Patent Description:
Recently, the demand for alternative methods to overcome the shortcomings of traditional aerosol generating articles (cigarettes) has increased. For example, there is growing demand for a method of generating aerosol by heating an aerosol generating material in aerosol generating articles, rather than by combusting aerosol generating articles.

An aerosol generating article includes a filter segment, and the filter segment filters out a particular component included in aerosol or cools the aerosol. The filter segment may allow the aerosol to be easily inhaled by user smoking, while at the same time filtering out particular components of the aerosol. Therefore, studies have been conducted to develop a filter segment having appropriate suction resistance. <CIT> relates to an aerosol generating apparatus and a cradle for receiving the same, the aerosol generating apparatus comprising: a cigarette insertion part into which a cigarette can be inserted; and a vaporizer which generates aerosol by heating a liquid composition and discharges the generated aerosol towards the inserted cigarette so that the generated aerosol passes through the cigarette that has been inserted into the cigarette insertion part. <CIT> relates to a filter tip having a core part, a channeled tape arranged around the core part and a roll paper formed on the circumference of the tape and provided with a filter element provided with a void part communicating in the longitudinal direction of a filter between the tape and the roll paper and a filter element composed of a fibrous material. The void part amounts to <NUM>-<NUM>% of the sectional area of the filter element. <CIT> relates to a suction end filter portion comprising a central filter plug having an outer surface and a peripheral region arranged around the outer surface of the central filter plug; and an outer portion arranged around the peripheral region of the suction end filter portion. <CIT> relates to a tobacco smoke filter or filter element comprising a stiff outer wrapper engaged around a downstream thermoformed core of tobacco smoke filtering material and a further core longitudinally aligned therewith; the downstream thermoformed core having a profiled outer surface which defines with the stiff outer wrapper at least one longitudinally extending channel which extends the length of the downstream core.

<CIT> relates to an aerosol generating article having two separate filters upstream and downstream of the aerosol generating substance.

Provided is an aerosol generating article including a filter segment at its end, which includes a channel such that suction resistance of the aerosol generating article may be adjusted according to a cross-sectional area of the channel.

The problem is solved by the features of the independent claim.

According to an aspect of the present disclosure, an aerosol generating article may include: a front-end filter segment arranged at an upstream end that is to be inserted into an aerosol generating device; a rear-end filter segment arranged at a downstream end that is to contact a mouth of a user; and a tobacco rod arranged between the front-end filter segment and the rear-end filter segment, wherein at least one filter segment of the front-end filter segment and the rear-end filter segment includes: at least one channel extending from the upstream end toward the downstream end; and a filter structure filtering out some components of aerosol, wherein the at least one filter segment has suction resistance corresponding to a ratio between a cross-sectional area of the at least one channel and a cross-sectional area of the filter structure.

Suction resistance of an aerosol generating article may be adjusted by adjusting a ratio (porosity) of a cross-sectional area of a channel to a cross-sectional area of a filter structure. Also, an aerosol may be easily passed through a channel formed in a filter segment while simultaneously filtering out components of the aerosol through a filter structure.

Effects of the aerosol generating article are not limited by the examples described above, and more various effects are included herein.

According to an aspect of the present disclosure, an aerosol generating article may include: a front-end filter segment arranged at an upstream end that is to be inserted into an aerosol generating device; a rear-end filter segment arranged at a downstream end that is to contact a mouth of a user; and a tobacco rod arranged between the front-end filter segment and the rear-end filter segment, wherein at least one filter segment of the front-end filter segment and the rear-end filter segment includes: at least one channel extending from the upstream end toward the downstream end; and a filter structure filtering out some components of an aerosol, wherein the at least one filter segment has a suction resistance corresponding to a ratio between a cross-sectional area of the at least one channel and a cross-sectional area of the filter structure.

The at least one filter segment may have a suction resistance within a range of <NUM> mmWG/mm to <NUM> mmWG/mm.

The ratio of the cross-sectional area of the at least one channel to the cross-sectional area of the filter structure may have a value within a range of <NUM> to <NUM>.

A cross-sectional shape of the at least one channel may be a circular or multi-leaf shape.

