JP2017133568A - Vacuum heat insulation material and equipment with vacuum heat insulation material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vacuum heat insulation material that can form a vacuum heat insulation material capable of maintaining adiabaticity for a long period.SOLUTION: A vacuum heat insulation material includes a core material and an outer packaging material for vacuum heat insulation material configured to enclose the core material. The core material contains inorganic fiber aggregate; inside the outer packaging material for the vacuum heat insulation material, absorbent is arranged; the outer packaging material for the vacuum heat insulation material includes a thermal welding layer, a barrier layer and a protection layer in this order; a product of tensile elasticity of the outer packaging material for the vacuum heat insulation material and cube of the thickness of the outer packaging material for the vacuum heat insulation material is equal to or less than 3.0 MPa mm; and each layer of the outer packaging material for the vacuum heat insulation material is arranged through polyester-based interlayer adhesive.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vacuum heat insulating material that can maintain heat insulating performance for a long period of time.

  In recent years, reduction of greenhouse gases has been promoted in order to prevent global warming, and energy saving is required for electrical products, vehicles, equipment and buildings. Among these, from the viewpoint of reducing power consumption, the use of vacuum heat insulating materials for electrical products is being promoted. In equipment that has a heat generating part inside the main body, such as electrical products, and equipment that has a heat retaining function using heat from the outside, it is possible to improve the heat insulation performance of the equipment as a whole by providing a vacuum heat insulating material It becomes. For this reason, efforts are being made to reduce the energy of devices such as electrical products by using vacuum heat insulating materials.

  The vacuum heat insulating material is a material in which a core material is disposed in a bag body formed of an outer packaging material, the inside of the bag body in which the core material material is disposed is depressurized to be in a vacuum state, and an end portion of the bag body is thermally welded. It is formed by sealing. Since the convection of the gas is blocked by making the inside of the heat insulating material a vacuum state, the vacuum heat insulating material can exhibit high heat insulating performance. Moreover, in order to maintain the heat insulation performance of a vacuum heat insulating material for a long period, it is necessary to maintain the inside of the bag body formed using the outer packaging material in a high vacuum state for a long time. For this reason, the outer packaging material is required to have various functions such as barrier performance for preventing gas from permeating from the outside and thermal adhesiveness for covering and sealing the core material. Therefore, the outer packaging material is configured as a laminate having a plurality of films having these functional characteristics. As an aspect of a general outer packaging material, a heat welding layer, a barrier layer, and a protective layer are laminated, and each layer is bonded via an interlayer adhesive or the like (see Patent Documents 1 and 2). ).

  Patent Document 1 describes that a two-layer nylon film is used as the outer packaging material for the purpose of preventing the vacuum state from being lowered due to the generation of pinholes in the barrier layer due to piercing or the like.

  Moreover, in patent document 2, when forming a vacuum heat insulating material using the said outer packaging material, it aims at the edge part which bonded together the said outer packaging materials, and shall not have the influence of a bending directly on a barrier layer. In other words, it is described that protective layers having a high tensile elastic modulus are disposed on both sides of the barrier layer.

JP 2003-262296 A JP 2013-103343 A

  However, the outer packaging materials of Patent Literature 1 and Patent Literature 2 are formed of a vacuum heat insulating material using the outer packaging material even when the outer packaging material alone has been confirmed to exhibit sufficient barrier performance. In this case, there is a problem that the vacuum state cannot be maintained sufficiently and the heat insulating performance cannot be maintained for a long time. In particular, when using a vacuum heat insulating material formed using the outer packaging material, a bent portion formed by bending an end portion where the outer packaging materials are bonded together, and the vacuum heat insulating material has a curved surface. There is a problem that a crack is generated in the barrier layer at a bent portion formed when bent along the surface, and the vacuum state is lowered.

  Moreover, even when a vacuum heat insulating material having a low initial thermal conductivity is obtained by forming a vacuum heat insulating material using an outer packaging material having a high barrier performance, a volatile gas is contained in the member constituting the vacuum heat insulating material. In this case, since the volatile gas is diffused inside the vacuum heat insulating material as time passes, the degree of vacuum inside the vacuum heat insulating material decreases. In particular, for members such as a heat-welded layer, an interlayer adhesive, and a core material arranged inside the barrier layer, the volatilized gas stays inside the vacuum heat insulating material. The impact on general change will be greater. Therefore, in order to obtain a vacuum heat insulating material capable of maintaining higher heat insulating performance over a longer period, it is required to further suppress the amount of volatile gas from each member constituting the vacuum heat insulating material.

  This invention is made | formed in view of the said problem, and it aims at providing the vacuum heat insulating material etc. which can maintain heat insulation performance for a long period of time.

The present invention is a vacuum heat insulating material having a core material and an outer packaging material for a vacuum heat insulating material that encloses the core material, the core material containing an inorganic fiber assembly, and the outer packaging material for a vacuum heat insulating material An adsorbent is disposed inside, and the outer packaging material for vacuum heat insulating material has a heat-welded layer, a barrier layer, and a protective layer in this order, and the tensile elastic modulus of the outer packaging material for vacuum heat insulating material and the above The product of the vacuum insulation outer packaging material and the cube of the thickness (hereinafter sometimes referred to as function M) is 3.0 MPa · mm ³ or less, and each layer of the vacuum insulation outer packaging material is made of polyester. Disclosed is a vacuum heat insulating material, characterized in that the vacuum heat insulating material is disposed through an interlayer adhesive of the system.

In the present invention, the outer packaging material for vacuum heat insulating material has a high barrier performance, the amount of volatile gas derived from each member constituting the vacuum heat insulating material is suppressed, and the above outer packaging material for vacuum heat insulating material When the value of the function M is equal to or less than a predetermined value, when using the vacuum heat insulating material formed using the vacuum heat insulating material outer packaging material of the present invention, the vacuum heat insulating material outer packaging materials are bonded together. It is possible to suppress the occurrence of cracks in the barrier layer at the bent portion formed by bending the end portion. In addition, since the water vapor that enters the vacuum heat insulating material from the heat-welded portion of the outer packaging material for the vacuum heat insulating material is also adsorbed by the adsorbent, the degree of vacuum inside the vacuum heat insulating material can be maintained high over a long period of time, It can be set as the vacuum heat insulating material which can maintain heat insulation performance for a long period of time.

  In the above invention, the heat welding layer is a layer mainly composed of polybutylene terephthalate, the barrier layer is an aluminum foil layer, and the protective layer is a layer mainly composed of polyethylene terephthalate. Is preferred. When forming a vacuum heat insulating material using an outer packaging material having a layer structure of the above combination, generation of cracks in the barrier layer in a bent portion formed by bending an end portion where the outer packaging materials are bonded together is performed. It is because it can be set as the vacuum heat insulating material which can be suppressed and can maintain heat insulation performance for a long period of time.

  In the present invention, the increase in the thermal conductivity of the vacuum heat insulating material after being allowed to stand in an environment of 130 ° C. for 1000 hours with respect to the initial heat conductivity of the vacuum heat insulating material is 2 mW / m · K or less. Preferably there is. It is because it can be set as the vacuum heat insulating material which can maintain heat insulation performance for a long term because the time-dependent change of the heat conductivity of a vacuum heat insulating material is in the said range.

The present invention is an apparatus having a heat source part or a heat retaining part in the main body or inside, and an apparatus with a vacuum heat insulating material provided with at least a vacuum heat insulating material, wherein the vacuum heat insulating material is a core and a vacuum in which the core material is sealed And the core material contains an inorganic fiber assembly, and an adsorbent is disposed inside the vacuum insulation material outer packaging material, and the vacuum insulation material packaging material is , Having a heat-welded layer, a barrier layer, and a protective layer in this order, and the product of the tensile elastic modulus of the vacuum insulation material outer packaging material and the cube of the thickness of the vacuum insulation material outer packaging material is 3.0 MPa · and in mm ³ or less, each of the vacuum heat insulating material for outer material provides a vacuum insulation material-attached device, characterized in that it is arranged through the interlayer adhesive polyester.

  According to the present invention, since the vacuum heat insulating material is the above-described vacuum heat insulating material of the present invention and can maintain heat insulating performance for a long period of time, in a device having a heat source portion, Insulating the heat from the heat, it is possible to prevent the temperature of the entire device from becoming high. On the other hand, in a device having a heat retaining part, the temperature state of the heat retaining part can be maintained by the vacuum heat insulating material. Thereby, it can be set as the apparatus which has the high energy saving characteristic which suppressed power consumption.

  In this invention, there exists an effect that the vacuum heat insulating material etc. which can maintain heat insulation performance for a long period of time can be provided.

