JP2001200069A - Polyolefin resin film - Google Patents

Abstract

(57) Abstract: A polyolefin that suppresses the occurrence of film whitening due to bleeding of a surfactant (antifogging agent) on the surface and is excellent in antifogging properties, especially at initial or low temperature. To provide a base resin film. A film comprising a polyolefin-based resin, wherein at least one surface layer of the film has a thickness of 0.5
Content of surfactant (B) containing ３3% by weight of HLB having a surfactant of 12 or more (A) and 0.2-3% by weight of HLB having a surfactant of less than 12 (B) [B]
(A) Content of surfactant (A) based on (% by weight)
A polyolefin-based resin film, wherein the ratio (A) / [B] of (% by weight) satisfies the following formula (1). 1 ≦ [A] / [B] ≦ 5 (1)

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a polyolefin resin film having good antifogging properties.

[0002]

2. Description of the Related Art Conventionally, as a covering film for a house or a tunnel (hereinafter collectively referred to as an agricultural house) in greenhouse horticulture, a polyvinyl chloride film or a polyolefin resin film (for example, a polyethylene film or ethylene / vinyl acetate) is used. Copolymer film) is mainly used. Important properties of the film used for the above-mentioned applications include anti-fogging property as well as transparency, heat retention and weather resistance. The anti-fogging property is a property of preventing water vapor evaporating from soil or crops in an agricultural house from condensing on the surface of the coating film to form water droplets and clouding the coating film.

As an antifogging resin film, Japanese Patent Application Laid-Open No.
Japanese Patent No. 9046 discloses a film containing a sorbitan-based or glycerin-based surfactant.
No. 120866 discloses a film containing a polyoxyethylene alkylamine-based surfactant.
However, in these films, the film is whitened due to bleeding of the surfactant on the film surface,
There is a problem that the antifogging property, especially the initial or low temperature antifogging property is insufficiently developed.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to suppress the occurrence of whitening of a film due to the bleeding of a surfactant (anti-fogging agent) on the surface and to prevent the occurrence of anti-fogging property, especially at an early stage or at a low temperature. An object of the present invention is to provide a polyolefin resin film having excellent haze.

[0005]

Means for Solving the Problems The present inventors diligently studied in order to solve the above-mentioned problems, and formed two or more surfactants having HLBs in specific ranges different from each other into a film at a specific weight ratio. It has been found that the above objects can be achieved by blending, and the present invention has been completed. That is, the present invention relates to a film comprising a polyolefin-based resin, wherein at least one surface layer of the film has a H content of 0.5 to 3% by weight.
Surfactant (A) having an LB of 12 or more and 0.2 to 3% by weight
Contains a surfactant (B) having an HLB of less than 12, and the content of the surfactant (A) [A] (% by weight) relative to the content of the surfactant (B) [B] (% by weight) Ratio [A] /
Provided is a polyolefin-based resin film, wherein [B] satisfies the following formula (1). 1 ≦ [A] / [B] ≦ 5 (1) In the polyolefin-based resin film having the above-described structure, the occurrence of whitening of the film due to bleeding of a surfactant (anti-fogging agent) on the surface is suppressed, and the film is prevented. Excellent fogging properties, especially antifogging properties at initial or low temperature.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION As the polyolefin resin constituting the film of the present invention, a homopolymer of α-olefin such as polyethylene and polypropylene, an ethylene / propylene copolymer, an ethylene / butene-1 copolymer, Ethylene / 4-methyl-1-pentene copolymer, ethylene / hexene-1 copolymer, ethylene / octene-
Ethylene / α-olefin copolymer such as 1 copolymer, ethylene / vinyl acetate copolymer, ethylene / acrylic acid copolymer, ethylene / methyl methacrylate, ethylene / vinyl acetate / methyl methacrylate copolymer, Copolymers with different monomers having an α-olefin as a main component such as an ionomer resin may be used. From the viewpoints of film transparency, weather resistance and production cost, polyethylene, ethylene / α-olefin copolymer and vinyl acetate
0% by weight or less of an ethylene / vinyl acetate copolymer is preferred. The film of the present invention can have a multilayer structure as described later, but the polyolefin resins constituting each layer of the multilayer film may be the same or different.

[0007] The method for producing the polyolefin resin is not particularly limited. For example, as a method for producing an ethylene / α-olefin copolymer, ethylene and an α-olefin are prepared by using a so-called single-site catalyst such as a transition metal complex catalyst such as palladium or nickel or a metallocene catalyst in the presence of a solvent. Alternatively, a method in which polymerization is carried out in a gas phase / solid phase, a liquid phase / solid phase, or a homogeneous liquid phase in the absence of the polymer may be used. The polymerization temperature is usually from 30 ° C. to 300 ° C., and the polymerization pressure is usually from about atmospheric pressure to 3000 kg / cm ² . For example, JP-A-6-9724, JP-A-6-136195, JP-A-6-136196, JP-A-6-20
An ethylene / α-olefin copolymer can be produced by copolymerizing ethylene and an α-olefin in the presence of a so-called metallocene-based catalyst containing a metallocene catalyst component described in, for example, Japanese Patent No. 7057. .

