JP2022057321A - Heat-insulating holding laminate - Google Patents

Abstract

To provide a heat-insulating holding laminate for a vacuum heat-insulating panel outer packaging material, a heat-insulating holding packaging material, and a heat-insulating holding package which adsorb gas generated from a sealant layer itself and a gas from a space in contact with the sealant layer, have a sealant layer having a small amount of gas discharge, suppress rise in an atmospheric pressure in an internal depressurized condition inside a vacuum heat-insulating panel due to degradation with time, and suppress rise of thermal conductivity in a thickness direction of the vacuum heat-insulating panel.SOLUTION: A heat-insulating holding laminate 1 has a gas barrier base material layer 3, and a low gas dischargeable gas adsorption sealant layer 4, in which the low gas dischargeable gas adsorption sealant layer contains a low gas dischargeable resin having heat sealability, a gas adsorbent 6a and a moisture absorbent 6b, and the low gas dischargeable resin has a density of 0.915 g/cm3 or more and 0.935 g/cm3 or less.SELECTED DRAWING: Figure 1

Description

The present invention has a heat insulating property for a vacuum heat insulating panel outer packaging material having a sealant layer that adsorbs a gas generated from the sealant layer itself and a gas containing water (water vapor) from a space in contact with the sealant layer and has a small amount of outgassing. Regarding the holding laminate.

The vacuum insulation panel has a structure in which the internal structure in which the core material is arranged is sealed with an outer packaging material, and the pressure inside the vacuum insulation panel is much lower than the atmospheric pressure, and is maintained in a reduced pressure state close to vacuum. ..
Since heat convection is suppressed by the decompression state inside the vacuum insulation panel, the vacuum insulation panel can exhibit good insulation performance in the thickness direction, and the insulation performance per unit thickness of the vacuum insulation panel is Higher than general foam insulation. Further, since the heat insulating efficiency is high, the vacuum heat insulating panel can reduce the thickness of the vacuum heat insulating panel while ensuring the desired heat insulating property.
Therefore, by manufacturing the heat insulating container using the vacuum heat insulating panel, it is possible to reduce the weight and space of the heat insulating container.
However, when the internal air pressure of the vacuum heat insulating panel rises due to breakage or deterioration over time and the reduced pressure state is impaired, the heat insulating performance of the vacuum heat insulating panel deteriorates sharply.
Conventionally, the reason for the increase in internal air pressure due to deterioration over time due to the outer packaging material is the intrusion of air due to the permeation of air through the outer packaging material. A laminated film having a metal aluminum foil of a certain thickness as a gas barrier layer has been mainly used, and a laminated film further having a layer composed of a vapor-deposited film or a coating film of various inorganic substances has been proposed (Patent Document 1). However, it was insufficient in terms of maintaining stable heat insulating properties over the long term.
A method of maintaining the degree of vacuum inside the packaging by adsorbing a gas component by containing a porous body such as synthetic zeolite in the sealant layer of the packaging material has also been proposed (Patent Document 2), but the type of gas to be adsorbed. However, it was insufficient in terms of maintaining a stable heat insulating effect for a long period of time due to the limited heat resistance of the resin constituting the sealant layer and the large amount of outgas generated. ..

Japanese Unexamined Patent Publication No. 2008-08717 Japanese Unexamined Patent Publication No. 2018-189220

The present invention has a sealant layer that adsorbs a gas generated from the sealant layer itself and a gas containing water (steam) from a space in contact with the sealant layer and releases a small amount of gas, and has a vacuum insulation panel inside due to deterioration over time. Insulation retention laminate for vacuum insulation panel outer packaging material, insulation retention packaging material, insulation retention The subject is to provide a package.

As a result of various studies, the present inventors have found that at least a heat insulating retaining laminate having a small amount of gas emission and gas adsorptivity including water (water vapor) adsorptivity achieves the above object. ..
That is, the present invention is characterized by the following points.
1. 1. A heat insulating retaining laminate for a vacuum heat insulating panel that adsorbs a gas generated from the sealant layer itself and a gas from a space in contact with the sealant layer.
The gas is one or a combination of two or more selected from the group consisting of hydrocarbons, aldehydes, ketones, carboxylic acids, esters, alcohols, carbon dioxide, and water vapor.
The heat insulating retaining laminate has a gas barrier base material layer and an outgassing gas adsorption sealant layer.
The low gas-releasing gas-adsorbing sealant layer contains a low-gas-releasing resin having a heat-sealing property, a gas adsorbent, and a hygroscopic agent.
The low outgassing resin is a heat insulating retaining laminate having a density of 0.915 g / cm ³ or more and 0.935 g / cm ³ or less.
2. 2. The content of the low gas-releasing resin is 70% by mass or more and 99.9% by mass or less in the total low gas-releasing gas adsorption sealant layer.
The content of the gas adsorbent is 0.1% by mass or more and 30% by mass or less in the layer containing the gas adsorbent.
The content of the hygroscopic agent is 1% by mass or more and 50% by mass or less in the layer containing the hygroscopic agent.
The heat insulating retaining laminate according to 1 above.
3. 3. The heat insulating retaining laminate according to 1 or 2 above, wherein the low outgassing resin is a polyethylene-based resin.
4. Any of the above 1 to 3, wherein the concentration of the elution total organic carbon (TOC) contained in the film made of the low outgassing resin is 1.5 ppm or more and 250 ppm or less. The heat insulating retaining laminate according to the above.
5. Any of the above 1 to 4, wherein the low gas-releasing resin is one or a combination of two or more selected from the group consisting of medium-density polyethylene, low-density polyethylene, and linear low-density polyethylene. The heat insulating retaining laminate described in 1.
6. Any of the above 1 to 5, wherein the gas adsorbent contains one or a combination of two or more selected from the group consisting of hydrophobic zeolite, molecular sieve, metal-organic framework (MOF), and activated carbon. The heat insulating retaining laminate described in Crab.
7. The heat insulating agent according to any one of 1 to 6 above, wherein the hygroscopic agent is one or a combination of two or more selected from the group consisting of calcium oxide, magnesium oxide, barium oxide, and hydrophilic zeolite. Sex-retaining laminate.
8. The low gas-releasing gas adsorption sealant layer has an adsorption layer and a heat seal layer.
The adsorption layer is a layer containing the low gas-releasing resin, the gas adsorbent, and the hygroscopic agent.
The heat-sealing layer is a layer containing the low gas-releasing resin and having a heat-sealing property.
The outermost layer on at least one side of the low gas outgassing gas adsorption sealant layer is a heat seal layer.
The low outgassing resin contained in the adsorption layer and the low outgassing resin contained in the heat seal layer are the same or different from each other.
The heat insulating retaining laminate according to any one of 1 to 7 above.
9. The heat insulating retaining laminate according to 8 above, wherein the adsorption layer is composed of a gas adsorption layer and a hygroscopic layer.
10. The heat insulating retaining laminate according to any one of 1 to 9 above, wherein the low gas outgassing gas adsorption sealant layer further contains an antioxidant.
11. 10. The heat insulating property retention according to 10 above, wherein the content of the antioxidant is 0.005% by mass or more and 0.5% by mass or less in the total low gas outgassing gas adsorption sealant layer. Laminated body.
12. The antioxidant is contained in the adsorption layer and / or the heat seal layer.
The antioxidant contained in the adsorption layer and the antioxidant contained in the heat seal layer are the same or different.
The heat insulating retaining laminate according to any one of 9 to 11 above.
13. The heat insulating retaining laminate according to any one of 1 to 12 above, wherein the low gas-releasing gas-adsorbed sealant layer is a layer made of a low-gas-releasing gas-adsorbed sealant film.
14. In the low gas outgassing gas adsorption sealant film, the amount of the organic gas component having 16 carbon atoms released when heated in air at 90 ° C. for 60 minutes is the amount per unit volume of the low gas outgassing gas adsorption sealant film. The heat insulating retaining laminate according to 13 above, characterized in that it is 10 μg / cm ³ or more and 1000 μg / cm ³ or less.
15. A heat insulating holding packaging material for a vacuum heat insulating panel, which is produced by using the heat insulating holding laminate according to any one of 1 to 14.
16. A vacuum heat insulating panel manufactured by using the heat insulating retaining packaging material according to the above 15.

INDUSTRIAL APPLICABILITY According to the present invention, there is a sealant layer that adsorbs a gas generated from the sealant layer itself and a gas containing water (steam) from a space in contact with the sealant layer, and has a small amount of outgassing, and the inside of a vacuum insulation panel due to deterioration over time. Insulation retention laminate for vacuum insulation panel outer packaging material, insulation retention packaging material, insulation retention A package can be obtained.

It is a schematic sectional drawing which shows an example of the layer structure of the heat insulating holding laminate or the heat insulating holding packaging material of this invention. It is a schematic sectional drawing which shows an example of another aspect of the layer structure of the heat insulating holding laminate or the heat insulating holding packaging material of this invention. It is a schematic sectional drawing which shows an example of another aspect of the layer structure of the heat insulating holding laminate or the heat insulating holding packaging material of this invention. It is a schematic sectional drawing which shows an example of still another aspect of the layer structure of the heat insulating holding laminate or the heat insulating holding packaging material of this invention. It is a schematic sectional drawing which shows an example of the structure of the heat insulating holding package (vacuum heat insulating panel) of this invention.

