JPH08132563A - Laminated film for agriculture - Google Patents

Abstract

PURPOSE: To provide a laminated film for agriculture, being excellent in resistance to scuffing and in toughness irrespective of excellent flexibility and having excellent workability without having any adhesion trouble. CONSTITUTION: A resin layer B comprising an olefin-based polymer composition containing 5 to 40wt.% of a hydrogenated diene copolymer is laminated on at least one face of a resin layer A. The resin layer A is a layer mainly composed of an olefin-based polymer while the resin layer B is a layer which is composed of a polypropylene polymer composition containing 0.5 to 20wt.% of an inorganic filler and which comprises two or more kinds and two or more layers. The inorganic filler is mainly composed of either one of hydrotalcite or an composite aluminum lithium hydroxide.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to agricultural laminated films. More specifically, the present invention relates to a laminated film for agriculture which is excellent in flexibility, scratch resistance and toughness, and has excellent workability without adhesion trouble.

[0002]

2. Description of the Related Art A large amount of plastic films are used as facility horticultural materials, and typical ones are polyvinyl chloride film (hereinafter referred to as agricultural plastic), polyethylene film (hereinafter referred to as agricultural poly), and ethylene vinyl acetate. Polymer films (hereinafter referred to as agricultural vinegar) are listed. Among them, agricultural vine is excellent in heat retention, transparency, toughness, antifogging property, house adhesion and economical efficiency, and is the most common. in use. However, farm work is inferior in workability and dust resistance due to stickiness, and recently, various problems such as generation of harmful gas at the time of incineration and disposal are occurring, and a substitute thereof is desired. On the other hand, although agricultural poly and agricultural vinegar have advantages over agricultural vinyl in terms of workability, dust resistance, and disposal, they are inferior in toughness, scratch resistance, house adhesion, etc. It was used only in the field.

Polypropylene resin is superior in strength and scratch resistance as compared with polyethylene resin and ethylene-vinyl acetate copolymer, but it is inferior in flexibility and cannot be practically used as an agricultural film. It was

In order to fundamentally solve the conventional problems in the laminated film for agriculture as described above, and further to improve the flexibility of the polypropylene resin, the present inventors have conducted diligent studies, and as a result, have found that the olefin resin is used. By laminating a resin layer B made of a propylene-based polymer containing a hydrogenated diene-based copolymer on at least one surface of the resin layer A as a main component,
It has become possible to provide a laminated film for agriculture which has flexibility, excellent toughness, scratch resistance and transparency, and has excellent workability without adhesion trouble.

[0005]

The present invention has the following constitution. (1) A laminated film for agriculture in which a resin layer B made of an olefin polymer composition containing 5 to 40% by weight of a hydrogenated diene copolymer is laminated on at least one surface of the resin layer A. (2) The resin layer A is a layer whose main component is an olefin polymer, and the resin layer B is 0.5 to 20% by weight of an inorganic filler.
A laminated film for agriculture, which is a polypropylene polymer composition containing two or more layers and two or more layers. (3) The agricultural filler as described above, wherein the inorganic filler is a hydrotalcite represented by the following general formula (1) or an aluminum-lithium composite hydroxide salt represented by the general formula (2) as a main component. Laminated film. General formula (1) M ²⁺ _1-X Al _X (OH) ₂ (A ⁿ⁻ ) _{X / n} · mH ₂ O (wherein M ²⁺ is 2 selected from the group consisting of magnesium, calcium and zinc) Represents a valent metal ion, A ^n- represents an n-valent anion, _X and m are as follows, 0 < _X <
0.5, 0 ≦ m ≦ 2 is satisfied. ) General formula (2) [Al ₂ Li (OH) ₆ ] _n X · mH ₂ 0 (wherein, X is an inorganic or organic anion,
n is the valence of the anion X, and m is 3 or less. )

Hereinafter, the present invention will be described in detail. The resin layer A used in the present invention is specified as a thermoplastic resin, and is preferably an olefin polymer, and may be a single layer or a multilayer of two or more layers. In the case of two or more layers, for example, lamination of an antifogging layer and a heat retaining layer, lamination of an antifogging layer, a film strength improving layer and a heat retaining layer, lamination of a different polymer layer and an adhesive layer, lamination of a heat retaining layer and a dustproof reinforcement layer. Etc.

