JPH0690627A - Agricultural covering material - Google Patents

Abstract

PURPOSE:To obtain an agricultural covering material usable for any crops, stretchable for a long period of time, different from a conventional fluororesin- based covering material. CONSTITUTION:An agricultural covering material consists of a fluororesin-based film substantially preventing transmission of light rays at least in an ultraviolet light range and not substantially checking transmission of light rays in a visible light range.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an agricultural coating material,
More specifically, the present invention relates to a covering material for agriculture which is capable of being extended for a long period of time and which partially shields light in a specific wavelength range.

[0002]

2. Description of the Related Art Conventionally, polyethylene film, ethylene-vinyl acetate copolymer film, polyester film, vinyl chloride resin film, etc. have been used as coating materials for tunnels and pipe houses, but vinyl chloride resin film has been applied. It occupies the most in terms of sex, price and heat retention. However, since these resins have poor outdoor durability, the coating period is 1 to 2 years, and the farmer refills the coating material each time.

On the other hand, in recent years, full-scale large-scale houses have been adopted for the purpose of labor saving of house management, expansion of cultivation area, extension of house life, and the like. For this large-scale house, covering materials such as polyester resin plate, polycarbonate resin plate, hard vinyl chloride resin plate, acrylic resin plate, fiber reinforced plastic plate, and plate glass are used for long-term expansion for more than 5 years. However, since these coating materials have a large thickness, they must be spread using large-sized dedicated substrates,
There is a drawback that the workability is very complicated and relatively expensive. Further, polyester resin plate, polycarbonate resin plate, hard vinyl chloride resin plate, acrylic resin plate and the like have a drawback that cracks are easily generated due to hail, etc., and the generated cracks are easily propagated. , Easy to break,
Once broken, it can't remove fine glass pieces,
I had to replace the soil in the house.

Furthermore, in addition to the pests that have inhabited Japan in the past, such as aphids, spider mites, and Thrips palmi, for example, the pests that have newly invaded in recent years from overseas, such as Thrips palmi thrips and bean, are cultivated crops. Various pests such as leaf flies are attached and inhabited. The ecology of these new pests is unknown, and conventional pesticides have no medicinal effect, and farmers have been struggling to take measures against them.

In order to solve these problems, coating materials made of fluororesin have been proposed. However, these materials transmit light rays in all wavelength regions of sunlight, and therefore, depending on crops. , There was some harm. For example, when it was used in a house for red-colored rose cultivation, the reddish color sometimes became black red. Furthermore, the outbreak of the above-mentioned pests could not be prevented.

Therefore, recently, from the viewpoint of economical efficiency, labor saving, diversification of demand, etc., it is excellent in durability, dustproofness, partly blocking light in a specific wavelength range, and also excellent in visible light transmittance, etc. It can be spread, can be used universally for various crops without any restrictions, and also has insect repellency, and is easy to install even on a full-scale large-scale house and can be installed relatively inexpensively. The development of coating materials that can be done is strongly desired.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems that conventional agricultural coating materials have, and a completely new agriculture that has not been known until now. The purpose is to provide a coating material for use.

[0008]

The present invention has been made to solve the above-mentioned problems, and is at least 300 to 3
Substantially blocks transmission of light in the wavelength range of 30 nm, and 4
It is an object of the present invention to provide an agricultural coating material comprising a fluororesin film which substantially transmits light in the wavelength range of 00 to 800 nm.

Thus, according to the present invention, it is possible to obtain an agricultural coating material which can be used for any agricultural products and can be extended for a long period of time. Hereinafter, the constituent factors of the present invention will be described in more detail.

The "fluororesin" used in the agricultural coating material of the present invention is a general term for synthetic resins obtained by polymerization of olefin containing fluorine, and in the present invention, the fluorine content is generally 35% by weight. As described above, further 40% by weight or more, particularly 55% by weight or more are preferably used. Examples of such fluororesin include ethylene-
Tetrafluoroethylene-based copolymer, ethylene-chlorotrifluoroethylene-based copolymer, hexafluoropropylene-tetrafluoroethylene-based copolymer, per-fluoroalkyl vinyl ether-tetrafluoroethylene-based copolymer, polyfluorination Examples thereof include vinylidene and polyvinyl fluoride, and any of these can be used in the present invention, but among them, an ethylene-tetrafluoroethylene-based copolymer is preferable.

The ethylene-tetrafluoroethylene copolymer is mainly composed of ethylene and tetrafluoroethylene (the molar ratio of ethylene / tetrafluoroethylene is generally 40/60 to 60/40), and if necessary, It is a copolymer of a small amount (usually 10 mol% or less) of the third comonomer component.
Ethylene / tetrafluoroethylene content molar ratio is 40
/ 60 to 60/40, preferably 45/55 to 55/4
In the range of 5, and the formula _{CH 2 = CH-C n F} 2n + 1 ( where, n is an integer of 2 to 10) Pas represented by - fluoroalkyl vinyl monomer - units (e.g., CH ₂ = C
H-C ₄ H ₉ or CH ₂ = content of units) derived from CH-C ₆ H ₁₃ 0.1 to 10 mol%, preferably 0.3
An ethylene-tetrafluoroethylene copolymer in the range of 5 mol% is preferably used. This ethylene
The tetrafluoroethylene-based copolymer is known per se and can be produced, for example, by the method described in JP-B-59-50163, and is commercially available from Asahi Glass Co., Ltd. under the name "Aflon COP". It is also possible to use a commercially available product under the trade name.

