WO2016050873A1

WO2016050873A1 - Corrugated reconstituted tobacco sheet

Info

Publication number: WO2016050873A1
Application number: PCT/EP2015/072615
Authority: WO
Inventors: Robert Emmett
Original assignee: Philip Morris Products S.A.
Priority date: 2014-09-30
Filing date: 2015-09-30
Publication date: 2016-04-07

Abstract

A corrugated tobacco sheet (1) is formed by shaping into a corrugated configuration a web (2) of reconstituted tobacco, the web (2) comprising a plurality of flutes (4) and having a first side and a second side. In some embodiments, a first liner (3) is adhered to the first side of the corrugated web (2). The first liner (3) is also formed from a web of reconstituted tobacco. The corrugated tobacco sheet (1) may be used for the manufacture of a tobacco product, such as tobacco cut filler.

Description

CORRUGATED RECONSTITUTED TOBACCO SHEET

The present invention relates to a novel reconstituted tobacco sheet, related manufacturing methods, and uses thereof. In particular, the reconstituted tobacco sheet according to the present invention finds particular application in the manufacture of tobacco cut filler for smoking articles.

There are several known methods for making reconstituted tobacco sheet. These several known methods may include processing tobacco material such as tobacco stems, tobacco stalks, leaf scraps and tobacco dust, which are produced during the manufacturing processes of tobacco products. Such manufacturing processes where the tobacco material may derive include stemming, aging, blending, cutting, drying, cooling, screening, sieving, shaping or packaging operations.

One of the known methods is to ground tobacco stems to a fine powder and then mix the tobacco stems with tobacco dust, guar gum, and water to form an aqueous slurry. This aqueous slurry may be then cast and dried to form a reconstituted tobacco sheet. However, this type of reconstituted tobacco sheet has a low tensile strength. In order to improve this characteristic of the reconstituted tobacco sheet, a non-tobacco cellulose, for example in the form of wood cellulose fibres, is usually added to the slurry as a binder. But, the presence of a non-tobacco ingredient is generally undesirable due to the increase in cost and negative impact on flavour attributed to this ingredient.

In other known methods, tobacco materials are mixed in an agitated tank with water to obtain a pulp. The soaking and mixing of the tobacco in the tank with water causes the water soluble components of the tobacco to dissolve into the liquid, creating a tobacco-flavoured liquid or tobacco juice. This tobacco-flavoured liquid subsequently needs to be separated from the non- soluble portion of the tobacco before further processing. By way of example, the pulp may be compressed or processed using a centrifuge to remove the tobacco-flavoured liquid containing the water-soluble components. The non-water-soluble portion then subsequently undergoes a paper-making process (for example, using a Fourdrinier machine) to form a base web. As is known, a Fourdrinier machine typically includes a forming section, a press section and a drying section. In the forming section, which comprises a plastic fabric mesh conveyor belt often referred to as a "wire" as it was once woven from bronze, the pulp is drained to create a continuous paper web. Subsequently, this wet web is fed onwards to the press section, where the excess water is squeezed out of the web. Finally, the pressed web is conveyed on through a heated drying section. The tobacco-flavoured liquid is also subjected to further processing using an evaporation operation to form a concentrated liquor, which may be added back to the base web in order to at least partly restore flavour to the base web that would otherwise be lost.

In view of subsequent operations in the manufacture of tobacco products, such as smoking articles, from reconstituted tobacco, mechanical properties, such as resilience and tensile strength, of the web are important parameters. Further, in view of the typical use of reconstituted tobacco as a constituent of tobacco cut filler, filling power is another key parameter of a reconstituted tobacco web.

An alternative use of reconstituted tobacco in a smoking article is known from WO 2009/037304, which discloses a smoking article comprising a patch of a material that allows a more free passage of smoke than does the tobacco of the smoking article. The patch may, for example, be arranged underneath the outer wrapper, and may be formed from any material having the appropriate combustion and compositional properties for inclusion in a smoking article and providing the required low-resistance passage for smoke propagation. This provides a preferential low resistance path through the smoking article for the smoke, such that the smoke is delivered more efficiently to the consumer. At the same time, the provision of an open- structured material in the smoking article is meant to increase the static burn rate of the smoking article.

