JP5162377B2 - Vacuum heat insulating material, heat insulating box using the same, and refrigerator - Google Patents

Description

  The present invention relates to a vacuum heat insulating material that improves a heat retaining / cooling function and has low environmental burden and excellent recyclability, a heat insulating box using the same, a refrigerator, and the like.

  In recent years, from the viewpoint of global warming, the necessity of reducing the power consumption of home appliances is desired. Among them, refrigerators, air conditioners, and the like are products with particularly high power consumption, and the reduction of power consumption is necessary as a countermeasure against global warming. Taking a refrigerator as an example, if the load in the refrigerator is constant, the power consumption of the refrigerator will depend on the efficiency of the compressor for cooling in the refrigerator and the insulation performance of the heat insulating material related to the amount of heat leakage from the refrigerator. Mostly decided. Therefore, in the technical development of the refrigerator, improvement in the performance of the heat insulating material is required together with the efficiency of the compressor.

  One of the heat insulating materials for solving such problems is a vacuum heat insulating material. A vacuum heat insulating material is produced by putting a core material excellent in heat insulating properties into an outer packaging material having gas barrier properties and evacuating the inside. Glass wool, an inorganic fiber, is used for the core material of the vacuum heat insulating material, and it is commercialized with ultrafine fibers (average fiber diameter: 3 to 5 μm).

  On the other hand, organic fiber core materials are disclosed in the following publications and the like. For example, in Patent Document 1, in a core material for a vacuum heat insulating material containing glass wool and thermoplastic resin fibers, polypropylene, acrylic, polyethylene terephthalate, polyamide, and polyethylene as thermoplastic resin fibers are heated and melted and pressurized. There is described a vacuum heat insulating material having a heat insulating performance excellent in maintaining a shape with high pressure resistance without enclosing an adsorbent by adopting a structure bonded to glass wool.

Patent Document 2 discloses a vacuum heat insulating material in which an inner packaging material containing a core material containing polyester fibers is contained in a decompressed outer packaging material, wherein the polyester fiber has a thickness of 1 to 6 denier, and the inner packaging material is polyethylene terephthalate. In addition, by setting the density of the core material to 150 to 300 Kg / m ³ , a vacuum insulating material having a low thermal burden at the time of production and recycling, excellent in handleability and production efficiency, and good heat insulation over a long period of time is described. .

  In Patent Document 3, a fiber assembly containing at least two types of polyester fibers having different melting points is processed into a sheet form by a thermal bond method or a needle punch method in a sheet-like core material for a vacuum heat insulating material. The low melting point polyester fiber is 110 to 170 ° C., the high melting point polyester fiber is further 20 ° C. or higher, the fiber thickness is 1 to 6 denier, and the blending ratio is 10:90 to 30:70, A good heat insulating vacuum heat insulating material is described which has a low environmental impact during manufacturing and recycling and is excellent in workability.

Patent Document 4 discloses a sheet-like fiber assembly in which the core material contains 50% by weight or more of a polyester fiber having a fiber thickness of 1 to 6 denier, an average fiber diameter of 9 to 25 μm, and the fiber assembly is a needle punch. Is described, and the density of the core material is set to 150 to 300 kg / m ³ , which describes a vacuum insulating material with good thermal insulation that has low environmental impact during manufacturing and recycling and excellent handling properties. Yes.

Patent Document 5 discloses a polyester sheet in which the core material is a sheet-like fiber assembly made of organic fibers, the vacuum heat insulating material thickness after vacuuming of the core material is 0.1 to 5 mm, and the gas adsorbing material is a soft wrapping bag. A non-woven fabric with a fabric weight of 30 to 200 g / m ² and a core material made of polyester fiber, making it easy to handle at the time of production and recycling and having excellent curved surface workability and heat insulation after evacuation. Is described.
Japanese Patent Laid-Open No. 2003-155651 JP 2006-283817 A JP 2006-57213 A JP 2006-29505 A JP 2006-153199 A

However, the techniques disclosed in Patent Documents 1 to 5 which are the above-mentioned publications have the following problems to be solved. For example, in the vacuum heat insulating material described in Patent Document 1, a core that adheres to glass wool by heating and melting (about 180 to 220 ° C.) and pressing (about 1 kg / cm ² ) glass wool and thermoplastic resin fibers. It is a material. Therefore, since the fiber of a thermoplastic resin has a function of an organic binder, the heat insulation performance is lowered due to the influence of outgas.

  In addition, when an appropriate amount of glass wool and thermoplastic resin are mixed and opened evenly and a laminate of a cotton-like mixture is used as the core material, the mixing area of the thermoplastic resin fibers increases the joint area between the fibers, and the heat transfer path However, there is a problem that heat insulation performance decreases. That is, in the case of glass wool and thermoplastic resin fibers, the thermal conductivity is different between the fiber laminate in which the core material is mixed and each fiber laminate, and the heat insulation is greatly inferior in the mixed fiber laminate described in the specification.

Furthermore, although bending of the vacuum insulation material is not described, it is difficult to bend the glass wool core material along the shape of the attached part, and if it is bent forcibly, it is insulated by cutting the glass wool and reducing the thickness of the core material that occurs at the bent part. The performance is inferior. In recent years, glass fiber glass-wool-containing core materials have problems with respect to environmental impact in consideration of dust influence on the human body, reduction of CO ₂ emissions, and recycling-type eco-recycling.

  In the vacuum heat insulating material described in Patent Document 2, the environmental load is small and the recyclability is excellent. However, when the core material is a polyester fiber, the molecule has an ester bond polar group in the molecule, and therefore the water absorption is as high as about 0.4 to 0.5%. In the vacuum heat insulating material, most of the total gas amount after decompression is moisture, and moisture in the air is gradually adsorbed (absorbed) while assembling the core material of the polyester fiber. Since the moisture content of the core material greatly affects the thermal conductivity, a management process is required to prevent moisture removal and moisture re-adsorption immediately before assembling the vacuum heat insulating material.

  Moreover, in the vacuum heat insulating material using the core material of the polyester fiber, as described in the specification, the heat conductivity is as high as 3 mW / m · K or more and the heat insulating performance is inferior. The glass wool used in the current product uses ultrafine fibers having an average fiber diameter of 3 to 5 μm, and has a low thermal conductivity of about 2 mW / m · K. Therefore, even if it is a vacuum insulation material of a new organic fiber, the heat insulation performance like glass wool is calculated | required. As a reason, for example, when a polyester fiber vacuum heat insulating material having poor thermal conductivity is mounted on a refrigerator or the like, there arises a problem that the amount of heat leakage of the refrigerator is high and the reduction in power consumption is small.

