WO2015026116A1

WO2015026116A1 - Insulation sheet, manufacturing method therefor, and insulation panel using same

Info

Publication number: WO2015026116A1
Application number: PCT/KR2014/007638
Authority: WO
Inventors: 황승재
Original assignee: 주식회사 아모그린텍
Priority date: 2013-08-19
Filing date: 2014-08-18
Publication date: 2015-02-26

Abstract

The present invention relates to an insulation sheet, a manufacturing method therefor, and an insulation panel, wherein the insulation sheet is implemented by applying a nanofiber web structure having phase change material particles so as to shield heat in the nanofiber web structure and to absorb heat from the phase change material particles, such that the insulation efficiency per unit area can be maximized since heat shielding and heat absorption can be carried out simultaneously.

Description

Insulation sheet, manufacturing method thereof and insulation panel using same

The present invention relates to a heat insulating sheet, and more particularly, a heat insulating sheet which can improve heat insulating efficiency by implementing a heat insulating sheet having a nanofiber web in which phase change material particles capable of absorbing heat are dispersed therein. And it relates to a manufacturing method and a heat insulating panel using the same.

Recently, energy-efficient eco-friendly industry has emerged, and various studies have been conducted to solve energy and environmental problems at the same time all over the world.

In particular, in terms of global warming, it is possible to reduce the amount of power consumed by the refrigerator, and various technologies are being developed for insulation to reduce energy in buildings.

Refrigerators consume high power consumption among household appliances, and reducing power consumption of the refrigerator is indispensable as a global warming measure. The power consumption of the refrigerator is largely determined by the heat insulating performance of the heat insulating material related to the efficiency of the cooling compressor and the amount of heat leakage.

Insulation materials for energy saving of buildings are traditionally used as heat insulating materials such as mineral wool and polyurethane. Recently, VIP (Vacuum Insulation Panel) and aerogels have attracted attention, and VIM (Vacuum Insulation Material) and DIM (Dynamic Insulation) Materials) are being researched as future technologies.

VIP and aerogels, which have very low thermal conductivity, can reduce energy consumption compared to conventional insulation materials, which can greatly increase the residential area. Especially, aerogels can be made of translucent and transparent materials, which can be applied to buildings. Very large.

Korean Laid-Open Patent Publication No. 10-2011-77859 includes a core portion including a core material; And a vacuum insulator having an outer covering covering the core portion, wherein the core portion is formed in a reduced pressure state, wherein the outer insulating material includes at least one nonwoven fabric layer. In this case, the core material of the vacuum insulator is glass fiber, polyurethane, polyester, polypropylene and polyethylene, but the pore size inside the glass fiber aggregate does not have a size suitable for trapping air, so the heat insulation effect is low. And, glass fiber has a complicated and difficult problem in the manufacturing process.

Korean Patent Laid-Open Publication No. 10-2011-15326 has been proposed as a core located inside the outer shell of the vacuum insulation material, wherein the cores of the vacuum insulation material are characterized in that the cores are bonded to each other by heat-sealing synthetic resin fibers, Since the fibers are thermally fused to each other by heating the ash fibers to a temperature of the melting point, there is a limit in improving the thermal insulation efficiency because the synthetic resin fibers become inorganic pores with almost no pores.

Therefore, the present inventors continue to research to improve the thermal insulation efficiency by deriving and inventing the structural features of the thermal insulation sheet that can maximize the thermal insulation efficiency, and at the same time save energy, eco-friendly, more economical, and available The present invention has been completed.

The present invention has been made in view of the problems of the prior art, the object of which consists of a nanofiber web is provided with a plurality of pores trapping the air to suppress the convection of the air is insulated, heat is applied to the nanofiber web An embodiment of the present invention provides a heat insulating sheet capable of improving heat insulation efficiency by implementing a heat insulating sheet containing phase-absorbing material particles that can be absorbed.

Another object of the present invention is to provide a heat insulating sheet and a method of manufacturing the same that can maximize the heat blocking efficiency in a structure capable of performing heat blocking and heat absorption at the same time.

Still another object of the present invention is to provide a heat insulation panel which can improve heat insulation properties by applying a heat insulation sheet capable of sequentially performing heat blocking and heat absorption as a core.

In order to achieve the above object, a hybrid insulating sheet according to an embodiment of the present invention, porous nanofiber web accumulated by the nanofibers having a microporous structure; And phase change material (PCM) particles dispersed in the nanofibers.

In addition, the manufacturing method of the insulating sheet for achieving the object of the present invention, the step of preparing a spinning solution by mixing a high thermal conductivity polymer material, phase change material particles and a solvent; And electrospinning the spinning solution to form a porous nanofiber web having a fine pore structure and in which phase change material particles are dispersed inside the nanofiber.

