JP2011219653A - Coating composition for surface coating of blade of wind power generator, blade of wind power generator, and method for manufacturing the blade - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coating composition for surface coating of a blade of a wind power generator, for forming a coating film excellent in weather resistance and slipping property for snow and ice and contamination removing property on a blade surface of a wind power generator, and to provide the blade and a method for manufacturing the blade.SOLUTION: The coating composition for a blade of a wind power generator contains a fluorocarbon resin having a hydrolyzable silyl group as an essential component. The blade of a wind power generator has a coating film on the surface of a blade base, the coating film being formed of the above described coating composition for surface coating of a blade of a wind power generator. The method for manufacturing the blade is also disclosed.

Description

  The present invention relates to a wind power generator blade surface coating composition, a wind power generator blade and a method of manufacturing the same.

  Wind power generators have been popularized in various places because clean energy can be obtained. Such a wind power generator is generally installed in a place where strong winds blow for a long time, and is often installed especially on a coastline where there are no high buildings or trees in the vicinity. As a wind power generator, for example, as shown in FIG. 2, a tower body 110, a tower top turning part 120 provided on the tower body 110, and a tower top turning part 120 via a turning support part. And a wind power generator 101 having a blade 130 attached thereto. The tower top rotating section 120 rotates according to the wind direction, and the blade 130 is directed toward the direction where the wind is blowing. As the blade 130, for example, a blade in which the surface of a wing-like plate piece made of wood is reinforced with fiber reinforced plastic (FRP) is used.

A wind power generator installed in a cold region has a problem that snow and ice adhere to the blade, and wind turbine efficiency and power generation efficiency decrease due to an increase in wind resistance.
In particular, when snow and ice contain a very small amount of water, the snow and ice grow to a considerably large weight due to hydrogen bonding force, van der Waals force and the like derived from water, and windmill efficiency and power generation efficiency are greatly reduced.
Although it is effective to incorporate a heating element such as a heater into the blade or tower as a measure to prevent snow accretion, it cannot be said that the addition of equipment is cheap, and the cost required to maintain energy such as electric power and equipment And the effort is extremely large. There is also a problem that water generated by the melted snow and ice freezes again at a location away from the heating element.
Physically, a method of wiping off snow-covered ice is also conceivable. However, snow and ice that adheres firmly cannot be wiped out sufficiently, and in a recent 1500 kW class wind power generator, the rotation axis of the windmill blade is 70 meters above the sky. Therefore, since the total length of the windmill blade exceeds 30 m, it is difficult to wipe off the snow-covered ice even if the crane work is taken into consideration.

As a method for preventing snow accretion and icing, members coated with water-repellent paints and outdoor workpieces have been proposed (Patent Documents 1 to 3). These occur between snow and ice and the outer surface of the coating layer, and try to prevent snow accretion and icing by minimizing the hydrogen bonds and van der Waals forces that cause snow accretion. To do.
However, these outdoor workpieces, when installed outdoors, can provide good snow and ice prevention effects at the beginning of installation, but their water repellency decreases due to deterioration of the coating layer itself several years after installation, The effect of preventing snow accretion is lost.

  On the other hand, in order to prevent deterioration of the coating layer, a method of applying a highly weather-resistant fluorine paint to the surface of the blade has been proposed (Patent Document 4). However, the paint component is mainly composed of a hydroxyl group-containing fluoropolymer and an isocyanate curing agent, and the water repellency of the coating layer is not so high, and an effect of preventing snow accretion cannot be expected. In addition, dirt (for example, dust in the atmosphere, dead carcasses of insects, etc.) easily enters the coating film, and removal thereof is not easy.

JP 2002-370317 A JP-A-10-310740 International Publication No. 02/092945 Pamphlet US Patent Application Publication No. 2009/0220795

An object of the present invention is to provide a coating composition for coating the surface of a blade of a wind power generator capable of forming a coating film excellent in weather resistance, snow-sliding ice property and decontamination property as a coating layer provided on the blade surface of the wind power generator. And
Another object of the present invention is to provide a blade of a wind power generator having a coating film excellent in weather resistance, snow-sliding ice property, and decontamination property, and a manufacturing method thereof.

The present invention employs the following configuration in order to solve the above problems.
[1] A coating composition for coating a surface of a blade of a wind power generator, comprising the fluoropolymer (A) having a hydrolyzable silyl group as an essential component.
[2] The fluoropolymer (A) having a hydrolyzable silyl group is a fluoropolymer having a repeating unit (A1) based on a fluoroolefin and a repeating unit (A2) having a hydrolyzable silyl group. [1] The coating composition for surface coating of a blade of a wind power generator according to [1].
[3] The repeating unit (A2) having the hydrolyzable silyl group is a repeating unit (A2-1) having a group represented by the following formula (1), according to [1] or [2] A coating composition for wind turbine blade surface coating.
—OC (O) NH (CH ₂ ) _m SiX ¹ _n R ¹ _3-n (1)
(Wherein R ¹ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms, X ¹ is an alkoxy group having 1 to 5 carbon atoms, n is an integer of 1 to 3, and m is an integer of 1 to 5) Show.)
[4] Any one of [1] to [3], wherein the fluoroolefin is one or more selected from the group consisting of tetrafluoroethylene, chlorotrifluoroethylene, hexafluoropropylene, vinylidene fluoride, and vinyl fluoride. Item 2. A coating composition for surface coating of a blade of a wind power generator according to item 2.
[5] A fluorine paint containing a hydrolyzable silyl group-containing fluorine-containing polymer (A) as an essential component comprises the following curing agent (B), phosphate ester-based curing catalyst (C1), and organic solvent (D). The coating composition for surface coating of a blade of a wind power generator according to any one of [1] to [4], comprising:
Curing agent (B): a compound represented by the following formula (2) and / or a partial hydrolysis-condensation product thereof.
SiX ² _a R ² _4-a (2)
(Wherein R ² represents a monovalent hydrocarbon group having 1 to 10 carbon atoms, X ² represents an alkoxy group having 1 to 10 carbon atoms, and a represents an integer of 2 to 4)
[6] The coating composition for coating a surface of a blade of a wind power generator according to any one of [1] to [5], further comprising titanium oxide.
[7] A wind power generator that applies a coating composition for coating the surface of a blade of the wind power generator according to any one of [1] to [6] to form a coating layer on the surface of the blade base to cure the wind power generator. Blade manufacturing method.
[8] A blade of a wind power generator having a coating film formed from the coating composition for surface coating of a blade of the wind power generator according to any one of [1] to [6] on a blade base surface.

The coating composition for coating a blade surface of a wind power generator of the present invention can form a coating film excellent in weather resistance, snow-sliding ice property, and decontamination property as a coating layer provided on the blade surface of the wind power generator.
Further, the blade of the wind power generator of the present invention has a coating film excellent in weather resistance, snow-sliding ice property and decontamination property. Furthermore, according to the production method of the present invention, it is possible to easily produce a blade of a wind power generator having a coating film excellent in weather resistance, snow-sliding ice property and contamination removal property.

It is the fragmentary sectional view showing an example of the embodiment of the blade of the wind power generator of the present invention. It is the schematic diagram which showed an example of the wind power generator.

