JPH11146732A - Agricultural fluororesin film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an agricultural fluororesin film excellent in transparency and antifogging persistence. SOLUTION: This fluororesin film is obtained by coating one or both surfaces of a fluororesin film with a coating film derived from an antifogging agent composition consisting essentially of the following three components (A), (B) and (C): (A) a vinylic copolymer comprising the following (a-1) to (a-5): (a-1) a vinylic monomer having a hydrolyzable silyl group and/or an oligomer having the hydrolyzable group and vinyl group, (a-2) a vinylic monomer having an amineimide group, (a-3) a vinylic monomer having hydroxyl group, (a-4) a vinylic monomer having an ionic or an ion-forming group and (a-5) an alkyl (meth) acrylate (having 1-5C alkyl group), (B) an inorganic colloid sol and (C) water and/or a water soluble solvent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an agricultural fluororesin film. More specifically, the present invention relates to a fluororesin film for agricultural use which is excellent in transparency and antifogging durability, in which a coating film is formed using a vinyl copolymer having a hydrolyzable silyl group.

[0002]

2. Description of the Related Art Fluororesin films are excellent in weather resistance, mechanical strength, transparency, etc., and have recently been growing as agricultural covering materials which can be spread over a long period of time, for example, over 10 years. Agricultural fluoroplastic films have been developed. However, when a fluororesin film is used for an agricultural house, water vapor in the house is condensed on the film surface due to low surface tension and adheres as water droplets. There has been a problem in that water droplets drop on the crop surface, causing growth disorders, and failing to function as an agricultural house.

In order to solve this problem, there have been proposed methods of providing various antifogging layers on a fluororesin film.
For example, a method of providing a coating layer or a resin layer containing an antifogging agent (Japanese Patent No. 2535185, Japanese Patent Application Laid-Open No. 7-1684)
JP-A-5-59202 and JP-A-6-145. Alternatively, a method of providing an antifogging layer containing a fine particle inorganic substance and a surfactant and lithium silicate or the like may be used.
389).

[0004]

However, in these methods, the anti-fogging coating is deteriorated by ultraviolet rays, and furthermore, the anti-fogging coating is deteriorated due to the hydrolysis of the anti-fogging coating due to the coagulated water in the house. It is difficult to maintain the antifogging property for a long period of time due to peeling of the coating film and the like, and there are drawbacks such as deterioration of the film appearance (devitrification) due to peeling of the coating film. An object of the present invention is to provide an agricultural fluororesin film excellent in transparency and antifogging durability without the antifogging coating film being deteriorated by ultraviolet rays for a long period of time.

[0005]

The present inventors have conducted various studies to solve the above problems, and as a result, have found that a vinyl copolymer having a hydrolyzable silyl group is used on the surface of a fluororesin film. The inventors have found that the above objects can be achieved by forming a coating film as described above, and have completed the present invention. That is, the gist of the present invention is to provide the following components (A) and (B) on one or both sides of a fluororesin film.
And (C) a coating film derived from an anti-fogging agent composition containing the three components as main components.

(A) A vinyl copolymer comprising the following (a-1) to (a-5) (a-1) A vinyl monomer having a hydrolyzable silyl group and / or a hydrolyzable silyl group And oligomer having a vinyl group (a-2) vinyl monomer having an amine imide group (a-3) vinyl monomer having a hydroxyl group (a-4) vinyl monomer having an ionic group or an ion-forming group (A-5) (meth) alkyl acrylate (alkyl group having 1 to 5 carbon atoms) (B) inorganic colloid sol (C) water and / or water-soluble solvent

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. (1) Fluororesin Film The fluororesin used in the agricultural fluororesin film of the present invention is a general term for synthetic resins obtained by polymerization of olefins containing fluorine, and generally has a fluorine content of 45% by weight in the present invention. %, Especially 50% by weight or more is suitably used. Examples of such a fluororesin include ethylene-tetrafluoroethylene-based copolymer, ethylene-chlorotrifluoroethylene-based copolymer, hexafluoropropylene-tetrafluoroethylene-based copolymer, and perfluoroalkyl vinyl ether-
Tetrafluoroethylene-based copolymer, polyvinylidene fluoride, polyvinyl fluoride and the like can be mentioned, and any of these can be used in the present invention.
Tetrafluoroethylene-based copolymers are preferred.