The film formation from the above-mentioned fluororesin is carried out according to a method known per se, for example, an extrusion molding method,
It can be performed by an inflation molding method or the like.

The agricultural coating material used in the present invention has a light transmittance in the wavelength region of at least 300 to 330 nm of 50 to 85%, preferably 60 to 83%, more preferably 70 to 80%. And the light transmittance in the wavelength range of 400 nm and above is 70% or more, preferably 80
% Or more, and more preferably 85% or more.

In the present specification, the term "substantially block the transmittance of light rays in the wavelength range of 300 to 330 nm" means:
Not only in the case of completely blocking the transmission of light in the wavelength range of 300 to 330 nm, the transmission of light in the wavelength range of 300 to 330 nm is at least 50% or more, preferably 70% or more, more preferably 80% or more, Particularly preferably 90
It is used for the purpose of including the case of shielding by more than%.

The term "substantially transmits light in the wavelength range of 400 to 800 nm" means not only the case of completely transmitting the light in the wavelength range of 400 to 800 nm, but also 400 to 800 nm.
It is intended to include the case of transmitting at least 70% or more, preferably 80% or more, more preferably 85% or more, particularly preferably 88% or more of light in the wavelength region of 800 nm.

For this purpose, in particular 300-330 nm
Substantially blocks the transmission of light in the wavelength range of
A substance having a property of substantially transmitting a light ray in the wavelength range of 800 nm (hereinafter referred to as "substance A") is mixed with the above fluororesin to form a film, or a method of applying it to the film surface after the film formation, etc. There is.

The substance A is not particularly limited and may be any substance as long as it has the above characteristics. These substances include inorganic compounds, organic compounds and mixtures thereof.

Examples of the inorganic compound include titanium oxide (TiO ₂ ), zinc oxide (ZnO), mica, alumina (Al
₂ O ₃ ), colloidal silica (SiO ₂ ), iron oxide (Fe ₂ O ₃ ), etc., among which TiO ₂ and ZnO are preferable. The particle size of these inorganic compounds is not particularly limited and may be any particle size, for example, 1 μm or less, preferably 0.5 μm
Especially preferably, it is 0.3 μm or less, more preferably 0.3 μm.
It is 2 μm or less, particularly preferably 0.1 μm or less.

The amount of these inorganic compounds blended in the film varies depending on the resin used and the film thickness, but is generally 0.01 to 10% by weight, preferably 0.1 to 10% by weight. It is 5% by weight, more preferably 0.3 to 1% by weight.

Further, as the organic compound which can be the substance A, there are, for example, an ultraviolet absorber, a light stabilizer and an antioxidant, and among them, the ultraviolet absorber is preferably used.

The ultraviolet absorber which can be blended with these synthetic resins is appropriately selected from a wide range of types in consideration of the ultraviolet absorbing ability of the ultraviolet absorber and compatibility with the synthetic resin used. You can Examples of usable ultraviolet absorbers include the followings.

Hydroquinone hydroquinone, hydroquinone disalicylate salicylate phenyl salicylate, paraoctyl phenyl salicylate

Benzophenone type 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, 2-hydroxy-4-methoxy-2'-carboxybenzophenone, 2,4- Hydroxybenzophenone, 2,2'-
Hydroxy-4,4'-dimethoxybenzophenone, 2
-Hydroxy-4-benzoyloxybenzophenone,
2,2'-hydroxy-4-methoxybenzophenone,
2-hydroxy-4-methoxy-5-sulfonebenzophenone, 2,2 ', 4,4'-tetrahydroxybenzophenone, 2,2'-hydroxy-4,4'-dimethoxy-5-sodium sulfobenzo Phenone, 4-dotesiloxy-2-hydroxybenzophenone, 2-hydroxy-5-chlorobenzophenone

Benzotriazole type 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-5'-methylphenyl) -5-carboxylic acid butyl ester benzotriazole, 2- (2'-hydroxy-5'-methylphenyl) -5,6-dichlorobenzotriazole, 2-
(2'-Hydroxy-5'-methylphenyl) -5-ethylsulfone benzotriazole, 2- (2'-hydroxy-5'-tert-butylphenyl) -5-chlorobenzotriazol, 2- ( 2'-hydroxy-5'-tertiary butylphenyl) benzotriazole, 2- (2'-hydroxy-5'-amylphenyl) benzotriazole,
2- (2'-hydroxy-3 ', 5'-dimethylphenyl) benzotriazole, 2- (2'-hydroxy-3)
′, 5′-Dimethylphenyl) -5-methoxybenzotriazole, 2- (2′-methyl-4′-hydroxyphenyl) benzotriazole, 2- (2′-stearyloxy-3 ′, 5'-Dimethylphenyl) -5-methylbenzotriazole

