JP6891511B2 - Outer packaging material for vacuum heat insulating material, vacuum heat insulating material, and articles with vacuum heat insulating material - Google Patents

Description

The present invention relates to an outer packaging material for a vacuum heat insulating material capable of forming a vacuum heat insulating material capable of maintaining heat insulating performance for a long period of time in a high temperature environment or at room temperature.

In recent years, reduction of greenhouse gases has been promoted to prevent global warming, and energy saving of electric appliances, vehicles, equipment and buildings is required. Above all, from the viewpoint of reducing power consumption, the adoption of vacuum heat insulating materials for articles such as electric products, vehicles, buildings, and storages is being promoted. By providing these articles with a vacuum heat insulating material, it is possible to improve the heat insulating performance of the articles as a whole, and an energy reduction effect is expected.

In a vacuum heat insulating material, generally, the peripheral edges of two facing outer packaging materials are welded by heat to form a bag body, a core material such as a foamed resin or a fiber material is put in the bag, and the inside is evacuated to a vacuum state. It is formed by sealing and sealing the opening of the bag body. Since the inside of the vacuum heat insulating material is in a high vacuum state, heat transfer due to convection of air inside is blocked, so that high heat insulating performance can be exhibited.

As a gas barrier composite film for an outer packaging material of a vacuum heat insulating material that can be used even in a place exposed to high temperature, Patent Document 1 contains a gas barrier layer and a polypropylene film layer, and the amount of volatile gas is small. A gas barrier composite film is disclosed. Patent Document 1 discloses that the heat insulating performance is improved by controlling the amount of volatile gas (volatile component amount) contained in the vacuum heat insulating material to a low level.

Japanese Patent No. 5335149

In order to maintain the heat insulating performance for a long period of time in the vacuum heat insulating material that exhibits high heat insulating performance by creating a vacuum inside the vacuum heat insulating material and blocking the convection of gas, it is necessary to maintain a high degree of vacuum for a long period of time. Is required. Even if the inside of the vacuum heat insulating material is highly evacuated at the time of manufacturing, if the member constituting the outer packaging material for the vacuum heat insulating material contains volatile gas, the degree of vacuum inside the vacuum heat insulating material decreases with the passage of time. In particular, for the heat-welded layer arranged inside the barrier layer, the gas volatilized from the heat-welded layer stays inside the vacuum heat insulating material, which affects the change in the degree of vacuum of the vacuum heat insulating material over time. Becomes larger. Therefore, in order to obtain a vacuum heat insulating material capable of maintaining higher heat insulating performance in a high temperature environment and at room temperature for a long period of time, the outer packaging material for the vacuum heat insulating material, particularly the layer arranged inside the barrier layer. It is required to further suppress the amount of volatile gas from the heat.

The present invention has been made in view of the above problems, and provides an outer packaging material for a vacuum heat insulating material capable of forming a vacuum heat insulating material capable of maintaining heat insulating performance for a long period of time in a high temperature environment or at room temperature. Is the main purpose.

As a result of repeated studies to solve the above problems, the present inventor has found that, among polypropylene films, unstretched polypropylene containing a homopolymer (hereinafter, may be referred to as “CPP”) is more than other polypropylenes. We have found that the amount of volatile gas contained is small, and have completed the present invention.

Further, the above-mentioned features do not depend on whether or not the polypropylene film is stretched. That is, if the polypropylene polymer component (hereinafter, may be a polymer component) as the main component of the polypropylene film contains homopolymer as the main component, block copolymers, random copolymers, etc. may be used regardless of whether the film is stretched or not. It was found that the amount of volatile gas contained was smaller than that in the case of using a copolymer as a main component. The present invention is based on such knowledge. Hereinafter, polypropylene may be referred to as "PP".

That is, the present invention is an outer packaging material for a vacuum heat insulating material having a heat-welded layer, a barrier layer and a protective layer in this order, and the heat-welded layer is a non-stretched polypropylene film containing a homopolymer. Provided a characteristic outer packaging material for a vacuum heat insulating material.

According to the present invention, the amount of volatile gas contained in the member constituting the vacuum heat insulating material outer packaging material is reduced by using the CPP film containing the homopolymer as the heat welding layer of the vacuum heat insulating material outer packaging material. Therefore, it is possible to obtain an outer packaging material for a vacuum heat insulating material capable of forming a vacuum heat insulating material capable of maintaining the heat insulating performance for a long period of time in a high temperature environment or at room temperature.

In the above invention, the amount of volatile gas of the unstretched polypropylene film at 90 ° C. ^{is preferably 15 mg / m 2} or less. When the amount of volatile gas of the CPP film is within the above range, it can be used as an outer packaging material for a vacuum heat insulating material capable of forming a vacuum heat insulating material capable of maintaining heat insulating performance for a long period of time in a high temperature environment or at room temperature. Because.

The present invention is characterized in that it is an outer packaging material for a vacuum heat insulating material having a heat welding layer, a barrier layer and a protective layer in this order, and the heat welding layer is a polypropylene film containing a homopolymer as a main component. Provide an outer packaging material for a vacuum heat insulating material.

According to the present invention, since the polymer component of the PP film used as the heat welding layer contains a homopolymer as a main component, the amount of volatile gas contained in the heat welding layer can be reduced, and the amount of volatile gas is small. It can be used as an outer packaging material for vacuum heat insulating materials. Further, the outer packaging material for the vacuum heat insulating material of the present invention can suppress a decrease in the internal vacuum due to the gas volatilized from the heat-welded layer when used as the vacuum heat insulating material, and therefore, in a high temperature environment or at room temperature It is possible to form a vacuum heat insulating material that can maintain the heat insulating performance for a long period of time.

In the above invention, the amount of volatile gas of the polypropylene film at 90 ° C. ^{is preferably 15 mg / m 2} or less. When the amount of volatile gas of the PP film is within the above range, it can be an outer packaging material for a vacuum heat insulating material capable of forming a vacuum heat insulating material capable of maintaining heat insulating performance for a long period of time in a high temperature environment or at room temperature. Because.

In the above invention, the heat welding layer is, wave number of the infrared absorption spectrum, with respect to the peak intensity of the absorption peak peak intensity is maximum in the wave number region of 1380 ± 10 cm ^-1, from 700 cm ^-1 to 790 cm ^-1 The ratio of the peak intensities of the absorption peaks having the maximum peak intensities in the region is preferably 0.05 or less. The absorption peak having the maximum peak intensity in the desired wave number region may be referred to as the maximum absorption peak (in the desired wave number region).
1380cm to the maximum absorption peak derived from the propylene unit appeared in the vicinity of ^-1, units other than propylene units that appear in the wave number region of from 700 cm ^-1 to 790 cm ^-1 (hereinafter, sometimes referred to as other units.) From It is presumed that the purity of the homopolymer is high in the PP film in which the peak intensity ratio of the maximum absorption peak is equal to or less than a predetermined value. This is because the outer packaging material for the vacuum heat insulating material of the present invention can reduce the amount of volatile gas from the heat-welded layer by using such a PP film as the heat-welded layer.
The unit means a structural unit (monomer unit) of various polymers.

In the aspect described above, the heat welding layer is, in the infrared absorption spectrum, the absorption peak peak intensity is maximum and first absorption peak at a wave number region of ^{720cm -1 ± 5cm -1, 730cm -1} ± 5cm ^When the absorption peak having the maximum peak intensity in the wavenumber region of -1 is defined as the second absorption peak and the absorption peak having the maximum peak intensity in the wavenumber region of 1380 ± 10 cm ^-1 is defined as the third absorption peak, the above-mentioned first absorption peak is used. It is preferable that the ratio of the peak intensity of at least one of the first absorption peak and the second absorption peak to the peak intensity of the three absorption peaks is 0.05 or less.
Above all, the ratio of the peak intensity of the first absorption peak to the peak intensity of the third absorption peak and the ratio of the peak intensity of the second absorption peak to the peak intensity of the third absorption peak are 0, respectively. It is preferably 0.05 or less.

Random PP and block PP often contain ethylene units as other units, and ethylene units tend to have high-intensity peaks near each wave number of ^{720 cm -1} and 730 cm ^-1. .. The PP film in which the peak intensity ratio between the maximum absorption peak derived from the ethylene unit and the maximum absorption peak derived from the propylene unit appearing in the vicinity of the above two wave numbers is equal to or less than a predetermined value shall contain almost no random copolymer or block copolymer. It is presumed that the purity of the homopolymer is high. This is because the outer packaging material for the vacuum heat insulating material of the present invention can reduce the amount of volatile gas from the heat-welded layer by using such a PP film as the heat-welded layer.

The present invention is a vacuum heat insulating material having a core material and an outer packaging material for the vacuum heat insulating material that encloses the core material, and the outer packaging material for the vacuum heat insulating material has a heat welding layer, a barrier layer and a protective layer. Provided is a vacuum heat insulating material having the order in this order, wherein the heat-welded layer is a non-stretched polypropylene film containing a homopolymer.

Further, the present invention is a vacuum heat insulating material having a core material and an outer packaging material for the vacuum heat insulating material that encloses the core material, and the outer packaging material for the vacuum heat insulating material is a heat welding layer, a barrier layer and a protective layer. In this order, the heat-welded layer provides a vacuum heat insulating material characterized in that the heat-welded layer is a polypropylene film containing a homopolymer as a main component.

According to the present invention, since the outer packaging material for the vacuum heat insulating material is the outer packaging material for the vacuum heat insulating material of the present invention, the heat insulating performance can be maintained for a long period of time in a high temperature environment or at room temperature. It can be used as a material.