In addition, the heat insulation panel for achieving another object of the present invention, the outer space provided with an outer material; And an insulation sheet disposed inside the envelope to support the envelope, wherein the insulation sheet is a porous nanofiber web having a fine pore structure and in which phase change material particles are dispersed in the nanofiber. do.

As described above, in the present invention, by applying an insulating sheet including a nanofiber web containing the phase change material particles, the heat is blocked in the nanofiber web, and heat is applied to the phase change material particles included in the nanofiber web. By absorbing, heat shielding and heat absorption may be performed at the same time, thereby providing a thermal insulation technology capable of maximizing thermal insulation efficiency per unit area.

In the present invention, by adopting an insulating sheet of a nanofiber web in which the electrospun nanofibers are arranged in a three-dimensional network structure, a technique for improving thermal insulation performance by nano-sized micropores of a nanofiber web having a high thermal barrier ability is provided. Can provide.

In the present invention, the thermal insulation sheet is achieved by the lamination structure of the nanofiber web including the phase change material particles, or the lamination structure of the nanofiber web and the nonwoven fabric, thereby improving the strength, and simultaneously performing multiple heat shielding and heat absorption to insulate the insulation. It can provide a technique that can increase the.

In the present invention, by providing a vacuum insulation panel (Vacuum Insulation Panel, VIP) as a core of the insulation sheet embedded in the nanofiber web of the phase change material can provide a vacuum insulation technology that can maximize the insulation properties.

In the present invention, it is possible to provide an ultra-thin thermal insulation sheet and a thermal insulation panel by applying a nanofiber web, it is possible to provide a technology that can expand the internal space of the refrigerator and the building excellent in thermal insulation characteristics.

1 is a conceptual cross-sectional view for explaining an insulating sheet according to a first embodiment of the present invention,

2 is a conceptual view for explaining the nanofiber of the insulating sheet according to the first embodiment of the present invention,

3 is a conceptual cross-sectional view for explaining an insulating sheet according to a second embodiment of the present invention;

4 is a conceptual cross-sectional view for explaining an insulating sheet according to a third embodiment of the present invention;

5 is a conceptual cross-sectional view for explaining an insulating sheet according to a fourth embodiment of the present invention;

6a to 6c is a conceptual cross-sectional view for explaining an insulating sheet according to a fifth embodiment of the present invention,

7 is a conceptual cross-sectional view for explaining an insulating sheet according to a sixth embodiment of the present invention;

8 is a conceptual cross-sectional view for explaining an insulating sheet according to a seventh embodiment of the present invention;

9 is a conceptual cross-sectional view showing a vacuum insulation panel (Vacuum Insulation Panel, VIP) according to an embodiment of the present invention,

10 is a schematic cross-sectional view showing the electrospinning to form a nanofiber web applied to the heat insulating sheet according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings will be described in detail for the practice of the present invention.

In the following description, the phase change material (PCM) particles are contained in the nanofibers of the nanofiber web as an embodiment of the heat insulating sheet and the heat insulation panel according to the present invention, and transfer the transferred heat by blocking the nanofiber web. At the same time to reduce the amount of heat to be absorbed from the phase change material particles, to realize a structure that can maximize the thermal insulation efficiency.

The thermal insulation sheet and the thermal insulation panel of the present invention described below may be applied to refrigerators, buildings, and electronic devices, but the present invention is not limited thereto, and the same may be applied to thermal insulation materials used in other industrial fields.

In the present invention, by applying an insulating sheet containing a phase change material particle to the nanofiber web, the nanofiber web blocks heat and absorbs heat from the phase change material particles included in the nanofiber web. Therefore, the heat insulation sheet of the present invention can provide a heat insulation sheet that can perform heat shielding and heat absorption at the same time to maximize the heat insulation efficiency per unit area.

Nanofiber webs are arranged in a three-dimensional network structure with irregularly stacked electrospun nanofibers. The nanofibers form irregularly distributed nano-sized micropores in the nanofiber web, and the micropore increases the heat shielding ability of the nanofiber web, thereby providing excellent thermal insulation performance.

1 and 2, the insulating sheet 100 according to the first embodiment of the present invention is implemented as a web of nanofibers 100a containing the phase change material particles 121. At this time, the heat transferred to the thermal insulation sheet 100 is blocked at the nano-sized micropores of the nanofiber web, and absorbed by the phase change material particles 121 to improve the heat shielding efficiency.

