Medium and low temperature ceramic atomization core and preparation method thereof

Abstract

The invention relates to a medium and low temperature ceramic atomization core and a preparation method thereof, the medium and low temperature ceramic atomization core comprises a heating body and an oil guide body, and the oil guide body comprises the following preparation raw materials: modified diatomite, glass powder, a pore forming agent and an additive; the preparation raw materials of the modified diatomite comprise diatomite and a modifier. The medium and low temperature ceramic atomization core has the advantages that the oil guide speed is high, the strength is high, the heating body is not prone to loosening, and the core is not prone to being pasted. The porosity of the modified diatomaceous earth is reduced, protrusions are formed, although liquid glass exists when the medium-low temperature ceramic atomization core is prepared, the amount of glass powder needed by the modified diatomaceous earth is reduced, meanwhile, the protrusions on the modified diatomaceous earth can play an inlaying role, and then the roughness of pore channels is increased; and the oil guide rate and the strength of the medium-low temperature ceramic atomizing core are improved.

Description

Technical Field

[0001] The present invention relates to the field of electronic atomization, and in particular to a medium-low temperature ceramic atomization core and a preparation method thereof. Background Art

[0002] Porous ceramic atomizer cores are widely used in the field of electronic cigarette atomizer cores due to their high porosity, excellent oil storage performance, good heating effect, energy saving, high temperature resistance, and difficulty in sticking the core. At present, porous ceramic atomizer cores are mainly made of silicon or aluminum raw materials as the main body of the ceramic skeleton. After adding certain binders and pore-forming agents, they are formed by hot pressing, dry pressing, casting, injection, etc., and then the porous ceramic matrix is ​​obtained by debinding and sintering. Then, the porous ceramic atomizer core is obtained by combining it with the heating element by printing thick film, inlaying steel sheets, inlaying nautilus heating wires, and coating. No matter which combination method is used for the heating element and the porous ceramic matrix, if the two are not well combined, the heating element part of the atomizer core will be warped, loosened or fall off, which will greatly affect the service life of the atomizer core. In addition, carbon deposition and fracture are prone to occur on the surface of the heating element of the atomizer core, affecting the suction experience. The porous ceramic atomization core is divided into a high-temperature porous ceramic atomization core and a medium- and low-temperature porous ceramic atomization core. The sintering temperature of the high-temperature porous ceramic atomization core is higher than 1000°C, and the sintering temperature of the medium- and low-temperature porous ceramic atomization core is lower than 1000°C.

[0003] At present, the medium and low temperature porous ceramic atomization cores used in the market mostly use diatomaceous earth and quartz sand, silicon oxide, aluminum oxide, etc. as ceramic bone powder, use low-temperature glass powder for bonding, and then use etched sheets or nautilus as heating elements to form an atomization core. Under the sintering temperature of several hundred degrees Celsius, the micropores of diatomaceous earth or porous inorganic powders have a strong capillary effect on the liquid glass powder, so that the liquid glass is filled into the micropores on the diatomaceous earth or porous inorganic powders, resulting in a decrease in the glass content that plays a bonding role, and then the strength of the atomization core is reduced; if the glass powder content is increased, the medium and low temperature ceramic atomization core will suffer from severe thermal shrinkage, the pore size will become smaller and the porosity will decrease, which will affect the liquid conduction rate. Therefore, it is difficult to achieve a balance between the liquid conduction rate and strength of the medium and low temperature porous ceramic atomization core. Summary of the invention

[0004] In order to overcome the problems existing in the prior art, one of the objectives of the present invention is to provide a method for preparing modified diatomite.

[0005] A second object of the present invention is to provide a modified diatomaceous earth.

[0006] A third object of the present invention is to provide a medium to low temperature ceramic atomization core.

[0007] A fourth object of the present invention is to provide a method for preparing a medium- and low-temperature ceramic atomization core.

[0008] A fifth object of the present invention is to provide an electronic atomization device.

[0009] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0010] A first aspect of the present invention provides a method for preparing modified diatomite, comprising the following steps:

[0011] Mix and grind diatomite with an alcohol solvent, then mix and grind with a modifier, and then sinter at 1000-1300 °C to obtain the modified diatomite;

[0012] The modifier includes at least one of a mixture of carbonate and aluminum oxide, silica sol, silicate, aluminate, and aluminosilicate;

[0013] Or the modifier is a mixture that reacts at 1000-1300 °C to form silicate, aluminate, or aluminosilicate;

[0014] Or, the modifier is a mixture that forms silicon-oxygen bonds or silicon-aluminum bonds at 1000-1300 °C.

[0015] Preferably, the modifier includes at least one of a mixture of sodium carbonate and aluminum oxide, a mixture of potassium carbonate and aluminum oxide, sodium silicate, potassium silicate, calcium silicate, magnesium silicate, sodium aluminate, potassium aluminate, calcium aluminate, magnesium aluminate, sodium aluminosilicate, and potassium aluminosilicate.

[0016] Preferably, the alcohol solvent is selected from at least one of methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, propylene glycol, and glycerol. The alcohol solvent can remove the water in the modifier, extract the modifier, and then continue to disperse to form a uniformly dispersed gel.

[0017] Preferably, the modifier further includes water.

