JP2001192621A - Coating material composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a coating material having a low smelling, low toxicity and small effect to atmospheric pollution, exhibiting good working and finishing properties, and excellent in drying property, curing property, long-term weather resistance, antifoulancy and resistance to the infiltration of the soiling from just after its application. SOLUTION: This coating material composition of which >=50 wt.% total solvent is an aliphatic hydrocarbon, contains (A) a synthetic resin containing a dispersion type resin and 5-30 wt.% silicone component having 0.05-5 KOH mg/g amine value and 15-100 KOH mg/g hydroxyl value based on SiO2 in the resin solid portion, (B) a compound of a condensed material having 4-10 mean degree of condensation of tetraalkoxysilane, in which the condensed compounds having 1-3C alkyl and 4-12C alkyl present as mixed and the ratio of their mixed presence of the compound having 4-12C alkyl is 5-50% of the total alkyl groups, and (C) an isocyanate compound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating composition used for surface finishing of various materials such as metal, glass, porcelain tile, concrete, siding board, extruded plate, plastic and the like.

[0002]

2. Description of the Related Art Conventionally, paint finishing has been performed to protect the frame of buildings, civil engineering structures, and the like, to impart design properties, and to improve aesthetics. An aromatic hydrocarbon solvent such as toluene and xylene has been used. A strong solvent type paint as a medium is often used. On the other hand, in recent years, awareness of the environment and health has increased, and in consideration of toxicity to the human body, work safety, and the effect on air pollution, such aromatic hydrocarbon solvents have been considered. Moves to curb the use of are increasing.

In order to cope with such a movement, it has been demanded to switch to a weak solvent type paint using an aliphatic hydrocarbon solvent. Such a weak solvent type paint is preferable as an environmentally friendly type paint because it has the advantages that it is less toxic, has higher working safety, and has less influence on air pollution than the strong solvent type paint. Things.

[0004] As a coating method, roller coating, brush coating and the like have been attracting attention instead of spray coating which has been frequently used in the past. In spray coating, the proportion of paint that scatters without being applied to the workpiece is high, and the amount of solvent released into the atmosphere is large, whereas in roller coating or brush coating, paint is applied directly to the workpiece. Therefore, the material can be used without waste, and the influence on the periphery is small. However, when such a coating method is used, in particular, it is required that no sagging occurs, the leveling property is good, and the finish property is excellent.

[0005] Further, when performing coating, there is a demand for a material that can be directly applied to the base, regardless of the state or type of deterioration of the base. This is because, depending on the state and type of deterioration of the base, adhesion to the base cannot be ensured, and it is necessary to select a strong solvent type undercoat suitable for the base and apply it in advance.

Further, it is desired that the formed coating film has excellent stain resistance and weather resistance. Use of such a paint having excellent stain resistance and weather resistance can maintain the aesthetics over a long period of time and further extend the life of the coating film, so that the recoating cycle can be extended.
Conversely, if the formed coating film becomes dirty or deteriorates early, it must be applied frequently, and the solvent is released each time, resulting in an increase in the amount of solvent released. Would.

On the other hand, in recent years, the decrease in the number of skilled workers has become a social problem, and there is concern in the art. On the other hand, inexperienced workers or ordinary consumers can easily use the product even when painting, and the finish is good.Also, after painting, the aesthetics and frame protection are maintained for a long time, and maintenance is free. It is desired to be. From these aspects, the need for materials that reduce solvent odor and toxicity, can be applied directly to many bases, have good workability and finish, and have excellent stain resistance and weather resistance Is growing.

[0008]

As a stain-resistant high-durability paint, WO 94/06870 proposes to incorporate a specific organosilicate and / or a condensate thereof into the paint. This is a technique in which a specific organosilicate is blended to make the surface of the coating film hydrophilic, making it difficult for oily contaminants to adhere, and even if it adheres, it is washed away with water drops such as rainfall.

However, most of such anti-stain, high-durability paints are generally strong solvent-based paints using an aromatic hydrocarbon solvent such as toluene or xylene as a medium. Even if the technology of this publication is applied to a weak solvent type paint using an aliphatic hydrocarbon solvent as a medium, the resin film becomes cloudy or stains are generated by short-term outdoor exposure, which is satisfactory. You can't get anything. In weak solvent paints,
In fact, it is not possible to obtain a highly practical coating simply by adding a general alkyl silicate.

The weak solvent type paint is preferable as an environmentally friendly type paint, but generally has a problem that its drying property is inferior to the strong solvent type paint. This is due to the fact that aliphatic hydrocarbon solvents used in weak solvent type paints have a higher boiling point and lower volatility than aromatic hydrocarbon type solvents, and are common problems with weak solvent type paints. It is. In particular,
Depending on conditions such as temperature and humidity, compared to strong solvent type paint,
In some cases, remarkably long time is required for drying and curing of the coating film. In such a case, it takes time for the desired properties of the coating film to be exhibited, and sufficient resistance may not be exerted against stains adhered in the course of drying and curing.

[0011]

Means for Solving the Problems In order to solve such a problem, the present inventors have conducted intensive studies and as a result, they have found that a specific amount of amino group and hydroxyl group is contained as a functional group containing a dispersed resin. By using the silicone-modified synthetic resin contained as a binder, and blending this resin with a low-condensation product of tetraalkoxysilane having a specific structure, it has low odor, low toxicity, and little influence on air pollution. It is hard to cause peeling, it can be painted with a relatively thick film, it has good leveling properties and excellent aesthetics, and it has good drying and curing properties after painting,
The present inventors have found that a paint having excellent long-term weather resistance, exhibiting low contamination immediately after coating, and having excellent resistance to stain penetration can be obtained, thereby completing the present invention.

