JP2022180493A - agricultural resin film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an agricultural resin film using fluorine resin, which has favorable moldability even if no adhesive layer is disposed between resin layers, or methods such as surface processing and extrusion laminating are not used, which has excellent antifouling properties, and in which a fluorine resin layer and a polyolefin resin layer containing no fluorine are difficult to be peeled off from each other.

SOLUTION: An agricultural resin film 1 comprises: a first layer 2 made of a resin material containing a fluorine resin with a melting point of 200°C or lower and an MFR of 8-25 g/10 min, or a fluorine resin with a density of 1.9 g/cm³ or more as a resin component; and a second layer 3 being in contact with the first layer 2, which is made of a polyolefin resin material containing an ethylene-vinyl acetate copolymer containing with a vinyl acetate content of 10 wt.% or more as a resin component.

SELECTED DRAWING: Figure 1

COPYRIGHT: (C)2023,JPO&INPIT

Description

TECHNICAL FIELD The present invention relates to an agricultural resin film used in agricultural facilities such as agricultural houses and agricultural tunnels.

Generally, greenhouses, tunnels, and the like used for greenhouse cultivation, tunnel cultivation, and the like are made by covering frameworks such as metal pipes with agricultural covering materials such as flexible resin films. As this agricultural coating material, for example, Patent Document 1 discloses a composite agricultural coating made of a film having at least a fluororesin layer (A layer) and a resin layer (B layer) containing an antifogging agent and different from the A layer. materials are suggested.

However, since the film described in Patent Document 1 has a fluororesin layer, it has excellent antifouling properties, but since an ethylene-tetrafluoroethylene copolymer with a high melting point is used as the fluororesin, it is difficult to form the film. There is a problem that it is difficult to laminate the fluororesin layer and a resin layer different from the fluororesin layer.

Therefore, methods such as providing an adhesive layer between resin layers, surface processing, and extrusion lamination have been proposed (see, for example, Patent Documents 2 to 4).

JP-A-7-1684 International Publication No. 2017/175824 pamphlet JP 2007-145025 A JP-A-9-076428

However, the above method has disadvantages such as deterioration in film performance and difficulty in widening the film. Moreover, it was a factor causing an increase in work man-hours and costs.

Accordingly, the present invention has been made in view of the above-mentioned problems, and provides good moldability without using an adhesive layer between resin layers, surface processing, extrusion lamination, etc. An object of the present invention is to provide an agricultural resin film using a fluororesin that is difficult to separate from a polyolefin resin layer that does not contain a fluororesin and has excellent antifouling properties.

In order to achieve the above object, the agricultural resin film of the present invention comprises, as a resin component, a fluororesin having a melting point of 200° C. or less and an MFR of 8 to 25 g/10 min or a density of 1.9 g/cm ³ or more. and a polyolefin resin material that is in contact with the first layer and contains, as a resin component, an ethylene-vinyl acetate copolymer having a vinyl acetate content of 10% by mass or more. and a second layer.

According to the present invention, moldability is good and the fluororesin layer and the fluorine-free polyolefin resin layer can be separated from each other without providing an adhesive layer between resin layers, surface processing, extrusion lamination, or other methods. It is difficult to clean and has excellent antifouling properties.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows 1st Embodiment of the agricultural resin film of this invention. Fig. 2 is a cross-sectional view showing a second embodiment of the agricultural resin film of the present invention;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, agricultural resin films according to embodiments of the present invention will be described in detail based on the drawings. The following description of preferred embodiments is merely exemplary in nature and is in no way intended to limit the invention, its applicability or its uses.

(First embodiment)
(Agricultural resin film)
As shown in FIG. 1 , the agricultural resin film 1 according to this embodiment is a two-layer film having a first layer 2 and a second layer 3 .

<First layer>
The first layer 2 is an outer surface layer (outermost layer) facing the side exposed to sunlight, that is, the outside of the facility when installed in an agricultural facility. Moreover, since the first layer 2 is a layer that protects the second layer 3 without interfering with the function of the second layer 3, it is a layer having optical transparency. In addition, the first layer 2 is a layer that suppresses a decrease in light transmittance due to contamination of the film during long-term stretching, so it is a layer having antifouling properties.

