Method for making a continuous web

Abstract

A method for making a continuous web (N), comprising a step of mixing a first quantity of liquid with a second quantity of dry product in a kneader (100) thus obtaining a mixture having a moisture content of less than 65%, and a subsequent step of forming a continuous web (N) from the mixture. In particular, the step of forming a continuous web (N) provides performing at least one vertical lamination of the mixture, which creates a foliation of the mixture into two layers which diverge from each other relative to a midplane (M).

Description

[0001] DESCRIPTION

[0002] METHOD FOR MAKING A CONTINUOUS WEB.

[0003] Technical field

[0004] The present invention relates to the field of smoking articles and is directed to a method for making a continuous web.

[0005] Background art

[0006] It is known to make a reconstituted continuous web from a plant-based mixture. The term "plant-based” mixture means a plant-based material (tobacco or non-tobacco) processed by grinding or other similar procedure to modify the particle size thereof so as to promote subsequent mixing treatments thereof. In particular, it is intended that the continuous web is a semifinished product obtained by mixing and processing at least one dry plant component, such as tobacco or non-tobacco (cellulose or cellulose derivatives, rapeseed, hemp, straw or other varieties, hemp, aromatic leaves or others) with a wet component, such as, e.g. water, and one or more additives, according to the generality of the invention.

[0007] In particular, methods are known for making “dough” type mixtures, i.e., with a low percentage of moisture content, which are characterized by the preparation of a mixture obtained from mixing particles of tobacco and / or cellulose with at least one liquid component, such as, e.g. water, where the mixture is portioned into predetermined doses followed by subjecting it to a succession of separate laminating steps to obtain the continuous layer of reconstituted material which is finally dried, obtaining a continuous web. In particular, the lamination is carried out primarily by means of at least one vertical laminating stage and followed by, at least one further subsequent laminating stage.

[0008] Although this technology is well operable for the mentioned type of mixtures, the Applicant has noted that this technology is not completely optimized due to the specific physical-mechanical properties of such a type of mixture (such as, for example, viscosity, elasticity, density, tenacity, expandability, adhesiveness, colloidality, and others) which make the handling thereof complex.

[0009] In particular, the Applicant has found that for a mixture characterized by the presence of a considerable percentage of dry component and a small liquid content, a criticality persists in processing the mixture. Indeed, the handling of the mixture is critical because the laminating rollers are not always capable of effectively processing the mixture itself, compromising the formation of a continuous layer with the desired properties.

[0010] Therefore, in such a context, it is the technical task of the present invention to provide a method for making a continuous web which is free from the drawbacks of the prior art.

[0011] It is therefore the object of the present invention to provide a method for making a continuous web which is capable of obtaining a satisfactory finished product in terms of quality.

[0012] It is a further object of the present invention to provide a method for making a continuous web which is capable of ensuring a correct lamination of the mixture.

[0013] Disclosure of the invention

[0014] Within the scope of the same technical task, it is a further object of the invention to provide a method for making a continuous web which, in order to be implemented on the specific material identified, requires a compact and structurally simplified system.

[0015] The specified technical task and the specified objects are substantially achieved by a method and a system for making a plant-based material web comprising the technical features presented in appended claim 1 and / or in one of the claims dependent thereon, respectively, and / or in the appended description.

[0016] In particular, the Applicant has found that creating a foliation of the mixture in two layers which diverge from each other relative to a midplane (i.e., that derive from a separation of the material) during the laminating step, particularly (but not necessarily) vertical, with an adequate laminating pressure, ensures a uniform distribution of the mixture being fed to the subsequent laminating stage, reducing the probability of irregularities or discontinuities in the structure of the laminated product. Advantageously, the foliation optimizes the processability of the mixture, improving its ability to be modelled and handled during the entire laminating process.

[0017] The technical task specified and the objects specified are also substantially achieved by a method and a system for making a plant-based material web comprising the technical features presented in appended claim 19.

