JP2020176677A - Outer wrapping material for vacuum heat insulation material, vacuum heat insulation material, and article with vacuum heat insulation material - Google Patents

Abstract

To provide an outer wrapping material for vacuum heat insulation material capable of suppressing deterioration in heat insulation performance of a vacuum heat insulation material for a long time even under a high-temperature and high-humidity environment, and provide the vacuum heat insulation material employing the same, and an article with vacuum heat insulation material.SOLUTION: The present invention relates to an outer wrapping material 10 for vacuum heat insulation material. In a state where second principal surfaces of films 1 capable of thermally depositing two same outer wrapping materials for vacuum heat insulation material are stuck together, when a value of a loss tangent tanδ in an initial state of temperature 70°C and humidity 10%RH is defined as A, a value of the loss tangent tanδ in a humidified state of temperature 70°C and humidity 90%RH just after humidification of 5%RH/min from the initial state is defined as B, and a value of the loss tangent tanδ in a high humidity kept state where a condition of temperature 70°C and humidity 90%RH is kept for 1 hour is defined as C, in the outer wrapping material for vacuum heat insulation material, B/A which is a rate of change in the humidified state of the loss tangent tanδ is equal to or greater than 1.0 and equal to or smaller than 1.5 and C/B which is a rate of change in the high humidity kept state of the loss tangent tanδ is equal to or greater than 0.8 and equal to or smaller than 1.2.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to an outer packaging material for a vacuum heat insulating material, a vacuum heat insulating material, and an article with the vacuum heat insulating material capable of forming the vacuum heat insulating material.

In recent years, vacuum heat insulating materials have been used for the purpose of energy saving of articles. The vacuum heat insulating material is a member in which the core material is arranged inside the bag of the outer packaging material and the inside of the bag is held in a vacuum state where the pressure is lower than the atmospheric pressure, and the internal heat convection is suppressed, which is good. Can demonstrate excellent heat insulation performance. The outer packaging material used for the vacuum heat insulating material will be described as an outer packaging material for the vacuum heat insulating material, or simply an outer packaging material.

The outer packaging material for the vacuum heat insulating material has gas barrier performance to suppress the permeation of gas such as oxygen and steam in order to maintain the vacuum state inside the vacuum heat insulating material for a long period of time, and the ends are joined when wrapping the core material. Therefore, physical properties such as heat-welding property for sealing and sealing the core material are required. In order to satisfy these physical properties, the outer packaging material is generally configured to include a gas barrier layer and a heat-weldable film as members (Patent Documents 1 to 4). Examples of the gas barrier layer include a metal foil having a thickness of several μm to several tens of μm, a gas barrier film having a thickness of several nm to several hundred nm on one side or both sides of a resin base material, and having a gas barrier film containing an inorganic substance. Is used.

Among the gas barrier layers, the gas barrier film in particular can exhibit high gas barrier performance even if it is thin, and heat bridging is unlikely to occur. Further, since the gas barrier film has better flexibility than the metal foil, defects are less likely to occur when the vacuum heat insulating material is formed, and the gas barrier performance is less likely to be deteriorated due to the occurrence of defects. Therefore, the gas barrier film is being adopted as a gas barrier layer for the outer packaging material for vacuum heat insulating materials.

Japanese Unexamined Patent Publication No. 2003-262296 Japanese Unexamined Patent Publication No. 2013-103343 Japanese Unexamined Patent Publication No. 2006-70923 Japanese Unexamined Patent Publication No. 2014-62562

However, the general vacuum heat insulating outer packaging material behaves differently when used in a high temperature and high humidity environment for a long period of time than when used in a high temperature and dry environment due to the influence of water content of the base material, and the barrier performance deteriorates. In some cases, it may be difficult to maintain the heat insulating performance for a long period of time in a high temperature and high humidity environment.

The present disclosure includes an outer packaging material for a vacuum heat insulating material that can suppress deterioration of the heat insulating performance of the vacuum heat insulating material for a long period of time even in a high temperature and high humidity environment, and a vacuum heat insulating material and a vacuum heat insulating material using the same. The main purpose is to provide goods.

The present disclosure includes a heat-weldable film and a resin base material located on the first main surface side of the heat-weldable film and a gas barrier film arranged on one or both sides of the resin base material. The outer packaging material for a vacuum heat insulating material having the above gas barrier layer and the above-mentioned outer packaging material for a vacuum heat insulating material is the second main component of the film capable of heat-welding two identical outer packaging materials for the vacuum heat insulating material. With the surfaces bonded together, the loss tangent tan δ was measured by dynamic viscoelasticity measurement at a frequency of 10 Hz, and the value of the loss tangent tan δ in the initial state at a temperature of 70 ° C. and a humidity of 10% RH was A, and 5 from the initial state. The value of the loss positive contact tan δ in the humidified state immediately after humidifying to a temperature of 70 ° C. and a humidity of 90% RH at% RH / min is B, and the loss positive contact in a high humidity holding state in which the temperature of 70 ° C. and humidity of 90% RH are maintained for 1 hour. When the value of tan δ is C, the B / A, which is the rate of change of the loss tangent tan δ during humidification, is 1.0 or more and 1.5 or less, and the rate of change of the loss tangent tan δ during high humidity retention. Provided is an outer packaging material for a vacuum heat insulating material having a C / B of 0.8 or more and 1.2 or less.

Further, the present disclosure provides a vacuum heat insulating material having a core material and an outer packaging material in which the core material is enclosed, wherein the outer packaging material is the above-mentioned vacuum heat insulating outer packaging material. ..

Further, the present disclosure is an article having a heat insulating region and an article with a vacuum heat insulating material provided with the vacuum heat insulating material, and the vacuum heat insulating material has a core material and an outer packaging material in which the core material is enclosed. Provided is an article with a vacuum heat insulating material, wherein the outer packaging material is the above-mentioned vacuum heat insulating outer packaging material.

According to the present disclosure, it is possible to provide an outer packaging material for a vacuum heat insulating material that can maintain the heat insulating performance of the vacuum heat insulating material for a long period of time even in a high temperature and high humidity environment.

It is the schematic sectional drawing which shows an example of the external packaging material for a vacuum heat insulating material of this disclosure. It is a schematic perspective view and sectional view which shows an example of the vacuum heat insulating material of this disclosure. This is a temperature / humidity program for obtaining the rate of change during humidification and the rate of change during high humidity retention of the loss tangent tan δ in the present disclosure. It is the schematic of the film forming apparatus used in an Example. It is the schematic of the plasma pretreatment mechanism of the film forming apparatus used in an Example. It is the schematic of the film forming mechanism of the film forming apparatus used in an Example.

The present disclosure includes an outer packaging material for a vacuum heat insulating material, a vacuum heat insulating material, and an article with the vacuum heat insulating material in embodiments. Hereinafter, embodiments of the present disclosure will be described with reference to drawings and the like. However, the present disclosure can be implemented in many different embodiments and is not construed as limited to the description of the embodiments exemplified below. Further, in order to clarify the explanation, the drawings may schematically represent the width, thickness, shape, etc. of each part as compared with the embodiment, but this is merely an example and the interpretation of the present disclosure is limited. It's not something to do. Further, in the present specification and each figure, the same elements as those described above with respect to the above-mentioned figures may be designated by the same reference numerals, and detailed description thereof may be omitted as appropriate. Further, for convenience of explanation, the phrase "upper" or "lower" may be used for explanation, but the vertical direction may be reversed.

Further, in the present specification, when a certain structure such as a certain member or a certain area is "above (or below)" another structure such as another member or another area, there is no particular limitation. As long as this includes not only the case of being directly above (or directly below) the other configuration, but also the case of being above (or below) the other configuration, that is, separately above (or below) the other configuration. Including the case where the component of is included.

In this specification, the loss tangent tan δ may be abbreviated as “tan δ”. Further, the "external packaging material for vacuum heat insulating material" may be abbreviated as "external packaging material".

As a result of diligent studies to solve the above problems, the present inventors have obtained the rate of change during humidification of the loss direct contact tan δ of two heat-weldable films of the vacuum heat insulating material outer packaging material bonded to each other facing each other. A certain B / A is 1.0 or more and 1.5 or less, and the C / B, which is the rate of change of the loss tangent tan δ during high humidity retention, is 0.8 or more and 1.2 or less. If so, it has been found that the heat insulating performance of the vacuum heat insulating material can be maintained for a long period of time in a high temperature and high humidity environment.

It is known that when the moisture in the surrounding environment penetrates into the resin material and adsorbs it, it gives a plasticizing effect, and the tangent tan δ curve shifts the glass transition to the low temperature side as the relative humidity rises, and the amount of water adsorbed on the resin material. The value of the loss tangent tan δ changes depending on. From this, when considering a laminated body consisting of a plurality of layers placed in a constant humidity environment, the layer not located on the outermost surface (existing inside the laminated body) has hygroscopicity and water vapor permeability of adjacent layers. It was estimated that the amount of water adsorbed would change depending on the nature of the water vapor.

In the present disclosure, the loss tangent tan δ is used as an index of the humidity in the outer packaging material for the vacuum heat insulating material, and the rate of change of the loss tangent tan δ at high temperature during humidification and the rate of change during holding at high temperature and high humidity satisfy the above ranges. That is, keeping the change in the value of the loss tangent tan δ low under both conditions means that the humidity inside the vacuum heat insulating material outer packaging material is low even when the vacuum heat insulating material outer packaging material is used in a high temperature and high humidity environment. It was found that it would be possible to do so. In this way, by suppressing the change in the value of the loss tangent tan δ under both conditions to be low, the outer packaging material for the vacuum heat insulating material of the present disclosure deteriorates the gas barrier layer due to exposure to a high humidity state, for example, metal aluminum is hydroxideed. It is presumed that it is possible to suppress chemical deterioration due to aluminum and physical deterioration due to expansion and contraction of the base material. This makes it possible to provide the outer packaging material for the vacuum heat insulating material which can maintain the heat insulating performance of the vacuum heat insulating material for a long period of time even when used in a high temperature and high humidity environment. ..

