RU2774266C2 - Multi-segment component for aerosol-generating product - Google Patents

Abstract

FIELD: aerosol generating products.

SUBSTANCE: invention relates to a multi-segment component for an aerosol generating product. The multi-segment component comprises a combustible heat source, an aerosol-forming substrate located downstream of the combustible heat source, and a wrapper surrounding the combustible heat source along at least a portion of its length. An inflatable layer is provided between the combustible heat source and the wrapper and surrounds the combustible heat source, wherein the inflatable layer is formed from an intumescent inorganic adhesive.

EFFECT: invention makes it possible to improve the retention of the combustible heat source in the wrapper.

27 cl, 5 dwg, 5 ex

Description

The present invention relates to a multi-segment component for an aerosol generating article. In particular, the present invention relates to multi-segment components comprising a combustible heat source for heating an aerosol forming substrate located downstream of the combustible heat source, and a wrapper surrounding at least the back of the combustible heat source. The present invention also relates to combustible heat sources for such multi-segment components and to aerosol generating articles containing such multi-segment components.

A number of smoking articles have been proposed in the prior art in which tobacco is heated rather than burned. The purpose of such "heated" smoking articles is to reduce the known harmful smoke constituents resulting from the combustion and pyrolytic degradation of tobacco in conventional cigarettes. In one known type of heated smoking article, the aerosol is generated by the transfer of heat from a combustible heat source to a physically separated aerosol-forming substrate, such as a tobacco-containing substrate. The aerosol forming substrate may be located within, around, or downstream of the combustible heat source. During smoking, volatile compounds are released from the aerosol-forming substrate by heat transfer from the combustible heat source and are entrained in air drawn through the smoking article. When the released compounds are cooled, they condense to form an aerosol that is inhaled by the user.

For example, WO 2009/022232 A2 discloses a smoking article comprising a combustible heat source, an aerosol forming substrate located downstream of the combustible heat source, and a heat transfer member surrounding and in contact with the rear of the combustible heat source and adjacent the front part of the substrate that forms the aerosol. The combustible heat source and the aerosol-forming substrate abut each other in coaxial alignment and, together with the heat transfer member, is wrapped with a low air permeability cigarette paper outer wrapper to hold the various components of the smoking article together. In use, the front part of the aerosol-forming substrate is heated mainly by heat transfer through the back part of the combustible heat source and the heat transfer element abutting against it.

Devices and methods for the manufacture of multi-component aerosol generating articles are known in the art. For example, EP 2210509 A1 discloses a linear process for combining the components of a smoking article, such as a heat source, an aerosol generating substrate, an expansion chamber, to produce smoking articles without a filter. The method includes feeding a stream of components along a moving delivery path; compacting the stream of components into groups of two or more different components, wrapping the components in a web of material; and cutting the web of material at each interval between groups of components to form multi-segment components containing all components of the smoking article except for the mouthpiece. Multi-segment components, or unfiltered smoking articles, are then attached to single mouthpieces by wrapping the unfiltered smoking article and mouthpiece with tipping paper in a gluing machine to form the finished smoking article.

In another example, WO 2013/164124 A1 discloses the flow of first multi-segment components formed using a method similar to that described in EP 2210509 A1, each containing a combustible heat source, an aerosol-forming substrate, and a segment for directing the flow air into the receiving device and supplying a stream of second multi-segment components, each of which contains a mouthpiece and at least one additional segment, into the receiving device. The first multi-segment component is combined with the second multi-segment component by wrapping the first multi-segment component and the second multi-segment component with a web of material to form a separate smoking article containing a combustible heat source at the first end and a mouthpiece at the second end.

In aerosol-generating articles in which the aerosol-generating substrate, such as tobacco, is heated rather than burned, the temperature obtained in the aerosol-generating substrate significantly affects the ability to generate aerosol perceptible to the senses. It is generally desirable to maintain the temperature of the aerosol generating substrate within a certain range in order to optimize the delivery of the aerosol to the user. In some cases, the combustible heat source may be displaced in such a way that its position relative to the aerosol-forming substrate changes. Because of this, the temperature of the aerosol-forming substrate may be outside the desired range, thereby affecting the performance of the smoking article. If the temperature of the aerosol generating substrate falls too low, for example, the consistency and amount of aerosol delivered to the user can be adversely affected.

It would be desirable to provide a multi-segment component for an aerosol generating article containing a combustible heat source with improved containment.

According to the present invention, a multi-segment component is provided for an aerosol generating article, the multi-segment component comprising: a combustible heat source; an aerosol-forming substrate downstream of the combustible heat source; and a wrapper surrounding the combustible heat source along at least a portion of its length; wherein the multi-segment component further comprises an intumescent layer disposed between the combustible heat source and the wrapper and surrounding the combustible heat source, the intumescent layer being formed from the intumescent inorganic adhesive. The bulging inorganic adhesive can expand when heated during combustion of a combustible heat source.

Advantageously, in exemplary aspects of the invention, improved retention of the combustible heat source in the wrap can be achieved. Retention can be improved, for example, during combustion or after combustion of the combustible heat source, compared to those cases where there is no bulging inorganic adhesive. This may help or ensure that the combustible heat source is positioned correctly for the desired properties of the aerosol. Preferably, the presence of the inflatable inorganic adhesive affects the retention of the combustible heat source in the wrapper or improves the retention of the combustible heat source in the wrapper, as compared to an example in which the intumescent inorganic adhesive is absent. Because the intumescent layer is formed from an intumescent inorganic adhesive, there may be little or no loss of material or volume during combustion of the heat source. In some cases, there may not be a significant reduction in adhesion between the blistering inorganic adhesive and the combustible heat source.

The bulging inorganic adhesive may or may not form a bond with one or more surfaces with which it is in contact.

The presence of the blister layer may improve or ensure that the heat source is tightly held within the wrap during use. The additional inflatable layer may expand to compensate for any gap between the combustible heat source and the wrapper, for example as a result of thermal expansion of the wrapper during use. This can reduce the passage of combustion gases around the combustible heat source.

The intumescent layer may be in contact with the combustible heat source indirectly via one or more intermediate components. In preferred embodiments, the intumescent layer is in direct contact with a combustible heat source. With this arrangement, the bulging layer can compensate for surface roughness or geometrical defects of the combustible heat source and can reduce the passage of combustion gases around the combustible heat source.

The swelling layer surrounds the combustible heat source.

In the context of this document, the terms "surround" and "surrounding" have their usual meaning, meaning "passing around the entire circumference". Thus, "surrounding" the combustible heat source, the swelling layer passes along the entire circumference of the combustible heat source.

This may have the advantage that the swelling layer forms a continuous ring around the combustible heat source, and thus the passage of combustion gases around the heat source can be reduced. Therefore, the retraction resistance, or "RTD", of an aerosol generating article can be maintained. If the combustible heat source is a continuous combustible heat source and the aerosol-generating article includes one or more air inlets through which air can be drawn into the aerosol-generating substrate, this arrangement allows the aerosol-generating substrate to enter, during use, substantially all of the air flow through the air inlets for the desired aerosol properties.

The intumescent inorganic adhesive may have any suitable coefficient of expansion. For example, the intumescent inorganic adhesive may have an expansion ratio of at least about 1.5:1, preferably from about 2:1 to about 5:1, more preferably about 3:1, when heated from 20 degrees Celsius to 700 degrees Celsius. at atmospheric pressure.

The blister layer may be of any suitable thickness. In some preferred embodiments, the blister layer has a thickness of at least about 0.01 mm to about 0.1 mm, preferably from about 0.01 mm to about 0.04 mm, more preferably has a minimum thickness of about 0.02 mm. Such thicknesses have been found to be particularly effective in some instances. For example, a minimum thickness of approximately 0.02 mm will be sufficient in many instances to compensate for geometrical defects in the combustible heat source up to 0.05 mm. If the combustible heat source contains one or more dimples, the thickness can be measured in the region of the heat source that does not contain the dimples. In some cases, the thickness of the blister layer may change during the layering process during manufacture and for a multi-segment aerosol generating component or article. For example, the thickness of the layer applied during manufacture may be chosen such that the thickness of the balloon layer in the multi-segment component or aerosol generating article is at least about 0.01 mm, such as less than 0.1 mm.