[0018] Preferably, in the mixing and grinding with the modifier, the mixing and grinding time is 1-4 h; more preferably, the mixing and grinding time is 1-3 h.

[0019] Preferably, in the step of mixing and grinding diatomite with an alcohol solvent, the mixing and grinding time is 30-90 min.

[0020] Preferably, in the method for preparing modified diatomite, the mixing and grinding step is carried out by mixing ball milling with grinding balls.

[0021] Preferably, in the method for preparing modified diatomite, the mass ratio of the grinding balls to the powder is 1:0.8-1.2.

[0022] Preferably, the preparation method further includes a step of grinding and crushing after the sintering step; more preferably, the preparation method further includes a step of grinding and crushing through a 140-160 mesh sieve after the sintering step.

[0023] The second aspect of the present invention provides a modified diatomite, which is prepared by using the preparation method provided in the first aspect of the present invention.

[0024] The third aspect of the present invention provides a medium and low temperature ceramic atomizing core, which includes a heating element and an oil guiding body. The oil guiding body includes the following preparation raw materials: the modified diatomite provided in the second aspect of the present invention, glass powder, pore-forming agent and additive; the preparation raw materials of the modified diatomite include diatomite and modifier.

[0025] Preferably, the oil guiding body includes the following preparation raw materials in mass percentages: 10-50% of diatomite, 0-20% of ceramic powder, 5-20% of glass powder, 0.1-10% of silicate or silica sol, 7-30% of pore-forming agent, 10-30% of additive.

[0026] Preferably, the glass powder contains silicon element, zinc element, boron element and aluminum element. The glass powder in the present invention contains silicon element, zinc element, boron element and aluminum element, that is, silicon-zinc-boron-aluminum low-temperature glass powder.

[0027] Preferably, the ceramic powder is selected from at least one of quartz sand, silica powder and kaolinite; more preferably, the ceramic powder is silica powder.

[0028] Preferably, the mass ratio of the diatomite to the silica powder is 1:1-4.5.

[0029] Preferably, the pore-forming agent is selected from at least one of flour, polymethyl methacrylate and wood fiber.

[0030] Preferably, the additive is selected from at least one of paraffin, polyethylene, stearic acid and oleic acid.

[0031] Preferably, based on the total mass percentage of the preparation raw materials of the oil guiding body being 100%, the additive includes the following components in mass percentages: 8-20% of paraffin, 1-5% of polyethylene, 0.5-2% of stearic acid, 0.5-3% of oleic acid.

[0032] Preferably, the oil guiding body includes the following preparation raw materials in mass percentages: 10-50% of diatomite, 0-20% of ceramic powder, 5-20% of glass powder, 0.1-10% of silicate or silica sol, 7-30% of pore-forming agent, 8-20% of paraffin, 1-5% of polyethylene, 0.5-2% of stearic acid, 0.5-3% of oleic acid.

[0033] Preferably, based on the total mass percentage of the oil guiding body being 100%, the mass percentage of the glass powder is 8-16%; more preferably, the mass percentage of the glass powder is 10-13%.

[0034] Preferably, based on the total mass percentage of the oil guiding body being 100%, the mass percentage of the pore-forming agent is 7-16%; more preferably, the mass percentage of the pore-forming agent is 7-10%.

[0035] Preferably, based on the total mass percentage of the oil guiding body being 100%, the mass percentage of the paraffin wax is 10-20%; more preferably, the mass percentage of the paraffin wax is 12-19%.

[0036] Preferably, the glass powder comprises the following raw materials in mass percentages for preparation: 35-45% silicon dioxide, 20-25% zinc oxide, 5-20% boric acid, 2-10% aluminum hydroxide, 5-10% sodium oxide, 1-2% titanium oxide, 0.5-1.5% potassium oxide.

[0037] Preferably, based on the total mass percentage of the glass powder being 100%, the mass percentage of the silicon dioxide is 36-42%; more preferably, the mass percentage of the silicon dioxide is 38-41%.

[0038] Preferably, based on the total mass percentage of the glass powder being 100%, the mass percentage of the zinc oxide is 23-25%.

[0039] Preferably, based on the total mass percentage of the glass powder being 100%, the mass percentage of the boric acid is 18-20%.

[0040] Preferably, based on the total mass percentage of the glass powder being 100%, the mass percentage of the aluminum hydroxide is 3-8%; more preferably, the mass percentage of the aluminum hydroxide is 5-6%.

[0041] Preferably, based on the total mass percentage of the glass powder being 100%, the mass percentage of the sodium oxide is 6-9%; more preferably, the mass percentage of the sodium oxide is 8-9%.

[0042] The fourth aspect of the present invention provides a preparation method of a medium and low temperature ceramic atomization core, and the preparation method comprises the following steps:

[0043] Step 1: Prepare a modified diatomite, a glass powder, and an additive melt respectively;

[0044] The preparation method of the modified diatomite is: mixing and grinding diatomite with an alcohol solvent, then mixing and grinding with a modifier, and then sintering at 1000-1300 °C to obtain the modified diatomite;

[0045] Step 2: Mix and grind the preparation raw materials including modified diatomite, glass powder, and pore former, then mix with the additive melt, and then use the hot pressing or injection molding process to make the oil guiding body blank;

[0046] Step 3: Debind and sinter the oil guiding body blank to obtain the oil guiding body;

[0047] Step 4: Form a heating element on the oil guiding body by coating or printing to obtain the medium and low temperature ceramic atomization core;

[0048] Or, the preparation method includes the following steps:

[0049] Step 1: Prepare modified diatomite, glass powder, additive melt, and heating element respectively;

[0050] Step 2: Mix and grind the preparation raw materials including modified diatomite, glass powder, and pore former, then mix with the additive melt to obtain a ceramic slurry, and then inject the ceramic slurry into a mold with a heating element placed inside to form a ceramic atomization core blank;

[0051] Step 3: Debind and sinter the ceramic atomization core blank to obtain the medium and low temperature ceramic atomization core.

