JP2011057756A - Agricultural film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an agricultural film exhibiting excellent ultraviolet ray-shielding properties as well as excellent pesticide properties. <P>SOLUTION: The agricultural film comprises a benzotriazole ultraviolet absorber of general formula (1) (wherein R<SP>1</SP>and R<SP>2</SP>may be the same or different and are each independently a ≥1C linear or branched substituting group). <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an agricultural film having excellent ultraviolet shielding properties and excellent pest control properties when processed into a film or sheet, and particularly exhibits excellent bleed-out resistance even when the film thickness is thin, and has been used for a long time. In particular, the present invention relates to an agricultural film that is difficult to lose its ultraviolet absorption ability, and that is excellent in controlling the growth of pests and fungi, pest control, and deterioration prevention of lining materials in the house environment.

  Agricultural houses have become larger year by year, and the film expansion work for covering the houses with films has become more labor-intensive. On the other hand, the number of farmers is declining year by year and aging is progressing, and it is not easy to secure manpower for annual expansion work. In view of such a situation, the film to be spread in the house is a film that is easy to stretch and has a long use period until re-covering as much as possible, in other words, has a long life of 2 years or more and can maintain the initial performance over a long period of time. There is a need to develop high performance agricultural films.

  Among these coating materials, agricultural polyolefin-based resin films mainly composed of polyolefin-based resins are lighter in density than vinyl chloride resins, generate little toxic gas even when incinerated, and need to add a plasticizer. Therefore, there is no problem of curing due to bleed-out of the plasticizer, and wide film that does not require adhesive processing for splicing by the inflation molding method can be provided at low cost. It is coming.

  On the other hand, a method of adding a small amount of an ultraviolet absorber to an agricultural film to cut off a part of the ultraviolet light to prevent the deterioration of the agricultural film in the ultraviolet is known, but today, the ultraviolet region (300 nm to 380 nm) is further increased. Attempts have been made to reduce pesticide cultivation by creating UV-cutting films that cut all UV rays substantially completely, and controlling the growth and control of pests and fungi in the house environment.

  However, even with the above-mentioned UV-cutting properties, the effect of controlling insects and pests is not yet sufficient, and improvement has been demanded. Large whitefly is a typical pest of crops widely cultivated in the house such as tomatoes, cucumbers, and melons. Due to recent food safety requirements, there is a specific method for controlling these pests without using pesticides. It was desired.

  On the other hand, an agricultural film has been proposed in which a large amount of an ultraviolet absorber capable of cutting an ultraviolet region of about 300 nm to 380 nm is added to the film to cut an ultraviolet region of 300 to 400 nm (Japanese Patent Application Laid-Open (JP-A)). 2009-159839). However, there is a limit to the concentration of the UV absorber that can be compatible in the resin, and it is known that the limit concentration depends on the structure of the UV absorber. That is, even if a large amount of conventional ultraviolet absorbers are simply added, there is a problem of bleeding out, and there is a problem that transparency of the film is deteriorated and anti-fogging property is deteriorated. In order to solve this problem, a method of increasing the film thickness and decreasing the concentration in the resin has been proposed (Japanese Patent Application Laid-Open No. 2009-159839). However, even if the film could be stretched, the above-mentioned performance degradation due to bleed-out during use was unavoidable.

  In recent years, there is an increasing demand for food safety and security, and there is an increasing need for pesticide-free and pesticide-free cultivation of vegetables produced in greenhouse horticulture. Against this background, agricultural films used for horticultural horticulture are expected to have a higher level of pest control effect, and cut off more UV light than the visible light part used for photosynthesis. The development of a film that can be used was expected.

  Therefore, an object of the present invention is to provide specific constituent requirements for an agricultural film that can be expected to have an unprecedented ultraviolet shielding effect, particularly a pest control effect over a long period of time.

JP 2009-159839 A

  As a result of intensive studies, the present inventors have found that, when an ultraviolet absorber having the following specific structure is used, ultraviolet rays of 300 nm to 420 nm are substantially completely shielded. The present inventors have found that the above problems can be solved in a film (substantially completely shielded: the average value of the total light transmittance measured every 1 nm at 300 to 420 nm is less than 2%), thereby completing the present invention.

  Agricultural film characterized by containing a benzotriazole type ultraviolet absorber represented by the following general formula (1) (R1 and R2 may be the same or different, and each independently has 1 or more carbon atoms) Place)

  Agricultural film, wherein R1 in general formula (1) is a tBu group and R2 is a Me group

  In the present invention, it has been found that by substantially completely blocking ultraviolet rays of 300 nm to 420 nm, it is possible to suppress the behavior of pests in house cultivation such as on-site whitefly, especially in the polyolefin-based multilayer film for agriculture. The inventors have found that by using an ultraviolet absorber having at least one of wavelengths of 360 nm or more, good performance is shown, and the present invention has been completed.

  Onsite whitefly causes damage by larvae sucking plant juice and deteriorating the commercial value of fruits and premature leaf damage. Furthermore, there are damages caused by the presence of soot pathogens in the excrement and black contamination of the plant body, and this is an important problem in facility horticulture.

  Under the circumstances, the present invention unexpectedly uses a specific addition method, particularly by using a UV absorber having a specific structure for an agricultural film, and surprisingly, it has a high level of bleed-out resistance and pest behavior control (reproduction control). : Control), growth control of diseased fungi and fungi, and prevention of deterioration of lining materials can be maintained in a well-balanced manner over a long period of time, and as a result, it was found that it can provide important performance as an agricultural film. Is.

  On the other hand, if it continues to be irradiated with strong ultraviolet rays, the ultraviolet absorber in the film may be modified and the film may be colored, which causes a decline in commercial value due to the inhibition of transparency of the film, There was a need for a specific solution.

  Under the background, the present invention has been made as a result of finding that, by combining with a UV absorber having a specific structure, coloring of the film by UV rays can be prevented, and useful performance as an agricultural film can be sustained for a long period of time. It is.

Total light transmission characteristics of the film used in the test. Total light transmission characteristics of the film used for the test: combination with a triaryltriazine type UV absorber. Test method of on-site whitefly behavior inhibition test.

