CN111770593B

CN111770593B - Heating element, preparation method thereof and heating device

Info

Publication number: CN111770593B
Application number: CN202010452934.4A
Authority: CN
Inventors: 周宏明; 刘华; 肖俊杰
Original assignee: Shenzhen Smoore Technology Ltd
Current assignee: Shenzhen Smoore Technology Ltd
Priority date: 2020-05-26
Filing date: 2020-05-26
Publication date: 2023-01-20
Anticipated expiration: 2040-05-26
Also published as: CN111770593A

Abstract

The invention relates to a heating body, a preparation method thereof and a heating device. This heat-generating body includes the base member, generates heat layer and overburden, and the layer that generates heat is located the base member, and the overburden is located the layer that generates heat, and the overburden is formed by the raw materials sintering of preparation overburden, and the raw materials of preparation overburden include: 0.5 to 55 portions of glass powder, 5 to 75 portions of carbon material and 0 to 35 portions of inorganic filler. The heating element has good adhesion to smoke scale.

Description

Heating element, preparation method thereof and heating device

Technical Field

The invention relates to the technical field of heating elements, in particular to a heating body, a preparation method thereof and a heating device.

Background

The traditional tobacco generates smoke by combustion, and a large amount of harmful substances are volatilized under the condition of high-temperature roasting at the temperature of over 800 ℃. In order to meet the requirement of people on nicotine and reduce the harm caused by the combustion of tobacco, a non-combustible heating aerosol forming device (smoking set) is produced. The heating non-combustion smoking set mainly uses the low temperature of 200-400 ℃ to bake the tobacco to generate smoke, but does not have a large amount of harmful substances caused by cracking.

At present, the heating mode of heating the non-combustion smoking set is mainly central heating or peripheral heating. The central heating has high thermal efficiency, and does not need heat insulation treatment, but the central heating inevitably contacts the heating body with the tobacco. Therefore, when the smoking set is heated in a central heating mode and does not burn, liquid substances which cannot be vaporized are separated out while tobacco is carbonized, smoke scale is inevitably formed, the smoke scale is easily adhered to the surface of the heating element and is difficult to clean, and the smoking taste is easily deteriorated after the smoking set is used for a period of time when the smoking set is heated in the central heating mode and does not burn.

Disclosure of Invention

In view of this, it is necessary to provide a heat-generating body which is resistant to adhesion of soot.

A heating body comprises a base body, a heating layer and a covering layer, wherein the heating layer is located on the base body, the covering layer is located on the heating layer, the covering layer is formed by sintering raw materials for preparing the covering layer, and the raw materials for preparing the covering layer comprise: 0.5 to 55 portions of glass powder, 5 to 75 portions of carbon material and 0 to 35 portions of inorganic filler.

The covering layer of the heating body is formed by sintering 0.5-55 parts of glass powder, 5-75 parts of carbon material and 0-35 parts of inorganic filler, and the shrinkage of the glass powder and the carbon material is inconsistent during sintering, so that the surface of the obtained covering layer is uneven, the bonding area of the covering layer and the soot is reduced, and the bonding speed of the soot is reduced; the carbon material has lower surface energy after being sintered, reduces the surface wettability of the tobacco tar to the heating element, ensures that the tobacco tar is not easy to spread on the surface of the covering layer, and effectively reduces the formation of smoke scale; in addition, the carbon material in the covering layer has loose structure after sintering, and even if the soot is adhered, the soot is easy to wipe off due to small adhesion force with the soot.

In one embodiment, the covering layer is formed by pulping raw materials for preparing the covering layer, forming, drying at 100-300 ℃, and sintering at 600-1000 ℃.

In one embodiment, the glass powder comprises the following components in percentage by mass: 10 to 60 percent of silicon oxide, 10 to 40 percent of boron oxide, 0.5 to 5 percent of aluminum oxide, 0 to 8 percent of calcium oxide, 2 to 15 percent of zinc oxide, 0 to 6 percent of magnesium oxide, 1 to 5 percent of titanium oxide, 5 to 15 percent of sodium oxide, 0 to 3 percent of potassium oxide and 0.2 to 4 percent of zirconium oxide.

In one embodiment, the carbon material is selected from at least one of graphite, carbon fiber, mesocarbon microbeads, glassy carbon, carbon-carbon composites, hard carbon, porous activated carbon, carbon black, diamond, carbon nanotubes, fullerenes, and graphene.

In one embodiment, the inorganic filler is selected from at least one of silica, alumina, zirconia, zinc oxide, calcium oxide, and titanium oxide.