It is a schematic sectional drawing which shows an example of the vacuum heat insulating material of this invention. It is explanatory drawing which shows an example of the use condition of the vacuum heat insulating material of this invention. It is explanatory drawing explaining the bending state in a bending part. It is a graph which shows the time-dependent change of the heat conductivity of the vacuum heat insulating material measured by the Example and the comparative example. It is a graph which shows the time-dependent change of the heat conductivity of the vacuum heat insulating material measured in the Example. It is a graph which shows the oxygen barrier performance with respect to the value of the function M measured in the reference example.

The present invention relates to a vacuum heat insulating material and a device with a vacuum heat insulating material. Hereinafter, the vacuum heat insulating material and the apparatus with the vacuum heat insulating material of the present invention will be described.
In this specification, “external packaging material for vacuum heat insulating material” may be abbreviated as “external packaging material”, “polybutylene terephthalate” as “PBT”, and “polyethylene terephthalate” as “PET”.

A. Vacuum heat insulating material First, the vacuum heat insulating material of this invention is demonstrated.
The vacuum heat insulating material of the present invention is a vacuum heat insulating material having a core material and an outer packaging material for a vacuum heat insulating material that encloses the core material, the core material containing an inorganic fiber aggregate, and the vacuum heat insulating material. An adsorbent is disposed inside the outer packaging material for the material, and the outer packaging material for the vacuum heat insulating material has a thermal welding layer, a barrier layer, and a protective layer in this order. The product of the modulus of elasticity and the cube of the thickness of the outer packaging material for vacuum heat insulating material is 3.0 MPa · mm ³ or less, and each layer of the outer packaging material for vacuum heat insulating material is interposed via a polyester-based interlayer adhesive It is characterized by being arranged.

  The vacuum heat insulating material of the present invention will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing an example of the vacuum heat insulating material of the present invention. As illustrated in FIG. 1, the vacuum heat insulating material 10 of the present invention includes a core material 1 and a vacuum heat insulating material packaging material 20 that encloses the core material 1. The outer packaging material 20 for vacuum heat insulating material has a heat welding layer 2, a barrier layer 3, and a protective layer 4 in this order, and each layer of the outer packaging material 20 for vacuum heat insulating material is arranged via an interlayer adhesive 5. ing. Further, an adsorbent 6 is disposed inside the outer packaging material 20 for vacuum heat insulating material. The vacuum heat insulating material 10 has two outer packaging materials 20 for the vacuum heat insulating material facing each other so that the respective heat-welding layers 2 face each other, and the core material 1 is disposed between them. One end of the outer periphery is used as an opening, and the end portions 12 of the remaining three outer packaging materials for vacuum heat insulating material 20 are thermally welded to form the two outer packaging materials for vacuum heat insulating material 20, and the core inside A core body 1 is prepared, and then the opening 1 is sealed in a state in which the internal pressure of the bag body is reduced, whereby the core material 1 is enclosed in the vacuum insulation outer packaging material 20. It is what.

  In the present invention, the outer packaging material for vacuum heat insulating material has a high barrier performance, the amount of volatile gas derived from each member constituting the vacuum heat insulating material is suppressed, and the above outer packaging material for vacuum heat insulating material When the value of the function M is equal to or less than a predetermined value, when using the vacuum heat insulating material formed using the vacuum heat insulating material outer packaging material of the present invention, the vacuum heat insulating material outer packaging materials are bonded together. It is possible to suppress the occurrence of cracks in the barrier layer at the bent portion formed by bending the end portion. In addition, since the water vapor that enters the vacuum heat insulating material from the heat-welded portion of the outer packaging material for the vacuum heat insulating material is also adsorbed by the adsorbent, the degree of vacuum inside the vacuum heat insulating material can be maintained high over a long period of time, It can be set as the vacuum heat insulating material which can maintain heat insulation performance for a long period of time.

  The vacuum heat insulating material of the present invention includes at least a core material, an adsorbent, and a vacuum heat insulating material outer packaging material having a heat welding layer, a barrier layer, a protective layer, and an interlayer adhesive. Each configuration will be described below.

I. Core material The core material in this invention is enclosed with the envelope material for vacuum heat insulating materials mentioned later. In the present invention, a core material containing an inorganic fiber aggregate is used.

  The core material is not particularly limited as long as it contains an inorganic fiber aggregate. In the present invention, the core material preferably does not contain a binder. When inorganic fibers are aggregated using a binder, an inorganic fiber aggregate excellent in shape stability can be obtained. However, the use of the above binder increases the solid component in the core material, so it is difficult to improve the heat insulation performance of such a core material. In addition, since an organic material is usually used as a binder, using a binder for the core material increases the amount of volatile gas contained in the core material. In the present invention, since the core material does not contain a binder, the heat insulating performance of the vacuum heat insulating material can be improved, and the vacuum degree inside the vacuum heat insulating material can be maintained high over a long period of time. is there.

  In the present invention, “does not contain a binder” means that the content of the binder contained in the core material is 1% by mass or less, particularly 0.1% by mass or less of the whole core material. preferable. Here, the “binder” means an organic material or an inorganic material used for binding inorganic fibers used in the core material. In the present invention, in particular, the core material is preferably a core material composed only of inorganic fiber aggregates.

  The inorganic fiber constituting the inorganic fiber aggregate is not particularly limited as long as it is a fibrous inorganic material. For example, glass fiber such as glass wool or glass fiber, alumina fiber, silica alumina fiber, silica fiber, ceramic A fiber, rock wool, etc. can be mentioned, Among these, glass wool is used suitably. These inorganic fibers are preferable in that they have low thermal conductivity and are easier to handle than powders. The core material may be the above-mentioned material alone or a composite material in which two or more materials are mixed.

  The method of using the inorganic fiber as an aggregate is not particularly limited, and the inorganic fiber aggregate can be obtained by a known method. For example, an inorganic fiber aggregate can be obtained by compressing inorganic fibers using a press machine or the like under atmospheric pressure or reduced pressure. You may perform the said compression process, heating an inorganic fiber. Moreover, it is good also as an inorganic fiber aggregate | assembly by binding the said inorganic fiber with the bag body and belt | band | zone different from an outer packaging material. As such a bag body or belt body, for example, a known resin film such as polypropylene resin or polyethylene resin can be used. An inorganic fiber aggregate in a state of being bound by the bag or band may be used as a core material, and after the inorganic fiber is aggregated, the bag or band is removed and only the inorganic fiber aggregate is removed. It may be used as a core material.

  The core material preferably has a low thermal conductivity, and is preferably a porous material having a porosity of 50% or more, particularly 90% or more. The diameter of the inorganic fiber is preferably in the range of 1 μm to 20 μm, and more preferably in the range of 2 μm to 10 μm, from the viewpoints of rigidity, productivity, and thermal conductivity as the core material.

II. Adsorbent In the present invention, an adsorbent such as a moisture adsorbent for adsorbing moisture in the vacuum heat insulating material and a gas adsorbent for adsorbing gas is disposed inside the outer packaging material. By providing such an adsorbent inside the vacuum heat insulating material, it adsorbs gas and moisture entering from the heat-welded part of the outer packaging material, especially the outer packaging material, and increases the degree of vacuum inside the vacuum heat insulating material over a long period of time. Can be maintained.

  The adsorption mechanism of the adsorbent such as the moisture adsorbent or the gas adsorbent may be any of physical adsorption, chemical adsorption, occlusion and sorption, but a substance that acts as a non-evaporable getter is good. Specific examples include physical adsorbents such as synthetic zeolite, activated carbon, activated alumina, silica gel, dosonite, and hydrotalcite. Further, solidified inorganic fine particles such as silica and pearlite are sometimes used as a core material of a vacuum heat insulating material. However, since these fine particles have adsorptivity, they can also be used as an adsorbent.

  As the chemical adsorbent, alkali metal or alkaline earth metal oxides, alkali metal or alkaline earth metal hydroxides, etc. can be used, and in particular, lithium oxide, lithium hydroxide, calcium oxide, calcium hydroxide, Magnesium oxide, magnesium hydroxide, barium oxide, and barium hydroxide are effective. In addition, calcium sulfate, magnesium sulfate, sodium sulfate, sodium carbonate, potassium carbonate, calcium chloride, lithium carbonate, unsaturated fatty acid, iron compound and the like also act effectively. In addition, a getter material obtained by singly or alloying materials such as barium, magnesium, calcium, strontium, titanium, zirconium, and vanadium can also be used. Furthermore, in order to adsorb and remove at least nitrogen, oxygen, moisture, and carbon dioxide, the getter material can be applied in various mixtures.

