U.S. patent application number 16/784596 was filed with the patent office on 2020-06-04 for film for agricultural greenhouse and agricultural greenhouse.
This patent application is currently assigned to FUJIFILM Corporation. The applicant listed for this patent is FUJIFILM Corporation. Invention is credited to Akihiro IKEYAMA, Eiji ISHII, Shogo KATANO, Yui OMI, Kimito WASHIYA.
Application Number | 20200170196 16/784596 |
Document ID | / |
Family ID | 56149934 |
Filed Date | 2020-06-04 |
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United States Patent
Application |
20200170196 |
Kind Code |
A1 |
KATANO; Shogo ; et
al. |
June 4, 2020 |
FILM FOR AGRICULTURAL GREENHOUSE AND AGRICULTURAL GREENHOUSE
Abstract
Objects of the present invention are to provide a film for an
agricultural greenhouse that can maintain a CO.sub.2 concentration
necessary for the photosynthesis of plants even when ventilation is
not performed and to provide an agricultural greenhouse using the
film. The film for an agricultural greenhouse of the present
invention is a cellulose film which contains a cellulose acylate
resin and has an equilibrium moisture content of 4% to 8% at a
temperature of 25.degree. C., a relative humidity of 80% and a
thickness of 60 to 200 .mu.m.
Inventors: |
KATANO; Shogo; (Kanagawa,
JP) ; OMI; Yui; (Kanagawa, JP) ; WASHIYA;
Kimito; (Kanagawa, JP) ; IKEYAMA; Akihiro;
(Kanagawa, JP) ; ISHII; Eiji; (Kanagawa,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
FUJIFILM Corporation |
Tokyo |
|
JP |
|
|
Assignee: |
FUJIFILM Corporation
Tokyo
JP
|
Family ID: |
56149934 |
Appl. No.: |
16/784596 |
Filed: |
February 7, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15628131 |
Jun 20, 2017 |
10595472 |
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16784596 |
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PCT/JP2015/080215 |
Oct 27, 2015 |
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15628131 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08K 9/12 20130101; A01G
9/1438 20130101; C08L 1/10 20130101; Y02A 40/268 20180101; A01G
13/02 20130101; A01G 9/1415 20130101; A01G 9/18 20130101; C08J 5/18
20130101; A01G 9/246 20130101; C08L 1/02 20130101; C08L 1/12
20130101; Y02A 40/252 20180101; Y02A 40/25 20180101; C08J 2301/12
20130101; C08J 2301/10 20130101 |
International
Class: |
A01G 9/14 20060101
A01G009/14; C08L 1/12 20060101 C08L001/12; A01G 9/18 20060101
A01G009/18; A01G 13/02 20060101 A01G013/02; C08J 5/18 20060101
C08J005/18; C08K 9/12 20060101 C08K009/12; C08L 1/02 20060101
C08L001/02; C08L 1/10 20060101 C08L001/10 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 26, 2014 |
JP |
2014-265310 |
Mar 27, 2015 |
JP |
2015-067332 |
Mar 27, 2015 |
JP |
2015-067456 |
Claims
1. An agricultural greenhouse comprising: a covering film which
forms a space walled off from the outside, a lining film which is
provided on the inside of the covering film such that an interspace
is formed between the covering film and the lining film, and a
ventilation means for exchanging at least a portion of the air
existing in the interspace with the external air, wherein at least
a portion of the lining film is constituted with a cellulose film
which contains a cellulose acylate resin and has a water vapor
permeability equal to or higher than 600 g/m.sup.2/24 h.
2. The agricultural greenhouse according to claim 1, wherein at
least a portion of the covering film includes the ventilation
means, and the ventilation means is a film having a water vapor
permeability equal to or higher than 500 g/m.sup.2/24 h.
3. The agricultural greenhouse according to claim 2, wherein the
ventilation means is the cellulose film which contains a cellulose
acylate resin and has a water vapor permeability equal to or higher
than 600 g/m.sup.2/24 h.
4. The agricultural greenhouse according to claim 1, wherein a roof
portion of the lining film is constituted with the cellulose
film.
5. The agricultural greenhouse according to claim 2, wherein a roof
portion of the lining film is constituted with the cellulose
film.
6. The agricultural greenhouse according to claim 3, wherein a roof
portion of the lining film is constituted with the cellulose film.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a Continuation of U.S.
application Ser. No. 15/628,131, filed on Jun. 20, 2017, which is a
Continuation of PCT International Application No. PCT/JP2015/080215
filed on Oct. 27, 2015, which was published under PCT Article 21(2)
in Japanese, and which claims priority under 35 U.S.C. .sctn.
119(a) to Japanese Patent Application No. 2014-265310 filed on Dec.
26, 2014, Japanese Patent Application No. 2015-067332 filed on Mar.
27, 2015 and Japanese Patent Application No. 2015-067456 filed on
Mar. 27, 2015. The above applications are hereby expressly
incorporated by reference, in their entirety, into the present
application.
BACKGROUND OF THE INVENTION
1. Field of the Invention
[0002] The present invention relates to a film for an agricultural
greenhouse and an agricultural greenhouse.
2. Description of the Related Art
[0003] Regarding an agricultural greenhouse using a transparent
film which contains vinyl chloride, polyethylene, a
polyethylene-vinyl acetate copolymer, polyethylene terephthalate
(PET), a polyethylene-tetrafluoroethylene copolymer, or the like as
a main material, it is known that, during the daytime in summer or
the like, the internal temperature of the greenhouse increases up
to 40.degree. C. or higher due to the solar radiation heat
resulting from sunlight. Furthermore, it is known that, during the
daytime in winter or the like, the inside of the greenhouse cannot
be effectively thermally insulated by only the solar radiation heat
resulting from sunlight.
[0004] Therefore, for the daytime in summer, a method of cooling
the internal air within the greenhouse by using an air conditioner,
a method of scattering water droplets (mist) inside the greenhouse
by using a mist cooling device (for example, a mist fan or a mist
cooler) such that the inside of the greenhouse is cooled by the
heat of vaporization, and the like are known (for example, see
JP2010-17093A).
[0005] Furthermore, for the daytime in winter, a method of
supplying heat to the inside of the greenhouse from a heat source
such as a heater so as to inhibit the decrease in temperature and
the like are known.
[0006] For example, JP2010-17093A describes "an air conditioning
method for a greenhouse, comprising installing a circulation fan in
the vicinity of an exhaust port of an indoor unit of a heat pump of
an air conditioning device of a greenhouse in which the indoor unit
of the heat pump is installed on the inside of the greenhouse, such
as a hothouse or a plastic greenhouse, and an outdoor unit of the
heat pump is installed on the outside of the greenhouse, sending
hot air or cold air by the circulation fan to the circulation fan
and other circulation fans provided in a longitudinal direction,
and securing a flow of hot air or cold air in a direction
approximately horizontal to the longitudinal direction of the
greenhouse and a flow of hot air or cold air covering a broad area
while mixing the hot air or the cold air exhausted from the exhaust
port with internal air staying in the vicinity of the exhaust port
by using the circulation fan and other circulation fans such that
the hot air or the cold air is evenly diffused in the entire
greenhouse" ([Claim 5]).
[0007] In the method using a mist cooling device, due to the
vaporization of water drops, the internal temperature of the
greenhouse becomes high. Therefore, ventilating means for
exchanging the internal air within the greenhouse is generally
used. For example, JP2014-198035A describes "a plant cultivation
greenhouse having a constitution in which an upper portion of a
greenhouse body (1) is covered with a transparent covering material
(2), the inside of the greenhouse body (1) is partitioned into two
chambers of upper and lower chambers consisting of an upper chamber
(21) on a ceiling side and a lower chamber (22) functioning as a
cultivation chamber by a partitioning material (6) which enables
air to flow up and down, an insect-proof net (3) is provided on a
lateral surface (11) of the lower chamber (22), the inside of the
upper chamber (21) is cooled with mist by a mist cooling device
(7), an exhaust fan (5) for exhausting the internal air within the
upper chamber (21) outside the greenhouse is provided, and the
internal air within the upper chamber (21) is forcedly exhausted by
the exhaust fan (5) such that the internal air within the lower
chamber (22) is aspirated into the upper chamber (21) and then the
external air is introduced into the lower chamber (22) through the
insect-proof net (3)" ([Claim 1]).
[0008] Meanwhile, an agricultural greenhouse is known which has a
double layer structure formed of two layers of film so as to
tolerate the low temperature during the winter season.
[0009] For example, JP2011-10590A describes "a thermal insulation
sheet which is disposed to totally cover a lateral surface of an
agricultural greenhouse, wherein at least two synthetic resin
sheets are fused in a horizontal direction at sites that separate
at a predetermined interval in a vertical direction such that a
plurality of portions of air flow paths is formed, and at each of
the sites where the synthetic resin sheets are fused, a plurality
of drainage portions communicating with each of the air flow paths
is provided in the horizontal direction at a necessary interval"
([Claim 1]). JP2011-10590A also describes an aspect in which the
synthetic resin sheet positioned on the outside is a
non-gas-permeable sheet while the synthetic resin sheet positioned
on the inside is a gas-permeable sheet in which a plurality of
micropores is formed ([Claim 3] and [Claim 4]).
[0010] Generally, the main material of the film for an agricultural
greenhouse is vinyl chloride, polyethylene, a polyethylene-vinyl
acetate copolymer, polyethylene terephthalate (PET), a
polyethylene-tetrafluoroethylene copolymer, or the like.
[0011] Because the agricultural greenhouse prepared from such a
material has low moisture permeability (water vapor permeability),
water vapor from the soil adheres to the internal surface of the
film and form water droplets. It is known that, as a result,
unfortunately, the transparency of the film deteriorates, and the
water droplets drip and damage the plants (for example, see
JP1989-320161A (JP-H01-320161A) and JP1994-279756A
(JP-H06-279756A)).
[0012] As a solution to the above problem, for example,
JP2009-039056A suggests "an agricultural laminated film comprising
a base film which is constituted by multiple layers including two
outermost layers containing a thermoplastic resin and an interlayer
containing a hydrophilic resin and a hydrophilic coating film which
is on the uppermost surface of at least one surface of the base
film, wherein a plurality of micropores is provided which is
obtained by performing a perforation process by using a needle
having thorn-like projections."
SUMMARY OF THE INVENTION
[0013] The inventors of the present invention conducted an
examination regarding the ventilation at the time of performing air
conditioning in a greenhouse. As a result, they revealed that, if
ventilation is performed, needless to say, the air conditioning
efficiency decreases, if air conditioning is performed without
ventilation so as to maintain the efficiency of air conditioning,
carbon dioxide (CO.sub.2) in the greenhouse is consumed due to the
photosynthesis of plants in the daytime, and consequently the
CO.sub.2 concentration necessary for the photosynthesis of plants
unfortunately becomes insufficient.
[0014] Furthermore, the inventors of the present invention revealed
that the aforementioned problem also occurs when plants are grown
without performing ventilation so as to prevent pest invasion.
[0015] Therefore, in a first aspect, the present invention aims to
provide a film for an agricultural greenhouse that can maintain a
CO.sub.2 concentration necessary for the photosynthesis of plants
even if ventilation is not performed, and an agricultural house
using the film (hereinafter, simply referred to as a "first
object").
[0016] Meanwhile, the inventors of the present invention conducted
an examination regarding a method for cooling the inside of a
greenhouse by using a spray device. As a result, they revealed
that, the agricultural greenhouse in which air conditioning
(cooling) is performed using mist as described in JP2014-198035A or
the like needs to be ventilated so as to decrease the internal
temperature of the greenhouse increased due to spraying, and
accordingly, a cumbersome operation of alternately performing mist
cooling and ventilation unfortunately needs to be carried out, and
there is an inflow of pests into the greenhouse due to
ventilation.
[0017] Therefore, in a second aspect, the present invention aims to
provide an agricultural greenhouse that does not require
ventilation means and can prevent the inflow of pests (hereinafter,
simply referred to as a "second object").
[0018] Furthermore, the inventors of the present invention
conducted an examination regarding the thermal insulation sheet
described in JP2011-10590A. As a result, they found out that, in a
case where a gas-permeable sheet in which micropores are formed is
used as the synthetic resin sheet (lining film) positioned on the
inside, the effect of preventing dew condensation occurring on the
inside of the sheet (inside of the agricultural greenhouse) due to
a temperature difference becomes insufficient, the light
transmittance is reduced, and hence the growth of plants or the
thermal insulation effect in the agricultural greenhouse is likely
to be impaired.
[0019] Therefore, in a third aspect, the present invention aims to
provide an agricultural greenhouse with a high light transmittance
in which the dew condensation occurring on the inside of a lining
film is inhibited (hereinafter, simply referred to as a "third
object).
[0020] In addition, the inventors of the present invention
conducted an examination regarding the films for an agricultural
greenhouse described in JP1989-320161A (JP-H01-320161A),
JP1994-279756A (JP-H06-279756A), JP2009-039056A, and the like known
in the related art. As a result, they revealed that, if
drip-proofness is improved, workability deteriorates in some cases,
and it is difficult to accomplish both the performances to a high
level.
[0021] Therefore, in a fourth aspect, the present invention aims to
provide a film for an agricultural greenhouse excellent in both
drip-proofness and workability (hereinafter, simply referred to as
a "fourth object").
[0022] In order to achieve the first object, the inventors of the
present invention conducted an intensive examination. As a result,
they found that, by using a cellulose film which contains a
cellulose acylate resin and has a moisture content represented by
an equilibrium moisture content of 4% to 8% at a temperature of
25.degree. C., a relative humidity of 80% and a thickness of 60 to
200 .mu.m, the CO.sub.2 concentration necessary for the
photosynthesis of plants can be maintained even if ventilation is
not performed. Based on what they have found, the inventors
accomplished the first aspect of the present invention.
[0023] That is, the inventors found that the first object can be
achieved by the following constitution.
[0024] [1] A film for an agricultural greenhouse that is a
cellulose film, comprising a cellulose acylate resin, in which the
film has an equilibrium moisture content of 4% to 8% at a
temperature of 25.degree. C. and a relative humidity of 80% and a
thickness of 60 to 200 .mu.m.
[0025] [2] The film for an agricultural greenhouse described in [1]
that has a light transmittance equal to or higher than 80%.
[0026] [3] The film for an agricultural greenhouse described in [1]
or [2] that has a water vapor permeability equal to or higher than
600 g/m.sup.2/24 h.
[0027] [4] The film for an agricultural greenhouse described in any
one of [1] to [3], in which a degree of acetyl group substitution
of the cellulose acylate resin is 2.5 to 3.0.
[0028] [5] An agricultural greenhouse comprising a frame and a
film, in which the film is the film for an agricultural greenhouse
described in any one of [1] to [4] and forms a space walled off
from the outside by being spread over the frame.
[0029] [6] The agricultural greenhouse described in [5] that does
not have a ventilation means for exhausting internal air within the
space to the outside.
[0030] Furthermore, in order to achieve the second object, the
inventors of the present invention conducted an intensive
examination. As a result, they found that, by constituting a
greenhouse by using a film which contains a cellulose acylate resin
and has a water vapor permeability equal to or higher than 600
g/m.sup.2/24 h and a thickness of 80 to 200 .mu.m, it is possible
to inhibit the inflow of pests without using ventilation means.
Based on what they have found, the inventors accomplished the
second aspect of the present invention.
[0031] That is, the inventors found that the second object can be
achieved by the following constitution.
[0032] [1] An agricultural greenhouse comprising a frame, a film,
and a spray device which sprays atomized water to the inside of a
space, in which the film is a cellulose film which forms the space
walled off from the outside by being spread over the frame,
contains a cellulose acylate resin, and has a water vapor
permeability equal to or higher than 600 g/m.sup.2/24 h and a
thickness of 80 to 200 .mu.m.
[0033] [2] The agricultural greenhouse described in [1], in which
the spray device is a mist cooling device which cools the space by
spraying atomized water into the space.
[0034] [3] The agricultural greenhouse described in [1] or [2] that
does not have ventilation means for exhausting internal air within
the space to the outside.
[0035] [4] The agricultural greenhouse described in any one of [1]
to [3], in which a degree of acetyl group substitution of the
cellulose acylate resin is 2.5 to 3.0.
[0036] In addition, in order to achieve the third object, the
inventors of the present invention conducted an intensive
examination. As a result, they found that, by using a cellulose
film, which contains a cellulose acylate resin and has a water
vapor permeability equal to or higher than 600 g/m.sup.2/24 h, as a
lining film and providing ventilation means for exchanging air
existing in an interspace between a lining film and a covering
film, it is possible to inhibit the dew condensation occurring on
the inside of the lining film and increase the light transmittance.
Based on what they have found, the inventors accomplished the third
aspect.
[0037] That is, the inventors found that the third object can be
achieve by the following constitution.
[0038] [1] An agricultural greenhouse comprising a covering film
which forms a space walled off from the outside, a lining film
which is provided on the inside of the covering film such that an
interspace is formed between the covering film and the lining film,
and ventilation means for exchanging at least a portion of the air
existing in the interspace with the external air, in which at least
a portion of the lining film is constituted with a cellulose film
which contains a cellulose acylate resin and has a water vapor
permeability equal to or higher than 600 g/m.sup.2/24 h.
[0039] [2] The agricultural greenhouse described in [1], in which
at least a portion of the covering film includes the ventilation
means, and the ventilation means is a film having a water vapor
permeability equal to or higher than 500 g/m.sup.2/24 h.
[0040] [3] The agricultural greenhouse described in [2], in which
the ventilation means is the cellulose film which contains a
cellulose acylate resin and has a water vapor permeability equal to
or higher than 600 g/m.sup.2/24 h.
[0041] [4] The agricultural greenhouse described in any one of [1]
to [3], in which a roof portion of the lining film is constituted
with the cellulose film.
[0042] Moreover, in order to achieve the fourth object, the
inventors of the present invention conducted an intensive
examination. As a result, they found that, by using a film which
contains a cellulose acylate resin and has a predetermined level of
water vapor permeability and modulus of elasticity, both
drip-proofness and workability can be improved. Based on what they
have found, the inventors accomplished the fourth aspect of the
present invention.
[0043] That is, the inventors found that the fourth object can be
achieved by the following constitution.
