US3527235A

US3527235A - Tobacco smoke filter device

Info

Publication number: US3527235A
Application number: US731866A
Authority: US
Inventors: Paul H Fidelman
Original assignee: Matra Corp
Current assignee: Matra Corp
Priority date: 1968-05-24
Filing date: 1968-05-24
Publication date: 1970-09-08
Anticipated expiration: 1987-09-08

Description

Sept. 8, 1970 P. H.-FIDELMAN 3,527,235

TOBACCO SMOKE FILTER DEVICE Filed May 24, 1968 E 1w;- Z v I E r E a 6 a r 9 mum-kw 4 k 6 H65.

744 7 1 \Y %z. i

5 0 \m 8 Am /1W 7 7 70 FIGS.

11 2 FIGJO. 1 & ll H\\\\\\\ M United States Patent O 3,527,235 TOBACCO SMOKE FILTER DEVICE Paul H. Fidelman, Bayside, N.Y., assignor to Matra Corporation, New York, N.Y., a corporation of New York Filed May 24, 1968, Ser. No. 731,866 Int. Cl. A24d 1/04; A241? 7/04 US. Cl. 131-264 4 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION The harmful physiological effects of volatile constituents contained in tobacco smoke have long been recognized. This is well known and it is appreciated that tobacco smoke contains certain solid tar constituents and health-affecting, volatile materials of the nicotine class which tend to physiologically irritate the smoker and impair his health. In the past, various attempts have been made to obviate these harmful materials from tobacco smoke by using various types of tobacco smoke filters attached to the smoking device. Usually these filter elements are placed at the butt end of a cigarette or in the stem portion of a pipe or cigarette holder or some other suitable location depending upon the character of the smoking implement. These filters, which normally consist of a bundle of cellulosic fibers or convoluted creped paper formed into a cylindrical plug, are designed to remove varying proportions of the droplets and solid particles passing through them and thereby reduce the amount of undesirable materials reaching the mouth of the smoker. This solid particle filtering action is accomplished by a combination of diffusional, impactive and direct collision of the droplets with the filter materials. Upon collision the droplets are retained in the filter by title surface attraction between the extremely small particles and the relatively large filter material.

The danger to health from tobacco smoking has been so widely published that the attention of the US. Government has been alerted thereto; the question has even been the subject of investigation by sub-committees of the US. Congress. Results of tests conducted by the Federal Trade Commission laboratory on the tar and nicotine content of fifty-nine brands of cigarettes were published on Nov. 27, 1967.

Because of the adverse publicity attendant upon tobacco smoking, many types of filtering devices have been ofiered commercially as a protective measure against the harmful, physiological effects of the volatile constituents contained in tobacco smoke. Although it is doubtful whether any of the currently available filter devices actually eliminate the health hazard, the aforementioned report published by the Federal Trade Commission Laboratory establishes that the presently commercially used filters on cigarettes substantially reduce the total particulate matter and nicotine.

Among the presently used filtering devices, are the following types:

3,527,235 Patented Sept. 8, 1970 (1) Cellulose adsorbent filters;

(2) Charcoal impregnated filters;

(3) Cellulose and air-intake filters; and (4) Chemical filters.

Cellulose and other fibrous filters work on the principle of entrapment and condensation. It will be apparent however, from the report published by the Federal Trade Commission Laboratory that while many filters cut down the percentage of irritants, a safe level of total particulate matter and nicotine has not been reached.

Filters using activated charcoal or other well-known adsorbents, such as alumina, natural or synthetic clay, and silica gels, have proved to be effective to some extent in removing ciliary depressants from the vapor phase of cigarette smoke, but their use has some definite disadvantages. For example, such adsorbent additives indiscriminately remove from the tobacco smoke not only certain obnoxious or toxic components, but many other components as well, and which are necessary to maintain the desired flavor and aroma of the smoke. In the case of activated carbon, the removal of these flavoring agents imparts an undesirable taste to the smoke that is commonly referred to as carbon taste.

Furthermore, since th adsorption of vapors by these materials is based on physical phenomena which in turn are dependent upon temperature and pressure, many of the adsorbed vapors, including those that are deleterious, may later be released in concentrated quantities as the burning zone of the cigarette approaches the filter during the smoking of the cigarette. If enough carbon is used in the filter to compensate for this deficiency, the cigarette becomes, for all practical purposes, unsrnokable.

