JP2932766B2 - Coating method of hardened cementitious material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for coating a surface of a hardened cementitious material, and more particularly, to a method of applying a composition to the surface of a hardened cementitious material and curing the composition by heating or high-energy radiation. The present invention relates to a method for forming a coating film having glaze-like gloss and having excellent hardness, surface damage resistance, water resistance, and durability.

[0002]

2. Description of the Related Art Hardened cementitious materials are widely used as building materials, and the surface thereof is generally coated with various paints for the purpose of design, waterproofing, and durability. At that time, it is considered that it is desirable to apply glaze used to obtain tile-like gloss to the surface of the cementitious cured body and bake and integrate it in all aspects of aesthetics, gloss, hardness, water resistance, weather resistance I have.

However, since the glaze needs to be heated to a high temperature of 500 ° C. or more for baking, the cementitious hardened material does not lose water of crystallization at around 330 ° C., has a fragile structure, and is accompanied by a large shrinkage. , Cracks occur.
On the other hand, organic polymer-based paints are excellent in appearance, but have defects in durability and are insufficient in hardness. It is known that these disadvantages of organic polymer-based coatings can be considerably improved by increasing the crosslink density by heat curing.
However, since the cementitious cured product has a high moisture content,
Unless adjusted to a completely dry state, the occurrence of coating bulging, cracks, and the like due to evaporation of water during heat curing is inevitable. In the case of large-sized members, this drying step requires preparation of a huge apparatus, which is impractical. In addition, since organic polymer-based paints usually have poor durability, they need to be repainted every certain months, and the maintenance costs are large.

It is known that organic pigments for coloring paints and cured products themselves are inferior in durability and easily discolored. However, inorganic pigments having excellent durability, on the other hand, have drawbacks in that the coloring is not clear and only a dull color tone can be exhibited.

[0005]

SUMMARY OF THE INVENTION The present invention is intended to solve these problems in organic polymer paints and pigments that can replace inorganic paints such as glazes. It is an object of the present invention to provide a method for forming a coating film having a high glossiness and improved in hardness, abrasion resistance, water resistance, weather resistance and the like.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above object, and have found that an alkyl group having 1 to 3 carbon atoms, a phenyl group and a specific acrylic functional group have been added to the side chain. After applying a composition comprising a polyorganosilsesquioxane, a specific poly (meth) acrylate, and a polymerization initiator to a surface of a cementitious cured product,
High gloss, hardness, surface damage resistance, water resistance by heating to ~ 90 ° C or by irradiating with high energy radiation to cure, and by performing electron beam irradiation without using a polymerization initiator. It has been found that a coating film having excellent properties and durability is formed. That is, the present invention
(A) (meth) acryl-functional polyorganosilsesquioxane represented by the following general formula (I)

Embedded image (Wherein R ₁ and R ₂ represent an alkyl group having 1 to 3 carbon atoms, a phenyl group, an acryl represented by the following general formula (II) and / or
Or, it contains a methacryl functional group, and each of the m structural units is the same or different. R ₃ , R ₄ , R ₅ , and R ₆ are each composed of two or more selected from the group consisting of a hydrogen atom, a methyl group, and an ethyl group, and the hydrogen atom is always included. m indicates the degree of polymerization. The general formula (II) is Wherein R ₇ represents a hydrogen atom or a methyl group, R ₈ is a substituted or unsubstituted divalent hydrocarbon having 1 to 12 carbon atoms, R _7,
R ₈ may be different among m structural units. (B) a poly (meth) acrylate represented by the following general formula (III)

Embedded image (Wherein R ₉ is a hydrogen atom or a methyl group, and one R
₉ may all not be the same. R ₁₀ is a polyvalent hydrocarbon residue having a (meth) acrylic acid residue bonded to a different carbon atom, a polyvalent hydrocarbon residue having oxygen in the main chain, or a polyhydric alcohol and a polybasic acid Represents a residue of an ester, and 1 is an integer of 2 or more. ) And (C) a composition comprising a polymerization initiator, which is applied to the surface of a cementitious cured product, and is heated to 40 to 90 ° C. or irradiated with high-energy radiation to be cured. A method for coating a cured product, a method for coating a cured cementitious product, comprising coating and curing the above-mentioned curable composition after polishing the surface of a cured cementitious product containing an inorganic pigment, and the component (C). The present invention relates to a method for coating a hardened cementitious material, wherein the method comprises irradiating an electron beam without containing the same.