[0044] [1] A film for an agricultural greenhouse, comprising a
cellulose acylate resin, in which the film has a water vapor
permeability equal to or higher than 600 g/m.sup.2/24 h and a
modulus of elasticity of less than 3.0 GPa.
[0045] [2] The film for an agricultural greenhouse described in
[1], further comprising a plasticizer containing a polyether ester
and/or a polyether, in which a content of the plasticizer is 10 to
70 parts by mass with respect to 100 parts by mass of the cellulose
acylate resin.
[0046] [3] The film for an agricultural greenhouse described in [1]
or [2], in which a degree of acetyl group substitution of the
cellulose acylate resin is 2.5 to 3.0.
[0047] [4] The film for an agricultural greenhouse described in [2]
or [3], in which the plasticizer contains nolvether ester
renresented by the following Formula (A),
##STR00001## [0048] in Formula (A), R.sup.1 represents a divalent
aliphatic hydrocarbon group having 2 to 10 carbon atoms, R.sup.2
each independently represents a divalent aliphatic hydrocarbon
group having 2 to 6 carbon atoms, R.sup.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 each independently represents an
integer of 1 to 20, p represents an integer of 1 to 15, and a
plurality of R.sup.1's, R.sup.2's, and n's contained in a repeating
unit may be the same as or different to each other.
[0049] [5] The film for an agricultural greenhouse described in
[4], in which R3 in Formula (A) is an alkyl group having 1 to 20
carbon atoms.
[0050] [6] The film for an agricultural greenhouse described in [2]
or [3], in which the plasticizer contains a polyether represented
by the following Formula (B),
##STR00002## [0051] in Formula (B), R.sup.4 represents a divalent
aliphatic hydrocarbon group having 2 to 6 carbon atoms, R.sup.5 and
R.sup.6 each independently represents a hydrogen atom, an alkyl
group having 1 to 20 carbon atoms, an aryl group having 6 to 20
carbon atoms, an acyl group having 2 to 20 carbon atoms, a
(meth)acryloyl group, or a group represented by the following
Formula (b) obtained by polymerization of a (meth)acryloyl group, m
represents an integer of 1 to 20, and a plurality of R.sup.4's
contained in a repeating unit may be the same as or different to
each other,
[0051] ##STR00003## [0052] in Formula (b), * represents an oxygen
atom bonded to R.sup.5 or R.sup.6 in Formula (B), R.sup.7
represents a hydrogen atom or a methyl group, q represents an
integer of 1 to 10, and a plurality of R.sup.7's contained in a
repeating unit may be the same as or different to each other.
[0053] [7] The film for an agricultural greenhouse described in
[6], in which R.sup.5 in Formula (B) is an aryl group having 6 to
20 carbon atoms or a (meth)acryloyl group.
[0054] [8] The film for an agricultural greenhouse described in any
one of [1] to [7] that has a thickness of 60 .mu.m to 200
.mu.m.
[0055] According to the first aspect of the present invention, it
is possible to provide a film for an agricultural greenhouse that
can maintain a CO.sub.2 concentration necessary for the
photosynthesis of plants even if ventilation is not performed and
provide an agricultural greenhouse using the film.
[0056] According to the second aspect of the present invention, it
is possible to provide an agricultural greenhouse which does not
require ventilation means and can inhibit the inflow of pests.
[0057] According to the third aspect of the present invention, it
is possible to provide an agricultural greenhouse with a high light
transmittance in which the dew condensation occurring on the inside
of a lining film is inhibited.
[0058] According to the fourth aspect of the present invention, it
is possible to provide a film for an agricultural greenhouse
excellent in both drip-proofness and workability.
BRIEF DESCRIPTION OF THE DRAWINGS
[0059] FIG. 1 is a schematic perspective view showing an example of
the exterior of an agricultural greenhouse according to the first
and second aspects of the present invention.
[0060] FIG. 2 is a schematic cross-sectional view showing an
example of the interior of the agricultural greenhouse according to
the second aspect of the present invention.
[0061] FIG. 3 is a schematic perspective view showing an example of
the exterior of an agricultural greenhouse according to the third
aspect of the present invention except for a portion of the
agricultural greenhouse.
[0062] FIG. 4 is a schematic cross-sectional view showing an
example of the interior of the agricultural greenhouse according to
the third aspect.
[0063] FIG. 5 is a schematic cross-sectional view showing an
example of the interior of the agricultural greenhouse according to
the third aspect.
[0064] FIG. 6 is a schematic cross-sectional view showing an
example of the interior of the agricultural greenhouse according to
the third aspect.
[0065] FIG. 7 is a graph showing a change in carbon dioxide
concentration that occurs on the inside and the outside (external
air) of the greenhouse when a mist cooling device is moved in the
agricultural greenhouses prepared in Example 2-1 and Comparative
Example 2-1 of the second aspect of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0066] Hereinafter, the first to fourth aspects of the present
invention will be specifically described.
[0067] The constituents described below will be explained based on
representative embodiments of the present invention in some cases,
but the present invention is not limited to the embodiments.
[0068] In the present specification, a range of numerical values
described using "to" means a range which includes the numerical
values listed before and after "to" as a lower limit and an upper
limit.
[Film for an Agricultural Greenhouse (First Aspect)]
[0069] The film for an agricultural greenhouse according to the
first aspect of the present invention is a cellulose film which
contains a cellulose acylate resin and has an equilibrium moisture
content of 4% to 8% at a temperature of 25.degree. C., a relative
humidity of 80% and a thickness of 60 to 200 .mu.m.
[0070] Herein, the equilibrium moisture content at a temperature of
25.degree. C. and a relative humidity of 80% is a value obtained in
a manner in which a film as a measurement target (sample) is
humidified for 24 hours or longer in an environment with a
temperature of 25.degree. C. and a relative humidity of 80%, a
sample having a mass (500 mg) appropriate for the measurement is
then obtained from the film, the amount of moisture is measured
using a Karl Fischer moisture meter (AQ-2200, manufactured by
HIRANUMA SANGYO Co., LTD.), and the measured amount of moisture
(mg) is divided by the mass of the sample (500 mg).
[0071] As described above, in the first aspect of the present
invention, by using the cellulose film which contains a cellulose
acylate resin, has an equilibrium moisture content of 4% to 8% at a
temperature of 25.degree. C., a relative humidity of 80% and a
thickness of 60 to 200 .mu.m, a CO.sub.2 concentration necessary
for the photosynthesis of plants can be maintained even if
ventilation is not performed.
[0072] The reason why the aforementioned effects are brought about
is unclear, but is assumed to be as below according to the
inventors of the present invention.
[0073] Generally, it is known that a substance permeates into a
film by two kinds of methods, physical diffusion and carrier
transport. It is considered that, in the present invention, due to
the carrier transport by which the aforementioned cellulose film
takes in CO.sub.2 from the outside by using water as a medium, the
CO.sub.2 concentration can be maintained.
[0074] That is, because the film for an agricultural greenhouse
according to the first aspect of the present invention has an
affinity to water that is higher than that of a general film for an
agricultural greenhouse (for example, vinyl chloride or
polyethylene terephthalate (PET)), the aforementioned equilibrium
moisture content can be achieved. Herein, a decrease of strength of
the films, having a higher hydrophilicity (for example, polyvinyl
alcohol (PVA)), due to the water contained is not observed in the
film for an agricultural greenhouse according to the first aspect
of the present invention.
[0075] It is considered that, consequently, in a case where an
environment of high temperature and humidity is created in a
greenhouse, because the cellulose film contains water and CO.sub.2
outside the greenhouse is adsorbed onto or dissolves in water in
the cellulose film, CO.sub.2 can enter the greenhouse.
[0076] It is considered that the film for an agricultural
greenhouse according to the first aspect of the present invention
can bring in CO.sub.2 from the outside of the greenhouse as
described above. As a result of actually measuring a CO.sub.2
permeability of the aforementioned cellulose film, it was confirmed
that the CO.sub.2 permeability at a temperature of 25.degree. C.
and a relative humidity of 80% set to simulate a cultivation
environment in an agricultural greenhouse is equal to or higher
than 1.0.times.10.sup.-6 (cm.sup.3/(scm.sup.2cmHg)).
[0077] That is, the film for an agricultural greenhouse according
to the first aspect of the present invention can also be mentioned
as a film for an agricultural greenhouse which contains a cellulose
acylate resin and has a CO.sub.2 permeability equal to or higher
than 1.0.times.10.sup.-6 (cm.sup.3/(scm.sup.2cmHg)) at a
temperature of 25.degree. C. and a relative humidity of 80%.
[0078] Herein, the CO.sub.2 permeability of a general film is
measured under dry film conditions, that is, based on the
"differential pressure method" described in JIS K 6275-1.
[0079] Specifically, carbon dioxide is supplied to the surface
(supply side) of a sample under a pressure of 800 kPa, and the
pressure of the back surface (permeation side) is reduced down to 3
Pa by using a vacuum pump. Then, the vacuum pump is stopped, a
pressure change of the permeation side is recorded, and the
CO.sub.2 permeability is calculated by a time-delay method
according to JIS K 6275-1. The CO.sub.2 permeability is measured at
a temperature of 40.degree. C. within a sample evaluation area of
3.14 cm.sup.2.
[0080] In contrast, the CO.sub.2 permeability of the film for an
agricultural greenhouse according to the first aspect of the
present invention refers to a value measured under humid film
conditions, that is, a value obtained by measuring a CO.sub.2
permeability at a temperature of 25.degree. C. and a relative
humidity of 80% set to simulate a cultivation environment in an
agricultural greenhouse by the following method.
[0081] First, by using frameworks made of stainless steel, a
skeleton of 25 cm.times.33 cm.times.33 cm was assembled, and each
film was bonded to all the surfaces (6 surfaces) thereof, thereby
preparing a small-sized greenhouse test sample.
[0082] Then, the greenhouse test sample was humidified for 24 hours
or longer in an environment with a temperature of 25.degree. C. and
a relative humidity of 80%, a CO2 concentration meter (TR-76UI,
manufactured by T&D Corporation.) was then installed on the
inside of the sample, CO.sub.2 gas was blown into the sample until
the concentration thereof reached 10,000 ppm, and the inside of the
greenhouse test sample was sealed using a pressure-sensitive
adhesive tape.
[0083] Thereafter, the sample was installed in an environment with
a temperature of 25.degree. C. and a relative humidity of 80%, the
surface (film) of the greenhouse test sample was placed in running
water such that the sample was wet all the time, and the trend in
CO.sub.2 gas concentration in the environment was recorded for 24
hours.
[0084] From the results obtained by recording the decrease in the
internal CO.sub.2 gas concentration for 24 hours, a rate of
decrease in the CO.sub.2 gas concentration was determined and
compared with fitted CO.sub.2 gas concentration obtained using
theoretical values, thereby obtaining a CO.sub.2 permeability
coefficient under humid film conditions (a temperature of
25.degree. C. and a relative humidity of 80%).
[0085] The fitted CO.sub.2 gas concentration was obtained by
calculating T representing the amount of CO.sub.2 permeating per
unit time (that is, CO.sub.2 permeability) by the following
equation and plotting a theoretical change of CO.sub.2
concentration with respect to the time elapsed.
[0086] For the CO.sub.2 concentration, on the assumption that gas
may move for 1 second under the initial pressure difference
conditions, the values of the CO.sub.2 permeability coefficient was
fitted to the actual measured value.
T(CO.sub.2 permeability)=(CO.sub.2 permeability
coefficient.times.surface area of film.times.pressure
difference)/film thickness
<Cellulose Acylate Resin>
[0087] The cellulose acylate resin contained in the film for an
agricultural greenhouse according to the first aspect of the
present invention is not particularly limited, and it is possible
to use those known in the related art such as a cellulose acylate
resin containing an aliphatic acyl group having 2 to 22 carbon
atoms (for example, an acetyl group, a propionyl group, a butyryl
group, or a pentanoyl group) and a cellulose acylate resin
containing at least one kind of an unsubstituted aromatic acyl
group.
[0088] From the viewpoint of retaining the water vapor permeability
which will be described later, the content of the cellulose acylate
resin is preferably 60% to 90% by mass and more preferably 65% to
80% by mass, with respect to the total mass of the cellulose
film.
[0089] Examples of raw material cellulose of the cellulose acylate
resin include cotton linter, Amharic hemp, wood pulp (hardwood pulp
and softwood pulp), and the like. One kind of these may be used
singly, or two or more kinds thereof may be used in
combination.
[0090] Among these, as the raw material cellulose, either or both
cotton linter and wood pulp are preferable.
[0091] It is preferable that either or both cotton linter and wood
pulp contain ct-cellulose in a proportion equal to or higher than
80%.
[0092] Furthermore, in either or both cotton linter and wood pulp,
mannose/xylose preferably equals 0.35/1 to 3.0/1 (molar ratio), and
the total content thereof is preferably 0.01 to 5 mol %.
[0093] In a case where the cotton linter and the wood pulp are used
in combination, a mixing ratio therebetween is preferably 5/95 to
95/5.
[0094] The cellulose acylate constituting the cellulose acylate
resin is a carboxylic acid ester of cellulose and preferably, for
example, a lower carboxylic acid ester of the cellulose.
[0095] Specific examples of the cellulose acylate include cellulose
acetate, cellulose acetate propionate, cellulose acetate butyrate,
cellulose acetate stearate, cellulose acetate benzoate, and the
like.
[0096] Among these, cellulose acetate is preferable, and
specifically, triacetyl cellulose (TAC) is more preferable.
[0097] It is preferable that the cellulose acylate is manufactured
by combining any of an activation step (pretreatment step), an
acylation step (in a case of acetyl, an acetylation step), a
maturing step, a precipitation step, a purification step, a drying
step, and a grinding step.
[0098] The raw material cotton of the cellulose acylate or the
synthesis method thereof is described in pages 7 to 12 of the
technical report from Japanese Institute of Invention and
Innovation (open technique No. 2001-1745, published on Mar. 15,
2001, Japanese Institute of Inventions and Innovation).
[0099] The viscosity average polymerization degree (DP) of the
cellulose acylate is preferably 200 to 700.
[0100] Furthermore, the ratio (Mw/Mn) of weight-average molecular
weight (Mw)/number-average molecular weight (Mn) of the cellulose
acylate is preferably 1.0 to 5.0, more preferably 1.0 to 4.0, and
even more preferably 1.5 to 3.0.
[0101] Herein, the viscosity average polymerization degree refers
to the average molecular weight determined by a viscosity method
(ASTM D2857), and the weight-average molecular weight and the
number-average molecular weight each refer to a molecular weight
measured by a gel permeation chromatography (GPC) method.
[0102] It is preferable that, in the cellulose acylate, the amount
of residual acetic acid or the amount of residual carboxylic acid
having 3 to 22 carbon atoms is equal to or less than 0.5% by
mass.
[0103] It is preferable that the cellulose acylate contains at
least one kind of an alkali metal and/or an alkaline earth metal in
an amount of 1 ppb to 10,000 ppm.
[0104] It is preferable that the amount of the cellulose acylate
extracted using acetone at a temperature of 25.degree. C. is equal
to or less than 15% by mass.
[0105] It is preferable that the cellulose acylate contains an acid
having an acid dissociation constant of 1.93 to 4.5, a partially
esterified substance, or a salt of these.
[0106] It is preferable that the moisture content of the cellulose
acylate is equal to or less than 2% by mass.
[0107] Furthermore, it is preferable that the yellowness index of
the cellulose acylate is 0.1 to 10.
[0108] It is preferable that the haze of the cellulose acylate is
0.05% to 5%.
[0109] Furthermore, it is preferable that the light transmittance
of the cellulose acylate is equal to or higher than 80% and more
preferably equal to or higher than 85%.
[0110] It is preferable that Tg of the cellulose acylate is
80.degree. C. to 200.degree. C.
[0111] Furthermore, it is preferable that the crystallization
heating value of the cellulose acylate is 2 to 20 J/g.
[0112] In the first aspect of the present invention, it is
preferable that a degree of substitution of a hydroxyl group on the
cellulose in the cellulose acylate satisfies the following
Expressions (1) and (2)
2.0.ltoreq.SA+SB.ltoreq.3.0 Expression (1)
0.ltoreq.SA.ltoreq.3.0 Expression (2)
[0113] In the expressions, "SA" represents a degree of substitution
of an acetyl group substituting a hydrogen atom of a hydroxyl group
on the cellulose, and "SB" represents a degree of substitution of
an acyl group other than the acetyl group that substitutes a
hydrogen atom of a hydroxyl group on the cellulose.
[0114] Expression (2) is preferably represented by the following
Expression (3) because then the workability of the obtained film
for an agricultural greenhouse according to the first aspect of the
present invention is further improved. Expression (2) is more
preferably represented by the following Expression (4), because
then the equilibrium moisture content increases, and the CO.sub.2
concentration can be kept to be approximately the same as the
external CO.sub.2 concentration of the greenhouse.
2.0.ltoreq.SA.ltoreq.3.0 Expression (3)
2.2.ltoreq.SA.ltoreq.2.6 Expression (4)
<Additives>
[0115] Depending on the usage environment, the film for an
agricultural greenhouse according to the first aspect of the
present invention may contain additives such as a plasticizer, a
matting agent, a deterioration preventing agent, and an ultraviolet
absorbent.
[0116] Specific examples of the plasticizer suitably include an
ester-based plasticizer containing a polyether ester represented by
the following Formula (A) and an ether-based plasticizer containing
a polyether represented by the following Formula (B).
##STR00004##
##STR00005##
[0117] In Formula (A), R.sup.1 represents a divalent aliphatic
hydrocarbon group having 2 to 10 carbon atoms, R.sup.2 each
independently represents a divalent aliphatic hydrocarbon group
having 2 to 6 carbon atoms, R.sup.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 each independently represents an integer of 1 to
20, p represents an integer of 1 to 15, and a plurality of
R.sup.1's, R.sup.2's, and n's contained in a repeating unit may be
the same as or different to each other.
[0118] In Formula (B), R.sup.4 represents a divalent aliphatic
hydrocarbon group having 2 to 6 carbon atoms, R.sup.5 and R.sup.6
each independently represents a hydrogen atom, an alkyl group
having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon
atoms, an acyl group having 2 to 20 carbon atoms, a (meth)acryloyl
group, or a group represented by the following Formula (b) obtained
by polymerization of a (meth)acryloyl group, m represents an
integer of 1 to 20, and a plurality of R.sup.4's contained in a
repeating unit may be the same as or different to each other.