The present invention is an article having a heat insulating region and an article with a vacuum heat insulating material provided with the vacuum heat insulating material, and the vacuum heat insulating material includes a core material and an outer packaging material for the vacuum heat insulating material that encloses the core material. The outer packaging material for the vacuum heat insulating material has a heat-welded layer, a barrier layer and a protective layer in this order, and the heat-welded layer is a non-stretched polypropylene film containing a homopolymer. Provide articles with vacuum heat insulating material.

Further, the present invention is an article having a heat insulating region and an article with a vacuum heat insulating material provided with the vacuum heat insulating material, wherein the vacuum heat insulating material includes a core material and an outer packaging material for the vacuum heat insulating material that encloses the core material. The outer packaging material for the vacuum heat insulating material has a heat-welding layer, a barrier layer and a protective layer in this order, and the heat-welding layer is a polypropylene film containing a homopolymer as a main component. Provide an article with a vacuum heat insulating material.

According to the present invention, the vacuum heat insulating material is the vacuum heat insulating material of the present invention described above, and the heat insulating performance can be maintained for a long period of time in a high temperature environment or at room temperature. The heat from the heat source portion is insulated by the vacuum heat insulating material to prevent the temperature of the entire device from becoming high, while in the device having the heat insulating portion, the temperature state of the heat insulating portion is maintained by the vacuum heat insulating material. Can be kept. As a result, it is possible to obtain a device having high energy saving characteristics with reduced power consumption.
As described above, according to the present invention, the vacuum heat insulating material provided in the article is the vacuum heat insulating material using the outer packaging material for the vacuum heat insulating material, and maintains the heat insulating performance for a long period of time in a high temperature environment or at room temperature. Therefore, it can be an article having good heat insulating performance.

In the present invention, it is possible to provide an outer packaging material for a vacuum heat insulating material capable of forming a vacuum heat insulating material capable of maintaining the heat insulating performance for a long period of time in a high temperature environment or at room temperature.

It is the schematic sectional drawing which shows an example of the external packaging material for a vacuum heat insulating material of this invention. It is a schematic perspective view and schematic sectional view which shows an example of the vacuum heat insulating material of this invention. It is a graph which shows the result of having measured the amount of an organic component among the volatile gases contained in various CPP films. It is a graph which shows the result of having measured the amount of an inorganic component in the volatile gas contained in various CPP films. It is an infrared absorption spectrum of a polypropylene homopolymer film and a polyethylene film. It is a graph which shows the time-dependent change of the thermal conductivity of the vacuum heat insulating material measured in an Example and a comparative example. It is a graph showing the peak intensity in the infrared absorption spectrum ratio _I B / _{I A} and _I C / _{I A} of the PP film of Reference Example.

Hereinafter, the outer packaging material for the vacuum heat insulating material, the vacuum heat insulating material, and the device with the vacuum heat insulating material of the present invention will be described. In the following description, the "external packaging material for vacuum heat insulating material" may be referred to as the "external packaging material".

A. Outer packaging material for vacuum heat insulating material The outer packaging material for vacuum heat insulating material of the present invention can be divided into two modes according to the specifications of the heat-welded layer. Hereinafter, each aspect will be described.

I. The first aspect The outer packaging material for a vacuum heat insulating material of the present invention is an outer packaging material for a vacuum heat insulating material having a heat welding layer, a barrier layer and a protective layer in this order, and the heat welding layer contains a homopolymer. It is characterized by being a non-stretched polypropylene film.

The outer packaging 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 outer packaging material of the present invention. The outer packaging material 10 of the present invention has a heat welding layer 1, a barrier layer 2, and a protective layer 3 in this order. A non-stretched polypropylene film containing a homopolymer is used for the heat welding layer 1.

2 (a) is a schematic perspective view showing an example of the vacuum heat insulating material using the outer packaging material of the present invention, and FIG. 2 (b) is a sectional view taken along line XX of FIG. 2 (a). .. As illustrated in FIGS. 2A and 2B, in the vacuum heat insulating material 20, the peripheral edges of the two opposing outer packaging materials 10A and 10B are heat-welded and sealed, and the outer packaging materials 10A and 10B are sealed. The core material 11 is housed inside the space sealed by the metal, and the inside is depressurized to be in a vacuum state. The sealing portion on the periphery of the outer packaging materials 10A and 10B becomes the end portion 12 of the vacuum heat insulating material 20. Since the reference numerals in FIG. 2 indicate the same members as those in FIG. 1, the description thereof will be omitted here.

As described above, the vacuum heat insulating material is put into a vacuum state by depressurizing the inside at the time of manufacturing, and the convection of the gas inside is blocked, so that high heat insulating performance can be exhibited. However, when the member located inside the barrier layer contains volatile gas, the volatile gas stays inside the vacuum heat insulating material and is diffused, so that the degree of vacuum inside the vacuum heat insulating material is lowered and high heat insulating performance is maintained. You may not be able to do it. In the present invention, by using a CPP film containing a homopolymer as the heat welding layer of the outer packaging material, the amount of volatile gas contained in the member located inside the barrier layer can be reduced, so that the temperature is high. It can be an outer packaging material capable of forming a vacuum heat insulating material that can maintain heat insulating performance for a long period of time in an environment or at room temperature.

The outer packaging material of the present invention has a heat welding layer, a barrier layer, and a protective layer in this order. Hereinafter, each configuration of the outer packaging material of the present invention will be described.

1. 1. Heat-welded layer The heat-welded layer in the present invention is a portion that comes into contact with the core material when the vacuum heat insulating material is formed using the outer packaging material, and is a heat-welded surface that heat-welds the ends of the opposing outer packaging materials. It is the part to be formed. In the present invention, a non-stretched polypropylene film containing a homopolymer is used as such a heat-welded layer.

Since polypropylene has higher heat resistance than polyethylene used as the heat welding layer in the outer packaging material of the conventional vacuum heat insulating material, it can also be used in the vacuum heat insulating material used in a place exposed to high temperature. Such polypropylene includes unstretched polypropylene (CPP) which is not stretched in the manufacturing process and stretched polypropylene (OPP) whose orientation crystallinity is enhanced by stretching in the manufacturing process. Among them, CPP is excellent in heat-sealing property, and therefore can be suitably used as a heat-welding layer of an outer packaging material.

However, some polypropylenes contain a large amount of volatile gas. When such a polypropylene film is used as the heat-welding layer, the gas volatilized from the heat-welding layer is diffused inside the vacuum heat insulating material, so that the degree of vacuum inside the vacuum heat insulating material decreases with time, and the vacuum heat insulating material becomes It may not be possible to maintain the heat insulating performance for a long period of time. As a result of repeated studies by the present inventor to solve such a problem, among polypropylenes, unstretched polypropylene (CPP) containing a homopolymer contains a smaller amount of volatile gas than other polypropylenes. The present invention has been completed.

Polypropylene, which is a raw material for polypropylene films, includes homopolymers produced by using a single monomer and copolymers produced by using two or more kinds of monomers. The above copolymers can be further classified according to the sequence of monomers, such as random copolymers having an unordered sequence of monomers and block copolymers having a long continuous sequence of monomers of the same type. As a result of repeated studies on the amount of volatile gas contained in these various polymers, the present inventor has found that homopolymers contain less volatile gas content than copolymers such as random copolymers and block copolymers. It was.

FIG. 3 is a graph showing the results of measuring the amount of organic components in the volatile gas contained in each CPP film containing the block copolymer, the random copolymer, and the homopolymer. The amount of the organic component is the total of hydrocarbons such as 2-methyl-1-pentene and methylcyclopentane, and an antioxidant (τ-butylphenol), and the amount of the organic component of each film is measured as follows. It was quantified by the method and analytical conditions. Measurements and analyzes were performed on three samples for each CPP film. For each CPP film, the three bands on the left side of the graph show the quantitative results of each sample, and the rightmost band and numerical values show the average for the three samples.

The CPP film containing the block copolymer, the random copolymer, and the homopolymer used for measuring the amount of the organic component shown in FIG. 3 is a film composed of each polymer, that is, a non-stretched polypropylene block copolymer. Each CPP film is a film, a non-stretched polypropylene random copolymer film, and a non-stretched polypropylene homopolymer film.

<Measurement method>
For each CPP film, two test pieces cut into a size of 1 cm × 5 cm were placed in a sample tube, and the sample tube was analyzed by a purge & trap GC / MS method under the following conditions. For the quantification, a calibration curve prepared according to the C16 standard was used, and the total amount of organic gas volatilized from the film was calculated as a ^{C16 conversion value (mg / 10 cm 2).}

<Purge & trap conditions>
-Device name: JTD505 manufactured by Nippon Analytical Industry Co., Ltd.
・ Heating temperature: 90 ° C
・ Cooling temperature: -60 ℃
・ Adsorbent: Glass wool ・ Purge time: 60min
・ Total split ratio (introduction amount: displacement) = 1:10
-Column flow rate: 1 ml / min

<GC / MS conditions>
-Device name: Agilent 6890/5973
・ Capillary column ・ Name: DB-5MS equivalent ・ Fixed phase: 5% diphenyl dimethyl polysiloxane (slight polarity)
-Length x film thickness x inner diameter: 30 m x 0.25 μm x 0.25 mm
-Column flow rate: 1 ml / min
-Oven conditions: 50 ° C (5 min) → (10 ° C / min) → 320 ° C (3 min)

Further, FIG. 4 is a graph showing the results of quantifying the amount of the inorganic component in the volatile gas contained in each CPP film containing the same block copolymer, random copolymer, and homopolymer as in FIG. 3. The amount of the inorganic component is the total of each amount of hydrogen, water, nitrogen, carbon monoxide, oxygen, and carbon dioxide, and the quantification of the inorganic component of each CPP film is quantified by the following measuring method and analytical conditions. It was done.

