JP6947063B2 - Aqueous paint composition - Google Patents

Description

The present invention relates to a water-based coating composition.

As a method of applying a water-based paint containing colored aggregate to the inner and outer walls of a building or a structure, spray application using a dedicated spray gun is used. Spray coating has the advantage of quick construction, but has the disadvantages of wasteful paint due to the large amount of paint scattered and the need for technical skills for painting.

Further, as a method of applying the water-based paint, roller coating using a roller such as a middle hair roller can be mentioned. Roller application has merits such as thick application and easy application, and less waste of paint. For example, when a medium-hair roller is used, aggregates are entangled in the hair, the workability at the time of application is poor, and a uniform coating film is formed. There was a problem such as not being done.

Japanese Unexamined Patent Publication No. 2005-179573

The present invention has been made in view of such circumstances, and provides a water-based coating composition containing a colored aggregate, which has good workability at the time of roller application using a roller such as a middle hair roller. The purpose is.

As a result of diligent studies to achieve the above object, the present inventors have made a water-based coating composition containing a synthetic resin emulsion, mica having a predetermined average particle size, and calcium carbonate, particularly using a medium-hair roller or the like. The present invention has been completed by finding that it is excellent in workability when the roller is applied.

（式中、Ｒ¹は、水素原子又はアルキル基であり、Ｒ²〜Ｒ⁴は、それぞれ独立に、水素原子、−ＯＲ¹、アルキル基又はアリール基である。）
３．更に、（ｄ）増粘剤を含む１又は２の水性塗料組成物。
４．中毛ローラー塗布用である１〜３のいずれかの水性塗料組成物。 That is, the present invention provides the following water-based coating composition.
1. 1. (A) Synthetic resin emulsion,
It contains (b) mica with an average particle size of 0.3 to 3 mm and (c) calcium carbonate with an average particle size of 0.1 to 0.5 mm.
The content of the component (b) is 3 to 30 parts by mass, and the content of the component (c) is 20 to 100 parts by mass with respect to 100 parts by mass of the solid content in the component (a).
The viscosity measured with a B-type viscometer under the conditions of a rotation speed of 20 rpm and a paint temperature of 25 ° C. is 1,000 to 100,000 mPa · s.
A water-based paint composition having a Ti value (viscosity at a paint temperature of 25 ° C. and a rotation speed of 2 rpm / viscosity at a paint temperature of 25 ° C. and a rotation speed of 20 rpm) of 2 to 8.
2. The aqueous coating composition of 1 in which the synthetic resin emulsion is an emulsion containing an alkoxy group or hydroxyl group-containing organic silane compound represented by the following formula (1) or a condensate thereof, and / or a fluororesin.

(In the formula, R ¹ is a hydrogen atom or an alkyl group, and R ^{2 to} R ⁴ are independently a hydrogen atom, −OR ¹ , an alkyl group or an aryl group.)
3. 3. Further, (d) a water-based coating composition of 1 or 2 containing a thickener.
4. The aqueous coating composition according to any one of 1 to 3 for applying a medium-hair roller.

The water-based coating composition of the present invention contains a synthetic resin emulsion and mica having a predetermined average particle size and calcium carbonate at a predetermined concentration, and thus has excellent workability at the time of roller coating using a medium-hair roller or the like. , A uniform coating film can be formed.

The aqueous coating composition of the present invention comprises (a) a synthetic resin emulsion, (b) mica having an average particle size of 0.3 to 3 mm, and (c) calcium carbonate having an average particle size of 0.1 to 0.5 mm. Is included.

[(A) component]
The synthetic resin emulsion of the component (a) is not particularly limited, and examples thereof include an emulsion containing an organic silane compound or a condensate thereof, a fluororesin emulsion, an acrylic resin emulsion, an acrylic silicon resin emulsion, an acrylic urethane resin emulsion, and a urethane resin emulsion. Be done. Of these, silicone-based emulsions and fluororesin emulsions are preferable.