The at least one channel may include a plurality of channels, wherein the plurality of channels are arranged between the filter structure and a wrapper surrounding the at least one filter segment, and the filter structure includes a plurality of leg portions that extend from the center of the filter structure between the plurality of channels.

The at least one channel may include a plurality of channels, wherein the plurality of channels are different in at least one of a location, a cross-sectional shape, and a cross-sectional area.

A cross-sectional area of the at least one channel at one point may be different from a cross-sectional area of the at least one channel at another point.

An area of an upstream-end opening of the at least one channel may be greater than an area of a downstream-end opening of the at least one channel.

A normal of an opening of the at least one channel may meet the filter structure.

At least one channel formed in the front-end filter segment and at least one channel formed in the rear-end filter segment may be different in at least one of a cross-sectional shape, a cross-sectional area, and a number.

According to another aspect of the present disclosure, an aerosol generating article may include: a tobacco rod arranged at an upstream end that is to be inserted into an aerosol generating device; and a rear-end filter segment arranged at a downstream end that is to contact a mouth of a user, wherein the rear-end filter segment includes: at least one channel extending from the upstream end toward the downstream end; and a filter structure filtering out some components of an aerosol, wherein the at least one filter segment has a suction resistance corresponding to a ratio between a cross-sectional area of the at least one channel and a cross-sectional area of the filter structure.

In addition, in certain cases, a term which is not commonly used may be selected.

In the following embodiments, with respect to the terms "upstream" and "downstream", when a user draws air by using a smoking article, a portion where air is introduced into an aerosol generating article from the outside is "upstream" and a portion where air is discharged from an inside of the aerosol generating article to the outside is "downstream". The terms "upstream" and "downstream" are terms used to indicate relative locations or orientations between segments constituting an aerosol generating article.

In the following embodiments, the term "longitudinal direction" indicates a longitudinal direction of an aerosol generating article, and the term "diameter direction" indicates a shortening direction of the aerosol generating article. In other words, the "diameter direction" refers to a direction perpendicular to the "longitudinal direction".

<FIG> are diagrams showing examples in which an aerosol generating article is inserted into an aerosol generating device.

Referring to <FIG>, the aerosol generating device <NUM> may include a battery <NUM>, a controller <NUM>, and a heater <NUM>. Referring to <FIG> and <FIG>, the aerosol generating device <NUM> may further include a vaporizer <NUM>. Also, the aerosol generating article <NUM> may be inserted into an inner space of the aerosol generating device <NUM>.

<FIG> illustrates that the battery <NUM> the controller <NUM>, and the heater <NUM> are arranged in series.

When the aerosol generating article <NUM> is inserted into the aerosol generating device <NUM>, the aerosol generating device <NUM> may operate the heater <NUM> and/or the vaporizer <NUM> to generate an aerosol. The aerosol generated by the heater <NUM> and/or the vaporizer <NUM> is delivered to a user by passing through the aerosol generating article <NUM>.

The controller <NUM> may control overall operations of the aerosol generating device <NUM>.

For example, when the aerosol generating article <NUM> is inserted into the aerosol generating device <NUM>, the heater <NUM> may be located inside or outside the aerosol generating article <NUM>. Thus, the heated heater <NUM> may increase a temperature of an aerosol generating material in the aerosol generating article <NUM>.

In detail, the heater <NUM> may include an electrically conductive coil for heating an aerosol generating article in an induction heating method, and the aerosol generating article may include a susceptor which may be heated by the induction heater.

For example, the heater <NUM> may include a tube-type heating element, a plate-type heating element, a needle-type heating element, or a rod-type heating element, and may heat the inside or the outside of the aerosol generating article <NUM>, according to the shape of the heating element.

Here, the plurality of heaters <NUM> may be inserted into the aerosol generating article <NUM> or may be arranged outside the aerosol generating article <NUM>. Also, some of the plurality of heaters <NUM> may be inserted into the aerosol generating article <NUM> and the others may be arranged outside the aerosol generating article <NUM>.

The vaporizer <NUM> may generate aerosol by heating a liquid composition and the generated aerosol may pass through the aerosol generating article <NUM> to be delivered to a user. In other words, the aerosol generated via the vaporizer <NUM> may move along an air flow passage of the aerosol generating device <NUM> and the air flow passage may be configured such that the aerosol generated via the vaporizer <NUM> passes through the aerosol generating article <NUM> to be delivered to the user.