[0052] Preferably, the preparation method of the additive melt is: heat and melt the additive to make the additive melt.

[0053] Preferably, Step 2 is: grind and mix the modified diatomite, ceramic powder, glass powder, and pore former, then mix with the additive melt, and then use the hot pressing or injection molding process to make the oil guiding body blank; Further preferably, Step 2 is: grind and mix the modified diatomite, ceramic powder, glass powder, and pore former for 1 - 3 h, then mix with the additive melt, and then use the hot pressing or injection molding process to make the oil guiding body blank.

[0054] Preferably, the mixing and grinding step in Step 2 is carried out using grinding balls.

[0055] Preferably, in Step 2, the mass ratio of the grinding balls to the preparation raw materials is 1:0.8 - 1.2.

[0056] Preferably, the preparation method of the glass powder is: mix and grind the raw materials for preparing the glass powder, then calcine at 1400 - 1600 °C for 1.5 - 3 h, and then water quench to obtain the glass powder. Further preferably, the preparation method of the glass powder is: mix and grind the raw materials for preparing the glass powder evenly, then calcine at 1400 - 1600 °C for 2 - 3 h, then water quench, dry, grind through a 2000 - mesh sieve to obtain the glass powder.

[0057] Preferably, in the third step, the sintering temperature is 720 - 750 °C.

[0058] The fifth aspect of the present invention provides an electronic atomization device, including the medium - low temperature ceramic atomization core provided by the third aspect of the present invention.

[0059] The electronic atomization device in the present invention has all the features and advantages of the medium - low temperature ceramic atomization core provided by the third aspect of the present invention.

[0060] The beneficial effects of the present invention are as follows: The medium - low temperature ceramic atomization core in the present invention has the advantages of fast oil - guiding rate, high strength, the heating element is not easy to loosen, and not easy to get coked. Specifically:

[0061] (1) The porosity of the modified diatomite in the present invention decreases and forms protrusions. Although there is liquid glass when preparing the medium - low temperature ceramic atomization core, the amount of glass powder required for the modified diatomite is reduced. At the same time, the protrusions on the modified diatomite can play an embedding role, thereby increasing the pore channel roughness, and increasing the oil - guiding rate and strength of the medium - low temperature ceramic atomization core.

[0062] (2) The present invention uses silicon - zinc - boron - aluminum low - temperature glass powder. This glass powder not only has high strength itself but also has good adhesiveness to metal materials, and is also well - dispersed with the modified diatomite, which enhances the bonding force between the ceramic matrix and the heating element, making the heating element not easy to loosen or deform, solving the problem of poor bonding force between the ceramic substrate and the etched - sheet heating element / nautilus heating wire in the existing medium - low temperature ceramic atomization core, and thus increasing the service life of the medium - low temperature ceramic atomization core. In addition, compared with the ceramic matrix in the prior art, the ceramic matrix of the medium - low temperature ceramic atomization core in the present invention has an extremely small shrinkage rate, and there will be no phenomenon of the heating element separation or the deformation of the ceramic atomization core caused by the inconsistent shrinkage of the ceramic matrix and the heating element. Therefore, the medium - low temperature ceramic atomization core in the present invention has a high yield rate. Description of the Drawings

[0063] Figure 1 SEM image of diatomite raw material.

[0064] Figure 2 SEM image of the modified diatomite in Example 1. Detailed Embodiments

[0065] The following further elaborates on the specific implementation of the present invention in conjunction with the drawings and examples, but the implementation and protection of the present invention are not limited thereto. It should be noted that for the processes not specifically described in detail below, those skilled in the art can refer to the prior art to implement or understand. The reagents or instruments used without indicating the manufacturer are all conventional products that can be purchased commercially.

[0066] Example 1

[0067] This example provides a method for preparing modified diatomaceous earth. The specific modification steps are as follows:

[0068] Step 1: Dissolve 10 g of sodium silicate in 50 mL of deionized water to prepare a sodium silicate solution;

[0069] Step 2: Mix 200 g of diatomaceous earth with alcohol and ball-mill for 30 min to fully disperse the diatomaceous earth. The mass ratio of the grinding balls to the diatomaceous earth is 1:1; then pour the sodium silicate solution into the ball-mill tank and continue ball-milling for 2 h, dry it, keep it at a high temperature of 1200 °C for 60 min, then cool and ball-mill and crush it, and pass through a 150-mesh sieve to obtain the modified diatomaceous earth in this example. In this step, the diameter of the modified diatomaceous earth can be controlled by controlling the ball-milling time and ball-milling speed, and then screening through a sieve with a specific mesh number can achieve the purpose of adjusting the size of the modified diatomaceous earth according to the use requirements.