That is, the present invention relates to the following coating composition. 1. A paint composition in which 50% by weight or more of the total solvent in the paint is an aliphatic hydrocarbon, which comprises (A) a dispersible resin, an amine value of 0.05 to 5 KOH mg / g, and a hydroxyl value of 15 (B) a condensate of tetraalkoxysilane having an average average degree of condensation of 4 to 10, which is a synthetic resin containing 5 to 30% by weight of a silicone component in terms of SiO2 in a resin solid content. It is assumed that alkyl groups having 1 to 3 carbon atoms and 4 to 12 carbon atoms are mixed in the product, and the mixing ratio of alkyl groups having 4 to 12 carbon atoms is 5% of all alkyl groups in the condensate. (B) is 1.0 to 50.0 parts by weight in terms of SiO2 with respect to 100 parts by weight of the resin solid content of (A). ) Is 0.7 to 2.0 in NCO / OH ratio. A coating composition characterized in that it contains a coating composition as described above. 2. Further, (D) a polyalkylene oxide chain having 2 to 40 repeating units and a weight average molecular weight of 1
50 to 3500 alkoxysilane compounds are added in a solid content of 0.1 to 2 parts per 100 parts by weight of the resin solid content of (A).
It is characterized by containing 0 parts by weight. The coating composition according to any one of the preceding claims. 3. 30% by weight or more of the total resin solid content is a dispersion type resin. Or 2. 3. The coating composition according to item 1.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on its embodiments.

[0014] The composition of the present invention comprises (A) a silicone-modified synthetic resin containing a dispersed resin and containing specific amounts of amino groups and hydroxyl groups, mainly using an aliphatic hydrocarbon as a solvent.
(B) a tetraalkoxysilane condensate of a specific structure,
(C) An isocyanate compound is an essential component. In the present invention, the mechanism of action is not clear, but by combining a silicone-modified resin containing a specific amount of an amino group as a functional group with a tetraalkoxysilane condensate of a specific structure, the difference in internal energy between the two results in the formation of a silane compound. Surface orientation is enhanced, and an inorganic layer can be quickly formed on the surface of the coating film.Also, the dryness and curability of the entire coating film have been improved, and the coating has excellent long-term weather resistance. A coating film having excellent penetration resistance can be obtained. In addition, by including the dispersion type resin, a suitable thixotropy is imparted, sagging hardly occurs, a relatively thick film can be applied, and a coating excellent in leveling property can be obtained. Furthermore, due to the synergistic effect of silicone and urethane,
Excellent adhesion to a wide variety of substrates.

[Solvent] The coating composition of the present invention uses a non-aqueous solvent as a solvent, and is a so-called weak solvent type coating composition in which 50% by weight or more of all solvents are aliphatic hydrocarbons. . Such an aliphatic hydrocarbon-based solvent is characterized in that it has lower toxicity, higher operational safety, and less influence on air pollution than an aromatic hydrocarbon-based solvent. Examples of the aliphatic hydrocarbon-based solvent include, for example, n-hexane, n-pentane, n-octane, n-nonane, n-decane, n-undecane, n-dodecane, terpine oil and mineral spirit. . In addition to such an aliphatic hydrocarbon-based solvent, a non-aqueous solvent commonly used for paints can also be used, but the ratio is less than 50% by weight. Such non-aqueous solvents include toluene, xylene, aromatic hydrocarbon solvents such as solvent naphtha, ethyl acetate,
Examples thereof include butyl acetate, methyl ethyl ketone, and methyl isobutyl ketone. In the present invention, one or more of such non-aqueous solvents are used in combination such that at least 50% by weight is an aliphatic hydrocarbon. When the amount of the aliphatic hydrocarbon is less than 50% by weight, the odor may be increased and the work safety may be reduced, or lifting may occur when the coating is performed on the existing coating film.

[(A) Synthetic Resin] In the present invention, the resin contains a dispersed resin, has an amine value of 0.05 to 5 KOH mg / g, a hydroxyl value of 15 to 100 KOH mg / g, and is contained in 100 parts by weight of resin solid content. A synthetic resin containing 5 to 30 parts by weight of a silicone component in terms of SiO 2 (hereinafter referred to as “component (A)”) is used.

The component (A) has an amine value of 0.05 to 5K.
OH mg / g, preferably 0.1 to 3 KOH mg / g. That is, the resin has an amino group in the resin skeleton so that the amine value in the whole resin falls within such a range. When the amine value is within this range, it contributes to the formation of an inorganic layer on the surface of the coating film, improves the dryness and curability of the entire coating film, improves stain resistance immediately after coating, and provides long-term weather resistance. A coating film having excellent properties is obtained.

Specific examples of the compound for imparting an amino group include a primary amino group-containing monomer, a secondary amino group-containing monomer, and a tertiary amino group-containing monomer. One or more of these can be used.

Examples of the primary amino group-containing monomer include aminomethyl (meth) acrylate, aminoethyl (meth) acrylate, aminopropyl (meth) acrylate, aminobutyl (meth) acrylate, p-aminostyrene, allylamine and the like. Is mentioned.

Examples of the secondary amino group-containing monomer include monomethylaminoethyl (meth) acrylate,
N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N-methylolacrylamide,
N- (4-anilinophenyl) methacrylamide and the like can be mentioned.

Examples of the tertiary amino group-containing monomer include, for example, dimethylaminomethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, dimethylaminobutyl (meth) acrylate, diethylaminoethyl ( Meth) acrylate, diethylaminopropyl (meth) acrylate, diethylaminobutyl (meth) acrylate, methylethylaminoethyl (meth) acrylate,
Dipropylaminoethyl (meth) acrylate, dibutylaminoethyl (meth) acrylate, dibutylaminopropyl (meth) acrylate, dibutylaminobutyl (meth) acrylate, dihexylaminoethyl (meth) acrylate, dioctylaminoethyl (meth) acrylate, etc. Ester of acrylic acid or methacrylic acid; dimethylaminomethyl (meth) acrylamide, dimethylaminoethyl (meth) acrylamide, dimethylaminopropyl (meth) acrylamide, dimethylaminobutyl (meth) acrylamide, diethylaminoethyl (meth) acrylamide, diethylaminopropyl (Meth) acrylamide, diethylaminobutyl (meth) acrylamide, methylethylaminoethyl (meth) acrylamide, Propyl aminoethyl (meth) acrylamide, dibutyl aminoethyl (meth) acrylamide, dibutyl aminopropyl (meth) acrylamide, dibutyl aminobutyl (meth) acrylamide, dihexylaminoethyl (meth) acrylamide,
(Meth) acrylamide compounds such as dihexylaminopropyl (meth) acrylamide and dioctylaminopropyl (meth) acrylamide; styrene derivatives such as dimethylaminoethylstyrene, diethylaminoethylstyrene, dipropylaminoethylstyrene and dioctylaminoethylstyrene; 2-vinyl Pyridine, 4-vinylpyridine, 5-methyl-2-vinylpyridine, 5-
Examples include vinyl compounds containing a pyridyl group such as ethyl-2-vinylpyridine.

