Plug Wrap or Tipping Paper for Smoking Articles

The present invention relates to plug wrap or tipping paper (5) for smoking articles (1). More particularly, the present invention relates to plug wrap or tipping paper for smoking articles, wherein the plug wrap and tipping paper comprises a sheet having two or more plies (10,11) and one of the plies comprises adsorbent material. The present invention also relates to a method of preparing the plug wrap and tipping paper, and smoking articles comprising the plug wrap and/or tipping paper.

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Description

FIELD OF THE INVENTION

The present invention relates to a plug wrap for a smoking article. The present invention relates also to a tipping paper for a smoking article. The present invention relates also to a method of making a plug wrap or tipping paper for a smoking article.

BACKGROUND

Smoking articles are known wherein an adsorbent-containing web material is positioned between the smoking material rod and the wrapper therefor. For example, WO 2005/082180 discloses smoking articles comprising a rod of smokable material, a wrapper about the rod of smokable material and a web material comprising an adsorbent material and a flavourant, the web material being positioned between the rod of smokable material and the wrapper and advantageously being adhered to the wrapper using an adhesive. The adsorbent material may absorb components of the smoke produced from the smoking material rod, and for example may be carbon. In WO 2005/082180 a filler material such as calcium carbonate and a burn additive such as citrate are advantageously used.

Further, wrappers for smoking articles in which the wrapper is formed as a single sheet are known. For example EP-A-0 407 022 discloses a wrapper for smoking articles in which the wrapper comprises a single paper sheet formed from two or more discrete webs, the webs being combined while at least one of the webs is still in the wet stage of formation before drying. Additionally, EP-A-0 475 580 discloses a wrapper for smoking articles, the wrapper comprising a single paper sheet having two or more plies, each ply being formed from a paper stock and wherein the paper stocks are applied to each other while at least one of the stocks is unformed. In both EP-A-0 407 022 and EP-A-0 475 580 one of the plies may contain carbon.

However, the above-mentioned documents do not disclose the use of such combined wrappers as a plug wrap or as tipping paper.

Applicant has now found that, by enwrapping a filter element in a plug wrap or tipping paper comprising at least two plies and wherein said plug wrap or tipping paper comprises a ply containing adsorbent material, characteristics of a smoking article incorporating the filter may be altered advantageously.

SUMMARY OF THE INVENTION

According to the present invention there is provided a plug wrap or tipping paper for a smoking article, which comprises a sheet comprising first and second plies, wherein:

    • the first ply comprises fibrous material; and
    • the second ply comprises fibrous material, and adsorbent material.

It is advantageous to include adsorbent material in the plug wrap or tipping paper for a number of reasons. In particular, the inclusion of adsorbent in the material constituting the plug wrap or tipping paper allows the use of smaller particles, having a greater surface area to volume ratio, than is found with granules included in filters for instance. Additionally, the inclusion of adsorbent in the material constituting the plug wrap or tipping paper avoids the need for adhesive to adhere adsorbent particles to a plug wrap, as is found for instance in EP 0 579 410. Other benefits and advantages will be apparent from the following description.

Although the sheet may comprise more than two plies, it is advantageous that the sheet is a double ply sheet, i.e. has only two plies.

The fibrous material present in the first and/or second ply may be a fibrous cellulosic material, for instance a paper material.

The fibrous material may, for example, be present in the second ply in an amount of up to 40 gsm.

The fibrous material may, for example, be present in first ply in an amount of up to 20 gsm.

The total amount of fibrous material in the sheet may be at least 17 gsm. The total amount of fibrous material in the sheet may be up to 60 gsm.

The adsorbent material present in the second ply may, for example, be carbon, for instance activated carbon. Advantageously, the activated carbon has an activity level (CTC) of from 60 to 130, and further advantageously from 80-120, and may suitably be approximately 100.

The adsorbent material may, for example, be in powder or particulate form. It may be in granular form.

The adsorbent material may, for example, be present in the second ply in an amount of up to 40 gsm.