2- (2'-hydroxy-5-carboxylic acid phenyl) benzotriazol ethyl ester, 2-
(2'-hydroxy-3'-methyl-5'-tertiary butylphenyl) benzotriazole, 2- (2'-hydroxy-3 ', 5'-ditertiary butylphenyl) -5-chloro-benzotriazole, 2- (2'-hydroxy-5 '
-Methoxyphenyl) benzotriazole, 2- (2 '
-Hydroxy-5'-phenylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-5'-
Cyclohexylphenyl) benzotriazole, 2-
(2'-hydroxy-4 ', 5'-dimethylphenyl)
-5-carboxylic acid benzotriazol butyl ester

2- (2'-hydroxy-3 ', 5'-dichlorophenyl) benzotriazole, 2- (2'-hydroxy-4', 5'-dichloro) benzotriazo-
2- (2'-hydroxy-3 ', 5'-dimethylphenyl) -5-ethylsulfone benzotriazole, 2
-(2'-hydroxy-5'-phenylphenyl) benzotriazole, 2- (2'-hydroxy-4'-octoxyphenyl) benzotriazole, 2- (2'-hydroxy-5'-methoxyphenyl) ) -5-Methylbenzotriazol, 2- (2'-hydroxy-5'-methylphenyl) -5-carboxylic acid ester benzotriazol, 2- (2'-acetoxy-5'-methylphenyl) benzotriazo -L, 2- (2'-hydroxy-3
′, 5′-Di-sialybutylphenyl) -5-chlorobenzotriazol.

Of these ultraviolet absorbers, those of benzophenone type and benzotriazole type are preferable,
Among them, in benzophenone series, 2,3'-dihydroxy-
4,4'-dimethoxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone and 2,2 ',
4,4'-Tetrahydroxybenzophenone: 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-5-methylphenyl) -5,6-in the benzotriazol system Dichlorobenzotriazole, 2- (2-hydroxy-5'-tert-butylphenyl) benzotriazole,

2- (2'-hydroxy-3'-methyl-
5'-tert-butylphenyl) benzotriazole, 2-
(2'-Hydroxy-3 ', 5' ditertiary butylphenyl) -5-chloro-benzotriazole and 2- (2 '
-Hydroxy-5'-phenylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3 ',
5'-Diter-shartylbutylphenyl) -5-chlorobenzotriazol, 2- (2'-hydroxy-5'-octoxyphenyl) benzotriazole and the like are effective.

When the substance A is blended with a resin to form a film, its function can be maintained for a long time, but the effect of the present invention can be easily obtained by applying it to the surface of the agricultural coating material. While this is not expected to have a long-term effect, it can be appropriately applied depending on the growing stage of the crop when treatment is required.

For example, in the cultivation of flowers and the like, the flower color is made brighter by processing before flowering, and in the cultivation of cucumber,
By treating before harvesting, it becomes possible to suppress the aging of the seedlings. The coating surface may be either the inner surface or the outer surface of the house or both surfaces, but the inner surface of the house is preferred.

As the coating method, the substance A may be mixed with a binder having an action of holding the substance A, and the mixture may be coated with a solvent by using, for example, a sprayer used by a farmer.

In order to industrially carry out the coating treatment, it is important to preliminarily subject the fluororesin film to the surface activation treatment. The surface activation treatment enables firm adhesion to the coating layer, and also prevents cissing of the solution when coating.

Examples of such surface activation treatment include corona discharge treatment, sputter etching treatment, sodium treatment, sandblast treatment and the like. In corona discharge treatment, discharge is performed between a needle-shaped or knife-edge electrode and a counter electrode, and a sample is placed between them to perform treatment, and aldehydes, acids, alcohol peroxides, ketones, ethers, etc. on the film surface are treated. This is a treatment for generating a functional group containing oxygen.

The sodium treatment is a treatment of immersing the film in a liquid ammonia solution of an alkali metal such as metallic sodium, in which CF ₂ bonds are eliminated from the surface and CH,
This is a process of generating a C-O bond. In the sputter etching treatment, a sample is put between electrodes under low pressure glow discharge, and a large number of fine projections are formed on the film by the impact of positive ions generated by the glow discharge.

The sandblast treatment is to spray fine sand on the film surface to form a large number of fine irregularities on the surface. Among these surface activation treatments, in terms of adhesion with the coating layer, workability, safety, cost, etc.,
It is preferable to perform corona discharge treatment.

The coating layer containing the substance A may be formed by coating the substance A itself to form the coating layer, or may be formed by coating a mixture of the substance A with a binder solution to form the coating layer.
In addition to the substance A, a surfactant, a hydrophilic polymer and a mixture of two or more of them may be added to the coating layer containing the substance A in the present invention.

