Capsule and preparation method thereof

Abstract

The invention provides a capsule and a preparation method thereof, the capsule comprises a core material and a rubber sheet wrapping the core material, the core material comprises an aqueous liquid preparation, an oily preparation and a structuring agent; the structuring agent comprises cellulose and / or a cellulose derivative, a low-molecular-weight lipid and a surfactant; the core material is paste, colloid or a solid-liquid mixture, and the core material can realize that the aqueous liquid preparation is stably dispersed and fixed in the oily preparation, so that the core material is stably wrapped by the rubber skin. The invention also discloses an aerosol generating product using the capsule.

Description

Technical Field

[0001] This invention belongs to the field of material encapsulation technology, specifically relating to a capsule and its preparation method. Background Technology

[0002] As a core-shell structure, capsules provide excellent protection for their contents, preventing external environmental influences on their composition. Traditionally, capsule contents are oil-soluble, while the capsule membrane is water-soluble, with the oil-soluble contents encapsulated through a water-soluble membrane. However, when the contents contain aqueous components, the membrane fluid will dissolve, preventing proper encapsulation.

[0003] In existing technologies, various capsule technologies for encapsulating water-based formulations have been developed. Among them, the photocuring drop method is relatively mature. However, the capsule shell prepared by this method uses components such as plastics, resins, and rubbers, and the photocuring process requires photoinitiators and photosensitizers. The shells made from these materials are prone to leaving a strong plastic smell or special odor, especially when the capsule is used as an aerosol generation matrix. Under heating conditions, the shell can easily release unpleasant odors or even harmful substances, which is detrimental to the inhalation experience. In early technologies, there was also a water-in-oil drop method for preparing water-based capsules. However, in the water-in-oil preparation system, the shell uses waxy materials, which leads to high viscosity of the shell material, low drop yield, and the waxy shell is brittle and fragile, which is not conducive to industrial production and processing. At the same time, the contents are also prone to leakage, making it unsuitable for long-term storage. In the improved three-layer dripping technology, water-based capsules are prepared through an oil-in-water emulsion process, with an outermost layer of rubber coating. This technology results in an excessively thick rubber coating and a low proportion of water-soluble materials, making it difficult to burst during actual use, such as by squeezing. The release efficiency during heating is also relatively low. Furthermore, the preparation process is complex, and the core liquid can easily break through the middle layer and contact the outer water-soluble rubber coating, leading to uncontrollable yield rates. Additionally, long-term storage can cause slow leakage of the internal liquid. Another method is coagulation-based preparation, such as using polylactic acid to form a rubber coating through stirring and coagulation. Capsules prepared using this method have a wide particle size distribution and inconsistent shapes, generally making it difficult to produce perfectly spherical capsules. The capsule wall thickness distribution is also uneven, resulting in significant deviations in application, especially poor uniformity during heating and release. There is also a water-based capsule technology using sodium alginate as the rubber coating. Capsules obtained using this technology cannot be stored or used in a dry environment, especially when the core liquid is untreated, as the internal water-based formulation easily leaks out, making it impossible to dry the capsule.

[0004] While the aforementioned existing technologies provide methods for preparing capsules containing aqueous components, they all have various drawbacks. When the aqueous component is a liquid formulation such as glycerol or propylene glycol, especially when the content is relatively high, either stable encapsulation cannot be achieved, or the storage stability is poor, or there are off-odors, or the homogeneity is insufficient, making them unsuitable as aerosol generation matrices. Summary of the Invention

[0005] Based on the series of problems mentioned above regarding the effective and stable encapsulation of aqueous components in liquid formulations, the present invention provides the following technical solution:

[0006] A capsule comprising a core material and a rubber sheet encapsulating the core material, wherein the core material comprises: an aqueous liquid formulation, an oily formulation, and a structural agent; the structural agent comprises cellulose and / or cellulose derivatives, and further comprises low molecular weight lipids and surfactants, and the core material is a paste, a colloid, or a solid-liquid mixture.

[0007] Optionally, the surfactant has an HLB value of 2 to 10.

[0008] Optionally, the surfactant has an HLB value of 4 to 7.

[0009] Optionally, the aqueous liquid formulation accounts for 5 to 60 wt% of the core material.

[0010] Optionally, the aqueous liquid formulation accounts for 15 to 50 wt% of the core material.

[0011] Optionally, the oily preparation accounts for 20-80 wt% of the weight of the core material, and the structural agent accounts for 5-20 wt% of the weight of the core material.

[0012] Optionally, the cellulose and / or cellulose derivatives together with the low molecular weight lipids account for 70-95 wt% of the weight of the structural agent, and the surfactant accounts for 30-5 wt% of the weight of the structural agent.

