JP2020184956A - Agricultural resin film - Google Patents

Abstract

To provide an agricultural resin film which has good molding ability without an adhesive layer between resin layers, using a method such as surface processing or extrusion lamination, which facilitates peeling between a fluorine resin layer and a polyolefin-resin layer including no fluorine, which is excellent in anti fouling property, and which uses a fluorine resin.SOLUTION: An agricultural resin film 1 comprises a first layer 2 which is formed of a resin material including as a resin component, tetrafluoroethylene hexafluoropropylene vinylidene fluoride copolymer whose melting point is 200°C or smaller, and a second layer 3 which is formed of, as a resin component, polyolefin-resin material including ethylene-vinyl acetate copolymer in which vinyl acetate content is 10 mass% or greater, and which contacts the first layer 2.SELECTED DRAWING: Figure 1

Description

The present invention relates to an agricultural resin film used in an agricultural facility such as an agricultural house or an agricultural tunnel.

Generally, greenhouses, tunnels, etc. used in greenhouse cultivation, tunnel cultivation, etc. are made by coating a frame such as a metal pipe with an agricultural covering material such as a flexible resin film. As this agricultural coating material, for example, Patent Document 1 describes a composite agricultural coating made of a film having at least a fluororesin layer (A layer) and a resin layer (B layer) different from the previous A layer containing an antifogging agent. Materials have been proposed.

However, although the film described in Patent Document 1 has a fluororesin layer and is excellent in antifouling property, an ethylene-tetrafluoroethylene-based copolymer having a high melting point is used as the fluororesin, so that the film can be molded. There is a problem that the property is poor and it is difficult to multi-layer 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 laminating have been proposed (see, for example, Patent Documents 2 to 4).

Japanese Unexamined Patent Publication No. 7-1684 International Publication No. 2017/175824 Pamphlet Japanese Unexamined Patent Publication No. 2007-14205 Japanese Unexamined Patent Publication No. 9-076428

However, the above method has disadvantages such as poor film performance and difficulty in widening the film. In addition, it has been a factor that causes an increase in work man-hours and costs.

Therefore, the present invention has been made in view of the above problems, and has good moldability without providing an adhesive layer between resin layers or using methods such as surface processing and extrusion laminating, and the fluororesin layer and fluorine. It is an object of the present invention to provide an agricultural resin film using a fluororesin, which is hard to be peeled off from a polyolefin-based resin layer that does not contain

In order to achieve the above object, the agricultural resin film of the present invention is a first layer made of a resin material containing a tetrafluoroethylene / hexafluoropropylene / vinylidene fluoride copolymer having a melting point of 200 ° C. or lower as a resin component. A second layer made of a polyolefin-based resin material containing an ethylene-vinyl acetate copolymer having a vinyl acetate content of 10% by mass or more as a resin component is provided in contact with the first layer.

According to the present invention, the moldability is good and the fluororesin layer and the polyolefin-based resin layer containing no fluorine are peeled off without providing an adhesive layer between the resin layers or using a method such as surface processing or extrusion lamination. It is difficult and has excellent antifouling properties.

It is sectional drawing which shows the 1st Embodiment of the resin film for agriculture of this invention. It is sectional drawing which shows the 2nd Embodiment of the resin film for agriculture of this invention.

Hereinafter, the agricultural resin film according to the embodiment of the present invention will be described in detail with reference to the drawings. The following description of preferred embodiments is merely exemplary and is not intended to limit the present invention, its applications or its uses.

(First Embodiment)
(Agricultural resin film)
As shown in FIG. 1, the agricultural resin film 1 according to the present embodiment is a film having a two-layer structure including 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 it is expanded in an agricultural facility. Further, 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 made a layer having light transmission. Further, since the first layer 2 is a layer that suppresses a decrease in the amount of light transmission due to stains on the film during long-term stretching, it is a layer having antifouling properties.