The phase change material particle 121 absorbs heat transferred and has excellent heat blocking performance. That is, the phase change material particle 121 absorbs heat while changing from a solid phase to a liquid phase by endothermic reaction when heat is transferred. In addition, the phase change material particles 121 are changed into solid phases when the ambient temperature drops.

Referring to FIG. 3, nanofiber webs 115 containing no phase change material particles may be laminated on one or both surfaces of the nanofiber webs 105 containing phase change material particles, and thus may be implemented as a heat insulating sheet of a second embodiment. In this case, the nanofiber web 115 may serve as a support and a heat shield. Then, heat transferred to the heat insulating sheet of the second embodiment is first contacted and transferred to the nanofiber web 115 to block heat in the plurality of micropores. The amount of heat reduced by the amount of heat blocked in the micropores of the nanofiber web 115 is transferred to the nanofiber web 105 containing the phase change material particles. The nanofiber web 105 containing the phase change material particles can block heat in the micropores and at the same time absorb heat from the phase change material particles 121, thereby substantially increasing the thermal insulation efficiency of the thermal insulation sheet.

Referring to FIG. 4, the insulating sheet of the third embodiment has a structure in which a phase change material layer 120 is interposed between the first and

second nanofiber webs

110 and 130 containing phase change material particles. The heat transferred to the heat insulating sheet is primarily blocked by heat in the first nanofiber web 110 and absorbed heat, and heat is absorbed by the phase change material layer 120 to decrease heat by secondary. do. Therefore, the amount of heat delivered to the second nanofiber web 130 is further reduced. By heat shielding and heat absorption in the second nanofiber web 130, the thermal insulation sheet of the third embodiment is inevitably increased thermal insulation efficiency.

In the third embodiment, the spinning solution in which the polymer material, the phase change material particles and the solvent are mixed is spun to form the first nanofiber web 110, and the injection solution in which the phase change material particles and the solvent are mixed is sprayed to form the first nanofiber web 110. A phase change material layer 120 in which phase change material particles are dispersed in the nanofiber web 110 is formed. Subsequently, the second nanofiber web 130 is formed by surrounding the phase change material layer 120 and spinning the spinning solution in which the polymer material, the phase change material particles, and the solvent are mixed on the first nanofiber web 110. Prepare the sheet.

By stacking the second nanofiber web 130 in a state where the phase change material layer 120 is formed on the first nanofiber web 110 side, the insulating sheet of the fourth embodiment is structurally configured as the first and second nanofibers. The phase change material layer 120 is disposed at the interface of the

fibrous webs

110 and 130.

On the other hand, the nanofiber web is a spinning solution by mixing a polymer material and a solvent having a low thermal conductivity and a low thermal conductivity in a predetermined ratio to form a spinning solution, and the spinning solution is electrospun to form a nanofiber, and the nanofibers are accumulated It is formed in the form of a nanofiber web having pores.

In the present invention, spinning the spinning solution in which the polymer material, the phase change material particles and the solvent are mixed to form a nanofiber web containing the phase change material particles. At this time, the spun nanofibers include phase change material particles, and when the nanofibers are accumulated, a nanofiber web is formed. Phase change material particles are located inside the spun nanofibers. Here, the particle diameter of the phase change material particles is preferably smaller than the diameter of the nanofibers.

As the nanofibers have a smaller diameter, the specific surface area of the nanofibers increases, and the thermal barrier ability of the nanofiber web including a plurality of micropores increases, thereby improving thermal insulation performance.

The nanofibers have a diameter of, for example, 5 μm or less, preferably 1 μm or less, and the nanofiber web made of nanofibers traps air inside the micropores as it has a plurality of micropores, and traps the micropores. Condensation of trapped air is suppressed and heat transfer performance is excellent.

Fine pores formed in the nanofiber web is preferably set to several nm to 10um or less, preferably 5um or less, it can be implemented by adjusting the diameter of the nanofibers.

Here, the radiation method applied to the present invention is a general electrospinning, air electrospinning (AES: Air-Electrospinning), electrospray (electrospray), electrobrown spinning, centrifugal electrospinning Flash-electrospinning can be used.

In the present invention, for the purpose of improving the heat resistance of the nanofiber web of the insulating sheet obtained by electrospinning a low thermal conductivity and a mixture of a polymer having a high heat resistance alone or a mixture of a predetermined amount of a polymer having a low thermal conductivity and a high heat resistance polymer Nanofiber webs can be applied.

In this case, the polymer that can be used in the present invention is preferably dissolved in an organic solvent and capable of spinning and at the same time low in thermal conductivity, and more preferably in excellent heat resistance.

