Note: Descriptions are shown in the official language in which they were submitted.
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SMOKING ARTICLE
FIELD OF THE INVENTION
=
The invention relates to a smoking article and to
a method for preparing a smoking article.
BACKGROUND OF THE INVENTION
It is very hard for a smoker to give up smok-
ing entirely due to the addictive nature of nicotine
in the tobacco. An acceptable alternative has been to
arrange the nicotine in some other form or some other
way instead of smoking.
Known articles used to replace cigarettes
and/or to assist in giving up smoking include chewing
gums, plasters, nasal sprays or lozenges with added
nicotine.
A problem with these articles is that their
use does not provide a smoking experience. Smokers
want to have the actual smoking experience, whereby
they want e.g. to feel the taste of tobacco and smoke
in their mouth.
Patent publication US 7290549 discloses a
smokeless smoking article. The smoking article con-
tains tobacco and a smokeless chemical heat source
that heats and volatilizes the tobacco providing the
tobacco aroma or a tobacco-aromized aerosol. The heat
chamber of the heat source comprises a heat cartridge
which contains a chemical compound (such as magnesium
and iron) capable of producing heat, and an activating
solution (such as a solution of potassium chloride and
nitrate) separated by a frangible partition. In the
article, the heat producing reaction is provided by
combining the heat cartridge and the activating solu-
tion by breaking the partition.
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A problem with the smokeless smoking article is the slow rising
of the temperature to the optimum volatilization temperature region
of tobacco, which is about 125 to 1500C. In addition, the smoking
article requires that two separate chambers be combined to start the
heat producing reaction.
Patent publication EP 0371285 discloses a smoking article
comprising tobacco, a filter element and a heat source. The heat
source contains material (e.g. metal oxides and anhydrous metal
sulfates) which is capable of exotheimic reaction when contacted
with water. The contact between water and the components of the heat
source foIms heat which warms and volatilizes the tobacco. The water
required in the reaction may be injected into the heat source, it
may be incorporated in a separate rupturable capsule or it can be
incorporated in a solid salt, a salt hydrate.
Patent publication US 5285798 discloses a smoking article
comprising tobacco, a filter element and a heat source. The chemical
agents of the heat source, which comprise at least two metallic
agents, interact electrochemically when contacted with an
electrolyte solution, e.g. water. The electrochemical interaction
produces heat which walms and volatilizes the tobacco.
A problem with the above-mentioned smoking articles is that the
water which provides the exothermic reaction must be separated from
the co-reacting compounds in the smoking articles. These smoking
articles always require a separate water capsule, water injection or
release of water from a hydrous salt to provide the exothermic heat
producing reaction.
A new type of smokeless smoking article, which is sim-
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ple in structure and operation, and wherein the heat source quickly
reaches the temperature of the optimum volatilization region of
tobacco without a separate addition or chamber of liquid/water is
desirable. It is desirable to provide a smoking experience to the
smoker without combusting tobacco or other ingredients, without
outside smoke and without generating any combustion products, such
as carbon monoxide. It is desirable to alleviate the problems
referred to above.
It is desirable to provide a method for producing the smoking
article.
SUMMARY OF THE INVENTION
Disclosed herein is a smoking article comprising: tobacco; a
suction resistance; and a chemical heat source in conjunction with
the tobacco, wherein the chemical heat source comprises a heat
chamber formed by one continuous volume and the chemical heat
source is activated by external heat and/or oxygen excitation.
Disclosed herein is also a method for producing a smoking
article. The method comprises: forming the heat chamber by
combining the chemical compounds and enclosing them inside the heat
chamber, contacting a layer of tobacco with the heat chamber;
disposing the suction resistance at one end of the smoking article;
and coating the heat chamber contacted with the layer of tobacco.
The method further comprises fixing the chemical compounds onto a
planar structure; rolling the structure to form a tubular structure;
and disposing the tobacco inside or outside the tubular structure.
