JP5469132B2 - Reefer container - Google Patents

Description

  The present invention relates to a reefer container.

  Conventionally, in containers for storing fresh food, fresh flowers, etc., in order to maintain freshness, adjusting the temperature and the oxygen concentration and the carbon dioxide concentration have been performed. As a method for adjusting the oxygen concentration and the carbon dioxide concentration, for example, MA (Modified Atmosphere) and CA (Controlled Atmosphere) are known.

  In the MA, oxygen or carbon dioxide is supplied into the container through a direct method of supplying outside air directly into the container for ventilation (see Patent Document 1) and a packaging material having a predetermined oxygen transmission rate and carbon dioxide transmission rate. There is an indirect method of supplying (see Patent Document 2), and the indirect method is called MA packaging. CA is a method for controlling the oxygen concentration and carbon dioxide concentration in a container using adsorption separation or membrane separation, and is called CA storage (see Patent Document 3).

JP 2008-50027 A JP-A-6-11235 Japanese Patent Laid-Open No. 3-85287

  Here, containers for storing fresh food, fresh flowers and the like are usually refrigerated or frozen in order to maintain freshness, and have a large temperature difference from the outside air. When the MA of Patent Documents 1 and 2 is applied to such a container, all the gas containing nitrogen in the container is replaced, so that the temperature in the container greatly fluctuates and the heat load for adjusting the temperature again Becomes larger.

  In addition, the optimal oxygen concentration and carbon dioxide concentration for maintaining freshness differ depending on the type of fresh food, fresh flowers, etc., but in the indirect method such as Patent Document 2, the gas permeation rate depends on the type of packaging material. It is necessary to change the packaging material according to the kind of fresh food or fresh flowers. Furthermore, in CA storage such as Patent Document 3, a pressurization pump and a depressurization pump are used to obtain a desired gas concentration, which increases the running cost and complicates the apparatus.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a container that can adjust a desired gas concentration with a simple configuration and that can reduce the thermal load during gas concentration adjustment.

The present invention is a reefer container in which ventilation is performed through a ventilation filter, wherein the ventilation filter is a polymer obtained by polymerizing a monomer composition containing a monomer represented by the following formula (1). A reefer container comprising an asymmetric membrane formed of a material is provided. The “reefer container” refers to a container for transporting fresh foods, frozen foods, fresh flowers, chemical products that require low-temperature transport, pharmaceuticals, electronic parts, films, artworks, and the like. The reefer container of the present invention is particularly suitable for applications that require ventilation in the container during transportation, for example, fresh food such as fruits and vegetables and fresh flowers.

(In the formula, R ¹ is independently an alkyl group having 1 to 12 carbon atoms and / or an aryl group having 6 to 10 carbon atoms, and X is a group represented by the following formula (i) and / or the following formula: (Ii) is a group represented by (ii), a is an integer of 1 to 3, and b is an integer of 0 to 2.

(R ² is each independently an alkyl group having 1 to 12 carbon atoms, d is an integer of 1 to 5, and c is an integer of 3 to 5.)

  According to such a reefer container, the desired gas concentration can be adjusted with a simple configuration, and the heat load during the gas concentration adjustment can be reduced. The asymmetric membrane refers to a membrane having a porous layer and a dense layer adjacent thereto, and the asymmetric membrane preferably has nanometer-size or micrometer-size pores on the dense layer surface.

  The reason why the above effect can be obtained by the reefer container of the present invention is not necessarily clear, but the present inventors consider as follows.

  That is, as described above, when the conventional direct method is applied, since all the gas containing nitrogen in the container is replaced, the temperature in the container greatly fluctuates, and the heat load for adjusting the temperature again Becomes larger. On the other hand, according to the reefer container of the present invention, by using the above-described ventilation filter, only necessary components can be exchanged inside and outside the container, and it is possible to suppress intake and extraction of gas that does not need to be exchanged. We believe that it is one factor that can achieve the above-mentioned effects.

  The polymer material is preferably an addition polymer obtained by addition polymerization of a monomer composition containing the monomer represented by the formula (1). Thereby, the effect by this invention is show | played more notably.

The ratio of the oxygen permeability coefficient P (O ₂ ) and the carbon dioxide permeability coefficient P (CO ₂ ) of the asymmetric membrane under the condition of 23 ± 2 ° C. and no pressure difference between the membranes satisfies the following formula (3). preferable. Thereby, the effect by this invention is show | played especially notably.
1.0 <P (O ₂ ) / P (CO ₂ ) <1.70 (3)

  The reefer container is present in a casing in which the temperature of the inside air existing inside is adjusted, gas concentration detection means for detecting a specific type of gas concentration in the casing, an outside air flow path through which outside air flows, and the casing. A flow path forming member that forms an internal air flow path through which the internal air flows, and an external air flow path and an internal air flow path so that one surface is in contact with the external air in the external air flow path and the other surface is in contact with the internal air in the internal air flow path A ventilation filter disposed at the boundary of the air flow, an air blowing means for generating at least one of an outside air flow in the outside air flow path and an inside air flow in the inside air flow path, and a control means for performing air blowing control by the air blowing means. The control means can be configured to perform air flow control of at least one of the outside air and the inside air by the air blowing means based on the gas concentration detected by the gas concentration detecting means.

  The reefer container is provided with an inside air circulation blower for circulating the inside air in the housing, and the air blowing means for generating the inside air flow in the inside air flow path uses the inside air flow generated by the inside air circulation blower as the inside air flow. By introducing into the path, the flow of the inside air in the inside air flow path may be generated.

  In the reefer container, the air blowing means for generating the flow of the outside air in the outside air flow path and the flow of the inside air in the inside air flow path includes a first blower fan provided in the inside air flow path or the outside air flow path, and a first blower A second blower fan provided in a flow path different from the fan, drive means for rotationally driving the first blower fan, and a power transmission member for transmitting the rotational driving force of the drive means to the second blower fan; May be provided.

  According to the present invention, it is possible to provide a reefer container that can adjust a desired gas concentration with a simple configuration and that can reduce a thermal load during gas concentration adjustment. Furthermore, according to the reefer container of the present invention, entry of fine particles such as dust and dust from outside the container can be prevented.

It is a conceptual diagram which shows the structure of the container 1 of 1st Embodiment of this invention. 4 is a cross-sectional view showing the flow of outside air in the outside air flow path 22 and the flow of inside air in the inside air flow path 23. It is a conceptual diagram which shows the structure of the container 1 of 2nd Embodiment of this invention. It is a conceptual diagram which shows an example of the cross-sectional structure of the filter unit for ventilation 20 of 3rd Embodiment of this invention. It is a conceptual diagram which shows the other example of the cross-sectional structure of the filter unit 20 for ventilation of 3rd Embodiment of this invention. It is a conceptual diagram which shows the structure of the container 1 of 4th Embodiment of this invention. It is a conceptual diagram which shows the structure of the container 1 of 5th Embodiment of this invention. It is a conceptual diagram which shows the structure of the container 1 of 6th Embodiment of this invention. It is sectional drawing which shows one Embodiment of an asymmetric membrane. It is sectional drawing which shows one Embodiment of an asymmetric membrane structure. It is sectional drawing which shows one Embodiment of an asymmetric membrane structure. 10 is a SEM image of an asymmetric membrane of Example 6. 10 is a SEM image of a water surface development film of Comparative Example 3. It is the schematic of the isobaric gas permeability measuring apparatus for measuring the gas permeability under an equal pressure. It is the schematic of the gas-permeability evaluation apparatus for measuring the gas-permeability under differential pressure. It is the schematic of the isobaric gas permeability measuring apparatus for measuring water vapor permeability. It is the schematic of the measuring apparatus for measuring microparticle blocking | blocking property.

  Hereinafter, the present invention will be described in detail with reference to the drawings depending on cases, but the present invention is not limited thereto.

(Reefer container)
The reefer container of the present embodiment is ventilated through a ventilation filter described later. For example, a part of the housing of the container can be replaced with a ventilation filter. Ventilation through the ventilation filter can be performed, for example, by using a difference in concentration between the inside air and the outside air or by creating a pressure difference between the inside air and the outside air. As means for performing ventilation through the ventilation filter, conventionally known means may be applied, or the following configuration may be applied.

<Configuration>
A case in which the temperature of the inside air present inside is adjusted, a gas concentration detection means for detecting a specific type of gas concentration in the case, an outside air flow path through which outside air flows, and inside air in which the inside air flows A flow path forming member that forms an air flow path, and the external air flow path and the internal air flow path such that one surface is in contact with the external air in the external air flow path and the other surface is in contact with the internal air in the internal air flow path A ventilation filter disposed at the boundary between the air flow, an air blowing means for generating at least one of an outside air flow in the outside air flow path and an inside air flow in the inside air flow path, and a control means for performing air flow control by the air blowing means. The reefer container includes: a control unit that controls at least one of the outside air and the inside air by the blowing unit based on the gas concentration detected by the gas concentration detecting unit.

  Hereinafter, a more detailed embodiment of the reefer container of the present invention having the above configuration will be described. In addition, although the accommodation accommodated in a reefer container is not specifically limited, In this embodiment, it demonstrates taking the fruit and vegetables which are suitable accommodations as an example.

[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a conceptual diagram showing a configuration of a reefer container 1 (hereinafter also simply referred to as “container 1”) according to the first embodiment.

  As shown in FIG. 1, the container 1 includes a housing 10 that can accommodate fruits and vegetables. The casing 10 of the present embodiment is configured as a refrigerator, a freezer or a freezing container for storing fruits and vegetables, and although not shown, an air conditioner for adjusting the inside air to a desired temperature is provided. The air conditioner can use a well-known refrigeration cycle for cooling the air-conditioned air, and can use a well-known heater (such as an electric type or a combustion type) for heating the air-conditioned air.

The case 10 is provided with an inside air circulation blower 11 for circulating the inside air throughout the inside of the case 10. Further, the housing 10 includes an O ₂ sensor 12 for detecting the oxygen concentration in the inside air, a CO ₂ sensor 13 for detecting the carbon dioxide concentration in the inside air, and a humidity sensor for detecting the humidity in the inside air. 14 is provided.

  The housing 10 is provided with a ventilation filter unit 20. The ventilation filter unit 20 is provided with a flow path forming member 21 that forms an external air flow path 22 and an internal air flow path 23. The flow path forming member 21 is provided so as to straddle the outside and the inside of the housing 10 with the wall surface of the housing 10 as a boundary. A ventilation filter 24 is provided at the boundary between the outside air passage 22 and the inside air passage 23. That is, a part of the wall surface of the housing 10 is replaced with the ventilation filter 24. In the outside air flow path 22, the outside air existing outside the housing 10 can flow along the surface of the ventilation filter 24, and in the inside air flow path 23, the inside air existing in the housing 10 is in the ventilation filter 24. Can flow along the surface.

  The ventilation filter 24 includes an asymmetric membrane described later. The asymmetric membrane may be used alone or as an asymmetric membrane structure supported by a support.

  The outside air flow path 22 is provided with an outside air circulation blower 25 for generating a flow of outside air. The inside air passage 23 is provided with an inside air circulation blower 26 for generating a flow of inside air. These blowers 25 and 26 have a compression ratio of less than 2 among fluid machines that give kinetic energy to gas or increase pressure, and are specifically fans and blowers. These blowers 25 and 26 include a blower fan and a motor that rotationally drives the blower fan.