Here, the first layer 2 is a tetrafluoroethylene/hexafluoropropylene/vinylidene fluoride copolymer having a melting point of 200° C. or less as a resin component in order to exhibit the above performance (light transmittance, antifouling property). (THV) (hereinafter also referred to as “specific THV”).

It should be noted that the first layer 2 is preferably a layer made of a resin material that contains the specific THV alone as a resin component (in other words, the resin component is only the specific THV).

Tetrafluoroethylene/hexafluoropropylene/vinylidene fluoride copolymer has a lower melting point than other fluororesins (e.g., ethylene-tetrafluoroethylene copolymer (ETFE), polyvinylidene fluoride (PVDF), etc.). low and high flexibility.

Among these tetrafluoroethylene/hexafluoropropylene/vinylidene fluoride copolymers, if the melting point is 200° C. or less (that is, a specific THV), the first layer 2 and the second layer 3 (first layer 2, it becomes difficult to separate from the polyolefin resin layer containing no fluorine). As a result, the formability of the agricultural resin film 1 is improved, and the multi-layering of the film 1 is facilitated. In addition, fluorine (F ₂ ) gas is less likely to be generated during molding of the agricultural resin film 1 (for example, hot press, inflation molding, etc.). As a result, corrosiveness to equipment for manufacturing the film 1 can be suppressed, and the film 1 can be safely formed (good formability) with little effect on workers.

Among specific THVs, those having a melting point of 150° C. or higher, that is, tetrafluoroethylene/hexafluoropropylene/vinylidene fluoride copolymers having a melting point of 150° C. or higher and 200° C. or lower are preferred. If the melting point is 150° C. or higher, stickiness of the agricultural resin film 1 is suppressed, and as a result, the film 1 is less likely to be soiled, and the film 1 is easier to handle.

The specific THV preferably has a melt mass flow rate (MFR) of 8 to 25 g/10 minutes, more preferably 8 to 15 g/10 minutes. If the melt mass flow rate is within the above range, the extruder can be extruded without problems such as overloading.

The specific THV preferably has a density of 1.9 to 2.1 g/cm ³ , more preferably 1.96 to 2.0 g/cm ³ . As a result, stickiness of the agricultural resin film 1 is suppressed, and stains are less likely to adhere to the film 1 .

The resin material constituting the first layer 2 is a fluororesin other than a specific THV (for example, a tetrafluoroethylene/hexafluoropropylene - A vinylidene fluoride copolymer, polyvinylidene fluoride (PVDF), etc.), a polyolefin resin, other known additives, and the like may be included.

Examples of additives include weathering agents such as hindered amine light stabilizers and ultraviolet absorbers, antioxidants, lubricants, antistatic agents, colorants, etc. In particular, agricultural resin films that can withstand long-term use. From the viewpoint of obtaining 1, it is preferable to have a weather resistance agent as an additive. Examples of ultraviolet absorbers include benzotriazole-based, benzophenone-based, and salicylic acid-based ones. The amount of the additive compounded is, for example, 0.05 to 1 part by mass with respect to 100 parts by mass of the resin component of the first layer 2 .

The thickness of the first layer 2 is preferably 1 to 50% of the thickness of the entire film from the viewpoint of reducing the weight of the film and improving the spreading workability.

<Second layer>
The second layer 3 is an inner surface layer that faces the inside of the facility when installed in an agricultural facility, and is a layer in contact with the first layer 2 . This second layer 3 is a layer that reinforces the first layer 2 . In addition, the second layer 3 is a non-foaming layer.

Also, the second layer 3 is a flexible layer in order to compensate for the flexibility of the first layer 2 . Also, the second layer 3 is a layer having excellent interlaminar adhesive strength with the first layer 2 in order to improve the moldability of the agricultural resin film 1 .

