CN112384083A

CN112384083A - Improved process for the preparation of smoking products of the heated but not combustible type

Info

Publication number: CN112384083A
Application number: CN201980041817.4A
Authority: CN
Inventors: G·马塔拉佐
Original assignee: Magg Consulting SRL
Current assignee: Magg Consulting SRL
Priority date: 2018-11-23
Filing date: 2019-11-20
Publication date: 2021-02-19
Also published as: EP3883397A1; IT201800010532A1; WO2020104964A1; US20220287357A1; CA3117438A1

Abstract

An improved process for the preparation of smoking products of the heated but not combustible type, in particular in the form of cigarettes, characterized in that to tobacco and/or hemp-based cut material is added propylene glycol in a percentage not less than 6% by weight on a water-free basis of the cut material.

Description

Improved process for the preparation of smoking products of the heated but not combustible type

The present invention relates to an improved process for the preparation of smoking products of the heated but non-combustible type.

It is known that solid smoking products that are heated only but not combusted ("heat-not-burn" products, hereinafter abbreviated to "HnB", or referred to as "heated tobacco products" or "heated tobacco only"), when heated by a particular device and passed through by air as a result of the inhalation of the user, generate an aerosol (aerosol) that originates from the evaporation of the substances contained in said products and is formed by gas, vapour and liquid particles. In particular, water, propylene glycol and more dense glycerin are used to obtain a "smoking" effect. In essence, by evaporating a mixture of these substances, an aerosol is produced at a temperature which is related to the percentage of each component.

Specifically, the aerosol is intended to simulate the smoking effect obtained by the combustion of tobacco, while having the function of extracting nicotine from tobacco or extracting active ingredients such as THC (Δ -9-tetrahydrocannabinol) or CBD (cannabidiol) from other plant substances.

In more detail, the device heats the air to a temperature in the range of 160 ℃ to 250 ℃, wherein propylene glycol has a boiling point of 188.2 ℃, glycerol has a boiling point of 290 ℃, nicotine has a boiling point of 247 ℃, THC has a boiling point of 157 ℃, and CBD has a boiling point of 160 ℃ to 180 ℃.

Both water and propylene glycol are excellent solvents, both of which are effective in dissolving nicotine and sufficiently extracting THC and CBD. Suitably, the solubilising and stripping effect on the active ingredients and aromas contained in the plant matter itself is achieved by passing a warm flow of air and propylene glycol vapour and water through the plant matter (tobacco, THC and/or CBD based extracts).

The characteristics of the aerosol depend primarily on the power applied to the heating coil of the heating device, which determines the temperature of the air passing through the HnB product based on the physical characteristics of the HnB product formulation (e.g., viscosity and wettability) and the specific heat capacity of the formulation. In addition, the pressure drop, airflow rate, and aerosol density between and within the heating devices may vary.

At present, HnB solid smoking products are often prepared using flowers of reconstituted tobacco (reconstituted tobaccos) and/or cannabis plants, with the addition of additives aimed at reducing and improving the thermal conductivity of the plant matter and at the same time reducing its burning rate.

As is known, reconstituted tobacco is obtained from tobacco powder to which various substances have been added to enable the production of:

-tobacco sheets obtained by casting from "slurry" and/or by rolling with a technique corresponding to paper making, and then used to obtain cigarettes for use in heating devices;

tobacco particles, obtained by extrusion, and then used in heating devices.

In particular, in order to obtain both forms of reconstituted tobacco, dedicated plants (dedicated plants) are used, which have a great impact on the environment due to the use of large quantities of:

-water;

-an energy source for grinding tobacco and dry powder, wherein water and other liquids are added to the dry powder in such amounts that the absolute humidity of the product to be dried, calculated on a wet basis, may be in the range of 50% -85%.

These special devices for the preparation of reconstituted tobacco are completely different from conventional devices, i.e. from devices (plants) for the production of conventional cigarettes, cigarillos or for the preparation of cut tobacco, known as "manual cigarettes", and/or tobacco product pipe tobacco and other tobacco burning products.

Furthermore, the dedicated equipment for the preparation of reconstituted tobacco is extremely expensive, in particular in comparison with the above-mentioned conventional equipment provided for the production of tobacco for use in said tobacco-burning products/cigarettes.

In particular, for cut filler produced in conventional equipment and thus used to prepare tobacco burning type cigarettes, it is common that the propylene glycol content in the cut filler is less than 5% on a moisture free basis, and the cut filler has a burning rate suitable for its use. In these plants, at the end of the production process, the final absolute humidity of the cut tobacco is in the range 12% -18%, measured on a wet basis, and the humidity of the cut tobacco is comprised in the range 18% -35%, after cutting and before final drying.

However, for conventional cut filler used in smoking products (cigarettes) intended to burn (also known as "lit cigarettes"), if used in such HnB products, i.e., heated but not burned, sufficient aerosol cannot be formed due to the low levels of propylene glycol and/or other additives.

On the other hand, a known solution is to add additives for flame retardancy to the tobacco leaves before cutting, for which purpose e.g. sodium chloride may be used.

In addition, the propylene glycol and/or glycerin added to the tobacco leaves cannot exceed 6% by weight, and if so, the cutting machine currently used in conventional equipment cannot normally cut/shred tobacco to which additives are added at this level. In particular, it has been noted that propylene glycol and glycerin also act as lubricating substances, the addition of large amounts (greater than 4% -5%) of which to the tobacco reduces the friction between the tobacco and the mechanism (track) that advances and compacts the tobacco towards the cutting mouth of the cutting machine; in this case, in fact, the tobacco tends to slide and advance discontinuously towards the cutting mouth of the cutting machine, resulting in a non-uniform width of the cut pieces obtained, with a high yield of waste and fines.

Basically, the reconstituted tobacco currently used for the HnB product and obtained by the dedicated equipment described above, preferably shredded tobacco (obtained by conventional equipment and intended for use in smoking products where the tobacco is burned), exhibits at least the following two characteristics:

-being able to generate an aerosol with a propylene glycol content of more than 10% calculated on a dry basis, an

Slow burning speed.

In this regard, for example, WO 2017/051034 describes a process for producing reconstituted tobacco in a device for heating tobacco without burning the tobacco. The process provides for the addition of a humectant, such as glycerin or propylene glycol, to the water-soluble tobacco portion (i.e., the portion that includes all of the water-soluble tobacco components) in an amount in the range of 1% to 25% on a reconstituted tobacco anhydrous basis. In particular, the tobacco portion to which the humectant, in particular propylene glycol, is added is obtained by immersing the tobacco mixture in water and then separating the soluble portion from the fibrous portion, in particular by mechanical pressing. In any case, the process provides for the addition of propylene glycol in the conventional processes for manufacturing reconstituted tobacco, i.e. in processes for producing paper ("paper") type or cast type or extrusion type. Specifically, in the case of reconstituted tobacco obtained using the same process as paper making, propylene glycol is added to the tobacco sheet prior to cutting the sheet.

