JP4902193B2 - Polyolefin agricultural film - Google Patents

Description

  The present invention relates to an agricultural film excellent in long-term ultraviolet-cutting durability, long-term weather resistance, durability, and pesticide resistance, and has a function of preventing the length of an insect and controlling a pest for a long time, and after long-term stretching. In addition, there is little decrease in weather resistance under acidic conditions such as acid rain and agricultural chemicals, and when applied with an antifogging coating, it relates to an agricultural film that is excellent in antifogging durability and antifogging coating adhesion. is there.

  In recent years, semi-forcing or suppressing cultivation of agricultural crops to increase their marketability and productivity, agricultural vinyl chloride film (hereinafter referred to as agricultural bi), polyethylene, ethylene-vinyl acetate copolymer, and polyolefin So-called house cultivation and tunnel cultivation are actively carried out to grow useful plants under the covering with agricultural covering materials such as agricultural polyolefin-based resin films (hereinafter referred to as agricultural poly and agricultural vinegar) mainly composed of resin. Yes. Among them, agricultural polyolefin-based resin film mainly composed of polyolefin-based resin is light because its density is smaller than that of vinyl chloride resin, and generates little toxic gas even when incinerated. Wide films that do not require adhesive processing can be provided at low cost, and are being actively used.

  In addition, such an agricultural house is getting larger year by year, and the film expansion work for covering the house with a film requires a lot of manpower. 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. In response to such demands, the film should have a long-term performance that requires various performances such as pest control, easy cultivation, weather resistance, and pesticide resistance, depending on the application. Is done. Among these performances, as one of the techniques that have been considered difficult so far, there is a balanced provision of pest control, length control and pesticide resistance, and many studies have been conducted in the past.

  It is known that by controlling the ultraviolet transmission characteristics of such an agricultural film, it is possible to expect the effect of controlling diseases and insects that occur in the crops in the house, but most of the conventional techniques have an ultraviolet cut characteristic of 380 nm or less. In addition, there is a case where the length of the crop in the house (a phenomenon in which the internode length of the plant becomes long) occurs by cutting the ultraviolet rays to 380 nm, and it is difficult to control the cultivation. On the other hand, it exists as a conventional technique of a film aiming to achieve both a length control effect and a pest control effect by substantially cutting ultraviolet rays at 350 nm or less. For example, an ultraviolet absorber described in JP-B-3-41130 is used. However, the UV cut characteristics could not be maintained for a long period of time, and satisfactory performance could not be maintained with polyolefin-based agricultural films that required long-term stretching.

  In addition, as a method of imparting pesticide resistance to polyolefin films for conventional agricultural applications, a method of combining a hindered amine compound having a general structure and hydrotalcite, or a method of using a weathering agent having a special structure has been proposed. Has been. However, the effect of improving the pesticide resistance is low with the method combined with the heat retention agent, and when it is actually used for agricultural purposes, if the pesticide spraying etc. is performed inside the house, it will cause a drastic decrease in weather resistance, causing a problem in practical use. It was. On the other hand, compounds such as those disclosed in JP-A Nos. 11-80569 and 2001-139821 can improve the pesticide resistance. However, in the case of agricultural films used under harsh conditions, further improvement in pesticide resistance is required, and specific examples of weathering agents and ultraviolet absorbers that can give further improvement and good pesticide resistance. There was a need for a practical combination method.

  By including a specific amount of a triaryltriazine type ultraviolet absorber having a specific structure in a film, the present inventors have better cultivation characteristics (length control effect), pest control effect, and pesticide resistance compared to the previous application. It has been found that sex can be imparted over a long period of time. Furthermore, in the present invention, when an anti-fogging coating film is applied, for example, the adhesion of the anti-fogging coating film under acidic conditions is good, and it is extended outdoors for a long time, including acid rain and agricultural chemicals. Useful as an agricultural film that is often exposed under acidic conditions.

  Therefore, the object of the present invention is to maintain good cultivation characteristics (capacity control effect), good pest control effect, and weather resistance under acidic conditions such as acid rain and agricultural chemicals, and particularly good for a long time. When an anti-fogging coating film is applied to a base film, it is excellent in anti-fogging properties and long-term anti-fog sustainability, and even under acidic conditions such as agricultural chemicals and acid rain. Further, the present invention relates to an agricultural film that exhibits various antifogging properties, paint film adhesion, long-term antifogging properties, weather resistance, and suppresses the bleeding out of the weathering agent and does not deteriorate long-term weatherability. Specifically, when used for agricultural films, it is compatible with easy cultivation (capacity control effect) and pest control effect, agrochemical resistance, durability, antifogging characteristics, long-term antifogging durability, and pesticide resistance. The object is to provide an excellent film for agricultural coating.

  As a result of intensive studies, the inventor has blocked the transmission of ultraviolet light having a wavelength of 350 nm or less to 10% or less, transmits light having a wavelength of 380 to 400 nm on average 50% or more, and has a specific structure. An agricultural film having a specific amount of a triaryltriazine-type ultraviolet absorber having the above-described problems has been found to solve the above problems, and the present invention has been completed.

The present invention has been made on the basis of the above knowledge, and the average transmittance of ultraviolet rays in the wavelength region of 320 to 350 nm is 10% or less, and the average transmittance of light in the wavelength region of 380 to 400 nm is 50% or more. Polyolefin agricultural film comprising a multilayer or a single layer, and having at least one layer comprising a polyolefin resin and at least one triaryltriazine type ultraviolet absorber represented by the following formula (1) It is.
(In formula, R1-R5 represents a hydrogen atom or a C1-C10 alkyl group each independently.)

  The present invention also provides an agricultural film that is particularly excellent in bleed-out resistance and chemical stability when R1 in the formula (1) is a hexyl group and R2 to R5 are hydrogen atoms.

  In addition, the present invention provides an agricultural film particularly excellent in bleed-out resistance and chemical stability when R1 in the formula (1) is an octyl group and R2 to R5 are hydrogen atoms.

  In addition, the present invention has at least one layer containing an ultraviolet absorber component which is a triazine compound having a specific structure according to the present invention, part or all of the components, and a polyolefin resin in a base film A multilayer film for agriculture, comprising a triaryltriazine type ultraviolet absorber represented by the formula (1) based on the total weight of the compound in an amount of more than 0.30% by weight and less than 2.00% by weight. provide

  In addition, the present invention can improve the heat retention by containing at least one infrared absorber in at least one layer of the base film described above, and also exerts an effect on the bleedout suppression of the weather resistance agent. As a result, the adhesion of the coating film after long-term stretching can be improved.

The infrared absorber in the present invention provides an agricultural film that is inexpensive and has good moldability by using an inorganic compound represented by the chemical formula of the following formula description (2).
_{Mg 4.5 Al 2 (OH) 13} CO 3 · 3.5H 2 O (2)

The infrared absorber in the present invention provides an agricultural film that is inexpensive and has good moldability by using an inorganic compound represented by the chemical formula of the following formula description (3).
_{[Al 2 (Li (1-} x) · M (x + y)) (OH) 6 + y] 2 (A n-) 2 (1 + x) / n · mH 2 O (3)
(In the formula, M is Mg and / or Zn, A is an n-valent anion, m is 0 or a positive number, and x and y are in the range of 0 ≦ x <1, 0 ≦ y ≦ 0.5. )

（式中、Ｒ６は、ラジカル、水素原子、メチル基、又は炭素数１以上のメチレン基を含む、官能基もしくは化合物（オリゴマー、ポリマー含む）を表す。） The present invention further includes at least one hindered amine compound having at least two piperidine ring structures represented by the following formula (4) and having a molecular weight of 500 or more in at least one layer of the base film. Provide agricultural film.

(In the formula, R 6 represents a functional group or a compound (including oligomer and polymer) containing a radical, a hydrogen atom, a methyl group, or a methylene group having 1 or more carbon atoms.)

（式中、Ｒ７及びＲ８は、それぞれ独立して水素原子又はメチル基を表し、Ｒ９は水素原子又は炭素数１〜４のアルキル基を表す。） The present invention is excellent in bleed-out resistance by containing a copolymer of ethylene (A) and a cyclic aminovinyl compound (B) represented by the following formula (5) in at least one layer of the base film. In addition, an agricultural film having good long-term weather resistance and good coating film adhesion is provided.

(In the formula, R7 and R8 each independently represent a hydrogen atom or a methyl group, and R9 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.)

  In the copolymer of ethylene (A) and the cyclic aminovinyl compound (B) represented by the above formula (5) in the present invention, R7 and R8 in the above formula (5) are each a methyl group, and R9 is hydrogen. Provided is an agricultural film having excellent bleed-out resistance and long-term weather resistance particularly when it is an atom.