Hereinafter, the present invention will be described in detail.
The agricultural film in the present invention is an agricultural film using a known synthetic resin as a base resin, and particularly exhibits an effect with a multilayer film using a polyolefin resin. The polyolefin agricultural film according to the present invention is a film having a laminated structure of three or more layers having at least an outer layer, an intermediate layer, and an inner layer. Here, the outer layer means a layer that becomes the outer side when it is extended to a house, the inner layer means a layer that becomes the inner side when the house is extended, and the intermediate layer means a layer sandwiched between the outer layer and the inner layer. Say. Hereinafter, the outer layer and the inner layer may be collectively referred to as a surface layer. Further, as long as the effects of the present invention are not impaired, a resin layer may be further laminated between the inner layer and the intermediate layer, or between the outer layer and the intermediate layer, or the outer layer, the intermediate layer, the inner layer, and the like may be composed of two layers. The aspect made into a multilayer film of four or more layers is also included in the scope of the present invention. In this case, the intermediate layer is a layer other than the outer layer and the inner layer (other than the surface layer).

  The layer thickness ratio of the outer layer / intermediate layer / inner layer in the present invention is not particularly limited. For example, the layer is 1/1/1 to 1/5/1, preferably 1/2/1 to 1/3/1. Formed in ratio.

In addition, the outer layer, the intermediate | middle layer, and inner layer said by this invention mean the layer comprised from the resin composition which added the other component to the resin main component which functions as an agricultural film. Therefore, as will be described later, a coating-type antifogging coating that is thinly applied on the inside of the inner layer for the purpose of antifogging properties, and other coatings that are formed on the outside of the outer layer for other purposes, The concept of the outer layer will be excluded.
For the polyolefin film for agricultural use of the present invention, resins conventionally used as agricultural film resins such as polyolefin resin, vinyl chloride resin, polyethylene terephthalate resin, etc. can be used. The effect of the present invention is effectively exhibited in the resin.
Examples of polyolefin resins include α-olefin homopolymers, copolymers of different monomers mainly containing α-olefins, polyunsaturated compounds such as α-olefins and conjugated dienes or nonconjugated dienes, Examples include copolymers with acrylic acid, methacrylic acid, vinyl acetate, and the like, such as high density, low density or linear low density polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-butene copolymer, ethylene. Examples include -4-methyl-1-pentene copolymer, ethylene-vinyl acetate copolymer, and ethylene-acrylic acid copolymer. Among these, low density polyethylene having a density of 0.890 to 0.935, ethylene-α-olefin copolymer, and ethylene-vinyl acetate copolymer having a vinyl acetate content of 30% by weight or less are transparent and weather resistant. It is preferable as an agricultural film from the viewpoint of properties and price.
In the present invention, an ethylene-α-olefin copolymer resin obtained by copolymerization with a metallocene catalyst can be used as at least one component of the polyolefin resin.

  This is usually referred to as metallocene polyethylene, and is a copolymer of ethylene and an α-olefin such as butene-1, hexene-1, 4-methylpentene-1, octene.

  The ethylene-α-olefin copolymer used as at least one component of the polyolefin resin of the present invention preferably exhibits the following physical properties.

Melt flow rate (MFR)
The MFR measured according to JIS-K7210 is 0.01 to 10 g / 10 min, preferably 0.1 to 5 g / 10 min. If the MFR is larger than this range, the film meanders during molding and is not stable. On the other hand, if the MFR is too smaller than this range, the resin pressure at the time of molding increases and a load is applied to the molding machine. Therefore, the increase in pressure must be suppressed by reducing the production amount, which is not practical.

Density The density measured by JIS-K7112 is 0.880 to 0.930 g / cm ³ , preferably 0.880 to 0.920 g / cm ³ . When the density is larger than this range, the transparency is deteriorated. On the other hand, if the density is smaller than this range, blocking occurs due to stickiness of the film surface, resulting in poor practicality.

Molecular weight distribution The molecular weight distribution (weight average molecular weight / number average molecular weight) determined by gel permeation chromatography (GPC) is 1.5 to 3.5, preferably 1.5 to 3.0. . When the molecular weight distribution is larger than this range, the mechanical strength is lowered, which is not preferable. If the molecular weight distribution is smaller than this range, the film meanders during molding and is not stable.

  The ethylene-vinyl acetate copolymer resin used in the present invention preferably has a vinyl acetate content of 3 to 25% by weight, more preferably 5 to 20% by weight. If the vinyl acetate content is less than this range, the resulting film will be hard and will tend to wrinkle and sag when stretched in a house, which will have a negative effect on anti-fogging properties. If it is larger than the range, the melting point of the resin is low, so that the film loosens at high temperatures in summer during house extension, and is easily broken by wind and flapping with the house structure.

The agricultural film in this invention can obtain the film transmittance | permeability prescribed | regulated to this application by including at least 1 or more types of the benzotriazole type ultraviolet absorber whose at least one is 360 nm or more among absorption peak wavelengths.
In particular, a benzotriazole type ultraviolet absorber described in the following general formula (1) (R1 and R2 may be the same or different and each independently represents a linear or branched substituent having 1 or more carbon atoms). By using it, a good ultraviolet absorbing ability can be imparted to the film.

  Furthermore, when R1 in the general formula (1) is a tBu group and R2 is a Me group, it is possible to provide a high level balance such as good ultraviolet absorption ability and cost. Since the relationship between the structure of the ultraviolet absorbent and the ultraviolet absorbing ability depends on the position of the substituent and the electron withdrawing / donating properties, good performance can be obtained within the range defined by the general formula (1).

  The agricultural film in the present invention is characterized in that ultraviolet rays of 300 nm to 420 nm are substantially completely shielded (substantially completely shielded: total light transmittance measured every 1 nm at 300 to 420 nm. Of less than 2%). Such ultraviolet absorbing ability up to the long wavelength region can be obtained by using the ultraviolet absorbent described in this application for agricultural films. In the prior art, it is difficult to obtain such a good ultraviolet absorbing ability, and furthermore, it is difficult to stably obtain the ultraviolet absorbing ability up to a long wavelength region over a long period of time in the conventional technique.

  The agricultural film in the present invention contains a triaryltriazine type ultraviolet absorber described in the following general formula (2) in addition to the ultraviolet absorber described in the above general formula (1), so that the film can absorb ultraviolet rays as a film. In addition to providing high performance, the triaryltriazine-type UV absorber has good fastness (resistance to strong UV rays), and can provide high levels of color prevention and UV cut sustainability. .

（式中、Ｒ３〜Ｒ７は、それぞれ独立して水素原子、又は炭素数１〜１０のアルキル基を表す。）

(Wherein R3 to R7 each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.)

  In particular, when R3 in the formula (2) is a hexyl group and R4 to R7 are hydrogen atoms, or R3 in the formula (2) is an octyl group and R4 to R7 are methyl groups, It is preferable because it can balance performance and cost.