The ethylene-tetrafluoroethylene copolymer is mainly composed of ethylene and tetrafluoroethylene (the molar ratio of ethylene / tetrafluoroethylene is generally in the range of 40/60 to 60/40). A small amount (usually 10 mol or less) of a third comonomer component is copolymerized. In the present invention, the ethylene / tetrafluoroethylene content molar ratio is 40/60.
６０60/40, preferably 45 / 55-55 / 45, and the third comonomer component has the formula CH ₂ ＣC
_{H-C n F 2n + 1} ( where, n is an integer from 2 to 10 in the formula) perfluoroalkyl vinyl monomer represented by (e.g. _{CH 2 = CH-C 4 F} 9 or CH ₂ = CH-
An ethylene-tetrafluoroethylene copolymer having a C ₆ F ₁₃ ) content of 0.1 to 10 mol%, preferably 0.3 to 5 mol% is suitably used. This ethylene-tetrafluoroethylene copolymer is known per se and can be produced, for example, by the method described in JP-B-59-50163.

Further, in the present invention, the above-mentioned fluororesin may be a mixture with other thermoplastic resins such as polyethylene and polypropylene as long as the effects of the present invention are not impaired. In order to form a film from the above-mentioned fluororesin, a method known per se can be used, for example, by extrusion molding, inflation molding, or the like. The fluororesin composition of the present invention may contain various additives as required. Examples of the additive include organic pigments such as condensed azo type, isoindolinone type, quinacridone type, perylene type, perinone type, quinophthalone type, anthraquinone type, and phthalocyanine type, titanium oxide, titanium yellow, zinc white, iron black, Examples thereof include inorganic pigments such as carbon black, red iron oxide, and ultramarine blue, pigment dispersants, inorganic or organic antibacterial agents, and organic or inorganic ultraviolet absorbers. The thickness of the film is desirably in the range of 10 to 300 μm, particularly 20 to 200 μm. If the thickness of the film is too thin, it is easily broken, and if it is too thick, not only does the transparency deteriorate, but also the product becomes heavy, which may hinder workability (cutting, adhesion, spreading work, etc.) during handling.

The fluororesin film used in the present invention has a surface wetting index (JIS K6768) on the surface on which a coating film is provided.
Is preferably 30 dyn / cm or more. If the wetting index is less than 30 dyn / cm, the adhesion between the coating film and the fluororesin film is poor, and the coating film tends to peel off, which is not preferable. The fluororesin film having a wetting index of less than 30 dyn / cm can be made to have the predetermined wetting index of the present invention by performing a surface treatment. Examples of such a surface treatment method include a corona discharge treatment, a sputter etching treatment, a sodium treatment, a sand blast treatment, and a frame treatment. Among them, corona discharge treatment is preferable from the viewpoint of adhesion between the anti-fog coating film and the fluororesin film, workability, and cost.

(2) Antifoggant composition The hydrolyzable silyl group which is one of the constituent units (a-1) of the component (A) of the present invention includes, for example, a halogenosilyl group, an acyloxysilyl group, an amidosilyl group Groups, aminoxysilyl groups, alkenyloxysilyl groups, aminosilyl groups, oximesilyl groups, alkoxysilyl groups, thioalkoxysilyl groups, etc., with the alkoxysilyl group being preferred. Specific examples of the vinyl monomer having an alkoxysilyl group include vinylsilane [vinylmethyldimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, etc.]; and (meth) acryloxy Alkylsilane [γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-acryloxypropyltrimethoxysilane, γ
-Methacryloxypropylmethyldiethoxysilane, γ
-Acryloxypropyltriethoxysilane, etc.].

The oligomer having a hydrolyzable silyl group and a vinyl group includes, for example, polyurethane having one or more vinyl groups and one or more alkoxysilyl groups,
Oligomers selected from polyethers, polyamides, epoxy resins and polyesters are mentioned. Of these, particularly preferred are (meth) acryloxyalkylsilanes and polyurethane oligomers having a vinyl group and an alkoxysilyl group.