[0018] Indeed, the Applicant has found that, in particular in the case of mixtures characterized by the presence of a considerable percentage of dry component and a reduced moisture content (having a moisture content of less than 65%, in particular comprised between 15% and 50%, preferably comprised between 15% and 40%, even more preferably comprised between 20% and 35%), the mixture leaving at least a first pair of laminating rollers has a discontinuous structure, in particular, flaky. The term "flaky structure" in the present description means a semifinished product broken into a plurality of fragments / discrete elements of irregular shape and having a plate-like structure (i.e., extending substantially on a plane). The division of the material, during the first lamination, into a broken semifinished product allows optimizing the subsequent lamination, improving also the quality of the end product.

[0019] The additional secondary features of the method, already listed with reference to the embodiment with foliation, are equally valid also in this case.

[0020] Further features and advantages of the present invention will become more apparent from the following indicative and thus non-limiting description of one embodiment of a method for making a web according to the invention.

[0021] Brief description of drawings This description will be presented below with reference to the accompanying drawings, provided by way of mere and thus non-limiting indication, in which:

[0022] - Figure 1 shows a diagrammatic view of a preferred exemplary, and therefore non-limiting, embodiment of a system for making a web according to the present invention;

[0023] - Figure 2 shows a first operating portion of the system in Figure 1 ;

[0024] - Figure 3 shows a second operating portion of the system in Figure 1 .

[0025] Detailed description of preferred embodiments of the invention

[0026] The method for making a web is now described in one embodiment thereof, with reference to system 1 used to implement it.

[0027] The web “N” according to the present invention is a plant-based material web. In the present description, the term "plant-based material” means a plant-based material (tobacco or non-tobacco) processed by grinding, or other similar procedure, to modify the particle size thereof so as to promote subsequent mixing treatments thereof. In particular, it is intended that the continuous web is a semi-finished product obtained by mixing and processing at least one dry plant component, such as tobacco or nontobacco (rapeseed, hemp, straw or other varieties, cellulose or cellulose derivatives, hemp, aromatic leaves or others), with a wet component, e.g. water, and one or more additives, according to the generality of the invention.

[0028] According to the present invention, the method provides feeding a first quantity of at least one liquid into a mixing chamber "V" of a kneader 100 and feeding a second quantity of at least one dry fibrous, ground or powdered product, into the mixing chamber "V" of kneader 100.

[0029] The kneader 100 can be of any type, as long as it is capable of mixing the solid and liquid components. Preferably, kneader 100 is configured to operate “in batches”. Preferably, the kneader is configured to operate on mixtures having an overall weight comprised between 4kg and 450 kg, more preferably comprised between 8 kg and 400 kg (end limits obtained by calculating the ranges from an hourly industrial production and from the cycle times).

[0030] As for feeding the first quantity, the term "at least one liquid" means mainly water and preferably at least one additional component, preferably premixed with water. In particular, the additional component comprises one or more of glycerin, nicotine, lactic acid, propylene glycol, dyes, at least one binding agent. In order to feed the first quantity of at least one liquid, system 1 comprises a feed line 110 for the at least one liquid, connected to kneader 100.

[0031] If one or more of the aforementioned additional dry products are included, the feeding line 110 can comprise a plurality of feeding branches 111 , 112, each one dedicated to a particular liquid component.

[0032] The feed line can further comprise an intermediate tank 113, operatively disposed upstream of kneader 100 and connected to kneader 100 by means of a delivery branch 114. The water and additional components are pre-loaded into and pre-dosed in the intermediate tank 113. Preferably, the intermediate tank 113 is provided with mixing means configured to mix the water with the one or more additional components.

[0033] As for feeding the second quantity, the term "at least one dry product" is intended to mean mainly tobacco (in the forms envisaged) and possibly at least one additional dry e.g., fibrous, ground and / or powdered product, preferably in smaller quantities. In particular, the additional dry product can comprise cellulose or cellulose derivatives, rapeseed, hemp, straw or other varieties, hemp, cocoa, aromatic leaves or others.

[0034] According to an alternative, as for feeding the second quantity, the term "at least one dry product" is intended to mean mainly cellulose (in the forms envisaged) and possibly at least one additional dry e.g., fibrous, ground and / or powdered product, preferably in smaller quantities. In particular, the additional dry product can comprise tobacco or derivatives, rapeseed, hemp, straw or other varieties, hemp, cocoa, aromatic leaves or others.

