Multi-sheet-layer porous ceramic matrix and atomization core comprising same

Abstract

Disclosed in the present invention are a multi-sheet-layer porous ceramic matrix and an atomization core comprising same. The multi-sheet-layer porous ceramic matrix is composed of a plurality of groups of ceramic sheet layers which are stacked from top to bottom and sintered into an integral whole. Each group of ceramic sheet layers comprises one to a plurality of ceramic sheet layers. Bubble-shaped micropores are uniformly distributed in each ceramic sheet layer. The average pore diameters of the micropores in different ceramic sheet layers of the same group are the same, and the average pore diameters of the micropores in the ceramic sheet layers of different groups are different. The plurality of groups of ceramic sheet layers are sequentially arranged from bottom to top, and the average pore diameters of the micropores in each group of ceramic sheet layers have the rule of alternating or gradient change in descending order in size; and an electrode layer and a metal heating layer are provided on the atomization surface of the multi-sheet-layer porous ceramic matrix of a multi-sheet-layer porous ceramic atomization core. The beneficial effects of the present invention are as follows: the multi-sheet-layer porous ceramic matrix has a multi-sheet-layer structure and the micropores of each sheet layer form an alternating or gradient pore diameter structure, which has a transition and buffering effect on the transmission of a liquid to be atomized, so that liquid supply and atomization are balanced, and the atomization experience is enhanced.

Description

Multi-layer porous ceramic substrate and atomizing core thereof Technical Field

[0001] The present invention belongs to the technical field of atomizing cores of electronic cigarette atomizers, and in particular relates to a multi-layer porous ceramic substrate and an atomizing core thereof. Background Art

[0002] The atomizing core of the electronic atomizer is used to heat the liquid to be atomized, i.e., the atomizing liquid, and atomize it into an aerosol or vapor, mist or smoke for the user to inhale. The atomizing liquid can be a cigarette liquid or a solution containing medicine for health and medical purposes. The electronic atomizer can be used for electronic cigarettes.

[0003] The atomizer core of current electronic atomizers includes a porous ceramic substrate as a liquid guide, and then a heating element such as a heating wire, heating sheet, or heating film is attached to the liquid guide. When the heating element is energized, it can be used to heat the atomized liquid on the liquid guide and atomize it into an aerosol, vapor, mist, or smoke. Existing porous ceramic substrates used as liquid guides are mainly formed into a ceramic green body in one step and sintered. The micropore structure within the ceramic green body is simple, with similar pore sizes. The liquid guide or liquid supply speed is single, which does not match the requirement of the heating element to consume atomized liquid at different power levels. This leads to an imbalance between liquid supply and atomization, causing the atomizer core of the electronic atomizer to easily suffer from problems such as dry burning and carbon deposition due to insufficient liquid supply during the atomization process, as well as oil explosion and leakage due to excessive liquid supply. Technical issues

[0004] The technical problem solved by the present invention is to overcome the deficiencies of the prior art and provide a multi-layer porous ceramic substrate and an atomizing core thereof. Technical Solutions

[0005] The technical solution of the present invention is a multi-layer porous ceramic matrix, which is composed of several groups of ceramic layers stacked up and down and sintered into one. Each group of ceramic layers includes 1 to several layers of ceramic layers, and each layer of the ceramic layers has bubble-shaped micropores evenly distributed. The average pore size of the micropores in the ceramic layers of different layers in the same group is the same, and the average pore size of the micropores in the ceramic layers of different groups is different. The several groups of ceramic layers are arranged in a bottom-up order, and the average pore size of the micropores in each group of ceramic layers has a pattern of alternating changes in size or gradient changes from large to small.

[0006] Preferably, a group of ceramic green embryos is formed by stacking 1 to several layers of flaky ceramic green embryos, and several groups of the ceramic green embryos are stacked up and down and pressed into one body, and then the binder is removed and sintered. A layer of the ceramic green embryo constitutes a layer of the ceramic sheet after sintering. The ceramic green embryo is made by a tape-casting process using a tape-casting ceramic slurry. The components of the tape-casting ceramic slurry include 40 to 65 parts of ceramic powder, 30 to 50 parts of solvent, 0.1 to 3 parts of slurry dispersant, 1 to 8 parts of plasticizer and 1 to 10 parts of binder, wherein the components of the ceramic powder include 25 to 55 parts of aggregate, 5 to 40 parts of pore-forming agent, 5 to 19 parts of sintering aid and 5 to 35 parts of powder dispersant, wherein the average particle size of the aggregate and pore-forming agent contained in different layers of the same group is the same, and the average particle size of the aggregate and / or pore-forming agent contained in different groups of ceramic green embryos is different.

[0007] Preferably, the average pore diameter of the micropores is 10-50 um, or 15-45 um, or 20-40 um.

[0008] Preferably, the porosity of the micropores is 40%-65%, or 45-60%, or 48-56%.

[0009] Preferably, the thickness of each ceramic layer is 0.1-0.5 mm, or 0.1-0.25 mm, or 0.2-0.4 mm, or 0.25-0.5 mm.

[0010] Preferably, the ceramic sheets have 2 to 10 groups, and each group of the ceramic sheets has 1 to 3 ceramic sheets.

[0011] Preferably, the ceramic sheets include 2 to 5 groups, and each group of the ceramic sheets includes 1 to 2 ceramic sheets.

[0012] Preferably, the ceramic sheets are in 3 or 4 groups, and each group of the ceramic sheets has 1 to 2 ceramic sheets.

[0013] Preferably, the components of the ceramic green body include, by weight, 45 to 55 parts of the ceramic powder, 35 to 45 parts of a solvent, 0.1 to 1 part of a slurry dispersant, 1 to 5 parts of a plasticizer, and 3 to 8 parts of a binder.

[0014] Preferably, the components of the ceramic powder include 35 to 55 parts of the aggregate, 25 to 30 parts of the pore former, 15 to 19 parts of the sintering aid, and 5 to 10 parts of the powder dispersant in parts by weight.

[0015] Preferably, the average particle size of the aggregate is 5-100 um, or 5-50 um, or 10-30 um.

[0016] Preferably, the average particle size of the pore-forming agent is 5 to 100 um, or 15 to 80 um, or 25 to 60 um.

[0017] Preferably, the thickness of each layer of the ceramic green body is 0.1-0.6 mm, or 0.1-0.3 mm, or 0.25-0.45 mm, or 0.3-0.6 mm.

[0018] Preferably, the aggregate is the main material for forming the skeleton of the multi-layer porous ceramic matrix, including at least one of kaolin, diatomaceous earth, alumina, silicon nitride, silicon carbide, quartz sand, glass sand, clay, feldspar powder, fused quartz, cordierite, and mullite.

[0019] Preferably, the pore-forming agent is a material that vaporizes and evaporates during sintering to form micropores in the porous ceramic matrix, including at least one of graphite, starch, wood powder, flour, soybean powder, polystyrene microspheres, polymethyl methacrylate microspheres, sucrose, and fiber.

[0020] Preferably, the sintering aid is a material used to bond aggregates and help sinter at a suitable temperature to form a porous ceramic matrix, including at least one of boron oxide, sodium silicate, silicon oxide, potassium oxide, lithium oxide, barium oxide, magnesium oxide, calcium oxide, iron oxide, titanium oxide, zinc oxide, and zirconium oxide.

[0021] Preferably, the powder dispersant is a material used to promote uniform dispersion of aggregates to prevent precipitation and accumulation, including at least one of paraffin, beeswax, boric acid, oleic acid, stearic acid, polyethylene, polypropylene, polyvinyl acetate, polyvinyl acetal, ethylene-vinyl acetate copolymer resin, vinyl chloride-vinyl acetate copolymer resin, perchlorethylene resin, polyacrylate, and polyamide.

[0022] Preferably, the solvent is a material used to convert ceramic powder into a fluid, including at least one of ethanol, isopropyl alcohol, acetone, butanone, xylene, trichloroethylene, ethyl acetate, and butyl acetate.

[0023] Preferably, the slurry dispersant is a material used to disperse the ceramic powder in the solvent, and includes at least one of oleic acid, boric acid, linseed oil, castor oil, stearic acid, and triolein.

[0024] Preferably, the plasticizer is a material used to improve the plasticity of the ceramic green body, including at least one of polyethylene glycol and dibutyl phthalate.

[0025] Preferably, the binder is a material used to improve the strength of the ceramic green body, including at least one of polymethyl acrylate, ethyl cellulose, polyethylene, polyvinyl butyral, and polyisobutylene.

[0026] Preferably, the ceramic layers have 4 groups, each group of the ceramic layers has 1 ceramic layer, wherein in the order of stacking from bottom to top, the average pore size of the micropores in each layer of ceramic layers has a gradient change from large to small, the pore size of the micropores in the first layer of ceramic layers is 40 to 50 um, the pore size of the micropores in the second layer of ceramic layers is 30 to 40 um, the pore size of the micropores in the third layer of ceramic layers is 20 to 30 um, and the pore size of the micropores in the fourth layer of ceramic layers is 10 to 20 um.