In the present specification, a repeating unit formed directly by polymerization of a monomer and a repeating unit obtained by chemically converting a part of the repeating unit formed by polymerization of the monomer are collectively referred to as “polymerized unit”. "Or" unit ".
Moreover, description with (meth) acrylic acid is a general term for acrylic acid and methacrylic acid.

<Coating composition for wind turbine blade surface coating>
The wind power generator blade surface coating composition of the present invention (hereinafter also simply referred to as “coating composition”) is a coating composition that is applied to the wind power generator blade surface to form a coating film. Thus, a fluorine-containing polymer having a hydrolyzable silyl group is an essential component. By forming the coating film with a coating composition containing a hydropolymer having a hydrolyzable silyl group, the weather resistance, snow-sliding ice property and decontamination property of the blade of the wind power generator are improved.

  The fluorine-containing polymer (A) having a hydrolyzable silyl group contained in the coating composition of the present invention (hereinafter also referred to as “fluorine-containing polymer (A)”) has a polymer unit based on a fluoroolefin. A polymer is preferred.

[Fluoropolymer (A)]
The fluoropolymer (A) in the present invention is a fluoropolymer having a hydrolyzable silyl group. The fluoropolymer (A) is preferably a fluoropolymer having a unit (A1) based on a fluoroolefin and a unit (A2) having an alkoxysilyl group. Moreover, the fluoropolymer may have other units (A3) other than the unit (A1) and the unit (A2) as an optional component.

[Unit (A1)]
The unit (A1) is a unit based on a fluoroolefin. 2-8 are preferable and, as for carbon number of a fluoro olefin, 2-6 are more preferable. The number of fluorine atoms in the fluoroolefin (hereinafter referred to as “fluorine addition number”) is preferably 2 or more, and more preferably 3-4. When the fluorine addition number is 2 or more, the weather resistance of the coating film is improved, and the snow-ice property can be maintained for a long time. In the fluoroolefin, one or more hydrogen atoms not substituted with fluorine atoms may be substituted with chlorine atoms.

As the fluoroolefin, one or more selected from the group consisting of tetrafluoroethylene, chlorotrifluoroethylene, hexafluoropropylene, vinylidene fluoride and vinyl fluoride is preferable, and tetrafluoroethylene and chlorotrifluoroethylene are more preferable.
A fluoro olefin may be used individually by 1 type, and may use 2 or more types together.
As the unit (A1) based on fluoroolefin, a polymer unit directly formed by polymerizing fluoroolefin is preferable.

[Unit (A2)]
The unit (A2) is a unit having a hydrolyzable silyl group, and the hydrolyzable silyl group is preferably an alkoxysilyl group.
The unit (A2) is preferably a unit having an alkoxysilyl group, and examples of the unit (A2) include the following unit (A2-1) and unit (A2-2).
Unit (A2-1): a unit formed by reacting a compound having an isocyanate group and a hydrolyzable silyl group with a unit based on a monomer having a hydroxyl group.
Unit (A2-2): A unit based on a monomer having a hydrolyzable silyl group.

[Unit (A2-1)]
The unit (A2-1) is a unit obtained by a reaction between a hydroxyl group of a unit based on a monomer having a hydroxyl group and a compound having an isocyanate group and a hydrolyzable silyl group.

The monomer having a hydroxyl group is a compound having a hydroxyl group and a polymerizable reactive group. The polymerizable reactive group is preferably an ethylenically unsaturated group such as a vinyl group, an allyl group, or a (meth) acryloyl group. Examples of the monomer having a hydroxyl group include 2-hydroxyethyl vinyl ether, 3-hydroxypropyl vinyl ether, 2-hydroxypropyl vinyl ether, 2-hydroxy-2-methylpropyl vinyl ether, 4-hydroxybutyl vinyl ether, 4-hydroxy-2-methyl. Hydroxyalkyl vinyl ethers such as butyl vinyl ether, 5-hydroxypentyl vinyl ether and 6-hydroxyhexyl vinyl ether; ethylene glycol monovinyl ethers such as diethylene glycol monovinyl ether, triethylene glycol monovinyl ether and tetraethylene glycol monovinyl ether; hydroxyethyl allyl ether, hydroxy Butyl allyl ether, 2-hydroxyethyl allyl ether Hydroxyalkyl allyl ethers such as 4-hydroxybutyl allyl ether and glycerol monoallyl ether; Hydroxyalkyl vinyl esters such as hydroxyethyl vinyl ester and hydroxybutyl vinyl ester; Hydroxyalkyl allyl such as hydroxyethyl allyl ester and hydroxybutyl allyl ester Esters; (meth) acrylic acid hydroxyalkyl esters such as hydroxyethyl (meth) acrylate and the like.
The monomer which has a hydroxyl group may be used individually by 1 type, and may use 2 or more types together.

As the compound having an isocyanate group and a hydrolyzable silyl group, a compound represented by the following formula (1a) (hereinafter referred to as “compound (1a)”) is preferable.
OCN (CH ₂ ) _m SiX ¹ _n R ¹ _3-n (1a)
(In the formula (1a), R ¹ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms, X ¹ is an alkoxy group having 1 to 5 carbon atoms, n is an integer of 1 to 3, and m is Represents an integer of 1 to 5.)

R ¹ in the compound (1a) is a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms. If the carbon number of the monovalent hydrocarbon group in R ¹ is 10 or less, the compound (1a) is prevented from becoming too bulky, so that the condensation reaction of the alkoxy group (X ¹ ) during curing of the coating film It is easy to suppress the difficulty of proceeding due to steric hindrance. Therefore, the curability of the coating film is improved, and excellent weather resistance, chemical resistance, snow-sliding ice properties, decontamination property, scratch resistance and impact resistance are easily obtained.
R ¹ is preferably a monovalent hydrocarbon group having 1 to 10 carbon atoms, preferably a monovalent hydrocarbon group having 1 to 5 carbon atoms, and preferably a methyl group or an ethyl group.
X ¹ is an alkoxy group having 1 to 5 carbon atoms, preferably an ethoxy group or a methoxy group. When the number of carbon atoms in the X ¹ is 5 or less, the alcohol component is easily volatilized caused by crosslinking reaction between below the curing agent (B). For this reason, it is easy to prevent the alcohol component from remaining in the cured coating film and lowering the weather resistance, chemical resistance, snow slidability, decontamination, scratch resistance and impact resistance.
n is an integer of 1 to 3, and 3 is preferable.
m is an integer of 1-5, and 2-4 are more preferable.