Examples of the vinyl monomer having an amine imide group (a-2) include 1,1,1-trimethylamine methacrylimide, 1,1-dimethyl-1-ethylamine methacrylimide, and 1,1-dimethyl-methacrylate. 1- (2
-Hydroxypropyl) amine methacrylimide, 1,
1-dimethyl-1- (2′-phenyl-2′-hydroxyethyl) amine methacrylimide, 1,1-dimethyl-1- (2′-hydroxy-3′-phenoxypropyl) amine methacrylimide, 1,1, 1-trimethylamine acrylimide and the like. Of these, preferred are 1,1,1-trimethylamine methacrylimide and 1,1-dimethyl-1- (2-hydroxypropyl) amine methacrylimide.

The vinyl monomer having a hydroxyl group in (a-3) is not particularly limited as long as it is a vinyl monomer having a hydroxyl group. Specifically, for example, (meth) acrylic acid
Examples thereof include 2-hydroxyethyl, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and monoester (meth) acrylate of diethylene glycol. Preferably, it is 2-hydroxyethyl (meth) acrylate. Specific examples of the vinyl monomer containing an ionic group or an ion-forming group (a-4) include those that impart cationicity: N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylamide, (meth) acryloyloxyethyltrimethylammonium chloride, (meth) acryloyloxyethyltrimethylammonium chloride, (meth) acryloyloxyethyl Those imparting anionic property such as trimethyl ammonium methosulfate: vinyl carboxylic acid [(meth) acrylic acid, ethacrylic acid, crotonic acid, sorbic acid, maleic acid, itaconic acid, cinnamic acid, etc.], vinyl sulfonic acid [ Vinyl sulfonic acid, allyl sulfonic acid Vinyltoluenesulfonic acid, styrenesulfonic acid, etc.], (meth) acrylsulfonic acid [sulfoethyl (meth) acrylate, sulfopropyl (meth) acrylate], (meth) acrylamidesulfonic acid [2-acrylamido-2-methylpropane] Sulfonic acid, etc.]. Preferred are N, N-dimethylaminoethyl (meth) acrylate and (meth) acrylic acid. (A-
As the (meth) acrylic acid ester having an alkyl group having 1 to 5 carbon atoms of 5), specifically, for example, (meth)
Methyl acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, (meth) acrylic acid-
n-butyl, n-amyl (meth) acrylate and the like. Preferred are methyl (meth) acrylate and n-butyl (meth) acrylate.

As for the content of each structural unit in the vinyl copolymer, (a-1) is usually 0.5 to 50% by weight, particularly 3 to 5% by weight.
30% by weight, (a-2) is usually 0.5 to 50% by weight, particularly 1 to 30% by weight, (a-3) is usually 1 to 40% by weight,
Particularly, 3 to 30% by weight, (a-4) is usually 0.5 to 30% by weight, particularly 1 to 20% by weight, and (a-5) is usually 30 to 9%.
It is preferably 0% by weight, particularly preferably 50 to 80% by weight. However, (a-1) to (a-5) are 100 in total.

If (a-1) is less than 0.5% by weight, the curability of the coating film becomes insufficient, the coating film performance such as water resistance becomes poor, and the antifogging durability is inferior. If it exceeds, the storage stability of the antifogging agent composition becomes poor, which is not preferable.
If (a-2) is less than 0.5% by weight or (a-3) is less than 1% by weight, the storage stability of the antifogging agent composition becomes poor, and gelation easily occurs, which is not preferable. (A-2)
Exceeds 50% by weight or (a-3) is 40% by weight
If it exceeds, there is no effect of improving the storage stability of the antifogging agent composition, and an expensive chemical such as amine imide is used, which is disadvantageous in cost and is not preferred. If (a-4) is less than 0.5% by weight, the dispersibility of the antifogging agent composition will be insufficient, and if it exceeds 30% by weight, the coating properties such as water resistance will be poor and the antifogging durability will be poor. Not preferred. (A-5) is 30
If it is less than 10% by weight, the film performance such as water resistance becomes poor,
If it exceeds 90% by weight, a stable antifogging agent composition cannot be obtained, which is not preferable.

