[0001] The present invention relates to tobacco smoke filters, especially for cigarettes.
[0002] Tobacco smoke filters can be manufactured from a number of different materials. The
majority of commercial cigarette filters are manufactured from cellulose acetate.
Other filtration media, such as paper, non-woven webs made from natural and/or synthetic
fibres, and other fibre tows (for example polypropylene), are used to only a limited
extent.
US 3 396 061 discloses a core of paper surrounded by a sheath of cellulose acetate tow with total
denier and filament denier within the ranges of claim 1.
[0003] Paper filters have a number of advantages over cellulose acetate, notably reduced
cost, higher particulate removal efficiency at equivalent pressure drop, higher adsorption
capacity for flavourings such as menthol, more rapid biodegradability, and less tendency
to collapse during smoking. However, paper filters have a number of disadvantages
compared to cellulose acetate, for example inferior end appearance and less acceptable
taste. The disadvantages mentioned above have prevented paper filters from gaining
widespread commercial usage.
[0004] A further limitation with paper filters is their reduced retention of toxic phenolic
compounds - for example phenol, cresols, catechol and resorcinol - found in volatile
and semi-volatile phases of cigarette smoke, compared to cellulose acetate filters;
this results in higher relative yields of phenolic compounds from cigarettes with
paper filters. This is caused by the well-known selectivity of cellulose acetate filters
towards phenolic compounds, rather than any inherent deficiency with paper filters.
However, it is, of course, still desirable to enhance phenol retention of paper filters
so a smoker would not be exposed to higher levels of phenolic compounds when smoking
a paper filtered cigarette compared to a cellulose acetate filtered cigarette.
[0005] According to the present invention in a first aspect there is provided a tobacco
smoke filter or filter element including (e.g. formed from) a coherent web comprising
(e.g. formed from materials including) a first filter material and a second filter
material and, optionally, one or more further filter materials; wherein the first
filter material comprises a cellulose acetate tow having a total denier of 44,000
or less and a filament denier of from 2.1 to 8.3 (for example 2.1 to 6.3 or 6.5 to
8.3, for example 2.1 to 6.3, for example from 3 to 6.2); and the second filter material
comprises a paper. The filter or filter element may be (or include) a rod including
(e.g. formed from) the coherent web.
[0006] The first filter material comprises a cellulose acetate tow and the second filter
material comprises a paper. As can be seen from Figure 3, the end appearance of filters
formed from a coherent web comprising these first and second filter materials has
a much enhanced and desirable end appearance, compared to a mono paper filter, because
the first filter material (cellulose acetate tow) fill in the small channels in the
paper folds that are normally associated with mono paper filters (see the prior art
mono paper filter illustrated in Figure 2). The filter or filter element of the invention
may provide the combination of satisfactory end appearance, efficient manufacture
and cost, and effective filtration.
[0007] The present Applicants have found that filter or filter elements of the invention
may also provide a remarkable selective filtration of phenolic compounds (e.g. phenol
and/or cresols) from cigarette smoke. It is well known that the tar retention of filters
and filter elements which include cellulose acetate and paper is proportional to the
ratio of cellulose acetate to paper in the filter, and it would be expected that the
retention of phenolic compounds would follow a similar trend. The Applicants have
found that use of a cellulose acetate tow with paper in a coherent web wherein the
cellulose acetate tow has specific characteristics (and/or wherein there are specific
amounts of cellulose acetate tow and paper) may provide unexpectedly high retention
of phenolic compounds, thereby resulting in lower deliveries of these toxic compounds
to the smoker.
[0008] The first filter material comprises a cellulose acetate tow which may be of continuous
filaments, as is well known in the art. Preferably, the first filter material comprises
a cellulose acetate tow having total denier from 11,000 to 40,000, preferably from
15,000 to 40,000, preferably from 16,000 to 39,000, preferably from 17,000 to 38,000,
preferably from 21,000 to 37,500. The first filter material may comprise a cellulose
acetate tow of filament denier from 3.1 to 4.9, for example from 3.5 to 4.8. The first
filter material may comprise a cellulose acetate tow of filament denier from 3.6 to
4.0, 4.5 to 4.9, 5.7 to 6.3, or 7.8 to 8.2.
[0009] In an example the first filter material comprises a cellulose acetate tow of filament
denier between 3.6 and 4.0 and, optionally, total denier between 25,000 and 39,000,
for example a cellulose acetate tow of filament denier 3.8 and, optionally, total
denier 37,000. In another example the first filter material includes a cellulose acetate
tow of filament denier from 4.5 to 4.9 and, optionally, total denier from 19,000 to
24,000, for example filament denier 4.7 and, optionally, total denier 22,000. In a
still further example the first filter material comprises a cellulose acetate tow
of filament denier from 5.8 to 6.2 and, optionally, total denier from 15,000 to 19,000,
for example a cellulose acetate tow of filament denier 6.0 and, optionally, total
denier 17,000. In a still further example the first filter material comprises a cellulose
acetate tow of filament denier from 7.8 to 8.2 and, optionally, total denier from
26,000 to 30,000, for example a cellulose acetate tow of filament denier 8.0 and,
optionally, total denier 28,000.
