WO2010101146A1

WO2010101146A1 - Coating agent composition

Info

Publication number: WO2010101146A1
Application number: PCT/JP2010/053336
Authority: WO
Inventors: 俊齋藤; 祥増田
Original assignee: 旭硝子株式会社
Priority date: 2009-03-02
Filing date: 2010-03-02
Publication date: 2010-09-10
Also published as: JPWO2010101146A1

Abstract

Provided is a fluorine-containing coating agent composition which provides a highly weatherproof film having excellent scribble removing properties, dirt removing properties, and ink repellency. A fluorine-containing coating agent comprising (A) a fluorine-containing polymer having a hydrolyzable silyl group, (B) a curing agent, (C) a phosphate ester-based catalyst, (D) an organic solvent, and (E) a non-fluoropolymer having an organosiloxane group provides a highly weatherproof film having excellent scribble removing properties, dirt removing properties, and ink repellency by curing the agent.

Description

Coating agent composition

The present invention relates to a coating agent composition used for forming a coating film on the surface of a substrate, more specifically, a fluorine-containing coating agent that provides a highly weather-resistant coating film excellent in graffiti removal, decontamination, and ink repellency. The present invention relates to a composition, a method for producing a cured coating film formed from the coating agent composition, and a coated article having the cured coating film.

Fluorine-containing coating compositions such as paints, hard coats, and substrate protective coatings are excellent in weather resistance and UV resistance, so they can be used as maintenance-free high-performance coatings for high-rise buildings, large structures, ships, etc. , Used in a wide range of vehicles, residential properties, bridges, etc.

In recent years, the decline in aesthetics due to graffiti on various outdoor walls such as exterior walls of various buildings, pedestrian bridges, bridges, block fences, store shutters and telephone boxes has become a major social problem.
A felt pen used for graffiti is generally composed mainly of ink in which a dye or a pigment is dispersed in an organic solvent or water. Since the ink easily penetrates into fine irregularities in the coating film, once the ink adheres to the coating film, it is difficult to completely remove the ink, and it is difficult to return to the original state. There was no other way than repainting and erasing.
Conventionally, as a means for easily removing graffiti, methods of Patent Documents 1 and 2 below in which graffiti-removable fluorine paint is applied to a wall surface or the like have been proposed.

On the other hand, in recent years, fluororesin paints have been switched to weak solvent-type fluororesin paints, which are environmentally friendly paints, due to the impact on the base (old paint film) during repairs and the burden on the global environment. Yes. The fluororesin used in the weak solvent type fluororesin coating has a low hydroxyl value in the resin due to the problem of solubility in the weak solvent. As a result, the coating film formed from the fluororesin coating has a problem that the crosslinking density is low and the coating film surface hardness is low. Therefore, even if the coating film is formed from a fluororesin coating material in which an antifouling component is blended in the coating material, if the ink adheres to the coating film by graffiti or the like, the ink is easily added to the coating film. Invading and its removal was not easy.

JP 2008-127424 A WO2004 / 0676758 pamphlet

Patent Document 1 discloses a fluororesin coating composition in which a silicone-modified acrylic resin having a hydroxyl group at a terminal and a matting agent are blended with a fluororesin. However, the coating composition has a low surface gloss of the coating film due to the effect of the matting agent, and is unsuitable for applications requiring high coating gloss. In addition, the surface of the coating film was rough due to the effect of the matting agent, and it was not easy to remove the ink component adhering to the coating film surface.
Patent Document 2 discloses a fluororesin coating composition in which a liquid polydialkylsiloxane containing an amino group and a curing agent are blended with a fluororesin. However, the coating film formed from the coating composition has a problem that the surface hardness may be insufficient, and the coating film is damaged by a brush or the like used for wiping off the dirt component.

An object of the present invention is to provide a fluorine-containing coating agent composition that provides a highly weather-resistant coating film excellent in graffiti removal, contamination removal, and ink repellency.

The inventors have prepared a fluorine-containing polymer (A) containing a hydrolyzable silyl group, a curing agent (B), a phosphate ester catalyst (C), an organic solvent (D), and a non-fluorine having an organosiloxane group. The fluorine-containing coating agent containing the polymer (E) was found to give a highly weather-resistant coating film excellent in graffiti removal, contamination removal, and ink repellency after curing, and the present invention was completed. .

That is, the present invention includes the following [1] to [12].
[1] Curing agent (B) comprising the following fluoropolymer (A), a compound represented by the following formula (2) and / or a partially hydrolyzed condensate thereof, phosphate ester curing catalyst (C), organic A coating agent composition comprising a solvent (D) and a non-fluorine polymer (E) having an organosiloxane chain.
Fluoropolymer (A): A fluoropolymer comprising a repeating unit (A1) based on a fluoroolefin and a repeating unit (A2) having a group represented by the following formula (1).
—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.)
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 1 to 4)
[2] The repeating unit (A2) polymerizes a repeating unit based on a monomer comprising a reaction product of a hydroxyl group of the hydroxyl group-containing monomer and an isocyanate group of the compound represented by the following formula (1a), or a hydroxyl group-containing monomer. The coating agent composition according to the above [1], which is a repeating unit obtained by reacting the isocyanate group of the compound represented by the following formula (1a) with the hydroxyl group of the repeating unit.
OCN (CH ₂ ) _m SiX ¹ _n R ¹ _3-n (1a)
(In the formula, R ¹ , X ¹ , n, and m are as described above.)
[3] With respect to 100 parts by mass of the fluoropolymer (A), 10 to 200 parts by mass of the curing agent (B) represented by the formula (2) and 0 of the phosphoric ester-based curing catalyst (C) [1] or [2], containing 0.01 to 10 parts by mass, 10 to 150 parts by mass of the organic solvent (D), and 0.01 to 10 parts by mass of the non-fluorinated polymer (E) having an organosiloxane chain The coating agent composition described in 1. Coating composition.
[4] A repeating unit based on a monomer in which the fluoropolymer (A) is composed of a repeating unit (A1) and a repeating unit (A2) together with an alkyl group and a polymerizable unsaturated group connected by an ether bond or an ester bond. The coating agent composition according to any one of [1] to [3] above, which is a polymer comprising (A3) and / or a repeating unit (A4) based on a hydroxyl group-containing monomer.
[5] The ratio of the repeating unit (A1) to the total content of the repeating unit (A1) and the repeating unit (A2) in the fluoropolymer (A) is 10 to 99 mol%, and the repeating unit (A2) The ratio of the total of the repeating units (A1) and the repeating units (A2) is 1 to 90 mol% and the total content of all the repeating units in the fluoropolymer (A) is The coating agent composition according to the above [4], which is 30 to 100 mol%, the proportion of the repeating unit (A3) is 70 to 0 mol%, and the proportion of the repeating unit (A4) is 30 to 0 mol%. object.
[6] The coating composition according to any one of [1] to [5], wherein the phosphate ester curing catalyst (C) is an acidic phosphate ester compound having an acid value of 10 to 800 mgKOH / g.
[7] The coating agent composition according to any one of the above [1] to [6], wherein the organic solvent (D) is a weak solvent.
[8] The coating agent composition according to any one of [1] to [7] above, wherein the non-fluorinated polymer (E) having an organosiloxane chain has a hydroxyl value of 30 to 200 mgKOH / g.
[9] The non-fluorine polymer (E) having an organosiloxane chain is at least one selected from the group consisting of a silicone resin, a silicone-modified epoxy resin, a silicone-modified phenol resin, a silicone-modified acrylic resin, and a silicone-modified polyester resin. The coating agent composition according to any one of [1] to [8] above.
[10] The coating agent composition according to any one of the above [1] to [9], comprising titanium oxide.
[11] A method for producing a cured coating film, wherein the coating agent composition according to any one of [1] to [10] is applied to an article surface and cured.
[12] A coated article having a cured coating film formed from the coating composition according to any one of [1] to [10] on the article surface.

According to the present invention, there is provided a coating agent composition that provides a highly weather-resistant coating film excellent in graffiti removal, contamination removal, and ink repellency.

In this specification, the repeating unit obtained directly by polymerization and the repeating unit obtained by reacting the repeating unit obtained by polymerization with another compound are collectively referred to as “unit”. Further, the compound represented by the formula (1a) is referred to as the compound (1a), the group represented by the formula (1) is referred to as the group (1), and the unit (A1) based on the fluoroolefin is simply referred to as the unit (A1). Sometimes. Other units may be similarly described.

The coating agent composition of the present invention comprises a fluorine-containing polymer (A), a curing agent (B), a phosphate ester curing agent (C), an organic solvent (D), and a non-fluorine polymer having an organosiloxane chain ( E).