  The agricultural film in this invention can use a well-known ultraviolet absorber together in the range which does not affect the calculated | required effect. These ultraviolet absorbers can be used in combination with the ultraviolet absorber according to the present application as long as they do not interfere with the effects of the present invention. Moreover, inorganic oxide type ultraviolet absorbers including metal oxides such as zinc oxide and cerium oxide can be used in combination.

  Examples of other UV absorbers that can be used in combination include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 5,5′-methylenebis (2-hydroxy- 2-hydroxybenzophenones such as 4-methoxybenzophenone); 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-ditert-butylphenyl) Benzotriazole, 2- (2′-hydroxy-3 ′, 5′-ditert-butylphenyl) -5-chlorobenzotriazole, 2- (2′-hydroxy-3′-tert-butyl-5′-methylphenyl) ) -5-chlorobenzotriazole, 2- (2′-hydroxy-5′-tert-octylphenyl) benzoto 2- (2 such as azole, 2- (2′-hydroxy-3′.5′-dicumylphenyl) benzotriazole, 2,2′-methylenebis (4-tert-octyl-6-benzotriazolyl) phenol '-Hydroxyphenyl) benzotriazoles; phenyl salicylate, resorcinol monobenzoate, 2,4-ditertiarybutylphenyl-3', 5'-ditertiarybutyl-4'-hydroxybenzoate, 2,4-ditertiary Benzoates such as amylphenyl-3 ′, 5′-ditert-butyl-4′-hydroxybenzoate, hexadecyl-3,5-ditert-butyl-4-hydroxybenzoate; 2-ethyl-2′-ethoxyoxani Substituted oxanilides such as Lido, 2-ethoxy-4′-dodecyloxanilide; ethyl-α-cyano-β, β-diphenyl Acrylates, cyanoacrylates such as methyl-2-cyano-3-methyl-3- (p-methoxyphenyl) acrylate.

  The content of the ultraviolet absorber in the agricultural film of the present invention is less than 5% by weight, preferably 0.1 to 3% by weight, more preferably 0.2 to 1.5% by weight, based on the total film. is there. When the content is less than the above range, the ultraviolet ray shielding effect is low. When the content exceeds the above range, the cost is disadvantageous, and when it is applied to a general agricultural film, there is a problem in whitening due to bleeding out. These contents are values determined by selection of the type of resin and the type of ultraviolet absorber.

  In this invention, it is preferable that the ultraviolet absorber of General formula (1) is added more than the quantity which shields the ultraviolet-ray of the area | region of 300 nm-420 nm substantially completely in the agricultural film containing this. The phrase “substantially completely shielded” means that the average value of the transmittance at each wavelength is less than 2% when the total light transmittance is measured every 1 nm at 300 to 420 nm. Furthermore, the average value of the transmittance is preferably 1% or less, and an effect of ultraviolet shielding is easily obtained.

  As a preferred embodiment of the present invention, as described in JP-A-2003-61483, the content (% by weight) of the ultraviolet absorber (total of two or more) relative to the resin composition per unit volume of the intermediate layer is X, X> Y, and X> Z, where Y is the UV absorber content (% by weight) per unit volume of Z and Z is the UV absorber content (% by weight) per unit volume in the outer layer It is preferable that the effect of maintaining the ultraviolet absorbing ability over a long period is remarkable. For example, there is a method in which an ultraviolet absorber is added to other than the surface layer of the multilayer film (other than the house inner layer and the house outer layer: an intermediate layer).

In particular, when two specific types of ultraviolet absorbers of the present invention (ultraviolet absorbers represented by the general formula (1) and general formula (2)) are used to form this layer structure, each individual ultraviolet absorber is similar. Even when the layer configuration is used, or when the same layer configuration is used by combining two types of other ultraviolet absorbers, the effect is remarkable.
Here, Y and Z may be Y = Z or may be different. A particularly preferred embodiment is the case where Y = Z = 0.

  Specifically, X, which is the content of the ultraviolet absorber with respect to the resin composition in the intermediate layer, is 0.1 to 3.0% by weight, preferably 0.15 to 2.0% by weight, and more preferably 0. The range of 2 to 1.0% by weight is mentioned. Y and Z include 0 to 2.0% by weight, preferably 0 or 0.001 to 0.5% by weight.

  Furthermore, as a preferred embodiment of the present invention, there is an agricultural polyolefin multilayer film having a laminated structure of at least three layers having at least an outer layer, an intermediate layer, and an inner layer, and an ultraviolet absorber is blended in the outer layer and the inner layer (surface layer). Without mentioning, an agricultural polyolefin-based multilayer film characterized in that an ultraviolet absorber is blended in the intermediate layer.

  The agricultural film of the present invention can contain an infrared absorber (heat retention agent). In particular, the polyolefin-based multilayer film contains an inorganic compound containing at least one atom selected from Si, Al, Mg, Ca, and Li as at least one layer of the multilayer film having at least three layers. Thus, good heat retention can be imparted. As a measure of the amount added, a good infrared absorption effect (heat retention) can be imparted when it is contained in about 3% or more in terms of the total film thickness. As an inorganic compound which can be used, a well-known thing can be mentioned, for example as an infrared absorber (heat retention agent) and a filler. When such an inorganic compound is added in a small amount, heat retention cannot be imparted, and when it is excessive, transparency is hindered, making it difficult to provide the necessary performance as an agricultural film.

  The infrared absorbent (heat retention agent) is inorganic fine particles having infrared absorbing ability, and these can be used alone or in combination of two or more. The inorganic fine particles that can be used are not particularly limited, but are inorganic compounds containing at least one atom selected from the components: Si, Al, Mg, Ca, Li. For example, magnesium oxide, calcium oxide, aluminum oxide, silicon oxide, lithium hydroxide, magnesium hydroxide, calcium hydroxide, aluminum hydroxide, magnesium carbonate, calcium carbonate, calcium sulfate, magnesium sulfate, aluminum sulfate, lithium phosphate, calcium phosphate , Magnesium silicate, calcium silicate, aluminum silicate, calcium aluminate, magnesium aluminate, sodium aluminosilicate, potassium aluminosilicate, calcium aluminosilicate, kaolin, clay, talc, mica, zeolite, hydrotalcite compound, lithium aluminum composite Hydroxides, aluminum / lithium / magnesium composite carbonate compounds, aluminum / lithium / magnesium composite silicate compounds, magnesium / aluminum Um silicon composite hydroxide, magnesium aluminum silicon composite sulfate compounds, magnesium aluminum silicon composite carbonate compound, a metal complex hydroxide salt containing more anions. These may be obtained by dehydrating crystal water.

