Aerosol generating article having a downstream element containing a novel filtration material.

Abstract

The aerosol generating article (10)(100)(1000) comprises an aerosol generating substrate (12)(112)(1004) and a downstream element (42)(150)(1008) provided downstream of the aerosol generating substrate (12)(112)(1004) and axially aligned with the aerosol generating substrate, the downstream element comprising a cellulosic filtration material. The fibrous material comprises a plurality of regenerated cellulose fibers selected from one or more of viscose fibers, modal fibers, lyocell fibers, and viscose rayon fibers, or a plurality of natural fibers selected from one or more of flax fibers, hemp fibers, jute fibers, kenaf fibers, ramie fibers, abaca fibers, phormium fibers, sisal fibers, coir fibers, cotton fibers, and kapok fibers. The cellulosic fibrous material further comprises an additive coating applied to multiple regenerated cellulose or natural fibers, the additive coating containing at least 5% by weight of exogenous lignin on a dry weight basis.

Description

Technical Field

[0001] The present invention relates to an aerosol-generating article having a downstream element formed of a novel biodegradable filter material.

Background Art

[0002] Conventional aerosol-generating articles such as cigarette paper with filters typically include a cylindrical rod of tobacco cut filler surrounded by a paper wrapper and a cylindrical filter that is axially aligned with the rolled tobacco rod, typically with ends abutting. The cylindrical filter typically includes one or more plug elements of a fibrous filter material such as cellulose acetate tow surrounded by a paper plug wrap. Conventionally, the rolled tobacco rod and filter are joined by a tipping wrapper band formed from a generally opaque paper material that surrounds the entire length of the filter and an adjacent portion of the rolled tobacco rod. In known filter-tipped cigarettes, the filter is typically adapted for the removal of particulate and gaseous components of the mainstream smoke.

[0003] A number of aerosol-generating articles in which the tobacco is heated rather than burned have also been proposed in the art. In heated aerosol-generating articles, the aerosol is generated by heating an aerosol-generating substrate such as tobacco. Known heated aerosol-generating articles include, for example, smoking articles in which the aerosol is generated by electrical heating or by heat transfer from a combustible fuel element or heat source to the aerosol-generating substrate. During smoking, volatile compounds are released from the aerosol-generating substrate by heat transfer from the heat source and entrained in the air drawn through the smoking article. The released compounds condense as they cool to form an aerosol and are inhaled by the consumer. Many known heated aerosol-generating articles include one or more elements formed of a fibrous filter material.

[0004] After aerosol-generating articles are smoked and discarded, it is desirable that their components, particularly any elements formed from fibrous filter materials, decompose as quickly as possible. However, cellulose acetate, the most commonly used fibrous filter material in aerosol-generating articles, is not biodegradable and can persist in the environment for many years. As a result, used cigarette filters made from cellulose acetate tend to accumulate in the environment and are the most commonly collected plastic items in beach cleanup activities. Therefore, it is desirable to provide more sustainable alternatives to cellulose acetate for producing aerosol-generating article components, particularly filter or mouthpiece components.

[0005] To address the environmental impact caused by post-consumer waste containing non-biodegradable plastics that are directly discarded into the environment, certain jurisdictions have introduced legislation banning single-use plastic products (SUPs). The term SUP refers to a product that is manufactured entirely or partially from plastic and is typically intended for use only once or for a short period before being discarded. Therefore, it is generally desirable to replace single-use plastics in aerosol-generating articles with natural, biodegradable alternatives.

[0006] A wide variety of alternative materials have already been proposed for use as filtration materials for aerosol-generating articles. However, in many cases, these alternative filtration materials have been found to fail to provide consumers with an acceptable filtration efficiency and smoking experience. In other cases, these alternative filtration materials have been found to lack hardness and processability. Furthermore, in many cases, dispersible and biodegradable materials have been found to be unsuitable for use in existing manufacturing processes, and their use would require excessively large modifications to existing methods and equipment to make them commercially viable.

[0007] Therefore, it is desirable to provide an aerosol-generating article comprising components that are at least partially formed of a filter material that has improved biodegradability but provides a filtration efficiency comparable to that of cellulose acetate tow. In particular, it is desirable that the components be formed of a biodegradable filter material that can still effectively reduce or remove undesirable compounds from aerosols generated from a substrate (e.g., phenol).

[0008] Furthermore, it is desirable to provide such aerosol-generating articles that give consumers an acceptable sensory experience. In particular, it is desirable that the components be made of biodegradable filter materials that have little to no effect on the taste perceived by consumers during the use of the aerosol-generating article and generally do not adversely affect the smoking experience.

[0009] Furthermore, it is desirable to provide such aerosol-generating articles that can be easily manufactured using existing high-speed manufacturing techniques and equipment that requires only minimal modifications.

[0010] Furthermore, it is desirable that the filtration material be capable of being effectively formed into components that provide a consumer-acceptable appearance and feel. For example, it is desirable that the filtration material be capable of being effectively formed into components for aerosol-generating articles that provide a desirable density, hardness, and draw-to-discharge (RTD). [Overview of the project]

[0011] This disclosure relates to an aerosol generating article. The aerosol generating article may comprise an aerosol generating substrate. The aerosol generating article may comprise a downstream element provided downstream of the aerosol generating substrate. The downstream element may comprise a cellulosic filter material. The cellulosic filter material may comprise a fibrous material comprising a plurality of regenerated cellulose fibers. The regenerated cellulose fibers may be one or more of viscose fibers, modal fibers, lyocell fibers, and viscose rayon fibers. The cellulosic filter material may further comprise an additive coating applied to the plurality of regenerated cellulose fibers. The additive coating may comprise at least 5% by weight of exogenous lignin on a dry weight basis.

[0012] This disclosure further relates to aerosol-generating articles. An aerosol-generating article may comprise an aerosol-generating substrate. An aerosol-generating article may comprise a downstream element provided downstream of the aerosol-generating substrate. The downstream element may comprise a cellulosic filter material. The cellulosic filter material may comprise a fibrous material comprising a plurality of natural fibers. The natural fibers may be one or more of flax fibers, hemp fibers, jute fibers, kenaf fibers, ramie fibers, abaca fibers, phormium fibers, sisal fibers, coir fibers, cotton fibers, and kapok fibers. The cellulosic filter material may further comprise an additive coating applied to the plurality of natural fibers. The additive coating may comprise at least 5 weight percent of exogenous lignin on a dry weight basis.

[0013] The present invention is defined in the following claims.

[0014] According to a first aspect of the present invention, an aerosol generating article is provided, comprising: an aerosol generating substrate; a downstream element provided downstream of the aerosol generating substrate and aligned axially with the aerosol generating substrate, wherein the downstream element comprises a fibrous material comprising a plurality of regenerated cellulose fibers, the regenerated cellulose fibers being one or more of viscose fibers, modal fibers, lyocell fibers, and viscose rayon fibers; and a cellulose-based filtration material comprising an additive coating applied to the plurality of regenerated cellulose fibers, the additive coating comprising at least 5 weight percent of exogenous lignin on a dry weight basis.

[0015] A second aspect of the present invention provides an aerosol generating article comprising: an aerosol generating substrate; a downstream element provided downstream of the aerosol generating substrate and aligned axially with the aerosol generating substrate, wherein the downstream element comprises a fibrous material comprising a plurality of natural fibers, the natural fibers being one or more of flax fibers, hemp fibers, jute fibers, kenaf fibers, ramie fibers, abaca fibers, phormium fibers, sisal fibers, coir fibers, cotton fibers, and kapok fibers; and a cellulose-based filter material comprising an additive coating applied to the plurality of natural fibers, the additive coating comprising an additive coating comprising at least 5 weight percent of exogenous lignin on a dry weight basis.

[0016] As used herein in connection with the present invention, the term "aerosol-generating article" is used to describe an article comprising an aerosol-generating substrate that generates and delivers a heated, inhalable aerosol to a user.

[0017] When used herein in connection with the present invention, the term "aerosol-generating substrate" is used to describe a substrate comprising an aerosol-generating material that can be released upon heating (including combustion) of a volatile compound capable of generating aerosols.

[0018] As used herein in connection with the present invention, the term “aerosol” is used to describe a dispersion of solid particles or droplets, or a combination of solid particles and droplets, in a gas. Aerosols may be visible or invisible. Aerosols may include vapors of substances that are normally liquid or solid at room temperature, as well as solid particles or droplets, or a combination of solid particles and droplets. As used herein, the term “aerosol” includes aerosols produced when a substrate is heated in a heated aerosol generating article, and smoke produced when a substrate is burned in a flammable smoking article.

[0019] When used herein in connection with the present invention, the term "aerosol generator" is used to describe a device that generates an aerosol by interacting with an aerosol-generating substrate of an aerosol-generating article.

[0020] The aerosol generating article according to the present invention has a proximal end through which the aerosol exits the aerosol generating article for delivery to the user during use. The proximal end of the aerosol generating article may also be referred to as the downstream end or mouth end of the aerosol generating article. During use, the user directly or indirectly inhales the proximal end of the aerosol generating article in order to inhale the aerosol generated by the aerosol generating article.

[0021] The aerosol-generating article according to the present invention has a distal end. The distal end is the opposite side of the proximal end. The distal end of the aerosol-generating article may also be referred to as the upstream end of the aerosol-generating article.

[0022] The components of the aerosol-generating article according to the present invention can be described as being upstream or downstream of each other based on their relative positions between the proximal end and the distal end of the aerosol-generating article.

[0023] As used herein in connection with this specification, the term "longitudinal direction" is used to describe the direction between the upstream end and the downstream end of an aerosol-generating article. During use, air is drawn longitudinally through the aerosol-generating article.

[0024] As used herein in connection with the present invention, the term "length" is used to describe the maximum dimension in the longitudinal direction of an aerosol-generating article or a component of an aerosol-generating article.

[0025] As used herein in connection with the present invention, the term "transverse direction" is used to describe a direction that is perpendicular to the longitudinal direction. Unless otherwise specified, the "cross-section" of an aerosol-generating article or a component of an aerosol-generating article refers to a cross-section.

[0026] As used herein in connection with the present invention, the term "width" refers to the maximum dimension in the transverse direction of an aerosol-generating article or a component of an aerosol-generating article. When the aerosol-generating article has a substantially circular cross-section, the width of the aerosol-generating article corresponds to the diameter of the aerosol-generating article. When a component of the aerosol-generating article has a substantially circular cross-section, the width of the component of the aerosol-generating article corresponds to the diameter of the component of the aerosol-generating article.

[0027] As used herein in connection with the present invention, the term "rod" is used to mean a generally cylindrical element having a substantially circular, oval or elliptical cross-section.

[0028] As used herein in connection with the present invention, the term "hollow tubular element" is used to represent a substantially cylindrical element having a tubular space along its longitudinal axis. The tubular portion may have a cross-section that is substantially circular, substantially oval, or substantially elliptical. The tubular space may have a cross-section that is substantially circular, substantially oval, or substantially elliptical. Specifically, the term "hollow tubular element" is used to represent an element that defines at least one air flow conduit establishing unbroken fluid communication between an upstream end of the hollow tubular element and a downstream end of the hollow tubular element.

[0029] Unless otherwise specified, the draw resistance (RTD) of a component or an aerosol generating article according to the present invention is measured in accordance with ISO6565-2015. RTD refers to the pressure required to pump air through the entire length of the component. The terms "pressure drop" or "draw resistance" of a component or article may also refer to "resistance to draw". Such terms generally refer to measurements in accordance with ISO6565-2015 and are normally carried out at a temperature of about 22 degrees Celsius, a pressure of about 101 kPa (about 760 Torr), and a relative humidity of about 60% with a volumetric flow rate of about 17.5 milliliters per second at the output or downstream end of the measured component.

[0030] The aerosol flow generated during use of an aerosol generating article is a complex mixture of chemicals, including semi-solid particles dispersed in a fluid matrix of vapors and permanent gases. As used herein in connection with the present invention, the term "filtration efficiency" is used to describe the ability of an element containing a filter material to capture particulate matter contained in such an aerosol flow. In practice, the term "filtration efficiency" means the proportion of the total dry particulate matter carried by the aerosol flow that is retained within the element containing the filter material during use.

[0031] As used herein, the term "phenol" refers to a class of compounds consisting of a hydroxyl group (-OH) directly bonded to an aromatic hydrocarbon group. Phenol groups include phenol, catechol, m+P-cresol, and o-cresol.

[0032] The present invention provides an improved aerosol-generating article comprising at least one downstream element formed of a cellulosic filtration material, which includes a combination of regenerated cellulose or natural fibers and an additive coating containing exogenous lignin. Therefore, the aerosol-generating article according to the present invention can advantageously be formed of more sustainable materials, containing reduced or zero levels of single-use plastics. In particular, the aerosol-generating article according to the present invention uses regenerated cellulose or natural fibers instead of cellulose acetate fibers to form elements such as filtration elements, thereby significantly improving the biodegradability of the aerosol-generating article.