  In the example shown in FIG. 1, the outside air in the outside air passage 22 flows from left to right, and the inside air in the inside air passage 23 flows from right to left. In addition, in the inside of the housing | casing 10, the flow through which internal air circulates with the internal air circulation fan 11, but when the internal air circulation fan 26 is not operating, the flow of internal air is almost in the internal air flow path 23. Does not occur.

  When the outside air circulation blower 25 or the inside air circulation blower 26 is not in operation, the gas stays near the surface of the ventilation filter 24, and the difference in gas concentration between the outside air and the inside air becomes small, and ventilation through the ventilation filter 24 is performed. It becomes difficult to progress. For this reason, by operating at least one of the outside air circulation blower 25 or the inside air circulation blower 26, the retention of gas near the surface of the ventilation filter 24 can be eliminated and ventilation can be promoted.

The container 1 is provided with a control unit 50. The control unit 50 is composed of a known microcomputer including a CPU, ROM, RAM and the like and its peripheral circuits, and performs various calculations and processing based on a control program stored in the ROM, and is connected to the output side. Control the operation of various devices. The controller 50 receives sensor signals from the O ₂ sensor 12, the CO ₂ sensor 13, and the humidity sensor 14. And the control part 50 outputs a control signal to the external air circulation fan 25 and the internal air circulation fan 26 based on these sensor signals, and performs ventilation control.

Since the fruits and vegetables breathe even after being accommodated in the housing 10, the inside of the housing 10 has a lower oxygen concentration and a higher carbon dioxide concentration than the atmosphere. It is known that fruits and vegetables can suppress respiration in a low oxygen concentration and high carbon dioxide concentration state for each type and can maintain freshness for a long period of time. On the other hand, if the oxygen concentration is excessively low, abnormalities in the metabolism of fruits and vegetables may occur, which may lead to a taste or odor or decay. In addition, the fruits and vegetables contain a large amount of moisture, and when they are housed in the housing 10, the moisture released from the fruits and vegetables often increases the relative humidity in the housing 10.
If the relative humidity in the housing 10 is too high, condensation occurs, and if it is too low, the fruits and vegetables are deflated. Both states are not preferable for maintaining the freshness of the fruits and vegetables. From the above, it is necessary to adjust the oxygen concentration, carbon dioxide concentration, and humidity in the housing 10 within desired ranges suitable for storage of fruits and vegetables.

The optimum oxygen concentration, carbon dioxide concentration, and humidity differ depending on the type of fruits and vegetables. For example, bananas are desirably stored within a range of 2 to 5% oxygen, 2 to 5% carbon dioxide, and 90 to 95% relative humidity. Strawberries are desirably stored within a range of 5 to 10% oxygen concentration, 15 to 20% carbon dioxide concentration, and 90 to 95% relative humidity. Mango is preferably stored in an oxygen concentration range of 3-5%, a carbon dioxide concentration of 5-10%, and a relative humidity of 85-90%. Therefore, in the present embodiment, the control unit 50 controls the air volume of the outside air circulation fan 25 and the inside air circulation fan 26 based on the sensor signals of the O ₂ sensor 12, the CO ₂ sensor 13, and the humidity sensor 14, so that the oxygen concentration Adjust the carbon dioxide concentration and relative humidity.

  Hereinafter, the ventilation control of the outside air circulation fan 25 and the inside air circulation fan 26 performed by the control unit 50 will be described. This control is executed according to a control program stored in the ROM or the like of the control unit 50.

  Here, an example is shown in which bananas are used as the objects to be stored, but the control method changes if the type of fruits or vegetables changes. Each of the oxygen concentration and the carbon dioxide concentration changes while satisfying the following formula.

Oxygen concentration + carbon dioxide concentration ≒ 21%
For example, when the oxygen concentration is 15%, the carbon dioxide concentration is 6%. On the other hand, the lower limit of oxygen concentration and the upper limit of carbon dioxide concentration that impede banana freshness maintenance are 1% and 7%, respectively (Source: Book title: GUIDE to FOOD TRANSPORT, 1. Controlled Atmosphere, Publisher: Mercantila Publishers). Therefore, the concentration range (oxygen concentration: 2-5%, carbon dioxide concentration: 2-5%) necessary for maintaining the freshness of bananas and the concentration range (oxygen concentration: less than 1%, carbon dioxide concentration: more than 7%) ) And the balance will determine which is the focus. In the case of bananas, control will be focused on the carbon dioxide concentration. Therefore, in the container 1 of this embodiment, it is necessary to set the carbon dioxide concentration to a concentration range of 2 to 5% and the oxygen concentration to 16 to 19%.

  Hereinafter, an example of the blower control of the blowers 25 and 26 when the banana is accommodated in the container 1 of the present embodiment will be described.

First, it is determined whether or not the carbon dioxide concentration detected by the CO ₂ sensor 13 has reached the upper limit of the desired range (5% for bananas). As a result, when the carbon dioxide concentration exceeds the upper limit of the desired range, the outside air circulation fan 25 and the inside air circulation fan 26 are operated to supply outside air and inside air to both surfaces of the ventilation filter 24. The air volume of the outside air circulation fan 25 and the inside air circulation fan 26 may be adjusted by adjusting the fan rotation output based on the carbon dioxide concentration detected by the CO ₂ sensor 13 (for example, ON-OFF control or PID control).

As a result, the carbon dioxide gas moves from the inside air having a high carbon dioxide concentration to the outside air having a low carbon dioxide concentration through the ventilation filter 24, and the carbon dioxide concentration in the housing 10 is lowered. At this time, with respect to other gases (O ₂ , H ₂ O) in which a concentration difference is generated between the outside air and the inside air, the outside air circulation fan 25 and the inside air circulation blower 26 are operated to activate the outside air and the inside air. The density difference between the two becomes smaller.

  After the outside air circulation blower 25 and the inside air circulation blower 26 are activated, it is determined whether or not the carbon dioxide concentration has reached the lower limit of the desired range (2% in the case of bananas). As a result, when the carbon dioxide concentration has reached the lower limit of the desired range, the operation of both or one of the outside air circulation fan 25 and the inside air circulation fan 26 is stopped. Thereby, the gas movement between the outside air and the inside air through the ventilation filter 24 is stopped, and the decrease in the carbon dioxide concentration in the housing 10 is stopped. Thereafter, when the carbon dioxide concentration in the housing 10 increases due to the respiration of fruits and vegetables, the above processing is repeated.

  Next, when the carbon dioxide concentration is within a desired range (2 to 5% for bananas) and the oxygen concentration is within the desired range (16 to 19% for bananas), the humidity sensor 14 It is determined whether or not the humidity detected in (1) exceeds the upper limit of the desired range (95% for bananas). As a result, when the humidity exceeds the upper limit value of the desired range, the outside air circulation fan 25 and the inside air circulation fan 26 are operated to supply outside air and inside air to both surfaces of the ventilation filter 24. What is necessary is just to adjust the ventilation volume of the external air circulation fan 25 and the internal air circulation fan 26 based on the humidity detected with the humidity sensor 14. FIG. Specifically, the larger the difference between the humidity detected by the humidity sensor 14 and the upper limit value of the desired range, the higher the air exchange amount of the outside air circulation fan 25 and the inside air circulation fan 26 in order to increase the molecular exchange efficiency in the ventilation filter 24. Should be increased.

Thereby, water vapor | steam moves from the inside air with high humidity to the outside air with low humidity through the ventilation filter 24, and the humidity in the housing | casing 10 falls. At this time, for other gases (O ₂ , CO ₂ ) in which a difference in concentration is generated between the outside air and the inside air, the outside air circulation blower 25 and the inside air circulation blower 26 are operated, so The difference in density becomes smaller.

  When the outside air has a higher humidity than the inside air humidity, even if the outside air circulation blower 25 and the inside air circulation blower 26 are operated, the humidity inside the housing 10 cannot be lowered. A humidity sensor to detect is provided, and the outside air circulation fan 25 and the inside air circulation fan 26 are operated when the outside air is lower in humidity than the inside air humidity in addition to the humidity of the inside air exceeding the upper limit of the desired range. You may do it.

  After the outside air circulation blower 25 and the inside air circulation blower 26 are activated, it is determined whether or not the humidity has reached the lower limit value of the desired range (95% in the case of a banana). As a result, when the humidity reaches the lower limit value of the desired range, the operation of the outside air circulation fan 25 and the inside air circulation fan 26 is stopped. Thereby, the gas movement between the outside air and the inside air through the ventilation filter 24 is stopped, and the decrease in the humidity in the housing 10 is stopped. Thereafter, when the humidity in the housing 10 increases due to the evaporation of moisture from the fruits and vegetables, the above process is repeated.

  Further, during the operation of the outside air circulation blower 25 and the inside air circulation blower 26, the flow rate of the outside air generated by the outside air circulation blower 25 and the flow rate of the inside air generated by the inside air circulation blower 26 are made different so that the gas in the ventilation filter 24 can be changed. Can be promoted. Hereinafter, this point will be described.

  FIG. 2 is a cross-sectional view showing the flow of outside air in the outside air flow path 22 and the flow of inside air in the inside air flow path 23. In the example shown in FIG. 2, in this embodiment, the flow rate Q2 of the internal air flowing through the internal air flow channel 23 is larger than the flow rate Q1 of the external air flowing through the external air flow channel 22, and the internal pressure is higher than the static pressure P1 of the external air flow channel 22. The static pressure P2 of the air flow path 23 is higher. As described above, when the flow rate Q1 of the outside air is different from the flow rate Q2 of the inside air, and the static pressure P1 of the outside air flow path 22 is different from the static pressure P2 of the inside air flow path 23, as shown by the broken line, A vertical flow can be generated on the surface. Thereby, the stay of gas near the surface of the ventilation filter 24 is reduced or eliminated, the molecular exchange efficiency of the ventilation filter 24 can be improved, and gas permeation can be promoted.

According to the present embodiment described above, by using the ventilation filter 24, it is possible to move only gases (O ₂ , CO ₂ , H ₂ O) that have a difference in concentration between the outside air and the inside air. As a result, there is no movement of a gas (for example, N ₂ ) that has no difference in concentration between the outside air and the inside air, so that the inside air that has been temperature adjusted (cooled in this embodiment) is released to the outside more than necessary. This can prevent the thermal load on the container 1.

Further, in the present embodiment, O ₂ sensor 12, CO ₂ sensor 13, by performing the control of the air flow rate of the outside air circulating blower 25 and recirculated air blower 26 based on the sensor signal of the humidity sensor 14, the oxygen concentration in the housing 10 The carbon dioxide concentration and humidity can be adjusted to desired ranges. Thereby, even if the kind of fruit and vegetables accommodated in the housing | casing 10 is changed, the oxygen concentration in a housing | casing 10 and a carbon dioxide concentration and humidity can be hold | maintained in the range suitable for the kind of fruit and vegetables.

  Further, in this embodiment, since the gas moves through the ventilation filter 24 due to the concentration difference between the outside air and the inside air, the casing 10 has a simple configuration in which the flow of the outside air and the inside air is generated by the blowers 25 and 26. The gas concentration inside can be adjusted.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG. Hereinafter, description of the same parts as those in the first embodiment will be omitted, and only different parts will be described.

  FIG. 3 is a conceptual diagram showing the configuration of the container 1 of the second embodiment. As shown in FIG. 3, in the second embodiment, the internal air circulation fan 26 is not provided in the internal air flow path 23, and the internal air flow path switching door 27 is provided at the inlet of the internal air flow path 23. In the example shown in FIG. 3, the flow of the inside air generated by the inside air circulation blower 11 is counterclockwise. For this reason, in the inside air flow path 23 arrange | positioned at the upper part of the housing | casing 10, the right side is an inlet part and the left side is an outlet part.

