KR20110033203A - Vacuum heat insulating material - Google Patents

Abstract

The vacuum heat insulating material is a fiber constituting the core material, and a fiber obtained by spinning a polymer resin having a bending modulus of 3000 MPa or more, and contains 80% or more of polystyrene fiber as the material. Thereby, it can be set as the vacuum heat insulating material which improves recycling property, reduces environmental load, and reduces material cost.

Description

Vacuum Insulation {VACUUM HEAT INSULATING MATERIAL}

The present invention relates to a vacuum insulator and a refrigerator, a heat insulation box and a heat insulation structure using the same.

In recent years, energy saving is strongly demanded from the viewpoint of preventing global warming, and energy saving has become an urgent problem even for household telephone products. In particular, in the refrigerator, the heat insulating material which has the outstanding heat insulation performance is calculated | required from the viewpoint of using heat efficiently.

As a general heat insulator of a refrigerator, a heat insulator filled with a foamed heat insulating material such as polyurethane foam is widely used between an outer box and an inner box. In order to increase the heat insulating ability in such a heat insulator, it is necessary to increase the thickness of the foamed heat insulating material, but in the refrigerator, space saving and effective use of space are strongly required, and it is difficult to increase the space for filling the foamed heat insulating material. It was.

Therefore, it is proposed to use a vacuum insulator, which is a high-performance insulator, and a foam insulator in combination to form a heat insulator. The vacuum insulator used herein is a heat insulator in which a core material having a role of a spacer is inserted into a packaging material having gas barrier properties, the inside of the packaging material is decompressed and the peripheral edge of the packaging material is sealed.

In the recent vacuum insulator, in order to considerably reduce thermal conductivity, it is mainstream to use inorganic fiber aggregates, such as glass wool which made the fiber system the ultrafine. For example, there is what is disclosed by Unexamined-Japanese-Patent No. 9-138058 (patent document 1). Moreover, the shaping | molding method of the vacuum heat insulating material which laminated glass wool without using the binder which fixes core materials mutually is also proposed by Unexamined-Japanese-Patent No. 2006-112438 (patent document 2).

Thus, although it is glass wool with high demand from heat insulation performance and price, glass lacks recycling property and there exists a problem in discarding.

As a fiber which made much of the recycling property, it is considered that the polymer resin was made into a fiber, for example, the vacuum heat insulating material which made polyethylene terephthalate resin fiber as a core material is proposed by Unexamined-Japanese-Patent No. 2007-239764 (patent document 3). have.

Patent Document 1: Japanese Patent Application Laid-open No. Hei 9-138058 Patent Document 2: Japanese Patent Application Laid-open No. 2006-112438 Patent Document 3: Japanese Patent Application Publication No. 2007-239764

In recent years, from the viewpoint of global warming, a reduction in the amount of power consumed by home appliances has been desired. In particular, since the refrigerator is a product with a large amount of power consumed among home appliances, a vacuum insulator is actively adopted in the heat insulation box of the refrigerator, and the heat insulation box body is used. Is trying to reduce the amount of heat leakage.

However, the core material of the vacuum heat insulating material currently used universally is most inorganic fiber aggregates, such as glass wool. However, glass wool lacks recyclability, and its disposal method becomes a problem at the time of disposal. In order to return the glass wool back to the glass, regeneration processing by high temperature is required, and due to the vacuum insulator put in place for global warming measures, a very large heat load is applied to the environment, and the term is inverted.

As a glass wool substitute material, what fiberized a polymer resin is considered, polyethylene terephthalate resin fiber, etc. are proposed.

However, it was found that the heat insulating performance of the vacuum insulator made of the core material by laminating polyethylene terephthalate resin fibers was less than that of the vacuum insulator made of glass wool as the core material. In these resin fibers, when the atmospheric pressure is applied after vacuum evacuation, the strength of the fibers themselves is insufficient. Therefore, it is considered that the area where the fibers are in close contact with each other increases and the heat distribution increases. When using these resin fibers as a core material, it turned out that securing a porosity becomes a subject.

