JP2016185116A - Agricultural House - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an agricultural house that inhibits condensation inside a lining film and also has a high light transmittance.SOLUTION: An agricultural house 10 comprises an outer coating film 1 that forms a space separated from the outside, a lining film 2 provided inside the outer coating film so as to have a gap with the outer coating film, and ventilation means 4 for ventilation between at least part of the air in the gap and the outside air. At least part of the lining film is composed of a cellulose film that comprises cellulose acylate resin and has a moisture permeability of 600 g/m/24 h or more.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an agricultural house.

In order to prevent low temperatures in winter, a double-structured agricultural house with a double film is known.
For example, Patent Document 1 discloses that “at least two synthetic resin sheets are arranged so as to cover the entire side surface of an agricultural house and are fused in a horizontal direction at predetermined intervals in the vertical direction. In the heat insulating sheet in which a plurality of air flow path portions are formed, each heat-sink portion of the synthetic resin sheet is provided with a plurality of drainage portions communicating with the respective air flow paths at a predetermined interval in the horizontal direction. Sheet ”([Claim 1]), the outer synthetic resin sheet is a non-permeable sheet, and the inner synthetic resin sheet has a large number of micropores. The aspect which is the formed air-permeable sheet | seat is described ([Claim 3] [Claim 4]).

JP 2011-10590 A

  When the present inventors examined the heat insulating sheet described in Patent Document 1, as a synthetic resin sheet (lining film) positioned on the inner side, a sheet having air permeability in which micropores are formed is used. Is not enough to prevent dew condensation on the inner side of the seat (inside the agricultural house) due to the temperature difference, and also reduces the light transmittance, hindering the growth of plants and the warming effect in the agricultural house. It turns out that there is a possibility of being.

  Then, this invention makes it a subject to suppress the dew condensation inside a lining film and to provide an agricultural house with a high light transmittance.

The present inventors have made intensive studies to achieve the above object, comprises a cellulose acylate resin, moisture permeability using cellulose film is 600g / m ² / 24h or more as lining films, lining film and the outer clad It has been found that by providing a ventilation means for ventilating the air existing in the gap with the film, condensation inside the lining film can be suppressed and the light transmittance can be increased, and the present invention has been completed.
That is, it has been found that the above-described problem can be achieved by the following configuration.

[1] An outer film that forms a space partitioned from the outside, an inner film that is provided inside the outer film so as to have a gap with the outer film, at least a part of the air that exists in the gap, and the outside Ventilation means for ventilating the air of
Lining at least a portion of the film contains a cellulose acylate resin, moisture permeability is composed of cellulose film or 600g / m ² / 24h, agricultural house.
[2] At least a part of the outer film is provided with ventilation means,
Ventilation means is a moisture permeability of more than 500g / m ² / 24h films, agricultural house according to [1].
[3] Ventilation means contains a cellulose acylate resin, moisture permeability is a cellulose film described above 600 g / m ² / 24h, agricultural house according to [2].
[4] The agricultural house according to any one of [1] to [3], wherein the roof portion of the lining film is made of a cellulose film.

  ADVANTAGE OF THE INVENTION According to this invention, the dew condensation inside a lining film can be suppressed and an agricultural house with a high light transmittance can be provided.

FIG. 1 is a schematic partially cutaway perspective view showing an example of the appearance of an agricultural house according to the present invention. FIG. 2 is a schematic cross-sectional view showing an example of the inside of the agricultural house of the present invention. FIG. 3 is a schematic cross-sectional view showing an example of the inside of the agricultural house of the present invention. FIG. 4 is a schematic cross-sectional view showing an example of the inside of the agricultural house of the present invention.

Hereinafter, the present invention will be described in detail.
The description of the constituent elements described below may be made based on typical embodiments of the present invention, but the present invention is not limited to such embodiments.
In the present specification, a numerical range expressed using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.