[0008] The surfactant (A) contained in the polyolefin resin film of the present invention has an HLB of 12 or more, and the HLB of the surfactant (A) is preferably 1
It is 2 or more and 18 or less. The surfactant (A) is usually selected from among anionic surfactants, cationic surfactants, amphoteric surfactants and nonionic surfactants, and may be selected from among, for example, thermal stability during film production. From the viewpoint, a nonionic surfactant is preferable.

Specific examples of the nonionic surfactant corresponding to the surfactant (A) include polyoxyethylene (2)
0) Sorbitan monolaurate, polyoxyethylene (20) sorbitan monopalmitate, polyoxyethylene (20) sorbitan monostearate, polyoxyethylene (20) sorbitan monooleate, polyoxyethylene (20) sorbitan monobehenate, etc. Polyoxyethylene sorbitan fatty acid esters; polyoxyethylene (20) glycerin monolaurate, polyoxyethylene (20) glycerin monostearate, polyoxyethylene (20) glycerin monooleate, and other polyoxyethylene glycerin fatty acid esters; Ethylene (20) diglycerin monostearate,
Polyoxyethylene polyglycerin fatty acid esters such as polyoxyethylene (20) diglycerin monobehenate; polyglycerin fatty acid esters such as decaglycerin monostearate and decaglycerin monobehenate; polyoxyethylene (20) laurylamine, polyoxy Polyoxyethylene alkylamines such as ethylene (20) stearylamine, polyoxyethylene (20) laurylamine monolaurate and fatty acid esters thereof; polyoxyethylene (20) stearyl ether, polyoxyethylene (20) oleyl ether, etc. Oxyethylene alkyl ether; polyoxyethylene alkyl aryl ether such as polyoxyethylene (20) nonylphenyl ether, polyethylene glycol (# 800 Monolaurate, polyethylene glycol (# 800) monostearate, polyethylene glycol fatty acid esters such as polyethylene glycol (# 800) distearate and the like. Preferably, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene glycerin fatty acid ester, polyoxyethylene alkylamine and its fatty acid ester, and polyglycerin fatty acid ester are used. In the above compounds, for example, polyoxyethylene (20) sorbitan monolaurate means an ethylene oxide adduct of sorbitan monolaurate and has 20 ethylene oxide groups per molecule. In addition, polyethylene glycol (# 800) monolaurate means a monoester composed of polyethylene glycol having a molecular weight of 800 and lauric acid. When the surfactant (A) is an ethylene oxide adduct, the number of ethylene oxide groups per molecule is 10 to 2
It is preferable that the number is 5 in terms of good antifogging property, versatility, and price.

The surfactant (B) contained in the polyolefin resin film of the present invention has an HLB of less than 12. The surfactant (B) is usually selected from an anionic surfactant, a cationic surfactant, an amphoteric surfactant and a nonionic surfactant, but from the viewpoint of thermal stability during film production and the like. Nonionic surfactants are preferred.

[0011] The polyolefin resin film of the present invention can be used as the surfactant (B) as HL having relatively strong hydrophilicity.
It is preferable that the surfactant (B) having B of 6 or more and less than 12 and the surfactant (D) of HLB having relatively high hydrophobicity of 2 or more and less than 6 are also contained.

Specific examples of the nonionic surfactant corresponding to the surfactant (C) include sorbitan fatty acid esters such as sorbitan monolaurate and sorbitan monostearate; polyoxyethylene (1) sorbitan monostearate Polyoxyethylene sorbitan fatty acid esters such as polyoxyethylene (3) sorbitan tristearate; polyoxyethylene glycerin fatty acid esters such as polyoxyethylene (3) glycerin monostearate and polyoxyethylene (3) glycerin monooleate; Polyoxyethylene polyglycerin fatty acid esters such as glycerin monolaurate, polyoxyethylene (1) diglycerin monostearate, polyoxyethylene (3) diglycerin sesquistearate; tetraglyceride Fatty acid esters of polyglycerol such as monostearate, hexaglycerin distearate and tetraglycerin monobehenate; polyoxyethylene (4) stearylamine, polyoxyethylene (4) oleylamine, polyoxyethylene (10) stearylamine monostearate Polyoxyethylene alkylamines and fatty acid esters thereof; polyoxyethylene (4) stearyl ether, polyoxyethylene (4) polyoxyethylene alkyl ethers such as oleyl ether; polyoxyethylene (4) nonyl phenyl ether and other polyoxyethylene alkylamines Oxyethylene alkyl aryl ethers and the like can be mentioned.

Specific examples of the nonionic surfactant corresponding to the surfactant (D) having an HLB of 2 or more and less than 6 include sorbitan distearate, sorbitan monomontanate, polyoxypropylene (1) sorbitan Sorbitan fatty acid esters such as dipalmitate; glycerin fatty acid esters such as glycerin monopalmitate and glycerin monostearate; polyoxyethylene glycerin fatty acid esters such as polyoxyethylene (1) diglycerindiolate; diglycerin distearate, tetra Polyglycerin fatty acid esters such as glycerin tristearate, hexaglycerin dibehenate and tetraglycerin triolate; (Examples of free amines) polyoxyethylene (2) octacosylamine, polyoxyethylene (2 ) Polyoxyethylene alkylamines such as stearylamine monostearate, polyoxyethylene (4) stearylamine monostearate, polyoxyethylene (2) laurylamine stearate, polyoxyethylene (4) stearylamine monooleate and fatty acids thereof Esters: polyoxyethylene (2) stearyl ether, polyoxyethylene (2)
Polyoxyethylene alkyl ethers such as oleyl ether; polyoxyethylene alkyl aryl ethers such as polyoxyethylene (2) nonylphenyl ether;

