JP3511527B2 - Composition for coating - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to coating compositions. More specifically, it relates to a coating composition capable of forming a coating film having improved adhesion of a urethane resin coating material to a metal such as iron and improved surface hardness and stain resistance.

[0002]

2. Description of the Related Art Conventionally, various coating compositions containing a silicon compound have been investigated for the purpose of improving scratch resistance. For example, as a method using an alkoxysilane hydrolyzate, Japanese Patent Laid-Open Nos. 53-2565 and 56-56 are available.
22365, JP-A-61-166824 and the like. Further, as a coating composition containing organoalkoxysilane and colloidal silica or colloidal alumina as main components, JP-B-52-39691 and JP-B-5
3-5042, JP-A-54-87736, JP-A-55-
94971, JP-A-56-99236, JP-A-59-6.
It is proposed in Japanese Patent No. 8377. Furthermore, coating compositions using an acrylic copolymer containing an alkoxysilyl group are disclosed in JP-A-3-47871 and JP-A-3-3787.
It is proposed in Japanese Patent Laid-Open No. 54278. Furthermore, in order to exert the respective characteristics of both, it has been noted that a composition obtained by mixing the above-mentioned hydrolyzate of alkoxysilane and an acrylic copolymer is used for coating.

[0003]

However, with the coating composition comprising the above mixture, there is room for improvement in the transparency and boiling water resistance of the resulting coating film. The composition obtained by copolymerizing a (meth) acrylic acid alkyl ester and a hydroxyl group-containing (meth) acrylic acid ester in the presence of a silicate oligomer is used for the surface of metals such as iron, plastics, wood, and concrete. It was found that it was possible to form a coating film having good transparency and boiling water resistance, and that the composition also had scratch resistance, heat resistance, weather resistance, and adhesion, which are inherent to the composition. went. The Applicant has conducted extensive studies to further develop new uses of this composition.

[0004]

[Means for Solving the Problems] In order to solve the above problems, as a result of extensive studies, it was found that a composition obtained by coexisting a specific silicate oligomer at the time of polymerization of an alkoxysilyl group-containing ethylenically unsaturated monomer The inventors have found that the physical properties of a coating film can be improved by mixing a urethane resin, and have reached the present invention. That is, the present invention, in the presence of a silicate oligomer represented by the following general formula [I] in an organic solvent, a composition obtained by polymerizing an alkoxysilyl group-containing ethylenically unsaturated monomer, and a urethane resin , Ure
The composition co-polymerized with 100 parts by weight of the tongue resin is solidified.
The coating composition is characterized by mixing 5 to 50 parts by weight in terms of form .

[Chemical 1] (In the formula, n is an integer of 1 to 20, R is hydrogen or a carbon number of 1 to
4 represents an alkyl group or a phenyl group)

The present invention will be described in detail below. The silicate oligomer used in the present invention is not particularly limited as long as it is represented by the following general formula [I].

[Chemical 1] (In the formula, n is an integer of 1 to 20, R is hydrogen or a carbon number of 1 to
4 represents an alkyl group or a phenyl group)

The silicate oligomer can be obtained, for example, by hydrolyzing tetraalkoxysilane or tetraphenoxysilane such as tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane and tetrabutoxysilane. n can be adjusted by controlling the hydrolysis rate in this case

The hydrolysis reaction itself can be carried out by a known method. For example, a predetermined amount of water is added to the above tetraalkoxysilane in the presence of an acid catalyst to distill off the alcohol by-produced, usually at room temperature. The reaction is performed at about -100 ° C. The alkoxysilane is hydrolyzed by this reaction, and a liquid silicate oligomer having two or more hydroxyl groups by a condensation reaction (usually an average degree of polymerization of about 2 to 8,
Preferably 3-6) is obtained as a hydrolyzate. The degree of hydrolysis can be appropriately adjusted depending on the amount of water used, but in view of the physical properties of the coating composition or the curing of the coating film, it is usually 40 to 90 in the present invention.
%, Preferably about 60 to 80%. When it is more than the above range, the adhesiveness is lowered, and when it is less than the above range, n is 0.

