutyl ketone, acetone, etc.) If so, there is no particular limitation.

The initiator used in the solution polymerization is not particularly limited, but may be an organic peroxide such as benzoyl peroxide or tert-butyl peroxide, 2,2'-azobisisobutyronitrile, 2,2 '-Azobis (4-methoxy-2,4
-Dimethylvaleronitrile), 2,2′-azobis (2
Radical initiators such as azo compounds such as -cyclopropylpropionitrile) and 2,2'-azobis (2-methylbutyronitrile) are preferred.

In the above solution polymerization, if necessary, n
-Dodecyl mercaptan, t-dodecyl mercaptan,
n-octyl mercaptan, n-octadecyl mercap
Tan, 3-mercaptopropyltrimethoxysilane, 3
-Mercaptopropyltriethoxysilane, 3-merca
Ptopropylmethyldimethoxysilane, 3-mercapto
Propylmethyldiethoxysilane, (H_ThreeCO)_ThreeSi-
SS-Si (OCH _Three)_Three, (H_ThreeCO)_ThreeSi-S_Three−
Si (OCH_Three)_Three, (H_ThreeCO)_ThreeSi-S_Four-Si (O
CH_Three)_Three, (H_ThreeCO)_ThreeSi-S₆-Si (OCH_Three)_Three
The molecular weight can be adjusted using a chain transfer agent such as
You. In particular, a chain transfer having an alkoxysilyl group in the molecule.
Agents such as 3-mercaptopropyltrimethoxy
If a run is used, the terminal of the silyl group-containing acrylic copolymer
May be introduced with an alkoxysilyl group.

In the above solution polymerization, a predetermined amount of the above-mentioned monomers, initiator, chain transfer agent and the like are added to a polymerization solvent, polymerization is carried out, and the solvent is removed under reduced pressure. A) The component is obtained.

The number average molecular weight of the component (A) is from 2000 to 2000.
20,000, and preferably in the range of 3,000 to 10,000. When the molecular weight is less than 2,000, it becomes difficult for the coating film to exhibit sufficient mechanical physical properties.
When it is larger than 000, there is a problem that the smoothness of the coating film is inferior. Further, the glass transition temperature of the component (A) is 4
It is 0-100 degreeC, Preferably it is 50-80 degreeC.
When the temperature is lower than 40 ° C., the storage stability of the powder coating is inferior,
On the other hand, when the temperature is higher than 100 ° C., there is a problem that the smoothness of the coating film is inferior. The component (B) can be produced by copolymerizing the component (a) and the component (c).
The component (a) is preferably copolymerized in an amount of preferably 1 to 30 parts by weight based on 100 parts by weight of the component (B). More preferably, 3 to 25
It is preferred that the copolymer be copolymerized by weight, particularly preferably 5 to 25 weight parts. When the amount of the component (a) is less than 1 part by weight, the curing properties of the resin composition of the present invention, the mechanical strength, durability, and weather resistance of the coating film are poor.
These components (a) that reduce the storage stability of the resin include:
Species or two or more of them may be used in combination, and the component (a) may be copolymerized so that at least one silyl group is introduced into one molecule of the component (B). The component (B) is
It is also possible to produce a vinyl copolymer having no silyl group or having a silyl group by introducing a silyl group into the vinyl copolymer.

The component (B) may be a silyl group represented by the general formula (1) alone as a crosslinkable functional group, but when the compound has both a silyl group and a glycidyl group, it contains a glycidyl group. One or a mixture of two or more of the component (b), which is a vinyl monomer, may be used, and preferably 1 to 50 parts by weight based on 100 parts by weight of the component (B). More preferably, 3 to 40 parts by weight, particularly preferably 5 to 40 parts by weight.
It is preferred that the copolymer be copolymerized in an amount of up to 30 parts by weight. The component (C) can be produced by copolymerizing the components (b) and (c). Furthermore, when the silyl group represented by the general formula (1) is used, the component (a) may be copolymerized. The component (b) is preferably copolymerized in an amount of preferably 1 to 50 parts by weight based on 100 parts by weight of the component (C). More preferably, the copolymer is copolymerized in an amount of 3 to 40 parts by weight, particularly preferably 5 to 30 parts by weight. (B) the amount of copolymerizing the component is 1
If less than parts by weight, the curing properties of the resin composition of the present invention,
If the mechanical strength of the coating film is inferior, and if it exceeds 50 parts by weight, the storage stability and smoothness of the resin decrease.

