JP2000319578A - Curable resin composition for top coating material and coated material coated with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition exhibiting excellent curability in a range from a low temperature to a high temperature and having a pot life sufficient for an operation by making the composition include a specific vinyl- based copolymer, an organometallic compound and a weak solvent. SOLUTION: This composition comprises (A) an alkoxysilyl group-containing vinyl-based copolymer, (B) 0.1-20 pts.wt., preferably 0.2-13 pts.wt., more preferably 0.5-10 pts.wt. based on 100 pts.wt. of the component A of an organometallic compound and (C) a weak solvent. A (co)polymer obtained by (co)polymerizing a monomer unit of the formula (R1 is H or a 1-10C alkyl; R2 is H, a 1-10C alkyl, a 6-10C aryl or a 7-10C aralkyl; (a) is 0-2), etc., may be cited as the component A. An organotin compound, etc., are preferable as the component B. An aliphatic hydrocarbon is preferable as the component C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a curable resin composition for paints. More specifically, for example, metals, ceramics, glass, cement, ceramic moldings, plastics,
The present invention relates to a curable resin composition for paint that can be suitably used for painting buildings, home appliances, industrial equipment, and the like made of wood, paper, fiber, and the like.

[0002]

2. Description of the Related Art Conventionally, surfaces of industrial products such as ceramic compositions, buildings made of concrete and steel, and building materials are coated with paints such as fluororesin paints, acrylic urethane resin paints and acrylic silicone resin paints. By coating, a design effect is imparted to a building, and weather resistance and the like are improved.

However, in recent years, with the deterioration of the environment mainly in urban areas, the paints have been required to further improve the stain resistance. Therefore, the present inventors have conducted intensive studies and as a result, have found a composition capable of forming a coating film having excellent stain resistance in addition to the above-mentioned weather resistance (Japanese Patent Application Laid-Open No. 7-48540). ).

[0004] However, the above-mentioned composition is excellent in weather resistance and stain resistance, but has insufficient curing properties at low temperatures, and it is necessary to increase the amount of catalyst to ensure sufficient curing properties. , Pot life was not fully satisfactory. JP-A-60-67553 discloses a composition comprising an alkoxysilane-containing polymer and a specific aluminum compound. Although this composition has improved curability and closed storage stability, it does not have sufficient open system stability (pot life) and stain resistance. JP-A-4-1
No. 17473 discloses a composition comprising an organoalkoxysilane, a silyl group-containing vinyl resin, water, a tetraalkyl silicate, and an aluminum compound. Although curability, adhesion, weather resistance, etc. are improved, when mixing and reacting organoalkoxysilanes, silyl group-containing vinyl resins, and water, a large amount of water is used. The pot life and storage stability of the closed system are not sufficient.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a curable composition for coatings which has excellent curability over a low to high temperature range and has a sufficient pot life in operation. And Furthermore, the coating film obtained from this composition can reduce the contact angle from the beginning, and is excellent in stain resistance,
It is another object of the present invention to have excellent effects on appearance such as surface gloss, luster and depth, chemical resistance, hot water resistance and the like.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in view of the above-mentioned situation, and as a result, have found that a vinyl copolymer (A) having a specific silyl group can be treated with an organometallic compound. It has been found that the above problem can be solved by blending a composition comprising (B) and a weak solvent (C).

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The curable resin composition for a top coat according to the present invention comprises a base resin having a curability at room temperature in the presence of moisture as a base resin comprising a vinyl copolymer, And / or a side chain having the general formula (1)

[0008]

Embedded image (In the formula, R ¹ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, when there are a plurality may .R ² be different even if the same is a hydrogen atom, C 1 -C ~ 1
Represents an alkyl group having 0, an aryl group having 6 to 10 carbon atoms, or an aralkyl group having 7 to 10 carbon atoms. When a plurality of aralkyl groups are present, they may be the same or different. a
Represents an integer of 0 to 2. ) Is contained. The vinyl copolymer (A) having a reactive silyl group represented by the formula (A) is contained.

Here, "the main chain consists of a vinyl copolymer chain" means that a copolymer block of a compound having a polymerizable C = C bond, such as a vinyl group or a vinylidene group, and another compound. Constitutes the main chain of the vinyl copolymer (A). Further, the main chain has at least one reactive silyl group at the terminal and / or side chain.

It is sufficient that at least one reactive silyl group is present in one molecule, but it is preferable that two to ten reactive silyl groups be present from the viewpoint of providing sufficient curability and relaxing internal stress.

In the above formula (1), R ¹ is a hydrogen atom or a group having 1 to 10 carbon atoms, preferably, for example, a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-
It is a C1-C4 alkyl group, such as a butyl group and an i-butyl group. If the alkyl group has more than 10 carbon atoms, the reactivity of the reactive silyl group is reduced. Also, when R ¹ is a group other than an alkyl group such as a phenyl group and a benzyl group, the reactivity of the reactive silyl group is reduced.

