KR20150047759A - Hybrid Heat Insulation Sheet and Manufacturing Method thereof - Google Patents

Abstract

The present invention relates to a hybrid heat insulation sheet and a manufacturing method thereof. The present invention includes: a heat spreader which distributes heat which is transmitted; a bonding sheet which is bonded to the heat spreader and has a pattern shape with a plurality of opening parts; a heat delay unit which temporally delays and conducts the heat distributed from the heat spreader and is filled in the opening parts; and an insulation unit which is bonded to the bonding sheet, collects the heat which is temporally delayed and conducted, and insulates the collected heat.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a hybrid thermal insulation sheet,

The present invention relates to a heat insulating sheet, and more particularly, to a heat insulating sheet having a plurality of openings in which a phase change material is constrained so as to prevent external leakage of a phase change material phase- And a method for manufacturing the hybrid heat-insulating sheet capable of maximizing the heat insulation efficiency by sequentially advancing heat dispersion, heat delay, and heat insulation by interposing between the heat insulation portions.

2. Description of the Related Art In recent years, electronic products including portable terminals have been continuously developed, and electronic products have been promoted in terms of high performance and versatility according to the needs of users.

Particularly, in order to maximize the portability and convenience of users, miniaturization and weight reduction are indispensable for a portable terminal, and components integrated in smaller and smaller spaces are mounted for high performance. Accordingly, the parts used in the portable terminal have higher performance and higher heat generation temperature, and the increased heat generation temperature affects the adjacent components, thereby causing a problem of deteriorating the performance of the portable terminal.

Various heat insulating materials have been applied to portable terminals in order to solve the problem by such heat generation. However, various researches and technologies have been developed for insulation since an optimal heat insulating material having a thin thickness and excellent heat insulating performance has not been developed.

Korean Patent Publication No. 10-1134880 discloses a portable terminal having a heat insulating film including a heat insulating film disposed on the front surface of an LCD, and heat generated from the portable terminal is transmitted to the user's face through an LCD There is an advantage that it can be prevented. However, such a heat insulating film is not specific in its constitution, and its heat insulating performance can not be known, and there is a problem that a heat problem generated in a recent high performance portable terminal can not be solved.

Therefore, the inventors of the present invention have continued to study insulation technology capable of being slim and capable of excelling in heat insulation performance, thereby deriving the structural characteristics of a heat-insulating sheet capable of successively performing heat dispersion, heat delay, and insulation By inventing, we have completed the present invention which is more economical, usable and competitive.

Korean Patent Registration No. 10-1134880

SUMMARY OF THE INVENTION The present invention has been made in view of the problems of the prior art, and it is an object of the present invention to provide a heat spreader and an adiabatic portion, in which an adhesive sheet having a plurality of openings, And to provide a hybrid thermal insulation sheet capable of preventing external leakage of a changing substance and a method of manufacturing the same.

Another object of the present invention is to provide a hybrid thermal insulation sheet capable of maximizing heat insulation efficiency by hybridizing a multi-functional structure capable of blocking heat, and a method of manufacturing the same.

Another object of the present invention is to provide an ultra-thin and ultra-slim hybrid heat-insulating sheet and a method of manufacturing the same, by applying a structure capable of sequentially carrying out heat dispersion, thermal delay and insulation.

It is still another object of the present invention to provide a nanofiber web in which a nanofiber web arranged in a three-dimensional network structure is included in a heat insulating sheet, An insulating sheet and a method of manufacturing the same.

In order to achieve the above-mentioned object, an embodiment of the present invention is a heat spreader for dispersing heat transferred thereto; An adhesive sheet adhered to the heat spreader and having a pattern shape having a plurality of openings; A heat spread edge filled in the plurality of openings, the heat spreading device delaying the heat dispersed in the heat spreader in time and conducting the heat; And a heat insulating portion adhered to the adhesive sheet and collecting the heat transferred by time delay in the heat paper edge portion to insulate the heat.