[0070] The SEM images of diatomaceous earth and the modified diatomaceous earth in this example are respectively detected. Among them, Figure 1 is the SEM image of unmodified diatomaceous earth, Figure 2 is the SEM image of the modified diatomaceous earth in this example. The original appearance of diatomaceous earth is a biogenic siliceous sedimentary rock, which is mainly composed of the remains of ancient diatoms. Therefore, the microscopic morphology of diatomaceous earth shows a disc shape and has many micropores. This natural structure makes diatomaceous earth have the following advantages: strong adsorption performance, light bulk density, uniform fineness, neutral and non-toxic pH value, good mixing uniformity. Therefore, diatomaceous earth becomes the first choice of silicon source when preparing porous ceramic oil conductors. When preparing a high-temperature ceramic atomization core, the sintering temperature is as high as above 1000 °C and even reaches 1400 °C. The introduction of diatomaceous earth can improve the oil conduction rate and oil locking ability of the ceramic oil conductor. However, when preparing a medium- and low-temperature ceramic oil conductor, the use of diatomaceous earth brings greater drawbacks. For example, due to the low sintering temperature, the diatomaceous earth is not fully sintered, and glass powder needs to be added to play a role of melting and bonding. However, if too little glass powder is added, the strength of the ceramic oil conductor is low, and if too much glass powder is added, the porosity of the diatomaceous earth is significantly reduced, losing its original advantages, and at the same time, the oil conduction rate of the prepared medium- and low-temperature ceramic atomization core will also be reduced. Therefore, the present invention modifies the diatomaceous earth. As Figures 1 - 2 can be seen, compared with unmodified diatomaceous earth, the diameter of the modified diatomaceous earth in this example is about 38.88 μm, and the number of micropores decreases and the porosity decreases. When preparing a medium- and low-temperature ceramic core body, the addition amount of glass powder can be reduced, thereby improving the strength of the prepared medium- and low-temperature ceramic atomization core body. In addition, protrusions are formed in the modified diatomaceous earth, and these protrusions can play an embedding role and can also increase the roughness to improve the liquid conduction rate of the medium- and low-temperature ceramic atomization core. Therefore, by using the modified diatomaceous earth, the prepared medium- and low-temperature ceramic atomization core body can have both a high oil conduction rate and strength.

[0071] Example 2

[0072] This example provides a preparation method of modified diatomite. The specific modification steps are as follows:

[0073] Step 1: Dissolve 100 g of sodium silicate in 500 mL of deionized water to prepare a sodium silicate solution;

[0074] Step 2: Mix 500 g of diatomite with alcohol and ball-mill for 45 min to fully disperse the diatomite. The mass ratio of the grinding balls to the diatomite is 1:1; then pour the sodium silicate solution into the ball-mill tank and continue ball-milling for 3 h, dry, keep it at a high temperature of 1000 °C for 30 min, then cool and ball-mill and crush it, and pass through a 150-mesh sieve to obtain the modified diatomite in this example.

[0075] Example 3

[0076] This example provides a preparation method of modified diatomite. The specific modification steps are as follows:

[0077] Step 1: Dissolve 100 g of potassium silicate in 500 mL of deionized water to prepare a potassium silicate solution;

[0078] Step 2: Mix 1000 g of diatomite with alcohol and ball-mill for 45 min to fully disperse the diatomite. The mass ratio of the grinding balls to the diatomite is 1:1; then pour the potassium silicate solution into the ball-mill tank and continue ball-milling for 3 h, dry, keep it at a high temperature of 1100 °C for 45 min, then cool and ball-mill and crush it, and pass through a 150-mesh sieve to obtain the modified diatomite in this example.

[0079] In Examples 1 to 3, alcohol is used as a solvent during ball-milling, so that alcohol takes away the water in the sodium silicate / potassium silicate aqueous solution, extracts the sodium silicate / potassium silicate, and then continues to disperse to form a gel-like substance that sinks to the bottom and is evenly dispersed. If the diatomite and the sodium silicate / potassium silicate aqueous solution are directly mixed without alcohol extraction, the sodium silicate / potassium silicate will not be evenly dispersed. In addition, the sodium silicate / potassium silicate solution in Examples 1 to 3 of the present invention can be replaced with silica sol, a mixture of sodium carbonate and aluminum oxide, a mixture of potassium carbonate and aluminum oxide, calcium silicate, magnesium silicate, sodium aluminate, potassium aluminate, calcium aluminate, magnesium aluminate, sodium aluminosilicate, potassium aluminosilicate.

