JP6098306B2 - Vacuum insulation material - Google Patents

Description

  The present invention relates to an exterior material for a vacuum heat insulating material.

  The vacuum heat insulating material is a heat insulating material whose heat insulating performance is enhanced by wrapping the core material with an exterior material, making the periphery of the core material in a vacuum state, and bringing the thermal conductivity of the gas as close to zero as possible.

  The exterior material is required to have a gas barrier property in order to maintain the degree of vacuum inside. However, since the conventional vacuum heat insulating material configured as described above uses aluminum foil as a gas barrier film, the heat insulation of the vacuum heat insulating material by the heat conduction that travels through the vacuum heat insulating material, the so-called heat bridge phenomenon. The effect is reduced.

  Therefore, in order to solve the heat bridge phenomenon, there is a vacuum heat insulating material using an exterior material in which a gas barrier film is changed to a gas barrier film having a vapor deposition film instead of a metal foil (for example, Patent Document 1).

  In this vacuum heat insulating material, it is desirable to laminate a plurality of gas barrier films in order to improve the gas barrier property of the exterior material (cover material), and in order to complement gaps and defects in the deposited material on the vapor deposition surface, It is considered desirable to laminate so that the vapor deposition surfaces of the conductive film face each other.

  However, in the fin portion composed of the seal portion of the end portion of the exterior material of the vacuum heat insulating material and the portion where the core material does not exist and the exterior material is in close contact when the vacuum is applied in the vicinity thereof, the core material is contained. Since the heat insulation performance is lower than that of the portion, the fin portion is bent to maintain the heat insulation performance. There is a problem that pinholes are generated during the bending, and the function as a vacuum heat insulating material is impaired.

  Known documents are shown below.

JP 2010-138956 A

  The present invention has been made in view of the above-described circumstances, and the vacuum insulation material is highly flexible so that it can maintain a high vacuum state even if the vacuum insulation material is used for a long period of time. It is an issue to provide.

The invention according to claim 1 of the present invention is, in order from the outside, a vacuum heat insulating material exterior material comprising a base material layer, a barrier layer, and a sealant layer,
A stretched polypropylene film and a stretched nylon film were laminated on the base material layer, the stretched polypropylene film was disposed on the outer surface side, and a vapor deposition film of metal or metal oxide was used for the barrier layer. It is the exterior material of the vacuum heat insulating material characterized by these.

The vacuum insulation material of the present invention has the above-described configuration, and uses a stretched polypropylene film and a stretched nylon film for the base material layer, and the stretched polypropylene film is disposed on the outer surface side. Because it is highly flexible, even if it is used for a long time,
The vacuum heat insulating material can be maintained in a high vacuum state.

  The invention according to claim 2 of the present invention is characterized in that an aluminum-deposited polyethylene terephthalate film and an aluminum-deposited ethylene-vinyl alcohol copolymer film are laminated on the barrier layer. It is an exterior material for a heat insulating material.

  The exterior packaging material of the vacuum heat insulating material of the present invention uses an aluminum vapor-deposited polyethylene terephthalate film and an aluminum vapor-deposited ethylene-vinyl alcohol copolymer film for the barrier layer. Therefore, the barrier property is extremely high, and the vacuum state of the vacuum heat insulating material is reduced. It can be kept high and pinholes are less likely to occur because no metal foil is used. Moreover, the heat bridge phenomenon does not occur.

The invention according to claim 3 of the present invention is the vacuum according to claim 1 or 2, wherein a linear low density polyethylene film having a density of 0.935 g / cm ³ or less is used for the sealant layer. It is an exterior material for a heat insulating material.

Since the vacuum insulating material of the present invention uses a linear low-density polyethylene film having a density of 0.935 g / cm ³ or less for the sealant layer, the sealant layer is also flexible, and the vacuum heat insulating material. The bending resistance as an exterior material is also improved.

  Since the vacuum insulation material of the present invention is excellent in bending resistance, the vacuum insulation material using the vacuum insulation material can maintain a high vacuum state even when used for a long period of time. And heat insulation performance can be maintained.

It is sectional drawing which showed typically an example of the exterior material of the vacuum heat insulating material of this invention. It is sectional drawing which showed typically the vacuum heat insulating material using an example of the exterior material of the vacuum heat insulating material of this invention. It is sectional drawing explaining the bending part of the vacuum heat insulating material which used an example of the exterior material of the vacuum heat insulating material of this invention. It is the top view which showed typically the vacuum heat insulating material using an example of the exterior material of the vacuum heat insulating material of this invention.

Hereinafter, embodiments for carrying out the present invention will be described.
FIG. 1 is a cross-sectional view schematically showing an example of the vacuum insulation material of the present invention.