For each CPP film, a test piece cut out to a size of 4 mm × 4 mm was analyzed by heating under the following conditions by TDS (heated desorption gas analysis) measurement.
<Heating conditions>
-Device name: EMD-WA1000S manufactured by Electronic Science
-Heating conditions: 30 ° C to 90 ° C
・ Temperature rise rate: 10 ° C / min
・ Holding temperature: 90 ° C
・ Heat the sample on the SiC stage

<Measurement method>
・ MID method (quantitative)
-Measured mass number (M / Z): 2 (H ₂ ), 18 (H ₂ O), 28 (N ₂ · CO), 32 (O ₂ ), 44 (CO ₂ )

From FIG. 3 described above, it can be seen that the amount of the organic component of the homopolymer is significantly smaller than that of the block copolymer. On the other hand, from FIG. 4, it can be seen that the amount of the inorganic component of the homopolymer is significantly smaller than that of the random copolymer. Therefore, it can be seen that homopolymers are significantly less than copolymers such as block copolymers and random polymers in terms of the amount of volatile gas, which is the sum of the amount of organic components and the amount of inorganic components.

In general, copolymers are polymerized with components other than polypropylene, such as rubber components, depending on the desired properties, whereas homopolymers contain almost no components other than propylene. Compared to copolymers, homopolymers have a smaller amount of volatile gas because the amount of volatile gas contained in polypropylene is extremely small due to the propylene component, and most of the volatile gas is derived from components other than polypropylene. It is presumed that it is because of it.

In the present invention, the amount of volatile gas of the CPP film used for the heat welding layer at 90 ° C. is preferably 15 mg / m ² or less, particularly 10 mg / m ² or less, and particularly preferably 5 mg / m ² or less. When the amount of volatile gas of the CPP film is within the above range, the outer packaging material of the present invention can be made into a vacuum heat insulating material capable of maintaining the heat insulating performance for a long period of time in a high temperature environment or at room temperature. Because it can be done.
The amount of volatile gas at 90 ° C. of the CPP film can be at least the amount of the organic component quantified by the above method, and the total amount of the organic component and the inorganic component is preferably within the above range. ..

In the present invention, the "non-stretched polypropylene film containing a homopolymer" is a sheet of CPP containing a homopolymer. Further, in the present invention, "CPP containing a homopolymer" is a CPP containing a homopolymer as a main component, and "having a homopolymer as a main component" means that the content of a component other than propylene contained is 10. It means that it is within the range of% by weight or less, particularly 5% by weight or less, particularly 1% by weight or less. Examples of the above-mentioned "components other than propylene" include anti-blocking agents, lubricants, flame retardants, organic fillers and the like. Further, the above-mentioned "components other than propylene" here include, in addition to the above-mentioned additives, polymers other than PP homopolymers such as PP copolymers, and other monomers.

Further, in the present invention, the polymer component that is the main component of the CPP film preferably contains a homopolymer of PP as a main component. The fact that the polymer component contains a homopolymer of PP as a main component means that the content of units other than the propylene unit contained in the polymer component is small, and preferably the polymer component does not contain units other than the propylene unit. .. Specifically, when the total polymer component of the PP film is 100% by mass, the content of units other than the propylene unit is preferably 1.0% by mass or less, and more preferably 0.5% by mass or less. It is preferable, and it is particularly preferable that it is 0.3% by mass or less.
Units other than the propylene unit (that is, other units) are, for example, units other than the propylene unit among the units constituting the random copolymer of PP, and units constituting the copolymer coexisting with the homopolymer in the block copolymer of PP. Among them, units other than the propylene unit and the like can be mentioned. The other unit has a monomer skeleton that polymerizes with a propylene monomer in a random copolymer of PP, and a monomer skeleton that constitutes a copolymer coexisting with a homopolymer in a block copolymer of PP. Specific examples thereof include olefin units such as ethylene units and butene units in random copolymers and block copolymers. When an unreacted monomer is contained alone in the polymer component, the unit other than the propylene unit shall also contain the above-mentioned monomer other than the propylene monomer.

A homopolymer of PP (hereinafter, may be referred to as homoPP) is usually a homopolymer of a propylene monomer, whereas a random copolymer of PP (hereinafter, may be referred to as random PP) is a homopolymer of PP. It is a copolymer of propylene and a copolymerization monomer other than propylene such as ethylene, and has a structure in which a propylene unit and a unit other than the above propylene unit are randomly distributed in a polymer chain. Specifically, the ethylene propylene copolymer (EPM) in which the copolymerization monomer other than propylene is ethylene has a structure in which propylene units and ethylene units are randomly distributed in a polymer chain. Further, a block copolymer of PP (hereinafter, may be referred to as block PP) is, for example, a mixture in which a polyethylene component and an ethylene propylene rubber (EPR) component are dispersed in a homo-PP, and has a matrix portion containing a propylene unit. It has a matrix-domain structure consisting of a domain moiety containing ethylene units.

That is, when the PP film contains a homopolymer and a copolymer as a polymer component, the propylene unit and other units are present in the polymer component. At this time, as the proportion of the copolymer in the polymer component increases, the content of the other units increases, so that the content of the propylene unit becomes relatively small. On the other hand, the higher the proportion of homopolymer in the polymer component, the lower the content of the other units. Therefore, if the content of the other units in the polymer component is not more than a predetermined value, the polymer component of the PP film can contain homopolymer as a main component. These features do not depend on the presence or absence of stretching of the PP film.

The content of other units in the polymer component is determined by measuring the infrared absorption spectrum of the PP film by, for example, the method described later, and determining the peak intensity of the absorption peak derived from the propylene unit and the absorption peak derived from the other unit. It can be calculated by drawing a calibration curve from the ratio. Further, as another calculation method, the PP film can be dissolved in an appropriate deuterated solvent, ¹ H-NMR can be measured, and the calculation can be performed from the integrated value.

In the PP film, the mixing ratio of the homopolymer and the copolymer in the polymer component is at least one of the absorption peak derived from the propylene unit in the infrared absorption spectrum and one or more absorption peaks derived from other units contained in the copolymer. It can be confirmed from the peak intensity ratio of one absorption peak. As described above, the copolymer contains other units such as ethylene units in addition to the propylene units. Therefore, when the PP film contains a homopolymer and a copolymer, in the infrared absorption spectrum of the PP film, in addition to the absorption peak derived from the propylene unit, the absorption peak derived from the other unit of the copolymer appears, and the absorption peak derived from the other unit described above appears. The higher the peak intensity of the absorption peak of, the higher the proportion of the copolymer in the polymer component.

Here, the absorption peak derived from the propylene unit can be the maximum absorption peak A that appears in the vicinity of ^{1380 cm -1 as shown in FIG.} The absorption peak A appearing near the wave number is presumed to be a peak derived from the CH symmetric angular vibration, and indicates the presence of the _{chain measurement methyl (-CH 3) group contained in the propylene unit.}
Further, the peak derived from the other units included in the copolymer may be at least one or more absorption peaks appearing in the frequency domain from 700 cm ^-1 to 790 cm ^-1. For example, when the polymer contains an ethylene unit, as shown in FIG. 5, high-intensity absorption peaks B and C appear in the vicinity of each wave number of ^{720 cm -1} and 730 cm ^{-1 respectively.} The absorption peaks B and C appearing in the vicinity of the wave number are presumed to be peaks derived from the ethylene unit caused by the CC skeleton vibration of the ethylene unit. The appearance of the peak in the PP film suggests the presence of ethylene units in the random PP or block PP. Depending on the type of other units such as the ethylene unit, a plurality of peaks may appear in the wavenumber region.

FIG. 5 is an infrared absorption spectrum of a polypropylene homopolymer film (hereinafter referred to as homoPP film) and a polyethylene (hereinafter referred to as PE) film. The homo-PP film is the same as the CPP film used in Example 1 described later. The PE film is the same as the PE film used in the reference evaluation described later. The infrared absorption spectrum of each film was measured by the same method as the method for measuring the infrared absorption spectrum of the heat-welded layer described later.

Therefore, the smaller the peak intensity ratio of the absorption peaks derived from other units contained in the copolymer, which appears in the above-mentioned predetermined wave number region, to the peak intensity of the maximum absorption peak appearing near ^{1380 cm -1} derived from the propylene unit, the more. Since the proportion of the other units in the polymer component is small, a PP film having a low copolymer content and a high homopolymer purity can be obtained. The above features do not depend on the presence or absence of stretching of the PP film.
The peak intensity can be the height of the absorption peak, and the peak intensity ratio can be the peak height ratio. Further, the vicinity of 1380 cm ^-1, means a tolerance relative to the 1380 cm ^-1, it can be a wave number region of 1380cm ^-1 ± 10cm ^-1. Above all, it is preferable to set the wave number region to ^{1380 cm -1} ± 5 cm ^-1.

In the present invention, with respect to the peak intensity of the absorption peak peak intensity is maximum around 1380 cm ^-1, the ratio of the peak intensity of the absorption peak peak intensity is maximum in the wave number region of from 700 cm ^-1 to 790 cm ^-1 , 0.05 or less, and more preferably 0.04 or less, particularly 0.03 or less. PP films in which the peak intensity ratio of the maximum absorption peaks derived from other units to the maximum absorption peaks derived from the propylene unit is less than or equal to a predetermined value can be made to contain almost no random copolymers and block copolymers, and are homopolymers. It is presumed that the purity is high. This is because the amount of volatile gas from the heat-welded layer can be reduced by using such a PP film as the heat-welded layer.