I. The outer packaging material for the vacuum heat insulating material The outer packaging material for the vacuum heat insulating material of the present disclosure includes a heat-weldable film and a resin base material and the resin base material located on the first main surface side of the heat-weldable film. An outer packaging material for a vacuum heat insulating material having one or more gas barrier layers having a gas barrier film arranged on one side or both sides, wherein the outer packaging material for the vacuum heat insulating material is two identical outer packaging materials for the vacuum heat insulating material. With the second main surfaces of the heat-weldable film bonded to each other, the loss positive contact tan δ was measured by dynamic viscoelasticity measurement at a frequency of 10 Hz, and the temperature was 70 ° C. and the humidity was 10% RH. The value of the loss positive tan δ is A, the value of the loss tang tan δ in the humidified state immediately after humidifying to a temperature of 70 ° C. and a humidity of 90% RH at 5% RH / min from the initial state is B, and the value of the loss positive tan δ is B, the temperature is 70 ° C. and the humidity is 90% RH. When the value of the loss positive contact tan δ at the time of holding the high temperature and high humidity for 1 hour is C, the B / A which is the rate of change of the loss positive contact tan δ during humidification is 1.0 or more and 1.5 or less, and The outer packaging material for vacuum heat insulating material has a C / B of 0.8 or more and 1.2 or less, which is the rate of change of the loss positive contact tan δ during high humidity retention.

FIG. 1 is a schematic cross-sectional view showing an example of the outer packaging material for a vacuum heat insulating material of the present disclosure, and has a heat-weldable film 1 and three gas barrier films 2A, 2B, and 2C. The gas barrier films 2A, 2B and 2C have gas barrier films 4A, 4B and 4C arranged on one surface side of the resin base materials 3A, 3B and 3C and the resin base materials 3A, 3B and 3C, respectively.

The outer packaging material 10 for a vacuum heat insulating material of the present disclosure has a frequency of 10 Hz in a state where the second main surfaces of the heat-weldable film 1 and the other outer packaging material 10 for a vacuum heat insulating material are bonded to each other so as to face each other. The value of the loss tangent tan δ obtained by the dynamic viscoelasticity measurement of A in the initial state of temperature 70 ° C. and humidity 10% RH is immediately after humidification to temperature 70 ° C. humidity 90% RH at 5% RH / min from the above initial state. When the value in the humidified state is B and the value in the high humidity holding state where the temperature is 70 ° C. and the humidity is 90% RH for 1 hour is C, the B / A which is the rate of change of the loss tangent tan δ in the humidified state and the above. The C / B, which is the rate of change of the loss tangent tan δ at high humidity, is within a predetermined range.

Hereinafter, the characteristics and composition of the outer packaging material in the present disclosure will be described.
A. Characteristics The outer packaging material for vacuum heat insulating material of the present disclosure has a B / A of 1.0 or more and 1.5 or less, which is the rate of change of the loss tangent tan δ during humidification, and the change of the loss tangent tan δ during high humidity retention. The C / B, which is the rate, is 0.8 or more and 1.2 or less.

The loss positive contact tan δ in the present disclosure is an outer packaging material laminate in which the outer packaging material for the vacuum heat insulating material is bonded to the second main surfaces of the heat-weldable film with the other same outer packaging material for the vacuum heat insulating material. It is the ratio of the loss elastic modulus E ”to the stored elastic modulus E ′ obtained by the dynamic viscoelasticity measurement at a frequency of 10 Hz.
Here, the sealing method and the conditions for bonding the above two outer packaging materials for the vacuum heat insulating material are not particularly limited, but using an impulse sealer (FA-600 manufactured by Fuji Impulse Co., Ltd.), the sealing width is 10 mm, and the heating time. It can be sealed under the conditions of 1.0 second and cooling time of 2.0 seconds.

The loss tangent tan δ of the outer packaging material is measured by collecting a measurement sample from the outer packaging material laminate in which the heat-weldable films are bonded to each other so that the seal width direction of the seal portion is in the lateral direction. can do. The measurement sample is preferably taken from each of the plurality of packaging material laminates sealed in different directions so that the measurement directions are in a plurality of directions (for example, eight directions), and the loss tangent tan δ is JIS K7244-4 :. The average of the values measured by the tensile method using a dynamic viscoelasticity measuring device based on the measurement conditions described later with reference to 1999 (Plastic-Dynamic Mechanical Properties Test Method Part 4: Tensile Vibration-Non-Resonant Method). It can be a value. As the dynamic viscoelasticity measuring device, for example, DVA-225 manufactured by IT Measurement Control can be used.

Then, the temperature and humidity program shown in FIG. 3 and the loss tangent tan δ are measured under the following conditions, and the loss tangent tan δ value is A in the initial state of temperature 70 ° C. and humidity 10% RH, and 5% RH / min from the above initial state. The value B in the humidified state immediately after humidifying to a temperature of 70 ° C. and a humidity of 90% RH, and the value C in a high humidity holding state in which the temperature of 70 ° C. and a humidity of 90% RH are maintained for 1 hour are measured. Each temperature for measuring the tensile storage elastic modulus can be tolerated within the range of ± 0.5 ° C. Further, the value A in the initial state of the temperature of 70 ° C. and the humidity of 10% RH can be the value after being held at the temperature of 70 ° C. and the humidity of 10% RH for 60 minutes. The value B immediately after humidifying to a temperature of 70 ° C. and a humidity of 90% RH is that after holding the product at a temperature of 70 ° C. and a humidity of 10% RH for 60 minutes, it was humidified to a temperature of 70 ° C. and a humidity of 90% RH at a humidification rate of 5% RH / min. After that, it can be the value after holding for 3 minutes. The value C when the temperature is 70 ° C and the humidity is 90% RH for 1 hour is the value C when the temperature is 70 ° C and the humidity is 10% RH for 60 minutes, and then the humidification rate is 5% RH / min and the temperature is 70 ° C and the humidity is 90%. It can be the value after humidifying the RH and holding it at that temperature and humidity for 60 minutes.
Next, B / A, which is the rate of change of the loss tangent tan δ during humidification, and C / B, which is the rate of change of the loss tangent tan δ during high humidity retention, are calculated.

<Measurement conditions for loss tangent tan δ value>
-Measurement sample: 20 mm (longitudinal direction) x 5 mm (short direction) rectangle-Chuck distance (chuck measurement sample length): 15 mm
-Measurement mode: Tensile method (sine wave strain tension mode)
・ Frequency: 10Hz
-Static load: 25.00 cN to 300.00 cN
-Strain amount: 7.00 μm to 7.60 μm
・ Static / power ratio: 1.5

In the present disclosure, the B / A, which is the rate of change of the loss tangent tan δ during humidification, is 1.0 or more and 1.5 or less, preferably 1.0 or more and 1.4 or less, and more preferably 1. It is 0 or more and 1.3 or less.
The C / B, which is the rate of change of the tangent tan δ at high humidity retention, is 0.8 or more and 1.2 or less, preferably 0.9 or more and 1.1 or less, and more preferably 0.93. It is 1.05 or less.

As long as the rate of change of the loss tangent tan δ during humidification and the rate of change during high humidity retention are within the above ranges, the value of the rate of change C / A of the loss tangent tan δ is not particularly limited, but can be, for example, 1.7 or less. It is preferably 0.8 or more and 1.4 or less, and more preferably 0.9 or more and 1.2 or less. With such a rate of change C / A of the loss tangent tan δ, it is possible to reliably maintain the heat insulating performance of the vacuum heat insulating material for a long period of time in a high temperature and high humidity environment.

B. Structure The constitution of the outer packaging material for the vacuum heat insulating material of the present disclosure comprises a heat-weldable film and one or both sides of a resin base material and the resin base material located on the first main surface side of the heat-weldable film. It is an outer packaging material for a vacuum heat insulating material having one or more gas barrier layers having a gas barrier film arranged in the above range, and the rate of change of the loss positive tan δ during humidification and the rate of change of the loss positive tan δ during high humidity holding are within the above ranges. As long as it satisfies, there is no particular limitation. The rate of change of the loss tangent tan δ during humidification and the rate of change of the loss tangent tan δ during high humidity retention vary depending on the composition of the gas barrier layer, the stacking order thereof, the composition of the heat-weldable film, and the like.
For example, in the present disclosure, the gas barrier layer and the heat-weldable film exemplified below have the change rate of the loss tangent tan δ during humidification and the change rate of the loss tangent tan δ during high humidity holding within the above range. It can be configured by selecting and combining to satisfy.

(1) Gas Barrier Layer The gas barrier layer in the outer packaging material for the vacuum heat insulating material of the present disclosure is arranged on one surface side (first main surface side) of the heat-weldable film. Here, the gas barrier layer in the present disclosure refers to a composite film having a resin base material and a gas barrier film arranged on at least one surface of the resin base material. The outer packaging material for the vacuum heat insulating material of the present disclosure may have one gas barrier layer, but preferably has two or more layers, particularly three or more layers.
Further, a material having three gas barrier layers in which the rate of change of the loss tangent tan δ during humidification and the rate of change of the loss tangent tan δ during high humidity retention satisfy the above ranges is also preferable in terms of production efficiency.

a. Gas Barrier Membrane In the outer packaging material for vacuum heat insulating material of the present disclosure, one or more gas barrier layers can exhibit gas barrier performance mainly by the gas barrier membrane. In the present disclosure, the gas barrier film is particularly provided as long as the rate of change of the loss tangent tan δ during humidification and the rate of change of the loss tangent tan δ during high humidity holding of the outer packaging material laminate in which the two outer packaging materials are superposed satisfy the above ranges. Not limited.
Examples of the gas barrier film in this embodiment include a metal film, an inorganic compound film, and an M—OP bond (where M indicates a metal atom, O indicates an oxygen atom, and P indicates phosphorus, which will be described in detail below. Examples thereof include a film having (indicating an atom), a film containing a polyvalent metal salt of a polycarboxylic acid-based polymer, and a mixed compound film containing a metal element, an oxygen element, and a hydrophilic group-containing resin.

(I) Metal film Examples of the metal constituting the metal film include metals such as metallic aluminum, stainless steel, titanium, nickel, iron, and copper, or alloys containing these.

