JP2019184020A - Vacuum heat insulation material - Google Patents

Abstract

To provide a vacuum heat insulation material making it possible to carry out molding in a three-dimensional shape having sufficient heat insulation performance even if it is a thin type.SOLUTION: A vacuum heat insulation material 2 includes a core member 30 and an outer packaging 40 obtained by subjecting the core member 30 to decompression sealing. The core member includes an inner layer 10 and an outer layer 20. The inner layer is composed of an inorganic fiber sheet 4 or a laminate sheet in which the inorganic fiber sheet 4 and resin fiber sheets 6a and 6b are alternately disposed. The outer layer is composed of the resin fiber sheets 6 and 6b disposed so as to be in contact with an upper surface 10a and a lower surface 10b of the inner layer 10.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vacuum heat insulating material in which a core member is sealed under reduced pressure with an outer packaging material.

  A vacuum heat insulating material is widely used in which a core member is sealed under reduced pressure with an outer packaging material to improve heat insulating performance. Depending on the installation location of the vacuum heat insulating material, it may be desired to bend the vacuum heat insulating material. In order to cope with this, a vacuum heat insulating material including a core material portion in which non-stretchable portions and stretchable portions are alternately arranged and an outer packet portion that wraps the core material portion has been proposed (for example, see Patent Document 1). .

JP 2006-176491 A

  Since the vacuum heat insulating material described in Patent Document 1 has a structure in which a core material mainly composed of glass wool is sealed with an outer packaging material, the core material cannot be made too thin in consideration of a decrease in heat insulating properties. . Therefore, although it can be bent in a predetermined direction depending on the shape and arrangement of the non-expandable portion and the expandable portion of the core member, it is difficult to bend in other directions. Therefore, it cannot be molded into a desired three-dimensional shape.

  Accordingly, an object of the present invention is to solve the above-described problems, and to provide a vacuum heat insulating material capable of forming a three-dimensional shape having sufficient heat insulating performance even if it is thin.

The vacuum heat insulating material of the present invention is
An inner layer composed of an inorganic fiber sheet or a laminated sheet in which inorganic fiber sheets and resin fiber sheets are alternately disposed, and an outer layer composed of a resin fiber sheet disposed so as to contact the upper surface and the lower surface of the inner layer A core member having
An outer packaging material in which the core member is sealed under reduced pressure;
It is characterized by providing.

  In the present invention, since the inorganic fiber sheet and the resin fiber sheet are in contact with each other, a plurality of minute air layers are present at the boundary portion, and thereby sufficient heat insulation performance is provided even if the layer is thin. In addition, by heating and thermally deforming the resin fiber sheet disposed in the outermost layer of the core member, it becomes possible to mold into various three-dimensional shapes. At this time, a difference in thermal expansion occurs between the inorganic fiber sheet and the resin fiber sheet due to heating, but the contact portions are limited because the fiber sheets are in contact with each other, and there are a plurality of minute air layers in the boundary portion. Therefore, damage due to a difference in thermal expansion can be suppressed.

  As described above, the present invention can provide a vacuum heat insulating material capable of forming a three-dimensional shape having sufficient heat insulating performance even if it is thin.

  The present invention is characterized in that the resin fiber sheet has a hardness lower than that of the inorganic fiber sheet.

  In the present invention, since the hardness of the resin fiber sheet is lower than the hardness of the inorganic fiber sheet, the resin fiber sheet is deformed more greatly during vacuum drawing at the time of manufacturing the vacuum heat insulating material, and a large number of minute air layers are generated. Thereby, while having the outstanding heat insulation performance, the damage by a thermal expansion difference can be suppressed effectively.

The present invention also provides
The resin fiber sheet is formed of olefinic short fibers.

  In the present invention, since the resin fiber sheet is formed of olefinic short fibers, a lightweight and highly reliable vacuum heat insulating material that can be easily molded into a three-dimensional shape can be realized. Furthermore, in the case of low temperature, since the heat conductivity of the resin fiber sheet which consists of an olefin type short fiber falls, heat insulation performance improves more. Therefore, this vacuum heat insulating material can be particularly suitably used for refrigerators, freezers, cold containers, and the like.

