JP2018109424A - Vacuum heat insulation material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vacuum heat insulation material capable of being easily manufactured, and having improved handleability and heat storage capacity.SOLUTION: A sealed heat storage material is decompressed and sealed together with a core material and absorbent, into a gas-barrier film, and then the heat storage material is included in a vacuum heat insulation material.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a vacuum heat insulating material.

  In recent years, energy saving and resource saving are strongly desired from the viewpoint of global warming prevention and the like. In particular, efficient use of thermal energy in the fields of household, commercial appliances such as refrigerators, freezers, heat insulation boxes, jar rice cookers, water heaters, vending machines, automobiles, photocopiers, floor heating, and houses. From the viewpoint of doing, a vacuum heat insulating material is used.

  Conventionally, a heat storage material is used in combination with a heat insulating material in order to keep the heat insulation performance of the heat insulating box or house indoors constant. Patent document 1 is related with the thermal storage thermal insulation body which laminated | stacked the thermal storage body and the heat insulating body, and has arrange | positioning a thermal storage thermal insulation body inside a heat insulation box. Patent document 2 is disclosing the heat insulation panel for buildings provided with the vacuum heat insulating material, the latent heat storage material which covered the predetermined location of the vacuum heat insulating material, and the heat insulating material which covered the latent heat storage material and the vacuum heat insulating material. . In patent document 2, the heat leak amount in a vacuum heat insulating material is relieved by the amount of latent heat of a heat storage material by covering the predetermined location of a vacuum heat insulating material with a heat storage material.

JP 2006-045492 A International Publication No. 2011/104873 Pamphlet

  In the heat insulation box of patent document 1, if a heat storage insulation body is put in a box, the problem that the space in a box will become narrow arises. Moreover, in the heat insulation panel for building of patent document 2, since the latent heat storage material has covered the predetermined location outside the vacuum heat insulating material, the amount of latent heat of the heat storage material is immediately saturated by the heat transmitted from the outside of the panel. There is a problem of end.

  In order to solve these problems, an attempt was made to include a heat storage material inside the vacuum heat insulating material. However, when the heat storage material is handled alone, a phase change from a solid to a liquid or from a liquid to a gas is caused at a temperature equal to or higher than the latent heat temperature, and gasifies. Therefore, when the heat storage material is included in the vacuum heat insulating material as it is, a problem arises that the degree of vacuum of the vacuum heat insulating material is reduced due to gasification of the heat storage material.

  The subject of this invention is providing the vacuum heat insulating material provided with the improved handling property and heat storage capacity which can be manufactured simply.

  It has been found that the above problem can be solved by sealing the sealed heat storage material together with the core material and the adsorbent in a gas barrier film under reduced pressure and including the heat storage material inside the vacuum heat insulating material. That is, the present invention relates to the following [1] to [18].

[1] A vacuum heat insulating material including a core material, an adsorbent, a heat storage material, and a gas barrier film,
The heat storage material is sealed,
The core material, the adsorbent and the sealed heat storage material are sealed under reduced pressure in the gas barrier film,
A vacuum insulation material characterized by that.

[2] The vacuum heat insulating material according to [1], wherein the heat storage material is sealed with a capsule, a film, or a binder.

[3] The vacuum heat insulating material according to [2], wherein the heat storage material is sealed with a capsule, and the capsule is made of an inorganic capsule or a melamine capsule.

[4] The vacuum heat insulating material according to [2], wherein the heat storage material is sealed with a film, and the film includes a film including a metal foil layer or a film including a metal vapor deposition layer.

[5] The vacuum heat insulating material according to [2], wherein the heat storage material is sealed with a binder, and the binder is made of a resin or an inorganic compound.

[6] In the gas barrier film, the core material and the heat storage material are each layered, and the core material layer and the heat storage material layer are laminated, [1] to [5] The vacuum heat insulating material of any one of these.

[7] The vacuum heat insulating material according to [6], wherein the gas barrier film has a two-layer structure including the core material layer and the heat storage material layer.

[8] The gas barrier film has a three-layer structure including two layers of the core material and the heat storage material layer sandwiched between the two core material layers. The vacuum heat insulating material described in 1.

[9] The above [1] to [5], wherein the core material forms a layer, and the heat storage material covers 70% or more of the area of one surface of the core material layer. The vacuum heat insulating material according to item 1.

[10] The vacuum heat insulating material according to any one of [1] to [9], including the heat storage material of less than 80% by mass with respect to the total mass of the vacuum heat insulating material.