Hereinafter, the present invention will be described in detail. The (meth) acryl-functional polyorganosilsesquioxane used as the component (A) in the present invention is represented by the following general formula (I) and comprises m repeating structural units of silsesquioxane units. It is.

Embedded image R ₁ and R ₂ in the repeating structural unit have 1 to 3 carbon atoms.
Alkyl group, phenyl group and general formula (II) Consisting of acrylic and / or methacrylic functional groups represented by

[0008] The acrylic and / or methacrylic functional groups referred to herein include those containing an acrylic and / or methacrylic group as a part of the functional groups. In addition, carbon number 1
The alkyl group 3 is any one of a methyl group, an ethyl group, a propyl group, and an isopropyl group, and does not include these alkyl groups. If the alkyl group has 4 or more carbon atoms, the hardness and abrasion resistance of the cured film become insufficient. In addition, if there is no phenyl group, the toughness, crack resistance and impact resistance of the cured film become poor, which is not preferable. In the acrylic and / or methacrylic functional group represented by the general formula (II), R ₇ is a hydrogen atom or a methyl group, and R ₈ is an unsubstituted or substituted divalent hydrocarbon group having 1 to 12 carbon atoms. is there. Examples of unsubstituted divalent hydrocarbon group R ₈ include methylene, ethylene, trimethylene, include alkylene groups such as tetramethylene, and the alkyl group and examples of the substituent of the substituted divalent hydrocarbon group R ₈ , An alkenyl group, an aryl group, a cycloalkyl group, or a group in which a part of a hydrogen atom bonded to a carbon atom of these groups is substituted with a halogen atom, a cyano group, or the like.

The respective silsesquioxane units forming the repeating unit of the general formula (I) are determined by the selection of R ₁ and R ₂ , but may be the same or different. R ₁ and R ₂ of the m repeating units of the general formula (I) are an alkyl group having 1 to 3 carbon atoms, a phenyl group and the general formula (I)
It consists of an acrylic and / or methacrylic functional group represented by I), and the molar ratio of the functional substituent, the alkyl group and the phenyl group is preferably from 5 to 50:95 to 50. 5 mol% of acrylic and / or methacrylic functional substituents
If it is less than 50%, the curing rate is low. If it exceeds 50 mol%, the curability is good, but the hardness, abrasion resistance, heat resistance, water resistance and the like are lacking. The molar ratio between the alkyl group of R ₁ and R ₂ and the phenyl group is preferably 99: 1 to 70:30,
When the alkyl group exceeds 99%, adhesion, water resistance and solvent resistance are poor, and when the phenyl group exceeds 30%, hardness and curability are poor.

Next, in the general formula (I), R ₃ , R ₄ ,
R ₅ and R ₆ are composed of two or more selected from a hydrogen atom, a methyl group and an ethyl group, but always include a hydrogen atom. That is, the terminal groups OR ₃ , OR ₄ , OR ₅ , OR _{6 of} the polymer
At least one is a hydroxyl group, and the other is a methoxy group and / or an ethoxy group.

The contents of R ₃ , R ₄ , R ₅ , and R ₆ are affected by the types and ratios of a plurality of trialkoxys used as raw materials, and the reaction conditions such as reactivity to hydrolysis and condensation reactions, reaction temperature and time. Is done. For example, when trimethoxysilane and triethoxysilane are used together in a certain ratio as a raw material, the reactivity to hydrolysis and condensation reaction is higher for methoxysilane, and the reaction is stopped in a state where the condensation reaction has progressed to a certain stage, Of the terminal groups of the general formula (I) used as the component (A) of the present invention, when hydroxyl groups are excluded, the residual ratio of ethoxy groups is higher than the residual ratio of methoxy groups.
The ratio of ethoxy groups is higher than the ratio in the raw material stage. As described herein, the alkoxy group is hydrolyzed into a hydroxyl group, and the subsequent condensation reaction proceeds while taking the form of a dehydration reaction between the hydroxyl groups or a dealcoholation reaction between the hydroxyl group and the alkoxy group. Obviously, it is essential that is always contained in the oligomer of (I).