Examples of such a surfactant include, for example,
Sorbitan fatty acid ester, sorbitol fatty acid ester, diglycerin fatty acid ester, glycerin fatty acid ester, sorbitan fatty acid dibasic acid ester, sorbitol fatty acid dibasic acid ester, diglycerin fatty acid dibasic acid ester, glycerin fatty acid dibasic acid ester and Examples thereof include compounds in which alkylene oxide such as ethylene oxide and propylene oxide is added.

Examples of the hydrophilic polymer include, in addition to polyvinyl alcohol, polyvinylpyrrolidone, etc., --SO ₄ , --SO ₃ H, --COOH, --CN,-(0
Polymers having hydrophilic functional groups such as CH ₂ CH ₂ ) are generally included.

Examples of the binder include (meth) acrylic acid ester resin and vinyl acetate resin. A solvent, an additive and the like may be added to the coating composition containing the substance A for the purpose of improving workability and surface smoothness. As the solvent, for example, water, various alcohols, ketones, esters, ethers and the like can be appropriately used.

The coating composition may be applied to a fluororesin film by brush coating, dip coating,
It is possible to use commonly known methods such as gravure coating and spray coating.

The amount of the substance A used here varies depending on the film thickness to be applied, the binder used, and the amount of other additives, but is 0.5 to 95% by weight in the dry coating film. Preferably 1 to 50% by weight, more preferably 3 to
It is 30% by weight.

The film thus obtained is a covering material for agriculture which can be used for any agricultural crop and can be extended for a long period of time, and for example, it can be spread on roses to prevent black discoloration of flower color. In addition, in the crops such as cucumber in which aging significantly appears, aging can be reduced and it contributes to the industry, which is extremely large.

Hereinafter, the present invention will be described in more detail by way of examples, but it goes without saying that the present invention is not limited to the examples.

[0043]

【Example】

 Comparative Example 1 An autoclave having an internal volume of 10 liters was charged with trichloromonophene.
Luoromethane 3.46 kg, trichlorotrifluoroethane
6.52 kg, and t-butylperoxyisobutyrate
2.38 g of gut was charged, and then futrafluoroethylene 1
226 g, ethylene 82 g, and perfluorobutyl ethyl
Ren (CH₂= CH-C_FourF₉) Charge 26g. This mix
Keep the reaction temperature at 65 ° C while stirring
Allow the polymerization reaction to occur. While the copolymerization reaction is in progress,
Lafluoroethylene / ethylene / perfluorobutylene
Introduce a mixed gas with a molar ratio of thylene of 53 / 46.3 / 0.7
And the polymerization pressure is 15.0 kg / cm²Hold on. After 5 hours
460 g of white copolymer was obtained (hereinafter referred to as resin No. 1)
Say). The copolymer is C₂F_Four/ C₂H_Four/ CH₂ = CH
C_FourF₉Has a molar ratio of 53 / 46.3 / 0.7,
The flow starting temperature is 267 ° C and the thermal decomposition starting temperature is 360 ° C.
It was

The ethylene-tetrafluoroethylene copolymer (hereinafter sometimes abbreviated as "ETFE") obtained above was extruded at a resin temperature of 320 ° C. to produce a film having a thickness of 60 μm. The obtained film was used as coating material No. 1 and subjected to various tests, and the results are summarized in Table 1 below.

Examples 1 to 4 Resin No. 1 prepared in Comparative Example 1 had 0.1 μm as shown in Table 1.
except that the addition of TiO ₂ and ZnO of m, covering material N
The coating material was prepared in the same manner as in o.1.

Example 5 One surface of coating material No. 1 prepared in Comparative Example 1 was applied with a discharge current of 10 A, a discharge voltage of 120 V and a line speed of 13 m / min.
The corona discharge treatment was performed under the conditions. On the treated surface, silica sol (silica solid content 8%) to which polyvinyl alcohol 5 wt% and TiO ₂ 5 wt% were added was treated with ethanol.
The coating material was obtained by diluting it 0 times and coating it so as to be 15 g / m ² (coating material No. 6).

Reference Example 1 Using the covering materials Nos. 1 to 6 obtained in the examples, the house was partitioned at a depth of 50 m in a house with a frontage of 10 m and a depth of 100 m, and one was separated into roses (variety: curl red). ) And cucumber (cultivar: Sharp 1) were cultivated, and the flower color of rose, the senescence of cucumber and the habitation of pests were examined, and the results are shown in Table 2.

The degree of pest habitation is indicated as follows. ◎ ... Almost no pests are found. ○: A few pests were seen, but there was no actual damage. △: Pests were seen.

[0049]

[Table 1]

[0050]

[Table 2]

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] September 9, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Claims

[Correction method] Change

[Correction content]

[Claims]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be amended] Detailed explanation of the invention

[Correction method] Change

[Correction content]

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an agricultural coating material,
More specifically, the present invention relates to a covering material for agriculture which is capable of being extended for a long period of time and which partially shields light in a specific wavelength range.