In the present invention, the HLB of the surfactant is determined as follows. [I] The HLB of polyhydric alcohol fatty acid esters such as glycerin fatty acid esters and sorbitan fatty acid esters and the ethylene oxide adduct thereof is as follows: Griffin
Is determined using the following equation. HLB = 20 (1-S / A) Here, S represents the saponification value of the polyhydric alcohol fatty acid ester, and A represents the acid value of the raw material fatty acid. For details, the following documents can be referred to. Reference 1: WC
Griffin, J. Soc. Cosmetic Chemists., 1, 311 (1949); Reference 2: Yoshiro Ishii, Nonionic surfactant, Seibundo Shinkosha (195
9) Page 137 [II] The HLB of an amine surfactant such as polyoxyethylene alkylamine and its fatty acid ester is determined using the following formula proposed by Oda. HLB = {inorganic /} organic × 10 Here, organic is the number of carbon atoms in the compound × 20, and inorganic is a numerical value determined for each type of bond in the compound,
For example, 100 for -OH, 70 for -NR _2, for -COOR 60, for -O- 7
5 For details, the following documents can be referred to. Reference 3: Oda, Teijin Times, 22, No. 9 (195
2); Reference 4: Oda, Teramura, Synthesis of Surfactants and Their Applications,
Maki Shoten (1957), p. 502 [III] The HLB of an ethylene oxide adduct of polyethylene glycol fatty acid ester, polyoxyethylene alkyl ether, or polyoxyethylene alkyl allyl ether is determined using the following formula. HLB = E / 5 where E is the weight fraction (%) of oxyethylene groups.
For details, reference can be made to Reference 4 described above. [IV] HLB of other nonionic surfactants, cationic and anionic surfactants, and amphoteric surfactants is Da
Determined using the following formula proposed by vis: HLB = Σ (number of hydrophilic groups) −n + 7 where n is the number of methylene groups (CH ₂ ). For details, the following documents can be referred to. Reference 5: JTDavies, Proc.2nd.Intern.Congress of Surface
Activity, 1,426 (1957); Reference 6; Takahashi, Namba, Koike,
Kobayashi, Handbook of Surfactants, Engineering Books (1968), 183 pages

[0015] At least one surface layer of the polyolefin resin film of the present invention comprises 0.5 to 3% by weight of the surfactant (A) and 0.2 to 3% by weight of the surfactant (B). And the ratio [A] / [B] of the content [A] (% by weight) of the surfactant (A) to the content [B] (% by weight) of the surfactant (B) in the layer is The following expression (1) is satisfied. 1 ≦ [A] / [B] ≦ 5 (1) In the film of the present invention, the surface layer has a surfactant (A) of 1 to 2% by weight and a surfactant (B) of 0.5 to 2% by weight. ), And [A] / [B]
Is preferably 1.5 or more and 4 or less. When the amount of the surfactant (A) is 0.5% by weight or less, the antifogging property is not improved, and when the amount is 3% by weight or more, poor processability due to poor dispersion in a resin and the desired antifogging property are exhibited. Hard to do. When the amount of the surfactant (B) is 0.2% by weight or less, the antifogging property is not improved, and when the amount is 3% by weight or more, the appearance is deteriorated due to whitening. When [A] / [B] is 1.5 or less,
The appearance deteriorates due to bleeding of the surfactant (B),
If it is 4 or more, poor dispersibility in the resin results in poor processability, and the desired anti-fogging property is hardly exhibited.

Further, the film of the present invention comprises, as the surfactant (B), the surfactant (C) having an HLB of 6 or more and less than 12 and the surfactant (D) having an HLB of 2 or more and less than 6 When contained, the content of surfactant (A), surfactant (C) and surfactant (D),
[A] (% by weight), [C] (% by weight) and [D] (% by weight) preferably satisfy the following formulas (2) to (4). 2 <[A] / [C] <4 (2) 2 <[A] / [D] <4 (3) 1.5 <[A] + [C] + [D] <3 (4) The above condition Surfactants (A), (C),
When (D) is blended, extremely good anti-fogging property is achieved without causing deterioration in processability and anti-fogging property due to poor dispersion of the surfactant and poor appearance due to bleed whitening.

In the polyolefin resin film of the present invention, at least one surface layer has a content of 0.5 to 3% by weight.
Contains a surfactant (A) having an HLB of 12 or more and a surfactant (B) having an HLB of less than 12 at 0.2 to 3% by weight, and the content of the surfactant (B) [B] ( As long as the ratio [A] / [B] of the surfactant [A] (% by weight) to the surfactant [A] (% by weight) satisfies 1 ≦ [A] / [B] ≦ 5. Although a configuration may be adopted, a multilayer configuration including three to five layers is preferably employed. In the case of a multilayer film, the composition of each layer may be the same or different. Also, not all layers need to satisfy the above conditions, and at least one surface layer only needs to satisfy the above conditions. The film of the present invention exhibits excellent initial antifogging property and excellent low-temperature antifogging property on a surface satisfying the above conditions.