The number average molecular weight of the component (A) is determined by gel permeation chromatography (hereinafter abbreviated as GPC).
Is easily measured by a measuring method such as
A range of 100,000 is preferred. Molecular weight 1,000
If the molecular weight is less than 100,000, the viscosity of the composition becomes too high, and the viscosity of the composition becomes too high. It becomes difficult to coat a thin film on the body surface. By making the component (A) a polymer having such a molecular weight range, shrinkage of the cured film is reduced, and it is possible to avoid adverse effects such as cracks.

As a method for synthesizing the component (A), there is the following method. If necessary, a trialkoxysilane having an acryl and / or methacryl functional group, an alkyltrialkoxysilane having an alkyl group having 1 to 3 carbon atoms, and a phenyltrialkoxysilane having a phenyl group are added in the presence of water and an acid or a base, if necessary. After heating and condensing, it is produced by removing coexisting water and by-product alcohol. Here, the component (A) can be synthesized by performing hydrolysis and condensation using trichlorosilane instead of trialkoxysilane.

The component (B) is a polyacrylate or polymethacrylate represented by the following general formula:

Embedded image (III) In the formula, R ₉ is a hydrogen atom or a methyl group, and all 1 R ₉ may not be the same. R ₁₀ is a polyvalent hydrocarbon residue having a (meth) acrylic acid residue bonded to a different carbon atom, a polyvalent hydrocarbon residue having oxygen in the main chain, or a polyhydric alcohol and a polybasic acid Represents a residue of an ester, and 1 is an integer of 2 or more.

In this case, a polyvalent hydrocarbon residue in which a (meth) acrylic acid residue is bonded to different carbon atoms of R ₁₀ , or
Polyacrylate or polymethacrylate which is a polyvalent hydrocarbon residue having oxygen in the main chain can be produced by reacting an esterification reaction between an organic polyhydric alcohol and acrylic acid or methacrylic acid under known conditions. it can.

As the organic polyhydric alcohol, ethylene glycol, diethylene glycol, 2,2,4-
Trimethyl-1,3-pentanediol, dipropylene glycol, propylene glycol, average molecular weight of about 15
Polypropylene glycol having from 0 to about 600, triethylene glycol, 1,4-cyclohexanedimethanol, neopentyl glycol, 2,2-dimethyl-3
-Hydroxypropyl, 2,2-dimethyl-3-hydroxypropanate, polyethylene glycol having an average molecular weight of about 150 to about 600, 2,2-bis [4- (2
-Hydroxyethoxy) phenyl] propane, 2,2-
Bis [4- (2-hydroxypropoxy) phenyl] propane, triethanolamine, 2,3-butanediol, tetraethylene glycol, 2,2-bis (4-hydroxyphenyl) propane, glycerin, trimethylolpropane, 1, 4-butanediol, a polycaprolactone ester of trimethylolpropane containing about 1.5 equivalents of caprolactone, a polycaprolactone ester of trimethylolpropane containing about 3.6 equivalents of caprolactone, 2-ethyl-1,3-hexanediol,
1,5-pentanediol, tripropylene glycol, 2,2-bis (4-hydroxycyclohexyl) propane, 1,2,6-hexanetriol, 1,3-propanediol, 1,6-hexanediol, and the like. , One or more of these may be used.

The polyacrylate or polymethacrylate is not particularly limited, but
Examples thereof include diethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, tetraethylene glycol diacrylate, diethylene glycol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, and trimethylolpropane trimethacrylate.

[0018] In the case of obtaining a polyacrylate or polymethacrylate having a residue of an ester composed of a polyhydric alcohol and a polybasic acid as R _10, polyhydric alcohols, such as ethylene glycol, 1,2-propylene Glycol, 1,6-hexanediol, glycerin, trimethylolpropane, 1,2,6-hexanetriol, sorbitol, pentaerythritol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol and the like. .

On the other hand, polybasic acids include, for example, phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, isophthalic acid, terephthalic acid, hymic acid, succinic acid,
Examples include polybasic acids such as adipic acid, dodecanoic acid, sebacic acid, maleic acid, itaconic acid, fumaric acid, pyromellitic acid and trimellitic acid or anhydrides thereof. Incidentally, ester residue R ₁₀ does not need to be a one polyhydric alcohol and one polybasic acid, it may be composed of two or more polybasic acids, respectively.

Specific examples of such a polyester acrylate include:

Embedded image

Embedded image

Embedded image And the like.

