JP2012044988A - Polyolefin-based agricultural film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyolefin-based agricultural film whose weather resistance can be sustained for a long period of time and which does not generate coloration or odor.SOLUTION: The polyolefin-based agricultural film includes a layer 1 containing a hindered amine compound with a piperidine ring structure expressed in the following formula (1) or (2), and a layer 2 containing a UV absorber.

Description

  The present invention relates to a polyolefin-based agricultural film. More specifically, the present invention relates to a polyolefin-based agricultural film that has long-lasting weather resistance even when exposed to acidic conditions such as acid rain or agricultural chemicals, and does not cause coloring or odor.

Polyolefin-based agricultural films are light and easy to extend, and are therefore widely used in agricultural houses.
The polyolefin-based agricultural film is required to maintain weather resistance for 2 years or more and not to deteriorate in performance due to the applied agricultural chemicals. For example, Patent Document 1 describes a polyolefin-based agricultural film containing a hindered amine compound having at least two triazine skeletons and a specific piperidine ring structure and an ultraviolet absorber for the purpose of improving agricultural chemical resistance.

JP2003-138035

  However, when the polyolefin film for agricultural use described in Patent Document 1 is exposed to acid rain or acidic conditions for long periods of time due to agricultural chemicals, the weather resistance is reduced, or the film has problems of coloring or odor. was there.

  An object of the present invention is to provide a polyolefin-based agricultural film that has long-lasting weather resistance and does not cause coloring or odor.

  As a result of intensive studies, the present inventor has found that the present invention can solve the above problems, and has completed the present invention.

（式中、Ｒ^１は炭素数６０〜１００００００のアルキル基を表す。
Ｒ^１０およびＲ^１１は、互いに独立して、水素原子、ＯＨ、ＯＲ^１５、ＮＲ^１６Ｒ^１７からなる群から選ばれるものであり、Ｒ^１０とＲ^１１は同じであってもよく、異なっていてもよい。
Ｒ^１２は、−ＣＨ_２−、−ＣＯ−、−ＮＲ^１８−からなる群から選ばれるものである。
Ｒ^１３は、−Ｏ−、−ＣＨ_２−、−ＣＯ−、−ＮＲ^１８−からなる群から選ばれるものである。
Ｒ^１４は、１〜５００個の炭素原子及び０〜２００個のヘテロ原子を有する二価有機基であり、Ｒ^１２、Ｒ^１３及び式（２）のピペリジン環構造においてＲ^１２とＲ^１３が結合する第４級炭素原子とともに４、５、６または７員環を形成する二価有機基であり、上記へテロ原子は酸素、窒素、硫黄、リン、ケイ素、ハロゲンからなる群から選ばれる原子である。
Ｒ^１５、Ｒ^１６、Ｒ^１７およびＲ^１８は、水素原子、または１〜５００個の炭素原子および０〜２００個のへテロ原子を有する有機基であり、上記へテロ原子は酸素、窒素、硫黄、リン、ケイ素、ハロゲンからなる群から選ばれる原子であり、Ｒ^１５、Ｒ^１６、Ｒ^１７およびＲ^１８は同じであってもよく、異なっていてもよい。）
本発明の第二は、ポリオレフィン系樹脂と、上記式（１）または上記式（２）で表されるピペリジン環構造を有するヒンダードアミン化合物と、紫外線吸収剤とを含有する層Ａを有するポリオレフィン系農業用フィルムである。 That is, the first of the present invention is a layer 1 containing a polyolefin resin and a hindered amine compound having a piperidine ring structure represented by the following formula (1) or the following formula (2):
A polyolefin agricultural film having a polyolefin resin and a layer 2 containing an ultraviolet absorber.

(In the formula, R ¹ represents an alkyl group having 60 to 1,000,000 carbon atoms.
R ¹⁰ and R ¹¹ are independently selected from the group consisting of a hydrogen atom, OH, OR ¹⁵ , NR ¹⁶ R ¹⁷ , and R ¹⁰ and R ¹¹ may be the same or different. Also good.
R ¹² is selected from the group consisting of —CH ₂ —, —CO—, and —NR ¹⁸ —.
R ¹³ is selected from the group consisting of —O—, —CH ₂ —, —CO—, and —NR ¹⁸ —.
R ¹⁴ is a divalent organic group having 1 to 500 carbon atoms and 0 to 200 heteroatoms, and R ¹² and R ¹³ are bonded to each other in R ¹² , R ¹³ and the piperidine ring structure of the formula (2). A divalent organic group that forms a 4-, 5-, 6-, or 7-membered ring with a quaternary carbon atom, and the heteroatom is an atom selected from the group consisting of oxygen, nitrogen, sulfur, phosphorus, silicon, and halogen is there.
R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ are a hydrogen atom or an organic group having 1 to 500 carbon atoms and 0 to 200 heteroatoms, and the heteroatoms are oxygen, nitrogen, sulfur , Phosphorus, silicon, and halogen, and R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ may be the same or different. )
The second aspect of the present invention is a polyolefin agriculture comprising a layer A containing a polyolefin resin, a hindered amine compound having a piperidine ring structure represented by the above formula (1) or the above formula (2), and an ultraviolet absorber. Film.

  The polyolefin agricultural film of the present invention is an agricultural film that has long-lasting weather resistance and does not cause coloring or odor.

  Examples of the polyolefin resin used in the present invention include α-olefin homopolymers and copolymers.

Examples of the α-olefin include ethylene, propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-decene and the like.
Examples of monomers other than α-olefin copolymerized with α-olefin include polyunsaturated compounds, acrylic acid, methacrylic acid, acrylic acid ester, methacrylic acid ester, and vinyl acetate. Examples of the polyunsaturated compound include conjugated dienes and non-conjugated dienes.