[11] The vacuum heat insulating material according to any one of [1] to [10], wherein a latent heat temperature of the heat storage material is −60 to 100 ° C.

[12] The vacuum heat insulating material according to any one of [1] to [11], wherein a latent heat amount of the heat storage material is 60 to 350 J / g.

[13] The heat storage material is selected from the group consisting of calcium chloride hydrate, sodium sulfate hydrate, sodium thiosulfate hydrate, sodium acetate hydrate, vanadium oxide, paraffin, erythritol, and mixtures thereof. The vacuum heat insulating material according to any one of [1] to [12].

[14] A heat insulating box including the vacuum heat insulating material according to any one of [1] to [13].

[15] A heat insulating box including the vacuum heat insulating material according to [7] for keeping the inside of the box at a lower temperature than the outside, wherein the heat storage material layer is disposed on the inside of the box, Insulated box.

[16] A heat insulating box including the vacuum heat insulating material according to [8] for keeping the inside of the box at a lower temperature than the outside, wherein the layer of the heat storage material is at the center in the thickness direction of the vacuum heat insulating material. The said heat insulation box arrange | positioned or arrange | positioned inside the box rather than the center.

[17] A heat insulating box including the vacuum heat insulating material according to [7] for keeping the inside of the box at a higher temperature than the outside, wherein the heat storage material layer is disposed on the outside of the box, Insulated box.

[18] A heat insulation box including the vacuum heat insulating material according to [8] for keeping the inside of the box at a higher temperature than the outside, wherein the layer of the heat storage material is at the center in the thickness direction of the vacuum heat insulating material. The said heat insulation box arrange | positioned or arrange | positioned in the box outer side rather than the center.

  By this invention, the vacuum heat insulating material provided with the improved handleability and heat storage capability which can be manufactured simply is provided.

FIG. 1 shows the calibration result of the thermal conductivity checker. FIG. 2 shows the result of the box internal temperature rise test.

  The present invention is a vacuum heat insulating material including a core material, an adsorbent, a heat storage material, and a gas barrier film, wherein the heat storage material is sealed, and the core material, the adsorbent, and the sealed heat storage material are A vacuum heat insulating material characterized by being sealed under reduced pressure in the gas barrier film.

As a core material used for this invention, what is used in the vacuum heat insulating material field | area can be especially used without a restriction | limiting. For example, inorganic fibers, fibers in which inorganic fibers and organic fibers are mixed, powder core materials mainly composed of silica particles, foam heat insulating materials, and the like can be used as the core materials. The main component of the core material is preferably glass fibers or silica particles containing SiO ₂ .
Core materials are known and are readily available in the market or can be prepared.
The vacuum heat insulating material of the present invention preferably contains the core material in an amount of 20 to 95% by mass, more preferably 40 to 80% by mass, based on the total mass of the vacuum heat insulating material. When the amount of the core material is within the above range, the heat storage effect can be effectively exhibited without impairing the function as the heat insulating material.

  The gas barrier film used in the present invention is not particularly limited as long as it is a film having a gas barrier property, but is preferably a laminate of a seal layer and a gas barrier layer. The seal layer, the gas barrier layer, and the resin are sequentially formed from the side in contact with the core material. What laminated | stacked the film layer is more preferable. The thickness of the gas barrier film is not particularly limited, but is usually 5 to 60 μm, and preferably 6 to 30 μm. A gas barrier layer is a layer which does not permeate | transmit gas, and is used from a viewpoint which prevents the fall of the vacuum degree of a vacuum heat insulating material.

  Examples of the gas barrier layer include metal foil and a laminated film (deposited film) obtained by vapor deposition on a resin film. Examples of the metal of the metal foil include aluminum, copper, stainless steel, and iron. Preferably, aluminum is used. The vapor deposition film is formed by vapor deposition of a metal such as aluminum, stainless steel, cobalt, nickel, or the like, silica, alumina, or a combination thereof by a vapor deposition method, a sputtering method, or the like. Examples of the resin film used as the base material for the deposited film include aromatic polyester resins such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT); polyolefin resins such as polyethylene, polypropylene and olefin copolymers; polyvinyl chloride , Vinyl chloride resins such as vinyl chloride copolymer; polyamide resins such as nylon 6, nylon 66, metaxylylenediamine / adipic acid condensate; polyvinyl alcohol, acrylonitrile / butadiene / styrene copolymer, acrylonitrile / styrene copolymer Styrenic resin such as coalescence; acrylic resin such as polymethyl methacrylate, acrylic acid ester and methyl methacrylate copolymer, ethylene-vinyl alcohol copolymer, polyvinyl alcohol and this The object such as a thermoplastic resin, a phenol resin, a film made from a thermosetting resin of urea resin, etc. are used. The gas barrier layer is preferably an aluminum foil. Although the thickness of a gas barrier layer does not have a restriction | limiting in particular, Usually, it is 5-60 micrometers, Preferably it is 6-30 micrometers. The metal foil and vapor deposition film used for the gas barrier layer are known and can be easily obtained or prepared in the market.

