JP2007085696A - Vacuum heat insulating box body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve reliability and heat insulating performance by suppressing deformation, cracking and distortion of a box body in a vacuum heat insulating box body of double wall structure. <P>SOLUTION: The vacuum heat insulating box body 1 has a vacuum heat insulating structure by having the box body consisting of an outer box 3 and an inner box 5 formed of at least a gas-barrier material, providing a heat insulating space 7 between the outer box 3 and inner box 5 with a core material 6 abutting on the box body, and reducing the pressure of the heat insulating space 7. The volume change before and after pressure reduction of the core material 6 following the deformation of the box body by atmospheric compression caused by pressure reduction is within 50%. Consequently, even if the box body is compressed by atmospheric compression caused by pressure reduction, the volume change of the core material 6 is small. The deformation of the box body can thereby be suppressed, and reliability such as suppression of deformation and cracking can be improved. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vacuum heat insulation box that can be used as a vacuum heat insulator for a refrigerator, a heat insulation container, a vending machine, an electric water heater, a vehicle house, or the like that requires heat insulation.

  In recent years, energy saving is desired because of the importance of preventing global warming, which is a global environmental problem, and energy saving is also promoted for consumer devices. In refrigerators, etc., heat entry is cut off and the operating rate of the refrigeration system is lowered, contributing to energy saving. In the heat-reserving liquid storage container that is built into the circulation system of an automobile engine, the heated and cooled water is kept warm and effectively used. By doing so, the combustion efficiency from the initial stage of engine operation can be secured. From the above viewpoint, the heat insulation performance improvement of the heat insulation box is calculated | required.

  In the case where heat conduction is performed through the presence of air, there is a mean free path of gas as a physical property affecting the heat insulation performance. The mean free path of a gas is the distance traveled until one of the molecules that make up the air collides with another molecule. If the void formed is larger than the mean free path, the molecules in the gap Collide and heat conduction by gas occurs, so that the thermal conductivity increases.

  The heat insulation principle of a vacuum heat insulator is to eliminate as much air as possible to transfer heat and reduce heat conduction by gas. On the other hand, when the void is smaller than the mean free path, the thermal conductivity is small. This is because there is almost no heat conduction due to air collision.

  As a means for solving such a problem, there is a vacuum heat insulating body constituted by a core material that holds a space and a jacket material that blocks the space and outside air. In general, powder materials, fiber materials, continuous foams, etc. are used as the core material, but in recent years, the demand for vacuum insulators has been diversified, and higher performance vacuum insulators. Is required.

  For example, a vacuum insulation panel manufacturing method, which is one of the vacuum insulation materials, covers a core material with a continuous structure such as rigid urethane foam made of open cells with a gas barrier metal-plastic laminate film, etc. After exhausting, it is packed into a panel (see Patent Document 1). When this is used for a heat-insulating box such as a refrigerator, it has a double structure in which it is attached to the inner surface of the box container material and foamed with urethane foam.

  In addition, a reservoir tank that is built into the circulation system of an automobile engine and keeps cooling water uses a metal vacuum double container as a heat insulating structure, and the cooling water is heated while being circulated as the engine operates. Is introduced into the main body of the heat insulating container through the partition wall, and after the engine stops, the temperature rising cooling water stagnating in the container is kept warm, and at the next engine start, the temperature rising cooling water is supplied to ensure combustion efficiency (patent) Reference 2).

  In the heat insulation structure of the vacuum double container made of metal, the degree of vacuum at the industrial level is about 10 Pa, but there is no solid conduction, and since it is made of metal, there is almost no intrusion of outside air. Further, since it is used at a low temperature of 100 ° C. or less, there is almost no influence of radiation.

  In addition, in the heat insulation structure of the resin vacuum double container used for heat insulation such as tableware and cups for weight reduction, in order to improve the gas barrier property, the surface in contact with the internal space is electroplated, electroless plated, or vapor deposited. A metal film is formed. In addition, blow molding or injection molding is performed to obtain a degree of freedom in shape, and plating is performed after welding the inner box and the outer box (see Patent Document 3).

In addition, in order to ensure heat insulation performance at a low degree of vacuum, the heat insulation space is filled with a heat insulating material such as fine particulate silica, and in order to increase the mechanical strength of the container, a support is provided between the inner container and the outer container. The provided vacuum heat insulation container is also proposed (refer to patent documents 4).
JP-A-7-293785 JP-A-10-71840 JP-A-6-113963 Japanese Patent Laid-Open No. 2001-128860

  In the structure using the vacuum heat insulation panel of patent document 1, there exists a problem which cannot cover the heat insulation box whole surface with a vacuum heat insulation panel, and there exists a limit in heat insulation performance. Moreover, there exists a problem in which a shape will be limited in a vacuum heat insulation panel. When molded and processed on a vacuum insulation panel, the metal foil is a material that is difficult to extend compared to the resin material, so when pulled by the process, cracks and holes occur in the metal foil, the degree of vacuum decreases, and the heat insulation performance decreases. To do. Further, depending on the core material, a stress may be applied to the core material to damage the outer skin material to cause a pinhole, resulting in a phenomenon that the degree of vacuum is lowered.

  Furthermore, by using a plurality of vacuum heat insulating panels, it is possible to form a cube or the like, but it is difficult to form curved surfaces and irregularities. In addition, it is possible to improve the atypicality by using a small vacuum insulation panel, but it requires a lot of man-hours and becomes complicated, and there is no insulation between the vacuum insulation panel and the vacuum insulation panel, so that the insulation performance Is inferior, and by using a large number of sheets, the area increases and the heat insulation performance decreases.

  Moreover, in the structure of patent document 2, since it is comprised with the metal, there exists a problem that the heat leak through a metal material is large and the weight also becomes heavy. Moreover, since the moldability is inferior to that of resin, the degree of freedom in shape is low. In addition, when the plate thickness is reduced in order to reduce the weight, the strength is reduced, so that there is a problem that the shape is limited to a shape capable of maintaining the strength, such as a cylindrical shape.

  Moreover, in the structure of patent document 3, although there is no problem in a moldability, a weight, and gas barrier property, since a vapor deposition film is formed after shaping | molding, a man-hour increases and productivity worsens. In addition, in the case of a complicated shape, there is a portion where the vapor deposition film cannot be formed, and thus there is a limitation on the shape.