The preferred amounts of the components (A) and (B) (total of 100 parts by weight) are as follows:
For 95 parts by weight, more preferably 40 to 90 parts by weight, 70 to 5 parts by weight, more preferably 60 parts by weight of the component (B).
To 10 parts by weight. If the amount of the component (A) is less than 30 parts by weight, characteristics such as hardness, water resistance, and gloss based on the component (A) are insufficient. Poor solvent resistance. When the component (B) exceeds 70 parts by weight, the water resistance, hardness,
The adverse effects of poor abrasion resistance and large curing shrinkage appear. On the other hand, when the component (B) is less than 5 parts by weight, the curing rate is low, and the cured film is brittle and easily cracks, which is not preferable.

In addition to the components (A) and (B), a compound having a polymerizable monofunctional unsaturated group is used in combination to adjust the viscosity by dilution, adhesion to a substrate, antistatic properties, and other properties. It is also possible to improve. A wide selection of monomers of this type is possible, but methyl methacrylate, 2-ethylhexyl methacrylate, cyclohexyl acrylate, isobornyl methacrylate, glycidyl methacrylate, 2-methacryloyloxyethyl-acid phosphate, methacrylic acid, N-vinyl-
Examples thereof include 2-pyrrolidone and styrene.

As the polymerization initiator which is the component (C), various conventionally known polymerization initiators can be used. That is, when cured by heating, benzoyl peroxide, peroxides such as lauroyl peroxide, hydroperoxides such as butyl hydroperoxide, azo compounds such as azobisisobutyronitrile alone or It is used as a polymerization initiator in combination with a curing accelerator such as an amine or a metal soap. When curing with high energy radiation, acetophenone, propiophenone, benzophenone, benzoin,
Examples thereof include benzoin alkyl ether, xanthol, fluorenone, benzaldehyde, fluorene, anthraquinone, 3-methylacetophenone, 4-chlorobenzophenone, and 4,4'dimethoxybenzophenone. However, when curing is performed using an electron beam, the above-mentioned initiator may not be added.

These polymerization initiators can be used alone or in combination of two or more. or,
In the present invention, when the above polymerization initiator is used,
It is also possible to further enhance the ultraviolet curability by using a so-called accelerator such as a graded amine. As the tertiary amine, various aliphatic and aromatic tertiary amines can be used, and examples thereof include N-dimethanolamine, triethanolamine, N-methyldiethanolamine, triethylamine, and ethyl P-dimethylaminobenzoate. .

When these polymerization initiators and accelerating assistants are used except for the case of electron beam irradiation, 0.1 to 10 parts by weight based on 100 parts by weight of the total amount of both components (A) and (B) And more preferably in the range of 1 to 4 parts by weight.
If the amount of the component (C) is less than 0.1 part by weight, the curing speed is slow and impractical. If the amount exceeds 10 parts by weight, the strength and weather resistance are adversely affected.

The composition composed of the components (A), (B) and (C) is generally used after preliminarily mixing and preserving it. Even in some places, polymerization, gelation, etc. may occur, so keep the three components separately and mix them before use, or store them in a mixture of both (A) and (B). Before use, a method such as adding the component (C) and mixing the components is used. There is no particular problem when only the components (A) and (B) are used. When mixing the three components, a solvent such as butanol, methyl cellosolve, or butyl cellosolve may be added as necessary.

The composition can be cured by blending various substances or compounds for the purpose of improving the physical properties of the cured product or depending on the use of the cured product. These additives include hydroquinone and P as heat stabilizers.
-Methoxy phenol, phthalocyanine blue, phthalocyanine green, titanium white, etc. as coloring pigments; silica, calcium carbonate, kaolin, clay, colloidal silica, etc. as a thickener; various ultraviolet absorbers, antioxidants, etc. A normal diorganopolysiloxane or the like may be added according to the purpose of use as long as the characteristics of the composition are not impaired.

The composition prepared as described above is applied to the surface of the hardened cementitious material. The hardened cementitious material is as follows. First, as cementitious materials used as a binder, Portland cement, blast furnace cement, fly ash cement, alumina cement, magnesia cement, gypsum, etc. are mentioned, and if necessary, a siliceous material is added to these cementitious materials. May be.

In addition, various aggregates, fillers, and extenders, for example, sand, natural and artificial lightweight aggregates, fly ash, slag, cinder, perlite, etc. may be added. It may be used and reinforced. The shape of the cementitious hardened body has a plate shape, a cylindrical shape, an irregular shape, and the like.
Various molding methods such as press, roll, extrusion, and papermaking can be adopted.