On the other hand, the cellulosic filter with air intake proved unsatisfactory because of the excessive pull or draw needed to pull the smoke through the filter causes loss of flavor and taste.

Chemical filters propose to reduce chemically the materials that are adsorbed in an attempt to eliminate the aldehyde vapors and other irritating gaseous constituents. The question with these chemical filters, however, is Whether these chemical additives are not by themselves harmful in addition to a possible effect upon the flavor.

Efforts have also been made to reduce the temperature of the smoke inhaled by the smoker, presumably as an adjunct to the more eltective stripping of nicotine and tars from the smoke. Many of the efforts made in this direction thus far have, however, not proved fully satisfactory in that it appears to be difiicult to achieve an optimized balance between the flavor sought by the smoker and the desired reduction of the content of nicotine and tar.

Among the objects of the invention, therefore, is to provide a device which will achieve an optimized balance between the flavor sought by the smoker and at the same time attains increased removal of tar particulate matter, nicotine and other deleterious substances in the tobacco smoke and with the normally accepted draw or pull on the smoking device.

SUMMARY OF THE INVENTION In terms of broad inclusion, the invention contemplates a structure forming a plenum chamber or smoke reservoir of predetermined volume for the smoke; and a porous extracting wall of predetermined porosity through which structure the smoke is drawn into and through a body of adsorbent material, when the smoke enters the plenum chamber, which is larger in volume than the smoke escape channels, increased turbulence and pressure is created as the smoke is drawn from the plenum chamber through the escape channels and the extraction wall with consequent increase in velocity of the vapor phase constituents of the smoke through the device until the smoke impinges against the fibrous material by which it becomes adsorbed, while the tar particulate matter becomes condensed and separated out and the particulate portion thereof collected in the plenum chamber and on the surface of the extraction wall.

It will be apparent, therefore, that a smoke filter made in accordance with the invention is constructed so as to take advantage of the aerodynamics of the smoke stream instead of depending on bulky adsorbent filtering materials. It will also be apparent that one of the advantages inherent in the invention is a filter of substantially reduced bulk. It will also be observed from the example included hereinafter that the amount of removal of tar particulate matter is substantially increased in comparison to the amount removed by the presently-used commercial filters.

In addition to the above-mentioned advantages, the new filter has an extremely simplified design, with consequent reduction in manufacturing cost.

In the accompanying drawing, wherein an illustrative embodiment of the invention is disclosed,

FIG. 1 is a longitudinal sectional view of a portion of a cigarette to which the improved filter device has been applied;

FIG. 2 is a face view of one of the laminations or disks of the filter;

FIG. 3 is a face view of a second lamination or disk of the filter;

FIG. 4 is a face view of the third lamination or disk of the filter;

FIGS. 5, 6 and 7 are respectively cross sectional views of the laminations or disks of FIGS. 2, 3 and 4;

FIG. 8 is an edge view of the laminated filter;

FIG. 9 is a laminated strip from which the filter units can be stamped out, and

FIG. 10 is a longitudinal sectional view through the strip shown in FIG. 9.

In FIG. 1 of the drawing is shown a portion of a conventional cigarette at 1, provided with the tobacco filling 2 contained in the conventional paper covering 3. Applied to the butt end of the cigarette is a tube or sleeve, composed of paper or other suitable material and shown at 4. The sleeve or tube 4 contains a packing or filling of a fibrous adsorbent material of cellulosic character.

The filter device of the present invention consists primarily of three main elements; namely, the disks or

membranes

6, 7 and 8 which are laminated or facially secured together, resulting in a form of plug and constituting the filter unit shown in FIG. 8. The disk 6, constituting one of the laminations of the filter, constitutes a collection chamber or plenum and is in the form of a ring or annulus, being thus provided with a relatively large central opening shown at 9 which is the collection chamber. The second disk or lamination shown at 7 which is an outlet member for the collection chamber, is foraminous or provided with a plurality of small holes 10, the total area of which is preferably less than the area of the opening 9. The third disk or lamination 8 is an extractor and is composed of a finepore filter paper and while it is pervious to the smoke it has not any purposely-formed holes. The two

disks

6 and 8 are the outermost layers of the unit, with the perforated disk 7 being sandwiched between them. The three disks are bonded or cemented together facially. They may be of diiferent thicknesses. That is to say, the disk 6 may be relatively thick; the disk 7 thinner and the disk 8 the thinnest of the three disks.