[0035] According to an embodiment, as mentioned above, the at least one dry product can be tobacco-based, i.e., the mixture can comprise a tobacco content higher than 50% by weight, for example, comprised between 50% and 85%, preferably comprised between 55% and 80%. According to this embodiment, the mixture can comprise a cellulose content in fibrous and / or ground or powder form comprised between 0% and 15%, even more preferably between 2% and 8%.

[0036] According to an embodiment, as mentioned above, the at least one dry product can be cellulose-based. In this case, the mixture can comprise a cellulose content higher than 40%, for example, comprised between 50% and 85%, even more preferably comprised between 50% and 60%.

[0037] In order to feed the second quantity of at least one dry product, the system 1 comprises a feed line 120 for the at least one dry product, which is connected to kneader 100.

[0038] If one or more additional dry products are included, the feeding line 120 can comprise a plurality of feeding branches 121 , 122, each dedicated to a particular dry product. Alternatively, in the event of two or more dry products, they can be premixed outside kneader 100 and then be fed to it by means of the same feed branch 121 , 122.

[0039] The feed line 120 can further comprise an intermediate tank 123, operatively disposed upstream of kneader 100 and connected to kneader 100 by means of a delivery branch 124, where the dry products are pre- loaded and pre-dosed.

[0040] The method thus includes a step of mixing the second quantity of dry product with the first quantity of liquid in the kneader 100, obtaining a mixture with humidity content lower than 65%. In particular, the mixture obtained has a moisture content (by weight) comprised between 15% and 50%, preferably between 15% and 40%, even more preferably comprised between 20% and 35%r It is clear that the second quantity of dry product and the first quantity of a liquid can be fed into the kneader 100 simultaneously, possibly after premixing the second quantity of dry product outside the kneader 100.

[0041] Preferably, the mixture generally has a quantity of glycerin (by weight) comprised between 2% and 40%.

[0042] In the case where the at least one dry product is a tobacco-based product, as mentioned above, the quantity of glycerin in the mixture can be comprised between 2% and 25% and preferably it is comprised between 15% and 20%.

[0043] In the case where the at least one dry product is a cellulose-based product, as mentioned above, the quantity of glycerin present in the mixture preferably is comprised between 30% and 40%.

[0044] According to an aspect, it has been found that the mixture produced by mixing has a sandy and / or grainy texture, specifically with an average particle size comprised between 1 and 10 mm.

[0045] Once the kneading step is finished, the method includes forming the aforesaid continuous web "N" from the mixture itself, by lamination.

[0046] The step of forming the web “N” firstly provides performing at least one lamination of the mixture by means of a laminating unit 2 equipped with at least one pair of rollers 201 , 202, 301 , 302.

[0047] According to a particularly advantageous embodiment, the laminating unit 2 is a vertical laminating unit.

[0048] According to an alternative embodiment, the laminating unit 2 is a horizontal laminating unit.

[0049] The Applicant has found that the technical effect of foliation with uniform distribution of the mixture is obtainable in both configurations, albeit being more pronounced in the case of vertical lamination.

[0050] The mixture leaving the laminating unit 2 is fed to a secondary laminating unit, for example, of the horizontal type (as better specified in the following disclosure). According to the preferred embodiment, the mixture leaving the laminating unit 2 is released onto a support 4, preferably a conveyor, configured to convey the mixture leaving the laminating unit 2 to a secondary laminating unit 3, for example, horizontal, where a secondary lamination is performed, subsequently obtaining a continuous layer of material. Alternatively, the mixture leaving the laminating unit 2 can be fed directly into (for example, by gravity) a secondary laminating unit, for example, vertical, where subsequently a secondary lamination of the mixture leaving the laminating unit 2 is performed, subsequently obtaining a continuous layer of material.

[0051] Finally, the continuous layer is dried, obtaining the aforesaid continuous web “N”.

[0052] Structurally, according to the preferred embodiment, the laminating unit 2 comprises at least a first vertical laminating stage 200 comprising a respective pair of laminating rollers 201 , 202.