The agricultural house of the present invention includes an outer film that forms a space partitioned from the outside, an inner film that is provided inside the outer film so as to have a gap, and at least air that exists in the gap. Ventilation means for ventilating a part and external air. In the present invention, as will be described later, a part of the outer film may be provided with ventilation means, or the entire outer film may be provided with ventilation means.
Moreover, the lining film in the agricultural house of this invention is a film comprised at least one part of the cellulose film which contains a cellulose acylate resin and whose water vapor transmission rate is 600 g / m < ² > / 24h or more.

FIG. 1 is a schematic partially cutaway perspective view showing an example of the appearance of an agricultural house of the present invention, and FIGS. 2 to 4 are schematic sectional views showing an example of the interior of the agricultural house of the present invention. is there.
As shown in FIGS. 1 to 4, the agricultural house 10 includes an outer film 1 and an inner film 2 (reference numeral 2a: roof portion, reference numeral 2b: wall surface portion).
In addition, as shown in FIG. 1, the outer film 1 is preferably in a form stretched by a casing 3.
Moreover, although the agricultural film 10 shown in FIGS. 1-3 shows the aspect in which the outer film 1 at least partially served as the ventilation means, as shown in FIG. You may provide the ventilation fan 4 comprised by these.

Agricultural house of the present invention, the above-described configuration, in particular, contains a cellulose acylate resin, moisture permeability using cellulose film is 600g / m ² / 24h or more as lining films, the gap between the lining film and the outer clad film By providing a ventilation means for ventilating the air present in the housing, condensation inside the lining film can be suppressed and the light transmittance of the agricultural house can be increased.
The reason for the effect is not clear in detail, but the present inventors presume as follows.
First, in the sheet | seat which has the air permeability in which the micropore described in patent document 1 was formed, since the moisture permeability was raised by presence of a pore, it has the effect of reducing the humidity in an agricultural house. However, once condensation occurs, it is thought that condensation blocks pores and impairs moisture permeability, and light transmittance is considered to be lowered due to the presence of condensation and pores themselves.
In contrast, in the present invention, by containing the cellulose acylate resin, it improves the moisture absorption of the lining film for hydrophilicity is high, also the moisture permeability is at 600g / m ² / 24h or more By doing this, the in-plane distribution of moisture permeability in the lining film is substantially eliminated, and the occurrence of condensation itself can be suppressed or the condensation once generated can be efficiently eliminated, thereby suppressing the condensation inside the lining film, And it is thought that the light transmittance of an agricultural house can be made high.

  Below, the lining film, the lining film, the ventilation means, etc. which comprise the agricultural house of this invention are explained in full detail.

[Lining film]
The lining film of the agricultural house of the present invention is a film provided so as to have a gap with the lining film inside the lining film described later, and at least a part thereof contains a cellulose acylate resin and has a moisture permeability. it is composed film cellulose film than 600g / m ² / 24h.
Here, the moisture permeability is 24 hours under the conditions of a temperature of 40 ° C. and a relative humidity of 90% according to the method described in “Moisture permeability test method of moisture-proof packaging material (cup method)” of JIS Z 0208: 1976. It refers to the amount of water vapor passing through ^{(g / m 2 / 24h)} .

<Cellulose acylate resin>
The cellulose acylate resin contained in the cellulose film is not particularly limited, and is a cellulose acylate containing a conventionally known aliphatic acyl group having 2 to 22 carbon atoms (for example, acetyl group, propionyl group, butyryl group, pentanoyl group, etc.). Rate resin; Cellulose acylate resin containing at least one kind of unsubstituted aromatic acyl group; and the like can be used.
In addition, it is preferable to contain 60-90 mass% of cellulose acylate resin with respect to the total mass of a cellulose film from a viewpoint of hold | maintaining the moisture permeability mentioned above, and it is containing 65-80 mass%. More preferred.

Examples of the raw material cellulose of the cellulose acylate resin include cotton linter, kenaf, wood pulp (hardwood pulp, softwood pulp) and the like. These may be used alone or in combination of two or more. Good.
Of these, the raw material cellulose is preferably cotton linter and / or wood pulp.
Moreover, it is preferable that cotton linter and / or wood pulp contain 80% or more of α-cellulose.
Further, the cotton linter and / or wood pulp is preferably mannose / xylose = 0.35 / 1 to 3.0 / 1 (molar ratio), and the total content thereof is 0.01 to 5 mol%. It is preferable.
In addition, it is preferable that the mixing ratio in the case of using together cotton linter and wood pulp is 5 / 95-95 / 5.