The seal layer is a resin that can be fused by heating. There is no particular limitation as long as the resin can be heat-sealed. Specifically, a film made of a polyolefin resin such as polyethylene or polypropylene, polyacrylonitrile, PET, an ethylene-vinyl alcohol copolymer, or a mixture thereof can be used. Preferably, polyethylene, polypropylene, and ethylene-vinyl alcohol copolymer are used. The polyethylene preferably has a density of 0.90 to 0.98 g / cm ³ . The polypropylene preferably has a density of 0.85 to 0.95 g / cm ³ . Although there is no restriction | limiting in particular in the thickness of a sealing layer, Usually, it is 10-100 micrometers, Preferably it is 25-60 micrometers. Resins used for the sealing layer are known and can be easily obtained in the market or can be prepared.

  The resin film layer is a layer arbitrarily provided on the gas barrier layer for the purpose of protecting the gas barrier layer. As the resin film layer, aromatic polyester resins such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT); polyolefin resins such as polyethylene, polypropylene and olefin copolymers; polyvinyl chloride, vinyl chloride copolymers and the like Polyvinyl resins such as nylon 6, nylon 66, metaxylylenediamine / adipic acid condensates, etc .; styrene resins such as polyvinyl alcohol, acrylonitrile / butadiene / styrene copolymers, acrylonitrile / styrene copolymers; Films made from thermoplastic resins such as acrylic resins such as polymethyl methacrylate, acrylic acid ester and methyl methacrylate copolymer, and thermosetting resins such as phenol resin and urea resin are used. Preferably, PET, nylon 6 or nylon 66 is used. Organic and inorganic fillers can also be added to these resin films. These resins can be used alone or in admixture of two or more. In order to further improve the gas barrier performance of the gas barrier film, a gas barrier resin obtained by polymerizing and copolymerizing vinyl monomers such as vinylidene chloride, acrylonitrile, and vinyl alcohol is applied to the resin film layer or laminated. These particles can be mixed and dispersed in the resin film layer. Although there is no restriction | limiting in particular in the thickness of a resin film layer, Usually, it is 5-40 micrometers, Preferably it is 10-30 micrometers. Resins used for the resin film layer are known and can be easily obtained in the market or can be prepared.

  The adsorbent used in the present invention is not particularly limited as long as it is a substance that adsorbs gas. For example, it is a substance that adsorbs gas such as nitrogen, oxygen, carbon dioxide, and / or moisture. Examples of the adsorbent include calcium oxide, silica gel, zeolite, activated carbon, barium oxide, barium-lithium alloy, porous coordination polymer, metal organic structure, or a mixture thereof. From the viewpoint of gas adsorption performance and productivity, calcium oxide is preferable. Adsorbents are known and can be readily obtained in the market or can be prepared.

The vacuum heat insulating material of the present invention includes a heat storage material. The “heat storage material” represents a material having a large heat capacity or a latent heat storage material. A latent heat storage material is a substance that exhibits a heat storage effect with thermal energy consumed or stored during phase change.
Examples of the heat storage material include calcium chloride hydrate, sodium sulfate hydrate, sodium thiosulfate hydrate, sodium acetate hydrate, vanadium oxide, paraffin, erythritol and the like. These heat storage materials may be used alone or in combination of two or more.

  Although the kind of heat storage material can be set according to the use of a vacuum heat insulating material, it is preferable that latent heat temperature is -60-100 degreeC, and it is more preferable that it is 0-50 degreeC. “Latent heat temperature” refers to the temperature at which the heat storage material undergoes a phase change. If the latent heat temperature is within the above range, the heat storage performance according to the purpose can be exhibited.