The present invention also provides
The fibers of the resin fiber sheet and the inorganic fiber sheet are oriented in substantially the same direction substantially orthogonal to the thickness direction of the sheet.

  In the present invention, since the fibers of the resin fiber sheet and the inorganic fiber sheet are oriented in a direction substantially orthogonal to the thickness direction of the sheet, a so-called heat bridge is generated, which is a thermal short circuit caused by the fibers extending in the thickness direction. Therefore, excellent heat insulation performance can be obtained. Furthermore, since the fibers of the resin fiber sheet and the inorganic fiber sheet are oriented in substantially the same direction, even when a thermal expansion difference occurs, the friction between the fibers of the resin fiber sheet and the inorganic fiber sheet is further reduced and damaged. Can be effectively suppressed.

The present invention also provides
The core member is disposed inside a joint portion of the outer packaging material.

  In the present invention, since the core member can be thinned, the core member can be put in an envelope-shaped outer packaging material and evacuated. As a result, it is possible to realize a vacuum heat insulating material in which the core member is arranged inside the joint portion of the outer packaging material without having the ear portion, so that the ear processing of the outer packaging material becomes unnecessary and the manufacturing process can be simplified. it can.

  As described above, in the present invention, it is possible to provide a vacuum heat insulating material that has sufficient heat insulating performance even in a thin shape and can be molded into a three-dimensional shape.

It is side surface sectional drawing which shows typically the vacuum heat insulating material which concerns on the 1st Embodiment of this invention. It is side surface sectional drawing which shows typically the boundary area | region of an inorganic fiber sheet and a resin fiber sheet. It is side surface sectional drawing which shows typically the vacuum heat insulating material which concerns on the 2nd Embodiment of this invention. It is a perspective view which shows typically the case where a thick core member is put into the outer packaging material which has an ear | edge part. It is a perspective view which shows typically the case where a thin core member is put into an envelope-shaped outer packaging material. It is a figure (photograph) which shows the Example which provided the recessed part by the bending process in the vacuum heat insulating material actually manufactured. It is a figure (photograph) which shows the Example which shape | molded the three-dimensional shape to the vacuum heat insulating material which was actually manufactured.

Embodiments for carrying out the present invention will be described below with reference to the drawings. The embodiment described below is for embodying the technical idea of the present invention, and the present invention is not limited to the following unless otherwise specified.
In each drawing, members having the same function may be denoted by the same reference numerals. In view of ease of explanation of the main points or ease of understanding, the embodiments may be shown separately for convenience, but partial replacement or combination of configurations shown in different embodiments is possible. In the embodiment described later, description of matters common to the above-described embodiment is omitted, and only different points will be described. In particular, the same operational effects by the same configuration will not be sequentially described for each embodiment. The size, positional relationship, and the like of the members shown in each drawing may be exaggerated for clarity of explanation.

(Vacuum insulation material according to the first embodiment of the present invention)
FIG. 1 is a side sectional view schematically showing the vacuum heat insulating material 2 according to the first embodiment of the present invention.

Referring to FIG. 1, the vacuum heat insulating material 2 according to the first embodiment of the present invention is configured such that a core member 30 that functions as a heat insulating material is sealed under reduced pressure by an outer packaging material 40. The outer packaging material 40 is a film including a resin layer.
The core member 30 includes an inner layer 10 composed of the inorganic fiber sheet 4 and an outer layer 20 composed of the resin fiber sheets 6a and 6b disposed so as to be in contact with the upper surface 10a and the lower surface 10b of the inner layer 10. . There is no adhesive layer between the laminated inorganic fiber sheet 4 and resin fiber sheets 6a and 6b, and they are in close contact with each other under reduced pressure.

