EP0250806A2 - Procédé et dispositif pour éliminer l'oxyde nitrique de la fumée de cigarette - Google Patents

Procédé et dispositif pour éliminer l'oxyde nitrique de la fumée de cigarette Download PDF

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Publication number
EP0250806A2
EP0250806A2 EP87106954A EP87106954A EP0250806A2 EP 0250806 A2 EP0250806 A2 EP 0250806A2 EP 87106954 A EP87106954 A EP 87106954A EP 87106954 A EP87106954 A EP 87106954A EP 0250806 A2 EP0250806 A2 EP 0250806A2
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EP
European Patent Office
Prior art keywords
filter element
dispersion
substrate
making
chemically
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP87106954A
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German (de)
English (en)
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EP0250806A3 (fr
Inventor
Michael Dennis Lelah
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hercules LLC
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Hercules LLC
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Filing date
Publication date
Application filed by Hercules LLC filed Critical Hercules LLC
Publication of EP0250806A2 publication Critical patent/EP0250806A2/fr
Publication of EP0250806A3 publication Critical patent/EP0250806A3/fr
Withdrawn legal-status Critical Current

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    • A—HUMAN NECESSITIES
    • A24—TOBACCO; CIGARS; CIGARETTES; SIMULATED SMOKING DEVICES; SMOKERS' REQUISITES
    • A24D—CIGARS; CIGARETTES; TOBACCO SMOKE FILTERS; MOUTHPIECES FOR CIGARS OR CIGARETTES; MANUFACTURE OF TOBACCO SMOKE FILTERS OR MOUTHPIECES
    • A24D3/00—Tobacco smoke filters, e.g. filter-tips, filtering inserts; Filters specially adapted for simulated smoking devices; Mouthpieces for cigars or cigarettes
    • A24D3/06—Use of materials for tobacco smoke filters
    • A24D3/14—Use of materials for tobacco smoke filters of organic materials as additive
    • A—HUMAN NECESSITIES
    • A24—TOBACCO; CIGARS; CIGARETTES; SIMULATED SMOKING DEVICES; SMOKERS' REQUISITES
    • A24D—CIGARS; CIGARETTES; TOBACCO SMOKE FILTERS; MOUTHPIECES FOR CIGARS OR CIGARETTES; MANUFACTURE OF TOBACCO SMOKE FILTERS OR MOUTHPIECES
    • A24D3/00—Tobacco smoke filters, e.g. filter-tips, filtering inserts; Filters specially adapted for simulated smoking devices; Mouthpieces for cigars or cigarettes
    • A24D3/06—Use of materials for tobacco smoke filters
    • A24D3/08—Use of materials for tobacco smoke filters of organic materials as carrier or major constituent
    • A—HUMAN NECESSITIES
    • A24—TOBACCO; CIGARS; CIGARETTES; SIMULATED SMOKING DEVICES; SMOKERS' REQUISITES
    • A24D—CIGARS; CIGARETTES; TOBACCO SMOKE FILTERS; MOUTHPIECES FOR CIGARS OR CIGARETTES; MANUFACTURE OF TOBACCO SMOKE FILTERS OR MOUTHPIECES
    • A24D3/00—Tobacco smoke filters, e.g. filter-tips, filtering inserts; Filters specially adapted for simulated smoking devices; Mouthpieces for cigars or cigarettes
    • A24D3/06—Use of materials for tobacco smoke filters
    • A24D3/16—Use of materials for tobacco smoke filters of inorganic materials

