JP7084869B2 - Fluorine-containing laminated film for agriculture and agricultural coating materials using it - Google Patents

Description

The present invention relates to an agricultural fluorine-containing laminated film having optical properties equivalent to those of a conventional fluorine-based resin film and particularly excellent in drip sustainability.

Traditionally, as the main covering material for facility gardening such as green houses, agricultural polyvinyl chloride (agricultural vinyl) film using polyvinyl chloride resin, agriculture using low density polyethylene resin and ethylene vinyl acetate copolymer resin Polyolefin-based (agricultural PVC) film for use is used.

However, since the agricultural bifilm is easily contaminated by the plasticizer and the transmittance is easily lowered, the stretching period is extremely short, and the agricultural PO film has a longer-term stretching property than the agricultural bifilm, but is re-covered in about 5 years.

In addition, the inside of the green house is generally hot and humid, and water droplets and cloudiness are likely to occur inside the film, which reduces the transmittance of the sun's rays and may adversely affect the growth of plants. Therefore, in any film, it is necessary to perform a drop treatment on the inside of the film.

For example, Patent Document 1 describes an anti-fog composition containing inorganic particles composed of an alumina sol and a silica sol, a surfactant and the like, and the anti-fog composition is applied to the surface of a thermoplastic resin which is a base material of an agricultural film, for example. It has been proposed to form a coating film having anti-fog properties by drying.

Patent Document 2 proposes an agricultural laminated film having the effect of preventing water droplets from adhering in addition to long-term stretchability by laminating a fluorine-containing copolymer film having hydrophilicity on the inner surface side of a fluororesin-based film. Has been done.

Japanese Unexamined Patent Publication No. 60-69181 Japanese Unexamined Patent Publication No. 7-117188

However, in the coating film obtained in Patent Document 1, since the alumina particles and the silica particles are adhered to the substrate by the surfactant, the adhesion between the substrate and the inorganic particles is not always good. There was a problem of lack of durability.

Further, even on the surface of the hydrophilic fluorine-containing copolymer film obtained in Patent Document 2, the static contact angle of water is still large due to the influence of fluorine atoms, and water droplets generated by dew condensation adhere to the inner surface of the film for a long period of time. In some cases, the problem of water static was not always fully solved.

The present invention has been made in view of the above circumstances, and has the same level of weather resistance and long-term stretchability as a conventional fluororesin film, and maintains particularly excellent drip performance for a long period of time. It is an object of the present invention to provide an agricultural fluorine-containing film capable of being produced and an agricultural coating material using the same.

According to some aspects of the present invention, the thermoplastic resin layer is arranged on one surface of the fluororesin layer containing the ultraviolet blocking agent via the adhesive resin layer, and the thermoplastic resin layer is combined with the adhesive resin layer of the thermoplastic resin layer. An agricultural fluorine-containing laminated film comprising a drip layer containing a layered silicate, a polymer binder and a light stabilizer on opposite surfaces is provided.

When the present inventors diligently studied an agricultural film having excellent weather resistance and drip performance, a fluororesin layer having excellent weather resistance and a drip layer having excellent drip performance were formed through a thermoplastic resin layer. When adhered, it has been found that it can be used for a long period of time because it is hard to get dirty while maintaining good drip performance at the initial stage of expansion when used as a covering material for a green house, and the present invention has been completed.

Hereinafter, various embodiments of the present invention will be illustrated. The embodiments shown below can be combined with each other.

Preferably, the fluororesin layer contains an ultraviolet absorber.
Preferably, the film thickness of the drop layer is 0.2 to 0.8 μm.
Preferably, the static contact angle of water on the surface of the drop layer is 40 ° or less.
Preferably, the fluorine-based resin layer is a single layer or a multi-layer of two or more layers, and the single layer or the multi-layer of the two or more layers is a vinylidene fluoride-based resin and / or a polymethacrylic acid ester-based resin. include.

Alternatively, according to another aspect, an agricultural covering material using the above-mentioned fluorine-containing laminated film for agriculture is provided.