According to WO 2009/037304, suitable materials for the patch include fibrous sheet materials having a sufficiently open structure, such as a cellulosic sheet material. In an embodiment, the patch may comprise corrugated material, such as corrugated paper or cardboard. By arranging the corrugations or ridges/troughs in the material to run lengthwise along the tobacco rod, a plurality of parallel longitudinal open passages are provided around the circumference of the tobacco rod.

As an alternative, a tobacco-containing sheet material, such as a web of reconstituted tobacco may be used, the web having a structure that is inherently suitable for providing low resistance to the flow of smoke. Thus, WO 2009/037304 teaches using reconstituted tobacco as such, not quite as a component of the cut filler forming the tobacco rod of a smoking article, but rather as a further structural element of the smoking article that is either positioned over the tobacco rod before circumscribing the rod with paper wrapper, or adhered to an inner surface of the paper wrapper before winding the paper wrapper around the rod.

It would be desirable to provide an improved reconstituted tobacco web material that displays increased resilience and filling power, particularly in view of its use as a constituent of tobacco cut filler for the manufacture of tobacco rods of smoking articles. Further, it would be desirable to provide one such reconstituted tobacco web material that is also easy to manufacture and that can promptly and conveniently be employed as such in the manufacture of tobacco products, for example as a constituent of tobacco cut filler.

Thus, according to an aspect of the present invention, there is provided a corrugated tobacco sheet comprising a corrugated medium comprising a plurality of flutes and having a first and a second side; and at least one liner. A first liner adheres to the first side of the corrugated medium and the corrugated medium and the liner are formed from a web of reconstituted tobacco. According to a further aspect of the present invention, there is provided a corrugated tobacco sheet comprising a corrugated medium comprising a plurality of flutes and having a first and a second side, the corrugated medium being formed from a web of reconstituted tobacco.

According to another aspect of the present invention, there is provided a tobacco cut filler comprising portions of one such corrugated tobacco sheet, the portions having a mean cut width from about 0.7 millimetres to about 1 .5 millimetres.

According to a further aspect of the present invention, there is provided a tobacco product comprising one such corrugated tobacco cut filler.

According to one further aspect of the present invention, there is provided a method of manufacturing a corrugated tobacco web, the method comprising providing a first web of reconstituted tobacco; and shaping the first web of reconstituted tobacco into a corrugated configuration with a plurality of flutes to form a corrugated medium having a first side and a second side.

It will be appreciated that any features described with reference to one aspect of the present invention are equally applicable to any other aspect of the invention.

Throughout this specification, the expression "web of reconstituted tobacco sheet" is used to refer to a web of substantially uniform thickness that may be produced by the rolling or casting of an aqueous slurry or pulp formed from tobacco by-products such as tobacco stems, tobacco stalks, leaf scraps, and tobacco dust produced during the manufacturing process, for example by one of the methods known in the art described above.

The term "corrugated" is used throughout the present specification to describe a web material, such as a web or sheet of reconstituted tobacco, that has been shaped into folds or parallel and alternating ridges and grooves.

In the present specification, with reference to a corrugated configuration of at least a portion of a reconstituted tobacco web or sheet, the term "flute height" shall be construed as identifying the vertical distance measured from trough to peak in a flute. By way of non limiting example, reference may be made to a sine wave flute shape. In this case, the term "flute height" shall identify a distance equalling twice the amplitude of the sine function. In other words, it is twice the peak deviation of the sine wave function from zero.

In the context of the present specification, with reference to a corrugated configuration of at least a portion of a reconstituted tobacco web or sheet, the term "flute pitch" shall be construed as identifying the horizontal distance measured between adjacent flute troughs. By way of non limiting example, reference may be made to a sine wave flute shape. In this case, the term "flute pitch" shall substantially identify the distance between consecutive maxima of the sine wave function.

