U.S. patent application number 09/819477 was filed with the patent office on 2002-12-05 for reduced ignition propensity smoking article with a polysaccharide treated wrapper.
Invention is credited to Grider, David A., Ihrig, Arthur M., Zawadzki, Michael A..
Application Number | 20020179106 09/819477 |
Document ID | / |
Family ID | 25228268 |
Filed Date | 2002-12-05 |
United States Patent
Application |
20020179106 |
Kind Code |
A1 |
Zawadzki, Michael A. ; et
al. |
December 5, 2002 |
Reduced ignition propensity smoking article with a polysaccharide
treated wrapper
Abstract
A smoking article having reduced ignition propensity is
disclosed. The smoking article includes a tobacco column, a wrapper
surrounding the tobacco column and a filter element. The wrapper
has a base permeability, an untreated area and a least one discrete
area treated with a composition to reduce the base permeability.
The treated area is treated with a composition initially comprising
a permeability reducing substance initially dissolved in a
non-derivatizing solvent mixture initially comprising a solvent
component and at least one ingredient that as part of the solvent
mixture is a self-association disruptor for the permeability
reducing substance. The discretely treated area interacts with a
coal of a burning tobacco firecone as it advances to
self-extinguish the smoking article. The composition of the treated
area includes a permeability reducing substance.
Inventors: |
Zawadzki, Michael A.;
(Greensboro, NC) ; Ihrig, Arthur M.; (Greensboro,
NC) ; Grider, David A.; (Greensboro, NC) |
Correspondence
Address: |
MACCORD MASON PLLC
300 N. GREENE STREET, SUITE 1600
P. O. BOX 2974
GREENSBORO
NC
27402
US
|
Family ID: |
25228268 |
Appl. No.: |
09/819477 |
Filed: |
March 28, 2001 |
Current U.S.
Class: |
131/365 |
Current CPC
Class: |
A24D 1/025 20130101 |
Class at
Publication: |
131/365 |
International
Class: |
A24F 047/00 |
Claims
We claim:
1. A smoking article having reduced ignition propensity comprising:
a tobacco column and a wrapper having a base permeability and
surrounding the tobacco column so that the smoking article includes
an ignition end and a distal end, the wrapper comprising: an
untreated area and a least one discrete area treated with a
composition comprising a permeability reducing substance initially
dissolved in a non-derivatizing solvent mixture initially
comprising a solvent and at least one ingredient that as part of
the non-derivatizing solvent mixture is a self-association
disruptor for the permeability reducing substance to reduce the
base permeability so that as a coal of a burning tobacco firecone
advances by the treated area, the smoking article self-extinguishes
if placed on a surface.
2. The smoking article of claim 1 wherein said smoking article is
one of a population of a plurality of smoking articles having a
reduced ignition propensity.
3. The smoking article of claim 2 wherein said at least one
discrete area treated is at least one banded region between the
ignition end and the distal end and a distance from the ignition
end to the at least one band of each smoking article within said
population of said plurality of smoking articles is at least one of
sequentially related, randomly related and quasi-randomly related
within said population.
4. The smoking article of claim 2 wherein said population of
smoking articles is a package of smoking articles.
5. The smoking article of claim 2 wherein said population of
smoking articles is a grab sample of smoking articles.
6. The smoking article of claim 2 wherein the ignition propensity
for the population is between about 50 percent and substantially
about 100 percent.
7. The smoking article of claim 2 wherein said at least one
discrete area treated is at least two spaced apart banded regions
and a distance from the ignition end to at least one band of each
smoking article is at least one of sequentially related, randomly
related and quasi-randomly related within said population.
8. The smoking article of claim 7 wherein said distance is
sequentially related.
9. The smoking article of claim 7 wherein said distance is randomly
related.
10. The smoking article of claim 7 wherein said distance is
quasi-randomly related.
11. The smoking article of claim 7 wherein said at least two banded
regions are spaced sufficiently to reduce the ignition propensity
of the smoking article.
12. The smoking article of claim 7 wherein said at least two banded
regions are spaced sufficiently to facilitate the freeburn of the
smoking article.
13. The smoking article of claim 7 wherein said at least two banded
regions have a width/center-to-center spacing ratio of at least
about 1/10 to greater than about 1/1.
14. The smoking article of claim 7 wherein said at least two banded
regions have a width of at least about 3 millimeters to about 10
millimeters.
15. The smoking article of claim 7 wherein said at least two banded
regions have a center-to-center spacing of about 10 millimeters to
about 30 millimeters.
16. The smoking article of claim 7 wherein said at least two banded
regions are visually substantially the same as unbanded
regions.