[0027] Preferably, the four layers of the ceramic green body are stacked up and pressed into one body, and then the binder is removed and sintered. After sintering, one layer of the ceramic green body forms one layer of the ceramic sheet. In the order of stacking from bottom to top, the first layer of the ceramic green body contains 40 to 46 parts by weight of aggregate, the average particle size of the aggregate is 70 to 75 μm, the weight of the pore-forming agent is 25 to 28 parts, and the average particle size of the pore-forming agent is 40 to 50 μm; the second layer of the ceramic green body contains 45 to 50 parts by weight of aggregate, the average particle size of the aggregate is 40 to 60 μm. m, the weight portion of the pore-forming agent is 20 to 25 parts, and the average particle size of the pore-forming agent is 40 to 50 μm; the weight portion of the aggregate contained in the third layer of ceramic green body is 40 to 48 parts, the average particle size of the aggregate is 15 to 30 μm, the weight portion of the pore-forming agent is 25 to 30 parts, and the average particle size of the pore-forming agent is 35 to 40 μm; the weight portion of the aggregate contained in the fourth layer of ceramic green body is 35 to 45 parts, the average particle size of the aggregate is 10 to 20 μm, the weight portion of the pore-forming agent is 25 to 30 parts, and the average particle size of the pore-forming agent is 35 to 40 μm.

[0028] Preferably, the ceramic layers have 4 groups, each group of the ceramic layers has 1 ceramic layer, wherein in the order of stacking from bottom to top, the average pore size of the micropores in each layer of ceramic layers has a pattern of alternating size changes, the pore size of the micropores in the first layer of ceramic layers is 40 to 50 um, the pore size of the micropores in the second layer of ceramic layers is 30 to 40 um, the pore size of the micropores in the third layer of ceramic layers is 40 to 50 um, and the pore size of the micropores in the fourth layer of ceramic layers is 10 to 20 um.

[0029] Preferably, the four layers of the ceramic green body are stacked up and pressed into one body, and then the binder is removed and sintered. After sintering, one layer of the ceramic green body forms one layer of the ceramic sheet. In the order of stacking from bottom to top, the first layer of the ceramic green body contains 40 to 46 parts by weight of aggregate, the average particle size of the aggregate is 70 to 75 μm, the weight of the pore-forming agent is 25 to 28 parts, and the average particle size of the pore-forming agent is 40 to 50 μm; the second layer of the ceramic green body contains 45 to 50 parts by weight of aggregate, the average particle size of the aggregate is 40 to 60 μm. m, the weight portion of the pore-forming agent is 20 to 25 parts, and the average particle size of the pore-forming agent is 40 to 50 μm; the weight portion of the aggregate contained in the third layer of ceramic green body is 40 to 46 parts, the average particle size of the aggregate is 70 to 75 μm, the weight portion of the pore-forming agent is 25 to 28 parts, and the average particle size of the pore-forming agent is 40 to 50 μm; the weight portion of the aggregate contained in the fourth layer of ceramic green body is 35 to 45 parts, the average particle size of the aggregate is 10 to 20 μm, the weight portion of the pore-forming agent is 25 to 30 parts, and the average particle size of the pore-forming agent is 35 to 40 μm.

[0030] Preferably, there are 3 groups of ceramic sheets, each group of ceramic sheets has 2 ceramic sheets, and the total number of sheets is 6. Among them, in order from bottom to top, the average pore size of the micropores in each layer of ceramic sheets has a gradient change from large to small. The pore size of the micropores in the first group of ceramic sheets is 35~50um, the pore size of the micropores in the second group of ceramic sheets is 20~35um, and the pore size of the micropores in the third group of ceramic sheets is 10~20um.

[0031] Preferably, two layers of the same ceramic green body are stacked up and down to form a group of ceramic green bodies, and three groups of different ceramic green bodies are stacked up and down to form a whole, and then the binder is removed and sintered. After sintering, one layer of the ceramic green body forms a layer of the ceramic sheet. In the order of stacking from bottom to top, the weight parts of the aggregate contained in the first group of ceramic green bodies are 40 to 46 parts, the average particle size of the aggregate is 60 to 75 μm, the weight parts of the pore former are 25 to 30 parts, and the average particle size of the pore former is 100 μm. The diameter is 40-50um; the weight parts of aggregate contained in the second group of ceramic green bodies are 40-48 parts, the average particle size of aggregate is 15-50um, the weight parts of pore former are 25-30 parts, and the average particle size of pore former is 35-40um; the weight parts of aggregate contained in the third group of ceramic green bodies are 35-45 parts, the average particle size of aggregate is 10-20um, the weight parts of pore former are 25-30 parts, and the average particle size of pore former is 35-40um.

[0032] Preferably, there are 4 groups of ceramic sheets, each group of ceramic sheets has 2 ceramic sheets, and the total number of sheets is 8. Among them, in order from bottom to top, the average pore size of the micropores in each layer of ceramic sheets has a gradient change from large to small. The pore size of the micropores in the first group of ceramic sheets is 40-50um, the pore size of the micropores in the second group of ceramic sheets is 30-40um, the pore size of the micropores in the third group of ceramic sheets is 20-30um, and the pore size of the micropores in the fourth group of ceramic sheets is 10-20um.

[0033] Preferably, two layers of the same ceramic green body are stacked up and down to form a group of ceramic green bodies, and four groups of different ceramic green bodies are pressed into one body and then debonded and sintered. After sintering, one layer of the ceramic green body forms a layer of the ceramic sheet. The ceramic green body is made by tape-casting ceramic slurry through a tape-casting process. In the order of stacking from bottom to top, the weight parts of aggregate contained in the first group of ceramic green bodies are 40 to 46 parts, the average particle size of the aggregate is 70 to 75 μm, the weight parts of the pore-forming agent are 25 to 28 parts, and the average particle size of the pore-forming agent is 40 to 50 μm; the weight parts of aggregate contained in the second group of ceramic green bodies are The weight of the aggregate in the first group is 45-50 parts, the average particle size of the aggregate is 40-60um, the weight of the pore-forming agent is 20-25 parts, and the average particle size of the pore-forming agent is 40-50um; the weight of the aggregate in the third group of ceramic green bodies is 40-48 parts, the average particle size of the aggregate is 15-30um, the weight of the pore-forming agent is 25-30 parts, and the average particle size of the pore-forming agent is 35-40um; the weight of the aggregate in the fourth group of ceramic green bodies is 35-45 parts, the average particle size of the aggregate is 10-20um, the weight of the pore-forming agent is 25-30 parts, and the average particle size of the pore-forming agent is 35-40um.

[0034] Another technical solution of the present invention is a multi-layer porous ceramic atomization core, comprising the multi-layer porous ceramic substrate as described above, wherein one of the upper and lower surfaces of the multi-layer porous ceramic substrate is set as an atomization surface, and the other surface is set as a liquid guide surface. Electrode layers are respectively provided at both ends of the atomization surface, and the electrode layers are made by screen printing the metal slurry and sintering. A metal heating layer is also provided on the atomization surface, and the metal heating layer is made by a metal sputtering coating process or by screen printing another metal slurry and then sintering. The metal heating layer is electrically connected to the electrode layer.

[0035] Preferably, the upper and lower surfaces of the multi-layer porous ceramic substrate are each selected so as to have a smaller pore size of micropores as the atomizing surface, and the other surface is selected so as to have a liquid guiding surface. Beneficial effects

[0036] Unlike existing porous ceramics with a single pore structure, the present invention uses a tape casting process to prepare multiple groups of ceramic green sheets with a continuously varying particle size structure. These green sheets are then stacked, pressed, and fired to produce a porous ceramic matrix with multiple layers of varying pore sizes. Specifically, a multi-layer porous ceramic matrix with a gradient pore size structure can be formed. The green sheets are formed using a multi-layer lamination process. Compared to a single-stage forming process, the pressing and sintering of the multi-layer ceramic green sheets creates microscopic interlayer interfaces. The pore size of these interlayer interfaces lies between the pore sizes of the two layers, providing a transitional and buffering effect for the transport of the atomized liquid, facilitating its storage and transmission. In addition, multi-layer ceramic sheets can be stacked to prepare porous ceramics with a gradient pore structure. When applied to the atomization core of an electronic cigarette, the ceramic pore structure can be gradiently adjusted according to the ceramic sheets based on different heating methods and different viscosities of the smoke liquid. The porosity and pore size from the liquid guide surface to the atomization surface are adjusted layer by layer, so that the liquid supply and atomization of the porous ceramic matrix are balanced, achieving the advantages of both fast liquid guide and fine atomization, and improving the atomization experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] FIG1 is a cross-sectional view of a multi-layer porous ceramic substrate according to a first embodiment of the present invention;

[0038] FIG2 is a perspective schematic diagram of four layers of ceramic green sheets stacked in accordance with Example 1 of the present invention;

[0039] FIG3 is a cross-sectional view of a multi-layer porous ceramic substrate according to a second embodiment of the present invention;

