Planar heat generating composite sheet

Abstract

The present invention relates to a sheet-like heating composite sheet, which includes: a sheet-like heating layer including a substrate having a certain width and length and made of synthetic resin, a plurality of electrodes coated on an upper surface of the substrate in a width direction of the substrate and arranged alternately in a length direction of the substrate at intervals with different polarities from each other, a conductive paste coated on the upper surface of the substrate between the plurality of electrodes and generating heat by resistance, and an insulating sheet attached to an upper portion of the conductive paste and made of synthetic resin; and a thermal insulation layer including a thermal insulation sheet attached to a lower portion of the sheet-like heating layer and made by impregnating aerogel into a non-woven fabric made of synthetic resin, and a protective sheet attached to a lower portion of the thermal insulation sheet and made of synthetic resin.

Description

Technical Field

[0001] This invention relates to a planar heating composite sheet, and more specifically, aims to provide a planar heating composite sheet with a structure that more reliably prevents heat loss to the lower part and transfers more heat to the upper part through uniform planar heating, and more reliably prevents damage caused by asphalt concrete or equipment loads applied during road snow melting paving construction and wheel loads applied after construction. Background Technology

[0002] Generally speaking, among traffic accidents that occur on roads, slip and fall accidents caused by icy roads in winter have a higher incidence rate, especially at steep slopes, overpasses, and tunnel entrances and exits, which are areas that are frequently icy.

[0003] Therefore, the number of casualties and huge property losses caused by traffic accidents of all sizes due to icy roads in winter is increasing year by year.

[0004] Furthermore, the initial snow removal work carried out due to heavy snow is very important, but when it is difficult to access the site due to ice, the snow removal work is relatively delayed, which greatly increases the risk of severe traffic congestion and traffic accidents.

[0005] On the other hand, although the effects of snow melting on light snow are resolved over time, in most cases no fundamental measures are taken to address snow and ice accumulation on roads during the transition period caused by snow melting due to heavy snow and when nighttime minimum temperatures drop sharply.

[0006] As the simplest method to prevent this, calcium chloride is widely used as a de-icing agent by spraying it on snowplows. However, the corrosion and damage to road infrastructure and the various negative environmental impacts are being identified as serious problems by environmental groups and road officials.

[0007] Therefore, in addition to the initial snow accumulation on steep slopes, overpasses, tunnel entrances and exits, etc., which are prone to snow accumulation and freezing in winter, there is a need for eco-friendly snow removal methods that can be applied more promptly and effectively to prevent life-threatening situations and huge economic losses caused by traffic disasters that confuse drivers on winter roads.

[0008] Based on the above requirements, a method has been proposed in the past to melt snow on the road surface by burying the heating medium in the form of a heating mesh arranged in a zigzag pattern on a mesh metal frame and using the heat emitted from the heating cables.

[0009] However, in the above method, most of the heat emitted from the heating cable is transferred to the lower part and dissipated into the ground. Therefore, it takes a long time for the heat to reach the road surface, and the amount of heat transferred is not large. As a result, it is impossible to carry out snow melting work on the road normally.

[0010] The reason for the above problem is that the thickness of the asphalt concrete pavement layer of the road is generally 20cm to 40cm, but the heating cable is buried at a depth of 5cm to 10cm from the surface of the asphalt concrete pavement layer. Therefore, the heat generated by the heating cable tends to move to the lower part, which has a higher heat capacity than the upper part.

[0011] Furthermore, as mentioned above, the problem with heating networks is that the heating cables are damaged and lose their function due to the asphalt concrete or equipment loads applied during construction and the wheel loads applied after construction, resulting in frequent reconstruction and increased maintenance costs.

[0012] Therefore, recently, such as Figure 1 As shown, the main method of linear heating is as follows: a groove 200 with a certain depth and length from the road surface is formed. Inside the groove 200, heat insulation material 300 for preventing heat loss to the lower part, a metal receiving part 400 with excellent thermal conductivity for accommodating the heating cable 500, the heating cable 500, and a fixing part 600 for fixing the upper end of the receiving part 400 are sequentially arranged. Then, a heat-conducting layer 700 filled with heat-conducting resin liquid is formed on the upper part of the receiving part 400.

