JP2002212491A - Coating agent and structural body using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polymeric coating agent comprising an ultraviolet- absorbing unit and a stainproof unit, and a structural body using the same, which is excellent in light resistance, stainproof properties, durability and transparency. SOLUTION: The coating agent is prepared by adding a polyisocyanate-based hydrophilic crosslinking agent (E) to a copolymer of a monomer composition comprising at least one ultraviolet-absorbing monomer (A) selected from a benzophenone-based ultraviolet-absorbing monomer and a benzotriazole-based ultraviolet-absorbing monomer, a hydrophilic monomer (B), a functional monomer (C) and a copolymerizable vinyl monomer (D). The coating agent is applied on a structural body and properly heat-treated to obtain the structural body on which a film prepared from the coating agent of the invention is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a polymer type coating agent and a structure coated with the same. More specifically, the present invention relates to a coating agent excellent in light resistance, stain resistance, durability and transparency, and a structure coated with the coating agent.

[0002]

2. Description of the Related Art Conventionally, agricultural houses, outdoor water storage tanks,
There has been proposed a method of protecting structures such as electric appliances and tents such as plastics from deterioration or contamination by light (ultraviolet light). For example, JP-A-6-145598 discloses a polyurethane resin obtained by reacting a compound containing two or more active hydrogen atoms with an oxyalkylene group in which a hydrogen atom is substituted by a fluorine atom and a polyisocyanate. The aqueous coating agent is disclosed in JP-A-7-224127.
Japanese Patent Application Laid-Open Publication No. H11-163873 proposes a coating agent comprising a copolymer of polymethylsilsesquioxane and a vinyl monomer such as a carboxylic acid group and a sulfonic acid group. Japanese Patent Application Laid-Open No. Hei 9-220794 discloses an agricultural coating material in which a coating layer mainly composed of an ultraviolet absorbing acrylic resin and an inorganic hydrophilic colloid substance is provided on the surface of a plastic film. Has proposed an agricultural film or the like in which a thermoplastic resin film such as an acrylic resin mixed with an ultraviolet absorber is provided on the surface of a PET film.

[0003] However, the above-mentioned water-repellent polymers (such as silicone resins and fluororesins) are excellent in water repellency and antifouling property, but have a disadvantage of poor light resistance. There is also a proposal that mixes and applies a UV absorber to a water-repellent polymer to achieve both light resistance and antifouling properties.However, by mixing the UV absorber with the water-repellent polymer, the water-repellent effect is improved. There are problems such as a decrease as compared with a single film. In addition, although the method of adding an ultraviolet absorber to a polymer is effective in a short period of time, there is a problem that the ultraviolet absorber bleeds out of the polymer over time, and the effect of light resistance gradually disappears. Therefore, at present, a coating agent capable of simultaneously satisfying light resistance and antifouling property has not been obtained.

Further, as a method of imparting antifouling properties, a method of forming a water-repellent / oil-repellent film so as to prevent contaminants such as dust and tar from adhering to these films is often used. However, it is difficult to completely prevent all the contaminants from adhering, and there is a disadvantage that the contaminants gradually accumulate, and the film surface is mechanically cleaned in a relatively short period of time. Need to remove accumulated pollutants.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a coating agent having long-term light resistance and antifouling property, and a structure using the same, in order to solve the above-mentioned conventional problems. .

[0006]

In order to achieve the above object, a coating agent of the present invention comprises a benzophenone type ultraviolet absorbing monomer represented by the following formula (Formula 4) and a benzophenone represented by the following formula (Formula 5). Contains a copolymer of a monomer composition containing, as essential components, at least one ultraviolet absorbing monomer (A) selected from triazole-based ultraviolet absorbing monomers and a hydrophilic monomer (B) represented by the following formula (Formula 6). It is characterized by doing.

[0007]

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(In the formula (4), R ¹¹ is a hydrogen atom and has 1 carbon atom.
An alkyl group having 1 to 6 carbon atoms or an alkoxyl group having 1 to 6 carbon atoms. R ¹² represents an alkylene group having 1 to 10 carbon atoms or an oxyalkylene group having 1 to 10 carbon atoms, and m ¹ represents 0 or 1. R ¹³ represents a hydrogen atom or a lower alkyl group. X ¹ is an ester bond, an amide bond, an ether bond,
Or a urethane bond. )

[0009]

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(In the formula (5), R^{twenty one}Is hydrogen atom, halogen
Represents an atom or a methyl group. R^{twenty two}Is a hydrogen atom or carbon
Shows the hydrocarbon groups of Formulas 1 to 6. R^{twenty three}Has 1 to 10 carbon atoms
Alkylene group or oxyalkylene having 1 to 10 carbon atoms
Represents a group, m^{twenty one}Represents 0 or 1. R^{twenty four}Represents 1 to 8 carbon atoms
Alkyl groups having 1 to 8 carbon atoms having an amino group
C1-C8 having a kylene group or a hydroxyl group
Represents an alkylene group, m ^{twenty two}Represents 0 or 1. R^{twenty five}Is water
Represents an atom or a lower alkyl group. X^TwoIs an ester bond
Amide bond, ether bond, or urethane bond
You. )

[0011]

Embedded image

(In the formula (6), R ²⁶ represents a hydrogen atom or a lower alkyl group. R ²⁷ represents an alkylene group or a polyoxyalkylene. R ²⁸ represents a hydrogen atom, a lower alkyl group, a carbonyl group or a phenyl group. X ³ represents an ester bond, an amide bond, an ether bond, or a urethane bond.)