[0040] FIG4 is a perspective schematic diagram of four layers of ceramic green sheets stacked in accordance with a second embodiment of the present invention;

[0041] FIG5 is a cross-sectional view of a multi-layer porous ceramic substrate according to a third embodiment of the present invention;

[0042] FIG6 is a three-dimensional schematic diagram of two layers of ceramic green sheets stacked as a group according to Example 3 of the present invention;

[0043] FIG7 is a three-dimensional schematic diagram of three groups of ceramic green sheets stacked in Example 3 of the present invention;

[0044] FIG8 is a cross-sectional view of a multi-layer porous ceramic substrate according to a fourth embodiment of the present invention;

[0045] FIG9 is a three-dimensional schematic diagram of four groups of ceramic green sheets stacked in accordance with a fourth embodiment of the present invention;

[0046] FIG10 is an exploded perspective view of a multi-layered porous ceramic atomizing core according to Embodiments 5 and 6 of the present invention;

[0047] FIG11 is an inverted three-dimensional exploded view of the multi-layer porous ceramic atomizing core according to the fifth and sixth embodiments of the present invention. Best Mode for Carrying Out the Invention

[0048] To facilitate description and better illustrate the present invention and its embodiments, terms or descriptions indicating directions or positions, such as "upper," "lower," "upright," and "inverted," herein refer to the orientation or position of the devices or components in the accompanying drawings and are not intended to limit the devices, components, or parts indicated to a specific orientation, or to their construction and operation in a specific orientation. In the event of a change in orientation or position, the above-mentioned directional terms will also change accordingly. Furthermore, terms such as "first," "second," etc., are primarily used to distinguish different devices, components, or parts and are not intended to indicate or imply the relative importance, absolute order, or quantity of the devices, components, or parts indicated.

[0049] The present invention provides a multi-layer porous ceramic matrix, which is composed of several groups, such as 3 to 10 groups, of ceramic sheets stacked and sintered into one body. Each group of ceramic sheets includes one to several layers, such as one to three layers. Each layer of ceramic sheets has bubble-like micropores evenly distributed therein. The average pore size of the micropores in different layers of the same group is the same, while the average pore size of the micropores in different groups of ceramic sheets is different. The average pore size of the micropores in each group of ceramic sheets, arranged from bottom to top, has a regular pattern of alternating size changes or a gradient change from large to small. The micropores are spherical or nearly spherical bubble-like micropores, which are relatively close to each other. Some adjacent micropores are connected by tiny through-holes. Therefore, the entire multi-layer porous ceramic matrix can be used as a liquid conductor, which is used to absorb liquid substances from one side and conduct them to the other side after adsorption, penetration, and flow through the micropores.

[0050] In addition, the above-mentioned several groups of ceramic sheets are arranged in a bottom-up order, and the average pore size of the micropores in each group of ceramic sheets has a pattern of alternating size or gradient change from large to small. In other embodiments, the order of arrangement when stacking the ceramic green sheets is based on the average particle size of the aggregate and / or pore-forming agent, that is, based on the average particle size of the aggregate and / or pore-forming agent in the ceramic green sheets, and can also be arranged from small to large, or two large and one small, or two small and one large, or the same size and then alternating in size, so that the size of the micropores of each layer of ceramic sheets after production is also arranged according to the above pattern.

[0051] The multi-layered porous ceramic substrate of the present invention has micropores within each ceramic layer with an average pore diameter of 10 to 50 μm, a porosity of 40% to 65%, and a thickness of 0.1 to 0.5 mm for each ceramic layer. These micropore diameters and ceramic layer thickness structure ensure that the multi-layered porous ceramic substrate has good conductivity for conducting liquid substances under external forces such as suction, while also preventing excessive flow and maintaining a certain balance. In the absence of external forces such as suction, the micropores maintain a certain tension, allowing the liquid substances to be adsorbed and held in place without naturally flowing and leaking. The multi-layered porous ceramic substrate of the present invention can be used as a liquid conductor for conducting atomized liquids.

[0052] In the present invention, the average pore size of the micropores of each ceramic layer in the above-mentioned multi-layer porous ceramic matrix is ​​10 to 50 um, which means but is not limited to any value between 10 and 50 um, and\or 10 to 20 um, and\or 20 to 30 um, and\or 30 to 40 um, and\or 40 to 50 um, and\or 15 to 45 um, and\or 20 to 40 um.

[0053] The porosity of the micropores of each ceramic layer of the multi-layer porous ceramic matrix is ​​40%-65%, which means but is not limited to any value between 40%-65%, and\or 40%-45%, and\or 45%-50%, and\or 50%-55%, and\or 55%-60%, and\or 60%-65%, and\or 45-60%, and\or 48-56%.

[0054] The thickness of each ceramic layer of the multi-layer porous ceramic matrix is ​​0.1 to 0.5 mm, which includes but is not limited to any value between 0.1 and 0.5 mm, and\or 0.1 mm, and\or 0.2 mm, and\or 0.3 mm, and\or 0.4 mm, and\or 0.5 mm, and\or 0.1 to 0.25 mm, and or 0.2 to 0.4 mm, and or 0.25 to 0.5 mm.

[0055] In order to obtain a multi-layer porous ceramic matrix with the above-mentioned parameters, the multi-layer porous ceramic matrix of the present invention is manufactured by stacking 1 to 3 layers of the same flaky ceramic green embryos up and down to form a group of ceramic green embryos, and then stacking 3 to 10 groups of ceramic green embryos up and down and pressing them into one body, and then debinding and sintering them to obtain a multi-layer porous ceramic matrix. After sintering, one layer of the ceramic green embryos constitutes one layer of the ceramic layer.

[0056] In the embodiment of the present invention, the overall thickness of the multi-layer porous ceramic substrate after sintering is generally between 1 and 6 mm.

[0057] The ceramic green body is made of a tape-cast ceramic slurry through a tape-casting process. The components of the tape-cast ceramic slurry include, by weight, 40 to 65 parts of ceramic powder, 30 to 50 parts of solvent, 0.1 to 3 parts of slurry dispersant, 1 to 8 parts of plasticizer, and 1 to 10 parts of binder. The components of the ceramic powder include, by weight, 25 to 55 parts of aggregate, 5 to 40 parts of pore-forming agent, 5 to 19 parts of sintering aid, and 5 to 35 parts of powder dispersant. The average particle size of the aggregate and pore-forming agent contained in different layers of the ceramic green bodies of the same group is the same, while the average particle size of the aggregate and / or pore-forming agent contained in different groups of ceramic green bodies is different. The average particle sizes of the aggregate and / or pore-forming agent contained in each group of ceramic green bodies are selected to be different, including selecting different average particle sizes of the aggregate, different average particle sizes of the pore-forming agent, or different average particle sizes of both the aggregate and the pore-forming agent. Such selection is intended to result in different micropore diameters within different groups of ceramic sheets formed after sintering the different groups of ceramic green bodies.

[0058] When manufacturing the multi-layer porous ceramic substrate of the present invention, the thickness of each layer of the ceramic green body made by the casting process is 0.1 to 0.6 mm, which means but is not limited to: any value between 0.1 and 0.6 mm, and\or 0.1 mm, and\or 0.2 mm, and\or 0.3 mm, and\or 0.4 mm, and\or 0.5 mm, and\or 0.6 mm, and\or 0.1 to 0.3 mm, and or 0.25 to 0.45 mm, and or 0.3 to 0.6 mm.

[0059] Among them, the aggregate is the main material that forms the skeleton of the multi-layer porous ceramic matrix, including at least one of kaolin, diatomaceous earth, alumina, silicon nitride, silicon carbide, quartz sand, glass sand, clay, feldspar powder, fused quartz, cordierite, and mullite. In the present invention, due to the need to produce micropores in the ceramic matrix, certain requirements are placed on the particle size of the aggregate. The average particle size of the aggregate is selected to be 5 to 100 um, which includes but is not limited to: any value between 5 and 100 um, and\or 5 to 10 um, and\or 10 to 20 um, and\or 20 to 30 um, and\or 30 to 40 um, and\or 40 to 50 um, and\or 50 to 60 um, and\or 60 to 70 um, and\or 70 to 80 um, and\or 80 to 90 um, and\or 90 to 100 um, and\or 5 to 50 um, and\or 10 to 30 um, and\or 50 to 100 um, and\or 55 to 85 um.

[0060] The pore former is a material that vaporizes and evaporates during sintering to form micropores in the porous ceramic matrix, including at least one of graphite, starch, wood powder, flour, bean powder, polystyrene microspheres, polymethyl methacrylate microspheres, sucrose, and fiber. In the present invention, due to the need to produce micropores in the ceramic matrix, there are certain requirements for the particle size of the pore-forming agent. The average particle size of the pore-forming agent is selected to be 5-100 μm, which includes but is not limited to: any value between 5-100 μm, and\or 5-10 μm, and\or 10-20 μm, and\or 20-30 μm, and\or 30-40 μm, and\or 40-50 μm, and\or 50-60 μm, and\or 60-70 μm, and\or 70-80 μm, and\or 80-90 μm, and\or 90-100 μm, and\or 5-50 μm, and\or 50-100 μm, and\or 15-80 μm, and\or 25-60 μm, and\or 55-95 μm, and\or 65-85 μm.