The component (A) of the present invention may be obtained by either a method in which the vinyl copolymer is obtained by solution polymerization and then emulsified and dispersed, or a method obtained by emulsion polymerization. A preferred polymerization method is a solution polymerization method using an initiator in an organic solvent. Examples of the organic solvent used include alcohols (ethanol, isopropanol, n-butanol, etc.), aromatic hydrocarbons (toluene, xylene, etc.), aliphatic hydrocarbons (hexane, cyclohexane, etc.), and aliphatic esters (ethyl acetate, acetic acid). n-butyl, etc.), aliphatic ketones (acetone, methyl ethyl ketone, etc.), aliphatic ethers (dioxane, tetrahydrofuran, etc.) and mixtures of two or more thereof. Preferred are isopropanol, toluene and methyl ethyl ketone alone or a mixture of two or more thereof.

The polymerization initiator may be any one used for ordinary polymerization. For example, peroxides such as benzoyl peroxide, t-butylperoxybenzoate, t-butylperoxy-2-ethylhexanoate, etc. Azo polymerization initiators such as azobisisobutyronitrile, 2,2′-azobis-2,4-dimethylvaleronitrile, and 2,2-azobis-4-methoxy-2,4-dimethylvaleronitrile can be used. .

When the vinyl copolymer is obtained by solution polymerization, the component (A) of the present invention is obtained by emulsification. As a method of this emulsification, there are a method in which the solution is polymerized and then the solution is topped to emulsify the remaining resin, and a method in which water is added to the solution as it is to emulsify and then the solvent is topped. The solvent may or may not remain after emulsification. It is preferable to emulsify in a solution state if possible. In this case, an emulsifier or a pH adjuster may be added for emulsification.
Examples of the emulsifier include anionic surfactants such as an alkyl sulfate salt, an alkylaryl sulfonate salt, an alkyl phosphate ester salt or a fatty acid salt, cationic surfactants such as an alkylamine salt and an alkyl quaternary ammonium salt; Non-ionic surfactants such as ethylene alkyl aryl ether, polyoxyethylene alkyl ether, or pluronic type, and amphoteric surfactants such as carboxylate type (amino acid type, betaine type) or sulfonate type can be used in combination. it can.

In order to improve the cross-linking density after coating film formation and the adhesion to the substrate, silanes can be blended before emulsification and then put into micelles during emulsification. Specific examples of such silanes include, for example, methyltrimethoxysilane, tetramethoxysilane, tetraethoxysilane,
Tetra-n-butoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane,
γ-glycidoxypropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, silicate and the like. When emulsifying the resin solution as it is, after adding these additives to the resin solution, water may be gradually added and emulsified to obtain a water-dispersed resin composition. When the component (A) of the present invention is obtained by emulsion polymerization, a method of using a polymerizable emulsifier and copolymerizing it with each component in an aqueous medium is used. The same initiators as in the case of solution polymerization can be used as the initiator. At the time of emulsion polymerization, another emulsifier or a pH adjuster may be used in combination. These may be the same as in the case of the emulsification described above.

The inorganic colloid sol as the component (B) of the present invention has a function of imparting hydrophilicity by being formed on the surface of the fluororesin film. Examples of the inorganic colloid sol include, for example, silica, alumina, water-insoluble lithium silicate, iron hydroxide, tin hydroxide, titanium oxide, inorganic aqueous colloid particles such as barium sulfate, dispersed in water or a hydrophilic medium by various methods. Aqueous sol. Of these, silica sol is particularly preferred.
These inorganic colloid sols have an average particle diameter of 5 to 100 n.
A range of m is preferred. Within this range, two or more types of colloid sols having different average particle sizes may be used in combination. If the average particle size exceeds 100 nm, not only the transparency of the coating film will deteriorate, but also the antifogging durability will decrease. If it is less than 5 nm, the stability of the inorganic colloid sol may be lacking. The compounding amount of the inorganic colloid sol is 0.5% by weight based on the solid content of the component (A).
It is preferably from 15 to 15, particularly from 0.5 to 10.
When it is less than 0.5, a sufficient anti-fogging effect cannot be exhibited, and when it exceeds 15, not only the anti-fogging effect does not improve in proportion to the blending amount, but also the coating film becomes rough and brittle. It is not preferable because it becomes easy to be formed.

