JP7802006B2 - Aerosol-generating article with mouthpiece assembly - Google Patents

Description

The present invention relates to an aerosol-generating article having a mouthpiece assembly.

Some aerosol-generating articles heat, rather than burn, an aerosol-generating substrate, such as a tobacco-containing substrate. In such heated aerosol-generating articles, the aerosol is generated by the transfer of heat from a heat source to a physically separate aerosol-generating substrate or material, which may be located in contact with, within, around, or downstream of the heat source. During use of the aerosol-generating article, heat is transferred from the heat source to the aerosol-generating substrate, which may emit volatile compounds. These volatile compounds are entrained in air drawn through the aerosol-generating article by the user. As the emitted volatile compounds cool, they condense to form an aerosol. The aerosol may be inhaled by the user through the mouthpiece.

It would be desirable to provide an aerosol-generating article that can condense more of the emitted volatile compounds, thereby increasing the flow of aerosol through the mouthpiece. This could provide a better user experience.

An aerosol-generating article is provided for generating an inhalable aerosol upon heating. The aerosol-generating article may include a mouthpiece assembly. The mouthpiece assembly may include a first tube. The mouthpiece assembly may include a second tube. The mouthpiece assembly may include a third tube. The aerosol-generating article may include an aerosol-forming substrate. The first tube may abut against a downstream end face of the second tube. The third tube may abut against an upstream end face of the second tube. The inner diameter of the second tube may be smaller than the inner diameter of the first tube. The inner diameter of the second tube may be smaller than the inner diameter of the third tube. The inner diameter of the first tube may be at least 3 mm.

An aerosol-generating article for generating an inhalable aerosol upon heating is provided, comprising: a mouthpiece assembly including a first tube, a second tube, and a third tube; and an aerosol-forming substrate; wherein the first tube abuts against the downstream end face of the second tube; the third tube abuts against the upstream end face of the second tube; the inner diameter of the second tube is smaller than the inner diameter of the first tube; the inner diameter of the second tube is smaller than the inner diameter of the third tube; and the inner diameter of the first tube is at least 3 mm.

Also provided is an aerosol generation system comprising an aerosol generating device and an aerosol-generating article, wherein the aerosol-generating component comprises a mouthpiece assembly including a first tube, a second tube, and a third tube, and an aerosol-forming substrate, wherein the first tube abuts against the downstream end face of the second tube, the third tube abuts against the upstream end face of the second tube, the inner diameter of the second tube is smaller than the inner diameter of the first tube, the inner diameter of the second tube is smaller than the inner diameter of the third tube, and the inner diameter of the first tube is at least 3 mm.

Aerosol-generating articles with mouthpiece assemblies formed from multiple tubes, where the second tube has a narrower diameter than the first and third tubes, can increase the amount of aerosol drawn from the aerosol-generating article. This increased amount of aerosol can improve the user's experience.

Aerosol formation, particularly droplet size, depends on several factors, including temperature and air pressure.

During use of the aerosol-generating article, the volatile compounds within the aerosol-forming substrate are vaporized, for example, by thermal evaporation. The vapor cools and nucleates to form an aerosol. When a user inhales at the downstream end of the aerosol-generating article, air is drawn toward the downstream end, and the moving air entrains the aerosol and vaporized volatile compounds.

In a typical aerosol-generating article, the aerosol flows directly out the downstream end of the aerosol-generating article and is then inhaled by the user. However, in an aerosol-generating article according to the present invention, the narrow diameter second tube constricts the airflow as it passes through the mouthpiece assembly. In other words, the second tube provides a Venturi effect. As the aerosol-laden air is drawn from the second tube into the first tube, the larger diameter first tube allows the air to expand and cool, allowing more droplets to form into the aerosol. As with a typical aerosol-generating article, the aerosol is then inhaled by the user through the downstream end of the first tube.

Aerosol-generating articles therefore provide an increased volume of aerosol droplets, which may provide an improved user experience.

Furthermore, because the first tube has a larger diameter than the second tube, the resulting aerosol expansion may improve the user's filling perception.

Furthermore, forming the mouthpiece assembly from a series of tubes can provide a number of additional advantages.

First, the first, second, and third tubes may provide increased stiffness compared to, for example, a paper shell, thereby improving handling of the aerosol-generating article.

Second, it can be relatively easy to machine multiple tubes and then assemble them together, making the aerosol-generating article easier to manufacture.

Third, the use of multiple tubes provides increased flexibility in terms of inner diameter and length.

The term "aerosol-generating article" is used herein to mean an article in which an aerosol-forming substrate is heated to generate an inhalable aerosol for delivery to a consumer. As used herein, the term "aerosol-forming substrate" means a substrate capable of releasing a volatile compound upon heating to generate an aerosol.

A conventional cigarette is lit when a user applies a flame to one end of the cigarette and draws air through the other end. Localized heat provided by the flame and oxygen in the air drawn through the cigarette ignites the end of the cigarette, and the resulting combustion produces inhalable smoke. In contrast, in heated aerosol-generating articles, the aerosol is generated by heating a flavor-generating substrate (e.g., tobacco). Known heated aerosol-generating articles include, for example, electrically heated aerosol-generating articles and aerosol-generating articles in which the aerosol is generated by the transfer of heat from a combustible fuel element or heat source to a physically separated aerosol-forming material. For example, the aerosol-generating article according to the present invention finds particular application in aerosol-generating systems comprising an electrically heated aerosol generator having an internal heater blade adapted to be inserted into a rod of the aerosol-forming substrate. Aerosol-generating articles of this type have been described in the prior art, for example, in EP 081212670.

As used herein, the term "aerosol-generating device" refers to a device that includes a heater element that interacts with an aerosol-forming substrate of an aerosol-generating article to generate an aerosol.

As used herein, the term "longitudinal" refers to a direction corresponding to the major longitudinal axis of the aerosol-generating article extending between the upstream and downstream ends of the aerosol-generating article. As used herein, the terms "upstream" and "downstream" describe the relative positions of elements (or portions of elements) of the aerosol-generating article with respect to the direction in which aerosol is transported through the aerosol-generating article during use.

As used herein, the term "abut" is used to describe a component or portion of a component that directly contacts another component or portion of a component.

The mouthpiece assembly may be located toward the downstream end of the aerosol-generating article. The mouthpiece assembly may be located at the downstream end of the aerosol-generating article.

One or more of the first tube, the second tube, and the third tube may be a cellulose acetate tube. In other words, one or more of the first tube, the second tube, and the third tube may be formed from cellulose acetate. For example, the first tube may be a cellulose acetate tube. The second tube may be a cellulose acetate tube. The third tube may be a cellulose acetate tube.

Cellulose acetate tubing may alternatively be called "hollow acetate tubing" or HAT.

Advantageously, forming the first tube from cellulose acetate can further improve the rigidity and resilience of the mouthpiece assembly, thereby enhancing the user experience. Additionally, because cellulose acetate is substantially impermeable to water, forming the first tube from cellulose acetate can result in a mouthpiece assembly that is less sensitive to the humidity of the user's mouth.

The aerosol-generating article may include a fourth tube. The fourth tube may be located within an opening defined by the third tube. The fourth tube may be located within the third tube. The third tube may surround the fourth tube. The fourth tube may be aligned with the inner surface of the third tube.

The fourth tube may be formed from a substantially non-porous material. For example, the fourth tube may be formed from cardboard.

Advantageously, the fourth tube can ensure that the greatest portion of the aerosol flows along the longitudinal axis toward the second and third tubes, and not radially through the surrounding material of the third tube.

The aerosol-generating article may include a wrapper. The wrapper may be provided on the outer surface area of the mouthpiece assembly. The wrapper may be provided on the outer surface areas of the first tube, the second tube, and the third tube. The wrapper may be provided on the outer surface area of the aerosol-generating article. The wrapper may be formed from a non-porous material. In one embodiment, the wrapper is formed from cellulose acetate paper.

Advantageously, when the aerosol-generating article includes a wrapper, the radial airflow through the first, second, and third tubes may be reduced. Reducing the radial airflow through the first, second, and third tubes may increase the flow rate of the aerosol from the mouthpiece.

The ratio of the inner diameter of the first tube to the inner diameter of the second tube may be 1.2 to 5. The ratio of the inner diameter of the first tube to the inner diameter of the second tube may be 1.4 to 4. The ratio of the inner diameter of the first tube to the inner diameter of the second tube may be 1.6 to 3. The ratio of the inner diameter of the first tube to the inner diameter of the second tube may be 1.8 to 2.5.

The ratio of the inner diameter of the first tube to the inner diameter of the second tube may be 2.

In some embodiments, the ratio of the inner diameter of the first tube to the inner diameter of the second tube is a trade-off. Advantageously, maximizing this ratio may improve the expansion efficiency of the aerosol and improve the user experience. However, if this ratio is too high, the withdrawal resistance of the second tube may become too high, making the aerosol generator very difficult to use.

The ratio of the inner diameter of the first tube to the inner diameter of the third tube may be 0.5 to 2. The ratio of the inner diameter of the first tube to the inner diameter of the third tube may be 0.7 to 1.3. The ratio of the inner diameter of the first tube to the inner diameter of the third tube may be 0.8 to 1.2. The ratio of the inner diameter of the first tube to the inner diameter of the third tube may be 0.9 to 1.1. The ratio of the inner diameter of the first tube to the inner diameter of the third tube may be 0.95 to 1.05.

The ratio of the inner diameter of the first tube to the inner diameter of the third tube may be 1.

The ratio of the inner diameter of the third tube to the inner diameter of the second tube may be 1.2 to 5. The ratio of the inner diameter of the third tube to the inner diameter of the third tube may be 1.4 to 4. The ratio of the inner diameter of the third tube to the inner diameter of the third tube may be 1.6 to 3. The ratio of the inner diameter of the third tube to the inner diameter of the third tube may be 1.8 to 2.5.

The ratio of the inner diameter of the third tube to the inner diameter of the second tube may be 2.

In some embodiments, the ratio of the inner diameter of the third tube to the inner diameter of the second tube is a trade-off. Advantageously, maximizing this ratio may improve the Venturi effect of the mouthpiece assembly, which may improve nucleation. However, if this ratio is too high, the resistance to withdrawal of the second tube may be too high, making the aerosol-generating device very difficult to use. Additionally or alternatively, if this ratio is too high, the wall thickness of the third tube may be too small, thereby making the aerosol-generating article difficult to handle.

The first tube may be located downstream of the second tube. The first tube may be located downstream of the third tube. The first tube may be located at the downstream end of the mouthpiece assembly.

The longitudinal cross-sectional shape of the first tube may be circular. The longitudinal cross-sectional shape of the first tube may be annular.

The first tube may have a uniform inner diameter. In other words, the inner diameter of the first tube may be the same along its entire length.

In embodiments in which the first tube has a uniform inner diameter, the inner diameter of the first tube is considered to be the fixed diameter of the first tube.

Alternatively, the first tube may have a varying inner diameter. In other words, the inner diameter of the first tube may vary along its length. For example, the inner diameter of the first tube may increase from one end to the other. The inner diameter of the first tube may decrease from one end to the other.

In certain embodiments, the inner diameter of the first tube may increase from the upstream end of the first tube to the downstream end of the first tube. In other words, the inner diameter of the first tube at its downstream end is larger than the inner diameter of the first tube at its upstream end. Advantageously, this "funneling out" of the inner diameter of the first tube improves the taste of the aerosol.

In embodiments where the first tube has a varying inner diameter, the inner diameter of the first tube is considered to be the average diameter of the first tube.

The inner diameter of the first tube may be larger than the inner diameter of the third tube.

Advantageously, the inner diameter of the first tube is larger than the inner diameter of the third tube, which may further improve the user's filling sensation.