The metal film may be a thin-film film formed by a thin-film deposition method, or may be a coat film formed by a coating method such as coating. In the case of a thin-film deposition film, it may be formed by single-film deposition or the like, or may be formed by multiple-time vapor deposition. The metal film can be formed by a conventionally known method such as a coating method, a vapor deposition method, or a pressure bonding method.

Above all, a thin-film deposition film is preferable from the viewpoint of high adhesion to a resin base material and high gas barrier performance. One gas barrier film may be a single film formed by single vapor deposition, or may be formed by multiple vapor deposition and have a laminated structure.

(Ii) Inorganic compound film Examples of the inorganic compound constituting the inorganic compound film include metal elements such as silicon, aluminum, magnesium, calcium, potassium, tin, sodium, titanium, boron, ittrium, zirconi, muserium, and zinc, or non-metal elements. Examples thereof include oxides of metal elements, nitrides of oxides, nitrides, carbides of oxides, and carbides of oxides. Specifically, silicon oxides such as SiO ₂ , aluminum oxides such as Al ₂ O ₃ , magnesium oxides, titanium oxides, tin oxides, silicon zinc alloy oxides, indium alloy oxides, and silicon nitrides. Examples thereof include aluminum nitride, titanium nitride, silicon oxide and zinc oxide. The inorganic compound may be used alone or may be used by mixing the above-mentioned materials in an arbitrary ratio.

The inorganic compound film may be a thin-film film formed by a thin-film deposition method, or may be a coat film formed by a coating method such as coating. In the case of a thin-film deposition film, it may be formed by single-film deposition or the like, or may be formed by multiple-time vapor deposition. The inorganic compound film can be formed by a conventionally known method such as a coating method, a vapor deposition method, or a pressure bonding method.

Above all, a thin-film deposition film is preferable from the viewpoint of high adhesion to a resin base material and high gas barrier performance. One gas barrier film may be a single film formed by single vapor deposition, or may be formed by multiple vapor deposition and have a laminated structure.

(Iii) A film having an M-O-P bond As a film having an M-OP bond (where M represents a metal atom, O represents an oxygen atom, and P represents a phosphorus atom), For example, a film containing a reaction product of a metal oxide and a phosphorus compound can be mentioned.

Examples of the metal oxide include oxides of metals having a valence of 2 or more. Specifically, metals of Group 2 of the periodic table such as magnesium and calcium; Group 12 of the periodic table such as zinc. Metals; metals of Group 13 of the periodic table such as aluminum; metals of Group 14 of the periodic table such as silicon; oxides of metals such as transition metals such as titanium and zirconium. Of these, aluminum oxide (alumina) is preferable.

Examples of the phosphorus compound include phosphoric acid, polyphosphoric acid, phosphorous acid, phosphonic acid and derivatives thereof. Of these, phosphoric acid is preferable. Specific reaction products of metal oxides and phosphorus compounds can be, for example, the same as the reaction products disclosed in JP-A-2011-226644.

The presence of M-OP bonds causes the maximum infrared absorption peak to appear within the range of 1080 cm ^-1 or more and 1130 cm ^-1 or less in the infrared absorption spectrum (measured wavenumber range; 800 cm ^-1 or more and 1400 cm ^-1 or less). You can check it by doing. The method for measuring the infrared absorption spectrum is not particularly limited, and for example, a measurement method by the total reflection measurement method (ATR method), a method of scraping a sample from the gas barrier film of the outer packaging material, and measuring the infrared absorption spectrum by the KBr method. A measurement method or the like can be used for the collected sample by microinfrared spectroscopy.

(Iv) A film containing a polyvalent metal salt of a polycarboxylic acid polymer The film containing a polyvalent metal salt of a polycarboxylic acid polymer is a crosslinked bond between the carboxyl groups of the polycarboxylic acid polymer by a polyvalent metal ion. Has. The polyvalent metal salt of the polycarboxylic acid-based polymer is a reaction product of the polycarboxylic acid-based polymer and the polyvalent metal compound.

The presence of polyvalent metal salt of a polycarboxylic acid polymer, in the range of ^{1490cm -1 ~1659cm} -1 in the infrared absorption spectrum may be confirmed by the appearance of the absorption peak having an absorption maximum in the vicinity of 1560 cm ^-1 .. The peak, a carboxyl group forming a polyvalent metal salt - which is the peak of C = O stretching vibration attributable to ^(-COO). Usually, salts of carboxyl groups (-COO ^-) C = O stretching vibration attributable to ^the infrared wave number range of 1490cm ^-1 ~1659cm -1, giving an absorption peak having an absorption maximum in the vicinity of 1560 cm ^-1. The infrared absorption spectrum can be measured by a transmission method, an ATR method (attenuated total reflection method), a KBr pellet method, a diffuse reflection method, a photoacoustic method (PAS method), or the like.

Examples of the polycarboxylic acid-based polymer include polymers having two or more carboxyl groups in the molecule, and examples thereof include carboxyl groups such as polyacrylic acid, polymethacrylic acid, polymaleic acid, polyitaconic acid, and acrylic acid-methacrylic acid copolymer. Examples thereof include homopolymers and copolymers of monomers having the above.

The polyvalent metal compound is not particularly limited as long as the carboxyl group of the polycarboxylic acid polymer can be crosslinked. For example, an alkaline earth metal, a metal of Group 8 of the periodic table, a metal of Group 11 of the periodic table, and a period table 12 Examples thereof include hydroxides, carbonates, and carboxylates of metals such as group metals and metals of Group 13 of the periodic table. Specifically, magnesium (Mg), calcium (Ca), barium (Ba), zinc (Zn), copper (Cu), cobalt (Co), nickel (Ni), aluminum (Al), iron (Fe), etc. Divalent or higher valent metals, oxides, hydroxides, halides, carbonates, phosphates, phosphates, hypophosphates, sulfates, sulfites and the like of these metals can be mentioned. At least one of these may be used, and only one of them may be used, or two or more thereof may be used in combination.

Examples of the polyvalent metal salt of the polycarboxylic acid polymer include zinc acrylate, zinc methacrylic acid, sodium acrylate, potassium acrylate, magnesium acrylate, calcium acrylate, aluminum acrylate, sodium methacrylate, and methacrylic acid. Examples thereof include potassium acetate, magnesium methacrylate, calcium methacrylate and the like.

The membrane containing the polyvalent metal salt of the polycarboxylic acid-based polymer may also contain a binder resin. As the binder resin, a hydrophilic binder or a hydrophobic binder can be used. Examples of the hydrophilic binder include polyvinyl alcohol, polyvinylpyrrolidone, methylcellulose, carboxymethylcellulose, hydroxyethylcellulose, hydroxypropylcell source, sodium alginate, ethylene-vinyl alcohol copolymer, starch, dextran, gelatin, and modified products thereof. , At least one selected from these groups can be used.

The film containing the polyvalent metal salt of the polycarboxylic acid polymer is, for example, coated with a barrier layer forming solution in which a carboxylic acid resin, a polyvalent metal compound and a binder resin are dissolved in a solvent, and irradiated with an electron beam. Can be formed. Further, the polycarboxylic acid-based polymer layer and the polycarboxylic acid-based compound-containing layer can be laminated adjacent to each other to form a film containing a polyvalent metal salt of the polycarboxylic acid-based polymer by an interlayer reaction.

(V) Mixed compound film containing a metal element, an oxygen element and a hydrophilic group-containing resin A mixed compound film containing a metal element, an oxygen element and a hydrophilic group-containing resin is a general formula R ¹ _n M (OR ² ) _m. (wherein, R1, ^{R 2} represents an organic group having 1 to 8 carbon atoms, M represents a metal atom, n is an integer of 0 or more, m represents an integer of 1 or more , N + m represents the valence of M.), Containing at least one kind of metal alkoxide represented by), a hydrophilic group-containing resin, and further containing a solgel compound obtained by polycondensation by the solgel method. It is a membrane. Hereinafter, a mixed compound film containing a metal element, an oxygen element, and a hydrophilic group-containing resin is referred to as a solgel compound film.

The solgel compound film may have a cross-linked C-OM bond via oxygen (O) between the carbon atom (C) in the hydrophilic group-containing resin and the metal atom (M) in the metal alkoxide. it can.

The metal alkoxide is represented by the general formula R ¹ _n M (OR ² ) _m , and may be a partial hydrolyzate of alkoxide, a hydrolyzate condensate of alkoxide, or the like. Examples of M include silicon, zirconium, titanium, and aluminum. Examples of R ¹ include methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, sec-butyl group, t-butyl group and n-hexyl group. Examples thereof include an n-octyl group. In addition, examples of R ² include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, a sec-butyl group, and the like. When a plurality of (OR ² ) are present in the same molecule, the (OR ² ) may be the same or different.

Among them, the metal alkoxide is preferably an alkoxysilane containing silicon. Alkoxysilanes include tetramethoxysilane Si (OCH ₃ ) ₄ , tetraethoxysilane Si (OC ₂ H ₅ ) ₄ , tetrapropoxysilane Si (OC ₃ H ₇ ) ₄ , and tetrabutoxysilane Si (OC ₄ H ₉ ) _4. And so on.

Hydrophilic group-containing resin, hydroxy (-OH), an carboxy group (-COOH), a amino _(-NH 2), carbonyl group (> CO), a sulfo group resin having a hydrophilic group _(-SO 3 H) or the like Is. Examples of the hydrophilic group-containing resin include polyvinyl alcohol resins and ethylene / vinyl alcohol copolymers. These may be used alone or in combination.

Examples of the sol-gel compound include a sol-gel compound containing Si, O, and PVA, which is a polycondensate of tetraethoxysilane (TEOS) and polyvinyl alcohol (PVA).

The sol-gel compound film is coated with, for example, a solution for forming a barrier layer prepared by mixing a metal alkoxide, a hydrophilic group-containing resin, a silane coupling agent, a sol-gel method catalyst, an acid, water, an organic solvent, etc., and after drying. It can be formed by performing heat treatment.