CN108713788 also describes a process for producing reconstituted tobacco for use in heat-non-burn (HnB) type cigarettes. Specifically, the process provides starting materials comprising 50% to 80% tobacco, 10% to 30% of a misting agent (which may be glycerin or propylene glycol), 0.5% to 10% of a binder, 0.01% to 1% of a bulking agent, 5% to 15% of a flavor additive, and 0% to 30% water. These materials are mixed and then subjected to a rolling treatment to obtain a tobacco sheet, which is then cut. Also in this case, the aerosol is added to the tobacco mixture prior to cutting.

Furthermore, US2006/0021626 describes a filler material for smoking products which burns quickly, releases a large amount of smoke and is not easily extinguished. Thus, the filler material is used to prepare a burning smoking product of the cigarette type, rather than the "heat-not-burn" (HnB) type, i.e., "heat without burning". In addition, a humectant (e.g., glycerin or propylene glycol) is added to the tobacco mixture prior to cutting the tobacco mixture. In any case, in fact, US2006/0021626 provides a filler material obtained with a traditional process intended for the production of reconstituted tobacco, i.e. with a process for the production of paper ("paper") type or of the cast type or of the extrusion type.

The object of the present invention is to solve the above mentioned drawbacks of the traditional solutions by proposing a process for obtaining a solid cigarette-like heated but not burning (HnB) smoking product by using cut tobacco and/or flowers of cannabis plants, the characteristics of which are substantially identical, or even better, than those obtained with reconstituted tobacco alone or mainly.

Another object of the invention is to propose a process that enables solid smoking products to be obtained from cut tobacco, which products do not burn but produce aerosols if heated.

It is another object of the invention to provide a process that can save energy.

It is another object of the invention to provide a process that can be performed in a simple, fast and low cost manner in conventional systems.

It is another object of the invention to provide a process that can be performed in a system at low manufacturing costs.

It is a further object of the present invention to provide an ecologically sustainable process, and in particular a process that enables a reduction in energy and water consumption.

It is another object of the present invention to provide a process for preparing a heated, non-burning (HnB) solid smoking product that does not require the use of reconstituted/homogenized tobacco and, therefore, does not require the use of equipment currently planned for preparing reconstituted/homogenized tobacco.

It is another object of the present invention to provide a process for preparing a solid smoking product for a heated but non-burning (HnB) cigarette which does not require the production of tobacco sheets to be dried and/or cut by casting or rolling.

Another object of the invention is to propose a process whose characteristics are comparable to or better than those of the conventional processes.

All these objects, alone or in any combination thereof, as well as others which will become apparent from the following description, are achieved according to the present invention by a process having the features indicated in claim 1 and a solid smoking product of the heated but not burning (HnB) type having the features indicated in claim 40.

The invention will be further elucidated in some preferred embodiments, which are described for exemplary and non-limiting purposes only, with reference to the following drawings, in which:

figures 1a and 1b show in schematic views respectively a cigarette retaining roller and a needle retaining roller (drum) arranged in a roller device usable in the process according to the invention,

fig. 2a and 2b show in schematic views different variants of a cigarette holding roller and a needle holding roller, respectively, in a further device for use in the process according to the invention, and

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

First, it is expressly intended that all humidity values defined herein and set forth below are determined on a wet basis from a measurement system. In particular, the moisture value is defined as the percentage of water contained in the total mass of the respective product, in other words, the moisture value is the percentage of the amount of water to the total mass of the mixture of water and tobacco. Suitably, these values are obtained using conventional processes for measuring the amount of Water in products provided in the literature, such as the processes mentioned in Niers Rose (Nils Rose) et al, status report on Moisture, Water and Oven Volatiles common in the Tobacco industry (Tobacco Moisture, Water and Oven Volatiles used with the tobaca process) in Analytical and bioanalytical chemistry (Analytical and bioanalytical chemistry) (7.1.2014., pages 1-16).

It is also specified below that, for solid smoking products (articles) of the "heat-not burn" type that generate aerosols based on tobacco and/or cannabis plant extracts, we mean products that heat the tobacco-based material and/or cannabis plant extract without burning, in particular, the material is not expected to burn, in order to generate aerosols. Preferably, the aerosol-generating heat-not-burn product comprises a tobacco-based material and/or an extract of a cannabis plant, which material is to be heated (particularly at relatively low temperatures) to form a vapour (aerosol), but to avoid ignition and combustion of the material.

In particular, solid smoking articles (articles) of the "heat-not-burn" type (i.e. "heat without burn") according to the invention, such as cigarettes, comprise only tobacco or tobacco-based material, which, unlike conventional cigarettes (i.e. "lit cigarettes"), is not combustible.

Suitably, a "heated but non-burning" solid smoking product includes what is known as an "electrically heated tobacco product" (abbreviated as "EHTP"), which is a product that does not ignite so that the tobacco does not burn, as discussed on pages 1-14 of Verification of the absence of a burning process in Electrically Heated Tobacco Systems (EHTS) by o.fujita and h.yan on day 11/6 of 2015. In particular, these products are not heated to the ignition temperature of the tobacco-based material and/or to a non-burning flame, and therefore no combustion occurs.

Advantageously, the process according to the invention provides, in particular and exclusively, the preparation of solid smoking products of the tobacco and/or cannabis based (i.e. containing tobacco and/or cannabis) heated without combustion ("heated but not combusted") type.

Preferably, the solid smoking product is of the heated non-burning ("heat-non-burning") cigarette type and it produces an aerosol.

"Natural tobacco" refers hereinafter to tobacco that is free of (and therefore does not have added) additives, binders, and the like; further, suitably, "natural tobacco" refers to tobacco that is not a "reconstituted" or "homogenized" type of tobacco.

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

-preparing a mixture of tobacco and/or hemp; preferably, preparation is carried out by composing groups (also called "batches") containing various tobacco packets (e.g. in boxes, bales, etc.) according to the expected percentage of each type of tobacco; preferably, the absolute humidity of the tobacco during this stage is between about 10% and 14%,

-moistening and tanning the tobacco and/or hemp mixture thus prepared by moistening with water and adding liquid and solid additives; suitably, the addition of water and additives is adjusted according to the weight of the tobacco, preferably this stage is carried out in a specific cartridge; preferably, the absolute humidity of the tobacco during this stage is between about 17% and 30%,

-mixing and storing the tobacco and/or the pre-prepared hemp mixture in suitable containers (silos),

-discharging and mixing the tobacco and/or the reserved cannabis mixture,

-cutting the tobacco and/or the reserved cannabis mixture to obtain a tobacco or cannabis-based cut material; advantageously, the cut width of the tobacco depends on the end use of the tobacco itself, in particular, the cut of a manual cigarette uses a finer cut, the cut of a cut of tobacco pipe uses a wider cut,

-drying the cut material; advantageously, the drying can be carried out in a drying drum, a fluidized bed or a pneumatic conveying device; suitably, the drying temperature is greater than about 100 ℃; suitably, the absolute humidity of the product at the end of this stage is about 12% to 16%,

-mixing and storing the cut and dried material;

-preparing (packaging) solid smoking products (cigarettes) using the cut material thus prepared; in particular, at this stage, the cut and dried material (possibly together with the filter) is wrapped with a paper tube, so as to obtain the traditional conformation of the cigarette.