[0119] In the present specification, a "(meth)acryloyl group" means
an acryloyl group (CH.sub.2=CHCO--) or a methacryloyl group
(CH.sub.2=C(CH.sub.3)CO--).
##STR00006##
[0120] In Formula (b), * represents an oxygen atom bonded to
R.sup.5 or R.sup.6 in Formula (B), R.sup.7 represents a hydrogen
atom or a methyl group, q represents an integer of 1 to 10, and a
plurality of R.sup.7's contained in a repeating unit may be the
same as or different to each other.
[0121] In the first aspect of the present invention, in a case
where the film for an agricultural greenhouse contains a
plasticizer, the content of the plasticizer, with respect to 100
parts by mass of the cellulose acylate resin, is preferably 10 to
70 parts by mass, more preferably 20 to 60 parts by mass, even more
preferably 30 to 60 parts by mass, and particularly preferably 40
to 60 parts by mass.
[0122] As the matting agent, any one of organic and inorganic
particles can be used.
[0123] Specific examples of the deterioration preventing agent
include a hindered amine-based light stabilizer, an antioxidant, a
peroxide decomposer, a radical inhibitor, a metal deactivator, an
acid acceptor, an amine, and the like.
[0124] The ultraviolet absorbent can absorb ultraviolet rays, and
known ultraviolet absorbents can be used. Examples thereof suitably
include ultraviolet absorbents based on benzotriazole or
hydroxyphenyltriazine.
[0125] In a case where these additives are added, it is preferable
to incorporate the additives into a cellulose acylate solution
(dope) which will be described later.
[0126] The equilibrium moisture content of the film for an
agricultural greenhouse according to the first aspect of the
present invention is 4% to 8%. It is preferable that the
equilibrium moisture content is 5% to 8% because then the CO.sub.2
concentration can be easily maintained.
[0127] The thickness of the film for an agricultural greenhouse
according to the first aspect of the present invention is 60 .mu.m
to 200 .mu.m. The thickness is preferably 80 .mu.m to 150 .mu.m and
more preferably 80 .mu.m to 120 .mu.m, because then the workability
can be improved.
[0128] The film for an agricultural greenhouse may have a single
layered structure or a laminated structure, but it is preferable
that the film has a single layered structure.
[0129] The light transmittance of the film for an agricultural
greenhouse according to the first aspect of the present invention
is preferably equal to or higher than 80%, more preferably equal to
or higher than 85%, and even more preferably equal to or higher
than 90%, because then the photosynthesis of plants in the
greenhouse can be accelerated, and the internal temperature of the
greenhouse can be suitably maintained.
[0130] Herein, the light transmittance refers to a transmittance
measured using a spectrophotometer (manufactured by Jasco
Engineering and Sales, Inc.: V-560) and represented by the
calculated average regarding a wavelength region (400 to 700 nm)
effective for photosynthesis.
[0131] The water vapor permeability of the film for an agricultural
greenhouse according to the first aspect of the present invention
is preferably equal to or higher than 600 g/m.sup.2/24 h, more
preferably equal to or higher than 800 g/m.sup.2/24 h, and even
more preferably equal to or higher than 1,000 g/m.sup.2/24 h,
because then the occurrence of dew condensation in the agricultural
greenhouse can be effectively inhibited, the internal relative
humidity of the greenhouse in the mist can be reduced, and the mist
cooling effect can be maintained.
[0132] Herein, the water vapor permeability refers to the amount of
water vapor (g/m.sup.2/24 h), which passes through the film for 24
hours under the conditions of a temperature of 40.degree. C. and a
relative humidity of 90%, measured according to the technique
described in JIS Z 0208:1976 "Testing methods for determination of
the water vapor permeability (cup method) of moisture-proof packing
materials".
<Method for Manufacturing Film for an Agricultural
Greenhouse>
[0133] The method for manufacturing the film for an agricultural
greenhouse according to the first aspect of the present invention
is not particularly limited. Examples of the method include a
solution film-forming method in which a dope (cellulose acylate
solution) obtained by dissolving cellulose acylate in an organic
solvent is cast from a casting die onto a support formed of an
endless belt or a drum (hereinafter, these will be collectively
simply referred to as a "support") rotating in a casing, and the
dope is peeled from the support and dried so as to form a film.
(Organic Solvent)
[0134] Examples of the organic solvent dissolving the cellulose
acylate include a hydrocarbon-based solvent such as benzene or
toluene; a halogenated hydrocarbon-based solvent such as methylene
chloride or chlorobenzene; an alcohol-based solvent such as
methanol, ethanol, or diethylene glycol; a ketone-based solvent
such as acetone; an ester-based solvent such as methyl acetate,
ethyl acetate, or propyl acetate; an ether-based solvent such as
tetrahydrofuran or methyl cellosolve; and the like. One kind of
these may be used singly, or two or more kinds thereof may be used
in combination.
[0135] Among these, a halogenated hydrocarbon-based solvent having
1 to 7 carbon atoms is preferably used, and methylene chloride is
more preferably used.
[0136] From the viewpoint of the solubility of the cellulose
acylate, the property of peeling the dope from the support, the
mechanical strength of the film, and the like, it is preferable to
use an alcohol having 1 to 5 carbon atoms in combination with
methylene chloride. The content of the alcohol is preferably 2% to
25% by mass and more preferably 5% to 20% by mass with respect to
the total amount of the solvent. Specific examples of the alcohol
include methanol, ethanol, n-propanol, isopropanol, n-butanol, and
the like. Among these, methanol, ethanol, n-butanol, or a mixture
of these is preferably used.
(Preparation of Cellulose Acylate Solution)
[0137] The method for preparing a cellulose acylate solution is
preferably a preparation method in which, first, cellulose acylate
and an organic solvent are mixed together, the cellulose acylate is
dissolved at -10.degree. C. to 55.degree. C., and the mixture of
the dissolved portion of the cellulose acylate, an undissolved
portion of the cellulose acylate, and the organic solvent is heated
to 0.degree. C. to 97.degree. C. such that the cellulose acylate
completely dissolves in the solvent.
[0138] Herein, if necessary, the cellulose acylate solution to be
prepared may be concentrated, and the concentration of the
cellulose acylate is preferably 5% to 40% by mass. Furthermore, the
viscosity of the cellulose acylate solution measured at 40.degree.
C. is preferably 10 to 3,000 Pas.
[0139] When the cellulose acylate and the organic solvent are mixed
together, 90% by mass or more of the cellulose acylate is
preferably used in the form of particles having a size of 0.1 to 4
mm.
[0140] It is preferable that the cellulose acylate solution is
filtered at a temperature of 0.degree. C. to 200.degree. C. before
casting.
[0141] Herein, the average pore size of the filter is preferably
equal to or less than 100 .mu.m, and the flow rate for the
filtration is preferably equal to or higher than 50 L/hr.
(Casting)
[0142] In the step of casting the cellulose acylate solution, the
temperature of the solution is preferably -10.degree. C. to
57.degree. C. During this step, the temperature is preferably kept
at -10.degree. C. to 57.degree. C.
[0143] The surface temperature of the support onto which the
cellulose acylate solution is cast is preferably -20.degree. C. to
40.degree. C.
(Peeling)
[0144] During peeling following casting, the temperature of the
drying air at the time of peeling is preferably 20.degree. C. to
250.degree. C. Furthermore, the film for an agricultural greenhouse
that has not yet been dried at the time of drying is held by a
tenter.
[0145] It is preferable that the film for an agricultural
greenhouse prepared by the solution film-forming method described
above is stretched 0.5% to 300% during uniaxial casting or after
casting. Furthermore, the rate at the time of casting is preferably
1 to 200 m/min.
[0146] It is preferable that the film for an agricultural
greenhouse is wound such that the lengths of the film in a
longitudinal direction and a width direction become equal to or
greater than 100 m and equal to or greater than 60 cm
respectively.
[0147] In the present invention, the aforementioned method for
manufacturing a cellulose acylate film is not particularly limited,
and known methods other than the aforementioned method can be
appropriately adopted. For example, it is possible to appropriately
adopt the method described in pages 12 to 30 of the technical
report from Japanese Institute of Invention and Innovation (open
technique No. 2001-1745, published on Mar. 15, 2001, Japanese
Institute of Inventions and Innovation).
[Agricultural Greenhouse (First Aspect)]
[0148] The agricultural greenhouse according to the first aspect of
the present invention is an agricultural greenhouse having a frame
and a film, in which a space walled off from the outside is formed
by spreading the film over the frame.
[0149] FIG. 1 is a schematic perspective view showing an example of
the exterior of the agricultural greenhouse according to the first
aspect of the present invention.
[0150] As shown in FIG. 1, an agricultural greenhouse 10 has a film
1 spread over a frame 2.
[0151] Furthermore, as shown in FIG. 1, the entire surface of the
agricultural greenhouse 10 is covered with the film 1 spread over
the frame 2, and the agricultural greenhouse 10 does not have the
exhaust fan illustrated in FIG. 4 or the like of JP2010-17093A.
[0152] Hereinafter, the frame and the film constituting the
agricultural greenhouse according to the first aspect of the
present invention will be specifically described.
[Frame]
[0153] The frame that the agricultural greenhouse according to the
first aspect of the present invention has is not particularly
limited, and it is possible to use frameworks (for example, steel
or steel pipes) used in a plastic greenhouse and the like known in
the related art.
[Film]
[0154] The film that the agricultural greenhouse according to the
first aspect of the present invention has is a film that is spread
over the aforementioned frame and is the aforementioned film for an
agricultural greenhouse according to the first aspect of the
present invention.
[0155] The agricultural greenhouse according to the first aspect of
the present invention has the aforementioned film for an
agricultural greenhouse according to the first aspect of the
present invention. Therefore, the agricultural greenhouse can
maintain a CO.sub.2 concentration necessary for the photosynthesis
of plants even if ventilation is not performed.
[0156] Consequently, the agricultural greenhouse according to the
first aspect of the present invention does not need to be provided
with active ventilation means (for example, a ventilation fan
provided on the ceiling or the lateral surface of a greenhouse),
has an excellent air conditioning efficiency, and has an effect of
being able to inhibit the inflow of pests.
[0157] In the present invention, although the ventilation means
does not include an entrance for the workers working in the
agricultural greenhouse, it is preferable that the entrance is made
into a double door such that the external air does not directly
flow into the internal space of the greenhouse.
[Agricultural Greenhouse (Second Aspect)]
[0158] The agricultural greenhouse according to the second aspect
of the present invention is an agricultural greenhouse having a
frame and a film, in which a space walled off from the outside is
formed by spreading the film over the frame.
[0159] The film is a cellulose film which contains a cellulose
acylate resin and has a water vapor permeability equal to or higher
than 600 g/m.sup.2/24 h and a thickness of 80 to 200 .mu.m.
[0160] The agricultural greenhouse according to the second aspect
of the present invention also has a spray device that sprays
atomized water into the space.
[0161] FIG. 1 is a schematic perspective view showing an example of
the exterior of the agricultural greenhouse according to the second
aspect of the present invention. FIG. 2 is a schematic
cross-sectional view showing an example of the interior of the
agricultural greenhouse according to the second aspect of the
present invention.
[0162] As shown in FIGS. 1 and 2, the agricultural greenhouse 10
has the film 1 spread over the frame 2, a spray device 3 spraying
atomized water into the space of the greenhouse, and a water supply
tank 4.
[0163] Furthermore, as shown in FIGS. 1 and 2, the entire surface
of the agricultural greenhouse 10 is covered with the film 1 spread
over the frame 2, and the agricultural greenhouse 10 does not have
the intake fan or the exhaust fan illustrated in FIG. 1 or the like
of JP2014-198035A.
[0164] The agricultural greenhouse according to the second aspect
of the present invention is constituted as above. Particularly, the
agricultural greenhouse is constituted with the film which contains
a cellulose acylate resin and has a water vapor permeability equal
to or greater than 600 g/m.sup.2/24 h and a thickness of 80 to 200
.mu.m. Therefore, even if the greenhouse is cooled using the spray
device, ventilation means is not required, and the inflow of pests
can be inhibited.
[0165] The details of the reason why the aforementioned effects are
brought about are unclear. Presumably, by setting the water vapor
permeability and the thickness of the film to be within the
aforementioned range of numerical values, at least a portion of the
water sprayed from the spray device may slowly pass through the
film toward the outside, the internal humidity of the agricultural
greenhouse may be decreased, and hence the aforementioned effects
may be obtained.
[0166] Hereinafter, the frame, the film, and the spray device
constituting the agricultural greenhouse according to the second
aspect of the present invention will be specifically described.
[Frame]
[0167] The frame that the agricultural greenhouse according to the
second aspect of the present invention has is not particularly
limited, and it is possible to use frameworks (for example, steel
or steel pipes) used in a plastic greenhouse and the like known in
the related art.
[Film]
[0168] The film that the agricultural greenhouse according to the
second aspect of the present invention has (hereinafter, referred
to as a "film for an agricultural greenhouse according to the
second aspect" as well) is a film spread over the aforementioned
frame. The film is a cellulose film which contains a cellulose
acylate resin and has a water vapor permeability equal to or higher
than 600 g/m.sup.2/24 h and a thickness of 80 to 200 .mu.m.
[0169] Herein, the water vapor permeability has the same definition
as the water vapor permeability described for the film for an
agricultural greenhouse according to the first aspect of the
present invention.
<Cellulose Acylate Resin>
[0170] The cellulose acylate resin contained in the film for an
agricultural greenhouse according to the second aspect is not
particularly limited, and examples thereof are the same as the
examples of the cellulose acylate resins contained in the film for
an agricultural greenhouse according to the first aspect of the
present invention.
<Additives>
[0171] Depending on the usage environment, the film for an
agricultural greenhouse according to the second aspect may contain
additives such as a plasticizer, a matting agent, a deterioration
preventing agent, and an ultraviolet absorbent.
[0172] Examples of the additives are the same as the examples of
the additives described above for the film for an agricultural
greenhouse according to the first aspect of the present
invention.
[0173] The thickness of the film for an agricultural greenhouse
according to the second aspect is 80 .mu.m to 200 .mu.m. The
thickness is preferably 80 .mu.m to 150 .mu.m and more preferably
80 .mu.m to 120 .mu.m, because then the workability can be further
improved.
[0174] The film for an agricultural greenhouse according to the
second aspect may have a single layered structure or a laminated
structure, but it is preferable that the film has a single layered
structure.
<Method for Manufacturing Film for Agricultural
Greenhouse>
[0175] The method for manufacturing the film for an agricultural
greenhouse according to the second aspect is not particularly
limited, and examples of the method are the same as the examples of
the method described above for the film for an agricultural
greenhouse according to the first aspect of the present
invention.
[Spray Device]
[0176] The spray device that the film for an agricultural
greenhouse according to the second aspect has is a device spraying
atomized water into the space of the greenhouse.
[0177] As will be described later, the spray device is preferably a
mist cooling device that cools the space by spraying atomized water
into the space of the greenhouse. Examples of the spray device
include the mist cooling device, which will be described later, a
device used for supplying water to the plants in a greenhouse, and
the like.
<Mist Cooling Device>
[0178] The mist cooling device is also referred to as a mist
cooling fan, and for example, it is possible to use a known device
such as a mist fan, a mist cooler, or the like.
[0179] Specific examples of the mist cooling device include the
"mist cooling device controlling the growth of crops that is
constituted with a fan sending air and spray means for sending mist
to the fan" described in JP2010-068740A, the "device which can
spray water into a space by using an air atomizing-type nozzle
atomizing a liquid by using pressurized air" described in
JP2000-157068A, and the like.
[0180] In FIG. 2, the water supply tank 4 is installed in the
agricultural greenhouse. However, in the present invention, only
the means for spraying atomized water into the space in the
greenhouse (for example, a blast fan or a nozzle) may be installed
in the agricultural greenhouse.
<Spray Amount>
[0181] In the second aspect of the present invention, the spray
amount of the spray device is preferably 5 to 30 g/m.sup.2min and
more preferably 10 to 20 g/m.sup.2min, because then a sufficient
cooling effect can be obtained even in the daytime during the
summer season, and the occurrence of dew condensation can be
further inhibited.
[0182] The agricultural greenhouse according to the second aspect
of the present invention has the aforementioned film for an
agricultural greenhouse according to the second aspect. Therefore,
the agricultural greenhouse does not require ventilation means and
can inhibit the inflow of pests.
[0183] Accordingly, the agricultural greenhouse according to the
second aspect of the present invention does not need to be provided
with active ventilation means (for example, a ventilation fan
provided on the ceiling or the lateral surface of a greenhouse).
However, it is preferable that the agricultural greenhouse does not
have ventilation means, because then the inflow of pests can
further be inhibited, and the environment necessary for the growth
of plants can be easily created. In the present invention, although
the ventilation means does not include an entrance for the workers
working in the agricultural greenhouse, it is preferable that the
entrance is made into a double door such that the external air does
not directly flow into the greenhouse.
[0184] The agricultural greenhouse according to the second aspect
of the present invention has the aforementioned film for an
agricultural greenhouse. Consequently, as will be shown in FIG. 7
which will be described later, the carbon dioxide concentration in
the greenhouse can be kept to be the same as the carbon dioxide
concentration of the external air. Therefore, it is not necessary
to perform an operation of blowing carbon dioxide necessary for the
photosynthesis of plants into the greenhouse from the outside.
[Agricultural Greenhouse (Third Aspect)]
[0185] The agricultural greenhouse according to the third aspect of
the present invention has a covering film which forms a space
walled off from the outside, a lining film which is provided on the
inside of the covering film such that an interspace is formed
between the covering film and the lining film, and ventilation
means for exchanging at least a portion of the air existing in the
interspace with the external air. In the present invention, as will
be described later, a portion of the covering film may include the
ventilation means, or the entirety of the covering film may include
the ventilation means.
[0186] At least a portion of the lining film in the agricultural
greenhouse according to the third aspect of the present invention
is a film constituted with a cellulose film which contains a
cellulose acylate resin and has a water vapor permeability equal to
or higher than 600 g/m.sup.2/24 h.