Definitions

  • This invention relates to a method for making a chemically-treated filter element for selective filtration of cigarette smoke.
  • Fiber based filter elements are well-known and have been used in the cigarette manufacturing field for at least 40 years. While various synthetic fiber and fiber mixtures have been tried and evaluated in the market place, most cigarette filter elements continue to include cellulose acetate-based fibers.
  • Synthetic fibers particularly fibers of polyolefins such as polypropylene are easily drawn to a much smaller denier than cellulose acetate-based fibers, offering improved filter efficiency without simultaneous loss of strength needed for crimping and high speed production.
  • Such fibers also have disadvantages. These stem mainly from the fact that a substrate, such as an open or bloomed tow is relatively inert and not readily wetted or softened by most adhesive/­plasticizer or other hydrophilic-type modifier formulations.
  • U.S. Patent 3,428,056 points out that the addition of water-soluble inorganic salts that effectively remove hydrogen cyanide from cigarette smoke lead to non-­uniform powder distribution and poor filtration efficiency. That patent attempts to deal with the problem by using poly­olefin powders that have been coated with inorganic salts such as sodium and potassium carbonates, the powders being vibrated onto cellulose acetate tow that has been previously treated with a bonding agent such as glycerol triacetate and that is then compacted and wrapped to form a filter rod.
  • inorganic salts such as sodium and potassium carbonates
  • U.S. Patent 3,6l8,6l9 deals with the problem of removing by dispersing metal oxides such as zinc oxide, ferric oxide and cuprous oxide in the cellulose acetate solution from which the cellulose acetate tow used in the filters is spun, and then treating the tow with certain organic "activating agents", including glycerol triacetate,to make the tow fila­ments permeable to hydrogen cyanide.
  • metal oxides such as zinc oxide, ferric oxide and cuprous oxide
  • organic "activating agents" including glycerol triacetate
  • U.S. Patent 3,6l8,6l9 discloses the use of a mixture of zinc acetate and other compounds to impregnate a base of alum­inum oxide, which is the dispersed in particulate form in filter fibers such as those of cellulose acetate.
  • Many other U.S. patents have defined and attempted to solve the problem of incorporating zinc compounds in cigarette filter material. None of them apparently have addressed the problem of treat­ing polyolefin fiber-containing substrates with such com­pounds.
  • a method for making a chemically-treated filter element for cigarettes in which a cigarette filter element obtained from a conventional filter­rod-making apparatus using, as garniture feed, a polyolefin fiber-containing substrate, is treated with a zinc compound, such as zinc oxide or zinc acetate as an active modifier com­ponent in order to remove nitrogen oxide and nitrogen oxide by-products from cigarette smoke, characterized in that a non-­ionic solution or dispersion containing zinc oxide or zinc acetate is applied to all or part of the substrate in the garniture feed, the non-ionic solution or dispersion also con­taining as a dispersant a polyoxyalkylene derivative of a sor­bitan fatty acid ester, a monoester of a polyhydroxyalcohol, or a diester of a polyhydroxy alcohol, or containing a mixture of the said dispersants.
  • a zinc compound such as zinc oxide or zinc acetate
  • the non-ionic solution or dispersion will be referred to as a non-ionic "spin solution" in accordance with usage in the art.
  • the nonionic spin solution contains about 0.l wt%-l0 wt% and preferably 0.5 wt%-l0 wt% of one or more of the surfactants.
  • the surfactants in the non-ionic spin solu­tion are ethoxylates, carboxylic acid esters, glycerol esters, polyoxyethylene esters, anhydrosorbitol esters, ethoxylated anhydrosorbitol esters, ethoxylated natural fats, oils and waxes, glycol esters of fatty acids, polyoxyethylene fatty acid amides, polyalkylene oxide block copolymers, and poly(oxyethylene-co-oxypropylene).
  • the amount of the modifier components is ap­plied is about l wt%-l0 wt% based on fiber weight.
  • substrate denotes a fiber-­containing or fibrillated film-containing component suitable for use as garniture feed for a filter rod-making apparatus.