The tetraalkoxysilicate oligomer thus obtained usually contains about 2 to 10% of a monomer. If this monomer is contained, the storage stability of the coating composition is lacking, the viscosity increases during storage, and it becomes difficult to form a thin film. Therefore, the monomer content should be 1% or less, preferably 0.3% or less. This monomer removal is carried out by flash distillation and vacuum distillation so that

The amount of the silicate oligomer used during the co-polymerization is the alkoxysilyl group-containing ethylenically unsaturated monomer 1
5 to 500 parts by weight, preferably 10 to 100 parts by weight
˜400 parts by weight, particularly preferably 10 to 300 parts by weight. If it is less than this, the hardness of the coating film is remarkably lowered, and if it is more than this, the adhesion to the substrate is remarkably lowered. Incidentally, when the amount of the alkoxysilyl group-containing ethylenically unsaturated monomer in the above range is large, alkali resistance and storage stability are improved, and when the content of the silicate oligomer is large, hardness, solvent resistance,
Weather resistance and adhesion tend to improve.

The alkoxysilyl group-containing ethylenically unsaturated monomer used in the present invention means γ- (meth) acryloxypropyltrimethoxysilane, γ- (meth) acryloxypropyltriethoxysilane, γ- (meth). Acryloxydimethyldimethoxysilane, γ- (meth) acryloxytrimethoxysisilane, γ- (meth) acryloxytriethoxysisilane, vinyltriethoxysilane, vinyltripropoxysilane, vinylmethyldiethoxysilane, vinyltri (ethoxymethoxy) ) Silane, allyltrimethoxysilane, P-vinylphenyltrimethoxysilane and the like. Among them, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, vinyltriethoxysilane and the like are preferably used.

In the co-polymerization, an alkoxysilyl group-containing ethylenically unsaturated monomer may be used alone, but a copolymerization with (meth) acrylic acid alkyl ester and / or a carboxyl group-containing unsaturated monomer is also possible. is there. The number of carbon atoms of the alkyl group of the (meth) acrylic acid alkyl ester is not particularly limited and any one of about 1 to 20 can be used, but the number of carbon atoms of the alkyl group is 1 to 3 and the number of carbon atoms of the alkyl group. It is preferable to use it in combination with a material having a ratio of 4 or more from the viewpoint of the balance of physical properties of the coating film. (A) Alkyl group-containing (meth) acrylic acid alkyl esters having 1 to 3 carbon atoms include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate and the like. Are used alone or in combination of two or more.

Examples of the (b) alkyl ester of (meth) acrylic acid having 4 or more carbon atoms in the alkyl group include butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, and (meth) acrylate. ) Acrylic acid t
-Butyl, amyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, (meth)
Examples thereof include octyl acrylate, 2-ethylhexyl (meth) acrylate, decyl (meth) acrylate, lauryl (meth) acrylate, and stearyl (meth) acrylate, which may be used alone or in combination of two or more. As a polyvalent monomer other than the above, aromatic monomers such as styrene and vinyltoluene, vinyl compounds such as vinyl acetate and vinyl propionate, and the like are used in combination, if necessary.

Alkoxysilyl-based ethylenically unsaturated monomer and (meth) acrylic acid alkyl ester and /
Or when used in combination with a carboxyl group-containing unsaturated monomer,
The ratio of the alkoxysilyl group-containing ethylenic unsaturated monomer in the total amount of 100 parts by weight of the monomer is 1 to 30% by weight, the ratio of the (meth) acrylic acid alkyl ester and / or the carboxyl group-containing unsaturated monomer. Is advantageously between 70 and 99% by weight. In addition, in the (meth) acrylic acid alkyl ester, an alkyl group (meth) acrylic acid alkyl ester (a) having 1 to 3 carbon atoms and an alkyl group (meth) acrylic acid alkyl ester (b) having 4 or more carbon atoms are included. The ratio of (a) / (b) is 2/8 by weight
8/8, preferably 3/7 to 7/3 is desirable.

By using such a monomer, the crosslinkability with the silicate oligomer is improved. Also, when the coating film is cured, it contracts, internal stress may occur, and problems such as cracks may occur, but to avoid this,
It is preferable to set the glass transition point low depending on the composition ratio of the polymer. A specific temperature range of a suitable glass transition point (Tg) is −20 to 60 ° C.