[0187] FIG. 3 is a schematic perspective view showing an example of
the exterior of the agricultural greenhouse according to the third
aspect of the present invention except for a portion of the
agricultural greenhouse. FIGS. 4 to 6 are schematic cross-sectional
views showing an example of the interior of the agricultural
greenhouse of the present invention.
[0188] As shown in FIGS. 3 to 6, an agricultural greenhouse 20 has
a covering film 11 and a lining film 12 (reference 12a: roof
portion, reference 12b: wall surface portion).
[0189] As shown in FIG. 3, the covering film 11 preferably has an
aspect in which the film is spread over a frame 13.
[0190] Although the agricultural greenhouse 20 shown in FIGS. 3 to
5 shows an aspect in which at least a portion of the covering film
11 functions as ventilation means as well, as shown in FIG. 6, a
ventilation fan 14 constituted as a member separated from the
covering film 11 may be provided.
[0191] The agricultural greenhouse according to the third aspect of
the present invention is constituted as above. Particularly, the
agricultural greenhouse uses the cellulose film, which contains a
cellulose acylate resin and has a water vapor permeability equal to
or higher than 600 g/m.sup.2/24 h, as the lining film and is
provided with the ventilation means for exchanging the air existing
in the interspace between the lining film and the covering film.
Therefore, the dew condensation occurring on the inside of the
lining film can be inhibited, and the light transmittance of the
agricultural greenhouse can be increased.
[0192] The details of the reason why the aforementioned effects are
brought about are unclear, but are assumed to be as below according
to the inventors of the present invention.
[0193] First, in the gas-permeable sheet described in JP2011-10590A
in which micropores are formed, the water vapor permeability is
improved due to the existence of the pores, and accordingly, the
effect of reducing the internal humidity of an agricultural
greenhouse is obtained. However, presumably, once the dew
condensation occurs, the pores may be clogged due to the dew
condensation, and hence the moisture permeability may be impaired.
Furthermore, presumably, due to the dew condensation or the
existence of the pores, the light transmittance may be reduced.
[0194] In contrast, in the third aspect of the present invention,
the cellulose film contains the cellulose acylate resin, and hence
the hydrophilicity is improved, and the hygroscopicity of the
lining film is enhanced. Furthermore, because the water vapor
permeability is equal to or higher than 600 g/m.sup.2/24 h, the
in-plane distribution of the water vapor permeability within the
lining film substantially disappears. As a result, the occurrence
of dew condensation can be completely inhibited, or the dew
condensation that has occurred can be efficiently resolved.
Presumably, for the above reason, the dew condensation occurring on
the inside of the lining film can be inhibited, and the light
transmittance of the agricultural greenhouse can be increased.
[0195] Hereinafter, the lining film, the covering film, and the
ventilation means constituting the agricultural greenhouse
according to the third aspect of the present invention will be
specifically described.
[Lining Film]
[0196] The lining film that the agricultural greenhouse according
to the third aspect of the present invention has is a film which is
provided on the inside of the covering film, which will be
described later, such that an interspace is formed between the
covering film and the lining film. The lining film is a film in
which at least a portion thereof is constituted with a cellulose
film which contains a cellulose acylate resin and has a water vapor
permeability equal to or higher than 600 g/m.sup.2/24 h.
[0197] Herein, the water vapor permeability has the same definition
as the water vapor permeability described above for the film for an
agricultural greenhouse according to the first aspect of the
present invention.
<Cellulose Acylate Resin>
[0198] The cellulose acylate resin contained in the cellulose film
is not particularly limited, and examples thereof are the same as
the examples of the cellulose acylate resin contained in the film
for an agricultural greenhouse according to the first aspect of the
present invention.
<Additives>
[0199] Depending on the usage environment, the cellulose film may
contain additives such as a plasticizer, a matting agent, a
deterioration preventing agent, and an ultraviolet absorbent.
[0200] Examples of these additives are the same as the examples of
the additives described above for the film for an agricultural
greenhouse according to the first aspect of the present
invention.
<Method for Manufacturing Cellulose Film>
[0201] The method for manufacturing the cellulose film is not
particularly limited, and examples of the method are the same as
the examples of the method described above for the film for an
agricultural greenhouse according to the first aspect of the
present invention.
[0202] In the third aspect of the present invention, it is
preferable that the roof portion of the lining film is constituted
with the aforementioned cellulose film, because the growth failure
of plants that occurs due to the dripping of dews can then be
prevented. It is more preferable that both the roof portion and the
wall surface portion of the lining film are constituted with the
cellulose film.
[0203] Herein, the roof portion of the lining film refers to the
upper portion of the space where plants grow, that is, the portion
positioned in a direction perpendicular to the soil or the like in
which plants are placed. The roof portion refers to the portion
indicated by the reference 12a in FIGS. 3 to 6.
[0204] The wall surface portion of the lining film refers to the
lateral portion of the space in which plants grow, that is, the
portion positioned in a direction horizontal to the soil or the
like in which plants are placed. The wall surface portion refers to
the portion indicated by the reference 12b in FIGS. 3 to 6.
[0205] The thickness of the lining film is preferably 60 .mu.m to
200 .mu.m, more preferably 80 .mu.m to 150 .mu.m, and even more
preferably 80 .mu.m to 120 .mu.m, because then the workability can
be improved.
[0206] The lining film may have a single layered structure or a
laminated structure, but it is preferable that the film has a
single layered structure.
[Covering Film]
[0207] The covering film that the agricultural greenhouse according
to the third aspect of the present invention has is a film forming
a space walled off from the outside.
[0208] The covering film is not particularly limited, and examples
of the constituent material thereof include polyethylene
terephthalate, polybutylene terephthalate, polycarbonate,
polyethylene, an acrylic resin, polyvinyl chloride, polyvinyl
alcohol, a cellulose acylate resin, a fluorine-containing resin,
and the like.
[0209] In the third aspect of the present invention, it is
preferable that at least a portion of the covering film includes
ventilation means which will be described later, and that the
ventilation means is a film having a water vapor permeability equal
to or higher than 500 g/m.sup.2/24 h, because then the moisture
permeability can be retained, and the occurrence of dew
condensation can be further inhibited.
[0210] Herein, "at least a portion of the covering film includes
ventilation means which will be described later" means that at
least a portion of the covering film has a function of exchanging
at least a portion of the air existing in the interspace between
the covering film and the lining film with the external air. In
this case, the agricultural greenhouse may not have ventilation
means (for example, the ventilation fan 14 shown in FIG. 6)
constituted as a member separated from the covering film.
[0211] Furthermore, "the entirety of the covering film includes the
ventilation means which will be described later" means that the
entirety of the covering film has a function of exchanging at least
a portion of the air existing in the interspace between the
covering film and the lining film with the external air. In this
case, the covering film and the ventilation means may be
constituted with the same member.
[0212] Examples of the aforementioned film having a water vapor
permeability equal to or higher than 500 g/m.sup.2/24 h include the
agricultural film described in JP2007-089493A, the cellulose film
described above as the lining film, and the like.
[0213] Among these, the cellulose film which contains a cellulose
acylate resin and has a water vapor permeability equal to or higher
than 600 g/m.sup.2/24 h is preferable, because water droplets
resulting from rain does not infiltrate into such film, and the
light transmittance can be further increased.
[Ventilation Means]
[0214] The ventilation means that the agricultural greenhouse
according to the third aspect of the present invention has is means
for exchanging at least a portion of the air existing in the
interspace between the aforementioned covering film and the lining
film with the external air.
[0215] As described above, the ventilation means has an aspect in
which the ventilation portion is provided in at least a portion of
the covering film. That is, examples of the ventilation means
include a film having a water vapor permeability equal to or higher
than 500 g/m.sup.2/24 h, a member constituted as a unit (for
example, a ventilation fan or a ventilation hole) separated from
the covering film, and the like.
[Frame]
[0216] The agricultural greenhouse according to the third aspect of
the present invention may have a frame over which the
aforementioned covering film and lining film (particularly, the
covering film) is spread.
[0217] Herein, the frame is not particularly limited, and it is
possible to use frameworks (for example, steel or steel pipes) used
in a plastic greenhouse and the like known in the related art.
[0218] In the third aspect of the present invention, the method for
installing the aforementioned lining film on the inside of the
aforementioned covering film is not particularly limited. Examples
of the method include a method in which an agricultural greenhouse
is prepared using the covering film and the frame, and then a
small-sized agricultural greenhouse is prepared within the space of
the aforementioned agricultural greenhouse by using the lining film
and the frame; a method in which an agricultural greenhouse is
prepared using the covering film and the frame, a curtain rail or a
wire is then installed in the vicinity of the boundary between the
roof portion and the wall surface portion of the agricultural
greenhouse, and the lining film is installed on these; and the
like.
[0219] It is preferable that the lining film is made movable by
being installed on a curtain rail or the like such that the lining
film can be installed during the night time or in the morning
during which the external temperature drops.
[0220] At the time of installing the lining film, the interspace
between the lining film and the covering film does not need to be
uniform. For example, as shown in FIG. 5, the lining film may be
installed such that only the roof portion of the lining film
becomes horizontal.
[Film for an Agricultural Greenhouse (Fourth Aspect)]
[0221] The film for an agricultural greenhouse according to the
fourth aspect of the present invention is a film for an
agricultural greenhouse which contains a cellulose acylate resin
and a plasticizer containing a polyether ester and/or a polyether
as an optional component and has a water vapor permeability equal
to or higher than 600 g/m.sup.2/24 h and a modulus of elasticity
less than 3.0 GPa.
[0222] Herein, the film for an agricultural greenhouse refers to a
film covering the frame (steel pipe) of a small house called a
plastic greenhouse (greenhouse). The film for an agricultural
greenhouse is an agricultural mulching film, that is, a film
different from the film which covers the surface of the soil for
preventing the field from drying (surface of the ground) or
suppressing weeds.
[0223] The water vapor permeability has the same definition as the
water vapor permeability described above for the film for an
agricultural greenhouse according to the first aspect of the
present invention.
[0224] Regarding the modulus of elasticity, a total of eight
samples having a length of 150 mm in a measurement direction and a
width of 15 mm are prepared by varying the orientation of cutting
in the measurement direction by 45.degree., and the average of
elastic moduli calculated for each of the samples is calculated and
taken as the modulus of elasticity. For calculating the modulus of
elasticity of each sample, each sample was left as it was for 24
hours in an environment with a temperature of 25.degree. C. and a
relative humidity of 60% and then immediately stretched at an
inter-chuck distance of 100 mm and a tensile rate of 200 mm/min in
the atmosphere with a temperature of 25.degree. C. and a relative
humidity of 60% by using a tensile tester "STROGRAPH" manufactured
by A&D Company, Limited; the stress applied at the time when
the sample was stretched by 0.1% and at the time when the sample
was stretched by 0.5% was measured; and from the slope thereof, the
modulus of elasticity was calculated.
[0225] In the fourth aspect of the present invention, by using the
film which contains a cellulose acylate resin, has a water vapor
permeability equal to or higher than 600 g/m.sup.2/24 h and a
modulus of elasticity of less than 3.0 GPa, both the drip-proofness
and the workability can be improved.
[0226] Hereinafter, the cellulose acylate resin and a predetermined
plasticizer will be specifically described.
<Cellulose Acylate Resin>
[0227] The cellulose acylate resin contained in the film for an
agricultural greenhouse according to the fourth aspect of the
present invention is not particularly limited, and examples of the
resin are the same as the examples of the cellulose acylate resin
contained in the film for an agricultural greenhouse according to
the first aspect of the present invention.
<Plasticizer>
[0228] It is preferable that the film for an agricultural
greenhouse according to the fourth aspect of the present invention
contains a plasticizer containing a polyether ester and/or a
polyether, because the drip-proofness and the workability of the
obtained film for an agricultural greenhouse according to the
fourth aspect of the present invention can then be further
improved, and the dew condensation can be prevented even when a
highly humid environment has been created in the greenhouse. The
plasticizer may contain a plasticizer component other than a
polyether ester and a polyether, or may be a plasticizer composed
only of a polyether ester and/or a polyether.
[0229] It is considered that the addition of the plasticizer may
further reduce the modulus of elasticity of the film, improve the
moisture content of the film, and make it easy for the water vapor
to enter the greenhouse.
(Polyether Ester)
[0230] Examples of the polyether ester suitably include a polyether
ester represented by the following Formula (A).
##STR00007##
[0231] In Formula (A), R.sup.1 represents a divalent aliphatic
hydrocarbon group having 2 to 10 carbon atoms, R.sup.2 each
independently represents a divalent aliphatic hydrocarbon group
having 2 to 6 carbon atoms, R.sup.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 each independently represents an integer of 1 to
20, and p represents an integer of 1 to 15.
[0232] A plurality of R.sup.1's, R.sup.2's, and n's contained in a
repeating unit may be the same as or different to each other.
[0233] The divalent aliphatic hydrocarbon group having 2 to 10
carbon atoms that is represented by R.sup.1 in Formula (A) may be
saturated or unsaturated, and may be any one of a divalent
chain-like and cyclic aliphatic hydrocarbon groups (for example, a
cycloalkylene group).
[0234] In a case where the divalent aliphatic hydrocarbon group is
a divalent chain-like aliphatic hydrocarbon group, the group may be
linear or branched, and preferred examples thereof include
ethylene, trimethylene, tetramethylene, pentamethylene,
hexamethylene, heptamethylene, octamethylene, nonamethylene,
decamethylene, propylene, 1,2-dimethylethylene,
1-methyltrimethylene, 2-methyltrimethylene, 2-methyltetramethylene,
2,2-dimethyltrimethylene, 1,2-cyclopentylene, 1,3-cyclopentylene,
1,2-cyclohexylene, 1,3-cyclohexylene, 1,4-cyclohexylene, and the
like.
[0235] The number of carbon atoms in the divalent aliphatic
hydrocarbon group is preferably 2 to 6, because then the modulus of
elasticity of the film can further be reduced, and the workability
can further be improved. The number of carbon atoms is more
preferably 4 to 6, because then the proportion of the plasticizer
eluted from the obtained film for an agricultural greenhouse due to
water or the like (hereinafter, simply referred to as an "elution
rate") can be reduced.
[0236] The divalent aliphatic hydrocarbon group having 2 to 6
carbon atoms that is represented by R.sup.2 in Formula (A) is
preferably a divalent linear aliphatic hydrocarbon group which may
be linear or branched.
[0237] The number of carbon atoms of the divalent aliphatic
hydrocarbon group is preferably 2 to 4, more preferably 2 or 3, and
even more preferably 2.
[0238] The divalent aliphatic hydrocarbon group having 2 to 6
carbon atoms is preferably a chain-like alkylene group, and
preferred examples thereof include ethylene, trimethylene,
tetramethylene, pentamethylene, hexamethylene, propylene,
1-methyltrimethylene, 2-methyltrimethylene, 1,2-dimethylethylene,
and 1-ethylethylene. Among these, ethylene, trimethylene,
propylene, tetramethylene, and 1-ethylethylene are more preferable,
ethylene, trimethylene, propylene, and tetramethylene are even more
preferable, and ethylene or propylene is most preferable.
[0239] As described above, R.sup.3 in Formula (A) 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.
[0240] Herein, the alkyl group having 1 to 20 carbon atoms that is
represented by R3 may be chain-like or cyclic. In a case where the
alkyl group is a chain-like aliphatic group, it may be linear or
branched and may have a substituent. The number of carbon atoms
thereof is preferably 1 to 12, more preferably 1 to 8, even more
preferably 1 to 4, and most preferably 1 or 2.
[0241] The aryl group having 6 to 20 carbon atoms that is
represented by R3 may have a substituent, and the number of carbon
atoms of the aryl group is preferably 6 to 15, more preferably 6 to
10, and even more preferably 6 to 8.
[0242] The acyl group having 2 to 20 carbon atoms that is
represented by R.sup.3 may be an aliphatic acyl group or an
aromatic acyl group, and these may have a substituent. In a case
where the acyl group is an aliphatic acyl group, the number of
carbon atoms thereof is preferably 2 to 18, more preferably 2 to 8,
and even more preferably 2 to 4. In a case where the acyl group is
an aromatic acyl group, the number of carbon atoms thereof is
preferably 7 to 18, more preferably 7 to 12, even more preferably 7
to 10, and most preferably 7 or 8.
[0243] In the present invention, R.sup.3 is preferably any one of a
hydrogen atom, an alkyl group having 1 to 20 carbon atoms, and an
aryl group having 6 to 20 carbon atoms, and more preferably a
hydrogen atom or an alkyl group having 1 to 20 carbon atoms.
R.sup.3 is even more preferably an alkyl group having 1 to 20
carbon atoms, because then the modulus of elasticity of the film
can be further reduced, and the workability can be further
improved.
[0244] n in Formula (A) represents an integer of 1 to 20. n is
preferably an integer of 1 to 15, more preferably an integer of 1
to 10, even more preferably an integer of 1 to 6, particularly
preferably an integer of 2 to 6, and most preferably an integer of
2 to 4.
[0245] Similarly, p in Formula (A) represents an integer of 1 to
15. n is preferably an integer of 1 to 10, more preferably an
integer of 1 to 5, even more preferably an integer of 1 to 3, and
particularly preferably an integer of 1 or 2, because then the
modulus of elasticity of the film can be further reduced. Herein, p
in Formula (A) is preferably an integer of 2 to 15 and more
preferably an integer of 2 to 10, because then the elution rate of
the plasticizer can be reduced.
(Method for Preparing Polyether Ester)
[0246] The method for preparing the aforementioned polyether ester
is not particularly limited. In a case where R.sup.3 in Formula (A)
is a hydrogen atom, for example, the polyether ester can be easily
synthesized by a thermal melting condensation method performed by
causing a polyesterification reaction, an ester exchange reaction
between a diol and dicarboxylic acid by a common method, or an
interfacial condensation method using an acid chloride of the above
acids and glycols.
[0247] "Plasticizer, Theory and Application thereof" (Koichi Murai,
SAIWAI SHOBO CO., LTD., first printing of first edition on Mar. 1,
1973) specifically describes polycondensed esters, and the
compounds described in the document can also be used.