[0010] The second material comprises a paper. Preferably the second filter material comprises
a filtration paper, for example filtration paper to which a smoke modifying agent
(e.g. flavour) has been applied (see below). The second filter material may comprise
a paper (e.g. filtration paper) of basis weight from 20 to 40 g/m
2, for example from 32 to 40 g/m
2, for example 36 g/m
2.
[0011] The amount of first filter material in the coherent web may be from 20 to 80% by
weight, for example 25, 30, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,
49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 70, 75% by weight
of the coherent web. The amount of second filter material in the coherent web may
be from 20 to 80% by weight, for example 25, 30, 35, 36, 37, 38, 39, 40, 41, 42, 43,
44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64,
65, 70, 75% by weight of the coherent web.
[0012] The filter or filter element may include a further filter material. If present, the
further filter material may comprise, for example, a cellulose acetate tow (the same
or different to that of the first filter material), a paper, a non-woven web made
from a natural and/or a synthetic fibre, and/or other fibre tow, for example polypropylene.
The coherent web may include a web of first filter material and a web of second filter
material and a web of further filter material, wherein the first and further materials
are the same, and the second filter material is different (e.g the first and further
filter materials may be cellulose acetate, and the second material may be paper).
[0013] One (or more) of the first, second or further filter materials may include a smoke
modifying agent which, in use, becomes entrained in smoke passing through the filter
or filter element. The smoke modifying agent may be one which imparts an additional
taste or aroma to the smoke passing through the filter in use, or an agent which has
another effect (e.g. that of suppressing certain flavours or aromas). Examples of
flavour imparting agents include menthol, tobacco flavour, liquorice etc. The application
of smoke modifying agents e.g. flavours, is well-known, for example by direct injection
of flavour to filter tow prior to entry into the garniture during filter manufacture
or by applying a flavour solution to cotton thread that is subsequently entrained
in a filter. However, these and other methods have the disadvantage that only small
amounts of smoke modifying agent may be applied due to e.g. limited adsorption capacity
(of cellulose acetate) or limited quantity of material (in the case of cotton thread)
to which to apply the solution. Preferably the smoke modifying agent is included on
or in the second filter material which comprises paper, e.g. filtration paper, e.g.
a web of paper. Paper, e.g. filtration paper, is a naturally adsorbent material which
is available for the application of smoke modifying agent (e.g. flavour).
[0014] The filter or filter element may include granular additives such as activated carbon,
silica gels, zeolites, ion exchange resins or sepiolite. These granules may, for example,
be applied in a further step after production of the coherent web; may be included
in one or more of the filter materials (for example as carbon-impregnated paper);
or may be applied onto one (or more) of the filter materials prior to their facial
alignment and formation into a coherent web.
[0015] If granular materials are used, it may be desirable to use the combined material
filter as a segment of a dual, or other multi component, filter, as set out below.
[0016] The filter or filter element (e.g. the coherent web) may be over wrapped with a wrapper,
for example a wrapper of an air-permeable paper.
[0017] The tobacco smoke filter or filter element according to the invention may be of circumference
14 to 28 mm, for example 16 to 26 mm, for example 16 to 17 mm or 24 to 25 mm. A tobacco
smoke filter of the invention may be of length 10 to 40 mm, e.g. 15 to 35 mm, e.g.
20 to 30 mm. A tobacco smoke filter element of the invention may be of length 5 to
30mm, e.g. 6 to 20mm, e.g. 8 to 15 mm, e.g. 10 to 12 mm.
[0018] The present applicants have found that filter or filter elements of the invention
may have advantageous hardness characteristics. The definition of filter rod hardness
is known in the art (CORESTA Technology Group) and is defined as the compressed diameter
(DL) expressed as a percentage of the point of contact diameter (DP) when the filter
rod is subject to the following conditions (i) filter rods tested singly and initially
preloaded with a typically 10 g weight prior to the measurement of the point of diameter
(DP). Filter rods are then compressed under a static load of 300 grams in the form
of a flat disc of 12 mm diameter, the filter rod being supported by a flat surface
at least 15 mm long immediately opposite and parallel to the flat disc; (ii) the filter
rod must be located exactly on the centre line of the disc without restricting the
rod in the vicinity of the test area; (iii) the load is applied for 15 seconds, and
then the compressed diameter (DL) taken. The filter rod should be tested with the
lap joint (of the filter paper, if present) not directly in line with the applied
load, and preferably at 90° thereto. Filter rods should ideally be conditioned for
at least 48 hours at 22 ± 1°C and 60 ± 3% RH prior to testing and where possible the
tests should be carried out in an environment controlled to 22 ± 2°C and 60 ± 5% RH.
