Modified 3D printed ceramic atomizing core substrate and preparation method thereof

Abstract

The application provides a modified 3D printing ceramic atomization core base body and a preparation method thereof, and belongs to the technical field of electronic cigarettes. The 3D printing ceramic framework is prepared by 3D printing, and the ceramic framework is modified by a porous slurry. The modification method is a method of dipping the porous slurry. After dipping, the porous ceramic atomization core base body is obtained by sintering. The 3D printing ceramic framework has strong designability of pore structure and overall structure, good structural consistency, high product consistency, an easy-to-verify scheme, and high efficiency. The porous modification slurry preparation method is simple and convenient to use. The dipping process is simple, has strong realizability, good consistency, low cost, and large output. The pores formed by 3D printing are large, the pores formed by dipping are small, the large and small pores cooperate with each other, the tobacco tar can be better guided and stored, and the comprehensive performance of the ceramic atomization core is improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of electronic cigarettes, and particularly relates to a modified 3D-printed ceramic atomization core base and a preparation method thereof. BACKGROUND

[0002] An electronic cigarette is an electronic product that simulates a cigarette and has the same appearance, smoke, taste and feeling as a cigarette. It is a product that allows users to inhale nicotine and the like after converting them into steam through atomization and the like. Compared with a real cigarette, the electronic cigarette does not have harmful substances such as tar and suspended particles in the cigarette, and has a relatively small impact on human health. Electronic cigarette atomization is mainly performed by an electronic cigarette atomization core, which mainly adopts metal wire heating atomization or ceramic atomization core atomization.

[0003] At present, the ceramic atomization core base of the electronic cigarette is mainly prepared by hot-pressing and then sintering, and the skeleton thereof is mainly connected by mutual sintering and bonding between ceramic particles and a low-temperature glass phase, and the design and formation of internal pores are mainly achieved by introducing a pore-forming agent. However, the above method is prone to problems such as a wide pore size range, uneven pore distribution, a large deviation between an actual product and a design, and poor consistency of the ceramic base in terms of pore size and porosity, thereby affecting the product consistency of the ceramic atomization core.

[0004] 3D printing is a rapid prototyping technology, also known as additive manufacturing. It is based on a digital model file and uses powder-like metal or plastic and other materials that can be bonded to construct an object through layer-by-layer printing. 3D-printed porous ceramics have the advantages of structural designability, high precision, high efficiency, wide applicability and personalization, and are widely used in catalyst carriers, filters, sound and light heat and many other fields. The introduction of the 3D printing technology into the ceramic atomization core can improve the product consistency of the ceramic atomization core and the consistency of the ceramic base in terms of pore size and porosity, thereby improving the performance of the ceramic atomization core. However, the pore size of the 3D printing is too large, and the ceramic atomization core has the problem of oil leakage. In addition, due to the single pore size, although the oil infiltration and oil guiding performance is good, the oil storage performance is poor, which is not conducive to continuous atomization of the tobacco tar.

[0005] Therefore, the application adopts 3D printing to prepare a porous ceramic skeleton, and then modifies the ceramic skeleton by using a porous slurry. The modification method is to dip the porous slurry, and then sinter to obtain a porous ceramic atomization core base. The 3D-printed ceramic skeleton has strong designability, good structural consistency and high product consistency. The porous modification slurry has a simple preparation method and is easy to use. The dipping process is simple, has strong realizability, good consistency, low cost and large output. The pores formed by 3D printing are large, and the pores formed by dipping are small. The large and small pores cooperate with each other to better guide and store the tobacco tar, thereby improving the comprehensive performance of the ceramic atomization core. SUMMARY

[0006] In order to solve the problem of too large pore diameter of simple 3D printing, the ceramic atomization core exists the problem of oil leakage, in addition, due to the single pore diameter, although the oil infiltration and oil guiding performance is good, the oil storage performance is poor, which is not conducive to continuous atomization of tobacco tar, the present application adopts 3D printing to prepare a porous ceramic skeleton, and then the porous ceramic skeleton is modified by a porous slurry, the modification method is that the porous slurry is dipped, and the porous ceramic atomization core matrix is obtained after dipping and sintering. The 3D printed ceramic skeleton has strong designability, good structural consistency and high product consistency; the porous modification slurry has simple preparation method and convenient use; the dipping process has strong realizability, good consistency, low cost and large output; the large pores formed by 3D printing and the small pores formed by dipping are matched with each other, so that the tobacco tar can be better guided and stored, and the comprehensive performance of the ceramic atomization core is improved.