The olefin polymer used in the present invention is preferably a homopolymer or copolymer of at least one α-olefin selected from ethylene, propylene, 1-butene, 1-pentene, 1-hexene and the like. To be More preferably, a propylene olefin polymer,
Examples include propylene homopolymers, propylene random copolymers with one or more α-olefins selected from ethylene, 1-butene, 1-pentene, 1-hexene, ethylene-propylene block copolymers, etc., but transparency ,
A random copolymer with an α-olefin is particularly preferably used from the viewpoint of flexibility and heat sealability.

The hydrogenated diene-based copolymer is disclosed in
-72512, it comprises a vinyl aromatic compound polymer block (A) and a conjugated diene polymer, or a random copolymer block (B) of a vinyl aromatic compound and a conjugated diene (A)- (B) Block copolymer, or (A)-(B)-(C) block comprising a vinyl aromatic compound and a taper block (C) in which the vinyl aromatic compound of the conjugated diene is gradually increased if necessary. Copolymer or (A)-(B)-(A) block copolymer consisting of vinyl aromatic polymer block (A), where the ratio of vinyl aromatic compound / conjugated diene in all monomers is by weight The ratio is 5 to 60/95 to 40, and the bonding content of the binding compound of the vinyl aromatic compound in the component (A) and the component (C) that is optionally constituted is 3 to 5 of all the monomers. Bond content in weight%, and (A) a vinyl aromatic compound in the component is at least 3% by weight,
The vinyl bond content of the conjugated diene part in the component (B) is 60.
Hydrogenated (hydrogenated) block copolymers exceeding 100% are preferably used. At least 80% of the double bonds in the conjugated diene moiety after hydrogenation are saturated, and those having a number average molecular weight of 50,000 to 600,000 are preferably used.

The blending amount of the hydrogenated diene-based copolymer used in the resin layer B of the present invention is such that
5-40% by weight. When the blending amount is less than 5% by weight,
The flexibility, transparency, elastic recovery, anti-fogging sustainability, etc. of the obtained film are not remarkably observed, and when it exceeds 40% by weight, the strength of the obtained film is decreased, Poor workability due to close contact occurs.

The olefin resin used in the resin layer A is a homopolymer of α-olefin or a copolymer of α-olefin with a different monomer, such as propylene homopolymer or Ethylene, a propylene-based polymer that is a copolymer with ethylene-butene, an ethylene homopolymer, 1-butene, 1-pentene, 1-hexene,
4-methyl-1-pentene, 1-octene, ethylene-based polymers which are copolymers with vinyl acetate can be mentioned.
Ethylene polymers are preferably used for improving flexibility, weather resistance and transparency, and also from the viewpoint of cost. These resins may be used alone or in combination of two or more kinds. May be.

Of these, an ethylene polymer having a density of 0.88 to 0.935 g / cm ³ is preferably used because it has appropriate flexibility and transparency, but has a melt index of 0.1 g.
/ 10 minutes or less has a problem of workability, and 5g / 10 minutes or more has a decrease in strength, so the melt index is 0.1g / 10 minutes or more and 5g / 10 minutes or less. The thing of is desirable.

Further, an elastic copolymer can be added to medium / high density polyethylene and low density polyethylene. Thereby, it was possible to impart flexibility and improve the durability of the antifogging agent. As the elastic copolymer, known elastic copolymers such as ethylene-propylene rubber which is an ethylene-propylene elastic copolymer, polybutadiene rubber, styrene-butadiene rubber, acrylonitrile butadiene rubber, polyisoprene rubber, and styrene-isoprene rubber are used. When the main component of the resin layer A is an ethylene-based polymer, it is preferable to use an ethylene-propylene elastic copolymer in order to maintain transparency, and the Mooney viscosity is 20 to 70 ML _{1 + 4.} It is about (100 ° C.) and the propylene unit content is preferably about 20 to 50% by weight. Mooney viscosity of 20ML _{1 + 4} (10
If the temperature is less than 0 ° C), the film strength will decrease, and 70ML _{1 + 4} (10
If the temperature exceeds 0 ° C., the film forming processability tends to be poor and the internal haze value tends to decrease. It should be noted that these elastic copolymers may be added in combination with the hydrogenated diene-based copolymer of the resin layer B.

Further, the ethylene-vinyl acetate copolymer is used for the purpose of improving flexibility and has a vinyl acetate content of
It is preferably 30% by weight or less and 5% by weight or more, and the melt index is 0.1 g / 10 minutes or more and 5 g / 10 minutes or less. If the vinyl acetate content is 30% by weight or more, the processability will decrease,
If it is less than 5% by weight, the same properties as those of other ethylene-based polymers can be obtained. Also, if the melt index is less than 0.1 g / 10 minutes, the processability will decrease, and
If it is more than a minute, the strength will decrease.

