JP2658047B2 - Resin composition for paint - Google Patents

Description

The present invention relates to a novel and useful coating resin composition, and more particularly, to a resin composition having at least one unsaturated double bond and at least one silyl ester group in one molecule. A vinyl-based polymer obtained by polymerizing a vinyl-based monomer having a vinyl-based monomer and another vinyl-based monomer copolymerizable with the monomer has a curing property that is reactive with a carboxyl group generated by the polymer. The present invention relates to a resin composition for coatings, which comprises an agent (crosslinking agent) and, if desired, a dissociation promoting catalyst and / or a water binder.

2. Description of the Related Art In recent years, plasticization of outer plates, parts, and the like has been rapidly progressing in the automobile industry and the home appliance industry. When the material is a steel plate, a baking one-pack type paint using an aminoplast-based curing agent is usually used as a paint resin system to be used. However, when the material is made of plastic, there is a case where the heat resistance temperature of the material is low, and it is not appropriate to use a normal baking one-pack type paint for plastic. Therefore, room temperature-curable and low-temperature curable paints have been studied or partially used for plastics. Examples of these paint-based resins include a combination of a polyol type resin and an isocyanate prepolymer, a combination of an acrylic resin having a tertiary amino group and a polyfunctional epoxy resin, and a curing system using aminoplast using a low-temperature curing catalyst. However, among such paint systems, the polyol type resin-isocyanate prepolymer system and the tertiary amino group-epoxy resin cured system are both two-pack types and have major drawbacks in workability such as pot life.

On the other hand, an aminoplast system using a low-temperature curing catalyst is a one-pack type as a form, but the functional groups involved in the reaction are not blocked, it is rich in activity, and its storage stability for a long time is extremely poor. It has drawbacks and cannot be cured at temperatures around room temperature.

In addition, if an isocyanate prepolymer obtained by separately blocking an isocyanate prepolymer with an appropriate blocking agent is used, a one-pack type polyol-type resin-isocyanate prepolymer curing system is obtained, but at present, the dissociation temperature of the blocking agent is high, and the room temperature or low temperature is used. It is hard to say that it is a curable resin type.
As mentioned above, in the industry, from the viewpoint of coating workability, and from the viewpoint of material conversion and energy saving, room temperature or low temperature curable resin coatings that are one-pack type and have excellent long-term storage stability, various physical properties, weather resistance, etc. It is the present situation that urgent development is required.

However, the present inventors have conducted intensive studies to obtain a vinyl-based polymer coating resin that meets the above-mentioned various requirements, and as a result, have found that a vinyl-based monomer having an unsaturated double bond and a silyl ester group is used. The present inventors have found that a composition comprising a system polymer and a crosslinking agent can satisfy the above-mentioned required performance, and have completed the present invention.

That is, the present invention relates to (A) 1 to 100% by weight of a vinyl monomer having at least one unsaturated double bond and a silyl ester group in one molecule, and (B) other than (A) A vinyl copolymer (I) comprising 99 to 0% by weight of a copolymerizable vinyl monomer is added to the polymer (I).
The present invention provides a coating resin composition comprising a curing agent (II) having a reactivity with a carboxyl group generated from the composition.

Here, the vinyl-based monomer (A) is a vinyl-based monomer containing at least one unsaturated double bond and a silyl ester group bonded to a carbon atom represented by the following formula in one molecule. It is a monomer.

