A tape-casting porous atomizing heating element and a preparation method thereof

Abstract

The present invention relates to the technical field of heating elements, and specifically to a tape-cast porous atomizing heating element and a preparation method thereof, comprising a support layer, a heating layer, an atomizing layer, a heat dissipation layer and an oil storage layer arranged in sequence from the inside to the outside; the heating layer is printed on the inner surface of the atomizing layer, the outer surface of the support layer is bonded to the inner surface of the heating layer, the heat dissipation layer and the oil storage layer are rolled on the outer circumferential surface of the atomizing layer in sequence, and the welding electrode holes are reserved for welding electrodes when the support layer is stamped. The heating element of the present invention is obtained by combining a multilayer structure, and the porosity, pore size and heat dissipation speed of each tape-cast substrate are different. After isostatic pressing, five layers of lamination with different pore sizes, different thicknesses and different heat dissipation speeds can be achieved, so that the porosity and oil conduction speed range of each layer of the heating element are adjustable, the atomization effect is good, a gradient taste can be brought, and the production efficiency is high; at the same time, the heating layer is printed on the inner surface of the atomizing layer to be isolated from the atomized smoke oil, thereby avoiding the carbon deposition problem.

Description

Technical Field

[0001] The present invention relates to the technical field of heating elements, and in particular to a tape-casting porous atomizing heating element and a preparation method thereof. Background Art

[0002] The core component of the electronic cigarette is the porous atomizing heating element, which uses the microporous structure of porous ceramics to store the e-liquid. The heating circuit is printed on the ceramic substrate by silk screen printing. When inhaling, the e-liquid stored in the micropores of the porous ceramics is atomized by heating the heating circuit to achieve the smoking effect. The porosity, strength, pore size and distribution of the porous ceramics in the atomizing core play a vital role in the atomization effect and the smoking taste.

[0003] At present, the porous atomizing heating element used in electronic cigarette atomization is mainly prepared by the process of integrally forming a metal heating wire and a porous ceramic matrix. The main methods for preparing the porous ceramic matrix are dry pressing, tape casting, hot die casting, and grouting. The main difficulties are how to accurately control the pore size, pore morphology, and pore distribution of the porous ceramic, how to increase the porosity, improve the efficiency of smoke oil atomization, and how to reduce costs. The slurry in the dry pressing, hot die casting, and grouting processes is difficult to mix evenly, and the prepared porous ceramics have poor dimensional stability, low efficiency, and unstable performance. Summary of the invention

[0004] In order to overcome the shortcomings and deficiencies in the prior art, the purpose of the present invention is to provide a cast porous atomizing heating element, which is obtained by combining a multi-layer structure. The porosity, pore size and heat dissipation rate of each layer of the cast substrate are different. After isostatic pressing, five layers of different pore sizes, different thicknesses and different heat dissipation rates can be stacked, so that the porosity and oil conduction speed range of each layer of the heating element are adjustable, the atomization effect is good, a gradient taste can be brought, and the production efficiency is high; at the same time, the heating layer is printed on the inner surface of the atomization layer to be isolated from the atomized smoke oil, thereby avoiding the problem of carbon deposition; carbon nanotubes are introduced into the atomization layer, and carbon nanotubes can effectively improve its pore size distribution, mechanical properties, and thermal conductivity, so that the atomized particles are more sufficient and the sweetness is higher. The environmentally friendly system is used in the cast system, which can effectively solve the problems of the previous organic system being harmful and the low drying efficiency of water-based batch production, and is suitable for batch and large-scale production.

[0005] The purpose of the present invention is to provide a method for preparing a tape-cast porous atomizing heating element. The process has simple operation, convenient control, high production efficiency and low production cost. During the preparation process, a tape-casting process is used to tape-cast and laminate a support layer, an atomizing layer, a heat dissipation layer and an oil storage layer, which can realize the lamination of multiple layers with different pore sizes and different thicknesses, so that the porosity and oil conduction speed range of each layer of the finally obtained heating element are adjustable, the atomization effect is good, a gradient taste can be brought, and the production efficiency is improved.

[0006] The objective of the present invention is achieved through the following technical scheme: a tape-cast porous atomizing heating element, comprising a supporting layer, a heating layer, an atomizing layer, a heat dissipation layer and an oil storage layer arranged in sequence from the inside to the outside; the heating layer is printed on the inner surface of the atomizing layer, the outer surface of the supporting layer is bonded to the inner surface of the heating layer, the heat dissipation layer and the oil storage layer are rolled on the outer circumferential surface of the atomizing layer in sequence, and welding electrode holes are reserved for welding electrodes when the supporting layer is stamped.

[0007] The heating element in the present invention is obtained by combining a multilayer structure. The porosity, pore size and heat dissipation speed of each layer of the cast substrate are different. After isostatic pressing, five layers with different pore sizes, different thicknesses and different heat dissipation speeds can be stacked, so that the porosity and oil conduction speed range of each layer of the heating element are adjustable, the atomization effect is good, and a gradient taste can be brought, and the production efficiency is high. At the same time, the heating layer is printed on the inner surface of the atomization layer to be isolated from the atomized tobacco oil, thereby avoiding the problem of carbon deposition. Carbon nanotubes are introduced into the atomization layer, and carbon nanotubes can effectively improve its pore size distribution, mechanical properties and thermal conductivity, so that the atomized particles are more sufficient and the sweetness is higher. The environmentally friendly system is used in the cast system, which can effectively solve the problems of the previous organic system being harmful and the low drying efficiency of water-based batch production, and is suitable for batch and large-scale production.

