AN IMPROVED PROCESS FOR PREPARING SMOKING PRODUCTS OF THE TYPE TO BE HEATED AND NOT BURNT.

The present invention relates to an improved process for the preparation of smoke products of the type to be heated and not burned.

It is known that solid smoke products that are exclusively heated and not burned (known in English as "Heat-not-Burn" products, from which the acronym "HnB" - used below - or even as " heated tobacco products" or only with "heat tobacco") generate, if heated by a special device and subjected to a passage of air due to the aspiration by the consumer, an aerosol that derives from the evaporation of the substances contained in said products and which is formed by gases, vapors and liquid microparticles. In particular, water, propylene glycol and, to have a higher density, glycerol are used to obtain the "smoke" effect. In essence, by vaporizing a mixture of these products, a mist is created at a temperature that is linked to the percentage of each component.

In particular, the aerosol has the purpose of simulating the smoke obtained from the combustion of tobacco and, at the same time, has the function of extracting the nicotine from the tobacco or the active principle from other vegetable substances, such as THC (Delta-9 -tetrahydrocannabinol) or CBD (cannabidiol).

More in detail, the device heats the air bringing it to a temperature ranging from 160°C to 250°C, while the boiling temperature of propylene glycol is 188.2°C, that of glycerol is 290°C , that of nicotine is 247°C, that of THC is 157°C and that of CBD is 160°C-180°C.

Both water and propylene glycol are excellent solvents, each of which is able to effectively dissolve nicotine and sufficiently extracts the THC and the CBD. Appropriately, by passing through the vegetable substance (tobacco, extracts based on THC and/or CBD), from a warm current of air and glycol vapours and water, there are solubilization and stripping effects of both the active ingredients and the aromas contained in the vegetable substance itself.

The characteristics of the aerosol depend mainly on the power applied to the heating coil of the heating device, which determines the temperature of the air passing through the HnB product, from the physical characteristics of the HnB product formulation (for example of viscosity and wettability) and from the specific heat capacity of said formulation. Furthermore, the pressure drops, the air flow rate and the density of the aerosol can vary between and within the heating devices. Currently, HnB solid smoke products are generally made using reconstituted tobacco and/or the inflorescence of the Cannabis plant with the addition of additives aimed at reducing and improving the thermal conductivity of the vegetable product and at the same time reducing the speed of combustion of the same.

As is known, reconstituted tobacco is obtained from tobacco powders to which various substances are added so as to allow the production of:

- a tobacco sheet, obtained by casting from the "slurry" and/or obtained by rolling with a technique corresponding to that of papermaking, and which is then used to obtain cigarettes for use in heating devices;

- tobacco granules, obtained by extrusion, and which are then used in heating devices.

In particular, to obtain the reconstituted tobacco in the two forms described above, dedicated plants are used that have a great environmental impact due to the high consumption of:

- water;

- energy used both to grind tobaccos and to dry powders to which quantities of water and other liquids have been added such that the absolute humidity of the product to be dried can be in the range 50% -85% calculated on a wet basis.

These dedicated plants for the preparation of reconstituted tobacco differ completely from conventional plants, i.e. from the plants used for the production of conventional cigarettes, cigarillos, or cut tobaccos used to prepare the so-called "handmade cigarettes", and/or tobacco products pipe cuts and other products in which tobacco is to be burned.

Moreover, the dedicated plants for the preparation of reconstituted tobacco are extremely expensive, in particular if compared to the aforementioned conventional plants provided for the production of tobacco for use in products/cigarettes in which said tobacco is burned.

In particular, the cut tobacco, which is produced in conventional plants and is therefore intended for the preparation of cigarettes of the type in which tobacco combustion is envisaged, generally has a propylene glycol content of less than 5% calculated on an anhydrous basis and a speed of combustion suitable for the use made of it. In these plants, at the end of the production process, the cut tobacco has an absolute final humidity in the range 12% -18% measured on a wet basis and, after cutting and before final drying, the cut tobacco can have a humidity included in the range 18% -35%.

However, conventional cut tobacco that is intended to be used in smoke products (cigarettes) where it is expected to be burned (also called "lit cigarette"), if used as such in HnB products where there is heating and not combustion, is not able to develop a sufficient aerosol, due to the low content of propylene glycol and/or other additives.

On the other hand, the solution of adding to the tobacco leaf, prior to cutting, additives for retarding combustion is already known and, for this purpose, for example sodium chloride can be used.

Moreover, the addition to the leaf tobacco of propylene glycol and/or glycerol is allowed up to quantities not exceeding 6% by weight of propylene glycol or glycerol since the cutters, currently used in conventional plants, are not able to properly cut/chop additivated tobacco beyond these limits. In particular, it has been noted that adding to the tobacco high quantities (greater than 4-5%) of glycol and glycerol, which also act as lubricating substances, reduces the friction between the tobacco and the means (tracks) that cause the advancement and compacting of the tobacco towards the cutting mouth of the cutter; in this case, in fact, the tobacco slips and advances discontinuously towards the cutting mouths of the cutter, thus obtaining cut pieces of highly variable widths and an undesired high production of waste and dust.

Substantially, currently, the reconstituted tobacco used for the HnB products, and obtained with the aforementioned dedicated plants, is preferred to the cut tobacco (which is obtained with conventional implants and is intended to be used in smoke products in which said tobacco is burned), for at least two characteristics:

- the ability to generate aerosol with a propylene glycol content of more than 10% calculated on an anhydrous basis, and

- low combustion speed.

In this regard, for example, WO 2017/051034 describes a process for the production of reconstituted tobacco for use in devices that heat the tobacco without burning it. The process provides to add a wetting agent, for example glycerol or propylene glycol, in an amount ranging from 1 to 25% on an anhydrous basis of the reconstituted tobacco, to a fraction of water-soluble tobacco (i.e. a fraction comprising all the tobacco components soluble in water). In particular, this tobacco fraction, to which the wetting agent and in particular the propylene glycol is added, is obtained by immersing a tobacco mixture in water and then separating, in particular by mechanical pressing, the soluble fraction from the fibrous fraction. In any case, this process provides for the addition of propylene glycol within the traditional processes for making reconstituted tobacco, that is, in processes of the type used for the manufacture of paper ("papermaking") or of the casting type or of the extrusion type. In particular, in the case of reconstituted tobacco obtained with the same process used for making paper, the propylene glycol is added to the tobacco sheet before cutting the said sheet.