  In the present invention, the average transmittance of ultraviolet rays in the wavelength region of 320 to 350 nm is 10% or less, the average transmittance of light in the wavelength region of 380 to 400 nm is 50% or more, and the general formula (1) By blending a specific amount of a triaryltriazine type UV absorber having the specific structure shown, it is possible to improve cultivation properties (inhibition of length) and to suppress disease and insect damage, and in particular weather resistance under acidic conditions, and an anti-fogging coating film When applied, it can be used to produce agricultural films with excellent long-term anti-fogging sustainability, anti-fogging sustainability under weathering conditions such as agricultural chemicals and acid rain, and weather resistance. (In particular, it has a specific structure and is highly effective) In addition to the above effects, bleed-out to the resin surface is remarkably suppressed, and practical agriculture with excellent anti-fogging durability and long-term weather resistance For fill Found that can be obtained.

  It is known that antifogging coatings, especially agricultural film antifogging coatings with polyolefin resin as the base film, have different performance (particularly coating adhesion) depending on the combination of the antifogging coating and the base film. In Japanese Patent Application No. 11-276093, a hindered amine compound obtained by copolymerizing ethylene and a cyclic aminovinyl compound is contained in a polyolefin film, and a specific antifogging film is formed thereon. As a result, it has been reported that coating film adhesion is improved. That is, the gist of the present invention is that an agricultural polyolefin film (multilayer or single layer) contains at least one hindered amine compound represented by the above formula (4) in at least one layer of the polyolefin multilayer or single layer film. And an agricultural film containing at least one ultraviolet absorber, in particular, an ultraviolet absorber having a specific structure according to the present invention. Here, the layer containing at least one hindered amine compound represented by the formula (4) and the layer containing at least one ultraviolet absorber may be the same or different.

(Embodiment of the Invention)
Hereinafter, the present invention will be described in detail.
Examples of the polyolefin resin used in the present invention include an α-olefin homopolymer, a copolymer of a different monomer mainly containing an α-olefin, an α-olefin and a conjugated diene or a non-conjugated diene, etc. And polyunsaturated compounds, acrylic acid, methacrylic acid, copolymers with vinyl acetate, etc., such as high density, low density or linear low density polyethylene, polypropylene, ethylene-propylene copolymer, ethylene -Butene copolymer, ethylene-4-methyl-1-pentene copolymer, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer and the like. Among these, low density polyethylene having a density of 0.910 to 0.935, an ethylene-α-olefin copolymer, and an ethylene-vinyl acetate copolymer having a vinyl acetate content of 30% by weight or less have transparency and weather resistance. 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. It can be obtained by (Method A) or (Method B).
(Method A) JP-A-58-19309, JP-A-59-95292, JP-A-60-35005, JP-A-60-35006, JP-A-60-35007, JP-A-60-35008 , JP-A-60-35009, JP-A-61-130314, JP-A-3-163088, European Patent Application No. 420436, US Pat. No. 5,555,438 and International Publication WO91. The metallocene catalyst, in particular, the metallocene / alumoxane catalyst, or the metallocene compound disclosed in, for example, International Publication WO92 / 01723, and the metallocene. A catalyst comprising a compound that reacts with a compound to form a stable ion, or further disclosed in JP-A-5-295020 and JP-A-5 Using a catalyst in which a metallocene compound is supported on an inorganic compound as described in No. 295022, etc., the main component ethylene and the secondary component α-olefin having 4 to 20 carbon atoms can be obtained. In this method, copolymerization is performed so that the density of the polymer is 0.880 to 0.930 g / cm 3. Examples of the polymerization method include a high-pressure ion polymerization method, a solution method, a slurry method, and a gas phase method. In these, it is preferable to manufacture by a high pressure ion polymerization method.

The high-pressure ion polymerization method is described in JP-A-56-18607 and JP-A-58-25106, and the pressure is 100 kg / cm 2 or more, preferably 300 to 1500 kg / cm 2. The product is produced by a high pressure ion polymerization method under a reaction condition of a temperature of 125 ° C. or higher, preferably 150 to 200 ° C.
(Method B) Metallocene catalyst component and organoaluminum oxy compound catalyst component described in JP-A-6-9724, JP-A-6-136195, JP-A-6-136196, and JP-A-6-207057 In the presence of an olefin polymerization catalyst, various conditions in the gas phase, slurry, or solution liquid phase, including a particulate carrier, and optionally an organoaluminum compound catalyst component and an ionized ionic compound catalyst component In which ethylene and an α-olefin, specifically an α-olefin having 3 to 20 carbon atoms, are copolymerized so that the density of the resulting copolymer is 0.900 to 0.930 g / cm 3.
A polyolefin resin polymerized by using a metallocene compound, that is, a metallocene polyethylene, is not limited to the above methods (A) and (B) in that good initial transparency and transparency persistence of the film can be obtained. Can be used.

  Polyethylene resins including these metallocene polyethylenes are classified based on temperature rising elution fractionation (TREF), MFR, density, molecular weight distribution, and other various physical properties.

Measurement of elution curve by temperature rising elution fractionation (TREF) The measurement of elution curve by the above temperature rising elution fractionation (TREF) is described in “Journal of Applied Polymer Science. Vol 126, 4, 217-4, 231 ( 1981) ”,“ Polymer debate proceedings 2P1C09 (Showa 63) ”, and the like. That is, first, the target polyethylene is completely dissolved once in a solvent. Thereafter, it is cooled to produce a thin polymer layer on the surface of the inert carrier. Such a polymer layer is formed easily on the inner side (side closer to the surface of the inert carrier), and on the outer side is difficult to crystallize. Next, by elevating the temperature continuously or stepwise, first, at a low temperature, the polymer is eluted from an amorphous portion in the target polymer, that is, from a polymer having a high degree of short-chain branching. As the elution temperature rises, the one with a little branching degree is gradually eluted, and finally the linear part without branching is eluted to complete the measurement. The concentration of the elution component at each temperature is continuously detected, and the composition distribution of the polymer can be measured by the peak of the graph (elution curve) drawn by the elution amount and elution temperature.

The ethylene-α-olefin copolymer used as at least one component of the polyolefin resin of the present invention 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 according to JIS-K7112 is 0.880 to 0.930 g / cm3, preferably 0.880 to 0.920 g / cm3. 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 has a vinyl acetate content in the range of 10 to 25% by weight, preferably in the range of 12 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 the present invention has an average transmittance of ultraviolet rays in the wavelength region of 320 to 350 nm of 10% or less, an average transmittance of light in the wavelength region of 380 to 400 nm is 50% or more, and the above formula A good effect can be obtained when at least one of the triaryltriazine type ultraviolet absorbers represented by (1) is used.

  Particularly preferably, the average transmittance of ultraviolet rays in the wavelength region of 320 to 350 nm is 5% or less, the average transmittance of light in the wavelength region of 380 to 400 nm is 60% or more, and represented by the formula (1). Even better effects can be obtained when at least one of the triaryltriazine type ultraviolet absorbers used is used.

  Here, the light transmittance can be measured using a known spectrophotometer. For measuring light transmittance, when measuring only the straight light component of the light passing through the film (direct light transmittance) and when measuring both the straight light component and the scattered light component (total light transmittance) However, in the present invention, it is preferable to measure the total light transmittance because ultraviolet rays taken into the house as scattered light can also affect the pest control function and the like.

  In the present invention, the average transmittance means an average value of transmittance measured in a corresponding wavelength region. Here, the average value of the transmittance may vary depending on the interval of the wavelength at which the transmittance is measured. In the present invention, preferably, the transmittance is measured every 1 nm in each wavelength region and the measured value is measured. Is the average transmittance.

（式中、Ｒ１〜Ｒ５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。） A particularly effective ultraviolet absorber is a triaryltriazine type ultraviolet absorber represented by the following formula (1).

(In formula, R1-R5 represents a hydrogen atom or a C1-C10 alkyl group each independently.)

  Here, in Formula (1), R1-R5 represents a hydrogen atom or a C1-C10 alkyl group each independently. More preferably, R1 is an alkyl group having 6 to 10 carbon atoms, particularly preferably an alkyl group having 6 to 8 carbon atoms, and R2 to R5 are hydrogen atoms or alkyl groups having 1 to 2 carbon atoms, particularly preferably hydrogen. An atom or a methyl group.

  In the above formula (1), if the number of carbon atoms in R1 is less than the above range, bleeding out tends to occur, which is not preferable, and if it exceeds the above range, weather resistance is inferior. If the number of carbon atoms of R 2 to R 5 is less than the above range, bleeding out tends to occur, which is not preferable, and exceeding the above range is not preferable because weather resistance is poor.

  The method for obtaining the triaryltriazine-based ultraviolet absorber represented by the above formula (1) is not particularly limited, and commercially available products can be used. For example, UV1164 (made by Cytec), TINUVIN 1577 FF (made by Ciba Specialty Chemicals), etc. can be mentioned.

  In the agricultural film of the present invention, the content of the triaryltriazine type ultraviolet absorber represented by the above formula (1) is more than 0.3% by weight and less than 2% by weight with respect to 100% by weight of the polyolefin resin. The amount is preferably 0.31 to 1 part by weight, more preferably 0.33 to 0.9 part by weight. If the content is less than the above range, the effect of improving weather resistance is low, and if it exceeds the above range, there are problems such as a decrease in transparency due to bleeding out.