[0008] Preferably, the support layer comprises the following raw materials in parts by weight: 30-80 parts of ceramic aggregate, 2-20 parts of sintering aid, 3-10 parts of pore former, 0.5-2 parts of dispersant, 5-25 parts of adhesive, 0.1-2 parts of defoamer, 2-16 parts of plasticizer and 40-80 parts of organic solvent.

[0009] Preferably, the atomization layer comprises the following raw materials in parts by weight: 30-80 parts of ceramic aggregate, 2-20 parts of sintering aid, 2-5 parts of carbon nanotubes, 10-25 parts of pore former, 0.5-2 parts of dispersant, 5-25 parts of adhesive, 0.1-2 parts of defoamer, 2-16 parts of plasticizer and 40-80 parts of organic solvent.

[0010] Preferably, the heat dissipation layer comprises the following raw materials in parts by weight: 30-80 parts of ceramic aggregate, 2-20 parts of sintering aid, 2-5 parts of thermal conductive powder, 10-25 parts of pore former, 0.5-2 parts of dispersant, 5-25 parts of adhesive, 0.1-2 parts of defoamer, 2-16 parts of plasticizer and 40-80 parts of organic solvent.

[0011] Preferably, the oil reservoir comprises the following raw materials in parts by weight: 30-80 parts of ceramic aggregate, 2-20 parts of sintering aid, 20-40 parts of pore former, 0.5-2 parts of dispersant, 5-25 parts of adhesive, 0.1-2 parts of defoamer, 2-16 parts of plasticizer and 40-80 parts of organic solvent.

[0012] Preferably, the material of the heating layer is any one of nickel-based, iron-based, aluminum-based, and silver-scar alloy.

[0013] Preferably, the ceramic aggregates are at least one of diatomaceous earth, quartz sand, zeolite, mica powder, white carbon black, attapulgite, cordierite, wollastonite, and silica powder; and the average particle size D50 of the ceramic aggregates is ≥20 μm.

[0014] Preferably, the sintering aid is at least one of glass powder, kaolin, calcium oxide and calcium carbonate; the average particle size D50 of the sintering aid is 1-2 μm.

[0015] The added sintering aid in the present invention forms a liquid phase at high temperature, which promotes the sintering reaction, reduces the sintering temperature, and forms a new solid phase after cooling, which promotes particle rearrangement and mass transfer process, and can produce a liquid phase at a lower temperature to promote sintering.

[0016] Preferably, the adhesive is at least one of a polyvinyl butyral adhesive, a vinyl adhesive, and an acrylic adhesive.

[0017] The above-mentioned specific adhesive used in the present invention can assist in wrapping the polymer around the powder particulate material, and further in the molding process, all the powders and additives are built into a network, which is the only continuous phase in the embryonic sheet, and plays a role in improving strength, flexibility, plasticity and lamination performance.

[0018] Preferably, the plasticizer is at least one of dibutyl phthalate, dioctyl phthalate and polyethylene glycol.

[0019] The above-mentioned specific plasticizers used in the present invention can play a highly efficient plasticizing role by synergizing their respective advantages, so as not to reduce the strength of the embryo body too much, while improving the flexibility of the embryo body, improving the molding performance, and facilitating lamination and stamping.

[0020] Preferably, the pore-forming agent is at least one of polyethylene, methyl cellulose, graphite powder, starch, and walnut powder. More preferably, the pore-forming agent is a combination of polyethylene with a particle size D50: 10-20 μm, methyl cellulose with a particle size D50: 40-60 μm, and graphite powder with a particle size D50: 80-100 μm in a mass ratio of 1-2: 3-5: 2-3.

[0021] In the present invention, by using different particle sizes to add pore-forming agents to form pores, the pore size and pore structure can be adjusted, the oil conduction speed can be adjusted, and the oil conduction speed and atomization effect can be further improved, so that the prepared heating element can have a gradient taste.

[0022] Preferably, the dispersant is at least one of castor oil, glycerol, BYK-110, BYK-130, Lubrizol 20000, and Lubrizol 24000.

[0023] Preferably, the organic solvent is one or two of anhydrous ethanol, terpineol, and ethyl acetate.

[0024] Preferably, the defoaming agent is at least one of n-butanol and ethylene glycol.

[0025] Preferably, the thermally conductive powder is at least one of silicon carbide, graphite powder, silicon nitride, aluminum nitride, and aluminum oxide; the average particle size D50 of the thermally conductive powder is ≥10 μm, which can improve the thermal conductivity of the heating element.