Specific examples of the compound (1a) include 3-isocyanatopropyltrimethoxysilane (X ¹ = methoxy group, n = 3, m = 3), 3-isocyanatopropyltriethoxysilane (X ¹ = ethoxy group, n = 3). , M = 3), 3-isocyanatopropylmethyldimethoxysilane (X ¹ = methoxy group, R ¹ = methyl group, n = 2, m = 3), 3-isocyanatopropylmethyldiethoxysilane (X ¹ = ethoxy group, R ¹ = methyl group, n = 2, m = 3), 3-isocyanatopropyldimethylmethoxysilane (X ¹ = methoxy group, R ¹ = methyl group, n = 1, m = 3), 3-isocyanatopropyldimethylethoxy Silane (X ¹ = ethoxy group, R ¹ = methyl group, n = 1, m = 3), 4-isocyanatobutyltrimethoxysilane (X ¹ = Methoxy group, n = 3, m = 4), 4-isocyanatobutyltriethoxysilane (X ¹ = ethoxy group, n = 3, m = 4), 2-isocyanatoethyltrimethoxysilane (X ¹ = methoxy group, n = 3, m = 2), 2-isocyanatoethyltriethoxysilane (X ¹ = ethoxy group, n = 3, m = 2) and the like.
As the compound (1a), 3-isocyanatopropyltrimethoxysilane and 3-isocyanatopropyltriethoxysilane are preferable from the viewpoint of availability.
As the compound (1a), one type may be used alone, or two or more types may be used in combination.

A urethane bond (—NHC (═O) —) is formed by a reaction between a hydroxyl group of a unit based on a monomer having a hydroxyl group and an isocyanate group of the compound (1a), and has a group represented by the following formula (1). Unit (A2-1) is formed.
^{_{-ONHC (= O) (CH 2}} ) m SiX 1 n R 1 3-n ··· (1)
(In the formula (1), R ¹ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms, X ¹ is an alkoxy group having 1 to 5 carbon atoms, n is an integer of 1 to 3, m is Represents an integer of 1 to 5.)

The reaction between the hydroxyl group of the unit based on the monomer having a hydroxyl group and the isocyanate group of the compound (1a) is a solvent having no active hydrogen that reacts with the isocyanate group of the compound (1a) (for example, ethyl acetate, methyl ethyl ketone, xylene, etc. .) Is preferable.
The ratio of the compound (1a) to the hydroxyl group of the unit based on the monomer having a hydroxyl group is preferably 0.1 to 10 mol, preferably 0.5 to 5 mol, per mol of the hydroxyl group. It is more preferable. If compound (1a) is 0.1 mol or more with respect to 1 mol of hydroxyl groups, the amount of the alkoxysilyl group will increase, and curing at the time of coating film formation will easily proceed. If the amount of the compound (1) is 10 mol or less with respect to 1 mol of the hydroxyl group, it is easy to suppress a large amount of unreacted compound (1) remaining in the coating film. , Improved snow sliding, decontamination, scratch resistance and impact resistance.

  The reaction between the hydroxyl group of the unit based on the monomer having a hydroxyl group and the isocyanate group of the compound (1a) can be carried out in a yield of almost 100%. However, in order to further increase the reaction rate, the compound (1a) is in an excessive state. You may make it react.

  The reaction temperature of the reaction between the hydroxyl group of the unit based on the monomer having a hydroxyl group and the isocyanate group of the compound (1a) is preferably room temperature to 100 ° C, more preferably 50 to 70 ° C. The reaction is preferably performed in an inert atmosphere such as a nitrogen atmosphere. The reaction time can be appropriately changed according to the progress of the reaction, and is preferably 1 to 24 hours, more preferably 3 to 8 hours. In the reaction system, an organic metal catalyst such as an organic tin compound, an organic aluminum compound, an organic zirconium compound, or an organic titanate compound is preferably present for the purpose of promoting the reaction.

[Unit (A2-2)]
The monomer forming the unit (A2-2) is a monomer having a hydrolyzable silyl group. The hydrolyzable silyl group is preferably an alkoxysilyl group. The polymerizable reactive group in the monomer having a hydrolyzable silyl group is preferably an ethylenically unsaturated group such as a vinyl group, an allyl group, or a (meth) acryloyl group.

The monomers forming the units _{(A2-2), CH 2 = CHCO} 2 (CH 2) 3 Si (OCH 3) 3, CH 2 = CHCO 2 (CH 2) 3 Si (OC 2 H 5) 3, CH _{2 = C (CH 3) CO} 2 (CH 2) 3 Si (OCH 3) 3, CH 2 = C (CH 3) CO 2 (CH 2) 3 Si (OC 2 H 5) 3, CH 2 = CHCO 2 _{(CH 2) 3 SiCH 3 (} OC 2 H 5) 2, CH 2 = C (CH 3) CO 2 (CH 2) 3 SiC 2 H 5 (OCH 3) 2, CH 2 = C (CH 3) CO 2 _{(CH 2) 3 Si (CH} 3) 2 (OC 2 H 5), CH 2 = C (CH 3) CO 2 (CH 2) 3 Si (CH 3) 2 OH, CH 2 = CH (CH 2) 3 _{Si (OCOCH 3) 3, CH} 2 = C _{CH 3) CO 2 (CH 2} ) 3 SiC 2 H 5 (OCOCH 3) 2, CH 2 = C (CH 3) CO 2 (CH 2) 3 SiCH 3 (N (CH 3) COCH 3) 2, CH 2 _{= CHCO 2 (CH 2) 3} SiCH 3 [ON (CH 3) C 2 H 5] 2, CH 2 = C (CH 3) CO 2 (CH 2) 3 SiC 6 H 5 [ON (CH 3) C 2 Acrylic acid esters or methacrylic acid esters such as H ₅ ] ₂ ; CH ₂ = CHSi [ON = C (CH ₃ ) (C ₂ H ₅ )] ₃ , CH ₂ = CHSi (OCH ₃ ) ₃ , CH ₂ = CHSi (OC ₂ H ₅ ) ₃ , CH ₂ = CHSiCH ₃ (OCH ₃ ) ₂ , CH ₂ = CHSi (OCOCH ₃ ) ₃ , CH ₂ = CHSi (CH ₃ ) ₂ (OC ₂ H ₅ ), CH ₂ = _{CHSi (CH 3) 2 SiCH 3} (OCH 3) 2, CH 2 = CHSiC 2 H 5 (OCOCH 3) 2, CH 2 = CHSiCH 3 [ON (CH 3) C 2 H 5] 2, vinyl trichlorosilane or their Silanes such as partial hydrolysates of vinyl; vinyl ethers such as trimethoxysilylethyl vinyl ether, triethoxysilylethyl vinyl ether, trimethoxysilylbutyl vinyl ether, methyldimethoxysilylethyl vinyl ether, trimethoxysilylpropyl vinyl ether, triethoxysilylpropyl vinyl ether, etc. Is mentioned.

Moreover, as a monomer which forms a unit (A2-2), the monomer (a) which has the alkoxy silyl group obtained by reacting the hydroxyl group of the monomer which has a hydroxyl group, and the isocyanate group of the said compound (1a) is also preferable.
As the monomer having a hydroxyl group used for obtaining the monomer (a) having an alkoxysilyl group, the same monomer as the monomer having a hydroxyl group used for forming the unit (A2-1) can be used.
Moreover, it is the same as the preferable aspect of the compound (1a) at the time of forming a unit (A2-1) also about the preferable aspect of a compound (1a).
The reaction conditions between the hydroxyl group of the monomer having a hydroxyl group and the isocyanate group of the compound (1a) are as follows: the unit hydroxyl group and the compound (1a) based on the monomer having a hydroxyl group when the unit (A2-1) is formed. The reaction can be performed under the same conditions as the reaction with an isocyanate group, and preferable conditions are also the same.