The cellulose acylate constituting the cellulose acylate resin is a carboxylic acid ester of cellulose, for example, preferably a lower carboxylic acid ester of cellulose.
Specific examples of the cellulose acylate include cellulose acetate, cellulose acetate propionate, cellulose acetate butyrate, cellulose acetate stearate, and cellulose acetate benzoate.
Among these, cellulose acetate is preferable, and specifically, triacetyl cellulose (TAC) is more preferable.

Such cellulose acylate is produced by a combination of an activation process (pretreatment process), an acylation process (acetylation process in the case of acetyl), an aging process, a precipitation process, a purification process, a drying process, and a pulverization process. It is preferred that
The cellulose acylate raw material cotton and the synthesis method are also described in detail on pages 7 to 12 of the Japan Society for Invention and Technology (public technical number 2001-1745, published on March 15, 2001, Japan Institute of Invention). ing.

Moreover, it is preferable that the viscosity average polymerization degree (DP) of a cellulose acylate is 200-700.
Moreover, it is preferable that the ratio (Mw / Mn) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) of cellulose acylate is 1.0 to 5.0, and is 1.0 to 4.0. Is more preferable, and it is still more preferable that it is 1.5-3.0.
Here, the viscosity average polymerization degree refers to an average molecular weight according to a viscosity method (ASTM D2857), and the weight average molecular weight and the number average molecular weight refer to molecular weights measured by a gel permeation chromatography (GPC) method, respectively.

  In the cellulose acylate, the amount of residual acetic acid or the amount of residual carboxylic acid having 3 to 22 carbon atoms is preferably 0.5% by mass or less.

  In addition, the cellulose acylate preferably contains 1 ppb to 10,000 ppm of at least one of alkali metals and / or alkaline earth metals.

  In addition, the cellulose acylate preferably has an acetone extraction amount at 25 ° C. of 15% by mass or less.

  Moreover, it is preferable that a cellulose acylate contains the acid of acid dissociation index 1.93-4.5, or a partially esterified substance, or these salts.

Moreover, it is preferable that the moisture content of a cellulose acylate is 2 mass% or less.
Moreover, it is preferable that the yellowness index of a cellulose acylate is 0.1-10.

Moreover, it is preferable that the haze of a cellulose acylate is 0.05 to 5%.
Moreover, it is preferable that the light transmittance of a cellulose acylate is 80% or more.

Moreover, it is preferable that Tg of a cellulose acylate is 80-200 degreeC.
Moreover, it is preferable that the crystallization calorific value of a cellulose acylate is 2-20 J / g.

In the present invention, the cellulose acylate preferably has a degree of substitution with a hydroxyl group of cellulose satisfying the following formulas (1) and (2).
2.0 ≦ SA + SB ≦ 3.0 Formula (1)
0 ≦ SA ≦ 3.0 Formula (2)
Here, in the formula, “SA” represents the degree of substitution of the acetyl group substituting the hydrogen atom of the cellulose hydroxyl group, and “SB” is other than the acetyl group substituting the hydrogen atom of the hydroxyl group of cellulose. Represents the substitution degree of the acyl group.
Moreover, it is preferable that said Formula (2) is represented by following formula (3) from the reason for which the workability of the cellulose film obtained becomes more favorable.
2.5 ≦ SA ≦ 3.0 Formula (3)