[Fluoropolymer (A)]
The fluorine-containing polymer (A) is a fluorine-containing polymer containing a unit (A2) having a unit (A1) of a fluoroolefin and a group (1). The fluoropolymer (A) is a unit of a monomer in which an alkyl group and a polymerizable unsaturated group are linked by an ether bond or an ester bond (hereinafter referred to as “alkyl group-containing monomer”) as an optional component. (A3), a hydroxyl group-containing monomer unit (A4), and other units may be included.

[Unit (A1)]
The unit (A1) is a fluoroolefin unit. A fluoroolefin is a compound in which one or more hydrogen atoms of an unsaturated hydrocarbon compound are substituted with fluorine atoms, and a part or all of the remaining hydrogen atoms may be substituted with chlorine atoms. It is a sex compound.
Of the hydrogen atoms of the unsaturated hydrocarbon compound, the number of hydrogen atoms substituted with fluorine atoms (hereinafter referred to as “fluorine addition number”) is preferably 2 or more, and more preferably 3 to 4. When the fluorine addition number is 2 or more, the weather resistance of the coating film is sufficient.

The fluoroolefin is preferably a fluoroolefin having 2 to 3 carbon atoms such as tetrafluoroethylene, chlorotrifluoroethylene, hexafluoropropylene, vinylidene fluoride, vinyl fluoride, etc., from the viewpoint of the weather resistance and solvent resistance of the coating film. Tetrafluoroethylene and chlorotrifluoroethylene (hereinafter referred to as “CTFE”) are more preferable.
The unit (A1) may be only one type or a combination of two or more types.

[Unit (A2) having group (1)]
The unit (A2) is a unit having a group (1). In the group (1), X ¹ is an alkoxy group having 1 to 5 carbon atoms, preferably an ethoxy group or a methoxy group. Within this range the number of carbon atoms in X ^1, the alcohol component generated by a condensation reaction is less likely to remain in the coating film after curing, water resistance of the coating film, the solvent resistance is improved.

R ¹ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms, preferably a monovalent hydrocarbon group.
The monovalent hydrocarbon group preferably has 1 to 5 carbon atoms, more preferably 1 or 2. Specifically, a methyl group or an ethyl group is preferable. When the carbon number of the monovalent hydrocarbon group is within this range, the group (1) does not become too bulky, and the condensation reaction of the alkoxy group (X ¹ ) proceeds smoothly when the coating film is cured. When the condensation reaction of the alkoxy group (X ¹ ) is sufficiently advanced, the coating film is sufficiently cured, the surface hardness of the coating film is sufficiently high, and the graffiti removal property, stain resistance, and weather resistance are good. Become.
n is an integer of 1 to 3, preferably 2 or 3, and more preferably 3.
m is an integer of 1 to 5, preferably 2 to 5, and more preferably 2 to 4.

The group (1) includes a urethane-bonded nitrogen atom having the formula: — (CH ₂ ) ₃ Si (OCH ₃ ) ₃ , — (CH ₂ ) ₃ Si (OC ₂ H ₅ ) ₃ , — (CH ₂ ) ₃ Si (CH ₃ ) (OCH ₃ ) ₂ , — (CH ₂ ) ₃ Si (CH ₃ ) (OC ₂ H ₅ ) ₂ , — (CH ₂ ) ₃ Si (CH ₃ ) ₂ (OCH ₃ ), — (CH ₂ ) ₃ Si (CH ₃ ) ₂ (OC ₂ H ₅ ), — (CH ₂ ) ₄ Si (OCH ₃ ) ₃ , — (CH ₂ ) ₄ Si (OC ₂ H ₅ ) ₃ , — (CH ₂ ) ₂ A group in which groups represented by Si (OCH ₃ ) ₃ and — (CH ₂ ) ₂ Si (OC ₂ H ₅ ) ₃ are bonded is preferable.
Among these groups, since raw materials are easy to obtain, the formula: — (CH ₂ ) ₃ Si (OCH ₃ ) ₃ , — (CH ₂ ) ₃ Si (OC ₂ H ₅ ) is attached to the nitrogen atom of the urethane bond. A group to which a group represented by ₃ is bonded is more preferred.

The unit (A2) is a unit obtained by polymerizing a monomer comprising a reaction product of a hydroxyl group of a hydroxyl group-containing monomer and an isocyanate group of the compound (1a) represented by the following formula, or a unit obtained by polymerizing a hydroxyl group-containing monomer. It is preferably any unit obtained by reacting the isocyanate group of the compound (1a) with a hydroxyl group. In any case, the structure of the unit (A2) is determined by the type of the hydroxyl group-containing monomer and the compound (1a) to be combined.

OCN (CH ₂ ) _m SiX ¹ _n R ¹ _3-n (1a)
(Wherein R ¹ , X ¹ , n and m have the same meaning as described above).

Examples of the hydroxyl group-containing monomer include hydroxyalkyl vinyl ethers such as 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, 1,4-cyclohexane dimethanol monovinyl ether; diethylene glycol monovinyl ether, triethylene glycol monovinyl ether, tetraethylene glycol Polyethylene glycol monovinyl ethers such as monovinyl ether; Hydroxyalkyl allyl ethers such as 2-hydroxyethyl allyl ether, 4-hydroxybutyl allyl ether, 1,4-cyclohexanedimethanol monoallyl ether; Diethylene glycol monoallyl ether, tri Polyethylene such as ethylene glycol monoallyl ether and tetraethylene glycol monoallyl ether Lenglycol monoallyl ethers; hydroxyalkyl vinyl esters such as hydroxyacetic acid vinyl ester, 3-hydroxypropionic acid vinyl ester, 4-hydroxybutyric acid vinyl ester; hydroxyacetic acid allyl ester, 3-hydroxypropionic acid allyl ester, 4 -Hydroxyalkylcarboxylic acid allyl esters such as hydroxybutyric acid allyl ester; (meth) acrylic acid hydroxymethyl ester, (meth) acrylic acid 2-hydroxyethyl ester, (meth) acrylic acid 3-hydroxypropyl ester, (meth) acrylic (Meth) acrylic acid hydroxyalkyl esters such as acid 1,4-cyclohexanedimethanol monoester; vinyl acetate hydroxymethyl ester, vinyl acetate 2-hydroxy ester Glycol ester, vinyl acetate 3-hydroxypropyl esters, vinyl acetate hydroxyalkyl esters such as vinyl acetate 1,4-cyclohexanedimethanol mono-esters are preferred. However, (meth) acrylic acid shows either acrylic acid or methacrylic acid.
When the hydroxyl group-containing monomer is polyethylene glycol monovinyl ethers or polyethylene glycol monoallyl ethers, the number of polyethylene glycol moieties to be polymerized is preferably 2-20, more preferably 2-15, and even more preferably 2-10.

As the hydroxyl group-containing monomer, hydroxyalkyl vinyl ethers and polyethylene glycol monovinyl ethers are more preferable because of excellent alternating copolymerization and good weather resistance of the formed coating film. Specifically, hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, and diethylene glycol monovinyl ether are more preferable.
Only one type of hydroxyl group-containing monomer may be used, or two or more types may be used in combination.

In the compound (1a), preferred types of groups represented by R ¹ and X ¹ and preferred ranges of values of n and m are the same as those in the case of the group (1).
That is, in the compound (1a), R ¹ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, and more preferably 1 or 2. Specifically, a methyl group or an ethyl group is preferable. X ¹ is an alkoxy group having 1 to 5 carbon atoms, preferably an ethoxy group or a methoxy group. n is an integer of 1 to 3, preferably 3, m is an integer of 1 to 5, and 2 to 4 is more preferable.

Examples of the compound (1a) include 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-isocyanatopropylmethyldimethoxysilane, 3-isocyanatepropylmethyldiethoxysilane, 3-isocyanatepropyldimethylmethoxysilane, 3- Isocyanatepropyldimethylethoxysilane, 4-isocyanatobutyltrimethoxysilane, 4-isocyanatobutyltriethoxysilane, 2-isocyanatoethyltrimethoxysilane, and 2-isocyanatoethyltriethoxysilane are preferred.
Since the compound (1a) is easily available, 3-isocyanatopropyltrimethoxysilane and 3-isocyanatopropyltriethoxysilane are more preferable.
Only 1 type may be used for a compound (1a) and it may use it in combination of 2 or more type.

The method for obtaining the unit (A2) is preferably any one of the following method (i) and method (ii).
<Method (i)>
Step (i-1): The reaction product is obtained by reacting the hydroxyl group of the hydroxyl group-containing monomer with the isocyanate group of the compound (1a).
Step (i-2): The monomer that is the reaction product of step (i-1) is copolymerized with the fluoroolefin and, if necessary, other monomers.

<Method (ii)>
Step (ii-1): A copolymer having a hydroxyl group in the side chain is obtained by copolymerizing a hydroxyl group-containing monomer, a fluoroolefin, and another monomer as required.
Step (ii-2): The isocyanate group of compound (1a) is reacted with the hydroxyl group of the side chain of the copolymer obtained in step (ii-1).