<Inorganic fiber sheet>
In this embodiment, glass wool is used as the material of the inorganic fiber sheet 4, and a wet type is particularly preferable. Regarding the fiber diameter of glass wool, when the fiber diameter is thin, the space between the fibers increases and the porosity increases, so that the thermal conductivity can be reduced and the fiber weight variation can be reduced. On the other hand, when the fiber diameter is reduced, the entanglement between the fibers is weakened and the strength is lowered. Considering these comprehensively, the fiber diameter of glass wool is preferably about 1 μm to 8 μm, and more preferably about 3 μm to 5 μm.

Regarding the fiber length of glass wool, if the fiber length is short, the fiber weight variation can be reduced. On the other hand, if the fiber length of glass wool is short, the fibers are less entangled and the strength is lowered. Considering these comprehensively, the fiber length of glass wool is preferably about 2 to 100 mm, more preferably about 3 mm to 50 mm.
If the fiber length is short, the fiber is oriented in the heat insulation direction and the heat insulation performance may be reduced by so-called heat bridge. In this embodiment, measures to avoid this are taken as described later.

  The material of the inorganic fiber sheet 4 is not limited to the case of using glass wool, and inorganic fibers such as glass fiber, alumina fiber, silica alumina fiber, silica fiber, rock wool, and silicon carbide fiber can also be used.

<Resin fiber sheet>
The resin fiber is usually formed from a thermoplastic resin. Among such thermoplastic resins, in this embodiment, an olefin resin typified by polypropylene or polyethylene is used. In particular, olefinic short fibers having a relatively short fiber length are preferred. Among these, it is more preferable to use a nonwoven fabric made of polypropylene by a melt blow method.

  As for the resin fiber, if the fiber diameter is small, the space between the fibers increases and the porosity increases, so that the thermal conductivity can be reduced and the basis weight variation of the fibers can be reduced. On the other hand, when the fiber diameter is reduced, the entanglement between the fibers is weakened and the strength is lowered. Considering these comprehensively, the fiber diameter of the resin fiber is preferably about 1 μm to 8 μm, more preferably about 3 μm to 5 μm.

Regarding the fiber length of the resin fiber, if the fiber length is short, variation in the basis weight of the fiber can be reduced. On the other hand, when the fiber length of the resin fiber is short, there is little entanglement between the fibers and the strength is lowered. Considering these comprehensively, the fiber length of the resin fiber is preferably about 2 to 100 mm, more preferably about 3 mm to 50 mm.
If the fiber length is short, the fiber is oriented in the heat insulation direction and the heat insulation performance may be reduced by so-called heat bridge. In this embodiment, measures to avoid this are taken as described later.

  The material of the resin fiber sheet 6 is not limited to the case of using olefin-based resin fibers, and any other thermoplastic resin fibers such as nylon, polyester resin, acrylic, vinylon, and polyurethane can be used.

<Outer packaging material>
As the outer packaging material 40 according to this embodiment, a gas barrier film having a four-layer structure as shown below is used. In order from the outermost layer to the innermost layer, nylon, polyethylene terephthalate resin, or the like that functions as a surface protective layer is disposed in the outermost layer. Next, aluminum vapor deposition PET (polyethylene terephthalate) functioning as a gas barrier layer is disposed as the first intermediate layer. Next, an aluminum foil is disposed as the second intermediate layer. And the high density polyethylene which functions as a seal layer is arrange | positioned as an innermost layer.

The outer packaging material 40 is not limited to the case where the above-described four-layer gas barrier film is used. For example, a three-layer gas barrier film made of polyethylene terephthalate resin, aluminum foil, and high-density polyethylene resin, polyethylene terephthalate resin, aluminum vapor deposition layer It is also possible to use an ethylene-vinyl alcohol copolymer resin having a gas barrier film made of a high-density polyethylene resin or the like.
Examples of the thickness of the outer packaging material 40 include 15 μm to 200 μm.

<Insulation performance>
In the vacuum heat insulating material, since the core member is sealed in a state where the pressure is reduced in the outer packaging material, the influence of the convective heat transfer by the air in the outer packaging material is very small, and the heat conduction in the core member is the vacuum heat insulating material. It has a great influence on the heat insulation performance.

