JPH10276611A - Containers for transporting aqueous organisms - Google Patents

Abstract

(57) [Summary] [Problem] To reduce the mortality without damaging live fish with a small amount of water without requiring large-scale equipment, and to transport, store or store from the production area or fish farm to the final consumer. The present invention provides a water-free transport container for water-based organisms that can be displayed on a display. In a container capable of being sealed in a liquid-tight manner, at least a part thereof is constituted by a breathable film such as a craze film, and the breathable film has an oxygen permeability (A) at 23 ° C. of 3 × 10 ³ cc. / M ² · 24hr to 1 ×
In the range of 10 ¹⁰ cc / m ² · 24 hr and at 40 ° C
Wherein the water vapor transmission rate (B) is 1 × 10 ⁶ g / m ² · 24 hr or less, and preferably (A) / (B) is 150 or more.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a container for transporting aqueous organisms such as live fish using a small amount of water.

[0002]

2. Description of the Related Art It is not easy to transport, preserve, or display live fish or crustaceans in a living state because these organisms are aqueous organisms. For example,
In order to transport live fish, it is ideal to maintain a state close to the environment where the fish live, and a large amount of water is required.However, a large amount of water must be carried, and transport efficiency is extremely high. It is bad and requires a lot of cost and labor. Therefore,
When transporting live fish, the amount of water carried must be as small as possible. However, if the amount of water used for transporting live fish is reduced, the live fish may be damaged by vibrations during transport, or the fish may die due to a decrease in underwater oxygen concentration or an increase in carbon dioxide gas concentration.

[0003] Various measures have been devised as a countermeasure. For example, as a method of preventing the fish from coming into contact with each other due to vibration during transportation or damaging each other, the commercial value of the live fish is reduced. (Japanese Patent Laid-Open Nos. 1-139386 and 4-3073)
7).

Further, in order to prevent fish from dying due to a decrease in oxygen concentration in water or seawater in a transport container or an increase in carbon dioxide concentration, a method of continuously replacing part of the water contained in the transport container ( JP-A-54-10199), a method of attaching an oxygen replenishing device (JP-A-50-110899, JP-A-53-2300, JP-A-60-6143), and a method of attaching a water circulating device and an air mixing device (Japanese Patent Application 59-22
7227), a method of coexisting with a carbon dioxide absorbent and a deodorant (JP-A-63-245628),
-48706). Furthermore, a method of storing and transporting fish in a pseudo-hibernation state (Japanese Patent Laid-Open No. 50-57)
900, JP-A-62-208225, JP-A-3-139
231) has also been proposed.

On the other hand, there is a simple transportation method using a plastic bag. For example, there is a method in which water and fish are put in a polyethylene bag, and the remainder is filled with oxygen or air and sealed. Although this method is indeed simple, there is no source of oxygen other than the encapsulated oxygen, which has severe limitations on the life of the fish. For the improvement, a method of packaging with a film made of a vinyl alcohol-based polymer (JP-A-4-3073)
7), a method using a gas permeable membrane made of a nonwoven fabric (Japanese Patent Laid-Open No. 3-195436) has been proposed. When a non-woven fabric is used, the non-woven fabric has an air permeability of 1 cc / cm ² /
It is considered that the water resistance is preferably not less than 10 cm and not less than 10 cm. However, even with this method, there is a problem with water resistance, especially liquid leakage, making it difficult to make a container with the nonwoven fabric itself, and making the container easy to handle that can be used consistently in the process of transportation, storage and display I couldn't do that.

[0006]

As described above, if an oxygen replenishing device or a circulating device is installed, a great deal of equipment costs are required, so that there is an economical problem. Although improved, it was not possible to completely prevent trauma to live fish. Further, the method using a plastic film or a nonwoven fabric also has problems in transportation efficiency, economy, and life-prolonging effect, and is not suitable for live display and sale in a store. On the other hand, due to the recent gourmet orientation, there is a desire for a consistent container that can be sold as it is to a final consumer from a production area to retailers and supermarkets without any change.

[0007] Under the present circumstances, the present invention reduces the mortality without damaging live fish with a small amount of water, and does not require large-scale equipment, and transports and preserves from the production area or fishery to the final consumer. Another object of the present invention is to provide a water-free biological transport container that can be displayed at a store.

