This invention relates to a method of manufacturing a lyocell material for a cigarette filter, including (S1) spinning a lyocell spinning dope composed of 8 to 13 wt % of a cellulose pulp and 87 to 92 wt % of an N-methylmorpholine-N-oxide (NMMO) aqueous solution; (S2) coagulating the lyocell spinning dope spun in (S1), thus obtaining a lyocell multifilament; (S3) water-washing the lyocell multifilament obtained in (S2); (S4) oiling the lyocell multifilament water-washed in (S3); and (S5) applying steam and pressure to the lyocell multifilament obtained in (S4), thus obtaining a crimped tow having 30 to 40 crimps per inch.

An aerosol-generating article is provided, including: an aerosol-generating substrate; and a filter in axial alignment with the aerosol-generating substrate, the filter including at least one filter segment of filtration material formed of a plurality of fibres including a polyhydroxyalkanoate compound, in which the fibres have a denier per filament (dpf) of between 1.5 dpf and 2.7 dpf, in which a total denier of the fibres is between 25,000 and 40,000, and in which the at least one filter segment includes at least 20 percent by weight of the polyhydroxyalkanoate compound. A filter for an aerosol-generating article is also provided.

An aerosol-generating article is provided, including: an aerosol-generating substrate; and a filter in axial alignment with the aerosol-generating substrate, the filter including at least one filter segment of filtration material formed of a plurality of fibres including a polyhydroxyalkanoate compound, in which the fibres have a denier per filament (dpf) of between 5.0 dpf and 12.0 dpf, in which the filter segment includes at least 20 percent by weight of the polyhydroxyalkanoate compound, and in which a resistance to draw (RTD) of the filter segment is between 10 millimetres H.sub.2O and 25 millimetres H.sub.2O. A filter for an aerosol-generating article is also provided.

An aerosol-generating article is provided for producing an inhalable aerosol upon heating, the aerosol-generating article including: a rod of aerosol-generating substrate, the aerosol-generating substrate including at least 12 percent by weight of an aerosol former, and the rod having a length of from 5 millimetres to 50 millimetres; and a hollow tube segment with a support element and including fibrous filtration material, the hollow tube segment disposed immediately downstream of the rod and in longitudinal alignment with the rod, in which the fibrous filtration material includes fibres including a polyhydroxyalkanoate (PHA) polymer or copolymer, and in which the hollow tube segment includes at least about 25 percent by weight of the PHA polymer or copolymer. A system including an aerosol-generating device and the aerosol-generating article is also provided.

The invention relates to a filter material for a smoking product, comprising a nonwoven material, wherein the nonwoven material is hydro-entangled, the hydro-entangled nonwoven material contains min. 50% and max. 90% wood cellulose fibres, min. 10% and max. 50% fibres from regenerated cellulose and less than 30% non-natural polymers, in relation to the mass of the hydro-entangled nonwoven material, and together the amount of wood cellulose fibres and fibres from regenerated cellulose make up at least 70% of the mass of the hydro-entangled nonwoven material, and the hydro-entangled nonwoven material has a density of min 100 kg/m.sup.3 and max. 300 kg/m.sup.3 and a thickness of min. 100 μm and max. 1000 μm. The invention also relates to a segment with the filter material, a smoking product and a production method.

An aerosol-generating article is provided for producing an inhalable aerosol upon heating, the aerosol-generating article including: a rod of aerosol-generating substrate, the aerosol-generating substrate including at least 10 percent by weight of an aerosol former; and a filter segment formed of fibrous filtration material, the filter segment arranged in longitudinal alignment with the rod, in which the filter segment includes at least about 85 percent by weight based on a total weight of fibrous filtration material of a polyhydroxyalkanoate (PHA) polymer or copolymer, in which a resistance to draw (RTD) of the filter segment is between about 35 millimetres H.sub.2O and about 55 millimetres H.sub.2O, and in which a length of the filter segment is from about 4 millimetres to about 27 millimetres. A filter for an aerosol-generating article is also provided.

An aerosol-generating article is provided, including: an aerosol-generating substrate; and a filter in axial alignment with the aerosol-generating substrate, the filter including at least one filter segment of filtration material formed of a plurality of fibres including a polyhydroxyalkanoate compound, in which the fibres provide a total external surface area within the filter segment of between 0.12 square metres per gram and 0.28 square metres per gram, and in which the at least one filter segment includes at least 20 percent by weight of the polyhydroxyalkanoate compound. A filter for an aerosol-generating article is also provided.

An object of the present invention is to provide a cellulose acetate composition for thermoforming with excellent biodegradability and excellent thermoformability. A cellulose acetate composition for thermoforming containing a cellulose acetate and a glycerin ester-based plasticizer, wherein the cellulose acetate has a degree of acetyl substitution of 1.4 or greater and 2.0 or less, a compositional distribution index (CDI) of 4.0 or less, and a total sulfur content of 15 mg/kg or greater and less than 150 mg/kg.

A filter for a smoking article has improved biodegradability and improved taste during smoking of the smoking article. The filter includes a segment having a filtration substrate including natural cellulose fibres, and a wrapper at least partly surrounding the segment. The filtration substrate contains a composition including an additive for reducing phenols.

A process for producing a filter element suitable for use in smoking articles may include: embedding a bundle of cellulose acetate fibers with an aqueous suspension of polyhydroxyalkanoate (PHA) to obtain a wet bundle of the cellulose acetate fibers covered by the aqueous suspension of the PHA; shaping the wet bundle in a form of a continuous elongated element; heating the continuous elongated element to temperature greater than or equal to 140° C. and less than or equal to 180° C. for time sufficient to melt the PHA and to evaporate water from the continuous elongated element; cooling the heated continuous elongated element to obtain crystallization of the PHA; and cutting the so-obtained continuous elongated element into segments of predetermined length.