The first tube may have an inner diameter of at least 3 mm. The first tube may have an inner diameter of at least 3.25 mm. The first tube may have an inner diameter of at least 3.5 mm. The first tube may have an inner diameter of at least 3.75 mm. The first tube may have an inner diameter of at least 4 mm. The first tube may have an inner diameter of at least 4.25 mm. The first tube may have an inner diameter of at least 4.5 mm. The first tube may have an inner diameter of at least 4.75 mm. The first tube may have an inner diameter of at least 5 mm.

The first tube may have an inner diameter of 8 mm or less. The first tube may have an inner diameter of 7.75 mm or less. The first tube may have an inner diameter of 7.5 mm or less. The first tube may have an inner diameter of 7.25 mm or less. The first tube may have an inner diameter of 7 mm or less. The first tube may have an inner diameter of 6.75 mm or less. The first tube may have an inner diameter of 6.5 mm or less. The first tube may have an inner diameter of 6.25 mm or less. The first tube may have an inner diameter of 6 mm or less. The first tube may have an inner diameter of 5.75 mm or less. The first tube may have an inner diameter of 5.5 mm or less. The first tube may have an inner diameter of 5.25 mm or less. The first tube may have an inner diameter of 5 mm or less. The first tube may have an inner diameter of 4.75 mm or less. The first tube may have an inner diameter of 4.5 mm or less. The first tube may have an inner diameter of 4.25 mm or less. The first tube may have an inner diameter of 4 mm or less.

The first tube may have an inner diameter of 3 mm to 8 mm. The first tube may have an inner diameter of 3.25 mm to 8 mm. The first tube may have an inner diameter of 3.5 mm to 8 mm. The first tube may have an inner diameter of 3.75 mm to 8 mm. The first tube may have an inner diameter of 4 mm to 8 mm. The first tube may have an inner diameter of 4.25 mm to 5 mm. The first tube may have an inner diameter of 4.5 mm to 8 mm. The first tube may have an inner diameter of 4.75 mm to 8 mm. The first tube may have an inner diameter of 5 mm to 8 mm.

The first tube may have an inner diameter of 3 mm to 7.75 mm. The first tube may have an inner diameter of 3 mm to 7.5 mm. The first tube may have an inner diameter of 3 mm to 7.25 mm. The first tube may have an inner diameter of 3 mm to 7 mm. The first tube may have an inner diameter of 3 mm to 6.75 mm. The first tube may have an inner diameter of 3 mm to 6.5 mm. The first tube may have an inner diameter of 3 mm to 6.25 mm. The first tube may have an inner diameter of 3 mm to 6 mm. The first tube may have an inner diameter of 3 mm to 5.75 mm. The first tube may have an inner diameter of 3 mm to 5.5 mm. The first tube may have an inner diameter of 3 mm to 5.25 mm. The first tube may have an inner diameter of 3 mm to 5 mm. The first tube may have an inner diameter of 3 mm to 4.75 mm. The first tube may have an inner diameter of 3 mm to 4.5 mm. The first tube may have an inner diameter of 3 mm to 4.25 mm. The first tube may have an inner diameter of 3 mm to 4 mm.

The first tube may have an inner diameter of 3.3 mm to 6 mm. The first tube may have an inner diameter of 3.4 mm to 5.5 mm. The first tube may have an inner diameter of 3.5 mm to 5 mm. The first tube may have an inner diameter of 3.6 mm to 4.75 mm. The first tube may have an inner diameter of 3.7 mm to 4.5 mm. The first tube may have an inner diameter of 3.9 mm to 4.25 mm.

In one embodiment, the first tube has an inner diameter of 4 mm.

The first tube may have a length of at least 4 mm. The first tube may have a length of at least 4.25 mm. The first tube may have a length of at least 4.5 mm. The first tube may have a length of at least 4.75 mm. The first tube may have a length of at least 5 mm. The first tube may have a length of at least 5.25 mm. The first tube may have a length of at least 5.5 mm. The first tube may have a length of at least 5.75 mm. The first tube may have a length of at least 6 mm.

The first tube may have a length of 6 mm or less. The first tube may have a length of 5.75 mm or less. The first tube may have a length of 5.5 mm or less. The first tube may have a length of 5.25 mm or less. The first tube may have a length of 5 mm or less. The first tube may have a length of 4.75 mm or less. The first tube may have a length of 4.5 m or less. The first tube may have a length of 4.25 mm or less.

The first tube may have a length of 4 mm to 6 mm. The first tube may have a length of 4.25 mm to 6 mm. The first tube may have a length of 4.5 mm to 6 mm. The first tube may have a length of 4.75 mm to 6 mm. The first tube may have a length of 5 mm to 6 mm. The first tube may have a length of 5.25 mm to 6 mm. The first tube may have a length of 5.5 mm to 6 mm. The first tube may have a length of 5.75 mm to 6 mm.

The first tube may have a length of 4 mm to 5.75 mm. The first tube may have a length of 4 mm to 5.5 mm. The first tube may have a length of 4 mm to 5.25 mm. The first tube may have a length of 4 mm to 5 mm. The first tube may have a length of 4 mm to 4.75 mm. The first tube may have a length of 4 mm to 4.5 mm. The first tube may have a length of 4 mm to 4.25 mm.

The first tube may have a length of 4.25 mm to 5.75 mm. The first tube may have a length of 4.25 mm to 5.5 mm. The first tube may have a length of 4.5 mm to 5.75 mm. The first tube may have a length of 4.5 mm to 5.5 mm. The first tube may have a length of 4.75 mm to 5.5 mm. The first tube may have a length of 4.5 mm to 5.25 mm. The first tube may have a length of 4.75 mm to 5.25 mm. In one embodiment, the first tube has a length of 5 mm.

The second tube may be located between the first tube and the third tube. The second tube may be located in the middle of the mouthpiece assembly.

The longitudinal cross-sectional shape of the second tube may be circular. The longitudinal cross-sectional shape of the second tube may be annular.

The second tube may have a uniform inner diameter. In other words, the inner diameter of the second tube may be the same along its entire length.

In embodiments in which the second tube has a uniform inner diameter, the inner diameter of the second tube is considered to be the fixed diameter of the second tube.

Alternatively, the second tube may have a varying inner diameter. In other words, the inner diameter of the second tube may vary along its length. For example, the inner diameter of the second tube may increase from one end to the other. The inner diameter of the second tube may decrease from one end to the other.

In certain embodiments, the inner diameter of the second tube may increase from the upstream end of the second tube to the downstream end of the second tube. In other words, the inner diameter of the second tube at its downstream end is larger than the inner diameter of the third tube at its upstream end. Advantageously, this "funneling" of the inner diameter of the second tube can reduce filtration of aerosol into the second tube.

In embodiments where the second tube has a varying inner diameter, the inner diameter of the second tube is considered to be the average diameter of the second tube.

The second tube may have an inner diameter of at least 1 mm. The second tube may have an inner diameter of at least 1.25 mm. The second tube may have an inner diameter of at least 1.5 mm. The second tube may have an inner diameter of at least 1.75 mm. The second tube may have an inner diameter of at least 2 mm.

The second tube may have an inner diameter of 3 mm or less. The second tube may have an inner diameter of 2.75 mm or less. The second tube may have an inner diameter of 2.5 mm or less. The second tube may have an inner diameter of 2.25 mm or less. The second tube may have an inner diameter of 2 mm or less. The second tube may have an inner diameter of 1.75 mm or less. The second tube may have an inner diameter of 1.5 mm or less. The second tube may have an inner diameter of 1.25 mm or less.

The second tube may have an inner diameter of 1 mm to 3 mm. The second tube may have an inner diameter of 1.25 mm to 3 mm. The second tube may have an inner diameter of 1.5 mm to 3 mm. The second tube may have an inner diameter of 1.75 mm to 3 mm. The second tube may have an inner diameter of 2 mm to 3 mm. The second tube may have an inner diameter of 2.25 mm to 3 mm. The second tube may have an inner diameter of 2.5 mm to 3 mm. The second tube may have an inner diameter of 2.75 mm to 3 mm.

The second tube may have an inner diameter of 1 mm to 2.75 mm. The second tube may have an inner diameter of 1 mm to 2.5 mm. The second tube may have an inner diameter of 1 mm to 2.25 mm. The second tube may have an inner diameter of 1 mm to 2 mm. The second tube may have an inner diameter of 1 mm to 1.75 mm. The second tube may have an inner diameter of 1 mm to 1.5 mm. The second tube may have an inner diameter of 1 mm to 1.25 mm.

The second tube may have an inner diameter of 1.3 mm to 2.7 mm. The second tube may have an inner diameter of 1.4 mm to 2.6 mm. The second tube may have an inner diameter of 1.5 mm to 2.5 mm. The second tube may have an inner diameter of 1.6 mm to 2.4 mm. The second tube may have an inner diameter of 1.7 mm to 2.3 mm. The second tube may have an inner diameter of 1.8 mm to 2.2 mm.

In one embodiment, the second tube has an inner diameter of 2 mm.

The second tube may have a length of at least 4 mm. The second tube may have a length of at least 4.25 mm. The second tube may have a length of at least 4.5 mm. The second tube may have a length of at least 4.75 mm. The second tube may have a length of at least 5 mm. The second tube may have a length of at least 5.25 mm. The second tube may have a length of at least 5.5 mm. The second tube may have a length of at least 5.75 mm. The second tube may have a length of at least 6 mm.

The second tube may have a length of 6 mm or less. The second tube may have a length of 5.75 mm or less. The second tube may have a length of 5.5 mm or less. The second tube may have a length of 5.25 mm or less. The second tube may have a length of 5 mm or less. The second tube may have a length of 4.75 mm or less. The second tube may have a length of 4.5 mm or less. The second tube may have a length of 4.25 mm or less.

The second tube may have a length of 4 mm to 6 mm. The second tube may have a length of 4.25 mm to 6 mm. The second tube may have a length of 4.5 mm to 6 mm. The second tube may have a length of 4.75 mm to 6 mm. The second tube may have a length of 5 mm to 6 mm. The second tube may have a length of 5.25 mm to 6 mm. The second tube may have a length of 5.5 mm to 6 mm. The second tube may have a length of 5.75 mm to 6 mm.

The second tube may have a length of 4 mm to 5.75 mm. The second tube may have a length of 4 mm to 5.5 mm. The second tube may have a length of 4 mm to 5.25 mm. The second tube may have a length of 4 mm to 5 mm. The second tube may have a length of 4 mm to 4.75 mm. The second tube may have a length of 4 mm to 4.5 mm. The second tube may have a length of 4 mm to 4.25 mm.

The second tube may have a length of 4.25 mm to 5.75 mm. The second tube may have a length of 4.25 mm to 5.5 mm. The second tube may have a length of 4.5 mm to 5.75 mm. The second tube may have a length of 4.5 mm to 5.5 mm. The second tube may have a length of 4.75 mm to 5.5 mm. The second tube may have a length of 4.5 mm to 5.25 mm. The second tube may have a length of 4.75 mm to 5.25 mm. In one embodiment, the second tube has a length of 5 mm.

The third tube may be located upstream of the first tube. The third tube may be located upstream of the second tube. The third tube may be located at the upstream end of the mouthpiece assembly.

The longitudinal cross-sectional shape of the third tube may be circular. The longitudinal cross-sectional shape of the third tube may be annular.

The third tube may have a uniform inner diameter. In other words, the inner diameter of the third tube may be the same along its entire length.

In embodiments in which the third tube has a uniform inner diameter, the inner diameter of the third tube is considered to be the fixed diameter of the third tube.

Alternatively, the third tube may have a varying inner diameter. In other words, the inner diameter of the third tube may vary along its length. For example, the inner diameter of the third tube may decrease from one end to the other. The inner diameter of the third tube may increase from one end to the other.

In certain embodiments, the inner diameter of the third tube may decrease from the upstream end of the third tube to the downstream end of the third tube. In other words, the inner diameter of the third tube at its upstream end is larger than the inner diameter of the third tube at its downstream end. Advantageously, "funneling in" the inner diameter of the third tube improves aerosol nucleation.