[0008]

Means for Solving the Problems The present inventors have conducted intensive studies on a container for keeping fish alive for a long time in a small amount of water, and as a result, a part of a gas permeable film having a specific oxygen permeability and moisture permeability has been partially or partially formed. It was discovered that the use of all the containers provided a remarkable life-extending effect of live fish during transportation, storage and display, and completed the present invention. That is, the present invention provides a liquid-tightly sealable container, at least a part of which is formed of a gas permeable film, which has an oxygen permeability of 3 × 10 ^{3 at} 23 ° C.
1 × From ^{cc / m 2 · 24hr 10 10} cc / m 2 · 24h
r and the moisture permeability at 40 ° C. is 1 × 10
^A gist of the present invention is a container for transporting aqueous organisms having a weight of ⁶ g / m ² · 24 hr or less. The container of the present invention needs to be able to be sealed in a liquid-tight manner. A state in which the liquid content does not leak.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The container for transporting aqueous organisms of the present invention is at least partially constituted by a breathable film, and may be a bag-like container constituted entirely of a breathable film alone, or may be a water or seawater spill. For example, a container in which a part of a general container such as a metal or plastic box or can is replaced with a breathable film may be used. Specifically, for example, a breathable film is used for the lid of a box-shaped plastic container, and the plastic container is sealed with heat or an adhesive, or a packing is interposed to prevent water or seawater from leaking. Containers and a water tank used for transporting fresh fish by truck are provided with a lid made of a breathable film.

As the resin constituting the breathable film used in the container for transporting an aqueous organism of the present invention, conventionally known polyolefins such as polyethylene and polypropylene; polyesters such as polyethylene terephthalate, polybutylene terephthalate and polynaphthalene terephthalate; 6, a polyamide such as nylon-6,6; a fluorine-containing resin such as polyvinylidene fluoride, and a synthetic resin such as polystyrene. Among them, polyolefin resins are preferable, and specific examples include high-density or low-density linear polyethylene and polypropylene. Polyolefin resins are suitable because they are inexpensive, easy to mold and process, have excellent recyclability, are chemically stable, and do not harm fish. The polyolefin more preferably used as the resin for the breathable film of the present invention is polypropylene.

As the breathable film that can be used in the container of the present invention, a substantially transparent film is preferable. The term “substantially transparent” as used herein refers to a state where the state of the fish can be easily confirmed from the outside when the fish is put together with water or seawater in the container. However, when the material other than the breathable film constituting the container of the present invention is substantially transparent, the breathable film used is not necessarily required to be transparent, but the breathable film itself is as transparent as possible. It is preferred that

The gas permeable film constituting the whole or a part of the container of the present invention is a gas permeable film having an oxygen permeability (23 ° C.) of at least 3 × 10 ³ cc / m ² · 24 hr, preferably Is 1 × 10 ⁴ cc / m ² · 24
hr or more, more preferably 5 × 10 ⁴ cc / m ² · 24
hr or more of a breathable film is used. If the oxygen permeability is less than 3 × 10 ³ cc / m ² · 24 hr, the amount of diffusion of oxygen required for respiration of aquatic organisms in the container, for example, into a bag, is insufficient, and the mortality rate of fish is increased. On the other hand, a breathable film having an oxygen permeability exceeding 1 × 10 ¹⁰ cc / m ² · 24 hr is disadvantageous in terms of the stability of such a film production. In addition, when the oxygen permeability increases, the moisture permeability increases. Is generally large, for example, when the oxygen permeability is 1
If it exceeds × 10 ¹⁰ cc / m ² · 24 hr, the transpiration of the water or seawater enclosed in the container becomes remarkable. Become. Therefore, the breathable film used in the container of the present invention has an oxygen permeability at 23 ° C. of 3 × 10 ³ to 1 × 10 ¹⁰ cc / m ² · 24 h.
It is necessary to be within the range of r.