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

The first layer 2 is preferably a layer made of a resin material containing a specific THV alone as a resin component (in other words, the resin component is only a specific THV).

The tetrafluoroethylene / hexafluoropropylene / vinylidene fluoride copolymer has a melting point as compared with other fluororesins (for example, ethylene-tetrafluoroethylene copolymer (ETFE), polyvinylidene fluoride (PVDF), etc.). Is low and flexible.

Among the tetrafluoroethylene / hexafluoropropylene / vinylidene fluoride copolymers, those having a melting point of 200 ° C. or lower (that is, a specific THV) are the first layer 2 and the second layer 3 (first layer). Unlike No. 2, it becomes difficult to peel off from the fluorine-free polyolefin resin layer). As a result, the moldability of the agricultural resin film 1 is improved, and the film 1 can be easily multi-layered. In addition, fluorine (F ₂ ) gas is unlikely to be generated during molding of the agricultural resin film 1 (for example, heat pressing, inflation molding, etc.). As a result, the corrosiveness to the equipment for producing the film 1 is suppressed, the influence on the operator is small, and the film 1 can be safely molded (the formability is good).

Further, among the specific THVs, those having a melting point of 150 ° C. or higher, that is, a tetrafluoroethylene / hexafluoropropylene / vinylidene fluoride copolymer having a melting point of 150 ° C. or higher and 200 ° C. or lower are preferable. When the melting point is 150 ° C. or higher, the stickiness of the agricultural resin film 1 is suppressed, and as a result, dirt is less likely to adhere to the film 1 and the film 1 is easily handled.

Further, the specific THV preferably has a melt mass flow rate (MFR) of 8 to 25 g / 10 minutes, and more preferably 8 to 15 g / 10 minutes. If the melt mass flow rate is within the above range, it can be extruded without any problem without overload in the extruder.

Further, the specific THV preferably has a density of 1.9 to 2.1 g / cm ³ or more, and more preferably 1.96 to 2.0 g / cm ³ or more. As a result, the stickiness of the agricultural resin film 1 is suppressed, and dirt is 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, tetrafluoroethylene / hexafluoropropylene other than the specific THV) as long as the above performance required for the first layer 2 is not impaired. -Vinylidene fluoride copolymer, polyvinylidene fluoride (PVDF), etc.), polyolefin resin, other known additives, etc. may be contained.

Examples of the additive include weather resistant agents such as hindered amine-based light stabilizers and ultraviolet absorbers, antioxidants, lubricants, antistatic agents, colorants, and the like, and in particular, agricultural resin films that can withstand long-term use. From the viewpoint of obtaining 1, it is preferable to have a weather resistant agent as an additive. Examples of the ultraviolet absorber include benzotriazole-based, benzophenone-based, and salicylic acid-based agents. The blending amount of the additive 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.

<2nd layer>
The second layer 3 is an inner layer facing the inside of the facility when it is extended to an agricultural facility, and is a layer in contact with the first layer 2. The second layer 3 is a layer that reinforces the first layer 2. The second layer 3 is a non-foaming layer.

Further, the second layer 3 is made into a flexible layer in order to supplement the flexibility of the first layer 2. Further, the second layer 3 is made into a layer having excellent interlayer adhesion with the first layer 2 in order to improve the moldability of the agricultural resin film 1.

In addition, in this specification, good moldability means that the layers between the first layer 2 and the second layer 3 are hard to be peeled off, and fluorine gas is hard to be generated at the time of molding of the agricultural resin film 1.

Here, in order to exhibit the above performance (strength, flexibility, moldability), 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. (Hereinafter, also referred to as "specific EVA") is formed into a layer made of a polyolefin resin material. In other words, the second layer 3 is a fluorine-free polyolefin resin layer.

Further, the second layer 3 is preferably a layer made of a resin material containing a specific EVA alone as a polyolefin-based resin component (in other words, the resin component is only the specific EVA).