In one embodiment, the glass powder comprises the following components in percentage by mass: 30 to 50 percent of silicon oxide, 15 to 35 percent of boron oxide, 2 to 3 percent of aluminum oxide, 3 to 8 percent of calcium oxide, 2 to 10 percent of zinc oxide, 2 to 4 percent of magnesium oxide, 3 to 5 percent of titanium oxide, 10 to 15 percent of sodium oxide, 1 to 2 percent of potassium oxide and 1 to 2 percent of zirconium oxide; and/or the presence of a catalyst in the reaction mixture,

the carbon material is at least one selected from graphite, carbon fiber, mesocarbon microbeads, glassy carbon, carbon-carbon composite materials, hard carbon, porous activated carbon, carbon black, diamond, carbon nanotubes, fullerene and graphene; and/or the presence of a catalyst in the reaction mixture,

the inorganic filler is at least one selected from the group consisting of silica, alumina, zirconia, zinc oxide, calcium oxide, and titanium oxide.

In one embodiment, the raw material for preparing the covering layer further comprises 10 to 60 parts of organic vehicle.

In one embodiment, the organic vehicle comprises, in mass percent: 2 to 10 percent of ethyl cellulose, 1 to 8 percent of acrylic resin, 3 to 12 percent of tributyl citrate, 25 to 65 percent of terpineol, 8 to 22 percent of butyl carbitol, 5 to 30 percent of butyl carbitol acetate and 0.5 to 4 percent of dispersant.

In one embodiment, the raw materials for preparing the cover layer include: 5 to 55 parts of glass powder, 5 to 75 parts of carbon material, 0 to 25 parts of inorganic filler and 20 to 45 parts of organic carrier.

In one embodiment, the thickness of the cover layer is 5 μm to 500 μm.

A method for preparing a heating element comprises the following steps:

and preparing the raw materials of the covering layer prepared in the heating element into slurry, placing the slurry on a base body with a heating layer, and sintering to form the heating element.

A heating device comprises the heating element or the heating element prepared by the preparation method of the heating element and a base, wherein the heating element is arranged on the base.

Drawings

FIG. 1 is a schematic view of a heat generating body of an embodiment;

FIG. 2 is a schematic view of a heat generating body according to another embodiment.

Detailed Description

To facilitate an understanding of the invention, the invention will now be described more fully hereinafter with reference to the accompanying drawings. Some embodiments of the invention are shown in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may be present. When the terms "vertical," "horizontal," "left," "right," "upper," "lower," "inner," "outer," "bottom," and the like are used to indicate an orientation or positional relationship, it is for convenience of description only based on the orientation or positional relationship shown in the drawings, and it is not intended to indicate or imply that the device or element so referred to must have a particular orientation, be constructed in a particular orientation, and be operated in a particular orientation, and therefore, is not to be construed as limiting the application. Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

Referring to fig. 1, according to an embodiment of the present invention, a heating apparatus is provided, which includes a heating unit 10 and a base, and the heating unit 10 is mounted on the base. In an alternative specific example, the heating device is a heating non-burning smoking set. At this time, the heating body 10 is used to heat the tobacco so that the tobacco releases smoke.

The heat generating body 10 includes a base 110, a heat generating layer 120, and a covering layer 130. The heat generating layer 120 is located on the base 110, and the cover layer 130 is located on a side of the heat generating layer 120 away from the base 110. That is, the heat generating layer 120 and the cover layer 130 are sequentially laminated on the base 110. In the present embodiment, the heat generating layer 120 and the cover layer 130 are sequentially laminated on one side of the base 110.

In particular, the substrate 110 serves as a support for carrying other film layers thereon. In the present embodiment, the substrate 110 is a ceramic substrate 110. Further, the substrate 110 is a zirconia ceramic substrate 110 or an alumina ceramic substrate 110. In an alternative specific example, the substrate 110 is a zirconia ceramic substrate. The zirconia ceramics have high strength and hardness, high temperature resistance and high chemical stability. The heat generating element 10 is hard to chemically react with the substance stacked on the base 110 even under high temperature conditions, and has high hardness and a good heat generating effect.

It is understood that in other embodiments, the substrate 110 is not limited to a ceramic substrate, but may be other substrates 110 commonly used in the art, such as a stainless steel substrate, a glass substrate, or a nickel-cobalt alloy substrate. The stainless steel substrate has good bending resistance, is not easy to break and has good heat conduction effect. The nickel-cobalt alloy matrix has strong high-temperature oxidation resistance.