The puffable inorganic adhesive may be a puffable puffable inorganic adhesive.

The inflatable inorganic adhesive may be of any suitable composition. In some preferred embodiments, the inflatable inorganic adhesive of the multi-segment aerosol generating component or article contains at least 1% by weight of water, preferably from about 1% to about 7% by weight of water, more preferably from about 1% to about 5% by weight. the weight of the water. Evaporation of water in the inorganic adhesive intumescent when heated while the combustible heat source is burning can cause bubbles to form, thus expanding or foaming the inorganic inorganic adhesive intumescent. It will be understood that such intumescent inorganic adhesives may have a higher water content when supplied for the manufacture of a multi-segment component and when applied during the manufacture of a multi-segment component or aerosol generating article. The water content of the intumescent inorganic adhesive may decrease as the intumescent inorganic adhesive dries after application during manufacture. For example, the inflatable inorganic adhesive may contain 60% by weight of water during initial delivery, but may therefore contain 30% by weight of water or less after application and drying or partial drying of the intumescent inorganic adhesive.

Preferably the swelling layer is formed from a sodium silicate adhesive.

In some embodiments, the blister layer is formed from a soda silicate adhesive having a molar ratio of about 2 to about 3.5 parts SiO ₂ to 1 part Na ₂ O.

The inflatable inorganic adhesive can be applied directly to the outer surface of the combustible heat source. In such examples, the outer surface of the combustible heat source may be substantially continuous. In some preferred embodiments, the combustible heat source has at least one shaped recess on its outer surface, and wherein the shaped recess is at least partially filled with intumescent inorganic adhesive of the intumescent layer.

With this arrangement, the retention of the combustible heat source within the wrapper can be further improved. This may help to ensure the correct position of the combustible heat source and thus the desired properties of the aerosol.

In some embodiments, at least one shaped recess is at least one longitudinal groove. This arrangement can be particularly effective because the groove is aligned parallel to the direction along which undesirable movement of the combustible heat source may occur, and thus increases the holding force applied by the inflatable inorganic adhesive to the combustible heat source in the longitudinal direction.

In some embodiments, at least one longitudinal groove comprises a plurality of circumferentially spaced longitudinal grooves.

In some embodiments, the depth of at least one shaped recess is less than about 10 percent of the outer diameter of the combustible heat source. This has the advantage that the presence of the recess does not substantially affect the mass of the heat source and hence its heating characteristics. Additionally, the time required for drying of the intumescent inorganic adhesive after it has been applied can be reduced, which improves the manufacturability.

In some examples, the depth of at least one shaped recess is from about 0.05 mm to about 0.8 mm, for example, from about 0.2 mm to 0.4 mm.

In some embodiments, the implementation of the depth of at least one shaped recess decreases towards its downstream end. This has the advantage that the retention of the heat source can be further improved as the bulging inorganic adhesive can act as a wedge to resist the upstream movement of the heat source relative to the wrap. It has also been found that this results in improved filling of at least one recess with the intumescent inorganic adhesive, since the intumescent inorganic adhesive flows more easily along the length of the recess during manufacture.

In such examples, the depth of at least one shaped recess may decrease gradually along the transition portion or in steps.

In some embodiments, the combustible heat source comprises a tail having a substantially constant cross section, with at least one recess terminating at the upstream end of the tail. With this arrangement, at least one recess does not extend into the rear, and therefore the rear forms a baffle to reduce the passage of combustion gases around the heat source in the downstream direction. The rear portion may define the maximum outside diameter of the combustible heat source. Such an arrangement can improve ease of manufacture by making it easier to wrap the wrap around a heat source. It can also improve conductive heat transfer from the heat source to the wrap. This may be particularly advantageous in multi-segment component examples where the wrapper comprises a thermal transfer layer for transferring thermal energy from the combustible heat source to the aerosol forming substrate.

The rear portion of the combustible heat source may be of any suitable size. In some preferred embodiments, the posterior has a length of less than about 3 mm, preferably from about 2 mm to about 3 mm.

In some preferred embodiments, the radially outer edges of at least one shaped recess are curved with a radius of curvature of at least about 0.05 mm. This can advantageously lead to improved filling of the recess with adhesive. This may also result in reduced visibility of the at least one recess through the wrapper and reduced risk of damage to the wrapper caused by the radially outer edges of the at least one recess during wrapping. In addition, with this arrangement, the radially outer edges of the combustible heat source are less likely to be damaged or destroyed during manufacture, which reduces the amount of dust, such as carbon dust, generated during manufacture. Preferably, the radius of curvature is from about 0.05 mm to about 0.5 mm, more preferably from about 0.2 mm to about 0.4 mm.

In some examples, the number of shaped recesses may be from 8 to 17, preferably from 12 to 16. In some examples of the invention, the shaped recesses are substantially evenly spaced around the periphery of the combustible heat source.

The outer diameter of the combustible heat source may vary along its length. In some embodiments, the outside diameter of the combustible heat source is substantially constant along substantially the entire length of the combustible heat source. This can lead to improved manufacturing manufacturability.

The multi-segment component includes a wrapper surrounding the combustible heat source along at least a portion of its length. A wrapper can be formed from one or more elements. For example, the wrapper may be formed from a single sheet of material.

In some embodiments, the wrapper comprises one or more layers of thermally conductive material. Preferably, one or more layers of thermally conductive material are located around at least the rear of the combustible heat source and at least the front of the aerosol generating substrate. In such embodiments, the thermally conductive material provides thermal communication between the combustible heat source and the aerosol generating substrate and advantageously facilitates sufficient heat transfer from the combustible heat source to the aerosol generating substrate to form an acceptable aerosol. The thermally conductive material may be in direct contact with one or both of the following: a combustible heat source and an aerosol generating substrate. Alternatively or additionally, the thermally conductive material layer may be spaced apart from one or both of the combustible heat source and the aerosol generating substrate such that there is no direct contact between the thermally conductive material and one or both of the combustible heat source and the aerosol generating substrate. .

One or more layers of thermally conductive material are preferably non-combustible. In some embodiments, one or more layers of thermally conductive material may restrict the supply of oxygen. In other words, one or more layers of thermally conductive material can weaken or prevent the passage of oxygen through the wrap.

Suitable thermal materials for use in the multi-segment components of the invention include, but are not limited to: metal foil wraps such as, for example, aluminum foil wraps, steel wraps, iron foil wraps, and copper foil wraps; and metal alloy foil wrappers.

In some embodiments, the implementation of the wrap contains one or more layers of thermal insulation material. With this arrangement, the thermal barrier material reduces heat transfer from the combustible heat source to the outer surface of the wrapper, reducing the surface temperature of the aerosol generating article. Preferably, the thermal insulation material is non-combustible. The addition of a non-combustible heat insulating layer advantageously helps to reduce the ignition propensity of aerosol generating articles containing the multi-segment components of the invention by lowering the surface temperature of the aerosol generating article.

The wrapper may be a layered wrapper formed from multiple layers.

The wrapper may comprise a radially outer layer of thermally conductive material and a radially inner layer of thermally insulating material. In some embodiments, the wrapper comprises a radially inner layer of thermally conductive material and a radially outer layer of thermally insulating material. Other arrangements are possible. In preferred arrangements, the wrapper can advantageously conduct heat from the combustible heat source to the aerosol forming substrate while controlling radiative heat loss from the combustible heat source and the combustible heat source.

In the context of this document, the term "bulging layer" means a layer that expands under the influence of elevated temperatures, not only due to its coefficient of thermal expansion.

In the context of this document, the term "inorganic adhesive" refers to an adhesive or combination of adhesives that are substantially free of carbon.

In the context of this document, the term "expansion ratio" refers to the ratio of the thickness of the intumescent layer before expansion to the thickness of the intumescent layer after expansion.

In the context of this document, the phrase "bulging layer has a thickness component" refers to the size of the layer in the radial direction.