The present invention also provides an agricultural covering material using the agricultural fluorine-containing laminated film according to the present invention.

The fluorine-containing laminated film for agriculture of the present invention is a film that can be used as a coating material for a green house, etc., and is excellent in weather resistance and long-term stretchability, and is particularly a film capable of maintaining drip performance for a long period of time. However, the cost is lower than that of the conventional fluorine-based resin film.

It is a schematic diagram which shows the cross section of the fluorine-containing laminated film for agriculture which concerns on one Embodiment of this invention. It is a figure explaining the test method (in-house method) for evaluating the drip property using a water bath.

In the fluorine-containing laminated film for agriculture of the present invention, a thermoplastic resin layer is arranged on one surface of a fluororesin layer containing an ultraviolet blocking agent via an adhesive resin layer, and the thermoplastic resin layer and the adhesive resin layer of the thermoplastic resin layer are arranged. A drip layer containing a layered silicate, a polymer binder and a light stabilizer is provided on the opposing surface. That is, as shown in FIG. 1, the fluorine-containing laminated film 1 for agriculture according to the embodiment of the present invention includes a fluorine-based resin layer 3, an adhesive resin layer 5, a thermoplastic resin layer 7, and a drip layer 9. At least prepare. The adhesive resin layer 5 is provided between the fluororesin layer 3 and the thermoplastic resin layer 7, and the drip layer 9 is provided on a surface of the thermoplastic resin layer 7 that opposes the adhesive resin layer 5.
Hereinafter, embodiments of the present invention will be described in detail.

<Fluorine resin layer>
As a film for lamination capable of imparting stain resistance to an agricultural film, a film made of a fluorine-based resin is used as a fluorine-based resin layer. The fluorine-based resin constituting the fluorine-based resin layer is not particularly limited as long as it is a resin containing fluorine and having antifouling performance. For example, an ethylene-tetrafluoroethylene-based copolymer (ETFE) or an ethylene-chlorotri. Examples thereof include a fluoroethylene-based copolymer (ECTFE) and a polyvinylidene fluoride-based resin (PVDF). Of these, polyvinylidene fluoride-based resins are preferable from the viewpoints of melt fluidity, light transmittance of the film, and compatibility with other resins.

The polyvinylidene fluoride-based resin may be a homopolymer of vinylidene fluoride, or copolymerized with vinylidene fluoride as a main component and other fluorine-containing monomers as a monomer unit in a range of up to 50% by mass. It may be a copolymer. Examples of the fluorine-containing monomer forming a copolymer with vinylidene fluoride include known fluorine-containing monomers such as hexafluoropropylene, tetrafluoroethylene, hexafluoroisobutylene, and various fluoroalkylvinyl ethers, among which the flexibility is enhanced. Hexafluoropropylene is preferable as the fluorine-containing monomer to be copolymerized with vinylidene fluoride.

The fluororesin layer may contain a resin component other than the fluororesin. Among them, the polymethacrylic acid ester resin has excellent compatibility with the vinylidene fluoride resin, improves workability by lowering the extrusion temperature during film extrusion molding, and is used when laminating with other materials. It can be suitably used because it has an effect of improving the adhesiveness of the resin.

As the polymethacrylic acid ester-based resin, in addition to a homopolymer of methyl methacrylate (polymethylmethacrylate), acrylic acid ester containing methyl methacrylate as a main component and less than 50% by mass of methacrylic acid ester other than methyl methacrylate. Examples thereof include copolymers contained therein, and mixtures of two or more of these polymers. Examples of the acrylic acid ester include methyl acrylate, ethyl acrylate, propyl acrylate and butyl acrylate, and examples of the methacrylic acid ester other than methyl methacrylate include ethyl methacrylate and propyl methacrylate. can. Further, the copolymer is not limited to a random copolymer, and for example, a graft copolymer or the like is also used, and a copolymer obtained by graft-polymerizing a monomer mainly composed of methyl methacrylate to an acrylic saturated crosslinked rubber is also preferably used. Among these polymethacrylic acid ester-based resins, polymethylmethacrylate is particularly preferably used.