In each figure, the size and ratio of the members may be changed or exaggerated for the sake of clarity. In addition, for the sake of readability, unnecessary parts for explanation and repeated codes may be omitted.
Further, although omitted in each figure, an adhesive layer may be provided between the layers.
Furthermore, if necessary, in order to strengthen the adhesive strength (adhesion strength) between the layers, the laminated surface of each layer is physically subjected to corona discharge treatment, ozone treatment, plasma treatment, glow discharge treatment, sandblast treatment, etc. It is also possible to perform a chemical surface treatment such as a specific surface treatment or an oxidation treatment using a chemical in advance.

The heat insulating holding laminate, the heat insulating holding packaging material, and the heat insulating holding package of the present invention will be described in more detail below. The present invention will be described with reference to specific examples, but the present invention is not limited thereto.
In the present invention, the film and the sheet are treated as synonymous.

≪Heat insulation retaining laminate≫
The heat insulating retaining laminate of the present invention is a laminated body used as an outer packaging material of a vacuum heat insulating panel, and has a layer structure having a gas barrier base material layer and a low gas outgassing gas adsorption sealant layer.
The low gas outgassing sealant layer contains a low outgassing resin, a gas adsorbent, and a hygroscopic agent, and the outgassing resin is a low outgassing resin having a heat seal property. Is preferable.

The inside of the vacuum insulation panel is often decompressed to 0.1 to 100 Pa, depending on the application. The vacuum heat insulating panel packaged by the heat insulating holding laminate of the present invention maintains the heat insulating property in the thickness direction by maintaining the internal air pressure in a reduced pressure state for a long period of time.
Regarding the heat insulation sustainability of the vacuum heat insulating panel, for example, the increase in thermal conductivity of the vacuum heat insulating panel after storage in a 100 ° C environment for 1000 hours is preferably 0 mW / mK or more and 7.0 mW / mK or less, preferably 0 mW. It is more preferably / mK or more and 6.5 mW / mK or less. Most preferably, there is no increase in thermal conductivity, and those exceeding the above range tend to be inferior in practicality over a long period of time.

In order to maintain the decompression state inside the vacuum insulation panel, it is necessary to suppress the increase of gas molecules inside the vacuum insulation panel, and for that purpose, the gas released from the outer packaging material of the vacuum insulation panel itself. Suppresses the amount of gas that permeates in the thickness direction of the outer packaging material and enters the inside of the vacuum insulation panel, the amount of gas that penetrates the inside of the vacuum insulation panel along the interface of the joint due to heat sealing of the outer packaging material, etc. There is a need.

A large amount of gas released from the outer packaging material itself inside the vacuum insulation panel is released from the sealant layer of the outer packaging material, and there is a heat seal layer at the interface of the joint portion due to heat sealing of the outer packaging material, and vacuum insulation is also provided. The sealant layer is in contact with the space inside the panel.
Therefore, the sealant layer of the heat insulating retaining laminate of the present invention is a low gas-releasing gas-adsorbed sealant layer, which has a small amount of gas generated from itself, has excellent heat-sealing properties, and has a low gas-releasing gas-adsorbed sealant layer. By adsorbing gas containing water (steam) from the space in contact with the vacuum, the gas that penetrates the inside of the vacuum insulation panel along the interface of the joint and the gas that has penetrated the barrier base material layer are adsorbed and vacuumed. It suppresses the arrival to the inside of the heat insulating panel, and also adsorbs the gas containing water (steam) existing inside the vacuum heat insulating panel, suppresses the rise of the pressure inside the vacuum heat insulating panel, and maintains the depressurized state. Insulation can be maintained.

The outgassing property of the heat insulating retaining laminate of the present invention is dominated by the outgassing property of the low gas outgassing gas adsorption sealant layer constituting the heat insulating retaining laminate, and the low gas outgassing gas adsorption sealant layer is used. It can be known by measuring the outgassing property of the formed low outgassing gas adsorption sealant film.
For example, two strip-shaped films obtained by cutting a low gas-releasing gas adsorption sealant film into a size of 50 mm × 10 mm are placed in a test tube and heated at 90 ° C. for 60 minutes to collect air in the test tube. By gas chromatography, the concentration of the organic gas component of each carbon number in the collected air can be measured, and the amount of the organic gas component released by the low gas-releasing gas adsorption sealant film during heating can be calculated.
Among the organic gas components, in particular, the amount of the C16 gas component (organic gas component having 16 carbon atoms) was produced by using a heat insulating holding packaging material having a sealant layer formed from a low gas outgassing gas adsorption sealant film. Highly correlated with thermal conductivity in vacuum insulation panels.

The amount of the C16 gas component released when the low gas-releasing gas-adsorbed sealant film obtained by the above method is heated per unit volume of the low-gas-releasing gas-adsorbed sealant film is 10 μg / cm ³ or more, 1000 μg. It is preferably / cm ³ or less.

The gas adsorptivity of the heat-insulating holding laminate of the present invention is as follows. The change in gas concentration after being left for a day can be measured by a detector tube.

(Gas to be adsorbed)
The gas component to be adsorbed in the present invention is mainly the gas component originally contained in the heat insulating retaining laminate of the present invention (particularly the low gas outgassing gas adsorption sealant layer), heating of a heat seal, or the like. , UV, EB, or the like, which is a gas component composed of a resin decomposition product generated by decomposing the resin in the heat insulating retaining laminate, or a gas component containing water (water vapor) existing in the atmosphere.
Here, as the gas components originally contained in the heat insulating holding laminate, the gas components contained in the raw materials constituting the heat insulating holding laminate (particularly the low gas outgassing gas adsorption sealant layer) and the heat insulating. Examples thereof include gas components generated by heat history when forming a property-retaining laminate, gas components generated when heat-sealing a heat-insulating laminate, and the like.

Specific examples of the gas to be adsorbed include low molecular weight organic substances, carbon dioxide, nitrogen, oxygen, and water (water vapor).
The organic substance is a gas component derived from the heat insulating retaining laminate, and most of the compounds of the gas component have 1 to 16 carbon atoms, and the most common type is hydrocarbons, as well as alcohols and the like. Examples thereof include aldehydes, ketones and carboxylic acids.

Specific compounds of hydrocarbons include propane, propene, butane, isobutane, 2-methylbutane, butene, isobutane, 2-methylpentane, 3-ethylpentane, 2,2-dimethylpentane, 3,3-dimethylpentane. , Hexane, cyclohexane, 2-methylhexane, 3-methylhexane, 2,5-dimethylhexane, heptane, 2-methylheptane, 3-methylheptane, 3-ethylheptane, 2,2,4,6,6-pentane Examples thereof include methylheptan, 3-ethyl-3-methylheptan, 3-methylheptane, octane, 2-methyloctane, 4-ethyloctane, nonane, 3-methylnonane, decane, and dodecane.

Specific examples of the alcohols include 2-methyl-2-propanol, 2-methylpropanol, ethanol, 1-propanol and the like.

Specific examples of the aldehydes include formaldehyde, acetaldehyde, 2-methylpropanal, 3-methylbutanal and the like.

Specific examples of the ketones include acetone, MEK, MIBK, 3,3-dimethyl-2-butanone and the like.

Specific examples of the carboxylic acids include acetic acid, isovaleric acid, 2-methylpropionic acid, 2,2-dimethylpropionic acid and the like.

Specific examples of the esters include ethyl acetate, butyl acetate, and the like.

Carbon dioxide is derived from atmospheric components, aldehydes, ketones, carboxylic acids and alcohols are derived from the thermal history and atmospheric components of low gas outgassing gas adsorption sealant films or adiabatic retaining laminates, and esters are adhesive layers. Derived from.

<Gas barrier base material layer>
The gas barrier base material layer in the present invention is a base material layer having gas barrier properties, and may be composed of one layer such as a gas barrier resin film having gas barrier properties and properties as a base material, and may be a gas barrier. It may have a multi-layer structure including a layer and a base material layer.
Further, in order to improve the adhesiveness, an adhesive layer is provided between each layer constituting the gas barrier base material layer or between the other layers, and the surface of each layer is subjected to a desired surface treatment in advance, if necessary. Layers can be provided.

For example, pretreatment such as corona discharge treatment, ozone treatment, low temperature plasma treatment using oxygen gas or nitrogen gas, glow discharge treatment, oxidation treatment using chemicals, etc. is arbitrarily performed to corona treatment layer, ozone treatment, etc. A layer, a plasma treatment layer, an oxidation treatment layer and the like can be formed and provided.

Alternatively, various coating agent layers such as a primer coating agent layer, an undercoating agent layer, an anchor coating agent layer, an adhesive layer, and a vapor-deposited anchor coating agent layer may be arbitrarily formed on the surface of each layer to form a surface treatment layer. can.
The above-mentioned various coating agent layers include, for example, polyester-based resin, polyamide-based resin, polyurethane-based resin, epoxy-based resin, phenol-based resin, (meth) acrylic-based resin, polyvinyl acetate-based resin, and polyolefins such as polyethylene or polypropylene. A resin composition containing a based resin, a copolymer thereof, a modified resin, a cellulose-based resin, or the like as the main component of the vehicle can be used.
The thickness of the gas barrier base material layer is preferably 5 μm or more and 100 μm or less, and more preferably 7 μm or more and 75 μm or less. If it is less than the above range, the rigidity and / or the gas barrier property may be insufficient, and if it exceeds the above range, the rigidity may become too strong and the workability may be deteriorated.