Preferably, after the step of mixing and storing the cut and dried material, the process according to the invention may also comprise a step of imparting a flavour to the product thus prepared in a suitable cylinder, suitably adding an alcohol-based and/or water-based liquid additive to improve the flavour of the product. Suitably, the addition of the additive is adjusted according to the weight of tobacco present in the cut and dried material. Advantageously, the cut material with flavour is mixed and stored prior to production/packaging of the solid smoking product.

Preferably, the packaged solid smoking products (i.e. cigarettes) can then be packaged in groups, in particular, in which a plurality of products are inserted into the package and then appropriately closed and sealed.

Preferably, the above-mentioned steps of the process according to the invention can be carried out with conventional systems, i.e. in those apparatuses for producing solid smoking products for the ignition and combustion of tobacco, such as conventional cigarettes, cigarillos, cut tobacco for the preparation of so-called "manual cigarettes" and/or pipe tobacco.

Preferably, the process according to the invention can be carried out in conventional plants of the type currently used for the combustion of products/preparations, which are therefore different from the known dedicated systems currently provided for obtaining reconstituted/homogenized tobacco.

Conveniently, the process according to the invention does not provide any preliminary step of mixing the tobacco powder obtained by comminuting the solid components of the tobacco with other substances (water, binders, aerosol-forming materials) in order to form a paste or "slurry" to be poured, laminated or extruded.

Conveniently, the process according to the invention is not provided in any way for the manufacture of tobacco sheets and, in particular, does not comprise a step of manufacturing tobacco sheets. In more detail, in the process according to the invention, no paste or "slurry" is formed and cast, neither a rolling step by rollers nor an extrusion step to obtain tobacco particles.

The process according to the invention provides for the addition of not less than 6% by weight of propylene glycol, calculated on the anhydrous basis of the cut material, to tobacco and/or hemp-based cut material.

Preferably, the process according to the invention provides for the addition to the cut tobacco and/or hemp-based material of propylene glycol in a percentage by weight equal to about 6% to 30%, preferably equal to about 10% to 21%, on a water-free basis of the cut material.

Preferably, the cut material to which propylene glycol is added consists only of natural tobacco. Preferably, the cut material to which propylene glycol is added does not comprise reconstituted/homogenized tobacco. Preferably, the cut material to which propylene glycol is added may consist of a mixture of natural tobacco and reconstituted/homogenized tobacco. Preferably, the process according to the invention provides for the addition to the cut tobacco and/or hemp-based material of propylene glycol in a percentage by weight equal to about 10% -21% on the anhydrous basis of the cut material.

Advantageously, the process according to the invention provides for the addition to the cut material of tobacco and/or hemp base of propylene glycol in a percentage by weight equal to about 6% to 30%, preferably equal to about 10% to 21%, on a dry basis of the cut material. Preferably, only propylene glycol is applied directly to the cut tobacco; suitably, this simplifies the production scheme and optimises the amount of propylene glycol added.

Suitably, the propylene glycol is not added to and/or combined with a binder and is not applied to a substrate/carrier other than tobacco. Conveniently, in the process according to the invention, the tobacco to which the propylene glycol is added is not bound to the binder, either before or after cutting and either before or after addition of the propylene glycol. Conveniently, the process according to the invention provides for the addition of propylene glycol directly to the product consisting only and exclusively of cut tobacco, in a percentage by weight on a moisture free basis of the cut material equal to about 6% to 30%, preferably equal to about 10% to 21%.

Advantageously, the process according to the invention provides for the addition directly to the material of propylene glycol equal to about 6% -30%, preferably equal to about 10% -21%, by weight on a water free basis of the cut material, this material consisting exclusively of tobacco that has been cut/cut into strips by a cutting machine (for example, of the type known as "cut filler").

Conveniently, the process according to the invention provides for the sole and exclusive addition, as substance/agent for forming the aerosol, of propylene glycol in a percentage by weight on a water-free basis of the cut material equal to about 6% -30%, preferably equal to about 10% -21%.

Conveniently, the process according to the invention provides for the addition of the following ingredients as substances/agents for forming an aerosol:

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

-glycerol or other substances, in percentages by weight on a water free basis of the cutting material lower than propylene glycol.

Conveniently, the process according to the invention provides for the addition of at least one substance/agent for forming an aerosol directly on tobacco that has been cut/cut into strips, which substance/agent:

-consisting solely of propylene glycol in a percentage by weight equal to about 6% to 30%, preferably equal to about 10% to 21%, based on the anhydrous basis of the cutting material, or

-consisting of propylene glycol in a percentage equal to about 6% to 30% by weight on a water free basis of the cutting material, preferably equal to about 10% to 21%, and also of glycerol always defined as a percentage by weight on a water free basis of the cutting material lower than propylene glycol.

In particular, propylene glycol is advantageously preferred over other substances/agents capable of forming an aerosol, since its boiling point (about 188 ℃) is lower than that of nicotine (about 247 ℃) so that a suitable aerosol can be produced without removing most of the aromatic and volatile substances in tobacco, in particular extracting a more precise amount of nicotine, and without causing its denaturation. In contrast, for example, glycerin has a boiling point of about 290 ℃ higher than that of nicotine (about 247 ℃), requiring the tobacco to be heated to an excessively high temperature, thus resulting in uncontrolled extraction of nicotine. Furthermore, advantageously, the use of propylene glycol allows the tobacco-based material to be heated at lower temperatures during use, thus limiting the energy consumption of the device with which a smoking product comprising said tobacco-based material is heated to generate an aerosol.

Advantageously, the process also provides for the addition of glycerin to the cut tobacco or hemp based material.

Conveniently, in the process of the present invention, glycerin, if provided, in a percentage amount less than propylene glycol is added to the cut tobacco.

Preferably, in any case, the addition of propylene glycol and/or glycerol is carried out on tobacco and/or hemp based cut material. Suitably, in this way, the amount of propylene glycol and/or glycerol used can be precisely controlled.

Advantageously, the process also provides for the addition of additives to the cut tobacco or hemp based material. Preferably, the additive comprises a flame retardant additive, such as sodium chloride. Suitably, the additives may be selected to tailor the product or to alter its organoleptic properties.

Preferably, in the process according to the invention, propylene glycol, glycerol and possible additives are the only substances added to the cut tobacco. Specifically, for example, no binding substance is added, such as cellulose fibers, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, hydroxyethyl cellulose, microcrystalline cellulose, methyl cellulose, carboxymethyl cellulose (CMC), corn starch, potato starch, guar gum, carob gum, pectin (e.g., tobacco pectin), and alginate compounds (e.g., ammonium alginate and sodium alginate).