In the general formula (1), R ² is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, preferably, for example, an alkyl group having 1 to 4 carbon atoms as exemplified in the aforementioned R ¹ ;
For example, it is a monovalent hydrocarbon group selected from an aryl group preferably having 6 to 25 carbon atoms such as a phenyl group and an aralkyl group preferably having 7 to 12 carbon atoms such as a benzyl group. Among them, an alkyl group having 1 to 4 carbon atoms is preferable from the viewpoint that the composition of the present invention is excellent in curability.

In the above general formula (1), (R ¹ O) _3-a
Is such that 3-a is 1 or more and 3 or less, that is, a is 0
~ 2, but vinyl copolymer (A)
A is 0 or 1 from the viewpoint that the curability of
It is preferred that Therefore, the number of bonds of R ² is 0 to
It is preferably 1.

R ¹ O or R ² present in the general formula (1)
Is 2 or more, R ¹ or R ² contained in 2 or more
May be the same or different. Specific examples of the reactive silyl group represented by the general formula (1) include:
For example, a group contained in a monomer containing a reactive silyl group described below can be mentioned.

As the silyl group-containing vinyl monomer (a), the compound represented by the general formula (3)

[0016]

Embedded image (In the formula, R ¹ , R ² and a are the same as those described above), and those containing a monomer unit containing a reactive silyl group bonded to a carbon atom are preferable. The content ratio of the reactive silyl group-containing vinyl monomer (a) is from 1 to 90 from the viewpoint that the coating film formed using the composition of the present invention has excellent durability and strength. %, And even 3 to 70%,
In particular, it is preferably 3 to 50%.

The monomer units other than the monomer units having a reactive silyl group represented by the general formula (1) contained in the vinyl copolymer (A) include acrylic unit units described later. Units derived from monomers and units derived from other monomers used as necessary as described below.

The vinyl copolymer (A) has a number average molecular weight of from 1,000 to 3,000 from the viewpoint that the coating film formed using the composition of the present invention has excellent physical properties such as durability.
It is preferably 0, especially 3000 to 25000.

The vinyl copolymer (A) as described above is
They may be used alone or in combination of two or more.

Next, an example of a method for producing the vinyl copolymer (A) will be described.

The vinyl copolymer (A) includes, for example, a monomer containing a polymerizable double bond and a reactive silyl group (hereinafter, referred to as monomer (A-1)), (meth) acrylic acid and / or Derivatives thereof (hereinafter referred to as monomer (A-2)
) As well as those containing other monomers used as necessary. Specific examples of the monomer (A-1) include, for example,

[0022]

Embedded image General formula (4) such as

[0023]

Embedded image (Wherein, R ¹ , R ² and a are the same as those described above, and each represents an R ³ hydrogen atom or a methyl group);

[0024]

Embedded image General formula (5) such as

[0025]

Embedded image (Wherein, R ¹ , R ² , R ³ , and a are the same as above, and n is 1 to 1)
Indicates an integer of 2. A) a compound represented by the formula:

[0026]

Embedded image General formula (6) such as:

[0027]

Embedded image (Wherein, R ¹ , R ² , R ³ , a, and n are the same as described above);

[0028]

Embedded image General formula (7) such as:

[0029]

Embedded image (Wherein R ¹ , R ² , R ³ and a are the same as above, and m is 1
Which represents an integer of from 14 to 14)

[0030]

Embedded image General formula (8) such as

[0031]

Embedded image Wherein R ¹ , R ² , R ³ and a are the same as above, and P is 0
And an (meth) acrylate having a reactive silyl group bonded to a carbon atom at a terminal via a urethane bond or a siloxane bond. Among these, the compound represented by the above general formula (IV) is preferable from the viewpoint of excellent copolymerizability and polymerization stability, and excellent curability and storage stability of the obtained composition.

Specific examples of the monomer (A-2) include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, stearyl (meth) acrylate, benzyl (Meth) acrylate, cyclohexyl (meth) acrylate, 3,3,5-trimethylcyclohexyl (meth) acrylate, lauryl (meth) acrylate, isobornyl (meth) acrylate, trifluoroethyl (meth) acrylate, pentafluoropropyl (meth) Acrylate, perfluorocyclohexyl (meth) acrylate, (meth) acrylonitrile, glycidyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) a Relate, (meth) acrylamide, α-ethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N-methyl (meth) acrylamide (meth) acryloylmorpholine, 2-hydroxy Ethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, N-methylol (meth) acrylamide, Alonix M-5700, macromonomers AS-6, AN-6, AA-6, AB-6, AK-
Compounds such as 5 (these are manufactured by Toa Gosei Chemical Industry Co., Ltd.),
Placel FA-1, Placel FA-4,
Placel FM-1, Placel FM-4,
HEAC-1 (manufactured by Daicel Chemical Industries, Ltd.),
Phosphoric ester group-containing (meth) acrylic compounds such as condensation products of hydroxyalkyl esters of (meth) acrylic acid and phosphoric acid or phosphoric esters, and (meth) acrylates containing urethane bonds or siloxane bonds. No.