<Additives>
The cellulose film may contain additives such as a plasticizer, a matting agent, a deterioration preventing agent, and an ultraviolet absorber depending on the use environment.
Specific examples of the plasticizer include an ester plasticizer including a polyether ester represented by the following formula (A) and an ether plasticizer including a polyether represented by the following formula (B). It is mentioned in.
In the above formula (A), R ¹ represents a divalent aliphatic hydrocarbon group having 2 to 10 carbon atoms, R ² each independently represents a divalent aliphatic hydrocarbon group having 2 to 6 carbon atoms, R ³ each independently represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an acyl group having 2 to 20 carbon atoms. n represents the integer of 1-20 each independently, and p represents the integer of 1-15. A plurality of R ¹ , R ² and n contained in the repeating unit may be the same or different.
In the above formula (B), R ⁴ represents a divalent aliphatic hydrocarbon group having 2 to 6 carbon atoms, R ⁵ and R ⁶ are each independently a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, It represents a group represented by the following formula (b) in which an aryl group having 6 to 20 carbon atoms, an acyl group having 2 to 20 carbon atoms, a (meth) acryloyl group, or a (meth) acryloyl group is polymerized. m represents an integer of 1 to 20. The plurality of R ⁴ contained in the repeating unit may be the same or different.
Here, in this specification, “(meth) acryloyl group” means an acryloyl group (CH ₂ ═CHCO—) or a methacryloyl group (CH ₂ ═C (CH ₃ ) CO—).
In the above formula (b), * represents an oxygen atom bonded to R ⁵ or R ⁶ in the above formula (B), R ⁷ represents a hydrogen atom or a methyl group, and q represents an integer of 1 to 10. A plurality of R ⁷ contained in the repeating unit may be the same or different.

  In the present invention, the content in the case of containing a plasticizer is preferably 10 to 70 parts by mass, more preferably 20 to 60 parts by mass with respect to 100 parts by mass of the cellulose acylate resin. More preferably, it is -60 mass parts, and it is especially preferable that it is 40-60 mass parts.

As the matting agent, either organic or inorganic fine particles can be used.
Specific examples of the deterioration inhibitor include hindered amine light stabilizers, antioxidants, peroxide decomposers, radical inhibitors, metal deactivators, acid scavengers, amines, and the like. .
Moreover, as an ultraviolet absorber, what can express ultraviolet absorptivity can be expressed and any well-known thing can be used, for example, a benzotriazole type | system | group and a hydroxyphenyl triazine type ultraviolet absorber are mentioned suitably.
When such an additive is added, it is preferably contained in a cellulose acylate solution (dope) described later.

<Method for producing cellulose film>
The production method for producing the cellulose film is not particularly limited. For example, the dope (cellulose acylate solution) in which cellulose acylate is dissolved in an organic solvent is used to form an endless belt or a drum that rotates in a casing from a casting die. Examples include a solution casting method in which a film is cast on a support (hereinafter collectively referred to as “support”), peeled off from the support, and further dried to form a film.

(Organic solvent)
Examples of organic solvents that dissolve cellulose acylate include hydrocarbon solvents such as benzene and toluene; halogenated hydrocarbon solvents such as methylene chloride and chlorobenzene; alcohol solvents such as methanol, ethanol, and diethylene glycol; acetone and the like Ketone solvents; ester solvents such as methyl acetate, ethyl acetate, and propyl acetate; ether solvents such as tetrahydrofuran and methyl cellosolve; and the like. These may be used alone or in combination of two or more. May be.

Among these, it is preferable to use a halogenated hydrocarbon solvent having 1 to 7 carbon atoms, and it is more preferable to use methylene chloride.
Moreover, it is preferable to use together C1-C5 alcohol other than a methylene chloride from viewpoints, such as the solubility of a cellulose acylate, the peelability from a support body, and the mechanical strength of a film. 2-25 mass% is preferable with respect to the whole solvent, and, as for content of alcohol, 5-20 mass% is more preferable. Specific examples of the alcohol include methanol, ethanol, n-propanol, isopropanol, n-butanol, and the like, and methanol, ethanol, n-butanol, or a mixture thereof is preferably used.