Furthermore, CN 108713788 also describes a process for the production of reconstituted tobacco to be used with cigarettes of the type heat-not-burn (HnB). In particular, this process provides for starting from raw starting materials comprising 50-80% of tobacco, 10-30% of an atomizing agent (which can be glycerol or propylene glycol), 0.5-10% of binder, 0.01 -1 % of a leavening agent, 5-15% of flavoring additives and 0-30% of water. These materials are mixed and then subjected to a rolling process to obtain a tobacco sheet that is then cut. Also, in this case, the atomizing agent is added to the tobacco mixture before its cutting.

Furthermore, US 2006/0021626 describes a filling material for smoke products which has a faster combustion speed, releases a greater quantity of smoke and is resistant to extinction. Therefore, this filling material is used for the preparation of cigarette-type smoking products to be burned, and not of the Fleat- not-Burn (FlnB) type, that is "to be heated and not burned". Furthermore, the wetting agent (for example glycerol or propylene glycol) is added to the tobacco mixture prior to its cutting. In any case, even US 2006/0021626 provides that the filling material be obtained with the traditional processes foreseen for the production of reconstituted tobacco, that is with processes of the type used for the manufacture of the paper ("papermaking") or of the casting type or of the extrusion type.

The object of the present invention is to solve the aforementioned drawbacks present in traditional solutions by proposing a process which, by using cut tobacco and/or the inflorescence of the Cannabis plant, allows to obtain solid cigarette-like smoke products to be heated and not burned (FlnB) with substantially corresponding, or even better, characteristics than those obtained exclusively or mainly with reconstituted tobacco. Another object of the invention is to propose a process which allows to obtain, starting from the cut tobacco, a solid product to smoke which, if heated, does not burn but generates an aerosol.

Another object of the invention is to provide a process that allows energy savings.

Another object of the invention is to provide a process which can be implemented in conventional systems in a simple, rapid manner and with low costs.

Another object of the invention is to provide a process that can be implemented in systems with low manufacturing costs.

Another object of the invention is to provide a process which is ecologically sustainable and, in particular, which allows to reduce energy and water consumption.

Another object of the invention is to provide a process for the preparation of solid products to smoke to be heated and not burned (HnB) which does not require the use of reconstituted/homogenized tobacco and which, therefore, does not require the use of the plants currently planned for the preparation of reconstituted/homogenized tobacco.

Another object of the invention is to provide a process for the preparation of solid smoke products for cigarettes to be heated and not burned (HnB) which avoids the production of a sheet of tobacco to be dried and/or cut by casting or rolling.

Another object of the invention is to propose a process which has an alternative and/or better characterization than the traditional ones.

All these aims, both individually and in any combination thereof, and others which will be apparent from the following description, are achieved, according to the invention, with a process with the characteristics indicated in claim 1 , as well as with a solid smoke product of the type to be heating and not burning (HnB) with the characteristics indicated in claim 40.

The present invention is further clarified hereinafter in some of its preferred embodiments reported for purely exemplifying and non-limiting purposes with reference to the accompanying drawings, in which :

the figure 1 a and 1 b show in a schematic view, respectively, the cigarettes-holder drum and the needle holder provided in a drum apparatus usable in the process according to the invention, the figures 2a and 2b show in a schematic view, respectively, a different variant of the cigarettes-holder drum and needle carrier drum in another apparatus used skilled in the process according to the invention, and

figure 3 shows in a schematic view the coaxiality of the interaction between the cigarette and the needle in the apparatus of fig. 1 a, 1 b or fig. 2a or 2b.

First of all it is specified that all the humidity values identified herein, and presented below, are intended as determined according to the measurement system on a wet basis. In particular, the humidity values are defined as the percentage of water contained in the total mass of the corresponding product and, in other words, it is the percentage ratio between the quantity of water and the total mass of the water and tobacco mixture. Suitably, these values are obtained using the traditional processs provided in the literature for measuring the quantity of water in a product, such as those presented in“Tobacco Moisture, Water and Oven Volatiles - A status report of common moisture processs used within the tobacco industry” By Nils Rose ET AL. in 'Analytical and bioanalytical chemistry" (1 July 2014, pages 1 -16).

The following also specifies that for solids products (articles) to smoke, based on tobacco and/or extracts of the cannabis plant, generating an aerosol and of the "heat-not-burn" type, we mean products in which, for generating an aerosol, the tobacco-based material and/or extracts of the cannabis plant is heated and not burned and in which, in particular, no combustion of said material is foreseen. Preferably, the heat-not-burn product, which generates an aerosol, comprises a tobacco-based material and/or extracts of the cannabis plant which is heated (in particular at a relatively low temperature) in so as to form a vapor (aerosol), but avoiding the ignition and combustion of said material.

In particular, the solid smoke products (articles) according to the invention, for example a cigarette, of the "heat-not-burn" type (i.e. "to heat and not to burn") comprise exclusively tobacco or a tobacco-based material that, unlike traditional cigarettes (i.e. "lit cigarette" type), is not burned.

Appropriately, the "heat-not-burn" solid smoke products include the so- called "electrically heated tobacco products" (known by the acronym "EHTP", i.e. "electrically heated tobacco products") which, based on how much reported in “Verification of the absence of combustion processes in the electrically heated tobacco system, EHTS”, pages 1 -14, 0. Fujita and H. Yan, November 6, 2015, are products in which no ignition occurs, and therefore no burning of tobacco. In particular, these products are heated without reaching the ignition temperature of the tobacco-based material and/or in the absence of live flames, and therefore no combustion occurs.

