CN209748840U

CN209748840U - Electric heating film and electric heating product

Info

Publication number: CN209748840U
Application number: CN201821787253.8U
Authority: CN
Inventors: 吴祯琪; 刘兆平
Original assignee: Ningbo Graphene Innovation Center Co Ltd
Current assignee: Ningbo Graphene Innovation Center Co Ltd
Priority date: 2018-10-31
Filing date: 2018-10-31
Publication date: 2019-12-06
Anticipated expiration: 2028-10-31

Abstract

The utility model provides an electric heat membrane and electric heat product belongs to the electricity technical field that generates heat. The electrothermal film comprises a first protective layer, a second protective layer and a heating layer, the heating layer comprises a heating area and a converging area which are made of the same materials, the surface of the heating area forms the converging area, the thickness of the converging area is 1.01-10 times of that of the heating area, and the heating area and the converging area are both clamped between the first protective layer and the second protective layer. The thickness in the district that converges on this electric heat membrane's the layer that generates heat is greater than the thickness in the district that generates heat, avoids the electric heat membrane to generate heat between layer and the busbar resistance too high, and it is too big to generate heat, improves the stability of electric heat membrane, prolongs the life of electric heat membrane, and need not set up silver thick liquid coating, reduction in manufacturing cost.

Description

Electric heating film and electric heating product

Technical Field

the utility model relates to an electricity technical field that generates heat particularly, relates to an electric heat membrane and electric heat product.

Background

People have continuous pursuit for life with higher quality, and along with the increasing improvement of living standard of people, not only the product is required to meet basic functions, but also the product is required to be more efficient, more environment-friendly, more stable and safer. Compared with traditional low-efficiency, polluted and unsafe combustion heating, the electric heating has the characteristics of high efficiency, environmental protection, safety and the like, and is gradually popularized in recent years. The electric heating warming products are various, and the popularization speed of the electric heating film is faster and faster.

The conventional electric heating film is mainly divided into three layers: an upper protective layer, a heating layer and a lower protective layer/substrate. Wherein, the heating layer is mainly prepared by curing after printing or coating conductive ink. The both ends on the layer that generates heat are equipped with the busbar, and the effect of busbar is the connection power, provides voltage, generally is two copper foil strips. The district that converges between the layer and the copper foil strip that generate heat of traditional product has resistance too high, the too big problem of generating heat, influences stability and the life-span of electric heat membrane product itself. Therefore, a silver paste coating is usually used as a transition between the heat generating layer and the copper foil strip to reduce the resistance between the heat generating layer and the copper foil strip. However, the silver paste coating contains noble metals, so that the price is high, and the silver paste coating needs to be printed separately, so that the cost of the electrothermal film is high.

SUMMERY OF THE UTILITY MODEL

A first object of the utility model is to provide an electric heat membrane, the district resistance that converges of the layer of avoiding generating heat of electric heat membrane is too high, generates heat too big, improves the stability of electric heat membrane, prolongs the life of electric heat membrane, and need not set up silver thick liquid coating, reduces manufacturing cost.

A second object of the present invention is to provide an electric heating product, which uses the above electric heating film to make the heating of the electric heating product more stable and prolong the service life of the electric heating product.

Based on above-mentioned first purpose, the utility model discloses an adopt following technical scheme to realize:

The utility model provides an electrothermal film, includes first protective layer, second protective layer and generates heat the layer, generates heat the layer including the same district that generates heat of material with converge the district, the surface formation in the district that generates heat converges, the thickness in the district that converges is 1.01-10 times of the thickness in district that generates heat, generate heat the district with converge the district and all press from both sides between first protective layer and second protective layer.

Further, in another embodiment of the present invention, the heat generating region continuously transits to the converging region.

Further, in another embodiment of the present invention, the continuous transition is selected from at least one of a linear increase in thickness along the planar direction and a curvilinear increase in thickness along the planar direction.

Further, in another embodiment of the present invention, the continuous transition is a thickness gradient of the transition region not higher than 100 microns/1000 microns.

