JPWO2014132661A1 - Insulated container - Google Patents

Abstract

The heat insulating container (104, 124, 134, 144) according to the present invention is used to hold a low-temperature substance stored at a temperature lower than room temperature, and the container housing (110, 124, 134, 144), And a heat insulating structure (105, 125, 135, 145) disposed outside the container housing (110, 124, 134, 144). The heat insulating structures (105, 125, 135, 145) are provided in order from the container housing (110, 124, 134, 144) to the outside, the first heat insulating layer (111), the second heat insulating layer (112). , And a third heat insulating layer (113), and the third heat insulating layer (113) includes a plurality of vacuum heat insulating materials (20A, 20B, 20C).

Description

  The present invention relates to a heat insulating container including a vacuum heat insulating material, and more particularly to a heat insulating container that can hold a low-temperature substance having a temperature lower than normal temperature, such as liquefied natural gas or hydrogen gas.

  For example, a combustible gas such as natural gas or hydrogen gas is a gas at room temperature, and therefore is liquefied and stored in a heat-insulating container during storage or transportation. Therefore, it can be said that the liquefied combustible gas is a low-temperature substance (more specifically, a low-temperature fluid) significantly lower than normal temperature.

  If natural gas is exemplified as such a substance, a typical example of a heat insulating container for holding liquefied natural gas (LNG) is an LNG storage tank installed on land, a tank of an LNG transport tanker, or the like. . These LNG tanks are required to maintain the heat insulation performance as much as possible because LNG needs to be held at a temperature that is 100 ° C. lower than normal temperature (the temperature of LNG is usually −162 ° C.).

  By the way, a vacuum heat insulating material using a fibrous core material made of an inorganic material is known as one of heat insulating materials having higher heat insulating performance. A general vacuum heat insulating material includes a configuration in which the core material is sealed in a vacuum-sealed state inside a bag-shaped outer packaging material having gas barrier properties. As an application field of the vacuum heat insulating material, for example, home appliances such as a household refrigerator, commercial refrigeration equipment, a heat insulating wall for a house, and the like can be given.

  Furthermore, recently, further improvement of the heat insulating performance of the vacuum heat insulating material has been studied. For example, as shown in Patent Document 1, the applicant of the present application forms a sealed portion having a plurality of thin-walled portions and thick-walled portions by thermally welding a multilayer laminate film that is an outer packaging material (a jacket material). We propose a vacuum insulation material with a structure. Thereby, compared with the structure which provides only a thin part, it can suppress that external air penetrate | invades in the inside of an outer packaging material with time. Therefore, the vacuum heat insulating material having the sealing portion can realize excellent heat insulating performance over a long period of time.

  If such a vacuum heat insulating material is applied to a heat insulating container such as an LNG tank, it is expected to effectively suppress the intrusion of heat into the heat insulating container. In the case of an LNG tank, generation of boil-off gas (BOG) can be effectively reduced if heat intrusion can be suppressed, and the natural vaporization rate (boil-off rate, BOR) of LNG can be effectively reduced. . As an example of applying the vacuum heat insulating material to the LNG tank, for example, a heat insulating structure of a low temperature tank disclosed in Patent Document 2 can be cited.

WO2010 / 029730A1 brochure JP 2010-249174 A

  In the field of heat insulating containers such as LNG tanks, the use of a vacuum heat insulating material as a heat insulating material is hardly known to the extent that the technique disclosed in Patent Document 2 is found. Here, as a result of intensive studies by the present inventors, in the heat insulating container to which the vacuum heat insulating material is applied, the following problems have been found in order to further improve the heat insulating performance.

  First, as a first problem, there is a point of suppressing heat transfer from between adjacent vacuum heat insulating materials.

  For example, the vacuum heat insulating material is used as a heat insulating panel whose periphery is coated with rigid polyurethane foam (molded integrally with the rigid polyurethane foam). By disposing the heat insulating panel adjacently so as to cover the outside of the container housing, a heat insulating layer (vacuum heat insulating layer) including a vacuum heat insulating material can be formed. That is, hard polyurethane foam exists in the gap between the vacuum heat insulating materials, but the heat insulating performance of the hard polyurethane foam is inferior to that of the vacuum heat insulating material. Therefore, heat transfer into the container housing can be effectively suppressed (or blocked) in the portion where the vacuum heat insulating material exists, but heat transfer cannot be effectively suppressed in the gap between the vacuum heat insulating materials (rigid polyurethane foam).

  In particular, when the temperature difference between the inside of the container housing and the outside air is large, a relatively large amount of heat transfer occurs from the rigid polyurethane foam in the gap. In this case, the high heat insulation performance by the vacuum heat insulating material may be substantially offset by heat transfer in the gap.

  Next, as a second problem, the outer packaging material (coating material) of the vacuum heat insulating material is embrittled by the influence of a low-temperature substance held inside the container housing.

  For example, a heat insulating layer made of a phenol foam heat insulating panel (phenol foam panel) is often interposed between the container housing and the vacuum heat insulating layer. Since the heat insulation performance of phenol foam is inferior to that of a vacuum heat insulating material, cold temperature (low heat) from a low-temperature substance held in the container case is conducted through the phenol foam panel and leaks to the vacuum heat insulating layer. Thereby, the temperature of the multilayer laminate film which is the outer packaging material of the vacuum heat insulating material is also greatly reduced. In particular, since the cold temperature is likely to leak from the joint portion between the phenol foam panels, the vacuum heat insulating material located at the joint portion is more easily cooled than the vacuum heat insulating material located at the other portion.

  When the multilayer laminate film is significantly cooled, the mechanical strength is lowered and it is easily embrittled. Therefore, the embrittlement progresses with time, and the multilayer laminate film may be cracked. If a crack occurs in the outer packaging material, the pressure inside the vacuum heat insulating material increases, so that the heat insulating performance is significantly lowered. Furthermore, as described above, in the case where the vacuum heat insulating material is integrally formed with the rigid polyurethane foam, the multilayer laminate film is stretched and stretched by heat shrinkage of the rigid polyurethane foam. If this tension expansion and contraction is repeated, cracks are likely to occur in the embrittled multilayer laminate film. Therefore, it becomes difficult to maintain the heat insulating performance of the vacuum heat insulating material for a long period of time.

  Next, a third problem is that the vacuum heat insulating material itself warps and deforms.

  For example, as described above, if the vacuum heat insulating material is a board-like heat insulating panel integrally formed with the hard polyurethane foam, the heat insulating panel is different due to the difference in thermal shrinkage between the hard polyurethane foam and the vacuum heat insulating material. There is a risk of warping and deformation. When the heat insulating panel is warped and deformed, a gap is likely to be generated between the heat insulating panels. As a result, heat transfer from the gap is increased, and the heat insulating performance of the entire vacuum heat insulating layer is deteriorated.

  The present invention has been made to solve such problems, and in a heat insulating container to which a vacuum heat insulating material is applied, while further improving the heat insulating performance, the heat insulating performance can be improved over a long period of time. The purpose is to realize it effectively.

  In order to solve the above-mentioned problems, the heat insulating container according to the present invention is used to hold a low-temperature substance stored at a temperature lower than normal temperature, and is disposed outside the container housing and the container housing. A heat insulating structure, and the heat insulating structure is a multilayer structure including a first heat insulating layer, a second heat insulating layer, and a third heat insulating layer, which are sequentially provided from the container housing toward the outside. The third heat insulating layer has a plurality of vacuum heat insulating materials.

  Although the specific structure of the vacuum heat insulating material used for the said heat insulation container is not specifically limited, The structure which has an explosion-proof structure which suppresses or prevents the rapid deformation | transformation of the said vacuum heat insulating material may be sufficient.

  The above object, other objects, features, and advantages of the present invention will become apparent from the following detailed description of the preferred embodiments with reference to the accompanying drawings.

  In the present invention, with the above configuration, in the heat insulating container to which the vacuum heat insulating material is applied, while further improving the heat insulating performance, it is possible to effectively realize a good heat insulating performance over a long period of time. Play.

FIG. 1A is a schematic diagram showing a schematic configuration of a spherical independent dunk type LNG transport tanker including a spherical tank that is a heat insulating container according to Embodiment 1 of the present invention, and FIG. It is a schematic diagram which shows schematic structure of the spherical tank corresponding to an arrow cross section. It is a fragmentary sectional view showing typically an example of composition of a heat insulation structure of a heat insulation container with which a spherical tank shown in Drawing 1B is provided. It is typical sectional drawing which shows the typical structure of the vacuum heat insulating material used for the heat insulation structure shown in FIG. It is a fragmentary sectional view which shows typically the other structural example of the heat insulation structure shown in FIG. FIG. 5 is a partial cross-sectional view schematically showing still another configuration example of the heat insulating structure shown in FIG. 2. It is a fragmentary sectional view which shows typically the structural example of the heat insulation structure with which the heat insulation container which concerns on Embodiment 2 of this invention is provided. It is a fragmentary sectional view which shows typically the other structural example of the heat insulation structure shown in FIG. FIG. 7 is a partial cross-sectional view schematically showing still another configuration example of the heat insulating structure shown in FIG. 6. FIG. 7 is a partial cross-sectional view schematically showing still another configuration example of the heat insulating structure shown in FIG. 6. It is a typical fragmentary sectional view which shows the structural example of the vacuum heat insulating material used for the heat insulation container which concerns on Embodiment 3 of this invention. It is a fragmentary sectional view showing typically the example of composition of the heat insulation structure with which the heat insulation container concerning Embodiment 4 of the present invention is provided. It is a fragmentary sectional view showing typically the example of composition of the heat insulation structure with which the heat insulation container concerning Embodiment 5 of the present invention is provided. FIG. 13A is a schematic cross-sectional view showing a configuration example of a vacuum heat insulating material used in the heat insulating container according to Embodiment 6 of the present invention, and FIG. 13B is a view of a sealing portion of the vacuum heat insulating material shown in FIG. 13A. It is an expanded sectional view. FIG. 13B is a schematic plan view of the vacuum heat insulating material shown in FIG. 13A. It is typical sectional drawing which shows an example of the non-return valve as an expansion relaxation part with which the vacuum heat insulating material shown to FIG. 13A and FIG. 14 is provided. It is typical sectional drawing which shows the other example of the non-return valve as an expansion relaxation part with which the vacuum heat insulating material shown to FIG. 13A and FIG. 14 is provided. It is a schematic diagram which shows an example of an intensity | strength fall part as an expansion relaxation part with which the vacuum heat insulating material shown to FIG. 13A and FIG. 14 is provided. 18A and 18B are schematic cross-sectional views each showing an example of a vacuum heat insulating material panel used in the heat insulating container according to Embodiment 7 of the present invention. 19A and 19B are schematic cross-sectional views respectively showing other examples of the vacuum heat insulating material panel shown in FIG. 18B. It is typical sectional drawing which shows the typical structure of the ground type LNG tank which is a heat insulation container which concerns on Embodiment 8 of this invention. It is typical sectional drawing which shows the typical structure of an underground LNG tank which is a heat insulation container which concerns on Embodiment 8 of this invention. It is typical sectional drawing which shows the typical structure of the hydrogen tank which is a heat insulation container which concerns on Embodiment 9 of this invention. It is one Example of this invention, Comprising: It is a graph which shows the result of the thermal simulation of the heat insulation container which concerns on this invention.

  The heat insulating container according to the present invention is used to hold a low-temperature substance stored at a temperature lower than normal temperature, and includes a container housing and a heat insulating structure disposed outside the container housing. The heat insulating structure is a multilayer structure including a first heat insulating layer, a second heat insulating layer, and a third heat insulating layer, which are sequentially provided from the container housing toward the outside, and the third heat insulating layer includes a plurality of heat insulating structures. It is the structure provided with the vacuum heat insulating material.

  According to the above configuration, the inner heat insulating layer includes a two-layer structure of the first heat insulating layer and the second heat insulating layer, and the third heat insulating layer is formed outside the inner heat insulating layer by the vacuum heat insulating material having excellent heat insulating performance. Has been. Thereby, the heat transfer (heat transfer) of the cold temperature (low heat) from the inside of the container housing is not only hindered by the two-layer structure of the first heat insulating layer and the second heat insulating layer, but further includes a vacuum heat insulating material. Obstructed by a thermal barrier. Therefore, it is possible to effectively suppress the leakage of the cold temperature to the outside. Furthermore, heat transfer from the outside air to the inside of the heat insulating structure is also hindered by the third heat insulating layer, so that it is also possible to effectively suppress an increase in the ambient temperature in the region where the inner heat insulating layer exists, and the heat insulating performance of the inner heat insulating layer is relatively controlled. Can be improved. As a result, the heat insulating performance of the heat insulating structure can be made excellent by the synergistic effect of the excellent heat insulating performance of the vacuum heat insulating material itself and the relatively improved heat insulating performance of the inner heat insulating layer.

  Moreover, the fact that the heat insulation performance of the inner heat insulating layer is relatively improved can reduce the influence of the cold temperature from the container housing on the third heat insulating layer by the inner heat insulating layer. Thereby, since the deterioration etc. of the vacuum heat insulating material which comprises a 3rd heat insulation layer can be suppressed, it also becomes possible to hold | maintain the heat insulation performance of a heat insulation structure favorably over a period.

  In the heat insulating container having the above configuration, the second heat insulating layer may have a heat insulating performance equal to or higher than that of the first heat insulating layer.

  According to the above configuration, the second heat insulating layer can effectively suppress leakage to the cold third heat insulating layer, and the second heat insulating layer insulates the inner first heat insulating layer, thereby insulating the first heat insulating layer. Can be improved relatively. Therefore, the heat insulating performance of the heat insulating structure can be further improved.

  Moreover, in the heat insulation container of the said structure, the structure in which the site | part with which the said 1st heat insulation layer and the said 2nd heat insulation layer were integrated may be contained in the said heat insulation structure.

  According to the said structure, a part of inner side heat insulation layer may be a single layer structure, and a part may be a 2 layer structure. Therefore, for example, one heat insulation panel is arranged outside the container housing, the heat insulation panel main body is integrated into a single layer, and the joint portion between the heat insulation panels is a two-layered structure including a first heat insulation layer and a second heat insulation layer. Can be structured. In general, the cold temperature is likely to leak at the joint between the heat insulation panels, but leakage from the joint can be effectively suppressed by partially improving the heat insulation performance by forming a two-layer joint. Thereby, the heat insulation performance of a heat insulation structure can be made more excellent.

  Further, in the heat insulating container having the above configuration, the vacuum heat insulating material includes a fibrous core material and a bag-shaped outer packaging material having gas barrier properties, and the core material is sealed in a vacuum state inside the outer packaging material. Among the outer packaging materials, the inner outer packaging material constituting the inner surface facing the container housing is configured to have higher low temperature resistance than the outer outer packaging material constituting the outer surface. Also good.

  According to the said structure, in a vacuum heat insulating material, the low temperature tolerance of the inner surface facing the container housing | casing which hold | maintains a low temperature substance will be improved. It can suppress well that the inner surface of a vacuum heat insulating material embrittles by low temperature. Thereby, the reliability of a heat insulation structure can be improved.

  Moreover, in the heat insulation container of the said structure, the said vacuum heat insulating material has the fin-shaped sealing part which bonded and sealed the said outer packaging materials around the circumference | surroundings, and the said sealing part is on the said container housing | casing side. The third heat insulating layer may be configured by disposing the vacuum heat insulating material outside the second heat insulating layer in a folded state.

  According to the said structure, since a fin-shaped sealing part is inserted | pinched between a 3rd heat insulation layer and a 2nd heat insulation layer, the leak of the cold temperature produced via a sealing part is suppressed effectively by these heat insulation layers. can do. Thereby, the heat insulation performance of a heat insulation structure can be made more excellent.

  Moreover, in the heat insulation container of the said structure, the structure arrange | positioned adjacently in the state which faced each other may be sufficient as the said several heat insulating material with which a said 3rd heat insulation layer is provided.