In this specification, good formability means that the first layer 2 and the second layer 3 are not easily separated from each other and fluorine gas is not easily generated when the agricultural resin film 1 is molded.

Here, the second layer 3 is an ethylene-vinyl acetate copolymer (EVA) having a vinyl acetate content of 10% by mass or more as a resin component in order to develop the above performance (strength, flexibility, moldability). (hereinafter also referred to as “specific EVA”). In other words, the second layer 3 is a polyolefin resin layer containing no fluorine.

Moreover, the second layer 3 is preferably a layer made of a resin material that contains specific EVA alone as a polyolefin resin component (in other words, the resin component is only specific EVA).

The ethylene-vinyl acetate copolymer preferably has a vinyl acetate content of 10 to 30% by mass, more preferably 10 to 25% by mass. When the vinyl acetate content is 10% by mass or more, the interlayer adhesive strength with the first layer 2 is high, and the formability of the agricultural resin film 1 is improved. If the vinyl acetate content is 30% by mass or less, the resulting agricultural resin film 1 is stiff, supple, and strong, so that it can be handled well when stretched.

Also, the ethylene-vinyl acetate copolymer preferably has a melting point of 100° C. or less. If the melting point is 100° C. or less, moldability is good.

The ethylene-vinyl acetate copolymer preferably has a melt mass flow rate of 0.4 to 10 g/10 minutes. If the melt mass flow rate is 0.4 g/10 minutes or more, the molding speed can be increased, and efficient production can be achieved. If the melt mass flow rate is 10 g/10 minutes or less, the shape of the agricultural resin film 1 is maintained and the film formability is improved.

The resin material forming the second layer 3 may contain a heat retaining agent (far-infrared absorbing agent) from the viewpoint of enhancing heat retention. Examples of heat insulating agents include hydrotalcite compounds, inorganic oxides, inorganic hydroxides, and the like. From the viewpoint of improving heat retention while maintaining the strength of the agricultural resin film 1, the blending amount of the heat retaining agent is preferably 1 to 20 parts per 100 parts by mass of the resin component of each layer constituting the second layer 3. parts by mass, more preferably 3 to 10 parts by mass.

Moreover, the resin material constituting the second layer 3 may contain an antifogging agent in order to impart an antifogging property to the agricultural resin film 1 . Antifog agents include, for example, partial esters of polyhydric alcohols (sorbitan-based, glycerin-based, diglycerin-based, etc.) and fatty acids, or condensates of these with alkylene glycol. The amount of the antifogging agent to be added is preferably 1 to 5 parts by mass, more preferably 1.2 to 3 parts by mass, based on 100 parts by mass of the resin component of the second layer 3 .

In addition, the resin material constituting the second layer 3 may contain a fluorine-based surfactant or a silicone-based surfactant together with an anti-fogging agent in order to impart anti-fogging properties to the agricultural resin film 1. .

The resin material forming the second layer 3 may contain pigments such as titanium oxide pigments, carbon black pigments, and aluminum pigments within a range that does not impair the performance required of the second layer 3 .

In addition, the resin material constituting the second layer 3 is a polyolefin resin other than specific EVA (for example, low density polyethylene (LDPE), linear low density polyethylene (LLDPE), other known additives, and the like. Examples of the additive include those similar to those described above. The amount of the additive compounded is not particularly limited, and is, for example, 0.05 to 1 part by mass with respect to 100 parts by mass of the resin component forming the second layer 3 .

The thickness of the second layer 3 is preferably 50 to 99% of the thickness of the entire film from the viewpoint of improving handling when stretched because the agricultural resin film 1 is stiff, flexible and strong. .

(Production method)
The agricultural resin film 1 can be manufactured, for example, by manufacturing films constituting the first layer and the second layer in advance, and bonding and laminating the obtained two films. The bonding method includes, for example, a heat press method, a heat embossing bonding method, bonding using a hot melt adhesive, an ultrasonic bonding method, a high frequency bonding method, and the like.