[0013] Optionally, the weight ratio of the cellulose and / or cellulose derivatives to the low molecular weight lipids is 20:1 to 1:1.

[0014] Optionally, the viscosity of the cellulose and / or cellulose derivative is 1 to 300 mPa·s (viscosity of a 5wt% solution in 80wt% toluene and 20wt% ethanol), accounting for 1 to 10wt% of the core material weight.

[0015] Optionally, the cellulose and / or cellulose derivative is at least one of cellulose acetate, nitrocellulose and ethyl cellulose.

[0016] Optionally, the low molecular weight lipid is at least one of animal wax, plant wax, mineral wax, synthetic wax, lecithin and its derivatives, phytosterols and their esters, fatty acids and their esters, triglycerides and fatty alcohols.

[0017] Optionally, the low molecular weight lipid is insect wax, beeswax, palm wax, or β-sitosterol.

[0018] Optionally, the surfactant is at least one of anionic surfactants, cationic surfactants, nonionic surfactants, and amphoteric surfactants.

[0019] Optionally, the surfactant is a combination of at least one of glyceryl monooleate and Span with Tween.

[0020] Optionally, the oily preparation is at least one of animal oil, vegetable oil, and mineral oil.

[0021] Optionally, the rubber sheet includes a colloidal substance and a curing agent.

[0022] Optionally, the colloidal substance is at least one of animal glue, plant glue, starch and its modified starch products, and the curing agent is a polyol.

[0023] Optionally, the aqueous liquid formulation includes a fuming substance that can be released upon heating.

[0024] Optionally, the heat-released fuming substance includes at least one of propylene glycol and glycerol.

[0025] Optionally, the propylene glycol and glycerol account for 80-100 wt% of the total weight of the aqueous liquid formulation.

[0026] Optionally, the core material may further include 0.1 to 20 wt% nicotine and / or nicotine salts by weight of the core material.

[0027] Optionally, the core material may further include 0.1 to 20 wt% of flavoring and / or extracts; the extracts generally refer to plant and animal extracts, preferably plant extracts, and more preferably tobacco extracts.

[0028] Optionally, the weight ratio of propylene glycol to glycerol is 2:8 to 8:2.

[0029] Optionally, the particle size of the capsule product is 0.5 to 8 mm.

[0030] Optionally, the particle size of the capsule product is 1 to 3 mm.

[0031] Optionally, the thickness of the rubber sheet is 50–150 μm.

[0032] The application of one or more of the capsules in aerosol-generating products.

[0033] A method for preparing the capsule product described above includes the following steps:

[0034] The core material is prepared by mixing raw materials containing aqueous liquid formulations, oily formulations and structural agents;

[0035] A film-forming liquid is prepared from raw materials containing colloidal substances, curing agents, and water.

[0036] The capsule is prepared by coating the core material with the coating liquid.

[0037] Optionally, the capsule is prepared by dripping and drying the core material and film liquid using a concentric dropper.

[0038] An aerosol-generating article includes an aerosol-generating matrix, wherein the aerosol-generating matrix includes the capsules described above.

[0039] Optionally, the aerosol-generating product is a heat-non-combustible product; optionally, the capsule is used as an aerosol-generating matrix.

[0040] Optionally, the heating release temperature of the aerosol-generated product is greater than 150°C.

[0041] Optionally, the heating release temperature of the aerosol-generated product is 200-300℃.

[0042] The capsule is optional and is used to provide flavor.

[0043] This invention provides a capsule and its preparation method. The capsule includes a core material and a rubber coating encapsulating the core material. The core material comprises an aqueous liquid formulation, an oily formulation, and a structural agent. The structural agent includes cellulose and / or cellulose derivatives, as well as low molecular weight lipids and surfactants. The core material is a paste, a colloid, or a solid-liquid mixture. The core material enables the aqueous liquid formulation to be stably dispersed and fixed in the oily formulation, thereby achieving stable encapsulation of the core material by the rubber coating. This invention also discloses an aerosol-generating product using the above-described capsule, which enables low-temperature heating release when the capsule is used as an aerosol-generating matrix. Detailed Implementation

[0044] The capsule of this invention comprises a core material and a rubber sheet encapsulating the core material, wherein the core material comprises: an aqueous liquid formulation, an oily formulation, and a structural agent; the structural agent comprises cellulose and / or cellulose derivatives, low molecular weight lipids, and surfactants, and the core material is a paste, a colloid, or a solid-liquid mixture.