  Furthermore, although the details of the bending of the vacuum heat insulating material are not described, it is difficult to bend the polyester fiber core material along the shape of the attached part, and the fiber is cut when bent forcibly, and the vacuum heat insulating material is cut at the bent part. It has the subject that heat insulation performance is inferior by thickness reduction.

  In the vacuum heat insulating material described in Patent Document 3, the environmental load is small and the recyclability is excellent. However, the two types of polyester fiber aggregates having different melting points as the core material have polar groups of ester bonds in the molecule, and therefore the water absorption is as high as about 0.4 to 0.5%. In the vacuum heat insulating material, most of the total gas amount after decompression is moisture, and moisture in the air is gradually adsorbed (absorbed) until the core material of the polyester fiber is assembled. Since the moisture content of the core material greatly affects the thermal conductivity, a management process is required to prevent moisture removal and moisture re-adsorption immediately before assembling the vacuum heat insulating material.

  Further, the fiber assembly is processed into a sheet by a thermal bond method, and the low melting polyester fiber is heated at 110 to 170 ° C. and the high melting polyester fiber is further heated at 20 ° C. or higher. In the two types of polyester fiber vacuum heat insulating materials, as described in the specification, the thermal conductivity is as high as 4 mW / m · K or more, and the heat insulating performance is inferior. The glass wool used in the current product is an ultrafine fiber having an average fiber diameter of 3 to 5 μm and has a low thermal conductivity of about 2 mW / m · K. Therefore, even if it is a vacuum insulation material of a new organic fiber, the heat insulation performance like glass wool is calculated | required. For example, when a vacuum heat insulating material of polyester fiber having poor thermal conductivity is mounted on a refrigerator or the like, for example, there is a problem that the amount of heat leakage of the refrigerator is high and the reduction in power consumption is small.

  Furthermore, although the details of the bending of the vacuum heat insulating material are not described, it is difficult to bend along the shape of the attached part with the polyester fiber core material, and the fiber is cut if it is bent forcibly, and the thickness is reduced at the bent part. It has the subject that the heat insulation performance of a vacuum heat insulating material is inferior.

  In the vacuum heat insulating material described in Patent Document 4, the environmental load is small and the recyclability is excellent. However, in the sheet-like fiber aggregate containing 50% by weight or more of polyester fiber having a core fiber thickness of 1 to 6 denier, the molecule has an ester bond polar group, so that the water absorption is about 0.4 to 0. High value of .5%. In the vacuum heat insulating material, most of the total gas amount after decompression is moisture, and moisture in the air is gradually adsorbed (absorbed) until the core material of the polyester fiber is assembled. Since the moisture content of the core material greatly affects the thermal conductivity, a management process is required to prevent moisture removal and moisture re-adsorption immediately before assembling the vacuum heat insulating material.

  Other fibers contained in the polyester fiber aggregate include polyethylene, polypropylene, acrylic, aramid, nylon, polyvinyl alcohol, polyurethane synthetic fibers, inorganic fibers, natural fibers, etc., and vacuum insulation using this core material Then, as described in the specification, the thermal conductivity is 3 mW / m · K or more, and the heat insulation performance is inferior. The glass wool used in the current product has a low thermal conductivity of about 2 mW / m · K for ultrafine fibers having an average fiber diameter of 3 to 5 μm. Therefore, even a new organic fiber vacuum heat insulating material is required to have a heat insulating performance equivalent to that of glass wool. For example, when a vacuum heat insulating material of polyester fiber having poor thermal conductivity is mounted on a refrigerator or the like, for example, there is a problem that the amount of heat leakage of the refrigerator is high and the reduction in power consumption is small.

  Furthermore, although the details of the bending of the vacuum heat insulating material are not described, it is difficult to bend the polyester fiber core along the shape of the attached part, and if it is forcibly bent, the fiber is cut and the thickness is reduced at the bent part. Therefore, the heat insulation performance of the vacuum heat insulating material is inferior.

  In the vacuum heat insulating material described in Patent Document 5, the environmental load is small and the recyclability is excellent. However, the core material is a sheet-like fiber assembly made of organic fibers, the core material has a thickness of 0.1 to 5 mm after evacuation, the gas adsorbent bag is a polyester fiber nonwoven fabric, and the core material is polyester fiber. A certain molecule has an ester bond polar group, so that the water absorption is as high as about 0.4 to 0.5%. In the vacuum heat insulating material, most of the total gas amount after decompression is moisture, and the polyester fiber wrapping bag and the core material gradually adsorb moisture (absorb moisture) until they are assembled. Since the moisture content of the core material greatly affects the thermal conductivity, a management process is required to prevent moisture removal and moisture re-adsorption immediately before assembling the vacuum heat insulating material.

  Further, when the thickness of the vacuum heat insulating material after evacuation is 0.1 to 5 mm, it is very thin and the heat insulating property is insufficient, and the thermal conductivity is 4 mW / m · K or more as described in the specification. And high values. The glass wool used in the current product has a low thermal conductivity of about 2 mW / m · K for ultrafine fibers having an average fiber diameter of 3 to 5 μm.

  Therefore, even if it is a vacuum insulation material of a new organic fiber, the heat insulation performance like glass wool is calculated | required. The reason for this is that when a polyester fiber vacuum heat insulating material having a small thickness is mounted in a refrigerator or the like, the problem of insufficient heat insulation occurs. In the glass wool vacuum heat insulating material, from the viewpoint of power consumption, the thickness after evacuation is usually about 10 mm from the viewpoint of power consumption. A thin vacuum heat insulating material has excellent bendability, but when used as a heat insulating material for a refrigerator, there is a problem that the effect of reducing the power consumption is small.

The object of the present invention is to provide a thermal conductivity equivalent to that when glass wool is used (2 mW) by using, as a core material of a vacuum heat insulating material, a long fiber web of a polystyrene material that is friendly to the environment consisting of carbon and hydrogen and has low hygroscopicity. / M · K) is to provide a high-performance vacuum heat insulating material. In addition, when using glass wool or polyester fiber, heat conductivity, bendability, moisture removal, degree of dust, and CO ₂ emissions have been improved, which have been the issues of both environmental impact and heat insulation. An object of the present invention is to provide a heat insulating box of a vacuum heat insulating material and a refrigerator that can be recycled.

In order to solve the above problems, the present invention adopts the following configuration.
A core material composed of an organic fiber assembly; a getter agent that adsorbs gas or water vapor; and an outer packaging material having a gas barrier property that houses the core material and the getter agent, and the interior of the outer packaging material is vacuum-sealed. The core material is an oriented web of long fibers directly formed by melt spinning a polystyrene resin that is amorphous and softens near the glass transition temperature , and the core material has a bending elastic modulus. The thermal conductivity is 3000 MPa or more, the initial thermal conductivity is 2.0 mW / mK to 2.8 mW / mK, and the thermal conductivity after standing in a constant temperature bath at 60 ° C. for 30 days is 3.2 mW / mK to 4.4 mW / mK. It is set as the structure which is .