The method of such coexisting polymerization is not particularly limited, but it can be produced, for example, by mixing each component and by a usual radical polymerization method. The organic solvent used in the present invention is not particularly limited, and those capable of dissolving the raw material monomer and polymer and the silicate oligomer can be used, and can be appropriately selected depending on the substrate to be coated or the coating method. Specifically showing the organic solvent that can be used,
Methanol, ethanol, isopropyl alcohol, n
-Alcohols such as butanol and octanol, ethylene glycol, ethylene glycol monomethyl ether,
Glycol derivatives such as ethylene glycol monoethyl ether, ethylene glycol mono n-propyl ether and ethylene glycol mono n-butyl ether, hydrocarbons such as benzene, kerosene, toluene and xylene, methyl acetate, ethyl acetate, butyl acetate and methyl acetoacetate,
Examples thereof include esters such as ethyl acetoacetate, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and acetylacetone, and ethers such as ethyl ether, butyl ether, methyl cellosolve, ethyl cellosolve, dioxane, furan and tetrahydrofuran.
These organic solvents can be used either individually or in combination.

The amount of the solvent used is 20 to 2 with respect to 100 parts by weight of the total amount of the monomer and the silicate oligomer.
It is possible in the range of 00 parts by weight. This composition ratio can be appropriately selected according to the purpose of use. If the amount is less than the above range, there may occur problems during coating, such as difficulty in obtaining a uniform coating film.

As the polymerization catalyst, known radical polymerization catalysts such as azobisisobutyronitrile, benzoyl peroxide, ditertiary butyl peroxide,
Cumene hydroperoxide and the like are used. A suitable temperature for the polymerization is 60 to 150 ° C., and a practical polymerization time is about 6 to 20 hours. The composition of the present invention is
As described above, the organic solvent used at the time of polymerization can be put to practical use as a coating material in the state of being used as it is, but if necessary, it may be used by substituting it with an arbitrary solvent.

The urethane resin used in the present invention may be any of those known for paints. That is, a polyester polyol or a polyether polyol is reacted with a polyvalent isocyanate. Polyester polyol is a reaction product of dicarboxylic acid and diol, and as dicarboxylic acid, aliphatic dibasic acids such as succinic acid, adipic acid, azelaic acid and sebacic acid,
Examples thereof include phthalic acid, tetrahydro (anhydrous) phthalic acid, and hexahydro (anhydrous) phthalic acid. Examples of the diol include ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, 1,4-
Examples thereof include butanediol, 1,6-hexanediol, neopentyl glycol and the like. Among them, adipic acid as a dicarboxylic acid and a combination of 1,4-butanediol and ethylene glycol as a diol are preferable. A molecular weight of about 500 to 3,000 is suitable, and the adjustment is performed by adjusting the type of dicarboxylic acid and diol and the hydroxyl value (K
OHmg / g) and the hydroxyl value is approximately 2
It is in the range of 5-250 (KOHmg / g).

The polyether polyol is a polymer obtained by addition reaction of alkylene oxide with various dihydric alcohols as described above. The ratio of (A) and (B) at the time of reacting the polyester polyol or polyether polyol with the (B) polyisocyanate compound is (A) / (B) = 1/1 to 2/1 (mol), In other words, the ratio of the number of hydroxyl groups in (A) and the number of isocyanate groups in (B) is in the range of 1 to 2. Isocyanate groups can also be present in the chain of component (A) as a chain extender of component (A). The (B) polyvalent isocyanate compound is a compound having at least two isocyanate groups in one molecule, and specifically, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, m-xylylene diisocyanate. Isocyanate,
Examples thereof include P-xylylene diisocyanate, diphenylmethane 4,4 ′ diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, lysine diisocyanate, modified diisocyanates thereof, hydrogenated diisocyanate, etc. These may be used alone or in combination of two or more.

The mixing ratio of the urethane resin and the co-polymerization composition is such that the acrylic resin and the silicate oligomer in the composition are mixed.
The composition ratio is 5 to 50 parts by weight based on 100 parts by weight of the urethane resin in terms of solid content, although there is some variation in the composition ratio. If it is 5 parts by weight or less, the effect of improving the physical properties of the urethane resin is poor, and if it is 50 parts by weight or more, the compatibility tends to be poor.

Further, it is desirable to use a curing catalyst in the coating composition of the present invention thus obtained. The curing catalyst should be added before use (two-pack type)
It is also possible to store in the state of being added from the beginning (one-pack type). Specific examples of the curing catalyst include hydrochloric acid, nitric acid, phosphoric acid, inorganic acids such as boric acid, acetic acid, formic acid, maleic acid, phthalic acid, benzoic acid, organic acids such as paratoluenesulfonic acid, dibutyltin laurylate, dibutyltin octoate, Dibutyltin acetate, organotin compounds such as dioctyltin laurate, tetrabutyl titanate, tetrapropyl titanate, organotitanium compounds such as tetrabutoxy titanate, monomethyl phosphate, phosphate esters such as monoethyl phosphate, γ
-Aminopropyltrimethoxysilane, N-β-aminoethyl-γ-aminopropyltrimethoxysilane, γ-
There are silane coupling agents such as ureidopropyltriethoxysilane.