Polymers capable of spinning and low thermal conductivity are, for example, polyurethane (PU), polystyrene, polyvinylchloride, cellulose acetate, polyvinylidene fluoride (PVDF), polyacrylonitrile (PAN), polymethylmethacrylate. , Polyvinylacetate, polyvinyl alcohol, polyimide and the like.

In addition, the polymer having excellent heat resistance may be dissolved in an organic solvent for electrospinning and has a melting point of 180 ° C. or higher, for example, polyacrylonitrile (PAN), polyamide, polyimide, polyamideimide, poly ( Meta-phenylene isophthalamide), polysulfone, polyetherketone, polyethylene terephthalate, polytrimethylene terephthalate, polyethylene naphthalate, and aromatic polyesters such as polytetrafluoroethylene, polydiphenoxyphosphazene, poly Polyphosphazenes such as {bis [2- (2-methoxyethoxy) phosphazene]}, polyurethane copolymers including polyurethanes and polyetherurethanes, cellulose acetates, cellulose acetate butyrates, cellulose acetate propionates Etc. can be used.

The thermal conductivity of the polymer is preferably set to less than 0.1W / mK.

Polyurethane (PU) of the above polymers has a thermal conductivity of 0.016 to 0.040 W / mK, and polystyrene and polyvinyl chloride are known to have a thermal conductivity of 0.033 to 0.040 W / mK. The nanofiber web obtained by spinning them also has a low thermal conductivity. It will have thermal insulation properties.

The thickness of the nanofiber web may be set to 5um to 50um, preferably 10um to 30um.

In addition, the nanofiber web may be manufactured to have various thicknesses by laminating them in multiple layers. That is, the heat insulating sheet of the nanofiber web applied to the present invention can be manufactured in an ultra-thin structure and at the same time have a high heat insulating performance.

Solvents are dimethyl (dimethyl acetamide), DMF (N, N-dimethylformamide), NMP (N-methyl-2-pyrrolidinone), DMSO (dimethyl sulfoxide), THF (tetra-hydrofuran), DMAc (di-methylacetamide), EC ( At least one selected from the group consisting of ethylene carbonate, DEC (diethyl carbonate), DMC (dimethyl carbonate), EMC (ethyl methyl carbonate), PC (propylene carbonate), water, acetic acid and acetone can be used. have.

Since the nanofiber web is produced by the electrospinning method, the thickness is determined by the amount of spinning solution. Therefore, there is an advantage that it is easy to make the thickness of the nanofiber web to the desired thickness.

As such, since the nanofibers are formed in the form of nanofiber webs accumulated by the spinning method, the nanofibers may be formed in a form having a plurality of pores without a separate process, and the pore size may be adjusted according to the spinning amount of the spinning solution. Therefore, the nanofiber web can make a large number of pores in accordance with the spinning method is excellent in heat shielding performance and thus can improve the thermal insulation performance.

In the present invention, the inorganic particles which are heat insulating fillers for blocking heat transfer may be contained in the spinning solution for forming the nanofiber web. In this case, the nanofiber web of the nanofiber web may contain inorganic particles. The inorganic particles may be located inside the spun nanofibers or may be partially exposed to the nanofiber surface to block heat transfer. In addition, the inorganic particles may improve the strength of the nanofiber web with a heat insulating filler.

Preferably, the inorganic particles are SiO ₂ , SiON, Si ₃ N ₄ , HfO ₂ , ZrO ₂ , Al ₂ O ₃ , TiO ₂ , Ta ₂ O ₅ , MgO, Y ₂ O ₃ , BaTiO ₃ , ZrSiO ₄ , HfO One or more particles selected from the group consisting of ₂ or one or more particles selected from the group consisting of glass fibers, graphite, rock wool, and clay are preferred, but are not necessarily limited to these, alone or in combination of two or more. It can be included in the spinning solution.

In addition, a fumed silica may be included in the spinning solution for forming the nanofiber web.

5 is a conceptual cross-sectional view for explaining a heat insulating sheet according to a fourth embodiment of the present invention, and FIGS. 6A to 6C are conceptual cross-sectional views for explaining a heat insulating sheet according to a fifth embodiment of the present invention. 7 is a conceptual cross-sectional view for explaining a heat insulating sheet according to a sixth embodiment of the present invention, Figure 8 is a conceptual cross-sectional view for explaining a heat insulating sheet according to a seventh embodiment of the present invention.