In the case of the polymer resin, general-purpose resins such as polypropylene and polystyrene are frequently used in home appliances such as refrigerators, air conditioners, televisions, and washing machines. Since these resins are reusable and the closed recycling which returns to the same product is also attracting attention in order to reduce an environmental load, it is desired to obtain a core material by fiberizing using these general-purpose recycled resins.

In particular, these days, the price of the virgin material of these resins is also rising from the rise of crude oil prices, and it is even more so since the cost reduction is easy to anticipate by the application of recycled materials.

However, for example, polystyrene resin is low in glass transition temperature, and it is difficult to apply a vacuum heat insulating material to the core material from a heat resistant viewpoint. For example, when installing a vacuum insulator in the heat insulation space of a refrigerator box body, when foamed urethane foam flows around a vacuum heat insulator, the polystyrene resin fiber of the surface vicinity melts by the influence of the foaming heat, Sticking is seen, leading to deterioration of thermal insulation performance.

In addition, in the polypropylene resin, similarly to the above-mentioned polyethylene terephthalate resin fiber, since the strength of the fiber itself is small, there is a problem that the fibers are crushed and the area in contact with each other increases, leading to deterioration of the thermal insulation performance.

In order to solve the said conventional subject, the objective of this invention is to obtain the vacuum heat insulating material which improves recycling property, reduces an environmental load, and also reduces material cost.

In order to solve the said subject, the vacuum heat insulating material of this invention is a vacuum heat insulating material which has an outer shell material and a core material, The said core material is comprised from the laminated body of the fiber which spun the polymer resin.

In addition, the core material is characterized in that the bending elastic modulus is composed of a laminate of fibers spun a polymer resin of 3000MPa or more.

The fiber spun with the polymer resin is characterized by containing 80% or more of polystyrene fiber.

Moreover, the said core material is comprised from one or more types and three or less types of polymer resin fibers, It is characterized by the fiber laminated body which spun the polymer resin whose glass transition temperature is higher than the said polystyrene fiber except the said polystyrene fiber.

Furthermore, the refrigerator refrigerator of this invention arrange | positions the vacuum heat insulating material which has an outer shell material and a core material in the foam heat insulating material filled between an outer box and an inner box, Comprising: The core material of the said vacuum heat insulating material consists of the laminated body of the fiber which spun the polymer resin. It is characterized by.

Moreover, the heat insulation box of this invention was equipped with any one of said vacuum heat insulating materials. It is characterized by the above-mentioned.

Moreover, the heat insulation structure of this invention was equipped with any one of said vacuum heat insulating materials.

According to this invention, the vacuum heat insulating material which improves recycling property, reduces environmental load, and reduces material cost can be obtained.

1 is a cross-sectional view of a vacuum insulator 10 according to a first embodiment of the present invention.
FIG. 2 is an enlarged sectional view of a main part in FIG. 1. FIG.
3 is a longitudinal sectional view of the refrigerator according to the embodiment of the present invention.

The vacuum heat insulating material of this embodiment is demonstrated, referring FIG. 1 and FIG. 1 is a cross-sectional view of a vacuum insulator 1 according to an embodiment of the present invention, and FIG. 2 is an enlarged cross-sectional view of a main part in FIG. 1.

The vacuum heat insulating material 1 seals the inside of the outer cover material 11 which has gas barrier property, and the inside of the inner bag 12 which compressed and accommodated the core material 20 at the predetermined vacuum pressure, and serves as vacuum heat insulation. It is comprised so that heat insulation performance may be provided.

The core material 20 is composed of an aggregate of fibers 21 having an outer diameter of several micrometers to several tens of micrometers produced by using a fiber material such as polypropylene resin or polystyrene resin, for example.

As a fiberization technique of these resins, techniques known in the world can be applied. For example, the span-bonding system and the melt-blown system used at the time of nonwoven fabric manufacture are mentioned, The resin fiber which adjusted the fiber diameter within the range of 3-30 micrometers is adjusted by adjusting discharge amount, air volume, and a collector speed.

The resin to be used does not have any problem even if it is pellet-shaped, and there is no problem even if it is direct molding from a pulverized product. Moreover, recycled resin from waste home appliances etc. can also be used. When using recycled resin, you may use a polymer additive together for a physical property improvement. Moreover, in order to improve melt flow rate, you may use together lubricating agents, such as a liquid paraffin.