[0045] The capsule of this invention, through the combination of cellulose and / or cellulose derivatives and low molecular weight lipids, facilitates the formation of a network structure in the oily formulation that is conducive to the dispersion and fixation of the aqueous liquid formulation. The surfactant helps to form an oil film between the core material and the rubber layer, thereby facilitating the encapsulation of the core material by the rubber layer. The core material formed by the aqueous liquid formulation, the oily formulation, and the structuring agent is in the form of a paste, a colloid, or a solid-liquid mixture at room temperature (25°C), which is conducive to achieving stable encapsulation of the core material by the rubber layer.

[0046] In some embodiments of the present invention, the yield rate of the capsules is above 50%; in some embodiments, the yield rate is above 60%; in some embodiments, the yield rate is above 70%; in some embodiments, the yield rate is above 80%; in some embodiments, the yield rate is above 90%; in some embodiments, the yield rate is above 95%; and in some embodiments, the yield rate is 100%.

[0047] In some specific embodiments of the capsules of the present invention, the surfactant has an HLB value of 2 to 10, and more specifically, an HLB value of 4 to 7. This HLB value range is conducive to forming a core material in the form of a paste, colloid, or solid-liquid mixture, which can facilitate more stable encapsulation.

[0048] In some specific embodiments of the capsules of the present invention, the aqueous liquid formulation is water or a liquid formulation that can be uniformly dispersed in water molecules to form a solution, such as ethanol, glycerol, or propylene glycol, etc.

[0049] In some embodiments of the capsule of the present invention, the aqueous liquid formulation accounts for 5-60 wt% of the weight of the core material; in some embodiments, the aqueous liquid formulation accounts for 15-50 wt% of the weight of the core material; and in some embodiments, the aqueous liquid formulation accounts for 25-45 wt% of the weight of the core material. For example, it can be 25 wt%, 30 wt%, 35 wt%, 40 wt%, or 45 wt%, etc.

[0050] In some embodiments of the capsule of the present invention, the oily preparation accounts for 20-80 wt% of the weight of the core material, and in other embodiments, the oily preparation accounts for 30-60 wt% of the weight of the core material. For example, it can be 30 wt%, 35 wt%, 40 wt%, 45 wt%, 50 wt%, 55 wt%, or 60 wt%, etc.

[0051] In some embodiments of the capsule of the present invention, the structural agent accounts for 5 to 20 wt% of the weight of the core material, and in other embodiments, the structural agent accounts for 10 to 15 wt% of the weight of the core material. For example, it can be 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, or 15 wt%, etc.

[0052] In some embodiments of the capsule of the present invention, the cellulose and / or cellulose derivatives and low molecular weight lipids together account for 70-95 wt% of the weight of the structural agent, and the surfactant accounts for 30-5 wt% of the weight of the structural agent. In other embodiments, the cellulose and / or cellulose derivatives and low molecular weight lipids together account for 75 wt%, 80 wt%, 85 wt%, 90 wt% of the weight of the structural agent, etc.

[0053] In some specific embodiments of the capsules of the present invention, the weight ratio of cellulose and / or cellulose derivatives to low molecular weight lipids is 20:1 to 1:1, specifically, it can be 20:1, 18:1, 16:1, 14:1, 12:1, 10:1, 9:1, 8:1, 7:1, 6:1, 5:1, 4:1, 3:1, 2:1 or 1:1, etc.

[0054] In some specific embodiments of the capsules of this invention, the viscosity of the cellulose and / or cellulose derivative is 1–300 mPa·s, accounting for 1–10 wt% of the core material weight. This viscosity is defined as the viscosity in a solution containing 5 wt% cellulose and / or cellulose derivatives, using a mixed solution of 80 wt% toluene and 20 wt% ethanol (EtOH) as a solvent. If the proportion of cellulose and / or cellulose derivatives to the core material weight is too high, the core material will be too hard, making encapsulation difficult. If the proportion is too low, it is not conducive to the formation of a paste, colloid, or solid-liquid mixture. A viscosity greater than 300 mPa·s is not conducive to product drop forming. In some specific embodiments, the cellulose and / or cellulose derivative is at least one of cellulose acetate, nitrocellulose, and ethyl cellulose.

[0055] The capsules of this invention, in which the term "low molecular weight" refers to the low molecular weight lipids, are understood in the conventional sense of the art. In some specific embodiments, the low molecular weight lipids may be lipids with a number average molecular weight of less than 3000. In some specific embodiments, the low molecular weight lipids are at least one of animal waxes, plant waxes, mineral waxes, synthetic waxes, lecithin and its derivatives, phytosterols and their esters, fatty acids and their esters, triglycerides, and fatty alcohols. Specific examples of animal waxes include beeswax, insect wax, beeswax, or cetacean wax. Specific examples of plant waxes include palm wax, candelilla wax, rice wax, or sunflower wax. Specific examples of mineral waxes include paraffin wax, ceresin wax, or microcrystalline wax. Specific examples of synthetic waxes include mixtures of natural waxes and chemically synthesized resins, such as plastic wax. Specific examples of phytosterols and their esters, and fatty acids and their esters, include β-sitosterol or γ-sitosterol.