The total amount of adsorbent material in the sheet may, for example, be up to 40 gsm.

The first and/or second ply may, for example, comprise filler material. Examples of suitable filler materials include calcium carbonate titanium dioxide, magnesium oxide, calcium sulphate, clays and kaolins. The filler material may comprise calcium carbonate.

The filler material may, for example, be present in the second ply in an amount of up to 25 gsm. The filler material may, for example, be present in the first ply in an amount of up to 15 gsm. The total amount of filler material in said sheet may, for example, be at least 8 gsm. The total amount of filler material in the sheet may, for example, be up to 40 gsm.

The second layer of the plug wrap or tipping paper may, for example, comprise flavourant. This is particularly suited to tipping paper.

The flavourant is advantageously flavourant selected from the following compound types: menthol (natural and/or synthetic), alcohols, esters, ketones, lactones, essential oils, aldehydes and heterocyclic compounds. A suitable flavourant is menthol.

The plug wrap or tipping paper may, for example, have a thickness of at least 45 μm. The plug wrap or tipping paper may, for example, have a thickness of up to 250 μm.

The second ply extends over at least a part of one surface of the first ply.

It is to be understood that, in the situation where more than two plies are present in the sheet, the second ply may be separated from the first ply by additional plies.

The second ply may extend over the whole of one surface of the first ply.

In some embodiments of the present invention, the second ply comprises diluent.

If present, the flavourant may be added to the adsorbent material prior to forming the second layer. For example, the flavourant may be added to the adsorbent material by spraying.

Alternatively, the flavourant may be added to the second layer after formation of that layer. A further alternative is wherein the flavourant is added to the second layer after formation of the plug wrap or tipping paper.

For example, the flavourant may be added to the second layer using a flavour applicator means, advantageously as a stream or streams of flavourant. Suitably, the plurality of streams of flavourant is applied to the second layer in a line or in an array. When applied in an array, the array may comprise two lines of streams of flavourant, one of the lines being offset from the streams of flavourant in an adjacent line. Suitably, the flavourant is applied to the surface of the second layer as 1 to 30 streams of flavourant, and advantageously as 4 to 18 streams of flavourant.

If the flavourant is solid at room temperature, it can be heated to maintain the flavourant in the molten liquid state during application to the adsorbent or the second layer, and is advantageously heated to a temperature of 40 to 45° C.

The plug wrap or tipping paper may be formed by any suitable method provided that the resultant plug wrap or tipping paper comprises a single sheet. As used herein the term “single sheet” refers to a sheet in which the plies thereof are integral in the sense that the plies are not merely placed adjacent to one another or adhered to one another using such as adhesive (i.e. as in the case of WO 2005/082180).

In embodiments of the present invention, the plug wrap or tipping paper in the form of a single sheet is formed by combining the two or more plies to form the single sheet while at least one of the plies is in the wet stage of formation prior to drying. For example, when the plug wrap or tipping paper is a double ply sheet, the plies may be combined while one or of the plies is in the wet stage of formation prior to drying, or while both of the plies are in the wet stage of formation prior to drying.

In embodiments wherein the sheet is a single sheet comprising two or more plies, the first ply is a first ply and the second ply is a second ply, the method may comprise combining the plies while at least one of the plies is still in the wet stage of formation prior to drying. After combining the plies the formed sheet is typically dried.

An apparatus suitable for use in preparing the plug wrap or tipping paper may, for example, be a multi-wire paper making machine such as a double wire paper making machine.

The present invention further provides a smoking article comprising a wrapped rod of smoking material, and a filter element, wherein the filter element comprises a filter rod and a plug wrap enwrapping the filter rod, the plug wrap being a plug wrap according to the present invention or a plug wrap prepared according to the method of the present invention. In such smoking article the second ply of the plug wrap is advantageously located on the filter rod side of the plug wrap. This allows the adsorbent material to be relatively proximate to the flow of smoke through the smoking article, thereby allowing greater interaction with constituents of the smoke than would be the case if the second ply were an outer ply. This also allows the outward appearance of the plug wrap not to be affected, or to be affected less, by the content of the second ply. This is particularly useful in the case where the adsorbent material in the second ply is carbon.