Further, in another embodiment of the present invention, the electric heating film further includes a bus bar, the bus bar area is provided with a bus groove, and the bus bar is embedded in the bus groove.

Further, in another embodiment of the present invention, the electric heating film heating layer further includes a blank area, and the blank area is located in the heating area.

Further, in another embodiment of the present invention, the blank area is continuously transited to the heating area, and the blank area is continuously transited to the converging area.

further, the utility model discloses an in another embodiment, above-mentioned district that generates heat includes the heating strip that many intervals set up, and the both ends of every heating strip are equallyd divide and are do not set up a district that converges, form blank area between two adjacent heating strips. Further, in another embodiment of the present invention, the heat generating area has a plurality of through holes, and each of the through holes is a blank area.

An electric heating product comprises the electric heating film.

Compared with the prior art, the utility model provides an electric heat membrane's beneficial effect includes: the district that converges is formed on the surface in the district that generates heat, and the thickness in the district that converges all is greater than the thickness in the district that generates heat, and the sectional area increase in the district that converges, so, the total resistance in the district that converges reduces, then the heating power in the district that converges reduces, avoids the district department that converges to generate heat too big, improves the stability of electric heat membrane, prolongs the life of electric heat membrane. Because the material that converges the district and generate heat the district the same, avoid setting up silver thick liquid coating at the both ends on electric heat membrane layer that generates heat, reduce manufacturing cost.

The utility model provides an electric heating product's beneficial effect includes: the electric heating product uses the electric heating film, the heating of the obtained electric heating product is more stable, and the service life of the electric heating product is prolonged.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention, and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained from the drawings without creative efforts, and the protection scope of the present invention also belongs to the protection scope of the present invention.

Fig. 1 is a schematic cross-sectional view of an electrothermal film provided in embodiment 1 of the present invention;

Fig. 2 is a schematic plan view of a first plane of a heating layer in an electric heating film provided in embodiment 1 of the present invention;

Fig. 3 is a second schematic plan view of a heating layer in an electric heating film provided in embodiment 1 of the present invention;

Fig. 4 is a third schematic plane view of a heating layer in an electric heating film provided in embodiment 1 of the present invention;

Fig. 5 is a schematic view of a first cross section of a heating layer in an electrothermal film according to embodiment 1 of the present invention;

Fig. 6 is a schematic second cross-sectional view of a heating layer in an electric heating film provided in embodiment 1 of the present invention.

icon: 10-a heat-generating layer; 20-a first protective layer; 30-a second protective layer; 110-a heat-generating zone; 120-confluence area; 130-a bus bar; 140-blank area.

Detailed Description

in order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention, as generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the accompanying drawings, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

it should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

Example 1

Referring to fig. 1, the electrothermal film includes a first protective layer 20, a second protective layer 30, a heat generating layer 10 and two bus bars 130. The power supply is connected through the two bus bars 130, so that the electric heating film is electrified to heat.

The bus bar 130 may be a combination of one or more of a ribbon made of a metal foil and a bar coating obtained by drying a metal paste. Optionally, the bus bar 130 is one or a combination of copper foil tape, aluminum foil tape, and stainless steel tape.

The heat generating layer 10 is sandwiched between the first protective layer 20 and the second protective layer 30 for protecting the heat generating layer 10. The first protection layer 20 is identical to the second protection layer 30, and the structure of the first protection layer 20 and the structure of the second protection layer 30 are not improved in this embodiment, and are not described in detail herein.

Referring to fig. 1 to 6, the heat generating layer 10 includes a blank region 140, a heat generating region 110 and two bus regions 120. In this embodiment, the number of the convergence regions 120 is not limited to two, and may be adjusted according to product requirements. The middle region of the heat-generating layer 10 is a heat-generating region 110, which is mainly responsible for converting electric energy into heat energy after being electrified. The first protective layer 30 and the second protective layer 30 are disposed at both sides of the heat generating region 110 and each bus bar region 120, respectively.