[0007] The first aspect of the present application provides a preparation method of a modified 3D printed ceramic atomization core matrix, which comprises the following steps:

[0008] S1, configuring a 3D printing ceramic slurry to prepare a porous ceramic precursor voxel by 3D printing; and then performing glue removal treatment;

[0009] S2, sintering the porous ceramic precursor voxel obtained after the treatment in step S1 to obtain a 3D printed porous ceramic matrix;

[0010] S3, configuring a dipping modification slurry;

[0011] S4, dipping the porous ceramic precursor voxel after the treatment in step S1 or the 3D printed porous ceramic matrix obtained after the treatment in step S2 into the dipping modification slurry in step S3, taking out and drying after dipping for a period of time to obtain a modified 3D printed ceramic atomization core matrix precursor;

[0012] S5, sintering the modified 3D printed ceramic atomization core matrix precursor obtained in S4 to obtain a modified 3D printed ceramic atomization core matrix.

[0013] Further, the 3D printing ceramic slurry comprises a ceramic material, and the ceramic material is one or more of alumina, zirconia, silica and ZTA. The ceramic material used is a general material, and further preferably, in order to further improve the stability of the 3D printed porous ceramic atomization core, ceramic materials with different particle sizes can be selected for gradation.

[0014] Further, the ceramic slurry further comprises a binder and a solvent, and the weight ratio of the ceramic material, the binder and the solvent in the ceramic slurry is 70-90:2-5:10-30. The binder used can be one or more of polyurethane, epoxy resin, acrylate, epoxy acrylate or ethyl cellulose, and the solvent used can be one or more of ethanol, propanol, butanol and the like. Further preferably, the weight ratio of the ceramic material, the binder and the solvent in the ceramic slurry is 70-80:2-4:15-25, and further, the weight ratio is 75-80:3:20-25, and further, 75:3:22.

[0015] Further, the ceramic material is selected as Al2O3 powder with D50 of 10-20 μm, Al2O3 powder with D50 of 4-8 μm, the mass ratio of Al2O3 powder with D50 of 10-20 μm and Al2O3 powder with D50 of 4-8 μm is between 5:1 and 1:5, and further, can be 50-60:15-25; further, the ceramic material is selected as Al2O3 powder with D50 of 15-20 μm and Al2O3 powder with D50 of 5-8 μm; and further, the weight ratio of Al2O3 powder with D50 of 15-20 μm and Al2O3 powder with D50 of 5-8 μm is 55:20.

[0016] Further, the 3D-printed porous ceramic precursor voxel specifically has an external size of 9*4.5*3.5 mm, an internal cavity of 7*3*2 mm, a pore size and a pore spacing of 100 μm, and is uniformly distributed on the overall matrix, and is a cuboid containing a cavity. Further, the specific method of the 3D-printed porous ceramic precursor voxel can also be a general printing method and a general size.

[0017] Further, the dipping slurry comprises a ceramic material, a binder and a solvent, and the weight ratio of the ceramic material, the binder and the solvent is 70-90:1-5:10-30, and the ceramic material is one or more of alumina, zirconia, silica, silicon nitride or ZTA, and further, different particle sizes of the ceramic material can be graded, and different particle sizes and different types of the ceramic material can be graded to improve the adhesion of the dipping slurry and the ceramic substrate precursor.

[0018] Further, the ceramic material in the dipping slurry is Al2O3 powder with a D50 of 15-25 μm, Al2O3 powder with a D50 of 4-8 μm, and SiO2 powder with a D50 of 15-25 μm, and the weight ratio is 40-50:10-20:10-20, further, the ceramic material in the dipping slurry is Al2O3 powder with a D50 of 20-25 μm, Al2O3 powder with a D50 of 5-6 μm, and SiO2 powder with a D50 of 20-25 μm, and the weight ratio is 45-50:15-20:10-15, and the above weight ratio is further 45:15:15.

