DE3201101A1 - Cigarette filter rod - Google Patents

Description

11168 / Dr.v.B / Ro.

CIGARETTE COMPONENTS LIMITED Friendly House, 21-24 Chiswell Street, London , England

Cigarette filter stick

The present invention relates to a cigarette filter rod according to the preamble of claim 1.

It is known that the proportion of harmful carbon monoxide (CO) in the smoke of a filter cigarette by a ventilated or air-diluted cigarette filter can be reduced. With the known Filter structures, however, the reduction in CO content is generally proportional to the degree of dilution of the Smoke with air, however, from a corresponding proportional reduction in the taste-forming contained in the smoke Components is accompanied. The desired high reduction in the CO content of the smoke required hence such a degree of air dilution that the smoke becomes unacceptably tasteless.

. The present invention accordingly has the object based on specifying a cigarette filter that lowers the CO content without excessive taste allowed.

This task is performed by a cigarette filter rod type mentioned with the characterizing features of claim 1 solved.

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A cigarette filter rod according to the invention thus contains a plug made of tobacco smoke filter material, a tubular wall aligned with this in the longitudinal direction, which extends up to extends to one end of the filter rod, and a casing surrounding the stopper and the tubular wall, so that the filter rod has a cavity which extends from the filter material plug and the center of the tubular Wall of its opening extends at one end of the rod. The envelope or the envelope and the tubular wall allow when in use of the filter rod this is drawn, the entry of external air from the side into the cavity.

In some embodiments, the tubular extends Wall or the tubular component up to the filter material plug α and consists of a porous, air-permeable material, e.g. tobacco smoke filter material, and the surrounding envelope is perforated and / or made of a naturally air-permeable material; the tubular Instead, the component can also be made from a naturally air-impermeable material (e.g. from a plastic or cardboard sleeve), which has through holes and the surrounding envelope can then be made of an air-permeable Consist of material and / or perforations that communicate with the holes in the tubular component, exhibit. If the tubular component or the tubular wall consists of an air-permeable material, It can also have through holes to facilitate the entry of outside air from the side.

In other embodiments, the tubular wall or the tubular component is spaced apart in the longitudinal direction from the filter material plug and the envelope allows the lateral entry of external air through

the envelope in the space between the plug and the tubular component. In this case, the tubular Component be impermeable, so that all ventilation takes place directly in the space mentioned, or the casing and the tubular wall can be designed as in the case of the embodiments described first above and allow some outside air to enter through the envelope and tubular member. As in In all embodiments, the envelope can be perforated and / or of an inherently air permeable material where lateral or radial penetration the air is desired.

The above-described embodiments of the present Filter rods are usually used in a filter cigarette on the wrapped tobacco by a Tip sheath to be attached; the tip cover will normally be made of a substantially air impermeable material Material exist in the area in which they are the tubular component and / or any Surrounding space between the plug and the tubular component, has a perforation.

The filter rods according to the invention usually occur essentially no outside air into the filter material plug from the side. The outside air that Entering the cavity laterally may be the only dilution air or ventilation that is required when in use of the present filter rods by the combination of the stopper, the tubular component and the casing is delivered. In the case of filter cigarettes which contain a filter rod according to the invention, this is the The cigarette paper surrounding the tobacco rod is preferably substantially impermeable to air, so that the air is thinned or ventilation when smoking essentially only through

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the filter rod takes place; if the cigarette paper is air-permeable to a significant extent, it can the degree of air dilution and CO removal when smoking the cigarette between the first and the change the last puff in an intolerable way and the smoke of the first puffs may have an intolerably low flavor content.

The various dimensions of the present filter rods (e.g. the length of the plug and the tubular Component and any space between them, and the thickness of the tubular component) and the structure and composition of the components can match the required properties, e.g. pressure drop, degree of Air dilution, filter efficiency, to be chosen accordingly; the filter properties are preferably corresponding selected the properties of the wrapped tobacco rod with which the filter is to be used, so that a filter cigarette with the required smoking properties results.