In the present invention, the monomer mixture preferably further contains at least one or more functional group-containing monomers (C) selected from hydroxyl group-containing monomers, carboxyl group-containing monomers and amino group-containing monomers. By copolymerizing the above-mentioned UV-absorbing monomer and hydrophilic monomer with a functional group-containing monomer, it is effective in that it reacts with a cross-linking agent to improve the film properties. Specifically, the water resistance of the coating, the adhesion to the substrate, and the like are improved.

In the present invention, the ratio of the ultraviolet absorbing monomer (A), the hydrophilic monomer (B), the functional group-containing monomer (C), and the copolymerizable vinyl monomer (D) is defined as the ratio of the monomer component. (A) / (B) /
(C) / (D) = 5 to 50/10 to 90/1 to 95/5
It is preferably from 50 to 50% by mass. When the monomer constituting the coating agent has such a ratio, not only can it exhibit a high ultraviolet absorbing ability, but also the light resistance and stain resistance of the coating layer can be improved.

In the present invention, the coating agent preferably further contains a polyisocyanate-based hydrophilic crosslinking agent (E). For coating agents,
Further, by containing a polyisocyanate-based hydrophilic cross-linking agent, the functional group contained in the functional group-containing monomer is cross-linked by the hydrophilic cross-linking agent, so that the mechanical strength, water resistance, and weather resistance are maintained without reducing the hydrophilicity of the coating. The property becomes good.

In the present invention, the contact angle of the dried film of the coating agent to water is preferably 65 degrees or less, particularly preferably 60 degrees or less.
If it exceeds 65 degrees, the hydrophilicity decreases, and accordingly, the antifouling performance decreases.

Next, the structure of the present invention is characterized in that a film comprising the above-mentioned coating agent is formed on the surface of the structure.

As described above, in the present invention, since the ultraviolet absorbing monomer, the hydrophilic monomer (antifouling component) and the functional group-containing monomer (coating property improving component) are copolymerized, the ultraviolet absorbing component and The effect is maintained for a long time without bleeding out of the antifouling component from the polymer.

Further, in the present invention, since a hydrophilic monomer is used as an antifouling component, a hydrophilic film is formed, and contaminants adhering to the film are washed away by rain and contaminants are deposited. In addition, antifouling properties can be provided for a long period of time. In other words, when rain or the like comes in contact with the film on which the contaminant adheres, water enters the interface between the contaminant and the antifouling film, and the intruded water gradually lifts the contaminant (rolling up phenomenon). Finally, the contaminants are released from the film together with the polka dots, thereby imparting antifouling properties and providing long-term antifouling performance.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, a polymer-type coating agent is obtained by copolymerizing an ultraviolet absorbing unit, an antifouling unit and a film improving unit, thereby exhibiting light resistance, antifouling property and durability. it can. Among them, the light resistance can be achieved by the ultraviolet absorbing unit of the polymer of the present invention. Antifouling properties can be achieved with the antifouling units of the polymers of the present invention. The durability can be achieved by the UV-absorbing unit and the antifouling unit of the polymer of the present invention, and crosslinking by a functional group-containing monomer and a hydrophilic crosslinking agent.

Next, each component of the polymer of the present invention will be described in detail.

In the present invention, the UV-absorbing monomer (A) is at least one selected from the benzophenone-based UV-absorbing monomer represented by the formula (4) and the benzotriazole-based UV-absorbing monomer represented by the formula (5). Is used.

In the formula (4), examples of the alkyl group having 1 to 6 carbon atoms (R ¹¹ ) include a methyl group, an ethyl group,
Examples thereof include a propyl group, an isopropyl group, a butyl group, an s-butyl group, a t-butyl group, a pentyl group and a hexyl group, and preferably have 1 to 4 carbon atoms (more preferably 1 to 4 carbon atoms).
And the alkyl group 2). Examples of the alkoxy group having 1 to 6 carbon atoms (R ¹¹ ) include a methoxy group, an ethoxy group, a propoxy group, and a butoxy group, and preferably have 1 to 4 carbon atoms (more preferably 1 to 4 carbon atoms).
And the alkoxyl group of 2).

R ¹¹ may be substituted at any position in the benzene ring substituted by the hydroxyl group, and the substitution position of R ¹¹ is preferably the 3- or 5-position.