These monomers (A-2) may be used alone or in combination of two or more.

The amount of the monomer (A-2) to be used may be appropriately adjusted according to the kind and the amount of the monomer (A-1) to be used.
%, More preferably 30 to 90%, particularly preferably 50 to 88%.

In the present invention, for the purpose of further improving the weather resistance of a coating film formed from the obtained composition of the present invention, for example, a segment or monomer (U) formed by a urethane bond or a siloxane bond in the main chain. A-1),
A segment derived from a monomer other than the monomer (A-2) may be introduced in the production of the acrylic copolymer (A) within a range not exceeding 50%.

The monomer (A-1) and the monomer (A-
Specific examples of monomers other than 2) include, for example, aromatic hydrocarbon-based vinyl compounds such as styrene, α-methylstyrene, chlorostyrene, styrenesulfonic acid, 4-hydroxystyrene, and vinyltoluene; maleic acid, fumaric acid, itacone Acids, unsaturated carboxylic acids such as (meth) acrylic acid, their alkali metal salts, ammonium salts,
Salts such as amine salts; acid anhydrides of unsaturated carboxylic acids such as maleic anhydride; diesters and half esters of these acid anhydrides with alcohols or amines having a linear or branched chain having 1 to 20 carbon atoms; Esters of unsaturated carboxylic acids; vinyl esters and allyl compounds such as vinyl acetate, vinyl propionate and diallyl phthalate;
Amino group-containing vinyl compounds such as vinylpyridine and aminoethyl vinyl ether; amide group-containing vinyl compounds such as itaconic acid diamide, crotonic acid amide, maleic acid diamide, fumaric acid diamide, N-vinylpyrrolidone; 2-hydroxyethyl vinyl ether; Methyl vinyl ether, cyclohexyl vinyl ether, vinyl chloride, vinylidene chloride, chloroprene, propylene,
Other vinyl compounds such as butadiene, isoprene, fluoroolefin maleimide, N-vinylimidazole, and vinyl sulfonic acid are included. These may be used alone or in combination of two or more.

Further, in the coating composition of the present invention,
Non-aqueous polymer particles (NAD) obtained by non-aqueous dispersion polymerization are added to vinyl copolymer (A) as a main component, using an alkoxysilyl group-containing copolymer as a dispersion stabilizer resin. Can be. This component can achieve low viscosity and high solids of the coating composition by adding a very small amount, and can further improve the impact resistance of the cured coating film. Non-aqueous polymer particles (NA
As the monomer used in the production of D), the monomer used in the vinyl copolymer (A) can be used.

The vinyl copolymer (A) is disclosed in, for example, JP-A-54-36395 and JP-A-57-5595.
It can be produced by a hydrosilylation method described in JP-A No. 4 (1994) -204, or a solution polymerization method using a monomer containing a reactive silyl group, but contains a reactive silyl group from the viewpoint of ease of synthesis and the like. It is particularly preferable that the monomer is produced by a solution polymerization method using an azo radical polymerization initiator such as azobisisobutyronitrile using a monomer.

The solvent used in the solution polymerization method is not particularly limited as long as it is a non-aqueous solvent. Examples thereof include hydrocarbons such as toluene, xylene, n-hexane and cyclohexane; and ethyl acetate and butyl acetate. Acetates; cellosolves such as ethyl cellosolve and butyl cellosorb; ether esters such as cellosolve acetate; ketones such as methyl ethyl ketone, ethyl acetoacetate, acetylacetone, methyl isobutyl ketone, acetone; methanol, isopropyl alcohol;
alcohols such as n-butanol, isobutanol, hexanol and octanol;

When the above-mentioned weak solvent (C) is used in the polymerization of the vinyl copolymer (A), the low-temperature curability can be further improved.

In the solution polymerization, if necessary, for example, n-dodecyl mercaptan, t-dodecyl mercaptan, n-butyl mercaptan, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, (CH3O) 3Si-SS-
Si (OCH3) 3, (CH3O) 3Si-S8-Si
A vinyl copolymer (A) obtained by using a chain transfer agent such as (OCH3) 3 alone or in combination of two or more.
May be adjusted. In particular, for example, when a chain transfer agent having an alkoxysilyl group in a molecule such as γ-mercaptopropyltrimethoxysilane is used,
A reactive silyl group can be introduced into the terminal of the vinyl copolymer (A). The amount of the chain transfer agent used is 0.05 to 10% of the total amount of the polymerization components used, preferably 0.1 to 10%.
It is preferably about 8%.