  According to the said structure, the 3rd heat insulation layer is formed by abutting the end surfaces of the edge part of a vacuum heat insulating material. Therefore, it is possible to prevent the cold temperature from leaking from the joint of the third heat insulating layer, so that the heat insulating performance of the third heat insulating layer can be improved and the heat insulating performance of the inner heat insulating layer can be relatively improved by the third heat insulating layer. It can be made even better. Thereby, the heat insulation performance of a heat insulation structure can be made more excellent.

  In the heat insulating container having the above-described configuration, a portion of the third heat insulating layer where the end surfaces of the vacuum heat insulating material are abutted with each other is filled with a filling heat insulating material different from the vacuum heat insulating material. May be.

  According to the said structure, a filling heat insulating material is provided in the joint of a 3rd heat insulation layer. Therefore, it is possible to further suppress the cold temperature from leaking from the joint of the third heat insulating layer. Thereby, the heat insulation performance of a heat insulation structure can be made more excellent.

  Moreover, in the heat insulation container of the said structure, said 1st heat insulation layer and said 2nd heat insulation layer are provided with several heat insulation panel, and the said heat insulation panel is arrange | positioned adjacent in the state which faced each other. Furthermore, when the part where the end faces of the heat insulating panel are abutted or the part where the end faces of the vacuum heat insulating material are abutted is the abutting part, the first heat insulating layer, the second heat insulating layer, and the first The structure which the position of the butting | matching site | part of the at least 2 heat insulation layer among the three heat insulation layers has become a position mutually shifted | deviated may be sufficient.

  According to the above configuration, for example, the seam of the second heat insulating layer is covered with the vacuum heat insulating material forming the third heat insulating layer, and the seam of the first heat insulating layer is covered with the heat insulating panel forming the second heat insulating layer. It will be. Therefore, it is possible to effectively suppress the cold temperature in the container casing from transferring heat to the outside air by transmitting the seams of the respective heat insulating layers. Thereby, the heat insulation performance of a heat insulation structure can be made more excellent. Here, the displacement of the position of the abutting portion means a displacement on the projection view when the projection view is assumed from the inside to the outside.

  Further, in the heat insulating container having the above configuration, the vacuum heat insulating material may be formed by the first heat insulating layer or the second heat insulating material in a state where the entire inner surface facing the container housing is not bonded to the outer surface of the second heat insulating layer. The structure may be mechanically fixed to the layer.

  According to the above configuration, even if the heat shrinkage behavior or the heat shrinkage rate is different between the vacuum heat insulating material and the inner heat insulating layer, the entire vacuum heat insulating material is warped and deformed, or the inner surface is repeatedly pulled and stretched. The possibility that cracks or the like occur in the outer packaging material can be effectively suppressed. Thereby, it becomes possible to hold | maintain the heat insulation performance of a heat insulation structure favorably over a period.

  Moreover, in the heat insulation container of the said structure, the structure arrange | positioned so that the distance from the said container housing | casing may become equal may be sufficient as the said adjacent vacuum heat insulating material.

  According to the said structure, the variation in the temperature distribution in the inner surface of a vacuum heat insulating material can be made small. Therefore, variation in the heat shrinkage of the vacuum heat insulating material due to uneven temperature distribution can be suppressed. As a result, it becomes possible to effectively suppress embrittlement or breakage of the outer packaging material of the vacuum heat insulating material, so that the heat insulating performance of the heat insulating structure can be well maintained over a period of time.

  Further, in the heat insulating container having the above configuration, the vacuum heat insulating material includes a fibrous core material and a bag-shaped outer packaging material having gas barrier properties, and the core material is sealed in a vacuum state inside the outer packaging material. And a structure having an explosion-proof structure that suppresses or prevents rapid deformation of the vacuum heat insulating material.

  According to the above configuration, since the vacuum heat insulating material has an explosion-proof structure, even if the vacuum heat insulating material located outside is exposed to a harsh environment and the residual gas inside expands, the vacuum heat insulating material rapidly Deformation can be effectively avoided. Therefore, since the excellent explosion-proof property can be exhibited, the stability of the vacuum heat insulating material can be further improved.

  Further, in the heat insulating container having the above-described configuration, the vacuum heat insulating material is configured as a heat insulating panel in which the outer packaging material is completely covered with a foamed resin layer, and the explosion-proof structure includes the foamed resin layer after foaming. The structure implement | achieved by forming so that an organic type foaming agent may not remain may be sufficient.

  Further, in the heat insulating container having the above-described configuration, the vacuum heat insulating material is further enclosed with the core material inside the outer packaging material and further includes an adsorbent that adsorbs residual gas therein, and the explosion-proof structure includes the adsorbent. Is a chemical adsorption type that chemically adsorbs the residual gas, non-exothermic that does not generate heat due to adsorption of the residual gas, or a configuration that is realized by being a chemical adsorption type and non-exothermic. May be.

  Further, in the heat insulating container having the above-described configuration, the explosion-proof structure is configured such that when the residual gas expands inside the outer packaging material, the expansion-relaxation portion releases the residual gas to the outside and relaxes the expansion. It may be a configuration realized by providing.

  Moreover, in the heat insulation container of the said structure, even if the said expansion | swelling mitigation part is a structure which is a site | part which is previously provided in the check valve provided in the said outer packaging material, or is provided in the said outer packaging material partially, and is low in intensity | strength. Good.

  Further, in the heat insulating container having the above-mentioned configuration, the outer packaging material has an opening for decompressing the inside of the bag, and the opening has an inner surface as a heat-welded layer, and the heat-welded layers are connected to each other. The inside of the bag can be sealed by heat welding in a contact state, and the sealing portion formed by heat welding of the opening has a thin portion where the thickness of the welding portion between the heat welding layers is small May be included.

  Moreover, in the heat insulation container of the said structure, the said outer packaging material is comprised from two lamination sheets, the one surface of the said lamination sheet is the said heat welding layer, and the said heat welding layers of the said lamination sheet are opposed to each other In a state in which two sheets are arranged, a part of the peripheral edge of the laminated sheet is used as the opening, and heat sealing is performed so as to surround the remaining part of the peripheral edge excluding the opening, thereby forming a bag shape. And the structure by which the site | part thermally welded in the said peripheral part becomes the said sealing part containing two or more said thin parts may be sufficient.

  Further, in the heat insulating container having the above-described configuration, the sealing portion includes a plurality of thick portions having a large thickness of the welding portion in addition to the plurality of thin portions, and the thick portion and the thin portion are: The thin-walled portion may be arranged alternately so that the thin-walled portion is positioned between the thick-walled portions.

  Moreover, in the heat insulation container of the said structure, the structure in which the said container housing | casing has a shape containing a curved surface may be sufficient.

  According to the said structure, the vacuum heat insulating material arrange | positioned adjacent to a curved surface becomes easy to equalize the distance from a container housing | casing. Thereby, variation in thermal contraction of the vacuum heat insulating material is suppressed and the reliability of the vacuum heat insulating material is improved, so that the heat insulating performance of the heat insulating structure can be favorably maintained over a period.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In the following description, the same or corresponding elements are denoted by the same reference symbols throughout the drawings, and redundant description thereof is omitted.

(Embodiment 1)
A typical example of the heat insulating container according to the present invention will be specifically described with reference to FIGS. 1A, 1B, and 2 to 4.

[Insulated container]
In the first embodiment, as a typical example of the heat insulating container according to the present invention, an LNG spherical tank 101 provided in the LNG transport tanker 100 will be described as shown in FIG. 1A. As shown in FIG. 1A, the LNG transport tanker 100 according to the present embodiment is a tank independent tank type tanker, and includes a plurality of spherical tanks 101 (five in FIG. 1A). The plurality of spherical tanks 101 are arranged in a line along the longitudinal direction of the hull 102. As shown in FIG. 1B, each spherical tank 101 includes a heat insulating container 104, and the inside of the heat insulating container 104 is an internal space (fluid holding space) for storing (holding) liquefied natural gas (LNG). Yes. Further, most of the spherical tank 101 is externally supported by the hull 102, and the upper part thereof is covered by the cover 103.

  As shown in FIG. 1B, the heat insulating container 104 includes a container housing 110 and a heat insulating structure 105 that insulates the outer surface of the container housing 110. The container housing 110 is configured to hold a low-temperature substance stored at a temperature lower than normal temperature, such as LNG, and is made of a metal such as a stainless steel material or an aluminum alloy. Since the temperature of LNG is normally −162 ° C., a specific container housing 110 may be an aluminum alloy having a thickness of about 50 mm. Alternatively, it may be made of stainless steel having a thickness of about 5 mm.

  The heat insulating container 104 is fixed to the hull 102 by a support 106. The support 106 is generally called a skirt and has a thermal brake structure. The thermal brake structure is a structure in which, for example, stainless steel having a low thermal conductivity is inserted between an aluminum alloy and a low-temperature steel material, so that intrusion heat can be reduced.

  The heat insulation structure 105 is a multilayer structure of a heat insulation layer disposed on the outside of the container housing 110. For example, as shown in FIG. 2, the first heat insulation is provided in order from the container housing 110 toward the outside. The multilayer structure includes the layer 111, the second heat insulating layer 112, and the third heat insulating layer 113. In the present embodiment, as shown in FIG. 2, the heat insulating structure 105 includes a portion where the first heat insulating layer 111 and the second heat insulating layer 112 exist independently, and the first heat insulating layer 111 and the second heat insulating layer 111. There is a portion where the heat insulating layer 112 is integrated. A portion where the first heat insulating layer 111 and the second heat insulating layer 112 are integrated is referred to as an “integrated layer 33” for convenience.

  In the present embodiment, the first heat insulating layer 111, the second heat insulating layer 112, and the integrated layer 33 are collectively configured as a heat insulating panel 30A. The heat insulating panel 30A is made of a foamed resin heat insulating material such as styrene foam (polystyrene foam), polyurethane foam, or phenol foam, or an inorganic heat insulating material such as glass wool or pearlite filled in a heat insulating frame. Of course, you may comprise with well-known heat insulation materials other than these. Since these heat insulating materials are foams except glass wool, the heat insulating panel 30A is referred to as “foam heat insulating panel 30A” for convenience of explanation.

  On the outside of the container housing 110, a rectangular foam heat insulation panel 30A is arranged and fixed in units of several thousand sheets. The thickness of the foam heat insulation panel 30A is not particularly limited. In the present embodiment, the foam heat insulation panel 30A is made of bead method expanded polystyrene (EPS), and in this case, the thickness may be in the range of 300 mm to 400 mm. On the outside of the foam heat insulating panel 30A, a square vacuum heat insulating material 20A is arranged in units of several thousand sheets, whereby a third heat insulating layer 113 is formed.

  Most of the foam heat insulation panel 30A is an integrated layer 33 in which the first heat insulation layer 111 and the second heat insulation layer 112 are integrated, but the first heat insulation layer is provided on the outer periphery of the foam heat insulation panel 30A. The edge part 31 which consists only of 111, and the edge part 32 which consists only of the 2nd heat insulation layer 112 are included. When viewed as the shape of the foam heat insulation panel 30A, the integrated layer 33 is the main body, and the protrusions (the edge 31 and the edge 32) projecting outward with a half thickness of the main body around the main body. In this protrusion, a step is formed on the outer surface of the foam heat insulation panel 30A, and the inner surface (surface facing the container housing 110) is flat on the inner protrusion, that is, the edge 31 and the foam. A step is formed on the inner side surface of the heat insulating panel 30 </ b> A, and an outer protrusion or edge 32 having a flat outer surface is included.

  When the foam heat insulating panels 30 </ b> A are arranged adjacent to each other, as shown in FIG. 2, an edge portion 31 (inner protruding portion) made of only the first heat insulating layer 111 and an edge portion 32 made of only the second heat insulating layer 112. After matching (outside protrusion), the respective steps (first heat insulating layer 111 and second heat insulating layer 112) are overlapped. Thereby, foam insulation panel 30A can be stably arranged adjacently.

  Therefore, in the present embodiment, an inner heat insulating layer made of the foam heat insulating panel 30A is formed outside the container housing 110, and an outer heat insulating layer (third heat insulating layer 113) made of the vacuum heat insulating material 20A is further formed outside thereof. The inner heat insulating layer includes a portion made of the integrated layer 33 and a portion made of the first heat insulating layer 111 and the second heat insulating layer 112.

  As described above, the third heat insulating layer 113 using the vacuum heat insulating material 20 </ b> A is provided outside the second heat insulating layer 112 or the integrated layer 33. The vacuum heat insulating materials 20 </ b> A are adjacently arranged so that the end surfaces of the edge portions are abutted with each other. As will be described later, the outer periphery of the vacuum heat insulating material 20A is formed as a fin-like sealing portion 24 (or sealing fin), and this sealing portion 24 is arranged so as to be folded inward on the lower temperature side. Has been. Therefore, the sealing part 24 is located between the main body of the vacuum heat insulating material 20A and the foam heat insulating panel 30A.

  Moreover, 20 A of vacuum heat insulating materials may be integrated with the outer surface of the foam heat insulation panel 30A, and may be piled up on the outer side of the foam heat insulation panel 30A without being integrated. Further, as shown in FIG. 2, the butt portion between the vacuum heat insulating materials 20A, that is, the joint position of the third heat insulating layer 113 is located outside the butt portion between the foam heat insulating panels 30A, ie, the second heat insulating layer 112. The positions of the seams may substantially coincide with each other, and the positions of the seams of the respective heat insulating layers may be shifted as exemplified in the second embodiment described later.

  In the present embodiment, filled heat insulating materials 14 and 15 are filled in the butted portion between the foam heat insulating panels 30A and the butted portion between the vacuum heat insulating materials 20A. Filling heat insulating materials 14 and 15 are filled in gaps between the butted portions in order to ensure heat insulation between the butted portions of the foam heat insulating panel 30A and the vacuum heat insulating material 20A. In the present embodiment, micro glass wool having a fiber diameter of less than 1 μm is used as the filling heat insulating materials 14 and 15, but is not limited thereto, has heat insulating properties, and is flexible and rich in elasticity. Any material can be used. Specifically, for example, soft urethane, phenol foam containing a reinforcing component, polyurethane foam containing a reinforcing component, and the like can be given. If it is a resin foam containing a reinforcing component, an expansion behavior close to the linear expansion coefficient of the container housing 110 can be realized.

  In addition, as shown in FIG. 2, the filling heat insulating material 15 provided in the butt | matching site | part of 20 A of vacuum heat insulating materials is the filling heat insulating material 30A filled in the butt | matching site | part of 30 A of foam heat insulation panels or foam insulation panel 30A In order not to contact 14, a gap may be provided for filling. Thereby, since heat transfer from the foam heat insulating panel 30A or the filled heat insulating material 14 to the filled heat insulating material 15 can be suppressed, the cold temperature from the inner heat insulating layer is reduced from leaking between the vacuum heat insulating materials 20A. be able to.

  On the contrary, since it is possible to suppress the heat of the outside air from being transferred between the vacuum heat insulating materials 20A, a space (foam heat insulating panel 30A) formed between the vacuum heat insulating material 20A and the container housing 110 is also possible. It is possible to improve the heat insulation state of the space). Therefore, the heat insulating performance of the foam heat insulating panel 30A can be relatively improved.

  Further, as described above, a flexible and stretchable material is used as the filling heat insulating material 15. Thereby, even if the vacuum heat insulating material 20A expands and contracts according to the temperature change of the outside air, and the gap between the vacuum heat insulating materials 20A changes, the filled heat insulating material 15 can also expand and contract accordingly. Thereby, it is substantially avoided that the filling heat insulating material 15 restrains expansion and contraction of the vacuum heat insulating material 20 </ b> A, and crack damage and the like of the outer packaging material 22 can be effectively suppressed.