(However, R ₁ , R ₂ and R _{3 each} represent H, an alkyl group or an aryl group, and may be the same or different.) The vinyl monomer (A) is, for example, hydrochloric acid such as triethylamine or pyridine. Vinyl monomers containing a carboxyl group in the presence of a scavenger, such as acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid or fumaric acid; monoalkyl maleate, monoalkyl fumarate or itaconic acid A monoalkyl ester; or a carboxyl group-containing vinyl monomer such as an adduct of a vinyl monomer having a hydroxyl group with an acid anhydride such as succinic anhydride or trimellitic anhydride; and a trialkyl chloro such as triethylchlorosilane. Dialkylchlorosilanes such as silane and diethylchlorosilane and triaryl A vinyl monomer obtained by reacting with a halogenated silanization, such as a chlorosilane compound such as chlorosilane or a trialkylbromosilane such as trimethylbromosilane or a bromosilane compound such as triarylbromosilane, and further, for example, The acid chloride of the carboxyl group-containing vinyl monomer and a silanol compound such as trialkylsilanol such as triethylsilanol or diethylsilanol or a silanol compound such as triarylsilanol are reacted in the presence of triethylamine or pyridine, Carboxyl group-containing vinyl monomers such as carboxylic acid esters and trialkylchlorosilanes such as trimethylchlorosilane and dialkylchlorosilanes such as diethylchlorosilane and triarylchlorosilanes It is obtained by reacting chlorosilane in the presence of sodium iodide, but is not limited thereto.

On the other hand, typical other monomers (B) having copolymerizability with the vinyl monomer include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, -Propyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, t-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, cyclohexyl (meth) acrylate (Meth) acrylic esters such as benzyl (meth) acrylate, dimethylaminoethyl (meth) acrylate and diethylaminoethyl (meth) acrylate; dimethyl malate, dibutyl malate, dimethyl fumarate, dibutyl fumarate, dibutyl itaconate Unsaturated two like Dialkyl esters Motosan; such a cyano group-containing monomers such acrylonitrile; vinyl acetate, vinyl benzoate, "VeoVa" (Netherlands Shell Company) such as vinyl esters; "Viscoat 8F, 8F
M, 3F or 3FM] [fluorinated (meth) acrylic monomers manufactured by Osaka Organic Chemical Co., Ltd.], perfluorocyclohexyl (meth) acrylate, di-perfluorocyclohexyl fumarate or N-isopropyl perfluorooctanesulfonamidoethyl Fluoroalkyl or perfluoroalkyl group-containing monomers such as (meth) acrylate; halogenated olefins such as vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride, and chlorotrifluoroethylene; styrene, vinyltoluene, and aromatic vinyl monomers such as α-methylstyrene and pt-butylstyrene.

These vinyl monomers (A) and (B) can be used alone or as a mixture of two or more, depending on the desired coating film performance. The amount of the vinyl monomer (A) used is 1 to 100% by weight, preferably 5 to 90% by weight,
If the amount is less than 1% by weight, the effect of the monomer cannot be expected.

In order to prepare the vinyl polymer (I) from such monomers, any of conventionally known polymerization methods such as a solution polymerization method and a non-aqueous dispersion polymerization method can be applied, but the simplest method is solution radical polymerization. It is. The number average molecular weight of the vinyl polymer (I) is preferably in the range of 1,000 to 50,000. If the number average molecular weight is less than 1000, desired performance cannot be obtained, while 5000
Exceeding 0 adversely affects workability.

Typical solvents used herein include hydrocarbon solvents such as toluene, xylene, cyclohexane, n-hexane and octane; methyl acetate, ethyl acetate,
Ester solvents such as n-butyl acetate and amyl acetate; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl amyl ketone, and cyclohexane; and of course, any mixture thereof can also be used.

Solution radical polymerization is carried out by a conventional method using the solvent and various radical polymerization initiators such as an azo type represented by azobisisobutyronitrile or a peroxide type represented by benzoic peroxide. In this case, if necessary, lauryl mercaptan, octyl mercaptan, as a molecular weight regulator, if necessary.
A chain transfer agent such as 2-mercaptoethanol, octyl thioglycolate, 3-mercaptopropionic acid or α-methylstyrene dimer can also be used.