These components (b) may be used alone or in combination of two or more. The component (C) preferably contains at least two glycidyl groups in one molecule. The components may be copolymerized. Further, the component (C) can also be produced by introducing the glycidyl group into a vinyl copolymer having no or already having the glycidyl group. The component (C) may be a glycidyl group alone as the crosslinkable functional group. However, when the glycidyl group and the silyl group are used in combination, one or a mixture of two or more of the component (a) may be used. Well, the component (C) 10
Preferably 0 to 30 parts by weight of the copolymer is copolymerized. More preferably 2 to 26 parts by weight, particularly preferably 5 to 25 parts by weight.
It is preferred to be copolymerized by weight.

The component (B) or the component (C) has a number average molecular weight of 2,000 to 20,000, preferably 3 to 20,000.
000 to 10,000. Molecular weight 2000
If it is less than 2,000, it is difficult for the coating film to exhibit sufficient mechanical properties, and if it is more than 20,000, there is a problem that the coating film has poor smoothness. Further, the glass transition temperature of the component (B) or the component (C) is from 40 to 100 ° C, preferably from 50 to 80 ° C. When the temperature is lower than 40 ° C., the storage stability of the powder coating is inferior.
When it is higher, there is a problem that the smoothness of the coating film is inferior.
As the method for producing the component (B) or the component (C), known polymerization methods such as bulk polymerization, suspension polymerization, and solution polymerization can be used as in the case of the component (A). Solution polymerization using a radical initiator such as a peroxide or an azo compound is preferred from the viewpoint of easiness.

The resin composition of the component (D) comprises a mixture of the components (B) and (C), and the weight ratio of the components (B) and (C) is as follows: ) Component =
5:95 to 95: 5 is preferred. More preferably 10:
90-90: 10, particularly preferably 15: 85-85:
Mix at 15.

The component (A) and / or the component (D) form a siloxane bond by the action of moisture and can be crosslinked and cured. In addition, other cross-linkable and curable polymers (including homopolymers and copolymers; and, as cross-linkable groups, including silyl groups, epoxy groups, hydroxyl groups, etc.), for example, epoxy resins, polyester resins, acrylic resins, A silicone resin or the like may be used in combination. When other crosslinkable curable polymers are used in combination, component (A) and / or component (D) is 20% by weight of the entire crosslinkable curable polymer (including component (A) and / or (D)). % Or more,
30% by weight is preferred, 50% by weight is more preferred,
80% by weight or more is particularly preferred. The aliphatic dibasic acid of the component (E) is not particularly limited,
The compound represented by the general formula (2) is preferable, and various compounds having different carbon numbers of R ² can be used in combination. R
² is a linear or branched alkylene group having 1 to 20 carbon atoms, preferably having 4 to 18 carbon atoms, and is preferably linear.

The component (E) includes, for example, adipic acid, sebacic acid, azelaic acid, dodecanedioic acid and the like. From the viewpoint of balance of various physical properties such as storage stability and mechanical strength, sebacic acid, Dodecane diacid is preferred. The aliphatic dibasic acid of the component (E) is preferably used in an amount of 1 to 30 parts by weight, more preferably 2 to 2 parts by weight, per 100 parts by weight of the component (A) and / or the component (D).
5 parts by weight, particularly preferably 3 to 20 parts by weight, are used.
When the amount of the component (E) is less than 1 part by weight, the curability and mechanical properties of the coating film become insufficient. When the amount is more than 30 parts by weight, the storage stability and the smoothness deteriorate. .

