JP2015113924A - Heat insulation material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gap heat insulation material resolving heat conduction loss generated in a case where two chambers holding a partition plate therebetween are in a cooling state and in a heating state, and attaining a heat insulation material with less heat conduction loss and an electric apparatus using the heat insulation material.SOLUTION: By providing a heat insulation material capable of being buried even in a complex shape by using a heat insulation material in which aerogel to be a nano-porous body of silica is encapsulated, heat transfer with air from the periphery of a partition plate as a heat medium is suppressed, and energy-saving performance of an electric apparatus such as a vending machine or a refrigerator is improved.

Description

  The present invention relates to a heat insulating material used in a vending machine, a refrigerator, a heating furnace, and the like.

Conventionally, in a vending machine, the area | region of the high temperature part and cooling part of goods is created with the partition plate of the heat insulation wall which has partitioned the inside of the store | warehouse | chamber. As a structure of a partition plate, there exists what bordered the partition plate with the steel plate member on L shape (patent documents 1, 2).

  FIG. 10A shows an exploded perspective view of the partition plate 1 of the conventional vending machine described in Patent Document 1. FIG. The partition plate main body 2, the upper frame 3, the rear frame 5, the lower frame 4, the front frame 6 and the packing 7 are included.

  The partition plate 1 includes a partition plate body 2 made of rigid urethane foam, an upper frame 3, a lower frame 4, a rear frame 5, a front frame 6, and a packing 7 for reinforcing the partition plate body 2.

  FIG.10 (b) is an expanded sectional view of the part in which the partition plate 1 is used in the vending machine. In the vending machine, there is a storage room 801 composed of a high temperature part 11 and a low temperature part 12. It is a room for storing canned beverages. The partition plate 1 is disposed between the high temperature part 11 and the low temperature part 12. The vending machine has been reduced in size to save energy, and a sufficient space cannot be provided between the high temperature part 11 and the low temperature part 12.

  The partition plate 1 which is the heat insulation wall of the vending machine configured as described above will be described. As shown in FIG. 10A, the partition plate 1 has a partition plate body 2 covered with an upper frame 3, a lower frame 4, and a rear frame 5. The partition plate 1 is attached to a storage chamber 801 made of rigid urethane foam. The partition plate 1 separates the high temperature part 11 and the low temperature part 12. Goods are stored in each.

  The product in the low temperature part 12 and the product in the high temperature part 11 are stored and sold at the same time. In order to maintain the temperature of the product in the low temperature part 12 and the product in the high temperature part 11, the partition plate 1 blocks heat transfer between them. A vacuum heat insulating material may be used as the partition plate 1.

  Further, when the heat insulating door (not shown) is closed, the gap between the partition plate 1 and the heat insulating door is closed by contraction of the packing 7 attached to the front frame 6. The penetration of heat from the high temperature part 11 to the low temperature part 12 is suppressed.

JP 2006-285730 A JP 10-116385 A

However, in the case of the above conventional partition plate, sufficient heat insulation is not achieved between the high temperature portion and the low temperature portion. Because heat was leaking from the packing. The heat conductivity of the packing was 0.20 W / mK, and heat was transmitted. Although the packing is elastic, the heat conductivity is not low and heat is transferred.
The present invention solves the above-described conventional problems, and provides a heat insulating member that has good heat insulating properties and can be deformed.

In order to solve the conventional problems, the present invention uses a heat insulating material in which an airgel, which is a nanoporous porous body of silica, is enclosed in a bag of a resin film.

  The airgel has a property that the thermal conductivity is smaller than the thermal conductivity 0.028 W / mK of air, and has a thermal conductivity of about 0.013 W / mK to 0.025 W / mK.

  This airgel is a foam containing approximately 85% to 95% by volume of air, and the pore size of the foam is smaller than 68 nm, which is regarded as the mean free path of air, so that low heat conduction is achieved. .

  In addition, since airgel is a foam with very little silica as a solid content, the skeleton has a brittle nature, and once crushed, the volume is greatly reduced.