The core material 20 may be maintained in a high vacuum of 20 Pa or less for a long time, even if a stress load is applied when the core is attached to a shell such as a refrigerator with a pressure-sensitive adhesive or the like, or a urethane foam may be used. The bending elastic modulus is set to 3000 MPa or more so that the core material 20 and the fibers 21 to be described later are not crushed even if they are exposed to a compressive load applied to the heat insulating material for a long time.

In other words, the bending elastic modulus of the core material 20 is 3000 MPa so that the predetermined porosity of the aggregate of the fibers 21 can be maintained as set for a long time so that the vacuum insulator 10 can maintain high insulation performance for a long time. I do it as above.

Further, according to the experiment, when the density was less than 3000 MPa, deformation caused by the crushing of the core material 20 became large when the high vacuum degree was used, resulting in insufficient thermal insulation performance.

In addition, as shown in the figure, the inner bag 12 may be used. The inner bag 12 is compressed and stored while degassing the core material 20, and has a gas barrier property and is formed of a synthetic resin film that can be thermally welded, for example, a high density polyethylene resin. In (12), moisture and gas components from the outside do not penetrate. In other words, the core material 20 made of the aggregate of the fibers 21 is configured to be sealed by an inner bag having gas barrier properties so as not to adsorb moisture and gas components contained in the atmosphere.

In addition, the inner bag 12 has a structure in which the inner bag 12 containing the core material 20 can be detached from the outer cover material 11 when the component defect such as poor vacuum degree occurs during handling in the manufacturing process. Consists of

Next, the thermal conductivity in the vacuum heat insulating material of the various experimental examples which changed the core material material, bending elastic modulus, and a structure ratio is demonstrated, referring Table 1. FIG.

(Conventional example)

The vacuum heat insulating material 10 of the prior art example of Table 1 is produced and comprised as follows. As the core material 20, a polymer of fibers 21 having an average fiber diameter of about 4 占 퐉, which is made of glass wool without a binder, and which is solid and without hollow parts is used. After cutting the polymer of this fiber 21 into a predetermined shape, it inserts into the inner bag 12 which consists of a high-density polyethylene film, compresses it, degass | blocks the inside, and seals it. In this state, the surface protective layer is a polyamide film, a polyethylene terephthalate film obtained by depositing aluminum on the first gas barrier layer, a second gas barrier layer on aluminum foil, and a four-layer laminate film on which the thermal welding layer is made of a high density polyethylene film. It is put in the outer shell material 11 which is made up, one end part of the inner bag 12 is opened, a seal is released, and the inside of the outer shell material 11 is vacuumed and sealed so that a vacuum degree of 2.2 Pa may be carried out. In this vacuum heat insulating material 10, the core material density is set to about 250 kg / m <3> normally used for the conventional refrigerator.

The thermal conductivity in the vacuum insulator 10 of this conventional example is set to 100 and compared with the thermal conductivity of the vacuum insulator in the following comparative examples and examples.

(Comparative Example 1)

The vacuum insulator 10 of the first comparative example of Table 1 differs from the conventional example in that the core material is made of polypropylene fiber and the bending elastic modulus of the polypropylene fiber is 1880 MPa. Do.

The heat conductivity ratio of the vacuum heat insulating material 10 of this 1st comparative example came to be a result largely exceeding 250 (direction of heat insulation performance falling) with respect to a conventional example.

(Comparative Example 2)

The vacuum insulator 10 of the second comparative example of Table 1 differs from the conventional example in that the core material is made of polycarbonate fiber and the bending elastic modulus of the polycarbonate fiber is 2800 MPa. Do.

The thermal conductivity ratio of the vacuum heat insulating material 10 of this 2nd comparative example was set to 190 with respect to a prior art example, and it resulted in it being largely exceeding (the direction in which heat insulation performance is inferior) although not as much as a 1st comparative example.

(Third comparative example)

The vacuum heat insulating material 10 of the 3rd comparative example of Table 1 used the core material as the mixed component which is 70% polystyrene fiber and 30% polypropylene fiber, and made the average fiber bending elastic modulus 2874 MPa, The other points are the same as the conventional example.