In the present invention, an inorganic filler can be added to the resin layer B, which can prevent the films from adhering to each other. The amount added is in the range of 0.5 to 20% by weight in the olefin polymer composition, if less than 0.5% by weight it is difficult to obtain the effect of preventing adhesion, and if it exceeds 20% by weight, the transparency of the film is poor, It is not preferable because the physical properties of the film are inferior. In addition to the purpose of the present invention, a wavelength of 10 μm is used for the purpose of improving the heat retaining property of the agricultural film.
An inorganic filler having infrared absorption in the vicinity may be added to the resin layer A.

Examples of the inorganic filler include silicon oxide, magnesium silicate, aluminum silicate, calcium silicate and other silicate compounds, calcium aluminosilicate, sodium aluminosilicate, aluminosilicate compounds such as potassium aluminosilicate, alumina, sodium aluminate and potassium aluminate. , One selected from the group consisting of aluminate compounds such as calcium aluminate, calcium carbonate, hydrotalcites represented by the general formula (1) and lithium-aluminum complex hydroxide salts represented by the general formula (2). The above-mentioned inorganic fillers can be mentioned. General formula (1) M ²⁺ _1-X Al _X (OH) ₂ (A ⁿ⁻ ) _{X / n} · mH ₂ O (wherein M ²⁺ is 2 selected from the group consisting of magnesium, calcium and zinc) Represents a valent metal ion, A ^n- represents an n-valent anion, _X and m are as follows, 0 < _X <
0.5, 0 ≦ m ≦ 2 is satisfied. ) General formula (2) [Al ₂ Li (OH) ₆ ] _n X · mH ₂ 0 (wherein, X is an inorganic or organic anion,
n is the valence of the anion X, and m is 3 or less. )

The transparency of the agricultural laminated film varies depending on the type of the inorganic filler, and it is preferable that the refractive index of the olefin polymer and the refractive index of the inorganic filler are close to each other, and the transparency can be improved by using the inorganic filler having a close refractive index. improves. The hydrotalcites represented by the above general formulas (1) and (2), lithium-aluminum complex hydroxide salts, and the like are preferably used.

In the production of the laminated film according to the present invention, various additives such as an antifogging agent, an antifog agent, a heat stabilizer, a weather resistance improver and a slip agent may be added according to a conventional method.

Examples of the antifogging agent include cationic surfactants, anionic surfactants, amphoteric surfactants and nonionic surfactants, and two or more kinds of antifogging agents are used for the purpose of improving antifogging sustainability. A clouding agent may be used in combination.

Examples of the anti-fog agent include anionic fluorosurfactants, cationic fluorosurfactants, amphoteric fluorosurfactants, nonionic fluorosurfactants, and other fluorosurfactants. These may be used alone or in combination of two or more.

As the heat stabilizer, a known phosphorus-based stabilizer,
Examples thereof include phenolic stabilizers and thiol stabilizers, which may be used alone or in combination.

Examples of the weather resistance improver include known benzotriazole compounds, benzophenone compounds, ultraviolet absorbers such as salicylic acid derivative compounds, and light stabilizers typified by hindered amine compounds. Among them, hindered amine compounds have been used for a long time as weather resistance improvers for polyolefin resins. Further, the ultraviolet absorber has been used for a long time in the field of agricultural films since it not only improves the weather resistance but also cuts ultraviolet rays having a specific wavelength, and these are used alone or in combination.

The agricultural laminated film of the present invention can be produced by known laminating techniques such as coextrusion molding by the inflation method or T-die method, wet lamination, dry lamination, hot melt lamination, extrusion coating lamination, etc. Co-extrusion molding by the inflation method or T-die method, which has excellent properties, is generally used.

Even if the resin layer B is laminated on one surface of the thermoplastic resin layer A, flexibility, toughness, scratch resistance, non-adhesion, transparency, etc. can be obtained and the object of the present invention can be achieved. When laminated on both sides of the resin layer A, each effect is further improved by a synergistic effect.

The thickness of the agricultural laminated film of the present invention varies depending on the place of use, service life, etc., but is generally 0.05 to 0.
Those having a size of about 20 mm are preferably used. The thickness of the resin layer B is not particularly limited and is determined by required flexibility, toughness, total thickness of the laminated film and the like.