[0002]

2. Description of the Related Art Conventionally, polyethylene film, ethylene-vinyl acetate copolymer film, polyester film, vinyl chloride resin film, etc. have been used as coating materials for tunnels and pipe houses, but vinyl chloride resin film has been applied. It occupies the most in terms of sex, price and heat retention. However, since these resins have poor outdoor durability, the coating period is 1 to 2 years, and the farmer refills the coating material each time.

On the other hand, in recent years, full-scale large-scale houses have been adopted for the purpose of labor saving of house management, expansion of cultivation area, extension of house life, and the like. For this long-term house, a covering material such as a polyester resin plate, a polycarbonate resin plate, a hard vinyl chloride resin plate, an acrylic resin plate, a fiber reinforced plastic plate, and plate glass is used for long-term extension for more than 5 years. Since these covering materials have a large thickness, they must be spread using a large dedicated substrate,
There is a drawback that the workability is very complicated and relatively expensive. Further, polyester resin plate, polycarbonate resin plate, hard vinyl chloride resin plate, acrylic resin plate and the like have a drawback that cracks easily occur due to hail, etc., and the cracks that occur easily propagate, and plate glass is easily damaged. ,
Once broken, it can't remove fine glass pieces,
I had to replace the soil in the house.

Furthermore, in addition to the pests that have inhabited Japan in the past, such as aphids, spider mites, and Thrips palmi, for example, the pests that have newly invaded in recent years from overseas, such as Thrips palmi thrips and bean, are cultivated crops. Various pests such as leaf flies are attached and inhabited. The ecology of these new pests is unknown, and conventional pesticides have no medicinal effect, and farmers have been struggling to take measures against them.

In order to solve these problems, coating materials made of fluororesin have been proposed. However, these materials transmit light rays in all wavelength regions of sunlight, and therefore, depending on crops. , There was some harm. For example, when it was used in a house for red-colored rose cultivation, the reddish color sometimes became black red. Furthermore, the outbreak of the above-mentioned pests could not be prevented.

Therefore, recently, from the viewpoint of economical efficiency, labor saving, diversification of demand, etc., it is excellent in durability, dustproofness, partly blocking light in a specific wavelength range, and also excellent in visible light transmittance, etc. It can be spread, can be used universally for various crops without any restrictions, and also has insect repellency, and is easy to install even on a full-scale large-scale house and can be installed relatively inexpensively. The development of coating materials that can be done is strongly desired.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems that conventional agricultural coating materials have, and a completely new agriculture that has not been known until now. The purpose is to provide a coating material for use.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and substantially blocks the transmission of light rays in at least the ultraviolet region and substantially transmits the light rays in the visible light region. It is an object of the present invention to provide a covering material for agriculture, which is characterized by comprising a fluororesin film that does not physically block.

Thus, according to the present invention, it is possible to obtain an agricultural coating material which can be used for any agricultural products and can be extended for a long period of time. Hereinafter, the constituent factors of the present invention will be described in more detail.

The "fluororesin" used in the agricultural coating material of the present invention is a general term for synthetic resins obtained by polymerization of olefin containing fluorine, and in the present invention, the fluorine content is generally 35% by weight. As described above, further 40% by weight or more, particularly 55% by weight or more are preferably used. Examples of such fluororesin include ethylene-
Tetrafluoroethylene-based copolymer, ethylene-chlorotrifluoroethylene-based copolymer, hexafluoropropylene-tetrafluoroethylene-based copolymer, perfluoroalkyl vinyl ether-tetrafluoroethylene-based copolymer, polyvinylidene fluoride, polyfluoride In the present invention, any of these may be used, and among them, ethylene-tetrafluoroethylene-based copolymers are preferable.

The ethylene-tetrafluoroethylene copolymer is mainly composed of ethylene and tetrafluoroethylene (the molar ratio of ethylene / tetrafluoroethylene is generally 40/60 to 60/40), and if necessary, A small amount (usually 10 mol% or less) of a third comonomer component is copolymerized, and in the present invention, in particular,
Ethylene / tetrafluoroethylene content molar ratio is 40
/ 60 to 60/40, preferably 45/55 to 55/4
In the range of 5, and the formula _CH 2 = _CH-C n F
_{2n + 1} (where n is an integer of 2 to 10) represented by a perfluoroalkylville monomer unit (for example,
_{CH 2 = CH-C 4 H} 9 or _CH 2 = _CH-C 6 H
_An ethylene-tetrafluoroethylene-based copolymer having a content of (unit derived from ₁₃ ) in the range of 0.1 to 10 mol%, preferably 0.3 to 5 mol% is suitably used. This ethylene-tetrafluoroethylene copolymer is known per se, for example, Japanese Patent Publication No. 59-5.
It can be produced by the method described in JP-A No. 0163, and is commercially available from Asahi Glass Co.
It is also possible to use a commercially available product under the trade name P).

The film formation from the above-mentioned fluororesin is carried out according to a method known per se, for example, an extrusion molding method,
It can be performed by an inflation molding method or the like.