The cured cementitious body may be colored by adding a pigment to a cementitious material or by applying a coloring paint containing a pigment on the surface. Examples of the inorganic pigment used for coloring the cementitious cured product include titanium oxide, carbon black, iron oxide, cadmium compound, cobalt compound, graphite, zinc chromate, cyanamide lead, white Portland cement and the like.

In the case where the above pigment is added to the cementitious cured product, only a pale and dull color was conventionally obtained, but the component (A), (B), (C) or (A) By applying and curing the composition comprising the components (B) and (B), it is possible to realize deep and vivid original color development.

Here, as a pre-coating step of the composition, the surface of the cementitious cured product containing an inorganic pigment may be polished. This is to remove substances that impair coloring. Polishing can be performed by a generally known method such as a belt sander and a sand blast. The cementitious cured product may have a colored layer only on the surface. That is, a cured product having a predetermined shape may be added with an inorganic pigment as necessary together with a cementitious material and kneaded with water, and then applied and cured. As a method for applying the hardened cementitious material or the composition, any method such as spray coating, brush coating, dip coating, flow coating, and spin coating is used.

The thickness of the composition when it is applied to a hardened cementitious material is preferably from 3 to 100 μm.
In the case of a thick film having a thickness of m or more, the content of uncured monomer increases during curing, and moreover, adverse effects such as cracks tend to occur in the cured film. When curing the composition, in the case of thermal curing, the composition is heated to 40 to 90 ° C. using steam, electric heat, infrared rays or the like in a furnace, and in the case of ultraviolet curing, an ultraviolet fluorescent lamp, a high pressure The irradiation is performed using a mercury lamp, a carbon arc lamp, a metal halide lamp, or the like, and the irradiation amount can be appropriately selected. In the case of electron beam irradiation, it is performed using various accelerators.

[0034]

The hardened cementitious coating agent of the present invention comprises:
A composition comprising a (meth) acryl-functional polyorganosilsesquioxane, a poly (meth) acrylate and a polymerization initiator, which is applied to a cementitious cured product surface,
Cured coatings can be produced by various curing methods. In other words, by applying the composition to the surface of the cementitious cured body and irradiating it with high-energy radiation to cure the composition, heat curing is not required and the reaction can be performed at room temperature. Problems such as blistering and cracking of the coating film caused by heat curing were solved.
In addition, it has been found that the above-mentioned problem can be avoided by performing the heating and curing at 40 to 90 ° C. because the evaporation of water does not occur. In addition, when an inorganic pigment was added to the cementitious cured product, it became possible to form a dark and vivid color because the substance that hinders the coloring of the surface layer was removed by prior polishing of the surface of the cementitious cured product, This is considered to be because the material penetrates deeply into the porous portion of the surface of the cementitious cured product, and after curing, forms a transparent and flat cured film.

The cured film thus obtained not only retains the gloss, water resistance, hardness, abrasion resistance and the like characteristic of the ladder type polysiloxane represented by the formula (I),
Poly (meth) acrylate has characteristics such as easy curability and easy compatibility with various functions.

[0036]

The present invention will be described below in detail with reference to examples. “Parts” in the examples indicate “parts by weight” unless otherwise specified. In addition, each physical property value in an Example was measured according to the following method.

(Abrasion resistance) A bundle of steel wool having a thickness of # 0000 was rubbed 15 times with the cured coating while applying a load of 500 g, and then the degree of scratches on the coating was examined and evaluated in four ranks as follows. did. A: No scratches B: No more than 10 scratches C: 10 or more scratches but still retains gloss D: Loss of gloss with countless scratches (Surface hardness) Pencil for paint JIS using a scratch tester
It was measured according to K5401. (Water resistance) The film was immersed in warm water at 800 ° C., and the time during which abnormalities such as cracks occurred in the cured film was measured. (Weather resistance) A carbon arc sunshine weather meter test was performed in accordance with the provisions of JIS B7753. The judgment was made by comparing and observing the surface of the test specimen after 500 hours with that of the test specimen.