In the context of this document, the term "longitudinal" is used to describe the direction between the proximal end and the opposite distal end of a smoking article.

In the context of this document, the terms "radial" and "transverse" are used to describe a direction perpendicular to the direction between the proximal end and the opposite distal end of a smoking article.

In the context of this document, the term "length" is used to describe the maximum dimension in the longitudinal direction of a smoking article. That is, the maximum dimension in the direction between the proximal end and the opposite distal end of the smoking article in the direction between the proximal end and the opposite distal end of the smoking article.

In the context of this document, the term "thickness" refers to the maximum size of the bulging layer in the radial direction.

In the context of this document, the term "groove" refers to an elongated depression in the surface of the heat source.

In the context of this document, the term "shaped recess" refers to a recess with predetermined dimensions, which is specially formed in the outer surface of a combustible heat source.

In the context of this document, the term "diameter" means the maximum transverse dimension of the elongated combustible heat sources according to the invention.

As used herein, the phrase "the depth of at least one recess decreases towards its downstream end" means that the depth of each recess at a first location along its length is greater than the depth of each recess at a second location that is downstream of the first locations. This applies to embodiments in which the depth of each recess is greatest at or near its upstream end, as well as embodiments in which the depth of each recess is greatest at a point between its upstream and downstream ends. ends.

As used herein, the phrase "the outer diameter of the combustible heat source is substantially constant" means that the outer boundary of the heat source, i.e., the smallest space within which the heat source can be placed, remains substantially the same along the length of the heat source.

In the context of this document, the term "thermal insulation material" is used to describe a material having a bulk thermal conductivity of less than about 50 milliwatts per meter-kelvin (mW/(m⋅K)) at 23°C and 50% relative humidity, as measured using the method modified non-stationary flat source (MTPS).

In the context of this document, the term "thermal conductive material" is used to describe a material having a bulk thermal conductivity of at least about 10 watts per meter kelvin (W/(m⋅K)) at 23°C and 50% relative humidity, as measured with using the modified non-stationary flat source (MTPS) method.

In the context of this document, the term "aerosol-forming substrate" is used to describe a substrate that is capable of releasing volatile compounds when heated, which can form an aerosol.

The aerosols generated by the aerosol-forming substrates of the multi-segment components of the invention may be visible or invisible and may contain vapors (e.g., fine particles of substances that are in a gaseous state and are usually liquid or solid at room temperature), as well as gases and droplets condensed vapor liquids.

In the context of this document, the term "non-combustible" is used to describe a material that is essentially non-combustible at the temperatures reached by a combustible heat source during its combustion and ignition.

As used herein, the term "flammability" refers to the ability of aerosol generating articles, such as smoking articles, to cause combustion of the substrate on which they are placed. The ignition propensity must be low enough to eliminate, reduce or almost completely eliminate the possibility of the aerosol generating article igniting the substrate on which it is placed. The ignition propensity can be measured according to ISO 12863:2010(E).

The combustible heat source is preferably a solid heat source and may comprise any suitable combustible material, including, but not limited to, carbon-based materials and carbon-based materials containing aluminum, magnesium, one or more carbides, one or more nitrides, and combinations thereof. Solid combustible heat sources for heated smoking articles and methods for producing such heat sources are known in the art and are described, for example, in US 5,040,552 A and US 5,595,577 A. Typically, known solid combustible heat sources for heated smoking articles are based on carbon. , that is, they contain carbon as the main combustible material.

The combustible heat source is preferably a continuous combustible heat source. In the context of this document, the term "solid" describes a heat source that does not contain any channels for air flow extending from the front end surface to the rear end surface of the combustible heat source. In the context of this document, the term "solid" is also used to describe a combustible heat source containing one or more airflow channels extending from the front end surface of the combustible heat source to the rear end surface of the combustible heat source, and a combustible, essentially airtight partition between the rear the end surface of the combustible heat source and the aerosol-forming substrate prevents air from being drawn along the length of the combustible heat source through the one or more air flow channels.

Multi-segment components according to the invention, containing solid combustible heat sources, contain one or more air inlets located downstream of the rear end surface of the combustible heat source, for the purpose of drawing air into the interior of one or more air flow passages. Multi-segment components according to the invention containing non-continuous combustible heat sources may also include one or more air inlets located downstream of the rear end surface of the combustible heat source for the purpose of drawing air into the interior of one or more air flow passages.

In certain preferred embodiments, multi-segment components of the invention comprising continuous combustible heat sources comprise one or more air inlets located near the downstream end of the aerosol generating substrate.

In use, air drawn in for inhalation by a user through one or more airflow passages of aerosol generating articles comprising multi-segment components of the invention comprising a continuous combustible heat source does not pass through any airflow passages along the continuous combustible heat source. The absence of any airflow passages through the continuous combustible heat source advantageously substantially prevents or suppresses the activation of combustion of the continuous combustible heat source during a user puff. This essentially prevents or suppresses peaks in the temperature of the aerosol-forming substrate during a puff performed by the user.

By preventing or suppressing the activation of combustion of the continuous combustible heat source, and thus preventing or suppressing excessive temperature rises in the aerosol-generating substrate, combustion or pyrolysis of the aerosol-generating substrate can advantageously be prevented in heavy puffing modes. Additionally, the effect of the user's puff mode on the composition of the main aerosol spray can advantageously be minimized or reduced.

The addition of a continuous combustible heat source can also advantageously substantially prevent or suppress combustion and decomposition products and other materials generated by the ignition and combustion of a continuous combustible heat source into the air drawn through the multi-segment components according to the invention when they are used. This is particularly advantageous if the continuous combustible heat source contains one or more additives to promote ignition or combustion of the continuous combustible heat source.

In the multi-segment components of the invention comprising a continuous combustible heat source, heat transfer from the continuous combustible heat source to the aerosol-forming substrate occurs primarily by conduction, and heating of the aerosol-forming substrate by forced convection is minimized or reduced. This may advantageously help to minimize or reduce the influence of the user's puffing pattern on the composition of the mainstream aerosol of the smoking articles of the invention.

In multi-segment components according to the invention containing a continuous combustible heat source, it is especially important to optimize the conductive heat transfer between the combustible heat source and the aerosol generating substrate. As further described below, the addition of one or more thermal conductive elements around at least the rear of the combustible carbonaceous heat source and at least the front of the aerosol generating substrate is particularly preferred in inventive multi-segment components that comprise continuous heat sources, with heating aerosol-forming substrate due to forced convection is negligible or completely absent.

It should be understood that the multi-segment components of the invention may comprise continuous combustible heat sources containing one or more closed or blocked passages through which air cannot be drawn in by the user for inhalation.

For example, the multi-segment components of the invention may comprise continuous combustible heat sources comprising one or more closed bores extending from the front end surface at the upstream end of the continuous combustible carbonaceous heat source only along a portion of the length of the continuous combustible carbonaceous heat source.

The addition of one or more closed air passages increases the surface area of the continuous combustible heat source exposed to oxygen from the air and can advantageously promote ignition and continuous combustion of the continuous combustible heat source.

In some embodiments, the combustible heat source includes at least one longitudinal air flow passage providing one or more air flow passages through the heat source. As used herein, the term "airflow duct" is used to describe a duct running along the length of the heat source through which air can be drawn through the smoking article for inhalation by the user. Such heat sources containing one or more longitudinal airflow channels are referred to herein as "discontinuous" heat sources.

The diameter of the at least one longitudinal airflow passage may be from about 1.5 mm to about 3 mm, more preferably from about 2 mm to about 2.5 mm. The inner surface of at least one longitudinal airflow channel may be partially or completely covered, as described in more detail in document WO 2009/022232 A.

The aerosol-forming substrate may be a solid aerosol-forming substrate. Alternatively, the aerosol forming substrate may contain both solid and liquid components. The aerosol-forming substrate may comprise a tobacco-containing material containing volatile tobacco flavor compounds that are released from the substrate upon heating. Alternatively, the aerosol forming substrate may comprise non-tobacco material. The aerosol-forming substrate may further comprise one or more aerosol-forming agents. Examples of suitable aerosol forming agents include, but are not limited to, glycerin and propylene glycol.