The thickness of the film of the present invention is determined in consideration of the film strength, the splicing workability of the film, and the coating workability.
Usually about 0.02-0.3 mm, preferably 0.03-
It is about 0.2 mm.

The film of the present invention can contain a light stabilizer in order to exhibit excellent weather resistance. As the light stabilizer, an inorganic light stabilizer such as a nickel compound can be used, but a hindered amine compound which is an organic light stabilizer is preferable. Examples of the hindered amine compound include those having a structural formula described in JP-A-10-52895. The light stabilizers may be used alone or in combination of two or more.

When a hindered amine compound is incorporated into the film of the present invention, the amount of the hindered amine compound is usually 0.02 to 5% by weight, preferably 0.1% by weight, based on the whole film, from the viewpoint of improving the weather resistance and suppressing blooming. 1-2% by weight,
More preferably, it is in the range of 0.5 to 2% by weight. Also,
In order to achieve a better effect of improving weather resistance, it is preferable to use the following ultraviolet absorber together with a light stabilizer.

The film of the present invention can contain an ultraviolet absorber. Ultraviolet absorbers that can be used in the present invention can be broadly classified into organic ultraviolet absorbers and inorganic ultraviolet absorbers. Main organic UV absorbers include benzophenone UV absorbers, benzotriazole UV absorbers, benzoate UV absorbers, cyanoacrylate UV absorbers, and the like.
Japanese Patent Application Laid-Open No. 0-52895 describes a structural formula. Examples of the inorganic ultraviolet absorber include metal oxides such as cerium oxide, titanium oxide, and zinc oxide. The ultraviolet absorbers may be used alone or in combination of two or more. When blending an ultraviolet absorber, the blending amount is, from the viewpoint of weather resistance improvement effect and blooming suppression,
It is usually in the range of 0.01 to 3% by weight, preferably 0.05 to 1% by weight, based on the whole film.

The film of the present invention can contain an anti-fog agent to exhibit anti-fog properties. Examples of the antifog agent include a fluorine compound having a perfluoroalkyl group or an ω-hydrofluoroalkyl group (especially a fluorine-based surfactant), and a silicon compound having an alkylsiloxane group (especially a silicon-based surfactant). be able to. When compounding an antifog, the compounding amount is usually 0.01 to 3% by weight, preferably 0.1% by weight based on the whole film.
The range is from 02 to 1% by weight.

The film of the present invention can contain a radiation blocking agent to exhibit excellent heat retention. Here, the radiation is an infrared ray radiated from an object in a wavelength range of 2 to 25 μm, and the radiation blocking agent is a substance having a property of absorbing or reflecting the radiation. Therefore,
As the radiation blocking agent, a substance usually used as an infrared absorbing agent or an infrared reflecting agent can be used.

As the infrared reflecting agent, a substance which reflects infrared light of at least one of the wavelengths in the above-mentioned wavelength region is selected, and examples thereof include inorganic infrared reflecting agents such as zinc oxide. The infrared absorbing agent is selected from a substance exhibiting an absorption peak at at least one of the wavelengths in the above wavelength range. Examples of the inorganic infrared absorbing agent include lithium aluminum composite hydroxide, hydrotalcite compounds, composite hydroxides such as calcium aluminum composite hydroxide, magnesium oxide, calcium oxide, aluminum oxide, silicon oxide, titanium oxide and the like. Metal oxides, metal hydroxides such as lithium hydroxide, magnesium hydroxide, calcium hydroxide, and aluminum hydroxide, magnesium carbonate, calcium carbonate, and basic aluminum carbonate (for example, a base described in JP-A-9-279131) Carbonates such as double aluminum carbonate), sulfates such as potassium sulfate, magnesium sulfate, calcium sulfate, zinc sulfate and aluminum sulfate, lithium phosphate,
Phosphates such as sodium phosphate, potassium phosphate, calcium phosphate, and zirconium phosphate (for example, H-type zirconium phosphate described in JP-A-8-67774); silicates such as magnesium silicate, calcium silicate, aluminum silicate, and titanium silicate; Aluminates such as sodium aluminate, potassium aluminate and calcium aluminate; aluminosilicates such as sodium aluminosilicate, potassium aluminosilicate and calcium aluminosilicate;
Examples include clay minerals such as kaolin, clay, and talc, and composite oxides. As the organic infrared absorber, polyacetal, polyvinyl alcohol and its derivatives,
Examples include an ethylene / vinyl alcohol copolymer. Among these radiation blocking agents, the density is 3 g / cm ³ or less, particularly 2.
It is preferably 4 g / cm ³ or less.

When the radiation blocking agent is an inorganic infrared absorbing agent, the refractive index thereof is closer to the refractive index of the resin material used from the viewpoint of light transmittance, and is broader from the viewpoint of heat insulation. It is preferable that infrared rays can be absorbed in the wavelength region. Preferred inorganic infrared absorbers include
Examples thereof include lithium aluminum composite hydroxide, hydrotalcite compounds, aluminosilicates, and basic aluminum carbonate double salts.

