CN205430649U - Transparent electric heat membrane of low -voltage, high temperature electric heat piece - Google Patents

Abstract

The utility model discloses a low-voltage transparent electrothermal film, which comprises a transparent base material, a transparent conductive layer and electrodes; the transparent conductive layer is formed on at least one side of the transparent base material; The bus bars extend toward each other to form interdigitated electrodes; the electrodes are located on the transparent conductive layer and are in electrical contact with the transparent conductive layer. And it discloses a high-temperature electric heater, which includes a base material, a heating layer, and an electrode; the electrode structure is an interdigitated structure or two parallel strip structures. The utility model reduces the distance between the two electrodes by setting the bus bar and the inner electrode so that the resistance of the transparent conductive layer between the two electrodes is reduced, so that low voltage power supply can be used, and the daily lithium battery voltage can be used normally, that is, Can achieve rapid heating to 90-180°C. Two sets of electrodes can be arranged on both sides of the graphene, and the inner electrodes of the two sets of electrodes are staggered by a certain distance, which can further ensure the uniformity of heating and increase the heating temperature under the same low voltage.

Description

A low-voltage transparent electric heating film and a high-temperature electric heating sheet

technical field

The utility model relates to a transparent electric heating film, in particular to a low-voltage transparent electric heating film; at the same time, the utility model also relates to a high-temperature electric heating sheet; both the transparent electric heating film and the high-temperature electric heating sheet belong to the electric heating film field.

Background technique

The transparent heating film is usually coated with a transparent conductive coating on the surface of the film, and then a conductive electrode is made on the surface of the conductive coating. The electrodes are usually two parallel metal strips. The two metal strips are respectively connected to the positive and negative poles of the power supply. The current flows through the transparent conductive coating. The layer generates heat, as shown in Fig. 1 (referring to the patent whose publication number is CN103828482A). At present, the commonly used transparent conductive layers such as graphene, carbon nanotubes, ITO, FTO, AZO, etc. have a large sheet resistance when the film thickness is thin, which makes it necessary to use a high power supply voltage to meet the heating requirements, which is not conducive to the safety of the electrothermal film. and portability requirements; moreover, although increasing the thickness can reduce the operating voltage, it increases the material cost and reduces the production efficiency and light transmittance.

In the patent with the publication number CN102883486A and titled "A Graphene-Based Transparent Electric Heating Film and Its Preparation Method", the transparent electric heating film includes a transparent flexible substrate, a graphene film is arranged on the transparent flexible substrate, and the graphene film A conductive connecting mesh is arranged on the conductive connecting mesh, and electrodes are arranged on the conductive connecting mesh, and the electrodes are electrically connected with the conductive connecting mesh and the graphene film; a protective layer is arranged on the electrode, and the protective layer covers the electrodes, and covers the graphene film and the graphene film. Conductive connection to the omentum. This patent proposes to use graphene and conductive connection mesh as the transparent heating material of the electric heating film. This method can reduce the square resistance of the overall transparent conductive material through the conductive connection mesh, but has the following disadvantages:

1) The square resistance of the conductive connection film is usually much smaller than the square resistance of graphene, and the two are connected in parallel, so that the heating effect is mainly caused by the conductive connection film rather than graphene.

2) The wire diameter of the conductive connecting membrane is less than 5 μm, and it is easy to be burned when the conventional metal material is energized, so that the electric heating membrane fails.

A graphene flexible transparent heating element and its preparation method have also been proposed in the prior art. In order to enhance the uniformity of heating, a patterned transparent electrode is used, and the middle of the transparent electrode is connected to the electrode. However, patterned electrodes also use transparent conductive materials. Because transparent conductive materials have poor conductivity, it is difficult to obtain the effect of reducing the operating voltage after introducing patterned electrodes. Therefore, multi-layer (5-6 layers) graphene must be used to reduce resistance. Reduce the voltage used. In addition, if two parallel electrodes are used instead of patterned electrodes, the heating uniformity obtained is poor, and the difference between the highest point and the lowest point of temperature is more than 60K, which makes it difficult to meet the practical requirements.

Utility model content

In order to solve the problems in the prior art, the utility model provides a low-voltage transparent electrothermal film, which can work at low voltage (≤12V) to reach the expected temperature.

Further, the transparent electrothermal film has good heating uniformity.

Furthermore, the transparent electrothermal film is heated with a thinner transparent conductive layer. When graphene is used as the transparent conductive layer, a single layer of graphene can be used, and the electrothermal film can be obtained by using a very low voltage (such as ≤ 1.5V). It has the same heating effect as the traditional transparent electrothermal film, and it is the transparent conductive layer that generates heat.

In order to solve the aforementioned technical problems and achieve the above-mentioned technical effects, the utility model provides the following technical solutions:

A low-voltage transparent electrothermal film, comprising a transparent substrate, a transparent conductive layer, and electrodes; the transparent conductive layer is formed on at least one side of the transparent substrate; the electrodes are composed of bus bars and a number of internal electrodes, and the internal electrodes are formed by extending the bus bars toward each other Interdigitated electrodes; the electrodes are located on the transparent conductive layer and are in electrical contact with the transparent conductive layer.

Preferably, the electrodes are composed of a thick bus bar and several thin internal electrodes, the bus bar is connected to the positive or negative pole of the power supply, so that the polarity of the two adjacent internal electrodes is opposite, and the current provided by the positive bus bar is provided by each positive internal electrode Inflow into the corresponding negative electrode internal electrode and finally all into the negative electrode bus bar.

Preferably, one end of the bus bar is connected to the positive pole or the negative pole of the power supply.

Further preferably, two sets of positive and negative electrodes can be respectively arranged on both sides of the transparent conductive layer, and the inner electrodes of the two sets of electrodes are staggered by a certain distance, that is, the positive and negative interdigitated electrodes are respectively placed on both sides of the transparent conductive layer to form a transparent conductive layer. The interdigitated electrodes separated by layers ensure that the current passes through the transparent conductive layer evenly, which can further ensure the uniformity of heating.

Preferably, the material of the transparent conductive layer includes but not limited to graphene, carbon nanotubes, ITO, FTO, AZO and the like.

Preferably, the electrodes can be made of transparent conductive materials, wherein the preferred transparent electrode material is graphene.

Preferably, the electrodes are located on and integrally formed with the graphene layer.

Preferably, the electrode material includes but not limited to silver, silver paste, copper, copper paste, aluminum, ITO and other materials with good electrical conductivity. Copper foil is the best electrode material.

Preferably, electrodes may be formed between the transparent substrate and the transparent conductive layer.

Preferably, the transparent substrate can be glass or polymer, and the transparent substrate includes but not limited to PET, PVC, PE, PC and other films. More preferably, the polymer can be: PET, PMMA, PVDF, PANI, or a combination thereof.

Preferably, the transparent conductive layer is single-layer or multi-layer graphene. The best is single-layer graphene.

The electrode with special structure of the utility model is applied to single-layer graphene, which can make the transparent electrothermal film work at low voltage (≤12V), and lower voltage can be used on multi-layer graphene.

Preferably, the graphene layer can use a dopant; more preferably, the dopant can be an inorganic/organic dopant.

Preferably, a protective layer can be covered on the electrode and the graphene layer; more preferably, the protective layer can be made of a flexible transparent material.

Preferably, the material of the transparent cover layer includes but not limited to PET, PVC, PE, PC and other films.

Preferably, the electrodes of the present invention can be connected in series or in parallel.

Preferably, the transparent electrothermal films of the present invention can be connected in series or in parallel.

Further, the internal electrode is linear, wavy or zigzag, the bus bar can be linear or curved according to the shape and application requirements of the electrothermal film, and the pattern shape of the bus bar and the internal electrode is according to the shape of the electrothermal film. According to the shape and application requirements, it can also be surrounded by square, round, oval or any shape.

More preferably, the bus bar is located at the edge of the transparent conductive layer and is in good contact with the transparent conductive layer, the internal electrodes extend from one bus bar to another, and adjacent internal electrodes are from different bus bars and extend towards each other.

Further, the inventor of the utility model found that in order to obtain good temperature uniformity under low voltage, for the electrode with the special structure of the utility model, the final heating temperature, initial temperature, power supply voltage, distance between two inner electrodes and transparency The sheet resistance of the conductive layer conforms to the following formula:

T=kU ² /d ² R+t (1)

Where: the distance between the two internal electrodes is calculated according to the distance between the internal electrodes on one side of the transparent conductive layer,

t - initial temperature, in °C;

T——The final heating temperature of the electric heating film, the unit is ℃;

U——supply voltage, the unit is V, U≤12V;

d—internal electrode spacing, in cm;

R——the square resistance of the transparent conductive layer, the unit is Ω/□;

k——Constant, the value range is 10-200, the value range of k will be different according to the conduction coefficient between the electric heating film and the air, and it is inversely proportional to the conduction coefficient between the electric heating film and the air.

Using the electrode with special structure of the utility model reduces the resistance of the transparent conductive layer between the two electrodes by reducing the distance between the two internal electrodes, which is an optimal way, making it possible to use low voltage power supply. Normally, the daily lithium battery voltage can be used to achieve rapid heating.

Preferably, the bus bars and internal electrodes of the electrothermal film can be made of the same material or different materials, and the length thereof is designed according to the size of the electrothermal film. In order to ensure temperature uniformity, the width and thickness of the bus bar should consider the current carrying capacity and resistivity of the material used. The resistivity should be small enough to reduce the voltage drop on the bus bar and ensure that the internal electrodes are arranged at different positions on the bus bar. The difference between the highest voltage and the lowest voltage does not exceed 10%, and the current carrying capacity determines that the cross-sectional area of the bus bar must be greater than a certain value to ensure that the bus bar will not be burned. The inventor of the utility model finds that there is the following formula (2):

n(n+1)lρ _l /WHR＜1/5 (2)

in:

n——internal electrodes make a total of n intervals in the area surrounded by bus bars;

ρ ₁ ——resistivity of bus bar material, unit is Ω·m;

l——the length of each internal electrode, if the length is different, it is calculated according to the longest internal electrode, and the unit is m;

W——bus width, in m;

H——thickness of bus bar, in m;

R——sheet resistance of the transparent conductive layer, the unit is Ω/□.