Advantageously, the process according to the invention, particularly and exclusively for the preparation of solid smoking products of the type which are heated without combustion ("heated without combustion"), comprises the following stages, in which:

-obtaining at least one type of tobacco leaves,

moistening the tobacco leaves, preferably by moistening with/in water, the tobacco leaves being pre-mixed,

-mixing, preferably mechanically mixing, the obtained tobacco leaves,

-cutting the moistened tobacco leaves to obtain cut tobacco,

-adding to the cut filler thus obtained propylene glycol in a percentage equal to about 6% to 30%, preferably equal to about 10% to 21%, by weight on a cut filler anhydrous basis.

Suitably, the process further comprises the step of drying the cut tobacco.

Conveniently, the process also comprises a step of packaging the dried shredded tobacco with a covering/wrapping material, so as to obtain a solid smoking product of the type that is heated without combustion (i.e. of the "heated but not burnt" type, "HNB").

Conveniently, the process also comprises a step of packaging a plurality of solid tobacco products of the type which are heated without combustion (i.e. of the "heated but not burnt" type, "HnB"), each of which is obtained by packaging shredded tobacco with a coating/packaging material.

Preferably, the process according to the invention provides for the addition to the cut filler, immediately after cutting, of propylene glycol in a percentage by weight on a dry basis of the cut filler equal to about 6% to 30%, preferably equal to about 10% to 21%.

Preferably, the process according to the invention provides for the addition to the shredded tobacco of propylene glycol amounting to about 6% to 30% by weight, preferably to about 10% to 21% by weight, on a shredded tobacco anhydrous basis, immediately before and/or during drying of the shredded tobacco and/or immediately after drying of the shredded tobacco.

Preferably, the process according to the invention provides for the addition to the cut filler, immediately before and/or during packaging of said cut filler and/or immediately after packaging of said cut filler, of propylene glycol in a percentage by weight on a cut filler anhydrous basis equal to about 6% to 30%, preferably equal to about 10% to 21%, to form a solid smoking product of the type which is heated without combustion (i.e. of the "heated but not burnt" type, "HnB").

Preferably, the process according to the invention provides for the addition to the shredded tobacco, immediately before and/or during and/or immediately after the packaging of the plurality of solid smoking products, of propylene glycol equal to about 6% to 30%, preferably equal to about 10% to 21%, by weight on a shredded tobacco anhydrous basis, of the type which is heated without combustion (i.e. "heated but not combusted" type, "HnB"), and obtained by packaging said shredded tobacco.

Basically, suitably, the process of the invention provides for the addition of propylene glycol in one or more successive stages with respect to obtaining a cut material, in a percentage by weight equal to about 6% to 30%, preferably equal to about 10% to 21%, on a water-free basis of the cut material.

Preferably, the process according to the invention, particularly and exclusively for the preparation of solid smoking products of the type which are heated without combustion ("heated without combustion"), comprises the following stages, in which:

-taking a lobe of at least one type of tobacco on a processing line, and separately taking a tobacco stem on another processing line; suitably, for this purpose, the tobacco leaves are usually pre-treated in the plant and/or in dedicated processing lines/areas, in order to separate the margins from the stems,

wetting the leaf margins and the stems, preferably with water, on the respective/separate processing line,

mixing, preferably mechanically mixing, the margins and stalks obtained on respective/separate processing lines,

-keeping the wetted tobacco lamina and the wetted tobacco stem always on respective/separate processing lines, performing a cutting of the wetted tobacco lamina and the wetted tobacco stem to obtain cut tobacco flaps and cut tobacco stems,

-adding to the cut tobacco lobes and/or to the cut tobacco stems a pre-obtained propylene glycol, in a percentage by weight on a moisture free basis of the respective material equal to about 6% -30%, preferably equal to about 10% -21%.

Suitably, during and/or after the moistening step but before the cutting step, the margins and/or the tobacco stems may be added with less than 5% by weight of propylene glycol and/or glycerol or sorbitol on a moisture free basis of the tobacco leaf.

Suitably, the process further comprises the step of drying the cut leaflets and cut tobacco stems, preferably on respective/separate processing lines. Conveniently, the cut and dried lobes (obtained on the first processing line) are combined/mixed with the cut and dried tobacco stems (obtained on the other processing line) after drying and before packaging the solid smoking product, preferably before perfuming.

Advantageously, said tobacco or hemp-based cut material is of the type used for producing tobacco-burning solid smoking products, such as conventional cigarettes (i.e. of the burning type, known as "lit cigarettes", cigarillos, for preparing tobacco and/or cut tobacco pipes, known as "handmade cigarettes").

In particular, the tobacco and/or hemp-based cut material obtains the formation of chips from the wetted and stored tobacco and/or hemp blend by cutting with a width substantially in the range of 0.12-2.5mm ("cut width"). Suitably, the cut material comprises only or predominantly pieces of a mixture comprising tobacco and/or hemp having a width of about 0.12-2.5 mm. Suitably, the cut material is formed from tobacco fragments obtained from a mixture of the same type or even different types of tobacco.

Advantageously, the process according to the invention provides for the addition of propylene glycol, glycerol and/or other additives to the cut material consisting of a mixture of shredded tobacco, preferably of various types of tobacco 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 the cut tobacco, since all the components of the different types of tobacco originally used to form the mixture are more visible in the cut tobacco than in a one kilogram leaf flap (strip).

Advantageously, in the process according to the invention, liquid propylene glycol and/or glycerol and/or other additives are added, wholly or in part, in one or more of the following stages:

immediately after the cutting stage of the tobacco and/or hemp mixture, and/or

-after a drying phase of the cut material and/or after a flavour addition phase, and/or

During the packaging stage (production) of the solid smoking products (cigarettes) comprising the cut material, and/or

After the packaging (production) phase of the solid smoking products (cigarettes) containing the cut material,

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

Conveniently, in the process of the invention, propylene glycol and/or glycerol and/or other additives may be added in only one of the above stages, so that in a single stage propylene glycol substantially amounts to between about 6% and 30%, preferably between about 10% and 21%, by weight on a cut material anhydrous basis.

Conveniently, in the process according to the invention, propylene glycol and/or glycerol and/or other additives may be added in part in two or more (or even all five) of the above steps, so that the final and overall weight percentage of propylene glycol of the cut material in the smoking solid product thus obtained is equal to about 10% -21% on a cut material anhydrous basis.

Advantageously, in the process according to the invention, liquid propylene glycol and/or glycerol and/or other additives may be added in part before cutting the tobacco and/or hemp-based material, preferably during the wetting step. It will be understood, however, that prior to cutting the tobacco, preferably during the moistening step, propylene glycol is added to the tobacco such that the propylene glycol is equal to or less than about 5% by weight on a moisture free basis of the cut material.

Suitably, the process according to the invention may comprise:

no (and thus no) propylene glycol is added to the tobacco prior to cutting,

-adding to the tobacco itself, after cutting said tobacco, less than 6% by weight of propylene glycol on a cut filler anhydrous basis.