  In the present invention, the adsorbent is preferably a moisture adsorbent. After forming the vacuum heat insulating material using the outer packaging material having high barrier performance, the value of the function M of the outer packaging material for the vacuum heat insulating material is set to a predetermined value or less, thereby the outer packaging material for the vacuum heat insulating material. Even if it suppresses the occurrence of cracks in the above-mentioned barrier layer in a bent portion formed by bending the end portion bonded together, it is difficult to impart barrier performance to the heat-welded portion between the outer packaging materials It is difficult to completely block the water vapor from entering the inside of the vacuum heat insulating material through the heat welding portion. Therefore, it is effective to arrange the moisture adsorbent inside the vacuum heat insulating material to prevent water vapor from gradually entering from the heat-welded portion and reducing the degree of vacuum inside the vacuum heat insulating material over time. is there. As such a moisture adsorbent, calcium oxide or the like can be used.

III. Outer packaging material for vacuum insulation 1. Interlayer adhesive Each layer constituting the outer packaging material in the present invention is disposed via an interlayer adhesive. This is because by laminating each layer via an interlayer adhesive, each layer constituting the outer packaging material can be bonded more firmly, and a vacuum heat insulating material that can maintain heat insulating performance for a long time can be obtained. .

  Since the amount of the interlayer adhesive used is smaller than that of other components of the vacuum heat insulating material, no attention has been paid to the volatile gas contained in the interlayer adhesive so far. However, using a core material that does not contain a binder, changing the type of interlayer adhesive to produce a vacuum heat insulating material, and measuring the temporal change in thermal conductivity, the thermal conductivity depends on the type of interlayer adhesive used It was found that there was a difference in the amount of change over time. In particular, since the interlayer adhesive used for bonding the heat-welded layer and the barrier layer is located inside the barrier layer, even if the amount of the interlayer adhesive used is small, the vacuum insulation material vacuum The influence on the change over time is great and cannot be ignored.

  Although there are various types of adhesives that are generally used, the present inventor has conducted research to solve the above problems, and as a result, among the various adhesives, the amount of volatile gas of polyester-based adhesives. As a result, the inventors have found that there are few, and have completed the present invention.

  That is, in the present invention, a polyester-based adhesive is used as the interlayer adhesive. Urethane adhesives and epoxy adhesives frequently used as general adhesives include a cyclic structure having water absorption, but polyester adhesives do not include such a cyclic structure and have low water absorption. This is because the amount of water vapor volatilized from the interlayer adhesive can be suppressed.

  The polyester adhesive in the present invention includes a polyester resin and a curing agent capable of causing a crosslinking reaction with the polyester resin. Each will be described below.

(1) Polyester resin The polyester resin can be obtained by polycondensation of a dicarboxylic acid component and a diol component. The dicarboxylic acid component is not particularly limited. For example, aromatic dicarboxylic acids such as isophthalic acid, terephthalic acid, diphenyl dicarboxylic acid, diphenyl ether dicarboxylic acid, diphenyl sulfone dicarboxylic acid, naphthalenedicarboxylic acid, adipic acid, Examples thereof include aliphatic dicarboxylic acids such as sebacic acid. These dicarboxylic acids may be used alone or in any combination of two or more.

  The diol component is not particularly limited. For example, alkylene glycol such as trimethylene glycol, tetramethylene glycol and hexamethylene glycol, aromatic diol such as hydroquinone, resorcin, and bisphenol A, bis (hydroxyethoxyphenyl) ) Sulfone, aliphatic diols such as bis (hydroxyethoxyphenyl) propane, and diethylene glycol. These diols may be used alone or in any combination of two or more.

(2) Curing agent Examples of the curing agent include compounds having two or more reactive groups in one molecule. Typical curing agents include toluene diisocyanates or isophorone diisocyanates of polyalcohols such as trimethylolpropane, adducts with diisocyanate compounds, nopolac polyisocyanates, etc. If necessary, some or all of the isocyanate groups are caprolactam. Further, those stabilized with a known blocking agent such as phenol or oxime can be used.

  Further, as a curing agent, an epoxy compound such as a bisphenol A type epoxy compound, a novolak type epoxy compound or triglycidyl isocyanurate, a metal complex compound such as hexamethoxymethylmelamine, melamine-formaldehyde resin, iron-acetylacetone, etc. may be used. it can.

  The polyester-based adhesive in the present invention comprises the polyester-based resin in the range of 70 to 99 parts by weight, particularly 85 to 98 parts by weight, and the curing agent in the range of 30 to 1 part by weight. It is preferable that it is contained within the range, especially within the range of 15 parts by weight to 2 parts by weight. When the polyester resin exceeds 99 parts by weight and the curing agent is less than 1 part by weight, the heat resistance and water resistance are lowered. Conversely, the polyester resin is less than 70 parts by weight, and the curing agent is This is because if it exceeds 30 parts by weight, the initial adhesiveness is greatly lowered.

(3) Other components Although the polyester-type adhesive in this invention contains the said polyester-type resin and the said hardening | curing agent, a well-known resin, a pigment, etc. can be used together as needed. Examples of known resins include polyester resins such as acrylic resins, alkyd resins, and urethane resins, and examples of pigments include titanium oxide, silica, talc, and zinc chromate.

(4) Interlaminar Adhesive The melting point of the interlaminar adhesive is preferably higher than the use environment temperature of the vacuum heat insulating material of the present invention, preferably in the range of 200 ° C to 600 ° C, and more preferably in the range of 250 ° C to It is preferable to be within the range of 500 ° C. In addition, the glass transition temperature (Tg) of the interlayer adhesive is preferably in the range of −60 ° C. to 30 ° C., and more preferably in the range of −50 ° C. to 20 ° C. By setting the melting point and glass transition temperature of the interlayer adhesive within the above ranges, the interlayer adhesive has flexibility and elasticity, so that it can follow a desired shape when forming the vacuum heat insulating material. Moreover, since the wettability with each layer which comprises the outer packaging material for vacuum heat insulating materials becomes favorable under use temperature, it can have a high adhesive force in the bonding surface of the outer packaging materials for vacuum heat insulating materials. For this reason, even if it exposes for a long time under high temperature, generation | occurrence | production of peeling etc. can be prevented in the said bonding surface. Furthermore, deterioration of the outer packaging material for vacuum heat insulating material can be suppressed even in an environment where a heat cycle (thermal shock) occurs. In addition, melting | fusing point and glass transition temperature of the said interlayer adhesive are the values measured by differential operation calorimetry (DSC).

  The decomposition temperature of the interlayer adhesive is preferably in the range of 250 ° C to 600 ° C, and more preferably in the range of 300 ° C to 550 ° C. By setting the decomposition temperature of the interlayer adhesive in the above range, the interlayer adhesive is thermally deteriorated under the normal use environment of the vacuum heat insulating material, and the adhesive force of the bonding surface between the outer packaging materials for the vacuum heat insulating material is reduced. This is because it can be prevented. The decomposition temperature of the interlayer adhesive is a value measured by differential thermal-thermogravimetric simultaneous measurement (TG-DTA).

  The adhesive strength of the interlayer adhesive is preferably 0.5N or more, more preferably 3N or more, and particularly preferably 5N or more. When the adhesive strength of the interlayer adhesive is within the above range, it is possible to suppress the occurrence of peeling between the thermal welding layer and the other layers. In addition, the said adhesive force is the value measured based on JIS-Z-1707.

The interlayer adhesive may be a layered film or the like in advance, and a coating solution prepared by mixing the above-mentioned interlayer adhesive material in a desired solvent is prepared, and the thermal welding layer is laminated on another layer. When performing, you may apply | coat directly on the surface of either layer. Examples of the method for applying the interlayer adhesive include a roll coating method, a gravure roll coating method, a kiss coating method, and other coating methods. The coating amount of the interlayer adhesive, can be set appropriately, usually, it is desirable that the 0.1g ^{/ m 2} ~10g ^/ m 2 approximately in the dry state.

2. Heat-welding layer The heat-welding layer in the present invention is a layer constituting a part of the outer packaging material, and when the vacuum heat insulating material is formed using the outer packaging material, it becomes a part in contact with the core material, and the outer packaging materials facing each other It arrange | positions in the site | part which forms the heat welding surface which heat-welds the edge part of this.

  As a material for such a heat-welded layer, a thermoplastic resin is preferable because it can be melted and fused by heating. For example, polyethylene such as linear short-chain branched polyethylene or unstretched polypropylene (CPP) , Polyolefin resins such as cycloolefin copolymer (COC), polyester resins such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), polyvinyl acetate resins, polyvinyl chloride resins, Examples include poly (meth) acrylic resins and urethane resins. In the present invention, among these, the material is preferably linear short-chain branched polyethylene, unstretched polypropylene or polybutylene terephthalate, and in particular, it may be mainly composed of polybutylene terephthalate (PBT). preferable. When the heat insulation layer is mainly composed of PBT, when the vacuum heat insulating material is formed, the generation of cracks in the barrier layer is further suppressed at the end portion where the outer packaging materials are bonded together. Because you can.