The fluorine-based resin layer may be a single layer, but may be a plurality of layers or more. The single layer or the plurality of layers preferably contains a vinylidene fluoride resin and / or a polymethacrylic acid ester resin.

When the fluorine-based resin layer is a single layer, it is preferable that the single layer is formed of a mixture containing a polyvinylidene fluoride-based resin and a polymethacrylic acid ester-based resin. When a polymethacrylic acid ester-based resin is contained, the adhesiveness with the adhesive layer is improved. More preferably, the polymethacrylic acid ester-based resin is contained in an amount of 10 parts by mass or more, and more preferably 15 parts by mass or more, based on 100 parts by mass of the total amount of the resin components. There is no particular upper limit to the content of the polymethacrylic acid ester resin, but if it is too large, there will be a problem with weather resistance. It is contained in a proportion of 40 parts by mass or less, more preferably 40 parts by mass or less.

When the fluorine-based resin layer is a plurality of layers, a layer formed only of polyvinylidene fluoride-based resin or a ratio of polyvinylidene fluoride-based resin as the outermost layer which is the first layer of the fluorine-based resin layer. In order to ensure good adhesion to the adhesive resin layer described later as the second and subsequent layers, a layer in which the proportion of the polymethacrylic acid ester resin is gradually increased can be used. The second and subsequent layers preferably contain a high proportion of the polymethacrylic acid ester-based tree, for example, more preferably 50 parts by mass or more of the polymethacrylic acid ester-based resin with respect to 100 parts by mass of the total amount of the resin components. It is contained, more preferably 75 parts by mass or more. There is no particular upper limit to the content of the polymethacrylic acid ester-based resin, and it may be formed only of the polyvinylidene fluoride-based resin. After the second layer, even if the layer does not contain the polyvinylidene fluoride-based resin, it may be one resin layer constituting the fluororesin layer by combining with the first layer containing the polyvinylidene fluoride-based resin. Further, even when the first layer does not contain an ultraviolet blocking agent, by containing the ultraviolet blocking agent in the second and subsequent resin layers, the fluorine-based resin layer as a whole is composed of the fluorine-based resin layer containing the ultraviolet blocking agent. Can be done.

The thickness of the fluororesin layer is preferably in the range of 5 to 20 μm, more preferably 5 to 15 μm. If it is less than 5 μm, the weather resistance may be insufficient. Further, when the thickness is thicker than 20 μm, the effect of weather resistance reaches a plateau, which is not preferable from the viewpoint of cost.

As the ultraviolet blocking agent added to the fluororesin layer, for example, titanium oxide, zinc oxide, cesium oxide, iron oxide and many other types can be used. Among them, titanium oxide and zinc oxide can be preferably used. In particular, zinc oxide is excellent in terms of transparency and ultraviolet impermeableness, and when it is contained in the second layer of the fluororesin layer, it is not directly exposed to wind and rain and is not likely to elute, so that it has the effect of being used for a long period of time. It is possible to maintain. Further, when it is contained in the first layer of the fluorine-based resin layer, it is preferable to use titanium oxide which is difficult to elute.

The amount of the ultraviolet blocking agent added is preferably in the range of 1 to 5 parts by mass with respect to a total of 100 parts by mass of the resin component, for example, a polyvinylidene fluoride-based resin and a polymethacrylic acid ester-based resin. If the amount added is less than 1 part by mass, the ultraviolet shielding effect may be lowered, and if it exceeds 5 parts by mass, the transparency of the film may be lost.

It is preferable that the fluororesin layer further contains an ultraviolet absorber. The ultraviolet absorber may be any one compatible with the fluororesin, and for example, triazine-based, benzotriazole-based, oxalic acid-based, benzophenone-based, hindered amine-based and many other types can be used. Preferably, a high molecular weight type UV absorber having a molecular weight of 300 or more is preferably used in order to minimize volatilization during the production and use of the film.

