JP2005114123A - Vacuum heat insulating material and application method of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the vacuum heat insulating material capable of controlling the heat radiation by infrared rays effectively, since the conventional method which makes the radiation control material contain in the core material for controlling the radiation heat to get high efficiency of the vacuum heat insulating material is insufficient and the radiation heat is transmitted to the core material as the conductive heat of a solid in addition to the infrared rays that hardly reach into the core material because a protection layer of the external covering material absorbs the infrared rays from the radiation heat when the external covering material for conventional constitution is used. <P>SOLUTION: The radiation heat due to infrared rays is reflected by a radiation heat control film 7 on the surface of the external covering material of the vacuum heat insulating material 1. Hereby, the vacuum insulating material 1 with the excellent heat insulation performance is provided in the temperature range like especially high temperature range about 150°C. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a vacuum heat insulating material and a method for using the vacuum heat insulating material, exhibits an excellent heat insulating effect in a temperature range from room temperature to around 150 ° C., and can be used for equipment that requires heat insulation and heat insulation. The present invention relates to a vacuum heat insulating material.

  In recent years, there has been an active movement to promote energy conservation as a countermeasure against global warming, which is a global environmental problem. Therefore, by adopting vacuum insulation material with high heat insulation performance in jar pots and refrigerator-freezers, jar pots and refrigerator-freezers that suppress heat outflow and intrusion and lower power consumption are provided to prevent global warming. Contributing. Such high-performance vacuum heat insulating materials are expected to be applied to printing machines, copiers, projectors, and the like, and further development of high-performance vacuum heat insulating materials in a temperature range of about 150 ° C. is expected.

  In the temperature region of about 150 ° C., unlike the room temperature region, the radiant heat conduction component by infrared becomes large and cannot be ignored, and the heat conductivity of the vacuum heat insulating material is increased. In order to prevent heat conduction due to this radiation, it is conceivable that the vacuum heat insulating material has a heat radiation suppressing function. As a conventional vacuum heat insulating material, the core material constituting the vacuum heat insulating material includes a radiation suppressing material. (See, for example, Patent Document 1).

  Hereinafter, the conventional vacuum heat insulating material will be described with reference to the drawings.

  FIG. 9 is a cross-sectional view of a conventional vacuum heat insulating material. In FIG. 9, a vacuum heat insulating material 1 wraps a core material 4 formed by bonding an inorganic plate-like filler 2 such as metal or mica, which is excellent in heat reflection, and a hard polyurethane foam pulverized material 3 with an adhesive. It is inserted into the material 5 and molded in a vacuum. The core material 4 is separated into a layer composed mainly of a crushed product 3 of hard polyurethane foam and a layer composed mainly of the plate-like filler 2.

  About the vacuum heat insulating material comprised as mentioned above, the operation | movement is demonstrated below.

In FIG. 9, when this vacuum heat insulating material 1 is applied as a heat insulating member, infrared rays from the heat source to the surface of the high temperature side jacket material pass through the core material 4 and try to go to the low temperature side jacket material. It has been proposed that the infrared rays are reflected by the plate-like filler 2 provided inside the heat insulating material 1, heat conduction due to heat radiation can be prevented, and excellent heat insulating performance can be secured.
Japanese Patent Laid-Open No. 10-300331

  However, in the above conventional configuration, the packaging material constituting the vacuum heat insulating material is usually a thermoplastic resin that can be sealed by welding or the like in the innermost layer, an aluminum foil or the like for the intermediate layer to completely block intrusion of outside air, etc. Since the metal foil and the outermost layer are multi-layer sheets each using a resin that is resistant to scratches, most of the infrared rays traveling from the heat source to the surface of the outer jacket material are absorbed by the resin that is the outermost layer of the packaging material. Since it becomes heat and travels through the metal foil of the intermediate layer, most of infrared rays that cause radiant heat cannot be transmitted to the core material. Therefore, even if a plate-like filler is contained in the core material, the infrared reflection effect is small and it is not very effective as a method for suppressing radiant heat.