  The main component of PBT in the heat-welded layer is a polymer having a polybutylene terephthalate skeleton (hereinafter referred to as a PBT skeleton) obtained by polycondensation of 1,4-butanediol and terephthalic acid. Say that. Specifically, it means that the polymer having the PBT skeleton is contained most, for example, 50% by weight or more in the total composition of the heat-welded layer.

  The heat-welded layer in the present invention may be any material that has as a main component a polymer having a PBT skeleton in the above-mentioned proportion in the heat-welded layer. Such a heat-welded layer is composed of, for example, a polybutylene terephthalate homopolymer obtained by polycondensation of 1,4-butanediol and terephthalic acid (hereinafter sometimes referred to as PBT homopolymer). A polybutylene terephthalate copolymer modified by substituting one or both of 1,4-butanediol and terephthalic acid with a copolymer component such as another diol component or dicarboxylic acid component (hereinafter referred to as “polybutylene terephthalate copolymer”) Or may be referred to as a PBT copolymer). Moreover, the said heat welding layer may contain both a PBT homopolymer and a PBT copolymer as a polymer which has PBT frame | skeleton. Furthermore, the heat-welded layer may contain a thermoplastic material in addition to the above-described PBT homopolymer and PBT copolymer.

(1) Polymer having PBT skeleton The polymer having a PBT skeleton is either a PBT homopolymer or a PBT copolymer.

(I) PBT homopolymer The PBT homopolymer is obtained by polycondensation of 1,4-butanediol and terephthalic acid. In addition, what was polycondensed using dimethyl terephthalate instead of terephthalic acid may be used.

(Ii) PBT copolymer The PBT copolymer is obtained by substituting one or both of 1,4-butanediol and terephthalic acid constituting the PBT homopolymer with another diol component or dicarboxylic acid component. It has been denatured. The PBT copolymer may be a random copolymer or a block copolymer.
In the following description, the diol component excluding 1,4-butanediol and the dicarboxylic acid component excluding terephthalic acid or dimethyl terephthalate in the PBT copolymer may be collectively referred to as a copolymerizable monomer.

  Examples of the diol component used in the PBT copolymer include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,5-pentanediol, and 1,6-hexanediol. , Aliphatic diols such as neopentyl glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, alicyclic diols such as 1,4-cyclohexanedimethanol and 1,4-cyclohexanediethanol, ethylene oxide of bisphenol A and bisphenol S, Or, mention may be made of aromatic diols such as propylene oxide adducts, polyfunctional alcohols such as trimethylolpropane, glycerin and pentaerythritol, or ester-forming derivatives thereof. Can. The above-mentioned diol component may be contained alone as a copolymerizable monomer in the PBT copolymer, or two or more kinds may be contained.

  Examples of the dicarboxylic acid component used in the PBT copolymer include succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedicarboxylic acid, dodecanedicarboxylic acid, hexadecanedicarboxylic acid, Aliphatic dicarboxylic acids such as dimer acid, hexahydrophthalic acid, hexahydroisophthalic acid, hexahydroterephthalic acid, alicyclic dicarboxylic acid such as hymic acid, phthalic acid, isophthalic acid; naphthalene such as 2,6-naphthalenedicarboxylic acid 4,4'-diphenyldicarboxylic acid, 4,4'-diphenoxyether dicarboxylic acid, 4,4'-diphenylether dicarboxylic acid, 4,4'-diphenylmethanedicarboxylic acid, 4,4'-diphenylketone dicarboxylic acid Aromatic dicarboxylic acids such as Or these ester formation derivatives etc. can be mentioned. Furthermore, you may use polyvalent carboxylic acid etc. together as needed. The above-mentioned dicarboxylic acid component may be contained alone as a copolymerizable monomer in the PBT copolymer, or two or more kinds thereof may be contained.

  As a modification amount of 1,4-butanediol and terephthalic acid in the PBT copolymer, when the above PBT copolymer is used alone, or when the above PBT homopolymer and the above PBT copolymer are used in combination. Accordingly, it can be set as appropriate.

(2) Thermoplastic material The heat-welded layer in the present invention may contain a thermoplastic material in addition to containing at least one of the above-described PBT homopolymer and PBT copolymer. Examples of the thermoplastic material include a thermoplastic resin not having a PBT skeleton, a thermoplastic elastomer, and the like.
Examples of the thermoplastic resin having no PBT skeleton include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyphenylene sulfide (PPS), polyamide (PA), polyimide (PI), polyamideimide (PAI), Examples include polyether sulfone (PES), polyether ether ketone (PEEK), polycarbonate (PC), polyurethane, fluororesin, polyolefins such as polyethylene and polypropylene, and polyvinyl chloride. The above thermoplastic resins may be used alone or in combination of two or more.
Examples of the thermoplastic elastomer include styrene elastomers, olefin elastomers, polyvinyl chloride elastomers, urethane elastomers, polyester elastomers, polyamide elastomers, and the like. The above-mentioned thermoplastic elastomers may be used alone or in combination of two or more.
In addition, when a heat welding layer contains the above-mentioned thermoplastic material, as content of the thermoplastic material with respect to the whole quantity (100 weight%) of the said heat welding layer, it contains less than content of the polymer which has PBT frame | skeleton. Any amount can be used and can be set as appropriate.

(3) Other materials In addition to the above-mentioned materials, the heat welding layer in the present invention is a stabilizer such as a plasticizer, an antioxidant and an ultraviolet absorber, an antistatic agent, a surfactant, and an improvement in fluidity. It may contain other materials such as a lubricant, a crystallization accelerator (nucleating agent), an anti-blocking agent, a flame retardant, an organic filler, and an inorganic filler.

(4) Heat-welded layer The number-average molecular weight of the heat-welded layer is preferably within a range where desired heat-weldability can be exhibited, and can be appropriately selected according to the adhesive strength of the heat-welded layer.

  The melting point of the heat-welded layer is preferably higher than the maximum temperature reached at the site where the vacuum heat insulating material is used, and is preferably in the range of 100 ° C. or higher and 250 ° C. or lower, and particularly 110 ° C. or higher and 240 ° C. It is preferably within the following range, and particularly preferably within the range of 120 ° C. or higher and 230 ° C. or lower.

  In addition, the glass transition temperature (Tg) of the heat-welded layer may be any temperature that allows the vacuum insulation outer packaging material to exhibit high adhesion and high durability under the usage environment. It can be appropriately set according to the assumed maximum temperature, the type of each material included in the heat-welded layer, the content ratio thereof, and the like.

The glass transition temperature (Tg) of the heat-welded layer in the case where the outer packaging material for a vacuum heat insulating material of the present invention is used in a temperature environment of 100 ° C. or higher is not particularly limited as long as it is a temperature that can exhibit heat-weldability. However, in particular, when the outer packaging material for a vacuum heat insulating material of the present invention is used in a temperature environment of 150 ° C. or higher, the glass transition temperature (Tg) of the heat-welded layer is preferably 60 ° C. or higher.
When the melting point and the glass transition temperature of the heat-welded layer are within the above ranges, a desired shape can be followed when the core material is sealed using the outer packaging material for a vacuum heat insulating material of the present invention. In addition, since the wettability of the bonding surfaces of the outer packaging materials for vacuum heat insulating materials becomes high at the use temperature, it can exhibit high adhesive force and peel off on the bonding surfaces even if exposed for a long time at high temperature. Etc. can be prevented.

  The tensile modulus of the heat-welded layer is not particularly limited as long as the value of the function M can be set to a predetermined value or less, but is preferably 1.0 GPa or more. However, it is preferably within the range of 1.0 GPa to 5.0 GPa, and particularly preferably within the range of 1.5 GPa to 4.0 GPa. Due to the tensile elastic modulus of the heat-welded layer being within the above range, when the vacuum heat insulating material is formed, the occurrence of cracks in the barrier layer is further suppressed at the end where the outer packaging materials are bonded together. Because it can be done. Moreover, it is because generation | occurrence | production of the pinhole by the stab from the core material used for the said vacuum heat insulating material can be suppressed.

  Further, as will be described later, from the viewpoint that the tensile elastic modulus of the two layers sandwiching the barrier layer adjacent to each other is preferably within a predetermined range, the tensile elastic modulus of the thermally welded layer is within the above range. By being inside, it becomes possible to use the said heat welding layer as one of the two layers which pinch | interpose the said barrier layer adjacently. Therefore, it is unnecessary to dispose an inner surface side protective layer or the like having a predetermined tensile modulus between the barrier layer and the heat-welded layer as one of the two layers sandwiching the barrier layer adjacent to each other. This is because the outer packaging material can have a small layer structure. As a result, the value of the function M can be easily set to a predetermined value or less.