The terms "tobacco product" or "tobacco products" are used throughout this specification to refer to both combustible smoking articles and to smoking articles in which an aerosol forming substrate, such as tobacco, is heated rather than combusted. Combustible smoking articles, such as cigarettes, generally comprise shredded tobacco (usually in cut filler form) surrounded by a paper wrapper forming a tobacco rod. The shredded tobacco can be a single type of tobacco or a blend of two or more types of tobacco. A cigarette is employed by a consumer by lighting one end thereof and burning the shredded tobacco rod. The consumer then receives mainstream smoke by drawing on the opposite end (mouth end or filter end) of the cigarette. In heated smoking articles, the aerosol is generated by heating the aerosol forming substrate. Known heated smoking articles include, for example, smoking articles in which an aerosol is generated by electrical heating or by the transfer of heat from a combustible fuel element or heat source to an aerosol forming substrate. During smoking, volatile compounds are released from the aerosol forming substrate by heat transfer from the heat source and entrained in air drawn through the smoking article. As the released compounds cool, they condense to form an aerosol that is inhaled by the consumer. Also known are smoking articles in which a nicotine-containing aerosol is generated from a tobacco material, tobacco extract, or other nicotine source, without combustion, and in some cases without heating, for example through a chemical reaction.

By "filling power" of tobacco cut filler, reference is made throughout this specification to the ability of the tobacco cut filler to form a firm tobacco rod with given moisture content. A high filling power indicates that a lower weight of tobacco is required to produce a tobacco rod than is required with a tobacco of lower filling power.

In contrast to what happens with the crimping of reconstituted tobacco webs for the formation of an aerosol generating substrate for use in heated smoking articles, in the manufacture of a corrugated sheet according to the invention, a material is obtained with a much more significant percentage of voids. Therefore, the overall density of the corrugated sheet is much lower. This advantageously results in an improved filling power, which makes the sheet of the invention particularly suitable for the manufacture of cut filler for smoking articles.

In a preferred embodiment, the corrugated tobacco web of the invention is coupled with at least one substantially flat tobacco web. Thus, the overall mechanical strength and resilience of the sheet is increased, with respect to existing reconstituted tobacco sheets, whilst preserving a satisfactory level of flexibility. Thus, the resulting corrugated tobacco sheet can conveniently be formed into a roll, for example for ease of shipping and transporting. In two-sided embodiments of the corrugated tobacco sheet, wherein two liners are respectively adhered on opposite sides of a fluted tobacco medium, resilience can be further increased. Significant rigidity levels may be achieved, which may be desirable in view of certain mechanical operation that the resulting corrugate tobacco sheet may be subjected to, for example in the manufacturing of smoking articles.

Advantageously, the corrugated tobacco sheet of the present invention may be manufactured from a conventional reconstituted tobacco web using manufacturing equipment known from the cardboard industry. Further, different types of reconstituted tobacco webs can be used at once, such as reconstituted leaf web and cast leaf web obtained from different manufacturing methods and therefore having different characteristics. By suitably blending the different types of reconstituted tobacco webs, flavour characteristics can also be advantageously tailored. Thus, a product that is improved from a mechanical viewpoint and that also satisfies specific taste requirements may conveniently be manufactured.