  In addition, when a laminate film used as a cover material having a conventional general configuration is used in a temperature range of about 150 ° C., air may enter from the heat-welded layer, and the heat insulation performance may be deteriorated. Further, the protective layer of the laminate film is composed of a non-flame retardant film such as a nylon film or polyethylene terephthalate, and it may be considered that flame retardant is required depending on the application location of the vacuum heat insulating material.

  The present invention solves the conventional problem, and has a means for suppressing radiant heat in the outermost layer of the vacuum heat insulating material, thereby effectively suppressing heat radiation due to infrared rays that increase as the temperature becomes higher. The purpose is to provide materials.

  In addition, the present invention provides a vacuum heat insulating material that can be used in a high temperature range of about 150 ° C. and has flame resistance by providing the laminate structure of the jacket material with heat resistance and flame resistance. The purpose is to do.

  The vacuum heat insulating material of the present invention is composed of a core material and a gas barrier covering material covering the core material, and in the vacuum heat insulating material formed by decompressing the inside of the covering material, at least one surface suppresses radiant heat. A film is provided, and the radiant heat suppression film has an effect of reflecting infrared rays by directing a heat conduction surface provided with the film to a high temperature side.

  By directing the heat conduction surface provided with the radiant heat suppression film to the high temperature side, the radiant heat suppression film has the effect of reflecting infrared rays, thereby preventing the infrared absorption of the vacuum heat insulating material and radiant heat transmitted to the surface of the vacuum heat insulating material By suppressing the above, the heat insulation performance is improved.

  The vacuum heat insulating material according to claim 1 of the present invention is composed of a core material and a gas barrier covering material covering the core material, and is a vacuum heat insulating material formed by decompressing the inside of the covering material. One surface is provided with a radiant heat suppression film.

  By directing the heat conduction surface provided with the film to the high temperature side, the radiant heat suppression film has an effect of reflecting infrared rays. Thereby, the infrared insulation of a vacuum heat insulating material is prevented, and the heat insulation performance improves by suppressing the radiant heat transmitted to the vacuum heat insulating material surface.

  The vacuum heat insulating material according to claim 2 of the present invention is characterized in that, in the invention according to claim 1, the radiant heat suppression film is a metal film.

  The metal film has a high reflectivity and has an effect of effectively reflecting infrared rays. Thereby, the infrared absorption of a vacuum heat insulating material is prevented effectively, and the heat insulation performance improves by suppressing the radiant heat transmitted to the vacuum heat insulating material surface more effectively. In particular, silver, gold, copper, aluminum and the like having high reflectivity are effective.

  The vacuum heat insulating material according to claim 3 of the present invention is the inorganic material multilayer film in which the radiant heat suppression film in the invention according to claim 1 is formed by alternately laminating two kinds of inorganic material films having different refractive indexes. It is characterized by this.

  By alternately laminating inorganic material films having different refractive indexes with a thickness of ¼ of a specific wavelength, the reflected wavefronts from the boundary surfaces of the layers are additively overlapped to selectively reflect far-infrared wavelengths. It has the effect of being able to. Thereby, the infrared absorption of a vacuum heat insulating material is prevented effectively, and the heat insulation performance improves by suppressing the radiant heat transmitted to the vacuum heat insulating material surface more effectively.

  The vacuum heat insulating material according to claim 4 of the present invention is the invention according to any one of claims 1 to 3, wherein the radiant heat suppression film is a film containing a fluorine-based resin. Is.

  The fluororesin has an effect that a fluororesin has a small absorption wavelength in the infrared wavelength region (2 to 25 μm), which is a heat ray, and can be transmitted to a metal film or an inorganic material film without absorbing infrared rays. Thereby, in order to suppress infrared absorption on the surface of the vacuum heat insulating material, the heat insulating performance is improved. Moreover, durability of a radiant heat suppression film can be provided by comprising a fluorine resin in the outermost layer of the radiant heat suppression film.