[0033] The application of additive coatings to regenerated cellulose or natural fibers has been found to significantly improve the filtration characteristics of downstream elements. In particular, the use of additive coatings containing exogenous lignin has been found to significantly improve the reduction of phenols and other undesirable compounds from mainstream aerosols compared to the use of regenerated cellulose or natural fibers alone. The composition of the additive coatings can be advantageously modified to optimize the filtration efficiency of downstream elements, achieving reductions in phenols and other undesirable compounds similar to those achieved with conventional cellulose acetate tow.

[0034] The additive coating contains exogenous lignin and, optionally, one or more additional compounds that provide functional groups, such as acetyl groups, within the cellulosic filter material, which can act to directly remove phenols and other undesirable compounds from mainstream aerosols. Furthermore, the lignin and other optional components of the additive coating have been found to advantageously improve the properties of regenerated cellulose or natural fibers, so that the capture and retention of mainstream aerosol components can be further improved. For example, the inclusion of the additive coating has been found to advantageously cause a decrease in the glass transition temperature, which leads to an increase in the adsorption rate of compounds from mainstream aerosols.

[0035] Furthermore, the application of additive coatings to regenerated cellulose or natural fibers in cellulosic filtration materials has been found to offer benefits related to the physical properties of the fibers, which can facilitate the formation of downstream elements. For example, the application of additive coatings has been found to make the fibers more flexible, which facilitates the processing of cellulosic filtration materials. Additive coatings further improve the bonding between fibers, and as a result, downstream elements with desired density and hardness can be produced more easily.

[0036] It has been further found that additive coatings increase the hydrophobicity of regenerated cellulose or natural fibers, which in turn reduces the adsorption and capture of water from mainstream aerosols. This is beneficial because any significant reduction in the moisture content of mainstream aerosols delivered to consumers can result in the smoke or aerosol being perceived as an undesirable "dryness" that can negatively impact the overall smoking experience.

[0037] Overall, the combination of regenerated cellulose or natural fibers with additive coatings can produce downstream elements that are significantly more biodegradable than equivalent elements formed from cellulose acetate, while maintaining desirable levels of filtration and acceptable physical properties so that the inclusion of downstream elements does not negatively impact the consumer experience.

[0038] As defined above, the cellulosic filtration material forming the downstream element of the aerosol generating article according to the present invention comprises a fibrous material formed from a plurality of regenerated cellulose or natural fibers coated with an additive coating. The additive coating covers at least a portion of the outer surface of the regenerated cellulose or natural fibers and thus provides an outer coating layer on the fibers. The additive coating may be applied on a portion of the outer surface of the regenerated cellulose or natural fibers. Alternatively, the additive coating may be applied on substantially all of the outer surface of the regenerated cellulose or natural fibers. The application of the additive coating to the outer surface of the regenerated cellulose or natural fibers is advantageous in that it maximizes contact between the mainstream aerosol passing through the downstream element during use and the additive coating. This then maximizes the ability of the additive coating to reduce phenols and other undesirable compounds in the smoke or aerosol.

[0039] In the downstream element of the aerosol generating article of the present invention, the fibrous material forms the body of the downstream element. According to a first aspect of the present invention, the fibrous material comprises a plurality of regenerated cellulose fibers.

[0040] The term "regenerated cellulose fiber" is used herein to mean a cellulose fiber formed by processing a naturally occurring cellulose material to provide a cellulose fiber having desired physical properties. A typical process for forming regenerated cellulose fiber includes the steps of pulping a natural cellulose material, such as wood chips, to form pulp; subjecting the pulp to one or more processing steps to alter the physical properties of the cellulose; and forming fibers of the regenerated cellulose fiber from the processed pulp, for example, by passing the pulp through a spinneret.

[0041] For the purposes of the present invention, the regenerated cellulose fibers are selected from viscose fibers, modal fibers, lyocell fibers, and viscose rayon fibers, or combinations thereof. The fibrous material is particularly preferably composed of viscose fibers. In some embodiments, the fibrous material consists of viscose fibers.

[0042] Regenerated cellulose fibers containing acetate groups are particularly excluded from the scope of the present invention.

[0043] The fibrous material preferably contains at least 50 percent regenerated cellulose fibers, more preferably at least 60 percent regenerated cellulose fibers, more preferably at least 70 percent regenerated cellulose fibers, more preferably at least 80 percent regenerated cellulose fibers, and more preferably at least 90 percent regenerated cellulose fibers.

[0044] The fibrous material preferably contains at least 50 percent viscose fibers, more preferably at least 60 percent viscose fibers, more preferably at least 70 percent viscose fibers, more preferably at least 80 percent viscose fibers, and more preferably at least 90 percent viscose fibers.

[0045] The fibrous material is preferably composed of regenerated cellulose fibers such that regenerated cellulose fibers constitute 100 percent of the fibrous material and are not combined with any other type of fiber. Alternatively, the fibrous material may contain other fibers in addition to regenerated cellulose fibers. These additional fibers can be incorporated into the cellulosic filter material by mixing them with the regenerated cellulose fibers during the production of the cellulosic filter material. The additional fibers are preferably formed from biodegradable materials. Suitable types of additional fibers include, but are not limited to, natural cellulose fibers such as flax fibers, hemp fibers, jute fibers, kenaf fibers, ramie fibers, abaca fibers, phormium fibers, sisal fibers, coir fibers, cotton fibers, or kapok fibers.

[0046] According to a second aspect of the present invention, the fibrous material comprises a plurality of natural fibers.

[0047] In this specification, the term “natural fiber” is used to mean plant-derived fiber that is directly derived from a plant source and therefore not artificial. Natural fibers may be untreated. Alternatively, and preferably, natural fibers may be treated to improve their properties, for example, natural fibers may undergo mercerization before application of an additive coating, as will be discussed in more detail below.

[0048] For the purposes of the present invention, the natural fiber is a natural fiber selected from flax fiber, hemp fiber, jute fiber, kenaf fiber, ramie fiber, abaca fiber, phormium fiber, sisal fiber, coir fiber, cotton fiber, kapok fiber, or a combination thereof. The fibrous material is particularly preferably cotton fiber, or a combination of cotton fiber and kapok fiber. In certain embodiments of the present invention, the natural fiber includes mercerized fiber.

[0049] The fibrous material preferably contains at least 50 percent natural fibers, more preferably at least 60 percent natural fibers, more preferably at least 70 percent natural fibers, more preferably at least 80 percent natural fibers, and more preferably at least 90 percent natural fibers.

[0050] The fibrous material preferably contains at least 50 percent cotton fibers, more preferably at least 60 percent cotton fibers, more preferably at least 70 percent cotton fibers, more preferably at least 80 percent cotton fibers, and more preferably at least 90 percent cotton fibers.

[0051] The fibrous material is preferably composed of natural fibers such that natural fibers constitute 100 percent of the fibrous material and are not combined with any other types of fibers. Alternatively, the fibrous material may contain other fibers in addition to natural fibers. These additional fibers can be incorporated into the cellulosic filter material by mixing them with natural fibers during the production of the cellulosic filter material. The additional fibers are preferably formed from biodegradable materials. Suitable types of additional fibers include, but are not limited to, regenerated cellulose fibers such as viscose.

[0052] The following discussion concerning "fibrous materials" refers to both aspects of the present invention unless otherwise stated.

[0053] The fibrous material preferably does not contain cellulose acetate fibers or any other fibers formed from non-biodegradable polymers.

[0054] The fibrous material is preferably a nonwoven fabric. Regenerated cellulose or natural fibers are preferably formed into a fibrous tow material similar to that provided in conventional cellulose acetate filters.

[0055] The fibrous material preferably contains randomly oriented regenerated cellulose or natural fibers.

[0056] Advantageously, using filter materials containing randomly oriented fibers improves the decomposition of the filter material. This is because randomly oriented fibers can be dispersed more easily after the filter is discarded, especially compared to the substantially continuous filaments of conventional cellulose acetate tow filters. Increased fiber dispersion increases the exposure of individual fibers to the environment, and therefore further increases the rate at which the filter material elements decompose.

[0057] The random orientation of the fibers advantageously provides the necessary resistance to mechanical deformation of the filter material so that the downstream elements can withstand being gripped by the consumer during smoking of the aerosol-generating article. The random orientation of the fibers also provides the necessary draw resistance so that the smoking experience of the aerosol-generating article according to the present invention is substantially the same as the smoking experience using an aerosol-generating article having a conventional cellulose acetate tow filter.

[0058] The regenerated cellulose or natural fibers are preferably crimped staple fibers, which helps reduce the mechanical degradation of the fibers during processing of the filter material to form downstream elements and during the subsequent assembly of aerosol-generating articles. The fibers can be crimped using known methods for crimping woven fibers.

[0059] Regenerated cellulose or natural fibers may have a substantially round cross-section.

[0060] The regenerated cellulose or natural fibers preferably have a denier (dpf) of at least about 2.0, more preferably at least 2.5, more preferably at least 3.0, more preferably at least 3.2, more preferably at least 3.5, more preferably at least about 4.0, more preferably at least 4.5, and more preferably at least 5.0 per filament.

[0061] The regenerated cellulose or natural fiber preferably has a density of 10.0 denier or less per filament, more preferably 9.0 denier or less, more preferably 8.0 or less, and more preferably 7.0 or less.

[0062] The denier per filament corresponds to the average denier of individual PHA fibers in the filter and is the gram weight of a single fiber or filament having a length of 9000 meters. Therefore, in this invention, the dpf value indicates the thickness of each individual regenerated cellulose or natural fiber in the cellulosic filter material. The denier per filament is expressed in units of denier, where 1 denier corresponds to 1 gram per 9000 meters. The dpf of a filter or filter segment can be easily determined based on measurements of the weight and length of a representative fiber sample from the cellulosic filter material.

[0063] Preferably, the total denier of the cellulosic filter material, including regenerated cellulose or natural fibers, is about 20,000 to about 50,000, more preferably about 25,000 to about 40,000, and more preferably about 30,000 to about 40,000. The "total denier" of the filter material is defined in grams as the total weight of 9,000 meters of combined fibers forming the filter material. Therefore, the total denier of the cellulosic filter material corresponds to the denier per filament multiplied by the total number of fibers in the cellulosic filter material.

[0064] The cellulose-based filter material preferably contains at least 85% by weight of fibrous material, more preferably at least 88% by weight of fibrous material, more preferably at least 90% by weight of fibrous material, and more preferably at least 95% by weight of fibrous material.

[0065] The cellulose-based filter material preferably contains up to 99% by weight of fibrous material, more preferably up to 98% by weight of fibrous material, and more preferably up to 95% by weight of additive coating, on a dry weight basis.

[0066] Advantageously, regenerated cellulose or natural fibers may be treated with an additive enhancer before application of the additive coating. For example, regenerated cellulose may come into contact with the additive enhancer during fiber formation, such as during the extrusion or spinning process to form the fibers, or during drying or curing.

[0067] As used herein, the term “additive enhancer” refers to a compound that controls the polarity of regenerated cellulose or natural fibers in order to improve the retention of the additive coating on the surface of the fibers. Suitable additive enhancers include, but are not limited to, chitin and chitosan.

[0068] As defined above, in the cellulosic filtration material forming a downstream element of the aerosol generating article according to the present invention, the additive coating is applied to a plurality of regenerated cellulose or natural fibers such that the fibers are at least partially coated with the additive coating.

[0069] The cellulose-based filter material preferably contains at least 1 weight percent of additive coating on a dry weight basis, more preferably at least 2 weight percent of additive coating, more preferably at least 3 weight percent of additive coating, more preferably at least 4 weight percent of additive coating, and more preferably at least 5 weight percent of additive coating.

[0070] The cellulose-based filter material preferably contains up to 15 weight percent of additive coatings on a dry weight basis, more preferably up to 12 weight percent of additive coatings, and even more preferably up to 10 weight percent of additive coatings.

[0071] The additive coating includes at least one additive for reducing phenol. That is, the additive coating includes at least one additive having the ability to capture or otherwise convert at least a portion of the phenol and phenol derivatives produced in conjunction with the heating or combustion of the aerosol-generating substrate. Preferably, the additive coating includes at least one additive for reducing other undesirable compounds from mainstream aerosols such as carbon monoxide, carbon dioxide, and nitrogen oxides.

[0072] The additive coating is preferably biodegradable, so that the cellulosic filter material, including the combination of the additive coating and regenerated cellulose or natural fibers, is biodegradable.

[0073] According to the present invention, the additive coating contains at least 5 weight percent of exogenous lignin on a dry weight basis. Preferably, the additive coating contains at least 6 weight percent of exogenous lignin on a dry weight basis, more preferably at least 8 weight percent of exogenous lignin, more preferably at least 10 weight percent of exogenous lignin, more preferably at least 12 weight percent of exogenous lignin, and more preferably at least 15 weight percent of exogenous lignin.

