Source: https://patents.google.com/patent/US5183062A/en
Timestamp: 2019-08-20 02:26:00
Document Index: 583395843

Matched Legal Cases: ['Application No. 342', 'Application No. 339', 'Application No. 336', 'Application No. 374', 'Application No. 342', 'Application No. 407', 'Application No. 342']

US5183062A - Cigarette - Google Patents
US5183062A
US5183062A US07/873,529 US87352992A US5183062A US 5183062 A US5183062 A US 5183062A US 87352992 A US87352992 A US 87352992A US 5183062 A US5183062 A US 5183062A
US07/873,529
1992-04-21 Application filed by R J Reynolds Tobacco Co filed Critical R J Reynolds Tobacco Co
1992-04-21 Priority to US07/873,529 priority patent/US5183062A/en
1993-02-02 Publication of US5183062A publication Critical patent/US5183062A/en
This is a continuation of copending application(s) Ser. No. 07/642,233 filed on Jan. 23, 1991, which is a continuation-in-part of U.S. patent application Ser. No. 488,516, filed Feb. 27, 1990, now U.S. Pat. No. 5,027,837.
Smoking articles which are capable of providing the pleasures associated with cigarette smoking, by heating but not necessarily burning tobacco, and without delivering considerable quantities of incomplete combustion products, are described in U.S. Pat. Nos. 4,714,082 to Banerjee et al; 4,756,318 to Clearman et al; 4,793,365 to Sensabaugh, Jr. et al; 4,819,665 to Roberts et al; 4,854,311 to Banerjee et al and 4,881,556 to Clearman et al; and European Patent Application No. 342,538. Such smoking articles employ a combustible fuel element for heat generation; and aerosol forming substances positioned physically separate from, and in a heat exchange relationship with, the fuel element. During use, heat generated by the fuel element acts to volatilize the aerosol forming substances, thereby providing a visible aerosol. Such smoking articles provide for extremely low yields of visible sidestream smoke as well as low yields of FTC "tar".
The smoking article, in one aspect, includes a short, preferably carbonaceous, combustible fuel element or heat source. Typically, the fuel element is of a longitudinally segmented design such that only a segment or portion of the length thereof is available for burning, and a segment or portion of the length thereof serves as a base which allows the fuel element to be secured in place within the smoking article. A preferred fuel element includes an isolation segment or portion positioned between the burning and base portions thereof. The preferred isolation segment has both a cross sectional periphery and cross sectional area which are smaller than that of the base segment. The preferred isolation segment has a cross sectional area, and in certain circumstances a cross sectional periphery, which are smaller than that of the burning segment.
A typical fuel element has a total length, prior to burning, of less than about 20 mm, and the length of the portion available for burning is less than about 15 mm. Preferred fuel elements are provided by subdividing a continuous extrudate into lengths, and employed such that extrusion axis of the fuel element is substantially perpendicular to the longitudinal axis of the smoking article into which the fuel element is incorporated.
In certain aspects of the present invention, the fuel element includes at least one void space extending therethrough in a direction transverse to the longitudinal axis of the smoking article into which the fuel element is incorporated. In other aspects of the present invention, the fuel element includes at least one airflow passageway (e.g., at least one void space) extending therethrough in a directional parallel to the longitudinal axis of the smoking article into which the fuel element is incorporated; and the airflow passageway can extend through the central region of the fuel element and/or as grooves along the periphery of the fuel element.
The smoking article includes a retaining means for maintaining the fuel element in position therewithin. The retaining means contacts the fuel element and secures the fuel element in position within the smoking article. In one preferred embodiment, a retaining member grasps the base of the fuel element, thereby serving to hold the fuel element securely in place. In another preferred embodiment, the retaining means is provided by a fibrous material (e.g., glass fibers or a tobacco filler/glass fiber mixture), gathered or shredded tobacco paper, gathered or shredded carbon paper or tobacco cut filler which contacts a significant length of the longitudinal periphery of the fuel element; and the longitudinally segmented nature of the fuel element in combination with the contact of the circumscribing material with the longitudinal periphery of the fuel element provides for the maintenance of that fuel element securely in place within the fibrous material, paper or tobacco cut filler.
The smoking article includes an aerosol generating means physically separate from, and longitudinally disposed from, the fuel element. The aerosol generating means includes a substrate and at least one aerosol forming material. A preferred aerosol generating means includes an aerosol forming material, such as tobacco of some form (e.g., densified tobacco pellets, tobacco extract or tobacco dust) and other aerosol forming materials (e.g., glycerin and/or tobacco flavoring agents, such as cocoa, licorice and sugars). The aerosol forming material generally is carried by a substrate, such as gathered paper, gathered tobacco paper, or a heat stable substrate (e.g., alumina beads). When the substrate is a paper-type material, it is highly preferred that such substrate be positioned in a spaced apart relationship with the fuel element.
The smoking article, in one aspect, includes an enclosure member, which preferably is a heat conducting member for transferring heat generated by the burning portion of the fuel element to the aerosol generating means. As such, the conducting member is in a heat exchange relationship, and preferably is in a conductive heat exchange relationship, with the substrate which carries the aerosol forming material. The enclosure member is radially spaced from the longitudinal periphery of the fuel element. Normally, the enclosure member contacts (i) a portion of the aerosol generating means, and (ii) a portion of the retaining member. Preferably, the enclosure member is radially spaced from the longitudinal outer periphery of the fuel element, at least a portion of the length of the burning portion of the fuel element, and contacts the aerosol generating means. As such, the fuel element and the enclosure member define an airflow passageway, and air drawn through the passageway is heated.
FIG. 9 is a cross sectional radial view of the cigarette shown in FIG. 8 taken along lines 9--9 in FIG. 8;
FIGS. 10 through 16 are longitudinal views of representative fuel elements for cigarettes of the present invention;
FIG. 17 is a longitudinal sectional view of a cigarette of the present invention;
FIG. 18 is a cross sectional radial view of the cigarette shown in FIG. 17 taken along lines 18--18 in FIG. 17;
FIGS. 19 and 20 are longitudinal sectional views of cigarettes of the present invention; and
FIG. 21 is a perspective of a representative fuel element for cigarettes of the present invention.
