JPH04337194A - Vacuum heat insulator and manufacture of vessel of vacuum heat insulator - Google Patents

Abstract

PURPOSE:To improve both gas barrier ability and insulating ability of a vacuum heat insulator and reduce its cost. CONSTITUTION:The plural positions of a metal foil 7 and a protective layer 9 on a forehead part 10c of a vessel 10 for vacuum heat insulator are removed in a belt shape continuously in the circumferential direction. A heat bridge is not formed on the forehead part 10c and a surface heat conduction between the outer edge part 10a etc. and a flat part 10d of the vessel 10 is insulated. As the removal of the metal foil 7 and the protective layer 9 is only applied on the forehead part 10c, a gas barrier ability is maintained. When a film F is molded on the vessel 10 by the heat molding process of a pressed air and vacuum molding, etc., the metal foil 7 and the protective layer 9 are cut off naturally along the plural continuous sewing machine seams. Thereby, the metal foil 7 and the protective layer 9 of the forehead part 10c are removed and the plural non-heat conduction parts 10e are formed automatically. At this time, the stretched amount of the stretched part of a synthetic resin layer 8 is dispersed by the existence of the plural sewing machune seams.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a vacuum insulation material used for example in refrigerators and freezers, and more specifically to a vacuum insulation material and a vacuum insulation material for improving the insulation performance between the inside and outside of the refrigerator. This invention relates to a method for manufacturing a container.

0002

[Prior Art] Generally, for example, in a refrigerator or a freezer,
Insulation between the inside and outside of a refrigerator is an important element for improving refrigeration and freezing capacity. For this reason, in order to improve the heat insulation performance of refrigerators and the like, as shown in FIG. 8, a flat vacuum heat insulating material 2A is attached to the inner surface of the outer box 1 of the refrigerator and the like.

[0003] This vacuum heat insulating material 2A is generally made by molding the container 3 and the container lid 4 from a film having a synthetic resin layer for heat sealing on the inside. Then, the heat insulating spacer material 6 filled in the inner bag 5 is stored in this container 3 and covered with a container lid 4. Next, while vacuuming the inside of the container 3,
It is constructed by heat-sealing synthetic resin layers on the outer edges 3a, 4a of the container 3 and container lid 4. However, in a film having a synthetic resin layer, air, water vapor, etc. permeate and enter, resulting in poor gas barrier properties, a decrease in the degree of vacuum inside the container 3, and a decrease in heat insulation performance.

For this reason, as shown in FIG. 9, a recent vacuum insulation material 2B has a heat-sealing synthetic resin layer 8 on the inside of the metal foil 7, and a metal vapor-deposited synthetic resin layer as a protective layer on the outside. A container 10 and a container lid 11 are formed from a film having a diameter of 9. Then, the heat insulating spacer material 6 filled in the inner bag 5 is stored in this container 10 and covered with a container lid 11. Then,
The interior of the container 10 is evacuated and the synthetic resin layers 8, 8 on the outer edges 10a, 11a of the container 10 and the container lid 11 are heat-sealed. This metal foil 7 is placed in a container 10.
When used over the entire surface of the container 10, the gas barrier property is good, the degree of vacuum inside the container 10 is maintained, and the heat insulation performance is improved.

[0005]

[Problems to be Solved by the Invention] However, the thermal conductivity of the metal foil 7 is much higher than that of synthetic resin or the like. Therefore, a thermal bridge is formed near the forehead 10c of the container 10, and from the outer box 1, the flat part 11b of the container lid 11 → the outer edge 11
a (heat-sealed part) → outer edge 10a of container 10 (heat-sealed part) → peripheral part 10b → forehead part 10c → flat part 1
There was a problem in that heat was conducted to the surface in the order of 0d, and the initial insulation performance deteriorated. Note that the parts that become thermal bridges, especially the outer edge 10a, the peripheral edge 10b, and the frame 10c of the container 10
It is conceivable to remove the metal foil 7 from the base to block heat conduction. However, the metal foil 7 is only on the flat part 10d of the container 10, and the outer edge 10a, the peripheral edge 10b, and the frame 10c.
Since the gas barrier properties of the container 10 deteriorate, the degree of vacuum inside the container 10 decreases, and the heat insulation performance decreases. Moreover, in this case, it is necessary to use getter material to maintain the degree of vacuum inside the container, which increases the cost.

