U.S. patent application number 14/484813 was filed with the patent office on 2016-03-17 for tobacco-derived filter element.
The applicant listed for this patent is R.J. REYNOLDS TOBACCO COMPANY. Invention is credited to Evon L. Crooks.
Application Number | 20160073686 14/484813 |
Document ID | / |
Family ID | 54238548 |
Filed Date | 2016-03-17 |
United States Patent
Application |
20160073686 |
Kind Code |
A1 |
Crooks; Evon L. |
March 17, 2016 |
TOBACCO-DERIVED FILTER ELEMENT
Abstract
A filter material adapted for use as a filter element of a
smoking article is provided, the filter material including at least
10 dry weight percent of cellulosic pulp derived from stalks,
roots, or a combination thereof of a plant of the Nicotiana
species, wherein the filter material is in the form of a paper
comprising the cellulosic pulp or a fibrous tow comprising the
cellulosic pulp in esterified form. Filter elements and smoking
articles, such as cigarettes, that contain the filter material are
also provided. Methods of preparing filter materials for use in
filter elements are also provided.
Inventors: |
Crooks; Evon L.;
(Mocksville, NC) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
R.J. REYNOLDS TOBACCO COMPANY |
Winston-Salem |
NC |
US |
|
|
Family ID: |
54238548 |
Appl. No.: |
14/484813 |
Filed: |
September 12, 2014 |
Current U.S.
Class: |
131/331 ;
493/39 |
Current CPC
Class: |
A24D 3/0204 20130101;
A24D 3/0241 20130101; A24D 3/062 20130101; A24D 3/068 20130101;
A24D 3/10 20130101 |
International
Class: |
A24D 3/06 20060101
A24D003/06; A24D 3/02 20060101 A24D003/02 |
Claims
1. A filter material adapted for use as a filter element of a
smoking article, comprising at least 10 dry weight percent of
cellulosic pulp derived from stalks, roots, or a combination
thereof of a plant of the Nicotiana species, wherein the filter
material is in the form of a paper comprising the cellulosic pulp
or a fibrous tow comprising the cellulosic pulp in esterified
form.
2. The filter material of claim 1, wherein the filter material is
in the form of a paper that is pleated to form a rod-like
element.
3. The filter material of claim 2, wherein the web of sheet-like
material has a basis weight of about 20 gsm to about 90 gsm.
4. The filter material of claim 1, wherein the filter material
comprises at least 20 dry weight percent of cellulosic pulp derived
from stalks, roots, or a combination thereof of a plant of the
Nicotiana species.
5. A filter element for a smoking article comprising one or more
segments of a filter material according to claim 1.
6. A cigarette comprising a tobacco rod having a smokable filler
material contained within a circumscribing wrapping material and a
filter element connected to the tobacco rod at one end of the
tobacco rod, said filter element comprising at least one segment of
a filter material according to claim 1.
7. A method for formation of a filter element of a smoking article,
the method comprising: i) pulping a tobacco input comprising
stalks, roots, or a combination thereof of a plant of the Nicotiana
species to form a cellulosic pulp; ii) forming a web of sheet-like
material comprising the cellulosic pulp; and iii) pleating the web
of sheet-like material to form a rod-like element suitable for use
in a filter element.
8. The method of claim 7, wherein the web of sheet-like material
has a basis weight of about 20 gsm to about 90 gsm.
9. The method of claim 7, wherein the web of sheet-like material
comprises at least 10 dry weight percent of the cellulosic
pulp.
10. The method of claim 7, wherein the web of sheet-like material
comprises at least 20 dry weight percent of the cellulosic
pulp.
11. The method of claim 7, wherein the rod-like element is adapted
for use as a filter element in a smoking article.
12. A method for formation of a filter element of a smoking
article, the method comprising: i) pulping a tobacco input
comprising stalks, roots, or a combination thereof of a plant of
the Nicotiana species to form a cellulosic pulp; ii) esterifying
the cellulosic pulp to produce cellulose acetate; iii) dissolving
the cellulose acetate in a solvent to form a cellulose acetate
dope; iv) spinning the cellulose acetate dope into a plurality of
filaments; and v) collecting, drying and crimping the plurality of
filaments to form a tow material suitable for use in a filter
element, the tow material comprising at least 10 dry weight percent
of cellulose acetate filaments made from the cellulosic pulp.
13. The method of claim 12, further comprising blending the tow
material with ethyl cellulose fibers, cellulose acetate-lignin
blended fibers, or a combination thereof to form a biodegradable
blend of filter tow material suitable for use in a filter
element.
14. The method of claim 12, wherein the tow material comprising at
least 20 dry weight percent of cellulose acetate filaments made
from the cellulosic pulp.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to tobacco products, such as
smoking articles (e.g., cigarettes), and in particular, to filters
for cigarettes. The invention is directed to tobacco-derived
materials that can be useful as a filtration media.
BACKGROUND OF THE INVENTION
[0002] Popular smoking articles, such as cigarettes, have a
substantially cylindrical rod-shaped structure and include a
charge, roll or column of smokable material, such as shredded
tobacco (e.g., in cut filler form), surrounded by a paper wrapper,
thereby forming a so-called "smokable rod" or "tobacco rod."
Normally, a cigarette has a cylindrical filter element aligned in
an end-to-end relationship with the tobacco rod. Typically, a
filter element comprises plasticized cellulose acetate tow
circumscribed by a paper material known as "plug wrap." Typically,
the filter element is attached to one end of the tobacco rod using
a circumscribing wrapping material known as "tipping paper." It
also has become desirable to perforate the tipping material and
plug wrap, in order to provide dilution of drawn mainstream smoke
with ambient air. Descriptions of cigarettes and the various
components thereof are set forth in Tobacco Production, Chemistry
and Technology, Davis et al. (Eds.) (1999). A cigarette is employed
by a smoker by lighting one end thereof and burning the tobacco
rod. The smoker then receives mainstream smoke into his/her mouth
by drawing on the opposite end (e.g., the filter end) of the
cigarette.
[0003] The discarded portion of the cigarette rod is primarily
composed of the filter element, which typically consists of
tightly-compacted and highly crimped cellulose acetate fibers
bonded at their contact points and wrapped by the a plug wrap and
tipping paper. The presence of the wrapping materials, the
fiber-to-fiber bonding, and the compacted nature of conventional
filter elements has a detrimental effect on the rate of degradation
of cigarette filters in the environment. Unless the filter element
is unwrapped and the fibers spread apart to increase exposure,
biodegradation of the filter can take several years.
[0004] A number of approaches have been used in the art to promote
an increased rate of degradation of filter elements. One approach
involves incorporation of additives (e.g., water soluble cellulose
materials, water soluble fiber bonding agents, photoactive
pigments, or phosphoric acid) into the cellulose acetate material
in order to accelerate polymer decomposition. See U.S. Pat. No.
5,913,311 to Ito et al.; U.S. Pat. No. 5,947,126 to Wilson et al.;
U.S. Pat. No. 5,970,988 to Buchanan et al.; and U.S. Pat. No.
6,571,802 to Yamashita. In some cases, conventional cellulose
acetate has been replaced with other materials, such as moisture
disintegrative sheet materials, extruded starch materials, or
polyvinyl alcohol. See U.S. Pat. No. 5,709,227 to Arzonico et al;
U.S. Pat. No. 5,911,224 to Berger; U.S. Pat. No. 6,062,228 to
Loercks et al.; and U.S. Pat. No. 6,595,217 to Case et al.