In the present embodiment, the thickness of the substrate 110 is 0.1mm to 3.0mm. Of course, in other embodiments, the thickness of the substrate 110 is not limited to the above, and may be adjusted according to actual requirements.

The substrate 110 is shaped like a sheet, a strip, a tube, a pot, a column or a cone. In an alternative embodiment, the base 110 includes a body and a tip connected to the body, the tip having a width that gradually decreases from an end proximate to the body to an end distal from the body to facilitate tobacco insertion. It is understood that in other embodiments, the shape of the substrate 110 is not limited to the above, and may be other shapes.

The heat generating layer 120 is for generating heat. In the present embodiment, the heating method of the heat generating layer 120 is resistance heating. Specifically, the heat generating layer 120 includes a heat generating line and a conductive line electrically connected to the heat generating line. The heating circuit is used for heating, and the conductive circuit is used for electrically connecting the power supply and the heating circuit. The conducting circuit is made of a metal simple substance. The heating circuit is made of a material which has small resistivity and stable structural performance after high-temperature heating. Specifically, the material of the heating circuit is a metal simple substance or an alloy. Further, the material of the conductive line is selected from one of copper, silver and aluminum. The material of the heating circuit is selected from one of silver, silver-palladium alloy, platinum, nickel and tungsten.

It is understood that in other embodiments, the material of the conductive line and the material of the heating line are not limited to the above, and may be other materials commonly used in the art. Of course, in other embodiments, the heating method of the heat generating layer 120 is not limited to the above resistance heating, and other heating methods commonly used in the art, such as electromagnetic induction heating, may also be used.

The shape of the heat generating layer 120 is not limited, and may be circular, polygonal, elliptical, or fan-shaped.

In the present embodiment, the thickness of the heat generating layer 120 is 3 μm to 100 μm. Further, the thickness of the heat generating layer 120 is 10 μm to 70 μm. Of course, in other embodiments, the thickness of the heat generating layer 120 is not limited to the above, and may be adjusted according to actual requirements.

The cover layer 130 serves to insulate and conduct heat, while also protecting the heat generating layer 120. In the present embodiment, the cover layer 130 is formed by sintering the raw material for forming the cover layer 130 at 600 to 1000 ℃. Specifically, the raw materials for preparing the cover layer 130 include: 0.5 to 55 portions of glass powder, 5 to 75 portions of carbon material and 0 to 35 portions of inorganic filler.

In an alternative specific example, the glass frit is 5 parts, 10 parts, 15 parts, 20 parts, 23 parts, 35 parts, 45 parts, 50 parts, or 55 parts by mass. Furthermore, the glass powder is 5-55 parts by mass. Furthermore, the mass portion of the glass powder is 15 to 45 portions.

In an optional specific example, the glass frit comprises, by mass percent: 10 to 60 percent of silicon oxide, 10 to 40 percent of boron oxide, 0.5 to 5 percent of aluminum oxide, 0 to 8 percent of calcium oxide, 2 to 15 percent of zinc oxide, 0 to 6 percent of magnesium oxide, 1 to 5 percent of titanium oxide, 5 to 15 percent of sodium oxide, 0 to 3 percent of potassium oxide and 0.2 to 4 percent of zirconium oxide. Further, the glass powder comprises the following components in percentage by mass: 20 to 50 percent of silicon oxide, 10 to 35 percent of boron oxide, 1 to 4 percent of aluminum oxide, 2 to 8 percent of calcium oxide, 2 to 12 percent of zinc oxide, 2 to 5 percent of magnesium oxide, 2 to 5 percent of titanium oxide, 8 to 15 percent of sodium oxide, 1 to 3 percent of potassium oxide and 1 to 3 percent of zirconium oxide. Furthermore, the glass powder comprises the following components in percentage by mass: 30 to 50 percent of silicon oxide, 15 to 35 percent of boron oxide, 2 to 3 percent of aluminum oxide, 3 to 8 percent of calcium oxide, 2 to 10 percent of zinc oxide, 2 to 4 percent of magnesium oxide, 3 to 5 percent of titanium oxide, 10 to 15 percent of sodium oxide, 1 to 2 percent of potassium oxide and 1 to 2 percent of zirconium oxide.

The carbon material has lower surface energy, reduces the wettability of the soot on the surface of the heating element 10, makes the soot not easy to spread on the surface of the heating element 10, and can effectively reduce the adhesion of the soot. Specifically, the carbon material and the glass powder are not shrunk uniformly during sintering, the surface of the obtained covering layer 130 is uneven, so that the bonding area with the soot is reduced, the carbon material has a loose structure and small bonding force with the soot, and the soot is easy to wipe off even if the soot is bonded.

