Abstract:
A wrapper for a smoking article which, when wrapped about a tobacco column, provides improved mainstream smoke taste and sidestream smoke odor subjectives. These objectives are attained by forming a cellulosic sheet containing a small amount, but less than about 2%, of activated carbon having absorbed onto the carbon a volatile flavorant.

Description:
REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part of application Ser. No. 07/656,497, filed Feb. 19, 1991, to issue as U.S. Pat. No. 5,107,864 on Apr. 28, 1992. 
    
    
     SUMMARY OF THE INVENTION 
     This invention provides a regular, reduced sidestream smoke or heavy weight cigarette paper or cigar wrapper which, when fabricated into a cigarette or cigar with a suitable tobacco column, statically burns at an acceptable rate, produces a light-colored, well-formed ash, which clings tightly without premature flaking and delivers both mainstream and sidestream smoke with a subjectively pleasant taste and aroma. More specifically, these desirable taste and aroma properties are achieved when certain defined levels of activated carbon, which contain certain levels of volatile flavors absorbed thereon, are incorporated into the sheet matrix of the cigarette paper or cigar wrapper or are applied to the surface (preferably on the inside-wire side-surface of the cigarette paper) which encloses the tobacco column. Flavors can be absorbed onto all or part of the carbon. Incorporation of the flavor-absorbed carbons into the sheet matrix to give desirable taste and aroma, as well as acceptable cigarette paper appearance, can be accomplished by maintaining a sheet carbon content of less than 2% carbon (preferably 1% or below) with the carbon particle size being such to totally pass through a 200 mesh screen (ASTM E-11 test) and preferably totally through 325 mesh screen. 
     The term, volatile flavorant, as used herein, pertains to a flavorant that volatilizes from the carbon at temperatures below the combustion temperature of the carbon, for example, at temperatures between about 50° C. and 300° C. 
     BACKGROUND OF THE INVENTION 
     Olin Corporation U.S. Pat. No. 3,744,496, discloses a carbon-filled paper to wrap cigarettes and/or cigars, preferably used as an inner liner with regular cigarette paper or cigar wrapper as an outer wrap. The paper described in U.S. Pat. No. 3,744,496 contains at least 5% carbon, thus making the appearance of the paper unacceptable for use as a white cigarette paper. 
     
         ______________________________________PARAMETERS OF THE INVENTION______________________________________Activated Carbon Content:              A small amount up to less              than 2%Preferred          0.1% to 1.0%Magnesium Hydroxide Content:              0.0% to 35%Preferred          0.0% to 20%Calcium Carbonate Content:              5.0% to 40%Preferred          10% to 30%Basis Weight:      20 gm/m.sup.2 to 100 gm/m.sup.2Preferred          25 gm/m.sup.2 to 65 gm/m.sup.2Porosity:          1 to 200 CorestaPreferred          5 to 125 CorestaFlavorants:Specific           Vanillin, ethyl vanillin,              3 methyl pentanoic acid,              ethyl valerate,              isoamyl isovalerateGeneral            Volatile, stable flavorants              used in cigarette and              cigar productionBurning Chemical:  Alkali metal salts of or-              ganic acids selected from              the group consisting of              citric, malic, lactic,              glycolic, tartaric, fumaric,              maleic, malonic, glutaric,              adipic, acetic, and succinicBurning Chemical   0.5% to 6.0%Addition rate:Acid Addition:     0.0% to 10% organic or              inorganic acid compatible              with the alkali metal              salt burning chemicalSugar Addition:    0.0% to 10% mono-, di-,              tri-, or polysaccharidesSmoking Articles:  Cigarettes, cigars, and              the like______________________________________ 
    
    
    