Incorporation of slits into a filter element has been proposed for
enhancing biodegradability, such as described in U.S. Pat. No.
5,947,126 to Wilson et al. and U.S. Pat. No. 7,435,208 to
Garthaffner. U.S. Pat. No. 5,453,144 to Kauffman et al. describes
use of a water sensitive hot melt adhesive to adhere the plug wrap
in order to enhance biodegradability of the filter element upon
exposure to water. U.S. Pat. No. 6,344,349 to Asai et al, proposes
to replace conventional cellulose acetate filter elements with a
filter element comprising a core of a fibrous or particulate
cellulose material coated with a cellulose ester to enhance
biodegradability. Still further, U.S. Pat. No. 8,434,498 to
Sebastian suggests addition of starch particles to cellulose
acetate fibers for purposes of increasing biodegradability of
cigarette filters, US Pat. App. Publ. No. 2012/0000477 to Sebastian
et al. suggests use of degradable adhesives for smoking article
wrapping materials, US Pat. App. Publ. No. 2013/0025610 to
Sebastian et al. suggests plasticizers for biodegradable filter
elements, and US Pat. App. Publ. Nos. 2013/0074853 to Sebastian et
al., 2014/0026909 to Sebastian, and 2014/0096783 to Sebastian et
al. describe various techniques for forming fiber blends with
enhanced biodegradability.
[0005] There remains a need in the art for a smoking article filter
exhibiting enhanced environmental degradation properties.
SUMMARY OF THE INVENTION
[0006] The present invention relates to a smoking article, and in
particular, a rod-shaped smoking article (e.g., a cigarette). The
smoking article includes a lighting end (i.e., an upstream end) and
a mouth end (i.e., a downstream end). A mouth end piece is located
at the extreme mouth end of the smoking article, and the mouth end
piece allows the smoking article to be placed in the mouth of the
smoker to be drawn upon. The mouth end piece has the form of a
filter element comprising a filter material. The filter material
can comprise at least 10 dry weight percent, or at least 20 dry
weight percent of cellulosic pulp derived from stalks, roots, or a
combination thereof of a plant of the Nicotiana species.
Furthermore, the filter material can be in the form of a paper
comprising the pulp or a fibrous tow comprising the pulp in
esterified form.
[0007] In various embodiments, the filter material can be in the
form of a paper that is pleated or fluted to form a rod-like
element. The web of sheet-like material can have a basis weight of
about 20 gsm to about 90 gsm.
[0008] In some embodiments, a filter element for a smoking article
can include one or more segments of a filter material comprising at
least 10 dry weight percent, or at least 20 dry weight percent of
cellulosic pulp derived from stalks, roots, or a combination
thereof of a plant of the Nicotiana species, wherein the filter
material can be in the form of a paper comprising the pulp or a
fibrous tow comprising the pulp in esterified form. In some
embodiments, a cigarette comprising a tobacco rod having a smokable
filler material contained within a circumscribing wrapping material
and a filter element connected to the tobacco rod at one end of the
tobacco rod can be provided, wherein the filter element includes at
least one segment of a filter material according to the present
invention.
[0009] The present invention further provides a method for
formation of a filter element of a smoking article, the method
comprising: i) pulping a tobacco input comprising stalks, roots, or
a combination thereof of a plant of the Nicotiana species to form a
cellulosic pulp; ii) forming a web of sheet-like material
comprising the cellulosic pulp; and iii) pleating the web of
sheet-like material to form a rod-like element suitable for use in
a filter element. In some embodiments, the web of sheet-like
material can have a basis weight of about 20 gsm to about 90 gsm.
In various embodiments, the web of sheet-like material can comprise
at least 10 dry weight percent, or at least 20 weight percent of
the cellulosic pulp. In certain embodiments, the rod-like element
can be adapted for use as a filter element in a smoking
article.
[0010] Also provided herein is a method for formation of a filter
element of a smoking article, the method comprising: i) pulping a
tobacco input comprising stalks, roots, or a combination thereof of
a plant of the Nicotiana species to form a cellulosic pulp; ii)
esterifying the cellulosic pulp to produce cellulose acetate; iii)
dissolving the cellulose acetate in a solvent to form a cellulose
acetate dope; iv) spinning the cellulose acetate dope into a
plurality of filaments; and v) collecting, drying and crimping the
plurality of filaments to form a tow material suitable for use in a
filter element, the tow material comprising at least 10 dry weight
percent, or at least 20 dry weight percent of cellulose acetate
filaments made from the cellulosic pulp. In certain embodiments,
the method can further comprise blending the tow material with
ethyl cellulose fibers, cellulose acetate-lignin blended fibers, or
a combination thereof to form a biodegradable blend of filter tow
material suitable for use in a filter element.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] In order to assist the understanding of embodiments of the
invention, reference will now be made to the appended drawings,
which are not necessarily drawn to scale. The drawings are
exemplary only, and should not be construed as limiting the
invention.
[0012] FIG. 1 is an exploded perspective view of a smoking article
having the form of a cigarette, showing the smokable material, the
wrapping material components, and the filter element of the
cigarette;
[0013] FIG. 2 is a cross-sectional view of an embodiment of a
filter element according to the invention; and
[0014] FIG. 3 is a cross-sectional view of another embodiment of a
filter element according to the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] The present inventions now will be described more fully
hereinafter with reference to the accompanying drawing. The
invention may be embodied in many different forms and should not be
construed as limited to the embodiments set forth herein; rather,
these embodiments are provided so that this disclosure will satisfy
applicable legal requirements. Like numbers refer to like elements
throughout. As used in this specification and the claims, the
singular forms "a," "an," and "the" include plural referents unless
the context clearly dictates otherwise.
[0016] As described herein, embodiments of the disclosure relate to
filter materials comprising tobacco-derived cellulosic pulp and to
methods for producing filtration media from tobacco, and related
systems, apparatuses, and products. In this regard, the
tobacco-derived filtration materials can be employed, for example,
in tobacco products suitable for oral use. Traditional cigarette
filter materials include cellulose acetate tow, gathered cellulose
acetate web, polypropylene tow, gathered cellulose acetate web,
gathered paper, strands of reconstituted tobacco, or the like.
However, cellulose acetate can be slow to degrade. Accordingly, as
discussed in more detail below, the present invention provides
biodegradable filter materials that at least partially include
cellulosic pulp derived from a plant of the Nicotiana species.
[0017] Pulp is conventionally produced from wood or other cellulose
materials. However, as described herein, it can be desirable to
instead produce pulp derived from alternative sources, such as, for
example, tobacco. In some embodiments the tobacco input can
comprise one or more components from a plant of the Nicotiana
species including leaves, seeds, flowers, stalks, roots, and/or
stems. For example, as described below, in some embodiments the
tobacco input can comprise flue-cured tobacco stalks, burley
tobacco stalks, and/or whole-plant tobacco biomass (e.g., extracted
green tobacco biomass). It can be advantageous to use roots,
stalks, or a combination thereof from a plant of the Nicotiana
species due to the relatively high portion of cellulose fibers in
these parts of the plant.