  The inside air flow path switching door 27 is configured to be rotatable by a motor. When the inside air flow path switching door 27 is in the closed position indicated by a broken line, the flow of the inside air generated by the inside air circulation blower 11 is not introduced into the inside air passage 23. On the other hand, when the inside air flow path switching door 27 is in the open position indicated by the solid line, the flow of the inside air generated by the inside air circulation blower 11 is introduced into the inside air passage 23. Further, by adjusting the opening / closing angle of the inside air flow path switching door 27, the flow rate of the inside air flowing through the inside air flow path 23 can be adjusted. That is, by increasing the open / close angle of the internal air flow path switching door 27, the flow rate of the internal air flowing through the internal air flow path 23 can be increased, and by reducing the open / close angle of the internal air flow path switch door 27, the internal air flow The flow rate of the inside air flowing in the path 23 can be reduced.

The inside air flow path switching door 27 is operated by a control signal output from the control unit 50. That is, in the second embodiment, the control unit 50 performs open / close control of the outside air circulation fan 25 and the inside air flow path switching door 27 based on the sensor signals of the O ₂ sensor 12, the CO ₂ sensor 13, and the humidity sensor 14. It is configured as follows.

  According to the second embodiment described above, by using the flow of the internal air generated by the internal air circulation blower 11, the powered internal air circulation blower 26 can be omitted, and the configuration of the container 1 is simplified. can do.

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to FIGS. In the third embodiment, the configuration of the outside air circulation blower 25 is different from that in the above embodiments. Hereinafter, description of the same parts as those in the above embodiments will be omitted, and only different parts will be described.

  FIG. 4 shows an example of a cross-sectional configuration of the ventilation filter unit 20 of the third embodiment, and corresponds to a modification of the first embodiment in which the inside air circulation blower 26 is provided. In the example shown in FIG. 4, the inside-air circulating blower 26 includes a blower fan 26a, a motor 26b that rotationally drives the blower fan 26a, and a drive gear portion 26c provided on the drive shaft of the motor 26b. The outside air blower 28 includes a blower fan 28a and a driven gear portion 28b. The outside air blower 28 of the third embodiment does not have a motor, and is configured as a blower fan that operates dynamically according to the inside air circulation blower 26.

  Furthermore, a power transmission member 29 for transmitting the rotational driving force of the motor 26b of the inside air circulation blower 26 to the outside air blower 28 is provided. The power transmission member 29 includes a rotating shaft 29a and gear portions 29b and 29c provided at both ends thereof. The rotation shaft 29 a of the power transmission member 29 is provided so as to straddle the outside air passage 22 and the inside air passage 23. The inside air side gear portion 29b provided at the end of the rotating shaft 29a on the inside air flow path 23 side meshes with the drive gear portion 26c of the inside air circulation blower 26, and the outside air provided at the end on the outside air passage 22 side. The side gear portion 29 c meshes with the driven gear portion 28 b of the outside air blower 28.

  With such a configuration, when the inside air circulation blower 26 is activated, the motor 26b of the inside air circulation blower 26 can rotationally drive the blower fan 26a of the inside air circulation blower 26 and simultaneously rotate the outside air blower 28. As a result, an internal air flow is generated in the internal air flow path 23, and an external air flow is generated in the external air flow path 22.

  FIG. 5 shows another example of the cross-sectional configuration of the ventilation filter unit 20 of the third embodiment, and corresponds to a modification of the second embodiment in which the inside air circulation blower 26 is not provided. The example shown in FIG. 5 differs from the example shown in FIG. 4 in the configuration of the power transmission member 29. The power transmission member 29 of FIG. 5 is provided with a fan 29d that rotates in response to the flow of the inside air at the end of the rotating shaft 29a on the inside air flow path 23 side. That is, in the example shown in FIG. 5, the power transmission member 29 rotates using the fluid energy of the inside air flowing through the inside air flow path 23 as a driving force, and the outside air blower 28 is driven to rotate. As a result, an internal air flow is generated in the internal air flow path 23, and an external air flow is generated in the external air flow path 22.

  According to the third embodiment described above, the outside air circulation blower 25 provided with power (motor) can be omitted, and the configuration of the blowing means that generates the flow of outside air can be simplified. In the configuration shown in FIG. 4, the relationship between the devices provided in the outside air passage 22 and the inside air passage 23 may be reversed. That is, an outside air circulation fan 25 having a motor is provided in the outside air flow path 22, an inside air blower without a motor is provided in the inside air flow path 23, and the rotational driving force of the outside air circulation blower 25 is transmitted to the inside air blower via the power transmission member 29. It should be communicated.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described with reference to FIG. Hereinafter, description of the same parts as those in the above embodiments will be omitted, and only different parts will be described.

  FIG. 6 is a conceptual diagram of the container 1 according to the fourth embodiment. As shown in FIG. 6, the container 1 of this embodiment is provided with a capacitor 30 and an evaporator 31 that constitute a refrigeration cycle. The condenser 30 is disposed in the outside air introduction passage 32 through which outside air is introduced, and the evaporator 31 is disposed in the inside air circulation passage 33 through which the inside air passes. The outside air passing through the outside air introduction flow path 32 increases its temperature by exchanging heat with the high-temperature refrigerant in the condenser 30, and the inside air passing through the inside air circulation flow path 33 is heat-exchanged with the low-temperature refrigerant by the evaporator 31 and decreases in temperature.

  In the present embodiment, the outside air introduction flow path 32 is provided at the lower corner of the housing 10. Although not shown, the compressor of the refrigeration cycle and the like are installed in the space below the condenser 30 in the outside air introduction flow path 32. In the example shown in FIG. 6, the capacitor 30 and the evaporator 31 are disposed substantially horizontally in the vicinity of the right side wall of the housing 10, and the evaporator 31 is inclined slightly downward toward the right side wall. The evaporator 31 is located above the capacitor 30.

  In the present embodiment, the outside air circulation blower 25 is configured as a condenser fan that blows outside air to the capacitor 30, and the inside air circulation blower 26 is configured as an evaporator fan that blows inside air to the evaporator 31. The outside air circulation blower 25 is provided on the downstream side of the air flow of the condenser 30, and the outside air sucked by the outside air circulation blower 25 is supplied to the condenser 30. The inside air circulation blower 26 is provided on the upstream side of the air flow of the evaporator 31, and the inside air pushed out from the inside air circulation blower 26 is supplied to the evaporator 31. In addition, the container 1 of this embodiment is comprised as a freezing container. For this reason, the inside air always passes through the evaporator 31 and is cooled.

  A partition wall 34 is provided inside the housing 10 so as to partition the inside of the box where the inside air circulates and the outside of the box where the outside air is introduced. The ventilation filter 24 of the present embodiment is provided on the partition wall 34. The ventilation filter 24 is provided on the downstream side of the air flow from the condenser 30 in the outside air introduction passage 32 and on the downstream side of the air flow from the evaporator 31 in the inside air circulation passage 33. The outside air heated by the capacitor 30 flows downstream of the condenser 30 in the outside air introduction flow path 32. When the outside air heated by the condenser 30 and the low-temperature inside air cooled by the evaporator 31 are brought into contact with each other through the ventilation filter 24, heat loss increases, and the cooling efficiency of the container 1 decreases. Become. For this reason, in the present embodiment, a bypass flow path 35 is provided in order to bypass the capacitor 30 and take outside air into the outside air flow path 22.

  In FIG. 6, the outside air flow path 22 and the bypass flow path 35 are indicated by broken lines. The bypass flow path 35 is provided on the downstream side of the air flow of the condenser 30 in the outside air introduction flow path 32 and is shifted from the outside air circulation fan 25 in the direction perpendicular to the paper surface. Since the outside air introduced from the bypass flow path 35 reaches the ventilation filter 24 without passing through the condenser 30, it is not affected by the heat of the condenser 30. The bypass flow path 35 of the present embodiment is formed perpendicular to the ventilation filter 24. For this reason, the outside air introduced into the bypass passage 35 bends at a right angle and then flows through the outside air passage 22.

  The inside air passage 23 is provided with inside air passage switching doors 27a and 27b for communicating or blocking the inside air passage 23 and the inside air circulation passage 33. A first inside air flow path switching door 27a is provided on the upstream side of the inside air flow path 23, and a second inside air flow path switching door 27b is provided on the downstream side of the air flow. As in the second embodiment, the inside air flow path switching doors 27a and 27b are configured to be rotatable by a motor. The inside air flow path switching doors 27a and 27b are controlled to be opened and closed by a control unit 50 (not shown in FIG. 6) based on sensor signals from the sensors 12 to 14.

  In the example shown in FIG. 6, the flow direction of the outside air in the outside air flow path 22 is a direction from bottom to top, and the flow direction of the inside air in the inside air flow path 23 is a direction from top to bottom. That is, in the present embodiment, the flow is a counter flow in which the flow directions of the inside air and the outside air are opposite via the ventilation filter 24. When comparing this counter flow with a cross flow in which the flow directions of the inside air and the outside air are orthogonal, and a parallel flow in which the flow directions of the inside air and the outside air are parallel, the molecular exchange efficiency of the ventilation filter 24 is highest in the counter flow, The order is cross flow and parallel flow. For this reason, molecular exchange can be effectively performed by the ventilation filter 24 by making the flow of the inside and outside air through the ventilation filter 24 counter flow. The heat exchange efficiency of the inside and outside air through the ventilation filter 24 is also highest in the counter flow, followed by the cross flow and the parallel flow, and the counter flow has the largest heat loss. For this reason, the balance between the molecular exchange efficiency and the heat loss by the ventilation filter 24 may be achieved, and the flow of the inside and outside air through the ventilation filter 24 may be a cross flow.

  According to the fourth embodiment described above, the condenser fan is used as the outside air circulation and the evaporator fan is used as the inside air circulation blower 26, so that the outside air and the inside air are supplied to the ventilation filter 24 using the existing device. be able to. Thereby, the structure of the container 1 can be simplified compared with the case where the exclusive external air circulation fan 25 and the inside air circulation fan 26 are provided.

  Further, by providing a bypass flow path 35 for taking outside air into the outside air flow path 22, the influence of the heat of the capacitor 30 on the ventilation filter 24 provided on the downstream side of the air flow of the capacitor 30 in the outside air introduction flow path 32. The outside air can be supplied without receiving. As a result, the temperature difference between the outside air in the outside air flow path 22 and the inside air in the inside air flow path 23 can be reduced to reduce heat loss, and the system efficiency is reduced due to the contact between the inside and outside air via the ventilation filter 24. Can be suppressed.

[Fifth Embodiment]
Next, a fifth embodiment of the present invention will be described with reference to FIG. In the fifth embodiment, the position of the ventilation filter 24 is different from that in the fourth embodiment. Hereinafter, description of the same parts as those in the above embodiments will be omitted, and only different parts will be described.

  FIG. 7 is a conceptual diagram of the container 1 according to the fifth embodiment. Also in this embodiment, the ventilation filter 24 is provided in the partition wall 34 that partitions the outside air introduction channel 32 and the inside air circulation channel 33. In this embodiment, the ventilation filter 24 is provided on the upstream side of the air flow from the condenser 30 in the outside air introduction flow path 32 and on the downstream side of the air flow from the evaporator 31 in the inside air circulation flow path 33. In the vicinity of the outside air side of the ventilation filter 24, an outside air channel forming member 36 for forming the outside air channel 22 is provided. Since the outside air introduced into the outside air introduction flow path 32 flows around the outside air flow path forming member 36 and flows into the outside air flow path 22, the outside air introduced into the outside air introduction flow path 32 directly blows to the ventilation filter 24. There is nothing.

