HYDROPHOBIC TIPPING PAPER

Abstract

A smoking article includes a tobacco substrate and a mouthpiece axially aligned in an abutting end to end relationship with the tobacco substrate. Hydrophobic tipping paper is disposed about the mouthpiece. The tipping paper is hydrophobic due to hydrophobic groups covalently bonded to the tipping paper.

Claims

1. A method for making a smoking article comprising the steps of: applying a liquid composition comprising a fatty acid halide to a surface of a tipping paper, maintaining the surface at a temperature of about 120° C. to about 180° C., wherein the fatty acid halide reacts in situ with protogenic groups of material in the tipping paper resulting in the formation of fatty acid esters, and forming a hydrophobic tipping paper; and disposing the hydrophobic tipping paper about an axially aligned mouthpiece and tobacco substrate to form a smoking article, and define an outer surface of the mouthpiece of the smoking article.

2. The method according to claim 1 wherein the hydrophobic tipping paper comprises cellulosic material and a hydrophobic group is covalently bonded to the cellulosic material.

3. The method according to claim 2 wherein the hydrophobic group is covalently bonded to cellulosic material of the tipping paper by reacting in situ a fatty acid chloride with the cellulosic material.

4. The method according to claim 3 wherein the fatty acid chloride is palmitoyl chloride, stearoyl chloride, behenoyl chloride, or a mixture of palmitoyl chloride and stearoyl chloride.

5. The method according to claim 1 wherein the tipping paper comprising cellulosic material which comprises hydroxyl groups that react in situ with stearoyl chloride or palmitoyl chloride.

6. The method according to claim 1 wherein the applying step comprises printing the liquid composition comprising a fatty acid halide on a surface of a tipping paper.

7. The method according to claim 1 wherein the applying step comprises printing the liquid composition comprising a fatty acid halide on at least one surface of a tipping paper at a rate in a range from about 0.1 to about 3 grams per square meter to render the at least one surface of a tipping paper hydrophobic

8. The method according to claim 1 wherein the hydrophobic tipping paper has a water contact angle of at least about 100 degrees.

9. The method according to claim 1 wherein the tipping paper has a basis weight in a range from about 30 to about 90 grams per square meter and the fatty acid halide has a basis weight in a range from about 0.1 to about 3 grams per square meter.

10. The method according to claim 1 wherein the hydrophobic tipping paper exhibits a Cobb measurement value (60s) of less than 20 g/m.sup.2.

11. The method according to claim 1 wherein the disposing step fixes the mouthpiece to the tobacco substrate.

12. The method according to claim 1 wherein the forming a hydrophobic tipping paper reduces a permeability of the tipping paper by less than 10% as compared to a permeability of the tipping paper before the applying and maintaining steps.

13. The method according to claim 1 wherein the applying step comprises applying a liquid composition comprising a fatty acid halide to only an outer surface of a tipping paper and the hydrophobic tipping paper is rendered hydrophobic on both the outer surface and an opposing inner surface.

14. The method according to claim 1 wherein the applying step comprises applying a liquid composition comprising a fatty acid halide to only an outer surface of a tipping paper having a thickness in a range from 40 to 60 micrometers.

15. The method according to claim 1 wherein the applying step comprises applying a liquid composition comprising a fatty acid halide to only a mouth end portion of a tipping paper, wherein a portion of the tipping paper adjacent to the tobacco substrate is free of the liquid composition.

16. The method according to claim 1 wherein the applying step comprises applying a liquid composition comprising a fatty acid halide to a surface of a tipping paper in a pattern of at least 100 discrete islands.

17. The method according to claim 1 wherein the mouthpiece comprises a filter and the filter comprises cellulose acetate tow.

18. The method according to claim 1 wherein the mouthpiece comprises a filter and a liquid release capsule disposed within the filter.

19. The method according to claim 1 wherein the tobacco substrate comprises from 10% to 30% humectant, on a dry weight basis.

