Low-temperature atomized electronic cigarette tobacco tar and preparation method thereof

Abstract

The invention discloses low-temperature atomized electronic cigarette tobacco tar and a preparation method thereof. The tobacco tar comprises the following components in percentage by mass: 85%-98.5% of a solvent system, 0.5%-5% of nicotine salt, 0.5%-10% of a flavor substance and 0.1%-2% of a functional additive. The solvent system is composed of 20%-50% of plant glycerin, propylene glycol and a low-boiling-point cosolvent; wherein the low-boiling-point cosolvent accounts for 5-25% of the total mass of the solvent system. The nicotine salt is a salt formed by nicotine and organic acids such as malic acid; and a low-temperature flavor synergist is added into the flavor substance. The low-temperature atomization device is specially designed for low-temperature atomization at 180-240 DEG C, generation of harmful substances can be remarkably reduced, and meanwhile sufficient nicotine release efficiency, full flavor presentation and good atomization stability are guaranteed.

Description

Technical Field

[0001] This invention relates to the field of electronic cigarette technology, specifically to a low-temperature atomized electronic cigarette e-liquid and its preparation method. Background Technology

[0002] As one of the best-selling new tobacco products, e-cigarettes typically use e-liquids with a high proportion of vegetable glycerin (VG), usually exceeding 50%, to achieve large vapor production and a strong throat hit. These e-liquids are often combined with free nicotine or nicotine benzoate salts. Such traditional formulations require high operating temperatures (usually above 250°C) to achieve sufficient atomization. However, under high temperatures, components such as propylene glycol (PG), VG, and flavorings in the e-liquid are prone to thermal decomposition reactions, generating harmful carbonyl compounds such as formaldehyde, acetaldehyde, and acrolein, as well as various volatile organic compounds (VOCs), posing potential health risks to consumers.

[0003] To reduce the generation of harmful substances, the industry has begun exploring low-temperature atomization technology (operating temperature between 180-240℃). However, traditional high-VG e-liquids exhibit significant drawbacks in this low-temperature range: 1. Low atomization efficiency: VG has high viscosity and high boiling point, making it difficult to atomize fully at low temperatures, resulting in insufficient aerosol generation and a poor user experience.

[0004] 2. Insufficient nicotine release: Some nicotine salts (such as benzoates) do not completely dissociate at low temperatures, resulting in low nicotine delivery efficiency and poor physiological satisfaction for users.

[0005] 3. Distortion of flavor: Low temperature makes it difficult for many volatile "top aroma" flavor substances to be released effectively. At the same time, the thermal decomposition pathway of complex flavor molecules is changed, resulting in a blurred and unnatural overall flavor profile.

[0006] 4. Increased condensation: Incompletely atomized aerosol droplets are more likely to condense on cooled surfaces (such as mouthpieces and air passages), leading to liquid accumulation in the mouthpiece and waste of e-liquid, affecting the user experience and hygiene.

[0007] Existing solutions have limitations. For example, simply reducing the VG ratio can lead to a thin flavor and weak throat hit; or simply lowering the atomizer power without simultaneously optimizing the e-liquid formula can fail to systematically solve the core problem of low-temperature atomization.

[0008] Therefore, existing technologies struggle to simultaneously achieve the four goals of "sufficient aerosol," "efficient nicotine release," "full flavor presentation," and "low harmful substance generation" at low temperatures of 180-240℃. The market urgently needs to develop an innovative e-liquid specifically designed for low-temperature atomization environments, capable of synergistic optimization at the formulation level. Summary of the Invention

[0009] To address some or all of the problems existing in the prior art, the present invention provides a low-temperature atomizing e-cigarette e-liquid, comprising the following components by mass percentage: Solvent system: 85%-98.5%; Nicotine salts: 0.5%-5%; Flavor compounds: 0.5%-10%; Functional additives: 0.1%-2%.