Other details of the sol-gel compound film not described in the present disclosure can be the same as those disclosed in, for example, Japanese Patent No. 5568897 and Japanese Patent Application Laid-Open No. 2017-61956.

(Vi) Others The thickness of the gas barrier film is desired for the entire outer packaging material, as the rate of change of the loss tangent tan δ during humidification and the rate of change of the loss tangent tan δ during high humidity retention of the two outer packaging materials overlapped with each other satisfy the above ranges. The gas barrier performance is not particularly limited as long as it can be exhibited, and can be appropriately set according to the type of the gas barrier film. The thickness of the gas barrier film can be, for example, 5 nm or more and 500 nm or less, particularly 10 nm or more and 400 nm or less, and particularly 20 nm or more and 300 nm or less. When the gas barrier film is a metal film or an inorganic compound film, the upper limit of the thickness of the gas barrier film can be further reduced. For example, the thickness of the metal film or the inorganic compound film is within the range of 5 nm or more and 200 nm or less, particularly. It can be in the range of 10 nm or more and 150 nm or less.

When the gas barrier film has a laminated structure, films having the same composition may be combined, or films having different compositions may be combined. When the gas barrier film has a laminated structure, the entire multilayer film constituting the laminated structure is equivalent to one gas barrier film.

When one gas barrier membrane has a laminated structure, the thickness of the gas barrier membrane means the thickness of the entire laminated structure of one gas barrier membrane. If the thickness of the gas barrier film is less than the above range, the film formation may be insufficient and the desired gas barrier performance may not be exhibited. In addition, strength may not be ensured and deterioration may occur over time. On the other hand, if the thickness of the gas barrier film exceeds the above range, defects may easily occur when a mechanical stress such as bending is applied, or the flexibility may decrease. In addition, the content of inorganic substances in the entire outer packaging material may become excessive, and heat bridging may easily occur in the vacuum heat insulating material.

The gas barrier film may be arranged on at least one side of the resin base material, and may be arranged on both sides of the resin base material.

The method for forming the gas barrier film may be any method as long as it can form a film with a desired thickness on one side or both sides of the resin base material, and conventionally known methods such as a coating method, a thin film deposition method, a pressure bonding method, etc. Can be used.

b. Resin base material As the resin constituting the resin base material, the rate of change of the loss tangent tan δ during humidification and the rate of change of the loss tangent tan δ during high humidity retention of the two outer packaging materials overlapped with each other satisfy the above ranges, and the gas barrier film. Is not particularly limited as long as it can support the above, and examples thereof include known resins used for gas barrier films. Specifically, the above resins include polyolefin resins, polyester resins, cyclic polyolefin resins, polystyrene resins, polyvinyl chloride resins, acrylonitrile-styrene copolymer (AS) resins, acrylonitrile-butadiene-styrene copolymer (ABS) resins, and the like. Examples thereof include polymethylmethacrylate (PMMA) resin, polycarbonate resin, polyvinyl alcohol-based resin, ethylene-vinyl ester copolymer saponified product, polyamide resin such as various nylons, polyimide resin, polyurethane resin, acetal resin, cellulose resin and the like. The resin base material can contain one or more of the above-mentioned various resins.

The resin base material can be a resin film containing at least one selected from the above-mentioned resin group as a main component. The resin film may be unstretched or may be uniaxially or biaxially stretched. Further, the resin base material may or may not have transparency.

Here, the main component means that a predetermined resin is contained to such an extent that the above-mentioned characteristics after high temperature and high humidity retention are satisfied. Specifically, the content of the above-mentioned predetermined resin in the resin film is preferably 50% by mass or more, particularly preferably 90% by mass or more, and in particular, the resin film is composed of only the predetermined resin. Is preferable. When two or more resins of the same type are contained, the principal component means that the total sum of two or more resins of the same type is within the above range. Specifically, when the resin film contains two types of polyester resins, polyethylene terephthalate resin and polybutylene terephthalate resin, the fact that the resin film contains polyester resin as a main component means that the polyethylene terephthalate resin and poly in the resin film. It means that the total content of the butylene terephthalate resin is within the above-mentioned range. The same applies to resins other than polyester resins.

That is, as the resin film that can be suitably used as the above resin base material, polyester resin film, polypropylene resin film, cyclic polyolefin resin film, polyimide resin film, polyvinyl chloride resin film, polystyrene resin film, polymethylmethacrylate resin Examples thereof include a film, a polycarbonate resin film, an acrylonitrile-styrene copolymer film, and an acrylonitrile-butadiene-styrene copolymer film. Above all, the polyester resin film has low hygroscopicity, and is preferable in that the rate of change of the loss tangent tan δ during humidification and the rate of change of the loss tangent tan δ during high humidity retention are within the above ranges. Further, the polyester resin film has low elasticity due to heat and is relatively inexpensive.

The resin base material may contain additives. Examples of the additive include lubricants, cross-linking agents, antioxidants, ultraviolet absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments, and modifying resins. Further, the resin base material may be surface-treated. This is because the adhesion with the gas barrier film can be improved.

The thickness of the resin base material is not particularly limited as long as it can support the gas barrier film, but can be, for example, in the range of 6 μm or more and 200 μm or less, preferably in the range of 9 μm or more and 100 μm or less.

(2) Heat-weldable film The heat-weldable film in the vacuum heat insulating material outer packaging material of this embodiment is located on the outermost side of the vacuum heat insulating material outer packaging material in the thickness direction and bears the outermost surface of the other. Is. The heat-weldable film is in contact with the core material when the vacuum heat insulating material is produced using the outer packaging material for the vacuum heat insulating material, and when the core material is sealed, a pair of facing each other via the core material. It is a member that joins the peripheral edges of the outer packaging material for vacuum heat insulating material by heat welding.

For the heat-weldable film, a material that is melted by heating and can be welded is used. As such a material, a thermoplastic resin is preferably used. Examples of the thermoplastic resin include polyolefin resins, polyester resins, polyvinyl acetate resins, polyvinyl chloride resins, poly (meth) acrylic resins, urethane resins, polyvinyl alcohol resins, and ethylene-vinyl alcohol copolymers. Examples thereof include a film containing (EVOH) resin, polyphenylene sulfide (PPS) resin, tetrafluoroethylene (C ₂ F ₄ ) / ethylene (C ₂ H ₄ ) copolymer (ETFE) resin as a main component.

The heat-weldable film is preferably a film containing the above-mentioned thermoplastic resin as a main component. Specifically, polyethylene such as linear short chain branched polyethylene (LLDPE) and high density polyethylene (HDPE), polyolefin resin film such as unstretched polypropylene (CPP), polyethylene terephthalate (PET), polyethylene naphthalate (PEN). ), Polybutylene terephthalate (PBT) and other polyester resin films, polyvinyl acetate resin films, polyvinyl chloride resin films, poly (meth) acrylic resin films, urethane resin films, polyvinyl alcohol resin films, ethylene- Examples thereof include vinyl alcohol copolymer (EVOH) resin film, polyphenylene sulfide (PPS) resin film, tetrafluoroethylene (C ₂ F ₄ ) and ethylene (C ₂ H ₄ ) copolymer (ETFE) resin film. The main component refers to a component that accounts for 50% by mass or more of the heat-weldable film.

The heat-weldable film can be appropriately selected from the above resin films according to the melting point to be set. For example, a resin film containing a low melting point resin such as linear short chain branched polyethylene (LLDPE) as a main component has high versatility, and the melting point of a heat-weldable film can be set low, so that the temperature is relatively low. From the viewpoint of heat welding in the above, it can be preferably used. Further, for resin films mainly composed of resins having a melting point of 145 ° C. or higher, such as PP resin, EVOH resin, PET resin, PBT resin, ETFE resin, and PPS resin, the melting point of the heat-welable film is set to 145 ° C. or higher. It can be preferably used from the viewpoint of being able to prevent thermal deterioration of the heat-weldable film and obtaining a vacuum heat insulating material that can withstand use in a higher temperature environment.

The heat-weldable film may contain other materials such as an anti-blocking agent, a lubricant, a flame retardant, and a filler in addition to the above-mentioned resin.

The melting point of the heat-weldable film depends on the material, but is preferably 50 ° C. or higher, more preferably 80 ° C. or higher, more preferably 100 ° C. or higher, and particularly preferably 145 ° C. or higher. The melting point is preferably 300 ° C. or lower, more preferably 290 ° C. or lower, and more preferably 280 ° C. or lower. By setting the melting point of the heat-weldable film within the above range, it is possible to suppress the peeling of the sealing surface of the outer packaging material under the usage environment of the vacuum heat insulating material manufactured by using the outer packaging material of the present disclosure. It can withstand use in a high temperature environment. Further, when the vacuum heat insulating material is manufactured using the outer packaging material of the present disclosure, thermal deterioration of the gas barrier film or the heat-weldable film can be suppressed by heating for sealing. Further, the heat-weldable film can be made difficult to expand or shrink even when used in a high temperature environment for a long period of time by increasing the melting point.

The melting point of the heat-weldable film in the outer packaging material of the present disclosure can be measured by the following method using a differential scanning calorimeter (DSC). First, the heat-weldable film is peeled off from the outer packaging material to obtain a measurement sample of about 10 mg. This measurement sample is placed in an aluminum cell, and the temperature is raised from 20 ° C. to 300 ° C. at a heating rate of 10 ° C./min under a nitrogen atmosphere using a differential scanning calorimeter (DSC204 manufactured by NETZSCH). Hold for 10 minutes. Further, the temperature is cooled to 20 ° C. at a temperature lowering rate of 10 ° C./min, held at that temperature for 10 minutes, and then raised again to 300 ° C. at a temperature rising rate of 10 ° C./min (second temperature rise). The intersection of the tangent line at the melting point observed at the time of the second temperature rise and the baseline of the DSC curve on the lower temperature side than the melting point can be set as the melting point of the heat-weldable film.

The thickness of the heat-weldable film is not particularly limited, but is, for example, within the range of 15 μm or more and 100 μm or less, preferably within the range of 25 μm or more and 90 μm or less, and more preferably within the range of 30 μm or more and 80 μm or less. be able to. By setting the thickness of the heat-weldable film within the above range, it is possible to suppress a decrease in the gas barrier property of the outer packaging material, and it is desirable when joining the two outer packaging materials in the production of the vacuum heat insulating material. Adhesive strength can be obtained.