[0018] Cellulose is understood to be a polysaccharide of the
formula (C.sub.6H.sub.10O.sub.5).sub.n, wherein n can be a number
from about 10 to over 10,000. In plants (e.g., plants of the
Nicotiana species), cellulose is commonly found in a mixture with
hemicellulose, lignin, pectin, and other substances. For example,
analysis of green tobacco stalks has revealed the presence of
cellulose, hemi-cellulose, lignin, pectin, and sugars.
[0019] The tobacco stalks and/or roots can be separated into
individual pieces (e.g., roots separated from stalks, and/or root
parts separated from each other, such as big root, mid root, and
small root parts) or the stalks and roots may be combined. By
"stalk" is meant the stalk that is left after the leaf (including
stem and lamina) has been removed. "Root" and various specific root
parts useful according to the present invention may be defined and
classified as described, for example, in Mauseth, Botany: An
Introduction to Plant Biology: Fourth Edition, Jones and Bartlett
Publishers (2009) and Glimn-Lacy et al., Botany Illustrated, Second
Edition, Springer (2006), which are incorporated herein by
reference. The harvested stalks and/or roots are typically cleaned,
ground, and dried to produce a material that can be described as
particulate (i.e., shredded, pulverized, ground, granulated, or
powdered).
[0020] Although the tobacco material may comprise material from any
part of a plant of the Nicotiana species, the majority of the
material advantageously comprises material obtained from the stalks
and/or roots of the plant. For example, in certain embodiments, the
tobacco material comprises at least about 80%, at least about 90%,
at least about 95%, or at least about 99% by dry weight of at least
one of the stalk material and the root material of a harvested
plant of the Nicotiana species.
[0021] Where the method employs stalks, entire stalks or only
portions of the stalks may be used in the process. The stalks may
be directly processed in harvested form or may be physically
altered by shredding or chopping prior to pulping. As an
alternative, the tobacco stalks may be prepared using a method by
which the fibrous structure of the stalk rind surrounding the pith
is used and the pith itself is isolated for another purpose. For
example, a splitter device can be used to separate the rind from
the pith. See, for example, U.S. Pat. Nos. 3,424,611, 3,424,612,
and 3,464,877 to Miller et al.; U.S. Pat. No. 4,151,004 to Vukelic;
and U.S. Pat. Nos. 3,567,510, 3,976,498, and 4,312,677 to Tilby et
al., each of which is incorporated herein by reference. These
references describe splitting methods to separate sugar cane into
its individual parts, which may be adapted for use with tobacco
stalks in accordance with the present invention. Thus, in some
embodiments, only the separated rind (rather than the entire
tobacco stalk itself) is processed as provided herein. It is to be
understood that reference to processing "stalks" is also intended
to encompass processing portions of stalks, e.g., separated rind
components.
[0022] The selection of the plant from the Nicotiana species (i.e.,
tobacco material) utilized in the products and processes of the
invention can vary; and in particular, the types of tobacco or
tobaccos may vary. Tobaccos that can be employed include flue-cured
or Virginia (e.g., K326), burley, sun-cured (e.g., Indian Kurnool
and Oriental tobaccos, including Katerini, Prelip, Komotini, Xanthi
and Yambol tobaccos), Maryland, dark, dark-fired, dark air cured
(e.g., Passanda, Cubano, Jatin and Bezuki tobaccos), light air
cured (e.g., North Wisconsin and Galpao tobaccos), Indian air
cured, Red Russian and Rustica tobaccos, as well as various other
rare or specialty tobaccos. Descriptions of various types of
tobaccos, growing practices and harvesting practices are set forth
in Tobacco Production, Chemistry and Technology, Davis et al.
(Eds.) (1999), which is incorporated herein by reference. Various
representative types of plants from the Nicotiana species are set
forth in Goodspeed, The Genus Nicotiana, (Chonica Botanica) (1954);
U.S. Pat. No. 4,660,577 to Sensabaugh, Jr. et al.; U.S. Pat. No.
5,387,416 to White et al.; U.S. Pat. No. 7,025,066 to Lawson et
al.; and U.S. Pat. No. 7,798,153 to Lawrence, Jr.; each of which is
incorporated herein by reference. Tobacco compositions including
dark air cured tobacco are set forth in U.S. Pat. No. 8,186,360 to
Marshall et al., which is incorporated herein by reference. See
also, types of tobacco as set forth, for example, in US Patent
Appl. Pub. No. 2011/0247640 to Beeson et al., which is incorporated
herein by reference.
[0023] Exemplary Nicotiana species include N. tabacum, N. rustica,
N. alata, N. arentsii, N. excelsior, N. forgetiana, N. glauca, N.
glutinosa, N, gossei, N. kawakamii, N. knightiana, N. langsdorffi,
N. otophora, N. setchelli, N. sylvestris, N. tomentosa, N.
tomentosiformis, N. undulata, N. x sanderae, N. africana, N.
amplexicaulis, N. benavidesii, N. bonariensis, N. debneyi, N.
longiflora, N. maritina, N. megalosiphon, N. occidentalis, N.
paniculata, N. plumbaginifolia, N. raimondii, N. rosulata, N.
simulans, N. stocktonii, N. suaveolens, N. umbratica, N. velutina,
N. wigandioides, N. acaulis, N. acuminata, N. attenuata, N.
benthamiana, N. cavicola, N. clevelandii, N. cordifolia, N.
corymbosa, N. fragrans, N. goodspeedii, N, linearis, N. miersii, N.
nudicaulis, N. obtusifolia, N. occidentalis subsp. Hersperis, N.
pauciflora, N. petunioides, N. quadrivalvis, N. repanda, N.
rotundifolia, N. solanifolia and N. spegazzinii.
[0024] Nicotiana species can be derived using genetic-modification
or crossbreeding techniques (e.g., tobacco plants can be
genetically engineered or crossbred to increase or decrease
production of components, characteristics or attributes). See, for
example, the types of genetic modifications of plants set forth in
U.S. Pat. No. 5,539,093 to Fitzmaurice et al.; U.S. Pat. No.
5,668,295 to Wahab et al.; U.S. Pat. No. 5,705,624 to Fitzmaurice
et al.; U.S. Pat. No. 5,844,119 to Weigl; U.S. Pat. No. 6,730,832
to Dominguez et al.; U.S. Pat. No. 7,173,170 to Liu et al.; U.S.
Pat. No. 7,208,659 to Colliver et al. and U.S. Pat. No. 7,230,160
to Benning et al.; US Patent Appl. Pub. No. 2006/0236434 to
Conkling et al.; and PCT WO 2008/103935 to Nielsen et al. See,
also, the types of tobaccos that are set forth in U.S. Pat. No.
4,660,577 to Sensabaugh, Jr. et al.; U.S. Pat. No. 5,387,416 to
White et al.; and U.S. Pat. No. 6,730,832 to Dominguez et al., each
of which is incorporated herein by reference.
[0025] Further, in some embodiments the tobacco input can comprise
reconstituted tobacco. Typically, tobacco stems are used in making
such a reconstituted tobacco sheet, because the fibrous nature of
those stems provides strength and structural integrity to the
resulting sheet. See, for example, U.S. Pat. No. 3,398,754 to
Tughan; U.S. Pat. No. 3,847,164 to Mattina; U.S. Pat. No. 4,131,117
to Kite; U.S. Pat. No. 4,182,349 to Selke; U.S. Pat. No. 4,270,552
to Jenkins; U.S. Pat. No. 4,308,877 to Mattina; U.S. Pat. No.