  The structure which attaches the heat insulation structure 105 to the container housing | casing 110 is not specifically limited, A well-known method can be used suitably. In this Embodiment, as shown in FIG. 2, the heat insulation structure 105 is being fixed with the fastening member 13 comprised from the volt | bolt 13a and the nut 13b. Specifically, a nut 13b is bonded and fixed to the container housing 110 by a technique such as welding, and a bolt 13a is inserted into the nut 13b so as to penetrate from the outside of the third heat insulating layer 113 (vacuum heat insulating material 20A). Inserted and screwed together. At this time, since the vacuum heat insulating material 20A is provided with a through hole whose periphery is sealed, the inside of the vacuum heat insulating material 20A is maintained in a vacuum state.

  At this time, the site | part which fastens the vacuum heat insulating material 20A is not specifically limited, For example, the said through-hole should just be provided in the center part of the square vacuum heat insulating material 20A, and the volt | bolt 13a may be inserted in this through-hole. As the fastening member 13, a known member other than the bolt 13a and the nut 13b can be used.

  Furthermore, the bolt 13a of the fastening member 13 is screwed into the nut 13b of the container housing 110 in a state of penetrating not only the foam heat insulating panel 30A but also the vacuum heat insulating material 20A. Therefore, the vacuum heat insulating material 20A can be disposed outside the foam heat insulating panel 30A without bonding the entire inner side surface to the outer side surface of the foam heat insulating panel 30A with an adhesive or the like. In this state, the vacuum heat insulating material 20A is free from expansion and contraction due to heat of the foam heat insulating panel 30A.

  20 A of vacuum heat insulating materials are provided in the outer side of the foam heat insulation panel 30A which is an inner side heat insulation layer, and are the outer side heat insulation layers which touch external air in this Embodiment. On the other hand, the foam heat insulation panel 30 </ b> A constitutes the first heat insulation layer 111 and the second heat insulation layer 112 (and the integrated layer 33), and thus is easily cooled by the cold temperature from the container housing 110. Therefore, a difference is likely to occur between the heat shrinkage behavior of the vacuum heat insulating material 20A and the heat shrinkage behavior of the foam heat insulating panel 30A.

  On the other hand, in the present embodiment, the vacuum heat insulating material 20A has a foam heat insulating panel 30A (first surface) in a state where the entire inner surface is not bonded to the outer surface of the foam heat insulating panel 30A (second heat insulating layer 112). It is mechanically fixed to the heat insulation layer 111 or the second heat insulation layer 112). Therefore, even if the heat shrinkage behavior or the heat shrinkage rate differs between the vacuum heat insulating material 20A and the foam heat insulating panel 30A (the second heat insulating layer 112 or the integrated layer 33), the entire vacuum heat insulating material 20A It is possible to effectively suppress the possibility of warping deformation or cracking or the like in the outer packaging material (described later) on the inner surface due to repeated stretching and stretching.

  Thereby, a possibility that a gap may be generated between the third heat insulating layer 113 and the second heat insulating layer 112 or the integrated layer 33, or the heat insulating performance of the vacuum heat insulating material 20A itself may be effectively suppressed. Therefore, it is possible to avoid a decrease in the heat insulating performance of the heat insulating structure 105, and it is possible to maintain the effectiveness of the heat insulating performance over a long period of time. Therefore, the reliability of the heat insulating structure 105 can be improved.

  The vacuum heat insulating material 20A only needs to be mechanically fixed to at least the container housing 110 by the fastening member 13 or the like. However, the vacuum heat insulating material 20A is partially partially outside the foam heat insulating panel 30A (second heat insulating layer 112 or It may be adhesively fixed to the integrated layer 33). For example, a configuration in which the central portion of the square vacuum heat insulating material 20A is bonded to a pin point with a known adhesive and an appropriate portion of the outer peripheral portion is fastened with the fastening member 13 can be exemplified, but there is no particular limitation.

  In the present embodiment, the third heat insulating layer 113 formed using the vacuum heat insulating material 20A is the first heat insulating layer 111 and the second heat insulating layer 112 (and integrated) formed using the foam heat insulating panel 30A. It covers almost the entire surface of the layer 33). The almost entire surface here means 85% or more, preferably 90% or more, more preferably 95% or more of the outer surface of the second heat insulating layer 112 and the integrated layer 33 (that is, the outer surface of the foam heat insulating panel 30A), Particularly preferably, it means 98% or more.

  The heat insulating property of the vacuum heat insulating material 20A constituting the third heat insulating layer 113 is a foam heat insulating material that forms the first heat insulating layer 111 and the second heat insulating layer 112 (and the integrated layer 33 in which they are integrated). It is lower than the panel 30A. For example, since the vacuum heat insulating material 20A used in the present embodiment has a thermal conductivity λ = 0.002 W / m · K (at 0 ° C.), the foamed polystyrene (foamed foam) which is the material of the foam heat insulating panel 30A About 15 times lower than polystyrene). Therefore, in the present embodiment, the third heat insulating layer 113 (outer heat insulating layer) has a lower thermal conductivity than the second heat insulating layer 112 (inner heat insulating layer), and is outside the second heat insulating layer 112. It covers almost the entire surface.

  Thereby, the heat transfer from the inside of the container housing 110 toward the outside can be greatly reduced, and the high heat insulating performance of the vacuum heat insulating material 20A that is the third heat insulating layer 113 can be effectively exhibited. . Further, the third heat insulating layer 113 can effectively suppress the penetration of outside air heat into the inside. Therefore, the temperature between the third heat insulating layer 113 and the container housing 110, that is, the temperature of the portion where the first heat insulating layer 111 and the second heat insulating layer 112 are installed can be significantly reduced.

  Therefore, according to the configuration of the present embodiment, the high heat insulating performance of the vacuum heat insulating material 20A constituting the third heat insulating layer 113 and the heat insulating performance of the first heat insulating layer 111, the second heat insulating layer 112, and the integrated layer 33 Due to this synergistic effect, the heat insulating performance of the heat insulating structure 105 can be made extremely high. Furthermore, the third heat insulating layer 113 is configured by arranging the vacuum heat insulating material 20A side by side on the outer side of the second heat insulating layer 112 or the integrated layer 33, and it is not necessary to overlap the vacuum heat insulating material 20A. It is possible to reduce the usage amount of the expensive vacuum heat insulating material 20A.

[Vacuum insulation]
Next, an example of a specific configuration of the vacuum heat insulating material 20A used in the present embodiment will be specifically described. As shown in FIG. 3, the vacuum heat insulating material 20 </ b> A includes a core material 21, an outer packaging material (covering material) 22, and an adsorbent 23. The core material 21 and the adsorbent 23 are sealed inside the outer packaging material 22 in a reduced-pressure sealed state (substantially vacuum state). The outer packaging material 22 is a bag-shaped member having a gas barrier property. In the present embodiment, the two laminated sheets 220 are opposed to each other and the periphery thereof is sealed by the sealing portion 24 to form a bag shape. Yes. Moreover, since the core material 21 does not exist inside and the laminated sheets 220 are in contact with each other, the sealing portion 24 is formed in a fin shape extending from the main body of the vacuum heat insulating material 20A toward the outer periphery.

  The core material 21 is a fibrous member. In the present embodiment, for example, a glass fiber produced by a centrifugation method having an average fiber diameter of 4 μm is used. By using inorganic fibers such as glass fibers as the core material 21, flame retardancy can be improved as compared with the case of using organic fibers. The glass fiber may not be fired, but the fired glass fiber can improve the stability of the vacuum heat insulating material 20A.

  Since the inner side surface of the vacuum heat insulating material 20A may be exposed to a low temperature that is 100 ° C. or more lower than normal temperature, the outer packaging material 22 on the inner side surface may be embrittled due to low temperature. On the other hand, by using the baked glass fiber, the degree of dimensional change of the core material 21 can be effectively suppressed even if the bag breakage due to the embrittlement of the outer packaging material 22 occurs.

  When the pressure inside the outer packaging material 22 is reduced, dimensional deformation occurs in the core material 21. If the glass fiber is not fired, its dimensional deformation is twice or more (generally about 5 to 6 times), so the outer packaging material 22 breaks and the core material 21 undergoes dimensional deformation. Sometimes, the thickness of the vacuum heat insulating material 20A increases. On the other hand, when the baked glass fiber is used, the dimensional deformation can be suppressed to about 1.2 times, and at most 1.5 times or less. Therefore, even if the core material 21 undergoes dimensional deformation, the influence on the vacuum heat insulating material 20A can be suppressed.

  In this embodiment, the glass fiber manufactured by the centrifugal method is used as the core material 21, but the method of manufacturing the glass fiber is not limited to the centrifugal method, and a known manufacturing method such as a papermaking method (previously water It is also possible to employ a method in which the glass fiber dispersed in is formed into a paper and dehydrated. For example, since the manufacturing method itself called a papermaking method is a method for reducing the thickness of the glass fiber, even if the glass fiber produced by the papermaking method is used as the core material 21, the dimensional deformation tends to be small. Therefore, even if the outer packaging material 22 is broken, it is possible to suppress the influence caused by the dimensional deformation of the core material 21.

  In the present embodiment, the laminated sheet 220 has a configuration in which three layers of a surface protective layer 221, a gas barrier layer 222, and a heat welding layer 223 are laminated in this order. Specifically, for example, the surface protective layer 221 includes a nylon film having a thickness of 35 μm, the gas barrier layer 222 includes an aluminum foil having a thickness of 7 μm, and the heat welding layer 223 includes a thickness of 50 μm. And a low density polyethylene film.

  The adsorbent 23 penetrates slightly from the residual gas (including water vapor) released from the fine voids of the core material 21 after the core material 21 is sealed under reduced pressure inside the outer packaging material 22, the sealing portion 24, and the like. The outside air (including water vapor) is absorbed and removed. The adsorbent 23 is sealed in a known container. This container is sealed in a sealed state under reduced pressure together with the core material 21 inside the outer packaging material 22, and then, for example, a hole is opened by an external force. Thereby, the adsorption performance of the adsorbent 23 can be exhibited.

  Note that more specific configurations of the core material 21, the outer packaging material 22, and the adsorbent 23 will be described in detail in a later-described embodiment 6 (vacuum heat insulating material 20C having an explosion-proof structure).

  Moreover, in this Embodiment, you may form the flame-resistant layer 225 in the whole surface (both an outer surface and an inner surface) of the main body (part other than the fin-shaped sealing part 24) of the vacuum heat insulating material 20A. Then, the sealing portion protective layer 27 may be formed on the outer peripheral portion of the sealing portion 24.

  As shown in FIG. 3, the flame retardant layer 225 is formed on the surface of the outer packaging material 22 (outside the surface protective layer 221), and in this embodiment, a commercially available aluminum tape (for example, a thickness of 50 μm) is used. . By sticking this aluminum tape so as to cover the main body of the vacuum heat insulating material 20A, flame resistance can be imparted to the vacuum heat insulating material 20A. In addition, since the aluminum tape has conductivity, even if some current due to electric leakage or the like is transmitted to the vacuum heat insulating material 20A, the current can be released. Thereby, the possibility that an electric current passes through the inside of the vacuum heat insulating material 20A is reduced, and the inside of the vacuum heat insulating material 20A can be substantially electrically shielded (giving electrical shielding properties).

In addition to the aluminum tape, the flame retardant layer 225 may be a sheet (aluminum sheet), a plate (aluminum plate), or the like. In addition, the term “aluminum” as used herein includes not only aluminum alone but also an aluminum alloy. Further, instead of aluminum, other metals (for example, copper, stainless steel, titanium, etc.) or alloys thereof may be used. The flame retardant layer 225 only needs to have flame retardancy and conductivity, but it is desirable that the flame retardant layer 225 has good durability from the viewpoint of imparting good flame retardancy to the vacuum heat insulating material 20A. In addition, about a flame retardance, what is necessary is just more than UL510FR which is a flame retardance specification of US Insurer Safety Laboratory (UL: Underwriters Laboratories).

  The sealing part protective layer 27 may be a flame-retardant layer configured to cover the outer peripheral part of the fin-like sealing part 24, that is, the part where the cross section of the laminated sheet 220 is exposed. In this embodiment, the sealing portion protective layer 27 is configured by attaching a tape made of vinyl chloride to the sealing portion 24, but is not limited thereto, and is formed of a known flame-retardant material. A tape-like or sheet-like material or a known sealing material (sealer) having flame retardancy can be used. Like the flame retardant layer 225, the flame retardant required for the sealing part protective layer 27 may be UL510FR-compliant or higher. Moreover, it is preferable that the sealing part protective layer 27 has electrical insulation in addition to flame retardancy. By providing the sealing part protective layer 27, the flame retardancy and electrical shielding properties of the vacuum heat insulating material 20A can be improved.

  In the present embodiment, the formation of the flame retardant layer 225 and the sealing portion protective layer 27 is not essential. However, if the heat insulating container 104 according to the present embodiment is used for the spherical tank 101 of the LNG transport tanker 100, the vacuum heat insulating material 20A may have good flame retardancy and electrical shielding properties. preferable. Therefore, by providing either one or both of the flame retardant layer 225 and the sealing portion protective layer 27, the reliability and durability of the vacuum heat insulating material 20A can be improved.

[Thermal insulation by thermal insulation structure]
Next, the heat insulating action by the heat insulating structure 105 having the above-described configuration will be specifically described. As described above, the heat insulating container 104 according to the present embodiment includes the heat insulating structure 105 provided on the outer side of the container housing 110, and the heat insulating structure 105 includes the first heat insulating layer 111 and the inner heat insulating layer. The multilayer structure includes the second heat insulating layer 112, the integrated layer 33, and the third heat insulating layer 113 provided outside the second heat insulating layer 112. A low-temperature substance such as LNG is held inside the container housing 110.

  Here, the first heat insulating layer 111, the second heat insulating layer 112, and the integrated layer 33 located on the container housing 110 side are almost entirely covered with the third heat insulating layer 113. The heat insulating layer 113 is composed of a vacuum heat insulating material 20A having excellent heat insulating performance. That is, the heat of the vacuum heat insulating material 20A constituting the third heat insulating layer 113 is higher than that of the polystyrene foam constituting the first heat insulating layer 111, the second heat insulating layer 112, and the integrated layer 33 (inner heat insulating layer). The conductivity λ is greatly reduced. Therefore, even if the cold temperature of the container housing 110 is transferred to the outside (heat transfer) via the first heat insulating layer 111, the second heat insulating layer 112, or the integrated layer 33, the vacuum of the third heat insulating layer 113 is maintained. It becomes possible to prevent effectively by the heat insulating material 20A, and the leak to the cold outside air can be greatly reduced.

  Moreover, when viewed from the inner heat insulating layer, the outer surface of the inner heat insulating layer is almost entirely covered with the vacuum heat insulating material 20A. Therefore, the excellent heat insulating performance of the vacuum heat insulating material 20A can be expected to have an effect of substantially blocking heat transfer from the outside air to the inner heat insulating layer. Thereby, since the possibility that the atmospheric temperature in the region where the inner heat insulating layer exists (inner heat insulating region) can be effectively suppressed due to outside air, the heat insulating performance of the inner heat insulating layer can be relatively improved. As a result, the heat insulating performance of the heat insulating structure 105 can be made extremely excellent by the synergistic effect of the excellent heat insulating performance of the vacuum heat insulating material 20A itself and the heat insulating performance relatively improved by the inner heat insulating layer.

  In particular, the inner heat insulating layer includes not only a single layer structure like the integrated layer 33 but also a portion having a two-layer structure in which the first heat insulating layer 111 and the second heat insulating layer 112 are overlapped. In this two-layer structure portion, an air layer is formed between the layers, and material continuity is broken. For example, in the present embodiment, the integrated layer 33 is a single continuous layer in the thickness direction as one foamed polystyrene layer, but the two-layer structure portion of the first heat insulating layer 111 and the second heat insulating layer 112. Then, there is no continuity between the first heat insulating layer 111 and the second heat insulating layer 112, and the first heat insulating layer 111 is disconnected. Thereby, since the inner heat insulating layer of the heat insulating structure 105 is at least partially multilayered, the heat insulating performance is improved by the three-layer structure including the third heat insulating layer 113 (vacuum heat insulating material 20A).