  Also in electrolytic plating, since resin does not have electrical conductivity, it is necessary to impart conductivity, which increases the number of steps and productivity is also poor. In electroless plating, the number of processes increases and there is a problem of using an environmentally hazardous substance such as formaldehyde as a reducing agent.

  Furthermore, since both the electrolytic plating method and the electroless plating method are performed in a liquid, cleaning and drying processes are required after the plating film is produced. If the drying is insufficient, the degree of vacuum deteriorates and the heat insulation performance deteriorates. Furthermore, the resin material has a lower strength than the metal material, and when the pressure is reduced, there is a problem that a compressive force is applied by the atmosphere, and the resin material is cracked or deformed.

  There is also a method of enclosing an inert low thermal conductive gas such as Xe inside, but the thermal conductivity of the gas is increased and the heat insulation performance is inferior compared to vacuum. Also, by increasing the thickness of the resin material, the strength can be improved, but since the thickness increases, the amount of heat leak increases, the material cost is high, and the space of the wall material increases, Volumetric efficiency becomes worse.

  Moreover, in the structure of patent document 4, although the intensity | strength is reinforced with the support body, a support body part does not have heat insulation, and heat leakage increases through a support body and heat insulation performance falls, so that there are many support bodies. Further, if the number of supports is small, the strength of the portion without the support decreases, distortion occurs, and if the state continues for a long time, cracks and breakage occur in the worst case. On the other hand, when the skin material is thickened, the thickness increases, so the amount of heat leak increases, the material cost increases, and the space of the wall material increases, resulting in poor volumetric efficiency.

  An object of the present invention is a vacuum heat insulation box having high heat insulation performance, having sufficient gas barrier properties, high atypical properties, and high reliability in gas barrier properties, strength, and heat insulation performance against atmospheric compression. And it is providing the vacuum heat insulation box which was lightweight and excellent in volumetric efficiency.

  In order to achieve the above object, the vacuum heat insulating box of the present invention is a core material that is vacuum-sealed in a space constituted by at least an outer box and an inner box made of a gas barrier material, and the outer box and the inner box. A vacuum heat insulation box having a vacuum heat insulation structure comprising: a volume change rate of the core material before and after decompression is 50% or less.

  The volume change rate of the core material is, for example, that the core material volume reduced by compressing to the atmosphere by enclosing the core material in a bag having high gas barrier properties such as a laminated film bag and reducing the pressure to the core material volume before the pressure reduction It is the rate of change of the core material volume that is reduced.

  Since the volume change rate of the core material is within 50%, even if the box is compressed by atmospheric compression due to reduced pressure, the volume change of the core material is small, so that deformation of the box can also be suppressed, and deformation and cracks can be suppressed. Such reliability can be improved. In particular, if the material constituting the box is thin and the strength is weak, the effect is high, and the box material can be made thin, so that the volumetric efficiency is also improved.

  On the other hand, if the volume change rate of the core material is larger than 50%, the deformation of the box body also increases, the appearance is remarkably impaired, and cracks, dents, distortion, etc. occur in the outer box and inner box, and the outside air flows in. And the heat insulation effect is lost. Deterioration of cracks and the like is not limited to those occurring at the time of decompression, but also includes the phenomenon that deformation and cracks occur due to stress applied for a long period of time.

  The vacuum heat insulating box of the present invention is characterized in that the core material has a three-dimensional shape formed into the shape of the space. For example, in the case of pouring into a space such as a powder material, if the space has a complicated shape, unevenness in the unfilled portion and the filling density may occur, and the heat insulation performance and the volume change rate may vary. However, since the core material has a three-dimensional shape, the non-filled portion and filling density unevenness can be eliminated, and the core material can be filled with high dimensional accuracy, and has uniform heat insulation performance and volume change rate. Can do.

  In addition, even for core materials that are difficult to fill after box molding, such as inorganic fiber materials, it is possible to sandwich the core material between the outer box and the inner box by simplifying the construction method. Can be achieved.

  The vacuum heat insulating box of the present invention is characterized in that the gas barrier material is a multilayered resin material and metal foil.

  As a result, the gas barrier property of the resin material can be remarkably enhanced, and it is possible to use a simple method such as insert molding or in-mold molding without increasing the load on facilities and processes, such as vapor deposition and plating. Multi-layering is possible. In addition, the resin barrier alone may cause the gas barrier properties to decrease as the temperature increases.On the other hand, the heat leak increases and the heat insulation performance decreases with the metal material alone. In addition to improving gas barrier properties, heat leak can also be reduced and applied.

  The vacuum heat insulation box of the present invention has a volume change rate before and after decompression of the core material sealed under reduced pressure in a space constituted by the outer box and the inner box within 50%. Even if is compressed, since the volume change of the core material is small, deformation of the box can be suppressed, and reliability such as deformation and crack suppression can be improved. In particular, if the material constituting the box is thin and the strength is weak, the effect is high, and the box material can be made thin, so that the volumetric efficiency is also improved.

  In addition, the vacuum heat insulating box of the present invention eliminates unevenness of the unfilled portion and filling density because the core material has a three-dimensional shape, and can further fill the core material with high dimensional accuracy. It can have thermal insulation performance and volume change rate.

  Further, the vacuum heat insulating box of the present invention is characterized in that the gas barrier material is a multilayered resin material and metal foil, and can significantly improve the gas barrier property of the resin material. In addition, it is possible to form a multilayer by a simple technique such as insert molding or in-mold molding without increasing the load of facilities and processes as in the vapor deposition method and the plating method.

  In addition, the resin barrier alone may cause the gas barrier properties to decrease as the temperature increases.On the other hand, the heat leak increases and the heat insulation performance decreases with the metal material alone. In addition to improving gas barrier properties, heat leak can also be reduced and applied.

  The invention of the vacuum heat insulation box according to claim 1 of the present invention is a core material that is vacuum-sealed in a space constituted by at least an outer box and an inner box made of a gas barrier material, and the outer box and the inner box. A vacuum heat insulation box having a vacuum heat insulation structure comprising: a volume change rate of the core material before and after decompression is 50% or less.

  The volume change rate of the core material is, for example, that the core material volume reduced by compressing to the atmosphere by enclosing the core material in a bag having high gas barrier properties such as a laminated film bag and reducing the pressure to the core material volume before the pressure reduction It is the rate of change of the core material volume that is reduced.