  From the viewpoint of cost, the triaryltriazine type ultraviolet absorber used in the present invention does not necessarily need to be contained in all layers of the multilayer film, for example, when used in a multilayer film, and is contained in at least one layer. It only has to be. Moreover, this triaryl triazine type | mold ultraviolet absorber can be used in combination with the 1 type, or 2 or more types of other ultraviolet absorber normally used, as long as the said light transmission wavelength is satisfy | filled. Further, one or more commonly used ultraviolet absorbers can be used for the layer not containing the triaryltriazine type ultraviolet absorber. Of course, the triaryltriazine-type ultraviolet absorber may be contained in all layers, but for example, it may be contained in the house intermediate layer, and the other layers may contain an ultraviolet absorber usually blended for agriculture. Moreover, the triaryltriazine type ultraviolet absorber and the ultraviolet absorber usually blended for agricultural use can be contained in the same layer. In that case, it becomes more advantageous in terms of cost than the case of using a triaryltriazine type ultraviolet absorber in all layers.

  The triaryltriazine type ultraviolet absorber used in the present invention is characterized by good bleed-out resistance. However, when added to a multilayer film, the bleed-out resistance can be further improved. . As a method for adding excellent bleed-out resistance, the content of UV absorber X per unit volume in the intermediate layer X> the content Y of UV absorber per unit volume in the inner layer, and X> per unit volume in the outer layer Agricultural multilayer film with UV absorber content Z, agricultural multilayer film in which 80% or more of UV absorber added in all films is contained in the intermediate layer, and other than the surface layer of the multilayer film (house inner layer An agricultural multilayer film obtained by adding a UV absorber to a layer other than the outer layer of the house (intermediate layer).

  Examples of ultraviolet absorbers that are usually blended for agricultural use are 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 5,5′-methylenebis ( 2-hydroxybenzophenones such as 2-hydroxy-4-methoxybenzophenone); 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-dithane) Tributylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-ditert-butylphenyl) -5-chlorobenzotriazole, 2- (2′-hydroxy-3′-tert-butyl-5) '-Methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-5'-tertiary octylpheny 2-benzotriazole, 2- (2′-hydroxy-3′.5′-dicumylphenyl) benzotriazole, 2,2′-methylenebis (4-tert-octyl-6-benzotriazolyl) phenol and the like (2′-hydroxyphenyl) benzotriazoles; phenyl salicylate, resorcinol monobenzoate, 2,4-ditert-butylphenyl-3 ′, 5′-ditert-butyl-4′-hydroxybenzoate, 2,4-di Benzoates such as tert-amylphenyl-3 ′, 5′-ditert-butyl-4′-hydroxybenzoate, hexadecyl-3,5-ditert-butyl-4-hydroxybenzoate; 2-ethyl-2′-ethoxy Substituted oxanilides such as oxanilide and 2-ethoxy-4′-dodecyloxanilide; ethyl-α-cyano-β, β- Cyanoacrylates such as diphenyl acrylate and methyl-2-cyano-3-methyl-3- (p-methoxyphenyl) acrylate; 2- (4,6-diphenyl-1,3,5-triazin-2-yl)- Triazines such as 5-[(hexyl) oxy] -phenol, 2- [4,6-bis (2,4-dimethylphenyl) -1,3,5-triazin-2-yl] -5- (octyloxy) phenol And the like. These ultraviolet absorbers are used alone or in combination of two or more.

  The agricultural film in this invention can provide favorable heat retention by adding an infrared absorber. As the infrared absorber, an inorganic compound (inorganic oxide, inorganic hydroxide, hydrotalcite, etc.) containing at least one atom of Mg, Ca, Al, Si and Li that is effective as a heat retaining agent can be used.

Especially, when the hydrotalcite infrared absorber represented by the following formula (2) is used, a film that is inexpensive and has good moldability can be obtained.
_{Mg 4.5 Al 2 (OH) 13} CO 3 · 3.5H 2 O (2)

In particular, when an infrared absorber represented by the following formula (3) is used, a film that is inexpensive and has good moldability can be obtained.
[Al ₂ (Li _(1-x) · M _{(x + y)} ) (OH) _{6 + y} ] ₂ (A ⁿ⁻ ) _{2 (1 + x) / n} · mH ₂ O (3)
(In the formula, M is Mg and / or Zn, A is an n-valent anion, m is 0 or a positive number, and x and y are in the range of 0 ≦ x <1, 0 ≦ y ≦ 0.5. )

  The method for obtaining the infrared absorber (heat retention agent) represented by the above formula (3) is not particularly limited, and commercially available products can be used. For example, DHT4A (manufactured by Kyowa Chemical Co., Ltd.), HT-P ( Sakai Chemical Co., Ltd.), Optima (Toda Kogyo Co., Ltd.) and Mizukarak (Mizusawa Chemical Co., Ltd.).

  The infrared absorbent (heat retention agent) according to the present invention 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 inorganic compounds containing at least one atom selected from the components: Si, Al, Mg, and Ca can be used. 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 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 surface of the inorganic fine particles is higher fatty acid such as stearic acid, higher fatty acid metal salt such as alkali metal oleate, organic sulfonic acid metal salt such as alkali metal dodecylbenzenesulfonate, higher fatty acid amide, higher fatty acid. Those coated with an ester or wax can also be used.

  The metal composite hydroxide salts 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.

  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.

The agricultural film in the present invention has at least one layer comprising at least one hindered amine compound having at least two piperidine ring structures represented by the following formula (4) and having an average molecular weight of 1000 or more. By having a layer, good weather resistance can be imparted. (In the formula, R 6 represents a functional group or a compound (including oligomer and polymer) containing a radical, a hydrogen atom, a methyl group, or a methylene group having 1 or more carbon atoms.)

  The method for obtaining the hindered amine compound represented by the above formula (4) is not particularly limited, and a commercially available one can be used. For example, TINUVIN NOR 371 (manufactured by Ciba Specialty Chemicals Co., Ltd.), chimassorb 944 (Ciba) -Specialty Chemicals Co., Ltd.), Adeka Stub LA-900 (Asahi Denka Co., Ltd.), etc. are mentioned.

  In the above formula (4), a hindered amine compound having a triazine skeleton and having a molecular weight of 2000 or more (2,2,6,6-tetramethylpiperidine derivative and a mixture thereof) such as TINUVIN NOR 371 (Ciba Specialty Chemicals Co., Ltd.) Manufactured) has a molecular weight similar to that of a hindered amine weathering agent generally used for ordinary agricultural films, and thus can improve the agricultural chemical resistance of the film by the same addition method. However, since it is colored itself, when it is used for an agricultural film that requires high transparency, it is necessary to devise the amount and method of addition. Further, when a high concentration is added to the film surface layer, there is a possibility that troubles may occur in the adhesion of the coating film due to bleeding out.

In the above formula (4), an adduct obtained by adding a compound represented by the following general formula (6) to a polymer having a molecular weight of 300 or more, such as ADK STAB LA-900 (manufactured by Asahi Denka Co., Ltd.), has a high molecular weight. However, since it is difficult to bleed out, the effect of improving weather resistance per added weight is low because it is grafted to a polymer. (In the formula, n represents an integer of 1 to 4, X represents -O- or -NH-, R10 represents a hydrogen atom, an aliphatic acyl group having 1 to 20 carbon atoms, an aliphatic polyvalent acyl group, aromatic Represents an aromatic group or an aromatic polyvalent acyl group.)

  The content of the hindered amine compound represented by the above formula (4) in the resin composition for agricultural film of the present invention is less than 10% by weight, preferably 0.01 to 5% with respect to 100% by weight of the polyolefin resin. % By weight, more preferably 0.1 to 4% by weight. A type grafted onto a polymer such as ADK STAB LA-900 can increase the amount of addition, but since WTUVIN NOR 371 has a molecular weight of 5000 or less, the weathering agent can easily blow out to the film surface due to bleed-out, so a high concentration is added. Is difficult. Therefore, if the content is less than the above range, the effect of improving the weather resistance is low, and if it exceeds the above range, practical use as an agricultural film is caused by bleeding out.

  The hindered amine compound according to the present invention has a molecular weight of 1000 or more, preferably 2000 or more. In order to obtain sufficient bleed-out resistance, 2000 or more is more preferable, and 3000 or more is more preferable.

  From the viewpoint of cost, for example, when the hindered amine compound used in the present invention is used in a multilayer film, it is not necessarily required to be contained in all layers of the multilayer film, and it may be contained in at least one layer. For example, in the case of a multilayer film, the influence on the coating film extends from additives transferred to and transferred from other layers in addition to the additive added to the layer in contact with the coating film. Although a layer or an inner / outer layer is preferable, only an inner layer, only an intermediate layer, only an outer layer, or any combination thereof may be used.