[0026] The A hydrotalcite compound represented by the following formula _{^{(I): M 2+ 1-}} x Al 3+ x (OH -) 2 (A 1 n-) x / n · mH 2 O (I) ( ^Wherein M ²⁺ is a divalent metal ion, A ₁ ⁿ⁻ is an n-valent anion, and x, m and n are 0 <x <0.5,
It is a number that satisfies the condition 0 ≦ m ≦ 2, 1 ≦ n. ) Is a composite hydroxide. As M ²⁺ , Mg ²⁺ ,
Ca ²⁺ and Zn ²⁺ are exemplified. As A ₁ ^n- , C
^{l -, Br -, I -} , NO 3 -, ClO 4 -, SO 4 2-, CO 3
^{_{2-, SiO 3 2-, HPO 4}} 3-, HBO 4 3-, PO 4 3-, Fe
^{_{(CN) 6 3 -, Fe}} (CN) 6 4-, CH 3 COO -, C 6 H
₄ (OH) COO ⁻ , (COO) ₂ ²⁻ , anions such as terephthalate ion and naphthalene sulfonate ion, and polysilicate ion and polyphosphate ion described in JP-A-8-217912. Specific examples include natural hydrotalcite and synthetic hydrotalcite such as DHT-4A (trade name, manufactured by Kyowa Chemical Industry Co., Ltd.). Calcium hydroxide or calcium aluminum complex hydroxide: CaAl _x
It is effective to use in combination with (OH) _{2 + 3x} .

[0027] The lithium as the aluminum complex hydroxide, for example, Japanese Unexamined following formulas described in 5-179052 JP ^{(II): Li + (Al} 3+) 2 (OH -) 6 · (A 2 n- _{1 / n} · mH ₂ O (II) (wherein A ₂ ⁿ⁻ is an n-valent anion, m and n
Is a number satisfying the condition 0 ≦ m ≦ 3, 1 ≦ n. )). A ₂ ^n- includes the same anions as A ₁ ^n- in the compound of the formula (I).

Examples of composite hydroxides other than the above two types of composite hydroxides include, for example, alkaline earth metals, transition metals, Z
A composite hydroxide containing at least one element selected from the group consisting of n and Si, Li and Al, and having a hydroxyl group is exemplified. Among the alkaline earth metals,
Magnesium and calcium are preferred. Further, among the transition metals, divalent or trivalent iron, cobalt, nickel and manganese are preferred, and iron is particularly preferred. The molar ratio of Al and Li (Al / Li) is usually 1.5
/ 1 to 2.5 / 1, preferably 1.8 / 1 to 2./1.
5/1. Alkaline earth metals, transition metals, Z
The molar ratio (a) of each element selected from the group consisting of n and Si is generally 0 <a <1.5, preferably 0.1 ≦ a ≦ 1.4, more preferably 0.1 mol, based on 1 mol of Li. Is 0.2 ≦ a ≦ 1.2. The anion portion other than the hydroxyl group of such a composite hydroxide includes, for example, pyrosilicate ion, cyclosilicate ion, isosilicate ion, phyllosilicate ion, perisilicate ion such as tectosilicate ion, carbonate ion, halide ion, sulfate ion, Inorganic acid ions such as sulfite ion, nitrate ion, nitrite ion, phosphate ion, phosphite ion, hypophosphite ion, aluminate ion, silicate ion, perchlorate ion, borate ion, Fe (C
^{_{N) 6 3-, Fe (CN}} ) 6 4 anionic transition metal complexes such as ^{chromatography,} acetate ion, benzoate ion, formic acid ion, terephthalate ion and organic acid ions such as an alkyl sulfonate ion. Among these, carbonate ions, halide ions, sulfate ions, phosphate ions, polyphosphate ions, silicate ions, polysilicate ions, and perchlorate ions are preferred, and carbonate ions, polyphosphate ions, silicate ions, and polysilicate ions are particularly preferred. preferable.

Specific examples of such a composite hydroxide include Al, Li and Mg, and include Al / Li / Mg.
= About 2.3 / 1 / 0.28 (molar ratio), a composite hydroxide (trade name: LMA, manufactured by Fuji Chemical Industry), Al, L
i / Si, Al / Li / Si = about 2/1 /
1.2 (molar ratio) composite hydroxide (trade name: Fujilein LS, manufactured by Fuji Chemical Industry).

[0030] WO97 / 00828 disclosed the following formula ^{(III): [(Li +} (1-x) M 2+ x) (Al 3+) 2 (OH -) 6] 2 (S
i _y 0 _{(2y + 1)} ²⁻ ) _{(1 + x)} · mH ₂ O (III) (where M ²⁺ is a divalent metal ion, m, x
And y are numbers satisfying the conditions of 0 ≦ m <5, 0 ≦ x <1, and 2 ≦ y ≦ 4. ) And the following formula (IV) disclosed in JP-A-8-217912: [(Li ⁺ _(1-x) M ²⁺ _x ) (Al ³⁺ ) ₂ (O
H ⁻ ) ₆ ] ₂ (A ⁿ⁻ ) _{2 (1 + x) / n} · mH ₂ O (IV) (where M ²⁺ is a divalent metal ion and A ⁿ⁻ is n
M, x and n are 0 ≦ m <5,
It is a number that satisfies the condition of 0.01 ≦ x <1, 1 ≦ n. The compound represented by ()) is a preferable example of the composite hydroxide. Examples of M ²⁺ in formulas (III) and (IV) include Mg ²⁺ , Ca ²⁺ , and Zn ²⁺ . Further, a basic aluminum carbonate double salt disclosed in JP-A-9-279131 is also one of the preferred infrared absorbers.