[0074] The additive coating preferably contains up to 50 weight percent exogenous lignin on a dry weight basis, more preferably up to 45 weight percent exogenous lignin, more preferably up to 40 weight percent exogenous lignin, more preferably up to 35 weight percent exogenous lignin, and more preferably up to 30 weight percent.

[0075] For example, the additive coating may consist of 5% to 50% exogenous lignin by dry weight, or 6% to 50% exogenous lignin, or 8% to 50% exogenous lignin, or 10% to 50% exogenous lignin, or 12% to 50% exogenous lignin, or 15% to 50% exogenous lignin, or 5% to 45% exogenous lignin, or 6% exogenous lignin by dry weight. Exogenous lignin of 10% to 45% by weight, or 8% to 45% by weight, or 10% to 45% by weight, or 12% to 45% by weight, or 15% to 45% by weight, or 5% to 40% by weight, or 6% to 40% by weight, or 8% to 40% by weight, Lignin, or 10% to 40% by weight exogenous lignin, or 12% to 40% by weight exogenous lignin, or 15% to 40% by weight exogenous lignin, or 5% to 35% by weight exogenous lignin, or 6% to 35% by weight exogenous lignin, or 8% to 35% by weight exogenous lignin, or 10% to 35% by weight exogenous lignin, or 12% to 35% by weight It may also contain 1% exogenous lignin, or 15% to 35% by weight exogenous lignin, or 5% to 30% by weight exogenous lignin, or 6% to 30% by weight exogenous lignin, or 8% to 30% by weight exogenous lignin, or 10% to 30% by weight exogenous lignin, or 12% to 30% by weight exogenous lignin, or 15% to 30% by weight exogenous lignin.

[0076] Lignin provides numerous active functional groups capable of capturing phenols containing acetyl groups. Therefore, by including lignin in cellulosic filtration materials, the amount of phenol in the mainstream aerosol as it passes from the aerosol generating substrate to the downstream elements is reduced.

[0077] The above range refers to the amount of exogenous lignin in the additive coating. The term “exogenous” refers to any lignin incorporated into the additive coating that is provided in an isolated form, extracted, and separated from other components of the plant material from which it originates. Thus, exogenous lignin is provided exogenously from any cellulosic plant material present. In other words, this is a distinct and different lignin source to any lignin that is essentially provided within any plant material in the cellulosic filter material. The same definition of “exogenous” applies in relation to hemicellulose, as described below.

[0078] For the purposes of the present invention, exogenous lignin may be extracted from any plant source. For example, exogenous lignin may be extracted from straw pulp or wood pulp.

[0079] In certain preferred embodiments of the present invention, the exogenous lignin may be in the form of acetylated lignin. Acetylated lignin is a form of modified lignin that is modified to increase the number of acetyl groups. As a result of the increase in the number of acetyl groups, the use of acetylated lignin may further improve the ability of lignin to reduce phenol from mainstream aerosols.

[0080] While we do not wish to be bound by theory, it is understood that the introduction of acetyl groups also affects the wetting properties of cellulosic filter materials. In fact, the esterification reaction that occurs between acetyl groups and at least some hydroxyl groups in cellulose molecules induces a change from hydrophilic to hydrophobic properties in at least some regenerated cellulose or natural fibers. Therefore, regenerated cellulose or natural fibers coated with an additive coating containing acetylated lignin may have a reduced tendency to absorb moisture from smoke or aerosols flowing through the plug element. This may counteract the effect observed in some conventional cellulose acetate filters, often referred to as "dry smoke," which is desirable in that the smoke or aerosols delivered to consumers have a significantly reduced moisture content and are therefore perceived as undesirable dryness under certain conditions.

[0081] In certain preferred embodiments of the present invention, the exogenous lignin may be in the form of organosolublignin. Organosolublignin is lignin produced using organosolub pulping technology, which uses an aqueous organic solvent to solubilize the lignin. The use of organosolublignin is desirable due to its high purity and low ash content.

[0082] In certain preferred embodiments of the present invention, the exogenous lignin may be pale, nearly white, or white lignin. Such lignin is typically lighter than standard lignin, which is yellow or brown. The use of pale, nearly white, or white lignin may be advantageous because the exogenous lignin has a color similar to that of the fibrous material to which the additive coating is applied. Thus, the exogenous lignin is not visible within the cellulosic filter material, so that the overall appearance of the cellulosic filter material may resemble that of a conventional filter for a smoking article.

[0083] Suitable processes for producing pale, nearly white, or white lignin will be known to those skilled in the art. For example, a suitable process is disclosed in EP-A-3707194.

[0084] The cellulose-based filter material preferably contains at least 0.5 weight percent of exogenous lignin on a dry weight basis, more preferably at least 1 weight percent of exogenous lignin, more preferably at least 1.5 weight percent of exogenous lignin, and more preferably at least 2 weight percent of exogenous lignin.

[0085] The cellulose-based filter material preferably contains up to 8 weight percent exogenous lignin on a dry weight basis, more preferably up to 6 weight percent exogenous lignin, more preferably up to 5 weight percent exogenous lignin, and more preferably up to 4 weight percent exogenous lignin.

[0086] For example, cellulose-based filter materials contain 0.5% to 8% exogenous lignin, or 0.5% to 6% exogenous lignin, or 0.5% to 5% exogenous lignin, or 0.5% to 4% exogenous lignin, 1% to 8% exogenous lignin, or 1% to 6% exogenous lignin, or 1% to 5% exogenous lignin, or 1% to 4% exogenous lignin It may also contain 1.5 to 8 weight percent exogenous lignin, or 1.5 to 6 weight percent exogenous lignin, or 1.5 to 5 weight percent exogenous lignin, or 1.5 to 4 weight percent exogenous lignin, or 2 to 8 weight percent exogenous lignin, or 2 to 6 weight percent exogenous lignin, or 2 to 5 weight percent exogenous lignin, or 2 to 4 weight percent exogenous lignin.

[0087] The additive coating preferably further contains at least one polysaccharide.

[0088] At least one polysaccharide advantageously provides additional active functional groups, such as acetyl groups, which are particularly effective in capturing phenols and other undesirable gaseous compounds generated from the aerosol-generating substrate. Therefore, including additional polysaccharides in the additive coating, in addition to lignin, further reduces the levels of phenols and other undesirable gaseous compounds in the mainstream aerosol as it passes from the aerosol-generating substrate to the downstream element.

[0089] Polysaccharides can effectively bind to lignin within the additive coating, potentially providing an additive coating with improved temperature stability. Furthermore, the presence of lignin is thought to reduce the crystallinity and glass transition temperature of the polysaccharides, resulting in an increased ability of the polysaccharides to capture and store gas from mainstream aerosols and an increased rate of gas absorption.

[0090] At least one polysaccharide may include one or more plant-derived polysaccharides. Preferably, at least one polysaccharide includes plant-derived starch. For example, the additive coating preferably includes exogenous hemicellulose, corn starch, potato starch, or a combination thereof. In a particularly preferred embodiment, the additive coating includes hemicellulose. In another preferred embodiment, at least one polysaccharide includes corn starch. In another preferred embodiment, at least one polysaccharide includes modified starch such as acetylated starch or oxidized starch. In another preferred embodiment, at least one polysaccharide includes sugar or acetylated sugar.

[0091] Similar to what is described above in relation to acetylated lignin, it is understood that the addition of acetyl groups to starch or sugar molecules further affects the wetting properties of cellulosic filter materials. While we do not wish to be bound by theory, by reacting with some of the hydroxyl groups in the cellulose molecule, acetyl groups may contribute to shifting the properties of regenerated cellulose or natural fibers in cellulosic filter materials from hydrophilic to hydrophobic. This may be advantageous as it may reduce the tendency of cellulosic filter material elements to absorb moisture and capture nicotine from passing aerosols.

[0092] The additive coating preferably contains at least 20% by weight of at least one polysaccharide, more preferably at least 30% by weight of at least one polysaccharide, more preferably at least 40% by weight of at least one polysaccharide, and more preferably at least 50% by weight of at least one polysaccharide, on a dry weight basis.

[0093] The additive coating preferably contains at least one polysaccharide in a maximum of 90% by weight, more preferably at least one polysaccharide in a maximum of 85% by weight, and more preferably at least one polysaccharide in a maximum of 80% by weight, on a dry weight basis.

[0094] For example, the additive coating may contain, on a dry weight basis, at least one polysaccharide in an amount of 20% to 90% by weight, or at least one polysaccharide in an amount of 30% to 90% by weight, or at least one polysaccharide in an amount of 40% to 90% by weight, or at least one polysaccharide in an amount of 50% to 90% by weight, or at least one polysaccharide in an amount of 20% to 85% by weight, or at least one polysaccharide in an amount of 30% to 85% by weight, or at least one polysaccharide in an amount of 40% to 85% by weight, or at least one polysaccharide in an amount of 50% to 85% by weight, or at least one polysaccharide in an amount of 20% to 80% by weight, or at least one polysaccharide in an amount of 30% to 80% by weight, or at least one polysaccharide in an amount of 40% to 80% by weight, or at least one polysaccharide in an amount of 50% to 80% by weight.

[0095] The cellulose-based filter material preferably contains at least 1 weight percent of at least one polysaccharide on a dry weight basis, more preferably at least 2 weight percent of at least one polysaccharide, more preferably at least 5 weight percent of at least one polysaccharide, and even more preferably at least 6 weight percent of at least one polysaccharide.

[0096] The cellulose-based filter material preferably contains, on a dry weight basis, at least 15% by weight of at least one exogenous polysaccharide, more preferably at least 12% by weight of at least one exogenous polysaccharide, more preferably at least 10% by weight of at least one exogenous polysaccharide, and more preferably at least 8% by weight of at least one exogenous polysaccharide.

[0097] For example, cellulose-based filter materials contain, on a dry weight basis, at least one polysaccharide in 1 to 15 weight percent, or at least one polysaccharide in 1 to 12 weight percent, or at least one polysaccharide in 1 to 10 weight percent, or at least one polysaccharide in 1 to 8 weight percent, or at least one polysaccharide in 2 to 15 weight percent, or at least one polysaccharide in 2 to 12 weight percent, or at least one polysaccharide in 2 to 10 weight percent, or at least one polysaccharide in 2 to 8 weight percent. It may also contain another polysaccharide, or at least one polysaccharide in 5 to 15 weight percent, or at least one polysaccharide in 5 to 12 weight percent, or at least one sugar in 5 to 10 weight percent, or at least one polysaccharide in 5 to 8 weight percent, or at least one polysaccharide in 6 to 15 weight percent, or at least one polysaccharide in 6 to 12 weight percent, or at least one polysaccharide in 6 to 10 weight percent, or at least one polysaccharide in 6 to 8 weight percent.

[0098] The weight ratio of at least one polysaccharide to exogenous lignin in the additive coating is preferably at least 2, more preferably at least 2.5, more preferably at least 3, more preferably at least 3.5, and more preferably at least 4. The weight ratio of at least one exogenous polysaccharide to exogenous lignin in the additive coating may be up to 6.

[0099] The additive coating preferably contains exogenous hemicellulose. The additive coating preferably contains at least 5% by weight of exogenous hemicellulose on a dry weight basis, more preferably at least 6% by weight of exogenous hemicellulose, more preferably at least 8% by weight of exogenous hemicellulose, and more preferably at least 10% by weight of exogenous hemicellulose.

[0100] The additive coating preferably contains up to 50 weight percent exogenous hemicellulose on a dry weight basis, more preferably up to 45 weight percent exogenous hemicellulose, more preferably up to 40 weight percent exogenous hemicellulose, more preferably up to 35 weight percent exogenous hemicellulose, and more preferably up to 30 weight percent hemicellulose.

[0101] For example, the additive coating may consist of 5% to 50% by weight exogenous hemicellulose, or 6% to 50% by weight exogenous hemicellulose, or 8% to 50% by weight exogenous hemicellulose, or 10% to 50% by weight exogenous hemicellulose, or 5% to 45% by weight exogenous hemicellulose, or 6% to 45% by weight exogenous hemicellulose, or 8% to 45% by weight exogenous hemicellulose, or 10% to 45% by weight exogenous hemicellulose, or 5% to 40% by weight exogenous hemicellulose, or 6% to 40% by weight exogenous hemicell It may contain rose, or 8 to 40 weight percent exogenous hemicellulose, or 10 to 40 weight percent exogenous hemicellulose, or 5 to 35 weight percent exogenous hemicellulose, or 6 to 35 weight percent exogenous hemicellulose, or 8 to 35 weight percent exogenous hemicellulose, or 10 to 35 weight percent exogenous hemicellulose, or 5 to 30 weight percent exogenous hemicellulose, or 6 to 30 weight percent exogenous hemicellulose, or 8 to 30 weight percent exogenous hemicellulose, or 10 to 30 weight percent exogenous hemicellulose.