[0006] Accordingly, an object of the present invention is to provide a vacuum heat insulating material and a method for manufacturing a container for a vacuum heat insulating material at low cost, which improve both gas barrier properties and heat insulation performance.

[0007]

[Means for Solving the Problems] In order to achieve the above object, the invention of claim 1 provides a method for forming containers using a film having a synthetic resin layer for heat sealing on the inside of a metal foil and a protective layer on the outside. Vacuum insulation material made by molding a container lid, storing an insulating spacer material in the container, and covering the container with the container lid, creating a vacuum inside the container, and heat-sealing the synthetic resin layer on the outer edge of the container and container lid. The container is characterized in that a plurality of non-heat transfer portions in which the metal foil and the protective layer are successively removed in the circumferential direction are provided on the frame portion of the container located around the heat insulating spacer material.

According to the second aspect of the invention, a container is formed from a film having a synthetic resin layer for heat sealing on the inside of the metal foil and a protective layer on the outside, and a heat insulating spacer material is housed in the container. In the vacuum insulation material, which creates a vacuum inside the container and heat-seals the synthetic resin layer on the outer edge of the container,
In the forehead of the container located around the heat insulating spacer material,
It is characterized by having a plurality of non-heat transfer parts formed by removing the metal foil and the protective layer, spaced apart in the circumferential direction.

[0009] The invention according to claim 3 is also a method for manufacturing a container for vacuum insulation material, which comprises forming a synthetic resin layer for heat sealing on the inside of a metal foil and a protective layer on the outside of the metal foil. The protective layer is made with multiple removable continuous perforations along the area where the forehead is located around the heat insulating spacer material, so that when the film is formed into a container by thermoforming, While the synthetic resin layer on the forehead of the container is being stretched, the metal foil and the protective layer are separated at the perforations, and the metal foil and the protective layer on the forehead of the container are continuous in the circumferential direction at multiple locations. It is characterized in that it can be removed by

0010

[Operation] According to the first aspect of the invention, the metal foil and protective layer on the forehead of the container are continuously removed in the circumferential direction at a plurality of locations. Therefore, a thermal bridge is no longer formed in the frame portion of the container, and surface heat conduction between the outer edge and peripheral portion of the container and the plane portion is blocked, and the initial heat insulation performance can be maintained. In addition, since the metal foil and protective layer are removed only from the frame of the container, gas barrier properties are maintained, the degree of vacuum inside the container is maintained, insulation performance is improved, and getter material is not used. Since there is no need to do so, it is inexpensive.

[0011] According to the second aspect of the invention, the metal foil and the protective layer on the forehead of the container are removed at intervals in the circumferential direction. Therefore, the heat transfer area is reduced and the influence of surface heat conduction is suppressed as much as possible. On the other hand, since the metal foil and protective layer are removed only from the frame of the container, gas barrier properties are maintained, the degree of vacuum inside the container is maintained, insulation performance is improved, and getter material can be used. Since there is no need to do so, it is inexpensive.

According to the third aspect of the invention, when a film is formed into a container by thermoforming such as pressure forming or vacuum forming, the metal foil and the protective layer are naturally separated at continuous perforations, so that the frame part of the container is The metal foil and protective layer are removed. Therefore, the metal foil and the protective layer can be easily and reliably removed from the frame of the container, and the container can be manufactured easily. Furthermore, since the perforations are provided at multiple locations, the amount of elongation of the stretched portion of the heat-sealing synthetic resin layer is dispersed when the container is molded. As a result, the thickness of the synthetic resin layer in the area where the metal foil and protective layer have been removed does not become too thin, making it possible to suppress gas permeation in this area as low as possible, and also prevent a decrease in strength. Furthermore, by adjusting the number of perforations, the width of the removed portion of the metal foil and protective layer can be adjusted.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained in detail below with reference to an embodiment shown in FIGS. 1 to 7. Note that parts having the same configuration and operation as those of the prior art in FIGS. 8 and 9 are given the same numbers and detailed explanations are omitted.