Moreover, the agricultural resin film 1 can also be manufactured by the inflation method. Specifically, each resin material in a molten state constituting the first layer and the second layer is co-extruded from a die into a tubular shape, expanded from the inside by air pressure, and then cooled to form an agricultural resin film. 1 can be manufactured.

Examples of methods for co-extrusion of the molten resins that make up each layer include a pre-die lamination method in which the molten resins are brought into contact before the die, an in-die lamination method in which the molten resins are brought into contact inside the die, and a plurality of concentric lips of the die. A die-outside lamination method of contacting after discharging may be mentioned.

The thickness of the obtained agricultural resin film 1 (total thickness of the first layer and the second layer) is preferably 50 to 400 μm from the viewpoint of strength and handleability.

(Second embodiment)
Next, a second embodiment of the invention will be described. FIG. 2 shows an agricultural resin film 10 according to a second embodiment. The overall configuration of the agricultural resin film 10 other than the third layer 4 to be described later is the same as that of the first embodiment, so detailed description is omitted here. Also, the same reference numerals are assigned to the same components as in the first embodiment, and the description thereof will be omitted.

In this embodiment, a third layer 4 made of a resin material containing linear low-density polyethylene as a resin component is laminated on the surface of the second layer 3 opposite to the side in contact with the first layer 2. It is characterized by points.

<Third layer>
The third layer 4 is an inner surface layer (innermost layer) facing the inside of the facility when installed in the facility. Therefore, in this embodiment, the second layer 3 is an intermediate layer provided between the first layer 2 and the third layer 4 . As described above, the interlayer adhesion between the first layer 2 and the second layer 3 is high, and the film can be easily formed into multiple layers. As a result, the agricultural resin film 10 further has the third layer 4. became possible.

This third layer 4 is a layer that reinforces the first layer 2 like the second layer 3 . Moreover, since the third layer 4 is a layer that protects the second layer 3 without interfering with the function of the second layer 3, it is a layer having light transmission properties.

Examples of the polyolefin-based resin contained in the resin material forming the third layer 4 include linear low-density polyethylene, ethylene-vinyl acetate copolymer, and low-density polyethylene. These polyolefin resins may be used alone or in combination of two or more.

Linear low-density polyethylenes include, for example, linear low-density polyethylenes produced using metallocene catalysts or Ziegler catalysts. A random copolymer or a block copolymer of ethylene and α-olefin can be used as the linear low-density polyethylene. Examples of α-olefins include propylene, butene-1, 3-methylbutene-1, pentene-1, 3-methylpentene-1, 4-methylpentene-1, hexene-1, octene-1, decene-1, and the like. is mentioned. The α-olefins may be used singly or in combination of two or more.

This linear low-density polyethylene preferably has a melt mass flow rate of 0.2 g/10 minutes or more. If the melt mass flow rate is 0.2 g/10 minutes or more, there is no overload in the extruder and it is possible to extrude without problems.

Further, the linear low-density polyethylene preferably has a melting point of 100 to 150°C. If the melting point is 100 to 150° C., moldability is good.

Further, the linear low-density polyethylene preferably has a density of 0.91 g/cm ³ or more. As a result, stickiness of the agricultural resin film 10 is suppressed, and stains are less likely to adhere to the film 10 . Note that the upper limit of the density is 0.940 g/cm ³ or less from the viewpoint of improving transparency.

The ethylene-vinyl acetate copolymer preferably has a vinyl acetate content of 5 to 30% by mass, more preferably 10 to 25% by mass. If the vinyl acetate content is 5% by mass or more, the adhesiveness to the antifogging coating film is good. If the vinyl acetate content is 30% by mass or less, the resulting agricultural resin film 10 is stiff, supple, and strong, so that it can be handled well when stretched.

The ethylene-vinyl acetate copolymer preferably has a melt mass flow rate of 0.4 to 10 g/10 minutes. If the melt mass flow rate is 0.4 g/10 minutes or more, the molding speed can be increased, and efficient production can be achieved. If the melt mass flow rate is 10 g/10 minutes or less, the shape of the agricultural resin film 10 is maintained and the film formability is improved.