When the method (i) is employed, the unit (A2) is a polymerized unit obtained by polymerizing a monomer composed of a reaction product of a hydroxyl group-containing monomer and the compound (1a).
Specific examples of the monomer include a reaction product of 2-hydroxyethyl vinyl ether and 3-isocyanatopropyltrimethoxysilane, a reaction product of 2-hydroxyethyl vinyl ether and 3-isocyanatepropyltriethoxysilane, and 4-hydroxybutyl. Reaction product of vinyl ether and 3-isocyanatopropyltrimethoxysilane, reaction product of 4-hydroxybutyl vinyl ether and 3-isocyanatepropyltriethoxysilane, reaction product of diethylene glycol monovinyl ether and 3-isocyanatepropyltrimethoxysilane A reaction product of diethylene glycol monovinyl ether and 3-isocyanatopropyltriethoxysilane is preferred.

Among these, 2-hydroxyethyl vinyl ether and 3-isocyanatopropyl trimethyl are preferred because of the ease of monomer purification, the stability of the fluoropolymer (A), the compatibility with the curing agent component, and the good reactivity. A reaction product of ethoxysilane, a reaction product of 4-hydroxybutyl vinyl ether and 3-isocyanatopropyltriethoxysilane, and a reactive organism of diethylene glycol monovinyl ether and 3-isocyanatopropyltriethoxysilane are more preferable.
The monomer used at the time of polymerization may be used alone or in combination of two or more.

When the method (ii) is employed, the unit (A2) is a unit in which the compound represented by the formula (1a) is reacted with the polymerization unit of the hydroxyl group-containing monomer.
Specific examples of the unit include a unit obtained by reacting a unit of 2-hydroxyethyl vinyl ether and 3-isocyanatopropyltrimethoxysilane, and a unit of 2-hydroxyethyl vinyl ether and 3-isocyanatepropyltriethoxysilane. A unit obtained by reacting 4-hydroxybutyl vinyl ether unit with 3-isocyanatopropyltrimethoxysilane, a unit obtained by reacting 4-hydroxybutyl vinyl ether unit with 3-isocyanatopropyltriethoxysilane, diethylene glycol monovinyl ether Units obtained by reacting units with 3-isocyanatopropyltrimethoxysilane, units obtained by reacting units of diethylene glycol monovinyl ether and 3-isocyanatepropyltriethoxysilane Preferred.

Among these, the stability of the fluoropolymer (A), the compatibility with the curing agent component, and the reactivity are good, so the unit of 2-hydroxyethyl vinyl ether reacts with 3-isocyanatopropyltriethoxysilane. More preferred are units obtained by reacting 4-hydroxybutyl vinyl ether units with 3-isocyanatopropyltriethoxysilane, and units obtained by reacting diethylene glycol monovinyl ether units with 3-isocyanatopropyltriethoxysilane.

That is, in both methods (i) and (ii), the unit (A2) is a combination of 2-hydroxyethyl vinyl ether and 3-isocyanatopropyltriethoxysilane, 4-hydroxybutyl vinyl ether and 3-isocyanate. A structure obtained by a combination with propyltriethoxysilane or a combination of diethylene glycol monovinyl ether and 3-isocyanatepropyltriethoxysilane is more preferable.
Only one type of unit (A2) may be used, or a combination of two or more types may be used.

In the present invention, how to obtain the unit (A2) may be appropriately selected in view of ease of production, cost, etc., and the method (i) is carried out under polymerization conditions in order to prevent gelation during production. However, it is more preferable to obtain the unit (A2) by the method (ii) because the method (ii) is easy to produce compared to the need to strictly control and manage the process.

The addition reaction between the hydroxyl group-containing monomer and the compound (1a) in the step (i-1) and the addition reaction between the hydroxyl group-containing copolymer and the compound (1a) in the step (ii-2) In a solvent containing no active hydrogen that reacts with the group (for example, ethyl acetate, methyl ethyl ketone, xylene, etc.), 0.1 to 10 moles, preferably 0.5 to 5 moles of compound (1a) per mole of hydroxyl group It is preferable to react at a molar ratio.
When the amount of the compound (1a) is more than 0.1 mol, a sufficient curing reaction occurs and the original performance of the coating film such as weather resistance, solvent resistance and impact resistance can be sufficiently exhibited. When the amount of the compound (1a) is less than 10 mol, the compound hardly remains in the coating film in a large amount as an unreacted product, and the water resistance and solvent resistance of the coating film are improved.

In step (i-1), the reaction between the hydroxyl group and the isocyanate group can be carried out with a yield of almost 100%. However, in order to increase the yield, if a catalyst is added or the reaction temperature is increased, the reaction product may be gelled. Therefore, the reaction may be performed under conditions where the conversion rate is lower than 100%. preferable. For example, the step (i-2) may be performed after removing the unreacted hydroxyl group-containing monomer from the reaction product, or the step (i-2) is performed while the reaction product still contains the unreacted hydroxyl group monomer. May be. However, it is preferable that the amount of the unreacted hydroxyl group-containing monomer is small, and the water resistance of the coating is improved by reducing the hydroxyl group content of the fluoropolymer (A) obtained in the step (i-2).

In step (ii-2), it is preferable that 50 mol% or more of the hydroxyl groups contained in the fluoropolymer (A) are modified by reacting with the isocyanate groups of the compound (1a). When it is 50% or more, the water resistance of the paint is improved. Although it is possible to modify 100% of the hydroxyl groups, the higher the amount of the compound (1a) used, the higher the cost. Therefore, a modification rate of 50 to 70% is preferable from the viewpoint of reducing the cost.

When step (i-2) is carried out while containing unreacted hydroxyl monomer in step (i-1) of method (i), and in step (ii-2) of method (ii) 100 When less than mol% is modified by reacting with the isocyanate group of the compound (1a), the obtained fluoropolymer (A) becomes a polymer containing units based on a hydroxyl group-containing monomer.

In step (i-1) and step (ii-2), the addition reaction between a hydroxyl group and an isocyanate group is usually performed at room temperature to 100 ° C., preferably 50 to 70 ° C., under an inert atmosphere such as nitrogen. Is preferred. The reaction time can be appropriately changed according to the progress of the reaction, preferably 1 to 24 hours, particularly preferably 3 to 10 hours. In the addition reaction system, an organometallic catalyst such as an organotin compound, an organoaluminum compound, an organozirconium compound, or an organotitanate compound is preferably present for the purpose of promoting the reaction.

[Contents of Unit (A1) and Unit (A2) in Fluoropolymer (A))
The proportion of the unit (A1) in the fluoropolymer (A) is preferably from 10 to 99 mol%, more preferably from 30 to 95 mol%, based on the total content of the unit (A1) and the unit (A2). . When the proportion of the unit (A1) is less than 10 mol%, the weather resistance of the coating film is lowered, and when it exceeds 99 mol%, the adhesion with the substrate is lowered, which is not preferable.

The proportion of the unit (A2) in the fluoropolymer (A) is preferably from 1 to 90 mol%, more preferably from 5 to 70 mol%, based on the total content of the unit (A1) and the unit (A2). . When the unit (A2) is 1 mol% or more, the degree of cure of the coating film is sufficiently high, and the weather resistance is also good. Moreover, when it is 90 mol% or less, the stability of the fluoropolymer (A) is improved, and the pot life of the coating is also sufficient.
Further, the total ratio of the unit (A1) and the unit (A2) with respect to all the units in the fluoropolymer (A) is preferably from 30 to 100 mol%, more preferably from 50 to 100 mol%. Furthermore, the ratio of the unit (A1) to the total units in the fluoropolymer (A) is preferably 10 to 90 mol%, more preferably 30 to 70 mol%.

Fluoropolymer (A) in the present invention may optionally contain units other than units (A1) and units (A2). As units other than the unit (A1) and the unit (A2), a unit (A3) based on an alkyl group-containing monomer and / or a unit (A4) based on a hydroxyl group-containing monomer are preferable. Moreover, the other unit may be included as needed.

[Units based on alkyl group-containing monomer (A3)]
In the unit (A3) based on the alkyl group-containing monomer, the alkyl group-containing monomer has an alkyl group and a polymerizable unsaturated group linked by an ether bond or an ester bond (hereinafter referred to as “linked bond” by combining the ether bond and the ester bond). It is preferably a unit obtained by polymerizing the monomer.