[0080] Example 4

[0081] This example provides a medium and low temperature ceramic atomization core. The medium and low temperature ceramic atomization core includes a heating element and an oil guiding element. The preparation raw materials and their dosages of the oil guiding element are shown in Table 1:

[0082] Table 1 Formulation of the oil guiding element in Example 4

[0083] Preparation raw materials Dosage (g) Silica powder 900 Diatomaceous earth 200 Sodium silicate 10 Glass powder 220 Pore former 180 Paraffin wax 230 Polyethylene 30 Stearic acid 15 Oleic acid 20

[0084] This example provides a method for preparing a medium-low temperature ceramic atomization core, and the specific preparation steps are as follows:

[0085] Step 1: Prepare glass powder: Mix 450 g of silicon oxide, 250 g of zinc oxide, 200 g of boric acid, 60 g of aluminum hydroxide, 70 g of sodium oxide, 15 g of titanium oxide, and 15 g of potassium oxide evenly by ball milling, keep it at high temperature melting at 1600 °C for 2 h, quench with water, dry, and then ball mill through a 2000-mesh sieve to obtain it;

[0086] Prepare modified diatomite: Select the diatomite and sodium silicate in the amounts shown in Table 1, and prepare the modified diatomite from the diatomite and sodium silicate according to the method in Example 1;

[0087] Step 2: Mix 900 g of modified diatomite, 900 g of silica powder, 220 g of glass powder, and 180 g of pore-forming agent and ball mill for 2 h. The mass ratio of the grinding balls to the raw materials is 1:1 to obtain a ceramic mixed powder;

[0088] Step 3: Melt and mix 230 g of paraffin wax and 30 g of polyethylene, and add 15 g of stearic acid and 20 g of oleic acid to obtain a molten liquid;

[0089] Step 4: Mix and stir the ceramic mixed powder and the molten liquid evenly, and use the hot pressing or injection molding method to obtain an oil guiding body blank;

[0090] Step 5: Keep the oil guiding body blank at 730 °C for 60 min for dewaxing sintering to obtain an oil guiding body;

[0091] Step 6: Form a heating element on the oil guiding body by printing to obtain the medium-low temperature ceramic atomization core of this example.

[0092] Example 5

[0093] This example provides a medium-low temperature ceramic atomization core body, which includes a heating element and an oil guiding body. The preparation raw materials and their dosages of the oil guiding body are shown in Table 2:

[0094] Table 2 Formulation of the oil guiding body in Example 5

[0095] Preparation raw materials Dosage (g) Silica powder 500 Diatomaceous earth 500 Sodium silicate 100 Glass powder 200 Pore former 160 Paraffin wax 300 Polyethylene 50 Stearic acid 10 Oleic acid 40

[0096] This example provides a method for preparing a medium-low temperature ceramic atomization core, and the specific preparation steps are as follows:

[0097] Step 1: Prepare glass powder: Mix 450 g of silicon oxide, 250 g of zinc oxide, 200 g of boric acid, 60 g of aluminum hydroxide, 70 g of sodium oxide, 15 g of titanium oxide, and 15 g of potassium oxide together and ball mill evenly, keep it at high temperature melting at 1600 °C for 2 h, quench with water, dry, and then ball mill through a 2000-mesh sieve to obtain it;

[0098] Preparation of modified diatomite: Select the diatomite and sodium silicate in the amounts shown in Table 2, and prepare the modified diatomite from the diatomite and sodium silicate according to the method in Example 2;

[0099] Step 2: Mix 500 g of modified diatomite, 500 g of silica powder, 200 g of glass powder, and 160 g of pore-forming agent and ball-mill for 2 h. The mass ratio of the grinding balls to the raw materials for preparation is 1:1. After grinding, a ceramic mixed powder is obtained;

[0100] Step 3: Melt and mix 300 g of paraffin wax and 50 g of polyethylene, and add 10 g of stearic acid and 40 g of oleic acid to obtain a molten liquid;

[0101] Step 4: Mix and stir the ceramic mixed powder and the molten liquid evenly to obtain a ceramic slurry, and then inject the ceramic slurry into a mold containing a heating element by hot pressing or injection molding to form a ceramic atomization core blank;

[0102] Step 5: Sinter the ceramic atomization core blank at 750 °C for 30 min to remove the wax, and obtain the medium-low temperature ceramic atomization core in this example.

[0103] Example 6

[0104] This example provides a medium-low temperature ceramic atomization core body, which includes a heating element and an oil guiding body. The raw materials for preparing the oil guiding body and their dosages are shown in Table 3:

[0105] Table 3 Formulation of the oil guiding body in Example 6

[0106] Preparation raw materials Dosage (g) Diatomaceous earth 1000 Potassium silicate 100 Glass powder 230 Pore former 160 Paraffin wax 370 Polyethylene 80 Stearic acid 12 Oleic acid 50

[0107] This example provides a preparation method for a medium-low temperature ceramic atomization core. The specific preparation steps are as follows:

[0108] Step 1: Preparation of glass powder: Mix 450 g of silicon oxide, 250 g of zinc oxide, 200 g of boric acid, 60 g of aluminum hydroxide, 70 g of sodium oxide, 15 g of titanium oxide, and 15 g of potassium oxide, ball-mill evenly, keep at a high temperature of 1600 °C for 2 h, quench with water, dry, and ball-mill through a 2000-mesh sieve to obtain;

[0109] Preparation of modified diatomite: Select the diatomite and sodium silicate in the amounts shown in Table 3, and prepare the modified diatomite from the diatomite and potassium silicate according to the method in Example 3;

[0110] Step 2: Mix 230 g of modified diatomite, 230 g of glass powder, and 160 g of pore-forming agent and ball-mill for 2 h. The mass ratio of the grinding balls to the raw materials for preparation is 1:1. After grinding, a ceramic mixed powder is obtained;

[0111] Step 3: Melt and mix 370 g of paraffin wax and 80 g of polyethylene, and add 12 g of stearic acid and 50 g of oleic acid to obtain a molten liquid;

[0112] Step 4: Mix the ceramic mixed powder and the molten liquid evenly to obtain a ceramic slurry, and then inject the ceramic slurry into a mold with a heating element by hot pressing or injection molding to form a ceramic atomization core blank body;

[0113] Step 5: Keep the ceramic atomization core blank body at 750 °C for 60 min for dewaxing sintering to obtain the medium and low temperature ceramic atomization core in this example.