Suitably, the process according to the invention may comprise:

-adding less than 5% by weight of propylene glycol on a moisture free basis of the cut material to the tobacco, preferably to wet the tobacco, prior to cutting the tobacco.

-after cutting the tobacco (less than 5% by weight propylene glycol on a tobacco anhydrous basis has been added to the tobacco before cutting), less than 6% by weight propylene glycol on a tobacco shred anhydrous basis is added thereto.

Conveniently, the process of the invention comprises adding less than 5% by weight of glycerol, based on the anhydrous basis of the tobacco to be cut, to the tobacco, preferably moistening the tobacco, prior to cutting the tobacco.

Advantageously, the process according to the invention comprises adding sorbitol to the tobacco, preferably moistening the tobacco, before cutting the tobacco itself.

Conveniently, the process according to the invention comprises adding water only to the tobacco prior to cutting the tobacco.

Conveniently, the process of the invention comprises adding only less than 5% by weight of propylene glycol and/or glycerol and/or sorbitol on a moisture free basis of the tobacco to the tobacco itself prior to cutting the tobacco.

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

Advantageously, in the process according to the invention, propylene glycol and/or glycerol and/or other additives can be added, in whole or in part, immediately after the drying step or after the perfuming step. Conveniently, in this case, the propylene glycol is added in an amount equal to 3% -30% by weight of the anhydrous weight of the cut material to be treated, preferably equal to 6% -22% by weight of the anhydrous weight of the cut material to be treated.

Advantageously, for the addition of propylene glycol and/or glycerol and/or other cutting additives, the material is laid on a belt conveyor with an adjustable feed speed. Conveniently, by varying the speed of the conveyor belt, the thickness of the layer of cut material formed on the conveyor belt can be varied, with the rate of accumulation of the cut material on the conveyor belt and the width of the belt itself being constant. Advantageously, in this way the use of a drum similar to that used for tanning or perfuming is avoided, which, when used, can lead to the formation of undesired balls of tobacco due to the difference in speed existing between the peripheral speed of the drum and that of the conveyed cut material.

Advantageously, means for spraying one or more liquid substances onto the layer of cut material deposited on the belt are provided above the conveyor belt. Advantageously, the liquid substance added to the cut material deposited on the conveyor belt, preferably by spraying and/or misting, comprises propylene glycol. Preferably, the liquid substance added to the cut material accumulated on the conveyor belt, preferably by spraying and/or misting, comprises propylene glycol mixed with water and/or other additives for improving the final quality of the product.

Preferably, the spraying means comprises a nozzle with an adjustable flow rate to enable easy adjustment of the spraying system to the amount of liquid to be added.

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

Advantageously, the liquid substance added to the cut material accumulated on the conveyor belt, preferably by spraying and/or misting, may also comprise water. Suitably, water is used to improve the absorption of liquid by the cut material.

Suitably, after cutting, the cut material is dried. Preferably, the cut material is subjected to a drying step, in particular in the case of adding water to the cut material. Advantageously, the drying is carried out in a convection dryer and/or a conduction dryer, wherein the temperature of the heating fluid and the contact wall is between 30 ℃ and 130 ℃, preferably between 50 ℃ and 90 ℃.

Conveniently, in the process according to the invention, the drying step is carried out at a temperature lower than that provided by the prior art, thus making it possible to avoid removing most of the aromatic and volatile substances of the tobacco. This is advantageous as it avoids evaporation of the propylene glycol so that the amount of propylene glycol in the cut material subsequently used in the solid smoking product remains substantially unchanged. In contrast, in the case of drying at temperatures above 130 ℃, as envisaged in the prior art, it is necessary to use glycerol and/or other aerosol-forming substances/agents capable of withstanding drying temperatures above 130 ℃ in addition to and/or in place of the propylene glycol which evaporates at the above-mentioned temperatures.

Advantageously, in the process according to the invention, propylene glycol and/or glycerol and/or other additives may be added, in whole or in part, during and/or after the step of wrapping the cut material, in order to obtain solid smoking products of the type which are heated without burning (i.e. "heated but not burning", "HnB"), preferably cigarettes with or without filters.

Suitably, solid smoking products, in particular cigarettes, which are heated without combustion (i.e. "heated but not combusted" type, "HnB") are packaged by wrapping and containing a tobacco and/or hemp based cut material with an outer covering/wrapping material (preferably defined as a paper sleeve).

Advantageously, the outer covering/wrapping material may comprise a paper having a low burn rate and/or may contain a fire retardant substance on its inner surface while preventing air flow between the outer and inner surfaces of the outer covering/wrapping material.

The solid cigarette smoking product may be:

no filter when it comprises only an outer covering/wrapping material (i.e. a paper cylinder) and the tobacco and/or hemp-based material to be heat-cut contained therein;

when a cylindrical element of filter material is also employed at one end, with a filter.

Conveniently, the wrapping step refers to the step of wrapping an outer covering/wrapping material (i.e. a paper tube) around the tobacco and/or hemp-based cut material to be heated (possibly together with the filter) to obtain the smoking product (i.e. the cigarette).

Advantageously, for the addition of a liquid comprising propylene glycol and/or glycerol and/or other additives during and/or after packaging of a solid smoking product of the heated but not burning ("HnB") type (i.e. a cigarette), a liquid dosing device of a first type, preferably of a conventional type, can be used.

Advantageously, this first type of liquid dosing device comprises an application mechanism, such as a needle or a nozzle/sprayer, for applying the above-mentioned liquid onto the cut material in the cigarettes to be packaged/packaged.

Conveniently, the amount of such liquid added depends on the weight of the tobacco and/or hemp-based cut material to be heated present in the wrapped/to-be-wrapped cigarette. In particular, for a weight to the cutting material to be heated equal to or less than about 500mg, suitably the liquid to be added (comprising propylene glycol and/or glycerol and/or other additives) is substantially in the range of 4% -20% of the anhydrous weight of the cutting material to be heated, in particular about 20-100 mg.

Suitably, as shown in fig. 1a, the first liquid dispensing device comprises a rotating needle-holding drum 3, preferably a series of needles 4 for injecting liquid, mounted on said rotating drum.

The cigarette wrapping machine comprises a respective rotating cigarette-holding drum 5, the drum 5 having a plurality of cavities 6 provided on the side surface of the drum, each cavity 6 containing a cigarette 7 during or after wrapping (see figure 1 b). Conveniently, each cigarette 7 is held in the corresponding cavity 6 by a pneumatic system.

Conveniently, the rotating needle-holding drum 3 of the liquid dispensing device is positioned facing the rotating cigarette-holding drum 5 of the packaging machine so that each injection needle 4 axially faces a cigarette 7 (see fig. 3). Advantageously, the needle-holding roller 3 is coaxial with the cigarette-holding roller 5, and moreover, each needle 4 of the first roller is coaxial with a respective cigarette 7 housed in the second roller. Advantageously, the two

drums

3, 5 have the same rotational speed.

Suitably, therefore, during and/or after the packing (production) phase of the cigarettes, each needle 4 of the dosing device injects a corresponding quantity of a predetermined liquid into the facing cigarette 7 during or after packing.