The amount of the ultraviolet absorber added is preferably 2 parts by mass or less with respect to 100 parts by mass in total of the resin component, for example, the polyvinylidene fluoride-based resin and the polymethacrylic acid ester-based resin. If it exceeds 2 parts by mass, the ultraviolet shielding effect reaches a plateau, which is not preferable from the viewpoint of cost.

In addition to UV blocking agents and UV absorbers, the fluororesin layer includes stabilizers, dispersants, antioxidants, matting agents, surfactants, antistatic agents, and fluorine-based surface modifiers, if necessary. It is also possible to add various additives such as processing aids and processing aids as long as their dispersibility is not impaired.

<Adhesive resin layer>
As the resin used for the adhesive resin layer, any resin that can bond the fluorine-based resin layer and the thermoplastic resin layer may be used, and various conventionally known resins can be used. Examples thereof include acid-modified polyolefin resins including unsaturated carboxylic acid modification, chlorinated polyolefin resins, thermoplastic elastomers and the like.

The thickness of the adhesive resin layer is preferably in the range of 5 to 20 μm, more preferably 10 to 20 μm from the viewpoint of imparting sufficient adhesive force.

If necessary, various additives such as stabilizers, antioxidants, processing aids, UV blocking agents and UV absorbers are added to the adhesive resin layer to the extent that their dispersibility and transparency as a film are not impaired. It is also possible to add with.

<Thermoplastic resin layer>
A known thermoplastic resin can be used for the thermoplastic resin layer. For example, polyolefin, polystyrene, ABS resin, AS resin, polyamide, polyimide, polyester, methacrylic resin and the like can be mentioned, and among them, polyolefin can be preferably used from the viewpoint of film forming property and flexibility.

Examples of the polyolefin include polyunsaturated α-olefin homopolymers, copolymers with dissimilar monomers containing α-olefin as a main component, and conjugated diene or non-conjugated diene containing α-olefin as a main component. Examples include copolymers with compounds, such as high density, low density or linear low density polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-4-methyl-1-pentene. Examples thereof include a copolymer, an ethylene-vinyl acetate copolymer, and an ethylene-acrylic acid copolymer. Of these, low-density polyethylene having a density of 0.890 to 0.935 is preferable in terms of transparency, weather resistance, and price.

The thickness of the thermoplastic resin layer is preferably in the range of 30 to 120 μm, more preferably 50 to 120 μm, from the viewpoint of imparting sufficient strength and flexibility.

The thermoplastic resin layer may contain stabilizers, dispersants, antioxidants, matting agents, surfactants, antistatic agents, fluorosurface modifiers and processing aids, UV blocking agents and UV rays, if necessary. It is also possible to add various additives such as absorbents as long as their dispersibility and transparency as a film are not impaired.

<Drop layer>
The drop layer is coated with a colloidal layered silicate and a drop agent containing a polymer binder, a light stabilizer or an ultraviolet absorber. Since the layered silicate is colloidal and the colloid is nanometer-sized, a transparent coating film can be formed. The drop agent for forming the drop layer is preferably transparent without becoming cloudy. The particle size of the layered silicate is usually 10 to 1000 nm, preferably 10 to 100 nm.

The layered silicate is, for example, at least one selected from mica and smectite. Examples of mica include vermiculite and the like. Examples of smectite include montmorillonite, iron montmorillonite, byderite, saponite, nontronite, hectorite, stephensite and saponite. The layered silicate is preferably a synthetic layered silicate, particularly preferably a synthetic smectite.

The polymer binder is not particularly limited as long as it becomes transparent when mixed with the above-mentioned layered silicate and can stably fix the drip layer on the film, but it is not particularly limited, but it is an alcohol-soluble nylon resin or acrylic resin phenol resin. Etc. can be used, and an alcohol-soluble nylon resin is preferable. When these polymer binders are used, it is possible to form a drip layer that is hard to be peeled off even by friction due to stretching work while ensuring transparency.