[0248] Specific examples of the dicarboxylic acid include oxalic
acid, malonic acid, succinic acid, maleic acid, fumaric acid,
glutaric acid, adipic acid, pimelic acid, suberic acid,
1,4-cyclohexane dicarboxylic acid, and the like. Among these,
succinic acid, glutaric acid, adipic acid, and 1,4-cyclohexane
dicarboxylic acid are more preferable, and succinic acid, glutaric
acid, and adipic acid in which an aliphatic has 2 to 4 carbon atoms
are even more preferable.
[0249] In a case where R.sup.3 in Formula (A) is 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, the compound
represented by Formula (A) can be synthesized from a compound
represented by the following Formula (a) and the aforementioned
dicarboxylic acid by the aforementioned common method.
##STR00008##
[0250] R.sup.2, R.sup.3, and n in Formula (a) have the same
definitions as R.sup.2, R.sup.3, and n in Formula (A), and the
preferred range thereof is also the same. In a case where the
polyether ester is prepared from the aforementioned dicarboxylic
acid and the compound represented by Formula (a), p in Formula (A)
becomes 1.
[0251] In a case where R.sup.3 in Formula (A) is an acyl group
having 2 to 20 carbon atoms, for preparing the polyether ester, in
addition to the aforementioned preparation method, it is possible
to use a method of preparing a polyether ester in which R.sup.3
represents a hydrogen atom by the aforementioned method and then
introducing an acyl group into the polyether ester.
[0252] Herein, the introduction of the terminal acyl group can be
performed by, for example, a method of causing dehydrocondensation
with an alcohol by using carboxylic acid, a method of causing
acylation of an alcohol by using a carboxylic anhydride or a
carboxylic acid halide, a method of causing ester exchange by using
a carboxylic acid ester, and the like.
[0253] Specific examples of the polyether ester represented by
Formula (A) include polyether esters represented by Formula (A) in
which R.sup.1, R.sup.2, R.sup.3, n, and p are as described in the
following Table 1.
TABLE-US-00001 (A) ##STR00009## R.sup.1 R.sup.2 R.sup.3 n p HP-1
Ethylene Ethylene Hydrogen atom 1 1 HP-2 Ethylene Ethylene Hydrogen
atom 2 2 HP-3 Ethylene Ethylene Hydrogen atom 2 3 HP-4 Ethylene
Ethylene Hydrogen atom 3 1 HP-5 Ethylene Ethylene Methyl 2 1 HP-6
Ethylene Ethylene Methyl 3 1 HP-7 Ethylene Ethylene Methyl 4 1 HP-8
Ethylene Ethylene Butyl 2 1 HP-9 Ethylene Ethylene Butyl 3 1 HP-10
Ethylene Ethylene Octyl 3 1 HP-11 Ethylene Ethylene Acetyl 2 2
HP-12 Ethylene Ethylene Acetyl 3 1 HP-13 Ethylene Propylene
Hydrogen atom 2 1 HP-14 Ethylene Propylene Hydrogen atom 2 2 HP-15
Ethylene Propylene Hydrogen atom 3 2 HP-16 Ethylene Propylene
Methyl 2 1 HP-17 Ethylene Propylene Butyl 2 1 HP-18 Ethylene
Propylene Acetyl 2 2 HP-19 Ethylene Tetramethylene Benzoyl 1 2
HP-20 Ethylene Tetramethylene Hydrogen atom 3 2 HP-21 Trimethylene
Ethylene Hydrogen atom 2 2 HP-22 Trimethylene Ethylene Methyl 3 1
HP-23 Trimethylene Ethylene Benzyl 3 1 HP-24 Trimethylene Ethylene
Acetyl 3 3 HP-25 Tetramethylene Ethylene Hydrogen atom 1 2 HP-26
Tetramethylene Ethylene Hydrogen atom 2 2 HP-27 Tetramethylene
Ethylene Hydrogen atom 2 3 HP-28 Tetramethylene Ethylene Hydrogen
atom 3 1 HP-29 Tetramethylene Ethylene Hydrogen atom 3 2 HP-30
Tetramethylene Ethylene Methyl 3 1 HP-31 Tetramethylene Ethylene
Methyl 4 1 HP-32 Tetramethylene Ethylene Butyl 2 1 HP-33
Tetramethylene Ethylene Butyl 3 1 HP-34 Tetramethylene Ethylene
Methyl 3 2 HP-35 Tetramethylene Ethylene Acetyl 4 2 HP-36
Tetramethylene Propylene Hydrogen atom 2 2 HP-37 Tetramethylene
Propylene Hydrogen atom 3 2 HP-38 Tetramethylene Propylene Methyl 2
1 HP-39 Tetramethylene Propylene Butyl 2 1 HP-40 Tetramethylene
Propylene Methyl 3 1 HP-41 Tetramethylene Propylene Acetyl 2 2
HP-42 Tetramethylene Tetramethylene Hydrogen atom 3 1 HP-43
Pentamethylene Ethylene Hydrogen atom 3 2 HP-44 Pentamethylene
Ethylene Methyl 3 1 HP-45 Pentamethylene Ethylene Butyl 3 1 HP-46
Pentamethylene Propylene Hydrogen atom 2 2 HP-47 Hexamethylene
Ethylene Hydrogen atom 2 2 HP-48 Hexamethylene Ethylene Methyl 3 1
HP-49 Hexamethylene Ethylene Ethyl 3 1 HP-50 Hexamethylene
Trimethylene Acetyl 1 2
(Polyether)
[0254] Examples of the polyether include a polyether represented by
the following Formula (B).
##STR00010##
[0255] In Formula (B), R.sup.4 represents a divalent aliphatic
hydrocarbon group having 2 to 6 carbon atoms, R.sup.5 and R.sup.6
each independently represents a hydrogen atom, an alkyl group
having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon
atoms, an acyl group having 2 to 20 carbon atoms, a (meth)acryloyl
group, or a group represented by the following Formula (b) obtained
by polymerization of a (meth)acryloyl group, and m represents an
integer of 1 to 20.
[0256] A plurality of R.sup.4's contained in a repeating unit may
be the same as or different to each other.
[0257] In the present specification, a "(meth)acryloyl group" means
an acryloyl group (CH.sub.2=CHCO--) or a methacryloyl group
(CH.sub.2=C(CH.sub.3)CO--).
##STR00011##
[0258] In Formula (b), * represents an oxygen atom bonded to
R.sup.5 or R.sup.6 in Formula (B), R.sup.7 represents a hydrogen
atom or a methyl group, q represents an integer of 1 to 10, and a
plurality of R.sup.7's contained in a repeating unit may be the
same as or different to each other.
[0259] Examples of the divalent aliphatic hydrocarbon group having
2 to 6 carbon atoms that is represented by R.sup.4 in Formula (B)
are the same as the examples of R.sup.2 in Formula (A).
[0260] As described above, R.sup.5 and R.sup.6 in Formula (B)
represent a hydrogen atom, an alkyl group having 1 to 20 carbon
atoms, an aryl group having 6 to 20 carbon atoms, an acyl group
having 2 to 20 carbon atoms, a (meth)acryloyl group, or a group
represented by Formula (b) obtained by the polymerization of a
(meth)acryloyl group. Examples of functional groups other than a
(meth)acryloyl group and a group represented by Formula (b)
obtained by the polymerization of a (meth)acryloyl group are the
same as the examples of R.sup.3 in Formula (A).
[0261] Among these, the polyether in which R.sup.5 is an aryl group
(particularly, a phenyl group) having 6 to 20 carbon atoms or a
(meth)acryloyl group is preferable, because the polyether can widen
the internal space of the fiber of the cellulose acylate resin and
can further increase the water vapor permeability of the obtained
film for an agricultural greenhouse.
[0262] Furthermore, the polyether in which R.sup.6 is a hydrogen
atom is preferable, because the polyether can impart hydrophilicity
to the cellulose acylate resin and can further increase the water
vapor permeability of the obtained film for an agricultural
greenhouse.
[0263] m in Formula (B) represents an integer of 1 to 20. m is
preferably an integer of 1 to 15, more preferably an integer of 1
to 10, even more preferably an integer of 1 to 6, particularly
preferably an integer of 2 to 6, and most preferably an integer of
2 to 4.
[0264] Specific examples of the polyether represented by Formula
(B) include polyethylene glycol, polypropylene glycol,
polytetramethylene glycol, and the like.
[0265] Examples of other polyethers represented by Formula (B)
include polyethers obtained by repeating a reaction once or more
times by which ring-opening addition of alkylene oxide (for
example, ethylene oxide or propylene oxide), which contains
ethylene oxide in at least a portion thereof, to phenols, hydroxyl
group-containing (meth)acrylate, or the like occurs as illustrated
in the synthesis examples among the examples that will be described
later.
[0266] In the fourth aspect of the present invention, in a case
where the film for an agricultural greenhouse contains a
plasticizer, the content of the plasticizer, with respect to 100
parts by mass of the cellulose acylate resin, is preferably 10 to
70 parts by mass, more preferably 20 to 60 parts by mass, even more
preferably 30 to 60 parts by mass, and particularly preferably 40
to 60 parts by mass.
<Additives>
[0267] Depending on the usage environment, the film for an
agricultural greenhouse according to the fourth aspect of the
present invention may contain additives such as a deterioration
preventing agent and an ultraviolet absorbent.
[0268] Specific examples of the deterioration preventing agent
include a hindered amine-based light stabilizer, an antioxidant, a
peroxide decomposer, a radical inhibitor, a metal deactivator, an
acid acceptor, an amine, and the like.
[0269] The ultraviolet absorbent can absorb ultraviolet rays, and
any of known ultraviolet absorbents can be used. Examples thereof
suitably include ultraviolet absorbents based on benzotriazole or
hydroxyphenyltriazine.
[0270] In a case where the aforementioned deterioration preventing
agent or ultraviolet absorbent is added, it is preferable to
incorporate the additive into a cellulose acylate solution (dope),
which will be described later, in an amount of 0.01% to 10% by
mass.
<Matting Agent>
[0271] Depending on the usage environment, the film for an
agricultural greenhouse according to the fourth aspect of the
present invention may contain a matting agent.
[0272] As the matting agent, any one of organic and inorganic
particles can be used.
[0273] Examples of the particles include silicon dioxide, titanium
dioxide, aluminum oxide, zirconium oxide, calcium carbonate, talc,
clay, fired kaolin, fired calcium silicate, hydrated calcium
silicate, aluminum silicate, magnesium silicate, and calcium
phosphate.
[0274] These particles form secondary particles which generally
have an average particle size of 0.1 to 3.0 .mu.m. These particles
exist as an aggregate of primary particles in the film, and form
irregularities having a size of 0.1 to 3.0 .mu.m on the surface of
the film. The average secondary particle size is preferably 0.2
.mu.m to 1.5 .mu.m, more preferably 0.4 .mu.m to 1.2 .mu.m, and
most preferably 0.6 .mu.m to 1.1 .mu.m. In order to determine the
primary and secondary particle sizes, the particles in the film
were observed using a scanning electron microscope, and the
diameters of circles circumscribed around the particles were used
as the particle sizes. Furthermore, 200 particles were observed by
changing spots, and the average thereof was taken as an average
particle size.
[0275] The amount of particles added that is represented by a mass
ratio, with respect to the cellulose acylate, is preferably 1 ppm
to 5,000 ppm, more preferably 5 ppm to 1,000 ppm, and even more
preferably 10 ppm to 500 ppm.
[0276] It is preferable that the particles contain silicon because
the haze can then be controlled. Particularly, silicon dioxide is
preferable. The silicon dioxide particles preferably have an
average primary particle size equal to or less than 25 nm and an
apparent specific gravity equal to or greater than 30 g/L. From the
viewpoint of reducing the haze of the film, the average primary
particle size is preferably as small as 5 to 20 nm. The apparent
specific gravity is preferably equal to or greater than 90 to 200
g/L, and even more preferably equal to or greater than 100 to 200
g/L. It is preferable that the particles have high apparent
specific gravity, because then a high-concentration dispersion can
be prepared, and the haze and the aggregate can be ameliorated.
[0277] As the silicon dioxide particles, for example, it is
possible to use commercially available products such as AEROSIL
NX90S, R972, R972V, R974, R812, 200, 200V, 300, R202, OX50, and
TT600 (all manufactured by NIPPON AEROSIL CO., LTD.). As zirconium
oxide particles, for example, those marketed in the trade name of
AEROSIL R976 and R811 (all manufactured by NIPPON AEROSIL CO.,
LTD.) can be used.
[0278] Among these, AEROSIL 200V and AEROSIL R972V are the silicon
dioxide particles having an average primary particle size equal to
or less than 20 nm and an apparent specific gravity equal to or
greater than 70 g/L. These silicon dioxide particles are
particularly preferable because they have a strong effect of
reducing the frictional coefficient while keeping the haze of the
film for an agricultural greenhouse at a low level.
[0279] The film for an agricultural greenhouse according to the
fourth aspect of the present invention may have a single layered
structure or a laminated structure, but it is preferable that the
film has a single layered structure.
[0280] The thickness of the film for an agricultural greenhouse is
preferably 60 .mu.m to 200 .mu.m, more preferably 60 .mu.m to 150
.mu.m, and even more preferably 80 .mu.m to 120 .mu.m, because then
the workability of the obtained film for an agricultural greenhouse
according to the fourth aspect of the present invention can be
further improved.
<Method for Manufacturing Film for an Agricultural
Greenhouse>
[0281] The method for manufacturing the film for an agricultural
greenhouse according to the fourth aspect of the present invention
is not particularly limited. Examples of the method are the same as
the examples of the method described above for the film for an
agricultural greenhouse according to the first aspect of the
present invention.
[0282] In a case where the film for an agricultural greenhouse
according to the fourth aspect of the present invention contains a
plasticizer, the timing of blending the plasticizer is not
particularly limited as long as the plasticizer is added at a point
in time when cellulose acylate film is formed. For example, the
plasticizer may be added at a point in time when cellulose acylate
is synthesized [for example, the aforementioned precipitation
step], or may be mixed with cellulose acylate at the time when dope
is prepared as shown in examples which will be described later.
EXAMPLES
[First Aspect]
[0283] Hereinafter, the first aspect of the present invention will
be more specifically described based on examples. The materials and
the amount thereof used, the proportion of the materials, the
treatment content, the treatment procedure, and the like shown in
the following examples can be appropriately changed within a scope
that does not depart from the gist of the present invention.
Accordingly, the scope of the present invention is not limited to
the following examples.
<Synthesis of Plasticizer>
[0284] By the following method, polyether esters were synthesized
as ester-based plasticizers A to C used in Examples 1-2 and 1-3 and
Comparative Example 1-1. Regarding each of the synthesized
polyether esters, the number of polymerized monomers (n), the
number of polymerized monomers (p), and the terminal (R.sup.3) in
Formula (A) are shown in the following Table 1.
(Plasticizer A--Used in Example 1-2)
[0285] Succinic acid and triethylene glycol were polyesterified by
a thermal melting condensation method, thereby synthesizing a
polyether ester.
(Plasticizer B--Used in Example 1-3)
[0286] Monoethylene glycol and tetraethylene glycol were added to
adipic acid at a content ratio (monoethylene glycol/tetraethylene
glycol) of 70/30 and polyesterified by a thermal melting
condensation method, thereby synthesizing a polyether ester.
(Plasticizer C--Used in Comparative Example 1-1)
[0287] Adipic acid and monoethylene glycol were polyesterified by a
thermal melting condensation method, thereby synthesizing a
polyether ester.
TABLE-US-00002 TABLE 1 Ester-based plasticizer Diol 1 Diol 2 Number
of Number of Number of polymerized polymerized polymerized Table 1
Dicarboxylic acid monomers monomers monomers Terminal No. Type Type
(n) Type (n) (p) (R.sup.3) A Succinic acid Triethylene 3 -- -- 1
Hydrogen glycol atom B Adipic acid Monoethylene 1 Tetraethylene 4 9
Hydrogen glycol glycol atom C Adipic acid Monoethylene 1 -- -- 5
Hydrogen glycol atom
Example 1-1
<Preparation of Dope>
[0288] The following composition was put into a mixing tank and
stirred such that each component dissolved, thereby preparing a
cellulose acetate solution.
TABLE-US-00003 Cellulose acylate 100 parts by mass (degree of
acetyl group substitution: 2.86, viscosity average polymerization
degree: 320) Silica particle dispersion (average particle 1.3 parts
by mass size: 16 nm) "AEROSIL R972" manufactured by NIPPON AEROSIL
CO., LTD Methylene chloride 635 parts by mass Methanol 125 parts by
mass
<Formation of Film>
[0289] The dope whose temperature was adjusted to be 30.degree. C.
was uniformly cast on an endless stainless steel belt (support)
such that the film thickness after drying became 120 .mu.m.
[0290] Immediately after casting, the dope film (web) on the belt
was dried by being exposed to hot air with a temperature of
100.degree. C. Then, 120 seconds after casting, the film was peeled
at a peeling tension of 150 N/m and dried while being transported
by a large number of rolls at a transport tension of 100 N/m. The
temperature of the endless stainless steel belt in the peeling
portion was set to be 10.degree. C. The amount of the residual
solvent at the time of peeling was 100% by mass.
[0291] The film was dried by being transported for 5 minutes within
a first drying zone set to be 80.degree. C. and then for 10 minutes
within a second drying zone set to be 120.degree. C. After being
dried, the film was wound into the form of a roll, thereby
preparing a film having a film width of 1.5 m, a rolled length of
2,000 m, and a film thickness of 120 .mu.m (in the following Table
2, described as "cellulose-based (unplasticized)"). The amount of
the residual solvent at the time of winding was 0.3% by mass.
Example 1-2
[0292] A film having a film width of 1.5 m, a rolled length of
2,000 m, and a film thickness of 120 .mu.m (in the following Table
2, described as "cellulose-based (plasticizer A)") was prepared by
the same method as in Example 1-1, except that a dope obtained by
further blending 60 parts by mass of the plasticizer A with the
dope prepared in Example 1-1 was used.
Example 1-3
[0293] A film having a film width of 1.5 m, a rolled length of
2,000 m, and a film thickness of 120 .mu.m (in the following Table
2, described as "cellulose-based (plasticizer B)") was prepared by
the same method as in Example 1-1, except that a dope obtained by
further blending 60 parts by mass of the plasticizer B with the
dope prepared in Example 1-1 was used.