[0056] In some specific embodiments of the capsule of the present invention, the surfactant is at least one of anionic surfactants, cationic surfactants, nonionic surfactants, and amphoteric surfactants. Specific examples of the anionic surfactant include sodium lauryl sulfate, triethanolamine lauryl sulfate, ammonium lauryl sulfate, sodium dodecylbenzene sulfonate, sodium stearate, semi-cured sodium borate, semi-cured potassium borate, potassium stearate oleate, potassium castor oil, sodium alkylnaphthalene sulfonate, sodium dialkyl sulfosuccinate, sodium alkyl diphenyl ether disulfonate, diethanolamine alkyl phosphate, potassium alkyl phosphate, sodium polyoxyethylene alkyl sulfate, or sodium polyoxyethylene alkylphenyl ether sulfate, etc. Specific examples of the cationic surfactant include lauryltrimethylammonium chloride, stearyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, distearate dimethylammonium chloride, alkylphenyl dimethylammonium chloride, stearyl oleate, stearyl acetate, or stearic acid, etc. The nonionic surfactant may specifically be, for example, glycerol fatty acid esters, propylene glycol fatty acid esters, sorbitol fatty acid esters, polyoxyethylene sorbitol fatty acid esters, propylene fatty acid esters, glycerol fatty acid esters, monosaccharide fatty acid esters, polyoxyethylene sorbitol fatty acid esters, polyoxyethylene sorbitol tetraoleate, polyoxyethylene alkyl ethers, polyoxypropylene alkyl ethers, polyoxyethylene polyoxypropylene glycol, polyoxyethylene polyoxypropylene alkyl ethers, and organic esters of polyethylene glycol, such as polyethylene glycol fatty acid esters, polyoxyethylene glycol oil, and polyoxyethylene hydrogenated castor oil. In some specific embodiments, the nonionic surfactant is selected from sorbitol fatty acid esters, polyoxyethylene sorbitol fatty acid esters, or polyoxyethylene sorbitol fatty acid esters. The amphoteric surfactant may specifically be, for example, alkyl dimethylaminoacetic acid betaine, alkyl dimethylamine oxide, alkyl carboxymethyl hydroxyethyl imidazolium betaine, lecithin, lauryl aminopropionic acid, or alkyl diaminoethyl glycine, etc.

[0057] In some specific embodiments of the capsule of the present invention, the surfactant is a combination of at least one of glyceryl monooleate and Span with Tween, having the HLB value. For example, a combination of Tween 80 and glyceryl monooleate, a combination of Tween 20 and glyceryl monooleate, a combination of Tween 80 and Span 80, a combination of Tween 20 and Span 80, etc.

[0058] In some specific embodiments of the capsules of the present invention, the oily preparation is at least one of animal oil, vegetable oil and mineral oil. The animal oil may be, for example, tallow or lard. The vegetable oil may be, for example, soybean oil, olive oil, corn oil, safflower oil, wheat germ oil or sunflower seed oil. The mineral oil may be, for example, silicone oil or white oil.

[0059] In some embodiments of the capsule of the present invention, the core material further includes 0.1–20 wt% of flavoring and / or extracts, and in other embodiments, the core material further includes 3–10 wt% of flavoring and / or extracts. The flavoring includes oil-soluble or water-soluble flavorings, and may be, for example, fruit-flavored flavorings such as lemon, mango, or sweet orange. The extracts generally refer to plant and animal extracts, such as musk and ambergris, preferably plant extracts such as tea extract and monk fruit extract, and more preferably tobacco extracts such as tobacco water extract, tobacco alcohol extract, and tobacco distillation products.

[0060] In some specific embodiments of the capsule of the present invention, the outer shell comprises a colloidal substance and a curing agent.

[0061] In some specific embodiments of the capsule of the present invention, the colloidal substance is at least one of animal glue, plant glue, and starch and its modified forms. The animal glue may be, for example, gelatin, fish glue, or chitosan, and the plant glue may be, for example, carrageenan, sodium alginate, gellan gum, or tamarind gum.

[0062] In some specific embodiments of the capsule of the present invention, the curing agent is a polyol, such as glycerol or sorbitol.

[0063] In some embodiments of the capsule of the present invention, the capsule shell further includes a reinforcing agent. In some embodiments, the reinforcing agent is a metal salt, such as calcium chloride, potassium chloride, calcium carbonate, calcium phosphate, or calcium dihydrogen phosphate.

[0064] In some specific embodiments of the capsule of the present invention, the capsule shell further includes a sweetener, such as mogroside, sucralose, or xylitol.

