JP2001231375A - Method for preventing deterioration of agricultural curtain material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inexpensively realize a method for further improving the durability of agricultural curtain materials without disupting the suitable environment for cultivated crops in a greenhouse. SOLUTION: In an agricultural greenhouse 1 formed out of a material 2 for greenhouse raising which has an average ultraviolet-ray (wavelength of <=350 nm) transmissivity >=50% and retaining an agricultural curtain material 3 made of a woven or nonwoven fabric formed out of a synthetic resin raw material in a stored condition inside the top part of the ceiling of the greenhouse 1 when the material 3 is out of use, the greenhouse 1 features that a transparent material 5 characterized by an average visible-light (wavelength of 400-700 nm) transmissivity of 85-95%, an average ultraviolet-ray (wavelength of <=350 nm) transmissivity of <=50% and a haze of 1-50 intervenes between both materials 2 and 3 in such a way that sunlight in which quantities of ultraviolet radiation and direct solar radiation are adjusted with the material 5 irradiates the material 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preventing deterioration of agricultural curtain materials, and more particularly to a method for preventing agricultural curtain materials from deteriorating at a low cost to realize a method for further improving the durability of agricultural curtain materials. .

[0002]

2. Description of the Related Art Conventionally, in house cultivation in which various crops are cultivated in an agricultural house, curtains are used in summer to prevent the house temperature from excessively rising due to strong sunlight during the day and in winter to maintain the house temperature. It has been practiced to spread materials appropriately to the top of the house, improve the environment inside the house, and grow healthy crops.

As such a curtain material, an agricultural curtain material made of a woven or non-woven fabric formed by using a synthetic resin material such as polyethylene, polypropylene, polyethylene terephthalate, or polyester is known. It has been accepted by agricultural producers because it has excellent functions.

[0004]

Agricultural curtain materials are stretched so as to cover the top of the house when in use, and are folded or rolled up when not in use, depending on the size of the house. Agricultural curtain materials stored and held inside the top of the house ceiling when not in use are stored and held inside the bottom of the ceiling. It has been found that there is a case where deterioration of strength, breakage and the like is caused earlier than in the case of agricultural curtain materials, and the service life is short.

The inventor of the present invention has made intensive studies on the problem of deterioration of agricultural curtain materials, and has obtained the following knowledge.

[0006] In order to irradiate cultivated crops with sunlight as close to nature as possible, house cultivation materials constituting an agricultural house include ultraviolet rays (wavelength of 350 nm or less) of sunlight.
Some of them function to transmit light (average transmittance of 50% or more). The reason for transmitting the ultraviolet light of sunlight in this way is that the ultraviolet light not only enhances the coloration of the eggplant fruit and flowers and enhances the commercial value, but also enhances the activity of the hybrid honeybee in strawberry and melon cultivation. Although the existence is important, it was found that the deterioration of the agricultural curtain material was concentrated in the agricultural house constructed using the house cultivating material having the function of transmitting ultraviolet rays.

Therefore, it is considered that the cause of the deterioration of the agricultural curtain material is due to the ultraviolet rays of the sunlight, and compared with the agricultural curtain material stored and held inside the ceiling hem of the house when not in use. Deterioration of agricultural curtain materials stored and held inside the ceiling top is always caused by direct sunlight during the day, even when not in use, because the storage and holding position is at the top of the house, even when not in use. It is considered that the amount of irradiation of ultraviolet rays during the day is large, which causes early deterioration.

In order to prevent such deterioration due to ultraviolet rays, it is generally considered that a shielding plate or the like for blocking sunlight is provided above the agricultural curtain material. It cannot be adopted at all because it will generate.

For this reason, the present inventor has tried to apply an ultraviolet absorber to agricultural curtain materials or to mix an ultraviolet deterioration preventive agent into a resin material, but the cost has been significantly increased, so that practical use has been made. However, surprisingly, the improvement of the deterioration improvement effect was not so much seen.

Therefore, an object of the present invention is to realize a method for further improving the durability of agricultural curtain materials at a low cost without destroying a suitable environment for cultivated crops in a house.