The anti-fogging composition of the present invention may contain, in addition to these essential components, a crosslinking agent for the purpose of improving water resistance. Examples of the crosslinking agent used include phenol resins, amino resins, amine compounds, aziridine compounds, azo compounds, isocyanate compounds, epoxy compounds, silane compounds and the like. Of these, amine compounds, aziridine compounds, and epoxy compounds are particularly preferred. Examples of the amine compounds include aliphatic polyamines such as diethylenetriamine, triethylenepentamine, and hexamethylenediamine; 3,3′-dimethyl-4,4′-diaminodicyclohexylmethane;
Alicyclic amines such as isophoronediamine; and aromatic amines such as 4,4'-diaminodiphenylmethane and m-phenylenediamine are used.

Aziridine compounds include tris-
2,4,6- (1-aziridinyl) -1,3,5-triazine, trimethylolpropane-tri-β-aziridinylpropionate, tris [1- (2-methyl) aziridinyl] triphosphatriazine and the like Is used. Epoxy compounds include reaction products of bisphenol A or bisphenol F with epichlorohydrin, epoxidized novolak resins formed by the reaction of a resin reaction product of phenol (or substituted phenol) with formaldehyde and epichlorohydrin, epichlorohydrin and aliphatic Polyhydric alcohols such as glycerol,
Resinous reaction products produced from 1,4-butanediol, poly (oxypropylene) glycol or similar polyhydric alcohol components, resins obtained by epoxidation using peracetic acid, and the like are used. In the case of epoxy compounds, it is preferable to use a tertiary amine or a quaternary ammonium salt in combination as a catalyst.

These crosslinking agents can be used in an amount of 0.01 to 0.5 in terms of the weight ratio of the solid content of the vinyl copolymer resin having a hydrolyzable silyl group. Particularly preferred is a range of 0.05 to 0.2. The antifogging agent composition of the present invention is blended with component (C), water and / or a water-soluble solvent, and, if necessary, another liquid dispersion medium.
Examples of such a liquid dispersion medium include water; monohydric alcohols such as methyl alcohol, ethyl alcohol, and isopropyl alcohol; polyhydric alcohols such as ethylene glycol and glycerin; cyclic alcohols such as benzyl alcohol; cellosolve acetates; Is raised.
These liquid dispersion media may be used alone or in combination,
It is preferably determined in consideration of the dispersion stability of the antifogging agent composition according to the present invention, the wettability after being applied to the surface of a molded article, the difficulty of removing the liquid dispersion medium, and the economic efficiency.

Further, these antifogging agent compositions preferably contain a hindered amine compound containing at least one structural unit represented by the above general formula (I) in one molecule. Specifically, dimethyl-1- (2-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine succinate polycondensate, poly [{6- (1,1,1)
3,3-tetramethylbutyl) imino-1,3,5-triazine-2,4-diyl {(2,2,6,6-tetramethyl-4-piperidyl) imino {hexamethylene} (2,2 , 6,6-tetramethyl-4-piperidyl)
Imino}], bis (1,2- (3,5-di-t-butyl-4-hydroxybenzyl) -2-n-butylmalonate
2,2,6,6-pentamethyl-4-piperidyl),
1,5,8,12-tetrakis [4,6-bis {N-
(2,2,6,6-tetramethyl-4-piperidyl) butylamino {-1,3,5-triazin-2-yl]-
1,5,8,12-tetraazadodecane, bis (2,
2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1-n-octoxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,
2,2,6,6-pentamethyl-4-piperidyl) sebacate, 1- [2- {3- (3,5-di-t-butyl-
4-hydroxyphenyl) propionyloxy {ethyl] -4- {3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy} -2,2,6
6-tetramethylpiperidine, 4-benzoyloxy-
2,2,6,6-tetramethylpiperidine, 8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-
1,3,8-Triazaspiro [4.5] decane-2,4
-Dione, tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) -1,2,3,4-butanetetracarboxylate, tetrakis (2,2,6,6-tetramethyl-4- Piperidyl) -1,2,3,4-butanetetracarboxylate, bis (1,2,2,6,6
-Pentamethyl-4-piperidyl) di (tridecyl)
-1,2,3,4-butanetetracarboxylate, bis (2,2,6,6-tetramethyl-4-piperidyl)
Di (tridecyl) -1,2,3,4-butanetetracarboxylate, 3,9-bis [1,1-dimethyl-2
-{2,3,4-tris (1,2,2,6,6-pentamethyl-4-piperidyloxycarbonyl) butylcarbonyloxy} ethyl] -2,4,8,10-tetraoxaspiro [5.5 ] Undecane, 3,9-bis [1,
1-dimethyl-2- {2,3,4-tris (2,2,
6,6-tetramethyl-4-piperidyloxycarbonyl) butylcarbonyloxydiethyl] -2,4,8,
10-tetraoxaspiro [5.5] undecane and the like.

