DE2361970A1 - FILTER ELEMENT FOR A SMOKING PRODUCT - Google Patents

Description

Filter element for a smoking product

The invention relates to a filter element 'for a smoking product' and in particular a filter for a smoking tobacco product *

In recent years there has been a tendency in the tobacco industry to use filter materials for smoking tobacco products, in particular cigarettes, with ever greater efficiencies. In this context, efficiency is defined as the amount of total particulate matter that is removed from the smoke produced by the burning tobacco before it reaches the smoker _{or the like}

Although the increased efficiency is often desirable, the first few puffs of a smoking tobacco product using such a high efficiency filter generally has no taste or effect to the smoker. On those first few puffs, it is not just the high-efficiency filter that has the effect, a considerable part of the to remove entire particulate matter, but the effect of the entire tobacco column becomes the effect of the filter

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added. Because of this combination becomes almost the entire particulate matter removed so / that the smoker from these receives no satisfaction for the first few moves.

Although not directed to the same problem, US Pat. No. 3,272,750 discloses 75 ° channels in a filter for a smoking tobacco product described. Various spatial arrangements and configurations are provided for the channel, with the channel runs over the entire length of the filter section. It follows that, however, with each of these spatial arrangements and configurations of the channel being closed by application of finger pressure before the cigarette is used. The filter element is specifically designed in such a way that to be compressible.

According to the present invention, one or more channels are on or in a filter element for a smoking tobacco product such as e.g. formed into a cigarette, the filter element being shaped or provided with a protection in such a way, around a. To prevent compression and the duct part in general during the entire smoking process of the product to leave open. While the beginning of the channel is in direct contact with the tobacco section of the smoking product, it ends Canal just before the end of the mouthpiece. At the end of the channel there is a small opening leading to the filter material.

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The filter element is designed to be generally resistant to compression so that the channel -for the entire time the smoke product was smoked can stay open

Because of the size of the channel and the orifice, due to the relationship to the efficiency of the filter element, flows into during the initial stages of smoking through at least a portion of the smoke generated by burning the tobacco product the channel and opening and then through a shortened portion of the filter element. The walls of the canal are with With the exception of the opening, it is essentially impervious to the smoke, so that no filtration takes place through these walls. In the course of the smoking process, the area of the filtration element in the vicinity of the opening is due to the accumulation of solid material gradually clogged · If this clogging continues, it increases Resistance to the smoke flowing through this shortened part of the filter, so that gradually increasing the all or substantially all of the smoke generated by the burning tobacco product passes directly through the main filter section will flow. In this way there is a general balance in the release of the particulate en total substance.

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Although a high-efficiency filter is used, because of the shortened path of the first, the trains a few puffs through the filter element a generally full taste. As is known, most of the time the first a few puffs of a cigarette definitely has a typically low total particulate matter content. In large part, this is due to the filtering effect of the tobacco column, so that in no case maximum filtration through the filter element is required.

The invention thus creates, so to speak, a programmed filter element for a smoking product with a tobacco section, comprising: a main filter element having a mouthpiece end that interfaces with the tobacco portion is arranged in alignment; at least one channel formed in the main filter element which is located on the tobacco section begins and the one just before the mouthpiece end of the main filter element ends with the walls of the duct being substantially impermeable to the flow of smoke; and at least an opening formed near the end of the channel.

In addition, the present invention provides a cigarette having a tobacco portion and a filter element created, in which the filter element is designed as described above, namely has the following parts:

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gin Hauptfiltrierelememt with a mouthpiece end which is arranged virtually aligned with the tobacco section, at least one channel formed in the Baiaptfiltrierelement, the open end in ύ & τ close to the tobacco portion .liegt ₉ wherein the channel terminates short of the mouth end of the Hauptfiltrierelementes and wherein the walls of the channel are essentially impenetrable to the flow of smoke, and at least one opening formed near the end of the duct ^

The invention will be described in the following as hand of exemplary embodiments with reference to the accompanying schematic Drawings explained in more detail5

Show it?

Figure% a perspective Jksis view of a preferred programmed filter according to the present invention with a single channel on the range $>

FIG. 2 shows a plan view of the filter element according to FIG. 1 in a smoking product?