  The vacuum insulation material 1 of this example is composed of a base material layer 10, a barrier layer 20, and a sealant layer 30 in this order from the outside. The base material layer 10 is composed of a stretched polypropylene film 11 on the outer surface and a stretched nylon film 12 on the inside. By using such a two-layer base material layer 10, high bending resistance can be obtained. Although the stretched polypropylene film 11 has high bending resistance, the abrasion resistance is also improved by forming the stretched polypropylene film 11 on the outer surface. By using the stretched nylon film 12, the toughness is increased and the bending resistance is improved.

For the barrier layer 20, not a metal foil but a metal vapor-deposited film or an inorganic oxide vapor-deposited film can be used. Thereby, the heat bridge phenomenon can be solved. Moreover, the generation of pinholes can be suppressed. As for the thickness of the film used for a vapor deposition film, 9-25 micrometers is preferable. In particular, using two aluminum vapor deposition films for the barrier layer 20, the barrier layer 20 having a two-layer structure consisting of an aluminum vapor deposition polyethylene terephthalate film 21 and an aluminum vapor deposition ethylene-vinyl alcohol copolymer film 22 is formed from the outside. By doing so, an extremely high barrier property can be obtained.

For the sealant layer 30, various polyethylene resins, polypropylene, and the like can be used. In particular, it is preferable to use a linear low density polyethylene film having a density of 0.935 g / cm ³ or less. The thickness is preferably 30 to 80 μm. If the density is higher than 0.935 g / cm ³ , for example, if the density is as high as 0.94 g / cm ³ , the bending resistance is deteriorated, which is not preferable.

  As a method of laminating each layer constituting the vacuum heat insulating material exterior material 1 of this example, a method by dry lamination using a two-component curable urethane adhesive and a method by extrusion lamination can be adopted.

  Hereinafter, a method of creating the vacuum heat insulating material 2 using the vacuum heat insulating material 1 of this example will be described.

  First, the two rectangular vacuum insulation materials 1 are sealed with the sealant layer 30 faced, three sides are heat-sealed in a bag shape, the core material 3 is inserted therein, and the vacuum is drawn to open the opening. It heat-seals and the heat sealing | fusion part 4 is provided in a periphery.

  As the core material 3, an inorganic fiber such as glass fiber or an organic fiber such as polystyrene fiber can be used. Moreover, what solidified powder and made into a board and a foamed resin can also be used.

  When the core material 3 is inserted and evacuated to provide the heat fusion part 4, the heat fusion part 4 and the core material 3 are separated as shown in the cross-sectional view of FIG. A close contact portion 5 in which the front and back exterior materials 1 are in direct contact is formed. In the close contact part 5 and the heat fusion part 4, heat insulation cannot be expected.

  Therefore, as shown in the cross-sectional view of FIG. 3, the close contact portion 5 and the heat fusion portion 4 are bent to the outside air side so as not to come to the cold insulation or heat insulation side. A portion where the close contact portion 5 and the heat fusion portion 4 are bent is stopped with a flame retardant tape 6 as shown in FIG. Thus, a vacuum heat insulating material is completed.

  Even if the bent portion is made in this way, the vacuum insulation material 1 of the vacuum insulation material of this example is used, so the bending insulation is high and the vacuum insulation material is kept in a high vacuum state even when used for a long period of time. can do.

  Specific examples of the present invention will be described below.

<Example 1>
Stretched polypropylene film 11 having a thickness of 20 μm and stretched nylon film 12 having a thickness of 15 μm as the base material layer 10, an aluminum-deposited polyethylene terephthalate film 21 having a thickness of 12 μm and an aluminum-deposited ethylene-vinyl alcohol copolymer having a thickness of 15 μm as the barrier layer 20. The united film 22 was laminated and bonded in this order by a dry lamination method using a two-component curable urethane adhesive.

Subsequently, the sealant layer 30 having a thickness of 50 μm and a linear low density polyethylene film having a density of 0.923 g / cm ³ and an aluminum-deposited ethylene-vinyl alcohol copolymer film surface of the laminate are two-component curable. Using a urethane-based adhesive, bonding is performed by a dry lamination method to produce a vacuum heat insulating material exterior material 1 composed of a base material layer 10, a barrier layer 20, and a sealant layer 30, and the vacuum heat insulating material of Example 1 An exterior material was obtained.

  Below, the comparative example of this invention is demonstrated.

<Comparative Example 1>
A vacuum heat insulating outer packaging material of Comparative Example 1 was produced in the same manner as in Example 1 except that the stretched polypropylene film 11 was not used for the base material layer and only the stretched nylon film 12 was used.

<Comparative example 2>
A vacuum heat insulating material exterior material of Comparative Example 2 was produced in the same manner as in Example 1 except that the stretched nylon film 12 was not used for the base material layer and only the stretched polypropylene film 11 was used.