Further, in a space formed by the outer box and the inner box, a heat insulating box body in which a vacuum heat insulating material is installed and filled with a foam heat insulating material, the vacuum heat insulating material is a core material made of an organic fiber assembly, An outer packaging material having a gas barrier property that contains a getter agent that adsorbs gas or water vapor, the core material, and the getter agent, and the inside of the outer packaging material is vacuum-sealed, and the core of the vacuum heat insulating material The material is an oriented web of polystyrene fiber long fibers that is amorphous and softens near the glass transition temperature , and the core material has a flexural modulus of 3000 MPa or more and an initial thermal conductivity of 2.0 mW / mK. To 2.8 mW / mK, and the thermal conductivity after standing for 30 days in a constant temperature bath at 60 ° C. is 3.2 mW / mK to 4.4 mW / mK . Further, the vacuum heat insulating material is installed on the outer box or the inner box in which the space is formed. Furthermore, the said vacuum heat insulating material is bent and installed in the corner | angular part where two surfaces of the said outer box or the said inner box cross | intersect.

  According to the present invention, by using an environmentally friendly polystyrene long fiber web made of carbon and hydrogen as a new core material, the thermal conductivity (2 mW / m · K) equivalent to that of glass wool vacuum heat insulating material is exhibited. A high-performance vacuum heat insulating material can be provided.

Furthermore, as a vacuum heat insulating material that can achieve both heat insulation performance and environmental impact, which was a problem with glass wool and polyester fibers, thermal conductivity, bendability, moisture removal, and CO ₂ emissions are improved, enabling recycling-type eco-recycling. A vacuum heat insulating material, a heat insulating box using the same, and a refrigerator can be provided.

  About the vacuum heat insulating material which concerns on embodiment of this invention, the characteristic on the structure, the function, or an effect | action are demonstrated in detail below. FIG. 1 is a cross-sectional view showing a configuration of a vacuum heat insulating material according to an embodiment of the present invention. In FIG. 1, 1 is a vacuum heat insulating material, 2 is an outer packaging material, 3 is a core material of polystyrene long fiber, and 4 is a getter agent.

  First, the characteristics of the vacuum heat insulating material according to the embodiment of the present invention will be described step by step mainly from the viewpoint of heat insulating performance and environmental load. The feature of this embodiment is an organic fiber core material, a getter agent (which will be described later, which absorbs gas or water vapor), an outer packaging material, and the outer packaging material is sealed under reduced pressure. Lies in the provision of an environmentally friendly long-fiber web made of polystyrene and made of carbon and hydrogen. The core material of the vacuum heat insulating material has a function of a spacer that maintains its shape from atmospheric pressure, and is preferably a fiber having high voids even when subjected to compressive stress during decompression. In addition, since the thermal conductivity, which is an index of heat insulation performance, varies greatly depending on the type of core material, a new core material of polystyrene fiber has been newly selected as an inexpensive general-purpose product and a highly rigid fiber body with low hygroscopicity. And

  The polystyrene used in the present embodiment is preferably a general-purpose polystyrene having a bulky side chain benzene ring, a rigid molecular chain that is difficult to entangle and brittle, and a flexural modulus of about 3000 MPa or more. Polystyrene has a hydrophobic nonpolar group, has a low hygroscopic property, and the molecular weight is not limited as long as it is fiberized, and is preferably about 200,000 to 400,000. For example, when general-purpose polyethylene or polypropylene fibers are used instead of polystyrene fibers, the hygroscopicity is low, but the flexural modulus is low and the creep phenomenon is large. Is as high as 5 mW / m · K or more, and the heat insulation performance is poor.

  As the state of the fiber, if the length is short as a short fiber and the heat conductivity is high, the continuous fiber (continuous indefinite length fiber) and the average fiber diameter are about 20 μm. Hereinafter, 5 to 20 μm is particularly preferable from the viewpoint of thermal conductivity. For example, the stiffness of the fiber is proportional to the product of the fourth power of the fiber diameter and the Young's modulus. Therefore, when the major axis is halved, the stiffness is reduced to 1/16 and becomes very soft and about 5 μm or more. preferable.

  On the contrary, if the fiber diameter is too large, the contact of the fiber becomes close to a line, the thermal conductivity is increased by reducing the contact thermal resistance, and is preferably about 20 μm or less. In addition, the average fiber diameter measured the fiber diameter of the visual field containing about 10 fibers using the scanning electron microscope.

Furthermore, when the density of the core material is 150 Kg / m ³ or less, the strength of the core material decreases and the thermal conductivity tends to increase. On the contrary, if it is 300 kg / m ³ or more, it becomes heavier and the thermal conductivity becomes higher from the viewpoint of porosity and the like. That is, if the density of the core material is too light or too heavy, the heat insulating property tends to decrease, and the preferred density is 150 to 300 Kg / m ³ at the average fiber diameter. The density of the core material is the density after vacuuming contained in the outer packaging material, and the density is calculated from the weight of the core material after subtracting the weight of the outer packaging material and the getter agent from the weight of the vacuum insulation material and the volume of the vacuum insulation material. Calculated.

  The organic fiber aggregate is formed by a long fiber web formed by melt spinning a polystyrene resin, directly extruding from a nozzle and drawing. Polystyrene fibers are spun at an extrusion temperature of about 200 to 320 ° C. When the temperature is low, the extrusion torque increases, and when the temperature is high, the fiber is easily gelled and hardly fiberized. The long fiber aggregate is preferably a core material that is not adhesively bonded by thermal bonding, needle punching, or the like, and is formed and collected so as to produce an oriented web.

  Specifically, polystyrene is extruded from the tip of a nozzle with a melt blown, and fibers are drawn by air jetting and collected on a collector to form a web. In spunbonding, a web is formed in the same manner by continuously extruding from a plurality of spinning nozzle tips and collecting fibers from an ejector on a collector by jetting air. The fiber shape is not limited to a circle, and may be a substantially circular shape, a substantially Y shape, a substantially elliptical shape, a substantially star shape, a substantially polygonal shape, or the like. Can provide a fiber assembly having a relatively small amount. Of course, even if the same long-fiber web as mentioned above is used alone or in combination using a recycled polystyrene resin, it can be used as a vacuum heat insulating material. Further, in order to further increase the temperature of the vacuum heat insulating material of polystyrene long fibers, it is also possible to use a long fiber (for example, polycarbonate, polysulfone, etc.) having a slightly high deformation temperature in combination with the skin layer portion and the like. .