The present invention still further provides a smoking article comprising a wrapped rod of smoking material, a filter element, and wherein the filter element is attached to the rod of smoking material by means of a tipping paper, the tipping paper being a tipping paper according to the present invention or a tipping paper prepared according to the method of the present invention. In such smoking article the second ply of the tipping paper is advantageously located on the filter rod side of the tipping paper. This allows the adsorbent material to be relatively proximate to the flow of smoke through the smoking article, thereby allowing greater interaction with constituents of the smoke than would be the case if the second ply were an outer ply. This also allows the outward appearance of the tipping paper not to be affected, or to be affected less, by the content of the second ply. This is particularly useful in the case where the adsorbent material in the second ply is carbon. Further, in such smoking article the filter element may comprise a filter rod enwrapped in a plug wrap, with the plug wrap being located between the filter rod and the tipping paper.

The present invention still further provides a smoking article comprising a wrapped rod of smoking material, a filter element, wherein (a) the filter element comprises a filter rod and a plug wrap enwrapping the filter rod, the plug wrap being a plug wrap according to the present invention or a plug wrap prepared according to the method of the present invention, and (b) the filter element is attached to the rod of smoking material by means of a tipping paper, the tipping paper being a tipping paper according to the present invention or a tipping paper prepared according to the method of the present invention. In such smoking article the second ply of the plug wrap is advantageously located on the filter rod side of the plug wrap. This allows the adsorbent material to be relatively proximate to the flow of smoke through the smoking article, thereby allowing greater interaction with constituents of the smoke than would be the case if the second ply were an outer ply. This also allows the outward appearance of the plug wrap not to be affected, or to be affected less, by the content of the second ply. This is particularly useful in the case where the adsorbent material in the second ply is carbon. Further, in such smoking article, the second ply of the tipping paper is advantageously located on the filter rod side of the tipping paper.

The second ply of the plug wrap and/or the tipping paper is advantageously located on the filter rod side of said plug wrap and/or tipping paper. This can be more aesthetically pleasing to the smoker. That is, the second ply, which contains the adsorbent material, is located between the first ply and the filter rod such that the second ply is not visible to the smoker. Furthermore, in this arrangement the adsorbent material will have greater interaction with constituents of the smoke during smoking (compared to the second ply being on the outer surface of the plug wrap/tipping wrapper).

In the smoking article according to the present invention the filter element may comprise a filter rod comprising adsorbent material. Examples of suitable adsorbent materials include carbon. Advantageously, the adsorbent material is carbon and more advantageously is activated carbon. Any form of activated carbon may be used. Advantageously, the activated carbon has an activity level (CTC) of from 60 to 130, and preferably from 80-120, and suitably for example approximately 100.

The adsorbent material, when present in the filter element, may, for example, be in granular, powder or particulate form.

The filter element may be a multiple filter comprising multiple sections such as, for example, a dual or triple filter. Suitable filters are well known to those skilled in the art. A preferred filter element contains adsorbent material for the reduction of vapour phase constituents of smoke. Such filters known in the art include Dalmation filters in which particulate adsorbent material is interspersed in fibrous filter material, for example fibrous cellulosic material, and cavity filters in which a cavity portion of the multi-segment filter contains adsorbent material. When the second layer contains flavourant, such flavourant is released from the second layer during smoking of the smoking article without adversely affecting the ability of the adsorbent in the filter to reduce vapour phase constituents of the smoke.

In the embodiment of the present invention wherein the smoking article comprises a filter element comprising a filter rod, and wherein the filter rod comprises adsorbent material, the filter rod may comprise a cellulose acetate mouth end section and a Dalmation rod section, containing the adsorbent material, located at the smoking material rod end of the filter element.

Alternatively, in the embodiment of the present invention wherein the smoking article comprises a filter element comprising a filter rod, and wherein the filter rod comprises adsorbent material, the filter rod may be a cavity filter comprising two end sections and a central cavity containing said adsorbent material.