Examples of the α-olefin homopolymer include high-density polyethylene, low-density polyethylene, and polypropylene.
Examples of the α-olefin copolymer include a copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms, an ethylene-vinyl acetate copolymer, and an ethylene-acrylic acid copolymer. Examples of the copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms include an ethylene-propylene copolymer, an ethylene-butene copolymer, and an ethylene-4-methyl-1-pentene copolymer. .

Of these, low density polyethylene having a density of 0.910 to 0.935 g / cm ³ , a copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms, and a vinyl acetate content of 30% by weight or less The ethylene-vinyl acetate copolymer is preferred as an agricultural film from the viewpoint of transparency, weather resistance and price.

  Moreover, in this invention, the copolymer of ethylene and a C3-C20 alpha olefin obtained by copolymerizing with a metallocene catalyst can be used as polyolefin resin. This is what is usually called metallocene polyethylene. Examples of the α-olefin having 3 to 20 carbon atoms copolymerized with ethylene include 1-butene, 1-hexene, 4-methyl-1-pentene, and 1-octene. The above metallocene polyethylene can be obtained by various known production methods described in, for example, JP-A-58-19309 and JP-A-6-9724.

The polyolefin resin used in the present invention preferably exhibits the following physical properties.
Melt flow rate (MFR)
The MFR measured according to JIS-K7210 is 0.01 to 10 g / 10 min, preferably 0.1 to 5 g / 10 min. An MFR of 10 g / 10 min or less is preferred in that the film is difficult to meander during molding and can be stably molded. An MFR of 0.01 g / 10 min or more is preferable in that the resin pressure during molding does not increase, the molding machine is not loaded, and productivity is good.

Density The density measured by JIS-K7112 is 0.880 to 0.930 g / cm ³ , preferably 0.880 to 0.920 g / cm ³ . A density of 0.930 g / cm ³ or less is preferable in terms of high transparency. A density of 0.880 g / cm ³ or more is preferable in that the film surface is not sticky and blocking is unlikely to occur.

Molecular weight distribution The molecular weight distribution (weight average molecular weight / number average molecular weight) obtained by gel permeation chromatography (GPC) is 1.5 to 3.5, preferably 1.5 to 3.0. . A molecular weight distribution of 3.5 or less is preferable in that the mechanical strength is high. A molecular weight distribution of 1.5 or more is preferable in that the film is difficult to meander during molding and can be stably molded.

  The polyolefin agricultural film according to the present invention is a single layer film or a multilayer film. When the polyolefin agricultural film according to the present invention is a multilayer film, 3 to 5 layers are easy to balance each layer. The layer ratio (ratio of thickness of each layer) constituting the three-layer film is preferably in the range of 1 / 0.5 / 1 to 1/5/1 from the viewpoints of moldability, transparency, and strength. The range of 1-1 / 4/1 is more preferable.

  The thickness of the agricultural film of the present invention is preferably 0.01 mm or more from the viewpoint of film strength. Moreover, from the viewpoints of film splicing workability, covering workability during use, and the like, 0.3 mm or less is preferable, and 0.03 mm or more and 0.25 mm or less is more preferable.

The agricultural film according to the present invention includes a polyolefin resin, a layer 1 containing a hindered amine compound having a piperidine ring structure represented by the above formula (1) or the above formula (2), a polyolefin resin, and an ultraviolet absorber. A polyolefin agricultural film having a layer 2 containing
The agricultural film according to the present invention includes a layer A containing a polyolefin resin, a hindered amine compound having a piperidine ring structure represented by the above formula (1) or the above formula (2), and an ultraviolet absorber. A polyolefin-based agricultural film.

  A commercially available thing can be used as a hindered amine compound which has a piperidine ring structure represented by the said Formula (1) or the said Formula (2). For example, Hostavin NOW (manufactured by Clariant Co., Ltd.) can be used. Moreover, these compounds can be manufactured based on the method described in Japanese translations of PCT publication No. 2009-530428.

A hindered amine compound having a piperidine ring structure represented by the above formula (1) or the above formula (2), for example, Hostavin NOW (manufactured by Clariant Co., Ltd.) Without coloring the film by the same addition method as in the above formula (1) or in the formula (2) instead of R ¹ —O—, a compound having a hydrogen atom bonded thereto, and without giving an odor The duration of weather resistance can be lengthened.

  The content of the hindered amine compound having the piperidine ring structure represented by the above formula (1) or the above formula (2) contained in the agricultural film of the present invention is the polyolefin resin contained in the agricultural film according to the present invention. Preferably it is less than 10 weight part with respect to 100 weight part, More preferably, it is 0.01-5 weight part, More preferably, it is 0.1-4 weight part. It is preferable in terms of weather resistance that the content of the hindered amine compound having a piperidine ring structure represented by the above formula (1) or the above formula (2) is 0.01 parts by weight or more. When the amount is 5 parts by weight or less, it is preferable in that the bleed-out of the hindered amine compound is small.

  When the polyolefin agricultural film according to the present invention is a multilayer film, the hindered amine compound having a piperidine ring structure represented by the above formula (1) or the above formula (2) may be contained only in any one layer. , It may be contained in a plurality of layers or in all layers. When the hindered amine compound having the piperidine ring structure represented by the above formula (1) or the above formula (2) is contained in a plurality of layers, for example, it is contained in any combination of the inner layer, the intermediate layer, and the outer layer. It is preferable to be contained in all layers or contained in the inner and outer layers.