17. A wrapper for surrounding a tobacco column to create a smoking
article having reduced ignition propensity that includes an
ignition end and a distal end, the wrapper having a base
permeability and comprising: an untreated area and at least one
discrete area treated with a permeability reducing substance in an
amount equivalent to between about 0.3 micrograms per square
millimeter to about 1.2 micrograms per square millimeter of
substantially non-derivatized cellulose applied using lithium
chloride in dimethylacetamide (DMAC), said permeability reducing
substance applied using a composition comprising said permeability
reducing substance initially dissolved in a non-derivatizing
solvent mixture initially comprising a solvent and at least one
ingredient that as part of the non-derivatizing solvent mixture is
a self-association disruptor for the permeability reducing
substance to reduce the base permeability so that as a coal of a
burning tobacco firecone advances by the treated area, the smoking
article self-extinguishes if placed on a surface.
18. The wrapper according to claim 17 wherein said ingredient is a
salt.
19. The wrapper according to claim 18 wherein said salt is a
lithium containing compound.
20. The wrapper according to claim 19 wherein said lithium
containing compound is lithium chloride in an amount that
facilitates the dissolution of said permeability reducing substance
in said non-derivatizing solvent mixture while upon burning the
characteristic of ash for the untreated area and the at least one
treated area is substantially the same.
21. The wrapper according to claim 17 wherein said solvent
component is organic.
22. The wrapper according to claim 41 wherein said organic solvent
component is an amide.
23. The wrapper according to claim 22 wherein said amide is at
least one of dimethylacetamide (DMAC) and N-methylpyrrolidone
(NMP).
24. The wrapper according to claim 20 wherein said solvent
component is organic.
25. The wrapper according to claim 24 wherein said organic solvent
component is an amide.
26. The wrapper according to claim 25 wherein said amide is at
least one of dimethylacetamide (DMAC) and N-methylpyrrolidone
(NMP).
27. The wrapper according to claim 17 wherein said permeability
reducing substance is a pore filling substance, such that pores are
filled to reduce the permeability of the at least one treated
area.
28. The wrapper according to claim 17 wherein said permeability
reducing substance is a film forming substance, such that a film is
formed to reduce the permeability of said at least one treated
area.
29. The wrapper according to claim 17 wherein said permeability
reducing substance is a polymer.
30. The wrapper according to claim 29 wherein said polymer is a
polysaccharide.
31. The wrapper according to claim 30 wherein said polysaccharide
is a starch.
32. The wrapper according to claim 31 wherein said starch is
substantially non-derivatized.
33. The wrapper according to claim 30 wherein the polysaccharide is
a cellulose.
34. The wrapper according to claim 33 wherein the cellulose is
substantially non-derivatized.
35. The wrapper according to claim 30 wherein to the polysaccharide
is a chitosan.
36. The wrapper according to claim 35 wherein chitosan is
substantially non-derivatized.
37. The wrapper according to claim 30 wherein the polysaccharide is
a chitin.
38. The wrapper according to claim 37 wherein the chitin is
substantially non-derivatized.
39. The wrapper according to claim 30 wherein the polysaccharide is
an alginate.
40. The wrapper according to claim 39 wherein the alginate is
substantially non-derivatized.
41. The wrapper according to claim 17 wherein the discretely
treated area comprises a band.
42. The wrapper according to claim 41 wherein the band has a
sufficient width so as to deprive the coal of the burning tobacco
firecone of oxygen from behind a char line of the wrapper.
43. The wrapper according to claim 41 wherein the band has a width
of at least about 3 millimeters.
44. The wrapper according to claim 17 wherein the discretely
treated area comprises at least two bands spaced sufficiently to
reduce the ignition propensity of the smoking article.
45. The wrapper according to claim 44 wherein the at least two
bands have widths and are spaced apart so that a width to
center-to-center spacing ratio is between about 1/10 and about
1/1.
46. The wrapper according to claim 45 wherein the at least two
bands have widths between about 3 millimeters and about 10
millimeters.
47. The wrapper according to claim 45 wherein the at least two
bands have a center-to-center spacing of about 10 millimeters to
about 30 millimeters.
48. The wrapper according to claim 17 that has properties that
enable a bobbin of wrapper to be useable in a conventional
commercially available cigarette manufacturing machine.
49. The wrapper according to claim 17 wherein the treated area is
visually substantially the same untreated area.
50. The wrapper according to claim 17 wherein the treated area
further includes a filler.
51. The wrapper according to claim 50 wherein the filler is at
least one of clay, talc, calcium carbonate, and titanium oxide.
52. A smoking article having reduced ignition propensity
comprising: a tobacco column and a wrapper having a base
permeability and surrounding the tobacco column so that the smoking
article includes an ignition end and a distal end, the wrapper
comprising: an untreated area and a least one discrete area treated
with a permeability reducing substance in an amount equivalent to
between about 0.3 micrograms per square millimeter to about 1.2
micrograms per square millimeter of substantially non-derivatized
cellulose applied using lithium chloride in dimethylacetamide
(DMAC), said permeability reducing substance applied using a
composition comprising said permeability reducing substance
initially dissolved in a non-derivatizing solvent mixture initially
comprising a solvent component and at least one ingredient that as
part of the non-derivatizing solvent mixture is a self-association
disrupter for the permeability reducing substance to reduce the
base permeability so that as a coal of a burning tobacco firecone
advances by the treated area, the smoking article self-extinguishes
if placed on a surface, wherein said smoking article is one of a
population of a plurality of smoking articles having a reduced
ignition propensity.
