US3547009A - Method of making filters for cigarettes - Google Patents
Method of making filters for cigarettes Download PDFInfo
- Publication number
- US3547009A US3547009A US752966A US3547009DA US3547009A US 3547009 A US3547009 A US 3547009A US 752966 A US752966 A US 752966A US 3547009D A US3547009D A US 3547009DA US 3547009 A US3547009 A US 3547009A
- Authority
- US
- United States
- Prior art keywords
- filter
- stubs
- stub
- elements
- length
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- A—HUMAN NECESSITIES
- A24—TOBACCO; CIGARS; CIGARETTES; SIMULATED SMOKING DEVICES; SMOKERS' REQUISITES
- A24D—CIGARS; CIGARETTES; TOBACCO SMOKE FILTERS; MOUTHPIECES FOR CIGARS OR CIGARETTES; MANUFACTURE OF TOBACCO SMOKE FILTERS OR MOUTHPIECES
- A24D3/00—Tobacco smoke filters, e.g. filter-tips, filtering inserts; Filters specially adapted for simulated smoking devices; Mouthpieces for cigars or cigarettes
- A24D3/02—Manufacture of tobacco smoke filters
- A24D3/0204—Preliminary operations before the filter rod forming process, e.g. crimping, blooming
- A24D3/0212—Applying additives to filter materials
- A24D3/0225—Applying additives to filter materials with solid additives, e.g. incorporation of a granular product
Definitions
- Such filters can be made by arranging 'stubs, i.e. cylindrical portions of fibrous or other air-permeable material, at spaced intervals on a paper strip which is folded to U-cross section, and feeding particulate material in loose form into the pockets formed by the bowed paper strip' and the opposite end faces of neighboring stubs, after which the paper strip is folded into tubular form about the' stubs and particulate material. Difficulty is, however, experienced in ensuring that enough particulate material is containedbetween two stubs to ensure that when the final-filter cigarette is'smoked, all the smoke passes through the particulate filtering material and none bypasses it. i
- a method of making a smoke-filtering rod including the step of assemblingtwo smoke-permeable cylindrical elements to be embraced in a tubular wrapping together with particulate, filtering material between the two elements whereby the material is enclosed in a space defined between the two elements within the wrapping and including the step of causing the two elements to be relatively displaced to reduce the volume of said space and thereby increase the degree to which the material packs the space.
- the two elements can on the one hand be filter stubs and I the method can include moving one stub towards the other to be displaced inwardly of an end of the wrapping to define a FIG. 4 represents an assemblage of two cigarette lengths the cylindrical paper wrapper 6 of the filterZ, are firmly.
- the outer stub 4 although held in position by the wrapper 6, is not stuck to it at this stage but can be moved endwise within it, and in accordance with the invention is moved inwardly towards the inner stub 5, thus reducing the space between the two stubs and ensuring that this space is substantially entirely filled by the loose particulate material 7. Asa result of this inward movement a hollow recess 8 is left at the end of the filter.
- FIGS. 2AC An alternative method is illustratedin FIGS. 2AC.
- outer stub 4 in this instance is initially longer than required, and when it has been moved inwardly as shown in FIG. 28, it is trimmed by being cut through along the line C-C. This reduces the stub to the length required and-also produces a flush end as illustrated in FIG. 2C.
- the filter cigarettes may be produced by first producing an assemblage consisting of a double-length filter between two cigarette lengths as illustrated in FIG. 4. This assemblage is subdivided by cutting through the central double-length stub 4A, which divides into The two elements can on the other hand be a filter stub and a wrapped tobacco rod whereby a filter cigarette is produced.
- the method can include coating the inner face of the wrapping with adhesive of anature such as to permit movement of a smoke-permeable element within the wrapping and to be capable of subsequently being caused to secure the stubs to the tube.
- the adhesive can be heat-scalable and include the step of heating the rod to seal the adhesive.
- the invention also includes a method of making filter cigarettes comprising subdividing an assemblage consisting of a double-length filter between and joined to two cigarette lengths and using any of the methods described above to form the filter.