As the emulsion containing the organic silane compound or its condensate, an emulsion containing an alkoxy group- or hydroxyl group-containing organic silane compound represented by the following formula (1) or a condensate thereof is preferable.

In formula (1), R ¹ is a hydrogen atom or an alkyl group. R ^{2 to} R ⁴ are independently hydrogen atoms, −OR ¹ , alkyl groups or aryl groups, respectively.

The number of carbon atoms of the alkyl group is not particularly limited, but in the present invention, 1 to 10 is preferable, and 1 to 5 is more preferable. Further, the structure may be linear, branched or annular. Specific examples of the alkyl group include methyl group, ethyl group, n-propyl group, i-propyl group, cyclopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group and cyclobutyl group. Examples thereof include n-pentyl group, cyclopentyl group, n-hexyl group, cyclohexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group and the like.

The number of carbon atoms of the aryl group is not particularly limited, but in the present invention, 6 to 20 is preferable, and 6 to 14 is more preferable. Specific examples of the aryl group include a phenyl group, an α-naphthyl group, a β-naphthyl group, an o-biphenylyl group, an m-biphenylyl group, a p-biphenylyl group, a 1-anthryl group, a 2-anthryl group and a 9-anthryl group. Examples thereof include a group, a 1-phenanthryl group, a 2-phenanthryl group, a 3-phenanthryl group, a 4-phenanthryl group, a 9-phenanthril group and the like.

In particular, as the organic silane compound represented by the formula (1), ^{it is more preferable to use a compound in which R 1} is a methyl group and R ^{2 to} R ⁴ are independently methyl groups, phenyl groups or methoxy groups.

Examples of the organic silane compound include tetraalkoxysilanes such as tetramethoxysilane and tetraethoxysilane; alkyltrialkoxysilanes such as methyltrimethoxysilane, methyltriethoxysilane and methyltriisopropoxysilane; phenyltrimethoxysilane and phenyltriethoxy. Examples thereof include aryltrialkoxysilanes such as silanes.

Examples of the condensate of the organic silane compound include those obtained by adding water to a single compound of the organic silane compound or a mixture of two or more kinds and (partially) hydrolyzing and condensing the compound. The degree of condensation of the condensate is generally in the range of 2 to 100, and from the viewpoint of compatibility, a liquid having a degree of condensation of 2 to 15 is preferable.

As the organic silane compound or a condensate thereof, one having a lower limit of Si content of 15% by mass is usually used from the viewpoint of weather resistance and stain resistance of the coating film, but it is preferably 20% by mass. On the other hand, the upper limit of the Si content is not particularly limited, but is generally about 50% by mass, preferably 40% by mass, and more preferably 35% by mass. The Si content can be measured, for example, by the method described in Japanese Patent No. 4906219.

Further, as the organic silane compound or a condensate thereof, a commercially available product can be used, and specific examples thereof include DC3074 (Si content 25% by mass) and SR2402 (Si content 30) manufactured by Toray Dow Corning Co., Ltd. KR-510 (Si content 20.5% by mass), KR-213 (Si content 17.7% by mass), KR-500 (Si content 29.4% by mass) manufactured by Shin-Etsu Chemical Co., Ltd. , KC-89S (Si content 27.5% by mass), X-40-9225 (Si content 31.3% by mass), X-40-9246 (Si content 33.6% by mass), X-40-9250 (Si content 33.6% by mass) Si content 34.1% by mass), KR-401N (Si content 26.1% by mass), X-40-9227 (Si content 27.5% by mass), X-40-9247 (Si content 21.5% by mass) ), KR-9218 (Si content 18.7% by mass), X-40-2308 (Si content 23.8% by mass), X-40-9238 (Si content 21% by mass) and the like. A desired emulsion can be produced by mixing and stirring these organic silane compounds, water, a surfactant and the like.