  Here, in the present embodiment, the portion of the two-layer structure corresponds to the abutting portion (the joint between the first heat insulating layer 111 and the second heat insulating layer 112 and the integrated layer 33) between the foam heat insulating panels 30A. In comparison with the main body of the heat insulation panel, the internal cold temperature is likely to leak from the abutting portion between the heat insulation panels. On the other hand, in this embodiment, since the joint portion has a two-layer structure, the vicinity of the seam of the second heat insulating layer 112 can be multi-layered, so that cold temperature leakage from the seam can be effectively reduced. .

  Moreover, in the present embodiment, the filling heat insulating material 14 is filled in the gaps (gap between the edge portions 31 and 32 of the foam heat insulation panel 30A) serving as joints. Moreover, in this Embodiment, although the foam heat insulation panel 30A and the vacuum heat insulating material 20A are integrated, the filling heat insulating material 15 is filled also between 20A of vacuum heat insulating materials. Thereby, it can further suppress that the cold temperature from the inside of the container housing | casing 110 leaks to external air through a joint. As a result, the heat insulation structure 105 as a whole can ensure good heat insulation performance while effectively utilizing the heat insulation performance of the vacuum heat insulating material 20A.

  Moreover, since the leak of the cold temperature from a joint can be reduced effectively, the 3rd heat insulation layer 113 avoids the need to overlap | superpose the vacuum heat insulating material 20A for every plurality. Therefore, the third heat insulating layer 113 can be substantially composed of a single layer of the vacuum heat insulating material 20A. Thereby, since it is possible to suppress an increase in the number of sheets of the relatively effective vacuum heat insulating material 20A used, it is possible to save resources when manufacturing the heat insulating container 104.

  Further, when viewed from the vacuum heat insulating material 20A, the amount of cold leak from the joint of the inner heat insulating layer (the two-layer structure of the first heat insulating layer 111 and the second heat insulating layer 112) is reduced. Therefore, embrittlement due to the low temperature of the outer packaging material 22 can be suppressed, and warpage deformation and the like of the vacuum heat insulating material 20A can also be suppressed. Thereby, it becomes possible to hold | maintain the heat insulation performance of 20 A of vacuum heat insulating materials over a long period of time.

  As described above, if the heat insulating performance of the heat insulating structure 105 can be improved, the inner heat insulating layer can be particularly thinned. Therefore, if the overall size of the heat insulating container 104 does not change, the internal volume of the container housing 110 can be increased (see the example described later).

  In addition, in the LNG transport tanker 100 as shown in FIG. 1A, LNG boil-off gas is generally used as a fuel, but the insulated container 104 according to the present embodiment is used as a spherical tank 101 of such an LNG transport tanker 100. If it is used, generation | occurrence | production of boil-off gas can be suppressed by the outstanding heat insulation performance, and since the usage-amount as a fuel of boil-off gas can also be suppressed, economical efficiency can be improved. Further, even when the boil-off gas is reliquefied, the generation of the boil-off gas itself can be suppressed, so that the energy loss accompanying reliquefaction can be reduced.

  Furthermore, in the present embodiment, the first heat insulating layer 111, the second heat insulating layer 112, and the integrated layer 33 are configured as an integral foam heat insulating panel 30A. It arrange | positions so that the whole outer surface of the spherical container housing | casing 110 may be covered. In other words, since the vacuum heat insulating material 20A is disposed on the outer surface of the inner heat insulating layer, the distance from the low temperature material such as LNG to the vacuum heat insulating material 20A is substantially the same over the entire region. Therefore, the transmission of the cold temperature from the inside of the container housing 110, that is, the amount of the cold temperature leak is substantially equal over the entire inner heat insulating layer.

  Moreover, the butt portion (seam) where the cold temperature is likely to leak as compared to the main body (integrated layer 33) of the foam heat insulating panel 30A has a two-layer structure of the first heat insulating layer 111 and the second heat insulating layer 112. The difference in heat insulation performance between the main body and the seam can be reduced. As a result, the temperature distribution on the inner side surface of the vacuum heat insulating material 20A, that is, the surface where the inner heat insulating layer and the vacuum heat insulating material 20A are in contact with each other can be made more equal. Therefore, variation in temperature distribution on the inner side surface of the vacuum heat insulating material 20A can be reduced, and variation in thermal shrinkage of the outer packaging material 22 due to uneven temperature distribution is also suppressed. As a result, embrittlement or breakage due to a decrease in mechanical strength of the outer packaging material 22 can be further suppressed, and the heat insulating performance of the vacuum heat insulating material 20A can be maintained for a longer period of time.

  In addition, in the present embodiment, since the fin-shaped sealing portion 24 of the vacuum heat insulating material 20A is folded inward, the cold temperature leakage that occurs through the fin-shaped sealing portion 24 is effectively suppressed. You can also Further, an inorganic fiber such as glass fiber is used for the core material 21 of the vacuum heat insulating material 20A, a flame retardant layer 225 covering the main body of the vacuum heat insulating material 20A is provided, or a flame retardant seal is provided on the outer peripheral portion of the sealing portion 24. By providing the stop protection layer 27, the flame retardancy of the vacuum heat insulating material 20A can be improved. As a result, even if a fire occurs outside, it is possible to effectively suppress similar burning into the heat insulating container 104 due to the flame retardancy of the vacuum heat insulating material 20A.

  Moreover, in this Embodiment, the vacuum heat insulating material 20A is laminated | stacked and arrange | positioned, without being completely fixed with respect to the foam heat insulation panel 30A from which heat contraction behavior or a heat contraction rate differs. Thereby, the deformation | transformation of 20 A of vacuum heat insulating materials, or the failure | damage of the outer packaging material 22 of 20 A of vacuum heat insulating materials can be suppressed favorably. In particular, even if heat shrinkage occurs in the foam heat insulation panel 30A due to a change in the use environment of the heat insulation container 104, the possibility that the vacuum heat insulating material 20A is stretched or contracted due to the heat shrinkage is substantially prevented. Therefore, it is possible to avoid the possibility that the mechanical strength is reduced due to repeated tension expansion and contraction and the outer packaging material 22 is damaged such as a crack, and it is possible to maintain good heat insulation performance over a long period of time.

  In the present invention, the decrease in the mechanical strength of the outer packaging material 22 (and the laminated sheet 220 constituting the outer packaging material 22) is evaluated by measuring the tensile strength of the outer packaging material 22. Specifically, in accordance with JIS K 7124 and ISO 527-3, the sample to be measured (such as the outer packaging material 22 or the laminated sheet 220) is pulled by being exposed to a normal temperature or low temperature environment at a pulling speed of 100 mm / min. The strength is measured, and the evaluation is based on how much the tensile strength in a low-temperature environment decreases from the tensile strength in a normal-temperature environment. The low temperature environment can be realized by mixing ethanol, liquid nitrogen, and dry ice at -100 ° C, and can be realized by liquid nitrogen at -196 ° C.

  Furthermore, since the third heat insulating layer 113 composed of the vacuum heat insulating material 20A covers almost the entire surface of the foam heat insulating panel 30A, the surface temperature of the foam heat insulating panel 30A (the second heat insulating layer 112 or the integrated layer 33). It is also possible to suppress the variation in the temperature outside) due to environmental changes. Thereby, since heat contraction of the foam heat insulation panel 30A itself is suppressed, the difference in the heat shrinkage behavior between the vacuum heat insulating material 20A and the foam heat insulation panel 30A can be reduced.

  For example, in an environment where the heat insulating container 104 is exposed to sunlight, unevenness in heat distribution is likely to occur between the sunlit portion and the shaded portion of the heat insulating structure 105. The unevenness of heat distribution has a great influence on the heat shrinkage behavior of the entire foam heat insulation panel 30A, and may cause a partial difference in the heat shrinkage rate of the foam heat insulation panel 30A.

  On the other hand, in this Embodiment, since the foam heat insulation panel 30A is thermally insulated from external air by the vacuum heat insulating material 20A, the deformation | transformation etc. which originate in the temperature change of the foam heat insulation panel 30A can be suppressed effectively. . As a result, generation of a gap between the third heat insulating layer 113 and the second heat insulating layer 112 can be satisfactorily suppressed, and deformation or breakage of the vacuum heat insulating material 20A constituting the third heat insulating layer 113 can be suppressed. Can do. Thereby, the reliability of the heat insulation structure 105 can be improved.

[Modification]
In the heat insulating container 104 according to the present embodiment, the configuration shown in FIG. 2 is given as a representative example of the heat insulating structure 105, but the present invention is not limited to this. For example, in the configuration shown in FIG. 2, the fastening member 13 passes through the integrated layer 33 of the foam heat insulating panel 30 </ b> A to fix the foam heat insulating panel 30 </ b> A to the container housing 110. The fixing method by 13 is not limited to this. For example, as shown in FIG. 4, the fastening member 13 is penetrated through a portion where the first heat insulating layer 111 and the second heat insulating layer 112 are overlapped, thereby the first heat insulating layer 111 and the second heat insulating material together with the vacuum heat insulating material 20A. The layer 112 may be fastened together. The fastening location of the foam heat insulation panel 30A (and the vacuum heat insulating material 20A) by the fastening member 13 is not particularly limited, and may be fastened at a suitable location according to various conditions.

  Further, the vacuum heat insulating material 20A is not mechanically fastened by the fastening member 13, but may be bonded and fixed to the foam heat insulating panel 30A by a known adhesive 16, as shown in FIG. In this configuration, for example, the adhesive 16 is applied to a plurality of locations on the inner surface of the vacuum heat insulating material 20A, and is adhered and pasted to the outer surface of the foam heat insulating panel 30A. Examples of the adhesive 16 include known hot melt adhesives, but are not particularly limited. In addition, examples of the plurality of bonding locations include four corners and the vicinity of the center, but are not particularly limited.

  Furthermore, in this Embodiment, as shown in FIG.2, FIG4 and FIG.5, the position of the joint of the 3rd heat insulation layer 113 (butting part of 20 A of vacuum heat insulating materials) and the joint of the 2nd heat insulation layer 112 ( The position of the abutting portion between the foam heat insulating panels 30A substantially coincides. However, the present invention is not limited to this, and the position of the seam of the third heat insulation layer 113 and the position of the seam of the second heat insulation layer 112 are intentionally shifted as illustrated in the second embodiment to be described later. The vacuum heat insulating material 20A may be arranged.

(Embodiment 2)
In the first embodiment, the heat insulating structure 105 includes the first heat insulating layer 111 and the second heat insulating layer 112, and the portion where the first heat insulating layer 111 and the second heat insulating layer 112 are integrated (integrated layer 33). ), But in the second embodiment, the first heat insulating layer 111 and the second heat insulating layer 112 are completely independent layers and do not include the integrated layer 33. Yes. In the second embodiment, the heat insulating structure 105 having such a configuration will be described with reference to FIGS.

  Specifically, as shown in FIG. 6, the first heat insulating layer 111 is configured by arranging a large number of foam heat insulating panels 30 </ b> B on the outside of the container housing 110. The second heat insulating layer 112 is configured by arranging a large number of foam heat insulating panels 30B, and the third heat insulating layer 113 is formed by arranging a large number of vacuum heat insulating materials 20A outside the second heat insulating layer 112. It is configured. Further, as in the first embodiment, the filling heat insulating material 14 is provided between the joint of the first heat insulating layer 111 and the joint of the second heat insulating layer 112, that is, between the butted portions of the foam heat insulating panels 30B. Filled heat insulating material 15 is filled between the joints of the third heat insulating layer 113, that is, between the butted portions of the vacuum heat insulating materials 20A.

  The fin-like sealing portion 24 of the vacuum heat insulating material 20A is arranged so as to be folded inward on the lower temperature side, as in the first embodiment. Therefore, the sealing part 24 is located between the main body of the vacuum heat insulating material 20 </ b> A and the foam heat insulating panel 30 </ b> B constituting the second heat insulating layer 112. Similarly to the first embodiment, the first heat insulating layer 111, the second heat insulating layer 112, and the third heat insulating layer 113 are fixed to the container housing 110 by a fastening member 13 including a bolt 13a and a nut 13b. ing. In addition, since the basic structure of the foam heat insulation panel 30B is the same as that of the foam heat insulation panel 30A demonstrated in the said Embodiment 1, the description is abbreviate | omitted.

  Thus, in this Embodiment, the 1st heat insulation layer 111 and the 2nd heat insulation layer 112 are comprised as a heat insulation layer isolate | separated completely independently. Therefore, an air layer is formed between these heat insulating layers, and material continuity is broken. Thereby, since the cold temperature from the container housing | casing 110 is interrupted | blocked by the double inner side heat insulation layer (the 1st heat insulation layer 111 and the 2nd heat insulation layer 112), the leak of cold temperature can be suppressed effectively. As a result, the heat insulation structure 105 as a whole can ensure good heat insulation performance while effectively utilizing the heat insulation performance of the vacuum heat insulating material 20A.

  In the present embodiment, the position of the seam of the first heat insulating layer 111, the position of the seam of the second heat insulating layer 112, and the position of the seam of the third heat insulating layer 113 are all different. Specifically, when a projection view is assumed from the inside to the outside of the container housing 110, the joint of the outer third heat insulating layer 113 (the butt portion between the vacuum heat insulating materials 20A) is the inner second heat insulating. The seam of the layer 112 (the abutting portion between the foam heat insulation panels 30B) is shifted without overlapping, and the seam of the second heat insulation layer 112 is connected to the seam of the first heat insulation layer 111 (foam heat insulation panel 30B). The positions are not overlapped with each other. Alternatively, the abutting portion between the vacuum heat insulating materials 20 </ b> A is located at a position shifted from the extension line of the abutting portion between the foam heat insulating panels 30 </ b> B constituting the second heat insulating layer 112, and the foam constituting the second heat insulating layer 112. The abutting part between the body heat insulating panels 30B can also be expressed as being shifted from the extension line of the abutting part between the foam heat insulating panels 30B constituting the first heat insulating layer 111.

  Here, in the configuration shown in FIG. 6, the first heat insulating layer 111 and the second heat insulating layer 112 are both configured by the same type of foam heat insulating panel 30 </ b> B. The heat insulating panel constituting 111 and the heat insulating panel constituting the second heat insulating layer 112 may be different. For example, in the configuration shown in FIG. 7, the thermal insulation panel constituting the first thermal insulation layer 111 is the foam thermal insulation panel 30 </ b> B made of polystyrene foam (especially EPS) as in FIG. 6, but constitutes the second thermal insulation layer 112. The heat insulating panel is a foam heat insulating panel 30C made of urethane foam.

  Since the urethane foam foam heat insulation panel 30C has a lower thermal conductivity than the polystyrene foam foam heat insulation panel 30B, the second heat insulation layer 112 has better heat insulation performance than the first heat insulation layer 111. It will be. Thereby, since the heat insulation layer excellent in heat insulation performance is located outside rather than the inside, the inner first heat insulation layer 111 is well insulated by the outer second heat insulation layer 112.

  Therefore, since the atmospheric temperature in the region where the first heat insulating layer 111 exists is effectively held by the second heat insulating layer 112, the low temperature state of the first heat insulating layer 111 is well maintained, It can suppress effectively that cold temperature leaks outside. In addition, at this time, since the joint of the first heat insulating layer 111 is covered with the foam heat insulating panel 30C constituting the second heat insulating layer 112, it is possible to effectively suppress the leakage of cold temperature from the joint.

  Moreover, the 1st heat insulation layer 111 being heat-insulated favorably by the 2nd heat insulation layer 112 will improve the heat insulation performance of an inner side heat insulation layer. Thereby, the possibility that the inner side surface of the vacuum heat insulating material 20A is exposed to a lower temperature can also be suppressed. Therefore, warp deformation of the vacuum heat insulating material 20A, embrittlement (or damage) of the outer packaging material 22 serving as the inner surface can be effectively suppressed. As a result, the reliability of the heat insulating structure 105 can be improved.