The unit (A2) may have a fluorine atom. That is, one or more hydrogen atoms bonded to the carbon atoms constituting the unit (A2) may be substituted with fluorine atoms.
The unit (A2) contained in the fluoropolymer (A) may be one type or two or more types.

  The unit (A2) is a unit formed from the unit (A2-1) or the monomer (a) having an alkoxysilyl group because the adhesion to the substrate is improved when a urethane bond is present in the unit (A2). It is preferable that it is (A2-2). Furthermore, the unit (A2) is more preferably a unit (A2-1) from the viewpoint of ease of production.

[Unit (A3)]
The fluoropolymer (A) in the present invention may have other units (A3) as optional components in addition to the units (A1) and the units (A2). Hereinafter, the monomer that forms the unit (A3) by polymerization is referred to as another monomer.

Since the effect of improving the adhesion between the coating film on the blade of the wind power generator and the blade substrate on which the coating film is formed is expressed, other monomers include vinyl ethers, vinyl esters, and allyl ethers. preferable.
Other specifically preferred monomers include vinyl esters such as vinyl acetate, vinyl pivalate and vinyl benzoate; vinyl ethers such as ethyl vinyl ether, butyl vinyl ether, 2-ethylhexyl vinyl ether and cyclohexyl vinyl ether; ethyl allyl ether, Examples include allyl ethers such as butyl allyl ether and cyclohexyl allyl ether.

Further, from the viewpoint of improving the solubility in a solvent, olefins such as ethylene and isobutylene may be used as other monomers.
Another monomer may be used individually by 1 type and may use 2 or more types together.

  Since the unit (A3) is an optional component, the fluoropolymer (A) is a polymer comprising the unit (A1) and the unit (A2), or the unit (A1), the unit (A2) and the unit (A3). At least one of the polymers consisting of can be used.

The content of the unit (A1) in the fluoropolymer (A) is preferably from 5 to 95 mol%, preferably from 10 to 90 mol%, based on the total content of the unit (A1) and the unit (A2). More preferred. If the said content of a unit (A1) is 5 mol% or more, the weather resistance of the coating film formed will improve. When the content of the unit (A1) is 95 mol% or less, the compatibility with the curing agent (B) described later is good, and a dense coating film can be formed during curing. , Weather resistance, chemical resistance, snow slidability, decontamination, scratch resistance and impact resistance are improved.
The content of the unit (A2) in the fluoropolymer (A) is preferably from 5 to 95 mol%, more preferably from 10 to 90 mol%, based on the total content of the unit (A1) and the unit (A2). More preferred. If the content of the unit (A2) is 5 mol% or more, the crosslinking density with the curing agent (B) described later is increased, and a dense coating film can be formed during the curing. The weather resistance, chemical resistance, snow-sliding ice property, decontamination property, scratch resistance and impact resistance of the coating film are improved. Further, the compatibility between the fluoropolymer (A) and the curing agent (B) described later becomes better, and it becomes easier to form a uniform coating film. If the said content of a unit (A2) is 95 mol% or less, stability of a fluoropolymer (A) will improve and the pot life of a coating composition will improve.
From the viewpoint of weather resistance, the content of the unit (A1) in the fluoropolymer (A) is preferably from 5 to 95 mol% based on the total of all units in the fluoropolymer (A). 90 mol% is more preferable, and 15 to 85 mol% is most preferable.
In addition, the content of the unit (A2) in the fluoropolymer (A) increases the weatherability, chemical resistance, snow slidability, decontamination, and scratch resistance of the cured coating film by increasing the crosslinkability. From the viewpoint of improving impact resistance, the total amount of all units in the fluoropolymer (A) is preferably 1 to 80 mol%, more preferably 3 to 70 mol%, most preferably 5 to 60 mol%. preferable.

The content of the unit (A3) in the fluoropolymer (A) is preferably from 0 to 60 mol%, more preferably from 0 to 50 mol%, based on the total of all units in the fluoropolymer (A). . The unit (A3) is an optional component, and the content of the unit (A3) being 0 mol% means that the unit (A3) is not included. When the unit (A3) is contained, the lower limit of the content is more than 0 mol%, and preferably 0.5 mol%. If content of a unit (A3) is 60 mol% or less, it will become easy to improve adhesiveness with a blade base | substrate, without reducing the weather resistance of a coating film.
The content of each unit in the fluoropolymer (A) can be controlled by the amount of each monomer charged and the reaction conditions in the polymerization reaction for obtaining the fluoropolymer (A).

[Method for Producing Fluoropolymer (A1)]
As a manufacturing method of a fluoropolymer (A1), the following method (x1) and method (x2) are preferable.
Method (x1): A method of reacting the isocyanate group of the compound (1a) with the hydroxyl group of the obtained polymer after copolymerizing a monomer having a hydroxyl group, a fluoroolefin, and a monomer used as necessary.
Method (x2): A method of copolymerizing a fluoroolefin, a monomer having an alkoxysilyl group, and a monomer used as necessary.
Method (x1) is a method for producing a fluoropolymer (A) having units (A2-1), and method (x2) is a method for producing a fluoropolymer (A) having units (A2-2). is there.

Method (x1):
The method (x1) includes the following step (x1-1) and step (x1-2).
Step (x1-1): A step of copolymerizing a monomer having a hydroxyl group, a fluoroolefin, and, if necessary, the other monomer.
Step (x1-2): A step of reacting the isocyanate group of the compound (1a) with the hydroxyl group of the polymer obtained in the step (x1-1).
Hereinafter, an example of the process (x1-1) and the process (x1-2) will be described for the method (x1).

In the step (x1-1), the copolymerization of the fluoroolefin, the monomer having a hydroxyl group, and other monomers used as necessary can employ a known radical polymerization method, and the polymerization forms include solution polymerization and suspension polymerization. Emulsion polymerization or the like can be employed.
Although the reaction temperature at the time of superposition | polymerization changes also with the radical polymerization initiator to be used, 0-130 degreeC is preferable. The reaction time is preferably 1 to 50 hours.
Examples of the solvent include ion-exchanged water; alcohol solvents such as ethanol, butanol and propanol; saturated hydrocarbon solvents such as n-hexane and n-heptane; aromatic hydrocarbon solvents such as toluene and xylene; methyl ethyl ketone Ketone solvents such as cyclohexanone; ester solvents such as ethyl acetate and butyl acetate can be used.

  Examples of the radical polymerization initiator include peroxydicarbonates such as diisopropyl peroxydicarbonate and di-n-propyl peroxydicarbonate; and peroxydicarbonates such as t-hexyl peroxypivalate and t-butyl peroxypivalate. Oxyesters; Ketone peroxides such as cyclohexanone peroxide and methyl ethyl ketone peroxide; 1,1-bis (t-hexylperoxy) cyclohexane, 1,1-bis (t-butylperoxy) cyclohexane, etc. Peroxyketals; peroxycarbonate esters such as t-hexylperoxy-n-butyl carbonate and t-butylperoxy-n-propyl carbonate; diacyl peroxides such as isobutyryl peroxide and lauroyl peroxide Earth; dicumyl peroxide, dialkyl peroxides such as di -t- butyl peroxide and the like can be used.