In the present specification, the term "substantially block the transmittance of light rays in the ultraviolet region" means not only the case of completely blocking the transmission of light rays in the ultraviolet region but also the case of the light rays in the ultraviolet region. It is intended to include the case where transmission is blocked by at least 50% or more, preferably 70% or more, more preferably 80% or more, and particularly preferably 90% or more.

The term "does not substantially block transmission of light in the visible light region" means not only the case of completely transmitting light in the visible light region, but also the light in the visible light region of at least 70% or more, It is preferably used in the sense of including 80% or more, more preferably 85% or more, and particularly preferably 88% or more.

For this purpose, in particular, a substance having characteristics of substantially blocking transmission of light rays in the ultraviolet region and substantially transmitting light rays in the wavelength region of the visible light region (hereinafter referred to as "substance A"). ") Is mixed with the above-mentioned fluororesin to form a film, or a method of applying it to the film surface after forming the film.

The substance A is not particularly limited and may be any substance as long as it has the above characteristics. These substances include inorganic compounds, organic compounds and mixtures thereof.

Examples of the inorganic compound include titanium oxide (TiO ₂ ), zinc oxide (ZnO), mica, alumina (Al ₂ O ₃ ), colloidal silica (SiO ₂ ), iron oxide (Fe ₂ O ₃ ), and the like. Of these, TiO ₂ and ZnO are preferable. The particle size of these inorganic compounds is not particularly limited and may be any particle size, for example, 1 μm.
Or less, preferably 0.5 μm or less, particularly preferably 0.3
It is not more than μm, more preferably not more than 0.2 μm, particularly preferably not more than 0.1 μm.

The blending amount of these inorganic compounds in the film varies depending on the resin used and the film thickness, but is generally 0.01 to 10% by weight, preferably 0.1 to 10% by weight. 5% by weight, more preferably 0.3 to 1
% By weight.

Further, as the organic compound which can be the substance A, there are, for example, an ultraviolet absorber, a light stabilizer and an antioxidant, and among them, the ultraviolet absorber is preferably used.

The ultraviolet absorber which can be blended with these synthetic resins is appropriately selected from a wide range of types in consideration of the ultraviolet absorbing ability of the ultraviolet absorber and compatibility with the synthetic resin used. You can Examples of usable ultraviolet absorbers include the followings.

Hydroquinone hydroquinone, hydroquinone disalicylate salicylate phenyl salicylate, paraoctyl phenyl salicylate

Benzophenone type 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, 2-hydroxy-4-methoxy-2'-carboxybenzophenone, 2,4- Hydroxybenzophenone, 2,2'-
Hydroxy-4,4'-dimethoxybenzophenone, 2
-Hydroxy-4-benzoyloxybenzophenone,
2,2'-hydroxy-4-methoxybenzophenone,
2-Hydroxy-4-methoxy-5-sulfonebenzophenone, 2,2 ', 4,4'-tetrahydroxybenzophenone, 2,2'-hydroxy-4,4'-dimethoxy-5-sodium sulfobenzo Phenone, 4-dotesiloxy-2-hydroxybenzophenone, 2-hydroxy-5-chlorobenzophenone

Benzotriazole type 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-5'-methylphenyl) -5-carboxylic acid butyl ester benzotriazole, 2- (2 '-Hydroxy-5'-methylphenyl) -5,6-dichlorobenzotriazole, 2-
(2'-Hydroxy-5'-methylphenyl) -5-ethylsulfone benzotriazole, 2- (2'-hydroxy-5'-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-5) ′ -Tert-Butylphenyl) benzotriazole, 2- (2′-hydroxy-5′-amylphenyl) benzotriazole,
2- (2'-hydroxy-3 ', 5'-dimethylphenyl) benzotriazole, 2- (2'-hydroxy-
3 ', 5'-Dimethylphenyl) -5-methoxybenzotriazole, 2- (2'-methyl-4'-hydroxyphenyl) benzotriazole, 2- (2'-stearyloxy-3', 5'- Dimethylphenyl) -5-methylbenzotriazole

2- (2'-hydroxy-5-carboxylic acid phenyl) benzotriazole ethyl ester, 2-
(2'-Hydroxy-3'-methyl-5'-tert-butylphenyl) benzotriazole, 2- (2'-hydroxy-3 ', 5'-di-tert-butylphenyl) -5-chloro-benzotriazole, 2- (2'-hydroxy-5 '
-Methoxyphenyl) benzotriazole, 2- (2 '
-Hydroxy-5'-phenylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-5'-
Cyclohexylphenyl) benzotriazole, 2-
(2'-hydroxy-4 ', 5'-dimethylphenyl)
-5-carboxylic acid benzotriazole butyl ester

2- (2'-hydroxy-3 ', 5'-dichlorophenyl) benzotriazole, 2- (2'-hydroxy-4', 5'-dichloro) benzotriazole, 2- (2'-hydroxy-3) ′, 5′-Dimethylphenyl) -5-ethylsulfone benzotriazole, 2
-(2'-hydroxy-5'-phenylphenyl) benzotriazole, 2- (2'-hydroxy-4'-octoxyphenyl) benzotriazole, 2- (2'-hydroxy-5'-methoxyphenyl)- 5-methylbenzotriazole, 2- (2'-hydroxy-5'-methylphenyl) -5-carboxylic acid ester benzotriazole, 2- (2'-acetoxy-5'-methylphenyl) benzotriazole, 2- (2'- Hydroxy-
3 ', 5'-Di-sialybutylphenyl) -5-chlorobenzotriazole.

