JP6952364B2 - Agricultural film - Google Patents

Description

The present invention relates to an agricultural film, and more particularly to an agricultural film capable of suitably realizing a highly shadowless environment.

The diffused film not only diffuses the sunlight transmitted through the film to make it soft, but also diffuses the light to deliver the light to a place where the sunlight normally does not reach as a shadow. (Patent Document 1).

Japanese Patent No. 3763380

With the conventional diffused film, even if the sun's rays are diffused, there may still be a shadowed portion, and there is room for improvement in providing a so-called shadowless environment.

Therefore, an object of the present invention is to provide an agricultural film capable of suitably realizing a highly shadowless environment.

Further, other problems of the present invention will be clarified by the following description.

The above problems are solved by the following inventions.

(Claim 1)
A diffuser dispersion film layer is laminated on one side of the transparent resin film layer,
The diffuser dispersion film layer is a large diffuser that converts light incident through the transparent resin film layer into first scattered light, and the first scattered light is further scattered in multiple directions. At least a small diffuser having a diameter smaller than the particle size of the large diffuser, which produces a second scattered light, is dispersed and blended.
An agricultural film characterized by emitting scattered light in multiple directions from the surface or inner surface of the diffuser dispersion film layer to form a highly shadowless environment in a house or a tunnel.
(Claim 2)
The agricultural film according to claim 1, wherein the diffuser dispersion film layer is used by spreading it toward an agricultural product cultivated in the house or a tunnel.
(Claim 3)
A diffuser dispersion film layer is laminated on one side of the transparent resin film layer,
The diffuser dispersion film layer imparts anti-fog property and is formed.
A large convex surface formed by the large light diffuser that generates the first scattered light is formed on the surface of the diffuser dispersion film layer, and the first scattered light is formed around the large light diffuser that forms the large convex surface. A small convex surface is formed by a small light diffuser having a diameter smaller than the particle size of the large light diffuser, which further diffuses light to generate a second scattered light.
Agricultural film characterized by being used when heat insulation is required.

According to the present invention, it is possible to obtain an effect of providing an agricultural film capable of suitably realizing a highly shadowless environment.

The figure which conceptually explains the layer structure of the agricultural film of this invention The figure which conceptually explains the diffused light by the agricultural film of this invention The figure explaining the test method of an Example The figure which shows the result of an Example

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

FIG. 1 is a diagram conceptually explaining the layer structure of the agricultural film of the present invention.
The agricultural film 1 is composed of a transparent resin film layer 2 and a diffuser dispersion film layer 3.

As the transparent resin used for the transparent resin film layer 2 and the diffuser dispersion film layer 3, polyolefins such as ethylene-based polymers and propylene-based polymers, vinyl chloride, and the like can be used. Among them, low-density polyethylene, linear low-density polyethylene, and ethylene-vinyl acetate copolymer are preferable from the viewpoint of antifouling property and durability.

In the present invention, transparent, opaque or translucent means whether or not sunlight is not scattered and travels straight through the film, but does not mean whether or not sunlight is transmitted.

The resin forming the transparent resin film layer 2 and the resin forming the diffuser dispersion film layer 3 may be different resins, but in order to obtain adhesiveness between the two layers, resins having the same chemical composition are used. It is also preferable.

The large diffuser 30 and the small diffuser 31 are dispersed in the diffuser dispersion film layer 3. The large diffuser 30 has one particle shown in the figure, and the small diffuser 31 is dispersed around or in the vicinity of the large diffuser 30.

The large diffuser 30 has a particle size of 1 μm to 10 μm, preferably 2 μm to 4 μm, and a blending amount of the diffuser dispersion film layer 3 with respect to the total weight is 3 wt% to 15 wt%, preferably 5 wt% to 10 wt%. ..

The small diffusing agent 31 has a particle size of 0.1 μm to 0.9 μm, preferably 0.2 μm to 0.6 μm, and the blending amount of the small diffusing agent 31 with respect to the total weight of the diffusing agent dispersion film layer 3 is 0.3 wt% to 2 wt%. , Preferably 0.5 wt% to 1.2 wt%.