In an alternative specific example, the mass part of the carbon material is 5 parts, 8 parts, 10 parts, 15 parts, 20 parts, 33 parts, 40 parts, 48 parts, 50 parts, 55 parts, 60 parts, or 75 parts. Further, the carbon material is 5 to 55 parts by mass. Further, the carbon material is 10 to 55 parts by mass.

In an alternative specific example, the carbon material is selected from at least one of graphite, carbon fiber, mesocarbon microbeads, glassy carbon, carbon-carbon composites, hard carbon, porous activated carbon, carbon black, diamond, carbon nanotubes, fullerenes, and graphene. The carbon material is selected from one of graphite, carbon fiber, mesocarbon microbeads, glassy carbon, carbon-carbon composite materials, hard carbon, porous activated carbon, carbon black, diamond, carbon nanotubes, fullerene and graphene. The carbon material is selected from one of graphite, diamond and carbon black.

In an alternative specific example, the inorganic filler is present in an amount of 0 parts, 2 parts, 5 parts, 7 parts, 10 parts, 13 parts, 17 parts, 21 parts, 25 parts, 28 parts, 30 parts, or 35 parts by mass. Further, the inorganic filler is 0 to 30 parts by mass. Furthermore, the inorganic filler is 0 to 25 parts by mass.

In an alternative specific example, the inorganic filler is selected from at least one of silica, alumina, zirconia, zinc oxide, calcium oxide, and titanium oxide. Further, the inorganic filler is one selected from the group consisting of silica, alumina, zirconia, zinc oxide, calcium oxide, and titanium oxide. Further, the inorganic filler is selected from one of alumina and zirconia.

In an alternative embodiment, the raw materials for preparing the cover layer 130 include: 5 to 55 parts of glass powder, 5 to 75 parts of carbon material and 0 to 25 parts of inorganic filler.

In an alternative embodiment, the raw materials for preparing the cover layer 130 include: 15 to 45 portions of glass powder, 10 to 55 portions of carbon material and 0 to 25 portions of inorganic filler.

In other embodiments, the material used to form the capping layer 130 further comprises an organic vehicle. The organic carrier is a liquid fluid, and functions to prepare solid powders such as glass powder, carbon material, organic filler and the like into flowable slurry for construction on the heating element 10. Of course, the organic vehicle will ablate during sintering.

In an alternative specific example, the organic vehicle is present in an amount of 10 to 60 parts by mass. Specifically, the organic vehicle is 10 parts, 12 parts, 18 parts, 20 parts, 30 parts, 40 parts, 45 parts, 50 parts, 54 parts or 60 parts by mass. Further, the mass portion of the organic carrier is 5-55 portions. Further, the mass portion of the organic carrier is 20-45 portions.

In an alternative specific example, the organic vehicle comprises, in mass percent: 2 to 10 percent of ethyl cellulose, 1 to 8 percent of acrylic resin, 3 to 12 percent of tributyl citrate, 25 to 65 percent of terpineol, 8 to 22 percent of butyl carbitol, 5 to 30 percent of butyl carbitol acetate and 0.5 to 4 percent of dispersant. Further, the organic carrier comprises the following components in percentage by mass: 3 to 8 percent of ethyl cellulose, 2 to 4 percent of acrylic resin, 6 to 10 percent of tributyl citrate, 45 to 55 percent of terpineol, 14 to 18 percent of butyl carbitol, 12 to 23 percent of butyl carbitol acetate and 1 to 3 percent of dispersant. The dispersant is not limited and is a dispersant commonly used in the art.

In an alternative embodiment, the raw materials for preparing the cover layer 130 include: 5 to 55 parts of glass powder, 5 to 75 parts of carbon material, 0 to 25 parts of inorganic filler and 20 to 45 parts of organic carrier.

In an alternative embodiment, the raw materials for preparing the cover layer 130 include: 15 to 45 portions of glass powder, 10 to 55 portions of carbon material, 0 to 25 portions of inorganic filler and 25 to 45 portions of organic carrier.

In an alternative embodiment, the sintering temperature for forming the cap layer 130 is 600 ℃, 620 ℃, 650 ℃, 700 ℃, 710 ℃, 750 ℃, 780 ℃, 800 ℃, 830 ℃, 850 ℃, 900 ℃, 930 ℃, 950 ℃ or 1000 ℃. Further, the sintering temperature for preparing the capping layer 130 is 710 to 900 ℃. Further, the sintering temperature for preparing the capping layer 130 is 710 to 850 ℃. When the sintering temperature for preparing the covering layer 130 is 600-1000 ℃, the glass powder is melted and the carbon material and the inorganic filler are bonded together to form a film layer, and the film layer has higher hardness, better temperature resistance and higher reliability. When the sintering temperature is lower than 600 ℃, the covering layer is not compact in sintering and poor in hardness; at sintering temperatures above 1000 c, the carbon material in the cover layer is easily oxidized, resulting in a higher surface energy.