In the case of emulsion polymerization, the polymerization can be carried out in water and in the presence of an anionic or nonionic emulsifier using an initiator such as a water-soluble peroxide, a persulfate, or a water-soluble azo compound.
Since a trace amount of hydrochloric acid or hydrofluoric acid may be generated during the polymerization reaction, it is preferable to add a buffer in advance during the polymerization.
The monomer having a hydroxyl group used in the step (x1-1) can be the same as the monomer having a hydroxyl group used in the formation of the unit (A2-1).

  In the step (x1-2), the reaction between the hydroxyl group of the polymer obtained in the step (x1-1) and the isocyanate group of the compound (1a) is a reaction condition for forming the unit (A2-1). The same conditions can be adopted, and preferred embodiments are also the same.

  Since the method (x1) allows easy control of the reaction, the fluorinated copolymer (A) is preferably produced by the method (x1).

Method (x2):
For the copolymerization in the method (x2), the same radical polymerization method as in the step (x1-1) can be employed. The monomer having an alkoxysilyl group used in the method (x2) is preferably the same as the monomer forming the unit (A2-2), and the monomer (a) having the alkoxysilyl group is more preferable.
About manufacture of the monomer (a) which has an alkoxy silyl group, it is as having described in description of the unit (A2-2). As described above, the reaction between the hydroxyl group of the unit based on the monomer having a hydroxyl group and the isocyanate group of the compound (1a) may be allowed to react in a situation where the compound (1a) is excessive. In that case, after removing the compound (1a) from the reaction product, the polymerization reaction may be carried out to produce the fluoropolymer (A). The reaction product contains the unreacted compound (1a). The fluoropolymer (A) may be produced by carrying out the polymerization reaction as it is.

  In addition, the manufacturing method of a fluoropolymer (A) is not limited to the method (x1) and (x2) mentioned above. For example, trade name “Lumiflon” (Asahi Glass Co., Ltd.), trade name “Fluonate” (Dainippon Ink Chemical Co., Ltd.), trade name “Cefral Coat” (Central Glass Co., Ltd.), trade name “Zaflon” (Toa Gosei Co., Ltd.) ), A fluorine-containing polymer (A) having an alkoxysilyl group may be produced by reacting the compound (1a) with a commercially available fluororesin such as a trade name “Zeffle” (manufactured by Daikin Industries).

[Curing agent (B)]
The curing agent (B) reacts with the hydrolyzable silyl group of the fluoropolymer (A) to form a crosslinked structure, thereby curing the coating layer formed by coating the coating composition, To play a role.
As the curing agent (B), a compound represented by the following formula (2) (hereinafter referred to as “compound (2)”) is preferable.
SiX ² _a R ² _4-a (2)
(In said formula (2), R < ² > is respectively independently a C1-C10 monovalent hydrocarbon group, X < ² > is a C1-C10 alkoxy group, a shows the integer of 2-4. )

The monovalent hydrocarbon group for R ² may have a substituent. That is, part or all of the hydrogen atoms of the monovalent hydrocarbon group of R ² may be substituted with a substituent. The substituent is preferably a halogen atom, more preferably a fluorine atom.
R ² is preferably a methyl group, an ethyl group, a hexyl group, a decyl group, a phenyl group, or a trifluoropropyl group. When ^two or more R < ² > exists in a compound (2), it is preferable that several R < ² > is mutually the same from the point of the supply property of a raw material. However, several R < ² > may mutually differ.
X ² is an alkoxy group having 1 to 10 carbon atoms, preferably a methoxy group or an ethoxy group, and particularly preferably a methoxy group. X ² a plurality present in the compound (2) is, from the viewpoint of easily uniformly formed reactive coating film is the same alkoxy group, it is preferably a plurality of X ² are the same to each other. However, a plurality of X ² may be different from each other.
A in a compound (2) is an integer of 2-4, and 3-4 are preferable.

Specific examples of the compound (2) include tetrafunctional alkoxysilanes such as tetramethoxysilane, tetraethoxysilane, and tetraisopropoxysilane; methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, Trifunctional alkoxysilanes such as hexyltrimethoxysilane, hexyltriethoxysilane, decyltrimethoxysilane, and trifluoropropyltrimethoxysilane; bifunctional such as dimethyldimethoxysilane, diphenyldimethoxysilane, dimethyldiethoxysilane, and diphenyldiethoxysilane And functional alkoxysilanes. Of these, tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, and phenyltrimethoxysilane are preferable from the viewpoint of curing speed and physical properties of the resulting coating film.
A compound (2) may be used individually by 1 type, and may use 2 or more types together.

Compound (2) may be used as a partially hydrolyzed condensate obtained by partial hydrolysis and condensation. The partial hydrolysis-condensation product is a compound obtained by condensing the compound (2) by partial hydrolysis so that two or more hydrolyzable groups (—OR ³ groups) remain in the molecule. It is. Although the overall structure of the partially hydrolyzed condensate is not clear, it is a polysilicate ester composed of a skeleton composed of —Si—O— bonds and an alkoxy group, and the skeleton may be linear or branched. It may be a chain or a cyclic structure.
The partially hydrolyzed condensate of compound (2) is more preferable as the degree of condensation is lower. The lower the degree of condensation of the partially hydrolyzed condensate, the better the compatibility with the fluoropolymer (A). In addition, the thermal expansion coefficient between the coating film to be formed and the blade base becomes closer, and peeling of the coating film from the blade base due to expansion and contraction due to heat hardly occurs.

  The method for producing the partially hydrolyzed condensate of compound (2) is not particularly limited, and known methods for producing partially hydrolyzed condensates can be employed. For example, the method of adding at least 1 sort (s) of water, an acid, and a solvent to a compound (2), and making it partially hydrolyze-condensate is mentioned.

As the partially hydrolyzed condensate of compound (2), those having different condensation degrees, structures, and types of alkoxy groups are commercially available. For example, trade names “MKC silicate MS51”, “MKC silicate MS56” (and above, Mitsubishi). Chemicals), trade names “M silicate 51”, “ethyl silicate 40”, “ethyl silicate 45” (above, manufactured by Tama Chemical Industry Co., Ltd.) and the like, and a condensate having an effective silica content of about 28 to 52% by mass, Alternatively, trade names “HAS-1”, “HAS-6”, “HAS-10” (manufactured by Colcoat Co., Ltd.) in which the condensate is dissolved in ethanol or isopropanol are listed. The “effective silica content” is a value indicating the content of silica in terms of SiO ₂ when the polyalkyl silicate contained in the product is 100% by mass.
The partial hydrolysis-condensation product of compound (2) may be used individually by 1 type, and may use 2 or more types together.

As the curing agent (B), aluminum alkoxide such as aluminum isopropoxide (Al [O—CH (CH ₃ ) ₂ ] ₃ ), or titanium such as titanium butoxide (Ti (O—C ₄ H ₉ ) ₄ ). Alkoxides can also be used.