[0019] A tobacco smoke filter or filter element of the invention may have a hardness of
85% or above, preferably 90% or above as measured by the above defined test.
[0020] A filter element according to the invention may be used as a segment of a dual, triple,
or other multi component (multiple segment), filter. Dual and other multiple component
filters are known in the art. In an example, a dual, triple, or other multi component,
filter includes a granular additive(s) such as activated carbon, silica gels, zeolites,
ion exchange resins or sepiolite. It is preferred that the granular additive is not
included in the filter element of the invention (i.e. is included in one of the other
segments of the multi component filter). In an example the filter element of the invention
forms the mouth end segment of a dual segment filter, while tobacco end segment of
the dual filter includes a granular additive. It will be appreciated that a filter
element according to the invention which includes a granular additive (e.g. to which
a granular additive has been applied) may be used towards the tobacco end of a dual
or other multiple filter. In such instances, the mouth end filter element may be of
any construction that does not include a granular additive.
[0021] Filters according to the invention may be used in machine made cigarettes (e.g. those
mass produced and packaged). Filters according to the invention may also be used as
a filter tip for use with a individually rolled cigarette (e.g a hand rolled cigarette)
or a Roll Your Own or Make-your-own product.
[0022] According to the present invention in a further aspect, there is provided the use
of a coherent web comprising a first filter material and a second filter material
and, optionally, one or more further filter materials as, or in the production of,
a filter or filter element for selectively filtering phenolic compounds (e.g. phenols
and/or cresols) from smoke, for example tobacco smoke. The first filter material may
comprise a cellulose acetate tow having a total denier of 44,000 or less and a filament
denier of from 2.1 to 8.3 (for example 2.1 to 6.3 or 6.5 to 8.3, for example 2.1 to
6.3, for example from 3 to 6.2). The second filter material may comprise a paper,
eg., filtration paper.
[0023] The present invention also provides a method of production of a tobacco smoke filter
or filter element comprising aligning facially a web of a first filter material and
a web of second filter material (and, optionally, one or more further webs each comprising
a further filter material); and combining the facially aligned webs into a coherent
web; in which the first filter material comprises a cellulose acetate tow having a
total denier of 44,000 or less and a filament denier of from 2.1 to 8.3 (for example
2.1 to 6.3 or 6.5 to 8.3, for example 2.1 to 6.3, for example from 3 to 6.2); and
the second filter material comprises a paper. The webs of filter material may be combined
using, for example, a pair of rollers (e.g. nip rolls), the facially aligned webs
being passed (at e.g. the same linear speed) between the nip of the pair of rollers
under sufficient nip pressure to combine the webs. One or both of the rollers may
have a specific surface pattern thereon - e.g. embossed thereon. Passing the aligned
webs through the nip of the pair of rollers may add (e.g. emboss) a patterned surface
to the combined, coherent, web. The coherent web may then be passed into the garniture
arrangement of a conventional filter making machine for conversion into cigarette
filter rods. The applicants have found that forming a coherent web prior to passing
the filter material (e.g. the first and second filter materials) into the garniture
arrangement provides a uniform distribution of the plurality of filter materials (e.g.
the first and second filtration materials) across the cross section of the filter
or filter rod. It has been found that if the first and second (and further) filter
materials are simply passed into the garniture arrangement without being formed into
a coherent web there tends to be a non-uniform distribution of filter materials to
the detriment of the filtering characteristics of the product rod. The coherent web
may be formed by forming (e.g. compressing or sandwiching) the second filter material
(paper) between the first (cellulose acetate) and the further filter materials, or
by forming (e.g. compressing or sandwiching) the first filter material (cellulose
acetate) between the second (paper) and the further filter materials.
[0024] In a filter cigarette according to the invention, a filter of the invention (or a
filter which includes a filter element of the invention) is joined to a wrapped tobacco
rod with one end toward the tobacco. The filter may, for example, be joined to the
wrapped tobacco rod by ring tipping (which engages around just the adjacent ends of
a [wrapped] filter and rod to leave much of the filter wrapper exposed) or by a full
tipping overwrap (which engages around the full filter length and adjacent end of
the tobacco rod). Any filter or filter cigarette according to the invention may be
unventilated, or may be ventilated by methods well known in the art, e.g. by use of
a pre-perforated or air-permeable plugwrap, and/or laser perforation of plugwrap and
tipping overwrap.