  Since the volume change rate is within 50%, even if the box is compressed by atmospheric compression due to reduced pressure, the volume change of the core material is small, so that deformation of the box can be suppressed, and reliability such as suppression of deformation and cracks can be suppressed. Can be improved. In particular, if the material constituting the box is thin and the strength is weak, the effect is high, and the box material can be made thin, so that the volumetric efficiency is also improved.

  In addition, the smaller the volume deformation rate, the thinner the outer box and inner box can be made, and even materials with inferior extensibility and strength can be used, resulting in space saving and material reduction effects. In order to maintain long-term reliability, the volume change rate is preferably within 20%.

  In order to prevent surface deformation almost completely and make the appearance more beautiful, the volume change rate is more preferably 5% or less.

  On the other hand, when the volume change rate is greater than 50% and the deformation of the box increases, the appearance is remarkably impaired, and cracks, dents, distortion, etc. occur in the outer box and the inner box, and the outside air flows in, thereby providing a heat insulation effect. Is lost. Deterioration of cracks and the like is not limited to those occurring at the time of decompression, but also includes the phenomenon that deformation and cracks occur due to stress applied for a long period of time.

  The core material is not particularly limited as to the material system, and is not particularly limited to organic or inorganic fibers, powdered solids, foamed resins, and the like.

  For example, in the case of a core material using fibers, inorganic fibers such as glass wool, glass fibers, alumina fibers, silica alumina fibers, silica fibers, rock wool, silicon carbide fibers, natural fibers such as cotton, synthetic fibers such as polyester and nylon, etc. Known materials such as organic fibers can be used.

Further, in order to achieve higher performance heat insulation performance with a fibrous core material, the core material is made of inorganic fibers having an average fiber diameter of 0.1 μm or more and 10 μm or less, and the density of the core material is 100 kg / m ³ or more. It is desirable that it is 400 kg / m ³ or less. Further, the inorganic fiber is preferably glass wool.

  By making the core material into a fibrous shape, the core materials are in point contact with each other, and the contact area is reduced, so that the solid thermal conductivity transmitted through the core material is reduced. In addition, it is desirable to dry the core material sufficiently to remove the adsorbed gas such as moisture, but the organic fiber is more likely to generate adsorbed gas such as moisture than the inorganic fiber. In some cases, decomposition gas is also generated, so that the heat insulation performance is lowered.

  Moreover, if the average fiber diameter of the core fiber is less than 0.1 μm, industrial production is difficult and practically unsuitable. Furthermore, if it is larger than 10 μm, the gap between the fibers becomes large, and a vacuum heat insulating box with excellent initial performance cannot be obtained.

Further, by reducing the gap diameter between fibers by setting the density to 100 kg / m ³ or more and 400 kg / m ³ or less, a core material that retains the optimum gap diameter from the viewpoint of initial performance and reliability with respect to the fiber diameter. It is possible to obtain a vacuum heat insulation box that is excellent in heat insulation performance and ensures long-term reliability.

  On the other hand, in the core material using powder, known materials such as inorganic powder such as silica, pearlite, carbon black, or organic powder such as synthetic resin powder are solidified with a fiber binder or an inorganic or organic liquid binder. Can be used.

  Moreover, well-known materials, such as a urethane foam, a phenol foam, a styrene foam, can be used for foamed resin.

Moreover, in order to give a higher performance heat insulation performance with a powdery core material, a dry silica having an average primary particle diameter of 100 μm or less and an inorganic fiber material having an average fiber diameter of 10 μm or less are mixed with 5 to 20 wt%. The density formed by pressure molding is 100 kg / m ³ or more and 400 kg / m ³ or less.

  By using a dry silica having an average primary particle diameter of 100 nm or less and an inorganic fiber material having an average fiber diameter of 10 μm or less, it is possible to solidify the dry silica, and further have excellent vacuum heat insulating properties, a high gas phase rate, and a volume. The volume change rate of dry silica with a large change rate is reduced, and the particle size of dry silica is as small as 100 nm or less, so the gap distance between particles is small, the influence of gas heat conduction is small, and high heat insulation performance The vacuum heat insulating material which has can be obtained.

  Factors for solidification are powders with small particle diameters, so intermolecular force works and the powders adhere to each other, or because they are dry, the surface functional groups are few and the mutual repulsion is less, so the powders are easy to adhere, or Silica and inorganic fibers have a good affinity, so they easily adhere to each other, and since the inorganic fiber has a small fiber diameter, the specific surface area increases, that is, the surface energy increases, making it easier to bind to the powder, or their interaction. It is conceivable that

  Further, by using dry silica having a very fine particle diameter and an inorganic fiber material having a small fiber diameter, a molded body having almost no dust can be obtained.

  This is because, as described above, the intermolecular force between powders with small particle diameters, adhesion between powders due to a small number of surface functional groups, good affinity between silica and inorganic fibers, large surface energy of fine fiber materials, etc. Can be considered.

  Moreover, since it has elasticity with a strong molded object by the said combination, the molded object which also has flexibility can be obtained.

  The reason for this is considered to be that, since fibers having an average fiber diameter of 10 μm or less are used, flexural elasticity is improved and flexibility can be obtained.

In addition, the density between 50 kg / m ^{3 and} 400 kg / m ³ can be used to reduce the void diameter between particles, and to obtain a core material that retains the optimum void diameter from the viewpoint of initial performance and reliability, A vacuum heat insulating box body having excellent heat insulating performance and ensuring long-term reliability can be produced.

  Moreover, heat insulation performance improves further by mixing carbon black 4.5-16 wt% with respect to the said dry-type silica. By using such a core material obtained by mixing a powdery carbon material in dry silica for a vacuum heat insulation box, the heat insulation performance is remarkably improved.

  For example, carbon black and titanium oxide, which are added to silica to improve heat insulation performance, are known to work as radiation inhibitors at high temperatures. It is done.

  Although this reason is not certain, it is considered that solid heat conduction is reduced by some action of silica powder and carbon black.

  The invention of the vacuum heat insulation box according to claim 2 is characterized in that the core material in the invention according to claim 1 has a three-dimensional shape.

  For example, when injecting into a space such as a powder material, if the space has a complicated shape, unevenness occurs in the unfilled portion and packing density, resulting in uneven performance and volume change rate, and heat insulation performance and volume change rate. There is a risk of variation. However, since the core material has a three-dimensional shape, the non-filled portion and filling density unevenness can be eliminated, and the core material can be filled with high dimensional accuracy, and has uniform heat insulation performance and volume change rate. Can do.