  In a vacuum heat insulating material using polystyrene long fibers as a core material, a vacuum heat insulating material that can be deformed while heating a bent portion and can be bent is obtained as compared with a conventional glass wool or polyester fiber core material. The reason is that polystyrene fibers are amorphous and tend to soften near the glass transition temperature.

  On the other hand, glass wool is difficult to bend, and polyester fibers are crystalline, and even in the vicinity of the glass transition temperature, chain molecules in an amorphous region are connected to and constrained to a crystalline region, so that softening by heating is difficult. That is, amorphous polystyrene tends to soften near the glass transition temperature, and crystalline polyester hardly softens to a temperature at which crystals melt even near the glass transition temperature. The organic fiber tends to be easily bent by heating because the Young's modulus and strength decrease and the elongation increases near the glass transition temperature due to temperature rise.

  In addition, since the core material of glass wool or polyester fiber has high water absorption and has a significant effect on thermal conductivity, for example, when it is glass wool before being inserted into an outer packaging material, a drying treatment of about 300 ° C., polyester fiber In this case, a drying treatment at about 120 ° C. is indispensable. On the other hand, the polystyrene fiber core material of this embodiment has a low water absorption, so that the drying treatment is not particularly necessary.

  The outer packaging material has a material structure that covers the core material provided with an airtight portion therein, and a material that reflects the shape of the core material by vacuum sealing is preferable. For example, if a material having high rigidity is used as the outer packaging material, it becomes difficult to bend, and a pinhole is generated after bending. Accordingly, the outer packaging material is a bag made of a laminate film. The outermost layer corresponding to impact, the intermediate layer ensuring gas barrier properties, and the innermost layer that can be sealed by heat fusion are preferable.

  The outermost layer uses a polyamide film to improve puncture resistance, and an intermediate layer is provided with an ethylene-vinyl alcohol copolymer film having an aluminum vapor deposition layer. The innermost layer is a high density polyethylene, a linear low density polyethylene, a high A density polypropylene is mentioned, A high density polyethylene is preferable from a sealing performance and chemical attack property. For example, a plastic laminate film composed of polyethylene terephthalate as the outermost layer, aluminum foil as the intermediate layer, high-density polyethylene as the innermost layer, polyethylene terephthalate as the outermost layer, and ethylene-vinyl alcohol having an aluminum vapor deposition layer as the intermediate layer. Polymer, plastic laminate film made of high-density polyethylene in the innermost layer, and the like.

  A getter agent is used to improve the reliability of the vacuum heat insulating material. The getter agent only needs to absorb gases such as carbon dioxide, oxygen and nitrogen, and water vapor. The getter agent of dawsonite, hydrotalcite, metal hydroxide, molecular sieves, silica gel, calcium oxide, zeolite, hydrophobic Use absorbents of water-soluble zeolite, activated carbon, potassium hydroxide and lithium hydroxide. At that time, pinholes are likely to be generated in the outer packaging material due to the piercing by the getter agent projection, and therefore pinhole generation in the outer packaging material can be preferably suppressed by using it sandwiched between polystyrene long fibers.

  The vacuum heat insulating material mentioned above can be used for the refrigerator etc. which have a heat insulation box. A refrigerator or the like has a space formed by an outer box and an inner box and is filled with a foamed resin foam, and a vacuum heat insulating material can be inserted into the space filled with the foamed resin foam. The method for inserting the vacuum heat insulating material and the foamed resin is a method in which the vacuum heat insulating material is previously installed in the space formed by the inner box and the outer box, and then the foamed resin foam is injected and integrally molded, or the vacuum heat insulating material There is a method in which a vacuum heat insulating material in which a foamed resin foam is integrally molded in advance is produced and the vacuum heat insulating material is attached to an inner box or an outer box or sandwiched between both. These methods are appropriately used depending on an article that requires heat insulation performance.

  The vacuum heat insulating material described above can be applied to each product that needs to be kept warm. Examples include refrigerators, vehicles, building materials, automobiles, medical equipment, and the like. In particular, it is effective for all products that include a heat exchange section and require heat insulation. By applying the vacuum heat insulating material of the present invention to the refrigerator, it is possible to improve the heat insulation / cooling function and reduce the amount of heat leakage and save energy. Refrigerators and the like include vending machines, product display shelves, refrigerators, cooler boxes and the like in addition to refrigerators and freezers for home use and commercial use. Moreover, by applying it to a vehicle, the space inside the vehicle can be expanded by installing a space-saving vacuum heat insulating material, and a sufficient heat insulating effect can be provided to solve problems such as condensation.

  Next, the structure and manufacturing method regarding the vacuum heat insulating material which concerns on embodiment of this invention, and the refrigerator which applied this are demonstrated below, referring FIGS. FIG. 1 is a cross-sectional view showing a configuration of a vacuum heat insulating material according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing a configuration of a vacuum heat insulating material in the prior art. FIG. 3 is a cross-sectional view showing a configuration of a heat insulating box to which the vacuum heat insulating material according to the present embodiment is applied. FIG. 4 is a cross-sectional view showing a configuration of a refrigerator to which the vacuum heat insulating material according to this embodiment is applied. FIG. 5 is a diagram showing attributes of a plurality of examples, which are specific examples of the vacuum heat insulating material according to the embodiment of the present invention, in comparison with the comparative example.

  In the drawings, 1 is a vacuum heat insulating material, 2 is an outer packaging material, 3 is a core material of polystyrene long fiber, 3 'is a core material bending portion, 4 is a getter agent, 5 is glass wool or polyester fiber, and 6 is a conventional vacuum heat insulating material. , 7 represents a heat insulating box, 8 represents a rigid polyurethane foam, 9 represents a box, 10 represents a refrigerator, 11 represents a refrigerator inner box, and 12 represents a refrigerator outer box.

  The vacuum heat insulating material 1 according to the present embodiment has a configuration in which a core material (core material) 3 of polystyrene long fiber is sealed under reduced pressure with an outer packaging material 2 together with a getter agent 4. According to the vacuum heat insulating material 1 of this embodiment, the planar vacuum heat insulating material 1 having a low thermal conductivity capable of achieving both heat insulating performance and environmental load can be obtained by using the core material 3 of polystyrene long fiber. In addition, by bending the vacuum heat insulating material 1 while heating at about 60 to 80 ° C. which is lower than the welding temperature of the outer packaging material 2, the vacuum heat insulating material having a bent shape with less distortion to the outer packaging material 2 and low thermal conductivity. 1 can also be produced. As a result, an excellent vacuum heat insulating material 1 that can be used in a box and a refrigerator is provided by combining the vacuum heat insulating material 1 having a planar shape or a bent shape.