FIG. 3 shows a plan view of a filter element according to the present invention with two channels, the channels having unequal lengths

FIG. K is a plan view of a filter element according to the present invention. a smoking tobacco product, the channels formed in the filter element being of equal length}

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FIG. 5 is a plan view of a filter element according to FIG present invention, wherein the channel formed on the periphery of the filter element is tapered J

FIG. 6 shows a plan view of a filter element according to FIG present invention in a smoking product, wherein the channel is external to the filter element;

FIG. 7 shows a plan view of a filter element according to FIG present invention in a smoking product, wherein the channel J is formed in the main part of the filter element and not along the circumference

FIG. 8 shows a section along line 8-8 of FIG. 7i

FIG. 9 shows a diagram in which, in milligrams, the particulate Total substance indicated is that for programmed and non-programmed filters are dispensed on a per puff basis I.

Figure Io shows a diagram with a representation of the efficiency - on a per puff basis - for programmed and non-programmed cigarette filters; and

FIG. 11 shows a representation of the discharged, particulate Total amount - on a per puff basis - to illustrate the effect of different opening sizes.

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1 of the accompanying drawings shows a filter element i according to the present invention. The filter element contains a filter material 2 with high efficiency, which is located in a casing 3 made of rigid plastic, in the. a channel or groove 4 is formed. An opening is located at the end of the channel or the groove 5. I ⁿ 2 is the filter element 1 shown in Fig.l shown in a cigarette eithält a tobacco section 6 and a cover sheet 7 which both the tobacco section 6 and surrounds the filter element 1 as an outer shell. In ^ ig. 2 it can be seen that the open end 8 of the channel k lies adjacent to the tobacco section, while no groove is provided at the found end 9 of the smoking tobacco product.

3 shows a filter element 11 in a smoking tobacco product with a tobacco section 16, both the filter element 11 and the tobacco section 16 being surrounded by a cover sheet 17 as a casing. The filter element 11 shown in Fig. 3 has a longer channel 12, with its open end 13 in the vicinity of the tobacco section 16 and an opening Ik at the end of the channel. Furthermore, in the filter element, a shorter channel 18 is formed, with the open end 19 is this K _ana i _s also in the vicinity of the tobacco portion; an opening 20 is formed at the closed end of the channel. Again, the channels end just before the mouthpiece end of the cigarette.

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i 8 -

In ^ ig. 4 is a filter element similar to the filter element 11 21 shown. The filter element is connected to a tobacco section 26 by a cover sheet 27. The two channels 22 and 22 'of the filter element 21 each have open parts 23 and 23 'of the channels in close proximity to the tobacco section, while the closed parts of the channels are formed with openings 24,24 are.

In Fig. 5 is again a filter element 31 with a tobacco section 36 connected, the two parts of a cover sheet 37 are sheathed. The filter element 31 includes a single channel 32, this channel differing from the channels described in the previous figures by its conical shape tapered shape differs, with the furthest part of the channel, the open end 33 near the tobacco section 36 is. The canal gradually tapers into a cone Direction towards the opening 3 ^ "the one at the closed end of the channel is formed. The channel ends again shortly before the mouthpiece end of the cigarette.

6 shows a filter element 41 with a filter material 42 of high efficiency. The filter material is adjacent to a tobacco section 46} the Fil'-trier material 42 and the tobacco section 46 are held together by a part 47 which is part of a cigarette holder can be. In the part 47 a channel 43 is formed,

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the part of the tobacco coupon closest to the Filter element 42 is located, with filter element 42 nearby, but does not connect at the mouthpiece end 44 of the smoking product,

In Fig. 7 ^e is illustrated in filter element 51 in combination with a tobacco section 56, wherein the two sections are covered by a common cover sheet 57 »A channel 52 is not formed in the filtering material 53 'sit high efficiency on the circumference of this material" The open end of the channel 54 is again in the vicinity of the Tabakab = section 5 ^ b and an opening 55 is formed in the closed end of the channel

It can be seen that the filter elements shown in each of the figures are not necessarily drawn to scale, but merely represent different embodiments that are possible within the concept of the present invention. Most of the channels have a length as shown, which is approximately 80 % of the total length of the filter element _o Usually the channel or channels should have lengths that make up 5 ° - 85 % of the length of the filter element Channels and the openings are generally shown larger than they would actually be formed in order to make the illustration clearer. The parameters for the different lengths and sizes will be given in detail below »

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In designing a useful filter of the type described here, several factors are of particular concern. Of the Overall efficiency of this type of filter is high Dimensions determined by the particular type of filter element selected for the main body of the filter. Also common Significant parameters include the length of the rod, the weight of the rod, the size and the fiber distribution. These

Parameters are also important here.