The amount of latent heat of the heat storage material is preferably 60 to 350 J / g, more preferably 80 to 350 J / g. When the amount of latent heat is within the above range, a high heat retention effect can be expected when combined with a heat insulating material. The “latent heat amount” represents the amount of heat that the latent heat storage material can store. When the heat storage material is sealed in a capsule or the like, the “latent heat amount” indicates the latent heat amount of the latent heat material itself.
Thermal storage materials are known and can be readily obtained or prepared on the market.
The vacuum heat insulating material of the present invention preferably contains a heat storage material with respect to the total mass of the vacuum heat insulating material, less than 80% by mass, and more preferably 20-60% by mass. If the amount of the heat storage material is within the above range, the heat storage performance can be imparted to the vacuum heat insulating material while maintaining the heat insulation performance.

  In the present invention, the heat storage material is sealed. By sealing the heat storage material, gasification of the heat storage material can be prevented, and the vacuum degree of the vacuum heat insulating material can be kept high.

The heat storage material is preferably sealed with a capsule, a film, a binder or the like. Examples of capsules include inorganic capsules, melamine capsules, and metal capsules. The inorganic capsule may include a capsule mainly made of silica (SiO ₂ ) or alumina (Al ₂ O ₃ ). The metal capsule may include aluminum, copper, stainless steel, and the like. As a film, the film containing a metal foil layer, the film containing a metal vapor deposition layer, etc. are mentioned. The metal foil layer may include, for example, aluminum foil, copper foil, nickel foil, stainless steel foil, and the like. The metal deposition layer may include, for example, an aluminum deposition layer, an aluminum oxide deposition layer, a silica deposition layer, and the like. Examples of the binder include resins and inorganic compounds. As the resin, for example, phenol resin, acrylic resin, epoxy resin, urea resin, melamine resin, polyurethane, polyester, ABS resin, vinyl chloride resin, polypropylene, polypropylene polystyrene, and the like can be used. As the inorganic compound, for example, alkali metal silicate-based, phosphate-based, silica sol-based, alumina and the like can be used.

  When the heat storage material is sealed with the capsule, a plurality of capsules including the heat storage material may be put in the holding material to adjust the shape. The plurality of capsules to be put in the holding material may be one type of capsule containing the same heat storage material, or may be a mixture of two or more types of capsules containing different heat storage materials. As the holding material, any material that does not generate gas under vacuum can be used without particular limitation. The holding material may be a nonwoven fabric or a woven fabric. The fiber used as the material of the woven fabric can be used without particular limitation as long as it does not generate organic gas. Natural fibers such as plant fibers and animal fibers, aramid fibers, glass fibers, cellulose fibers, and nylon fibers can be used. Synthetic fibers such as vinylon fiber, polyester fiber, polyethylene fiber, polypropylene fiber, polyolefin fiber, rayon fiber, and the like can be used. The fiber used as the material of the nonwoven fabric can be used without any limitation as long as it does not generate an organic gas under vacuum. For example, aramid fiber, glass fiber, cellulose fiber, nylon fiber, vinylon fiber, polyester fiber, polyethylene Examples thereof include synthetic fibers such as fibers, polypropylene fibers, polyolefin fibers, and rayon fibers.

  When the heat storage material is sealed with a binder, the heat storage material may be mixed with the binder and formed into a plate shape, for example. Depending on the molding method, a part of the heat storage material may be exposed on the surface of the molded product. In this case, the heat storage material exposed on the surface is gasified before manufacturing the vacuum heat insulating material, so that the final product All the heat storage materials contained in the vacuum heat insulating material are sealed with a binder. For example, when the curing temperature of the binder is 100 ° C. or higher, the heat storage material exposed to the surface by the heat treatment for curing the binder volatilizes, and the heat storage material taken into the binder does not volatilize. Moreover, when the curing temperature of the binder is less than 100 ° C., it is exposed to the surface by heating for about 1 hour at 100 ° C. or higher, more preferably 150 ° C. or higher, as a pretreatment for manufacturing vacuum heat insulating material. The heat storage material is volatilized, and the generation of gas derived from the heat storage material inside the vacuum heat insulating material can be prevented.

  In the vacuum heat insulating material of the present invention, the core material, the adsorbent and the sealed heat storage material are sealed under reduced pressure in the gas barrier film. Since the vacuum heat insulating material of the present invention is integrated with the heat storage material, it is excellent in handleability. The internal pressure of a vacuum heat insulating material is 0.5-20 Pa, for example, Preferably it is 0.5-10 Pa. If the internal pressure is within the above range, the gas thermal conductivity can be almost ignored, so that high heat insulation can be secured.