In some embodiments, the aerosol generating substrate is a rod containing tobacco-containing material.

If the aerosol-forming substrate is a solid aerosol-forming substrate, then the solid aerosol-forming substrate may comprise, for example, one or more of the following: powder, granules, pellets, grains, thin tubes, strips, or sheets containing one or a few of the following: grass leaves, tobacco leaves, tobacco stem fragments, reconstituted tobacco, homogenized tobacco, extruded tobacco, and exploded tobacco. The aerosol-forming solid substrate may be in loose form or may be provided in a suitable container or cartridge. For example, the aerosol-forming material of the solid aerosol-forming substrate may be placed in a paper or other wrapper and be in the form of a plug. If the aerosol-forming substrate is in the form of a plug, then the entire plug, including any wrapper, may be considered an aerosol-forming substrate.

Optionally, the solid aerosol-forming substrate may contain additional tobacco or non-tobacco volatile aroma compounds designed to release the solid aerosol-forming substrate upon heating. The solid aerosol-forming substrate may also contain capsules which contain, for example, additional tobacco or non-tobacco volatile aroma compounds, and such capsules may melt during heating of the solid aerosol-forming substrate.

Optionally, the aerosol-forming solid substrate may be provided on or embedded in a thermostable support. The carrier may be in the form of a powder, granules, beads, grains, thin tubes, strips or sheets. The solid aerosol-forming substrate may be applied to the surface of the carrier in the form of, for example, a sheet, foam, gel, or suspension. The solid aerosol-forming substrate may be applied to the entire surface of the wearer, or alternatively may be applied in a pattern to provide non-uniform flavor delivery during use.

The aerosol forming substrate may be in the form of a plug or segment containing a material capable of releasing volatile compounds when heated, surrounded by a paper or other wrapper. As stated above, where the aerosol-forming substrate is in the form of such a plug or segment, the entire plug or segment, including any wrapper, is considered to be an aerosol-forming substrate.

The aerosol generating substrate preferably has a length of from about 5 mm to about 20 mm. In some embodiments, the aerosol generating substrate may be about 6 mm to about 15 mm long, or about 7 mm to about 12 mm long.

In preferred embodiments, the aerosol forming substrate comprises a tobacco-based material wrapped in a ficelle. In particularly preferred embodiments, the aerosol forming substrate comprises a strand of homogenized tobacco-based material wrapped in a ficelle.

In any of the embodiments described above, the combustible heat source and the aerosol-forming substrate may abut each other in coaxial alignment. Advantageously, the intumescent layer can, during use, keep the combustible heat source in direct contact with the aerosol-forming substrate, providing good thermal communication between the two components and maintaining the temperature of the aerosol-forming substrate within a desired range.

In the context of this document, the terms "butt" and "butt" are used to describe a component or part of a component that is in direct contact with another component or part of a component.

The multi-segmented components of the invention may comprise a heat transfer element positioned around and in direct contact with both at least the rear of the combustible heat source and at least the front of the aerosol generating substrate. In such embodiments, the heat transfer element provides thermal communication between the combustible heat source and the aerosol generating substrate of the smoking articles of the invention and advantageously facilitates sufficient heat transfer from the combustible heat source to the aerosol generating substrate to form an acceptable aerosol.

Alternatively or additionally, the multi-segmented components of the invention may comprise a heat transfer element spaced apart from one or both of the following: a combustible heat source and an aerosol generating substrate such that there is no direct contact between the heat transfer element and one or both of the following: a combustible heat source and aerosol-forming substrate.

In the case where the multi-segment component comprises a heat transfer element disposed around at least the rear of the combustible heat source and at least the front of the aerosol forming substrate, the heat transfer element may be formed by a wrap. For example, the wrapper may include one or more layers of thermally conductive material that form one or more thermally conductive elements.

One or more heat-conducting elements are preferably non-combustible. In some embodiments, one or more heat transfer elements may restrict the supply of oxygen. In other words, one or more heat transfer elements can weaken or prevent the passage of oxygen through the heat transfer element.

Suitable heat transfer elements for use in the multi-segment components of the invention include, but are not limited to: metal foil wraps such as, for example, aluminum foil wraps, steel wraps, iron foil wraps, and copper foil wraps; and metal alloy foil wrappers.

The multi-segment components of the invention may further comprise a lid configured to at least partially cover the front end surface of the combustible heat source, the lid being removable to expose the front end surface of the combustible heat source prior to use of the smoking article.

In the context of this document, the term "cover" refers to a protective coating that essentially surrounds the distal end of a multi-segment component, including the front end surface. Providing a lid that is removed prior to ignition of the combustible heat source advantageously protects the combustible heat source prior to use.

For example, the multi-segment components of the invention may comprise a removable cap attached at the line of least resistance to the distal end of the smoking article, the cap comprising a cylindrical rod of material surrounded by a wrapper as described in WO 2014/086998 A1.

The multi-segment components of the present invention may further comprise a transfer element or separation element located downstream of the aerosol generating substrate. Such an element may be in the form of a hollow tube located downstream of the aerosol generating substrate.

The moving element may abut against the aerosol generating substrate. Alternatively, the transfer element may be positioned at a distance from the aerosol generating substrate. The displacement element may be in coaxial alignment with one or both of the following: a combustible heat source and an aerosol generating substrate.

The addition of the transfer element advantageously allows the aerosol generated by heat transfer from the combustible heat source to the aerosol-forming substrate to be cooled. The addition of the transfer element also advantageously allows the overall length of the aerosol generating article containing the multi-segment component according to the invention to be adjusted to a desired value, for example to a length similar to the length of a conventional cigarette, by appropriate selection of the length of the transfer element.

The transfer element may be from about 7 mm to about 50 mm in length, such as from about 10 mm to about 45 mm, or from about 15 mm to about 30 mm. The transfer element may have other lengths depending on the desired overall length of the aerosol generating article and the presence and length of other components in the multi-segment component or the aerosol generating article containing the multi-segment component.

Preferably, the moving element comprises at least one tubular hollow body with an open end. In such embodiments, in use, air drawn into the aerosol generating article passes through at least one open-ended tubular hollow body as it passes downstream through the aerosol generating article.

The displacement element may comprise at least one open-ended tubular hollow body made of one or more suitable materials that are substantially thermally stable at the temperature of the aerosol generated by transferring heat from a combustible heat source to the aerosol-forming substrate. Suitable materials are known in the art and include, but are not limited to, paper, cardboard, plastics such as cellulose acetate, ceramics, and combinations thereof.

Alternatively or additionally, the multi-segment components of the invention may comprise an aerosol cooling element or heat exchanger downstream of the aerosol generating substrate. The aerosol cooling element may comprise several channels extending in the longitudinal direction.

The cooling spray element may comprise an assembled sheet of material selected from the group consisting of metal foil, polymeric material, and substantially non-porous paper or paperboard. In some embodiments, the cooling aerosol element may comprise an assembled sheet of material selected from the group consisting of polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyethylene terephthalate (PET), polylactic acid (PLA), cellulose acetate (CA ) and aluminum foil.

In some preferred embodiments, the cooling aerosol element may comprise an assembled sheet of biodegradable polymeric material such as polylactic acid (PLA) or Mater- ^Bi® brand (a commercially available starch-based copolyester series).

The multi-segment components of the invention comprise a wrapper that surrounds the combustible heat source along at least a portion of its length. Preferably, the wrap surrounds at least the front of the aerosol forming substrate and at least the back of the combustible heat source. In preferred embodiments, the wrapper surrounds the aerosol generating substrate, at least the back of the combustible heat source, and any other components of the smoking article downstream of the aerosol generating substrate.

The wrapper may be formed from any suitable material or combination of materials. Suitable materials are well known in the art and include, but are not limited to, cigarette paper.

According to a second aspect of the invention, an aerosol generating article is provided, comprising a multi-segment component according to any of the embodiments described above.

The aerosol generating article may be a smoking article.