In the present invention, the organometallic compound (B)
By blending the composition comprising the component and the weak solvent component (C) with the component (A), the composition has excellent curability over a low to high temperature range, and has a sufficient pot life in operation. Can be. The organometallic compound (B)
Typical examples thereof include an organotin compound and an aluminum chelate. Dioctyltin bis (2-ethylhexyl maleate), dioctyltin oxide or condensate of dibutyltin oxide and silicate, dibutyltin dioctoate, dibutyltin dilaurate, dibutyltin distearate, dibutyltin diacetylacetate Nath, dibutyltin bis (ethylmaleate), dibutyltinbis (butylmaleate), dibutyltinbis (2-ethylhexylmale)
G), dibutyltin bis (oleyl maleate), stanna octoate, tin stearate, and di-n-butyltin rallate oxide. Examples of the tin compound having an S atom in the molecule include dibutyltin bisisononyl-3-mercaptopropionate, dioctyltin bisisononyl-3-mercaptopropionate, octylbutyltin bisisononyl-3-mercaptopropionate, Examples of the organotin compound include dibutyltin bisisooctylthioglucolate, dioctyltin bisisooctylthioglucolate, octylbutyltin bisisooctylthioglucolate, and the like.

The aluminum chelate compound includes ethyl acetoacetate aluminum diisopropylate,
Aluminum tris (acetyl acetate), aluminum tris (ethyl acetoacetate), aluminum monoacetyl acetonate bis (ethyl aceto acetate), alkyl acetyl acetate aluminum diisopropylate and the like can be mentioned.

The organometallic compound (B) may be used alone, or two or more different types or the same type may be used in combination.

The curing catalyst (B) is used in an amount of 0.1 to 20 parts, preferably 0.2 to 20 parts, per 100 parts of the component (A).
The amount is preferably 13 parts, more preferably 0.5 to 10 parts. When the amount of (B) used is less than 0.1, the curability of the obtained coating film is insufficient and the weather resistance is not exhibited. If the amount exceeds 20 parts, the appearance of the coating film formed using the composition tends to decrease such as the surface gloss, which is not preferable.

The weak solvent (C) is not particularly limited.
Also, there is no particular limitation on the amount used. here,
Weak solvents are Class 3 organic solvents and third
It is a solvent corresponding to the seed organic solvent. Preferably, those containing an aliphatic hydrocarbon as the component (C) are preferable. Such examples include those containing high boiling hydrocarbons, such as terpenes and mineral spirits.

In the present invention, together with the above-mentioned vinyl copolymer (A), the compound represented by the general formula (2)

[0048]

Embedded image (Wherein R ⁴ is a monovalent hydrocarbon group selected from an alkyl group having 1 to 10 carbon atoms, an aryl group and an aralkyl group;
R ⁵ is a monovalent hydrocarbon group selected from an alkyl group, an aryl group and an aralkyl group having 1 to 10 carbon atoms, and b represents 0 or 1) and / or a partial hydrolytic condensation thereof. The compound (D) is used in an amount of 2 to 70 parts by weight (hereinafter, also referred to as silicon compounds (D)).
By using the component (D), the stain resistance of the coating film formed from the composition of the present invention can be improved, and the adhesion between the coating film and the object to be coated can be improved. A composition obtained by mixing the silicon compound (D) with the vinyl copolymer (A) becomes a composition having room-temperature curability, and a coating film formed using the composition has excellent stain resistance. .

In the general formula (2), R ⁴ has 1 to 10 carbon atoms, preferably, for example, methyl group, ethyl group, n
-Propyl group, i-propyl group, n-butyl group, alkyl group having 1 to 4 carbon atoms such as i-butyl group, aryl group,
It is preferably a monovalent hydrocarbon group selected from an aryl group having 6 to 9 carbon atoms such as a phenyl group and an aralkyl group, and preferably an aralkyl group having 7 to 9 carbon atoms such as a benzyl group.

When the alkyl group has more than 10 carbon atoms, the reactivity of the silicon compound (D) decreases. R ⁴ is the alkyl group, the aryl group,
Even in the case other than the aralkyl group, the reactivity decreases.

[0051] Further, in the general formula (2), R ⁵ is 1 to 10 carbon atoms, preferably also having 1 to 4 carbon atoms and R ⁴
An aralkyl group, an aryl group, preferably an aryl group having 6 to 9 carbon atoms and an aralkyl group similar to R ^4, and preferably a monovalent hydrocarbon selected from an aralkyl group having 7 to 9 carbon atoms similar to R 3. is there.

In the general formula (2), (R ⁴ O) 4
-B is selected so that 4-b is 3 or more, that is, b is 0 or 1, but from the viewpoint that the curability of the coating film formed from the composition of the present invention is improved, Preferably, b is 0.

(R ⁴ O) 4- existing in the general formula (2)
When the number of b is 2 or more, R ⁴ contained in 2 or more may be the same or different.

Specific examples of the silicon compound include tetraalkyl silicates such as tetramethyl silicate, tetraethyl silicate, ESI28, tetra n-propyl silicate, tetra i-propyl silicate, tetra n-butyl silicate and tetra i-butyl silicate. Methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, octadecyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, methyltrisec-octyloxysilane, methyltriphenoxysilane, methyltrimethoxysilane Examples include silane coupling agents such as isopropoxysilane and methyltributoxysilane.