  The thickness of the heat-welding layer may be any thickness that can increase the adhesive force when the outer packaging material for vacuum heat insulating material is bonded by heat welding, and is preferably in the range of 20 μm to 100 μm, and in particular, 25 μm to 90 μm. Is preferably within the range of 30 μm to 80 μm. When the thickness of the heat-welded layer is larger than the above range, the barrier property, the appearance, and the like as the entire outer packaging material for a vacuum heat insulating material may be deteriorated. On the other hand, if the thickness of the heat-welded layer is smaller than the above range, desired adhesive strength cannot be obtained, and peeling or the like may occur during long-term use at high temperatures.

  The sealing strength between the heat-welded layers may be any strength as long as the vacuum insulation outer packaging material can exhibit high adhesion and high durability under the usage environment, and is the maximum temperature expected under the usage environment. And it can set suitably according to the kind of each material contained in a heat welding layer, and its content rate. Especially, when the vacuum heat insulating material of the present invention is used in a temperature environment of 150 ° C. or higher, it is preferable that the sealing strength of the heat-welded layer is 15 N or higher. The seal strength is a value measured based on the standard of JIS-Z-1707.

  As the heat-welding layer, a commercially available heat-welding layer having the above-described composition may be used. For example, the heat-welding layer may be formed by the following method. As a method for forming the heat-welded layer, any method can be used as long as it can be formed on another layer such as a barrier layer via an interlayer adhesive. Specific methods include wet lamination method, dry lamination method, solventless dry lamination method, extrusion lamination method, T-die coextrusion molding method, coextrusion lamination method, inflation method. Using other methods, a film can be formed on another layer whose surface is coated with an interlayer adhesive.

3. Barrier layer The barrier layer in this invention is a site | part formed between the said heat welding layer in an outer packaging material, and the protective layer mentioned later normally.

  Examples of the barrier layer include a metal film such as aluminum, nickel, stainless steel, iron, copper, and titanium, a vapor deposition film obtained by vapor-depositing an inorganic substance such as metal, metal oxide, and silicon oxide on one side of the resin film. Those generally used as a barrier layer, such as those provided with a barrier coating film made of a barrier composition containing at least one of an alcohol-based resin and an ethylene vinyl alcohol copolymer, can also be used. In the present invention, the barrier layer is preferably a metal foil layer, and more preferably an aluminum foil layer. It is because it can be set as the vacuum heat insulating material which does not deteriorate for a long time and can maintain heat insulation performance.

  The barrier layer may be a single layer, or a multilayer body in which layers made of the same material or layers made of different materials are laminated. In addition, the barrier layer may be subjected to a surface treatment such as a corona discharge treatment from the viewpoint that the barrier performance and the adhesion with other layers can be improved.

  The thickness of the barrier layer is, for example, preferably in the range of 2 μm to 50 μm, more preferably in the range of 5 μm to 12 μm. If the thickness of the barrier layer is smaller than the above range, pinholes and the like are likely to occur at the bent portion, and the barrier performance may be deteriorated. On the other hand, if the thickness of the barrier layer is larger than the above range, vacuum insulation is performed. This is because heat bridge is likely to occur in the material, and the heat insulation performance may be lowered.

As the barrier performance of the barrier layer, the oxygen permeability is preferably 0.1 cc / m ² / day / atm or less, and more preferably 0.05 cc / m ² / day / atm or less. It is preferable that water vapor permeability is less than 0.1g ^/ m 2 ^/ day, preferably at most among them 0.05g ^/ m 2 ^/ day. When the oxygen and water vapor permeability of the barrier layer is within the above-described range, it is possible to make it difficult for water, gas, or the like that has permeated from the outside to penetrate into the inner core material. In addition, the said oxygen permeability can be made into the value measured using the oxygen permeability measuring apparatus on condition of temperature 23 degreeC and humidity 60% RH based on JIS-K-7126B. Examples of the oxygen permeability measuring device include OXTRAN manufactured by MOCON (USA). The water vapor permeability can be measured according to JIS K7129 using a water vapor permeability measuring device under conditions of a temperature of 40 ° C. and a humidity of 90% RH. As the water vapor transmission rate measuring apparatus, Permatran manufactured by MOCON (USA) can be used.

4). Protective layer The protective layer is a portion that becomes the outermost layer (outermost layer) in the outer packaging material. The protective layer has sufficient strength to protect the inside of the vacuum heat insulating material when the outer heat insulating material is used to form the vacuum heat insulating material, and has heat resistance, moisture resistance, pin hole resistance, and puncture resistance. It is preferable that it is excellent in property etc.

  The protective layer only needs to use a resin having a higher melting point than the heat-welded layer, and may be in the form of a sheet or film. Examples of such a protective layer include sheets or films of nylon resin, polyester resin, polyamide resin, polypropylene resin, and the like. In the present invention, the material constituting the protective layer is preferably a polyester resin. From the viewpoints of toughness, oil resistance, chemical resistance, availability, etc., the protective layer is particularly preferably a layer mainly composed of polyethylene terephthalate (PET).

  The phrase “mainly comprising PET in the protective layer” means that the main component is a polymer having a PET skeleton obtained by dehydration condensation of terephthalic acid and ethylene glycol. Specifically, it means that the polymer having the PET skeleton is most contained in the total composition of the protective layer, for example, 50% by weight or more. As such a layer having PET as a main component, a commercially available PET film or a PET film produced by a known method can be used.

  The protective layer may be a single layer or may be a multilayer formed by laminating layers made of the same material or layers made of different materials. The protective layer may be subjected to a surface treatment such as a corona discharge treatment from the viewpoint of improving the adhesion with other layers.

  The thickness of the protective layer is not particularly limited as long as it can protect the heat-welded layer and the barrier layer, but is generally in the range of 5 μm to 80 μm.

5. Outer packaging material for vacuum insulation (1) Function M
In the outer packaging material, the product (function M) of the tensile elastic modulus of the outer packaging material and the cube of the thickness of the outer packaging material is a predetermined value or less.

  FIG. 2 is an explanatory view showing an example of a usage state of the vacuum heat insulating material, and is a cross-sectional view showing an example in which two vacuum heat insulating materials are used side by side. In FIG. 2, the two vacuum heat insulating materials 10 are arranged in a state in which a bent portion 13 is formed by bending an end portion 12 of the outer packaging material 20 where the outer packaging materials 20 are bonded to each other. The outer packaging material 20 of the outer packaging material 20 when the two vacuum heat insulating materials 10 are viewed in plan, as compared with the case where the end portions 12 of the 20 outer packaging materials 20 bonded together are arranged without being bent. The area ratio occupied by the end portions 12 bonded to each other is reduced. However, when the bent portion 13 is formed, the bent portion 14 that is the base portion of the end portion 12 on the core material 1 side, or the corner portion 15 of the outer packaging material 20 that covers the shoulder portion of the core material 1. Since tensile / compressive stress is also applied to the barrier layer, cracks are easily generated in the bent portion 14 and the corner portion 15 as well as the bent portion 13, and the vacuum degree of the vacuum heat insulating material 10 is reduced. There is a problem such as.

  According to the present invention, since the outer packaging material has a value of the function M equal to or less than a predetermined value, the outer packaging materials are bonded together when using the vacuum heat insulating material formed using the outer packaging material. Occurrence of cracks in the barrier layer at bent portions formed by bending the end portions, bent portions at the end portions, corner portions of the outer packaging material, and the like can be suppressed. Therefore, the outer packaging material can form a vacuum heat insulating material capable of maintaining the heat insulating performance for a long time. Here, the reason why the occurrence of cracks in the barrier layer in the bent portion or the like can be suppressed when the value of the function M is equal to or less than a predetermined value is estimated as follows.

That is, with respect to the amount of deformation when stress is applied to an object, the object has a property of tensile elastic modulus E, the shape is a cuboid having a width b and a thickness h, and the position where the stress F is applied is a cuboid. In the case of a position at a distance L from the end that supports the shaped object, the deformation amount v is generally represented by v = 4FL ³ / (bEh ³ ). On the other hand, the function M, which is the product of the tensile modulus E of the outer packaging material and the cube of the thickness h of the outer packaging material, is expressed by M = Eh ³ and is inversely proportional to the deformation amount v. There is a relationship. For this reason, as the value of the function M is smaller, the amount of deformation when the same stress is applied becomes larger and becomes an index of the softness of the outer packaging material. Therefore, the value of the function M being equal to or less than a predetermined value indicates that the outer packaging material has a predetermined flexibility.