[0025] According to the present invention in a further aspect, there is provided a filter
cigarette which includes a tobacco smoke filter or filter element according to the
invention.
[0026] The filters or filter elements according to the invention may be made (as discussed
above) as continuous rods. The continuous rod as it issues continuously from the production
machine outlet is cut into finite lengths for subsequent use. This cutting may be
into individual filters or filter elements as defined and described above, each of
which is then attached to an individual wrapped tobacco rod to form a filter cigarette.
More usually, however the continuously issuing rod is first cut into double or higher
multiple (usually quadruple or sextuple) lengths for subsequent use; when the initial
cut is into quadruple or higher lengths, then the latter are subsequently cut into
double lengths for the filter cigarette assembly - in which the double length filter
rod is assembled and joined (by ring tipping or full tipping overwrap) between a pair
of wrapped tobacco rods with the combination then being severed centrally to give
two individual filter cigarettes. The invention includes double and higher multiple
length filter rods (and/ or filter element rods).
[0027] The term denier is well known in the art, and expresses weight per unit length (linear
density) measure of a continuous filament or yarn. The term denier expresses weight
in grams of nine kilometers (9000 meters) length of the material. Therefore the lower
the denier number, the finer the material; the higher the denier number, the coarser
the material.
[0028] The present invention will now be illustrated with reference to the attached drawings
in which :
FIGURE 1 is a schematic side elevation view of an apparatus for forming filters according
to the invention;
FIGURE 2 is a photograph of the end of a conventional (i.e. prior art) mono paper
filter; and
FIGURE 3 is a photograph of the end of a filter or filter element according to the
present invention.
[0029] Figure 1 shows a schematic side elevation view of an apparatus for forming filters
or filter elements according to the invention. A band (1) of first filter material
is drawn from a bale (not shown) over a guide (2) into two sets of rollers (3, 3a
and 4, 4a). The first filter material comprises continuous cellulose acetate filaments
in the form of a 3.8Y37 cellulose acetate tow [expressed as filament denier/filament
shape/total denier (x1000), an expression well known in the art, so the 3.8Y37 tow
has Filament denier 3.8, a Y shaped cross section and a total denier of 37,000]. Such
a tow is well known. Rollers (4, 4a) rotate faster than rollers (3, 3a) causing the
tow to be stretched and opened to form a web of first filter material of width of
approximately 250 mm. The web of tow then passes into a spray booth (5) where it is
sprayed with glycerol triacetate before exiting the spray booth via a set of delivery
rollers (6, 6a). These operations are well known in the manufacture of cellulose acetate
filters. A web of second filter material in the form of a web of paper (7) with characteristics
suited for the manufacture of cigarette filters (a 90 mm width of a 36 g/m
2 paper supplied by Swiss Quality Paper) is unwound from a reel (8) and is fed into
the nip of a pair of nip rolls (9, 9a) at the same time, in the same linear direction,
and at the same speed, as the sprayed web of first filter material (tow). The web
of cellulose acetate tow (first filter material) and the web of filtering paper (second
filter material) are thus aligned facially (with one face of the web of cellulose
acetate tow facing one face of the web of filter paper) as they pass between the nip
of the pair of nip rollers (9, 9a). The nip rollers (9, 9a) have a specific grooved
pattern and are similar to those typically used to emboss filtration paper so that
it can be subsequently formed into a cylindrical rod (although the use of nip rolls
(9, 9a) in the processing of cellulose acetate filters is not normal) and are positioned
transversely or substantially transversely to the paths of the web of paper (7) and
the web of tow. The nip rolls (9, 9a) are at sufficient nip pressure to combine and
compress/emboss the web of filtering paper and the web of cellulose acetate tow into
a coherent web that then passes into the garniture arrangement of a conventional filter
making machine (not shown) for conversion into cigarette filter rods. A filter wrapper
of air permeable paper is applied around the filter rods by conventional means.
[0030] In one example of the invention, ("Sample B", see Example 1 and Table 1 below) the
apparatus of Figure 1 is used to produce filter rods (and filter tips) using 90 mm
width of a 36 gsm paper supplied by Swiss Quality Paper and a 3.8Y37 cellulose acetate
tow. The amount of cellulose acetate tow (first filter material) is 57% by weight
of the coherent web and the amount of paper (second filter material) is 43% by weight
of the coherent web. The resulting rod is cut into filter tips are of length 11 mm
(and circumference of around 25 mm). Samples A, C, D and E (Table 1) are made by a
similar method, using the first (cellulose acetate tow) and second (paper) filter
materials set out in Table 1.