[0026] The present invention also provides a method for preparing a tape-cast porous atomizing heating element, comprising the following steps:

[0027] S1. Mix the ceramic aggregate, sintering aid, pore former and dispersant in the supporting layer raw material with an organic solvent according to weight parts, stir at a speed of 600-1200 r / min under a vacuum degree of 5-300 Pa until uniform, and obtain a mixture for standby use;

[0028] S2, adding the adhesive, defoamer and plasticizer in the supporting layer raw material to the mixture obtained in step S1 according to parts by weight, stirring evenly to prepare a casting slurry A for the supporting layer, which is set aside;

[0029] S3, sieving the casting slurry A through a 20-500 mesh screen, heating it to 20-60° C. for degassing for 4-8 hours, and then placing the degassed casting slurry A in a casting device for casting to obtain a casting substrate A1 for standby use;

[0030] S4, according to the method of steps S1-S2, a casting slurry B for an atomizing layer, a casting slurry C for a heat dissipation layer, and a casting slurry D for an oil storage layer are prepared in sequence, and the casting slurry B, the casting slurry C, and the casting slurry D are then made into casting substrates B1, casting substrates C1, and casting substrates D1 in sequence according to the method of step S3, and are set aside;

[0031] S5, cutting and punching the cast substrate A1, cast substrate B1, cast substrate C1, and cast substrate D1, and then printing the heating layer on the inner surface of the cast substrate B1 to make cast substrate A2, cast substrate B2, cast substrate C2, and cast substrate D2 of designed size for standby use;

[0032] S6, rolling up the cast substrate A2, cast substrate B2, cast substrate C2, and cast substrate D2 obtained in step S5 in turn, isostatically pressing and laminating, to obtain a column E for standby use; the middle of the column E is supported by a support body, the temperature of the isostatic pressing and laminating is 50-80°C, the pressure is 12-30MPa, and the isostatic pressing time is 200-1000s;

[0033] S7, bury the prepared column E in corundum powder and sinter, during sintering, according to the first zone: the heating curve is 20-600℃, the heating rate is 0.5℃ / min, and the heat preservation time is 1h; the second zone: the heating curve is 600-1100℃, the heating rate is 1℃ / min, and the heat preservation time is 2h, sintering in one piece to obtain a ceramic column for standby use;

[0034] S8. Welding electrode wires to the ceramic cylinder obtained in step S7 to finally produce a porous atomizing heating element.

[0035] The porous atomizing heating element in the present invention is prepared by adopting the above method. The process is simple to operate, convenient to control, high in production efficiency and low in production cost. During the preparation process, the support layer, the atomizing layer, the heat dissipation layer and the oil storage layer are formed by tape casting. Multiple layers with different pore sizes and different thicknesses can be stacked, so that the porosity and oil conduction speed range of each layer of the heating element finally prepared are adjustable, the atomization effect is good, a gradient taste can be brought, and the production efficiency is improved. Among them, the tape casting slurry mixing method in step S1 adopts vacuum-sealed stirring to avoid solvent volatilization and does not destroy the powder particle size and microporous structure.

[0036] Preferably, the casting equipment in step S3 adopts bottom heating with a bottom temperature of 20-95°C, and the casting temperature is set in sequence according to the outflow direction of the casting substrate: 25-40°C, 40-50°C, 50-60°C, 60-70°C, 70-80°C, 85-95°C six-stage heating, the casting speed is 0.1-0.5m / min, and the knife height of the casting equipment can be adjusted according to the set substrate thickness.

[0037] Preferably, the sintering method in step S7 is vacuum sintering or nitrogen-hydrogen mixed atmosphere sintering.

[0038] The porosity of the porous atomizing heating element is adjustable in a wide range of 5-80%, compressive strength is ≥1kgf, resistance is adjustable in the range of 0.6-1.8Ω, number of stacked layers is adjustable in the range of 3-20 layers, average pore size is adjustable in the range of 5-100 microns, oil conduction speed is ≤10s, smoke oil atomization amount is ≥0.05mg / mouth, thermal conductivity is 0.1-20w / (m*k).

[0039] The beneficial effects of the present invention are as follows: the heating element of the present invention is obtained by combining a multilayer structure, and the porosity, pore size and heat dissipation speed of each layer of the cast substrate are different. After isostatic pressing, five layers with different pore sizes, different thicknesses and different heat dissipation speeds can be stacked, so that the porosity and oil conduction speed range of each layer of the heating element are adjustable, the atomization effect is good, a gradient taste can be brought, and the production efficiency is high; at the same time, the heating layer is printed on the inner surface of the atomization layer to be isolated from the atomized smoke oil, thereby avoiding the problem of carbon deposition, and introducing carbon nanotubes into the atomization layer, which can effectively improve its pore size distribution, mechanical properties and thermal conductivity, and can make the atomized particles more sufficient and sweeter. The use of an environmentally friendly system in the cast system can effectively solve the problems of the previous organic system being harmful and the low drying efficiency of water-based batch production, and is suitable for batch and large-scale production.

[0040] The preparation method of the tape-cast porous atomizing heating element of the present invention is simple to operate, convenient to control, high in production efficiency and low in production cost. During the preparation process, a tape-casting process is adopted to tape-cast and laminate a supporting layer, an atomizing layer, a heat dissipation layer and an oil storage layer, and multiple layers with different pore sizes and different thicknesses can be laminated, so that the porosity and oil conduction speed range of each layer of the finally prepared heating element are adjustable, the atomization effect is good, a gradient taste can be brought, and the production efficiency is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 is a stereogram of the present invention;

[0042] Figure 2 It is an exploded schematic diagram of the present invention.

[0043] The figures are marked as: 1-support layer, 2-heat generating layer, 3-atomizing layer, 4-heat dissipating layer and 5-oil storage layer. DETAILED DESCRIPTION

[0044] In order to facilitate the understanding of those skilled in the art, the following embodiments and attached Figure 1-2 The present invention is further described, and the contents mentioned in the implementation modes are not intended to limit the present invention.