In embodiments in which the third tube has a varying inner diameter, the inner diameter of the third tube is considered to be the average diameter of the third tube.

The third tube may have an inner diameter of at least 3 mm. The third tube may have an inner diameter of at least 3.25 mm. The third tube may have an inner diameter of at least 3.5 mm. The third tube may have an inner diameter of at least 3.75 mm. The third tube may have an inner diameter of at least 4 mm. The third tube may have an inner diameter of at least 4.25 mm. The third tube may have an inner diameter of at least 4.5 mm. The third tube may have an inner diameter of at least 4.75 mm. The third tube may have an inner diameter of at least 5 mm.

The third tube may have an inner diameter of 8 mm or less. The third tube may have an inner diameter of 7.75 mm or less. The third tube may have an inner diameter of 7.5 mm or less. The third tube may have an inner diameter of 7.25 mm or less. The third tube may have an inner diameter of 7 mm or less. The third tube may have an inner diameter of 6.75 mm or less. The third tube may have an inner diameter of 6.5 mm or less. The third tube may have an inner diameter of 6.25 mm or less. The third tube may have an inner diameter of 6 mm or less. The third tube may have an inner diameter of 5.75 mm or less. The third tube may have an inner diameter of 5.5 mm or less. The third tube may have an inner diameter of 5.25 mm or less. The third tube may have an inner diameter of 5 mm or less. The third tube may have an inner diameter of 4.75 mm or less. The third tube may have an inner diameter of 4.5 mm or less. The third tube may have an inner diameter of 4.25 mm or less. The third tube may have an inner diameter of 4 mm or less.

The third tube may have an inner diameter of 3 mm to 8 mm. The third tube may have an inner diameter of 3.25 mm to 8 mm. The third tube may have an inner diameter of 3.5 mm to 8 mm. The third tube may have an inner diameter of 3.75 mm to 8 mm. The third tube may have an inner diameter of 4 mm to 8 mm. The third tube may have an inner diameter of 4.25 mm to 5 mm. The third tube may have an inner diameter of 4.5 mm to 8 mm. The third tube may have an inner diameter of 4.75 mm to 8 mm. The third tube may have an inner diameter of 5 mm to 8 mm.

The third tube may have an inner diameter of 3 mm to 7.75 mm. The third tube may have an inner diameter of 3 mm to 7.5 mm. The third tube may have an inner diameter of 3 mm to 7.25 mm. The third tube may have an inner diameter of 3 mm to 7 mm. The third tube may have an inner diameter of 3 mm to 6.75 mm. The third tube may have an inner diameter of 3 mm to 6.5 mm. The third tube may have an inner diameter of 3 mm to 6.25 mm. The third tube may have an inner diameter of 3 mm to 6 mm. The third tube may have an inner diameter of 3 mm to 5.75 mm. The third tube may have an inner diameter of 3 mm to 5.5 mm. The third tube may have an inner diameter of 3 mm to 5.25 mm. The third tube may have an inner diameter of 3 mm to 5 mm. The third tube may have an inner diameter of 3 mm to 4.75 mm. The third tube may have an inner diameter of 3 mm to 4.5 mm. The third tube may have an inner diameter of 3 mm to 4.25 mm. The third tube may have an inner diameter of 3 mm to 4 mm.

The third tube may have an inner diameter of 3.3 mm to 6 mm. The third tube may have an inner diameter of 3.4 mm to 5.5 mm. The third tube may have an inner diameter of 3.5 mm to 5 mm. The third tube may have an inner diameter of 3.6 mm to 4.75 mm. The third tube may have an inner diameter of 3.7 mm to 4.5 mm. The third tube may have an inner diameter of 3.9 mm to 4.25 mm.

In one embodiment, the third tube has an inner diameter of 4 mm.

The third tube may have a length of at least 4 mm. The third tube may have a length of at least 4.25 mm. The third tube may have a length of at least 4.5 mm. The third tube may have a length of at least 4.75 mm. The third tube may have a length of at least 5 mm. The third tube may have a length of at least 5.25 mm. The third tube may have a length of at least 5.5 mm. The third tube may have a length of at least 5.75 mm. The third tube may have a length of at least 6 mm.

The third tube may have a length of 6 mm or less. The third tube may have a length of 5.75 mm or less. The third tube may have a length of 5.5 mm or less. The third tube may have a length of 5.25 mm or less. The third tube may have a length of 5 mm or less. The third tube may have a length of 4.75 mm or less. The third tube may have a length of 4.5 mm or less. The third tube may have a length of 4.25 mm or less.

The third tube may have a length of 4 mm to 6 mm. The third tube may have a length of 4.25 mm to 6 mm. The third tube may have a length of 4.5 mm to 6 mm. The third tube may have a length of 4.75 mm to 6 mm. The third tube may have a length of 5 mm to 6 mm. The third tube may have a length of 5.25 mm to 6 mm. The third tube may have a length of 5.5 mm to 6 mm. The third tube may have a length of 5.75 mm to 6 mm.

The third tube may have a length of 4 mm to 5.75 mm. The third tube may have a length of 4 mm to 5.5 mm. The third tube may have a length of 4 mm to 5.25 mm. The third tube may have a length of 4 mm to 5 mm. The third tube may have a length of 4 mm to 4.75 mm. The third tube may have a length of 4 mm to 4.5 mm. The third tube may have a length of 4 mm to 4.25 mm.

The third tube may have a length of 4.25 mm to 5.75 mm. The third tube may have a length of 4.25 mm to 5.5 mm. The third tube may have a length of 4.5 mm to 5.75 mm. The third tube may have a length of 4.5 mm to 5.5 mm. The third tube may have a length of 4.75 mm to 5.5 mm. The third tube may have a length of 4.5 mm to 5.25 mm. The third tube may have a length of 4.75 mm to 5.25 mm. In one embodiment, the third tube has a length of 5 mm.

The aerosol-generating article may have a length of at least 35 mm. The aerosol-generating article may have a length of at least 40 mm. The aerosol-generating article may have a length of at least 45 mm. The aerosol-generating article may have a length of at least 50 mm. The aerosol-generating article may have a length of at least 55 mm.

The aerosol-generating article may have a length of 60 mm or less. The aerosol-generating article may have a length of 55 mm or less. The aerosol-generating article may have a length of 50 mm or less. The aerosol-generating article may have a length of 45 mm or less. The aerosol-generating article may have a length of 40 mm or less.

The aerosol-generating article may have a length of 35 mm to 60 mm. The aerosol-generating article may have a length of 35 mm to 55 mm. The aerosol-generating article may have a length of 35 mm to 50 mm. The aerosol-generating article may have a length of 35 mm to 45 mm. The aerosol-generating article may have a length of 35 mm to 40 mm.

The aerosol-generating article may have a length of 40 mm to 60 mm. The aerosol-generating article may have a length of 45 mm to 60 mm. The aerosol-generating article may have a length of 50 mm to 60 mm. The aerosol-generating article may have a length of 55 mm to 60 mm.

The aerosol-generating article may have a length of 35 mm to 55 mm. The aerosol-generating article may have a length of 40 mm to 55 mm. The aerosol-generating article may have a length of 40 mm to 50 mm. The aerosol-generating article may have a length of 45 mm to 50 mm. The aerosol-generating article may have a length of 40 mm to 45 mm.

In one embodiment, the aerosol-generating article has a length of 45 mm.

The ratio of the inner diameter of the first tube to the outer diameter of the first tube may be 0.4 to 0.8. The ratio of the inner diameter of the first tube to the outer diameter of the first tube may be 0.5 to 0.7.

The ratio of the inner diameter of the first tube to the outer diameter of the first tube may be 0.6.

The ratio of the inner diameter of the second tube to the outer diameter of the second tube may be 0.1 to 0.5. The ratio of the inner diameter of the second tube to the outer diameter of the second tube may be 0.2 to 0.4.

The ratio of the inner diameter of the second tube to the outer diameter of the second tube may be 0.3.

The ratio of the inner diameter of the third tube to the outer diameter of the third tube may be 0.4 to 0.8. The ratio of the inner diameter of the third tube to the outer diameter of the third tube may be 0.5 to 0.7.

The ratio of the inner diameter of the third tube to the outer diameter of the third tube may be 0.6.

The first tube may have an outer diameter of at least 6 mm. The first tube may have an outer diameter of at least 6.25 mm. The first tube may have an outer diameter of at least 6.5 mm. The first tube may have an outer diameter of at least 6.75 mm. The first tube may have an outer diameter of at least 7 mm.

The first tube may have an outer diameter of 8 mm or less. The first tube may have an outer diameter of 7.75 mm or less. The first tube may have an outer diameter of 7.5 mm or less. The first tube may have an outer diameter of 7.25 mm or less. The first tube may have an outer diameter of 7 mm or less.

The first tube may have an outer diameter of 6 mm to 8 mm. The first tube may have an outer diameter of 6.25 mm to 8 mm. The first tube may have an outer diameter of 6.5 mm to 8 mm. The first tube may have an outer diameter of 6.75 mm to 8 mm. The first tube may have an outer diameter of 7 mm to 8 mm. The first tube may have an outer diameter of 7.25 mm to 8 mm. The first tube may have an outer diameter of 7.5 mm to 8 mm. The first tube may have an outer diameter of 7.75 mm to 8 mm.

The first tube may have an outer diameter of 6 mm to 7.75 mm. The first tube may have an outer diameter of 6 mm to 7.5 mm. The first tube may have an outer diameter of 6 mm to 7.25 mm. The first tube may have an outer diameter of 6 mm to 7 mm. The first tube may have an outer diameter of 6 mm to 6.75 mm. The first tube may have an outer diameter of 6 mm to 6.5 mm. The first tube may have an outer diameter of 6 mm to 6.25 mm.

The first tube may have an outer diameter of 6.25 mm to 7.75 mm. The first tube may have an outer diameter of 6.5 mm to 7.5 mm. The first tube may have an outer diameter of 6.75 mm to 7.25 mm.

The first tube may have an outer diameter of 7 mm.

The ratio of the length of the first tube to the inner diameter of the first tube may be between 0.75 and 1.75. The ratio of the length of the first tube to the inner diameter of the first tube may be between 1 and 1.5.

The ratio of the length of the first tube to the inner diameter of the first tube may be 1.25.

The ratio of the length of the second tube to the inner diameter of the second tube may be 2 to 3. The ratio of the length of the second tube to the inner diameter of the second tube may be 2.25 to 2.75.

The ratio of the length of the second tube to the inner diameter of the second tube may be 2.5.

The ratio of the length of the third tube to the inner diameter of the third tube may be between 0.75 and 1.75. The ratio of the length of the third tube to the inner diameter of the third tube may be between 1 and 1.5.

The ratio of the length of the third tube to the inner diameter of the third tube may be 1.25.

The first tube and the second tube may be arranged so that they are coaxial with one another along their longitudinal axes. The first tube and the third tube may be arranged so that they are coaxial with one another along their longitudinal axes. The second tube and the third tube may be arranged so that they are coaxial with one another along their longitudinal axes. In one embodiment, the first tube, the second tube, and the third tube may be arranged so that they are coaxial with one another along their longitudinal axes.

The aerosol-generating substrate may comprise a gel. The gel composition may comprise at least one gelling agent. The gel composition may comprise at least one alkaloid compound. The gel composition may comprise at least one cannabinoid compound. The gel composition may comprise at least one aerosol former. In one embodiment, the gel composition comprises at least one gelling agent, at least one of an alkaloid compound and a cannabinoid compound, and an aerosol former.

Advantageously, providing an aerosol-forming substrate comprising a gel composition may be desirable because it provides a uniform substrate capable of highly consistent aerosol generation. Furthermore, gel aerosol-forming substrates may have the ability to generate aerosol at lower temperatures than aerosol-forming substrates comprising tobacco. This may provide for more efficient generation of aerosol. Furthermore, this may advantageously reduce the need to cool the aerosol before it reaches the consumer.