In the case of the present filter rods, the arrangement is preferably such that the majority (on the most advantageous the by far predominant part, i.e. essentially the whole) of the combination of the pressure drop caused by the filter plug and the tubular member is caused by the filter plug and correspondingly little (i.e. practically no) pressure drop through the part with the tubular wall, i.e. the tubular wall Component is caused.

Investigations of cigarettes which were provided with a filter according to the invention so that the open End of the cavity at the tobacco rod, have an unexpectedly high degree of CO reduction in the emitted

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Smoke relative to the degree of air dilution result without that the flavor components released have been excessively reduced.

In other embodiments of the invention, the filter cavity is to the mouth end of the filter cigarette open, the arrangement is preferably made so that the predominant Part or virtually all of the pressure drop across the filter upstream (i.e. towards the tobacco rod) of the Area where the outside air enters the cavity from the side, i.e. where the filter rod and the tobacco rod through a tip sheath having ventilation perforations, the latter preferably being downstream are arranged by the plug occurs. In such filter cigarettes according to the invention, in particular those where practically all of the pressure drop across the filter takes place upstream of the ventilation area, the tar release can be reduced more by air dilution than by mechanical filtration. the well-known conventional filters that have a low mechanical filtration efficiency with high air dilution are designed have the serious disadvantage that they generate too low a pressure drop, which is disappointing and unacceptable to the smoker.

In the present filter cigarette with the stopper part at the tobacco rod and the opening of the cavity at the end of the mouth can, on the other hand, have a high degree of ventilation at an acceptable level Total pressure drop and a desired low degree of retention (mechanical filtering) can be achieved.

The high dilution, low retention filter cigarettes according to the invention in which the cavity of the filter tip is open at the mouth end, can have lower CO / tar values than they do with conventional filters. With the filters according to the invention, in which the opening of the cavity is at the end of the mouth, another

speaking appearance can be achieved both before smoking and after smoking cessation; when the smoke flows out of this through the cavity, the material of the tubular component remains during smoking essentially uncolored and therefore retains its original state clean appearance.

The filter rods according to the invention are normally manufactured continuously in continuous pieces, the then cut to the final lengths required for handling and use. In the In the manufacture of filter cigarettes, a double-length filter rod is usually inserted between two tobacco rods and connected to them by the tip sheath; the arrangement thus obtained is then in the center cut to make two filter cigarettes; the initially produced continuous or endless The rod is usually cut into pieces several times (e.g. six times) the length, which are then sent to the filter cigarette maker are supplied, which these multiple filter units containing pieces into the units of duplicate Cut length to process them further in the manner mentioned above. The present invention relates This also applies to the endlessly manufactured rods made of alternating plugs and tubular components the surrounding envelope and the rods of multiple, e.g. double, length, which consist of these endless rods are obtained by inserting the former into the ones containing the plugs and / or the tubular components Sections cut across. The plugs and tubular components or sections can adjoin one another or be spaced in the longitudinal direction.

In the following, exemplary embodiments of the invention are explained in more detail with reference to the drawing.

■ ΙΟ It show:

Fig. 1 is a simplified longitudinal section of part of a Filter cigarette provided with a filter rod according to the invention, the filter cavity facing the tobacco is open;

2 shows a similar schematic view of a filter cigarette with another filter rod according to the invention, in which, however, the filter cavity is also open to the tobacco; and

3 and 4 corresponding simplified sectional views of filter cigarettes with filters according to embodiments of the invention in which the filter cavity is open towards the mouth end of the cigarette.

In the figures, the same components are given the same reference symbols but the figures are not to scale.

The filter cigarette shown in Fig. 1 contains an ordinary tobacco rod 2, which is of conventional, im essentially air-impermeable cigarette paper 4 wrapped and with a filter 6 according to one embodiment of the invention by a conventional tip wrapping made of substantially air-impermeable paper is. The filter 6 contains a plug 10 made of tobacco smoke filter material, which is adjacent to a tubular wall or a tubular component 12 made of tobacco smoke filter material and is connected to this by an air-permeable envelope 14. The plug 10 can be any conventional smoke filter element and e.g. made of corrugated paper or cellulose acetate fibers attached to the Points of contact are connected to each other (acetate cable)

exist, and the separate tubular member 12 can similarly made of smoke filter material. The tip cover 8 has an annular perforation on which the tubular component 12 in the circumferential direction vmgibt and ventilation holes 16 is formed through the. Smoking if pulled on the filter cigarette is, outside air through the envelope 14 and the tubular component 12 in one through the tubular component formed Höh] space 18 is pulled.