[0045] Example 1

[0046] A tape-cast porous atomizing heating element comprises a supporting layer 1, a heating layer 2, an atomizing layer 3, a heat dissipation layer 4 and an oil storage layer 5 which are sequentially arranged from the inside to the outside; the heating layer 2 is printed on the inner surface of the atomizing layer 3, the outer surface of the supporting layer 1 is bonded to the inner surface of the heating layer 2, the heat dissipation layer 4 and the oil storage layer 5 are sequentially rolled on the outer circumferential surface of the atomizing layer 3, and welding electrode holes are reserved for welding electrodes when the supporting layer 1 is stamped.

[0047] The support layer includes the following raw materials in parts by weight: 30 parts of ceramic aggregate, 2 parts of sintering aid, 3 parts of pore former, 0.5 parts of dispersant, 5 parts of adhesive, 0.1 parts of defoamer, 2 parts of plasticizer and 40 parts of organic solvent.

[0048] The atomization layer includes the following raw materials in parts by weight: 30 parts of ceramic aggregate, 2 parts of sintering aid, 2 parts of carbon nanotubes, 10 parts of pore former, 0.5 parts of dispersant, 5 parts of adhesive, 0.1 parts of defoamer, 2 parts of plasticizer and 40 parts of organic solvent.

[0049] The heat dissipation layer has the following raw materials in parts by weight: 30 parts of ceramic aggregate, 2 parts of sintering aid, 2 parts of thermal conductive powder, 10 parts of pore former, 0.5 parts of dispersant, 5 parts of adhesive, 0.1 parts of defoamer, 2 parts of plasticizer and 40 parts of organic solvent.

[0050] The oil reservoir layer comprises the following raw materials in parts by weight: 30 parts of ceramic aggregate, 2 parts of sintering aid, 20 parts of pore former, 0.5 parts of dispersant, 5 parts of adhesive, 0.1 parts of defoamer, 2 parts of plasticizer and 40 parts of organic solvent.

[0051] The material of the heating layer is nickel-based.

[0052] The ceramic aggregates are all diatomaceous earth; the average particle size D50 of the ceramic aggregates is 20 μm.

[0053] The sintering aid is glass powder; the average particle size D50 of the sintering aid is 1 μm.

[0054] The adhesive is a polyvinyl butyral adhesive. The plasticizer is dibutyl phthalate.

[0055] The pore-forming agent is composed of polyethylene with a particle size of D50:10 μm, methyl cellulose with a particle size of D50:40 μm, and graphite powder with a particle size of D50:80 μm in a mass ratio of 1:3:2.

[0056] The dispersant is castor oil, the organic solvent is anhydrous ethanol, and the defoamer is n-butanol.

[0057] The thermally conductive powder is silicon carbide; the average particle size D50 of the thermally conductive powder is 10 μm.

[0058] The tape-casting porous atomizing heating element is prepared by the following steps:

[0059] S1. According to parts by weight, the ceramic aggregate, sintering aid, pore former and dispersant in the supporting layer raw material are mixed with an organic solvent, and stirred at a speed of 600 r / min under a vacuum degree of 5 Pa until uniform to obtain a mixture for standby use;

[0060] S2, adding the adhesive, defoamer and plasticizer in the supporting layer raw material to the mixture obtained in step S1 according to parts by weight, stirring evenly to prepare a casting slurry A for the supporting layer, which is set aside;

[0061] S3, sieving the casting slurry A through a 20-mesh screen, heating it to 20° C. for degassing for 8 hours, and then placing the degassed casting slurry A in a casting device for casting to obtain a casting substrate A1 for standby use;

[0062] S4, according to the method of steps S1-S2, a casting slurry B for an atomizing layer, a casting slurry C for a heat dissipation layer, and a casting slurry D for an oil storage layer are prepared in sequence, and the casting slurry B, the casting slurry C, and the casting slurry D are then made into casting substrates B1, casting substrates C1, and casting substrates D1 in sequence according to the method of step S3, and are set aside;

[0063] S5, cutting and punching the cast substrate A1, cast substrate B1, cast substrate C1, and cast substrate D1, and then printing the heating layer on the inner surface of the cast substrate B1 to make cast substrate A2, cast substrate B2, cast substrate C2, and cast substrate D2 of designed size for standby use;

[0064] S6, rolling up the cast substrate A2, cast substrate B2, cast substrate C2, and cast substrate D2 obtained in step S5 in turn, isostatically pressing and laminating them to obtain a column E for standby use; the middle of the column E is supported by a support body, the temperature of the isostatic pressing and laminating is 50° C., the pressure is 12 MPa, and the isostatic pressing time is 1000 s;

[0065] S7, bury the prepared column E in corundum powder and sinter, during sintering, according to the first zone: the heating curve is 20-600℃, the heating rate is 0.5℃ / min, and the heat preservation time is 1h; the second zone: the heating curve is 600-1100℃, the heating rate is 1℃ / min, and the heat preservation time is 2h, sintering in one piece to obtain a ceramic column for standby use;

[0066] S8. Welding electrode wires to the ceramic cylinder obtained in step S7 to finally produce a porous atomizing heating element.