Although the thermal conductivity ratio of the vacuum heat insulating material 10 of this 3rd comparative example was 175 with respect to the conventional example, and smaller than the 1st comparative example or the 2nd comparative example, it became a result more than the conventional example.

(4th comparative example)

The vacuum heat insulating material 10 of the 4th comparative example of Table 1 used the core material as the mixed component which is 70% polystyrene fiber and 30% polycarbonate fiber, and made the average fiber bending elastic modulus 2915 MPa, The other points are the same as the conventional example.

Although the thermal conductivity ratio of the vacuum heat insulating material 10 of this 4th comparative example was 160 with respect to the prior art example, and became smaller than the 1st comparative example-the 3rd comparative example, it became a result more than the conventional example.

(First embodiment)

The vacuum insulator 10 of the first embodiment of Table 1 differs from the conventional example in that the core material is made of polystyrene fibers and the bending elastic modulus of the polystyrene fibers is 3300 MPa, and the other points are the same as the conventional examples.

The heat conductivity ratio of the vacuum heat insulating material 10 of this 1st Example became 85 with respect to a prior art example, and it resulted in the heat insulation performance improving.

(2nd Example)

The vacuum insulator 10 of the second embodiment of Table 1 has a core material as a mixed component containing 90% of polystyrene fibers and 10% of polypropylene fibers, and has an average fiber bending elastic modulus of 3158 MPa. The other points are the same as the conventional example.

The thermal conductivity ratio of the vacuum heat insulating material 10 of this 2nd Example was set to 90 with respect to a prior art example, but not as much as 1st Example, but the result which heat insulation performance improved.

(Third Embodiment)

The vacuum insulator 10 of the third embodiment of Table 1 has a core material of 80% of polystyrene fibers and 20% of polypropylene fibers, and has an average fiber bending elastic modulus of 3010 MPa. The other points are the same as the conventional example.

The heat conductivity ratio of the vacuum heat insulating material 10 of this 3rd Example was set to 95 with respect to the conventional example, and the result was that heat insulation performance improves with respect to the conventional example.

(Example 4)

In the vacuum insulator 10 of the fourth embodiment of Table 1, the core material is a mixed component having 90% of polystyrene fibers and 10% of polycarbonate fibers, and the average fiber bending modulus is 3145 MPa. The other points are the same as the conventional example.

The thermal conductivity ratio of the vacuum heat insulating material 10 of this 4th Example became 91 with respect to the conventional example, and the result which heat insulation performance improves with respect to the conventional example.

(Fifth Embodiment)

The vacuum insulator 10 of the fifth embodiment of Table 1 is made of polystyrene fibers made of polystyrene taken from waste electrical appliances, so-called recycled polystyrene fibers, and an average fiber bending elastic modulus of 3120 MPa. The other points are the same as the conventional example.

The heat conductivity ratio of the vacuum heat insulating material 10 of this 5th Example became 88 with respect to a prior art example, and it resulted in the heat insulation performance greatly improving.

(Sixth Embodiment)

The vacuum insulator 10 of the sixth embodiment of Table 1 is made of polystyrene fiber made of polystyrene obtained from waste home appliances, so-called recycled polystyrene fiber 90%, and polypropylene made from polypropylene taken from waste home appliances. It differs from the prior art in the point which used as the mixed component of 10% of a fiber, what is called a recycled polypropylene fiber, and made the average fiber bending elastic modulus 3080 MPa, and the other point is the same as the prior art.

The heat conductivity ratio of the vacuum heat insulating material 10 of this 6th Example became 92 with respect to the conventional example, and it resulted in the heat insulation performance improving significantly.

(Seventh Embodiment)

The vacuum insulator 10 of the seventh embodiment of Table 1 is made of polystyrene fiber made of polystyrene obtained from waste home appliances, so-called recycled polystyrene fiber 80%, and polypropylene made from polypropylene taken from waste home appliances. It differs from the prior art in the point which made into the mixed component of 20% of fibers and what is called recycled polypropylene fiber, and made the average fiber bending elastic modulus 3030 MPa, The other points are the same as the prior art.

The heat conductivity ratio of the vacuum heat insulating material 10 of this 7th Example became 97 with respect to the conventional example, and resulted in the big improvement of heat insulation performance.