[0010] As a further improvement of the present invention, the solvent system is composed of vegetable glycerin, propylene glycol, and a low-boiling-point co-solvent; wherein the vegetable glycerin accounts for 20%-50% by mass in the solvent system. The mass percentage of vegetable glycerin is significantly lower than that of traditional e-liquids, which ensures that the e-liquid has sufficient fluidity and a low boiling point at low temperatures.

[0011] As a further improvement of the present invention, the low-boiling-point co-solvent is selected from at least one of propylene glycol diacetate, propylene carbonate, and glyceryl triacetate, and the amount of the low-boiling-point co-solvent added is 5%-25% of the total mass of the solvent system. This low-boiling-point co-solvent has a boiling point between 150-220℃, exhibits excellent volatility within the target low-temperature range, and can effectively "carry" VG, PG, and other components for co-atomization, improving overall atomization efficiency and helping to reduce the surface tension of aerosol droplets, thus reducing the formation of condensate.

[0012] As a further improvement of the present invention, the nicotine salt is a salt formed by nicotine and an organic acid; the organic acid is selected from at least one of malic acid, tartaric acid, citric acid, and succinic acid. Compared with traditional benzoic acid nicotine salts, nicotine salts formed from these polyprotic organic acids exhibit superior dissociation kinetics within a target temperature window of 180-240°C. Their dissociation process can be better matched with the solvent evaporation and atomization processes, thereby achieving a nicotine release efficiency of not less than 85% at low temperatures (tested using an in vitro simulated smoking machine).

[0013] As a further improvement of the present invention, the molar ratio of nicotine to the organic acid is 1:1 to 1:1.5.

[0014] As a further improvement of the present invention, the flavor substances include a base flavoring agent and a low-temperature flavor enhancer; the low-temperature flavor enhancer is at least one of furanone, ethyl maltol, and 2-acetylpyrazine, and the amount of the low-temperature flavor enhancer added is 0.01%-0.5% of the total mass of the e-liquid. These low-temperature flavor enhancers themselves have low aroma thresholds and high intensity, and can be effectively volatilized at low temperatures. More importantly, they can synergistically work with the base flavoring agent to modify and enhance the overall flavor profile, making up for the deficiency of insufficient volatilization of some high-boiling-point flavor substances caused by low temperatures, so that the flavor performance under low-temperature atomization is still full and layered.

[0015] As a further improvement of the present invention, the functional additives include food-grade nonionic surfactants and / or antioxidants. Surfactants reduce the surface energy of aerosol droplets, making them more stable and less prone to condensation on the airway walls. Antioxidants prevent the e-liquid from oxidizing and deteriorating during storage and atomization.

[0016] As a further improvement of the present invention, the food-grade nonionic surfactant is polysorbate 80, and its addition amount is 0.05%-0.5% of the total mass of the e-liquid; the antioxidant is tocopherol, and its addition amount is 0.05%-0.2% of the total mass of the e-liquid.

[0017] On the other hand, the present invention also provides a method for preparing the above-mentioned low-temperature atomized electronic cigarette e-liquid, comprising the following steps: S1: Under room temperature and light-protected conditions, the nicotine salt is added to propylene glycol and stirred until completely dissolved to obtain the first solution; S2: Add vegetable glycerin and a low-boiling-point co-solvent to the first solution, stir until homogeneous, and obtain the second solution; S3: Add the flavor substance and the functional additive to the second solution, and stir until the system is homogeneous and transparent; S4: Allow the homogenized mixture obtained in step S3 to stand and age to obtain the low-temperature atomized e-cigarette oil.

[0018] As a further improvement of the present invention, in step S1, the stirring speed is 500 rpm and the stirring time is 30 minutes; in step S3, the stirring time is 2 hours; and in step S4, the settling and aging time is 24 hours.

[0019] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention, by controlling the VG ratio to below 50% and adding a low-boiling-point co-solvent, enables the e-liquid system to achieve full atomization at a relatively low temperature of 180-240℃, avoiding the thermal decomposition of components such as PG and VG caused by traditional high-temperature atomization. Actual measurements show that when the e-liquid of this invention is atomized at 200℃, the total release of harmful carbonyl compounds such as formaldehyde, acetaldehyde, and acrolein in the aerosol is reduced by more than 70% compared to traditional e-liquids of the same flavor atomized at 260℃, demonstrating a significant reduction in the production of harmful substances.