Specific examples of the partially hydrolyzed condensate (D) of the silicon compound include those obtained by adding water to the above tetraalkylsilicate or trialkoxysilane and condensing it by an ordinary method. For example, MSI51, ESI40, HAS-1, HAS-
10 (all manufactured by Colcoat Co., Ltd.), MS51, MS5
6, MS51B15, MS56S (Mitsubishi Chemical Corporation), silicate 45, silicate 48, FR-
3 (above, manufactured by Tama Chemical Co., Ltd.) or a partially hydrolyzed condensate of tetraalkyl silicate, for example, AFP-
1 (manufactured by Shin-Etsu Chemical Co., Ltd.) and the like.

Among the silicon compounds (D),
Since the compatibility with the vinyl copolymer (A) and the curability of the obtained composition of the present invention are good and the hardness of the coating film formed by using the composition is excellent, the adhesion of contaminants can be prevented. MSI51, MS51, MS
56, MS51B15, MS56S (partially hydrolyzed condensate of tetramethoxysilane), ESI40, silicate 45, silicate 48 (partially hydrolyzed condensate of tetraethoxysilane), FR-3 (co-deposition of tetramethoxysilane and tetraethoxysilane) It is preferable to use a partially hydrolyzed condensate of a tetraalkyl silicate such as a partially hydrolyzed condensate.

The amount of the partially hydrolyzed condensate (D) of the silicon compound is 2 to 100 parts by weight of the component (A).
70 parts by weight, preferably 2 to 50 parts by weight, more preferably 2 to 30 parts by weight.

When the amount of the partially hydrolyzed condensate (D) of the silicon compound is less than 2 parts by weight per 100 parts by weight of the component (A), the resulting composition is used. The effect of improving the curability and stain resistance of the formed coating film becomes insufficient, and if it exceeds 70 parts, the appearance such as the surface gloss of the coating film is reduced or cracks are generated. Become.

Among the partially hydrolyzed condensates (D) of the silicon compound, MS56 and MS56 having a high degree of condensation are preferred.
S, silicate 45, silicate 48, and the like are preferable in that the contact angle is reduced from the beginning.

In the present invention, a silane coupling agent (E) can be blended. A specific example is γ
-Aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, 2-aminoethylaminopropyltrimethoxysilane, 2-aminoethylaminopropyltriethoxysilane, N-phenylpropyltrimethoxysilane, N-phenylpropyltriethoxysilane, γ A 2.2: 1 (molar ratio) reaction product of glycidylpropyloxytrimethoxysilane and 2-aminoethylaminopropyltrimethoxysilane, Epicoat 828
(Made by Yuka Shell Epoxy Co., Ltd.) and γ-aminopropyltriethoxysilane in a ratio of 1: 2 (molar ratio). When the component (E) is blended, it is possible to impart adhesion to the base with an epoxy intermediate coating agent or the like.

Specific examples of the hydrolyzable ester compound (F) include, for example, methyl orthoformate, ethyl orthoformate, methyl orthoacetate, ethyl orthoacetate, trimethyl orthopropionate, triethyl orthopropionate, trimethyl orthoisopropionate. A hydrolysable ester compound such as triethyl orthoisopropionate, trimethyl orthobutyrate, triethyl orthobutyrate, trimethyl orthoisobutyrate, triethyl orthoisobutyrate; or dimethoxymethane, 1,1-dimethoxyethane,
1,1-dimethoxypropane, 1,1-dimethoxybutane; or ethyl silicate (tetramethoxysilane), methyl silicate (tetramethoxysilane), methyltrimethoxysilane, and the like. Of these, methyl orthoacetate is preferred from the viewpoint of the dehydration effect.
These may be used alone or in combination of two or more. The component (F) has the effect of a dehydrating agent.

Examples of the mercapto group-containing hydrocarbon and / or mercaptosilane (G) include n-dodecylmercaptan, t-dodecylmercaptan, n-butylmercaptan, γ-mercaptopropyltrimethoxysilane and γ-mercaptopropyltriethoxysilane. Silane, α-
Mercaptomethylpentamethyldisiloxane, γ-mercaptopropylpentamethyldisiloxane, γ-mercaptopropyltris (trimethylsiloxy) silane, (C
_{H 3 O) 3 Si-S} -S-Si (OCH 3) 3, (CH
₃ O) ₃ Si—S ₈ —Si (OCH ₃ ) _{3 and the} like. From the viewpoint of availability and storage stability when blended with an organometallic compound, γ-mercaptopropyltrimethoxysilane and γ-mercaptopropyltriethoxysilane is preferred. These can be used alone or in combination of two or more. The component (G) can extend the pot life, but it can be added to the composition comprising the components (B) and (C) or to the vinyl copolymer (A). Good.

The amount of the silane coupling agent (E) to be used is 0.1 to 300 parts by weight, preferably 0.2 to 100 parts by weight, more preferably 0.5 to 0.5 parts by weight based on the component (A).
５０50 parts by weight. If the amount of (E) used is less than 0.1 part, the adhesion to the undercoat, intermediate coat and undercoat is insufficient. On the other hand, when the amount exceeds 300 parts by weight, defects such as poor coating film appearance and cracks are caused.