     DESCRIPTION OF THE INVENTION 
     It has been found that by putting low levels (less than 2%) of finely pulverized activated carbon having volatile flavorants absorbed thereon into regular, reduced sidestream smoke or heavy weight cigarette papers or coated onto the surface of the cigarette paper, an enhancement in mainstream smoke taste and/or sidestream smoke aroma can be effected. With proper selection of both the carbon type and particle size, type flavorants and level of flavorant treatment of the carbon, cigarette and cigar products can be produced which have totally acceptable appearance (light gray-white for cigarettes and tan to brown for cigars), while possessing enhanced mainstream smoke taste and sidestream smoke aroma. The truly novel findings resulting from this invention are (1) the discovery that when certain particle sizes (very fine) of carbon incorporated at certain levels (below 2%) into cigarette type papers, totally acceptable appearance of cigarettes and cigars can be produced, and (2) at these levels of carbon(less than 2%), sufficient levels of certain volatile flavorants can be absorbed onto the carbon to effect significant enhancements of both mainstream smoke taste and sidestream smoke aroma as the cigarette/cigar product is smoked. 
     This development can be utilized with acid treatments of the carbon or total paper, as per Owens U.S. patent application Ser. No. 514,533, filed Apr. 26, 1990; Owens U.S. patent application Ser. No. 756,542, filed Sep. 9, 1991; Owens U.S. patent application Ser. No. 756,543, filed Sep. 9, 1991; and Owens U.S. patent application Ser. No. 756,544, filed Sep. 9, 1991; and with addition of sugars to give improved ash characteristics. 
     PREFERRED EMBODIMENTS 
     Typical results demonstrating the effects obtained in accordance with this invention are described in the following examples, which are illustrative of the invention only and are not in limitation thereof. 
     EXAMPLE I 
     Carbon Treatment 
     Two grams of ethyl vanillin dissolved in 2 grams of 95% ethyl alcohol were added to 8 grams of GX 248 activated carbon from North American Carbon, Inc. The mixture was well mixed and allowed to stand overnight before being used to prepare handsheets. Handsheets were prepared of regular type cigarette paper having the following properties: Basis weight of 25 gm/m 2  containing 25% low surface area calcium carbonate and 1% of the ethyl vanillin treated carbon as prepared above. The handsheets were dried duplicating paper machine drying conditions and treated with a 2.0% solution of potassium citrate and redried again duplicating paper machine drying conditions. The resulting paper had a blue-white color and was cut into 27.5 mm×65 mm strips. Filtered king-size cigarettes (20 mm filter, 65 mm tobacco column) were prepared, using the handsheet cigarette paper, prepared as described above, as the cigarette wrapper. On smoking of the cigarette containing the ethyl vanillin treated carbon wrapper, a definite aroma of ethyl vanillin was observed in the sidestream smoke, and a pleasant vanillin taste was present in the mainstream smoke. Appearance of the cigarette was totally acceptable, having a normal grayish cast caused by the tobacco show-through of the paper. 
     EXAMPLE II 
     To 10 grams of GX 250 activated carbon from North American Carbon, Inc., was added 0.050 grams of 3 methyl pentanoic acid. The treated carbon was well mixed and allowed to stand overnight. Reduced sidestream smoke cigarette paper handsheets were then prepared having the following properties: Basis weight of 45 gm/M 2  containing 10% magnesium hydroxide prepared, as described in U.S. Pat. No. 4,915,118, 30% Ecusta low surface area calcium carbonate and 0.5% of the above-treated carbon. The handsheets were dried, as in Example I, and then treated with a 6.5% solution of potassium citrate and 1% sulfuric acid and redried. The potassium citrate and 1% sulfuric acid and redried. The resulting paper had a blue-white to very light gray color and was cut into 27.5 mm×65 mm strips. Filtered king-size cigarettes (20 mm filter, 65 mm tobacco column) were prepared, using the handsheet reduced sidestream smoke cigarette paper, as described above, as the cigarette wrapper. On smoking of the cigarette containing the 3 methyl pentanoic acid treated carbon wrapper, a definite enhancement of tobacco taste was noted in the mainstream taste, and an enhancement of the tobacco aroma was noted in the sidestream smoke. Appearance of the cigarette was totally acceptable. 
     