[0053] Preferably, the laminating unit 2 comprises at least a first vertical laminating stage 200 and one or more subsequent vertical laminating stages 300, where each laminating stage 200, 300 comprises a respective pair of laminating rollers 201 , 202, 301 , 302. In such embodiments, the laminated mixture from the first laminating stage 200 is fed by gravity or by transport to the subsequent laminating stages 300. One or more scraping tools 400, such as blades, can also be included, operatively connected to the rollers of each laminating stage 200, 300, which blades are configured to carry out the aforesaid scraping.

[0054] According to a particularly advantageous embodiment, the laminating unit 2 comprises a first laminating stage 200 and a second laminating station 300, both vertical. However, according to the generality of the invention, as will be increasingly apparent from the continuation of the present invention, three or more vertical laminating stages may also be employed.

[0055] According to an aspect, it was found that in the event of mixtures having physical features according to that explained above (in particular, with reference to the percentages of moisture content and fraction of dry product), the mixture leaving at least the first pair of rollers 201 , 202 has a discontinuous structure, in particular, flaky. The term "flaky structure" in the present description means a semifinished product broken into a plurality of fragments / discrete elements of irregular shape and having a plate-like structure (i.e., extending substantially on a plane).

[0056] Preferably, the flakes have an average thickness comprised between 0.2 mm and 3 mm.

[0057] According to an example, should the laminating unit 2 have only one vertical laminating stage, the mixture leaving at least the first vertical laminating stage 200 has a flaky structure. According to such an example, therefore, the mixture leaving the laminating unit 2 has a flaky structure.

[0058] According to a further example, should the laminating unit 2 have a first laminating stage 200 and a second laminating stage 300, the mixture leaving at least the first laminating stage 200 has a flaky structure, while the second laminating stage 300 can be configured to collect such flakes and re-laminate them, also in this case obtaining a mixture having a flaky structure. According to such an example, therefore, the mixture leaving the laminating unit 2 has a flaky structure.

[0059] According to a further example, should the laminating unit 2 have a first laminating stage 200 and a second laminating stage 300, the mixture leaving at least the first laminating stage 200 has a flaky structure, while the second laminating stage 300 can be configured to collect such flakes and re-laminate them, obtaining in this case a mixture having a continuous layer structure. In other words, according to such an example, the second laminating stage 300 is configured to obtain a continuous layer leaving the laminating unit 2.

[0060] According to a further example, should the laminating unit 2 have a first laminating stage 200, a second laminating stage 300 and a third secondary laminating stage, the mixture leaving at least the first laminating stage 200 has a continuous layer structure, the mixture leaving the at least a second laminating stage 300 has a flaky structure, the secondary laminating stage can be configured to collect such flakes and re-laminate them, obtaining a continuous layer.

[0061] According to further examples with three or more laminating stages, combinations of the features described above can occur so as to obtain mixtures with a flaky structure, vertical laminating stages that collect and relaminate the flakes and / or vertical laminating stages configured to obtain, leaving the laminating unit 2, a mixture with a flaky structure or a mixture with a continuous layer structure.

[0062] According to an aspect of the present invention, the at least one vertical lamination of the mixture creates, on leaving at least one pair of rollers 201 , 202, 301 , 302, a foliation of the mixture into two layers that diverge from each other with respect to a midplane “M”, as shown in Figure 2. In other words, independently of the fact that the mixture is formed according to a flaky or continuous layer structure, the mixture is laminated vertically by at least one pair of rollers 201 , 202, 301 , 302 so that a foliated layer into two parts in obtained on leaving, which separate into directions opposite to the midplane “M”.

[0063] Preferably, the foliation of the mixture is preferably performed by operating the rollers 201 , 202, 301 , 302 of the same pair of rollers, substantially at the same peripheral speed. In other words, the rollers 201 , 202, 301 , 302 of at least one pair of laminating rollers operate (i.e., they are activated) at a substantially equivalent peripheral speed, preferably at the same peripheral speed, obtaining the aforesaid foliation of the mixture.

[0064] Preferably, the foliation is operated on at least the first laminating stage 200. Preferably, when present, the foliation is operated also on the second laminating stage 300. Even more preferably, should there be two or more vertical laminating stages, the foliation is operated on each vertical laminating stage so as to optimize the process.