The base is used to support the heating element 10. In the present embodiment, the heating element 10 is detachably connected to the base. Of course, in other embodiments, the heating element 10 may be fixed to the base.

In the present embodiment, the heating apparatus further includes a power supply for supplying power to the heating element 10. Specifically, the power source is located within the base. Of course, in other embodiments, the power source may be located outside the base. For example, disposed proximate to the base.

Of course, in other embodiments, the heat-generating body may further include a transition layer. Specifically, the transition layer is located between base member and the layer that generates heat for increase the cohesion of the layer that generates heat and base member.

Of course, in other embodiments, the heat-generating body may further include a dielectric layer. Specifically, the dielectric layer is located between the heating layer and the covering layer and used for increasing the binding force between the heating layer and the covering layer. In this case, if the dielectric layer has an insulating function, the cover layer does not have to have an insulating function.

Of course, in other embodiments, the heat generating layer and the cover layer may be sequentially laminated on opposite sides of the base, such as the embodiment shown in fig. 2. In the embodiment shown in fig. 2, the heat generating body 20 includes two heat generating layers 220 and two cover layers 230. Two heat generating layers 220 are respectively positioned on two opposite surfaces of the base body 210, one cover layer 230 is positioned on one heat generating layer 220, and the other cover layer 230 is positioned on the other heat generating layer 220.

Of course, in other embodiments, the heat generating body may further include two cover layers and one heat generating layer. In an optional specific example, the base body is in a sheet shape, one covering layer is positioned on one side of the heat generating layer far away from the base body, and the other covering layer is positioned on one side of the base body far away from the heat generating layer.

The heating device at least has the following advantages:

(1) The heating device comprises the heating body, the preparation raw materials of the covering layer of the heating body comprise glass powder and a carbon material, and the shrinkage of the glass powder and the carbon material is inconsistent during sintering so that the surface of the covering layer is uneven, thereby reducing the bonding area of the covering layer and the smoke scale and reducing the bonding speed of the smoke scale; the carbon material has lower surface energy after being sintered, so that the surface wettability of the tobacco tar to the heating body is reduced, the tobacco tar is not easy to spread on the surface of the covering layer, and the formation of smoke scale is effectively reduced; in addition, because the carbon material in the covering layer has loose structure after being sintered, the carbon material has small bonding force with the smoke scale, and the smoke scale is easy to wipe off even if the smoke scale is bonded. Therefore, the heating device is not easy to damage and has longer service life.

(2) When the heating device is used, the taste consistency is good: after a heating body of a traditional heating device is used for a long time, the temperature field of the heating body is damaged due to the fact that a large amount of soot is bonded on the surface of the heating body, and then the temperature is influenced to be transferred to tobacco shreds, and finally the taste of the tobacco shreds is reduced. The heating body of the heating device has good capability of resisting smoke scale, and reduces the adhesion of the smoke scale, thereby reducing the influence of the smoke scale on the temperature field of the heating body and ensuring that the heating device has good taste consistency.

(3) The heating body of the heating device is more beautiful: because the heating element is not easy to stick smoke and scale, the use process is cleaner.

(4) When the heating device is used, the cigarette can be plugged and pulled more smoothly: the heating body surface of the heating device is not easy to stick cigarette scale, the cross section of the heating body can not be obviously increased, the resistance of a cigarette in the process of inserting the cigarette can not be obviously increased, and the cigarette can be inserted and pulled more smoothly.

An embodiment of the present invention also provides a method for producing the above heating element, including the steps of:

and step S110, providing a base body with a heat-generating layer.

Specifically, the material of the base and the material of the heat generating layer (including the material of the heat generating circuit and the material of the conductive circuit) are as described above, and will not be described herein again. The method for preparing the base body having the heat generating layer may be prepared by a method common in the art, for example, a method in which a slurry made of raw materials for preparing the heat generating circuit and a slurry made of raw materials for preparing the conductive circuit are printed on the base body to a certain thickness, respectively, and then sintered to prepare the base body having the heat generating layer. Of course, the thickness of the heat generating layer produced depends on the thickness of the printed paste. Furthermore, the sintering temperature for preparing the heating layer is 700-900 ℃. Furthermore, the sintering temperature of the heating layer is 800-900 ℃.