Examples of low-density polyethylene include high-pressure low-density polyethylene. The high-pressure low-density polyethylene preferably has a density of 0.935 g/cm ³ or less, and preferably from 0.910 to 0.935 g/cm ³ .

Here, from the viewpoint of further improving the strength of the agricultural resin film 10, the third layer 4 may be a layer made of a polyolefin-based resin material containing linear low-density polyethylene as a resin component. A layer made of a resin material that contains linear low-density polyethylene alone as a resin component (in other words, the resin component is only linear low-density polyethylene) may be used.

The resin material forming the third layer 4 may contain an antifogging agent in order to impart antifogging properties to the agricultural resin film 10 . Examples of the antifogging agent include those similar to those described above. The amount of the anti-fogging agent compounded is preferably 1 to 5 parts by mass, more preferably 1.2 to 3 parts by mass, with respect to 100 parts by mass of the resin component of the third layer 4 .

In addition, the resin material constituting the third layer 4 may contain a fluorine-based surfactant or a silicone-based surfactant together with an anti-fogging agent in order to impart anti-fogging properties to the agricultural resin film 10. .

In addition, the resin material forming the third layer 4 may contain other known additives and the like within a range that does not impair the performance required of the third layer 4 . Examples of the additive include those similar to those described above. A blending amount of the additive is, for example, 0.01 to 20 parts by mass with respect to 100 parts by mass of the resin component of the third layer 4 .

In the present embodiment, from the viewpoint of improving moldability in inflation molding, the thickness of the first layer 2 is 1 to 50% of the entire film, and the total thickness of the second layer 3 and the third layer 4 is , preferably 50 to 99% of the entire film.

(Production method)
The agricultural resin film 10 according to this embodiment is preferably manufactured by the inflation method.

The thickness of the obtained agricultural resin film 10 is preferably 50 to 400 μm in terms of strength and handleability.

(Other embodiments)
The agricultural resin films 1 and 10 of the present invention are not limited to the illustrated examples. For example, although the third layer 4 is composed of one layer in the second embodiment, it may be composed of two or more layers. When the third layer is composed of two or more layers, at least one of the third layers may be composed of a layer made of a resin material containing linear low-density polyethylene as a resin component.

Although the first layer 2 and the third layer 4 are light-transmitting layers in each of the above-described embodiments, they may not be light-transmitting layers.

In each of the above embodiments, the first, second, and third layers are all non-foamed layers, but the second layer 3 may be a layer (foamed layer) formed by foaming a resin material.

Further, in the agricultural resin films 1 and 10 of the present invention, when installed in an agricultural facility, the surface of the innermost layer facing the innermost side of the facility is composed of a thermoplastic resin binder and an inorganic colloid sol. An anti-fogging coating may be provided. Thereby, the films 1 and 10 can be provided with stable antifogging properties.

(Example 1)
<Film production>
First, using each resin component shown in Table 1, films constituting the first layer and the second layer of Example 1 were produced. More specifically, using an inflation device, each resin material is co-extruded in a molten state from the concentric lips of a die, expanded from the inside by air pressure, cooled, wound up, and formed into a single layer. A resin film was used.

Next, using a heat press machine [manufactured by Kodaira Seisakusho Co., Ltd., product number: PY-125], temperature: 250° C., pressure: 50 kg/cm ² , time: 5 minutes, length: 100 mm, width: 100 mm, thickness : The two resin films obtained above were superimposed and hot-pressed under the conditions of 80 μm. This produced an agricultural resin film having a first layer and a second layer adhered to the first layer. Two types of two-layer agricultural resin films were produced with a first layer thickness of 40 μm, a second layer thickness of 40 μm, and a total thickness of 80 μm.

<Evaluation of film>
The performance of the agricultural resin film of Example 1 obtained above (hereinafter also simply referred to as film) was evaluated based on the following methods.