The aerosol generating device <NUM> may further include general-purpose components in addition to the battery <NUM>, the controller <NUM>, the heater <NUM>, and the vaporizer <NUM>. For example, the aerosol generating device <NUM> may include a display capable of outputting visual information and/or a motor for outputting haptic information. Also, the aerosol generating device <NUM> may include at least one sensor. Also, the aerosol generating device <NUM> may be formed as a structure where, even when the aerosol generating article <NUM> is inserted into the aerosol generating device <NUM>, external air may be introduced or internal air may be discharged.

Alternatively, the heater <NUM> may be heated while the cradle and the aerosol generating device <NUM> are coupled to each other.

The aerosol generating article <NUM> may be similar to a general combustive aerosol generating article. For example, the aerosol generating article <NUM> may be divided into a first portion including an aerosol generating material and a second portion including a filter, etc. The second portion of the aerosol generating article <NUM> may also include an aerosol generating material. For example, an aerosol generating material made in the form of granules or capsules may be inserted into the second portion.

Alternatively, only a portion of the first portion may be inserted into the aerosol generating device <NUM>. Otherwise, the entire first portion and a portion of the second portion may be inserted into the aerosol generating device <NUM>.

For example, the external air may flow into at least one air passage formed in the aerosol generating device <NUM>. For example, opening and closing of the air passage and/or a size of the air passage may be adjusted by the user. Accordingly, the amount and quality of vapor may be adjusted by the user. As another example, the external air may flow into the aerosol generating article <NUM> through at least one hole formed in a surface of the aerosol generating article <NUM>.

Hereinafter, an example of the aerosol generating article <NUM> will be described with reference to <FIG>.

Referring to <FIG>, the aerosol generating article <NUM> may include a tobacco rod <NUM> and a filter rod <NUM>. The first portion described above with reference to <FIG> may include the tobacco rod <NUM>, and the second portion may include the filter rod <NUM>.

The aerosol generating article <NUM> may have a diameter within a range of about <NUM> to about <NUM> and a length of about <NUM>, but an embodiment is not limited thereto. For example, a length of the tobacco rod <NUM> may be about <NUM>, a length of a first filter segment <NUM> may be about <NUM>, a length of a second filter segment <NUM> may be about <NUM>, and a length of a third filter segment <NUM> may be about <NUM>, but embodiments are not limited thereto.

The aerosol generating article <NUM> may be packaged by wrappers <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>. For example, the tobacco rod <NUM> may be wrapped by the wrapper <NUM>, and the filter rod <NUM> may be packaged by the wrappers <NUM>, <NUM>, and <NUM>. Also, the tobacco rod <NUM> and the filter rod <NUM> wrapped by the wrappers <NUM>, <NUM>, <NUM>, and <NUM> may be coupled to each other, and the entire aerosol generating article <NUM> may be repackaged by the wrapper <NUM>.

The first filter segment <NUM> may be a cellulose acetate filter. For example, the first filter segment <NUM> may be a tube-type structure having a hollow inside. In other words, the first filter segment <NUM> may include a hollow having a first diameter, and the hollow may function as a channel through which aerosol passes. The length of the first filter segment <NUM> may be an appropriate length within a range of about <NUM> to about <NUM>, but is not limited thereto. Alternatively, the length of the first filter segment <NUM> may be <NUM>, but is not limited thereto. A diameter of the hollow included in the first filter segment <NUM> may be an appropriate diameter within a range of about <NUM> to about <NUM>, but is not limited thereto.

The second filter segment <NUM> cools the aerosol that is generated as the heater <NUM> heats the tobacco rod <NUM>. Therefore, a user may puff the aerosol that is cooled at an appropriate temperature.

The second filter segment <NUM> may cool the aerosol by a phase change action. For example, a material forming the second filter segment <NUM> may perform a phase change action that requires absorption of heat energy, such as melting or glass transition. As an endothermic reaction occurs at a temperature at which the aerosol enters the second filter segment <NUM>, a temperature of the aerosol passing through the second filter segment <NUM> is lowered.

The length or diameter of the second filter segment <NUM> may be variously determined according to a shape of the aerosol generating article <NUM>. For example, the length of the second filter segment <NUM> may be an appropriate length within a range of about <NUM> to about <NUM>. Preferably, the length of the second filter segment <NUM> may be about <NUM> but is not limited thereto.