Step S130, preparing a covering layer on the heating layer.

Specifically, slurry made of raw materials for preparing the covering layer is placed on a base body with the heating layer and then sintered to prepare the covering layer. Wherein the sintering temperature is 600-1000 ℃. The materials and temperatures for the preparation of the cover layer are as described above and will not be described in detail here.

Of course, before sintering, the step of drying the substrate carrying the slurry is also included. In an optional specific example, the temperature for drying is 100 ℃ to 300 ℃. Further, the drying temperature is 100-200 ℃.

In the present embodiment, the step of preparing the slurry for the cover layer includes: uniformly mixing the raw materials for preparing the covering layer, then rolling the mixture for 3 to 5 times by using a three-high mill, and further dispersing the raw materials for preparing the covering layer to prepare slurry for the covering layer, wherein the particle size of particles in the slurry is less than 25 mu m. The particle size of the particles in the slurry is less than 25 mu m, which shows that the raw materials are fully and uniformly mixed, and the agglomeration phenomenon does not exist, thus meeting the process requirement of later-stage screen printing.

In the present embodiment, a paste made of the raw material of the cover layer is placed on the heat generating layer by means of screen printing. Of course, in other embodiments, the manner of placing the paste made of the raw material for preparing the cover layer on the base having the heat generating layer is not limited to the screen printing, but may be other manners commonly used in the art. Such as dip coating, spray coating, etc.

The preparation method of the heating element prepares the composite layer by sintering at 600-1000 ℃, and under the condition of 600-1000 ℃, the glass powder is melted and the carbon material and the inorganic filler are bonded together to form a film layer, and the film layer has higher hardness, better temperature resistance and higher reliability; outside the temperature range, the film has poor hardness and high surface energy. In addition, the preparation method of the heating element is simple and convenient, and is suitable for industrial production.

DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION

The following detailed description is given with reference to specific examples. The following examples are not specifically described, and other components except inevitable impurities are not included. The examples, which are not specifically illustrated, employ drugs and equipment, all of which are conventional in the art. The experimental procedures without specifying the specific conditions in the examples were carried out under the conventional conditions such as those described in the literature, in books, or as recommended by the manufacturer. The parts in each of the examples and comparative examples are parts by mass.

Example 1

The heating element of example 1 was composed of a base, a heating layer and a covering layer, the heating layer was laminated on the base, and the covering layer was laminated on the heating layer. The base body is made of 430 stainless steel, is sheet-shaped and has the thickness of 0.5mm; the heating layer is made of a silver-palladium thick film coating, and the thickness of the heating layer is 15 mu m; the thickness of the cover layer was 30 μm. The heat-generating body of example 1 was prepared by the following procedure:

(1) The raw materials for preparing the covering layer are stirred and mixed evenly, and then are rolled for 5 times by a three-roll mill, and further dispersed to ensure that the fineness (the particle size of particles in the mixture) is less than 25 mu m, thus preparing the slurry. The raw materials for preparing the covering layer comprise 55 parts of glass powder, 5 parts of graphite, 15 parts of alumina and 25 parts of organic carrier, wherein the glass powder comprises the following components in percentage by mass: 50% silicon oxide, 15% boron oxide, 3% aluminum oxide, 8% calcium oxide, 2% zinc oxide, 2% magnesium oxide, 3% titanium oxide, 10% sodium oxide, 2% potassium oxide, and 1% zirconium oxide; the organic carrier comprises the following components in percentage by mass: 8% of ethyl cellulose, 2% of acrylic resin, 10% of tributyl citrate, 50% of terpineol, 17% of butyl carbitol, 12% of butyl carbitol acetate and 1% of a dispersant.

(2) And (2) forming a coating on the surface with the heating layer by using the slurry prepared in the step (1) in a screen printing mode, drying the coating at 200 ℃, and sintering the dried coating at 750 ℃ to form a compact covering layer, thereby obtaining the heating body in the embodiment 1.