  By using the airgel block or granule in a bag, it can be applied as an excellent heat insulating material.

  Moreover, in the present invention, a member in which aerogel is sealed in a resin bag or tube is used as a heat insulating material, and is inserted into a gap generated around the partition plate, so that extremely high heat insulating performance can be exhibited. Yes.

  Moreover, according to the dimension of a clearance, it crushes by pressurizing the airgel in a bag, a shrinkable tube is shrunk by heating with respect to the space where the airgel disappeared, and the space is filled up. This absorbs dimensional tolerances and blocks the flow of heat from the gap.

  The vending machine according to the present invention prevents heat conduction through the packing even when there is a temperature difference by cooling and heating the inside of the two chambers sandwiching the partition plate, thereby reducing power consumption, that is, saving energy. It can be carried out.

(A) Schematic cross-sectional schematic diagram of the heat insulating material in the first embodiment, (b) Perspective view of the heat insulating material in the first embodiment. The figure which shows the structural model of the airgel used for the heat insulating material in Embodiment 1 The figure which shows the dimension adjustment method of the heat insulating material in Embodiment (a)-(c). The flowchart which shows the dimension adjustment method of the heat insulating material in Embodiment 2. Schematic cross-sectional schematic diagram of a heat insulating material in Embodiment 3. Schematic cross-sectional schematic diagram of a heat insulating material in Embodiment 4. Schematic cross-sectional schematic diagram of heat insulating material in embodiment 5 Schematic cross-sectional schematic diagram of a heat insulating material insertion structure in the sixth embodiment Schematic cross-sectional schematic diagram of Embodiment 6 of the present invention showing a combination with a conventional heat insulating material (A) Schematic diagram of heat insulation structure of a conventional vending machine described in Patent Document 1, (b) Schematic cross-sectional view of a heat insulating part in a conventional vending machine described in Patent Document 1.

Embodiments of the present invention will be described below with reference to the drawings. Note that the present invention is not limited to the embodiments.
(Embodiment 1)
FIG. 1A shows a cross-sectional view of the heat insulating material 101 in the first embodiment. FIG. 1B shows a perspective view of the heat insulating material 101 in the first embodiment. Moreover, FIG. 2 shows the structural model of the airgel used for a heat insulating material.

The heat insulating material 101 includes an airgel block 102, an air layer 103, and a resin film 104 surrounding them. A rectangular parallelepiped is shown as an example.
<Airgel block 102>
The dimension is defined assuming a rectangular parallelepiped (the smallest rectangular parallelepiped that covers each particle). The maximum particle diameter is the length of the longest side among the three sides of the rectangular parallelepiped. The average particle diameter is a diameter obtained by averaging the average values of the three sides of each particle. Hereinafter, the definition of the dimension is the same.

  Since the airgel block 102 needs to be tightly packed in the heat insulating material 101, the ratio of the three sides (longest side / minimum side) needs to be 1 to 10. More preferably, a ratio of 1 to 5 is good. Pack it in honey by making it close to a cube.

  The airgel block 102 is in the form of particles having corners, the approximate size (maximum dimension) is 5 mm to 50 mm, and the average particle size is 1 to 10 mm.

  When the average particle size is larger than 10 mm, a space is excessively formed when the space is packed, and the spatial density is increased. As a result, the heat insulation is deteriorated.

  If the average particle size is less than 1 mm, the space is tightly packed, but when compressed, it cannot be shrunk and the gaps cannot be insulated.

  The dimension of the heat insulating material 101 is, for example, 30 mm to 100 mm on one side. In order to pack the airgel block 102 into at least nectar, one side of the airgel block 102 is preferably less than or equal to one third of the minimum side of the heat insulating material 101, that is, 10 mm or less.

  The volume ratio of the airgel block 102 in the volume of the heat insulating material 101 needs to be 80% or more in order to ensure heat insulating performance.