  The outside air flow path forming member 36 is formed from the condenser 30 in the outside air introduction flow path 32 to the downstream side of the air flow. For this reason, the outside air that has passed through the outside air flow path 22 can flow downstream of the condenser 30 in the outside air introduction flow path 32 without passing through the condenser 30.

  Also according to the fifth embodiment described above, by using a condenser fan as the outside air circulation blower 25 and an evaporator fan as the inside air circulation blower 26, the outside air and the inside air are supplied to the ventilation filter 24 using an existing device. The configuration of the container 1 can be simplified. In the fifth embodiment, since the ventilation filter 24 is disposed on the upstream side of the condenser 30 in the outside air introduction flow path 32, it is necessary to provide the bypass flow path 35 as in the fourth embodiment. Absent.

[Sixth Embodiment]
Next, a sixth embodiment of the present invention will be described with reference to FIG. In the sixth embodiment, the position of the ventilation filter 24 is different from that in the fourth and fifth embodiments. Hereinafter, description of the same parts as those in the above embodiments will be omitted, and only different parts will be described.

  FIG. 8 is a conceptual diagram of the container 1 according to the sixth embodiment. Also in this embodiment, the ventilation filter 24 is provided in the partition wall 34 that partitions the outside air introduction channel 32 and the inside air circulation channel 33. In the present embodiment, the ventilation filter 24 is provided on the downstream side of the air flow from the condenser 30 in the outside air introduction flow path 32 and on the downstream side of the air flow from the evaporator 31 in the internal air circulation flow path 33.

  In the present embodiment, the ventilation filter 24 is disposed on the surface of the partition wall 34 that faces the evaporator 31, and the ventilation filter 24 is located immediately below the evaporator 31. For this reason, when the water drop which fell from the evaporator 31 at the time of a defrost operation flows into the filter 24 for ventilation, there exists a possibility of causing the fall of the permeation | transmission performance of the filter 24 for ventilation. Therefore, in the present embodiment, a rib 37 is provided in the vicinity of the ventilation filter 24 in the partition wall 34 in order to prevent water droplets from flowing into the ventilation filter 24. In the example shown in FIG. 8, the surface of the partition wall 34 facing the evaporator 31 is slightly lowered to the left, so that water droplets flow in the left direction. Therefore, the rib 37 is provided on the right side of the ventilation filter 24 in the partition wall 34.

  The outside air heated by the capacitor 30 flows downstream of the condenser 30 in the outside air introduction flow path 32. When the outside air heated by the condenser 30 and the low-temperature inside air cooled by the evaporator 31 are brought into contact with each other through the ventilation filter 24, heat loss increases, and the cooling efficiency of the container 1 decreases. Become. For this reason, in this embodiment, the bypass flow path 35 is provided in order to take in external air to the external air flow path 22 of the ventilation filter 24 similarly to the said 4th Embodiment. Thereby, outside air can be supplied to the ventilation filter 24 provided on the downstream side of the air flow of the condenser 30 in the outside air introduction flow path 32 without being affected by the heat of the condenser 30. As a result, the temperature difference between the outside air in the outside air passage 22 and the inside air in the inside air passage 23 can be reduced to reduce heat loss, and a reduction in system efficiency can be suppressed.

  In the example shown in FIG. 8, the flow direction of the outside air in the outside air flow path 22 is a direction from right to left, and the flow direction of the inside air in the inside air flow path 23 is a direction from right to left. That is, in this embodiment, the flow direction of the inside air and the outside air is the parallel flow through the ventilation filter 24.

  Also according to the sixth embodiment described above, by using a condenser fan as the outside air circulation blower 25 and an evaporator fan as the inside air circulation blower 26, the outside air and the inside air are supplied to the ventilation filter 24 using an existing device. The configuration of the container 1 can be simplified. In the sixth embodiment, the ventilation filter 24 is provided at a position facing the evaporator 31. Therefore, the ventilation filter 24 is close to the inside air circulation blower 26, and the inside air sent from the inside air circulation blower 26 can be easily supplied to the ventilation filter 24, and the power of the inside air circulation blower 26 can be effectively used. .

[Other Embodiments]
As mentioned above, although embodiment of this invention was described, this invention is not limited to this, Unless it deviates from the range described in each claim, it is not limited to the wording of each claim, and those skilled in the art Improvements based on the knowledge that a person skilled in the art normally has can be added as appropriate to the extent that they can be easily replaced.

  For example, in each of the above-described embodiments, the example in which the inside of the housing 10 is frozen or refrigerated as the container 1 has been described. However, the present invention is not limited to this, and it is only necessary to adjust the temperature in the housing 10. It is good also as a structure which adjusts the inside temperature to normal temperature or high temperature from normal temperature.

Further, in each of the above embodiments, the O ₂ sensor 12, the CO ₂ sensor 13, and the humidity sensor 14 are used to perform the air volume control of the blowers 25 and 26 and the open / close control of the internal air flow path switching door 27. One or two of the sensors 12, 13, and 14 may be used to perform air volume control of the fans 25 and 26 and open / close control of the inside air flow path switching door 27.

  Moreover, in each said embodiment, although it comprised so that a ventilation means may be provided in each of the external air flow path 22 and the internal air flow path 23, it is not restricted to this, A ventilation means is provided in at least one of the external air flow path 22 and the internal air flow path 23. Should just be provided.

  Moreover, in each said embodiment, although the example which accommodates fruits and vegetables in the housing | casing 10 was demonstrated, not only this but the object accommodated in the housing | casing 10 requires temperature adjustment, and it is inside air during accommodation. What is necessary is just to change the concentration of a specific kind of gas. For example, it may be a fresh food of a different type or a fresh flower.

(Asymmetric membrane)
FIG. 9 is a cross-sectional view showing one embodiment of the asymmetric membrane. An asymmetric membrane 100 shown in FIG. 9 includes a porous layer 3 and a dense layer 5 adjacent to the porous layer 3. The dense layer 5 is a layer generally sometimes referred to as a “skin layer” in the technical field. The porous layer 3 and the dense layer 5 are integrally formed of the same polymer material. The dense layer 5 has pores of nanometer size or micrometer size. (For example, 20 to 80 nanometers).

In addition, a filler can be dispersed in the asymmetric membrane 100. The asymmetric membrane 100 can include only a polymer material forming an asymmetric structure having the porous layer 3 and the dense layer 5 or a polymer material and a filler as main components, but further includes other components. You may go out.
The thickness of the asymmetric membrane 100 is preferably 0.1 to 10 μm.

  The dense layer 5 has a function of selectively allowing gas to pass while preventing permeation of fine particles. Therefore, the dense layer 5 only needs to have a dense property that can sufficiently prevent the permeation of fine particles. Specifically, nanometer-size or micrometer-size holes are formed on the surface of the dense layer 5. However, in the dense layer 5, pores having a pore volume smaller than that of the porous layer 3 may be formed in an open or semi-open bubble state.

  In order to ensure sufficient gas permeability, the dense layer 5 preferably has a thickness of 1 μm or less. The film thickness of the dense layer 5 is preferably 0.005 μm or more, more preferably 0.01 μm or more.

  The porous layer 3 functions as a support for the dense layer 5 while maintaining gas permeability at a high level. If the thickness of the dense layer 5 is reduced in order to ensure sufficient gas permeability, the dense layer 5 alone may lack the strength of the entire film, but the porous layer 3 supports the dense layer 5. By functioning as a support, sufficient mechanical strength and handleability are maintained for the asymmetric membrane 100 as a whole. From such points, the film thickness of the porous layer 3 is preferably 1 to 500 μm.

  In order to achieve the object of the present invention at a particularly high level, the asymmetric membrane 100 is preferably a membrane whose gas permeation rate depends on the molecular weight of the gas. In other words, it is preferable that the Knudsen flow is dominant in the gas flow in the asymmetric membrane 100. The “Knusen flow” refers to a flow of gas that is so thin that the movement of molecules becomes a problem (see Chemical Dictionary 3, Chemistry Dictionary Editorial Committee, page 44). Knudsen flow is dominant. The gas permeation rate depends on the reciprocal of the square root of its molecular weight.

In a membrane in which gas is permeable by an ideal Knudsen flow, the gas permeability coefficient P is inversely proportional to the square root of its molecular weight. For example, when the gas components to be permeated are oxygen and carbon dioxide, their separation ratio α is 1.17 as shown in the following formula (4). In the formula (4), P (O ₂ ) and P (CO ₂ ) indicate oxygen and carbon dioxide permeability coefficients, respectively, and M (O ₂ ) and M (CO ₂ ) indicate molecular weights of oxygen and carbon dioxide, respectively. .

  On the other hand, there is a gas flow called “dissolved diffusion flow”. The dissolved diffusion flow refers to a flow that depends on the product of the solubility of the gas in the membrane and the diffusion coefficient of the gas in the membrane, and the permeation rate of the gas in the membrane by the dissolved diffusion flow is generally slower than that of the Knudsen flow. In conventional polymer membranes, the dissolved diffusion flow is often dominant in the gas flow that permeates the membrane. In a membrane where the dissolved diffusion flow is dominant, since the carbon dioxide permeation rate is generally larger than the oxygen permeation rate, the separation ratio α of oxygen and carbon dioxide is less than 1.0 (depending on the polymer). It is known that the difference is about 0.3 to 0.7.

As described above, it is possible to evaluate the state of the gas flow that permeates the membrane using the value of the separation ratio α as an index. In an actual membrane, although each type of flow is considered to be generated in combination, the separation ratio α (= P (O ₂ ) / P (CO ₂ )) satisfies the following formula (3). If it is within the range, the Knudsen flow can be regarded as dominant. The oxygen permeability coefficient P (O ₂ ) and the carbon dioxide permeability coefficient P (CO ₂ ) are measured under conditions of 23 ± 2 ° C. and substantially no pressure (total pressure) difference between the membranes.
1.0 <P (O ₂ ) / P (CO ₂ ) <1.70 (3)

  The reason why the Knudsen flow is dominant in the asymmetric membrane 100 is not necessarily clear, but the present inventors consider as follows.

  First, it is considered that the gas permeability coefficient of the asymmetric membrane 100 depends on the permeability of the dense layer 5 and the influence of the porous layer 3 is small. Here, it is considered that a Knudsen flow is generated in the holes formed in the surface of the dense layer 5 and / or a space inside the dense layer 5, and a dissolved diffusion flow is generated in the other dense layers 5. At this time, since there are more channels through which the gas permeates by the Knudsen flow than channels through which the dissolved diffusion flow permeates, the Knudsen flow becomes dominant, and it is assumed that the gas permeability is dramatically improved. Further, it is considered that suspended substances in the atmosphere such as dust and dust can be removed in the portion where the gas permeates through the dissolved diffusion flow.

  In addition, when the filler is dispersed in the asymmetric membrane 100 as described above, in addition to the pores formed on the surface of the dense layer 5 and / or the space inside the dense layer 5, the interface between the filler and the polymer Since a Knudsen flow is generated even in the gap, the gas permeability of the asymmetric membrane 100 is further improved.

(Polymer material)
(I) Monomer composition The polymer material can be obtained by polymerizing a monomer composition containing a monomer represented by the following formula (1).