[0114] Example 7

[0115] Compared with Example 5, the glass powder in the preparation raw materials used for the oil guiding body in the medium and low temperature ceramic atomization core in this example is different. The formula of the glass powder used in this example is shown in Table 4:

[0116] Table 4 Formula of Glass Powder

[0117] Preparation raw materials Dosage (g) Silicon oxide 430 Zinc oxide 250 Boric acid 200 Aluminum hydroxide 60 Sodium oxide 90 Titanium oxide 12 Potassium oxide 15

[0118] The difference between the preparation method of the medium and low temperature ceramic atomization core in this example and that in Example 5 lies in: the preparation method of the glass powder is different. The preparation method of the glass powder in this example is: Mix the raw materials of the glass powder in Table 4 evenly by ball milling, keep it at a high temperature of 1600 °C for melting and heat preservation for 1.5 h, quench with water, dry, and ball mill through a 2000-mesh sieve to obtain it.

[0119] Example 8

[0120] Compared with Example 5, the glass powder in the preparation raw materials used for the oil guiding body in the medium and low temperature ceramic atomization core in this example is different. The formula of the glass powder used in this example is shown in Table 5:

[0121] Table 5 Formula of Glass Powder

[0122] Preparation raw materials Dosage (g) Silicon oxide 410 Zinc oxide 250 Boric acid 200 Aluminum hydroxide 60 Sodium oxide 90 Titanium oxide 12 Potassium oxide 15

[0123] The difference between the preparation method of the medium and low temperature ceramic atomization core in this example and that in Example 5 lies in: the preparation method of the glass powder is different. The preparation method of the glass powder in this example is: Mix the raw materials of the glass powder in Table 5 evenly by ball milling, keep it at a high temperature of 1500 °C for melting and heat preservation for 2 h, quench with water, dry, and ball mill through a 2000-mesh sieve to obtain it.

[0124] Example 9

[0125] Compared with Example 5, the glass powder in the preparation raw materials used for the oil guiding body in the medium and low temperature ceramic atomization core in this example is different. The formula of the glass powder used in this example is shown in Table 6:

[0126] Table 6 Formula of Glass Powder

[0127] Preparation raw materials Dosage (g) Silicon oxide 390 Zinc oxide 250 Boric acid 200 Aluminum hydroxide 60 Sodium oxide 90 Titanium oxide 12 Potassium oxide 15

[0128] The preparation method of the medium and low temperature ceramic atomizing core in this example is different from that of the medium and low temperature ceramic atomizing core in Example 5 in that: the preparation method of the glass powder is different. The preparation method of the glass powder in this example is as follows: Mix the raw materials of the glass powder in Table 6 evenly by ball milling, keep it at a high temperature of 1400 °C for melting and heat preservation for 2.5 h, perform water quenching, drying, and ball milling through a 2000-mesh sieve to obtain it.

[0129] Comparative Example 1

[0130] This example provides a medium and low temperature ceramic atomizing core body, which includes a heating element and an oil guiding body. The preparation raw materials and their dosages of the oil guiding body are shown in Table 7:

[0131] Table 7 Formulation of the oil guiding body in Comparative Example 1

[0132] Preparation raw materials Dosage (g) Silica powder 1100 Glass powder 180 Pore former 350 Paraffin wax 200 Polyethylene 20 Stearic acid 15 Oleic acid 15

[0133] This example provides a preparation method of a medium and low temperature ceramic atomizing core. The specific preparation steps are as follows:

[0134] Step 1: Prepare glass powder: Mix 450 g of silicon dioxide, 250 g of zinc oxide, 200 g of boric acid, 60 g of aluminum hydroxide, 70 g of sodium oxide, 15 g of titanium oxide, and 15 g of potassium oxide evenly by ball milling, keep it at a high temperature of 1600 °C for melting and heat preservation for 2 h, perform water quenching, drying, and ball milling through a 2000-mesh sieve to obtain it;

[0135] Step 2: Mix 1100 g of silicon micropowder, 180 g of glass powder, and 350 g of pore-forming agent and ball mill for 2 h. The mass ratio of the grinding balls to the preparation raw materials is 1:1. After grinding, obtain ceramic mixed powder;

[0136] Step 3: Melt and mix 200 g of paraffin wax and 20 g of polyethylene, add 15 g of stearic acid and 15 g of oleic acid to obtain a molten liquid;

[0137] Step 4: Mix and stir the ceramic mixed powder and the molten liquid evenly to obtain ceramic slurry, and then inject the ceramic slurry into a mold with a heating element by hot pressing or injection molding to form a ceramic atomizing core blank;

[0138] Step 5: Keep the ceramic atomizing core blank at 720 °C for 90 min for dewaxing and sintering to obtain the medium and low temperature ceramic atomizing core in this example.