  The shape and size are not limited to this, and those having an appropriate particle size can be used depending on the product. However, the sizes of the particles are not uniform and preferably vary around the average value. The airgel block 102 can be packed without gaps.

  The airgel model used is shown in FIG. The gel has fine pores. The basic constituent material is silica particles 201. Silica airgel (hereinafter aerogel) generally has a porous structure including pores 202 on the order of several tens of nm.

  Here, the average hole diameter of the pores 202 is preferably 3 to 68 nm.

  If the average pore size is larger than 68 nm, air can move freely in the pores. The airgel produced in the embodiment is configured in such a way that the pores are not independent but the pores are connected. Therefore, since the air which exists in the pore of an airgel moves freely, the effect which suppresses heat conduction of air will become thin. In the present invention, the resin film 104 is not evacuated but air is present.

Here, when the average pore hole is a pore of 68 nm or less, air is confined in the pore and cannot move freely, so that the heat conduction component of air can be sufficiently suppressed.
On the other hand, the minimum average hole diameter needs to be several tens of nm or more, which is the minimum diameter of the airgel particles. This is because if it is smaller than that, the holes disappear and the heat insulation performance deteriorates. Specifically, the hole diameter is 5 nm or more, preferably 3 nm or more.

  The heat insulating performance of the airgel used is 0.01 W / m · K to 0.02 W / m · K. On the other hand, non-woven fabric, heat insulating glass wool, and sponge using fibers such as PET have a thermal conductivity of 0.04 W / m · K to 0.07 W / m · K. In urethane foam, the thermal conductivity is 0.02 W / m · K to 0.03 W / m · K. Therefore, the airgel of the embodiment has high heat insulation performance. Furthermore, the thermal conductivity of the airgel is smaller than 0.028 W / m · K, which is the thermal conductivity of air.

  Conventionally, there has been a vacuum heat insulating material as a high performance heat insulating material. The vacuum insulation material is made by filling the bag with glass fiber or the like and sealing it, and then pulling out the air inside to create a vacuum. However, since the air does not work as a heat medium, low heat conduction can be obtained. Can not.

  In addition, if the surface of the silica airgel and the wall surface of the pores are hydrophobic with a water contact angle of 110 degrees or more and have a trimethylsilyl group or a methyl group as a functional group on the surface, the water should be submerged. Even if there is, there is no deterioration in the heat insulation performance.

  In the first embodiment, an airgel having a thermal conductivity of 0.015 W / m · K and an average pore diameter of 40 nm is used. However, the present invention is not limited to this as long as it is a general airgel having the above performance. .

Therefore, heat is preferentially passed through the air layer 103 in the gap of the airgel block 102 inside the heat insulating material 101, and a heat insulating material for gap filling that exhibits excellent heat insulating performance is obtained.
<Resin film 104>
Moreover, as the bag which is the resin film 104, a bag made of polyethylene and having a thickness of 0.08 mm is used, but there is no problem even if it is PET, PP or the like. The thickness is preferably 0.025 mm or more and 3 mm or less. If it is thinner than this, there is a problem in strength, and if it is too thick, the effect of heat conduction of the resin itself becomes large, which is not practical.

Further, the resin film 104 also functions to prevent the powder generated from the airgel from leaking.
<Packaging of Airgel Block 102 into Thermal Insulation Material 101>
A bag of a desired size is formed with the resin film 104. The sheet-like resin film 104 is welded or bonded with an adhesive to form a bag. The airgel block 102 is placed in the bag. The bag is vibrated so that the airgel block 102 is jammed. Thereafter, the lid of the bag is welded or sealed with an adhesive so that the air layer 103 is reduced.
<Example 1>
As Example 1, a heat insulating material 101 (FIG. 1B) in which an airgel block 102 was packed in a bag of a resin film 104 was used. The airgel block 102 is sealed with a resin film 104. It was used in place of the packing 7 of the vending machine shown in FIGS. 10 (a) and 10 (b). That is, the heat insulating material 101 in which the airgel block 102 having an average particle diameter of 10 mm was packed in a PE bag was attached to the partition plate body 2 (made of urethane foam).