[0019] Further, the degassing treatment step in the step S1 is programmed temperature rising to 400-500℃ at a temperature rising rate of 0.1℃ / min-10℃ / min, and then continued to rise to 600-700℃ at a temperature rising rate of 1℃ / min-10℃ / min, and the holding time is 40-80 minutes.

[0020] Further, the sintering treatment step in the step S2 is programmed temperature rising to 1300-1500℃ at a temperature rising rate of 1℃ / min-10℃ / min, and the holding time is 3-6h.

[0021] Further, the dipping time in the step S4 is 5-30s, and further 10-20s; further, the modified 3D printing ceramic atomization core substrate precursor after the dipping slurry dipping treatment is further dried.

[0022] Further, the sintering treatment step in the step S5 is programmed temperature rising to 300-500℃ after drying, and the holding time is 1-5h, then programmed temperature rising to 800-1500℃ at a temperature rising rate of 1℃ / min-10℃ / min, and the holding time is 1-6h. Further, the holding time is 1-5h at 300-500℃, and then sintering at 800-1200℃ for 1-5h.

[0023] Further, the porous ceramic substrate obtained by the above steps contains large and small pore structures, the large pores are obtained by 3D printing, and the pore size and pore spacing are 100 μm, and the small pores are obtained by sintering the modified slurry and adhering to the skeleton of the large pores, and the pore size is 20-50 μm, and the pore spacing is 20-100 μm, and the distribution is relatively uniform.

[0024] The second aspect of this invention provides a modified 3D-printed ceramic atomizing core substrate. This modified 3D-printed ceramic atomizing core substrate is prepared using the aforementioned method. The resulting modified 3D-printed ceramic atomizing core substrate has a porous structure, comprising both large and small pore structures. The large pores have a diameter and spacing of 100 μm, while the small pores have a diameter between 20-50 μm and a spacing between 20-100 μm, with a relatively uniform distribution. When e-liquid for e-cigarette atomization is dripped into the cavity of the porous ceramic substrate, the e-liquid can penetrate the porous ceramic substrate relatively quickly without dripping out of the cavity. This indicates that after modification, the porous ceramic substrate simultaneously possesses the functions of guiding and locking in e-liquid, thus meeting the requirements for e-cigarette atomization.

[0025] The beneficial effects of this invention are as follows:

[0026] This invention provides a method for preparing a porous ceramic skeleton using 3D printing, followed by modification of the ceramic skeleton with a porous slurry. The modification method involves dipping the ceramic skeleton into the porous slurry, followed by sintering to obtain a porous ceramic atomizing core substrate. The 3D-printed ceramic skeleton offers high design flexibility, good structural consistency, and high product consistency. The porous modification slurry preparation method is simple and convenient to use. The dipping process is simple, highly feasible, consistent, low-cost, and allows for high yield. The pores formed by 3D printing are large, while those formed by dipping are small; the combination of large and small pores allows for better e-liquid extraction and storage, improving the overall performance of the ceramic atomizing core.

[0027] The porous ceramic matrix provided by this invention includes two types of pore structures: large pores and small pores. The large pores are obtained by 3D printing, with a pore diameter and pore spacing of 100 μm. The small pores are obtained by attaching the modified slurry to the skeleton of the large pores after sintering, with a pore diameter between 20-50 μm and a pore spacing between 20-100 μm, and the distribution is relatively uniform.

[0028] The porous ceramic matrix provided by this invention allows e-liquid for e-cigarette atomization to be dripped into its cavity. The e-liquid can penetrate the porous ceramic matrix relatively quickly without dripping out of the cavity. After modification, the porous ceramic matrix simultaneously possesses the functions of guiding and locking in e-liquid, meeting the requirements for e-cigarette atomization. The preparation method provided by this invention adjusts the composition and ratio of the dipping slurry, especially the particle size of the ceramic material, thereby adjusting the size of the formed pores. By adjusting the ratio of 3D printing material to dipping slurry, pore sizes within 100 μm can be obtained. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments.

[0030] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. It should be understood that the following description is merely illustrative and is not intended to limit the invention.