  The inorganic fine particles used as the infrared absorber (heat retention agent) may be natural products or synthetic products. The inorganic fine particles can be used without being limited by the crystal structure, crystal particle diameter, and the like.

  The inorganic fine particles used as the infrared absorbing agent (heat retention agent) have a surface having a higher fatty acid such as stearic acid, a higher fatty acid metal salt such as an alkali metal oleate, or an organic sulfonic acid such as an alkali metal dodecylbenzenesulfonate. Those coated with metal salts, higher fatty acid amides, higher fatty acid esters or waxes can also be used.

  The inorganic fine particles used as the infrared absorber (heat retention agent) can be used alone or in combination of two or more. The average particle diameter is preferably in the range of 0.05 to 15 μm, more preferably 0.1 to 10 μm. If the average particle size of the inorganic fine particles is smaller than the above range, the dispersibility in the resin is inferior, and the appearance of the film is deteriorated and the appearance of the film is deteriorated. The handling is severely inferior. On the other hand, if the average particle size of the inorganic fine particles is larger than the above range, the transparency is inferior or clogging occurs in the extruder breaker screen, and the productivity deteriorates.

  The usage-amount of the said infrared absorber (heat retention agent) is 3-30 weight part in a film whole layer, More preferably, it is 3-20 weight part, More preferably, it is 3-15 weight part. If it is less than 3 parts by weight, infrared rays cannot be absorbed sufficiently, and if it exceeds 30 parts by weight, transparency and mechanical strength as an agricultural film are inferior and disadvantageous in cost.

  The filler may be, for example, silica, talc, aluminum hydroxide, hydrotalcite, calcium sulfate, calcium silicate, calcium hydroxide, water, in order to suppress stickiness of the film or to further improve heat retention. Magnesium oxide, kaolin clay, mica, alumina, magnesium carbonate, sodium aluminate, conductive zinc oxide, lithium phosphate and the like are used. One type of these fillers may be used, or two or more types may be used in combination.

  A hindered amine compound can be added to at least one layer in the multilayer film as a weathering agent in the agricultural polyolefin-based multilayer film used in the present invention. Moreover, this hindered amine compound can be used 1 type or in combination of 2 or more types. Of course, the same type may be included in all layers of the hindered amine compound. For example, the innermost layer and the outermost layer (outer surface of the house) contain a high molecular weight type that does not bleed out, and the other layers are usually formulated for agriculture. The hindered amine compound to be used can also be contained. These high molecular weight hindered amine compounds may be copolymerized with ethylene or other monomers (for example, ethylene / cyclic aminovinyl compound copolymer), or may be grafted onto polymers such as polyethylene. In that case, for example, the same layer may contain an ethylene / cyclic aminovinyl compound copolymer and a hindered amine light stabilizer usually blended for agriculture.

  A known hindered amine compound containing a piperidine ring can be used as the hindered amine light weathering agent usually blended for use in agriculture. If the number of piperidine rings in the piperidine ring-containing hindered amine compound is less than 2, sufficient weather resistance is difficult to obtain, and if the molecular weight is less than 500, volatilization is likely to occur and it may be difficult to obtain long-term weather resistance. . The number of piperidine rings in the piperidine ring-containing hindered amine compound is preferably 2 to 50, and the molecular weight is preferably 750 or more.

  Examples of the piperidine ring-containing hindered amine compound include bis (1,2,2,6,6-pentamethyl-4-piperidyl) -2-butyl-2- (3,5-ditert-butyl-4-hydroxybenzyl). ) Malonate, tetra (2,2,6,6-tetramethyl-4-piperidyl) butanetetracarboxylate, tetra (1,2,2,6,6-pentamethyl-4-piperidyl) butanetetracarboxylate, bis ( 2,2,6,6-tetramethyl-4-piperidyl) .di (tridecyl) butanetetracarboxylate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) .di (tridecyl) butanetetra Carboxylate, 3,9-bis [1,1-dimethyl-2- {tris (2,2,6,6-tetramethyl-4-piperidyloxy Rubonyloxy) butylcarbonyloxy} ethyl] -2,4,8,10-tetraoxaspiro [5.5] undecane, 3,9-bis [1,1-dimethyl-2- {tris (1,2,2) , 6,6-pentamethyl-4-piperidyloxycarbonyloxy) butylcarbonyloxy} ethyl] -2,4,8,10-tetraoxaspiro [5.5] undecane, 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-tetraaza Dodecane, 1- (2-hydroxyethyl) -2,2,6,6-tetramethyl-4-piperidinol / dimethyl succinate condensate, 2-tert-octylamino-4,6-dichloro-s-triazine N, N′-bis (2,2,6,6-tetramethyl-4-piperidyl) hexamethylenediamine condensate, N, N′-bis (2,2,6,6-tetramethyl-4-piperidyl) And hexamethylenediamine / dibromoethane condensate. Examples of commercially available hindered amine compounds that can be used are TINUVIN 770, TINUVIN 780, TINUVIN 144, TINUVIN 622LD, TINUVIN NOR 371FF, CHIMASSORB 119FL, CHIMASSORB 944 (above, manufactured by Ciba), Sanol LS-765 (Sankyo R Co., Ltd.) -63, MARK LA-68, MARK LA-68, MARK LA-62, MARK LA-67, MARK LA-57, LA-900 (manufactured by Asahi Denka Co., Ltd.), UV-3346, UV-3529, UV-3581, UV-3853 (above, manufactured by Cytec), Hostabin N20, Hostabin N24, Hostabin N30, Hostabin 845, Sanduboa PR-31, Nyrostub SE Examples thereof include ED (manufactured by Clariant Japan), UVINUL5050H (manufactured by BASF Japan), and XJ100H (Nippon Polyethylene Co., Ltd.). These piperidine ring-containing hindered amine compounds are used alone or in combination of two or more.

  In the thermoplastic resin film of the present invention, various additives usually used for synthetic resins can be used in combination. Examples of these additives include metal organic acid salts, basic organic acid salts and overbased organic acid salts, hydrotalcite compounds, epoxy compounds, β-diketone compounds, polyhydric alcohols, and halogen oxyacid salts. Sulfur-based, phenol-based and phosphite-based antioxidants, heat stabilizers, lubricants, antistatic agents, colorants, antiblocking agents, antifogging agents, antifogging agents, and the like.