  Further, as described above, when the value of the function M is equal to or less than a predetermined value, the bent portion is bent when the outer packaging material is bent as compared with a value of the function M that is larger than a predetermined value. In addition, the number of wrinkles formed substantially in parallel with the direction along the formation direction of the bent portion increases. Therefore, when the value of the function M is larger than a predetermined value and the outer packaging material is a hard material, the outer packaging material cannot be bent unless a strong stress is applied, and the barrier layer If there is even one weak point, stress concentrates and cracks occur at one point to bend, whereas the value of the function M is equal to or less than a predetermined value, In the case of a soft material, since the outer packaging material can be bent with a small stress, even if there is a weak portion in the barrier layer, the outer layer can be bent in other portions without stress concentration in the weak portion. It is possible to disperse the stress concentration. When the value of the function M is smaller than a predetermined value, the stress is dispersed at a plurality of locations and bending occurs at many locations. As a result, the number of wrinkles formed at the bent portion is the value of the function M. Is larger than a value larger than a predetermined value.

  In addition, as illustrated in FIG. 3, when the number of bent portions (wrinkles) 13 a in the bent portion 13 is small compared to the case where the bent portions (wrinkles) 13 a in the bent portion 13 are small (FIG. 3A). (FIG. 3B) shows that the bending angle α at each bent portion (wrinkle) 13a is small, and as a result, the stress applied to the barrier layer at each bent portion (wrinkle) is reduced. Can do. From this point of view as well, the occurrence of cracks in the barrier layer at the bent portion or the like can be suppressed.

From the above viewpoint, in the present invention, an outer packaging material having a value of the function M of 3.0 MPa · mm ³ or less is used. The value of the function M, that is, the product of the tensile modulus of the outer packaging material and the cube of the thickness of the outer packaging material is not particularly limited as long as it is 3.0 MPa · mm ³ or less. it is preferably in the range of ^{5MPa · mm 3 ~2.5MPa · mm 3} , among ^them, preferably in the range of ^{0.5MPa · mm 3 ~2.0MPa · mm 3} , in particular, 0.5 MPa · It is preferable to be in the range of mm ^{3 to} 1.0 MPa · mm ³ . This is because the occurrence of cracks in the barrier layer can be more effectively suppressed when the value of the function M is within the above range.

The tensile elastic modulus of the outer packaging material is not particularly limited as long as the value of the function M can be a predetermined value or less, but is preferably in the range of 1500 MPa to 5000 MPa. However, it is preferably in the range of 2000 MPa to 4000 MPa, and particularly preferably in the range of 2500 MPa to 3500 MPa. This is because it is easy to set the value of the function M to a predetermined value or less. The tensile modulus was measured in accordance with JIS K7161, after the outer packaging material was cut into a strip shape having a width of 15 mm and a length of 120 mm, and then a distance between chucks of 100 mm and a tensile speed of 100 mm / A method of measuring the tensile modulus in min can be used. The tensile elastic modulus can be measured at 23 ° C. and 55% humidity. As the tensile tester, for example, a tensile tester (Tensilon universal tester RTC-1250A) can be used.
Moreover, the said tensile elastic modulus is performed using a minimum of 5 test pieces, and the average value of the obtained 5 or more tensile elastic moduli can be used. Furthermore, the said tensile elasticity modulus is the average value of each tensile elasticity modulus of a longitudinal direction (winding direction) and the transversal direction (width direction) orthogonal to a longitudinal direction, when the said outer packaging material is elongate. Can be used.

  The thickness of the outer packaging material in the function M refers to the thickness of the outer packaging material per sheet. For example, the function of the outer packaging material in the vacuum heat insulating material formed using two outer packaging materials. The thickness used for the calculation of M refers to the thickness of the single outer packaging material.

  From the above viewpoint, among the various layer configurations described above, in the present invention, the thermal welding layer is a layer mainly composed of polybutylene terephthalate, the barrier layer is an aluminum foil layer, and the protective layer. Is preferably a layer mainly composed of polyethylene terephthalate. By forming a vacuum heat insulating material using an outer packaging material having a layer structure of the above combination, the value of the function M of the outer packaging material can be reduced, and by bending an end portion where the outer packaging materials are bonded together It is because it can be set as the vacuum heat insulating material which can suppress generation | occurrence | production of the crack to the said barrier layer in the bending part etc. which are formed, and can maintain heat insulation performance for a long period of time.

(2) Others The outer packaging material may have a plurality of protective layers or barrier layers. In the outer packaging material, for example, two or more barrier layers may be provided between the heat-welded layer and the protective layer, and the first protective layer and the second protective layer are provided on the heat-welded layer and the barrier layer. Two or more protective layers may be provided. Further, the outer packaging material may be provided with an inner surface side protective layer between the heat welding layer and the barrier layer. The outer packaging material may have an arbitrary layer such as an anchor coat layer or a pinhole-resistant layer. Furthermore, in the present invention, it is preferable that the outer packaging material does not include the inner surface side protective layer between the thermal welding layer and the barrier layer. This is because the layer structure of the outer packaging material can be reduced, and the value of the function M can be easily set to a predetermined value or less.

  The outer packaging material may or may not have transparency, and can be appropriately set according to the use of the vacuum heat insulating material for which the outer packaging material is used. The transparency of the outer packaging material is not defined by a strict transmittance, and can be appropriately determined according to the application. When the outer packaging material has transparency, it is possible to visually recognize the inside of the vacuum heat insulating material by using it as a vacuum heat insulating material. It is possible to visually confirm the vacuum state.

  The tensile elastic modulus of the two layers sandwiching the barrier layer adjacent to the outer packaging material is not particularly limited as long as the value of the function M is a predetermined value or less, but is 1.0 GPa. It is preferable to be in the range of ˜5.0 GPa, in particular, it is preferably in the range of 1.5 GPa to 5.0 GPa, particularly preferably in the range of 2.0 GPa to 4.5 GPa. The difference in tensile elastic modulus between the barrier layer and the two layers sandwiching the barrier layer is reduced by making the tensile elastic modulus of the two layers sandwiching the barrier layer adjacent to each other within the above range. As a result, the occurrence of cracks in the barrier layer can be more effectively suppressed.

  Note that the two layers sandwiching the barrier layer adjacent to each other specifically include a thermal welding layer and a protective layer when the outer packaging material has a layer configuration of a thermal welding layer / barrier layer / protective layer. In the case where the outer packaging material has a layer structure of a thermal welding layer / barrier layer / first protective layer / second protective layer, the outer packaging material refers to the thermal welding layer and the first protective layer. In the case where the material has a layer structure of a heat-welded layer / an inner surface protective layer / a barrier layer / a protective layer, it means an inner surface protective layer and a protective layer. The two layers sandwiching the barrier layer adjacent to each other do not include an interlayer adhesive that bonds the barrier layer to each layer.

  The thickness of the outer packaging material is not particularly limited as long as the value of the function M can be a predetermined value or less, but is preferably in the range of 30 μm to 200 μm, for example, It is preferably within the range of 50 μm to 150 μm.

  The tensile strength of the outer packaging material is preferably 50 N or more, and more preferably 80 N or more. This is because breakage or the like is less likely to occur when the vacuum heat insulating material formed using the outer packaging material of the present invention is bent. The tensile strength is a value measured based on JIS-Z-1707.

  The method of laminating the outer packaging material is not particularly limited as long as it is a method that can laminate each layer so that one outermost layer has a protective layer and the other outermost layer has a heat-welded layer, A known method can be used. Examples of the laminating method include a dry lamination method in which each layer formed in advance is bonded using the above-described interlayer adhesive.

IV. Vacuum heat insulating material The heat conductivity of the vacuum heat insulating material is preferably low. For example, the heat conductivity of the vacuum heat insulating material at 25 ° C. (initial heat conductivity) is preferably 10 mW / m · K or less, Among them, it is preferably 7 mW / m · K or less, and particularly preferably 5 mW / m · K or less. This is because by setting the heat conductivity of the vacuum heat insulating material within the above range, the vacuum heat insulating material is less likely to conduct heat to the outside, and therefore, a high heat insulating effect can be achieved.

  The vacuum heat insulating material has an increase in the thermal conductivity of the vacuum heat insulating material of 2 mW / m · K or less with respect to the initial heat conductivity after being left to stand in an environment of 130 ° C. for 1000 hours. Among these, 1.5 mW / m · K or less is preferable. This is because the vacuum heat insulating material in which the increase in the thermal conductivity is within the above range can maintain the heat insulating performance for a long time. In addition, the said heat conductivity can be made into the value measured by the heat flow meter method using the heat conductivity measuring apparatus according to JIS-A-1412-3. Examples of the thermal conductivity measuring device include a thermal conductivity measuring device Auto Lambda (product name HC-074, manufactured by Eihiro Seiki Co., Ltd.).

  The vacuum heat insulating material of this invention seals the inside enclosed with the said outer packaging material for vacuum heat insulating materials under reduced pressure, and makes it the vacuum state. The degree of vacuum inside the vacuum heat insulating material is preferably 5 Pa or less. By setting the degree of vacuum inside the vacuum heat insulating material within the above range, heat conduction due to convection of air remaining inside can be reduced, and excellent heat insulation can be exhibited.