  The vacuum heat insulating material according to claim 5 of the present invention is the vacuum heat insulating material according to any one of claims 1 to 4, wherein the core material comprises at least a mixture of dry silica powder and conductive powder. It is characterized by this.

  The conductive powder has an action of crushing the aggregation of particles due to the intermolecular interaction of the dry silica powder. Thereby, since the solid contact point per unit volume increases, solid heat resistance becomes high and the heat conduction of a core material falls. The dry silica is specified here because it has a high effect of crushing the agglomerated particles with the conductive powder, and is finer and exhibits an excellent heat insulating effect.

  In addition, the mixture of dry silica powder and conductive powder of this configuration is superior to the core material used for glass wool and other vacuum heat insulating materials in terms of the degree of decrease in heat insulating performance with increasing temperature. Therefore, it is very effective as a vacuum heat insulating material used in a temperature range of about 150 ° C.

  The vacuum heat insulating material according to claim 6 of the present invention is the invention according to any one of claims 1 to 5, wherein the core material includes at least dry silica powder, conductive powder, and inorganic fibers. It is the molded object of the mixture of a powder and a fiber material containing this.

  The fiber material acts as an aggregate inside the molded body, and the core material is easily solidified by general compression molding. Thereby, it is excellent in handleability compared with the case where the core material is a mixture of dry silica powder and conductive powder. In addition, when sealing the jacket material under reduced pressure, the powder does not adhere to the sealing portion, so that the sealing is not hindered, and air gradually enters the inside of the vacuum heat insulating material ( Slow leak) can be prevented, and long-term reliability of the vacuum heat insulating material can be ensured.

  A vacuum heat insulating material according to a seventh aspect of the present invention is the laminate according to any one of the first to sixth aspects, wherein the outer cover material is a gas barrier layer, a heat welding layer, and a protective layer. The heat welding layer is a resin film having a melting point of 200 ° C. or higher, and the resin film melting point of the gas barrier layer and the protective layer is higher than the melting point of the resin film of the heat welding layer. It is what.

  If the operating temperature of the vacuum heat insulating material is set to a temperature lower by 50 ° C. than the melting point of the heat-welded layer, if the melting point of the heat-welded layer is 200 ° C. or higher, the film of the heat-welded layer will melt even in a high temperature atmosphere of about 150 ° C. It is possible to reduce the possibility of peeling between the outer cover material films without taking out, and to suppress the deterioration of the heat insulating performance of the vacuum heat insulating material due to gas intrusion.

  The vacuum heat insulating material according to claim 8 of the present invention is characterized in that, in the invention according to claim 7, the heat-welded layer, the gas barrier layer, and the protective layer are flame retardant. .

  The outer covering material having a laminate structure is made flame retardant, and further has a function of being able to impart flame retardancy as a vacuum heat insulating material, whereby safety at the time of using the vacuum heat insulating material can be improved.

  The vacuum heat insulating material according to claim 9 of the present invention is characterized in that, in the invention according to any one of claim 7 or claim 8, the heat welding layer is a fluororesin film. is there.

  The melting point of the fluorine-based resin film is considerably higher than that of a film generally used as a heat welding layer, and has flame retardancy.

  The vacuum heat insulating material according to claim 10 of the present invention is characterized in that, in the invention according to claim 9, the heat welding layer is a polychlorotrifluorinated ethylene film.

  Polychloroethylene trifluoride is easy to use and economical because it has a low melting point among fluororesin films.

  Invention of Claim 11 of this invention is the heat | fever cutoff member which orient | assigned the surface provided with the radiation heat suppression film of the vacuum heat insulating material as described in any one of Claim 1 to 10 to the high temperature side, Or it is the usage method as a heat retention member.

  The vacuum heat insulating material according to the present invention has excellent heat insulating performance at a relatively high temperature of around 150 ° C. and can be used while maintaining heat insulating performance for a long period of time. It can contribute to energy saving and quality improvement by protecting heat-sensitive parts.

  Embodiments of a vacuum heat insulating material according to the present invention will be described below with reference to the drawings. In addition, about the same structure as the past, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.