The hydrolyzable ester compound (F) may be added to the component before the polymerization of the vinyl copolymer (A), or may be added during the polymerization of (A).
It may be added at the time of mixing the obtained vinyl copolymer (A) with other components, and there is no particular limitation.

The blending amount of the hydrolyzable ester compound (F) is not particularly limited, but is usually based on 100 parts by weight of the resin solid content of the vinyl copolymer (A) or the partially hydrolyzed condensate of the silicon compound. The total amount of the dehydrating agent and the alkyl alcohol is about 0.5 to 20 parts by weight, preferably 2-1.
It is preferably about 0 parts by weight.

The mercapto group-containing hydrocarbon and / or mercaptosilane (G) is used in an amount of 0 to 20 parts by weight based on (A). Preferably, 0.1 to 1
0 parts by weight, more preferably 0.2 to 5 parts by weight.

In addition, additives such as a diluent, an ultraviolet absorber, a light stabilizer, an anti-sagging agent and a leveling agent; fibrous materials such as nitrocellulose and cellulose acetate butyrate; epoxy resins, melamine resins, Resins such as vinyl chloride resin, fluororesin, chlorinated polypropylene, chlorinated rubber, polyvinyl butyral, and polysiloxane may be appropriately added.

The curable resin composition for paints of the present invention is prepared by adding a composition comprising an organometallic compound (B) and a weak solvent (C) to a vinyl copolymer (A) using, for example, a stirring group. It can be obtained by stirring and mixing to obtain a uniform composition.

The curable resin composition for paints of the present invention includes, for example, titanium oxide, ultramarine,
Inorganic pigments such as navy blue, zinc white, red iron, lead white, carbon black, transparent iron oxide, aluminum powder, etc., azo pigments, triphenylmethane pigments, quinoline pigments,
Pigments such as organic pigments such as anthraquinone pigments and phthalocyanine pigments; diluents, ultraviolet absorbers, light stabilizers,
Additives such as anti-sagging agents and leveling agents; cellulose such as nitrocellulose and cellulose acetate butyrate;
Epoxy resin, melamine resin, vinyl chloride resin, fluorine resin, chlorinated polypropylene, chlorinated rubber, polyvinyl butyral, polysiloxane, and other resins may be appropriately added.
The curable resin composition for paint of the present invention is, for example, dipping,
It is applied to an object to be coated by an ordinary method such as spraying, application using a brush or the like, and is usually cured at room temperature as it is or by baking at about 30 degrees or more.

The curable resin composition for paints of the present invention can be used for topcoating of, for example, metals, ceramics, glass, cement, ceramic moldings, plastics, woods, papers, fibers, buildings, home appliances, industrial equipment and the like. It is suitably used as a coating material for use. Next, the curable resin composition for paints of the present invention will be described in more detail based on Examples, but the present invention is not limited to only these Examples.

Production Example 1 (Production of Acrylic Copolymer (A)) 40 parts of xylene was charged into a reaction vessel equipped with a stirrer, thermometer, reflux condenser, nitrogen gas inlet tube and dropping funnel.
The temperature was raised to 110 ° C. while introducing nitrogen gas. after that,
γ-methacryloxypropyltrimethoxysilane 7.9
Part, methyl methacrylate 34.6 parts, i-butyl methacrylate 17.0 parts, lauryl methacrylate 40.
A mixture consisting of 5 parts, 18.0 parts of toluene, and 1.5 parts of 2,2'-azobisisobutyronitrile was dropped at a constant rate over 5 hours from a dropping funnel.

After completion of the dropwise addition, 0.2 parts of 2,2′-azoisobutyronitrile and 24.0 parts of toluene were added dropwise at a constant speed over 1 hour, and the mixture was aged at 110 ° C. for 2 hours and cooled. Xylene is added to the resin solution to make the resin solids concentration 5
0% of an acrylic copolymer (A) -1 was obtained. The number average molecular weight of the obtained acrylic copolymer (A) -1 is 100.
00.

Production Example 2 (Production of Acrylic Copolymer (A)) In Production Example 1, 13.0 parts of γ-methacryloxypropyltrimethoxysilane, methyl methacrylate 55.
7 parts, n-butyl acrylate 30.3 parts, n-methylol acrylamide 1.0 part, toluene 18.0 parts, methanol 1.4 parts and 2,2'-azobisisobutyronitrile 0.9 parts A vinyl copolymer (A) having a resin solids concentration of 50% in the same manner as in Production Example 1 except that
-2 was obtained. The number average molecular weight of the obtained vinyl copolymer (A) -2 was 15,000.

