JP2007290770A - Low-temperature insulating container - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a low-temperature insulating container having a heat insulating layer constituted of a strip-like plate foam containing a paper component and a resin component built therein which is capable of enhancing heat insulating performance and preventing the upper surface thereof from being swollen in a drum shape by the restoring force of the heat insulating layer. <P>SOLUTION: A double heat insulating layer is formed on the inner side of an outer box 10 by folding plate foams 20, 30 and 40, preferably over the entire surface. After a plate member 50 is arranged on the plate foam with an upper open surface, lids 16-19 are closed. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a cold storage container, and more particularly to a cold storage container suitable for storing and storing Christmas decoration cakes, ice creams and the like for a long period of time.

  As a cold storage container used in the above fields, a cold storage container including a shape-retaining outer box and a heat insulating layer accommodated therein is known. As a material constituting the heat insulating layer, a foamed resin such as expanded polystyrene is often used from the viewpoint of high heat insulation and light weight.

  In recent years, a new type of heat insulating material has been proposed, and Patent Document 1 or Patent Document 2 describes the new heat insulating material and a cold box that incorporates the heat insulating material as a heat insulating layer. This heat insulating material is a sheet-form foam composed of a paper powder component or a vegetable powder component, a starch component, and a resin component, and more specifically, 10 to 40% by weight of paper powder of government-made postcard paper or general wastepaper It is a plate-like foam composed of a component or vegetable powder component, 25 to 40% by weight starch component as an auxiliary agent, and 35 to 50% by weight polyolefin resin component, and the cold box covers the inside of the outer box The plate-like foam cut into a size is built in as a heat insulating layer so as to cover the inner surface of the outer box, and the inside of the heat insulating layer in the box shape is used as a cold insulation gap. This type of cold storage container has an advantage that the plate-like foam forming the heat insulating layer together with the outer box can be incinerated as general waste.

Japanese Patent No. 3323481 JP 2005-132470 A

  According to the description in Patent Document 1, for example, the plate-like foam is obtained by kneading a paper powder component and a starch component together with a polypropylene resin component, and extruding it with an extruder using water as a foaming medium. Can be obtained. Like a molded product made of foamed resin such as foamed polystyrene, it cannot be integrally molded into a box shape, and as described in Patent Documents 1 and 2, a plurality of plate shapes cut into a size covering the inside of the outer box The foam is assembled so as to cover the inner surface of the outer box to form a heat insulating layer, and the inside is used as a cold insulation gap. Therefore, a gap is easily formed between the contact surfaces of the plate-like foams in the heat insulating layer, and it is difficult to maintain high heat insulating properties for a long time.

  The present invention has been made in view of the above circumstances. For example, a sheet foam described in Patent Document 1 or 2 or a plate-like foam made of a vegetable powder component, a starch component, and a resin component is used as a heat insulating layer. An object of the present invention is to provide a cold storage container that can maintain high heat insulation for a long time.

  The cold insulation container according to the present invention comprises a shape-retaining outer box and a heat insulation layer, and the heat insulation layer is a cold insulation container in which a plate-like foam containing a paper component and a resin component is used. The cold storage container is further provided with a plate member that is built in the outer box in a bent posture and that can cover the upper open surface.

  In the present invention, “a plate-like foam containing a paper component and a resin component” constituting the heat insulating layer is a plate-like foam produced by the same method as described in Patent Document 1 or Patent Document 2 described above. In this specification, it may be simply referred to as “plate-like foam”. Examples of such plate-like foams include “Wonder Board” (trade name) manufactured by Tokiwa Printing Co., Ltd.

  In the cold storage container according to the present invention, the plate-like foam obtained by extrusion foaming is accommodated in an outer box having shape retention in a folded position without being cut into small pieces to form a heat insulating layer. Therefore, compared with the case where the cut thing is assembled as a heat insulation layer, the number of the gaps formed in the heat insulation layer can be reduced, and the heat insulation performance is improved.

  The plate-like foam described above has a relatively large restoring force after being bent. Therefore, when the plate-like foam is built in the outer box in the folded position as described above and the lid is closed, even if the lid is held down with a surface adhesive tape or the like, if left for a long time, The upper surface of the shape-retaining outer box gradually swells like a drum. When such a bulge occurs, the stacked posture becomes unstable when the cold storage containers are stacked in multiple stages, so it is necessary to prevent the bulge from occurring.