  Another hindered amine compound can be contained in the layer containing the hindered amine compound having the piperidine ring structure represented by the above formula (1) or the above formula (2). Moreover, other hindered amine compounds can also be used for the layer not containing the hindered amine compound having the piperidine ring structure represented by the above formula (1) or the above formula (2). The layer contains a hindered amine compound having a piperidine ring structure represented by the above formula (1) or the above formula (2), and the other layer contains a hindered amine compound other than the above formula (1) or the above formula (2). It can also be made.

As a hindered amine compound that can be used in addition to the hindered amine compound having a piperidine ring structure represented by the above formula (1) or the above formula (2), for example, a piperidine ring structure represented by the following formula (9) in the molecule is used. There are hindered amine compounds having at least two and having a molecular weight of 500 or more. When the number of piperidine rings of the hindered amine compound having at least two piperidine ring structures represented by the following formula (9) and having a molecular weight of 500 or more is high, the weather resistance is high and the molecular weight is 500 The above is preferable in that it is less likely to volatilize during molding and the weather resistance lasts for a long time. The number of piperidine rings is preferably 2 to 50, and the molecular weight is preferably 750 or more.

  As the hindered amine compound having at least two piperidine ring structures represented by the above formula (9) and having a molecular weight of 500 or more, for example, bis (1,2,2,6,6-pentamethyl-4-piperidyl) 2-butyl-2- (3,5-ditertiarybutyl-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-piperidyloxycarbonyloxy) 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-tetra Oxaspiro [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-triazine / 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 and the like.

  Commercially available hindered amine compounds that can be used include TINUVIN765, TINUVIN770, TINUVIN780, TINUVIN144, TINUVIN622LD, CHIMASSORB119FL, CHIMASSORB944 (above, manufactured by BASF Japan Ltd.), Sanol LS-765 (manufactured by Sankyo R) 63, MARK LA-68, MARK LA-62, MARK LA-67, MARK LA-57 (above, manufactured by ADEKA CORPORATION), CYASORB UV-3346, CYASORB UV-3529, CYASORB UV-3581, CYASORB UV-3853 Etc. These hindered amine compounds are used alone or in combination of two or more.

（式（３）中、Ｒ^２は炭素数１〜８のアルキル基を表す。）

（式（４）中、Ｒ^３は水素原子、ハロゲン原子、炭素数１〜４のアルキル基もしくはアルコキシル基を表す。Ｒ^４、Ｒ^５は互いに独立して炭素数１〜８のアルキル基もしくはアルコキシル基を表す。）
これらの紫外線吸収剤は、単独で又は二種以上で用いられる。 The agricultural film which concerns on this invention can acquire favorable weather resistance by containing a ultraviolet absorber.
Examples of the ultraviolet absorber include 2-hydroxybenzophenones, 2- (2′-hydroxyphenyl) benzotriazoles, benzoates, substituted oxanilides, cyanoacrylates, and triazines.
Examples of 2-hydroxybenzophenones include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 5,5′-methylenebis (2-hydroxy-4-methoxy). Benzophenone) and the like.
Examples of 2- (2′-hydroxyphenyl) benzotriazoles include 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-ditert-butyl). Phenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-ditert-butylphenyl) -5-chlorobenzotriazole, 2- (2′-hydroxy-3′-tert-butyl-5′-) Methylphenyl) -5-chlorobenzotriazole, 2- (2′-hydroxy-5′-tert-octylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-dicumylphenyl) benzotriazole, 2- (2-hydroxy-3,5-ditertiarypentylphenyl) benzotriazole, 2,2′-methylenebis (4-tertiaryoctyl-6-benzotriazolyl) phenol, 2 -(2-hydroxy-3,5-ditertiarypentylphenyl) benzotriazole and the like.
Examples of benzoates include phenyl salicylate, resorcinol monobenzoate, 2,4-ditert-butylphenyl-3 ′, 5′-ditert-butyl-4′-hydroxybenzoate, 2,4-ditert-amylphenyl-3 Examples include '5'-ditert-butyl-4'-hydroxybenzoate, hexadecyl-3,5-ditert-butyl-4-hydroxybenzoate, and the like.
Examples of substituted oxanilides include 2-ethyl-2′-ethoxyoxanilide, 2-ethoxy-4′-dodecyloxanilide and the like.
Examples of cyanoacrylates include ethyl-α-cyano-β, β-diphenyl acrylate and methyl-2-cyano-3-methyl-3- (p-methoxyphenyl) acrylate.
Triazines include 2- (4,6-diphenyl-1,3,5-triazin-2-yl) -5-[(hexyl) oxy] -phenol, 2- [4,6-bis (2,4 -Dimethylphenyl) -1,3,5-triazin-2-yl] -5- (octyloxy) phenol and the like.
Preferred are benzophenone represented by the following formula (3) and benzotriazole represented by the following formula (4), and more preferred are 2-hydroxy-4-octoxybenzophenone and 2- (2′-hydroxy). -3'-tert-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-3,5-ditert-pentylphenyl) benzotriazole.

(In formula (3), R ² represents an alkyl group having 1 to 8 carbon atoms.)

(In Formula (4), R ³ represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 4 carbon atoms or an alkoxyl group. R ⁴ and R ⁵ are independently of each other an alkyl group or alkoxyl having 1 to 8 carbon atoms. Represents a group.)
These ultraviolet absorbers are used alone or in combination of two or more.

  The content of the ultraviolet absorber contained in the agricultural film according to the present invention is 5 parts by weight or less, preferably 0.001 to 3 parts by weight with respect to 100 parts by weight of the polyolefin resin contained in the agricultural film according to the present invention. More preferably, it is 0.005 to 1 part by weight. When the amount is 5 parts by weight or less of the ultraviolet absorbent, the ultraviolet absorbent is difficult to bleed out, and this is preferable in that the transparency of the agricultural film is not lowered. When the content of the ultraviolet absorber is 0.001 part by weight or more, it is preferable in that the effect of improving weather resistance is high.