According to another embodiment of the present invention, there is provided a method of manufacturing a heat spreader, comprising: bonding an adhesive sheet to a heat spreader; Patterning the adhesive sheet to form a patterned adhesive sheet having a plurality of openings; Filling a plurality of openings of the patterned adhesive sheet with a powder of phase change material; Placing the heat spreader on a hot plate and making powder of the phase change material into a liquid phase change material at a temperature of the hot plate; Releasing the heat spreader from the hot plate to phase-change the liquid phase-change material into a film phase-change material in a solid state; And adhering an adiabatic portion to the patterned adhesive sheet. The present invention also provides a method for manufacturing a hybrid thermal insulation sheet.

As described above, in the present invention, after the adhesive sheet having a plurality of openings is adhered to the heat spreader, the phase change material is restrained inside the opening, thereby preventing external leakage of the phase change material that is phase- There is an effect that can be done.

In the present invention, a hybrid insulation sheet having a multi-layered structure in which a structure for dispersing heat generated from an exothermic component, a structure for delaying dispersed heat in time, and a structure for trapping heat to heat- There is an advantage that can be made.

The present invention adopts a heat insulating sheet of a nanofiber web in which electrospun nanofibers are arranged in a three-dimensional network structure to improve heat insulation performance by using three-dimensional nano-sized micropores of a nanofiber web having a large heat collecting ability Technology can be provided.

In the present invention, the heat insulating sheet including the phase change material capable of delaying the heat conduction time is advantageously hybridized with the sheet capable of dispersing and insulating heat, thereby improving the heat blocking efficiency.

According to the present invention, heat dissipation, thermal delay, and heat insulation can be performed successively. Thus, the heat insulating performance can be improved and the product can be mounted on a high-performance electronic product. At the same time, the thickness of the three-layer structure can be reduced, The present invention can be applied to electronic products including portable terminals.

1 is a schematic cross-sectional view of a hybrid thermal insulation sheet according to a first embodiment of the present invention,
FIGS. 2A to 2E are schematic cross-sectional views illustrating a method for manufacturing a hybrid thermal insulation sheet according to a first embodiment of the present invention,
FIGS. 3A and 3B are schematic cross-sectional views for explaining a modification of some steps of the method for manufacturing a hybrid thermal insulation sheet according to the first embodiment of the present invention;
4 is a conceptual sectional view for explaining a hybrid thermal insulation sheet according to a second embodiment of the present invention,
5A and 5B are conceptual sectional views illustrating a laminated structure of a nanofiber web and a nonwoven fabric applied as a heat insulating portion of a hybrid thermal insulation sheet according to the first and second embodiments of the present invention,
6 is a conceptual sectional view for explaining the heat flow in the hybrid thermal insulation sheet according to the first and second embodiments of the present invention,
7 is a schematic cross-sectional view showing an electrospinning apparatus for forming a nanofiber web applied to the hybrid thermal insulation sheet according to the first and second embodiments of the present invention.

The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms and the inventor may appropriately define the concept of the term in order to best describe its invention It should be construed as meaning and concept consistent with the technical idea of the present invention.

Therefore, the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not represent all the technical ideas of the present invention. Therefore, It is to be understood that equivalents and modifications are possible.

Hereinafter, the present invention will be described in more detail with reference to the drawings.

The hybrid heat-insulating sheet of the present invention to be described later can be applied to a portable terminal, a refrigerator, and a building, but the present invention is not limited thereto and can be similarly applied to a heat insulation material used in other industrial fields.

FIG. 1 is a schematic cross-sectional view of a hybrid thermal insulation sheet according to a first embodiment of the present invention, and FIGS. 2A to 2E are schematic cross-sectional views illustrating a method of manufacturing a hybrid thermal insulation sheet according to a first embodiment of the present invention And FIGS. 3A and 3B are schematic cross-sectional views for explaining a modification of some processes of the method for manufacturing a hybrid thermal insulation sheet according to the first embodiment of the present invention.

The hybrid heat insulating sheet according to the first embodiment of the present invention includes a heat spreader, a heat spread edge, and a heat insulating portion, as described later.

