(19)
(11) EP 1 528 868 B1

(12) EUROPEAN PATENT SPECIFICATION

(45) Mention of the grant of the patent:
04.10.2006 Bulletin 2006/40

(21) Application number: 03712632.3

(22) Date of filing: 25.03.2003
(51) International Patent Classification (IPC): 
A24D 3/06(2006.01)
(86) International application number:
PCT/IN2003/000077
(87) International publication number:
WO 2003/079829 (02.10.2003 Gazette 2003/40)

(54)

BIODEGRADABLE DUAL DENSITY FILTER CIGARETTE

BIOLOGISCH ABBAUBARE FILTERZIGARETTE MIT ZWEI DICHTEN

CIGARETTE DOUBLE DENSITE BIODEGRADABLE, DONT LE BOUT PORTE AUX LEVRES A UNE DENSITE DE TABAC SUPERIEURE


(84) Designated Contracting States:
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PT RO SE SI SK TR

(30) Priority: 26.03.2002 IN DE03192002

(43) Date of publication of application:
11.05.2005 Bulletin 2005/19

(73) Proprietor: Godfrey Phillips India Limited
New Delhi 110 065 (IN)

(72) Inventor:
  • ATINDRANATH, Mittra, Pradip
    West Mumbai 400 080, Maharashtra (IN)

(74) Representative: Glas, Holger 
Maiwald Patentanwalts GmbH, Elisenhof, Elisenstrasse 3
80335 München
80335 München (DE)


(56) References cited: : 
WO-A-00/72706
GB-A- 871 102
GB-A- 739 002
GB-A- 940 059
   
       
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    FIELD OF THE INVENTION



    [0001] The present invention relates to biodegradable dual density cigarette.

    [0002] More specifically the subject invention relates to biodegradable dual density cigarette comprising of two portions, a tobacco rod and butt portion joined to each other longitudinally.

    PRIOR ART



    [0003] The cigarettes presently available in the national and International market can be categorized in two classes namely, plain (non-filter) and filter cigarettes. Cigarettes are made in various sizes in diameter and lengths. The cost of Plain cigarettes is substantially lower. These "plain cigarettes" attract smokers of two types - "Bidi smokers wanting to upgrade themselves "and" filter cigarette smoker opting for low cost cigarettes".

    [0004] The non-filter cigarettes have tobacco with normal density throughout the length of the cigarette. Often the loose tobacco particles enter the mouth of the smoker due to the absence of a filter. The Non-filter cigarette often turns soggy at the smoking end due to constant contact with the smoker's mouth. Besides, due to the relatively loose packing density of the tobacco and loss of tobacco particles from the nonsmoking end, the cigarette loses its stiffness.

    [0005] Filter cigarettes contain tobacco of normal density along with synthetic filters. The filter plug in a filter cigarette comprises of fibrous material attached to a normal density tobacco rod. The fibrous material can be cellulose, acetate tow, polypropylene tow, or any of the other known kind of synthetic fibrous material. These filter cigarettes are non-biodegradable, and require special cigarette making equipment and additionally these cigarettes are more expensive than non-filter cigarette.

    [0006] U.S. Patent Application No. 09/988,828 teaches about a filter cigarette with tobacco filter in which the tobacco strand enclosed by a cigarette paper. The tobacco used is manufactured without using medium cut roll stem and without reconstituted tobacco with a width cut of 0.3 to 0.6 mm and the filter has a tobacco packing density of 350 to 400 g/cm3.

    [0007] EP 1250 854 A1 describes a poison-reduced cigarette includes adding hydrate of double salt of ferroso-ferric chloride into tobacco and cigarette filter to react with nicotine to form salt which will not be absorbed by the mucous membranes in the smoker's respiratory system for minimizing nicotine poison and for enhancing the smoker's health.

    [0008] EP 1032282 describes a filter for tobacco products, in particular cigarettes, is made of a cellulose nonwoven fabric produced by an air-laid process and spirally rolled.

    [0009] EP 1032283 describes a filter cigarette comprising a biodegradable filter and a tobacco strand surrounded by cigarette paper, a non-woven air-laid cellulose filter with a normal retention capacity and a filter ventilation area extending in a peripheral direction. The filter cigarette has the combination of features. The filter has a condensate retention capacity of 40-60%; the non-woven cellulose is non-crimped, the nicotine/tobacco strand condensate yield ratio lies between 0,6 and 0,9 (nicotine *10/condensate), the apparent density of the tobacco mixture of the tobacco strand ranges from 200 to 250mg/ml, the tobacco strand drag is between 45 and 65 mmw WS when measured in an enclosed form, air permeability of the cigarette paper is 20-50 CORESTA units and the filter ventilation degree is 15-50%.