[0031] The terms “comprising,” “including,” “having,” “containing,” or any other variations thereof, as used herein, are intended to cover a non-exclusive inclusion. A composition, step, method, article, or apparatus that includes the listed elements is not necessarily limited to those elements, but may include other elements not expressly listed or elements inherent to such composition, step, method, article, or apparatus.

[0032] The phrase "composed of..." excludes any unspecified elements, steps, or components. If used in a claim, this phrase makes the claim closed, excluding materials other than those described, except for conventional impurities associated with them. When the phrase "composed of..." appears in a clause of the body of a claim rather than immediately following it, it limits only the elements described in that clause; other elements are not excluded from the claim as a whole.

[0033] When a dosage, concentration, or other value or parameter is expressed as a range, a preferred range, or a range defined by a series of upper and lower preferred values, this should be understood as specifically disclosing all ranges formed by any pair of any upper or preferred value with any lower or preferred value, regardless of whether the range is disclosed individually. For example, when the range “1 to 5” is disclosed, the described range should be interpreted as including ranges “1 to 4,” “1 to 3,” “1 to 2,” “1 to 2 and 4 to 5,” “1 to 3 and 5,” etc. When numerical ranges are described herein, unless otherwise stated, the range is intended to include its endpoints and all integers and fractions within that range.

[0034] In some instances, approximate terms may correspond to the instrument precision of the measured values. In this specification and claims, scope definitions may be combined and / or interchanged. Unless otherwise stated, these scopes include all subscopes contained therein.

[0035] The indefinite articles “a” and “an” preceding an element or component of this invention do not impose any limitation on the number of elements or components (i.e., the number of times they appear). Therefore, “an” or “a” should be interpreted as including one or at least one, and the singular form of an element or component also includes the plural form, unless the quantity clearly refers only to the singular form.

[0036] The terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., used in this invention refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms are not necessarily directed at the same embodiment or example. Furthermore, the technical features involved in the various embodiments of the invention can be combined with each other as long as they do not conflict with each other.

[0037] Unless otherwise specified, the raw materials and equipment used in this invention can be purchased from the market or are commonly used in the field. Unless otherwise specified, the methods in the embodiments are conventional methods in the field.

[0038] In some embodiments, an embodiment provides a method for preparing a modified 3D printed ceramic atomizing core substrate, the method comprising the following steps:

[0039] S1 is configured with ceramic slurry for 3D printing, and a porous ceramic precursor preform is 3D printed; then the slurry is removed.

[0040] S2. The porous ceramic precursor green body obtained after step S1 is sintered to obtain a 3D printed porous ceramic matrix.

[0041] S3 is configured with dipping and finishing paste;

[0042] S4. The porous ceramic precursor blank processed in step S1 or the 3D printed porous ceramic matrix obtained in step S2 is immersed in the dip modification slurry in step S3. After being immersed for a period of time, it is taken out and dried to obtain the modified 3D printed ceramic atomizing core matrix precursor.

[0043] S5 sinters the modified 3D printed ceramic atomizing core matrix precursor obtained in S4 to obtain the modified 3D printed ceramic atomizing core matrix.

[0044] In some embodiments, the ceramic slurry for 3D printing comprises a ceramic material, which is one or more of alumina, zirconium oxide, silicon oxide, silicon nitride, or ZTA. The ceramic material used is a general-purpose material. More preferably, to further improve the stability of the 3D printed porous ceramic atomizing core, ceramic materials of different particle sizes can be graded.

[0045] In some embodiments, the ceramic slurry further includes a binder and a solvent, wherein the weight ratio of ceramic material, binder, and solvent in the ceramic slurry is 70-90:2-5:10-30. The binder used may be one or more of polyurethane, epoxy resin, acrylate, epoxy acrylate, or ethyl cellulose, and the solvent used may be one or more of ethanol, propanol, butanol, etc. More preferably, the weight ratio of ceramic material, binder, and solvent in the ceramic slurry is 70-80:2-4:15-25; further preferably, the above weight ratio is 75-80:3:20-25; and further preferably, it is 75:3:22. Further, the binder may be ethyl cellulose, and the solvent may be ethanol.