In the programmed filter of the present invention, additional important factors are the size of the opening at the end of the duct, the non-porous walls lining the duct, and the initial relationship between the resistance of the flow path for smoke through the duct and the opening compared to FIG the initial resistance through the main part of the filter element. Also of importance are the shape and spatial arrangement of the opening, the compression of the tow, the dimensions of the groove and the orientation of the fibers in the main filter element, in particular in the part of it which is in the vicinity of the opening.

The initial resistance ratio of the programmed filter is defined as the pressure drop of the main filter section, divided by the pressure drop of the shortened flow swe gs, the groove, the opening and the short section of the filter element contains. These values are obtained, independently, with an air flow of 15 cm / see.

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The percentages of the initial smoke puff flowing through the groove and opening are compared to the flow through the main filter section at different resistance ratios shown in Table 1 below

Table 1 Initial resistance ratio compared to smoke flow

Percent of the train volume

Main filter element 9Θ

67

5 © 25

17th

Regardless of the main filter element used, the programmed filter with the greatest resistance ratio will generally result in the lowest initial efficiency and the greatest increase in efficiency increase in later stages «Os preferred between. I ₉ O and 3 _f O "If the initial resistance ratio is below 0.5, there is no programming effect." Above a resistance ratio of S ₅ P, problems arise because once

relationship Groove opening 0.1 10 0.5 33 1.0 50 3.0 75 5.0 83

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the opening may be too large to be effectively blocked during the opening moves, or it may result in blockages that are broken on the later moves. In the preferred range of 1-3, the initial resistance through the groove opening in the short filter section is apparently equal to or less than the resistance through the main filter element. As a result, during the first puff, 50-75 % of the smoke passes through the groove opening with lower efficiency. When this path is gradually blocked, increasing proportions of the smoke pass through the _main filter section. In general, on the fourth or fifth puff, the resistance through the groove opening is greater than the resistance through the main filter element, so that most of the smoke is conducted through the main filter element. Normally, on the last puff, the opening is almost totally blocked so that practically all of the smoke is passed through the main filter element.

The effect of this programmed sequence can be seen from FIGS. 9 and 10. InjPig. 9 is the total delivery of particulate substance per puff both for a standard

a
Cellulose Acetate Filters / as well as programmed for one

Filter / illustrated according to the present invention. You can see that with the programmed filter, the per puff emitted Milligrams are essentially the same for the first and ninth puffs; in contrast, has turned

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With the usual cellulose acetate filter, the total release of particulate matter per puff in this pull area is more than doubled. The reason for this leveling of the tar delivery per puff can be seen in Fig. 10, in which the efficiency of the filter is shown for each puff. Here the efficiency of the standard cellulose acetate filter changes very little between the first and the ninth puff, while the efficiency of the programmed filter increases from approximately 40 % to 60 % during this same smoking period «,

If a single duct and opening is used, the optimal size of the opening formed at the end of the duct is between 12 and 30 Birmingham or stubs units. According to a preferred embodiment, the opening size for such a filter element is between 12 and 21 Birmingham or stub units. The channel leading to the hole should have a diameter of approximately 1-3 mm and generally be somewhat larger than the opening. Although the channel size is expressed as the diameter _s is the cross-sectional area of the channel and not its configuration or its diameter is the critical factor _o

The area of the channel should not be too large, otherwise there is a risk that the area of the main part of the filter material will be too smallj the channel represents part of the main filtration volume to be removed. The length of the

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Channel is not a critical size * it is selected in such a way that that the relative resistance between the main part of the filter material and the channel, the opening and the short Portion of the filtration material is within the ranges listed above.