The heat source or fuel element 10, which preferably is an extruded carbonaceous material, has a generally square or rectangular cross sectional design. The preferred fuel element is a segmented fuel element which includes three longitudinally positioned portions or segments (as shown in FIG. 1); a burning portion 30 positioned near the extreme lighting end 31 of the cigarette, a base or supporting portion 32 at the opposite end (i.e., mouth end) of the fuel element, and an isolation portion 33 positioned between the burning and base portions. The fuel element 10 is configured so that (i) the cross sectional periphery of the base portion 32 is greater than the cross sectional periphery of the isolation portion, and (ii) the isolation portion includes at least one void space 35, which extends transversely through the fuel element. The void space acts to reduce the cross sectional area of the isolation portion, and as such, acts to minimize conduction of heat from the burning portion 30 to the base portion 33. In particular, void space 35 acts to assist in (i) providing separation of the burning and base segments, (ii) providing for a selected length over which the fuel element effectively burns, and (iii) minimizing conduction of heat from the burning portion of the fuel element through the base portion of the fuel element to other regions of the cigarette. The fuel element 10 includes optional ribbed grooves 37, 38 extending across the foremost face of the burning portion thereof. The grooves 37, 38 aid in increasing the ease with which the fuel element is lighted. The burning and base portions of the fuel element do not have any longitudinally extending air passageways extending entirely therethrough.
In use, the smoker lights the heat source or fuel element 10 (e.g., using a cigarette lighter) and the burning portion 30 of the fuel element burns to produce heat. The heat generated by the fuel element radiates outwardly to heat the portion of the cartridge 17 which encloses or surrounds the fuel element, and the heat is in turn conducted through the cartridge to the portion thereof which contacts the substrate 13 and aerosol forming material carried thereby. In addition, some heat is conducted through the base of the fuel element, and through the retaining member, to the substrate and aerosol forming material carried thereby. During draw by the smoker, drawn air passes through the airflow passage 57 between the fuel element and cartridge, and is heated upon contact with the hot fuel element and the heated cartridge. The heated drawn air then passes through the airflow passages 47, 48 between the retaining member 23 and the cartridge, and contacts the substrate 13 which is in a heat exchange relationship with the burning fuel element. The resulting heat applied to the aerosol forming material acts to volatilize that material. The volatilized material within the warm drawn air exits the cartridge through opening 52. The drawn air and volatilized material then cools during passage through the mouthend piece. Depending upon the particular aerosol forming material, a visible aerosol then is formed. In particular, the drawn air and volatilized material passes through the gathered tobacco paper 60, through the roll of tobacco cut filler 62, through the filter material 64, and into the mouth of the smoker. As the base portion does not burn during the use of the cigarette and the fuel element self-extinguishes after combustion of the burning portion is complete, the fuel element remains securely in the cigarette and does not have a tendency to become dislodged from the cigarette during use. Typically, the cigarette exhibits a tendency to self-extinguish when combustion of the burning portion of the fuel element is complete. When the fuel element self-extinguishes and no longer generates heat, the cigarette is disposed of.
The fuel element 10, which preferably includes longitudinally positioned portions or segments, is circumscribed by an air permeable insulating material 70, such as glass fibers. Representative air permeable insulating materials are described in U.S. patent application Ser. Nos. 576,751, filed Aug. 29, 1990 and 601,551 filed Oct. 23, 1990; European patent Application No. 339,690; at pages 48-52 of Chemical and Biological Studies of New Cigarette Prototypes That Heat Instead of Burn Tobacco, R. J. Reynolds Tobacco Co. publication (1988); and in U.S. Pat. No. 4,756,318 to Clearman et al; all of which are incorporated herein by reference. The insulating material preferably (i) is such that drawn air can pass therethrough, (ii) is positioned and configured so as to assist in holding the fuel element in place, and (ii) has a character such that heat generated by the burning fuel element is transferred to the portion of the cartridge which is radially spaced from the fuel element.
Referring again to FIG. 8, the fuel element 10 is inserted through the back of the enclosure member 17 such that the base portion 32 abuts inwardly extending lip or crimp 88. Then, the substrate 13 is positioned within cartridge 80, and the ends of that cartridge are crimped inwardly so as to enclose the substrate while maintaining inlet opening 90 and outlet opening 92 at each end of the cartridge. The cartridge then is inserted into the back of the enclosure member to abut the back of the base portion of the fuel element. Preferably, the inner dimensions of the enclosure member 17 and the outer dimensions of the cartridge 80 are such that the cartridge is secured firmly in place by a friction fit. As such, the front portion of the cartridge 80 and the crimp 88 in the enclosure member 17 provide a retaining means for holding the fuel element 10 securely in place within the cigarette.
FIGS. 10 through 16 illustrate representative configurations of heat sources or fuel elements which can be incorporated into smoking articles of the present invention, and particularly into those cigarettes previously described with reference to FIGS. 1 through 7.
Referring to FIG. 16, fuel element 10 is similar to the fuel element described with reference to FIG. 14.
Referring to FIG. 17, an alternate embodiment of the present invention has the form of a cigarette 8 which is similar in many respects to the cigarette illustrated in FIGS. 1, 2, 6 and 7. The cigarette includes a fuel element 10; a substrate 13 which carries aerosol forming material; a material 70 which surrounds the entire longitudinal periphery of the fuel element so as to hold the fuel element in place; and a tubular mouthend piece 28.
The fuel element 10 is longitudinally segmented, and includes a base portion 32, a burning portion 30 and an isolation portion 33 positioned between the burning and base portions. The fuel element 10 has a shape such that the circumference of the base portion 32 is greater than the circumference of the portion (e.g., the isolation portion 33) adjacent to the base portion. Preferably, the fuel element 10 includes at least one airflow passageway 98 extending as a slot or groove along the entire length of the fuel element.