Relative to the peak intensity of the absorption peak peak intensity is maximum around Of these 1380 cm ^-1, the ratio of the peak intensity of the absorption peak peak intensity is maximum around 725 cm ^-1 is preferably 0.05 or less Above all, it is preferably 0.04 or less, particularly 0.03 or less.
Here, the vicinity of 725 cm ^-1, means a tolerance relative to the 725 cm ^-1, it can be a wave number region of 725cm ^-1 ± 25cm ^-1. The permissible range may be ± 20 cm ^-1 , ± 15 cm ^-1 , or ± 10 cm ^-1 .

When the random PP or block PP mainly contains an ethylene unit as another unit, a strong absorption peak derived from the ethylene unit tends to appear in the vicinity of ^{725 cm-1.} Therefore, by defining the peak intensity ratio of the maximum absorption peak in the vicinity of the maximum absorption peak and 1380 cm ^-1 in the vicinity of 725 cm ^-1, it can be pure homopolymer with high PP film.

In the above-wave band region, when two or more absorption peak appears, in the infrared absorption spectrum, the absorption peak and the peak intensity peak intensity is maximum in the wave number region of from 700 cm ^-1 to 790 cm ^-1 The second largest absorption peak (sometimes referred to as the second maximum absorption peak) is defined as the first absorption peak and the second absorption peak from the low wavenumber side, and the absorption peak having the maximum peak intensity near ^{1380 cm -1 is defined as the absorption peak.} When the third absorption peak is used, the ratio of the peak intensity of at least one of the first absorption peak and the second absorption peak to the peak intensity of the third absorption peak is 0.05 or less. It is preferable, and above all, it is preferably 0.04 or less, particularly 0.03 or less.

Among them ^{, the absorption peak having the maximum peak intensity near 725 cm -1} and the absorption peak having the second highest peak intensity are defined as the first absorption peak and the second absorption peak from the low wavenumber side, and the peak intensity is around ^{1380 cm -1.} When the maximum absorption peak is defined as the third absorption peak, the ratio of the peak intensity of at least one of the first absorption peak and the second absorption peak to the peak intensity of the third absorption peak is 0. It is preferably 05 or less, and more preferably 0.04 or less, particularly 0.03 or less.

The ratio of the peak intensity of the first absorption peak to the peak intensity of the third absorption peak is defined as the first peak intensity ratio. Further, the ratio of the peak intensity of the second absorption peak to the peak intensity of the third absorption peak is defined as the second peak intensity ratio.

In the wave number region of from the 700 cm ^-1 to 790 cm ^-1, if a large peak intensity derived from the other units contained in the copolymer appears more, the maximum absorption peak and a second largest absorption peak at the wave number region This is because at least one of them exhibits a predetermined peak intensity ratio to the maximum absorption peak derived from the propylene unit, so that the purity of the homopolymer of the PP film is increased.

In the wave frequency region, at least one of the first peak intensity ratio and the second peak intensity ratio may be within the range of the above-mentioned peak intensity ratio, and among them, the first peak intensity ratio and the second peak intensity ratio are respectively. It is preferably within the range of the peak intensity ratio described above.

Further, in the heat-welded layer, in the infrared absorption spectrum, the ^{absorption peak having the maximum peak intensity near 720 cm -1} is set as the first absorption peak, and the absorption peak having the maximum peak intensity near ^{730 cm -1 is set as the second absorption peak.} When the absorption peak is defined as ^{the absorption peak and the absorption peak having the maximum peak intensity near 1380 cm -1 is} defined as the third absorption peak, the first absorption peak and the second absorption peak have the same as the peak intensity of the third absorption peak. The ratio of at least one of the peak intensities is preferably 0.05 or less, and more preferably 0.04 or less, particularly 0.03 or less.
At least one of the first peak intensity ratio and the second peak intensity ratio may be within the range of the above-mentioned peak intensity ratio, and among them, the first peak intensity ratio and the second peak intensity ratio are each. , It is preferable that it is within the range of the peak intensity ratio described above.

Here, the vicinity of 720 cm ^-1, can be a wave number region of 720 cm ^-1 ± ^{5 cm -1,} it is preferably a wave number region of inter alia 720cm ^-1 ± ^{2cm -1.} Further, the vicinity of 730 cm ^-1, can be a wave number region of 730 cm ^-1 ± ^{5 cm -1,} it is preferably a wave number region of inter alia 730cm ^-1 ± ^{2cm -1.}

Random PP and block PP often contain ethylene units as other units, and ethylene units often have high-intensity peaks ^{mainly around 720 cm -1} and 730 cm ^-1. PP films in which at least one of the first absorption peak and the second absorption peak derived from the ethylene unit of the copolymer has a peak intensity of a predetermined value or less with respect to the peak intensity of the third absorption peak derived from the propylene unit are a random copolymer and a block. It can be made to contain almost no copolymer, and it is presumed that the purity of the homopolymer is high. That is, since such a PP film can contain homo-PP as a main component among the polymer components, the amount of volatile gas generated can be reduced by using it as the heat welding layer.

The infrared absorption spectrum in the present invention can be measured by a single reflection ATR measurement method using a Fourier transform infrared spectrophotometer (FT-IR), and the horizontal axis is the wave number and the vertical axis is the absorbance. Specifically, the measuring method is as follows: an accessory device is installed in the spectroscope, and an outer packaging material cut out to a desired size (several cm square) is set so that the surface on the heat welding layer side faces the accessory device. By measuring the spectrum of one-time reflection when the surface of the heat-welded layer is irradiated with infrared rays, the infrared absorption spectrum of the heat-welded layer can be obtained. By adjusting the penetration depth of light according to the thickness of the heat-welded layer at the time of measurement, it is possible to measure the infrared absorption spectrum of the heat-welded layer in the state of the outer packaging material.
(Measurement condition)
-Spectroscope: Fourier transform infrared spectrophotometer FTS-7000 (manufactured by Digilab)
-Attachment: Attachment for single reflection ATR: Silver Gate Evolution (manufactured by SPECAC)
Prism: Ge crystals incident angle: 45 ° incident Measurement wavenumber ^region: 700cm ^{-1 ~4000cm} -1
・ Resolution: 4 cm ^-1
・ Scan speed: 20kHz
・ Cumulative number: 64 times

The thickness of the CPP film used as the heat welding layer in the present invention is preferably in the range of, for example, 20 μm to 100 μm, particularly preferably in the range of 25 μm to 90 μm, and particularly preferably in the range of 30 μm to 80 μm. If the thickness of the heat-welded layer is larger than the above range, the probability of outside air entering from the heat-welded portion increases, and if the thickness is smaller than the above range, the desired adhesive force may not be obtained.

As the CPP film as described above, a commercially available product may be used, or a CPP obtained by polymerizing propylene by a known method and molded into a sheet may be used.

2. Barrier layer The barrier layer in the present invention is usually a site formed between the heat welding layer and the protective layer. Such a barrier layer is generally used as a barrier layer, for example, a metal foil, a resin base material, and a laminate having a barrier film containing an inorganic substance arranged on at least one surface side of the resin base material. Can also be used. This is because by using such a barrier layer, it is possible to obtain an outer packaging material capable of forming a vacuum heat insulating material that can maintain the heat insulating performance for a long period of time in a high temperature environment or at room temperature.

Examples of the metal foil include metal foils such as aluminum, nickel, stainless steel, iron, copper, and titanium.

Examples of the laminated body include known barrier films and the like. Examples of the inorganic substance constituting the barrier film of the laminate include metals, inorganic compounds such as metal oxides and inorganic oxides such as silicon oxide. The barrier film may be a coating film or a vapor-deposited film, but a vapor-deposited film is preferable. This is because the adhesion to the resin base material is high and high gas barrier performance can be exhibited.
The resin base material of the laminate is not particularly limited, and for example, a resin base material in a known barrier film such as a PET film can be used.

The barrier layer may be one in which a barrier composition film containing a barrier composition is further arranged on the barrier film of the laminated body. Examples of the barrier composition include a barrier composition containing at least one of a polyvinyl alcohol-based resin and an ethylene vinyl alcohol copolymer.

The barrier layer may be a single layer, or may be a multilayer body in which layers made of the same material or layers made of different materials are laminated. When the barrier layer is a laminate having the above-mentioned resin base material and the barrier membrane, the barrier membrane may be a single layer, or two or more barrier membranes having the same composition or barrier membranes having different compositions are laminated. May be. Further, the barrier layer may be subjected to a surface treatment such as a corona discharge treatment from the viewpoint of improving the barrier performance and the adhesion with other layers.

The thickness of the barrier layer is preferably in the range of, for example, 2 μm to 50 μm, particularly preferably in the range of 5 μm to 25 μm. If the thickness of the barrier layer is smaller than the above range, pinholes and the like are likely to occur in the barrier layer, and if the thickness of the barrier layer is larger than the above range, cracks and the like are likely to occur at the bent portion, and the heat insulating performance. May decrease. Further, when a barrier layer of a metal foil such as an aluminum foil is applied, heat bridging is likely to occur, and the heat insulating performance may be deteriorated.