Example 1-4
[0294] A film having a film width of 1.5 m, a rolled length of
2,000 m, and a film thickness of 120 .mu.m (in the following Table
2, described as "cellulose-based (unplasticized)") was prepared by
the same method as in Example 1-1, except that "cellulose acylate
(degree of acetyl group substitution: 2.86, viscosity average
polymerization degree: 320)" in the dope prepared in Example 1-1
was changed to "cellulose acylate (degree of acetyl group
substitution: 2.40, viscosity average polymerization degree:
320)".
Example 1-5
[0295] A film having a film width of 1.5 m, a rolled length of
2,000 m, and a film thickness of 120 .mu.m (in the following Table
2, described as "cellulose-based (unplasticized)") was prepared by
the same method as in Example 1-1, except that "cellulose acylate
(degree of acetyl group substitution: 2.86, viscosity average
polymerization degree: 320)" in the dope prepared in Example 1-1
was changed to "cellulose acylate (degree of acetyl group
substitution: 2.95, viscosity average polymerization degree:
320)".
Comparative Example 1-1
[0296] A film having a film width of 1.5 m, a rolled length of
2,000 m, and a film thickness of 120 .mu.m (in the following Table
2, described as "cellulose-based (plasticizer C)") was prepared by
the same method as in Example 1-1, except that a dope obtained by
further blending 15 parts by mass of the plasticizer C with the
dope prepared in Example 1-1 was used.
Comparative Example 1-2
[0297] As a fluorine-based film, a product named "F-CLEAN
(registered trademark) SHIZENKORYUTEKI" manufactured by AGC
Green-Tech Co., Ltd was used.
Comparative Example 1-3
[0298] As a vinyl-based film, a product named "NOBI-ACE-MIRAI
(registered trademark)" manufactured by Mitsubishi Plastics Agri
Dream Co., Ltd was used.
[0299] For each of the prepared films or the commercially available
films used, water vapor permeability, equilibrium moisture content,
light transmittance, CO.sub.2 permeability coefficient, and
CO.sub.2 permeability were measured and evaluated by the following
methods. The results are shown in the following Table 2.
<Water Vapor Permeability>
[0300] For each film, according to the technique described in JIS Z
0208:1976 "Testing methods for determination of the water vapor
permeability of moisture-proof packaging materials (cup method)",
the amount (g/m.sup.2/24 h) of water vapor passing through the film
for 24 hours under the conditions of a temperature of 40.degree. C.
and a relative humidity of 90% was measured.
<Equilibrium Moisture Content>
[0301] From each film, 500 mg of a sample was collected and
humidified for 24 hours in an environment with a relative humidity
of 80%, and then the amount of moisture thereof was measured using
a Karl Fischer moisture meter (AQ-2200, manufactured by HIRANUMA
SANGYO Co., LTD.).
<Light Transmittance>
[0302] For each film, the transmittance at a wavelength region (400
to 700 nm) effective for photosynthesis was measured using a
spectrophotometer (manufactured by Jasco Engineering and Sales,
Inc.: V-560), and the average thereof was calculated.
<CO.sub.2 Permeability Coefficient>
(1) Dry Film Condition
[0303] Each film was humidified for 24 hours or longer in an
environment with a temperature of 25.degree. C. and a relative
humidity of 55%, and then measured at a temperature of 40.degree.
C. within a sample evaluation area of 3.14 cm.sup.2. Caron dioxide
was supplied to the surface (supply side) of the sample under a
pressure of 800 kPa, and the pressure of the back surface
(permeation side) of the sample was reduced down to 3 Pa by using a
vacuum pump. The vacuum pump was then stopped, the pressure change
in the permeation side was recorded, and the permeation coefficient
was calculated by a dime-delay method according to JIS K
6275-1.
(2) Humid Film Condition
[0304] For each film, the CO.sub.2 permeability coefficient was
measured under humid film conditions (environment with room
temperature (25.degree. C.) and a relative humidity of 80%) by the
measurement method described above.
<CO.sub.2 Permeability (Humid Film Condition)>
[0305] The CO.sub.2 permeability was calculated by the following
equation by using the CO.sub.2 permeability coefficient (unit:
1.times.10.sup.-10 cm.sup.3cm/(scm.sup.2cmHg)) measured under humid
film conditions.
T(CO.sub.2 permeability)=(CO.sub.2 permeability
coefficient.times.surface area of film.times.pressure
difference)/film thickness
TABLE-US-00004 TABLE 2 CO.sub.2 permeability CO.sub.2 coefficient
permeability Degree of Water 1 .times. 10.sup.-10 cm.sup.3cm/
cm.sup.3/ acetyl vapor Equilibrium Light (scm.sup.2cmHg)
(scm.sup.2cmHg) Thickness group permeability moisture transmittance
Dry film Humid film Humid film Table 2 Film .mu.m substitution
g/m.sup.2/24h content % % condition condition condition Example 1-1
Cellulose-based 120 2.86 1,000 5.22 93 11 800 6.7E-06
(unplasticized) Example 1-2 Cellulose-based 120 2.86 900 4.10 93 71
600 5.0E-06 (plasticizer A) Example 1-3 Cellulose-based 120 2.86
1,200 4.34 93 75 870 7.3E-06 (plasticizer B) Example 1-4
Cellulose-based 120 2.40 1,100 7.80 93 20 2,000 1.7E-05
(unplasticized) Example 1-5 Cellulose-based 120 2.95 900 4.90 93 3
700 5.8E-06 (unplasticized) Comparative Cellulose-based 120 2.86
530 3.10 93 5.22 70 5.8E-07 Example 1-1 (plasticizer C) Comparative
Fluorine-based 100 -- 20 0.01 87 18.27 20 2.0E-07 Example 1-2
Comparative Vinyl chloride- 75 -- 40 0.02 86 0.29 0.4 5.3E-09
Example 1-3 based
[0306] From the results shown in Table 2, it was understood that
even though the film contains a cellulose acylate resin, if the
equilibrium moisture content is less than 4% at a temperature of
25.degree. C. and a relative humidity of 80%, the CO.sub.2
permeability is reduced (Comparative Example 1-1).
[0307] Furthermore, it was understood that, in a case where a
fluorine-based film or a vinyl chloride-based film not containing a
cellulose acylate resin is used, the equilibrium moisture content
is extremely low, and the CO.sub.2 permeability coefficient and the
CO.sub.2 permeability at the time of humidifying the film are
reduced (Comparative Example 1-2 and 1-3).
[0308] In contrast, it was understood that, in a case where the
film which contains a cellulose acylate resin and has an
equilibrium moisture content of 4% to 8% at a temperature of
25.degree. C. and relative humidity of 80% is used, both the
CO.sub.2 permeability coefficient and the CO.sub.2 permeability at
the time of humidifying the film are increased (Examples 1-1 to
1-5).
[0309] Furthermore, from the comparison of Examples 1-1 to 1-5 and
Comparative Example 1-1, it was understood that, by the degree of
acetyl group substitution of cellulose acylate or the type of
plasticizer, the equilibrium moisture content or the CO.sub.2
permeability coefficient be adjusted. Particularly, from the
comparison of Examples 1-1, 1-4 and 1-5, it was understood that
Example 1-4 in which the degree of acetyl group substitution is
within a range of 2.2 to 2.6, the equilibrium moisture content
increases, and the CO.sub.2 permeability coefficient and the
CO.sub.2 permeability at the time of humidifying the film further
increase.
[Preparation of Agricultural Greenhouse]
[0310] In Miyanodai, Minamiashigara-shi, a framework with a size of
6 m.times.9 m.times.4 m (height) was set up, and each of the films
shown in the following Table 3 that were prepared and used in
Examples 1-1 to 1-5 and Comparative Examples 1-1 to 1-3 was spread
over the frame, thereby preparing an agricultural greenhouse.
[0311] Furthermore, a thermometer and a CO.sub.2 concentration
meter were installed in a position 1.5 m above the central ground
in the prepared agricultural greenhouse.
[0312] For the prepared agricultural greenhouse, the internal
CO.sub.2 concentration and the external CO.sub.2 concentration of
the greenhouse were measured during the daytime (13:00) on a clear
day in October 2014, and the internal temperature and the external
temperature of the greenhouse were also measured. The results are
shown in the following Table 3. The external temperature of the
greenhouse was 17.degree. C., and the relative humidity was
89%.
TABLE-US-00005 TABLE 3 Internal temperature and CO.sub.2
concentration humidity of greenhouse Equilibrium (13:00) (13:00)
moisture Inside of Outside of Ratio Relative content greenhouse
greenhouse (inside of greenhouse/ Temperature humidity Table 3 Film
% ppm ppm outside of greenhouse .degree. C. % Example 1-1
Cellulose-based 5.22 380 400 95% 27.5 76 (unplasticized) Example
1-2 Cellulose-based 4.10 330 400 83% 27.0 73 (plasticizer A)
Example 1-3 Cellulose-based 4.34 350 400 88% 28.2 70 (plasticizer
B) Example 1-4 Cellulose-based 7.80 400 400 100% 27.5 72
(unplasticized) Example 1-5 Cellulose-based 4.90 330 400 83% 27.7
80 (unplasticized) Comparative Cellulose-based 3.10 300 400 75%
29.0 87 Example 1-1 (plasticizer C) Comparative Fluorine-based 0.01
290 400 73% 28.4 85 Example 1-2 Comparative Vinyl chloride- 0.02
200 400 50% 27.3 91 Example 1-3 based
[0313] From the results shown in Table 3, it was understood that,
even though the him contains a cellulose acylate resin, if the
equilibrium moisture content is less than 4% at a temperature of
25.degree. C. and a relative humidity of 80%, a ratio between the
internal CO.sub.2 concentration of the greenhouse and the external
CO.sub.2 concentration of the greenhouse (inside of
greenhouse/outside of greenhouse) [hereinafter, simply described as
"CO.sub.2 concentration ratio" in the present paragraph] is reduced
(Comparative Example 1-1).
[0314] Furthermore, it was understood that, in a case where a
fluorine-based film or a vinyl chloride-based film not containing a
cellulose acylate resin is used, the equilibrium moisture content
is extremely low, and the CO.sub.2 concentration ratio is reduced
(Comparative Examples 1-2 and 1-3).
[0315] In contrast, it was understood that, in a case where the
film which contains a cellulose acylate resin and has an
equilibrium moisture content of 4% to 8% at a temperature of
25.degree. C. and a relative humidity of 80% is used, the CO.sub.2
concentration ratio becomes equal to or higher than 80% in all
cases, and a CO.sub.2 concentration necessary for the
photosynthesis can be maintained.
[0316] Particularly, from the comparison of Examples 1-1, 1-4, and
1-5, it was understood that, in Example 1-4 in which the degree of
acetyl group substitution is within a range of 2.2 to 2.6, the
equilibrium moisture content increases, the CO.sub.2 concentration
ratio becomes 100%, and the CO.sub.2 concentration can be
maintained at the same level as the external CO.sub.2 concentration
of the greenhouse.
[Growth of Plant]
[0317] In the agricultural greenhouse using each of the films
prepared and used in Examples 1-1 and Comparative Examples 1-2 and
1-3, three varieties including large-sized tomatoes (MISORA),
medium-sized tomatoes (FRUTIKA), and mini tomatoes (FABRYSAKURA)
were grown from September through to November 2014. The yields of
tomatoes harvested for 1 month during which the growth was
stabilized were compared.
[0318] The results of growth (yield) are shown in the following
Table 4.
TABLE-US-00006 TABLE 4 CO.sub.2 concentration (13:00) Equilibrium
Inside of Outside of Ratio (inside of moisture greenhouse
greenhouse greenhouse/outside Yield Table 4 Film content % ppm ppm
of greenhouse) kg/m.sup.2month Example1-1 Cellulose-based 5.22 380
400 95% 0.56 (unplasticized) Comparative Fluorine-based 0.01 290
400 73% 0.37 Example 1-2 Comparative Vinyl chloride- 0.02 200 400
50% 0.38 Example 1-3 based
[0319] From the results shown in Table 4, it was understood that
the agricultural greenhouse using the cellulose film, which
contains a cellulose acylate resin and has an equilibrium moisture
content of 4% to 8% at a temperature of 25.degree. C., a relative
humidity of 80% and a thickness of 60 to 200 .mu.m, can maintain
the CO.sub.2 concentration, and accordingly, the yield in the
agricultural greenhouse is higher than that in the agricultural
greenhouse using a fluorine-based film or a vinyl chloride-based
film.
[Second Aspect]
[0320] Hereinafter, the second aspect of the present invention will
be more specifically described based on examples. The materials and
the amount thereof used, the proportion of the materials, the
treatment content, the treatment procedure, and the like shown in
the following examples can be appropriately changed within a scope
that does not depart from the gist of the present invention.
Accordingly, the scope of the present invention is not limited to
the following examples.
[Preparation of Film 1]
<Preparation of Dope>
[0321] The following composition was put into a mixing tank and
stirred such that each component dissolved, thereby preparing a
cellulose acetate solution.
TABLE-US-00007 Cellulose acylate 100 parts by mass (degree of
acetyl group substitution: 2.86, viscosity average polymerization
degree: 320) Silica particle dispersion (average particle 1.3 parts
by mass size: 16 nm) "AEROSIL R972" manufactured by NIPPON AEROSIL
CO., LTD Methylene chloride 635 parts by mass Methanol 1.3 parts by
mass
<Formation of Film 1>
[0322] The dope whose temperature was adjusted to be 30.degree. C.
was uniformly cast on an endless stainless steel belt (support)
such that the film thickness after drying became 100 .mu.m.
[0323] Immediately after casting, the dope film (web) on the belt
was dried by being exposed to hot air with a temperature of
100.degree. C. Then, 120 seconds after casting, the film was peeled
at a peeling tension of 150 N/m and dried while being transported
by a large number of rolls at a transport tension of 100 N/m. The
temperature of the endless stainless steel belt in the peeling
portion was set to be 10.degree. C. The amount of the residual
solvent at the time of peeling was 100% by mass.
[0324] The film was dried by being transported for 5 minutes within
a first drying zone set to be 80.degree. C. and then for 10 minutes
within a second drying zone set to be 120.degree. C. After being
dried, the film was wound in the form of a roll, thereby obtaining
a cellulose-based film 1 having a film width of 1.5 m, a rolled
length of 2,000 m, and a film thickness of 100 .mu.m. The amount of
the residual solvent at the time of winding was 0.3% by mass.
[Preparation of Film 2]
[0325] A cellulose-based film 2 having a film width of 1.5 m, a
rolled length of 2,000 m, and a film thickness of 120 .mu.m was
obtained by the same method as used for preparing the film 1,
except that dope was uniformly cast on an endless stainless steel
belt (support) such that the film thickness after drying became 120
.mu.m.
[Film 3]
[0326] As a fluorine-based film 3, a product named "F-CLEAN
(registered trademark) SHIZENKORYUTEKI" manufactured by AGC
Green-Tech Co., Ltd was used.
[0327] For each of the prepared films or the commercially available
films used, a water vapor permeability and a light transmittance
were measured and evaluated by the following methods. The results
are shown in the following Table 5.
<Water Vapor Permeability>
[0328] For each film, according to the technique described in JIS Z
0208:1976 "Testing methods for determination of the water vapor
permeability of moisture-proof packaging materials (cup method)",
the amount (g/m.sup.2/24 h) of water vapor passing through the film
for 24 hours under the conditions of a temperature of 40.degree. C.
and a relative humidity of 90% was measured.
<Light Transmittance>
[0329] For each film, the transmittance of light at 555 nm was
measured using a spectrophotometer (manufactured by Jasco
Engineering and Sales, Inc.: V-560).
Examples 2-1 to 2-3 and Comparative Examples 2-1 and 2-2
<Preparation of Agricultural Greenhouse>
[0330] In Miyanodai, Minamiashigara-shi, a framework with a size of
6 m.times.9 m.times.4 m (height) was set up, and each of the films
shown in the following Table 5 was spread over the frame, thereby
preparing an agricultural greenhouse.
[0331] In addition, to the ceiling of the prepared agricultural
greenhouse, a mist cooling device (air cooler AC 4543, manufactured
by FULTA ELECTRIC MACHINERY CO. LTD) was fixed in a pendant
state.
[0332] Furthermore, a thermo-hygrometer was installed in a position
1.5 m above the central ground in the agricultural greenhouse, and
a water gauge measuring the spray amount was installed immediately
before the water inlet port of the mist cooling device.
<Growth of Plant>
[0333] In July 2014, 38 large-sized tomato plants (MISORA), 35
medium-sized tomato plants (FURUTIKA), and 70 mini tomato plants
(FABRYSAKURA) were grown in the prepared agricultural
greenhouse.
[0334] At noon (12:00) on a clear day in July 2014, the mist
cooling device was moved such that the mist was sprayed by the
amount shown in the following Table 5. After 2 hours, at 14:00, the
internal temperature, the internal relative humidity of the
greenhouse as well as whether or not dew condensation occurred were
checked. The external temperature and the external relative
humidity of the greenhouse at 14:00 are shown in the following
Table 5.
[0335] In Examples 2-1 to 2-3 and Comparative Examples 2-1 and 2-2,
the mist cooling was performed without conducting ventilation at
the time of moving the mist cooling device. In Comparative Example
2-3 which will be described later, mist cooling was performed with
ventilation.
Comparative Example 2-3
[0336] The plants were grown by performing mist cooling under the
same conditions as in Comparative Example 2-1, except that, between
7:00 and 17:00, both sides of the film (9 m.times.1.5 m) of the
lateral surface of the greenhouse were rolled up so as to perform
ventilation.
[0337] Although insect-proof mesh was mounted on the opening
portion that was exposed when the film was rolled up, it was
confirmed that the growing tomatoes were damaged by insects such as
Bemisia tabaci or Agromyzidae.
