JP2001347221A - Coating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for coating concrete without surface finish in which both the rough surface touch and the high durability of the concrete can be achieved and also a method for coating a ceramic tile mortar joint face in which the waterproofness of the joint face can be improved. SOLUTION: A water repellent (A), containing an organic zirconium compound and its polycondensation product as useful components, which is represented by the formula (1): (RO)a.Zr(OCOR')4-a (provided, however, that a is 2 or 3, R is a 1-4C alkyl group and R' is an 8 or more C alkyl group), is applied to the surface of the concrete formed without surface finish or the ceramic tile mortar joint face.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating method capable of imparting a finished appearance and a high durability that do not impair the texture of exposed concrete, and at the same time, increasing the waterproofness of a mortar portion of a porcelain tile joint. .

[0002]

2. Description of the Related Art In recent years,
Exposed concrete is widely used in structures such as public facilities, schools, hospitals, and houses because of the natural finished appearance of the concrete surface. However, when water such as rainwater reaches the concrete surface, the concrete surface becomes darker than its original color, and a phenomenon (wet color) occurs in which the original material and texture of the concrete are lost. Also, when a clear paint is applied for the purpose of protecting the base material from rainwater or the like, the color may become wet, and in order to avoid the “wet color” phenomenon in concrete coating, an alkylalkoxysilane condensate or the like is used. 2. Description of the Related Art There has been widely known a method of coating a water-repellent agent to prevent a wet color phenomenon of concrete due to rainwater and maintain the texture and durability of concrete. Further, when a clear paint is further applied as a protective film on the concrete to which the water repellent agent has been applied, rainwater permeates the clear paint film and does not become wet even when it reaches the concrete surface. Further, in recent years, a coating specification capable of preventing a wet color phenomenon of concrete by clear coating by devising a combination of the water repellent agent and the clear coating has been widely used.

[0003] However, in the above method, the siloxane bond is hydrolyzed by alkali derived from the concrete, so that the durability of the water repellency is not sufficient. There was a problem that additional coating in a short cycle was required to prevent the wet color.

On the other hand, when the mortar portion of the porcelain tile joint used for the outer wall of a porcelain tile finish building and the like becomes less waterproof over time, water enters the back surface of the porcelain tile, and the porcelain tile layer deteriorates and falls. This can cause serious accidents, and in many cases, renovation works of porcelain tile-finished buildings require enormous costs. As an example of the countermeasure, a silicon-based water-repellent treatment agent may be applied to the mortar joint surface of the porcelain tile. However, from the above-mentioned problem, improvement of the water-repellency sustainability has been desired.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in order to solve the above-mentioned problems. As a result, a water-repellent agent containing a specific organic zirconium compound as an active ingredient is applied to concrete and porcelain tile mortar surfaces. By painting,
The present inventors have found that the coated surface exhibits water repellency, and that its durability is remarkably improved. That is, the present invention provides: The following formula (1) (RO) _a · Zr (OCOR ′) _4-a (1) (where a is 2 or 3 and R is 1 to 4 carbon atoms) on the exposed concrete surface or the porcelain tile mortar joint surface Wherein R ′ is an alkyl group having 8 or more carbon atoms.) And a water-repellent agent (A) containing a polycondensate thereof as an active ingredient. 1. A coating method characterized by: 2. The coating method according to item 1, wherein after applying the water repellent agent (A), the clear coating material (B) is further applied. The following formula (1) (RO) _a · Zr (OCOR ′) _4-a (1) (where a is 2 or 3, R is an alkyl group having 1 to 4 carbon atoms, and R ′ is 8 carbon atoms. 3. An organic zirconium compound represented by the formula (1) or a water-repellent treatment agent used in the coating method according to item 1 or 2, which comprises a polycondensate thereof as an active ingredient. I do.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The exposed concrete to which the present invention is applied is a conventionally used exposed concrete, which has a water content of 10% by weight or less before applying a water-repellent agent, Preferably 8% by weight
Desirably, it is dried in the following range. By setting the water content of the concrete to 10% by weight or less, there is an advantage that the water repellent agent (A) is easily impregnated into the concrete inner surface. The mortar joint surface of the porcelain tile is preferably made of a cementitious material and sand and has a water content similar to that of the bare concrete.