  Note that the heat insulating performance of the second heat insulating layer 112 may not be clearly superior to the heat insulating performance of the first heat insulating layer 111, but may be comparable. Therefore, the second heat insulating layer 112 only needs to have a heat insulating performance equal to or higher than that of the first heat insulating layer 111. Therefore, the thermal insulation panel used for the second thermal insulation layer 112 is not necessarily different from the thermal insulation panel used for the first thermal insulation layer 111. The heat insulating panel used for the second heat insulating layer 112 may be made of the same material as the heat insulating panel used for the first heat insulating layer 111. For example, the heat insulating performance is improved by changing the foaming density. It can also be made.

  Also in the present embodiment, as shown in FIG. 8, the vacuum heat insulating material 20 </ b> A is not mechanically fastened by the fastening member 13 but is bonded and fixed to the foam heat insulating panel 30 </ b> A by the known adhesive 16. May be. Note that the type of the adhesive 16, the bonding location, and the like are the same as in the modification of the first embodiment (see FIG. 5).

  Furthermore, in the present embodiment, as shown in FIG. 9, the metal mesh 17 is provided between the first heat insulating layer 111 and the second heat insulating layer 112 and between the second heat insulating layer 112 and the third heat insulating layer 113. It may be provided. The metal mesh 17 functions as a member for supporting the fastening member 13 between the heat insulating layers. In the configuration shown in FIG. 9, a bolt that penetrates the metal mesh 17 to the nut 13 b fixed to the container housing 110. The foam heat insulating panel 30B and the vacuum heat insulating material 20A are fixed by tightening 13a. In addition, when providing the metal mesh 17 between each heat insulation layer, even if the volt | bolt 13a does not penetrate the vacuum heat insulating material 20A, it may be located between adjacent vacuum heat insulating materials 20A (between butt portions). Good.

  Moreover, in this Embodiment, although the end surface (side surface of a butt | matching site | part) of the edge part of the foam heat insulation panel 30B is a flat surface, this invention is not limited to this, It demonstrates in the said Embodiment 1. FIG. The edge part which has a level | step difference may be sufficient like 30A of foamed heat insulation panels. In this case, the abutting portion between the foam heat insulation panels 30B partially has a multilayer structure of four or more layers, and it is possible to more effectively suppress the leakage of cold temperature from the joint.

(Embodiment 3)
The vacuum heat insulating material 20A used in the first or second embodiment is the outer packaging material 22 having the same configuration on the outer surface and the inner surface. However, the present invention is not limited to this, and for example, shown in FIG. As described above, among the outer packaging material 22, the inner outer packaging material constituting the inner side surface may be configured to have higher low temperature resistance than the outer outer packaging material constituting the outer side surface. In the third embodiment, the vacuum heat insulating material 20B having such a configuration will be described with reference to FIG.

  For example, the vacuum heat insulating material 20B shown in FIG. 10 is basically the same as the vacuum heat insulating material 20A described in the first embodiment (see FIG. 3), and the outer laminated sheet 220A on the upper side in FIG. Similar to the laminated sheet 220 described in the first embodiment, it has a three-layer structure of a surface protective layer 221 made of nylon film, a gas barrier layer 222 made of aluminum foil, and a heat welding layer 223 made of low-density polyethylene film. .

  On the other hand, the inner laminated sheet 220B on the lower side in the figure is the same as the outer laminated sheet 220A in the surface protective layer 221 and the heat welding layer 223, but instead of the gas barrier layer 222 made of aluminum foil, aluminum vapor deposition is performed. This is a low temperature resistant gas barrier layer 226 composed of layers. Alternatively, although not shown, the inner laminated sheet 220B may have a structure in which the gas barrier layer 222 made of aluminum foil is multilayered.

  The inner side surface of the vacuum heat insulating material 20A is affected by a very low cooling temperature inside the container housing 110, although an inner heat insulating layer such as the foam heat insulating panel 30A or the foam heat insulating panel 30B is interposed. Therefore, the inner laminated sheet 220B (inner outer packaging material) constituting the inner surface is configured to have higher low-temperature resistance than the outer laminated sheet 220A (outer outer packaging material) constituting the outer surface. For example, an aluminum vapor-deposited layer or a multilayered aluminum foil is superior in low-temperature resistance compared to a single-layer aluminum foil. Thereby, since the low temperature tolerance of an inner outer packaging material improves, the embrittlement of the inner surface of the vacuum heat insulating material 20B can be suppressed favorably.

  In addition, a single-layer aluminum foil is less expensive than an aluminum vapor-deposited layer, and a single-layer aluminum foil can be formed with less material than a multilayered aluminum foil. Therefore, the outer outer packaging material can be made of a material that is relatively cheaper than the inner outer packaging material, or can be made of a small amount of material. Therefore, an increase in the manufacturing cost of the vacuum heat insulating material 20B can be effectively suppressed.

  Furthermore, an aluminum vapor deposition layer or a multilayered aluminum foil has higher heat insulation performance than a single-layer aluminum foil. Therefore, in the vacuum heat insulating material 20B, the heat insulating performance of the inner side surface can be improved, so that the heat insulating performance of the entire heat insulating structure 105 can be improved.

(Embodiment 4)
In the first or second embodiment, the third heat insulating layer 113 is composed of the single-layer vacuum heat insulating material 20A. However, the present invention is not limited to this, and for example, as shown in FIG. You may be comprised with the above vacuum heat insulating material 20A. In the fourth embodiment, the heat insulating structure 105 having such a configuration will be described with reference to FIG.

  In the configuration shown in FIG. 11, the first heat insulating layer 111 and the second heat insulating layer 112 are configured by the foam heat insulating panel 30 </ b> B as in the second embodiment, and the third heat insulating layer 113 is also the same as that in the first or second embodiment. Similarly, it is composed of the vacuum heat insulating material 20A (see FIG. 6), but unlike the second embodiment, the layer of the vacuum heat insulating material 20A is doubled.

  In this configuration, the second-layer vacuum heat insulating material 20A is arranged so as to be shifted from the first-layer vacuum heat insulating material 20A. Therefore, the butted portion between the first-layer vacuum heat insulating materials 20A and the second-layer vacuum heat insulating material 20A. They do not overlap with each other's butting site. Thereby, while being able to suppress the leak of cold temperature from the butt | matching site | part of 20 A of vacuum heat insulating materials, the heat transfer from the outside air via the butt | matching site | part can also be suppressed. Thereby, heat transfer inside and outside the container housing 110 can be reduced, and the ambient temperature in the region where the inner heat insulating layer (the first heat insulating layer 111 and the second heat insulating layer 112) is present can be effectively maintained. The heat insulation performance of the entire structure 105 can be further improved.

  In the present embodiment, the vacuum heat insulating material 20A described in the first embodiment is used for the third heat insulating layer 113, but the vacuum heat insulating material 20B described in the third embodiment is used instead. May be used. The third heat insulating layer 113 may have a multilayer structure in which the vacuum heat insulating material 20A (or the vacuum heat insulating material 20B) is laminated in a triple layer or more.

(Embodiment 5)
In the said Embodiment 1, 2, or 4, although the heat insulation structure 105 was comprised from the 1st heat insulation layer 111, the 2nd heat insulation layer 112, and the 3rd heat insulation layer 113, this invention is not limited to this. As shown in FIG. 12, the heat insulating structure 105 may include a fourth heat insulating layer 114. In the fifth embodiment, the heat insulating structure 105 having such a configuration will be described with reference to FIG.

  In the configuration shown in FIG. 12, the first heat insulating layer 111 and the second heat insulating layer 112 are formed of the foam heat insulating panel 30B as in the second embodiment, and the third heat insulating layer 113 is also the same as that of the first or second embodiment. Similarly, it is composed of the vacuum heat insulating material 20A (see FIG. 6), but the fourth heat insulating layer 114 is further provided outside the third heat insulating layer 113 by the foam heat insulating panel 30D. The joint of the fourth heat insulation layer 114, that is, the butted portion between the foam heat insulation panels 30D is shifted so as not to overlap the position of the joint of the third heat insulation layer 113 inside.

  In addition, the specific structure of the foam heat insulation panel 30D is not specifically limited, What is necessary is just to be comprised with the material similar to the foam heat insulation panel 30A or 30B illustrated in the said Embodiment 1 or 2. FIG. Moreover, as illustrated in FIG. 7 in the second embodiment, the first heat insulating layer 111, the second heat insulating layer 112, and the fourth heat insulating layer 114 may be formed of heat insulating panels made of different materials.

  By providing the fourth heat insulating layer 114 on the outer side of the third heat insulating layer 113, it is possible to suppress the leakage of cold temperature from the butt portion between the vacuum heat insulating materials 20A, and from outside air via the butt portion between the vacuum heat insulating materials 20A. Heat transfer can also be suppressed. Thereby, heat transfer inside and outside the container housing 110 can be reduced, and the ambient temperature in the region where the inner heat insulating layer (the first heat insulating layer 111 and the second heat insulating layer 112) is present can be effectively maintained. The heat insulation performance of the entire structure 105 can be further improved.

  In the present embodiment, the fourth heat insulating layer 114 is provided outside the third heat insulating layer 113, but a further outer heat insulating layer such as a fifth heat insulating layer may be provided. Moreover, although the vacuum heat insulating material 20A demonstrated in the said Embodiment 1 is used for the 3rd heat insulation layer 113, it may replace with this and the vacuum heat insulating material 20B demonstrated in the said Embodiment 3 may be used. Furthermore, you may laminate | stack alternately the heat insulation layer by the foam heat insulation panel 30B (or foam heat insulation panel 30A), and the heat insulation layer by the vacuum heat insulating material 20A.

  Furthermore, the first heat insulating layer 111 and / or the second heat insulating layer 112 may be multilayered. In other words, the inner heat insulating layer provided between the third heat insulating layer 113 and the container housing 110 may be two layers (the first heat insulating layer 111 and the second heat insulating layer 112), or three or more layers. There may be. Further, the outer heat insulating layer is not limited to the third heat insulating layer 113 constituted only by the vacuum heat insulating material 20A, and may be formed in a multilayer structure.

(Embodiment 6)
In this Embodiment 6, it is applicable to the said Embodiments 1-5, About the vacuum heat insulating material 20C which has an explosion-proof structure which suppresses or prevents a rapid deformation, with reference to FIG. 13A-FIG. This will be specifically described.

[Vacuum insulation with explosion-proof structure]
The vacuum heat insulating material 20C according to the present embodiment has the same configuration as the vacuum heat insulating material 20A described in the first embodiment or the vacuum heat insulating material 20B described in the third embodiment, and as illustrated in FIG. 13A. , A core material 21, an outer packaging material (outer coating material) 22, and an adsorbent 23. The core material 21 is a fibrous member made of an inorganic material, and is enclosed inside the outer packaging material 22 in a reduced-pressure sealed state (substantially vacuum state). The outer packaging material 22 is a bag-shaped member having a gas barrier property. In the present embodiment, the two laminated sheets 220 are opposed to each other and the periphery thereof is sealed by the sealing portion 24 to form a bag shape. Yes.

  The core material 21 should just be comprised with the fiber (inorganic fiber) which consists of inorganic materials. Specific examples include glass fiber, ceramic fiber, slag wool fiber, rock wool fiber, and the like. Moreover, since it is preferable to shape | mold the core material 21 in plate shape, you may also contain a well-known binder material, powder, etc. other than these inorganic fiber. These materials contribute to improvement of physical properties such as strength, uniformity and rigidity of the core material 21.

  In addition, as the core material 21, known fibers other than inorganic fibers may be used, but in the present embodiment, the average fiber diameter is in the range of 4 μm to 10 μm as inorganic fibers typified by glass fibers and the like. Inside glass fibers (glass fibers having a relatively large fiber diameter) are used, and such glass fibers are fired and used as the core material 21.

  Thus, if the core material 21 is an inorganic fiber, the fall of the vacuum degree by residual gas being discharge | released from the component of the core material 21 inside the vacuum heat insulating material 20C can be reduced. Furthermore, if the core material 21 is an inorganic fiber, the water absorption (hygroscopicity) of the core material 21 becomes low, so that the moisture content inside the vacuum heat insulating material 20C can be kept low.

  In addition, by firing the inorganic fiber, even if the outer packaging material 22 is broken or damaged due to some influence, the core material 21 does not swell greatly, and the shape as the vacuum heat insulating material 20C is maintained. be able to. Specifically, for example, when inorganic fibers are sealed as the core material 21 without firing, the swelling at the time of bag breaking can be two to three times that before bag breaking depending on various conditions. On the other hand, by firing inorganic fibers, the expansion at the time of bag breaking can be suppressed to 1.5 times or less. Therefore, by subjecting the inorganic fibers to be the core material 21 to the firing treatment, it is possible to effectively suppress the expansion at the time of bag breakage or breakage, and improve the dimension retention of the vacuum heat insulating material 20C.

  In addition, the firing condition of the inorganic fiber is not particularly limited, and various known conditions can be suitably used. Moreover, although baking of inorganic fiber is a particularly preferable treatment in the present invention, it is not an essential treatment.

  In the present embodiment, the laminated sheet 220 has a configuration in which three layers of a surface protective layer 221, a gas barrier layer 222, and a heat welding layer 223 are laminated in this order. The surface protective layer 221 is a resin layer for protecting the outer surface of the vacuum heat insulating material 20C. For example, a known resin film such as a nylon film, a polyethylene terephthalate film, or a polypropylene film is used, but is not particularly limited. The surface protective layer 221 may be composed of only one type of film, or may be composed of a plurality of laminated films.

  The gas barrier layer 222 is a layer for preventing outside air from entering the inside of the vacuum heat insulating material 20C, and a known film having gas barrier properties can be suitably used. Examples of the film having a gas barrier property include metal foils such as aluminum foil, copper foil, and stainless steel foil, vapor-deposited films in which metal or metal oxide is vapor-deposited on a resin film serving as a substrate, and further on the surface of the vapor-deposited film. Although the film etc. which gave the well-known coating process are mentioned, it is not specifically limited. Examples of the base material used for the vapor deposition film include a polyethylene terephthalate film or an ethylene-vinyl alcohol copolymer film, and examples of the metal or metal oxide include aluminum, copper, alumina, and silica. There is no particular limitation.

  The heat welding layer 223 is a layer for bonding the laminated sheets 220 to face each other, and also functions as a layer for protecting the surface of the gas barrier layer 222. That is, one surface (outer surface) of the gas barrier layer 222 is protected by the surface protective layer 221, while the other surface (inner surface, back surface) is protected by the heat welding layer 223. Since the core material 21 and the adsorbent 23 are sealed inside the vacuum heat insulating material 20C, the influence on the gas barrier layer 222 by the objects inside these is prevented or suppressed by the heat welding layer 223. Examples of the heat welding layer 223 include a film made of a thermoplastic resin such as low density polyethylene, but are not particularly limited.

  The laminated sheet 220 may include a layer other than the surface protective layer 221, the gas barrier layer 222, and the heat welding layer 223. Moreover, the gas barrier layer 222 and the heat welding layer 223 may be comprised only by one type of film similarly to the surface protective layer 221, and may be comprised by laminating | stacking a some film. That is, the laminated sheet 220 has one surface of the pair of surfaces (front and back surfaces) that is the heat-welded layer 223 and a gas barrier layer 222 in the multilayer structure (or any of the multilayer structures). The specific configuration is not particularly limited as long as the condition that the layer has gas barrier properties is satisfied.