  On the other hand, the cross-sectional schematic diagram of the conventional vacuum heat insulating material 6 is shown in FIG. It is a vacuum heat insulating material having a configuration in which a glass wool core material or a polyester fiber core material 5 is sealed under reduced pressure with an outer packaging material 2 together with a getter agent 4. The conventional vacuum heat insulating material 6 is good in heat insulation in glass wool, but inferior in environmental load, but in polyester fiber, it has good environmental load but inferior in heat insulation, and a core material that achieves both heat insulation performance and environmental load cannot be obtained. The bendability of the material 5 is also difficult with glass wool or polyester fiber, and if it is bent forcibly, pinholes that occur when the fiber is cut or the thickness is reduced at the bent portion or the outer portion of the outer packaging material 2 becomes thin are likely to occur. Deteriorates thermal insulation performance.

  The perspective schematic diagram of the heat insulation box 7 provided with the vacuum heat insulating material 1 of this embodiment in FIG. 3 is shown. In this heat insulating box 7, the vacuum heat insulating material 1 in which polystyrene long fibers are put is inserted into a part of the inner surface side of the box 9 obtained by press-molding an iron plate, and the rigid polyurethane foam 8 is foam-filled in the gap portion. It is a thing of composition. When the vacuum heat insulating material 1 is manufactured, a vacuum heat insulating material having a bent shape in which a part of the core material 3 is bent by the heating portion 3 ′ is used.

The vacuum heat insulating material of this embodiment was produced by changing the conditions of polystyrene long fibers, and the like, and confirmed thermal conductivity and thermal conductivity deterioration with time, bendability, moisture removal, CO ₂ emission, and eco-recycling. Moreover, what used fiber core materials other than a polystyrene long fiber was produced as Comparative Examples 1-4, and it confirmed similarly. The result of the confirmation is shown in FIG.

  According to FIG. 5, Examples 1 to 5, which are specific examples of the vacuum heat insulating material according to the present embodiment, are listed in comparison with Comparative Examples 1 to 4, and these will be specifically described below.

"Example 1"
The flat plate-shaped vacuum heat insulating material of this embodiment was produced as follows. A general-purpose polystyrene resin (molecular weight: about 200,000, flexural modulus: about 3000 MPa) is used to continuously extrude polystyrene at a temperature of about 290 ° C while passing through the tip of multiple nozzles by spunbond spinning, and control by air injection. The fibers were collected on the collector from the ejector thus formed to form a substantially circular long fiber web. The average fiber diameter is about 15.6 μm and the density is about 230 Kg / m ³ .

  Furthermore, the core material of the long fiber web formed in the outer packaging material made of a gas barrier film is put on top, and the gas adsorption getter agent (Molecular Sieves 13X) is sandwiched between them and diffused for 10 minutes with the rotary pump of the vacuum packaging machine. After pumping in a vacuum chamber for 10 minutes and evacuating until the internal pressure of the chamber became 1.3 Pa, the end of the outer packaging material was vacuum-sealed by heat sealing.

  The thermal conductivity of the obtained vacuum heat insulating material (size: 500 mm × 500 mm × 10 mm) was measured at 10 ° C. using AUTO-Λ manufactured by Eihiro Seiki Co., Ltd. The thermal conductivity was 2.5 mW / m · K, and the vacuum heat insulating material was allowed to stand in a constant temperature bath at 60 ° C. for 30 days, and the thermal conductivity was measured again. The result was 4.2 mW / m · K. From this, the vacuum heat insulating material having a polystyrene long fiber web can provide a high-performance vacuum heat insulating material that is excellent in environmental load and has low hygroscopicity, and that maintains gas barrier properties and internal vacuum.

“Comparative Example 1”
Instead of the polystyrene fiber of Example 1, the polyester fiber aggregate (average fiber diameter: about 16.5 μm, density: about 180 Kg / m ³ ) has high hygroscopicity, so that moisture is removed (dried at 120 ° C./1 h). Using the treated core material, put it in a gas barrier outer packaging material with a gas adsorption getter agent (Molecular Sieves 13X), put it in the vacuum chamber for 10 minutes with the rotary pump of the vacuum packaging machine, 10 minutes with the diffusion pump, After exhausting until the internal pressure became 1.3 Pa, the end portion of the outer packaging material was heat sealed, and a vacuum heat insulating material (size: 500 mm × 500 mm × 10 mm) was produced by vacuum sealing. The vacuum heat insulating material obtained in the same manner as in Example 1 has a thermal conductivity of 4.2 mW / m · K, and the heat conductivity after leaving the vacuum heat insulating material in a constant temperature bath at 60 ° C. for 30 days is restored. The measurement result was 8.2 mW / m · K.

For this reason, the core material using polyester fiber does not have any environmental impact problems (degree of dust, CO ₂ emissions, eco-recycling), but it has a high hygroscopic property and lowers the gas barrier property and internal vacuum. In the heat insulating material, the heat conductivity is high and the heat insulating performance is reduced.

"Example 2"
The bent-shaped vacuum heat insulating material of this embodiment was produced as follows. Using general-purpose polystyrene resin (molecular weight: about 300,000, flexural modulus: about 3200 MPa), polystyrene is continuously extruded at a temperature of about 260 ° C. while passing through the nozzle tip by meltblown spinning, and the fibers are drawn by air injection. Thus, a substantially Y-shaped long fiber web collected on the collector was formed. The average fiber diameter is about 8.0 μm and the density is about 150 Kg / m ³ .

  Furthermore, the core material of the long fiber web formed on the gas barrier outer packaging material is put on top, and the gas adsorption getter agent (hydrophobic zeolite HiSiv-3000) is sandwiched between the rotary pump of the vacuum packaging machine for 10 minutes and the diffusion pump. Place in the vacuum chamber for 10 minutes, exhaust until the internal pressure of the chamber reaches 1.3 Pa, heat seal the end of the outer packaging material, and vacuum seal with vacuum sealing (size: 500 mm x 500 mm x 10 mm) Got. Then, the vacuum heat insulating material was pinched | interposed into the support stand indenter of the bending tester, and the bending-shaped vacuum heat insulating material was produced, heating at the temperature of about 60-80 degreeC.

  As a result of measuring thermal conductivity, it was 2.0 mW / m · K. In addition, in order to evaluate bendability, a bending tester is used to test conditions (speed is 10 mm / min, the distance between fulcrums is 100 mm, the support and indenter is a round bar with a diameter of φ20 mm), and the maximum bending with a displacement of 40 mm The load (N) was measured. As a result, the bendability was as low as 70.5 N, and the heat conductivity after leaving the vacuum heat insulating material in a constant temperature bath at 60 ° C. for 30 days was 3.2 mW / m · K. .