Next, examples of those used as a curing agent (II) having reactivity with a carboxyl group generated from the polymer (I) include alkoxides or chelate compounds of polyvalent metals. Typical examples thereof include alkoxides or chelating compounds such as aluminum, titanium, zirconium, cobalt, zinc, copper, lead, magnesium, vanadium, iron or nickel, but they have curability, low toxicity and low toxicity. Among these, aluminum, titanium, and zirconium alkoxides or chelate compounds are particularly preferable from the viewpoint of coloring property and the like. Specific examples of such metal alcoholates include aluminum isopropylate, aluminum-n-butylate,
Aluminum-sec-butylate, aluminum isobutyrate, aluminum-t-butylate, tetra-n
-Propyl titanate, tetra-i-propyl titanate, tetra-n-butyl titanate, tetra-n-butyl titanate dimer, tetra-n-butyl titanate tetramer, tetra-sec-butyl titanate, tetramethyl zirconate, tetraethyl zirconate , Tetra-i-propyl zirconate, tetra-n-butyl zirconate, tetra-i-butyl zirconate and the like.

On the other hand, a polyvalent metal chelate compound can be prepared by reacting the above-mentioned alcoholates with a chelating agent. Specific examples of such a chelating agent include monoethanolamine, diethanolamine, triethanolamine, dimethylaminoethanol. Such as alkanolamines, methyl acetoacetate, acetoacetates such as ethyl acetoacetate, acetyl-acetone, β-diketones such as benzoylacetone, dimethyl malonate, malonates such as diethyl malonate, methyl salicylate, Salicylic acid esters such as ethyl salicylate, ethylene glycol, 1,3-propanediol, 1,3-butanediol, glycols such as octylene glycol, lactic acid, oxyacids such as tartaric acid and esters thereof, and Diacetone alcohol,
Catechol and the like.

Specific examples of the complex compound obtained from the alcoholates and the chelating agent include aluminum bis (ethylacetoacetate) monoisopropylate, aluminum tris (ethylacetoacetate), and aluminum bis (ethylacetoacetate) monoacetoacetonate. Di-i-propoxy-bis (acetylacetone) titanate, di-i-propoxy-bis (ethylacetoacetate) titanate, di-n-butoxy-bis (acetylacetone) titanate, di-n-butoxy-
Bis (triethanolamine) titanate, tetraoctylene glycol titanate, n-butoxy-tris (acetylacetone) zirconate, n-butoxy-tris (ethylacetoacetate) zirconate, tetrakis (acetylacetone) zirconate, tetrakis (ethylacetoacetate) zirconate, Tris (acetylacetone) monoethyl acetoacetate zirconate, bis (acetylacetone) bis (ethylacetoacetate) zirconate and the like can be mentioned.

The amount of the curing agent (II) to be added to the vinyl polymer (I) is in the range of 0.01 to 10% by weight, preferably 0.05 to 5% by weight, based on the vinyl polymer (I). It is preferable to set. If the amount used is less than 0.01% by weight, the curability is inferior. If the amount exceeds 10% by weight, the cured product becomes extremely brittle, which is not preferable.

The composition of the present invention may contain a dissociation accelerating catalyst for dissociating the silane compound bonded to the carboxyl group with moisture in the air to form a carboxylic acid and a silanol compound. When the composition of the present invention is cured in a temperature range from room temperature to less than 60 ° C., it is preferable to use a catalyst. However, it does not impede its use. Examples of the catalyst include acidic catalysts such as phosphoric acid, phosphoric acid ester, phosphite, p-toluenesulfonic acid and its amine salt, benzoic acid, trichloroacetic acid, trifluoroacetic acid, naphthalene disulfonic acid and its amine salt. , Ethylenediamine, N-β-aminoethyl-
amines such as γ-aminopropyltrimethoxysilane, butylamine, dibutylamine, t-butylamine, hexylamine, triethylamine, potassium hydroxide,
Alkaline catalysts such as lithium hydroxide and sodium hydroxide,
Alkyl titanates, octylates, metal salts of carboxylic acids such as dibutyltin dilaurate, and lead octylate, sulfides such as monobutyltin sulfide, dioctyltin mercaptite, mercaptide-type organic tin compounds, tetraethylammonium fluorite, fluoride Compounds that generate fluorine ions such as cesium are effective. The amount of these catalysts used is 0.01 to 10 based on the vinyl polymer (I).
% By weight, preferably 0.005 to 8% by weight.