  If the partition plate body 2 having the heat insulating material 101 is used as shown in FIG. 10B, the heat conductivity is lower than that of the conventional material. I found out. The thermal conductivity was 0.02 W / m · K. Furthermore, since it has compression performance, it was also possible to prevent heat leakage.

Also in the first embodiment, the air layer 103 present in the airgel block 102 packed in the resin film 104 theoretically has a reduced function as a heat medium. As a result, since the air in the airgel block 102 is contained in the bag, it can be handled as an excellent heat insulating material.
(Embodiment 2)
The second embodiment is characterized in that a heat-shrinkable function is imparted to the resin film 104 shown in the first embodiment.

  As the heat-shrinkable resin, a heat-shrinkable resin applying the shape memory effect of plastic by electron beam irradiation was used. “Sumitube” and “Irax Sleeve” (trademark) manufactured by Sumitomo Electric Industries, Ltd. can be used.

  As the material, polyolefin, polyvinylidene fluoride which is a fluorine-based polymer, thermoplastic elastomer, or the like is selected. However, the resin is not limited to this as long as it has shrinkability.

  When these resins are exposed to a temperature of, for example, 100 ° C., the resin shrinks in a certain direction up to about half, and the film increases in the thickness direction, thereby enabling the bag volume to be reduced. The thickness of the resin film 104 is the same as that of the first embodiment.

  As described above, the airgel has a structure that is easily crushed. An outline of the second embodiment using this fact will be described with reference to cross-sectional views of FIGS. 3A to 3C and a flowchart of FIG.

  First, as shown in FIG. 3A, an airgel block 102 is packed into a bag of a heat-shrinkable resin film 104 and sealed to obtain a heat insulating material 101.

  Next, a part of the airgel block 102 in the heat insulating material 101 is crushed by pressurization. As a result, the airgel block 102 in the heat insulating material 101 is atomized to reduce the volume (FIG. 3B). In this state, since the air layer 103 increases in the heat insulating material 101, the heat insulating performance approaches the thermal conductivity side of air. The volume of the heat insulating material 101 is adjusted so as to have a target dimension.

Therefore, as shown in the flowchart, in order to fill the increased air layer 103 in the heat insulating material 101, the heat insulating material 101 itself is heated to apply heat to contract the heat-shrinkable resin film 104, and the bag is contracted. As shown in 3 (c), it is possible to form the high-performance heat insulating material 101 that is slightly thinner. The inside of the resin film 104 is in a slightly pressurized state. There is little possibility of air entering from the outside. It becomes a stable heat insulating material that is not easily affected by the outside.
<Example 2>
As Example 2, this heat insulating material 101 was inserted in place of the packing 7 as a heat insulating member of the vending machine of FIGS. 10 (a) and 10 (b). If this heat insulating material 101 is used, compared with the conventional material, there is no need to compress the gap. This is because it has already been compressed according to the gap. It can be used without degrading the heat insulation performance.

  Moreover, when the bag made of the resin film 104 is not shrunk, the bag becomes too large compared to the inclusion. For this reason, the gap cannot be sufficiently filled. In this embodiment, since it shrinks in accordance with the gap, it is possible to fit into the gap and prevent heat from leaking from the gap.

  In contrast to the thermal conductivity of 0.02 W / m · K in the case of Example 1, the thermal insulation performance was improved to 0.019 W / m · K in Example 2.

  This airgel block 102 or granulated powder (crushed) can be used as a superior heat insulating material by bagging. However, the heat insulating material 101 of the second embodiment is crushed by pressurizing the airgel block 102 in accordance with an arbitrary size. The space where the airgel block 102 disappears is filled by shrinking the shrinkable tube. By this, it is the heat insulating material 101 which made it possible to lose | disappear the layer of only an outer air and to maintain heat insulation performance.

