IL25839A - Cigarette filter - Google Patents

Description

CIGARETTE This invention relates to a new and improved cigarette More this invention relates to a novel cigarette filter having high overall ef coupled with a selective extraction While filtering means in combination with cigarettes have long been in it was generally believed that smoke filtration was of little actual value in terms of reducing harmful or toxic particulate matter present lowj in tobacco Notwithstanding the efficiency generally found in cigarette their use by both domestic and has grown at a great the acceptance of filters due to an esthetic effect and because filters serve to avoid the taste of loose tobacco unpleasant to In recent y ars much concern has been voiced by governmental and medical groups over the possibility that there may be a causal relationship between excessive smoking and as well as respiratory ailments and heart The rate of incidence of such diseases has been said to be greater in those who smoke excessively and the problem now appears to be one which affects the general welfare of the Research engendered by the possibility of the causal relationship between smoking and cancer has indeed uncovered certain chemical compounds in the mainstream of cigarette tobaoco smoke which are Other compounds known to function as promoters or potentiators for carcinogens have also been detected in significant concentrations in cigarette tobacco Elimination of the known harmful constituents of tobacco smoke has been recognized as a problem thought to be caused by excessive The smoke of cigarettes is normally classified as being the mainstream and the The mainstream is inhaled by the smoker and may be identified as an aerosol with billions of particles per cubic These particles have a median size of about microns and comprise the vast portion of carcinogens and potentiators of carcinogens present in the These compounds in particulate form may broadly be classified as aromatic aliphatio aldehydes and Of the aromatic hydrocarbons and phenols are thought to exert the greatest toxic It an object of this invention to provide novel cigarette filters which possess a superior A further object of this invention is to provide novel cigarette filters which extract a high amount of the total particulate matter in tobacco smoke and for which aromatic hydrocarbons and present in the particulate matter show a high These and other objects of this invention are broadly accomplished by employing as the filter material for cigarette smoke fibers of a polymer of acrylonitrile which have an average diameter of between about microns to about 10 It has been discovered that the fibers of acrylonitrile polymers provide an excellent and highly efficient filtration system for cigarette smoke not only because of the gross removal of harmful particulate Such combination of properties has not been observed of fine commercial denier fibers of acrylonitrile polymers or by use of fine fibers of cellulose the overall ef ectiveness of the novel filter of this vention is due to the combination of superfine fiber structure and acrylonitrile polymer The employed in the cigarette are usually fine as above They may be formed by introducing a acrylonitrile polymer or blend of polymers in solution onto the surface of a disc rotating at a high velocity such that millions of droplets are formed as centrifugal force removes the solution from the face of the Surrounding the rotating disc is a high velocity fluid such as which travels parallel to the axis of the The droplets emitting from the disc surface are caught up in the fluid stream such that they are attenuated and coagulated by evaporation of the polymer solvent to form tiny microfibers of striking A moving screen or other device may be placed in the path of the fluid stream to collect the freshly coagulated fibers as a matt or The distribution of fiber diameters and circular fiber exhibit substantial Essentially the solvent may be practiced to preclude solvent bonding and solvent residues which may otherwise tend to give the filter material an undesirable The solvent for polymers of this type are well known in the art and they are preferably selected from the organic polar solvents such as ethylene The polymer composition necessary for the effective overall performance of the filter are the forming polymers comprising at least 50 percent and preferably at least percent by weight of The polymer may be a homopolymer or an interpolymer of acrylonitrile with one or more ethylenically unsaturated monomers Representative of such monomers are acrylic methacrylic methyl methyl vinylidene vinyl vinyl vinyl methyl vinyl pyridine and the The polymers of acrylonitrile may be polymer blends as For polyacrylonitrile may be blended with a copolymer of acrylonitrile and vinyl The web of microfibers above described may be fashioned into a roll to form a filter or cut and then and attached to the tobacco containing portion of the This invention relates to the particular polymeric composition and fibrous nature of the cigarette filter and can be adapted to various methods known in the art for the manufacture of Although the microdenier acrylonitrile based fibers must be present in the filter acoording to this they may be employed in combination with other filter For individual plugs of cellulose acetate and a plug made from fibers of this invention may be combined as a bicomponent the filter may be impregnated or partially coated with charcoal dust or chemical compounds which in themselves have selective EXAMPLE To compare efficiency of the filter of this invention with a commercial cellulose acetate filter 10 cigarettes containing a 17 filter of cellulose acetate were smoked on a smoking machine by drawing off twelve puffs of smoke at 30 second The particulate matter passing through the filter and that captured in the filter were analyzed for tar and Identical determinations were run on cigarettes made according to this invention wherein a 17 rod of a matt of microdenier having an average fiber diameter of about microns was placed on a cigarette from which the cellulose acetate filter had been The polymer compcsition from which the micro fiber were prepared was in this case a copolymer taining about 93 percent of aorylonitrile and about 7 percent by weight of vinyl The results are listed in Table I and show greatly increased efficiency over the conventional cellulose acetate Other embodiments of this invention will be readily apparent to those skilled in the TABLE I TAR AMD NICOTINE EVALUATION DATA Tar Weight Weight filter Weigh Filter Material In Filter In Trap Efficiency In Fil filter 177 Cellulose Acetate filter 177 ttAcrylonitrile Microfiber insufficientOCRQuality

Claims (1)

1. A filter cigarette having a filter element characterized a matt or web eompoeed of a polymer of the diameter of polymer fibere ranges from 1 The filter of 1 characterized that the of at percent tt of filter claim 2 that said is of and to 15 peroent of at leaet one tip cigarette claim In that said vinyl filter tip cigarette of 1 characterised in that the average diaiseter of fibers of a of la 3 Λ filter tip hereinbefore described insufficientOCRQuality