Preferably, the internal electrodes ensure the current carrying capacity and consider that the maximum voltage difference on the same internal electrode does not exceed 10%. The inventor of the utility model finds that there is the following formula (3):

nl ² ρ ₂ /whLR<1/5 (3)

in:

n——internal electrodes make a total of n intervals in the area surrounded by bus bars;

l——the length of each internal electrode, if the length is different, it is calculated according to the longest internal electrode, and the unit is m;

ρ ₂ ——resistivity of internal electrode material, unit is Ω·m;

w—the width of the inner electrode, in m;

h - the thickness of the inner electrode, in m;

L——The total length generated from the first internal electrode to the last internal electrode on each bus bar, unit m;

R——sheet resistance of the transparent conductive layer, the unit is Ω/□.

The utility model reduces the resistance of the transparent conductive layer between the two electrodes by adopting electrodes with a special structure and reducing the distance between the two internal electrodes, so that low-voltage power supply can be used. Normally, the voltage of a lithium battery for daily use can be used. Achieve rapid heating to 90-180°C. Two sets of positive and negative electrodes can be placed on both sides of graphene to form interdigitated electrodes separated by graphene, which can further ensure the uniformity of heating and increase the heating temperature under the same low voltage.

For transparent conductive materials grown on metal foil substrates, a metal foil substrate with a transparent conductive film grown on the surface can be used to make patterned electrodes, which can simplify the preparation process, save time and material costs, and the metal foil has good conductivity , which is beneficial to the control of the temperature uniformity of the electrothermal film. The specific process is as follows:

1. Preparation of transparent conductive materials grown on metal foil substrates;

2. Adhere the transparent base material and the side of the metal foil on which the transparent conductive material grows;

3. Make a mask on the metal foil surface by photolithography or printing, and the mask pattern is designed according to the requirements;

4. Place the masked transparent substrate/transparent conductive layer/metal foil in the etching solution to etch away the metal not protected by the mask;

5. Remove the mask on the surface of the metal electrode to form a patterned electrode.

Further preferably, the transparent protective layer can be covered on the transparent conductive layer and the patterned electrode, and the specific steps are as follows:

6. Make a hole in the transparent protective layer with glue, so as to expose the electrode to be lead when it is attached to the lower electrode and the transparent conductive layer;

7. Align the holes of the transparent protective layer with the electrodes and stick them together;

8. Make lead wires at the electrodes exposed by the small holes.

Preferably, the transparent conductive material can be graphene.

Preferably, transparent glue is used to bond the transparent substrate and the side of the metal foil on which the transparent conductive material grows. More preferably, the transparent adhesive includes, but is not limited to, various UV curable resins, hot melt adhesives, silica gel and the like.

Preferably, the metal foil may be selected from but not limited to copper foil, nickel foil, copper-nickel alloy foil and the like.

Preferably, the etching solution is selected according to the metal foil, and substances that improve the conductivity of the transparent conductive material may be added to the etching solution.

Preferably, the method for removing the surface mask of the metal electrode can be a method of manual peeling or solution removal according to the mask material.

Preferably, the preparation method of a low-voltage transparent electrothermal film described in the present invention can also adopt the following steps:

1. Bond the transparent substrate and the transparent conductive layer together;

2. To make electrodes on the transparent conductive layer, it can be carried out by directly printing conductive paste or evaporating conductive materials, and the electrode pattern is designed according to heating requirements.

Further preferably, the protective layer can be covered on the transparent conductive layer and the electrodes, and the specific steps are as follows:

3. Make a hole in the transparent protective layer with glue, so as to expose the electrode to be lead when it is attached to the lower electrode and the transparent conductive layer;

4. Align the holes of the transparent protective layer with the electrodes and stick them together;

5. Make lead wires at the electrodes exposed by the small holes.

Beneficial effects of the utility model:

(1) Since the introduction of bus bars and internal electrodes reduces the electrode spacing of the transparent conductive layer, compared with the existing transparent electrothermal film electrode design scheme, a lower voltage can be used for power supply, so that lithium can be used Powered by a portable power source such as a battery.

(2) The electrode design of the thin inner electrode of the thick bus bar can use the transparent conductive material with poor conductivity under the same heating voltage condition, and obtain the same heating effect as the material with good conductivity by changing the inner electrode spacing.

(3) Under the condition of fixed power supply voltage and transparent conductive material, different heating power can be realized by controlling the bus bar area and the inner electrode spacing, so as to meet different heating temperature requirements.

(4) The process of making the electrode by patterning the metal foil simplifies the electrode manufacturing, improves the conductivity of the electrode, saves the manufacturing time, and reduces the material cost required for the manufacturing.

Another important purpose of the utility model is to provide a high-temperature electric heater, which uses carbon nanomaterials such as graphene or carbon nanotube film as a heating element, which can achieve more uniform and efficient heating, and can be connected to direct current or Can be connected to AC.

In the prior art, in the field of high-temperature heating sheets, the technology closest to this application is to use alloy wire or alloy foil as heating element for heating. These two heating methods have two disadvantages:

Poor heating uniformity. The heating of alloy wire or alloy foil is local heating, and the temperature distribution is uniform through the heat conduction plate, and the temperature uniformity is poor.

The heating efficiency is not high. The emissivity of the metal is small, and part of the electric energy is converted into electromagnetic waves when the spiral metal wire and the metal foil are energized when the AC power supply is applied.

In order to solve the aforementioned technical problems and achieve the above-mentioned technical effects, the utility model provides the following technical solutions:

A high-temperature electric heater, including a substrate, a heating layer, and an electrode; the heating layer is formed on at least one side of the substrate; the electrode structure is an interdigitated structure or two parallel strip structures; preferably, the utility model The electrodes are connected in series or in parallel.

As a preferred solution, the structure of the interdigitated electrodes is as follows:

It is composed of a thick bus bar and a number of thin internal electrodes. The bus bar is connected to the positive or negative pole of the power supply, so that the polarity of the two adjacent internal electrodes is opposite. The electrodes are finally all connected to the negative bus bar; preferably, one end of the bus bar is connected to the positive or negative pole of the power supply; further preferably, two sets of positive and negative electrodes can be arranged on both sides of the heating layer, and the inner electrodes of the two sets of electrodes are staggered by a certain distance , that is, the positive and negative interdigitated electrodes are respectively placed on both sides of the heating layer to form interdigitated electrodes separated by the heating layer to ensure that the current passes through the heating layer evenly, which can further ensure the uniformity of heating.

For the above-mentioned high-temperature electric heater, the final heating temperature, initial temperature, power supply voltage, distance between the two inner electrodes and the square resistance of the heating layer conform to the following formula:

T=kU ² /d ² R+t (4)

in:

t - initial temperature, in °C;

T——The final heating temperature of the electric heater, in °C;

U——supply voltage, the unit is V;

d—internal electrode spacing, in cm;

R——heating layer square resistance, the unit is Ω/□;

k——Constant, the value range is 10-200, the value range of k will be different according to the conduction coefficient between the heater and the air, and it is inversely proportional to the conduction coefficient between the heater and the air.

For the above-mentioned high-temperature electric heater, the setting of the bus bar should ensure that the difference between the highest voltage and the lowest voltage of the inner electrode at different positions of the bus bar does not exceed 10%, and the following formula (2) is satisfied:

n(n+1)lρ _l /WHR＜1/5 (5)

in:

n——internal electrodes make a total of n intervals in the area surrounded by bus bars;

ρ ₁ ——resistivity of bus bar material, unit is Ω·m;

l——the length of each internal electrode, if the length is different, it is calculated according to the longest internal electrode, and the unit is m;

W——bus width, in m;

H——thickness of bus bar, in m;

R——The heating layer square resistance, the unit is Ω/□.

For the above-mentioned high-temperature electric heater, the maximum voltage difference on the same internal electrode shall not exceed 10%, and the following formula (3) shall be satisfied:

nl ² ρ ₂ /whLR<1/5 (6)

in:

n——internal electrodes generate n intervals;

l——the length of each internal electrode, if the length is different, it is calculated according to the longest internal electrode, and the unit is m;

ρ ₂ ——resistivity of internal electrode material, unit is Ω·m;

w—the width of the inner electrode, in m;

h - the thickness of the inner electrode, in m;

L——The total length generated from the first internal electrode to the last internal electrode on each bus bar, the unit is m;

R——The heating layer square resistance, the unit is Ω/□.

As another preferred solution, two of the parallel electrodes are arranged on two edges of the heating layer. Preferably, the parallel electrodes are straight parallel electrodes, curved parallel electrodes or zigzag parallel electrodes.

Using a high-temperature electric heater with parallel electrodes, the final heating temperature, initial temperature, supply voltage, distance between two electrodes and the square resistance of the heating layer conform to the following formula:

T=kU ² /d ² R+t (7)

in:

t - initial temperature, in °C;

T——The final heating temperature of the electric heater, in °C;

U——supply voltage, the unit is V;

d——the distance between two parallel electrodes, in cm;

R——heating layer square resistance, the unit is Ω/□;

k——Constant, the value range is 10-200, the value range of k will be different according to the conduction coefficient between the heater and the air, and it is inversely proportional to the conduction coefficient between the heater and the air.

According to the application test, when the same voltage is connected, the electrode width is 7-10mm, and the distance between the two normal electrodes is 9-13cm. Under the condition that other factors of the heating plate remain unchanged, the heating speed is the fastest, and the temperature can be raised to within 15 minutes. Above 250°C. The most optimal solution is parallel electrodes with an electrode width of 8mm and a spacing of 10cm. When a high voltage is connected, the temperature can be raised to above 250°C within 10 minutes.