[0065] The foliation process can therefore be implemented in a versatile manner, operating both when the mixture takes on the flaky structure, as exemplified above, and when the mixture is in the form of a continuous layer. Such flexibility is adapted to the different structures of the laminating unit 2 and the different combinations of laminating stages 200, 300 thereof including both those with a single vertical laminating stage and those with two or more stages that collect and re-laminate the flakes.

[0066] Advantageously, the foliation contributes to ensuring a uniform distribution of the mixture, reducing the probability of irregularities or discontinuities in the structure of the laminated product. This process optimizes the efficiency of the subsequent horizontal laminating unit 3, allowing a more uniform and controlled lamination.

[0067] Advantageously, the foliation optimizes the processability of the mixture, improving the ability thereof to be modelled and handled during the subsequent laminating process, for example, horizontal. This facilitates the formation of laminated semi-finished products with desired features, such as thin and consistent layers, contributing overall to an improvement of the quality of the finished product.

[0068] Moreover, should the foliation be performed when there is a flaky structure, advantageously the processability of the mixture is further improved so as to obtain an optimal finished product, and the feeding to the subsequent laminating unit 3, for example horizontal, is further improved.

[0069] Downstream of the vertical lamination 2, the aforesaid horizontal lamination is then preferably carried out so as to obtain a continuous layer.

[0070] To this end, the horizontal lamination unit 3 comprises at least one horizontal lamination stage 500, provided with a respective pair of rollers 501 , 502. Preferably, the horizontal laminating unit 3 is a multistage laminating unit having two or more stages 500, each comprising a respective pair of rollers 501 , 502 configured to achieve a controlled reduction of the thickness of the continuous layer until having a calibrated thickness value. To this end, the horizontal laminating unit 3 comprises a plurality of pairs of horizontal rollers 501 , 502 arranged in series, which pairs of rollers 501 , 502 delimit an increasingly narrow passage therebetween to gradually reduce the thickness of the continuous layer. According to an aspect of the present invention, as shown in Figure 3, the horizontal laminating unit 3 comprises at least one horizontal laminating stage 500 comprising a respective pair of opposite rollers 501 , 502 configured to mix the mixture in a niche 503 defined between the two rollers 501 , 502, and next compressing the mixture in the through slot between the two rollers, so as to obtain the continuous layer. Preferably, each horizontal laminating stage 500 carries out the aforesaid step of mixing the mixture in the respective niche 503.

[0071] In other words, the two opposite rollers 501 , 502 of such an at least one horizontal laminating stage 500 define, immediately upstream thereof, an accumulation niche 503 of the mixture which tends to form a mass having the shape of niche 503 itself, which is deformed, mixed and / or blended with respect to the flow reaching such rollers 501 , 502. The mixture material is then progressively retrieved by the rotation of the rollers 501 , 502, and compressed up to obtaining the mentioned continuous layer. The horizontal laminating stage 500 thus performed therefore re-mixes and completes the hydration of the dry particles in the mixture. In other words, a step of accumulating the material in the niche 503 defined between the surfaces of the two rollers 501 , 502 is carried out, and a step of compression applied between the two rollers 501 , 502 to form the continuous layer at a constant thickness is carried out. With this operation, the mixture material is subjected to a re-mixing and / or redistribution step in the accumulation area (niche 503) which, in combination with the subsequent compression between the two rollers 501 , 502 and with the specific liquid content of the material itself, further kneads the mixture. Therefore, as the number of horizontal laminating stages 500 increases, it is possible to increasingly handle the mixture, improving the physical-mechanical properties thereof and the hydration of the dry particles.

[0072] Advantageously therefore, in addition to forming the continuous layer, the horizontal lamination thus performed plays a crucial role in mixing the mixture through the accumulation niche 503 at the entry of the respective opposite rollers 501 , 502. This action contributes to improving the integration of the ingredients, ensuring a more uniform distribution of any fillers or additives, and providing increased control over the consistency of the mixture. This process contributes therefore to improving the quality of the finished product, ensuring a more homogenous continuous layer and facilitating the processability of the mixture during the subsequent production steps.

[0073] Moreover, these operations advantageously allow energy efficiency to be optimized and time to be saved in the entire production process. By virtue of the mixing operated in the horizontal laminating unit, the upstream kneader 100 may require less time and energy to complete the preparation step.