Further to tobacco material, the reconstituted tobacco webs may comprise one or more binders, such as guar gum, or a flavourant composition, or a combination of the two. Such flavourant composition might include particles of a sorbent or cellulosic material impregnated with liquid flavourant or particulate material such as herbaceous material, or any combination thereof. Flavourant materials include, but are not limited to, materials that contain natural or synthetic menthol, peppermint, spearmint, coffee, tea, spices (such as cinnamon, clove and ginger), cocoa, vanilla, fruit flavours, chocolate, eucalyptus, geranium, eugenol, agave, juniper, anethole and linalool. In addition, flavourant materials may include essential oils, or a mixture of one or more essential oils. An "essential oil" is an oil having the characteristic odour and flavour of the plant from which it is obtained. Suitable essential oils include, but are not limited to, eugenol, peppermint oil and spearmint oil. In many embodiments the flavourant material comprises menthol, eugenol, or a combination of menthol and eugenol. The term "herbaceous material" is used to denote material from an herbaceous plant. An "herbaceous plant" is an aromatic plant, the leaves or other parts of which are used for medicinal, culinary or aromatic purposes and are capable of releasing flavour into smoke produced by a smoking article. Herbaceous material includes herb leaf or other herbaceous material from herbaceous plants including, but not limited to, mints, such as peppermint and spearmint, lemon balm, basil, cinnamon, lemon basil, chive, coriander, lavender, sage, tea, thyme and carvi. The term "mints" is used to refer to plants of the genus Mentha. Suitable types of mint leaf may be taken from plant varieties including but not limited to Mentha piperita, Mentha arvensis, Mentha niliaca, Mentha citrata, Mentha spicata, Mentha spicata crispa, Mentha cordifolia, Mentha longifolia, Mentha pulegium, Mentha suaveolens, and Mentha suaveolens variegata. In some embodiments, flavourant material can include tobacco material.

In corrugated webs of reconstituted tobacco according to the present invention, a web of reconstituted tobacco sheet is shaped into a corrugated configuration and comprises a plurality of flutes. One such corrugated web comprises a first side and a second side.

In a preferred embodiment, the web preferably comprises at least one liner formed from a web of reconstituted tobacco. A first liner adheres to the first side of the corrugated medium.

By way of example, the first liner may be adhered to the corrugated web by means of a binder, such as guar gum or any other suitable binder. Other suitable binder materials may include binders that are compatible with use in the manufacturing of a smoking article. The corrugated web and the liner are formed from webs of reconstituted tobacco. Preferably, each of the medium and liners substantially consist of reconstituted tobacco.

In some embodiments, both the corrugated web and the liner are formed from webs of reconstituted tobacco of the same type, for example they are both formed from webs of cast leaf reconstituted tobacco. Thus, certain mechanical properties, such as the resilience of the sheet, can be maximized. In other preferred embodiments, the corrugated medium and the liner are formed from webs of reconstituted tobacco comprising different types of reconstituted tobacco, such as for example reconstituted leaf and cast leaf. This advantageously makes it possible to enhance the aromatic characteristics of the product.

Preferably, the web further comprises a second liner formed from a web of reconstituted tobacco. The second web adheres to the second side of the corrugated web.

Preferably, the corrugated web and the liner are formed from webs of reconstituted tobacco having a thickness of at least about 0.1 millimetres. More preferably, the corrugated web and the liner are formed from webs of reconstituted tobacco having a thickness of at least about 0.12 millimetres. In addition, or as an alternative, the corrugated web and the liner are preferably formed from webs of reconstituted tobacco having a thickness of less than about 0.3 millimetres. More preferably, the corrugated web and the liner are preferably formed from webs of reconstituted tobacco having a thickness of less than about 0.2 millimetres. In some preferred embodiments, the corrugated web and the liner are preferably formed from webs of reconstituted tobacco having a thickness from about 0.1 millimetres to about 0.3 millimetres. By way of example, the corrugated web and the liner may be formed from webs of reconstituted tobacco having a thickness of about 0.15 millimetres.

In other embodiments, at least one of the corrugated web and the at least one liner is formed from a web of reconstituted tobacco different from the web of reconstituted tobacco from which the other constituents of the corrugated tobacco sheet are formed. In other words, at least one of the corrugated web and the at least one liner is formed from a web of reconstituted tobacco obtained by a manufacturing method different from the manufacturing method by which the web from which the other constituents of the web are formed was obtained. Thus, a greater adjustability of the resulting product, in terms of both mechanical properties and taste characteristics is advantageously achieved.