Conveniently, in the embodiment shown in figures 1a and 3, as described above, the application means comprise a series of needles 4, preferably coaxial with the cigarette 7 that they face, configured to penetrate inside the cigarette 7 and to inject a predetermined quantity of liquid directly inside the cigarette.

In another embodiment (not shown), the application mechanism may comprise a nozzle configured to spray/mist the liquid onto the cut material of the cigarette 7, preferably from a close distance.

Advantageously, the propylene glycol, glycerin and/or other additives may be added directly as described above, and/or may be added indirectly by introducing/inserting capsules containing liquid propylene glycol, glycerin and/or other additives into the cigarette at the tobacco and/or cannabis based cut material. Conveniently, these capsules, inserted into the cut material contained in the packaged or to be packaged cigarette, open and/or rupture as a result of the pressure, so that the propylene glycol, glycerine and/or other additives contained in the same capsules impregnate the tobacco material of the cigarette. Conveniently, this technique of introduction/insertion through the capsule corresponds to the technique already used for inserting capsules to aromatise the aerosol inside cigarette filters, however with the difference that in this case the capsule is inserted inside the cut tobacco and/or cannabis based material.

Advantageously, in the process according to the invention, propylene glycol, glycerine and/or other additives may be added, in whole or in part, during the packaging step of smoking products of the heated but not burnt ("HnB") type, in particular of the cigarette type.

Advantageously, in order to add a liquid comprising propylene glycol and/or glycerol and/or other additives during the step of packaging the cigarettes, a liquid dosing device of a second type, preferably of a conventional type, can be used.

Advantageously, this second type of liquid dispensing device comprises an application mechanism, such as a needle or a nozzle/sprayer, for applying the above-mentioned liquid to the cut material in the cigarettes to be packaged/packaged.

Suitably, as shown in fig. 2a, the liquid dispensing device comprises a rotating needle holding drum 10, the rotating needle holding drum 10 preferably comprising a series of needles 11 for injecting the liquid. In particular, the needles 11 are subdivided into a series of groups 12, the groups 12 being suitably mounted on the rotating drum.

The cigarette wrapping machine comprises a respective rotating cigarette-holding drum 13, on the side of which a plurality of moulds 14 are provided, each containing a predetermined number of cigarettes 15 to be wrapped. Conveniently, the position of each cigarette 15 within the tile 14 is fixed and predetermined.

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

Conveniently, therefore, during the packaging step, each needle 11 of the measuring device conveniently injects a corresponding quantity of a predetermined liquid into the facing cigarette 15, in particular onto the cut material inside the cigarette. Advantageously, the two

cylinders

10 and 13 have the same rotation speed.

Conveniently, in the embodiment shown in figures 2a and 3, as described above, the application mechanism comprises a series of needles 11, the needles 11 preferably being coaxial with the cigarette 15 that they face and being configured so as to be able to penetrate inside the cigarette 15 and to inject a predetermined quantity of liquid directly inside the cigarette.

In another embodiment (not shown), the application mechanism may include a nozzle configured to spray/mist the liquid onto the cut material of each cigarette, preferably from a close distance.

Conveniently, the invention also relates to a smoking article, preferably in the form of a cigarette and/or a rod, which is heated without combustion (i.e. "heated without combustion" or "HnB"), comprising at least one portion for generating an aerosol, which is wrapped in an outer covering/wrapping material and comprises cut tobacco to which, after cutting, propylene glycol is added in a percentage by weight, based on the anhydrous basis of the cut tobacco, of between about 6% and 30%, preferably equal to between about 10% and 21%.

Conveniently, the smoking product/article is constituted solely and exclusively by the portion to produce the aerosol.

Advantageously, the smoking product/article further 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 filter material.

Preferably, said portion that generates the aerosol comprises only cut tobacco to which, after cutting, propylene glycol is added in a percentage equal to about 6-30% by weight on a cut tobacco anhydrous basis, preferably equal to about 10-21%.

Preferably, said portion that generates the aerosol comprises only cut tobacco to which, after cutting, are added:

-propylene glycol in a percentage by weight on a tobacco anhydrous basis equal to about 6-30%, preferably equal to about 10-21%, and

-glycerol in a lower percentage than propylene glycol.

Advantageously, the portion from which the aerosol is generated does not comprise ligands such as alginates, hydroxypropyl cellulose, hydroxypropyl methylcellulose, hydroxyethyl cellulose, microcrystalline cellulose, methylcellulose, carboxymethylcellulose (CMC), corn starch, potato starch, guar gum, carob flour, pectin and alginates (e.g. ammonium alginate and sodium alginate which have been added to cut tobacco). Conveniently, the cut tobacco does not contain the above-mentioned binder in its interior. Preferably, the portion that generates aerosol does not comprise cellulose added to the cut tobacco. Preferably, the tobacco thread is cellulose-free.

Conveniently, the portion that generates the aerosol may comprise reconstituted/homogenized tobacco in addition to the tobacco. Advantageously, the shredded tobacco is obtained by mixing (preferably mechanically mixing) only natural tobacco of the same type or of different types.

Advantageously, the cut tobacco is obtained after mixing of the wetted lobes, preferably with a moisture content of about 17-30%.

Advantageously, natural tobacco (of the same type or of a different type) is mixed, preferably mechanically, with reconstituted/homogenized tobacco, obtaining said cut tobacco.

Advantageously, the portion that generates aerosol may be immediately adjacent the end portion configured to be positioned in the mouth.

Advantageously, the smoking product, preferably of the cigarette type, which is heated without combustion (i.e. "heated but not burnt" or "HnB") consists only of said outer portion, which is configured to be positioned in the mouth, from which portion an aerosol is generated.

Advantageously, the smoking article/article, preferably of the cigarette type, which is heated without combustion (i.e. "heated without combustion" or "HnB"), comprises a portion or combustible element for generating heat, configured to combust during use to generate heat to heat the portion, thereby generating an aerosol. Conveniently, the portion or the fuel element for generating heat is physically spaced/distinct from the portion to generate aerosol. Conveniently, the portion or the fuel element for generating heat is positioned relative to the portion to generate aerosol so that heat transfer may occur by conduction and/or convection.

Advantageously, said smoking article/article, preferably of the cigarette type, which is heated without burning (i.e. "heated without burning" or "HnB"), may be coupled and/or incorporate and/or insert a heating means configured to enable heating of the portion configured for generating the aerosol. Preferably, the heating means is configured not to combust the portion configured to generate aerosol. Preferably, the heating means is separate and distinct from the smoking article/article. In this way, drying of the tobacco-based product can be suitably reduced, thereby preserving its flavor.

None of the prior documents WO 2017/051034, CN108713788 and US2006/0021626 teach the addition of not less than 6% by weight of propylene glycol on a cut filler basis to cut tobacco.