Moreover, you may provide the vent hole in the resin film 104 as needed. Others not described are the same as those in the first embodiment.
(Embodiment 3)
FIG. 5 shows a cross-sectional view of the heat insulating material 101 of the third embodiment. It is the heat insulating material 101 of the airgel in a bag which used the shape of the airgel enclosed as the block of the airgel block 102, and the granule powder 105 of the airgel.

    Here, the airgel block 102 is a square block. It is not rounded. Aerogel granule powder 105 is a particle with at least one rounded part. Preferably, the whole is rounded. The average size of the maximum particle diameter (maximum side length) of each particle is larger in the airgel block 102 than in the airgel granule powder 105.

  As can be seen from the comparison between FIG. 5 and FIG. 1, the airgel granule powder 105 is buried in the portion corresponding to the air layer 103, thereby further reducing the heat transfer through the air layer 103. . Since the airgel granule powder 105 is round, it is easy to enter the gaps in the airgel block 102.

  While the block-shaped airgel has an average diameter of 5 mm or more, the granular powder has a maximum diameter in the range of 0.1 mm to 5 mm.

  There is no problem even if particles of 0.1 mm or less are included, but rather than filling the air layer, it settles there, and it is difficult to play a role of filling the gap of the airgel block 102. is there.

  The third embodiment is characterized in that the heat insulation performance is further improved by filling the gap with the airgel having heat insulation superior to the heat insulation performance of the air by the powder of the granule biting into the gap between the block-shaped lumps. It is said.

  The volume ratio of the airgel block 102: airgel granule powder 105: air layer 103 is, for example, the following formula (1).

Airgel block 102: Aerogel granule powder 105: Air layer 103 = 85: 10: 5 (1)
The total volume of the airgel block 102 and the airgel granule powder 105 is 80 to 95 volume%. In order to ensure heat insulation performance, 80% by volume or more is necessary.
Here, the airgel granule powder 105 is preferably 5 to 15% by volume. If it is larger than 15% by volume, the shape of the heat insulating material 101 cannot be maintained. When the volume is less than 5% by volume, the space between the airgel blocks 102 cannot be sufficiently filled, and the heat insulating performance is not obtained.
The air layer 103 has a volume of 20% or less to ensure heat insulation.
<Example 3>
As Example 3, 10% by volume of airgel granules 105 having an average particle diameter of 0.8 mm was added to an airgel block 102 having an average particle diameter of 8 mm. In contrast to the thermal conductivity of 0.02 W / m · K when the airgel granules 105 were not added, after the addition, the thermal conductivity was 0.017 W / m · K, and the heat insulation performance was improved.

  When the airgel granule powder 105 is encapsulated in the gap between the airgel blocks 102, the airgel granule powder 105 having better heat insulation than the air heat insulation performance fills the gap, thereby further insulating performance. It is characterized by having improved.

  Others not described are the same as those in the first embodiment. Here, the results of Examples 1 to 3 are summarized as Table 1 below.

In Example 2, since the resin film 104 contracted, the air layer 103 was less and the thermal conductivity was smaller than that in Example 1. Furthermore, in Example 3, the air layer was filled with the airgel granule powder 105, the air layer 103 was reduced, and the thermal conductivity was further reduced. It becomes a preferable example in order of Examples 1, 2, and 3.

As described above, the flow of heat is prevented in the low temperature portion 12 and the high temperature portion 11 (FIG. 10B) due to the decrease in thermal conductivity. As a result, the power of the heater and the cooling device for maintaining a predetermined temperature in each part can be reduced. Although it depends on the structure of the low temperature part 12 and the high temperature part 11 and other materials, in the case of the first to third embodiments, heat from the packing 7 that is one side can be prevented. The amount of power can be reduced to a certain extent.
(Embodiment 4)
The fourth embodiment will be described with reference to FIG. FIG. 6 is a cross-sectional view of the heat insulating material 101 according to the fourth embodiment.