The combustible heat source is located at or near the distal end of the aerosol generating article. The mouth end of the aerosol generating article is located downstream of the distal end of the aerosol generating article. The proximal end of the aerosol generating article may also be referred to as the downstream end of the aerosol generating article, and the distal end of the aerosol generating article may also be referred to as the upstream end of the aerosol generating article. Components or parts of the components of the aerosol generating article and the multi-segment component can be described as upstream or downstream of each other based on their relative positions between the proximal end of the aerosol generating article and the distal end of the aerosol generating article. The mouth end is located downstream of the distal end.

In the context of this document, the terms "upstream" and "front" and "downstream" and "rear" are used to describe the relative positions of the components or parts of the components of a multi-segment component relative to the direction in which the user puffs on an aerosol generating article containing multi-segment component, at the time of its use. The aerosol generating articles of the invention comprise a proximal end through which, in use, the aerosol exits the aerosol generating article for delivery to a user. The proximal end of the aerosol generating article may also be referred to as the mouth end. In use, the user puffs on the mouth end of the aerosol generating article to inhale the aerosol generated by the aerosol generating article.

The aerosol generating articles according to the invention preferably comprise a mouthpiece located at their proximal end.

Preferably the mouthpiece has a low filtration efficiency, more preferably a very low filtration efficiency. The mouthpiece may be a one-segment or one-piece mouthpiece. Alternatively, the mouthpiece may be a multi-segment or multi-piece mouthpiece.

The mouthpiece may contain a filter containing one or more segments containing suitable known filter materials. Suitable filter materials are known in the art and include, but are not limited to, cellulose acetate and paper. Alternatively or additionally, the mouthpiece may contain one or more segments containing absorbents, adsorbents, flavors and other aerosol modifiers and additives, or combinations thereof.

The aerosol generating articles of the invention may comprise a multi-segment component according to any of the embodiments described above and a mouthpiece segment at the downstream end of the multi-segment component.

Alternatively, the aerosol generating articles of the invention may comprise a first multi-segment component according to any of the embodiments described above and a second multi-segment component located downstream of the first multi-segment component, the second multi-segment component having a mouthpiece located at its proximal end. The second multi-segment component may include an element that cools the aerosol, located upstream of the mouthpiece. The second multi-segment component may include a moving element or a spacer element located upstream of the mouthpiece. In some embodiments, the implementation of the second multi-segment component contains an element that cools the aerosol, and a moving element or a separating element located upstream of the mouthpiece.

In one particular embodiment, the aerosol generating article comprises a first multi-segment component comprising a combustible heat source, an aerosol generating substrate located downstream of the combustible heat source, and a transfer element or separation element located downstream of the aerosol generating substrate. , and a second multi-segment component at the downstream end of the first multi-segment component, wherein the second multi-segment component comprises an aerosol cooling element, a moving element or a spacer element located downstream of the aerosol cooling element, and a mouthpiece at its proximal end.

The aerosol generating articles of the present invention may have a substantially cylindrical shape. The aerosol generating article may be substantially elongated. The aerosol generating article has a length and a circumference substantially perpendicular to the length.

The aerosol forming substrate may be substantially cylindrical in shape. The aerosol forming substrate may be substantially elongated. The aerosol forming substrate also has a length and a circumference substantially perpendicular to the length. The aerosol-generating substrate may be positioned in the aerosol-generating article such that the length of the aerosol-generating substrate is substantially parallel to the direction of air flow in the aerosol-generating article.

The moving part or element may be substantially elongated.

The aerosol generating articles according to the invention may be of any desired length. For example, aerosol generating articles of the invention may have an overall length of from about 65 mm to about 100 mm.

The aerosol generating articles according to the invention may have any desired outside diameter. For example, aerosol generating articles of the invention may have an outer diameter of from about 5 mm to about 12 mm.

The assembly of the aerosol generating articles according to the invention can be carried out using known methods and equipment.

In a third aspect of the invention, a method for manufacturing a multi-segment component for an aerosol generating article is provided, comprising the steps of: providing a combustible heat source; providing an aerosol-forming substrate downstream of a combustible heat source; applying a blistering inorganic adhesive to the web of wrapping material; and wrapping the web of wrap material around the combustible heat source to form a wrapper surrounding the combustible heat source along at least a portion of its length, wherein the inflatable inorganic adhesive forms an inflatable layer between the combustible heat source and the wrapper.

The step of applying the intumescent inorganic adhesive may be carried out in any suitable manner. For example, the inflatable inorganic adhesive may be applied by one or more of the following: spreading, spraying, using a glue gun or rotogravure printing, or other printing methods.

The blister layer may be of any suitable thickness. In some preferred embodiments, an inflatable inorganic adhesive is applied to a web of wrap material and the web is wrapped around a combustible heat source such that the inflatable layer has a thickness of at least about 0.01 mm to about 0.1 mm, preferably about 0.01 mm. mm to about 0.04 mm, more preferably a minimum thickness of about 0.02 mm.

The puffable inorganic adhesive may be a puffable puffable inorganic adhesive. The inflatable inorganic adhesive may be of any suitable composition. In some preferred embodiments, the inflatable inorganic adhesive may contain from about 40% to about 75% by weight of water when applied to the web of wrap material, preferably from about 50% to about 65% by weight of water when applied to the web of wrap material. The water content of the intumescent inorganic adhesive can be reduced after it has been applied to the web of wrap material. In some preferred embodiments, after the multi-segment component is formed and the inflatable inorganic adhesive has dried or partially dried, the inorganic adhesive inflatable contains at least 1% by weight of water, preferably from about 1% to about 7% by weight of water, more preferably from about 1% to approximately 5% by weight of water.

In another further aspect of the invention, a method for manufacturing an aerosol generating article is provided, comprising the steps of providing a multi-segment component manufactured in accordance with any of the methods described above and providing a mouthpiece downstream of the multi-segment component. Preferably the mouthpiece has a low filtration efficiency, more preferably a very low filtration efficiency. The mouthpiece may be a one-segment or one-piece mouthpiece. Alternatively, the mouthpiece may be a multi-segment or multi-piece mouthpiece. The mouthpiece may contain a filter containing one or more segments containing suitable known filter materials. Suitable filter materials are known in the art and include, but are not limited to, cellulose acetate and paper. Alternatively or additionally, the mouthpiece may contain one or more segments containing absorbents, adsorbents, flavors and other aerosol modifiers and additives, or combinations thereof.

The mouthpiece may be located at the downstream end of the multi-segment component. Alternatively, the step of providing a mouthpiece may be performed by providing a second multi-segment component downstream of the first multi-segment component, the second multi-segment component having a mouthpiece disposed at its proximal end. The second multi-segment component may include an aerosol cooling element located upstream of the mouthpiece. The second multi-segment component may include a moving element or a spacer element located upstream of the mouthpiece. In some embodiments, the implementation of the second multi-segment component contains an element that cools the aerosol, and a moving element or a separating element located upstream of the mouthpiece. In one particular embodiment, the aerosol generating article comprises a first multi-segment component comprising a combustible heat source, an aerosol generating substrate located downstream of the combustible heat source, and a transfer element or separation element located downstream of the aerosol generating substrate. , and a second multi-segment component at the downstream end of the first multi-segment component, wherein the second multi-segment component comprises an aerosol cooling element, a moving element or a spacer element located downstream of the aerosol cooling element, and a mouthpiece at its proximal end.

All scientific and technical terms used in this document have the meanings commonly used in the art, unless otherwise indicated. The definitions provided in this document are intended to facilitate understanding of certain terms commonly used in this document.

Features described in relation to one or more aspects may equally apply to other aspects of the invention. In particular, the features described with respect to the multi-segment component according to the first aspect can be equally applied to the aerosol generating article according to the second aspect, and vice versa. Additionally, the features described with respect to the multi-segment component according to the first aspect or the aerosol generating article according to the second aspect can equally be applied to the manufacturing method according to the third aspect.

The invention will be further described solely by way of examples with reference to the accompanying drawings, in which:

in fig. 1 is a schematic longitudinal sectional view of a smoking article containing a multi-segment component according to a first embodiment of the invention;

in fig. 2A is a schematic perspective view of a combustible heat source for the multi-segment component of FIG. one;

in fig. 2B is a schematic cross-sectional view of the combustible heat source of FIG. 2A; and

in fig. 3A and FIG. 3B are schematic representations of a manufacturing method for manufacturing the multi-segment component of FIG. one.