[0031] In a further example of the invention, the apparatus of Figure 1 includes (not shown)
a means for imparting a flavouring agent (e.g. menthol) into the web paper (7). The
web of menthol flavoured paper (i.e. filter paper with menthol adsorbed thereon) is
included (with the web of cellulose acetate tow) in the coherent web, which is then
formed into filter rods. The resulting filters combine satisfactory end appearance
with ready and efficient adsorption of menthol into the body of the filter.
[0032] It will be appreciated by the skilled man how a further web or webs of further filter
material (e.g. further web of paper or tow) may be included (e.g. incorporated) into
the coherent web by aligning the further web(s) facially with the other webs as they
pass between the nip of the pair of nip rollers (9, 9a).
[0033] Figure 2 shows the end appearance of a mono paper filter of the prior art. It can
be seen that the end appearance is not satisfactory.
[0034] Figure 3 shows a photograph of the end appearance of a filter according to the present
invention, for example produced by the methods discussed with reference to Figure
1. It will be appreciated that the end appearance is greatly improved because the
cellulose acetate (first filter material) fill the small channels in the paper (second
filter material) folds. It will be appreciated that variation of the amounts of cellulose
acetate and paper will have some effect on the end appearance of the filters, although
the inclusion of cellulose acetate at an amount of greater than 20% by weight of the
filter should ensure an improved end appearance over a paper only filter, and effective
filtration. Filters according to the present invention, for example produced by the
methods discussed with reference to Figure 1, may advantageously have hardness of
85% or greater, for example 90% or greater, for example 95% or greater.
Example 1
[0035] A series of five sample filters (Samples A, B, C, D and E) of similar pressure drop
were made from cellulose acetate tow and paper to provide filters with a range of
cellulose acetate:paper ratios. This was achieved through the use of cellulose acetate
tows of different total deniers in combination with a 36 g/m
2 paper of different widths. Comparable control filters comprising 100% of the individual
materials were also manufactured. Table 1 lists the properties of these filters.
Table 1
Sample |
Tow Item1 |
Paper (36 g/m2) Width (mm) |
Acetate Content (%3) |
Paper Content (%3) |
Pressure Drop2 (mm WG) |
Acetate Control |
|
- |
100 |
0 |
|
A |
3.8Y37 |
65 |
63 |
37 |
358 |
B |
3.8Y37 |
90 |
57 |
43 |
320 |
C |
8Y28 |
95 |
54 |
46 |
296 |
D |
4.7Y22 |
120 |
45 |
55 |
291 |
E |
6Y17 |
150 |
34 |
66 |
363 |
Paper Control |
- |
|
0 |
100 |
|
1. expressed as Filament Denier/Filament Shape/Total Denier (x1000) an expression
well known in the art, so the 3.8Y37 tow has Filament denier 3.8, a Y shaped cross
section and a total denier of 37,000; 4.7Y22 tow has Filament denier 4.7, a Y shaped
cross section and a total denier of 22,000, and so on.
2. per 66mm filter rod
3. expressed as % (by weight) of the total weight of the coherent web, i.e. % by weight
of the total weight of acetate and paper in the sample filter. |
[0036] Cigarettes were constructed using these filters, smoked under ISO conditions and
their yields of tar, phenol and cresols measured. As expected, the tar yields from
filter cigarettes with higher contents of paper decreases as a consequence of the
higher filtration efficiency of paper as compared to cellulose acetate. Table 2 lists
the results obtained together with the expected and measured values of the ratio of
phenol:tar and cresols:tar. The quoted expected values are based on an anticipated
linear relationship between the values obtained from the acetate and paper controls.
It can be seen that the all five samples unexpectedly gave measured ratios lower than
expected. Filters A, B and C gave particularly selective filtration of phenol.
Table 2
Sample |
Tar Yield (mg/cig) |
Phenol Yield (µg/cig) |
Cresols Yield (µg/cig) |
Expected Ratio |
Measured Ratio |
Phenol: Tar |
Cresols: Tar |
Phenol: Tar |
Cresols: Tar |
Acetate |
16.7 |
25.5 |
21.3 |
1.53 |
1.28 |
1.53 |
1.28 |
A |
15.8 |
25.7 |
21.3 |
1.84 |
1.47 |
1.63 |
1.35 |
B |
15.7 |
25.3 |
20.8 |
1.89 |
1.50 |
1.61 |
1.32 |
C |
16.5 |
30.2 |
24.0 |
1.91 |
1.51 |
1.83 |
1.45 |
D |
16.5 |
28.7 |
23.0 |
1.99 |
1.56 |
1.74 |
1.39 |
E |
14.8 |
27.2 |
21.9 |
2.08 |
1.62 |
1.84 |
1.48 |
Paper |
13.9 |
32.9 |
24.9 |
2.37 |
1.79 |
2.37 |
1.79 |
1. A tobacco smoke filter or filter element including a coherent web comprising a first
filter material and a second filter material and, optionally, one or more further
filter materials; wherein the first filter material comprises a cellulose acetate
tow having a total denier of 44,000 or less and a filament denier of from 2.1 to 8.3
preferably 2.1 to 6.3 or 6.5 to 8.3; and the second filter material comprises a paper
having paper folds; wherein the cellulose acetate tow fills small channels in the
paper folds of said paper of the second filter material.