When the filter rod of a smoking article comprises adsorbent material, the presence of adsorbent material in the plug wrap and/or tipping paper according to the present invention increases the reduction in vapour phase components, compared to the use of the filter alone.

When the filter rod of a smoking article comprises adsorbent material, the presence of adsorbent in the plug wrap and/or tipping paper according to the present invention may improve the efficiency of the filter in reducing vapour phase constituents in smoke generated during smoking of the smoking article.

The filter element may alternatively comprise a filter plug of homogeneous filtration material, a plug wrap overwrapping the filter plug, circumferentially spaced grooves extending longitudinally of the filter plug, and a ventilating tipping paper interconnecting the filter element to a tobacco rod, a number of grooves being open on the side of the tobacco rod and extending continuously only over a part of the length of the filter element, and hence not up to the mouth end of the filter element, which grooves are axially aligned with respect to the filter axis, in to which axially extending grooves ventilating air enters via overlying ventilating tipping paper, and any mouth extending groove not being ventilated.

The smoking material may be a tobacco-containing smoking material or a non-tobacco-containing smoking material. Advantageously the smoking material is a tobacco-containing material, and more advantageously the smoking material is a tobacco material. Suitably, the tobacco material comprises of stem, lamina and tobacco dust. An example, of a tobacco material is one containing of the following tobacco types: Virginia or flue-cured tobacco, Burley tobacco, Oriental tobacco, reconstituted tobacco and stem. Advantageously, the smoking material comprises a blend of tobacco material.

In a smoking article according to the present invention, the tipping paper may enwrap the whole of the filter element and extend part of the way along the smoking material rod. Alternatively, the tipping paper may be a narrow strip of material which extends over only a part, for example a small part, of the length of the filter element and smoking material rod.

In embodiments of the present invention, the smoking article is a cigarette.

According to a second aspect of the invention there is provided a method of making a plug wrap or tipping paper for a smoking article, the method comprising combining a first ply comprising fibrous material and a second ply comprising fibrous material and adsorbent material to make a two-ply sheet.

By practice of the present invention there may be provided of the following:

a) a plug wrap and/or tipping paper that may be used in forming a smoking article and which enables a reduction in the vapour phase constituents of the smoke delivered to the smoker to be achieved;
b) a plug wrap and/or tipping paper which can be produced having a thickness similar to that of conventional plug wrap and tipping paper such that the plug wrap and tipping paper can be used in conventional smoking article (e.g. cigarette) manufacturing machinery for producing smoking articles and thereby avoid the cost of additional machinery;
c) a plug wrap and/or tipping paper comprising two or more plies with one of the plies comprising adsorbent material(s), which plug wrap and/or tipping paper can be formed remote from the smoking article making machine, this being advantageous as it reduces the complexity of the manufacturing machinery required by the smoking article manufacturer because the smoking article manufacturer does not require machinery to manufacture the sheet itself; and
d) a plug wrap and/or tipping paper that enables flavourant to be incorporated and stabilised therein, such that the flavourant is not released until smoking of a smoking article.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 shows a cross-section longitudinally through a smoking article with a filter rod including a plug wrap and a tipping paper according to the invention;

FIG. 2 shows two plies used to make the plug wrap and tipping paper of the smoking article of FIG. 1;

FIG. 3 shows a cross-section through the filter rod of FIG. 1 along line x-x including a 2-ply plug wrap and a conventional tipping paper;

FIG. 4 shows a cross-section through the filter rod of FIG. 1 along line x-x including a 2-ply tipping paper and a conventional plug wrap;

FIG. 5 shows a cross-section through the filter rod of FIG. 1 along line x-x including a 2-ply plug wrap and a 2-ply tipping paper; and

FIG. 6 shows a flow chart of a process of making the 2-ply single sheet of FIG. 2.