  When the coating composition of the present invention uses the fluoropolymer (A) and the curing agent (B), the coating composition does not contain the curing agent (B), and the curing agent (B) is added immediately before forming the coating film. A two-component coating composition may be added, or a one-component coating composition containing both the fluoropolymer (A) and the curing agent (B). Furthermore, since the alkoxysilyl groups in the fluoropolymer (A) cause a condensation reaction, in that case, the curing agent (B) may not necessarily be contained.

When the coating composition of the present invention uses a fluoropolymer (A) and a curing agent (B), the content of the fluoropolymer (A) when used is the same as that of the fluoropolymer (A) and curing. 10-90 mass% is preferable with respect to the sum total of content of an agent (B), 20-80 mass% is more preferable, 30-70 mass% is further more preferable.
If the said content of a fluoropolymer (A) is 10 mass% or more, the weather resistance of a coating film, snow-sliding ice property, and decontamination will improve. If the said content of a fluoropolymer (A) is 90 mass% or less, it will be easy to suppress that a crack generate | occur | produces in a coating film, and the adhesiveness of a coating film and a blade base | substrate will improve.

[Curing catalyst (C)]
The coating composition of the present invention, when using the fluoropolymer (A) and the curing agent (B), accelerates the curing reaction and imparts good chemical performance and physical performance to the coating film that is a cured product. For the purpose, a curing catalyst (C) may be contained. In particular, when curing at a low temperature in a short time, it is preferable to contain a curing catalyst (C). Examples of the curing catalyst (C) include acidic phosphoric acid esters such as phosphoric acid monoester and phosphoric acid diester (hereinafter referred to as “phosphoric acid ester curing catalyst (C1)”), boric acid monoester, boric acid. Acid borate esters such as diesters; amine adducts such as addition reaction products of acid phosphate esters and amines; addition reaction products of carboxylic acid compounds and amines; metal esters such as tin octylate and dibutyltin dilaurate Metal chelates such as tris (acetylacetonate) aluminum and tetrakis (acetylacetonate) zirconium; metal alkoxides such as aluminum isopropoxide and titanium butoxide. Among these, from the viewpoint of curability and smoothness of the formed coating film, a phosphate ester-based curing catalyst (C1) is preferable. From the viewpoints of curability, smoothness of the formed coating film and water resistance, carbon is preferred. A monoalkyl phosphate having 1 to 8 carbon atoms, a dialkyl phosphate having 1 to 8 carbon atoms, or a mixture thereof is more preferable.
A hardening catalyst (C) may be used individually by 1 type, and may use 2 or more types together.

  As for content of a curing catalyst (C), 0.00001-10 mass% is preferable with respect to the total amount of solid content of the coating composition (a hardening | curing agent (B) is included) at the time of use. If the content of the curing catalyst (C) is 0.00001% by mass or more, the catalytic effect can be sufficiently obtained. When the content of the curing catalyst (C) is 10% by mass or less, the remaining curing catalyst (C) does not affect the coating film and the water resistance does not decrease.

[Organic solvent (D)]
The coating composition of the present invention may contain an organic solvent (D). As the organic solvent (D), conventionally used solvents such as toluene, xylene, methyl ethyl ketone, butyl acetate and the like can be used, but weak solvents are preferable from the viewpoint of reducing environmental burden.
The weak solvent is preferably a weak solvent species that can be used in the polymerization of the fluorinated polymer (A) or solvent substitution, and more preferably mineral spirits and mineral terpenes.
The content of the organic solvent (D) in the coating composition is appropriately determined in consideration of the solubility of the fluoropolymer (A), an appropriate viscosity when applied as a coating, a coating method, and the like.

[Pigment component (E)]
The coating composition of the present invention preferably contains a pigment component (E) for the purpose of rust prevention, coloring, reinforcement and the like.
The pigment component (E) is preferably one or more pigments selected from the group consisting of rust preventive pigments, colored pigments and extender pigments.
The rust preventive pigment is a pigment for preventing corrosion or alteration of the metal reflective substrate. Lead-free rust preventive pigments are preferred because of their low environmental impact. Examples of lead-free rust preventive pigments include cyanamide zinc, zinc oxide, zinc phosphate, calcium magnesium phosphate, zinc molybdate, barium borate, and calcium cyanamide zinc.
The color pigment is a pigment for coloring the coating film. Examples of the color pigment include titanium oxide, carbon black, and iron oxide. In the case of using a titanium oxide pigment, it is preferable that the pigment surface is treated for suppressing the photocatalytic action for the purpose of further improving the weather resistance of the coating film. D918 (product name, manufactured by Sakai Chemical Co., Ltd.) and PFC105 (product name, manufactured by Ishihara Sangyo Co., Ltd.) can be particularly recommended.
The extender pigment is a pigment for improving the hardness of the coating film and increasing the thickness. Examples of extender pigments include talc, barium sulfate, mica, and calcium carbonate.
As the pigment component (E), titanium oxide is particularly preferable from the viewpoint of excellent weather resistance.

  The content of the pigment component (E) in the coating composition of the present invention is based on the total solid content of the coating composition at the time of use (including the curing agent (B) when the curing agent (B) is used). 50-500 mass% is preferable, and 100-400 mass% is more preferable. When the content of the pigment component (E) is 50% by mass or more, the function of the pigment component (E) is easily obtained. When the content of the pigment component (E) is 500% by mass or less, the coating film is hardly cracked or damaged by impacts such as insect and bird collisions, and the weather resistance of the coating film is improved.

[Other resins (F)]
The coating composition of the present invention may contain a resin (F) other than the fluoropolymer (A).
Other resins (F) include acrylic resins, polyester resins, acrylic polyol resins, polyester polyol resins, urethane resins, acrylic modified silicone resins, silicone modified acrylic resins, silicone resins, alkyd resins, epoxy resins, oxetane resins, amino resins. Non-fluorinated resins such as The other resin (F) may be a resin that has a crosslinkable group and is cured by being crosslinked by the curing agent (B).
When mix | blending other resin (F) with the coating composition of this invention, as for content of other resin (F), 1-200 mass parts is preferable with respect to 100 mass parts of a fluoropolymer (A). .

[Other components (G)]
The coating composition of the present invention may contain other components (G) other than the components described above.
Other components (G) include a silane coupling agent for improving the adhesion of the coating film; a light stabilizer such as a hindered amine light stabilizer; a benzophenone compound, a benzotriazole compound, a triazine compound, and a cyanoacrylate compound. Organic ultraviolet absorbers such as compounds; inorganic ultraviolet absorbers such as titanium oxide, zinc oxide and cerium oxide; matting agents such as ultrafine powder synthetic silica; nonionic, cationic or anionic surfactants; Leveling agents; antistatic agents and the like.
Content of another component (G) can be suitably selected in the range which does not impair the effect of this invention.

Since the antistatic agent is blended in the coating composition of the present invention, a conductive coating film can be formed on the blade surface, and therefore, there is an effect of preventing the windmill blade from being damaged by lightning strike.
Specifically, a cation component such as Li ⁺ , Na ⁺ , K ⁺ , Cl ⁻ , Br ⁻ , I ⁻ , BF ₄ ⁻ , PF ₆ ⁻ , SCN ⁻ , ClO ₄ ⁻ , CF ₃ SO ₃ ⁻ , ( Alkali metal salts composed of anion components such as CF ₃ SO ₂ ) ₂ N ⁻ , (CF ₃ SO ₂ ) ₃ C ⁻ , antimony-doped tin dioxide, aluminum-doped zinc oxide, gallium-doped zinc oxide, gallium-doped indium oxide And metal oxides doped with non-oxide metals such as antimony-doped titanium oxide.