In the fourth exemplary embodiment of the present invention, a non-woven fabric or a woven fabric may be combined with a nanofiber web containing phase change material particles to implement a high-strength insulating sheet. That is, in FIG. 5, the support 150 is composited on one surface or both surfaces of the nanofiber web 105 containing the phase change material particles. The nonwoven fabric or woven fabric may be formed as long as it can form a double structure with the nanofiber web, and the compounding method is not limited to special methods such as hot plate calendering, hot melt bonding, ultrasonic bonding, and laminating. What is necessary is just the method which can be compounded with a raw material.

In particular, nonwoven fabrics that can be used are commercially available two- or three-layered polyolefin-based porous membranes, such as PP / PE or PP / PE / PP membranes or single-layered PP or PE membranes, but the outer periphery of PP fibers as a core. It is also possible to use a nonwoven fabric made of double coated PP / PE fibers coated with PE, or a PET nonwoven fabric made of polyethylene terephthalate (PET) fibers.

In addition, in the fifth and sixth embodiments of the present invention, a nonwoven fabric containing phase change material particles in a fiber and a nanofiber web containing phase change material particles or a nanofiber web containing no phase change material particles are combined. By increasing the strength, it is possible to implement a heat insulating sheet capable of multi-stage heat blocking and heat absorption. Since the manufacturing method of the nonwoven fabric is already known, a detailed description thereof will be omitted.

Here, the nonwoven fabric is defined as having a fabric shape in which the fiber aggregates are bonded to each other by chemical or mechanical action or appropriate moisture and heat treatment without a process of spinning, weaving, and knitting, and are composed of fiber aggregates using short fibers or filament fibers. The thin sheet of the web is manufactured to form stability by the method of bonding the fibers themselves without the spinning process which is a yarn forming process.

The nonwoven fabric can be made of any fibrous material. In particular, the nonwoven fabric can be made of natural fibers, synthetic fibers, glass fibers, and carbon fibers. Nonwoven fabrics can be produced using short fibers with lengths of several millimeters to hundreds of millimeters and long fibers with infinite lengths.

Insulating sheet of the fifth embodiment, first, the phase change material particles on one side (FIG. 6A), or both sides (FIG. 6B) of the nonwoven fabric 200 having fibers containing the phase change material particles and having a predetermined porosity. It can be implemented in a structure that forms the nanofiber web (101,102) that does not contain. In addition, the insulating sheet may be implemented with a structure in which nanofiber

webs

110 and 130 containing phase change material particles are formed on one surface or both surfaces of the nonwoven fabric 200 (FIG. 6C).

Here, the fiber diameter of the nonwoven fabric 200 is larger than the fiber diameter of the

nanofiber webs

101 and 102, and the nanofibers are directly spun or compounded on the nonwoven fabric 200 to implement the heat insulating sheet of the fifth embodiment.

In addition, as shown in Figure 7, the insulating sheet of the sixth embodiment in which the non-woven fabric 210 having a fiber containing the phase change material particles is laminated on the nanofiber web 110 of the insulating sheet structure of Figure 6c Can be implemented.

Referring to FIG. 8, the inorganic porous film 250 may be laminated or covered on part or all of the outer circumferential surface of the insulating sheet 100 of the above-described embodiment. The non-porous film 250 serves to block the heat transmitted to the heat insulation sheet 100 first.

The inorganic porous film 250 is preferably applied as an inorganic porous polymer film made of a polymer material, and the inorganic porous polymer film may be formed using a nanofiber web for film made of nanofibers by electrospinning a spinning solution in which a polymer material and a solvent are mixed. It is possible to produce a polymer film of inorganic pores by forming and calendering or heat-treating the nanofiber web for film at a temperature lower than the melting point of the polymer (eg PVDF). Here, in the heat treatment process, the heat treatment temperature may be performed at a temperature slightly lower than the melting point of the polymer because the solvent remains in the nanofiber web, and the inorganic fiber film is formed to prevent the nanofiber web from completely melting by the heat treatment. To do this.

Since the heat insulating sheet of the above-described embodiments is provided with a flexible nanofiber web, a folded structure in a plate shape is possible due to excellent bendability.

The present invention may further include at least one reinforcing sheet hybridized to one surface, both surfaces, and the entirety of the heat insulating sheets according to the first to seventh embodiments described above. Here, hybridization means a bonding relationship of adhesion, adhesion, lamination, contact, fixing, and the like.

The reinforcing sheet may be a heat insulating member or a heat radiating member, and the heat insulating sheet and the reinforcing sheet may be bonded to each other by an adhesive interposed between the heat insulating sheet and the reinforcing sheet.

In this case, the adhesive may be any of acrylic, epoxy, aramid, urethane, polyamide, polyethylene, EVA, polyester, and PVC. One adhesive, hot melt web and hot melt powder having a plurality of pores formed by accumulation of heat-adhesive fibers may be one.