  In addition, even for core materials that are difficult to fill after box molding, such as inorganic fiber materials, it is possible to sandwich the core material between the outer box and the inner box by simplifying the construction method. Can be achieved.

  The invention of the vacuum heat insulation box according to claim 3 is characterized in that the three-dimensional core material in the invention according to claim 2 is divided into at least two.

  By dividing the three-dimensional core material into two or more, even if it has a complicated shape and is difficult to form once, it can be easily produced.

  Further, in a material having thermal conductivity anisotropy such as a fiber material, it is important to align the core material direction in a direction in which the heat insulation performance is improved.

  According to a fourth aspect of the present invention, the gas barrier material according to any one of the first to third aspects is obtained by multilayering a resin material and a metal foil. It is characterized by this.

  Metal foil has a higher gas barrier property than a resin material having a high gas barrier property, and can greatly increase the gas barrier property of the resin material, as well as increase the load on equipment and processes, such as vapor deposition and plating. However, it is possible to easily form multiple layers at the time of molding like insert molding. Furthermore, by using the foil, it is possible to minimize heat leakage due to the wraparound of the outer box and the inner box.

  In addition, the gas barrier property becomes better as the area of the multilayer with the metal foil increases. Further, the metal foil is less dependent on temperature and humidity, and can have better gas barrier properties against environmental changes. Further, the metal foil does not need to be a single metal, and a multilayer film with a resin material such as a laminate film may be used in order to improve adhesion and handling. Moreover, even if it is the vapor deposition film which vapor-deposited the metal on the resin material, since the same effect is acquired, there is no problem.

  Moreover, you may provide the surface protective layer for prevention of a pinhole etc. on the surface of metal foil and a metal vapor deposition film as a multilayer film. As the surface protective layer, a polyethylene terephthalate film, a stretched product of polypropylene film or the like can be used, and if a nylon film or the like is further provided on the outer side, flexibility is improved.

  In addition, if the metal becomes too thick, heat leaks through the metal foil, so 1 mm or less is desirable. Further, if it is too thin, it may be broken at the time of molding, and pinholes are also easily formed.

  The metal foil may be made of any material such as aluminum, stainless steel, iron and copper, but aluminum foil is most desirable from the viewpoint of workability and cost.

  In addition, it is preferable to cover the entire surface of the metal foil. For example, the metal foil is not wrinkled and is not easily damaged, and a corner portion or the like is not covered. . Therefore, by forming a multilayer with the gas barrier material, it is possible to reinforce the gas barrier property of the portion that cannot be covered with the metal foil and maintain the heat insulating property of the vacuum heat insulating box for a long period of time.

  In addition, metal foil is usually placed on the mold side and insert molding or in-mold molding is performed. If a three-dimensional core material using a material with a small volume reduction rate is used, the metal foil is attached to the core material side. It becomes possible to install, and the degree of freedom of molding of the resin material is remarkably improved. Furthermore, since the volume reduction rate of the core material is as small as 50% or less, even if the box and the core material are deformed by atmospheric compression, the portion where the metal foil is damaged is remarkably small, and the gas barrier property can be secured.

  In addition, a film obtained by vapor-depositing a metal material on a resin material has a low degree of crystallinity unlike metal foil, and thus can be easily stretched and a better multilayer material can be formed. Further, a gas barrier property may be improved by forming a vapor deposition film of an inorganic oxide such as silica or alumina on the resin material.

  According to a fifth aspect of the present invention, the resin material in the fourth aspect of the invention is an ethylene-vinyl alcohol copolymer, polyacrylonitrile, polyamide 6, polyamide 11, polyamide 12, polybutylene terephthalate. , Polybutylene naphthalate, polyethylene naphthalate, polyvinylidene fluoride, polyvinylidene chloride, ethylene-tetrafluoroethylene copolymer, polytetrafluoroethylene, polyphenylene fluoride, polyether ether ketone, polyimide It is characterized by using.

  The gas barrier material can form a vacuum heat insulating box having particularly high gas barrier properties and higher reliability.

  Furthermore, it becomes possible to reduce the multilayered portion with the metal foil, for example, it is possible to maintain an equivalent gas barrier property even in a vacuum heat insulating box with a complicated shape that is difficult to multilayer the metal foil, Freedom formation can be improved.

  Further, even if the thickness of the resin material is reduced, it is possible to have the same gas barrier property, and space saving can be achieved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is an external perspective view of the vacuum heat insulation box according to the first embodiment of the present invention, and FIG. 2 is an exploded perspective view of the vacuum heat insulation box according to the first embodiment. FIG. 3 is a longitudinal sectional view of the vacuum heat insulation box in the first embodiment.

  As shown in FIG. 1, a vacuum heat insulation box 1 having a hot water storage structure in which hot water or water can be stored inside has an inlet 2 for storing water or the like inside, and an outer outer box 3. Is made of a gas barrier material and has an exhaust port 4 for depressurizing the heat insulation space.

  As shown in FIG. 2, the inner box 5 made of a gas barrier material having an inlet 2 has a three-dimensional shape and is divided into a core material 6, and the outer box 3 and the outer box 3 which are further divided on the outer side. It is comprised from the exhaust port 4 which exhausts air.

The gas barrier material has an air permeation rate of 100 [cm ³ · 10 μm / m ² · day · atm] or less, and preferably 0.5 [cm ³ · 10 μm / m ² · day · atm] or less. desirable.

When the air permeation speed is greater than 100 [cm ³ · 10 μm / m ² · day · atm], the amount of air permeation from the outside increases and the long-term reliability is poor. Moreover, even if it respond | corresponds with the air adsorption | suction by an adsorbent, the required amount of an adsorbent increases, the solid thermal conductivity of an adsorbent increases, and heat insulation performance falls.

  Also, the molding method is not limited, but blow molding, injection molding, vacuum molding, and pressure molding are most easily molded, and any molding method may be used. Moreover, you may combine these shaping | molding methods.

  The outer box 3 is cut in half when integrally molded, and is used as it is when divided and molded. Solidified into the same three-dimensional shape as the space between the inner box 5 and the outer box 3, and further divided core material 6 and the inner box 5 are inserted into the inside, and the neck of the inlet 2 of the outer box 3 and the inner box 5. Each part is welded. Thereafter, the outer box 3 cut in half is welded at the cut portion and sealed, and then the pressure is reduced from the exhaust port 4 to produce a vacuum heat insulating box.