C. Arbitrary Configuration The outer packaging material for vacuum heat insulating material of the present disclosure has a heat-weldable film on one outermost side in the thickness direction, but a protective film is further placed on the outermost gas barrier layer located on the opposite side. Can have. By having the protective film, the outer packaging material for the vacuum heat insulating material can be protected from damage and deterioration. As the protective film, a general-purpose resin film having a higher melting point than a heat-weldable film can be used, and examples thereof include a nylon film, a polyethylene terephthalate film, a polybutylene terephthalate film, and a polypropylene film. The thickness of the protective film is not particularly limited and can be set as appropriate.

The outer packaging material for the vacuum heat insulating material of the present disclosure may have an adhesive layer. The adhesive layer can be located, for example, between a heat-weldable film and a gas barrier layer, between two gas barrier layers, between a gas barrier layer and a protective film, and the like. As the material of the adhesive layer, conventionally known pressure-sensitive adhesives, thermoplastic adhesives, curable adhesives and the like can be used.

D. Preferred Embodiment As a preferred embodiment of the present disclosure, a mode in which a gas barrier layer having high water vapor barrier performance is arranged on the outermost side opposite to the heat-weldable film of the outer packaging material for the vacuum heat insulating material (first embodiment), described above. A mode in which a resin layer having a resin material having low hygroscopicity is used for the vacuum heat insulating material outer packaging material (second embodiment), a mode in which the resin base material of at least one gas barrier layer contains a desiccant, and the like (third embodiment). Can be mentioned.

1. 1. First Embodiment The first embodiment of the vacuum heat insulating material outer packaging material of the present disclosure is the vacuum heat insulating material outer packaging material having two or more gas barrier layers, and the vacuum heat insulating material among the two or more gas barrier layers. It is an embodiment in which the gas barrier layer arranged at the farthest position from the heat-welable film of the heat-weldable material of the external capsule material has the highest water vapor barrier property.
Hereinafter, the details of the outer packaging material for the vacuum heat insulating material of this embodiment will be described.

In this embodiment, when the outer packaging material for the vacuum heat insulating material has two or more gas barrier layers, the water vapor barrier performance is exhibited at the position farthest from the heat-welable film in the outer packaging material among the two or more gas barrier layers. Place the tall one. By arranging the gas barrier layer with high water vapor barrier performance on the outside air side in this way, it is possible to suppress the rise in humidity inside the outer packaging material when used in a high temperature and high humidity environment, and the change in the loss tangent tan δ during humidification. Rate and loss The rate of change of the tangent tan δ during high humidity retention can be within the above range. This is to keep the humidity inside the outer packaging material low, and finally, deterioration of the gas barrier film in the outer packaging material can be suppressed.

Here, the gas barrier layer having high water vapor barrier performance means that when the outer packaging material has two or more gas barrier layers, it has the highest water vapor barrier property among them. The water vapor permeability of such a gas barrier layer having high water vapor barrier performance is, for example, 0.5 g / (m ² · day) or less, and more preferably 0.2 g / (m ² · day) or less, particularly. , 0.1 g / (m ² · day) or less.

The measurement of the water vapor permeability of the gas barrier layer is based on JIS K7129: 2008 (Appendix B: infrared sensor method, the same shall apply hereinafter), using a water vapor permeability measuring device, temperature 40 ° C., relative humidity difference. It can be measured under the condition of 90% RH. As the water vapor permeability measuring device, for example, "PERMATRAN" manufactured by MOCON, USA can be used.

As the gas barrier film of the gas barrier layer, the resin base material, the heat-weldable film, and the like in this embodiment, those described in the above section "B. Composition" can be appropriately selected and used.

2. Second Embodiment The second embodiment of the outer packaging material for the vacuum heat insulating material of the present disclosure is an embodiment in which a resin layer having a resin material having low hygroscopicity is used for the outer packaging material of the vacuum heat insulating material. Here, examples of the resin layer include a resin base material of a gas barrier layer, a heat-weldable film, and the above-mentioned protective film which is arranged on the outermost air side when used as a vacuum heat insulating material.

By using a resin layer made of a material having low hygroscopicity in this way, it is possible to suppress an increase in the humidity inside the outer packaging material even when the vacuum heat insulating material is used in a high temperature and high humidity environment. It is possible, and the rate of change of the loss tangent tan δ during humidification and the rate of change of the loss tangent tan δ during high humidity retention can be within the above ranges. As a result, deterioration of the gas barrier film can be finally suppressed.

As a material having low hygroscopicity that can be used for the resin base material, a hydrophobic resin can be used. This is because the water absorption is low, so that the value of the loss tangent tan δ can be surely within the above range.

Specific examples of the hydrophobic resin include polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene resins, polypropylene resins, cyclic polyolefin resins, polyimide resins, polyvinyl chloride resins, polystyrene resins, and polymethyl methacrylates. Examples thereof include resins, polypropylene resins, acrylonitrile-styrene copolymers, and acrylonitrile-butadiene-styrene copolymers.
In the present disclosure, polyester resin is preferable, and PET is particularly preferable.

The resin base material can be a resin film containing at least one selected from the above-mentioned resin group as a main component. The resin film may be unstretched or may be uniaxially or biaxially stretched. Further, the resin base material may or may not have transparency.
In this embodiment, a resin having low hygroscopicity may be used for the resin base material in at least one gas barrier layer, but preferably, a resin having low hygroscopicity is used for the resin base material in all the gas barrier layers. Is preferable.

Further, as a material having low hygroscopicity that can be used for a heat-weldable film, a polyolefin resin can be mentioned, and specifically, polyethylene or polypropylene can be mentioned.
In the present disclosure, it is preferable that 50% or more, preferably 70% or more of the total film thickness of the outer packaging material is composed of a layer having the above-mentioned material having low hygroscopicity.

3. 3. Third Embodiment The third embodiment of the outer packaging material for the vacuum heat insulating material of the present disclosure is an embodiment in which at least one layer constituting the outer packaging material is a layer containing a desiccant. By having the outer packaging material having a layer containing a desiccant in this way, it is possible to reduce the humidity inside the outer packaging material, and the rate of change of the loss tangent tan δ during humidification and the rate of change of the loss tangent tan δ during high humidity retention can be determined. It can be within the above range, and finally it is possible to prevent deterioration of the gas barrier film.

Examples of such a desiccant include silica gel, zeolite, magnesium oxide, aluminum oxide, calcium oxide, barium oxide, phosphorus oxide, lithium chloride, calcium chloride, magnesium sulfate, montmorillonite and the like.
The layer containing the desiccant is not particularly limited as long as it is a layer containing the desiccant, but for example, zeolite, calcium oxide, or the like having a hygroscopic function is melted in a binder resin such as polyolefin or polyester. By kneading and forming a film, a layer in which the desiccant is dispersed can be obtained. Specifically, the films described in Moist Catch (registered trademark) (manufactured by Kyodo Printing Co., Ltd.), Dry Keep (manufactured by Sasaki Chemicals Co., Ltd.), JP-A-2017-12975, JP-A-8-217913, etc. Can be mentioned.

E. Others The thickness of the outer packaging material of the present disclosure is not particularly limited as long as it can have the above-mentioned characteristics, and can be, for example, in the range of 30 μm or more and 200 μm or less, preferably in the range of 50 μm or more and 150 μm or less.

Outer cover material of the present disclosure is preferably a water vapor transmission rate is 0.5g ^/ (m 2 · day) or less, preferably 0.1g ^/ (m 2 · day) or less, particularly 0.05 g / ^{(m 2} -Day) or less is preferable. This is because the outer packaging material of the present disclosure can form a vacuum heat insulating material having high water vapor barrier performance and high heat insulating performance when the water vapor permeability is within the above range.

The water vapor permeability of the outer packaging material can be measured by the following method.
The initial water vapor permeability can be measured in accordance with ISO 15106-5: 2015 (differential pressure method) under the conditions of a temperature of 40 ° C. and a relative humidity difference of 90% RH using a water vapor permeability measuring device. The water vapor permeability can be measured by the following procedure. First, a sample of an outer packaging material cut to a desired size is sampled, and among the outermost surfaces facing each other in the thickness direction (lamination direction), the outermost surface layer located on the opposite side of the heat-weldable film, which is one of the outermost layers, is formed. It is mounted between the upper and lower chambers of the above device so that it is on the high humidity side (water vapor supply side), and has a permeation area of about 50 cm ² (permeation area: circular with a diameter of 8 cm), a temperature of 40 ° C, and a relative humidity. The measurement is performed under the condition of a difference of 90% RH. As the water vapor permeability measuring device, for example, "DELTAPERM" manufactured by Technolux of the United Kingdom can be used.

Examples of the method for producing the outer packaging material of the present disclosure include a method in which each film produced in advance is bonded via the above-mentioned adhesive layer. Further, the outer packaging material of the present disclosure may be produced by sequentially extruding and laminating the raw materials of the heat-melted films with a T-die or the like.

The outer packaging material of the present disclosure can be used as a vacuum heat insulating material. In the vacuum heat insulating material, the outer packaging material of the present disclosure can be used by arranging the heat-weldable film so as to be on the core material side and facing each other via the core material.

II. Vacuum heat insulating material The vacuum heat insulating material of the present disclosure is a vacuum heat insulating material having a core material and an outer packaging material for encapsulating the core material, and the outer packaging material is the above-mentioned "I. Outer packaging material for vacuum heat insulating material". It is characterized in that it is the one explained in the section.

FIG. 2 is a schematic cross-sectional view showing an example of the vacuum heat insulating material of the present disclosure. The vacuum heat insulating material 20 illustrated in FIG. 2 has a core material 11 and an outer packaging material 10 for enclosing the core material 11, and the outer packaging material 10 is the outer packaging material for the vacuum heat insulating material described in FIG. The vacuum heat insulating material 20 is a bag body in which two outer packaging materials 10 face each other so that the heat-weldable films face each other, and the end portions 12 are joined by heat welding. The core material 11 is sealed, and the inside of the bag body is depressurized.