The material 70 which surrounds the fuel element 10 can vary. The material 70 can be a material which has a tendency not to combust or a material which combusts easily to ensure ease of lighting of the smoking article. Most preferably, the material 70 is non-metallic in nature. Examples of suitable materials include glass fibers and other materials of the type in U.S. patent application Ser. No. 601,551, filed Oct. 23, 1990; European Patent Application No. 336,690; and pages 48-52 of Chemical and Biological Studies of New Cigarette Prototypes That Heat Instead of Burn Tobacco, R. J. Reynolds Tobacco Co. publication (1988). Examples of other suitable materials are glass fiber and tobacco mixtures such as are described in U.S. Pat. No. 4,756,318 to Clearman et al and U.S. patent application Ser. No. 576,751, filed Aug. 29, 1990. Examples of other suitable materials are gathered paper-type materials, shredded paper-type materials and paper-type materials which are spirally wrapped or otherwise wound around the fuel element. Suitable paper-type materials include treated papers; papers containing carbonaceous materials; tobacco-containing papers; wood pulp papers; sulfate papers; wood pulp/calcium carbonate containing papers; papers containing carbonaceous materials, wood pulp, tobacco and fillers such as those agglomerated materials described in U.S. patent application Ser. Nos. 414,833, filed Sep. 29, 1989 and 567,520, filed Aug. 15, 1990. The paper-type materials can be gathered or crimped and gathered around the fuel element; gathered into a rod using a rod making unit available as CU-10 or CU-20S from Decoufle s.a.r.b. or the apparatus described in U.S. Pat. No. 4,807,809 to Pryor et al.; wound around the fuel element about the longitudinal axis of the fuel element; or provided as longitudinally extending strands of paper-type sheet using the types of apparatus described in U.S. Pat. No. 4,889,143 to Pryor et al. and U.S. patent application Ser. No. 049,200, filed May 12, 1987, now U.S. Pat. No. 5,025,814 to Raker, which are incorporated herein by reference. Examples of paper-type sheet materials are available as P-2540-136-E carbon paper and P-2674-157 tobacco paper from Kimberly-Clark Corp.; and preferably the longitudinally extending strands of such materials (e.g., strands of about 1/32 inch width) extend along the longitude of the fuel element. The fuel element also can be circumscribed by tobacco cut filler (e.g., flue-cured tobacco cut filler treated with about 2 weight percent potassium carbonate). The number and positioning of the strands or the pattern of the gathered paper is sufficiently tight to maintain, retain or otherwise hold the fuel element within the cigarette.
The material 70 which surrounds the fuel element is circumscribed by a paper wrapper 101. Such a paper circumscribes the entire length of the material 70. An example of a suitable paper wrapper is available as P-850-63-5 from Kimberly-Clark Corp. A portion of the length of the paper wrapper 101 is in turn circumscribed by a second or outer paper wrapper 103. An example of a suitable outer paper wrapper is available as P-850-61-2 from Kimberly-Clark Corp.
The second paper wrapper 103 most preferably is a paper which exhibits a propensity not to burn (i.e., due to a very low porosity and/or due to chemical treatment), and preferably does not circumscribe paper wrapper 101 for a length of about 2 mm to about 8 mm, more preferably about 3 mm to about 6 mm, from the extreme lighting end of the cigarette. The second paper wrapper 103 also circumscribes at least a portion of the length of the tubular mouthend piece 28, and thereby act as a tipping material. The second wrapper acts to assist in preventing the fuel element from burning to any significant degree beyond the burning segment thereof. As such, the fuel element exhibits a tendency to self-extinguish prior to combustion, to any significant degree, of the isolation portion.
The substrate 13 is positioned behind the fuel element 10 within the tubular mouthend piece, and is positioned in a spaced apart relationship relative to the back end of the fuel element so as to have air space 104 therebetween. For example, the back end of the fuel element and the front end of the substrate are positioned about 1 mm to about 10 mm, preferably about 2 mm to about 5 mm apart. The substrate preferably includes a tube of gathered or layered paper 105, a short segment of gathered paper 106 positioned within the tube 105 at the end of the tube near the back end of the fuel element, and an air space 107 behind the gathered paper 106. The gathered paper provides a plurality of longitudinally extending airflow passageways. The gathered paper web normally is circumscribed by a paper wrapper 55. The inner surface of the tubular mouthend piece preferably is coated, particularly in the region thereof adjacent the substrate, with a material which tends to limit the amount of aerosol forming material which migrates from the substrate 13. Examples of suitable materials are ethyl cellulose (e.g., which is applied as a dilute solution in ethanol), or a material which is available as Hercon 70 from Hercules, Inc. The region of the mouthend piece adjacent the fuel element and/or the region of paper wrappers 101, 103 which are positioned outward from the base segment of the fuel element can be coated with aqueous solutions of calcium chloride or diammonium hydrogen orthophosphate, and allowed to dry.
Referring to FIG. 18, the fuel element 10 includes grooves 98, 108 extending along the outer longitudinal periphery thereof. Other configurations of grooves or airflow passageways through the fuel element can be employed.
Referring to FIG. 19, an alternate embodiment of the present invention has the form of cigarette 8 which is similar in many respects to the cigarette illustrated in FIG. 17. The cigarette includes a fuel element having a void space 35 extending entirely therethrough in a direction transverse to the longitudinal axis of the cigarette, and extending along a significant length of the fuel element. A portion of the length of the base portion 32 of the fuel element 10 extends beyond circumscribing material 70, and as such provides for an airflow passageway through the fuel element, particularly after the fuel element has been lit. Material 70 circumscribes the burning and isolation portions of the fuel element. However, if desired, a portion of the length of the burning portion can extend beyond the circumscribing material 70. The back end of the fuel element is positioned in a spaced apart relationship relative to the substrate 15. The substrate optionally can have certain fairly large longitudinally extending airflow passageways or grooves 110, 112.
Referring to FIG. 20, an alternate embodiment of the present invention has the form of cigarette 8 which is similar in many respects to the cigarette illustrated in FIG. 17. The base portion 32 of the fuel element 10 has a significantly greater circumference than that of both of the burning and isolation portions 30, 33; and includes an airflow passageway (not shown) extending as a groove along the entire length of the fuel element. The substrate 13 is provided in an essentially cup shape within the tubular mouthend piece 28 by inserting a circular piece of paper having a diameter of about 2.5 to about 4 times that of the inner diameter of the mouthend piece through the extreme mouthend of the mouthend piece, and crimping or otherwise forming that paper to the desired shape within the mouthend piece.