(Preparation of cellulose acylate solution)
The cellulose acylate solution is prepared by first mixing cellulose acylate and an organic solvent, dissolving cellulose acylate at −10 to 55 ° C., and adding a mixture of the dissolved portion, the undissolved portion and the organic solvent to 0 to A preparation method in which the cellulose acylate is completely dissolved in a solvent by heating to 97 ° C. is preferable.
Here, the prepared cellulose acylate solution may be concentrated as necessary, but the cellulose acylate preferably has a concentration of 5 to 40% by mass. The cellulose acylate solution preferably has a viscosity at 40 ° C. of 10 to 3000 Pa · s.

  In addition, when the cellulose acylate and the organic solvent are mixed, it is preferable to use particles in which 90% by mass or more of the cellulose acylate is 0.1 to 4 mm.

Moreover, it is preferable to filter a cellulose acylate solution at the temperature of 0-200 degreeC before casting.
Here, the average pore size of the filtration filter is preferably 100 μm or less, and the filtration flow rate is preferably 50 liters / hr or more.

(Casting)
In the step of casting the cellulose acylate solution, the solution temperature is preferably −10 to 57 ° C., and the temperature of the step is preferably kept at −10 to 57 ° C.
Moreover, it is preferable that the support body which casts a cellulose acylate solution has a surface temperature of -20-40 degreeC.

(Stripping)
The stripping after casting is preferably performed at a temperature of 20 to 250 ° C. at the time of stripping. Moreover, it is preferable that the undried cellulose film at the time of drying is hold | maintained with a tenter.

The cellulose film produced by such solution casting is preferably stretched by 0.5 to 300% at least during uniaxial casting or after casting. The casting speed is preferably 1 to 200 m / min.
The cellulose film preferably has a wound form of at least 100 m in the longitudinal direction and 60 cm or more in the width direction.

  In the present invention, the method for producing the above-described cellulose acylate film is not particularly limited, and a known method other than the above-described method can be appropriately employed. For example, JIII Journal of Technical Disclosure (Publication No. 2001-1745). The method described on pages 12 to 30 of the Japan Society for Invention and Innovation (issued on March 15, 2001) can be appropriately employed.

In the present invention, it is preferable that the roof portion of the lining film is composed of the above-mentioned cellulose film for the reason of preventing plant growth failure due to dripping of condensation, and both the roof portion and the wall surface portion of the lining film are More preferably, it is composed of the cellulose film described above.
Here, the roof portion of the lining film refers to an upper portion of a space in which plants are grown, that is, a portion positioned in a direction perpendicular to the soil on which the plants are placed, and is represented by reference numeral 2a in FIGS. The part to be done.
Moreover, the wall surface part of a lining film means the side part of the space which grows a plant, ie, the part located in a horizontal direction with respect to the soil etc. in which the plant was placed, and it represents with the code | symbol 2b in FIGS. The part to be done.

In addition, the thickness of the lining film is preferably 60 μm to 200 μm, more preferably 80 μm to 150 μm, and even more preferably 80 μm to 120 μm, from the reason that processability is good.
The lining film may have a single layer structure or a laminated structure, but preferably has a single layer structure.

[Outer film]
The outer film which the agricultural house of this invention has is a film which forms the space partitioned off from the outside.

  The outer film is not particularly limited, and examples of the constituent material thereof include polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polyethylene, acrylic resin, polyvinyl chloride, polyvinyl alcohol, cellulose acylate resin, and fluorine-containing resin. .

In the present invention, maintaining the moisture permeability, for reasons that can further suppress the occurrence of condensation, at least a portion of the outer clad film is provided with a ventilator, which will be described later, the ventilation means, moisture permeability 500g / m ² / 24h The above film is preferable.
Here, “at least a part of the outer film is provided with a ventilation means described later” means that at least a part of the outer film has at least a part of the air existing in the gap between the outer film and the outer film and the outside. In this case, there is no ventilation means (for example, the ventilation fan 4 shown in FIG. 4) configured separately from the outer film. Also good.
Note that “all the outer film has a ventilation means described later” means that the entire outer film ventilates at least part of the air existing in the gap between the outer film and the inner film and the external air. In this case, the outer film and the ventilation means are constituted by the same member.