Further, the above-mentioned high-temperature electric heater, the material of the heating layer is a single-layer or multi-layer graphene, or a carbon nanotube film, preferably a single-layer or multi-layer graphene, more preferably 3-5 layers of graphene; preferably , the graphene can use doped graphene; more preferably, its dopant can be an inorganic/organic dopant;

And/or, the substrate is a high temperature resistant material, preferably polyimide film, glass-ceramic, quartz glass, borosilicate glass, sapphire or ceramic material; more preferably glass-ceramic, quartz glass or ceramic material; preferably Yes, the thickness of the substrate is 20-5000 μm, such as 20 μm, 50 μm, 100 μm, 200 μm, 300 μm, 400 μm, 500 μm, 1000 μm, 1700 μm, 2500 μm, 3000 μm, 3200 μm, 4000 μm, 4600 μm, 5000 μm, etc., all are acceptable; more preferably Yes, the thickness of the substrate is 50-3000 μm, such as 50 μm, 200 μm, 300 μm, 450 μm, 550 μm, 700 μm, 1000 μm, 1300 μm, 1800 μm, 2000 μm, 2400 μm, 2600 μm, 3000 μm, etc., are all available. Although the thickness of the base material can reach thousands of microns, the temperature of the high-temperature electric heater of the utility model can also reach more than 300 degrees.

And/or, the electrode material is a material with good electrical conductivity and high temperature resistance, preferably silver, silver paste, copper, copper paste or aluminum; more preferably silver paste; preferably, the silver paste is high temperature resistant conductive silver paste, The sintering temperature of the high-temperature-resistant conductive silver paste is above 300°C, for example: 350°C, 380°C, 410°C, 440°C, 470°C, 500°C, 530°C, 570°C, 600°C, 650°C, 680°C, etc. .

Preferably, the electrode and the heating layer of the high-temperature electric heater are provided with a covering layer, and the heating layer provided with the electrode is sandwiched between the heating layer corresponding to the base material; preferably, the material of the covering layer is a high-temperature-resistant material, Preferably it is polyimide film or glass glaze; the most optimal is glass glaze.

Preferably, the thickness of the covering layer is 1-1000 μm, such as 1 μm, 10 μm, 40 μm, 75 μm, 100 μm, 133 μm, 157 μm, 200 μm, 260 μm, 300 μm, 350 μm, 400 μm, 440 μm, 500 μm, 550 μm, 584 μm, 620 μm, 700 μm , 750 μm, 800 μm, 830 μm, 880 μm, 900 μm, 960 μm, 1000 μm, etc.; further preferably, the thickness of the covering layer is 5-200 μm, such as 5 μm, 7 μm, 15 μm, 20 μm, 45 μm, 60 μm, 90 μm, 110 μm, 140 μm, 155 μm, 160μm, 175μm, 200μm, etc. The cover layer is also called the cover protection layer, which is used to fix and protect the thinner heater and electrode, so that the combination between the heater and the electrode is more firm, and at the same time, the heater and the electrode are isolated from the outside world to avoid contamination or external force. deformation etc. When the protective layer is too thin, such as less than 75 μm, as the thickness of the covering layer decreases, the protective effect of the electrode and the heating layer under long-term high temperature will be relatively weakened, and it is easy to cause micro-deformation of the electrode. It has been found through research that when the thickness of the covering protective layer is less than 75 μm, the heating time for the deformation of the electrode decreases sharply as the thickness decreases. long-term stable state. When the covering protective layer is too thick, it will affect the conduction of the temperature of the electric heating layer in the heating sheet, and affect the final temperature of the electric heating sheet. After in-depth research, it is found that when the covering layer adopts 75-123μm glass glaze, the stability of the electrode of the high-temperature electric heater and the temperature conduction of the covering layer are in the best state. For example: 75μm, 78μm, 81μm, 86μm, 90μm, 92μm, 95μm, 97μm, 103μm, 108μm, 111μm, 115μm, 119μm, 121μm, 123μm, etc. At this time, the temperature is kept at 300°C for 720h, and the electrode does not have any deformation. The performance of the chip has no abnormal change, and the temperature conduction is good.

The preparation process of the high-temperature electric heater comprises the following steps:

1) Prepare the heating layer material grown on the metal foil substrate;

2) Bonding the substrate and the side of the metal foil on which the heating layer material is grown;

3) Make a mask on the metal foil surface by photolithography or printing, and design the mask pattern as required;

4) Place the masked substrate/heating layer/metal foil in the etching solution to etch away the metal not protected by the mask;

5) removing the mask on the surface of the metal electrode to form a patterned electrode;

Alternatively, electrodes can be made by directly printing conductive paste or evaporating conductive material on the heating layer, preferably direct printing conductive metal paste;

Preferably, when the method of printing electrodes with conductive metal paste is used to make a high-temperature heating sheet, it specifically includes the following steps:

1) transferring the heating layer to the substrate;

2) Make electrodes on the heating layer by directly printing conductive paste or evaporating conductive materials, and the electrode pattern is designed according to requirements;

Further preferably, the above two different preparation methods are also prepared with a covering layer, and the specific operations are as follows:

Print or coat the covering layer on the finished heating layer with electrodes, preferably, the thickness of printing or coating is 1-1000 μm, preferably 5-200 μm, and the best printing or coating is 75-123 μm.

The above scheme has the following advantages:

The high-temperature electric heater of the utility model replaces the currently used alloy heating wire or alloy heating foil by using carbon nanomaterials such as graphene and carbon nanotube film, and at the same time optimizes the material matched with the heating element, and can also carry out special electrode design according to needs , to achieve more uniform and efficient heating. Specifically, the following two points:

(1) Improved heating uniformity. When the high-temperature electric heating sheet of the utility model is used for heating, it is different from the previous alloy wire and alloy foil. The conductive film (that is, the heating layer) in the entire surface is all heated, which improves the temperature uniformity, and the entire high-temperature electric heating sheet is stable. The difference between the highest surface temperature and the lowest temperature is less than 10K;

(2) High heating efficiency. The utility model uses carbon nanomaterials such as graphene and carbon nanotube film for heating, and can quickly convert electric energy into heat energy in a short period of time. The heating efficiency is very high. Generally, under the voltage of 220V, it can reach stability within 9-15 minutes of electrification. After stabilization, the temperature can reach above 400°C.

(3) Long service life. The high-temperature heating sheet of the utility model is different from the existing metal wire or alloy heating foil. Under the voltage of 220V, it is easy to age or short-circuit when working for a long time. Carbon nanomaterials such as graphene and carbon nanotube film are used as the heating layer for electrothermal conversion. It overcomes the material aging problem caused by long-term electric heating. At the same time, the combined design of the electrode, heating layer and covering layer forms a firm body. Not only is the heat energy easy to release, but the electrode is also not easy to be burned by high voltage, which improves the high-temperature electric heating film. The service life can reach more than 30,000 hours of continuous work at 220V to maintain high-efficiency heating, and intermittent power can achieve more than 100,000 times without affecting performance.

Description of drawings

The accompanying drawings are used to provide a further understanding of the utility model, and constitute a part of the description, and are used to explain the utility model together with the embodiments of the utility model, and do not constitute a limitation to the utility model. In the attached picture:

Fig. 1 is the arrangement figure of transparent heating membrane electrode in the background technology;

Fig. 2 is the electrode distribution figure of the electrothermal film of the utility model embodiment 1;

Fig. 3 is a sectional view of a preferred embodiment of the utility model;

Fig. 4 is the electrode distribution figure of the electrothermal film of the utility model embodiment 2;

Fig. 5 is the electrode distribution diagram of the electrothermal film of the utility model embodiment 3;

Fig. 6 is the electrode distribution diagram of the electrothermal film of the utility model embodiment 4;

Fig. 7 is the temperature distribution photograph that the electric heating film (non-optimal scheme) infrared camera of embodiment 1 of the utility model is taken;

Fig. 8 is the temperature distribution photograph that the electrothermal film (optimal solution) infrared camera of embodiment 1 of the present invention takes;

Fig. 9 is a straight-line temperature distribution diagram of the electric heating film (optimal solution) of the utility model embodiment 1, the horizontal mark is the position representation of the electric heating film from left to right, and the vertical mark is the temperature;

Fig. 10 is the temperature distribution photograph that the electric heating film (non-optimal scheme) infrared camera of embodiment 2 of the present invention is taken;

Fig. 11 is the temperature distribution photograph that the electric heating film (preferred solution) infrared thermal imager of the utility model embodiment 2 takes;

Fig. 12 is a straight-line temperature distribution diagram of the electric heating film (preferred solution) in Example 2 of the present utility model, the horizontal mark is the position representation of the electric heating film from left to right, and the vertical mark is the temperature;

Fig. 13 is a linear temperature distribution diagram of the electrothermal film in Example 3 of the present invention;

Fig. 14 is a linear temperature distribution diagram of the electrothermal film in Example 4 of the utility model;

Fig. 15 is a linear temperature distribution diagram of the electrothermal film in Embodiment 5 of the present invention;

Fig. 16 is a linear temperature distribution diagram of the electrothermal film in Embodiment 6 of the present invention;

Fig. 17 is a linear temperature distribution diagram of the electrothermal film in Example 7 of the present utility model;

Fig. 18 is a linear temperature distribution diagram of the electrothermal film in Embodiment 8 of the present utility model;

Fig. 19 is a linear temperature distribution diagram of the electrothermal film in Embodiment 9 of the present invention;

Fig. 20 is a linear temperature distribution diagram of the electrothermal film in Embodiment 10 of the present utility model;

Fig. 21 is a linear temperature distribution diagram of the electrothermal film in Example 11 of the present utility model;

Fig. 22 is a photo of the temperature distribution taken by the high-temperature electric heater infrared thermal imager of Embodiment 14 of the present invention;

Fig. 23 is a photo of the temperature distribution taken by the high-temperature electric heater infrared thermal imager of Embodiment 15 of the present invention;