[0011]

Means for Solving the Problems As a result of intensive studies conducted by the present inventor to solve such a problem, deterioration of agricultural curtain materials is not caused only by ultraviolet rays of sunlight but is caused by agricultural curtain materials. The present invention has been achieved by ascertaining that the direct light of sunlight irradiating the surface also affects the present invention. The method for preventing deterioration of agricultural curtain materials according to the present invention uses ultraviolet rays (wavelength of 350 nm or less).
An agricultural curtain material made of a woven or non-woven fabric made of a synthetic resin material is placed on the inside of the ceiling top of an agricultural house made of a house cultivation material having an average transmittance of 50% or more. In an agricultural house housed and held at the time of use, an average transmittance of visible light (wavelength: 400 nm to 700 nm) of 85 to 95% and ultraviolet light (wavelength of 350 nm or less) between the house cultivation material and the agricultural curtain material. ) Is not more than 50% and HAZE
, Wherein a transparent material having a characteristic of 1 to 50 is interposed, and the amount of ultraviolet light and the amount of direct light are adjusted by the transparent material to irradiate the agricultural curtain material.

As a preferred mode of disposing the transparent material,
The transparent material is disposed above the stored agricultural curtain material in any of a triangular shape, a curved shape, and a horizontal shape when viewed from the longitudinal direction of the agricultural house.

Further, a transparent material made of a transparent film is rolled and held on the lower side of the agricultural curtain material in the storage and holding portion of the agricultural curtain material, and the transparent material is stored with respect to the stored agricultural curtain material. It is also preferable to cover the agricultural curtain material so as to cover the agricultural curtain material.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The method for preventing deterioration of agricultural curtain materials according to the present invention is directed to an agricultural house made of a house cultivation material having an average transmittance of ultraviolet rays (wavelength of 350 nm or less) of 50% or more. On the inside of the ceiling top, in an agricultural house that stores and holds agricultural curtain materials made of a woven or nonwoven fabric formed using a synthetic resin material when not in use, the house cultivating materials and agricultural curtain materials The average transmittance of visible light (wavelength 400 nm to 700 nm) is 85 to 95%, and ultraviolet light (wavelength 350 nm or less)
Has an average transmittance of 50% or less and a HAZE of 1
A transparent material having a characteristic of ５０50 is interposed, and the amount of ultraviolet light and the amount of direct light are adjusted by the transparent material to irradiate the agricultural curtain material.

The agricultural greenhouse to which the present invention is applied is one in which the average transmittance of ultraviolet (wavelength: 350 nm or less) of greenhouse cultivation material is 50% or more. An agricultural house formed using such materials for cultivating a house can cultivate a cultivated crop with sunlight in a state close to nature and grow a good-quality crop. In general, a transparent resin film, for example, a transparent polyolefin resin film, is used as the material for house cultivation.

Agricultural curtain materials are good for cultivated crops in the house by spreading them over the top of the house when the sunshine is strong in the summer or when it is necessary to keep warm in the winter, or when necessary. When not in use, inside the top of the ceiling of the house,
Wrapped around the core extending along the length of the house,
Alternatively, it is folded and held and held toward the ceiling top side of the house.

Examples of such agricultural curtain materials include agricultural curtain materials formed of a woven or nonwoven fabric formed using a synthetic resin material such as polyethylene, polypropylene, or polyester. For example, agricultural curtain materials made of polyester woven fabric are disclosed in Japanese Patent Application No. 11-139.
840 can be referred to.

In the present invention, the transparent material is interposed between the house cultivation material and the agricultural curtain material, and adjusts ultraviolet rays and direct light of sunlight radiated on the agricultural curtain material. It prevents deterioration of agricultural curtain materials.

In order to achieve this object, the transparent material of the present invention has an average transmittance of visible light (wavelength: 400 nm to 700 nm) of 85 to 95%. If it is less than 85%, the transparent material itself forms a shadow, which is not preferable. This is because the transparent material may function as a light-shielding material for sunlight, which may make it impossible to grow healthy cultivated crops. The upper limit is set to 95% because it is almost the maximum value of the transmittance of the plastic. 88% or more is more preferable.

The transparent material has an average transmittance of 50% or less for ultraviolet rays (wavelength of 350 nm or less). If it exceeds 50%, the influence of the deterioration of the agricultural curtain material due to ultraviolet rays becomes large. It is preferably at most 20%, more preferably at most 10%.

Further, the transparent material HAZE (measuring method: JI
SK-7105) is in the range of 1 to 50. This H
The value of AZE means scattering of light. If the transparent material is within the scope of the present invention, light transmitted through the transparent material is scattered, and the direct light to the curtain material for agricultural use is reduced. The temperature of the surface of the curtain material or its surroundings can be prevented from rising. That is, in the present invention, in addition to the decrease in the amount of transmitted ultraviolet light, the amount of direct light is also reduced to suppress a rise in temperature, and to prevent deterioration of agricultural curtain materials due to the rise in temperature.