The blending amount of the small diffuser 31 is smaller than that of the large diffuser 30 in terms of weight. However, the volume of the small diffuser 31 (proportional to the cube of the particle size) is significantly smaller than that of the large diffuser 30, and since there is no large difference in the specific gravity at this time, the blending quantity of the small diffuser 31 with respect to the large diffuser 30. The ratio will be significantly higher.

In the present invention, the compounding quantity ratio of the small diffuser 31 to the large diffuser 30 is preferably 60 to 100 times. As a result, a large convex surface derived from the large diffuser 30 is formed on the surface of the diffuser dispersion film layer 3, and a small convex surface due to the small diffuser 31 is further formed on the surface of the large convex surface.

Next, with reference to FIG. 2, the light scattering by the agricultural film 1 will be conceptually described. FIG. 2 shows an enlarged area A surrounded by a dotted line in FIG.

In FIG. 2, the light transmitted through the transparent resin film layer 2 (not shown) and incident on the diffuser dispersion film layer 3 is first converted into the first scattered light by the large scattering agent 30, and then the first scattered light. Generates a second scattered light that is further scattered in multiple directions by the small diffuser 31. As a result, scattered light is emitted in multiple directions from the surface (inner surface) of the light diffuser dispersion film layer 3, and a highly shadowless environment is formed.

Examples of the large diffuser 30 include alkaline orthoclase, silicon oxide, and various natural or synthetic silicates. Among them, nepheline or nepheline syenite (nepheline syenite) is preferably used. can. As a commercially available product, "MINEX 7" manufactured by Unimin Co., Ltd. can be used.

Hydrotalcites are used as the small diffuser 31. Hydrotalcites are compounds represented by the formula M ²⁺ _1-x Al ³⁺ _x (OH ⁻ ) ₂ (A ₁ ^{n −} ) _{x / n} · mH _{2 O.} In the above formula, M ²⁺ represents a divalent metal ion selected from the group consisting of Mg ²⁺ , Ca ²⁺ and Zn ²⁺ _{, A 1} ⁿ⁻ is an n-valent anion, and x is 0 <x <0. A number in the range of 5, m is a number in the range of 0 ≦ m ≦ 2, and n is a number in the range of 1 ≦ n ≦ 3. As the hydrotalcites, for example, DHT (manufactured by Kyowa Chemical Industry Co., Ltd.) and the like can be preferably used.

In the tomato cultivation example using such an agricultural film, withered leaves were rarely confirmed. The volume of the dead leaves was less than 10% of the volume of the grown leaves. In addition, no burnt tomatoes were found even after the end of the rainy season.

Furthermore, it was confirmed that the height of the entire stock inside the house was almost constant. This is also an effect of the shadowless environment. When a shadow is formed, the leaves that exist there are withered, and the stem grows in an attempt to attach the leaves where photosynthesis is possible. This will result in taller strains.

In the film of the present invention, since there was no such high strain, the same growth was achieved in all the strains. As a result of the above, vegetative growth is suppressed and energy is spent on reproductive growth, so that the yield of tomatoes can be increased.

The film thickness of the transparent resin film layer 2 can be arbitrarily set, but is 5 μm or more, preferably 10 μm or more, and generally 10 to 150 μm. When the film thickness is thinner than 5 μm, it becomes difficult to smooth the film surface and the transparency is lowered. The film thickness of the diffuser dispersion film layer 3 can be set arbitrarily, but is generally 5 to 200 μm, preferably 10 to 100 μm.

That is, the total film thickness of the agricultural film 1 is preferably 15 to 300 μm, more preferably 50 to 200 μm.

The method of laminating the transparent resin film layer 2 and the diffuser dispersion film layer 3 is not particularly limited. For example, the diffuser dispersion film layer 3 may be formed in advance and the transparent resin film layer 2 may be laminated on the transparent resin film layer 2 by extrusion laminating. May be laminated by extrusion laminating. Further, by inflation molding, the resin compositions of both layers can be extruded at the same time and laminated in or immediately after being extruded from the die.