In addition, organoaluminum compounds such as tris (acetylacetonato) aluminum and tris (ethylacetoacetate) aluminum, tetrabutylzirconate, organozirconium such as butoxytris (acetylacetonato) zirconium, ethylenediamine, diethylenetriamine, piperazine , Amines such as metaphenylenediamine, diethanolamine and triethanolamine, alkali compounds such as sodium hydroxide and potassium hydroxide, and epoxy compounds.
Inorganic acids, organic tin compounds, organic acids and organic aluminum compounds are particularly preferable. The amount of these catalysts used varies depending on the catalyst, but when hydrochloric acid is used, it is preferably about 0.1 to 2 parts by weight with respect to 100 parts by weight of the silicate oligomer.

The method of using the coating composition of the present invention will be described more specifically. The above-mentioned co-polymerized (meth) acrylic copolymer composition is usually adjusted in concentration, then a curing catalyst is added and further mixed with a urethane resin, and then coated on a substrate and dried by heating. When R of the silicate oligomer is an alkyl group or a phenyl group, it may be hydrolyzed if necessary. In this case, the base material can be applied to iron, stainless steel, aluminum, other metals, alloys, plastics, wood, cement, concrete and the like. Examples of the coating method include brush coating, spin coating, spray coating, depping, roll coating, and gravure printing. The film thickness at this time is preferably 0.1 to 200 μm, more preferably 1 to 100 μm. The composition of the present invention is particularly effective for thickening the coating film, and the conventional one has 5
If it exceeds 0 μm, cracks and the like are likely to occur, but in the present invention, it is possible to increase the film thickness. When it is thinner than the above range, it is difficult to obtain sufficient scratch resistance,
On the other hand, if it is thicker than the above range, cracks may occur, which is not preferable.

When preparing a coating composition using the composition of the present invention, a dehydrating agent or an alkyl alcohol having 1 to 10 carbon atoms in the alkyl group may be added, if necessary, in consideration of the stability of the coating composition. You can also The dehydrating agent in this case, trimethyl orthoformate, triethyl orthoformate, tripropyl orthoformate, trimethyl orthoacetate, triethyl orthoacetate, tripropyl orthoacetate, trimethyl orthopropionate, triethyl orthopropionate,
Orthocarboxylic acid esters such as trimethyl orthoisopropionate, triethyl orthoisopropionate, trimethyl orthobutyrate, triethyl orthobutyrate, trimethyl orthoisobutyrate, and triethyl orthoisobutyrate are used, and the addition amount thereof is a (meth) acrylic copolymer 0 to 30 parts by weight, preferably 0.
5 to 30 parts by weight, particularly preferably 5 to 25 parts by weight.

Further, as pigments used in the paint, white pigments such as titanium oxide, calcium carbonate, talc, lithobon, barium sulfate, calcium sulfate, alumina, clay, etc., black pigments such as carbon black, iron black etc., phthalocyanine blue, Blue pigments such as navy blue and ultramarine blue, yellow pigments such as lake yellow, yellow lead, oak yellow and Hansa yellow, red pigments such as red iron oxide and lake red, orange pigments such as chrome vermillion, green pigments such as phthalocyanine green and chromium oxide. And so on.

Further, other additives for resins can be added to the composition of the present invention as long as the curing of the invention is not impaired. For example, ultraviolet stabilizer, antioxidant, antistatic agent, conductivity imparting agent, scratch resistance imparting agent, compatibilizer, adhesiveness imparting agent, colorant, fluidity improving agent, plasticizer, anti-sagging agent, precipitation Examples include an inhibitor and an antifoaming agent. A sand mill, a disper, a ball mill and the like which are usually used are used for preparing the paint. This paint can be used as a top coat paint for exterior materials such as concrete, mortar buildings, roof tiles, and siding boards, and also as a paint for interiors and floors of buildings, and in particular, it has excellent weather resistance in exterior applications. It can be used as paint.

[0027]

In the present invention, a coating composition which gives a urethane resin-based coating film having improved adhesion to metals such as iron and improved surface hardness and stain resistance is obtained.