Referring to FIG. 1, a preferred structure of the hybrid thermal insulation sheet according to the first embodiment of the present invention will be described. The heat spreader 210 disperses the heat transferred. An adhesive sheet 211a adhered to the heat spreader 210 and having a pattern shape having a plurality of openings; A heat spread edge 215 filled with the plurality of openings, the heat spreader 210 delaying and conducting heat dispersed in the heat spreader 210; And a heat insulating part 217 adhered to the adhesive sheet 211a and collecting the heat transferred by the heat-pervious edge 215 with time delay to insulate the heat.

Here, it is preferable that the heat spreader 210 is a plate of Cu material, the heat-softened portion 215 is a film of a phase change material, and the heat insulating portion 217 is a nanofiber web.

As described above, the hybrid thermal insulation sheet according to the first embodiment of the present invention disperses the heat conducted by the heat spreader 210, conducts heat to the heat insulating portion 217 by delaying the heat in the heat spreading portion 215 in time, By collecting the heat conducted by the heat insulating portion 217 and cutting off the heat, the heat insulating efficiency can be maximized.

2A to 2E, a method of manufacturing a hybrid thermal insulation sheet according to a first embodiment of the present invention includes adhering an adhesive sheet 211 to a heat spreader 210 (FIG. 2A) And patterned to form a patterned adhesive sheet 211a having a plurality of openings 211b (Fig. 2B). Here, instead of the processes of FIGS. 2A and 2B, the patterned adhesive sheet 211a having a plurality of openings 211b may be directly bonded to the heat spreader 210. FIG.

2C). Then, the heat spreader 210 is attached to the hot plate 220, and then the heat spreader 210 is heated to a predetermined temperature And the powder 212 of the phase change material is made into a phase change material 213 in a liquid state at the temperature of the hot plate 220 (FIG. 2d). Then, the heat spreader 210 is detached from the hot plate 220 to form a film of phase change material 215a. Here, the liquid phase material 213 is phase-changed to a solid state film-form phase-change material 215a at about room temperature. Subsequently, the heat insulating portion 217 is bonded to the patterned adhesive sheet 211a.

In the present invention, the release sheet is adhered to one side of the adhesive sheet 211 and the heat spreader 210 is adhered to the other side of the adhesive sheet 211 by adhering the adhesive sheet 211 to which the releasing paper is adhered to the heat spreader 210 The release paper 219 and the adhesive sheet 211 are patterned to form a patterned release paper 219 and an adhesive sheet 211a each having a plurality of openings 219a and 211b as shown in FIG. 3B) is filled with a powder 212 of a phase change material which is a heat delayer in the plurality of openings 219a and 211b of the patterned release paper 219 and the adhesive sheet 211a, It is possible to perform a process of phase-changing the film from the plate to a phase-change material in the form of a film.

That is, in the present invention, the processes of FIGS. 3A and 3B can be performed instead of the processes of FIGS. 2A to 2C. 3B, the powder 212 of phase change material may be filled in both the patterned release paper 219 and both of the plurality of openings 219a, 211b of the adhesive sheet 211a.

Accordingly, the hybrid thermal insulation sheet according to the first embodiment of the present invention is characterized in that a plurality of openings 211b of the adhesive sheet 211a bonded to the heat spreader 210 are filled with a powder 212 of phase change material, And the phase change material is film-formed by sequentially changing the powder 212 of the phase change material into a liquid state and a solid state so that the phase change material is restrained by the heat transferred by being constrained to the plurality of openings 211b of the adhesive sheet 211a When the phase change material is phase-changed by the endothermic reaction, it can be prevented from leaking to the outside.

FIG. 4 is a conceptual cross-sectional view for explaining a hybrid insulation sheet according to a second embodiment of the present invention, and FIGS. 5A and 5B are a cross-sectional view of a hybrid insulation sheet according to the first and second embodiments of the present invention, Sectional view illustrating a laminated structure of a nanofiber web and a nonwoven fabric.

Referring to FIG. 4, the hybrid thermal insulation sheet 100 according to an embodiment of the present invention includes a heat spreader 110, a heat spreader 120, and a heat insulating portion 130.

