U.S. patent number 3,756,249 [Application Number 05/182,956] was granted by the patent office on 1973-09-04 for smokable article having internal air passageway.
This patent grant is currently assigned to Kimberly-Clark Corporation. Invention is credited to Russell J. Kulick, William A. Selke.
United States Patent |
3,756,249 |
Selke , et al. |
September 4, 1973 |
SMOKABLE ARTICLE HAVING INTERNAL AIR PASSAGEWAY
Abstract
A smokable article, such as a cigarette, in which the wrapper
surrounds both a mass of tobacco filler and a longitudinally
extending tube, the latter serving as a passageway for air during
smoking. The tube preferably extends for the full length of the
smokable article, but air flow through it is obstructed during the
initial burning of the article. The tube may be provided along its
length with two or more partial obstructions to air flow, the air
flow permitted by each obstruction being greater the farther it is
from the burning end of the article. Preferably, the tube is formed
of combustible material, such as reconstituted tobacco.
Inventors: |
Selke; William A. (Stockbridge,
MA), Kulick; Russell J. (Glasgow, SC) |
Assignee: |
Kimberly-Clark Corporation
(N/A)
|
Family
ID: |
22670786 |
Appl.
No.: |
05/182,956 |
Filed: |
September 23, 1971 |
Current U.S.
Class: |
131/336; 131/339;
131/364 |
Current CPC
Class: |
A24D
1/00 (20130101) |
Current International
Class: |
A24D
1/00 (20060101); A24d 001/00 (); A24f 013/04 () |
Field of
Search: |
;131/9,8R,8A,4B,15C |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
1,905,273 |
|
Aug 1970 |
|
DT |
|
687,136 |
|
May 1964 |
|
CA |
|
Primary Examiner: Michell; Robert W.
Assistant Examiner: Pitrelli; John F.
Claims
What is claimed is:
1. A smokable article comprising a wrapper surrounding both an
elongated mass of tobacco filler and a tube extending
longitudinally of the article, said tube being empty for at least a
portion of its length so that said empty portion serves as an
unobstructed flow passageway for air during smoking of the article,
and means spaced apart along the length of said tube for at least
partially obstructing air flow through said tube, each of said
obstructing means being formed to permit greater air flow than the
next preceding obstructing means closer to the end of the article
which is first burned when the article is smoked.
2. A smokable article as defined in claim 1 wherein said tube is
formed of reconstituted tobacco.
3. A smokable article as defined in claim 1 wherein each said
obstructing means is a dent in said tube at least partially closing
the tube interior in the vicinity of said dent.
4. A smokable article as defined in claim 1 wherein said
obstructing means is a cut-out in said tube between its ends, said
cut-out permitting tobacco filler to enter said tube in the region
of said cut-out.
5. A smokable article as defined in claim 1 wherein each of said
obstructing means is a dent in the side of said tube.
6. A smokable article as defined in claim 1 wherein said
obstructing means closest to the end of the article which is first
burned completely obstructs air flow through said tube during the
initial burning of the smokable article.
7. A smokable article as defined in claim 1 wherein said tube is
formed of combustible material.
Description
This invention relates to smokable articles, and more particularly
to such articles provided with means for diluting with air the
smoke reaching the person smoking the article.
The invention is believed to be most useful with respect to
cigarettes, and hence the following description refers to
cigarettes. However, this is not intended to limit the scope of the
invention which is applicable to smokable articles generally.
The tar delivered to the smoke by a cigarette increases puff by
puff as the cigarette is consumed. This arises from three separate
mechanisms, all operating in the same direction. The first relates
to the fact that air enters the cigarette, during each puff,
through the porous paper wrapper, thereby diluting the smoke and
reducing the tar reaching the smoker. As the cigarette grows
shorter, the dilution of the smoke by air is reduced since less of
the porous paper wrapper is available to provide dilution.
Secondly, the tobacco rod within the wrapper serves to some extent
as a filter for the smoke, and the length active in filtration is
diminished as the length of the cigarette decreases. Third, the tar
filtered by the tobacco during the earlier puffs adds to the
richness of tar generation when the last tobacco is finally
burned.
The fact that the tar "delivery profile" is uneven, i.e., tar
delivery being lowest during the first few puffs and highest during
the last few puffs, is unfortunate because tar delivery and
fullness of taste are somewhat related. Smokers trying a "low tar"
cigarette are most likely to judge the flavor critically during the
first puffs, and as mentioned above, these have the fewest tars and
hence are weakest in taste. On the other hand, the total tars
delivered in smoking the full length of the cigarette includes the
strong puffs near the butt.
Various suggestions have been made in the past for "leveling" the
tar delivery profile, but all involve disadvantages either from the
point of view of manufacturing cost or operability. For example,
ventilation holes have been provided at the cigarette filter to
provide a principal part of the dilution air, rather than relying
completely on air brought in through extremely porous paper. These
ventilation holes are a relatively more constant source of
dilution. Another approach appears in U.S. Pat. No. 3,526,904
wherein apertures in the cigarette wrapper are initially closed by
a water-soluble material. During smoking, the moisture in the
tobacco smoke dissolves the material and opens the aperture to
provide increased dilution.