(delamination)
From the film obtained in Example 1, a rectangular delamination test piece having a width of 10 mm and a length of 100 mm was taken. Next, the above test piece was accurately attached to a precision universal testing machine (manufactured by Shimadzu Corporation, product number: Autograph AG-500D). At a test speed of 200±20 mm/min, the test piece was stretched to a width of 5 mm, and the presence or absence of delamination between the first layer and the second layer of the stretched test piece was visually confirmed.

(Strength)
In the delamination test, the presence or absence of damage (e.g., tearing, tearing, etc.) of the test piece other than delamination is visually confirmed, and those without damage are evaluated as having excellent strength (○), and those with damage are strong. was evaluated as insufficient (x). Table 1 shows the results.

(Moldability)
In the above delamination test, if no delamination is confirmed between the first layer and the second layer and there is no possibility of fluorine gas being generated during hot pressing, the formability is good (○), and other than that, the formability is good. It was evaluated as inferior (×). Table 1 shows the results.

(Anti-fouling)
The film obtained in Example 1 was confirmed by actual exposure. More specifically, the film was exposed on an outdoor exposure table at an angle of 20 degrees for 12 months, the appearance of the film after exposure was visually confirmed, and the antifouling property of the film was evaluated based on the following evaluation criteria. evaluated. The observation surface was the surface of the first layer. Table 1 shows the results.
(Evaluation criteria)
◯: Not much different from the initial state of exposure (no dust adhered).
Δ: A little dust is adhered.
x: Dust adheres remarkably.

(stickiness)
The film obtained in Example 1 was subjected to a friction coefficient test according to JIS K 7125, the static friction force was measured, and the stickiness of the film was evaluated based on the following evaluation criteria. More specifically, the size of the test piece is 80 × 200 mm, and the contact area is 40 cm ² (length of one side: 63 mm). Static friction force was measured. Table 1 shows the results. A friction and wear tester [product number: HEIDON TYPE 40, manufactured by Shinto Kagaku Co., Ltd.] was used as an apparatus.
(Evaluation criteria)
No stickiness: The static friction force is less than 2 kgf.
Stickiness: Static friction force is 2 kgf or more.

(Examples 2 and 3, and Comparative Examples 1 to 6)
An agricultural resin film was produced in the same manner as in Example 1 above, except that each resin component was changed to the resin components of Examples 2, 3, and Comparative Examples 1 to 6 shown in Table 1, The film was evaluated. Table 1 shows the results.

Each resin component described in Table 1 is as follows.
(fluororesin)
THV1: MFR 20 g/10 min, melting point 120° C., density 1.95 g/cm ³ [manufactured by 3M Japan Ltd., product number: THV 221GZ]
THV2: MFR 10 g/10 min, melting point 165° C., density 1.98 g/cm ³ [manufactured by 3M Japan Limited, product number: THV 500GZ]
THV3: MFR 12 g/10 min, melting point 225° C., density 2.06 g/cm ³ [manufactured by 3M Japan Ltd., product number: THV 815GZ]
ETFE: MFR 11 g/10 min, melting point 255° C., density 1.77 g/cm ³ [manufactured by Daikin Industries, Ltd., product number: EP-526]
(polyolefin resin)
EVA5: ethylene-vinyl acetate copolymer having a vinyl acetate unit content of 5% by weight, MFR 1.4 g/10 min, melting point 105°C, density 0.93 g/cm ³ [manufactured by NUC Corporation, part number: NUC-3223]
EVA15: Ethylene-vinyl acetate copolymer having a vinyl acetate unit content of 15% by weight, MFR 1.1 g/10 min, melting point 90°C, density 0.94 g/cm ³ [manufactured by NUC Corporation, product number: NUC-8452D]
EVA20: Ethylene-vinyl acetate copolymer having a vinyl acetate unit content of 20% by weight, MFR 1.5 g/10 min, melting point 92°C, density 0.94 g/cm ³ [manufactured by Tosoh Corporation, product number: Wurtocene 631]
LDPE: high-pressure low-density polyethylene, MFR 0.7 g/10 min, melting point 110° C., density 0.919 g/cm ³ [manufactured by NUC Corporation, product number: NUC-8323]
LLDPE: linear low-density polyethylene, MFR 1.0 g/10 min, melting point 122° C., density 0.923 g/cm ³ [manufactured by Japan Polyethylene Co., Ltd., product number: UF332]

