JP2016169823A - Heat insulation material, core material, refrigerator, and manufacturing method of heat insulation material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat insulation material that compensates strength poverty of a core material to suppress deterioration of heat insulation performance, even in a case where the core material comprises fiber materials having thin fiber diameters, and a manufacturing method of the heat insulation material including reinforcement means of reinforcing core material strength.SOLUTION: A heat insulation material 10 includes a core material 11 comprising a thin-diameter fiber materials 13 having fiber diameters within a range of a micro order to nano order, and reinforcement means of reinforcing strength of the core material 11. A manufacturing method of the heat insulation material contains a process including the reinforcement means of reinforcing strength of the core material 11.SELECTED DRAWING: Figure 1

Description

  Embodiments of the present invention relate to a heat insulating material, a core material constituting the heat insulating material, a refrigerator including the heat insulating material, and a method for manufacturing the heat insulating material.

  Conventionally, the heat insulating material comprised by accommodating the core material which has a heat insulation function in an outer packaging material is considered (for example, refer patent document 1). In recent years, it has been considered that the core material of this type of heat insulating material is composed of a fiber material. And by reducing the fiber diameter of the fiber material which comprises a core material, the contact area which fiber materials contact decreases, and it can aim at the improvement of heat insulation performance. For this reason, attempts have been made to reduce the fiber diameter of the fiber material constituting the core material. However, if the fiber diameter of the fiber material constituting the core material is reduced, the strength of the fiber material itself is insufficient, and consequently the strength of the core material is insufficient. Therefore, for example, when the inside of the outer packaging material in which the core material is accommodated is decompressed, the fiber material is compressed, the thickness of the heat insulating material is reduced, and at the same time, the contact area between the fiber materials is increased and the heat insulating performance is reduced.

JP 2006-105286 A

  Even if this embodiment is a case where a core material is constituted by a fiber material having a thin fiber diameter, a heat insulating material that can compensate for a lack of strength of the core material and suppress a decrease in heat insulating performance, and this heat insulating material A refrigerator provided and a method for producing the heat insulating material are provided.

The heat insulating material according to the present embodiment includes a core material composed of a fine fiber material having a fiber diameter of micro-order to nano-order, and reinforcing means for reinforcing the strength of the core material.
The manufacturing method of the heat insulating material which concerns on this embodiment includes the process provided with the reinforcement means which reinforces the intensity | strength of the said core material to the core material comprised by the thin fiber material which has a fiber diameter of a micro order to a nano order.

Sectional drawing which shows the structural example of the heat insulating material which concerns on this embodiment Figure showing an enlarged view of part of the fiber material The figure which shows the structural example of a fiber material (the 1) FIG. 2 shows a configuration example of a fiber material (part 2) Flow chart showing an example of manufacturing method of heat insulating material (part 1) Flow chart showing an example of manufacturing method of heat insulating material (part 2) Longitudinal side view showing a configuration example of the main body of the refrigerator Longitudinal front view showing a configuration example of the main body of the refrigerator

  Hereinafter, an embodiment will be described with reference to the drawings. A heat insulating material 10 illustrated in FIG. 1 has a configuration in which a core material 11 constituting a main portion thereof is accommodated in an outer packaging material 12. The core material 11 is composed of a fiber material 13. The outer packaging material 12 constitutes a surface portion of the heat insulating material 10. The outer packaging material 12 is a so-called laminate material in which a metal or metal oxide is vapor-deposited on a resin film of one layer or two or more layers, and has low gas permeability and high airtightness. In this case, the outer packaging material 12 is configured in a bag shape that can accommodate the core material 11. The outer packaging material 12 containing the core material 11 is sealed after the inside is depressurized to a pressure close to vacuum. Thereby, the outer packaging material 12 containing the core material 11 is formed as the vacuum heat insulating material 10.