The ratio of the number of glycidyl groups in the component (A) and / or the component (D) to the number of carboxyl groups of the aliphatic dibasic acid in the component (E) is 1: 3.
３3: 1 is preferable, and a range of 1: 2 to 2: 1 is more preferable.

In the composition of the present invention, the aliphatic dibasic acid can serve as a catalyst for hydrolysis / condensation of the silyl group represented by the general formula (1). Crosslinking and acid
Epoxy cross-linking occurs at the same time, but a curing catalyst can be added to further promote cross-linking of the silyl group. As the curing catalyst, any curing catalyst can be used without particular limitation as long as it can accelerate the hydrolysis reaction of the silyl group represented by the general formula (1) and can promptly cause a condensation reaction. Examples thereof include a mixture or a reaction product with a nitrogen-containing compound, phosphoric acid or phosphoric acid esters, and an organic metal compound.

Specific examples of the curing catalyst include, for example, dodecylbenzenesulfonic acid, p-toluenesulfonic acid,
Organic sulfonic acid compounds such as -naphthalenesulfonic acid and 2-naphthalenesulfonic acid; the organic sulfonic acid compounds and nitrogen-containing compounds (for example, 1-amino-2-propanol, monoethanolamine, diethanolamine,
-(Methylamino) ethanol, 2-dimethylethanolamine, 2-amino-2-methyl-1-propanol, diisopropanolamine, 3-aminopropanol, 2-methylamino-2-methylpropanol, morpholine, oxazolidine, 4, Mixtures or reactants with 4-dimethyloxazolidine, 3,4,4-trimethyloxazolidine, etc .; phosphoric acid, monomethyl phosphate, monoethyl phosphate, monobutyl phosphate, monooctyl phosphate, monododecyl phosphate, dimethyl phosphate, diethyl phosphate,
Phosphoric acid or phosphoric acid ester such as dibutyl phosphate, dioctyl phosphate, didodecyl phosphate; propylene oxide, butylene oxide, cyclohexene oxide, glycidyl methacrylate, glycidol, acrylic glycidyl ether, 3-glycidoxypropyltrimethoxysilane, 3-glycide Epoxy compounds such as xypropyltriethoxysilane, 3-glycidoxypropyltrimethyldimethoxysilane, Cardura E manufactured by Yuka Shell Epoxy, Epicoat 828 and Epicoat 1001 manufactured by Yuka Shell Epoxy, and phosphoric acid and / or phosphoric acid. Or an addition reaction product with a monophosphate; hexylamine, di-2-ethylhexylamine, N, N-dimethyldodecylamine, DABC
Amines such as O, DBU, morpholine and diisopropanolamine; reactants of these amines with acidic phosphate esters; alkaline compounds such as sodium hydroxide and potassium hydroxide; benzyltriethylammonium chloride or bromide, tetrabutylammonium Quaternary ammonium salts such as chloride or bromide, and phosphonium salts; divalent tin compounds such as tin octylate and tin stearate, dibutyltin dioctoate,
Dibutyltin dilaurate, dibutyltin diacetate, dibutyltin diacetylacetonate, dibutyltin bistriethoxysilicate, dibutyltin distearate, dibutyltin compounds such as dibutyltin malate, dioctyltin diversate, dioctyltin dilaurate, dioctyltin distearate, dioctyltin malate Organic titanate compounds such as tetramethoxytitanium and tetrastearyloxytitanium; organic aluminum compounds such as aluminum isopropoxide and aluminum acetylacetonate; zirconia stearate and zirconium tetraacetylacetate Organic zirconium compounds such as nates.

Of these, organic titanate compounds and organic zirconium compounds are preferred from the viewpoint of curability during baking.

These curing catalysts may be used alone or in combination.

The amount of the curing catalyst used is 0.0 to 100 parts by weight of the component (A) and / or the component (D).
The amount is preferably 1 to 15 parts by weight, more preferably 0.1 to 10 parts by weight. When the amount is less than 0.01 part by weight, there is no effect of accelerating the crosslinking of the silyl group.