[0074] According to an embodiment, the horizontal lamination (and correspondingly, the horizontal laminating unit) may be absent, and only the vertical lamination (for example, several vertical lamination stages, as described above) may be present.

[0075] According to a different embodiment (not shown), following one or more vertical laminating stages, there can be a plurality of rollers disposed tangentially to one another to define a laminating and processing path for forming the layer of material. Said layers obtained from the foliation of the mixture may be fed (for example, by feeding from the top, for example, by feeding by gravity or transport) between the first pair of rollers of the laminating and processing path, which therefore can transit along the path, obtaining the continuous layer. In particular, the flakes for forming the continuous layer can be fed (for example, fed from the top, for example, fed by gravity or transport) between the first pair of rollers of the laminating and processing path. Once the continuous layer is formed, the method then comprises the aforesaid drying step to obtain a dried continuous web “N”. To this end, the system can comprise a drying device 600.

[0076] According to a possible embodiment, the at least one dry product comprises metallic particles and / or powders. The metallic particles and / or powders are therefore fed into the kneader 100, for example, by means of the feed line 120 described above. To this end, the feed line 120 can comprise a dedicated feed branch 121 , 122. Alternatively, the metallic particles and / or powders can be premixed outside the kneader 100, for example, with another dry product (e.g. tobacco or cellulose) and be fed into the kneader 100 by means of the same feed branch 121 , 122.

[0077] According to the aforementioned embodiment, the mixture formed comprises a content of said metallic particles and / or powders comprised between 3% and 30% by weight, preferably comprised between 5% and 20%, and more preferably equal to about 8%.

[0078] Advantageously, the foliation of the mixture into two mutually diverging layers in this embodiment allows an optimal mixing of the metallic powders and / or particles with the remaining part of the mixture. Indeed, when the mixture is being formed by means of a conventional type of lamination, an optimal distribution of such metallic powders and / or particles cannot be ensured. Instead, the foliation of the mixture containing such metallic powders and / or particles and a secondary lamination allows a further mixing stage of the mixture, where the metallic powders and / or particles are better distributed against a laminating process of the prior art. Such an advantage becomes even more apparent in the case of the formation of flakes, which can be easily re-laminated.

[0079] It is understood that the metallic particles and / or powders can be provided in addition to another dry product (e.g. tobacco or cellulose).

[0080] The metallic particles and / or powders are provided to promote the thermal conductivity of the end product, which is intended for the sector of smoking articles.

[0081] It is understood that in this particular embodiment, the mixture does not comprise other conductive particles capable of promoting thermal conductivity apart from the aforementioned metallic particles and / or powders. In other words, the mixture does not comprise other particles such as graphite, carbon and its derivatives and / or minerals capable of promoting thermal conductivity. The present invention achieves the preset objects, eliminating the drawbacks of the prior art. The division of the material, during the lamination (preferably but not necessarily vertical), into two mutually diverging layers allows an optimization of the subsequent lamination (for example, horizontal), thus also improving the quality of the final product.

Claims

CLAIMS1 . A method for making a continuous web, comprising the following steps:- a step of mixing a first quantity of a liquid with a second quantity of at least one dry product in a kneader (100) to obtain a mixture, where said mixture has a moisture content of less than 65%;- a subsequent step of forming a continuous web (N) from said mixture, wherein said step of forming a continuous web (N) comprises the following sub-steps:- performing at least one lamination on the mixture by means of a laminating unit (2) having at least one pair of rollers (201 , 202, 301 , 302); wherein said lamination of the mixture produces, on leaving at least one pair of rollers (201 , 202, 301 , 302), a foliation of the mixture into two layers which diverge from each other relative to a midplane (M);- feeding said layers, obtained by the foliation of the mixture from the laminating unit (2), to a secondary laminating unit (3);- performing at least one secondary lamination on said layers by means of said secondary laminating unit (3), preferably horizontal, to obtain one continuous layer;- drying the continuous layer to obtain the continuous web (N).

2. A method according to claim 1 , wherein said step of performing at least one lamination is performed by means of a vertical laminating unit (2).