4,341,228 to Keritsis; U.S. Pat. No. 4,421,126 to Gellatly; U.S.
Pat. No. 4,706,692 to Gellatly; U.S. Pat. No. 4,962,774 to
Thomasson; U.S. Pat. No. 4,941,484 to Clapp; U.S. Pat. No.
4,987,906 to Young; U.S. Pat. No. 5,056,537 to Brown; U.S. Pat. No.
5,143,097 to Sohn; U.S. Pat. No. 5,159,942 to Brinkley et al.; U.S.
Pat. No. 5,325,877 to Young; U.S. Pat. No. 5,445,169 to Brinkley;
U.S. Pat. No. 5,501,237 to Young; and U.S. Pat. No. 5,533,530 to
Young, which are incorporated herein by reference.
[0026] Production of pulp derived from tobacco can involve a number
of operations. In general, pulps can be produced from raw materials
either mechanically or chemically, as is known in the art. In a
mechanical pulping process, raw tobacco materials can be chipped,
and then fed between refiners where the chips are made into fibers
between revolving metal disks, for example. For example, mechanical
pulping techniques can be used to produce tobacco pulp (i.e.,
tobacco-derived cellulosic pulp) from raw tobacco stalk, raw
tobacco root, or a combination thereof. The raw tobacco input can
be pretreated with water and then refined with a plurality of
passes through a machine that can chip the tobacco input, for
example. See, for example, the machines discussed in U.S. Pat. No.
3,661,192 to Nicholson et al.; U.S. Pat. No. 3,861,602 to Smith et
al.; U.S. Pat. No. 4,135,563 to Maucher; and U.S. Pat. No.
5,005,620 to Morey, each of which is incorporated by reference
herein. These chipped pulps can then be refined in a mill, for
example. See, for example, the methods and apparatuses discussed in
U.S. Pat. No. 6,773,552 to Albert et al.; and U.S. Appl. Pub. No.
2010/0036113 to Mambrim Filho et al, which are incorporated by
reference herein.
[0027] In some embodiments, a chemical pulping process can be used
to make a pulp from raw tobacco materials. A chemical pulping
process separates lignin from cellulose fibers by dissolving lignin
in a cooking liquor such that the lignin, which binds the cellulose
fibers together, can be washed away from the cellulose fibers
without seriously degrading the cellulose fibers. There are three
main chemical pulping processes known in the art. Soda pulping
involves cooking raw material chips in a sodium hydroxide cooking
liquor. The kraft process evolved from soda pulping and involves
cooking raw material chips in a solution of sodium hydroxide and
sodium sulfide. The acidic sulfite process involves using sulfurous
acid and bisulfate ion in the cook. Any chemical pulping process,
including, but not limited to the three examples listed above, can
be used to produce a tobacco pulp from raw tobacco materials.
[0028] A cooking liquor can comprise a strong base. As used herein,
a strong base refers to a basic chemical compound (or combination
of such compounds) that is able to deprotonate weak acids in an
acid-base reaction. For example, strong bases that can be useful in
the present invention include, but are not limited to one or more
of sodium hydroxide, potassium hydroxide, sodium sulfide, and
combinations thereof. In some embodiments, the weight of the strong
base can be greater than about 5%, greater than about 25%, or
greater than about 40% of the weight of the tobacco input. Various
other chemicals and weight ratios thereof can also be employed to
chemically pulp the tobacco input in other embodiments.
[0029] In addition to combining a tobacco input with a strong base,
chemically pulping a tobacco input can include heating the tobacco
input and the strong base. Heating the tobacco input and the strong
base can be conducted to increase the efficacy of the chemical
pulping. In this regard, an increase in either cooking temperature
or time will result in an increased reaction rate (rate of lignin
removal).
[0030] The method of producing a tobacco-derived pulp can include
one or more additional operations in some embodiments. See, e.g.,
U.S. Patent Appl. Pub. No. 2013/0276801 to Byrd Jr. et al., herein
incorporated by reference in its entirety. For example, the tobacco
input can undergo further processing steps prior to pulping and/or
the pulping method can include additional treatment steps (e.g.,
drying the tobacco input, depithing the tobacco input, milling the
tobacco input, etc.). In some embodiments, these additional steps
can be conducted to remove pith (which comprises lignin) from the
tobacco input and/or tobacco pulp manually, and thus reduce the
amount of chemicals necessary to delignify the tobacco input during
a chemical pulping process, for example. Mixing water with the
tobacco-derived cellulosic pulp to form a slurry and filtering the
slurry can be conducted, for example, to remove some of the
non-cellulosic materials, such as pith, parenchyma, and tissue from
the tobacco pulp. Additional treatment steps (e.g., milling the
tobacco input) can be conducted to increase the surface area of the
tobacco input such that the efficacy of a pulping and/or a
bleaching operation is increased. Steam- or water-based
pre-hydrolysis of the tobacco stalk prior to pulping, for example,
can reduce the amount of chemicals necessary in a bleaching
operation. Anthraquinone can be employed in a chemical pulping
method in an attempt to provide a higher yield by protecting
carbohydrates from the strong base during delignification, for
example. Other processing steps known in the papermaking art can be
employed in pulping the raw tobacco input.
[0031] The tobacco pulp can optionally be exposed to a bleaching
agent. The bleaching operation can be conducted to remove the
residual non-cellulosic materials left over after pulping without
damaging the cellulose. Exemplary processes for treating tobacco
with bleaching agents are discussed, for example, in U.S. Pat. No.
787,611 to Daniels, Jr.; U.S. Pat. No. 1,086,306 to Oelenheinz;
U.S. Pat. No. 1,437,095 to Delling; U.S. Pat. No. 1,757,477 to
Rosenhoch; U.S. Pat. No. 2,122,421 to Hawkinson; U.S. Pat. No.
2,148,147 to Baier; U.S. Pat. No. 2,170,107 to Baier; U.S. Pat. No.
2,274,649 to Baier; U.S. Pat. No. 2,770,239 to Prats et al.; U.S.
Pat. No. 3,612,065 to Rosen; U.S. Pat. No. 3,851,653 to Rosen; U.S.
Pat. No. 3,889,689 to Rosen; U.S. Pat. No. 4,143,666 to Rainer;
U.S. Pat. No. 4,194,514 to Campbell; U.S. Pat. No. 4,366,824 to
Rainer et al.; U.S. Pat. No. 4,388,933 to Rainer et al.; and U.S.
Pat. No. 4,641,667 to Schmekel et al.; and PCT WO 96/31255 to
Giolvas, all of which are incorporated by reference herein.
[0032] Once a suitable pulp is achieved, the pulp can optionally be
refined to modify the surface structure of the fibers. Refining can
physically modify fibers to fibrillate and make the fibers more
flexible, such that better bonding can be achieved. Additionally,
other additives known in the art can be used to alter
characteristics of the pulp fibers.
[0033] In various embodiments of the present invention, a tobacco
pulp can be used to produce a web of sheet-like material (i.e., a
paper). As used herein, the term "paper" is meant to include any
sheet or board made from a fibrous cellulosic material and
encompasses paperboard. In various embodiments, the thickness of
paper (i.e., caliper), is expressed in mils or points; however,
both one mil and one point are equivalent to 0.001 inches. Density
is expressed in mass per unit volume and bulk is the reciprocal of
density. The paper filter material disclosed herein has various
potential uses in filter elements; however, possible uses of the
paper filter material are not limited to the embodiments discussed
herein.