In the present invention, as the amino group, those containing a tertiary amino group in which three carbon atoms are bonded to a nitrogen atom can be most preferably used. This is because the NH group present in the primary amino group and the secondary amino group easily reacts with the NCO group of the isocyanate compound and reacts faster than urethane bond formation to form a urea bond. Because it has some effect on However, even if NH
Even if a group is present, there is no practical problem even if an amino group having NH is used if the total content is appropriately adjusted.

The component (A) has a hydroxyl group in the resin skeleton. Such hydroxyl groups are provided by the polyol compound. The hydroxyl value in all resins is 1
5-100 KOHmg / g. Hydroxyl value is 15KO
When it is smaller than Hmg / g, the crosslinking density is low.
Poor physical properties and stain resistance of various coatings. Conversely, 100KOHm
When it is larger than g / g, the crosslink density becomes high and the surface orientation of the (B) tetraalkoxysilane low-condensate is undesirably inhibited.

Examples of the polyol compound include polyether polyol, polyester polyol, and acrylic polyol. Hereinafter, each polyol will be exemplified.

Polyether polyol As the polyether polyol, one or two polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, glycerin, trimethylolpropane, pentaerythritol, glucose, sorbitol, and sucrose can be used.
Propylene oxide, ethylene oxide,
Examples thereof include polyols obtained by adding one or more kinds such as butylene oxide and styrene oxide, and polyoxytetramethylene polyols obtained by adding tetrahydrofuran to the polyhydric alcohol by ring-opening polymerization.

Polyester polyol As the polyester polyol, ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, cyclohexanedimethanol, glycerin, trimethylolpropane, pentaerythritol or other low molecular weight polyhydric alcohols are used. Or more and one or more of glutaric acid, adipic acid, pimelic acid, speric acid, sebacic acid, terephthalic acid, isophthalic acid, dimer acid, hydrogenated dimer acid or other low molecular dicarboxylic acids or oligomeric acids Condensation polymer, propiolactone, caprolactone,
Examples include polyols such as ring-opening polymers of ring-opening esters such as valerolactone.

Acrylic polyol In an acrylic copolymer, β-hydroxyethyl acrylate, β-hydroxypropyl acrylate, 3-hydroxypropyl acrylate, β-hydroxybutyl acrylate, 4-hydroxybutyl acrylate, β-hydroxybutyl acrylate Hydroxyalkyl esters of acrylic acid such as hydroxypentyl or similar hydroxyalkyl esters of methacrylic acid; furthermore, glycerin, acrylate monoesters of polyhydric alcohols such as trimethylolpropane or methacrylic monoesters similar thereto, N-methylol acrylamide Alternatively, an acrylic polyol having two or more hydroxyl groups in one molecule such as a copolymerized monomer of a monoethylenically unsaturated monomer having a hydroxyl group such as N-methylol methacrylamide can be used.

Other polyols In addition, phenolic resin polyols, epoxy polyols, polybutadiene polyols, polyisoprene polyols, polyester-polyether polyols, polymer polyols obtained by adding or dispersing polymers such as acrylonitrile and styrene to vinyl, urea-dispersed polyols, carbonates Polyols and the like can be used as the polyol of the present invention.

Among such polyols, it is preferable to use an acrylic polyol, particularly when considering the weather resistance of a coating film formed from the composition of the present invention.

The component (A) further contains a silicone component. As the form of such a silicone component, a chain form, a branched form, a cyclic form, and the like can be used.

The content of the silicone component is 5 to 30% by weight in terms of SiO2 in the resin solid content. If the amount is less than 5% by weight, the effect of improving long-term weather resistance is difficult to obtain, and sufficient adhesion to the base may not be ensured. Three
When the content is more than 0% by weight, the coating film becomes hard, brittle, and easily cracks.

The method of introducing silicone into the component (A) is not particularly limited, and various methods can be employed. Examples thereof include a method of copolymerizing a silicone compound having a polymerizable double bond, A method of reacting a functional group of the above with a silicone compound having a functional group capable of reacting with the functional group; a method of reacting a reactive silyl group-containing compound with a resin obtained by copolymerizing a reactive silyl group-containing monomer; After reacting the functional group with a coupling agent having a functional group capable of reacting with the functional group, and then reacting a reactive silyl group-containing compound.

Examples of the combination of the functional groups include a hydroxyl group and an isocyanate group, a hydroxyl group and a carboxylic anhydride group, an amino group and an isocyanate group, a carboxyl group and an epoxy group, an amino group and an epoxy group, and an alkoxysilyl group. Can be

In the above, the reactive silyl group includes
An alkoxyl group, a phenoxy group, a mercapto group, an amino group, a halogen, etc. are bonded to a silicon atom. As the reactive silyl group-containing compound, those having two or more reactive silyl groups in one molecule are used. For example, tetrafunctional alkoxysilanes such as tetraethoxysilane, tetramethoxysilane and tetrabutoxysilane; Methoxysilane, methyltriethoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltributoxysilane, propyltrimethoxysilane, propyltriethoxysilane,
Trifunctional alkoxysilanes such as butyltrimethoxysilane, butyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, and phenyltributoxysilane; dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldibutoxysilane, diethyldimethoxysilane, Diethyldiethoxysilane, dipropyldimethoxysilane, dipropyldiethoxysilane, dibutyldimethoxysilane, dibutyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, diphenyldibutoxysilane, methylphenyldimethoxysilane, methylphenyldiethoxysilane, etc. Bifunctional alkoxysilanes; tetrachlorosilane, methyltrichlorosilane, ethyltrichlorosilane, propyltrichlorosilane Chlorosilanes such as phenyltrichlorosilane, vinyltrichlorosilane, dimethyldichlorosilane, diethyldichlorosilane, diphenyldichlorosilane, and methylphenyldichlorosilane; tetraacetoxysilane, methyltriacetoxysilane, phenyltriacetoxysilane, dimethyldiacetoxysilane, Acetoxysilanes such as diphenyldiacetoxysilane and the like;
More than one species can be used. Further, a compound having one reactive silyl group in one molecule can be used in combination.