3. The method according to claim 1 , wherein said step of performing at least one lamination is performed by means of a horizontal laminating unit (2).

4. The method according to any one of the preceding claims, wherein the mixture produced by the step of mixing has a sandy and / or grainy texture, preferably with a particle size comprised between 1 mm and 10 mm.

5. The method according to any one of the preceding claims, wherein the rollers of at least one pair of laminating rollers (201 , 202, 301 , 302) operate at a substantially equivalent peripheral speed, preferably at the same peripheral speed, thus obtaining said foliation of the mixture.

6. The method according to any one of the preceding claims, wherein saidfoliation of the mixture is carried out when the mixture has a flaky structure.

7. The method according to any one of the preceding claims, wherein the layers obtained by the foliation of the mixture leaving the laminating unit (2) have a flaky structure.

8. The method according to any one of the preceding claims, wherein said laminating unit (2) comprises a first laminating stage (200), followed by one or more laminating stages (300), each stage comprising a pair of rollers (201 , 202, 301 , 302), and wherein the mixture leaving the first laminating stage (200) has a flaky structure.

9. The method according to claim 8, wherein the mixture leaving the last laminating stage (300) and released onto the support has a flaky structure.

10. The method according to claim 8, wherein the mixture leaving the last laminating stage (300) has a continuous layer structure.

11. The method according to any one of claims 8 to 10, wherein said foliation is performed on at least the first laminating stage (200), preferably also on the second laminating stage (300) and, more preferably, on each laminating stage.

12. The method according to claim 7 or 8, wherein said flakes have an average thickness comprised between 0.2 mm and 3 mm.

13. The method according to any one of the preceding claims, wherein said secondary laminating unit is a horizontal laminating unit (3) and comprises at least one horizontal laminating stage (500) comprising a respective pair of opposite rollers (501 , 502) configured to mix, in at least one stage of the horizontal laminating unit (500), the mixture in an accumulation niche (503) defined between the two rollers (501 , 502), followed by a step of compressing the mixture in the through slot between the two rollers (501 , 502) so as to make the continuous layer.

14. The method according to claim 13, wherein said horizontal laminating unit (3) comprises two or more horizontal laminating stages (500) configured to reduce the thickness of the continuous web in controlled manner until reaching a calibrated thickness value.

15. The method according to any one of claims 1 to 12, wherein said secondary laminating unit (3) comprises a plurality of rollers disposed tangent to each other to define between them a laminating and processing path for forming the continuous layer.

16. The method according to any one of the preceding claims, wherein said mixture has a moisture content comprised between 15% and 40% by weight, preferably comprised between 25% and 35% by weight.

17. The method according to any one of the preceding claims, wherein said mixture comprises a tobacco content greater than 50%, preferably comprised between 50% and 85%, more preferably comprised between 55% and 80%.

18. The method according to any one of claims 1 to 15, wherein said mixture comprises a cellulose content in fibrous and / or ground or powder form greater than 40% by weight, preferably comprised between 50% and 80% and, still more preferably, comprised between 50% and 60%.

19. The method according to any one of the preceding claims, wherein said at least one dry product comprises metallic particles and / or powders, in particular said mixture comprising a content of said metallic particles and / or powders comprised between 3% and 30%.

20. A method for making a continuous web, comprising the following steps:- a step of mixing a first quantity of a liquid with a second quantity of at least one dry product in a kneader (100) to obtain a mixture, where said mixture has a moisture content of less than 65%;- a subsequent step of forming a continuous web (N) from said mixture, wherein said step of forming a continuous web (N) comprises the following sub-steps:- performing at least one lamination of the mixture by means of a laminating unit (2) having at least one pair of rollers (201 , 202, 301 , 302); wherein said at least one lamination of the mixture produces, on leaving at least one pair of rollers (201 , 202, 301 , 302), a mixture having a discontinuous structure, in particular, flaky;- feeding said mixture having a discontinuous structure, in particular flaky, to a secondary laminating unit (3);- performing at least one secondary lamination on said mixture having a discontinuous structure, in particular flaky, by means of said secondary laminating unit (3), preferably horizontal, thus obtaining a continuous layer;- drying the continuous layer to obtain the continuous web (N).

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