- This method of making filter cigarettes can include fonning the double length filter to comprise .three filter stubs spaced apart within a tube the two spaces between them containing particulate material and the central. stub of the three being of at least double the length required in the endmost stub of the filter of a cigarette and moving the two endmost stubs inwardly towards each' other. It can also include trimming the ends to present flush end faces or the stubs can be moved inwardly of the ends of their'wrapping and the-filter cigarettes can be formed to have a hollowspace between the tobacco and the adjacent filter stub. 1
- the invention extends to cigarette filters and filter cigarettes produced by the methods described.
- FIGS. 1A and 18 represent two stages inthe production of a filter cigarette
- FIGS. 2A, 2B and 2C represent three stages in the production of a filter cigarette by an alternative method
- FIGS. 3A and 38 represent two stages in the production of a filter
- FIGS. 3A and B illustrate a further example in which the endwise displacement of stubs is effected at an earlier stage of manufacture, i.e. before a double-length filter is joined to two cigarette lengths as shown in FIG. 4.
- FIG. 3A shows a doublelength filter comprising a double-length stub 4A (which eventually will divide into two outer stubs 4) and two stubs 5A, the latter being a little longer than will be required in the final product.
- the two stubs 5A are pushed inwardly towards each other within the tube 6, as shown in FIG. 3B, and are then trimmed by cutting at the lines C-C.
- single-length filters can be treated in a similar way to that just described in relation to a double-length filter. That is, both stubs in the single-length filter can be moved towards each other and the filter trimmed at both ends, or only one stub could be moved towards the other.
- the stubs are in such a case initially of a suitable length to allow for the trimming.
- the tube enclosing the stubs should be of sufficiently rigid material to enable a firm filter cigarette to be produced.
- the method in which single-length instead of doublelength filters are treated as described above could be modified by omitting the step of trimming ofa hollow chamber is desired between the cigarette and its neighbouring stub.
- the tube 6 should preferably be coated with an adhesive material which can be made effective after the stubs have been moved inwardly as described, e.g. a heat-sealing material may be used which will finally secure the stubto the inner surface of the tube and prevent further movement.
- an adhesive material which can be made effective after the stubs have been moved inwardly as described, e.g. a heat-sealing material may be used which will finally secure the stubto the inner surface of the tube and prevent further movement.
- a method of making a smoke-filtering rod comprising assembling two smoke-permeable cylindrical elements with particulate filtering material between the two elements in a tubular wrapping having an adhesive coating on the inner face thereof whereby the material is enclosed in a space defined between the two elements within the wrapping, relatively displacing the two elements towards each other to reduce the volume of said space and thereby increase the degree to which said filtering material packs the space, and causing said adhesive to secure the elements to the tube.
- a method according to claim 1 wherein the adhesive is heatsealable and said step of causing said adhesive to secure the elements to the tube comprises heating the rod to seal the adhesive following movement of the elements.
- a method according to claim 1 wherein the two elements are filter stubs, one of said stubs being relatively displaced inwardly of an end of the wrapping towards the other stub whereby a recessed end space is fonned.
- a method of making a double-length smoke-filtering rod comprising assembling three cylindrical filter stubs spaced apart within a tube with particulate filtering material contained in the two spaced between the three stubs, the central stub of the three being at least double the predetermined length of the endmost stub of the filter of a cigarette, relatively displacing the two stubs at opposite ends of the wrapping towards the central stub to reduce the volume of said spaces and thereby increase the degree to which said filtering material packs the two spaces and recessed end spaces are formed and trimming the ends to present flush end faces.
- a method of making a smoke-filtering rod comprising assembling two smoke-penneable cylindrical elements with particulate filtering material between the two elements in a space defined between the two elements within the wrapping, one of said elements being longer than is required in the final smokefiltering rod, relatively displacing said longer element inwardly of an end of the wrapping towards the other elements to reduce the volume of said space and thereby increase the degree to which said filtering materialf packs the space whereby a recessed end space is formed, and subsequently cutting through said longer element and its enclosing wrapping to trim the filter to reduce the length of the stub to a predetermined length and to produce a neat nonrecessed end face.