[0007] The present invention water repellent agent used in (A) is the following formula _{(1) (RO) a ·} Zr (OCOR ') 4-a (1) ( wherein a is 2 or 3, R is carbon An alkyl group having 1 to 4 carbon atoms, and R 'represents an alkyl group having 8 or more carbon atoms), and a polycondensate thereof as an active ingredient. The alkoxy group in such an organic zirconium compound undergoes hydrolysis and polycondensation due to the presence of water in the base material in the process of infiltrating the base material, and the hydrolyzate and / or polycondensate is converted into concrete or mortar. Chemically bond with the Si-OH group (silanol group) of the compound to form a hydrophobic film. The Zr—O—Zr bond formed here has stronger alkali resistance than the siloxane bond, and has better hydrolysis resistance than the siloxane bond.

In the formula (1), a is preferably 2 or 3. When a is 1, the chemical bond with concrete and mortar is insufficient, while when a is 4, it is difficult to obtain a water-repellent effect, which is not preferable.

In the formula (1), R is an alkyl group having 1 to 4 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group and a t-butyl group. An alkyl group having more than 5 carbon atoms is not preferred because hydrolysis by moisture in the base material becomes difficult and the effect of improving the adhesion to the base material decreases.

In the formula (1), R 'represents an alkyl group having 8 or more carbon atoms, and more preferably an alkyl group having 12 to 18 carbon atoms.
Specific examples include dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, and octadecyl groups. When R 'is less than 8, the formation of the hydrophobic layer becomes insufficient and sufficient water repellency tends to be not obtained, which is not preferable. On the other hand, if it exceeds 18, it becomes a solid, which may reduce the handling labor, the solubility in the solvent, and the permeability to the base material.

As the organic zirconium compound, for example, “Orgatic ZB-320” (active ingredient (C ₄ H ₉
O) ₃ Zr (OCOC ₁₇ H ₃₅ )), “Orgatics ZB
−410 ”(active ingredient (C ₄ H ₉ O) ₃ Zr (OCOC ₁₂ H
₂₅ ), above, manufactured by Matsumoto Pharmaceutical Co., Ltd.), and condensates thereof. These can be used alone or in combination of two or more.

The water-repellent treating agent (A) used in the present invention may further comprise a conventionally known alkylalkoxysilane compound,
And polycondensates thereof may be used as a mixture.
The mixing ratio of the alkylalkoxysilane compound and its polycondensate to the total weight of the water-repellent treating agent (A) is 5%.
Up to 0% by weight is preferred. If it exceeds 50% by weight, water repellency,
It is not preferable because the durability of waterproofing becomes insufficient. Examples of the alkylalkoxysilane include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane,
Triacetoxysilane, trimethoxymethylsilane, trimethoxyethylsilane, trimethoxypropylsilane, trimethoxyphenylsilane, vinyltrimethoxysilane, vinyltris (methoxyethoxy) silane, γ
-Methacryloyloxypropyltrimethoxysilane,
γ-glycidoxypropyltrimethoxysilane, methoxymethyldiethylsilane, dimethoxydimethylsilane,
Examples include dimethoxydiethylsilane, dimethoxydiphenylsilane, and one or more condensates thereof. These can be used alone or in combination of two or more.

In the present invention, the concentration of the water-repellent treating agent (A) is usually 10 to 70% by an organic solvent, and more preferably 30 to 5%.
It is preferable that the coating be performed after adjusting to a range of 0%. Examples of the organic solvent include aromatic hydrocarbons such as toluene and xylene, ketones such as methyl isobutyl ketone and cyclohexanone, n-butanol, ethyl cellosolve, butyl cellosolve, methoxypropanol, and diethylene glycol monobutyl ether. Alcohols, n-hexane, n-octane, 2,2,
2-trimethylpentane, isooctane, n-nonane,
Aliphatic hydrocarbons such as cyclohexane and methylcyclohexane, "Solvent A" (manufactured by Nippon Oil Co., Ltd.), "Swazol 100" (manufactured by Maruzen Petrochemical), mineral spirits, petroleum ether, petroleum benzene, petroleum naphtha, etc. Petroleum solvents and the like. These can be used alone or in combination of two or more.