[0061] The sintering aid is a material used to bond aggregates and help sinter at a suitable temperature to form a porous ceramic matrix, including at least one of boron oxide, sodium silicate, silicon oxide, potassium oxide, lithium oxide, barium oxide, magnesium oxide, calcium oxide, iron oxide, titanium oxide, zinc oxide, and zirconium oxide.

[0062] The powder dispersant is a material used to promote uniform dispersion of aggregates and prevent precipitation and accumulation, including at least one of paraffin, beeswax, boric acid, oleic acid, stearic acid, polyethylene, polypropylene, polyvinyl acetate, polyvinyl acetal, ethylene-vinyl acetate copolymer resin, vinyl chloride-vinyl acetate copolymer resin, perchlorethylene resin, polyacrylate, and polyamide.

[0063] The solvent is a material used to convert ceramic powder into a fluid, and includes at least one of ethanol, isopropyl alcohol, acetone, butanone, xylene, trichloroethylene, ethyl acetate, and butyl acetate.

[0064] The slurry dispersant is a material used to disperse ceramic powder in a solvent, and includes at least one of oleic acid, boric acid, linseed oil, castor oil, stearic acid, and triolein.

[0065] The plasticizer is a material used to improve the plasticity of the ceramic green body, and includes at least one of polyethylene glycol and dibutyl phthalate.

[0066] The binder is a material used to improve the strength of the ceramic green body, and includes at least one of polymethyl acrylate, ethyl cellulose, polyethylene, polyvinyl butyral, and polyisobutylene.

[0067] When manufacturing the multi-layer porous ceramic substrate of the present invention, the above components of the ceramic slurry are cast:

[0068] The 40 to 65 parts of ceramic powder include but are not limited to: any integer between 40 and 65 parts, and\or 40 to 45 parts, and\or 45 to 50 parts, and\or 50 to 55 parts; and\or 55 to 60 parts, and\or 60 to 65 parts, and\or 45 to 55 parts.

[0069] Wherein 30-50 parts of solvent refers to but is not limited to: any integer between 30-50 parts, and\or 31-35 parts, and\or 35-40 parts, and\or 40-45 parts, and\or 45-50 parts, and\or 35-45 parts;

[0070] Wherein, 0.1 to 3 parts of slurry dispersant refers to but is not limited to: 0.1 part, 0.2 part, 0.3 part, 0.4 part, 0.5 part, 0.6 part, 0.7 part, 0.8 part, 0.9 part, 1 part, 1.1 part...3 parts, and\or 0.1 to 1 part, and\or 1.1 to 2 parts, and\or 2.1 to 3 parts;

[0071] Wherein 1 to 8 parts of plasticizer refers to but is not limited to: any integer between 1 to 8 parts, and\or 1 to 3 parts, and\or 3 to 5 parts, and\or 1 to 5 parts, and\or 5 to 8 parts;

[0072] The term "1 to 10 parts of binder" refers to but is not limited to any integer between 1 and 10, and / or 1 to 3, and / or 3 to 5, and / or 5 to 8, and / or 8 to 10, and / or 3 to 8.

[0073] When manufacturing the multi-layered porous ceramic substrate of the present invention, the above components of the ceramic powder are:

[0074] Wherein, 25 to 55 parts of aggregate refers to but is not limited to: any integer between 25 and 55 parts, and\or 25 to 30 parts, and\or 30 to 35 parts, and\or 35 to 40 parts, and\or 40 to 45 parts, and\or 45 to 50 parts, and\or 50 to 55 parts, and\or 35 to 55 parts;

[0075] The pore-forming agent of 5 to 40 parts refers to but is not limited to: any integer between 5 and 40 parts, and\or 5 to 10 parts, and\or 10 to 15 parts, and\or 15 to 20 parts, and\or 20 to 25 parts, and\or 25 to 30 parts, and\or 30 to 35 parts, and\or 35 to 40 parts;

[0076] The sintering aid of 5 to 19 parts refers to but is not limited to: any integer between 5 and 19 parts, and\or 5 to 10 parts, and\or 10 to 15 parts, and\or 15 to 19 parts;

[0077] The powder dispersant of 5 to 35 parts refers to but is not limited to: any integer between 5 and 35 parts, and\or 5 to 10 parts, and\or 10 to 15 parts, and\or 15 to 20 parts, and\or 20 to 25 parts, and\or 25 to 30 parts, and\or 30 to 35 parts.

[0078] Unlike existing porous ceramics with a single pore structure, the present invention utilizes a tape-casting process to prepare multiple groups of ceramic green sheets with continuously varying particle sizes. These green sheets are then laminated and fired to produce a porous ceramic matrix with multiple layers of varying pore sizes. Specifically, a multi-layer porous ceramic matrix with a gradient pore size structure can be formed. The green sheets are formed using a multi-layer lamination process. Compared to a single-stage molding process, the pressing and sintering of the multi-layer ceramic green sheets creates microscopic interlayer interfaces. The pore size of these interlayer interfaces lies between the pore sizes of the two layers, providing a transitional and buffering effect for the transport of the atomized liquid, facilitating its storage and transmission. In addition, multi-layer ceramic sheets can be stacked to prepare porous ceramics with a gradient pore structure. When applied to the atomization core of an electronic cigarette, the ceramic pore structure can be gradiently adjusted according to the ceramic sheets based on different heating methods and different viscosities of the smoke liquid. The porosity and pore size from the liquid guide surface to the atomization surface are adjusted layer by layer, so that the liquid supply and atomization of the porous ceramic matrix are balanced, achieving the advantages of both fast liquid guide and fine atomization, and improving the atomization experience.

[0079] It should be noted that during the manufacture of the multi-layered porous ceramic substrate of the present invention, due to the stacking and pressing of the ceramic green sheets, the thickness of each layer of the ceramic green sheets will be slightly greater than the thickness of each layer of the ceramic sheets after sintering. The multi-layered porous ceramic substrate after sintering is actually a whole, and no obvious stratification can be seen from the appearance and cross-section, which is generally difficult to distinguish with the naked eye. The number of groups and the layer-by-layer analysis of the ceramic sheets described in this article are simply grouping and stratification based on the size of the micropores inside each group and each layer of the ceramic sheets. Modes for Carrying Out the Invention

[0080] The present invention will be described in detail below through specific examples. Example 1:

[0081] As shown in Figure 1, a multi-layer porous ceramic matrix 10 of the present invention is composed of four groups of ceramic layers stacked up and down and sintered into one. The four groups of ceramic layers include, in order from bottom to top, a first group of ceramic layers 110, a second group of ceramic layers 120, a third group of ceramic layers 130, and a fourth group of ceramic layers 140. Each group of ceramic layers is composed of one layer of ceramic layers 100, and each layer of ceramic layers 100 is uniformly distributed with bubble-shaped micropores (not shown in the figure). The average pore size of the micropores in each group or layer of ceramic layers is different. The average pore size of the micropores in each group of ceramic layers has a gradient change from large to small in the four groups of ceramic layers in order from bottom to top, that is, from the first group of ceramic layers 110 to the fourth group of ceramic layers 140, the average pore size of the micropores in each group of ceramic layers has a gradient change from large to small. In order of stacking from bottom to top, the micropores in the first group of ceramic sheets 110 have a diameter of 40-50 μm, the micropores in the second group of ceramic sheets 120 have a diameter of 30-40 μm, the micropores in the third group of ceramic sheets 130 have a diameter of 20-30 μm, and the micropores in the fourth group of ceramic sheets 140 have a diameter of 10-20 μm. In Figure 1, denser shaded areas represent smaller pores, while looser shaded areas represent larger pores.

[0082] In the multi-layer porous ceramic substrate of this embodiment, the porosity of the micropores in each ceramic layer is 40%-65%, and the thickness of each ceramic layer is 0.5 mm.

[0083] As shown in FIG2 , in order to obtain a multi-layer porous ceramic substrate 10 having the above-mentioned parameters, in this embodiment, the multi-layer porous ceramic substrate 10 is manufactured by stacking four layers of flaky ceramic green sheets 11, 12, 13, and 14 into four groups of ceramic green sheets, pressing them into one body, and then debinding and sintering them. After sintering, one layer of the ceramic green sheets 11 (or 12, 13, and 14) forms one layer of the ceramic sheet 110 (or 120, 130, and 140). The ceramic green sheets 11, 12, 13, and 14 are manufactured by a tape-casting process using a tape-casting ceramic slurry. The components of the tape-cast ceramic slurry include, by weight, 40 to 65 parts of ceramic powder, 30 to 50 parts of solvent, 0.1 to 3 parts of slurry dispersant, 1 to 8 parts of plasticizer, and 1 to 10 parts of binder. The components of the ceramic powder include, by weight, 35 to 50 parts of aggregate, 20 to 30 parts of pore former, 5 to 19 parts of sintering aid, and 5 to 35 parts of powder dispersant. The average particle size of the aggregate and pore former contained in different layers of the ceramic green bodies of the same group is the same, and the average particle size of the aggregate and / or pore former contained in different groups of ceramic green bodies is different.