In addition, the adhesive may include a conductive filler for thermal diffusion having an aspect ratio of 1: 100 and a conductive filler for heat transfer in a spherical shape.

9 is a conceptual cross-sectional view showing a vacuum insulation panel (VIP) according to an embodiment of the present invention.

The above-described insulation sheet may be embedded inside the insulation panel to exhibit insulation performance. In the following description, a vacuum insulation panel is mainly exemplified as a kind of insulation panel, but is not limited thereto, and an insulation panel structure in which an internal space is not vacuumed or reduced in pressure is also included in the present invention.

Referring to FIG. 9, the vacuum insulation panel 300 according to an embodiment of the present invention has a gas barrier property, and preferably includes an outer shell material 310 and an outer shell material 310, which form a predetermined decompression space therein. It is disposed to include an insulating sheet 100 for supporting the outer shell material 310.

Since the insulation sheet 100 applied as the core to the vacuum insulation panel 300 includes a porous nanofiber web, the insulation sheet 100 includes a plurality of micropores that can trap air, and the air trapped in the micropores falls out by itself. Since it is difficult to exit, the outer shell material 310 exhibits excellent thermal insulation performance even when the inside of the outer shell material 310 is not a vacuum or a reduced pressure space. Therefore, there are many advantages when applied as a building insulation.

Here, the decompression space means a space where the pressure inside the pressure is reduced to be lower than the atmospheric pressure.

In addition, in the vacuum insulation panel 300 according to an embodiment of the present invention, when the inside of the envelope 310 is made of a vacuum or reduced pressure space, the inside of the envelope 310 or the insulation sheet 100 may be moisture or gas. It may be configured to include a getter material (not shown) for adsorbing. The getter material may include, for example, an absorbent and a gas absorbent in powder form, and may be made of PP or PE nonwoven fabric.

In addition, the getter material preferably includes at least one selected from the group consisting of silica gel, zeolite, activated carbon, zirconium, barium compound, lithium compound, magnesium compound, calcium compound and quicklime.

The type of getter material that can be used in the present invention is not particularly limited, and materials commonly used in the field of manufacturing vacuum insulators can be used.

In addition, the outer cover material 310 serves to cover the heat insulating sheet 100 as a core and to maintain the inside of the core under reduced pressure or vacuum. The outer shell material 310 is formed in an envelope in advance, and after the insulating sheet 100 is inserted, sealing is performed by thermo-compressing the inlet portion in a vacuum atmosphere. Accordingly, the envelope 310 is used after sealing the outer portions of three sides of the upper envelope 310a and the lower envelope 310b having a quadrangular shape first to form an envelope.

The kind of the outer cover material 310 that can be used in the present invention is not particularly limited, and a material commonly used in the field of manufacturing a vacuum insulator may be used. The envelope material 310 used in the present invention may include, for example, a sealing layer surrounding the heat insulation sheet 100; A barrier layer surrounding the sealing layer; And a nonwoven fabric layer or a protective layer surrounding the barrier layer.

As described above, the sealing layer coats the built-in insulation sheet 100 as the sealing (compression) is made by thermocompression bonding, and adheres to the core to maintain the panel form. The material of the sealing layer that can be used in the present invention is not particularly limited and the film can be bonded by thermocompression bonding. For example, the thermocompression layer is a linear low density polyethylene (LLDPE), low density polyethylene (LDPE), ultra low density Polyolefin resins such as polyethylene (VLDPE) and high density polyethylene (HDPE), and thermocompression bonding such as polypropylene (PP), polyacrylonitrile film, polyethylene terephthalate film, or ethylene-vinyl alcohol copolymer film, in addition to the above resins Possible resins, or mixtures thereof.

The barrier layer surrounds the sealing layer, maintains the degree of vacuum inside, and serves to block external gas and water vapor. In the present invention, the material of the barrier layer is not particularly limited, and a laminated film (deposited film film) or the like on which metal is deposited on a metal foil or a resin film may be used. As the metal, aluminum, copper, stainless steel, or iron may be used, but is not limited thereto.

In addition, the deposited film may be formed by depositing a metal such as aluminum, stainless steel, cobalt or nickel, silica, alumina, or carbon by a deposition method or a sputtering method, and the resin film serving as a substrate. As the general resin film used in the art can be used. In the present invention, it is preferable to use an aluminum deposition film or aluminum foil as the barrier layer.