20. The method according to claim 1 wherein the tobacco substrate comprises from 20% to 30% humectant, on a dry weight basis.

Description

[0048] According to the invention, a hydrophobic tipping paper can be produced by a process comprising applying a liquid composition comprising a aliphatic acid halide to at least one surface of a tipping paper, optionally applying a gas stream to the surface to aid diffusion of the applied fatty acid halide, and maintaining the surface at a temperature about 120° C. to about 180° C., wherein the fatty acid halide reacts in situ with the hydroxyl groups of the cellulosic material in the tipping paper resulting in the formation of aliphatic acid esters. Preferably, the tipping paper is made of paper, and the fatty acid halide is stearoyl chloride, palmitoyl chloride, or a mixture of fatty acid chlorides with 16 to 20 carbon atoms in the acyl group. The hydrophobic tipping paper produced by a process described hereinabove is thus distinguishable from material made by coating the surface with a layer of pre-made fatty acid ester of cellulose.

[0049] The hydrophobic tipping paper is produced by a process of applying the liquid reagent composition to the at least one surface of a tipping paper at a rate of in a range from about 0.1 to about 3 grams per square meter, or from about 0.1 to about 2 grams per square meter, or from about 0.1 to about 1 gram per square meter. The liquid reagent applied at these rates renders the surface of a tipping paper hydrophobic.

[0050] Smoking articles, such as cigarettes and aerosol generating articles, include a tobacco substrate or an aerosol generating substrate that comprises a charge of tobacco circumscribed by a wrapper. The tobacco substrate may comprise any suitable type or types of tobacco material or tobacco substitute, in any suitable form. Preferably, the tobacco rod includes flue-cured tobacco, Burley tobacco, Maryland tobacco, Oriental tobacco, specialty tobacco, or any combination thereof. Preferably, the tobacco is provided in the form of tobacco cut filler, tobacco lamina, processed tobacco materials, such as volume expanded or puffed tobacco, processed tobacco stems, such as cut-rolled or cut-puffed stems, homogenized tobacco, reconstituted tobacco, cast leaf tobacco, or blends thereof, and the like. The term “tobacco cut filler” is used herein to indicate tobacco material that is predominately formed from the lamina portion of the tobacco leaf. The terms “tobacco cut filler” is used herein to indicate both a single species of Nicotiana and two or more species of Nicotiana forming a tobacco cut filler blend.

[0051] As used herein, the term “homogenized tobacco” denotes a rod or a sheet of material formed by agglomerating particulate tobacco by-products, such as tobacco fines, tobacco dusts, tobacco stems, or a mixture of the foregoing, and may include reconstituted tobacco, cast leaf tobacco, or both. The term “reconstituted tobacco” refers to a paper-like material that can be made from tobacco by-products by extracting the soluble chemicals in the tobacco by-products, processing the leftover tobacco fibers from the extraction into a paper-like sheet, and then reapplying the extracted materials in concentrated form onto the sheet. The term “cast leaf tobacco” refers to a paper-like material made by casting a slurry comprising particulate tobacco by-products and a binder (for example, guar) onto a supportive surface, such as a belt conveyor, drying the slurry and removing the dried sheet from the supportive surface. Exemplary methods for producing various types of homogenized tobacco are described in U.S. Pat. Nos. 5,724,998; 5,584,306; 4,341,228; 5,584,306 and 6,216,706.

[0052] The tobacco substrate or aerosol-generating substrate can include a high level of humectant material. Humectant material can be referred to as an “aerosol former”. An aerosol former is used to describe any suitable known compound or mixture of compounds that, in use, facilitates formation of an aerosol and that is substantially resistant to thermal degradation at the operating temperature of the tobacco substrate or aerosol-generating substrate.