Alternatively, the heat generating region 110 may be a continuous planar structure (as shown in fig. 2), a stripe structure (as shown in fig. 3), or a combination of one or more hollow structures (as shown in fig. 4) from a top view. In the case of the stripe structure and the hollow structure, there is a region without the heat-generating coating, i.e., the blank region 140, and the blank region 140 is located in the heat-generating region 110.

For example: referring to fig. 3, the heating region 110 includes a plurality of heating bars arranged at intervals, a convergence region 120 is respectively arranged at both ends of each heating bar, and a blank region 140 is formed between two adjacent heating bars, so that the heating region 110 forms a stripe structure.

Referring to fig. 4, the heating region 110 has a plurality of through holes therein, each of which is a blank region 140, so that the heating region 110 forms a hollow structure. The shape of the through holes may be square, circular or other irregular shapes.

Referring to fig. 1, 5 and 6, two ends of the heat generating region 110 are respectively provided with a bus bar region 120, one side of each bus bar region 120 away from the heat generating region 110 is provided with a bus bar groove, and one bus bar 130 is embedded in one bus bar groove.

The two bus bars 130 are connected to an external power source, and transmit voltage to both ends of the heating region 110 through the two bus bars 120, so that both ends of the heating region 110 are connected to the external power source, and the heating region 110 generates heat.

The thickness of each convergence region 120 is 1.01 to 10 times the thickness of the heat generation region 110. The sectional area increase of district 120 converges, so, the resistance of the district 120 that converges reduces, then the power that generates heat of the district 120 that converges reduces, avoids the district 120 department that converges to generate heat too big, improves the stability of electric heat membrane, prolongs the life of electric heat membrane.

Optionally, the thickness of each converging region 120 is 1.01-6 times that of the heating region 110, so that the cost is reduced, and the use efficiency of materials is increased. Further, the thickness of each confluence region 120 is 2-6 times that of the heat generating region 110. Further, the thickness of each convergence region 120 is 2 to 4 times the thickness of the heat generating region 110.

The heat generating region 110 continuously transitions to each bus region 120. The blank region 140 is continuously transited to the heat generating region 110, and the blank region 140 is continuously transited to each bus region 120.

that is, the heat generating region 110 is gradually thickened toward each of the merging regions 120, the blank region 140 is gradually thickened toward each of the merging regions 120, and the blank region 140 is gradually thickened toward the heat generating region 110.

Thus realizing continuous transition and forming a transition area with slow transition of thickness gradient. If the thickness between two adjacent areas changes violently, can lead to its generate heat and the violent change of temperature, has an influence to the stability of electric heat membrane, can influence holistic life and security.

Thus, a continuous transition means that the thickness gradient in the transition region is not higher than 100/1000 microns. Optionally, the thickness gradient of the transition region is no higher than 50/1000 microns. Further, the thickness gradient of the transition region is not higher than 10/1000 μm.

It is noted that the continuous transition is selected from at least one of a linear increase in thickness with the in-plane direction (e.g., fig. 1) and a curvilinear increase in thickness with the in-plane direction (e.g., fig. 6). The surface of the transition region away from the heat generating region 110 may be an inclined plane, an inclined arc surface, or both an inclined plane and an inclined arc surface.

The heating area 110 and each current converging area 120 are made of the same material, so that the current transmission stability of the current converging areas 120 and low heating in working are guaranteed, and no metal transition layer is required to be additionally arranged. Therefore, the current-collecting region 120 does not contain a metal transition layer, that is, the current-collecting region 120 does not contain one or more of a silver paste coating and a copper paste coating, thereby reducing the manufacturing cost.

The materials of the heat generating region 110 and the bus bar region 120 include a conductive filler and a resin binder. The conductive filler is all conductive materials and conductive additives available on the market. Optionally, the conductive filler is selected from at least one of graphite, carbon black, carbon nanotubes, carbon fibers, carbon crystals, graphene, fullerene, copper powder, silver powder.