[0046] In some embodiments, the ceramic material of the 3D printing paste is selected as Al2O3 powder with a D50 of 10-20 μm and Al2O3 powder with a D50 of 4-8 μm, and the mass ratio of the Al2O3 powder with a D50 of 10-20 μm to the Al2O3 powder with a D50 of 4-8 μm is 50-60:15-25; further, the above-mentioned ceramic material is selected as Al2O3 powder with a D50 of 15-20 μm and Al2O3 powder with a D50 of 5-8 μm; further, the weight ratio of the Al2O3 powder with a D50 of 15-20 μm to the Al2O3 powder with a D50 of 5-8 μm is 55:20.

[0047] In some embodiments, 3D printing a porous ceramic precursor blank specifically involves printing a cuboid containing cavities with external dimensions of 9*4.5*3.5mm, an internal cavity of 7*3*2mm, and pore diameter and spacing of 100μm uniformly distributed on a substrate, according to design drawings. Furthermore, the specific method for 3D printing the porous ceramic precursor blank can also be a conventional printing method and use common dimensions.

[0048] In some embodiments, the above-mentioned impregnation slurry includes ceramic material, binder and solvent, wherein the weight ratio of ceramic material, binder and solvent is 70-90:1-5:10-30, and the ceramic material is one or more of alumina, zirconium oxide, silicon oxide, silicon nitride or ZTA. Further, ceramic materials of different particle sizes can be graded. Selecting different particle sizes and different types of ceramic materials for gradation can improve the bonding force between the impregnation slurry and the ceramic substrate precursor.

[0049] In some embodiments, the ceramic material in the impregnation slurry is further comprising Al2O3 powder with a D50 of 15-25 μm, Al2O3 powder with a D50 of 4-8 μm, and SiO2 powder with a D50 of 15-25 μm, in a weight ratio of 40-50:10-20:10-20. Further, the ceramic material in the impregnation slurry is Al2O3 powder with a D50 of 20-25 μm, Al2O3 powder with a D50 of 5-6 μm, and SiO2 powder with a D50 of 20-25 μm, in a weight ratio of 45-50:15-20:10-15, and the weight ratio is further 45:15:15.

[0050] In some embodiments, the glue removal process in step S1 above involves heating the temperature to 400-500°C and holding it for 30-40 minutes, then heating it to 600-700°C and holding it for 40-80 minutes.

[0051] In some embodiments, the sintering process in step S2 above involves heating to 1300-1500°C and holding at that temperature for 3-6 hours. In some embodiments, the impregnation time in step S4 above is 5-30 seconds, and more specifically 10-20 seconds; the modified 3D printed ceramic atomizing core substrate precursor, after being impregnated with the slurry, undergoes further drying.

[0052] In some embodiments, the modified 3D printed ceramic atomized core substrate precursor, after drying before the sintering step in step S5, is programmed to be heated to 300-500°C and held for 1-5 hours, then programmed to be heated to 900-1500°C and held for 1-6 hours. Further, it is held at 300-500°C for 1-5 hours, and then sintered at 900-1400°C for 1-5 hours.

[0053] In some embodiments, the porous ceramic matrix obtained through the above steps includes two types of pore structures: macropores and micropores. Macropores are obtained by 3D printing, with a pore diameter and pore spacing of 100 μm. Micropores are obtained by attaching the modified slurry to the framework of macropores after sintering, with a pore diameter between 20-50 μm and a pore spacing between 20-100 μm, and the distribution is relatively uniform.

[0054] In some specific embodiments, a modified 3D printed ceramic atomizing core substrate is further provided. The modified 3D printed ceramic atomizing core substrate is prepared by the above-mentioned preparation method. The obtained modified 3D printed ceramic atomizing core substrate has a porous structure, including two types of pore structures: large pores with a diameter and spacing of 100 μm, and small pores with a diameter between 20-50 μm and a spacing between 20-100 μm, which are relatively uniformly distributed.

[0055] The following description, in conjunction with specific implementation methods, provides further details.