Among them, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1-n-octoxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, Bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) -1,2,3,4-butanetetracarboxy Rate, tetrakis (2,2,6,6-tetramethyl-4-
Piperidyl) -1,2,3,4-butanetetracarboxylate, bis (1,2,2,6,6-pentamethyl-
4-piperidyl) di (tridecyl) -1,2,3,4
-Butanetetracarboxylate, bis (2,2,6,
6-tetramethyl-4-piperidyl) .di (tridecyl) -1,2,3,4-butanetetracarboxylate is preferred, and bis (2,2,6,6) is particularly preferred.
-Tetramethyl-4-piperidyl) sebacate, tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) -1,2,3,4-butanetetracarboxylate, tetrakis (2,2,6) 6-tetramethyl-4-
Piperidyl) -1,2,3,4-butanetetracarboxylate, bis (1,2,2,6,6-pentamethyl-
4-piperidyl) di (tridecyl) -1,2,3,4
-Butanetetracarboxylate. These hindered amine compounds may be used alone or in combination of two or more.

The antifogging agent composition of the present invention may further contain, if necessary, an antifoaming agent, a surfactant, a plasticizer, a film-forming aid, a thickener, a pigment, a pigment dispersant, an organic or inorganic material. Conventional additives such as a system ultraviolet absorber can be blended. In order to form the anti-fogging coating film, the anti-fogging film is formed by applying the anti-fogging agent composition on the surface of the fluororesin film, and then forcibly drying or naturally drying and evaporating the liquid dispersion medium. Depending on the use of the film, even if the antifogging coating is formed on both sides,
It may be formed only on one side. As a coating method, a known coating method such as a doctor blade coating method, a roll coating method, a dip coating method, a spray coating method, a rod coating method, a bar coating method, a knife coating method, and a brush coating method can be used.

As a method of forcibly drying, hot air drying is used.
Drying method, infrared radiation method and the like can be adopted. When forced drying
The heating temperature is determined by the applied antifoggant composition
But in the range of 50 to 250 ° C, preferably 60 to 200 ° C.
It is an enclosure. Antifogging agent composition on the surface of fluororesin film
After applying, drying and evaporating the liquid dispersion medium,
Landing amount is 0.01 to 10 g / m^TwoEspecially 0.1 to 5 g /
m ^TwoIs preferably within the range. The agricultural footwear of the present invention
When using plastic film as an agricultural covering material
In the case of a film in which the anti-fog coating film is formed only on one side,
The surface on which the coating is formed will be inside the house or tunnel
And use it as it is.

[0029]

The agricultural fluororesin film of the present invention comprises:
Since the transparency and antifogging durability are remarkably improved, it is effective as an agricultural covering material such as an outer film or an inner film.