The filter units can be produced in various ways, such as for example, laminating three strips 11, 12 and 13 (FIGS. 9 and 10) together, the strips 11 and 12 having been previously punched out with the required

apertures

9 and 10. The resultant laminated strip appears as shown in FIG. 9 and by die-cutting it on the dotted lines 14, the filter units, each composed of the three disks can be quickly and economically produced.

One of the filters, as shown in FIG. 8, may be placed within the filter tube 4 and disposed between the tobacco filling 2 and the cellulosic packing 5, or as shown in FIG. 1, a number of these units may be placed in the tube 4 between the tobacco and the cellulosic packing. In FIG. 1 two of the units are arranged in tandem in the tube 4 and in addition two

additional disks

6 and 7 have been included. This is one suggested way in which the units may be used but it is not obligatory since one or more of the units can be used etfectively.

The central aperture 9 in the disk 6 forms a collection chamber or plenum for the smoke which, after entering the chamber 9 passes through the apertures 10 in the smoke outlet disk 7 next encountering the extraction disk 8 and passing therethrough, the smoke then passing through the cellulosic packing 5 to the mouth of the smoker.

The filtering device as herein described has been submitted to a consulting and analytical chemical laboratory and the report therefrom showing the increase in the removal of tar, particulate matter and nicotine is as follows:

ISAMPLES Four True cigarettes provided with filters in accordance with this invention; five Tareyton mm. cigarettes also provided with these filters.

True cigarettes are marked A; Tareyton marked B.

AN ALYS IS Four cigarettes were smoked by FTC method and total particulate matter found. Nicotine then determined.

(A) True with the special filters Smoked to 33 mm. butts Pressure (dra'w)l315 cm. water Average number puffs-73 Total particulate matter found10.2 mg./ci garette Nicotine found--0.60 mg./ cigarette Calculated tars per cigarette: T.P.M.-moisture-nicotine-86 mg.

FTC reports 12.8 mg. tars and 0.65 mg. nicotine in True (B) Special filters (as per invention) in Tareyton, 85 mm. Smoked to 30 mm. butt length Pressure (draw)'1316 cm. water Average number putfs=8.8 Total particulate matter-16] mg./ cigarette Nicotine'0*.75 mg./ cigarette Calculated tars per cigarette:

tinel4.2 mg. FTC reports 17.5 mg. tars and 1.07 mg. nicotine per 85 mm. Tareyton filter cigarettes Assume that T.P.M. has 10% moisture average.

While it is herein suggested that the filter device be employed in connection with cigarettes, it will be apparent that it can also be used in connection with cigarette or cigar holders, pipes etc. without departing from the spirit of the invention.

The True and. Tareyton cigarettes tested were identical with those listed in the report of the Federal Trade Commission Laboratory and referred to in column 1, line 56, and the FTC. figures for tars and nicotine are those in said report.

What I claim is:

1. A smoke filter including a relatively fiat and thick disk provided with a central opening through it defining a plenum chamber by the wall of such opening, a smoke escape disk in face-to-face contact with said thick disk and downstream thereof, said escape disk having relatively small openings providing escape channels for the smoke from the plenum chamber, and a fine-pore filter material disk in face-to-face contact with said smoke escape disk and downstream thereof and pervious to the gaseous constituents of the smoke but impervious to the particulate constituents thereof, said fine-pore filter material disk being thinner than said escape disk.

T. P.M.-moisture-nico- 2..A smoke filter according to claim 1, in which the 2,954,786 10/1960 Lebert 131264 disks are laminated together. 3,006,346 10/1961 Golding 131- 107 3. A smoke filter according to claim 1, wherein the 3,079,926 3/1963 Litchfield et a1. 13110.7 X disks are of different thicknesses; that with the central 3,251,365 5/ 1966 Keith et a1 131 10.7 aperture being thicker than that with the smaller holes, 5 3,318,312 5/1967 Curtis 13110.7 X and the third disk being thinner than the two other disks.

4. A tobacco smoke filter as defined in claim 1 compris- FOREIGN PATENTS ing, a tubular mouthpiece containing all of said disks and 677,137 12/1963 Canada. also a fibrous adsorbent material downstream of said 739,002 10/1955 Great Britain filter material disk.

References Cited UNITED STATES PATENTS 3,335,733 8/1967 Brooks 131 1o.s x U.S.C1.X.R. 2,386,684 10/1945 Hermanson, 15 131 10.5, 10.7

SAMUEL KOREAN, Primary Examiner J. H. CZERWONKY, Assistant Examiner