DETAILED DESCRIPTION

FIG. 1 shows a smoking article 1 in longitudinal cross-section. The smoking article 1 comprises a rod 2 of smokable material enwrapped by a wrapper 4 and a filter rod 3. The filter rod 3 is positioned at a mouth end of the smoking article 1. The filter rod 3 is enwrapped by a plug wrap 5. The filter rod 3 is attached to the rod of smokable material 2 by a tipping paper 6. Each of the wrapper 4, the plug wrap 5 and the tipping paper 6 is made of a respective single sheet.

The plug wrap 5 extends for the entire length of the filter rod 3 in the longitudinal axis of the smoking article 1. The plug wrap 5 thus enwraps the entire radial surface of the filter rod 3.

The filter rod 3 may be a multiple filter comprising multiple sections such as, for example, a dual or triple filter. Suitable filters are well known to those skilled in the art. The filter 3 may include adsorbent material, for instance activated carbon, for the reduction of vapour phase constituents of smoke. Suitable filters include Dalmation filters in which particulate adsorbent material is interspersed in fibrous filter material, for example fibrous cellulosic material, and cavity filters in which a cavity portion of the multi-segment filter contains one or more adsorbent material, for instance activated carbon. When the second ply is positioned near to the mouth end of the smoking article, it has been found that the flavourant is released from the second ply during smoking of the smoking article without being adsorbed by the adsorbent material of the filter and without adversely affecting the ability of the adsorbent in the filter to reduce vapour phase constituents of the smoke. It is possible that the smoke drawn through the filter during smoking is of such a temperature as to at least partially volatilise the flavourant.

The filter rod 3 may alternatively comprise a filter plug of homogeneous filtration material, a plug wrap overwrapping the filter plug, circumferentially spaced grooves extending longitudinally of the filter plug, and a ventilating tipping paper interconnecting the filter element to a tobacco rod, a number of grooves being open on the side of the tobacco rod and extending continuously only over a part of the length of the filter element, and hence not up to the mouth end of the filter element, which grooves are axially aligned with respect to the filter axis, in to which axially extending grooves ventilating air enters via overlying ventilating tipping paper, and any mouth extending groove not being ventilated.

The wrapper 4 and the plug wrap 5 meet at the boundary of the filter rod 3 and the smokable rod 2. The wrapper 4 and the plug wrap 5 do not overlap one another. The wrapper 4 and the plug wrap 5 are at least partially enwrapped by the tipping paper 6. The tipping paper 6 may extend over the whole length of the filter rod 3 and a part of the length of the smokable rod 2. Alternatively, the tipping paper 6 may extend over only a part of the filter rod 3 and a part of the length of the smokable rod 2.

The smokable rod 2 comprises a smoking material. The smoking material is a tobacco-containing smoking material or a non-tobacco-containing smoking material. The smoking material may be a tobacco-containing material, or a tobacco material. Suitably, the tobacco material comprises one or more of stem, lamina and tobacco dust. An example, of a tobacco material is one containing one or more of the following tobacco types: Virginia or flue-cured tobacco, Burley tobacco, Oriental tobacco, reconstituted tobacco and stem. The smoking material may comprise a blend of tobacco material.

FIG. 2 shows a sheet 8 comprising two plies 10, 11. The sheet 8 constitutes the plug wrap 5 and/or the tipping paper 6. The thickness of the plug wrap 5 and the tipping paper 6 is similar to that of conventional cigarette papers.

The first ply 10 is comprised of fibrous material. The second ply 11 is comprised of adsorbent material, fibrous material and optionally flavourant. In this embodiment, the adsorbent material is carbon. The fibrous material is a fibrous cellulosic material, such as paper. The flavourant, if present, may for instance be a menthol flavourant. The two plies 10, 11 are integral in the sense that they are not merely placed adjacent to one another or adhered to one another using such as an adhesive, but are formed as a single sheet. The sheets may be said to be adhered together by the fibre bonding inherent in the papermaking process. The plug wrap 5 and the tipping paper 6 are formed using a double-wire process, as described below.