[0084] In this embodiment, the ceramic green body is stacked from bottom to top. The first layer of ceramic green body 11 contains 40 to 46 parts by weight of aggregate, with an average particle size of 70 to 75 μm, and 25 to 28 parts by weight of pore former, with an average particle size of 40 to 50 μm. The second layer of ceramic green body 12 contains 45 to 50 parts by weight of aggregate, with an average particle size of 40 to 60 μm, and 20 to 25 parts by weight of pore former, with an average particle size of 40 to 60 μm. The diameter is 40 to 50 μm; the weight portion of the aggregate contained in the third layer of ceramic green body 13 is 40 to 48 parts, the average particle size of the aggregate is 15 to 30 μm, the weight portion of the pore former is 25 to 30 parts, and the average particle size of the pore former is 35 to 40 μm; the weight portion of the aggregate contained in the fourth layer of ceramic green body 14 is 35 to 45 parts, the average particle size of the aggregate is 10 to 20 μm, the weight portion of the pore former is 25 to 30 parts, and the average particle size of the pore former is 35 to 40 μm.

[0085] In this embodiment, the thickness of each layer of ceramic green body is 0.6 mm.

[0086] In this embodiment, the aggregate is the main material forming the skeleton of the multi-layer porous ceramic matrix, and is a mixture of kaolin, diatomaceous earth, alumina, and silicon nitride.

[0087] In this embodiment, the pore-forming agent is a material that vaporizes and evaporates during sintering to form micropores in the porous ceramic matrix, and is made of a mixture of graphite, starch, and wood powder.

[0088] In this embodiment, the sintering aid is a material used to bond aggregates and help sinter at a suitable temperature to form a porous ceramic matrix, and is composed of a mixture of boron oxide, sodium silicate, and potassium oxide.

[0089] In this embodiment, the powder dispersant is a material used to promote uniform dispersion of aggregates and prevent precipitation and accumulation, and is made of a mixture of paraffin, boric acid, and polyethylene.

[0090] In this embodiment, the solvent is a material used to convert ceramic powder into a fluid, and is a mixture of ethanol, isopropyl alcohol, and acetone.

[0091] In this embodiment, the slurry dispersant is a material used to disperse ceramic powder in a solvent, and is a mixture of boric acid and linseed oil.

[0092] In this embodiment, the plasticizer is a material used to improve the plasticity of the ceramic green body, and is composed of polyethylene glycol.

[0093] In this embodiment, the binder is a material used to improve the strength of the ceramic green body, and is a mixture of polymethyl acrylate and ethyl cellulose.

[0094] Example 2:

[0095] As shown in Figure 3, a multi-layer porous ceramic matrix 20 of the present invention is composed of four groups of ceramic layers stacked up and down and sintered into one, the four groups of ceramic layers include a first group of ceramic layers 210, a second group of ceramic layers 220, a third group of ceramic layers 230, and a fourth group of ceramic layers 240. Each group of ceramic layers is composed of one layer of ceramic layers 210, or 220, or 230, or 240, and each layer of ceramic layers is uniformly distributed with bubble-shaped micropores (not shown in the figure), wherein the average pore size of the micropores in each group of ceramic layers is different. The four groups of ceramic layers are arranged in a bottom-up order, and the average pore size of the micropores in each group of ceramic layers has a pattern of alternating size changes, that is, from the first group of ceramic layers 210 to the fourth group of ceramic layers 240, the average pore size of the micropores in each group of ceramic layers has a pattern of alternating size changes. In order of stacking from bottom to top, the micropores in the first group of ceramic sheets 210 have a diameter of 40-50 μm, the micropores in the second group of ceramic sheets 220 have a diameter of 30-40 μm, the micropores in the third group of ceramic sheets 230 have a diameter of 40-50 μm, and the micropores in the fourth group of ceramic sheets 240 have a diameter of 10-20 μm. In Figure 3, denser shaded areas represent smaller pores, while looser shaded areas represent larger pores.

[0096] As shown in FIG4 , in order to obtain a multi-layer porous ceramic substrate 20 having the above parameters, in this embodiment, the multi-layer porous ceramic substrate 20 is manufactured by stacking four layers of flaky ceramic green sheets 21, 22, 23, and 24 into four groups of ceramic green sheets, pressing them into one body, and then debinding and sintering them. After sintering, a layer of ceramic green sheet 21 (or 22, 23, and 24) forms a layer of ceramic sheet 210 (or 220, 230, and 240). The ceramic green sheets are made by tape-casting ceramic slurry through a tape-casting process. The components of the material include, by weight, 40 to 65 parts of ceramic powder, 30 to 50 parts of solvent, 0.1 to 3 parts of slurry dispersant, 1 to 8 parts of plasticizer and 1 to 10 parts of binder, wherein the components of the ceramic powder include, by weight, 35 to 50 parts of aggregate, 20 to 30 parts of pore former, 5 to 19 parts of sintering aid and 5 to 35 parts of powder dispersant, wherein the average particle size of the aggregate and pore former contained in different layers of the ceramic green bodies of the same group is the same, and the average particle size of the aggregate and / or pore former contained in different groups of ceramic green bodies is different.

[0097] In this embodiment, the ceramic green body is stacked from bottom to top. The first layer of ceramic green body contains 40 to 46 parts by weight of aggregate, the average particle size of the aggregate is 70 to 75 μm, the weight of the pore former is 25 to 28 parts, and the average particle size of the pore former is 40 to 50 μm. The second layer of ceramic green body contains 45 to 50 parts by weight of aggregate, the average particle size of the aggregate is 40 to 60 μm, the weight of the pore former is 20 to 25 parts, and the average particle size of the pore former is 20 to 30 μm. The particle size is 40 to 50 μm; the weight portion of the aggregate contained in the third layer of ceramic green body is 40 to 46 parts, the average particle size of the aggregate is 70 to 75 μm, the weight portion of the pore-forming agent is 25 to 28 parts, and the average particle size of the pore-forming agent is 40 to 50 μm; the weight portion of the aggregate contained in the fourth layer of ceramic green body is 35 to 45 parts, the average particle size of the aggregate is 10 to 20 μm, the weight portion of the pore-forming agent is 25 to 30 parts, and the average particle size of the pore-forming agent is 35 to 40 μm.

[0098] In the multi-layer porous ceramic substrate of this embodiment, the porosity of the micropores in each ceramic layer is 40%-65%, and the thickness of each ceramic layer is 0.5 mm. In this embodiment, the thickness of each ceramic green body is 0.6 mm.

[0099] The remaining technical features of this embodiment are basically the same as those of the first embodiment and will not be repeated here.

[0100] Example 3:

[0101] As shown in Figure 5, a multi-layer porous ceramic matrix 30 of this embodiment is composed of three groups of ceramic layers 310, 320, and 330 stacked up and sintered into one. Each group of ceramic layers includes two layers of ceramic layers 300. Bubble-shaped micropores are evenly distributed in each layer of ceramic layers 300. The average pore size of the micropores in different layers of the same group is the same, and the average pore size of the micropores in different groups of ceramic layers is different. The three groups of ceramic layers are arranged in a bottom-up order, and the average pore size of the micropores in each group of ceramic layers has a gradient change from large to small.

[0102] That is, there are three groups of ceramic layers: a first group of ceramic layers 310, a second group of ceramic layers 320, and a third group of ceramic layers 330. Each group of ceramic layers has two ceramic layers 300, for a total of six layers. From bottom to top, the micropores in the first group of ceramic layers 310 have a diameter of 35 to 50 μm, the micropores in the second group of ceramic layers 320 have a diameter of 20 to 35 μm, and the micropores in the third group of ceramic layers 330 have a diameter of 10 to 20 μm. In Figure 5, denser shaded lines represent smaller pores, while looser shaded lines represent larger pores.

[0103] As shown in Figures 5 to 7, the multi-layer porous ceramic substrate 30 of this embodiment is formed by stacking two layers of identical flaky ceramic green sheets 3 into a group of ceramic green sheets, and by stacking three groups of ceramic green sheets 31, 32, and 33 into a whole and then debonding and sintering. After sintering, one layer of ceramic green sheet 3 constitutes one ceramic sheet 300. Therefore, the multi-layer porous ceramic substrate 30 of this embodiment has six ceramic sheets 300. The ceramic green body 3 is made of a tape-cast ceramic slurry through a tape-casting process. The components of the tape-cast ceramic slurry include, by weight, 40 to 65 parts of ceramic powder, 30 to 50 parts of solvent, 0.1 to 3 parts of slurry dispersant, 1 to 8 parts of plasticizer, and 1 to 10 parts of binder. The components of the ceramic powder include, by weight, 35 to 48 parts of aggregate, 25 to 30 parts of pore-forming agent, 5 to 19 parts of sintering aid, and 5 to 35 parts of powder dispersant. The average particle size of the aggregate and pore-forming agent contained in different layers of the ceramic green bodies in the same group is the same, while the average particle size of the aggregate and / or pore-forming agent contained in different groups of ceramic green bodies is different.