The smoking article according to the invention comprises
tobacco, suction resistance and a chemical heat source in
conjunction with the tobacco. The chemical heat source comprises a
heat chamber formed from one continuous volume and is activated by
external thermal and/or oxygen excitation. The chemical heat source
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is based on exothermic reaction.
The heat chamber may be closed.
The heat which is forming in the heat chamber reaches the
preferred volatilization region of 125 to 1500 C of tobacco quickly
and keeps the temperature in this region. The heat volatilizes the
aroma and nicotine from the tobacco. The tobacco aroma and other
active agents, such as nicotine, can be best released.
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without combustion or production of smoke in the pre-
ferred volatilization region.
The heat chamber contains chemical compounds
which are capable of producing heat. The chemical com-
pounds normally include a metal/metals and/or a strong
oxygen-containing oxidizer. The metal may be a transi-
tion metal, alkali metal, alkali earth and/or a metal
of some other group. Examples of typical applicable
metals include iron (Fe), aluminum (Al), magnesium
(Mg), lithium (Li), cobalt (Co), platinum (Pt), palla-
dium (Pd), copper (Cu), silicon (Si), preferably iron.
The strong oxygen-containing oxidizer may be a metal
oxide, metal peroxide and/or metal oxide salt, for ex-
ample potassium permanganate, manganese dioxide, lead-
3-tetraoxide, barium peroxide, bromates, chlorates
etc. The strong oxygen-containing oxidizer is prefera-
bly potassium permanganate (KMn04) or oxygen.
The chemical compounds are selected so as to
produce a safe reaction and so that the temperature
produced by the reaction rises quickly to the maximum
temperature which is not too high, and so that the
heat production in the reaction lasts for a long time.
In a preferred embodiment of the invention
the chemical compounds are anhydrous.
The heat chamber may also contain a reaction
catalyzing agent, for example carbon.
It is also possible to add inert filler mate-
rial in conjunction with the chemical starting com-
pounds in the heat chamber. The inert filler material
may also contain typical additives, such as binder,
which may for example accumulate heat.
The heat chamber is made from a material
which holds the temperatures generated by the heat
chamber reaction, and typically temperatures of about
220 C. Polymer-, paper-, natural fiber -, ceramic-,
glass- and/or metal-based materials, which stand the
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temperature and pressure generated in the reaction and
the compounds formed in the reaction, can be used for
making the heat chamber. The polymer-based materials
may include polypropylene, polyethylene, other poly-
5 olefins, polyesters and/or other equivalent polymeric
materials and/or mixtures thereof. The
paper-based
material may include paper and/or coated paper and/or
other material based on natural fibers.
The material of the heat chamber is imperme-
able to oxygen when oxygen is used as the oxidizer.
The heat chamber may be provided with a heat
insulating and/or heat accumulating layer. The heat
chamber is preferably provided with an insulating
layer when it is made from heat-conducting material,
such as for example aluminum. The insulating layer may
be made from natural or synthetic polymeric material,
such as textile, paperboard or polystyrene or from ce-
ramic, glass- or metal-based material. The heat accu-
mulating layer enables to obtain steady and longer-
lasting optimum heat. The heat accumulating layer may
be made for example from wax.
The external excitation which activates the
heat source is heat and/or oxygen. The heat is pro-
vided by fire for example using a match or a lighter,
by electricity using for example an electrically
heated resistance wire, by a detonator and/or other
starting heat providing excitation. The applied oxy-
gen may normally be oxygen contained in the air con-
tacted with the heat source for example by breaking
the wall of the airtight heat chamber which is imper-
meable to oxygen, by removing, in a smoking article
covered by a protective film/package that is imperme-
able to oxygen, this film/package, and/or by contact-
ing the heat chamber which is impermeable to oxygen
with air in an equivalent manner.
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In one preferred embodiment of the invention,
the heat source contains iron and potassium permanga-
nate as the chemical compounds. Reaction between the
staring materials is initiated by introducing starting
heat to the mixture by a match, lighter, detonator
and/or resistance wire. Oxygen is not required in
starting the reaction.
Reaction rate and heat produced in the reac-
tion can be adjusted by weight ratios of the chemical
compounds. The weight ratio is also selected according
to thermal conductivity of the coating material in the
heat chamber.