The reactive silyl group-containing monomer in the above is a compound containing a reactive silyl group and a polymerizable double bond, such as vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri-n-butoxysilane, and the like.
Vinyl tris (β-methoxyethoxy) silane, allyltrimethoxysilane, trimethoxysilylethyl vinyl ether, triethoxysilylethyl vinyl ether,
Trimethoxysilylpropyl vinyl ether, triethoxysilylpropyl vinyl ether, γ- (meth) acryloyloxypropyltrimethoxysilane, γ- (meth) acryloyloxypropyltriethoxysilane,
γ- (meth) acryloyloxypropylmethyldimethoxysilane, vinylmethyldimethoxysilane, methyldimethoxysilylethylvinylether, methyldimethoxysilylpropylvinylether, etc., and one or more of these can be used.

The coupling agent is, for example, a compound having at least one or more alkoxysilyl groups and other substituents in one molecule. Specific examples of the coupling agent include β- (3,4 epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropyltriethoxysilane, and N- ( β-aminoethyl) -γ-aminopropylmethyldimethoxysilane, N- (β-aminoethyl) -γ-aminopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, isocyanate functionality Examples thereof include silane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, and γ-methacryloxypropyltriethoxysilane, and one or more of these can be used.

The component (A) includes one dispersed in a non-aqueous solvent (dispersed resin). The dispersion type resin is a resin which is dispersed as resin particles in a non-aqueous solvent, and has both a resin portion that is soluble in a non-aqueous solvent and a resin portion that is not soluble in a non-aqueous solvent. The resin portion soluble in a non-aqueous solvent is one having a solubility in a non-aqueous solvent of 99.0% by weight or more. This depends on the type of non-aqueous solvent, but may be any as long as it can be dissolved in the non-aqueous solvent to be finally dispersed. Conversely, the resin portion that does not dissolve in the non-aqueous solvent is one that does not dissolve in the non-aqueous solvent at all or has a very small amount (for example, the solubility is less than 1.0% by weight). This also depends on the type of the non-aqueous solvent, but a solvent which hardly dissolves in the non-aqueous solvent to be finally dispersed may be used. In the component (A), it is desirable that the total content of the resin is 30% by weight or more of the dispersed resin. As a result, a suitable thixotropy is imparted as a viscous behavior, a sagging hardly occurs, a relatively thick film can be applied, a leveling property is good, and a paint excellent in finish property can be obtained. As the component (A), a dispersible resin and a soluble resin of a type dissolved in a non-aqueous solvent can be used in combination.

The SP of the component (A) is usually 6.5 to 9.
5 is used. By using such SP, it becomes possible to dissolve and / or disperse even in a solvent having a weak dissolving power called a weak solvent. it can.

As the component (A) of the present invention, those having a weight average molecular weight of 5,000 to 200,000 can be used. In particular, in the case of a dispersion-type resin, 10,000 to 100
000 is preferred. When the weight average molecular weight is less than 5,000, appropriate viscosity is not obtained as a paint, and the properties of each coating film are inferior. On the contrary, when the weight average molecular weight is more than 200,000, the sharpness and gloss of the coating film are deteriorated, which is preferable. Absent.

The glass transition point of the component (A) is from -10 ° C to 1
The temperature is preferably 50C, more preferably 10C to 100C. When the temperature is lower than -10 ° C, the soil removal property and the soil recovery property are poor. When the temperature is higher than 150 ° C, flexibility and durability are poor.

In the component (A), by using a fluorine-containing polyol, the long-term weather resistance and the effect of preventing contamination can be further improved. Such a polyol can be obtained by copolymerizing perfluoroolefins such as tetrafluoroethylene, chlorotrifluoroethylene and hexafluoropropylene, and fluoroolefins such as vinyl fluoride and vinylidene fluoride.

[(B) Tetraalkoxysilane Low Condensate] In the present invention, a tetraalkoxysilane low condensate having a specific structure (hereinafter, referred to as “component (B)”) is blended. The component (B) is a condensate of tetraalkoxysilane having an average degree of condensation of 4 to 10, wherein the alkyl group in the condensate contains a mixture of alkyl groups having 1 to 3 carbon atoms and 4 to 12 carbon atoms. Wherein the alkyl group having 4 to 12 carbon atoms is 5 to 50% of the total alkyl groups in the condensate.

The component (B) is a low-condensation product of tetraalkoxysilane, but the one having a high degree of condensation (average degree of condensation is greater than 10) and a high molecular weight is difficult to manufacture, and is difficult to handle due to an increase in viscosity. It is not preferable because it is inconvenient. Conversely, those having an average degree of condensation of 3 or less and a low molecular weight are not preferred because they have high volatility and are also inconvenient to handle.