As shown in FIG. 1, the vacuum heat insulating material 2C of this embodiment has a heat-sealing synthetic resin layer 8 on the inside of the metal foil 7, and a metal vapor-deposited synthetic resin 9 as an example of a protective layer on the outside. Container 10 and container lid 11 molded with film F having
It is equipped with This container 10 stores a heat insulating spacer material 6 filled in an inner bag 5 and is covered with a container lid 11. Then, by evacuating the inside of the container 10 and heat-sealing the synthetic resin layers 8, 8 on the outer edges 10a, 11a of the container 10 and the container lid 11, the vacuum insulation material 2
We are manufacturing C.

Of the outer edge portion 10a (heat seal portion), peripheral edge portion 10b, frame portion 10c, and flat portion 10d of the container 10, the metal foil 7 and metal-deposited synthetic resin layer 9 of the frame portion 10c
are continuously removed in the circumferential direction at two locations, and two continuous non-heat transfer portions 10e are formed in the shape of a band on the forehead portion 10c.

With this configuration, no thermal bridge is formed in the frame portion 10c of the container 10 due to the non-heat transfer portion 10e. Therefore, the outer edge 10a and the peripheral edge 10 of the container 10
Heat conduction between b and the flat portion 10d is blocked by the non-heat transfer portion 10e. Furthermore, since the metal foil 7 is removed only from the frame portion 10c of the container 10, gas barrier properties are maintained sufficiently for practical purposes at the outer edge portion 10a, the peripheral edge portion 10b, and the flat portion 10d. The degree of vacuum inside the chamber is maintained, and the insulation performance is also improved.

The non-heat transfer portion 10e of the container 10 can be easily and reliably provided by the following method.

First, as shown in FIG. 2, the laminate film 12 of the metal foil 7 and the metal vapor-deposited synthetic resin layer 9 is coated along the portion where the frame portion 6a of the heat insulating spacer material 6 is located.
Continuous perforations 13 that can be separated are placed in two places in advance. This perforation 13 is, for example, as shown in FIG.
The laminated film 12 can be processed using two rolls R2 and R3 incorporating two rows of blades B in the direction of the rotation axis. Note that the pitch P can be adjusted by changing the rotational speed of the rolls R2 and R3.

After forming the perforations 13 by the above method,
A synthetic resin layer 8 for heat sealing is laminated on the inside of this laminate film 12 to produce a film F.

Next, as shown in FIG. 4, this film F is set on a pressure/vacuum forming mold 15 with the outer metal vapor-deposited synthetic resin layer 9 facing the recess 15a. After that, the exhaust holes 15b, ... 15b of the recess 15a of the mold 15 are
When the air is evacuated, the film F is dented along the recess 15a of the mold 15, and the container 10 is molded, as shown in FIG.

When this container 10 is molded, the perforations 13 of the laminate film 12 consisting of the metal foil 7 and the metal-deposited synthetic resin layer 9 are naturally formed while the synthetic resin layer 8 of the frame portion 10c of the container 10 is being stretched. Since the container 10 is separated, the metal foil 7 and the metal-deposited synthetic resin layer 9 are removed from the frame portion 10c of the container 10, and a non-heat transfer portion 10e is automatically formed.