The polymerizable unsaturated group is preferably an ethylenically unsaturated group such as a vinyl group, an allyl group, or a 1-propenyl group. The polymerizable unsaturated group and the linking bond preferably have a vinyl ether, allyl ether, vinyl ester, or allyl ester structure. Further, the vinyl group and allyl group of vinyl ester and allyl ester are preferably bonded to an oxygen atom of an ester bond.
The alkyl group preferably has 2 to 16 carbon atoms, and more preferably 3 to 10 carbon atoms. The structure of the alkyl group is preferably a linear alkyl group or a branched alkyl group, and may have a cyclic structure such as a cyclopentyl group or a cyclohexyl group in the molecule, and a branched alkyl group is more preferable. When a weak solvent described later is used as the organic solvent (D), a branched alkyl group having 3 to 10 carbon atoms is particularly preferable because the solubility of the fluoropolymer (A) in the weak solvent is good.

Monomers that form the unit (A3) by polymerization include vinyl ethers such as ethyl vinyl ether, butyl vinyl ether, 2-ethylhexyl vinyl ether, and cyclohexyl vinyl ether; allyl ethers such as ethyl allyl ether, butyl allyl ether, and cyclohexyl allyl ether; Vinyl esters such as vinyl acetate, vinyl pivalate, vinyl benzoate and vinyl versatate; allyl esters such as allyl acetate, allyl pivalate, allyl benzoate and allyl versatate are preferred. When the weak solvent described later is used as the organic solvent (D), the monomer forming the unit (A3) improves the solubility of the fluoropolymer (A) in the weak solvent. -Ethylhexyl vinyl ether and vinyl versatate are particularly preferred.

When the unit (A3) is contained in the fluoropolymer (A), the ratio of the unit (A3) to the whole unit is preferably 0 to 70 mol%, more preferably 0 to 65 mol%. When the proportion of the unit (A3) is 0 mol%, it means that the unit (A3) is not included. However, when the unit (A3) is included, the lower limit is more than 0 mol%, and 0.01 mol% Is preferred. When the proportion of the unit (A3) is within this range, sufficient weather resistance of the coating film is ensured.
The unit (A3) may be only one type or a combination of two or more types.
When the fluoropolymer (A) has the unit (A3), the adhesion between the coating film of the obtained coating and the substrate is improved, and the coating film becomes flexible, which is preferable.

[Units based on hydroxyl group-containing monomer (A4)]
The preferable thing of the hydroxyl-containing monomer in the unit (A4) based on a hydroxyl-containing monomer is the same as the preferable thing of the hydroxyl-containing monomer used when forming the said unit (A2). The hydroxyl group-containing monomer in the unit (A4) based on the hydroxyl group-containing monomer is more preferably the same as the hydroxyl group-containing monomer used when forming the unit (A2).
As described above, the unit (A4) based on the hydroxyl group-containing monomer is subjected to the step (i-2) while containing the unreacted hydroxyl monomer in the step (i-1) of the method (i). In the step (ii-2) of ii), it is obtained by reacting with the isocyanate group of the compound (1a) to modify less than 100 mol% of the hydroxyl group, or a hydroxyl group-containing monomer separately during the polymerization of the fluoropolymer (A) It is preferable to obtain by adding and copolymerizing.

When the unit (A4) is contained in the fluoropolymer (A), the ratio of the unit (A4) to the whole unit is preferably 0 to 30 mol%. When the unit (A4) is included, the lower limit is more than 0 mol%, and preferably 0.01 mol%. If the ratio of a unit (A4) is this range, sufficient stability of a fluoropolymer (A) can be ensured, and the solubility to an organic solvent will also become favorable.
The unit (A4) may be only one type or a combination of two or more types.
When the fluoropolymer (A) has a unit (A4), the adhesion between the obtained coating film and the substrate is preferably improved.
The fluoropolymer (A) obtained by the method (i) or the fluoropolymer (A) obtained by the method (ii) may be the whole of the fluoropolymer (A). The total ratio of the unit (A2) and the unit (A4) to the unit is preferably 1 to 60 mol%, and more preferably 3 to 50 mol%.

[Other units]
The fluoropolymer (A) in the present invention may contain other units in addition to the units (A1) to (A4) (hereinafter referred to as “other units”).
The monomer forming the other unit is preferably a monomer composed of a non-fluorine compound, and is preferably a monomer having no hydrolyzable silyl group, hydroxyl group, alkyl vinyl ether group or alkyl vinyl ester group. Specifically, non-fluorinated olefins such as ethylene, propylene, n-butene and isobutene; unsaturated carboxylic acids such as vinyl acetic acid and (meth) acrylic acid; vinyl benzoate, vinyl para-t-butylbenzoate, etc. Non-fluorinated aromatic group-containing monomers: nitrogen-containing monomers such as aminopropyl vinyl ether, diethylaminoethyl vinyl ether, 1-vinyl-2-pyrrolidone, 1-vinylimidazole, methacrylamide, and acrylamide: vinyl phosphoric acid, vinyl phosphoric acid dimethyl ester A phosphorus-containing monomer such as is preferable.
When other units are contained in the fluoropolymer (A), the ratio of the other units to the total units is preferably 0 to 5 mol%. Other units may be only one type or a combination of two or more types.

[Composition of Fluoropolymer (A)]
The fluoropolymer (A) in the present invention is a polymer containing the unit (A1) and the unit (A2) as essential units, and optionally containing the unit (A3), the unit (A4), and other units. It is preferable.
As the proportion of each unit constituting the more preferred fluoropolymer (A), the proportion of the unit (A1) with respect to the total units is preferably 10 to 90 mol%, as described above, and preferably 30 to 70 mol. % Is more preferable. The ratio of the unit (A3) to the total unit is preferably 5 to 50 mol%, more preferably 10 to 30 mol%. As described above, the total ratio of the unit (A2) and the unit (A4) to the total unit is preferably 1 to 60 mol%, and more preferably 3 to 50 mol%. Further, the ratio of the unit (A2) to the total unit is preferably within the range of the preferable ratio of the total of the unit (A2) and the unit (A4) and is 1 to 40 mol%. ) And the unit (A4), and more preferably 3 to 25 mol%. The total ratio of units (A1) to (A4) with respect to all units is preferably 95 to 100 mol%, and more preferably 100 mol%.

Preferred unit combinations include CTFE units / unit (A2) / polymer of alkyl vinyl ether units, CTFE units / unit (A2) / hydroxyalkyl vinyl ether units / alkyl vinyl ether units polymer, A polymer of CTFE units / unit (A2) / alkyl vinyl ester units is preferred. Moreover, the combination which contains 1 or more types of a unit (A3), a unit (A4), and another unit further in these combinations is also preferable.

The proportion of each unit constituting the fluorinated polymer (A) is the proportion of each monomer charged in the polymerization reaction for obtaining the fluorinated polymer (A), the reaction conditions, the fluorinated polymer (A) and the compound ( It can be changed depending on the charging ratio and reaction conditions when reacting 1a).

[Fluorine content of fluorine-containing polymerization (A)]
10 mass% or more is preferable, as for the fluorine content of the fluoropolymer (A) in this invention, 20 mass% or more is more preferable, and 25 mass% or more is further more preferable. When the fluorine content is large, the weather resistance of the paint becomes good.
On the other hand, the fluorine content of the fluoropolymer (A) is preferably 35% by mass or less. If the fluorine content is within this range, the solubility of the fluoropolymer (A) in the solvent can be sufficiently secured.

[Polymerization method of fluoropolymer (A)]
The step (i-2) and the step (ii-1) can be performed by a known method. For example, a normal radical polymerization method can be employed, and as the polymerization form, solution polymerization, suspension polymerization, emulsion polymerization, or the like can be employed.

The reaction temperature during the polymerization is appropriately changed depending on the radical polymerization initiator to be used, but it is usually preferably 0 to 130 ° C. The reaction time is preferably between 1 and 50.
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; ether solvents such as cyclopentyl methyl ether can be used.

Examples of the radical polymerization initiator include peroxydicarbonates such as diisopropyl peroxydicarbonate and di-n-propyl peroxydicarbonate; 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 Id like; dicumyl peroxide, dialkyl peroxides such as di -t- butyl peroxide and the like can be used.

In the case of emulsion polymerization, 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.
In step (i-2), since a trace amount of hydrochloric acid or hydrofluoric acid may be generated during the polymerization reaction, it is preferably removed with a buffer after the polymerization reaction.

Examples of the copolymer having a hydroxyl group in the side chain obtained in step (ii-1) include Lumiflon (manufactured by Asahi Glass Co., Ltd., trade name), fluonate (manufactured by Dainippon Ink Chemical Co., Ltd., trade name), It is also possible to use commercially available fluororesins such as Cefral Coat (manufactured by Central Glass Co., Ltd., trade name), Zaflon (manufactured by Toagosei Co., Ltd., trade name), Zaffle (trade name, manufactured by Daikin Industries, Ltd.), etc. it can.