  In order to insert the core material 6 into the inner box 5, it is easier to insert the core material 6 into two or more parts. Further, the more complicated the shape is, the easier it is to form the box by dividing and inserting it. If the joint between the core material and the core material is in close contact, the heat insulation performance and the strength of the box body are not greatly affected.

  The outer box 3 may be welded by welding the end surfaces. However, if the flange portion is formed in advance, the outer box 3 can be welded easily.

  The welding method is not particularly limited, but vibration welding, ultrasonic welding, laser welding, IRAM, DSI, welding, hot melt, electromagnetic induction, hot air welding, impulse welding, hot air welding, near red welding, diffusion bonding Etc. are used. These may be combined.

  As shown in FIG. 3, the vacuum heat insulating box 1 is composed of an outer box 3 and an inner box 5 at an upper portion, and a heat insulating space 7 exists between the outer box 3 and the inner box 5. The inside of the heat insulation space is filled with the core material 6 and has a gas adsorbent 8 and a moisture adsorbent 9.

  The heat insulating space 7 is exhausted from the exhaust port 4 to become a decompressed space, and then sealed by sealing the exhaust port 4.

  The gas adsorbing material adsorbs the gas entering from the material constituting the box, the adsorbing gas remaining inside, etc., and can ensure long-term reliability.

  As the gas adsorbent, oxygen, nitrogen, water, carbon dioxide, and hydrogen adsorbents can be used alone or in combination.

  The core material 6 has a volume reduction rate of 50% or less indicating the ratio of the volume before decompression due to atmospheric compression under reduced pressure, and the vacuum heat insulating box 1 is made of the core material even if the heat insulating space 7 is decompressed. Since it does not deform beyond volume reduction, the load on the inner and outer box materials is reduced, so that cracks, cracks and deformation due to atmospheric compression are unlikely to occur, and a vacuum heat insulating box with high box strength and high reliability Can be configured.

  In particular, when the inner box and outer box materials have lower rigidity than atmospheric compression, or when the material thickness is thin, the effect is great. In addition, fatigue failure occurs due to stress applied over the long term, and the inner box and outer box materials deteriorate due to the external environment and the rigidity decreases, causing cracks and cracks. If it is 50% or less, it will not be deformed more than the volume reduction of the core material.

  Further, the smaller the volume reduction rate, the higher the effect and the better the dimensional accuracy and the appearance of the appearance. Therefore, it is preferably 10% or less, and 3% or less is desirable in order to obtain more accurate dimensional accuracy.

  If the volume reduction rate is greater than 50%, the appearance and dimensional accuracy are also greatly reduced. Further, the load and deformation rate of atmospheric compression on the inner box and outer box materials are increased, and the inner box and outer box materials are easily cracked or cracked in the short or long term. It is possible to increase the strength by increasing the thickness of the inner box and outer box materials, but the volume efficiency is reduced and the cost is increased. Furthermore, since the cross-sectional areas of the inner box and outer box materials increase, the amount of heat that flows from the inner box and outer box materials increases, and the heat insulation performance also decreases.

Example 1
The inner box is a multilayer material made of polypropylene having a thickness of 1 mm and an ethylene-vinyl alcohol copolymer (hereinafter referred to as EVOH) having a thickness of 100 μm. The polypropylene is on the inside, and molding is performed by blow molding. Polypropylene and EVOH are bonded with a bonding material (10 μm).

  The outer box is a multi-layer material consisting of high density polyethylene with a thickness of 1 mm and EVOH with a thickness of 100 μm. The high density polyethylene is on the outside. Like the inner box, the outer box is made by blow molding. 10 μm).

The outer box formed by blow molding is cut in half, and a core material solidified into the same three-dimensional shape as the space between the inner box and the outer box is inserted. The core material is prepared by press-molding glass fibers having an average fiber diameter of 5 μm at 500 ° C., adjusting the density to 250 kg / m ³ , and dividing the glass fiber into two parts.

  Then, the inner box is inserted inside, and further a gas adsorbent and a moisture adsorbent are inserted. Zeolite was used as the gas adsorbent, and calcium oxide was used as the water adsorbent. The outer box and the inner box are welded at the neck portion of the injection port, and the outer box cut in half is welded at the cut portion, sealed, and then depressurized from the exhaust port to produce a vacuum heat insulation box.

  As a result of measuring the volume of the core material produced under the same conditions as the inserted core material, and then measuring the volume after depressurization, the volume reduction rate was 3.3%. The produced vacuum heat insulation box body was better than Comparative Example 1 without any noticeable change in appearance. Further, the thermal conductivity is 0.0035 W / mK, which is higher than that of Comparative Example 1 and has high heat insulation performance.

  Moreover, although it was left to stand at 40 degreeC for three months, the change of an external appearance and a performance was not seen compared with the comparative example 1 too.

(Example 2)
The inner box is a multilayer material composed of an ABS resin having a thickness of 0.3 mm and an ethylene-vinyl alcohol copolymer (hereinafter referred to as EVOH) having a thickness of 100 μm, with polypropylene on the inside, and molding is performed by blow molding. Further, the ABS resin and EVOH are bonded with a bonding material (10 μm).

  The outer box is a multilayer material consisting of high density polyethylene with a thickness of 1 mm and EVOH with a thickness of 100 μm. The high density polyethylene is on the outside and is produced by double injection molding. The high density polyethylene has a bonding material with EVOH. It is mixed. When molding by injection molding, the core material is molded in half and solidified into the same three-dimensional shape as the space between the inner box and the outer box. In addition, a flange portion is provided to facilitate the joining.

For the core material, 10 wt% carbon black and 10 wt% glass fiber with an average fiber diameter of 5 μm are mixed with dry silica and dry silica with an average primary particle diameter of 80 μm, and press-molded into a space shape, The density was solidified to 260 kg / m ³ . Also, it is molded in half and inserted in advance so that it can be inserted.

  Then, the inner box is inserted inside, and further a gas adsorbent and a moisture adsorbent are inserted. Zeolite was used as the gas adsorbent, and calcium oxide was used as the water adsorbent. The outer box and the inner box are welded at the neck portion of the injection port, and the outer box cut in half is welded at the cut portion, sealed, and then depressurized from the exhaust port to produce a vacuum heat insulation box.