Example 2

The heating element of embodiment 2 is composed of a base body, a heating layer and a covering layer, the heating layer is laminated on the base body, and the covering layer is laminated on the heating layer. The substrate is made of alumina ceramics, is flaky and has the thickness of 1mm; the material of the heating layer is a silver-platinum thick film coating, and the thickness of the heating layer is 25 mu m; the thickness of the cover layer was 60 μm. The heat-generating body of example 2 was prepared by the following steps:

(1) The raw materials for preparing the covering layer are stirred and mixed evenly, and then are rolled for 5 times by a three-roll mill, and further dispersed to ensure that the fineness (the particle size of particles in the mixture) is less than 25 mu m, thus preparing the slurry. The raw materials for preparing the covering layer comprise 30 parts of glass powder, 25 parts of carbon black, 10 parts of zirconia and 35 parts of zirconia, wherein the glass powder comprises the following components in percentage by mass: 40% silica, 20% boria, 3% alumina, 6% calcia, 10% zinc oxide, 4% magnesia, 3% titania, 11% sodium oxide, 1% potassium oxide and 2% zirconia; the organic carrier component is; 6% of ethyl cellulose, 4% of acrylic resin, 8% of tributyl citrate, 55% of terpineol, 14% of butyl carbitol, 12% of butyl carbitol acetate and 2% of a dispersing agent.

(2) And (2) forming a coating on the surface with the heating layer by the slurry prepared in the step (1) in a dip-coating mode, drying the coating at 180 ℃, and sintering the dried coating at 800 ℃ to form a compact covering layer, thereby obtaining the heating element in the embodiment 2.

Example 3

The heating element of example 3 is composed of a base body, a heating layer and a covering layer, the heating layer is laminated on the base body, and the covering layer is laminated on the heating layer. The substrate is made of zirconia ceramic, is flaky and has the thickness of 1.5mm; the material of the heating layer is a tungsten thick film coating, and the thickness of the heating layer is 40 mu m; the thickness of the cover layer was 100. Mu.m. The heat-generating body of example 3 was prepared by the following procedure:

(1) The raw materials for preparing the covering layer are stirred and mixed evenly, rolled for 5 times by a three-high mill, further dispersed to ensure that the fineness (the grain diameter of particles in the mixture) is less than 25 mu m, and prepared into slurry. Wherein, the raw material for preparing the covering layer consists of 5 parts of glass powder, 75 parts of diamond and 20 parts of organic carrier. Wherein the glass powder comprises the following components in percentage by mass: 30% silicon oxide, 30% boron oxide, 2% aluminum oxide, 3% calcium oxide, 8% zinc oxide, 4% magnesium oxide, 5% titanium oxide, 15% sodium oxide, 2% potassium oxide, and 1% zirconium oxide; the organic carrier comprises the following components in percentage by mass: 3% of ethyl cellulose, 2% of acrylic resin, 6% of tributyl citrate, 45% of terpineol, 18% of butyl carbitol, 23% of butyl carbitol acetate and 3% of a dispersant.

(2) And (2) forming a coating on the surface with the heating layer by the slurry prepared in the step (1) in a spraying mode, drying the coating at 120 ℃, and sintering the dried coating at 850 ℃ to form a compact covering layer, thereby obtaining the heating body of the embodiment 3.

Comparative example 1

The heat-generating body of comparative example 1 is substantially the same as the heat-generating body of example 1, except that the raw material of the covering layer of comparative example 1 was prepared: 68 parts of glass powder, 17 parts of alumina and 25 parts of organic carrier, wherein the glass powder comprises the following components in percentage by mass: 50% silicon oxide, 15% boron oxide, 3% aluminum oxide, 8% calcium oxide, 2% zinc oxide, 2% magnesium oxide, 3% titanium oxide, 10% sodium oxide, 2% potassium oxide, and 1% zirconium oxide; the organic carrier comprises the following components in percentage by mass: 8% of ethyl cellulose, 2% of acrylic resin, 10% of tributyl citrate, 50% of terpineol, 17% of butyl carbitol, 12% of butyl carbitol acetate and 1% of dispersing agent.

Comparative example 2

The heat-generating body of comparative example 2 is substantially the same as the heat-generating body of example 1, except that the content of the raw material for preparing the covering layer of comparative example 2 is different from that of example 1, the raw material for preparing the covering layer of comparative example 2 is composed of 60 parts of glass frit, 3 parts of carbon material, 7 parts of inorganic filler and 30 parts of organic vehicle, and the components of the glass frit, the carbon material, the inorganic filler and the organic vehicle are the same as those of example 1.

Comparative example 3

The heat-generating body of comparative example 3 is substantially the same as that of example 1, except that the sintering temperature at the time of preparing the covering layer of comparative example 3 is different from that of example 1, and that of comparative example 3 is 550 ℃.

Comparative example 4

The heat-generating body of comparative example 4 is substantially the same as that of example 1, except that the sintering temperature for preparing the covering layer of comparative example 4 is different from that of example 1, and that for preparing the covering layer of comparative example 4, the sintering temperature is 1050 ℃.