  In addition to the hindered amine compound, it can be used in combination with one or two or more other hindered amine weathering agents that are usually used. Furthermore, the 1 type, or 2 or more types of hindered amine type weathering agent normally used can also be used with respect to the layer which does not contain the said hindered amine compound. Of course, the hindered amine compound may be contained in all layers, but for example, it may be contained in the house intermediate layer, and the other layers may contain hindered amine weathering agents that are usually blended for agricultural use. Moreover, the hindered amine compound and the hindered amine type weathering agent normally mix | blended for agriculture can also be contained in the same layer. In that case, the cost becomes more advantageous than the case where the hindered amine compound is used in all layers.

  The hindered amine weathering agent that is usually blended for agricultural use can have a hindered amine compound (hereinafter referred to as “hindered amine compound”) having at least two piperidine ring structures represented by the formula (4) in the molecule and having a molecular weight of 500 or more. Also referred to as “piperidine ring-containing hindered amine compound”. Here, if the number of piperidine rings of the piperidine ring-containing hindered amine compound is less than 2, sufficient weather resistance cannot be obtained, and if the molecular weight is less than 500, volatilization tends to occur and long-term weather resistance cannot be obtained. 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 that can be used 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) ) Butanetetracarboxylate, 3,9-bis [1,1-dimethyl-2- {tris (2,2,6,6-tetramethyl-4-piperi) Ruoxycarbonyloxy) 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- Tetraazadodecane, 1- (2-hydroxyethyl) -2,2,6,6-tetramethyl-4-piperidinol / dimethyl succinate condensate, 2-tert-octylamino-4,6-dichloro-s- Liazine / N, N′-bis (2,2,6,6-tetramethyl-4-piperidyl) hexamethylenediamine condensate, N, N′-bis (2,2,6,6-tetramethyl-4- Piperidyl) hexamethylenediamine / dibromoethane condensate.

  Examples of commercially available hindered amine compounds that can be used are TINUVIN765, TINUVIN770, TINUVIN780, TINUVIN144, TINUVIN622LD, CHIMASSORB119FL, CHIMASSORB944 (above, manufactured by Ciba Geigy), Sanol LS-765 (manufactured by Sankyo R Co., Ltd., MA, 63) , MARK LA-68, MARK LA-62, MARK LA-67, MARK LA-57 (manufactured by Adeka Argus), CYASORB UV-3346, CYASORB UV-3529, CYASORB UV-3581, CYASORB UV-3853, etc. Is mentioned. These piperidine ring-containing hindered amine compounds are used alone or in combination of two or more.

  In the present invention, an agricultural film having excellent long-term weather resistance and bleed-out resistance can be obtained by using an ethylene / cyclic aminovinyl compound copolymer. The ethylene / cyclic aminovinyl compound copolymer has an effect as a light stabilizer that significantly improves long-term weather resistance as compared with a hindered amine weathering agent used in general agricultural films.

  (3) Ethylene / Cyclic Aminovinyl Compound Copolymer In addition to the triaryltriazine type ultraviolet absorber represented by the above formula (1), the polyolefin resin composition of the present invention further contains ethylene ( A copolymer of A) and a cyclic aminovinyl compound (B) represented by the following formula (5) (hereinafter referred to as “ethylene / cyclic aminovinyl compound copolymer”) may be contained. The ethylene / cyclic aminovinyl compound copolymer is also difficult to bleed out, and by using this in combination with the ultraviolet absorber represented by the above formula (3), extremely high weather resistance is obtained while suppressing bleed out. be able to.

  In said formula (5), R7 and R8 represent a hydrogen atom or a methyl group each independently, and R9 represents a hydrogen atom or a C1-C4 alkyl group. Preferably, R7 and R8 are each a methyl group and R9 is a hydrogen atom.

  The vinyl compound (B) represented by the formula (5) is known and can be synthesized by a known method, for example, a method described in JP-B-47-8539, JP-A-48-65180, or the like. it can.

  Representative examples of the vinyl compound represented by the formula (5) include 4-acryloyloxy-2,2,6,6-tetramethylpiperidine, 4-acryloyloxy-1,2,2,6,6-pentamethyl. Piperidine, 4-acryloyloxy-1-ethyl-2,2,6,6-tetramethylpiperidine, 4-acryloyloxy-1-propyl-2,2,6,6-tetramethylpiperidine, 4-acryloyloxy-1 -Butyl-2,2,6,6-tetramethylpiperidine, 4-methacryloyloxy-2,2,6,6-tetramethylpiperidine, 4-methacryloyloxy-1,2,2,6,6-pentamethylpiperidine 4-methacryloyloxy-1-ethyl-2,2,6,6-tetramethylpiperidine, 4-methacryloyloxy-1-butyl-2, , 6,6-tetramethylpiperidine, 4-crotonoyloxy-2,2,6,6-tetramethylpiperidine, 4-crotonoyloxy-1-propyl-2,2,6,6-tetramethylpiperidine and the like. Can be mentioned.

  As the preferred ethylene / cyclic aminovinyl compound copolymer, the ratio of (B) to the sum of ethylene (A) and cyclic aminovinyl compound (B) is 0.0005 to 0.85 mol%, More preferably, it is 0.001 to 0.55 mol%. That is, the preferred copolymer is one having a high light stability for a low content of the vinyl monomer having a hindered amine group in the side chain (cyclic aminovinyl compound (B)). When the concentration of the cyclic aminovinyl compound (B) is 0.0005 mol%, a sufficient light stabilizing effect is exhibited. On the other hand, when it exceeds 0.85 mol%, it tends to be substantially uneconomical.

  Further, the ethylene / cyclic aminovinyl compound copolymer is such that (B) is not continuous in two or more in the copolymer, and the ratio of being isolated is 83% or more based on the total amount of (B), Preferably it is 90% or more.

  The presence of the cyclic aminovinyl compound (B) is confirmed as follows, as described in JP-A-4-80215. In 13 C-NMR (for example, JNM-GSX270 Spectrometer manufactured by JEOL Ltd.), according to a known method (for example, refer to “Chemistry Dossier (1)” pages 53 to 56 (1985)) Polyethyl acrylate (see Asakura Shoten "Polymer Analysis Handbook", page 969 (1985)) and ethylene-hydroxyethyl acrylate copolymer (Eur. Poly. J. 25, 4, 411-418 (1989) ))), The 32.9 ppm peak in the TMS standard is attributed to the methylene group in the α position from the branch point of the isolated vinyl monomer (B), and the 35.7 ppm peak It was attributed to the methylene group sandwiched between the branch points of the vinyl monomer (B). Using these two signals, the ratio of the vinyl monomer (B) present in isolation in the copolymer of ethylene (A) and vinyl monomer (B) can be calculated by the following formula.

  The proportion of the hindered amine group-containing vinyl monomers having two or more hindered amine groups that are estimated as described above is not continuous but is present in an isolated state of 83% or more based on the total amount of vinyl monomers (B) in the copolymer. Is preferred. If the proportion of vinyl monomers having hindered amine groups in the side chain is less than 83% without two or more vinyl monomers having hindered amine groups in the side chain, the light stability is relatively high In some cases, the feature of having

  The MFR (value measured according to JIS-K6760 (190 ° C., 2.16 kg load)) of the ethylene / cyclic aminovinyl compound copolymer is 0.1 to 200 g / 10 min, preferably 0.5 to 20 g / 10 minutes, more preferably 1-5 g / 10 minutes. When the MFR is less than the above range, the compatibility with the polyolefin resin is poor, and when blended, it causes visible defects in film applications such as fish eyes and boots. On the other hand, if the MFR exceeds the above range, even if the copolymer has a large molecular weight, bleeding or blooming due to diffusion loss occurs, or when it is blended with a polyolefin resin, it causes a decrease in strength of the resulting resin composition. It becomes.

  Further, the ethylene / cyclic aminovinyl compound copolymer is expressed by a ratio of the weight average molecular weight to the number average molecular weight determined by preparing a calibration curve with monodisperse polystyrene using GPC. The value is preferably in the range of 3 to 120. A particularly preferred range is 5-20.

The ethylene / cyclic aminovinyl compound copolymer is produced by subjecting required monomers to copolymerization conditions, but can be produced by a high-pressure low-density polyethylene production apparatus. Usually produced by radical polymerization, the catalyst used is a free radical generator, such as dialkyl peroxides, diacyl peroxides, peroxyesters, ketone peroxides, peroxyketals, hydroperoxides, azo Compounds and the like are useful. As the polymerization apparatus, a continuous stirring tank reactor or a continuous tube reactor generally used in the high-pressure radical polymerization method of ethylene can be used. The polymerization pressure is about 1000 to 5000 kg / cm ² , and the polymerization temperature is about 100 to 400 ° C.

  The content of the ethylene / cyclic aminovinyl compound copolymer in the polyolefin resin composition of the present invention is 2 to 10 parts by weight, preferably 2 to 6 parts by weight with respect to 100 parts by weight of the polyolefin resin. If this content is less than the above range, the weather resistance is inferior because it is inferior.