  As a result of measuring the volume of the core material produced under the same conditions as the inserted core material, and then measuring the volume after depressurization, the volume reduction rate was 8.5%. The produced vacuum heat insulation box body was better than Comparative Example 1 without any noticeable change in appearance. In addition, the thermal conductivity is 0.0055 W / mK, which is higher than that of Comparative Example 1.

  Moreover, although it was left to stand at 40 degreeC for 3 months, the change of an external appearance and a performance was not seen compared with the comparative example 1 too.

(Example 3)
The inner box is a multilayer material composed of an ABS resin having a thickness of 0.3 mm and an ethylene-vinyl alcohol copolymer (hereinafter referred to as EVOH) having a thickness of 100 μm. The ABS resin is on the inside, and molding is performed by blow molding. Further, the ABS resin and EVOH are bonded with a bonding material (10 μm).

  The outer box is a multilayer material consisting of high density polyethylene with a thickness of 1 mm and EVOH with a thickness of 100 μm. The high density polyethylene is on the outside and is produced by double injection molding. The high density polyethylene has a bonding material with EVOH. It is mixed. When molding by injection molding, mold in half and insert the inner box. In addition, a flange portion is provided to facilitate the joining.

  Then, the inner box is inserted inside, and further a gas adsorbent and a moisture adsorbent are inserted. Zeolite was used as the gas adsorbent, and calcium oxide was used as the water adsorbent. The outer box and inner box are welded at the neck portion of the inlet, and the outer box cut in half is welded at the cut portion and sealed. Thereafter, a powdery core material is sealed from the exhaust port.

The core material used was a mixture of dry silica having an average primary particle size of 80 μm and dry silica and 10 wt% carbon black. From the space volume and the amount enclosed, the density was 90 kg / m ³ . Thereafter, the pressure is reduced from the exhaust port to produce a vacuum heat insulation box.

  The inserted core material was put into a laminate film, the volume after decompression was measured, and the volume before decompression was determined from the encapsulated density and calculated. As a result, the volume reduction rate was 24.5%. This is presumably because the core material was not fully encapsulated because the powder having a high gas phase rate was encapsulated from the narrow mouth. The produced vacuum heat insulation box was better than Comparative Example 1 although some dents were observed. In addition, the thermal conductivity is 0.0065 W / mK, which is higher than that of Comparative Example 1.

  Moreover, although it was left to stand at 40 degreeC for 3 months, a deformation | transformation expanded and the change of performance was not seen, but it was favorable compared with the comparative example 1.

Example 4
The inner box is a multilayer material made of polypropylene having a thickness of 1 mm and an ethylene-vinyl alcohol copolymer (hereinafter referred to as EVOH) having a thickness of 100 μm. The polypropylene is on the inside, and molding is performed by blow molding. Polypropylene and EVOH are bonded with a bonding material (10 μm).

  The outer box is a multi-layer material consisting of high density polyethylene with a thickness of 1 mm and EVOH with a thickness of 100 μm. The high density polyethylene is on the outside. Like the inner box, the outer box is made by blow molding. 10 μm). The outer box formed by blow molding is cut in half, and a core material solidified into the same three-dimensional shape as the space between the inner box and the outer box is inserted.

The core material was prepared by applying a water glass aqueous solution as a binder to glass fibers having an average fiber diameter of 5 μm, drying, press molding at 500 ° C., and adjusting the density to 270 kg / m ³ . Water glass is 3 wt% by weight. Moreover, it divided into two and shape | molded so that it might be easy to insert.

  Then, the inner box is inserted inside, and further a gas adsorbent and a moisture adsorbent are inserted. Zeolite was used as the gas adsorbent, and calcium oxide was used as the water adsorbent. The outer box and the inner box are welded at the neck portion of the injection port, and the outer box cut in half is welded at the cut portion, sealed, and then depressurized from the exhaust port to produce a vacuum heat insulation box.

  As a result of measuring the volume of the core material produced under the same conditions as the inserted core material, and then measuring the volume after depressurization, the volume reduction rate was 1.3%. The produced vacuum heat insulation box body was better than Comparative Example 1 without any noticeable change in appearance. In addition, the thermal conductivity is 0.0045 W / mK, which is higher than that of Comparative Example 1.

  Moreover, although it was left to stand at 40 degreeC for 3 months, the change of an external appearance and a performance was not seen, but it was favorable compared with the comparative example 1.

(Embodiment 2)
FIG. 4 is a longitudinal sectional view of the vacuum heat insulation box in the second embodiment of the present invention.

  As shown in FIG. 4, the vacuum heat insulating box 10 includes an outer box 11 and an inner box 12, and a heat insulating space 7 exists between the outer box 11 and the inner box 12. Metal foil 13 is insert-molded inside the outer box 11 and outside the inner box 12. The inside of the heat insulating space 7 is filled with a core material 14 and has a gas adsorbent 8 and a moisture adsorber 9. The heat insulating space 7 is exhausted from the exhaust port 4 to become a decompressed space, and then the exhaust port 4 is sealed to form a sealed space.

(Example 5)
The inner box is a multilayer material having a structure in which two polypropylenes having a thickness of 0.5 mm and an ethylene-vinyl alcohol copolymer (hereinafter referred to as EVOH) having a thickness of 100 μm are sandwiched, and the molding is performed by blow molding. Polypropylene and EVOH are bonded with a bonding material (10 μm).

  A metal foil made of a multilayer material of nylon (10 μm), aluminum foil (20 μm) and polypropylene (7 μm) is placed on the flat surface of the inner surface of the mold at the time of blow molding and integrated into the inner box at the same time as molding. Perform insert molding. The metal foils nylon and aluminum, and aluminum and polypropylene are joined together by a joining material (5 μm). In addition, the metal foil joins the polypropylene side to the inner box.

  The outer box is a multilayer material made of high-density polyethylene having a thickness of 1 mm and an ethylene-vinyl alcohol copolymer (hereinafter referred to as EVOH) having a thickness of 100 μm, and is manufactured by dividing by double injection molding. Polyethylene is mixed with a bonding material to improve adhesion with EVOH.

  The metal foil is a multilayer material of nylon (10 μm), aluminum foil (20 μm), and polyethylene (7 μm), and is placed on the mold flat part at the time of injection molding and insert molded. The metal foils nylon and aluminum, and aluminum and polyethylene are joined together by a joining material (5 μm). Further, the metal foil joins the polyethylene side to the outer box.