[Base layer]
As the base material layer, a resin film, a paper material, or the like can be used, and it may be composed of one layer, or may be a multilayer structure including two or more layers having the same or different composition.

The thickness of the base material layer depends on the material, but in the case of a resin film, it is preferably 15 μm or more and 60 μm or less, more preferably 7 μm or more and 45 μm or less.
As the resin film used for the base material layer, a film made of a thermoplastic resin can be used, which has excellent chemical or physical strength and can withstand the conditions for forming a vapor-deposited film of a metal or a metal oxide. It is preferable that the thermoplastic resin can be held well without impairing the characteristics of the vapor-deposited film.

Examples of such resins include polyolefin resins such as polyethylene resins or polypropylene resins, cyclic polyolefin resins, polystyrene resins, acrylonitrile-styrene copolymers (AS resins), and acrylonitrile-butadiene-styrene copolymers. (ABS resin), poly (meth) acrylic resin, polycarbonate resin, polyethylene terephthalate, polyester resin such as polyethylene naphthalate, polyamide resin such as various nylons, polyurethane resin, acetal resin, cellulose resin, etc. Various resins can be mentioned.
In the present invention, as the resin, polyester-based resin, polyamide-based resin, and polyolefin-based resin are preferable, and polyethylene terephthalate (PET), nylon, and polypropylene (PP) are particularly preferable.

In the present invention, the thermoplastic resin used for the base material layer can be formed into a film by various film forming methods.
For example, a method of forming a film using one kind of resin and a film forming method such as an extrusion method, a cast molding method, a T-die method, a cutting method, and an inflation method, using two or more kinds of resins. Examples thereof include a method of forming a multi-layer co-extruded film, a method of mixing two or more kinds of resins before forming a film, and a method of forming a film by the above-mentioned film forming method. Further, a film stretched in a uniaxial or biaxial direction can be obtained by using a tenter method, a tubular method, or the like.

Alternatively, one type or two or more types of resin may be applied, dried and coated on another resin film, or a resin melted by a T-die method or the like may be laminated.
In the present invention, as the resin film, a biaxially stretched PET film, a biaxially stretched nylon film, a biaxially stretched PP film or a sheet is preferably used.

In addition, when the resin film is formed into a film, for example, the film's processability, heat resistance, weather resistance, mechanical properties, dimensional stability, antioxidant property, slipperiness, releasability, flame retardancy, and resistance Various plastic compounding agents and additives can be added for the purpose of improving and modifying mold properties, electrical properties, strength, etc., and the amount of addition thereof is from a very small amount to several tens of percent. It can be arbitrarily added depending on the above.
In the above, as general additives, for example, lubricants, cross-linking agents, antioxidants, ultraviolet absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments, reforming resins and the like are used. be able to.

[Gas barrier layer]
The gas barrier layer is a vacuum heat insulating panel manufactured by using the heat insulating laminated body of the present invention, and a gas containing water (water vapor) in the atmosphere permeates the heat insulating laminated body from the outside to the inside of the vacuum heat insulating panel. It is a layer that suppresses the coming.
As the gas barrier layer, one or a combination of two or more selected from the group consisting of a gas barrier resin film, a metal foil, a resin film with a metal or metal oxide vapor deposition layer, and a gas barrier resin coating film can be used.

As the gas barrier resin film, for example, a resin film made of a resin such as PET, polybutylene terephthalate, polyethylene naphthalate, polyamide, polyimide, polyvinyl alcohol, or an ethylene / vinyl alcohol copolymer is preferable.

As the metal foil, an aluminum foil having a thickness of 3 μm or more and 15 μm or less is preferable.

As the resin film with a metal or metal oxide vapor-deposited layer, it is preferable that an aluminum vapor-deposited film, a silica vapor-deposited film, and an aluminum oxide vapor-deposited film are formed on at least one surface of the above-mentioned base material resin film. As a commercially available resin film with an aluminum oxide thin-film film, for example, an alumina-deposited IB-PET-PIR (thickness) manufactured by Dainippon Printing Co., Ltd., which is a PET film in which alumina is vapor-deposited on one side by the PVD method. 12 μm), silica-deposited IB-ON-UB (thickness 15 μm), and the like.

As the gas barrier resin coating film, a coating film containing a sol-gel process hydrolyzed polycondensate formed from a metal alkoxide and a water-soluble polymer is preferable.

The metal leaf for the gas barrier layer, the resin film with the metal or metal oxide thin-film deposition layer can be adhered to other layers by using a dry laminate adhesive.
Alternatively, by using the resin film for the base material layer as the resin film of the resin film with the metal or metal oxide vapor-deposited layer, the lamination to the base material layer can be omitted.

<Low gas outgassing sealant layer>
The low gas-releasing gas-adsorbed sealant layer is a layer containing a low-gas-releasing resin having heat-sealing properties and a gas adsorbent, has heat-sealing properties, has low outgassing properties, and is water (steam). Can adsorb gas containing.
The low gas outgassing gas adsorption sealant layer may have a single-layer structure of one layer, or may have a multi-layer structure of two or more layers.
For example, it may be composed of an adsorption layer containing a low outgassing resin, a gas adsorbent and a hygroscopic agent, and a heat seal layer containing a low outgassing resin, and the two heat seal layers are adsorption layers. It may have a three-layer structure sandwiching the above.
Alternatively, the adsorption layer may be a layer composed of an adsorption layer containing an outgassing resin and a gas adsorbent and a hygroscopic layer containing a low outgassing resin and a hygroscopic agent.

The content of the low gas-releasing resin in the total low-gas-releasing gas adsorption sealant layer is preferably 70% by mass or more and 99.9% by mass or less, and more preferably 80% by mass or more and 99.9% by mass or less. If it is less than the above range, the low gas release property of the low gas outgassing sealant may be insufficient, and if it is more than the above range, it becomes difficult to balance in terms of various physical properties and workability. Although it is easy, the low outgassing property is not improved so much.

The content of the gas adsorbent is preferably 0.1% by mass or more and 30% by mass or less, and more preferably 0.5% by mass or more and 25% by mass or less in the layer containing the gas adsorbent. If it is less than the above range, the gas adsorption effect may be insufficient, and if it is more than the above range, the film forming property may be deteriorated.
Here, the layer containing the gas adsorbent refers to the entire low gas-releasing gas-adsorbed sealant layer when the low-gas-releasing gas-adsorbed sealant layer is composed of only one layer, and has low gas-releasing property. When the gas adsorption sealant layer has a multi-layer structure having an adsorption layer, a heat seal layer, etc., it refers to, for example, an adsorption layer, and when the adsorption layer is composed of an adsorption layer and a moisture absorption layer, for example, the adsorption layer is referred to. Point to.

The content of the hygroscopic agent is preferably 1% by mass or more and 50% by mass or less, and more preferably 2% by mass or more and 45% by mass or less in the layer containing the hygroscopic agent. If it is less than the above range, the hygroscopic effect may be insufficient, and if it is more than the above range, the film forming property may be deteriorated.
Here, the layer containing the hygroscopic agent refers to the entire low gas outgassing gas adsorbed sealant layer when the low gas outgassing gas adsorbed sealant layer is composed of only one layer, and refers to the entire low outgassing gas adsorbed sealant layer. When the adsorption sealant layer has a multilayer structure including an adsorption layer and a heat seal layer, it refers to, for example, an adsorption layer, and when the adsorption layer is composed of an adsorption layer and a moisture absorption layer, it refers to, for example, a moisture absorption layer. ..

When the low gas outgassing gas adsorption sealant layer has a multi-layer structure having an adsorption layer, a heat seal layer, etc., in order to improve the heat sealability and the laminate property, at least one side of the low gas outgassing gas adsorption sealant layer The outermost layer is preferably a heat seal layer.
Further, the low outgassing resin contained in the adsorption layer and the low outgassing resin contained in the heat seal layer may be the same or different.

Inside the vacuum insulation panel, the low gas outgassing sealant layer is in contact with the space inside the vacuum insulation panel and exists at the joint interface of the heat seal portion, so the thickness of the low outgassing gas adsorption sealant layer is adjusted. Therefore, the gas adsorption property and the low gas release property can be adjusted.
The thickness of the low gas-releasing gas adsorption sealant layer is preferably 25 μm or more and 150 μm or less, and more preferably 30 μm or more and 100 μm or less in order to have a good balance between heat-sealing property, gas adsorption property and low gas release property. preferable. If it is thinner than the above range, the heat sealability and / or the gas adsorption property may be insufficient, and if it is thicker than the above range, the low gas release property may be inferior.

The low gas outgassing sealant layer can further contain a small amount of slip agent, antiblocking agent, antioxidant, solvent and other additives.
The low gas outgassing sealant layer of the present invention preferably contains an antioxidant in order to suppress the generation of outgassing gas due to resin deterioration in a high temperature environment. On the contrary, it is preferable to limit the use of additives that are likely to increase outgassing at high temperatures.

[Adsorption layer]
The adsorption layer is a layer containing a gas adsorbent and a hygroscopic agent, is a layer having high outgassing property, and further contains a low outgassing resin as a binder resin in order to maintain low outgassing property. Is preferable. However, other resins and various additives such as antioxidants can be contained within a range that does not significantly impair gas adsorption and outgassing.
The low gas-releasing gas adsorption sealant layer may contain one layer or two or more layers having the same or different composition.