    [0010] WO 01/58290 A1 discloses a cigarette filter for easily removing harmful materials like nicotine an tar from cigarette smoke. During inhalation, the filter can filter harmful ingredients such as nicotine and tar included in cigarette smoke, through a front filter, a mugwort-impregnated filtering-net, a diffusing body, a pine resin-impregnated filtering-net and then a back filter. Additionally, the filter which incorporates the mugwort and the pine resin therein thus is helpful in preserving the health of the smoker, as well as allowing the smoker to feel normal during inhalation, which results from the aromatic properties of the mugwort and the pine resin impregnated into filtering-nets present within the filter.

    [0011] WO 00/72706 discloses a filter cigarette with a tobacco filter.

    [0012] The filters of cigarettes designed to filter harmful materials, such as nicotine and tar, are provided at one end of the cigarette. Such filters are typically classified into several types as follows: That is, the conventional fitters of the cigarettes are classified according to their structure into a single filter consisting of one integrated filter, a double filter formed by a linear arrangement of two filter segments, and a multiples filter formed by the linear arrangement of a plurality of different kinds of filter segments. The filters are also classified according to the material of the filters into a fiber filter, a chemical granule-laden filter, and a carbon granule-laden filter. In the prior art, fiber filters allow hazardous materials included in the cigarette smoke to simply pass through their fibrous matrix, and thus a large effect cannot be expected. However, fiber filters, particularly those laden with carbon or chemical granules for removing nicotine and tar, have been most preferably and widely used as filters for cigarettes.

    [0013] Conventionally a cigarrette rod making machine employs a distributor which delivers fragmentized particles of tobacco leaves, fragmentized sheets of reconstituted tobacco and/or fragments of artificial tobacco to a stream building zone wherein the particles from a continuous stream. Such stream contains surplus of fibrous material and is converted into a continuous rod during travel with a conveyor past a trimming or equalizing device which removes the surplus. The resulting rod (also called filler) is thereupon condensed and draped into a web of cigarette paper or other suitable wrapping material to form with the weeb a cigarette rod which is subdivided (e.g., by a conventional cutoff) into sections of unit length or multiple unit length. The thus obtained cigarettes are delivered to storage, toa packing machine or to a filter tipping machine. Certain types of filter rod sections are or can be produced in a similar manner except that the fibrous material which forms the stream is a substance which intercepts certain presumably harmful ingredients of tobacco smoke when it constitutes the rod-shaped component of the filter mouthpiece in filter cigarette.

    [0014] The object of the present invention is to provide the smoker a filter cigarette having a filter portion which is biodegradable that substantially reduces the tar and nicotine elements and having higher chloride contents.

    [0015] The object of the present invention is to provide the smoker a filter cigarette which is at the same time inexpensive and environment friendly.

    [0016] Yet another object of the present invention is to provide a naturally biodegradable cigarette having a smoke delivery profile comparable to the synthetic filter cigarette.

    [0017] Further object of the present invention is to give satisfaction comparable to that of the conventional filter cigarette without actually having synthetic filter in the cigarette.

    [0018] The present invention provides a biodegradable, environmental friendly, cost effective filter cigarette which eliminates health hazards.

    SUMMARY OF THE INVENTION



    [0019] Accordingly the present invention relates to a biodegradable dual-density cigarette comprising of a rod of tobacco of predetermined length wrapped in cigarette paper wherein the tobacco content are packed at high density at the smoking end of a predetermined length and normal density for the remaining length up to the opposite end.

    [0020] The tobacco content at the said high density end primarily includes mixtures of cut and rolled stem (CRS), but can also include mixtures of graded tobacco, reconstituted tobacco, dust with binders or natural materials.

    [0021] The normal density of such rod is in the range of 225 mg/cc to 280 mg/cc while the high density of such rod is at least 280 mg/cc.

    [0022] The length ratio of normal and high density of said tobacco rod is 5:1 and is configured so as to maintain the desired smoke delivery profile. The high-density end of the said cigarette is wrapped with porus paper of a different colour for the identification of the smoking high density end of the cigarette by the user.