The plug 10 may, for example, be made from bonded cellulose acetate fibers (acetate tow) and made in accordance with the teachings of US Pat GB-PS 1 169 932 be made; the tubular component can consist of the same material and for example be made as described in the UK patent mentioned above, but with a central mandrel extends through the bore of the steam chamber, or as described in GB-PS 970,817. That tubular member 12, although it consists of a naturally air-permeable material, lateral or have radial perforations 20, as indicated by dash-dotted lines, to facilitate air dilution; such holes are essential to the aim of the present invention when the tubular member 10 consists of one of Consists of impermeable material in nature, as in other embodiments of the illustrated structure of the Case may be.

The embodiment of FIG. 2 differs from 1 in that the filter plug 10 and the tubular component 12 are separated by a gap 22 are, wherein the perforations 16 in the envelope 8 form a ring around this space. The length of the The filter plug 10 can be, for example, about 10 mm, that of the space 22 about 5 mm and that of the tubular

gene filter element or component 12 about 15 mm, and the The plug, tubular filter element and tip wrap can be of those mentioned in connection with FIG Materials exist.

The following is a specific example of a filter cigarette having a filter according to one described and illustrated Embodiment of the invention includes.

example

Filter cigarettes of the type shown in FIG. 1 were manufactured using normal (with conventional Cigarette paper 4 wrapped in low porosity) tobacco rods 2 with corresponding filter rods 6 using by conventional Ecusta tip wrapping material8, the latter being an impermeable paper, however, with three annular perforations 16 instead of the single perforation ring shown in the drawing was provided.

The stopper 10 consisted of a 10 mm long, unwrapped porous stopper made from bonded cellulose acetate fibers (Fiber denier 2.5; total denier 56 χ 10) with a pressure drop (PD) of about 67 mm; the tubular Component 12 consisted in a corresponding manner of connected cellulose acetate fibers; it had a length of 15 mm and a wall thickness of 1 to 2 mm; there were no side holes 20; the plug 10 and that tubular component 12 were encased by a plug to form a filter rod according to the invention held together from porous paper, which had an air permeability of 100 D (see definition below). the Filter cigarettes were designed for an air dilution (ventilation) of about 50% by volume.

320-101

Twenty such essentially identical filter cigarettes were opened on a standard smoking machine Perforations 16 smoked, a further twenty in a corresponding manner with closed perforations; the results were averaged and are listed in the following table. In the table, the pressure drop is in millimeters Water column, measured at a flow rate of 17.5 itil / second indicated; TPM means "total amount particulate substance "and WNF means" water- and nicotine free ".

Tabel

perforation closed open minded Ventilation Vol .% Through the filter rod 6 47.7 through the cigarettes paper 4 7.5 Pressure drop all over the cigarette 113 (mm WS) 89 67 Pressure drop across the filter rod (mm WS) 21, 0 TPM mg / cigarette 10.8 16.5 TPM (WNF) 8.6 1.55 Nicotine " 1.13 16.73 CO 4.99 37.5 Retained nicotine (%) 37.5 8.1 Puffs / cigarette 9.4 Percentage reduction TPM 48.6 ' TPM (WNF) 47.9 Nicotine 27.1 CO 70.1 CO / TPM (WNF) ratio 0.58

It can be seen that the present filter rods (ventilation openings or perforations 16 open) a excellent reduction in CO emissions is achieved, it is greater than that achieved with conventional ventilated Cigarettes can be achieved with the same percentage of air dilution.