2. A tobacco smoke filter or filter element according to claim 1 wherein the first filter
material comprises a cellulose acetate tow having total denier from 11,000 to 40,000,
preferably when the first filter material comprises a cellulose acetate tow having
total denier from 21,000 to 37,500.
3. A tobacco smoke filter or filter element according to any preceding claim wherein
the first filter material comprises a cellulose acetate tow of filament denier from
2.1 to 6.3.
4. A tobacco smoke filter or filter element according to any preceding claim wherein
the second filter material comprises a filtration paper.
5. A tobacco smoke filter or filter element according to any preceding claim wherein
the second filtering material comprises a paper of basis weight from 20 to 40 g/m2.
6. A tobacco smoke filter or filter element according to any preceding claim wherein
the amount of first filter material in the coherent web is from 20 to 80% by weight
of the coherent web and/or wherein the amount of second filter material in the coherent
web is from 20 to 80% by weight of the coherent web.
7. A tobacco smoke filter or filter element according to any preceding claim wherein
one or more of the first, second or further filter materials includes a smoke modifying
agent, for example wherein the second filter material comprising paper includes the
smoke modifying agent.
8. A tobacco smoke filter or filter element according to any preceding claim further
comprising a granular additive; and/or further comprising a wrapper, preferably a
wrapper of an air-permeable paper.
9. A tobacco smoke filter or filter element according to any preceding claim having a
hardness of 85% or above.
10. A method of production of a tobacco smoke filter or filter element comprising aligning
facially a web of a first filter material and a web of second filter material and,
optionally, one or more further webs each comprising a further filter material; and
combining the facially aligned webs into a coherent web; in which the first filter
material comprises a cellulose acetate tow having a total denier of 44,000 or less
and a filament denier of from 2.1 to 8.3, preferably 2.1 to 6.3 or 6.5 to 8.3; and
the second filter material comprises a paper; and in which the cellulose acetate tow
fills small channels in the paper folds of the paper of the second filter material
in the coherent web.
11. A filter cigarette comprising a filter according to any of claims 1 to 9, or a filter
which includes a filter element according to any of claims 1 to 9, joined to a wrapped
tobacco rod with one end toward the tobacco.
12. A filter cigarette comprising a filter made by the method according to claim 10, or
a filter which includes a filter element made by the method according to claim 10,
joined to a wrapped tobacco rod with one end toward the tobacco.
13. A multiple length rod comprising a plurality of filters or filter elements according
to claims 1 to 9 joined end to end.
14. The use of a coherent web comprising a first filter material and a second filter material
and, optionally, one or more further filter materials, wherein the first filter material
fills small channels in the second filtering material comprising paper with paper
folds, as, or in the production of, a filter or filter element for selectively filtering
phenolic compounds from smoke, for example tobacco smoke.
15. The use according to claim 14 in which the first filter material comprises a cellulose
acetate tow having a total denier of 44,000 or less and a filament denier of from
2.1 to 8.3, preferably 2.1 to 6.3 or 6.5 to 8.3; and the second filter material comprises
a paper.
1. Filter oder Filterelement für Tabakrauch, der/das eine zusammenhängende Bahn enthält,
die ein erstes Filtermaterial und ein zweites Filtermaterial und optional ein oder
mehrere weitere Filtermaterialien umfasst; wobei das erste Filtermaterial einen Celluloseacetatfaserstrang
mit einem Gesamt-Denier von 44.000 oder weniger und einem Filament-Denier von 2,1
bis 8,3, vorzugsweise 2,1 bis 6,3 oder 6,5 bis 8,3, umfasst; und das zweite Filtermaterial
ein Papier mit Papierfalten umfasst; wobei der Celluloseacetatfaserstrang kleine Kanäle
in den Papierfalten des Papiers des zweiten Filtermaterials ausfüllt.
2. Filter oder Filterelement für Tabakrauch nach Anspruch 1, wobei das erste Filtermaterial
einen Celluloseacetatfaserstrang mit einem Gesamt-Denier von 11.000 bis 40.000 umfasst,
wobei das erste Filtermaterial vorzugsweise einen Celluloseacetatfaserstrang mit einem
Gesamt-Denier von 21.000 bis 37.500 umfasst.
3. Filter oder Filterelement für Tabakrauch nach einem vorangehenden Anspruch, wobei
das erste Filtermaterial einen Celluloseacetatfaserstrang mit einem Filament-Denier
von 2,1 bis 6,3 umfasst.