    [0023] Accordingly the present invention relates to a biodegradable dual density cigarette comprising a filler or tobacco rod and butt portion joined to each other longitudinally in a ratio of 5:1 wherein the tobacco rod is a blend of tobacco wrapped in a cigarette paper at a pressure drop of 22 to 50 mm of water column, the butt portion comprising atleast cut-roll stem particles of expanded fibres of density of at least 0.28g/cc wrapped in a porous paper of atleast 100 mm of water gauge.

    [0024] Further described herein, without being claimed, is a process for manufacturing of biodegradable dual densities cigarette comprising the steps of :

    subjecting the stem of the tobacco leaf to a conventional conditioning process for 10 to 20 minutes at 30-40° C. to quench the moisture uniformly;

    passing the said quenched stem through conditioning tunnel or through a flatner or a roller to flatten the stem;

    cutting the stem into small particles of the size 30 to 180 cpi;

    cutting the small particles through an expansion heated tunnel at a temperature of 100 to 103°C for a period of 20 to 30 seconds;

    passing the said particles through a drier and a classifier to obtain a cut roll stem (CRS);

    cooling the CRS at room temperature by storing in boxes rolled humidifier;

    encapsulating the cooled cut rolled stem in a filter wrapping paper to obtain the filter butt;

    processing the filler or tobacco end with tobacco in the conventional manner,

    joining the butt portion in the conventional manner to obtain the biodegradable filler cigarette.



    [0025] The subject invention can better be understood with reference to the accompanying drawings. However, the same are for illustrative purposes and should not be construed to restrict the scope of the invention.

    BRIEF DESCRIPTION OF THE DRAWINGS



    [0026] 

    Figure 1 illustrates a dual density cigarette having normal density tobacco at one end and high-density tobacco at other end. The length ratio of normal and high density can be configured so to maintain the expected smoke delivery profile.


    Detailed description of the invention:



    [0027] The present invention provides for enhancement of smoke delivery profile comparable to normal synthetic filter cigarette as well as results in substantial reduction of tar and nicotine. Due the high density tobacco at the mouth end the sogginess of tobacco when put into the mouth and the entrance of loose tobacco particles entering into the mouth is also avoided.

    [0028] The cigarette is 100% biodegradable and is cost effective since the conventional machines can be used.

    [0029] This cigarette is to be smoked through high-density end and this high density tobacco portion is tipped with porous cork tipping paper of different colour for identification to enable the consumer to know that tipped portion of the cigarette is to be put in the mouth.

    [0030] High-density tobacco rods can be manufactured using tobacco material such as cut and rolled stem, graded tobacco, reconstituted tobacco, tobacco dust with binders as well as various combination of above or natural materials.

    [0031] Density of such rod may be selected as per individual product need. Normally the density selected are at least 280 mg/cc. Figure 1 shows that the tobacco or filler rod (1) is a blend of tobacco wrapped in a cigarette paper at a pressure drop of 22 to 50 mm of water column. The filler rod (1) is filled with blend of tobacco comprising 75 to 85 % of lamina and 15 to 25% of the expanded stem fibres or cutt-roll stem. The lamina is normal density tobacco of 4-6 cc/gm at the rate of 12.5% oven volatile preferably 5-6 cc/gm at the rate of 12.5% oven volatile. The butt portion (2) comprising atleast cut-roll stem particles of expanded fibres of the density of at least 0.28/cc wrapped in a porous paper of atleast 100 mm of water gauge. The expanded stem is 4-7 cc/gm at the rate of 12.5% oven volatile, preferably 6-7 cc/gm at the rate of 12.5% oven volatile. The pressure drop in the tobacco rod is 5-9 water column per mm. of filler end while the pressure drop in the butt end is 3-4 water column per mm. The stem portion is the mid ribb of tobacco plant leaf having lower nicotinic content and higher cloride content.

    [0032] Normal and high-density tobacco rods are manufactured on any conventional cigarette making machine using normal cigarette paper as wrapper for the rod. The stem of the tobacco leaf is subjected to a conventional conditioning process for 10 to 20 minutes at 30-40° C to quench the moisture uniformly. The quenched stem is passed through conditioning tunnel or through a flatner or a roller to flaten the stem. The stem is then cut into small particles of the size 30 to 180 cpi. The small particles are cut through an expansion heated tunnel at a temperature of 100 to 103° C for a period of 20 to 30 seconds. The particles are passed through a drier and a classifier to obtain a cut roll stem (CRS). The CRS are cooled at room temperature by storing in boxes rolled humidifier. The cooled cut rolled stem are encapsulated in a filter wrapping paper to obtain the filter butt;.