The fluorine-containing polymer (A) preferably has a number average molecular weight (Mn) of 5,000 to 20,000 as measured by gel permeation chromatography (GPC) using polystyrene as a standard substance. When Mn is 5000 or more, good weather resistance of the coating film is easily obtained. Further, when Mn is 20000 or less, it becomes easy to handle because of an appropriate viscosity. In addition, if the viscosity of the fluoropolymer (A) is appropriate, a small amount of dilution solvent is required for coating (viscosity adjustment), so the environmental load is reduced.

[Curing agent (B)]
The coating agent composition of this invention contains the compound represented by the following Formula (2) as a hardening | curing agent (B), and / or its partial hydrolysis-condensation product.

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 1 to 4)
In the above formula (2), R ² is a monovalent hydrocarbon group having 1 to 10 carbon atoms. The monovalent hydrocarbon group as R ² may have a substituent. That is, some or all of the hydrogen atoms of the monovalent hydrocarbon group may be substituted with a substituent. R ² is preferably a methyl group, a hexyl group, a decyl group, a phenyl group, or a trifluoropropyl group. When a plurality of R ² are present in one molecule, they may be the same as or different from each other. A plurality of R ² from the viewpoint of the supply of raw materials is preferably the same as each other.
In the above formula (2), X ² is an alkoxy group having 1 to 10 carbon atoms, preferably a methoxy group or an ethoxy group. When ^two or more X2 exists in 1 molecule, you may mutually be same or different. When multiple X ² are different from each other, because the uniformity of the reaction of the coating from the difference film tends to decrease, it is preferable that a plurality of X ² are the same as each other.
In the above formula (2), a is an integer of 1 to 4, preferably 2 to 4.

Specific examples of the compound represented by the formula (2) include tetrafunctional alkoxysilanes such as tetramethoxysilane, tetraethoxysilane, and tetraisopropoxysilane; methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, Trifunctional alkoxysilanes such as phenyltriethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, decyltrimethoxysilane, trifluoropropyltrimethoxysilane; dimethyldimethoxysilane, diphenyldimethoxysilane, dimethyldiethoxysilane, diphenyldiethoxy And bifunctional alkoxysilanes such as silane.
Among these, tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, and phenyltrimethoxysilane are preferable from the viewpoint of curing speed and physical properties of the coating film.

In the curing agent (B), a part or all of the alkoxy group represented by X ² (or the silanol group generated by hydrolysis of the alkoxy group) is a fluoropolymer (A) and / or an organosiloxane chain. A coating film is formed by reacting with the non-fluorinated polymer (E) having the following.
As the curing agent (B), a compound represented by the formula (2) or a partial hydrolysis condensate thereof may be used alone, or a compound represented by the formula (2) and / or a partial hydrolyzate thereof. Two or more of these may be used in combination.

The partial hydrolysis-condensation product of the compound represented by the formula (2) is a compound obtained by partially hydrolyzing and condensing the compound represented by the formula (2). Although its overall structure is not clear, it is a polysilicate ester consisting of a skeleton composed of Si—O bonds and an alkoxy group (or a silanol group formed by hydrolysis of the alkoxy group), and the skeleton is linear However, it may be branched and may have a ring structure.

The method for producing the partial hydrolysis-condensation product of the compound represented by the formula (2) is not particularly limited, and a known method can be appropriately used. For example, it can be obtained by adding water, an acid and / or a solvent to the compound represented by the formula (2), and partially hydrolyzing and condensing it. Such partially hydrolyzed condensates of alkoxysilane compounds are commercially available in different condensation degrees, structures, and types of alkoxy groups. For example, trade names “MKC silicate MS51”, “MKC silicate MS51”, “ Effective silica content such as “MKC silicate MS56”, trade names “M silicate 51”, “ethyl silicate 40”, “ethyl silicate 45” manufactured by Tama Chemical Co., Ltd., or about 28-52% by mass, or Examples include “HAS-1”, “HAS-6”, and “HAS-10” manufactured by Colcoat Co., Ltd., in which these are dissolved in ethanol or isopropanol.
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.

In the coating agent composition of the present invention, the proportion of the fluoropolymer (A) in the total content of the fluoropolymer (A) and the curing agent (B) is 10 to 90% by mass, 20 It is preferably ˜80% by mass, and more preferably 30 to 70% by mass.
When the content of the fluorinated polymer (A) is 10% by mass or more, the flexibility of the coating film becomes sufficient, and problems such as generation of cracks in the coating film and decrease in adhesion are less likely to occur. When the content of the fluoropolymer (A) is 90% by mass or less, the balance between the content of the fluoropolymer (A) and the curing agent (B) is good, the surface hardness of the coating film becomes good, and the graffiti Removability and decontamination are sufficient.

[Phosphate ester curing catalyst (C)]
The coating agent composition of the present invention is a phosphate ester-based curing catalyst for the purpose of accelerating the curing reaction, imparting good chemical performance and physical performance to the cured product, and curing at a low temperature in a short time. (C) is contained.
Specific examples of the phosphoric ester-based curing catalyst (C) include acidic phosphoric esters such as phosphoric monoesters and phosphoric diesters; addition reaction products of acidic phosphoric esters and amines, and the like.

More specifically, an acidic phosphate ester represented by the following formula (3) and having an acid value in the range of 10 to 800 mgKOH / g is preferable. An acidic phosphate ester having an acid value in the range of 100 to 500 mgKOH / g is more preferable. When the acid value of the acidic phosphate is in the range of 10 to 800 mgKOH / g, the pot life of the paint can be sufficiently secured, and the curability of the paint film is improved, resulting in a cured paint film having excellent mechanical properties. Is obtained.

In the formula (3), R ³ is preferably an alkyl group, cycloalkyl group or aryl group having 3 to 10 carbon atoms, and h is preferably 1 or 2.
Specifically, primary alcohols such as n-propanol, n-butanol, n-hexanol, n-octanol, 2-ethylhexanol; isopropanol, 2-butanol, 2-hexanol, 2-octanol, cyclohexanol, etc. Examples thereof include phosphoric monoesters or phosphoric diesters of secondary alcohols.

The trade names “AP-1”, “AP-4”, “DP-4”, “MP-4”, “AP-8”, “AP-10”, “MP-10”, etc., manufactured by Daihachi Chemical Industry Co., Ltd. are preferred. .
If the acid value of the phosphate ester curing catalyst is 10 mgKOH / g or more, the curing rate of the coating film is sufficient, and if the acid value is 800 mgKOH / g or less, the pot life of the paint is sufficient, and the coating workability is improved. improves.

The addition amount of the curing catalyst is usually selected in the range of 0.0001 to 10 parts by mass with respect to 100 parts by mass of the fluoropolymer (A). If the amount of the curing catalyst is 0.0001 part by mass or more, the catalytic effect is sufficiently developed, and if it is 10 parts by mass or less, the finally obtained coating film is not colored. Also, the water resistance is sufficient.
These acidic phosphate esters may be used alone or in combination of two or more.

[Organic solvent (D)]
The organic solvent (D) contained in the coating agent composition of the present invention includes, for example, ketones such as acetone, methyl ethyl ketone, methyl propyl ketone, ethyl butyl ketone, diisobutyl ketone, cyclohexanone, isophorone; methyl acetate, ethyl acetate, n-acetate Esters such as propyl, isopropyl acetate, n-butyl acetate, isobutyl acetate, t-butyl acetate; toluene, xylene, ethylbenzene, aromatic petroleum naphtha, tetralin, turpentine oil, Solvesso # 100 (registered trademark of Exxon Chemical Co., Ltd.) , Aromatic hydrocarbons such as Solvesso # 150 (registered trademark of Exxon Chemical Co., Ltd.); ethers such as dioxan, tetrahydrofuran and cyclopentyl methyl ether; and esters such as propylene glycol monomethyl ether acetate and methoxybutyl acetate. Ether esters; dimethyl sulfoxide, N, N-aprotic polar solvent such as dimethylformamide or the like, an organic solvent can be used that is generally used.

From the viewpoint of reducing environmental impact, it is better to use organic solvents and weak solvents that comply with the PRTR Law and HAPs regulations (organic solvents classified as organic solvents in the classification of organic solvents by the Industrial Safety and Health Act) preferable.
In the present invention, the weak solvent is selected from the group consisting of gasoline, coal tar naphtha, solvent naphtha, petroleum ether, petroleum naphtha, petroleum benzine, turpentine oil, mineral spirit, mineral thinner, petroleum spirit, white spirit, and mineral turpentine. At least one solvent.
As a solvent corresponding to the PRTR method and HAPs regulations, it is preferable to use an ester solvent or a ketone solvent that does not contain an aromatic group. Moreover, as a weak solvent, it is preferable to use a paraffinic solvent or a naphthenic solvent.

Ketone solvents and ester solvents include ketones such as methyl ethyl ketone, diisobutyl ketone, cyclohexanone and isophorone from the viewpoint of boiling point and resin solubility; methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, n-acetate Esters such as butyl, isobutyl acetate, and t-butyl acetate can be preferably used, but t-butyl acetate, which is a HAPs regulation compliant solvent, is more preferable.