53. The smoking article of claim 52 wherein said at least one
discrete area treated is at least one banded region between the
ignition end and the distal end and a distance from the ignition
end to the at least one band of each smoking article within said
population of said plurality of smoking articles is at least one of
sequentially related, randomly related and quasi-randomly related
within said population.
54. The smoking article of claim 52 wherein said population of
smoking articles is a package of smoking articles.
55. The smoking article of claim 5 wherein said population of
smoking articles is a grab sample of smoking articles.
56. The smoking article of claim 52 wherein the ignition propensity
for the population is between about 50 percent and substantially
about 100 percent.
57. The smoking article of claim 52 wherein said at least one
discrete area treated is at least two spaced apart banded regions
and a distance from the ignition end to at least one band of each
smoking article is at least one of sequentially related, randomly
related and quasi-randomly related within said population.
58. The smoking article of claim 57 wherein said distance is
sequentially related.
59. The smoking article of claim 57 wherein said distance is
randomly related.
60. The smoking article of claim 57 wherein said distance is
quasi-randomly related.
61. The smoking article of claim 57 wherein said at least two
banded regions are spaced sufficiently to reduce the ignition
propensity of the smoking article.
62. The smoking article of claim 57 wherein said at least two
banded regions are spaced sufficiently to facilitate the freeburn
of the smoking article.
63. The smoking article of claim 57 wherein said at least two
banded regions have a width/center-to-center spacing ratio of at
least about 1/10 to greater than about 1/1.
64. The smoking article of claim 57 wherein said at least two
banded regions have a width of at least about 3 millimeters to
about 10 millimeters.
65. The smoking article of claim 57 wherein said at least two
banded regions have a center-to-center spacing of about 10
millimeters to about 30 millimeters.
66. The smoking article of claim 57 wherein said at least two
banded regions are visually substantially the same as unbanded
regions.
67. The smoking article of claim 52 wherein said ingredient is a
salt.
68. The smoking article of claim 67 wherein said salt is a lithium
containing compound.
69. The smoking article of claim 68 wherein said lithium containing
compound is lithium chloride in an amount that facilitates the
dissolution of said permeability reducing substance in said
non-derivatizing solvent mixture while upon burning the
characteristic of ash for the untreated area and the at least one
treated area is substantially the same.
70. The smoking article of claim 52 wherein said solvent component
is organic.
71. The smoking article of claim 70 wherein said organic solvent
component is an amide.
72. The smoking article of claim 71 wherein said amide is at least
one of dimethylacetamide (DMAC) and N-methylpyrrolidone (NMP).
73. The smoking article of claim 69 wherein said solvent component
is organic.
74. The smoking article of claim 73 wherein said organic solvent
component is an amide.
75. The smoking article of claim 74 wherein said amide is at least
one of dimethylacetamide (DMAC) and N-methylpyrrolidone (NMP).
76. The smoking article of claim 52 wherein said permeability
reducing substance is a pore filling substance, such that pores are
filled to reduce the permeability of the at least one treated
area.
77. The smoking article of claim 52 wherein said permeability
reducing substance is a film forming substance, such that a film is
formed to reduce the permeability of said at least one treated
area.
78. The smoking article of claim 52 wherein said permeability
reducing substance is a polymer.
79. The smoking article of claim 78 wherein said polymer is a
polysaccharide.
80. The smoking article of claim 79 wherein said polysaccharide is
a starch.
81. The smoking article of claim 80 wherein said starch is
substantially non-derivatized.
82. The smoking article of claim 79 wherein the polysaccharide is a
cellulose.
83. The smoking article of claim 82 wherein the cellulose is
substantially non-derivatized.
84. The smoking article of claim 79 wherein to the polysaccharide
is a chitosan.
85. The smoking article of claim 84 wherein chitosan is
substantially non-derivatized.
86. The smoking article of claim 79 wherein the polysaccharide is a
chitin.
87. The smoking article of claim 86 wherein the chitin is
substantially non-derivatized.
88. The smoking article of claim 79 wherein the polysaccharide is
an alginate.
89. The smoking article of claim 88 wherein the alginate is
substantially non-derivatized.
90. The smoking article of claim 52 wherein the discretely treated
area comprises a band.
91. The smoking article of claim 90 wherein the band has a
sufficient width so as to deprive the coal of the burning tobacco
firecone of oxygen from behind a char line of the wrapper.
92. The smoking article of claim 90 wherein the band has a width of
at least about 3 millimeters.