As an example, the second filter segment <NUM> may be formed of a polymer material or a biodegradable polymer material alone. Here, examples of the polymer material may include, but are not limited to, gelatin, polyethylene (PE), polypropylene (PP), polyurethane (PU), fluorinated ethylene propylene (FEP), and combinations thereof. Also, examples of the biodegradable polymer material may include, but are not limited to, polylactic acid (PLA), polyhydroxybutyrate (PHB), cellulose acetate, poly-epsilon-caprolactone (PCL), polyglycolic acid (PGA), polyhydroxyalkanoate (PHAs), and starch-based thermoplastic resin.

In detail, the second filter segment <NUM> may be formed of pure polylactic acid alone. For example, the second filter segment <NUM> may have a three-dimensional structure manufactured by using one or more fiber strands (hereinafter referred to as fiber strands) formed of pure polylactic acid. Here, the thickness, length, number, and shape of the fiber strands constituting the second filter segment <NUM> may vary. As the second filter segment <NUM> is formed of pure polylactic acid, unintended materials may be prevented from being generated while the aerosol passes through the second filter segment <NUM>.

A rear-end filter segment <NUM> is arranged at a rear end contacting the user's mouth during smoking. A length of the rear-end filter segment <NUM> may be an appropriate length within a range of about <NUM> to about <NUM>. For example, the length of the rear-end filter segment <NUM> may be about <NUM> but is not limited thereto.

In a process of manufacturing the rear-end filter segment <NUM>, a flavored liquid may be sprayed onto the rear-end filter segment <NUM> such that a flavor may be generated by the rear-end filter segment <NUM>. Alternatively, an additional fiber coated with a flavored liquid may be inserted into the rear-end filter segment <NUM>. The aerosol generated in the tobacco rod <NUM> is cooled by passing through the second filter segment <NUM>, and the cooled aerosol is delivered to the user through the rear-end filter segment <NUM>. Therefore, by adding a flavoring element to the rear-end filter segment <NUM>, an effect of enhancing the persistence of a flavor delivered to the user may be achieved.

Also, the rear-end filter segment <NUM> may include at least one capsule <NUM>. Here, the capsule <NUM> may have a configuration in which a content liquid including a flavoring material is wrapped with a film. For example, the capsule <NUM> may have a spherical or cylindrical shape.

Another example of an aerosol generating article <NUM> will now be described with reference to <FIG>.

Referring to <FIG>, the aerosol generating article <NUM> includes a front-end filter segment <NUM>, a tobacco rod <NUM>, an intermediate filter segment <NUM>, and a rear-end filter segment <NUM>. The first portion described above with reference to <FIG> may include the front-end filter segment <NUM> and the tobacco rod <NUM>, and the second portion may include the intermediate filter segment <NUM> and the rear-end filter segment <NUM>.

The aerosol generating article <NUM> may be packaged by at least one wrapper <NUM>. The wrapper <NUM> may have at least one hole through which external air may be introduced or internal air may be discharged. For example, the front-end filter segment <NUM> may be packaged by a first wrapper <NUM>, the tobacco rod <NUM> may be packaged by a second wrapper <NUM>, the intermediate filter segment <NUM> may be packaged by a third wrapper <NUM>, and the rear-end filter segment <NUM> may be packaged by a fourth wrapper <NUM>. Also, the entire aerosol generating article <NUM> may be repackaged by a fifth wrapper <NUM>.

The tobacco rod <NUM> may correspond to the tobacco rod <NUM> described above with reference to <FIG>. Therefore, hereinafter, the detailed description of the tobacco rod <NUM> will be omitted.

The front-end filter segment <NUM> is arranged toward the tobacco rod <NUM> at an upstream end of the aerosol generating article <NUM> that is inserted into the aerosol generating device <NUM>. The front-end filter segment <NUM> may prevent a liquefied aerosol from flowing into the aerosol generating device <NUM> of <FIG> from the tobacco rod <NUM> during smoking.