[0067] Among them, the casting equipment in step S3 adopts bottom heating with a bottom temperature of 20-95°C, and the casting temperature is set in sequence according to the outflow direction of the casting substrate: 25°C, 40°C, 50°C, 60°C, 70°C, 95°C six-stage heating, the casting speed is 0.1m / min, and the knife height of the casting equipment can be adjusted according to the set substrate thickness.

[0068] The sintering method in step S7 is vacuum sintering or nitrogen-hydrogen mixed atmosphere sintering.

[0069] Example 2

[0070] A tape-cast porous atomizing heating element comprises a supporting layer 1, a heating layer 2, an atomizing layer 3, a heat dissipation layer 4 and an oil storage layer 5 which are sequentially arranged from the inside to the outside; the heating layer 2 is printed on the inner surface of the atomizing layer 3, the outer surface of the supporting layer 1 is bonded to the inner surface of the heating layer 2, the heat dissipation layer 4 and the oil storage layer 5 are sequentially rolled on the outer circumferential surface of the atomizing layer 3, and welding electrode holes are reserved for welding electrodes when the supporting layer 1 is stamped.

[0071] The support layer includes the following raw materials in parts by weight: 50 parts of ceramic aggregate, 11 parts of sintering aid, 6 parts of pore former, 1 part of dispersant, 15 parts of adhesive, 1 part of defoamer, 9 parts of plasticizer and 60 parts of organic solvent.

[0072] The atomization layer includes the following raw materials in parts by weight: 50 parts of ceramic aggregate, 11 parts of sintering aid, 3 parts of carbon nanotubes, 17 parts of pore former, 1 part of dispersant, 15 parts of adhesive, 1 part of defoamer, 11 parts of plasticizer and 60 parts of organic solvent.

[0073] The heat dissipation layer has the following raw materials in parts by weight: 50 parts of ceramic aggregate, 11 parts of sintering aid, 3 parts of thermal conductive powder, 17 parts of pore former, 1 part of dispersant, 15 parts of adhesive, 1 part of defoamer, 11 parts of plasticizer and 60 parts of organic solvent.

[0074] The oil reservoir comprises the following raw materials in parts by weight: 50 parts of ceramic aggregate, 11 parts of sintering aid, 30 parts of pore former, 1 part of dispersant, 15 parts of adhesive, 1 part of defoamer, 11 parts of plasticizer and 60 parts of organic solvent.

[0075] The material of the heating layer is silver scar alloy.

[0076] The ceramic aggregates are composed of diatomaceous earth, quartz sand and silicon powder in a weight ratio of 0.8:0.7:0.6; the average particle size D50 of the ceramic aggregate is 25 μm.

[0077] The sintering aids are composed of glass powder, kaolin and calcium oxide in a weight ratio of 0.8:0.7:0.9; the average particle size D50 of the sintering aids is 1.5 μm.

[0078] The adhesive is a vinyl adhesive.

[0079] The plasticizer is composed of dibutyl phthalate, dioctyl phthalate and polyethylene glycol in a weight ratio of 0.7:0.8:0.9.

[0080] The pore-forming agent is composed of polyethylene with a particle size of D50:15 μm, methyl cellulose with a particle size of D50:50 μm, and graphite powder with a particle size of D50:90 μm in a mass ratio of 1.5:4:2.5.

[0081] The dispersant is BYK-110.

[0082] The organic solvent is composed of anhydrous ethanol, terpineol and ethyl acetate in a weight ratio of 0.9:0.4:0.7.

[0083] The defoamer is composed of n-butanol and ethylene glycol in a weight ratio of 0.8:0.7.

[0084] The thermally conductive powder is composed of silicon carbide, graphite powder and aluminum oxide in a weight ratio of 0.9:0.7:0.4; the average particle size D50 of the thermally conductive powder is 15 μm.

[0085] The tape-casting porous atomizing heating element is prepared by the following steps:

[0086] S1. Mix the ceramic aggregate, sintering aid, pore former and dispersant in the supporting layer raw material with an organic solvent according to parts by weight, stir at a speed of 800 r / min under a vacuum degree of 150 Pa until uniform, and obtain a mixture for standby use;

[0087] S2, adding the adhesive, defoamer and plasticizer in the supporting layer raw material to the mixture obtained in step S1 according to parts by weight, stirring evenly to prepare a casting slurry A for the supporting layer, which is set aside;

[0088] S3, sieving the casting slurry A through a 250-mesh screen, heating it to 40° C. for degassing for 6 hours, and then placing the degassed casting slurry A in a casting device for casting to obtain a casting substrate A1 for standby use;

[0089] S4, according to the method of steps S1-S2, a casting slurry B for an atomizing layer, a casting slurry C for a heat dissipation layer, and a casting slurry D for an oil storage layer are prepared in sequence, and the casting slurry B, the casting slurry C, and the casting slurry D are then made into casting substrates B1, casting substrates C1, and casting substrates D1 in sequence according to the method of step S3, and are set aside;

[0090] S5, cutting and punching the cast substrate A1, cast substrate B1, cast substrate C1, and cast substrate D1, and then printing the heating layer on the inner surface of the cast substrate B1 to make cast substrate A2, cast substrate B2, cast substrate C2, and cast substrate D2 of designed size for standby use;