[0104] Among them, in the order of stacking from bottom to top, the weight parts of aggregate contained in the first group of ceramic green bodies are 40 to 46 parts, the average particle size of aggregate is 60 to 75 μm, the weight parts of pore-forming agent are 25 to 30 parts, and the average particle size of pore-forming agent is 40 to 50 μm; the weight parts of aggregate contained in the second group of ceramic green bodies are 40 to 48 parts, the average particle size of aggregate is 15 to 50 μm, the weight parts of pore-forming agent are 25 to 30 parts, and the average particle size of pore-forming agent is 35 to 40 μm; the weight parts of aggregate contained in the third group of ceramic green bodies are 35 to 45 parts, the average particle size of aggregate is 10 to 20 μm, the weight parts of pore-forming agent are 25 to 30 parts, and the average particle size of pore-forming agent is 35 to 40 μm.

[0105] In the multi-layer porous ceramic substrate of this embodiment, the porosity of the micropores in each ceramic layer is 40%-65%, and the thickness of each ceramic layer is 0.35 mm. In this embodiment, the thickness of each ceramic green body is 0.4 mm.

[0106] The remaining technical features of this embodiment are basically the same as those of the first embodiment and will not be repeated here.

[0107] Example 4:

[0108] As shown in Figure 8, a multi-layer porous ceramic matrix 40 of this embodiment is composed of four groups of ceramic layers 410, 420, 430, and 440 stacked up and sintered into one. Each group of ceramic layers includes two layers of ceramic layers 400. Bubble-shaped micropores are evenly distributed in each layer of ceramic layers 400. The average pore size of the micropores in the same group of ceramic layers is the same, and the average pore size of the micropores in different groups of ceramic layers is different. The four groups of ceramic layers are arranged in a bottom-up order, and the average pore size of the micropores in each group of ceramic layers has a gradient change from large to small.

[0109] That is, the multi-layered porous ceramic substrate 40 of the present invention comprises four groups of ceramic layers, including a first group of ceramic layers 410, a second group of ceramic layers 420, a third group of ceramic layers 430, and a fourth group of ceramic layers 440. Each group of ceramic layers comprises two ceramic layers 400, for a total of eight layers. From bottom to top, the micropores in the first group of ceramic layers 410 have a diameter of 40 to 50 μm, the micropores in the second group of ceramic layers 420 have a diameter of 30 to 40 μm, the micropores in the third group of ceramic layers 430 have a diameter of 20 to 30 μm, and the micropores in the fourth group of ceramic layers 440 have a diameter of 10 to 20 μm. In FIG8 , denser shaded lines represent smaller pores, while looser shaded lines represent larger pores.

[0110] As shown in FIG9 , the multi-layer porous ceramic substrate 40 of this embodiment is formed by stacking two layers of identical sheet-shaped ceramic green sheets 4 to form a group of ceramic green sheets, and by stacking four groups of ceramic green sheets 41, 42, 43, and 44 to form a whole and then debinding and sintering. After sintering, a layer of ceramic green sheets 4 forms a layer of ceramic sheet 400. The ceramic green sheets 4 are formed by a tape-casting process using a tape-casting ceramic slurry. The components of the tape-casting ceramic slurry include, by weight, 40 to 65 parts of ceramic powder. parts, 30-50 parts of solvent, 0.1-3 parts of slurry dispersant, 1-8 parts of plasticizer and 1-10 parts of binder, wherein the components of the ceramic powder include, by weight, 35-48 parts of aggregate, 25-30 parts of pore former, 5-19 parts of sintering aid and 5-35 parts of powder dispersant, wherein the average particle size of the aggregate and the pore former contained in different layers of the ceramic green bodies of the same group is the same, and the average particle size of the aggregate and / or pore former contained in different groups of ceramic green bodies is different.

[0111] In the order of stacking from bottom to top, the first group of ceramic green bodies contains 40 to 46 parts by weight of aggregate, with an average particle size of 70 to 75 μm, and 25 to 28 parts by weight of pore former, with an average particle size of 40 to 50 μm; the second group of ceramic green bodies contains 45 to 50 parts by weight of aggregate, with an average particle size of 40 to 60 μm, and 20 to 25 parts by weight of pore former, with an average particle size of 4 0~50um; the weight parts of aggregate contained in the third group of ceramic green bodies are 40~48 parts, the average particle size of the aggregate is 15~30um, the weight parts of the pore-forming agent are 25~30 parts, and the average particle size of the pore-forming agent is 35~40um; the weight parts of aggregate contained in the fourth group of ceramic green bodies are 35~45 parts, the average particle size of the aggregate is 10~20um, the weight parts of the pore-forming agent are 25~30 parts, and the average particle size of the pore-forming agent is 35~40um.

[0112] In the multi-layer porous ceramic substrate of this embodiment, the porosity of the micropores in each ceramic layer is 40%-65%, and the thickness of each ceramic layer is 0.25 mm. In this embodiment, the thickness of each ceramic green body is 0.3 mm.

[0113] The remaining technical features of this embodiment are basically the same as those of the first embodiment and will not be repeated here.

[0114] Example 5:

[0115] As shown in Figures 10 and 11, this embodiment provides a multi-layer porous ceramic atomizing core, which includes a multi-layer porous ceramic substrate 50, which can be used as a liquid guide for the atomizing core. First, on the basis of the multi-layer porous ceramic substrate 50 of the above embodiment, one of the upper and lower surfaces of the multi-layer porous ceramic substrate is selected as the atomizing surface 51, and the other surface is used as the liquid guide surface 52. Electrode layers 53 are provided at both ends of the atomizing surface 51. The electrode layer is printed on both ends of the atomizing surface 51 by screen printing of metal slurry and sintered to obtain the electrode layer 53. A metal heating layer 54 is also provided on the atomizing surface 51. The metal heating layer 54 is obtained by a metal sputtering coating process or by a process of screen printing another metal slurry and then sintering. The metal heating layer 54 is electrically connected to the electrode layer 53. Both the upper and lower surfaces of the multi-layer porous ceramic matrix can be used as liquid guiding surfaces for introducing liquid substances, and the other surface is used as an atomizing surface for seeping out liquid substances. The metal heating layer 54 also has micropores or large through holes, so that the liquid substance seeping out of the atomizing surface 51 can continue to seep out through the metal heating layer, or provide gaseous substances for volatilization into the air. When the metal heating layer 54 is energized, it can heat, evaporate or atomize the liquid substance seeping out of the atomizing surface 51 to form an aerosol or aerosol, smoke. The electrode layer 53 is used to connect the two poles of the power supply to provide electrical energy for the metal heating layer 54.

[0116] Figure 10 of the accompanying drawings in this specification shows an upright, exploded perspective view of the multi-layered porous ceramic atomizer core of this embodiment, and Figure 11 shows an inverted, exploded perspective view of the multi-layered porous ceramic atomizer core of this embodiment. In actual use, the multi-layered porous ceramic atomizer core of the present invention is generally installed in the position shown in Figure 11 so that the atomized liquid can flow from top to bottom by gravity and be conducted to the metal heating layer. The position shown in Figure 10 is for the convenience of showing the electrode layer and metal heating layer in the exploded structure.

[0117] The multi-layer porous ceramic atomizing core of the present invention, in which the multi-layer porous ceramic matrix 50 serving as a liquid conductor, has bubble-shaped micropores uniformly distributed within each ceramic layer. The average pore size of the micropores within the same group of ceramic layers is the same, while the average pore size of the micropores within different groups of ceramic layers is different. The average pore size of the micropores within each group of ceramic layers, in order from bottom to top, has a pattern of alternating size changes or a gradient change from large to small. The micropores are spherical or nearly spherical bubble-shaped micropores, and the distance between the micropores is relatively close. Some adjacent micropores are connected by tiny through-holes. Therefore, the entire multi-layer porous ceramic matrix can serve as a liquid conductor, used to absorb liquid substances from one side and conduct them to the other side after adsorption, penetration, and flow through the micropores. The liquid-conducting structure of the multi-layered porous ceramic atomizer core of the present invention has the aforementioned micropore diameter and ceramic layer thickness structure, which ensures that the multi-layered porous ceramic matrix has good conductivity for conducting liquid substances under external forces such as suction, while preventing excessive flow and maintaining a certain balance. In the absence of external forces such as suction, the micropores have a certain tension, which allows for rapid absorption of liquid substances without causing natural flow and leakage. The multi-layered porous ceramic atomizer core of the present invention can be used in electronic cigarette atomizers to heat, evaporate, and atomize atomized liquid or electronic cigarette liquid within the electronic cigarette liquid storage chamber.