93. The smoking article of claim 52 wherein the discretely treated
area comprises at least two bands spaced sufficiently to reduce the
ignition propensity of the smoking article.
94. The smoking article of claim 93 wherein the at least two bands
have widths and are spaced apart so that a width to
center-to-center spacing ratio is between about 1/10 and about
1/1.
95. The smoking article of claim 94 wherein the at least two bands
have widths between about 3 millimeters and about 10
millimeters.
96. The smoking article of claim 94 wherein the at least two bands
have a center-to-center spacing of about 10 millimeters to about 30
millimeters.
97. The smoking article of claim 52 that has properties that enable
a bobbin of wrapper to be useable in a conventional commercially
available cigarette manufacturing machine.
98. The smoking article of claim 52 wherein the treated area is
visually substantially the same untreated area.
99. The smoking article of claim 52 wherein the treated area
further includes a filler.
100. The smoking article of claim 99 wherein the filler is at least
one of clay, talc, calcium carbonate, and titanium oxide.
101. A composition for application to a paper having a base
permeability to create a wrapper having at least one discretely
treated area with a permeability reducing substance in an amount
equivalent to between about 0.3 micrograms per square millimeter to
about 1.2 micrograms per square millimeter of substantially
non-derivatized cellulose and suitable for surrounding a tobacco
column to create a smoking article having reduced ignition
propensity, said composition initially comprising a permeability
reducing substance initially dissolved in a solvent mixture
initially comprising an organic solvent component and at least one
ingredient that as part of the solvent mixture is a
self-association disrupter for the permeability reducing substance
such that when the wrapper is dry the at least one discretely
treated area has a reduced permeability.
102. The composition according to claim 101 wherein said ingredient
is a salt.
103. The composition according to claim 102 wherein said salt is a
lithium containing compound.
104. The composition according to claim 103 wherein said lithium
containing compound is lithium chloride in an amount that
facilitates the dissolution of said permeability reducing substance
in said non-derivatizing solvent mixture while upon burning the
characteristic of ash for the untreated area and the at least one
treated area is substantially the same.
105. The composition according to claim 101 wherein said organic
solvent component is at least one of dimethylacetamide (DMAC) and
N-methylpyrrolidone (NMP).
106. The composition according to claim 104 wherein said organic
solvent component is at least one of dimethylacetamide (DMAC) and
N-methylpyrrolidone (NMP).
107. The composition according to claim 101 wherein said
permeability reducing substance is a pore filling substance, such
that pores are filled to reduce the permeability of the at least
one treated area reducing permeability of the at least one treated
area.
108. The composition according to claim 101 wherein said
permeability reducing substance is a film forming substance, such
that a film is formed to reduce the permeability of said at least
one treated area.
109. The composition according to claim 101 wherein said
permeability reducing substance is a polymer.
110. The composition according to claim 109 wherein said polymer is
a polysaccharide.
111. The composition according to claim 110 wherein said
polysaccharide is a starch.
112. The composition according to claim 111 wherein said starch is
substantially non-derivatized.
113. The composition according to claim 110 wherein the
polysaccharide is a cellulose.
114. The composition according to claim 113 wherein the cellulose
is substantially non-derivatized.
115. The composition according to claim 110 wherein the
polysaccharide is a chitosan.
116. The composition according to claim 115 wherein the chitosan is
substantially non-derivatized.
117. The composition according to claim 110 wherein the
polysaccharide is a chitin.
118. The composition according to claim 117 wherein the chitin is
substantially non-derivatized.
119. The composition according to claim 110 wherein the
polysaccharide is an alginate.
120. The composition according to claim 119 wherein the alginate is
substantially non-derivatized.
121. The composition according to claim 101 wherein the discretely
treated area comprises a band.
122. The composition to according claim 121 wherein the band has a
sufficient width so as to deprive the coal of the burning tobacco
firecone of oxygen from behind a char line of the wrapper.
123. The composition according to claim 121 wherein the band has a
width of at least about 3 millimeters.
124. The composition according to claim 101 wherein the discretely
treated area comprises at least two bands spaced sufficiently to
reduce the ignition propensity of the smoking article.
125. The composition according to claim 124 wherein the at least
two bands have widths and are spaced apart so that a width to
center-to-center spacing ratio is between about 1/10 and about
1/1.
126. The composition according to claim 124 wherein the at least
two bands have widths between about 3 millimeters and about 10
millimeters.
127. The composition according to claim 124 wherein the at least
two bands have a center-to-center spacing of about 10 millimeters
to about 30 millimeters.
128. The composition according to claim 101 that has properties
that enable the manufacture of a bobbin of wrapper useable in a
conventional commercially available cigarette manufacturing
machine.
129. The composition according to claim 101 wherein the treated
area is visually substantially the same as the untreated area.
130. The composition according to claim 101 further including a
filler.
131. The composition according to claim 130 wherein the filler is
at least one of clay, talc and calcium carbonate.