[0013] As described above, the linear heating method prevents heat loss to the ground through the insulation material 300 arranged at the bottom, and most of the heat emitted from the heating cable 500 is quickly transferred to the road surface through the thermally conductive containment component 400 and the thermally conductive layer 700, thus greatly improving the snow melting efficiency of the road surface.

[0014] However, the above method has the following problems: it requires performing a number of tasks, including forming multiple grooves 200 with predetermined depth and length on the road, cleaning dust inside the grooves 200, placing heat insulation material 300 inside the grooves 200, placing a receiving component 400 on the upper part of the heat insulation material 300, placing a heating cable 500 inside the receiving component 400, placing a fixing component 600 for fixing the upper part of the receiving component 400, and filling the upper part of the receiving component 400 with a heat-conducting resin liquid for forming a heat-conducting layer 700. The setup work is not only cumbersome, but also takes a long time.

[0015] Furthermore, the problem of heat loss to the lower part through the sides of the housing component 400 and the heat-conducting layer 700 during the process of transferring heat from the heating cable to the road surface has not yet been resolved. Summary of the Invention

[0016] Technical issues

[0017] This invention was developed to solve the above-mentioned problems. The purpose of this invention is to provide a planar heating composite sheet with the following structure: it more reliably prevents heat loss to the lower part, and transfers more heat to the upper part through uniform planar heating, and more reliably prevents damage caused by asphalt concrete or equipment loads applied during road snow melting paving construction and wheel loads applied after construction.

[0018] Technical solution

[0019] According to one aspect of the present invention for achieving the above-mentioned objectives, a planar heating composite sheet is provided, comprising: a planar heating layer including a substrate having a certain width and length and made of synthetic resin; a plurality of electrodes coated on the upper surface of the substrate along the width direction and arranged alternately with different polarities along the length direction of the substrate; a conductive paste integrally coated on the upper surface of the substrate between the plurality of electrodes and heated by resistance; and an insulating sheet attached to the upper part of the conductive paste and made of synthetic resin; and a heat insulation layer including a heat insulation sheet attached to the lower part of the planar heating layer and formed by impregnating aerogel into a nonwoven fabric made of synthetic resin; and a protective sheet attached to the lower part of the nonwoven fabric sheet and made of synthetic resin.

[0020] The thickness of the aforementioned heat insulation layer is 1mm to 5mm.

[0021] Furthermore, the aforementioned conductive paste comprises 20 to 40 parts by weight of amorphous co-polyester resin, 2.5 to 7.5 parts by weight of carbon nanotubes, 2.5 to 7.5 parts by weight of carbon nanoplates, and the remainder of graphene, silver (Ag) powder, carbon dispersant, and solvent.

[0022] On the other hand, the aforementioned carbon dispersant is a combination of at least two of carboxymethyl cellulose, polystyrene sulfonate, chondroitin sulfate, and hyaluronic acid.

[0023] Furthermore, the aforementioned planar heating composite sheet also includes a protective layer, which is attached to the upper part of the planar heating layer and the lower part of the heat insulation layer and is formed by impregnating asphalt and rubber into a non-woven fabric made of synthetic resin.

[0024] Furthermore, during the construction of road snow melting paving, the electrodes of the same polarity in adjacent planar heating layers are directly connected by conductive wires.

[0025] Technical effect

[0026] According to the present invention as described above, by more reliably preventing heat loss to the lower part and by transferring more heat to the upper part through uniform planar heating, the upward heat transfer efficiency is greatly improved. Therefore, when applied to road snow melting paving, the snow melting efficiency can be significantly improved, and the corresponding power consumption can be greatly reduced.