[0034] There are a variety of paper grades that can be tailored for
a particular end use. Exemplary processes for making paper are
discussed, for example, in U.S. Pat. No. 2,795,545 to Gluesenkamp;
U.S. Pat. No. 3,224,927 to Brown; U.S. Pat. No. 3,253,978 to
Bodendorf; U.S. Pat. No. 3,647,684 to Malcolm; U.S. Pat. No.
4,210,490 to Taylor; U.S. Pat. Nos. 4,385,961 and 4,388,150 to
Sunder et al.; U.S. Pat. No. 4,643,801 to Johnson; U.S. Pat. No.
4,749,444 to Aktiengesellschaft; U.S. Pat. No. 4,753,710 to Langley
et al.; and U.S. Pat. No. 5,071,512 to Bixler et al, all of which
are incorporated by reference herein. Various machines known in the
art can be used in a papermaking process. Exemplary machines used
to make paper are discussed, for example, in U.S. Pat. No.
3,691,010 to Krake; U.S. Pat. No. 4,102,737 to Morton; U.S. Pat.
No. 6,248,210 to Edwards et al.; U.S. Pat. No. 7,291,249 to
Thoroe-Scherb et al.; U.S. Pat. No. 8,377,262 to Quigley; and U.S.
Pat. No. 8,414,741 to Klerelid et al, all of which are incorporated
by reference herein.
[0035] In various embodiments, the paper material of the present
invention can comprise at least 10%, at least 20%, at least 50%, or
at least 75% of pulp derived from stalks, roots, or a combination
thereof of a plant of the Nicotiana species. In certain
embodiments, the paper material can comprise 100% pulp derived from
stalks, roots, or a combination thereof of a plant of the Nicotiana
species. In some embodiments, the paper material can include a
blend of pulp derived from stalks, roots, or a combination thereof
of a plant of the Nicotiana species and pulp derived from other
cellulose materials such as wood, for example.
[0036] In various embodiments of the present invention, a paper
material comprising pulp derived from stalks, roots, or a
combination thereof of a plant of the Nicotiana species can be used
to form a biodegradable filter element useful in a smoking article.
As illustrated in FIG. 2, for example, a web of sheet-like material
can be passed through a web preforming unit and pleated to form a
rod-like element 105 comprising a plurality of pleats 115. See, for
example, the filters, apparatuses and methods discussed in U.S.
Pat. No. 4,807,809 to Pryor et al., herein incorporated by
reference in its entirety. The rod-like element 105 can then be
circumscribed with wrapping material 110 thereby forming a
continuous rod 100 that can be used as a filter element or a
segment of a filter element, for example. The width of the
sheet-like material can vary and typically is a width capable of
being pleated to form the rod. The total width of the strip
employed in providing a desired rod can depend upon factors such as
the thickness of the sheet-like material, the number of pleats
desired, the nature or character of the pleats produced, the
surface character of the material (i.e., a fibrous surface
character versus a smooth surface), the porosity of the material,
the moisture content of the material, the lubricity properties of
the material, the friction characteristics of the web preforming
apparatus relative to the sheet-like material, and other such
factors. If desired, the tobacco-derived paper material can be
embossed.
[0037] Several characteristics known in the art can be used to
characterize the web of sheet-like material (i.e., paper). Basis
weight and caliper are two parameters used to characterize paper.
In some embodiments, the basis weights of paper comprising tobacco
pulp described herein can range from about 20 to about 90
g/m.sup.2, about 30 to about 60 g/m.sup.2, or about 30 to about 45
g/m.sup.2. The caliper of tobacco paper described herein can range
from about 0.01 to about 4.0 mils, or about 0.01 to about 1.0 mils,
or about 0.01 to about 0.5 mils, for example.
[0038] Preferred sheet-like materials are thin, and have reasonably
high tensile strengths, resiliencies and relatively good
flexibilities. In particular, it is desirable that the web have a
good "hand" to hold a fold but not tear, crinkle, shatter or
otherwise break during the folding or pleating process. It is
desirable that the modulus of the web be such that pleating readily
occurs. In particular, the web should not be so hard that it does
not pleat, nor should the web be so soft that rods of poor
resiliency are provided. As such, the rod-like element of pleated
web can be provided at a high speed and can be enclosed within the
outer wrapping material.
[0039] As illustrated in FIG. 2, for example, rod 105 has a
substantially cylindrical shape and a generally circular cross
sectional shape. Preferably, the ends of the rod each form a plane
perpendicular to the longitudinal axis thereof. The rod most
preferably includes a plurality of longitudinally extending pleats
115 in the web of sheet-like material. The pleated web is contained
in a wrapping material 110 such as cigarette paper wrap or paper
plug wrap which is formed in a tubular shape around the pleats.
Filter rods can be produced using porous or non-porous plug
wrap.
[0040] In various embodiments of the present invention, a pulp from
stalks, roots, or a combination thereof of a plant of the Nicotiana
species can be used to produce a fibrous tow material that can be
useful as a filter element. The process for making filter elements
according to the invention can vary, but a process for making
cellulose acetate filter elements typically begins with forming
cellulose fibers. See, e.g., U.S. Pat. Pub. No. 2013/0180536 to
Sebastian, which is herein incorporated by reference in its
entirety. The first step in conventional cellulose acetate fiber
formation is esterifying a cellulose material. As discussed above,
traditionally wood is used as a cellulose material. However, the
present invention utilizes pulp derived from tobacco. The
tobacco-derived pulp can be used alone or in combination with pulp
derived from other cellulose materials. Cellulose is a polymer
formed of repeating units of anhydroglucose. Each monomer unit has
three hydroxyl groups available for ester substitution (e.g.,
acetate substitution). Cellulose esters may be formed by reacting
cellulose with an acid anhydride. To make cellulose acetate, the
acid anhydride is acetic anhydride. Cellulose pulp is typically
mixed with acetic anhydride and acetic acid in the presence of an
acid catalyst such as sulfuric acid. The esterification process of
cellulose will often result in essentially complete conversion of
the available hydroxyl groups to ester groups (e.g., an average of
about 2.9 ester groups per anhydroglucose unit). Following
esterification, the polymer is typically hydrolyzed to drop the
degree of substitution (DS) to about 2 to about 2.5 ester groups
per anhydroglucose unit. The resulting product can be produced in
flake form that can be used in subsequent processing.
[0041] To form a fibrous material, the cellulose acetate is
typically dissolved in a solvent (e.g., acetone, methanol,
methylene chloride, or mixtures thereof) to form a viscous
solution. The concentration of cellulose acetate in the solution is
typically about 15 to about 35 percent by weight. Additives such as
whitening agents (e.g., titanium dioxide) can be added to the
solution if desired. The resulting liquid is sometimes referred to
as a liquid "dope."
[0042] The cellulose acetate dope is spun into filaments using a
nonwoven fabric melt-spinning technique, which entails extruding
the liquid dope through a spinerette. The filaments pass through a
curing/drying chamber, which solidifies the filaments prior to
collection. The collected fibers are combined into a tow band,
crimped, and dried. Conventional crimp ratios are in the range of
1.2 to 1.8. The fibers are typically packaged in bales that are
suitable for later use in filter element formation processes.