[0030]

EXAMPLES Examples 1 to 6 and Comparative Examples 1 to 4 (1) Preparation of Fluororesin Film Trichloromonofuran was added to an autoclave having an internal volume of 10 L.
Oromethane 3.46 kg, trichlorotrifluoroeta
6.52 kg and t-butyl peroxyisobutyrate
Rate of 2.38 g and then tetrafluoroethyl
1226 g of ren, 82 g of ethylene, and perfluoro
Butyl ethylene (CH_Two= CH-C_FourF ₉) 26g
Put in. While sufficiently stirring this mixture, the reaction temperature was raised to 65 ° C.
The copolymerization reaction is performed while maintaining the temperature. Copolymerization reaction in progress
Is tetrafluoroethylene / ethylene / perful in the system
Orobutyl ethylene with a molar ratio of 53 / 46.3 / 0.7
A mixed gas was introduced, and the polymerization pressure was increased to 15.0 kg / cm.^TwoTo
Hold. After 5 hours, 460 g of a white copolymer was obtained.
The copolymer is C_TwoF_Four/ C_TwoH_Four/ CH_Two= CHC_Four
F₉Is 53 / 46.3 / 0.7,
The flow start temperature was 267 ° C and the thermal decomposition start temperature was 360 ° C.
Was.

The ethylene-tetrafluoroethylene copolymer obtained above is extruded at a resin temperature of 320 ° C.
A film having a thickness of 100 μm was produced (film X).
Next, one surface of the obtained film X is subjected to a corona treatment to obtain a wetting index (based on JIS-K6768) of 36 dyn.
/ Cm film. Further, an ethylene-tetrafluoroethylene copolymer film having a monomer composition shown in Table 1 and a corona-treated film Y having a thickness of 100 μm were prepared by the method of the above Production Example or a method analogous thereto.
And Z were obtained.

[0032]

[Table 1]

(2) Preparation of antifogging coating film Preparation of component (A) 80 g of isopropanol was charged into a 300 ml four-necked kolben, heated to 80 ° C. while stirring, and the components of the kind and amount shown in Table 2 were blended. The resulting mixed solution was added dropwise over 3 hours. After reacting at the same temperature for 2 hours after dropping,
0.3 g of AIVN was added, and the mixture was further reacted for 2 hours. Thus, a copolymer of a 50% IPA solution was obtained. Further, an acid is added to the solution and mixed well, and then 250 g of water is gradually added to obtain an aqueous dispersion. This aqueous dispersion was topped with IPA at a temperature of 50 ° C. or less under reduced pressure, and finally prepared with water to obtain a copolymer of the present invention (Resins A to E) having a solid content of 30%.

[0034]

[Table 2] The symbols in Table 2 mean the following, respectively. MP silane: γ-methacryloxypropyltrimethoxysilane AI: 1,1-dimethyl-1- (2-hydroxypropyl) amine methacrylimide HEA: 2-hydroxyethyl acrylate AA: acrylic acid MMA: methyl methacrylate BA: acrylic N-butyl acid BMA: n-butyl methacrylate LM: n-lauryl mercaptan AIVN: azobisisovaleronitrile

Preparation of antifogging agent composition The inorganic colloid sol and the hindered amine compound are mixed with the products (resin (a) to (e)) obtained in the above (3) in the types and ratios shown in Table 3 to prepare an antifogging agent composition. did. The liquid dispersion medium used was water and ethyl alcohol at a ratio of 3: 1. Formation of Antifogging Coating Film The obtained antifogging agent composition was coated on the corona-treated surface of the film by a bar coating method so that the coating amount after drying was 0.5 g / m ² as a solid content. The solution was applied and kept in hot air at 90 ° C. for 1 minute to disperse the solvent.

(3) Evaluation of antifogging agent composition The performance of the obtained antifogging agent composition was evaluated by the following method, and the results are shown in Table 3. Storage stability After the obtained antifogging agent composition was left in an oven at 50 ° C. for one month, the antifogging agent composition was taken out, and the appearance was visually observed. The evaluation criteria are as follows. ： １: The appearance does not change even if left for one month or more. Δ: Solids separated and settled slightly within one month after standing, but redispersed when shaken vigorously. ×: Solids aggregate and gel immediately after standing.