The breathable film which can be used for all or a part of the container of the present invention has a moisture permeability (40 ° C.) of 1%.
It is a breathable film having a moisture permeability of 10 ⁶ g / m ² · 24 hr or less, preferably 1 × 10 ⁵ g / m ² · 24 hr or less, more preferably 5 × 10 ⁴ g / m ² · 24 hr or less. Is used. Moisture permeability 1
If it exceeds × 10 ⁶ g / m ² · 24 hr, the water or seawater enclosed in the container will evaporate or leak, causing a problem in long-term transport and storage of fresh fish.

The air-permeable film that can be used in the present invention is not limited as long as it satisfies both the oxygen permeability and moisture permeability requirements as defined above. In particular, the oxygen permeability (A) and the moisture permeability (B ) Is preferably a breathable film having a ratio (A) / (B) of 150 or more. Here (A) /
(B) is determined by the balance between the ease of replenishing oxygen from outside the container to the inside of the container and the dissipation of water or seawater from the inside of the container to the outside of the container. is there. For example, if the oxygen permeability is the same, the larger the value is, the more the water or seawater from the inside of the container to the outside of the container is suppressed, which is preferable. Similarly, at the same moisture permeability, it is preferable that the larger the value is, the easier the supply of oxygen from the outside of the container to the inside of the container is.

[0015] The breathable film used in the container of the present invention comprises:
Selection is made in consideration of the balance between oxygen permeability and moisture permeability according to the shape and scale of the container.
It is desirably 50 or more, preferably 200 or more, and more preferably 500 or more. (A) /
If (B) is less than 150, water or seawater may escape from the inside of the container to the outside of the container, or the supply of oxygen from the outside of the container to the inside of the container may be insufficient. Satisfactory results may not always be obtained, such as the inability to maintain the desired shape when storing fresh fish or the like.

The air-permeable film that can be used for the container of the present invention can be used alone, of course.
Other members, such as a nonwoven fabric, a wire mesh, and another film are laminated, and the oxygen permeability (A) at 23 ° C. of the laminated film is 3 ×
From 10 ³ cc / m ² · 24 hours to 1 × 10 ¹⁰ cc / m ² ·
Those having a moisture permeability (B) at 40 ° C. of 1 × 10 ⁶ g / m ² · 24 hr or less can be used.

In the present invention, the oxygen permeability (A) at 23 ° C. is from 3 × 10 ³ cc / m ² · 24 hr to 1 × 1
The total surface area of the container for transporting aqueous organisms or the entire surface area thereof is determined by a breathable film having a moisture permeability (B) at 40 ° C. of 1 × 10 ⁶ g / m ² · 24 hr or less in a range of 0 ¹⁰ cc / m ² · 24 hr. Some are configured. When the breathable film is used for a part of the container, the oxygen permeability (A) in all areas where the container is in contact with the outside air is 3 × 10
³ cc / m ² · 24hr from ^{1 × 10 10 cc / m 2} · 24
hr, and the moisture permeability (B) at 40 ° C. is 1 ×
It is preferably 10 ⁶ g / m ² · 24 hr or less. For this purpose, taking into account the shape of the container and the characteristics of the breathable film used, the area (D) of the breathable film relative to the total surface area (C) of the container for transporting aqueous organisms, that is, the area ratio (D) / (C ) Is determined and used. The surface area referred to here is an area where the container for transporting an aqueous organism is in contact with an external air layer.

For example, when a breathable film having an oxygen permeability of 6 × 10 ³ cc / m ² · 24 hr is used for a part of a container having an oxygen permeability of substantially zero, the area ratio (D) /
In order to make (C) 0.5 or more and to make the area ratio 0.1, the oxygen permeability is 3 × 10 ⁴ cc / m ² · 24 hr.
It is necessary to use the above breathable film.

In the present invention, the oxygen permeability (A) is 3 ×
From 10 ³ cc / m ² · 24 hours to 1 × 10 ¹⁰ cc / m ² ·
A container for transporting an aqueous organism using a breathable film having a moisture permeability (B) of 1 × 10 ⁶ g / m ² · 24 hr or less at 40 ° C. in a range of 24 hours or less is 1 × 10 ⁶ g / m ² · 24 hours. At least 5%, preferably 10%, more preferably 15% of its total volume in the container
It is preferable to have a space above the liquid surface in which air or oxygen can be sealed. If the space is less than this, it is not possible to smoothly supply oxygen from the outside into the container, which is not preferable.