[0020] 2. This invention uses low-temperature atomized e-liquid, which reduces the thermal decomposition and transformation of flavor substances. Combined with specially formulated low-temperature flavor enhancers, it can more realistically and purely reproduce the designed flavor of the formula, resulting in a clear taste profile and a clean aftertaste, thus enhancing the user experience.

[0021] 3. This invention uses nicotine salts formed from poly-organic acids such as malic acid and tartaric acid. Their dissociation characteristics are highly matched with the low-temperature atomization process, so that the nicotine release efficiency can reach 85%-90% at 180-240℃, effectively ensuring the user's physiological satisfaction, and with a smooth taste and low irritation.

[0022] 4. The food-grade surfactants (such as polysorbate 80) added in this invention improve the stability of the aerosol and reduce the accumulation of condensate in the mouthpiece and airway; antioxidants (such as tocopherol) extend the storage stability of the e-liquid. The entire formulation system is specifically designed to match low-temperature atomization devices that use porous ceramic cores, precise temperature control chips, and other technologies, and has strong system adaptability. Detailed Implementation

[0023] Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention; the terms "comprising" and "having," and any variations thereof, in the specification and claims are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the specification and claims are used to distinguish different objects, not to describe a particular order.

[0024] In this invention, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment to other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this invention can be combined with other embodiments.

[0025] To enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below.

[0026] Example 1: A low-temperature atomizing e-cigarette liquid, comprising the following components by weight percentage: Nicotine malate 3%, vegetable glycerin (VG) 30%, propylene glycol (PG) 55%, propylene glycol diacetate (PGDA) 8%, tobacco flavoring 3.5%, furanone 0.1%, polysorbate 80 0.3%, tocopherol 0.1%.

[0027] The preparation method of the low-temperature atomized e-cigarette liquid in this embodiment is as follows: S1: At room temperature (25°C) and in the dark, first add nicotine malate to propylene glycol (PG) and stir magnetically at 500 rpm for 30 minutes until completely dissolved.

[0028] S2: Add vegetable glycerin (VG) and propylene glycol diacetate (PGDA) in sequence, and continue to stir until homogeneous.

[0029] S3: Then add tobacco flavoring, furanone, polysorbate 80, and tocopherol, and stir for 2 hours until the system is homogeneous and transparent.

[0030] S4: After the obtained mixture is left to stand and age for 24 hours, the low-temperature atomized electronic cigarette e-liquid is obtained.

[0031] Example 2: The only difference between this example and Example 1 is the raw material ratio: 40% vegetable glycerin (VG) and 45% propylene glycol (PG). The remaining composition and preparation method are exactly the same as in Example 1. The prepared e-cigarette oil was then tested, and the results are shown in Table 1.

[0032] Example 3: The components in this example are proportioned as follows by mass percentage: The e-liquid contained 3% nicotine malate, 25% vegetable glycerin (VG), 50% propylene glycol (PG), 10% propylene glycol diacetate (PGDA), 5% tobacco flavoring, 0.2% furanone, 0.3% polysorbate 80, and 0.5% tocopherol. The preparation method in this example was exactly the same as in Example 1. The prepared e-liquid was subsequently tested, and the results are shown in Table 1.

[0033] Comparative Example 1: A commercially available tobacco-flavored e-liquid was provided, comprising the following components by weight percentage: 3% nicotine benzoate, 70% vegetable glycerin (VG), and 27% propylene glycol (PG). This e-liquid does not contain low-boiling-point cosolvents or flavor enhancers. The e-liquid was used for subsequent testing, and the results are shown in Table 1.

[0034] Comparative Example 1: Another commercially available tobacco-flavored e-liquid was provided, which, by weight percentage, consisted of the following components: 3% nicotine benzoate, 55% vegetable glycerin (VG), and 42% propylene glycol (PG). This e-liquid did not contain low-boiling-point cosolvents or flavor enhancers. This e-liquid was used for subsequent testing, and the results are shown in Table 1.