Production Example 3 (Production of Acrylic Copolymer (A)) In Production Example 1, xylene and toluene were all replaced with Naphtha No. Production Example 1 except changing to 6 (Exxon Chemical)
In the same manner as in the above, a vinyl copolymer (A) -3 having a resin solid content of 50% was obtained. The number average molecular weight of the obtained vinyl copolymer (A) -3 was 10,000. Example 1 With respect to 100 parts of the vinyl copolymer (A) component, 5 parts of dibutyltin bisbutylmalate was used as the organometallic compound (B) -1 and Naphtha No. 5 was used as the weak solvent (C) -1. 6 to 4
1.5 parts, as a silane coupling agent (E) -1, 8 parts of a reaction product of aminoethylaminopropyltrimethoxysilane and γ-glycidoxypropyltrimethoxysilane in a ratio of 1: 2.2 (molar ratio), mercaptan Compound (G) -1
Γ-mercaptopropyltrimethoxysilane as 4
, And diluted with 41.5 parts of i-propyl alcohol to prepare a composition. Next, the silicone compound (D) and the hydrolyzable ester compound (F) were added to 100 parts of the resin solid content of the vinyl copolymer (A) obtained in Production Example 1.
And the composition were prepared at the compounding ratio shown in Table-2. Further, a thinner was added and the mixture was stirred for 5 minutes using a stirrer to obtain a composition having a solid content of 45%. Examples 2 to 9 In the same manner as in Example 1, according to the formulations shown in Tables 1 and 2, a composition having a solid content of 45% was obtained. Neo goose # 2300NT-H on aluminum plate (A5052P)
B (manufactured by Shinto Paint Co., Ltd.), dried at 23 ° C. for 1 day, and further coated with the coating composition obtained in Example 1 by air spray so that the dry film thickness became 30 μm. 5 ℃
For 7 days to form a coating film.

Immediately after drying the obtained coating film, appearance, low-temperature curability, contact angle, adhesion, stain resistance, weather resistance and pot life were evaluated by the following methods. Appearance The gloss and sharpness were visually evaluated comprehensively. ○ indicates good, Δ indicates normal, and × indicates poor. Curability (Gel Fraction) The paint obtained in Table 2 was applied on a polyethylene sheet and dried at 5 ° C. for 3 days and 7 days to obtain a free clear film having a thickness of about 30 μm and a thickness of about 50 μm. × 50
It was cut into a size of mm, wrapped in a 200 mesh stainless steel wire mesh (W0) that had been precisely weighed in advance, and weighed precisely (W1).
Thereafter, the sample is immersed in acetone for 24 hours to perform extraction, and then dried and weighed (W2). Formula: gel fraction (%) = ｛((W2) − (W0)) / ((W1)
) − (W0))｝ × 100 to determine the gel fraction (%). Contact angle The static contact angle of the coating film surface with water was measured with a contact angle measuring device (model CA-S150, manufactured by Kyowa Interface Science Co., Ltd.). Adhesion The primary adhesion was evaluated by measuring the cross-cut adhesion of the coating film immediately after formation according to JIS K5400. (Evaluation criteria) 10: 100/100 8: 80/100 6: 60/100 4: 40/100 2: 20/100 0: 0/100 Stain resistance L * a * b * color system at the beginning of exposure The lightness represented was measured with a colorimeter (CR-300, manufactured by Minolta Co., Ltd.), and an outdoor exposure of 30 ° on the south side was performed in Settsu City, Osaka Prefecture for 3 months. The lightness difference (ΔL) before and after exposure was determined and used as a measure of contamination. The smaller the absolute value, the better the stain resistance, and the larger the absolute value, the more dirty. Weather resistance (gloss retention) Using a sunshine weatherometer, the gloss of the coating surface immediately after formation and the gloss of the coating surface after 2,000 hours have been measured, and the gloss retention (%) after 2,000 hours has elapsed. I asked. Pot life The paint obtained in Table 2 was left in an open system at a temperature of 23 ° C. and a constant temperature of 55% RH, and the time until gelation was examined. In addition,
The abbreviations in Tables 1 and 2 indicate the following. Vinyl-based copolymer (A) (A) -1; Vinyl-based copolymer (A) obtained in Production Example 1 (A) -2; Vinyl-based copolymer (A) obtained in Production Example 2 (A) -3: Vinyl copolymer obtained in Production Example 3 (A) Organometallic compound (B) (B) -1: Dibutyltin bisbutylmaleate (B) -2: Dibutyltin bisoleylmale G. Weak solvent (C) (C) -1; 6 (manufactured by Exxon Chemical Co., Ltd.) (C) -2; P-20 (manufactured by Japan Energy Co., Ltd.) (C) -3; Exol D40 (Exxon Chemical Co., Ltd.)
(C) -4; Isobar G (manufactured by Exxon Chemical Co., Ltd.) (C) -5; Xylene silicate compound (D) (D) -1; Ethyl silicate 48 (Corcoto Co., Ltd.)
(D) -2; MS56S (manufactured by Mitsubishi Chemical Corporation) (D) -3; FR-3 (manufactured by Tama Chemical Co., Ltd.) Silane coupling agent (E) (E) -1; aminoethylamino 1: 2.2 (molar ratio) reaction product of propyltrimethoxysilane and γ-glycidoxypropyltrimethoxysilane (E) -2; bisphenol A type bifunctional epoxy compound (Epicoat 828; oiled shell) Epoxy Corporation)) and γ-aminopropyltriethoxysilane in a ratio of 1: 2 (molar ratio) (E) -3; γ-aminopropyltriethoxysilane hydrolyzable ester compound (F) (F) -1; methyl orthoacetate (F) -2; methyl orthoformate Mercapto group-containing hydrocarbon and / or mercaptosilane (G) (G) -1; γ-mercaptopropyltrimethoxysilane (G) -2; n -Dode Mercaptan