TABLE-US-00008 TABLE 5 Outside of Film Amount Inside of greenhouse
greenhouse Water vapor Light of mist Temper- Relative In mist
Temper- Relative Thickness permeability transmit- sprayed ature
humidity Dew con- In mist ature humidity Table 5 No. Material .mu.m
g/m.sup.2/24 h tance % g/m.sup.2min .degree. C. % densation
Ventilation .degree. C. % Example 2-1 1 Cellulose- 100 1,000 90 14
38.2 91 Not Not 36.5 41 based occurred performed Example 2-2 2
Cellulose- 120 800 91 14 40.7 86 Not Not 36.6 42 based occurred
performed Example 2-3 1 Cellulose- 100 1,000 90 7 43.5 84 Not Not
36.4 41 based occurred performed Comparative 3 Fluorine- 100 20 85
14 44.9 100 Occurred Not 34.8 43 Example 2-1 based performed
Comparative 3 Fluorine- 100 20 85 7 49.3 100 Occurred Not 35.1 42
Example 2-2 based performed Comparative 3 Fluorine- 100 20 85 14
43.2 75 Not Performed 33.7 45 Example 2-3 based occurred
[0338] As shown in Table 5, from the comparison of Examples 2-1 and
2-2 and Comparative Example 2-1, it was understood that, even when
the amount of mist sprayed by mist cooling is the same, the
agricultural greenhouse using a cellulose film, which contains a
cellulose acylate resin and has a water vapor permeability equal to
or higher than 600 g/m.sup.2/24 h and a thickness of 80 to 200
.mu.m, can reduce the internal temperature and the internal
relative humidity of the greenhouse and can inhibit the occurrence
of dew condensation of the mist.
[0339] Similarly, from the comparison of Example 2-3 and
Comparative Example 2-2, it was understood that, even when the
amount of mist sprayed by mist cooling is the same, the
agricultural greenhouse using a cellulose film, which has a water
vapor permeability equal to or higher than 600 g/m.sup.2/24 h and a
thickness of 80 to 200 .mu.m, can reduce the internal temperature
and the internal relative humidity of the greenhouse and can
inhibit the occurrence of dew condensation of the mist.
[0340] In contrast, in Comparative Example 2-3 in which ventilation
was performed to inhibit the occurrence of dew condensation during
mist cooling and to reduce the temperature, as described above, it
was confirmed that the growing tomatoes were damaged by insects
such as Bemisia tabaci or Agromyzidae.
[0341] From the above results, it was understood that the
agricultural greenhouse using a cellulose film, which contains a
cellulose acylate resin and has a water vapor permeability equal to
or higher than 600 g/m.sup.2/24 h and a thickness of 80 to 200
.mu.m, does not require ventilation means and can inhibit the
inflow of pests.
[0342] For the agricultural greenhouses prepared in Examples 2-1
and 2-2 and Comparative Example 2-1, whether or not dew
condensation occurred within the time period from night to morning
during which mist cooling was not performed, was observed.
[0343] As a result, it was confirmed that, while dew condensation
occurs in the agricultural greenhouse prepared in Comparative
Example 2-1, it does not occur in the agricultural greenhouses
prepared in Example 2-1 and 2-2.
[0344] Therefore, it was understood that the agricultural
greenhouse using a cellulose film, which contains a cellulose
acylate resin and has a water vapor permeability equal to or higher
than 600 g/m.sup.2/24 h and a thickness of 80 to 200 .mu.m, does
not require ventilation means, can inhibit the inflow of pests, and
is useful even during a time period of when the mist cooling is not
performed.
[0345] For the agricultural greenhouses prepared in the same manner
as in Example 2-1 and Comparative Example 2-1, the internal carbon
dioxide concentration of the greenhouse and the external carbon
dioxide concentration were measured from Jul. 20 to 25, 2014. The
results are shown in FIG. 7. The mist cooling device was moved for
10 hours from 7:00 to 17:00 under the condition of a spray amount
of 14 g/m.sup.2min.
[0346] From the results shown in FIG. 7, it was understood that the
agricultural greenhouse prepared in Example 2-1 can maintain the
carbon dioxide concentration at a level approximately the same as
the carbon dioxide concentration in the external air even during
the daytime when plants photosynthesize.
[0347] Therefore, it was understood that the agricultural
greenhouse using a cellulose film, which contains a cellulose
acylate resin and has a water vapor permeability equal to or higher
than 600 g/m.sup.2/24 h and a thickness of 80 to 200 .mu.m, does
not require ventilation means, can inhibit the inflow of pests, and
has an effect of being able to maintain the carbon dioxide
concentration at a level approximately the same as the carbon
dioxide concentration in the external air.
[Third Aspect]
[0348] Hereinafter, the third aspect of the present invention will
be more specifically described based on examples. The materials and
the amount thereof used, the proportion of the materials, the
treatment content, the treatment procedure, and the like shown in
the following examples can be appropriately changed within a scope
that does not depart from the gist of the present invention.
Accordingly, the scope of the present invention is not limited to
the following examples.
[Preparation of Triacetyl Cellulose (TAC) Film]
<Preparation of Dope>
[0349] The following composition was put into a mixing tank and
stirred such that each component dissolved, thereby preparing a
cellulose acetate solution.
TABLE-US-00009 Cellulose acylate 100 parts by mass (degree of
acetyl group substitution: 2.86, viscosity average polymerization
degree: 320) Silica particle dispersion (average particle 1.3 parts
by mass size: 16 nm) "AEROSIL R972" manufactured by NIPPON AEROSIL
CO., LTD Methylene chloride 635 parts by mass Methanol 1.3 parts by
mass
<Formation of TAC Film>
[0350] The dope whose temperature was adjusted to be 30.degree. C.
was uniformly cast on an endless stainless steel belt (support)
such that the film thickness after drying became 100 .mu.m.
[0351] Immediately after casting, the dope film (web) on the belt
was dried by being exposed to hot air with a temperature of
100.degree. C. Then, 120 seconds after casting, the film was peeled
at a peeling tension of 150 N/m and dried while being transported
by a large number of rolls at a transport tension of 100 N/m. The
temperature of the endless stainless steel belt in the peeling
portion was set to be 10.degree. C. The amount of the residual
solvent at the time of peeling was 100% by mass.
[0352] The film was dried by being transported for 5 minutes within
a first drying zone set to be 80.degree. C. and then for 10 minutes
within a second drying zone set to be 120.degree. C. After being
dried, the film was wound in the form of a roll, thereby obtaining
a TAC film having a film width of 1.5 m, a rolled length of 2,000
m, and a film thickness of 100 .mu.m. The amount of the residual
solvent at the time of winding was 0.3% by mass.
[Fluorine-Based Film]
[0353] As a fluorine-based film, a product named "F-CLEAN
(registered trademark) SHIZENKORYUTEKI" manufactured by AGC
Green-Tech Co., Ltd was used.
[Microporous Polyolefin (Microporous PO) Film]
[0354] As a microporous PO film, a product named "KAITEKIKUKAN"
manufactured by Mitsubishi Plastics Agri Dream Co., Ltd was
used.
Examples 3-1 to 3-5, Comparative Examples 3-1 to 3-4, and Reference
Examples 1 and 2
<Preparation of Agricultural Greenhouse>
[0355] In Miyanodai, Minamiashigara-shi, a framework with a size of
6.0 m.times.9.0 m.times.4.0 m (height) was set up, and each of the
covering films shown in the following Table 6 was spread over the
frame, thereby preparing an agricultural greenhouse.
[0356] Then, on the inside of the prepared agricultural greenhouse,
a framework with a size of 5.8 m.times.8.8 m.times.3.8 m (height)
was set up, and each of the lining films shown in the following
Table 6 was spread over the frame, thereby preparing an
agricultural greenhouse.
[0357] In the following Table 6, the aspect in which
"TAC/fluorine-based" is described as the lining film means that a
TAC film was used for the roof portion of the lining film and a
fluorine-based film was used for the wall surface portion of the
lining film as shown in the following Table 6.
[0358] In Reference Examples 1 and 2, the agricultural greenhouse
was used over which only the covering film was spread without using
the lining film.
[0359] For the prepared agricultural greenhouse, the water vapor
permeability and the light transmittance of the lining film and the
covering film were measured and evaluated by the following methods.
The results are shown in the following Table 6.
[0360] Furthermore, for the prepared agricultural greenhouse, at
08:00 A.M on a clear day in November 2014, whether or not the dew
condensation occurred on the inside of the lining film was visually
checked, and at 18:00 after sunset on the same day, the internal
temperature and the internal relative humidity of the agricultural
greenhouse were measured. The results are also shown in the
following Table 6.
<Water Vapor Permeability>
[0361] For each film, according to the technique described in JIS Z
0208:1976 "Testing methods for determination of the water vapor
permeability of moisture-proof packaging materials (cup method)",
the amount (g/m.sup.2/24 h) of water vapor passing through the film
for 24 hours under the conditions of a temperature of 40.degree. C.
and a relative humidity of 90% was measured.
[0362] In the following Table 6, for Examples 3-3 and 3-5, the
water vapor permeability of the TAC film used for the roof portion
of the lining film is shown.
<Light Transmittance>
[0363] For each film, the transmittance at a visible region of 400
to 700 nm was measured using a spectrophotometer (manufactured by
Jasco Engineering and Sales, Inc.: V-560), and the average thereof
was calculated.
[0364] In a case where the product of the average light
transmittance of the lining film and the average light
transmittance of the covering film was equal to or higher than 80%,
the light transmittance of the agricultural greenhouse was regarded
as being high and was evaluated to be "A". In a case where the
product was equal to or higher than 60% and less than 80%, the
light transmittance of the agricultural greenhouse was regarded as
being slightly low and was evaluated to be "B". In a case where the
product was less than 60%, the light transmittance of the
agricultural greenhouse was regarded as being low and was evaluated
to be "C".
TABLE-US-00010 TABLE 6 Covering film Lining film Water Water
Portion Type of vapor vapor Wall film permeability Thickness
permeability Thickness Roof surface Table 6 Covering Lining
g/m.sup.2/24 h .mu.m g/m.sup.2/24 h .mu.m portion portion Example
TAC TAC 1,000 100 1,000 100 TAC TAC 3-1 Example 3-2 TAC TAC 1,000
100 1,000 100 TAC TAC Example 3-3 TAC TAC/fluorine- 1,000 100 1,000
100 TAC Fluorine- based (roofportion) based Example 3-4 Fluorrine-
TAC 20 100 1,000 100 TAC TAC based Example 3-5 Fluorrine-
TAC/fluorine- 20 100 1,000 100 TAC Fluorine- based based (roof
portion) based Comparative Fluorrine- Fluorine- 20 100 20 100
Fluorine- Fluorine- Example 3-1 based based based based Comparative
Fluorrine- Fluorine- 20 100 20 100 Fluorine- Fluorine- Example 3-2
based based based based Comparative Fluorrine- TAC 20 100 1,000 100
TAC TAC Example 3-3 based Comparative Fluorrine- Microporous 20 100
1,200 100 Microporous Microporous Example 3-4 based PO PO PO
Reference TAC -- 1,000 100 -- -- -- -- Example 1 Reference
Fluorrine- -- 20 100 -- -- -- -- Example 2 based Internal
environment of greenhouse Relative Ventilation Dew Light
Temperature humidity means condensation transmittance .degree. C. %
Example 3-1 Covering film, Not occurred A 15 80 ventilation fan
Example 3-2 Covering Not occurred A 18 83 film Example 3-3 Covering
film, Not occurred A 16 81 ventilation fan Example 3-4 Ventilation
Not occurred A 15 85 fan Example 3-5 Ventilation Not occurred A 16
88 fan Comparative N/A Occurred B 18 99 Example 3-1 Comparative
Ventilation Occurred B 13 99 Example 3-2 fan Comparative N/A
Occurred A 17 90 Example 3-3 Comparative Ventilation Occurred C 14
85 Example 3-4 fan Reference Covering Not occurred A 10 85 Example
1 film Reference N/A Occurred B 10 99 Example 2
[0365] As shown in Table 6, it was understood that, in a case where
a fluorine-based film is used as the lining film, regardless of the
existence of ventilation means, dew condensation occurs, and the
light transmittance is reduced (Comparative Examples 3-1 and
3-2).
[0366] Furthermore, it was understood that, in a case where a TAC
film having a water vapor permeability equal to or higher than 600
g/m.sup.2/24 h is used as the lining film, if the agricultural
greenhouse does not have ventilation means, the occurrence of dew
condensation cannot be inhibited (Comparative Example 3-3).
[0367] In addition, it was understood that, in a case where a
microporous PO film is used as the lining film in consideration of
JP2011-10590A, even if the agricultural greenhouse has ventilation
means, dew condensation occurs, and the light transmittance is
reduced (Comparative Example 3-4).
[0368] In contrast, it was understood that, in a case where a TAC
film having a water vapor permeability equal to or higher than 600
g/m.sup.2/24 h is used in at least a portion of the lining film,
and the agricultural greenhouse has ventilation means, the dew
condensation occurring on the inside of the lining film is
inhibited, and the light transmittance increases (Examples 3-1 to
3-5)
[0369] Particularly, it was understood that, in Examples 3-1 to 3-3
in which a TAC film is also used as the covering film, the covering
film itself functions as ventilation means, and accordingly,
regardless of the existence of a ventilation fan, the internal
relative humidity of the greenhouse can be reduced.
[Fourth Aspect]
[0370] Hereinafter, the fourth aspect of the present invention will
be more specifically described based on examples. The materials and
the amount thereof used, the proportion of the materials, the
treatment content, the treatment procedure, and the like shown in
the following examples can be appropriately changed within a scope
that does not depart from the gist of the present invention.
Accordingly, the scope of the present invention is not limited to
the following examples.
[0371] <Synthesis of plasticizer>
[0372] By the following method, as plasticizers used in Examples
4-1 to 4-26, polyether esters and polyethers were synthesized.
Regarding each of the synthesized polyether esters, the number of
polymerized monomers (n), the number of polymerized monomers (p),
and the terminal (R.sup.3) in Formula (A) described above are shown
in the following Tables 7 and 8. Regarding each of the synthesized
polyethers, the number of polymerized monomers (m), the terminal
(R.sup.5), and the terminal (R.sup.6) in Formula (B) described
above are shown in the following Tables 7 and 8.
(Plasticizer A--Used in Example 4-1)
[0373] Adipic acid and monoethylene glycol were polyesterified by a
thermal melting condensation method, thereby synthesizing a
polyether ester.
(Plasticizer B--Used in Example 4-2)
[0374] Adipic acid and diethylene glycol were polyesterified by a
thermal melting condensation method, thereby synthesizing a
polyether ester.
(Plasticizer C--Used in Example 4-3)
[0375] Adipic acid and triethylene glycol were polyesterified by a
thermal melting condensation method, thereby synthesizing a
polyether ester.
(Plasticizer D--Used in Example 4-4)
[0376] Adipic acid and tetraethylene glycol were polyesterified by
a thermal melting condensation method, thereby synthesizing a
polyether ester.
(Plasticizer E--Used in Example 4-5)
[0377] Adipic acid and triethylene glycol were polyesterified by a
thermal melting condensation method, thereby synthesizing a
polyether ester.
(Plasticizer F--Used in Example 4-6)
[0378] Adipic acid and triethylene glycol were polyesterified by a
thermal melting condensation method, thereby synthesizing a
polyether ester.
(Plasticizer G--Used in Example 4-7)
[0379] Adipic acid and triethylene glycol were polyesterified by a
thermal melting condensation method, thereby synthesizing a
polyether ester.
(Plasticizer H--Used in Example 4-8)
[0380] Succinic acid and triethylene glycol were polyesterified by
a thermal melting condensation method, thereby synthesizing a
polyether ester.
(Plasticizer I--Used in Example 4-9)
[0381] Succinic acid and tetraethylene glycol were polyesterified
by a thermal melting condensation method, thereby synthesizing a
polyether ester.
(Plasticizer J--Used in Example 4-10)
[0382] Succinic acid and tetraethylene glycol were polyesterified
by a thermal melting condensation method, thereby synthesizing a
polyether ester.
(Plasticizer K--Used in Example 4-11)
[0383] Glutaric acid and triethylene glycol were polyesterified by
a thermal melting condensation method, thereby synthesizing a
polyether ester.
(Plasticizer L--Used in Example 4-12)
[0384] Adipic acid and 1,2-propylene glycol were polyesterified by
a thermal melting condensation method, thereby synthesizing a
polyether ester.
(Plasticizer M--Used in Example 4-13)
[0385] Adipic acid and tri(1,2-propylene glycol) were
polyesterified by a thermal melting condensation method, thereby
synthesizing a polyether ester.
(Plasticizer N--Used in Example 4-14)
[0386] Adipic acid and 1,2-butylene glycol were polyesterified by a
thermal melting condensation method, thereby synthesizing a
polyether ester.
(Plasticizer O--Used in Example 4-15)
[0387] Adipic acid and monoethylene glycol were polyesterified by a
thermal melting condensation method, thereby synthesizing a
polyether ester.
(Plasticizer P--Used in Example 4-16)
[0388] Adipic acid and monoethylene glycol were polyesterified by a
thermal melting condensation method, thereby synthesizing a
polyether ester.
(Plasticizer Q--Used in Example 4-17)
[0389] Ethylene oxide was sequentially reacted three times with
phenol by ring-opening addition, thereby synthesizing a polyether
as shown in the following scheme.
##STR00012##
(Plasticizer R--Used in Example 4-18)
[0390] Ethylene oxide was sequentially reacted twice with phenol by
ring-opening addition, thereby synthesizing a polyether.
(Plasticizer S--Used in Example 4-19)
[0391] Ethylene oxide was sequentially reacted twice with
hydroxyethyl methacrylate by ring-opening addition, thereby
synthesizing a polyether as shown in the following scheme.
##STR00013##
(Plasticizer T--Used in Example 4-20)
[0392] Propylene oxide was sequentially reacted 8 times with
hydroxyethyl methacrylate by ring-opening addition, thereby
synthesizing a polyether.
(Plasticizer U--Used in Example 4-21)
[0393] Adipic acid and triethylene glycol were polyesterified by a
thermal melting condensation method, thereby synthesizing a
polyether ester.
(Plasticizer V--Used in Example 4-22)
[0394] Adipic acid and diethylene glycol were polyesterified by a
thermal melting condensation method, thereby synthesizing a
polyether ester.
(Plasticizer W--Used in Example 4-23)
[0395] Succinc acid, monoethylene glycol, and tetraethylene glycol
were polyesterified by a thermal melting condensation method,
thereby synthesizing a polyether ester.
(Plasticizer X--Used in Example 4-24)
[0396] Adipic acid, monoethylene glycol, and tetraethylene glycol
were polyesterified by a thermal melting condensation method,
thereby synthesizing a polyether ester.