  FIG. 1 is a cross-sectional view of a vacuum heat insulating material according to Embodiment 1 of the present invention, FIG. 2 is a characteristic diagram showing the relationship between black body radiation power and wavelength at 150 ° C., and FIG. On the other hand, it is a characteristic diagram showing reflectance when light is projected vertically.

  In FIG. 1, a vacuum heat insulating material 1 is a material in which two jacket materials 6 face each other, cover a core material 4, the inside is decompressed, and the periphery is sealed by heat welding. Among them, the radiant heat suppression film 7 is provided on the upper side disposed on the high temperature side. The film is a thin layer made of a metal, an inorganic material or a semiconductor formed by a foil obtained by thinly stretching a metal, a PVD method, a CVD method, an electrolytic deposition method, or the like, and a laminate of these. Including.

(Embodiment 1)
Examples 1 to 3 show glass wool used for the core material 4 and various materials applied to the radiant heat suppression film 7.

  The covering material 6 used was composed of a heat welding layer 8 made of polychlorotrifluoride ethylene, a gas barrier layer 9 made of aluminum foil, and a protective layer 10 made of polyethylene naphthalate.

(Example 1)
As the radiant heat suppression film 7, a film in which silver (Ag), which is a metal having a high infrared reflection effect, is vapor-deposited on the surface of the jacket material 6 was used.

When heat of 150 ° C. is applied to the high temperature side surface of the vacuum heat insulating material 1 of the present embodiment, the relationship between the wavelength λ and the radiation E _b λ is expressed as shown in FIG. It can be seen that the wavelengths generated from the heat source are concentrated in the far infrared region. At this time, the reflectance when light is projected perpendicularly to the Ag deposition surface is shown as in FIG. 3, and the reflectance in the far-infrared region is a very high value of about 99%. Moreover, since the protective layer 10 absorbs far-infrared rays and becomes heat in the vacuum heat insulating material 1 having the same configuration as that of the present embodiment and which does not form the radiant heat suppression film 7, a large difference appears in the heat insulating performance. it is obvious.

  Although Ag was used as the metal of the present invention, the type and thickness of the material are not limited as long as they have an infrared reflecting function such as gold (Au), aluminum (Al), and copper (Cu). Further, if the reflectance in the wavelength region of 2 to 25 μm is 20% or more, the heat insulation performance is improved, and preferably 50% or more, and a larger heat insulation performance can be obtained by a synergistic effect with the vacuum heat insulating material.

  Moreover, although the formation method of a radiant heat suppression film was made into vapor deposition, although sputtering method, CVD method, the lamination process of metal foil, etc. can be considered, it does not specify in particular as a method of forming a film.

  The thickness of the film is not specified, but the smaller the thickness, the poorer the impact resistance, and the larger the thickness, the higher the solid thermal conductivity as a vacuum heat insulating material. In the case of PVD method or CVD method, the film thickness is preferably in the range of 5 nm to 10 μm, and in the case of metal foil laminating, the range of 1 μm to 30 μm is preferable.

  Moreover, when the oxidation of a metal film surface and a weather resistance become a problem, you may form the film which consists of a fluororesin on the surface of a radiant heat suppression film.

(Example 2)
FIG. 4 is a cross-sectional view of the radiation suppressing film 7 in Example 2. The radiation suppression film 7 is a radiation heat suppression film in which four layers of a first inorganic film 11 made of magnesium fluoride and a second inorganic film 12 made of calcium fluoride and having a different refractive index are alternately laminated.

  By alternately laminating inorganic material films having different refractive indexes with a thickness of ¼ of a specific wavelength, the reflected wavefronts from the boundary surfaces of the layers are additively overlapped to selectively reflect far-infrared wavelengths. It has the effect of being able to. Thereby, the infrared absorption of a vacuum heat insulating material is prevented effectively, and the heat insulation performance improves by suppressing the radiant heat transmitted to a vacuum heat insulating material surface more effectively.