  The vacuum heat insulating material preferably has high barrier performance. This is because it is possible to prevent a decrease in the degree of vacuum due to intrusion of moisture, oxygen, and the like from the outside. The barrier performance of the vacuum heat insulating material is the same as the oxygen permeability and water vapor permeability described in the above-mentioned sections of “III. Outer packaging material for vacuum heat insulating material, 3. Barrier layer”. Omitted.

V. Manufacturing method As a manufacturing method of the vacuum heat insulating material of this invention, a general method can be used. For example, the outer packaging material of the present invention described above is prepared in advance, the two outer packaging materials are opposed to each other so that the respective heat-welded layers face each other, the core material is disposed therebetween, and the above-mentioned by a bag making machine or the like. Prepare a bag body that is formed of the two outer packaging materials by placing one of the outer circumferences of the core material as an opening and heat-welding the ends of the remaining three outer packaging materials, and in which the core material is arranged. Then, the bag body is attached to a vacuum sealing machine, and the opening is sealed in a state where the internal pressure of the bag body is reduced, whereby the core material is sealed with the outer packaging material. Is obtained.

  Further, in the above manufacturing method, one outer packaging material is opposed so that the heat-welded layer faces inward, the core material is disposed therebetween, and one of the outer circumferences of the core material is opened by a bag making machine or the like. Then, by heat-welding the ends of the remaining two outer packaging materials, a bag body formed of one outer packaging material and having the core material disposed therein is prepared, and then the bag body Even in a method of obtaining a vacuum heat insulating material in which the core material is enclosed by the outer packaging material by sealing the opening in a state where the internal pressure of the bag body is reduced, while mounting the vacuum sealing machine. good.

VI. Applications The vacuum heat insulating material of the present invention has low thermal conductivity and is excellent in heat insulating properties and durability even at high temperatures. Therefore, the said vacuum heat insulating material can be used for the site | part which has a heat source and generate | occur | produces heat | fever, or the site | part which becomes high temperature by being heated from the outside. Applications of the present invention include, for example, equipment described in “B. Equipment with Vacuum Insulation”, cooler box, transportation container, fuel tank such as hydrogen, system bath, hot water tank, heat insulation box, residential wall, automobile, An airplane, a ship, a train, etc. are mentioned.

B. Next, the apparatus with a vacuum heat insulating material of the present invention will be described. The device with a vacuum heat insulating material of the present invention is a device having a heat source part or a heat retaining portion in the main body or inside, and a device with a vacuum heat insulating material provided with at least a vacuum heat insulating material, wherein the vacuum heat insulating material is a core material, An outer packaging material for a vacuum heat insulating material that encloses the core material, the core material contains an inorganic fiber aggregate, and an adsorbent is disposed inside the outer packaging material for the vacuum heat insulating material, and the vacuum The outer packaging material for heat insulating material has a heat-welded layer, a barrier layer, and a protective layer in this order, and is a product of the tensile elastic modulus of the outer packaging material for vacuum heat insulating material and the cube of the thickness of the outer packaging material for vacuum heat insulating material. However, it is 3.0 MPa · mm ³ or less, and each layer of the outer packaging material for a vacuum heat insulating material is arranged via a polyester-based interlayer adhesive.

  Here, the “heat source section” refers to a portion that generates heat in the device main body or inside the device when the device itself is driven, and refers to, for example, a power source or a motor. The “insulated part” refers to a part that does not have a heat source part in the apparatus main body or inside, but the apparatus is heated by receiving heat from an external heat source.

  According to the present invention, the vacuum heat insulating material is the above-described vacuum heat insulating material of the present invention, and can maintain heat insulating performance for a long period of time. In the device having the heat retaining portion, the temperature of the heat retaining portion can be maintained by the vacuum heat insulating material. Thereby, it can be set as the apparatus which has the high energy saving characteristic which suppressed power consumption.

  About the vacuum heat insulating material in this invention, since it is the same as that of the content demonstrated by the term of the "A. vacuum heat insulating material" mentioned above, description here is abbreviate | omitted.

  The device in the present invention has a main body or a heat source part or a heat-retained part inside the main body. What has is preferable. Examples of the device in the present invention include, for example, natural refrigerant heat pump water heater (registered trademark “Ecocute”), refrigerator, vending machine, rice cooker, pot, microwave oven, commercial oven, IH cooking heater, electrical appliances such as OA equipment, Examples include automobiles. Especially in this invention, the said apparatus is a natural refrigerant | coolant heat pump water heater, a commercial oven, a microwave oven, and a motor vehicle, It is preferable to use the above-mentioned vacuum heat insulating material of this invention for these apparatuses.

  As an aspect of mounting the vacuum heat insulating material on a device, a vacuum heat insulating material may be directly attached to a heat source portion or a heat retaining portion of the device, and a vacuum heat insulating material between the heat retaining portion and the heat source portion or an external heat source. It may be mounted so as to sandwich it.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

  The present invention will be described more specifically with reference to the following examples.

[Example 1]
(Preparation of outer packaging material for vacuum insulation)
An outer packaging material having a layer structure of a heat welding layer / barrier layer / protective layer was produced. PET film (thickness: 16 μm) with PBT film (thickness: 30 μm, manufactured by Aussie Film Co., Ltd.) as a thermal welding layer, aluminum foil (thickness: 6 μm, product name: 1N-30, manufactured by UACJ Foil Co., Ltd.) as a barrier layer. , Product name: PTMB, manufactured by Unitika Ltd.) was used as a protective layer. For each of the above layers, an interlayer adhesive (product name: LX500 / KR-90S, manufactured by DIC Graphics Co., Ltd.) is used on the surface of the lower layer, and a die coater is used so that the coating amount is 3.5 g / m ^2. It was coated and dried, and laminated by laminating the upper layer.

(Preparation of vacuum insulation)
Two sheets of the obtained outer packaging material were stacked and heat sealed in the three directions of the rectangle to create a bag body opened in only one direction. 300 mm × 300 mm × 30 mm glass wool was used as the core material, and after drying treatment (at 145 ° C. for 1 hour), the core material and the adsorbent were housed in the bag body, and the inside of the bag body was evacuated. . Then, the opening part of the said bag body was sealed by heat sealing, and the vacuum heat insulating material was obtained. The sealing pressure was 0.05 Pa.

[Example 2]
An outer packaging material having a layer structure of a thermal welding layer / barrier layer / protective layer 2 / protective layer 1 was produced. A PET film (thickness: 12 μm, product name: E5100, manufactured by Toyobo Co., Ltd.) was used as the protective layer 1, and a nylon film (thickness: 25 μm, product name: Harden film N1102, manufactured by Toyobo Co., Ltd.) was used as the protective layer 2. Except for the above, an outer packaging material was produced in the same manner as in Example 1, and a vacuum heat insulating material was produced in the same manner as in Example 1 using the obtained outer packaging material.

[Comparative Example 1]
An outer packaging material was prepared in the same manner as in Example 2 except that an adhesive (product name: LX-605 / KW40, manufactured by DIC Graphics Co., Ltd.) was used as an interlayer adhesive, and the obtained outer packaging material was used. In the same manner as in Example 1, a vacuum heat insulating material was produced.

[Example 3]
An outer packaging material was prepared in the same manner as in Example 1 except that glass wool 300 × 300 × 30 mm with a binder was used as the core material, and a vacuum was applied in the same manner as in Example 1 using the obtained outer packaging material. A heat insulating material was produced.

[Evaluation]
The time-dependent change of the heat conductivity in 130 degreeC of the vacuum heat insulating material obtained in Examples 1-3 and the comparative example 1 was measured. The heat conductivity of each vacuum heat insulating material can be made into the value measured by the heat flow meter method using the heat conductivity measuring apparatus according to JIS-A-1412-3. As the thermal conductivity measuring device, a thermal conductivity measuring device Auto Lambda (product name HC-074, manufactured by Eihiro Seiki Co., Ltd.) was used. The measurement results are shown in FIGS.

  From the measurement result of the temporal change in the thermal conductivity of the vacuum heat insulating material in FIG. 4, the layer structure of the outer packaging material is PBT / aluminum foil / PET, and Example 1 using a polyester-based adhesive as an interlayer adhesive is It can be seen that there is very little change in conductivity over time. Although the layer structure of the outer packaging material is the same as in Example 2, it can be seen that Comparative Example 1 using an epoxy adhesive as an interlayer adhesive has a larger change in thermal conductivity with time than Example 2.