The ethylene-vinyl acetate copolymer preferably has a vinyl acetate content of 10 to 30% by mass, and more preferably a vinyl acetate content of 10 to 25% by mass. When the vinyl acetate content is 10% by mass or more, the interlayer adhesive force with the first layer 2 is high, and the moldability of the agricultural resin film 1 is improved. When the vinyl acetate content is 30% by mass or less, the obtained agricultural resin film 1 is elastic, supple and durable, and therefore can be easily handled during stretching.

The ethylene-vinyl acetate copolymer preferably has a melting point of 100 ° C. or lower. When the melting point is 100 ° C. or lower, the 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, so that efficient production can be achieved. When 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 forming property is improved.

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

Further, the resin material constituting the second layer 3 may contain an anti-fog agent in order to impart anti-fog properties to the agricultural resin film 1. Examples of the antifogging agent include a partial ester of a polyhydric alcohol (sorbitan type, glycerin type, diglycerin type, etc.) and a fatty acid, or a condensate of these and an alkylene glycol. The amount of the antifogging agent blended 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.

Further, the resin material constituting the second layer 3 may contain a fluorine-based surfactant or a silicone-based surfactant together with the antifogging agent in order to impart antimist property to the agricultural resin film 1. ..

Further, the resin material constituting the second layer 3 may contain pigments such as titanium oxide pigment, carbon black pigment, and aluminum pigment as long as the above performance required for the second layer 3 is not impaired.

Further, the resin material constituting the second layer 3 is a polyolefin resin other than a specific EVA (for example, low density polyethylene (LDPE), linear low density) as long as the above performance required for the second layer 3 is not impaired. It may contain density polyethylene (LLDPE, etc.), other known additives, and the like. Examples of the additive include the same as above. The blending amount of the additive 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 constituting 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 the handling at the time of extension because the agricultural resin film 1 is elastic, supple and durable. ..

(Production method)
The agricultural resin film 1 can be produced, for example, by producing the films constituting the first layer and the second layer in advance, joining the two obtained films, and laminating them. Examples of the joining method include a hot pressing method, a hot embossing bonding method, a hot melt adhesive bonding, an ultrasonic bonding method, and a high frequency bonding method.

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

Examples of the coextrusion method of the molten resin constituting each layer include a pre-die lamination method in which the molten resin is brought into contact with the front of the die, an in-die lamination method in which the molten resin is brought into contact with the inside of the die, and a plurality of concentric lips of the die. Examples thereof include a die outer lamination method in which the resin is brought into contact after being discharged.

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 present invention will be described. FIG. 2 shows the agricultural resin film 10 according to the second embodiment. Since the overall configuration of the agricultural resin film 10 other than the third layer 4 described later is the same as that of the first embodiment, detailed description thereof will be omitted here. Further, the same components as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

In the present embodiment, the 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 on the side 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 layer (innermost layer) facing the inside of the facility when it is spread over the agricultural facility. Therefore, in the present embodiment, the second layer 3 is an intermediate layer provided between the first layer 2 and the third layer 4. As described above, as a result of the high interlayer adhesive strength between the first layer 2 and the second layer 3 and the ease of multi-layering of the film, the agricultural resin film 10 further has the third layer 4. It became possible.

The third layer 4 is a layer that reinforces the first layer 2 like the second layer 3. Further, 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 made a layer having light transmission.

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

Examples of the linear low-density polyethylene include linear low-density polyethylene produced by using a metallocene catalyst or a Ziegler catalyst. As this linear low-density polyethylene, a random copolymer of ethylene and α-olefin, a block copolymer, or the like can be used. Examples of the α-olefin include propylene, butene-1, 3-methylbutene-1, penten-1, 3-methylpentene-1, 4-methylpentene-1, hexene-1, octene-1, decene-1, and the like. Can be mentioned. The α-olefin may be used alone or in combination of two or more.

The 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, it can be extruded without any problem without overload in the extruder.