In the container for transporting an aqueous organism of the present invention,
Since the air or oxygen layer inside the container comes into contact with the outside air via the gas permeable film, gas exchange of oxygen, nitrogen, and carbon dioxide is mainly performed by a diffusion action. The characteristic of the breathable film used in the present invention is that, in a container for transporting aqueous organisms, a decrease in oxygen concentration due to consumption of oxygen and an increase in carbon dioxide gas concentration occur due to the life activity of fresh fish enclosed with water or seawater. Thus, even if the gas composition inside the container is different from the outside air (gas) composition, the gas permeable film acts as a permeable membrane to keep the gas composition inside and outside the container constant. In addition, the gas composition in the container is always constant as in the case of the external air composition, and the effect of extending the life of fresh fish is increased.

Further, a flexible bag-shaped container for transporting an aqueous living organism using a breathable film is produced as the container of the present invention,
When fresh fish is sealed together with water or seawater, the vapor pressure of the water in the bag rises to the saturated vapor pressure corresponding to the environment in which the bag is placed, and the oxygen and nitrogen concentrations inside the bag, that is, the amount of each gas The pressure is different from the atmosphere outside the bag, and oxygen and nitrogen flow from the outside through the film so that the gas permeable film acts as a permeable membrane to keep the gas partial pressure constant.
On the other hand, the internal water vapor also diffuses to the outside in order to keep the gas partial pressure with the outside constant. In this case, when the ratio (A) / (B) of the oxygen permeability (A) and the moisture permeability (B) of the gas permeable film used in the present invention is 150 or more, the permeability of water vapor is higher than that of oxygen and nitrogen. The speed is slow, resulting in a high gas pressure in the bag, which causes the flexible bag to swell permanently. As a result, it is possible to prevent the fresh fish sealed in the bag from being damaged, to reduce the stress of the fish, and to prevent the film from sticking to the fresh fish and obstructing the respiration of gills, which is preferable for transporting, storing and displaying the fresh fish.

If the ratio (A) / (B) of the oxygen permeability (A) to the moisture permeability (B) is less than 150, the bag-like container for transporting an aqueous organism is not sufficiently swelled, which is not preferable. If the degree is less than 3 × 10 ³ cc / m ² · 24 hr, it takes time to swell and 1 × 10 ¹⁰ cc / m ² · 24 h
r or the moisture permeability (B) is 1 × 10 ⁶ g / m ² · 2
If it exceeds 4 hours, the water in the bag or the seawater will evaporate violently and may not swell sufficiently.

The breathable film constituting at least a part of the container of the present invention can be produced by appropriately employing a conventionally known method.
Oxygen permeability (A) at 3 ° C. is 3 × 10 ³ cc / m ² · 2
It is in the range of 4 hr to 1 × 10 ¹⁰ cc / m ² · 24 hr, and the moisture permeability (B) at 40 ° C. is 1 × 10 ⁶ g / m ² ·
It is necessary to control so as to be 24 hours or less.

Known methods for producing a breathable film include:
For example, a method of forming pores by stretching a film at a specific temperature (Japanese Patent Application Laid-Open No. 63-152638,
-292143), a method of mechanically forming a hole with a slit or the like (JP-A-5-50539), a method of forming a hole using electric discharge, a method of forming a hole by solvent extraction, and the like. Among these methods for obtaining a breathable film, a method of locally bending a stretched film to produce a superfine striped craze (Japanese Unexamined Patent Publication No. 7-256676) has a range of air permeability. Can be changed arbitrarily and arbitrarily, the production is simple, and the transparency of the film is hardly impaired.
It is suitable as a method for producing a breathable film used as a container for transporting an aqueous organism.

The craze film of the polypropylene film can be produced, for example, as follows. In other words, by bending the support locally at the tip with an acute angle in parallel with the orientation direction of the film to the molecular orientation of the polypropylene film surface held in tension, and locally bending, by moving the bending deformation area, By forming a continuous striped craze in a direction perpendicular to the moving direction, a breathable film can be manufactured. A film in which the degree of orientation of the molecularly oriented film shows a birefringence of 0.5 × 10 ⁻³ or more is advantageous for easy formation of craze. The birefringence is a value defined in JP-A-7-256676.