[0027] Furthermore, by more reliably preventing damage caused by asphalt concrete or equipment loads applied during road snow melting and paving construction, as well as wheel loads applied after construction, maintenance costs due to reconstruction can be reduced. Attached Figure Description

[0028] Figure 1 The diagram illustrates the current state of road snow melting and paving construction.

[0029] Figure 2 This is a perspective view of a planar heating composite sheet according to an embodiment of the present invention.

[0030] Figure 3 This is an exploded perspective view of a planar heating composite sheet according to an embodiment of the present invention.

[0031] Figure 4 for Figure 2 A-A' section view.

[0032] Figure 5 A graph showing the heating rate of snow melting paving using existing linear heating methods and snow melting paving with a planar heating composite sheet embedded according to an embodiment of the present invention.

[0033] Figure 6a and Figure 6b This diagram illustrates the connection structure between electrodes of a planar heating composite sheet according to an embodiment of the present invention.

[0034] Figure 7 The diagram illustrates the connection structure between electrodes of a planar heating composite sheet according to an embodiment of the present invention.

[0035] Optimal implementation form of the invention

[0036] The invention will be described in more detail below with reference to the accompanying drawings. It should be noted that the same reference numerals are used as much as possible in the drawings to denote common elements. Furthermore, specific descriptions of known functions and structures that would unnecessarily obscure the gist of the invention will be omitted.

[0037] Figure 2 This is a perspective view of a planar heating composite sheet according to an embodiment of the present invention. Figure 3 This is an exploded perspective view of a planar heating composite sheet according to an embodiment of the present invention. Figure 4 for Figure 2 A-A' section view.

[0038] Reference Figures 2 to 4 According to an embodiment of the present invention, the planar heating composite sheet 1 includes a planar heating layer 10, a heat insulation layer 20 and a protective layer 30.

[0039] The planar heating layer 10 generates heat through resistance when powered, and includes a substrate 11, an electrode 12, a conductive paste 13, and an insulating sheet 14.

[0040] The substrate 11 is made of synthetic resin and provides the area where the electrode 12 and conductive paste 13 are coated. At the same time, it performs the function of insulation to prevent the current applied to the electrode or conductive paste from leaking to the lower part.

[0041] Electrode 12 provides the input and output path for the supplied current, is coated along the width direction of substrate 11, and different polarities are arranged alternately at predetermined intervals along the length direction of substrate 11.

[0042] The electrode 12 is formed by coating a paste containing silver powder onto the upper surface of the substrate 11 and then curing it.

[0043] The conductive paste 13 generates heat through resistance when an electric current is applied, and is generally coated between multiple electrodes 12 on the upper surface of the substrate 11.

[0044] The conductive paste 13 comprises 20 to 40 parts by weight of amorphous copolyester resin, 2.5 to 7.5 parts by weight of carbon nanotubes, 2.5 to 7.5 parts by weight of carbon nanoplates, and the remainder of graphene, silver powder, carbon dispersant, and solvent.

[0045] The amorphous copolyester resin, used as a binder, enables the conductive paste 13 to have uniform dispersibility and excellent coatability while maintaining adhesion to the substrate 11.

[0046] In particular, the amorphous copolyester resin imparts tensile stress to the conductive paste 13. When the content of the amorphous copolyester resin is less than 20 parts by weight, it cannot impart sufficient tensile stress to the conductive paste 13. When the content of the amorphous copolyester resin is greater than 40 parts by weight, the conductive paste 13 cannot perform its conductive function normally. Therefore, it is preferable to use 20 to 40 parts by weight of amorphous copolyester resin.

[0047] Carbon nanotubes and carbon nanoplates are conductive materials. When their content is less than 2.5 parts by weight, they cannot perform their conductive function properly. When their content is greater than 7.5 parts by weight, they may hinder the tensile stress imparted to the conductive paste 13 by the amorphous copolyester resin. Therefore, their content is preferably 2.5 parts by weight to 7.5 parts by weight.