Advantageously, the process according to the invention is provided specifically and exclusively for the preparation of solid products for smoking, based on tobacco and/or cannabis (i.e. containing tobacco and/or cannabis), of the type to be heated and not burned ("Heat-not-burn").

Preferably, said solid smoke products are of the type of the cigarette to be heated and not burned ("heat-not-burn") and which generate an aerosol.

"Natural tobacco" hereinafter referred to as tobacco without (and therefore to which were not added) additives, binders or the like; appropriately, moreover, "natural tobacco" means tobacco which is not of the "reconstituted" or "homogenized" type.

Advantageously, the process according to the invention comprises the steps of:

- preparation of a mixture of tobacco and/or cannabis; preferably, this preparation is carried out by composing a group (also called "batch") containing various tobacco packages (for example in boxes, bales, etc.) according to the percentage foreseen for each type of tobacco; preferably, the absolute humidity of the tobacco in this phase is about 10% -14%,

- humidification and tanning of the tobacco and/or cannabis mixture, thus prepared, by humidification with water and addition of liquid and solid additives; suitably, the addition of water and additives is regulated according to the weight of the tobacco and, preferably, this phase is carried out in special cylinders; preferably, the absolute humidity of the tobacco in this phase is about 17% -30%,

- mixing and storage in suitable containers (silos) of the mixture of tobacco and/or preserved cannabis,

- discharge and mixing of said mixture of tobacco and/or preserved cannabis,

- cutting of the mixture of tobacco and/or cannabis preserved so as to obtain a cut material, based on tobacco or cannabis; advantageously, the cutting width of the tobacco depends on the final destination of the tobacco itself and, in particular, the finer cut is used for cutting for handmade cigarettes while the wider one is used for pipe cutting,

- drying of the cut material; advantageously, drying can take place in drying cylinders, fluid beds or pneumatic transports; suitably, the drying temperatures are greater than about 100°C; properly, the absolute humidity of the product at the end of this phase is about 12% -16%,

- mixing and storage of cut and dried material;

- preparation (packaging) of a solid product to smoke (cigarette) using the cut material thus prepared; in particular, in this phase, the cut and dried material is wrapped, possibly together with the filter, by the paper cylinder so as to obtain the traditional configuration of a cigarette.

Preferably, the process according to the invention can also comprise, after the step of mixing and storing the cut and dried material, a perfuming step of the product thus prepared in suitable cylinders, appropriately adding liquid additives with an alcoholic and/or aqueous base to improve the aroma of this product. Suitably, the addition of the additives is regulated according to the weight of the tobacco present in the cut and dried material. Advantageously, the perfumed cut material is then mixed and stored before the production/packaging of the solid product to smoke.

Preferably, the packaged solid products for smoking (i.e. cigarettes) can subsequently be packaged in groups and, in particular, in this step, a plurality of products are inserted in a package which is then suitably closed and sealed.

Preferably, the aforementioned steps of the process according to the invention can be implemented with traditional systems, i.e. in those plants used for the production of solid products for smoke in which the tobacco is destined to be subjected to ignition and combustion, such as for example conventional cigarettes , cigarillos, cut tobaccos used to prepare the so-called "handmade cigarettes", and/or pipe cutters.

Preferably, the process according to the invention can be implemented in a traditional plant of the type that is currently used for the products/articles intended to be burned, a plant which is therefore different with respect to the known dedicated systems which are currently provided for obtaining reconstituted/homogenized tobacco . Conveniently, the process according to the invention does not provide any preliminary step of mixing the tobacco powders, obtained by comminuting the solid components of tobacco, with other substances (water, binding agent, a material to form an aerosol) and this in order to form a dough or "slurry" to be poured, laminated or extruded.

Conveniently, the process according to the invention does not provide in any way for making a tobacco sheet and, in particular, does not include a step in which a tobacco sheet is made. More in detail, the process according to the invention does not provide for either forming and casting a dough or "slurry", nor a pressing step by means of rolling cylinders, nor an extrusion step to obtain tobacco granules.

The process according to the invention provides for the propylene glycol to be added to a material, based on tobacco and/or cannabis, which has already been cut in a percentage not less than 6% by weight on an anhydrous basis of the cut material.

Preferably, the process according to the invention provides to add to a material already cut, based on tobacco and/or cannabis, propylene glycol in a percentage equal to about 6-30%, preferably equal to about 10-21 %, by weight on an anhydrous basis of the cut material.

Preferably, said already cut material to which the propylene glycol is added consists exclusively of natural tobacco. Preferably, said already cut material to which the propylene glycol is added does not include reconstituted/homogenized tobacco. Preferably, said already cut material to which the propylene glycol is added can consist of a mixture of natural tobacco and reconstituted/homogenized tobacco. Preferably, the process according to the invention provides to add to a material already cut, based on tobacco and/or cannabis, propylene glycol in a percentage equal to about 10-21 % by weight on an anhydrous basis of the cut material.

Advantageously, the process according to the invention provides to directly add to a material already cut, based on tobacco and/or cannabis, propylene glycol in a percentage equal to about 6-30%, preferably equal to about 10-21 %, in weight on anhydrous basis of the cut material. Preferably, the propylene glycol is applied directly and only to tobacco already cut; properly, this allows to simplify the production process and also to optimize the quantity of glycol that is added. Suitably, the propylene glycol is not added and/or combined with a binder and is not applied to a substrate/carrier other than the cut tobacco. Conveniently, in the process according to the invention the tobacco, to which the propylene glycol is added, is never combined with a binder, neither before nor after its cutting and neither before nor after the addition of propylene glycol. Conveniently, the process according to the invention provides to directly add to a product, which consists only and exclusively of tobacco already cut, propylene glycol in a percentage equal to about 6-30%, preferably equal to about 10-21 %, by weight on anhydrous base of the cut material.