  From this, in the vacuum heat insulating material having the long fiber web of polystyrene, deterioration of the thermal conductivity is suppressed even when it is bent. The bent-shaped vacuum heat insulating material can provide a high-performance vacuum heat insulating material with excellent thermal conductivity without applying excessive stress to the outer packaging material even if it is bent reflecting the core material to be heated.

"Comparative Example 2"
Instead of the polystyrene fiber of Example 2, the polyester fiber aggregate (average fiber diameter: about 17.2 μm, density: about 210 Kg / m ³ ) is highly hygroscopic, so that moisture removal (120 ° C./1 h drying) Using the treated core material, put it in a gas barrier outer packaging material together with a gas adsorption getter agent (hydrophobic zeolite HiSiv-3000), 10 minutes with the rotary pump of the vacuum packaging machine, 10 minutes with the diffusion pump, inside the vacuum chamber After evacuating until the internal pressure of the chamber became 1.3 Pa, the end of the outer packaging material was vacuum-sealed by heat sealing to obtain a vacuum heat insulating material (size: 500 mm × 500 mm × 10 mm).

  After that, while heating with a bending tester as in Example 2, a bent vacuum heat insulating material was formed, but it is difficult to bend. Moreover, as a result of measuring the maximum bending load (N) as in Example 2, the bending property was 120 N, and the thermal conductivity was 5.2 mW / m · K. Thereafter, the thermal insulation was re-measured after leaving the vacuum heat insulating material in a constant temperature bath at 60 ° C. for 30 days, and as a result, the temperature increased to 9.5 mW / m · K.

  Because of this, it is difficult to bend with the polyester fiber core material. It can be seen.

"Example 3"
The flat-plate-shaped vacuum heat insulating material of this embodiment was produced as follows. A general-purpose polystyrene resin is used and a long-fiber web having an approximately circular average fiber diameter of about 20 μm formed by spunbond spinning, and an approximately Y-shaped average fiber diameter formed by meltblown spinning using a general-purpose polystyrene resin is about Both 9.2 μm long fiber webs were used as the core material. The density is about 300 Kg / m ³ . First, using an inner bag of thin polyethylene or the like, both long fiber webs formed by spunbond spinning and meltblown spinning are put together with a gas adsorption getter agent (Molecular Sieves 13X), and after temporary vacuum sealing, further gas barrier properties After opening the inner bag by inserting it into the outer packaging material, immediately put it in the vacuum chamber for 10 minutes with the rotary pump of the vacuum packaging machine and 10 minutes with the diffusion pump, exhaust it until the internal pressure of the chamber becomes 1.3 Pa, and then The edge part of the material was vacuum-sealed by heat sealing to produce a vacuum heat insulating material (size: 500 mm × 500 mm × 10 mm).

  In Example 3, an inner bag that does not affect the thermal conductivity is used as a very easy method for inserting the core material into the outer packaging material. As a result of measuring the thermal conductivity, 2.4 mW / m · K. Furthermore, after placing the vacuum heat insulating material in a thermostat at 60 ° C. and leaving it for 30 days, the thermal conductivity was measured again, and the result was 3.8 mW / m · K. Met.

  Therefore, even a vacuum heat insulating material using two types of polystyrene long fibers having different fiber diameters can provide a high-performance vacuum heat insulating material that has low hygroscopicity and maintains gas barrier properties and internal vacuum.

"Example 4"
The plate-shaped vacuum heat insulating material (size: 500 mm × 500 mm × 10 mm) of Example 3 is bent while the vacuum heat insulating material is sandwiched between the support table indenters of the bending tester and heated at a temperature of about 60 to 80 ° C. The vacuum heat insulating material was produced. As a result of measuring the thermal conductivity, it was 2.8 mW / m · K, which was almost the same as that of a flat plate-shaped vacuum heat insulating material.

  In addition, as a bendability evaluation, a bending tester is used to test conditions (speed is 10 mm / min, distance between fulcrums is 100 mm, a support bar and an indenter is a round bar having a diameter of 20 mm), and a maximum bending load at a displacement of 40 mm. (N) was measured. As a result, the bendability was as low as 72.9 N. Further, the heat conductivity after leaving the vacuum heat insulating material in a constant temperature bath at 60 ° C. for 30 days was 4.4 mW / m · K. .

  From this, even if it is a vacuum heat insulating material which has two types of polystyrene long fiber webs, even if it bends, deterioration of thermal conductivity is controlled. The bent-shaped vacuum heat insulating material can provide a high-performance vacuum heat insulating material with excellent thermal conductivity without applying excessive stress to the outer packaging material even if it is bent reflecting the core material to be heated.

"Example 5"
The flat plate-shaped vacuum heat insulating material of this embodiment was produced as follows. Recycled polystyrene resin (molecular weight: approx. 230,000, flexural modulus: approx. 3500 MPa) is continuously extruded from a refrigerator tray, etc. at a temperature of approx. Fibers were collected on a collector from an ejector controlled by the above, and a substantially circular long fiber web having an average fiber diameter of about 14.2 μm was used. The density of the core material is about 210 kg / m ³ .

  Furthermore, the core material of the long fiber web formed in the gas barrier outer packaging material is put on top, and the gas adsorption getter agent (Molecular Sieves 13X) is sandwiched between the rotary pump of the vacuum packaging machine and 10 minutes with the diffusion pump. Then, after putting in a vacuum chamber and evacuating until the pressure inside the chamber became 1.3 Pa, the end of the outer packaging material was vacuum-sealed by heat sealing. The heat conductivity of the obtained vacuum heat insulating material (size: 500 mm × 500 mm × 10 mm) is 2.6 mW / m · K, and the heat conductivity after leaving the vacuum heat insulating material in a constant temperature bath at 60 ° C. for 30 days. Was 4.1 mW / m · K.

  From this, the vacuum heat insulating material using the polystyrene long fiber of the recycled material can provide a high performance vacuum heat insulating material having excellent heat conductivity by maintaining low gas absorption and low internal gas barrier property. .

"Example 6"
Example 6 of this embodiment is an example in which the vacuum heat insulating material of this embodiment is used in a refrigerator, as shown in FIG. The refrigerator is insulated by a vacuum heat insulating material and other heat insulating materials. In the refrigerator, the temperature difference from the outside air temperature is particularly large between the peripheral portion of the compressor and the outside surface of the inner box on the back of the refrigerator. It is effective to use the vacuum heat insulating material 1 of this embodiment for this part. As the vacuum heat insulating material, a core material of polystyrene long fiber was provided, and a material produced by combining the deformed portion and the flat portion was used.