  The fiber material 13 is formed of a resin fiber material entangled at random. In this case, the fiber material 13 is formed by an electrospinning method. The fiber material 13 produced by the electrospinning method is a thin fiber having a fiber diameter of about 0.1 nm to 10 μm, and a long fiber having a length of, for example, 1000 times or more of the outer diameter. Moreover, the fiber material 13 produced | generated by the electrospinning method makes not the linear form as a whole, but makes the crimped shape curved at random. Thereby, as illustrated in FIG. 2, the fiber material 13 has a configuration having at least one location C where the same fibers contact each other. Therefore, the fiber material 13 has many entanglements between fibers.

  In this case, the fiber material 13 is formed of an organic polymer having a density lower than that of glass. By forming the fiber material 13 with a polymer having a density lower than that of glass, the fiber material 13 can be reduced in weight. The fiber material 13 is polystyrene, polycarbonate, polymethyl methacrylate, polypropylene, polyethylene, polyethylene terephthalate, polybutylene terephthalate, polyamide, polyoxymethylene, polyamideimide, polyimide, polysulfane, polyethersulfane, polyetherimide, poly 1 type selected from ether ether ketone, polyphenylene sulfide, modified polyphenylene ether, syndiotactic polystyrene, liquid crystal polymer, urea resin, unsaturated polyester, polyphenol, melamine resin, epoxy resin, and a copolymer containing these, or 2 It can be formed by blending more than one type of polymer.

  When the fiber material 13 is formed by an electrospinning method, the polymer is made into a solution. Examples of the solvent include isopropanol, ethylene glycol, cyclohexanone, dimethylformamide, acetone, ethyl acetate, dimethylacetamide, N-methyl-2-pyrrolidone, hexane, toluene, xylene, methyl ethyl ketone, diethyl ketone, butyl acetate, tetrahydrofuran, dioxane, A volatile organic solvent such as pyridine or water can be used. Further, the solvent may be one kind selected from the above solvents, or a plurality of kinds may be mixed. This invention is not limited to the said solvent, The above is an illustration.

  When the fiber material 13 is formed by the electrospinning method, since the entanglement between the fibers can be increased, it is possible to form a non-woven fiber sheet simultaneously with the spinning. Further, since the fiber material 13 is formed by the electrospinning method, the fiber diameter can be obtained from the micro order to the nano order, so that the thickness of the fiber sheet per sheet can be made very thin. The heat insulating material 10 comprises the core material 11 by laminating | stacking the fiber material 13 made into the nonwoven fabric-like fiber sheet in this way.

  In addition, by reducing the volume of the gaps between the intertwined fiber materials, the number of the gaps is increased and the heat insulation is improved. For this reason, the fiber diameter of the fiber material 13 is preferably about 5 μm or less, more preferably 1 μm or less, that is, a nano-order fiber diameter. Further, various inorganic fillers such as silicon oxide, metal hydroxide, carbonate, sulfate, and silicate may be added to the fiber material 13. By adding an inorganic filler to the fiber material 13, strength can be improved while maintaining heat insulation. Examples of the inorganic filler to be added include 1 from wollastonite, potassium titanate, zonotlite, gypsum fiber, aluminum porate, MOS (basic magnesium sulfate), aramid fiber, carbon fiber, glass fiber, talc, mica, glass flake and the like. One kind or two or more kinds may be added.

  Next, the structural example which concerns on the fiber material 13 among the heat insulating materials 10 is demonstrated. In the configuration example illustrated in FIG. 3, the fiber material 13 forms a plurality of sheet-like fiber layers. The fiber material 13 may be formed by laminating, for example, several hundred to several thousand fiber layers. In this case, the fiber material 13 constitutes a thin fiber layer 13A and a large fiber layer 13B. The small-diameter fiber layer 13A is a sheet-like fiber layer made of a fine-diameter fiber material having a fiber diameter of micro-order to nano-order. The large-diameter fiber layer 13B is a sheet-like fiber layer composed of a large-diameter fiber material thicker than the small-diameter fiber material. In this case, the large-diameter fiber material has a fiber diameter at least 2 to 3 times that of the small-diameter fiber material.