Advantageously, the process according to the invention provides to add directly to a material, which consists only and exclusively of tobacco already cut/cut into strips (for example of the type known as "cut rag tobacco") from a cutter, propylene glycol in percentage equal to about 6-30%, preferably equal to about 10- 21 %, by weight on an anhydrous basis of the cut material.

Conveniently, the process according to the invention provides to add, as a substance/agent for the formation of an aerosol, only and exclusively propylene glycol in a percentage equal to about 6-30%, preferably equal to about 10-21 %, by weight on anhydrous base of the cut material.

Conveniently, the process according to the invention provides to add, as a substance/agent for the formation of an aerosol:

- propylene glycol in a percentage equal to about 6-30%, preferably equal to about 10-21 %, by weight on an anhydrous basis of the cut material, and likewise

- glycerol, or another substance, in a percentage - defined by weight on an anhydrous basis of the cut material - which is lower than that of propylene glycol.

Conveniently, the process according to the invention provides to add at least one substance/agent for the formation of an aerosol directly on the tobacco, already cut/cut into strips, which:

- consists only of propylene glycol in a percentage equal to about 6-30%, preferably equal to about 10-21 %, by weight on an anhydrous basis of the cut material, or

- consists of propylene glycol in a percentage equal to about 6-30%, preferably equal to about 10-21 %, by weight on an anhydrous basis of the cut material and also of glycerol in a percentage - always defined by weight on an anhydrous basis of the cut material - which is lower than that of propylene glycol. In particular, advantageously, the propylene glycol is preferable with respect to other substances/agents which allow the formation of an aerosol in that it has a boiling point (of about 188°C) which is lower than that of the nicotine (which is of about 247°C), thus allowing the generation of a suitable aerosol without thereby removing the most aromatic and volatile substances of the tobacco, in particular extracting a more precise quantity of nicotine, and without causing its denaturation. On the contrary, for example, the glycerol has a boiling temperature of about 290°C which - being higher than the boiling temperature of the nicotine (of about 247°C) - requires heating the tobacco to an excessive temperature, and therefore to a uncontrolled extraction of nicotine. Furthermore, advantageously, the use of propylene glycol allows, during use, to heat the tobacco-based material at lower temperatures, thus limiting the energy consumption of the device with which the smoke product containing said tobacco-based material is heated in order to generate the aerosol.

Advantageously, the process also provides for adding glycerol to a cut tobacco or cannabis-based material.

Conveniently, in the process according to the invention, the glycerol, if provided, is added to the already cut tobacco in a lower percentage quantity than the propylene glycol.

Preferably, in any case, the addition of propylene glycol and/or glycerol is carried out on the already cut tobacco and/or cannabis-based material. Suitably, in this way it is possible to precisely control the amount of propylene glycol and/or glycerol used.

Advantageously, the process also provides for adding additives to the cut tobacco or cannabis-based material. Preferably, said additives include combustion retarding additives, such as for example sodium chloride. Suitably, the additives can be chosen to customize the product or to modify its organoleptic characteristics.

Preferably, in the process according to the invention the propylene glycol, the glycerol and the possible additives are the only substances to be added to the cut tobacco. In particular, for example, no binding substances are added, such as for example cellulose fibers, hydroxypropyl cellulose, hydroxypropyl methylcellulose, hydroxyethylcellulose, microcrystalline cellulose, methylcellulose, carboxymethylcellulose (CMC), corn starch, potato starch, guar gum, carobs seed, pectins (for example tobacco pectins) and alginate compounds (for example ammonium alginate and sodium alginate).

Advantageously, the process according to the invention - which is provided specifically and exclusively for the preparation of solid smoke products, of the type to be heated and not burned ("heat-not-burn") - comprises the following phases in which:

- tobacco leaves of at least one type are made available,

- the leaves are humidified, preferably by wetting with/in water, the tobacco leaves previously mixed,

- the tobacco leaves made available are mixed, preferably mechanically,

- the moistened tobacco leaves are cut to obtain cut tobacco,

- to the so obtained cut tobacco is added propylene glycol in a percentage equal to about 6-30%, preferably equal to about 10-21 %, by weight on an anhydrous basis of the cut tobacco.

Suitably, the process also comprises a step in which the cut tobacco is dried.

Conveniently, the process also comprises a step in which the cut and dried tobacco is packaged with a coating/packaging material, so as to obtain a solid product to smoke of the type to be heated and not to smoke (i.e. of the "heat not burn" type - "HNB").

Conveniently, the process also comprises a step in which a plurality of solid smoke products of the type to be heated and not burned (i.e. of the "heat not burn" type, "HnB") are packaged, each of which is obtained by packaging the cut tobacco with a coating/packaging material.

Preferably, the process according to the invention provides to add to the cut tobacco propylene glycol in a percentage equal to about 6-30%, preferably equal to about 10-21 %, by weight on an anhydrous basis of the cut tobacco, immediately after cutting.

Preferably, the process according to the invention provides to add to the cut tobacco propylene glycol in a percentage equal to about 6-30%, preferably equal to about 10-21 %, by weight on an anhydrous basis of the cut tobacco, immediately before and/or during and/or immediately after drying the cut tobacco. Preferably, the process according to the invention provides to add to the cut tobacco propylene glycol in a percentage equal to about 6-30%, preferably equal to about 10-21 %, by weight on an anhydrous basis of the cut tobacco, immediately before and/or during and/or immediately after the packaging of said cut tobacco to form a solid product to smoke of the type to be heated and not burned (i.e. of the "heat not burn" type, "HnB").

Preferably, the process according to the invention provides to add to the cut tobacco propylene glycol in a percentage equal to about 6-30%, preferably equal to about 10-21 %, by weight on an anhydrous basis of the cut tobacco, immediately before and/or during and/or immediately after the packaging of a plurality of solid smoke products, of the type to be heated and not burned (i.e. of the "heat not burn" type, "HnB"), and obtained by packaging said cut tobacco.

Substantially, suitably, the process according to the invention provides to add - in one or more of the successive phases with respect to those in which the cut material is obtained - propylene glycol in a percentage equal to about 6-30%, preferably equal to about 10 -21 %, by weight on anhydrous basis of the cut material.