The oxygen permeability of the breathable film having craze can be easily controlled by the amount of craze to be formed. Specifically, by selecting the degree of orientation of the film, the angle of the support contacting the film, the bending angle of the film, the degree of tension in the film when contacting the support, for example, the oxygen permeability is 1 × 10 ² -1 × 10 ⁹
It can be arbitrarily changed up to about cc / m ² · 24 hr, and the air permeability can be selected according to the activity of the aqueous organism.

The term “craze” as used herein includes a surface craze appearing on the film surface and an internal craze occurring inside, and refers to a region having a fine crack-like pattern. This craze is composed of molecular bundles (fibrils) and microvoids, and air permeability is secured in this portion. The craze film has very small microvoids, so there is no outflow of water or seawater, and since the size of the voids is smaller than the wavelength of light, light is not scattered and transparency is impaired. Has no features.

The container for transporting aqueous organisms of the present invention can be used as a container for transporting, storing and displaying most aqueous organisms as they are. For example, live fish such as sea bream, hamachi, sweetfish, and rainbow trout, soft-water aquatic organisms such as octopus, squid,
It is useful as a container for shellfish such as shrimp, oysters and abalone. In particular, transport and storage of live fish with high activity
Suitable for display. Further, when the living organism is sealed in the container together with seawater or water, oxygen gas may be supplementarily introduced instead of air, or an oxygen generating agent and a carbon dioxide gas absorbent may be used in combination.

[0029]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which, however, are not intended to limit the scope of the present invention.

Embodiment 1 Production of breathable film A: Using a craze film 1-465 mmφ uniaxial extruder, polypropylene (FL6CK) manufactured by Mitsubishi Chemical Corporation is melt-extruded at 250 ° C., and 3.5 mm at 135 ° C. in the longitudinal direction. Stretched twice,
165 ° C after stretching 10 times in the horizontal direction at 160 ° C
To obtain a transparent biaxially stretched film (1). The stretched film has a thickness of 30 microns and a birefringence of 21.
It was 5 × ^10-3 . Then, using a device shown in FIG. 1, a support (3) for craze generation having an edge (2) having a tip angle of 60 degrees on the surface of the stretched film (1).
In the lateral direction, and bent so that the bending angle (4) of the stretched film becomes 80 degrees, and the tension between the supporting rolls of (5) and (6) is 300 kg / cm ² (crazed film 1), 240 kg / Cm ² (craze film 2), 1
80 kg / cm ² (craze film 3), 60 kg
/ Cm ² (craze film 4) and 50m /
The film (7) in which continuous striped craze regions were generated in the horizontal direction was obtained by taking off at a speed of 1 minute. A craze film having a higher oxygen permeability can be produced as the tension is higher.

B: Crazy Film 5 Using the same apparatus as that for the above craze film, the same operation was conducted except that the tension between the supporting rolls was set to 250 kg / cm ^2, and polyvinylidene fluoride (trade name: Kyner 720, trade name: A craze film 5 was prepared from a stretched film of Atochem NA.

C: Solvent Extraction Films 6, 7 80 parts by weight of stearyl alcohol was powder-blended with 20 parts by weight of polyethylene having a viscosity average molecular weight of 1.5 million, and then kneaded at 170 ° C. Before the kneaded material solidified, a 0.5 mm press sheet was prepared, and then stearyl alcohol was removed by ethanol extraction. This sheet was stretched by a biaxial stretching machine to form a breathable film. The solvent-extracted films 6 and 7 were obtained by changing the stretching temperature.
Is a stretching temperature of 100 ° C.

Table 1 shows the characteristic values of the breathable films obtained by the above A to C. In this table, oxygen permeability is JIS
According to Z-1707, the moisture permeability is JIS K-7129
It measured according to (c method).

[0034]

[Table 1]

2. Preparation of Container for Transporting Aqueous Organisms A container for transporting aqueous organisms was prepared using the breathable film produced in the above item 1. The created containers are the following (1) to (3)
There are three types. That is, (1) is a rectangular bag (size: 100 mm × 80 mm, inner volume: 110 cm ³ ) made using the entire amount of the breathable film. (2) is a bag of the same size as (1), but using a breathable film on one side and a stretched polypropylene (PP) film before forming craze on the other side. (3) is a box-shaped PP plastic container (bottom size is 100 mm)
The air-permeable film is used for the lid part (× 100 mm, height 90 mm), and the area ratio of the air-permeable film to the entire surface area of the container is 18%.

