COMBUSTION-FREE CIGARETTE

Abstract

A combustion-free cigarette includes a sleeve, to the inner casing of which a nicotine solution is applied, in which it is proposed according to the invention that the sleeve is closed at one of its two ends by a partially air-tight draw-in brake and the nicotine solution consists of an amount of 0.8-1.2 mg of nicotine dissolved in 75-105 l of ethanol, the nicotine solution being applied as an at least partial wetting of the inner casing. The combustion-free cigarette reproduces the properties of a conventional cigarette in its dispensing of nicotine by the nicotine being absorbed in a sufficient quantity from the air flow arising within the sleeve during the customary draw-in process and being available for inhaling.

Claims

1. A combustion-free cigarette comprising: a sleeve, to the inner casing of which a nicotine solution is applied, wherein the sleeve is closed at one of its two ends by a partially air-tight draw-in brake and the nicotine solution consists of an amount of 0.8-1.2 mg of nicotine dissolved in 75-105 l of ethanol, the nicotine solution being applied as an at least partial wetting of the inner casing.

2. The combustion-free cigarette according to claim 1, wherein the nicotine solution comprises an amount of 1 mg nicotine dissolved in 100 l ethanol.

3. The combustion-free cigarette according to claim 1, wherein the nicotine solution is applied as an at least partial wetting of the inner casing with a maximum contact angle of 75.

4. The combustion-free cigarette according to claim 1, wherein the sleeve is made of bagasse.

5. The combustion-free cigarette according to claim 1, wherein the sleeve is made of glass, the inner casing being roughened to ensure a contact angle of a maximum of 90.

6. The combustion-free cigarette according to claim 1, wherein the sleeve is made of a plastic that can be applied using an FFF (Fused Filament Fabrication) manufacturing process.

7. The combustion-free cigarette according to claim 1, wherein the inner casing that is at least partially wetted by the nicotine solution has a surface area of 500-2000 mm.sup.2.

8. The combustion-free cigarette according to claim 7, wherein the inner casing which is at least partially wetted by the nicotine solution has a surface area of 1000 mm.sup.2.

9. The combustion-free cigarette according to claim 1, wherein the sleeve is cylindrical and has a length of 50-100 mm and an inner diameter of 3-6 mm.

10. The combustion-free cigarette according to claim 1, wherein flavorings are added to the nicotine solution.

11. The combustion-free cigarette according to claim 1, wherein the nicotine used for the nicotine solution has a pH value in the basic range.

12. A combustion-free cigarette consisting of a sleeve, to the inner casing of which a nicotine solution is applied, wherein the sleeve is closed at one of its two ends by a partially air-tight draw-in brake and the nicotine solution consists of an amount of 0.8-1.2 mg of nicotine dissolved in 75-105 l of ethanol, the nicotine solution being applied as an at least partial wetting of the inner casing.

13. The combustion-free cigarette according to claim 1, wherein the nicotine solution consists of an amount of 1 mg nicotine dissolved in 100 l ethanol.

Description

[0020] The invention is explained in more detail below using exemplary embodiments with the help of the accompanying figures. Here, the

[0021] FIG. 1 shows a schematic view of an embodiment of a cigarette according to the invention,

[0022] FIG. 2 shows experimental results on the cumulative amount of nicotine in g absorbed by an air stream within a sleeve over the number of simulated puffs, whereby the sleeve is made of a PETG that can be applied using an FFF (Fused Filament Fabrication) manufacturing process,

[0023] FIG. 3 shows experimental results on the cumulative amount of ethanol (uncalibrated) absorbed by an air stream within a sleeve according to FIG. 2 over the number of simulated puffs, and

[0024] FIG. 4 shows experimental results on the cumulative amount of nicotine in g absorbed by an air stream within a sleeve over the number of simulated puffs, whereby the sleeve is made of glass, the inner casing of which is roughened to ensure a contact angle of a maximum of 90.

[0025] First, reference is made to FIG. 1, which shows a schematic view of an embodiment of a cigarette according to the invention. The cigarette according to the invention is similar in its dimensions to a conventional tobacco cigarette and has a cylindrical sleeve 1 with a length of 50-100 mm and an inner diameter of 3-6 mm. The inner casing 1a of the sleeve 1 has a surface area of 500-2000 mm.sup.2, preferably a surface area of 1000 mm.sup.2. The outer casing 1b of the sleeve 1 can be colored with food-safe color to give the sleeve 1 a white color, for example. The wall thickness of the sleeve 1 is 1.5 mm to 2.5 mm, preferably 1.5 mm, so that there is sufficient strength to prevent the chemicals from diffusing through the wall.

[0026] At its first end, the sleeve 1 is closed with a partially airtight draw-in brake 2, which is designed, for example, as a conventional cigarette filter. The draw-in brake 2 represents an intake resistance that reduces the air flow speed within the sleeve 1, so that the contact time between the air flow and the inner casing 1a is increased. In addition, the smoker is offered the usual intake resistance. The air sucked in enters the interior of the sleeve 1 via the opening at the opposite, second end of the sleeve 1, passes in an axial direction through the interior of the sleeve 1 in the direction of the draw-in brake 2 and through the draw-in brake 2 until it leaves the cigarette according to the invention at the free end of the draw-in brake. Alternatively, the draw-in brake 2 can also be designed as a solid, cylindrical intake plug with a conical channel made of biodegradable plastic, which has a conical air channel inside that tapers towards the intake opening and is open at both ends.