Preferably, the process according to the invention - which is specifically and exclusively provided for the preparation of solid smoke products, of the type to be heated and not burned ("heat-not-burn") - comprises the following phases in which:

- leaf flaps of at least one type of tobacco are made available on a processing line and, separately, tobacco ribs are made available on another processing line; appropriately, for this purpose, the tobacco leaves are previously treated - generally in a plant and/or dedicated line/area - so as to separate the leaf edges from the ribs,

- the leaf edges and the ribs are wetted, preferably by wetting with water, on the respective/separate processing lines,

- the leaf edges and ribs made available on the respective/separate processing lines are mixed, preferably mechanically,

- the leaflets of moistened tobacco and the moistened tobacco ribs are cut, always on the respective/separate processing lines, to obtain leaf flaps of cut tobacco and cut tobacco ribs,

- to the leaf flaps of cut tobacco and/or to the cut tobacco ribs previously obtained propylene glycol is added in a percentage equal to about 6-30%, preferably equal to about 10-21 %, by weight on an anhydrous basis of the respective product.

Appropriately, during and/or after said humidification step but before said cutting step, the leaf edges and/or the tobacco ribs can be added propylene glycol and/or glycerol or sorbitol in a percentage lower than about 5% on an anhydrous basis of said tobacco leaves.

Suitably, the process also comprises a step in which the cut leaf flaps and cut tobacco ribs are dried, preferably on the respective/separate processing lines. Conveniently, after drying and before packaging the solid product for smoking, preferably before perfuming, the cut and dried leaf flaps (obtained in a first processing line) are joined/mixed with the cut and dried tobacco ribs (obtained in another processing line).

Advantageously, said cut material, based on tobacco or cannabis, is of the type used for the production of solid products for smoking in which the tobacco is destined to be burned, such as for example conventional cigarettes (i.e. of the type to be burnt, so called also "lit cigarettes", cigarillos, tobaccos used to prepare the so-called "handmade cigarettes" and/or pipe cutters.

In particular, the cut material, based on tobacco and/or cannabis, is formed from pieces that are obtained, starting from a humidified and stored tobacco and/or cannabis mixture, through width cuts ("width of cut") substantially in the range of 0.12-2.5 mm. Suitably, the cut material comprises exclusively or mainly pieces, comprising a mixture of tobacco and/or cannabis, of a width of about 0.12-2.5 mm. Suitably, the cut material is formed from pieces of tobacco that are obtained from a mixture of tobacco of the same type or even of different types.

Advantageously, the process according to the invention provides for the addition of propylene glycol, glycerol and/or other additives to a cut material which consists of a mixture of cut tobacco, preferably of various types of tobacco, which is obtained by mechanical mixing.

Advantageously, the process according to the invention provides for the addition of propylene glycol, glycerol and/or other additives to the cut material - in particular to cut tobacco - as in this there is a greater probability, compared to one kilogram of flaps leaves (strips), to find all the components of the different types of tobacco initially used for the formation of the mixture. Advantageously, in the process according to the invention, the propylene glycol and/or the glycerol and/or the other additives are added, in the liquid state, completely or partially in one or more of the following passages:

- immediately after the cutting phase of the tobacco and/or cannabis mixture, and/or

- after the drying phase and/or after the fragrance phase of the cut material, and/or

- during the packaging phase (production) of solid smoke products (cigarettes) containing the cut material, and/or

- after the packaging (production) phase of solid smoke products (cigarettes) containing the cut material,

- during the packaging phase of solid smoke products (cigarettes) containing the cut material.

Conveniently, in the process according to the invention, the addition of propylene glycol and/or glycerol and/or the other additives can be carried out in only one of the aforementioned passages so as to substantially reach in a single passage a percentage of propylene glycol equal to about 6-30%, preferably equal to about 10-21 %, by weight on an anhydrous basis of the cut material.

Conveniently, in the process according to the invention, the addition of propylene glycol and/or glycerol and/or the other additives can be carried out partially in two or more of the aforementioned steps (or even in all five) so that the final and overall percentage of propylene glycol of the cut material present in the smoke solid product thus obtained is equal to about 10-21 % by weight based on the anhydrous base of the cut material.

Advantageously, in the process according to the invention, the propylene glycol and/or the glycerol and/or other additives can be partially added to the liquid state before cutting the tobacco and/or cannabis-based material, preferably during the humidification step. However, it is understood that the addition of propylene glycol to the tobacco before its cutting, preferably during the humidification step, is carried out so that it is equal to or less than about 5% by weight on the anhydrous basis of the tobacco itself.

Suitably, the process according to the invention may provide that:

- before its cutting, the tobacco is not added (and therefore appears to be devoid of) propylene glycol, - after the cutting of said tobacco, a percentage of propylene glycol not less than 6% by weight on anhydrous basis of the cut tobacco is added to the tobacco itself.

Suitably, the process according to the invention may provide that:

- before the cutting of the tobacco, it is added to the tobacco itself, preferably humidified, a percentage of less than 5% propylene glycol by weight on an anhydrous basis of said tobacco,

- after cutting of said tobacco - to which, before cutting, a percentage of propylene glycol less than 5% by weight on anhydrous anhydrous basis of the cut material had already been added - a percentage of propylene glycol not less than 6% by weight on anhydrous basis of the cut tobacco is added.

Conveniently, the process according to the invention provides that, prior to the cutting of the tobacco, a percentage of glycerol less than 5% by weight on anhydrous base of said tobacco to be cut is added to the tobacco itself, preferably humidified.

Advantageously, the process according to the invention provides that, before the tobacco is cut, sorbitol is added to the tobacco itself, preferably humidified.

Conveniently, the process according to the invention provides that, before the tobacco is cut, only water is added to the tobacco itself.

Conveniently, the process according to the invention provides that, prior to the cutting of the tobacco, only propylene glycol and/or glycerol and/or sorbitol in a percentage of less than 5% by weight on anhydrous base of said tobacco is added to the tobacco itself.