In addition, the compatibility of the component (A) with the component (A) is drastically improved because the alkyl group in the component (B) contains one having 1 to 3 carbon atoms and 4 to 12 carbon atoms. A film having excellent surface orientation and excellent film properties can be formed. If the alkyl group is only an alkyl group having 1 to 3 carbon atoms, the compatibility with the component (A) is poor and the surface orientation is poor. Further, when only an alkyl group having 4 to 12 carbon atoms is used, the stain resistance is remarkably deteriorated, which is not preferable. The presence of an alkyl group having 13 or more carbon atoms is not preferred because stain resistance is deteriorated. Further, as the number of carbon atoms in the alkyl group increases, the above-mentioned hydrolysis reaction tends to be less likely to occur, and therefore it is not preferable that only alkyl groups having a large number of carbon atoms exist. The component (B) is such that about 5 to 50% of the total alkyl groups of the low-condensate are alkyl groups having 4 to 12 carbon atoms. Is preferred because of its excellent stain resistance.

The component (B) of the present invention can be produced by the following method, but is not limited thereto. General formula

Embedded image (Wherein R ^{1 to} R ⁴ are a mixture of an alkyl group having 1 to 3 carbon atoms and an alkyl group having 4 to 12 carbon atoms).
0, condensation is performed so that the weight average molecular weight is 500 to 2500. The condensation method is based on a known method.

In the formula, a part of the alkyl group represented by R ^{1 to} R ⁴ is
By having a mixture of one having 1 to 3 carbon atoms and one having 4 to 12 carbon atoms, the compatibility with the component (A) is dramatically improved, the surface orientation is excellent, and the coating film properties are excellent. A film can be formed. When such a tetraalkoxysilane is condensed to form a low condensate, about 5 to 50% of all alkyl groups are alkyl groups having 4 to 12 carbon atoms (A). It is preferable because it has excellent compatibility with the components and excellent stain resistance of the coating film.
In order to make the alkyl group of about 5 to 50% of the total, at the time of condensation, another alkyl silicate (the alkyl group having 1 to 3 carbon atoms) is mixed and condensed. It is an effective means.

Specific examples include, but are not limited to, low-condensates such as monobutoxytrimethoxysilane, monopentoxytrimethoxysilane, monohexoxytrimethoxysilane, dibutoxydiethoxysilane and the like. .

(A) General formula

Embedded image (Wherein, R ⁵ is an alkyl group having 1 to 3 carbon atoms, and n is 4
An alkyl silicate low-condensate represented by the following general formula (b):

Embedded image (Wherein R ⁶ is an alkyl group having 4 to 12 carbon atoms) (hereinafter referred to as “component (b) component”) using about 5 to 5 parts of the alkyl group portion of component (a). Transesterify 50%.

As the component (a), specifically, tetramethyl silicate, tetraethyl silicate, tetra-n
Low-condensates such as -propyl silicate and tetra-i-propyl silicate. In particular, tetramethyl silicate and tetraethyl silicate are generally used. The average degree of condensation is preferably from 4 to 10, and it is not preferable that the average degree of condensation is large or small because handling becomes inconvenient. As the component (b), specifically, n-butyl alcohol, n-amyl alcohol, n-hexyl alcohol, n-heptyl alcohol, n-octyl alcohol, n-nonyl alcohol, n-decyl alcohol, n
-Undecyl alcohol and n-dodecyl alcohol.

When the component (a) is transesterified with the component (b), all the alkyl groups (R ⁵ ) of the component (a)
Is not transesterified to the alkyl group (R ⁶ ) of the component (b), but a transesterification of about 5 to 50% of the total alkyl group of the component (a) is used. As for the exchange ratio, the ester exchange may be performed using 1 to 12 moles of the component (b) with respect to 1 mole of the component (a). The exchange ratio is appropriately adjusted depending on the average degree of condensation of the component (a).
By transesterifying 0%, the compatibility with the component (A) and the stain resistance of the coating film can be made excellent. When the transesterification rate is low, the compatibility becomes poor and the surface orientation becomes insufficient. When the transesterification rate is high, the hydrolysis reaction is less likely to occur, the coating film is less likely to be hydrophilic, and the stain resistance tends to be worse.

The component (B) thus produced is
With respect to 100 parts by weight of the resin solid content of the component (A), SiO
1.0 to 50.0 parts by weight, preferably 2.0 to 3 parts by weight in terms of ₂
0.0 parts by weight can be added. This is because if the amount is less than 1.0 part by weight, the hydrophilicity of the coating film is not sufficient, so that the stain resistance is inferior. If the amount exceeds 50.0 parts by weight, the appearance of the cured coating film deteriorates and cracks occur. Is to come out.

The SiO ₂ conversion in the present invention means
After the compound having a Si—O bond is completely hydrolyzed, it is converted into silica (SiO ₂ ) when calcined at 900 ° C. and expressed in terms of the remaining weight. In general, alkoxysilane, silicate, and the like have a property of reacting with water to cause a hydrolysis reaction to form silanol, and to cause a condensation reaction between silanols or silanol and alkoxy. When this reaction is carried out to the ultimate, silica (SiO
₂ ) These reactions are represented by the general formula: RO (Si (OR) ₂ O) _n R + (n + 1) H ₂ O → n
It is represented by a reaction formula of SiO ₂ + (2n + 2) ROH, and is obtained by converting the amount of the remaining silica component based on the reaction formula.

[(C) Isocyanate Compound] When a polyol is contained in the component (A), an isocyanate compound (hereinafter referred to as “component (C)”) is blended and crosslinked and cured to form a coating film. Examples of such a curing agent include Vernock DN-990, DN-991, and DN-992.
(Both manufactured by Dainippon Ink and Chemicals, Inc.), Duranate TSA (manufactured by Asahi Kasei Corporation), Takenate D-1
77N (manufactured by Takeda Pharmaceutical Co., Ltd.), Desmodur Z
-4270 (manufactured by Sumitomo Bayer Urethane Co., Ltd.). These curing agents can be suitably used because they dissolve in a solvent having a low dissolving power. In addition, toluene diisocyanate (TDI), 4,4-diphenylmethane diisocyanate (pure-MDI), polymeric MDI, xylylene diisocyanate (XDI), hexamethylene diisocyanate (HMDI), isophorone diisocyanate (IPDI), hydrogenated XDI, hydrogenated MD
The isocyanate monomer such as I is derivatized by allohanate, biuret, dimerization (uretidione), trimerization (isocyanurate), adduct, carbodiimide reaction, etc., and a mixture thereof is dissolved in a solvent having strong dissolving power It is also possible to use.