The smoking article 2 according to the first embodiment of the invention shown in FIG. 1 comprises a continuous combustible heat source 4 having a front surface 6 and an opposite rear surface 8, an aerosol forming substrate 10, a moving element 12, a cooling aerosol element 14, a spacer element 16 and a mouthpiece 18 which abut each other in coaxial alignment. .

The continuous combustible heat source 4 is a continuous carbonaceous combustible heat source and is located at the distal end of the smoking article 2. As shown in FIG. 1, a non-combustible, substantially airtight baffle 22 in the form of an aluminum foil disk is provided between the rear surface 8 of the solid combustible heat source 4 and the aerosol generating substrate 10. The baffle 22 is applied to the rear surface 8 of the solid combustible heat source 4 by pressing an aluminum foil disc onto the rear surface 8 of the solid combustible heat source 4 and rests against the rear surface 8 of the combustible carbon-containing heat source 4 and the aerosol-forming substrate 10.

In other embodiments (not shown), the non-combustible, substantially airtight partition 22 between the rear surface 8 of the solid combustible heat source 4 and the aerosol-forming substrate 10 may be omitted.

The aerosol-forming substrate 10 is located directly downstream of the baffle 22 deposited on the rear surface 8 of the continuous combustible heat source 4. The aerosolizing substrate 10 comprises a cylindrical extrusion of a homogenized tobacco-based material 24 containing an aerosolizing agent, such as, for example, glycerol, wrapped in a ficelle 26.

The transfer element 12 is located immediately downstream of the aerosol generating substrate 10 and includes a cylindrical hollow cellulose acetate tube 28 with an open end.

The cooling spray element 14 is located immediately downstream of the transfer element 12 and contains an assembled sheet of biodegradable polymeric material such as, for example, polylactic acid.

The separating element 16 is located immediately downstream of the aerosol cooling element 14 and contains a cylindrical hollow paper or cardboard tube 30 with an open end.

The mouthpiece 18 is located immediately downstream of the spacer 16. As shown in FIG. 1, the mouthpiece 18 is located at the proximal end of the smoking article 2 and contains a cylindrical plug of a suitable filter material 32, such as, for example, very low efficiency cellulose acetate, wrapped in a filter ficell 34.

As shown in FIG. 1, the smoking article 2 further comprises a single heat transfer element 36 of a suitable material, such as, for example, aluminum foil, overlying the back of the solid combustible heat source 4, the entire length of the aerosol generating substrate 10, and the entire length of the transfer element 12.

In other embodiments of the invention (not shown), the displacement element 12 may extend beyond the single thermal element 36 in a downstream direction. That is, the single thermal element 36 may lie on top of only the front of the displacement element 12. In other embodiments of the invention (not shown), the single thermal element 36 may not lie on top of any portion of the displacement element 12.

In additional embodiments of the invention (not shown), the aerosol-forming substrate 10 may extend beyond the single thermally conductive element 36 in a downstream direction. That is, the single heat transfer element 36 may lie on top of only the front portion of the aerosol forming substrate 10.

The single heat transfer element 36 is surrounded by a wrapper 38 of a sheet of heat insulating material, such as, for example, low air permeability cigarette paper, which is wrapped around the aerosol forming substrate 10, the transfer element 12, and the back of the continuous combustible heat source 4 to form a multi-segment smoking component 50 products 2.

The element 14, the cooling spray, the separation element 16, and the mouthpiece 18 may be surrounded by an additional wrapper (not shown) to form a second multi-segment component (also not shown) downstream of the multi-segment component 50. In such examples, the multi-segment component 50 and the second multi-segment component may be held together by an outer wrap 20 or an additional wrap, or a band of tipping paper. Alternatively, element 14, cooling mist, separation element 16, and mouthpiece 18 may be separate segments that are held together and connected to multi-segment component 50 via outer wrap 20.

In other embodiments (not shown), the wrapper 38 may extend downstream of the transfer element 12, surrounding other components of the smoking article 2, such as the cooling spray element and the separation element 16, which are then included in the multi-segment component. The mouthpiece 18 may then be attached at the downstream end of the multi-segment component with an overwrap 20 or an additional wrapper or tipping paper strip (not shown).

In the smoking article 2 according to the first embodiment of the invention shown in FIG. 1, the single thermal element 36 and the wrap 38 extend to approximately the same position on the solid combustible heat source 4 in the upstream and downstream directions, thus the upstream ends of the single thermal element 36 and the wrap 38 are substantially aligned. over the solid combustible heat source 4, and thus the downstream ends of the single heat transfer element 36 and wrap 38 are substantially aligned with the downstream end of the displacement element 12.

However, it should be understood that in other embodiments of the invention (not shown), the wrapper 38 may extend beyond the single thermal element 36 in an upstream direction.

The smoking article 2 according to the first embodiment of the invention comprises one or more first air inlets 38 around the periphery of the aerosol-forming substrate 10.

As shown in FIG. 1, a circumferential arrangement of the first air inlets 40 is provided in the ficell 26 of the aerosol-forming substrate 10, the wrapper 38, and the single thermal conductive member 36 in order to allow cold air (shown by dashed arrows in FIG. 1) to pass into the aerosol-forming substrate 10. spray can.

Also in FIG. 1 shows an intumescent layer 42 positioned between a combustible heat source 4 and a wrap 38. In this example, an intumescent layer 42 is located on the inner surface of the heat transfer element 36 such that it is in direct contact with the combustible heat source 4. In other examples (not shown), the intumescent layer 42 may be in contact with the combustible heat source 4 indirectly, for example, through the heat-conducting element 36. The intumescent layer 42 surrounds the combustible heat source 4 and is configured to expand in response to heat from the combustible heat source 4 . The intumescent layer 42 is formed from an inorganic intumescent adhesive. Suitable intumescent inorganic adhesives include sodium silicate adhesives, for example, from PQ Corporation, Malvern, PA, USA.

As described below with respect to FIG. 2A and FIG. 2B, the combustible heat source may comprise one or more shaped recesses on its outer surface that are filled or partially filled with the intumescent inorganic adhesive of the intumescent layer 42 to improve retention of the combustible heat source 4 within the wrapper 38.

The smoking article may further comprise a band of tipping paper (not shown) surrounding the downstream end portion of the outer wrapper 20.

The multi-segment component 50 may further comprise a removable cover (not shown) at its distal end which is directly adjacent to the heat source 4. For example, the release lid may comprise a core containing a desiccant, such as glycerin, to absorb moisture, compared to a heat source that is wrapped by part of one or both of the following: outer wrap 20 and wrap 38, and connected to the rest of said wrap at a line of least resistance containing a plurality of perforations in the wrapper that surrounds the smoking article 2. In such examples, to use the smoking article, the user removes the removable cover by laterally squeezing the cover by pinching it between thumb and forefinger. When the lid is compressed, sufficient force is applied to the line of least resistance to locally break the wrapper by which the lid is attached. The user then removes the lid by twisting the lid to break the remainder of the line of least resistance. Upon removal of the cap, the heat source is partially open, allowing the user to light the smoking article.

In use, the user ignites the solid combustible heat source 4 of the smoking article 2 according to the first embodiment of the invention and then puffs through the mouthpiece 18. When the user puffs through the mouthpiece 18, air (shown by dotted arrows in FIG. 1) is drawn into the aerosol-forming substrate 10 , smoking article 2 through the air inlets 40.

The front part of the aerosol-forming substrate 10 is heated by heat transfer through the back surface 8 of the continuous combustible heat source 4 and the baffle 22.