[0043] The process of forming the actual filter element typically
involves mechanically withdrawing the cellulose acetate tow from
the bale and separating the fibers into a ribbon-like band. The tow
band is subjected to a "blooming" process wherein the tow band is
separated into individual fibers. Blooming can be accomplished, for
example, by applying different tensions to adjacent sections of the
tow band or applying pneumatic pressure. The bloomed tow band then
passes through a relaxation zone that allows the fibers to
contract, followed by passage into a bonding station. The bonding
station typically applies a plasticizer such as triacetin to the
bloomed fibers, which softens the fibers and allows adjacent fibers
to fuse together. The bonding process forms a homogenous mass of
fibers with increased rigidity. The bonded tow is then wrapped in
plug wrap and cut into filter rods. Cellulose acetate tow processes
are set forth, for example, in U.S. Pat. No. 2,953,838 to Crawford
et al. and U.S. Pat. No. 2,794,239 to Crawford et al., which are
incorporated by reference herein.
[0044] In various embodiments, the final cellulose acetate tow can
comprise at least 10%, at least 20%, at least 50%, or at least 75%
of esterified pulp derived from stalks, roots, or a combination
thereof of a plant of the Nicotiana species. In certain
embodiments, the cellulose acetate tow can comprise 100% esterified
pulp derived from stalks, roots, or a combination thereof of a
plant of the Nicotiana species. In some embodiments, the cellulose
acetate tow can include a blend of esterified pulp derived from
stalks, roots, or a combination thereof of a plant of the Nicotiana
species and esterified pulp derived from other cellulose materials
such as wood, for example. In certain embodiments, the tow material
comprising esterified tobacco pulp can be blended with ethyl
cellulose fibers, cellulose acetate-lignin blended fibers, or a
combination thereof to form a biodegradable blend of filter tow
material suitable for use in a filter element.
[0045] Filter element components or segments for filter elements
for multi-segment filtered cigarettes typically are provided from
filter rods that are produced using traditional types of
rod-forming units, such as those available as KDF-2 and KDF-3E from
Hauni-Werke Korber & Co. KG. As discussed above, the filter
rods of the present invention can comprise a filter material
comprising at least 10 dry weight percent of pulp derived from
stalks, roots, or a combination thereof of a plant of the Nicotiana
species, wherein the filter material is in the form of a paper
comprising the pulp or a fibrous tow comprising the pulp in
esterified form. Typically, filter material, such as filter tow
(i.e., pulp in esterified form), is provided using a tow processing
unit. An exemplary tow processing unit has been commercially
available as E-60 supplied by Arjay Equipment Corp., Winston-Salem,
N.C. Other exemplary tow processing units have been commercially
available as AF-2, AF-3, and AF-4 from Hauni-Werke Korber & Co.
KG. In addition, representative manners and methods for operating a
filter material supply units and filter-making units are set forth
in U.S. Pat. No. 4,281,671 to Byrne; U.S. Pat. No. 4,862,905 to
Green, Jr. et al.; U.S. Pat. No. 5,060,664 to Siems et al.; U.S.
Pat. No. 5,387,285 to Rivers; and U.S. Pat. No. 7,074,170 to
Lanier, Jr. et al. Other types of technologies for supplying filter
materials to a filter rod-forming unit are set forth in U.S. Pat.
No. 4,807,809 to Pryor et al. and U.S. Pat. No. 5,025,814 to Raker;
which are incorporated herein by reference.
[0046] Referring to FIG. 1, there is shown a smoking article 10 in
the form of a cigarette and possessing certain representative
components of a smoking article of the present invention. The
cigarette 10 includes a generally cylindrical rod 12 of a charge or
roll of smokable filler material contained in a circumscribing
wrapping material 16. The rod 12 is conventionally referred to as a
"tobacco rod." The ends of the tobacco rod 12 are open to expose
the smokable filler material. The cigarette 10 is shown as having
one optional band 22 (e.g., a printed coating including a
film-forming agent, such as starch, ethylcellulose, or sodium
alginate) applied to the wrapping material 16, and that band
circumscribes the cigarette rod in a direction transverse to the
longitudinal axis of the cigarette. That is, the band 22 provides a
cross-directional region relative to the longitudinal axis of the
cigarette. The band 22 can be printed on the inner surface of the
wrapping material (i.e., facing the smokable filler material), or
less preferably, on the outer surface of the wrapping material.
Although the cigarette can possess a wrapping material having one
optional band, the cigarette also can possess wrapping material
having further optional spaced bands numbering two, three, or
more.
[0047] At one end of the tobacco rod 12 is the lighting end 18, and
at the mouth end 20 is positioned a filter element 26. The filter
element 26 positioned adjacent one end of the tobacco rod 12 such
that the filter element and tobacco rod are axially aligned in an
end-to-end relationship, preferably abutting one another. Filter
element 26 may have a generally cylindrical shape, and the diameter
thereof may be essentially equal to the diameter of the tobacco
rod. The ends of the filter element 26 permit the passage of air
and smoke therethrough. The filter element 26 is circumscribed
along its outer circumference or longitudinal periphery by a layer
of outer plug wrap 28. In a multi-segment filter embodiment, the
outer plug wrap 28 overlies each of the segments so as to provide a
combined, multi-segment filter element.
[0048] The filter element 26 is attached to the tobacco rod 12
using tipping material (not pictured) that circumscribes both the
entire length of the filter element 26 and an adjacent region of
the tobacco rod 12. Examples of tipping materials are described,
for example, in U.S. Pat. No. 7,789,089 to Dube et al., and in U.S.
Pat. App. Publ. Nos. 2007/0215167 to Crooks et al., 2010/0108081 to
Joyce et al., 2010/0108084 to Norman et al., and 2013/0167849 to
Ademe et al.; and PCT Pat. App. Pub. No. 2013/160671 to Dittrich et
al., each of which is incorporated by reference herein. The inner
surface of the tipping material is fixedly secured to the outer
surface of the plug wrap 28 and the outer surface of the wrapping
material 16 of the tobacco rod, using a suitable adhesive; and
hence, the filter element and the tobacco rod are connected to one
another.
[0049] A ventilated or air diluted smoking article can be provided
with an optional air dilution means, such as a series of
perforations 30, each of which extend through the tipping material
and plug wrap 28. The optional perforations 30, shown in FIG. 1,
can be made by various techniques known to those of ordinary skill
in the art, such as laser perforation techniques. Alternatively,
so-called off-line air dilution techniques can be used (e.g.,
through the use of porous paper plug wrap and pre-perforated
tipping paper).
[0050] For cigarettes that are air diluted or ventilated, the
amount or degree of air dilution or ventilation can vary.
Frequently, the amount of air dilution for an air diluted cigarette
is greater than about 10 percent, generally is greater than about
20 percent, often is greater than about 30 percent, and sometimes
is greater than about 40 percent. Typically, the upper level for
air dilution for an air diluted cigarette is less than about 80
percent, and often is less than about 70 percent. As used herein,
the term "air dilution" is the ratio (expressed as a percentage) of
the volume of air drawn through the air dilution means to the total
volume and air and smoke drawn through the cigarette and exiting
the extreme mouth end portion of the cigarette. Various types of
cigarette papers are disclosed and referenced, for example, in U.S.
Pat. No. 5,220,930 to Gentry, herein incorporated by reference in
its entirety.