Advantageously, in the process according to the invention, the propylene glycol and/or the glycerol and/or the other additives are added in the liquid state - entirely or partially - immediately after the tobacco cutting step, preferably when the absolute humidity of the cut material is in the OV range of 16% -38%. Conveniently, in this case, the propylene glycol is added in an amount equal to 3% -30% of the anhydrous weight of the cut tobacco to be treated and, preferably, in a quantity equal to 6% -22% of the anhydrous weight of the cut tobacco to be treated.

Advantageously, in the process according to the invention, the propylene glycol and/or the glycerol and/or the other additives can be added - entirely or partially - immediately after the drying step or after the perfuming step, preferably when the absolute humidity of cut is 10% -18%. Conveniently, in this case, the propylene glycol is added in an amount equal to 3% -30% of the anhydrous weight of the cut material to be treated and, preferably, in a quantity equal to 6% -22% of the anhydrous weight of the cut one to be treated.

Advantageously, in order to add propylene glycol and/or glycerol and/or the other cut additives, the latter is laid on a belt conveyor having an adjustable feed speed. Conveniently, by changing the speed of the conveyor belt, with the same deposition rate of the cut material on the conveyor belt and of the width of the belt itself, the thickness of the layer of cut material which forms on said conveyor belt is modified. Advantageously, in this way the use of a cylinder similar to that used for the application of tanning or perfuming is avoided which, due to the difference in speed existing between the peripheral speed of the cylinder and that of the cut conveyed, would lead to the undesired formation of tobacco balls.

Advantageously, above the conveyor belt devices are provided for spraying one or more substances in the liquid state onto the layer of cut material deposited on the belt itself. Advantageously, the liquid substance which is added, preferably by spraying and/or nebulising, on the cut material deposited on the conveyor belt comprises propylene glycol. Preferably, the liquid substance which is added, preferably by spraying and/or nebulising, on the cut material deposited on the conveyor belt comprises propylene glycol mixed with water and/or other additives which are used to improve the final qualities of the product.

Preferably, the spraying devices comprise spray nozzles having an adjustable flow rate so as to be able to easily adapt the spray system to the quantity of liquid to be added.

Advantageously, in order to improve the uniformity of the treatment, the operation of depositing the cut material on the conveyor belt and adding by spraying and/or nebulizing propylene glycol, glycerol and/or other additives can be repeated one or more times. Preferably, the cut material is deposited by a first conveyor belt to a subsequent adjacent one which may have the same or opposite direction of advancement with respect to the first.

Advantageously, the liquid substance which is added, preferably by spraying and/or nebulising, on the cut material deposited on the conveyor belt can also comprise water. Appropriately, water is used to improve the absorption of liquids by the cut material. Suitably, after cutting, the cut material is then subjected to drying. Preferably, in particular in the case in which water is added to the cut material, the latter is then subjected to a drying step. Advantageously, drying is carried out in a convection and/or conduction dryer in which the temperature of the heating fluid and of the contact walls is 30°C-130°C, preferably 50°C-90°C.

Conveniently, in the process according to the invention the drying step is carried out at lower temperatures than those provided in the state of the art, thus allowing to avoid the removal of the most aromatic and volatile substances of tobacco. This is advantageous in that it allows to avoid the evaporation of the propylene glycol, and therefore to keep its quantity substantially unchanged within the cut material to be used later in the solid smoke products. On the contrary, in the case of drying at temperatures above 130°C, as envisaged in the state of the art, in addition to and/or instead of the propylene glycol which evaporates at the above temperatures, the use of glycerol and/or additional aerosol-forming substances/agents that can withstand drying temperatures above 130°C is needed.

Advantageously, in the process according to the invention, the propylene glycol and/or the glycerol and/or the other additives can be added - entirely or partially - during and/or after the step of packaging the cut material so as to obtain a solid product for smoke of the type "to be heated and not burned” (i.e. " heat-not- burn","HnB"), preferably cigarettes with or without a filter.

Appropriately, the solid product to smoke to be heated and not burned (that is of the "heat-not-burn" type, "HnB"), in particular a cigarette, is packaged by wrapping the cut material, based on tobacco and/or cannabis, with an external covering/packaging material - preferably defined by a paper cylinder - which wraps and contains said cut material.

Advantageously, said external covering/packaging material may comprise paper with a low combustion speed and/or may contain, at its inner surface, substances which prevent combustion and which, at the same time, prevent the flow of air between the external and internal surface of said external covering/packaging material.

The solid product from cigarette smoke can be:

- without filter, when it includes only the external covering/packaging material (ie the paper cylinder) and the cut material to be heated, based on tobacco and/or cannabis, which is contained within it; - with filter, when a cylindrical element of filtering material is also applied to one end.

Conveniently, by packaging step is meant the step in which the cut material to be heated based on tobacco and/or cannabis is wrapped, possibly together with the filter, by the external covering/packaging material (i.e. the paper cylinder) in order to obtain the smoke product, that is the cigarette itself.

Advantageously, to add the liquid containing propylene glycol and/or glycerol and/or the other additives during and/or after packaging the solid smoke product, i.e. the cigarette, of the type "to be heated and not burned” ("HnB") it can be use a first type of liquid dosage apparatus, preferably of the traditional type.

Advantageously, this first type of liquid dosage apparatus comprises application means, for example injection needles or spray nozzles/nebulizers, for applying the aforementioned liquid to the cut material present in the cigarette to be packaged/packaged.

Conveniently, the amount of the aforementioned liquid to be added depends on the weight of the cut material to be heated, based on tobacco and/or cannabis, present in the cigarette already packaged/to be packaged. In particular, considering that the weight of the cut material to be heated is equal to or less than about 500 mg, suitably, the liquid to be added (containing propylene glycol and/or glycerol and/or other additives) is substantially included in the range 4% -20% of the anhydrous weight of the cut material to be heated and, in particular, is about 20mg- 100mg.