[0025]

EXAMPLES The present invention will be specifically described below with reference to Examples and Comparative Examples, but the present invention is not limited thereto. The melt flow rate (MFR) shown in Examples and Comparative Examples is a value measured by the method specified in JIS-K-7210. The toughness of the film is ASTM-
The tensile strength was measured according to D-882 and used as an index of toughness. Regarding transparency, the haze value and total light transmittance of the film were measured using a haze meter in accordance with JIS-K-7105 and used as a measure of transparency. Flexibility is a property that improves workability when extended in a house or tunnel, and Young's modulus was measured according to ASTM-D-882 and used as an index of flexibility. The scratch resistance is a property of preventing damage from being caused by a band or sand and preventing deterioration of transparency, and was evaluated by measuring a haze value after the film surface was abraded 5000 times with a flannel cloth. Also, regarding the workability of spreading,
The problem of poor workability due to stickiness when spread in the house was evaluated by 3 ranks of A (excellent), B (some problems but can be actually used), and C (not actually usable). . Adhesion of the film to the frame is a necessary property to prevent the coating film from fluttering due to wind and rain.
The evaluation was made in three ranks of A (excellent), B (some problems but can be actually used), and C (not actually usable).

Examples 1 to 4 MFR (190) was used by using a three-layer T-die forming apparatus capable of forming a two-kind three-layer film having a 90φ extruder and a 50φ extruder.
℃, 2.16kgf, A) = 2.0g / 10 minutes, density ρ = 0.95g / cm ³ , vinyl acetate content = 15wt% ethylene-vinyl acetate copolymer as the main component, sorbitan monostearate 1.0 weight %, Polyglycerin monostearate 0.5% by weight, hydrotalcite compound (trade name; DHT-4A, manufactured by Kyowa Kagaku Co., Ltd.) 5% by weight, hindered amine weathering agent (trade name; manufactured by Sanol LS 770 Ciba Geiger Co., Ltd.) ) 0.2% by weight, phenolic stabilizer (trade name: Irganox 1010 manufactured by Ciba Geiger Ltd.) 0.1% by weight, phosphorus-based stabilizer (trade name: Irgafos 1)
68 A resin composition containing 0.1% by weight of Ciba Geiger Co., Ltd. was charged into a 90φ extruder to form a resin layer A, and MFR (230 ° C.,
2.16 kgf, A) = 6.0 g / 10 min, density ρ = 0.90 g / cm ³ Mainly composed of a polypropylene ternary random copolymer with ethylene and butene as a comonomer, and total bound styrene content = 10% by weight, MFR (230 ℃, 2.16kgf, A) = 3.5g / 10min, density ρ ＝
Hydrogenated styrene-butadiene copolymer (trade name: DYNARON 1320P, manufactured by Nippon Synthetic Rubber Co., Ltd.) of 0.89 g / cm ^{3 in the amount} of 5, 10, 20, 40% by weight, respectively, and hydrotalcite as an inorganic filler Compound (trade name; DHT-4A, Kyowa Chemical Co., Ltd.)
1.0% by weight, sorbitan monostearate 1.0% by weight, polyglycerin monostearate 0.5% by weight, hindered amine weathering agent (trade name; manufactured by Sanol LS 770 Cibagie Co., Ltd.) 0.2% by weight, phenolic stabilizer ( Product name; Ir
ganox 1010 0.1% by weight, Phosphorus stabilizer (trade name; Irgafos 168, manufactured by Ciba Geiger) 0.1% by weight
The resin composition containing B is charged into a 50φ extruder and resin layer B is added.
And the die temperature of 200 ° C and the extrusion rate of 100 kg / hr,
A 100-μm-thick three-layer laminated film having a structure in which the resin layer B (thickness 70 μm) and the resin layer B (thickness 15 μm) were laminated on both sides was obtained.

Examples 5 to 9 Hydrogenated styrene-butadiene copolymer (trade name: D
20% by weight of YNARON 1320P, manufactured by Japan Synthetic Rubber Co., Ltd., a hydrotalcite compound (trade name; D) as an inorganic filler.
HT-4A, Kyowa Chemical Co., Ltd.) 0, 0.5, 5.0, 10, 20 respectively
Example 1 was carried out in the same manner as in Example 1 except that the weight% was set.

Example 10 The procedure of Example 5 was repeated except that the content of the hydrotalcite compound (trade name: DHT-4A, manufactured by Kyowa Kagaku Co., Ltd.) as an inorganic filler was 30% by weight.