[0139] Comparative Example 2

[0140] This example provides a medium and low temperature ceramic atomizing core body, which includes a heating element and an oil guiding body. The preparation raw materials and their dosages of the oil guiding body are shown in Table 8:

[0141] Formulation of the oil guiding body in Comparative Example 2

[0142] Preparation raw materials Dosage (g) Diatomaceous earth 1100 Glass powder 180 Pore former 350 Paraffin wax 200 Polyethylene 20 Stearic acid 15 Oleic acid 15

[0143] The preparation method of the medium and low temperature ceramic atomization core in this example was prepared with reference to the preparation method of the medium and low temperature ceramic atomization core in Comparative Example 1.

[0144] Comparative Example 3

[0145] The medium and low temperature ceramic atomization core in this example was prepared by the following preparation method. The specific steps are as follows:

[0146] Step 1: Take 100 g of diatomite, add 40 g of alumina, 20 g of calcium carbonate, and 40 g of silicon carbide respectively, mix in a rolling mill for 3 h, then add 400 g of a sodium silicate aqueous solution with a mass fraction of 10%, fully mix and stir for 30 min, and then place it in an oven at 150 °C for drying for 15 h.

[0147] Step 2: Place the dried block in a ball mill for crushing. The mass of the grinding balls is 3 times the mass of the block, and the ball milling time is 2 h. Screen the powder obtained after ball milling on an 80-mesh sieve to obtain ceramic powder.

[0148] Step 3: Add 96 g of mineral wax, 12 g of oleic acid, 12 g of polymethyl methacrylate, and 80 g of wood fibers with a particle size of 40 μm to the ceramic powder, and mix in a mixer under vacuum conditions for 3 h at a mixing temperature of 150 °C to obtain a ceramic slurry.

[0149] Step 4: Place the ceramic slurry in the hopper of a medium-pressure injection molding device for stirring, and at the same time perform vacuum treatment on the hopper. Adjust the injection temperature to 120 °C, inject the ceramic slurry into the mold with a heating element placed inside, the injection pressure is 2 MPa, and the pressure holding time is 5 s to obtain a green body of the ceramic atomization core.

[0150] Step 5: Place the green body of the ceramic atomization core in a sintering furnace, and perform dewaxing sintering at 720 °C for 90 min to obtain the medium and low temperature ceramic atomization core in this example.

[0151] Performance test:

[0152] Respectively test the volume shrinkage rate, strength, open porosity, base oil guiding rate, and average pore diameter of the medium and low temperature ceramic atomization cores in Examples 4-9 and Comparative Examples 1-3. Then install the medium and low temperature ceramic atomization cores in Examples 4-9 and Comparative Examples 1-3 in the same electronic atomization device respectively. After sucking 1000 puffs, disassemble and assemble the electronic atomization device, and observe whether the heating element in the atomization core is loose and whether the atomization core shows a phenomenon of coking.

[0153] The volume shrinkage rate refers to the volume shrinkage of the medium- and low-temperature ceramic atomizing core green body before and after dewaxing treatment, and its calculation formula is: Volume shrinkage rate = (V 排蜡前 - V 排蜡后 ) / V 排蜡前 ;

[0154] The strength was tested according to the GB / T 40005-2021 standard. The test results obtained by the above test method are shown in Table 9.

[0155] Table 9 Performance test results of medium- and low-temperature ceramic atomizing cores in Examples 4-9 and Comparative Examples 1-2

[0156]

[0157] As can be seen from Table 9, compared with Comparative Examples 1-2, the medium- and low-temperature ceramic atomizing cores prepared in Examples 4-9 of the present invention using modified diatomite as the main body of the ceramic skeleton have the advantages of fast oil guiding rate, high strength, the heating element is not easy to loosen, and not easy to clog the core. While the medium- and low-temperature ceramic atomizing core prepared by the unmodified diatomite formula in Comparative Example 3 at 720 °C for debinding and sintering has extremely low strength and cannot be installed in an electronic atomizing device for use, that is, it cannot meet the strength requirements for the use of the atomizing core.

[0158] In summary, the medium- and low-temperature ceramic atomizing core in the present invention has the advantages of fast oil guiding rate, high strength, the heating element is not easy to loosen, and not easy to clog the core, specifically:

[0159] (1) The porosity of the modified diatomite in the present invention is reduced and protrusions are formed. Although there is liquid glass when preparing the medium- and low-temperature ceramic atomizing core, the amount of glass powder required for the modified diatomite is reduced. At the same time, the protrusions on the modified diatomite can play an embedding role, thereby increasing the pore channel roughness and increasing the oil guiding rate and strength of the medium- and low-temperature ceramic atomizing core.

[0160] (2) The present invention uses silicon-zinc-boron-aluminum low-temperature glass powder. This glass powder not only has high strength itself but also has good adhesion to metal materials, and is also well dispersed with the modified diatomite, so that the bonding force between the ceramic matrix and the heating element is enhanced, and the heating element is not easy to loosen or deform, solving the problem of poor bonding force between the ceramic base material and the etched sheet heating element / nautilus heating wire in the existing medium- and low-temperature ceramic atomizing cores, thereby increasing the service life of the medium- and low-temperature ceramic atomizing core. In addition, compared with the ceramic matrix in the prior art, the ceramic matrix of the medium- and low-temperature ceramic atomizing core in the present invention has an extremely small shrinkage rate, less than 0.5%, and there will be no phenomenon of the heating element separating or the medium- and low-temperature ceramic atomizing core deforming due to inconsistent shrinkage of the ceramic matrix and the heating element. Therefore, the medium- and low-temperature ceramic atomizing core in the present invention has a high yield.