  The outer box is preliminarily molded into two parts so that the inner box and the core material can be inserted and joined, and a flange is provided at the joint.

  Moreover, the coverage with the metal foil was 80% of the total surface area.

And the core material solidified in the same three-dimensional shape as the space between an inner box and an outer box is inserted. The core material is prepared by press-molding glass fibers having an average fiber diameter of 7 μm at 450 ° C., adjusting the density to 270 kg / m ³ , and dividing the glass fiber into two parts. Then, the inner box is inserted inside, and further a gas adsorbent and a moisture adsorbent are inserted. Zeolite was used as the gas adsorbent, and calcium oxide was used as the water adsorbent. The outer box and inner box are welded at the neck of the inlet, the outer box is welded with a flange, sealed, and then depressurized from the exhaust port to produce a vacuum heat insulating box.

  As a result of measuring the volume of the core material produced under the same conditions as the inserted core material, and then measuring the volume after decompression, the volume reduction rate was 2.7%. The produced vacuum heat insulation box body was better than Comparative Example 1 without any noticeable change in appearance. Further, the thermal conductivity is 0.0035 W / mK, and it has higher heat insulation performance than Comparative Example 1.

  Moreover, although it was left to stand at 40 degreeC for 3 months, the change of an external appearance and performance was not seen. Furthermore, although it was left to stand at 90 ° C. for 3 months, the performance of the heat insulation box of Example 1 in which the metal foil was not inserted was deteriorated, but the vacuum heat insulation box of Example 5 was good without any change in performance. Met. This is because the gas barrier properties are lowered when EVOH is 90 ° C.

(Embodiment 3)
FIG. 5 is a longitudinal sectional view of the vacuum heat insulation box according to the third embodiment of the present invention.

  As shown in FIG. 5, the vacuum heat insulating box 15 includes an outer box 16 and an inner box 17, and a heat insulating space 7 exists between the outer box 16 and the inner box 17. A resin sheet having a metal vapor deposition film 18 is inserted inside the outer box 16 and outside the inner box 17.

  The inside of the heat insulation space 7 is filled with a core material 19 and has a gas adsorbent 8 and a moisture adsorber 9. The heat insulating space 7 is exhausted from the exhaust port 4 to become a decompressed space, and then the exhaust port 4 is sealed to form a sealed space.

(Example 6)
The inner box is a multi-layer material made of a 100 μm thick ethylene-vinyl alcohol copolymer (hereinafter referred to as EVOH) having a 1.0 mm thick polypropylene and a 1 μm thick aluminum deposited film, and molding is performed by blow molding. . Polypropylene and EVOH are bonded with a bonding material (10 μm).

  The outer box is a multi-layer material consisting of a 100 μm thick ethylene-vinyl alcohol copolymer (hereinafter referred to as EVOH) having a high density polyethylene of 1 mm thickness and an aluminum deposited film of 1 μm thickness. It is divided into two. Polyethylene is mixed with a bonding material to improve adhesion with EVOH. And EVOH which has aluminum vapor deposition is installed in a metal mold | die flat part at the time of injection molding, and insert molding is carried out. EVOH joins the EVOH side with high density polyethylene.

  The outer box is preliminarily molded into two parts so that the inner box and the core material can be inserted and joined, and a flange is provided at the joint.

  Moreover, the coverage with the aluminum vapor deposition film was 80% of the total surface area.

And the core material solidified in the same three-dimensional shape as the space between an inner box and an outer box is inserted. The core material is prepared by press-molding glass fibers having an average fiber diameter of 5 μm at 500 ° C., adjusting the density to 250 kg / m ³ , and dividing the glass fiber into two parts.

  Then, the inner box is inserted inside, and further a gas adsorbent and a moisture adsorbent are inserted. Zeolite was used as the gas adsorbent, and calcium oxide was used as the water adsorbent. The outer box and inner box are welded at the neck portion of the inlet, the outer box is welded with a flange, sealed, and then depressurized from the exhaust port to produce a vacuum heat insulating box.

  As a result of measuring the volume of the core material produced under the same conditions as the inserted core material, and then measuring the volume after depressurization, the volume reduction rate was 3.4%. The produced vacuum heat insulation box body was better than Comparative Example 1 without any noticeable change in appearance. Further, the thermal conductivity is 0.0039 W / mK, and it has high heat insulation performance.

  Moreover, although it was left to stand at 40 degreeC for 3 months, the change of an external appearance and performance was not seen. Furthermore, although it was left to stand at 90 ° C. for 3 months, the performance of the heat insulation box of Example 1 in which the metal foil was not inserted was deteriorated, but the vacuum heat insulation box of Example 6 was good without any change in performance. Met. This is because the gas barrier properties are lowered when EVOH is 90 ° C.

(Embodiment 4)
FIG. 6 shows a regenerative warming device for an automobile to which a vacuum heat insulation box according to Embodiment 4 of the present invention is applied.

  As shown in FIG. 6, the regenerative warming device 20 is a circulation path in which the cooling water warmed by the engine 22 is cooled by the radiator 23 through the cooling water circuit 21 and returned to the engine 22 again. In addition, when the cooling water at the time of starting the engine is not warmed, the thermostat 24 is fully closed, and the cooling water circulates through the bypass passage 25 without passing through the radiator 23 having a heat radiation action, and the temperature of the cooling water is increased. Speed up.

  Further, during continuous running of the automobile, the cooling water warmed in the cooling water circuit 21 flows into the vacuum heat insulating container 29 called a reservoir tank from the switching inlet pipe 27 through the flow rate control valve 26 and is kept warm. Thereafter, when the engine is started, the flow control valve 26 is caused to flow out from the switching outlet pipe 28 to the cooling water circuit and mixed with the cooling water to accelerate the temperature rise of the cooling water. Therefore, it is possible to improve the fuel efficiency of the vehicle when starting the engine.

  The reservoir tank has a vacuum heat insulation space between the metallic inner container and outer container like a so-called thermos, and there are restrictions on the shape in terms of strength, and a simple shape such as a cylindrical shape is generally used. Is. However, the vacuum heat insulation container of the present invention has a high degree of freedom in molding, can form a reservoir tank with a complicated shape, has low heat leak, excellent heat insulation performance, long-term reliability, and improved heat retention efficiency To do.

  Moreover, it is desirable that the inner surface of the inner box of the vacuum heat insulating box used for the heat storage type warming device is a water resistant resin. By covering the inner surface of the inner box with a water-resistant resin, it is possible to prevent moisture from penetrating even when the cooling water is kept warm in the tank, and to improve durability.