132. A method for making a smoking article having reduced ignition
propensity comprising: treating a plurality of discrete areas of
paper having a base permeability with a composition initially
comprising a permeability reducing substance initially dissolved in
a solvent mixture initially comprising an organic component and at
least one ingredient that as part of the solvent mixture is a
self-association disruptor for the permeability reducing substance,
to form discrete areas having a reduced permeability in an amount
equivalent to that obtained with between about 0.3 micrograms per
square millimeter to about 1.2 micrograms per square millimeter of
substantially non-derivatized cellulose applied using lithium
chloride in dimethylacetamide (DMAC); and surrounding a tobacco
column with at least a portion of the wrapper so that at least one
discretely treated area substantially surrounds the tobacco column
between the ends of the wrapper-surrounded tobacco column so that
as a coal of a burning tobacco firecone advances by said at least
one treated area, the smoking article self-extinguishes if left on
a surface.
133. The method according to claim 132 wherein said ingredient is a
lithium containing compound.
134. The method according to claim 132 wherein said lithium
containing compound is lithium chloride in an amount that
facilitates the dissolution of said permeability reducing substance
in said non-derivatizing solvent mixture while upon burning the
characteristic of ash for the untreated area and the at least one
treated area is substantially the same.
135. The method according to claim 132 wherein said organic
component is at least one of dimethylacetamide (DMAC) and
N-methylpyrrolidone (NMP).
136. The method according to claim 134 wherein said organic
component is at least one of dimethylacetamide (DMAC) and
N-methylpyrrolidone (NMP).
137. The method according to claim 132 wherein said permeability
reducing substance is a pore filling substance thereby reducing
permeability of the at least one treated area.
138. The method according to claim 132 wherein said permeability
reducing substance is a film forming substance thereby reducing
permeability of said at least one treated area.
139. The method according to claim 132 wherein said permeability
reducing substance is a polysaccharide including at least one of a
starch, cellulose, chitosan, chitin, alginate and combinations
thereof.
140. The method according to claim 132 wherein said permeability
reducing substance is a polysaccharide including a cellulose.
141. The method according to claim 140 wherein the cellulose is
substantially non-derivatized.
142. The method according to claim 131 further including a
filler.
143. The method according to claim 142 wherein the filler is at
least one of clay, talc and calcium carbonate.
144. The method according to claim 131 further including at least
one of reducing and redistributing said at least one
ingredient.
145. The method according to claim 144 wherein said at least one of
reducing and redistributing includes applying water.
146. The method according to claim 145 further including at least
one of blotting and suctioning.
147. A method for making a wrapper for surrounding a tobacco column
to create a smoking article including a least one discrete area
treated with a composition to reduce a base permeability so that as
a coal of a burning tobacco firecone advances by said at least one
treated area, the smoking article self-extinguishes, the smoking
article thereby having reduced ignition propensity comprising:
treating a plurality of discrete areas of paper having a base
permeability with a composition initially comprising a permeability
reducing substance initially dissolved in a solvent mixture
initially comprising an organic component and at least one
ingredient that as part of the solvent mixture is a
self-association disruptor for the permeability reducing substance,
drying the discrete areas such that the discrete areas have a
reduced permeability in an amount equivalent obtained by applying
between about 0.3 micrograms per square millimeter to about 1.2
micrograms per square millimeter of substantially non-derivatized
cellulose applied using lithium chloride in dimethylacetamide
(DMAC) thereby forming a wrapper.
148. A method for making a smoking article having reduced ignition
propensity comprising: treating a plurality of discrete areas of
paper having a base permeability with a composition initially
comprising a permeability reducing substance initially dissolved in
a solvent mixture initially comprising an organic component and at
least one ingredient that as part of the solvent mixture is a
self-association disrupter for the permeability reducing substance,
to form discrete areas that have a reduced permeability in an
amount equivalent to that obtained by applying between about 0.3
micrograms per square millimeter to about 1.2 micrograms per square
millimeter of substantially non-derivatized cellulose applied using
lithium chloride in dimethylacetamide (DMAC), thereby forming a
wrapper; surrounding a tobacco column with at least a portion of
the wrapper so that at least one discretely treated area is found
between the ends of the wrapper-surrounded tobacco column so that
as a coal of a burning tobacco firecone advances by said at least
one treated area, the smoking article self-extinguishes if left on
a surface; and adding a filter element to at least one end of the
wrapper surrounded tobacco column.
149. A package of smoking articles having a reduced ignition
propensity comprising: a package; twenty smoking articles within
said package, each smoking article comprising: a tobacco column; a
wrapper surrounding said tobacco column so that the smoking article
includes an ignition end and a distal end; at least two spaced
apart banded regions between the ignition end and the distal end
having a combustion characteristic substantially different from
that of an unbanded region, the at least two banded regions being
treated with a composition in an amount equivalent to between about
0.3 micrograms per square millimeter to about 1.2 micrograms per
square millimeter of substantially non-derivatized cellulose
applied using lithium chloride in dimethylacetamide (DMAC); and a
distance from the ignition end to the at least one band of each
smoking article being at least one of sequentially related, random
and quasi-random within the population within the package.