In Figs. 3 and 4 filter cigarettes according to the invention are shown, which are essentially the same Components exist, as the embodiments according to Figures 1 and 2, however, the filter part is reversed so that the cavity 18 is open at the mouth end of the cigarette. at the filter cigarettes according to <Fig. 3 and 4 can therefore be the Filter plug 10, tubular member 12, cigarette paper 14 (wrapping) and tip wrapping 8 of each consist of the same materials and be dimensioned in the same way as in connection with FIGS. 1 and 2 has been explained. In any case, the dem. enveloped tobacco rod 2 adjacent stopper relatively little retain particulate matter, but practical cause all the pressure drop across the filter, and the air dilution through the perforations 1 6 in the cavity 18 takes place entirely downstream of the plug 10, so that a high level of air dilution and a low level of mechanical retention at an acceptably high level Total pressure drop can be achieved.

An air permeability of nD here means air permeability from η χ 1000 ml / minute / iO cm / 100 mm water column pressure and is determined by measuring the pressure; ρ in mm of water column determined by a flow of 1050 ml air /

Minute is generated by 10 cm paper, the air permeability is calculated according to the following equation:

Air permeability = 1050 χ 100 / p

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Claims (11)

PATENT LAWYERS DR. DIETER V. BEZOLD DIPL. ING. PETER SCHÜTZ DIPL. ING. 1WOLFGANG HEUSLER MARIA-THERESIA-STRASSE 22 POST BOX 86 O2 60 D-8OOO MUENCHEN 86 APPROVED BY THE EUROPEAN PATENT OFFICE EUROPEAN PATENT ATTORNEYS MANDATAIRES EN BREVETS EUROPEENS TELEPHONE 089/4 70 60 06 TELBEEG 522 638 seq. 23666 GB-PA 8101152 AT: 01/15/1981 11168 / Dr.v.B / Ro. 20 CIGARETTE COMPONENTS LIMITED Friendly House, 21-24 Chiswell Street, London, England Cigarette Extender Patent Claims 1.) Cigarette filter rod with a stopper made of tobacco smoke filter material , characterized by a tubular element in alignment with the plug (10) (12), which extends to one end of the rod, and through a plug (10) and the tubular, wall-like Element (12) surrounding envelope (8) so that the rod has a cavity (18) which extends from the stopper (10) extending through the center of the tubular element (12) and at one end of the rod is open, wherein the sheath (8) or the sheath and the tubular element (12) If the filter rod is pulled during use, outside air will enter the cavity from the side (18) enable. 2.) Filter rod according to claim 1, characterized in that the tubular element (12) extends away from the stopper (10) and consists of an air-permeable material (Fig. 1). 3.) Filter rod according to claim 1 or 2, characterized in that the tubular element is a perforated element adjacent to the plug (10). 4.) Filter rod according to claim 1, characterized in that the tubular element (12) is a separate element spaced longitudinally from the plug (10) and that part of the envelope (8), the space between the plug (10) and the surrounding tubular element (12), made of an air-permeable Material consists and / or is perforated (16) (Fig. 2). 5.) Filter cigarette, characterized by a filter rod according to one of the claims 1 to 4, the tubular element (12) between the stopper (10) and a tobacco rod (2) is located (Fig. 1). 6.) Filter cigarette, characterized by a filter rod according to one of the claims 1 to 4, the stopper (10) being located between the tubular element (12) and a tobacco rod (FIG. 3 and 4). 7.) filter rod, characterized in that that it consists of several cigarette filter rods according to FIG. 1, can be cut into these and stopper (10) Made from tobacco smoke filter material that deals with tubular Elements (12), which are aligned in the longitudinal direction with the stopper, alternate and with these from an envelope (8) are surrounded so that the rod has cavities (18) which extend from the respective plug through the Center of the adjacent tubular element and that the envelope or the envelope and the tubular elements allow lateral entry of outside air into the cavities. 8.) Filter rod according to claim 7, characterized in that g e that it has a cavity (18) at each end. 9.) Filter rod according to claim 7, characterized that it has a tobacco smoke filter plug (10) at each end. 10.) Filter rod according to one of claims 7 to 9, characterized in that each tubular element (12) adjoins the adjacent plug (10) and is perforated and / or made of an air-permeable Material. 11.) Filter rod according to one of claims 7 to 9, characterized in that the adjacent Plug (10) and tubular elements (12) are separated in the longitudinal direction by a distance and that the casing (8) surrounding the spaces is perforated (16) and / or consists of air-permeable material.