  The fine fiber material can be obtained by preparing a solution in which, for example, polyamideimide is dissolved in the above solvent at, for example, 10 to 40 wt%, and spinning the solution by an electric spinning device (not shown) by an electric field. And the thin fiber layer 13A can be obtained simultaneously with this spinning. The large-diameter fiber material can be obtained by preparing a solution in which, for example, polyamideimide is dissolved in the above-mentioned solvent at, for example, 10 to 40 wt%, and spinning it by the electric field force using an electrospinning apparatus (not shown). And the large diameter fiber layer 13B can be obtained simultaneously with this spinning. In addition, the manufacturing method of a small diameter fiber material and a large diameter fiber material, 13A of small diameter fiber layers, and the large diameter fiber layer 13B is not restricted to this, A various manufacturing method is employable.

  In this case, the heat insulating material 10 has a configuration in which the thin fiber layers 13A and the large fiber layers 13B are alternately laminated one by one. At this time, the total number of laminated thin fiber layers 13A and large fiber layers 13B may be at least 100 or more. Since the large-diameter fiber layer 13B is made of a thick-diameter fiber material that is thicker than the fine-diameter fiber material constituting the thin-diameter fiber layer 13A, it has higher rigidity and strength than the fine-diameter fiber layer 13A. Therefore, the large-diameter fiber layer 13B reinforces the rigidity and strength of the fine-diameter fiber layer 13A and eventually the core material 11. And the rigidity and intensity | strength as the whole heat insulating material 10 become high by reinforcing the rigidity and intensity | strength of the core material 11 in this way. Therefore, for example, when the pressure inside the outer packaging material 12 in which the core material 11 is accommodated is reduced, the fiber material 13 is hardly compressed. Therefore, an increase in the contact area between the fiber materials 13 can be suppressed, and as a result, the heat insulation performance can be improved.

  In order to improve the heat insulating performance, the heat insulating material 10 basically includes a large diameter fiber layer 13B in a configuration in which the core material 11 is configured by the small diameter fiber layer 13A. The thick fiber layer 13B is made of a thick fiber material that is thicker than the fine fiber material, and has a function as a reinforcing means for reinforcing the strength of the core material 11. According to this structure, even if it is a case where the core material 11 is comprised with the fiber material of a thin fiber diameter, the strength shortage of the core material 11 can be compensated. Therefore, for example, even if the inside of the outer packaging material 12 is depressurized, the fiber material 13 is not easily compressed, and thus the heat insulation performance can be improved.

  Next, a modified configuration example of the fiber material 13 will be described. In the configuration example illustrated in FIG. 4, the fiber material 13 configures a plurality of sheet-like fiber layers. In this case, the fiber material 13 constitutes a mixed fiber layer 13C. The mixed fiber layer 13C is a fiber layer obtained by mixing the above-described thin fiber layer 13A with a large fiber material. In this case, the heat insulating material 10 has a configuration in which a plurality of mixed fiber layers 13C are laminated. For example, the mixed fiber layer 13C is formed by simultaneously injecting a solution prepared for forming a fine fiber material and a solution adjusted for forming a large fiber material from different nozzles provided in an electrospinning device (not shown). Can be obtained. In addition, the manufacturing method of 13 C of mixed fiber layers is not restricted to this, A various manufacturing method is employable.

  Since the mixed fiber layer 13C is configured to include the large-diameter fiber material in the small-diameter fiber layer 13A, the mixed fiber layer 13C has higher rigidity and strength than the single small-diameter fiber layer 13A. Accordingly, the mixed fiber layer 13C reinforces the rigidity and strength of the core material 11 with the large-diameter fiber material constituting a part thereof. And the rigidity and intensity | strength as the whole heat insulating material 10 become high by reinforcing the rigidity and intensity | strength of the core material 11 in this way.