Furthermore, since the perforations 13 are provided at two locations, the amount of elongation of the stretched portion of the synthetic resin layer 8 is more dispersed than when the perforations are provided at only one location (see FIG. 6). Therefore, the thickness t2 (see FIG. 7) of the synthetic resin layer 8 at the part where the metal foil 7 and the metal vapor-deposited synthetic resin layer 9 are removed is the thickness of the synthetic resin layer 8 when there is only one perforation. It becomes larger than t1. In this way, metal foil 7
Since the thickness of the synthetic resin layer 8 in the portion where the metal vapor-deposited synthetic resin layer 9 has been removed, that is, the non-heat transfer portion 10e, does not decrease much, gas permeation can be suppressed as low as possible, and a decrease in strength can also be prevented. . Note that the width of the non-heat transfer portion 10e can be adjusted by adjusting the number of perforations.

Next, a second embodiment will be explained using FIGS. 10 to 12. FIG. 10 is an enlarged sectional view of a main part of the vacuum heat insulating material 2D of this embodiment, and FIG. 11 is a plan view of this vacuum heat insulating material. As shown in Figure 10, this vacuum insulation material 2D
The container 20 consists of two container parts 21, 21 of the same shape. Each container portion 21 is formed of a film F having a heat-sealing synthetic resin layer 28 on the inside of a metal foil 27 and a metal vapor-deposited synthetic resin layer 29 as an example of a protective layer on the outside. After the vacuum insulation material 2D stores the insulation spacer material 6 filled in the inner bag 5 in the container 20,
The outer edges 20 of both container parts 21 are vacuumed to a predetermined level inside.
It is manufactured by heat-sealing the synthetic resin layers 28, 28 of a and 20a.

Among the outer edge portion 20a (heat-sealed portion), peripheral edge portion 20b, frame portion 20c, and flat portion 20d of the container 20, the metal foil 27 and metal-deposited synthetic resin layer 29 of the frame portion 20c are shown in FIG. , they are removed at regular intervals in the circumferential direction, thereby forming countless non-heat transfer parts 20e in the forehead part 20c.

[0025] With this configuration, the heat transfer area is greatly reduced, so that the influence of surface heat conduction due to the metal foil is suppressed as much as possible. On the other hand, since the metal foil 20 and the metal vapor-deposited synthetic resin layer 29 are removed only from the frame portion 20c of the container 20, the gas barrier properties are practically sufficient at the outer edge portion 20a, the peripheral edge portion 20b, and the flat portion 20d. container 20
The degree of vacuum inside is maintained. As a result, changes in initial heat insulation performance over time are suppressed to the utmost.

By the way, the non-heat transfer portion 20e is shown in FIG.
It can be formed by the method shown in 2. This is a method similar to the method of forming perforations shown in FIG. 3, but in the case of this embodiment, instead of the blade B shown in FIG. R2 and R3, and is formed by punching a circular hole 33 in the laminate film 32 of the metal foil 27 and the metal-deposited synthetic resin layer 29.

[0027]

Effects of the Invention As is clear from the above description, the vacuum insulation material of claim 1 is obtained by removing the metal foil and protective layer from the forehead of the container continuously in the circumferential direction at a plurality of locations.
A thermal bridge is no longer formed in this forehead area. This blocks surface heat conduction between the outer edge and peripheral edge of the container and the flat surface, so that the initial heat insulation performance can be maintained. Further, since the metal foil and protective layer are removed only from the frame portion of the container, the gas barrier properties are maintained, the degree of vacuum inside the container is maintained, and the heat insulation performance is improved. Furthermore, this eliminates the need for a getter material, thereby reducing costs.

[0028] Furthermore, in the vacuum insulation material of claim 2, the metal foil and protective layer on the forehead of the container are removed at a plurality of locations at intervals in the circumferential direction, so that the heat transfer area is significantly reduced. Ru. Thereby, the influence of surface heat conduction can be suppressed as much as possible, and an initial decrease in insulation performance can be prevented. Furthermore, since the metal foil and protective layer are removed only from the frame of the container, gas barrier properties are maintained, the degree of vacuum inside the container is maintained, and the heat insulation performance is improved. Furthermore, since no getter material is required, costs can be reduced.