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

The linear low-density polyethylene preferably has a density of 0.91 g / cm ³ or more. As a result, the stickiness of the agricultural resin film 10 is suppressed, and dirt is less likely to adhere to the film 10. 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, and more preferably a vinyl acetate content of 10 to 25% by mass. When the vinyl acetate content is 5% by mass or more, the adhesion to the antifogging coating film is good. When the vinyl acetate content is 30% by mass or less, the obtained agricultural resin film 10 is elastic, supple and durable, so that it can be easily handled during stretching.

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, so that efficient production can be achieved. When 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 forming property is improved.

Examples of the low-density polyethylene include high-pressure low-density polyethylene and the like. The high-pressure low-density polyethylene preferably has a density of 0.935 g / cm ³ or less, it can be suitably used in 0.910 to 0.935 g / cm ^3.

Here, the third layer 4 may be a layer made of a polyolefin-based resin material containing linear low-density polyethylene as a resin component from the viewpoint of further improving the strength of the agricultural resin film 10, and may be a polyolefin-based layer. A layer made of a resin material containing 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 constituting the third layer 4 may contain an anti-fog agent in order to impart anti-fog properties to the agricultural resin film 10. Examples of the antifogging agent include the same as above. The amount of the antifogging agent blended 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 third layer 4.

Further, the resin material constituting the third layer 4 may contain a fluorine-based surfactant or a silicone-based surfactant together with the antifogging agent in order to impart antifog properties to the agricultural resin film 10. ..

Further, the resin material constituting the third layer 4 may contain other known additives and the like as long as the above performance required for the third layer 4 is not impaired. Examples of the additive include the same as above. The 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 the 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 50-99% of the total film.

(Production method)
The agricultural resin film 10 according to the present embodiment is preferably produced by an inflation method.

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

(Other embodiments)
The agricultural resin films 1 and 10 of the present invention are not limited to those shown in the illustrated examples. For example, in the second embodiment, the third layer 4 is composed of one layer, but two or more layers may be used. 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.

In each of the above embodiments, the first layer 2 and the third layer 4 are light-transmitting layers, but may not be light-transmitting layers.

In each of the above embodiments, the first layer, the second layer, and the third layer are all non-foaming 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 they are spread over 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 antifogging coating film may be provided. As a result, stable antifogging properties can be imparted to the films 1 and 10.

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

Next, using a heating 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. : Under the condition of 80 μm, the two resin films obtained above were stacked and hot pressed. As a result, an agricultural resin film having a first layer and a second layer adhered to the first layer was produced. Two types of two-layer agricultural resin films having a thickness of the first layer: 40 μm, a thickness of the second layer: 40 μm, and a total thickness of 80 μm were produced.

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

(Delamination)
From the film obtained in Example 1, a rectangular test piece for a delamination test having a width of 10 mm and a length of 100 mm was collected. Next, the above test piece was accurately attached to a precision universal testing machine [manufactured by Shimadzu Corporation, product number: Autograph AG-500D]. The test speed was 200 ± 20 mm per minute, and the test piece was stretched to a width of 5 mm, and the presence or absence of peeling 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 breakage (for example, tearing, tearing, etc.) of the test piece other than delamination is visually confirmed, and those without breakage are regarded as excellent in strength (○), and those with breakage are strong. Was evaluated as insufficient (x). The results are shown in Table 1.

(Moldability)
In the delamination test, those in which delamination is not confirmed between the first layer and the second layer and in which there is no risk of fluorine gas being generated during hot pressing are considered to have good moldability (◯), and the others are moldable. It was evaluated as inferior (x). The results are shown in Table 1.

(Anti-fouling property)
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 determined based on the following evaluation criteria. evaluated. The observation surface was the surface of the first layer. The results are shown in Table 1.
(Evaluation criteria)
◯: Not much different from the initial state of exposure (no dust adhered).
Δ: A little dust is attached.
X: Dust is remarkably attached.