The mixing ratio of the layered silicate and the polymer binder is not particularly limited as long as transparency and fixing stability are ensured, but 2 to 60 parts by mass of the layered silicate is added to 100 parts by mass of the polymer binder. It can be contained in parts, preferably 5 to 20 parts by mass. If it is less than 2 parts by mass, the contact angle of water becomes high and the drip property is low, and if it exceeds 60 parts by mass, the transparency decreases.

In order to impart weather resistance to the droplet layer, it is preferable to add a light stabilizer, and known ones can be used. As the light stabilizer, one that captures the active species at the onset of photodegradation in the resin and prevents photooxidation can be used. Specifically, one or a combination of two or more selected from hindered amine compounds, hindered piperidine compounds, and the like can be used. Above all, it is preferable to use a hindered amine compound. These light stabilizers do not easily form emulsions and have excellent coating film workability.

The film thickness of the drop layer is preferably 0.2 to 0.8 μm, more preferably 0.4 to 0.6 μm. If the film thickness of the drip layer is less than 0.2 μm, the drip performance is poor, and if it is thicker than 0.8 μm, the drip performance itself is not affected, but the productivity may be inferior.

Further, the initial value of the static contact angle of water on the surface of the drip layer according to the present invention is preferably 20 ° or less, more preferably 15 ° or less, still more preferably 13 ° or less. .. The value of the static contact angle of water after the weather resistance test is preferably 40 ° or less, more preferably 35 ° or less, still more preferably 30 ° or less, and the static contact angle is 40 °. If it exceeds, the hydrophilicity becomes insufficient and the film surface may become cloudy due to dew condensation.

<Fluorine-containing laminated film for agriculture>
The total thickness of the fluorine-containing laminated film for agriculture of the present invention is preferably in the range of 40 to 150 μm, more preferably 50 to 130 μm. If the total thickness is too thin, the desired long-term stretchability may not be ensured when used as a covering material for a green house. On the other hand, if the total thickness is too thick, the handleability at the time of extension is poor and the cost is high.

The initial value of HAZE of the fluororesin film for agriculture is preferably 10% or less, and more preferably 7% or less as the transparency. Further, the value of HAZE after the weather resistance test is preferably 15% or less, and more preferably 10% or less.

As for the transparency of the fluorine-based resin film for agriculture, the initial value of the total light transmittance is preferably 90% or more, and more preferably 91% or more. Further, the value of the total light transmittance after the weather resistance test is preferably 90% or more, more preferably 91% or more.

<Manufacturing method of fluorine-containing laminated film for agriculture>
Next, a method for producing the fluorine-containing laminated film for agriculture of the present invention will be described.

First, a laminated film in which a thermoplastic resin layer is laminated on a fluorine-based resin layer via an adhesive resin layer can be produced by a conventionally known method. For example, a method of forming each layer separately in advance and laminating, or a method of heat-bonding pressing, a method of forming a laminated film of a fluororesin layer and an adhesive resin layer in advance, and a thermoplastic resin on the surface of the adhesive resin layer. Examples thereof include a method of coating and laminating the layers, and a method of laminating and forming a film by laminating each resin layer by a coextrusion method. Of these, production by the coextrusion method is most preferable from the viewpoint of economy and production stability.

The above-mentioned drip agent is applied to the surface of the laminated film thus obtained on the thermoplastic resin layer side and dried to obtain the fluorine-containing laminated film for agriculture of the present invention having the drip layer.

A known method can be used as the method for applying the drip layer. For example, spray coating, roller coating, hand coating, rotary coating, coating by various printing methods, bar coating, die coating, spray coating and the like can be mentioned.

When forming the drop layer, applying a surface treatment on the surface of the laminated film on the thermoplastic resin layer side not only improves the coatability but also improves the adhesion of the drop layer. preferable. As a surface treatment method, various methods such as corona discharge treatment, plasma treatment, high frequency sputtering etching treatment and the like are used.