In the formulas (4) and / or (5), the alkylene group having 1 to 10 carbon atoms (R ¹² , R ²³ ) includes, for example, a methylene group, an ethylene group, a trimethylene group, a propylene group, Examples thereof include a tetramethylene group, a pentamethylene group, a hexamethylene group, an octamethylene group, and a decamethylene group, preferably an alkylene group having 1 to 6 carbon atoms (more preferably an alkylene group having 1 to 4 carbon atoms). Examples of the oxyalkylene group having 1 to 10 carbon atoms (R ¹² and R ²³ ) include an oxymethylene group, an oxyethylene group, and an oxypropylene group.

R ¹² may be substituted at any position in the benzene ring substituted by the hydroxyl group, and the substitution position of R ¹² is preferably the 4-position or 5-position, and particularly preferably the 4-position. Further, R ²³ may be substituted at any position in the benzene ring substituted by the hydroxyl group. The preferred substitution position of R ²³ is 5-position.

As the lower alkyl group (R ¹³ , R ²⁵ ),
For example, an alkyl group having 1 to 4 carbon atoms can be mentioned, and specifically, an alkyl group having 1 to 4 carbon atoms among the above-mentioned alkyl groups can be mentioned.

A halogen atom (R^{twenty one})
Preferred are fluorine, chlorine, bromine and others.
Or a chlorine atom. R^{twenty one}Is a halogen atom or methyl
In the case of a group, R^{twenty one}Is substituted at any position in the benzene ring
It may be. Preferred R ^{twenty one}As a hydrogen atom
Can be

In the hydrocarbon group having 1 to 6 carbon atoms (R ²² ), an alkyl group is preferably used as the hydrocarbon group. Such alkyl groups include those having 1 to 6 carbon atoms among the above-mentioned alkyl groups. R ²² may be substituted at any position in the benzene ring substituted by the hydroxyl group, and the preferred substitution position of R ²² is 3
Rank.

The alkylene group having 1 to 8 carbon atoms (R ²⁴ ) includes, for example, alkylene groups having 1 to 8 carbon atoms among the above-mentioned alkylene groups, preferably 1 to 8 carbon atoms.
To 4 (more preferably 1 to 2) alkylene groups. Examples of the alkylene group having 1 to 8 carbon atoms having an amino group or the alkylene group having 1 to 8 carbon atoms having a hydroxyl group include those in which the alkylene group exemplified above is substituted with an amino group or a hydroxyl group. Can be

X ¹ and X ^{2 each} represent an ester bond, an amide bond, an ether bond, or a urethane bond. Specifically, —COO—, —OCO—, —NHCO—, and —CON
H-, -O-, -NHCOO-, -COONH- and the like. m ¹ , m ²¹ , and m ^{22 each} represent 0 or 1, for example, when m ¹ is 0, X ¹ is directly bonded to the benzene ring substituted by the hydroxyl group without via R ^12. It means you are. When m ²¹ is 0, X
² is a benzene ring substituted with a hydroxyl group,
²³ means that they are directly linked without going through
^{When 22} is 0, it means that X ² is directly bonded to the carbon atom to which R ²⁵ is bonded, not via R ²⁴ . That is, when m ¹ , m ²¹ or m ²² is 0, R
¹² , R ²³ or R ²⁴ is absent. On the other hand, when m ¹ , m ²¹ or m ²² is 1, R ¹² , R
²³ or R ²⁴ is present, for example X ¹
Is bonded to R ¹² .

More specifically, examples of the benzophenone-based UV-absorbing monomer represented by the above formula (4) include 2-hydroxy-4-acryloyloxybenzophenone, 2-hydroxy-4-methacryloyloxybenzophenone, 2-hydroxy -4- (2-acryloyloxy) ethoxybenzophenone, 2-hydroxy-
4- (2-methacryloyloxy) ethoxybenzophenone, 2-hydroxy-4- (2-methyl-2-acryloyloxy) ethoxybenzophenone, and the like.

The benzotriazole type ultraviolet absorbing monomer represented by the above formula (5) includes, for example, 2-
[2'-hydroxy-5 '-(methacryloyloxy)
Phenyl] benzotriazole, 2- [2'-hydroxy-5 '-(acryloyloxy) phenyl] benzotriazole, 2- [2'-hydroxy-3'-t-butyl-5'-(methacryloyloxy) phenyl] benzo Triazole, 2- [2'-hydroxy-3'-methyl-5 '-(acryloyloxy) phenyl] benzotriazole, 2- [2'-hydroxy-5'-(methacryloyloxypropyl) phenyl] -5-chlorobenzo Triazole, 2- [2'-hydroxy-5 '-(methacryloyloxyethyl) phenyl] benzotriazole, 2- [2'-hydroxy-5'-(acryloyloxyethyl) phenyl] benzotriazole, 2- [2
'-Hydroxy-3'-t-butyl-5'-(methacryloyloxyethyl) phenyl] benzotriazole,
2- [2'-hydroxy-3'-methyl-5 '-(acryloyloxyethyl) phenyl] benzotriazole, 2- [2'-hydroxy-5'-(acryloyloxybutyl) phenyl] -5-methylbenzotriazole , [2-hydroxy-3-t-butyl-5- (acryloyloxyethoxycarbonylethyl) phenyl] benzotriazole and the like.