Heating the aerosol-forming substrate 10 by conduction results in the release of glycerol and other volatile and semi-volatile compounds from the extrusion of the homogenized tobacco-based material 24. The compounds emitted by the aerosol-forming substrate 10 form an aerosol, entrained by air drawn into the aerosol-forming substrate 10 of the smoking article 2 through the first air inlets 40 as it flows through the aerosol-forming substrate 10. The drawn in air and the entrained aerosol (shown by dashed arrows in FIGS. 1 and 2) pass downstream through the transfer element 12, the cooling aerosol element 14 and the separation element 16 where they are cooled and condensed. The cooled drawn air and entrained aerosol pass downstream through the mouthpiece 18 and are delivered to the user through the proximal end of the smoking article 2 according to the first embodiment of the invention. A non-combustible, substantially air-tight baffle 22 on the rear surface 8 of the solid combustible heat source 4 isolates the solid combustible heat source 4 from the air drawn in through the smoking article 2 so that, in use, the air drawn in through the smoking article 2 does not come into direct contact. with a continuous combustible heat source 4.

In use, the single heat transfer element 36 retains heat within the smoking article 2, helping to maintain the temperature of the aerosol generating substrate 10 and thus facilitating continuous and improved delivery of the aerosol. In addition, the single heat transfer element 36 transfers heat along the aerosol-forming substrate 10 so that heat is dissipated through a larger volume of the aerosol-forming substrate 10. This helps to ensure a more uniform delivery of the aerosol from puff to puff.

During heating of the intumescent layer 42 by the combustible heat source 4, the water in the intumescent inorganic adhesive evaporates to form air bubbles, thereby expanding or foaming the adhesive. Because the intumescent layer 42 is formed from the intumescent inorganic adhesive, there is substantially no loss of material or volume from the intumescent layer 42 during combustion of the combustible heat source 4. The expanded inflatable layer 42 ensures that the combustible heat source 4 remains tightly held within the wrap 38 during use, even if one or both of the heat transfer element 36 and wrap 38 are expanded due to their own thermal expansion properties. In addition to ensuring that the combustible heat source 4 remains tightly contained within the wrapper 38, the expanded inflatable layer 42 also forms a baffle around the combustible heat source 4 to reduce or prevent leakage of combustion gases around the outside of the combustible heat source 4. In this example, the intumescent layer 42 is in direct contact with the outer surface of the combustible heat source 4 . Therefore, the expanded swelling layer 42 can compensate for surface roughness of the combustible heat source or geometrical defects of the combustible heat source 4 to reduce the transmission of combustion gases around the heat source 4. Therefore, the "RTD" of the smoking article 2 can be saved. Additionally, since the combustible heat source 4 is a continuous combustible heat source, the expanded inflatable layer 42 allows substantially all of the airflow to enter the aerosol forming substrate 10 through the air inlets 40 during use for the desired properties of the aerosol.

The blister layer 42 has an unexpanded thickness of about 0.01 mm to about 0.1 mm and has an expansion ratio of about 1.5:1 to about 5:1. Therefore, the swelling layer 42 can expand without significantly affecting the appearance of the smoking article 2.

In FIG. 2A and FIG. 2B shows a combustible heat source 200 for a multi-segment component according to the present invention. The combustible heat source 200 is substantially cylindrical and has an outer diameter shown as dimension D1 in FIG. 2A and FIG. 2B, which is substantially constant along the entire length of the combustible heat source 200. The combustible heat source 200 has a front surface 206 and an opposite rear surface 208 and several shaped recesses on its outer surface 202, made in the form of several circumferentially spaced longitudinal grooves 210. The longitudinal grooves 210 extend from the front surface 206 to the rear surface 208, but end above downstream of the rear surface 208 to define a rear portion 204 having a substantially constant, circular cross section and a substantially continuous outer surface. The longitudinal grooves 210 terminate at the upstream end of the rear portion 204. The rear portion 204 extends from the downstream end of the longitudinal grooves 210 to the rear surface 208 of the combustible heat source 200 and has a length shown by dimension H1. In this example, the back length is less than about 3 mm.

Since the grooves 210 do not extend to the rear surface 208 of the combustible heat source 200 during use, the rear portion 204 can form a baffle to reduce the passage of combustion gases around the heat source in a downstream direction. The rear portion may define the maximum outside diameter of the combustible heat source. Such an arrangement can improve ease of manufacture by making it easier to wrap the wrap around a heat source. It can also improve conductive heat transfer from the heat source to the wrap. This may be particularly advantageous in multi-segment component examples where the wrapper comprises a thermal transfer layer for transferring thermal energy from the combustible heat source to the aerosol forming substrate.

During manufacture of the multi-segment component containing the combustible heat source 200, the longitudinal grooves 210 may be filled or partially filled with adhesive to improve retention of the combustible heat source 200 within the multi-segment component wrapper. Because the grooves 210 are aligned with the longitudinal axis of the combustible heat source 200, when the heat source 200 is assembled in an aerosol generating article such as the smoking article 2 described above with respect to FIG. 1, the longitudinal grooves 210 will be parallel to the upstream direction of the aerosol generating article and thus parallel to the direction in which the combustible heat source 200 may undesirably move. With this arrangement, the holding force applied by the adhesive to the combustible heat source 200 is increased by the orientation of the longitudinal grooves 210. This can help ensure that the combustible heat source is properly positioned within the aerosol generating article during use and thus the desired aerosol properties.

In this example, the longitudinal grooves 210 are evenly spaced around the circumference of the combustible heat source 200 and are substantially the same length. In other examples (not shown), the longitudinal grooves 210 may be unevenly spaced, and one or more of the longitudinal grooves 210 may be shorter or longer than the other longitudinal grooves 210.

Each of the longitudinal grooves 210 has a bottom, or trough, 212 that is connected to the outer surface 202 of the combustible heat source 200 via the radially outer edges 214 of the groove 210. The outer edges 214 are curved with a radius of curvature that is at least about 15% of the depth D2 of the corresponding im grooves. Preferably, the radius of curvature is at least about 0.05 mm. This can advantageously result in improved filling of the grooves 210 during the manufacture of the multi-segment component. This may also result in reduced visibility of the at least one recess through the wrap of the multi-segment component and reduced risk of damage to the wrap caused by the radially outer edges of the at least one recess during wrapping. In addition, with this arrangement, the radially outer edges of the combustible heat source are less likely to be damaged or destroyed during manufacture, which reduces the amount of dust, such as carbon dust, generated during manufacture.

The longitudinal grooves 210 have a depth shown by dimension D2 in FIG. 2A and FIG. 2B, which is determined by the difference between the radius of the outer surface 202 of the combustible heat source, which is shown by the dimension R1 in FIG. 2B and the bottom radius 212 of each groove 210, which is shown by dimension R2 in FIG. 2b. In this example, the depth of the grooves 210 is less than about 10 percent of the outer diameter D1 of the combustible heat source 200. This has the advantage that the presence of the longitudinal grooves 210 does not substantially affect the mass of the heat source 200 and hence its heating characteristics. Additionally, the time required for any adhesive filling the longitudinal grooves 210 to dry after it has been applied can be reduced, which improves manufacturing processability. In some examples, the depth of the longitudinal grooves 210 is from 0.05 mm to about 0.4 mm.

In this example, the depth of each longitudinal groove 210 is substantially constant along its length. In other examples (not shown), the depth of one or more grooves decreases towards their downstream end. This has the advantage that the retention of the heat source can be further improved as the adhesive can act as a wedge to resist movement of the heat source upstream of the wrap. It has also been found that this results in improved filling of the grooves 210 with adhesive as the adhesive flows more easily over the bottom surface 212 of each groove 210.

In FIG. 3A and FIG. 3B are schematic representations of a manufacturing method for manufacturing the multi-segment component of FIG. 1. In FIG. 3A and FIG. 3B, the aerosol generating substrate 10 and the transfer element 12 are omitted for clarity.

During the manufacturing method, a heat transfer sheet 336 formed from a fire resistant heat transfer material such as aluminum is placed on a web 338 of a wrapping material such as cigarette paper. The inflatable inorganic adhesive 342 is then applied to the heat transfer sheet 336 using a roller, and the combustible heat source 304 is placed on top. Suitable intumescent inorganic adhesives include sodium silicate adhesives such as the "Crystal" range of liquid silicate liquid adhesives from PQ Corporation, Malvern, PA, USA.