[0028]

The present invention will be described in more detail based on the following examples and comparative examples, but the invention is not limited to the following examples as long as the gist thereof is not exceeded. The coating film was evaluated by the following methods. (1) Metal Adhesion (Peeling Cellotape): In order to evaluate the adhesive strength of the coating film, 11 parallel and 11 horizontal and vertical lines perpendicular to the center of the coating film were drawn at intervals of 1 mm until reaching the substrate surface, and 1 cm. ^I added a grid to make 100 squares in ² . A cellophane adhesive tape (trade name: “Cellotape” made by Nichiban) was strongly adhered on the cross of the grid, and the number of squares without peeling was measured when the tape was rapidly peeled in the direction of 90 degrees.

(2) Pencil hardness: The degree of scratches is measured according to JIS K
It was evaluated by a pencil hardness test according to 5400. (3) Contamination resistance: A red and black quick-drying oil-based ink available on the market was used to draw a line, and the film was allowed to stand at room temperature for 24 hours and then ethanol-coated.
When there was no trace of the wiping line, it was evaluated as ○, when the trace of the line remained slightly was evaluated as △, and when the trace of the line remained clearly as ×.

[Preparation of Silicate Oligomer] Silicate Oligomer A 500 equipped with stirrer, reflux condenser and thermometer
Tetramethoxysilane 2 was added to a 3 ml round bottom flask.
After adding 34 g and 74 g of methanol and mixing, 0.0
22.2 g of 5% hydrochloric acid was added, and a hydrolysis reaction was carried out at an internal temperature of 65 ° C. for 2 hours. Next, the condenser was replaced with an extraction tube, the internal temperature was raised to 150 ° C., the mixture was extracted with methanol and further heated at 150 ° C. for 3 hours to condense to obtain a hydrolyzate. The degree of polymerization was 3 to 6 and the hydroxyl group was 10 or more. The amount of monomers in the tetramethoxysilane oligomer was 5%.

Silicate Oligomer B Following the above, the tetramethoxysilane oligomer is boiled with a jacket heated to 100 to 150 ° C., and the vaporized monomer is discharged out of the system together with an inert gas. The amount of monomers in the tetramethoxysilane oligomer thus obtained was 0.2%. Silicate Oligomer C Tetraethoxysilane is used instead of the above tetramethoxysilane, and the amount of monomers in the oligomer is 0.3% or less. Tetraethoxysilane oligomer (degree of polymerization 3 to 6)
Got

[Production of Coexisting Polymerization Composition] Composition 1 100 parts by weight of γ-methacryloxypropyltrimethoxysilane and 550 parts by weight of methyl methacrylate were placed in a flask equipped with a nitrogen inlet tube, a reflux condenser, a thermometer and a stirrer. Parts, n-butyl acrylate 350 parts by weight, silicate oligomers A to C 500 parts by weight (in terms of pure content) and xylene 420 parts by weight, isopropyl alcohol 80
1 part by weight, 2 parts by weight of benzoyl peroxide were charged,
Polymerization was initiated by heating to 90 ° C. Two hours after the initiation of the polymerization, the polymerization was continued for 10 hours while adding a solution of 8 parts by weight of benzoyl peroxide in 30 parts by weight of xylene. Resin content 72% by weight, viscosity 2000 cps (25 ° C)
A co-polymerized product of Tg was 20 ° C. To the above co-polymerized product, 600 parts by weight of xylene was added to make the resin content 54% by weight. To this solution was added 0.95 g of 1N hydrochloric acid and the temperature was 65 ° C.
Stir for 30 minutes. Add this solution to a glass plate (70 mm x 1
50 mm x 0.5 mm) was applied with an applicator, and then heat-treated at 110 ° C for 30 minutes. This coating (1
The physical properties of 00 μ) were evaluated by the above methods, and the results are shown in Table 1.

Composition 2 In accordance with the above, 200 parts by weight of γ-methacryloxypropyltrimethoxysilane, 400 parts by weight of methyl methacrylate, 250 parts by weight of n-butyl acrylate, 15 parts of styrene.
Co-polymerization composition consisting of 0 parts by weight (Tg 40 ° C.)
Got

Composition 3 In accordance with the above, 50 parts by weight of γ-methacryloxypropyltriethoxysilane, 400 parts by weight of methyl methacrylate, 450 parts by weight of n-butyl acrylate, styrene 11
A co-polymerization composition (Tg 8 ° C.) having a composition of 0 part by weight was obtained.