In addition, the nonwoven layer surrounds the barrier layer and serves as a protective layer that primarily protects the vacuum insulation from external shock. In addition, the nonwoven fabric layer can solve the problem that the thermal performance of the heat insulating material is lowered by the high thermal conductivity of the barrier layer. The material of the nonwoven fabric layer may be PP, PTFE.

In addition, instead of the nonwoven fabric layer, a protective layer consisting of one or two layers may be used to protect the barrier layer. This protective layer may be made of one or more resins selected from the group consisting of polyamide, polypropylene, polyethylene terephthalate, polyacrylonitrile, polyvinyl alcohol, nylon, PET, K-PET and ethylene vinyl alcohol.

Referring to FIG. 10, the electrospinning apparatus includes a stirrer (2) using a mixing motor (2a) using pneumatic pressure as a driving source to prevent phase separation until polymer particles having low thermal conductivity, phase change material particles, and a solvent are mixed and radiated. It includes a mixing tank (Mixing Tank) (1) and a plurality of spinning nozzle (4) connected to a high voltage generator. The polymer solution discharged from the mixing tank 1 to a plurality of spinning nozzles 4 connected through a metering pump (not shown) and a transfer pipe 3 is passed through the spinning nozzles 4 charged by a high voltage generator, 5) nanofibers 5 accumulate on a grounded collector 6 in the form of a conveyor which is discharged at a constant speed and moves at a constant speed to form a porous nanofiber web 7.

That is, in the present invention, the spinning solution is prepared by mixing a polymer material having low thermal conductivity, particles of a phase change material, and a solvent, and then electrospinning the spinning solution to form a porous nanofiber web having a fine pore structure. The particles form a nanofiber web in which the nanofibers are dispersed.

In general, when a multi-hole spin pack (for example, 245 mm / 61 holes) is applied for mass production, mutual interference occurs between the multi-holes, so that the fibers are blown off and blocking is not achieved. As a result, the separator obtained by using a multi-hole spinning pack becomes too bulky, making it difficult to form the separator, and acts as a trouble source of radiation.

In consideration of this, in the present invention, as shown in FIG. 10, the porous nanofiber web is an air electrospinning method in which an air 4a is injected to each spinning nozzle 4 using a multi-hole spinning pack. (7) is produced.

That is, in the present invention, when the electrospinning is made by air electrospinning, the air is sprayed from the outer circumference of the spinning nozzle to play a dominant role in blocking and accumulating the air made of a polymer having high volatile polymer. This high nanofiber web can be produced, minimizing the radiation problems that can occur as the fibers fly around.

In the present invention, when a high thermal conductivity polymer material and a heat resistant polymer material are mixed and spun, it is preferable to prepare a mixed spinning solution by adding to a two-component solvent.

The obtained porous nanofiber web 7 is then calendered at a temperature below the melting point of the polymer in the calender device 9 to obtain a thin nanofiber web 10 used as a core material.

In the present invention, the porous nanofiber web 7 obtained as described above remains on the surface of the nanofiber web 7 while passing through a pre-air dry zone by the preheater 8. It is also possible to go through a calendaring process after adjusting the amount of solvent and water.

Pre-Air Dry Zone by Preheater (8) is applied to the web by using a fan of 20 ~ 40 ℃ air and the solvent remaining on the surface of the nanofiber web (7) By controlling the amount of water to control the bulk of the nanofiber web 7 (bulky) to increase the strength of the membrane and at the same time it is possible to control the porosity (Porosity).

In this case, if calendering is performed in a state in which the volatilization of the solvent is excessive, the porosity increases but the strength of the nanofiber web is weakened. On the contrary, when the volatilization of the solvent is reduced, the nanofiber web melts.

The method of forming the porous nanofiber web 10 by using the electrospinning device of FIG. 10 is a spinning solution by first dissolving a polymer material having a low thermal conductivity alone or a mixture of a polymer material having a low thermal conductivity and a heat resistant polymer material in a solvent. Prepare. In this case, in order to reinforce heat resistance, a predetermined amount of inorganic particles may be added to the spinning solution. In addition, when the nanofiber web is formed using a polymer material having low thermal conductivity and excellent heat resistance, for example, polyurethane (PU), it has both thermal insulation and heat resistance.

Thereafter, the spinning solution is directly spun onto the collector 6 using an electrospinning device or spun onto a porous substrate such as a nonwoven fabric so as to form a porous nanofiber web 10 having a single layer structure or a multilayer composed of a porous nanofiber web and a porous substrate. Fabricate a nanofiber web sheet of structure.

Subsequently, in the case where the obtained nanofiber web sheet is wide, it is cut into a desired width, and then it is folded into a plate shape several times or wound into a plate shape by a winding machine to have a desired thickness, or a plurality of core sheets are cut into a desired shape. It is then laminated in multiple layers. In addition, after laminating in multiple layers, it can be cut into a desired shape.