  Examples of the metal species constituting the organic acid salt, basic organic acid salt and overbased organic acid salt of the metal include Li, Na, K, Ca, Ba, Mg, Sr, Zn, Cd, Sn, Cs, Examples of the organic acid include carboxylic acid, organic phosphoric acid, and phenol. Examples of the carboxylic acid include acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, Caprylic acid, neodecanoic acid, 2-ethylhexylic acid, pelargonic acid, capric acid, undecanoic acid, lauric acid, tridecanoic acid, myristic acid, palmitic acid, isostearic acid, stearic acid, 12-hydroxystearic acid, behenic acid, montanic acid, Elaidic acid, oleic acid, linoleic acid, linolenic acid, thioglycolic acid, mercaptopropionic acid, octyl mercapto Lopionic acid, benzoic acid, monochlorobenzoic acid, p-tert-butylbenzoic acid, dimethylhydroxybenzoic acid, 3,5-ditert-butyl-4-hydroxybenzoic acid, toluic acid, dimethylbenzoic acid, ethylbenzoic acid, cumin Acids, n-propylbenzoic acid, acetoxybenzoic acid, salicylic acid, p-tertiary octylsalicylic acid and other monovalent carboxylic acids, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid , Divalent carboxylic acids such as sebacic acid, maleic acid, fumaric acid, citraconic acid, metaconic acid, itaconic acid, aconitic acid, thiodipropionic acid, phthalic acid, isophthalic acid, terephthalic acid, oxyphthalic acid, chlorophthalic acid, etc. Monoester or monoamide compound, butanetricarboxylic acid, butane Examples thereof include di- or triester compounds of trivalent or tetravalent carboxylic acids such as tracarboxylic acid, hemimellitic acid, trimellitic acid, merophanic acid, and pyromellitic acid, and examples of the organic phosphoric acid include mono- or dioctylphosphoric acid. Acid, mono or didodecyl phosphoric acid, mono or dioctadecyl phosphoric acid, mono or di- (nonylphenyl) phosphoric acid, phosphonic acid nonylphenyl ester, phosphonic acid stearyl ester, etc., and the phenols include phenol, cresol , Xylenol, methylpropylphenol, methyl tertiary octylphenol, ethylphenol, isopropylphenol, tertiary butylphenol, n-butylphenol, diisobutylphenol, isoamylphenol, diamylphenol, isohexylphenol Enol, octylphenol, isooctylphenol, 2-ethylhexylphenol, tertiary octylphenol, nonylphenol, dinonylphenol, tertiary nonylphenol, decylphenol, dodecylphenol, octadecylphenol, cyclohexylphenol, phenylphenolphenol, cresol, ethylphenol, cyclohexylphenol, nonylphenol And dodecylphenol.

  Although there is no restriction | limiting in particular about the said anti-fogging agent, It consists of polyhydric alcohol and higher fatty acids including well-known various nonionic surfactant, anionic surfactant, cationic surfactant, etc. A polyhydric alcohol partial ester type is preferred. Specific examples of such an antifogging agent include, for example, nonionic surfactants such as sorbitan monostearate, sorbitan monomyristate, sorbitan monopalmitate, sorbitan monobehenate, sorbitan / alkylene glycol condensate and fatty acid. Sorbitan surfactants such as esters with glycerol monopalmitate, glycerol monostearate, glycerol monolaurate, diglycerol monopalmitate, glycerol dipalmitate, glycerol distearate, diglycerol monopalmitate monostearate Glycerin-based surfactants such as glycerol, monoglycerate, triglycerin monostearate, triglycerin distearate or alkylene oxide adducts thereof, polyethylene glycol monostearate, polyethylene glycol Polyethylene glycol surfactants such as coal monopalmitate, polyethylene glycol alkyl phenyl ether, and other trimethylolpropane surfactants such as trimethylolpropane monostearate, and pentaerythritol monopalmitate, pentaerythritol monostearate, etc. Erythritol surfactant, alkylene oxide adduct of alkylphenol; sorbitan / glycerin condensate and fatty acid ester, sorbitan / alkylene glycol condensate and fatty acid ester; diglycerin dioleate sodium lauryl sulfate, dodecylbenzenesulfonic acid Sodium, cetyltrimethylammonium chloride, dodecylamine hydrochloride, lauric acid laurylamide ethyl phosphate It can be exemplified triethylammonium cetyl ammonium iodide, oleyl amino diethylamine hydrochloride, and those containing dodecyl pyridinium salts, etc. and their isomers.

  Examples of the anti-fogging agent include a fluorine-based surfactant and a silicone-based surfactant. Specific examples of the fluorine-based surfactant include, instead of H bonded to C of the hydrophobic group of a normal surfactant. In addition, a surfactant having a part or all thereof substituted with F, particularly a surfactant containing a perfluoroalkyl group or a perfluoroalkenyl group. The above various additives can be used alone or in combination of two or more. Examples of the fluorine-containing compound having a perfluoroalkyl group include an anionic fluorine-containing surfactant, a cationic fluorine-containing surfactant, an amphoteric fluorine-containing surfactant, a nonionic fluorine-containing surfactant, and a fluorine-containing oligomer. can give.

  The amount of the fluorine-containing compound having a perfluoroalkyl group is preferably 0.001 to 10 parts by weight, more preferably 0.01 to 5 parts by weight with respect to 100 parts by weight of the thermoplastic resin. If the amount of the fluorine-containing compound used is less than 0.001 part by weight, the antifogging effect is hardly exhibited, and if it exceeds 10 parts by weight, the effect is saturated, which is not preferable.

  Examples of the phenol-based antioxidant include 2,6-ditert-butyl-p-cresol, 2,6-diphenyl-4-octadecyloxyphenol, stearyl (3,5-ditert-butyl-4- Hydroxyphenyl) -propionate, distearyl (3,5-ditert-butyl-4-hydroxybenzyl) phosphonate, thiodiethylene glycol bis [(3,5-ditert-butyl-4-hydroxyphenyl) propionate], 1,6 -Hexamethylene bis [(3,5-ditert-butyl-4-hydroxyphenyl) propionate], 1,6-hexamethylene bis [(3,5-ditert-butyl-4-hydroxyphenyl) propionic acid amide] 4,4′-thiobis (6-tert-butyl-m-cresol), 2,2′-methylenebis (4-methyl-6- Tributylphenol), 2,2′-methylenebis (4-ethyl-6-tert-butylphenol), bis [3,3-bis (4-hydroxy-3-tert-butylphenyl) butyric acid] glycol ester, 4, 4'-butylidenebis (6-tert-butyl-m-cresol), 2,2'-ethylidenebis (4,6-ditert-butylphenol), 2,2'-ethylidenebis (4-secondarybutyl-6- Tert-butylphenol), 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, bis [2-tert-butyl-4-methyl-6- (2-hydroxy-3) -Tert-butyl-5-methylbenzyl) phenyl] terephthalate, 1,3,5-tris (2,6-dimethyl-3-hydroxy-4-tert-butylbenzyl) isocyanurate 1,3,5-tris (3,5-ditert-butyl-4-hydroxylbenzyl) isocyanurate, 1,3,5-tris (3,5-ditert-butyl-4-hydroxybenzyl) 2,4,6-trimethylbenzene, 1,3,5-tris [(3,5-ditert-butyl-4-hydroxyphenyl) propionyloxyethyl] isocyanurate, tetrakis [methylene-3- (3,5 -Di-tert-butyl-4-hydroxyphenyl) propionate] methane, 2-tert-butyl-4-methyl-6- (2-acryloyloxy-3-tert-butyl-5-methylbenzyl) phenol, 3,9- Bis [1,1-dimethyl-2-{(3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy} ethyl] -2,4,8,10-tetraoxaspiro [5. ] Undecane, triethylene glycol bis [(3-tert-butyl-4-hydroxy-5-methylphenyl) propionate], n-octadecyl 3- (3 ', 5'-di-t-butyl-4'-hydroxyphenyl) ) Propionate, tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyloxymethyl] methane and the like.