[0027] The open, second end of the cigarette according to the invention can be closed with a sealing film to prevent the nicotine solution from escaping during storage. Such a sealing film would have to be removed before use. The applicants, however, have determined that the closure of the second, open end of the cigarette can also be omitted because the escape of evaporated nicotine solution is negligible under the given geometric conditions, especially when cigarettes according to the invention are stored sealed in an airtight package. The air exchange between the sleeve 1, which is sealed on one side, and the environment is obviously sufficiently low so that saturation of evaporated nicotine solution quickly occurs within the sleeve 1, which prevents further evaporation of the nicotine solution.

[0028] A quantity of 75-105 l of ethanol, which is mixed with a quantity of 0.8-1.2 mg of nicotine, is applied to the surface of the inner casing la. The nicotine solution can be applied to the inner casing 1a using a dosing and spray needle, which has a large number of holes or nozzles along its axial length. With such a dosing and spray needle, it is possible to wet the entire inner casing 1a of the sleeve 1 with the nicotine solution with one spray.

[0029] The following investigations have shown that the applied nicotine is sufficiently mobilized and carried away by a periodic air stream, as corresponds to typical smoking behavior.

Experimental Evidence

[0030] First, the co-evaporation of nicotine and ethanol was demonstrated and quantified using a nicotine solution of 1 mg nicotine in 100 l ethanol. The evaporation should take place in a process that corresponds to typical smoking behavior. To do this, a smoker was asked to suck on a sleeve that was connected to a measuring cylinder, just as he would suck on a cigarette. This experiment was repeated with a female smoker. Both people repeated the process at least five times. It was shown that typical puffs taken by these people had volumes of around 40-80 ml. Questioning the people showed that they had around 10-40 seconds between puffs on a normal cigarette.

[0031] In order to be able to reproduce this smoking behavior in a reproducible manner for laboratory tests, a measurement setup was developed in which air was cyclically sucked through a tube whose dimensions corresponded to a cigarette according to the invention and whose inner casing 1a was wetted with a 100 l ethanol-nicotine mixture with 1 mg/100 l nicotine, whereby the exhalation did not take place through the tube. These tubes, which are filled with a nicotine-ethanol mixture, are referred to below as evaporator tubes. In a first experiment, the evaporator tubes were made from PETG using an FFF (Fused Filament Fabrication) manufacturing process. These evaporator tubes were manufactured using a commercially available Ultimaker 2+ 3D printer with a needle tip of 0.25 mm. The layer thickness of the applied plastic layers was between 60-150 m.

[0032] The measurement setup also allowed a variable time period between puffs to be programmed as a break using a microcontroller that controlled the setup. Suction was carried out using two 50 ml syringes connected in parallel, which were driven by a linear motor. A switching valve allowed air to be sucked out of the evaporator tube through an adsorber tube (Tenax tube) and an alcohol sensor as well as a UV sensor. The switching valve switched off the path through the tubes and allowed the syringes to be emptied into the ambient air,

[0033] The adsorber tubes were filled with Tenax. Tenax is the brand name of poly(2, 6-diphenyl-p-phenylene oxide), a polymer adsorber resin that is used as a column packing material for gas chromatography, since substances such as nicotine adsorb almost completely to the resin when the amount of substance is significantly below the binding capacity. The substances can then be desorbed by heating and fed to a mass spectrometer in the gas phase for further analysis. The Tenax tubes (17.8 cm) were analyzed using a Gerstel TDS 3 with a TDS A2 autosampler, typically using a split of 20:1 or 5:1. The molecules to be analyzed are transferred to the gas phase (desorption) and ionized by heating in an inert gas atmosphere at negative pressure. The ions are then accelerated by an electric field and fed to an analyzer, which separates them according to their mass-to-charge ratio m/z. The molecules can be fragmented in the process, which can lead to different peaks in the spectrogram,

[0034] The resulting chromatograms showed clear nicotine peaks, which were quantified by the nicotine-typical m/z ratio at 133 and 162. No influences from methanol or traces of other organic compounds were found in the corresponding m/z ranges. A total of 30 suction processes were carried out and the air sucked in from puffs 1-3, 3-5, 5-10, 10-20 and 20-30 was analyzed chromatographically.

[0035] Since a measure of the amount of the substance is the integral area under the curve of a peak, the peaks were integrated for further analysis and the areas were determined in this way. For calibration, glass tubes were filled with known amounts of nicotine and these were also measured in thermal desorption. The real, actual amount of substance could be estimated from the ratios of the areas of the peaks of the calibration measurements to the areas of the actual tests.