  For this purpose, the cold storage container according to the present invention further includes a plate member that can cover the upper open surface of the outer box having shape retention. It is desirable that the size of the plate member is a size that covers the entire surface of the upper open surface, but if the size covers about 50 to 80% of the open surface around the center, the intended purpose is achieved. can do. In the experiments of the present inventors, as shown in a later embodiment, the bulge is generated by closing the lid in a state where the plate-like member is arranged on the folded plate-like foam. Was almost completely suppressed. As a result, even when stacked in multiple stages, a stable stacking posture could be maintained over a long period of time. The plate member can be made of any material provided that it has a certain degree of bending resistance, such as paper material, wood material including plywood, resin material, and metal material. In consideration of the incineration process at the time of disposal, a paper material or a wood material including plywood is a preferable material.

  In the cold storage container according to the present invention, the outer box having shape retention can be made of any material including resin products, but a paper product, particularly a cardboard box, is a plate-like foam constituting the heat insulating layer. It is preferable because it can be incinerated as general waste with the body.

  In the cold storage container according to the present invention, the upper open surface of the outer box can be double-covered by folding both ends in the longitudinal direction of one strip-shaped plate-like foamed body from the left and right sides, and is folded. It is a preferable aspect that the lid is closed in a state where the plate-like member is disposed on the uppermost plate-like foam.

  In this aspect, the upper surface open portion of the outer box is covered twice, and no gap is formed even on the upper open surface side, so that further heat insulation is improved. On the other hand, since the plate-like foam has a relatively large restoring force after being bent as described above, when the open surface side is covered with the plate-like foam in a doubled state, the above-described bulge is generated. Although it becomes easy to occur, the bulge can be reliably suppressed by further providing a plate member that can cover the upper open surface of the outer box.

  If the outer box with shape retention is a cardboard box, storing the cold storage containers in the cold storage for a long period of time in a stacked state reduces the strength of the outer box due to moisture, and the stacked state May become unstable. In order to avoid this, it is preferable to impart water resistance to the corrugated cardboard box, so that long-term storage in the cool box can be performed with peace of mind. The provision of water resistance to the corrugated cardboard box may be formed from a corrugated cardboard having water resistance from the beginning, or may be performed by applying a water resistant spray or the like after forming the outer box.

  The cold storage container according to the present invention can be effectively used not only as a food such as a decoration cake and ice cream, but also as a storage container for medical products that need to be frozen. If necessary, an appropriate refrigerant is also housed inside the cold-reserved article.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to maintain high heat insulation for a long time in the cold storage container which formed the heat insulation layer with the plate-shaped foam containing the paper component and resin component which can be incinerated as general garbage. In addition, stability when stacked can be maintained for a long time.

  Hereinafter, the present invention will be described based on embodiments with reference to the drawings. FIG. 1 shows an example of a plate-like foam containing a paper component and a resin component used as a heat insulating layer in a cold insulation container according to the present invention. FIG. 2 is a cross-sectional view of one embodiment of the cold storage container according to the present invention, showing a state before the lid is closed. 3 is an exploded perspective view showing the cold insulation container shown in FIG.

  The plate-like foam A containing the paper component and the resin component used in the cold insulation container B according to the present invention has a long strip shape as shown in FIG. 1 and is used by cutting to a required length. As described above, the plate-like foam A is, for example, as described in Patent Document 1, 10 to 40% by weight of the paper powder component or vegetable powder component of government-made postcard waste paper or general waste paper, and 25 to 25 as an auxiliary agent. It can be obtained by extruding a kneaded product composed of 40% by weight starch component, 35-50% by weight polyolefin resin component and water from an extruder.

  The cold insulation container B according to the present invention includes an outer box 10 having shape retention, a heat insulating layer composed of the plate-like foam A, and a plate member 50 placed on the uppermost surface of the heat insulating layer when the lid is tightened. The The plate-like foam A is cut to a required length to form a strip-like plate-like foam, which is accommodated in a posture folded inside the outer box 10 and forms a heat insulating layer. Then, the lid of the outer box 10 is closed with the plate member 50 placed thereon.

  In this example, the outer box 10 is a corrugated cardboard box that has been subjected to a water-resistant treatment having a size of a (width) × b (depth) × h (height) with the lid closed, as shown in FIG. The bottom surface 11, four-circumferential side walls 12 to 15, and lid portions 16 to 19 integrally formed to bendable on the upper edge of each side wall. For example, one of the opposing lids 17 and 19 is first folded inward, and then the remaining opposing lids 16 and 18 are folded inward on the lids 17 and 19 folded inward. As a result, the outer box 10 is closed. After the lid is tightened, the lid is prevented from opening by attaching an adhesive tape to the joint between the lid portions 16 and 18.