- a method of making a double-length smoke-filtering rod comprising assembling three cylindrical filter stubs spaced apart within a tubular wrapping a tubular wrapping with particulate filtering material contained in the two spaced between the three stubs, the central stub of the three being at least double the predetermined length of the endmost stub of the filter of a cigarette and said wrapping having an adhesive coating on the inner face thereof, relatively displacing the two stubs at opposite ends of the tube towards the central tube to reduce the volume of said spaces and thereby increase the degree to which said filtering material packs the two spaces, and causing said adhesive to secure the elements to the tube.
Landscapes
- Cigarettes, Filters, And Manufacturing Of Filters (AREA)
- Manufacturing Of Cigar And Cigarette Tobacco (AREA)
Description
United States Patent [54] METHOD OF MAKING FILTERS FOR CIGARETTES 7 Claims, 8 Drawing Figs.
[52] U.S.Cl 93/1, 13l/ll, 131/61 [51] lnt.Cl....; 831d [50] Field of Search 93/1 0; 131/209, l 1,61A
[56] References Cited UNITED STATES PATENTS 3,354,887 11/1967 Hall Primary Examiner-Bernard Stickney Attorney-Craig, Antonelli, Stewart & Hill ABSTRACT: Making filter cigarettes incorporating particulate filtering material enclosed in a compartment by a method including the step of pushing a filter stub endwise towards the.
tobacco rod to pack the filtering material better. Alternative ways are described.
PATENIED-BEII! slam- INVENTOR ATTORNEY METHOD OF MAKING FILTERS FQR CIGARE'I'IES This invention concerns improvements in or relating to filters for cigarettes, which-filters include particulate filtering material; the term cigarettes" being understood to include cigars, cigarillos and other smokable articles.
Such filters can be made by arranging 'stubs, i.e. cylindrical portions of fibrous or other air-permeable material, at spaced intervals on a paper strip which is folded to U-cross section, and feeding particulate material in loose form into the pockets formed by the bowed paper strip' and the opposite end faces of neighboring stubs, after which the paper strip is folded into tubular form about the' stubs and particulate material. Difficulty is, however, experienced in ensuring that enough particulate material is containedbetween two stubs to ensure that when the final-filter cigarette is'smoked, all the smoke passes through the particulate filtering material and none bypasses it. i
According to the present invention there is provided a method of making a smoke-filtering rod including the step of assemblingtwo smoke-permeable cylindrical elements to be embraced in a tubular wrapping together with particulate, filtering material between the two elements whereby the material is enclosed in a space defined between the two elements within the wrapping and including the step of causing the two elements to be relatively displaced to reduce the volume of said space and thereby increase the degree to which the material packs the space.
The two elements can on the one hand be filter stubs and I the method can include moving one stub towards the other to be displaced inwardly of an end of the wrapping to define a FIG. 4 represents an assemblage of two cigarette lengths the cylindrical paper wrapper 6 of the filterZ, are firmly.
secured by adhesive to the uniting band 3. However, the outer stub 4, although held in position by the wrapper 6, is not stuck to it at this stage but can be moved endwise within it, and in accordance with the invention is moved inwardly towards the inner stub 5, thus reducing the space between the two stubs and ensuring that this space is substantially entirely filled by the loose particulate material 7. Asa result of this inward movement a hollow recess 8 is left at the end of the filter.
' An alternative method is illustratedin FIGS. 2AC. The
In both the examples described above, the filter cigarettes may be produced by first producing an assemblage consisting of a double-length filter between two cigarette lengths as illustrated in FIG. 4. This assemblage is subdivided by cutting through the central double-length stub 4A, which divides into The two elements can on the other hand be a filter stub and a wrapped tobacco rod whereby a filter cigarette is produced.
The method can include coating the inner face of the wrapping with adhesive of anature such as to permit movement of a smoke-permeable element within the wrapping and to be capable of subsequently being caused to secure the stubs to the tube. The adhesive can be heat-scalable and include the step of heating the rod to seal the adhesive.
The invention also includes a method of making filter cigarettes comprising subdividing an assemblage consisting of a double-length filter between and joined to two cigarette lengths and using any of the methods described above to form the filter. This method of making filter cigarettes can include fonning the double length filter to comprise .three filter stubs spaced apart within a tube the two spaces between them containing particulate material and the central. stub of the three being of at least double the length required in the endmost stub of the filter of a cigarette and moving the two endmost stubs inwardly towards each' other. It can also include trimming the ends to present flush end faces or the stubs can be moved inwardly of the ends of their'wrapping and the-filter cigarettes can be formed to have a hollowspace between the tobacco and the adjacent filter stub. 1
The invention extends to cigarette filters and filter cigarettes produced by the methods described.