As shown in FIG. 3B, the paper web 338 is then pressed against the combustible heat source 304 and wrapped in a cylindrical shape around it to form a continuous tube. During this wrapping step, the inflatable inorganic adhesive 342 is spread over the outer surface of the combustible heat source 304 to form an intumescent layer. The inflatable inorganic adhesive 342 is also forced into the longitudinal grooves 310 on the outer surface of the combustible heat source 304 structurally bonding the combustible heat source 304 to the intumescent layer. The continuous tube formed by web 338 is then cut adjacent the front end of each combustible heat source 304 to form individual multi-segment rod-shaped components.

Other ways are possible. For example, other methods may be used to apply the adhesive to the wrapper, such as spreading or spraying, using a glue gun or rotogravure printing, or other printing methods. The adhesive may be applied to a combustible heat source. The adhesive can be applied to the wrapper and a combustible heat source.

Example 1

To form the swelling layer, an inorganic sodium silicate adhesive having a silica content of 28.5% to 30.0%, a sodium oxide content of 8.5% to 9.0%, and a molar ratio of 3.3 to 3.5 is applied between a combustible heat source and a wrapper using the method described above with respect to FIG. 3A and FIG. 3b.

Example 2

To form a blister layer, an inorganic sodium silicate adhesive having a silica content of about 29.9%, a sodium oxide content of about 9.4%, and a molar ratio of about 3.3 is applied between the combustible heat source and the wrapper using the method described above with respect to FIG. . 3A and FIG. 3b.

Example 3

To form the swelling layer, an inorganic sodium silicate adhesive having a silica content of 33.1% to 34.1%, a sodium oxide content of 12.0% to 13.0%, a molar ratio of 2.6 to 2.9, and a dry solids from 45.1% to 47.1% are applied between the combustible heat source and the wrapper using the method described above with respect to FIG. 3A and FIG. 3b.

Example 4

To form the swelling layer, an inorganic sodium silicate adhesive having a silica content of 29.0% to 30.5%, a sodium oxide content of 8.5% to 9.0%, and a molar ratio of 2.0 to 2.1 is applied between a combustible heat source and a wrapper using the method described above with respect to FIG. 3A and FIG. 3b.

Example 5

To form a swelling layer, an inorganic sodium silicate adhesive having a silica content of 30% to 31%, a sodium oxide content of 11.4% to 12.4%, and a molar ratio of 2.6 to 2.7 is applied between a combustible heat source and wrapping using the method described above with respect to FIG. 3A and FIG. 3b.

The specific embodiments and examples described above illustrate but do not limit the invention. It should be understood that other embodiments of the invention are possible, and the specific embodiments and examples described herein are not exhaustive.

Claims (34)

1. A multi-segment component for an aerosol-generating article, wherein the multi-segment component contains: combustible heat source; an aerosol-forming substrate downstream of the combustible heat source; and a wrapper surrounding the combustible heat source along at least a portion of its length; wherein the multi-segment component further comprises an intumescent layer located between the combustible heat source and the wrapper, the intumescent layer being formed from an intumescent inorganic adhesive. 2. The multi-segment component of claim 1, wherein the intumescent layer surrounds the combustible heat source. 3. A multi-segment component according to claim 1 or 2, wherein the intumescent inorganic adhesive has an expansion ratio of at least 1.5:1, preferably 2:1 to 5:1, more preferably 3:1, when heated from 20 degrees Celsius to 700 degrees Celsius at atmospheric pressure. 4. Multi-segment component according to any one of paragraphs. 1, 2 and 3, wherein the bulging layer has a thickness of at least 0.01 mm to 0.1 mm, preferably 0.01 mm to 0.04 mm, more preferably 0.02 mm. 5. Multi-segment component according to any one of paragraphs. 1-4, in which the blistering inorganic adhesive is a foaming blistering inorganic adhesive. 6. Multi-segment component according to any one of paragraphs. 1-5, in which the inflatable inorganic adhesive contains at least 1% by weight of water, preferably from 1% to 7% by weight of water, more preferably from 1% to 5% by weight of water. 7. Multi-segment component according to any one of paragraphs. 1-6, in which the swelling layer is formed from sodium silicate glue. 8. The multi-segment component of claim 7 wherein the sodium silicate adhesive has a molar ratio of 2 to 3.5 parts SiO ₂ to 1 part Na ₂ O. 9. Multi-segment component according to any one of paragraphs. 1-8, wherein the combustible heat source has at least one longitudinal groove on its outer surface, wherein the longitudinal groove is at least partially filled with intumescent inorganic adhesive of the intumescent layer. 10. The multi-segment component of claim 9, wherein the combustible heat source comprises a tail having a constant cross section, with at least one groove terminating at the upstream end of the tail. 11. Multi-segment component according to claim 9 or 10, wherein the radially outer edges of at least one longitudinal groove are curved with a radius of curvature of at least 0.05 mm. 12. Multi-segment component according to any one of paragraphs. 9-11, wherein the outer diameter of the combustible heat source is constant along the entire length of the combustible heat source. 13. Multi-segment component according to any one of paragraphs. 1-12, wherein the wrapper comprises a radially inner layer of thermally conductive material and a radially outer layer of thermally insulating material. 14. A method for manufacturing a multi-segment component for an aerosol generating article, the method comprising the steps of: providing a combustible heat source; providing an aerosol-forming substrate downstream of a combustible heat source; applying a blistering inorganic adhesive to the web of wrapping material; and wrapping the web of wrap material around the combustible heat source to form a wrapper surrounding the combustible heat source along at least a portion of its length, wherein the inflatable inorganic adhesive forms an inflatable layer between the combustible heat source and the wrapper. 15. The method of manufacturing a multi-segment component according to claim 14, wherein the intumescent layer surrounds the combustible heat source. 16. A method for manufacturing a multi-segment component according to claim 14 or 15, wherein the intumescent inorganic adhesive has an expansion ratio of at least 1.5:1, preferably 2:1 to 5:1, more preferably 3:1, when heated from 20 degrees Celsius to 700 degrees Celsius at atmospheric pressure. 17. A method of manufacturing a multi-segment component according to any one of paragraphs. 14-16, wherein the bulging layer has a thickness of at least 0.01 mm to 0.1 mm, preferably 0.01 mm to 0.04 mm, more preferably 0.02 mm. 18. A method of manufacturing a multi-segment component according to any one of paragraphs. 14-17, in which the bulging inorganic adhesive is a foaming blistering inorganic adhesive. 19. A method of manufacturing a multi-segment component according to any one of paragraphs. 14-18, in which the inflatable inorganic adhesive contains at least 1% by weight of water, preferably from 1% to 7% by weight of water, more preferably from 1% to 5% by weight of water. 20. A method for manufacturing a multi-segment component according to any one of paragraphs. 14-19, in which the swelling layer is formed from sodium silicate glue. 21. The method of manufacturing a multi-segment component according to claim 20, in which the sodium silicate adhesive has a molar ratio of 2 to 3.5 parts of SiO ₂ to 1 part of Na ₂ O. 22. A method for manufacturing a multi-segment component according to any one of paragraphs. 14-21, in which the combustible heat source has at least one longitudinal groove on its outer surface, and wherein the longitudinal groove is at least partially filled with intumescent inorganic adhesive of the intumescent layer. 23. The method of manufacturing a multi-segment component according to claim 22, wherein the combustible heat source comprises a rear portion having a constant cross section, wherein at least one groove terminates at an upstream end of the rear portion. 24. The method of manufacturing a multi-segment component according to claim 22 or 23, wherein the radially outer edges of at least one longitudinal groove are curved with a radius of curvature of at least 0.05 mm. 25. A method of manufacturing a multi-segment component according to any one of paragraphs. 22-24, characterized in that the outer diameter of the combustible heat source is constant along the entire length of the combustible heat source. 26. A method of manufacturing a multi-segment component according to any one of paragraphs. 14-25, wherein the wrapper comprises a radially inner layer of thermally conductive material and a radially outer layer of thermally insulating material. 27. An aerosol generating product containing a multi-segment component according to any one of paragraphs. 1-13.

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