[0053] Suitable humectants or aerosol-formers are known in the art and include, but are not limited to: polyhydric alcohols, such as propylene glycol, triethylene glycol, 1,3-butanediol and glycerine; esters of polyhydric alcohols, such as glycerol mono-, di- or triacetate; and aliphatic esters of mono-, di- or polycarboxylic acids, such as dimethyl dodecanedioate and dimethyl tetradecanedioate. Preferred humectants or aerosol formers are polyhydric alcohols or mixtures thereof, such as propylene glycol, triethylene glycol, 1,3-butanediol and, most preferred, glycerine. The tobacco substrate or aerosol-forming substrate may comprise a single humectant or aerosol former. Alternatively, the tobacco substrate or aerosol-generating substrate may comprise a combination of two or more humectants or aerosol formers.

[0054] In many embodiments, the tobacco substrate or aerosol-generating substrate has a humectant or aerosol former content of greater than about 10% or preferably greater than about 15% or more preferably greater than about 20%, on a dry weight basis. The tobacco substrate or aerosol-forming substrate has a humectant or aerosol former content of between about 10% and about 30%, or preferably from about 15% and about 30%, or more preferably from about 20% and about 30%, on a dry weight basis.

[0055] The mouthpiece of smoking articles in accordance with the present invention may comprise a filter including one or more filter segments of filtration material. For example, the mouthpiece may comprise a single segment of filtration material, or the mouthpiece may comprise a multi-segment filter including two or more segments of filtration material. Where two or more filter segments are provided, the filter segments may be of the same construction and materials as each other. Preferably, however, the filter segments have a different construction, and/or contain different filtration material to each other. In any of the embodiments in which the mouthpiece comprises one or more segments of filtration material, at least one of the filter segments may include a flavourant material.

[0056] The flavourant may be provided directly onto a component of a filter. Alternatively, the flavourant may be provided as part of a flavourant delivery component that is configured to release the flavourant in response to a trigger mechanism. In some embodiments, the flavourant is a particulate flavourant material. Suitable particulate flavourant materials include particles of a sorbent or cellulosic material impregnated with a liquid flavourant.

[0057] The term “liquid release component” is used herein to refer to a discrete piece or portion of a liquid delivery material which is in a form that is suitable to be incorporated into a smoking article or aerosol-generating article. The liquid release component releases a liquid comprising a functional material. The liquid release component is preferably in the form of a bead, a capsule or a microcapsule. In preferred embodiments, the liquid release component is a flavourant delivery component for providing flavour in a smoking article. As used herein, the term “liquid” refers to compositions that are in a liquid state at room temperature, for example, 22° C.

[0058] In some embodiments, the flavourant is provided in a capsule which is adapted to release at least a portion of a liquid when the capsule is subjected to external force, such as squeezing, by the consumer. Thus, rupturing the capsule releases an amount of liquid flavourant into the filter segment or filtration material. The capsule can comprise an outer shell and an inner core containing the flavourant. Preferably, the outer shell is sealed before the application of an external force, but is frangible or breakable to allow the flavourant to be released when the external force is applied. The capsule may be formed in a variety of physical formations including, but not limited to, a single-part capsule, a multi-part capsule, a single-walled capsule, a multi-walled capsule, a large capsule, and a small capsule. Alternatively, the liquid flavourant is contained in a liquid releasing component which comprises a matrix structure defining a plurality of domains enclosing the liquid flavourant and which provides a sustained-release delivery profile, such that the amount of the flavour composition released upon compression of the flavour release component can be controlled through the adjustment of the compressive force applied by the consumer. Those of skill in the art will understand that the term “sustained release” covers those embodiments in which the amount of flavourant released at a given force depends additionally on the duration of the applied force.

[0059] In many embodiments the overall length of the smoking article is between about 70 mm and about 130 mm or is between about 30 mm and about 100 mm. In some embodiments the overall length of the smoking article is about 85 mm or about 45 mm. The external diameter of smoking article can be between about 5.0 mm and about 12 mm, or between about 5.0 mm and about 8 mm, or 7.2 mm±10%. The overall length of the filter of the smoking article can be between about 18 mm and about 36 mm. In some embodiments the overall length of the filter is about 27 mm.