  Examples of the sulfur-based antioxidant include dialkylthiodipropionates such as dilauryl thiodipropionate, dimyristyl, and distearyl, and β-alkyl mercapto of polyols such as pentaerythritol tetra (β-dodecyl mercaptopropionate). And propionic acid esters.

  Examples of the phosphite-based antioxidant include trisnonylphenyl phosphite, tris (2,4-ditert-butylphenyl) phosphite, tris [2-tert-butyl-4- (3-tert-butyl- 4-hydroxy-5-methylphenylthio) -5-methylphenyl] phosphite, tridecyl phosphite, octyl diphenyl phosphite, di (decyl) monophenyl phosphite, monodecyl diphenyl phosphite, mono (dinonylphenyl) Bis (nonylphenyl) phosphite, di (tridecyl) pentaerythritol diphosphite, distearyl pentaerythritol diphosphite, di (nonylphenyl) pentaerythritol diphosphite, bis (2,4-ditertiarybutylphenyl) penta Erythritol diphosphie Bis (2,6-ditert-butyl-4-methylphenyl) pentaerythritol diphosphite, tetra (tridecyl) isopropylidenediphenol diphosphite, tetra (tridecyl) isopropylidenediphenol diphosphite, tetra (C 12-15 mixed alkyl) -4,4′-n-butylidenebis (2-tert-butyl-5-methylphenol) diphosphite, hexa (tridecyl) -1,1,3-tris (2-methyl-4-hydroxy-) 5-tert-butylphenyl) butanetriphosphite, tetrakis (2,4-ditert-butylphenyl) biphenylene diphosphonite, 2,2′-methylenebis (4,6-ditert-butylphenyl) (octyl) phosphite , Tetrakis (2,4-di-t-butylphenyl) 4,4′-biphenylene-di Phosphonites, 2,2-methylenebis (4,6-di -t- butyl phenyl) octyl phosphite, and the like.

  Examples of the colorant include phthalocyanine blue, phthalocyanine green, hansa yellow, alizarin lake, titanium oxide, zinc white, ultramarine blue, permanent red, quinacridone, and carbon black.

  Examples of the anti-blocking agent include diatomaceous earth, synthetic silica, talc, mica and zeolite. These anti-blocking agents can be used alone or in combination of two or more, and the range of usually 0.01 to 0.5% by weight is preferred.

  The thermoplastic resin film of the present invention contains the above-described components in combination, and can further contain the following optional components that can be contained in the thermoplastic resin film of the present invention as necessary. . Optional components include other stabilizers, impact resistance improvers, cross-linking agents, fillers, foaming agents, antistatic agents, nucleating agents, plate-out preventing agents, surface treatment agents, flame retardants, fluorescent agents, anti-glare agents Agents, bactericides, metal deactivators, mold release agents, pigments, processing aids and the like.

  The thermoplastic resin film of the present invention is weighed in a necessary amount for blending various additives, and blending machines such as a ribbon blender, a Banbury mixer, a Henschel mixer, a super mixer, a single or twin screw extruder, a roll, A kneader or other conventionally known blender or mixer may be used. In order to form the resin composition thus obtained into a film, a method known per se, for example, a melt extrusion molding method (including a T-die method and an inflation method), calendar processing, roll processing, extrusion molding processing, Blow molding, inflation molding, melt casting, pressure molding, paste processing, powder molding, and the like can be suitably used.

  The thickness of the thermoplastic resin film of the present invention is not particularly limited for the purpose of obtaining the effects of the present invention, but the influence of bleed out is reduced by increasing the film thickness (decreasing the UV absorber concentration). I can do it. In particular, the range of 0.03 to less than 1.0 mm is preferable in terms of strength and cost, the range of 0.05 to 0.75 mm is more preferable, and the range of 0.05 to 0.5 mm is more preferable. . If it is less than this range, there is a problem with strength.

In the present invention, when a polyolefin resin is used for the base material layer, an antifogging film can be formed in contact with the innermost layer of the polyolefin base material.
As the anti-fogging coating film in the present invention, an anti-fogging coating film which can be used for an already known agricultural film can be applied. Preferably, an antifogging coating film mainly composed of an inorganic colloid material and a hydrophilic organic compound or an antifogging coating film mainly composed of an inorganic colloid material and an acrylic resin can be used.

  Examples of anti-fogging coatings mainly composed of an inorganic colloid material and a hydrophilic organic compound that can be used in the present invention include, for example, Japanese Patent Publication No. 63-45432, Japanese Patent Publication No. 63-45717, Japanese Patent Publication No. 64-2158, and patents. And compounds shown in No. 3094296.

  In addition, a known coating film using an inorganic colloid substance and / or a synthetic resin binder can be formed by laminating.

  In the present invention, an antifogging film mainly composed of an acrylic resin and an inorganic colloidal sol can also be suitably used.

  As one example preferably used as the acrylic resin, at least a total of 60% by weight of a monomer composed of alkyl esters of acrylic acid or methacrylic acid, or an alkyl ester of acrylic acid or methacrylic acid and an alkenylbenzene The monomer mixture and 0 to 40% by weight of copolymerizable α, β-ethylenically unsaturated monomer are subjected to emulsion polymerization in an aqueous medium in the presence of an emulsifier, for example, according to normal polymerization conditions. The hydrophobic acrylic resin which is the obtained water dispersible polymer or copolymer can be mentioned.