[0076]

[Table 1]

[0077]

[Table 2]

[0078]

[Table 3] From the results shown in Table 3, it can be seen that the resin compositions obtained in Examples 1 to 9 have excellent curability even at a low temperature and have a very long pot life. Further, the coating film formed from the resin composition has a good surface condition,
Further, it can be seen that when the silicon compound (D) is compounded, the contact angle on the surface is small and excellent contamination resistance is exhibited.

[0079]

The curable resin composition for paints of the present invention has excellent curability even at a low temperature, has a sufficiently long pot life, and the coating film formed from the resin composition has a surface condition. It is good and has excellent weather resistance, and has a small contact angle and excellent contamination resistance by blending a silicon compound.

[0080]

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Naoto Ando 3-130-1 Nozoe, Harima-cho, Kako-gun, Hyogo F-term (reference) 4J038 CA001 CB081 CC001 CD011 CE051 CF011 CG001 CG141 CG161 CH001 CH031 CH041 CH051 CH071 CH081 CH191 CH201 CH221 CH251 CJ18 CK021 CL001 DB211 GA02 GA03 GA06 GA08 GA09 GA10 GA13 GA14 GA15 JA02 JA03 JA19 JA32 JA55 JA56 JC02 JC34 JC35 JC36 JC38 JC39 KA03 KA04 MA07 MA09 NA03 NA05 NA26 PA18

Claims (11)

[Claims] 1. A curing method for a topcoat paint, comprising mixing a composition comprising an organometallic compound (B) and a weak solvent (C) with a vinyl copolymer (A) having an alkoxysilyl group. Composition. 2. The method according to claim 1, wherein the vinyl copolymer (A) is a polymer obtained by polymerizing a monomer unit having a reactive silyl group represented by the following general formula (1). The curable resin composition for an overcoat paint according to the above. Embedded image (In the formula, R ¹ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, when there are a plurality may .R ² be different even if the same is a hydrogen atom, C 1 -C ~ 1
Represents an alkyl group having 0, an aryl group having 6 to 10 carbon atoms, or an aralkyl group having 7 to 10 carbon atoms. When a plurality of aralkyl groups are present, they may be the same or different. a
Represents an integer of 0 to 2. ) 3. The vinyl copolymer (A) is obtained by copolymerizing 1 to 90 parts of a monomer unit having a reactive silyl group represented by the general formula (1) in the molecule. The curable resin composition for a topcoat paint according to claim 1, which is a polymer. 4. The method according to claim 1, wherein the organometallic compound (B) is a component (A).
The curable resin composition for a topcoat paint according to any one of claims 1 to 3, wherein the curable resin composition is contained in an amount of 0.1 to 20 parts by weight based on 00 parts by weight. 5. The curable resin composition for a top coat according to claim 1, wherein the organometallic compound (B) is an organotin compound. 6. The curable resin composition for a topcoat paint according to claim 1, wherein the weak solvent (C) component contains an aliphatic hydrocarbon. 7. The composition has the following general formula (2): (Wherein R ⁴ is a monovalent hydrocarbon group selected from an alkyl group having 1 to 10 carbon atoms, an aryl group and an aralkyl group;
R ⁵ is a monovalent hydrocarbon group selected from an alkyl group, an aryl group and an aralkyl group having 1 to 10 carbon atoms, and b represents 0 or 1) and / or a partial hydrolytic condensation thereof. The curable resin composition for a topcoat paint according to any one of claims 1 to 6, comprising 2 to 70 parts by weight of the product (D) based on 100 parts by weight of the component (A). 8. A silane coupling agent (E) comprising at least one or two or more compounds selected from the group consisting of aminosilanes, epoxysilanes and their reaction products is added to the composition (A). The curable resin composition for a topcoat paint according to any one of claims 1 to 7, wherein the curable resin composition is contained in an amount of 0.1 to 300 parts by weight based on 100 parts by weight. 9. The composition according to claim 1, wherein the hydrolyzable ester compound (F) is used in an amount of 0.1 to 1 with respect to 100 parts by weight of (A).
The curable resin composition for a topcoat paint according to any one of claims 1 to 8, wherein the curable resin composition is contained in an amount of 50 parts by weight. 10. The curable resin composition for a topcoat paint according to claim 1, wherein a mercapto group-containing hydrocarbon and / or mercaptosilane (G) is blended with the composition. object. 11. A coated article obtained by applying the composition for a top coating composition according to any one of claims 1 to 10.