The UV-absorbing monomer (A) comprises a UV-absorbing compound having a 2-hydroxybenzophenone skeleton or a 2-hydroxybenzotriazole skeleton and a functional group (hydroxyl group, carboxyl group, amino group, etc.) and a functional group (hydroxyl group). The compound is prepared by reacting with a copolymerizable vinyl compound having a group, carboxyl group, amino group, etc. (such as acrylic acid or methacrylic acid) and bonding them together (ester bond, amide bond, ether bond, urethane bond, etc.). be able to.

The proportion of the ultraviolet absorbing monomer is 5 to 50% by mass, preferably 20 to 4% by mass, based on the total amount of the monomer components.
0 mass%, particularly preferably 25 to 35 mass%. When the proportion of the monomer is less than 5% by mass, the weather resistance and the ultraviolet-grade ability are reduced, and when it exceeds 50% by mass, the antifouling property is reduced.

The hydrophilic monomer (B) is represented by the following chemical formula (7)
Means a non-functional group-containing copolymerizable vinyl monomer having no functional group such as a carboxyl group or a hydroxyl group. Therefore, in the present invention, among the copolymerizable vinyl compounds, those having a functional group are included in the following functional group-containing monomers (C), and those having no functional group are the hydrophilic monomers (B )include. The hydrophilic monomers (B) can be used alone or in combination of two or more.

[0037]

Embedded image

(In the formula (7), R ²⁶ represents a hydrogen atom or a lower alkyl group. R ²⁷ represents an alkylene group or a polyoxyalkylene. R ²⁸ represents a hydrogen atom, a lower alkyl group, a carbonyl group or a phenyl group. X ³ represents an ester bond, an amide bond, an ether bond, or a urethane bond.)

The hydrophilic monomer (B) is not particularly restricted but includes, for example, alkoxy polyethylene glycol (meth) acrylate, phenoxy polyethylene glycol (meth) acrylate, and other hydrophilic monomers.

The alkoxypolyethylene glycol (meth) acrylate includes, for example, diethylene glycol monomethyl ether acrylate, polyethylene glycol (n = 2 to 25) monomethyl ether acrylate, diethylene glycol monomethyl ether methacrylate, and polyethylene glycol (n = 2 to 25)
Monomethyl ether methacrylate and the like are included. As a commercially available product, for example, N. Nakamura Chemical Co., Ltd.
K ester M-40G: methoxypolyethylene glycol # 230 methacrylate, NK ester M-90G:
Methoxy polyethylene glycol # 400 methacrylate, NK ester AM-90G: methoxy polyethylene glycol # 400 acrylate, and the like.

The phenoxy polyethylene glycol (meth) acrylate includes, for example, phenoxy polyethylene (n = 2 to 25) glycol acrylate. Examples of commercially available products include NK ester AMP-20G: phenoxydiethylene glycol acrylate manufactured by Shin-Nakamura Chemical Co., Ltd.

Other hydrophilic monomers include β-methacryloyloxyethyl hydrogen succinate, styrenesulfonic acid tri-n-butylamine salt, 4-sulfobutyl methacrylate Na, N-vinyl-2-pyrrolidone, and the like.

Among the above-mentioned hydrophilic monomers, alkoxypolyethylene glycol (meth) acrylate is particularly preferred in that the coating is hydrophilic and the adhesion to the substrate is excellent.

The proportion of the hydrophilic monomer is from 10 to 90% by mass, preferably from 20 to 70% by mass, based on the total amount of the monomer components.
% By mass, particularly preferably 20 to 40% by mass. When the proportion of the monomer is less than 10% by mass, the hydrophilicity of the coating film is reduced, and the antifouling performance is reduced. If it exceeds 90% by mass, the water resistance decreases.

The functional group-containing monomer (C) means a functional group-containing copolymerizable vinyl monomer having a functional group such as a carboxyl group, a hydroxyl group or an amino group. By using such a functional group-containing monomer, the film strength of the coating agent composition and the adhesion to the coated surface (plastic, glass, etc.) can be improved.

The functional group-containing monomer (C) is not particularly restricted but includes, for example, acrylic acid, methacrylic acid, maleic anhydride, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate,
-Hydroxypropyl methacrylate, 4-hydroxybutyl acrylate, diethylene glycol monomethacrylate, polyethylene glycol monomethacrylate, aminoethyl (meth) acrylate, and the like. The functional group-containing copolymerizable vinyl monomer (C) can be used alone or in combination of two or more. Above all, 2-hydroxyethyl acrylate and 2-hydroxyethyl methacrylate are particularly preferred in terms of imparting reactivity and hydrophilicity.