Preferably, the flutes of the corrugated medium have a height of at least about 0.1 millimetres. More preferably, the flutes of the corrugated medium have a height of at least about 1 millimetres. In addition, or as an alternative, the flutes of the corrugated medium have a height of less than about 5 millimetres. Preferably, the flutes of the corrugated medium have a height of less than about 4 millimetres. In some preferred embodiments, the flutes of the corrugated medium have a height from about 0.1 millimetres to about 5 millimetres. Even more preferably, the flutes of the corrugated medium have a height from about 1 millimetres to about 4 millimetres. Preferably, the flutes of the corrugated medium have a pitch of at least about 0.1 millimetres. More preferably, the flutes of the corrugated medium have a pitch of at least about 1 millimetres. In addition, or as an alternative, the flutes of the corrugated medium have a pitch of less than about 5 millimetres. More preferably, the flutes of the corrugated medium have a pitch of less than about 4 millimetres. In some preferred embodiments, the flutes of the corrugated medium have a pitch from about 0.1 millimetres to about 5 millimetres. Even more preferably, the flutes of the corrugated medium have a pitch from about 1 millimetres to about 4 millimetres.

Corrugated tobacco sheets according to the present invention may find application in the manufacture of tobacco products. In particular, a tobacco cut filler may be manufactured from portions of a corrugated tobacco sheet according to the invention. The portions may have a mean cut width from about 0.7 millimetres and about 1 .5 millimetres.

In preferred embodiments, the step of cutting the corrugated tobacco sheet to a predetermined mean cut width is carried out by cutting the corrugated tobacco sheet perpendicular to the longitudinal axes of the flutes. This advantageously maximizes the filling power of resulting cut filler.

A tobacco cut filler comprising portions of a corrugated web of reconstituted tobacco in accordance with the present invention can be used in the manufacture of a tobacco product. Preferably, a tobacco product comprises at least about 3 weight percent of corrugated cut filler relative to the total tobacco weight in the tobacco product. In addition, or as an alternative, a tobacco product preferably comprises less than about 15 weight percent of corrugated cut filler relative to the total tobacco weight in the tobacco product. In some preferred embodiment, a tobacco product comprises from about 3 weight percent to about 15 weight percent of corrugated cut filler relative to the total tobacco weight in the tobacco product.

In methods according to the present invention, a corrugated tobacco sheet is manufactured from a first web of reconstituted tobacco, which is shaped into a corrugated configuration with flutes to form a corrugated medium having a first and a second side.

Preferably, a second web of reconstituted tobacco is provided to form a liner and, as such, it is adhered to the first side of the corrugated medium. Thus, a one-sided corrugated sheet is obtained.

In some embodiments, a third web of reconstituted tobacco is provided to form a reinforcing liner and, as such, is adhered to the second side of the corrugated medium. Thus, a two-sided corrugated sheet is obtained.

Preferably, the method of manufacturing a corrugated tobacco sheet comprises the step of adjusting the moisture content of one or more of the webs of reconstituted tobacco. By way of example, the one or more webs of reconstituted tobacco may be provided with an initial moisture content of from about 10 percent by weight to about 15 percent by weight. In the step of adjusting the moisture of the one or more webs of reconstituted tobacco, the moisture content may preferably be raised to at least about 20 percent by weight, more preferably to at least about 40 percent by weight. In addition, or as an alternative, the moisture content is preferably raised to less than about 60 percent by weight, more preferably to less than about 50 percent by weight. In some embodiments of a method according to the invention, the moisture content of the first web of reconstituted tobacco is adjusted prior to the step of shaping it into a corrugated configuration. Thus, formation of the flutes in the first web of reconstituted tobacco is made easier.

A method of forming a tobacco cut filler constituent in accordance with the present invention further comprises cutting the corrugated tobacco web to a predetermined mean cut width.

The resulting cut filler may advantageously be used in the manufacture of a tobacco product. In a preferred embodiment, the resulting cut filler is advantageously used in the manufacture of a tobacco rod for a smoking article.