[0048] The carbon dispersant is used to uniformly disperse carbon nanotubes and carbon nanoplates in the conductive paste 13, and at least two of carboxymethyl cellulose, polystyrene sulfonic acid, chondroitin sulfate and hyaluronic acid are used as carbon dispersants in combination.

[0049] The solvent used to dissolve the amorphous copolyester resin may include alpha-terpineol, butyl cellosolve, ethyl cellosolve, ethyl carbitol, butyl carbitol, ethoxyethyl acetate, butyl acetate, propylene glycol monomethyl ether, γ-butyrolactone, methyl ethyl ketone, or combinations thereof.

[0050] Since the conductive paste 13 of the present invention has the composition ratio described above, it imparts tensile stress to the conductive film formed by the conductive paste 13, which can resist the shear force caused by the asphalt concrete or equipment load applied during the construction of the road snow melting paving and the wheel load applied after construction. Therefore, the damage to the conductive film caused by shear force can be minimized.

[0051] The insulating sheet 14 is made of synthetic resin and is attached to the upper part of the electrode 12 and the conductive paste 13, and performs the function of insulation to prevent the current applied to the electrode or conductive paste from leaking to the upper part.

[0052] The heat insulation layer 20 is used to prevent heat emitted from the planar heating layer 10 from being lost to the ground, and includes a heat insulation sheet 21 attached to the lower part of the planar heating layer 10 and a protective sheet 22 attached to the lower part of the heat insulation sheet 21.

[0053] The planar heating composite sheet 1 of the present invention is constructed at a relatively shallow depth of about 7cm to 8cm from the road surface. Therefore, the material, structure, and thickness of the insulation layer 20 are very important. In other words, generally used thick insulation materials are easily damaged or destroyed by the load of asphalt concrete or equipment during construction. Therefore, it is necessary to meet the very difficult condition of being both very thin and having high insulation efficiency.

[0054] The heat insulation sheet 21 of the present invention, which is used to simultaneously meet the requirements of thickness and heat insulation efficiency, has a structure in which aerogel is impregnated in a non-woven sheet made of synthetic resin, and the heat insulation layer 20 including the protective sheet 22 has a thickness of 1 mm to 5 mm.

[0055] Among them, the aerogel has a structure containing more than 90% fine air inside, so it has excellent heat insulation performance by blocking heat through convection, conduction and radiation, thus more reliably preventing heat from the surface heating layer 10 from being lost to the ground.

[0056] Furthermore, a nonwoven sheet made of synthetic resin is used as a framework for distributing the aerogel in sheet form. Preferably, it is made to have a tensile stress of 2 MPa to 20 MPa to resist the shear stress caused by asphalt concrete or equipment loads applied during the construction of the road snow melting paving and the wheel loads applied after construction, thereby preventing the aerogel from being damaged by shear stress.

[0057] When the thickness of the insulation layer 20 is less than 1 mm, the insulation effect is minimal. When the thickness of the insulation layer 20 is greater than 5 mm, the risk of damage caused by asphalt concrete or equipment load during construction increases.

[0058] The protective sheet 22 is made of synthetic resin and is attached to the lower part of the heat insulation sheet 21. It serves to prevent the fine air contained inside the aerogel from escaping to the outside. At the same time, it serves to prevent asphalt from flowing into the heat insulation sheet 21 and penetrating into the micropores of the aerogel during construction.

[0059] The protective layer 30 is used to prevent damage to the planar heating layer 10 and the heat insulation layer 20 caused by shear stress from asphalt concrete or equipment loads applied during the road snow melting paving construction and wheel loads applied after construction. The protective layer 30 is attached to the upper part of the planar heating layer 10 and the lower part of the heat insulation layer 20, respectively.

[0060] The aforementioned protective layer 30 has a structure in which asphalt and rubber are impregnated into a nonwoven fabric made of synthetic resin.

[0061] The reason for using nonwoven fabric made of synthetic resin is, as mentioned above, to resist the shear stress caused by asphalt concrete or equipment loads applied during construction and wheel loads applied after construction through tensile stress.