The heat spreader 110, the heat spread zone 120, and the heat insulating portion 130 are sequentially laminated so that the hybrid heat insulating sheet 100 has a three-layer structure.

The heat spreader 110 disperses heat transmitted from the outside. That is, the heat spreader 110 functions to dissipate heat by preventing the heat generated from the heat generating component from concentrating in one place. The heat spreader 110 is preferably made of a copper material or an aluminum material which has a high thermal conductivity and is inexpensive and can perform nickel plating on the heat spreader 110 of copper material to solve oxidation and corrosion problems have. It is preferable that the thickness of the heat spreader 110 is 10 占 퐉 to 40 占 퐉.

The thermal padding 120 temporally delays the heat dissipated in the heat spreader 110 from being conducted to the heat insulating portion 130. It is preferable that the heat spreading edge portion 120 includes a phase change material (PCM). The phase change material absorbs the transmitted heat and delays heat conduction. That is, the phase-change material absorbs heat as it changes from a solid phase to a liquid phase by endothermic reaction when heat is transferred. And the phase change material changes back to a solid phase when the ambient temperature falls.

A method of manufacturing an example of the heat-softening edge 120 will be described. First, a phase-change material is powdered and then mixed with a phase change material powder, a binder, and a solvent to prepare a slurry in which powder of the phase- The slurry is made into a film to produce a film in which the powder of the phase change material is dispersed, and this is applied to the heat spread edge 120.

Another example of the method of manufacturing the thermally fringed portion 120 includes placing a heat spreader 110 on a hot plate and applying a powder of phase change material on the heat spreader 110 to change the temperature of the hot plate For example, when the heat spreader 110 is detached from the hot plate after making the phase change material powder into a liquid state at about 65 ° C, the phase change material becomes a film form. It is preferable that the thickness of the thermally fringed portion 120 is 10 占 퐉 to 30 占 퐉.

The heat insulating part (130) collects the heat conducted in the heat spreading part (120) to block heat. At this time, it is preferable that the heat insulating part 130 is integrated by a nanofiber and applied as a nanofiber web having a three-dimensional micropore structure. The thickness of the heat insulating portion 130 is preferably 10 占 퐉 to 30 占 퐉.

As described above, the hybrid thermal insulation sheet 100 according to an embodiment of the present invention can perform heat dispersion, heat delay, and heat insulation sequentially, and thus can be applied to a high performance portable terminal with excellent heat insulation performance. At the same time, The thickness of the three-layer structure can be thinned, so that it can be adopted for ultra-thin and ultra-slim portable terminals.

In addition, nanofiber webs are randomly stacked with electrospun nanofibers arranged in a three-dimensional network structure. The nanofibers result in the formation of irregularly distributed three-dimensional micropores in the nanofiber web, and the ability of the nanofiber web to collect heat by the three-dimensional micropores, resulting in excellent thermal insulation performance.

On the other hand, a nanofiber web is produced by preparing a spinning solution by mixing a polymer material having a low thermal conductivity and a solvent at a certain ratio, spinning the spinning solution to form nanofiber, And is formed in the form of a nano web having pores.

As the diameter of the nanofibers is smaller, the specific surface area of the nanofibers is increased and the heat collecting ability of the nanofiber web having a plurality of micropores is increased, thereby improving the heat insulating performance.

The nanofibers have a diameter of, for example, 1 .mu.m or less, and the nanofibers made of nanofibers have a plurality of micropores having a three-dimensional structure, thereby trapping and trapping air in the micropores.

The micropores formed in the nano-web are preferably set to 4 nm to 1 μm or less, and may be implemented by controlling the diameter of the nanofibers.

Here, the spinning method applied to the present invention is a spinning method using general electrospinning, air-electrospinning (AES), electrospray, electrobrown spinning, centrifugal electrospinning, , And flash-electrospinning may be used.

For the purpose of improving the heat resistance of a nanofiber web of a hybrid thermal insulation sheet, a mixed polymer having a low thermal conductivity and excellent heat resistance, or a mixture of a polymer having a low thermal conductivity and a polymer having a high heat resistance, The obtained nano-web can be applied.