A certain amount of impact is required to build up the particulate matter in that part of the filtering material which is near the opening at the end of the channel, to reach. The appropriate speed for this results from the appropriate design of the size, such as the Diameter, of the channel, as indicated above.

If more than one channel and opening are used, for example as shown in FIGS. 3 ^u * id k , then the total area of the plurality of openings should be somewhat larger than the area of a single opening in order to achieve the same result. Since the particulate matter collected around the opening in the filter material assumes a substantially hemispherical configuration, a larger amount of particulate matter is required to block an opening than a plurality of openings of the same area. Therefore, relative to the single opening, the size of the plurality of openings is increased so that substantially the same amount of particulate substance is required to block the plurality of openings as would be required for a single opening; through this

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the same type of programmed sequence is achieved. In the case of a multiplicity of openings, as shown for example in FIG. 3, in which the channels are not of the same length, a channel, for example channel 12, can be the channel through which the smoke flows during the first few puffs of the cigarette \ thereafter, the smoke flow can shift to a second channel, such as channel 18, and schließl-I, the fumes flow through the main part of the filtering material. Although only two channels are shown in FIG. 3, a different number of channels can of course also be used.

The effect of within the range noted above

15-19 stubs
varying opening size / is shown in Fig »II. The same filter element material is used here in each case '; In the diagram, the total release of particulate substance in milligrams per puff is plotted against the puff numbers, from 1 to 9. It can be seen that if the other factors are kept constant, a greater level of the release of particulate substance per puff is achieved as the opening size becomes smaller. Again, the leveling of the release of particulate matter in comparison with a control sample / can be determined »

If desired, the single channel of most of the illustrated embodiments, or one or more of the in Figs. 3 and 4 shown channels with a certain

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Material can be filled or partially filled to make a special one Achieve result. For example, an aromatic substance can be introduced into the duct to prevent the first puffs of smoke to give a special taste. If the canal contains such a material, then it should be of this type and Such a tightness has been used that the program effect of the filter is not lost.

The main filter element, for example 2 in FIG. 1, can be formed from different filter materials. It can consist of paper or cellulose acetate, for example. In general, it is selected for its filtration efficiency, and for a filter element according to the present invention, the particulate matter filtration efficiency should be at least about 50 % .

As shown in Fig. 1, the bulk of the filter material becomes surrounded by a plastic sleeve, the channel in this sleeve and the opening at the end of the channel through the sleeve are formed. The plastic sleeve has a dual function:

1 »It prevents the filter from being compressed, which would destroy the duct.

2. You maehV & the walls of the canal impenetrable, so that no filtration can take place through these walls.

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The plastic sleeve is not one of the critical features of the present invention as long as these two functions are fulfilled. For example, after the channel has been formed in the filter material, the periphery of the filter material can be coated in order to provide the necessary sealing and to increase the mechanical strength «Depending of the particular filter material used can also a heat seal has been used »

The effects of the various parameters mentioned above on the operation of the programmed filter are shown in the table shown. There the various parameters are given as well as the effect of increasing one of these parameters in Relation to the initial pressure drop of the filter, the initial efficiency of the filter, the initial flow rate through the channel and opening, the last pressure drop across the filter, and the last efficiency of the filter. An increase in any of these measured effects is as "+", a decrease as "-" and no change shown as "O".

In order to give the person skilled in the art a better possibility, the present To carry out the invention in practice, are in the following are some examples. However, these examples are intended as an illustration and not as a limitation the full scope of the present invention will be understood.

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Examples 1-3

In these examples, the filter element of cellulose acetate was - filters with 1.6 denier per fiber and 2k ooo denier formed per filter. They had an injected secondary curl. Three filters were formed from this material, each having opening sizes of 19t, 17 and 15 stubs units or diameters of 1.1, 1.5 and 1.8 mm, respectively. The total release of particulate matter in milligrams per cigarette, the initial pressure drops in inches of water column, the initial resistance ratios and the filter efficiencies are shown in Table 3. It can be seen that with each of these filters there was a substantial increase in the filter efficiency from the first to the last puff.