[0102] Hemicellulose provides numerous active functional groups capable of capturing phenol and other undesirable gaseous compounds generated from aerosol-generating substrates. Therefore, including hemicellulose in addition to lignin in cellulosic filtration materials further reduces the levels of phenol and certain other undesirable gaseous compounds in the mainstream aerosol as it passes from the aerosol-generating substrate to the downstream element.

[0103] For the purposes of the present invention, exogenous hemicellulose may be extracted from any plant source. For example, exogenous hemicellulose may be extracted from straw pulp or wood pulp. Lignin and hemicellulose may be extracted from the same plant source.

[0104] The cellulosic filtration material preferably contains at least 0.5 weight percent of exogenous hemicellulose on a dry weight basis, more preferably at least 1 weight percent of exogenous hemicellulose, more preferably at least 1.5 weight percent of exogenous hemicellulose, and more preferably at least 2 weight percent of exogenous hemicellulose.

[0105] The cellulose-based filter material preferably contains up to 8 weight percent exogenous hemicellulose on a dry weight basis, more preferably up to 6 weight percent exogenous hemicellulose, more preferably up to 5 weight percent exogenous hemicellulose, and more preferably up to 4 weight percent exogenous hemicellulose.

[0106] For example, cellulosic filtration materials may contain, on a dry weight basis, 0.5 to 8 weight percent exogenous hemicellulose, or 0.5 to 6 weight percent exogenous hemicellulose, or 0.5 to 5 weight percent exogenous hemicellulose, or 0.5 to 4 weight percent exogenous hemicellulose, or 1 to 8 weight percent exogenous hemicellulose, or 1 to 6 weight percent exogenous hemicellulose, or 1 to 5 weight percent exogenous hemicellulose, or 1 to 4 weight percent exogenous hemicellulose It may also contain cellulose, or 1.5 to 8 weight percent of exogenous hemicellulose, or 1.5 to 6 weight percent of exogenous hemicellulose, or 1.5 to 5 weight percent of exogenous hemicellulose, or 1.5 to 4 weight percent of exogenous hemicellulose, or 2 to 8 weight percent of exogenous hemicellulose, or 2 to 6 weight percent of exogenous hemicellulose, or 2 to 5 weight percent of exogenous hemicellulose, or 2 to 4 weight percent of exogenous hemicellulose.

[0107] The combined amount of exogenous lignin and exogenous hemicellulose in the additive coating is at least 10% by weight, more preferably at least 12% by weight, more preferably at least 14% by weight, more preferably at least 16% by weight, and more preferably at least 18% by weight, on a dry weight basis.

[0108] The combined amount of exogenous lignin and exogenous hemicellulose in the additive coating is preferably up to 50% by weight, more preferably up to 45% by weight, more preferably up to 40% by weight, more preferably up to 35% by weight, and more preferably up to 30% by weight, on a dry weight basis.

[0109] For example, the combined amount of exogenous lignin and exogenous hemicellulose in the additive coating may be 10% to 50% by weight, or 12% to 45% by weight, or 14% to 40% by weight, or 16% to 35% by weight, or 18% to 30% by weight, on a dry weight basis.

[0110] The combined amount of exogenous lignin and exogenous hemicellulose in the cellulosic filtration material is preferably at least 1% by weight, more preferably at least 1.5% by weight, more preferably at least 2% by weight, and more preferably at least 2.5% by weight, on a dry weight basis.

[0111] The combined amount of exogenous lignin and exogenous hemicellulose in the cellulosic filtration material is preferably up to 10% by weight, more preferably up to 8% by weight, more preferably up to 6% by weight, and more preferably up to 4% by weight, on a dry weight basis.

[0112] For example, the combined amount of exogenous lignin and exogenous hemicellulose in a cellulosic filter material may be 1% to 10% by weight, or 1.5% to 8% by weight, or 2% to 6% by weight, or 2.5% to 4% by weight, on a dry weight basis.

[0113] Alternatively, the additive coating may further contain at least one monosaccharide or disaccharide derivative, such as sucrose isobutyric acid acetate.

[0114] At least one monosaccharide or disaccharide derivative advantageously provides additional active functional groups, such as acetyl and carboxymethyl groups, which are particularly effective in capturing phenol and other undesirable gaseous compounds generated from the aerosol-generating substrate. Therefore, including additional monosaccharide or disaccharide derivatives in the additive coating, in addition to lignin or lignin / polysaccharide mixtures, further reduces the levels of phenol and other undesirable gaseous compounds in the mainstream aerosol as it passes from the aerosol-generating substrate to the downstream element.

[0115] Monosaccharide or disaccharide derivatives have also been found to advantageously improve the hydrophobicity and temperature stability of cellulosic filter materials.

[0116] Preferably, the additive coating contains, on a dry weight basis, at least 20 weight percent of at least one monosaccharide derivative or disaccharide derivative, more preferably at least 30 weight percent of at least one monosaccharide derivative or disaccharide derivative, more preferably at least 40 weight percent of at least one monosaccharide derivative or disaccharide derivative, and more preferably at least 50 weight percent of at least one monosaccharide derivative or disaccharide derivative.

[0117] Preferably, the additive coating contains, on a dry weight basis, at least 90% by weight of at least one monosaccharide derivative or disaccharide derivative, more preferably at least 85% by weight of at least one monosaccharide derivative or disaccharide derivative, and more preferably at least 80% by weight of at least one monosaccharide derivative or disaccharide derivative.

[0118] For example, the additive coating contains, on a dry weight basis, at least one monosaccharide or disaccharide derivative in an amount of 20% to 90% by weight, or at least one monosaccharide or disaccharide derivative in an amount of 30% to 90% by weight, or at least one monosaccharide or disaccharide derivative in an amount of 40% to 90% by weight, or at least one monosaccharide or disaccharide derivative in an amount of 50% to 90% by weight, or at least one monosaccharide or disaccharide derivative in an amount of 20% to 85% by weight, or at least one monosaccharide or disaccharide derivative in an amount of 30% to 85% by weight The material may also contain derivatives, or at least one monosaccharide derivative or disaccharide derivative in an amount of 40% to 85% by weight, or at least one monosaccharide derivative or disaccharide derivative in an amount of 50% to 85% by weight, or at least one monosaccharide derivative or disaccharide derivative in an amount of 20% to 80% by weight, or at least one monosaccharide derivative or disaccharide derivative in an amount of 30% to 80% by weight, or at least one monosaccharide derivative or disaccharide derivative in an amount of 40% to 80% by weight, or at least one monosaccharide derivative or disaccharide derivative in an amount of 50% to 80% by weight.

[0119] Alternatively, or additionally, the additive coating may further include at least one crosslinking agent. Preferably, at least one crosslinking agent provides effective crosslinking of lignin and polysaccharides (if present).

[0120] Therefore, the inclusion of at least one crosslinking agent increases the viscosity of the additive coating, which in turn makes it easier to apply to fibers. The inclusion of at least one crosslinking agent also improves the ability of the additive coating to bond together regenerated cellulose or natural fibers in fibrous materials. Advantageously, the inclusion of at least one crosslinking agent can improve the hydrophobicity and temperature stability of cellulosic filter materials. Certain crosslinking agents may further provide active functional groups for capturing phenol and other undesirable gaseous compounds generated from aerosol-generating substrates. This can further increase the level of reduction of phenol and other undesirable gaseous compounds in mainstream aerosols as they pass from the aerosol-generating substrates to downstream elements.

[0121] Suitable crosslinking agents include, but are not limited to, acetic anhydride, succinic anhydride, pyridine, triacetin, or combinations thereof.

[0122] The additive coating preferably contains at least 0.1 weight percent of at least one crosslinking agent on a dry weight basis, more preferably at least 0.2 weight percent of at least one crosslinking agent, more preferably at least 0.3 weight percent of at least one crosslinking agent, and more preferably at least 0.5 weight percent of at least one crosslinking agent.

[0123] The additive coating preferably contains at least one crosslinking agent in an amount of up to 10 weight percent, more preferably up to 5 weight percent, and more preferably up to 2 weight percent, on a dry weight basis.

[0124] For example, the additive coating may contain, on a dry weight basis, at least one crosslinking agent in an amount of 0.1 to 10 weight percent, or at least one crosslinking agent in an amount of 0.2 to 10 weight percent, or at least one crosslinking agent in an amount of 0.3 to 10 weight percent, or at least one crosslinking agent in an amount of 0.5 to 10 weight percent, or at least one crosslinking agent in an amount of 0.1 to 5 weight percent, or at least one crosslinking agent in an amount of 0.2 to 5 weight percent, or at least one crosslinking agent in an amount of 0.3 to 5 weight percent, or at least one crosslinking agent in an amount of 0.5 to 5 weight percent, or at least one crosslinking agent in an amount of 0.1 to 2 weight percent, or at least one crosslinking agent in an amount of 0.2 to 2 weight percent, or at least one crosslinking agent in an amount of 0.3 to 2 weight percent, or at least one crosslinking agent in an amount of 0.5 to 2 weight percent.

[0125] The cellulose-based filter material preferably contains at least 0.001 weight percent of at least one crosslinking agent on a dry weight basis, more preferably at least 0.005 weight percent of at least one crosslinking agent, more preferably at least 0.01 weight percent of at least one crosslinking agent, and more preferably at least 0.02 weight percent of at least one crosslinking agent.

[0126] The cellulose-based filter material preferably contains at least one crosslinking agent in an amount of up to 3 weight percent, more preferably up to 2 weight percent, more preferably up to 1 weight percent, and more preferably up to 0.1 weight percent, on a dry weight basis.

[0127] For example, the cellulose-based filter material may contain, on a dry weight basis, at least one crosslinking agent in an amount of 0.001 to 3 weight percent, or at least one crosslinking agent in an amount of 0.005 to 0.2 weight percent, or at least one crosslinking agent in an amount of 0.01 to 0.1 weight percent, or at least one crosslinking agent in an amount of 0.02 to 0.05 weight percent.

[0128] To prepare the additive coating, lignin is preferably combined with other optional components of the additive coating and formed with water into a slurry. The slurry may be heated to bring about any desired reaction between the components of the additive coating.

[0129] The additive coating may be applied to regenerated cellulose or natural fibers in any preferred manner. Preferably, the additive coating is applied to the regenerated cellulose or natural fibers by spraying it onto the fibers while the fibers are forming in the downstream element. Alternatively, the additive coating may be injected into the regenerated cellulose or natural fibers, for example, after the fibers have formed in the downstream element. After the additive coating is applied to the fibers, the coated fibers are preferably dried by any preferred means, including conventional heating or microwave heating. Any curing of the additive coating may also be performed during this drying process.

[0130] As described above, the present invention further provides a method for producing a cellulosic filtration material for forming a downstream element of an aerosol generating article according to the first embodiment of the present invention. The method includes the steps of: providing a plurality of regenerated cellulose fibers; forming an additive coating solution in water containing at least 5% by weight of exogenous lignin and optionally one or more polysaccharides on a dry weight basis; applying the additive coating solution to the plurality of regenerated cellulose fibers; and drying and optionally curing the coated fibers.

[0131] The process of providing multiple regenerated cellulose fibers may include forming the regenerated cellulose fibers in a spinning or extrusion process. Advantageously, the multiple regenerated cellulose fibers may be formed in the presence of an additive enhancer, as defined above. The additive enhancer may be applied to the regenerated cellulose fibers before any drying of the regenerated cellulose fibers. Alternatively, the regenerated cellulose fibers may be dried before the application of the additive enhancer.

[0132] As described above, the present invention further provides a method for producing a cellulosic filtration material for forming a downstream element of an aerosol generating article according to the present invention in a second aspect. The method comprises the steps of: providing a plurality of natural fibers; forming an additive coating solution in water containing at least 5 weight percent of exogenous lignin and optionally one or more polysaccharides on a dry weight basis; applying the additive coating solution to the plurality of natural fibers; and drying and optionally curing the coated fibers.

[0133] Multiple natural fibers may be mercerized before the step of applying the additive coating solution. Mercerization is a well-known process for treating cellulosic natural fibers, particularly cotton fibers, in which the natural fibers are immersed in a strong alkaline solution, such as a sodium hydroxide solution. Mercerization of natural fibers is known to improve the properties of the fibers and, in relation to the present invention, may also advantageously improve the adhesion of the additive coating to the surface of the fibers. Additionally, mercerization of fibers improves the hydrophobicity of cellulosic fibrous materials.

[0134] Advantageously, multiple natural fibers may be treated with the additive enhancer defined above before applying the additive coating.