[0056] Example 1

[0057] Al2O3 powder with a D50 of 15μm, Al2O3 powder with a D50 of 5μm, ethyl cellulose, and ethanol were weighed in a weight ratio of 55:20:3:22 and mixed evenly to prepare a ceramic slurry for 3D printing. According to the design drawings, a cuboid with an external dimension of 9*4.5*3.5mm, an internal cavity of 7*3*2mm, and pore diameter and pore spacing of 100μm evenly distributed on the whole matrix was printed by 3D printing. The temperature was raised to 450 and 650℃ at a heating rate of 5℃ / min and held for 35 and 50min respectively to remove the organic binder in the system. Then, the temperature was raised to 1420℃ at a heating rate of 10℃ / min and held for 4h to sinter the finished product - the 3D printed porous ceramic matrix.

[0058] Al₂O₃ powder with a D50 of 20 μm, Al₂O₃ powder with a D50 of 5 μm, SiO₂ powder with a D50 of 20 μm, ethyl cellulose, and ethanol were weighed in a weight ratio of 45:15:15:1.5:23.5 and mixed evenly using a high-speed stirring device at a speed of 1000 r / min or higher to prepare a dipping and modifying slurry with a viscosity not exceeding 10000 mPa·s. The porous ceramic matrix obtained after sintering was immersed in the dipping and modifying slurry to ensure that the porous ceramic matrix was uniformly coated with the slurry. After 15 seconds, it was removed, excess slurry was cleaned off the surface, and then it was placed in a sintering furnace and sintered at 1350 °C at a heating rate of 10 °C / min. After holding at this temperature for 4 hours, it was removed to obtain the modified porous ceramic matrix.

[0059] SEM analysis revealed that the porous ceramic matrix contains both macropores and micropores. Macropores, obtained through 3D printing, have a diameter and spacing of 100 μm. Micropores, formed by sintering a modifying slurry and attaching it to the macropore framework, have a diameter between 20-50 μm and a spacing between 20-100 μm, exhibiting a relatively uniform distribution. Simultaneously, the 3D-printed ceramic framework also contains micropores of varying sizes, further forming a multi-level macropore structure with the modified porous ceramic and the 3D-printed framework. This structure is beneficial for improving the flavor of the vapor after atomization.

[0060] Tests showed that when e-liquid for electronic cigarette atomization was dripped into the cavity of the porous ceramic substrate, the e-liquid could penetrate into the porous ceramic substrate relatively quickly, but would not drip out of the cavity. This indicates that after modification, the porous ceramic substrate has both oil-guiding and oil-locking functions, which can meet the requirements for electronic cigarette atomization.

[0061] Example 2

[0062] Al2O3 powder with a D50 of 15μm, Al2O3 powder with a D50 of 5μm, ethyl cellulose, and ethanol were weighed in a weight ratio of 55:20:3:22 and mixed evenly to prepare a ceramic slurry for 3D printing. According to the design drawings, a cuboid containing a cavity with an external dimension of 9*4.5*3.5mm, an internal cavity of 7*3*2mm, and pore diameter and pore spacing of 100μm evenly distributed on the overall substrate was printed by 3D printing. After debinding, the temperature was raised to 450 and 650℃ at a heating rate of 5℃ / min and held for 35 and 50 min respectively to remove the organic binder in the system and obtain a porous ceramic green body.

[0063] Al₂O₃ powder with a D50 of 20 μm, Al₂O₃ powder with a D50 of 5 μm, SiO₂ powder with a D50 of 20 μm, ethyl cellulose, and ethanol were weighed in a weight ratio of 45:15:15:1.5:23.5 and mixed evenly using a high-speed stirring device at a speed of 1000 r / min or higher to prepare a dipping and modifying slurry with a viscosity not exceeding 10000 mPa·s. The porous ceramic blank, after the aforementioned debinding treatment, was immersed in the dipping and modifying slurry to ensure that the porous ceramic blank was uniformly coated with the slurry. After 15 seconds, it was removed, and excess slurry on the surface was cleaned off. Then, it was placed in a sintering furnace and sintered at 1350℃ at a heating rate of 10℃ / min. After holding at this temperature for 4 hours, it was removed to obtain the modified porous ceramic matrix.