Suitably, as shown in fig. 1 a, this first liquid dispensing apparatus comprises a rotating needle-carrying drum 3 which, preferably, comprises a series of needles 4 for injecting liquids, needles which are mounted on said rotating drum.

The cigarette packaging machine comprises a corresponding rotating cigarette-holding drum 5 with a plurality of cavities 6 provided on the lateral surface of the drum itself and each containing a cigarette 7 during packaging or already packaged (see Fig. 1 b). Conveniently, each cigarette 7 is held within the respective cavity 6 by a pneumatic system.

Conveniently, the rotating needle-holding drum 3 of the liquid dispensing apparatus is positioned facing the rotating cigarette-holding drum 5 of the packaging machine so that each injection needle 4 is axially facing a cigarette 7 (see fig. 3). Advantageously, the needle-carrying drum 3 is coaxial with the cigarette-holding drum 5 and, moreover, each needle 4 of the first is coaxial with a corresponding cigarette 7 housed in the second one. Advantageously, the two drums 3, 5 have the same rotation speed.

Appropriately, therefore, during and/or after the packaging (production) phase of the cigarettes, each needle 4 of the dosage apparatus injects a corresponding quantity of predefined liquid into the facing cigarette 7 during packaging or the already packaged cigarette.

Conveniently, in the embodiment shown in figs. 1 a and 3, described above, the application means comprise a series of needles 4, preferably coaxial with the cigarettes 7 which they face, configured to be able to penetrate inside the cigarette 7 and inject the predefined quantity of liquid directly inside the cigarette itself.

In another embodiment, not shown, the application means can comprise nozzles configured to spray/atomize the liquid onto the cut material of the cigarette 7, preferably from a close distance.

Advantageously, the propylene glycol, glycerol and/or other additives can be added by direct application, as described above, and/or can be added indirectly by the introduction/insertion into the cigarette - at the tobacco and/or cannabis based cut material - of capsules containing, in the liquid state, propylene glycol, glycerol and/or other additives. Conveniently, these capsules - inserted into the cut material contained in the cigarette already packaged or to be packaged - are intended to be opened and/or broken as a result of their compression, thus allowing the propylene glycol, glycerol and/or other additives contained within the same capsules to impregnate the cut tobacco material of the cigarette. Conveniently, this technology of introduction/insertion by means of capsules corresponds to that already used for inserting the capsules for aromatizing the smoke inside the cigarette filters, with the difference however that in this case the capsule is inserted inside and at the cut tobacco and/or cannabis based material.

Advantageously, in the process according to the invention, the propylene glycol, the glycerol and/or the other additives can be added - entirely or partially - during the packaging step of the smoke products, in particular of the cigarette type, of the type to be heated and do not burn ("HnB").

Advantageously, in order to add the liquid containing propylene glycol and/or glycerol and/or the other additives during the step of packing the cigarettes, a second type of liquid dosage apparatus, preferably of the traditional type, can be used.

Advantageously, this second type of liquid dispensing apparatus comprises application means, for example injection needles or spray nozzles/nebulizers, for applying the aforementioned liquid to the cut material present in the cigarette to be packaged/packaged.

Suitably, as shown in fig. 2a, this liquid dispensing apparatus comprises a rotating needle-carrying drum 10 which, preferably, comprises a series of needles 11 for injecting liquids. In particular, the needles 11 are subdivided into a series of groups 12 which are suitably mounted on said rotating drum.

The cigarette packing machine comprises a corresponding rotating cigarette-holding drum 13 with a plurality of molds 14 provided on the side surface of the drum and each containing a predetermined number of cigarettes 15 to be packed. Conveniently, the position of each cigarette 15 inside the tile 14 is fixed and predetermined.

Conveniently, the rotating needle-holding drum 10 of the liquid dispensing apparatus is positioned and facing the rotating cigarette-holding drum 13 of the packaging machine so that each injection needle 11 is axially facing a cigarette 15 (see fig. 3). Advantageously, the needle-carrying drum 10 is coaxial with the cigarette-holding drum 13 and, moreover, each needle 11 of the former is coaxial with a corresponding cigarette 15 housed in a tile 14 of the latter.

Conveniently, therefore, during the packaging step, each needle 11 of the measuring apparatus injects a corresponding quantity of predefined liquid into the facing cigarette 15, in particular on the cut material present inside the cigarette. Advantageously, the two drums 10 and 13 have the same rotation speed.

Conveniently, in the embodiment shown in figs. 2a and 3, described above, the application means comprise a series of needles 11 , which are preferably coaxial with the cigarettes 15 to which they face, and which are configured to be able to penetrate inside the cigarette 15 and inject the predefined quantity of liquid directly inside the cigarette itself.

In another embodiment, not shown, the application means can comprise nozzles configured to spray/nebulise the liquid on the cut material of each cigarette 15, preferably from a close distance. Conveniently, the present invention also relates to a smoke product to be heated and not burned (i.e. "heat-not-burn" or "HnB"), preferably of the cigarette type and/or rod-shaped, comprising at least one portion for generating an aerosol which is wound inside an external coating/packaging material and which comprises cut tobacco to which, after cutting, propylene glycol was added in a percentage of about 6-30%, preferably equal to about 10-21 %, by weight on anhydrous basis of the cut tobacco.

Conveniently, said smoking product/article is constituted exclusively and solely by said portion to generate an aerosol.

Advantageously, said smoking product/article also comprises an end portion configured to be positioned in the mouth. Advantageously, said end portion configured to be positioned in the mouth comprises a filter, preferably a cylindrical element of filtering material.

Preferably, said portion to generate an aerosol contains exclusively cut tobacco to which, after cutting, propylene glycol was added in a percentage equal to about 6-30%, preferably equal to about 10-21 %, by weight on anhydrous basis of tobacco cut.

Preferably, said portion to generate an aerosol contains exclusively cut tobacco to which, after cutting, it has been added:

- propylene glycol in a percentage equal to about 6-30%, preferably equal to about

10-21 %, by weight on an anhydrous basis of the cut tobacco, and

- glycerol in a lower percentage than propylene glycol.