(Example 4)
<Film production>
First, a resin material composed of each resin component of Example 4 shown in Table 1 was prepared. Next, using an inflation device of 3 types and 3 layers, each of the above layers is formed from a plurality of concentric lips of the die so as to form the first layer, the second layer and the third layer in order from the concentric inner side of the die. The constituent resin materials were co-extruded in a molten state, expanded from the inside by air pressure, cooled, and wound up. As a result, three types of three-layer agricultural resin films were produced, with a thickness of the first layer: 30 μm, a thickness of the second layer: 30 μm, a thickness of the third layer: 90 μm, and a total thickness of 150 μm. .

<Evaluation of film>
The performance of the agricultural resin film of Example 4 obtained above (hereinafter also simply referred to as film) was evaluated in the same manner as in Example 1 above. Table 2 shows the results.

In terms of formability, in the above delamination test, delamination between the first layer and the second layer was not confirmed, and when there was no possibility of generating fluorine gas during inflation molding, the formability was evaluated as good (○). , Other than that, it was evaluated as poor moldability (×).

(Example 5 and Comparative Example 7)
An agricultural resin film was produced in the same manner as in Example 4 above, except that each resin component was changed to the resin component of Example 5 and Comparative Example 7 shown in Table 2, and the film was evaluated. did. Table 2 shows the results.

In addition, each resin component described in Table 2 is the same as the above.

As shown in Tables 1 and 2, in each of the agricultural resin films of Examples 1 to 5, the first layer is made of a resin material containing a specific THV as a resin component, and the second layer in contact with the first layer Since the layer is made of a polyolefin resin material containing a specific EVA as a resin component, it has better moldability than the films of Comparative Examples 1 to 7, and the first layer (fluororesin layer) and the second layer (fluorine It can be seen that it is difficult to peel off from the polyolefin resin layer that does not contain it, and that it has excellent antifouling properties.

More specifically, as shown in Table 1, in the two-layer agricultural resin film, Examples 1 to 3 have better moldability than Comparative Examples 1 to 5, and the first layer and the first layer It can be seen that the two layers are difficult to separate. Moreover, it can be seen that Examples 1 to 3 are superior in antifouling property to Comparative Example 6, in which the first layer is made of high-pressure low-density polyethylene.

In addition, as shown in Table 2, in the three-layered agricultural resin film, Examples 4 and 5 have better antifouling properties than Comparative Example 7 in which the first layer is made of linear low-density polyethylene. I know it's good.

In Examples 2 to 4, since the first layer is made of a resin material containing a tetrafluoroethylene/hexafluoropropylene/vinylidene fluoride copolymer having a melting point of 150° C. or higher and 200° C. or lower, stickiness of the film is suppressed. It is understood that

As explained above, the present invention is suitable for agricultural resin films.

1, 10 agricultural resin film 2 first layer 3 second layer 4 third layer

Claims (3)

a first layer made of a resin material containing a fluororesin having a melting point of 200° C. or less and an MFR of 8 to 25 g/10 min as a resin component;
An agricultural resin characterized by comprising a second layer, which is in contact with the first layer and is made of a polyolefin resin material containing an ethylene-vinyl acetate copolymer having a vinyl acetate content of 10% by mass or more as a resin component. the film. a first layer made of a resin material containing a fluororesin having a melting point of 200° C. or less and a density of 1.9 g/cm ³ or more as a resin component;
An agricultural resin characterized by comprising a second layer, which is in contact with the first layer and made of a polyolefin resin material containing an ethylene-vinyl acetate copolymer having a vinyl acetate content of 10% by mass or more as a resin component. the film. 3. The third layer is laminated on the surface of the second layer opposite to the side in contact with the first layer and is made of a resin material containing linear low-density polyethylene as a resin component. 3. The agricultural resin film according to 1 or 2.

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