[0065] In some specific embodiments, the capsule product is a capsule product for use as a medicine, food, or cosmetic.

[0066] In some embodiments of the capsule of the present invention, the aqueous liquid formulation includes an aerosol-generating aqueous liquid formulation, and the capsule can serve as an aerosol-generating matrix. In some embodiments, the aerosol-generating aqueous liquid formulation includes a heat-released fuming substance. In some embodiments, the heat-released fuming substance is at least one of propylene glycol and glycerol. In some embodiments, the propylene glycol and glycerol account for more than 80 wt% of the total weight of the aqueous liquid formulation. In some embodiments, the propylene glycol and glycerol account for more than 85 wt% of the total weight of the aqueous liquid formulation. In some embodiments, the propylene glycol and glycerol account for more than 90 wt% of the total weight of the aqueous liquid formulation. In some embodiments, the propylene glycol and glycerol account for more than 95 wt% of the total weight of the aqueous liquid formulation. In some embodiments, the propylene glycol and glycerol account for more than 100 wt% of the total weight of the aqueous liquid formulation.

[0067] In some specific embodiments of the capsule of the present invention, the core material further includes 0.1 to 20 wt% nicotine and / or nicotine salts, specifically, the content of nicotine and / or nicotine salts is 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 7 wt%, 9 wt%, 10 wt%, 12 wt%, 14 wt%, or 16 wt% of the core material, etc.

[0068] In the capsule of this invention, considering that a higher propylene glycol content in the core material results in a higher nicotine carryover, and a higher glycerol content increases the average aerosol particle size, leading to a better visual effect, the design aims to ensure both the amount of smoke and the amount of nicotine carryover, as well as the visual effect of the aerosol. Since cigarette consumers need both the pleasure of nicotine and the visual appeal of smoke, in some specific embodiments, the weight ratio of propylene glycol to glycerol is 2:8 to 8:2, specifically, for example, 2:8, 3:7, 4:6, 5:5, 6:4, 7:3, or 8:2, etc.

[0069] In some embodiments of the present invention, considering the aerosol release effect, the particle size of the capsule is 0.5-8 mm, and in other embodiments, the particle size of the capsule product is 1-3 mm, specifically, for example, 1 mm, 1.5 mm, 2 mm, 2.5 mm or 3 mm, etc.

[0070] In some specific embodiments of the capsule of the present invention, considering the influence of the thickness of the rubber shell on the capsule strength and aerosol release, the thickness of the rubber shell is 50-150 μm, specifically for example, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm or 150 μm, etc.

[0071] Specific embodiments of the present invention also provide the application of the above-described capsules in aerosol-generating products. The capsules can provide flavor and can also be used as an aerosol-generating matrix. When the capsules are used as an aerosol-generating matrix in the aerosol-generating product, the capsules include a core material and a rubber sheet encasing the core material. The core material includes at least one of propylene glycol and glycerol. Although existing heated tobacco products use reconstituted tobacco leaves or shredded tobacco with added glycerin and / or propylene glycol as smoke-generating agents, producing smoke at a relatively low heating temperature (<350°C) to achieve a smoking effect, these heated tobacco products release fewer harmful substances. However, the actual heating temperature is significantly lower than that of traditional tobacco. To solve the problem of releasing sufficient smoke at a lower temperature, the amount of glycerin and propylene glycol must be increased. However, glycerin and propylene glycol themselves have good hygroscopicity, resulting in high hygroscopicity of the product, which brings great inconvenience to subsequent processing and storage. Furthermore, after opening the packaging, the protection of the cigarettes cannot be guaranteed, resulting in uneven smoking of different cigarettes. Furthermore, heat transfer requires a time process, and the amount of smoke produced by the same cigarette varies over time. The aerosol-generating product of this invention, by preparing propylene glycol and / or glycerol as a core material and then encapsulating it in a rubber shell, serves as the smoke-generating material for the cigarette. This overcomes the aforementioned problems of existing heat-not-burn cigarettes and can further reduce the heating temperature and harmful substances. In some specific embodiments, the heating release temperature of the aerosol-generating product is greater than 150°C; in other specific embodiments, the heating release temperature is 200-300°C; specifically, the heating release temperature can be, for example, 200°C, 210°C, 220°C, 230°C, 240°C, 250°C, 260°C, 270°C, 280°C, or 290°C, etc. In some specific embodiments, the aerosol-generating product includes a capsule containing at least one of propylene glycol and glycerol.

[0072] A specific embodiment of the present invention also provides a method for preparing the capsules described above, comprising the following steps:

[0073] The core material is prepared by mixing raw materials containing aqueous liquid formulations, oily formulations and structural agents;

[0074] A film-forming liquid is prepared from raw materials containing colloidal substances, curing agents, and water.