In the formula (1), R ¹ is an alkyl group having 1 to 12 carbon atoms and / or an aryl group having 6 to 10 carbon atoms. Examples of the alkyl group having 1 to 12 carbon atoms include a methyl group, an ethyl group, an n-propyl group, a butyl group, and a pentyl group, and a methyl group is preferable. Examples of the aryl group having 6 to 10 carbon atoms include a phenyl group and a naphthyl group, and a phenyl group is preferable.

  a is an integer of 1 to 3, and is preferably 3. b is an integer of 0 to 2, preferably 0 or 1, and most preferably 0.

X is a chain polysiloxane residue represented by the following formula (i) or a cyclic polysiloxane residue represented by the following formula (ii).

In the formula, R ² independently of each other is an alkyl group having 1 to 12 carbon atoms, and more specifically includes the groups described above for R ¹ , and is preferably a methyl group. d is an integer of 1 to 5, and c is an integer of 3 to 5.

  The following are illustrated as a monomer shown by Formula (1). In the formula, Me represents a methyl group.

The monomer represented by the formula (1) can be prepared by a Diels-Alder reaction between a vinyl group-containing compound represented by the following formula (5) or (6) and cyclopentadiene.

(Here, R ¹ , X, and a are as described above.)

(Here, R ¹ , R ² and c are as described above.)

  As an example of a vinyl group-containing compound for preparing a monomer represented by the formula (1), wherein X is a group represented by the above formula (i), tristrimethylsiloxyvinylsilane is used, As an example of the vinyl group-containing compound for preparing the group represented by the formula, a vinyl group-containing compound represented by the above formula (6) can be exemplified.

  The monomer composition may contain a cyclic olefin represented by the following formula (4).

In the formula (4), R ^{3 to} R ⁶ are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group, a cycloalkyl group, an aryl group, an alkoxy group, an aryloxy group, and a halogenated group. It is a group selected from a hydrocarbon group, a polar group selected from an oxetanyl group and an alkoxycarbonyl group, a polyoxyalkylene group, or a group selected from an alkoxysilyl group. R ³ and R ⁴ or R ³ and R ⁶ may form an alicyclic structure, an aromatic ring structure, a carboimide group, or an acid anhydride group together with the carbon atoms to which they are bonded. b is an integer of 0-2. Preferably, R ³ is a hydrogen atom.

  Examples of the alicyclic structure include those having 4 to 10 carbon atoms. Examples of these structures are as follows. In the following examples, Me represents a methyl group and Ph represents a phenyl group.

(II) Addition polymer The addition polymer contains a repeating unit represented by the following formula (7) derived from the monomer represented by the above formula (1). When controlling the size of the micropores of the asymmetric membrane, it is preferable to use an addition polymer rather than the ring-opening polymer described later, because an asymmetric membrane having finer pores can be obtained.

(Here, R ¹ , X, a, and b are as described above. In addition, for the repeating unit (7) in the addition polymer, R ¹ , X, a, and b may be the same, May be different.)

  The addition polymer is a copolymer containing a repeating unit represented by the following formula (8) derived from the monomer represented by the formula (4) in addition to the repeating unit represented by the above (7). Also good. The bond between the repeating units (7) and (8) is random.

(Here, R ^{3 to} R ⁶ and b are as described above. In addition, for the repeating unit (8) in the addition polymer, R ^{3 to} R ⁶ and b may be the same or different. May be.)

  The ratio of the repeating unit of formula (8) is preferably in the range of 0 to 60% of the total number of repeating units, more preferably 0 to 40%. When the upper limit value of the ratio is exceeded, the effect of X in formula (1) tends to decrease.

  The polymer preferably has a polystyrene-equivalent number average weight molecular weight determined by GPC of 10,000 to 2,000,000, more preferably 300,000 to 1,000,000. When the molecular weight exceeds the upper limit, it is practically difficult to synthesize. On the other hand, when the molecular weight is lower than the lower limit, the strength of the film tends to decrease.

  In addition polymerization, the above-mentioned monomer composition is dissolved in an aromatic hydrocarbon solvent such as toluene or xylene according to a conventional method, and in the presence of a polymerization catalyst and a promoter, at a temperature of 20 to 40 ° C. under normal pressure. Then, polymerization is carried out by stirring in an inert gas atmosphere. The polymerization catalyst is selected from Group 8 element, Group 9 element, and Group 10 element of the periodic table, for example, iron (Fe), cobalt (Co), nickel (Ni), ruthenium (Ru), rhodium (Rh). ), Palladium (Pb), and metallocene complexes with central metals such as platinum (Pt), preferably nickel (Ni) or palladium (Pd) metallocene catalysts. As the promoter, an organoaluminum compound can be used, and methylaluminoxane is preferable.

The above catalyst and cocatalyst are used in the following amounts.
The catalyst is preferably 0.01 to 100 mmol atoms with respect to 1 mol in total of the monomers represented by the formulas (1) and (2). The cocatalyst is preferably 0.5 to 10,000 moles per mole of catalyst.

  Moreover, you may add a molecular weight modifier in a polymerization system as needed. Molecular weight regulators include hydrogen, α-olefins such as ethylene, butene and hexene, aromatic vinyl compounds such as styrene, 3-methylstyrene and divinylbenzene, unsaturated ethers such as ethyl vinyl ether, tris (trimethylmethoxy) vinylsilane, divinyl Examples thereof include vinyl silicon compounds such as dihydrosilane and vinylcyclotetrasiloxane.

In addition, since the ratio of the solvent and the monomer, the polymerization temperature, the polymerization time, and the amount of the molecular weight modifier described above are significantly affected by the catalyst used, the monomer structure, and the like, it is difficult to generally limit them. In order to obtain the polymer having the above specific structure, it is necessary to use properly depending on the purpose.
The molecular weight of the polymer is controlled by the amount of the polymerization catalyst and the addition amount of the molecular weight modifier, the conversion rate from the monomer to the polymer, or the polymerization temperature.

  The polymerization is stopped by a compound selected from water, alcohol, ketone, organic acid and the like. The catalyst residue can be separated and removed from the polymer solution by adding a mixture of an acid water such as lactic acid, malic acid, and oxalic acid to the polymer solution. For removal of the catalyst residue, adsorption removal using activated carbon, diatomaceous earth, alumina, silica or the like, filtration separation removal using a filter or the like can be applied.

  The polymer can be obtained by putting the polymerization solution in alcohols such as methanol and ethanol, and ketones such as acetone and methyl ethyl ketone, solidifying, and drying under reduced pressure usually at 60 ° C. to 150 ° C. for 6 to 48 hours. . In this step, catalyst residues and unreacted monomers remaining in the polymer solution are also removed. Moreover, the unreacted monomer containing siloxane can be easily removed by using a solvent in which cyclic alcohols such as octamethylcyclotetrasiloxane and decamethylcyclopentasiloxane are mixed with the alcohols and ketones.

(III) Ring-opening polymer The ring-opening polymer contains a repeating unit represented by the following formula (9) derived from the monomer represented by the above formula (1).

(Here, R ¹ , X, a, and b are as described above. Note that R ¹ , X, a, and b may be the same for the repeating unit (9) in the ring-opening polymer). , May be different.)

  The ring-opening polymer may be a copolymer containing a repeating unit of the following formula (10) derived from the monomer represented by the formula (4) in addition to the repeating unit (9). The combination of units (9) and (10) is random.

(Here, R ^{3 to} R ⁶ and b are as described above. In addition, for the repeating unit (10) in the ring-opening polymer, R ^{3 to} R ⁶ and b may be the same or different. May be.)

  The ratio of the repeating unit of formula (10) is preferably in the range of 5% to 50%, more preferably 10 to 30% of the total number of repeating units. If the ratio is less than the lower limit, only a polymer having a low molecular weight can be obtained, and the coating property tends to decrease. If the ratio exceeds the upper limit, the effect of X in the formula (1) decreases. Tend to.

The polymer or copolymer (hereinafter abbreviated as “polymer”) may be one in which at least a part of the carbon-carbon double bond of the main chain is hydrogenated. Hydrogenation improves the thermal stability of the polymer. The hydrogenation rate can be obtained, for example, by comparing the peak intensity after hydrogenation with the peak intensity derived from the main chain carbon-carbon double bond in the ¹ H-NMR spectrum of the polycycloolefin before hydrogenation. it can. Preferably, 50 to 100%, more preferably 80% or more, and most preferably 90% or more of the carbon-carbon double bonds of the main chain are hydrogenated.

  The polymer preferably has a polystyrene-equivalent number average weight molecular weight determined by GPC of 10,000 to 2,000,000, more preferably 300,000 to 1,000,000. When the molecular weight exceeds the upper limit, it is practically difficult to synthesize. On the other hand, when the molecular weight is lower than the lower limit, the strength of the film tends to decrease.

  In the ring-opening metathesis polymerization, according to a conventional method, the above monomer composition is dissolved in an aromatic hydrocarbon solvent such as toluene or xylene, and in the presence of a polymerization catalyst, at a temperature of 40 to 60 ° C. under normal pressure, The polymerization is carried out under stirring in a nitrogen atmosphere. As the polymerization catalyst, tungsten, molybdenum or ruthenium complex called carbene complex can be used, preferably Grubbs first generation catalyst, Grubbs second generation catalyst or Hoveyda-Grubbs catalyst. The amount of the catalyst used can be polymerized at a concentration of 1 to 1000 ppm, preferably 5 to 500 ppm, relative to the raw material monomer. If it is less than 5 ppm, the polymerization rate is slow and the practicality is poor, and if it exceeds 500 ppm, it may be economically undesirable.

  The hydrogenation reaction of the obtained polymer is performed, for example, by converting the main chain carbon-carbon double bond of the silicone-modified polycycloolefin into a saturated single bond using hydrogen gas in the presence of a hydrogenation catalyst. be able to.

  The hydrogenation catalyst to be used is not particularly limited, such as a homogeneous catalyst and a heterogeneous catalyst, and those generally used for hydrogenation of olefin compounds can be appropriately used.

  Examples of the homogeneous catalyst include, for example, dichlorotris (triphenylphosphine) rhodium known as a Wilkinson complex, a ruthenium carbene complex catalyst described in the above metasis polymerization catalyst, JP-A-7-2929, JP-A-11-109460, JP-A-11-158256. And transition metal complex catalysts composed of ruthenium compounds described in JP-A-11-193323 and the like.

  Examples of the heterogeneous catalyst include a hydrogenation catalyst in which a metal such as nickel, palladium, platinum, rhodium, or ruthenium is supported on a carrier such as carbon, silica, celite, alumina, or titanium oxide. More specifically, for example, nickel-alumina, palladium-carbon and the like can be used. These hydrogenation catalysts can be used alone or in combination of two or more.

  Among these, noble metal complex catalysts such as rhodium and ruthenium, palladium-carbon, etc. from the point that the main chain carbon-carbon double bond of the polymer can be selectively hydrogenated without causing side reactions such as functional groups. It is preferable to use a palladium-supported catalyst, particularly a ruthenium carbene complex catalyst.

  The ruthenium carbene complex catalyst can be used as both a ring-opening metathesis reaction catalyst and a hydrogenation catalyst. In this case, the ring-opening metathesis reaction and the hydrogenation reaction can be performed continuously. When the ring-opening metathesis reaction and the hydrogenation reaction are continuously carried out using the ruthenium carbene complex catalyst, a vinyl compound such as ethyl vinyl ether or a catalyst modifier such as α-olefin is added to activate the catalyst. Thereafter, a method of starting the hydrogenation reaction is also preferably employed.