  In one aspect, the core material and the heat storage material each have a layered shape, and the core material layer and the heat storage material layer may be laminated. The vacuum heat insulating material may have a two-layer structure including a core material layer and a heat storage material layer in the gas barrier film. Alternatively, the vacuum heat insulating material may have a three-layer structure including two core material layers and a heat storage material layer sandwiched between the two core material layers in the gas barrier film.

  In another aspect, the core material may form a layer, and the heat storage material may cover 70% or more, more preferably 80% or more of the area of one surface of the core material layer. If the covering ratio by the heat storage material is within the above range, the heat from the high temperature side can be stored effectively. There is no particular limitation on the area covered with the heat storage material, but if the heat storage material is placed so as to cover the edge of one side of the core material layer, the heat leaking from the heat bridge can be effectively latent heat. Can do.

  The vacuum heat insulating material of this invention is used suitably for a heat insulation box. Since the vacuum heat insulating material of the present invention is integrated with the heat storage material, it is not necessary to separately arrange the heat storage material in the box, and the space in the box can be used effectively. The heat insulating box may be for keeping the inside of the box at a lower temperature than the outside, or may be for keeping the inside of the box at a higher temperature than the outside.

  In the vacuum heat insulating material used for the heat insulating box, it is preferable that the layer of the heat storage material is disposed on the low temperature side. For example, in a heat insulation box using a vacuum heat insulating material having a two-layer structure consisting of a core material layer and a heat storage material layer, when keeping the inside of the box at a lower temperature than the outside, the heat storage material layer is placed on the inside of the box. It is preferable to arrange, and when the inside of the box is kept at a higher temperature than the outside, it is preferable to arrange the layer of the heat storage material on the outside of the box. In a heat insulation box using a vacuum heat insulating material having a three-layer structure composed of two core material layers and a heat storage material layer sandwiched between the two core material layers, the inside of the box is more external than the outside. When keeping at a low temperature, the layer of the heat storage material is preferably arranged at the center in the thickness direction of the vacuum heat insulating material or on the inner side of the box from the center. It is preferable to arrange the material layer at the center in the thickness direction of the vacuum heat insulating material or on the outside of the box from the center. The position of the heat storage material can be specified by the center position in the thickness direction of the layer of the heat storage material. For example, when the center position in the thickness direction of the heat storage material layer coincides with the center in the thickness direction of the vacuum heat insulating material, the heat storage material layer is disposed in the center in the thickness direction of the vacuum heat insulating material.

You may set the kind of heat storage material according to the temperature of the position which arrange | positions a heat storage material in a heat insulation box. The temperature T at the position where the heat storage material is arranged can be expressed by the following formula (I).

T = T1-{(T1-T2) / L} * d (I)

T: Temperature of the position where the heat storage material is disposed T1: Temperature on the high temperature side T2: Temperature on the low temperature side d: Distance from the surface on the high temperature side of the vacuum heat insulating material to the position where the heat storage material is disposed L: Thickness of the vacuum heat insulating material

As the heat storage material, it is preferable to use a heat storage material having a latent heat temperature close to the temperature at which the heat storage material is disposed. Specifically, when the layer of the heat storage material is disposed at the center in the thickness direction of the vacuum heat insulating material or on the lower temperature side than the center, the latent heat temperature T ′ of the heat storage material is equal to or higher than the temperature on the low temperature side and the center temperature. It is preferably + 10 ° C. or lower (T2 ≦ T ′ ≦ (T1 + T2) / 2 + 10 ° C.). For example, in the case of a heat-insulated container for maintaining the inside at −80 ° C. like a deep freezer, if the outside air temperature is 20 ° C., the center temperature of the heat insulating material is −30 ° C. It is preferable to select a heat storage material that causes latent heat below. For example, in the case of a heat insulating container that keeps the inside at 0 ° C., if the outside air temperature is 30 ° C., the center temperature of the heat insulating material is 15 ° C., so select a heat storage material that can latently heat at 0 ° C. to 25 ° C. It is preferable. When the latent heat temperature is within the above range, the latent heat effect of the heat storage material is more efficiently exhibited, and the heat retaining performance of the heat insulating box is improved.