4. Filter oder Filterelement für Tabakrauch nach einem vorangehenden Anspruch, wobei
das zweite Filtermaterial ein Filterpapier umfasst.
5. Filter oder Filterelement für Tabakrauch nach einem vorangehenden Anspruch, wobei
das zweite Filtermaterial ein Papier mit einem Quadratmetergewicht von 20 bis 40 g/m2 umfasst.
6. Filter oder Filterelement für Tabakrauch nach einem vorangehenden Anspruch, wobei
die Menge an erstem Filtermaterial in der zusammenhängenden Bahn 20 bis 80 Gew.-%
der zusammenhängenden Bahn beträgt und/oder wobei die Menge an zweitem Filtermaterial
in der zusammenhängenden Bahn 20 bis 80 Gew.-% der zusammenhängenden Bahn beträgt.
7. Filter oder Filterelement für Tabakrauch nach einem vorangehenden Anspruch, wobei
eines oder mehrere des ersten, zweiten oder (der) weiteren Filtermaterials/-materialien
ein Rauchmodifizierungsmittel enthalten, beispielsweise wobei das Papier umfassende
zweite Filtermaterial das Rauchmodifizierungsmittel enthält.
8. Filter oder Filterelement für Tabakrauch nach einem vorangehenden Anspruch, der/das
ferner ein körniges Additiv umfasst; und/oder ferner eine Umhüllung, vorzugsweise
eine Umhüllung aus einem luftdurchlässigen Papier, umfasst.
9. Filter oder Filterelement für Tabakrauch nach einem vorangehenden Anspruch mit einer
Härte von 85 % oder darüber.
10. Verfahren zur Herstellung eines Filters oder Filterelements für Tabakrauch, umfassend:
flächiges Aufeinanderausrichten einer Bahn aus einem ersten Filtermaterial und einer
Bahn aus einem zweiten Filtermaterial und optional einer oder mehrerer weiterer Bahnen,
die jeweils ein weiteres Filtermaterial umfassen; und Kombinieren der flächig aufeinander
ausgerichteten Bahnen zu einer zusammenhängenden Bahn; wobei das erste Filtermaterial
einen Celluloseacetatfaserstrang mit einem Gesamt-Denier von 44.000 oder weniger und
einem Filament-Denier von 2,1 bis 8,3, vorzugsweise 2,1 bis 6,3 oder 6,5 bis 8,3,
umfasst; und das zweite Filtermaterial ein Papier umfasst; und wobei der Celluloseacetatfaserstrang
kleine Kanäle in den Papierfalten des Papiers des zweiten Filtermaterials in der zusammenhängenden
Bahn ausfüllt.
11. Filterzigarette, die einen Filter nach einem der Ansprüche 1 bis 9 oder einen Filter,
der ein Filterelement nach einem der Ansprüche 1 bis 9 enthält, verbunden mit einem
umhüllten Tabakstab mit einem Ende in Richtung des Tabaks, umfasst.
12. Filterzigarette, die einen mittels des Verfahrens nach Anspruch 10 hergestellten Filter
oder einen Filter, der ein mittels des Verfahrens nach Anspruch 10 hergestelltes Filterelement
enthält, verbunden mit einem umhüllten Tabakstab mit einem Ende in Richtung des Tabaks,
umfasst.
13. Mehrstückiger Stab, der mehrere endseitig verbundene Filter oder Filterelemente nach
den Ansprüchen 1 bis 9 umfasst.
14. Verwendung einer zusammenhängenden Bahn, die ein erstes Filtermaterial und ein zweites
Filtermaterial und optional ein oder mehrere weitere Filtermaterialien umfasst, wobei
das erste Filtermaterial kleine Kanäle in dem Papier mit Papierfalten umfassenden
zweiten Filtermaterial ausfüllt, als Filter oder Filterelement zum selektiven Herausfiltern
von Phenolverbindungen aus Rauch, beispielsweise Tabakrauch, oder bei der Herstellung
eines solchen.
15. Verwendung nach Anspruch 14, wobei das erste Filtermaterial einen Celluloseacetatfaserstrang
mit einem Gesamt-Denier von 44.000 oder weniger und einem Filament-Denier von 2,1
bis 8,3, vorzugsweise 2,1 bis 6,3 oder 6,5 bis 8,3, umfasst; und das zweite Filtermaterial
ein Papier umfasst.