The resin binder is all commercially available resin binder products. The resin is at least one selected from epoxy resin, phenolic resin, acrylic resin, alkyd resin, polyurethane resin, polyester resin, organic silicon resin, fluorocarbon resin, vinyl resin, cellulose resin and polyamide resin. The resin binder product may be a combination of one or more of a melt, solution, emulsion and dispersion of the resin.

An electric heating product comprises the electric heating film without gaps inside, and the electric heating product can be prepared by using the electric heating film without gaps inside. For example: heating foot pad, electric blanket, heating mouse pad, heat preservation membrane etc.. The heating of the electric heating product is more stable, and the service life is longer.

A preparation method of the heating layer 10 in the electric heating film is characterized in that conductive ink is used for forming a film on the surface of a base material to prepare the heating layer 10. The conductive ink is a material for preparing the heat generating region 110 and the bus region 120. The conductive ink may also include one or both of a solvent and an ink adjuvant.

The substrate is one or the combination of a plurality of films, plates and fabrics. The first protective layer 20 or the second protective layer 30 may be a base material in a film forming step, or may be a combination of one or more of a single protective film and a protective coating.

The film formation means that the heat generating region 110 is formed on the surface of the substrate, and two bus regions 120 are formed at both ends of the surface of the heat generating region 110 away from the substrate. Film formation can be achieved by one or a combination of printing, coating, spraying, and printing.

Alternatively, the heat generating layer 10 is formed on the surface of the substrate by using a conductive ink. For preparing the heat generating layers 10 having different thicknesses, it is common to apply multiple coatings or a manner similar to a multilayer stack to achieve the purpose of having the heat generating layers 10 having different thicknesses. However, the thickness of the heat generating layer 10 obtained by these methods varies greatly between different regions. And the layers obtained by overlapping the layers for many times have interface effect, which is one of unstable and unsafe factors.

Therefore, the heat generating layer 10 with different thicknesses is continuously transited to form a transition region, the bus region 120 is gradually thickened, the thickness of the two adjacent regions is prevented from being changed violently, and the stability of the heating film is further improved.

Example 2

The carbon crystal conductive ink is used as a raw material, cylindrical coating rollers with meshes of different meshes are adopted to coat on an epoxy resin substrate, and the heating layer 10 is formed after drying. And covering two confluence areas 120 at two ends of the surface of the heating layer 10 far away from the substrate with copper foil bus bars 130 respectively, and covering one side of the heating layer 10 far away from the substrate with a protective layer to finish the manufacture of the electrothermal film product.

Wherein, the mesh of the coating roller in the heating area 110 is 250 meshes of shallow holes, the mesh of the confluence area 120 is 100 meshes of deep holes, and the boundary area is gradually transited by a gradient of 30 meshes/100 micrometers. A section of 1 cm wide part of the coating roll manifold 120 was used with 150 mesh mesopores.

The produced heat generating layer 10 is of a continuous planar configuration. Referring to FIG. 6, it is tested that the thickness of the heat generating region 110 is 5 microns, the thickness of the bus region 120 is 50 microns, and the thickness gradient of the transition region is 90 microns/1000 microns. The groove width of the converging region 120 is 1 cm, and the depth is 10 microns. After the power is on, the heating area 110 heats stably, and the converging area 120 does not heat.

Example 3

The graphene conductive ink is used as a raw material, gravure printing rollers with meshes of different meshes are adopted to coat the PET film, and the heating layer 10 is formed after drying. Two converging areas 120 at two ends of the surface of the heating layer 10 far away from the PET film are respectively coated with copper foil bus bars 130, then one side of the heating layer 10 far away from the PET film is coated with a PET protective film, and the electric heating film product is manufactured after hot-pressing compounding.