  If the coating composition of this invention demonstrated above is used, the coating film which has the outstanding weather resistance can be simply formed as a coating film which protects the braid | blade of a wind power generator. Further, the coating film has improved water repellency and can easily prevent the rotation of the blade from being hindered by snow adhesion. In addition, the decontamination property of the coating film is also improved.

[Wind generator blades]
Hereinafter, an example of an embodiment of a blade of a wind power generator according to the present invention will be described.
As shown in FIG. 1, the blade 1 of the wind power generator includes a blade base 11 and a coating film 12 formed on the blade base 11.

As the blade base 11, a blade base usually used in a wind power generator can be employed, and examples thereof include a blade base in which the surface of a wing-like plate piece made of wood is reinforced with fiber reinforced plastic (FRP).
The blade substrate is manufactured by a hand lay-up method using a polyester resin, a vacuum impregnation method using an epoxy resin, or the like.
The shape and size of the blade base 11 are not particularly limited.

The coating film 12 is a film formed for improving the weather resistance, snow-ice-ice property, and contamination removal property of the blade substrate 11, and is formed by the above-described coating composition of the present invention.
As for the thickness of the coating film 12, 50-150 micrometers is preferable.

  Another layer may exist between the blade substrate 11 and the coating film 12. Examples of the other layer include a resin layer made of an alkyd resin, an epoxy resin, and an acrylic resin, and a layer made of a silane coupling agent for improving the adhesion of the coating film.

[Production method]
As an example of the method for producing the blade of the wind power generator of the present invention, a method for producing the blade 1 using the coating composition containing the fluoropolymer (A) and the curing agent (B) described above will be described.
As a manufacturing method of the blade 1, for example, a coating composition containing at least a fluoropolymer (A) is applied to the surface of the blade base 11 to form an application layer, and then cured to form a coating film comprising a cured coating film. The method of forming the film | membrane 12 is mentioned.

The coating composition can be applied using a brush, roller, spray, flow coater, applicator or the like. What is necessary is just to select the application quantity of a coating composition suitably so that a dry film thickness may become in the said range. The temperature for thermosetting the coating composition is preferably from room temperature to 250 ° C.
When the coating composition contains a solvent, the solvent is preferably removed by volatilization by heating, decompression or the like before or after curing.

  According to the coating composition of the present invention, the weather resistance, snow-sliding ice property, and decontamination property of the blade of the wind power generator are improved.

Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples. However, the present invention is not limited by the following description.
<Production of fluoropolymer (A)>
[Example 1]
To an autoclave with a stainless steel stirrer with an internal volume of 3000 mL, 722 g of xylene, 189 g of ethanol, 90.7 g of HBVE which is a monomer having a hydroxyl group, 284.5 g of CHVE which is another monomer, and 2-ethyl 202.9 g of xyl vinyl ether (EHVE) and 9.5 g of potassium carbonate were added all at once, and dissolved oxygen was removed by nitrogen.
Next, 505 g of CTFE, a fluoroolefin, was introduced into the autoclave and the temperature was gradually raised. After reaching 65 ° C., 7 g of a 50% xylene solution of t-butyl peroxypivalate was added over 7 hours. The reaction was stopped after introduction into an autoclave and further stirring for 15 hours. Thereafter, potassium carbonate was removed by filtration to obtain a xylene solution of a hydroxyl group-containing fluoropolymer (nonvolatile content 60%, hydroxyl value 36 mgKOH / g).
To a 1 L eggplant-shaped flask, 600 g of the xylene solution of the hydroxyl group-containing fluoropolymer and 210 g of mineral spirit were added, and the solvent was replaced with mineral spirit while evaporating. Mineral spirit of the hydroxyl group-containing fluoropolymer A solution (73.5% non-volatile content) was obtained.

In a 500 mL four-necked flask equipped with a thermometer, a reflux condenser, and a stirrer, 326.5 g of the mineral spirit solution of the hydroxyl group-containing fluoropolymer and 3-isocyanatopropyltriethoxy which is the compound (1a) 38.1 g of silane (IPTES) and 0.05 g of tin 2-ethylhexylate were added and reacted at 50 ° C. for 5 hours in a nitrogen atmosphere.
When the composition of the obtained polymer was measured by ¹ H-NMR (proton NMR), the unit of CTFE / the unit based on CHVE / the unit based on EHVE / the unit based on HBVE / the hydroxyl group of the unit based on HBVE and IPTES The unit (mol%) with which the isocyanate group reacted was 50/26/15/1/8.
After the reaction, trimethyl orthoformate (13.6 g) and isopropanol (13.6 g) were added, respectively, and a mineral spirit solution of the alkoxysilyl group-containing fluoropolymer (fluoropolymer (A)) (nonvolatile content: 70.0%) )

<Manufacture of coating composition>
[Example 2]
To 214 g of the mineral spirit solution (non-volatile content 70%) of the fluoropolymer (A) obtained in Example 1, titanium oxide as a pigment component (E) (trade name “D-918” manufactured by Sakai Chemical Co., Ltd.) 250 g of mineral spirits and 100 g of mineral spirits were added, and 369 g of glass beads having a diameter of 1 mm were further added, followed by stirring for 2 hours with a paint shaker. After stirring, filtration was performed to remove the glass beads to obtain a pigment composition.
Next, the pigment composition is 126 g of a mineral spirit solution (nonvolatile content: 70%) of the fluoropolymer (A), 119 g of phenyltrimethoxysilane as a curing agent (B), and a curing catalyst (C). 2 g of phosphoric acid catalyst (trade name “AP-8”, manufactured by Daihachi Chemical Industry Co., Ltd.), hydroxyl group-containing silicone-modified acrylic resin (BYK-Chemie, product name “BYK-Silclean 3700”) as another resin (F) ) And 1 g of a leveling agent (trade name “BYK-300”, manufactured by BYK-Chemie) were further added and mixed to obtain a coating composition.

[Example 3]
To 83 g of Lumiflon LF200 (product name, xylene solution of a hydroxyl group-containing fluoropolymer produced by AGC Asahi Glass Co., Ltd., non-volatile content 60%), titanium oxide (manufactured by Sakai Chemical Co., Ltd., trade name “ 200 g of D-918 "), 43 g of xylene and 43 g of butyl acetate were added, and 369 g of glass beads having a diameter of 1 mm were further added, followed by stirring for 2 hours in a paint shaker. After stirring, filtration was performed to remove the glass beads to obtain a pigment composition.
Next, 100 g of the pigment composition, 150 g of Lumiflon LF200, 18.5 g of an HDI nurate type polyisocyanate resin (trade name “Coronate HX” manufactured by Nippon Polyurethane Co., Ltd.) as a curing agent, and a curing catalyst Dibutyltin dilaurate (diluted 4 to 10 times with xylene to 3 g) was further added and mixed to obtain a coating composition.