As the organic solvent (D) in the present invention, it is most preferable to use a weak solvent.
By using a weak solvent as the organic solvent (D), it is possible to reduce the influence on the base (old paint film) during repair and the burden on the global environment.
In addition, when a weak solvent is used as the organic solvent (D), it is generally necessary to lower the polarity of the resin, that is, the hydroxyl value, resulting in a decrease in the number of cross-linked sites. The crosslink density decreases and the hardness of the coating film decreases.
However, the fluoropolymer (A) in the present invention has a characteristic that it is easily dissolved in a low-polarity solvent such as a weak solvent while maintaining a sufficient amount of crosslinking sites. Therefore, when the weak solvent is used as the organic solvent (D), the effect of the present invention is most effectively exhibited.

When a weak solvent is used as the organic solvent (D), a solvent having an aniline point of 30 ° C. to 70 ° C. is preferable. The lower limit of the aniline point is more preferably 40 ° C, and the upper limit of the aniline point is more preferably 60 ° C. When the aniline point exceeds 30 ° C, the old coating film is not affected, and if the aniline point is 70 ° C or less, the solubility of the fluorinated copolymer (A) and the curing agent (B) used in the present invention is improved. . The aniline point may be measured according to the aniline point test method described in JIS K 2256.

Further, when a weak solvent is used as the organic solvent (D), a mineral spirit is preferable because the flash point is room temperature or higher. Solvents commonly sold as mineral spirits include, for example, HAWS (manufactured by Shell Japan, aniline point 17 ° C.), Essonaphtha No. 6 (manufactured by ExxonMobil Chemical, aniline point 43 ° C), LAWS (manufactured by Shell Japan, aniline point 44 ° C), Pegasol 3040 (manufactured by ExxonMobil Chemical, aniline point 55 ° C), A solvent (Shin Nippon Petrochemical Co., Ltd., aniline) 45 ° C), Clensol (manufactured by Nippon Petrochemical Co., Ltd., aniline point 64 ° C), Mineral Spirit A (manufactured by Nippon Petrochemical Co., Ltd., aniline point 43 ° C), Hyalom 2S (manufactured by Nippon Petrochemical Co., Ltd.) Aniline point 44 ° C), Hyalom 2S (Shin Nippon Petrochemical Co., Ltd., aniline point 44 ° C), Linearene 10, Linearene 12 (Idemitsu Petrochemical Co., Ltd., α-olefin hydrocarbon, aniline point 44 ° C, 54 ° C) Exol D30 (manufactured by ExxonMobil Co., Ltd., naphthenic solvent, aniline point 63 ° C.), Ricasol 900,910B, 1000 (New Japan Chemical Co., Ltd., hydrogenated C9 solvent, aniline point 53 ℃, 40 ℃, 55 ℃) available as such. These can be used alone or in combination as the weak solvent used in the present invention.

When the coating agent composition of the present invention uses a weak solvent as the organic solvent (D), the weak solvent is used as a polymerization solvent for the fluoropolymer (A) or polymerized in another solvent. It is preferable that a part or all of the solvent or dispersion medium is replaced with a weak solvent later. Further, the concentration of the obtained composition may be adjusted as necessary, or other components may be added to the composition as necessary.

The content of the organic solvent (D) in the coating agent composition of the present invention is appropriately determined in consideration of the solubility of the fluoropolymer (A), the appropriate viscosity when applied as a paint, the coating method, and the like. . The content of the organic solvent (D) is preferably 10 to 150 parts by mass, more preferably 25 to 100 parts by mass with respect to 100 parts by mass of the fluoropolymer (A).
The organic solvent (D) contained in the coating agent composition of the present invention may be only one type or a combination of two or more types.

[Non-fluorine polymer (E) having an organosiloxane chain]
The non-fluorine polymer (E) having an organosiloxane chain (hereinafter sometimes referred to as a non-fluorine polymer (E)) is a polymer having an organosiloxane chain and containing no fluorine atom.
Non-fluorinated polymers (E) include hydroxyl group-containing silicone resins, methoxy group-containing silicone resins, epoxy-modified silicone resins, phenol-modified silicone resins, acrylic-modified silicone resins, polyester-modified silicone resins, alkyd-modified silicone resins, and silicone-modified acrylics. Resin.

These non-fluorinated polymers (E) preferably have a hydroxyl group. Since the non-fluorinated polymer (E) having a hydroxyl group easily reacts with the fluoropolymer (A) and the curing agent (B), the graffiti removing property, the decontamination property, and the water repellency of the coating film are maintained. Conceivable.
More preferably, a hydroxyl group-containing silicone resin and an acrylic modified silicone resin containing a hydroxyl group are used. A silicon-modified acrylic resin containing a hydroxyl group is a graft polymer in which polysiloxane is a side chain and an acrylic polymer is bonded as a main chain.
The hydroxyl group-containing silicone resin and the silicon-modified acrylic resin are excellent in terms of compatibility with the fluoropolymer (A) and the curing agent (B).

The hydroxyl value of the non-fluorinated polymer (E) reacts easily and sufficiently with the fluorinated polymer (A) and the curing agent (B), resulting in a paint film that maintains graffiti removal, contamination removal, and water repellency. Since it can form, it is preferable that it is 30 mgKOH / g or more, and it is more preferable that it is 60 mgKOH / g or more. The hydroxyl value is preferably 200 mgKOH / g or less, preferably 150 mgKOH / g or less in terms of solubility in an organic solvent and compatibility with the fluoropolymer (A) and the curing agent (B). More preferably.

The mass average molecular weight (M _w ) of the non-fluorinated polymer (E) is preferably 1,000 or more and 30,000 or less, and more preferably 5,000 or more and 20,000 or less. When the mass average molecular weight is not less than the lower limit of the above range, the decontamination property is excellent. Moreover, when this mass average molecular weight is made below the upper limit of the said range, it is excellent in compatibility with a fluoropolymer (A) and a hardening | curing agent (B).

Examples of the non-fluorine polymer (E) satisfying these preferable conditions include BYK-Silclean 3700 (manufactured by BYK Japan, solid content 25%, hydroxyl value 120 mgKOH / g) and X-22-160AS (Shin-Etsu Chemical Co., Ltd.). Co., Ltd., hydroxyl value 120 mgKOH / g), KF-6001 (manufactured by Shin-Etsu Chemical Co., Ltd., hydroxyl value 62 mgKOH / g), XF42-B0970 (manufactured by Momentive Performance Materials, hydroxyl value 60 mgKOH / g) g).

The content of the non-fluorine polymer (E) in the coating agent composition of the present invention is 0.01 to 20% of the non-fluorine polymer (E) with respect to 100 parts by mass of the fluoropolymer (A). 0 parts by mass is preferable, and 0.1 to 10.0 parts by mass is more preferable. By setting the content of the non-fluorinated polymer (E) to be equal to or higher than the lower limit of the above range, it is possible to form a coating film with good removal of adhering contaminants. It is possible to satisfactorily prevent problems caused by painting.
The non-fluorine polymer (E) in the coating agent composition of the present invention may be used alone or in combination of two or more.

[Other ingredients]
The coating agent composition of the present invention may contain a colorant (pigment or dye), a silane coupling agent for improving the adhesion of the coating film, and the like.
Examples of the pigment include inorganic pigments such as carbon black and titanium oxide, and organic pigments such as phthalocyanine blue, phthalocyanine green, quinacridone red, indanthrene orange, and isoindolinone-based yellow. The titanium oxide is preferably a surface-coated titanium oxide, and the titanium oxide can be obtained under the trade name “PFC-105” manufactured by Ishihara Sangyo Co., Ltd .; the trade name “D-918” manufactured by Sakai Chemical Co., Ltd.

You may add suitably a light stabilizer, a ultraviolet absorber, a matting agent, etc. to the coating agent composition of this invention further as needed.
Examples of the light stabilizer include hindered amine light stabilizers. For example, trade names “MARX LA62” and “MARX LA67” manufactured by Adeka Argus Chemical Co., Ltd .; trade names manufactured by Ciba Specialty Chemicals Co., Ltd. “Tinuvin 292”, “Tinuvin 144”, “Tinuvin-123”, “Tinuvin 440” and the like can be mentioned.
Examples of ultraviolet absorbers include benzophenone compounds, benzotriazole compounds, triazine compounds, and cyanoacrylate compounds. Examples of the compound include “Viosorb130”, “Viosorb582”, “Viosorb583” (manufactured by Kyodo Pharmaceutical Co., Ltd., trade name), “Tinuvin 320”, “Tinuvin 982”, “Tinuvin 1130”, “Tinuvin 400” (above, Ciba Specialty Chemicals, trade name) and the like.
Examples of matting agents include ultra fine powder synthetic silica. When a matting agent is used, an elegant semi-gloss and matte finish can be formed.