[0075] The capsule is prepared by coating the core material with the coating liquid.

[0076] In some specific embodiments of the present invention, the preparation method of the capsule involves heating the oily preparation to 90°C to 150°C, adding the cellulose and / or cellulose derivatives and low molecular weight lipids while stirring, dissolving and mixing evenly, cooling to 50°C to 80°C, adding the aqueous liquid preparation and surfactant, stirring evenly, and preparing the core material.

[0077] In some specific embodiments of the capsule preparation method of the present invention, the core material is a paste, colloid or solid-liquid mixture at room temperature (25°C) and does not separate into layers after being placed at room temperature for 10 hours.

[0078] In some specific embodiments of the present invention, the preparation method of the capsule involves adding the colloidal substance into purified water, stirring and heating at a temperature of 60-90°C to form a uniform solution, adding a curing agent, or a curing agent, reinforcing agent, sweetener, etc., and stirring evenly to prepare the film liquid.

[0079] The capsule preparation method of this invention, wherein the capsule is prepared by coating the core material with the coating solution, can employ existing encapsulation methods. In some specific embodiments, the method is a concentric tube dripping method, in which the core material and coating solution are dripped and dried through a concentric dropper to prepare the capsule. The core material is introduced through an inner tube, and the coating solution is introduced through an outer tube. Different film thicknesses can be formed by adjusting the amount of coating solution added.

[0080] The present invention will be further illustrated by specific embodiments below.

[0081] Test instructions:

[0082] Core material state at room temperature: Add the core material to a 100ml test tube and leave it at room temperature for 4 hours, then observe the state of the core material.

[0083] Stability: Add the core material to a 100ml test tube and leave it at room temperature. If it does not separate into layers after more than 10 hours, it is considered good; if it separates into layers after 6 to 10 hours, it is considered relatively good; if it separates into layers after less than 6 hours, it is considered poor.

[0084] Particle size: The diameter of 30 capsules was measured using a vernier caliper, and the average diameter was taken.

[0085] Yield: Observe the positional relationship between the core material and the rubber sheet using a magnifying glass. Ideally, the core material should be in the exact center of the rubber sheet, with the rubber sheet completely covering the core material and maintaining a minimum thickness of 50μm. If the core material deviates from the exact center of the rubber sheet, resulting in a thickness of less than 10μm at some point around the core material, or if the core material punctures the rubber sheet, preventing the rubber sheet from completely covering the core material, then the capsule is considered defective. Observe the rubber sheet coverage of 100 capsules using a magnifying glass and calculate the yield. A yield of over 90% indicates a high yield, while a yield of less than 50% indicates a low yield.

[0086] Wall thickness: The thickness is calculated by dividing the center of the capsule product into two parts and measuring four points to obtain the average value of the left, right, top, and bottom.

[0087] Volatilization calculation:

[0088]

[0089] Ma: Weight of the capsule product; Mb: Weight of the capsule product after heating.

[0090] Nicotine content: The capsules were filled into paper tubes, placed in a low-temperature smoking device, and smoked using a smoking machine with a 15-second interval between puffs and 2 seconds per puff, for a total of 15 puffs. The filter was then collected, and the nicotine content was measured.

[0091] Example

[0092] Example 1

[0093] 40 parts by weight of sunflower seed oil were heated to 100°C. While stirring, cellulose and / or cellulose derivatives and low molecular weight lipids (total structural agent 13 parts by weight, Table 1 shows the weight ratio of cellulose and / or cellulose derivatives, low molecular weight lipids and surfactants) were added and dissolved until homogeneous. The mixture was then cooled to 60°C. 24 parts by weight of propylene glycol, 16 parts by weight of glycerol, surfactants from Table 1, 5 parts by weight of mango flavoring, and 2 parts by weight of nicotine salt were added and stirred until homogeneous to complete the core material preparation. The core material was observed at room temperature and its stability was assessed. The results are shown in Table 1 below.

[0094] Table 1. Capsules prepared with different structuring agent formulations and test results.

[0095]

[0096]

[0097] Continued from Table 1

[0098]

[0099] As shown in Table 1 above, the core material formed by combining cellulose and / or cellulose derivatives with low molecular weight lipids, and a surfactant with an HLB value between 2 and 10, especially between 4 and 7, with a high content of aqueous propylene glycol / glycerol in oily sunflower oil, is a colloid at room temperature and has good stability, resulting in a high yield of capsules.

[0100] Based on formulations 11 and 12 in Table 1, it can be seen that the yield rate is low when the structural agent does not contain cellulose and / or cellulose derivatives or low molecular weight lipids; in addition, in the comparative experiment, the yield rate is also low if the structural agent does not contain surfactants.