<Evaluation of coating film formed by coating composition>
[Example 4]
The coating composition obtained in Example 2 was applied to the surface of a glass epoxy substrate impregnated with glass cloth with an epoxy resin so as to have a film thickness of 50 μm, and was cured in a constant temperature room at 25 ° C. for 1 week. It was. Then, the test board with a coating film (I-1) was created by making it dry in 80 degreeC oven for 1 hour. About the test plate with a coating film (I-1) thus obtained, “mirror glossiness of the coating film”, “adhesion to the ground”, “contact angle of the coating film”, “carbon contamination of the coating film”, The “snow sliding ice property of the coating film” was evaluated by the following test method. Moreover, except having changed the board | substrate into the aluminum plate, the test plate with a coating film (I-2) was created by the same method, and "the weather resistance of a coating film" was evaluated with the following test method.

[Example 5]
The coating composition obtained in Example 3 was applied to the surface of a glass epoxy substrate impregnated with glass cloth with an epoxy resin so as to have a film thickness of 50 μm, and was cured in a constant temperature room at 25 ° C. for 1 week. It was. Then, the test board (II-1) with a coating film was created by making it dry in 80 degreeC oven for 1 hour. With respect to the test plate with a coating film (II-1) thus obtained, “specular gloss of coating layer”, “hardness of coating layer”, “adhesion to substrate”, “contact angle of coating layer”, “coating” “Carbon contamination of film” and “sliding ice property of coating film” were evaluated by the following test methods. Moreover, except having changed the board | substrate into the aluminum plate, the test plate with a coating film (II-2) was created by the same method, and "the weather resistance of a coating film" was evaluated with the following test method.

[Test method]
1. Mirror gloss of the coating film Measured according to JIS Z 5400-7-6.
2. Hardness of coating film Measured according to JIS K 5600-5-4.
3. Adhesion to the substrate Measured according to JIS Z 5600-5-6.
4). Contact angle of the coating film FACE contact angle meter CA-A type (manufactured by Kyowa Interface Chemical Co., Ltd.) was used to adjust the ion exchange water to 0.005 ml, and the contact angle of each test plate was measured.

5. Carbon stain resistance of coating film Dropper of carbon suspension water (dispersed dispersion for 2 hours in paint shaker with glass beads added to 5 parts of carbon black Color Black FW200 manufactured by Degussa Huls) and 95 parts of deionized water Was added dropwise until the test plate with the coating film was concealed, and immediately dried at 50 ° C. for 1 hour. After drying, the sample was allowed to cool to room temperature, and the surface of the test piece was washed with running gauze under running water until the soiled material did not fall off. After washing, it was dried at room temperature for 3 hours, and the degree of soiling was measured with a color difference meter to determine the lightness difference (ΔL *) of the coating film before and after the test and evaluated in the following three stages. In addition, it shows that it is a coating material excellent in stain resistance, so that a brightness difference is small.
Lightness difference (ΔL *) = [Coating film brightness after test (L * 1) −Coating film brightness before test (L * 0)]
“◯”: The brightness difference was −5 or more.
“Δ”: The brightness difference was −10 or more and less than −5.
"X": The brightness difference was less than -10.

6). Snow-sliding ice property of coating film A test plate with a coating film was placed in a freezer at -20 ° C and left overnight.
A total of nine pieces of 50 μL of ion-exchanged water were placed on the test plate with a coating film with a dropper so that one drop of each water drop.
Furthermore, the water droplets were frozen by being left overnight and kept at -20 ° C.
The evaluation of snow sliding ice property was carried out according to the following criteria.
“◯”: Ice was dropped by simply tapping the test plate with a hand while keeping the test plate with the coating film horizontal.
"△": It fell by touching with ice with a hand.
“X”: Ice could not be removed, or the ice was broken and a part of the ice remained on the surface.

7). The weather resistance of the coating film A test plate with a coating film whose substrate is an aluminum plate was installed outdoors in Naha City, Okinawa Prefecture. The gloss of the coating film surface immediately before installation and two years later was measured using PG-1M (gloss meter: Nippon Denshoku Industries Co., Ltd.). When the gloss value immediately before installation was 100%, the ratio of the gloss value after 2 years was calculated as the gloss retention (unit:%), and the weather resistance was evaluated according to the following criteria.
“◯”: The gloss retention was 80% or more.
“Δ”: The gloss retention was 60% or more and less than 80%.
"X": The gloss retention was less than 60%.
The evaluation results are shown in Table 1.

  As shown in Table 1, the coated test plate of Example 4 having a coating film formed from the coating composition of the present invention is compared with the coated test plate of Example 5 having a conventional coating film. , High hardness and water contact angle, excellent resistance to contamination and snow ice.

  DESCRIPTION OF SYMBOLS 1 Wind generator blade 11 Blade base body 12 Coating film

Claims (8)

  A coating composition for coating a surface of a blade of a wind power generator, comprising a fluorine-containing polymer (A) having a hydrolyzable silyl group as an essential component.   The fluorine-containing polymer having the hydrolyzable silyl group is a fluorine-containing polymer having a repeating unit (A1) based on a fluoroolefin and a repeating unit (A2) having a hydrolyzable silyl group. A coating composition for wind turbine blade surface coating. The blade of the wind power generator according to claim 1 or 2, wherein the repeating unit (A2) having the hydrolyzable silyl group is a repeating unit (A2-1) having a group represented by the following formula (1). A coating composition for surface coating.
—OC (O) NH (CH ₂ ) _m SiX ¹ _n R ¹ _3-n (1)
(Wherein R ¹ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms, X ¹ is an alkoxy group having 1 to 5 carbon atoms, n is an integer of 1 to 3, and m is an integer of 1 to 5) Show.)   The wind power according to any one of claims 1 to 3, wherein the fluoroolefin is at least one selected from the group consisting of tetrafluoroethylene, chlorotrifluoroethylene, hexafluoropropylene, vinylidene fluoride, and vinyl fluoride. A coating composition for surface coating of generator blades. The fluorine paint containing the fluoropolymer (A) containing a hydrolyzable silyl group as an essential component contains the following curing agent (B), phosphate ester-based curing catalyst (C1), and organic solvent (D). The coating composition for surface application | coating of the blade of the wind power generator as described in any one of Claims 1-4 characterized by these.
Curing agent (B): a compound represented by the following formula (2) and / or a partial hydrolysis-condensation product thereof.
SiX ² _a R ² _4-a (2)
(Wherein R ² represents a monovalent hydrocarbon group having 1 to 10 carbon atoms, X ² represents an alkoxy group having 1 to 10 carbon atoms, and a represents an integer of 2 to 4)   Furthermore, the coating composition for surface application | coating of the blade of the wind power generator as described in any one of Claims 1-5 formed by containing a titanium oxide.   A method for producing a blade of a wind power generator, wherein the coating composition for coating the surface of the blade of the wind power generator according to any one of claims 1 to 6 is applied to the surface of the blade base to form a coating layer and cured. .   The blade of a wind power generator which has the coating film formed from the coating composition for surface coating of the blade of the wind power generator blade as described in any one of Claims 1-6 on the blade base | substrate surface.

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