  FIG. 2 is a side sectional view schematically showing a boundary region between the inorganic fiber sheet 4 and the resin fiber sheet 6. As shown in FIG. 2, in the vacuum heat insulating material 2 according to this embodiment, the inorganic fiber sheet 4 and the resin fiber sheet 6 are in contact with each other at the boundary between the inner layer 10 and the outer layer 20 of the core member 30. As shown, there are a plurality of minute air layers. Since the air layer has high heat insulating properties, the vacuum heat insulating material 2 according to the present embodiment can have sufficient heat insulating performance even if it is thin.

<Heat deformation performance>
Since the outer packaging material is a film having a resin layer as described above, it expands due to thermal expansion when heated. If the core member does not have an outer layer made of a resin fiber sheet, and the core member made of inorganic fibers and the outer packaging material are in direct contact with each other, if the vacuum heat insulating material is heated to thermally deform, Although the material expands due to thermal expansion, the core member made of inorganic fibers does not expand so much, so a difference in thermal expansion occurs at the boundary between the core member and the outer packaging material.
At this time, since the outer packaging material including the resin film is in close contact with the outer surface of the core member due to the reduced pressure, a large frictional force is generated between the outer packaging material and the core member, and damage may occur at the boundary portion.

On the other hand, in the present embodiment, the outer layer 20 composed of the resin fiber sheets 6 a and 6 b exists between the inner layer 10 composed of the inorganic fiber sheet 4 and the outer packaging material 40. If the vacuum heat insulating material 2 is heated to be thermally deformed, the outer layer 20 that is the resin fiber sheet 6 thermally expands following the outer packaging material 40 including the resin film. On the other hand, at the boundary between the inner layer 10 and the outer layer 20 of the core member 30, the inner layer 10 that is the inorganic fiber sheet 4 does not thermally expand as compared with the outer layer 20, and the boundary between the inner layer 10 and the outer layer 20. There is a difference in thermal expansion at the part.
However, since the inorganic fiber sheet 4 and the resin fiber sheet 6 are in contact with each other at the boundary portion between the inner layer 10 and the outer layer 20, the contact portion is limited, and a plurality of minute air layers are further formed at the boundary portion. Since it exists, the frictional force is small, and it can slide against each other to suppress damage due to thermal expansion difference. As described above, since there is no adhesive layer at the boundary between the inner layer 10 and the outer layer 20, slippage between the fiber sheets is not constrained.

Accordingly, by heating the vacuum heat insulating material 2 according to the present embodiment and thermally deforming the resin fiber sheets 6a and 6b arranged in the outermost layer of the core member 30, molding into various three-dimensional shapes becomes possible. .
As described above, in the present embodiment, it is possible to provide the vacuum heat insulating material 2 capable of forming a three-dimensional shape having sufficient heat insulating performance even if it is thin. Thereby, the design-free vacuum heat insulating material 2 is realizable, and it leads to the market expansion of a vacuum heat insulating material.

  Furthermore, the hardness of the resin fiber sheet 6 is preferably lower than the hardness of the inorganic fiber sheet 4. When the hardness of the resin fiber sheet 6 is lower than the hardness of the inorganic fiber sheet 4, when the core member 30 is put in the outer packaging material 40 and evacuated, the inorganic fiber sheet 4 does not deform so much, but the resin fiber sheet 6 deforms more than that. For this reason, a lot of minute spaces are generated between the inorganic fiber sheet 4 and the resin fiber sheet 6 (see arrow A in FIG. 2), and thus a lot of minute air layers can be formed. Since this air layer acts as a heat insulating layer, the vacuum heat insulating material 2 can have excellent heat insulating performance even if it is thin. Moreover, since the contact portion is more limited by the air layer at the boundary between the inner layer 10 and the outer layer 20, damage due to a difference in thermal expansion between the inorganic fiber sheet 4 and the resin fiber sheet 6 is effectively prevented. Can be suppressed.