As an emulsion containing an organic silane compound or a condensate thereof, a commercially available product can be used. For example, KM-9717 (solid content concentration 60% by mass) manufactured by Shin-Etsu Chemical Co., Ltd., Asahi Kasei Wacker Silicone Co., Ltd. ) Silane (registered trademark) MPF 52E (solid content concentration 60% by mass, SIFCLEAR (registered trademark) S-101 (solid content concentration 40% by mass) manufactured by JSR Co., Ltd., etc. Represents all components except water.

Further, the fluororesin emulsion is obtained, for example, by emulsion polymerization of a fluorine-containing monomer, or by emulsion polymerization of a fluororesin-containing monomer and another monomer that can be polymerized with the fluorine-containing monomer. Things can be mentioned.

Specific examples of the fluorine-containing monomer include fluoroolefins such as vinylidene fluoride, trifluoroethylene, tetrafluoroethylene, pentafluoroethylene, and hexafluoropropylene; trifluoroethyl (meth) acrylate and pentafluoropropyl (meth) acrylate. , Fluorine-containing (meth) acrylate such as perfluorocyclohexyl (meth) acrylate and the like. Specific examples of other monomers that can be polymerized with the fluorine-containing monomer include the above-mentioned acrylic monomer and other monomers that can be polymerized with the acrylic monomer.

Commercially available products can be used as the fluororesin emulsion. For example, Zeffle (registered trademark) SE-700 (solid content concentration 50% by mass) and Zeffle SE-310 (solid content concentration 50% by mass) manufactured by Daikin Industries, Ltd. can be used. %), Zeffle SE-405 (solid content concentration 50% by mass), Asahi Glass Co., Ltd. Lumiflon (registered trademark) FE-4300 (solid content concentration 50% by mass), Lumiflon FE-4400 (solid content concentration 50% by mass) , Lumiflon FE-4500 (solid content concentration 50% by mass) and the like.

The synthetic resin may be used alone or in combination of two or more. In the aqueous synthetic resin emulsion of the present invention, the concentration of the synthetic resin can be appropriately selected from a wide range, but is preferably about 10 to 60% by mass, more preferably about 30 to 50% by mass.

[(B) component]
The component (b) is mica having an average particle size of 0.3 to 3 mm. The average particle size of the mica is preferably 0.4 to 2.5 mm, more preferably 0.5 to 2 mm. If the average particle size is out of the above range, the workability at the time of roller coating is lowered.

Examples of the mica include natural mica such as biotite, muscovite, and phlogopite, synthetic mica, and colored mica artificially colored. The shape of the mica is not particularly limited, but a scaly shape is preferable from the viewpoint of workability.

The content of the component (b) is 3 to 30 parts by mass, preferably 5 to 25 parts by mass, and more preferably 10 to 20 parts by mass with respect to 100 parts by mass of the solid content in the component (a). If the content of the component (b) is out of the above range, the workability at the time of roller coating is lowered. As the mica, a commercially available product can be used.

The mica may be used alone or in combination of two or more, but it is preferable to use two or more in combination from the viewpoint of finishability, for example, artificially coloring. One or more kinds of colored mica and one kind of uncolored one can be used, or one or more kinds of colored mica of different colors can be used.

[Ingredient (c)]
The component (c) is calcium carbonate having an average particle size of 0.1 to 0.5 mm. The average particle size of the calcium carbonate is preferably 0.15 to 0.45 mm, more preferably 0.2 to 0.4 mm. If the average particle size is out of the above range, the workability at the time of roller coating is lowered. As the calcium carbonate, heavy calcium carbonate obtained by crushing limestone and classifying and purifying it is preferable.

The content of the component (c) is 20 to 100 parts by mass with respect to 100 parts by mass of the solid content in the component (a), preferably 30 to 90 parts by mass, and more preferably 50 to 70 parts by mass. If the content of the component (c) is out of the above range, the workability at the time of roller coating is lowered. As the granular calcium carbonate, a commercially available product can be used. The calcium carbonate may be used alone or in combination of two or more.