Referring to FIG. 21 fuel element 10 includes void space 35 extending transversely through the isolation portion 33, and airflow passageways 98, 108, 116, 117 extending as grooves along the longitudinal periphery of the fuel element. Such a fuel element can be made by machining an extruded fuel element or by compression molding techniques. Such a fuel element is particularly suited for use in the types of cigarettes described with reference to FIGS. 17 and 19.
Smoking articles of the present invention incorporate some form of tobacco. The form of the tobacco can vary, and more than one form of tobacco can be incorporated into a particular smoking article. The tobacco can be incorporated in the fuel element, the aerosol generating means, and/or positioned within the mouthend piece in a manner so that various flavorful tobacco components are transferred to drawn aerosol passing through the mouthend piece. The type of tobacco can vary, and includes flue-cured, Burley, Md. and Oriental tobaccos, the rare and specialty tobaccos, as well as blends thereof.
One form of tobacco is tobacco cut filler (e.g., strands or shreds of tobacco filler having widths of about 1/15 inch to about 1/40 inch, and lengths of about 1/4 inch to about 3 inches). Tobacco cut filler can be provided in the form of tobacco laminae, volume expanded or puffed tobacco laminae, processed tobacco stems including cut-rolled or cut-puffed stems, or reconstituted tobacco material. Processed tobaccos, such as those described in U.S. patent application Ser. Nos. 392,519, filed Aug. 10, 1989, now U.S. Pat. No. 5,025,812, to Fagg et al., and 484,587, filed Feb. 23, 1990, also can be employed. Reconstituted tobacco material can be provided using cast sheet techniques; papermaking techniques, such as described in U.S. Pat. Nos. 4,962,774 to Thomasson et al and 4,987,906 to Young et al; or extrusion techniques, such as are described in U.S. Pat. No. 4,821,749 to Toft et al. Cut filler normally is incorporated into the cigarette as a cylindrical roll or charge of tobacco material which is wrapped in a circumscribing paper wrapper. Tobacco cut filler can be provided as a roll in a paper wrapper using cigarette rod making techniques and apparatus which are well known by the skilled artisan. Tobacco cut filler also can be incorporated in the aerosol generating means, if desired. Another form of tobacco is tobacco paper. For example, a web of tobacco paper available as P144-GNA from Kimberly-Clark Corp. can be gathered into a cylindrical segment in a manner set forth in Example 2 of U.S. Pat. No. 4,807,809 to Pryor et al. Cylindrical segments of gathered tobacco paper can be incorporated (i) into the aerosol generating means to act as a substrate for the aerosol forming material, and/or (ii) within the mouthend piece of the cigarette. If desired, tobacco paper can form an inner liner of the tubular mouthend piece of the smoking article.
Another form of tobacco is a tobacco extract. Tobacco extracts typically are provided by extracting a tobacco material using a solvent such as water, carbon dioxide, sulfur hexafluoride, a hydrocarbon such as hexane or ethanol, a halocarbon such as a commercially available Freon, as well as other organic and inorganic solvents. Tobacco extracts can include spray dried tobacco extracts, freeze dried tobacco extracts, tobacco aroma oils and tobacco essences. Methods for providing suitable tobacco extracts are set forth in U.S. Pat. Nos. 4,506,682 to Mueller and 4,986,286 to Roberts et al; European Patent Application Nos. 326,370 and 338,831; and U.S. patent application Ser. No. 452,175 filed Dec. 18, 1989. Also useful are flavorful tobacco compositions such as those described in European Patent Application No. 374,779. Yet another tobacco extract is provided by extracting 1 weight part tobacco cut filler with about 6 weight parts water in a stainless steel column at ambient temperature to provide an aqueous tobacco extract having a solids content of about 15 weight percent; freezing the aqueous extract to a frozen block; melting about one half of the weight of the frozen block; collecting the resulting melted water and extract; freezing the extract and water so collected to a frozen block; melting about one half of the weight of the frozen block; and collecting the resulting melted water and extract. Typically, at least one tobacco extract is carried by the substrate of the aerosol generating means; although the tobacco cut filler, tobacco paper and filter material are positioned elsewhere within the cigarette. Furthermore, tobacco extract can be incorporated into the fuel element.
A smoking article of the present invention includes an aerosol generating means which is physically separate from the fuel element. As such, the aerosol generating means is not mixed with, or is not part of, the fuel element. The aerosol generating means is in a heat exchange relationship with the fuel element in order that heat generated by the burning fuel element is transferred to the aerosol generating means for heating and volatilizing the aerosol forming material, particularly during periods of draw by the smoker.
One type of substrate has the form of a non-woven sheet-like material or a cellulosic material, such as paper, carbon paper or tobacco paper. Such a substrate typically is provided as a cylindrical segment including a shredded, gathered, pleated or crimped web of paper-type material within a circumscribing outer wrapper. The circumscribing outer wrapper preferably is a paper material, and can be a paper material treated so as to limit the migration of aerosol forming material to other parts of the smoking article. If desired, the circumscribing outer wrapper can be a metallic (e.g., aluminum) foil. Such cylindrical segments can be provided from rods which are manufactured using equipment and techniques described in U.S. Pat. No. 4,807,809 to Pryor et al. Exemplary papers which are gathered to form substrates are available as MS2408/S538 from Filtrona, Ltd. as well as P-1976-29-5, P-1976-29-7, P-1976-29-1, P-1976-29-8 and P-1976-29-11 from Kimberly-Clark Corp. Combinations of two or more papers or paper-type materials can be employed. Exemplary tobacco papers which are gathered to form substrates are available as P144-GNA from Kimberly-Clark Corp., and also include the carbon filled tobacco sheet materials described in European Patent Application No. 342,538, which is incorporated herein by reference. Another substrate can have the form or a porous, air permeable pad which wicks liquid aerosol forming material from a container. The sheet-like material used as the substrate can have fillers having certain pore structures physically mixed therewith and/or incorporated therein in order to control migration of aerosol forming material from the substrate. However, substrates manufactured from non-metallic materials, and absent of metallic materials are often preferred.