  The heat insulating material 101 has a rectangular parallelepiped shape, and the average diameter of the maximum particle diameters of the particles of the silica airgel granular powder 105 parallel to the widest surface of the rectangular parallelepiped is perpendicular to the widest surface. , And the average diameter is made smaller as it goes from the center of the heat insulating material 101 to the outer layer. It is the heat insulating material 101 of the bag airgel characterized by an average diameter becoming finer as it progresses to an outer layer.

  That is, as shown in FIG. 6, the block-shaped airgel block 102 is arranged inside the bag of the resin film 104, and the airgel granule powder 105 is arranged on the outer periphery.

  The airgel in the bag is about 50 mm at the maximum, but the average particle diameter is made finer toward the periphery. This is because when the airgel contained in the bag is crushed by applying an external force, the granule on the surface is preferentially broken, so that the performance of the heat insulating material 101 is hardly deteriorated.

  Since airgel has a fragile property, once a crack occurs, the crack propagates, and after propagation, the air layer 103 bites.

  As a result, a heat transfer path for air is formed, which may cause deterioration in performance of the heat insulating material 101. The present invention is characterized in that a part that is intentionally broken is provided in order to eliminate the influence.

In the above structure, when the airgel contained in the bag of the resin film 104 is crushed by applying an external force, the granule on the surface is preferentially broken, so that the performance as a heat insulating material is hardly deteriorated. There is a thermal insulation performance equivalent to that of the first embodiment.
(Embodiment 5)
FIG. 7 shows a schematic cross-sectional view of a heat insulating material 101 with a reinforcing material corresponding to the fifth embodiment. The airgel block 102 and the airgel granule powder 105 are brittle and fragile due to the structure of the substance. Therefore, when an unintended load is applied, there is a possibility of crushing.

  In this Embodiment 5, in order to prevent this unintentional destruction, it is characterized in that a substance having a higher compressive strength than that of the airgel is blended in such an amount that the heat insulation performance does not deteriorate.

  In this embodiment, the acrylic resin beads 106 are used, but not limited to resin beads, metal particles, ceramic particles, and hard silica may be used.

  By containing this material, even when a certain load is applied, the gap is controlled by the particle diameter, and the performance as a heat insulating material is prevented from being lost by being completely crushed. A function could be added.

  Further, the heat insulation performance deterioration due to the addition of the acrylic resin beads 106 was not observed up to 20% by volume of the total volume of the heat insulating material 101. It was confirmed that when 20% by volume or more was added, heat was transferred by the acrylic resin beads 106, and the performance of thermal conductivity deteriorated. However, there is no effect of maintaining the shape unless it is at least 3% by volume. Preferably, 5% by volume or more is better.

One example of the total volume ratio is Equation 2 below.
Airgel block 102: Acrylic resin beads 106: Air layer 103 = 85: 10: 5 (2)
The airgel block 102 is 80-95% by volume. In order to ensure heat insulation performance, 80% by volume or more is necessary.

  The acrylic resin beads 106 are 3 to 20% by volume for the above reason. The air layer 103 is preferably 20% by volume or less in order to ensure heat insulation.

The particle diameter of the added acrylic resin beads 106 was 5 mm in average particle diameter while the average particle diameter of the airgel was 8 mm. If the diameter ratio is 70% or less and the volume is 1/4 or less, the airgel may be less likely to cause the acrylic resin beads 106 to contact each other. No heat is transferred because there is no contact. Others not described are the same as those in the first embodiment.
(Embodiment 6)
The sixth embodiment relates to an electronic device using any one of the heat insulating materials 101 of the first to fifth embodiments, and an application method will be described with reference to a schematic diagram shown in FIG. FIG. 8 is a cross-sectional view of the storage room 801 in the vending machine.

  The left high temperature part 11 and the right low temperature part 12 in the storage chamber 801 are separated by a partition plate 802. The heat insulating material 101 according to any one of the first to fifth embodiments is inserted into the gap between the storage chamber 801 and the partition plate 802. This made it possible to prevent the heat exchanged from the gap between the left and right spaces.