The barrier performance of the barrier layer, the oxygen permeability is preferably ^{0.5cc / (m 2 · day ·} atm) or less, it is inter alia ^{0.1cc / (m 2 · day ·} atm) or less preferable. Further, the water vapor transmission rate is ^{preferably 0.5 g / (m 2} · day) or less, and more preferably 0.1 g / (m ² · day) or less. When the oxygen and water vapor transmission rates of the barrier layer are within the above ranges, it is possible to make it difficult for water, gas, etc. that have permeated from the outside to permeate into the core material inside. It is preferable that the oxygen permeability and the water vapor transmission rate of the entire outer packaging material of the present invention are also within the above ranges.

For the measurement of oxygen permeability, refer to JIS K7126-2A: 2006 (Plastic-Film and Sheet-Gas Permeability Test Method-Part 2: Isopressure Method, Annex A: Oxygen Gas Permeability Test Method by Electrolytic Sensor Method). According to this, the measurement can be performed using an oxygen gas permeability measuring device under the conditions of a temperature of 23 ° C. and a humidity of 60% RH. As the oxygen gas permeability measuring device, for example, OXTRAN manufactured by MOCON of the United States can be used. In the measurement, the surface of the outer packaging material, which is located on the barrier layer side with respect to the film that can be heat-welded in the thickness direction of the outer packaging material, is mounted in the apparatus so as to be in contact with oxygen gas, and the permeation area is measured. Perform under the condition of 50 cm ^2. The above measurement is performed according to the following procedure. First, the carrier gas is supplied into the apparatus at a flow rate of 10 cc / min for 60 minutes or more to purge. As the carrier gas, a nitrogen gas containing about 5% hydrogen can be used. After purging, the test gas is flowed into the apparatus, and after securing 12 hours as the time from the start of flowing to the equilibrium state, the measurement is started under the above temperature and humidity conditions. The test gas uses at least 99.5% dry oxygen. Under one condition, at least three samples are measured, and the average of those measurements is taken as the oxygen permeability value of the condition. The oxygen permeability described herein can be measured using a method similar to the method described above.

The water vapor transmission rate can be measured using a water vapor transmission rate measuring device under the conditions of a temperature of 40 ° C. and a humidity of 90% RH in accordance with ISO-15106-5: 2015 (differential pressure method). As the water vapor transmission rate measuring device, for example, DELTAPERM manufactured by Technolux of the United Kingdom can be used. The measurement is performed by setting the surface of the outer packaging material, which is located on the barrier layer side with respect to the film that can be heat-welded in the thickness direction of the outer packaging material, to be on the high humidity side (steam supply side). It is installed between the upper and lower chambers and has a transmission area of 64 cm ^{2 under} the above temperature and humidity conditions. For the water vapor transmission rate, at least three samples can be measured for the outer packaging material under one condition, and the average of those measured values can be used as the value of the water vapor transmission rate under that condition.

3. 3. Protective layer The protective layer is a portion that becomes the outermost layer (outermost layer) in the outer packaging material of the present invention. The protective layer has sufficient strength to protect the inside of the vacuum heat insulating material when the vacuum heat insulating material is formed using the outer packaging material of the present invention, and has heat resistance, moisture resistance, and pinhole resistance. , It is preferable that the material has excellent piercing resistance and the like.

The protective layer may be a resin having a melting point higher than that of the heat welding layer, and may be a resin sheet or a uniaxially stretched or biaxially stretched film. Examples of such a protective layer include nylon resins, polyethylene terephthalates, polyester resins such as polyethylene naphthalate, polyamide resins, polyolefin resins such as polypropylene, acrylic resins, cellulose resins, ethylene vinyl alcohol copolymers, and the like. Examples include sheets or films.

The protective layer may be a single layer, or may be a multi-layered structure in which layers made of the same material or layers made of different materials are laminated. Further, the protective layer may be subjected to surface treatment such as 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 welding layer and the barrier layer, but is generally in the range of 5 μm to 80 μm.

4. Outer packaging material for vacuum heat insulating material In the outer packaging material of the present invention, the layers constituting the outer packaging material may be laminated in direct contact with each other, or may be laminated via an interlayer adhesive. As the interlayer adhesive, an adhesive generally used for an outer packaging material for a vacuum heat insulating material can be used.

The outer packaging material may have a plurality of protective layers or barrier layers. The outer packaging material may be provided with, for example, two or more barrier layers between the heat welding layer and the protective layer, such as the first protective layer and the second protective layer on the heat welding 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. Further, the outer packaging material may have an arbitrary layer such as an anchor coat layer and a pinhole resistant layer.

The outer packaging material of the present invention may or may not have transparency, and can be appropriately set according to the use of the vacuum heat insulating material in which the outer packaging material is used. The transparency of the outer packaging material is not specified by a strict transmittance, and can be appropriately determined according to the application and the like. 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 the vacuum heat insulating material. Therefore, by putting a detection agent inside the vacuum heat insulating material, the inside is changed from the change of the detection agent. It becomes possible to visually confirm the vacuum state of.

The method for laminating the outer packaging material is not particularly limited, and any method may be used as long as each layer can be laminated so that one outermost layer has a protective layer and the other outermost layer has a heat welding layer. A known method can be used. As the laminating method, a dry lamination method in which each layer formed in advance is bonded using the above-mentioned interlayer adhesive, or a heat-melted material of each layer is extruded and bonded using a T-die or the like. Examples thereof include a method of adhering a heat-welded layer to the laminated body via an interlayer adhesive.

II. The second aspect of the outer packaging material for a vacuum heat insulating material of the present invention is an outer packaging material for a vacuum heat insulating material having a heat welding layer, a barrier layer and a protective layer in this order, and the heat welding layer is homozygous. It is characterized by being a polypropylene film (PP film) containing a polymer as a main component.

In the outer packaging material for the vacuum heat insulating material of this embodiment, in FIG. 1, the heat welding layer 1 is a PP film containing a homopolymer as a main component.

The features and effects of the PP film described in the section "1. First aspect" described above do not depend on the presence or absence of stretching of the PP film. That is, if the polymer component that is the main component of the PP film contains homopolymer as the main component, the effect of the present invention can be exhibited regardless of whether or not the film is stretched.
That is, according to this aspect, since the polymer component of the PP film used as the heat welding layer contains homopolymer as the main component, the amount of volatile gas contained in the heat welding layer can be reduced, and the amount of volatile gas can be reduced. It can be used as an outer packaging material for vacuum heat insulating materials with a small amount of material. Further, when the outer packaging material for the vacuum heat insulating material of this embodiment is used as the vacuum heat insulating material, it is possible to suppress a decrease in the internal vacuum degree due to the gas volatilized from the heat-welded layer, so that it can be used in a high temperature environment or at room temperature. It is possible to form a vacuum heat insulating material that can maintain the heat insulating performance for a long period of time.

Hereinafter, each configuration of the outer packaging material of this embodiment will be described. Since the contents other than the heat welding layer of the outer packaging material of this embodiment are the same as those described in the section of "I. 1st embodiment", the description thereof is omitted here.

1. 1. Heat-welded layer The heat-welded layer in this embodiment is a PP film containing a homopolymer as a main component.
As described in the above section "I. First aspect 1. Heat welding layer", the amount of volatile gas of polypropylene differs depending on the polymer type of polypropylene, and the larger the amount of homopolymer, the smaller the amount of volatile gas. Can be done. That is, it is estimated that the amount of volatile gas in the polypropylene film depends on the polymer species of polypropylene contained in the polymer component of the film, and does not depend on the presence or absence of stretching of the film.
In this embodiment, by using a PP film containing a homopolymer as a main component as the heat welding layer, the amount of volatile gas is larger than that in the case of using another polymer as a main component regardless of whether or not the PP film is stretched. Can be reduced.

Here, in this embodiment, the phrase "polypolymer as a main component" in the PP film means that the proportion of the homopolymer (homo-PP) of PP is the largest among the polymer components that are the main components of the PP film. That is, the ratio of the components other than the homo-PP in the polymer component may be any ratio as long as it is possible to keep the amount of volatile gas in the heat-welded layer within a predetermined range described later.
Specifically, it is sufficient that the content of the unit other than the propylene unit contained in the polymer component is small, and the content of the unit other than the propylene unit is 1. It is preferably 0% by mass or less, more preferably 0.5% by mass or less, and further preferably 0.3% by mass or less. It is particularly preferable that the content of the unit other than the propylene unit is 0% by mass, that is, the polymer component of the PP film is only homo-PP.
The details of the provision of "mainly homopolymer" such as an example of a unit other than the propylene unit in the polymer component and a method of calculating the content of the unit other than the propylene unit in the polymer component are described above. Since it is the same as the details of the provision that "the polymer component contains a homopolymer as a main component" described in the section of "I. First aspect 1. Heat welding layer", the description thereof is omitted here.

In this embodiment, the heat-welded layer may contain homo-PP as a main component in the polymer component, may contain only homo-PP as the polymer component, and may contain a unit other than the propylene unit in the polymer component. As long as the amount is within the above range, a copolymer such as block PP or random PP may be contained in addition to homo PP as a polymer component. Further, the heat-welded layer may contain additives such as an anti-blocking agent, a lubricant, a flame retardant, and an organic filler in addition to the polymer component. The amount of the additive is not particularly limited as long as the polymer component is the main component in the heat welding layer, and can be, for example, 3% by mass or less with respect to 100% by mass of the total mass of the PP film.

Further, in this embodiment, the heat-welded layer may be a stretched polypropylene film (OPP film) or a non-stretched polypropylene film (CPP film) as long as it contains a homopolymer as a main component. Of these, a CPP film is preferable from the viewpoint of excellent heat sealability.