  In the vacuum heat insulating material configured as described above, most of the infrared rays generated from the heat source are reflected by the radiant heat suppression film 10 provided on the surface of the vacuum heat insulating material 1, and thus absorbed by the protective layer 9 of the jacket material 6. Heat leak does not occur. As a result, the thermal conductivity due to radiation transmission can be further reduced, and a reduction in the thermal conductivity of the vacuum heat insulating material can be realized.

  In Example 2 of the present invention, the radiant heat suppression film 7 is formed by alternately laminating magnesium fluoride and calcium fluoride. However, in order to utilize the reflection of the boundary surface, films having different refractive indexes are laminated. The material is not particularly specified. Materials include magnesium fluoride, calcium fluoride, lithium fluoride, barium fluoride, thallium bromoiodide, thallium bromochloride, sodium chloride, potassium bromide, potassium chloride, silicon oxide, cesium iodide, zinc selenide, etc. Can be used.

  Also, the thickness of the film is not particularly specified, but if the thickness is small, the impact resistance is poor, and if the thickness is large, the solid thermal conductivity as a vacuum heat insulating material increases, so the method of forming the radiation suppression film is In the case of PVD method such as vapor deposition or CVD method, the film thickness is preferably in the range of 5 nm to 10 μm, and in the case of laminating metal foil or the like, the range of 1 μm to 30 μm is preferable.

  Moreover, although the installation method of the radiant heat suppression film 10 can consider sputtering, vapor deposition, adhesion | attachment of the film by an adhesive agent etc. to the jacket material 6, it does not specify in particular as a method of forming a film.

  In the first embodiment, the outer cover material 6 is made of polychlorotrifluoroethylene as the heat-welding layer 8, but PET (polyethylene terephthalate) having a melting point of 260 ° C., PEN (polyethylene naphthalate) having a melting point of 270 ° C., CTFE (chlorotrifluoroethylene) having a melting point of 210 ° C., ETFE (copolymer of ethylene tetrafluoride and ethylene) having a melting point of 260 ° C., and FEP (tetrafluoroethylene and propylene hexafluoride) having a melting point of 270 ° C. Copolymers) can be used, and any other film can be used as long as it has a melting point of 200 ° C. or higher and can be heat-welded.

  The gas barrier layer 9 is not particularly specified as long as the gas barrier layer 9 is either a metal foil or a metal-deposited film having a higher melting point than the film used in the heat-welding layer 8. Foil is often used, and other metals with less heat flowing through the metal foil around the vacuum insulation material include iron, nickel, platinum, tin, titanium, stainless steel, carbon steel, and polyimide film with metal vapor deposition. Can be used.

  Further, the protective layer 10 may be a film having a higher melting point than the film used in the heat welding layer 8, specifically, when PET (polyethylene terephthalate) having a melting point of 260 ° C. is used for the heat welding layer, Polyether ketone having a melting point of 330 ° C. can be used. In addition, polysulfone, polyetherimide, or the like can be used, and is not particularly specified as long as it has a higher melting point than the film of the heat welding layer.

  Further, the core material 4 can be an open cell body made of a polymer material such as polystyrene or polyurethane, inorganic and organic powders, inorganic and organic fiber materials, and the like.

(Embodiment 2)
In Embodiment 2, the heat insulation performance was evaluated using various core materials. The radiation suppression film 7 is an Al film having a high infrared reflection effect, and the outer cover material 6 is the same as that of the first embodiment. The heat insulating performance evaluation of this vacuum heat insulating material was to measure the temperature of the low temperature side surface when 150 ° C. heat was applied to the high temperature side surface using a halogen heater.

(Example 3)
As the core material 4, a dry silica powder Aerosil 300 (manufactured by Nippon Aerosil Co., Ltd.) filled in a breathable nonwoven fabric bag was used.

  The temperature of the low temperature side surface of the vacuum heat insulating material 1 in the present example was 60 ° C. The low-temperature side surface temperature of the vacuum heat insulating material with the same specifications and without the radiant heat suppression film is 80 ° C, and the radiant heat suppression film installed on the outer surface of the jacket material reflects the infrared rays to suppress the absorption of infrared rays. I was able to improve.