[0034] The resin composition for powder coatings may contain, if necessary, resins such as polyester, epoxy and acrylic, inorganic pigments such as titanium dioxide, carbon black, iron oxide and chromium oxide, and phthalocyanine-based and quinacdrine-based resins. Additives such as organic pigments, coloring aids, spreading agents and defoamers, ultraviolet absorbers, antistatic agents and antiblocking agents can be added. The mixing ratio of these additives can be appropriately selected according to the required characteristics, and they can be used as a mixture.

The production of the powder coating is carried out, for example, by using a heating roll,
It is prepared by using a melt kneader such as a kneader, melting and kneading the resin composition for a powder coating of the present invention containing the above additives as necessary, cooling, and then pulverizing. Alternatively, a curing catalyst, a pigment, an additive, and the like are added to a solution after polymerization of the component (A) and / or the component (D), and the mixture is mixed to obtain a resin composition for powder coating of the present invention. Can be used.

The powder coating obtained in this manner is applied to a substrate by a known method such as electrostatic coating or fluid immersion coating. The thickness of the coating film can be appropriately selected as needed, and is usually 20 to 200 μm, preferably 40 to 150 μm.
μm is good. When the thickness is less than 20 μm, the coating film tends to be uneven, and when the thickness is more than 200 μm, there is a problem that the coating film tends to have irregularities.

The obtained coated product is usually at 150 to 200 ° C.
By baking at a temperature of about 5 minutes to 1 hour, it can be sufficiently cured, and a cured product (coating film) having excellent physical properties such as weather resistance and acid resistance can be formed. Fifteen
When the temperature is lower than 0 ° C or shorter than 5 minutes, the coating film is not sufficiently cured. When the temperature is higher than 200 ° C or longer than 1 hour, workability deteriorates and costs such as utility costs increase. Problem arises.

The composition of the present invention is used, for example, for building interiors and exteriors such as aluminum siding and fences, road materials such as guardrails, and home appliances such as air conditioners and refrigerators.

Next, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples. In addition, the part shown below shall show a weight part unless there is particular notice. The analysis values, characteristic values, and performance of the coating film in the examples were measured or evaluated by the following methods. Analytical values (1) Number average molecular weight of polymer Measured by gel permeation chromatography (GPC). Using a Waters 600 GPC system, chloroform was used as the mobile phase and the flow rate was 1 m.
L / min. The column temperature was measured at 40 ° C. The number average molecular weight was calculated using polystyrene as a standard sample. (2) Glass transition temperature Differential scanning calorimeter (DSC, Shimadzu Corporation DSC-
50 type) under a nitrogen atmosphere at a heating rate of 5 ° C./mi.
n and determined. Characteristic value and performance of coating film (1) Smoothness The appearance of the coating film was visually evaluated. ◎: extremely good, ○: good, Δ: slightly uneven, ×:
(2) Weather Resistance The appearance of the coating film after irradiation for 3000 hours with a sunshine weather meter was visually evaluated. ◎: extremely good, ○: slightly glossy, Δ: glossy,
X: cracking, peeling, and chalking (3) Acid resistance The coating film appearance after immersing the coating film in 0.1 N sulfuric acid at room temperature for 24 hours was visually evaluated. ◎: extremely good, ○: slightly glossy, Δ: glossy,
×: cracking, peeling (4) Curability 1 g of the baked composition was wrapped in a 200-mesh stainless steel wire gauze, immersed in acetone for 24 hours, and the weight change of the composition was examined. 1
00%. ◎: 90% or more, ：: 90 to 80%, Δ: 80 to 70
%, ×: 70% or less (5) Adhesion The adhesion was evaluated by a grid tape method according to JIS K5400. ◎: No missing portion, ○: Within 5% of missing portion, Δ: 5% of missing portion
１５15%, ×: 15% or more of defective part (6) Storage stability The gel was stored at 40 ° C. for one month, and the change in the gel fraction before and after storage was examined, and used as an index of storage stability. ◎: increase in gel fraction within 5%, ：: 5 to 10%, Δ:
10 to 15%, ×: 20% or more Resin Production Examples 1 to 10 A reaction vessel equipped with a stirrer, a reflux condenser, a nitrogen gas inlet tube and a dropping funnel was charged with 50 parts of toluene, and charged with 110 parts of nitrogen while introducing nitrogen gas. After the temperature was raised to ° C., a monomer mixture (shown in parts) containing the copolymer components shown in Table 1 was dropped at a constant rate over 5 hours by a dropping funnel. After completion of the dropwise addition of the mixture, 0.5 parts of 2,2′-azobisisobutyronitrile,
A mixture of 10 parts of toluene was dropped at a constant speed in 1 hour. After completion of the dropwise addition, the mixture was further heated at 110 ° C. for 1 hour and then cooled. By distilling off the solvent from the resin solution under reduced pressure, solid-state resins (α-1) to (α-3), (β-1) to (β-3),
(Γ-1) to (γ-3) and (δ-1) were obtained.