When the polyolefin agricultural film is a multilayer film, the ultraviolet absorber may be contained in any one layer, may be contained in a plurality of layers, or may be contained in all layers. When the ultraviolet absorber is contained in a plurality of layers, for example, it is contained in any combination of the inner layer, the intermediate layer, and the outer layer, and is preferably contained in all layers or contained in the inner and outer layers. .
Moreover, you may contain a ultraviolet absorber in the layer which does not contain the hindered amine compound which has the piperidine ring structure represented by the said Formula (1) or the said Formula (2), the said Formula (1) or the said Formula You may contain a ultraviolet absorber in the layer containing the hindered amine compound which has a piperidine ring structure represented by (2). In the present invention, a layer containing a polyolefin resin, a hindered amine compound having a piperidine ring structure represented by the above formula (1) or the above formula (2), and an ultraviolet absorber may be referred to as layer A. .

  The agricultural film which concerns on this invention can provide favorable heat retention property by containing an infrared absorber. As the infrared absorber, an inorganic compound (inorganic oxide, inorganic hydroxide, hydrotalcite, etc.) containing at least one atom of Mg, Al, Si, and Li that is effective as a heat insulating agent can be used. A composite hydroxide containing multimeric oxygen acid ions between layers can also be used.

Examples of the inorganic compound effective as a heat insulating material used in the present invention include hydrotalcite compounds and composite hydroxides.
Specific examples of the hydrotalcite compound include a hydrotalcite compound represented by the following formula (5), natural hydrotalcite, trade name: DHT-4A (manufactured by Kyowa Chemical Industry), Magcrista Synthetic hydrotalcite such as (manufactured by Kyowa Chemical Industry) is mentioned.
_{Mg 4.5 Al 2 (OH) 13} CO 3 · 3.5H 2 O (5)
Examples of the composite hydroxide include lithium aluminum composite hydroxide.

  In addition, the inorganic compound has a surface of higher fatty acid such as stearic acid, higher fatty metal salt such as alkali metal oleate, organic sulfonic acid metal salt such as alkali metal dodecylbenzenesulfonate, higher fatty acid amide. Those coated with higher fatty acid esters or waxes can also be used.

  The said inorganic compound can be used individually or in combination of 2 or more types. The average particle diameter is preferably in the range of 0.05 to 15 μm, more preferably 0.1 to 10 μm. When the average particle size of the inorganic compound is 0.05 μm or more, it is difficult to form a butt (secondary aggregate of inorganic compound), the appearance of the agricultural film is good, and the polyolefin resin and the inorganic compound are kneaded. It is preferable in that it has less dusting and is excellent in handling properties. When the average particle size of the inorganic compound is 15 μm or less, the agricultural film has high transparency, and it is difficult to cause clogging at the breaker screen portion of the extruder when forming the agricultural film, and the productivity is high. preferable.

The composite hydroxide containing multimeric oxygen acid ions between the layers used in the present invention is a composite hydroxide layer as a host layer, and a guest layer composed of multimeric oxygen acid ions, various anions, water, etc. The thing which has the structure laminated | stacked alternately is mentioned. For example, the compound represented by following formula (6) or (7) is mentioned.

[{Mg _y1 M ²⁺ _y2 } _1-x Al _x (OH) ₂ ] ^{x +} · [(A ′) _z1 · (B) _z2 · bH ₂ O] ^x− (6)
(In Formula (6), M ²⁺ represents one or more divalent metal ions selected from the group consisting of Ca, Ni, and Zn. A ′ includes silicon-based, phosphorus-based, and boron-based multimeric oxygen acid ions. Represents one or more multimer oxygenate ions selected from the group, B represents one or more anions other than A ′, and x, y1, y2, z1, z2, and b represent numbers satisfying the following conditions. .
0 <x ≦ 0.5, y1 + y2 = 1, y1 ≦ 1, y2 <1, 0 <z1, 0 ≦ z2,
0 ≦ b <2)

^{_{[{Li y1 G 2+ y2} Al}} 2 (OH) 6 ] ^{x +} · _{[(A ') z1 · (B} ) z2 · bH 2 O ] ^x- (7)
(In Formula (7), G ²⁺ represents one or more divalent metal ions selected from the group consisting of Mg, Ca, Ni, and Zn. A ′ represents a silicon-based, phosphorus-based, boron-based multimeric oxygenate ion. B represents one or more anions other than A ′, and x, y1, y2, z1, z2, and b represent numbers satisfying the following conditions.
0 <y1 ≦ 1, 0 ≦ y2 ≦ 1, 0.5 ≦ (y1 + y2) ≦ 1, x = y1 + 2y2,
0 <z1, 0 ≦ z2, 0 ≦ b <5)

Examples of the composite hydroxide represented by the formula (6) include trade name Magcrista (manufactured by Kyowa Chemical Industry Co., Ltd.).
Moreover, as a composite hydroxide represented by Formula (7), brand name Fujirain (made by Fuji Chemical Industry Co., Ltd.) etc. are mentioned, for example.
In addition, the composite hydroxide of Formula (6) and Formula (7) can be manufactured by the method as described in WO00 / 32515 and WO97 / 00828.