The diffuser dispersion film layer 3 is preferably oriented toward the crop side (inside). By using the diffuser dispersion film layer 3 inside, the transparent resin film layer 2 becomes the outer layer of the film, so that the outer surface of the film becomes a smooth surface and the diffuser dispersion film layer 3 becomes the inner layer of the film. As a result, a pear-ground surface having minute irregularities is formed on the inner surface of the film, and shadowlessness can be suitably realized.

Further, the surface of the diffuser dispersion film layer 3 may be provided with anti-fog property. As a method for imparting anti-fog property, a method of kneading a compound having a hydrophilic group such as a surfactant into the diffuser dispersion film layer 3 can be adopted, and the surface of the diffuser dispersion film layer 3 is protected. A fogging agent can also be applied.

A nonionic, anionic or cationic surfactant can be used as the antifog-imparting agent when kneaded into the diffuser dispersion film layer 3. Examples of these compounds include polyoxyalkylene ethers, partial esters of polyhydric alcohols, partial esters of alkylene oxide adducts of polyhydric alcohols, higher alcohol sulfate alkali metal salts, alkylaryl sulfonates, quaternary ammonium, and fatty acid amine derivatives. Can be mentioned. Of these, an ester of a fatty acid having 14 to 22 carbon atoms and a polyhydric alcohol such as sorbitol, sorbitol, glycerin, or propylene glycol, or a nonionic surfactant containing an alkylene oxide adduct thereof as a main component is preferable.

The anti-fog agent applied to the diffuser dispersion film layer 3 to impart anti-fog properties is preferably one containing inorganic fine particles and a surfactant, and the inorganic fine particles are inorganic particles having a particle size of about 5 to 100 nm. Hydrophilic colloidal substances can be used. Specifically, colloidal silica, colloidal alumina, colloidal iron hydroxide, tin hydroxide, titanium oxide, barium sulfate, lithium silicate and the like can be used.

The anti-fog agent may be applied before being applied to the tunnel aggregate or the skeleton for the cultivation house, or may be applied after being applied to these at a necessary time.

The agricultural film 1 thus obtained becomes opaque or translucent in a dry state, and becomes transparent when the three surfaces of the diffuser dispersion film layer are wet.

In the agricultural film 1 of the present invention, the transparent resin film layer 2 may be a single layer or a laminated film layer. Therefore, the agricultural film 1 of the present invention may have a structure of three or more layers.

Then, various functions such as various ultraviolet absorbers, light stabilizers (improved weather resistance), heat insulating agents, infrared absorbers, etc. may be appropriately added to each layer as long as the effects of the present invention are not impaired. can.

When the agricultural film 1 of the present invention is used, it is used and constructed in the same manner as before except that the three light diffuser dispersion film layers are stretched so as to be the inner surface of the film (inside of a tunnel, a house, etc.). It is laid on the skeleton of a tunnel or house, and crops are cultivated inside it.

When cultivating using the agricultural film 1, when heat insulation is required such as in winter, the cultivation is carried out with the house or tunnel closed. When cultivating with the house or tunnel closed, the temperature can be kept warm and the cultivation temperature can be raised, and the internal humidity rises, and the moisture adheres to the three surfaces of the diffuser dispersion film layer of the agricultural film 1. The attached water becomes a water film on the surface of the diffuser dispersion film layer 3 due to the action of the anti-fog agent. As a result, the agricultural film 1 becomes transparent and the crop is exposed to direct sunlight.

On the other hand, after April to May in the spring, especially in the summer when the temperature is high and the sunlight is strong, the agricultural film 1 is partially pulled up and ventilated for cultivation. When the inside of the tunnel or the house is ventilated, the inside is dried and the water film on the inner surface of the agricultural film 1 disappears. As a result, the agricultural film 1 becomes opaque or translucent, and the direct sunlight is dispersed to become soft light, which is applied to the crop. Therefore, it is possible to prevent high temperature damage such as burning in the crop, and it can be used for cultivation of many crops such as vegetables, fruit crops and flowers.

Examples of the present invention will be described below, but the present invention is not limited to such examples.

1. 1. Production of Film An agricultural film (laminated film) having a transparent resin film layer having each of the following configurations and a diffuser dispersion film layer was produced by an inflation molding method.
The transparent resin film layer and the diffuser dispersion film layer were single layers, respectively.