  The vacuum heat insulating material is a vacuum heat insulating material disposed along the bent portion of the heat insulating wall. When installing a vacuum heat insulating material in the inner box side of a bending part, it has installed so that it may closely_contact | adhere to an inner box along the shape of an inner box. Moreover, the vacuum heat insulating material is installed along the shape of the outer box, when installing in the outer box side of a bending part. The bent part of the heat insulating wall is a part constituting the deformed part of the heat insulating wall. In addition, the vacuum heat insulating material is arrange | positioned also at the back part of an outer box, and the refrigerator door (refer FIG. 4).

  A box and a polyol and isocyanate were injected and filled using a high-pressure foaming machine to prepare a heat insulating material for the refrigerator. Rigid polyurethane foam foam insulation is 40 parts by weight of a polyether polyol obtained by adding propylene oxide to m-tolylenediamine having an average hydroxyl value of 450 as a polyol, and propylene in ortho-tolylenediamine having an average hydroxyl value of 470. 30 parts by weight of polyether polyol with oxide added, 30 parts by weight of polyether polyol with propylene oxide added to o-tolylenediamine having an average hydroxyl value of 380, and 100 parts by weight of mixed polyol component, 15 parts by weight of cyclopentane 1.5 parts of water and 1.2 parts of tetramethylhexamethylenediamine as a reaction catalyst and 2 parts of trimethylaminoethylpiperazine, 2 parts by weight of an organic silicone compound X-20-1614 as a foam stabilizer, and a millionate as an isocyanate component Diphenylmethane diisocyanate polynuclear of R was foam filling with 125 parts.

  The heat leakage amount and power consumption of the refrigerator after heat insulation were measured. The amount of heat leakage of the refrigerator was measured as the amount of heat leakage from the interior by setting the temperature condition opposite to the operation state of the refrigerator. Specifically, a temperature condition in which a refrigerator is installed in a thermostatic chamber of −10 ° C. and the heater temperature is set to a predetermined measurement condition (temperature difference) to compare the power consumption and cooling performance of the refrigerator. Measured with The power consumption of the refrigerator was performed according to JIS measurement standards.

  As a result, it was possible to provide a refrigerator capable of reducing the amount of heat leakage by 8.5% and the power consumption by 12% as compared with a refrigerator in which no vacuum heat insulating material was inserted. In addition, the said rigid polyurethane foam can be used for a refrigerator and a heat insulation box with the vacuum heat insulating material 1 of this embodiment, A phenol foam, a styrene foam, etc. are illustrated other than a rigid polyurethane foam, A rigid polyurethane foam containing cyclopentane and water as a mixed foaming agent is preferred.

"Example 7"
Example 7 of this embodiment is an example in which a vacuum heat insulating material is used as a heat insulating material for a vehicle having a double skin structure material. In a vehicle having a double skin structure, the side surface and the roof structure have a curved surface in order to reduce the weight and improve the pressure resistance, and it is difficult to attach the conventional vacuum heat insulating material. Moreover, when it sticks, a distortion will arise in an outer packaging material, an internal vacuum degree will fall and heat insulation performance will be inferior. The vacuum heat insulating material has a core material of a polystyrene long-fiber web, and was prepared by combining a flat plate shape and a bent shape.

  When the vacuum heat insulating material 1 of the present embodiment is used, it can be attached along the curved surface of the structure, has a heat insulating effect on the vehicle, and does not cause problems such as condensation in the vehicle. In addition, it is a vacuum heat insulating material with excellent heat insulating properties, and the effect of widening the interior space of the vehicle by reducing the thickness of the heat insulating material is also seen, and the vacuum heat insulating material of this embodiment is also effective as a heat insulating material for vehicles. is there.

"Example 8"
Example 8 of this embodiment is an example using a vacuum heat insulating material as a heat insulating material of a vending machine. In vending machines, in order to save energy and improve the space volume, it has a structure with a flat plate vacuum heat insulating material on its side and a bent shape vacuum heat insulating material on the bottom surface. When bent, the outer packaging material is distorted, the internal vacuum is lowered, and the heat insulation performance is deteriorated.

  Therefore, in Example 8, the vacuum heat insulating material 1 has a core material using a polystyrene long fiber web, and is manufactured by combining a flat plate shape and a bent shape.

  By using the vacuum heat insulating material 1 of this embodiment, it can be affixed along the curved surface of the structure, and the rigid polyurethane foam is filled in the box like the refrigerator. Since the vacuum insulation material is flat and bent in shape and has excellent heat insulation characteristics without lowering the internal vacuum, the energy saving and space volume are improved, and the vacuum insulation material of the present invention can be used as a heat insulation material for vending machines. It is valid.

“Comparative Example 3”
Instead of the polystyrene fibers of Examples 1 and 2, glass wool aggregates (density: 250 Kg / m ³ ) with an ultrafine fiber and an average fiber diameter of 4.1 μm have a high hygroscopic property, so moisture removal (about 300 ° C./1 h Using a core material that has been treated with (drying), put it in a gas barrier outer packaging material together with a gas adsorption getter agent 4 (Molecular Sieves 13X), 10 minutes with a rotary pump of a vacuum packaging machine, 10 minutes with a diffusion pump, Then, after exhausting until the internal pressure of the chamber became 1.3 Pa, the end portion of the outer packaging material was heat-sealed, and a vacuum heat insulating material (size: 500 mm × 500 mm × 10 mm) was produced by vacuum sealing.

  The plate-like vacuum heat insulating material thus obtained has a thermal conductivity of 2.0 mW / m · K. As a result of re-measurement of the thermal conductivity after being left in a constant temperature bath at 60 ° C. for 30 days, 3 Excellent 2 mW / m · K. However, although a bending-shaped vacuum heat insulating material was formed, it was difficult to bend and the bending property was measured in the same manner as in Examples 2 and 4. As a result, the maximum bending load was as high as 134 N.

For this reason, in the core material using glass wool, the heat conductivity is low and the heat insulation performance is excellent by incorporating a drying process for removing moisture. However, the shape bendability and the environmental burden (the degree of dust, CO ₂ emissions, eco-recycling) are inferior.

“Comparative Example 4”
Instead of the polystyrene fibers of Examples 1 and 2, a core material of polypropylene fiber aggregate (average fiber diameter: 16.5 μm, density: 180 Kg / m ³ ) is used, and a gas-adsorbing getter agent 4 is used as a gas barrier outer packaging material. (Molecular Sieves 13X), 10 minutes with the rotary pump of the vacuum packaging machine, 10 minutes with the diffusion pump, put into the vacuum chamber, evacuate until the internal pressure of the chamber becomes 1.3 Pa, then heat the end of the outer packaging material A vacuum heat insulating material (size: 500 mm × 500 mm × 10 mm) was prepared by vacuum sealing with a seal.