It is an object of the present invention to provide a cigarette
having a more uniform tar delivery profile than conventional
cigarettes, and more specifically to provide a cigarette wherein
the ratio of tar delivered during the first few puffs to total tar
delivered by the complete cigarette is higher than in conventional
cigarettes.
It is another object of the invention to furnish a cigarette
construction by means of which the tar delivery profile can be
"programmed" by providing different amounts of air-dilution during
different stages as the cigarette is smoked.
It is a further object of the invention to provide such a cigarette
which delivers less total tar, when the entire cigarette is smoked,
than an otherwise identical conventional cigarette.
Additional objects and features of the invention will be apparent
from the following description in which reference is made to the
accompanying drawings.
In the drawings:
FIG. 1 is a longitudinal cross-sectional view of a cigarette made
according to the present invention;
FIG. 2 is a transverse cross-sectional view taken along line 2--2
of FIG. 1;
FIG. 3 is a longitudinal cross-sectional view through an
alternative form of air passageway tube; and
FIG. 4 is a longitudinal cross-sectional view through another
alternative form of air passageway tube.
The smokable article chosen to illustrate the present invention,
and shown in FIGS. 1 and 2, is a cigarette including a cylindrical
paper wrapper 10 surrounding an elongated mass or rod of tobacco
filler 11. A filter plug 12 engages one end of the wrapped tobacco
rod, and is surrounded by a cylindrical mouthpiece 13.
According to the invention, the cigarette is furnished within the
paper wrapper 10, and among the tobacco filler 11, with a small
tube 14 extending longitudinally of the cigarette. Tube 14 serves
as an internal air passageway within the cigarette. In the present
example, tube 14 extends for the full length of the tobacco rod 11,
and is made of combustible material. As a practical matter these
two characteristics are highly desirable, but neither absolutely
essential for proper functioning of the invention.
The end 15 of the cigarette is the one which is lit when the
cigarette is smoked. Spaced from end 15, but closer to that end
than to filter 12, tube 14 is deformed by a dent 16 in its side
wall which at least partially, but preferably completely, obstructs
the flow of air through the tube. When the cigarette is lit, and
during the first few puffs, little or no air flows through tube 14
to filter 12, i.e., to the smoker. Hence, the smoke is not diluted
by air flowing through tube 14, and the tar delivery is about the
same as that obtained with a conventional cigarette.
However, when the burning end of the cigarette reaches and burns
through dent 16, tube 14 is opened, and with each subsequent puff
air flows through tube 14 to dilute the smoke. Furthermore, as tube
14 becomes shorter with each puff, the resistance which it offers
to air flow diminishes. Consequently, tube 14 provides the greatest
air dilution during the last puffs of the cigarette when, as
mentioned above, tar delivery is greatest with a conventional
cigarette.
Tube 14 can be made of a variety of materials and in a variety of
ways. For example, the tube can be made of paper, or other sheet
material, wound in the manner of a small diameter drinking straw.
Alternatively, paper-like reconstituted tobacco, such as that
described in U.S. Pat. No. 3,145,717, can be used instead of paper.
Tube 14 can also be made of extruded plastic, or molded or extruded
compositions including clay or chalk bonded with starch. The tube
may also be formed of extruded reconstituted tobacco, as described
below in example II.
The amount of air dilution afforded by tube 14 depends primarily
upon its internal diameter. However, the material of the tube
should be given consideration. Tubes made of reconstituted tobacco
are preferred since their use keeps the amount of non-tobacco
material in the cigarette to a minimum. If tubes of paper or
plastic are used, there is necessary concern for possible acridity
or other less desirable combustion products, although the
particular paper used can minimize this problem. The tube material
chosen preferably burns at the same rate as tobacco, since a tube
which burns much more slowly, or not at all, would project out from
the partially consumed cigarette and be unsightly. On the other
hand, a tube which burns much faster than tobacco would tend to
become closed off at its burning end after each puff, thereby
greatly reducing the air drawn through the tube.
For manufacturing purposes, the tube should be one which can be
made in very long lengths, or better still, in long coils. In this
way, the tubular material can be fed directly into the cigarette
making machine and wrapped in the paper 10 together with the
tobacco. The formation of dent 16 can be accomplished by a roller
synchronized with the ultimate cutting of the continuous cigarette
rod into individual cigarettes, the roller operating on a portion
of the tube not forming part of a cigarette rod but which will be
used during the next cycle of the cigarette making machine.
In place of the dent 16, obstruction of air flow can be
accomplished by cutting out a portion, say one-half, of the
circumference of the tube so that when the cigarette is made, the
region of the tube at the cut-out is filled with tobacco, this
tobacco forming the obstruction to air flow. FIG. 4 illustrates a
tube 14" of this nature having a cut-out 17. If the cut edges of
cut-out 17 are rough, they may also help to obstruct air flow. Air
dilution is also reduced by virtue of the fact that some of the
smoke traveling along the tobacco rod 11 toward the smoker will
enter the tube through cut-out 17 and mix with the air therein. The
knife for producing the cut-out can be synchronized as described
above with respect to the denting roller.