The aerosol-forming substrate may include an annular plug of porous medium loaded with a gel composition. The porous medium may include at least one of cellulose acetate tow, crimped viscose, and crimped cotton.

The aerosol-generating article may include an upstream element. The upstream element may be located upstream of the aerosol-forming substrate. The upstream element may abut the aerosol-forming substrate. The upstream element may have a high resistance to withdrawal (RTD). The upstream element may be formed from a material that provides a high RTD. The upstream element may include a filtration material. The upstream element may include an annular plug. The upstream element may include an annular plug of fibrous filtration material.

Providing an upstream element can advantageously protect the aerosol-forming substrate and prevent the user from coming into direct contact with the aerosol-forming substrate.

Upstream elements can be used to provide greater control over the overall resistance to draw (RTD) of the aerosol-generating article. In particular, upstream elements can be advantageously used to compensate for potential reductions in RTD due to evaporation of the aerosol-forming substrate during use or due to the inclusion of other elements in the aerosol-generating article that have relatively low resistance to draw. For example, in embodiments of the present invention that include an intermediate space that contributes substantially no RTD to the overall aerosol-generating article, upstream elements can be used to add RTD to the aerosol-generating article so that an acceptable level of RTD can still be provided.

Advantageously, the upstream element can provide an overall increase in RTD without affecting the aerosol properties due to the upstream element's location upstream of the aerosol-forming substrate. While the upstream element can largely provide the desired level of RTD, this allows for the use of downstream elements that provide minimal filtration of the aerosol. Thus, the aerosol-generating article can optimize aerosol delivery from the gel composition to the consumer, while still maintaining an optimal level of RTD throughout the smoking experience.

Alternatively, or additionally, the upstream element may be advantageously adapted to compensate for a reduction in the length of other elements of the aerosol-generating article, so as to maintain a consistent overall length of the aerosol-generating article. This may advantageously allow the aerosol-forming substrate to be optimally positioned for heating when the aerosol-generating article is inserted into the aerosol generating device. This length compensation may be provided without affecting the properties of the aerosol.

Furthermore, the upstream element may advantageously provide a more uniform appearance to the upstream end of the aerosol-generating article.

In embodiments including a recess extending from the upstream end of the aerosol-generating article through the upstream element, the upstream element may include a longitudinal opening to accommodate the recess. For example, the upstream element may have an annular shape.

The aerosol-generating article may have a ventilation zone.

The ventilation zone may include one or more rows of ventilation perforations. The one or more rows of ventilation perforations may be formed through the wall of at least one of the first tube, the second tube, and the third tube. In one example, the one or more rows of ventilation perforations are formed through the wall of the third tube. In embodiments including a wrapper, the one or more rows of ventilation perforations are formed through the wrapper. Advantageously, the one or more rows of ventilation perforations provide a ventilation effect that can enhance cooling of vaporized volatile compounds on the aerosol-forming substrate, thereby improving aerosol nucleation.

The ventilation zone may include only one row of ventilation perforations. Advantageously, by concentrating the cooling effect provided by the ventilation on a short portion of the aerosol-generating article, it may be possible to further enhance aerosol nucleation. This is because the faster and more dramatic cooling of the volatilized compound stream is expected to be particularly favorable for the formation of new aerosol particle nuclei.

One or more rows of ventilation perforations may be circumferentially disposed around the wall of at least one of the first tube, the second tube, and the third tube. When the ventilation zone includes two or more rows of ventilation perforations, the rows of ventilation perforations may be longitudinally spaced apart from one another along at least one of the first tube, the second tube, and the third tube. By way of example, adjacent rows of ventilation perforations may be longitudinally spaced apart from one another by a distance of approximately 0.25 millimeters to 0.75 millimeters.

At least one of the ventilation perforations may have an equivalent diameter of at least 100 μm. At least one of the ventilation perforations may have an equivalent diameter of at least 150 μm. At least one of the ventilation perforations may have an equivalent diameter of at least 200 μm.

At least one of the vent perforations may have an equivalent diameter of less than 500 μm. At least one of the vent perforations may have an equivalent diameter of less than 450 μm. The term "equivalent diameter" is used herein to mean the diameter of a circle having the same surface area as the cross-section of the vent perforation. The cross-section of the vent perforation may have any suitable shape. In one embodiment, the vent perforation has a circular cross-sectional shape.

The ventilation perforations may be of uniform size. Alternatively, the ventilation perforations may vary in size. By varying the number and size of the ventilation perforations, it is possible to adjust the amount of ambient air that enters the first tube, the second tube, and/or the third tube when a consumer draws on the aerosol-generating article during use. Thus, it is advantageously possible to adjust the level of ventilation in the aerosol-generating article.

The vent perforations can be formed using any suitable technique, such as by laser techniques, mechanical perforation of the first tube, second tube, and/or third tube as part of the aerosol-generating article, or pre-perforation of the first tube, second tube, and/or third tube before they are combined with other elements to form the aerosol-generating article. Preferably, the vent perforations are formed by online laser perforation.

The distance between the ventilation zone and the upstream end of the aerosol-generating article may be less than 50 mm. The distance between the ventilation zone and the upstream end of the aerosol-generating article may be less than 45 mm. The distance between the ventilation zone and the upstream end of the aerosol-generating article may be less than 40 mm.

The distance between the ventilation zone and the upstream end of the aerosol-generating article is preferably at least 12 mm. The distance between the ventilation zone and the upstream end of the aerosol-generating article may be at least 15 mm. The distance between the ventilation zone and the upstream end of the aerosol-generating article may be at least 20 mm. The distance between the ventilation zone and the upstream end of the aerosol-generating article may preferably be at least 25 mm.

The distance between the ventilation zone and the downstream end of the aerosol-forming substrate may be at least 2 mm. The distance between the ventilation zone and the downstream end of the aerosol-forming substrate may be at least 4 mm. The distance between the ventilation zone and the downstream end of the aerosol-forming substrate may be at least 5 mm. The distance between the ventilation zone and the downstream end of the aerosol-forming substrate may be at least 10 mm. The distance between the ventilation zone and the downstream end of the aerosol-forming substrate may be at least about 15 mm.

The distance between the ventilation zone and the downstream end of the aerosol-forming substrate may be less than 35 mm. The distance between the ventilation zone and the downstream end of the aerosol-forming substrate may be less than 30 mm. The distance between the ventilation zone and the downstream end of the aerosol-forming substrate may be less than 25 mm.

In practice, the ventilation zone may divide the cavity defined within the aerosol-generating article into an upstream sub-cavity extending longitudinally from the upstream end of the aerosol-generating article to the location of the ventilation zone, and a downstream sub-cavity extending longitudinally from the location of the ventilation zone to the downstream end of the aerosol-generating article. Without wishing to be bound by theory, it is understood that in the upstream sub-cavity, the volatilized compounds of the aerosol stream slowly travel downstream along the cavity and cool, for example, by losing some of their heat to the surrounding walls of the third tube. Thus, aerosol particles begin to nucleate. Meanwhile, in the downstream sub-cavity, the aerosol stream and ventilation air rapidly mix, which rapidly cools the volatilized compounds of the aerosol stream and thus favors the nucleation of new aerosol particles and the growth of existing aerosol particles as the aerosol travels downstream.

The aerosol-generating article may include a recess extending from the upstream end of the aerosol-generating article. The recess may extend through the upstream element. The recess may extend through at least a portion of the aerosol-forming substrate.

Providing a recessed portion may advantageously allow the aerosol-generating article to be heated using an internal heater, such as a pin or blade heater. This may facilitate more efficient heating of the aerosol-forming substrate. The inclusion of a recessed portion is particularly advantageous because gel-containing aerosol-forming substrates typically have a higher density than tobacco-containing aerosol-forming substrates. As a result, it is impractical to insert a pin or blade heater directly into a gel-containing aerosol-forming substrate compared to a tobacco-containing aerosol-forming substrate. Furthermore, providing a recessed portion may prevent the heater from coming into contact with the gel aerosol-forming substrate, which may help keep the heater clean.

The recess may be defined by a longitudinal opening extending through the upstream element and a longitudinal opening extending through at least a portion of the aerosol-forming substrate. The longitudinal opening extending through the upstream element and the longitudinal opening extending through at least a portion of the aerosol-forming substrate may have substantially the same diameter and may be substantially aligned.

The recess may have any cross-sectional shape. The recess may have a constant cross-sectional shape. The shape of the recess may be configured to correspond to the shape of the heater of the aerosol generating device used with the aerosol-generating article. The recess may have a circular cross-sectional shape. A recess having a circular cross-sectional shape may be appropriate when the heater is a pin heater. The recess may have an elliptical or rectangular shape. A recess having an elliptical or rectangular cross-sectional shape may be appropriate when the heater is a blade heater. Preferably, the recess has a circular cross-sectional shape.

The recessed portion may be centrally disposed along the longitudinal axis of the aerosol-generating article. This may advantageously simplify insertion of the aerosol-generating article into the aerosol-generating device, as the orientation of the aerosol-generating device is not critical. Furthermore, centrally locating the recessed portion may advantageously ensure even heating of the aerosol-forming substrate.

The recessed portion may have any diameter. Preferably, the recessed portion has a diameter that is the same as or slightly larger than the diameter of the heater of the aerosol generating device used with the aerosol-generating article.

The diameter of the recess may be from about 0.5 mm to about 10 mm. The diameter of the recess may be from about 1 mm to about 8 mm, or from about 2 mm to about 6 mm.

The recessed portion may have any length. Preferably, the recessed portion has a length that is the same as or slightly greater than the length of the heater of the aerosol generating device used with the aerosol-generating article.

The length of the recess may be from about 5 millimeters to about 30 millimeters. For example, the length of the recess may be from about 10 millimeters to about 25 millimeters, or from about 15 millimeters to about 20 millimeters.

The recess may extend through the entire length of the aerosol-forming substrate. In this case, the recess may extend further downstream from the downstream end of the aerosol-forming substrate. Alternatively, in this case, the recess may extend to the downstream end of the aerosol-forming substrate but not further downstream.

Preferably, the gel composition comprises an alkaloid compound, or a cannabinoid compound, or both an alkaloid compound and a cannabinoid compound, an aerosol former, and at least one gelling agent. Preferably, the at least one gelling agent forms a solid medium, the glycerol is dispersed in the solid medium, and the alkaloid or cannabinoid is dispersed in the glycerol. Preferably, the gel composition is in a stable gel phase.

Advantageously, the stable gel composition containing nicotine provides a predictable composition shape upon storage or upon transition from manufacture to consumer. The stable gel composition containing nicotine substantially maintains its shape. The stable gel composition containing nicotine does not substantially release a liquid phase upon storage or upon transition from manufacture to consumer. The stable gel composition containing nicotine may provide a simple consumable design. The consumable may not need to be designed to contain a liquid, and therefore a wider range of materials and container configurations may be contemplated.

The gel compositions described herein may be combined with an aerosol generating device to provide nicotine aerosol to the lungs at inhalation or airflow rates within those of traditional smoking. The aerosol generating device may continuously heat the gel composition. The consumer may take multiple inhalations or "puffs," with each "puff" delivering a quantity of nicotine aerosol. When heated, the gel composition may deliver a high nicotine/total particulate matter (TPM) aerosol to the consumer, preferably in a continuous manner.

The phrase "stable gel phase" or "stable gel" refers to a gel that substantially maintains its shape and mass when exposed to various environmental conditions. A stable gel cannot substantially release or absorb water (sweat) when exposed to standard temperatures and pressures while varying relative humidity from about 10 percent to about 60 percent. For example, a stable gel can substantially maintain its shape and mass when exposed to standard temperatures and pressures while varying relative humidity from about 10 percent to about 60 percent.