150. A grab sample of smoking articles having a reduced ignition
propensity comprising: a plurality of smoking articles, each
smoking article comprising: a tobacco column; a wrapper surrounding
said tobacco column so that the smoking article includes an
ignition end and a distal end; at least two spaced apart banded
regions between the ignition end and the distal end having a
combustion characteristic substantially different from that of an
unbanded region, the at least two banded regions being treated with
a composition in an amount equivalent to between about 0.3
micrograms per square millimeter to about 1.2 micrograms per square
millimeter of substantially non-derivatized cellulose applied using
lithium chloride in dimethylacetamide (DMAC); and a distance from
the ignition end to the at least one band of each smoking article
being at least one of sequentially related, random and quasi-random
within the population.
151. A cigarette paper for use in making a cigarette having reduced
ignition propensity comprising: a fibrous paper having a base
permeability, an untreated area and a treated area, the treated
area being treated with a composition initially comprising a
permeability reducing substance initially dissolved in a solvent
mixture initially comprising an organic component and at least one
ingredient that as part of the solvent mixture is a
self-association disrupter for the permeability reducing substance
to reduce the base permeability so that when the paper is made into
a cigarette that is smoked, as a coal of a burning tobacco firecone
advances by the treated area, the cigarette self-extinguishes if
placed on a surface, the composition comprising: a permeability
reducing substance present in sufficient quantity to effect the
self-extinction; and a burn rate accelerating substance present in
sufficient quantity to cause a smoker's organoleptic experience to
be substantially indistinguishable from the organoleptic experience
of smoking the untreated area of the cigarette.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates generally to a wrapper for a
smoking article to create a reduced ignition propensity (IP)
smoking article and, more particularly, to a smoking article having
the ability to freeburn in a static state and reduced IP. Under
some circumstances cigarettes may ignite fire-prone substrates if
the article is laid or accidentally contacts the substrate.
Therefore, a cigarette prepared from a wrapper, which diminishes
the ability of the article to ignite a substrate, may have the
desirable effect of reducing cigarette-initiated fires.
Furthermore, a wrapper that concurrently confers on the cigarette
the ability to freeburn in a static state and reduced IP character
allows a beneficial reduction in the tendency of the article to
ignite fire-prone substrates while maintaining consumer
acceptability.
[0002] Cigarette manufacturers have struggled to create a cigarette
that has reduced IP and consumer acceptable attributes particularly
wrapper appearance and the ability to freeburn in the static state.
Technologies that appear to provide such cigarettes are described
in the patent literature. Cigarettes claiming to possess reduced IP
are commercially available.
[0003] A factor that manufacturers consider in preparing a smoking
article having reduced IP is whether currently used processes and
equipment will remain substantially unchanged. A method for
preparing a reduced IP paper involves the addition of elaborate
equipment on a conventional papermaking machine. A water-based
suspension, such as cellulose fibers or particles in water, is
sprayed from angular moving nozzles moving at an angle to a
continuously forming moist web. This approach involves the
coordinated angular movement of the spray nozzle and the about 400
feet per minute moving web to create spaced apart bands transverse
to the web. The above-mentioned technology suffers from a number of
deficiencies which limits consumer acceptability, IP reduction, and
ease of manufacture. The technology requires expensive add-on
equipment including a spray nozzle system and associated slurry
distribution system, pressure regulating system, and a means for
carefully synchronizing the angular material distribution system
with the underlying papermaking machine.
[0004] The reduced consumer acceptable properties of the prepared
cigarettes are due to factors including reduced ability of the
cigarette to freeburn in the static state, poor ash appearance, and
variable taste profile.
[0005] The poor IP reduction performance achieved by cigarettes
prepared with wrappers made using this technology is believed to be
caused by a number of factors including difficulty in depositing an
even layer of the permeability reducing slurry, low efficiency of
the slurry to reduce the permeability of the underlying web, and
poor reproducibility caused by fanning out of the sprayed
material.
[0006] One commercial product claiming to possess reduced IP is
characterized by a tendency to extinguish when left burning in the
static state, that is reduced freeburn. The article displays an
undesirable taste when relit after being extinguished. Thus,
although the cigarette may possess the reduced IP, the reduced
freeburn property decreases consumer acceptability of the
article.
[0007] Other factors affecting consumer acceptability are product
appearance, including pleasing and consistent wrapper appearance
and ash character. Moreover, it is important that the construction
of the smoking article exhibit a reasonable shelf life while
maintaining reduced IP.
[0008] Thus, there remains a need for a new and improved wrapper
and smoking article having reduced IP and sufficient free burn.