(Plasticizer Y--Used in Example 4-25)
[0397] Adipic acid, 1,2-propylene glycol, and tetraethylene glycol
were polyesterified by a thermal melting condensation method,
thereby synthesizing a polyether ester.
(Plasticizer Z--Used in Example 4-26)
[0398] Adipic acid, 1,3-butanediol, and tetraethylene glycol were
polyesterified by a thermal melting condensation method, thereby
synthesizing a polyether ester.
Examples 4-1 to 4-26
<Preparation of Dope>
[0399] The following composition was put into a mixing tank and
stirred such that each component dissolved, thereby preparing a
cellulose acetate solution.
TABLE-US-00011 Cellulose acylate 100 parts by mass (degree of
acetyl group substitution: 2.86, viscosity average polymerization
degree: 320) Plasticizers shown in the following Tables 7 and 8
Amount shown in each table (parts by mass) Silica particle
dispersion (average particle 1.3 parts by mass size: 16 nm)
"AEROSIL R972" manufactured by NIPPON AEROSIL CO., LTD Methylene
chloride 635 parts by mass Methanol 1.3 parts by mass
<Preparation of Film>
[0400] The dope whose temperature was adjusted to be 30.degree. C.
was uniformly cast on an endless stainless steel belt (support)
such that the film thickness after drying became 100 .mu.m.
[0401] Immediately after casting, the dope film (web) on the belt
was dried by being exposed to hot air with a temperature of
100.degree. C. Then, 120 seconds after casting, the film was peeled
at a peeling tension of 150 N/m and dried while being transported
by a large number of rolls at a transport tension of 100 N/m. The
temperature of the endless stainless steel belt in the peeling
portion was set to be 10.degree. C. The amount of the residual
solvent at the time of peeling was 100% by mass.
[0402] The film was dried by being transported for 5 minutes within
a first drying zone set to be 80.degree. C. and then for 10 minutes
within a second drying zone set to be 120.degree. C. After being
dried, the film was wound into the form of a roll, thereby
preparing a film for an agricultural greenhouse having a film width
of 1.5 m, a rolled length of 2,000 m, and a film thickness of 80
.mu.m. The amount of the residual solvent at the time of winding
was 0.3% by mass.
Comparative Example 4-1
[0403] A film for an agricultural greenhouse was prepared by the
same method as in Example 4-1, except that the plasticizer A was
not blended.
Comparative Example 4-2
[0404] A film for an agricultural greenhouse was prepared by the
same method as in Example 4-1, except that, instead of the
plasticizer A, a dope was used which was blended with a total of 15
parts by mass of triphenyl phosphate (TPP) and biphenyl diphenyl
phosphate (BDP) at a mass ratio of 2:1.
Comparative Example 4-3
[0405] As a film for an agricultural greenhouse, a PET film product
named "SIXLIGHT CLEAN" manufactured by Mitsubishi Plastics Agri
Dream Co., Ltd was used.
Comparative Example 4-4
[0406] As a film for an agricultural greenhouse, a vinyl chloride
film product named "NOBI-ACE-MIRAI" manufactured by Mitsubishi
Plastics Agri Dream Co., Ltd was used.
Comparative Example 4-5
[0407] As a film for an agricultural greenhouse, a PO film product
named "SKY COAT 5" manufactured by C. I. KASEI CO., LTD was
used.
Comparative Example 4-6
[0408] As a film for an agricultural greenhouse, a fluorine-based
film product named "F-CLEAN SHIZENKORYUTEKI" manufactured by AGC
Green-Tech Co., Ltd was used.
[0409] For each of the prepared films for an agricultural
greenhouse and the commercially available products used as the
films, water vapor permeability, modulus of elasticity, elongation
rate, light transmittance, drip-proofness, and workability were
measured and evaluated by the following methods. The results are
shown in the following Tables 7 and 8.
[0410] For each of the films for an agricultural greenhouse
prepared in Examples 4-5, 4-8, and 4-17 to 4-26, an elution rate
was measured by the following method. The results are shown in the
following Table 8.
<Water Vapor Permeability>
[0411] For each of the prepared films for an agricultural
greenhouse, according to the technique described in JIS Z 0208:1976
"Testing methods for determination of the water vapor permeation
(cup method) of moisture-proof packing materials", the amount of
water vapor (g/m.sup.2/24 h) passing through the film for 24 hours
under the conditions of a temperature of 40.degree. C. and a
relative humidity of 90% was measured.
<Modulus of Elasticity>
[0412] From each of the prepared films for an agricultural
greenhouse, a total of 8 samples having a length of 150 mm in a
measurement direction and a width of 15 mm were prepared by varying
the orientation of cutting in the measurement direction by
45.degree..
[0413] Then, each sample was left as it was for 24 hours in an
environment with a temperature of 25.degree. C. and a relative
humidity of 60% and then immediately stretched at an inter-chuck
distance of 100 mm and a tensile rate of 200 mm/min in an
atmosphere with a temperature of 25.degree. C. and a relative
humidity of 60% by using a tensile tester "STROGRAPH" manufactured
by A&D Company, Limited. The stress applied at the time when
the sample was stretched by 0.1% and at the time when the sample
was stretched by 0.5% was measured, and from the slope thereof, the
modulus of elasticity was calculated. The average thereof was
calculated as a modulus of elasticity.
<Elongation Rate>
[0414] Each sample for which the modulus of elasticity was
calculated was left as it was for 24 hours in an environment with a
temperature of 25.degree. C. and a relative humidity of 60% and
then immediately stretched at an inter-chuck distance of 100 mm and
a tensile rate of 200 mm/min in the atmosphere with a relative
humidity of 60% at 25.degree. C. by using a tensile tester
"STROGRAPH" manufactured by A&D Company, Limited. From the
amounts of the elongation strain applied at the time when the
samples were broken, the elongation rates were calculated, and the
average thereof was calculated as the elongation rate.
<Light Transmittance>
[0415] For each of the prepared films for an agricultural
greenhouse, the transmittance at a visible region of 400 to 700 nm
was measured using a spectrophotometer (manufactured by Jasco
Engineering and Sales, Inc.: V-560), and the average thereof was
calculated.
[0416] As a result of the measurement, in a case where the average
light transmittance was equal to or higher than 90%, the film was
evaluated to be "A". In a case where the average light
transmittance was equal to or higher than 80% and less than 90%,
the film was evaluated to be "B". In a case where the average light
transmittance was less than 80%, the film was evaluated to be
"C".
<Drip-Proofness>
[0417] A hot-water bath with a temperature of 40.degree. C. was
sealed with each of the prepared films for an agricultural
greenhouse and cooled to 25.degree. C. so as to forcedly cause dew
condensation, and then the time taken for dews to disappear was
measured.
[0418] In a case where the time taken for dews to disappear was
less than 3 hours, the film was evaluated to be "A". In a case
where the time was equal to or longer than 3 hours and less than 5
hours, the film was evaluated to be "B". In a case where the time
was equal to or longer than 5 hours and less than 12 hours, the
film was evaluated to be "C". In a case where the time was equal to
or longer than 12 hours, the film was evaluated to be "D".
<Workability>
[0419] By using each of the prepared films for an agricultural
greenhouse, an agricultural greenhouse was installed, and the way
each film was broken at this time was observed.
[0420] In a case where the film was not broken, the film was
evaluated to be "A". In a case where the film was found to be
slightly broken at 1 or 2 sites, the film was regarded as being
unproblematic for practical use and evaluated to be "B". In a case
where the film was found to be seriously broken was evaluated to be
"C".
<Elution Rate>
[0421] For each of the films for an agricultural greenhouse
prepared in Examples 4-5, 4-8, and 4-17 to 4-26, the mass change
that occurred before and after the films were immersed into water
for 16 hours was measured, and the proportion of the mass of the
film eluted into water was calculated as an elution rate.
[0422] Specifically, each of the prepared films for an agricultural
greenhouse was dried for 8 hours at 40.degree. C. under pressure
reduction conditions, and then the mass (mass before immersion)
thereof was measured. Thereafter, each of the films for an
agricultural greenhouse was immersed into water with a temperature
of 15.degree. C. for 16 hours and then dried for 8 hours at
40.degree. C. under the same pressure reduction conditions, and
then the mass (mass after immersion) thereof was measured.
[0423] Then, from the following Equation (I), the elution rate was
calculated.
Elution rate=[(mass before immersion-mass after immersion)/mass
before immersion].times.100 (I)
[0424] Herein, the plasticizer was added in an amount of 60 parts
by mass with respect to 100 parts by mass of the triacetyl
cellulose (TAC), and the proportion of the plasticizer contained
was 37.5% by mass. Accordingly, it is understood that, in Example 5
in which the elution rate is 36%, most of the plasticizer is
eluted.
TABLE-US-00012 TABLE 7 Plasticizer (polyether ester) Diol Number of
Dicarboxylic Number of polymerized Amount Resin acid polymerized
monomers Terminal added (parts Table 7 material No. Type Type
monomers (n) (p) (R.sup.3) by mass) Example 4-1 TAC A Adipic
Monoethylene 1 1 Hydrogen 40 acid glycol atom Example 4-2 TAC B
Adipic Diethylene 2 1 Hydrogen 40 acid glycol atom Example 4-3 TAC
C Adipic Triethylene 3 1 Methyl 40 acid glycol Example 4-4 TAC D
Adipic Tetraethylene 4 1 Methyl 40 acid glycol Example 4-5 TAC E
Adipic Triethylene 3 1 Methyl 60 acid glycol Example 4-6 TAC F
Adipic Triethylene 3 1 Hydrogen 40 acid glycol atom Example 4-7 TAC
G Adipic Triethylene 3 1 Acetyl 40 acid glycol Example 4-8 TAC H
Succinic Triethylene 3 1 Methyl 60 acid glycol Example 4-9 TAC I
Succinic Tetraethylene 4 1 Methyl 60 acid glycol Example 4-10 TAC J
Succinic Tetraethylene 4 1 Methyl 20 acid glycol Example 4-11 TAC K
Glutaric Triethylene 3 1 Methyl 40 acid glycol Example 4-12 TAC L
Adipic 1,2-propylene 1 1 Methyl 40 acid glycol Example 4-13 TAC M
Adipic Tri(1,2-propylene 3 1 Methyl 40 acid glycol) Example 4-14
TAC N Adipic 1,2-butylene 1 1 Methyl 40 acid glycol Example 4-15
TAC O Adipic Monoethylene 1 2 Hydrogen 40 acid glycol atom Example
4-16 TAC P Adipic Monoethylene 1 3 Hydrogen 40 acid glycol atom
Water vapor Modulus permeability of Elongation Thickness
(g/m.sup.2/ elasticity rate Light (.mu.m) 24 h) (GPa) (%)
transmittance Drip-proofness Workability Example 4-1 80 600 2.1 49
A C B Example 4-2 80 660 2.4 42 A C B Example 4-3 80 1,010 1.9 50 A
A A Example 4-4 80 1,090 2.2 45 A A B Example 4-5 80 1,440 0.8 65 A
A A Example 4-6 80 930 2.0 50 A B B Example 4-7 80 640 2.1 50 A C B
Example 4-8 80 1,450 0.7 48 A A A Example 4-9 80 1,430 0.8 56 A A A
Example 4-10 80 752 3.0 40 A C B Example 4-11 80 1,050 1.8 53 A A A
Example 4-12 80 650 1.1 55 A C A Example 4-13 80 980 1.6 50 A B A
Example 4-14 80 700 1.0 60 A C A Example 4-15 80 950 2.4 38 A B B
Example 4-16 80 880 2.7 36 A B B Plasticizer (polyether) Number of
Amount Resin Terminal Terminal polymerized monomers added (parts
material No. (R.sup.5) (R.sup.6) (m) by mass) Example 4-17 TAC Q
Phenyl Hydrogen 3 60 group atom Example 4-18 TAC R Phenyl Hydrogen
2 60 group atom Example 4-19 TAC S Methacryloyl Hydrogen 3 60 group
atom Example 4-20 TAC T Methacryloyl Hydrogen 9 60 group atom
Comparative TAC -- -- -- -- -- -- 0 Example 4-1 Comparative TAC
TPP/BDP 15 Example 4-2 Comparative PET -- -- Example 4-3
Comparative Vinyl -- -- Example 4-4 chloride Comparative PO -- --
Example 4-5 Comparative Fluorine- -- -- Example 4-6 based Water
Modulus vapor of Elongation Thickness permeability elasticity rate
Light (.mu.m) (g/m.sup.2/24 h) (GPa) (%) transmittance
Drip-proofness Workability Example 4-17 80 1,850 1.7 60 A A A
Example 4-18 80 860 2.9 36 A B B Example 4-19 80 2,660 1.2 47 A A A
Example 4-20 80 1,360 1.8 44 A A A Comparative 80 970 4.2 21 A B C
Example 4-1 Comparative 80 450 4.4 20 A C C Example 4-2 Comparative
150 23 3.7 62 B D B Example 4-3 Comparative 100 50 0.0 314 B D A
Example 4-4 Comparative 100 3 0.1 >560 C D A Example 4-5
Comparative 100 20 0.9 477 B D A Example 4-6
TABLE-US-00013 TABLE 81 Plasticizer (polyether ester) Diol
Dicarboxylic Number of Number of Amount Resin acid polymerized
polymerized Terminal added (parts Table 8 material No. Type Type
monomers (n) monomers (p) (R.sup.3) by mass) Example TAC E Adipic
Ethylene glycol 3 1 Methyl 60 4-5 acid Example TAC H Succinic
Ethylene glycol 3 1 Methyl 60 4-8 acid Example TAC U Adipic
Ethylene glycol 3 6 Methyl 60 4-21 acid Example TAC V Adipic
Ethylene glycol 2 6 Methyl 60 4-22 acid Example TAC W Succinic
Monoethylene glycol 1 9 Hydrogen 60 4-23 acid Tetraethylene glycol
4 atom Example TAC X Adipic Monoethylene glycol 1 9 Hydrogen 60
4-24 acid Tetraethylene glycol 4 atom Example TAC Y Adipic
1,2-Propylene glycol 1 9 Hydrogen 60 4-25 acid Tetraethylene glycol
4 atom Example TAC Z Adipic 1,3-butanediol 1 9 Hydrogen 60 4-26
acid Tetraethylene glycol 4 atom Water vapor Modulus permeability
of Elongation Elution Thickness (g/m.sup.2/ elasticity rate rate
Light Table 8 (.mu.m) 24h) (GPa) (%) (%) transmittance
Drip-proofness Workability Example 80 1,440 0.8 65 36 A A A 4-5
Example 80 1,450 0.7 48 32 A A A 4-8 Example 80 820 1.4 55 13 A B A
4-21 Example 80 710 1.4 54 5.4 A B A 4-22 Example 80 820 1.4 43 9.5
A B A 4-23 Example 80 1,100 1.2 56 7.5 A A A 4-24 Example 80 1,050
1.4 43 8.1 A A A 4-25 Example 80 1,028 1.7 42 6.2 A A A 4-26
Plasticizer (polyether) Amount added Number of (parts Resin
Terminal Terminal polymerized by material No. (R.sup.5) (R.sup.6)
monomers (m) mass) Example TAC Q Phenyl Hydrogen 3 60 4-17 group
atom Example TAC R Phenyl Hydrogen 2 60 4-18 group atom Example TAC
S Methacryloyl Hydrogen 3 60 4-19 group atom Example TAC T
Methacryloyl Hydrogen 9 60 4-20 group atom Water vapor per- Modulus
Elonga- meability of tion Elution Light Thickness (g/m.sup.2/
elasticity rate rate transmit- Drip- Work- (.mu.m) 24h) (GPa) (%)
(%) tance proofness ability Example 80 1,850 1.7 60 14 A A A 4-17
Example 80 860 2.9 36 29 A B B 4-18 Example 80 2,660 1.2 47 8.2 A A
A 4-19 Example 80 1,360 1.8 44 31 A A A 4-20
[0425] From the above results, it was understood that the film
which has a water vapor permeability equal to or higher than 600
g/m.sup.2/24 h and a modulus of elasticity equal to or greater than
3.0 GPa has poor workability even though the film contains a
cellulose acylate resin (Comparative Example 4-1).
[0426] Similarly, it was understood that the film which has a water
vapor permeability of less than 600 g/m.sup.2/24 h and a modulus of
elasticity equal to or greater than 3.0 GPa has poor workability
even though the film contains a cellulose acylate resin
(Comparative Example 4-2).
[0427] In contrast, it was understood that all the films using a
resin other than a cellulose acylate resin have low water vapor
permeability and poor drip-proofness (Comparative Examples 4-3 to
4-6).
[0428] On the contrary, it was understood that all the films, which
contain a cellulose acylate resin and have a water vapor
permeability equal to or higher than 600 g/m.sup.2/24 h and a
modulus of elasticity of less than 3.0 GPa, have excellent
drip-proofness and workability (Examples 4-1 to 4-26).
[0429] Particularly, from the comparison of Example 4-3 and Example
4-6, it was understood that, in a case where the polyether ester
represented by Formula (A) described above is used as a
plasticizer, if the terminal R.sup.3 is an alkyl group,
drip-proofness and workability are further improved.
[0430] In addition, from the comparison of Example 4-9 and Example
4-10, it was understood that, if the content of the plasticizer is
30 to 60 parts by mass with respect to 100 parts by mass of the
cellulose acylate resin, drip-proofness and workability are further
improved.
[0431] Furthermore, from the comparison of Examples 4-5, 4-21, and
4-22, it was understood that the higher the degree of
polymerization of the plasticizer, the lower the elution rate.
[0432] Moreover, from the comparison of Examples 4-23 to 4-26, it
was understood that, in a case where the degree of polymerization
of the plasticizer is the same, the plasticizer synthesized using
adipic acid which is a dicarboxylic acid having a large number of
carbon atoms reduces the degree of elution.
EXPLANATION OF REFERENCES
[0433] 1: film
[0434] 2: frame
[0435] 10: agricultural greenhouse
[0436] 11: covering film
[0437] 12: lining film
[0438] 12a: roof portion of lining film
[0439] 12b: wall surface portion of lining film
[0440] 13: frame
[0441] 14: ventilation fan
[0442] 20: agricultural greenhouse
* * * * *