A length or diameter of the front-end filter segment <NUM> may be variously determined according to a shape of the aerosol generating article <NUM>. For example, the length of the front-end filter segment <NUM> may be an appropriate length within a range of about <NUM> to about <NUM>. Preferably, the length of the front-end filter segment <NUM> may be about <NUM> but is not limited thereto. For example, the diameter of the front-end filter segment <NUM> may be an appropriate diameter within a range of about <NUM> to about <NUM>. Preferably, the diameter of the front-end filter segment <NUM> may be about <NUM> but is not limited thereto.

The intermediate filter segment <NUM> may be a cellulous acetate filter. For example, the intermediate filter segment <NUM> may be a tube-type structure having a hollow inside. In other words, the intermediate filter segment <NUM> may include a hollow having a first diameter, and the hollow may function as a channel through which aerosol passes. A length of the intermediate filter segment <NUM> may be an appropriate length within a range of about <NUM> to about <NUM> but is not limited thereto. Preferably, the length of the intermediate filter segment <NUM> may be <NUM> but is not limited thereto. The diameter of the hollow included in the intermediate filter segment <NUM> may be an appropriate diameter within a range of about <NUM> to about <NUM> but is not limited thereto.

The rear-end filter segment <NUM> is arranged at a rear end contacting the user's mouth during smoking. A length of the rear-end filter segment <NUM> may be an appropriate length within a range of about <NUM> to about <NUM>. For example, the length of the rear-end filter segment <NUM> may be about <NUM> but is not limited thereto.

In a manufacturing the rear-end filter segment <NUM>, a flavoring liquid may be sprayed onto the rear-end filter segment <NUM> such that a flavor may be generated by the rear-end filter segment <NUM>. Alternatively, an additional fiber coated with a flavored liquid may be inserted into the rear-end filter segment <NUM>.

In an aerosol generating article as described above, the rear-end filter segment <NUM> illustrated in <FIG>, the front-end filter segment <NUM>, and the rear-end filter segment <NUM> illustrated in <FIG> may have appropriate suction resistances to thereby allow aerosol to be easily puffed by the user while filter out components of the aerosol. To this end, the front-end filter segment <NUM> and the rear-end filter segments <NUM> and <NUM> may include at least one channel formed from an upstream end toward a downstream end and a filter structure filtering out components of an aerosol.

<FIG> illustrates an example of a lateral cross section of a filter segment including a filter structure and a channel. In other words, <FIG> illustrates an example of a lateral cross section of the front-end filter segment <NUM> or the rear-end filter segments <NUM> and <NUM> illustrated in <FIG> and <FIG>.

A filter structure <NUM> may be an element for filtering out some components of aerosol and may be formed of cellulose acetate.

The suction resistance of a filter segment may be adjusted by adjusting mono denier, total denier, a plasticizer content, and the like of cellulose acetate tow used for the filter structure <NUM>. However, in this method, structural defects such as recesses may occur in acquiring appropriate suction resistance.

Front-end and rear-end filter segments may include a channel <NUM> to achieve appropriate suction resistance. The channel <NUM> passes aerosol generated in a tobacco rod or a vaporizer without filtering, and suction resistance decreases as a cross-sectional area of the channel <NUM> increases. In contrast, the filter structure <NUM> may inhibit a flow of the aerosol, and the suction resistance increases as a cross-sectional area of the filter structure <NUM> increases. Therefore, appropriate suction resistance may be acquired by adjusting a ratio of cross-sectional areas between a channel and a filter structure.

In an embodiment, front-end and rear-end filter segments may have suction resistance corresponding to a ratio of cross-sectional areas between a channel and a filter structure. For example, a ratio (porosity) of a cross-sectional area of a channel to a cross-sectional area of a filter structure may be within a range of about <NUM> to about <NUM>. Preferably, the porosity may be included within a range of about <NUM> to about <NUM>. The suction resistance of front-end and rear-end filter segments may be within a range of about <NUM> mmWG/mm to about <NUM> mmWG/mm according to porosity. Preferably, the suction resistance may be included within a range of about <NUM> mmWG/mm to about <NUM> mmWG/mm. More preferably, the suction resistance may be <NUM> mmWG/mm.

In addition to that illustrated in <FIG>, a channel of the front-end and rear-end filter segments may have a different location, cross-sectional shape, and number.