[0040]

[Table 1] (In the table, TSMA is 3-methacryloxypropyltrimethoxysilane, TESMA is 3-methacryloxypropyltriethoxysilane, MMA is methyl methacrylate, BA is butyl acrylate, ST is styrene, and GMA is glycidyl methacrylate. , HEMA represents 2-hydroxyethyl methacrylate, and AIBN represents 2,2′-azobisisobutyronitrile.) Examples 1 to 20 Resins (α-1) to (α-3), (β-1) ~ (Β-
3) Using (γ-1) to (γ-3), each was mixed in accordance with the formulations (shown in parts) in Tables 3 and 4, and the resulting mixture was subjected to KRC kneader manufactured by Kurimoto Iron Works Co., Ltd. After melt-kneading at 120 ° C. and cooling, the mixture is finely pulverized using a bantam mill manufactured by Hosokawa Micron Corporation to obtain a powder coating (ε-1)
(Ε-20) was produced. The obtained powder coating is coated to a thickness of 0.
Film thickness of 50-60μm on 8mm zinc phosphate treated steel plate
The coating was performed using an electrostatic coating machine manufactured by Nippon Wagner Spray Tech Co., Ltd., and baked at 180 ° C. for 20 minutes to form a coating film. The results of evaluating the performance of the obtained coating film are shown in Tables 2 and 3.

[0041]

[Table 2] (In the table, TiO ₂ indicates a titanium dioxide (trade name: TAIPEK CR90) manufactured by Ishihara Sangyo Co., Ltd., and Modaflow indicates a leveling agent manufactured by Monsanto Co., USA.)

[0042]

[Table 3] (In the table, TiO ₂ indicates a titanium dioxide (trade name: Taipaque CR90) manufactured by Ishihara Sangyo Co., Ltd., and Modaflow indicates a leveling agent manufactured by Monsanto Co., USA) Comparative Examples 1 to 3 In a similar manner, the powder coating (ε
-21) to (ε-23). Table 4 shows the results of evaluation of the performance of the coating film obtained by coating in the same manner as in the examples.
It was shown to.

[0043]

[Table 4] In the table, TiO ₂ is titanium dioxide (trade name: TAIPEK CR90) manufactured by Ishihara Sangyo Co., Ltd., and blocked isocyanate is blocked isophorone diisocyanate (trade name: VESTAGON B) manufactured by Daicel Huls Co., Ltd.
1065), Modaflow is a leveling agent manufactured by Monsanto Co., USA. )

[0044]

According to the present invention, excellent weather resistance, acid resistance,
It is possible to provide a powder coating having a new cross-linking form, which has appearance, adhesion, and mechanical strength, clears environmental problems, and can be manufactured at low cost.