The aerosol generating means includes aerosol forming material, and the aerosol forming material is in a heat exchange relationship with the fuel element. The aerosol forming material can have a liquid, semi-solid or solid form, and generally is carried by a substrate. Examples of preferred aerosol forming materials include the polyhydric alcohols (e.g., glycerin, propylene glycol, triethylene glycol and tetraethylene glycol), the aliphatic esters of mono-, di-, or poly-carboxylic acids (e.g., methyl stearate, dimethyl dodecandioate and dimethyl tetra decanedioate), Hystar TPF available from Lonza, Inc., and the like, as well as mixtures thereof. For example, glycerin, triethylene glycol and Hystar TPF can be mixed together to form an aerosol forming material. Examples of other aerosol forming materials include volatile flavoring agents and tobacco flavor modifiers. Volatile flavoring agents include menthol, vanillin, cocoa, licorice, organic acids, high fructose corn syrup, and the like. Various other flavoring agents for smoking articles are set forth in Leffingwell et al, Tobacco Flavoring For Smoking Products (1972) and in European Patent Application No. 407,792. Tobacco flavor modifiers include levulinic acid, metal (e.g., sodium, potassium, calcium and magnesium) salts of levulinic acid, and the like.
The amount of aerosol forming material which is employed per smoking article can vary and depends upon factors such as the components of the aerosol forming material and the composition of the particular substrate which carries the aerosol forming material. Generally, the amount of aerosol forming material employed per smoking article ranges from about 20 mg to about 200 mg, preferably about 35 mg to about 150 mg. When paper or paper-type substrates are employed, it is preferable that the weight of the aerosol forming material which is carried by that substrate be about 2 to about 4 times the dry weight of the substrate material.
A highly preferred fuel element has a segmented design. Such a fuel element is designed in order that during use of the smoking article into which the fuel element is incorporated (i) a portion of the length of the fuel element is available for burning, and (ii) a remaining longitudinal portion of the fuel element does not burn. The portion of the fuel element which is designed not to burn can be provided with such a characteristic as a result of factors such as (i) the selection of the composition of that portion of the fuel element, (ii) the overall shape or configuration of the fuel element, (iii) the location of the fuel element within the smoking article, and (iv) the manner in which the fuel element is secured within the smoking article. The preferred segmented fuel element includes (i) a burning portion for heat generation, (ii) a non-burning portion including a base or support portion, and (iii) an isolation portion positioned between the burning and base portions. A preferred segmented fuel element also is designed and configured so that heat does not transfer readily from the burning portion of the fuel element to the non-burning portion of the fuel element. As such, conductive transfer of heat from the fuel element to other regions of the smoking article is controlled, and preferably is minimized, in order that the burning fuel element does not exhibit a propensity to self-extinguish over normal smolder periods. Normally, the length of the burning portion of the fuel element is about 2 mm to about 15 mm, preferably about 4 mm to about 8 mm, prior to burning. Normally, the length of the base portion of the fuel element is about 1 mm to about 3 mm. Normally, the length of the isolation portion of the fuel element is up to about 10 mm, preferably up to about 5 mm.
The composition of the combustible material of the fuel element can vary. Preferred fuel elements contain carbon, and highly preferred fuel elements are composed of carbonaceous materials. Preferred carbonaceous materials have a carbon content above about 60 weight percent, more preferably above about 75 weight percent. Flavors, tobacco extracts, fillers (e.g. clays or calcium carbonate), burn additives (e.g., sodium chloride to improve smoldering and act as a glow retardant), combustion modifying agents (e.g., potassium carbonate to control flammability), binders, and the like, can be incorporated into the fuel element. Exemplary compositions of preferred carbonaceous fuel elements are set forth in U.S. Pat. Nos. 4,714,082 to Banerjee et al, 4,756,318 to Clearman et al and 4,881,556 to Clearman et al; as well as in European Patent Application Nos. 236,992 and 407,792; which are incorporated herein by reference. Other fuel elements can be provided from comminuted tobacco material, reconstituted tobacco material, heat treated or pyrolyzed tobacco materials, cellulosic materials, modified cellulosic materials, and the like. Exemplary materials are set forth in U.S. Pat. Nos. 4,347,855 to Lanzilotti et al; 3,931,824 to Miano et al; 3,885,574 to Borthwick et al and 4,008,723 to Borthwick et al; as well as in Sittig, Tobacco Substitutes, Noyes Data Corp. (1976). Exemplary carbonaceous materials are coconut hull carbons, such as the PXC carbons available as PCB and the experimental carbons available as Lot B-11030-CAC-5, Lot B-11250-CAC-115 and Lot 089-A12-CAC-45 from Calgon Carbon Corp.
Fuel elements for smoking articles of the present invention advantageously are molded, machined, pressure formed or extruded into the desired shape. Molded fuel elements can have passageways, slots, grooves or hollow regions therein. Preferred extruded carbonaceous fuel elements can be prepared by admixing up to 95 parts carbonaceous material, up to 20 parts binding agent and up to 20 parts tobacco (e.g., tobacco dust and/or a tobacco extract) with sufficient water to provide a paste having a stiff dough-like consistency. The paste then can be extruded using a ram, screw or piston type extruder into an extrudate of the desired shape having the desired number of passageways or void spaces. The extrudate can be passed through a pair of spiked or grooved rollers in order to imprint grooves (either transversely or longitudinally to the extrusion axis of the extrudate) at regular intervals, so as to provide a particular surface character to selected surfaces of the ultimate fuel element. The extrudate then can be dried to a low moisture content, typically between about 2 and about 7 weight percent. Then, a continuous length of extrudate is cut or otherwise subdivided at regular intervals, to provide a plurality of individual fuel elements. As such, it is possible to provide a fuel element having an extrusion axis which is perpendicular (i.e., rather than parallel) to the longitudinal axis of the smoking article into which the fuel element is ultimately incorporated. If desired, various types of materials can be co-extruded to provide fuel elements having burning portions and base portions which are of different compositions. For example, (i) the base and isolation portions of the fuel element can be composed of a material having a combustion propensity less than that material which is used to provide the burning portion of the fuel element, or (ii) the extreme lighting end of the fuel element can be composed of a material having an extremely high combustion propensity so as to increase the ease with which the fuel element is lighted.