  The acrylic resin used in the present invention is preferably a hydrophobic acrylic resin, that is, an alkyl ester of acrylic acid or methacrylic acid as described above, or an alkyl ester of acrylic acid or methacrylic acid and an alkenylbenzene. It is preferable to contain a monomer mixture with at least 60% by weight, preferably 80% by weight or more. When it is less than 60% by weight, the water resistance of the formed film is not sufficient, and therefore, the anti-fogging sustainability may not be exhibited, which is not preferable.

  In particular, the acrylic resin of the present invention preferably has a glass transition temperature of 35 to 80 ° C. If the glass transition temperature is too low, the inorganic colloidal particles are agglomerated several times and tend to be in a non-uniform dispersion state. If it is too high, it is difficult to obtain a transparent uniform film.

  In the present invention, the thickness of the coating film formed on the surface of the substrate film may be selected by using 1/10 or less of the substrate film as a guide, but is not necessarily limited to this range. If the thickness of the coating is larger than 1/10 of the base film, there is a difference in flexibility between the base film and the coating, so that a phenomenon such as peeling of the coating from the base film is likely to occur, and the coating is cracked. This is not preferable because a phenomenon occurs in which the strength of the base film is lowered.

  When the adhesion between the base film and the coating derived from the coating composition is not sufficient, the base film may be subjected to a surface treatment. Examples of the treatment method applied to the surface of the laminated film of the present invention include corona discharge treatment, sputter etching treatment, sodium treatment, and sandblast treatment. In the corona discharge treatment method, discharge is performed between a needle-like or knife-edge electrode and a counter electrode, and a sample is placed between the electrodes, and the film surface contains oxygen such as aldehyde, acid, alcohol peroxide, ketone, ether, etc. This is a process for generating a functional group. In the sputter etching process, a sample is placed between electrodes that are performing low-pressure glow discharge, and a large number of fine protrusions are formed on the film by the impact of positive ions generated by the glow discharge. In the sandblasting process, fine sand is sprayed on the film surface to form a large number of fine irregularities on the surface. Among these surface treatments, corona discharge treatment is preferable from the viewpoints of adhesion to the coating layer, workability, safety, cost, and the like.

  When the thermoplastic resin film for agriculture according to the present invention is actually used, it is preferably stretched so that the side provided with the anti-fogging coating is inside the house or tunnel.

In the present invention, when a polyolefin resin is used for the base material layer, a dustproof coating can be formed in contact with the innermost layer of the polyolefin base material.
As the dustproof coating film in the present invention, a dustproof coating film that can be used for a known agricultural film can be applied. Preferably, a dustproof coating film mainly composed of an acrylic resin or a dustproof coating film mainly composed of an acrylic resin and an ethylene-acrylic copolymer can be used. In the case of applying a dustproof coating film, the substrate can be subjected to pretreatment such as corona treatment similar to that at the time of forming the antifogging coating film.

  The agricultural polyolefin-based multilayer film of the present invention thus obtained can substantially completely shield ultraviolet rays of 300 nm to 420 nm. “Substantially completely shielded” means that the light transmittance is less than 2% in the state of an unused agricultural film.

  EXAMPLES Hereinafter, although this invention is demonstrated further in detail based on an Example and a comparative example, this invention is not limited to the following examples, unless the summary is exceeded.

(1) Preparation of laminated film (both antifogging agent kneading type and antifogging coating application type)
As a three-layer inflation molding device, a 100 mmφ (made by Pla Koken Co., Ltd.) was used for a three-layer die. Manufactured by Giken Co., Ltd.) Outer inner layer extruder temperature 180 ° C., intermediate layer extruder temperature 170 ° C., die temperature 180-190 ° C., blow ratio 2.0-3.0, take-off speed 3-7 m / min, thickness 0 A three-layer laminated film composed of the components shown in Table-1 and Table-2 at .15 and 0.30 mm was obtained. Since these films are used with the end of the tube cut open when the house is stretched, the tube outer layer during film formation becomes the inner layer (inner surface) of the house when stretched when unfolded.

[Composition] The addition amount is as shown in Table 1.
HP-LDPE: Branched polyethylene produced with a high-pressure radical catalyst (MFR: 1.1 g / 10 min, density 0.920) Novatec LD “YF30” manufactured by Nippon Polychem
Metallocene PE: An ethylene / α-olefin copolymer produced with a metallocene catalyst (MFR: 2 g / 10 min, density 0.907) Kernel “KF270” manufactured by Nippon Polychem
EVA (1): ethylene-vinyl acetate copolymer (vinyl acetate content 15% by weight, MFR 2 g / 10 min)
Kimasorb 944: Light stabilizer ethylene / cyclic amino vinyl copolymer manufactured by Ciba Specialty Chemicals: “Novatech LD / XJ100H” manufactured by Nippon Polychem Co., Ltd. MFR = 3 g / 10 min (190 ° C., JIS-K6760) Density = 0.931 g / cm3 (JIS-K6760)
Benzotriazole type ultraviolet absorber A: SB-7021MBCL manufactured by Cypro Kasei Co., Ltd.
2- [5-Chloro (2H) -benzotriazol-2-yl] -4-methoxy-6- (tert-butyl) phenol

Benzotriazole type UV absorber B: TINUVIN 326 manufactured by Ciba Specialty Chemicals
2- [5-Chloro (2H) -benzotriazol-2-yl] -4-methyl-6- (tert-butyl) phenol

Benzotriazole type UV absorber C: TINUVIN 327 manufactured by Ciba Specialty Chemicals
2,4-Di-tert-butyl-6- (5-chlorobenzotriazol-2-yl) phenol

Triazine type ultraviolet absorber A: UV-1164 manufactured by Cytec Corporation
2- [4,6-Bis (2,4-dimethylphenyl) -1,3,5-triazin-2-yl] -5- (octyloxy) phenol

(2) Surface treatment of film The outer layer surface of the obtained tubular film was subjected to corona discharge treatment at a discharge voltage of 120 V, a discharge current of 4.7 A, and a line speed of 10 m / min, and the “wetting index” according to JIS-K6768 was measured. The value was confirmed.