Advantageously, said portion to generate an aerosol does not contain ligands - such as for example alginates, hydroxypropylcellulose, hydroxypropyl methylcellulose, hydroxyethylcellulose, microcrystalline cellulose, methylcellulose, carboxymethylcellulose (CMC), corn starch, potato starch, guar gum, carob seed flour , pectins and alginates (for example ammonium alginate and sodium alginate

- which have been added to the already cut tobacco. Conveniently, said already cut tobacco does not contain the aforesaid binders in its interior. Preferably, said portion to generate an aerosol does not include cellulose addition to said already cut tobacco Preferably, said cut tobacco does not contain cellulose

Conveniently, said portion to generate an aerosol can also comprise, in addition to said cut tobacco, reconstituted/homogenized tobacco which is also cut. Advantageously, said already cut tobacco is obtained from a mixing, preferably mechanical, of only natural tobacco, of the same type or of different types.

Advantageously, said already cut tobacco is obtained starting from a mixing of humidified leaf flaps, preferably with a humidity of about 17% -30%.

Advantageously, said already cut tobacco is obtained from a mixing, preferably mechanical, of natural tobacco (of the same type or of different types) with reconstituted/homogenized tobacco.

Advantageously, said portion for generating an aerosol can be immediately adjacent to said end portion configured to be positioned in the mouth.

Advantageously, said smoke product to be heated and not burned (i.e. "heat-not-burn" or "HnB"), preferably of the cigarette type, consists exclusively of said extremal portion configured to be positioned in the mouth and from said portion to generate an aerosol.

Advantageously, said smoke product/article to be heated and not burned (i.e. "heat-not-burn" or "HnB"), preferably of the cigarette type, comprises a portion for heat generation or a combustible element which is configured to burn during use in order to generate heat to heat the portion to generate an aerosol. Conveniently, said portion for generating heat or said fuel element is physically separated/distinct from said portion to generate an aerosol. Conveniently, said portion for generating heat or said fuel element is positioned with respect to said portion to generate an aerosol so as to allow heat transfer by conduction and/or convection.

Advantageously, said smoking product/article to be heated and not burned (i.e. "heat-not-burn" or "HnB"), preferably of the cigarette type, can be coupled and/or associated and/or inserted into a configured heating device to allow heating of the portion configured for the generation of an aerosol. Preferably the heating device is not configured to cause combustion of the portion configured for the generation of an aerosol. Preferably the heating device is separate and different from said smoke product/article. Appropriately in this way it is possible to reduce the drying of the tobacco-based product, and therefore preserve its aromas.

None of the prior documents WO 2017/051034, CN 108713788 and US 2006/0021626 teaches to add to tobacco that has already been cut propylene glycol not less than 6% by weight on an anhydrous base of the cut tobacco.

In particular, WO 2017/051034 teaches to add propylene glycol to a soluble aqueous fraction which, after being concentrated, is then added to a sheet of tobacco fibers (in particular reconstituted tobacco) and it is then the sheet thus obtained that is cut. Therefore, in WO 2017/051034 the propylene glycol is added before cutting the reconstituted tobacco sheet and not over the already cut tobacco.

CN 108713788 teaches how to mix powdered tobacco with propylene glycol, binder, raising agent, flavoring additives and water to obtain a mixture; the mixture thus obtained is subjected to a rolling process to obtain a tobacco sheet which is then cut. Therefore, in CN 108713788, propylene glycol is added before cutting the tobacco sheet and not over the already cut tobacco.

US 2006/0021626 teaches to mix together cellulose, tobacco, a binder and a wetting agent (for example propylene glycol) and thus obtain a mixture; with the mixture thus obtained a sheet of tobacco is then obtained which is then cut. Therefore, in US 2006/0021626, propylene glycol is added before cutting the tobacco sheet and not on the already cut tobacco.

Moreover, all the previous documents WO 2017/051034, CN 108713788 and US 2006/0021626 teach to use exclusively reconstituted tobacco, and in particular a reconstituted tobacco sheet, for the preparation of solid cigarette smoking products to be heated and not burned ("HNB"). On the contrary, the process according to the invention provides for the use of traditional cut tobacco of the traditional type, and not only reconstituted tobacco, for the preparation of solid smoke products for cigarettes to be heated and not burned ("HnB").

Moreover, the process according to the invention teaches to select, among the various agents/substances for the formation of aerosols, specifically propylene glycol (to be so preferred with respect to glycerol or other materials for the formation of aerosols), and also provides for selection of a specific quantity, i.e. at least 6% and, preferably 10-21 %, of propylene glycol to be added after the tobacco has already been cut. In particular, the specific selection of propylene glycol is advantageous in that, having a lower boiling point than glycerol, it allows - during use - to provide less heating energy in order to cause its evaporation, and thus generate an aerosol. Moreover, advantageously, by adding the propylene glycol to the already cut tobacco but before its drying, it allows the use of traditional cutting machines (since the glycol is added after this cutting step).

From the aforegoing it is clear that the process according to the invention is particularly advantageous since the chemical-physical and organoleptic characteristics of the final smoke product (cigarette) to be heated and not burnt (HnB), thus obtained, are very similar to those of the other products to be heated and not burned (HnB) which are obtained using exclusively reconstituted tobacco, however the process according to the invention is ecologically more sustainable and, moreover, the costs are considerably lower and, in particular, are reduced: - plant construction and maintenance costs,

- the energy cost used to obtain one kilogram of final product, and

- the costs of additives that are added to traditional solutions both for the formation of the sheet and to obtain the extrusion.

In particular, the final product obtained with the process according to the invention, when heated and not burned, generates an aerosol of gases and vapors containing inhalable tobacco products while preserving as much as possible the taste, the sensory experience, the delivery profile of the nicotine and the traditional characteristics of the smoke products in which the ignition/combustion of the tobacco is expected (i.e. "lit cigarettes").