A segment of gathered tobacco paper can be incorporated into the mouthend piece. Such a segment can be positioned directly behind the heat conducting member which contains the aerosol forming material. A segment of gathered carbon paper can be incorporated into the mouthend piece, particularly in order to introduce menthol flavor to the aerosol. Suitable gathered carbon paper segments are described in European Patent Application No. 342,538. If desired, a segment including a gathered web of non-woven polypropylene or polyester in intimate contact with a water soluble tobacco extract can be incorporated into the mouthend piece. Such a segment is described in U.S. patent application Ser. Nos. 414,835, filed Sep. 29, 1989 and 621,499, filed Dec. 7, 1990.
Smoking articles of the present invention are capable of providing at least about 6 to about 10 puffs, when smoked under FTC smoking conditions. FTC smoking conditions consist of a 35 ml puff volume of 2 seconds duration, separated by 58 seconds of smolder. A typical fuel element of a preferred smoking article of the present invention provides less than about 300 calories, preferably between about 200 and about 250 calories, when the article is smoked under FTC smoking conditions. During the period that the preferred smoking article is smoked, at least about 40 percent, preferably at least about 65 percent, more preferably at least about 75 percent of the heat produced by the burning fuel element is used for heating the aerosol generating means and for the consequential generation of aerosol for mainstream aerosol delivery.
Preferred combustible fuel elements generate temperatures of about 400° C. to about 850°C., more preferably about 400° C. to about 700° C. Due to the relatively low temperatures and relatively low amounts of heat generated by the preferred fuel elements, typical smoking articles incorporating such fuel elements yield less than about 10 mg, preferably less than about 5 mg, and most preferably less than about 2 mg of carbon monoxide, when smoked under FTC smoking conditions.
Into the cartridge is inserted the retaining member such that the fuel element held in place by the retaining member extends about 1 mm beyond the front of the cartridge. The retaining member is held firmly in place within the cartridge by a friction fit.
Into one end of the paper tube is inserted the cartridge such that the front fact of the fuel element is flush with the front end of the paper tube. As a result, the extrusion axis of the fuel element is perpendicular to the longitudinal axis of the cigarette. The cartridge is held in place securely within the paper tube by friction fit.
The cigarette is smoked under FTC smoking conditions. The cigarette yields about 0.7 mg glycerin over the first 3 puffs, and about 0.8 mg glycerin over the second 3 puffs. The cigarette yields visible aerosol and tobacco flavor on all puffs for about 13 puffs. The cigarette exhibits a pressure drop of about 65 mm H2 O at 7.5 cc/sec air flow rate as measured using a Filtrona Filter Test Station (CTS Series) available from Filtrona Instruments and Automation Ltd.
Cigarettes of the type illustrated in FIG. 17 are manufactured in the following manner:
A segmented fuel element has base, isolation and burning portions; and an overall length of about 14 mm. The longitudinal length of the base portion is about 3 mm, the longitudinal length of the isolation portion is about 8 mm, and the longitudinal length of the burning portion is about 3 mm. The cross sectional shape of the base portion is circular, and the base portion is about 4.5 mm in diameter. The isolation portion is generally rectangular in cross sectional shape and the isolation portion is about 4.5 mm wide and about 2 mm thick. The cross sectional shape of the burning portion is circular, and the burning portion is about 4.5 mm in diameter. The fuel element includes 2 grooves formed along the entire length of the fuel element, positioned on each side of the fuel element about 180° apart. Each groove is about 0.75 mm wide and about 1.5 mm deep. The fuel element weighs about 163 mg, and has a density of about 1.8 g/cc as determined using a helium pycnometer.
The fuel element is provided by extruding a paste of tobacco dust, hardwood pulp carbon and sodium carboxymethylcellulose binder available as Hercules 7HXFCMC from Hercules Inc.
The hardwood pulp carbon is provided generally as described in Example 1, and is ground to a fine powder having an average particle size of about 10 to about 14 microns in diameter.
About 72 parts of the finely powdered hardwood carbon is admixed with about 20 parts fine tobacco dust and about 8 parts of the sodium carboxymethylcellulose binder, and sufficient water to provide a mixture having a stiff, dough-like paste form. The tobacco dust is provided by ball milling an "American Blend" of tobacco cut filler to a particle size of about 12 microns in diameter.
Fuel elements are extruded from the paste using a ram extruder. The extrusion axis of the extrudate is such that the extrusion axis of the resulting fuel element is parallel to the longitudinal axis of the cigarette into which the fuel element is incorporated. The extrudate is extruded so that 2 grooves extend along its length. The resulting extrudate is air dried. The dried extrudate then is cut into sections of 14 mm lengths, thereby providing a plurality of fuel elements. The fuel elements are machined using a diamond cutting wheel to provide the isolation segment.
The fuel element is circumscribed by glass fibers of the type described in pages 48-52 of Chemical and Biological Studies of New Cigarette Prototypes That Heat Instead of Burn Tobacco, R. J. Reynolds Tobacco Co. publication (1988). The glass fibers are in turn circumscribed by a paper wrapper available as P-850-63-5 from Kimberly-Clark Corp. so as to provide a cylinder having open ends for the passage of air therethrough, a length of about 14 mm and a circumference of about 7.5 mm.
A rod of gathered filter paper available as MS2408/S538 from Filtrona, Ltd. is cut to a segment having a length of about 5 mm, and a length of about 3 mm and a diameter of about 3 mm is punched therefrom through the center of the segment. The segment has a dry weight of about 55 mg, and about 125 mg glycerin is added to the substrate.
A tube of about 63 mm length and about 7.5 mm diameter is made from a web of paper about 27 mm wide. The paper is a 76 lb. Mouthpiece Paper having a thickness of about 0.012 inch, and is available from Simpson Paper Co. The paper is formed into a tube by lap-joining the paper using a water-based ethylene vinyl acetate adhesive. The inner surface of the tube is coated with Hercon 70 from Hercules, Inc. about 10 mm into the tube and allowed to dry. Then, the coated inner surface of the tube is coated with an aqueous solution of calcium chloride, and allowed to dry.
Into the coated end of the paper tube is inserted the substrate such that the front face of the substrate is about 3 mm from the front end of the paper tube. The substrate is held in place securely within the paper tube by friction fit.
Into the opposite end of the tube is inserted a 10 mm length segment of tobacco cut filler wrapped in a circumscribing paper wrapper. The segment is inserted into the tube so that the back end of the segment is about 10 mm from the extreme mouth end of the tube.