In this embodiment, the amount of volatile gas in the heat-welded layer at 90 ° C. is preferably 15 mg / m ² or less, particularly 10 mg / m ² or less, particularly 5 mg / m ² or less. The reason is as described in the above section "I. First aspect 1. Heat welding layer". The amount of volatile gas at 90 ° C. can be quantified by the method described in the above section "I. First aspect 1. Heat welding layer", and can be at least the amount of organic components.

The heat welding layer in the present embodiment, in the infrared absorption spectrum, to the peak intensity of the absorption peak peak intensity is maximum around 1380 cm ^-1, a peak intensity at a wave number region of from 700 cm ^-1 to 790 cm ^-1 is a maximum The ratio of the peak intensities of a certain absorption peak is preferably 0.05 or less, and more preferably 0.04 or less, particularly 0.03 or less. Of these to the peak intensity of the absorption peak peak intensity is maximum around 1380 cm ^-1, the ratio of the peak intensity of the absorption peak peak intensity is maximum around 725 cm ^-1 is preferably at 0.05 or less, preferably It is preferably 0.04 or less, particularly 0.03 or less. The reason is the same as the reason explained in the above section "I. First aspect 1. Heat welding layer".

Here, the vicinity of 1380 cm ^-1, means a tolerance relative to the 1380 cm ^-1, it can be a wave number region of 1380cm ^-1 ± 10cm ^-1. Above all, it is preferable to set the wave number region to ^{1380 cm -1} ± 5 cm ^-1. Further, the vicinity of 725 cm ^-1, means a tolerance relative to the 725 cm ^-1, it can be a wave number region of 725cm ^-1 ± 25cm ^-1. The permissible range may be ± 20 cm ^-1 , ± 15 cm ^-1 , or ± 10 cm ^-1 .

In the above-wave band region, when two or more absorption peak appears, the heat welding layer in the present embodiment, in the infrared absorption spectrum, the maximum peak intensity in the wave number region of from 700 cm ^-1 to 790 cm ^-1 A certain absorption peak (sometimes referred to as the maximum absorption peak) and the absorption peak having the second highest peak intensity (sometimes referred to as the second maximum absorption peak) are the first absorption peak and the second absorption peak from the low wavenumber side. When the absorption peak is defined as ^{the absorption peak and the absorption peak having the maximum peak intensity near 1380 cm -1 is} defined as the third absorption peak, the first absorption peak and the second absorption peak have the same as the peak intensity of the third absorption peak. The ratio of at least one of the peak intensities is preferably 0.05 or less, and more preferably 0.04 or less, particularly 0.03 or less.
Among them ^{, the absorption peak having the maximum peak intensity near 725 cm -1} and the absorption peak having the second highest peak intensity are defined as the first absorption peak and the second absorption peak from the low wavenumber side, and the peak intensity is around ^{1380 cm -1.} When the maximum absorption peak is defined as the third absorption peak, the ratio of the peak intensity of at least one of the first absorption peak and the second absorption peak to the peak intensity of the third absorption peak is 0. It is preferably 05 or less, and more preferably 0.04 or less, particularly 0.03 or less.
The reason is the same as the reason explained in the above section "I. First aspect 1. Heat welding layer".

At least one of the first peak intensity ratio and the second peak intensity ratio may be within the above range, and in particular, the first peak intensity ratio and the second peak intensity ratio may be within the above range, respectively. preferable.

Further, in the present embodiment, in the heat welding layer, the absorption peak having the maximum peak intensity near ^{720 cm -1} is set as the first absorption peak, and the absorption peak having the maximum peak intensity near ^{730 cm -1 is set as the second absorption peak.} , 1380 cm ^-1 , when the absorption peak with the maximum peak intensity is defined as the third absorption peak, at least one of the first absorption peak and the second absorption peak with respect to the peak intensity of the third absorption peak. The ratio of the peak intensities is preferably 0.05 or less, and more preferably 0.04 or less, particularly 0.03 or less. At this time, at least one of the first peak intensity ratio and the second peak intensity ratio may be within the above range, but among them, the first peak intensity ratio and the second peak intensity ratio are each described above. It is preferable that it is within the range of. The reason is the same as the reason explained in the above section "I. First aspect 1. Heat welding layer".

Here, the vicinity of 720 cm ^-1, can be a wave number region of 720cm ^-1 ± ^{5cm -1,} it is preferably a wave number region of inter alia 720cm ^-1 ± ^{2cm -1.} Further, the vicinity of the 730 cm ^-1, can be a wave number region of 730 cm ^-1 ± ^{5 cm -1,} it is preferably a wave number region of inter alia 730cm ^-1 ± ^{2cm -1.}

The infrared absorption spectrum of the heat-welded layer in this embodiment can be measured by a single reflection ATR measurement method using a Fourier transform infrared spectrophotometer (FT-IR). The measuring method is as described in the above section "I. First aspect 1. Heat welding layer". In addition, the details of the infrared absorption spectrum of the heat-welded layer in this embodiment are as described in the above section "I. First aspect 1. Heat-welded layer".

In this aspect, the thickness of the heat-welded layer can be the same as the thickness described in the section "I. First aspect 1. Heat-welded layer". A commercially available film may be used for the heat welding layer, and a polypropylene resin containing homopolymer as a main component, which is obtained by polymerizing propylene by a known method, is used and molded into a sheet by extrusion or the like. You may use the body. The molded product may be unstretched or may be stretched.

B. Vacuum heat insulating material Next, the vacuum heat insulating material of the present invention will be described. 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 the vacuum heat insulating material that encloses the core material, and the outer packaging material for the vacuum heat insulating material includes a heat welding layer, a barrier layer and an outer packaging material for the vacuum heat insulating material. The heat-welded layer has a protective layer in this order, and the heat-welded layer is a non-stretched polypropylene film containing a homopolymer.

Further, another aspect of 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 the vacuum heat insulating material that encloses the core material, and the outer packaging material for the vacuum heat insulating material is heat. The heat-welded layer has a welded layer, a barrier layer, and a protective layer in this order, and the heat-welded layer is a polypropylene film containing a homopolymer as a main component.

The vacuum heat insulating material of the present invention can be the same as that illustrated in FIG. 2 which has already been described. According to the present invention, the vacuum heat insulating material outer packaging material is the vacuum heat insulating material outer packaging material of the present invention, so that the vacuum heat insulating material maintains its heat insulating performance for a long period of time in a high temperature environment or at room temperature. It is possible to form a vacuum heat insulating material that can form a vacuum heat insulating material.

The vacuum heat insulating material of the present invention has at least an outer packaging material for the vacuum heat insulating material and a core material.
Hereinafter, the vacuum heat insulating material of the present invention will be described for each configuration.

1. 1. Outer packaging material for vacuum heat insulating material The outer packaging material for vacuum heat insulating material in the present invention encloses the core material. The outer packaging material for the vacuum heat insulating material is the above-mentioned outer packaging material for the vacuum heat insulating material of the present invention. The description of the outer packaging material for the vacuum heat insulating material can be the same as that described in the section "A. Outer packaging material for the vacuum heat insulating material", and thus the description thereof is omitted here.
The term "sealing" means that the bag is sealed inside a bag formed by using the outer packaging material.

The outer packaging material for the vacuum heat insulating material in the present invention may be the first aspect or the second aspect described in the section of "A. Outer packaging material for vacuum heat insulating material".

2. Core material The core material in the present invention is sealed by the above-mentioned outer packaging material for vacuum heat insulating material.
The core material preferably has low thermal conductivity. The core material is preferably a porous material having a porosity of 50% or more, particularly 90% or more.

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

Further, as the foam, there are urethane foam, styrene foam, phenol foam and the like, and among these, a foam that forms open cells is preferable.

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

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

3. 3. Vacuum heat insulating material The vacuum heat insulating material of the present invention is a vacuum heat insulating material in which the inside enclosed with the outer packaging material for the vacuum heat insulating material is vacuum-sealed under reduced pressure. 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, the heat conduction due to the convection of the air remaining inside can be reduced, and excellent heat insulating properties can be exhibited.

Further, the thermal conductivity of the vacuum heat insulating material is preferably low. For example, the thermal conductivity (initial thermal conductivity) of the vacuum heat insulating material at 25 ° C. is preferably 5 mW / m · K or less. It is preferably 4 mW / m · K or less, and particularly preferably 3 mW / m · K or less. By setting the thermal 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, so that a high heat insulating effect can be obtained. Further, the thermal conductivity of the vacuum heat insulating material after deterioration at 90 ° C. for 1000 hours is preferably 15 mW / m · K or less, and more preferably 11.5 mW / m · K or less. The thermal conductivity can be a value measured by a heat flow metering method using a thermal conductivity measuring device according to JIS-A-1412-2. Examples of the thermal conductivity measuring device include a thermal conductivity measuring device Autolambda (product name HC-074, manufactured by Eiko Seiki Co., Ltd.).

Specifically, the above-mentioned thermal conductivity is measured by a method based on JIS A1412-2: 1999 (Method for measuring thermal resistance and thermal conductivity of thermal insulating material-Part 2: Heat flow metering method (HFM method)). It can be measured under the following conditions using a thermal conductivity measuring device (for example, a thermal conductivity measuring device Autolambda HC-074 (manufactured by Eiko Seiki Co., Ltd.)). The measurement is performed by arranging both main surfaces of the measurement sample (vacuum heat insulating material) to face in the vertical direction. Before measuring the thermal conductivity, it is preferable to measure in advance whether the temperature of the measurement sample is equal to the measurement environment temperature by using a heat flow meter or the like. Under one condition, at least three samples are measured, and the average of those measurements is taken as the value of thermal conductivity under that condition.
(Measurement conditions for thermal conductivity)
-Measurement sample: width 29 cm ± 0.5 cm, length 30 cm ± 0.5 cm
・ Time required for steady test: 15 minutes or more ・ Standard plate type: EPS
・ Temperature of high temperature surface: 30 ℃
・ Temperature of low temperature surface: 10 ℃
-Average temperature of the measurement sample: 20 ° C

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 the intrusion of moisture, oxygen, etc. 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 section "A. Outer packaging material for vacuum heat insulating material I. First aspect 2. Barrier layer". The description in is omitted.