For example, a channel may be formed to have a three-leaf cross section as illustrated in <FIG> or a four-leaf cross section as illustrated in <FIG>. The shape of the channel is not limited to the illustrated types, and the channel may be formed in various shapes such as a multi-leaf cross section, a polygonal shape, a heart shape, and a water droplet shape.

Channels illustrated in <FIG> are formed to be located in the centers of front-end and rear-end filter segments. However, a channel may be formed to be located close to sides of segments, and locations where the channel is formed are not limited.

As another example, as illustrated in <FIG>, a plurality of channels <NUM> may be formed in the front-end and rear-end filter segments. <FIG> illustrate that four or more channels are formed, but the number of channels <NUM> may be two or more.

The plurality of channels <NUM> may be formed radially in the front-end and rear-end filter segments. For example, the plurality of channels <NUM> may be formed near a central portion as illustrated in <FIG> or may be formed near a side as illustrated in <FIG> and <FIG>. Alternatively, as illustrated in <FIG>, the plurality of channels <NUM> may be formed at random locations without rules.

Alternatively, as illustrated in <FIG>, the plurality of channels <NUM> may be arranged between a filter structure <NUM> and a wrapper surrounding the front-end and rear-end filter segments. As illustrated in <FIG>, the filter structure <NUM> may include a plurality of leg portions that face outwards from the center of the filter structure <NUM> and extend between the plurality of channels <NUM>. In other words, a cross-sectional shape of the filter structure <NUM> may be a kind of sawtooth shape. <FIG> illustrates seven channels <NUM> and seven leg portions, but a filter segment may include fewer or more than seven channels <NUM> and leg portions of the filter structure <NUM>. A filter segment illustrated in <FIG> may be a front-end filter segment.

Also, the plurality of channels <NUM> may be formed in a circular shape as illustrated in <FIG> or may be formed in a fan shape as illustrated in <FIG>. Alternatively, the plurality of channels <NUM> may be formed in irregular shapes as illustrated in <FIG>. The shape of a plurality of channels is not limited to the illustrated types.

Also, as illustrated in <FIG>, the plurality of channels <NUM> may be formed to have the same cross-sectional area. Alternatively, as illustrated in <FIG>, the plurality of channels <NUM> may be formed to have different cross-sectional areas.

As described above, the suction resistance of an aerosol generating article may be adjusted by adjusting a ratio (porosity) of a cross-sectional area of a channel to a cross-sectional area of a filter structure. To embody desired suction resistance, various shapes, areas, and numbers of channels may be employed, and an aerosol path may be adjusted by adjusting locations of the front-end and rear-end filter segments.

A longitudinal cross section of a channel in a longitudinal direction will now be described.

<FIG> illustrates an example of a longitudinal cross section of a filter segment including a filter structure and a channel. In other words, <FIG> illustrates an example of a longitudinal cross section of the front-end filter segment <NUM> or the rear-end filter segments <NUM> and <NUM> illustrated in <FIG> and <FIG>.

A channel <NUM> may be formed parallel to a longitudinal direction. In other words, a boundary line between the channel <NUM> and a filter structure <NUM> may be formed to be parallel to the longitudinal direction, and the channel <NUM> may be formed to have a constant width.

A ratio of a width W1 of the channel <NUM> to a diameter W2 of a filter segment may be included within a range of about <NUM> to about <NUM>. Alternatively, the ratio of the width W1 of the channel <NUM> to the diameter W2 of the filter segment may be included within a range of about <NUM> to about <NUM> but is not limited to the above range. For example, when the diameter W2 of the filter segment is <NUM>, the width W1 of the channel <NUM> may be included within a range of about <NUM> to about <NUM> or a range of about <NUM> to about <NUM>.

Also, the channel <NUM> may be formed such that a cross-sectional area thereof at one point is different from a cross-sectional area thereof at another point. For example, as illustrated in <FIG>, a longitudinal cross sectional of a channel <NUM> may have a tapered shape, and a cross-sectional area of the channel <NUM> may gradually increase toward the longitudinal direction.