Example 4
As the core material 4, 5% by weight of Toka Black # 8500F (manufactured by Tokai Carbon Co., Ltd.), which is a conductive powder, is added to Aerosil 300 (Nihon Aerosil Co., Ltd.), which is a dry silica powder, and has air permeability. A non-woven bag was used.

  The temperature on the low temperature side surface of the vacuum heat insulating material 1 in this example was 52 ° C., which was an improvement of 28 ° C. compared to Example 1. This is because carbon black, which is a conductive powder, has the effect of crushing aerosil present in an agglomerated state, and by crushing aerosil, the pore diameter of the core material is reduced. As a result, not only the thermal conductivity of the gas is reduced, but the solid contact point per unit volume is increased by crushing Aerosil, so the solid thermal resistance is increased and the thermal conductivity of the solid is further reduced. is there.

The conductive powder of the present invention may be any conductive powder exhibiting a powder specific resistance value of 1 × 10 ¹³ cm / Ω or less, preferably 1 × 10 ⁸ cm / Ω or less. . In consideration of uniform mixing with the base material, it is preferable that the powder diameter is fine, and the content of the conductive powder is desirably 60 wt% or less, and if it exceeds 60 wt%, the conductive powder The influence of the solid heat conduction of the body itself cannot be ignored, and there is a risk that the heat insulating performance of the vacuum heat insulating material will be deteriorated.

(Example 5)
As core material 4, 5% by weight of Toka Black # 8500F (manufactured by Tokai Carbon Co., Ltd.), which is a conductive powder, is added to Aerosil 300 (manufactured by Nippon Aerosil Co., Ltd.), which is a dry silica powder, and 10% by weight of glass wool is added. The vacuum heat insulating material 1 was produced using the molded object of the mixed powder and fiber material.

  The surface temperature on the low temperature side was 54 ° C. Compared with Example 2, although the heat insulation performance was slightly deteriorated, the handling property was improved. This is because the mixed glass wool has a hydroxyl group on the surface, and thus acts as an aggregate due to an affinity interaction with the hydroxyl group present on the dry silica surface. Moreover, since the core material 4 is a molded object, a nonwoven fabric bag becomes unnecessary and leads to cost reduction of direct material costs.

  In addition, physical adsorption of synthetic zeolite, activated carbon, activated alumina, silica gel, dawsonite, hydrotalcite, etc. to adsorb unpreventable gases that are generated from the core material 4 in the long term or enter the coating material. Long-term reliability can be ensured by using moisture adsorbents and gas adsorbents, such as chemical adsorbents such as oxides and hydroxides of chemicals, alkali metals and alkaline earth metals. It is.

(Embodiment 3)
FIG. 5 is a cross-sectional view of a printing apparatus according to Embodiment 3 of the present invention.

  Printing on the recording paper 15 in the printing device 14 having the fixing device 13 forms an electrostatic charge image on the surface of the photosensitive drum 16, adsorbs toner from the toner storage portion 17, and then passes through the transfer drum 18. Transfer to recording paper 15. The recording paper 15 onto which the toner image has been transferred is carried into the fixing device 13, and the recording paper 15 is passed between a heat fixing roller 19 and a pressure roller 20 kept at a high temperature, whereby the toner is melted and fixed.

  A vacuum heat insulating material 21 was disposed around the heat fixing roller 19 and the pressure roller 20 with the radiant heat suppression film facing the heat fixing roller 19 in order to maintain a predetermined high temperature. Further, in order to prevent the outer frame of the fixing device 13 from being affected by heat, the vacuum heat insulating material 21 is disposed on the entire side surface and the upper surface with the radiant heat suppression film facing the fixing device 13 side. . These vacuum heat insulating materials 21 were configured as shown in Example 4 of the present invention.

  As a result, the infrared rays emitted from the heat fixing roller 19 are reflected by the radiant heat suppression film, so that the heat-sensitive control device (not shown) and the transfer device such as the toner containing portion 17 and the photosensitive drum 16 are adversely affected by the toner. It can be maintained for a long time at 45 ° C. or less.