Fig. 24 is a photo of temperature distribution taken by the high-temperature electric heater infrared thermal imager of Embodiment 16 of the present invention;

Fig. 25 is a photo of the temperature distribution taken by the high-temperature electric heater infrared thermal imager of Embodiment 17 of the present invention;

Fig. 26 is a photo of the temperature distribution taken by the high-temperature electric heater infrared thermal imager of Embodiment 18 of the present invention;

Fig. 27 is a photo of the temperature distribution taken by the high-temperature electric heater infrared thermal imager of Embodiment 19 of the present invention;

Fig. 28 is a photo of the temperature distribution taken by the high-temperature electric heater infrared thermal imager of Embodiment 20 of the present invention;

Fig. 29 is a photo of the temperature distribution taken by the high-temperature electric heater infrared thermal imager of Embodiment 21 of the present invention;

Fig. 30 is a photo of the temperature distribution taken by the high-temperature electric heater infrared thermal imager of Embodiment 22 of the present invention;

Among the figure, 1--transparent conductive layer (heating layer in the high-temperature electric heating sheet of embodiment 14-30), 2--electrode, 21--bus bar, 22-internal electrode, 3--transparent substrate (in In the high-temperature electric heating sheet of embodiment 14-30 be base material, it also can be opaque material), 4---transparent covering layer (in embodiment 14-30 high-temperature electric heating sheet is covering layer, and it also can be opaque material) .

detailed description:

The preferred embodiments of the present utility model are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described here are only used to illustrate and explain the present utility model, and are not intended to limit the present utility model.

In the following embodiments, although the numerical values all satisfy the three formulas at the same time, for the patterned electrode of the thick bus bar and the thin inner electrode, as long as the parameters satisfy at least any one of the formulas, the utility model purpose of the present utility model can be realized, and the utility model can be solved. New technical problems to be solved. In the embodiment, only the implementation manner satisfying the three formulas is given, but it will not constitute any limitation to the technical solution of the utility model.

The resistivity of the materials involved in the following examples are well known in the art, for example, the resistivity of copper is 1.75×10 ^-8 Ω·m, the resistivity of silver paste is 8×10 ^-8 Ω·m, graphene (single layer) 1×10 ^-8 Ω·m.

Example 1:

Referring to Figures 2 and 3, single-layer graphene is used as a low-voltage transparent electrothermal film for heating components, and the electrodes are printed with silver paste.

The preparation process is as follows:

1. Transfer a layer of graphene on a PET (transparent substrate) with an area of 150mm×150mm and a thickness of 125μm. The graphene has been doped and the square resistance is 250Ω/□;

2. Use screen printing equipment to print the silver paste electrode pattern on the transferred graphene. The shape of the pattern is shown in Figure 2. The internal electrode spacing is 6mm, the width is 1mm, and the thickness of the silver paste is 25μm;

3. Bake the printed electrode pattern in an oven to solidify the silver paste. The baking temperature is 130°C for 40 minutes.

The initial temperature is room temperature (22°C). In this case, connect the lead wires to the positive and negative poles of the 5V power supply respectively. After testing, it can reach a stable state in 60 seconds. Figure 7 shows the temperature distribution taken by an infrared thermal imager In the photo, the average temperature of the electrothermal film can reach about 77.5°C at this time (the room temperature is 22°C). It conforms to the formula T=kU ² /d ² R+t (K=200).

The test results show that using our utility model electrode design scheme, the average heating power of the heating film is about 1500w/ ^m2 when the voltage is 3.7V, while the average heating power of the traditional electric heating film without internal electrodes is used when the voltage is 3.7V It is about 5.4w/m ² , to achieve the same heating effect as our newly designed electric heating film, the voltage needs to be increased to about 612V, which has far exceeded the safe voltage of the human body.

Preferably, the following steps are further carried out:

4. Lay OCA glue with an area of 150mm×150mm and a thickness of 50μm with PET of the same area;

5. Use laser cutting equipment to open a square hole in the bonded PET/OCA. The size of the hole is 5mm×5mm. The position of the hole should ensure that after the PET/OCA is bonded to the electrode pattern, a 5mm×5mm hole is exposed at the end of the bus bar. electrode;

6. After aligning the position, attach the PET/OCA to the electrode pattern;

7. Make lead wires from the electrodes exposed in the small holes;

In this case, the measured resistance of the electric heating film is 2.7Ω. Connect the lead wires to the positive and negative poles of the 5V power supply respectively. After testing, it can reach a stable state in 60 seconds. Figure 8 shows the temperature distribution taken by the infrared thermal imager The photo, Figure 9 shows the linear temperature distribution diagram. At this time, the average temperature of the electrothermal film can reach about 66°C (room temperature is 22°C), which conforms to the formula T=kU ² /d ² R+t(k=158) if the voltage The average temperature after stabilizing at 3.7V is 42°C, and if the voltage is stable at 7.4V, the average temperature is 103°C, which conforms to the formula T=kU ² /d ² R+t(k=133).

The test results show that using our utility model electrode design scheme, the average heating power of the heating film is about ^1300w /m2 when the voltage is 3.7V, while the average heating power of the traditional electric heating film without internal electrodes is used when the voltage is 3.7V It is about 5w/m ² , to achieve the same heating effect as our newly designed electric heating film, the voltage needs to be increased to about 60V, which has far exceeded the safe voltage of the human body.

The structure of the finally obtained transparent electrothermal film is: the core of the utility model is formed by the close bonding of the transparent conductive layer (single-layer graphene) 1 and the electrode 2, and the electrode 2 is composed of a bus bar 21 and an internal electrode 22 to form an interdigital electrode , the internal electrode spacing is 6mm, the width is 1mm, and the thickness of the silver paste is 25μm. The transparent base material 3 and the cover layer 4 sandwich the transparent conductive layer and the electrodes, and play the role of support, fixation and protection.

Example 2:

In this embodiment, two layers of graphene are used as the low-voltage transparent electrothermal film of the heating member, and the electrodes are printed with silver paste.

1. Transfer two layers of graphene on a PET (transparent substrate) with an area of 120mm×120mm and a thickness of 125μm. The graphene has been doped and the square resistance is 120Ω/□;

2. Use screen printing equipment to print the silver paste electrode pattern on the transferred graphene. The shape of the pattern is shown in Figure 4. The outer diameter of the bus bar is 96mm, the longest internal electrode is 73mm, and the distance between the internal electrodes is 6mm. 17 intervals, width 1mm, bus bar width 8mm, the length from the first internal electrode to the last internal electrode on the bus bar is 130mm, and the thickness of silver paste is 25μm;

3. Bake the printed electrode pattern in an oven to solidify the silver paste. The baking temperature is 130°C for 40 minutes.

In this case, connect the lead wires to the positive and negative poles of the 5V power supply respectively. After testing, it can reach a stable state in 60 seconds. Figure 10 shows the temperature distribution photos taken by the infrared thermal imager. At this time, the average temperature of the electric heating film can be It reaches about 137.7°C (the initial temperature is 22°C at room temperature), which conforms to the formula T=kU ² /d ² R+t (K=200).

The test results show that with our utility model electrode design scheme, the average heating power of the heating film is about ^3168w /m2 when the voltage is 3.7V, while the average heating power of the traditional electric heating film without internal electrodes is used when the voltage is 3.7V It is about 11.4w/m ² , to achieve the same heating effect as our newly designed electric heating film, the voltage needs to be increased to about 616.6V, which has far exceeded the safe voltage of the human body.

Preferably, the following steps are further carried out:

4. Lay OCA glue with an area of 120mm×120mm and a thickness of 50μm with PET of the same area;

5. Use laser cutting equipment to open a square hole in the bonded PET/OCA. The size of the hole is 5mm×5mm. The position of the hole should ensure that after the PET/OCA is bonded to the electrode pattern, a 5mm×5mm hole is exposed at the end of the bus bar. electrode;

6. After aligning the position, attach the PET/OCA to the electrode pattern;

7. Make lead wires from the electrodes exposed in the small holes;

In this case, the measured resistance of the electric heating film is 2Ω. Connect the lead wires to the positive and negative poles of the 5V power supply respectively. After testing, it can reach a stable state in 40 seconds. See Figures 11 and 12. At this time, the average temperature of the electric heating film It can reach about 90.9°C (room temperature is 22°C). According to the formula T=kU ² /d ² R+t(k=119.1)

The test results show that using our utility model electrode design scheme, the average heating power of the heating film is about ^1300w /m2 when the voltage is 3.7V, while the average heating power of the traditional electric heating film without internal electrodes is used when the voltage is 3.7V It is about 5w/m ² , to achieve the same heating effect as our newly designed electric heating film, the voltage needs to be increased to about 60V, which has far exceeded the safe voltage of the human body.

After testing, the difference between the highest voltage and the lowest voltage at different positions of the bus bar is 0.2%, and the maximum voltage difference on the inner electrode does not exceed 0.004%.

The structure of the finally obtained transparent electrothermal film is basically the same as that of Example 1, the difference is that the transparent conductive layer is double-layer graphene, and the shape surrounded by the electrodes is circular as shown in Figure 4, the outer diameter of the bus bar is 96mm, and the longest inner electrode is 73mm, the internal electrode spacing is 6mm, a total of 17 intervals are generated, the width is 1mm, the width of the bus bar is 8mm, the length from the first internal electrode to the last internal electrode on the bus bar is 130mm, and the thickness of the silver paste is 25μm.