Further, these components (C) can be used in the form of a blocked isocyanate using a blocking agent such as alcohols, phenols, ε-caprolactam, oximes and active methylene compounds. These are also preferably used as a solution with a solvent.

The mixing of the component (C) and the component (A) is performed at a ratio such that the NCO / OH ratio is 0.7 to 2.0, preferably 0.8 to 1.5. At this time NC
When the O / OH ratio is smaller than 0.7, the crosslinking ratio of the coating film is lowered, and the curability and durability are deteriorated. In addition, the contaminants enter into the molecules having a low density of the coating film. Even if it is carried out, it is difficult to remove the contaminants, resulting in poor pollution recovery. On the other hand, if it is larger than 2.0, unreacted isocyanate remains, deteriorating the initial drying property, causing tackiness on the surface called tack and contaminants being physically attached, On the contrary, the initial contamination is inferior.

[(D) Alkoxysilane Compound Containing Polyalkylene Oxide Chain] Next, in the present invention, (D) an alkoxysilane compound containing a polyalkylene oxide chain (hereinafter referred to as “component (D) component”) is added. In addition, it becomes possible to make the coating film surface more hydrophilic than the initial stage, and it is possible to obtain a stain resistance superior to the initial stage. The component (D) is a compound having an alkylene oxide repeating unit and at least one alkoxysilyl group. In the polyalkylene oxide repeating unit of the component (D), the alkylene portion has 2 to 4 carbon atoms, and the number of repeating units is 2 to 40, preferably 2 to 20.

In such a component (D), both ends of the polyalkylene oxide chain may be alkoxysilyl groups, and one end may be an alkoxysilyl group and the other end may be another functional group. Good. Examples of such a functional group that can be present at one end include a vinyl group,
Examples include a hydroxyl group, an epoxy group, an amino group, an isocyanate group, and a mercapto group. Particularly, the use of a hydroxyl group (hydroxyl group) is preferred. Further, the functional group may be bonded to an alkoxysilyl group via a urethane bond, a urea bond, a siloxane bond, an amide bond, an ether bond, or the like.

As the component (D), for example, those synthesized by reacting a compound containing a polyalkylene oxide chain with a compound containing an alkoxysilyl group (hereinafter referred to as a coupling agent) can be used.

The polyalkylene oxide chain-containing compound preferably has a weight average molecular weight of 150 to 3500,
200 to 1500 are more preferred. When the weight-average molecular weight is less than 150, the cured film finally obtained is inferior in hydrophilicity, and a cleaning effect of contaminants due to rainfall cannot be obtained. When the weight-average molecular weight exceeds 3500, the water resistance of the cured product and Hardness decreases.

Examples of such polyalkylene oxide chain-containing compounds include polyethylene glycol, polyethylene-propylene glycol, polyethylene-tetramethylene glycol, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, polyoxyethylene diglycolic acid, and polyethylene glycol. Examples include vinyl ether, polyethylene glycol divinyl ether, polyethylene glycol allyl ether, and polyethylene glycol diallyl ether. The polyalkylene oxide chain-containing compound can be selected from one kind or a combination of two or more kinds. When two or more types of monomers are used, they may be random copolymers or block copolymers.

On the other hand, the coupling agent is, for example, a compound having at least one or more alkoxysilyl groups and other substituents in one molecule. Specific examples of the coupling agent include β- (3,4 epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropyltriethoxysilane, and N- ( β-aminoethyl) -γ-aminopropylmethyldimethoxysilane, N
-(Β-aminoethyl) -γ-aminopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane,
γ-aminopropyltriethoxysilane, isocyanate-functional silane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-methacryloxypropyltriethoxysilane, and the like.

The synthesis of the component (D) is not particularly limited, but a compound containing a polyalkylene oxide chain and a coupling agent are separately prepared. For example, for each compound having a polymerizable double bond, a radical polymerization initiator is used. In addition to copolymerization using an amino group, it can be synthesized by a known method such as an addition reaction of an amino group / epoxy group, an isocyanate group / hydroxyl group or an isocyanate group / amino group. It can also be synthesized by a method in which ethylene oxide is ring-opened to an alkoxysilyl compound having an active hydrogen group such as a primary or secondary amino group.

When the copolymerization is carried out using a radical polymerization initiator, at least one or more of the polyalkylene oxide chain-containing compounds having a polymerizable double bond and at least one or more of the coupling agents may be used in a non-reactive, appropriate manner. It can be obtained by reacting in a suitable solvent. At this time, as the radical polymerization initiator used, for example, benzoyl peroxide, dichlorobenzoyl peroxide, 2,5-
Di (peroxybenzoate) hexyne-3,1,3-
Bis (t-butylperoxyisopropyl) benzene,
Examples include perester compounds such as t-butyl perbenzoate, azo compounds such as azobisisobutyronitrile and dimethylazobutyrate, and organic peroxides.

As the polyalkylene oxide chain-containing compound having a polymerizable double bond, for example, polyethylene glycol vinyl ether can be used, and γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyl Methyldiethoxysilane and γ-methacryloxypropyltriethoxysilane can be used alone or in combination of two or more.

In the case of synthesis by an isocyanate / polyol addition reaction, for example, a compound having a hydroxyl group at a terminal such as polyethylene glycol is used for a compound containing a polyalkylene oxide chain, and an isocyanate such as an isocyanate-containing coupling agent is used for a coupling agent. Compounds having a group are mixed and synthesized. In this synthesis method, it is also possible to use an organometallic reaction catalyst known in the field of polyurethane synthesis, such as dibutyltin dilaurate, dibutyltin dimaleate, or dioctyltin dimaleate.

As the component (D) synthesized by the above-mentioned reaction, a compound obtained by adding a coupling agent to both ends or one end of a polyalkylene oxide chain-containing compound can be obtained. And may be used as a mixture.