Also, as illustrated in <FIG>, an area of the opening <NUM> at the upstream end of the channel <NUM> may be larger than an area of the opening <NUM> at the downstream end. The front-end filter segment <NUM> illustrated in <FIG> may allow aerosol to easily flow downstream during smoking, prevent the tobacco rod <NUM> from being detached, and prevent the liquefied aerosol from flowing into the aerosol generating device <NUM> of <FIG> from the tobacco rod <NUM> during smoking. Therefore, the area of the upstream-end opening <NUM> may be formed larger such that the aerosol may be easily introduced into the channel <NUM>. Also, the area of the downstream-end opening <NUM> may be formed smaller to prevent the tobacco rod <NUM> from being detached and prevent the liquefied aerosol from flowing into the aerosol generating device <NUM>.

Alternatively, as illustrated in <FIG>, a channel <NUM> may be formed such that a normal <NUM> of a channel opening <NUM> meets a filter structure <NUM>. In other words, the channel <NUM> may be formed obliquely with respect to a longitudinal direction. When the channel <NUM> is formed as described above in consideration of the function of the front-end filter segment <NUM> illustrated in <FIG>, even if the tobacco rod <NUM> or a liquefied aerosol is introduced in the direction of a normal of openings <NUM> and <NUM>, the tobacco rod <NUM> or the liquefied aerosol may be blocked by the filter structure <NUM>. Therefore, the tobacco rod <NUM> or the liquefied aerosol may be prevented from being discharged into the aerosol generating device <NUM> of <FIG>.

<FIG> illustrates an example of an aerosol generating article including a channel formed in a rear-end filter segment. <FIG> illustrates an aerosol generating article in which a plurality of channels of <FIG> are formed in a rear-end filter segment of <FIG>.

When a user puffs while holding the rear-end filter segment <NUM> by the mouth of the user, aerosol formed in the tobacco rod <NUM> or a vaporizer passes through the rear-end filter segment <NUM> and is delivered to the user. In an embodiment, suction resistance that enables the user to easily puff aerosol may be acquired by forming a plurality of channels <NUM> having appropriate cross-sectional areas in the rear-end filter segment <NUM>. Also, a movement path of the aerosol may be controlled by allowing the aerosol to naturally flow along the plurality of channels <NUM> formed close to a side. Similarly, a plurality of channels may also be formed in the rear-end filter segment <NUM> illustrated in <FIG>.

<FIG> illustrates an example of an aerosol generating article in which a channel is formed in a front-end filter segment. <FIG> illustrates an aerosol generating article in which a channel of <FIG> is formed in a front-end filter segment of <FIG>.

When a user starts smoking, aerosol flows downstream, but some of liquefied aerosol may leak upstream. A front-end filter segment <NUM> may be arranged at the upstream side of a tobacco rod <NUM> to thereby prevent the tobacco rod <NUM> from being detached and prevent liquefied aerosol from flowing into the aerosol generating device <NUM>. Also, a channel <NUM> may be formed in the front-end filter segment <NUM> to embody appropriate suction resistance for a user to puff aerosol generated in the vaporizer <NUM> of <FIG> and <FIG>.

<FIG> illustrates an example of an aerosol generating article in which channels are formed in a front-end filter segment and a rear-end filter segment. <FIG> illustrates an aerosol generating article in which a channel of <FIG> is formed in a front-end filter segment of <FIG> while channels of <FIG> are formed in a rear-end filter segment.

Claim 1:
An aerosol generating article (<NUM>, <NUM>, <NUM>) comprising:
a front-end filter segment (<NUM>) arranged at an upstream end of the aerosol generating article (<NUM>,<NUM>,<NUM>) and which is to be inserted into an aerosol generating device (<NUM>);
a rear-end filter segment (<NUM>, <NUM>) arranged at a downstream end of the aerosol generating article (<NUM>,<NUM>,<NUM>) and which is to contact a mouth of a user; and
a tobacco rod (<NUM>, <NUM>) arranged between the front-end filter segment (<NUM>) and the rear-end filter segment (<NUM>, <NUM>),
wherein the front-end filter segment (<NUM>) comprises:
at least one channel (<NUM>) extending from the upstream end toward the downstream end of the front end filter segment (<NUM>); and
a filter structure (<NUM>) configured to prevent liquefied aerosol from flowing into the aerosol generating device (<NUM>), and
wherein the front-end filter segment has suction resistance corresponding to a ratio between a cross-sectional area of the at least one channel (<NUM>) and a cross-sectional area of the filter structure (<NUM>).