[0062] Furthermore, the reason for impregnating the asphalt and rubber is to ensure sufficient adhesion between them and the asphalt concrete during construction.

[0063] As described above, the planar heating composite sheet 1 according to an embodiment of the present invention, by impregnating the aerogel into a non-woven sheet made of synthetic material, more reliably prevents heat emitted from the planar heating layer from dissipating to the lower part, thereby significantly improving snow melting efficiency and correspondingly reducing power consumption when applied to road snow melting paving.

[0064] Furthermore, the insulation sheet of the insulation layer and the base layer of the protective layer are formed from non-woven fabric sheets made of synthetic resin. Therefore, the tensile stress of the non-woven fabric sheets can resist the shear force generated by the asphalt concrete or equipment load applied during the construction of the road snow melting paving and the wheel load applied after construction, thereby more reliably preventing damage.

[0065] Therefore, the reduced likelihood of reconstruction not only decreases the costs associated with reconstruction but also significantly improves durability.

[0066] Figure 5 A graph showing the heating rate of snow melting paving using existing linear heating methods and snow melting paving with a planar heating composite sheet embedded according to an embodiment of the present invention.

[0067] Reference Figure 5 Under the existing linear heating method for snow melting paving, the heat output per unit area is 300W / m². 2 At that time, the time required for the surface temperature to rise from -5℃ to 2℃ was 358 minutes, and the heat generation per unit area was 600W / m². 2 At that time, the time required for the surface temperature to rise from -5℃ to 2℃ was 125 minutes, and the heat generation per unit area was 900W / m². 2 At that time, the time required for the surface temperature to rise from -5℃ to 2℃ was 82 minutes, and the heat generation per unit area was 1200W / m². 2 At that time, the time required for the surface temperature to rise from -5℃ to 2℃ was 63 minutes.

[0068] On the other hand, in the case of snow-melting paving with a planar heating composite sheet according to an embodiment of the present invention, the heat generation per unit area is 300W / m. 2 At that time, the time required for the surface temperature to rise from -5℃ to 2℃ was 141 minutes, and the heat generation per unit area was 600W / m². 2 At that time, the time required for the surface temperature to rise from -5℃ to 2℃ was 67 minutes, and the heat generation per unit area was 900W / m². 2 At that time, the time required for the surface temperature to rise from -5℃ to 2℃ was 48 minutes, and the heat generation per unit area was 1200W / m². 2 When the surface temperature reaches 2°C from -5°C, it takes 39 minutes. Therefore, the planar heating composite sheet according to the present invention has excellent snow melting efficiency and significantly reduces power consumption.

[0069] Figure 6a and Figure 6bThis diagram illustrates the connection structure between electrodes of a planar heating composite sheet according to an embodiment of the present invention.

[0070] During road snow melting and paving construction, such as Figure 6a and Figure 6b As shown, the above-mentioned planar heating composite sheet 1 is arranged side by side along the width direction of the road.

[0071] Furthermore, the electrodes 12 of different polarities arranged along the length direction of each planar heating composite sheet 1 are connected to the power supply unit through conductive lines.

[0072] In the past, such as Figure 6a As shown, each electrode 12 of each planar heating composite sheet 1 is connected to the power supply unit via conductive wire 40.

[0073] However, in the above method, each electrode 12 needs to be connected to the power supply unit one by one through the conductive wire 40. Therefore, not only is the setup work cumbersome, but also the arrangement of the conductive wire 40 takes a lot of time due to the large number of conductive wires 40.

[0074] Furthermore, each conductive wire 40 is positioned across the area where the planar heating composite sheet 1 is arranged, which is the area in contact with the wheel. Therefore, the conductive wire 40 may break due to the load of the wheel.

[0075] For the reasons mentioned above, such as Figure 6b As shown, in this invention, the electrodes 12 of the same polarity of each adjacent planar heating composite sheet 1 are directly connected by conductive wire 40, and any one of the interconnected electrodes of the same polarity is connected to the power supply unit.