At this time, the polymer which can be used in the present invention is preferably dissolved in an organic solvent to be spinnable and low in thermal conductivity, and more preferably excellent in heat resistance.

Polymers that are capable of radiation and have low thermal conductivity include, for example, polyurethane (PU), polystyrene, polyvinyl chloride, cellulose acetate, polyvinylidene fluoride (PVDF), polyacrylonitrile , Polyvinyl acetate, polyvinyl alcohol, polyimide, and the like.

The polymer having excellent heat resistance is a resin which can be dissolved in an organic solvent for electrospinning and has a melting point of 180 ° C or higher. Examples of the resin include polyacrylonitrile (PAN), polyamide, polyimide, polyamideimide, poly Aromatic polyesters such as polyethylene terephthalate, polyethylene terephthalate, polyethylene terephthalate, and the like, polytetrafluoroethylene, polydiphenoxaphospazene, poly (ethylene terephthalate), poly Polyphosphazenes such as bis [2- (2-methoxyethoxy) phosphazene], polyurethane copolymers including polyurethane and polyether urethane, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate Etc. may be used.

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

Among the above polymers, polyurethane (PU) has a thermal conductivity of 0.016 to 0.040 W / mK, polystyrene and polyvinyl chloride have a thermal conductivity of 0.033 to 0.040 W / mK, and the nanoweb obtained by spinning the polystyrene and polyvinyl chloride also has a low thermal conductivity.

In addition, the nano web can be manufactured to have various thicknesses by stacking the nano webs in multiple layers. That is, the heat insulating sheet of the nanofiber web applied to the present invention can have a high heat insulating performance while being manufactured in an ultra thin structure.

The solvent is selected from the group consisting of DMA (dimethyl acetamide), N, N-dimethylformamide, N-methyl-2-pyrrolidinone, DMSO, THF, DMAc, ethylene carbonate, DEC, dimethyl carbonate, ethyl methyl carbonate, propylene carbonate, water, acetic acid, and acetone. .

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

As described above, since the nanofibers are formed by the nanofiber web in which the nanofibers are accumulated by the spinning method, they can be formed into a plurality of pores without any additional process, and the size of the pores can be controlled according to the spinning amount of the spinning solution. Therefore, it is possible to finely form a large number of pores, so that the heat shielding performance is excellent and the heat insulating performance can be improved accordingly.

In the present invention, the spinning liquid for forming the nanofiber web may contain inorganic particles, which are heat insulating fillers for blocking heat transfer. In this case, the nanofibers of the nanofiber web may contain inorganic particles. The inorganic particles are located inside the radiated nanofiber, or are partially exposed to the surface of the nanofiber to block heat transfer. Further, the inorganic particles can improve the strength of the nanofiber web with an 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 ₂ , or one or more particles selected from the group consisting of glass fibers, graphite, rock wool, and clay are preferable, but not always limited thereto, More than one species may be mixed and included in the spinning solution.

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

5A and 5B, the heat insulating portion 130 of the hybrid thermal insulation sheet according to the first and second embodiments of the present invention includes a laminated structure (FIG. 5A) of the nanofiber web 131 and the nonwoven fabric 132, Or a laminated structure of the nanofiber web 131 / nonwoven fabric 132 / nanofiber web 133 (FIG. 5B). At this time, it is preferable that the thickness t1 of the nanofiber web 131 is thinner than the thickness t2 of the nonwoven fabric 132.

When the heat insulating portion 130 is applied to the laminated structure of the nanofiber web 131 and the nonwoven fabric 132, the nonwoven fabric 132 is less expensive and has a higher strength than the nanofiber web 131, The manufacturing cost of the hybrid heat-insulating sheet can be reduced and the strength can be improved. In addition, since the nonwoven fabric 132 also has a plurality of pores, the nonwoven fabric 132 has a function of collecting heat, thereby performing the role of a heat insulating part.