  The hydrogenation reaction is preferably performed in an organic solvent. As an organic solvent, it can select conveniently by the solubility of the hydride to produce | generate, The organic solvent similar to the above-mentioned polymerization solvent can be used. Therefore, the reaction can be carried out without changing the solvent after the polymerization reaction, either directly from the reaction solution or from the reaction solution or by adding a hydrogenation catalyst.

  The conditions for the hydrogenation reaction may be appropriately selected according to the type of hydrogenation catalyst used. The usage-amount of a hydrogenation catalyst is 0.01-50 weight part normally with respect to 100 weight part of ring-opening polymers, Preferably it is 0.05-10 weight part. When the reaction temperature is 100 ° C. to 200 ° C. or higher, side reactions tend to occur. The reaction pressure of hydrogen is usually 0.01 to 10.0 MPa, preferably 0.1 to 5.0 MPa. When the hydrogen pressure is 0.01 MPa or less, the hydrogenation reaction rate decreases. If it is 5.0 MPa or more, a high voltage device is required.

  By the hydrogenation reaction performed as described above, 50% or more, preferably 80% or more, and most preferably 90% or more of the main chain carbon-carbon double bonds can be hydrogenated.

(IV) Filler It is preferable to disperse the filler in the polymer material from the viewpoint of improving gas permeability.

  As the filler, an organic filler or an inorganic filler can be used. The surface of the filler may be hydrophilic or hydrophobic, but an inorganic filler having a hydrophilic surface is particularly preferable. Examples of such inorganic fillers include oxide fillers made of oxides such as silica, zeolite, alumina, titanium oxide, magnesium oxide, and zinc oxide. Of these, silica fillers are preferred. Examples of the silica filler include spherical silica, porous silica particles, quartz powder, glass powder, glass beads, talc, and silica nanotubes.

  In order to particularly enhance gas permeability, the filler is preferably a porous filler. As the porous filler, mesoporous silica particles, nanoporous silica particles and zeolite particles are preferable. The mesoporous silica particles are porous silica particles having a particle diameter of 500 to 1000 nm in which pores are formed, and the nanoporous silica particles are porous silica particles having a particle diameter of 30 to 100 nm in which pores are formed. In general, mesoporous silica particles have a pore diameter of 3 to 7 nm, and nanoporous silica particles have a pore diameter of 2 to 5 nm. It is considered that the performance of the asymmetric membrane is greatly improved by using a filler having a low apparent density such as a porous filler.

  As needed, you may use the filler which performed the surface treatment using a coupling agent etc., or the hydrophilization by the hydration process.

  The filler content is typically 5 to 500 parts by mass with respect to 100 parts by mass of the polymer material. The content of the filler is more preferably 11 parts by mass or more, further preferably 30 parts by mass or more, and particularly preferably 70 to 400 parts by mass. If the filler content is less than 5 parts by mass, the effect of improving the gas permeability tends to be small, and if it exceeds 500 parts by mass, the mechanical strength of the asymmetric membrane is lowered and it is difficult to make it thin. There is a tendency.

(V) Method for producing asymmetric membrane For example, the asymmetric membrane may be formed by applying the above-described polymer material onto a substrate to form a solution layer, and by partially removing the solvent from the solution layer. Forming a dense layer containing a solution layer on the surface layer opposite to the substrate of the solution layer, and immersing the solution layer on which the dense layer is formed in a poor solvent (coagulation solvent) of the polymer material Forming a porous layer containing the material.

  As the solvent for dissolving the polymer material, aromatic hydrocarbons, aliphatic hydrocarbons, halogenated hydrocarbons, ethers, or ketones are preferably used. Aromatic hydrocarbons include benzene, toluene and xylene. Aliphatic hydrocarbons include hexane, heptane, octane, decane and cyclohexane. Halogenated hydrocarbons include chloroform, methylene chloride and carbon tetrachloride. Ethers include tetrahydrofuran and dioxane. Examples of ketones include ethyl methyl ketone.

  In preparing a polymer solution, a film is often formed by promoting phase separation or adding another substance to adjust the solubility of the polymer and the viscosity of the polymer solution. As such a film-forming preparation agent, a compound having a compatibility of 0.1% or more with respect to the polymer solution can be used. As the regulator, a salt soluble in the polymer solution, water, lower alcohol (methanol, ethanol), amide polar solvent (dimethylformamide, dimethylacetamide) or the like can be used.

  When forming the dense layer, the conditions for removing the solvent (drying method, temperature, time, etc.) are appropriately adjusted so that a dense layer having a desired thickness is formed.

  As the poor solvent (coagulation solvent) used for forming the porous layer, alcohols such as methanol, ethanol and propanol, acetone, or water is preferably used.

  The asymmetric membrane is not limited to the embodiment described above, and can be appropriately modified without departing from the gist of the present invention. For example, the asymmetric membrane may further have a mesh body. In this case, at least one of the porous layer and the dense layer may be impregnated in the mesh body. Alternatively, the mesh body may be laminated on the porous layer or the dense layer. The asymmetric membrane having a mesh body can be produced, for example, by impregnating the above-mentioned mixed solution into the mesh body or applying the mixture on the mesh body.

  The mesh body can improve gas permeability, improve the mechanical strength of the film, and prevent the film from being damaged by external stress. The mesh body may be made of metal or resin, but is preferably made of resin. Examples of the resin forming the mesh body include polyester terephthalate (PET) and polypropylene (PP). Examples of the weaving method of the mesh body include plain weave, twill, plain tatami and twill.

  The surface of the mesh body is preferably treated with an adhesion improver (primer) in order to improve the strength of the asymmetric membrane. As the adhesion improver, a commercially available product can be used.

  Further, the asymmetric membrane may be formed on the support, or the asymmetric membrane may be a hollow fiber membrane.

(Asymmetric membrane structure)
In the container 1, the asymmetric membrane structure 150a shown in FIG. 10 or the asymmetric membrane structure 150b shown in FIG. 11 may be used as a ventilation filter.

  The asymmetric membrane structure 150a in FIG. 10 includes an asymmetric membrane 100a and a support 110a. The asymmetric membrane 100a is planar, and is supported by a planar support 110a that is in close contact with one surface thereof. The support 110a may be in close contact with only a part of the asymmetric membrane 100a, such as the outer peripheral portion of the asymmetric membrane 100a, or may be in complete contact with the asymmetric membrane 100a.

  An asymmetric membrane structure 150b in FIG. 11 includes an asymmetric membrane 100b and a support 110b. The asymmetric membrane 100b has a bowl shape and is supported by a bowl-like support 110b that is in close contact with one surface thereof. The support 110b may be in close contact with only a part of the asymmetric membrane 100b or may be in complete contact with the asymmetric membrane 100b.

  The asymmetric membranes 100a and 100b are composed of a membrane formed of the above-described polymer material, and the thickness is preferably 0.1 to 10 μm. The supports 110a and 110b only need to be gas permeable, and examples thereof include a paper-like fiber member, a porous body having a pore diameter of 0.1 to 500 μm, and a mesh. The thickness of the support is preferably 50 to 500 μm. Moreover, it is preferable that the support bodies 110a and 110b are heat insulating materials. Thereby, it becomes possible to further reduce the thermal load when adjusting the gas concentration in the container 1.

  According to these asymmetric membrane structures 150a and 150b, since the asymmetric membranes 100a and 100b are supported by the support, the asymmetric membranes 100a and 100b are thinned to increase the amount of gas to be transmitted and the asymmetric membrane structure. The strength of the can be ensured. Furthermore, according to the asymmetric membrane structure 150b, since the surface areas of the asymmetric membranes 100a and 100b are increased, the amount of gas permeation can be further increased.

  The above-mentioned asymmetric membrane structure is formed, for example, by forming an asymmetric membrane on a film that can be removed in a later step by the above-described film forming method and transferring the support onto the formed asymmetric membrane. It can manufacture by removing. Examples of the film that can be removed in a subsequent process include a film that is removed by washing with water, a solvent, chemicals, and the like, and a film that is removed after being modified by irradiation with UV, EB, or the like. In addition, as a method for transferring the support onto the asymmetric membrane, a method in which an adhesive or a pressure-sensitive adhesive is interposed between the asymmetric membrane and the support, a method of bonding the asymmetric membrane and the support by heating or dissolution with a solvent, etc. The method of adhering is mentioned.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples.

(Polymer production)
Polymer Production Example 1: Synthesis of Tris (trimethylsiloxy) silylnorbornene ring-opening polymer (Polymer A) Monomer A 20 g (0.51 mmol) represented by the following formula (12) and toluene in a nitrogen-substituted glass container 180 g was mixed and heated to 40 ° C. A solution prepared by dissolving 12 mg (0.015 mmol) of bis (tricyclohexylphosphine) benzylideneruthenium (IV) dichloride in 4 g of toluene was added thereto, and a polymerization reaction was performed at 40 ° C. After the polymerization reaction started, the viscosity of the solution gradually increased, and after 20 minutes, 1 g of ethyl vinyl ether was added to terminate the polymerization. The polymerization solution was poured into a large amount of methanol to aggregate the precipitate, pulverized and washed, filtered, and dried under reduced pressure at 70 ° C. for 5 hours to obtain 19.0 g of Polymer A. The molecular weight was Mn = 550,000 as a polystyrene conversion value by gel permeation chromatography using toluene as a solvent.

Polymer Production Example 2: Synthesis of Tris (trimethylsiloxy) silylnorbornene- b-norbornene addition copolymer (Polymer B) 34.7 g (0.089 mol) of monomer A and monomer B in a nitrogen-substituted glass container 8.3 g (0.089 mol) of (norbornene) and 37 mg (40 μmol) of trityltetra (pentafluorophenyl) borate {[Ph ₃ C] [B (C ₆ F ₅ ) ₄ ]} were dissolved in 140 ml of toluene. Separately prepared catalyst solution (cyclopentadienyl (allyl) palladium [C ₅ H ₅ PdC ₃ H ₅ ] 9 mg (40 μmol), tricyclohexylphosphine [PCy ₃ ] 12 mg (40 μmol) dissolved in toluene 15 ml ) And a polymerization reaction was carried out at room temperature (25 ° C.) for 5 hours.
After the completion of the reaction, the polymer was precipitated by pouring into a large amount of methanol, washed by filtration and dried under reduced pressure at 60 ° C. for 5 hours to obtain 30.5 g of polymer B.
The molecular weight of the obtained polymer as measured by GPC was Mn = 726,000 and the molecular weight distribution Mw / Mn = 1.51. ^{From the 1} H-NMR spectrum, it was confirmed that the composition ratio of the structure derived from monomer A and the structure derived from norbornene during polymerization was A / B = 46/54 (mol / mol).

Polymer Production Example 3: Synthesis of Tris (trimethylsiloxy) silylnorbornene-b-norbornene addition copolymer (Polymer C) In Polymer Production Example 2, the charge amounts of Monomer A and Monomer B were each set to a single amount. When an experiment was conducted in the same manner except that the body A was 44.7 g (0.115 mol) and the monomer B was 5.8 g (0.062 mol), 34.1 g of the polymer C was obtained. The molecular weight is Mn = 601,000, the molecular weight distribution Mw / Mn = 1.49, and the composition ratio of the structure derived from monomer A and the structure derived from norbornene during polymerization is A / B = 67/33 (mol / Mol).