    [0033] The filler or tobacco rods are made to required length are then supplied to assembler, the purpose of this unit to assemble the normal and high density tobacco filter butts in the ratio of 5:1.

    [0034] The assembler further cuts the high-density rods in suitable pieces normally 4 to 6 pieces called "Plugs" but other combination are also possible. This is followed by assembly of these "plugs" with the normal tobacco rod and over tipping with the tipping paper of suitable width, size and colour. The tipping paper or plug wrap can either be normal or relatively high porous to give required smoke delivery values.

    [0035] This specially made dual density cigarette is capable of delivery of smoke profile comparable to any other conventional filters as is evident from the test results.

    [0036] White particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in art that various other changes and modifications can be made without departing from the scope of the invention, as defined by the appended claims.

    [0037] The following table shows the typical example of the property of the butt end:
      AVERAGE MINIMUM MAXIMUM
    MOISTURE 10.03 9.10 10.80
    NICOTINE 0.73 0.22 1.34
    TRS 10.87 2.61 20.21
    CHLORIDE 2.70 1.28 3.59


    [0038] The following table shows the property of the filler or tobacco rod:
      AVERAGE MINIMUM MAXIMUM
    MOISTURE 11.79 11.00 12.50
    NICOTINE 1.82 1.63 2.00
    TRS 14.60 12.15 17.12
    CHLORIDE 0.72 0.49 0.96


    [0039] It is clear that the moisture nicotinic content are less in the butt end while TRS and cloride content are more in the but end as compared to the filler end.

    Analytical tests



    [0040] A number of analytical tests were conducted to compare the tar and nicotine content of the non-filter cigarettes, filter cigarettes and dual density cigarettes. The three analytical tables are as given below:

    Table 1 comprises of 3 sub-tables showing the density trend of micro plain cigarettes (Table 1A), Plain and regular filter type cigarettes (Table 1B) and King Size Brands (Table 1C).

    The Tables 1A, 1B and 1C show the comparative tobacco density that exists in different brands of cigarette having a standard length of 59 mm. The data is taken for two years i.e. for the years 2000 and 2001. the figures show that the average density of tobacco in micro plain brands (Table 1A), filter size brands (Table 1 B) and the king size brands (Table 1C) ranges betwen 232 mg/cc and 264 mg/cc.

    The Table 2 features the analytical data showing the comparison of Tar and Nicotine in the non-filter and dual density cigarettes. The analytical data reveals that the Dual Density Cigarettes shows lesser value of the tar & nicotine as compared with the non-filter cigarettes of same lengths.

    Table 3 shows the comparison of "tar" and "nicotine" yield obtained from the conventional filter tipped cigarettes, the dual density cigarettes fitted with present invention and the non-filter plain cigarette. The table reveals that the quality of smoke delivery of dual density cigarette is comparable with the filter cigarette. The tar content of the smoke from the dual density cigarette with a circumference of 24.44 mm is slightly higher than the tar content in the filter cigarette with the circumference of 24.46 mm.