The thickness of the adsorption layer is preferably 5 μm or more and 80 μm or less, and more preferably 7 μm or more and 75 μm or less in order to show good gas adsorption. If it is thinner than the above range, the gas adsorption property may be insufficient, and if it is thicker than the above range, the gas adsorption property is not improved so much, and the rigidity of the low gas-releasing gas adsorption sealant layer becomes too strong. Workability may decrease.

[Gas adsorption layer]
The gas adsorption layer is a layer in which the adsorption layer contains a gas adsorbent but does not contain a hygroscopic agent.

[Hygroscopic layer]
The hygroscopic layer is a layer in which the adsorbent layer contains a hygroscopic agent but does not contain a gas adsorbent.

[Heat seal layer]
The heat-sealing layer is a layer containing a low outgassing resin, has a high heat-sealing property, and preferably does not contain a gas adsorbent because it has a high heat-sealing property.
The heat-sealing resin contained is preferably a low-gas-releasing resin in order to achieve both high heat-sealing property and low outgassing property.
However, various additives such as gas adsorbents, other resins, and antioxidants can be contained within a range that does not significantly impair the heat sealability and low gas release property.
The low gas-releasing gas adsorption sealant layer may contain one layer or two or more layers having the same or different composition.

The thickness of the heat seal layer is preferably 3 μm or more and 30 μm or less, and more preferably 5 μm or more and 25 μm or less in order to show good heat sealability. If it is thinner than the above range, the heat sealability may be insufficient, and if it is thicker than the above range, the heat sealability does not improve so much, and the rigidity of the low gas-releasing gas adsorption sealant layer becomes too weak. Workability may decrease.

[Low outgassing resin]
The low outgassing resin is a resin having a small amount of gas released, and the amount of gas released varies depending on the shape of the resin, the heat history, and the like.
By containing a low gas-releasing resin having a heat-sealing property in the low-gas-releasing gas-adsorbed sealant layer in contact with the internal space of the vacuum heat insulating panel, the low-gas-releasing gas-absorbing sealant layer is imparted with heat-sealing property and released. It is possible to reduce the amount of gas and suppress the rise in pressure inside the vacuum insulation panel.
The outgassing amount of the low outgassing resin has a high correlation with the concentration of elution total organic carbon (TOC) contained in the low outgassing resin.
TOC indicates the concentration of the total amount of organic substances (organic carbon bodies) that can be oxidized in water by the concentration of carbon content, and is used as one of the typical water quality indexes. It is standardized by organic carbon (TOC) automatic measuring instrument) and the like.

The concentration of elution total organic carbon (TOC) contained in the film made of the low outgassing resin in the present invention is preferably 1.5 ppm or more and 250 ppm or less, and preferably 5 ppm or more and 200 ppm or less. It is difficult to prepare less than the above range, and it is difficult to show a significant difference in practical effect. If it is more than the above range, the low outgassing resin may be insufficient.

Here, the reason why the concentration of the elution TOC of the low outgassing resin as a single raw material is measured not in the state of raw material pellets or the like but in the filmed state is that the low outgassing resin releases low gas. This is because when the film is formed for the purpose of forming the outgassing sealant layer, various thermal histories and the like may be given to increase the elution amount of TOC.

The concentration of the elution total organic carbon (TOC) contained in the film made of the low gas-releasing resin described above is, for example, the filling water in the pouch made of the film made of the low gas-releasing resin in the present invention. The TOC concentration of the filled water is measured by filling with distilled water and elution of the organic carbon body, and the TOC concentration of the filled water before filling is subtracted as a blank to calculate the increase in the TOC concentration. The elution TOC concentration contained in the film made of the gas-releasing resin is calculated.

The increase in the TOC concentration of the filled water is preferably 0.01 ppm or more and 1.5 ppm or less, more preferably 0.02 ppm or more and 1.45 ppm or less, and 0.025 ppm or more and 1.4 ppm or less. Is more preferable. It is difficult to prepare less than the above range, and it is difficult to show a significant difference in practical effect. If it is more than the above range, the low outgassing property of the low outgassing resin may be insufficient. From the viewpoint of achieving both cost and performance, the above range is preferable.

As more specific conditions, although it depends on the application, the temperature of the filling water at the time of filling is 40 ° C to 80 ° C, the temperature at the time of storage is 25 ° C to 50 ° C, and the storage period is several days to 4 weeks. It is preferable to measure the TOC concentration of water with a total organic carbon meter or HS-GC.

In the present invention, the elution TOC concentration contained in the resin film made of the low gas-releasing resin is the filling water in a pouch having an inner size of 15 cm × 44 cm made by using the resin film made of the low gas-releasing resin. After filling and sealing with 1000 g of distilled water at 65 ° C (distilled water for high-speed liquid chromatography, manufactured by Genuine Chemical Co., Ltd.) and storing at 35 ° C for 2 weeks, the TOC concentration of the filled water is adjusted to the total TOC-L. It is preferable to calculate the elution TOC concentration contained in the resin film made of a low gas-releasing resin by using an organic carbon meter (manufactured by Shimadzu Corporation) as a standard method.

For example, when a pouch with a pouch size of 15 cm × 44 cm × 50 μm and 1000 g of filled water are used, it is contained in a film made of a low outgassing resin due to the increased concentration of TOC in the filled water as shown below. The elution TOC concentration C is calculated.
Filled water (distilled water) weight: W1 = 1000 [g]
Density of film made of low outgassing resin: S [g / cm ³ ]
Pouch size: 15 cm x 44 cm x 50 μm thickness Pouch weight: W2 = 15 x 44 x 50 x 10 ^-4 x 2 x S = 6.6 x S [g]
Elution TOC concentration contained in a film made of low outgassing resin: C [ppm]
Increase in TOC concentration in filled water: X [ppm]
Then
Total weight of elution TOC contained in the film made of low outgassing resin = C × W2 [g]
Since this elutes in W1 [g] water,
X = C × W2 / W1 = C × 6.6 × S × 10 ^-3 [ppm]
The elution TOC concentration C contained in the film made of a low outgassing resin is calculated from the following formula.
C = X / (6.6 x S x 10 ^-3 ) [ppm]
For example, when the density S of the film made of the low outgassing resin constituting the pouch is 0.92 [g / cm ³ ] and the increase X of the TOC concentration of the filled water is 0.01 [ppm],
C = 0.01 / (6.6 × 0.92 × 10 ^-3 ) = 1.64 [ppm]
It is calculated as.

The density of the low outgassing polyethylene resin is preferably 0.915 g / cm ³ or more and 0.935 g / cm ³ or less, and more preferably 0.919 g / cm ³ or more and 0.933 g / cm ³ or less. Polyethylene resins having a density in the above range tend to reduce the amount of organic gas released.

The MFR (melt flow rate) of the low outgassing polyethylene resin is preferably 0.2 g / 10 minutes or more, 10 g / 10 minutes or less, and preferably 0.5 g / 10 minutes or more and 7 g / 10 minutes or less. As long as the MFR is within the above range, good MFR can be maintained and good film-forming property and adhesiveness can be exhibited even when mixed with other resins or gas adsorbents.

As the low outgassing resin, a polyethylene resin (low outgassing polyethylene resin) is preferable because it has excellent heat-sealing properties, is resistant to UV or EB irradiation and heating, and is not easily decomposed. ..
The low outgassing polyethylene resin originally contains a small amount of outgassing gas, is resistant to UV or EB irradiation and heating, and is difficult to be decomposed, so that the amount of outgassing can be reduced. can.

Specific examples of polyethylene types of low gas-releasing polyethylene-based resin include low-density polyethylene (LDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), and linear (linear) low-density polyethylene (LLDPE). , Ethethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, ethylene-methylmethacrylic acid copolymer, ethylene-propylene copolymer, etc. Examples include, but are not limited to, low gas-released polyethylenes and mixtures of their resins.

Among the above, one or a combination of two or more selected from the group consisting of MDPE, LDPE and LLDPE is preferable.
Further, the LLDPE is preferably one or a combination of two or more selected from the group consisting of C4-LLDPE, C6-LLDPE and C8-LLDPE, and C6-LLDPE is more preferable.

Here, C4-LLDPE is a linear low-density polyethylene composed of a copolymer of ethylene and 1-butene, and C6-LLDPE is composed of ethylene and 1-hexene and / or 4-methyl-1-pentene. It is a linear low-density polyethylene made of a copolymer of ethylene, and C8-LLDPE is a linear low-density polyethylene made of a copolymer of ethylene and 1-octene.
Each molecular structure has 4 and 6 carbon atoms derived from 1-butene, 1-hexene and / or 4-methyl-1-pentene and 1-octene in the main chain of LLDPE derived from ethylene, respectively. It has a molecular structure in which 8 or 8 side chains are present.

In order to keep the amount of release gas contained in the resin low, for example, when producing the resin, it is necessary to reduce the residual amount of unreacted raw materials, the amount of low molecular weight products and by-products, and to use a polymerization catalyst. It is effective to remove it. Specifically, it improves the purity of raw materials, precisely controls conditions such as reaction temperature and pressure, and removes unreacted raw materials, low molecular weight products, by-products, and polymerization catalysts by distillation and washing. Examples thereof include a method of preventing oxidation due to contact with oxygen in the air at a high temperature.
Another method is to limit the use of additives that are likely to increase the amount of release gas when pelletizing or filming the produced resin, and to prevent oxidation due to high temperature. Specific examples include lubricants, antioxidants, antiblocking agents, solvents, and the like.