As shown in FIG. 2, in this embodiment, the fiber f6 of the resin fiber sheet 6 and the fiber f4 of the inorganic fiber sheet 4 are oriented in a direction substantially perpendicular to the thickness direction of the sheet. Thereby, even if the length of the fiber is short, the occurrence of a so-called heat bridge, which is a thermal short circuit caused by the fiber extending in the thickness direction, can be suppressed, and thus excellent heat insulating performance can be obtained.
Furthermore, since the fiber f6 of the resin fiber sheet 6 and the fiber f4 of the inorganic fiber sheet 4 are oriented in substantially the same direction, even when a difference in thermal expansion occurs, it becomes easier to slip in the fiber longitudinal direction, and the inner layer 10 and The frictional force generated at the boundary with the outer layer 20 is further reduced, and damage can be more effectively suppressed.

  However, the present invention is not limited to this, and the fibers f6 and f4 of the resin fiber sheet 6 and the inorganic fiber sheet 4 are oriented in a direction substantially orthogonal to the thickness direction of the sheet. The fibers f6 and f4 of the fiber sheet 6 and the inorganic fiber sheet 4 may be arranged at a predetermined angle. Further, the fibers f6 and f4 of the resin fiber sheet 6 and the inorganic fiber sheet 4 are oriented in a direction substantially orthogonal to the thickness direction of the sheet, but the fibers f6 of the resin fiber sheet 6 and the inorganic fiber sheet 4 in plan view. , F4 may be arranged in a random direction. In these cases, it can be expected that more air layers are provided between the resin fiber sheet 6 and the inorganic fiber sheet 4.

  As described above, in the present embodiment, the resin fiber sheet 6 is formed from olefinic short fibers. Olefin-based resins are excellent in heat resistance, cold resistance, and weather resistance, and are lightweight and can be recycled, so that manufacturing costs can be reduced. As a result, a lightweight and reliable vacuum heat insulating material that can be easily molded into a three-dimensional shape can be realized.

  Furthermore, it should be noted that, at low temperatures, the thermal conductivity of the resin fiber sheet 6 made of olefinic short fibers is lowered and the heat insulation performance is further increased. Therefore, the vacuum heat insulating material 2 which concerns on this embodiment is especially suitable for using for a refrigerator, a freezer, a cold storage container, etc.

(Vacuum insulation material according to the second embodiment of the present invention)
FIG. 3 is a side sectional view schematically showing the vacuum heat insulating material 2 according to the second embodiment of the present invention.
In said 1st Embodiment, although the inner layer 10 was comprised from the one inorganic fiber sheet 4, in this embodiment, the inner layer 10 is the inorganic fiber sheet 4a, the resin fiber sheet 6c, from the drawing upper side, The difference is that it is composed of three-layer laminated sheets 8 arranged alternately in the order of the inorganic fiber sheets 4b. Similarly to the first embodiment, the resin fiber sheets 6a and 6b are in contact with the upper and lower surfaces 10a and 10b of the inner layer 10, respectively. There is no adhesive layer between the laminated inorganic fiber sheets 4a and 4b and the resin fiber sheets 6a, 6b and 6c, and they are in close contact with each other due to reduced pressure.

Thus, when the inner layer 10 is comprised from the lamination sheet 8 by which the inorganic fiber sheet 4a, the resin fiber sheet 6c, and the inorganic fiber sheet 4b are arrange | positioned alternately, inorganic fiber sheet 4a, b and resin fiber sheet are comprised. Since a plurality of minute air layers are also formed between 6c, the heat insulation performance is further enhanced.
Further, at the boundary between the inorganic fiber sheets 4a and 4b and the resin fiber sheet 6c in the inner layer 10, the contact portions are limited because the fiber sheets are in contact with each other, and a plurality of minute air layers are further formed at the boundary portions. Therefore, damage due to a difference in thermal expansion can be suppressed.
Further, when the inner layer 10 is composed of the laminated sheet 8, in addition to the resin fiber sheets 6a and 6b constituting the outer layer 20, the resin fiber sheet 6c constituting the laminated sheet 8 of the inner layer 10 is thermally deformed. By doing so, the strength of the three-dimensional shape can be increased.