4. Manufacturing Method As the manufacturing method of the vacuum heat insulating material of the present invention, a general method can be used. For example, the above-mentioned outer packaging material of the present invention is prepared in advance, two of the above-mentioned outer packaging materials are opposed to each other so that their respective heat-welding layers face inward, and the above-mentioned core material is arranged between them. By heat-welding the ends of the outer packaging materials on the remaining three sides with one of the outer circumferences of the core material as an opening, a bag body formed of the two outer packaging materials and having the core material arranged inside is prepared. Then, the bag body is attached to the vacuum sealer, and the opening is sealed with the internal pressure of the bag body reduced, so that the core material is sealed by the outer packaging material. Is obtained.

Further, in the above manufacturing method, one piece of the outer packaging material is opposed so that the heat welding layer faces inward, the core material is arranged between them, 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 to each other, a bag body formed by one of the outer packaging materials and having the core material arranged inside is prepared, and then the bag body is prepared. Is attached to a vacuum sealer, and the opening is sealed with the internal pressure of the bag reduced, so that a vacuum heat insulating material in which the core material is sealed by the outer packaging material can be obtained. good.

5. 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 vacuum heat insulating material can be used in a part that requires heat insulation, such as a part that has a heat source and generates heat, or a part that becomes hot due to being heated from the outside. Applications of the present invention include, for example, the equipment described in "C. Equipment with Vacuum Insulating Material", a cooler box, a transportation container, a fuel tank for hydrogen, a system bath, a hot water tank, a heat insulator, a residential wall, an automobile, and the like. Examples include airplanes, ships, trains, etc.

C. Article with vacuum heat insulating material Next, the article with vacuum heat insulating material of the present invention will be described. The article with the vacuum heat insulating material of the present invention is an article having a heat insulating region and an article with a vacuum heat insulating material provided with the vacuum heat insulating material, and the vacuum heat insulating material is a core material and a vacuum heat insulating material that encloses the core material. The outer packaging material for the vacuum heat insulating material has a heat-welding layer, a barrier layer and a protective layer in this order, and the heat-welding layer is a non-stretched polypropylene film containing a homopolymer. It is characterized by being.

Further, another aspect of the article with the vacuum heat insulating material of the present invention is an article having a heat insulating region and an article with a vacuum heat insulating material provided with the vacuum heat insulating material, wherein the vacuum heat insulating material is a core material and the core material. The vacuum heat insulating material outer packaging material has a heat-welding layer, a barrier layer and a protective layer in this order, and the heat-welding layer mainly contains a homopolymer. It is characterized by being a polypropylene film as a component.

According to the present invention, the vacuum heat insulating material provided in the article is a vacuum heat insulating material using the outer packaging material described in the section "A. Outer packaging material for vacuum heat insulating material", and is used in a high temperature environment or at room temperature for a long period of time. Since the heat insulating performance can be maintained, the article can be an article having good heat insulating performance.

Here, the heat-insulated region is a region that is heat-insulated by the vacuum heat insulating material, for example, a region that is heat-retained or cooled, a region that surrounds the heat source or the cooling source, or a region that is isolated from the heat source or the cooling source. Is. These areas may be spaces or objects.

Examples of articles include electric devices such as refrigerators, freezers, warmers, and coolers, heat-retaining containers, cold-retaining containers, transport containers, containers, storage containers and other containers, vehicles, aircraft, ships and other vehicles, houses, warehouses, etc. Examples include building materials such as buildings, wall materials, and floor materials.

Specific examples of the article with the vacuum heat insulating material of the present invention include a device having a heat source portion or a heat insulating portion inside the main body or the inside, and a device with a vacuum heat insulating material provided with the vacuum heat insulating material. Here, the "heat source unit" refers to a portion that generates heat in the main body of the device or inside the device when the device itself is driven, and refers to, for example, a power supply or a motor. Further, the "heat-insulated portion" refers to a portion where the device itself or the inside does not have a heat source section, but the device receives heat from an external heat source and becomes hot.

According to the present invention, the vacuum heat insulating material is the vacuum heat insulating material of the present invention, and the heat insulating performance can be maintained for a long period of time in a high temperature environment or at room temperature. The vacuum heat insulating material insulates the heat from the heat source part to prevent the temperature of the entire device from becoming high, while in the device having the heat insulating part, the temperature state of the heat insulating part is controlled by the vacuum heat insulating material. Can be kept. As a result, it is possible to obtain a device having high energy saving characteristics with reduced power consumption.

Since the vacuum heat insulating material in the present invention is the same as the content described in the above-mentioned section "B. Vacuum heat insulating material", the description thereof is omitted here.

The device in the present invention has a heat source portion or a heat-retaining portion inside the main body or the main body, and among them, at least has a heat source portion or a heat-retaining portion that reaches a high temperature in the range of 80 ° C. to 150 ° C. Is preferable. Examples of the equipment in the present invention include electric equipment such as a natural refrigerant heat pump water heater (registered trademark "EcoCute"), a refrigerator, a vending machine, a rice cooker, a pot, a microwave oven, a commercial oven, an IH cooking heater, and an OA equipment. Examples include automobiles. Above all, in the present invention, the above-mentioned equipment is a natural refrigerant heat pump water heater, a commercial oven, a microwave oven, and an automobile, and it is preferable that the above-mentioned vacuum heat insulating material of the present invention is used.

As a mode of attaching the vacuum heat insulating material to the device, the vacuum heat insulating material may be directly attached to the heat source portion or the heat insulating portion of the device, and the vacuum heat insulating material may be attached between the heat insulating portion and the heat source portion or the external heat source. It may be attached so as to sandwich the.

The present invention is not limited to the above embodiment. The above embodiment is an example, and any one having substantially the same configuration as the technical idea described in the claims of the present invention and exhibiting the same effect and effect is the present invention. It is included in the technical scope of the invention.

Hereinafter, the present invention will be described in more detail with reference to Examples.

[Example]
(Preparation of interlayer adhesive)
A polyester-based main agent, a curing agent containing an aliphatic polyisocyanate, and ethyl acetate are mixed so that the weight mixing ratio is main agent: curing agent: ethyl acetate = 10: 1:10, and two-component curing is performed. A mold interlayer adhesive was prepared.

(Preparation of outer packaging material for vacuum heat insulating material)
An outer packaging material having a layer structure of a heat welding layer / barrier layer / first protective layer / second protective layer was prepared. In addition, "/" in the said layer structure indicates a laminated interface.
As the heat welding layer, a CPP film containing a homopolymer (thickness: 50 μm, product name: Trefan 3301, manufactured by Toray Film Processing Co., Ltd.) was used. As the barrier layer, an aluminum foil (Al thickness 6 μm, product name: 8021, manufactured by UACJ Foil Corporation) was used. A nylon film (thickness: 25 μm, product name: Emblem ONBC, manufactured by Unitika Ltd.) is used as the first protective layer, and a PET film (thickness: 12 μm, product name: Emblem PTMB, manufactured by Unitika Ltd.) is used as the second protective layer. Made by) was used.
Each of the above layers is formed by applying an interlayer adhesive prepared in the above-mentioned compounding ratio on the surface of the lower layer using a die coater so as to ^{have a coating amount of 3.5 g / m 2 and drying the layers.} It was laminated by laminating the layers.

(Making vacuum heat insulating material)
Two of the obtained outer packaging materials were stacked and heat-sealed in three rectangular directions to prepare a bag body in which only one direction was open. Glass wool having a size of 300 mm × 300 mm × 30 mm was used as the core material, and after drying, the core material was stored in the bag body and the inside of the bag body was evacuated. Then, the opening portion of the bag body was sealed with a heat seal to obtain a vacuum heat insulating material. The ultimate pressure was 0.05 Pa.

[Comparative Example 1]
An external packaging material was prepared and obtained in the same manner as in the above Examples except that a CPP film containing a random copolymer (thickness: 50 μm, product name: Trefan 3951, manufactured by Toray Film Processing Co., Ltd.) was used as the heat welding layer. A vacuum heat insulating material was produced in the same manner as in the above-mentioned example using the outer packaging material.

[Comparative Example 2]
An outer packaging material was prepared and obtained in the same manner as in the above Examples except that a CPP film containing a block copolymer (thickness: 50 μm, product name: Trefan ZK99S, manufactured by Toray Film Processing Co., Ltd.) was used as the heat welding layer. A vacuum heat insulating material was produced in the same manner as in the above-mentioned example using the outer packaging material.