The hydrophobic zeolite may have any outer shape such as spherical, rod-shaped, or elliptical, and may have any form such as powder, lump, or granular, but is uniform when dispersed in the resin. From the viewpoint of dispersibility, kneading characteristics, film forming property and the like, powdery form is preferable.

In the present invention, the average particle size of the hydrophobic zeolite can be appropriately selected depending on the intended use, but the average particle size is preferably 0.01 μm or more and 30 μm or less, preferably 0.1 μm. As mentioned above, 20 μm or less is more preferable. Here, the average particle size is a value measured by a dynamic light scattering method.
When the average particle size is smaller than the above range, the hydrophobic zeolite tends to aggregate and the dispersibility tends to decrease. Further, when the average particle size is larger than the above range, the film-forming property of the layer containing the hydrophobic zeolite tends to be inferior, so that it tends to be difficult to add a large amount of the hydrophobic zeolite, and the surface area is further reduced. Therefore, there is a possibility that a sufficient gas adsorption effect cannot be obtained.

[Gas adsorbent]
In the present invention, the gas adsorbent preferably contains one or a combination of two or more selected from the group consisting of hydrophobic zeolite, molecular sieve, MOF, and activated carbon.

(Hydrophobic zeolite)
In the present invention, the hydrophobic zeolite used as a gas adsorbent preferably has a SiO ₂ / Al ₂ O ₃ molar ratio of 30/1 to 10000/1, and more preferably 30/1 to 3000/1. preferable. When the molar ratio is in the above range, the balance between hydrophobicity and pore size is excellent, and good gas adsorption can be achieved.
Hydrophobic zeolite can be preferably used because the adsorption effect of gas components is maintained even when exposed to 230 ° C. or higher.

Since hydrophobic zeolite is hydrophobic, it is difficult to adsorb highly polar water molecules, etc., and conversely, it has a high affinity with low-polarity organic gas, and other low-polarity gas components, hydrophobic gas, lipophilicity. It has a high affinity with oil-based gases (including solvent-based gases) and easily adsorbs them. That is, it is excellent in the function of adsorbing a gas component having no functional group. Further, when an alkali metal such as Ca, Na, K or an alkaline earth metal is present on the zeolite surface, the zeolite surface is basic and easily adsorbs acid gas by a neutralization reaction.

(Molecular Sheave)
Molecular sieves are a type of hydrophilic zeolite that adsorb highly polar molecules in porous pores. In particular, it strongly adsorbs water molecules.
Molecular sieves are written as 3A, 4A, 5A, 13X depending on the type of zeolite as the raw material, the numbers indicate the approximate diameter of the pores (angstrom), the uppercase alphabet indicates the type of zeolite, and A is the LTA type zeolite. X represents FAU type zeolite.
3A is suitable for adsorption of acetonitrile and ethanol, 5A is suitable for adsorption of aromatic compounds and the like, and 13X is suitable for adsorption of large molecules such as long-chain tertiary amines.

(Metal-Organic Framework (MOF))
As a metal-organic framework (MOF: Metal-Organic Frameworks), a salt composed of a metal ion and an organic ligand is preferably used.
The metal-organic framework can have a porous structure having a smaller pore diameter and a larger specific surface area as compared with general activated carbon or zeolite.
Specific examples of the metal organic structure include aluminum fumarate, zircon fumarate, copper trimethylate, aluminum trimethylate, zircone trimethylate, iron trimethylate, aluminum terephthalate, zirconate terephthalate, 2-methylimidazole zinc, magnesium formate. , Benzene-1,3,5-trizinc benzoate, 2,6-naphthalene-zinc dicarboxylate, aminobenzene-1,4-aluminum dicarboxylate, 2,5-dioxide benzene-1,4-dicarbochelate Examples thereof include magnesium, 4,4-dioxide biphenyl-3,3-dicarboxylate magnesium, and one or a combination of two or more selected from these groups can be used.

The pore diameter of the metal-organic framework is preferably 0.3 nm or more and 3.0 nm, and more preferably 0.3 nm or more and 2.0 nm or less. The pore diameters are, for example, 1.1 nm and 0.6 nm for 2-methylimidazole zinc salt, 0.90 nm or 0.3 nm and 0.5 nm for copper trimesic acid, 0.8 nm and 0.5 nm for aluminum terephthalate, and fumaric acid. Aluminum is 1.1 nm and 0.5 nm, aluminum trimesate is 0.7 nm and 0.6 nm, trimesic acid dilcon is 0.46 nm, 1.15 nm and 1.8 nm, magnesium formate is 0.3 nm and 0.4 nm, Trimesate is 2.5 nm and 2.9 nm.

The specific surface area of the metal-organic framework can be expressed by the BET specific surface area or the Langmuir specific surface area, and in the case of the BET specific surface area, 400 m ² / g or more and 4000 m ² / g or less are preferable, and 900 m ² / g or more and 2100 m. ² / g or less is more preferable.
In the case of the Langmuir specific surface area, 500 m ² / g or more and 5000 m ² / g or less are preferable, and 1200 m ² / g or more and 2400 m ² / g or less are more preferable.

The BET specific surface area is, for example, 1350 m ² / g for zinc 2-methylimidazole, 1500 m ² / g for copper trimesate, 950 m ² / g for aluminum terephthalate, 1000 m ² / g for aluminum fumarate, and 1100 m ² for aluminum trimesate. There are those with / g, dilcon trimesic acid 2060 m ² / g, magnesium formate 400 m ² / g, and benzene-1,3,5-zinc tribenzoate 3600 m ² / g.
The Langmuir specific surface area is, for example, 1800 m 2 / g for 2-methylimidazole zinc, 2000 m ² / g for copper trimesate, 1500 m ² / g for aluminum terephthalate, 1200 m ² / g for aluminum fumarate, and 1500 ^{m 2 for} aluminum trimesate. / G, dilcon trimesic acid is 2390 m ² / g, magnesium formate is 500 m ² / g, and benzene-1,3,5-zinc tribenzoate is 5000 m ² / g.

The metal-organic framework can absorb a molecular size according to its pore diameter and an amount of gas according to its specific surface area. For example, 2-methylimidazole zinc salt has the ability to absorb lower hydrocarbons and carbon dioxide, copper trimesinate has the ability to absorb lower hydrocarbons (especially methane) and carbon dioxide, and aluminum terephthalate has the ability to absorb methane, steam and carbon dioxide. Aluminum fumarate and zircon trimesinate are excellent in the ability to absorb water vapor, and are excellent in the ability to absorb aluminum trimesate, lower hydrocarbons (particularly methane) and water vapor.

In the present invention, among the above-mentioned metal-organic frameworks, it is preferable to use one or a combination of two or more selected from the group consisting of 2-methylimidazole zinc salt, copper trimesate, and aluminum terephthalate.

(Activated carbon)
Activated carbon is a porous substance that contains carbon as a main component and also contains oxygen, hydrogen, calcium and the like, and has been chemically or physically treated. Since it is porous and has a large surface area for its volume, it has the property of adsorbing many substances.
Since the surface of activated carbon is non-polar, it has a low adsorption force for polar molecules, and it is easy to selectively adsorb granular organic substances smaller than the pores of activated carbon.

(Heat absorbent)
In the present invention, the hygroscopic agent preferably contains one or a combination of two or more selected from the group consisting of calcium oxide, magnesium oxide, and barium oxide.

(Improved dispersibility by masterbatch of gas adsorbent)
The gas adsorbent may be directly mixed with other constituents of the low gas-releasing gas adsorption sealant layer and melt-kneaded, but the gas adsorbent may be mixed with the thermoplastic resin at a high concentration and then melt-kneaded (melt blend). ) To prepare a master batch, which is mixed with other constituents of the low gas-releasing gas adsorption sealant layer at a ratio according to the target content and melt-kneaded. It is preferable to enhance the dispersibility of the adsorbent in the low gas-releasing gas-adsorbed sealant layer.
By adopting the master batch method, the gas adsorbent can be efficiently and uniformly dispersed in the low gas-releasing gas-adsorbed sealant layer even when a gas adsorbent that tends to aggregate is used. can.

The mass ratio of the gas adsorbent / thermoplastic resin in the masterbatch is not particularly limited, but the ratio of 3/97 or more and 50/50 or less is preferable, and the ratio of 5/95 or more and 40/60 or less is more preferable. preferable.
As a method of kneading the gas adsorbent and the thermoplastic resin, various kneading methods can be applied.
The thermoplastic resin used for the master batch is used in a type and content within a range that does not significantly adversely affect the heat sealability, film forming property, gas adsorption property, and low gas release property of the entire low gas release gas adsorption sealant layer. However, a resin having high compatibility with other resins such as a heat-sealing resin and a low-gassing resin contained in the low gas-releasing gas adsorption sealant layer and having the same degree of heat-sealing property is preferable. , These may be the same or different. For example, it may be a low outgassing resin.

Specific examples of the thermoplastic resin used in the master batch include general-purpose polyethylene, polypropylene, methylpentene polymer, polyolefin resins such as acid-modified polyolefin resins, and mixtures of these resins. The type of thermoplastic resin is not limited to the resin, and the type of thermoplastic resin can be selected according to the purpose.