' Filter cigarettes and filters and methods of producing them will now be described by way of example with reference to the accompanying diagrammatic drawing, in which:
FIGS. 1A and 18 represent two stages inthe production of a filter cigarette; I
FIGS. 2A, 2B and 2C represent three stages in the production of a filter cigarette by an alternative method;
FIGS. 3A and 38 represent two stages in the production of a filter; and
two outer stubs 4. It is contemplated that the operations described above with reference to FIGS. 1A and B and 2A-C are to be performed immediately or soon after the assemblage as illustrated in FIG. 4 has been subdivided.
FIGS. 3A and B illustrate a further example in which the endwise displacement of stubs is effected at an earlier stage of manufacture, i.e. before a double-length filter is joined to two cigarette lengths as shown in FIG. 4. FIG. 3A shows a doublelength filter comprising a double-length stub 4A (which eventually will divide into two outer stubs 4) and two stubs 5A, the latter being a little longer than will be required in the final product. The two stubs 5A are pushed inwardly towards each other within the tube 6, as shown in FIG. 3B, and are then trimmed by cutting at the lines C-C.
As an alternative, in a case where single-length filters are to be joined to single cigarette lengths, for example by a relatively narrow uniting band, single-length filters can be treated in a similar way to that just described in relation to a double-length filter. That is, both stubs in the single-length filter can be moved towards each other and the filter trimmed at both ends, or only one stub could be moved towards the other. The stubs are in such a case initially of a suitable length to allow for the trimming.
As an alternative to trimming the stub 4 in FIG. 313, it may be preferred in some instances to leave the end of the filter recessed so that in the final filter cigarette there will be a hollowchamber between the cigarette and the stub 5A. If this is done, the tube enclosing the stubs should be of sufficiently rigid material to enable a firm filter cigarette to be produced. Similarly the method in which single-length instead of doublelength filters are treated as described above could be modified by omitting the step of trimming ofa hollow chamber is desired between the cigarette and its neighbouring stub.
In all the examples described above, the tube 6 should preferably be coated with an adhesive material which can be made effective after the stubs have been moved inwardly as described, e.g. a heat-sealing material may be used which will finally secure the stubto the inner surface of the tube and prevent further movement.
I claim:
1. A method of making a smoke-filtering rod comprising assembling two smoke-permeable cylindrical elements with particulate filtering material between the two elements in a tubular wrapping having an adhesive coating on the inner face thereof whereby the material is enclosed in a space defined between the two elements within the wrapping, relatively displacing the two elements towards each other to reduce the volume of said space and thereby increase the degree to which said filtering material packs the space, and causing said adhesive to secure the elements to the tube.
2. A method according to claim 1 wherein the adhesive is heatsealable and said step of causing said adhesive to secure the elements to the tube comprises heating the rod to seal the adhesive following movement of the elements.
3. A method according to claim 1 wherein the two elements are filter stubs, one of said stubs being relatively displaced inwardly of an end of the wrapping towards the other stub whereby a recessed end space is fonned.
4. A method according to claim 3 wherein said one stub which is moved towards the other stub is longer than is required in the final smoke-filtering rod, said method comprising subsequently cutting through said longer stub and its enclosing wrapping to trim the filter to reduce the length of the stub to a predetermined length and to produce a neat, nonrecessed end face.
5. A method of making a double-length smoke-filtering rod comprising assembling three cylindrical filter stubs spaced apart within a tube with particulate filtering material contained in the two spaced between the three stubs, the central stub of the three being at least double the predetermined length of the endmost stub of the filter of a cigarette, relatively displacing the two stubs at opposite ends of the wrapping towards the central stub to reduce the volume of said spaces and thereby increase the degree to which said filtering material packs the two spaces and recessed end spaces are formed and trimming the ends to present flush end faces.