Example 11 Hydrogenated styrene-butadiene copolymer (trade name: D
20% by weight of YNARON 1320P, manufactured by Japan Synthetic Rubber Co., Ltd., a hydrotalcite compound (trade name; D) as an inorganic filler.
HT-4A, manufactured by Kyowa Chemical Co., Ltd., in the same manner as in Example 1 except that the lithium-aluminum composite hydroxide salt (trade name; Miscaraque, manufactured by Mizusawa Chemical Co., Ltd.) was 1.0% by weight. Carried out.

Comparative Examples 1-2 Hydrogenated styrene-butadiene copolymers (trade name: D
The same procedure as in Example 1 was carried out except that YNARON 1320P, manufactured by Japan Synthetic Rubber Co., Ltd.) was 0 and 50% by weight.

Comparative Example 3 Resin layer B contains MFR (190 ° C., 2.16 kgf, A) = 3.0 g / 10 minutes, density ρ = 0.95 g / cm ³ , vinyl acetate content = 5 wt% ethylene-vinyl acetate. 1.0% by weight of a hydrotalcite compound (trade name; DHT-4A, manufactured by Kyowa Chemical Industry Co., Ltd.) as an inorganic filler containing a copolymer as a main component, 1.0% by weight of sorbitan monostearate, 0.5% by weight of polyglycerin monostearate. %, Hindered amine weathering agent (trade name: Sanol LS 770
Ciba Geiger Co., Ltd.) 0.2% by weight, phenolic stabilizer (trade name; Irganox 1010 Chiva Geiger Co., Ltd.) 0.1 wt%, phosphorus stabilizer (trade name: Irgafos 168 Chibagy Co., Ltd.)
Example 1 was carried out in the same manner as in Example 1 except that the resin composition containing 0.1% by weight was used.

Comparative Example 4 The resin layer B was mainly composed of an ethylene-1-hexene copolymer having MFR (190 ° C., 2.16 kgf, A) = 2.5 g / 10 minutes and a density ρ = 0.92 g / cm ³ . Hydrotalcite compound (trade name; DHT-4A, Kyowa Chemical Co., Ltd.) 1.0% by weight, sorbitan monostearate 1.0% by weight, polyglycerin monostearate 0.5% by weight, hindered amine-based weathering agent (product) Name: Sanol LS 770 manufactured by Ciba Geigy Ltd.)
2% by weight, phenolic stabilizer (trade name; manufactured by Irganox 1010 manufactured by Ciba Geigy Ltd.) 0.1% by weight, phosphorus stabilizer (trade name; I)
Example 1 was repeated, except that a resin composition containing 0.1% by weight of rgafos 168 manufactured by Ciba Geiger Co., Ltd. was used.

[0033]

The agricultural laminated film of the present invention has a resin layer B composed of a propylene-based polymer containing a hydrogenated diene copolymer, which is laminated on at least one side of a resin layer A containing an olefin resin as a main component. As a result, while having flexibility, it has excellent toughness, scratch resistance and transparency, and since it eliminates adhesion troubles between films, it is suitable for use as a covering material for agriculture such as houses and tunnels. You can

[0034]

[Table 1]

[0035]

[Table 2]

[0036]

[Table 3]

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Claims (3)

[Claims] 1. A laminated film for agriculture, wherein a resin layer B made of an olefin polymer composition containing 5 to 40% by weight of a hydrogenated diene copolymer is laminated on at least one surface of the resin layer A. 2. The resin layer A is a layer containing an olefin polymer as a main component, and the resin layer B contains an inorganic filler in an amount of 0.5 to 20.
The agricultural laminated film according to claim 1, wherein the film is a polypropylene polymer composition containing 2% by weight, and is 2 or more and 2 or more layers. 3. The inorganic filler mainly contains either hydrotalcites represented by the following general formula (1) or aluminum-lithium composite hydroxide salt represented by the general formula (2). The agricultural laminated film described. General formula (1) M ²⁺ _1-X Al _X (OH) ₂ (A ⁿ⁻ ) _{X / n} · mH ₂ O (wherein M ²⁺ is 2 selected from the group consisting of magnesium, calcium and zinc) Represents a valent metal ion, A ^n- represents an n-valent anion, _X and m are as follows, 0 < _X <
0.5, 0 ≦ m ≦ 2 is satisfied. ) General formula (2) [Al ₂ Li (OH) ₆ ] _n X · mH ₂ 0 (wherein, X is an inorganic or organic anion,
n is the valence of the anion X, and m is 3 or less. )