  In other words, the gap between the partition plate 802 and the storage chamber 801 was filled with the excellent heat insulating material 101, thereby succeeding in improving the energy saving performance as compared with the prior art. The conventional frame portion was replaced with a heat insulating material 101. This is due to the fact that the degree of freedom in shape and heat insulation performance are superior to those of conventional heat insulation materials.

  At the same time, when dismantling for recycling, the work to remove the sponge and packing and the work of removing the adhering sponge and packing as previously done are no longer necessary, and the work efficiency of the dismantling work for recycling is eliminated. Will also be good.

  In the sixth embodiment, the heat insulating material 101 is used alone, but from the viewpoint of cost, even if this heat insulating material 101 is used as a part of a conventional member such as a sponge or packing, an improvement in performance can be expected.

Others not described are the same as those in the first embodiment.
<Example 4>
As Example 4, a cross-sectional schematic diagram of an example in which a sponge, which is a conventional heat insulating member, and the heat insulating material 101 described in any of the above embodiments is combined is shown in FIG. As shown in FIG. 9, a heat insulating sponge 901 having a thickness of 1 mm was disposed above and below a heat insulating material 101 having a thickness of 3 mm. The heat insulating sponge 901 is an elastic body made of a soft urethane foam.

  By forming such an arrangement, even if the insertion dimension is 3 mm or more and 5 mm or less, the heat insulating sponge 901 is preferentially compressed, and the heat insulating material 101 is held as it is. The gap insulation performance could be maintained. Others not described are the same as those in the first embodiment.

  Note that the above embodiments can be combined.

  As described above, the heat insulating material of the present invention is developed as a gap filling heat insulating material in various fields such as electronic devices such as refrigerators and vending machines, general houses, offices, airplanes, theaters, outdoor watching places, outdoor work places, etc. Is possible.

DESCRIPTION OF SYMBOLS 1 Partition plate 2 Partition plate main body 3 Upper frame 4 Lower frame 5 Rear frame 6 Front frame 7 Packing 11 High temperature part 12 Low temperature part 101 Heat insulating material 102 Airgel block 103 Air layer 104 Resin film 105 Aerogel granule powder 106 Acrylic resin beads 201 Silica particle 202 Fine pore 801 Storage chamber 802 Partition plate 901 Thermal insulation sponge

Claims (8)

A heat insulating material characterized in that a plurality of silica airgel blocks having an average pore diameter of 68 nm or less are packed in a resin film. The heat insulating material according to claim 1, wherein the resin film has heat shrinkability. In addition, it contains granular particles of silica airgel,
The silica airgel block is rounded, the granular particles of the silica airgel are rounded,
The heat insulating material according to claim 1 or 2, wherein an average value of each maximum particle diameter of the granular particles of the silica airgel is smaller than an average value of each maximum particle diameter of the block of the silica airgel. The heat insulating material has a rectangular parallelepiped shape,
The average diameter of the maximum particle diameters of the granular particles of the silica airgel in a direction parallel to the widest surface of the rectangular parallelepiped varies with respect to the direction perpendicular to the widest surface,
The heat insulating material according to claim 3, wherein the average diameter decreases as the heat treatment proceeds from the center to the outer layer. The heat insulating material according to any one of claims 1 to 4, further comprising a gap adjusting particle in the heat insulating material. The gap adjusting particles are made of any one of a resin material, a metal material, and a ceramic material whose compressive strength is higher than that of the airgel, and the size thereof is smaller than the average value of the maximum diameter of the block of the silica airgel. The heat insulating material according to claim 5. The surface of the silica airgel and the wall surface of the pores are hydrophobic and exhibit a water contact angle of 110 degrees or more, and have a trimethylsilyl group or a methyl group as a functional group on the surface. The heat insulating material according to any one of 1 to 6. An electronic device characterized in that a gap inside the electronic device is filled with the heat insulating material according to any one of claims 1 to 7 in order to prevent heat transfer.

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