  Further, from the measurement result of the temporal change of the thermal conductivity of the vacuum heat insulating material in FIG. 5, it can be seen that Example 1 using the core material containing no binder has very little change of the thermal conductivity with the passage of time. Even though the layer structure of the outer packaging material is the same, Example 1 using the core material containing no binder has a smaller change in thermal conductivity over time than Example 3 using the core material with the binder. I understand.

[Reference Example 1]
(Production of outer packaging material)
As the second protective layer, the same interlayer adhesive as in Example 1 was applied to the easy-adhesion surface of a nylon film (ON35, thickness: 35 μm, product name: Emblem ONBC, manufactured by Unitika Ltd.) that was subjected to easy-adhesion treatment on both sides. It apply | coated and dried using the die-coater so that it might become a coating amount 3.5g / m < ² >. Thereafter, a PET film (PET12, thickness: 12 μm, product name: E5100, manufactured by Toyobo Co., Ltd.) whose both surfaces are easily bonded as a first protective layer is laminated on the surface of the second protective layer to which the interlayer adhesive is applied. did.
Next, an interlayer adhesive was similarly applied at a coating amount of 3.5 g / m ² on the PET12 (first protective layer) surface of the obtained two-layer film and dried. As the barrier layer, Al foil (AL6, thickness: 6 μm, product name: 1N-30, manufactured by UACJ Foil Co., Ltd.) was laminated on the surface of the first protective layer to which the interlayer adhesive was applied.
Subsequently, an interlayer adhesive was similarly applied to the AL6 (barrier layer) surface of the obtained three-layer film at an application amount of 3.5 g / m ² and dried. As an inner surface side protective layer, PET12 was laminated on the surface of AL6 (barrier layer) coated with an interlayer adhesive.
Next, an interlayer adhesive was similarly applied to the obtained PET 12 (inner surface side protective layer) surface of the four-layer film at a coating amount of 3.5 g / m ² and dried. An unstretched polypropylene (CPP50, thickness: 50 μm, product name: 3301, manufactured by Toray Film Processing Co., Ltd.) is laminated on the surface of PET 12 (inner surface protective layer) coated with an interlayer adhesive as a heat-welded layer, and an outer packaging material Got.

[Reference Example 2]
An outer packaging material in the same manner as in Reference Example 1 except that a nylon film (ON25, film thickness: 25 μm, product name: ONM, manufactured by Unitika Co., Ltd.) with easy adhesion treatment on both sides was used as the second protective layer. Got.

[Reference Example 3]
Except for forming the second protective layer and using unstretched polypropylene (CPP30, thickness: 30 μm, product name: 3301, manufactured by Toray Film Processing Co., Ltd.) as the heat-welding layer, the outer packaging was similar to Reference Example 1. The material was obtained.

[Reference Example 4]
An outer packaging material was obtained in the same manner as in Reference Example 3 except that polybutylene terephthalate (PBT25, thickness: 25 μm, product name: Emblet, manufactured by Unitika Ltd.) was used as the heat welding layer.

[Reference Example 5]
Similar to Reference Example 4, except that a corona-treated nylon film (ON15, thickness: 15 μm, product name: N-1200, manufactured by Toyobo Co., Ltd.) was used as the first protective layer and the inner surface side protective layer. The outer packaging material was obtained.

[Reference Example 6]
Similar to Reference Example 4 except that a PET film (PET 16, thickness: 16 μm, product name: PTMB, manufactured by Unitika Ltd.) whose both surfaces were subjected to easy adhesion treatment was used as the first protective layer, and the inner surface side protective layer was not formed. Thus, an outer packaging material was obtained.

[Reference Example 7]
An outer packaging material was obtained in the same manner as in Reference Example 6 except that ON25 was used as the first protective layer.

[Reference Example 8]
An outer packaging material was obtained in the same manner as in Reference Example 5 except that a linear short-chain branched polyethylene (LLDPE30, thickness: 30 μm, product name: TUX-HCE, manufactured by Mitsui Chemicals, Inc.) was used as the heat welding layer. .

[Reference Example 9]
An outer packaging material was obtained in the same manner as in Reference Example 8 except that ON25 was used as the first protective layer and the inner surface side protective layer.

[Reference Example 10]
An outer packaging material was obtained in the same manner as in Reference Example 9 except that PET12 was used as the first protective layer and the inner surface side protective layer.

[Evaluation in Reference Example]
The calculation of the function M and the evaluation of the barrier properties of the outer packaging materials obtained in Reference Examples 1 to 10 were performed, and the tensile elastic modulus of each material used for forming the outer packaging material was measured.

(Calculation of the function M of the outer packaging material)
About the outer packaging material obtained by the said reference examples 1-10, thickness and the tensile elasticity modulus were measured and the value of the function M was calculated. The results are shown in Table 1 below. FIG. 6 shows a graph showing the relationship between the value of the function M of the outer packaging material and the oxygen barrier property result obtained by “barrier property evaluation” described later. In addition, the measuring method of the tensile elastic modulus of the outer packaging material is based on JIS K7161, and after cutting the outer packaging material into a strip shape having a width of 10 mm and a length of 120 mm, a tensile tester is used at 23 ° C. and a humidity of 55%. The tensile elastic modulus was measured using a Tensilon universal testing machine RTC-1250A at a distance between chucks of 100 mm and a tensile speed of 100 mm / min. Moreover, the said tensile elasticity modulus was made into the average value of each tensile elasticity modulus of the longitudinal direction and the transversal direction of the said outer packaging material.

(Barrier performance evaluation)
The outer packaging materials obtained in Reference Examples 1 to 10 above were subjected to bending treatment three times by a gelbo flex tester, and then measured by MOCON, USA, under conditions of a temperature of 23 ° C. and a humidity of 60% RH. The oxygen permeability was measured and evaluated with a machine [model name, OX-TRAN]. The results are shown in Table 1 below.

(Measurement of tensile modulus of material of outer packaging material)
The method for measuring the tensile elastic modulus of the outer packaging material described in the above section “Calculation of the function M of the outer packaging material” for ON35, PET12, CPP30, PBT25, and LLDPE30 used in the formation of the outer packaging material in Reference Examples 1 to 10 above The tensile modulus was measured using the same method. The results are shown in Table 2 below.

(Summary)
From Table 1, it was confirmed that in Reference Examples 2 to 10 in which the value of the function M was 3.0 MPa · mm ³ or less, the oxygen barrier property was excellent. Further, from the comparison of Reference Example 4 and Reference Example 6 and the like, the use of a heat-welded layer having a tensile modulus of 1.0 GPa or more reduces the layer structure of the outer packaging material in a state in which cracks are suppressed. I can confirm that I can do it.

DESCRIPTION OF SYMBOLS 1 ... Core material 2 ... Thermal welding layer 3 ... Barrier layer 4 ... Protective layer 5 ... Interlayer adhesive 6 ... Adsorbent 10 ... Vacuum heat insulating material 12 ... End part 13 ... Bending part 14 ... Bending part 15 ... Corner part 20 ... Vacuum Insulation outer packaging

Claims (4)

A vacuum heat insulating material having a core material and a vacuum heat insulating material encapsulating the core material,
The core material contains an inorganic fiber aggregate,
An adsorbent is arranged inside the outer packaging material for vacuum heat insulating material,
The outer packaging material for a vacuum heat insulating material has a heat welding layer, a barrier layer and a protective layer in this order,
The product of the tensile elastic modulus of the vacuum insulation material and the cube of the thickness of the vacuum insulation material is 3.0 MPa · mm ³ or less,
Each layer of the vacuum insulating material outer packaging material is disposed via a polyester-based interlayer adhesive. The thermal welding layer is a layer mainly composed of polybutylene terephthalate,
The barrier layer is an aluminum foil layer;
The vacuum heat insulating material according to claim 1, wherein the protective layer is a layer mainly composed of polyethylene terephthalate.   The increase in the thermal conductivity of the vacuum heat insulating material after being allowed to stand in an environment of 130 ° C. for 1000 hours with respect to the initial thermal conductivity of the vacuum heat insulating material is 2 mW / m · K or less. The vacuum heat insulating material according to claim 1 or 2. A device having a heat source part or a heat-retained part in the main body or inside, and a device with a vacuum heat insulating material comprising at least a vacuum heat insulating material,
The vacuum heat insulating material has a core material and an outer packaging material for a vacuum heat insulating material that encloses the core material,
The core material contains an inorganic fiber aggregate,
An adsorbent is arranged inside the outer packaging material for vacuum heat insulating material,
The outer packaging material for a vacuum heat insulating material has a heat welding layer, a barrier layer and a protective layer in this order,
The product of the tensile elastic modulus of the vacuum insulation material and the cube of the thickness of the vacuum insulation material is 3.0 MPa · mm ³ or less,
Each layer of the vacuum insulating material outer packaging material is disposed via a polyester-based interlayer adhesive, and a device with a vacuum insulating material.