FIG. 3 shows a transverse cross-section through the filter rod 3 of FIG. 1 along line x-x of FIG. 1 with 2-ply plug wrap 5 and with conventional tipping paper 6 enwrapping the filter rod 3. The first ply 20 of the plug wrap 5 is the external ply. The outer surface of the first ply 20 of the plug wrap 5 is adjacent to the inner surface of the tipping paper 6. The second ply 21 of the plug wrap 5 is the interior ply. The inner surface of the second ply 21 of the plug wrap 5 is adjacent to the filter rod 3. The outer surface of the tipping paper 6 corresponds to the exterior surface of the tipping paper 6 and thus the exterior surface of the smoking article 1.

FIG. 4 shows a transverse cross-section through the filter rod 3 of FIG. 1 along line x-x of FIG. 1 of an alternative embodiment. In this embodiment, there is provided conventional plug wrap 5 and 2-ply tipping paper 6 enwrapping the filter rod 3. The first ply 30 of the tipping paper 6 is the external ply. The outer surface of the first ply 30 of the tipping paper 6 corresponds to the exterior surface of the tipping paper 6 and thus the exterior surface of the smoking article 1. The second ply 31 of the tipping paper 6 is the internal ply. The inner surface of the second ply 31 of the tipping paper 6 is adjacent to the outer surface of the plug wrap 5. The inner surface of the plug wrap 5 is adjacent to the filter rod 3.

FIG. 5 shows a transverse cross-section through the filter rod 3 of FIG. 1 along line x-x of FIG. 1 with a still further embodiment. In this embodiment, there is provided 2-ply plug wrap 5 and 2-ply tipping paper 6 enwrapping the filter rod 3. The arrangement of the 2-ply plug wrap 5 is same as that of the embodiment shown in FIG. 3 and the arrangement of the 2-ply tipping paper 6 is same as that of the embodiment shown in FIG. 4. Thus, the outer surface of the first ply 20 of the plug wrap 5 is adjacent to the inner surface of the second ply 31 of the tipping paper 6.

In alternative embodiments, the plug wrap 5 is omitted. In these embodiments, the tipping paper 6 is formed of the sheet 8 shown in FIG. 2. Here, the tipping paper 6 extends over the whole length of the filter rod 3 and a part of the length of the smokable rod 2 and thus also serves the function of the plug wrap 5.

The following relates to all of the above-described embodiments.

Upon smoking, the smoking article 1 is ignited at the end furthest from the filter rod 3. Smoke is drawn along the smokable rod 2 to the smoker. The presence of the adsorbent material in the plug wrap and/or tipping paper improves the smoking article. This is achieved because the adsorbent material reduces vapour phase constituents generated during smoking of the smoking article 1.

FIG. 6 is a flow chart illustrating a method in making the sheet 8 which, as explained above can be used as 2-ply plug wrap 5 and/or 2-ply tipping paper 6.

At step S1, the first ply 10 and the second ply 11 are made separately. The first and second plies 10, 11 have different compositions. The plies 10, 11 may be of different thicknesses.

The first ply 10 comprises fibrous material and filler.

The fibrous material is a fibrous cellulosic material. Particularly, the fibrous cellulosic material is a paper material.

The filler may be calcium carbonate (chalk), titanium dioxide, magnesium oxide, calcium sulphate, clays or a kaolin. Advantageously the filler is calcium carbonate. The one or more filler material may, for example, be present in the second ply in an amount of up to 25 gsm. The one or more filler material may, for example, be present in the first ply in an amount of up to 15 gsm. The total amount of filler material in said sheet may, for example, be at least 8 gsm. The total amount of filler material in the sheet 8 may, for example, be up to 40 gsm.

The second ply 11 comprises adsorbent material, fibrous material, and optionally flavourant.

The fibrous material is a fibrous cellulosic material. Particularly, the fibrous cellulosic material is a paper material. The fibrous material is present in the second ply 11 in an amount of up to 40 gsm. The fibrous material is present in first second ply 11 in an amount of up to 20 gsm.