A surfactant may be added to the coating composition of the present invention. Surfactants are effective because they can control the surface tension. The surfactant may be any of nonionic type, cationic type, anionic type, ROLEX ASE (made by Daiichi Kogyo Co., Ltd., trade name), “Surflon”, a fluorosurfactant (made by Asahi Glass Co., Ltd., trade name) Acrylic “Modaflow” (manufactured by Monsanto, trade name), “Leo Fat” series (trade name, manufactured by Kao), and the like.
Moreover, you may mix | blend a leveling agent with the coating agent composition of this invention. When a leveling agent is added, the uniformity of the thickness of the coating film can be improved. Examples of the leveling agent include BYK-300 (manufactured by BYK-Chemie, trade name), Floren No. 3 (manufactured by Kyoeisha Chemical Co., Ltd., trade name), Disparon LF 1985 (manufactured by Enomoto Kasei Co., Ltd., trade name) and the like.

In order to keep the storage stability of the coating composition good, a dehydrating agent may be added to the coating composition.
Examples of the dehydrating agent include orthoformates such as trimethyl orthoformate, triethyl orthoformate, tripropyl orthoformate; orthoacetic esters such as trimethyl orthoacetate, triethyl orthoacetate, tripropyl orthoacetate; trimethyl orthopropionate, ortho Orthopropionic acid esters such as triethyl propionate and tripropyl orthopropionate; dimethoxymethane, 1,1-dimethoxyethane, 1,1-dimethoxypropane, diethoxyethane, 1,1-diethoxyethane, 1,1- Acetals such as diethoxypropane; 1-methoxy-1-ethanol, 1-methoxy-1-propanol, 1-methoxy-1-butanol, 1-ethoxy-1-ethanol, 1-ethoxy-1-propanol, 1-methoxy-1-propanol Ethoxy-1-butanol Hemi-acetals and the like.
When a dehydrating agent is blended, the dehydrating agent is added in an amount of 1 to 10 parts by mass with respect to 100 parts by mass of the fluoropolymer.
The blending amount of the other components can be appropriately selected within a range not impairing the effects of the present invention.

The coating agent composition of this invention can be manufactured by mixing the said essential component and the various additives added as needed. The mixing order and addition order are not particularly limited. Moreover, the coating agent composition of the present invention may be used as a one-component type paint containing a curing agent (B), or a two-component type in which the curing agent (B) is added immediately before using the paint. It may be used as a paint.
As a method of coating using the coating agent composition of the present invention, any method such as spray coating, brush coating, dipping method, roll coater, flow coater and the like can be applied.

The coating composition of the present invention is preferably dried and cured at room temperature when forming a coating film, but in some cases, curing may be accelerated by heating. There is no restriction | limiting in particular in the apparatus used for hardening, Hardening apparatuses, such as a closed-type hardening furnace and a tunnel furnace which can be continuously hardened, are employable. The heating source is not particularly limited, and can be performed by a method such as hot air circulation, infrared heating, high frequency heating or the like. The temperature and time required for curing vary depending on the type of catalyst and the like, but curing conditions of about 1 to 10 hours are generally preferred at a temperature in the range of 50 to 150 ° C. More preferably, the curing conditions are in the temperature range of 50 to 80 ° C. for 30 minutes to 2 hours.

When curing is accelerated by heating, the antifouling component (E) is more easily transferred to the surface of the coating film, and the graffiti removal property, contamination removal property, and water repellency of the coating film are improved, and the Tg of the coating film is further increased. Therefore, when wiping away contaminating components with a brush or the like, the coating film is less likely to be damaged.

The material of the article to be painted is not particularly limited, and includes inorganic materials such as concrete, natural stone, and glass; metals such as iron, stainless steel, aluminum, copper, brass, and titanium; organic materials such as plastic, rubber, adhesive, and wood. It is done. Moreover, FRP which is an organic inorganic composite material, resin reinforced concrete, fiber reinforced concrete, etc. are mentioned.
The coating agent composition of the present invention is particularly suitable for application to the surface of an already formed coating film.
Articles to be painted include transportation equipment such as automobiles, trains and aircraft; civil engineering members such as bridge members and steel towers; industrial equipment such as waterproof sheets, tanks and pipes; building exteriors, doors, window gate members, monuments, poles Building materials such as: Road median strips, guardrails, soundproof walls, light-transmitting plates such as polycarbonate, acrylic, etc .; communication equipment; electrical and electronic parts; solar cell backsheets, solar cell surface protection paints, etc. It is done.

EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to these Examples.
In the following examples, the fluoropolymer (A) may be referred to as component A, and the curing agent (B) may be referred to as component B. Other components may be described in the same manner.

<Production Example 1: Production of mineral spirit solution of fluoropolymer (α1)>
According to the said method (ii), the mineral spirit solution of the fluoropolymer ((alpha) 1) was manufactured as follows.

In an autoclave with a stainless steel stirrer having an internal volume of 3000 mL, cyclohexyl vinyl ether (284.5 g), 2-ethylhexyl vinyl ether (202.9 g), hydroxybutyl vinyl ether (90.7 g), xylene (722 g), ethanol (189 g), Potassium carbonate (9.5 g) was added all at once, and dissolved oxygen was removed with nitrogen.

Next, chlorotrifluoroethylene (505 g) was introduced into the autoclave and the temperature was gradually raised. After reaching 65 ° C., a 50% xylene solution of t-butyl peroxypivalate (7 g) was added over 7 hours. The reaction was stopped after introduction into an autoclave and further stirring for 15 hours.

To a xylene solution of a hydroxyl group-containing fluoropolymer obtained by removing potassium carbonate by filtration, 3-isocyanatopropyltriethoxysilane (154.5 g) and tin octylate (0.5 g) were added. The reaction was carried out at 50 ° C. for 5 hours. Further, the solvent was replaced with mineral spirit while evaporation to obtain a mineral spirit solution (nonvolatile content: 62.5%) of the fluoropolymer (α1).

When the infrared absorption spectrum of the obtained solution was measured, the absorption peak observed in the isocyanate group absorption band was small, and conversely the large absorption peak was observed in the urethane bond absorption band. Formation of (α1) was confirmed.
The composition of the obtained fluoropolymer (α1) is composed of CTFE units / cyclohexyl vinyl ether units / 2-ethylhexyl vinyl ether units / hydroxybutyl vinyl ether units / hydroxybutyl vinyl ether unit hydroxyl groups and 3-isocyanatopropyltrimethoxy. Units reacted with isocyanate groups of silane = 50/26/15/4/5 mol%.

<Production Example 2: Production of t-butyl acetate solution of fluoropolymer (α2)>
According to the above method (ii), a fluoropolymer (α2) t-butyl acetate solution was produced as follows.

To a xylene solution of a hydroxyl group-containing fluoropolymer obtained by removing potassium carbonate by filtration, 3-isocyanatopropyltriethoxysilane (154.5 g) and tin octylate (0.5 g) were added. The reaction was carried out at 50 ° C. for 5 hours. Further, the solvent was replaced with t-butyl acetate while evaporating to obtain a t-butyl acetate solution (nonvolatile content: 62.5%) of the fluoropolymer (α2).

When the infrared absorption spectrum of the obtained solution was measured, the absorption peak observed in the isocyanate group absorption band was small, and conversely the large absorption peak was observed in the urethane bond absorption band. Formation of (α2) was confirmed.
The composition of the obtained fluoropolymer (α2) was the same as that of the fluoropolymer (α1) described in Production Example 1.

<Comparative Production Example 1: Production of fluoropolymer β>
A mineral spirit solution of a fluoropolymer having no group (1) was produced.
That is, a xylene solution of a hydroxyl group-containing fluoropolymer was obtained in the same manner as in Production Example 1. This hydroxyl group-containing fluoropolymer was designated as fluoropolymer β. That is, solvent evaporation into mineral spirits was performed while evaporating the xylene solution of the obtained hydroxyl group-containing fluoropolymer to obtain a mineral spirit solution (nonvolatile content 60.0% by mass) of fluoropolymer β.

<Comparative Production Example 2: Production of xylene solution of fluoropolymer δ>
In an autoclave with a stainless steel stirrer having an internal volume of 3000 mL, cyclohexyl vinyl ether (179.3 g), ethyl vinyl ether (96.6 g), hydroxybutyl vinyl ether (100.7 g), xylene (587.6 g), ethanol (189 g), potassium carbonate (9.5 g) was added all at once, and dissolved oxygen was removed by nitrogen.