An organic tin compound such as dibutyltin dilaurate may be added in order to promote a reaction in which the alkoxy group and water in the air cause hydrolysis and condensation reactions. The amount of addition is 0.0 with respect to the total weight of the water repellent agent (A).
About 5% by weight is suitable.

In the method of the present invention, the water-repellent agent (A) obtained as described above is exposed and painted on concrete or on a porcelain tile mortar joint.
05 to 0.2 kg / m ² / time, preferably 0.1 to 0.2 kg / m ² / time.
A range of 15 kg / m ² / time is preferred. The coating method is not particularly limited, but it can be performed by means such as spray coating, roller coating, brush coating, and flow coating.

It is also possible to coat the above water-repellent agent (A) on the surface to which the water-repellent agent (A) has been applied, further by applying the above-mentioned alkylalkoxysilane and a water-repellent agent based on a condensate thereof.

In the next step, the above-mentioned alkylalkoxysilane-based water-repellent agent or clear paint (B) described later is used.
Is applied over the water-repellent agent (A), the drying of the film coated with the water-repellent agent (A) is, for example, at a drying temperature of 20 ° C. in a range of about 2 hours to 7 days. Is preferred.

In the present invention, the surface of the exposed concrete is protected by the coating with the water-repellent treating agent (A) while maintaining its original texture, and the waterproofness of the porcelain tile mortar joint is improved. It is also possible to apply a clear coating (B) to the coated surface for forming. As the clear coating (B), a conventionally known water-based and / or solvent-based clear coating can be used. Examples of the aqueous clear paint include an emulsion paint in which a crosslinked or non-crosslinked aqueous resin is dispersed in water. Examples of the emulsion paint include (meth) acrylic acid alkyl ester copolymer emulsion paint and styrene- (meth) acrylate. ) Acrylic acid alkyl ester copolymer emulsion paint, polyester resin emulsion paint, silicone resin emulsion paint, fluororesin emulsion paint, urethane resin emulsion paint, and the like. As the solvent-based clear coating, for example, the resin component used in the aqueous clear coating exemplified above is an organic solvent (e.g., aromatic, ester, ketone, alcohol, ether, aliphatic hydrocarbon-based, etc. One or a combination of two or more thereof may be used. Depending on the composition of the clear paint, the concrete may become a wet color, but it is more preferable to use an aqueous clear paint in the method of the present invention.

The clear coating material (B) used has a resin solid content of usually from 20 to 60% by weight, particularly from 30 to 50% by weight, and the coating amount is about 0.05 to 0.12.
Kg / m ² , preferably 0.08 to 0.1 kg / m ² . A range of 10 kg / m ² is preferred. The coating method is not particularly limited, but it can be performed by means such as spray coating, roller coating, brush coating, and flow coating. If the coating amount is less than this range, the protective ability of the coating film is reduced. If the coating amount is more than this range, it is not preferable because, when the concrete is applied, the color becomes wet and the appearance becomes poor.

[0020]

The present invention will be described in more detail with reference to the following examples.
explain. In addition, "part" and "%" in the text are
Parts by weight "and"% by weight ".Production of water repellent agent (A) Preparation Example 1 "Orgatics ZB-320" (Matsumoto Pharmaceutical Co., Ltd.
Product name, active ingredient (C_FourH ₉O)_ThreeZr (OCOC₁₇H₃₅))
30 parts, “Solvent A” (product name, stone
Oil-based hydrocarbon solvent) and disperse enough.
The water-repellent agent A1 was obtained by uniformly stirring the mixture.

Preparation Examples 2 to 6 Preparation Examples A2 to A6 were obtained in the same manner as in Preparation Example 1 except that the formulations shown in Table 1 were used.