Other infrared absorbers that can be used include, for example, metal oxides, hydroxides, carbonates, sulfates, phosphates, silicates, aluminates, aluminosilicates, viscosity minerals, lithium / aluminum composite hydroxides. , Aluminum / lithium / magnesium composite carbonate compounds, aluminum / lithium / magnesium composite silicate compounds, metal composite hydroxide salts containing plural kinds of anions, and the like.
Examples of the metal oxide include magnesium oxide, calcium oxide, aluminum oxide, silicon oxide, and titanium oxide.
Examples of the hydroxide include lithium hydroxide, magnesium hydroxide, calcium hydroxide, and aluminum hydroxide.
Examples of carbonates include magnesium carbonate and calcium carbonate.
Examples of sulfates include potassium sulfate, magnesium sulfate, calcium sulfate, zinc sulfate, and aluminum sulfate.
Examples of the phosphate include lithium phosphate, sodium phosphate, potassium phosphate, calcium phosphate, and zirconium phosphate (for example, H-type zirconium phosphate disclosed in JP-A-8-67774).
Examples of silicates include magnesium silicate, calcium silicate, aluminum silicate, titanium silicate and the like.
Aluminates include sodium aluminate, potassium aluminate, calcium aluminate and the like.
Examples of aluminosilicates include sodium aluminosilicate, potassium aluminosilicate, and calcium aluminosilicate.
Examples of viscous minerals include kaolin, clay, and talc.
These may be obtained by dehydrating crystal water.

  When the polyolefin agricultural film is a multilayer film, the infrared absorber may be contained only in any one layer or in a plurality of layers. The infrared absorber may be contained in a layer not containing a hindered amine compound having a piperidine ring structure represented by the above formula (1) or the above formula (2), or the above formula (1) or the above formula ( It may be contained in a layer containing a hindered amine compound having a piperidine ring structure represented by 2). Moreover, an infrared absorber may be contained in the layer which does not contain an ultraviolet absorber, and may be contained in the layer containing an ultraviolet absorber. The same layer may contain a polyolefin resin, a hindered amine compound having a piperidine ring structure represented by the above formula (1) or the above formula (2), an ultraviolet absorber, and an infrared absorber.

An agricultural film according to the present invention contains an ethylene / cyclic aminovinyl compound copolymer having a monomer unit based on ethylene and a monomer unit based on a cyclic aminovinyl compound represented by the following formula (8): By doing so, it becomes excellent in long-term weather resistance and bleed-out resistance. The ethylene / cyclic aminovinyl compound copolymer exhibits an effect as a weathering agent that improves long-term weather resistance as compared with a hindered amine compound generally used for agricultural films.

In the above formula (8), R ⁶ and R ⁷ each independently represent a hydrogen atom or a methyl group, and R ⁸ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Preferably, R ⁶ and R ⁷ are each a methyl group, and R ⁸ is a hydrogen atom.

The vinyl compound represented by the formula (8) can be synthesized, for example, by the method described in JP-B-47-8539, JP-A-48-65180, and the like.

  Examples of the vinyl compound represented by the above formula (8) include 4-acryloyloxy-2,2,6,6-tetramethylpiperidine, 4-acryloyloxy-1,2,2,6,6-pentamethylpiperidine, 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-2,2, , 6-tetramethylpiperidine, 4-crotonoyloxy-2,2,6,6-tetramethylpiperidine, 4-crotonoyloxy-1-propyl-2,2,6,6-tetramethylpiperidine, etc. Can do.

  The ethylene / cyclic aminovinyl compound copolymer preferably includes ethylene-based monomer units contained in the ethylene / cyclic aminovinyl compound copolymer and monomer units based on the cyclic aminovinyl compound. The content of monomer units based on the cyclic aminovinyl compound is 0.0005 to 0.85 mol%, more preferably 0.001 to 0.55 mol%, when the sum of the contents of 100 mol% is The thing which is is mentioned. That is, the preferred ethylene / cyclic aminovinyl compound copolymer is one having a high light stability for a low content of vinyl monomer having a hindered amine group in the side chain (cyclic aminovinyl compound). When the concentration of the cyclic aminovinyl compound is 0.0005 mol% or more, the light stabilization effect is exhibited. On the other hand, 0.85 mol% or less is preferable because it is inexpensive.

  The ethylene / cyclic aminovinyl compound copolymer is based on the total amount in which the monomer units based on the cyclic aminovinyl compound are not consecutively present in the copolymer and are present in isolation. It is preferably 83% or more, preferably 90% or more.

  The presence confirmation of the monomer unit based on the cyclic aminovinyl compound is carried out as follows, as described in JP-A-4-80215. In 13C-NMR (for example, JNM-GSX270 Spectrometer manufactured by JEOL Ltd.), according to a known method (for example, refer to Chemical Instrument Dossier (1), pages 53-56 (1985)) Ethyl acrylate (see “Polymer Analysis Handbook”, page 969 (1985) published by Asakura Shoten) and ethylene-hydroxyethyl acrylate copolymer (Eur. Poly. J. 25, No. 4, pages 411 to 418 (1989)) The 32.9 ppm peak in the TMS standard is attributed to the methylene group at the α-position from the branch point of the monomer unit based on the isolated cyclic aminovinyl compound, and the 35.7 ppm peak is By methylene group sandwiched between branch points of monomer units based on two consecutive cyclic aminovinyl compounds Attributed. Using these two signals, the proportion of monomer units based on the cyclic aminovinyl compound in the ethylene / cyclic aminovinyl compound copolymer can be calculated by the following formula.

Ratio of monomer units based on cyclic aminovinyl compound in the ethylene / cyclic aminovinyl compound copolymer in isolation = 32.9 ppm peak area / (32.9 ppm peak area + 35.7 ppm peak area)

  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 minutes, preferably 0.5 to 20 g / 10 minutes, more preferably 1-5 g / 10 minutes. When the MFR of the ethylene / cyclic aminovinyl compound copolymer is 0.1 g / 10 min or more, it is preferable from the viewpoint that visible defects such as fish eyes and butts are unlikely to occur in the agricultural film according to the present invention. When the MFR of the ethylene / cyclic aminovinyl compound copolymer is 200 g / 10 min or less, bleeding of the ethylene / cyclic aminovinyl compound copolymer hardly occurs, and the strength of the agricultural film according to the present invention does not decrease. This is preferable.