[0035] Performance testing experiments: 1. Testing Methods The e-liquids were injected into identical ceramic-core pod-type smoking devices with precise temperature control. The device operating temperature was set to 200℃. A linear smoking machine conforming to ISO 20768:2018 standards was used for puffing (55 mL puff volume, 3 seconds duration, 30 puffs / frequency). The aerosol from the first 50 puffs was collected for subsequent analysis.

[0036] (1) Release of hazardous substances: The content of formaldehyde, acetaldehyde and acrolein in the aerosol capture liquid was quantitatively analyzed by GC-MS (Agilent 7890B / 5977B).

[0037] (2) Nicotine release efficiency: The nicotine content in the aerosol capture liquid was analyzed by HPLC (Waters Alliance) and the percentage of the total nicotine in the consumed e-liquid was calculated.

[0038] (3) Sensory evaluation: Five experienced tasters conducted the evaluation under single-blind conditions, scoring the flavor intensity, smoothness, and overall satisfaction (1-10 points, with 10 points being the best), and taking the average score.

[0039] Table 1: Performance test results of Examples 1-3 and Comparative Examples 1-2 Test Project Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Formaldehyde release (μg / puff) 0.8 1.0 0.7 5.5 3.8 Acetaldehyde release (μg / puff) 1.5 1.8 1.4 12.0 8.5 Acrolein release (μg / puff) 0.1 0.1 0.1 1.2 0.8 Total aldehyde release (μg / puff) 2.4 2.9 2.2 18.7 13.1 Compared to Comparative Example 1, it decreased 87.2% 84.5% 88.2% (Benchmark) 30.0% Nicotine release efficiency 88% 85% 90% 45% 60% Sensory rating (flavor intensity) 8.5 8.0 9.0 4.0 5.5 Sensory rating (overall satisfaction) 8.5 8.0 9.0 3.5 6.0 *Sensory evaluation mainly examines aroma intensity, flavor reproduction, smoothness of mouthfeel, and satisfaction.

[0040] 2. Analysis of Experimental Results (1) Significant harm reduction effect: When the total aldehyde release (2.2-2.9 μg / puff) of Examples 1-3 of the present invention was atomized at a low temperature of 200℃, the total aldehyde release was extremely low, which was as high as 84.5%-88.2% compared with Comparative Example 1 (18.7 μg / puff). This directly proves the synergistic advantage of the "low VG ratio + low boiling point co-solvent" system in suppressing low temperature cracking.

[0041] (2) High efficiency of low-temperature nicotine delivery: The nicotine release efficiency of the example reached 85%-90%, which is much higher than that of Comparative Example 1 (45%) and Comparative Example 2 (60%). This proves the good compatibility of malate nicotine salt with the low-temperature atomization system.

[0042] (3) Excellent sensory experience: The examples obtained high sensory scores, indicating that the e-liquid of the present invention can still provide a rich flavor and good satisfaction at low temperatures. In contrast, the traditional e-liquid in Comparative Example 1 had a poor vaping experience due to insufficient atomization.

[0043] (4) Demonstration of synergistic effects: Although the performance of Comparative Example 2 (VG 55%, no low-boiling-point co-solvent) was improved compared to Comparative Example 1, it was significantly inferior to the embodiments of the present invention in terms of harm reduction, nicotine efficiency, and sensory experience. This demonstrates that controlling the VG ratio below 50% and simultaneously adding a low-boiling-point co-solvent is necessary and synergistic for achieving the overall beneficial effects of the present invention, rather than a simple additive effect.

[0044] Example 4: This example provides a fruit-flavored low-temperature atomizing e-cigarette liquid, comprising, by weight percentage: 2.5% nicotine tartrate, 35% vegetable glycerin (VG), 50% propylene glycol (PG), 8% propylene carbonate (low-boiling point co-solvent), 4% mixed fruit flavoring, 0.2% ethyl maltol, 0.2% polysorbate 80, and 0.1% tocopherol. Its preparation method is similar to that of Example 1.