The nano-fiber web 131 and the nonwoven fabric 132 may be fused due to thermal compression and the melting point of the nano-fiber web 131 may be designed to be lower than the melting point of the nonwoven fabric 132, It is preferable that the nanofiber web 131 is melted and fused to the nonwoven fabric 132. For example, when the polymer material for forming the nanofiber web 131 is applied as PVdF, since the melting point of the PVdF is 155 ° C, the nonwoven fabric 132 is a polyester-based material having a melting point higher than 155 ° C, A nonwoven fabric 132 made of one of nylon series and cellulosic series is applied.

Therefore, at the time of thermocompression bonding, the region of the nanofiber web 131 contacting the nonwoven fabric 132 is melted and fused to the nonwoven fabric 132. Since the pore size of the nonwoven fabric 132 is much larger than the pore size of the nano-web 132, a part of the molten nano-fiber web 131 penetrates into the pores of the nonwoven fabric 132. That is, after the thermocompression bonding is performed on the interface between the nonwoven fabric 132 and the nanofiber web 131 before thermocompression bonding, the nanofibrous web 131 (in the direction of the nanofiber web 131 and in the direction of the nonwoven fabric 132) ) Is spread and distributed. When the degree of melting of the nanofiber web 131 is adjusted, the nanofiber web 131 is melted into the pores of the nonwoven fabric 132, and the nano- The fibrous web 131 may be locked to improve adhesion between the nanofibrous web 131 and the nonwoven fabric 132.

In the present invention, a polymer substance in which PVdF and PAN are mixed in a ratio of 5: 5 can be applied as a polymer material forming a nano-web. At this time, the electrospun nanofibers are formed of a structure comprising a core made of PAN and an outer skin made of PVdF surrounding the core, and the nanofibers having such a structure are laminated to form a nanofiber web 131. When the nanofiber web 131 and the nonwoven fabric 132 having the core and the outer skin structure laminated are thermally compressed, the PVdF of the outer skin melts and fuses to the nonwoven fabric 132.

6 is a conceptual cross-sectional view for explaining heat flow in the hybrid thermal insulation sheet according to the first and second embodiments of the present invention.

The hybrid heat-insulating sheet according to the first and second embodiments of the present invention is attached to a heat-generating component and has a structure for dispersing heat generated from the heat-generating component, a structure for temporally delaying the dispersed heat, So that the heat insulating efficiency can be maximized.

6, when a hotspot 111 is intensively transferred to a local region of the heat spreader 110, the heat transmitted from the hot spot 111 is dispersed to the entire heat spreader 110 do.

When the heat transmitted from the hot spot 111 of the heat spreader 110 is filled in the heat spreader 110, the heat spreader 120 is transferred. Here, even if the heat spreader 110 is not filled with heat, heat is transmitted to the heat spread edge 120, which is close to the hot spot 111.

The heat spread zone 120 delays the time that the transmitted heat is transferred from the heat spread zone 120 to the heat insulating part 130. That is, since the heat spread zone 120 includes a phase change material (PCM), the heat transmitted to the heat spread zone 120 is absorbed by the phase change material. At this time, since the phase-change material continuously absorbs heat for a predetermined time until the phase-change material completely changes from a solid phase to a liquid phase, it is possible to delay the time from the heat-softening edge portion 120 to the heat-

The heat-delayed heat is transferred to the heat insulating portion 130. The heat insulating part 130 made of a nanofiber web captures heat transmitted from the heat insulating part 130 by three-dimensional micro pores to block heat.

As described above, the hybrid thermal insulation sheet according to an embodiment of the present invention disperses the heat transferred from the heat generating component in the heat spreader 110, and delays the heat in the heat spreading section 120 to the heat insulating portion 130 And the heat transferred from the heat insulating portion 130 is collected and blocked.

For example, when a 100 캜 heat is conducted to the hot spot 111 of the heat spreader 110, heat of 90 캜 is transmitted to the heat spread edge 120 by the dispersing function in the heat spread 110, 120 slows the time for transferring the heat to the heat insulating part 130 and is transferred to the heat insulating part 130 after being lowered to 70 캜 by latent heat by endothermic reaction of the phase change material. In the heat insulating part 130, the heat is collected in the nanofiber web to be lowered to 30 ° C to 40 ° C to be accumulated, thereby improving the heat insulating performance.