[0135] In all methods according to the present invention, the additive coating solution is formed by combining the dry components of the additive coating and dispersing or dissolving them in water. The dry components include, as described above, exogenous lignin, optionally one or more polysaccharides, and optionally one or more crosslinking agents. The additive coating solution may optionally be heated before application to regenerated cellulose or natural fibers to induce any desired reactions, for example, between the components of the additive coating.

[0136] The step of applying the additive coating solution to regenerated cellulose or natural fibers may include spraying the additive coating solution onto the surface of multiple regenerated cellulose or natural fibers.

[0137] The steps of drying the coated fibers and optionally curing them may include heating the coated fibers using a conventional heater. Alternatively, or additionally, the steps of drying the coated fibers and optionally curing them may include heating the coated fibers by microwave heating. Drying and optionally curing of the additive coating solution are performed to evaporate water from the solution and result in curing and hardening of the additive coating.

[0138] The downstream element of the aerosol generating article according to the present invention preferably includes a segment of cellulosic filtration material surrounded by a wrapper such as a paper wrapper. The segment of cellulosic filtration material is preferably in the form of a solid plug. Alternatively, as will be described in more detail below, the segment of cellulosic filtration material may be in the form of a hollow tubular segment.

[0139] The wrapper surrounding the cellulosic filter material may have a basis weight of at least 50 grams / square meter (gsm). If the downstream element is located at the downstream end of the aerosol-generating article, this may help provide the aerosol-generating article with the desired hardness. In some embodiments, it may be desirable to use a rigid wrapper, for example, a wrapper having a basis weight of at least about 80 grams / square meter (gsm), or at least about 100 gsm, or at least about 110 gsm.

[0140] The downstream element containing the cellulose-based filter material preferably has an average radial hardness of at least 75 percent, more preferably at least 80 percent, and more preferably at least 85 percent. The downstream element preferably has a radial hardness of less than 100 percent, more preferably less than 95 percent. This makes it possible to provide an aerosol-generating article with a downstream end having a hardness satisfactory to consumers.

[0141] As used herein, the term “radial hardness” refers to resistance to compression in a direction transverse to the longitudinal axis. The radial hardness of an aerosol-generating article around a filter can be determined by applying a load across the article at the filter's location, transverse to the article's longitudinal axis, and by measuring the average (mean) of the compressed diameter of the article. Radial hardness is given by:

number

[0142] To determine the hardness of a portion of an aerosol article (such as a filter), the aerosol-generating articles should be aligned parallel to each other in a plane, and the same portion of each aerosol-generating article being tested should be subjected to a set load for a set duration. This test is performed using the well-known DD60A Densimeter apparatus (manufactured and commercially available by Heinr. Borgwaldt GmbH (Germany)), which is equipped with a measuring head for aerosol-generating articles such as cigarettes and also comes with an aerosol-generating article container.

[0143] The standard operating procedure for such a device involves applying an overall load of 2 kg for 20 seconds. After 20 seconds (while the load is still applied to the smoking article), the pressure on the load-applying cylindrical rod is determined and then used to calculate the hardness from the equation described above. The temperature is maintained within the range of 22 degrees Celsius ± 2 degrees. The above test is called the DD60A test. The standard method for measuring filter hardness is when the aerosol-generating article has not yet been consumed. Additional information regarding the measurement of mean radial hardness can be found, for example, in U.S. Patent Application No. 2016 / 0128378.

[0144] As described above, downstream elements containing cellulosic filtration materials offer the advantage of improved biodegradability compared to conventional cellulose acetate segments.

[0145] The downstream element preferably contains substantially no cellulose acetate.

[0146] As briefly described above, the downstream element is provided downstream of the aerosol generating substrate and aligned axially with the aerosol generating substrate.

[0147] In some embodiments, the aerosol generating article is essentially formed from an aerosol generating substrate and the aforementioned downstream elements provided in a manner that abuts a rod of the aerosol generating substrate. For example, the aerosol generating substrate may be in the form of a cylindrical rod of shredded tobacco material surrounded by a wrapper, and the downstream elements may be attached to a rod wrapped with a strip of chipping paper to form a mouthpiece of the aerosol generating article.

[0148] In other embodiments, the aerosol-generating article comprises one or more additional elements provided downstream of the aerosol-generating substrate and axially aligned with the aerosol-generating substrate. The downstream elements and any further elements provided downstream of the aerosol-generating substrate and axially aligned with the aerosol-generating substrate form the downstream section of the aerosol-generating article.

[0149] In some preferred embodiments, the downstream element is a mouthpiece element.

[0150] The aerosol generating article may be equipped with a mouthpiece at its downstream end, oral end, or proximal end, and the mouthpiece consists only of the downstream element.

[0151] Alternatively, the aerosol generating article may be provided with a mouthpiece at its downstream end, oral end, or proximal end, the mouthpiece comprising a downstream element and one or more further elements aligned axially with end to end touching each other. The downstream element and the one or more further elements may be formed of the same material. Alternatively, the one or more further elements may be formed of a material other than that of the downstream element.

[0152] The parameters or characteristics described herein with respect to downstream elements may be equally applicable to downstream elements used as one of several components of a mouthpiece.

[0153] Advantageously, the aerosol generating article according to the present invention, in which the downstream element is a mouthpiece element, provides an acceptable visual and tactile experience for the consumer due to the density and hardness of the downstream element. Furthermore, in the aerosol generating article according to the present invention, in which the downstream element is a mouthpiece element, the cellulosic filtration material has the ability to efficiently reduce undesirable compounds (e.g., phenol) from the aerosol generated from the substrate, with little to no effect on the taste perceived by the consumer during use of the aerosol generating article. Thus, the aerosol generating article according to the present invention, in which the downstream element is a mouthpiece element, provides a more sustainable alternative to aerosol generating articles containing a cellulose acetate filter segment as the mouthpiece filter segment.

[0154] The mouthpiece element may have low particle phase filtration efficiency, or may have substantially no particle phase filtration efficiency. While having the ability to prevent substrate material from the aerosol-generating substrate from reaching the consumer's mouth during use, a mouthpiece element with low particle phase filtration efficiency has a reduced impact on the delivery of aerosol species to the consumer. This is particularly advantageous in aerosol-generating articles where the aerosol-generating substrate is heated rather than burned.

[0155] In a preferred embodiment, the particle phase filtration efficiency of the downstream element is less than about 30 percent, and more preferably less than about 20 percent.

[0156] In some embodiments, the mouthpiece element may have an RTD of about 25 mmH2O or less, about 20 mmH2O or less, or about 15 mmH2O or less. In such embodiments, the mouthpiece element may have an RTD of at least about 10 mmH2O.

[0157] The mouthpiece element may have an RTD of approximately 10 mmH2O to 25 mmH2O, approximately 10 mmH2O to 20 mmH2O, or approximately 10 mmH2O to 15 mmH2O.

[0158] The mouthpiece element preferably has a substantially circular cross-section.

[0159] Preferably, the mouthpiece element has substantially the same outer diameter as the outer diameter of the aerosol-generating article.

[0160] The length of the mouthpiece may be at least approximately 3 millimeters, or at least approximately 5 millimeters.

[0161] The length of the mouthpiece element may be approximately 11 millimeters or less, or approximately 9 millimeters or less.

[0162] The length of the mouthpiece element may be approximately 3 mm to 11 mm, or approximately 3 mm to 9 mm. The length of the mouthpiece element may also be approximately 5 mm to 11 mm, or approximately 5 mm to 9 mm. For example, the length of the mouthpiece element may be approximately 7 mm.

[0163] The length of the mouthpiece element may be selected based on the desired overall length of the aerosol-generating article.

[0164] The mouthpiece element may be surrounded by a plug wrap.

[0165] The mouthpiece element may not be ventilated to prevent air from entering the aerosol-generating item along the mouthpiece element.

[0166] The mouthpiece element may be connected by a chipping wrapper to one or more adjacent components of the aerosol-generating article.

[0167] The aerosol generating article may define an oral end cavity at its downstream end. For example, the mouthpiece element itself may be in the form of a hollow tubular element. Alternatively, the mouthpiece may include the aforementioned non-hollow downstream element immediately upstream of the hollow tubular segment provided at the downstream end of the mouthpiece. As a further alternative, the oral end cavity may be defined by an outer wrapper of the mouthpiece extending beyond the downstream end of the aforementioned downstream element.

[0168] In some embodiments, the downstream element may be an additional element provided downstream of the aerosol generating substrate other than the mouthpiece element. That is, the aerosol generating article comprises a mouthpiece, and the downstream element is provided between the aerosol generating substrate and the mouthpiece of the aerosol generating article.

[0169] For example, the downstream element may be a support element provided immediately downstream of the aerosol generating substrate, preferably adjacent to the aerosol generating substrate. One such support element is adapted to provide structural strength to the aerosol generating article. Advantageously, the support element is configured to resist the downstream movement of the aerosol generating substrate during the insertion of the heating element of the aerosol generating device into the aerosol generation.

[0170] In some embodiments, the downstream element may form part of an aerosol cooling element provided downstream of the aerosol generating substrate, which is adapted to facilitate the cooling of aerosols generated during use of the aerosol generating article before reaching the downstream end of the aerosol generating article.

[0171] The aerosol cooling element preferably has low draw resistance. That is, the aerosol cooling element preferably provides low resistance to the air passage through the aerosol generating article. Preferably, the aerosol cooling element does not substantially affect the draw resistance of the aerosol generating article.

[0172] At least one of the support element and the aerosol cooling element may be in the form of a hollow tubular element formed from the cellulosic filtration material described above. In some embodiments, both the support element and the aerosol cooling element are in the form of a hollow tubular element, which may differ in length, inner diameter, or both.

[0173] In the aerosol-generating articles according to the present invention, such hollow tubular elements provide an unrestricted flow channel. This means that the hollow tubular elements provide a negligible level of RTD. As used herein in relation to the present invention, the term “negligible level of RTD” is used to describe an RTD of less than 1 mmH2O per 10 mm of length of the hollow tubular substrate element, less than 0.4 mmH2O per 10 mm of length of the hollow tubular substrate element, or less than 0.1 mmH2O per 10 mm of length of the hollow tubular substrate element. Therefore, the flow channel should not contain any components that would obstruct the airflow in the longitudinal direction. Preferably, the flow channel is substantially empty.

[0174] The hollow tubular element may have an overall length of at least about 10 millimeters, at least about 12 millimeters, or at least about 15 millimeters.

[0175] The hollow tubular element may have a total length of approximately 30 mm or less, 25 mm or less, or approximately 23 mm or less.

[0176] The hollow tubular element may have an overall length of approximately 10 mm to 30 mm, approximately 10 mm to 25 mm, or approximately 10 mm to 23 mm. The hollow tubular element may have an overall length of approximately 12 mm to 30 mm, approximately 12 mm to 25 mm, or approximately 12 mm to 23 mm. The hollow tubular element may have an overall length of approximately 12 mm to 30 mm, approximately 12 mm to 25 mm, or approximately 12 mm to 23 mm.

[0177] The total length of the hollow tubular element or multiple elements may be selected based on the desired total length of the aerosol-generating article.

[0178] In some embodiments, the ventilation zone may be provided downstream of the aerosol generating substrate.

[0179] For example, cooling of the smoke flow generated during the combustion of an aerosol-generating substrate can be achieved by providing a ventilation zone along the mouthpiece of the aerosol-generating article.

[0180] As another example, the ventilation zone may be located along the hollow tubular elements forming the cooling element. While we do not wish to be bound by theory, the temperature reduction resulting from introducing cooler outside air into the aerosol-generating article downstream of the aerosol-generating element through the ventilation zone may have a favorable effect on the nucleation and growth of aerosol particles.

[0181] The ventilation zone may include, for example, a plurality of perforations provided through the tubular wall of a hollow tubular element. The ventilation zone may comprise at least one row of circumferential perforations. The ventilation zone may comprise two rows of perforations around the periphery. Each circumferential row of perforations comprises 8 to 30 perforations.

[0182] In some embodiments, the downstream section of the aerosol generating article may include, in a continuous order, a support element, an aerosol cooling element, and a mouthpiece. Preferably, one or more of the support element, aerosol cooling element, and mouthpiece are in the form of the downstream element described above.

[0183] In some embodiments, the aerosol-generating article comprises an upstream section located upstream of the aerosol-generating substrate. The upstream section is preferably located immediately upstream of the aerosol-generating substrate. The upstream section preferably extends from the upstream end of the aerosol-generating article to the upstream end of the aerosol-generating substrate. The upstream section preferably includes an upstream element located immediately upstream of the rod of the aerosol-generating substrate.

[0184] If the aerosol-generating substrate contains shredded tobacco, such as tobacco cut filler, the upstream section or its components may additionally help prevent the loss of loose tobacco particles from the upstream end of the article.