The proportion of the functional group-containing monomer is from 1 to 90% by mass, preferably from 10 to 7% by mass, based on the total amount of the monomer components.
0 mass%, particularly preferably 20 to 50 mass%. When the proportion of the monomer is less than 1% by mass, the crosslink density (molecular weight) is reduced, and the water resistance and the adhesion are reduced.
If it exceeds 90% by mass, the crosslink density increases, the coating strength decreases, the film becomes moro, and the adhesion decreases.

The monomer composition of the present invention may contain one or more other copolymerizable vinyl monomers (D) as long as the object of the present invention is not impaired.
Examples of such a copolymerizable monomer include styrene, acrylate, methacrylate, alkyl vinyl ether, and alkyl vinyl ester.

More specifically, acrylates or methacrylates include, for example, acrylic acid-C _1-2 alkyl esters such as methyl acrylate and ethyl acrylate, and methacrylic acid-C such as methyl methacrylate and ethyl methacrylate. _1-2 alkyl esters and the like are included. Alkyl vinyl ethers include, for example, C _1-2 alkyl vinyl ethers such as methyl vinyl ether and ethyl vinyl ether. Alkyl vinyl esters include, for example, C _1-3 alkyl vinyl esters such as vinyl acetate, vinyl propionate and vinyl butyrate. Above all,
From the viewpoint of improving the physical properties of the coating, acrylates, methacrylates, and vinyl acetate are preferred, and methyl methacrylate and methyl acrylate are particularly preferred.

The copolymerizable vinyl monomer (D) can be used as long as the effect of the present invention is not impaired.
-50 mass%, preferably 15-45 mass%. The reason for limiting the copolymerization amount in this way is that the copolymerization ratio affects the antifouling property and the physical properties of the coating.

The weight average molecular weight of the coating agent of the present invention is preferably from 10,000 to 100,000.
When the mass average molecular weight is less than 10,000, the ultraviolet absorbent tends to bleed out and the durability tends to decrease, and when the mass average molecular weight is more than 100,000, the compatibility with the resin to be blended decreases and the dried film becomes cloudy. As a result, the appearance tends to decrease.

When the monomer containing a functional group is contained in the monomer composition, a hydrophilic crosslinking agent (E) is added to a copolymer obtained by polymerizing the monomer composition, and It is preferably applied to the surface. By adding the hydrophilic cross-linking agent, the strength, water resistance and weather resistance of the film containing the ultraviolet absorbent are further improved.

As the hydrophilic cross-linking agent (E), a methylol melamine resin, a glyoxal resin, a polyisocyanate-based cross-linking agent and the like can be used, and a polyisocyanate-based cross-linking agent having good adhesion to the structure is preferable. Specifically, a compound having a hydrophilic polar group represented by a polyalkylene oxide derivative or the like in a main chain or a side chain and having a bifunctional or more functional isocyanate group or an epoxy group or an amino group can be used. And polyisocyanates generally referred to as hydrophilic, self-emulsifying, and self-dispersing types. Above all, Duranate WB is antifouling.
40-100 is preferred. Duranate WB40-100 (made by Asahi Kasei Kogyo Co., Ltd.) NCO remaining amount: about 17% Aquanate 100 (made by Nippon Polyurethane Industry Co., Ltd.) NCO remaining amount: about 17% Aquanate 110 (made by Nippon Polyurethane Industry Co., Ltd.) NCO remaining amount: about 20% Takenate WD-720 (manufactured by Takeda Pharmaceutical Co., Ltd.) NCO remaining amount: about 11% Takenate WD-725 (manufactured by Takeda Pharmaceutical Co., Ltd.) NCO remaining amount: about 17% Takenate WD- 730 (manufactured by Takeda Pharmaceutical Co., Ltd.) NCO remaining amount: about 19%

The amount of the hydrophilic cross-linking agent is not particularly limited, and is, for example, 0.5 to 20 parts by mass, preferably 1 to 15 parts by mass, based on 100 parts by mass of the copolymer composition.
It is part by mass, particularly preferably 2 to 10 parts by mass. When the amount of the hydrophilic cross-linking agent is less than 1 part by mass, the mechanical strength of the coating decreases, and when it exceeds 20 parts by mass, the light resistance and stain resistance tend to decrease.

The coating agent of the present invention is prepared by a solution polymerization method,
It can be produced by a usual polymerization method such as a suspension polymerization method and an emulsion polymerization method.

For example, when prepared by a solution polymerization method, a monomer containing an ultraviolet absorbing monomer (A), a hydrophilic monomer (B), and a functional group-containing monomer (C) in a suitable solvent in the presence of a polymerization initiator. The composition may be polymerized.

As the polymerization solvent, for example, methyl acetate,
Ester such as ethyl acetate, benzene, toluene, aromatic hydrocarbons such as xylene, acetone, cyclohexane,
Known solvents such as ketones such as methyl ethyl ketone and ethers such as tetrahydrofuran can be used. Also,
These solvents can be used alone or in combination of two or more.