The gel composition may contain an alkaloid compound, or a cannabinoid compound, or both an alkaloid compound and a cannabinoid compound. The gel composition may contain one or more alkaloids. The gel composition may contain one or more cannabinoids. The gel composition may contain a combination of one or more alkaloids and one or more cannabinoids.

The term "alkaloid compound" refers to any of a class of naturally occurring organic compounds containing one or more basic nitrogen atoms. Generally, alkaloids contain at least one nitrogen atom in an amine-type structure. This or another nitrogen atom within the molecule of an alkaloid compound can be active as a base in an acid-base reaction. Most alkaloid compounds have one or more of their nitrogen atoms as part of a ring system, e.g., a heterocycle. In nature, alkaloid compounds are found primarily in plants and are particularly common in certain families of flowering plants. However, some alkaloid compounds are found in animal species and fungi. In this disclosure, the term "alkaloid compound" refers to both naturally occurring and synthetically produced alkaloid compounds.

The gel composition preferably contains an alkaloid compound selected from the group consisting of nicotine, anatabine, and combinations thereof.

Preferably, the gel composition contains nicotine.

The term "nicotine" refers to nicotine and nicotine derivatives (e.g., free base nicotine, nicotine salts, and the like).

The term "cannabinoid compounds" refers to any one of a class of naturally occurring compounds found in parts of the cannabis plant, including Cannabis sativa, Cannabis indica, and Cannabis ruderalis. Cannabinoid compounds are particularly concentrated in the female flower heads. Cannabinoid compounds that occur naturally in the cannabis plant include cannabidiol (CBD) and tetrahydrocannabinol (THC). In this disclosure, the term "cannabinoid compounds" is used to describe both naturally occurring and synthetically produced cannabinoid compounds.

The gel may contain a cannabinoid compound selected from the group consisting of cannabidiol (CBD), tetrahydrocannabinol (THC), tetrahydrocannabinolic acid (THCA), cannabidiolic acid (CBDA), cannabinol (CBN), cannabigerol (CBG), cannabichromene (CBC), cannabicyclol (CBL), cannabivarin (CBV), tetrahydrocannabivarin (THCV), cannabidivarin (CBDV), cannabichromevarin (CBCV), cannabigerovarin (CBGV), cannabigerol monomethyl ether (CBGM), cannabielsoin (CBE), cannabicitran (CBT), and combinations thereof.

The gel composition may preferably contain a cannabinoid compound selected from the group consisting of cannabidiol (CBD), THC (tetrahydrocannabinol), and combinations thereof.

The gel preferably contains cannabidiol (CBD).

The gel composition may contain nicotine and cannabidiol (CBD).

The gel composition may contain nicotine, cannabidiol (CBD), and THC (tetrahydrocannabinol).

The gel composition preferably contains about 0.5 weight percent to about 10 weight percent alkaloid compounds, or about 0.5 weight percent to about 10 weight percent cannabinoid compounds, or a total amount of about 0.5 weight percent to about 10 weight percent of both alkaloid compounds and cannabinoid compounds. The gel composition may contain about 0.5 weight percent to about 5 weight percent alkaloid compounds, or about 0.5 weight percent to about 5 weight percent cannabinoid compounds, or a total amount of about 0.5 weight percent to about 5 weight percent of both alkaloid compounds and cannabinoid compounds. The gel composition preferably contains about 1 weight percent to about 3 weight percent alkaloid compounds, or about 1 weight percent to about 3 weight percent cannabinoid compounds, or a total amount of about 1 weight percent to about 3 weight percent of both alkaloid compounds and cannabinoid compounds. The gel composition may preferably contain about 1.5 weight percent to about 2.5 weight percent alkaloid compounds, or about 1.5 weight percent to about 2.5 weight percent cannabinoid compounds, or a total amount of about 1.5 weight percent to about 2.5 weight percent alkaloid compounds and cannabinoid compounds. The gel composition may preferably contain about 2 weight percent alkaloid compounds, or about 2 weight percent cannabinoid compounds, or a total amount of about 2 weight percent alkaloid compounds and cannabinoid compounds. The alkaloid compound component of the gel formulation may be the most volatile component of the gel formulation. In some embodiments, water may be the most volatile component of the gel formulation, and the alkaloid compound component of the gel formulation may be the second most volatile component of the gel formulation. The cannabinoid compound component of the gel formulation may be the most volatile component of the gel formulation. In some embodiments, water may be the most volatile component of the gel formulation, and the alkaloid compound component of the gel formulation may be the second most volatile component of the gel formulation.

Preferably, nicotine is included in the gel composition. Nicotine may be added to the composition in free base or salt form. The gel composition comprises about 0.5 weight percent to about 10 weight percent nicotine, or about 0.5 weight percent to about 5 weight percent nicotine. Preferably, the gel composition comprises about 1 weight percent to about 3 weight percent nicotine, or about 1.5 weight percent to about 2.5 weight percent nicotine, or about 2 weight percent nicotine. The nicotine component of the gel formulation may be the most volatile component of the gel formulation. In some embodiments, water may be the most volatile component of the gel formulation, and the nicotine component of the gel formulation may be the second most volatile component of the gel formulation.

The gel composition further includes an aerosol former. Ideally, the aerosol former is substantially resistant to thermal degradation at the operating temperature of the associated aerosol-generating device. Suitable aerosol formers include, but are not limited to, polyhydric alcohols (e.g., triethylene glycol, 1,3-butanediol, glycerin), esters of polyhydric alcohols (e.g., glycerol monoacetate, diacetate, or triacetate), and aliphatic esters of monocarboxylic, dicarboxylic, or polycarboxylic acids (e.g., dimethyl dodecanedioate, dimethyl tetradecanedioate). The polyhydric alcohol or mixture thereof can be one or more of triethylene glycol, 1,3-butanediol, and glycerin (glycerol or propane-1,2,3-triol) or polyethylene glycol. The aerosol former is preferably glycerol.

The gel composition comprises a majority of the aerosol former. The gel composition may comprise a mixture of water and aerosol former, with the aerosol former forming a majority (by weight) of the gel composition. The aerosol former may form at least about 50 weight percent of the gel composition. The aerosol former may form at least about 60 weight percent, or at least about 65 weight percent, or at least about 70 weight percent of the gel composition. The aerosol former may form about 70 weight percent to about 80 weight percent of the gel composition. The aerosol former may form about 70 weight percent to about 75 weight percent of the gel composition.

The gel composition may comprise a majority of glycerol. The gel composition may comprise a mixture of water and glycerol, with glycerol forming a majority (by weight) of the gel composition. Glycerol may form at least about 50 weight percent of the gel composition. Glycerol may form at least about 60 weight percent, or at least about 65 weight percent, or at least about 70 weight percent of the gel composition. Glycerol may form about 70 weight percent to about 80 weight percent of the gel composition. Glycerol may form about 70 weight percent to about 75 weight percent of the gel composition.

The gel composition further comprises at least one gelling agent. Preferably, the gel composition comprises a total amount of gelling agents in the range of about 0.4 weight percent to about 10 weight percent. More preferably, the composition comprises gelling agents in the range of about 0.5 weight percent to about 8 weight percent. More preferably, the composition comprises gelling agents in the range of about 1 weight percent to about 6 weight percent. More preferably, the composition comprises gelling agents in the range of about 2 weight percent to about 4 weight percent. More preferably, the composition comprises gelling agents in the range of about 2 weight percent to about 3 weight percent.

The term "gelling agent" refers to a compound that, when homogeneously added in an amount of about 0.3 weight percent to a 50 weight percent water/50 weight percent glycerol mixture, leads to the formation of a solid medium or support matrix, leading to a gel. Gelling agents include, but are not limited to, hydrogen-bond cross-linking gelling agents and ionic cross-linking gelling agents.

The gelling agent may include one or more biopolymers. The biopolymers may be formed from polysaccharides.

Biopolymers include, for example, gellan gum (natural gellan gum, low acyl gellan gum, high acyl gellan gum, and low acyl gellan gum are preferred), xanthan gum, alginate (alginic acid), agar, and guar gum. It may be preferable for the composition to include xanthan gum. The composition may include two biopolymers. The composition may include three biopolymers. The composition may include two biopolymers in substantially equal amounts by weight. The composition may include three biopolymers in substantially equal amounts by weight.

Preferably, the gel composition contains at least about 0.2 weight percent of a hydrogen-bond cross-linked gelling agent. Alternatively or additionally, the gel composition preferably contains at least about 0.2 weight percent of an ionic cross-linked gelling agent. Most preferably, the gel composition contains at least about 0.2 weight percent of a hydrogen-bond cross-linked gelling agent and at least about 0.2 weight percent of an ionic cross-linked gelling agent. The gel composition may contain about 0.5 weight percent to about 3 weight percent of a hydrogen-bond cross-linked gelling agent and about 0.5 weight percent to about 3 weight percent of an ionic cross-linked gelling agent, or about 1 weight percent to about 2 weight percent of a hydrogen-bond cross-linked gelling agent and about 1 weight percent to about 2 weight percent of an ionic cross-linked gelling agent. The hydrogen-bond cross-linked gelling agent and the ionic cross-linked gelling agent may be present in substantially equal amounts in the gel composition.

The term "hydrogen-bond cross-linking gelator" refers to a gelator that forms non-covalent or physical cross-links via hydrogen bonds. Hydrogen bonds are not covalent bonds to hydrogen atoms, but rather a type of intermolecular electrostatic dipole-dipole attraction. They result from the attraction between a hydrogen atom covalently bonded to an extremely electronegative atom, such as an N, O, or F atom, and another extremely electronegative atom.

The hydrogen-bond cross-linking gelling agent may include one or more of galactomannan, gelatin, agarose, konjac gum, or agar. It may be preferable for the hydrogen-bond cross-linking gelling agent to include agar.

The gel composition preferably contains a hydrogen-bond cross-linking gelling agent in the range of about 0.3 weight percent to about 5 weight percent. Preferably, the composition contains a hydrogen-bond cross-linking gelling agent in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the composition contains a hydrogen-bond cross-linking gelling agent in the range of about 1 weight percent to about 2 weight percent.

The gel composition may contain galactomannan in the range of about 0.2 weight percent to about 5 weight percent. Preferably, the galactomannan may be in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the galactomannan may be in the range of about 0.5 weight percent to about 2 weight percent. Preferably, the galactomannan may be in the range of about 1 weight percent to about 2 weight percent.

The gel composition may contain gelatin in the range of about 0.2 weight percent to about 5 weight percent. Preferably, the gelatin may be in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the gelatin may be in the range of about 0.5 weight percent to about 2 weight percent. Preferably, the gelatin may be in the range of about 1 weight percent to about 2 weight percent.

The gel composition may contain agarose in the range of about 0.2 weight percent to about 5 weight percent. Preferably, the agarose may be in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the agarose may be in the range of about 0.5 weight percent to about 2 weight percent. Preferably, the agarose may be in the range of about 1 weight percent to about 2 weight percent.

The gel composition may contain konjac gum in the range of about 0.2 weight percent to about 5 weight percent. Preferably, the konjac gum may be in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the konjac gum may be in the range of about 0.5 weight percent to about 2 weight percent. Preferably, the konjac gum may be in the range of about 1 weight percent to about 2 weight percent.

The gel composition may contain agar in the range of about 0.2 weight percent to about 5 weight percent. Preferably, the agar may be in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the agar may be in the range of about 0.5 weight percent to about 2 weight percent. Preferably, the agar may be in the range of about 1 weight percent to about 2 weight percent.

The term "ionically cross-linking gelator" refers to a gelator that forms non-covalent or physical cross-links through ionic bonds. Ionic cross-linking involves the association of polymer chains through non-covalent interactions. A cross-linked network is formed when multivalent molecules with opposite charges are electrostatically attracted to each other, resulting in a cross-linked polymer network.