[Evaluation 1]
The thermal conductivity of the vacuum heat insulating materials obtained in Examples and Comparative Examples 1 and 2 was measured. The thermal conductivity of each vacuum heat insulating material was set to a value measured by a heat flow meter method using a thermal conductivity measuring device in accordance with JIS A1412-2. As the thermal conductivity measuring device, a thermal conductivity measuring device Autolambda (product name HC-074, manufactured by Eiko Seiki Co., Ltd.) was used. Specifically, using the above-mentioned thermal conductivity measuring device, with both main surfaces of the constant sample arranged so as to face in the vertical direction, JIS A 1412-2: 1999 (thermal resistance and thermal conductivity of the thermal insulating material). Method of measuring the rate-Part 2: The measurement was performed under the following measurement conditions by a method based on the thermal flow meter method (HFM method). Under one condition, three samples were measured and the average of those measurements was taken as the value of thermal conductivity. The measurement results are shown in FIG.
(Measurement conditions for thermal conductivity)
-Measurement sample: width 29 ± 0.5 cm, length 30 ± 0.5 cm
・ Time required for steady test: 15 minutes or more ・ Standard plate type: EPS
・ Temperature of high temperature surface: 30 ℃
・ Temperature of low temperature surface: 10 ℃
-Average temperature of the measurement sample: 20 ° C

From the measurement results of the thermal conductivity of the vacuum heat insulating material, the examples in which the CPP film containing a homopolymer was used as the heat welding layer were compared with Comparative Example 1 using a random copolymer and Comparative Example 2 using a block copolymer. It can be seen that the thermal conductivity is low even after a long period of time, and the heat insulating performance is maintained high for a long period of time. The low thermal conductivity even after a long period of time means that the degree of vacuum inside the vacuum heat insulating material does not change with time, and by using a homopolymer CPP film, another CPP film can be used. It can be seen that the degree of vacuum can be maintained for a longer period of time than in the case of the case.

[Reference evaluation]
Infrared absorption spectra were measured by a single reflection ATR measurement method using a Fourier transform infrared spectrophotometer (FT-IR) for various CPP films used as the heat welding layer in Examples and Comparative Examples 1 and 2. The absorption peak having the maximum peak intensity in the wave number region of 720 ± 5 cm ^-1 is defined as the first absorption peak B, and the absorption peak having the maximum peak intensity in the wave number region of ^{730 ± 5 cm -1 is defined as the second absorption peak C.} The absorption peak having the maximum peak intensity in the wave number region of 1380 ± 10 cm ^{-1 was defined as the third absorption peak A.} The infrared absorption spectrum (FT-IR) measurement is performed by the method for measuring the infrared absorption spectrum of the heat-welded layer described in the above section "A. Outer packaging material for vacuum heat insulating material I. First aspect 1. Heat-welded layer". It was done according to the conditions.
I _B and the peak intensity of the first absorption _peak, the peak intensity of the second absorption peak I _C, the peak intensity of the third absorption peak as I _A, the various CPP film, the peak intensity of the third absorption peak I peak intensity ratio _I B / _{I a} of the peak intensity _{I B} of the first absorption peak for _a, and the peak intensity ratio of the peak intensity _{I C} of the third second absorption peak to the peak intensity _{I a} of the absorption peak _I C / _{I a} Were calculated respectively (Reference Examples 1 to 3). Similarly, the infrared absorption spectrum of the homo PP film (thickness: 40 μm, product name: SC40, manufactured by Mitsui Chemicals Tocello Co., Ltd.) and polyethylene film (thickness: 50 μm, product name: HC-E, manufactured by Mitsui Chemicals Toshiro Co., Ltd.) It was measured, to calculate the peak intensity ratio _I B / _{I a} and _I C / _{I a} (reference example 4-5). The results are shown in Table 1 and FIG. FIG. 7B is an enlarged view of the wavy line portion of FIG. 7A.
The first absorption peak B of Reference Examples 1 and 2, the second absorption peak C of Reference Example 3-5, respectively, in the infrared absorption spectrum of the PP film used in each Example, 790 cm from 700 cm ^{-1 -} It corresponded to the maximum absorption peak in the wave number region up to ^1.

Further, for each PP film of Reference Examples 1 to 5, the amount of volatile gas (organic) at 90 ° C. by the method described in the above section "A. Outer packaging material for vacuum heat insulating material I. First aspect 1. Heat welding layer". The amount of components) was measured. The results are shown in Table 1.

From the above results, homo PP film in which Example 1 and the peak intensity ratio _I B / _{I A} and _I C / _{I A} of Reference Example 4 are both 0.03 or less, reference examples containing PE 2 to 3 and showed a small value PE film and is compared with the peak intensity ratio _I B / _{I a} and _I C / _{I a} of reference example 5. From this result, it was suggested that Reference Example 1 and Reference Example 4 did not contain PE or had an extremely low PE content (the polymer component contained homo-PP as a main component). Further, from the measurement results of the amount of volatile gas using the homo PP similar to Table 1 and Reference Example 4 (FIGS. 3 and 4), the homo PP film was compared with the block PP film containing PE and the random PP film. It was suggested that the amount of volatile gas generated was very small.

The first absorption peak B of Reference Examples 1 and 2, the second absorption peak C of Example 3 to 5, respectively, the PP film used in each reference example, in the wave number region of from 700 cm ^-1 to 790 cm ^-1 Corresponds to the maximum absorption peak. 1380 maximum absorption peak at a wave number region of ± 10 cm ^-1 maximum ratio of the peak intensity of the absorption peak (reference example to the peak intensity _{I A,} in the wave number region of from 700 meters ^-1 to 790 cm ^-1 of the (third absorption peak) _I B / _{I a} in 1,2, even when comparing the _I C / _{I a)} in reference example 3-5, the peak intensity ratio of the homo-PP films in which reference examples 1 and 4, the copolymer The values were lower than the peak intensity ratios of Reference Examples 2 and 3 which are PP films contained and Reference Examples 5 which are PE films. Further, in the PP film, it was confirmed that the smaller the peak intensity ratio, the smaller the amount of volatile gas generated.

From these results, it is possible to maintain the degree of vacuum inside the vacuum heat insulating material by using a homo-PP film with a small amount of volatile gas generated in the heat-welded layer in the outer packaging material for the vacuum heat insulating material, and other PPs. It was suggested that the degree of vacuum was maintained higher for a longer period of time than when the film was used. That, PP film ratio of the maximum absorption peak at a wave number region of from 700 meters ^-1 to the peak intensity of the maximum absorption peak at around 1380 cm ^-1 to 790 cm ^-1 becomes less than the predetermined value, homo PP is a main component It was confirmed that it is suitable for a heat-weldable film in the outer packaging material for vacuum heat insulating material. Further, to the peak intensity of the maximum absorption peak at around 1380 cm ^-1, 720 cm peak intensity ratio of the maximum absorption peak in the vicinity of ^-1 _I B / _{I A,} and, to the peak intensity of the maximum absorption peak at around 1380 cm ^-1 , 730 cm ratio _I C / _{I a} of the peak intensity of the maximum absorption peak in the vicinity of _{^-1, I B / I a ≦ 0.05} , PP film to be _I C / I _a ≦ 0.05 is little PE It was confirmed that homo-PP was the main component without containing it, suggesting that it is suitable for a heat-weldable film in the outer packaging material for vacuum heat insulating materials.

1, 1A, 1B ... Heat welding layer 2, 2A, 2B, ... Barrier layer 3, 3A, 3B ... Protective layer 10, 10A, 10B ... Outer packaging material for vacuum heat insulating material (outer packaging material)
11 ... Core material 20 ... Vacuum heat insulating material

Claims (6)

An outer packaging material for a vacuum heat insulating material having a heat welding layer, a barrier layer and a protective layer in this order.
The heat welding layer may Ri polypropylene film der composed mainly of homopolymers,
The heat welding layer is, in the infrared absorption spectrum, with respect to the peak intensity of the absorption peak peak intensity is maximum in the wave number region of 1380 ± 10 cm ^-1, a peak intensity at a wavenumber region from 700 meters ^-1 to 790 cm ^-1 An outer packaging material for a vacuum heat insulating material in which the ratio of the peak intensities of the maximum absorption peaks is 0.05 or less. An outer packaging material for a vacuum heat insulating material having a heat welding layer, a barrier layer and a protective layer in this order.
The heat-welded layer is a polypropylene film containing a homopolymer as a main component.
The heat welding layer is, in the infrared absorption spectrum, the absorption peak peak intensity is maximum and first absorption peak at a wave number region of 720 cm ^-1 ± ^{5 cm -1,}
The absorption peak with the maximum peak intensity in the wave number region of ^{730 cm -1} ± 5 cm ^{-1 is defined as the second absorption peak.}
When the absorption peak with the maximum peak intensity in the wave number region of 1380 ± 10 cm ^{-1 is set as the third absorption peak,}
An external packaging material for a vacuum heat insulating material, wherein the ratio of the peak intensity of at least one of the first absorption peak and the second absorption peak to the peak intensity of the third absorption peak is 0.05 or less. The packaging material for a vacuum heat insulating material according to claim 1 or 2, wherein the amount of volatile gas of the polypropylene film at 90 ° C. is 15 mg / m ² or less. The ratio of the peak intensity of the first absorption peak to the peak intensity of the third absorption peak and the ratio of the peak intensity of the second absorption peak to the peak intensity of the third absorption peak are 0.05, respectively. The outer packaging material for a vacuum heat insulating material according to claim 2 , which is as follows. A vacuum heat insulating material having a core material and an outer packaging material for the vacuum heat insulating material that encloses the core material.
The vacuum heat insulating material outer packaging material is the vacuum heat insulating material outer packaging material according to any one of claims 1 to 4.
Vacuum heat insulating material. An article having a heat insulating region and an article with a vacuum heat insulating material provided with the vacuum heat insulating material.
The vacuum heat insulating material has a core material and an outer packaging material for the vacuum heat insulating material that encloses the core material.
An article with a vacuum heat insulating material, wherein the outer packaging material for the vacuum heat insulating material is the outer packaging material for the vacuum heat insulating material according to any one of claims 1 to 4.

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