Known polymerization initiators can be used, such as peroxides such as benzoyl peroxide,
An azo compound such as azobisisobutyronitrile can be used. These polymerization initiators can be used alone or in combination of two or more. The amount of the polymerization initiator used is not particularly limited, but is preferably about 0.05 to 2% by mass of the monomer composition.

In the case of preparation by an emulsion polymerization method, it can be prepared by emulsifying a monomer component using an emulsifier as necessary and conducting emulsion polymerization in the presence of a polymerization initiator. The emulsifier and polymerization initiator used in the polymerization are not particularly limited, and known ones can be used.

It is to be noted that a dye may be added to the monomer composition to produce a colored coating agent to impart design properties. As the dye, DIANIX BLUE
BG-FSNEW (Mitsubishi Kasei Hoechst), DIAN
IX YELLOW G-FS (manufactured by Mitsubishi Kasei Hoechst), DIANIX RED KBN-SE (manufactured by Mitsubishi Kasei Hoechst) and the like.

The coating composition of the present invention may contain additives such as a hydrolysis inhibitor, an antioxidant, an antifungal agent, an antifoaming agent, a pigment, and a vehicle as long as the object of the present invention is not impaired. May be included. Examples of the hydrolysis inhibitor include carbodiimide-based stabacol 1, PC
D (manufactured by BAYER), 4-t-butylcatechol, azodicarbonamide, fatty acid amide and the like. As antioxidants, BHT, Irganox
1010, Irganox1076, Cyanox17
90 and the like. Examples of the fungicide include pentachlorophenol, copper-8-hydroxyquinoline, bis (tri-n-butyltin) and the like. Examples of the antifoaming agent include silicone and pluronic compounds.

The structures of the present invention can be produced by applying the coating agent of the present invention to the surface of various structures to form a film. The coating method is not particularly limited, and a brush coating method, a spray coating method, a dipping method, a flow coating method, or the like can be employed. After the application, heat treatment is appropriately performed to remove the solvent, and a polymer film is formed on the surface of the structure. The thickness of the coating after drying is 1 to 10
It is preferably formed to have a thickness of μm.

The structure suitable for coating the coating agent of the present invention is not particularly limited, and examples thereof include agricultural coating materials, transparent plates, transparent corrugated plates, outdoor storage tanks, electric appliances, tents, outer walls, and various types of structures. Can be used for glass, plastic sheets or films, metals, rubbers, etc., but because of their long-lasting light resistance and antifouling properties, outdoor structures such as buildings, work tents, agricultural houses (greenhouses), bicycles A glass or plastic window of an aircraft or the like is preferable.

Among them, since light resistance and antifouling property are maintained for a long period of time and excellent in transparency, it is particularly suitable for use in agricultural films used in greenhouses for cultivating agricultural crops. Among them, it is most suitable for use in a house or a large house which is used continuously for a long period of 3 to 5 years or more. In the case of producing agricultural films, polyester is formed into a film having a thickness of about 0.01 to 0.5 mm by calendering, T-die method, inflation method, and the like, and then a coating agent is applied to the surface to form a film. To form

The applicable plastics include:
Although not particularly limited, examples thereof include polymethyl methacrylate, polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polypropylene, polyethylene, and polyvinyl alcohol.
The applicable glass is not particularly limited, but is preferably an inorganic glass or a plastic glass, and particularly preferably a plastic glass or a plastic glass window formed into a glass plate with a polymer such as polymethyl methacrylate, polycarbonate, or polyethylene terephthalate.

[0066]

Next, the present invention will be described in detail with reference to examples.

Example 1 2- [2′-hydroxy-5 ′-(methacryloyloxy) phenyl] benzotriazole was placed in a 300 ml separable flask equipped with a Dimroth funnel, a dropping funnel, a thermometer, a nitrogen inlet tube, and a stirrer. 3
0.0 g, methoxypolyethylene glycol # 400 methacrylate (NK ester M-90G, manufactured by Shin-Nakamura Chemical Co., Ltd.) 25 g, 2-hydroxyethyl methacrylate 25 g, methyl methacrylate 20 g, n-dodecyl mercaptan 0.7 g, methyl ethyl ketone 100 g In addition, the temperature is raised to 50 ° C. while blowing nitrogen from a nitrogen inlet tube. Thereafter, 0.3 g of azobisisobutyronitrile dissolved in a small amount of methyl ethyl ketone is added dropwise over 30 minutes, and after completion of the addition, the temperature is raised to 70 ° C., and the reaction is carried out for 8 hours. To this, 0.1 g of dibutyltin dilaurate was added to prepare a low-staining (hydrophilic) high-molecular ultraviolet absorber having a mass average molecular weight of about 32,000.

The molecular weight was determined by liquid chromatography (G
PC). In the GPC, as a column, a product name “TSKGel GMHXL (manufactured by Tosoh Corporation)” × 2 and a product name “TSKGel G2000HX”
L (manufactured by Tosoh Corporation) × 1, tetrahydrofuran as a mobile phase, and a product name “UV-80” as a detector.
00 "and" RI-80000 ". The measurement conditions are a temperature of 40 ° C. and a flow rate of 0.8 ml / min.