Claims (12)

[Claims] 1. A component (A) and / or a component (D) which is a vinyl copolymer having both a silyl group and a glycidyl group represented by the following general formula (1) in one molecule: The component (E) which is a dibasic acid is an essential component, and the component (A)
The component or the following component (B) has a silyl group represented by the following general formula (1) as a main crosslinkable group, and the component (A), the component (B) or the component (C) has a glass transition temperature. At 40-100 ° C, the number average molecular weight is 2000-200
00, and the component (A) and / or the component (D) accounts for 20% by weight or more of the whole crosslinkable polymer. Component (D): a resin composition of the following component (B) and the following component (C): Component (B): a vinyl copolymer containing a silyl group represented by the following general formula (1): Component (C) ： Vinyl copolymer containing glycidyl group (Wherein R ¹ is an alkyl group having 1 to 10 carbon atoms, 6 carbon atoms)
At least one group selected from the group consisting of an aryl group having 10 to 10 and an aralkyl group having 7 to 10 carbon atoms,
In the case of a plurality, they may be the same or different. X is a hydrogen atom, a halogen atom, a hydroxy group, an alkoxy group, a phenoxy group, a thioalkoxy group, an acyloxy group, an aminoxy group, a ketoximate group, an amino group,
It is at least one group selected from the group consisting of an amide group and an alkenyloxy group, and when there are a plurality of groups, they may be the same or different. a is an integer of 0 to 2. ) 2. The component (a) wherein the component (A) is a vinyl monomer having a silyl group represented by the general formula (1).
1 to 30 parts by weight, 1 to 30 parts by weight of component (b), which is a vinyl monomer having a glycidyl group, and a copolymerizable vinyl monomer other than components (a) and (b) ( The resin composition for a powder coating material according to claim 1, wherein the resin composition is a vinyl copolymer obtained by copolymerizing c) 88 to 40 parts by weight of the component. 3. The component according to claim 1, wherein the component (B) contains at least one silyl group represented by the general formula (1) in one molecule. A resin composition for powder coatings. 4. The component (B) has at least one glycidyl group per molecule.
4. The resin composition for a powder coating according to any one of items 3 to 3. 5. The composition according to claim 1, wherein said component (C) contains at least two glycidyl groups in one molecule.
5. The resin composition for a powder coating according to any one of items 4 to 4. 6. The method according to claim 1, wherein the component (C) has at least one silyl group represented by the general formula (1) in one molecule. A resin composition for powder coatings. 7. The weight ratio of component (B) to component (C) in component (D) is as follows: component (B): component (C) = 5:
The resin composition for powder coating according to any one of claims 1 to 6, wherein the ratio is 95 to 95: 5. 8. The resin composition according to claim 1, wherein X in the general formula (1) is an alkoxy group. 9. The component (A) or component (B) may be
(Meth) acryloxypropyltrimethoxysilane, 3
-(Meth) acryloxypropyltriethoxysilane,
One or more of silyl group-containing vinyl monomers selected from the group consisting of 3- (meth) acryloxypropylmethyldimethoxysilane and 3- (meth) acryloxypropylmethyldiethoxysilane The mixture of the above is copolymerized, characterized in that
9. The resin composition for a powder coating according to any one of 8). 10. The vinyl monomer containing a glycidyl group selected from the group consisting of glycidyl (meth) acrylate, 2-methylglycidyl (meth) acrylate, and allyl glycidyl ether as the component (A) or (C). The resin composition for powder coating according to any one of claims 1 to 9, wherein the resin composition is obtained by copolymerizing one kind of a body or a mixture of two or more kinds thereof. 11. The method according to claim 11, wherein the aliphatic dibasic acid as the component (E) is one kind of a compound represented by the following general formula (2) or a mixture of two or more kinds thereof. 1 to
11. The resin composition for a powder coating according to any one of 10 above. Embedded image (In the formula, R ² is a linear or branched alkylene group having 1 to 20 carbon atoms.) 12. The method according to claim 1, wherein the component (E) is used in an amount of 1 to 30 parts by weight based on 100 parts by weight of the component (A) and / or the component (D). The resin composition for powder coating according to claim 1 or 2.