Polymer Production Example 4: Synthesis of bis (trimethylsiloxy) methylsilylnorbornene-b-norbornene addition copolymer (Polymer D) In Polymer Production Example 2, instead of using monomer A, the following formula (13) is used. When an experiment was conducted in the same manner except that the monomer C was changed to 28.0 g (0.089 mol), 29.4 g of the polymer D was obtained. The molecular weight is Mn = 892,000, the molecular weight distribution Mw / Mn = 1.62, and the composition ratio of the structure derived from the monomer C during polymerization and the structure derived from norbornene is C / B = 46/54 (mol / Mol).

Polymer Production Example 5: Synthesis of Bis (trimethylsiloxy) methylsilylnorbornene-b-norbornene addition copolymer (Polymer E) In Polymer Production Example 4, the charge amounts of monomer C and monomer B were respectively An experiment was conducted in the same manner except that the monomer C was 36.2 g (0.115 mol) and the monomer B was 5.8 g (0.062 mol). As a result, 29.4 g of the polymer E was obtained. . The molecular weight is Mn = 724,000, the molecular weight distribution Mw / Mn = 1.38, and the composition ratio of the structure derived from the monomer C during polymerization and the structure derived from norbornene is C / B = 68/32 (mol / Mol).

Polymer production example 6: Synthesis of bis (trimethylsiloxy) methylsilylnorbornene addition polymer (polymer F) In polymer production example 4, instead of using monomer C and monomer B, monomer When an experiment was conducted in the same manner except that 55.7 g (0.177 mol) of C alone was used, 30.6 g of polymer F was obtained. The molecular weight was Mn = 632,000 and the molecular weight distribution Mw / Mn = 1.39.

Polymer production example 7: Synthesis of trimethylsiloxymethylphenylsilylnorbornene-b-norbornene addition copolymer (polymer G) In polymer production example 2, it is represented by the following formula (14) instead of using monomer A When an experiment was conducted in the same manner except that the monomer D was used and the monomer D was changed to 27.0 g (0.089 mol), 18.5 g of the polymer G was obtained. The molecular weight is Mn = 736,000, the molecular weight distribution Mw / Mn = 1.24, and the composition ratio of the structure derived from the monomer D during polymerization and the structure derived from norbornene is D / B = 49/51 (mol / Mol).

Polymer Production Example 8: Synthesis of Bis (trimethylsiloxy) methylsilylnorbornene-b-norbornene addition copolymer (Polymer H) In Polymer Production Example 7, the amounts of monomer D and monomer B charged were each An experiment was conducted in the same manner except that the monomer D was 34.8 g (0.115 mol) and the monomer B was 5.8 g (0.062 mol). As a result, 20.7 g of the polymer H was obtained. . The molecular weight is Mn = 479,000, the molecular weight distribution Mw / Mn = 1.32, and the composition ratio of the structure derived from the monomer D during polymerization and the structure derived from norbornene is D / B = 66/34 (mol / Mol).

Polymer Production Example 9: Synthesis of Bis (trimethylsiloxy) methylsilylnorbornene addition polymer (Polymer I) In Polymer Production Example 7, instead of using monomer D and monomer B, only monomer D was used. An experiment was conducted in the same manner except that .6 g (0.177 mol) was used, and 25.7 g of polymer I was obtained. The molecular weight was Mn = 467,000 and the molecular weight distribution Mw / Mn = 1.35.

(Preparation of asymmetric membrane)
Example 1
Polymer A was dissolved in a mixed solution of tetrahydrofuran (THF) and methanol to prepare a solution for preparing an asymmetric membrane. The composition of the solution was tetrahydrofuran / methanol / polymer A85 / 10/5% by mass.
A frame having a thickness of 180 μm is placed on a glass plate, and a mesh body (material: PET, opening ratio: 45%, opening diameter: 85 μm) is laid in the frame, and the above solution is cast on the thickness of the mesh body there. . Thereafter, it was dried at 25 ° C. for 2 seconds to form a dense layer on the surface layer portion. Next, when the whole was immersed in methanol as a coagulation solvent, a porous layer was formed on the glass plate side. That is, an asymmetric membrane (film thickness: 20 μm) having a porous layer and a dense layer was formed.

Example 2
In a solution for producing an asymmetric membrane, “NanoTek SiO ₂ ” (registered trademark, manufactured by CI Kasei Co., Ltd., no pores, particle size (center value): 25 nm, surface properties: hydrophilic) as silica particles is added to 100 parts by mass of polymer A An asymmetric membrane was prepared in the same manner as in Example 1 except that 100 parts by mass was added.

Example 3
An asymmetric membrane was prepared in the same manner as in Example 1 except that polymer B was used instead of polymer A.

Example 4
An asymmetric membrane was prepared in the same manner as in Example 1 except that the polymer C was used instead of the polymer A.

Example 5
An asymmetric membrane was prepared in the same manner as in Example 1 except that polymer D was used instead of polymer A.

Example 6
An asymmetric membrane was prepared in the same manner as in Example 1 except that polymer E was used instead of polymer A.

Example 7
An asymmetric membrane was prepared in the same manner as in Example 1 except that the polymer F was used instead of the polymer A.

Example 8
An asymmetric membrane was prepared in the same manner as in Example 1 except that polymer G was used instead of polymer A.

Example 9
An asymmetric membrane was prepared in the same manner as in Example 1 except that polymer H was used instead of polymer A.

Example 10
An asymmetric membrane was prepared in the same manner as in Example 1 except that polymer I was used instead of polymer A.

(Production of water surface deployment membrane)
Comparative Example 1
Polymer A was dissolved in toluene to prepare a solution for preparing a water surface spread membrane. The concentration of the polymer A was 5% by mass based on the total mass of the solution. This solution was deposited on a support isopore (manufactured by Nihon Millipore, material: polycarbonate, average pore size 0.22 μm) by a water surface development method, and then toluene and water were removed with a drier to obtain an average thickness of 0. A 1 μm membrane was obtained.

Comparative Example 2
Polymer C was dissolved in toluene to prepare a solution for preparing a water surface spreading film. The concentration of polymer C was 5% by mass based on the total mass of the solution. This solution was deposited on a support isopore (manufactured by Nihon Millipore, material: polycarbonate, average pore size 0.22 μm) by a water surface development method, and then toluene and water were removed with a drier to obtain an average thickness of 0. A 1 μm membrane was obtained.

Comparative Example 3
Polymer E was dissolved in toluene to prepare a solution for preparing a water surface spread membrane. The concentration of the polymer E was 5% by mass based on the total mass of the solution. This solution was deposited on a support isopore (manufactured by Nihon Millipore, material: polycarbonate, average pore size 0.22 μm) by a water surface development method, and then toluene and water were removed with a drier to obtain an average thickness of 0. A 1 μm membrane was obtained.

Comparative Example 4
Polymer H was dissolved in toluene to prepare a solution for preparing a water surface spreading film. The concentration of the polymer H was 5% by mass based on the total mass of the solution. This solution was deposited on a support isopore (manufactured by Nihon Millipore, material: polycarbonate, average pore size 0.22 μm) by a water surface development method, and then toluene and water were removed with a drier to obtain an average thickness of 0. A 1 μm membrane was obtained.

Comparative Example 5
Polymer F was dissolved in toluene to prepare a solution for preparing a water surface spread membrane. The concentration of the polymer F was 5% by mass based on the total mass of the solution. This solution was deposited on a support isopore (manufactured by Nihon Millipore, material: polycarbonate, average pore size 0.22 μm) by a water surface development method, and then toluene and water were removed with a drier to obtain an average thickness of 0. A 1 μm membrane was obtained.

<Evaluation of membrane>
(1) Confirmation of the presence or absence of pores About the asymmetric membrane obtained in the examples and the water surface development membrane obtained in the comparative example, the surface (the dense layer side for the asymmetric membrane) was observed with a scanning electron microscope (SEM). The presence or absence of holes was confirmed. The results are shown in Table 1. 12 is an SEM image of the asymmetric membrane of Example 6, and FIG. 13 is an SEM image of the water surface development membrane of Comparative Example 3.

(2) Gas (O ₂ and CO ₂ ) permeability (under equal pressure)
About the asymmetric membrane obtained in the examples and the water surface spread membrane obtained in the comparative example, using an isobaric gas permeability measuring device (manufactured by Denso, see gas permeability evaluation device in FIG. 14) under the following measurement conditions. The gas permeability coefficients P (O ₂ ) and P (CO ₂ ) for oxygen and carbon dioxide were measured. The obtained gas permeation coefficients P (O ₂ ) and P (CO ₂ ) are divided by the film thickness (L) of the membrane to calculate gas permeation rates R (O ₂ ) and R (CO ₂ ), and P (O ₂₎ was calculated P (except to separate ratio _{CO 2) α (= P (} O 2) / P (CO 2)). The results are shown in Table 1.

The initial environment in this evaluation apparatus is an initial concentration environment in which gas is introduced into an evaluation chamber from a cylinder (for example, oxygen concentration: 20.5%, carbon dioxide: 4000 ppm) in which oxygen and carbon dioxide concentrations are adjusted in advance. Had made. The outside of the evaluation chamber is atmospheric air (oxygen concentration: 20.8 to 20.9%, carbon dioxide: 400 to 600 ppm). The membrane installation part is provided with a partition plate (not shown), and the membrane is shut off from the outside air by the partition plate before the evaluation is started. Membrane evaluation was started by removing the partition plate of the membrane installation part under the following measurement conditions, and gas exchange was performed inside and outside the evaluation chamber. That is, the gas permeation rate for oxygen and carbon dioxide was measured from changes in the gas concentrations of the two components in the evaluation chamber. The flow direction of the target gas with respect to the film was an initial concentration environment in which oxygen flows from outside to inside and carbon dioxide flows from inside to outside. The oxygen and carbon dioxide concentrations inside and outside the evaluation chamber were measured with an oxygen sensor (manufactured by Chino, model number: MG1200) and a carbon dioxide sensor (manufactured by Vaisala, model number: GMP343), and data logger (manufactured by Chino, model number: Recorded in KIDS ver6).
<Measurement conditions>
Temperature: 23 ± 2 degrees Pressure difference between membranes: None Gas partial pressure difference between membranes: oxygen 0.0013 to 0.0066 atm, carbon dioxide 0.0001 to 0.0011 atm

(Under differential pressure)
For the asymmetric membrane obtained in the example and the water surface spread membrane obtained in the comparative example, the air permeation amount R (air) under the differential pressure of the membrane was measured using the apparatus shown in FIG. The results are shown in Table 1.

  This device includes a 7 L aluminum container (made by Denso) having a membrane mounting part for mounting a membrane, an air introducing part for introducing air into the container, and a pressure measuring part (pressure measurement) for measuring the pressure in the container. Meter) and an introduction air measurement unit (flow meter) for measuring the amount of air introduced into the container. The air introduction part should just be what can supply the air pressurized by the compressor etc. The pressure measurement unit is a part that performs evaluation by introducing air into a container in which a pressure gauge (manufacturer: Yokogawa Electric, name: digital manometer, model number: MT210) is installed (for example, 1 to 50 kPa). The introduction air measurement unit is a unit that measures a gas flow rate (for example, 1 to 200 sccm) at a certain arbitrary pressure (in a range of 1 to 50 kPa) using a mass flow meter (model 3100, manufactured by Cofrock). Note that it is preferable to change the combination of the pressure gauge and the mass flow meter depending on the resistance of the film, the strength of the film, etc. (especially when evaluation at 1 kPa or less is required).