(Sticky)
The friction coefficient test of the film obtained in Example 1 was carried out 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, a square sliding piece having a contact area of 40 cm ² (side length: 63 mm) is used, and the surfaces of the first layer of the two test pieces are brought into contact with each other. The static friction force was measured. The results are shown in Table 1. A friction and wear tester [manufactured by Shinto Kagaku Co., Ltd., product number: HEIDON TYPE 40] was used as the apparatus.
(Evaluation criteria)
No stickiness: The static friction force is less than 2 kgf.
Sticky: The 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 described 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. The results are shown in Table 1.

Each resin component shown in Table 1 is as follows.
(Fluororesin)
THV1: MFR 20g / 10min, melting point 120 ° C., density 1.95g / cm ³ [manufactured by 3M Japan Ltd., product number: THV 221GZ]
THV2: MFR 10g / 10min, melting point 165 ° C, density 1.98g / cm ³ [manufactured by 3M Japan Ltd., product number: THV 500GZ]
THV3: MFR 12g / 10min, melting point 225 ° C, density 2.06g / 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 minutes, melting point 105 ° C., density 0.93 g / cm ³ [manufactured by NUC Co., Ltd., product number: NUC-3223]
EVA15: Ethylene-vinyl acetate copolymer having a vinyl acetate unit content of 15% by weight, MFR 1.1 g / 10 minutes, melting point 90 ° C., density 0.94 g / cm ³ [manufactured by NUC Co., Ltd., product number: NUC-8452D]
EVA20: Ethylene-vinyl acetate copolymer having a vinyl acetate unit content of 20% by weight, MFR 1.5 g / 10 minutes, melting point 92 ° C., density 0.94 g / cm ³ [manufactured by Toso Co., Ltd., product number: Ultosen 631]
LDPE: High-pressure method low-density polyethylene, MFR 0.7 g / 10 min, melting point 110 ° C., density 0.919 g / cm ³ [manufactured by NUC Co., Ltd., 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 Corporation, product number: UF332]

(Example 4)
<Manufacturing of film>
First, a resin material composed of each resin component of Example 4 shown in Table 1 was prepared. Next, using a three-kind three-layer inflation device, 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 inside of the concentric circle of the die. The constituent resin material was co-extruded in a molten state, expanded from the inside by the pressure of air, cooled, and wound up. As a result, three types of three-layer agricultural resin films having 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 were produced. ..

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

The moldability is good (◯) when the delamination test does not confirm the delamination between the first layer and the second layer and there is no risk of fluorine gas being generated during inflation molding. Other than that, it was evaluated as inferior in moldability (x).

(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 evaluation of the film was evaluated. I did. The results are shown in Table 2.

The resin components shown in Table 2 are the same as 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 is in contact with the first layer. Since the layer is made of a polyolefin-based 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 (fluorine resin layer) and the second layer (fluorine) It can be seen that it is difficult to peel off from the polyolefin-based 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 structure agricultural resin film, Examples 1 to 3 have better moldability than Comparative Examples 1 to 5, and the first layer and the first layer have better moldability. It can be seen that the two layers are difficult to peel off. Further, it can be seen that Examples 1 to 3 are superior in antifouling property as compared with Comparative Example 6 in which the first layer is made of high-pressure low-density polyethylene.

Further, as shown in Table 2, in the agricultural resin film having a three-layer structure, Examples 4 and 5 have higher antifouling properties than Comparative Example 7 in which the first layer is made of linear low-density polyethylene. It turns out to be excellent.

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. You can see that.

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

1,10 Agricultural resin film 2 1st layer 3 2nd layer 4 3rd layer

Claims (2)

A first layer made of a resin material containing a tetrafluoroethylene / hexafluoropropylene / vinylidene fluoride copolymer having a melting point of 200 ° C. or lower as a resin component, and
An agricultural resin which is in contact with the first layer and includes a second layer made of a polyolefin-based 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 third layer of the second layer, which 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, is provided. The agricultural resin film according to 1.

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