[0091] S6, rolling up the cast substrate A2, cast substrate B2, cast substrate C2, and cast substrate D2 obtained in step S5 in turn, isostatically pressing and laminating them to obtain a column E for standby use; the middle of the column E is supported by a support body, the temperature of the isostatic lamination is 70° C., the pressure is 25 MPa, and the isostatic pressing time is 800 s;

[0092] S7, bury the prepared column E in corundum powder and sinter, during sintering, according to the first zone: the heating curve is 20-600℃, the heating rate is 0.5℃ / min, and the heat preservation time is 1h; the second zone: the heating curve is 600-1100℃, the heating rate is 1℃ / min, and the heat preservation time is 2h, sintering in one piece to obtain a ceramic column for standby use;

[0093] S8. Welding electrode wires to the ceramic cylinder obtained in step S7 to finally produce a porous atomizing heating element.

[0094] Among them, the casting equipment in step S3 adopts bottom heating with a bottom temperature of 20-90°C, and the casting temperature is set in sequence according to the outflow direction of the casting substrate: 35°C, 45°C, 55°C, 65°C, 75°C, 90°C six-stage heating, the casting speed is 0.3m / min, and the knife height of the casting equipment can be adjusted according to the set substrate thickness.

[0095] The sintering method in step S7 is vacuum sintering or nitrogen-hydrogen mixed atmosphere sintering.

[0096] Example 3

[0097] A tape-cast porous atomizing heating element comprises a supporting layer 1, a heating layer 2, an atomizing layer 3, a heat dissipation layer 4 and an oil storage layer 5 which are sequentially arranged from the inside to the outside; the heating layer 2 is printed on the inner surface of the atomizing layer 3, the outer surface of the supporting layer 1 is bonded to the inner surface of the heating layer 2, the heat dissipation layer 4 and the oil storage layer 5 are sequentially rolled on the outer circumferential surface of the atomizing layer 3, and welding electrode holes are reserved for welding electrodes when the supporting layer 1 is stamped.

[0098] The support layer includes the following raw materials in parts by weight: 80 parts of ceramic aggregate, 20 parts of sintering aid, 10 parts of pore former, 2 parts of dispersant, 25 parts of adhesive, 2 parts of defoamer, 16 parts of plasticizer and 80 parts of organic solvent.

[0099] The atomization layer includes the following raw materials in parts by weight: 80 parts of ceramic aggregate, 20 parts of sintering aid, 5 parts of carbon nanotubes, 25 parts of pore former, 2 parts of dispersant, 25 parts of adhesive, 2 parts of defoamer, 16 parts of plasticizer and 80 parts of organic solvent.

[0100] The heat dissipation layer comprises the following raw materials in parts by weight: 80 parts of ceramic aggregate, 20 parts of sintering aid, 5 parts of thermal conductive powder, 25 parts of pore former, 2 parts of dispersant, 25 parts of adhesive, 2 parts of defoamer, 16 parts of plasticizer and 80 parts of organic solvent.

[0101] The oil reservoir layer comprises the following raw materials in parts by weight: 80 parts of ceramic aggregate, 20 parts of sintering aid, 40 parts of pore former, 2 parts of dispersant, 25 parts of adhesive, 2 parts of defoamer, 16 parts of plasticizer and 80 parts of organic solvent.

[0102] The material of the heating layer is aluminum-based.

[0103] The ceramic aggregates are all cordierite; the average particle size D50 of the ceramic aggregates is 30 μm.

[0104] The sintering aid is glass powder; the average particle size D50 of the sintering aid is 2 μm.

[0105] The adhesive is an acrylic adhesive.

[0106] The plasticizer is dioctyl phthalate.

[0107] The pore-forming agent is composed of polyethylene with a particle size of D50: 20 μm, methyl cellulose with a particle size of D50: 60 μm, and graphite powder with a particle size of D50: 100 μm in a mass ratio of 2:5:3.

[0108] The dispersant is Lubrizol 20000. The organic solvent is anhydrous ethanol. The defoaming agent is n-butanol.

[0109] The thermally conductive powder is aluminum oxide; the average particle size D50 of the thermally conductive powder is 30 μm.

[0110] The tape-casting porous atomizing heating element is prepared by the following steps:

[0111] S1. According to parts by weight, the ceramic aggregate, sintering aid, pore former and dispersant in the supporting layer raw material are mixed with an organic solvent, and stirred at a speed of 1200 r / min under a vacuum degree of 300 Pa until uniform to obtain a mixture for standby use;

[0112] S2, adding the adhesive, defoamer and plasticizer in the supporting layer raw material to the mixture obtained in step S1 according to parts by weight, stirring evenly to prepare a casting slurry A for the supporting layer, which is set aside;

[0113] S3, sieving the casting slurry A through a 500-mesh screen, heating it to 60° C. for degassing for 4 hours, and then placing the degassed casting slurry A in a casting device for casting to obtain a casting substrate A1 for standby use;

[0114] S4, according to the method of steps S1-S2, a casting slurry B for an atomizing layer, a casting slurry C for a heat dissipation layer, and a casting slurry D for an oil storage layer are prepared in sequence, and the casting slurry B, the casting slurry C, and the casting slurry D are then made into casting substrates B1, casting substrates C1, and casting substrates D1 in sequence according to the method of step S3, and are set aside;