  There is no restriction | limiting in particular in the manufacturing method of the vacuum heat insulating material of this invention. For example, the manufacturing method includes a step of forming a gas barrier film in a bag shape, a step of disposing a core material, an adsorbent and a heat storage material in the bag-shaped gas barrier film, a core material, an adsorbent and a heat storage material in the gas barrier film. A step of sealing under reduced pressure may be included. The vacuum heat insulating material of the present invention is manufactured by arranging the heat storage material together when the core material and the adsorbent are arranged in the gas barrier film in the conventional vacuum heat insulating material manufacturing method not including the heat storage material. Can do. That is, the vacuum heat insulating material of the present invention can be easily manufactured as in the conventional vacuum heat insulating material, and the manufacturing cost can be suppressed.

  There is no restriction | limiting in particular in the method of manufacturing a heat insulation box using the vacuum heat insulating material of this invention. For example, a heat insulating box can be manufactured by fixing six vacuum heat insulating materials in a box shape using a tape or the like. Alternatively, in a box having an outer box and an inner box, the heat insulating box can be manufactured by inserting the vacuum heat insulating material of the present invention between the outer box and the inner box and holding it by urethane injection foaming or the like.

  The vacuum heat insulating material of the present invention can be applied to the same use as that of a conventional vacuum heat insulating material, particularly to a product that maintains the internal temperature. For example, it can be used in household, commercial appliances such as heat insulation boxes, refrigerators, freezers, jar rice cookers, water heaters, vending machines, automobiles, copiers, floor heating, houses, cold containers, refrigerated warehouses, etc. .

Example 1
Vacuum heat insulating material with heat storage material (1) Production of vacuum heat insulating material with heat storage material Paraffin (latent heat amount 242 J / g) having a latent heat temperature of 25 ° C. was sealed in a melamine capsule. A capsule containing 100 g of a heat storage material was put in a polyester fiber non-woven fabric and heat-sealed to form a layer. A heat storage material layer is laminated on a glass fiber core layer or sandwiched between two core material layers, and a gas barrier film (a multilayer laminate film including an aluminum foil as a gas barrier layer) together with a moisture adsorbent (calcium oxide) A vacuum heat insulating material containing a heat storage material (300 mm in length, 300 mm in width, 10 mm in thickness) having a two-layer structure or a three-layer structure in a gas barrier film was produced.

(2) Calibration of the thermal conductivity measuring device In a vacuum heat insulating material having a thermal conductivity of 1.22 mW / mK, 2.18 mW / mK and 3.30 mW not including a heat storage material, a heat conductivity checker (HC) manufactured by Eihiro Seiki -120) was measured. The results are shown in Table 1 and FIG.

(3) Measurement of thermal conductivity of vacuum heat insulating material containing heat storage material Based on the relationship between the thermal conductivity indicated by a straight line in FIG. 1 and the output value, a vacuum heat insulating material containing a heat storage material having a two-layer structure in the gas barrier film ( About 5 samples), the sensor head of HC-120 was brought into contact with the surface of the vacuum heat insulating material on the core material layer side, and the thermal conductivity was measured. When the thermal conductivity was 3 mW / mK or less, it was determined that it had good heat insulation performance (◯). The results are shown in Table 2.

  Similarly, about the heat insulating material-containing vacuum heat insulating material (5 samples) having a three-layer structure in the gas barrier film, the thermal conductivity was measured by bringing the HC-120 sensor head into contact with one surface of the vacuum heat insulating material. . The results are shown in Table 3.

  As a result of the measurement, it was confirmed that any heat insulating material-containing vacuum heat insulating material has good heat insulating performance. Therefore, it is considered that the heat storage material is not gasified in the vacuum heat insulating material.

Example 2
Heat insulation box made of vacuum heat insulating material containing heat storage material (1) Selection of heat storage material A heat insulating box used at an external temperature of 60 ° C and an internal temperature of 20 ° C was assumed, and the type of latent heat material to be used was determined. When the layer of the latent heat material is arranged at the center in the thickness direction of the vacuum heat insulating material or at a lower temperature side than the center, the latent heat temperature T ′ of the latent heat material is not less than the temperature on the low temperature side and not more than the center temperature + 10 ° C. It is preferable that it is 50 degreeC. Accordingly, paraffin having a latent heat temperature of 25 ° C. (heat storage material 25) (latent heat amount 242 J / g) and paraffin having a latent heat temperature of 32 ° C. (heat storage material 32) (latent heat amount 247 J / g) are contained in the vacuum heat insulating material. Selected as a heat storage material to include. Since paraffin changes its phase to liquid or gas when absorbing heat, it was sealed with an inorganic capsule mainly composed of SiO ₂ so as not to be gasified.