Examples of the film having a moisture permeability of 500 g / m ² / 24h or more include an agricultural film described in Japanese Patent Application Laid-Open No. 2007-089493, a cellulose film described as the above-described lining film, and the like.
Among these, there is no intrusion of water droplets due to rainfall, and the reasons light transmittance becomes higher, contains a cellulose acylate resin, and even a cellulose film moisture permeability 600g / m ² / 24h or more preferable.

[Ventilation means]
The ventilation means which the agricultural house of the present invention has is a means for ventilating at least part of the air present in the gap between the above-described outer film and the inner film and the outside air.
Here, as described above, the ventilation means is configured as an aspect provided in at least a part of the above-described outer film, that is, a film having a moisture permeability of 500 g / m ² / 24h or more, or a separate body from the outer film. The member (for example, a ventilation fan, a vent hole, etc.) etc. are mentioned.

[Body]
The agricultural house of the present invention may have a housing for spreading the above-described outer film and inner film (particularly, the outer film).
Here, a housing is not specifically limited, The aggregate (for example, steel materials, a steel pipe, etc.) used in a conventionally well-known greenhouse etc. can be used.

In the present invention, the method for installing the above-described lining film on the inside of the above-described outer-film is not particularly limited. For example, after an agricultural house is manufactured using the outer-film and the casing, Method of making a small agricultural house using a lining film and a frame; after creating an agricultural house using an outer film and a frame, a curtain rail and a wire are installed near the boundary between the roof and the wall of the agricultural house And a method of installing an inner film on these.
In addition, the lining film is preferably installed on a curtain rail or the like so as to be movable, from the viewpoint of being able to be installed at nighttime or early morning hours when the outside air temperature decreases.
Further, the gap between the above-mentioned outer film and the outer film when installing the inner film need not be constant. For example, as shown in FIG. 3, only the roof part of the inner film may be installed horizontally. Good.

  Hereinafter, the present invention will be described in more detail based on examples. The materials, amounts used, ratios, processing details, processing procedures, and the like shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the following examples.

[Production of Triacetyl Cellulose (TAC) Film]
<Preparation of dope>
The following composition was put into a mixing tank and stirred to dissolve each component to prepare a cellulose acetate solution.
-------------------------------------------------- ------------------------------
Cellulose acylate (acetyl group substitution degree: 2.86, viscosity average polymerization degree: 320)
100 parts by mass / silica particle dispersion (average particle size 16 nm)
"AEROSIL R972", manufactured by Nippon Aerosil Co., Ltd. 1.3 parts by mass, methylene chloride 635 parts by mass, methanol 1.3 parts by mass
-------------------------------------------------- ------------------------------

<Formation of TAC film>
Using a dope whose temperature was adjusted to 30 ° C., the film was uniformly cast on an endless stainless steel belt (support) so that the film thickness after drying was 100 μm.
Immediately after casting, the dope film (web) on the belt was dried by applying hot air at 100 ° C., and then 120 seconds after casting, the film was peeled off at a peeling tension of 150 N / m, and a conveying tension of 100 N with many rolls. It was dried while being conveyed at / m. The temperature of the endless stainless steel belt at the peeling portion was 10 ° C. The amount of residual solvent at the time of peeling was 100% by mass.
The first drying zone set at 80 ° C. was transported for 5 minutes, and further transported for 10 minutes in the second drying zone set at 120 ° C. for drying. After drying, a TAC film having a film width of 1.5 m, a winding length of 2000 m, and a film thickness of 100 μm was obtained by winding up into a roll. The residual solvent amount at the time of winding was 0.3%.

[Fluorine film]
The product name “Efclean (registered trademark) natural light drop” manufactured by AGC Greentech was used as the fluorine film.

[Porous polyolefin (porous PO) film]
The product name “Comfort Air Drying” manufactured by Mitsubishi Plastics Agridream was used as the pore PO film.