The ionic cross-linking gelling agent may include low acyl gellan, pectin, kappa carrageenan, iota carrageenan, or alginate. The ionic cross-linking gelling agent may preferably include low acyl gellan.

The gel composition may contain an ionically cross-linked gelling agent in the range of about 0.3 weight percent to about 5 weight percent. Preferably, the composition contains an ionically cross-linked gelling agent in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the composition contains an ionically cross-linked gelling agent in the range of about 1 weight percent to about 2 weight percent.

The gel composition may contain low-acyl gellan in the range of about 0.2 weight percent to about 5 weight percent. Preferably, the low-acyl gellan may be in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the low-acyl gellan may be in the range of about 0.5 weight percent to about 2 weight percent. Preferably, the low-acyl gellan may be in the range of about 1 weight percent to about 2 weight percent.

The gel composition may contain pectin in the range of about 0.2 weight percent to about 5 weight percent. Preferably, the pectin may be in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the pectin may be in the range of about 0.5 weight percent to about 2 weight percent. Preferably, the pectin may be in the range of about 1 weight percent to about 2 weight percent.

The gel composition may contain kappa carrageenan in the range of about 0.2 weight percent to about 5 weight percent. Preferably, the kappa carrageenan may be in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the kappa carrageenan may be in the range of about 0.5 weight percent to about 2 weight percent. Preferably, the kappa carrageenan may be in the range of about 1 weight percent to about 2 weight percent.

The gel composition may contain iota carrageenan in the range of about 0.2 weight percent to about 5 weight percent. Preferably, the iota carrageenan may be in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the iota carrageenan may be in the range of about 0.5 weight percent to about 2 weight percent. Preferably, the iota carrageenan may be in the range of about 1 weight percent to about 2 weight percent.

The gel composition may contain alginate in the range of about 0.2 weight percent to about 5 weight percent. Preferably, the alginate may be in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the alginate may be in the range of about 0.5 weight percent to about 2 weight percent. Preferably, the alginate may be in the range of about 1 weight percent to about 2 weight percent.

The gel composition may contain a hydrogen-bond cross-linking gelator and an ionic cross-linking gelator in a ratio of about 3:1 to about 1:3. Preferably, the gel composition may contain a hydrogen-bond cross-linking gelator and an ionic cross-linking gelator in a ratio of about 2:1 to about 1:2. Preferably, the gel composition may contain a hydrogen-bond cross-linking gelator and an ionic cross-linking gelator in a ratio of about 1:1.

The gel composition may further comprise a thickening agent. Thickening agents in combination with hydrogen-bond cross-linking gelling agents and ionic cross-linking gelling agents surprisingly appear to support a solid medium and maintain the gel composition even when the gel composition contains high levels of glycerol.

The term "thickener" refers to a compound that, when uniformly added in an amount of 0.3 weight percent to a 50 weight percent water/50 weight percent glycerin mixture at 25°C, increases the viscosity without resulting in the formation of a gel, and causes the mixture to remain fluid. Preferably, a thickener refers to a compound that, when uniformly added in an amount of 0.3 weight percent to a 50 weight percent water/50 weight percent glycerin mixture at 25°C, increases the viscosity to at least 50 cPs, preferably at least 200 cPs, preferably at least 500 cPs, and preferably at least 1000 cPs, at a shear rate of 0.1 s-1, without resulting in the formation of a gel, and causes the mixture to remain fluid. Preferably, a thickener refers to a compound that, when homogeneously added in an amount of 0.3 weight percent to a mixture of 50 weight percent water and 50 weight percent glycerol at 25°C, increases the viscosity at a shear rate of 0.1 s-1 by at least 2 times, at least 5 times, at least 10 times, or at least 100 times greater than before addition without causing gel formation, allowing the mixture to remain fluid or preserved.

Viscosity values provided herein may be measured using a Brookfield RVT viscometer with a disk-type RV#2 spindle rotating at 25°C and a speed of 6 revolutions per minute (rpm).

The gel composition preferably contains a thickener in the range of about 0.2 weight percent to about 5 weight percent. Preferably, the composition contains a thickener in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the composition contains a thickener in the range of about 0.5 weight percent to about 2 weight percent. Preferably, the composition contains a thickener in the range of about 1 weight percent to about 2 weight percent.

The thickener may include one or more of xanthan gum, carboxymethylcellulose, microcrystalline cellulose, methylcellulose, gum arabic, guar gum, lambda carrageenan, or starch. Preferably, the thickener may include xanthan gum.

The gel composition may contain xanthan gum in the range of about 0.2 weight percent to about 5 weight percent. Preferably, the xanthan gum may be in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the xanthan gum may be in the range of about 0.5 weight percent to about 2 weight percent. Preferably, the xanthan gum may be in the range of about 1 weight percent to about 2 weight percent.

The gel composition may contain carboxymethylcellulose in the range of about 0.2 weight percent to about 5 weight percent. Preferably, the carboxymethylcellulose may be in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the carboxymethylcellulose may be in the range of about 0.5 weight percent to about 2 weight percent. Preferably, the carboxymethylcellulose may be in the range of about 1 weight percent to about 2 weight percent.

The gel composition may contain microcrystalline cellulose in the range of about 0.2 weight percent to about 5 weight percent. Preferably, the microcrystalline cellulose may be in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the microcrystalline cellulose may be in the range of about 0.5 weight percent to about 2 weight percent. Preferably, the microcrystalline cellulose may be in the range of about 1 weight percent to about 2 weight percent.

The gel composition may contain methylcellulose in the range of about 0.2 weight percent to about 5 weight percent. Preferably, the methylcellulose may be in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the methylcellulose may be in the range of about 0.5 weight percent to about 2 weight percent. Preferably, the methylcellulose may be in the range of about 1 weight percent to about 2 weight percent.

The gel composition may include gum arabic in the range of about 0.2 weight percent to about 5 weight percent. Preferably, gum arabic may be in the range of about 0.5 weight percent to about 3 weight percent. Preferably, gum arabic may be in the range of about 0.5 weight percent to about 2 weight percent. Preferably, gum arabic may be in the range of about 1 weight percent to about 2 weight percent.

The gel composition may contain guar gum in the range of about 0.2 weight percent to about 5 weight percent. Preferably, the guar gum may be in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the guar gum may be in the range of about 0.5 weight percent to about 2 weight percent. Preferably, the guar gum may be in the range of about 1 weight percent to about 2 weight percent.

The gel composition may contain lambda carrageenan in the range of about 0.2 weight percent to about 5 weight percent. Preferably, the lambda carrageenan may be in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the lambda carrageenan may be in the range of about 0.5 weight percent to about 2 weight percent. Preferably, the lambda carrageenan may be in the range of about 1 weight percent to about 2 weight percent.

The gel composition may contain starch in the range of about 0.2 weight percent to about 5 weight percent. Preferably, the starch may be in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the starch may be in the range of about 0.5 weight percent to about 2 weight percent. Preferably, the starch may be in the range of about 1 weight percent to about 2 weight percent.

The gel composition may further include a divalent cation. Preferably, the divalent cation includes calcium ions, such as calcium lactate in solution. The divalent cation (e.g., calcium ions) may assist in gel formation in compositions that include a gelling agent, such as an ionically crosslinked gelling agent. The ionic effect may assist in gel formation. The divalent cation may be present in the gel composition in a range of about 0.1 to about 1 weight percent, or about 0.5 to about 1 weight percent.

The gel composition may further include an acid. The acid may include a carboxylic acid. The carboxylic acid may include a ketone group. Preferably, the carboxylic acid may include a ketone group having fewer than about 10 carbon atoms, such as levulinic acid or lactic acid, or fewer than about 6 carbon atoms, or fewer than about 4 carbonate atoms. Preferably, the carboxylic acid has three carbon atoms (such as lactic acid). Lactic acid surprisingly improves the stability of the gel composition over similar carboxylic acids. The carboxylic acid may aid in gel formation. The carboxylic acid may reduce changes in the alkaloid compound concentration, or cannabinoid compound concentration, or both the alkaloid compound concentration and the cannabinoid compound concentration in the gel composition during storage. The carboxylic acid may reduce changes in the nicotine concentration in the gel composition during storage.

The gel composition may contain carboxylic acid in the range of about 0.1 weight percent to about 5 weight percent. Preferably, the carboxylic acid may be in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the carboxylic acid may be in the range of about 0.5 weight percent to about 2 weight percent. Preferably, the carboxylic acid may be in the range of about 1 weight percent to about 2 weight percent.

The gel composition may contain lactic acid in the range of about 0.1 weight percent to about 5 weight percent. Preferably, the lactic acid may be in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the lactic acid may be in the range of about 0.5 weight percent to about 2 weight percent. Preferably, the lactic acid may be in the range of about 1 weight percent to about 2 weight percent.

The gel composition may contain levulinic acid in the range of about 0.1 weight percent to about 5 weight percent. Preferably, the levulinic acid may be in the range of about 0.5 weight percent to about 3 weight percent. Preferably, the levulinic acid may be in the range of about 0.5 weight percent to about 2 weight percent. Preferably, the levulinic acid may be in the range of about 1 weight percent to about 2 weight percent.

The gel composition preferably contains some water. The gel composition is more stable when the composition contains some water. Preferably, the gel composition contains at least about 1 weight percent, or at least about 2 weight percent, or at least about 5 weight percent water. Preferably, the gel composition contains at least about 10 weight percent or at least about 15 weight percent water.

The gel composition preferably contains about 8 weight percent to about 32 weight percent water. The gel composition preferably contains about 15 weight percent to about 25 weight percent water. The gel composition preferably contains about 18 weight percent to about 22 weight percent water. The gel composition preferably contains about 20 weight percent water.

Preferably, the aerosol-forming substrate contains from about 150 mg to about 350 mg of the gel composition.

The present invention is defined in the claims. However, the following provides a non-exhaustive list of non-limiting examples. Any one or more of the features of these examples may be combined with any one or more features of any other example, embodiment, or aspect described herein.