[Production of Urethane Resin] Resin a: A flask equipped with a stirrer and a reflux condenser was charged with 1 mol of adipic acid and 1.25 mol of ethylene glycol at 220 ° C.
Was reacted until the hydroxyl value reached 112 mgKOH / g to obtain a polyol having a molecular weight of 1000. Then isophorone diisocyanate was added to ethylene glycol in 1.
A urethane resin was produced by a 2-fold molar reaction.

Resin b In the same manner, urethane resin was obtained by using polytetramethylene glycol (molecular weight 1000) as the polyol. Resin c In the same manner, a urethane resin was obtained by using polyoxypropylene glycol (molecular weight 1000) as a polyol.

Examples 1 to 5 A coexisting polymerization composition and a urethane resin were mixed. This solution was applied to a SUS plate (70 mm × 150 mm × 0.5 mm) using an applicator, and then heat treated at 110 ° C. for 30 minutes. The physical properties of this coating film (100 μ) were evaluated by the methods described above, and the results are shown in Tables 1 and 2.

Examples 6 to 7 In Example 2, the amount of silicate oligomer used was 1
000 parts by weight (Example 5) and 1500 parts by weight (Example 6). The results are shown in Tables 1 and 2. Example 8 The same operation as in Example 2 was performed except that dibutyltin dilaurate was used instead of hydrochloric acid. The results are shown in Table 1 and Table 2.
It was shown to.

Example 9 The same operation as in Example 2 was performed except that tris (acetylacetate) aluminum was used instead of hydrochloric acid. The results are shown in Tables 1 and 2. Control Example 1 In Example 2, the use of the coexisting polymerization composition was omitted. The results are also shown in Tables 1 and 2.

[0040]

[Table 1] Urethane resin co-polymerization composition type usage amount composition type oligomer type usage amount Example 1 Resin a 100 1 A 20 〃 2 〃 〃 1 〃 3 〃 1 〃 1 C 〃 4 Resin b 30 〃 2 B 〃 5 resin c 〃 3 B 40 〃 6 resin a 〃 1 B 20 〃 7 〃 〃 1 B 〃 〃 8 〃 〃 1 〃 1 〃 1 〃 1 〃 1 〃 1 〃

[0041]

[Table 2] Metal adhesion Pencil hardness Stain resistance Example 1 100/100 H ○ 〃2〃H ○ 〃3〃H ○ 〃4〃H ○ 〃5〃2H ○ 〃6〃H ○ 〃7〃H ○ 〃 8 〃 H ○ 〃 9 〃 H ○ Comparative example 1 〃 F ×

[0042]

EFFECT OF THE INVENTION The coating composition of the present invention can form a coating film which has high adhesion to each substrate, especially metal, sufficient hardness, and excellent stain resistance.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI C09D 133/06 C09D 133/06 143/04 143/04 183/04 183/04 (58) Fields investigated (Int.Cl. ⁷ , DB name) C09D 1/00-10/00 C09D 101/00-201/10

Claims (4)

(57) [Claims] 1. A composition obtained by polymerizing an alkoxysilyl group-containing ethylenically unsaturated monomer in the presence of a silicate oligomer represented by the following general formula [I] in an organic solvent, and a urethane resin : For 100 parts by weight of urethane resin
A coating composition, characterized in that 5 to 50 parts by weight of the composition obtained by co-polymerization are mixed in terms of solid content . [Chemical 1] (In the formula, n is an integer of 1 to 20, R is hydrogen or a carbon number of 1 to
4 represents an alkyl group or a phenyl group) 2. Alkoxysilyl group-containing ethylenically unsaturated monomer is used together with alkoxysilyl group-containing ethylenically unsaturated monomer during coexisting polymerization, and alkoxysilyl group-containing ethylenic unsaturation is used in 100 parts by weight of the total amount of the monomers. ratio is 1 to 30 wt% of the monomers, according to claim 1, acrylic acid alkyl esters, characterized in that 70 to 99 wt%
The composition as described. 3., characterized by using a tetramethoxysilane partial hydrolyzate as silicate oligomer according to claim 1 or 2 composition. 4. A tetramethoxysilane partial hydrolyzate as silicate oligomer claims 1-3 monomer amount is characterized by the use of those of 1 wt%
The composition according to any one of claims.