The MFR (melt flow rate) of the thermoplastic resin used in the masterbatch is preferably 0.2 g / 10 minutes or more and 10 g / 10 minutes or less. With an MFR in this range, melt-kneading with a gas adsorbent is easy, the gas adsorbent is easily dispersed in the outgassing gas adsorbent sealant layer, and a film of the outgassing gas adsorbent sealant layer is formed. Sex is also easy to maintain.

[Antioxidant]
It is preferable that the heat insulating retaining laminate further contains an antioxidant in the low gas outgassing gas adsorption sealant layer.
The content of the antioxidant in the total low gas-releasing gas adsorption sealant layer is preferably 0.005% by mass or more and 0.5% by mass or less, more preferably 0.01% by mass or more and 0.4% by mass or less. If it is less than the above range, the effect of containing the antioxidant may be insufficient, and if it is more than the above range, the effect of increasing the antioxidant does not change so much, and the heat sealability deteriorates. It tends to be.
The antioxidant may be contained in the adsorption layer and / or the heat seal layer constituting the low gas outgassing gas adsorption sealant layer, and the antioxidant contained in the adsorption layer and the heat seal layer may contain the antioxidant. The contained antioxidant may be the same or different.

Specific examples of the antioxidant include a phenol-based antioxidant, a phosphorus-based antioxidant, a phenol-based / phosphorus-based mixed system, and the like, and one or a combination of two or more selected from the group consisting of these is contained. It is preferable to do so.

<Adhesive layer>
The heat insulating retaining laminate of the present invention can be laminated by providing an adhesive layer between the layers of each of the constituent layers and between the layers within each layer.
Further, before forming the adhesive layer, an anchor coat layer may be formed in advance on the surface of the layer to be adhered in order to improve the adhesiveness.

The adhesive (adhesive composition) forming the adhesive layer may be a thermosetting type, an ultraviolet curable type, an electron beam curable type, or the like, and may be in any form such as an aqueous type, a solution type, an emulsion type, and a dispersed type. Well, the properties may be any of film / sheet, powder, solid, etc., and the adhesive mechanism may be any of chemical reaction type, solvent volatilization type, thermosetting type, thermosetting type, etc. It may be in the form of.

Examples of such an adhesive include a polyvinyl acetate adhesive such as polyvinyl acetate and a vinyl acetate-ethylene copolymer, and a polyacrylic composed of a copolymer of polyacrylic acid and polystyrene, polyester, polyvinyl acetate and the like. Acid-based adhesives, cyanoacrylate-based adhesives, ethylene copolymer-based adhesives consisting of copolymers of ethylene and monomers such as vinyl acetate, ethyl acrylate, acrylic acid, and methacrylic acid, cellulose-based adhesives, and polyurethane-based adhesives. Agents, polyester adhesives, polyamide adhesives, polyimide adhesives, polyolefin adhesives, amino resin adhesives consisting of urea resin or melamine resin, phenol resin adhesives, epoxy adhesives, reactive type ( Meta) Examples thereof include an elastomer adhesive made of acrylic adhesive, chloroprene rubber, nitrile rubber, styrene-butadiene rubber, etc., a silicone adhesive, an alkali metal silicate, an inorganic adhesive made of low melting point glass, and the like.
Among the above, a polyolefin-based adhesive is preferable when forming a laminate by coextrusion and film formation by an inflation method.

In one aspect of the present invention, the adhesive layer may be any of an EC (extrusion coat) adhesive, a dry laminating adhesive, a non-solvent laminating adhesive, and the like.
When an EC adhesive is used, it is not particularly limited, but for example, first, the adhesive is heated and melted, expanded and expanded in the required width direction with a T-die or the like, extruded into a curtain shape, and then flows onto the layer to be bonded. By sandwiching it between a rubber roll and a cooled metal roll, the adhesive layer is formed, and the adhesive layer is adhered to and laminated at the same time.

In another embodiment, the adhesive layer may be formed by sand lamination. In this case, the adhesive layer can be melted by heating and any resin applicable to the extruder can be used. Specifically, the resin listed as the above-mentioned thermoplastic resin having a heat-sealing property can be preferably used.

When using an adhesive for dry laminating, an adhesive dispersed or dissolved in a solvent is applied onto one film, dried, and the other film is laminated and then laminated at 30 to 120 ° C. for several hours to several hours. By aging for days, the adhesive can be cured, adhered and laminated.

When using an adhesive for non-solvent laminating, the adhesive itself is applied onto the layer to be adhered without being dispersed or dissolved in a solvent, dried, and the films forming the other layer are laminated and then laminated. The adhesive is cured and laminated by aging at ~ 120 ° C. for several hours to several days.

The dry laminating adhesive or the non-solvent laminating adhesive can be used by coating with, for example, a roll coat, a gravure roll coat, a kiss coat, etc., and the coating amount thereof is 0.1 to 10 g / m ² (dry state). Is desirable. By setting the coating amount in the above range, good adhesiveness can be obtained.

(Anchor coat layer)
The anchor coat layer can be formed from any anchor coat agent.
Examples of the anchor coating agent include organic titanium, isocyanate (urethane), polyethyleneimine, acid-modified polyethylene, polybutadiene, polyacrylic, polyester, epoxy, polyvinyl acetate, cellulose, and others. Anchor coating agents such as, etc. can be used.

[Method of manufacturing a heat insulating laminate]
The production method shown below is an example and does not limit the present invention.
The film formation and lamination of each layer constituting the heat insulating retaining laminate are, for example, wet lamination method, dry lamination method, solventless dry lamination method, extrusion lamination method, T-die co-extrusion molding method, co-extrusion lamination method, inflation. It can be done by any method such as law or others.
The obtained heat insulating retaining laminate has a chemical function, an electrical function, a magnetic function, a mechanical function, a friction / wear / lubrication function, an optical function, a thermal function, a surface function such as biocompatibility, etc. It is also possible to perform secondary processing for the purpose of imparting.

Examples of secondary processing include embossing, painting, adhesion, printing, metallizing (plating, etc.), machining, surface treatment (antistatic treatment, corona discharge treatment, plasma treatment, photochromism treatment, physical vapor deposition, chemical vapor deposition, etc.) Coating, etc.) and the like.

Below, as an example, a gas barrier base material layer [base material layer / adhesive layer / base material layer / adhesive layer / gas barrier layer] / adhesive layer / low gas outgassing gas adsorption sealant layer [heat seal layer 1 / adsorption layer / heat A case of producing a heat insulating holding laminate (heat insulating holding packaging material) having a layer structure called a seal layer 2] will be described.

(Preparation of low gas outgassing sealant film)
An adsorption layer resin composition for an adsorption layer and a low outgassing resin for a heat seal layer are prepared and prepared, respectively, and a low gas outgassing sealant film having the following layer structure is obtained by an inflation method.
Layer structure: heat seal layer 1 / adsorption layer / heat seal layer 2

(Manufacturing of heat insulating retaining laminate)
Next, the low gas outgassing gas adsorption sealant film obtained above for the low gas outgassing sealant layer, the base film 1 and the base film 2 for the base material layer, and the aluminum foil for the gas barrier layer Are laminated in this order by dry lamination (coating amount: 3.5 g / m ² , drying temperature: 70 ° C.) via a DL adhesive for the adhesive layer to obtain a heat insulating retaining laminate having the above layer structure.

(Another method of forming and laminating a low gas outgassing sealant layer)
The low gas-releasing gas-adsorbed sealant layer may be extruded or co-extruded and laminated on another layer such as a gas barrier substrate layer by an extrusion coating method. Even in the case of the extrusion coating method, the layers may be laminated via an adhesive layer, if necessary.

≪Insulation retention packaging material≫
The heat insulating holding packaging material of the present invention is a packaging material produced from the heat insulating holding laminate of the present invention, and may be the same as the heat insulating holding laminate, and various functional layers may be used as required. , A print layer and the like can be further included.
Further, the heat insulating retaining packaging material of the present invention may be subjected to laminating processing (dry laminating or extruded laminating), bag making processing, and other post-treatment processing.
Specific examples of the heat insulating holding packaging material of the present invention include a heat insulating holding packaging material for a vacuum heat insulating panel.

≪Insulation retention packaging body≫
The heat insulating holding packaging body of the present invention is a packaging body manufactured by using the heat insulating holding packaging material of the present invention, and specific examples thereof include a vacuum heat insulating panel.
Using the above vacuum heat insulating panel, a heat insulating container having a high heat insulating effect can be produced. Examples of the heat insulating container include a refrigerator, a freezer, a low temperature container, a cooler box, a heat insulating box, a greenhouse, a heat insulating box and the like.