When HAZE is less than 1, the light scattering effect is small, and it is not possible to sufficiently reduce the direct light reaching the agricultural curtain material. On the other hand, if it exceeds 50, the surface scattering of incident light becomes too large, the total transmittance of visible light also decreases, and the transparent material itself forms a shadow, which is not preferable. A more preferred value of HAZE is in the range of 5-30.

The transparent material used in the present invention may be in the form of a film or a plate. The material of the transparent material is not particularly limited as long as the material satisfies the above conditions. In the case of a film, a thermoplastic resin can be used, and in the case of a plate, glass or a thermosetting resin is used. be able to. Above all, a transparent film made of a polyolefin resin is preferable from the viewpoint of workability and cost.

The polyolefin resin preferably used in the case of a transparent film includes low-density polyethylene,
Α-olefin homopolymers such as linear low-density polyethylene and copolymers with different monomers containing α-olefins as main components, such as ethylene-propylene copolymer and ethylene-butene 1 copolymer , Ethylene-4-methyl-1
-Ethylene-α-olefin copolymers such as pentene copolymer, ethylene-hexene copolymer, ethylene-octene copolymer, ethylene-decene copolymer, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer Examples thereof include a polymer, an ethylene-methyl methacrylate copolymer, an ethylene-vinyl acetate-methyl methacrylate copolymer, and an ionomer copolymer. These resins can be used alone or in a blend. In addition, a soft film such as polyvinyl chloride can be used.

Among the above-mentioned polyolefin resins, particularly preferred are α-olefin homopolymers, α-olefin copolymers, and vinyl acetate vinyl acetate copolymers.

The above resin has an average transmittance of ultraviolet rays of 5
An ultraviolet absorber is added so as to be 0% or less. Benzophenone, benzotriazole, oxalic acid anilide, titanium dioxide, zinc oxide, cerium oxide and the like can be used as the ultraviolet absorber. Among them, benzophenone and benzotriazole are preferred.

Further, in order to adjust the HAZE in the range of 1 to 50, it is preferable that the transparent film contains an inorganic filler or the film surface is roughened.
The treatment may be on only one side of the film.

Examples of the inorganic filler include calcium carbonate, talc, silica, alumina, zeolite and the like.

As a method of roughening the film surface,
There are embossing, sand blasting, flame treatment and the like.

In addition, various additives used for agricultural resin films, such as a weather stabilizer, an antioxidant, a lubricant, an antiblocking agent, and a dripless agent, can be added as needed.

As a method for producing a film, a known molding method such as inflation extrusion molding or T-die extrusion molding can be used as appropriate.

In the case where a plate made of a thermosetting resin is used as the transparent material, a transparent material which satisfies the above conditions can be similarly obtained by adding an ultraviolet absorber, adding an inorganic filler or roughening the surface to the resin. Can be obtained.

When a transparent glass is used as the transparent material, the above conditions are adjusted by adding an inorganic filler or applying a paint containing an ultraviolet absorber to both or one surface of the glass having a roughened surface. A satisfactory transparent material can be obtained.

Next, a specific embodiment in which such a transparent material is stretched will be described with reference to the drawings, in the case where a transparent film made of a thermoplastic resin is used as the transparent material.

FIG. 1 shows a cross section of the structure of an agricultural house viewed from a direction along the longitudinal direction. In the figure, 1 is an agricultural house, 2 is a material for cultivating a house, 3 is a curtain material for agricultural use, 4 is a cultivated crop and 5 is a transparent material.

In the illustrated example, the agricultural curtain material 3 has one end fixed to a beam 7 extending along the longitudinal direction of the house 1 and the other end wound around a core 3a. The lower surface is supported by a large number of wires 6 which extend toward the left and right sides in the longitudinal direction of the house 1 while being inclined downward from the center of the top, and are provided at appropriate intervals along the longitudinal direction of the house 1. , The wire 6
The agricultural curtain material 3 is stretched out from the core 3a while being extended, and covers the top of the house 1. When the agricultural curtain material 3 is not used, the stretched agricultural curtain material 3 is beamed. , Is wound along the wire 6 while being wound around the core 3a, and is housed inside the ceiling top as shown in the figure.

The transparent member 5 interposed between the house cultivation material 2 and the agricultural curtain material 3 is stretched along the longitudinal direction of the house 1 above the housed agricultural curtain material 3. Seen from the direction, a triangular shape, a curved shape, and a horizontal shape are given.

When the transparent material is stretched in a triangular shape, FIG.
As shown in (a), along the longitudinal direction of the house, beams a
Can be stretched in a triangular shape by arranging three of them so as to form the vertices of a triangle and supporting the transparent material 5. In order to fix the transparent member 5 to the beam a, an appropriate fixture such as a packer may be used.