                                           TABLE 1__________________________________________________________________________FLAVORANT TREATED CARBON            %    %     Per.   Weight       Type Carbon                 Carbon                       Cig.                           Per                     CigaretteFlavorant   gm/M.sup.2       Carbon            in Paper                 Treatment                       (Mg)                           M.sup.2 ****                               Comments   Paper Color                                                   Appearance__________________________________________________________________________Ethyl Vanillin.sup.(a)   25  GX248.sup.1            1.0  25    0.11                           62.5                               Good EV taste/odor                                          Blue white                                                   AcceptableEthyl Vanillin   25  GX248            2.0  25    0.22                           125.0                               Strong EV taste/odor                                          Light Gray                                                   AcceptableEthyl Vanillin   25  GX248            0.5  25    0.06                           31.3                               Low/detectable EV                                          Light blue                                                   AcceptableEthyl Vanillin   45  GX248            1.0  25    0.20                           112.5                               Strong EV taste/odor                                          Very light                                                   AcceptableEthyl Vanillin   45  GX248            0.5  25    0.10                           56.3                               Good EV taste/odor                                          Blue white                                                   AccceptableEthyl Vanillin   45  GX248             0.25                 25    0.05                           28.1                               Low/detectable EV                                          Light blue                                                   AcceptableEthyl Vanillin   45  GX248            1.0  12.5  0.10                           56.3                               Good EV taste/odor                                          Very light                                                   AcceptableEthyl Vanillin   45  GX250.sup.2            1.8  12.5  0.10                           56.3                               Good EV taste/odor                                          Very light                                                   AcceptableEthyl Vanillin   45  GX250            2.0  12.5  0.20                           112.5                               Strong EV taste/odor                                          Light gray                                                   UnacceptableEthyl Vanillin   45  GX186.sup.3            1.0  12.5  0.10                           56.3                               Very low EV taste/                                          Black specks                                                   Unacceptable                               odorEthyl Vanillin   45  P100.sup.4            1.0  12.5  0.10                           56.3                               Good EV taste/odor                                          Very small                                                   Unacceptable                                          specksEthyl Vanillin   45  GX224.sup.5            1.0  12.5  0.10                           56.3                               Very low EV taste/                                          Small black                                                   Unacceptable                               odor       specks3 MPA*  45  GX250            1.0  2.5   0.02                           11.3                               Too strong, slightly                                          Very light                                                   Acceptable                               bitter3 MPA   45  GX250            0.5  0.50  0.002                            1.1                               Good enhanced                                          Very light                                                   Acceptable                               tobacco taste3 MPA   45  GX250            1.0  0.25  0.002                            1.1                               Good enhanced                                          Very light                                                   Acceptable                               tobacco taste3 MPA   45  GX250            1.0  0.15  0.0012                            0.7                               Low enhanced                                          Very light                                                   Acceptable                               tobacco taste3 MPA   45  GX250            1.0  0.05  0.0004                            0.2                               Minimal taste change                                          Very light                                                   Acceptable3 MPA   45  GX250            1.0  0.50  0.004                            2.3                               Strong enhanced                                          Very light                                                   Acceptable                               tobacco taste3 MPA   45  GX250            1.0  2.0   0.016                            9.0                               Too strong, slightly                                          Very light                                                   Acceptable                               bitter3 MPA   25  GX250            1.0  0.5   0.002                            1.3                               Good enhanced                                          Blue white                                                   Acceptable                               tobacco tasteChocolate**   45  GX250            1.0  10    0.08                           45.0                               Good chocolate taste/                                          Very light                                                   Acceptable                               aromaIA-IV***   45  GX250            1.0  10    0.08                           45.0                               Fruity aroma/taste                                          Very light                                                   Acceptable__________________________________________________________________________ .sup.(a) Applied to carbon from a 50% ethyl alcohol solution *3MPA = 3 Methyl pentanoic acid **Chocolate = Firmenich Chocolate Flavor 587.593 ***IA-IV = Isoamyl Isovalerate (Aldrich W208507) ****Cigarette Paper dimensions = 27.5 mm × 65 mm .sup.1 GX248 Woodbased activated carbon from:    North American Carbon, Inc.    432 McCormick Boulevard    Columbus, Ohio 432131585    Particle Size ASTM E11 = Greater than 98% thru 325 mesh    CCl.sub.4 activity  110% minimum .sup.2 GX250 Woodbased activated carbon from:    North American Carbon, Inc.    432 McCormick Boulevard    Columbus, Ohio 432131585    Particle size ASTM E11 = Greater than 99% thru 325 mesh    CCl.sub.4 activity  110% minimum .sup.3 GX186 Coconut shellbased activated carbon from:    North American Carbon, Inc.    432 McCormick Boulevard    Columbus, Ohio 432131585    Particle size ASTM E11 = 2.2% on 50 mesh    88.2% on 140 mesh    9.6% thru 140 mesh    CCl.sub.4 activity  60% minimum .sup.4 P100 Woodbased activated carbon from:    North American Carbon, Inc.    432 McCormick Boulevard    Columbus, Ohio 432131585    Particle size ASTM E11 = 8.4% on 200 mesh    26.5% on 325 mesh    73.5% thru 325 mesh    CCl.sub.4 activity  110% minimum .sup.5 GX224 Coconut shellbased activated carbon from:    North American Carbon, Inc.    432 McCormick Boulevard    Columbus, Ohio 432131585    Particle size ASTM E11 = 10.1% on 80 mesh    66.8% on 325 mesh    23.1% thru 325 mesh    CCl.sub.4 activity  60% minimum