When the above-mentioned complex hydroxide or basic aluminum carbonate double salt is used as a radiation blocking agent, its average particle size is usually 5 μm or less, preferably 0.05 to 3 μm.
μm, and more preferably 0.1 to 1 μm. Also, B
The specific surface area measured by the ET method is 1 to 30 m ² / g,
Preferably it is ^{2 to 20} m ² / g.

In an antifogging film used for applications requiring a high degree of transparency, the refractive index of the radiation blocking agent is preferably close to the refractive index of the polyolefin resin used, and is described in JIS K0062. Is preferably from 1.47 to 1.55, more preferably from 1.48 to 1.54, and more preferably from 1.49 to 1.54.
1.53 is particularly preferred. In order to improve the dispersibility of the radiation blocking agent in the film, the radiation blocking agent may be subjected to a surface treatment with a higher fatty acid or an alkali metal salt of a higher fatty acid.

In the film of the present invention, the radiation blocking agent may be used alone or in combination of two or more. The content of the radiation blocking agent in the film of the present invention is appropriately set depending on the type of the radiation blocking agent and the resin to be used, as long as the transparency and mechanical strength of the film are not significantly impaired. For example, when using the above composite hydroxide as a radiation blocking agent, the compounding amount is, based on the entire film,
Usually 0.03 to 25% by weight, preferably 3 to 13% by weight
It is about.

The film of the present invention can contain a near infrared ray blocking agent. The near-infrared blocking agent may be used alone or in combination of two or more. The inside of the house covered with the anti-fogging film containing the near-infrared ray blocking agent is suppressed from increasing in temperature due to sunlight. As the near-infrared ray blocking agent, organic compounds disclosed in JP-A-10-193522 (for example, nitroso compounds and metal complex salts thereof, cyanine compounds, squarylium compounds, thiol nickel complex salt compounds, phthalocyanine compounds,
Triallylmethane compounds, immonium compounds, diimonium compounds, naphthoquinone compounds, anthraquinone compounds, amino compounds, aminium salt compounds)
And inorganic compounds (eg, carbon black, antimony oxide, tin oxide doped with indium oxide, oxides of metals belonging to Groups 4A, 5A and 6A of the periodic table, or carbides or boron compounds).

A film containing a near-infrared ray blocking agent may be formed on the surface of the film of the present invention. The coating can be formed, for example, by applying a liquid containing a near-infrared ray blocking agent and a water-soluble resin binder to the anti-fogging film and drying. Also in this case, the near-infrared blocking agent is
They may be used alone or in combination of two or more. Further, an antifogging film may be formed on the surface of the film of the present invention. By providing this, antifogging property is exhibited for a long period of time.

The film of the present invention may contain, if necessary, various antioxidants, heat stabilizers, antiblocking agents, lubricants, antistatic agents, pigments and the like generally used in the field of agricultural films. Additives can be included. Such additives are described in the literature "Separation and analysis technology of polymer additives, Tanaka et al., 1987, Japan Science Information Co., Ltd." and "Handbook of Additives for Plastics and Rubber, Goto et al., 1970, ( Co., Ltd.).

The film of the present invention may be subjected to a corona treatment on its surface. Since the surface is corona-treated, bleeding of the surfactant is suppressed, and the antifogging property can be maintained for a long time. The strength of the corona treatment is set within a range where the mechanical strength of the film is not impaired and blocking does not occur, and is preferably about ^{20 to} 60 W · min / m ² .

The film of the present invention can be produced, for example, by preparing a resin composition for each layer and molding them by a co-extrusion method such as a T-die film forming method or an inflation film forming method. The resin composition for each layer is prepared by adding a predetermined amount of a surfactant (anti-fogging agent) to a polyolefin resin and, if necessary, a light stabilizer, an ultraviolet absorber, an anti-mist agent, a radiation blocking agent, and a near infrared blocking agent. Add various additives such as anti-fogging agents other than the above surfactants, antioxidants, heat stabilizers, lubricants, anti-blocking agents, pigments, etc.
It can be prepared by mixing and kneading using a kneader. Ribbon blender,
Super mixer, Banbury mixer, single screw extruder,
An ordinary device such as a twin screw extruder can be used.

The film of the present invention has an excellent antifogging property, especially an initial antifogging property and a low-temperature antifogging property, since the whitening of the film due to a sudden bleeding of a surfactant (antifogging agent) on the surface thereof is suppressed. It is suitably used as a covering film for greenhouses and tunnels. It is also preferably used as a lining curtain provided in the agricultural facility.

[0040]

EXAMPLES The present invention will be described below in detail with reference to examples, but the present invention is not limited to these examples. The test methods in the following Examples and Comparative Examples are as follows.

(Bleaching) HAZ of a sample film immediately after production and after aging using a haze meter HGM-2DP (manufactured by Suga Test Instruments) in accordance with JIS K7105.
E was measured and the difference (ΔHaze) between the two was determined. ΔHA
The smaller the value of ZE, the less whitening.