  Further, the ethylene / cyclic aminovinyl compound copolymer is a Mw / Mn (Q value) expressed by the ratio between the weight average molecular weight and the number average molecular weight, which was determined by making a calibration curve with monodisperse polystyrene using GPC. ) Is preferably in the range of 3 to 120, more preferably 5 to 20.

  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, based on 100 parts by weight of the polyolefin resin. It is preferable that the content of the ethylene / cyclic aminovinyl compound copolymer is 2 parts by weight or more from the viewpoint of excellent weather resistance. When the content of the ethylene / cyclic aminovinyl compound copolymer is 10 parts by weight or less, it is preferable in that it is inexpensive.

When the polyolefin agricultural film according to the present invention is a multilayer film, the ethylene / cyclic aminovinyl compound copolymer may be contained in any one layer, may be contained in a plurality of layers, or all layers. May be contained. When the ethylene / cyclic aminovinyl compound copolymer is contained in a plurality of layers, for example, it is contained in any combination of an inner layer, an intermediate layer, and an outer layer.
The ethylene / cyclic aminovinyl compound copolymer may be contained in a layer not containing a hindered amine compound having a piperidine ring structure represented by the above formula (1) or the above formula (2). It may be contained in a layer containing a hindered amine compound having a piperidine ring structure represented by 1) or the above formula (2).
The ethylene / cyclic aminovinyl compound copolymer may be contained in a layer that does not contain an ultraviolet absorber, or may be contained in a layer that contains an ultraviolet absorber.
The ethylene / cyclic aminovinyl compound copolymer may be contained in a layer that does not contain an infrared absorber, or may be contained in a layer that contains an infrared absorber.
In addition, the ethylene / cyclic aminovinyl compound copolymer may be contained in, for example, the innermost layer and the outermost layer, and other layers may contain hindered amine compounds other than those represented by formula (1) or formula (2). This layer may contain an ethylene / cyclic aminovinyl compound copolymer and a hindered amine compound other than the formula (1) or the formula (2).

As the polyolefin agricultural film of the present invention, for example, a layer 1 containing a hindered amine compound having a piperidine ring structure represented by the above formula (1) or the above formula (2);
A layer 2 containing a polyolefin-based resin and an ultraviolet absorber;
Layer 3 containing a polyolefin resin and an ethylene / cyclic aminovinyl compound copolymer having a monomer unit based on ethylene and a monomer unit based on a cyclic aminovinyl compound represented by the following formula (8) And
A polyolefin agricultural film containing 2 parts by weight or less of an ultraviolet absorber with respect to 100 parts by weight of the polyolefin resin contained in the film.

  Moreover, in the polyolefin-type agricultural film of this invention, the various additives normally used for a synthetic resin can be used together. Examples of such additives include metal organic acid salts, basic organic acid salts and overbased organic acid salts, epoxy compounds, β-diketone compounds, polyhydric alcohols, halogen oxyacid salts, antioxidants, heat Stabilizers, lubricants, antistatic agents, colorants, antiblocking agents, antifogging agents, antifogging agents, fillers and the like can be mentioned.

The antifogging agent is preferably a polyhydric alcohol partial ester compound composed of a polyhydric alcohol and a higher fatty acid. Examples of the polyhydric alcohol partial ester compound include various known nonionic surfactants, anionic surfactants, and cationic surfactants.
Examples of such an antifogging agent include nonionic surfactants such as sorbitan monostearate, sorbitan monomyristate, sorbitan monopalmitate, sorbitan monobehenate, sorbitan / alkylene glycol condensate and fatty acid ester, etc. Sorbitan surfactants, glycerol monopalmitate, glycerol monostearate, glycerol monolaurate, diglycerol monopalmitate, glycerol dipalmitate, glycerol distearate, diglycerol monopalmitate / monostearate, triglycerol Glycerin surfactants such as monostearate, triglycerin distearate or alkylene oxide adducts thereof, polyethylene glycol monostearate, polyethylene glycol monopar Polyethylene glycol surfactants such as mitates, polyethylene glycol alkylphenyl ethers and other trimethylolpropane surfactants such as trimethylolpropane monostearate, and pentaerythritol interfaces such as pentaerythritol monopalmitate and pentaerythritol monostearate Activator, alkylphenol alkylene oxide adduct; sorbitan / glycerin condensate and fatty acid ester, sorbitan / alkylene glycol condensate and fatty acid ester; diglycerindiolate sodium lauryl sulfate, sodium dodecylbenzenesulfonate, cetyl Trimethylammonium chloride, dodecylamine hydrochloride, lauric acid laurylamide ethyl phosphate, triethyl acetate Le ammonium iodide, oleyl amino diethylamine hydrochloride salts, such as those comprising a 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. 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 be mentioned.

  The content of the fluorine-containing compound having a perfluoroalkyl group contained in the agricultural film according to the present invention is preferably 0.001 to 10 parts by weight, more preferably 0.01 to 100 parts by weight of the polyolefin resin. ~ 5 parts by weight. It is preferable that the content of the fluorine-containing compound is 0.001 to 10 parts by weight in that excellent antifogging properties are exhibited.

  In addition, as a filler, for example, silica, talc, aluminum hydroxide, calcium sulfate, calcium silicate, calcium hydroxide, magnesium hydroxide, kaolin, in order to suppress stickiness of the film or to further improve heat retention 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 antioxidant include phenolic antioxidants, sulfur antioxidants, and phosphite antioxidants.