Next, chlorotrifluoroethylene (505 g) was introduced into the autoclave and the temperature was gradually raised. After reaching 65 ° C., a 50% xylene solution of t-butyl peroxypivalate (7 g) was added over 7 hours. It introduced into the autoclave and polymerized. Thereafter, the reaction was further continued for 15 hours to complete the reaction. After completion of the reaction, potassium carbonate was removed by filtration and deethanol was performed to obtain a xylene solution (non-volatile content: 60.0%) of the fluoropolymer (δ).
The composition of the obtained fluoropolymer (δ) was CTFE units / cyclohexyl vinyl ether units / ethyl vinyl ether units / hydroxybutyl vinyl ether units = 55/18/17/11 mol%.

(Examples 1 to 4, Comparative Examples 1 and 2)
Using the raw materials shown in Table 1 at the blending ratios (unit: parts by mass) shown in Table 1, a coating agent composition containing a titanium oxide pigment was prepared.
Further, mineral spirits were added so that the viscosity by an Iwata cup (viscosity adjusting device) was 25 seconds to obtain a white enamel paint. The obtained white enamel paint was applied to the surface of a chromate-treated aluminum plate so as to have a film thickness of 50 μm, and was cured in a thermostatic chamber at 25 ° C. for 1 week. Then, the test board with a coating film was created by making it dry in 80 degreeC oven for 1 hour. About the test plate with a coating film thus obtained, “specular gloss of coating film”, “contact angle of coating film”, “weather resistance of coating film”, “repellency of oil-based ink”, “removability of oil-based ink” ”And“ carbon contamination ”were evaluated by the following test methods. The results are shown in Table 1.
The numerical values described in parentheses as the numerical values of the A component and the comparative component in Tables 1 and 2 are nonvolatile amounts, and the ratio of the A component to the total content of the fluorinated copolymer (A) and the B component (A A component amount in / (A + B), unit: mass%) is a value calculated using the nonvolatile content.

The materials and their abbreviations used in Table 1 below are as follows.
“AP-8”: A mixture of mono-2-ethylhexyl phosphate and di-2-ethylhexyl phosphate (manufactured by Daihachi Chemical Industry Co., Ltd.).
“D-918”: Titanium oxide pigment (manufactured by Sakai Chemical Co., Ltd.).
“BYK-300”: Leveling agent (manufactured by BYK-Chemie).
“BYK-Silclean 3700”: a hydroxyl group-containing silicon-modified acrylic resin (BYK-Chemie).
“X-22-160AS”: hydroxyl group-containing silicone resin (manufactured by Shin-Etsu Chemical Co., Ltd.).

[Test method]
1. Mirror gloss of the coating film Measured according to JIS Z 5400 7.6.
2. Contact angle of coating film Using a FACE contact angle meter CA-A type (manufactured by Kyowa Interface Chemical Co., Ltd.), ion-exchanged water and hexadecane droplets were adjusted to 0.005 ml each, and the coating film of each specimen The contact angle of was measured. In Table 1, a contact angle 1 is a contact angle with respect to ion-exchanged water, and a contact angle 2 is a contact angle with respect to hexadecane.
3. Oil-based ink repellency Doodles of red and black oil-based inks are made on the coatings of each test specimen, and the repellency of oil-based inks is evaluated as “○”. “×” and the middle of the evaluation were evaluated as “Δ”. Furthermore, the same repellency was evaluated after wiping the test plate with ethanol 50 times.
4). Removability of oil-based ink Doodles with red and black oil-based inks were made on the coating film of each test specimen, held in an oven at 50 ° C for 1 hour, and then wiped as BEMCOT (trade name, manufactured by Ozu Sangyo Co., Ltd.) Was wiped dry.
The case where oil-based ink was completely removed by dry wiping was evaluated as “◯”, the case where it could hardly be removed was evaluated as “X”, and the middle was evaluated as “Δ”.
5). Carbon contamination test Carbon suspension water (dispersion liquid dispersed in paint shaker for 2 hours by adding glass beads to 5 parts of Carbon Black FW200 from Degussa Huls and 95 parts of deionized water) It was dropped with a dropper until 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 water under running water until the soiled material did not fall off. After washing, it was dried at room temperature for 3 hours, the degree of stain was measured with a color difference meter, the difference in lightness (ΔL ^* ) of the coating film before and after the test was determined, 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} ))
○: Lightness difference −5 or more Δ: Lightness difference −10 or more, less than −5 ×: Lightness difference −10 or less Weather resistance of the coating film A test plate with a coating film was installed outdoors in Naha City, Okinawa Prefecture. The surface gloss of the coating film immediately before installation and two years later was measured by 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:%). The weather resistance was evaluated according to the following criteria.
○: Gloss retention 80% or more.
Δ: Gloss retention 60% or more and less than 80%.
X: Gloss retention less than 60%.

As shown in Table 1, in Examples 1 to 4, high gloss coatings were obtained. In addition, both the contact angles 1 and 2 were large, and the repelling property, removability, and carbon contamination removability with respect to the oil-based ink were excellent. Even after wiping the surface of the coating film with ethanol, it was confirmed that the repellency against oil-based ink was good and there was no problem in terms of durability. Furthermore, the weather resistance was also good.
On the other hand, in Comparative Examples 1 and 2, although the weather resistance was excellent, the repellency, removability, and carbon contamination removability by the oil-based ink were insufficient.

In addition, the entire contents of the specification, claims and abstract of Japanese Patent Application No. 2009-048229 filed on March 2, 2009 are incorporated herein as the disclosure of the specification of the present invention. It is.

Claims

The following fluoropolymer (A), a curing agent (B) comprising a compound represented by the following formula (2) and / or a partially hydrolyzed condensate thereof, a phosphate ester-based curing catalyst (C), an organic solvent (D ), And a non-fluorine polymer (E) having an organosiloxane chain.
Fluoropolymer (A): A fluoropolymer comprising a repeating unit (A1) based on a fluoroolefin and a repeating unit (A2) having a group represented by the following formula (1).
—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.)
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 1 to 4)
The repeating unit (A2) is a repeating unit based on a monomer comprising a reaction product of a hydroxyl group of a hydroxyl group-containing monomer and an isocyanate group of a compound represented by the following formula (1a), or a repeating unit obtained by polymerizing a hydroxyl group-containing monomer. The coating agent composition according to claim 1, which is a repeating unit obtained by reacting the isocyanate group of the compound represented by the following formula (1a) with the hydroxyl group.
OCN (CH 2 ) m SiX 1 n R 1 3-n (1a)
(In the formula, R 1 , X 1 , n, and m are as described above.)
The curing agent (B) represented by the formula (2) is 10 to 200 parts by mass and the phosphoric ester-based curing catalyst (C) is 0.01 to 100 parts by mass of the fluoropolymer (A). The coating agent composition according to claim 1 or 2, comprising 10 parts by mass, 10 to 150 parts by mass of the organic solvent (D), and 0.01 to 10 parts by mass of the non-fluorinated polymer (E) having an organosiloxane chain. object.
The fluoropolymer (A) is a repeating unit (A3) based on a monomer in which an alkyl group and a polymerizable unsaturated group are linked by an ether bond or an ester bond together with the repeating unit (A1) and the repeating unit (A2). The coating agent composition according to any one of claims 1 to 3, which is a polymer comprising a repeating unit (A4) based on a hydroxyl group-containing monomer.
The ratio of the repeating unit (A1) to the total content of the repeating unit (A1) and the repeating unit (A2) in the fluoropolymer (A) is 10 to 99 mol%, and the ratio of the repeating unit (A2) is 1 to 90 mol%, and the ratio of the total of repeating units (A1) and repeating units (A2) is 30 to 100 with respect to the total content of all repeating units in the fluoropolymer (A). The coating agent composition according to claim 4, wherein the composition is a mol%, the proportion of the repeating unit (A3) is 70 to 0 mol%, and the proportion of the repeating unit (A4) is 30 to 0 mol%.
The coating agent composition according to any one of claims 1 to 5, wherein the phosphate ester-based curing catalyst (C) is an acidic phosphate ester compound having an acid value of 10 to 800 mgKOH / g.
The coating agent composition according to any one of claims 1 to 6, wherein the organic solvent (D) is a weak solvent.
The coating agent composition according to any one of claims 1 to 7, wherein the non-fluorine polymer (E) having an organosiloxane chain has a hydroxyl value of 30 to 200 mgKOH / g.
The non-fluorinated polymer (E) having an organosiloxane chain is at least one selected from the group consisting of a silicone resin, a silicone-modified epoxy resin, a silicone-modified phenol resin, a silicone-modified acrylic resin, and a silicone-modified polyester resin. The coating agent composition according to any one of claims 1 to 8.
The coating agent composition according to any one of claims 1 to 9, comprising titanium oxide.
A method for producing a cured coating film, wherein the coating agent composition according to any one of claims 1 to 10 is applied to the surface of an article and cured.
A coated article having a cured coating film formed from the coating agent composition according to any one of claims 1 to 10 on the article surface.