The invention will now be further described, by way of example only, with reference to the accompanying drawings in which:

Figure 1 shows a perspective schematic view of a one-sided corrugated sheet in accordance with the present invention; and

Figure 2 shows a perspective view of a two-sided corrugated sheet in accordance with the present invention.

Figure 1 illustrates a corrugated tobacco sheet 1 . The sheet 1 comprises a corrugated medium 2 and a liner 3. The medium 2 and the liner 3 are both formed from a web of reconstituted tobacco, which may be stocked in the form a roll 100. The medium 2 comprises a plurality of flutes 4 and has a first side and a second side. The flutes of the corrugated medium have a height H of about 2 millimetres and a pitch P of about 3.5 millimetres. The liner 3 is substantially flat and is adhered to the first side of the medium 2 by means of a binder such as guar gum. As illustrated in Figure 1 , the corrugated tobacco sheet 1 is flexible enough to be wound into a roll 100, which is advantageous for storage and transportation.

Figure 2 shows another embodiment 10 of a corrugated tobacco sheet according to the present invention. The corrugated tobacco sheet 10 differs from the corrugated tobacco sheet 1 of Figure 1 in that it comprises a second liner 5. The second liner 7 is substantially flat and is adhered to the second side of the medium 2 by means of a binder such as guar gum. The corrugated tobacco sheet 10 has an even further increased resilience compared with the corrugated tobacco sheet 1 .

Claims

1 . A corrugated tobacco sheet comprising:

a corrugated medium comprising a plurality of flutes and having a first and a second side; and

at least one liner;

wherein a first liner adheres to the first side of the corrugated medium and the corrugated medium and the liner are formed from a web of reconstituted tobacco.

2. A corrugated tobacco sheet according to claim 1 , comprising a second liner adhering to the second side of the corrugated medium, the second liner being formed from a web of reconstituted tobacco.

3. A corrugated tobacco sheet according to any one of the preceding claims, wherein each of the mediums and liners substantially consist of reconstituted tobacco.

4. A corrugated tobacco sheet according to any one of the preceding claims, wherein the flutes of the corrugated medium have a height from about 1 millimetres to about 4 millimetres.

5. A corrugated tobacco sheet according to any one of the preceding claims, wherein the flutes of the corrugated medium have a pitch from about 1 millimetres to about 4 millimetres.

6. A corrugated tobacco sheet comprising a corrugated medium comprising a plurality of flutes and having a first and a second side, the corrugated medium being formed from a web of reconstituted tobacco.

7. A corrugated tobacco cut filler comprising portions of a corrugated tobacco sheet according to any one of claims 1 to 6, the portions having a mean cut width from about 0.7 millimetres to about 1 .5 millimetres.

8. A tobacco product comprising a corrugated tobacco cut filler according to claim 7.

9. A tobacco product according to claim 8, wherein the amount of the corrugated cut filler is from about 3 weight percent to about 15 weight percent of the total tobacco weight.

10. A method of manufacturing a corrugated tobacco sheet comprising:

providing a first web of reconstituted tobacco; shaping the first web of reconstituted tobacco into a corrugated configuration with flutes to form a corrugated medium having a first and a second side.

1 1 . A method according to claim 10, further comprising the steps of:

providing a second web of reconstituted tobacco to form a liner;

adhering the liner to the first side of the corrugated medium.

12. A method according to claim 1 1 , further comprising the steps of:

providing a third web of reconstituted tobacco to form a reinforcing liner;

adhering the reinforcing liner to the second side of the corrugated medium.

13. A method of manufacturing a tobacco cut filler constituent, the method comprising the steps of any one of claims 10 to 12 and further comprising cutting the corrugated tobacco web to a predetermined mean cut width.

14. Use of a tobacco cut filler according to claim 7 for the manufacture of a tobacco product.

15. Use of a tobacco cut filler according to claim 7 for the manufacture of a tobacco rod for a smoking article.