1. Filtre ou élément filtrant à fumée de tabac comprenant une bande cohérente comprenant
un premier matériau filtrant et un second matériau filtrant et, éventuellement, un
ou plusieurs autres matériaux filtrants ; dans lequel le premier matériau filtrant
comprend une mèche d'acétate de cellulose présentant un denier total d'au plus 44
000 et un denier de filament de 2,1 à 8,3, de préférence de 2,1 à 6,3 ou de 6,5 à
8,3 ; et le second matériau filtrant comprend un papier comportant des plis de papier
; dans lequel la mèche d'acétate de cellulose remplit de petits canaux dans les plis
de papier dudit papier du second matériau filtrant.
2. Filtre ou élément filtrant à fumée de tabac selon la revendication 1, dans lequel
le premier matériau filtrant comprend une mèche d'acétate de cellulose présentant
un denier total de 11 000 à 40 000, de préférence lorsque le premier matériau filtrant
comprend une mèche d'acétate de cellulose présentant un denier total de 21 000 à 37
500.
3. Filtre ou élément filtrant à fumée de tabac selon l'une des revendications précédentes,
dans lequel le premier matériau filtrant comprend une mèche d'acétate de cellulose
de denier de filament de 2,1 à 6,3.
4. Filtre ou élément filtrant à fumée de tabac selon l'une des revendications précédentes,
dans lequel le second matériau filtrant comprend un papier filtrant.
5. Filtre ou élément filtrant à fumée de tabac selon l'une des revendications précédentes,
dans lequel le second matériau filtrant comprend un papier présentant un grammage
de 20 à 40 g/m2.
6. Filtre ou élément filtrant à fumée de tabac selon l'une des revendications précédentes,
dans lequel la quantité de premier matériau filtrant dans la bande cohérente est de
20 à 80 % en poids de la bande cohérente, et/ou dans lequel la quantité de second
matériau filtrant dans la bande cohérente est de 20 à 80 % en poids de la bande cohérente.
7. Filtre ou élément filtrant à fumée de tabac selon l'une des revendications précédentes,
dans lequel l'un ou plusieurs parmi le premier, le second ou les autres matériaux
filtrants comprennent un agent de modification de fumée, par exemple, dans lequel
le second matériau filtrant comprenant du papier comprend l'agent de modification
de fumée.
8. Filtre ou élément filtrant à fumée de tabac selon l'une des revendications précédentes,
comprenant en outre un additif granulaire ; et/ou comprenant en outre une enveloppe,
de préférence une enveloppe d'un papier perméable à l'air.
9. Filtre ou élément filtrant à fumée de tabac selon l'une des revendications précédentes,
présentant une dureté d'au moins 85 %.
10. Procédé de production d'un filtre ou d'un élément filtrant à fumée de tabac consistant
à aligner facialement une bande d'un premier matériau filtrant et une bande d'un second
matériau filtrant et, éventuellement, une ou plusieurs autres bandes comprenant chacune
un autre matériau filtrant ; et à combiner les bandes alignées facialement en une
bande cohérente ; dans lequel le premier matériau filtrant comprend une mèche d'acétate
de cellulose présentant un denier total d'au plus 44 000 et un denier de filament
de 2,1 à 8,3, de préférence de 2,1 à 6,3 ou de 6,5 à 8,3 ; et le second matériau filtrant
comprend un papier ; et dans lequel la mèche d'acétate de cellulose remplit de petits
canaux dans les plis de papier du papier du second matériau filtrant dans la bande
cohérente.
11. Cigarette à filtre comprenant un filtre selon l'une des revendications 1 à 9, ou un
filtre qui comprend un élément filtrant selon l'une des revendications 1 à 9, relié
à une tige de tabac enveloppée avec une extrémité orientée vers le tabac.
12. Cigarette à filtre comprenant un filtre fabriqué par le procédé selon la revendication
10, ou un filtre qui comprend un élément filtrant fabriqué par le procédé selon la
revendication 10, relié à une tige de tabac enveloppée avec une extrémité orientée
vers le tabac.
13. Tige à longueurs multiples comprenant une pluralité de filtres ou d'éléments filtrants
selon les revendications 1 à 9, reliés bout à bout.
14. Utilisation d'une bande cohérente comprenant un premier matériau filtrant et un second
matériau filtrant et, éventuellement, un ou plusieurs autres matériaux filtrants,
dans laquelle le premier matériau filtrant remplit de petits canaux dans le second
matériau filtrant comprenant du papier présentant des plis de papier, comme ou dans
la production d'un filtre ou d'un élément filtrant permettant de filtrer sélectivement
des composés phénoliques de la fumée, par exemple de la fumée de tabac.
15. Utilisation selon la revendication 14, dans laquelle le premier matériau filtrant
comprend une mèche d'acétate de cellulose présentant un denier total d'au plus 44
000 et un denier de filament de 2,1 à 8,3, de préférence de 2,1 à 6,3 ou de 6,5 à
8,3 ; et le second matériau filtrant comprend un papier.