When the transparent material is stretched in a curved shape, FIG.
As shown in (b), a curved state can be created by appropriately increasing the number of beams a from a triangular shape. Further, curved aggregates (not shown) may be arranged at appropriate intervals along the longitudinal direction of the house, and a transparent material may be stretched over each aggregate.

When the transparent material is stretched horizontally, FIG.
As shown in (c), the transparent member 5 can be stretched by bridging the transparent material 5 between two beams a, a arranged along the longitudinal direction of the house.

To ensure that the transparent material 5 is stretched above the agricultural curtain material 3, it is desirable that the number of the beams a is large, but as the number increases, the beams form a shadow on the cultivated crop 4. In addition, since the stretching work becomes complicated and costly, it is most preferable to stretch the transparent member 5 in a triangular shape by three beams a as shown in FIG. This is because, by covering the transparent material 5 from above like an umbrella, the stored and held agricultural curtain material 3 can be reliably covered, and the influence on the cultivated crop 4 can be reduced.

In order to stretch the transparent member 5, a wire or a single wire can be used instead of the beam a described above.

When the transparent material 5 is interposed above the agricultural curtain material 3 as described above, it is preferable to dispose the transparent material 5 as close as possible to the stored and held agricultural curtain material 3. This is to prevent light having a reduced amount of transmitted ultraviolet light from being transmitted through the transparent material 5 from being irradiated to the cultivated crop 4 as much as possible, and to irradiate only the agricultural curtain material 3 immediately below. Specifically, using the example of FIG. 2A, the distance L1 between the lowermost end of the transparent material 5 and the uppermost end of the agricultural curtain material 3 in a stored and held state is 30.
cm.

The transparent material 5 is an agricultural curtain material 3.
In order to prevent deterioration over the whole, the agricultural curtain material 3 is preferably stretched wider than the storage width of the agricultural curtain material 3 stored and held. Specifically, similarly, FIG. To illustrate using an example, the distance L2 between the outermost end of the transparent material 5 and the outermost end of the stored and held agricultural curtain material 3 is preferably 1 cm to 100 cm, more preferably 1 cm to 100 cm.
50 cm, more preferably 5-10 cm,
It is preferable that the transparent material 5 extends on both left and right sides in the longitudinal direction of the agricultural curtain material 3. If it exceeds 100 cm, the ratio of light transmitted through the transparent material 5 increases, and the total irradiation amount on the cultivated crop 4 decreases, which is not preferable.

In the above-described embodiment, an example in which the agricultural curtain material 3 is wound around the core 3a extending along the longitudinal direction of the house 1 inside the ceiling of the house 1 has been described. Even in the case where the curtain material 3 is folded and stored toward the top of the ceiling of the house 1 and is stored and held, the transparent material 5 can be similarly stretched to prevent its deterioration.

In the above embodiment, the case where the two agricultural curtain materials 3 wound around the core 3a are housed and held inside the ceiling top of the house 1 has been described. It is needless to say that the transparent member 5 can be stretched in the same manner even when is stored and held inside the ceiling top.

FIG. 3 is an explanatory view showing another embodiment in which a transparent material made of a transparent film is stretched.

In this embodiment, one end of the transparent material 5 is fixed to a beam 7 fixing one end of the agricultural curtain material 3 and one end of the wire 6, and the other end is provided along the longitudinal direction of the house 1. Is wound around the wound core 5a and is rolled and stored and held below the agricultural curtain material 3, specifically, between one of the stored and held agricultural curtain materials 3 and the wire 6. (FIG. 3 (a)).

However, when the agricultural curtain material 3 is used, the agricultural curtain material 3 is covered so as to cover the transparent material 5 which is rolled and held below one agricultural curtain material 31.
1 is stretched along the wire 6 (FIG. 3B) to adjust the environment in the house. When the agricultural curtain material 3 is not used, the transparent material 5 that is rolled and held is expanded with respect to the agricultural curtain material 3 that is wound up and held and held by the core 3a as shown in FIG. The covering is performed so as to cover the one agricultural curtain material 32 from above the other agricultural curtain material 32 (FIG. 3C).

In order to cover the transparent material 5 in this manner, a rotating machine and a handle (not shown) are provided at one end of the core 5a, and the core 5a is moved from the state of FIG. What is necessary is just to make it rotate to the state of c).

When the transparent material 5 is coated as described above, the transmitted light of the transparent material 5 is irradiated only to the agricultural curtain material 3 and the irradiation of the cultivated crop 4 below can be reduced as much as possible. The effect of the transmitted light 5 on the cultivated crop 4 can be minimized.