[(D) component]
If necessary, the aqueous coating composition of the present invention may contain a thickener as the component (d) in order to adjust the viscosity. As the thickener, those known for water-based paints can be used, and specific examples thereof include association-type thickeners, cellulosic thickeners, (meth) acrylic acid-based thickeners, and polyurethanes. Examples thereof include system thickeners, polyacrylamide type thickeners, vinyl ether type thickeners, mineral type thickeners, polysaccharide type thickeners and the like.

Commercially available products can be used as the thickener, for example, ADEKA Corporation's Adecanol (registered trademark) UH series, San Nopco Ltd.'s SN Sixner series, and Toa Synthetic Co., Ltd. Aron (trademark registration). ) Thickener series, BYK (trademark registered) OPTIFLO series, etc. can be mentioned.

The content of the thickener is not particularly limited as long as the composition of the present invention has a viscosity and a Ti value described later, but is usually 0. 3 to 10 parts by mass. The thickener may be used alone or in combination of two or more.

The aqueous coating composition of the present invention has a viscosity of 1,000 to 100,000 mPa · s measured with a B-type viscometer under the conditions of a rotation speed of 20 rpm and a coating temperature of 25 ° C., but is 5,000 to 50,000 mPa. -S is preferable, and 8,000 to 20,000 mPa · s is more preferable. If the viscosity is out of the above range, the workability at the time of roller coating is lowered.

The aqueous coating composition of the present invention has a Ti value (viscosity at a coating temperature of 25 ° C. and a rotation speed of 2 rpm / viscosity at a coating temperature of 25 ° C. and a rotation speed of 20 rpm) of 2 to 8, preferably 3 to 7. 3 to 5 are more preferable. If the Ti value is out of the above range, the workability at the time of roller coating is lowered.

[Other ingredients]
The water-based coating composition of the present invention further comprises a plasticizer, a preservative, an antifungal agent, an algae-proofing agent, an antifoaming agent, a leveling agent, a pigment, a pigment dispersant, an anti-settling agent, an anti-sagging agent, as required. It may contain various additives such as a matting agent, an ultraviolet absorber, a light stabilizer, and a catalyst. As these additives, conventionally known ones can be used. The content of these additives is arbitrary as long as the effect of the composition of the present invention is not impaired, but is usually 0.1 to 30% by mass in the composition of the present invention.

The method for preparing the aqueous coating composition of the present invention is not particularly limited, and the synthetic resin emulsion of the component (a) is mixed with the component (b), the component (c) and, if necessary, other components at the same time or arbitrarily. Add in order, stir and mix.

Examples of the method of using the aqueous coating composition of the present invention include a method of directly applying the composition of the present invention to the surface of a substrate and drying the composition at room temperature. In this case, the coating method of the composition of the present invention is not particularly limited, and may be appropriately selected from known methods such as brush coating, roller coating, and spray coating. Of these, the water-based coating composition of the present invention is suitable for roller coating using a short-haired roller, a medium-haired roller, a long-haired roller, and the like, and is particularly suitable for roller coating using a medium-haired roller. The coating amount, the thickness of the coating film, the drying time, and the like may be appropriately set according to the material of the base material, the application of the coated product, and the like.

Examples of the base material to which the water-based coating composition of the present invention can be applied include mortar, concrete, wood, stone, metal, plastic, glass, siding board and the like. The water-based coating composition of the present invention can be suitably used for coating the inner and outer walls of buildings and structures.

Hereinafter, the present invention will be described in more detail with reference to Synthesis Examples, Examples and Comparative Examples, but the present invention is not limited to the following Examples. The method for measuring the average particle size of mica is as follows.

(1) An average particle size of mica of 150φ JIS test sieve (opening 0.15, 0.3, 0.5, 1, 1.7, 2 mm) was overlapped, and 20 g of a sample was treated with a sieve shaker for 30 seconds. .. After sieving, the average particle size was calculated by dividing the sum of the weight of the sample remaining on each sieve, the opening of the remaining sieve of the sample, and the average of the opening of the sieve overlapping on the sample by the sample amount. ..
(2) Average particle size of calcium carbonate The particle size of 50% cumulative weight in the particle size distribution measured using a sonic vibration type sieving measuring device (Roboshifta RPS-85 type manufactured by Seishin Co., Ltd.) was calculated, and the average particle size. And said.