It is desirable to increase the lamination density by hot or cold pressing a plurality of laminated nanofiber web sheets as needed.

In the present invention, after producing a large-area nanofiber web sheet, it is also possible to cut and use in a predetermined shape depending on the purpose of use, such as heat insulating material for construction or refrigerator.

Meanwhile, in the present invention, when forming a nanofiber web, porous nanofibers by spinning a spinning solution on a transfer sheet made of one of a nonwoven fabric and a polyolefin-based film made of paper, a polymer material which is not dissolved by a solvent contained in a spinning solution. After the web is formed, the nanofiber web sheet can be produced by laminating with the nonwoven fabric while separating the nanofiber web from the transfer sheet, and the obtained sheet can be laminated in multiple stages. By producing a nanofiber web using the transfer sheet described above it is possible to improve the productivity in the mass production process.

In the above, the present invention has been illustrated and described with reference to specific preferred embodiments, but the present invention is not limited to the above-described embodiments, and the present invention is not limited to the spirit of the present invention. Various changes and modifications will be possible by those who have the same.

The present invention blocks the heat in the nanofiber web, absorbs heat from the particles of the phase change material included in the nanofiber web, and at the same time perform heat blocking and heat absorption to provide an insulating sheet that can maximize the thermal insulation efficiency per unit area to provide.

Claims

Porous nanofiber webs accumulated by the nanofibers and having a microporous structure; And

Thermal insulation sheet comprising a phase change material (PCM) particles dispersed in the nanofibers.
The heat insulating sheet of claim 1, further comprising nanofiber webs laminated on one or both surfaces of the nanofiber webs.
The heat insulating sheet according to claim 1, further comprising a nonwoven fabric or a woven fabric composited with the nanofiber web.
The heat insulating sheet according to claim 1, further comprising a nonwoven fabric laminated on the nanofiber web and having fibers containing phase change material particles and having a predetermined porosity.
The heat insulating sheet according to claim 4, wherein the fiber is one of natural fiber, synthetic fiber, glass fiber, and carbon fiber.
The method of claim 4, wherein the nanofiber web is laminated on one surface of the nonwoven fabric,

The insulating sheet further comprises a porous nanofiber web laminated on the other surface of the nonwoven fabric, having a microporous structure, and in which phase change material particles are dispersed inside the nanofiber.
The heat insulating sheet of claim 1, further comprising inorganic particles in the nanofibers.
The method of claim 7, wherein the inorganic particles are SiO 2 , SiON, Si 3 N 4 , HfO 2 , ZrO 2 , Al 2 O 3 , TiO 2 , Ta 2 O 5 , MgO, Y 2 O 3 , BaTiO 3 , ZrSiO 4 , at least one particle selected from the group consisting of HfO 2 or at least one particle selected from the group consisting of glass fibers, graphite, rock wool, and clay.
The heat insulating sheet of claim 1, wherein the nanofibers are made of a polymer having low thermal conductivity.
The heat insulation sheet of Claim 1 whose diameter of the said nanofiber is 1 micrometer or less.
The insulating sheet according to claim 1, further comprising an inorganic porous film or a reinforcing sheet laminated on part or all of an outer circumferential surface of the insulating sheet.
The heat insulating sheet according to claim 11, wherein the reinforcing sheet is a heat insulating member or a heat radiating member.
Preparing a spinning solution by mixing a polymer material having low thermal conductivity, particles of a phase change material, and a solvent; And

Electrospinning the spinning solution to form a porous nanofiber web having a fine pore structure and having phase change material particles dispersed inside the nanofiber;
An outer shell material having an inner space; And

A heat insulation sheet disposed inside the shell material to support the shell material,

The heat insulation sheet,

An insulation panel having a microporous structure and a porous nanofiber web in which phase change material particles are dispersed inside a nanofiber.
15. The thermal insulation panel according to claim 14, further comprising a nonwoven fabric having fibers containing phase change material particles, having a predetermined porosity, and laminated to the nanofiber web.
The heat insulation panel according to claim 14, wherein the nanofibers are made of a polymer having a thermal conductivity of less than 0.1 W / mK.
The heat insulation panel according to claim 14, further comprising an inorganic porous film or a reinforcement sheet laminated on part or all of an outer circumferential surface of the heat insulation sheet.
15. The thermal insulation panel according to claim 14, wherein the envelope is made of a metallic material.
The heat insulation panel according to claim 14, wherein the inner space of the envelope material is vacuum or depressurized.