  From the viewpoint of cost, the ethylene / cyclic aminovinyl compound copolymer used in the present invention is not necessarily contained in all layers of the multilayer film, and may be contained in at least one layer. Further, the ethylene / cyclic aminovinyl compound copolymer can be used in combination with one or two or more hindered amine weathering agents that are usually used. Further, one or two or more hindered amine weathering agents which are usually used can be used for the layer not containing the ethylene / cyclic aminovinyl compound copolymer. Of course, the ethylene / cyclic aminovinyl compound copolymer may be contained in all layers, but it is, for example, contained in the innermost layer and the outermost layer (outer surface of the house), and the other layers are hindered amines usually blended for agricultural use. A light stabilizer can also be contained. Moreover, the hindered amine light stabilizer normally mix | blended for agricultural use can also be contained in the same layer with an ethylene-cyclic amino vinyl compound copolymer. In this case, the cost becomes more advantageous than the case where an ethylene / cyclic aminovinyl compound copolymer is used for all layers.

  The hindered amine light weathering agent normally blended for agricultural use that can be used in combination has a hindered amine compound (hereinafter referred to as “hindered amine compound”) having at least two piperidine ring structures represented by the formula (6) in the molecule and having a molecular weight of 500 or more. It is also referred to as “piperidine ring-containing hindered amine compound”). Here, if the number of piperidine rings of the piperidine ring-containing hindered amine compound is less than 2, sufficient weather resistance cannot be obtained, and if the molecular weight is less than 500, volatilization tends to occur and long-term weather resistance cannot be obtained. 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 that can be used in combination 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) ) Butanetetracarboxylate, 3,9-bis [1,1-dimethyl-2- {tris (2,2,6,6-tetramethyl-4-piperi) Ruoxycarbonyloxy) 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- Tetraazadodecane, 1- (2-hydroxyethyl) -2,2,6,6-tetramethyl-4-piperidinol / dimethyl succinate condensate, 2-tert-octylamino-4,6-dichloro-s- Liazine / N, N′-bis (2,2,6,6-tetramethyl-4-piperidyl) hexamethylenediamine condensate, N, N′-bis (2,2,6,6-tetramethyl-4- Piperidyl) hexamethylenediamine / dibromoethane condensate.

  Examples of commercially available hindered amine compounds that can be used in combination include TINUVIN 770, TINUVIN 780, TINUVIN 144, TINUVIN 622LD, TINUVIN NOR 371, CHIMASSORB 119FL, CHIMASSORB 944 (above, manufactured by Ciba Geigy Corp.), Sanol LS-765 (Sankyo R / K) -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 Corporation) and the like. These piperidine ring-containing hindered amine compounds are used alone or in combination of two or more.

  Content of the said piperidine ring containing hindered amine compound is 0.001-20 weight part with respect to 100 weight part of thermoplastic resins, Preferably it is 0.01-10 weight part. If the content is less than 0.001 part by weight, a sufficient effect cannot be obtained. If the content is more than 20 parts by weight, not only the effect is improved, but also the physical properties of the film are adversely affected.

  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, halogen oxyacid salts, Examples thereof include sulfur-based, phenol-based and phosphite-based antioxidants, heat stabilizers, lubricants, antistatic agents, coloring agents, antiblocking agents, antifogging agents, and antifogging agents.

  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 and 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.

  In addition, as a filler, 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. These fillers may be used alone or in combination of two or more.

  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 preferably in the range of 0.01 to 1 mm, more preferably 0.05 to 0.5 mm, still more preferably 0.05 to 0 in terms of strength and cost. .2 mm. If it is less than this range, there is a problem in strength, and if it exceeds this range, molding is difficult and there is a problem in stretch workability.

  The polyolefin agricultural film of the present invention may be a single layer or multiple layers. In the case of multiple layers, 3 to 5 layers can easily balance each layer. The layer ratio constituting the three-layer film is preferably in the range of 1 / 0.5 / 1 to 1/5/1 in terms of moldability, transparency and strength, and 1/2/1 to 1/4/1. The range of is more preferable. Further, the ratio between the outer layer and the inner layer is not particularly specified, but it is preferable that the ratio is approximately the same because of the curl property of the obtained film.

  The polyolefin agricultural film of the present invention is also characterized in that an antifogging film is formed in contact with the innermost layer of the polyolefin substrate. At this time, when a large amount of an antifogging agent is contained in the film in contact with the antifogging coating film, it is difficult to form the antifogging coating film due to the spraying of the antifogging agent onto the non-uniform film surface. There is. However, when used as a master batch in which various additives are concentrated and blended in advance with the base resin of each layer, the object of the present invention is as an anti-adhesive agent during kneading or as a surface modifier when forming an antifogging film. A small amount can be used as long as it is not impaired.

  The agricultural film of the present invention can form an antifogging coating film and other coating films. For example, the antifogging coating film may be formed in contact with the innermost layer of the polyolefin-based substrate film, and the dust-proof coating film may be in contact with the outermost layer of the polyolefin-based substrate film. In that case, the effect of improving the adhesion of the coating film, which is the effect of the present invention, may be obtained for the dust-proof coating film.

  Examples of the anti-fogging coating film in the present invention include compositions composed mainly of an inorganic colloidal sol such as silica sol and / or alumina sol, and a binder resin such as a thermoplastic resin. 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. Further, the binder resin may not be added, and an inorganic material such as colloidal silica or colloidal alumina may be laminated.

  The inorganic colloidal sol used in the present invention has a function of imparting hydrophilicity to the film surface by coating it on the surface of a hydrophobic polyolefin resin film. As the inorganic colloidal sol, inorganic aqueous colloidal particles such as silica, alumina, water-insoluble lithium silicate, iron hydroxide, tin hydroxide, titanium oxide, barium sulfate were dispersed in water or a hydrophilic medium by various methods. And aqueous sols. Among these, silica sol and alumina sol are preferably used, and these may be used alone or in combination.

As the inorganic colloid sol, it is preferable to select an average particle size in the range of 5 to 100 nm. In this range, two or more colloid sols having different average particle sizes may be used in combination. If the average particle size is too large, the coating may be devitrified in white, and if the average particle size is too small, the stability of the inorganic colloidal sol may be unfavorable.
The amount of the inorganic colloidal sol is preferably 0.2 to 5 and preferably 0.5 to 4 in terms of the weight ratio as the solid content with respect to the total solid weight of the binder resin composition. That is, when the blending amount is too small, a sufficient antifogging effect may not be exhibited. On the other hand, when the blending amount is too large, the antifogging effect is not easily improved in proportion to the blending amount. The film formed later becomes cloudy and causes a phenomenon that the light transmittance of the film is lowered, and the film may be coarse and brittle, which is not preferable.

  Examples of the binder resin include acrylic resins, epoxy resins, urethane resins, polyester resins, and the like, in particular, acrylic resins and / or urethane resins, from the compatibility with the polyolefin base film of the present invention. It is preferable to use a resin, more preferably (a) a hydrophilic acrylic polymer, (c) a hydrophobic acrylic resin, (d) a urethane resin, (e) a hydrophobic acrylic, which will be described later. A resin composed of a polyurethane resin and a polyurethane emulsion are preferred because of their respective characteristics.

  Examples of the acrylic resin include (a) one made of a hydrophilic acrylic polymer, (b) one made of a block copolymer containing a hydrophobic molecular chain block and a hydrophilic molecular chain block in one molecule, (c ) Among those composed of a hydrophobic acrylic resin, (a) is particularly preferable because it is excellent in compatibility with the base film of the present invention in terms of early antifogging wetness, while (c) is preferred. It is excellent in compatibility with the substrate film of the present invention and is preferable.

  As the hydrophilic acrylic polymer (a), a hydroxyl group-containing vinyl monomer component is a main component (preferably 60 wt% to 99.9 wt%, more preferably 65 wt% to 95 wt%), acid Examples thereof include a copolymer containing 0.1 to 30% by weight of a group-containing vinyl monomer component, a partially neutralized product thereof, or a completely neutralized product thereof. Examples of the hydroxyl group-containing vinyl monomer component include hydroxyalkyl (meth) acrylates, such as hydroxymethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2- Hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-hydroxypentyl (meth) acrylate, 6-hydroxyhexyl (meth) An acrylate etc. are mention | raise | lifted. These may be homopolymers, or may be copolymers of these hydroxyalkyl (meth) acrylates as main components and other monomers that can be copolymerized therewith.

  Examples of the acid group-containing monomer copolymerizable with these hydroxyalkyl (meth) acrylates include carboxylic acids, sulfonic acids, and phosphonic acids, and (meth) acrylic acid belonging to carboxylic acids is particularly preferable.

  Examples of other copolymer components include styrene, vinyl terene, vinyl chloride, vinylidene chloride, vinyl oxide, (meth) acrylic acid esters, N, N-dimethylaminoethyl (meth) acrylamide, vinyl pyridine, and the like.

  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.

  As the hydrophobic acrylic resin (c), at least a total of 60% by weight of a monomer comprising an alkyl ester of acrylic acid or methacrylic acid, or a single unit of an alkyl ester of acrylic acid or methacrylic acid and an alkenylbenzene. A monomer mixture and 0 to 40% by weight of a copolymerizable α, β-ethylenically unsaturated monomer are obtained by emulsion polymerization in an aqueous medium, for example, in the presence of an emulsifier, under normal polymerization conditions. And water dispersible polymers or copolymers.