Of these ultraviolet absorbers, those of benzophenone type and benzotriazole type are preferable,
Among the benzophenone-based compounds, 2,3'-dihydroxy-
4,4'-dimethoxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone and 2,2 ',
4,4'-Tetrahydroxybenzophenone: 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-5-methylphenyl) -5,6-dichloro in the benzotriazole system Benzotriazole, 2- (2-hydroxy-5'-tert-butylphenyl) benzotriazole,

2- (2'-hydroxy-3'-methyl-
5'-tert-butylphenyl) benzotriazole, 2-
(2'-Hydroxy-3 ', 5' ditertiary butylphenyl) -5-chloro-benzotriazole and 2- (2 '
-Hydroxy-5'-phenylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3 ',
5'-Diter-shaributylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-5'-octoxyphenyl) benzotriazole and the like are effective.

When the substance A is blended with a resin to form a film, its function can be maintained for a long time, but the effect of the present invention can be easily obtained by applying it to the surface of the agricultural coating material. While this is not expected to have a long-term effect, it can be appropriately applied depending on the growing stage of the crop when treatment is required.

For example, in the cultivation of flowers and the like, the flower color is made brighter by processing before flowering, and in the cultivation of cucumber,
By treating before harvesting, it becomes possible to suppress the aging of the seedlings. The coating surface may be either the inner surface or the outer surface of the house or both surfaces, but the inner surface of the house is preferred.

As a coating method, the above substance A may be mixed with a binder having an action of holding the substance A, and this may be coated with a solvent by using, for example, a sprayer used by a farmer.

In order to industrially carry out the coating treatment, it is important to preliminarily subject the fluororesin film to the surface activation treatment. The surface activation treatment enables firm adhesion to the coating layer, and also prevents cissing of the solution when coating.

Examples of such surface activation treatment include corona discharge treatment, sputter etching treatment, sodium treatment, sandblast treatment and the like. In corona discharge treatment, a discharge is performed between a needle-shaped or knife-edge electrode and a counter electrode, and a sample is placed between them to perform treatment, and a functional group containing oxygen such as aldehyde, acid, alcohol peroxide, ketone, and ether on the film surface. This is a process for generating a group.

The sodium treatment is a treatment of immersing the film in a liquid ammonia solution of an alkali metal such as metallic sodium, which eliminates CF ₂ bonds from the surface, and CH,
This is a process of generating a C-O bond. In the sputter etching treatment, a sample is put between electrodes under low-pressure glow discharge, and a large number of fine projections are formed on the film by the impact of positive ions generated by the glow discharge.

The sandblast treatment is to spray fine sand on the film surface to form a large number of fine irregularities on the surface. Among these surface activation treatments, in terms of adhesion with the coating layer, workability, safety, cost, etc.,
It is preferable to perform corona discharge treatment.

The coating layer containing the substance A may be formed by coating the substance A itself to form the coating layer, or may be formed by coating a mixture of the substance A with a binder solution to form the coating layer.
In addition to the substance A, a surfactant, a hydrophilic polymer and a mixture of two or more of them may be added to the coating layer containing the substance A in the present invention.

Examples of such a surfactant include, for example,
Sorbitan fatty acid ester, sorbitol fatty acid ester, diglycerin fatty acid ester, glycerin fatty acid ester, sorbitan fatty acid dibasic acid ester, sorbitol fatty acid dibasic acid ester, diglycerin fatty acid dibasic acid ester, glycerin fatty acid dibasic acid ester and ethylene oxide , A compound to which an alkylene oxide such as propylene oxide is added, and the like.

As the hydrophilic polymer, for example, in addition to polyvinyl alcohol, polyvinylpyrrolidone, etc., --SO ₄ , --SO ₃ H, --COOH, --CN,-
Generally included are polymers having hydrophilic functional groups such as (O CH ₂ CH ₂ ).

Examples of the binder include (meth) acrylic acid ester resin and vinyl acetate resin. A solvent, an additive and the like may be added to the coating composition containing the substance A for the purpose of improving workability and surface smoothness. As the solvent, for example, water, various alcohols, ketones, esters, ethers and the like can be appropriately used.

The coating composition may be applied to a fluororesin film by brush coating, dip coating,
It is possible to use commonly known methods such as gravure coating and spray coating.

The amount of the substance A used here varies depending on the film thickness to be coated, the binder used, and the amount of other additives, but is 0.5 to 95% by weight in the dry coating film, preferably Is 1 to 50% by weight, more preferably 3 to
It is 30% by weight.