  Examples of phenolic antioxidants include 2,6-ditert-butyl-p-cresol, 2,6-diphenyl-4-octadecyloxyphenol, stearyl (3,5-ditert-butyl-4-hydroxy). Phenyl) -propionate, distearyl (3,5-ditert-butyl-4-hydroxybenzyl) phosphonate, thiodiethylene glycol bis [(3,5-ditert-butyl-4-hydroxyphenyl) propionate], 1,6- Hexamethylenebis [(3,5-ditert-butyl-4-hydroxyphenyl) propionate], 1,6-hexamethylenebis [(3,5-ditert-butyl-4-hydroxyphenyl) propionic acid amide], 4,4′-thiobis (6-tertiarybutyl-m-cresol), 2,2′-methylenebis (4-methyl-6-tertiary) Tilphenol), 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- Ditert-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 [5.5 ] 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 sulfur-based antioxidants include dialkylthiodipropionates and polyol β-alkyl mercaptopropionic esters.
Dialkyl thiodipropionates include dilauryl thiodipropionate, dimyristyl, distearyl and the like.
Examples of the β-alkyl mercaptopropionic esters of polyols include pentaerythritol tetra (β-dodecyl mercaptopropionate).

  Examples of the phosphite 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 (2,6-ditert-butyl-4-methyl Phenyl) pentaerythritol difo Phyto, tetra (tridecyl) isopropylidene diphenol diphosphite, tetra (C12-15 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-ditertiarybutylphenyl) (octyl) phosphite, tetrakis (2,4-di-t-butylphenyl) 4,4′-biphenylene-di-phosphonite, 2,2-methylenebis (4.6 -Di-t-butylphenyl) 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 polyolefin agricultural film of the present invention may further contain the following components as necessary. Other stabilizers, impact resistance improvers, crosslinking agents, fillers, foaming agents, nucleating agents, plate-out prevention agents, surface treatment agents, flame retardants, fluorescent agents, bactericides, metal deactivators, mold release agents, Examples thereof include pigments and processing aids.

  In order to blend various additives into the agricultural film of the present invention, the required amounts are weighed and blended with a blender such as a ribbon blender, a banbury mixer, a Henschel mixer, a super mixer, a single or twin screw extruder, a roll, and a kneading machine. Use a machine. In order to mold the resin composition thus obtained into a film, for example, a melt extrusion molding method (including T-die method, inflation method, blow molding method), calendar molding method, roll molding method, melt casting Methods such as a molding method, a pressure molding method, a paste molding method, and a powder molding method can be suitably used.

  The example of preferable embodiment of the agricultural film of this invention is a film which has the layer of the anti-fogging film | membrane which comprises the one surface. Examples of the antifogging film include a coating film of an inorganic oxide sol and a coating film made of an inorganic oxide and an organic compound. Examples of the inorganic oxide sol include colloidal silica and alumina sol, and examples of the organic compound include polymer resin binders such as acrylic resins, polyester resins, and polyurethane resins, and surfactants. The anti-fogging coating may be formed on one side of the agricultural film, or may be formed on each of both sides of the agricultural film. The antifogging film may be a single layer film or a multilayer film having two or more layers. The method of laminating the antifogging film on the agricultural film may be a method by coating, or a method of laminating a previously produced antifogging film on the agricultural film.

  The polyolefin agricultural film according to the present invention can be used as an agricultural film such as a greenhouse covering film.

Claims (7)

A layer 1 containing a polyolefin-based resin and a hindered amine compound having a piperidine ring structure represented by the following formula (1) or the following formula (2);
A polyolefin agricultural film having a polyolefin resin and a layer 2 containing an ultraviolet absorber.

(In the formula, R ¹ represents an alkyl group having 60 to 1,000,000 carbon atoms.
R ¹⁰ and R ¹¹ are independently selected from the group consisting of a hydrogen atom, OH, OR ¹⁵ , NR ¹⁶ R ¹⁷ , and R ¹⁰ and R ¹¹ may be the same or different. Also good.
R ¹² is selected from the group consisting of —CH ₂ —, —CO—, and —NR ¹⁸ —.
R ¹³ is selected from the group consisting of —O—, —CH ₂ —, —CO—, and —NR ¹⁸ —.
R ¹⁴ is a divalent organic group having 1 to 500 carbon atoms and 0 to 200 heteroatoms, and R ¹² and R ¹³ are bonded to each other in R ¹² , R ¹³ and the piperidine ring structure of the formula (2). A divalent organic group that forms a 4-, 5-, 6-, or 7-membered ring with a quaternary carbon atom, and the heteroatom is an atom selected from the group consisting of oxygen, nitrogen, sulfur, phosphorus, silicon, and halogen is there.
R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ are a hydrogen atom or an organic group having 1 to 500 carbon atoms and 0 to 200 heteroatoms, and the heteroatoms are oxygen, nitrogen, sulfur , Phosphorus, silicon, and halogen, and R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ may be the same or different. ) A polyolefin agricultural film having a layer A containing a polyolefin resin, a hindered amine compound having a piperidine ring structure represented by the following formula (1) or (2), and an ultraviolet absorber.