In this embodiment, the inorganic fiber sheets 4a and 4b and the resin fiber sheet 6c are composed of the three-layered laminated sheet 8 alternately arranged. However, the present invention is not limited to this, and an arbitrary number of inorganic fiber sheets. And the lamination sheet of arbitrary lamination | stacking numbers which laminated | stacked the resin fiber sheet alternately can be employ | adopted. Moreover, the outermost layer of the inner layer 10 in contact with the resin fiber sheets 6a and 6b constituting the outer layer 20 is not necessarily an inorganic fiber sheet, and may be a resin fiber sheet. That is, the resin fiber sheets may be in contact with each other at the boundary between the inner layer 10 and the outer layer 20.
Since other points are the same as those in the first embodiment, further description is omitted.

In the vacuum heat insulating material 2 which concerns on said 1st and 2nd embodiment, the following can be illustrated as a dimension of each member before decompressing. The thickness of the inner layer 10 can be about 1 mm to 8 mm, and the thickness of the outer layer 20 (the total thickness of the upper and lower resin fiber sheets 6) can be about 2 mm to 5 mm. Therefore, the thickness dimension of the core member 30 is about 3 mm to 20 mm. Since the thickness of the outer packaging material 40 is 200 μm or less, the thickness dimension of the vacuum heat insulating material 2 in which the core member 30 is sealed under reduced pressure in the outer packaging material 40 is about 1 mm to 15 mm.
Thus, since the vacuum heat insulating material 2 which concerns on this embodiment is very thin, it can be thermally deformed to a desired shape according to a use so that it may mention later.

(Method for manufacturing vacuum insulation)
In a general manufacturing method of vacuum heat insulating material, a sheet formed from a film having gas shielding properties is prepared, and three sides of the sheet are heat-sealed leaving an opening to form a bag-shaped outer packaging material To do. Then, the core member is put into the outer packaging material from the opening and evacuated, and the opening portion is heat-sealed to seal the core member under reduced pressure with the outer packaging material.

  FIG. 4 is a perspective view schematically showing a case where the thick core member 130 is put into the outer packaging material 140 having the ear part B as shown by the arrow B. FIG. FIG. 5 is a perspective view schematically showing a case where the thin core member 30 is put in the envelope-shaped outer packaging material 40.

  As shown in FIG. 4, in order to obtain heat insulation performance, the core member 130 of the conventional vacuum heat insulating material 102 has a predetermined thickness. For this reason, in order to secure a space in which the core member 130 can be inserted, it is necessary to use the outer packaging material 140 having the ear portion B having a predetermined size in which three sides except for one side serving as the opening are heat-sealed. In this case, when vacuuming is performed and the opening is heat-sealed, the ear B where the core member 130 is not packed becomes an excessive portion. For this reason, when the vacuum heat insulating material 102 is installed in the heat insulating portion, an ear folding operation of the ear portion B occurs, and the outer packaging material 140 may be damaged during the ear folding operation.

  On the other hand, as shown in FIG. 5, in the vacuum heat insulating material 2 which concerns on embodiment of this invention, since the core member 30 is thin, the envelope-shaped outer packaging material 40 which does not have an ear | edge part can be used. That is, a sheet having gas shielding properties is folded, and two sides except for one side that becomes an opening are fastened by heat welding as shown by an arrow C in FIG. 5 (the remaining one side becomes a bent portion), and an envelope A shaped outer packaging material 40 is formed. And the vacuum heat insulating material 2 can be manufactured by putting the core member 30 into the envelope-shaped outer packaging material 40 from an opening, evacuating, and thermally welding an opening part. In this case, the ear portion does not occur, and there are no problems such as the ear folding work and the damage that occurs during the ear folding work.

As mentioned above, in the vacuum heat insulating material 2 which concerns on embodiment of this invention, since the core member 30 can be made thin, the core member 30 can be sealed in the envelope-shaped outer packaging material 40. FIG. That is, in the vacuum heat insulating material 2 according to the present embodiment, the core member 30 is disposed inside the joint portion C of the outer packaging material 40. Therefore, the ear part does not occur, and problems such as the ear folding work and the damage that occurs during the ear folding work do not occur.
However, also in the vacuum heat insulating material 2 which concerns on embodiment of this invention, the outer packaging material 140 which has the ear | edge part B by which 3 sides were heat-sealed can also be used. In this case, since the core member can be made thin, the width of the ear portion can be reduced.