[Production Example 1] Production of Emulsion Containing Organic Silane Condensate 400 parts by mass of methyl ethyl ketone is charged into a reactor equipped with a stirring device, a thermometer, a cooling tube, a nitrogen gas introduction tube and a dropping device, and the temperature rises to 80 ° C. while stirring. It was warm. A mixture consisting of 270 parts by mass of methyl methacrylate, 185 parts by mass of 2-ethylhexyl acrylate, 30 parts by mass of acrylic acid, 15 parts by mass of dimethylaminoethyl methacrylate, 4 parts by mass of azobisisobutylnitrile and 10 parts by mass of methyl ethyl ketone was added thereto for 3 hours. Dropped over. After completion of the dropping, the reaction was carried out at the same temperature for 1 hour. Further, a mixture consisting of 1 part by mass of azobisisobutylnitrile and 95 parts by mass of methyl ethyl ketone was added dropwise over 1 hour. After completion of the dropping, the mixture was reacted at the same temperature for 1 hour, and the solid content concentration was 50% by mass, the viscosity was 3,200 mPa · s (25 ° C.), the number average molecular weight was 20,000, the solid content amine value was 10.6 mgKOH / g, and the solid content acid. A pale yellow transparent tertiary amino group- and carboxyl group-containing acrylic resin solution (A1) having a value of 46.3 mgKOH / g was obtained.

In addition to the acrylic resin solution (A1), a reactor equipped with a stirrer, thermometer, cooling tube, nitrogen gas introduction tube and dropping device is equipped with polypropylene glycol (trade name: Sanniks PP-1000, Sanyo Kasei Kogyo Co., Ltd.). ) Made: Molecular weight = 1,000) 527.9 parts by mass, 177.8 parts by mass of 1,6-hexamethylene diisocyanate and 200 parts by mass of methyl ethyl ketone were charged, and the temperature was raised to 80 ° C. with stirring in a nitrogen atmosphere. The reaction was carried out at temperature for 6 hours or more. When the isocyanate concentration (NCO%) reached the theoretical amount, 94.3 parts by mass of N, N-dimethylethanolamine was further added, and the reaction was carried out until the isocyanate group disappeared by infrared absorbance analysis. A urethane prepolymer solution (B1) containing a tertiary amino group having a solid content concentration of 80% by mass and a solid content amine value of 74.2 mgKOH / g was obtained.

A reactor equipped with a stirrer, a thermometer, a cooling tube and a dropping device contains 100 parts by mass of a tertiary amino group- and carboxyl group-containing acrylic resin solution (A1) and a methylphenyl-based alkoxysilane compound (trade name: DC3074, Toray. 100 parts by mass of Dow Corning Co., Ltd. and 20 parts by mass of ion-exchanged water were charged and mixed by stirring. Further, 3 parts by mass of dibutyltin laurate was charged with stirring, the temperature was raised to 70 ° C., and the reaction was carried out at the same temperature for 6 hours. After the reaction, the mixture is cooled to 35 ° C., 17.2 parts by mass of a tertiary amino group-containing urethane prepolymer (B1) and 1.9 parts by mass of N, N-dimethylethanolamine are charged and sufficiently neutralized, and then ions are added. 219.5 parts by mass of exchanged water was charged and emulsified. Then, methyl ethyl ketone and methanol produced by the reaction were removed at 60 ° C. and 100 Torr to produce an organic silane condensate-containing emulsion A (solid content concentration: 40.0% by mass, Si content: 16.8% by mass).