[0051] During use, the smoker lights the lighting end 18 of the
cigarette 10 using a match or cigarette lighter. As such, the
smokable material 12 begins to burn. The mouth end 20 of the
cigarette 10 is placed in the lips of the smoker. Thermal
decomposition products (e.g., components of tobacco smoke)
generated by the burning smokable material 12 are drawn through the
cigarette 10, through the filter element 26, and into the mouth of
the smoker. Following use of the cigarette 10, the filter element
26 and any residual portion of the tobacco rod 12 can be
discarded.
[0052] As illustrated in FIGS. 2 and 3, for example, the filter
element of the invention typically comprises one or more
longitudinally-extending rods or segments. Each rod or segment can
have varying properties and may include various materials capable
of filtration or adsorption of particulate matter and/or vapor
phase compounds. Typically, the filter element of the invention
includes 1 to 6 segments, frequently 2 to 4 segments. In one
preferred embodiment, the filter element includes a mouth end
segment and a tobacco end segment. Typical rod sizes range in
length from about 40 mm to about 140 mm, and from about 16 mm to
about 28 mm in circumference.
[0053] The production of multi-segment filter rods can be carried
out using the types of rod-forming units that traditionally have
been employed to provide multi-segment cigarette filter components.
Multi-segment cigarette filter rods can be manufactured using a
cigarette filter rod making device available under the brand name
Mulfi from Hauni-Werke Korber & Co. KG of Hamburg, Germany.
Representative types of filter designs and components, including
representative types of segmented cigarette filters, are set forth
in U.S. Pat. No. 4,920,990 to Lawrence et al.; U.S. Pat. No.
5,012,829 to Thesing et al.; U.S. Pat. No. 5,025,814 to Raker; U.S.
Pat. No. 5,074,320 to Jones et al.; U.S. Pat. No. 5,105,838 to
White et al.; U.S. Pat. No. 5,271,419 to Arzonico et al.; U.S. Pat.
No. 5,360,023 to Blakley et al.; U.S. Pat. No. 5,396,909 to Gentry
et al.; and U.S. Pat. No. 5,718,250 to Banerjee et al; US Pat.
Appl. Pub. Nos. 2002/0166563 to Jupe et al., 2004/0261807 to Dube
et al.; 2005/0066981 to Crooks et al.; 2006/0090769 to Woodson;
2006/0124142 to Zhang et al.; 2006/0144412 to Mishra et al.,
2006/0157070 to Belcastro et al.; and 2007/0056600 to Coleman, III
et al.; PCT Publication No. WO 03/009711 to Kim; PCT Publication
No. WO 03/047836 to Xue et al.; all of which are incorporated
herein by reference.
[0054] Multi-segment filter elements typically are provided from
so-called "six-up" filter rods, "four-up" filter rods and "two-up"
filter rods that are of the general format and configuration
conventionally used for the manufacture of filtered cigarettes can
be handled using conventional-type or suitably modified cigarette
rod handling devices, such as tipping devices available as Lab MAX,
MAX, MAX S or MAX 80 from Hauni-Werke Korber & Co. KG. See, for
example, the types of devices set forth in U.S. Pat. No. 3,308,600
to Erdmann et al.; U.S. Pat. No. 4,281,670 to Heitmann et al.; U.S.
Pat. No. 4,280,187 to Reuland et al.; U.S. Pat. No. 4,850,301 to
Greene, Jr. et al.; and U.S. Pat. No. 6,229,115 to Vos et al.; and
US Patent Application Publication Nos. 2005/0103355 to Holmes,
2005/1094014 to Read, Jr., and 2006/0169295 to Draghetti, each of
which is incorporated herein by reference.
[0055] An exemplary multi-segment filter element 200 configuration
is shown in FIG. 3; the filter including a first filter segment 205
positioned adjacent one end of the tobacco rod 12 (see, e.g., FIG.
1). The first filter segment 205 can include filter material 212
(e.g., cellulose acetate tow comprising esterified tobacco pulp).
Filter element 200 also possesses a second filter segment 210
longitudinally disposed relative to the first segment 205 and
positioned at the extreme mouth end of the cigarette 10. The second
filter segment 210 includes filter material 214. The filter
material 214 of the second filter segment 210 can be the same or
different from the filter material 212 of the first filter segment
205. For example, the first filter material 212 can be a cellulose
acetate tow comprising esterified tobacco pulp (or a pleated paper
material made from tobacco pulp) and the second filter material 214
can also be a cellulose acetate tow comprising esterified tobacco
pulp (or a pleated paper material made from tobacco pulp), or the
second filter material 214 can be a cellulose acetate tow that does
not include tobacco pulp.
[0056] The filter element could also include a cavity formed
between two filter material segments (not pictured). Still further,
the filter segment comprising tobacco pulp can be more centrally
located within the filter element with one or more filter segments
that do not contain tobacco pulp on each side. Alternatively, all
filter segments could include tobacco pulp. In some embodiments, a
filter element can comprise a first filter segment comprising a
first filter material in the form of a paper comprising pulp
derived from stalks, roots, or a combination thereof of a plant of
the Nicotiana species and a second filter segment comprising a
second filter material in the form of a fibrous tow comprising pulp
derived from stalks, roots, or a combination thereof of a plant of
the Nicotiana species. Other filter element arrangements could be
used without departing from the invention.
[0057] In some embodiments, a plurality of degradable particles can
be dispersed within the either or all of filter materials 212, 214.
If desired, the filter element can also incorporate other
components that have the ability to alter the properties of the
mainstream smoke that passes throughout the filter element, such as
adsorbent materials or flavorants. Exemplary adsorbent materials
include activated carbon and ion exchange resins, and exemplary
flavorants include flavorant-containing capsules and solid
botanical additives such as peppermint or spearmint leaves or other
plant-based flavorants in particulate form. See, for example, U.S.
Pat. No. 6,041,790 to Smith et al. and US Pat. Application
Publication Nos. 2004/0237984 to Figlar et al.; 2005/0268925 to
Schluter et al.; 2006/0130861 to Luan et al.; and 2006/0174899 to
Luan et al., which are incorporated herein by reference.
[0058] The dimensions of a representative cigarette 10 can vary.
Preferred cigarettes are rod-shaped, and can have diameters of
about 7.5 mm (e.g., circumferences of about 20 mm to about 27 mm,
often about 22.5 mm to about 25 mm); and can have total lengths of
about 70 mm to about 120 mm, often about 80 mm to about 100 mm. The
length of the filter element 30 can vary. Typical filter elements
can have total lengths of about 15 mm to about 40 mm, often about
20 mm to about 35 mm. For a typical dual-segment filter element,
the downstream or mouth end filter segment often has a length of
about 10 mm to about 20 mm; and the upstream or tobacco rod end
filter segment often has a length of about 10 mm to about 20
mm.
[0059] Various types of cigarette components, including tobacco
types, tobacco blends, top dressing and casing materials, blend
packing densities and types of paper wrapping materials for tobacco
rods, can be employed. See, for example, the various representative
types of cigarette components, as well as the various cigarette
designs, formats, configurations and characteristics, that are set
forth in Johnson, Development of Cigarette Components to Meet
Industry Needs, 52.sup.nd T.S.R.C. (September, 1998); U.S. Pat. No.