(Other embodiments)
In the vacuum heat insulating material 2 according to the first and second embodiments, the two resin fiber sheets 6a and 6b that are in contact with the upper and lower surfaces 10a and 10b of the inner layer 10 are disposed. However, not only when the different sheets 6a and 6b are arranged above and below the inner layer 10, but using a single sheet, the upper and lower surfaces and side surfaces of the inner layer 10 may be covered with one sheet. . In that case, there may be a case where only one side surface is covered with one sheet, or a case where both side surfaces are covered (that is, the entire inner layer 10 is covered).

  In the vacuum heat insulating material 2 which concerns on embodiment of this invention, since it can shape | mold into a desired shape according to an installation place, for example, when using the vacuum heat insulating material 2 for the heat insulation in the store | warehouse | chamber of a refrigerator, the volumetric efficiency in a store | warehouse | chamber is Can be increased. In particular, when the vacuum heat insulating material 2 is installed in the vicinity of the evaporator of the refrigerator, the vacuum heat insulating material 2 is molded in advance according to the uneven shape by ribs or the like, thereby increasing the volumetric efficiency and the work efficiency of installing the vacuum heat insulating material 2 And the risk of breakage during work can be reduced.

  The vacuum heat insulating material 2 according to the above embodiment is not only applied to a refrigerator, but also includes a cold insulation box, a construction panel, a cold container for a medical device, a vending machine, a showcase, a heat insulation helmet, a thermal lunch box, and a water heater. It can be suitably applied to various devices such as the beginning.

Next, a description will be given of tests actually performed by manufacturing the vacuum heat insulating material according to the second embodiment.
The specifications of the manufactured vacuum insulation are as follows.
(1) Core member (a) Inner layer: Three-layer laminated sheet arranged alternately in the order of inorganic fiber sheet, resin fiber sheet, and inorganic fiber sheet (b) Outer layer: so as to contact the upper and lower surfaces of the inner layer Arranged resin fiber sheet (c) Inorganic fiber sheet: Glass wool
Manufacturer_Changzhou Changhaisha
Part No._S-VIP120
Average thickness 1.09mm 120g / m2
(C) Resin fiber sheet: Olefin
Manufacturer_Japan Vilene
Part No._OF-13042 (T-1Z)
Average thickness 1.5mm 75g / m2
(2) Outer packaging material Film configuration
Manufacturer_J film
Specification_ONY15μ / VMPET12μ / AL7μ / LLDPE50μ

(Test 1)
First, based on JIS A 1412-1, the thermal conductivity of the vacuum heat insulating material was measured. At this time, it measured using 2 specimens (No. 1 and No. 2).
(1) Test piece specifications (a) Dimensions (No. 1) 305 mm x 317 mm, thickness 4.7 mm
(No. 2) 304 mm × 302 mm, thickness 4.8 mm
(B) Weight (No. 1) 97.90 g
(No. 2) 97.28 g

[Test results]

As described above, in the vacuum heat insulating material according to this example, the heat conductivity when the average temperature θ _m is 0 ° C. is 0.0054 W / (m · K), and the heat when the average temperature θ _m is 23 ° C. The conductivity is 0.0067 W / (m · K). Therefore, it was demonstrated that the vacuum insulation material has a high heat insulation performance despite the fact that the average thickness of the vacuum insulation material is very thin at 4.75 mm. It was also demonstrated that when the average temperature θ _m is 0 ° C., the heat insulation performance is improved by 24% compared to when the average temperature θ _m is 23 ° C. That is, it was proved that the heat insulation performance of the vacuum heat insulating material has temperature heterogeneity, and that the lower the temperature, the higher heat insulation performance can be obtained.

(Test 2)
Next, the improvement rate of the heat insulation performance at the time of adding the vacuum heat insulating material which concerns on a present Example with respect to the cooler box using the conventional vacuum heat insulating material or a urethane foam material was measured.