The heating temperature and time for drying are not particularly limited. The heating temperature can be, for example, 50 to 90 ° C. The time can be, for example, 1 to 60 minutes. The heating temperature and time are preferably set in consideration of the heat resistant temperature of the object to be coated.

<Agricultural covering material>
The agricultural covering material of the present invention is made by using the agricultural fluorine-containing laminated film of the present invention. Since the fluorine-containing laminated film for agriculture of the present invention has excellent weather resistance and long-term stretchability, and can maintain the drip performance in particular for a long period of time, the agricultural coating material of the present invention using the same can be used for green houses. It can be suitably used for covering materials and the like.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto. The raw materials used in the examples are as follows.

<Ingredients used>
(Fluorine resin layer)
-Vinylidene fluoride resin "Kiner K720" (manufactured by Alchema Co., Ltd.) Polyvinylidene fluoride resin "Soref 21508" (Solvey Specialty Polymers Japan Co., Ltd.) with a fluorine content of about 59% and a melting point of about 170 ° C. Polypolymer of vinylidene fluoride and hexafluoropropylene at about 130 ° C. Polymethacrylic acid ester resin "Hypet HBS000" Made by Mitsubishi Rayon Co., Ltd. (Bulch acrylate (n-BA) and butyl methacrylate (BMA) rubber Polymethacrylic acid ester-based resin containing components. MFR (230 ° C, 3.8 kg weighted) 4 to 7 (g / 10 min)): PMMA
・ Ultraviolet absorber Triazine-based ultraviolet absorber "TINUVIN 1600" Made by BASF Japan Co., Ltd. ・ Ultraviolet blocking agent Zinc oxide "FINEX-50W-LP2" Sakai Chemical Industry Co., Ltd. Titanium oxide "TTO-55 (D)" Ishihara Sangyo Co., Ltd. (Adhesive resin layer)
-Acid-modified polyolefin resin "Admer SE810" manufactured by Mitsui Chemicals, Inc. (MFR (condition: 230 ° C, 3.8 kg weighted) 7.3 (g / 10 min))
(Thermoplastic resin layer)
-Polyolefin resin Special LLDPE resin "NC566A" manufactured by Japan Polyethylene Corporation (density 0.918 g / cm ³ , MFR (condition: 230 ° C, 3.8 kg weighted) 3.8 (g / 10 min))
(Drop agent)
"Lacrain B1" manufactured by Daiwa Seikan Co., Ltd. (contains synthetic smectite as a colloidal layered silicate and methoxymethylated nylon as a polymer binder, and contains 10 parts by mass of layered silicate with respect to 100 parts by mass of the polymer binder. ) And a light stabilizer (hindered amine-based light stabilizer).)

<Example 1>
80 parts by mass of the polyvinylidene fluoride resin (PVDF) and 20 parts by mass of the polymethacrylic acid ester resin (PMMA) are blended together with 3 parts by mass of the titanium oxide in a tumbler to form a mixture, which is extruded in a φ30 mm manner. It was kneaded by a machine to obtain a compound for a fluororesin layer.
Next, the compound is used as the fluororesin layer, the acid-modified polyolefin resin is used as the adhesive resin layer, the polyolefin resin is used as the thermoplastic resin layer, and the fluororesin layer and the adhesive resin layer are each φ40 mm. The single-screw extruder of No. 1 is co-extruded by the feed block method using a single-screw extruder of φ65 mm for the thermoplastic resin layer, and is taken up by a metal cooling roll to obtain a fluororesin layer (thickness 15 μm) and an adhesive resin layer (thickness 15 μm). A laminated film having a thickness of 10 μm) and a thermoplastic resin layer (thickness of 85 μm) laminated in this order was obtained.
Next, the surface of the laminated film on the thermoplastic resin layer side was subjected to corona treatment, and then a drip agent was applied to prepare a laminated film having a drip layer having a thickness of 0.4 μm after drying.

Various evaluations of the laminated film were performed by the following methods. The results are shown in Table 1.