Example k

In this example, the cellulose acetate filter element was 1.6 deniers per fiber for a total of 48,000 deniers. The opening diameter was 1.8 mm, the stub unit was 15. The total particulate matter delivery was 12.2 milligrams per cigarette, and the initial pressure drop in inches of water was 3 »7 · The initial drag ratio was Q.9 · The cigarette exhibited an overall filter efficiency of 50 % which resulted in an initial efficiency of ^ k% and a final efficiency of 65 % .

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Example 5

In this example, a cellulose acetate filter element of 2.5 denier per fiber for a total of 44,000 denier was used. The opening sdur chine ss he was 1.8 tnm, so stubs unit. The total release of particulate matter for the cigarettes was 17.6 milligrams. The initial pressure drop was 2.2 inches of water and the initial drag ratio was 1.4. The cigarette showed an overall efficiency of 31 % with an initial efficiency of 16% and an end efficiency of 4? % contained.

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Tabel

Parameters increased

Initial filter pressure drop Initial Initial Final Pressure Efficiency Flow through drop in
of the filter channel and opening filter

Final effect s gra d of the filter

Opening size

CD CO CO CO CO

cn co cn

Canal area

Efficiency of the filter element

Distance of the opening from the suction end of the filter

NJ CO CD

Table 3

Hole diameter

Initial pressure drop

Initial

Resistance ratio

Stubs units inch water column

Filter efficiency in percent

all in all

Beginning

end

FY CF5

3.6 3.0 2.6

1.7.

2.2

58 47

38 3 ** 33

71 65 61

Claims (15)

1. Filter element for a smoking product with a tobacco section, a main filter element having a mouthpiece end that is substantially flush with the tobacco portion is arranged in alignment, and at least one channel formed in the main filter element, the channel on the tobacco section begins characterized in that the channel (4, 12, 22, 22 ', 32, 43) is just before the end of the mouthpiece (9.44) of the main filter element (1,11,21,31,41,51) ends; that the walls of the channel (4,12,22,22 ', 32,43,52) are substantially impervious to the flow of smoke; and that at least one opening (5,14,20,24,24 «, 34,55) near the end of the canal (4, 12, 22, 22 », 32, 43, 52) is trained. 2. Filter element according to claim 1, characterized in that that the channel (4,12,22,22 ») on the circumference of the main filter element (1,11,21) is formed. 3. Filter element according to claim 1, characterized in that that the channel (4,12,22,22 ', 32,43,52) axially in the A09836 / 0695 Main filter element (1,11,21,31,41,51) is formed. 4. Filter element according to one of claims 1 or 2, characterized in that that a single channel (4,32,43,52) is formed in the main filter element (1,31,41,51). 5. Filter element according to one of claims 1 or 2, characterized in that that several channels (12, 18; 22, 22 ') are provided, each of which has at least one opening (14, 20; 24, 24') in is assigned to the vicinity of its end «, 6. Filter element according to claim 5 * characterized in that that two channels (12.18; 22.22 ") are formed. 7. Filter element according to one of claims 5 or 6, characterized in that that each of the channels (22,22 ») has the same length, 8. Filter element according to one of claims 5 or 6, characterized in _s Λ 09836/0691 that the channels (12,18) have different lengths. 9. Filter element according to one of the preceding claims, characterized in that the width of the channel (32) is in the vicinity of the tobacco section (36) is larger than near its end. 10. Filter element according to one of the preceding claims, characterized in that that the circumference of the main filter element (1,11,21,31, 41,51) is wrapped in a plastic jacket (3). 11. Filter element according to one of the preceding claims, characterized in that that the opening size is between 12 and 30 stubs units. 12. Filter element according to claim 11, characterized, that the opening size is between 12 and 21 stubs units lies. 409836/0695 13. Filter element according to claim 1, characterized in that that the channel (43) is outside the main filter material (42) lies. 14. smoking product, characterized, that there is a filter element (1,11,21,31 _f 41,51) according to a which includes claims 1 to 13. 15. cigarette with a tobacco section and a filter element, characterized?
that the filter element is designed according to one of claims 1 to 13. Patent attorney ι ¹ C 409 836/0695 Blank page