6. A method of making a smoke-filtering rod comprising assembling two smoke-penneable cylindrical elements with particulate filtering material between the two elements in a space defined between the two elements within the wrapping, one of said elements being longer than is required in the final smokefiltering rod, relatively displacing said longer element inwardly of an end of the wrapping towards the other elements to reduce the volume of said space and thereby increase the degree to which said filtering materialf packs the space whereby a recessed end space is formed, and subsequently cutting through said longer element and its enclosing wrapping to trim the filter to reduce the length of the stub to a predetermined length and to produce a neat nonrecessed end face.
7. A method of making a double-length smoke-filtering rod comprising assembling three cylindrical filter stubs spaced apart within a tubular wrapping a tubular wrapping with particulate filtering material contained in the two spaced between the three stubs, the central stub of the three being at least double the predetermined length of the endmost stub of the filter of a cigarette and said wrapping having an adhesive coating on the inner face thereof, relatively displacing the two stubs at opposite ends of the tube towards the central tube to reduce the volume of said spaces and thereby increase the degree to which said filtering material packs the two spaces, and causing said adhesive to secure the elements to the tube.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB38582/67A GB1170174A (en) | 1967-08-22 | 1967-08-22 | Improvements in or relating to Filters for Cigarettes. |
Publications (1)
Publication Number | Publication Date |
---|---|
US3547009A true US3547009A (en) | 1970-12-15 |
Family
ID=10404419
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US752966A Expired - Lifetime US3547009A (en) | 1967-08-22 | 1968-08-15 | Method of making filters for cigarettes |
Country Status (5)
Country | Link |
---|---|
US (1) | US3547009A (en) |
DE (1) | DE1782352B2 (en) |
FR (1) | FR1577720A (en) |
GB (1) | GB1170174A (en) |
IT (1) | IT1036008B (en) |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4038992A (en) * | 1975-09-29 | 1977-08-02 | The Japan Tobacco & Salt Public Corporation | Granular composition for tobacco filter |
US20050115578A1 (en) * | 2001-12-11 | 2005-06-02 | Michael Launstein | Filter, smoking articles containing the same, filter strands and methods and devices for producing filters and smoking articles of this type |
US20060025292A1 (en) * | 2004-07-29 | 2006-02-02 | Brown & Williamson Tobacco Corporation | Producing triple section filters using a dual rod filter maker |
US20060112963A1 (en) * | 2004-11-05 | 2006-06-01 | Philip Morris Usa Inc. | Vertical filter filling machine and process |
US20100175703A1 (en) * | 2001-11-30 | 2010-07-15 | Philip Morris Usa Inc. | Continuous process for impregnating solid adsorbent particles into shaped mirco-cavity fibers |
US20120302416A1 (en) * | 2009-03-19 | 2012-11-29 | R.J. Reynolds Tobacco Company | Method of forming a rod for use in the manufacture of cigarette filters |
US10104906B1 (en) | 2012-09-17 | 2018-10-23 | Tannpapier Gmbh | Mouthpiece lining paper |
US11266175B2 (en) | 2016-12-21 | 2022-03-08 | Philip Morris Products S.A. | Smoking article with extinguishment means |
EP3967159A1 (en) * | 2020-09-10 | 2022-03-16 | Andreas Setzer | Device for filtering smoke |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4174720A (en) * | 1977-04-26 | 1979-11-20 | Liggett Group Inc. | Glue transfer apparatus for cigarette filters |
-
1967
- 1967-08-22 GB GB38582/67A patent/GB1170174A/en not_active Expired
-
1968
- 1968-08-15 US US752966A patent/US3547009A/en not_active Expired - Lifetime
- 1968-08-17 IT IT52854/68A patent/IT1036008B/en active
- 1968-08-20 DE DE1782352A patent/DE1782352B2/en not_active Withdrawn
- 1968-08-22 FR FR1577720D patent/FR1577720A/fr not_active Expired