[0037]

[Table 3]

The notes in Table 3 mean the following, respectively. * 1 Parts by weight: Indicates the amount of polymer solids in the aqueous emulsion. * 3 Type: α; Tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) -1,2,3,4-butanetetracarboxylate (parts by weight): indicates the amount of solids.

(4) Evaluation of Film The performance of the obtained film was evaluated by the following method, and the results are shown in Table-4. Transparency Immediately after the formation of the coating film (initial stage) and at the time of each elongation, the appearance of the film was visually observed. The evaluation criteria are as follows. : Transparency almost equal to that of film X (uncoated film). ×: 〃 A slight decrease in transparency was observed. Δ: も の A considerable decrease in transparency was observed. ×: も の Transparency is extremely severe and is not practical.

Adhesion A cellophane tape was adhered to the surface on which the coating film was formed, and when the cellophane tape was peeled off, the peeling state of the coating film was visually observed. The evaluation criteria are as follows. ：: The coating film did not peel at all and remained completely. ×: A film in which 2/3 or more of the coating film remained without peeling. B: 2/3 or more of the coating film was peeled. X: The coating film was completely peeled off.

Antifogging property In a field in Isshi-gun, Mie, a frontage of 8.3 m, a depth of 12 m,
Each of the obtained films was coated on a roof-type house having a ridge height of 3.5 m and a roof inclination of 20 degrees such that the surface on which the anti-fog coating film was formed was located inside the house, and a stretching test was performed. The evaluation method is based on the situation where water droplets adhere to the film surface inside the house.
Observed visually over time. The evaluation criteria are as follows. ◎: Water adhered in a thin film state and no water droplets were observed. ：: Water is attached in a thin film form, but slightly large water droplets are observed. ×: A state in which water adheres in a thin film form, but adhesion of large water droplets is partially observed. Δ: A state in which fine water droplets are partially adhered. ×: A state in which fine water droplets are adhered over the entire surface.

[0042]

[Table 4]

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Keiko Iwase 2 Oike, Iwatsuka-cho, Nakamura-ku, Nagoya-shi, Aichi Prefecture Mitsubishi Chemical MKV Corporation Nagoya Office

Claims (6)

[Claims] 1. A coating film derived from an antifogging agent composition comprising the following three components (A), (B) and (C) as main components is formed on one or both surfaces of a fluororesin film. An agricultural fluororesin film characterized in that: (A) Vinyl copolymer comprising the following (a-1) to (a-5) (a-1) Vinyl monomer having hydrolyzable silyl group and / or hydrolyzable silyl group and vinyl group (A-2) Vinyl monomer having an amine imide group (a-3) Vinyl monomer having a hydroxyl group (a-4) Vinyl monomer having an ionic group or an ion-forming group ( a-5) (Meth) acrylic acid alkyl ester (alkyl group having 1 to 5 carbon atoms) (B) inorganic colloid sol (C) water and / or water-soluble solvent 2. The fluororesin film according to claim 1, wherein the fluororesin film is an ethylene-tetrafluoroethylene copolymer obtained by copolymerizing ethylene and tetrafluoroethylene at a ratio of 40/60 to 60/40 (molar ratio). Agricultural fluorine resin film. 3. The content of each structural unit in the vinyl copolymer of the component (A) is (a-1) 0.5 to 50%;
2) 0.5 to 50%, (a-3) 1 to 40%, (a-
4) 0.5 to 30%, (a-5) 30 to 90% (however,
The agricultural fluororesin film according to claim 1 or 2, wherein the total is 100). 4. The composition according to claim 1, wherein the amount of the component (B) is from 0.5 to 15 relative to the component (A) in terms of solids weight ratio. Agricultural fluorine resin film. 5. The agricultural fluororesin film according to claim 1, wherein the component (B) is a silica sol and / or an alumina sol. 6. The coating film according to claim 1, wherein the coating film contains a hindered amine compound containing at least one structural unit represented by the following general formula (I) in one molecule. The fluororesin film for agriculture according to the above item. Embedded image (Wherein, R ^{1 to} R ⁴ represent an alkyl group having 1 to ⁴ carbon atoms;
⁵ is hydrogen or an alkyl group having 1 to 4 carbon atoms, and
Each represents an alkyl ester group. )