(3) Formation of anti-fogging coating film (anti-fogging coating type)
The main component (silica sol and / or alumina sol) shown in Table 1, a thermoplastic resin, a crosslinking agent, and a liquid dispersion medium were blended to obtain an antifogging agent composition.
The antifogging agent composition was blended as follows.
Inorganic colloidal sol (colloidal silica) 4.0
Thermoplastic resin (Sanmor SW-131) 3.0
Cross-linking agent (TAZM) 0.1
Dispersion medium (water / ethanol = 3/1) 93
(Note) The amount of inorganic colloidal sol is indicated by the amount of inorganic particles, and the amount of thermoplastic resin is indicated by the solid content of the polymer.
Colloidal silica: Snowtex 30 manufactured by Nissan Chemical Industries, average particle size of 15 nm
Sunmole SW-131: acrylic emulsion T.E. A. Z. M: The above antifogging composition was applied to the surface of a base film surface-treated with an aziridine compound (2) manufactured by Mutual Yakuhin Co., Ltd. using a # 5 bar coater. The applied film was kept in an oven at 80 ° C. for 1 minute to volatilize the liquid dispersion medium to form an antifogging coating film. The thickness of the coating film of each obtained film was about 1 μm.

  This time, a test was performed using a type provided with an antifogging coating film (film thickness 150 μm), but the same effect can be obtained with a type in which an antifogging agent is mixed. Moreover, the same effect is acquired even if it is a combination other than the resin used this time, an additive, or film thickness different from this time, unless the summary is changed. The following optical characteristics were measured for each sample used this time. Each measuring method in an Example and a comparative example is shown below.

(1) Total light transmittance Measured with a spectrophotometer (U3500, manufactured by Hitachi, Ltd.), a laminated film (after forming (coating) an antifogging coating on the inner layer side surface) obtained by three-layer inflation molding The values at each wavelength are shown.

(2) Average transmittance was calculated by averaging the transmittance per 1 nm measured by the method of average transmittance (1).

(3) UV cut property The transmittance calculated by the method of (2) was classified according to the following criteria.
○ ・ Transmittance average value (%) at 300 to 420 nm is less than 2% × ・ Transmittance average value (%) at 300 to 420 nm is 2% or more

(4) Bleed-out resistance Three-layer film obtained by blow-molding (after forming (coating) an antifogging coating film on the inner layer side surface) immediately after film formation and three months after film formation Was measured with a spectrophotometer (U3500, manufactured by Hitachi, Ltd.), and the difference was classified according to the following criteria.
○ ・ ・ Difference in linear light transmittance (%) at 555 nm immediately after film formation and 3 months after film formation is within 5%. × ・ Linear travel at 555 nm immediately after film formation and 3 months after film formation. Difference in light transmittance (%) is greater than 5%

(4) Action suppression test of pests (Onsitsuna lice) In order to confirm the action suppression effects (repellent effect) of Onsitsuna lice under each film spreading condition, using each film created and obtained by the method shown in Table 1, The test using the chamber shown in 3 was carried out.
Table 20 shows the superiority or inferiority of the relative repellent effect of each test group according to the number of heads of the white spotted lice moved to each test section. Since it was thought that the number of heads staying in the test area was less when the white fly was repelled, the determination was made based on which one was repelled.
Of the two test areas, the number of heads was large (low repellent effect): Inferior ×
Of the two test areas, the number of heads was small (high repellent effect): Excellent
Supplement:
・ In this test, the experiment was repeated using another chamber as a repeat test, but the results were similar (repeated test was performed using two chambers to confirm reproducibility).

  [Examples 1 and 2 and Comparative Examples 1 to 3] A three-layer film (anti-fogging coating application type) having ultraviolet transmittance according to the present application was prepared by the formulation described in Table 1, and UV-cutting performance was achieved by the above method. The bleed-out resistance was evaluated. The results are shown in Table 1. The light transmission characteristics of these films are shown in FIG.

  [Examples 1 and 2] FIG. 2 shows a total light transmittance chart obtained by measuring the three-layer film (antifogging coating type) containing the ultraviolet absorbent according to the present application by the above method.

  [Examples 1 and 2 and Comparative Examples 1 to 3] Using a three-layer film (anti-fogging coating coating type) having ultraviolet transmittance according to the present application, an action test for on white lice was conducted by the above method. The results are shown in Table 3.

As is clear from the above results, the films having the light transmittance characteristics according to the present application (Examples 1 and 2) are UV cut films of 400 nm or less described in JP-A-2009-159839, commercially available agricultural films (general Agricultural film that has very good pest repellent performance (behavior control performance of white lice) for type (Comparative Example 3) and UV cut type (Comparative Example 2)) Can be suitably used.
The conventional UV cut film of 380 nm or less UV cut type cannot be said to have sufficient performance in the behavior suppression performance (repellent effect) of white fly, compared with 420 nm or less UV cut type. It turns out that it is inferior.

  In addition, the films having light transmittance characteristics according to the present application (Examples 1 and 2) have good bleed-out resistance with respect to a 400 nm or less UV cut film described in JP-A-2009-159839, and can be used for a long time. It can be seen that the transparency required for the film can be maintained.

  Furthermore, it is preferable to combine the ultraviolet absorbent according to the present application with a triaryltriazine-type ultraviolet absorbent since a small amount of ultraviolet rays can be suppressed as shown in FIG.

  In other words, unless a film containing the ultraviolet absorber of the present invention is used, it is difficult to impart sufficient pest control characteristics as an agricultural film. Reliable crop production such as reduced pesticides becomes possible.

(The invention's effect)
The agricultural film of the present invention is excellent in ultraviolet shielding property (wide absorption wavelength range), excellent in pest control properties and prevention of deterioration of lining materials in the house environment, and excellent in bleed-out resistance. It can be suitably used as an agricultural film. The film of the present invention may be transparent, satin or semi-satin, and can be suitably used for applications of agricultural polyolefin-based films (so-called agricultural poly and the like) for house, tunnel, mulching, bag hanging and the like. .

Claims (7)

Agricultural film characterized by containing a benzotriazole-type ultraviolet absorber represented by the following general formula (1) (R1 and R2 may be the same or different, and each independently has a carbon number of 1 or more. Chain or branched substituents)

  Agricultural film characterized in that at least one of absorption peak wavelengths of benzotriazole type ultraviolet absorber is 360 nm or more Agricultural film comprising a benzotriazole type ultraviolet absorber in which R1 in the general formula (1) is a tBu group and R2 is a Me group

  The agricultural film according to any one of claims 1 to 3, wherein ultraviolet rays of 300 to 420 nm are substantially completely shielded (substantially completely shielded: 1 nm at 300 to 420 nm). (The average value of total light transmittance measured for each is less than 2%) The agricultural film according to any one of claims 1 to 4, further comprising a triaryltriazine-type ultraviolet absorber according to the following general formula (2):

(Wherein R3 to R7 each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.)   The agricultural film according to claim 5, wherein R3 in the formula (2) is a hexyl group, and R4 to R7 are hydrogen atoms.   The agricultural film according to claim 5, wherein R3 in the formula (2) is an octyl group, and R4 to R7 are methyl groups.

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