The hybrid thermal insulation sheet according to an embodiment of the present invention is formed so that the temperature of the heat transmitted from the heat spreader 110 to the heat paper edge 120 is 2 ° C -5 It is desirable to implement the thermo soft tip 120 as a phase change material which is phase-changed at a low temperature.

7 is a schematic cross-sectional view showing an electrospinning apparatus for forming a nanofiber web applied to a hybrid thermal insulation sheet according to first and second embodiments of the present invention.

Referring to FIG. 7, the electrospinning device includes a mixer 2 incorporating a stirrer 2 using a pneumatic mixing motor 2a as a driving source so as to prevent phase separation until a polymer material having a low thermal conductivity is mixed with a solvent, A mixing tank 1, and a plurality of spinning nozzles 4 to which a high voltage generator is connected. The polymer solution discharged from the mixing tank 1 to the plurality of spinning nozzles 4 connected to the metering pump not shown through the transfer tube 3 is passed through the spinning nozzle 4 charged by the high voltage generator, 5, and the nanofibers 5 are accumulated on the grounded collector 6 in the form of a conveyor moving at a constant speed to form the porous nanofiber web 7.

Generally, when a multi-hole radiation 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 away and are not collected. As a result, the separation membrane obtained using a multi-hole spinning pack becomes too bulky, making it difficult to form a separation membrane and causing radiation trouble.

In view of this, in the present invention, as shown in FIG. 7, by using an air electrospinning method in which air 4a is jetted for each spinning nozzle 4 by using a multi-hole spinning pack, The web 7 is produced.

That is, according to the present invention, air is injected from the outer circumference of the spinning nozzle when electrospinning is performed by air electrospinning, and thus the fiber composed of a polymer having a high volatility plays a dominant role in collecting and accumulating air, Can produce this high nanofiber web and minimize the radiation problems that may occur as the fibers fly.

In the present invention, when a polymer material having a low thermal conductivity is mixed with a heat-resistant polymer material, the mixture is preferably added to a two-component solvent to prepare a mixed spinning solution.

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

In the present invention, if necessary, the porous nanofiber web 7 obtained as described above is allowed to remain 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 carry out a calendering process after a process of controlling the amount of solvent and moisture.

The Pre-Air Dry Zone by the preheater 8 is a method in which air of 20 to 40 ° C is applied to the web by using a fan to remove the solvent remaining on the surface of the nanofiber web 7 By regulating the amount of water, the nanofiber web 7 can be controlled to be bulky, thereby increasing the strength of the separator and controlling the porosity.

In this case, when calendering is performed while the solvent is excessively volatilized, the porosity is increased but the strength of the nanofiber web is weakened. On the other hand, when the volatilization of the solvent is low, the nanofiber web is melted.

The method of forming the porous nanofiber web 10 using the electrospinning apparatus of FIG. 7 is such that a polymer material having a low thermal conductivity is first solved, a mixture of a polymer material having a low thermal conductivity and a heat resistant polymer material is dissolved in a solvent, Prepare. In this case, a predetermined amount of inorganic particles may be added to the spinning solution to reinforce the heat resistance, if necessary. In addition, when a nanofiber web is formed using a polymer material having a low thermal conductivity and an excellent heat resistance, for example, polyurethane (PU), the heat insulating property and the heat resistance property are simultaneously obtained.

Thereafter, the spinning solution is directly radiated to the collector 6 using an electrospinning device or is radiated to a porous substrate 11 such as a nonwoven fabric to form a single-layer porous nanofiber web 10 or a porous nanofiber web 10, And a porous substrate (11).

In the present invention, the porous nanofiber web 10 can be applied as a heat insulating material for a portable terminal, and can be applied as a heat insulating material for a building or a refrigerator. After manufacturing a nanofiber web sheet having a large area, It is also possible to use it.