<Transparent resin film layer>
It was formed from 100 parts by weight of an ethylene-vinyl acetate copolymer (MI: 0.5, vinyl acetate content 15%). The thickness was 100 μm.

<Diffuse agent dispersion film layer>
With respect to 100 parts by weight of an ethylene-vinyl acetate copolymer (MI: 0.5, vinyl acetate content 15%) which is a transparent resin, 7 parts by weight of the following large diffuser and 0.8 parts by weight of the following small diffuser are added. Blended and mixed. The thickness of the diffuser dispersion film layer is 30 μm.
Large diffuser: Nepheline syenite (Nepheline syenite) (Unimin's "MINEX 7"), grain size 3.5 μm
Small diffuser: Hydrotalcite ("DHT-4A" manufactured by Kyowa Chemical Industry Co., Ltd.), particle size 0.4 μm

2. Cultivation test As shown in Fig. 3, the obtained film 1 is spread in a house (height 3.6 m) provided at Mikado Chemical Co., Ltd. Houda Experimental Farm, and is 50 cm below (P1) and 1 m below (P1) from the film 1. The amount of diffused light reaching each position of P2), 2 m below (P3), 3 m below (P4), the ground inside the house (P5), and the ground outside the house (P6) was measured as the average illuminance for each time zone. The results are shown in FIG.

<Evaluation>
First, as shown by the dotted line in FIG. 4A, in the transparent film (comparative) containing no large diffuser and small diffuser, the illuminance usually decreases from the film toward the ground inside the house.

On the other hand, in the film of the present invention, as shown in the bar graph of FIG. 4 (a), in the time zone from 10:00 to 11:00, the transparent film (1 m below the film to the ground inside the house). It can be seen that a larger illuminance than (comparison) is measured.

In particular, it can be seen that the illuminance is higher in the region from 1 m below to 2 m below the film than directly below the film (50 cm below the film). From these facts, it can be seen that the film of the present invention can suitably realize a highly shadowless environment.

Further, as shown in the bar graph of FIG. 4B, it can be seen that the illuminance in the region from 1 m to 3 m below the film is slightly reduced in the time zone from 12:00 to 13:00. Therefore, according to the film of the present invention, in addition to the above-mentioned effect of shadowlessness, an effect of preventing the plants in the house from being irradiated with excessive light during the time when the elevation angle of the sun is large can be obtained.

Furthermore, as shown in the bar graph of FIG. 4C, in the time zone from 14:00 to 13:00, the illuminance is in the region from 1 m below to 3 m below the film rather than directly under the film (50 cm below the film). It can be seen that a high degree of shadowless environment can be suitably realized.

1: Agricultural film 2: Transparent resin film layer 3: Diffusing agent dispersion film layer 30: Large diffusing agent 31: Small diffusing agent

Claims (3)

A diffuser dispersion film layer is laminated on one side of the transparent resin film layer,
The diffuser dispersion film layer is a large diffuser that converts light incident through the transparent resin film layer into first scattered light, and the first scattered light is further scattered in multiple directions. At least a small diffuser having a diameter smaller than the particle size of the large diffuser, which produces a second scattered light, is dispersed and blended.
An agricultural film characterized by emitting scattered light in multiple directions from the surface or inner surface of the diffuser dispersion film layer to form a highly shadowless environment in a house or a tunnel. The agricultural film according to claim 1, wherein the diffuser dispersion film layer is used by spreading it toward an agricultural product cultivated in the house or a tunnel. A diffuser dispersion film layer is laminated on one side of the transparent resin film layer,
The diffuser dispersion film layer imparts anti-fog property and is formed.
A large convex surface formed by the large light diffuser that generates the first scattered light is formed on the surface of the diffuser dispersion film layer, and the first scattered light is formed around the large light diffuser that forms the large convex surface. A small convex surface is formed by a small light diffuser having a diameter smaller than the particle size of the large light diffuser, which further diffuses light to generate a second scattered light.
Agricultural film characterized by being used when heat insulation is required.

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