  Further, the water-resistant resin is not limited as long as it has water resistance, but if it is polypropylene, polyester resin, or fluorine resin, it is excellent in water resistance and is a general-purpose resin, so it is inexpensive.

(Embodiment 5)
FIG. 7 is a longitudinal sectional view of a refrigerator to which a vacuum heat insulating box according to Embodiment 5 of the present invention is applied.

  The refrigerator 30 has a vacuum heat insulating box structure, and includes an inner box 31 constituting the inside of the refrigerator and an outer box 32 constituting the outer wall, and a heat insulating layer 33 exists between the inner box 31 and the outer box 32. The outer box 32 is made of a PCM steel plate, and the inner box 31 is made of an ABS resin obtained by insert-molding an aluminum foil, and the aluminum foil is on the heat insulating layer side. The inside of the heat insulation layer 33 is filled with a core material 34 and has a gas adsorbent 35 and a moisture adsorbent 36. In addition, the refrigerator 30 has an exhaust port 37 on the back surface and a machine room 38 at the lower back side, and a compressor 39 is mounted in the machine room 38. Isobutane is used as the refrigerant.

(Example 7)
The core material is made of glass fibers having an average fiber diameter of 5 μm, coated with a 3 wt% sodium silicate solution as a binder, dried in a solvent while pressing at 450 ° C. into the shape of the heat insulating layer, and solidified.

  The inner box is a multilayer material in which aluminum foil (10 μm) is insert-molded into 3 mm thick ABS resin and 20 μm thick ethylene-vinyl alcohol copolymer (hereinafter referred to as EVOH). Is performed by vacuum / pressure forming.

  The outer box is a 1 mm thick PCM steel plate and is formed by press molding. The core material is inserted between the outer box and the inner box, and the outer box and the inner box are joined at the contact portion.

  The heat insulating layer is depressurized from the exhaust port by a vacuum pump outside the refrigerator, and seals the exhaust port portion when the degree of vacuum reaches about 30 Pa.

  Further, since the volume change rate of the core material is as small as 1%, a vacuum insulated box refrigerator having high reliability without dents and distortions is formed.

  Next, a comparative example for the adsorbent of the present invention is shown.

(Comparative Example 1)
The inner box is a multilayer material made of polypropylene having a thickness of 1 mm and an ethylene-vinyl alcohol copolymer (hereinafter referred to as EVOH) having a thickness of 100 μm. The polypropylene is on the inside, and molding is performed by blow molding. Polypropylene and EVOH are bonded with a bonding material (10 μm).

  The outer box is a multi-layer material consisting of high density polyethylene with a thickness of 1 mm and EVOH with a thickness of 100 μm. The high density polyethylene is on the outside. Like the inner box, the outer box is made by blow molding. 10 μm). The outer box formed by blow molding is cut in half, and a core material is inserted between the inner box and the outer box.

  As the core material, glass fibers having an average fiber diameter of 5 μm are inserted. Then, the inner box is inserted inside, and further a gas adsorbent and a moisture adsorbent are inserted. Zeolite was used as the gas adsorbent, and calcium oxide was used as the water adsorbent. The outer box and the inner box are welded at the neck portion of the injection port, and the outer box cut in half is welded at the cut portion, sealed, and then depressurized from the exhaust port to produce a vacuum heat insulation box.

  As a result of measuring the volume of the core material produced under the same conditions as the inserted core material, and then putting it in a laminate film and measuring the volume after decompression, the volume reduction rate was 56%. The produced vacuum heat insulation box was greatly deformed, and the thermal conductivity was 0.0125 W / mK.

  In addition, cracks occurred when left at 40 ° C. for 1 month.

  As described above, the vacuum heat insulation box according to the present invention can reduce the load applied to the box by decompression, can constitute a vacuum heat insulation box excellent in long-term reliability and appearance, and can exhibit excellent heat insulation performance. It can be applied to various heat insulation applications such as thermal storage devices for automobiles, heating / cooling devices such as refrigerator-freezers and refrigeration devices, and objects to be protected from heat and cold.

External appearance perspective view of the vacuum heat insulation box in Embodiment 1 of this invention The disassembled perspective view of the vacuum heat insulation box in Embodiment 1 of this invention The longitudinal cross-sectional view of the vacuum heat insulation box in Embodiment 1 of this invention The longitudinal cross-sectional view of the vacuum heat insulation box in Embodiment 2 of this invention The longitudinal cross-sectional view of the vacuum heat insulation box in Embodiment 3 of this invention Schematic of the regenerative warming device for automobiles to which the vacuum heat insulation box according to Embodiment 4 of the present invention is applied The longitudinal cross-sectional view of the refrigerator which applied the vacuum heat insulation box by Embodiment 5 of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vacuum heat insulation box 3 Outer box 5 Inner box 6 Core material 7 Heat insulation space 10 Vacuum heat insulation box 11 Outer box 12 Inner box 13 Metal foil 14 Core material 15 Vacuum heat insulation box 16 Outer box 17 Inner box 19 Core material 29 Vacuum Heat insulation container 30 Refrigerator 31 Inner box 32 Outer box 33 Heat insulation layer 34 Core material

Claims (5)

  A vacuum heat insulation box having a vacuum heat insulation structure comprising at least an outer box and an inner box made of a gas barrier material, and a core material sealed under reduced pressure in a space constituted by the outer box and the inner box, A vacuum heat insulation box characterized in that the volume change rate before and after decompression of the core is within 50%.   The vacuum heat insulating box according to claim 1, wherein the core material has a three-dimensional shape.   The vacuum heat insulation box according to claim 2, wherein the three-dimensional core material is divided into at least two.   The vacuum heat insulating box according to any one of claims 1 to 3, wherein the gas barrier material is a multilayered resin material and metal foil.   The resin material is ethylene-vinyl alcohol copolymer, polyacrylonitrile, polyamide 6, polyamide 11, polyamide 12, polybutylene terephthalate, polybutylene naphthalate, polyethylene naphthalate, polyvinylidene fluoride, polyvinylidene chloride, ethylene-tetrafluoroethylene. The vacuum heat insulation box according to claim 4, wherein at least one of the group consisting of a copolymer, polytetrafluoroethylene, polyphenylene fluoride, polyetheretherketone, and polyimide is used.

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