[0185] The upstream section or its upstream element may also provide some degree of additional protection to the aerosol-generating substrate during storage, by covering at least to some extent the upstream end of the aerosol-generating substrate which may otherwise be exposed. In the case of an aerosol-generating article intended to be inserted into a cavity in an aerosol generator so that the aerosol-generating substrate can be externally heated within the cavity, the upstream section or its upstream element may advantageously facilitate the insertion of the upstream end of the article into the cavity.

[0186] The upstream elements of the upstream section may be made of any material suitable for use in an aerosol-generating article. Suitable materials for the upstream elements include filter materials, ceramics, polymer materials, cellulose acetate, cardboard, zeolites, or aerosol-generating substrates.

[0187] In a preferred embodiment, the upstream element may include a cellulosic filtration material comprising a fibrous material containing a plurality of regenerated cellulose fibers, wherein the regenerated cellulose fibers are one or more of viscose fibers, modal fibers, lyocell fibers, and viscose rayon fibers, and an additive coating applied to the plurality of regenerated cellulose fibers, the additive coating containing at least 5 weight percent of exogenous lignin on a dry weight basis. For example, the upstream element may be formed of the same cellulosic filtration material as the downstream element described above in relation to the first aspect of the present invention.

[0188] In other preferred embodiments, the upstream element may include a cellulosic filter material comprising a fibrous material containing a plurality of natural fibers, wherein the natural fibers are one or more of flax fibers, hemp fibers, jute fibers, kenaf fibers, ramie fibers, abaca fibers, phormium fibers, sisal fibers, coir fibers, cotton fibers, and kapok fibers; and an additive coating applied to the plurality of natural fibers, wherein the additive coating contains at least 5 weight percent of exogenous lignin on a dry weight basis. For example, the upstream element may be formed of the same cellulosic filter material as the downstream element described above in relation to a second aspect of the present invention.

[0189] From an environmental perspective, this is advantageous in that a larger portion of the aerosol-generating article as a whole is more easily decomposable. Furthermore, from a manufacturing perspective, it is advantageous to form different components of the same aerosol-generating article from the same material, as adjustments to the settings of existing equipment are generally not required.

[0190] The upstream section or its upstream element preferably has an outer diameter approximately equal to the outer diameter of the aerosol-generating article. Preferably, the outer diameter of the upstream section or its upstream element is about 6 mm to about 8 mm, and more preferably about 7 mm to about 7.5 mm. Preferably, the upstream section or its upstream element has an outer diameter of about 7.1 mm.

[0191] Preferably, the upstream section or upstream element has a length of about 2 mm to about 8 mm, more preferably about 3 mm to about 7 mm, and more preferably about 4 mm to about 6 mm. In a particularly preferred embodiment, the upstream section or upstream element has a length of about 5 mm. The length of the upstream section or upstream element may be advantageously varied to provide the desired total length of the aerosol-generating article.

[0192] The upstream section is preferably surrounded by a wrapper such as a plug wrap. The wrapper surrounding the upstream section is preferably a rigid plug wrap, for example, a plug wrap having a basis weight of at least about 80 grams / square meter (gsm), or at least about 100 gsm, or at least about 110 gsm. This provides increased structural rigidity to the upstream section.

[0193] The upstream section is preferably connected by an outer wrapper to the rods of the aerosol generating substrate and, optionally, to at least a portion of the downstream section.

[0194] The aerosol-generating article may be a flammable smoking article. A flammable smoking article typically comprises a cylindrical rod of tobacco cut filler enclosed in a paper wrapper, and an axially aligned cylindrical filter, most often end-to-end in contact with the wrapped tobacco rod. The cylindrical filter typically includes one or more plug elements of fibrous filter material enclosed in a paper plug wrapper. The rolled tobacco rod and the filter are typically joined by a strip of chipping wrapper that encloses the entire length of the filter and adjacent portions of the rolled tobacco rod. In the flammable smoking article according to the present invention, the cylindrical filter comprises a downstream element having the characteristics described above.

[0195] An aerosol generating article may be an aerosol generating article (heat-activated aerosol generating article) that generates an aerosol upon heating. A heat-activated aerosol generating article typically comprises a cylindrical rod of an aerosol generating substrate enclosed by a paper wrapper, and a downstream section of the aerosol generating substrate downstream of the rod. The downstream section typically includes at least one hollow tubular element immediately downstream of the rod of the aerosol generating substrate, and a mouthpiece.

[0196] The aerosol-generating article preferably has an overall length of 40 mm to 80 mm, or 40 mm to about 70 mm, or 40 mm to about 60 mm, or 45 mm to about 80 mm, or about 45 mm to about 70 mm, or 45 mm to about 60 mm, or 50 mm to 80 mm, or 50 mm to about 70 mm, or about 50 mm to about 60 mm. In an exemplary embodiment, the overall length of the aerosol-generating article is about 45 mm.

[0197] The aerosol-generating article preferably has a substantially circular cross-section.

[0198] The aerosol-generating article preferably has an outer diameter of about 5 mm to about 12 mm, or about 6 mm to about 12 mm, or about 7 mm to about 12 mm, or about 5 mm to about 10 mm, or about 6 mm to about 10 mm, or about 7 mm to about 10 mm, or about 5 mm to about 8 mm, or about 6 mm to about 8 mm, or about 7 mm to about 8 mm. In other embodiments, the aerosol-generating article has an outer diameter of less than 7 mm.

[0199] The overall RTD of the aerosol-generating article is preferably at least 10 mmH2O, more preferably at least 15 mmH2O, more preferably at least 20 mmH2O, more preferably at least 25 mmH2O, and more preferably at least 30 mmH2O.

[0200] The overall RTD of the aerosol-generating article is preferably 70 mmH2O or less, more preferably 60 mmH2O or less, more preferably 55 mmH2O or less, more preferably 50 mmH2O or less, and more preferably 45 mmH2O or less.

[0201] For example, the overall RTD of an aerosol-generating article could be 10 mmH2O to 70 mmH2O, or 15 mmH2O to 60 mmH2O, or 20 mmH2O to 55 mmH2O, or 25 mmH2O to 45 mmH2O, or 30 mmH2O to 45 mmH2O.

[0202] As described above, the aerosol generating article according to the present invention comprises an aerosol generating substrate. In some embodiments, the aerosol generating article comprises a rod of the aerosol generating substrate surrounded by a rod plug wrap.

[0203] Preferably, the rod of the aerosol generating substrate has a length of at least 8 millimeters, more preferably at least 9 millimeters, and more preferably at least 10 millimeters. Preferably, the length of the rod of the aerosol generating substrate is less than 16 millimeters, more preferably less than 15 millimeters, and more preferably less than 14 millimeters. For example, the rod of the aerosol generating substrate may have a length of 8 to 16 millimeters, or 9 to 15 millimeters, or 10 to 14 millimeters. In a particularly preferred embodiment, the rod of the aerosol generating substrate has a length of about 12 millimeters.

[0204] The ratio of the length of the rod of the aerosol generating substrate to the total length of the aerosol generating article is preferably at least 0.10, more preferably at least 0.15, more preferably at least 0.20, and more preferably at least 0.25. Preferably, the ratio of the length of the rod of the aerosol generating substrate to the total length of the aerosol generating article is less than 0.50, more preferably less than 0.45, more preferably less than 0.40, and more preferably less than 0.35. For example, the ratio of the length of the rod of the aerosol generating substrate to the total length of the aerosol generating article may be 0.1 to 0.5, or 0.15 to 0.45, or 0.2 to 0.4, or 0.25 to 0.35.

[0205] The rod of the aerosol generating substrate preferably has an outer diameter that is approximately equal to the outer diameter of the aerosol generating article.

[0206] Preferably, the rod of the aerosol generating substrate has an outer diameter of at least 5 mm, more preferably at least 6 mm, and more preferably at least 7 mm. Preferably, the rod of the aerosol generating substrate has an outer diameter of less than 12 mm, more preferably less than 10 mm, and more preferably less than 8 mm. For example, the outer diameter may be between 5 mm and 12 mm, or between 6 mm and 10 mm, or between 7 mm and 8 mm. In a particularly preferred embodiment, the rod of the aerosol generating substrate has an outer diameter of about 7.1 mm.

[0207] The rod of the aerosol generating substrate preferably has a substantially uniform cross-section along its length. It is particularly preferable that the rod of the aerosol generating substrate has a substantially circular cross-section.

[0208] The aerosol-generating substrate may have a density of at least about 150 milligrams / cubic centimeter, at least about 175 milligrams / cubic centimeter, at least about 200 milligrams / cubic centimeter, or at least or about 250 milligrams / cubic centimeter.

[0209] The aerosol generating substrate may have a density of approximately 500 milligrams / cubic centimeter or less, approximately 450 milligrams / cubic centimeter or less, approximately 400 milligrams / cubic centimeter or less, or approximately 350 milligrams / cubic centimeter or less.

[0210] The RTD of the aerosol generating substrate rod may be at least about 4 mmH2O, at least about 5 mmH2O, or at least about 6 mmH2O.

[0211] The RTD of the aerosol generating substrate rod may be approximately 10 mmH2O or less, approximately 9 mmH2O or less, or approximately 8 mmH2O or less.

[0212] The aerosol generating substrate may be a solid aerosol generating substrate. Suitable types of materials for use in the aerosol generating substrate are described below and include, for example, homogenized tobacco materials such as tobacco cut filler and cast leaf, aerosol generating films, and gel compositions.

[0213] The aerosol generating substrate preferably includes an aerosol-forming agent. Suitable aerosol-forming agents include, for example, polyhydric alcohols (e.g., triethylene glycol, 1,3-butanediol, propylene glycol, glycerin, etc.), esters of polyhydric alcohols (e.g., glycerol mono-, di-, or triacetate, etc.), aliphatic esters of mono-, di-, or polycarboxylic acids (e.g., dimethyl dodecanediate, dimethyl tetradecanediate, etc.), and combinations thereof.

[0214] The aerosol-forming body preferably contains one or more of glycerin and propylene glycol. The aerosol-forming body may consist of glycerin, propylene glycol, or a combination of glycerin and propylene glycol.

[0215] In certain embodiments, the aerosol generating substrate preferably contains at least 5 weight percent of aerosol-forming material on a dry weight basis of the aerosol generating substrate, more preferably at least 10 weight percent on a dry weight basis, and even more preferably at least 15 weight percent on a dry weight basis. In such embodiments, the aerosol generating substrate preferably contains 30 weight percent or less of aerosol-forming material on a dry weight basis of the aerosol generating substrate, more preferably 25 weight percent or less on a dry weight basis, and more preferably 20 weight percent or less on a dry weight basis. For example, the aerosol-forming material content of the aerosol generating substrate may be 5 weight percent to 30 weight percent, or 10 weight percent to 25 weight percent, or about 15 weight percent to about 20 weight percent on a dry weight basis. Therefore, in such embodiments, the aerosol-forming material content is relatively low.

[0216] In other embodiments, the aerosol generating substrate preferably contains at least 40 weight percent of aerosol forming material on a dry weight basis of the aerosol generating substrate, more preferably at least 45 weight percent on a dry weight basis, and more preferably at least 50 weight percent on a dry weight basis. In such embodiments, the aerosol generating substrate preferably contains 80 weight percent or less of aerosol forming material on a dry weight basis of the aerosol generating substrate, more preferably 75 weight percent or less on a dry weight basis, and more preferably 70 weight percent or less on a dry weight basis. For example, the aerosol forming material content of the aerosol generating substrate may be 40 weight percent to 80 weight percent, or 45 weight percent to 75 weight percent, or 50 weight percent to 70 weight percent on a dry weight basis. Therefore, in such embodiments, the aerosol forming material content is relatively high.

[0217] In some preferred embodiments, the aerosol generating substrate includes tobacco material. For example, the aerosol generating substrate may include shredded tobacco material. For example, the shredded tobacco material may be in the form of cut fillers, as will be described in more detail below. Alternatively, the shredded tobacco material may be in the form of shredded sheets of homogenized tobacco material. Preferred homogenized tobacco materials for use in the present invention are described below.

[0218] In the context of this specification, the term “cut filler” is used to refer to a blend of shredded plant material, such as tobacco plant material comprising one or more of the following: leaf laminas, processed stems and veins, and homogenized plant material.

[0219] The cut filler suitable for use in the present invention may generally be similar to the cut filler used in conventional smoking articles. The cutting width of the cut filler may preferably be 0.3 mm to 2.0 mm, or 0.5 mm to 1.2 mm, or 0.6 mm to 0.9 mm.

[0220] Preferably, the strands have a length of about 10 mm to about 40 mm, and the strands are then arranged to form a rod of aerosol generating substrate.

[0221] The cut filler is preferably immersed in an aerosol-forming body. Immersion of the cut filler can be carried out by spraying or by other suitable application methods. Preferably, the aerosol-forming body in the cut filler comprises one or more glycerol and propylene glycol. The aerosol-forming body may consist of glycerol, or propylene glycol, or a combination of glycerin and propylene glycol.