According to the present disclosure, the outer packaging material that encloses the core material is the outer packaging material for the vacuum heat insulating material described in the above-mentioned "I. Outer packaging material for vacuum heat insulating material", and thus is long in a high temperature and high humidity environment. Good heat insulation performance can be maintained for a period of time.
Hereinafter, the vacuum heat insulating material of the present disclosure will be described for each configuration.

1. 1. Outer packaging material The outer packaging material in the present disclosure is a member that encloses the core material, and is the same as the outer packaging material for the vacuum heat insulating material described in the above-mentioned "I. Outer packaging material for vacuum heat insulating material". The description is omitted.

2. Core material The core material in the present disclosure is a member enclosed by an outer packaging material. It should be noted that "sealing" means that the bag is sealed inside a bag formed by using the outer packaging material.

The core material preferably has a low thermal conductivity. The core material has a porosity of 50% or more, especially 9
It can be a porous material of 0% or more.

As a material constituting the core material, powder, foam, fiber or the like can be used. The powder may be inorganic or organic, and for example, dry silica, wet silica, aggregated silica powder, conductive powder, calcium carbonate powder, pearlite, clay, talc and the like can be used. Among them, a mixture of dry silica and conductive powder is advantageous when used in a temperature range in which the internal pressure rises, because the decrease in heat insulating performance due to the rise in the internal pressure of the vacuum heat insulating material is small. Further, by adding a substance having a small infrared absorption rate such as titanium oxide, aluminum oxide, or indium-doped tin oxide to the above-mentioned material as a radiation suppressing material, the infrared absorption rate of the core material can be reduced.

As the foam, urethane foam, styrene foam, phenol foam and the like can be used. Of these, a foam that forms open cells is preferable.

The fibrous body may be an inorganic fiber or an organic fiber, but it is preferable to use an inorganic fiber from the viewpoint of heat insulating performance. Examples of such inorganic fibers include glass fibers such as glass wool and glass fiber, alumina fibers, silica-alumina fibers, silica fibers, ceramic fibers, and rock wool. These inorganic fibers are preferable in that they have low thermal conductivity and are easier to handle than powders.

As the core material, the above-mentioned materials may be used alone, or a composite material in which two or more kinds of materials are mixed may be used.

3. 3. Vacuum heat insulating material In the vacuum heat insulating material of the present disclosure, a core material is sealed inside the outer packaging material, and the inside is decompressed to be in a vacuum state. The degree of vacuum inside the vacuum heat insulating material is preferably 5 Pa or less, for example. This is because the heat conduction due to the convection of the air remaining inside can be lowered, and excellent heat insulating properties can be exhibited.

The lower the thermal conductivity of the vacuum heat insulating material, the more preferable. For example, the thermal conductivity (initial thermal conductivity) is preferably 5 mW / (mK) or less. This is because the vacuum heat insulating material is less likely to conduct heat to the outside and can exert a high heat insulating effect. Above all, the initial thermal conductivity is more preferably 4 mW / (mK) or less, and further preferably 3 mW / (mK) or less.

The thermal conductivity is based on JIS A1412-2: 1999 (Measurement method of thermal resistance and thermal conductivity of thermal insulation material-Part 2: Heat flow meter method (HFM method)), and a thermal conductivity measuring device is used. It can be a value measured by the thermal flow meter method. As the thermal conductivity measuring device, for example, a thermal conductivity measuring device Autolambda (product name: HC-074, manufactured by Eiko Seiki) can be used. The measurement is performed under the following conditions so that both main surfaces of the measurement sample (vacuum heat insulating material) face in the vertical direction. Before measuring the thermal conductivity, it is preferable to measure in advance whether the temperature of the measurement sample is equal to the measurement environment temperature by using a heat flow meter or the like. At least three samples are measured under one condition, and the average of those measurements is taken as the value of thermal conductivity under that condition.

(Measurement conditions for thermal conductivity)
-Measurement sample: width 29 cm ± 0.5 cm, length 30 cm ± 0.5 cm
・ Time required for steady test: 15 minutes or more ・ Standard plate type: EPS
・ Temperature of high temperature surface: 30 ℃
・ Temperature of low temperature surface: 10 ℃
-Average temperature of measurement sample: 20 ° C

Further, since the vacuum heat insulating material of the present disclosure uses the above-mentioned external packaging material, deterioration of the heat insulating performance is suppressed for a long period of time even in a high temperature and high humidity environment. For example, the thermal conductivity of the vacuum heat insulating material after 500 hours at a temperature of 70 ° C. and a humidity of 90% RH can be set to 10 mW / (mK) or less.

4. Others As the method for producing the vacuum heat insulating material of the present disclosure, a general method can be used. For example, two sheets of the vacuum heat insulating material outer packaging material described in the above section "I. Vacuum heat insulating material outer packaging material" are prepared, and the heat-weldable films are overlapped with each other facing each other, and the outer edges of the three sides are overlapped. It is heat welded to obtain a bag body with one side open. A vacuum heat insulating material can be obtained by inserting a core material through the opening into the bag body, sucking air from the opening, and sealing the opening in a state where the inside of the bag body is depressurized.

The vacuum heat insulating material of the present disclosure can be used for, for example, an article requiring thermal insulation. The above articles will be described later.

III. Article with vacuum heat insulating material The article with vacuum heat insulating material of the present disclosure is an article having a heat insulating region and an article with a vacuum heat insulating material provided with the vacuum heat insulating material, and the vacuum heat insulating material is enclosed in a core material and a core material. The outer packaging material is the outer packaging material for the vacuum heat insulating material described in the above-mentioned "I. Outer packaging material for vacuum heat insulating material".

According to the present disclosure, the vacuum heat insulating material used in the article is composed of the outer packaging material described in the section "I. Outer packaging material for vacuum heat insulating material", and the vacuum heat insulating material is used for a long period of time in a high temperature and high humidity environment. Since it is possible to exhibit good heat insulating performance, it is possible to achieve energy saving of an article in a high temperature and high humidity environment and an object in which the above article is used.

The vacuum heat insulating material in the present disclosure and the outer packaging material used therein have been described in detail in the sections "II. Vacuum heat insulating material" and "I. Outer packaging material for vacuum heat insulating material" described above, and thus the description thereof is omitted here. To do.

The article in the present disclosure has a heat insulating region. Here, the heat-insulated region is a region that is heat-insulated by the vacuum heat insulating material, for example, a region that is heat-retained or cooled, a region that surrounds a heat source or a cooling source, or a region that is isolated from a heat source or a cooling source. Is. These areas may be spaces or objects. Examples of the above-mentioned articles include electric devices such as refrigerators, freezers, warmers, and coolers, heat-retaining containers, cold-retaining containers, transport containers, containers, containers such as storage containers, water storage containers and water storage facilities that require heat retention, piping, and vehicles. , Vehicles such as aircraft and ships, buildings such as houses and warehouses, building materials such as wall materials, floor materials and doors.

The present disclosure is not limited to the above embodiments. The above embodiment is an example, and any object having substantially the same structure as the technical idea described in the claims of the present disclosure and exhibiting the same effect and effect is the present invention. Included in the technical scope of the disclosure.

Examples and comparative examples are shown below, and the present disclosure will be described in more detail.

[material]
The members constituting the outer packaging material for the vacuum heat insulating material of Examples and Comparative Examples are shown below and in Table 1.
The adhesives used in Examples and Comparative Examples are shown below.

(Element)
-Gas barrier film A: PET film in which a metallic aluminum (Al) film is vapor-deposited on one side (VM-PET1519 manufactured by Toray Film Processing Co., Ltd., thickness 12 μm, water vapor permeability 0.21 g / (m ² · day))

-Gas barrier film B: PET film in which a metallic aluminum (Al) film is vapor-deposited on one side (VM-PET1510 manufactured by Toray Film Processing Co., Ltd., thickness 12 μm, water vapor permeability 0.7 g / (m ² · day))

-Gas barrier film C: Manufactured by the following manufacturing method.
(Production method)
A PET film (Lumirror P60 manufactured by Toray Processing Film, thickness 12 μm) was set in the unwinding device of a continuous vacuum vapor deposition machine (TopMet manufactured by Applied Materials) as a base material, and vaporized on one side while running at a running speed of 300 m / min. Metallic aluminum was adhered and deposited (first vapor deposition) to form an intermediate film, which was then wound up. In the first vapor deposition, the aluminum wire is fed to the resistance heating part to melt it in a vacuum vapor deposition machine reduced to less than 1.0 × 10 ^-1 Pa, and vaporized metallic aluminum is adhered and deposited on one side of the running PET film. It was. At this time, the power supply value (deposited board power value) to the resistance heating unit was set in the range of 8.0 kW to 9.0 kW. The wound intermediate film was set in the unwinding device again, and while traveling at a traveling speed of 250 m / min, vaporized metallic aluminum was further adhered and deposited on the metallic aluminum adhering surface of the intermediate film (second vapor deposition). .. Through two thin-film deposition steps, a gas barrier film having a metallic aluminum film formed on one side of the PET film was obtained. Then, the obtained gas barrier film was wound up. In the second vapor deposition, metallic aluminum was adhered and deposited under the same conditions as in the first deposition except that the power supply value (deposited board power value) to the resistance heating part was set in the range of 8.0 kW to 8.5 kW, and the barrier film C was deposited. Got The thickness of the metal-aluminum film of the obtained gas barrier film was measured from a cross section using an investigative electron microscope (SU-8000 manufactured by Hitachi High-Tech) and found to be 144 nm.

The aluminum film thickness was measured as follows.
A sample was cut out from the gas barrier film to a desired size, and the outer circumference of the cut out sample was fixed with a cured resin (cold-embedded resin Epofix manufactured by Marumoto Struas). The fixed sample is cut in the thickness direction with a diamond knife to expose the cross section, and an image of the exposed cross section is acquired using a scanning electron microscope (SU-8000 manufactured by Hitachi High-Tech) at a magnification of about 100,000 times. Then, the film thickness was measured at three points at approximately equal intervals in the image. This operation was performed on three samples for each gas barrier film, and the average of a total of nine measured values was taken as the value of the thickness of the metallic aluminum film on each gas barrier film. The water vapor permeability was 0.06 g / (m ² · day).