(Synthesis Example 1 of Component (A)) A 1-liter flask equipped with a thermometer, a stirrer, and a reflux condenser was placed in a flask.
γ-methacryloxypropyltrimethoxysilane 149
g (0.6 mol), 356 g of methyltriethoxysilane
(2.0 mol), 96 g of phenyltriethoxysilane
(0.4 mol), 0.002 mol of hydrochloric acid, 108 g of water (6
Mol), 0.01 g of P-methoxyphenol,
The temperature in the flask is raised to 60 ° C., and
Hold for 0 minutes. Subsequently, the temperature was raised to 70 ° C., and the mixture was reacted for 1 hour. Then, 0.6 g (0.0082 mol) of n-butylamine was added dropwise, and the mixture was further reacted for 45 minutes.
4 g (0.0087 mol) was added dropwise and kept at 70 ° C. for 30 minutes. After washing with water, dehydrated with anhydrous sodium sulfate,
When the solvent was removed using a rotary evaporator, 2
Viscous (A) -1 component 320 having a viscosity of 450 cps at 5 ° C.
g was obtained. The molecular weight of this component (A) -1 was determined by GPC and found to be a number average molecular weight of 5,700 and a weight average molecular weight of 13,800. In the component (A) -1 of this synthesis example, the molar ratio of the methyl group, phenyl group, and methacryl group in the side chain was about 67:13:20.

(Synthesis Example 2 of Component (A)) A 1-liter flask equipped with a thermometer, a stirrer, and a reflux condenser was placed in a 1-liter flask.
γ-methacryloxypropyltrichlorosilane 128 g
(0.5 mol), 450 g of methyltrichlorosilane
(3.0 mol), 42 g of phenyltrichlorosilane
(0.2 mol), 80 g (5 mol) of water, and 0.01 g of P-methoxyphenol.
C. and kept for 60 minutes with stirring. Then gradually raise the temperature, keep at 90 ℃ for 15 minutes,
It was returned to room temperature and neutralized with sodium hydroxide. The reaction solution was filtered, washed with water, dehydrated with anhydrous sodium sulfate, and desolvated using a rotary evaporator. The viscosity was 600 cps at 25 ° C (A) -2.
The components were obtained. The number average molecular weight of the component (A) -2 determined by GPC was 4,800, and the weight average molecular weight was 11,000.
Met. The molar ratio of the side chain methyl group, phenyl group and methacryl group was about 88: 4: 8.

Example 1 20 parts of (A) -1 component, 27 parts of pentaerythritol tetraacrylate, 4 parts of N-vinyl-2-pyrrolidone, 6 parts of caprolactone-modified dipentaerythritol hexaacrylate, 1.5 parts of benzophenone, Ethyl p-dimethylaminobenzoate 1.5
Parts, 35 parts of methyl cellosolve and 5 parts of butyl cellosolve were mixed to prepare a curable composition. As a cementitious cured product, white Portland cement was used as a binder on a 10 mm thick slate plate, and a colored paint containing silica and mica as fillers and methylcellulose as a thickener was added to a thickness of 1 mm. A plate material spray-coated was used. 50 g of the composition is added to the plate-like material.
/ M ² was spray coated. Next, using a high-pressure mercury lamp, irradiation was performed uniformly so that the irradiation amount of ultraviolet rays became ² J / cm ² , and the composition was cured. As a result, the plate before being coated with the composition had a whitish and unclear appearance peculiar to the cement-based colored plate, but after coating, changed completely to a dark, colorful and glaze-like glossy appearance. No adverse effects such as warpage and cracks due to curing were observed. Table 1 shows the physical properties of the cured film.

Example 2 42 parts of the component (A) -2, 28 parts of trimethylolpropane triacrylate, 10 parts of isobornyl acrylate, 1 part of benzoyl peroxide and 12 parts of methyl isobutyl ketone were mixed together to form a curable composition. I got something. This composition was spray-coated in the same manner as in Example 1 on a plate-like material obtained by applying a color pigment to the same slate plate as in Example 1, and was cured in an oven at 80 ° C. This cured film also had a good appearance as in Example 1. The various physical properties are shown in Table 1.

(Example 3) White Portland cement was used as a binder in a slate plate having a thickness of 10 mm, and titanium oxide and iron oxide as pigments, silica and mica as fillers, and methylcellulose as a thickener were added thereto. A base material was prepared by spray-coating a colored coating material to a thickness of 1 mm and hardening the surface of a plate-like material. The curable composition of Example 1 was spray-coated on the base material in the same manner as in Example 1, and ultraviolet light was applied. Curing was performed. As a result, the board before being coated with the composition has a whitish and unclear appearance peculiar to the cement-based colored board, but when the cured film of this example is combined, a dark colored vivid and tile-like glossy appearance is obtained. Has changed completely. Also, no adverse effects such as warping and cracks due to curing were observed at all. Table 1 shows the physical properties of the cured film.