  • Substrates may be (a) open polyolefin-containing fiber tows, (b) open ribbons of a nonwoven polyolefin- containing material or (c) open webs of fibrillated polyolefin films combined with active modifier component.
  • the open fabric ribbon can comprise up to about l00% and preferably l0% - l00% by weight of polyolefin (mono-, bi-, or tri-component) fiber identified generally as staple polypropylene, or may consist of webs having filaments of mixed denier, or combination of fibers such as (a) polypro­pylene/polyethylene, polypropylene/polyvinylidene chloride, polypropylene/cellulose acetate, polypropylene/ rayon, poly­propylene/nylon, cellulose acetate/polyethylene, plasticized cellulose acetate, polypropylene/paper; or (b) polypropylene/­polystyrene/polyethylene, and the like, in a preferred ratio of about (a) l0% - 90%/90% - l0% or (b) l0% - 90%/45% - ­5%/45% - 5% by weight of fiber.
  • polyolefin mono-, bi-, or tri-component
  • the substrate is an open polyolefin fiber web or open tow or nonwoven ribbons of polypropylene or poly­ethylene.
  • Such garniture feeds can usefully include up to about four substrate components, one or more of which have active modifier component applied onto one or both faces, the manner and number of faces treated depending upon the desired filter efficiency, taste, feel, hardness, and draw of the resulting filter element.
  • the garniture feed is fabricated, in situ, (i.e. im­mediately upstream of the garniture) or produced and stored before use. It is also found useful, for present purposes to use one or more nonwoven fabrics of the same or different fiber composition and denier, particularly when not all of the substrates are used as a carrier or posses different absorbing properties for the active modifier component.
  • the polyolefin-containing substrate is pre­treated by corona or plasma discharge before application of the solution or dispersion of the active modifier component.
  • Conventional filter rod-making apparatus suitable for carrying out the method according to the invention, comprises a tow trumpet, a garniture, shaping means, wrapping means, and cutting means in accordance with well-known components and processes, described, for instance, in U.S.Patents 3,l44,023 and USP 2,794,480. If desired, however, obvious modifications can be made to facilitate in-situ or prior spraying, dipping, printing or other traditional application of modifier com­ponents prior to formation of the filter plug.
  • baled substrate can be prepared for use by continuous dip coating or by contact with one or more printing rolls fed from reservoirs of the active components, followed by conventional drying steps effected by nip rolls, heated drying rolls, ovens, and the like, at temperatures generally within the range of about 70°C-l25°C.
  • nonwoven material from fibers within a wide denier range can be obtained using art-recognized techniques.
  • such material falls within a weight range of about l0-50 grams per m2, and a ribbon width of about 4 ⁇ - l2 ⁇ will generally assure successful passage through the garniture of a conventional filter rod-making apparatus at production speeds.
  • the garniture feed may usefully comprise one and up to about 4 or even more substrate com­ponents of identical or different weight, dimensions, bond­ing, absorption, fiber composition, and denier, and such substrate can be introduced with the components wholly or partly in register.
  • substrate can be introduced with the components wholly or partly in register.
  • one rela­tively lightly thermally bonded open fabric, tow, or fibril­lated film in register with one, or between two nonwoven fabrics is found to offer a high degree of flexibility for adapting the resulting filter element to a variety of market needs, including cost, filter draw, and hardness parameters.
  • Cost-wise, open fiber tows and nonwoven ribbons are found especially useful since they permit the use of rela­tively cheap polyolefin webs of mixed denier and type, and simplifying the precise distribution of modifier components within a filter element without the need for abandoning the above-listed art-recognized techniques and equipment such as printing rolls and spray heads for coating one or more non­wovens, before forming a filter plug.
  • Supplemental components in addition to the above-­defined active modifier components, can also be employed as, for instance, solutions, emulsions, suspensions or disper­sions of one or more humectants generally exemplified by poly­hydric alcohols such as glycerols, gylcols, etc.; flavors and perfumes such as ketoses and polysaccharides, including wintergreen, spearmint, peppermint, cinnamon, fruit flavors, etc., and additives as otherwise found in USP 4,485,828; medicines, such as menthol and decongestants, etc.