  The vacuum heat insulating material thus obtained had a thermal conductivity of 5.8 mW / m · K. Further, as a result of remeasurement of the thermal conductivity after being left in a constant temperature bath at 60 ° C. for 30 days, 10. It was 5 mW / m · K. Moreover, although the bending-shaped vacuum heat insulating material was formed, it was difficult to bend and the bending property was measured in the same manner as in Examples 2 and 4. As a result, the maximum bending load was as high as 124N.

For this reason, the core material using polypropylene fiber has no problems with environmental load (degree of dust, CO ₂ emissions, eco-recycling), but the core material of polypropylene fiber is soft and has a low porosity, and the internal vacuum Due to the decrease in the degree of heat, the thermal conductivity is high and the heat insulation performance is poor.

  As described above, according to the embodiment of the present invention, by using a long fiber web of an environmentally friendly polystyrene material made of carbon and hydrogen as a new core material, a thermal conductivity equivalent to that of a glass wool vacuum heat insulating material ( 2 mW / m · K). Furthermore, it can be set as the vacuum heat insulating material which can aim at coexistence of the heat insulation performance and environmental load which were a subject with glass wool or polyester fiber. Moreover, the amount of heat leakage and power consumption can be reduced by mounting the vacuum heat insulating material in the refrigerator and foaming and filling the hard polyurethane foam. In particular, a polystyrene long fiber vacuum heat insulating material is effective for a heat insulating box including a heat exchanging part such as heat insulation and cold insulation, a refrigerator, and the like.

When the vacuum heat insulating material according to the embodiment of the present invention is put together, the following features are provided. That is, a core material composed of an organic fiber assembly, a getter agent that adsorbs gas or water vapor and is disposed in the core material, and an outer packaging material having a gas barrier property that stores the core material and the getter agent, In the vacuum heat insulating material in which the inside of the outer packaging material is vacuum-sealed, the core material has a long fiber web formed by directly spinning an environmentally friendly material composed of carbon and hydrogen (directly formed by melt spinning). is there. And the following can be mentioned as a more preferable structural example. That is, the core material made of carbon and hydrogen is a polystyrene resin. The polystyrene resin is a general-purpose product formed by melt spinning of melt blown and / or spunbond. Further, the core has an average fiber diameter of 8 μm to 20 μm and a density of 150 to 300 Kg / m ³ . Further, the long fiber web of the core material is accommodated inside the inner bag, and the inside including the inner bag in the outer packaging material containing the inner bag is decompressed and sealed.

  In another embodiment of the present invention, a heat insulating box is formed by installing a vacuum heat insulating material in a space formed by an outer box and an inner box and filling with a foam heat insulating material, and the vacuum heat insulating material is a core. The material has at least a polystyrene long-fiber web, and includes an outer packaging material having a gas barrier property in which the core material and the getter agent are encapsulated and the interior is depressurized and sealed. And the following can be mentioned as a more preferable structural example. That is, in the heat insulation box, the vacuum heat insulating material is installed in the outer box or the inner box. Furthermore, in the said heat insulation box, it shall be set as the structure which bends and installs the said vacuum heat insulating material in the corner | angular part where two surfaces of the said outer box or the said inner box cross | intersect.

It is sectional drawing which shows the structure of the vacuum heat insulating material which concerns on embodiment of this invention. It is sectional drawing which shows the structure of the vacuum heat insulating material in a prior art. It is sectional drawing which shows the structure of the heat insulation box which applied the vacuum heat insulating material which concerns on this embodiment. It is sectional drawing which shows the structure of the refrigerator to which the vacuum heat insulating material which concerns on this embodiment is applied. It is a figure showing the attribute about the several Example which is a specific example of the vacuum heat insulating material which concerns on embodiment of this invention compared with a comparative example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vacuum heat insulating material 2 Outer packaging material 3 Core material of polystyrene long fiber 3 'Core material bending part 4 Getter agent 5 Glass wool or polyester fiber 6 Conventional vacuum heat insulating material 7 Heat insulation box 8 Hard polyurethane foam 9 Box 10 Refrigerator 11 In refrigerator Box 12 Refrigerator outer box

Claims (8)

A core material composed of an organic fiber assembly; a getter agent that adsorbs gas or water vapor; and an outer packaging material having a gas barrier property that houses the core material and the getter agent, and the interior of the outer packaging material is vacuum-sealed. Vacuum insulation material,
The core material is an oriented web of long fibers directly formed by melt spinning a polystyrene resin that is amorphous and softens near the glass transition temperature .
The core material has a flexural modulus of 3000 MPa or more, an initial thermal conductivity of 2.0 mW / mK to 2.8 mW / mK, and a thermal conductivity of 3 days after standing in a 60 ° C. constant temperature bath for 3 days. A vacuum heat insulating material characterized by being 2 mW / mK to 4.4 mW / mK . In claim 1 ,
The said polystyrene resin is a general purpose product, Comprising: It forms by melt spinning of a melt blown and / or a spun bond, The vacuum heat insulating material characterized by the above-mentioned. In claim 1 or 2 ,
The vacuum heat insulating material, wherein an average fiber diameter of the core material is 8 μm to 20 μm, and a density of the core material is 150 to 300 Kg / m ³ . In any one of claims 1 to 3 ,
The long fiber web of the core material is stored in an inner bag, the inner bag is stored in the outer packaging material,
The vacuum heat insulating material characterized by depressurizing and sealing the inside including the inner bag in the outer packaging material. A heat insulating box body in which a vacuum heat insulating material is installed and filled with a foam heat insulating material in a space formed by an outer box and an inner box,
The vacuum heat insulating material has a core material made of an organic fiber aggregate, a getter agent that adsorbs gas or water vapor, an outer packaging material having a gas barrier property that houses the core material and the getter agent, and the interior of the outer packaging material Is vacuum sealed,
The core material of the vacuum heat insulating material is an oriented web of long fibers of polystyrene resin that is amorphous and softens near the glass transition temperature ,
The core material has a flexural modulus of 3000 MPa or more, an initial thermal conductivity of 2.0 mW / mK to 2.8 mW / mK, and a thermal conductivity of 3 days after standing in a 60 ° C. constant temperature bath for 3 days. A heat insulation box characterized by being 2 mW / mK to 4.4 mW / mK . In claim 5 ,
The heat insulating box body, wherein the vacuum heat insulating material is installed on the outer box or the inner box in which the space is formed. In claim 5 ,
The said heat insulation box is bent and installed in the corner | angular part where the two surfaces of the said outer box or the said inner box cross | intersect, The heat insulation box characterized by the above-mentioned. A refrigerator comprising the heat insulating box according to claim 5, 6 or 7 .

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