  In the present embodiment, the laminated sheet 220 is formed as a bag-like outer packaging material 22 by thermally welding most of the peripheral edge in a state where two heat-welding layers 223 are arranged to face each other. Good. Specifically, for example, as shown in FIG. 14, a part of the periphery of the laminated sheet 220 (upper left side as viewed in FIG. 14) is left as the opening 25, and the periphery of the periphery excluding the opening 25 is left. What is necessary is just to heat-weld the remainder so that a center part (part in which the core material 21 is accommodated) may be surrounded.

  The adsorbent 23 penetrates slightly from the residual gas (including water vapor) released from the fine voids of the core material 21 after the core material 21 is sealed under reduced pressure inside the outer packaging material 22, the sealing portion 24, and the like. The outside air (including water vapor) is absorbed and removed. The specific kind of the adsorbent 23 is not particularly limited, and known materials including zeolite, calcium oxide, silica gel and the like can be suitably used.

  Here, the adsorbent 23 does not have a physical adsorption action, but preferably has a chemical adsorption action (chemical adsorption type), and the adsorbent 23 does not generate heat due to adsorption of residual gas (non-heat generation). A non-flammable material.

  In the present embodiment, as the adsorbent 23, a powdery ZSM-5 type zeolite encapsulated in a known packaging material is used. If the ZSM-5 type zeolite is in a powder form, the surface area becomes large, so that the gas adsorption ability can be improved.

  Further, from the viewpoint of improving nitrogen adsorption characteristics at room temperature, among ZSM-5 type zeolite, at least 50% or more of the copper sites of ZSM-5 type zeolite are copper monovalent sites, and copper Among the monovalent sites, it is preferable to use those in which at least 50% or more are oxygen tricoordinate copper monovalent sites. Thus, if the ZSM-5 type zeolite has an increased ratio of oxygen monocoordinated copper monovalent sites, the amount of adsorption of air under reduced pressure can be greatly improved.

  ZSM-5 type zeolite is a gas adsorbent having a chemical adsorption action. For this reason, for example, even if various environmental factors such as a temperature rise occur and may have some influence on the adsorbent 23, it is substantially prevented that the gas once adsorbed is re-released. Therefore, when handling the flammable fuel or the like, even if the adsorbent 23 adsorbs the flammable gas due to some influence, the gas is not re-released due to the subsequent temperature rise or the like. As a result, the explosion-proof property of the vacuum heat insulating material 20C can be further improved.

  Moreover, since ZSM-5 type zeolite is a nonflammable gas adsorbent, the adsorbent 23 in the present embodiment is substantially composed of a nonflammable material. Therefore, the flammable material is not used inside the vacuum heat insulating material 20C including the core material 21, and the explosion-proof property can be further improved. Examples of the inorganic gas adsorbent include lithium (Li) and the like, and lithium is a combustible material. And in this Embodiment, the spherical tank 101 for LNG is illustrated as a use of the vacuum heat insulating material 20C (refer Embodiment 1 and FIG. 1A, FIG. 1B). Therefore, if such a flammable material is used as the adsorbent 23, it is needless to say that it is not suitable for a container that handles flammable fuel such as LNG, even if it is assumed that a large explosion does not occur. Yes.

  As described above, if the adsorbent 23 is a chemical adsorption type, the adsorbed residual gas is not easily separated as compared with the physical adsorption type, so that the degree of vacuum inside the vacuum heat insulating material 20C can be maintained well. it can. In addition, since the residual gas is not desorbed, it is possible to effectively prevent the residual gas from expanding inside the outer packaging material 22 and deforming the vacuum heat insulating material 20C. Therefore, the explosion-proof property and stability of the vacuum heat insulating material 20C can be improved.

  Further, if the adsorbent 23 is a non-heat-generating material, a non-flammable material, or a material that satisfies both, the adsorbent can be used even if foreign matter enters the inside due to damage to the outer packaging material 22 or the like. It is possible to avoid the possibility of heat generation or combustion of 23. Therefore, the explosion-proof property and stability of the vacuum heat insulating material 20C can be improved.

  As described above, the adsorbent 23 preferably has a chemical adsorption type that chemically adsorbs the residual gas, a non-exothermic property that does not generate heat due to the adsorption of the residual gas, or a chemical adsorption type and non-exothermic configuration. This configuration corresponds to a configuration example 2 of an explosion-proof structure of the vacuum heat insulating material 20C described later.

  The specific manufacturing method of 20 C of vacuum heat insulating materials is not specifically limited, A well-known manufacturing method can be used suitably. In this embodiment, as described above, the bag-shaped outer packaging material 22 is obtained by heat-sealing the peripheral edge portion so that the two laminated sheets 220 are overlapped to form the opening 25. Therefore, as shown in FIG. 14, the core material 21 and the adsorbent 23 may be inserted into the outer packaging material 22 from the opening 25 and decompressed in a decompression facility such as a decompression chamber. Thereby, the inside (bag interior) of the bag-shaped outer packaging material 22 is sufficiently depressurized from the opening 25 to be in a substantially vacuum state.

  Then, if the opening 25 is hermetically sealed by thermal welding as well as the other peripheral portions, the vacuum heat insulating material 20C is obtained. Various conditions such as thermal welding and reduced pressure are not particularly limited, and various known conditions can be suitably employed. Further, the outer packaging material 22 is not limited to a configuration using two laminated sheets 220. For example, if one laminated sheet 220 is folded in half and both side edges are heat welded, a bag-like outer packaging material 22 having an opening 25 can be obtained. Alternatively, the laminated sheet 220 may be formed into a cylindrical shape and one opening may be sealed.

  In any case, in the present embodiment, the outer packaging material 22 only has to have the opening 25 whose inner surface is the thermal welding layer 223. Thereby, the opening part 25 can be sealed by heat-welding in the state which heat-welded layers 223 were contacted. Therefore, if the opening 25 is sealed after decompression, the inside of the bag can be sealed.

  As shown in FIG. 13A, the sealing portion 24 obtained by thermally welding the peripheral edge portion of the outer packaging material 22 may have a configuration in which the opposed heat-welding layers 223 are welded to each other to form a welding portion. Here, in the present embodiment, as shown in FIG. 13B, the sealing portion 24 preferably includes at least a plurality of thin portions 241, and more preferably includes a thick portion 242. The thin-walled portion 241 is a portion where the thickness of the welded portion between the heat-welded layers 223 is smaller than the thickness of the heat-welded layer 223 simply overlapped, and the thick-walled portion 242 is welded between the heat-welded layers 223. It is a site | part with a large thickness of a site | part. When the sealing part 24 includes at least the thin part 241, it becomes difficult for outside air or the like to enter the vacuum heat insulating material 20 </ b> C from the sealing part 24.

  Since a slight end surface of the heat-welding layer 223 is exposed at the peripheral edge of the outer packaging material 22, there is a possibility that outside air may enter through the sealing portion 24. Although the gas barrier layer 222 of the outer packaging material 22 cannot completely block the intrusion of outside air, the gas (including water vapor) permeability is extremely low as compared with the heat welding layer 223. Therefore, it can be considered that most of the outside air entering the inside of the vacuum heat insulating material 20 </ b> C is through the sealing portion 24.

  If the sealing part 24 includes the thin part 241, the permeation resistance of the outside air entering from the end face of the heat welding layer 223 increases. Therefore, intrusion of outside air can be effectively suppressed, and the possibility that the outside air that has entered inside the outer packaging material 22 expands and the vacuum heat insulating material 20C is deformed can be reduced. Furthermore, as shown in FIG. 13B, if the thick portions 242 and the thin portions 241 are alternately arranged so that the thin portions 241 are positioned between the thick portions 242, the strength of the sealing portion 24 is improved. In addition, the heat conduction between the gas barrier layers 222 due to the thin wall portion 241 becoming a heat bridge can be effectively suppressed.

  In addition, it does not specifically limit about the formation method of the sealing part 24 including two or more thin parts 241 and the thick part 242. As a typical forming method, a method disclosed in Patent Document 1 can be given. In addition, the number of the thin portions 241 and the thick portions 242 is not particularly limited, and may be about 4 to 6 thin portions 241 depending on the width of the peripheral portion that becomes the sealing portion 24.

[Specific configuration of explosion-proof structure]
20 C of vacuum heat insulating materials which concern on this Embodiment have an explosion-proof structure which suppresses or prevents the rapid deformation | transformation of the said vacuum heat insulating material 20C, when a residual gas expand | swells inside the outer packaging material 22. FIG. Although the specific explosion-proof structure is not particularly limited, typically, for example, Configuration Example 1: Configuration in which the foamed resin layer 11 covering the vacuum heat insulating material 20C is formed so that no organic foaming agent remains after foaming. Configuration Example 2: The adsorbent 23 enclosed with the core material 21 inside the outer packaging material 22 is a chemical adsorption type that chemically adsorbs the residual gas, or is non-exothermic that does not generate heat due to the adsorption of the residual gas. Or, a configuration that is a chemisorption type and non-heat generation, or configuration example 3: a configuration in which the outer packaging material 22 includes an expansion relaxation portion that releases residual gas to the outside and relaxes expansion, and the like.

  The configuration example 1 will be described together with a modified example of the vacuum heat insulating material panel described later. Further, since the configuration example 2 corresponds to a preferable example of the adsorbent 23 described above, a specific description thereof is omitted. In the following, the expansion relaxation part of the configuration example 3 will be specifically described. The specific configuration of the expansion relaxation portion is not particularly limited, but representatively, check valves 26A and 26B as shown in FIG. 15 and FIG. 16, or a strength reduction portion 243 as shown in FIG. .

  For example, the check valve 26 </ b> A shown in FIG. 15 has a cap-like configuration that closes a valve hole 260 provided in a part of the outer packaging material 22. The valve hole 260 is provided so as to penetrate the inside and outside of the outer packaging material 22, and the cap-like check valve 26A is made of an elastic material such as rubber. Normally, the valve hole 260 is closed by the check valve 26 </ b> A, so that outside air can be substantially prevented from entering the outer packaging material 22. Even if the outer packaging material 22 contracts due to a change in ambient temperature, and the inner diameter of the valve hole 260 changes accordingly, the check valve 26A is made of an elastic material, so that the valve hole 260 can be closed well. . If the residual gas expands inside the outer packaging material 22, the check valve 26A is easily removed from the valve hole 260 as the internal pressure increases, and the residual gas is released to the outside.

  Further, the check valve 26 </ b> B shown in FIG. 16 has a valve-like structure configured to close the cut portion 261 formed in a part of the outer packaging material 22. Specifically, the check valve 26B includes an outer portion 262 that functions as a valve body, an inner portion 263 that functions as a valve seat, and an adhesive layer 264 that adheres so that the outer portion 262 does not peel from the inner portion 263. I have. The outer portion 262 has a shape in which a part of the outer packaging material 22 extends in a band shape so as to cover the top of the cut portion 261 formed in the outer packaging material 22. The inner portion 263 is a part of the outer packaging material 22 adjacent to the cut portion 261 and overlaps the outer portion 262.

  Usually, the outer part 262 which is a valve body is seated on the inner part 263 which is a valve seat, and the notch part 261 which is a valve hole is closed. At this time, since the belt-shaped outer portion 262 is bonded to the inner portion 263 by the adhesive layer 264, the outer portion 262 is prevented from rolling up and a stable seating state (closed state) is maintained. This substantially prevents outside air from entering the outer packaging material 22. In the unlikely event that the residual gas expands inside the outer packaging material 22, the adhesive layer 264 slightly bonds the outer portion 262 and the inner portion 263, and is therefore a valve body as the internal pressure increases. The outer part 262 is easily swung up from the inner part 263 which is a valve seat. As a result, the internal residual gas is released to the outside.

  Moreover, the strength reduction site | part 243 shown in FIG. 17 is a site | part where the welding area of a part of welding site | part 240 of the heat welding layers 223 is small in the sealing part 24. FIG. In FIG. 17, in both the schematic plan view and the upper and lower partial cross-sectional views, the welding portion 240 is illustrated as a blackened region. In the standard sealing portion 24, as shown in the partial cross-sectional view in the upper part of FIG. 17, a welding site 240 is formed so as to cover the entire sealing portion 24. On the other hand, as shown in the partial cross-sectional view in the lower part of FIG. 17, in the strength-decreasing portion 243, the inner side (core material 21 side) of the sealing portion 24 is not welded. Is also getting smaller.

  Since the strength decreasing portion 243 is a part of the welding portion 240 in the sealing portion 24, the laminated sheets 220 that are the outer packaging material 22 are overlapped and sealed. Therefore, outside air basically cannot enter the outer packaging material 22 from the sealing portion 24. If the residual gas expands inside the outer packaging material 22, the pressure due to the increase in the internal pressure tends to concentrate on the strength-decreasing portion 243. Thereby, the heat welding layers 223 constituting the welding part 240 are peeled off, and the residual gas is released to the outside.

  Here, the strength reduction portion is not limited to a configuration in which the welding area of the welding portion 240 is partially reduced like the strength reduction portion 243 illustrated in FIG. 17, and the welding strength is partially reduced even if the welding area is the same. It may be a configuration. For example, when the heat-welding layers 223 are heat-welded, only a part of the heat may be reduced to weaken the degree of welding at the welding portion 240. Or you may provide an intensity | strength fall site | part other than the welding location 240, ie, the welding location of the heat welding layers 223. FIG. For example, a portion where the lamination strength is partially reduced may be formed between the heat-welding layer 223 and the gas barrier layer 222 constituting the laminated sheet 220, and the strength reduction portion may be used.

  Furthermore, a part of the heat-welded layer 223 may be formed of a material having a lower welding strength than other parts, thereby forming a reduced strength part. For example, as described above, low-density polyethylene can be preferably used as the heat-welding layer 223, but a part of the heat-welding layer 223 is made of high-density polyethylene, ethylene-vinyl alcohol copolymer, or amorphous polyethylene. It may be terephthalate or the like. Since these polymer materials have a welding strength lower than that of low density polyethylene, they can be suitably used for forming a reduced strength portion.

  Alternatively, as a method of forming the strength-decreasing portion, an adhesive having a low adhesive strength is partially applied to a part of the region to be the welded portion 240 of the heat-welded layer 223 to partially reduce the thickness of the welded portion 240 between the heat-welded layers 223. A structure in which the heat-welding layer 223 is partially peeled and the gas barrier layers 222 are directly heat-welded to each other in the region that becomes the sealing portion 24 of the laminated sheet 220 that interposes the gas barrier layer can also be employed.

  In the present embodiment, since the vacuum heat insulating material 20C is provided in the third heat insulating layer 113 (or the outer heat insulating layer), the vacuum heat insulating material 20C is exposed to a harsh environment when an accident or the like occurs. There is a risk. In this case, there is a possibility that the vacuum heat insulating material 20C is exposed to a harsh environment and the residual gas inside expands. On the other hand, if the vacuum heat insulating material 20C includes the expansion relaxation part as described above, even if the vacuum heat insulating material 20C located in the outermost layer is exposed to a harsh environment and the internal residual gas expands, The deformation of the vacuum heat insulating material 20C can be effectively avoided. Therefore, the explosion-proof property and stability of the vacuum heat insulating material 20C can be further improved.

(Embodiment 7)
In the said Embodiment 1-6, although the vacuum heat insulating material 20A, 20B, or 20C was used in the 3rd heat insulation layer 113, this invention is not limited to this, The vacuum heat insulating materials 20A-20C itself is a heat insulation panel. It may be configured as. In the seventh embodiment, a configuration in which the vacuum heat insulating material 20C described in the sixth embodiment is formed into a heat insulating panel will be specifically described with reference to FIGS. 18A, 18B, 19A, and 19B.

[Vacuum insulation panel]
In this invention, the vacuum heat insulating material panel 10 which can be used as the 3rd heat insulation layer 113 is comprised using 20C (or vacuum heat insulating material 20A, 20B) mentioned above. Specifically, as shown in FIGS. 18A and 18B, the vacuum heat insulating material panel 10 is completely covered with the outer packaging material 22 of the vacuum heat insulating material 20 </ b> C by the foamed resin layer 11.