[0022]

[Table 1] Table 1

Note 1) "Orgatics ZB-320": pine
Product name, active ingredient (C_FourH₉O)_ThreeZr
(OCOC₁₇H₃₅Note 2) "Orgatics ZB-410": Matsumoto Pharmaceutical Company Limited
Made, active ingredient (C_FourH₉O)_ThreeZr (OCOC₁₂H_{twenty five}Note 3) "Orgatics ZB-430": Matsumoto Pharmaceutical Company Limited
Made, active ingredient (C_FourH₉O)_FourZr Note 4) "Orgatics ZB-530": Matsumoto Pharmaceutical Company Limited
Made, active ingredient (C_FourH₉O)_ThreeZr (OCOC₇H_FifteenNote 5) "XC98-A9426": manufactured by Toshiba Silicon Corp.
Product name, active ingredient (CH _ThreeO)_ThreeSiC₆H₁₃ Note 6) "Solvent A": Nippon Oil Corporation, trade name, petroleum-based
Hydrocarbon solventsManufacture of test specimen Examples 1 to 4 and Comparative Examples 1 to 4 The test substrate had a length x width x thickness of 75 mm x 75 mm
A mortar plate of 10 mm was used. On the surface of the test board
Each water repellent agent obtained in the above preparation example was applied with a brush, and the applied amount was 8
5-100g / m^Two/ Twice and paint at room temperature
For 7 days. Example 4 and Comparative Example 4 In Example 4, the water-repellent treatment agent A1 was used, and in Comparative Example 4, the water-repellent treatment agent A1 was used.
Each test specimen coated with Agent A4 was dried at room temperature for one day.
In addition, as a clear hanging process,
Mu ”(water-based clear paint: Kansai Paint Co., Ltd.)
(Solid content 45%) with a brush 100 g / m^Two/
Paint once, dry at room temperature for 7 days
It was a specimen.

Each of the obtained test specimens was tested according to the following test method. The test results are shown in Table 2 below.

[0025]

[Table 2] Table 2

Water repellency and water repellency sustainability The water repellency was evaluated by dropping a water drop on the surface of each test piece and measuring the angle (water contact angle) between the test piece surface and the water drop using an angle measuring device. The water repellency is JIS B
Evaluation was made by measuring the water contact angle after exposure to a tester (sunshine weather meter) specified in 7753 for 250 hours and 500 hours. Here, the water contact angle after 500 hours of the accelerated test was judged to be acceptable if it was 60 ° or more.

After completion of the accelerated test for 500 hours, the test piece was instantly submerged in water, and the surface of the test piece after lifting was visually evaluated for water wetting. A: No abnormality. ：: The submerged part is colored a little darker than the unsubmerged part, but the recovery is quick. Δ: The submerged part is colored a little darker than the unsubmerged part, and the recovery is slow. ×: The submerged portion is markedly colored darker than the non-submerged portion, and hardly recovers.

[0028]

By carrying out the method described above,
A water-repellent protective film can be easily formed without impairing the feel of concrete, and the protective film has good adhesion to a clear coating film and excellent weather resistance. Also,
According to the method of the present invention, the waterproofness of the porcelain tile mortar joint is also excellent.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4D075 AE03 CA36 DB12 DB14 EA13 EA43 EB16 EB22 EB31 EB35 EB38 EB42 EB56 4H020 BA04 BA05 4J038 DM001 NA01 NA04 NA07 PB05 PC04

Claims (3)

[Claims] 1. The following formula (1) (RO) _a · Zr (OCOR ′) _4-a (1) (where a is 2 or 3 and R is carbon) on the exposed concrete surface or the porcelain tile mortar joint surface. An alkyl group having 1 to 4 groups, and R 'represents an alkyl group having 8 or more carbon atoms.) And a water-repellent agent containing a polycondensate thereof as an active ingredient A coating method characterized by coating (A). 2. The coating method according to claim 1, further comprising applying a clear paint (B) after applying the water repellent agent (A). 3. The following formula (1) (RO) _a · Zr (OCOR ′) _4-a (1) (where a is 2 or 3, R is an alkyl group having 1 to 4 carbon atoms, R ′ Represents an alkyl group having 8 or more carbon atoms), and a polycondensate thereof as an active ingredient.
A water-repellent treatment agent used in the coating method described above.