  • solutions, emulsions, suspensions or disper­sions of one or more humectants generally exemplified by poly­hydric alcohols such as glycerols, gylcols, etc.
  • flavors and perfumes such as ketoses and polysaccharides, including wintergreen, spearmint, peppermint, cinnamon, fruit flavors, etc., and additives as otherwise found in USP 4,
  • each treated substrate is dried to a moisture content of less than about 3% before conversion into filter elements.
  • the filter element and its active additive components can be usefully shielded, as de­sired, from direct contact with the lips by applying the active component onto a tow or nonwoven fabric which is, in turn, sandwiched within two or more untreated nonwoven fabrics of lesser permeability (Ref. Fig. 3).
  • the resulting filter element can be externally coated with cork or similar inert heat-insulating material (not shown).
  • the amount and effectiveness of modifier(s) applied to filter elements in this way is determined substantially by the sub­strate width and number of substrates which are fed simultan­eously into a garniture, as well as the amount of treated surface exposed to cigarette smoke in the filter element.
  • both treated and untreated fabric ribbon can be usefully wrapped using regular plug wrap paper having a weight within a range of about 25-90 g/m2 or higher, as desired.
  • Figures l-3 diagrammatically represents a conven­ tional cigarette filter rod-making apparatus modified to con­vert substrates prepared in accordance with the instant inven­tion into filter elements
  • Figures 2-4 diagrammatically represent further modifications and improvements within the instant invention, whereby one or more tows or ribbons of a nonwoven in register or partial register, are easily impreg­nated with one or more active modifier components by spraying or dipping and the use of multiple substrates favors increased filter element bulk and improved crush resistance, or hard­ness.
  • a single con­tinuous substrate such as open fiber tow, fibrillated film or ribbon of nonwoven fabric (l0) is fed from feed reel (ll) or a bale (not shown) through spray heads (20) feedably connected to feed lines (2l) from outside sources (not shown) to apply active modifier component(s) (22).
  • the treated substrate is then dried by heated air drying rolls (l2) and means (not shown) to obtain a desired degree of dryness, and then led by guide rolls (l7) into a garniture trumpet (l5) and garniture (l4) of a cigarette filter rod manufacturing apparatus (l) comprised of a garniture section (2) including (but not showing) means for shaping and retaining the substrate feed, wrapping means, and cutting means for converting the wrapped plug or rod into filter element (l6); the wrapping means is conveniently supplied with tow wrap from wrap feed reel (5) supported by support rolls (l9) and moved onto continuous garniture belt (3) for introduction into the apparatus.
  • the apparatus comprises conventional means for sealing the tow wrap around a filter plug (not shown), the later being cut by cutting means (not shown) into cylindrical filter elements (l6) of desired length (normally 90 mm), be­fore removal by filter chute (l8) (shown in fragment) for packing in container (23).
  • Figure 2 diagrammatically demonstrates a further suit­able arrangement for separately applying active modifier component(s) onto two open substrates of the same or differ­ent type whereby spray heads (20A) fed by connecting feed lines (2lA) apply active modifier component(s) (22A) (identi­cal or otherwise) onto substrates (l0A, l0B), fed in register and dried using air and heated rolls (l2A) before passage through garniture (l4A) of rod-making apparatus (lA), to form filter elements (l6A) as before.
  • spray heads (20A) fed by connecting feed lines (2lA) apply active modifier component(s) (22A) (identi­cal or otherwise) onto substrates (l0A, l0B), fed in register and dried using air and heated rolls (l2A) before passage through garniture (l4A) of rod-making apparatus (lA), to form filter elements (l6A) as before.
  • Substrates (l0A and l0B), are fed from feed rolls (llA) and (llB) or bales (not shown) and conveniently brought into register at heated nip rolls (l2A), then guided by guide rolls (l7A) into garniture (l4A), the garniture feed or substrate components shown being simi­larly defined by arabic numbers in each of Figures l-3.