Also, there remains a need for a new and improved method for making
a wrapper that can be used to create a smoking article having
reduced IP and sufficient freeburn.
SUMMARY OF THE INVENTION
[0009] The present invention is directed to a smoking article
having reduced IP. The smoking article includes a tobacco column, a
wrapper surrounding the tobacco column and, optionally, a filter
element. The wrapper has a base permeability, an untreated area and
a least one discrete area treated with a composition to reduce the
base permeability. The discretely treated area interacts with the
coal of a burning tobacco firecone as it advances to
self-extinguish the smoking article if the smoking article is left
on a surface and causes the cigarette not to ignite the
surface.
[0010] The tendency of a cigarette to self-extinguish or not ignite
surfaces can be measured by the use of IP tests such as those
published by the Consumer Products Safety Commission and developed
by the National Institute of Standards and Technology (NIST) or the
American Society of Testing and Materials (ASTM). See Ohlemiller,
T. J. et al., "Test Methods for Quantifying the Propensity of
Cigarettes to Ignite Soft Furnishings. Volume 2.," NIST SP 851;
Volume 2; 166 pages [Also includes: Cigarette Extinction Test
Method, see pp. 153-160] August 1993 available from: U.S. Consumer
Product Safety Commission, Washington, DC 20207 as order number:
PB94-108644 the subject matter of which is herein incorporated by
reference. One NIST IP test, the "cotton duck test", involves
placing a smoldering cigarette on a test assembly composed of a
cellulosic fabric over a foam block. Variations of the test use
fabrics of various weights and polyethylene sheet backing. A test
failure occurs when the fabric ignites. Another NIST IP test, the
"filter paper test", involves placing a smoldering cigarette on a
test assembly composed of layered filter paper sheets. Various
forms of the test use 3, 10, and 15 layered filter paper sheets. A
successful test result occurs when the cigarette self extinguishes
before the whole tobacco column is consumed.
[0011] The composition of the treated area includes a permeability
reducing substance. Optionally, other substances in the treated
area may include one or more of a filler, a burn rate retarding
substance, a burn rate accelerating substance and a flavor
enhancing substance.
[0012] In a wrapper making process, the applied amount of the
permeability reducing substance is such as to give the desired
freeburn character and IP reduction to a finished article made from
the wrapper. The quantity and the concentration of the applied
composition will depend on factors including the absorbency of the
web, polymer properties of the permeability reducing substance, web
moisture content, and the operating conditions of the application
equipment.
[0013] The permeability reducing substance may be a pore filling
substance, a film forming substance or combination thereof. The
permeability reducing substance may be a polymer and, preferably, a
polysaccharide. Among the contemplated polysaccharides is
cellulose, including cellulose from any source, including cotton
linters, wood, paper, vegetable fiber, bacterial cellulose,
regenerated cellulose, amorphous cellulose, and crystalline
cellulose. The cellulose may be dispersible in a solvent mixture
and, preferably, is soluble. Other contemplated polysaccharides
include starch, including various mixtures of amylose, amylopectin
and dextrin, chitosan, chitosan derivatives, chitin, chitin
derivatives, alginate, alginate derivatives and combinations
thereof. The polysaccharides are preferably non-derivatized.
[0014] In one embodiment, the discretely treated area is a
circumferential band about the body of the article. The band has a
sufficient width so as to deprive the coal of the burning tobacco
firecone of oxygen from behind a char line of the wrapper when the
smoking article is placed on a surface. That may be achieved by a
band width typically of at least about 3 millimeters.
[0015] In an alternative embodiment, the discretely treated area
includes at least two bands spaced sufficiently to reduce the IP of
the smoking article. In this case, the two bands preferably have a
center-to-center spacing of between about 10 millimeters to about
30 millimeters. The two bands may have a width of about 3
millimeters to about 10 millimeters. A center-to-center spacing is
preferably about 25 millimeters.
[0016] The discretely treated area preferably has a thickness and
properties so a bobbin of the wrapper is useable in a commercially
available smoking article manufacturing machine. Also, the
discretely treated area is preferably visually substantially the
same as the untreated area.
[0017] Still another aspect of the present invention is to provide
a population of smoking articles having a reduced IP. Each smoking
article within the population includes a tobacco column, wrapper
surrounding said tobacco column so that the smoking article
includes an ignition end and a distal end, and at least one banded
region, preferably at least two spaced apart banded regions,
between the ignition end and the distal end having a combustion
characteristic substantially different from that of a non-banded,
untreated, region. A distance from the ignition end to the at least
one of the banded region of each smoking article may be one of
sequentially related, random, or quasi-random within the
population. Examples of the population include a package of smoking
articles and a grab sample of smoking articles.
[0018] In an embodiment, the distance from the ignition end to the
at least one of the banded region of each smoking article in the
population is at least one of sequentially related, random, and
quasi-random.
[0019] In a preferred embodiment, the IP of the selected population
is between about 50 and about 100 percent for the population.