Wherein, the mesh of the coating roller in the heating area 110 is 200 meshes of shallow holes, the mesh of the confluence area 120 is 100 meshes of deep holes, and the boundary area is gradually transited by a gradient of 20 meshes/100 micrometers. A section of 1 cm wide part of the gravure roll manifold 120 used 150 mesh mesopores.

the produced heat generating layer 10 has a stripe structure. Referring to FIG. 6, it is tested that the thickness of the heat generating region 110 is 10 microns, the thickness of the bus region 120 is 35 microns, and the thickness gradient of the transition region is 50 microns/1000 microns. The groove width of the converging region 120 is 1 cm, and the depth is 15 microns. After the power is on, the heating area 110 heats stably, and the converging area 120 does not heat.

Example 4

The graphene/copper powder mixed conductive ink is used as a raw material, gravure printing rollers with meshes of different meshes are adopted to coat the PET film, and the heating layer 10 is formed after drying. Two converging areas 120 at two ends of the surface of the heating layer 10 far away from the PET film are respectively coated with copper foil bus bars 130, then one side of the heating layer 10 far away from the PET film is coated with a PET protective film, and the electric heating film product is manufactured after hot-pressing compounding.

Wherein, the mesh of the coating roller in the heating area 110 is 140 meshes of shallow holes, the mesh of the confluence area 120 is 100 meshes of deep holes, and the boundary area is gradually transited by a gradient of 10 meshes/100 micrometers.

The produced heat generating layer 10 has a stripe structure. Referring to FIG. 6, it is tested that the thickness of the heat generating region 110 is 10 microns, the thickness of the bus region 120 is 15 microns, and the thickness gradient of the transition region is 12.5 microns/1000 microns. After the power is on, the heating area 110 heats stably, and the converging area 120 does not heat.

Example 5

The method comprises the steps of using graphene conductive ink as a raw material, coating the graphene conductive ink on a PET film by using a gravure printing roller with 200-mesh shallow holes, drying the PET film, and printing two ends of a heating layer 10 by using a gravure printing roller with only a confluence area 120 with 200-mesh shallow holes to form the heating layer 10. Two converging areas 120 at two ends of the surface of the heating layer 10 far away from the PET film are respectively coated with copper foil bus bars 130, then one side of the heating layer 10 far away from the PET film is coated with a PET protective film, and the electric heating film product is manufactured after hot-pressing compounding.

The produced heat generating layer 10 has a stripe structure. Referring to fig. 5, it is tested that the thickness of the heat generating region 110 is 10 micrometers, the thickness of the bus region 120 is 30 micrometers, and there is no transition region. After the power is on, the heating area 110 generates heat stably, the converging area 120 generates a small amount of heat, and a small amount of air holes are found at the junction of the heating area 110 and the converging area 120.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An electrothermal film is characterized by comprising a first protective layer, a second protective layer and a heating layer, wherein the heating layer comprises a heating area and a converging area which are made of the same material, the converging area is formed on the surface of the heating area, the thickness of the converging area is 1.01-10 times that of the heating area, and the heating area and the converging area are clamped between the first protective layer and the second protective layer;

The electric heating film further comprises a bus bar, wherein a bus groove is formed in the bus area, and the bus bar is embedded in the bus groove.

2. The electrothermal film according to claim 1, wherein the heat generating region continuously transitions to the current converging region.

3. The electrothermal film of claim 2, wherein the continuous transition is selected from at least one of a linear increase in thickness with planar orientation and a curvilinear increase in thickness with planar orientation.

4. The electrothermal film of claim 2, wherein the continuous transition is a transition region having a thickness gradient of no more than 100 microns/1000 microns.

5. The electrothermal film according to any one of claims 1 to 4, wherein the heat generating layer further comprises a blank region, the blank region being located within the heat generating region.

6. The electrothermal film according to claim 5, wherein the blank region is continuously transited to the heating region, and the blank region is continuously transited to the converging region.

7. The electrothermal film according to claim 5, wherein the heating area comprises a plurality of heating strips arranged at intervals, two ends of each heating strip are respectively provided with one confluence area, and the blank area is formed between two adjacent heating strips.

8. The electrothermal film according to claim 5, wherein the heating region has a plurality of through holes therein, and each of the through holes is the blank region.

9. an electrothermal product comprising the electrothermal film of any one of claims 1 to 8.