And (3) testing:

the water contact angle and the diiodomethane contact angle of each example and each comparative heating element were measured, and the surface energy of the heating element of each example was calculated; the hardness of the heat-generating bodies of the respective examples and comparative examples was measured, and the results are shown in Table 1.

TABLE 1

As is clear from Table 1 above, the heating elements of examples 1 to 3 had low surface energy and strong resistance to adhesion of soot.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that various changes and modifications can be made by those skilled in the art without departing from the spirit of the invention, and these changes and modifications are all within the scope of the invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A heating body is characterized by comprising a base body, a heating layer and a covering layer, wherein the heating layer is positioned on the base body, the covering layer is positioned on the heating layer, the covering layer is formed by sintering raw materials for preparing the covering layer at 600-1000 ℃, and the raw materials for preparing the covering layer comprise: 0.5 to 55 portions of glass powder, 5 to 75 portions of carbon material and 0 to 35 portions of inorganic filler.

2. A heating body as claimed in claim 1, characterized in that the covering layer is prepared by pulping raw materials for preparing the covering layer, forming, drying at 100-300 ℃, and sintering at 600-1000 ℃.

3. A heating body as set forth in claim 1, characterized in that the glass frit comprises, in mass percent: 10 to 60 percent of silicon oxide, 10 to 40 percent of boron oxide, 0.5 to 5 percent of aluminum oxide, 0 to 8 percent of calcium oxide, 2 to 15 percent of zinc oxide, 0 to 6 percent of magnesium oxide, 1 to 5 percent of titanium oxide, 5 to 15 percent of sodium oxide, 0 to 3 percent of potassium oxide and 0.2 to 4 percent of zirconium oxide.

4. A heat-generating body as described in claim 1, wherein the carbon material is at least one selected from the group consisting of graphite, carbon fiber, mesocarbon microbeads, glassy carbon, a carbon-carbon composite material, hard carbon, porous activated carbon, carbon black, diamond, carbon nanotubes, fullerene, and graphene.

5. A heat-generating body as described in claim 1, characterized in that the inorganic filler is at least one selected from the group consisting of silica, alumina, zirconia, zinc oxide, calcium oxide and titanium oxide.

6. A heat-generating body as described in claim 1, characterized in that the glass frit comprises, in mass percent: 30 to 50 percent of silicon oxide, 15 to 35 percent of boron oxide, 2 to 3 percent of aluminum oxide, 3 to 8 percent of calcium oxide, 2 to 10 percent of zinc oxide, 2 to 4 percent of magnesium oxide, 3 to 5 percent of titanium oxide, 10 to 15 percent of sodium oxide, 1 to 2 percent of potassium oxide and 1 to 2 percent of zirconium oxide; and/or the presence of a catalyst in the reaction mixture,

the carbon material is selected from at least one of graphite, carbon fiber, mesocarbon microbeads, glassy carbon, carbon-carbon composite materials, hard carbon, porous activated carbon, carbon black, diamond, carbon nanotubes, fullerene and graphene; and/or the presence of a catalyst in the reaction mixture,

7. A heat-generating body as described in claim 1, characterized in that a raw material for preparing said covering layer further comprises 10 to 60 parts of an organic vehicle.

8. A heat-generating body as described in claim 7, characterized in that the organic vehicle comprises, in mass percent: 2 to 10 percent of ethyl cellulose, 1 to 8 percent of acrylic resin, 3 to 12 percent of tributyl citrate, 25 to 65 percent of terpineol, 8 to 22 percent of butyl carbitol, 5 to 30 percent of butyl carbitol acetate and 0.5 to 4 percent of dispersant.

9. A heat-generating body as described in any one of claims 1 to 8, characterized in that the raw material for preparing the covering layer comprises: 5 to 55 parts of glass powder, 5 to 75 parts of carbon material, 0 to 25 parts of inorganic filler and 20 to 45 parts of organic carrier.

10. A heat-generating body as described in claim 1, characterized in that the thickness of said covering layer is 5 μm to 500 μm.

11. A method for preparing a heating element is characterized by comprising the following steps:

a heating element as described in any of claims 1 to 9, wherein the raw material for preparing said covering layer is made into a slurry, and is sintered at 600 ℃ to 1000 ℃ after being placed on a base having a heat generating layer, thereby forming a heating element.

12. A heating apparatus comprising the heat-generating body according to any one of claims 1 to 10 or the heat-generating body produced by the method for producing a heat-generating body according to claim 11, and a base, wherein the heat-generating body is mounted on the base.