Example 4 White Portland cement was used as a binder, and iron oxide, silica, mica,
A mixture of fiber reinforcing material, methylcellulose and water was extruded into a plate having hollow ribs using a vacuum kneader, and a saturated steam pressure of 10 kg / cm using an autoclave.
^After curing for 6 hours at ² and polishing the surface with a belt sander, a cured cementitious substrate was used. The UV-curable composition of Example 1 was spray-coated in the same manner as in Example 1 and cured by UV. Again, a clear and glossy cured film was obtained. Table 1 shows the physical properties of this cured film.
Are shown together.

(Example 5) Using α-gypsum as a binder, and blending it with a cobalt compound, silica, mica, a fiber reinforcing material and water, the mixture was formed into a large-sized tile having irregularities. Was spray-coated with the curable composition of Example 2, and cured in a heating furnace in the same manner as in Example 2. As a result, colorful tiles with a glaze tone were obtained. Table 1 shows the physical properties of the cured film.

[0045]

[Table 1]

[0046]

According to the method for coating a cured cementitious body of the present invention, the glaze-like gloss, hardness, abrasion resistance, water resistance, and weather resistance are excellent without being hindered by the moisture and crystallization water of the cured cementitious body. The cured coating can be applied to the surface of the cementitious cured product, and can be widely used in fields including construction and decoration.

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takuhiko Motoyama 1-13-9 Shiba Daimon, Minato-ku, Tokyo Showa Denko KK (56) References JP-A-4-182371 (JP, A) JP-A Sho 62-197423 (JP, A) JP-A-4-76059 (JP, A) JP-A-3-281616 (JP, A) JP-A-4-50243 (JP, A) JP-A-4-28722 (JP, A A) JP-A-4-33936 (JP, A) JP-A-4-31806 (JP, A) JP-A-4-271306 (JP, A) JP-A-4-178411 (JP, A) JP-A-62 JP-A-275132 (JP, A) JP-A-56-151731 (JP, A) JP-A-3-296515 (JP, A) JP-A-63-117024 (JP, A) JP-A-4-353521 (JP, A) (58) Fields investigated (Int.Cl. ⁶ , DB name) C04B 41/00-41/91 C09D 1/00-201/10 C08F 290/00-290/14 C08F 299 / 00-299/08

Claims (3)

(57) [Claims] 1. A composition comprising the following components (A), (B) and (C) is applied to the surface of a cementitious cured product,
A method for coating a hardened cementitious body, wherein the coating is cured by heating to 0 to 90 ° C. or by irradiating with high-energy radiation. (A) a (meth) acryl-functional polyorganosilsesquioxane represented by the following general formula (I): (Wherein R ₁ and R ₂ represent an alkyl group having 1 to 3 carbon atoms, a phenyl group, an acryl represented by the following general formula (II) and / or
Or, it contains a methacryl functional group, and each of the m structural units is the same or different. R ₃ , R ₄ , R ₅ , and R ₆ are each composed of two or more selected from the group consisting of a hydrogen atom, a methyl group, and an ethyl group, and the hydrogen atom is always included. m indicates the degree of polymerization. The general formula (II) is Wherein R ₇ represents a hydrogen atom or a methyl group, R ₈ is a substituted or unsubstituted divalent hydrocarbon having 1 to 12 carbon atoms, R _7,
R ₈ may be different among m structural units. ) (B) a poly (meth) acrylate represented by the following general formula (III): (Wherein R ₉ is a hydrogen atom or a methyl group, and one R
₉ may all not be the same. R ₁₀ is a polyvalent hydrocarbon residue having a (meth) acrylic acid residue bonded to a different carbon atom, a polyvalent hydrocarbon residue having oxygen in the main chain, or a polyhydric alcohol and a polybasic acid Represents a residue of an ester, and 1 is an integer of 2 or more. (C) Polymerization initiator 2. A cementitious material characterized by applying a composition comprising the components (A) and (B) according to claim 1 to the surface of a hardened cementitious material and irradiating it with an electron beam. Coating method of cured body. 3. The method for coating a hardened cementitious body according to claim 1, wherein the surface of the hardened cementitious body containing an inorganic pigment is polished and then coated on the surface.