The details of the raw materials used in the examples are as follows.
[Low outgassing resin]
-Low outgassing resin 1: Ultozex 3520L manufactured by Prime Polymer Co., Ltd. C6-LLDPE, density 0.931 g / cm ³ , MFR 2.1 g / 10 minutes. The TOC concentration of the extracted water is 0.26 ppm, and the elution TOC concentration contained in the resin film is 42.3 ppm.
-Low outgassing resin 2: Neozex 3510F manufactured by Prime Polymer Co., Ltd. C4-LLDPE, density 0.933 g / cm ³ , MFR 1.6 g / 10 minutes. The TOC concentration of the extracted water is 0.32 ppm, and the elution TOC concentration contained in the resin film is 52.0 ppm.
-Low outgassing resin 3: Ultozex 2021L manufactured by Prime Polymer Co., Ltd. C6-LLDPE, density 0.919 g / cm ³ , MFR 2.0 g / 10 minutes. The TOC concentration of the extracted water is 0.56 ppm, and the elution TOC concentration contained in the resin film is 92.3 ppm.
-Low outgassing resin 4: Novatec LC522 manufactured by Japan Polyethylene Corporation. LDPE. Density 0.923 g / cm ³ , MFR 4 g / 10 minutes. The TOC concentration of the extracted water is 0.32 ppm, and the elution TOC concentration contained in the resin film is 52.5 ppm.

[General-purpose polyethylene]
-General-purpose polyethylene 1: Evolu SP4020 manufactured by Prime Polymer Co., Ltd. C6-LLDPE, density 0.937 g / cm ³ , MFR 1.7 g / 10 minutes. The TOC concentration of the extracted water is 2.85 ppm, and the elution TOC concentration contained in the resin film is 461 ppm.
-General-purpose polyethylene 2: Evolu SP1520 manufactured by Prime Polymer Co., Ltd. C6-LLDPE, density 0.913 g / cm ³ , MFR 2.0 g / 10 minutes. The TOC concentration of the extracted water is 3.05 ppm, and the elution TOC concentration contained in the resin film is 506 ppm.

[Gas adsorbent]
Hydrophobic Zeolite 1: Mizusawa Industrial Chemicals Co., Ltd. Hydrophobic Zeolite, Mizuka Sieves EX-122. SiO ₂ / AL _{2O 3} molar ratio = 32/1, average particle size = 2.5 to 5.5 μm.
-Hydrophobic zeolite 2: Hydrophobic zeolite manufactured by Mizusawa Industrial Chemicals Co., Ltd., Silton MT400. SiO ₂ / AL _{2O 3} molar ratio = 400/1, average particle size = 5-7 μm.
-Hydrophobic zeolite 3: Hydrophobic zeolite manufactured by Mizusawa Industrial Chemicals Co., Ltd., Silton MT-2000. SiO ₂ / AL _{2O 3} molar ratio = 2000/1, average particle size = 0.8 μm.

[Heat absorbent]
・ Moisture absorbent 1: Calcium oxide manufactured by Calfine Co., Ltd. F-1300K, average particle diameter 4.3 μm.
・ Moisture absorbent 2: Magnesium oxide manufactured by Konoshima Chemical Co., Ltd. Starmag PSF-150, average particle diameter 0.6 μm.

[Antioxidant]
-Antioxidant 1: EAG-5 manufactured by Prime Polymer Co., Ltd. Contains a total of 5% by mass of phenolic antioxidants and phosphorus-based antioxidants. MFR 4.5g / 10 minutes.

[Film for base material layer]
-Base film 1: Made by Unitika Ltd., emblem ON, thickness 25 μm.
-Base film 2: Made by Toyobo Co., Ltd., Espet T4102, 12 μm thick.
-Base film 3: IB-PET-PIR manufactured by Dai Nippon Printing Co., Ltd. Alumina vapor-deposited PET film with barrier coat resin layer. 12 μm thick.

[Metal leaf for barrier layer]
-Aluminum foil 1: Made by Toyo Aluminum Co., Ltd. 6 μm thick.

[glue]
-DL Adhesive 1: Adlock RU77T / H7 manufactured by Rock Paint Co., Ltd. Polyester adhesive.

[Preparation of masterbatch]
The masterbatch used for the low gas outgassing gas adsorption sealant layer was prepared as follows.

(Preparation of masterbatch 1)
The low outgassing resin 4 and the hydrophobic zeolite 1 were melt-blended at the following ratios to obtain Masterbatch 1 (MB1).
Low gas-releasing resin 4 60 parts by mass Hydrophobic zeolite 1 40 parts by mass

[Adjustment of masterbatch 2-7]
According to the formulation shown in Table 1, each raw material was melt-blended in the same manner as in Masterbatch 1 to obtain Masterbatch 2-7 (MB2-7).

[Preparation of adsorption layer resin composition]
The adsorption layer resin composition used for the adsorption layer was prepared as follows.

(Preparation of Adsorption Layer Resin Composition 1)
MB1 and the low outgassing resin 1 were dry-blended at the following ratios to obtain an adsorption layer resin composition 1.
MB1 4.2 parts by mass Low outgassing resin 1 95.8 parts by mass

(Preparation of Adsorption Layer Resin Compositions 2-9)
According to the formulation shown in Table 2, each raw material was dry-blended in the same manner as in the adsorption layer resin composition 1 to prepare the adsorption layer resin compositions 2 to 9.

[Preparation of hygroscopic layer resin composition]
(Preparation of Hygroscopic Layer Resin Composition 1)
MB5 and the low outgassing resin 1 were dry-blended at the following ratios to obtain a hygroscopic layer resin composition 1.
MB1 58 parts by mass Low gas-releasing resin 1 42 parts by mass (Preparation of hygroscopic layer resin compositions 2 to 8)
According to the formulation shown in Table 3, each raw material was dry-blended in the same manner as in the moisture-absorbing layer resin composition 1, to prepare moisture-absorbing layer resin compositions 2 to 8.

(Preparation of Gas Adsorption Hygroscopic Layer Resin Composition 1)
The adsorption layer resin composition 4 obtained above and the moisture-absorbing layer resin composition 3 were dry-blended with the following composition to obtain a gas adsorption moisture-absorbing layer resin composition 1.
Adsorption layer resin composition 4 50 parts by mass Moisture absorption layer resin composition 3 50 parts by mass

[Preparation of heat seal layer resin composition]
The heat-sealed layer resin composition 1 was obtained by dry-blending the following raw materials.
Low gas-releasing resin 1 99.68 parts by mass Antioxidant 1 0.32 parts by mass

<Example 1>
[Preparation of low gas outgassing sealant film]
Using the adsorption layer resin composition 1 obtained above, the moisture absorbing layer resin composition 1, and the low outgassing resin 1 by an inflation method, a low gas outgassing sealant film 1 having the following layer structure is obtained. rice field.
Using the obtained low gas outgassing sealant film 1, the film forming property, low gas releasing property, and gas adsorption performance were evaluated.
Layer structure of low outgassing gas adsorption sealant film 1: heat seal layer 1 / adsorption layer / moisture absorption layer / heat seal layer 2 = low outgassing resin 1 (10 μm thickness) / adsorption layer resin composition 1 (20 μm thickness) / Moisture absorption layer resin composition 1 (20 μm thickness) / Low outgassing resin 1 (10 μm thickness)

[Preparation of heat insulating laminate]
Next, the gas adsorption sealant film 1 and the base film 1, the base film 2 and the aluminum foil 1 obtained above are dried via a DL adhesive 1 (coating amount: 3.5 g / m ² , dried). By laminating by temperature: 70 ° C.), a heat insulating retaining laminate 1 having the following layer structure was obtained.
Structure of heat insulating retaining laminate 1: Gas barrier base material layer (base film 1 / DL adhesive 1 / base film 2 / DL adhesive 1 / aluminum foil 1) / DL adhesive 1 / low gas-releasing gas adsorption Sealant film 1
Using the obtained heat insulating holding laminate 1, heat sealing property evaluation and heat insulating property evaluation were carried out.
The evaluation results are shown in Table 5.

<Examples 2 to 13, Comparative Examples 1 to 4>
Using each of the raw materials shown in Tables 4, 6 and 8, the same operation as in Example 1 was carried out to prepare a low gas outgassing gas adsorption sealant film and a heat insulating retaining laminate, which were evaluated in the same manner. The results are shown in Tables 5, 7 and 9.

<Evaluation method>
[Film formation]
The appearance of the low gas outgassing gas adsorption sealant film was observed and evaluated sensually. The evaluation criteria are as follows.
○: Film formation is possible without wrinkles or bumps.
×: Many wrinkles and bumps occur, making film formation difficult.

[Outgassing amount]
Two films obtained by cutting a low gas-releasing gas adsorption sealant film into a size of 50 mm × 10 mm are placed in a test tube and heated at 90 ° C. for 60 minutes, air in the test tube is collected, and gas chromatography is performed. The concentration of the organic gas component having 16 carbon atoms in the collected air was measured, and the amount of the organic gas component having 16 carbon atoms released by the low gas-releasing gas adsorption sealant film per unit volume was calculated.

[Gas adsorption]
A low gas outgassing gas adsorption sealant film is cut into 10 x 10 cm, sealed in a gas sampling bag (GL Sciences, SMART BAG) with 600 cc of acetaldehyde gas adjusted to 100 ppm, and the gas concentration after being left for 2 days is detected in a detector tube. Measured by (Gastec, Acetaldehyde No. 92M).
Further, instead of acetaldehyde gas, acetic acid gas adjusted to 30 ppm and ethyl acetate gas adjusted to 400 ppm were used, and the evaluation was carried out in the same manner as acetaldehyde gas. For the detector tube for gas concentration measurement, "Gastec, Acetic Acid No. 81" was used for acetic acid gas, and "Gastec, Ethyl acetate No. 141L" was used for ethyl acetate gas.