(2) Manufacture of vacuum heat insulating material The heat storage material-containing capsule of (1) was put in a polyester fiber non-woven fabric and heat-sealed to prepare a heat storage material layer. As the heat storage material layer, a layer containing only the capsule containing the heat storage material 25 (heat storage material 25 layer), a layer containing only the capsule containing the heat storage material 32 (32 layers of heat storage material), a capsule containing the heat storage material 25 and a capsule containing the heat storage material 32 Three types of heat storage material layers, ie, a layer (MIX layer) containing a mass ratio of 1: 1 was prepared. Moreover, a core material (glass fiber mat), a gas barrier film (a multilayer laminate film including an aluminum foil as a barrier layer), and an adsorbent (calcium oxide) were prepared as materials for the vacuum heat insulating material.
(A) Manufacture of the vacuum heat insulating material (comparative VIP) which does not contain a thermal storage material The core material was dried at 200 degreeC for 1 hour, and the water | moisture content adhering to the surface was removed. The gas barrier film was dried at 80 ° C. for 2 hours so that the inner sealing layer did not melt. A core material and an adsorbent were inserted inside the dried gas barrier film, and sealed under reduced pressure at a final ultimate pressure of 0.5 Pa using a vacuum chamber.
(B) Manufacture of vacuum heat insulating material having a two-layer structure in a gas barrier film When inserting a core material and an adsorbent into the inside of a dried gas barrier film, 25 layers of heat storage material, 32 layers of heat storage material or MIX layer A vacuum heat insulating material having a two-layer structure in a gas barrier film was produced in the same manner as in Comparative VIP except that it was laminated on the core material. Content of the heat storage material in the obtained vacuum heat insulating material was 40 mass%.
(C) Manufacture of a vacuum heat insulating material having a three-layer structure in a gas barrier film When inserting a core material and an adsorbent inside a dried gas barrier film, 25 layers of heat storage material between two layers of the core material Alternatively, in the gas barrier film, in the same manner as the comparative VIP except that the heat storage material 32 layer is sandwiched so that the center in the thickness direction of the heat storage material 25 layer or the heat storage material 32 layer is positioned in the center in the thickness direction of the laminate. A vacuum heat insulating material having a three-layer structure was manufactured. Content of the heat storage material in the obtained vacuum heat insulating material was 40 mass%.

(3) Production of heat insulation box (2) Six comparative VIPs produced in (a) were fixed in a box shape using polypropylene tape to produce a comparison box.
(2) Six vacuum heat insulating materials each having a two-layer structure in the gas barrier film produced in (b) are fixed in a box shape using polypropylene tape, and 25 layers of heat storage material are arranged on the inner side. A heat insulation box (inside the heat storage material 25), a heat insulation box (inside the heat storage material 32) in which the heat storage material 32 layer is arranged on the inner side, and a heat insulation box (inside MIX) in which the MIX layer is arranged on the inner side were manufactured.
(2) Six vacuum insulation materials having a three-layer structure in the gas barrier film produced in (c) are fixed in a box shape using polypropylene tape, and 25 layers of heat storage material are arranged in the middle of the vacuum insulation material. The heat insulation box (heat storage material 25 middle) and the heat insulation material 32 layer in which the heat storage material 32 layer was arrange | positioned in the middle of the vacuum heat insulation material were manufactured.

(4) Box internal temperature rise test Under the following test conditions, the internal temperature rise of each heat insulation box manufactured in (3) was measured. GL240 from GRAPHTEC was used as a data logger.

(I) The heat insulation box was preheated to 20 ° C. with the lid opened.
(Ii) Thermocouples were attached at two locations inside the box (center) and outside the wall of the box, and the lid was closed.
(Iii) The temperature was kept at 20 ° C. for 1 hour, and then the temperature was raised from 20 ° C. to 60 ° C. over 20 minutes. The start of temperature increase was defined as the start of measurement (0 minutes).
(Iv) A temperature of 60 ° C. was maintained.

The results are shown in Table 4 and FIG.