In particular, WO 2017/051034 teaches the addition of propylene glycol to a soluble aqueous component, which component is added to tobacco fibre sheets (in particular reconstituted tobacco) after concentration, and then cutting the sheets so obtained. Thus, in WO 2017/051034, propylene glycol is added prior to cutting reconstituted tobacco sheet, rather than to already cut tobacco.

CN108713788 teaches how to mix tobacco powder with propylene glycol, binder, leavening agent, flavoring agent and water to obtain a mixture; the mixture thus obtained is subjected to a rolling treatment to obtain a tobacco sheet, and then the sheet is cut. Thus, in CN108713788, propylene glycol was added prior to cutting the tobacco sheet, rather than to the already cut tobacco.

US2006/0021626 teaches mixing together cellulose, tobacco, a binder and a humectant (e.g. propylene glycol) to obtain a mixture; the mixture thus obtained is used to obtain tobacco sheets, which are then cut. Thus, in US2006/0021626, propylene glycol is added prior to cutting the tobacco sheet, rather than to already cut tobacco.

Furthermore, all prior documents WO 2017/051034, CN108713788 and US2006/0021626 teach the use of reconstituted tobacco only, in particular reconstituted tobacco sheets, for the preparation of heated but non-burning ("HnB") solid cigarette smoking products. In contrast, the process of the present invention provides for the preparation of a heated, non-burning ("HnB") solid smoking product for cigarettes using traditional tobacco shreds of a traditional type, not just reconstituted tobacco.

Furthermore, the selection of various agents/substances for forming the aerosol according to the process teaching of the present invention, in particular propylene glycol (preferred over glycerol or other materials for forming the aerosol), and also provides for the selection of a specific amount, i.e. at least 6%, preferably 10% -21%, of propylene glycol, to be added after the tobacco cut. In particular, the specific choice of propylene glycol is advantageous because propylene glycol has a lower boiling point than glycerol, so that it can evaporate at lower thermal energies during use, thereby generating an aerosol. Furthermore, advantageously, by adding propylene glycol to the cut tobacco before it is dried, i.e. due to the addition of propylene glycol after this cutting step, it is possible to use a conventional cutting machine.

From the above, it is clear that the process according to the invention is particularly advantageous, since the chemical-physical and organoleptic characteristics of the final heated but not burnt (HnB) smoking product (cigarette) thus obtained are very similar to those of other heated but not burnt (HnB) products obtained using reconstituted tobacco alone, however, the process according to the invention is more ecologically sustainable and, moreover, the costs are significantly lower, in particular reduced:

-plant construction and maintenance costs,

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

the cost of additives added in conventional solutions for forming the flakes and obtaining the extrudates.

In particular, when heated but not combusted, the final product obtained according to the process of the present invention produces an aerosol comprising gases and vapors of the inhalable tobacco product, while retaining as much as possible the taste, sensory experience, nicotine delivery profile and traditional characteristics of the smoking product intended for tobacco lighting/combustion (i.e., "lit cigarettes").

Claims

1. An improved process for the preparation of smoking products of the heated but non-combustible type, in particular in the form of cigarettes, characterized in that to tobacco and/or hemp-based cut material is added propylene glycol in a percentage not lower than 6% by weight, calculated on the anhydrous basis of the cut material.

2. The process according to claim 1, characterized in that to the cut tobacco and/or hemp-based material is added propylene glycol in a percentage equal to about 6% to 30% by weight on a dry basis of the cut material.

3. The process according to one or more of the preceding claims, characterized in that to the cut material based on tobacco and/or hemp, propylene glycol is added in an amount equal to about 10% -21% by weight on a water free basis of the cut material.

4. A process according to one or more of the preceding claims, characterized in that said cut material consists only of cut tobacco obtained only from a mixture of natural tobaccos, preferably from at least one mixture of at least one type of natural tobacco.

5. The process according to one or more of the preceding claims, characterized in that said cut material consists of a mixture of natural tobacco and reconstituted tobacco.

6. The process according to one or more of the preceding claims, characterized in that no reconstituted tobacco sheet to be cut is provided for manufacturing and/or using.

7. The process according to one or more of the preceding claims, characterized in that glycerol is also added to said tobacco or hemp-based cut material.

8. The process according to one or more of the preceding claims, characterized in that an additive, preferably a flame retardant additive, is also added to the tobacco or hemp-based cut material.

9. The process according to one or more of the preceding claims, characterized in that said cut material consists of a tobacco sheet obtained by cutting a pre-moistened mixture of tobacco and/or hemp, with a width substantially in the range 0.12-2.5 mm.

10. The process according to one or more of the preceding claims, characterized in that propylene glycol is applied directly to the cut tobacco only.

11. The process according to one or more of the preceding claims, characterized in that the tobacco material to be cut and/or cut is free of any binder and is not added or combined with any binder.

12. The process according to one or more of the preceding claims, characterized in that said cut tobacco material to which said propylene glycol is directly added consists only of tobacco that has been cut into strips after mechanical mixing and moistening.

13. The process according to one or more of the preceding claims, characterized in that propylene glycol, as substance/agent for forming aerosols, is added to said cut material exclusively and exclusively in a percentage by weight equal to about 6% -30%, preferably equal to about 10% -21%, of the cut material on a water-free basis.

14. The process according to one or more of the preceding claims, characterized in that to said cut material the following are added as substances/agents for forming an aerosol:

-glycerol in a lower percentage by weight on a water free basis than propylene glycol.

15. The process according to one or more of the preceding claims, characterized in that it comprises the following steps, wherein:

-obtaining at least one type of tobacco leaves,

preferably by wetting the pre-mixed tobacco leaves with/in water,

-mixing, preferably mechanically mixing, the obtained tobacco leaves,

-cutting the moistened tobacco leaves to obtain cut tobacco,

16. The process according to one or more of the preceding claims, characterized in that during and/or after said wetting step but before said cutting step, propylene glycol and/or glycerol or sorbitol can be added to said tobacco leaves in a percentage by weight of less than about 5% on a tobacco leaf anhydrous basis.

17. Process according to one or more of the preceding claims, characterized by the fact that it also comprises a stage of drying the cut tobacco.

18. A process according to one or more of the preceding claims, characterized in that it comprises a step of packaging the dried shredded tobacco with a covering/wrapping material to obtain a solid smoking product of the heated but non-combustible type.

19. A process according to one or more of the preceding claims, characterized in that it comprises a step of packaging a plurality of smoking products of the heated but not burning type, each of said products being obtained by wrapping a cut tobacco with a covering/wrapping material.

20. A process according to one or more of the preceding claims, characterized in that propylene glycol is added to the shredded tobacco immediately after cutting, in a percentage by weight on a shredded tobacco anhydrous basis equal to about 6% -30%, preferably equal to about 10% -21%.

21. Process according to one or more of the preceding claims, characterized in that propylene glycol is added to the shredded tobacco in a percentage by weight equal to about 6% -30%, preferably equal to about 10% -21%, on a tobacco-free basis, immediately before and/or during and/or immediately after drying the shredded tobacco.