[0045] Following the above testing method, when atomized at 200℃, the expected total aldehyde release is less than 3.0 μg / puff, the nicotine release efficiency is higher than 86%, and the sensory score is excellent.

[0046] Example 5: This example provides a mint-flavored low-temperature atomizing e-cigarette liquid, comprising, by weight percentage: 4% nicotine citrate, 45% vegetable glycerin (VG), 40% propylene glycol (PG), 7% triacetin (low-boiling point co-solvent), 3.5% mint flavoring, 0.05% 2-acetylpyrazine, 0.4% polysorbate 80, and 0.05% tocopherol. Its preparation method is similar to that of Example 1.

[0047] Following the above testing method, when atomized at 200℃, the expected total aldehyde release is less than 3.5 μg / puff, the nicotine release efficiency is higher than 84%, and the sensory score is excellent.

[0048] The specific embodiments described above are preferred embodiments of the present invention and are not intended to limit the specific scope of the present invention. The scope of the present invention includes, but is not limited to, these specific embodiments. All equivalent changes made in accordance with the present invention are within the protection scope of the present invention.

Claims

1. A low temperature atomising e-liquid for an electronic cigarette, characterised in that, By mass percentage, the following components are included: Solvent system: 85%-98.5%; Nicotine salt: 0.5%-5%; Flavoring material: 0.5%-10%; Functional additive: 0.1%-2%.

2. The cryogenic atomised e-liquid of claim 1, wherein: The solvent system is composed of vegetable glycerin, propylene glycol and low-boiling co-solvent; wherein the mass percentage of the vegetable glycerin in the solvent system is 20%-50%.

3. The cryogenic atomized e-liquid of claim 1, wherein: The low-boiling co-solvent is selected from at least one of propylene glycol diacetate, propylene carbonate and glyceryl triacetate, and the added amount of the low-boiling co-solvent is 5%-25% of the total mass of the solvent system.

4. The cryogenic atomized e-liquid of claim 1, wherein: The nicotine salt is a salt formed by nicotine and an organic acid; the organic acid is selected from at least one of malic acid, tartaric acid, citric acid and succinic acid.

5. A cryogenic atomised e-liquid for an e-cigarette according to claim 4, wherein: The molar ratio of nicotine to the organic acid is 1:1 to 1:1.

5.

6. The cryogenic atomized e-liquid of claim 1, wherein: The flavoring material includes a base spice and a low-temperature flavor enhancer; the low-temperature flavor enhancer is at least one of furanone, ethyl maltol and 2-acetylpyrazine, and the added amount of the low-temperature flavor enhancer is 0.01%-0.5% of the total mass of the smoke oil.

7. The cryogenic atomized e-liquid of claim 1, wherein: The functional additive includes a food-grade non-ionic surfactant and / or an antioxidant.

8. A cryogenic atomised e-liquid for an e-cigarette according to claim 7, characterised in that: The food-grade non-ionic surfactant is polysorbate 80, and the added amount of polysorbate 80 is 0.05%-0.5% of the total mass of the smoke oil; The antioxidant is tocopherol, and the added amount of tocopherol is 0.05%-0.2% of the total mass of the smoke oil.

9. A method of producing the low temperature aerosol electronic cigarette liquid of any one of claims 2 to 8, characterised in that, The following steps are included: S1: under room temperature and light-proof conditions, the nicotine salt is added to propylene glycol, and stirred until completely dissolved to obtain a first solution; S2: vegetable glycerin and low-boiling co-solvent are added to the first solution, and stirred until uniform to obtain a second solution; S3: the flavoring material and the functional additive are added to the second solution, and stirred until the system is homogeneous and transparent; S4: the homogenized mixture obtained in step S3 is left to stand and age, thereby obtaining the low-temperature atomization electronic cigarette smoke oil.

10. A cryogenic atomised e-liquid for an e-cigarette according to claim 9, characterised in that: In step S1, the stirring speed is 500 rpm, and the stirring time is 30 minutes; in step S3, the stirring time is 2 hours; and in step S4, the standing and aging time is 24 hours.