[0115] S5, cutting and punching the cast substrate A1, cast substrate B1, cast substrate C1, and cast substrate D1, and then printing the heating layer on the inner surface of the cast substrate B1 to make cast substrate A2, cast substrate B2, cast substrate C2, and cast substrate D2 of designed size for standby use;

[0116] S6, rolling up the cast substrate A2, cast substrate B2, cast substrate C2, and cast substrate D2 obtained in step S5 in turn, isostatically pressing and laminating them to obtain a column E for standby use; the middle of the column E is supported by a support body, the temperature of the isostatic lamination is 80° C., the pressure is 30 MPa, and the isostatic pressing time is 200 s;

[0117] S7, bury the prepared column E in corundum powder and sinter, during sintering, according to the first zone: the heating curve is 20-600℃, the heating rate is 0.5℃ / min, and the heat preservation time is 1h; the second zone: the heating curve is 600-1100℃, the heating rate is 1℃ / min, and the heat preservation time is 2h, sintering in one piece to obtain a ceramic column for standby use;

[0118] S8. Welding electrode wires to the ceramic cylinder obtained in step S7 to finally produce a porous atomizing heating element.

[0119] Among them, the casting equipment in step S3 adopts bottom heating with a bottom temperature of 20-95°C, and the casting temperature is set in sequence according to the outflow direction of the casting substrate: 40°C, 50°C, 60°C, 70°C, 80°C, 95°C six-stage heating, the casting speed is 0.1-0.5m / min, and the knife height of the casting equipment can be adjusted according to the set substrate thickness.

[0120] The sintering method in step S7 is vacuum sintering or nitrogen-hydrogen mixed atmosphere sintering.

[0121] Comparative Example 1

[0122] The difference between this comparative example and the above-mentioned embodiment 2 is that no carbon nanotubes are added to the raw materials of the atomization layer of this comparative example. The rest of the contents of this comparative example are the same as those of embodiment 2, and will not be repeated here.

[0123] Comparative Example 2

[0124] The difference between this comparative example and the above-mentioned embodiment 2 is that no sintering aid and thermal conductive powder are added to the raw materials of the heat dissipation layer of this comparative example. The rest of the contents of this comparative example are the same as those of embodiment 2 and will not be repeated here.

[0125] Comparative Example 3

[0126] The difference between this comparative example and the above-mentioned embodiment 2 is that no heat dissipation layer is provided in this comparative example. The rest of the contents of this comparative example are the same as those of embodiment 2, and will not be repeated here.

[0127] The performance of the porous atomizing heating element obtained in Example 2 and Comparative Examples 1-3 was tested, and the results are shown in Table 1:

[0128] Porosity: tested according to Auto Pore IV 9500 (Micromeritics Instrument Corporation);

[0129] Bending strength: According to GBT6569-1986-Test method for bending strength of engineering ceramics, the sample is pressurized at a speed of 5N / s and a span of 5.2mm, and the maximum load at fracture is tested in N;

[0130] Oil conduction speed: Take a 9mm*9mm*2mm sample, drop 0.1ml of e-liquid at a height of 10mm from the sample, the e-liquid is a mixture of propylene glycol and glycerol in a volume ratio of 1:1, and record the time from the e-liquid contacting the sample to the complete penetration of the sample, in seconds;

[0131] Thermal conductivity: Tested in accordance with (GB / T 5990-2006);

[0132] Resistance: Use a resistance tester to clamp both ends of the electrode wire for testing. The test equipment is a conventional resistance tester sold on the market, and there are no special requirements;

[0133] Average pore size: tested in accordance with GB / T32361-20115;

[0134] Atomization volume: -1.0kPa pressure, constant for 3s is defined as 1 puff test.

[0135] Table 1

[0136]

[0137] It can be seen from the above test data that the porous atomizing heating element of the present invention has good porosity, bending strength, oil conductivity, thermal conductivity, good atomization effect, large amount of smoke, and can bring a gradient taste; adding carbon nanotubes to the atomization layer can effectively improve its mechanical properties, thermal conductivity and oil conduction speed, and adding sintering aids and thermal conductive powders to the heat dissipation layer can further improve the mechanical properties and thermal conductivity of the heat dissipation layer.

[0138] The above embodiments are preferred implementation schemes of the present invention. In addition, the present invention may also be implemented in other ways. Any obvious replacement without departing from the concept of the present invention is within the protection scope of the present invention.