-Gas barrier film D: Manufactured by the following manufacturing method.
(Production method)
As the base material 100, a plastic base material (manufactured by KOLON, product name “CB981”) having a thickness of 12 μm and containing polyethylene terephthalate (PET) as a material was prepared, and the plasma pretreatment mechanism 16B and the film formation shown in FIG. A plasma pretreatment step and a film forming step were performed using the film forming apparatus 15 having the mechanism 16C to obtain a gas barrier film D. FIG. 6 is a schematic view of the dotted line portion I of FIG. 5 including the plasma pretreatment mechanism. In FIG. 6, 18 is a raw material volatilization supply device for supplying plasma raw material gas, and P is plasma.

FIG. 7 is a schematic view of the dotted line portion II of FIG. 5 including the film forming mechanism. Specifically, in the film forming step, a vapor deposition film containing aluminum was formed by a vacuum vapor deposition method using the evaporation mechanism 24 in FIG. Specifically, after adjusting the pressure in the film forming chamber 17 in FIG. 5 to 1 Pa, an aluminum metal wire 61 is supplied into the boat 24b as a vapor deposition material, and a resistance heating type evaporation mechanism 24 is used. , The vaporized material in the boat 24b was heated and aluminum was evaporated so as to reach the surface of the base material, thereby forming a thin-film deposition film on the surface of the base material. By the above method, a plurality of laminated films having a base material and a vapor-deposited film were produced. The thickness of the vapor-deposited film of the produced laminated film was 13 nm. The water vapor permeability was 0.12 g / (m ² · day).
The specific conditions are as follows.

[Conditions for plasma pretreatment mechanism 16B]
Form of plasma pretreatment mechanism 16B: The form shown in FIG.
The voltage applied between the pretreatment roller 30 and the electrode portion 21 is 340 V.
Plasma raw material gas supplied by the plasma raw material gas supply unit 22: A mixed gas of argon (Ar) and oxygen (O ₂ ).
The plasma density between the pretreatment roller 30 and the electrode portion 21 is 144 W · sec / m ² .
Magnetic field forming unit 23: A permanent magnet of 1000 gauss.

[Conditions for film formation mechanism 16C]
A form of the plasma supply mechanism 50: a hollow cathode 51 shown in FIG. 4, an anode (not shown) facing the opening of the cavity of the hollow cathode 51 arranged on both sides in the width direction of the base material 100 when viewed from the boat 24b. It is a form having.
How to use the plasma supply mechanism 50: A plasma raw material gas was supplied to the cavity of the hollow cathode 51 and discharged to excite the plasma. This plasma was drawn between the surface of the base material 100 and the evaporation mechanism 24 by the opposing anodes.

-Gas barrier film E: Ethylene vinyl alcohol copolymer (EVOH) film with a metallic aluminum (Al) film deposited on one side (VMXL manufactured by Kuraray, thickness 12 μm, water vapor permeability 0.50 g / (m ² · day)) )

-Gas barrier film F: Manufactured by the following manufacturing method.
(Production method)
For the first vaporization, the power supply value (deposited board power value) to the resistance heating part in the vacuum vapor deposition machine is set in the range of 7.5 kW to 8.0 kW, and the PET film as a base material is run at a traveling speed of 440 m / min. However, vaporized metallic aluminum is adhered and deposited on one side, and for the second vapor deposition, the power supply value (deposited board power value) to the resistance heating part in the vacuum vapor deposition machine is in the range of 8.0 kW to 8.5 kW, and the traveling speed is 440 m. A gas barrier film F was obtained in the same manner as the gas barrier film C except that vaporized metallic aluminum was adhered and deposited on the metallic aluminum adhering surface of the intermediate film while running at / min. The thickness of the metal-aluminum film of the obtained gas barrier film was measured from a cross section using an investigative electron microscope (SU-8000 manufactured by Hitachi High-Tech) and found to be 134 nm. The water vapor permeability was 0.09 g / (m ² · day)).

・ Gas barrier film G:
Silicon oxide (thickness: 20 nm) is vapor-deposited on a 12 μm-thick polyethylene terephthalate (PET) substrate (PET-F, manufactured by Unitica Co., Ltd.), and the following composition for a barrier coating film is gravure-coated on the vapor-deposited film. After coating by the method, heat treatment was performed at 120 ° C., 140 ° C. and 150 ° C. for 20 seconds each to form a barrier coating film (thickness: 300 nm) as a barrier coat film. The water vapor permeability was 0.14 g / (m ² · day)).

・ Gas barrier film H:
Alumina oxide (thickness: 20 nm) is vapor-deposited on a 12 μm-thick polyethylene terephthalate (PET) substrate (PET-F, manufactured by Unitica Co., Ltd.), and the following composition for a barrier coating film is gravure-coated on the vapor-deposited film. After coating by the method, heat treatment was performed at 120 ° C., 140 ° C. and 150 ° C. for 20 seconds each to form a barrier coating film (thickness: 300 nm) as a barrier coat film. The water vapor permeability was 0.11 g / (m ² · day)).

(Preparation of composition for barrier coating film)
Solution A (mixed solution consisting of polyvinyl alcohol, isopropyl alcohol and ion-exchanged water) prepared according to the composition shown in Table 1 below, and solution B (tetraethoxysilane (TEOS), isopropyl alcohol, prepared in advance according to the composition shown in Table 1). A hydrolyzed solution consisting of hydrochloric acid and ion-exchanged water) was added and stirred to obtain a colorless and transparent barrier coating film composition by the sol-gel method.

-Heat-weldable film A: Linear low-density polyethylene film (HC-E manufactured by Mitsui Chemicals Tohcello Co., Ltd., thickness 50 μm)

[Example 1]
A vacuum heat insulating material in which the first layer is a gas barrier film C, the second layer is a gas barrier film B, the third layer is a gas barrier film B, and the fourth layer is a heat-weldable film A in order from one of the stacking directions. The external packaging material was obtained. In the outer packaging material of Example 1, the gas barrier film C of the first layer was arranged so that the metallic aluminum film was closer to the gas barrier film B of the second layer than the PET film. The gas barrier film B of the second layer was arranged so that the metallic aluminum film was closer to the gas barrier film B of the third layer than the PET film. The gas barrier film B of the third layer was arranged so that the metallic aluminum film was closer to the gas barrier film B of the second layer than the PET film.

Each of the first to fourth layers was joined with an adhesive layer. The adhesive is an adhesive containing Rock Paint's main agent RU-77T and curing agent H-7 (main agent: curing agent: ethyl acetate = 10: 1: 14).
) Was used to form an adhesive layer of about 3.5 μm by the gravure coating method.

[Example 2]
A vacuum heat insulating material in which the first layer is a gas barrier film D, the second layer is a gas barrier film D, the third layer is a gas barrier film E, and the fourth layer is a heat-weldable film A in order from one of the stacking directions. The external packaging material was obtained. In the outer packaging material of Example 2, the gas barrier film D of the first layer was arranged so that the metallic aluminum film was closer to the gas barrier film D of the second layer than the PET film. The gas barrier film D of the second layer was arranged so that the metallic aluminum film was closer to the gas barrier film E of the third layer than the PET film. The gas barrier film E of the third layer was arranged so that the metallic aluminum film was closer to the gas barrier film D of the second layer than the EVOH film.

Each of the first to fourth layers was joined with an adhesive layer. As the adhesive, the same adhesive as in Example 1 was used.

[Example 3]
A vacuum heat insulating material in which the first layer is a gas barrier film D, the second layer is a gas barrier film F, the third layer is a gas barrier film E, and the fourth layer is a heat-weldable film A in order from one of the stacking directions. The external packaging material was obtained. In the outer packaging material of Example 3, the gas barrier film D of the first layer was arranged so that the metallic aluminum film was closer to the gas barrier film F of the second layer than the PET film. The gas barrier film F of the second layer was arranged so that the metallic aluminum film was closer to the gas barrier film E of the third layer than the PET film. The gas barrier film E of the third layer was arranged so that the metallic aluminum film was closer to the gas barrier film F of the second layer than the EVOH film.

Each of the first to fourth layers was joined with an adhesive layer. As the adhesive, the same adhesive as in Example 1 was used.

[Example 4]
The first layer is the gas barrier film F, the second layer is the gas barrier film G, the third layer is the gas barrier film G, the fourth layer is the gas barrier film F, and the fifth layer is heat welded in order from one of the stacking directions. An outer packaging material for a vacuum heat insulating material, which is a possible film A, was obtained. In the outer packaging material of Example 4, the gas barrier film F of the first layer was arranged so that the metallic aluminum film was closer to the gas barrier film G of the second layer than the PET film. The gas barrier film G of the second layer was arranged so that the barrier coat film was closer to the gas barrier film G of the third layer than the PET film. The gas barrier film G of the third layer was arranged so that the barrier coat film was closer to the gas barrier film G of the second layer than the PET film. The gas barrier film F of the fourth layer was arranged so that the metallic aluminum film was closer to the gas barrier film G of the third layer than the PET film.

Each of the first to fifth layers was joined with an adhesive layer. As the adhesive, the same adhesive as in Example 1 was used.

[Example 5]
A vacuum heat insulating material in which the first layer is a gas barrier film H, the second layer is a gas barrier film D, the third layer is a gas barrier film E, and the fourth layer is a heat-weldable film A in order from one of the stacking directions. The external packaging material was obtained. In the outer packaging material of Example 5, the gas barrier film H of the first layer was arranged so that the barrier coat film was closer to the gas barrier film D of the second layer than the PET film. The gas barrier film D of the second layer was arranged so that the metallic aluminum film was closer to the gas barrier film E of the third layer than the PET film. The gas barrier film E of the third layer was arranged so that the metallic aluminum film was closer to the gas barrier film D of the second layer than the EVOH film.

Each of the first to fourth layers was joined with an adhesive layer. As the adhesive, the same adhesive as in Example 1 was used.