(Example 8)

The vacuum insulator 10 of the eighth embodiment of Table 1 is made of a laminate of a polystyrene fiber made of polystyrene taken from a waste appliance, a so-called recycled polystyrene fiber, and a polypropylene taken from waste appliances. It is composed by laminating a polypropylene fiber, a laminate of so-called recycled polypropylene fibers, each distribution being 10% recycled polypropylene fiber from the surface, followed by 80% recycled polystyrene fiber, and 10% recycled polypropylene fiber. The average fiber bending elastic modulus is 3018 MPa, which is different from the conventional example, and the other points are the same as the conventional example.

The thermal conductivity ratio of the vacuum insulator 10 of the eighth embodiment is set to 98 relative to the conventional example, resulting in a significant improvement in heat insulation performance.

In addition, the case where the vacuum insulator according to the present invention is mounted in the freezer refrigerator will be described with reference to FIG. 3. 3 is a longitudinal sectional view of a freezer refrigerator according to the embodiment of the present invention.

The box body 30 of the refrigerator comprises a foamed heat insulating material 31 such as urethane and a vacuum heat insulating material 32, 33 in a heat insulating wall 30c including the outer box 30a and the inner box 30b. have. The inside of the box 30 is partitioned and formed in each of the refrigerator compartment 34, the vegetable compartment 35, the ice-making compartment 36, and the freezing compartment 37 sequentially from the top. The refrigerating chamber door 34a, the vegetable chamber door 35a, the ice-making chamber door 36a, and the freezing chamber door 37a are provided so that the front opening of each chamber 34-37 can be opened and closed.

As mentioned above, since the vacuum heat insulating material 10 is arrange | positioned in the refrigerator wall and covers the circumference | surroundings with the foam heat insulating material 31, the surface of a vacuum heat insulating material is exposed to the foaming heat and foaming pressure of a foam heat insulating material. In particular, since general-purpose polystyrene has a low heat resistance temperature, when installed in a thick wall, effects such as deformation shrinkage due to the heat of foaming are also considered.

However, as in the eighth embodiment, by arranging the polypropylene resin fibers having a higher heat resistance temperature than the polystyrene resin on the side in contact with the foamed heat insulating material, the secondary effect of being able to suppress the influence of the foaming heat can also be expected.

In the heat insulating wall located above the height of the center of gravity of the refrigerator, the foamed heat insulating material 31 and the vacuum heat insulating material 32 are provided to reduce the amount of external heat leakage and It is a structure which aims at reducing the weight of the heat insulation wall located above height.

In addition, although the vacuum heat insulating material 33 installed in the heat insulation wall located below the height of the center of gravity of the said refrigerator may use the conventional vacuum heat insulating material, in order to reduce the weight of the whole refrigerator, the vacuum heat insulating material described in the Example You can also use

By making the above structure, the freezer refrigerator of the embodiment of the present invention can reduce the weight of the refrigerator itself, and can provide a refrigerator having a lighter upper portion. Therefore, the freezer refrigerator which is hard to fall even if a left and right shake occurs during an earthquake or transportation. There is also an effect that can provide.

In addition, the vacuum heat insulating material of 1st Example-7th Example mentioned above is set as the structure which uses a heat insulation box body. The heat insulation box is a box requiring heat insulation of a cold or hot device, a heat storage container, a vending machine, an electric water heater, a hot water heater and the like. Thereby, while the heat insulation performance of a heat insulation box body improves, weight reduction and size reduction can be performed.

In addition, the vacuum heat insulating material of 1st Example-7th Example mentioned above is used for the heat insulation structure. An insulation structure is a structure that requires insulation of railroad vehicles, automobiles, building materials, etc. As a result, the heat insulating performance of the heat insulating structure can be improved, and the weight and size can be reduced.

The structure and effect in the vacuum heat insulating material of embodiment mentioned above are put together as follows.

(1) In a vacuum insulator composed of at least an outer shell material and a core material, a recycled resin collected and refined from a virgin material or waste material of a resin that is used for general purposes in household appliances such as polystyrene, polypropylene, polycarbonate, and the like. The material is made of an aggregate of fibrous ones, and the bending elastic modulus of the fiber is 3000 MPa or more, whereby the core material has a strength that can withstand high vacuum for a long time and a relatively lightweight vacuum insulation material.