  Although the foamed resin layer 11 should just be comprised with well-known foamed resin, such as a polyurethane or a polystyrene, Preferably, it is comprised by the styrene-type resin composition containing a polystyrene. The styrenic resin composition referred to here may be one containing polystyrene or a styrene copolymer as a resin component. Polystyrene is a polymer obtained by polymerizing only styrene as a monomer, and a styrene copolymer is a polymer obtained by polymerizing a compound having a chemical structure similar to styrene (styrene compound) as a monomer. It may be a copolymer obtained by copolymerizing a plurality of styrene compounds, or a copolymer obtained by copolymerizing a styrene compound (including styrene) and other monomer compounds. Good.

  Here, examples of the styrene compound include o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, vinyltoluene, t-butyltoluene, divinylbenzene and the like in addition to styrene. There is no particular limitation. Further, since the styrene copolymer may be a polymer using a styrene compound (including styrene) as a monomer component, it may contain a monomer compound other than the styrene compound as described above. However, generally, it is only necessary that 50 mol% or more of the styrene-based compound is contained in all the monomer components. Specific types of monomer compounds other than styrene compounds are not particularly limited, and known compounds copolymerizable with styrene (for example, olefin compounds such as ethylene, propylene, butene, butadiene, 2-methyl-propylene, etc.) ) Can be suitably used.

  Further, as the resin component used in the styrene resin composition, at least one kind of polystyrene or styrene copolymer (collectively referred to as styrene resin) may be used, but two or more kinds of styrene resins are used. May be. Furthermore, as the resin component, in addition to the styrene resin, a known resin, for example, an olefin resin such as a polyolefin or an olefin copolymer may be used in combination. At this time, styrene resin should just be 50 weight% or more among all the resin components contained in the foamed resin layer 11. FIG.

  The styrene resin composition may contain a known additive in addition to the resin component. Specific examples of additives include fillers, lubricants, mold release agents, plasticizers, antioxidants, flame retardants, ultraviolet absorbers, antistatic agents, reinforcing agents, etc. It is not limited. In addition, although the following organic foaming agent is used for formation of the foamed resin layer 11, in this specification, an organic foaming agent shall not be contained in the additive here.

  As described above, the styrene resin composition contains a known organic foaming agent. Specific examples of the organic blowing agent include saturated hydrocarbons such as propane, n-butane, isobutane, n-pentane, isopentane, neopentane, cyclopentane, and hexane; dimethyl ether, diethyl ether, methyl ethyl ether, and the like. Ether compounds; halogenated hydrocarbons such as methyl chloride, methylene chloride and dichlorodifluoromethane; These organic foaming agents may be used alone or in combination of two or more. Of these, saturated hydrocarbons such as n-butane are preferably used.

  The formation method of the foamed resin layer 11 is not particularly limited, and a styrene resin composition is prepared by mixing a styrene resin and other components, and an organic foaming agent by a known method, and obtaining the styrene resin composition What is necessary is just to accommodate a thing and the vacuum heat insulating material 20C in the shaping | molding die of the vacuum heat insulating material panel 10, and to foam an organic type foaming agent. At this time, in the mold, the styrene resin composition may be filled by a known method so that the foamed resin layer 11 is completely covered with the vacuum heat insulating material 20C.

  Although the specific form of a styrene resin composition is not specifically limited, Usually, what is necessary is just a foam bead. That is, the foamed resin layer 11 may be a so-called “bead method expanded polystyrene (EPS, Expanded Poly-Styrene)”. In this case, the foamed beads and the vacuum heat insulating material 20C may be accommodated in a mold, and the organic foaming agent may be foamed by steam heating. If the foamed resin layer 11 is EPS, a molded body (vacuum heat insulating material panel 10) in which foam beads are fused to each other by steam heating is obtained. In addition, the said material illustrated as the foamed resin layer 11 of the vacuum heat insulating material panel 10 can be used suitably also as a material of the foam heat insulating panels 30A-30D in Embodiment 1-6 mentioned above.

  As shown in FIG. 18A or FIG. 18B, the obtained vacuum heat insulating material panel 10 has a configuration in which a vacuum heat insulating material 20 </ b> C is included in the foamed resin layer 11. Thereby, the surface of the vacuum heat insulating material 20C can be protected. Moreover, since the vacuum heat insulating material panel 10 including the vacuum heat insulating material 20C is manufactured as a “molded product”, the shape and dimensions thereof can be standardized. Therefore, the vacuum heat insulating material panel 10 can improve the dimensional accuracy as the “heat insulating material” as compared with the vacuum heat insulating material 20 </ b> C having a configuration in which the core material 21 is accommodated in the outer packaging material 22.

  Moreover, in the present invention, the heat insulating material panel 10C is applied to the heat insulating container 104 such as the spherical tank 101 shown in FIGS. 1A, 1B, etc., but the surface of the vacuum heat insulating material panel 10 is protected, so that the heat insulating container 10C is protected. The reliability of 104 itself can be improved.

  For example, in this Embodiment, the vacuum heat insulating material panel 10 can be used as the 3rd heat insulation layer 113 used as the outer heat insulation layer of the heat insulation container 104 so that it may illustrate in the said Embodiment 1-5. This is because the vacuum heat insulating material 20 </ b> C having excellent heat insulating performance is arranged outside the heat insulating container 104 to effectively suppress the intrusion of heat from the outside. Here, in the LNG transport tanker 100, the vacuum heat insulating material 20C located outside the spherical tank 101 is required to have durability that can withstand contact with seawater.

  The laminated sheet 220 used for the outer packaging material 22 of the vacuum heat insulating material 20C is basically made of resin, but as described above, a metal foil or a metal vapor deposition film is used for the gas barrier layer 222. In general, when metals come into contact with seawater, they are easily corroded by various ions contained in the seawater. In the present embodiment, since the vacuum heat insulating material panel 10 has a structure in which the vacuum heat insulating material 20C is completely covered with the foamed resin layer 11, even if seawater enters the hull 102, the foamed resin layer 11 Contact of seawater with the vacuum heat insulating material 20C can be effectively avoided.

  Furthermore, as shown in FIG. 18A or FIG. 18B, the vacuum heat insulating material panel 10 is not composed only of the foamed resin layer 11 but includes the vacuum heat insulating material 20C inside, so that the heat insulating property is extremely excellent. ing. Therefore, it is possible to suppress an increase in the thickness of the third heat insulating layer 113 (or the thickness of the heat insulating structure 105) without reducing the heat insulating performance.

  In addition, since the foamed resin layer 11 protects the vacuum heat insulating material 20C, even if an impact or the like is applied to the vacuum heat insulating material panel 10, bag breakage or breakage of the vacuum heat insulating material 20C is effectively suppressed. be able to. Therefore, the vacuum heat insulating material panel 10 is not only resistant to foreign matter such as seawater or a severe environment such as manufacturing, but also resistant to physical shocks (resistance to heat). Impact property). As a result, the reliability of the vacuum heat insulating material 20C can be improved.

  Further, as described above, a styrene resin composition is preferably used for the foamed resin layer 11. In general, EPS has lower water absorption than foamed polyurethane (urethane foam) and the like, and its deterioration rate of heat insulation performance is small. Therefore, compared with the case where the foamed resin layer 11 is made of foamed polyurethane, the protection performance and heat insulation performance of the vacuum heat insulating material 20C are excellent. Furthermore, since the outer packaging material 22 of the vacuum heat insulating material 20C includes the sealing portion 24 described above, the vacuum heat insulating material 20C itself has good durability. Thereby, the vacuum heat insulating material panel 10 can exhibit not only the durability with respect to seawater but also sufficient durability against various environmental changes during manufacturing or maintenance of the spherical tank 101.

[Variation of vacuum insulation panel]
Here, as schematically shown in FIG. 18A, the skin layers 10 a and 10 b of the vacuum heat insulating material panel 10 are in a state where the foam beads are compressed and hardened as compared with the inside of the vacuum heat insulating material panel 10. On the other hand, as shown to FIG. 18B, the vacuum heat insulating material panel 10 may remove the skin layers 10a and 10b. In other words, the vacuum heat insulating material panel 10 may have a configuration in which the skin layers 10a and 10b are removed. Thereby, an organic foaming agent can be favorably removed from the foamed resin layer 11 of the vacuum heat insulating material panel 10.

  In general, in an EPS molded article, it is considered that the organic foaming agent is more excellent in heat insulation. However, the presence of the organic foaming agent may reduce the accuracy of the above-described leak inspection using helium. Moreover, if the organic foaming agent remains in the vacuum heat insulating material panel 10, the stability of the vacuum heat insulating material 20C may be affected by the organic foaming agent when the LNG transport tanker 100 encounters an accident. There can be sex. Therefore, the skin layers 10a and 10b of the vacuum heat insulating material panel 10 are removed. As a result, the portion where the foamed beads are hardened is removed, so that the organic foaming agent can be easily removed from the foamed resin layer 11. As a result, the possibility that the organic foaming agent remains in the EPS molded product can be effectively suppressed. That is, the removal of the skin layers 10a and 10b corresponds to the configuration example 1 of the explosion-proof structure of the vacuum heat insulating material 20C.

  Note that the skin layers 10a and 10b to be removed may be skin layers 10a (outer skin layers 10a) on at least the outer surface (front and back surfaces), and the side surfaces of the vacuum heat insulating material panel 10 in addition to the outer skin layers 10a. The skin layer 10b may also be removed. As a method for removing the skin layers 10a and 10b, the skin layers 10a and 10b may be cut off by a known cutter or the like used for cutting EPS. The method for removing the organic foaming agent after removing the skin layers 10a and 10b is not particularly limited, and a known method such as heating the vacuum heat insulating material panel 10 at a predetermined temperature and a predetermined time may be adopted.

  Here, whether or not the skin layers 10a and 10b have been cut off can be easily confirmed by simply comparing one surface of the foamed resin layer 11 with another surface. Specifically, the skin layers 10a and 10b and the inside of the foamed resin layer 11 have clearly different conditions such as the density of the foam beads, the hardness of the foam beads, and the surface roughness. Therefore, those skilled in the art can sufficiently confirm whether the surface of the foamed resin layer 11 is the skin layers 10a and 10b or the inner layer after being cut off.

  In addition, the “configuration in which the foamed resin layer 11 covering the vacuum heat insulating material 20C is formed so that no organic foaming agent remains after foaming”, which is the configuration example 1 of the explosion-proof structure, is only the removal of the skin layers 10a and 10b. It is not limited to. In the present embodiment, since the foamed resin layer 11 is formed by heating and foaming a raw material containing an organic foaming agent, the organic foaming agent can be removed by a known method after foaming. If possible, configuration example 1 of the explosion-proof structure can be realized.

  Moreover, as shown in FIG. 19A or 19B, in the vacuum heat insulating material panel 10, the vacuum heat insulating material 20C and the foamed resin layer 11 may be bonded and integrated. Thereby, even if the heat insulation panel 10 is exposed to high temperature and the vacuum heat insulating material 20C is thermally expanded, the possibility that a gap is generated between the foamed resin layer 11 and the vacuum heat insulating material 20C is suppressed. Therefore, the durability and stability of the vacuum heat insulating material panel 10 can be improved.

  For example, as shown in FIG. 19A, the vacuum heat insulating material 20C and the foamed resin layer 11 are bonded by the adhesive 12 applied to the surface of the vacuum heat insulating material 20C, or as shown in FIG. 19B, The outermost layer of the laminated sheet 220 used for the outer packaging material 22 is a “heat-welded surface protective layer 224” made of a resin having heat-weldability, and this heat-welded surface-protective layer 224 functions as an adhesive. May be.

  Specific types of the adhesive 12 or the heat-welded surface protective layer 224 are not particularly limited, and low-density polyethylene or the like can be used similarly to the heat-welded layer 223. Here, the adhesive 12 or the heat-welded surface protective layer 224 preferably has a heat resistance of 80 ° C. or higher. Thereby, it is possible to cope with a large temperature change at the time of manufacturing or maintaining the spherical tank 101.

  Furthermore, the method of melting the adhesive 12 or the heat-welded surface protective layer 224 and bonding the vacuum heat insulating material 20C and the foamed resin layer 11 is not particularly limited. For example, if the adhesive 12 is used, the adhesive 12 is applied to the outer surface of the vacuum heat insulating material 20C (outer packaging material 22), and a styrene resin composition (a preferable example is expanded beads) that is a raw material of the expanded resin layer 11 ), The adhesive 12 may be melted at the same time as the styrenic resin composition is foamed. When the heat-welded surface protective layer 224 is employed, the heat-welded surface protective layer 224 is heated while the vacuum heat insulating material 20C is covered with the styrene-based resin composition to foam the styrene-based resin composition. May be melted. Therefore, the adhesive 12 or the heat-welded surface protective layer 224 only needs to be made of a material that melts at the heating temperature of the raw material of the foamed resin layer 11.

(Embodiment 8)
Although the heat insulating container 104 according to the first to seventh embodiments is the spherical tank 101 provided in the LNG transport tanker 100, the present invention is not limited to this, for example, an LNG tank installed on land. Also good. In the eighth embodiment, such an LNG tank will be described with reference to FIG. 20 and FIG.

  FIG. 20 shows a ground type LNG tank 120. This ground type LNG tank 120 is provided with a spherical heat insulating container 124 as a tank body in the same manner as the spherical tank 101 of the first embodiment, and this heat insulating container 124 is supported on the ground 50 by the support structure 121. Has been. Although the support structure part 121 is comprised by the several support | pillar 122 provided in the perpendicular direction on the ground 50, and the brace 123 provided between support | pillars 122, it is not specifically limited.

  The heat insulating container 124 includes a container housing 126 that holds a low-temperature substance, and a heat insulating structure 125 that is provided outside the container housing 126. The specific configurations of the container housing 126 and the heat insulating structure 125 are as described in the first to seventh embodiments. In particular, the heat insulating structure 125 includes any one of the configurations of the first to seventh embodiments. Or the structure which combined the structure of these embodiment suitably can be employ | adopted suitably.

  FIG. 21 illustrates an underground LNG tank 130. The underground LNG tank 130 is provided with a cylindrical heat insulating container 134 inside a concrete structure 131 embedded in the ground 50. The heat insulating container 134 includes a container housing 136 for holding a cryogenic substance, And a heat insulating structure 135 provided outside the container housing 136. The concrete structure 131 is made of prestressed concrete, for example, and is installed in the ground so that most of it is below the ground 50. The concrete structure 131 is a support that supports the structure of the tank main body of the underground LNG tank 130, and also functions as a barrier that prevents LNG from leaking in case the tank main body is damaged.

  In addition, a roof portion 132 separate from the heat insulating container 134 is provided in the upper opening of the heat insulating container 134. The upper surface of the roof part 132 is a convex curved surface, and the lower surface is a flat surface. As with the heat insulating container 134, a heat insulating structure 135 is provided outside the roof portion 132, and a fibrous heat insulating material 133 is provided therein. Examples of the fibrous heat insulating material 133 include inorganic fibers used as the core material 21 of the vacuum heat insulating materials 20A to 20C. The specific configurations of the container housing 136 and the heat insulating structure 135 are as described in the first to seventh embodiments. In particular, the heat insulating structure 135 includes any one of the configurations of the first to seventh embodiments, Or the structure which combined the structure of these embodiment suitably can be employ | adopted suitably.

  Thus, the present invention can be applied not only to the LNG transport tanker 100 but also to the above-ground LNG tank 120 or the underground LNG tank 130. Here, each of the spherical tank 101 of the LNG transport tanker 100 and the tank body of the above-ground LNG tank 120 includes a spherical heat insulating container 104 or 124. In addition, the tank body of the underground LNG tank 130 includes a cylindrical heat insulating container 134 and a roof portion 132 having a convex curved surface.