    Table 1A
    DENSITY TREND OF MICRO PLAIN BRANDS
    BRANDS 59 mm Brands Month Year JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC AVG MIN MAX
    Cav Super 2001 259       261 254 253     251 252   256 244 266
      2000 256 259   257 250 251 266 254 244   260        
    FS Super 2001       245 272 257 252 255 250 258 250 250 254 245 272
      2000               250 256            
    RW Super 2001 255   254 264 260 246 253 233 249 248 255 271 253 233 278
      2000 258 241 254 278 251 266 262 243 245 245 247 242      
    Bristol Std 2001   274             271     246 264 246 274
      2000                              
    Capstan Super 2001           246           233 240 233 246
      2000                              
    SCISSORS STANDARD 2001           268     260       258 247 268
      2000   247                          
    Table 1B
    DENSITY TREND OF PLAIN & REGULAR FILTER SIZE BRANDS
    BRANDS Month Year JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC AVG MIN MAX
    CVGL- 69 mm. 2001   261 267   253 257 260 267 255 263 263 263 260 247 267
      2000 263 247 265 257 261       250 261 265        
    RW Plain - 67 mm 2001     270 273     245 272   249 249 251 252 242 273
      2000 245 243 247 244 251 245 253 255 255   244 242      
    Scissors Plain -68 mm 2001 245 248       238         247   245 238 248
      2000                              
    FS Special 2001 254 259 254 257 255 263 267 278 262 260 262 266 260 254 278
      2000 254 255 254 257 255 262 255 267 264 255 270 258      
    FS Premier 2001 260 260 257 259 256 258 256 271 260 261 264 262 260 249 271
      2000   254   261 257 260 249 265 257 264 267 252      
    RW Flake 2001 257 253 254 261 261 265 265   266 252 258 267 258 244 267
      2000 251 255 244 258 255 264 250 255 265 257 265 263      
    GF Premium 2001   250 263 254   254 255     256 261 257 258 250 266
      2000   256   263 266   261 257     262        
    Wills Flake 2001     256     255 262       265   261 255 274
      2000       256     264 274     256        
    Table 1C
    DENSITY TREND OF KING SIZE BRANDS
    BRANDS Month Year JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC AVG MIN MAX
    FS Kings 2001 248 246 242 255 251 251 255 266 257 253 252 255 252 242 266
      2000 250 247 254 248 246 252 255 255 257 249 257 248      
    GF kings 2001   251 249 247   249 249     253   260 251 244 264
      2000   252 257   252 244 244 248     251        
    Classic Kings 2001   264       244     252       249 244 255
      2000   247   255       244     251        
    BH Sp 2001       242   233     236       242 233 249
      2000     249         246     245        
    555 Kings 2001                 244       244 243 245
      2000       243             245        
    Marlboro 2001       225   233     235       232 225 235
    Lights 2000   235                          


    Table 3
    Smoke parameters 59 x 24.5 PI. 69 x 24.5 x 11 mm CRS 59 x 24.5 x 11 mm CA
    ISO Tar 16.6 15.4 14.9
    Nicotine 1.49 1.27 1.27
    Circumference 24.57 24.44 24.46



    Claims

    1. A biodegradable dual density cigarette composing a tobacco or filler rod and butt portion joined to each other longitudinally in a ratio of 5:1 wherein the tobacco rod is a blend cf tobacco wrapped in a cigarette paper at a pressure drop of 22 to 50 mm of water column, the butt portion comprising at least cut-roll stem particles of expanded fibres of density of at least 0.28 gm/cc wrapped in a porous paper of at least 100 mm water column.
     
    2. A biodegradable dual density cigarette, according to claim 1, wherein the blend of tobacco comprises 75 to 85 % of lamina and 15 to 25% of the expanded stem fibres (CRS).
     
    3. A biodegradable dual density cigarette, according to claim 2, wherein the lamina is normal density tobacco of 4-6 cc/gm at the rate of 12.5% oven volatile preferably 5-6 cc/gm, at the rate of 12.5% oven volatile.
     
    4. A biodegradable dual density cigarette, according to claim 2, wherein the expanded stem is 4-7 cc/gm at the rate of 12.5% oven volatile preferably 6-7 cc/gm at the rate of 12.5% oven volatile.
     
    5. A biodegradable dual density cigarette, according to claim 1, wherein the pressure drop in the filler or tobacco rod is 5-9 water column per mm. of filler and while the pressure drop in the butt portion is 3-4 water column per mm.
     
    6. A biodegradable dual density cigarette, according to claim 2, wherein the expanded stem is the mid rib of tobacco plant leaf having lower nicotinic content and higher chloride content.
     
    7. A biodegradable dual density cigarette, according to claim 2, wherein the butt portion is wrapped in a porous paper having a resistance to burning compared to the cigarette paper of the filler rod.
     
    8. A biodegradable dual density cigarette, according to claim 2, wherein the said butt portion comprising a mixture of tobacco fibre, tobacco dust with binders and lower grade of tobacco.
     


    Ansprüche

    1. Biologisch abbaubare Zigarette mit zwei Dichten umfassend eine Tabak- oder Füllstückstange und einen Kippenteil, die in Längsrichtung in einem Verhältnis von 5:1 miteinander verbunden sind, wobei die Tabakstange eine Tabakmischung umfasst, die in ein Zigarettenpapier bei einem Druckabfall von 22 bis 50 mm Wassersäule gewickelt ist, wobei der Kippenteil zumindest geschnittene und gewalzte Stengelteilchen expandierter Fasern einer Dichte von mindestens 0.28 g/cm3, die in poröses Papier von mindestens 100 mm Wassersäule gewickelt sind, umfasst.
     
    2. Biologisch abbaubare Zigarette mit zwei Dichten gemäß Anspruch 1, wobei die Tabakmischung 75 bis 85 % Blattmaterial und 15 bis 25 % der expandierten Stengelfasern (CRS) umfasst.
     