(2) By securing a bending elastic modulus of 3000 MPa or more of the core material, the fiber itself is light in weight and has strength that can withstand high vacuum for a long time. On the contrary, if it is less than 3000 MPa, the fiber tends to be crushed by atmospheric pressure, and the core material density and the heat transfer area of the solid heat conducting portion are increased together, and the thermal insulation performance is significantly deteriorated.

(3) By setting the bending elastic modulus of the fibers constituting the core material to 3000 MPa or more, it is possible to provide a vacuum heat insulating material having easy handling and bending strength as a fiber laminated state or a vacuum heat insulating material and having good handleability.

(4) Since the fiber constituting the core material is made of an organic fiber material, it is possible to provide a vacuum insulator which is easy to arbitrarily manufacture a shape and size. Moreover, since it is an organic fiber material, the vacuum heat insulating material which improves the recycling property at the time of disposal can be provided.

(5) As the fiber constituting the core material, since recycled resin derived from waste electrical appliances can be used, the closed recycling becomes possible, and the total amount of energy and carbon dioxide emission required for the manufacturing process are small compared with glass wool. We can provide vacuum insulation that is friendly to the global environment.

(6) The vacuum insulator comprises an inner bag for degassing and compressing a core material made of organic fibers such as polystyrene or polycarbonate, and a fiber material having a bending modulus of 3000 MPa or more, and an outer cover material which covers the inner bag in a detachable manner. Since the inner bag is formed of a synthetic resin film that is heat-weldable and does not transmit moisture or gas components in the air, the core material is provided with a vacuum insulator that is hard to adhere to moisture or gas components from the outside. can do.

In addition, since the core material can be stored in the inner bag and the product being manufactured during the manufacturing process can be stored, the degree of freedom in the work process can be improved, and a vacuum insulator can be provided that can improve the overall efficiency. In addition, since only a small amount of moisture or gas components from the outside are attached to the core material, the vacuum evacuation time when the inside of the core material is high in vacuum can be shortened, so that a vacuum insulator can be provided which is advantageous in terms of manufacturing cost. have.

(7) Since the inner bag is detachable from the outer material together with the core material, when a component defect such as poor vacuum degree occurs during handling in the manufacturing process, the inner bag containing the core material is taken out and reused. Since it is possible to provide a vacuum insulator, the recycling rate of the raw materials can be improved.

As described above, by using the polymer resin fibers in the core material, it is possible to be crushed at the same time as the outer material, the inner bag and the adsorbent at the time of disposal, to be recyclable, and to form the fibers using the recycled resin, thereby reducing the environmental load. It is possible to provide a vacuum heat insulating material which can greatly reduce the material cost and also reduce the material cost.

10, 32: vacuum insulation
11: shell material
12: inside pocket
20 core material
21: Fiber
30: box
30a: outer box
30b: inner box
30c: heat insulation wall
31: foam insulation
34a: fridge door
35a: Vegetable Room Door
37a: freezer door

Claims (7)

A vacuum insulator having an outer shell material and a core material, wherein the core material is composed of a laminate of fibers spun with a polymer resin. The method of claim 1,
The core material is a vacuum insulating material, characterized in that the bending elastic modulus is composed of a laminate of fibers spun with a polymer resin of 3000MPa or more. The method of claim 1,
The fiber which spun the said polymer resin contains 80% or more of polystyrene fiber, The vacuum heat insulating material characterized by the above-mentioned. The method of claim 3,
The said core material consists of one or more types and three or less types of polymer resin fibers, and except for the said polystyrene fiber, it is a fiber laminated body which spun the polymer resin with a glass transition temperature higher than the said polystyrene fiber, The vacuum heat insulating material characterized by the above-mentioned. A refrigeration refrigerator, characterized in that a vacuum insulator having an outer shell material and a core material is disposed in the foam insulation filled between the outer box and the inner box, wherein the core material of the vacuum insulator is composed of a laminate of fibers spun with a polymer resin. The heat insulation box provided with the vacuum heat insulating material in any one of Claims 1-4. The heat insulation structure provided with the vacuum heat insulating material in any one of Claims 1-4.

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