[0118] The present invention uses a tape casting process to prepare multiple groups of ceramic green sheets with continuously different particle size structures, and the multiple ceramic green sheets are stacked and pressed and fired to obtain a porous ceramic matrix with multiple layers of different pore sizes, especially a multi-layer porous ceramic matrix with a gradient pore size structure. The ceramic green sheet is formed by a multi-layer stacking method. Compared with the one-time molding process, after the multi-layer ceramic green sheet is pressed and sintered, an interlayer interface is generated at the microscopic level. The micropore size of the interlayer interface is between the micropore size of the two layers, which has a certain transition and buffering effect on the transmission of the atomized liquid, which is beneficial to the storage and transmission of the atomized liquid. In addition, the multi-layer ceramic sheet can be stacked to prepare a porous ceramic with a gradient pore size structure. When applied to the atomizer core of an electronic cigarette, the ceramic pore size structure can be gradiently adjusted according to the ceramic sheet according to different heating modes and different viscosities of the smoke liquid. The porosity and pore size are adjusted layer by layer from the liquid guide surface to the atomization surface, so that the liquid supply and atomization of the porous ceramic matrix are balanced, achieving the advantages of both fast liquid guide and fine atomization, and improving the atomization experience.

[0119] Example 6:

[0120] As shown in Figures 9 and 10, the multi-layer porous ceramic atomization core of the present invention is first based on the multi-layer porous ceramic substrate 50 in the above embodiment. The side with the smaller pore size of the micropores on the upper and lower surfaces of the multi-layer porous ceramic substrate is selected as the atomization surface 51, and the other side is set as the liquid guide surface 52. Electrode layers 53 are provided at both ends of the atomization surface 51. The electrode layer is printed on both ends of the atomization surface 51 by screen printing of metal slurry and sintering to obtain the electrode layer 53. A metal heating layer 54 is also provided on the atomization surface 51. The metal heating layer 54 is obtained by a metal sputtering coating process or by a process of screen printing another metal slurry and then sintering. In this embodiment, the side with a smaller pore size of the micropores is selected as the atomizing surface 51, and the other side is set as the liquid guiding surface 52, so that the atomized liquid is more easily absorbed by the liquid guiding surface. When it reaches the atomizing surface, due to the smaller micropore size, the seepage rate of the atomized liquid can be controlled, so that the liquid supply and atomization speeds are matched to better achieve a dynamic balance, thereby achieving the advantages of both fast liquid guiding and fine atomization, and improving the atomization experience of electronic cigarette atomizer users. Industrial Applicability

[0121] The above descriptions are merely preferred embodiments of the present invention. All equivalent changes and modifications made within the scope of the claims of the present invention shall fall within the scope of the claims of the present invention.

Claims

1. A multi-layered porous ceramic matrix, characterized in that, It is composed of several groups of ceramic sheet layers stacked and sintered together up and down. Each group of ceramic sheet layers includes 1 to several layers of ceramic sheet layers. In each layer of ceramic sheet layer, bubble-shaped micropores are evenly distributed. The average pore diameter of the micropores in the ceramic sheet layers of the same group and different layers is the same, and the average pore diameter of the micropores in the ceramic sheet layers of different groups is different. In the order from bottom to top of the several groups of ceramic sheet layers, the average pore diameter of the micropores in each group of ceramic sheet layers has a law of alternating large and small changes or gradient changes from large to small.

2. The multi-layered porous ceramic substrate according to claim 1, characterized in that, It is prepared by stacking 1 to several layers of sheet-shaped ceramic green bodies up and down to form a group of ceramic green bodies, and then stacking several groups of the ceramic green bodies up and down and pressing them into one body for debinding and sintering. One layer of the ceramic green body forms one layer of the ceramic sheet layer after sintering. The ceramic green body is prepared by a tape casting process using a tape casting ceramic slurry. The components of the tape casting ceramic slurry include 40 to 65 parts by weight of ceramic powder, 30 to 50 parts by weight of solvent, 0.1 to 3 parts by weight of slurry dispersant, 1 to 8 parts by weight of plasticizer, and 1 to 10 parts by weight of binder. Among them, the components of the ceramic powder include 25 to 55 parts by weight of aggregate, 5 to 40 parts by weight of pore former, 5 to 19 parts by weight of sintering aid, and 5 to 35 parts by weight of powder dispersant. The average particle sizes of the aggregate and pore former contained in the ceramic green bodies of the same group and different layers are the same, and the average particle sizes of the aggregate and / or pore former contained in the ceramic green bodies of different groups are different.

3. The multi-layered porous ceramic matrix according to claim 1, wherein, The average pore diameter of the micropores is 10 to 50 μm, or 15 to 45 μm, or 20 to 40 μm.

4. The multi-layered porous ceramic substrate according to claim 1, characterized in that, The porosity of the micropores is 40% - 65%, or 45 - 60%, or 48 - 56%.

5. The multi-layered porous ceramic substrate according to claim 1, wherein The thickness of each layer of the ceramic sheet layer is 0.1 to 0.5 mm, or 0.1 to 0.25 mm, or 0.2 to 0.4 mm, or 0.25 to 0.5 mm.

6. The multi-layer porous ceramic substrate according to claim 1, characterized in that The ceramic sheet layer has 2 to 10 groups, and each group of the ceramic sheet layer has 1 to 3 layers of ceramic sheet layers.

7. The multi-layered porous ceramic substrate according to claim 2, wherein The ceramic sheet layer has 2 to 5 groups, and each group of the ceramic sheet layer has 1 to 2 layers of ceramic sheet layers.

8. The multi-layered porous ceramic substrate according to claim 2, wherein The ceramic sheet layer has 3 groups or 4 groups, and each group of the ceramic sheet layer has 1 to 2 layers of ceramic sheet layers.

9. The multi-layered porous ceramic matrix according to claim 2, wherein The components of the ceramic green body include 45 to 55 parts by weight of the ceramic powder, 35 to 45 parts by weight of solvent, 0.1 to 1 part by weight of slurry dispersant, 1 to 5 parts by weight of plasticizer, and 3 to 8 parts by weight of binder.

10. The multi-layer porous ceramic matrix according to claim 2, characterized in that, The components of the ceramic powder include 35 to 55 parts by weight of the aggregate, 25 to 30 parts by weight of pore former, 15 to 19 parts by weight of sintering aid, and 5 to 10 parts by weight of powder dispersant.

11. The multi-layered porous ceramic substrate according to claim 2, wherein, The average particle size of the aggregate is 5 to 100 μm, or 5 to 50 μm, or 10 to 30 μm.

12. The multi-layered porous ceramic substrate according to claim 2, wherein, The average particle size of the pore former is 5 to 100 μm, or 15 to 80 μm, or 25 to 60 μm.

13. The multi-layered porous ceramic matrix according to claim 2, characterized in that, The thickness of each layer of the ceramic green body is 0.1 to 0.6 mm, or 0.1 to 0.3 mm, or 0.25 to 0.45 mm, or 0.3 to 0.6 mm.

14. The multi-layered porous ceramic substrate according to claim 2, characterized in that, The aggregate is the main material forming the skeleton of the multi-layer porous ceramic matrix, including at least one of kaolin, diatomite, alumina, silicon nitride, silicon carbide, quartz sand, glass sand, clay, feldspar powder, fused quartz, cordierite, and mullite.

15. The multi-layered porous ceramic substrate according to claim 2, characterized in that, The pore-forming agent is a material that vaporizes and evaporates during sintering to form micropores in the porous ceramic matrix, and includes at least one of graphite, starch, wood powder, flour, bean powder, polystyrene microspheres, polymethyl methacrylate microspheres, sucrose, and fibers.

16. The multi-layer porous ceramic substrate according to claim 2, wherein The sintering aid is a material that binds the aggregate and helps sinter to form a porous ceramic matrix at an appropriate temperature, and includes at least one of boron oxide, sodium silicate, silicon oxide, potassium oxide, lithium oxide, barium oxide, magnesium oxide, calcium oxide, iron oxide, titanium oxide, zinc oxide, and zirconium oxide.

17. The multi-layer porous ceramic matrix according to claim 2, wherein, The powder dispersant is a material that promotes the uniform dispersion of the aggregate and prevents precipitation and accumulation, and includes at least one of paraffin wax, beeswax, boric acid, oleic acid, stearic acid, polyethylene, polypropylene, polyvinyl acetate, polyvinyl acetal, ethylene-vinyl acetate copolymer resin, vinyl chloride-vinyl acetate copolymer resin, perchloroethylene resin, polyacrylate, and polyamide.

18. The multi-layered porous ceramic matrix according to claim 2, wherein, The solvent is a material that converts the ceramic powder into a fluid, and includes at least one of ethanol, isopropanol, acetone, methyl ethyl ketone, xylene, trichloroethylene, ethyl acetate, and butyl acetate.

19. The multi-layered porous ceramic substrate according to claim 2, wherein The slurry dispersant is a material that disperses the ceramic powder in the solvent, and includes at least one of oleic acid, boric acid, linseed oil, castor oil, stearic acid, and glyceryl trioleate.

20. The multi-layer porous ceramic matrix according to claim 2, wherein, The plasticizer is a material that improves the plasticity of the green ceramic body, and includes at least one of polyethylene glycol and dibutyl phthalate.