Example 1:
An aerosol-generating article for generating an inhalable aerosol upon heating, the aerosol-generating article comprising: a mouthpiece assembly including a first tube, a second tube, and a third tube; and an aerosol-forming substrate; wherein the first tube abuts against a downstream end face of the second tube, the third tube abuts against an upstream end face of the second tube, the second tube having an inner diameter smaller than that of the first tube, the second tube having an inner diameter smaller than that of the third tube, and the first tube having an inner diameter of at least 3 mm.
Example 2:
10. The aerosol-generating article of claim 1, wherein the inner diameter of the first tube is larger than the inner diameter of the third tube.
Example 3:
The aerosol-generating article of Example 1 or Example 2, wherein the first tube is a cellulose acetate tube.
Example 4:
The aerosol-generating article of any preceding embodiment, wherein the second tube is a cellulose acetate tube.
Example 5:
The aerosol-generating article of any preceding embodiment, wherein the third tube is a cellulose acetate tube.
Example 6:
An aerosol-generating article according to any preceding example, comprising a fourth tube located within the opening defined by the third tube.
Example 7:
7. The aerosol-generating article of example 6, wherein the fourth tube is formed from a material that is substantially impermeable to air.
Example 8:
The aerosol-generating article of Example 7, wherein the fourth tube is formed from cardboard.
Example 9:
An aerosol-generating article according to any preceding embodiment, comprising a wrapper provided on an outer surface area of the first tube, the second tube, and the third tube.
Example 10:
10. The aerosol-generating article of example 9, wherein the wrapper is formed from a non-porous material.
Example 11:
The aerosol-generating article of any preceding embodiment, wherein the ratio of the inner diameter of the first tube to the inner diameter of the second tube is 1.2 to 5.
Example 12:
12. The aerosol-generating article of claim 11, wherein the ratio of the inner diameter of the first tube to the inner diameter of the second tube is 1.8 to 2.5.
Example 13:
The aerosol-generating article of any preceding embodiment, wherein the ratio of the inner diameter of the first tube to the inner diameter of the third tube is 0.5 to 2.
Example 14:
14. The aerosol-generating article of claim 13, wherein the ratio of the inner diameter of the first tube to the inner diameter of the third tube is 0.8 to 1.2.
Example 15:
The aerosol-generating article of any preceding embodiment, wherein the ratio of the inner diameter of the third tube to the inner diameter of the second tube is 1.5 to 5.
Example 16:
16. The aerosol-generating article of Example 15, wherein the ratio of the inner diameter of the third tube to the inner diameter of the second tube is 1.8 to 2.5.
Example 17:
The aerosol-generating article of any preceding example, wherein the first tube has an inner diameter of between 3 mm and 8 mm.
Example 18:
The aerosol-generating article of Example 17, wherein the first tube has an inner diameter of 4 mm.
Example 19:
The aerosol-generating article of any preceding example, wherein the first tube has a length of between 4 mm and 6 mm.
Example 20:
20. The aerosol-generating article of Example 19, wherein the first tube has a length of 5 mm.
Example 21:
The aerosol-generating article of any preceding Example, wherein the second tube has an inner diameter of between 1 mm and 3 mm.
Example 22:
22. The aerosol-generating article of Example 21, wherein the second tube has an inner diameter of 2 mm.
Example 23:
The aerosol-generating article of any preceding Example, wherein the second tube has a length of between 4 mm and 6 mm.
Example 24:
24. The aerosol-generating article of example 23, wherein the second tube has a length of 5 millimeters.
Example 25:
The aerosol-generating article of any preceding example, wherein the third tube has an inner diameter of between 3 mm and 8 mm.
Example 26:
The aerosol-generating article of Example 25, wherein the third tube has an inner diameter of 4 mm.
Example 27:
The aerosol-generating article of any preceding embodiment, wherein the third tube has a length of between 4 mm and 6 mm.
Example 28:
The aerosol-generating article of Example 27, wherein the third tube has a thickness of 5 mm.
Example 29:
An aerosol-generating article according to any of the examples, comprising a ventilation zone.
Example 30:
30. The aerosol-generating article of Example 29, wherein the ventilation zone comprises one or more rows of ventilation perforations.
Example 31:
An aerosol-generating article as described in Example 30, wherein one or more rows of ventilation perforations are formed through the wall of at least one of the first tube, the second tube, and the third tube.
Example 32:
32. The aerosol-generating article of Example 31, wherein one or more rows of vent perforations are formed through the wall of the third tube.

Embodiments of the present invention will now be described, by way of example only, with reference to the following examples and accompanying drawings.

FIG. 1 shows a schematic exploded cross-sectional side view of a mouthpiece assembly for an aerosol-generating article according to the present invention. FIG. 2 shows a schematic cross-sectional side view of the mouthpiece assembly of FIG. FIG. 3 shows a schematic cross-sectional side view of a mouthpiece assembly for an aerosol-generating article according to the present invention. FIG. 4 shows a schematic cross-sectional side view of a mouthpiece assembly for an aerosol-generating article according to the present invention. FIG. 5 shows a schematic cross-sectional side view of an aerosol-generating article according to the present invention. FIG. 6 shows a schematic cross-sectional side view of an aerosol-generating article according to the present invention.

Some aerosol-generating articles heat, rather than burn, an aerosol-generating substrate, such as a tobacco-containing substrate. In such heated aerosol-generating articles, the aerosol is generated by the transfer of heat from a heat source to a physically separate aerosol-generating substrate or material, which may be located in contact with, within, around, or downstream of the heat source. During use of the aerosol-generating article, heat is transferred from the heat source to the aerosol-generating substrate, which may emit volatile compounds. These volatile compounds are entrained in air drawn through the aerosol-generating article by the user. As the emitted volatile compounds cool, they condense to form an aerosol. The aerosol may be inhaled by the user through the mouthpiece.

It would be desirable to provide an aerosol-generating article that can condense more of the emitted volatile compounds, thereby increasing the flow of aerosol through the mouthpiece. This could provide a better user experience.

Figures 1 and 2 schematically illustrate one embodiment of a mouthpiece assembly 110 for an aerosol-generating article 112 for generating an inhalable aerosol upon heating.

The mouthpiece assembly 110 has a downstream end 114 and an upstream end 116. The downstream end 114 of the mouthpiece assembly 110 is the end region of the mouthpiece assembly 110 toward which the aerosol flows after generation. The upstream end 116 of the mouthpiece assembly 110 is the end region of the mouthpiece assembly 110 opposite and/or distal from the downstream end 114. In some embodiments, the upstream end 116 of the mouthpiece assembly 110 is the end region of the mouthpiece assembly through which the generated aerosol flows before flowing through the downstream end 114.

In other words, during use, the generated aerosol flows from the upstream end 116 of the mouthpiece assembly 110 toward the downstream end 114 of the mouthpiece assembly 110.

In the embodiment shown in Figures 1 and 2, the mouthpiece assembly 110 includes a first tube 118, a second tube 120, and a third tube 122. As shown in Figures 1 and 2, in this embodiment, the second tube 120 is positioned between the first tube 118 and the third tube 122.

In this embodiment, the first tube 118, the second tube 120, and the third tube 122 are each formed from cellulose acetate. In other words, in the embodiment of Figures 1 and 2, the first tube 118, the second tube 120, and the third tube 122 are each cellulose acetate tubes.

In FIG. 1, the first tube 118, the second tube 120, and the third tube 122 are separated from one another. In FIG. 2, the first tube 118, the second tube 120, and the third tube 122 are provided in a configuration in which the first tube 118 and the third tube 122 abut the second tube 120, as will be described.

The first tube 118, the second tube 120, and the third tube 122 each have a downstream end face and an upstream end face. The downstream end faces of the tubes 118, 120, and 122 are the end faces that face toward the downstream end 114 of the mouthpiece assembly 10. The upstream end faces of the tubes 118, 120, and 122 are the end faces that face toward the upstream end 116 of the mouthpiece assembly 10.

The first tube 118 has a downstream end face 124 and an upstream end face 126. The second tube 120 has a downstream end face 128 and an upstream end face 130. The third tube 122 has a downstream end face 132 and an upstream end face 134.

In the embodiment shown in Figures 1 and 2, the first pipe 118 and the second pipe 120 are arranged so that the upstream end surface 124 of the first pipe 118 abuts the downstream end surface 126 of the second pipe 120.

In the embodiment shown in Figures 1 and 2, the second pipe 120 and the third pipe 122 are arranged so that the downstream end face 134 of the third pipe 122 abuts the upstream end face 128 of the second pipe 120.

In this embodiment, the first tube 118 abuts the second tube 120, and the third tube 122 abuts the second tube 120. In other embodiments, the first tube 118, the second tube 120, and the third tube 122 may be connected or attached to one another. The first tube 118, the second tube 120, and the third tube 122 may be attached to one another by, for example, one or more fastening elements or adhesive.

The first tube 118 may be considered the "mouthpiece" tube because, in use, the first tube 118 is the component of the mouthpiece assembly 110 that may come into contact with the user's mouth.

The second tube 120 may be considered a "venturi" tube because, as will be described, in use, the second tube 120 may provide a constriction in the flow path of the generated aerosol.

The third tube 122 may be considered a "diffuser" tube because, in use, the third tube 122 may provide space for the generated aerosol to combine with air.

The first tube 118 has a first tube inner diameter 136. The second tube has a second tube inner diameter 138. The third tube 122 has a third tube inner diameter 140. In the embodiment shown in Figures 1 and 2, the first tube 118, second tube 120, and third tube 122 each have a uniform inner diameter that is the same along the entire length of each tube.

The inner diameter of the first tube 118, the second tube 120, or the third tube 122 is understood to be the diameter or distance between the inner walls of the tube.

The inner diameter of the second tube 120 is smaller than the inner diameter of the first tube 118. In other words, the inner diameter 138 of the second tube is smaller than the inner diameter 136 of the first tube.

The inner diameter of the second tube 120 is smaller than the inner diameter of the third tube 122. In other words, the inner diameter 138 of the second tube is smaller than the inner diameter 140 of the third tube.

In some embodiments, such as the embodiment shown in Figures 1 and 2, the inner diameter of the first tube 118 is larger than the inner diameter of the third tube 122. In other words, in some embodiments, the inner diameter 136 of the first tube is larger than the inner diameter 140 of the third tube.

In the embodiment of the mouthpiece assembly 110 shown in Figures 1 and 2, the inner diameter 136 of the first tube is 4 mm, the inner diameter 138 of the second tube is 2.5 mm, and the inner diameter of the third tube is 3.5 mm.

In the embodiment of the mouthpiece assembly 110 shown in Figures 1 and 2, the first tube 118 has a length of 5 mm, the second tube 120 has a length of 5 mm, and the third tube 122 has a length of 5 mm.

Figure 3 schematically illustrates another embodiment of a mouthpiece assembly 210 for an aerosol-generating article 112 for generating an inhalable aerosol upon heating.

The embodiment of Figure 3 has the same components as the embodiment shown in Figures 1 and 2, and the components are numbered correspondingly.

However, the mouthpiece assembly 210 shown in Figure 3 has two differences from the mouthpiece assembly 110 shown in Figures 1 and 2.

First, in the mouthpiece assembly 210 of FIG. 3, the inner diameter of the first tube 118 is not uniform along its entire length. Instead, the inner diameter 136 of the first tube varies along the length of the first tube 118. The inner diameter of the first tube 118 increases from the upstream end surface 124 of the first tube 118 to the downstream end surface 126 of the first tube 118. In other words, in the embodiment shown in FIG. 3, the inner diameter 136 of the first tube is larger at the downstream end surface 126 of the first tube 118 than at the upstream end surface 124 of the first tube 118.

Second, in the mouthpiece assembly 210 of FIG. 3 , the inner diameter of the third tube 122 is not uniform along its entire length. Instead, the inner diameter 140 of the third tube 122 varies along the length of the third tube 122. The inner diameter of the third tube 122 decreases from the upstream end surface 132 of the third tube 122 to the downstream end surface 134 of the third tube 122. In other words, in the embodiment shown in FIG. 3 , the inner diameter 140 of the third tube 122 is smaller at the downstream end surface 134 of the third tube 122 than at the upstream end surface 132 of the third tube 122.

In the example of FIG. 3, the inner diameter of the first tube 118 is the average diameter or distance between the inner walls of the first tube 118. The inner diameter of the third tube 122 is the average diameter or distance between the inner walls of the third tube 122. The inner diameter of the second tube 120 is the diameter or distance between the inner walls of the second tube 120.

Figure 4 schematically illustrates another embodiment of a mouthpiece assembly 310 for an aerosol-generating article 112 for generating an inhalable aerosol upon heating.

The embodiment of Figure 4 has the same components as the embodiment shown in Figures 1 and 2, and the components are numbered correspondingly.

However, the mouthpiece assembly 310 shown in Figure 4 has differences relative to the mouthpiece assembly 110 shown in Figures 1 and 2.

In the mouthpiece assembly 310 of FIG. 4, the inner diameter of the first tube 118 is not uniform along its entire length. Instead, the inner diameter 136 of the first tube varies along the length of the first tube 118. The inner diameter of the first tube 118 increases from the upstream end surface 124 of the first tube 118 to the downstream end surface 126 of the first tube 118. In other words, in the embodiment shown in FIG. 4, the inner diameter 136 of the first tube is larger at the downstream end surface 126 of the first tube 118 than at the upstream end surface 124 of the first tube 118.

In the example of FIG. 4, the inner diameter of the first tube 118 is the average diameter or distance between the inner walls of the first tube 118. The inner diameter of the second tube 120 is the diameter or distance between the inner walls of the second tube 120. The inner diameter of the third tube 122 is the diameter or distance between the inner walls of the second tube 120.