[0101] Example 2

[0102] Heat 40 parts by weight of sunflower seed oil to 100°C, add the raw materials according to the ratio of formula 7 in Table 1, dissolve and mix evenly, cool to 60°C, add 40 parts by weight of propylene glycol and glycerol (PG / VG) as shown in Table 2, 5 parts by weight of mango flavoring, and 2 parts by weight of nicotine salt, stir evenly to complete the preparation of the core material.

[0103] Add 5 parts by weight of carrageenan and 3 parts by weight of gellan gum to 82 parts by weight of purified water, and heat while stirring at a temperature of 60-90°C to form a homogeneous solution. Add 10 parts by weight of glycerol and stir until homogeneous to prepare the film solution.

[0104] Using a concentric dropper, the core material (inner layer) and film liquid are dripped into the cooling liquid (MCT) while the temperature is controlled at 10℃~25℃ to form wet capsules. The capsules are then stored at -10℃~10℃ for 10 hours and dried at 20~30℃ and 20%~50% humidity to obtain capsule products with a particle size of 2mm and a wall thickness of 70μm.

[0105] The capsules were filled into paper tubes and placed in a low-temperature smoke heater for heating and inhalation. The inhalation interval was 15 seconds, with each puff lasting 2 seconds, for a total of 15 puffs. Different heating temperatures were achieved by adjusting the heater settings. The volatilization amounts of different propylene glycol (PG) / glycerol (VG) ratios at different temperatures are shown in Table 2 below.

[0106] Table 2 Comparison of the volatilization amounts of different propylene glycol (PG) / glycerol (VG) ratios at different temperatures.

[0107]

[0108] As shown in Table 2 above, the volatilization of aerosols increases with increasing heating temperature. The volatilization rate is similar between 220℃ and 300℃, indicating that at lower inhalation temperatures (220-260℃), the volatilization rate is essentially the same. The volatilization rate decreases with increasing glycerol content; however, at inhalation temperatures of 220-260℃, when the glycerol content is below 60 wt%, the volatilization rate can remain above 30%. Further analysis was conducted on the nicotine content of smoke generated from aerosol products (all including 0.22g capsules) made from capsules with different propylene glycol (PG) / glycerol (VG) ratios at 240℃ after inhalation. The results are shown in Table 3 below.

[0109] Table 3. Nicotine content in smoke at 240℃ for different propylene glycol (PG) / glycerol (VG) ratios.

[0110] PG / VG ratio 100 / 0 80 / 20 60 / 40 40 / 60 20 / 80 0 / 100 Nicotine content (mg) 3.8 2.94 2.28 1.76 1.37 1.05

[0111] As shown in Table 3 above, the higher the propylene glycol content, the higher the nicotine carryover. A propylene glycol content above 40 wt% maintains a relatively high nicotine carryover rate. Furthermore, according to known technologies, the higher the glycerol content, the better the visual effect of the aerosol. Considering the aerogel's evaporation rate, nicotine carryover, and visual effect, a propylene glycol to glycerol ratio between 2:8 and 8:2, especially between 4:6 and 6:4, yields the best results.

[0112] Example 3

[0113] Except for particle size, other conditions were the same as in Example 2. Capsule products with particle sizes of 1 mm, 2 mm, 3 mm, 4 mm and 5 mm were prepared. The volatilization of different propylene glycol (PG) / glycerol (VG) at a heating temperature of 240°C was tested, and the results are listed in Table 4 below.

[0114] Table 4 Comparison of volatile matter content of propylene glycol (PG) / glycerol (VG) with different particle sizes

[0115]

[0116] As shown in Table 4 above, when the particle size of the capsule products is between 1 and 3 mm and the ratio of propylene glycol to glycerol is different, the amount of volatilization is similar. As the particle size increases, the amount of aerosol generated decreases. If the particle size is too small, the content of propylene glycol and glycerol encapsulated is low, and the amount of aerosol generated is also low.

[0117] Example 4

[0118] Except for particle size and wall thickness, other conditions were the same as in Example 2. Capsules with a particle size of 2.5 mm and different wall thicknesses and different propylene glycol (PG) / glycerol (VG) were prepared, as shown in Table 5 below. The volatilization amount was tested at a heating temperature of 240°C and the capsule strength was judged. The results are listed in Table 5 below.

[0119] Table 5 Comparison of volatile matter and capsule strength for different wall thicknesses and propylene glycol (PG) / glycerol (VG) ratios

[0120]

[0121] As shown in Table 5 above, although capsules with a wall thickness of less than 50 μm have good smoke production, they are fragile and prone to breakage during the filling process into paper tubes, making them difficult to preserve. Capsules with a wall thickness of more than 150 μm are less prone to breakage during heating and produce less smoke.