The film thus obtained is a covering material for agriculture which can be used for any agricultural crop and can be extended for a long period of time, and for example, it can be spread on roses to prevent black discoloration of flower color. In addition, in the crops such as cucumber in which aging significantly appears, aging can be reduced and it contributes to the industry, which is extremely large.

Hereinafter, the present invention will be described in more detail by way of examples, but it goes without saying that the present invention is not limited to the examples.

[0043]

Example Comparative Example 1 An autoclave having an internal volume of 10 liters was charged with 3.46 kg of trichloromonofluoromethane, 6.52 kg of trichlorotrifluoroethane, and 2.38 g of t-butylperoxyisobutyrate, and then futrafluoro. ethylene 1226G, ethylene 2g, and perfluorobutyl ethylene _{(CH 2 = CH-C 4} F 9) is charged with 26 g. While stirring the mixture well, the reaction temperature was adjusted to 65
The copolymerization reaction is carried out by keeping the temperature at ℃. During the progress of the copolymerization reaction, the molar ratio of tetrafluoroethylene / ethylene / perfluorobutylethylene was 53 / 46.3 / 0.7.
Of the mixed gas of 15.0 kg / cm ²
Hold on. After 5 hours, 460 g of a white copolymer was obtained (hereinafter referred to as resin No. 1). The copolymer is C
The content molar ratio of ₂ F ₄ / C ₂ H ₄ / CH ₂ = CHCF ₉ is 53 / 46.3 / 0.7, and the flow starting temperature is 26.
The temperature was 7 ° C and the thermal decomposition starting temperature was 360 ° C.

The ethylene-tetrafluoroethylene copolymer (hereinafter sometimes abbreviated as "ETFE") obtained above was extruded at a resin temperature of 320 ° C. to produce a film having a thickness of 60 μm. The obtained film was coated with coating material No. The results are shown in Table 1 below.

Examples 1 to 4 Resin Nos. Prepared in Comparative Example 1 1 shown in Table-1.
Other than the addition of 1 μm TiO ₂ and ZnO, coating material No. A coating material was prepared in the same manner as in 1.

Example 5 Coating material No. prepared in Comparative Example 1 1 side, discharge current 10A, discharge voltage 120V, line speed 13m /
Corona discharge treatment was performed under the condition of min. Polyvinyl alcohol 5 on silica sol (silica solid content 8%) on treated surface
The coating material was obtained by diluting 100% by weight with ethanol to which 5% by weight of TiO _{2 and} 5% by weight of TiO ₂ were added, and coating it so as to be 15 g / m ² (coating material No. 6).

Reference Example 1 Coating material No. obtained in the example. Using 1 to 6,
A house with a frontage of 10 m and a depth of 100 m is partitioned at a depth of 50 m, and roses (cultivar: curl red) and cucumber (cultivar: sharp 1) are cultivated on one side, rose flower color, cucumber aging and pest habitat. The degree was examined, and the results are shown in Table 2.

The degree of pest habitation is indicated as follows. ◎ ... Almost no pests are found. ○: A few pests were seen, but there was no actual damage. △: Pests were seen.

[0049]

[Table 1]

[0050]

[Table 2]

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Internal reference number FI Technical indication location C08K 3/22 7242-4J C08L 27/18 KJG 9166-4J (72) Inventor Yasuharu Wakusaki Toyama Prefecture 391 Yamada Arata, Kurobe

Claims (7)

[Claims] 1. An agriculture comprising a fluororesin film which substantially blocks transmission of light in the wavelength range of at least 300 to 330 nm and substantially transmits light in the wavelength range of 400 to 800 nm. Covering material. 2. The covering material for agriculture according to claim 1, wherein the substance having the blocking function is TiO ₂ . 3. The compounding amount of TiO ₂ is 0.01 to 10% by weight.
The covering material for agriculture according to claim 2. 4. The covering material for agriculture according to claim 1, wherein the fluorine content of the fluororesin is 40% by weight or more. 5. The fluororesin film is ethylene-based.
Tetrafluoroethylene-based copolymer, ethylene-chlorotrifluoroethylene-based copolymer, hexafluoropropylene-tetrafluoroethylene-based copolymer, per-fluoroalkyl vinyl ether-tetrafluoroethylene-based copolymer, polyfluorination The agricultural coating material according to claim 1, which is a film formed of a resin selected from vinylidene and polyvinyl fluoride. 6. The fluororesin film is ethylene-based.
The coating material for agriculture according to claim 1, which is a film of a tetrafluoroethylene-based copolymer. 7. The ethylene-tetrafluoroethylene copolymer has an ethylene / tetrafluoroethylene content molar ratio in the range of 40/60 to 60/40, and has the formula CH ₂ ═CH—C _n F _{2n + 1} (where n is an integer of 2 to 10) ethylene-tetrafluoroethylene-based polymer having a perfluoroalkylvinyl monomer unit content of 0.1 to 10 mol%. The covering material for agriculture according to claim 4, which is a copolymer.