Also in this embodiment, the transparent material 5 can be similarly coated even if only one agricultural curtain material 3 is used.

[0053]

Hereinafter, embodiments of the present invention will be described.
The present invention is not limited by such embodiments.

In the experimental farm of Mikado Kako Co., Ltd. for agricultural use (Ichihara City, Chiba Prefecture), “Super Solar” (trade name of Mikado Kako Co., Ltd., average UV transmittance 75%) was used as a material for cultivating house. Six agricultural houses with a frontage of 4.5 m and a length of 15 m were provided.

[0055] as an agricultural curtain materials agricultural curtain material, "Sansofuta" (Mikado trade name of Chemical Co., Ltd., polyester) wound around the core using a ceiling of each of the agricultural house, as shown in Figure 1 Each was placed inside the top.

Production of Transparent Materials 1 to 6 Low-density polyethylene was used as the polyolefin resin, and the average transmittance of ultraviolet light, the average transmittance of visible light, and the value of HAZE in the resin were as shown in Table 1. So that
UV absorber: the amount of benzophenone added, inorganic filler:
The amount of zeolite added was adjusted, and film-like transparent materials 1, 2, 5, and 6 having a thickness of 50 µm, a length of 15 m and a width of 1 m were obtained by inflation extrusion molding.

A commercially available general agricultural film (thickness: 50)
μm, length 15 m × width 1 m) to obtain a transparent material 3.

Further, a transparent material 4 was obtained by using a commercially available ultraviolet-permeable agricultural plastic film (thickness: 50 μm, length: 15 m × width: 1 m).

These transparent materials 1 to 6 are distributed to the six agricultural houses, respectively.
It was stretched as shown in FIG.

Evaluation Each of the agricultural houses on which the transparent materials 1 to 6 were stretched was used for eight months from March 8, 1999 to November 8, 1999, and then used for agricultural purposes. Regarding the situation of the strength reduction of the curtain material, the tear propagation resistance was measured and evaluated as follows. Note that the tear propagation resistance is a resistance expressed in kg when the agricultural curtain material is cut and torn.

○: 1 kg or more ×: 0.5 kg or more and less than 1 kg XX: less than 0.5 kg

[0062]

[Table 1]

The transparent members 5 and 6 were unsuitable for being stretched in an agricultural house because the transparent members themselves formed shadows.

[0064]

As described above, according to the present invention, a method for further improving the durability compared with the conventional agricultural curtain material can be realized at a low cost without destroying the suitable environment of the cultivated crop formed by the film for a house. Can be provided.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an outline of a configuration of an agricultural house to which the present invention is applied.

FIG. 2 is an explanatory view showing a mode of stretching a transparent material.

FIG. 3 is an explanatory view for explaining another stretching mode of a transparent material.

[Explanation of symbols]

 1: Agricultural house 2: House cultivation material 3: Agricultural curtain material 3a: Core 4: Cultivated crop 5: Transparent material 6: Wire 7: Beam 31: One agricultural curtain material 32: The other agricultural curtain Material a: Beam

Claims (3)

[Claims] 1. A weave formed using a synthetic resin material inside a ceiling top of an agricultural house formed using a material for house cultivation having an average transmittance of ultraviolet rays (wavelength of 350 nm or less) of 50% or more. In an agricultural house in which an agricultural curtain material made of cloth or nonwoven fabric is stored and held when not in use, an average transmittance of visible light (wavelength: 400 nm to 700 nm) between the house cultivation material and the agricultural curtain material. Is 85 to 95%, the average transmittance of ultraviolet rays (wavelength 350 nm or less) is 50% or less, and HAZE is 1 to 5%.
0. A deterioration of agricultural curtain material characterized by interposing a transparent material having a characteristic of 0 and irradiating the agricultural curtain material with sunlight adjusted in the amount of ultraviolet light and the amount of direct light by the transparent material. Prevention method. 2. The method according to claim 1, wherein the transparent material is disposed above the stored agricultural curtain material in any of a triangular shape, a curved shape, and a horizontal shape when viewed from the longitudinal direction of the agricultural house. A method for preventing deterioration of agricultural curtain materials according to claim 1. 3. A transparent material made of a transparent film is rolled and held on the lower side of the agricultural curtain material in a storage and holding portion of the agricultural curtain material, and the transparent material is stored in the stored and held agricultural curtain material. 2. The method for preventing deterioration of agricultural curtain materials according to claim 1, wherein the agricultural curtain materials are covered so as to cover the agricultural curtain materials.