Example 3:

Referring to Figure 5, the low-voltage transparent electrothermal film with single-layer graphene as the heating member is prepared as follows:

1. Lay the copper foil with the grown graphene (graphene is doped, the square resistance is 250Ω/□) and the PET with the size of 150mm×300mm and the thickness of 125μm through UV glue, and the size of the copper foil is 140mm×280mm , with a thickness of 25 μm;

2. Curing the UV glue with a wavelength of 365nm and an energy of 1000mJ/cm ² ;

3. Use screen printing equipment to print a peelable mask on the bonded copper foil. The pattern shape is shown in Figure 5. At this time, it is equivalent to the electric heating film being divided into two, forming two left and right electric heating films connected in series The actual utilization voltage is halved, the internal electrode spacing is 3mm, the length is 108mm, and the width is 1mm. There are 32 strips in total, and a total of 30 intervals are generated. The width of the bus bar is 8mm. On the bus bar, the first inner electrode goes to the last. The length of an internal electrode stop is 100mm, and the thickness of copper foil is 25μm;

4. Bake the printed electrode pattern in an oven to cure the peelable glue. The baking temperature is 135°C for 40 minutes;

5. The baked sample is etched in 30% FeCl ₃ etching solution. After the etching is completed, it is washed with water and dried, and the peelable glue on the electrode surface is peeled off.

In this case, the measured resistance of the electric heating film is 1.7Ω, and the lead wires are respectively connected to the positive and negative electrodes of the 3.7V lithium-ion battery (1.85V compared to half of the electric heating film). After testing, the temperature of the electric heating film can be stabilized after 30S. It reaches about 46°C, as shown in Figure 13, (the room temperature is 22°C), which conforms to the formula T=kU ² /d ² R+t (K=160).

The test results show that using the electrode design scheme of the present utility model, the average heating power of the heating film is about 1521w/m when using 3.7V voltage (the voltage actually applied to the ^two electrodes is 1.85V) to supply power, and when the voltage is 3.7V Using the traditional electric heating film without internal electrodes, to achieve the same heating effect as our newly designed electric heating film, the voltage needs to be increased to about 616V, which has far exceeded the safe voltage of the human body.

Preferably, the following steps are further carried out:

6. Lay OCA glue with an area of 150mm×300mm and a thickness of 50μm with PET of the same area;

7. Use laser cutting equipment to open a square hole in the bonded PET/OCA. The size of the hole is 5mm×5mm. The position of the hole should ensure that after the PET/OCA is bonded to the electrode pattern, a 5mm×5mm hole is exposed at the end of the bus bar. electrode;

8. After aligning the position, attach the PET/OCA to the electrode pattern;

9. Make lead wires from the electrodes exposed in the small holes;

The measured resistance of the electric heating film is 2.5Ω, and the lead wires are respectively connected to the positive and negative electrodes of the 3.7V (actually used voltage is equivalent to 1.85V) lithium-ion battery. After testing, the temperature of the electric heating film can reach about 45°C after 70S stabilization (room temperature is 22°C), conforming to the formula T=kU ² /d ² R+t (K=151).

After testing, the difference between the highest voltage and the lowest voltage at different positions of the bus bar is 0.2%, and the maximum voltage difference on the inner electrode does not exceed 0.004%.

The structure of the finally obtained transparent electrothermal film is basically the same as that of Example 1, the difference is that the shape of the electrodes is as shown in Figure 5, which can form the effect of connecting two electrothermal films on the left and right in series, the actual utilization voltage is halved, and the distance between the internal electrodes is 3mm, the length 108mm, 1mm wide, 32 strips in total, 30 intervals are generated in total, the width of the bus bar is 8mm, the length from the first internal electrode to the last internal electrode on the bus bar is 100mm, and the thickness of copper foil is 25μm. The electrode material is copper foil.

Example 4:

In this embodiment, ITO thin film is used as the low-voltage transparent electrothermal film of the heating member, and the silver paste is used as the electrode. The pattern design refers to Figure 2. The preparation process is as follows:

1. Use screen printing equipment to print the silver paste electrode pattern on the ITO film (square resistance 400Ω/□) with a square resistance of 150mm×150mm and a square resistance of 150Ω. The shape of the pattern is shown in Figure 2, and the distance between the internal electrodes 6mm, length 108mm, width 1mm, a total of 15 strips, 15 intervals are produced, the width of the bus bar is 8mm, and the thickness of the silver paste is 25μm;

2. Bake the printed electrode pattern in an oven to solidify the silver paste. The baking temperature is 130°C for 40 minutes.

3. Lay OCA glue with an area of 150mm×150mm and a thickness of 50μm with PET of the same area;

4. Use laser cutting equipment to open a square hole in the bonded PET/OCA. The size of the hole is 5mm×5mm. The position of the hole should ensure that after the PET/OCA is bonded to the electrode pattern, a 5mm×5mm hole is exposed at the end of the bus bar. electrode;

5. After aligning the position, attach the PET/OCA to the electrode pattern;

6. Make lead wires from the electrodes exposed in the small holes;

In this case, the measured resistance of the electric heating film is 5Ω. Connect the lead wires to the positive and negative poles of the 12V power supply respectively. After testing, it can reach a stable state in 55 seconds. See Figure 14. At this time, the average temperature of the electric heating film can reach about 92°C (The room temperature is 22°C), which conforms to the formula T=kU ² /d ² R+t (K=70).

After testing, the difference between the highest voltage and the lowest voltage at different positions of the bus bar is 0.05%, and the maximum voltage difference on the inner electrode does not exceed 0.01%.

The structure of the finally obtained transparent electrothermal film is basically the same as that of Example 1, the difference is that the transparent conductive layer is an ITO film, the inner electrode spacing is 6mm, the length is 108mm, and the width is 1mm. There are 15 strips in total, and 15 intervals are generated in total. The width of the bus bar is 8mm. The thickness of silver paste is 25μm.

Example 5:

In this embodiment, the transparent conductive layer adopts single-layer graphene (250Ω/□), and the electrode adopts 10 layers of graphene. During preparation, refer to the preferred method of embodiment 1, the difference is that the graphene film is continuously transferred to the graphene film transfer to the 11th layer, stop the transfer, and then etch the top 10 layers of graphene into a patterned electrode, or directly grow multi-layer graphene, and then make a patterned electrode. The pattern design of the electrode in this embodiment See attached drawing 2, the distance between internal electrodes is 3mm, the length is 108mm, and the width is 1mm. There are 15 strips in total, and 15 intervals are generated in total. The length is 60mm, and the electrode (10-layer graphene) is 35nm thick.

In this case, the measured resistance of the electric heating film is 2Ω. Connect the lead wires to the positive and negative poles of the 1.5V power supply respectively. After testing, it can reach a stable state in 85 seconds. See Figure 15. At this time, the average temperature of the electric heating film can reach 34°C About (room temperature is 22°C), conforms to the formula T=kU ² /d ² R+t (K=120).

After testing, the difference between the highest voltage and the lowest voltage at different positions of the bus bar is 0.1%, and the maximum voltage difference on the inner electrode does not exceed 0.02%.

The structure of the finally obtained transparent electrothermal film is basically the same as in Example 1, the difference is that the distance between the internal electrodes is 3 mm, the length is 108 mm, and the width is 1 mm. The length from one internal electrode to the last internal electrode is 60mm, and the thickness of the electrode (10 layers of graphene) is 35nm.

Embodiment 6:

This embodiment adopts 4 layers of graphene (62.5Ω/□) as the transparent conductive layer, and the electrode adopts ITO. During preparation, according to the preferred mode of embodiment 1, the difference is: adopt ITO to be printed on the time-transmitting conductive layer, The electrode pattern design is shown in Figure 4. The internal electrode spacing is 4mm, the width is 1mm, and there are 16 strips in total, resulting in 17 intervals. The width of the bus bar is 8mm, and the thickness of the silver paste is 25μm.

In this case, the measured resistance of the electric heating film is 0.4Ω. Connect the lead wires to the positive and negative electrodes of the 3.7V power supply respectively. After testing, it can reach a stable state in 100 seconds. See Figure 16. At this time, the average temperature of the electric heating film can reach 103 °C (room temperature is 22 °C), conforming to the formula T=kU ² /d ² R+t (K=110.9).

After testing, the difference between the highest voltage and the lowest voltage at different positions of the bus bar is 3%, and the maximum voltage difference on the inner electrode does not exceed 1.2%.

The structure of the finally obtained transparent electrothermal film is basically the same as in Example 1, the difference is that the internal electrode spacing is 4mm, and the width is 1mm, 16 in total, producing 17 intervals, bus bar width 8mm, silver paste thickness 25 μm, 4 layers of graphene ( 62.5Ω/□) as a transparent conductive layer.

Embodiment 7:

This embodiment is basically the same as the preferred solution of Embodiment 3, the difference is that the electrode pattern design is shown in Figure 2, the internal electrode spacing is 3 mm, the length is 108 mm, and the width is 1 mm. There are 15 lines in total, and a total of 15 intervals are generated. Width 8mm, copper foil thickness 25μm.

In this case, the measured resistance of the electric heating film is 1.7Ω. Connect the lead wires to the positive and negative poles of the 12V power supply respectively. After testing, it can reach a stable state in 100 seconds. See Figure 17. At this time, the average temperature of the electric heating film can reach 226°C About (room temperature is 22°C), conforms to the formula T=kU ² /d ² R+t (K=32).

After testing, the difference between the highest voltage and the lowest voltage at different positions of the bus bar is 0.9%, and the maximum voltage difference on the inner electrode does not exceed 0.1%.

Embodiment 8:

This embodiment is basically the same as the non-optimal solution of Embodiment 1, the difference is that the electrodes are formed between the transparent conductive layer and the transparent substrate, and the electrodes are made of copper foil. Refer to Figure 4 for the graphic design, and the distance between the internal electrodes is 2mm. The length is 108mm, the width is 1mm, and there are 16 strips in total, resulting in 17 intervals. The width of the bus bar is 8mm, and the thickness of the copper foil is 25μm. The square resistance of the transparent conductive layer made of single-layer graphene is 250Ω/□.

In this case, the measured resistance of the electric heating film is 2Ω. Connect the lead wires to the positive and negative poles of the 3.7V power supply respectively. After testing, it can reach a stable state in 30 seconds. See Figure 18. At this time, the average temperature of the electric heating film can reach 143.8°C About (room temperature is 22°C), conforms to the formula T=kU ² /d ² R+t (K=89).