The mouthend piece and front end are positioned in an abutting, end-to-end relationship, such that the front face of the substrate is positioned about 3 mm from the back face of the fuel element. The front end and mouthend pieces are held together by a circumscribing paper wrapper which acts as a tipping paper. The paper wrapper is a low porosity paper and available as P-850-61-2 from Kimberly-Clark Corp., and circumscribes the entire length of the front end piece except for about a 3 mm length of the front end piece at the extreme lighting end thereof.
The cigarette contains no metallic heat conducting cartridge, no metallic retaining means and no metallic substrate components. The fuel element is held firmly in place within the cigarette by the insulating glass fibers which surround the fuel element.
Cigarettes are manufactured as described in Example 4, except that the following configuration and substrate materials are employed:
The substrate has essentially the same dimensions as described in Example 4, except that the portion having the length of about 5 mm is provided as a tube of wound paper available as P-1981-152 from Kimberly-Clark Corp.; and the inner segment having a length of about 2 mm and a diameter of about 3 mm is provided by gathering a paper available as P-780-63-5 from Kimberly-Clark Corp.
The front-end piece is provided by circumscribing the fuel element and glass fibers with the paper available as P-850-63-5 from Kimberly-Clark Corp., and then circumscribing that with the paper available as P-850-61-2 from Kimberly-Clark Corp. except for about a 3 mm length of the front-end piece at the extreme lighting end thereof.
A tube of the mouthpiece paper from Simpson Paper Co., having a length of about 74 mm, is inserted over the front-end piece so as to expose the foremost 3 mm of the front-end piece, and is held in place by friction fit. The inner surface of the tube is coated using materials and techniques in Example 4. The substrate is positioned within the tube so that the back face of the fuel element and the front face of the substrate are about 3 mm apart.
The remaining components of the cigarette are provided, essentially as described in Example 4.
(a) a combustible fuel element having a portion which burns during use and a portion which does not burn during use;
(b) aerosol generating means (i) physically separate from, longitudinally adjacent, and in a heat exchange relationship with, the fuel element, and (ii) including a paper substrate;
(c) a mouthend piece; and
2. The cigarette of claim 1, wherein the portion of the fuel element which burns during use comprises a burning segment of the fuel, the portion which does not burn during use comprises a base segment of the fuel, and the burning segment is physically different from the base segment.
12. A cigarette having a longitudinal axis and comprising
(a) an extruded fuel element having an extrusion axis, the fuel element being a longitudinally segmented combustible fuel element having a burning segment and a base segment, and the fuel element being positioned within the cigarette such that the extrusion axis of the fuel element is substantially perpendicular to the longitudinal axis of the cigarette;
(b) aerosol generating means (i) physically separate from, longitudinally disposed from, and in a heat exchange relationship with, the fuel element, and (ii) including a paper substrate carrying at least one aerosol forming material;
(c) retaining means circumscribing and contacting the longitudinal periphery of the fuel element to secure the fuel element in position within the cigarette;
(d) a mouthend piece; and
(e) tobacco.
13. The cigarette of claim 12, wherein the fuel element further includes an isolation segment positioned between the burning and base segments, and the burning and base segments are physically different from the isolation segment.
(a) a longitudinally segmented combustible fuel element having a burning segment and a base segment;
(b) aerosol generating means (i) physically separate from, longitudinally disposed from, and in a heat exchange relationship with, the fuel element, and (ii) including a paper substrate; and
(c) retaining means circumscribing the fuel element and securing the fuel element in position within the smoking article.
18. The smoking article of claim 17, wherein the fuel element further includes an isolation segment positioned between the burning and base segments, and the burning base segments are physically different from the isolation segment.
23. A smoking article having a longitudinal axis and comprising
(b) aerosol generating means (i) physically separate from, longitudinally disposed from, and in a heat exchange relationship with, the fuel element, and (ii) including a paper substrate carrying at least one aerosol forming material; and
(c) retaining means for securing the fuel element in position within the smoking article.
24. The smoking article of claim 23, wherein the fuel element further includes an isolation segment positioned between the burning and base segments, and the burning and base segments are physically different from the isolation segment.
(a) a longitudinally segmented combustible fuel element;
(b) aerosol generating means (i) physically separate from, longitudinally disposed from, and in a heat exchange relationship with, the fuel element, and (ii) including a substrate comprising a gathered web;
34. A smoking article comprising:
(b) aerosol generating means (i) physically separate from, longitudinally disposed from, and in a heat exchange relationship with, the fuel element, and (ii) including a substrate comprising a gathered web; and
35. A cigarette comprising
a) a combustible fuel element less than 20 mm in length prior to smoking;
b) an aerosol generating means including a paper substrate carrying an aerosol forming material which is longitudinally spaced about 1 to 10 mm from the fuel element; and
c) a non-metallic retaining member circumscribing the fuel element and contacting the entire longitudinal periphery of the fuel element, for retaining the fuel element within the cigarette.
36. The cigarette of claim 35, further including a non-burning wrapper circumscribing the retaining material which is spaced at least about 2 mm from the lighting end of the fuel element.
40. The cigarette of claim 35, wherein the material circumscribing the fuel element comprises a gathered or shredded paper material.
41. The cigarette of claim 38 or 40, wherein the material circumscribing the fuel element is non-burning.
42. The cigarette of claim 41, wherein the non-burnable material is a metal foil or paper treated with a burn retardant.
43. The cigarette of claim 40, wherein the paper material circumscribing the fuel element contains carbon.
44. The cigarette of claim 40, wherein the paper material circumscribing the fuel element is a tobacco-containing paper.
45. The cigarette of claim 38, wherein the migration resistant material comprises calcium chloride, ethyl cellulose, diammonium orthophosphate, or Hercon 70.
46. A cigarette comprising
c) material circumscribing the fuel element for retaining the fuel element within the cigarette;
the material circumscribing the fuel element consisting essentially of insulating material.
47. The cigarette of claim 46, wherein the paper substrate is spaced about 2 to 5 mm from the fuel element.
48. The cigarette of claim 35 or 46, wherein the paper substrate is a gathered web.
49. The cigarette of claim 48, wherein the weight of the aerosol forming material carried by the substrate is about 2 to 4 times the dry weight of the paper substrate.