Although for practical reasons, as mentioned above, tube 14 will in
most cases extend for the full length of tobacco filler 11, it
should be mentioned that the tube could be shorter. A tube
extending only from filter 12 to the location of dent 16, or some
other point along the length of the cigarette, would adequately
serve the purpose of the present invention.
An advantage of the present invention is that the amount of air
dilution provided as the cigarette is consumed can be caused to
follow a predetermined program. For example, as shown in FIG. 3,
tube 14' may be furnished not only with a dent 16' which closes the
tube completely, or obstructs its interior to a great extent, but
with additional dents 18 and 19 as well, spaced apart along the
length of tube 14'. In the example illustrated, dent 18 obstructs
air flow to a lesser extent than dent 16', and dent 19 obstructs
air flow to a lesser extent than dent 18; end 15' of tube 14' is
arranged at the end of the cigarette which is lit. As many dents as
desired may be provided, and each dent may obstruct air flow to a
lesser or greater extent than the dent preceding it.
The following examples will help to illustrate the advantages of
the present invention:
EXAMPLE I
A tube was prepared by spiral winding a sheet of reconstituted
tobacco, around a wire mandrel, resulting in a tube of 2.3
millimeters, inside diameter. This reconstituted tobacco had a
basis weight of 48 grams per square meter.
Cigarettes were made, 70 millimeters long, using conventional
cigarette filler tobacco blend. These cigarettes were of three
types, as follows:
A. A tube, open throughout its length, with 0.86 gram of tobacco
was wrapped in cigarette paper;
B. The cigarette was similar to that in A, above, except that
before assembly the tube was indented at a point 20 millimeters
from what was to be the lighting end of the cigarette;
C. As a control, a conventional cigarette was made with 1 gram of
tobacco and no tube was included.
These cigarettes were evaluated for tar delivery using a variation
of the accepted FTC procedure. The tar of the first three puffs of
each cigarette was collected on a separate filter and weighed
separately. The puffing was continued and at a time when no more
than four puffs remained, the tar delivery in the next three puffs
was determined, and this value was designated as the tar from the
"last three puffs." The tar of the last three puffs was collected
and its weight determined separately. The tar delivery of the total
cigarette was determined separately on additional cigarettes. The
results of these tests are given below:
Tar Delivery mg. First 3 Last 3 Complete Puffs Puffs Cigarette A.
Open Tube 3.9 4.2 14.3 B. Tube with Obstruction 5.9 tg 3.8 15.2 C.
Without Tube 6.2 10.2 29.1
EXAMPLE II
To prepare extruded tubes of reconstituted tobacco, a mixture was
prepared of 70 percent dry ground tobacco and 30 percent powdered
cellulose acetate. A solvent mixture of one part methanol and three
parts isopropanol was added with mixing to bring the mass to a
consistency of a stiff putty. Tubes were prepared by extruding this
mixture through a macaroni die with a laboratory press. After
drying, these tubes had an inside diameter of 2.1 millimeters.
Two types of cigarettes were prepared as follows:
A. A completely open tube was included in a cigarette made with
0.91 gram of filler tobacco;
B. Cigarettes were made as described above, except that prior to
the assembly of the cigarette, one-half of the circumference of the
tube was cut away at a point 20 millimeters from the end to be lit,
as shown in FIG. 4. The remainder of the tube was not collapsed by
this cutting. These cigarettes were evaluated in the same manner as
those in Example I, and the results are given below together with
the results obtained with the control cigarettes described in
Example I:
tar Delivery mg. First 3 Last 3 Complete Puffs Puffs Cigarette A.
Open Tube 4.6 5.5 18.2 B. Tube Opened 20 mm. from Edn 7.8 4.9 17.8
C. Without Tube 6.2 10.2 29.1
It will be seen from these examples that when a tube having an
obstruction is employed, the first few puffs deliver virtually the
same amount of tar as conventional cigarettes. However, the tar in
the last few puffs, and the total tar delivered by the cigarette is
greatly reduced. Furthermore, when the tube is unobstructed, little
or no "profiling" of tar delivery is achieved. It is only when the
tube is obstructed that tar delivery during the initial puffs is
virtually the same as that obtained with a conventional cigarette,
but tar delivery during the last puffs is greatly reduced as
compared to a conventional cigarette. In addition, it is clear that
use of the tube greatly reduces the total tar delivered by the
cigarette, only a part of the reduction being accounted for by the
fact that the tube-containing cigarette includes less tobacco than
the conventional cigarette.
The invention has been shown and described in preferred form only,
and by way of example, and many variations may be made in the
invention which will still be comprised within its spirit. It is
understood, therefore, that the invention is not limited to any
specific form or embodiment except insofar as such limitations are
included in the appended claims.
* * * * *