[0222] In other preferred embodiments, the aerosol generating substrate comprises homogenized plant material, preferably homogenized tobacco material.

[0223] As used herein, the term “homogenized plant material” encompasses any plant material formed by the aggregation of plant particles. For example, a sheet or web made of homogenized tobacco material for an aerosol generating substrate of the present invention may be formed by aggregating particles of tobacco material obtained by crushing, grinding, or pulverizing a plant material and optionally one or more thin layers of tobacco leaves and / or tobacco leaf stems. Homogenized plant material can be produced by molding, extrusion, papermaking processes, or any other suitable process known in the art.

[0224] Homogenized plant material can be provided in any preferred form.

[0225] In some embodiments, the homogenized plant material may be in the form of one or more sheets. As used herein in relation to the present invention, the term “sheet” refers to a layered element having a width and length substantially greater than its thickness.

[0226] The homogenized plant material may be in the form of multiple pellets or granules.

[0227] Homogenized plant material may be in the form of multiple strands, strips, or shreds. As used herein, the term “strand” refers to an elongated element of the material having a length substantially greater than its width and thickness.

[0228] The aerosol-forming content of the homogenized tobacco material is preferably within the range defined above for aerosol-generating substrates having a relatively low aerosol-forming content.

[0229] In other preferred embodiments, the aerosol generating substrate is in the form of an aerosol generating film comprising a cellulosic film-forming agent, nicotine, and an aerosol-forming agent. The aerosol generating film may further contain a cellulosic reinforcing agent. The aerosol generating film may further contain water, preferably less than 30% by weight.

[0230] As used herein, the term “film” is used to describe a solid layered element having a thickness less than its width or length. A film may be self-supporting.

[0231] In the context of the present invention, the term "cellulose-based film-forming agent" is used to refer to a cellulose polymer having the ability to form a continuous film, either by itself or in the presence of an auxiliary thickener. Preferably, the cellulose-based film-forming agent is selected from the group consisting of hydroxypropyl methylcellulose (HPMC), methylcellulose (MC), ethylcellulose (EC), hydroxyethyl methylcellulose (HEMC), hydroxyethylcellulose (HEC), hydroxypropylcellulose (HPC), and combinations thereof. In a particularly preferred embodiment, the cellulose-based film-forming agent is HPMC.

[0232] The aerosol-forming material content of the aerosol-generating film is within the range defined above for aerosol-generating substrates having a relatively high aerosol-forming material content.

[0233] Aerosol-generating films suitable for use as an aerosol-generating substrate in an aerosol-generating article according to the present invention are described in WO-A-2020 / 207733 and WO-A-2022 / 074157.

[0234] Preferably, the aerosol generating film contains 0.5% to 10% by weight of nicotine, or 1% to about 8% by weight of nicotine, or about 2% to about 6% by weight of nicotine, on a dry weight basis.

[0235] The aerosol generating film may be a substantially tobacco-free aerosol generating film.

[0236] In alternative embodiments of the present invention, the aerosol-generating substrate may include a gel composition comprising nicotine, at least one gelling agent, and an aerosol-forming body. The gel composition is preferably substantially free of tobacco.

[0237] The preferred weight range of nicotine in the gel composition is the same as that defined above in relation to the aerosol generating film.

[0238] A suitable gel composition for use as an aerosol generating substrate in an aerosol generating article according to the present invention is described in WO-A-2021 / 170642.

[0239] The gel composition preferably contains at least 50 weight percent, more preferably at least 60 weight percent, and more preferably at least 70 weight percent, of aerosol-forming material on a dry weight basis. The gel composition may contain up to 80 weight percent of aerosol-forming material. The aerosol-forming material in the gel composition is preferably glycerol.

[0240] In certain embodiments of the present invention, the aerosol generating article further includes one or more elongated susceptor elements within a rod of the aerosol generating substrate. For example, one or more elongated susceptor elements may be arranged substantially along their longitudinal axis within the aerosol generating rod and may be in thermal contact with the aerosol generating substrate.

[0241] As used herein in relation to the present invention, the term "susceptor element" refers to a material capable of converting electromagnetic energy into heat.

[0242] Suitable susceptor elements for use in the aerosol generating substrate of the aerosol generating article according to the present invention are described in WO-A-2021 / 170673.

[0243] Preferably, the rod of the aerosol generating substrate is surrounded by a wrapper. The wrapper may be a paper wrapper or a non-paper wrapper.

[0244] Suitable paper wrappers for use in specific embodiments of the present invention are known in the art and include, but are not limited to, cigarette papers and filter plug wrappers. Suitable non-paper wrappers for use in specific embodiments of the present invention are known in the art and include, but are not limited to, sheets of homogenized tobacco material.

[0245] According to a second aspect of the present invention, an aerosol generating system is provided comprising an aerosol generating article according to the first aspect of the present invention and an aerosol generating device configured to heat the aerosol generating substrate of the aerosol generating article.

[0246] The aerosol generator includes means for heating the aerosol generating substrate to a temperature sufficient to generate aerosols from the aerosol generating substrate. Preferably, the aerosol generator comprises a housing defining a cavity configured to receive an aerosol generating article, and means for heating the aerosol generating substrate to a temperature sufficient to generate aerosols from the aerosol generating substrate when the aerosol generating article is received in the cavity.

[0247] The aerosol generator could be a handheld aerosol generator.

[0248] The aerosol generator may be an electrically operated aerosol generator.

[0249] The aerosol generator may include a power supply and control electronics.

[0250] The aerosol generator may include a battery and control electronics.

[0251] The aerosol generator may be configured to internally heat the aerosol generating substrate. That is, the aerosol generator may be configured to supply heat to the aerosol generating substrate from a position inside the aerosol generating article.

[0252] For example, in some embodiments, the aerosol generator includes a heater element configured to be inserted into the aerosol generating element when an aerosol generating article is received into the cavity of the aerosol generator.

[0253] In other embodiments, the aerosol generating article comprises a susceptor element provided at a location within the aerosol generating element, the aerosol generating device comprises an inductor coil located on or within the housing, and the power supply for the aerosol generating device is connected to the inductor coil and configured to supply a high-frequency oscillating current to the inductor coil.

[0254] The aerosol generator may be configured to externally heat the aerosol generating substrate. That is, the aerosol generator may be configured to supply heat to the aerosol generating substrate from a location outside the aerosol generating article. For example, in some embodiments, the aerosol generator includes a heater element located around the periphery of a cavity and configured to heat the aerosol generating substrate of the aerosol generating article from outside the aerosol generating element of the aerosol generating article.

[0255] Here, we will further describe the embodiment with reference to the attached drawings. [Brief explanation of the drawing]

[0256] [Figure 1] Figure 1 shows a schematic side cross-sectional view of an aerosol generating article according to an embodiment of the present invention. [Figure 2] Figure 2 shows a schematic side cross-sectional view of another aerosol generating article according to another embodiment of the present invention. [Figure 3] Figure 3 shows a schematic side cross-sectional view of another aerosol-generating article according to a further embodiment of the present invention. [Modes for carrying out the invention]

[0257] The aerosol generating article 1000 shown in Figure 1 comprises an aerosol generating element 1002 in the form of a substantially cylindrical rod 1004 of shredded tobacco surrounded by a wrapper 1006. Furthermore, the aerosol generating article 1000 comprises a substantially cylindrical mouthpiece 1008 including a segment 1010 of cellulosic filter material surrounded by a plug wrap 1012.

[0258] The mouthpiece 1008 is attached to the aerosol generating element 1002 by a strip of chipping paper 1014. Perforations 1016 formed through the chipping paper and plug wrap are provided to allow ventilation air to enter the segment 1010 when the consumer inhales the mouthpiece 1008 during use. The aerosol generating article 1000 has a length of 70 mm and an outer diameter of 7.6 mm.

[0259] Segment 1010 is in the form of a plug element containing a cellulosic filter material. An example of a suitable cellulosic filter material includes viscose fibers and an additive coating applied to the viscose fibers, wherein the additive coating contains at least 5% by weight of exogenous lignin on a dry weight basis. A further example of a suitable cellulosic filter material includes cotton fibers and an additive coating applied to the cotton fibers, wherein the additive coating contains at least 5% by weight of exogenous lignin on a dry weight basis.

[0260] The aerosol generating article 10 shown in Figure 2 comprises a rod 12 of an aerosol generating base 12 and a downstream section 14 located downstream of the rod 12 of the aerosol generating base. Furthermore, the aerosol generating article 10 includes an upstream section 16 located upstream of the rod 12 of the aerosol generating base. Thus, the aerosol generating article 10 extends from the upstream or distal end 18 to the downstream or oral end 20 and has a total length of approximately 45 millimeters.

[0261] The downstream section 14 includes a support element 22 located immediately downstream of the rod 12 of the aerosol generating substrate, and the support element 22 is aligned with the rod 12 in the longitudinal direction. In the embodiment of Figure 2, the upstream end of the support element 18 abuts against the downstream end of the rod 12 of the aerosol generating substrate. In addition, the downstream section 14 includes an aerosol cooling element 24 located immediately downstream of the support element 22, and the aerosol cooling element 24 is aligned with the rod 12 and the support element 22 in the longitudinal direction. In the embodiment of Figure 1, the upstream end of the aerosol cooling element 24 abuts against the downstream end of the support element 22. In the embodiment of Figure 2, the support element 22 and the aerosol cooling element 24 together define an intermediate hollow section 50 of the aerosol generating article 10.

[0262] The support element 22 includes a first hollow tubular segment 26. The first hollow tubular segment 26 is provided in the form of a hollow cylindrical tube made of a filter material. The first hollow tubular segment 26 defines an internal cavity 28 that extends entirely from the upstream end 30 of the first hollow tubular segment 20 to the downstream end 32 of the first hollow tubular segment 20. The internal cavity 28 is substantially empty, and therefore substantially unlimited airflow is possible along the internal cavity 28.

[0263] The first hollow tubular segment 26 has a length of approximately 8 millimeters, an outer diameter of approximately 7.25 millimeters, and an inner diameter of approximately 1.9 millimeters. Therefore, the thickness of the peripheral wall of the first hollow tubular segment 26 is approximately 2.67 millimeters.

[0264] The aerosol cooling element 24 comprises a second hollow tubular segment 34. The second hollow tubular segment 34 is provided in the form of a hollow cylindrical tube made of a filter material. The second hollow tubular segment 34 defines an internal cavity 36 that extends all the way from the upstream end 38 of the second hollow tubular segment 34 to the downstream end 40 of the second hollow tubular segment 34. The internal cavity 36 is substantially empty, and therefore substantially unlimited airflow is possible along the internal cavity 36.

[0265] The second hollow tubular segment 34 has a length of approximately 8 millimeters, an outer diameter of approximately 7.25 millimeters, and an inner diameter of approximately 3.25 millimeters. Therefore, the thickness of the peripheral wall of the second hollow tubular segment 34 is approximately 2 millimeters. Thus, the ratio between the inner diameter of the first hollow tubular segment 26 and the inner diameter of the second hollow tubular segment 34 is approximately 0.75.

[0266] The aerosol-generating article 10 includes a ventilation zone 60 provided along the second hollow tubular segment 34. More specifically, the ventilation zone is provided approximately 2 millimeters from the upstream end of the second hollow tubular segment 34. The ventilation level of the aerosol-generating article 10 is approximately 25 percent.

[0267] In the embodiment shown in Figure 2, the downstream section 14 further includes a mouthpiece element 42 located downstream of the intermediate hollow section 50. More specifically, the mouthpiece element 42 is positioned immediately downstream of the aerosol cooling element 24. As shown in the drawing of Figure 2, the upstream end of the mouthpiece element 42 abuts against the downstream end 40 of the aerosol cooling element 18.

[0268] The mouthpiece element 42 is provided in the form of a cylindrical plug element 44 containing a cellulosic filter material. An example of a suitable cellulosic filter material includes viscose fibers and an additive coating applied to the viscose fibers, the additive coating containing at least 5% by weight of exogenous lignin on a dry weight basis. A further example of a suitable cellulosic filter material includes cotton fibers and an additive coating applied to the cotton fibers, the additive coating containing at least 5% by weight of exogenous lignin on a dry weight basis.

[0269] The mouthpiece element 42 has a length of approximately 12 millimeters and an outer diameter of approximately 7.25 millimeters.

[0270] Rod 12 contains one of the aerosol-generating substrates of the type described above.

[0271] The rod 12 of the aerosol generating substrate has an outer diameter of approximately 7.25 millimeters and a length of approximately 12 millimeters.