[0060] Where the mouthpiece includes one or more segments of filtration material, the filtration material is preferably a plug of fibrous filtration material, such as cellulose acetate tow or paper. A filter plasticiser may be applied to the fibrous filtration material in a conventional manner, by spraying it onto the separated fibres, preferably before applying any particulate material to the filtration material. The mouthpiece may include a variety of different types of filter segments or combinations of filter segments, including those described above as well as other types of filter segments that would be known to the skilled person, such as segments including restrictors and segments that are used for adjusting the resistance to draw (RTD).

[0061] The resistance to draw (RTD) of the smoking articles and the filters of the present disclosure can vary. In many embodiments the RTD of the smoking article is between about 50 to 130 mm H.sub.2O. The RTD of a smoking article refers to the static pressure difference between the two ends of the specimen when it is traversed by an air flow under steady conditions in which the volumetric flow is 17.5 millilitres per second at the output end. The RTD of a specimen can be measured using the method set out in ISO Standard 6565:2002 with any ventilation (if present) blocked.

[0062] In one or more embodiments, smoking articles according to the present disclosure may be packaged in containers, for example in soft packs or hinge-lid packs, with an inner liner coated with one or more flavourants.

[0063] All scientific and technical terms used herein have meanings commonly used in the art unless otherwise specified. The definitions provided herein are to facilitate understanding of certain terms used frequently herein.

[0064] The term “tobacco substrate” or “aerosol-generating substrate” includes a rod of tobacco formed of shredded tobacco or tobacco cut filler, or it may include reconstituted tobacco or cast leaf tobacco, or a mixture of both. The tobacco substrate can be connected to the mouthpiece or filter in an end-to-end relationship, as further discussed below.

[0065] The term “tobacco cut filler” is used herein to indicate tobacco material that is predominately formed from the lamina portion of the tobacco leaf. The terms “tobacco cut filler” is used herein to indicate both a single species of Nicotiana and two or more species of Nicotiana forming a tobacco cut filler blend.

[0066] As used in this specification and the appended claims, the singular forms “a”, “an”, and “the” encompass embodiments having plural referents, unless the content clearly dictates otherwise.

[0067] As used in this specification and the appended claims, the term “or” is generally employed in its sense including “and/or” unless the content clearly dictates otherwise.

[0068] As used herein, “have”, “having”, “include”, “including”, “comprise”, “comprising” or the like are used in their open ended sense, and generally mean “including, but not limited to”. It will be understood that “consisting essentially of”, “consisting of”, and the like are subsumed in “comprising,” and the like.

[0069] The words “preferred” and “preferably” refer to embodiments of the invention that may afford certain benefits under certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the disclosure, including the claims.

[0070] FIG. 1 is a schematic perspective view of an embodiment of a partially unrolled smoking article.

[0071] The smoking articles depicted in FIG. 1 illustrate one or more embodiments of smoking articles or components of smoking articles described above. The schematic drawings are not necessarily to scale and are presented for purposes of illustration and not limitation. The drawings depict one or more aspects described in this disclosure. However, it will be understood that other aspects not depicted in the drawings fall within the scope and spirit of this disclosure.

[0072] Referring now to FIG. 1, a smoking article 10 is depicted. The smoking article 10 includes a tobacco substrate 20, such as a tobacco rod, and a mouth end segment 30 and a lit end tip 70. The mouthpiece 30 can abut the tobacco substrate 20 in the finished smoking article 10. The depicted smoking article 10, includes a plug wrap 60 that circumscribes at least a portion of the filter or mouthpiece segment 30 and a wrapper 40 that circumscribes at least a portion of the tobacco substrate 20. Hydrophobic tipping paper 50 circumscribes the plug wrap 60 and a portion of the wrapper 40.

[0073] The exemplary embodiments described above are not limiting. Other embodiments consistent with the exemplary embodiments described above will be apparent to those skilled in the art.