In one preferred embodiment of the invention,
the weight ratio between potassium permanganate and
iron ranges from 5/95 to 95/5, preferably from 25/75
to 50/50 and is more preferably 30/70.
In a further preferred embodiment of the in-
vention, the heat chamber contains iron, sodium sul-
fide and carbon, which are contacted with each other
in the presence of oxygen or air according to the fol-
lowing reaction:
Na2S x H20 + C + Fe + Ca0 + 02 --,
Na2SO4 + CaCO3 + Fen0m (iron oxides)
By the catalyzing effect of carbon, iron
heats up and raises further the heat produced in the
reaction. The sodium sulfide may be hydrous or anhy-
drous. Calcium oxide reacts with the sodium suplhide
crystal water and temperature produced in the reaction
raises more quickly. Material of the heat chamber is
impermeable to oxygen.
The tobacco may include one type of tobacco
and/or a mixture of tobacco, which may have been proc-
essed by the raw tobacco processing methods known in
the tobacco industry. The tobacco and/or the mixture
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thereof may include tobacco which has been processed
in many different ways, such as tobacco fine cut, to-
bacco strands, tobacco flakes, tobacco dust, processed
tobacco, extruded tobacco, reconstructed tobacco, to-
bacco extracts and equivalent processed forms of to-
bacco used in the tobacco industry. Tobacco extracts
include for example tobacco essences, aromatic oils of
tobacco, spray-dried and freeze-dried tobacco extracts
and the corresponding tobacco extracts used in prepar-
ing the tobacco raw material.
Also flavoring agents, such as menthol, va-
nillin, cocoa, licorice, cinnamic aldehyde and the
like, as well as tobacco aroma modifiers and other
modifiers, additives and fillers used in producing to-
bacco, and nicotine may be added to the tobacco.
The amount of nicotine included in the to-
bacco of the smoking article is typically 0.1 to
1.0mg.
Suction resistance of the smoking article
provides resistance when drawing on the cigarette, and
the smoker is, in this manner, able to use the sucking
rhythm to control his or her smoking rhythm. Suction
resistance is preferably disposed at one end of the
smoking article.
In a preferred embodiment of the invention,
suction resistance is a filter which prevents the to-
bacco from being contacted with the smoker and/or fil-
ters any harmful products which are formed during
volatilization of the tobacco, such as tar.
The smoking article may further comprise a
heat-providing element in conjunction with the heat
source used to activate the heat source. The heat-
providing element may be a detonator whereby the heat
chamber is activated for example by snapping the smok-
ing article, or a resistance wire, for example wolf-
ram, which heats up intensely when current is being
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conducted to the wire, a fuse and/or a firing tape to
introduce the starting heat to the heat chamber.
The smoking article may further comprise a
cooling part which cools down the fume drawn in and
breathed by the user and formed by volatilization of
the tobacco. The cooling part also enables one to ad-
just the amount of fume deriving from the fine cut to-
bacco. The flow section of the cooling part is equal
or substantially smaller than the flow section of the
smoking article. Adjusting the cross-section of the
cooling part to be smaller than the cross-section of
the smoking article reduces the amount of fume to be
drawn in and extends the time of use of the smoking
article. The cooling part is preferably disposed be-
tween suction resistance and the tobacco.
Material of the cooling part includes any
heat insulating and resistant material, preferably
heat resistant plastic.
In one embodiment of the invention, the heat
chamber is surrounded by the tobacco in the smoking
article. The heat chamber may be a bar- or spiral-
shaped, accordion-shaped or waved structure or one
which has been folded in any other form. By shaping
the structure of the heat chamber to the above-
mentioned form it is possible to fit a longer heat
chamber in the smoking article. A longer heat chamber
provides steadier and longer lasting optimum heat and
longer time of use for the smoking article.
In a further embodiment of the invention, the
tobacco is surrounded by the heat chamber in the smok-
ing article. The heat chamber is tubular.