  Examples of alkyl esters of acrylic acid or methacrylic acid used in the production of hydrophobic acrylic resins include acrylic acid methyl ester, acrylic acid ethyl ester, acrylic acid-n-propyl ester, acrylic acid isopropyl ester, acrylic acid-n- Butyl ester, acrylic acid-2-ethylhexyl ester, acrylic acid decyl ester, methacrylic acid methyl ester, methacrylic acid ethyl ester, methacrylic acid-n-propyl ester, methacrylic acid isopropyl ester, methacrylic acid-n-butyl ester, methacrylic acid- 2-ethylhexyl ester, methacrylic acid decyl ester, and the like. Generally, an alkyl alkyl group having 1 to 20 carbon atoms and / or a methyl group having 1 to 20 carbon atoms is used. Acrylic acid alkyl esters are used. Examples of alkenylbenzenes include styrene, α-methylstyrene, vinyltoluene and the like.

  Examples of α, β-ethylenically unsaturated monomers used to obtain hydrophobic acrylic resins include α, β such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, crotonic acid, and itaconic acid. -Ethylenically unsaturated carboxylic acids; α, β-ethylenically unsaturated sulfonic acids such as ethylene sulfonic acid; 2-acrylamido-2-methylpropanoic acid; α, β-ethylenically unsaturated phosphonic acids; acrylic acid or methacrylic acid Hydroxyl group-containing vinyl monomers such as hydroxyethyl; acrylonitriles; acrylic amides; glycidyl esters of acrylic acid or methacrylic acid, and the like. These monomers may be used alone or in combination of two or more, and are preferably used in the range of 0 to 40% by weight. If the amount used is too large, the antifogging performance may be lowered, which is not preferable.

  The acrylic resin is a known emulsifier, for example, an anionic surfactant, a cationic surfactant, or a nonionic surfactant, in the presence of one or more kinds in an aqueous medium. It can be obtained by a method of emulsion polymerization, a method of polymerization using a reactive emulsifier, a method of polymerizing based on an oligo soap theory without containing an emulsifier. In the case of a polymerization method in the presence of an emulsifier, these emulsifiers are used in the range of 0.1 to 10% by weight with respect to the total amount of charged monomers. It is preferable from the viewpoint of stability.

  Examples of the polymerization initiator preferably used for the production of the acrylic resin include persulfates such as ammonium persulfate and potassium persulfate; organic peroxides such as acetyl peroxide and benzoyl peroxide. These can be used in the range of 0.1 to 10% by weight based on the total amount of monomers charged.

  It is particularly preferable to use a hydrophobic acrylic resin having 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 coating.

  The hydrophobic acrylic resin used in the present invention is preferably used as an aqueous emulsion. An aqueous emulsion obtained by polymerization of each monomer in an aqueous medium may be used as it is, or may be diluted by adding a liquid dispersion medium to this, and also produced by the above polymerization. A polymer may be collected separately and re-dispersed in a liquid dispersion medium to form an aqueous emulsion.

  On the other hand, examples of (d) urethane-based resins include polyether-based, polyester-based, and polycarbonate-based anionic polyurethane aqueous compositions and emulsions. The anionic polyurethane emulsion based on polycarbonate is preferable in terms of water resistance and scratch resistance, and silanol in terms of water resistance of the further antifogging coating, improvement in scratch resistance, time to develop antifogging properties and antifogging durability A polycarbonate-based anionic polyurethane emulsion containing a group is more preferred. These may be used alone or in combination of two or more.

  A polycarbonate-based anionic polyurethane emulsion containing a silanol group comprises a polyurethane resin containing at least one silanol group in the molecule and a strongly basic tertiary amine as a curing catalyst. Refers to a colloidal dispersion system (emulsion) in which the silanol group-containing polyurethane resin and the strongly basic tertiary amine are dissolved in the aqueous phase, or a colloidal dispersion system in which fine particles are dispersed.

  Further, as a preferred antifogging film of the present invention, an embodiment using an emulsion prepared by mixing (e) the above-mentioned (c) hydrophobic acrylic resin and (d) an aqueous polyurethane composition is suitable from the viewpoint of compatibility with the substrate. It is preferable from the standpoint of satisfying both the expression speed of fogging and the antifogging sustainability in a well-balanced manner and scratch resistance.

  It is preferable that the amount of the polyurethane aqueous composition is 0.01 or more and 2 or less, more preferably 0.01 or more and 1 or less with respect to the hydrophobic acrylic resin in terms of solid content by weight. When it is less than 0.01, it is difficult to improve the scratch resistance, and it takes a long time until the antifogging property is exhibited, and it is difficult to exhibit a sufficient antifogging effect. In addition, when it is too much, not only the scratch resistance is difficult to improve in proportion to the blending amount, but the coating film formed after coating tends to become cloudy and lower the light transmittance, which is also disadvantageous in terms of cost. It is not preferable.

  When preparing the antifogging agent composition for forming the antifogging film of the present invention, an anionic surfactant, a cationic surfactant, a nonionic surfactant, a polymer surfactant, etc. A surfactant can be added.

  Anionic surfactants include fatty acid salts such as sodium oleate and potassium oleate; higher alcohol sulfates such as sodium lauryl sulfate and ammonium lauryl sulfate; alkylbenzene sulfones such as sodium dodecylbenzenesulfonate and sodium alkylnaphthalenesulfonate Acid salt and alkyl naphthalene sulfonate salt; naphthalene sulfonic acid formalin condensate; dialkyl sulfosuccinate salt; dialkyl phosphate salt; polyoxyethylene sulfate salt such as sodium polyoxyethylene alkyl ether sulfate, sodium polyoxyethylene alkyl phenyl ether sulfate, etc. Can be mentioned.

  Cationic surfactants include: ethanolamines; laurylamine acetate, triethanolamine monostearate formate; amine salts such as stearamide ethyl diethylamine acetate; lauryltrimethylammonium chloride, stearyltrimethylammonium chloride, dilauryldimethyl And quaternary ammonium salts such as ammonium chloride, distearyldimethylammonium chloride, lauryldimethylbenzylammonium chloride, and the like.

  Nonionic surfactants include polyoxyethylene higher alcohol ethers such as polyoxyethylene lauryl alcohol, polyoxyethylene lauryl ether and polyoxyethylene oleyl ether; polyoxyethylene such as polyoxyethylene octylphenol and polyoxyethylene nonylphenol. Alkylaryl ethers; polyoxyethylene acyl esters such as polyethylene glycol monostearate; polypropylene glycol ethylene oxide adducts; sorbitan fatty acid esters such as sorbitan monostearate, sorbitan monopalmitate, sorbitan monobenzoate; diglycerin monopalmi Diglycerol fatty acid esters such as tate and diglycerol monostearate; glycerol monostearate Glycerin fatty acid esters such as pentaerythritol monostearate; pentaerythritol fatty acid esters such as dipentaerythritol monopalmitate; dipentaerythritol fatty acid esters such as dipentaerythritol monopalmitate; sorbitan monopalmitate half adipate, diglycerin monostearate half Sorbitan such as glutamate and diglycerin fatty acid / dibasic acid esters; or condensates thereof with alkylene oxide such as ethylene oxide and propylene on oxide such as polyoxyethylene sorbitan monolaurate and polyoxypropylene sorbitan monostearate Etc .; Polyoxyethylene stearylamine, polyoxyethylene oleylamine, polyoxyethylene stearamide, etc. Carboxymethyl ethylene alkyl amine fatty acid amides; sugar esters.

  Examples of the polymer surfactant include polyacrylate, polymethacrylate, and cellulose ethers.

  By adding these surfactants, the binder resin and the inorganic colloid sol can be easily and quickly uniformly dispersed, and when used in combination with the inorganic colloid sol, hydrophilicity is imparted to the surface of the hydrophobic polyolefin resin film. Fulfills the function of The addition amount of the surfactant is preferably selected in the range of 0.1 to 50 parts by weight with respect to 100 parts by weight of the solid content of the resin. If the amount of the surfactant added is too small, it takes time to sufficiently disperse the resin and the inorganic colloid sol, and the antifogging effect in combination with the inorganic colloid sol cannot be sufficiently exhibited. If the amount added is too large, the transparency of the coating will decrease due to the bleed-out phenomenon on the coating surface formed after coating, and if it is noticeable, it may cause deterioration of the blocking resistance of the coating or decrease the water resistance of the coating. .

  When preparing the anti-fogging agent composition for forming the anti-fogging film of this invention, a crosslinking agent can be added. The crosslinking agent is particularly effective in crosslinking acrylic resins to improve the water resistance of the coating. Examples of the crosslinking agent include phenol resins, amino resins, amine compounds, aziridine compounds, azo compounds, isocyanate compounds, epoxy compounds, silane compounds, etc., but particularly amine compounds and aziridine compounds. Epoxy compounds can be preferably used.