  According to this heat insulating material 10, in order to improve the heat insulating performance, basically, in the configuration mode in which the core material 11 is configured by the thin fiber layer 13A, the large fiber material is mixed in the thin fiber layer 13A. Thus, the mixed fiber layer 13C is configured. The mixed fiber layer 13 </ b> C includes a thick fiber material that is thicker than the thin fiber material, and has a function as a reinforcing means for reinforcing the strength of the core material 11. Therefore, even when the core material 11 is constituted by a fiber material having a thin fiber diameter, the insufficient strength of the core material 11 can be compensated. Therefore, for example, even if the inside of the outer packaging material 12 is depressurized, the fiber material 13 is not easily compressed, and thus the heat insulation performance can be improved.

Next, an example of the manufacturing method of the heat insulating material 10 mentioned above is demonstrated. Here, two manufacturing methods will be described.
(Manufacturing method of laminated insulation)
This manufacturing method is an example of a manufacturing method of the laminated heat insulating material 10 in which the thin fiber layer 13A and the large fiber layer 13B are stacked. As illustrated in FIG. 5, first, a plurality of small-diameter fiber layers 13A and a plurality of large-diameter fiber layers 13B are formed by electrospinning (A1). Then, the thin fiber layer 13A and the large fiber layer 13B are alternately laminated (A2). Thereby, the core material 11 in which the thin fiber layer 13A and the large fiber layer 13B are laminated is formed. Moreover, the core material 11 formed in this way includes a large-diameter fiber material for exhibiting a function as a reinforcing means. That is, this step A2 is an example of a process of providing the core member 11 with reinforcing means. Next, the core material 11 formed in this way is accommodated in the bag-shaped outer packaging material 12 (A3). And if the heat insulating material 10 is manufactured as a vacuum heat insulating material, after accommodating the core material 11 in the outer packaging material 12, the vacuum process which decompresses the said outer packaging material 12 will be performed.

  In addition, 13A of small diameter fiber layers and 13B of large diameter fiber layers may be laminated | stacked alternately one by one, and may be laminated | stacked alternately by multiple sheets. Further, the number of the thin fiber layers 13A may be different from the number of the large fiber layers 13B. When the core material 11 includes a support material (not shown), first, at least one large-diameter fiber layer 13B is laminated on the laminated surface of the support material, and then the large-diameter fiber layer 13B has a small diameter. The fiber layer 13A may be laminated. According to this structure, it becomes the structure by which the large diameter fiber layer 13B which has a function as a reinforcement means is arrange | positioned intensively at the support material side, and can reinforce a support material more firmly.

(Manufacturing method of mixed insulation)
This manufacturing method is an example of a manufacturing method of the mixed heat insulating material 10 in which the mixed fiber layers 13C are laminated. As illustrated in FIG. 6, first, the mixed fiber layer 13C is formed by electrospinning (B1). Then, a plurality of mixed fiber layers 13C are laminated (B2). Thereby, the core material 11 in which the mixed fiber layer 13C is laminated is formed. Moreover, the core material 11 formed in this way includes a large-diameter fiber material for exhibiting a function as a reinforcing means. That is, this step B2 is an example of a process of providing the core member 11 with reinforcing means. Next, the core material 11 formed in this way is accommodated in the outer packaging material 12 (B3). And if the heat insulating material 10 is manufactured as a vacuum heat insulating material, after accommodating the core material 11 in the outer packaging material 12, the vacuum process which decompresses the said outer packaging material 12 will be performed.

  The example of the configuration of the heat insulating material 10 and the example of the manufacturing method have been described above. Next, an embodiment in which the idea according to this embodiment described above is applied to a refrigerator will be described. That is, as illustrated in FIGS. 7 and 8, the main body 101 constituting the outer shell of the refrigerator 100 is a combination of the outer plate 102 and the inner plate 103, and includes a ceiling wall portion 104 and a bottom wall portion 105. , A back wall portion 106, a left wall portion 107, a right wall portion 108, and a machine room wall portion 109. The outer plate 102 is made of metal, for example, and the inner plate 103 is made of resin, for example.