The smoking article may be coated with to-
bacco paper and/or other material which is similar to
tobacco paper.
Surface of the tobacco paper may be treated
with a colorant, such as thermochrome pigment which
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changes color by the effect of heat. This makes the
cigarette look like burning.
The smoking article may be in the form of a
substantially tubular/bar-shaped object of a substan-
tially round cross-section. The cross-section may also
be angular or flattened. The smoking article is pref-
erably in the form of a traditional cigarette.
The smoking article is produced by
forming the heat chamber by combining the
chemical compounds and enclosing them inside the heat
chamber,
contacting a layer of tobacco with the heat
chamber,
disposing suction resistance at one end of
the smoking article, and
coating the heat chamber contacted with the
layer of tobacco.
The heat chamber may be formed as a structure
which is either substantially bar-shaped, spiral, ac-
cordion-shaped, waved or folded in any other form, or
as a tubular structure.
The layer of tobacco can be disposed to sur-
round the heat chamber which is substantially bar-
shaped, spiral, accordion-shaped, waved or folded in
any other form, or inside the substantially tubular
heat chamber.
Where required, a heat insulating and/or ac-
cumulating layer is disposed between the heat chamber
and the tobacco.
An insulating layer may be disposed, if nec-
essary, onto the layer of tobacco or the heat chamber
before coating or in conjunction with the coating. The
smoking article is typically coated with tobacco pa-
per.
If desired, a cooling part may be disposed at
one end of the smoking article. The cooling part is
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preferably disposed between suction resistance and the
tobacco.
The smoking article according to the inven-
tion wherein the tobacco is surrounded by the heat
5 chamber can also be produced by gluing/fixing the re-
action starting materials, the chemical compounds, on
a planar structure which is rolled to form a tubular
structure. A protective film, insulator and/or accumu-
lating layer may be disposed onto the starting materi-
10 als for example by lamination. The tobacco is disposed
inside or outside the tubular structure. The planar
structure may be formed by tobacco paper, an insulat-
ing layer and/or heat-accumulating layer.
Production of the heat source requires a sub-
stantially oxygen-free atmosphere including for exam-
ple nitrogen, carbon dioxide or argon gas when oxygen
is used as the external heat source excitation. The
production is carried out as a batch process. In this
case, the chemical compounds are mixed and the heat
chamber seamed in an entirely closed oxygen-free space
filled with nitrogen or argon gas. Airtightness should
be maintained from production to the user. The smoking
article may be packed in an airtight individual pack.
The smoking article according to the inven-
tion is immediately ready to use when the smoker acti-
vates the exothermic heat chamber reaction by the
starting heat or oxygen. The temperature of the heat
chamber quickly rises to the volatilization tempera-
ture of tobacco and volatilizes nicotine and aromas of
the tobacco and/or flavoring agents added to the to-
bacco. The smoker is able to sense the volatilized
nicotine and aromas of the tobacco and have the smok-
ing experience without smoke when drawing in tobacco
through the filter. The heat chamber produces heat
sufficiently and quickly to volatilize the components
of the tobacco while maintaining the temperature in
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the preferred volatilization region for minutes. The
smoking article and its heat chamber are simple is
structure and operation. No combining of chemical com-
pounds with water for example by injecting water into
the heat chamber, breaking a separate liquid capsule
or using hydrous salts is required in the production
of energy in the heat chamber. When handled, the smok-
ing article feels the same as a real smoking article,
such as a cigarette or cigar, and has the same visual
appearance. In addition, the smoking article has good
storage endurance. Reaction products of the smoking
article are not toxic and can be safely disposed of
with normal household waste.
LIST OF FIGURES
Fig. 1 shows a smoking article according to
the invention as seen from the side,
Fig. 2 shows a second smoking article accord-
ing to the invention as seen from the side,
Fig. 3 shows a third smoking article accord-
ing to the invention as seen from the side,
Fig. 4 shows a cross-section of the smoking
article according to the invention,
Fig. 5 the effect of the chemical compounds
in the heat chamber and their weight ratio on the hea-
ting rate, maximum temperature and temperature changes
in time.