3. Test Examples Test Examples 1 to 9 Tests were performed using live goldfish. Goldfish is 5cm long
, A healthy one with healthy movement. Containers (1) and (2) each contain 50 g of water, container 3 contains 250 g and goldfish one by one. Containers (1) and (2) are sealed by fusing and sealing. As for the container, the gas-permeable membrane was heat-sealed and sealed in a PP container. The sealed container was kept at 23 ° C. Some containers were vibrated for 1 minute once every 20 minutes, and the influence of vibration during transportation was also examined. Under such conditions, the survival state of the goldfish was examined by the time until death. In addition, newspaper was drawn under the container to check for water leakage in the container, and the wetness was checked. If there was even a little wetting, it was judged that there was a liquid leak. Further, for the bag-like containers (1) and (2), the state of swelling of the bag with the lapse of time was observed, and those with swelling were judged to be "swelling". Each test was performed at 5 points, and the results were averaged.
Table 2 shows the results.

Comparative Test Examples 1 to 3 For comparison, containers using a polyethylene film of the same thickness (Comparative Example 3) and a stretched PP film before forming a craze (Comparative Examples 1 and 2) instead of a breathable film Was prepared, and a test similar to the above-described test example was performed. Table 2 shows the results.

Comparative Test Example 4 A craze film similar to that used in Test Example 1 except that a craze film 4 having a small tension and a small oxygen permeability when forming craze was used. The test was performed and the results are shown in Table 2.

Comparative Test Example 5 A test was conducted in the same manner as in Test Example 1 except that the solvent extraction film 7 was used, and the results are shown in Table 2.

[0040]

[Table 2]

As is evident from Table 2, the container of the present invention has a surprisingly far surprising effect as a container for storing and transporting fish alive.

[0042]

The container for transporting aqueous organisms of the present invention does not require any special equipment for transporting live fish, does not require oxygen blowing during transportation, and can be transported with a small amount of water. Therefore, the live fish can be transported safely and economically. In addition, it is an epoch-making container that can be sold at stores as live fish in transport containers.

[Brief description of the drawings]

FIG. 1 is a schematic view of one embodiment of a method for producing a breathable film used in the present invention.

[Brief description of reference numerals]

 1: Stretched film 2: Edge 3: Support 4: Bending angle 5, 6: Support roll 7: Craze film

Claims (5)

[Claims] 1. A container capable of being sealed in a liquid-tight manner, at least a part of which is constituted by a gas-permeable film, said gas-permeable film having an oxygen permeability of 3 × 10 ³ c at 23 ° C.
from ^{c / m 2 · 24hr 1 ×} 10 10 cc / m 2 · 24hr
And the moisture permeability at 40 ° C. is 1 × 10 ⁶
g / m ² · 24 hr or less. 2. The air-permeable film has a ratio (A) / oxygen permeability (A) at 23 ° C. to moisture permeability (B) at 40 ° C.
The container for transporting an aqueous organism according to claim 1, wherein (B) is 150 or more. 3. The aqueous organism according to claim 1, wherein the breathable film is a craze film having an ultrafine striped craze formed by locally bending a stretched film. Shipping container. 4. A bag-like container which can be sealed in a liquid-tight manner, at least a part of which is constituted by a gas-permeable film, which has an oxygen permeability (A) of 3 at 23 ° C.
From × 10 ³ cc / m ² · 24 hr to 1 × 10 ¹⁰ cc / m ²
・ Moisture permeability at 40 ° C. in the range of 24 hours (B)
Is not more than 1 × 10 ⁶ g / m ² · 24 hr, and (A)
/ (B) is 150 or more, a bag-like container for transporting aqueous organisms. 5. A container capable of being sealed in a liquid-tight manner, at least a part of which is constituted by a gas-permeable film, and the ratio (D) / (C) of the area (D) of the gas-permeable film to the total surface area (C) of the container. ) Is 0.1 or more, the container for transporting aqueous organisms according to any one of claims 1 to 3.