  Each of the walls 104 to 109 has a heat insulating material 10 incorporated therein. In this case, the heat insulating material 10 is a vacuum heat insulating panel in which the inside of the outer packaging material 12 is decompressed. The ceiling wall part 104, the bottom wall part 105, and the machine room wall part 109 include a foam heat insulating material 110 made of, for example, urethane foam, in addition to the heat insulating material 10, between the outer plate 102 and the inner plate 103. On the other hand, the back wall portion 106, the left wall portion 107, and the right wall portion 108 include only the heat insulating material 10 between the outer plate 102 and the inner plate 103. A machine room 111 is formed on the back side of the machine room wall 109. The machine room 111 includes a control device (not shown) that controls the overall operation of the refrigerator 100, a compressor (not shown) that constitutes the refrigeration cycle, and the like. Be placed. The refrigerator 100 is partitioned into a plurality of storage rooms by a partition wall (not shown), and a door (not shown) is attached to each storage room. Thereby, the refrigerator 100 is comprised.

  The heat insulating material according to the present embodiment includes a core material composed of a fine fiber material having a fiber diameter of micro-order to nano-order, and reinforcing means for reinforcing the strength of the core material. According to the present embodiment, even when the core material is constituted by a fiber material having a thin fiber diameter, insufficient strength of the core material can be compensated for and heat insulation performance can be improved.

This embodiment is presented as an example and is not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. This embodiment and its modifications are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.
For example, the heat insulating material according to the present embodiment can be applied to other than the refrigerator. The fiber material may be a glass fiber material instead of a resin fiber material. Further, the heat insulating material may not be evacuated.

  In the drawings, 10 is a heat insulating material, 11 is a core material, 13A is a thin fiber layer, 13B is a large fiber layer (reinforcing means), 13C is a mixed fiber layer (reinforcing means), and 100 is a refrigerator.

Claims (12)

  A heat insulating material comprising: a core material composed of a thin fiber material having a fiber diameter of micro order to nano order; and reinforcing means for reinforcing the strength of the core material.   The heat insulating material according to claim 1, wherein the thin fiber material has at least one location where the same fibers contact each other. The reinforcing means is composed of a thick fiber material having a fiber diameter larger than that of the thin fiber material,
The fine fiber material constitutes a sheet-like fine fiber layer,
The thick fiber material constitutes a sheet-shaped thick fiber layer,
The heat insulating material according to claim 1 or 2, wherein the thin fiber layer and the large fiber layer are laminated. The reinforcing means is composed of a thick fiber material having a fiber diameter larger than that of the thin fiber material,
The fine fiber material constitutes a sheet-like fine fiber layer,
The heat insulating material according to claim 1 or 2, wherein the thick fiber material is mixed in the thin fiber layer.   The heat insulating material according to any one of claims 1 to 4, wherein a fiber diameter of the thin fiber material is 0.1 nm to 10 µm.   The core material with which the heat insulating material of any one of Claim 1 to 5 is equipped.   A refrigerator provided with the heat insulating material of any one of Claim 1 to 5.   The manufacturing method of the heat insulating material which includes the process provided with the reinforcement means which reinforces the intensity | strength of the said core material to the core material comprised by the thin fiber material which has a fiber diameter of a micro order to a nano order.   The manufacturing method of the heat insulating material of Claim 8 using the fiber material which has at least one location where the same fibers contact as the said thin fiber material. The reinforcing means is composed of a thick fiber material having a fiber diameter larger than that of the thin fiber material,
The thin fiber material constitutes a sheet-like thin fiber layer,
The thick fiber material constitutes a sheet-like thick fiber layer,
The manufacturing method of the heat insulating material of Claim 8 or 9 which laminates | stacks the said small diameter fiber layer and the said large diameter fiber layer. The reinforcing means is composed of a thick fiber material having a fiber diameter larger than that of the thin fiber material,
The thin fiber material constitutes a sheet-like thin fiber layer,
The manufacturing method of the heat insulating material of Claim 8 or 9 which mixes the said large diameter fiber material with the said small diameter fiber layer.   The method for producing a heat insulating material according to any one of claims 8 to 11, wherein a fiber material having a fiber diameter of 0.1 nm to 10 µm is used as the thin fiber material.

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