[0036] The tests showed that around 20 g of nicotine was released after 30 puffs. It can be seen over time that the curve of the cumulative nicotine quantity is still increasing after 30 puffs. Therefore, further tests were carried out with a larger number of puffs. In addition, the course of the amount of alcohol that evaporated was quantified using the integrated alcohol sensor, although no absolute measurement was made. However, since a known amount of 100 l was used, exact quantification can be omitted. FIG. 2 shows the measured course of the cumulative nicotine quantity, and FIG. 3 shows the measured course of the cumulative alcohol quantity, whereby the alcohol quantity was only given in arbitrary units (a.u.), since, as mentioned, no exact calibration was carried out here.

[0037] In the measurements described, a pause time of 10 s between the individual puffs was programmed, so that 60 puffs were taken in 10 minutes.

[0038] As can be seen from FIG. 2, nicotine was released over 150 puffs, with the release appearing to follow a biphasic (sigmoid) curve. As can be seen from FIG. 3, alcohol was also released sigmoidally, but much faster. Nicotine release is obviously concentration-dependent. The total amount of nicotine released during this time is approximately 75% of the amount used.

[0039] As mentioned, these measurements were carried out using 3D-printed polymer tubes as evaporator tubes, which had a relatively porous wall structure. Since it can be assumed that the porous wall structure delayed evaporation due to the capillary effects and the resulting reduced exposed surface, the tests were repeated with roughened glass tubes. For this purpose, commercially available Pasteur pipettes were cut to length using a glass cutter and ground using a grinding attachment on a Dremel. This roughness led to a reduction in the contact angle below 90 and thus to a spreading of the nicotine-ethanol mixture in the glass tube. This had the effect that after just 80 puffs, i.e. about 14 minutes, all ethanol and nicotine were released, as can be seen in FIG. 4.

[0040] The results presented here fit well with previous studies by the applicants in which the residual amounts of nicotine were determined in tubes in which an alcohol-nicotine solution was vaporized. It was found that only very small residual amounts were detectable.

[0041] Finally, the influence of flavorings on the co-evaporation of nicotine with ethanol was investigated. For this purpose, the following flavorings were added to the nicotine-ethanol mixture in different test series: Smoke flavor (product no.: 01400238), Chocolate flavor (product no.: 01602888), Tea flavor (product no.: 628/19A), Coffee flavor (product no.: 01602932) and Akrastevia XI (product no.: 86600108). An amount of 10 l of each of these solutions was taken and this mixture was diluted with ethanol until only a weak (tolerable) sensory impression could be subjectively detected. 100 l of this mixture was put into an evaporator tube together with 100 l of the nicotine-ethanol solution, taking care that these solutions did not mix. Then 150 puffs were taken with the apparatus and the adsorber tubes were then eluted with methanol. As a control, the experiment was also carried out without flavorings. The methanol eluates were then applied to an Alox-RP18 thin layer chromatography plate (Alugram-RP18). After drying, a capillary force-driven run was carried out with methanol as the mobile phase. The nicotine bands visible under UV illumination did not differ visibly between the samples with flavorings and those without. This procedure was chosen because the flavorings were not precisely specified and quantified and contamination of the thermal desorption system was to be avoided.

[0042] Nicotine-ethanol evaporation measurements were repeated at least 3 times with the 3D-printed evaporator tubes and showed consistent results. The measurements with reduced evaporation time due to roughened glass surfaces and those with flavorings were each carried out twice and also showed consistent results.

[0043] These experimental studies show that by intermittent, bursty aeration of a tube in which a nicotine-ethanol solution of 1 mg/100 l is spread, significant amounts of nicotine can be transferred into the gas phase and transported away, Using a 3D-printed porous plastic tube as a carrier, around 750 g of nicotine (1 mg was applied) could be released over 30 minutes. This co-evaporation of ethanol and nicotine was also not noticeably influenced by flavorings. By choosing the appropriate surface of the evaporator tube, the speed of evaporation can be influenced to a certain extent. In the present case, with a roughened glass tube, nicotine could be released over a period of about 15 minutes with an inhalation frequency of one puff per 10 seconds, whereby here, too, about 70% of the originally applied nicotine could be detected in the gas phase.

[0044] The applicants were thus able to show that a solution according to the invention, when applying periodic air flows by suction, as corresponds to typical smoking behavior, ensures a release of the nicotine from the adhesion to the inner casing 1a into the air flow in accumulated amounts of 250-800 g within the times of 10-20 minutes corresponding to typical smoking behavior. The cigarette according to the invention thus reproduces the properties of a conventional cigarette in its nicotine release in that the nicotine is absorbed in sufficient quantities by the air flow that occurs inside the sleeve 1 during the usual suction process and is available for inhalation. The ethanol enables a co-evaporation of nicotine with ethanol, as ethanol mobilizes the otherwise difficult-to-evaporate nicotine into the gas phase. The cigarette according to the invention can also be consumed without restrictions, for example in cafes, bars or restaurants, but also in train stations or airplanes, and is compliant with non-smoking laws, as neither harmful tobacco combustion smoke nor any form of smoldering as with tobacco heaters or steam as with e-cigarettes or e-shishas is emitted.