[0272] The aerosol generating article 10 further comprises an elongated susceptor 46 within the rod 12 of the aerosol generating substrate. More specifically, the susceptor 46 is disposed substantially along the longitudinal axis within the aerosol generating substrate so as to be substantially parallel to the longitudinal axis of the rod 12. As shown in the drawing of Figure 2, the susceptor 46 is positioned radially centrally within the rod and extends effectively along the longitudinal axis of the rod 12. More specifically, the susceptor 46 is in thermal contact with the aerosol generating substrate. The susceptor 46 extends along the entire length of the rod 12 from the upstream end to the downstream end. In practice, the susceptor 46 has substantially the same length as the rod 12 of the aerosol generating substrate.

[0273] More specifically, in the embodiment shown in Figure 2, the susceptor 46 is provided in the form of a strip, having a length of about 12 millimeters, a thickness of about 60 micrometers, and a width of about 4 millimeters.

[0274] The upstream section 16 includes an upstream element 48 located immediately upstream of the rod 12 of the aerosol generating substrate, and the upstream element 48 is aligned with the rod 12 in the longitudinal direction. In the embodiment shown in Figure 2, the downstream end of the upstream element 48 abuts against the upstream end of the rod 12 of the aerosol generating substrate. This advantageously prevents the susceptor 46 from detaching. Furthermore, this ensures that consumers cannot accidentally come into contact with the heated susceptor 46 after use.

[0275] The upstream element 48 includes a segment 50 of material in the form of a cylindrical plug of filtration material and a first wrapper 52 surrounding the segment 50 of material. The segment 50 of material has a length of approximately 5 millimeters. The RTD of the segment 50 of material is approximately 30 millimeters of H2O.

[0276] The aerosol generating article 10 further comprises a coupling wrapper 54 that attaches the upstream element 48 to the remaining components of the aerosol generating article. In the embodiment shown in Figure 2, a single coupling wrapper 54 is illustrated that surrounds and holds together the upstream element 48, the rod 12, and the downstream section 14 to form the aerosol generating article.

[0277] However, it will be clear that alternative configurations are possible, employing two or more binding wrappers to assemble different components of the aerosol generating article. For example, a first binding wrapper can be used to attach the support element 22 to the aerosol cooling element 24, and the resulting assembly can then be attached to the upstream section 16 and rod 12 by a second binding wrapper. The resulting combination of components can then be attached to the mouthpiece element 42 by a chipping wrapper. As shown in the drawing of Figure 1, the aerosol generating article 10 further comprises a wrapper 70 surrounding the rod 12 of the aerosol generating substrate. The wrapper 70 is separate from and distinct from the first wrapper 52 surrounding the material segment 50. Neither the first wrapper 52 nor the wrapper 70 contains metal foil.

[0278] In the aerosol generating article 10 of Figure 2, one or more of the first hollow tubular segment 26 of the support element 22, the second hollow tubular segment 34 of the aerosol cooling element 24, and the material segment 50 of the upstream element 48 may be made of the same material according to the present invention used in the mouthpiece element 42.

[0279] The aerosol generating article 100 shown in Figure 3 comprises an aerosol generating base rod 112 and a downstream section 114 located downstream of the aerosol generating base rod 112. In addition, the aerosol generating article 100 comprises an upstream section 116. Thus, the aerosol generating article 100 extends from an upstream or distal end 118 substantially coinciding with the upstream end of the upstream section 116 to a downstream or oral end 120 coinciding with the downstream end of the downstream section 114. The downstream section 114 includes a hollow tubular element 122 and a mouthpiece element 150. The upstream section 116 includes an upstream plug element 124.

[0280] The aerosol generating article 100 has an overall length of approximately 45 mm and an outer diameter of approximately 7.2 mm.

[0281] The aerosol generating substrate rod 112 contains shredded tobacco material. The aerosol generating substrate rod 112 contains 150 milligrams of shredded tobacco material containing 13 to 16 weight percent glycerin. The density of the aerosol generating substrate is approximately 300 mg per cubic centimeter. The ready-to-drink (RTD) of the aerosol generating substrate rod 112 is approximately 6 to 8 mmH2O. The aerosol generating substrate rod 112 is individually packaged with a plug wrap (not shown).

[0282] The hollow tubular element 122 is located immediately downstream of the rod 112 of the aerosol generating substrate, and is aligned with the rod 112 in the longitudinal direction. The upstream end of the hollow tubular element 122 abuts against the downstream end of the rod 112 of the aerosol generating substrate.

[0283] The hollow tubular element 122 defines the hollow section of the aerosol-generating article 110. The hollow tubular element 122 does not substantially contribute to the overall RTD of the aerosol-generating article. More specifically, the RTD of the hollow tubular element 122 is approximately 0 mmH2O.

[0284] As shown in Figure 3, the hollow tubular element 122 is provided in the form of a hollow cylindrical tube made of cardboard. The hollow tubular element 122 defines an internal cavity that extends throughout from the upstream end to the downstream end of the hollow tubular element 122. The internal cavity is substantially empty, and therefore allows for substantially unrestricted airflow along the internal cavity.

[0285] The hollow tubular element 122 has a length of approximately 21 millimeters, an outer diameter of approximately 7.2 millimeters, and an inner diameter of approximately 6.7 millimeters. Therefore, the thickness of the peripheral wall of the hollow tubular element 122 is approximately 0.25 millimeters.

[0286] The aerosol-generating article 100 includes a ventilation zone 160 provided along a hollow tubular element 122. The ventilation zone 160 includes a circumferential row of openings or perforations surrounding the hollow tubular element 122. The perforations of the ventilation zone 160 extend through the walls of the hollow tubular element 122 to allow fluid to enter the internal cavity from the outside of the article 100. The ventilation level of the aerosol-generating article 10 is approximately 16 percent.

[0287] On the rod 112 of the aerosol generating substrate and the downstream section 14 located downstream of the rod 12, the aerosol generating article 100 has an upstream section 140 located upstream of the rod 112. Thus, the aerosol generating article 10 extends from a distal end 116 substantially coinciding with the upstream end of the upstream section 140 to a mouth end or downstream end 118 substantially coinciding with the downstream end of the downstream section 114.

[0288] As briefly described above, the upstream section 116 includes an upstream plug element 124 located immediately upstream of the rod 112 of the aerosol generating substrate, and the upstream plug element 124 is aligned with the rod 112 in the longitudinal direction. The downstream end of the upstream plug element 124 abuts against the upstream end of the rod 112 of the aerosol generating substrate. The upstream plug element 124 has a wall thickness of about 1 mm and is provided in the form of a hollow cylindrical plug of filter material defining an upstream internal cavity. The upstream element 124 has a length of about 5 mm. The outer diameter of the upstream plug element 124 is about 7.1 mm. The inner diameter of the upstream plug element 42 is about 5.1 mm.

[0289] The mouthpiece element 150 extends from the downstream end of the hollow tubular element 122 to the downstream end or oral end of the aerosol generating article 100. The mouthpiece element 150 has a length of approximately 7 mm. The outer diameter of the mouthpiece element 150 is approximately 7.2 mm.

[0290] The mouthpiece element 150 is provided in the form of a cylindrical plug element containing a cellulosic filter material. An example of a suitable cellulosic filter material includes viscose fibers and an additive coating applied to the viscose fibers, the additive coating containing at least 5% by weight of exogenous lignin on a dry weight basis. A further example of a suitable cellulosic filter material includes cotton fibers and an additive coating applied to the cotton fibers, the additive coating containing at least 5% by weight of exogenous lignin on a dry weight basis.

[0291] In the aerosol generating article 100 shown in Figure 3, the plug element 124 of the upstream section 116 may be made of the same material according to the present invention used in the mouthpiece element 150.

[0292] For the purposes of this specification and the appended claims, unless otherwise indicated, all numerical values ​​representing quantities, amounts, percentages, etc., should be understood in all examples as being modified by the term “approximately.” Furthermore, all ranges include the disclosed maximum and minimum values, as well as any intermediate ranges contained within them, whether or not they are specifically enumerated herein. Thus, in this context, numerical value A is understood as A ± 5% of A. In this context, numerical value A may be considered to include numerical values ​​that fall within the range of the general standard error for the measurement of the characteristic that numerical value A modifies. In some examples used in the appended claims, numerical value A may deviate by the percentages enumerated above, as long as the amount of deviation from A does not substantially affect the basic and novel characteristics of the invention described in the claims. Furthermore, all ranges include the disclosed maximum and minimum values, as well as any intermediate ranges contained within them, whether or not they are specifically enumerated herein.

Claims

1. Aerosol-generating article, Aerosol generating substrate and A downstream element provided downstream of the aerosol generating substrate and aligned axially with the aerosol generating substrate, wherein the downstream element is A fibrous material comprising multiple regenerated cellulose fibers, wherein the regenerated cellulose fibers are one or more of viscose fibers, modal fibers, lyocell fibers, and viscose rayon fibers, and An aerosol generating article comprising a downstream element comprising a cellulosic filter material, which includes an additive coating applied to a plurality of regenerated cellulose fibers, wherein the additive coating contains at least 5% by weight of exogenous lignin on a dry weight basis.

2. Aerosol-generating article, Aerosol generating substrate and A downstream element provided downstream of the aerosol generating substrate and aligned axially with the aerosol generating substrate, wherein the downstream element is A fibrous material comprising multiple natural fibers, wherein the natural fibers are one or more of the following: flax fibers, hemp fibers, jute fibers, kenaf fibers, ramie fibers, abaca fibers, phormium fibers, sisal fibers, coir fibers, cotton fibers, and kapok fibers; An aerosol generating article comprising a downstream element comprising an additive coating applied to a plurality of natural fibers, wherein the additive coating contains at least 5 weight percent of exogenous lignin on a dry weight basis, and a cellulosic filter material.

3. The aerosol generating article according to claim 1 or 2, wherein the additive coating further comprises at least one polysaccharide.

4. The aerosol generating article according to claim 3, wherein the at least one polysaccharide is selected from hemicellulose, corn starch, potato starch, acetylated starch, and combinations thereof.

5. The aerosol generating article according to claim 3 or 4, wherein the additive coating comprises at least 20 weight percent of the at least one polysaccharide.

6. The aerosol generating article according to any one of claims 3 to 5, wherein the weight ratio of exogenous lignin to polysaccharides in the additive coating is 0.25 to 4 on a dry weight basis.

7. The aerosol generating article according to any one of claims 3 to 6, wherein the weight ratio of the at least one polysaccharide to exogenous lignin in the additive coating is at least 2 on a dry weight basis.

8. The aerosol generating article according to any one of claims 3 to 7, wherein the additive coating further comprises at least one crosslinking agent.

9. The aerosol generating article according to claim 8, wherein the at least one crosslinking agent is selected from acetic anhydride, succinic anhydride, pyridine, triacetin, and combinations thereof.

10. The aerosol generating article according to claim 8 or 9, wherein the additive coating comprises at least 0.1 weight percent of the at least one crosslinking agent on a dry weight basis.

11. The aerosol generating article according to any one of claims 1 to 10, wherein the cellulose-based filter material includes at least 1 weight percent of an additive coating.

12. The aerosol generating article according to claim 11, wherein the cellulose-based filter material includes an additive coating of 1% to 15% by weight.

13. The aerosol generating article according to any one of claims 1 to 12, wherein the downstream element substantially does not contain cellulose acetate.

14. The aerosol generating article according to any one of claims 1 to 13, wherein the downstream element is a mouthpiece filter segment comprising a segment of cellulosic filtration material surrounded by a filter wrapper.

15. A method for producing a cellulose-based filtration material for use in the downstream element of the aerosol generating article described in claim 1, wherein the method is A step of providing multiple regenerated cellulose fibers, wherein the regenerated cellulose fibers are one or more of viscose fibers, modal fibers, lyocell fibers, and viscose rayon fibers. A step of forming an additive-coated solution in water containing at least 5% by weight of exogenous lignin and optionally one or more polysaccharides, on a dry weight basis; The step of applying the additive coating solution to the plurality of regenerated cellulose fibers, A method comprising the steps of drying the coated fibers and optionally curing them.

16. The method according to claim 15, wherein the step of providing the plurality of regenerated cellulose fibers includes forming the plurality of regenerated cellulose fibers in the presence of an additive enhancer.

17. A method for producing a cellulose-based filtration material for use in the downstream element of the aerosol generating article described in claim 2, wherein the method is A process for providing multiple natural fibers, wherein the natural fibers are one or more of the following: flax fibers, hemp fibers, jute fibers, kenaf fibers, ramie fibers, abaca fibers, phormium fibers, sisal fibers, coir fibers, cotton fibers, and kapok fibers. A step of forming an additive-coated solution in water containing at least 5% by weight of exogenous lignin and optionally one or more polysaccharides, on a dry weight basis; A step of applying the additive coating solution to the plurality of natural fibers, A method comprising the steps of drying the coated fibers and optionally curing them.

18. The method according to claim 17, wherein the plurality of natural fibers are mercerized before the step of applying the additive coating solution.

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