  • Figure 3 diagrammatically demonstrates a still further modification of the equipment and process of Figures l and 2, whereby several substrates of the same or different types (l0C, l0D, and l0E) from reels or boxes (not shown) are fed through a nip created by heated rolls (l2B), depending upon the degree of filtration desired, the middle substrate (l0D) can be varied in width and preferably posses higher absorp­tion or adsorption properties then external untreated sub­strates (l0C and l0E).
  • substrate (l0D) is sprayed on both sides to fully expose it to one or more active modi­fier components (22B) by spray heads (20B) fed from feedlines (2lB), substrate (l0E) preferably being widest and arranged so as to catch surplus drip or misdirected active modifier not captured by ribbon (l0D), all three substrates are then air dried by passing in register through heated nip rolls (l2B), as before, and directed by guide rolls (not shown) into the garniture of a filter rod apparatus in the manner of Figures l and 2.
  • FIG 4 is a diagrammatic representation of a further modification in which one or more substrates (not shown) can be separately fed from a bale or box (24C), passed over guide rolls (l7C), and dipped into a reservoir (25C) containing active modifier component (22C), then passed through nip rolls (26C), through a heating oven (27C), through drawer rolls (28C) and a three step drying oven (29C), to garniture (l4C) of a cigarette rod manufacturing apparatus in the manner of Figures l-3, supra or boxed for future use.
  • preparation of the tow is conveniently carried out in the usual way by drawing the fiber from one or more creels through a fluid bulking or texturing jet and then handled as noted above.
  • Substrates which are employed in the above manner can usefully be of a variety of synthetic filaments as noted above.
  • polyesters, polyamides, acrylics, as well as polypropylene or cellulose acetate materials Due to its relatively low density, compared to other synthetic fiber-forming material and excellent spin properties, combinations of filament-forming copolymers of propylene with ethylene or other lower olefins monomers are preferred tow, ribbon and fibrillated film material.
  • the bulk denier of a tow for carrying out the present invention can conveniently fall between about 2,000 and l0,000.
  • this substrate can be supplied as a crimped fiber from a single creel or bale, or a composite of several creels or bales combined and passed through a fluid jet simultaneously.
  • Active modifier compositions within the definition of C-l, C-2 and C-3 (Table I) are applied as finish compositions to substrates TS-l, TS-2 and TS-3 in the manner indicated in the following Examples.
  • test filters described in Examples I and II as F-l, FC-l, F-2 and FC-2 are tested on a filter testing device comprising a valved constant pressure NO/N2 gas source flowably secured on the downstream side by glass and Tygon tubing to a plastic filter holder which is connected, on its downstream side, to a Drager Tube (*3) prepacked with Cr(VI) catalyst and p,p-diamino, m,m-dimethly biphenyl as a color indicator for detecting nitrous oxide (NO). *3. National Drager Inc., Pittsburgh, Pennsylvania.
  • test gas contains l00 ppm NO in nitrogen gas, and the filter is exposed for thirty (30) minutes at a 50 ml/­minute flow rate. Test results are reported in Table II below.
  • test filters described in Examples I and II as F-3, FC-3, F-3A, FC-3A are taped to Camel light tobacco rods and smoked on a Borg-Waldt smoking machine at a rate of eight (8) two second 35 ml puffs with a 58 second period between puffs.
  • the machine exhaust is connected directly to a Chem Lot UK nitric oxide analyzer (using chemilumenescence properties for detecting NO concentration using a 50, l00 and l,000 ppm NO/N2 calibration standard. Test results are reported in Table II below.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Cigarettes, Filters, And Manufacturing Of Filters (AREA)
  • Solid-Sorbent Or Filter-Aiding Compositions (AREA)
  • Nonwoven Fabrics (AREA)
  • Treating Waste Gases (AREA)
  • Filtering Materials (AREA)
EP87106954A 1986-06-30 1987-05-13 Procédé et dispositif pour éliminer l'oxyde nitrique de la fumée de cigarette Withdrawn EP0250806A3 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US88060486A 1986-06-30 1986-06-30
US880604 1986-06-30