[Examples 1 to 5 and Comparative Examples 1 to 4 and Reference Examples 1 to 2]
<Production of agricultural house>
At Miyadai, Minamiashigara City, a framework of 6.0m x 9.0m x 4.0m (height) was built, and an outer film shown in Table 1 below was spread on the frame to produce an agricultural house.
Next, a 5.8 m x 8.8 m x 3.8 m (height) framework was built inside the produced agricultural house, and the agricultural film was produced by spreading the lining film shown in Table 1 below on the housing. .
In Table 1, the TAC film is described as “TAC / fluorine-based” as the lining film, as shown in the following Table 1, a TAC film is used for the roof portion of the lining film, and the wall surface portion of the lining film is fluorine-based. Indicates that a film was used.
In Reference Examples 1 and 2, an agricultural house in which only the outer film was spread was used without using the inner film.

About the produced agricultural house, it measured or evaluated by the method shown below about the water vapor transmission rate and light transmittance of a lining film and an outer lining film. These results are shown in Table 1 below.
Moreover, about the produced agricultural house, at 8 o'clock in the morning on a clear day in November 2014, it was visually confirmed whether or not condensation had occurred inside the lining film, and at 18:00 after sunset on the same day. Then, the temperature and relative humidity in the agricultural house were measured. These results are also shown in Table 1 below.

<Moisture permeability>
For each film, in accordance with the method described in “Moisture permeability test method for moisture-proof packaging material (cup method)” of JIS Z 0208: 1976, the water vapor that passed for 24 hours under the conditions of a temperature of 40 ° C. and a relative humidity of 90% was used. the amount (g / m ² / 24h) was measured.
In Table 1 below, Examples 3 and 5 show the moisture permeability of the TAC film used for the roof portion of the lining film.

<Light transmittance>
About each film, the transmittance | permeability of the visible-light area | region of 400-700 nm was measured using the spectrophotometer (the product made by Jusco Engineering: V-560), and the average value was computed.
And the value which multiplied the average transmittance | permeability of the lining film and the lining film is evaluated as "A" as the light transmittance of the agricultural house is high, and it is 60% or more and less than 80%. Those with a light transmittance of the agricultural house were evaluated as “B”, and those with less than 60% were evaluated as “C” with a light transmittance of the agricultural house being low.

As shown in Table 1, when a fluorine-based film was used as the lining film, it was found that condensation occurs and the light transmittance is low regardless of the presence or absence of ventilation means (Comparative Example 1 and 2).
Further, even when the moisture permeability as lining films with more TAC film 600g / m ² / 24h, when not having the ventilation means were found not it is possible to suppress the generation of dew condensation (Comparative Example 3 ).
In addition, assuming that Patent Document 1 is used and the pore PO film is used as the lining film, it is found that condensation occurs and the light transmittance is low even if a ventilation means is provided ( Comparative Example 4).

On the other hand, if the moisture permeability at least a portion of the lining film with 600g / m ² / 24h or more TAC film, having a ventilation means suppresses the inner condensation lining film, and the light transmittance is high (Examples 1-5).
In particular, in Examples 1 to 3, in which the TAC film was also used as the outer film, the outer film itself also serves as a ventilation means, and thus it was found that the relative humidity in the house can be lowered regardless of the presence or absence of a ventilation fan. .

DESCRIPTION OF SYMBOLS 1 Outer film 2 Inner film 2a Roof part of lining film 2b Wall part of lining film 3 Housing 4 Ventilation fan 10 Agricultural house

Claims (4)

An outer film that forms a space partitioned from the outside, an inner film that is provided inside the outer film so as to have a gap with the outer film, at least a part of the air that exists in the gap, and the outside Ventilation means for ventilating the air of
At least a portion of the lining film, contains a cellulose acylate resin, moisture permeability is composed of cellulose film or 600g / m ² / 24h, agricultural house. At least a part of the outer film comprises the ventilation means,
It said ventilation means, moisture permeability is more film 500g / m ² / 24h, agricultural house according to claim 1. It said ventilation means comprises a cellulose acylate resin, moisture permeability is a cellulose film described above 600 g / m ² / 24h, agricultural house according to claim 2.   The agricultural house according to any one of claims 1 to 3, wherein a roof portion of the lining film is composed of the cellulose film.