The adsorbent material may be carbon, or it may be another suitable adsorbent. The adsorbent material may be activated carbon. Any form of activated carbon may be used. The activated carbon may have an activity level (CTC) of from 60 to 130. Advantageously, the activated carbon has an activity level of about 100, or between 80 and 120, or approximately 100. The adsorbent material advantageously is in powder or particulate form. It may alternatively be in granular form. The adsorbent material is present in the second ply in an amount of up to 40 gsm.

The flavourant may be any of the following: menthol (natural and/or synthetic), alcohols, esters, ketones, lactones, essential oils, aldehydes and heterocyclic compounds. A different, suitable flavourant may be may used instead. The flavourant is added to the adsorbent material prior to forming the second ply. The flavourant may be added to the second ply 11, after the inclusion of the adsorbent material, by spraying. For example, the flavourant may be added to the second ply using a flavour applicator means, for instance as a stream or streams of flavourant. Suitably, the plurality of streams of flavourant is applied to the second ply in a line or in an array. When applied in an array, the array may comprise two lines of streams of flavourant, one of the lines being offset from the streams of flavourant in an adjacent line. Suitably, the flavourant is applied to the surface of the second ply as 1 to 30 streams of flavourant, and preferably as 4 to 18 streams of flavourant. If the flavourant is solid at room temperature, it is heated to maintain the flavourant in the molten liquid state during application to the second ply 11, and may be heated to a temperature of 40 to 45° C.

Alternatively, the flavourant can be added to the second ply 11 after formation of the two-ply paper.

In some embodiments, the second ply also comprises filler. The filler may be calcium carbonate (chalk), titanium dioxide, magnesium oxide, calcium sulphate, clays or a kaolin. Advantageously the filler is calcium carbonate. The filler material is present in the second ply in an amount of up to 25 gsm.

As well as considering the first and second plies 10, 11 separately, it can be useful to consider the materials and physical characteristics of the resulting paper when determining what compositions to give to the plies 10, 11.

The two-ply sheet has a thickness of at least 45 μm. The two-ply sheet has a thickness of up to 250 μm.

The total amount of filler material in the sheet is at least 8 gsm. The total amount of filler material in the sheet 8 is up to 40 gsm.

The total amount of fibrous material in the sheet is at least 17 gsm. The total amount of fibrous material in the sheet 8 is up to 60 gsm.

At step S2, the first and second plies 10, 11 are pressed together so as to form a single sheet of paper using a double-wire paper making machine. Double-wire paper making machines are well known in the art so this step will not be described in detail. The result is a sheet of paper comprising a wet web having the first and second plies 10, 11. The wet web is flat with no creping.

At step S3, the wet web is dried using a series of drying drums to form a sheet of paper.

At step S4, the dried sheet is rolled onto a bobbin, for storage and/or transportation.

The dried sheet is then used as a plug wrap and/or tipping paper for smoking articles, e.g. cigarettes, made using a conventional cigarette manufacturing machine. The main structural difference between the resulting cigarettes and conventional cigarettes is the composition of the plug wrap and/or tipping paper.

Claims

1. A plug wrap or tipping paper for a smoking article, comprising:

a sheet formed from first and second plies, the first ply comprising fibrous material and the second ply comprising fibrous material, and adsorbent material.

2. The plug wrap or tipping paper according to claim 1, wherein said adsorbent is carbon.

3. The plug wrap or tipping paper according to claim 2, wherein said carbon is activated carbon.

4. The plug wrap or tipping paper according to claim 3, wherein said activated carbon has an activity level (CTC) of 60-130 or 80-120 or approximately 100.

5. The plug wrap or tipping paper according to claim 1, wherein said second ply further comprises flavourant.

6. The plug wrap or tipping paper according to claim 1, wherein said second ply comprises filler material.

7. The plug wrap or tipping paper according to claim 6, wherein said filler material comprises calcium carbonate.

8. The plug wrap or tipping paper according to claim 6, wherein said filler material is present in said second ply in an amount of up to 25 gsm.

9. The plug wrap or tipping paper according to claim 1, wherein the first ply comprises filler material.

10. The plug wrap or tipping paper according to claim 9, wherein said filler material comprises calcium carbonate.

11. The plug wrap or tipping paper according to claim 9, wherein said filler material is present in said first ply in an amount of up to 15 gsm.