The amount of the functional group-containing monomer (crosslinking agent) used was determined by unifying the remaining amount of isocyanate.

(Examples 2 to 7 and Comparative Examples 1 and 2)
A polymer UV absorber was prepared in the same manner as in Example 1, except that the UV-absorbing monomer, hydrophilic monomer and functional group-containing monomer (crosslinking agent) shown in (1) were used.

(Comparative Example 3) Instead of 2-hydroxy-4-methacryloyloxybenzophenone in the composition of Example 1, a benzotriazole ultraviolet absorber (trade name "Tinuvin 327" manufactured by CIBA-GEIGY) is used. Except for the above, a polymer ultraviolet absorber was prepared in the same manner as in Example 1. The product name "Tinuvin 3
27 "is 2- (3,5-di-t-butyl-2-hydroxyphenyl) -5-chlorobenzotriazole.

[0072]

[Table 1]

[Preparation Example 1: Preparation of Test Specimen] 100 parts of the polymeric ultraviolet absorber prepared in Examples and Comparative Examples and 2.7 parts of the following hydrophilic crosslinking agent were mixed, and polyethylene terephthalate having a thickness of 100 μm was mixed. (PET) After coating at a rate of 5 g / m ² on a substrate, it was dried at 100 ° C. for 2 hours to prepare a structure coated with a light-resistant and antifouling paint. The prepared light-resistant and low-staining structure was evaluated by the following method. Table 2 shows the results. Duranate WB40-100 (polyether polyol hexamethylene diisocyanate adduct, manufactured by Asahi Kasei Corporation) Coronate L-45 (trimethylolpropane tolylene diisocyanate adduct, Nippon Polyurethane Industry
Mytec NY215A (trimethylolpropane hexamethylene diisocyanate adduct, Mitsubishi Chemical Corporation)
Made)

(Stain resistance test) The above structure was left in a constant temperature room at 70 ° C. for 30 minutes, sprinkled with carbon black powder, and left for 30 minutes. After cooling at room temperature, the structure contaminated with carbon black is tilted and sprayed with water by spraying (distance 20 cm, number of sprays 50). After the sample was dried at room temperature, contamination was visually observed. ：: Carbon black almost flowed down, and dirt could be removed. Δ: Some stains remain. (Substrate PET level) X: Dirt cannot be removed but only diffused.

(Light Resistance Test) The light-resistant and low-contamination structure prepared in Preparation Example 1 using the ultraviolet absorbent prepared in Examples and Comparative Examples was used as an I-Super UV tester (Iwasaki Electric Co., Ltd.)
20 cycles, with 8 hours of irradiation time and 4 hours of wet time as one cycle, and evaluated according to the following criteria. Evaluation ○: Almost no fading △: The base material is slightly discolored or deteriorated and becomes cloudy ×: The base material is considerably discolored or deteriorated

(Adhesion) The UV-absorbing agent prepared in Example 1 and Comparative Example was prepared and the light-resistant and low-staining structure prepared in Preparation Example 1 was subjected to a grid test (JIS K-5400) and a cellophane (registered trademark). ) Evaluation was made by a peel test. (Adhesive tape used) Rubber tape: Carton No. 640 manufactured by Nichiban Co., Ltd. Acrylic tape: Polyester tape No. 31B manufactured by Nitto Denko Corporation

(Warm Water Resistance) The light-resistant and low-staining structure prepared in Preparation Example 1 with the ultraviolet absorbent prepared in Example 1 and Comparative Example was immersed in 70 ° C. hot water for 24 hours, and then the appearance and protection were measured. Changes in soiling were visually observed.

(Contact Angle) The contact angle was measured under conditions of 23 ° C. × 60% RH using an Elmagoniometer type contact angle measuring device G-1.

[0079]

[Table 2]

As is clear from the results shown in Tables 1 and 2, the PET structure coated with a coating agent containing a high-molecular ultraviolet absorber made of the copolymer of the present invention was resistant to stain, light, and adhesion. The coating agent containing the copolymer of the monomer composition containing no UV-absorbing monomer of the present invention (Comparative Example 2) is inferior in both light resistance and hot water resistance, and is poor in light resistance. The coating agent containing the copolymer of the monomer composition containing no hydrophilic monomer (Comparative Example 1) was inferior in antifouling property and adhesion. In addition, when a non-hydrophilic cross-linking agent that does not swell in water is used (Example 9), the antifouling property is poorer than when a polyisocyanate-based hydrophilic cross-linking agent is used (Examples 1 to 8). there were.