[Heat sealability]
The heat insulating retaining laminate is cut into 10 cm × 10 cm, the low gas outgassing sealant layer surface is overlapped, and the area of 1 cm × 10 cm is described below using a heat seal tester (manufactured by Tester Sangyo Co., Ltd .: TP-701-A). The test piece was heat-sealed under the conditions, and the end portion was not heat-sealed and not adhered, and a test piece having a peeling strength in a bifurcated state was prepared.
Cut this test piece into strips with a width of 15 mm, attach each bifurcated end to a tensile tester, measure the peel strength (N / 15 mm) under the following conditions, and use the following pass / fail criteria. A pass / fail judgment was made.
Heat seal condition Temperature: 160 ℃
Pressure: 1kgf / cm ²
Time: 1 second Test conditions Test speed: 300 mm / min Load range: 50 N
Pass / Fail Criteria ○: 30N / 15mm or more, pass.
×: Less than 30N / 15mm and failed.

[Insulation maintenance]
Two heat insulating holding laminates cut into a rectangle having a width of 40 cm and a length of 50 cm are prepared, and the low gas-releasing gas adsorption sealant layers of the two heat insulating holding laminates are stacked so as to face each other. By heat-sealing a range of 2 cm to 3 cm from the end of the outer edge of the side, a bag body having one side open was obtained.
From the opening of the bag, glass wool with a width of 29 cm, a length of 30 cm, and a thickness of 3 cm (a non-binder glass wool with a grain size of 800 g / m ² ; product name: White Roll WR800, manufactured by Mag-Isover) was inserted as a core material. Later, air was sucked through the opening of the bag body.
Suction is performed using a vacuum packaging machine (MVR-1000 type, manufactured by Shitara Seisakusho), and with the inside of the bag being decompressed to 0.05 Pa, 5 cm to 6 cm from the end of the outer edge of the remaining side. The range of was heat-sealed.
A heat welder (Impulse Sealer FA-600-10W, manufactured by Fuji Impulse Co., Ltd.) was used for the heat seal.
Further, the outer edge portion of the entire outer circumference was folded and fixed with tape to prepare a simple vacuum heat insulating panel which is a test piece for evaluating heat insulation maintainability in which the core material is wrapped with a heat insulating holding laminate.
The thermal conductivity was measured by measuring the thermal conductivity in the thickness direction of the simple vacuum insulation panel.
First, the thermal conductivity was measured immediately after production (LMD ₁ ), and then the thermal conductivity was measured after storage at 100 ° C. for 1000 hours (LMD ₂ ). Then, the Δ thermal conductivity was calculated by the following formula, and the pass / fail of the heat insulation maintainability was judged by the following pass / fail judgment criteria.
Δ Thermal conductivity = LMD ₂ -LMD ₁
Pass / Fail Judgment Criteria: Δ Thermal conductivity is 7.0 mW / mK or less.
Fail: Δ Thermal conductivity is greater than 7.0 mW / mK.

[Elutable TOC concentration]
The pouch made of the resin film was filled with filled water and sealed, and after storage at 35 ° C. for 2 weeks, the TOC concentration of the filled water was measured to determine the increased concentration of the TOC concentration.
Pouch size: Inner dimensions 15 cm x 44 cm x 50 μm thick.
Filled water: Distilled water for high performance liquid chromatography manufactured by Junsei Chemical Co., Ltd. 65 ° C 1000g.
TOC concentration measuring instrument: TOC-L total organic carbon meter manufactured by Shimadzu Corporation.
Next, from the increased concentration of TOC in the packed water obtained above, the concentration of elution TOC contained in the resin film was calculated by the following formula.
C = X × W1 / W2
= X × W1 / (6.6 × S)
C: Concentration of elution TOC contained in the resin film [ppm]
X: Increased concentration of TOC in filled water [ppm]
W1: Filled water weight = 1000 [g]
W2: Pouch weight = 15 × 44 × 50 × 10 ^-4 × 2 × S = 6.6 × S [g]
S: Resin film density [g / cm ³ ]

<Summary of results>
The heat insulating holding laminates of all the examples show good film forming property, low outgassing property, and excellent adsorptivity to various gas components, and the heat insulating holding laminated body has good heat sealing property and heat insulating property maintaining effect. showed that.
However, the laminates of Comparative Examples 1 and 2 in which the content of the low gas-releasing resin is not sufficient have a large amount of gas emission, and the laminate of Comparative Example 1 containing no gas adsorbent has an adsorption effect on various gas components. It showed a low tendency. The laminates of Comparative Examples 1 to 3 showed an inferior heat insulating effect.
Further, the laminate of Comparative Example 4 in which the content of the gas adsorbent in the adsorption layer was too high had a good gas adsorption effect, but the film forming property was inferior. The heat insulating property maintaining effect could not be evaluated because the test piece could not be produced.

1 Insulation retention laminate 2 Insulation retention packaging material 3 Gas barrier base material layer 4 Low gas release gas adsorption sealant layer 5a Adsorption layer 5b Adsorption layer 5c Moisture absorption layer 5f Heat seal layer 6a Gas adsorbent 6b Adhesive layer 10 Insulation retention package (vacuum insulation panel)
11 Core material 12 Heat seal joint

Claims (16)

A heat insulating retaining laminate for a vacuum heat insulating panel that adsorbs a gas generated from the sealant layer itself and a gas from a space in contact with the sealant layer.
The gas is one or a combination of two or more selected from the group consisting of hydrocarbons, aldehydes, ketones, carboxylic acids, esters, alcohols, carbon dioxide, and water vapor.
The heat insulating retaining laminate has a gas barrier base material layer and an outgassing gas adsorption sealant layer.
The low gas-releasing gas-adsorbing sealant layer contains a low-gas-releasing resin having a heat-sealing property, a gas adsorbent, and a hygroscopic agent.
The low outgassing resin is a heat insulating retaining laminate having a density of 0.915 g / cm ³ or more and 0.935 g / cm ³ or less. The content of the low gas-releasing resin is 70% by mass or more and 99.9% by mass or less in the total low gas-releasing gas adsorption sealant layer.
The content of the gas adsorbent is 0.1% by mass or more and 30% by mass or less in the layer containing the gas adsorbent.
The content of the hygroscopic agent is 1% by mass or more and 50% by mass or less in the layer containing the hygroscopic agent.
The heat insulating retaining laminate according to claim 1. The heat insulating retaining laminate according to claim 1 or 2, wherein the low outgassing resin is a polyethylene-based resin. Any of claims 1 to 3, wherein the concentration of the elution total organic carbon (TOC) contained in the film made of the low outgassing resin is 1.5 ppm or more and 250 ppm or less. The heat insulating retaining laminate according to item 1. Any of claims 1 to 4, wherein the low outgassing resin is one or a combination of two or more selected from the group consisting of medium-density polyethylene, low-density polyethylene, and linear low-density polyethylene. The heat insulating retaining laminate according to item 1. The gas adsorbent comprises one or a combination of two or more selected from the group consisting of hydrophobic zeolites, molecular sieves, metal-organic frameworks (MOFs), and activated carbons. The heat insulating retaining laminate according to any one item. The one according to any one of claims 1 to 6, wherein the hygroscopic agent is one or a combination of two or more selected from the group consisting of calcium oxide, magnesium oxide, barium oxide, and hydrophilic zeolite. The heat insulating retaining laminate according to the above. The low gas-releasing gas adsorption sealant layer has an adsorption layer and a heat seal layer.
The adsorption layer is a layer containing the low gas-releasing resin, the gas adsorbent, and the hygroscopic agent.
The heat-sealing layer is a layer containing the low gas-releasing resin and having a heat-sealing property.
The outermost layer on at least one side of the low gas outgassing gas adsorption sealant layer is a heat seal layer.
The low outgassing resin contained in the adsorption layer and the low outgassing resin contained in the heat seal layer are the same or different from each other.
The heat insulating retaining laminate according to any one of claims 1 to 7. The heat insulating retaining laminate according to claim 8, wherein the adsorption layer is composed of a gas adsorption layer and a moisture absorption layer. The heat insulating retaining laminate according to any one of claims 1 to 9, wherein the low gas outgassing gas adsorption sealant layer further contains an antioxidant. The heat insulating property according to claim 10, wherein the content of the antioxidant is 0.005% by mass or more and 0.5% by mass or less in the total low gas outgassing gas adsorption sealant layer. Retaining laminate. The antioxidant is contained in the adsorption layer and / or the heat seal layer.
The antioxidant contained in the adsorption layer and the antioxidant contained in the heat seal layer are the same or different.
The heat insulating retaining laminate according to any one of claims 9 to 11. The heat insulating retaining laminate according to any one of claims 1 to 12, wherein the low gas-releasing gas-adsorbed sealant layer is a layer made of a low-gas-releasing gas-adsorbed sealant film. In the low gas outgassing gas adsorption sealant film, the amount of the organic gas component having 16 carbon atoms released when heated in air at 90 ° C. for 60 minutes is the amount per unit volume of the low gas outgassing gas adsorption sealant film. The heat insulating retaining laminate according to claim 13, characterized in that it is 10 μg / cm ³ or more and 1000 μg / cm ³ or less. A heat insulating holding packaging material for a vacuum heat insulating panel, which is produced by using the heat insulating holding laminate according to any one of claims 1 to 14. A vacuum insulating panel made by using the heat insulating retaining packaging material according to claim 15.

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