[0064] SEM analysis revealed that the porous ceramic matrix contains both macropores and micropores. Macropores, obtained through 3D printing, have a diameter and spacing of 100 μm. Micropores, formed by sintering a modifying slurry and attaching it to the macropore framework, have a diameter between 20-50 μm and a spacing between 20-100 μm, exhibiting a relatively uniform distribution. Furthermore, the bonding between the 3D-printed structure and the slurry shows no obvious boundaries or cracks, appearing as a seamless whole. Simultaneously, the 3D-printed ceramic framework also contains micropores of varying sizes, further forming a multi-level macropore structure with the modified porous ceramic and the 3D-printed framework. This structure is beneficial for improving the flavor of the vapor after atomization.

[0065] Tests showed that when e-liquid for electronic cigarette atomization was dripped into the cavity of the porous ceramic substrate, the e-liquid could penetrate into the porous ceramic substrate relatively quickly, but would not drip out of the cavity. This indicates that after modification, the porous ceramic substrate has both oil-guiding and oil-locking functions, which can meet the requirements for electronic cigarette atomization.

[0066] The difference between Comparative Example 1 and Examples 1 and 2 is that there is no dip-in slurry step, and the porous ceramic green body printed directly by 3D printing is sintered to obtain the ceramic atomizing core matrix.

[0067] The difference between Comparative Example 2 and Examples 1 and 2 above is that there is no 3D printed porous ceramic skeleton. Instead, porous ceramic impregnation slurry is directly pressed into shape and then sintered at 1350°C for 4 hours to form the required porous ceramic structure.

[0068] The difference between Comparative Example 3 and Examples 1 and 2 is that in Comparative Example 3, all inorganic Al2O3 powder, SiO2 powder, and organic binders and solvents were mixed together in the same proportion (Al2O3 powder with D50 of 20μm, 15μm, and 5μm, SiO2 powder with D50 of 20μm, ethyl cellulose, and ethanol were weighed in the proportions of 45:55:35:15:4.5:45.5 respectively). After being stirred and dispersed evenly, the mixture was directly pressed into shape and then sintered at 1350℃ for 4 hours to obtain a porous ceramic matrix.

[0069] The difference between Comparative Example 4 and Example 1 lies in the formulation of the 3D printing ceramic slurry. The ratio of Al2O3 powder with a D50 of 15 μm to Al2O3 powder with a D50 of 5 μm was changed, reducing the proportion of the larger particle size (15 μm) powder and increasing the proportion of the smaller particle size (5 μm) powder. The final ratio is: Al2O3 powder with a D50 of 15 μm, Al2O3 powder with a D50 of 5 μm, ethyl cellulose, and ethanol in a weight ratio of 30:45:3:22, with the rest remaining unchanged. After sintering the 3D-printed ceramic skeleton, dipping it in the modification slurry, and undergoing a second sintering, modified 3D-printed porous ceramic is obtained.

[0070] SEM analysis revealed that the porous ceramic matrix differed from Example 1 in that the 3D-printed skeleton was dense with almost no pores. The porous ceramic matrix mainly consisted of macropores of approximately 100 μm obtained from 3D printing and micropores of approximately 30 μm from the modified ceramic. After being fabricated into an atomizing core, the flavor profile of the e-liquid was compared, and the smoothness of the flavor was inferior to that of Example 1.

[0071] The difference between Comparative Example 5 and Example 1 lies in the change of the powder ratio in the impregnation and modification slurry. The proportion of large-particle-size (20μm) powder was reduced, while the proportion of small-particle-size (5μm) powder was increased. The final addition ratio was 15:45:15:1.5:23.5 by weight, with the rest remaining unchanged. After sintering the 3D-printed ceramic skeleton, impregnating it with the modification slurry, and then sintering it again, modified 3D-printed porous ceramic was obtained.

[0072] SEM analysis revealed that the porous ceramic matrix differed from that of Example 1 in that it primarily consisted of macropores of approximately 100 μm obtained through 3D printing, along with micropores of approximately 10 μm created by modifying the ceramic. After fabricating the atomizing core, a comparison of the e-liquid's flavor upon vaping showed that the atomized core had a dry, burnt taste and failed to deliver the smooth, delicate flavor characteristic of e-liquids.