Among these components (D), those having an alkylene oxide chain of an ethylene oxide chain and a hydroxyl group at one end are the most preferred because of the high anti-staining effect of the present invention, that is, the high anti-staining property and high permeation resistance. preferable.

The mixing ratio of the component (D) is 0.1 to 20 parts by weight, preferably 0.2 to 10 parts by weight, based on 100 parts by weight of the resin solids of the component (A). If the amount is less than 0.1 part by weight, no effect can be seen.
This results in poor compatibility with the resin and poor water resistance of the cured product.

[Curing Accelerator] In the present invention, in addition to various silane coupling agents, aluminum-based, zirconium-based, titanium-based metal alkoxides, metal acylates, metal chelates, and the like can be used as the curing accelerator. . Of these, epoxy group-containing silane coupling agents such as β- (3,4 epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, and γ-glycidoxypropyltriethoxysilane are preferably used. .

The curing accelerator is composed of the resin solid content 1 of the component (A).
0.001 to 20 parts by weight can be added to 00 parts by weight. When the amount is less than 0.001 part by weight, the effect of addition is not observed, and when the amount is more than 20 parts by weight, storage stability tends to decrease.

[Others] In the coating composition of the present invention, the components (A), (B) and (C) (and (D)
In addition to the transparent (clear) coating film which may be added with a component, a coloring pigment may be blended to form a coloring (enamel) coating film. Examples of such coloring pigments include titanium oxide, zinc oxide and carbon. Black, ferric oxide (Bengara),
Inorganic pigments such as lead chromate (molybdate orange), graphite, yellow iron oxide, ocher, ultramarine, cobalt green, etc., azo, naphthol, pyrazolone, anthraquinone, perylene, quinacridone, disazo, iso Organic pigments such as indolinone-based, benzimidazole-based, phthalocyanine-based, and quinophthalone-based pigments can be used.

It is also possible to use extenders such as heavy calcium carbonate, clay, kaolin, talc, precipitated barium sulfate, barium carbonate, white carbon, and diatomaceous earth. In particular, when a matte coating film is formed, it is optimal to use white carbon or diatomaceous earth which least impairs the stain resistance effect on the coating film surface.
When these inorganic substances are added to the paint, it is preferable to treat the powder surface with a coupling agent or to add the coupling agent to the paint.

In the coating composition of the present invention, it is possible to add various additives which can be usually added to the coating so as not to affect the effect of the present invention. Such additives include plasticizers, preservatives, fungicides, anti-algal agents, defoamers,
Leveling agents, pigment dispersants, anti-settling agents, anti-sagging agents,
Matting agents, ultraviolet absorbers and the like.

[Applied Surface / Coating Method] The coating composition of the present invention can be used for surface finishing of various materials such as metal, glass, porcelain tile, concrete, siding board, extruded board, and plastic. It is used to protect buildings such as buildings and civil engineering structures. At this time, the coating composition of the present invention is applied to the final finished surface, and can be applied directly to the base material or applied after some surface treatment (base treatment, etc.). Although it is also possible, there is no particular limitation.

The coating composition of the present invention is prepared by adding various additives to form a coating, and is usually diluted with an aliphatic hydrocarbon-based solvent for coating. As a coating method, for example, various methods such as brush coating, roller coating, spray coating, a roll coater, and a flow coater can be used. In particular, since the composition of the present invention hardly causes sagging, can be coated with a thick film, and has good leveling property, it is highly suitable for brush coating and roller coating.

The composition of the present invention can be suitably used for renovation work because 50% by weight or more of the composition is an aliphatic hydrocarbon. This is because when a paint using a solvent having a strong dissolving power is repainted, a phenomenon called “lifting” of an old paint film occurs, and when an aliphatic hydrocarbon is contained in an amount of 50% by weight or more, such a phenomenon is caused. This is because the lifting phenomenon does not occur.

[0077]

EXAMPLES Examples and comparative examples are shown below to further clarify the features of the present invention.

(Synthesis Example 1) Synthesis Example of Alkoxysilane Compound 1 Weight average molecular weight: 500, average condensation degree: about 4, nonvolatile content: 10
To 100% by weight of 0% methyl silicate (hereinafter referred to as "methyl silicate A"), 44.4 parts by weight of n-butyl alcohol and 0.03 part by weight of dibutyltin dilaurate as a catalyst were added, and after mixing, 75 parts by weight were added. The methanol removal reaction was carried out for 8 hours at
Was synthesized. The transesterification rate of this alkoxysilane compound 1 was about 30%, and the residual silica ratio obtained by calcining at 900 ° C. was 40.7% by weight.

(Synthesis Example 2) Synthesis Example of Alkoxysilane Compound 2 Weight average molecular weight: 1000, average condensation degree: about 8, non-volatile content: 1
100 parts by weight of methyl silicate (hereinafter, referred to as "methyl silicate B") of 5%, 58.0 parts by weight of n-heptyl alcohol and 0. 0% of dibutyltin dilaurate.
03 parts by weight were mixed, and an alkoxysilane compound 2 was synthesized in the same manner as in Synthesis Example 1. The transesterification rate of this alkoxysilane compound 2 was about 27%, and the residual silica ratio was 39.4% by weight.

Synthesis Example 3 Synthesis Example of Alkoxysilane Compound Containing Polyalkylene Oxide Chain Polyethylene glycol 200 (average molecular weight: 200; Wako Pure Chemical Industries, Ltd.) was placed in a reaction vessel equipped with a heating device, stirrer, reflux device, dehydration device, and thermometer. 20 parts by weight), 54.3 parts by weight of Y-9030 (manufactured by Nippon Unicar Co., Ltd.), which is an isocyanate-containing silane, and 0.05 part by weight of dibutyltin dilaurate were charged and reacted at 50 ° C. for 8 hours. Thus, a pale yellow polyethylene oxide chain-containing alkoxysilane compound was obtained. The weight average molecular weight of this alkoxysilane compound having a polyethylene oxide chain was 800 as measured by gel permeation chromatography (hereinafter referred to as GPC) in terms of polystyrene.