In the case of a heat insulating material for a building or a refrigerator, if the obtained nanofiber web sheet is wide in width, it can be cut to a desired width and then folded in a plate shape to have a desired thickness or wound in a plate shape by a winding machine, After the core sheet is cut, a plurality of layers are laminated. In addition, after laminating in multiple layers, it can be cut into a desired shape. If necessary, a plurality of laminated nanofiber web sheets can be hot-pressed or cold-pressed to increase the lamination density.

On the other hand, in the present invention, when forming a nanofiber web, a spinning solution is spun onto a transfer sheet composed of a nonwoven fabric or a polyolefin-based film made of a polymer material that is not dissolved by a solvent contained in a spinning solution, After the web is formed, a nanofiber web sheet can be produced by laminating the nanofiber web with a nonwoven fabric while separating the nanofiber web from the transfer sheet, and the resulting sheet can be laminated in multiple layers. As the nanofiber web is produced using the transfer sheet described above, the productivity in the mass production process can be improved.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be construed as limited to the embodiments set forth herein. Various changes and modifications may be made by those skilled in the art.

100: Hybrid insulation sheet 110, 210: Heat spreader
120, 215: heat spread edge portions 130, 217:
131, 133: Nano fiber web 132: Nonwoven fabric
211a: adhesive sheet 211b, 219a: opening
219: release paper 260: hot plate

Claims (12)

A heat spreader for dispersing the transmitted heat;
An adhesive sheet adhered to the heat spreader and having a pattern shape having a plurality of openings;
A heat spread edge filled in the plurality of openings, the heat spreading device delaying the heat dispersed in the heat spreader in time and conducting the heat; And
And a heat insulating portion adhered to the adhesive sheet and collecting and insulating the heat transmitted in a time delayed by the heat paper edge portion. The hybrid thermal insulation sheet according to claim 1, wherein the heat-softening edge portion comprises a phase change material (PCM). 3. The hybrid thermal insulation sheet according to claim 2, wherein the phase change material is phase-changed at a temperature of 2 DEG C to 5 DEG C lower than the temperature of heat conducted from the heat spreader to the heat paper edge. The hybrid thermal insulation sheet according to claim 2, wherein the heat-softening edge portion is a film in which the powder of the phase change material is dispersed. The hybrid thermal insulation sheet according to claim 1, wherein the heat insulating portion is a nanofiber web integrated with a nanofiber and having a three-dimensional micropore structure. The hybrid heat-insulating sheet according to claim 5, further comprising inorganic particles on the nanofibers. The hybrid thermal insulation sheet according to claim 1, wherein the heat insulating portion is a laminated structure of a nanofiber web and a nonwoven fabric, or a structure in which a nanofiber web, a nonwoven fabric and a nanofiber web are sequentially laminated. The hybrid thermal insulation sheet according to claim 7, wherein the thickness of the nanofiber web is thinner than the thickness of the nonwoven fabric. The hybrid thermal insulation sheet according to claim 8, wherein the nonwoven fabric and the nanofiber web are thermally pressed to melt the nanofiber web region adjacent to the nonwoven fabric and fuse to the nonwoven fabric. 10. The method of claim 9,
Wherein the melting point of the nanofiber web is lower than the melting point of the nonwoven fabric. Bonding the adhesive sheet to the heat spreader;
Patterning the adhesive sheet to form a patterned adhesive sheet having a plurality of openings;
Filling a plurality of openings of the patterned adhesive sheet with a powder of phase change material;
Placing the heat spreader on a hot plate and making powder of the phase change material into a liquid phase change material at a temperature of the hot plate;
Releasing the heat spreader from the hot plate to phase-change the liquid phase-change material into a film phase-change material in a solid state; And
And adhering the heat insulating portion to the patterned adhesive sheet. 12. The method of claim 11,
The heat-
Fabrication of a hybrid insulation sheet, which is one of a laminated structure of a nanofiber web, a nanofiber web and a nonwoven fabric having a three-dimensional microporous structure integrated by a nanofiber, or a structure in which a nanofiber web, a nonwoven fabric and a nanofiber web are sequentially laminated Way.

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