Fig. 6 shows a fourth smoking article accord-
ing to the invention as seen from the side,
Fig. 7 shows a fifth smoking article accord-
ing to the invention as seen from the side, and
Fig. 8 shows a sixth smoking article accord-
ing to the invention as seen from the side.
DETAILED DESCRIPTION OF THE INVENTION
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The smoking article (1) according to Fig. 1
is formed as a cigarette. The smoking article com-
prises a substantially bar-shaped heat source (2),
which is a closed heat chamber surrounded by a layer
of tobacco (3). At one end of the smoking article
there is suction resistance (4) which is normally a
filter. The heat source (2) contains chemical com-
pounds which provide an exothermic reaction, prefera-
bly an oxidizable metal Fe and a strong oxygen-
containing oxidizer KMn04. The compounds of the heat
chamber may be present in an inert filler. The smoking
article (2) has been coated with tobacco paper (7).
In the smoking article (1) according to Fig.
2 tobacco (3) is surrounded by the bar-shaped closed
heat source (2). In other respects, the smoking arti-
cle is similar to that described above.
In the smoking article (1) of Fig. 3 and 4 a
heat accumulating layer (5) has been disposed between
the heat source (2) and the layer of tobacco (3), re-
leasing heat more steadily and maintaining the tem-
perature for a longer period of time in the desired
volatilization region of tobacco. The heat accumulat-
ing layer (5) is a layer that contains for example
metal, such as aluminum. Further, the layer of tobacco
(3) has been coated with a heat insulating layer (6),
for example a polystyrene-based material, which has
low ability of conducting heat, so that the cigarette
would not feel too hot in the hand.
Instead of the heat accumulating layer (5)
there may be disposed, in the position of the layer or
in conjunction with the layer, a heat insulating
layer, if the material of the heat chamber is heat
conductive and/or the reaction of the heat chamber
produces heat which exceeds the volatilization tern-
perature of tobacco.
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Alternatively, in the smoking article accord-
ing to Fig. 3 and 4, the heat source (2) may be dis-
posed in the position of the tobacco (3) and the to-
bacco (3) in the position of the heat source (2). In
this case, the tobacco is surrounded by the heat
source and the heat accumulating layer (5) is disposed
between them. In addition, the heat source is coated
by a heat insulating layer (6).
In the smoking article (1) according to Fig.
6 the bar-shaped heat source (2) has been bent to a
spiral form and the heat source is surrounded by the
tobacco (3). A longer heat chamber keeps the tempera-
ture longer in the desired volatilization region.
In the smoking article (1) according to Fig.
7 the bar-shaped heat source (2) has been folded in
accordion form and the heat source is surrounded by
the tobacco (3). Disposed between suction resistance
(4) at one end of the smoking article and the part
which forms the tobacco (3) and the heat chamber (2)
there is a cooling part (8) which is smaller in cross-
section than the smoking article and cools down the
fume that passes through it volatilizing from the to-
bacco, reducing the amount of fume drawn in and
thereby extending the time of use of the smoking arti-
cle. The cooling part (8) is normally made from heat
resistant plastic. The section (9) which surrounds the
cooling part (8) normally contains air.
The cross-section of the cooling part (8) may
also be equal to that of the smoking article, in which
case the cooling part merely cools down the fume that
volatilizes from the tobacco to be suitable for the
user.
In the smoking article (2) according to Fig.
8 the heat chamber (3) has been formed by combining
three bar-shaped heat chambers. A longer heat chamber
provides longer time of use.
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Example 1
The effect of the chemical compounds, start-
ing materials, of the heat chamber on the exothermic
reaction was tested in the experiments. Weight ratios
of different starting materials were used in the tests
to establish their effect on the heating rate, maximum
temperature and temperature changes in the course of
time. The heating tests were conducted with the reac-
tion of potassium permanganate and iron in weight ra-
tios of 30/70 and 70/30. A starting material mixture
of 1.0g was used in the tests. The reactions were con-
ducted by positioning the starting materials in alumi-
num or glass tubes, whereupon the reaction was actu-
ated by an electric fuse. The temperature was followed
by a thermoelement attached to the tube.