[Examples 1 to 7, Comparative Examples 1 to 12]
[1] Preparation of water-based paint composition Each component was charged into a mixing container so as to have the compositions shown in Tables 1 and 2 below, and mixed with a stirrer for 3 minutes to prepare a water-based paint composition. In Tables 1 and 2, each component is as follows.
(A) Ingredients: Synthetic resin-containing emulsion / Organic silane condensate-containing emulsion A: Organic silane condensate-containing emulsion produced in Production Example 1. SE-700: Zeffle SE-700, Fluororesin-containing emulsion manufactured by Daikin Industries, Ltd. , Solid content concentration 50% by mass
(B) Ingredients: Mica / SC30 White: Colored mica manufactured by Hokuto Sangyo Co., Ltd., average particle size 0.15 mm
-SC30 Black: Colored mica manufactured by Hokuto Sangyo Co., Ltd., average particle size 0.15 mm
-SC200 White: Colored mica manufactured by Hokuto Sangyo Co., Ltd., average particle size 1.0 mm
-SC200 Black: Colored mica manufactured by Hokuto Sangyo Co., Ltd., average particle size 1.0 mm
-SC500 White: Colored mica manufactured by Hokuto Sangyo Co., Ltd., average particle size 4.5 mm
-SC500 Black: Colored mica manufactured by Hokuto Sangyo Co., Ltd., average particle size 4.5 mm
(C) Ingredients: Calcium carbonate, G-60: Sandy calcium carbonate manufactured by Sankyo Seiko Co., Ltd., average particle size 0.09 mm
-K-1: Granular calcium carbonate manufactured by Sankyo Seiko Co., Ltd., average particle size 0.3 mm
・ K-3: Granular calcium carbonate manufactured by Sankyo Seiko Co., Ltd., average particle size 0.7 mm
(D) Ingredients: Thickener-UH-752: Adecanol UH-752, manufactured by ADEKA Corporation, polymer-type special nonionic surfactant

[2] Evaluation of water-based coating composition The following evaluation was performed on the water-based coating composition prepared in each Example and Comparative Example. The results are shown in Tables 3 and 4.
(1) Measurement of Viscosity The viscosity was measured at 20 rpm and 2 rpm under 25 ° C. conditions using a Viscometer DV-E manufactured by Brookfield. Further, Ti was calculated from the measured viscosity by the following formula.
Viscosity at Ti = 2 rpm / Viscosity at 20 rpm (2) Workability when applying rollers Use a medium-hair roller (WAKABA manufactured by Otsuka Brush Manufacturing Co., Ltd.) so that the coating amount is 0.2 kg / m ² . It was applied to a flexible board and dried at 50 ° C. to form a coating film. Roller workability was evaluated according to the following criteria.
◯: There is no problem in workability, and mica is not biased after drying.
Δ: There is no problem in workability, but mica is partially biased after drying.
X: Workability is poor, and mica is significantly biased after drying.

Claims (4)

(A) Synthetic resin emulsion,
It contains (b) mica with an average particle size of 0.3 to 3 mm and (c) calcium carbonate with an average particle size of 0.1 to 0.5 mm.
The content of the component (b) is 3 to 30 parts by mass, and the content of the component (c) is 20 to 100 parts by mass with respect to 100 parts by mass of the solid content in the component (a).
The viscosity measured with a B-type viscometer under the conditions of a rotation speed of 20 rpm and a paint temperature of 25 ° C. is 1,000 to 100,000 mPa · s.
A water-based paint composition having a Ti value (viscosity at a paint temperature of 25 ° C. and a rotation speed of 2 rpm / viscosity at a paint temperature of 25 ° C. and a rotation speed of 20 rpm) of 2 to 8. The aqueous coating composition according to claim 1, wherein the synthetic resin emulsion is an emulsion containing an alkoxy group or hydroxyl group-containing organic silane compound represented by the following formula (1) or a condensate thereof, and / or a fluororesin.

(In the formula, R ¹ is a hydrogen atom or an alkyl group, and R ^{2 to} R ⁴ are independently a hydrogen atom, −OR ¹ , an alkyl group or an aryl group.) The aqueous coating composition according to claim 1 or 2, further comprising (d) a thickener. The water-based coating composition according to any one of claims 1 to 3, which is used for coating a medium-hair roller.