21. The multi-layer porous ceramic matrix according to claim 2, characterized in that, The binder is a material that improves the strength of the green ceramic body, and includes at least one of polymethyl acrylate, ethyl cellulose, polyethylene, polyvinyl butyral, and polyisobutylene.

22. The multi-layered porous ceramic substrate according to claim 8, characterized in that, There are 4 groups of the ceramic laminae, and each group of the ceramic laminae has 1 layer of ceramic lamina. Wherein, in the order of stacking from bottom to top, the average pore diameter of the micropores in each layer of the ceramic lamina has a gradient change rule from large to small. The pore diameter of the micropores in the first layer of the ceramic lamina is 40 - 50 μm, the pore diameter of the micropores in the second layer of the ceramic lamina is 30 - 40 μm, the pore diameter of the micropores in the third layer of the ceramic lamina is 20 - 30 μm, and the pore diameter of the micropores in the fourth layer of the ceramic lamina is 10 - 20 μm.

23. The multi-layered porous ceramic substrate according to claim 22, wherein, It is obtained by laminating 4 layers of the green ceramic blanks up and down, pressing them into one body, and then debinding and sintering. After sintering, one layer of the green ceramic blank forms one layer of the ceramic sheet layer. Among them, in the order of lamination from bottom to top, the weight portion of the aggregate contained in the first layer of the green ceramic blank is 40-46 parts, the average particle size of the aggregate is 70-75 μm, the weight portion of the pore former is 25-28 parts, and the average particle size of the pore former is 40-50 μm; the weight portion of the aggregate contained in the second layer of the green ceramic blank is 45-50 parts, the average particle size of the aggregate is 40-60 μm, the weight portion of the pore former is 20-25 parts, and the average particle size of the pore former is 40-50 μm; the weight portion of the aggregate contained in the third layer of the green ceramic blank is 40-46 parts, the average particle size of the aggregate is 70-75 μm, the weight portion of the pore former is 25-28 parts, and the average particle size of the pore former is 40-50 μm; the weight portion of the aggregate contained in the fourth layer of the green ceramic blank is 35-45 parts, the average particle size of the aggregate is 10-20 μm, the weight portion of the pore former is 25-30 parts, and the average particle size of the pore former is 35-40 μm.

24. The multi-layered porous ceramic matrix according to claim 8, characterized in that, There are 4 groups of the ceramic sheet layers, and each group of the ceramic sheet layers has 1 layer of the ceramic sheet layer. Among them, in the order of lamination from bottom to top, the average pore diameter of the micropores in each layer of the ceramic sheet layer has a law of alternating changes in size. The pore diameter of the micropores in the first layer of the ceramic sheet layer is 40-50 μm, the pore diameter of the micropores in the second layer of the ceramic sheet layer is 30-40 μm, the pore diameter of the micropores in the third layer of the ceramic sheet layer is 40-50 μm, and the pore diameter of the micropores in the fourth layer of the ceramic sheet layer is 10-20 μm.

25. The multi-layered porous ceramic substrate according to claim 24, characterized in that, It is obtained by laminating 4 layers of the green ceramic blanks up and down, pressing them into one body, and then debinding and sintering. After sintering, one layer of the green ceramic blank forms one layer of the ceramic sheet layer. Among them, in the order of lamination from bottom to top, the weight portion of the aggregate contained in the first layer of the green ceramic blank is 40-46 parts, the average particle size of the aggregate is 70-75 μm, the weight portion of the pore former is 25-28 parts, and the average particle size of the pore former is 40-50 μm; the weight portion of the aggregate contained in the second layer of the green ceramic blank is 45-50 parts, the average particle size of the aggregate is 40-60 μm, the weight portion of the pore former is 20-25 parts, and the average particle size of the pore former is 40-50 μm; the weight portion of the aggregate contained in the third layer of the green ceramic blank is 40-46 parts, the average particle size of the aggregate is 70-75 μm, the weight portion of the pore former is 25-28 parts, and the average particle size of the pore former is 40-50 μm; the weight portion of the aggregate contained in the fourth layer of the green ceramic blank is 35-45 parts, the average particle size of the aggregate is 10-20 μm, the weight portion of the pore former is 25-30 parts, and the average particle size of the pore former is 35-40 μm.

26. The multi-layered porous ceramic substrate according to claim 8, wherein There are 3 groups of the ceramic sheet layers, and each group of the ceramic sheet layers has 2 ceramic sheet layers, with a total of 6 sheet layers. Among them, in the order from bottom to top, the average pore diameter of the micropores in each ceramic sheet layer has a gradient change law from large to small. The pore diameter of the micropores in the first group of ceramic sheet layers is 35 - 50 um, the pore diameter of the micropores in the second group of ceramic sheet layers is 20 - 35 um, and the pore diameter of the micropores in the third group of ceramic sheet layers is 10 - 20 um.

27. The preparation method of the multi-layer porous ceramic matrix according to claim 26, wherein It is prepared by laminating 2 layers of the same ceramic green bodies up and down to form 1 group of ceramic green bodies, and then laminating and pressing 3 different groups of the ceramic green bodies up and down to form an integrated body, followed by debinding and sintering. One layer of the ceramic green body forms one layer of the ceramic sheet layer after sintering. Among them, in the order of lamination from bottom to top, the weight fraction of the aggregate contained in the first group of ceramic green bodies is 40 - 46 parts, the average particle diameter of the aggregate is 60 - 75 um, the weight fraction of the pore former is 25 - 30 parts, and the average particle diameter of the pore former is 40 - 50 um; the weight fraction of the aggregate contained in the second group of ceramic green bodies is 40 - 48 parts, the average particle diameter of the aggregate is 15 - 50 um, the weight fraction of the pore former is 25 - 30 parts, and the average particle diameter of the pore former is 35 - 40 um; the weight fraction of the aggregate contained in the third group of ceramic green bodies is 35 - 45 parts, the average particle diameter of the aggregate is 10 - 20 um, the weight fraction of the pore former is 25 - 30 parts, and the average particle diameter of the pore former is 35 - 40 um.

28. The multi-layered porous ceramic matrix according to claim 8, wherein, There are 4 groups of the ceramic sheet layers, and each group of the ceramic sheet layers has 2 ceramic sheet layers, with a total of 8 sheet layers. Among them, in the order from bottom to top, the average pore diameter of the micropores in each ceramic sheet layer has a gradient change law from large to small. The pore diameter of the micropores in the first group of ceramic sheet layers is 40 - 50 um, the pore diameter of the micropores in the second group of ceramic sheet layers is 30 - 40 um, the pore diameter of the micropores in the third group of ceramic sheet layers is 20 - 30 um, and the pore diameter of the micropores in the fourth group of ceramic sheet layers is 10 - 20 um.

29. The preparation method of the multi-layer porous ceramic matrix according to claim 28, characterized in that, It is prepared by laminating two layers of the same green ceramic bodies in an upper and lower manner to form a set of green ceramic bodies, and then pressing four different sets of the green ceramic bodies into one body, followed by debinding and sintering. After sintering, one layer of the green ceramic body forms one layer of the ceramic sheet layer. The green ceramic body is prepared by a tape casting process using a tape casting ceramic slurry. Among them, in the order of lamination from bottom to top, the weight fraction of the aggregate in the first set of green ceramic bodies is 40-46 parts, the average particle size of the aggregate is 70-75 μm, the weight fraction of the pore former is 25-28 parts, and the average particle size of the pore former is 40-50 μm; the weight fraction of the aggregate in the second set of green ceramic bodies is 45-50 parts, the average particle size of the aggregate is 40-60 μm, the weight fraction of the pore former is 20-25 parts, and the average particle size of the pore former is 40-50 μm; the weight fraction of the aggregate in the third set of green ceramic bodies is 40-48 parts, the average particle size of the aggregate is 15-30 μm, the weight fraction of the pore former is 25-30 parts, and the average particle size of the pore former is 35-40 μm; the weight fraction of the aggregate in the fourth set of green ceramic bodies is 35-45 parts, the average particle size of the aggregate is 10-20 μm, the weight fraction of the pore former is 25-30 parts, and the average particle size of the pore former is 35-40 μm.

30. A multi-layer porous ceramic atomization core, characterized in that, It includes a multi-layer porous ceramic matrix according to any one of claims 1-29. One of the upper and lower surfaces of the multi-layer porous ceramic matrix is set as the atomization surface, and the other surface is set as the liquid guiding surface. Electrode layers are respectively provided at both ends of the atomization surface. The electrode layers are prepared by screen-printing the metal slurry and then sintering. A metal heating layer is also provided on the atomization surface. The metal heating layer is prepared by a metal sputtering coating process or by a process of screen-printing another metal slurry and then sintering. The metal heating layer is electrically connected to the electrode layers.

31. The multi-layered porous ceramic atomization core according to claim 30, wherein Among the upper and lower surfaces of the multi-layer porous ceramic matrix, the surface with a smaller pore diameter of the micropores is selected as the atomization surface, and the other surface is set as the liquid guiding surface.

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