Claims

1. A tape-cast porous atomizing heating element, characterized in that: The invention comprises a support layer, a heating layer, an atomization layer, a heat dissipation layer and an oil storage layer which are arranged in sequence from the inside to the outside; the porosity, pore size and heat dissipation speed of each layer of the tape-cast substrate are different, and five layers of tape-cast substrates are rolled up and isostatically pressed in sequence to achieve five layers of lamination with different pore sizes, different thicknesses and different heat dissipation speeds, the heating layer is printed on the inner surface of the atomization layer, the outer surface of the support layer is bonded to the inner surface of the heating layer, the heat dissipation layer and the oil storage layer are rolled up on the outer circumference of the atomization layer in sequence, and the welding electrode holes are reserved when the support layer is stamped. The supporting layer comprises the following raw materials in parts by weight: 30-80 parts of ceramic aggregate, 2-20 parts of sintering aid, 3-10 parts of pore former, 0.5-2 parts of dispersant, 5-25 parts of adhesive, 0.1-2 parts of defoamer, 2-16 parts of plasticizer and 40-80 parts of organic solvent; the atomizing layer comprises the following raw materials in parts by weight: 30-80 parts of ceramic aggregate, 2-20 parts of sintering aid, 2-5 parts of carbon nanotube, 10-25 parts of pore former, 0.5-2 parts of dispersant, 5-25 parts of adhesive, defoamer 0.1-2 parts, plasticizer 2-16 parts and organic solvent 40-80 parts; the heat dissipation layer comprises the following raw materials in parts by weight: ceramic aggregate 30-80 parts, sintering aid 2-20 parts, thermal conductive powder 2-5 parts, pore-forming agent 10-25 parts, dispersant 0.5-2 parts, adhesive 5-25 parts, defoamer 0.1-2 parts, plasticizer 2-16 parts and organic solvent 40-80 parts; the heat dissipation layer comprises the following raw materials in parts by weight: ceramic aggregate 30-80 parts, sintering aid 2-20 parts, thermal conductive powder 2-5 parts, pore-forming agent 10 -25 parts, dispersant 0.5-2 parts, adhesive 5-25 parts, defoamer 0.1-2 parts, plasticizer 2-16 parts and organic solvent 40-80 parts; the oil reservoir layer has the following raw materials in parts by weight: ceramic aggregate 30-80 parts, sintering aid 2-20 parts, pore-forming agent 20-40 parts, dispersant 0.5-2 parts, adhesive 5-25 parts, defoamer 0.1-2 parts, plasticizer 2-16 parts and organic solvent 40-80 parts; the material of the heating layer is any one of nickel-based, iron-based, aluminum-based and silver-scar alloy.

2. The tape-cast porous atomizing heating element according to claim 1, characterized in that: The ceramic aggregates are at least one of diatomaceous earth, quartz sand, zeolite, mica powder, white carbon black, attapulgite, cordierite, wollastonite, and silica powder; the sintering aid is at least one of glass powder, kaolin, calcium oxide, and calcium carbonate; the adhesive is at least one of polyvinyl butyral adhesive, vinyl adhesive, and acrylic adhesive; the plasticizer is at least one of dibutyl phthalate, dioctyl phthalate, and polyethylene glycol.

3. The tape-cast porous atomizing heating element according to claim 1, characterized in that: The pore-forming agent is at least one of polyethylene, methyl cellulose, graphite powder, starch, and walnut powder; the dispersant is at least one of castor oil, glycerol, BYK-110, BYK-130, Lubrizol 20000, and Lubrizol 24000; the organic solvent is one or two of anhydrous ethanol, pine alcohol, and ethyl acetate; and the defoaming agent is at least one of n-butanol and ethylene glycol.

4. The tape-cast porous atomizing heating element according to claim 1, characterized in that: The thermally conductive powder is at least one of silicon carbide, graphite powder, silicon nitride, aluminum nitride, and aluminum oxide.

5. A method for preparing a tape-cast porous atomizing heating element according to any one of claims 1 to 4, characterized in that: The steps include: S1. Mix the ceramic aggregate, sintering aid, pore former and dispersant in the supporting layer raw material with an organic solvent according to weight parts, stir at a speed of 600-1200 r / min under a vacuum degree of 5-300 Pa until uniform, and obtain a mixture for standby use; S2, adding the adhesive, defoamer and plasticizer in the supporting layer raw material to the mixture obtained in step S1 according to parts by weight, stirring evenly to prepare a casting slurry A for the supporting layer, which is set aside; S3, sieving the casting slurry A through a 20-500 mesh screen, heating it to 20-60° C. for degassing for 4-8 hours, and then placing the degassed casting slurry A in a casting device for casting to obtain a casting substrate A1 for standby use; S4, according to the method of steps S1-S2, a casting slurry B for an atomizing layer, a casting slurry C for a heat dissipation layer, and a casting slurry D for an oil storage layer are prepared in sequence, and the casting slurry B, the casting slurry C, and the casting slurry D are then made into casting substrates B1, casting substrates C1, and casting substrates D1 in sequence according to the method of step S3, and are set aside; S5, cutting and punching the cast substrate A1, cast substrate B1, cast substrate C1, and cast substrate D1, and then printing the heating layer on the inner surface of the cast substrate B1 to make cast substrate A2, cast substrate B2, cast substrate C2, and cast substrate D2 of designed size for standby use; S6, rolling up the cast substrate A2, cast substrate B2, cast substrate C2, and cast substrate D2 obtained in step S5 in turn, isostatically pressing and laminating, to obtain a column E for standby use; the middle of the column E is supported by a support body, the temperature of the isostatic pressing and laminating is 50-80°C, the pressure is 12-30MPa, and the isostatic pressing time is 200-1000s; S7, bury the prepared column E in corundum powder and sinter, during sintering, according to the first zone: the heating curve is 20-600℃, the heating rate is 0.5℃ / min, and the heat preservation time is 1h; the second zone: the heating curve is 600-1100℃, the heating rate is 1℃ / min, and the heat preservation time is 2h, sintering in one piece to obtain a ceramic column for standby use; S8. Welding electrode wires to the ceramic cylinder obtained in step S7 to finally produce a porous atomizing heating element.

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