After testing, the difference between the highest voltage and the lowest voltage at different positions of the bus bar is 0.04%, and the maximum voltage difference on the inner electrode does not exceed 3%.

Embodiment 9:

In this embodiment, the positive electrode and the negative electrode of the patterned electrode are separately arranged on both sides of the transparent conductive layer to form interdigitated electrodes separated by the transparent conductive layer. Layer graphene (resistance is 250Ω/□), the electrode adopts 5-10 layers of graphene or copper foil with a thickness of 10-30 μm, and the present embodiment preferably adopts 5-10 layers of graphene as electrode material, wherein, The distance between positive and negative adjacent internal electrodes is 4mm, the length is 108mm, and the width is 1mm. There are 15 strips in total, resulting in 15 intervals. The width of the bus bar is 8mm.

In this case, the measured resistance of the electric heating film is 2.1Ω. Connect the lead wires to the positive and negative poles of the 7.5V power supply respectively. After testing, it can reach a stable state in 30 seconds. See Figure 19. At this time, the average temperature of the electric heating film can reach 210 °C (room temperature is 22 °C), conforming to the formula T=kU ² /d ² R+t (K=134).

After testing, the difference between the highest voltage and the lowest voltage at different positions of the bus bar is 7%, and the maximum voltage difference on the inner electrode does not exceed 4%.

Example 10:

This embodiment is basically the same as Embodiment 3, except that the pattern design uses Figure 6, the transparent conductive layer uses 6 layers of graphene (square resistance is 41.6Ω/□), and the electrode is copper foil. The distance between the internal electrodes is 10mm, the width is 1mm, and there are 9 strips in total, resulting in 9 intervals. The width of the bus bar is 8mm, and the thickness of the copper foil is 25μm.

In this case, the measured resistance of the electric heating film is 0.32Ω. Connect the lead wires to the positive and negative poles of the 7.5V power supply respectively. After testing, it can reach a stable state in 30 seconds. See Figure 20. At this time, the average temperature of the electric heating film can reach 86.3 °C (room temperature is 22 °C), conforming to the formula T=kU ² /d ² R+t (K=47.6).

After testing, the difference between the highest voltage and the lowest voltage at different positions of the bus bar is 2.4%, and the maximum voltage difference on the inner electrode does not exceed 0.3%.

Example 11:

This embodiment is basically the same as Embodiment 1, except that the internal electrodes and the bus bars are made of different materials. The transparent conductive material can be used as the inner electrode, and the metal material can be used as the bus bar; or different metal materials can be used as the inner electrode and the bus bar respectively; or the transparent conductive material can be used as the bus bar, and the metal material can be used as the inner electrode. In this embodiment, metal copper foil or silver paste is preferably used as the material of the bus bar, and graphene with at least 5 layers is used as the material of the internal electrodes. In this embodiment, it is more preferable to use metal platinum as the material of the bus bar and 10-layer graphene as the material of the internal electrodes. Single-layer graphene is used as the material of the transparent conductive layer (square resistance is 250Ω/□). Refer to Figure 2 for the pattern design. The graphene internal electrode spacing is 5 mm, the length is 108 mm, and the width is 1 mm. There are 32 bars in total. The bus bar is 8 mm wide and 25 μm thick.

In this case, the measured resistance of the electric heating film is 1.9Ω. Connect the lead wires to the positive and negative poles of the 12V power supply respectively. After testing, it can reach a stable state in 30 seconds. See Figure 21. At this time, the average temperature of the electric heating film can reach 243°C About (room temperature is 22°C), conforms to the formula T=kU ² /d ² R+t (K=96).

After testing, the difference between the highest voltage and the lowest voltage at different positions of the bus bar is 1.5%, and the maximum voltage difference on the inner electrode does not exceed 2.3%.

Example 12:

The process of this embodiment is the same as that of Embodiment 1, the difference lies in the specific design of the electrodes.

In order to ensure that the internal electrodes are arranged at different positions of the bus bar, the difference between the highest voltage and the lowest voltage does not exceed 10%. During the production of this embodiment, the number of intervals n generated by the internal electrodes, the longest length l of the internal electrodes, and the width W of the bus bar 1. The thickness H of the bus bar is measured and processed accurately, so that it conforms to the above formula (2).

This embodiment requires that the electrodes be arranged as follows: the length of the inner electrode is 108 mm, 15 intervals are generated in total, the width of the bus bar is 8 mm, and the thickness is 25 μm. After testing, the difference between the highest voltage and the lowest voltage at different positions of the bus bar is 0.2%.

Connect the lead wires to the positive and negative poles of the 1.5V power supply respectively. After testing, it takes 75 seconds to reach a stable state. At this time, the average temperature of the electric heating film can reach about 51°C (room temperature is 22°C).

Example 13:

The process of this embodiment is the same as that of Embodiment 1, the difference lies in the specific design of the electrodes.

In order to ensure that the maximum voltage difference on the internal electrodes does not exceed 10%, during the production of this embodiment, the number of intervals n generated for the internal electrodes, the longest length l of the internal electrodes, the width w of the internal electrodes, the width h of the internal electrodes, and the The length L from the first internal electrode to the last internal electrode is measured and processed accurately so that it conforms to the above formula (3).

This embodiment requires that the electrodes be set as follows: the length of the internal electrode is 108 mm, and there are 15 internal electrodes in total. The width of each internal electrode is 1 mm and the thickness is 25 μm. There are 15 intervals in total. The width of the bus bar is 8 mm. The length from one internal electrode to the last internal electrode is 99mm. After testing, the maximum voltage difference on the inner electrodes does not exceed 0.05%.

Connect the lead wires to the positive and negative poles of the 7.5V power supply respectively. After testing, it takes 60 seconds to reach a stable state. At this time, the average temperature of the electric heating film can reach about 77.4°C (room temperature is 22°C).

The internal electrodes in the above embodiments can be made into other shapes such as wavy or zigzag parallel to each other.

Example 14:

1. The square resistance of transferring three layers of graphene on the glass-ceramic with an area of 120mm×120mm and a thickness of 4mm is about 250Ω/□;

2. Use screen printing equipment to print silver paste electrode patterns on the transferred graphene. The pattern shapes are shown in Figures 1 and 3. 1 is the heating layer, 2 is the electrode, and electrode 2 is designed as a parallel electrode. The width of the two parallel electrodes is 8mm, the thickness of silver paste is 25μm, and the distance between the two electrodes is 10cm; 3 is the base material (it can be transparent or opaque), and 4 is the covering layer of the high-temperature electric heater (it can be transparent or opaque );

3. Bake the printed electrode pattern in an IR furnace at a temperature of 150°C for 10 minutes, and then sinter in a tunnel furnace at 550°C for 10 minutes;

4. Apply a layer of glass glaze on the glass sheet;

5. Sinter the glass glaze in the tunnel.

The structure of the obtained high-temperature electric heater is: the heating layer (three-layer graphene) 1 and the electrode 2 are closely bonded, and the electrode 2 is designed as a parallel strip distributed at both ends of the heating layer 1. The width of the two parallel electrodes is 8 mm, and the thickness of the silver paste is 25 μm. , the distance between the two electrodes is 10cm. The base material 3 and the covering layer 4 sandwich the transparent conductive layer and the electrodes, and play the role of support, fixation and protection. The thickness of the substrate 3 is glass-ceramics with a thickness of 4 mm, and the cover layer 4 is glass glaze with a thickness of 115 μm.

The measured resistance of the high-temperature electric heater is 250Ω. The lead wires are connected to a DC or AC power supply, and the voltage is adjusted to 220V. After about 9 minutes, the temperature rises to 250°C (room temperature 22°C) and remains stable, which conforms to the formula (7), where K The value is 117.8, and the temperature distribution image tested by the infrared thermal imaging camera is shown in Figure 22, and the temperature uniformity in the effective heating area is ±10K.

Example 15:

1. Pass the copper foil with grown graphene (graphene has been doped, the square resistance is 125Ω/□) and the polyimide film with a size of 150mm×150mm and a thickness of 125μm (high temperature resistance can reach above 400°C) Bonded together with UV glue, the size of the copper foil is 130mm×130mm, and the thickness is 25μm;

2. Curing the UV glue, the wavelength is 365nm, the energy is 1000mJ/cm2,

3. Use screen printing equipment to print a peelable mask on the bonded copper foil. The pattern shape is shown in Figure 2-3. 1 is the heating layer of the high-temperature electric heating sheet that constitutes the core functional part of the utility model, 2. 21 is the bus bar, 22 is the internal electrode, 3 is the base material (it can be transparent or opaque), 4 is the cover layer of the high temperature electric heater (it can be transparent or opaque) . Among them, the internal electrode spacing is 6mm, the length is 108mm, and the width is 1mm, a total of 15, the width of the bus bar is 8mm, and the thickness of the copper foil is 25μm;

4. Bake the printed electrode pattern in an oven to cure the peelable glue. The baking temperature is 135°C for 40 minutes;

5. The baked sample is etched in 30% FeCl ₃ etching solution. After the etching is completed, it is washed with water and dried, and the peelable glue on the electrode surface is peeled off;

6. Use laser cutting equipment to open a square hole on the polyimide film with silica gel. The size of the hole is 5mm×5mm. The position of the hole should ensure that the end of the bus bar is exposed after the polyimide film is bonded to the electrode pattern. 5mm×5mm electrodes;

8. After aligning the position, attach the polyimide film to the electrode pattern;

9. Make lead wires from the electrodes exposed in the small holes.

The structure of the final high-temperature electric heating sheet is: the heating layer (doped graphene) 1 and the electrode (copper foil) 2 are closely bonded, the inner electrode spacing is 6mm, the length is 108mm, and the width is 1mm. There are 15 bars in total, and the width of the bus bar is 8mm. , copper foil thickness 25μm. The base material 3 and the covering layer 4 sandwich the transparent conductive layer and the electrodes, and play the role of support, fixation and protection. The substrate 3 is a polyimide film with a thickness of 125 μm, and the cover layer 4 is also a polyimide film with a thickness of 125 μm.