  Examples of amine compounds include aliphatic polyamines such as diethylenetriamine, triethylenepentamine and hexamethylenediamine; alicyclic amines such as 3,3′-dimethyl-4,4′-diaminocyclohexylmethane and isophoronediamine; 4-4 Aromatic amines such as' -diaminodihenylmethane and m-phenylenediamine are used. Examples of the aziridine compounds include tris-2,4,6- (1-aziridinyl) -1,3,5-triazine, trimethylolpropane-tri-β-aziridinylpropionate, tris [1- (2- Methyl) -aziridinyl] phosphine oxide, hexa [1- (2-methyl) -aziridinyl] triphosphatriazine and the like are used.

  Epoxy compounds include reaction products of bisphenol A or bisphenol F and epichlorohydrin, epoxidized novolak resins, epichlorohydrin and aliphatics produced by the reaction of a resin reaction product of phenol (or substituted phenol) and formaldehyde with epichlorohydrin. Resin-like reaction products produced from polyhydric alcohols such as glycerol, 1,4-butanediol, poly (oxypropylene) glycol or similar polyhydric alcohol components, and resins obtained by epoxidation using peracetic acid are used. The Epoxy compounds can be used in combination with tertiary amines or quaternary ammonium salts as catalysts. These crosslinking agents can be used in an amount of 0.1 to 30% by weight based on the acrylic resin solid content.

A liquid dispersion medium can be mix | blended with the anti-fogging agent composition used for this invention as needed. Such a liquid dispersion medium includes a hydrophilic or water-miscible solvent containing water, water; monohydric alcohols such as methyl alcohol, ethyl alcohol, and isopropyl alcohol; polyhydric alcohols such as ethylene glycol, diethylene glycol, and glycerin. Examples: cyclic alcohols such as benzyl alcohol; cellosolve acetates; ketones and the like. These liquid dispersion media may be used alone or in combination.

The anti-fogging agent composition prepared in the present invention is further mixed with conventional additives such as an antifoaming agent, a plasticizer, a film-forming aid, a thickening agent, a pigment, and a pigment dispersant as necessary. be able to. Further, as a binder component other than the acrylic resin, for example, a polyether-based, polycarbonate-based, or polyester-based water-dispersible urethane resin may be mixed.

  In order to form an antifogging film on the surface of a base film, generally a solution or a dispersion of an antifogging composition is respectively applied to a doctor blade coating method, a roll coating method, a dip coating method, a spray coating method, a rod coating method, a bar coating method. A known coating method such as a coating method, a knife coating method, or a brush coating method may be employed and dried after coating. As a drying method after coating, either a natural drying method or a forced drying method may be employed. When the forced drying method is employed, the drying method is usually 50 to 250 ° C., preferably 70 to 200 ° C. Good. For heating and drying, an appropriate method such as a hot air drying method, an infrared drying method, a far infrared drying method, and an ultraviolet curing method may be employed, and it is advantageous to adopt the hot air drying method in consideration of the drying speed and stability. is there.

  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 treatment is performed, and the film surface contains oxygen such as aldehyde, acid, alcohol peroxide, ketone, ether, etc. This is a process for generating a functional group. Sputter etching is a process in which a sample is placed between electrodes 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.

  The agricultural film of the present invention has a good balance between cultivatability (length control) and pest damage control effect, has good weather resistance even under conditions exposed to agricultural chemicals, etc., and maintains its performance for a long period of time. be able to. Furthermore, the antifogging property and its characteristics are maintained over a long period of time, and it is excellent in antifogging property, antifogging film adhesion, and weather resistance even under acidic conditions such as agricultural chemicals and acid rain. It has a good balance of performance for agricultural films. In particular, when the ultraviolet absorber having the structure according to the present invention and / or the ethylene / cyclic aminovinyl compound copolymer according to the present invention is used, the weather resistance, the agricultural chemical resistance, and the bleed out resistance are excellent. The effect of the present invention is particularly exerted, and when an anti-fogging coating film is provided on the film, bleed out is suppressed and adhesion to the substrate is not lowered, which is preferable. The agricultural film of the present invention may be transparent, satin, or semi-pear, and is an agricultural film for house, tunnel, mulching, bag hanging, etc. (so-called agricultural bi, agricultural poly, agricultural sacbi, agricultural PO, hard film) Etc.).

  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. In particular, the anti-fogging coating application type was used this time, but the same effect can be obtained by a method of kneading the anti-fogging agent into the base material.

(1) Preparation of laminated film As a three-layer inflation molding apparatus, a three-layer die using 100 mmφ (manufactured by Plakoken Co., Ltd.), an extruder has two tube inner and outer layers of 30 mmφ (manufactured by Plagiken), intermediate layer Is 40 mmφ (manufactured by Pla Giken Co., Ltd.), outer 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— A three-layer laminated film composed of the components shown in Table-1 to Table-3 was obtained at 7 m / min and a thickness of 0.15 mm. 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] Addition amounts are as described in each table.
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 : Ethylene / vinyl acetate copolymer (vinyl acetate content 5% by weight, MFR 2 g / 10 min)
EVA2. : Ethylene / vinyl acetate copolymer (vinyl acetate content 15% by weight, MFR 2 g / 10 min)
UV absorber A: UV absorber tinuvin 1577FF manufactured by Ciba Specialty Chemicals
It has a triaryltriazine skeleton and has the structure described in the formula (1).
A triaryltriazine compound in which R1 in the formula (1) is a hexyl group and R2 to R5 are hydrogen atoms.
Ultraviolet absorber B: UV absorber made by Cytec Co., Ltd. UV1164
It has a triaryltriazine skeleton and has the structure described in the formula (1).
A triaryltriazine compound in which R1 in the formula (1) is an octyl group and R2 to R5 are methyl groups.
UV absorber C: UV absorber tinuvin PS manufactured by Ciba Specialty Chemicals
It has a benzotriazole skeleton and does not have the structure described in the formula (1).
UV absorber D: UV absorber tinuvin 326 manufactured by Ciba Specialty Chemicals
It has a benzotriazole skeleton and does not have the structure described in the formula (1).
UV absorber E: UV absorber tinuvin 327 manufactured by Ciba Specialty Chemicals
It has a benzotriazole skeleton and does not have the structure described in the formula (1).
Light Stabilizer A: Light Stabilizer Kimasorb 944 manufactured by Ciba Specialty Chemicals
A hindered amine compound of a type in which a hydrogen atom is bonded to a nitrogen atom of a piperidine ring, and has a structure described in the general formula (4). Molecular weight of about 2000 to 3000.
Light Stabilizer B: Cytec Light Stabilizer CYASORB UV-3529
A hindered amine compound in which a methyl group is bonded to the nitrogen atom of the piperidine ring, and has a structure described in the general formula (4). Average molecular weight about 1700.
Light stabilizer C: Light stabilizer “Tinuvin NOR 371 FF” manufactured by Ciba Specialty Chemicals Co., Ltd. 2,2,6,6-tetramethylpiperidine derivative having a triazine skeleton and the structure described in the above general formula (4), molecular weight of about 3600
Light Stabilizer D: Light Stabilizer “Adeka Stub LA-900” manufactured by Asahi Denka Co., Ltd. A hindered amine compound grafted to polyethylene.
It has the structure of the general formula (4).
Ethylene / cyclic aminovinyl copolymer: “NOVATEC LD / XJ100H” manufactured by Nippon Polychem Co., Ltd. MFR = 3 g / 10 min (190 ° C., JIS-K6760) Density = 0.931 g / cm3 (JIS-K6760) Cyclic aminovinyl Compound content = 5.1% by weight (0.7 mol%) Percentage of cyclic aminovinyl compound present in isolation = 90 mol% Melting point = 111 ° C.

Synthetic hydrotalcite A: “DHT4A” manufactured by Kyowa Chemical Co., Ltd. has the structure of the above general formula (2).
Synthetic hydrotalcite B: “HT-P” manufactured by Sakai Chemical Co., Ltd., having the structure of the general formula (2).
Lithium / aluminum composite hydroxide carbonate: “Mizukarak” manufactured by Mizusawa Chemical Co., Ltd., having the structure of the above general formula (3).
Lithium / aluminum / magnesium composite hydroxide condensed silicate: “Optima LS (A)” manufactured by Toda Kogyo Co., Ltd.

(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. ,confirmed.

(3) Formation of antifogging coating film The main component (silica sol and / or alumina sol) shown below, 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: hydrophobic binder resin) 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.M. manufactured by Sanyo Kasei Co., Ltd. A. Z. M: The above antifogging compositions A and B were 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.

  The following physical properties were measured for each type provided with an antifogging coating (film thickness: 150 μm), but the resin, additives, combinations other than the coating used this time, As long as the gist is not changed, the same effect can be obtained. The following tests were conducted for each sample used this time. Each measuring method in an Example and a comparative example is shown below.