50. The cigarette of claim 49, wherein the paper substrate is circumscribed by a material which limits the migration of the aerosol forming material from the substrate.
51. The cigarette of claim 35 or 46 wherein the paper substrate comprises a tobacco containing material.
52. The cigarette of claim 46, wherein the fuel element provides less than about 250 calories under FTC smoking conditions.
(b) physically separate aerosol generating means comprising a paper substrate and an aerosol forming material;
(c) a mouthend piece, and
(d) a non-metallic retaining member circumscribing the fuel element and contacting the entire longitudinal periphery of the fuel element, for retaining the fuel element within the cigarette; and
(e) a non-burnable material which circumscribes at least a portion of the longitudinal periphery of the fuel element, the non-burnable material being longitudinally spaced about 2 mm to about 8 mm from the lighting end of the fuel element.
54. The cigarette of claim 53, further comprising an ignitable material which circumscribes at least a portion of the longitudinal periphery of the fuel element.
55. The cigarette of claim 53, wherein the non-burnable material is spaced about 3 mm to about 6 mm from the lighting end of the fuel element.
56. A cigarette comprising:
(b) a non-metallic retaining member circumscribing the fuel element and contacting the entire longitudinal periphery of the fuel element, for retaining the fuel element within the cigarette;
(c) physically separate aerosol generating means comprising a substrate and an aerosol forming material, at least a portion of the periphery of the substrate being circumscribed by a material which resists migration of aerosol forming material prior to smoking; and
57. The cigarette of claim 56, wherein the migration resistant material comprises calcium chloride, ethyl cellulose, diammonium hydrogen orthophosphate, or Hercon 70.
58. The cigarette of claim 1, wherein the paper substrate comprises gathered paper wrapped in a circumscribing paper wrapper.
59. A cigarette comprising:
(c) at least a portion of the fuel element and at least a portion of the aerosol generating means being circumscribed by a paper which exhibits the propensity not to burn during use of the cigarette,
60. The cigarette of claim 59, wherein the non-burning paper has a porosity which is too low to support combustion.
61. The cigarette of claim 59, wherein the non-burning paper is chemically treated to prevent combustion.
62. The cigarette of claim 59, wherein the paper substrate is circumscribed with a non-metallic material which resists migration.
63. The cigarette of claim 62, wherein the migration resisting material comprises ethyl cellulose or Hercon 70.
64. The cigarette of claim 59, wherein the paper substrate is circumscribed by a paper coated with calcium chloride.
65. A cigarette comprising:
(a) a combustible fuel element less than 20 mm in length prior to smoking;
(b) an aerosol generating means including a paper substrate carrying an aerosol forming material which is longitudinally spaced about 1 to 10 mm from the fuel element; and
(c) a non-metallic retaining member circumscribing the fuel element and contacting the entire longitudinal periphery of the fuel element, for retaining the fuel element within the cigarette.
66. The cigarette of claim 65, wherein the material circumscribing the fuel element consists essentially of insulating material.
67. The cigarette of claim 65, wherein the paper substrate is a gathered web.
68. The cigarette of claim 65, wherein the weight of the aerosol forming material carried by the substrate is about 2 to 4 times the dry weight of the substrate.
69. The cigarette of claim 65, wherein the substrate is circumscribed by a material which limits the migration of the aerosol forming material from the substrate.
70. The cigarette of claim 69, wherein the material which resists migration comprises paper bearing a migration-resistant coating.
71. The cigarette of claim 65, further including a non-burning wrapper circumscribing the non-metallic retaining member, the non-burning wrapper being spaced at least about 2 mm from the lighting end of the fuel element.
72. The cigarette of claim 65, 67 or 69 wherein the paper substrate comprises carbon or tobacco.
73. The cigarette of claim 65, wherein the non-metallic retaining member is a fibrous material comprising glass fibers, tobacco cut filler, tobacco paper, carbon paper or a tobacco filler/glass fiber mixture.
74. The cigarette of claim 65, wherein the material circumscribing the fuel element comprises a gathered or shredded paper material.
75. The cigarette of claim 74, wherein the paper material circumscribing the fuel element contains carbon, tobacco or mixtures thereof.
76. The cigarette of claim 65, wherein the material circumscribing the fuel element is non-burning.
77. A cigarette comprising:
(b) a physically separate aerosol generating means comprising a substrate and an aerosol forming material;
78. The cigarette of claim 71 or 77, wherein the non-burnable material is a metal foil or paper treated with a burn retardant.
79. The cigarette of claim 77, further comprising an ignitable material which circumscribes at least a portion of the longitudinal periphery of the fuel element.
80. A cigarette comprising:
(b) a non-metallic retaining member circumscribing the fuel element and contacting substantially the entire longitudinal periphery for retaining the fuel element within the cigarette;
US07/873,529 1990-02-27 1992-04-21 Cigarette Expired - Fee Related US5183062A (en)
US07/873,529 US5183062A (en) 1990-02-27 1992-04-21 Cigarette
US64223391A Continuation 1991-01-23 1991-01-23
US5183062A true US5183062A (en) 1993-02-02
ID=27413809
US07/873,529 Expired - Fee Related US5183062A (en) 1990-02-27 1992-04-21 Cigarette
US (1) US5183062A (en)
CN100496308C (en) 2006-06-02 2009-06-10 上海烟草（集团）公司 Semi-countercurrent multi-stage extracting process for reproducing tobacco leaves by paper-making method
US20120138074A1 (en) * 2010-12-01 2012-06-07 Rj Reynolds Tobacco Company Smokeless tobacco pastille and moulding process for forming smokeless tobacco products
US20140123986A1 (en) * 2003-11-07 2014-05-08 U.S. Smokeless Tobacco Company Tobacco Compositions
WO2017211600A1 (en) * 2016-06-08 2017-12-14 Philip Morris Products S.A. Electrically operated aerosol-generating system with multiple-component aerosol-generating article
WO2019061606A1 (en) * 2017-09-26 2019-04-04 南通金源新材料有限公司 Heat-not-burn cigarette having cavity container section
1992-04-21 US US07/873,529 patent/US5183062A/en not_active Expired - Fee Related
EP0352106A2 (en) 1990-01-24 Smoking article