The measured resistance of the high-temperature electric heater is 2.7Ω. Connect the lead wires to the positive and negative electrodes of the 7.4V lithium-ion battery respectively. After testing, it can reach a stable state in 5 minutes. At this time, the average temperature of the electric heating film can reach about 176°C (room temperature is 22°C), the temperature distribution image tested with the infrared thermal imaging camera is shown in Figure 23, the temperature uniformity in the effective heating area is ±8K, which conforms to the formula (6), where K=126.5.

After testing, the difference between the highest voltage and the lowest voltage at different positions of the bus bar is 0.2%, and the maximum voltage difference on the inner electrode does not exceed 0.004%.

Example 16:

1. Coating carbon nanotubes on a ceramic material with an area of 140mm×140mm and a thickness of 4mm, the square resistance is about 200Ω/□;

2. Use screen printing equipment to print silver paste electrode patterns on the transferred carbon nanotubes. The pattern shape is shown in Figure 1. It is designed for parallel electrodes. The width of the two parallel electrodes is 8mm, the distance is 12cm, and the thickness of the silver paste is 25μm;

3. Bake the printed electrode pattern in an IR furnace at a temperature of 150°C for 10 minutes, and then sinter in a tunnel furnace at 550°C for 10 minutes;

4. Apply a layer of glass glaze on the glass sheet;

5. Sinter the glass glaze (thickness 115 μm) in the tunnel.

The structure of the obtained high-temperature electric heater is basically the same as in Example 14, except that the heating layer 1 is a carbon nanotube, the width of the two parallel electrodes is 8 mm, the distance is 12 cm, and the thickness of the silver paste is 25 μm. The substrate 3 is a ceramic material with a thickness of 4 mm, and the covering layer 4 is a glass glaze with a thickness of 1 μm.

The measured resistance of the high-temperature electric heater is 200Ω, the lead wires are connected to a DC or AC power supply, and the voltage is adjusted to 220V. After about 15 minutes, the temperature rises to about 300°C (room temperature 22°C) and remains stable. The temperature distribution measured by the infrared thermal imager The image is shown in Figure 24, the temperature uniformity in the effective heating area is ±6K, which conforms to formula (7), where K=165.5.

Example 17:

1. Lay the copper foil with grown graphene (graphene is doped, the square resistance is 125Ω/□) and borosilicate glass with a size of 150mm×150mm and a thickness of 125μm through UV glue, and the size of the copper foil is 130mm ×130mm, thickness 25μm;

2. Curing the UV glue, the wavelength is 365nm, the energy is 1000mJ/cm ²

3. Use screen printing equipment to print a peelable mask on the bonded copper foil. The pattern shape is shown in Figure 4. 1 is the heating layer of the high-temperature electric heater, 2 is the electrode, 21 is the bus bar, 22 is the Internal electrode, 3 is the base material (can be transparent, also can be opaque), 4 is the covering layer of high-temperature electric heater (can be transparent, also can be opaque). Among them, the outer diameter of the bus bar is 96mm, the longest inner electrode is 73mm, and the distance between the inner electrodes is 6mm. A total of 17 intervals are generated, with a width of 1mm and a bus bar width of 8mm. On the bus bar, the first inner electrode goes to the last. The length of the root internal electrode stop is 130mm, and the thickness of the silver paste is 25μm;

4. Bake the printed electrode pattern in an oven to cure the peelable glue. The baking temperature is 135°C for 40 minutes;

5. The baked sample is etched in 30% FeCl ₃ etching solution. After the etching is completed, it is washed with water and dried, and the peelable glue on the electrode surface is peeled off;

6. Use laser cutting equipment to open a square hole on the polyimide film with silica gel. The size of the hole is 5mm×5mm. The position of the hole should ensure that the end of the bus bar is exposed after the polyimide film is bonded to the electrode pattern. 5mm×5mm electrodes;

8. After aligning the position, attach the polyimide film to the electrode pattern;

9. Make lead wires from the electrodes exposed in the small holes.

The structure of the obtained high-temperature electric heater is basically the same as in Example 15, except that the pattern shape is as shown in Figure 4, the electrodes are surrounded by a circle, the outer diameter of the bus bar is 96mm, the longest internal electrode is 73mm, and the distance between the internal electrodes is 6mm , A total of 17 intervals are produced, with a width of 1 mm, a bus bar width of 8 mm, a length of 130 mm from the first internal electrode to the last internal electrode on the bus bar, and a silver paste thickness of 25 μm. The substrate 3 is borosilicate glass with a thickness of 125 μm, and the cover layer 4 is a polyimide film of 4 mm.

The measured resistance of the high-temperature electric heater is 5.3Ω. Connect the lead wires to the positive and negative electrodes of the 7.4V lithium-ion battery respectively. After testing, it can reach a stable state in 5 minutes. At this time, the average temperature of the electric heating film can reach about 180°C (room temperature is 22°C), the temperature distribution image tested with the infrared thermal imaging camera is shown in Figure 25, the temperature uniformity in the effective heating area is ±8K, which conforms to the formula (6), where K=129.8.

After testing, the difference between the highest voltage and the lowest voltage at different positions of the bus bar is 0.3%, and the maximum voltage difference on the inner electrode does not exceed 0.004%.

Example 18:

It is basically the same as Example 14, except that the width of the parallel electrodes is 7 mm, and the spacing is 9 cm; the thickness of the substrate (borosilicate glass) is 3 mm; the thickness of the covering layer (glass glaze) is 75 μm.

The measured resistance of the high-temperature electric heater is 220Ω. The lead wires are connected to a DC or AC power supply, and the voltage is adjusted to 220V. After about 10 minutes, the temperature rises to 269°C (room temperature 22°C) and remains stable, which conforms to the formula (7). Among them, K The value is 103.5, and the temperature distribution image tested with the infrared camera is shown in Figure 26, and the temperature uniformity in the effective heating area is ±9K.

Example 19:

It is basically the same as Example 14, except that graphene is doped, and the number of layers of graphene transferred is one layer as a heating layer, and the measured square resistance is 150Ω/□; the substrate (glass ceramics) The thickness is 300 μm; the thickness of the cover layer (glass glaze) is 75 μm.

The measured resistance of the high-temperature electric heater is 150Ω. The lead wires are connected to a DC or AC power supply, and the voltage is adjusted to 220V. After about 10 minutes, the temperature rises to about 411°C (room temperature 22°C) and remains stable, which conforms to the formula (7). Among them, K The value is 120.5, and the temperature distribution image tested by the infrared thermal imaging camera is shown in Figure 27, and the temperature uniformity in the effective heating area is ±7K.

Example 20:

It is basically the same as Example 14, except that the width of the parallel electrodes is 8mm, and the spacing is 9cm; the thickness of the substrate (quartz glass) is 1mm; the thickness of the covering layer (glass glaze) is 123μm.

The measured resistance of the high-temperature electric heater is 300Ω. The lead wires are connected to a DC or AC power supply, and the voltage is adjusted to 220V. After about 15 minutes, the temperature rises to about 292°C (room temperature 22°C) and remains stable, which conforms to the formula (7). Among them, K The value is 113.1, and the temperature distribution image tested by the infrared thermal imaging camera is shown in Figure 28, and the temperature uniformity in the effective heating area is ±4K.

Example 21:

Substantially the same as Example 14, the difference is: transfer doped graphene monolayer as the heating layer, the measured square resistance is 150Ω/□, the parallel electrode width is 10mm, and the spacing is 13cm; The thickness is 1 mm; the thickness of the cover layer (glass glaze) is 123 μm.

The measured resistance of the high-temperature electric heater is 390Ω, the lead wires are connected to a DC or AC power supply, and the voltage is adjusted to 220V. After about 15 minutes, the temperature rises to about 323°C (room temperature 22°C) and remains stable, which conforms to the formula (7). Among them, K The value is 157.7, and the temperature distribution image tested by the infrared camera is shown in Figure 29, and the temperature uniformity in the effective heating area is ±7K.

Example 22:

Substantially the same as Example 14, the difference is: transfer doped graphene five layers as the heating layer, the measured square resistance is 316Ω/□, the parallel electrode width is 8mm, and the spacing is 7cm; the thickness of the substrate (sapphire) is 50 μm; the thickness of the cover layer (polyimide film) was 100 μm.

The measured resistance of the high-temperature electric heater is 330Ω, the lead wires are connected to a DC or AC power supply, and the voltage is adjusted to 220V. After about 15 minutes, the temperature rises to about 470°C (room temperature 22°C) and remains stable, which conforms to formula (7), where K The value is 143.2, and the temperature distribution image tested by the infrared camera is shown in Figure 30, and the temperature uniformity in the effective heating area is ±5K.

In Examples 14-22, the UV glue can also be replaced by high-temperature-resistant glue such as various UV light-curing and heat-curing resins, organic silica gel, polyimide glue, and silicate inorganic adhesive.

In embodiments 14-22, there are many choices as the substrate, such as glass-ceramics, quartz glass, borosilicate glass, sapphire and various ceramic materials, etc., which have good thermal conductivity and high temperature resistance materials that those skilled in the art can think of .

The above description is only a preferred embodiment of the utility model, and is not intended to limit the utility model. Although the utility model has been described in detail with reference to the aforementioned embodiments, for those skilled in the art, it can still understand the aforementioned The technical solutions described in each embodiment are modified, or some of the technical features are equivalently replaced. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present utility model shall be included in the protection scope of the present utility model.

Claims (37)

1. a low-voltage transparent electric heating film, including transparent base, transparency conducting layer, electrode；Transparency conducting layer is formed at least side of transparent base；It is characterized in that: electrode is made up of busbar and some interior electrodes, and interior electrode is extended towards by busbar and forms interdigital electrode；Electrode is positioned on transparency conducting layer and makes electrical contact with transparency conducting layer.