[0161] The above has made a detailed description of the embodiments of the present invention. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those of ordinary skill in the art, various changes can be made without departing from the gist of the present invention. In addition, without conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

Claims

1. A preparation method of modified diatomite, characterized in that: it comprises the following steps: mix and grind diatomite with an alcohol solvent, then mix and grind with a modifier, and then sinter at 1000 - 1300 °C to obtain the modified diatomite; the modifier includes at least one of a mixture of carbonate and aluminum oxide, silica sol, silicate, aluminate, and aluminosilicate; or, the modifier is a mixture that reacts at 1000 - 1300 °C to form silicate, aluminate or aluminosilicate; or, the modifier is a mixture that reacts at 1000 - 1300 °C to form silicon - oxygen bonds or silicon - aluminum bonds.

2. The preparation method of modified diatomite according to claim 1, characterized in that: the modifier includes at least one of a mixture of sodium carbonate and aluminum oxide, a mixture of potassium carbonate and aluminum oxide, sodium silicate, potassium silicate, calcium silicate, magnesium silicate, sodium aluminate, potassium aluminate, calcium aluminate, magnesium aluminate, sodium aluminosilicate, and potassium aluminosilicate; and / or, the alcohol solvent is selected from at least one of methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, propylene glycol, and glycerol.

3. A modified diatomite, characterized in that: it is prepared by the preparation method of claim 1 or 2.

4. A medium - low temperature ceramic atomizing core, characterized in that: it includes a heating element and an oil - guiding body, and the oil - guiding body includes the following preparation raw materials: the modified diatomite according to claim 3, glass powder, pore - forming agent, and additive; the preparation raw materials of the modified diatomite include diatomite and a modifier.

5. The medium - low temperature ceramic atomizing core according to claim 4, characterized in that: the oil - guiding body includes the following preparation raw materials by mass percentage: 10 - 50% of diatomite, 0 - 20% of ceramic powder, 5 - 20% of glass powder, 0.1 - 10% of modifier, 7 - 30% of pore - forming agent, and 10 - 30% of additive.

6. The medium - low temperature ceramic atomizing core according to claim 5, characterized in that: the ceramic powder is selected from at least one of quartz sand, silica powder, and kaolinite; and / or, the pore - forming agent is selected from at least one of flour, polymethyl methacrylate, and wood fiber; and / or, the glass powder includes the following preparation raw materials by mass percentage: 35 - 45% of silicon oxide, 20 - 25% of zinc oxide, 5 - 20% of boric acid, 2 - 10% of aluminum hydroxide, 5 - 10% of sodium oxide, 1 - 2% of titanium oxide, 0.5 - 1.5% of potassium oxide.

7. The medium - low temperature ceramic atomizing core according to claim 5, characterized in that: the additive is selected from at least one of paraffin, polyethylene, stearic acid, and oleic acid; preferably, based on the total mass percentage of the preparation raw materials of the oil - guiding body being 100%, the additive includes the following components by mass percentage: 8 - 20% of paraffin, 1 - 5% of polyethylene, 0.5 - 2% of stearic acid, and 0.5 - 3% of oleic acid.

8. The preparation method of the medium - low temperature ceramic atomizing core according to any one of claims 4 - 7, characterized in that: the preparation method includes the following steps: Step 1: Prepare molten liquids of modified diatomite, glass powder, and additive respectively; The preparation method of the modified diatomite is as follows: Mix and grind diatomite with an alcohol solvent, then mix and grind with a modifier, and then sinter at 1000-1300 °C to obtain the modified diatomite; Step 2: Mix and grind the preparation raw materials including modified diatomite, glass powder, and pore-forming agent, then mix with the additive melt, and then use a hot pressing or injection molding process to make the oil guiding body blank; Step 3: Debind and sinter the oil guiding body blank to obtain the oil guiding body; Step 4: Form a heating element on the oil guiding body by coating or printing to obtain the medium and low temperature ceramic atomization core; Or, the preparation method includes the following steps: Step 1: Prepare modified diatomite, glass powder, additive melt, and heating element respectively; Step 2: Mix and grind the preparation raw materials including modified diatomite, glass powder, and pore-forming agent, then mix with the additive melt to obtain a ceramic slurry, and then inject the ceramic slurry into a mold with a heating element placed inside to form a ceramic atomization core blank; Step 3: Debind and sinter the ceramic atomization core blank to obtain the medium and low temperature ceramic atomization core.

9. According to the preparation method of the medium and low temperature ceramic atomization core described in claim 8, it is characterized in that: The preparation method of the glass powder is as follows: Mix and grind the raw materials for preparing the glass powder, then calcine at 1400-1600 °C for 1.5-3 h, and then water quench to obtain the glass powder; and / or, the sintering temperature in Step 3 is 720-750 °C.

10. An electronic atomization device, it is characterized in that: It includes the medium and low temperature ceramic atomization core described in any one of claims 4-7.

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