The evaluation method is shown below. In this example, the procedure for measuring the pressure in the container when the flow rate is constant is described, but the reverse method may be used.
First, after attaching a membrane to the membrane mounting portion of the container, air was introduced into the container, and an arbitrary flow rate (1 to 200 sccm) was maintained. When the pressure in the container was stabilized, the discharge flow rate from the membrane under the pressure was regarded as the air flow rate at the introduction air measurement unit, and the air flow rate at that pressure was taken. The measurement was performed by gradually increasing from the lower air flow rate (for example, increasing by 1% with respect to full scale). The permeation rate (gas permeability) of the membrane was obtained by approximating the measurement points (for example, 5 points) obtained by the above method by the square method first, and calculating the permeation rate from the slope.

(3) Heat loss Using a reefer container under the following conditions as a model case, heat loss was calculated by using a ventilation filter. Note that this heat loss includes (a) O ₂ caused by concentration difference, CO ₂ exchange heat loss Q ₁ , (b) gas exchange heat loss Q ₂ caused by pressure difference, and (c) filter. it can be obtained as the sum of the heat loss Q ₃ due to heat transmission (heat conduction, heat transfer) from. Further, under the following conditions, the heat loss Q ₀ in the case of applying the conventional direct method, a 1.67kW as shown in the following formula. The heat loss (Q ₁ + Q ₂ + Q ₃ ) [W] when using a ventilation filter is preferably 20% or less, more preferably 10% or less of Q ₀ .
Q ₀ [W]
= Air specific gravity x Outside air volume x (Outside air specific enthalpy-Internal specific enthalpy) / (Unit conversion)
= Ρ [kg / m ³ ] × Q (air) [m ³ / min] × (h2-h1) [kJ / kg] × 16.6
= 1.293 x 1.6 x 48.7 x 16.6
= 1.67KW
<Conditions>
Container size: 12.0m x 2.4m x 2.9m (length x width x height)
Ventilation filter size: 1m x 1m
Outside air temperature T ₁ : 30 ° C
Inside air temperature T ₂ : 14 ° C.
O ₂ concentration difference ΔP (O ₂ ) between outside air and inside air: 9% (6.8 cmHg)
Difference in concentration of CO ₂ between outside air and inside air ΔP (CO ₂ ): 3% (2.3 cmHg)
Pressure difference ΔP between outside air and inside air: 100 Pa (0.1 kPa)

(A) Heat loss Q ₁ due to O ₂ and CO ₂ exchange caused by concentration difference
The heat loss Q ₁ due to O ₂ and CO ₂ exchange due to the concentration difference was calculated by the following formula. The results are shown in Table 1.
Q (O ₂ ) + Q (CO ₂ ) = R (O ₂ ) * △ P (O ₂ ) + R (CO ₂ ) * △ P (CO ₂ )
Q ₁ [W / m ² ] = Air specific gravity × Outside air flow rate × {(Outside air (30 ° C.) specific enthalpy) − (Inside air (14 ° C.) specific enthalpy)} × (Conversion constant)
= ρ × (R (O ₂ ) * △ P (O ₂ ) + R (CO ₂ ) * △ P (CO ₂ )) × (h2-h1) × (1/3)
= 1.293 x (Q (O ₂ ) + Q (CO ₂ )) x 48.7 x (1/3)

(B) Heat loss Q ₂ due to gas exchange caused by pressure difference
By the following equation was calculated heat loss Q ₂ by gas exchange due to the pressure difference. The results are shown in Table 1.
Q (air) = R (air) * △ P
Q ₂ [W / m ² ] = Air specific gravity × Outside air flow rate × {(Outside air (30 ° C.) specific enthalpy) − (Inside air (14 ° C.) specific enthalpy)} × (Conversion constant)
= ρ × (R (air) * △ P) × (h2-h1) × 16.6
= 1.293 × Q (air) × 48.7 × 16.6
(C) Heat loss Q ₃ due to heat transmission from the filter
Heat loss due to heat transmission from the filter _{Q 3} are a 80~125 [W / ^{m 2]} extent regardless of the type of filter.
(D) Total heat loss Q ₁ + Q ₂ excluding Q ₃ was calculated as the total heat loss. The results are shown in Table 1.

(4) Water vapor permeability About the asymmetric membrane obtained in the example and the water surface development membrane obtained in the comparative example, using the isobaric gas permeability measuring apparatus (manufactured by Denso) shown in FIG. The gas permeability coefficient P (H ₂ O) for water vapor was measured. The obtained gas permeation coefficient P (H ₂ O) was divided by the film thickness L of the film to calculate a gas permeation rate R (H ₂ O). The results are shown in Table 2.

  The initial environment in this evaluation apparatus is air in an environment bench (trade name: small environmental tester, manufacturer: Aspec, model number: SH-641) in advance at a temperature of 40 ° C. and a relative humidity of 92 to 95% rh. Was adjusted to create an initial concentration environment. The inside of the evaluation chamber was purged with dry air to a temperature of 40 ° C. and a relative humidity of 10% rh or less. The membrane installation part is provided with a partition plate (not shown), and the membrane is shut off from the outside air by the partition plate before the evaluation is started. Membrane evaluation was started by removing the partition plate of the membrane installation part under the following measurement conditions, and gas exchange inside and outside the evaluation chamber was performed.

That is, the flow direction of the target water vapor with respect to the film was an initial concentration environment flowing from the outside to the inside of the evaluation bench. The concentration of water vapor in the evaluation chamber was measured with a humidity sensor (manufacturer: Vaisala, model number: HMP77) and recorded in a data logger (manufacturer: Chino, model number: KIDS ver6). The humidity inside the environmental chamber (outside the evaluation chamber) was measured by a humidity sensor attached to the environmental bench. The water vapor permeability was measured from the change in the water vapor concentration in the evaluation chamber (for example, relative humidity 20 to 40% rh).
<Measurement conditions>
Temperature: 23 ± 2 degrees Pressure difference between membranes: None Relative humidity difference between membranes: Water vapor 82-85% rh

(5) Fine particle blocking property A layer to which a nanoparticle generator (made by Palas, model number: GFG-1000) is connected, and B layer to which a particle counter (made by TSI, model number: SMPS-3034) is connected Using a measuring apparatus (see FIG. 17) connected through a holder in which a membrane sample is set, the particle blocking property was measured by the following procedure. The results are shown in Table 1.
i) Carbon particles having a particle size of 10 to 500 nm are generated by a nanoparticle generator and stored in the A layer.
ii) A sample of an asymmetric membrane (water surface development membrane) is set in a sample holder (membrane area: maximum 16 cm ² ), the valve V1 between the sample holder and the B layer is closed, and the differential pressure between the A layer and the B layer is The B layer is depressurized until 1 kPa is reached.
iii) The valve V1 is opened, and carbon particles are supplied to the film by being put on a gas that permeates when the inside of the B layer returns to the atmospheric pressure, and the carbon particles that have passed through the film are stored in the B layer.
iv) The concentration of carbon particles in the B layer is measured using a particle counter.
v) The fine particle blocking property is calculated based on the following formula.
Fine particle blocking property [% by mass] = 100 × {(Cin−Cout) / Cin}
(Cin: particle concentration in the A layer [μg / mL], Cout: particle concentration in the B layer [μg / mL])

  Since the asymmetric membrane of the example has high gas permeability, low heat loss, and high particle blocking properties, the reefer container equipped with this asymmetric membrane can adjust the desired gas concentration with a simple configuration. And the heat load at the time of gas concentration adjustment can be made small. On the other hand, the water surface spreading membrane of the comparative example has low heat loss and high particle barrier properties, but has extremely low gas permeability. Therefore, it is difficult to exchange gas in a reefer container equipped with this water surface spreading membrane.

1 ... Reefer container, 3 ... porous layer, 5 ... dense layer, 10 ... housing, 11 ... inside air circulating blower, 12 ... _{O 2} sensor, 13 ... CO ₂ sensor, 14 ... humidity sensor, 20 ... ventilation filter unit , 21 ... flow path forming member, 22 ... outside air flow path, 23 ... inside air flow path, 24 ... ventilation filter, 25 ... outside air circulation blower, 26 ... inside air circulation blower, 26a ... blower fan, 26b ... motor, 26c ... drive Gear part, 27, 27a, 27b ... Inside air flow path switching door, 28 ... Outside air blower, 28a ... Blower fan, 28b ... Driven gear part, 29 ... Power transmission member, 29a ... Rotating shaft, 29b ... Inside air side gear part, 29c ... Outside air side gear part, 29d ... Fan, 30 ... Condenser, 31 ... Evaporator, 32 ... Outside air introduction passage, 33 ... Inside air circulation passage, 34 ... Partition wall, 35 ... Bypass passage, 36 ... Outside air passage type Member, 37 ... rib, 50 ... control unit, 100, 100a, 100b ... asymmetric membrane, 110a ... support, 110b ... support, 150a, 150b ... asymmetric membrane structure.

Claims (6)

A reefer container that is ventilated through a ventilation filter,
The ventilation filter is a reefer container including an asymmetric membrane formed of a polymer material obtained by polymerizing a monomer composition containing a monomer represented by the following formula (1).

(In the formula, R ¹ is independently an alkyl group having 1 to 12 carbon atoms and / or an aryl group having 6 to 10 carbon atoms, and X is a group represented by the following formula (i) and / or the following formula: (Ii) is a group represented by (ii), a is an integer of 1 to 3, and b is an integer of 0 to 2.

(R ² is each independently an alkyl group having 1 to 12 carbon atoms, d is an integer of 1 to 5, and c is an integer of 3 to 5.)   The reefer container according to claim 1, wherein the polymer material is an addition polymer obtained by addition polymerization of a monomer composition containing the monomer represented by the formula (1). The ratio of the oxygen permeability coefficient P (O ₂ ) and the carbon dioxide permeability coefficient P (CO ₂ ) of the asymmetric membrane under the condition of 23 ± 2 ° C. and no pressure difference between the membranes satisfies the following formula (3): Item 3. A reefer container according to item 1 or 2.
1.0 <P (O ₂ ) / P (CO ₂ ) <1.70 (3) The reefer container is present in a housing in which the temperature of the inside air existing therein is adjusted, gas concentration detection means for detecting a specific type of gas concentration in the housing, an outside air flow path through which outside air flows, and the inside of the housing A flow path forming member that forms an internal air flow path through which the internal air flows, and the external air flow path such that one surface is in contact with the external air in the external air flow path and the other surface is in contact with the internal air in the internal air flow path The ventilation filter disposed at the boundary between the internal air flow path, the air blowing means for generating at least one of the flow of outside air in the external air flow path and the flow of internal air in the internal air flow path, and air blowing by the air blowing means Control means for performing control,
The reefer according to any one of claims 1 to 3, wherein the control unit performs blowing control of at least one of outside air and inside air by the blowing unit based on the gas concentration detected by the gas concentration detecting unit. container. An inside air circulation blower for circulating inside air is provided in the housing,
The air blowing means for generating a flow of the internal air in the internal air flow path introduces the flow of the internal air generated by the internal air circulation blower into the internal air flow path, thereby generating the flow of the internal air in the internal air flow path. 4. Reefer container according to 4.   The air blowing means for generating the flow of the outside air in the outside air flow path and the flow of the inside air in the inside air flow path is different from the first blower fan provided in the inside air flow path or the outside air flow path. A second blower fan provided in the flow path, a drive unit that rotationally drives the first blower fan, and a power transmission member that transmits a rotational driving force of the drive unit to the second blower fan. Item 5. A reefer container according to item 4.