A kind of low-voltage transparent electric heating film the most according to claim 1, it is characterized in that: electrode is made up of thick busbar and some thin interior electrodes, busbar connects the negative or positive electrode of power supply, making two adjacent interior polarities of electrode contrary, in the electric current that during energising, positive bus bar provides is flowed into corresponding negative pole by electrode in each positive pole, electrode the most all imports negative bus bar.

Low-voltage transparent electric heating film the most according to claim 1 and 2, it is characterised in that: the negative or positive electrode of busbar one termination power.

A kind of low-voltage transparent electric heating film the most according to claim 1 and 2, it is characterized in that: be respectively provided with positive and negative two set electrodes on transparency conducting layer two sides, interior electrode of this two sets electrode staggers certain distance, the most positive and negative interdigital electrode is respectively placed in transparency conducting layer both sides, forms the interdigital electrode separated by transparency conducting layer.

A kind of low-voltage transparent electric heating film the most according to claim 1 and 2, it is characterised in that: described transparency conducting layer is single or multiple lift Graphene.

A kind of low-voltage transparent electric heating film the most according to claim 1 and 2, it is characterised in that: electrode material is Copper Foil.

A kind of low-voltage transparent electric heating film the most according to claim 5, it is characterised in that: electrode is positioned on graphene layer and is integrally formed with graphene layer.

A kind of low-voltage transparent electric heating film the most according to claim 1 and 2, it is characterised in that: electrode is formed between transparent base and transparency conducting layer.

A kind of low-voltage transparent electric heating film the most according to claim 1 and 2, it is characterised in that: protective mulch on electrode and transparency conducting layer.

A kind of low-voltage transparent electric heating film the most according to claim 1 and 2, it is characterised in that: by connected in series or in parallel for the electrode of the present invention.

11. a kind of low-voltage transparent electric heating films according to claim 1 and 2, it is characterized in that: described interior electrode is linear, waveform or zigzag, the pattern form of described busbar and interior electrode composition is according to the shape of Electric radiant Heating Film and application demand, can linear, shaped form, it is possible to surround circle, ellipse or arbitrary shape.

12. a kind of low-voltage transparent electric heating films according to claim 1 and 2, it is characterised in that: final warming temperature, initial temperature, supply voltage, the square resistance of electrode spacing and transparency conducting layer meets equation below in two:

T=kU²/d²R+t (1)

Wherein:

T initial temperature, unit is DEG C；

T Electric radiant Heating Film institute of heating up is to final warming temperature, and unit is DEG C；

U supply voltage, unit is V, U≤12V；

Electrode spacing in d, unit is cm；

R transparency conducting layer square resistance, unit is Ω/；

K constant, span is that 10-200, k span has different according to the coefficient of conductivity between Electric radiant Heating Film from air, and the coefficient of conductivity between Electric radiant Heating Film and air is inversely proportional to.

13. a kind of low-voltage transparent electric heating films according to claim 1 and 2, it is characterized in that: the setting of busbar should ensure that interior electrode is arranged on the diverse location ceiling voltage of busbar and minimum voltage difference less than 10%, meet equation below (2):

n(n+1)lρ_l/ WHR ＜ 1/5 (2)

Wherein:

N interval is created altogether in electrode makes the area that busbar surrounds in n；

ρ₁Bus bar materials resistivity, unit is Ω m；

Electrode every root length degree in l, is calculated by the longest interior electrode when length does not waits, and unit is m；

W busbar width, unit is m；

H busbar thickness, unit is m；

R transparency conducting layer square resistance, unit is Ω/.

14. a kind of low-voltage transparent electric heating films according to claim 1 and 2, it is characterised in that: on same interior electrode, maximum voltage difference is less than 10%, need to meet equation below (3):

nl²ρ₂/ whLR ＜ 1/5 (3)

Wherein:

In n, electrode creates n interval；

Electrode every root length degree in l, is calculated by the longest interior electrode when length does not waits, and unit is m；

ρ₂Inner electrode resistivity, unit is Ω m；

Electrode width in w, unit is m；

Thickness of electrode in h, unit is m；

In being played last root by first interior electrode on L every busbar, electrode stops the length that common property is raw, and unit is m；

R transparency conducting layer square resistance, unit is Ω/.

15. 1 kinds of high-temperature electric backings, including base material, zone of heating, electrode；Zone of heating is formed at least side of base material；It is characterized in that: described electrode structure is interdigital structure or is two parallel strip structures.

16. high-temperature electric backings according to claim 15, it is characterised in that: by the electrode serial or parallel connection of the present invention.

17. high-temperature electric backings according to claim 15, it is characterised in that: described interdigitated electrode structure is as follows:

It is made up of thick busbar and some thin interior electrodes, busbar connects the negative or positive electrode of power supply, making two adjacent interior polarities of electrode contrary, in the electric current that during energising, positive bus bar provides is flowed into corresponding negative pole by electrode in each positive pole, electrode the most all imports negative bus bar.

18. high-temperature electric backings according to claim 17, it is characterised in that: the negative or positive electrode of busbar one termination power.

19. high-temperature electric backings according to claim 17, it is characterized in that: be respectively provided with positive and negative two set electrodes on zone of heating two sides, interior electrode of this two sets electrode staggers certain distance, and the most positive and negative interdigital electrode is respectively placed in zone of heating both sides, forms the interdigital electrode that heated layer separates.

20. high-temperature electric backings according to claim 17, it is characterised in that: final warming temperature, initial temperature, supply voltage, the square resistance of electrode spacing and zone of heating meets equation below (4) in two:

T=kU²/d²R+t (4)

Wherein:

T initial temperature, unit is DEG C；

T electric heating piece institute of heating up is to final warming temperature, and unit is DEG C；

U supply voltage, unit is V；

Electrode spacing in d, unit is cm；

R zone of heating square resistance, unit is Ω/；

K constant, span is that 10-200, k span has different according to the coefficient of conductivity between electric heating piece from air, and the coefficient of conductivity between electric heating piece and air is inversely proportional to.

21. high-temperature electric backings according to claim 17, it is characterised in that: the setting of busbar should ensure that interior electrode is arranged on the diverse location ceiling voltage of busbar and minimum voltage difference less than 10%, meets equation below (5):

n(n+1)lρ_l/ WHR ＜ 1/5 (5)

Wherein:

N interval is created altogether in electrode makes the area that busbar surrounds in n；

ρ₁Bus bar materials resistivity, unit is Ω m；

Electrode every root length degree in l, is calculated by the longest interior electrode when length does not waits, and unit is m；

W busbar width, unit is m；

H busbar thickness, unit is m；

R zone of heating square resistance, unit is Ω/.

22. high-temperature electric backings according to claim 17, it is characterised in that: on same interior electrode, maximum voltage difference is less than 10%, need to meet equation below (6):

nl²ρ₂/ whLR ＜ 1/5 (6)

Wherein:

In n, electrode creates n interval；

Electrode every root length degree in l, is calculated by the longest interior electrode when length does not waits, and unit is m；

ρ₂Inner electrode resistivity, unit is Ω m；

Electrode width in w, unit is m；

Thickness of electrode in h, unit is m；

In being played last root by first interior electrode on L every busbar, electrode stops the length that common property is raw, and unit is m；

R zone of heating square resistance, unit is Ω/.

23. high-temperature electric backings according to claim 15, it is characterised in that: two strip electrodes of described parallel pole are arranged at two edges of zone of heating.

24. high-temperature electric backings according to claim 23, it is characterised in that: described parallel pole is straight line parallel electrode or oriented parallel electrode or broken line parallel pole.

25. high-temperature electric backings according to claim 23, it is characterised in that: the square resistance of final warming temperature, initial temperature, supply voltage, two electrode spacings and zone of heating meets equation below (7):

T=kU²/d²R+t (7)

Wherein:

T initial temperature, unit is DEG C；

T high-temperature heating sheet institute of heating up is to final warming temperature, and unit is DEG C；

U supply voltage, unit is V；

The spacing of d two parallel pole, unit is cm；

R zone of heating square resistance, unit is Ω/；

K constant, span is that 10-200, k span has different according to the coefficient of conductivity between electric heating piece from air, and the coefficient of conductivity between electric heating piece and air is inversely proportional to.

26. according to the high-temperature electric backing described in any one of claim 23-25, it is characterised in that: the width of described parallel pole is 7-10mm.

27. high-temperature electric backings according to claim 26, it is characterised in that: the width of described parallel pole is 8mm.

28. according to the high-temperature electric backing described in any one of claim 23-25, it is characterised in that: the spacing of described parallel pole is 9-13cm.

29. high-temperature electric backings according to claim 28, it is characterised in that: the spacing of described parallel pole is 10cm.

30. high-temperature electric backings according to claim 15, it is characterised in that: the material of described zone of heating is 3-5 layer graphene.

31. high-temperature electric backings according to claim 15, it is characterised in that: described base material is exotic material, and the thickness of described base material is 20-5000 μm.

32. high-temperature electric backings according to claim 31, it is characterised in that: the thickness of described base material is 50-3000 μm.

33. high-temperature electric backings according to claim 15, it is characterised in that: described electrode material is high temperature resistant conductive silver paste.

34. high-temperature electric backings according to claim 15, it is characterised in that: protective mulch on the electrode of described high-temperature electric backing and zone of heating, with what base material echoed mutually, the zone of heating being provided with electrode is clipped in the middle.

35. high-temperature electric backings according to claim 34, it is characterised in that: the material of described protective layer is exotic material, and the thickness of described cover layer is 1-1000 μm.

36. high-temperature electric backings according to claim 35, it is characterised in that: the thickness of described cover layer is 5-200 μm.

37. high-temperature electric backings according to claim 36, it is characterised in that: the thickness of described protective mulch is 75-123 μm.