[Test results]

  As described above, it has been proved that the heat insulating performance is improved by 14% by adding the vacuum heat insulating material according to the above embodiment to the cooler box provided with the conventional vacuum heat insulating material. In addition, even in a cooler box having a urethane material that is thick but has high heat insulation performance, it was proved that the heat insulation performance was improved by 7% by adding the vacuum heat insulation material according to the above-described example. In any case, the improvement of the heat insulation performance by the vacuum heat insulating material according to the above-described example was proved.

(Test 3)
Next, the test which performs a bending process and three-dimensional shaping | molding was performed to the vacuum heat insulating material actually manufactured. FIG. 6 is a diagram (photograph) showing an embodiment in which a concave portion is provided by bending in an actually manufactured vacuum heat insulating material. FIG. 7 is a diagram (photograph) showing an example in which a three-dimensional shape was formed on a vacuum heat insulating material actually manufactured.

  As shown in FIG. 6, a recess is provided in the central portion of the vacuum heat insulating material without wrinkling. 7A is a perspective view of a molded product obtained by molding the vacuum heat insulating material into a three-dimensional shape, and FIG. 7B is a diagram of the molded product shown in FIG. ) Is a view of the molded product shown in FIG. As is clear from FIG. 7, it was demonstrated that a design-free vacuum heat insulating material capable of forming a three-dimensional shape can be realized.

  As mentioned above, the vacuum heat insulating material 2 which concerns on embodiment of this invention is the inner layer 10 comprised from the laminated sheet 8 by which the inorganic fiber sheet 4 or the inorganic fiber sheet 4 and the resin fiber sheet 6 were arrange | positioned alternately, and A core member 30 having an outer layer 20 composed of a resin fiber sheet 6 disposed so as to be in contact with an upper surface 10a and a lower surface 10b of the inner layer 10 and an outer packaging material 40 in which the core member 30 is sealed under reduced pressure. Therefore, even if it is thin, it has sufficient heat insulating performance and can be molded into a three-dimensional shape. In particular, the hardness of the resin fiber sheet 6 is preferably lower than the hardness of the inorganic fiber sheet 4. As a result, a large number of minute air layers can be formed between the inorganic fiber sheet 4 and the resin fiber sheet 6, so that even if the core member 30 is thin, it has excellent heat insulation performance and is heated when heated. Damage due to a difference in thermal expansion between 4 and the resin fiber sheet 6 can be effectively suppressed.

  Although the embodiments and embodiments of the present invention have been described, the disclosed contents may vary in the details of the configuration, and combinations of elements and changes in the order of the embodiments, embodiments, etc. are claimed in the present invention. It can be realized without departing from the scope and spirit of the present invention.

2 Vacuum insulating material 4, 4a, b Inorganic fiber sheet 6, 6a-c Resin fiber sheet 8 Laminated sheet 10 Inner layer 10a Upper surface 10b Lower surface 20 External layer 30 Core member 40 Outer packaging material 102 Vacuum insulating material 130 Core member 140 Outer packaging material f4 , F6 fiber

Claims (5)

An inner layer composed of an inorganic fiber sheet or a laminated sheet in which inorganic fiber sheets and resin fiber sheets are alternately disposed, and an outer layer composed of a resin fiber sheet disposed so as to contact the upper surface and the lower surface of the inner layer A core member having
An outer packaging material for sealing the core member under reduced pressure;
A vacuum heat insulating material comprising:
The vacuum heat insulating material according to claim 1, wherein the hardness of the resin fiber sheet is lower than the hardness of the inorganic fiber sheet.
The vacuum heat insulating material according to claim 1 or 2, wherein the resin fiber sheet is formed from olefinic short fibers.
4. The vacuum heat insulating material according to claim 1, wherein the fibers of the resin fiber sheet and the inorganic fiber sheet are oriented in substantially the same direction substantially orthogonal to the thickness direction of the sheet. .
  The vacuum heat insulating material according to any one of claims 1 to 4, wherein the core member is disposed inside a joint portion of the outer packaging material.