[0029] Furthermore, in the method of manufacturing a container for vacuum insulation material according to claim 3, by making perforations in advance in the metal foil and the protective layer so that the film can be separated, when forming the film into the container, the frame portion of the container can be easily removed. The metal foil and protective layer are automatically removed. As a result, the metal foil and the protective layer can be easily and quickly removed from the frame of the container without using a complicated and expensive etching process, so the container can be manufactured easily and at low cost. Furthermore, since perforations are provided at multiple locations, the amount of elongation of the synthetic resin layer for heat sealing is dispersed during molding of the container. Thereby, it is possible to prevent the thickness of the synthetic resin layer from being significantly reduced in the portion where the metal foil and the protective layer are removed, and therefore, it is possible to prevent gas permeation and a decrease in strength as much as possible.

[Brief explanation of the drawing]

[Fig. 1] Cross-sectional view of essential parts of a vacuum heat insulating material according to an embodiment of the present invention

[Figure 2] Plan view of a laminate film of metal foil and protective layer

[Figure 3] Diagram explaining how to make perforations in laminated film

[Figure 4] Cross-sectional view of the mold with the film set

[Figure 5
] Cross-sectional view of the mold used to form the container

[Figure 6] Cross-sectional view of the main part of the container when there is only one perforation

[Figure 7] Cross-sectional view of the main part of the container when perforations are made in two places

[Figure 8] Cross-sectional view of conventional vacuum insulation material

[Figure 9] Cross-sectional view of main parts of conventional vacuum insulation material

FIG. 10: A sectional view of essential parts of a vacuum insulation material according to another embodiment of the present invention.

[Figure 11] Plan view of the vacuum insulation material in Figure 10

[Figure 12]
Diagram explaining how to make holes in laminated film

[Explanation of symbols]

2A, 2B, 2C, 2D... Vacuum heat insulating material, 6... Heat insulating spacer material, 6a... Forehead, 7, 27... Metal foil, 8, 28... Synthetic resin layer for heat sealing, 9, 29... Protective layer, 10 ,2
0... Container, 10a, 11a, 20a... Outer edge, 10b,
20b...Peripheral part, 10c, 20c...Forehead part, 10d, 20
d...Plane part, 10e, 20e...Non-heat transfer part, 11...Container lid, 13...Perforation, 15...Mold for compressed air/vacuum forming, 21
...Container part, 33...hole, F...film.

Claims (3)

[Claims] Claim 1: A container and a container lid are formed from a film that has a synthetic resin layer for heat sealing on the inside of metal foil and a protective layer on the outside, and a heat insulating spacer material is stored in this container, and the container lid is In the vacuum insulation material, which is made by putting a lid on the container, evacuating the inside of the container, and heat-sealing the synthetic resin layer on the outer edge of the container and the container lid, a metal foil is placed on the frame of the container located around the insulation spacer material. A vacuum heat insulating material characterized by having a plurality of non-heat transfer parts formed by continuously removing the protective layer in the circumferential direction. 2. A container is formed from a film that has a synthetic resin layer for heat sealing on the inside of metal foil and a protective layer on the outside, and a heat insulating spacer material is housed in this container, and the inside of the container is vacuumed. At the same time, in the vacuum insulation material made by heat-sealing the synthetic resin layer on the outer edge of the container, there is a non-heat-transfer part formed by removing the metal foil and the protective layer on the forehead of the container located around the insulation spacer material. A vacuum insulation material characterized by having a plurality of spaced apart spaces in the circumferential direction. 3. A synthetic resin layer for heat sealing is provided on the inside of the metal foil, and a protective layer is provided on the outside of the film, and the metal foil and the protective layer are provided with a heat-sealing synthetic resin layer along the area around the heat insulating spacer material where the forehead is located. When the film is formed into a container by thermoforming with multiple separable continuous perforations in advance, the metal foil and the protective layer are separated at the perforations, and the metal foil on the frame of the container and the protective layer are continuously removed in the circumferential direction at multiple locations. Method.