  In this example, the heat insulation layer is composed of three types of the strip-like plate-like foams 20, 30, and 40 having different lengths. As shown in FIG. 3, the first strip-like plate-like foam 20 has a width of about a and a length of about 3a + 2h. The second strip-like plate-like foam 30 has a width of approximately a and a length of approximately a + 2h. The third belt-like plate-like foam 40 has a height of approximately h and a length of approximately 4a. First, while folding the first strip-shaped plate-like foam 20, it is put into the outer box 10 with the lid open, and then the second strip-like plate-like foam 30 is put on it while folding it. Further, the third belt-like plate-like foam 40 is put on the top while bending it.

  When the first band-like plate-like foam 20 having the above length is put into the outer box in contact with the bottom surface 11 of the outer box 10 and the inner surfaces of the left and right side walls 12 and 14, both ends in the longitudinal direction 21a and 21b protrude from the upper edge of the side wall of the outer box 10 by the length a. Next, the second belt-like plate-like foam 30 is put into the outer box in contact with the bottom surface of the first belt-like plate-like foam 20 and the inner surfaces of the other side walls 13 and 15 of the outer box 10. Then, the third strip-like plate-like foam 40 is inserted in a state of being folded into a square as shown in FIG. Thereby, the heat insulation layer which the plate-shaped foam A laminated | stacked twice is formed in the bottom face 11 of the outer case 10, and the inner surface of the four side walls 12-15. And the formed heat insulation layer does not substantially have a break that causes heat insulation failure.

  In the state where the three strip plate-like foams 20, 30, and 40 are put in the outer box 10 as described above, the containing article C to be kept cold is put. If necessary, add an appropriate refrigerant. Thereafter, both longitudinal ends 21a and 21b protruding from the upper edge of the side wall of the outer box 10 by the length a in the first strip-like plate-like foam 20 are folded inward. In the example shown in FIG. 3, the end 21a is bent first, and then the end 21b is bent. Thereby, the upper open surface of the outer box 10 is also double-covered by the plate-like foam.

  Next, the above-described plate member 50 is placed on the bent end portion 21b, the lid portions 17 and 19 are folded thereon, and the lid portions 16 and 18 are further folded thereon. Finally, a surface adhesive tape is applied to the joint between the lid portions 16 and 18 to suppress the lid, thereby preventing the lid portions 16 and 18 from opening. Thereby, since the cold storage container B will be in the closed state, it will be stored in the appropriate cold storage box in a stacked state, and delivered to the store when necessary.

  The three belt-like plate-like foams 20, 30, and 40 are made of the plate-like foam A containing the paper component and the resin component described above, and have a restoring force to return to the original posture from the folded state. Yes. Therefore, in particular, the portions 21a and 21b that are bent inward, which are both ends of the first strip-like plate-like foam 20, tend to bulge upward, and the upper surface of the cold insulation container tends to be drum-shaped. As shown in the embodiment, in the cold storage container B according to the present invention, the lid is closed in a state where the plate-like member 50 is disposed on the folded uppermost plate-like foam 21b. Almost no swelling can be suppressed. Thereby, even when stacked in multiple stages, the posture can be stabilized over a long period of time.

  In the above embodiment, the three heat insulating layers 20, 30, and 40 are used to form double heat insulation layers on all inner surfaces of the outer box 10. In a preferred form, the plate-like foam is housed in the outer box in an appropriately folded posture, so that the cold insulation space enclosed by the plate-like foam, that is, surrounded by the heat insulating layer, is inside the outer box. The shape of the plate-like foam is arbitrary on the condition that it is formed. Whatever form of plate-like foam is used, the above-mentioned plate member 50 is placed on the plate-like foam covering the upper open surface of the outer box, and the lid portion is folded to keep the cold. Container B is in a closed state. Even in that case, the presence of the plate member 50 can prevent the lid portion from bulging in a drum shape.

  Hereinafter, the present invention will be described with reference to examples and comparative examples.

[Example 1]
A comparative test was conducted on the heat insulation properties when the heat insulating layer was built in the outer box in a state where the plate-like foam was bent and when the heat-insulating layer was formed by cutting the plate-like foam.

  The cold insulation container demonstrated based on FIGS. 1-4 was manufactured. A corrugated cardboard box is used as the outer box 10 and the dimensions are 340 × 320 × 370 (height) mm. For the three types of strip-like plate-like foams 20, 30, and 40, a plate-like foam A (trade name: Wonderboard, manufactured by Tokiwa Printing Co., Ltd.) containing a paper component and a resin component having a thickness of 20 mm is used, and the total thickness is 40 mm. The heat insulation layer was formed. As the plate member 50, a cardboard having a size of 330 × 310 mm and a thickness of 3 mm was used.