[Comparative Example 1]
A vacuum heat insulating material in which the first layer is a gas barrier film A, the second layer is a gas barrier film B, the third layer is a gas barrier film B, and the fourth layer is a heat-weldable film A in order from one of the stacking directions. The external packaging material was obtained. In the outer packaging material of Comparative Example 1, the gas barrier film A of the first layer was arranged so that the metallic aluminum film was closer to the gas barrier film B of the second layer than the PET film. The gas barrier film B of the second layer was arranged so that the metallic aluminum film was closer to the gas barrier film B of the third layer than the PET film. The gas barrier film B of the third layer was arranged so that the metallic aluminum film was closer to the gas barrier film B of the second layer than the PET film.

Each of the first to fourth layers was joined with an adhesive layer. As the adhesive, the same adhesive as in Example 1 was used.

[Comparative Example 2]
A vacuum heat insulating material in which the first layer is a gas barrier film B, the second layer is a gas barrier film B, the third layer is a gas barrier film B, and the fourth layer is a heat-weldable film A in order from one of the stacking directions. The external packaging material was obtained. In the outer packaging material of Comparative Example 2, the gas barrier film B of the first layer was arranged so that the metallic aluminum film was closer to the gas barrier film B of the second layer than the PET film. The gas barrier film B of the second layer was arranged so that the metallic aluminum film was closer to the gas barrier film B of the third layer than the PET film. The gas barrier film B of the third layer was arranged so that the metallic aluminum film was closer to the gas barrier film B of the second layer than the PET film.

Each of the first to fourth layers was joined with an adhesive layer. As the adhesive, the same adhesive as in Example 1 was used.

[Comparative Example 3]
A vacuum heat insulating material in which the first layer is a gas barrier film B, the second layer is a gas barrier film B, the third layer is a gas barrier film A, and the fourth layer is a heat-weldable film A in order from one of the stacking directions. The external packaging material was obtained. In the outer packaging material of Comparative Example 3, the gas barrier film B of the first layer was arranged so that the metallic aluminum film was closer to the gas barrier film B of the second layer than the PET film. The gas barrier film B of the second layer was arranged so that the metallic aluminum film was closer to the gas barrier film A of the third layer than the PET film. The gas barrier film A of the third layer was arranged so that the metallic aluminum film was closer to the gas barrier film B of the second layer than the PET film.

Each of the first to fourth layers was joined with an adhesive layer. As the adhesive, the same adhesive as in Example 1 was used.

[Water vapor permeability]
The water vapor permeability of the outer packaging material for the vacuum heat insulating material produced in Comparative Example 1 and Comparative Example 3 was determined by E.I. The measurement was carried out by using "DELTAPERM" manufactured by Technox of the United Kingdom by the method described in the other sections. The water vapor permeability of Comparative Example 1 was 8 × 10 ⁻² g / (m ² · day), and the water vapor permeability of Comparative Example 3 was 8 × 10 − ² g / (m ² · day).

[Sample preparation]
Prepare the two outer packaging materials for the vacuum heat insulating material, put the heat-weldable films A facing each other, and use an impulse sealer (FA-600 manufactured by Fuji Impulse Co., Ltd.) to seal with a heating time of 1.0 second. The film was sealed with a width of 10 mm and a cooling time of 2.0 seconds. A rectangular sample of 20 mm × 5 mm was taken out from the sealed portion of the outer packaging material for the vacuum heat insulating material after heat sealing. The sealing direction was changed so that the measurement directions were eight, and the outer packaging material for the vacuum heat insulating material was heat-sealed, and the measurement data was taken out from each sealed portion to prepare a total of eight measurement samples.

[Measurement of loss tangent tan δ]
Using a dynamic viscoelasticity measuring device (DVA-225 manufactured by IT Measurement Control), the loss in the initial state after holding for 60 minutes at a temperature of 70 ° C. and a humidity of 10% RH according to the temperature / humidity program shown in FIG. (A), the value of the loss tang tan δ (B) when the temperature and humidity are kept at the temperature and humidity for 3 minutes after humidifying to a temperature of 70 ° C. and a humidity of 90% RH at a humidification rate of 5% RH / min from the initial state, and then the temperature. The value (C) of the loss tangent tan δ when the humidity of 70 ° C. and humidity of 90% RH was maintained for 1 hour was measured. The measurement conditions are as follows. The loss tangent tan δ value was taken as the average value of the measured values of the eight measurement samples. The results are shown in Table 3.

-Measurement mode: Tensile method (sine wave strain tension mode)
・ Temperature rise rate: 5 ° C / min
・ Humidification rate: 5% RH / min
・ Frequency: 10Hz
-Measurement temperature: 70 ° C
-Measurement humidity range: 10% RH to 90% RH
・ Distance between chucks: 15 mm
・ Static load: Automatic ・ Strain amount: Automatic ・ Static / Power ratio: 1.5

Thermal conductivity under each condition at the initial stage of the vacuum heat insulating material using the outer packaging material for the vacuum heat insulating material, after holding at a temperature of 70 ° C. and a humidity of 90% RH for 400 hours, and after holding at a temperature of 70 ° C. and a humidity of 90% RH for 500 hours. Was measured. Each thermal conductivity was measured by the method described in the section "3.II.Vacuum heat insulating material" of "II. Vacuum heat insulating material". The results are shown in Table 3.
The vacuum heat insulating material was produced by the following method.

[Manufacturing of vacuum heat insulating material]
Two outer packaging materials (dimensions: 360 mm × 450 mm) obtained in Examples 1 to 5 and Comparative Examples 1 to 3 were prepared, and two heat-weldable films were stacked so as to face each other to form a quadrilateral. A bag body with only one side open was created by heat-sealing three sides. Glass wool having a size of 290 mm × 300 mm × 30 mm was used as the core material, and after the drying treatment, 10 g of calcium oxide was stored in the bag body as the core material and the desiccant, and the inside of the bag body was exhausted. Then, the opening portion of the bag body was sealed with a heat seal to obtain a vacuum heat insulating material. The ultimate pressure was 0.05 Pa.

As shown in Table 3, the B / A, which is the rate of change of the loss tangent tan δ during humidification, is 1 or more and 1.5 or less, and the C / B, which is the rate of change of the loss tangent tan δ during high humidity retention, is 0. In Examples 1 to 3 having a value of 8.8 or more and 1.2 or less, deterioration of the heat insulating performance of the vacuum heat insulating material could be suppressed even when the vacuum heat insulating material was used for a long time in a high temperature and high humidity environment.

Further, in Comparative Example 1 and Comparative Example 3, the gas barrier film and the heat-weldable film constituting the outer packaging material for the vacuum heat insulating material are the same, and there is a difference in the water vapor permeability of the manufactured outer packaging material for the vacuum heat insulating material. There wasn't. However, the rate of change during humidification of the loss tangent tan δ of Comparative Example 1 and Comparative Example 3 showed different behaviors, and a difference was also observed in the thermal conductivity after holding at a temperature of 70 ° C. and a humidity of 90% RH for 400 hours. From the above, it was suggested that considering the rate of change during humidification and the rate of change during high humidity retention of the loss tangent tan δ of the vacuum heat insulating material outer packaging material leads to suppression of the heat insulating performance of the vacuum heat insulating material.

1 ... Heat-weldable film 2A, 2B, 2C ... Gas barrier layer 3A, 3B, 3C ... Resin base material 4A, 4B, 4C ... Gas barrier film 10 ... Outer packaging material for vacuum heat insulating material 11 ... Core material 20 ... Vacuum heat insulating material

Claims (9)

One or more gas barrier layers having a heat-weldable film and a resin base material and gas barrier films arranged on one or both sides of the resin base material, which are located on the first main surface side of the heat-weldable film. It is an outer packaging material for vacuum heat insulating material having
The outer packaging material for vacuum heat insulating material is obtained by dynamic viscoelasticity measurement at a frequency of 10 Hz in a state where two identical outer packaging materials for vacuum heat insulating material are bonded to each other on the second main surfaces of the heat-weldable film. The loss tangent tan δ is measured, the value of the loss tangent tan δ in the initial state of temperature 70 ° C. and humidity 10% RH is A, and humidification immediately after humidification to temperature 70 ° C. humidity 90% RH at 5% RH / min from the initial state. When the value of the loss tangent tan δ in the time state is B and the value of the loss tangent tan δ at the time of high humidity holding at a temperature of 70 ° C. and humidity of 90% RH for 1 hour is C, the rate of change of the loss tangent tan δ during humidification. B / A is 1.0 or more and 1.5 or less, and C / B, which is the rate of change of the tangent tan δ at high humidity, is 0.8 or more and 1.2 or less. Outer packaging material. The packaging material for a vacuum heat insulating material according to claim 1, wherein the rate of change C / A of the loss tangent tan δ is 1.7 or less. The outer packaging material for a vacuum heat insulating material according to claim 1 or 2, wherein the heat-weldable film is a polyethylene film or a polypropylene film. The outer packaging material for a vacuum heat insulating material according to any one of claims 1 to 3, wherein the resin base material in at least one gas barrier layer is a polyester film. The outer packaging material for a vacuum heat insulating material according to any one of claims 1 to 4, wherein the gas barrier film is a metallic aluminum film. The outer packaging material for a vacuum heat insulating material according to any one of claims 1 to 5, wherein the outer packaging material for the vacuum heat insulating material has two or more gas barrier layers. The outer packaging material for a vacuum heat insulating material according to claim 6, wherein the outer packaging material for the vacuum heat insulating material has three gas barrier layers. A vacuum heat insulating material having a core material and an outer packaging material in which the core material is enclosed.
The vacuum heat insulating material, wherein the outer packaging material is the vacuum heat insulating outer packaging material according to any one of claims 1 to 7. An article having a heat insulating region and an article with a vacuum heat insulating material provided with the vacuum heat insulating material.
The vacuum heat insulating material has a core material and an outer packaging material in which the core material is enclosed.
An article with a vacuum heat insulating material, wherein the outer packaging material is the outer packaging material for vacuum heat insulating according to any one of claims 1 to 7.