The tubes fitted inside the fine cut tobacco
part of a normal-size cigarette in such manner that
space was left for the fine cut tobacco. The internal
and external diameter and wall thickness of the alumi-
num and glass tubes were: Al 4.75mm, 4.05mm and
0.35mm: glass 5.06mm, 3.06mm and lmm. The tube length
was 55mm, which is suitable for a rolling machine with
filter.
The results of the conducted heating tests
are shown in Fig. 5.
The results indicate that in all tests the
temperature rose to the optimum volatilization region
of tobacco in less than 20 seconds.
The weight ratio of 70/30% Kmn04/Fe produced
clearly too high a temperature, in particular if one
intends to use paper as the wrapper. This weight ratio
requires the use of an insulating layer.
The weight ratio of 30/70% Kmn04/Fe was com-
pared in the glass tube, aluminum tube and insulated
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glass tube. According to the results, the glass tube
kept the heat longer than the aluminum tube and the
maximum temperature rose about 50 C higher.
Insulating the glass tube with an aluminum
5 foil covered by a thin fabric delayed the time of
reaching the maximum temperature for a few dozen sec-
onds. Reaching the volatilization region was delayed
by about 10s, but the temperature was maintained above
this region 2.5 times longer than with the non-
10 insulated tube, i.e. for about 2 minutes.
Example 2
The functionality of the smokeless smoking
15 article was tested in the experiment. Insulated glass
tube was used as the heat chamber structure. The
structure was similar to that of Example 1. The thick-
ness of the insulating layer formed by the aluminum
foil and the fabric was 0.56mm.
1.0g of a mixture of potassium permanganate
and iron (30/70) was introduced into the heat chamber.
The smoking article was produced by placing
the heat chamber into a rolling machine with tobacco
paper, filter and tobacco fine cut and by rolling the
smoking article.
Reaction starting heat was introduced to the
smoking article by a resistance wire which was heated
by conducting electric current to the wire.
After the test, the smoking article was exam-
ined visually and it was observed that tar had been
separated from the tobacco onto the paper surface.
From the filter it was visible that the heat chamber
reaction had separated ingredients from the fine cut
tobacco. There was no observed burning or blackening
of the fine cut tobacco in the cigarette when opened
after the test.
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The test proved that by the contrived heat
chamber composition and structure it is possible to
volatilize the tobacco aroma and nicotine from the to-
bacco in the smoking article.
Example 3
The test comprised analyzing the volatile
elements of the smokeless smoking article according to
the invention, a normal cigarette and a commercial
smokeless smoking article: nicotine, carbon monoxide
(CO) and tar. The smoking article according to Example
2 was used as the smokeless smoking article and Philip
Morris "Gold" Marlboro as the normal cigarette. A
smoking article according to Woodleaf Corporation
brand Aeros was used as the commercial smokeless ref-
erence smoking article, which is based on a plastic
tube that has been seamed at both ends and contains a
matrix including nicotine and tobacco aroma. The
smoker cuts off the ends of the plastic tube, and
nicotine and tobacco aroma are released into the mouth
and organs of the smoker when drawing in air through
the tube.
Nicotine and tar components were determined
by a GC-MS-apparatus and carbon dioxide by a GC-TDC-
apparatus. Two parallel assays were conducted for the
cigarettes. The results of the smoking article accord-
ing to the invention (SAI) have been scaled to the
amount of fine cut tobacco in a normal cigarette. The
results have been assembled in Table 1.
Table 1
SAI Marlboro Aeros
Nicotine (mg) 0.125 1.7 0.5 < 0.1
- indicated 0.6 0.05
Tar (mg) 9.4 0.3
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- indicated _8.0
Carbon monoxide 0.5 12.0 0.7 -
(mg)
- indicated 9.0
The invention is not limited merely to the
exemplary embodiments referred to above; instead, many
variations are possible within the scope of the inven-
tive idea defined by the claims.
_