(Anti-fogging property) A sample film attached to an acrylic frame having a length of 34 cm and a width of 5 cm with a double-sided tape was tested at 30 ° C. and 80% RH with its test surface facing down.
After storing for 4 hours, put it on the water bath in the environmental test room.
An antifogging test was performed by setting the test surface and the horizontal surface so as to form a 15 ° angle. Test temperature (room temperature of environmental test room
The water temperature of the constant temperature water tank is 3 ° C./20 in the low temperature test.
C., 20 ° C./40° C. in the high temperature test. The state of water droplets on the test surface of the sample film was observed over time, and the antifogging property at each observation point was determined according to the following criteria. ◎: No trace of flow was observed, and the test surface was uniformly wet. ：: There is no water droplet, but a trace of flow is observed. Δ: Water droplets are partially adhered. ×: Water droplets adhered, and the film was white and cloudy.

(Examples 1 to 7) 0.6% by weight of ethylene / vinyl acetate copolymer (trade name: Evatate D2011; vinyl acetate unit content = 5% by weight; manufactured by Sumitomo Chemical Co., Ltd.)
Hindered amine compound (trade name: Tinuvin 622)
-LD; manufactured by Ciba Specialty Chemicals), 0.1% by weight of an antioxidant (trade name: Irganox 1010; manufactured by Ciba Specialty Chemicals), and surfactants (A) and (B) of the type and amount described in Table 1 ) Was blended and kneaded at 130 ° C for 5 minutes using a Banbury mixer, and then granulated by a granulator to obtain pellets of the resin composition. The amount of each component described above and in Table 1 is a value based on the total weight of the obtained resin composition. Using the pellets, a film having a thickness of 0.1 mm was produced by an inflation molding machine. 30 ° C, 80
After aging for 12 hours under% RH conditions, the whitening and anti-fog properties were tested. The results were all good as shown in Table 1.

Comparative Examples 1 to 5 Films were prepared in the same manner as in Example 1 except that the surfactants (A) and (B) of the types and amounts shown in Table 2 were used, and whitening and prevention were carried out. Haze was tested. The results were all inferior as shown in Table 2.

(Examples 8 and 10) 0.1% of an ethylene / vinyl acetate copolymer (trade name: Evatate H2031, vinyl acetate unit content = 19% by weight; manufactured by Sumitomo Chemical Co., Ltd.)
6% by weight of a hindered amine compound (trade name: Tinuvin 622-LD; manufactured by Ciba Specialty Chemicals),
10% by weight of lithium-aluminum composite hydroxide (infrared absorbing agent) (trade name: Mizukarac; manufactured by Mizusawa Chemical Industries), 0.1% by weight of ultraviolet absorbing agent (trade name: Sumisorb 130; manufactured by Sumitomo Chemical Co., Ltd.) 0.1% by weight of antioxidant (trade name: Irganox 1010; manufactured by Ciba Specialty Chemicals), 0.1% by weight of fluorine compound (antifog) (trade name: DS-403; manufactured by Daikin Industries) and Table 3 Of surfactants (A) and (B) of the type and amount described in 1 above, and using a Banbury mixer to add
After kneading at 5 ° C. for 5 minutes, the mixture was granulated by a granulator to obtain pellets of the resin composition. Hereinafter, this resin composition is referred to as a resin composition (1). The amounts of each component described above and in Table 2 are values based on the total weight of the obtained resin composition (1). On the other hand, an ethylene / vinyl acetate copolymer (trade name: Evatate D2011; vinyl acetate unit content = 5)
Weight%; manufactured by Sumitomo Chemical Co., Ltd.), 0.6 weight% of a hindered amine compound (trade name: Tinuvin 622-LD; manufactured by Ciba Specialty Chemicals), 0.1 weight of an antioxidant (trade name: Irganox 1010; Ciba Specialty Chemicals), 0.1% by weight of a fluorine compound (antifog agent) (trade name: DS-403; manufactured by Daikin Industries, Ltd.), 0.2% by weight of ethylenebisstearic amide (lubricant), and Table 3 After adding the surfactants (A) and (B) of the type and amount described in (1) and kneading the mixture at 130 ° C. for 5 minutes using a Banbury mixer, the mixture was granulated with a granulator to obtain resin composition pellets. . Hereinafter, this resin composition is referred to as a resin composition (2). The amount of each component described above and in Table 2 is a value based on the total weight of the obtained resin composition (2). Furthermore, low-density polyethylene (trade name: Sumikasen F208-0; manufactured by Sumitomo Chemical Co., Ltd.)
0.6% by weight of a hindered amine compound (trade name: Tinuvin 622-LD; manufactured by Ciba Specialty Chemicals), 0.1% by weight of an ultraviolet absorber (trade name: Sumisorb 130; manufactured by Sumitomo Chemical Co., Ltd.), 0.1% by weight Antioxidant (trade name: Irganox 1010; manufactured by Ciba Specialty Chemicals), 0.1% by weight of a fluorine compound (antifog agent) (trade name: DS-403; manufactured by Daikin Industries, Ltd.)
2% by weight ethylene bisstearic acid amide (lubricant),
And the surfactants (A) and (B) of the type and amount described in Table 3 as antifogging agents, kneaded at 130 ° C. for 5 minutes using a Banbury mixer, and then granulated with a granulator to obtain a resin. A pellet of the composition was obtained. Hereinafter, this resin composition is referred to as a resin composition (3). The amount of each component described above and in Table 2 is a value based on the total weight of the obtained resin composition (3). Using the above three types of resin compositions, a film having a thickness of 0.1 mm including an inner layer, an intermediate layer, and an outer layer was produced by an inflation film molding machine. Here, the intermediate layer, the inner layer and the outer layer are respectively a resin composition (1), a resin composition (2) and a resin composition.
It consisted of (3). The thickness of the intermediate layer is 0.06 mm,
The thickness of both the inner and outer layers was 0.02 mm. The film was aged under a condition of 23 ° C. and 50% RH for 4 days, and then tested for whitening and anti-fogging property. Table 3 shows the results
As shown in Table 2, all were good.