5,101,839 to Jakob et al.; U.S. Pat. No. 5,159,944 to Arzonico et
al.; U.S. Pat. No. 5,220,930 to Gentry and U.S. Pat. No. 6,779,530
to Kraker; US Patent Publication Nos. 2005/0016556 to Ashcraft et
al.; 2005/0066986 to Nestor et al.; 2005/0076929 to Fitzgerald et
al.; 2006/0272655 to Thomas et al.; 2007/0056600 to Coleman, III et
al.; and 2007/0246055 to Oglesby, each of which is incorporated
herein by reference. Most preferably, the entire smokable rod is
composed of smokable material (e.g., tobacco cut filler) and a
layer of circumscribing outer wrapping material.
[0060] Filter elements of the present invention can be incorporated
within the types of cigarettes set forth in U.S. Pat. No. 4,756,318
to Clearman et al.; U.S. Pat. No. 4,714,082 to Banerjee et al.;
U.S. Pat. No. 4,771,795 to White et al.; U.S. Pat. No. 4,793,365 to
Sensabaugh et al.; U.S. Pat. No. 4,989,619 to Clearman et al.; U.S.
Pat. No. 4,917,128 to Clearman et al.; U.S. Pat. No. 4,961,438 to
Korte; U.S. Pat. No. 4,966,171 to Serrano et al.; U.S. Pat. No.
4,969,476 to Bale et al.; U.S. Pat. No. 4,991,606 to Serrano et
al.; U.S. Pat. No. 5,020,548 to Farrier et al.; U.S. Pat. No.
5,027,836 to Shannon et al.; U.S. Pat. No. 5,033,483 to Clearman et
al.; U.S. Pat. No. 5,040,551 to Schlatter et al.; U.S. Pat. No.
5,050,621 to Creighton et al.; U.S. Pat. No. 5,052,413 to Baker et
al.; U.S. Pat. No. 5,065,776 to Lawson; U.S. Pat. No. 5,076,296 to
Nystrom et al.; U.S. Pat. No. 5,076,297 to Farrier et al.; U.S.
Pat. No. 5,099,861 to Clearman et al.; U.S. Pat. No. 5,105,835 to
Drewett et al.; U.S. Pat. No. 5,105,837 to Barnes et al.; U.S. Pat.
No. 5,115,820 to Hauser et al.; U.S. Pat. No. 5,148,821 to Best et
al.; U.S. Pat. No. 5,159,940 to Hayward et al.; U.S. Pat. No.
5,178,167 to Riggs et al.; U.S. Pat. No. 5,183,062 to Clearman et
al.; U.S. Pat. No. 5,211,684 to Shannon et al.; U.S. Pat. No.
5,240,014 to Deevi et al.; U.S. Pat. No. 5,240,016 to Nichols et
al.; U.S. Pat. No. 5,345,955 to Clearman et al.; U.S. Pat. No.
5,396,911 to Casey, III et al.; U.S. Pat. No. 5,551,451 to Riggs et
al.; U.S. Pat. No. 5,595,577 to Bensalem et al.; U.S. Pat. No.
5,727,571 to Meiring et al.; U.S. Pat. No. 5,819,751 to Barnes et
al.; U.S. Pat. No. 6,089,857 to Matsuura et al.; U.S. Pat. No.
6,095,152 to Beven et al; and U.S. Pat. No. 6,578,584 to Beven;
which are incorporated herein by reference. Still further, filter
elements of the present invention can be incorporated within the
types of cigarettes that have been commercially marketed under the
brand names "Premier" and "Eclipse" by R. J. Reynolds Tobacco
Company. See, for example, those types of cigarettes described in
Chemical and Biological Studies on New Cigarette Prototypes that
Heat Instead of Burn Tobacco, R. J. Reynolds Tobacco Company
Monograph (1988) and Inhalation Toxicology, 12:5, p. 1-58 (2000);
which are incorporated herein by reference.
[0061] Cigarette rods typically are manufactured using a cigarette
making machine, such as a conventional automated cigarette rod
making machine. Exemplary cigarette rod making machines are of the
type commercially available from Molins PLC or Hauni-Werke Korber
& Co. KG. For example, cigarette rod making machines of the
type known as MIA (commercially available from Molins PLC) or
PROTOS (commercially available from Hauni-Werke Korber & Co.
KG) can be employed. A description of a PROTOS cigarette making
machine is provided in U.S. Pat. No. 4,474,190 to Brand, at col. 5,
line 48 through col. 8, line 3, which is incorporated herein by
reference. Types of equipment suitable for the manufacture of
cigarettes also are set forth in U.S. Pat. No. 4,781,203 to La Hue;
U.S. Pat. No. 4,844,100 to Holznagel; U.S. Pat. No. 5,131,416 to
Gentry; U.S. Pat. No. 5,156,169 to Holmes et al.; U.S. Pat. No.
5,191,906 to Myracle, Jr. et al.; U.S. Pat. No. 6,647,870 to Blau
et al.; U.S. Pat. No. 6,848,449 to Kitao et al.; and U.S. Pat. No.
6,904,917 to Kitao et al.; and US Patent Application Publication
Nos. 2003/0145866 to Hartman; 2004/0129281 to Hancock et al.;
2005/0039764 to Barnes et al.; and 2005/0076929 to Fitzgerald et
al.; each of which is incorporated herein by reference.
[0062] The components and operation of conventional automated
cigarette making machines will be readily apparent to those skilled
in the art of cigarette making machinery design and operation. For
example, descriptions of the components and operation of several
types of chimneys, tobacco filler supply equipment, suction
conveyor systems and garniture systems are set forth in U.S. Pat.
No. 3,288,147 to Molins et al.; U.S. Pat. No. 3,915,176 to Heitmann
et al.; U.S. Pat. No. 4,291,713 to Frank; U.S. Pat. No. 4,574,816
to Rudszinat; U.S. Pat. No. 4,736,754 to Heitmann et al. U.S. Pat.
No. 4,878,506 to Pinck et al.; U.S. Pat. No. 5,060,665 to Heitmann;
U.S. Pat. No. 5,012,823 to Keritsis et al. and U.S. Pat. No.
6,360,751 to Fagg et al.; and US Patent Publication No.
2003/0136419 to Muller; each of which is incorporated herein by
reference. The automated cigarette making machines of the type set
forth herein provide a formed continuous cigarette rod or smokable
rod that can be subdivided into formed smokable rods of desired
lengths.
[0063] Preferred cigarettes of the present invention exhibit
desirable resistance to draw. For example, an exemplary cigarette
exhibits a pressure drop of between about 50 and about 200 mm water
pressure drop at 17.5 cc/sec. air flow. Preferred cigarettes
exhibit pressure drop values of between about 60 mm and about 180,
more preferably between about 70 mm to about 150 mm, water pressure
drop at 17.5 cc/sec. air flow. Typically, pressure drop values of
cigarettes are measured using a Filtrona Cigarette Test Station
(CTS Series) available from Filtrona Instruments and Automation
Ltd.
[0064] Many modifications and other embodiments of the invention
will come to mind to one skilled in the art to which this invention
pertains having the benefit of the teachings presented in the
foregoing description; and it will be apparent to those skilled in
the art that variations and modifications of the present invention
can be made without departing from the scope or spirit of the
invention. Therefore, it is to be understood that the invention is
not to be limited to the specific embodiments disclosed and that
modifications and other embodiments are intended to be included
within the scope of the appended claims. Although specific terms
are employed herein, they are used in a generic and descriptive
sense only and not for purposes of limitation.
* * * * *