Figure 5 schematically illustrates one embodiment of an aerosol-generating article 112. In the embodiment of Figure 5, the aerosol-generating article 112 includes a mouthpiece assembly 110, as shown schematically in Figures 1 and 2.

The aerosol-generating article 112 also includes an aerosol-forming substrate 142. The aerosol-forming substrate includes a vaporizable component for forming an aerosol. In the example of FIG. 5, the aerosol-forming substrate 142 is a liquid nicotine formulation. In other examples, the aerosol-forming substrate 142 may be a different formulation. In some examples, the aerosol-forming substrate 142 may be a gel formulation.

In the embodiment shown in FIG. 5, the aerosol-generating article 112 includes a fourth tube 144. The illustrated embodiment also includes a fifth tube 146. The fourth tube 144 is disposed concentrically with the first tube 118, the second tube 120, and the third tube 122. The fifth tube 146 is disposed concentrically with the first tube 118, the second tube 120, and the third tube 122.

In this embodiment, the fourth tube 144 is provided at the central openings of the third tube 122 and the fifth tube 146. In another embodiment, the fourth tube 144 may be provided only at the central opening of the third tube 122. The fourth tube 144 abuts the third tube 122 and the fifth tube 146. In another embodiment, the fourth tube 144 is attached to the third tube 122 and the fifth tube 146 by one or more fastening elements or adhesives.

In some embodiments, the fourth tube 144 may be formed from a material that is substantially impermeable to air. For example, the fourth tube 144 may be formed from cardboard.

In the embodiment shown in FIG. 5 , the fifth tube 146 abuts the third tube 122. In another embodiment, the third tube 122 and the fifth tube 146 may be connected or attached to one another. The third tube 122 and the fifth tube 146 may be attached to one another, for example, by one or more fastening elements or adhesive. The third tube 122 and the fifth tube 146 may be arranged such that the upstream end surface of the fifth tube 146 abuts the downstream end surface 132 of the third tube 122. In the embodiment shown in FIG. 5 , the fifth tube 146 has the same inner diameter as the third tube 122. Thus, the fifth tube 146 has an inner diameter of 3.5 mm. In another embodiment, the fifth tube 146 may have an inner diameter different from the inner diameter of the third tube 122.

In the embodiment of FIG. 5, a space 148 is defined within the aerosol-generating article 112. The space 148 is located between the fifth tube 146 and the aerosol-forming substrate 142. In embodiments that do not include the fifth tube 146, the space 148 may be defined between the third tube 122 and the aerosol-forming substrate 142. In some embodiments, the space 148 may provide an area that allows vaporized volatile compounds in the aerosol-forming substrate 142 to cool and nucleate into an aerosol.

The aerosol-generating article 112 shown in FIG. 5 also includes an upstream element 150. The upstream element 150 is positioned upstream of the aerosol-forming substrate 142. In this embodiment, the upstream element 150 abuts the aerosol-forming substrate 142. In the embodiment of FIG. 5, the upstream element 150 is an annular plug of fibrous filtration material. The upstream element 150 in FIG. 5 has a length of 5 mm. The RTD of the upstream element 150 in FIG. 5 is approximately 130 millimeters HO.

In the embodiment of FIG. 5, the aerosol-generating article 112 also includes a wrapper 152. The wrapper 152 is provided on the outer surface areas of the components of the aerosol-generating article 112. The wrapper 152 partially encapsulates at least some of the components of the aerosol-generating article 112. In this embodiment, the wrapper 152 partially encapsulates all of the components of the aerosol-generating article 112. As shown in FIG. 5, in some embodiments, the wrapper 152 completely encapsulates all of the components of the aerosol-generating article 112 except for the downstream end surface of the first tube 118 and the upstream end surface of the upstream element 150.

The embodiment of the aerosol-generating article 112 shown in FIG. 5 also includes a ventilation zone. The ventilation zone is provided at a location along the aerosol-generating article 112. In this embodiment, the ventilation zone is provided in the region of the third tube 122. In this embodiment, the ventilation zone is a circumferential row of perforations 154 formed through the wrapper 152 and the third tube 122. The perforations 154 allow air to flow from outside the aerosol-generating article 112, through the perforations 154, and into the opening defined by the third tube 122.

Figure 6 schematically illustrates an alternative embodiment of an aerosol-generating article 212. In the embodiment of Figure 6, the aerosol-generating article 212 includes the mouthpiece assembly 110 shown schematically in Figures 1 and 2.

In the embodiment of the aerosol-generating article 212 shown in FIG. 6, the configuration of the upstream end 116 differs from the configuration of the upstream end 116 of the embodiment of the aerosol-generating article 112 shown in FIG. 5, as will be described.

In the embodiment of FIG. 6, the upstream element 150 is positioned immediately upstream of and abuts the aerosol-forming substrate 142. The upstream element 150 comprises an annular plug comprising a fibrous filtration material. In this embodiment, the upstream element 150 comprises an annular plug of cellulose acetate surrounded by a rigid wrapper. In the embodiment of FIG. 6, the upstream element 150 has a length of 5 mm and an RTD of the upstream element 150 is 30 millimeters HO.

In the embodiment of FIG. 6, the aerosol-generating article 212 also includes a recess 156. The recess 156 extends from the upstream end 116 of the aerosol-generating article 212, through the upstream element 150, and through at least a portion of the aerosol-forming substrate 142.

The recess 156 is located along the central axis of the aerosol-generating article 212. In the example of FIG. 6, the recess 156 has a circular cross-sectional shape. In the example shown, the recess 156 extends the entire length of both the upstream element 150 and the aerosol-forming substrate 142 by passing through both the annular plug of fibrous filtration material of the upstream element 150 and the annular plug of porous medium of the aerosol-forming substrate 142. In this example, the recess 156 has a length of 15 mm, corresponding to the combined length of the upstream element 150 and the aerosol-forming substrate 142. In the example of FIG. 6, the recess has a diameter of 4 mm.

The aerosol-generating article 212 of FIG. 6 has a wrapper 152. The wrapper 152 is provided on the longitudinal inner surface of the recessed portion. The wrapper 152 extends the entire length of the recessed portion 156 and is provided on the entire longitudinal inner surface of the recessed portion 156.

In the embodiment shown in FIG. 6, the downstream end of the recess 156 is defined by the wrapper 152. This is achieved by mechanically folding the wrapper 152 at the downstream end of the recess 156.

The wrapper 152 extends from the upstream end of the recess 156 across the upstream end of the aerosol-generating article 212. The wrapper 152 also extends over the entire outer surface of the aerosol-generating article 212. In this manner, the wrapper 212 acts to connect the various components of the aerosol-generating article 212.

The wrapper 152 may include a cellulosic paper layer co-laminated with a layer of aluminum foil. In this embodiment, the wrapper 152 is disposed so that the paper layer is on the outer surface of the aerosol-generating article 212.

We now describe the use of the aerosol-generating article 112 shown in Figure 5.

In use, the aerosol-generating article 112 is inserted into the aerosol-generating device. When the aerosol-generating article 112 is in the inserted position within the aerosol-generating device, the heating element of the aerosol-generating device is adjacent to the aerosol-forming substrate 142. When the aerosol-generating device is activated, the heating element heats up. The increased temperature of the heating element heats the aerosol-forming substrate 142. Volatile compounds in the aerosol-forming substrate 142 then vaporize to form a vapor, which cools and nucleates into an aerosol in the space 148 between the fifth tube 146 and the aerosol-forming substrate 142.

When a user draws on (i.e., inhales from) the downstream end 114 of the aerosol-generating device 112, the resulting pressure change within the aerosol-generating device 112 causes air to be drawn through the perforations 154 and into the fourth tube 144. The air drawn into the aerosol-generating article 112 through the perforations 154 entrains aerosol from the space 148. The fourth tube 144 prevents the entrained aerosol from being lost into the structure of the third tube 122 or the fifth tube 146.

The aerosol-laden air then passes through the third tube 122 and into the second tube 120 due to the pressure regime inside the aerosol-generating article 112. The narrow inner diameter of the second tube 120 provides a Venturi effect, which compresses the aerosol-laden air while it is within the second tube 120.

When a user inhales into the downstream end 114 of the aerosol generating device 112, the aerosol-laden air then flows out the second tube 120 and into the first tube 118. As the aerosol-laden air is drawn from the second tube 120 into the tube 118, the larger diameter of the first tube 118 allows the air to expand and cool, thereby forming more droplets into the aerosol. The aerosol can then be inhaled by the user through the downstream end of the first tube 118.

In normal use of the aerosol-generating article 112, a user inhales the aerosol by engaging their mouth with the first tube 118 at the downstream end 114 of the aerosol-generating article 112. In the embodiment of FIG. 5, the first tube 118 is a tube formed from cellulose acetate, making the first tube 118 rigid and resilient, providing an improved user experience.

The first tube 118, which is formed from a rigid material such as cellulose acetate, also ensures that the user can properly handle the aerosol-generating article 112.

First tube 118, formed from a material that is substantially impermeable to water, such as cellulose acetate, is also less sensitive to moisture from the user's mouth.

For purposes of this specification and the appended claims, unless otherwise indicated, all numbers expressing amounts, quantities, percentages, and the like should be understood in all instances to be modified by the term "about." Also, all ranges include the disclosed maximum and minimum points, and include any intermediate ranges therein, which may or may not be specifically recited herein. Thus, in this context, the number A is understood as A ± 10%. Within this context, the number A may be considered to include values that are within the usual standard error for measurement of the property that the number A modifies. In some cases, such as when used in the appended claims, the number A may deviate by the percentages recited above, provided that the amount by which A deviates does not materially affect the basic and novel properties of the claimed invention. Also, all ranges include the disclosed maximum and minimum points, and include any intermediate ranges therein, which may or may not be specifically recited herein.

Claims (11)

1. An aerosol-generating article for producing an inhalable aerosol upon heating, said aerosol-generating article comprising:
a mouthpiece assembly including a first tube, a second tube, and a third tube, the mouthpiece assembly being located at a downstream end of the aerosol-generating article ;
an aerosol-forming substrate;
the first pipe abuts against a downstream end surface of the second pipe, and the third pipe abuts against an upstream end surface of the second pipe;
the first tube is located at a downstream end of the mouthpiece assembly;
the inner diameter of the second tube is smaller than the inner diameter of the first tube;
the inner diameter of the second tube is smaller than the inner diameter of the third tube;
the inner diameter of the first tube is between 3 mm and 8 mm;
the inner diameter of the second tube is greater than 1 mm;
a ratio of the inner diameter of the first tube to the inner diameter of the second tube is 1.2 to 5;
a ratio of the inner diameter of the first tube to the inner diameter of the third tube is 0.5 to 2;
An aerosol-generating article, wherein the second tube is a cellulose acetate tube. The aerosol-generating article of claim 1, wherein the inner diameter of the first tube is larger than the inner diameter of the third tube. The aerosol-generating article according to claim 1 or 2, wherein the first tube is a cellulose acetate tube. The aerosol-generating article according to any one of claims 1 to 3, wherein the third tube is a cellulose acetate tube. The aerosol-generating article according to any one of claims 1 to 4, wherein the ratio of the inner diameter of the third tube to the inner diameter of the second tube is 1.5 to 5. The aerosol-generating article described in any one of claims 1 to 5, wherein the first tube has an inner diameter of 4 mm. The aerosol-generating article according to any one of claims 1 to 6, wherein the second tube has an inner diameter of 1 mm to 3 mm. The aerosol-generating article according to any one of claims 1 to 7, wherein the third tube has an inner diameter of 3 mm to 8 mm. The aerosol-generating article according to any one of claims 1 to 8, which has a ventilation zone. The aerosol-generating article of claim 9, wherein the ventilation zone comprises one or more rows of ventilation perforations. The aerosol-generating article of claim 10, wherein the one or more rows of ventilation perforations are formed through the wall of at least one of the first tube, the second tube, and the third tube.