12. The plug wrap or tipping paper according to claim 7, wherein the total amount of filler material in said sheet is up to 40 gsm.

13. The plug wrap or tipping paper according to claim 1, wherein the fibrous material is present in said first ply in an amount of up to 20 gsm.

14. The plug wrap or tipping paper according to claim 1, wherein the total amount of fibrous material in said sheet is up to 60 gsm.

15. The plug wrap or tipping paper according to claim 1, wherein the total amount of fibrous material in said sheet is at least 17 gsm.

16. The plug wrap or tipping paper according to claim 1, wherein the thickness of the plug wrap or tipping paper is at least 45 p.m.

17. The plug wrap or tipping paper according to claim 1, wherein the thickness of the plug wrap or tipping paper is up to 250 pm.

18. The plug wrap or tipping paper according to claim 1, wherein said second ply comprises diluent.

19. The plug wrap or tipping paper according to claim 1, wherein said plies are combined to form said single sheet while at least one of the plies is in the wet stage of formation prior to drying.

20. The plug wrap or tipping paper according to claim 19, wherein the plies are combined while both of said plies are in the wet stage of formation prior to drying.

21. A filter element, comprising:

a filter rod; and
a plug wrap enwrapping said filter rod, wherein said plug wrap is a sheet formed from first and second plies, wherein the first ply comprises fibrous material and the second ply comprises fibrous material, and adsorbent material.

22. A smoking article, comprising:

a wrapped rod of smoking material; and
a filter element that comprises a filter rod and a plug wrap enwrapping said filter rod, wherein said plug wrap is a sheet formed from first and second plies, wherein the first ply comprises fibrous material and the second ply comprises fibrous material, and adsorbent material.

23. The smoking article according to claim 22, wherein said second ply of said plug wrap is located on the filter rod side of said plug wrap.

24. A smoking article, comprising:

a wrapped rod of smoking material; and
a filter element attached to said rod of smoking material by means of a tipping paper, wherein said tipping paper is a sheet of paper formed from first and second plies, wherein the first ply comprises fibrous material and the second ply comprises fibrous material and adsorbent material.

25. The smoking article according to claim 24, wherein said second ply of said tipping paper is located on the filter element side of said tipping paper.

26. The smoking article according to claim 24, wherein said filter element comprises a filter rod enwrapped in a plug wrap, said plug wrap being located between said filter rod and said tipping paper.

27. A smoking article, comprising:

a wrapped rod of smoking material;
a filter element that comprises a filter rod and a plug wrap enwrapping said filter rod, wherein said filter element is attached to said rod of smoking material by means of a tipping paper, wherein each of said plug wrap and said tipping paper is a sheet of paper formed from a first ply and a second ply, wherein the first ply comprises fibrous material and the second ply comprises fibrous material and adsorbent material.

28. The smoking article according to claim 22 formed as a cigarette.

29. A method of making a plug wrap or tipping paper for a smoking article, the method comprising:

combining a first ply comprising fibrous material and a second ply comprising fibrous material and adsorbent material to form a two-ply sheet.

30. The method according to claim 29, further comprising combining said first ply and said second ply while at least one of said first ply and said second ply is still in the wet stage of formation prior to drying.

31. The method according to claim 29, further comprising combining said first ply and said second ply using a multi-wire paper making machine.

Patent History

Publication number: 20110180088
Type: Application
Filed: Jan 29, 2009
Publication Date: Jul 28, 2011
Applicant: British American Tobacco (Investments) Limited (London)
Inventors: Nicole Hooper (London), Gordon Grierson (London)
Application Number: 12/936,817

Classifications

Current U.S. Class: Wrapper Or Binder (131/365); Cigarette Paper (162/139); Occupying Plural, Separate, Distinct Zones (131/344)
International Classification: A24D 1/02 (20060101); D21H 27/30 (20060101); A24D 3/06 (20060101);