  Note that the vacuum heat insulating material according to the present invention is not limited to a copying machine as a printing apparatus or a fixing device for a laser printer, but also in a product that needs to insulate or keep warm a heating element of 150 ° C. or less. Can be used.

(Embodiment 4)
FIG. 6 is a sectional view of an electric water heater according to Embodiment 4 of the present invention.

  In FIG. 6, an electric water heater 22 has a hot water storage container 23 for boiling and storing hot water inside the main body, and the upper part is covered with an upper lid 24 that can be opened and closed.

  A donut-shaped heater 25 is closely attached to the bottom surface of the hot water storage container 23, and the controller 26 takes in a signal from the temperature detector 27 and controls the heater 25 to maintain a predetermined temperature. Similarly, a suction port 28 provided on the bottom and a pump 30 driven by a motor 29 through a discharge port 31 which is an outlet for hot water communicate with a hot water discharge pipe 32. The hot water presses a push button 33 to press the motor 29. This is done by starting

  Furthermore, a vacuum heat insulating material 34 is provided on each of the side surface of the hot water storage container 23 and the outer side of the heater 25 on the bottom surface to prevent the heat of the hot water storage container 23 from escaping and lowering the hot water temperature. At this time, the vacuum heat insulating material 34 is disposed with the radiant heat suppression film facing the side surface of the hot water storage container 23 and the heater side of the bottom surface, and the configuration of the vacuum heat insulating material 34 is shown in Example 4 of the present invention. It is a thing.

  By insulating the place where the heat insulating material could not be disposed due to the high temperature from the past, the radiant heat generated from the heater 25 can be suppressed at the same time, so that the power consumption can be reduced by about 6%. Compared to no vacuum insulation, there was a 2 point improvement. Moreover, the performance could be maintained for a long time. Moreover, it is no longer necessary to provide heat insulation by providing a space on the bottom surface of the main body, the volume below the hot water storage container can be reduced, and the hot water supply apparatus can be reduced in size.

(Embodiment 5)
FIG. 7 is a cross-sectional view of a notebook computer according to Embodiment 5 of the present invention. A notebook computer 35 has a CPU 37 and other chips mounted on a printed circuit board 36. Reference numeral 38 denotes a CPU cooling device, which includes a heat transfer block 39 in contact with the CPU and a heat pipe 40 for transferring heat. Reference numeral 41 denotes a heat radiating plate that diffuses and dissipates internal heat. Reference numeral 42 denotes a vacuum heat insulating material according to the fourth embodiment of the present invention, which is attached to the inside of the PC bottom face 43 just below the CPU and the keyboard back face 44 just above the CPU with an adhesive, with the radiation heat suppression film facing the CPU side. doing. Since such a notebook personal computer is equipped with the vacuum heat insulating material 42 shown in the fourth embodiment of the present invention having flame retardancy, the safety is improved and the vacuum is improved like other precision parts inside the personal computer. Thermal insulation can be used. Therefore, it is possible to improve the safety and prevent the heat of the bottom surface of the personal computer and the keyboard surface just above the CPU from causing discomfort to the user for a long period of time. Further, the vacuum heat insulating material 42 can be used in a precision instrument requiring a flame-retardant property in addition to a notebook personal computer.

(Embodiment 6)
FIG. 8 is a sectional view of a projection apparatus (projector) according to Embodiment 6 of the present invention. The DLP projector 45 includes a lamp 46, a DMD element 47, a color filter 48, a ballast 49, a power supply board 50, a control board 51, a cooling fan 52, a lens 53, and a housing 54. Has been.

  The light emitted from the lamp 46 is reflected by the color filter 48, reaches the DMD element 47, and an image is projected through the lens 53.