  In the case of the comparison box, the internal temperature reached the external surface temperature in about 1 hour. In the case of the inside of the heat storage material 25, the state of heat storage was confirmed at around 25 ° C. Although the temperature increase rate increased after about 2 hours, the temperature increase was suppressed more than the comparison box. In the case of the inside of the heat storage material 32, the state of heat storage was confirmed from around 32 ° C. The internal temperature after 4 hours was almost the same as that inside the heat storage material 25. On the other hand, regarding the middle of the heat storage material 25 and the middle of the heat storage material 32, the temperature increase in the middle of the heat storage material 32 was slower between 60 minutes and 180 minutes than in the middle of the heat storage material 25. This is because when the internal temperature is 20 ° C./the outer surface temperature is 60 ° C., the center temperature is 40 ° C., and the difference between the center temperature and the latent heat temperature of the heat storage material is smaller in the middle of the heat storage material 32, so the latent heat is more effective. It is thought that it was because it was made.

  The vacuum heat insulating material of the present invention improves the heat insulation performance of the box by using it in a box intended for cold insulation and heat insulation, and therefore reduces the power, cold insulation, heat insulation agent, etc. necessary to maintain the internal temperature. It becomes possible. Moreover, the vacuum heat insulating material of this invention is useful as a means for keeping constant the quality of the target object preserve | saved in a box.

Claims (18)

A vacuum heat insulating material including a core material, an adsorbent, a heat storage material and a gas barrier film,
The heat storage material is sealed,
The core material, the adsorbent and the sealed heat storage material are sealed under reduced pressure in the gas barrier film,
A vacuum insulation material characterized by that.   The vacuum heat insulating material according to claim 1, wherein the heat storage material is sealed with a capsule, a film, or a binder.   The vacuum heat insulating material according to claim 2, wherein the heat storage material is sealed by a capsule, and the capsule is made of an inorganic capsule or a melamine capsule.   The vacuum heat insulating material according to claim 2, wherein the heat storage material is sealed by a film, and the film is made of a film including a metal foil layer or a film including a metal vapor deposition layer.   The vacuum heat insulating material according to claim 2, wherein the heat storage material is sealed with a binder, and the binder is made of a resin or an inorganic compound.   In the gas barrier film, the core material and the heat storage material are respectively layered, and the core material layer and the heat storage material layer are laminated. The vacuum insulation material described.   The vacuum heat insulating material according to claim 6, which has a two-layer structure including the core material layer and the heat storage material layer in the gas barrier film.   The vacuum according to claim 6, wherein the gas barrier film has a three-layer structure including two core material layers and the heat storage material layer sandwiched between the two core material layers. Insulation.   The vacuum according to any one of claims 1 to 5, wherein the core material forms a layer, and the heat storage material covers 70% or more of the area of one surface of the core material layer. Insulation.   The vacuum heat insulating material of any one of Claims 1-9 containing the said heat storage material of less than 80 mass% with respect to the total mass of a vacuum heat insulating material.   The vacuum heat insulating material of any one of Claims 1-10 whose latent heat temperature of the said thermal storage material is -60-100 degreeC.   The vacuum heat insulating material according to any one of claims 1 to 11, wherein a latent heat amount of the heat storage material is 60 to 350 J / g.   The heat storage material is selected from the group consisting of calcium chloride hydrate, sodium sulfate hydrate, sodium thiosulfate hydrate, sodium acetate hydrate, vanadium oxide, paraffin, erythritol, and mixtures thereof. The vacuum heat insulating material of any one of 1-12.   The heat insulation box containing the vacuum heat insulating material of any one of Claims 1-13.   The heat insulating box including the vacuum heat insulating material according to claim 7 for keeping the inside of the box at a lower temperature than the outside, wherein the heat storage material layer is disposed on the inside of the box.   It is a heat insulation box containing the vacuum heat insulating material of Claim 8 for keeping the inside of a box at a low temperature from the outside, Comprising: The layer of the said heat storage material is arrange | positioned in the center of the thickness direction of the said vacuum heat insulating material. Or the heat insulating box disposed on the inner side of the box than the center.   It is a heat insulation box containing the vacuum heat insulating material of Claim 7 for maintaining the inside of a box at a temperature higher than the exterior, Comprising: The said heat storage material layer has arrange | positioned the said heat storage material layer on the box outer side.   It is a heat insulation box containing the vacuum heat insulating material of Claim 8 for maintaining the inside of a box at a temperature higher than the exterior, Comprising: The layer of the said thermal storage material is arrange | positioned in the center of the thickness direction of the said vacuum heat insulating material. Or the heat insulating box disposed on the outside of the box from the center.

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