(In the formula, R ¹ represents an alkyl group having 60 to 1,000,000 carbon atoms.
R ¹⁰ and R ¹¹ are independently selected from the group consisting of a hydrogen atom, OH, OR ¹⁵ , NR ¹⁶ R ¹⁷ , and R ¹⁰ and R ¹¹ may be the same or different. Also good.
R ¹² is selected from the group consisting of —CH ₂ —, —CO—, and —NR ¹⁸ —.
R ¹³ is selected from the group consisting of —O—, —CH ₂ —, —CO—, and —NR ¹⁸ —.
R ¹⁴ is a divalent organic group having 1 to 500 carbon atoms and 0 to 200 heteroatoms, and R ¹² and R ¹³ are bonded to each other in R ¹² , R ¹³ and the piperidine ring structure of the formula (2). A divalent organic group that forms a 4-, 5-, 6-, or 7-membered ring with a quaternary carbon atom, and the heteroatom is an atom selected from the group consisting of oxygen, nitrogen, sulfur, phosphorus, silicon, and halogen is there.
R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ are a hydrogen atom or an organic group having 1 to 500 carbon atoms and 0 to 200 heteroatoms, and the heteroatoms are oxygen, nitrogen, sulfur , Phosphorus, silicon, and halogen, and R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ may be the same or different. ) The polyolefin agricultural film according to claim 1 or 2, wherein the ultraviolet absorber is a benzophenone type ultraviolet absorber represented by the following formula (3).

(In the formula, R ² represents an alkyl group having 1 to 8 carbon atoms.) The polyolefin agricultural film according to claim 1 or 2, wherein the ultraviolet absorber is a benzotriazole type ultraviolet absorber represented by the following formula (4).

(In the formula, R ³ represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 4 carbon atoms or an alkoxyl group. R ⁴ and R ⁵ each independently represent an alkyl group having 1 to 8 carbon atoms or an alkoxyl group. .) A composite containing a hydrotalcite compound represented by the following formula (5) or a multimeric oxygen acid ion represented by the following formula (6) or the following formula (7) in at least one layer of the polyolefin-based agricultural film The polyolefin agricultural film according to any one of claims 1 to 4, comprising an infrared absorber which is a hydroxide.
Mg _4.5 Al ₂ (OH) ₁₃ CO ₃ .3.5H ₂ O (5)
[{Mg _y1 M ²⁺ _y2 } _1-x Al _x (OH) ₂ ] ^{x +} · [(A ′) _z1 · (B) _z2 · bH ₂ O] ^x− (6)
( ^Wherein M ²⁺ represents one or more divalent metal ions selected from the group consisting of Ca, Ni and Zn. A ′ is selected from the group consisting of silicon-based, phosphorus-based, and boron-based multimeric oxygen acid ions. And B represents one or more anions other than A ′, and x, y1, y2, z1, z2, and b represent numbers satisfying the following conditions.
0 <x ≦ 0.5, y1 + y2 = 1, y1 ≦ 1, y2 <1, 0 <z1, 0 ≦ z2,
0 ≦ b <2)
_{^{[{Li y1 G 2+ y2} Al}} 2 (OH) 6 ] ^{x +} · _{[(A ') z1 · (B} ) z2 · bH 2 O ] ^x- (7)
(In the formula, G ²⁺ represents one or more divalent metal ions selected from the group consisting of Mg, Ca, Ni and Zn. A ′ is a group consisting of silicon-based, phosphorus-based, and boron-based multimeric oxygen acid ions. B represents one or more anions other than A ′, and x, y1, y2, z1, z2, and b represent numbers satisfying the following conditions.
0 <y1 ≦ 1, 0 ≦ y2 ≦ 1, 0.5 ≦ (y1 + y2) ≦ 1, x = y1 + 2y2,
0 <z1, 0 ≦ z2, 0 ≦ b <5) Ethylene / cyclic aminovinyl compound copolymer having a monomer unit based on ethylene and a monomer unit based on a cyclic aminovinyl compound represented by the following formula (8) on at least one layer of the polyolefin agricultural film The polyolefin agricultural film according to any one of claims 1 to 5, comprising:

(In the formula, R ⁶ and R ⁷ each independently represent a hydrogen atom or a methyl group, and R ⁸ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.) The polyolefin agricultural film contains a layer 1 containing a hindered amine compound having a piperidine ring structure represented by the following formula (1) or the following formula (2):
A layer 2 containing a polyolefin-based resin and an ultraviolet absorber;
Layer 3 containing a polyolefin resin and an ethylene / cyclic aminovinyl compound copolymer having a monomer unit based on ethylene and a monomer unit based on a cyclic aminovinyl compound represented by the following formula (8) And
A polyolefin agricultural film containing 2 parts by weight or less of an ultraviolet absorber with respect to 100 parts by weight of a polyolefin resin contained in the film.

(In the formula, R ¹ represents an alkyl group having 60 to 1,000,000 carbon atoms.
R ¹⁰ and R ¹¹ are independently selected from the group consisting of a hydrogen atom, OH, OR ¹⁵ , NR ¹⁶ R ¹⁷ , and R ¹⁰ and R ¹¹ may be the same or different. Also good.
R ¹² is selected from the group consisting of —CH ₂ —, —CO—, and —NR ¹⁸ —.
R ¹³ is selected from the group consisting of —O—, —CH ₂ —, —CO—, and —NR ¹⁸ —.
R ¹⁴ is a divalent organic group having 1 to 500 carbon atoms and 0 to 200 heteroatoms, and R ¹² and R ¹³ are bonded to each other in R ¹² , R ¹³ and the piperidine ring structure of the formula (2). A divalent organic group that forms a 4-, 5-, 6-, or 7-membered ring with a quaternary carbon atom, and the heteroatom is an atom selected from the group consisting of oxygen, nitrogen, sulfur, phosphorus, silicon, and halogen is there.
R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ are a hydrogen atom or an organic group having 1 to 500 carbon atoms and 0 to 200 heteroatoms, and the heteroatoms are oxygen, nitrogen, sulfur , Phosphorus, silicon, and halogen, and R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ may be the same or different. )

(In the formula, R ⁶ and R ⁷ each independently represent a hydrogen atom or a methyl group, and R ⁸ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.)