[0122] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A capsule, characterized in that, The invention includes a core material and a rubber sheet encapsulating the core material, wherein the core material comprises: an aqueous liquid formulation, an oily formulation, and a structural agent; the structural agent comprises cellulose and / or cellulose derivatives, and the structural agent further comprises low molecular weight lipids and surfactants; the core material is a paste, a colloid, or a solid-liquid mixture.

2. The capsule according to claim 1, characterized in that, The surfactant has an HLB value of 2 to 10.

3. The capsule according to claim 2, characterized in that, The surfactant has an HLB value of 4 to 7.

4. The capsule according to claim 1, characterized in that, The aqueous liquid formulation accounts for 5 to 60 wt% of the core material.

5. The capsule according to claim 4, characterized in that, The aqueous liquid formulation accounts for 15 to 50 wt% of the core material.

6. The capsule according to claim 1, characterized in that, The oily preparation accounts for 20-80 wt% of the weight of the core material, and the structural agent accounts for 5-20 wt% of the weight of the core material.

7. The capsule according to claim 1, characterized in that, The cellulose and / or cellulose derivatives together with the low molecular weight lipids account for 70-95 wt% of the weight of the structural agent, and the surfactant accounts for 30-5 wt% of the weight of the structural agent.

8. The capsule according to claim 1, characterized in that, The weight ratio of the cellulose and / or cellulose derivatives to the low molecular weight lipids is 20:1 to 1:

1.

9. The capsule according to claim 1, characterized in that, The viscosity of the cellulose and / or cellulose derivatives is 1–300 mPa·s, and accounts for 1–10 wt% of the core material.

10. The capsule according to claim 1, characterized in that, The cellulose and / or cellulose derivatives are at least one of cellulose acetate, nitrocellulose and ethyl cellulose.

11. The capsule according to claim 1, characterized in that, The low molecular weight lipid is at least one of animal wax, plant wax, mineral wax, synthetic wax, lecithin and its derivatives, phytosterols and their esters, fatty acids and their esters, triglycerides and fatty alcohols.

12. The capsule according to claim 1, characterized in that, The surfactant is at least one of anionic surfactants, cationic surfactants, nonionic surfactants, and amphoteric surfactants.

13. The capsule according to claim 1, characterized in that, The oily preparation is at least one of animal oil, vegetable oil, and mineral oil.

14. The capsule according to claim 1, characterized in that, The rubber sheet includes a colloidal substance and a curing agent.

15. The capsule according to claim 14, characterized in that, The colloidal substance is at least one of animal glue, plant glue, starch, and starch-modified products, and the curing agent is a polyol.

16. The capsule according to claim 1, characterized in that, The aqueous liquid formulation includes a fuming substance that can be released upon heating.

17. The capsule according to claim 16, characterized in that, The heat-released fuming substance includes at least one of propylene glycol and glycerol.

18. The capsule according to claim 17, characterized in that, The propylene glycol and glycerol comprise 80-100 wt% of the total weight of the aqueous liquid formulation.

19. The capsule according to claim 16, characterized in that, The core material also includes 0.1 to 20 wt% nicotine and / or nicotine salts by weight of the core material.

20. The capsule according to claim 16, characterized in that, The core material also includes 0.1 to 20 wt% of fragrance and / or extracts by weight of the core material.

21. The capsule according to claim 17, characterized in that, The weight ratio of propylene glycol to glycerol is 2:8 to 8:

2.

22. The capsule according to claim 1, characterized in that, The capsules have a particle size of 0.5–8 mm.

23. The capsule according to claim 22, characterized in that, The capsules have a particle size of 1–3 mm.

24. The capsule according to claim 1, characterized in that, The thickness of the rubber sheet is 50–150 μm.

25. The use of the capsule according to any one of claims 1 to 24 in aerosol-generating articles.

26. A method for preparing a capsule according to any one of claims 1 to 24, characterized in that, Includes the following steps: The core material is prepared by mixing raw materials containing aqueous liquid formulations, oily formulations and structural agents; A film-forming liquid is prepared from raw materials containing colloidal substances, curing agents, and water. The capsule is prepared by coating the core material with the coating liquid.

27. The method for preparing the capsule according to claim 26, characterized in that, The capsule is prepared by dripping and drying the core material and film solution using a concentric dropper.

28. An aerosol-generating article comprising an aerosol-generating matrix, wherein the aerosol-generating matrix comprises the capsule as described in any one of claims 16 to 21.

29. The aerosol-generating article according to claim 28, characterized in that, The heating release temperature of the aerosol-generated product is greater than 150°C.

30. The aerosol-generating article according to claim 29, characterized in that, The heating release temperature of the aerosol-generated product is 200-300℃.

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