(Comparative Examples 6 to 8) Films were prepared in the same manner as in Example 9 except that the surfactants (A) and (B) of the types and amounts shown in Table 3 were used, and whitening and prevention were performed. Haze was tested. The results were all inferior as shown in Table 3.

Example 9 A film was prepared in the same manner as in Example 9 except that the types and amounts of the surfactants (A) and (B) shown in Table 3 were used. After subjecting the surface to a corona treatment (strength: 43 W · min / m ² ), whitening and anti-fogging properties were tested. The results were good as shown in Table 3.

[0048]

[Table 1] The unit of the numerical value in parentheses in the table is% by weight. A-1: Polyoxyethylene (20) monostearate (HLB = 15.4) C-1: Polyoxyethylene (2) stearylamine (HLB = 6.1) C-2: Polyoxyethylene (5) polyserine monostearate (HLB = 16.1) (HLB = 10.2) C-3: Polyoxyethylene (3) polyserine sesquistearate (HLB = 8.1) C-4: Tetraglycerine monostearate (HLB = 10.2) D-1: Polyserine monostearate (HLB = 4.1) D-2: Polyoxyethylene (2) monostearylamine monostearate (HLB = 2.9) D-3: Polyoxyethylene (4) monostearylamine monostearate (HLB = 4.3)

[0049]

[Table 2] The unit of the numerical value in parentheses in the table is% by weight. A-1: Polyoxyethylene (20) monostearate (HLB = 15.4) C-1: Polyoxyethylene (2) stearylamine (HLB = 6.1) C-2: Polyoxyethylene (5) polyserine monostearate (HLB = 16.1) (HLB = 10.2) C-3: Polyoxyethylene (3) polyserine sesquistearate (HLB = 8.1) C-4: Tetraglycerine monostearate (HLB = 10.2) D-1: Polyserine monostearate (HLB = 4.1) D-2: Polyoxyethylene (2) monostearylamine monostearate (HLB = 2.9) D-3: Polyoxyethylene (4) monostearylamine monostearate (HLB = 4.3)

[0050]

[Table 3] The unit of the numerical value in parentheses in the table is% by weight. A-1: Polyoxyethylene (20) monostearate (HLB = 15.4) C-1: Polyoxyethylene (2) stearylamine (HLB = 6.1) D-1: Polyserine monostearate (HLB = 4.1) D- 2: Polyoxyethylene (2) monostearylamine monostearate (HLB = 2.9)

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4F071 AA15 AA15X AA20 AA20X AA21 AA21X AA28 AA28X AA32 AA32X AA33 AA33X AA51 AA78 AC10 AE10 AF04Y AF56 BA01 BB09 BC01 4J002 BB031 BB06 BB051BB06 BB05 BB05

Claims (5)

[Claims] 1. A film comprising a polyolefin resin, wherein at least one surface layer of the film has a thickness of 0.5
Content of surfactant (B) containing ３3% by weight of HLB having a surfactant of 12 or more (A) and 0.2-3% by weight of HLB having a surfactant of less than 12 (B) [B]
(A) Content of surfactant (A) based on (% by weight)
A polyolefin-based resin film, wherein the ratio (A) / [B] of (% by weight) satisfies the following formula (1). 1 ≦ [A] / [B] ≦ 5 (1) 2. The surfactant (B) having an HLB of 6
2. The polyolefin resin film according to claim 1, comprising a surfactant (C) having at least 12 but less than 12 and a surfactant (D) having an HLB of at least 2 and less than 6. 3. 3. The surfactant (A) is selected from the group consisting of polyoxyethylene sorbitan fatty acid ester, polyoxyethylene glycerin fatty acid ester, polyoxyethylene alkylamine, polyoxyethylene alkylamine fatty acid ester and polyglycerin fatty acid ester. The polyolefin resin film according to claim 1, wherein the polyolefin resin film is at least one selected surfactant. 4. The surfactant (A) having a polyoxyethylene sorbitan fatty acid ester, a polyoxyethylene glycerin fatty acid ester, a polyoxyethylene alkylamine, or a polyoxyethylene alkylamine fatty acid ester, wherein the number of ethylene oxide groups per molecule is as follows. 10-2
The polyolefin resin film according to claim 3, wherein the number is five. 5. The content of the surfactants (A), (C) and (D) [A] (% by weight), [C] (% by weight) and [D] (% by weight) is represented by the following formula: The polyolefin-based resin film according to claim 2, wherein (2) to (4) are satisfied. 2 <[A] / [C] <4 (2) 2 <[A] / [D] <4 (3) 1.5 <[A] + [C] + [D] <3 (4)