(Preparation of paint) Resins as shown in Table 1, Table 2
Using the raw materials shown in Table 3, coating materials were prepared with the formulations shown in Table 3. The following tests were performed using the prepared paint.

[0082]

[Table 1]

[0083]

[Table 2]

[0084]

[Table 3]

(Test Method) Workability / Finishability SK # 10 on a slate plate of 900 × 1800 × 6 mm
00 primer (epoxy resin base coating material, manufactured by SK Chemical Co., Ltd.) is spray-coated so as to have a dry film thickness of 30 μm.
Drying was performed for 16 hours under standard conditions (temperature 20 ° C., humidity 65%). Next, the prepared coating composition was coated at a coating amount of 120 g /
was roller painted in m ^2. Whether or not dripping occurs at this time,
The state of leveling was visually checked. The evaluation was evaluated as ○ when no sagging occurred and the leveling property was good, and x when the sagging occurred or the leveling property was poor.

2. Adhesion 150 x 75 x with phthalic acid resin paint applied in advance
On a 0.8 mm aluminum plate and a 225 × 60 × 10 mm porcelain tile, apply the prepared coating composition to a dry film thickness of 30 μm.
m and spray dried under standard conditions for 168 hours to produce test specimens. The test was performed on the prepared test body in accordance with JIS K5400 8.5.2. The evaluation is as follows. ：: Less than 5% of defective area ○: 5 to 15% of defective area △: 15 to 35% of defective area ×: 35% or more of defective area

3. SK # 100 on 150 × 75 × 0.8mm aluminum plate
The No. 0 primer was spray-coated so as to have a dry film thickness of 30 μm, and was dried under standard conditions for 16 hours. Next, the prepared coating composition was spray-coated so as to have a dry film thickness of 40 μm to prepare a test body. After the prepared test body was dried and cured in a standard state for 12 hours to 168 hours, JISK
5400 8.10 According to the stain resistance test, 1
A 5% by weight aqueous dispersion of carbon black was applied with a diameter of 2
0 mm and a drop of 5 mm in height.
Left for 2 hours. Thereafter, the film was washed in running water, and the degree of contamination of the coating film surface was visually evaluated. The evaluation is as follows. ○: No trace △: There is a trace ×: There is a remarkable trace

4. Specimens were prepared in the same manner as in Weatherability 2. For these, using a super UV tester (manufactured by Iwasaki Electric Co., Ltd.) as an accelerated weathering tester, light irradiation 6 hours, dew condensation 2 hours (total 8 hours)
The test was performed up to 80 cycles with the time being one cycle. The evaluation was performed by measuring the gloss retention after 80 cycles. ：: Gloss retention of 80% or more Δ: Gloss retention of 70 to 80% ×: Gloss retention of less than 70%

[0089]

[Table 4]

(Results) Table 4 shows the results of each test. Examples 1 to 6, which are the compositions of the present invention, showed good results in all the tests. On the other hand, in Comparative Example 1, the resin did not contain an amino group and had a small amount of a silicone component.
The result was also inferior in weather resistance. In Comparative Example 2, since the resin did not contain a silicone component, the resistance to the penetration of dirt at the initial stage was not sufficient, and the result was poor adhesion to the porcelain tile and poor weather resistance. In Comparative Example 3, since the resin did not contain an amino group and a silicone component,
The resistance to the penetration of dirt in the initial stage was not sufficient, resulting in poor adhesion to the porcelain tile and poor weather resistance. Further, Comparative Examples 1 to 3 did not contain the dispersion type resin, so that sagging occurred during coating. In Comparative Examples 4 and 5, since methyl silicate was used as the component (B),
The result was inferior resistance to stain penetration.

[0091]

According to the present invention, it has low odor and low toxicity, has little influence on air pollution, can be applied directly to any substrate, hardly causes sagging in work, and has a relatively thick film. With good leveling properties and excellent aesthetics.
A weak solvent type paint having good dryability and curability after coating, and excellent stain resistance and good long-term weather resistance and stain resistance immediately after coating can be obtained. Furthermore, by adding a polyalkylene oxide chain-containing alkoxysilane compound, the surface of the coating film can be made more hydrophilic, and a paint excellent in stain resistance can be obtained. The composition of the present invention has almost no lifting problem even when it is applied on an existing coating film, and can be suitably used particularly for renovation work.

 ──────────────────────────────────────────────────続 き Continued on front page F-term (reference) 4J038 CG141 CL001 DF012 DG262 DL022 DL032 EA011 GA03 GA09 GA15 JC32

Claims (3)

[Claims] 1. A coating composition in which at least 50% by weight of all solvents in the coating are aliphatic hydrocarbons, comprising (A) a dispersed resin and having an amine value of 0.05 to 5 KOH mg /
g, a synthetic resin having a hydroxyl value of 15 to 100 KOH mg / g and containing a silicone component in a resin solid content of 5 to 30% by weight in terms of SiO 2, (B) a condensate of tetraalkoxysilane having an average condensation degree of 4 to 10 Wherein the alkyl group in the condensate is a mixture of those having 1 to 3 carbon atoms and 4 to 12 carbon atoms, and the mixture ratio is such that the alkyl group having 4 to 12 carbon atoms is contained in the condensate. A compound that is 5 to 50% of all alkyl groups, (C) an isocyanate compound,
With respect to 100 parts by weight of the resin solid content of (A), (B)
1.0 to 50.0 parts by weight in terms of iO2, (C) is NCO
A coating composition, characterized in that it is contained so as to have a / OH ratio of 0.7 to 2.0. 2. The method according to claim 1, wherein (D) the number of repeating units is from 2 to 4.
A polyalkylene oxide chain of 0, an alkoxysilane compound having a weight average molecular weight of 150 to 3500,
The solid content is 0.1 to 20 parts by weight based on 100 parts by weight of the resin solid content of (A).
The coating composition according to any one of the preceding claims. 3. The coating composition according to claim 1, wherein 30% by weight or more of the total resin solid content is a dispersion type resin.