Publications (2)

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EP0250806A2 true EP0250806A2 (fr) 1988-01-07
EP0250806A3 EP0250806A3 (fr) 1988-06-01

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EP87106954A Withdrawn EP0250806A3 (fr) 1986-06-30 1987-05-13 Procédé et dispositif pour éliminer l'oxyde nitrique de la fumée de cigarette

Country Status (4)

Country Link
EP (1) EP0250806A3 (fr)
JP (1) JPS6374476A (fr)
CN (1) CN87104595A (fr)
BR (1) BR8703293A (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5076295A (en) * 1989-09-29 1991-12-31 R. J. Reynolds Tobacco Company Cigarette filter
US5105834A (en) * 1989-12-18 1992-04-21 R.J. Reynolds Tobacco Company Cigarette and cigarette filter element therefor
US5246017A (en) * 1990-11-06 1993-09-21 R. J. Reynolds Tobacco Company Cigarette and cigarette filter element therefor
EP0659355A2 (fr) * 1993-12-22 1995-06-28 Hoechst Aktiengesellschaft Filtre pour l'élimination des oxides d'azote de la fumie de tabac
US9642394B2 (en) 2011-07-21 2017-05-09 British American Tobacco (Investments) Limited Porous carbon and methods of production thereof

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104188105A (zh) * 2014-08-26 2014-12-10 云南中烟工业有限责任公司 一种烟用缓释香料片和吸附片的制备方法及设备

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE686826A (fr) * 1965-09-20 1967-02-15
US3428056A (en) * 1965-07-21 1969-02-18 Eastman Kodak Co Tobacco smoke filter incorporating coated polyolefin additive
US3618619A (en) * 1970-03-03 1971-11-09 Eastman Kodak Co Tobacco smoke filters
DE2365263A1 (de) * 1973-05-16 1974-12-05 British American Tobacco Co Zigarettenfilter od. dgl
GB1400197A (en) * 1972-01-26 1975-07-16 British American Tobacco Co Tobacco smoke filter additive

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3428056A (en) * 1965-07-21 1969-02-18 Eastman Kodak Co Tobacco smoke filter incorporating coated polyolefin additive
BE686826A (fr) * 1965-09-20 1967-02-15
US3618619A (en) * 1970-03-03 1971-11-09 Eastman Kodak Co Tobacco smoke filters
GB1400197A (en) * 1972-01-26 1975-07-16 British American Tobacco Co Tobacco smoke filter additive
DE2365263A1 (de) * 1973-05-16 1974-12-05 British American Tobacco Co Zigarettenfilter od. dgl

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5076295A (en) * 1989-09-29 1991-12-31 R. J. Reynolds Tobacco Company Cigarette filter
US5105834A (en) * 1989-12-18 1992-04-21 R.J. Reynolds Tobacco Company Cigarette and cigarette filter element therefor
US5246017A (en) * 1990-11-06 1993-09-21 R. J. Reynolds Tobacco Company Cigarette and cigarette filter element therefor
EP0659355A2 (fr) * 1993-12-22 1995-06-28 Hoechst Aktiengesellschaft Filtre pour l'élimination des oxides d'azote de la fumie de tabac
EP0659355A3 (fr) * 1993-12-22 1997-04-16 Hoechst Ag Filtre pour l'élimination des oxides d'azote de la fumie de tabac.
US9642394B2 (en) 2011-07-21 2017-05-09 British American Tobacco (Investments) Limited Porous carbon and methods of production thereof

Also Published As

Publication number Publication date
EP0250806A3 (fr) 1988-06-01
CN87104595A (zh) 1988-01-13
JPS6374476A (ja) 1988-04-04
BR8703293A (pt) 1988-03-15

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