  Therefore, the present invention can be satisfactorily applied to a heat insulating container having at least a curved shape such as a spherical shape, a cylindrical shape, and a roof portion having a curved surface. More preferably, it can be applied to a heat insulating container having a closed curved surface shape such as a spherical shape or a cylindrical shape, and it is particularly preferably applied to a heat insulating container having a spherical shape (including an elliptical spherical shape or a substantially spherical shape). be able to.

(Embodiment 9)
In any of the first to eighth embodiments, the low temperature substance held in the heat insulating container was LNG. However, the present invention is not limited to this, and the low temperature substance is a substance stored at a temperature lower than normal temperature. Any fluid may be used as long as it is maintained at a temperature that is 100 ° C. or more lower than room temperature. In the ninth embodiment, hydrogen gas is exemplified as a low-temperature substance other than LNG. An example of a hydrogen tank that liquefies and holds hydrogen gas will be specifically described with reference to FIG.

  As shown in FIG. 22, the hydrogen tank 140 according to the present embodiment is a container type, and basically described in the spherical tank 101 described in the first embodiment or described in the eighth embodiment. It has the same configuration as the above-ground type LNG tank 120. That is, the hydrogen tank 140 is provided with a heat insulating container 144 which is a tank body in a frame-shaped support body 141. The heat insulating container 144 includes a container housing 146 for holding a low-temperature substance, and the container housing 146. And a heat insulating structure 145 provided on the outside of the. The specific configurations of the container housing 146 and the heat insulating structure 145 are as described in the first to seventh embodiments. In particular, the heat insulating structure 145 has the configuration of any of the first to seventh embodiments, Or the structure which combined the structure of these embodiment suitably can be employ | adopted suitably.

  In general, liquefied hydrogen (liquid hydrogen) is a liquid at an extremely low temperature of −253 ° C., and its evaporability is about 10 times that of LNG. Therefore, in order to obtain an evaporation loss level equivalent to that of LNG for liquefied hydrogen, it is necessary to further improve the heat insulating performance (small thermal conductivity) of the heat insulating material. On the other hand, in this embodiment, since the heat insulating structure having the configuration described in the first to seventh embodiments is used, the hydrogen tank 140 can be further increased in heat insulation.

  In the present invention, the low-temperature substance held in the heat insulating container is not limited to LNG or hydrogen gas, and is a substance stored at a temperature lower than normal temperature (preferably, fluidity at a temperature lower than normal temperature by 100 ° C. or more. The fluid). Taking fluid as an example, fluids other than LNG and hydrogen gas may include liquefied petroleum gas (LPG), other hydrocarbon gases, or combustible gases containing these. Or it is various compounds conveyed by a chemical tanker etc., Comprising: The compound preserve | saved at the temperature below normal temperature may be sufficient. Furthermore, the heat insulating container applicable in the present invention may be a cryopreservation container used for medical or industrial purposes. Moreover, normal temperature should just be in the range of 20 degreeC +/- 5 degreeC (within the range of 15 to 25 degreeC).

  From the foregoing description, many modifications and other embodiments of the present invention are obvious to one skilled in the art. Accordingly, the foregoing description should be construed as illustrative only and is provided for the purpose of teaching those skilled in the art the best mode of carrying out the invention. The details of the structure and / or function may be substantially changed without departing from the spirit of the invention.

  The present invention will be described more specifically based on examples and comparative examples, but the present invention is not limited to this. Those skilled in the art can make various changes, modifications, and alterations without departing from the scope of the present invention.

(Calculation method of average heat transmissibility)
In the heat insulation containers of the following comparative examples or examples, the heat conductivity of each heat insulation layer constituting the heat insulation structure is determined according to the heat flow measurement method of JIS A 1412, ASTM C518, and ISO 8301. (EKO Instruments Co., Ltd.) Measured using a thermal conductivity measuring device (product number HC-074-300 or HC-074-066) manufactured by EKO Instruments Co., Ltd. At this time, the internal temperature of the heat insulating container was −160 ° C., and the outside air was 25 ° C. From the obtained thermal conductivity and the thickness of each heat insulating layer, the average heat transmissivity of the heat insulating structure was calculated by area weighted average.

Example 1
The heat insulation container of Example 1 was obtained by providing the heat insulation structure provided with a 1st heat insulation layer, a 2nd heat insulation layer, and a 3rd heat insulation layer in the outer side of the spherical container housing | casing made from aluminum. Among the heat insulating layers of the heat insulating structure, the first heat insulating layer and the second heat insulating layer are made of foamed polystyrene heat insulating panels, and the third heat insulating layer is the vacuum heat insulating material having the configuration described in the first embodiment. Was used. Table 1 shows the total thickness T of the heat insulating structure, the total thickness t1 of the first heat insulating layer and the second heat insulating layer, and the thickness t2 of the third heat insulating layer. The average heat transmissivity of this heat insulation container was computed by the said method. Table 1 shows the calculation result of the average heat transmissibility, the evaluation result of the heat insulation performance based on Comparative Example 1 described later, and the ratio of the thickness based on Comparative Example 1.

(Comparative Example 1)
A heat insulating container of Comparative Example 1 was obtained in the same manner as in Example 1 except that a comparative heat insulating structure without a third heat insulating layer was provided outside the container housing. In addition, in the comparative heat insulation structure, the thickness of the whole heat insulation structure was made the same as Example 1. FIG. Table 1 shows the thicknesses T, t1, and t2 of the comparative heat insulation structure. The average heat transmissivity of this heat insulation container was computed by the said method. Table 1 shows the calculation results of the average heat transmissibility. In addition, since Comparative Example 1 is a reference for evaluation of heat insulation performance and thickness, Table 1 describes both the evaluation result of heat insulation performance and the result of thickness ratio as “1.00”. .

(Example 2)
A heat insulating container of Example 2 was obtained in the same manner as in Example 1 except that the thickness of the first heat insulating layer and the second heat insulating layer was reduced. In addition, this Example 2 was performed in order to evaluate how much the thickness of the whole heat insulation structure can be reduced, in exhibiting the same heat insulation performance as Comparative Example 1. Table 1 shows the thicknesses T, t1, and t2 in the heat insulating structure of Example 2. The average heat transmissivity of this heat insulation container was computed by the said method. Table 1 shows the calculation result of the average heat transmissibility, the evaluation result of the heat insulation performance based on Comparative Example 1, and the thickness ratio based on Comparative Example 1.

（実施例１、２および比較例１の対比）
表１に示すように、実施例１の断熱構造体は、比較例１の断熱構造体と同じ厚さであるにも関わらず、平均熱貫流率が低くなり、断熱性能は２８％向上した。また、実施例２の断熱構造体は、比較例１の断熱構造体と同じ断熱性能であるにも関わらず、全体の厚さを３７％減少させることができた。

(Contrast of Examples 1 and 2 and Comparative Example 1)
As shown in Table 1, although the heat insulating structure of Example 1 had the same thickness as the heat insulating structure of Comparative Example 1, the average heat transmissivity was lowered and the heat insulating performance was improved by 28%. Moreover, although the heat insulation structure of Example 2 was the same heat insulation performance as the heat insulation structure of the comparative example 1, the whole thickness was able to be reduced 37%.

  Thus, according to this invention, the thickness of the 1st heat insulation layer comprised by a foam heat insulation panel and the 2nd heat insulation layer (or integration layer) can be made small significantly. Therefore, if the overall size of the heat insulating container is the same, the heat insulating container of Example 1 or 2 can increase the internal volume of the container housing as compared with the heat insulating container of Comparative Example 1.

(Example 3)
Heat insulation in which the total thickness of the first heat insulating layer and the second heat insulating layer (and the integrated layer) constituted by the foam heat insulating panel is 300 mm, and the thickness of the third heat insulating layer constituted by the vacuum heat insulating material is 100 mm. Assuming the structure, a thermal simulation assuming a temperature gradient from the temperature of LNG (−162 ° C.) to room temperature (25 ° C.) was performed on this heat insulating structure. The result is shown by the alternate long and short dash line I in FIG.

(Comparative Example 2)
A thermal simulation was performed in the same manner as in Example 3 except that a comparative heat insulating structure constituted by a foam heat insulating panel having a total thickness of 400 mm was assumed without providing the third heat insulating layer. The result is shown by a broken line II in FIG.

(Contrast of Example 3 and Comparative Example 2)
As is clear from the simulation results of FIG. 23, in the comparative heat insulation structure of Comparative Example 2, the temperature is proportional to the distance from the inner wall surface of the container housing (that is, the thickness of the heat insulation layer) as indicated by the broken line II. Although it has risen, in the heat insulating structure of Example 3, as shown by the alternate long and short dash line I, the thermal gradient angle of the foam heat insulating panel (first heat insulating layer, second heat insulating layer, and integrated layer) is small, The thermal gradient angle of the vacuum heat insulating material (third heat insulating layer) is large. Therefore, if it is this invention, the atmospheric temperature of the area | region in which the foam heat insulation panel which is an inner side heat insulation layer exists can be reduced with the heat insulation performance of a 3rd heat insulation layer. Moreover, since the heat transfer of the cold temperature of the inner heat insulation layer itself is also reduced (the thermal gradient angle of 0 to 300 mm of the alternate long and short dash line I is gentle), it can be seen that the heat insulation performance of the inner heat insulation layer itself is improved. .

  As described above, according to the present invention, since the heat insulation container that achieves further improvement of heat insulation performance and effectively realizes good heat insulation performance over a long period of time can be obtained, the present invention provides a spherical shape of an LNG transport tanker. It can be widely used in the field of heat insulating containers that hold low-temperature substances such as tanks, LNG tanks installed on land, hydrogen tanks, and the like.

DESCRIPTION OF SYMBOLS 10 Vacuum heat insulating material panel 11 Foamed resin layer 12, 16 Adhesive 13 Fastening member 14, 15 Filling heat insulating material 17 Metal mesh 20A-20C Vacuum heat insulating material 21 Core material 22 Outer packaging material (covering material)
23 Adsorbent 24 Sealing part (sealing fin)
25 Opening 26A, 26B Check valve 27 Sealing part protection layer 30A-30D Foam insulation panel 31, 32 Edge 33 Integrated layer 50 Ground 100 LNG transport tanker 101 Spherical tank 102 Hull 103 Cover 104, 124, 134, 144 Heat insulation container 105, 125, 135, 145 Heat insulation structure 106, 141 Support body 110, 124, 134, 144 Container housing 111 First heat insulation layer 112 Second heat insulation layer 113 Third heat insulation layer 114 Fourth heat insulation layer 120 Above ground Type LNG tank 121 Support structure part 122 Column 123 Brace 130 Underground type LNG tank 131 Concrete structure cheer 132 Roof part 133 Fibrous heat insulating material 140 Hydrogen tank 220 Laminated sheet 220A Outer laminated sheet 220B Inner laminated sheet 221 Surface protective layer 222 Gas barrier layer 223 Thermal welding layer 22 4 Heat-welded surface protective layer 225 Flame-retardant layer 226 Low temperature resistant gas barrier layer 240 Welded part 241 Thin part 242 Thick part 243 Strength reduced part

Claims (19)

Used to hold cryogenic materials stored at temperatures below room temperature,
A container housing;
A heat insulating structure disposed outside the container housing,
The heat insulating structure is a multilayer structure including a first heat insulating layer, a second heat insulating layer, and a third heat insulating layer, which are sequentially provided from the container housing toward the outside.
The third heat insulating layer is provided with a plurality of vacuum heat insulating materials,
Insulated container. The second heat insulating layer has a heat insulating performance equal to or higher than that of the first heat insulating layer,
The heat insulating container according to claim 1. The heat insulation structure includes a portion where the first heat insulation layer and the second heat insulation layer are integrated,
The heat insulating container according to claim 1. The vacuum heat insulating material comprises a fibrous core material and a bag-shaped outer packaging material having gas barrier properties, and the core material is enclosed in a vacuum sealed state inside the outer packaging material,
Among the outer packaging materials, the inner outer packaging material constituting the inner surface facing the container housing is configured to have higher low-temperature resistance than the outer outer packaging material constituting the outer surface. Item 2. The insulated container according to Item 1. The vacuum heat insulating material has a fin-like sealing portion that is sealed by bonding the outer packaging materials around each other,
The third heat insulating layer is configured by disposing the vacuum heat insulating material on the outside of the second heat insulating layer in a state where the sealing portion is folded on the container housing side.
The heat insulation container according to claim 4. The plurality of vacuum heat insulating materials provided in the third heat insulating layer are arranged adjacent to each other in a state in which their end faces are butted together,
The heat insulating container according to claim 1. Of the third heat insulating layer, the portion where the end faces of the vacuum heat insulating material are butted together is filled with a filling heat insulating material different from the vacuum heat insulating material,
The heat insulating container according to claim 6. The first heat insulation layer and the second heat insulation layer include a plurality of heat insulation panels, and the heat insulation panels are arranged adjacent to each other in a state in which their end faces are butted together.
Furthermore, when the portion where the end surfaces of the heat insulating panel are butted together, or the portion where the end surfaces of the vacuum heat insulating material are butted together is a butting portion,
The positions of the butted portions of at least two heat insulating layers among the first heat insulating layer, the second heat insulating layer, and the third heat insulating layer are shifted from each other,
The heat insulating container according to claim 1. The vacuum heat insulating material is mechanically fixed to the first heat insulating layer or the second heat insulating layer in a state where the entire inner surface facing the container housing is not bonded to the outer surface of the second heat insulating layer. It is characterized by
The heat insulating container according to claim 1. The adjacent vacuum heat insulating materials are arranged so that the distance from the container housing is equal,
The heat insulating container according to claim 1. The vacuum heat insulating material comprises a fibrous core material and a bag-shaped outer packaging material having gas barrier properties, and the core material is enclosed in a vacuum sealed state inside the outer packaging material,
It has an explosion-proof structure that suppresses or prevents sudden deformation of the vacuum heat insulating material,
The heat insulating container according to claim 1. The vacuum heat insulating material is configured as a heat insulating panel in which the outer packaging material is completely covered with a foamed resin layer,
The explosion-proof structure is realized by forming the foamed resin layer so that no organic foaming agent remains after foaming,
The heat insulating container according to claim 11. The vacuum heat insulating material is further enclosed with the core material inside the outer packaging material, and further includes an adsorbent that adsorbs residual gas inside,
The explosion-proof structure is a chemisorption type in which the adsorbent chemically adsorbs the residual gas, is non-exothermic that does not generate heat due to adsorption of the residual gas, or is a chemisorption type and non-exothermic. It is realized by
The heat insulating container according to claim 11. The explosion-proof structure is realized by providing the outer packaging material with an expansion relaxation portion that releases the residual gas to the outside and relaxes the expansion when the residual gas expands inside the outer packaging material. Features
The heat insulating container according to claim 11. The expansion relaxation portion is a check valve provided in the outer packaging material, or a portion provided in advance in the outer packaging material, which is partially low in strength.
The heat insulation container according to claim 14. The outer packaging material has an opening for decompressing the inside of the bag,
The opening has a heat welding layer on its inner surface, and the inside of the bag can be sealed by heat welding in a state where the heat welding layers are in contact with each other.
The sealing portion formed by thermal welding of the opening includes a plurality of thin portions where the thickness of the welded portion between the thermal welding layers is small.
The heat insulation container according to claim 14. The outer packaging material is composed of two laminated sheets,
One side of the laminated sheet is the heat welding layer,
In a state where the two heat-bonding layers of the laminated sheet are opposed to each other, a part of the peripheral part of the laminated sheet is used as the opening, and the remaining part of the peripheral part excluding the opening is surrounded. It is formed into a bag shape by heat welding to
The heat-welded part in the peripheral part is the sealing part including a plurality of the thin parts,
The heat insulating container according to claim 16. In addition to the plurality of thin portions, the sealing portion includes a plurality of thick portions having a large thickness of the welded portion,
The thick part and the thin part are alternately arranged so that the thin part is located between the thick parts,
The heat insulating container according to claim 16. The container housing has a shape including a curved surface,
The heat insulating container according to claim 1.

Images