<Comparative Example 3>
Comparative Example 3 was performed in the same manner as in Example 1 except that an aluminum foil having a thickness of 7 μm was used instead of the aluminum-deposited polyethylene terephthalate film 21 and the aluminum-deposited ethylene-vinyl alcohol copolymer film 22 as the barrier layer 20. The vacuum insulation material was manufactured.

<Comparative example 4>
Instead of using the stretched polypropylene film 11 as the base material layer, only the stretched nylon film 12 is used, and as the barrier layer 20, instead of the aluminum-deposited ethylene-vinyl alcohol copolymer film 22, a 7 μm thick aluminum foil is used. A packaging material for a vacuum heat insulating material of Comparative Example 4 was produced in the same manner as in Example 1 except that a 12-μm thick aluminum-deposited polyethylene terephthalate film 21 and an aluminum-deposited polyethylene terephthalate film 21 were used as two barrier layers.

<Comparative Example 5>
Furthermore, in the vacuum insulating material exterior material of Comparative Example 4, instead of the linear low density polyethylene film having a density of 0.935 g / cm ³ or less, the linear low density polyethylene having a density of 0.940 g / cm ^3. A vacuum insulating material exterior material of Comparative Example 5 was produced in the same manner as Comparative Example 4 except that the film was used.

<Test method>
As an evaluation of the bending resistance of the vacuum insulation materials of the examples and the comparative examples, the number of pinholes after being applied to the gelbo flex tester was measured and compared as an index of bending resistance.

<Number of pinholes>
The outer packaging materials of the vacuum heat insulating materials of the example and the comparative example were each cut into 210 mm × 297 mm, and both ends of the 297 mm were bonded together and rounded into a cylindrical shape to prepare a cylindrical test piece.

  Hold both ends of this test piece with the fixed head and drive head of the Gelboflex tester, and while adding a 440 degree twist, narrow the distance between the fixed head and the drive head from 7 inches to 3.5 inches, and add a twist. While maintaining the state, the head interval is reduced to 1 inch, then the head interval is increased to 3.5 inches, and the head interval is increased to 7 inches while returning the twist. The test was performed 300 times at 25 ° C.

Thereafter, a penetrant flaw detection liquid was applied to the test piece and checked to confirm the number of pinholes. Ten test pieces were used, and the average number of pinholes is summarized in Table 1.

以下に、実施例と比較例との比較結果について説明する。

Below, the comparison result of an Example and a comparative example is demonstrated.

<Comparison result>
As shown in Table 1, the vacuum insulation material of Example 1 according to the present invention had almost no pinholes and good bending resistance.

On the other hand, in the vacuum insulation material of the comparative example, the occurrence of pinholes was clearly recognized and the bending resistance was inferior. Moreover, the vacuum insulation material of Example 5 using a linear low-density polyethylene film having a density of 0.940 g / cm ³ for the sealant layer has a linear low density of 0.935 g / cm ³ or less. There were many pinholes and the bending resistance was greatly inferior to the vacuum insulation material of the comparative example 4 using a density polyethylene film.

  As described above, the vacuum insulating material exterior material according to the present invention is excellent in bending resistance and can provide a high-quality vacuum heat insulating material by suppressing pinholes caused by manufacturing breakage. .

  Therefore, the vacuum heat insulating material using the vacuum heat insulating material of the present invention can be applied to any device or facility that needs to be kept cold or warm, such as a refrigerator, a freezer, a water heater, or a vending machine. Is possible. And it can contribute to a significant energy-saving and space-saving by using the exterior material of the vacuum heat insulating material of this invention.

DESCRIPTION OF SYMBOLS 1 ... exterior material 2 ... vacuum heat insulating material 3 ... core material 4 ... heat fusion part 5 ... adhesion part 6 ... flame-retardant tape 10 ... -Base material layer 20 ... Barrier layer 30 ... Sealant layer 11 ... Stretched polypropylene film 12 ... Stretched nylon film 21 ... Aluminum vapor-deposited polyethylene terephthalate film 22 ... Aluminum vapor-deposited ethylene-vinyl alcohol Polymer film

Claims (3)

In order from the outside, a vacuum insulation material consisting of a base material layer, a barrier layer, and a sealant layer,
A stretched polypropylene film and a stretched nylon film were laminated on the base material layer, the stretched polypropylene film was disposed on the outer surface side, and a vapor deposition film of metal or metal oxide was used for the barrier layer. A vacuum insulation exterior material.   The vacuum insulating material exterior material according to claim 1, wherein an aluminum-deposited polyethylene terephthalate film and an aluminum-deposited ethylene-vinyl alcohol copolymer film are laminated on the barrier layer. The exterior material for a vacuum heat insulating material according to claim 1 or 2, wherein a linear low density polyethylene film having a density of 0.935 g / cm ³ or less is used for the sealant layer.

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