[0076] With the above structure, compared with the prior art, the length of the conductive line 40 is significantly reduced, the setup work is made easier by connecting adjacent electrodes, and no separate alignment work is required because the conductive lines 40 do not overlap each other.

[0077] Furthermore, the conductive wire 40 does not have an area where wheel loads are applied, so there is no problem of the conductive wire 40 breaking due to wheel loads.

[0078] Figure 7 The diagram illustrates the connection structure between electrodes of a planar heating composite sheet according to an embodiment of the present invention.

[0079] The electrode connection structure of the planar heating composite sheet according to an embodiment of the present invention is as follows: Figure 7 As shown, through holes H are formed at the edges of each electrode 12 of adjacent planar heating composite sheets 1, penetrating the insulating sheet and protective layer arranged on the upper part, and the two ends of the strip conductive wire 40 are welded to each electrode exposed through the through holes H.

[0080] While the preferred embodiments of the present invention have been described above, various modifications and variations can be made without departing from the spirit and scope of the invention. Therefore, the appended claims are intended to cover such modifications and variations falling within the spirit of the invention.

Claims

1. A planar heating composite sheet, characterized in that, The aforementioned planar heating composite sheet is embedded at a depth adjacent to the road surface and is used for road snow melting, and includes: A planar heating layer includes a substrate of a certain width and length made of synthetic resin; a plurality of electrodes coated on the upper surface of the substrate along the width direction and arranged alternately with different polarities along the length direction of the substrate; a conductive paste coated on the upper surface of the substrate between the plurality of electrodes and heated by resistance; and an insulating sheet made of synthetic resin attached to the conductive paste; and The thermal insulation layer includes a thermal insulation sheet made by impregnating aerogel into a nonwoven fabric made of synthetic resin having a tensile stress of 2 MPa to 20 MPa, and a protective sheet made of synthetic resin attached to the lower part of the thermal insulation sheet. The aforementioned heat insulation layer includes areas corresponding to the regions where the electrodes are disposed and the regions where the conductive paste is disposed, and is attached to the entire lower surface of the substrate of the aforementioned planar heating layer. Among these electrodes, adjacent electrodes of the same polarity are directly connected by conductive wires, and any one of the interconnected electrodes of the same polarity is directly connected to the power supply unit. The aforementioned adjacent electrodes of the same polarity are exposed through through holes in the insulating sheet disposed on the upper part of the electrodes. The aforementioned conductive wire has an electrode connection structure that connects the exposed portions of the aforementioned electrodes. The aforementioned connection structure between electrodes prevents the conductive wires from breaking due to wheel loads and improves the alignment of the conductive wires. The thickness of the aforementioned insulation layer is configured to be 1 mm to 5 mm. The aforementioned protective sheet of the heat insulation layer prevents asphalt from the road from flowing into the heat insulation sheet and penetrating into the micropores of the aerogel. The conductive paste comprises 20 to 40 parts by weight of amorphous copolyester resin, 2.5 to 7.5 parts by weight of carbon nanotubes, 2.5 to 7.5 parts by weight of carbon nanoplates, and the remainder of graphene, silver powder, carbon dispersant, and solvent.

2. The planar heating composite sheet according to claim 1, characterized in that, The aforementioned carbon dispersant is a combination of at least two of carboxymethyl cellulose, polystyrene sulfonic acid, chondroitin sulfate, and hyaluronic acid.

3. The planar heating composite sheet according to claim 1, characterized in that, It also includes a protective layer, which is attached to the upper part of the planar heating layer and the lower part of the heat insulation layer and is formed by impregnating asphalt and rubber into a non-woven fabric made of synthetic resin.

4. The planar heating composite sheet according to claim 1, characterized in that, During the construction of road snow melting paving, the electrodes of the same polarity of adjacent planar heating layers are directly connected through the aforementioned conductive wires.

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