  1 kg of water and 3 kg of a regenerator as the stored article C are filled in the space in the heat insulating layer, and both longitudinal ends 21 a and 21 b are protruding from the upper edge of the side wall of the outer box 10 in the first strip-like plate-like foam 20. Were folded inward to form a double heat insulation layer. The plate member 50 is placed thereon, the lid portions 17 and 19 are folded thereon, the lid portions 16 and 18 are further folded thereon, and a surface adhesive tape is applied to the joint between the lid portions 16 and 18. The lid was held down to obtain a closed cold container B.

  The cold container B was left in a constant temperature room at an environmental temperature of 60 ° C. for 24 hours, and the temperature change of 1 kg of water as the contained article C was followed. The water temperature at the start of the test was 15 ° C. The results are shown in the graph of FIG. 4 as-■-Examples.

[Comparative Example 1]
The outer box 10 used was the same outer box as in Example 1. The heat-insulating layer is obtained by cutting the same strip-shaped foam (product name: Wonderboard, manufactured by Tokiwa Printing Co., Ltd.) as used in Example 1 into the size of the bottom surface, four side surfaces, and the upper open surface of the outer box. Then, the cut plate-like foam was arranged so as to have a two-layer structure on all surfaces to form a heat insulating layer.

  After forming a heat insulating layer on the bottom surface and the four side surfaces, as in the case of Example 1, 1 kg of water and 3 kg of a cold storage agent are filled as the containing article C to fill the space in the heat insulating layer, and the sheet foam is cut on top Were laminated in two layers. The plate member 50 is placed thereon, the lid portions 17 and 19 are folded thereon, the lid portions 16 and 18 are further folded thereon, and a surface adhesive tape is applied to the joint between the lid portions 16 and 18. The lid was held down to obtain a closed cold container.

  The cold container was placed in the same environment as in Example 1, and the temperature change of 1 kg of water, which is the contained article C, was tracked for 24 hours. The results are shown in the graph of FIG. 4 as-□-comparative example.

[Discussion]
As shown in the graph of FIG. 4, the heat insulating container according to the present invention has a higher heat insulating performance than that of the comparative example. This is because the heat insulation layer was formed inside the outer box with the plate-like foam folded, so that compared to the case of making the heat insulation layer by gathering individually cut pieces, This is a result of reducing the number.

[Example 2]
The stability when stacking cold containers was tested.

  Four cold storage containers B adjusted in the same manner as in Example 1 were stacked in the vertical direction and left as they were for 1 hour. Then, when the clearance gap formed between the stacked cold storage containers B was measured and the average value was calculated | required, it was 7 mm. In addition, the four-tiered state maintained the stable state at the start of the stacking.

[Comparative Example 2]
Except that the plate member 50 was not used, the cold insulation containers were adjusted in the same manner as in Example 1, stacked in the same manner, and the measurement of the gap and the stability were tested. The gap was 15 mm on average, and the four-stacked state was unstable because it was shaken from side to side just by pushing slightly.

[Discussion]
From this, in the cold storage container according to the present invention, it is understood that the use of the plate member that can cover the upper open surface of the cold storage container when closing the lid greatly contributes to the stability when stacked. .

The figure which shows an example of the plate-shaped foam containing the paper component and resin component which are used as a heat insulation layer with the cold storage container by this invention. It is sectional drawing which shows one form of the cold storage container by this invention, and has shown the state before closing a cover part. The perspective view which decomposes | disassembles and shows one form of the cold storage container by this invention. The graph which compared the heat insulation of the cold storage container.

Explanation of symbols

  A ... Plate-like foam, B ... Cold storage container, C ... Packaged article, 10 ... Outer box with shape-retaining property, 11 ... Bottom, 12-15 ... 4 side walls, 16-19 ... Lid, 20, 30 , 40... First to third strip-like plate-like foams, 21a, 21b... Both ends in the longitudinal direction of the first strip-like plate-like foam 20, 50.

Claims (3)

It consists of a heat-retaining outer box and a heat-insulating layer, and the heat-insulating layer is a cold storage container in which a plate-like foam containing a paper component and a resin component is used,
The said heat insulation layer is incorporated in the outer case inside the attitude | position which bent the plate-shaped foam, and the cold storage container is further equipped with the board member which can cover an upper open surface, The cold storage container characterized by the above-mentioned.   The upper open surface of the outer box can be double-covered by folding both ends in the longitudinal direction of the single plate-like foam inward from the left and right, and the uppermost plate-like foam is folded. The cold storage container according to claim 1, wherein the lid is closed with the plate-like member disposed thereon.   The cold storage container according to claim 1 or 2, wherein the outer container having shape retention is a cardboard box having water resistance.

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