  Further, the vacuum heat insulating material 55 according to the fourth embodiment of the present invention is disposed between the lamp 46 and the housing 54, and even when the surface temperature of the lamp 46 reaches 180 ° C., the temperature of the housing 54. The rise can be prevented. Further, by disposing the vacuum heat insulating material 55 between the color filter 48 and the control board 51 and between the power supply board 50 and the control board 51, the infrared rays generated from the lamp 46 and the power supply board 50 are reflected, and heat is generated. It is possible to protect a weak electronic circuit board. At this time, the vacuum heat insulating material 55 was disposed with the radiant heat suppression film directed toward the lamp 46 and the power supply substrate 50 as heat sources.

  In this embodiment, the projection apparatus is a one-chip projection type DLP projector, but the same effect can be obtained by using a two-chip projection type or a three-chip projection type. Further, although the projector is a DLP projector, the same effect can be obtained by using a liquid crystal projector.

  The vacuum heat insulating material according to the present invention prevents infrared absorption of the vacuum heat insulating material, can suppress the radiant heat transmitted to the surface of the vacuum heat insulating material and improve the heat insulating performance, and products, facilities, etc. that require high heat insulating properties. Applicable to a wide range of fields.

Sectional drawing of the vacuum heat insulating material in Embodiment 1 of this invention Characteristic diagram showing the relationship between wavelength and blackbody radiation at 150 ° C Characteristic diagram showing reflectivity when light is projected perpendicularly to the Ag deposition surface Sectional drawing of the radiation heat suppression film in Example 2 of Embodiment 1 of this invention Sectional drawing of the printing apparatus in Embodiment 3 of this invention Sectional drawing of the electric water heater in Embodiment 4 of this invention Sectional drawing of the notebook personal computer in Embodiment 5 of this invention Sectional drawing of the projection apparatus in Embodiment 6 of this invention Cross section of conventional vacuum insulation

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vacuum heat insulating material 4 Core material 6 Cover material 7 Radiation heat suppression film 8 Heat welding layer 9 Gas barrier layer 10 Protective layer 11 First inorganic film 12 Second inorganic film 21 Vacuum heat insulating material 34 Vacuum heat insulating material 42 Vacuum heat insulating material 55 Vacuum heat insulating material Material

Claims (11)

In a vacuum heat insulating material that is composed of a core material and a gas barrier outer covering material that covers the core material, and is formed by reducing the pressure inside the outer cover material, a radiation heat suppression film is provided on at least one surface of the heat conducting surface. The vacuum heat insulating material characterized by becoming. The vacuum heat insulating material according to claim 1, wherein the radiant heat suppression film is a metal film. The vacuum heat insulating material according to claim 1, wherein the radiant heat suppression film is an inorganic material multilayer film in which two types of inorganic material films having different refractive indexes are alternately laminated. The vacuum heat insulating material according to any one of claims 1 to 3, wherein the radiant heat suppression film is a film containing a fluorine-based resin. The vacuum heat insulating material according to any one of claims 1 to 4, wherein the core material comprises at least a mixture of dry silica powder and conductive powder. 6. The core material according to claim 1, wherein the core material is a molded body of a mixture of a powder and a fiber material including at least a dry silica powder, a conductive powder, and inorganic fibers. The vacuum heat insulating material according to one item. The jacket material has a laminate structure including a gas barrier layer, a heat-welded layer, and a protective layer, and the heat-welded layer is a resin film having a melting point of 200 ° C. or more, and the resin film of the gas barrier layer and the protective layer The vacuum heat insulating material according to any one of claims 1 to 6, wherein a melting point of is higher than a melting point of the resin film of the heat-welded layer. The heat insulation layer, the gas barrier layer, and the protective layer are flame retardant, and the vacuum heat insulating material according to claim 7. The vacuum heat insulating material according to any one of claims 7 and 8, wherein the heat welding layer is a fluorine resin film. The vacuum heat insulating material according to claim 9, wherein the heat welding layer is a polychlorotrifluoride ethylene film. The usage method as a heat | fever interruption | blocking member or heat retention member which turned the surface provided with the radiant heat suppression film of the vacuum heat insulating material as described in any one of Claims 1-10 to the heat-source side.

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