[0081]

As described above, the coating agent of the present invention is obtained by copolymerizing an ultraviolet absorbing monomer, a hydrophilic monomer (antifouling component) and a functional group-containing monomer. Light resistance and antifouling property are maintained for a long time without bleeding out of the fouling component from the polymer. Therefore, a structure such as an agricultural film can be protected from deterioration due to ultraviolet rays. In particular, a coating agent mixed with a polyisocyanate-based hydrophilic cross-linking agent is applied to the structure, and then appropriately heat-treated, whereby the light resistance and antifouling property of the film formed over a long period of time are maintained, and the transparency is also improved. Are better. Furthermore, since the contact angle of the dried film of the coating agent of the present invention with water is as low as 65 degrees or less, contaminants attached to a structure such as a polymer film can be washed away with water or rainwater, and thus can be prevented for a long time. Soil can be maintained.
Therefore, structures coated with the coating agent of the present invention, for example, outdoor water storage tanks, outer wall materials, electrical appliances, automobile steel plates, agricultural houses, etc., are less deteriorated by ultraviolet rays, have good antifouling properties, and have these structures. It is possible to extend the durability of the body itself.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) C08F 226/02 C08F 226/02 C09D 5/00 C09D 5/00 Z 157/08 157/08 157/12 157/12 175 / 04 175/04 F term (reference) 4J038 CG141 CH041 CH141 CH151 CH191 CJ081 CJ131 CR061 DG262 GA02 GA03 GA06 GA09 KA06 MA06 MA09 NA01 NA03 NA05 NA07 NA11 PA06 PB02 PB05 PB07 PC01 PC08 4J100 AB02S AE03A02A04A08A08A08A08A08A02A04A08A08A08A04A04A04A04A04A04A04A04A04A04A04A04A04A04A04A04AE04AE04AE04AE04AE04AE04AE04AE04AE04AE04AE04A04A04A04A04A04A04A04A04A04A04AE04A04E AL08Q AL08R AL09P AM17Q AM17R AN06Q AN06R BA02P BA02Q BA03P BA03R BA04Q BA05Q BA08P BA08Q BA12R BA29P BB01R BC43Q BC43R BC73R CA05 CA06 DA36 DA61 DA62 JA01

Claims (6)

[Claims] A benzopheno represented by the following formula (Formula 1)
UV-absorbing monomer and represented by the following formula (Formula 2)
Selected from benzotriazole UV absorbing monomers
At least one kind of UV-absorbing monomer (A) and a hydrophilic monomer (B) represented by the following formula (Chem. 3) are required.
Contains a copolymer of a monomer composition containing as a component
A coating agent characterized by that: Embedded image(In the formula (1), R¹¹Is a hydrogen atom, an alkyl having 1 to 6 carbon atoms
And a alkoxy group having 1 to 6 carbon atoms. R¹²
Is an alkylene group having 1 to 10 carbon atoms, or 1 to 10 carbon atoms.
An oxyalkylene group of m¹Represents 0 or 1.
R¹³Represents a hydrogen atom or a lower alkyl group. X¹Is d
Stele bond, amide bond, ether bond, or urethane
Indicates binding. )(In the formula (2), R^{twenty one}Represents a hydrogen atom, a halogen atom, or a
Represents a tyl group. R^{twenty two}Is a hydrogen atom or a carbon having 1 to 6 carbon atoms
Shows a hydride group. R^{twenty three}Is alkylene having 1 to 10 carbon atoms
Group, or an oxyalkylene group having 1 to 10 carbon atoms,
m^{twenty one}Represents 0 or 1. R^{twenty four}Is an alkylene having 1 to 8 carbon atoms
An alkylene group having 1 to 8 carbon atoms having an amino group,
Or an alkylene having 1 to 8 carbon atoms having a hydroxyl group
Represents a group, m ^{twenty two}Represents 0 or 1. R^{twenty five}Is a hydrogen atom,
Represents a lower alkyl group. X^TwoIs an ester bond, amide
A bond, an ether bond, or a urethane bond. )(In the formula (3), R²⁶Represents a hydrogen atom or a lower alkyl group
Show. R²⁷Represents an alkylene group or a polyoxyalkylene
You. R²⁸Represents a hydrogen atom, a lower alkyl group, a carbonyl group or
Represents a phenyl group. X^ThreeIs an ester bond or amide bond
A bond represents an ether bond or a urethane bond. ) 2. The coating agent according to claim 1, wherein the monomer mixture further contains at least one or more functional group-containing monomers (C) selected from a hydroxyl group-containing monomer, a carboxyl group-containing monomer and an amino group-containing monomer. 3. The ratio of the ultraviolet absorbing monomer (A), the hydrophilic monomer (B), the functional group-containing monomer (C) and the copolymerizable vinyl monomer (D) is based on the total amount of the monomer components. (A) / (B) / (C) / (D) = 5-5
The coating agent according to claim 1, wherein the coating agent is 0/10 to 90/1 to 95/5 to 50 (% by mass). 4. The coating agent according to claim 1, further comprising a polyisocyanate-based hydrophilic crosslinking agent (E).
4. The coating agent according to any one of 3. 5. The coating agent according to claim 4, wherein a contact angle of the dried film of the coating agent with water is 65 degrees or less. 6. A structure having a coating comprising the coating agent according to claim 1 formed on the surface of the structure.