Since the composition of the present invention does not generate a carboxyl group that can react with the curing agent unless exposed to the atmosphere, a one-pack type and highly stable coating composition can be obtained from the composition of the present invention. However, to ensure long-term storage stability,
What is necessary is just to capture a small amount of water that enters for some reason. That is, long-term stability is ensured by adding a water binder reactive with moisture. This water binder may be used by being mixed in advance at the initial stage when producing the vinyl polymer (I). Examples of the water binding agent having reactivity with water include trialkyl orthoformates such as trimethyl orthoformate, triethyl orthoformate and tributyl orthoformate; and trialkyl orthoacetates such as trimethyl orthoacetate, triethyl orthoacetate and tributyl orthoacetate. Trialkyl orthoborates such as tributyl orthoborate and triethyl orthoborate; tetra (substituted) such as tetramethylsilicate, tetraethylsilicate, tetrabutylsilicate, tetra (2-methoxyethyl) silicate or tetra (2-chloroethyl) silicate Alkyl silicates alone; the same active substances as the above tetra (substituted) alkyl silicates such as tetraphenyl silicate and tetrabenzyl silicate (hereinafter abbreviated as the same effective single units); Silicate dimer, trimer, tetramer, hexamer “Ethyl silicate 40” (product of Colcoat Co., Ltd., tetraethyl silicate tetramer, pentamer, hexamer mixture), and the above tetra (substituted) alkyl silicates alone or the silicate Ester compounds such as condensates of the same simple substance, phenyl isocyanate, p-chlorophenyl isocyanate, benzenesulfonyl isocyanate, p
-Triene sulfonyl isocyanate, isocyanate ethyl methacrylate (manufactured by Dow Chemical
Compounds having an isocyanate group, such as an O group-containing monomer).

The amount used is 0.1 to the vinyl polymer (I).
-30% by weight, preferably 0.5-20% by weight.

The composition of the present invention thus obtained can be used as a clear paint as it is, and can also be used as an enamel paint by mixing a pigment. The composition of the present invention may contain various conventional additives such as a leveling agent, an ultraviolet absorber, and a pigment dispersant, if necessary.

Further, known and commonly used cellulosic compounds, plastic or polyester resins, and the like can also be used.

As a coating method, a common method such as brush coating, spray coating or roll coating can be adopted, and as a curing method, crosslinking with the copolymer component constituting the composition of the present invention in a wide range from room temperature drying to heating drying. Optimal curing conditions can be designed according to the combination with the agent component.

The composition of the present invention thus obtained is a plastic,
It can be widely used for metals, wood, building materials, inorganic materials and the like. In particular, the effect is remarkable in the field where storage stability is required for a one-pack type room temperature / low temperature curing type.

Next, the present invention will be specifically described with reference examples, production examples, examples, and comparative examples. In the following, all parts are by weight unless otherwise specified.

Reference Example 1 [Preparation of vinyl monomer (A)] In a four-necked flask equipped with a thermometer, a reflux condenser, a stirrer, and a nitrogen gas inlet, 172 parts of methacrylic acid, 217 parts of trimethylchlorosilane, And triethylamine 202
At 25 ° C while paying attention to the rise of the reaction temperature.
The reaction was continued for hours. Thereafter, triethylamine hydrochloride was passed through, and the solution was purified by distillation under reduced pressure to obtain a target vinyl monomer. Hereinafter, this vinyl monomer is referred to as [M-
1].

Reference Example 2 [Preparation of Vinyl Monomer (A)] Reference Example 1 was repeated except that 144 parts of acrylic acid, 189 parts of dimethylchlorosilane and 202 parts of triethylamine were charged into the same reactor as in Reference Example 1, and reacted. The same operation as in was repeated to obtain the desired vinyl monomer.

 Hereinafter, this vinyl monomer is abbreviated as [M-2].

Reference Example 3 [Preparation of vinyl monomer (A)] In a reactor similar to that of Reference Example 1, 172 parts of methacrylic acid was added.
306 parts of trimethylbromosilane and triethylamine 2
The same operation as in Reference Example 1 was repeated except that 02 parts were charged and reacted, to obtain a desired vinyl monomer.