<Evaluation method>
(1) Optical characteristics (total light transmittance)
The laminated film was cut into 5 cm squares and measured using "NDH2000" manufactured by Nippon Denshoku Industries Co., Ltd. in accordance with JIS K 7105.

(HAZE)
The laminated film was cut into 5 cm squares and measured using "NDH2000" manufactured by Nippon Denshoku Industries Co., Ltd. in accordance with JIS K 7105.

(2) Drop performance (in-house method)
In the evaluation of the drip property, as shown in FIG. 2, the surface of the laminated film 1 to be evaluated is spread with a gradient of 15 ° with respect to the water surface in the opening of the water bath 11 in which the hot water 13 at 50 ° C. is circulated. The appearance of the film after 6 months was visually observed and evaluated as follows.
Excellent: Wet evenly like a water film without adhesion of water droplets.
Good: Water droplets adhere to an area of less than 25% of the entire film.
Possible: Water droplets are attached to an area of 25% or more and less than 75% of the entire film.
Impossible: Water droplets adhere to an area of 75% or more of the entire film.

(Static contact angle)
The static contact angle of water was measured as an index of hydrophilicity. The static contact angle of water on the surface of the laminated film 1 to be evaluated was measured with an "automatic contact angle meter DM-501" (manufactured by Kyowa Interface Science Co., Ltd.). The measurement was performed at any different 10 points on the surface to be evaluated, and the average value was calculated.

(3) Weather resistance (optical properties after UV irradiation test)
The UV irradiation test was carried out using "Dipla Metal Weather" (manufactured by Dipla Wentes Co., Ltd.) under the following conditions.
UV irradiation intensity: 132mW / cm ²
1 cycle: 12 hours (10 hours irradiation, 2 hours dark shower)
Humidity: 51%
Black panel temperature: 62 ° C
Time: 504 hours Irradiation surface: After the fluororesin layer surface test, the optical properties of the film were evaluated, and the total light transmittance and HAZE after the test were calculated.

(Static contact angle after UV irradiation test)
The static contact angle of water after the weather resistance test was measured in the same manner as described above.

<Examples 2 and 3>
A laminated film having a droplet layer was prepared and evaluated in the same manner as in Example 1 except that the composition of the fluororesin layer was changed as shown in Table 1. The results are shown in Table 1.

<Example 4>
100 parts by mass of PMMA was blended with 2 parts by mass of zinc oxide in a tumbler to form a mixture, which was kneaded with a twin-screw extruder having a diameter of 30 mm to obtain a compound for a second fluorine-based resin layer.
Next, 100 parts by mass of PVDF as the first fluororesin layer, the compound as the second fluororesin layer, the acid-modified polyolefin resin as the adhesive resin layer, and the polyolefin-based as the thermoplastic resin layer. Using a resin, a single-screw extruder having a diameter of 40 mm was used for the first fluororesin layer, the second fluororesin layer and the adhesive resin layer, and a single-screw extruder having a diameter of 65 mm was used for the thermoplastic resin layer. The first fluororesin layer (thickness 5 μm), the second fluororesin layer (thickness 10 μm), the adhesive resin layer (thickness 10 μm), and the thermoplastic resin layer are co-extruded by the feed block method and taken up by a metal cooling roll. A laminated film laminated in the order of (thickness 75 μm) was obtained.
Next, in the same manner as in Example 1, a laminated film having a drip layer having a thickness of 0.4 μm after drying was prepared and evaluated on the surface of the laminated film on the thermoplastic resin layer side. The results are shown in Table 1.

<Example 5>
20 parts by mass of PVDF and 80 parts by mass of PMMA are blended together with 2 parts by mass of zinc oxide in a tumbler to form a mixture, which is kneaded by a twin-screw extruder having a diameter of 30 mm to obtain a compound for a second fluororesin layer. Obtained. A laminated film having a droplet layer was prepared and evaluated in the same manner as in Example 4 except that the compound was changed to the above-mentioned compound as the second fluorine-based resin layer. The results are shown in Table 1.