22. Process according to one or more of the preceding claims, characterized in that propylene glycol, in percentages by weight on a tobacco-free basis equal to about 6% to 30%, preferably equal to about 10% to 21%, is added to the tobacco thread immediately before and/or during and/or immediately after said step of packaging the tobacco thread to form a solid smoking product of the heated but not burning type.

23. A process according to one or more of the preceding claims, characterized in that propylene glycol is added to the shredded tobacco in a percentage by weight equal to about 6% -30%, preferably equal to about 10% -21%, on a shredded tobacco anhydrous basis, immediately before and/or during and/or immediately after the packaging step of a plurality of smoking products of the heated but not burnt type obtained by packaging the shredded tobacco.

24. The process according to one or more of the preceding claims, characterized in that said tobacco or hemp-based cut material is of the type used for producing tobacco-burning smoking products.

25. The process according to one or more of the preceding claims, characterized in that liquid propylene glycol, glycerol and/or other additives are added in one or more of the following steps:

immediately after the cutting stage of the tobacco and/or hemp mixture, and/or

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

During the wrapping phase of the cigarettes containing the cut material, and/or

After the step of packaging the cigarettes comprising the cut material, and/or

During the wrapping phase of the cigarette comprising the cut material.

26. Process according to the preceding claim, characterized in that propylene glycol is added in only one of the above-mentioned stages, so that in a single stage it is substantially reached a percentage by weight on a water free basis of the cutting material equal to about 6% to 30%, preferably equal to about 10% to 21%.

27. The process according to claim 25, wherein propylene glycol is added in part in at least two of said stages, such that the final and overall weight percentage of propylene glycol of the cut material in the solid smoking product thus obtained is equal to about 10% -21% on a cut material anhydrous basis.

28. Process according to the preceding claim, characterized in that:

no addition (and thus lack of) propylene glycol to the tobacco prior to cutting,

-adding less than 6% by weight propylene glycol on a cut filler anhydrous basis to the tobacco after cutting the tobacco.

29. Process according to the preceding claim, characterized in that:

-adding to tobacco, preferably moist tobacco, prior to cutting the tobacco, less than 5% by weight, based on the anhydrous basis of the tobacco, of propylene glycol,

-after cutting said tobacco, before cutting, less than 5% by weight on a cut material anhydrous basis of propylene glycol has been added to the tobacco, to which less than 6% by weight on a cut filler anhydrous basis of propylene glycol has been added.

30. Process according to the preceding claim, characterized in that, before cutting the tobacco, less than 5% by weight of glycerol, based on the moisture free basis of the tobacco to be cut, is added to the tobacco, preferably moistening the tobacco.

31. Process according to the preceding claim, characterized in that immediately after the tobacco cutting step, liquid propylene glycol and/or glycerol and/or other additives are added when the absolute humidity of the cut material is in the' OV range of 16-38%.

32. Process according to the preceding claim, characterized in that, immediately after the drying step or the perfuming step, propylene glycol and/or glycerol and/or other additives can be added when the absolute humidity of the cut material is between 10% and 18%.

33. A process according to one or more of the preceding claims, comprising introducing/inserting a capsule containing liquid propylene glycol and/or glycerine and/or other additives into a smoking product during packaging, contacting the tobacco-based and/or hemp-based material, said capsule opening and/or rupturing after being pressed, thereby impregnating the cut material of the cigarette with propylene glycol and/or glycerine and/or other additives.

34. Process according to one or more of the preceding claims, characterized in that, in order to add propylene glycol and/or glycerol and/or other additives to the material that has been cut, at least one of the following steps is carried out:

-depositing the cut material on at least one conveyor belt,

-spraying/sprinkling one or more liquid substances comprising propylene glycol and/or glycerol and/or other additives onto the material deposited on the conveyor belt.

35. The process according to one or more of the preceding claims, characterized in that:

the one or more liquid substances sprayed/sprinkled onto the material deposited on the conveyor belt also comprise water, and

at the end of the spraying/sprinkling phase, the material thus obtained is subjected to a drying step.

36. A process according to one or more of the preceding claims, wherein, for the addition of a liquid comprising propylene glycol and/or glycerol and/or other additives during and/or after the step of packaging of smoking products comprising shredded tobacco material, a liquid dispensing device is used, comprising a plurality of means (4, 11) for applying said liquid, and configured so that each said application means (4, 11) is in a position axially facing a smoking product (7, 14) positioned in a drum (5, 13) of a packaging machine, so that said application means (4, 11) applies said liquid onto the cut material contained in the facing smoking product.

37. Process according to one or more of the preceding claims, characterized in that, for the addition of a liquid comprising propylene glycol and/or glycerol and/or other additives during and/or after the packaging step of a plurality of smoking products comprising cut material, a liquid dosing equipment is used comprising a plurality of means (4, 11) for applying said liquid and configured so that each said application means (4, 11) is in a position axially facing a smoking product (7, 14) positioned in a drum (5, 13) of a cigarette wrapping machine, so that said application means (4, 11) applies said liquid onto the cut material contained in the facing smoking product.

38. The process according to one or more of the preceding claims, characterized in that in the drying step the tobacco material is dried in a heated environment at a temperature of about 30-130 ℃, preferably about 50-90 ℃.

39. Smoking product of the heated but not burnt type, preferably in the form of a cigarette and/or rod, characterized in that it is obtained by a process according to one or more of the preceding claims and comprises at least one portion for generating an aerosol, said portion comprising said shredded tobacco wrapped by or in an outer covering/wrapping material.

40. Smoking product of the heated but not combustible type, preferably in the form of a cigarette and/or rod/rod, comprising at least one portion for generating an aerosol, inside which an outer covering/wrapping material is wrapped, characterized in that said portion for generating an aerosol comprises a cut tobacco to which, after cutting, propylene glycol is added in a percentage by weight, calculated on the anhydrous basis of the cut tobacco, of between about 6% and 30%, preferably equal to between about 10% and 21%.

41. Product according to the preceding claim, characterized in that said portion for generating an aerosol comprises only and exclusively cut tobacco and in that, after cutting, propylene glycol is added to the cut tobacco in a percentage by weight equal to about 6-30%, preferably equal to about 10-21%, based on the anhydrous basis of the cut tobacco.

42. Product according to one or more of the preceding claims, characterized in that said cut filler is obtained by exclusively and exclusively mixing, preferably mechanically mixing, only natural tobacco of the same type or of different types.

43. The product according to one or more of the preceding claims, characterized in that said cut tobacco is obtained from a mixture of moistened flaps of tobacco, the humidity of which is preferably between about 17% and 30%.

44. The product according to one or more of the preceding claims, characterized in that said portion for generating aerosols can comprise reconstituted/homogenized tobacco in addition to said cut tobacco.

45. The product according to one or more of the preceding claims, characterized in that said portion for generating aerosol does not comprise any binder and in addition said shredded tobacco of said portion does not comprise any binder.

46. The product according to one or more of the preceding claims, characterized in that said portion for generating aerosol does not contain cellulose and, in addition, said shredded tobacco of said portion does not contain added cellulose.