    3. Biologisch abbaubare Zigarette mit zwei Dichten gemäß Anspruch 2, wobei das Blattmaterial normal dichter Tabak von 4 bis 6 cm3/g bei einer Rate von 12.5 % ofenflüchtigen Stoffen, vorzugsweise von 5 bis 6 cm3/g bei einer Rate von 12.5 % ofenflüchtigen Stoffen ist.
     
    4. Biologisch abbaubare Zigarette mit zwei Dichten gemäß Anspruch 2, wobei der expandierte Stengel 4 bis 7 cm3/g bei einer Rate von 12.5 % ofenflüchtigen Stoffen, vorzugsweise 6 bis 7 cm3/g bei der Rate von 12.5 % ofenflüchtigen Stoffen ist.
     
    5. Biologisch abbaubare Zigarette mit zwei Dichten gemäß Anspruch 1, wobei der Druckabfall in der Füllstück- oder Tabakstange 5 bis 9 mm Wassersäule pro mm Füllstück beträgt, während der Druckabfall in dem Kippenteil 3 bis 4 mm Wassersäule pro mm beträgt.
     
    6. Biologisch abbaubare Zigarette mit zwei Dichten nach Anspruch 2, wobei der expandierte Stengel die Mittelrippen des Tabakpflanzenblattes mit einem geringeren Nikotingehalt und einem höheren Chloridgehalt aufweist.
     
    7. Biologisch abbaubare Zigarette mit zwei Dichten nach Anspruch 2, wobei der Kippenteil in ein poröses Papier eingewickelt ist, welches im Vergleich zum Zigarettenpapier der Füllstückstange einen Widerstand gegenüber dem Verbrennen aufweist.
     
    8. Biologisch abbaubare Zigarette mit zwei Dichten nach Anspruch 2, wobei der Kippenteil eine Mischung aus Tabakfaser, Tabakstaub mit Bindemitteln und Tabak geringerer Güte umfasst.
     


    Revendications

    1. Cigarette de densité double biodégradable comprenant un boudin continu de tabac ou d'apport et une portion de butée, liés l'un à l'autre dans le sens de la longueur dans une proportion de 5 pour 1, dans laquelle le boudin continu de tabac est un mélange de tabac enveloppé dans un papier à cigarettes avec une chute de pression de 22 à 50 mm de colonne d'eau, la portion de butée comprenant au moins des particules à base de côtes laminées et hachées de fibres expansées d'une densité d'au moins 0,28g/cm3 enveloppées dans un papier poreux avec au moins 100 mm de colonne d'eau.
     
    2. Cigarette de densité double biodégradable, selon la revendication 1, dans laquelle le mélange de tabac comprend entre 75 et 85% de parenchyme et 15 à 25% de fibres expansées à base de côtes (CRS).
     
    3. Cigarette de densité double biodégradable, selon la revendication 2, dans laquelle le parenchyme est un tabac de densité normale de 4-6 cm3/g avec un taux de 12,5% volatile dans un four et de préférence 5-6 cm3/g avec un taux de 12,5% volatile dans un four.
     
    4. Cigarette de densité double biodégradable, selon la revendication 2, dans laquelle la côte expansée est de 4-7 cm3/g avec un taux de 12,5% volatile dans un four et de préférence 6-7 cm3/g avec un taux de 12,5% volatile dans un four.
     
    5. Cigarette de densité double biodégradable, selon la revendication 1, dans laquelle la chute de pression dans la boudin continu de tabac ou d'apport est de 5-9 mm de colonne d'eau par mm d'apport alors que la chute de pression dans la portion de butée est de 3-4 mm de colonne d'eau par mm.
     
    6. Cigarette de densité double biodégradable, selon la revendication 2, dans laquelle la côte expansée est la demi nervure de la feuille de la plante de tabac présentant une teneur en nicotine plus faible et une teneur en chlorure plus élevée.
     
    7. Cigarette de double densité biodégradable, selon la revendication 2, dans laquelle la portion de butée est enveloppée dans un papier poreux présentant une résistance à la combustion par rapport au papier à cigarettes du boudin continu d'apport.
     
    8. Cigarette de double densité biodégradable, selon la revendication 2, dans laquelle ladite portion de butée comprend un mélange de fibres de tabac, de poussières de tabac avec des liants et une qualité de tabac inférieure.
     




    Drawing