 Hereinafter, this vinyl monomer is abbreviated as [M-3].

Production Example 1 [Preparation of vinyl polymer (I)] In a reactor similar to that of Reference Example 1, 667 parts of xylene was charged.
The temperature was raised to 10 ° C. Styrene 200 parts at that temperature, n- butyl methacrylate 443 parts, ACRYESTER [Mitsubishi rayon Co., trade name C ₁₂ / C ₁₃ becomes mixed synthetic lauryl alcohol acrylate esters] 150 parts, reference A mixture of 207 parts of [M-1] obtained in Example 1, 10 parts of t-butyl peroxyoctoate (hereinafter abbreviated as TBPO) and 333 parts of xylene was added dropwise over 4 hours. Thereafter, the reaction was continued at the same temperature for 8 hours to obtain a resin solution having a nonvolatile content (hereinafter abbreviated as NV) of 50% and a number average molecular weight (hereinafter abbreviated as n) of 13000.

Production Examples 2 to 5 [Preparation of Vinyl Polymer (I)] and Production Example 6 [Preparation of Vinyl Polymer (I) for Comparative Control] 200 parts of styrene used in Production Example 1, n-butyl methacrylate 443 parts, acrylic ester SL 150 parts, [M-1]
The same operation as in Production Example 1 was repeated except that the monomers and the initiator amounts shown in Table 1 were used instead of 207 parts and TBPO, to obtain vinyl polymers (I). In Table 1, n is also described.

Production Example 7 [Preparation of vinyl polymer for comparison (I)] In a reactor similar to that of Reference Example 1, 1643 parts of xylene was charged.
The temperature was raised to 130 ° C. At that temperature 200 parts of styrene, 443 parts of n-butyl methacrylate, 150 parts of acrylate SL,
[M-1] A mixture of 207 parts, 150 parts of TBPO and 690 parts of xylene was added dropwise over 8 hours. Thereafter, the reaction was continued at the same temperature for 4 hours to obtain a resin solution having an NV of 30% and n850. Hereinafter, it is abbreviated as [I-7].

Production Example 8 [Preparation of Comparative Vinyl Polymer (I)] Instead of the vinyl monomer mixture used in Production Example 1,
The same operation as in Production Example 1 was repeated except that 200 parts of styrene, 590 parts of n-butyl methacrylate, 100 parts of acrylester SL, and 110 parts of methacrylic acid were used.
A resin solution of Mn15000 was obtained. Hereinafter, this is referred to as [I-8]
Abbreviated.

Examples 1 to 6 and Comparative Examples 1 to 5 Clear paints were separately prepared according to a conventional coating method according to the mixing ratio (parts by weight) shown in Table 2, and then xylene / toluene / ethyl acetate = 30/50. / 20 (weight ratio) diluted with a mixed solvent to the spray viscosity, spray-coated on a zinc phosphate treated steel sheet so that the dry coating film becomes 30 μm,
A cured coating film was obtained by heating at 60 ° C. for 30 minutes. Table 2 shows the results of evaluating the physical properties of each coating film thus obtained. The evaluation of the physical properties was performed after the forced drying was allowed to stand at room temperature for 3 days.

From the performance evaluation results in Table 2, it can be seen that the composition of the present invention is excellent in physical properties and long-term storage stability of the cured coating film, and has one-pack normal-temperature or low-temperature curability.

Claims (3)

(57) [Claims] (A) 1 to 100% by weight of a vinyl monomer having at least one unsaturated double bond and a silyl ester group in one molecule, and (B) a copolymer other than the above (A) A curing agent (II) having a reactivity with a carboxyl group produced from the polymer (I) is added to a vinyl copolymer (I) comprising 99 to 0% by weight of a polymerizable vinyl monomer. A resin composition for a coating composition. 2. The coating resin composition according to claim 1, wherein a dissociation accelerating catalyst is blended with said coating resin composition. 3. The resin composition for a paint according to claim 1, wherein a water binder is blended into said resin composition for a paint.