[0073] The test method for the oil conduction rate of porous ceramics is as follows:

[0074] 1. Place a white A4 sheet of paper under the porous ceramic substrate, with the inner cavity opening facing upwards;

[0075] 2. Completely wet the porous ceramic substrate with e-liquid;

[0076] 3. Fill the inner cavity of the porous ceramic substrate with e-liquid (the liquid level should be flush with the upper surface of the ceramic);

[0077] 4. After 60 seconds, the e-liquid imprints left on A4 paper after penetrating the porous ceramic substrate were observed and compared. The larger and wetter the imprint area, the faster the e-liquid conduction rate.

[0078] 5. Among them, Comparative Example 2, which was not modified with porous slurry, did not have such penetration behavior. The e-liquid flowed directly from the porous ceramic matrix to the paper surface, indicating that its e-liquid conduction rate was the fastest. Comparative Example 2, which did not have a 3D printed skeleton, showed almost no obvious e-liquid marks on the paper surface after 60 seconds, indicating that its e-liquid conduction rate was the slowest.

[0079] Table 1 Performance parameters of porous ceramic matrices in each embodiment

[0080]

[0081] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a modified 3D printed ceramic atomizing core substrate, characterized in that, The method includes the following steps: S1 is configured with ceramic slurry for 3D printing, and a porous ceramic precursor preform is 3D printed; then the slurry is removed. S2. The porous ceramic precursor green body obtained after step S1 is sintered to obtain a 3D printed porous ceramic matrix. S3 is prepared as an impregnation and finishing slurry; S4. The porous ceramic precursor blank processed in step S1 or the 3D printed porous ceramic matrix obtained in step S2 is immersed in the dip modification slurry in step S3. After being immersed for a period of time, it is taken out and dried to obtain the modified 3D printed ceramic atomizing core matrix precursor. S5. The modified 3D printed ceramic atomizing core matrix precursor obtained in S4 is sintered to obtain the modified 3D printed ceramic atomizing core matrix. The impregnation slurry includes ceramic materials, binders and solvents, wherein the weight ratio of ceramic materials, binders and solvents is 65-95:2-10:5-30; The ceramic materials in the impregnation slurry are Al2O3 powder with a D50 of 15-25μm, Al2O3 powder with a D50 of 4-8μm, and SiO2 powder with a D50 of 15-25μm, with a weight ratio of 40-50:10-30:10-30.

2. The method for preparing a modified 3D printed ceramic atomizing core substrate according to claim 1, characterized in that, The ceramic slurry for 3D printing contains a ceramic material, which is one or more of alumina, zirconium oxide, silicon oxide, silicon nitride, or ZTA (zirconia-toughened alumina).

3. The method for preparing a modified 3D printed ceramic atomizing core substrate according to claim 2, characterized in that, The ceramic slurry also includes a binder and a solvent, and the weight ratio of ceramic material, binder and solvent in the ceramic slurry is 65-95:2-10:5-30.

4. A method for preparing a modified 3D printed ceramic atomizing core substrate according to any one of claims 2-3, characterized in that, The ceramic material is selected as Al2O3 powder with a D50 of 5-20μm and Al2O3 powder with a D50 of 4-8μm, and the mass ratio of Al2O3 powder with D50 of 5-20μm and Al2O3 powder with D50 of 4-8μm is between 5:1 and 1:

5.

5. A method for preparing a modified 3D printed ceramic atomizing core substrate according to any one of claims 1-3, characterized in that, The glue removal process in step S1 involves heating the temperature to 400-500℃ at a rate of 0.1℃ / min-10℃ / min, holding it at that temperature for 30-40 minutes, and then heating it to 600-700℃ at a rate of 1℃ / min-10℃ / min and holding it at that temperature for 40-80 minutes.

6. A method for preparing a modified 3D printed ceramic atomizing core substrate according to any one of claims 1-3, characterized in that, The sintering process in step S2 involves heating the temperature to 1300-1500℃ at a rate of 1℃ / min-10℃ / min and holding it at that temperature for 3-6 hours.

7. A method for preparing a modified 3D printed ceramic atomizing core substrate according to any one of claims 1-3, characterized in that, The sintering process in step S5 involves heating the temperature to 800-1500℃ at a rate of 1℃ / min-10℃ / min and holding it at that temperature for 3-6 hours.

8. A modified 3D printed ceramic atomizing core substrate, characterized in that, The modified 3D printed ceramic atomizing core substrate is prepared using any one of the preparation methods described in claims 1-7.

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