<Example 6>
20 parts by mass of PVDF and 80 parts by mass of PMMA are blended with 1 part by mass of the triazine-based ultraviolet absorber and 1 part by mass of zinc oxide in a tumbler to form a mixture, which is kneaded by a twin-screw extruder having a diameter of 30 mm to obtain a second mixture. A compound for a fluororesin layer was obtained. A laminated film having a droplet layer was prepared and evaluated in the same manner as in Example 4 except that the compound was changed to the above-mentioned compound as the second fluorine-based resin layer. The results are shown in Table 1.

<Examples 7 to 12>
A laminated film having a droplet layer was prepared and evaluated in the same manner as in Example 4 except that the composition of the fluororesin layer was changed as shown in Table 1. The results are shown in Table 1.

<Examples 13 and 14>
A laminated film having a drop layer was prepared and evaluated in the same manner as in Example 7 except that the film thickness of the drop layer was changed as shown in Table 1. The results are shown in Table 1.

<Examples 15 and 16>
A laminated film having a drop layer was prepared and evaluated in the same manner as in Example 7 except that the film thicknesses of the drops were changed to 0.15 μm and 1 μm, respectively. The results are shown in Table 1.

<Comparative Example 1>
A laminated film was prepared and evaluated in the same manner as in Example 4 except that a laminated film having a film thickness of 100 μm was used without providing a drop layer. The results are shown in Table 1.

<Comparative Example 2>
100 parts by mass of PMMA was blended with 2 parts by mass of zinc oxide in a tumbler to form a mixture, which was kneaded with a twin-screw extruder having a diameter of 30 mm to obtain a compound for a fluororesin layer.
A laminated film having a droplet layer was prepared and evaluated in the same manner as in Example 1 except that the compound was used as the fluororesin layer. The results are shown in Table 1.

<Comparative Example 3>
A film having a drip layer was produced in the same manner as in Example 1 except that a single-layer film of a thermoplastic resin having a thickness of 100 μm was used without providing a fluorine-based resin layer and an adhesive resin layer. The results are shown in Table 1.

<Comparative Example 4>
A film having a drop layer was produced in the same manner as in Example 1 except that no ultraviolet blocking agent was added. The results are shown in Table 1.

1: Fluorine-containing laminated film for agriculture 3: Fluorine resin layer 5: Adhesive resin layer 7: Thermoplastic resin layer 9: Droplet layer 11: Water bath 13: Hot water

Claims (6)

A thermoplastic resin layer is arranged via an adhesive resin layer on one surface of a fluororesin layer containing an ultraviolet blocking agent, and a layered silicate and a polymer are arranged on the surface of the thermoplastic resin layer facing the adhesive resin layer. Equipped with a drip layer containing a binder and a light stabilizer,
The drop layer contains 2 to 20 parts by mass of the layered silicate with respect to 100 parts by mass of the polymer binder.
The fluorine-based resin layer is a multi-layer having two or more layers.
The outermost layer of the two or more layers contains a vinylidene fluoride resin.
Agricultural fluorine-containing laminated film (excluding agricultural fluorine-containing laminated film having a layer having a vinylidene fluoride resin content of 95 parts by mass or less as the outermost layer with respect to 100 parts by mass of the total amount of resin components) .. The agricultural fluorine-containing laminated film according to claim 1, wherein the fluorine-based resin layer further contains an ultraviolet absorber. The fluorine-containing laminated film for agriculture according to claim 1 or 2, wherein the film thickness of the droplet layer is 0.2 to 0.8 μm. The agricultural fluorine-containing laminated film according to any one of claims 1 to 3, wherein the value of the static contact angle of water on the surface of the droplet layer after the weather resistance test is 40 ° or less. The agricultural fluorine-containing laminated film according to any one of claims 1 to 4, wherein the two or more layers include the vinylidene fluoride resin and / or the polymethacrylic acid ester resin. An agricultural coating material using the fluorine-containing laminated film for agriculture according to any one of claims 1 to 5.

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