1. Total light average transmittance in each wavelength range Total light transmittance in each wavelength range (320 to 350 nm and 380 to 400 nm) is converted into a spectrophotometer (Hitachi, U3500 type) and a 60φ integrating sphere accessory device (UV) (Visible and near infrared region) was attached and measured, and the average value was shown. In addition, an average value is an average value of the transmittance | permeability data for every 1 nm in each wavelength range.

2. UV-blocking durability Laminated film obtained by three-layer inflation molding (in the case of a type where an anti-fogging coating is applied, after forming (coating) an anti-fogging coating on the inner layer side surface), a wavelength of 320 to 350 nm The average transmittance of all the light rays was measured with a spectrophotometer (manufactured by Hitachi, Ltd., U3500 type) in the same manner as 1 above, and the following judgment was made based on the value.
5% or less: ◎
5-10%: ○
10% or more: ×

3. Cultivation (length) test Each film was spread on a pipe house constructed in a field in Matsusaka City, Mie Prefecture. Tomato (House Momotaro) was cultivated inside the house, and the ratio of the average plant height was measured immediately after planting (August 25, 2005) and 30 days after planting.
Criteria for the presence or absence of a chief 1.8 to 1.85: ◎
1.85 to 1.90: ○
1.91 or more: ×
4). Pest damage control test Each film was spread on a pipe house constructed in a field in Matsusaka City, Mie Prefecture. Tomato (House Momotaro) was cultivated inside the house, and the number of whiteflies infestation on the 20th leaf one month after the fixed planting (August 25, 2005) was visually counted.
Judgment criteria for pest control whitefly infestation 0-50: ◎
50-100: ○
100-150: ×

5.5 Tensile rupture strength after lime-sulfur mixture test The film was stretched in a pipe house constructed in a field in Matsusaka City, Mie Prefecture, in a sealed state. Moreover, the commercially available lime sulfur mixture was diluted 10 times in the said pipe house, and the film was sprayed uniformly. The film stretched for about 4 months from mid-April 2005 to mid-August 2005 was exposed to a weather resistance tester (manufactured by The Q-PANEL COMPANY). The tensile strength at break of these films after 1000 hours was measured.
The tensile rupture strength of the films before the treatment was about 55 N in all the films, but after the treatment, the difference in the tensile rupture strength was caused by the difference in the additive composition.
The mechanical strength of each film was determined by measuring the tensile breaking strength in the flow direction (vertical) of the film at a temperature of 23 ° C. according to the measuring method of JIS-K6732.

[Examples 1 to 3, Comparative Examples 1 to 7]
With the above blending, a 150 μm film (antifogging coating application type) was prepared by a processing method. Various tests were carried out under the above conditions using the film obtained here.

[Examples 1 and 2 and Comparative Examples 1 to 3]
By the above blending, a three-layer film having a film thickness of 150 μm and a layer ratio of 1/3/1 (anti-fogging coating application type: UV absorber added) is prepared, and the total light average of 320 to 350 nm and 380 to 400 nm is obtained by the above method. Each film was evaluated by measuring transmittance and conducting a UV cut sustainability test. The results are shown in [Table 1].

[Example 1, Comparative Examples 4 and 5]
By the above blending, a three-layer film having a film thickness of 150 μm and a layer ratio of 1/3/1 (anti-fogging coating application type: UV absorber added) is prepared, and the total light average of 320 to 350 nm and 380 to 400 nm is obtained by the above method. Each film was evaluated by measuring transmittance, cultivating property (length) test, and pest control test. The results are shown in [Table 2].

[Comparative Examples 6, 7, Example 3]
By the above blending, a three-layer film having a film thickness of 150 μm and a layer ratio of 1/3/1 (anti-fogging coating application type: UV absorber added) is prepared, and the total light average of 320 to 350 nm and 380 to 400 nm is obtained by the above method. Each film was evaluated by measuring the transmittance and the tensile rupture strength after the lime-sulfur mixture test. The results are shown in [Table 3].

[Examples 4 to 6]
By the above blending, a three-layer film having a film thickness of 150 μm and a layer ratio of 1/3/1 (anti-fogging coating application type: UV absorber added) is prepared, and the total light average of 320 to 350 nm and 380 to 400 nm is obtained by the above method. Each film was evaluated by measuring the transmittance and the tensile rupture strength after the lime-sulfur mixture test. The results are shown in [Table 4].

  As is clear from the above results, the average transmittance of ultraviolet light in the wavelength region of 320 to 350 nm according to the present invention is 10% or less, and the average transmittance of light in the wavelength region of 380 to 400 nm is 50% or more. A polyolefin agricultural film composed of a multilayer or a single layer having at least one layer containing at least one of a polyolefin resin and a triaryltriazine-type ultraviolet absorber has a length control, pest control, UV cut It is remarkably excellent in sustainability and tensile strength after agrochemical treatment (Examples 1 to 6).

  On the other hand, when used in a type or addition amount other than the ultraviolet absorbent according to the present invention, sufficient ultraviolet cut persistence, length control, pest control, and weather resistance after agrochemical treatment cannot be imparted. . (Comparative Examples 1-5).

(The invention's effect)
The agricultural film of the present invention has good cultivation characteristics (capacity control effect), good pest control effect, and weather resistance under acidic conditions such as acid rain and agricultural chemicals, and is particularly good for a long period of time. When an anti-fogging coating film is applied to a base film, it is excellent in anti-fogging properties and long-term anti-fog sustainability, and even under acidic conditions such as agricultural chemicals and acid rain. Further, the present invention relates to an agricultural film that exhibits various antifogging properties, paint film adhesion, long-term antifogging properties, weather resistance, and suppresses the bleeding out of the weathering agent and does not deteriorate long-term weatherability. Specifically, when used for agricultural films, it is compatible with easy cultivation (capacity control effect) and pest control effect, agrochemical resistance, durability, antifogging characteristics, long-term antifogging durability, and pesticide resistance. To provide an excellent film for agricultural coating
The agricultural film of the present invention may be transparent, satin, or semi-pear, and is an agricultural film for house, tunnel, mulching, bag hanging, etc. (so-called agricultural bi, agricultural poly, agricultural sacbi, agricultural PO, hard film) Etc.).

Claims (11)

  Average transmittance of ultraviolet rays in the wavelength region of 320 to 350 nm is 10% or less, average transmittance of light in the wavelength region of 380 to 400 nm is 60% or more, and polyolefin resin and triaryltriazine type ultraviolet absorption Multilayer having at least one layer containing at least one agent and having a triaryltriazine type ultraviolet absorber content of more than 0.3% and less than 2% by weight with respect to 100% by weight of polyolefin resin Or a polyolefin-based agricultural film comprising a single-layer substrate film (provided that 2- [4,6-bis (2,4-dimethylphenyl) -1,3,5-triazin-2-yl]-in all layers) 5- (Octyloxy) phenol content percentage is excluded except 0.54% by weight). The polyolefin agricultural film according to claim 1, wherein the triaryltriazine type ultraviolet absorber is a triaryltriazine type ultraviolet absorber according to the following general formula (1).

(In formula, R1-R5 represents a hydrogen atom or a C1-C10 alkyl group each independently.)   The agricultural film of Claim 1 or 2 whose R1 in the said Formula (1) is a hexyl group, and R2-R5 is a hydrogen atom.   The agricultural film of Claim 1 or 2 whose R1 in the said Formula (1) is an octyl group, and R2-R5 is a methyl group.   The agricultural film as described in any one of Claims 1 thru | or 4 which contains an at least 1 sort (s) of infrared absorber in at least 1 layer of a base film. The agricultural film according to claim 5, wherein the infrared absorber is an inorganic compound represented by the chemical formula (2) below.
_{Mg 4.5 Al 2 (OH) 13} CO 3 · 3.5H 2 O (2) The agricultural film according to claim 5, wherein the infrared absorber is an inorganic compound represented by the chemical formula (3) below.
[Al ₂ (Li _(1-x) · M _{(x + y)} ) (OH) _{6 + y} ] ₂ (A ⁿ⁻ ) _{2 (1 + x) / n} · mH ₂ O (3)
(In the formula, M is Mg and / or Zn, A is an n-valent anion, m is 0 or a positive number, and x and y are in the range of 0 ≦ x <1, 0 ≦ y ≦ 0.5. ) Any one of hindered amine compounds having at least two piperidine ring structures represented by the following formula (4) and having an average molecular weight of 500 or more are contained in at least one layer of the base film. Agricultural film according to claim 1.

(In the formula, R 6 represents a functional group or a compound (including oligomer and polymer) containing a radical, a hydrogen atom, a methyl group, or a methylene group having 1 or more carbon atoms.) The copolymer of ethylene (A) and the cyclic amino vinyl compound (B) represented by the following formula (5) is contained in at least one layer of the base film. Agricultural film according to claim 1.

(Wherein R7 and R8 each independently represent a hydrogen atom or a methyl group, and R9 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.)   The agricultural film according to claim 9, wherein R7 and R8 in the formula (5) are each a methyl group and R9 is a hydrogen atom.   The agricultural film according to any one of claims 1 to 10, wherein an antifogging coating film is formed on the surface of the innermost layer of the base film.