Cited By (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4038992A (en) * | 1975-09-29 | 1977-08-02 | The Japan Tobacco & Salt Public Corporation | Granular composition for tobacco filter |
US20100175703A1 (en) * | 2001-11-30 | 2010-07-15 | Philip Morris Usa Inc. | Continuous process for impregnating solid adsorbent particles into shaped mirco-cavity fibers |
US20050115578A1 (en) * | 2001-12-11 | 2005-06-02 | Michael Launstein | Filter, smoking articles containing the same, filter strands and methods and devices for producing filters and smoking articles of this type |
US8047977B2 (en) | 2001-12-11 | 2011-11-01 | Philip Morris Usa Inc. | Filter, smoking articles containing the same, filter strands and methods and devices for producing filters and smoking articles of this type |
US20060025292A1 (en) * | 2004-07-29 | 2006-02-02 | Brown & Williamson Tobacco Corporation | Producing triple section filters using a dual rod filter maker |
US20100210437A1 (en) * | 2004-11-05 | 2010-08-19 | Philip Morris Usa Inc. | Vertical filter filling machine and process |
US7713184B2 (en) | 2004-11-05 | 2010-05-11 | Philip Morris Usa Inc. | Vertical filter filling machine and process |
US20090118109A1 (en) * | 2004-11-05 | 2009-05-07 | Philip Morris Usa Inc. | Vertical filter filling machine and process |
US7479099B2 (en) * | 2004-11-05 | 2009-01-20 | Philip Morris Usa Inc. | Vertical filter filling machine and process |
US20060112963A1 (en) * | 2004-11-05 | 2006-06-01 | Philip Morris Usa Inc. | Vertical filter filling machine and process |
US8114002B2 (en) | 2004-11-05 | 2012-02-14 | Philip Morris Usa Inc. | Vertical filter filling machine and process |
US20120302416A1 (en) * | 2009-03-19 | 2012-11-29 | R.J. Reynolds Tobacco Company | Method of forming a rod for use in the manufacture of cigarette filters |
US9247770B2 (en) * | 2009-03-19 | 2016-02-02 | R.J. Reynolds Tobacco Company | Method of forming a rod for use in the manufacture of cigarette filters |
US9486010B2 (en) | 2009-03-19 | 2016-11-08 | R. J. Reynolds Tobacco Company | Apparatus for inserting objects into a filter component of a smoking article |
US10104906B1 (en) | 2012-09-17 | 2018-10-23 | Tannpapier Gmbh | Mouthpiece lining paper |
US11266175B2 (en) | 2016-12-21 | 2022-03-08 | Philip Morris Products S.A. | Smoking article with extinguishment means |
EP3967159A1 (en) * | 2020-09-10 | 2022-03-16 | Andreas Setzer | Device for filtering smoke |
WO2022053597A1 (en) * | 2020-09-10 | 2022-03-17 | Andreas Setzer | Device for filtering smoke |
Also Published As
Publication number | Publication date |
---|---|
GB1170174A (en) | 1969-11-12 |
IT1036008B (en) | 1979-10-30 |
FR1577720A (en) | 1969-08-08 |
DE1782352A1 (en) | 1971-08-12 |
DE1782352B2 (en) | 1978-04-20 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
AU2009321582B2 (en) | Smoking article filter | |
US4064791A (en) | Method and apparatus for making tobacco smoke filter | |
US4649944A (en) | Filter cigarette | |
US3533416A (en) | Tobacco smoke filter | |
US8360074B2 (en) | Smoking article | |
US3547009A (en) | Method of making filters for cigarettes | |
WO1984001272A1 (en) | Filter cigarette | |
EP0202835B1 (en) | Composite cigarettes | |
US3384094A (en) | Manufacture of mouthpiece cigarettes | |
JPS5933350B2 (en) | cigarettes | |
US3602235A (en) | Adjustable filtering device for smoking articles | |
US3625118A (en) | Manufacture of filters for cigarettes or like smoking articles | |
GB2103065A (en) | Ventilated cigarette filter | |
US4328817A (en) | Smoking articles | |
EP0777425B1 (en) | Concentric core filter | |
US4481959A (en) | Filtering means | |
US3524450A (en) | Smokers' articles | |
US4774972A (en) | Ventilated tobacco smoke filter | |
CA1200732A (en) | Smoking article filters | |
GB2118423A (en) | Tobacco smoke filter | |
US4724848A (en) | Smoking article filters | |
GB2101869A (en) | Filtering means | |
US4481954A (en) | Cigarettes | |
US3685527A (en) | Filter construction and method of forming same | |
EP0209319A1 (en) | A filter-tipped tobacco product with spirally applied wrapper, and a method of manufacturing the product |