[0020] The invention also provides a method of making a wrapper, of
making a smoking article having reduced IP, and a composition for
application to a paper to make a wrapper and a smoking article.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The invention will be better understood after a reading of
the following description of the preferred embodiment when
considered with the drawings in which:
[0022] FIG. 1 is a perspective view of a smoking article according
an embodiment of the present invention;
[0023] FIG. 2 is an exploded view of the smoking article of FIG.
1;
[0024] FIG. 3 is a perspective view of a bobbin of wrapper that may
be used to make the smoking article of FIG. 1;
[0025] FIG. 4 is a plan view of a wrapper as might be accumulated
in a bobbin as shown in FIG. 3;
[0026] FIG. 5A is an example of a population of smoking articles
having a substantially random distance from the ignition end to the
at least one of the banded regions of each smoking article within
the population according an embodiment of the present
invention;
[0027] FIG. 5B is an example of a population of smoking articles
having a quasi random distance from the ignition end to the at
least one of the banded regions of each smoking article within the
population according an embodiment of the present invention;
[0028] FIG. 5C is an example of a population of smoking articles
having a sequentially related distance from the ignition end to the
at least one of the banded regions of each smoking article within
the population according an embodiment of the present
invention;
[0029] FIG. 6 is a schematic of a package of smoking articles of
any of FIG. 1, FIG. 5A, FIG. 5B, and FIG. 5C; and
[0030] FIG. 7 shows ignition propensity for populations of
cigarettes of the present invention compared to the prior art.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0031] Referring now to the drawings in general and FIG. 1 in
particular, it will be understood that the illustrations are for
the purpose of describing a preferred embodiment of the invention
and are not intended to limit the invention thereto. As best seen
in FIG. 1, a smoking article 10 includes a tobacco column 12
surrounded by a wrapper 14. The smoking article 10 may, as an
option, include a filter element 16 adjacent to the tobacco column
12 surrounded by the wrapper 14.
[0032] FIG. 2 shows an exploded view of the smoking article 10 of
FIG. 1 including certain aspects relating to the wrapper 14, which
is a modified cigarette paper. In particular, wrapper 14 includes
untreated areas 20 alternating with treated areas 22. Discrete
areas 22 may include a combination of substances that interact with
the wrapper 14 to create the reduced IP smoking article 10. At
least one of the substances in treated area 22 includes a
permeability reducing substance. Optionally, other substances in
the treated area may include one or more of a filler, a burn rate
retarding substance, a burn rate accelerating substance and a
flavor enhancing substance. These substances interact with each
other and the wrapper paper 14 to create a wrapper that may be used
to manufacture reduced IP smoking article 10.
[0033] The permeability reducing substance may be a polymer. The
polymer may be any one of a natural polymer, a derivative of a
natural polymer, a synthetic polymer, and a combination of any of
the preceding. Applicants have found that polysaccharides are
suitable as permeability reducing substances. The polysaccharides
may be at least one of a starch, cellulose, chitosan, chitin,
alginate, or a combination of any of the preceding. Preferably, the
polysaccharides are non-derivatized. Any polysaccharide that
suitably reduces the permeability of the wrapper would be
appropriate for use as the permeability reducing substance.
[0034] Applicants believe that cellulose and starch would act
particularly well as permeability reducing substances. Applicants
have found that cellulose works particularly well as the
permeability reducing substance when applied using a solvent
mixture initially comprising an organic solvent component and at
least one ingredient that as part of the solvent mixture is a
self-association disrupter for cellulose. Applicants believe that
polysaccharides such as starch, cellulose, chitosan, chitin,
alginate, and a combination of any of the preceding may also work
well as the permeability reducing substance when applied using a
non-derivatizing solvent mixture initially comprising a solvent
component and at least one ingredient that as part of the solvent
mixture is a self-association disrupter.
[0035] The solvent component may include at least one of
dimethylacetamide (DMAC) and N-methylpyrrolidone (NMP). Synonyms
for dimethylacetamide (DMAC) include N,N-dimethylacetamide; acetic
acid, dimethylamide; dimethyl acetamide; acetdimethylamide;
dimethylamide acetate; and acetyldimethylamine. Synonyms for
N-methylpyrrolidone (NMP) include methylpyrrolidone;
1-methyl-5-pyrrolidinone; N-methyl-2-pyrrolidone;
1-methyl-2-pyrrolidone; 1-methylpyrrolidinone;
N-methylpyrrolidinone and N-methyl-2-pyrrolidinone.
[0036] The ingredient is a self-association disrupter such as a
salt, preferably one containing lithium, and more preferably,
lithium chloride.
[0037] An alternative solvent mixture for cellulose may initially
comprise a 4-methylmorpholine N-oxide as the solvent component and
water as the at least one ingredient that is a self-association
disruptor. Synonyms for 4-methylmorpholine N-oxide include
4-methylmorpholine N-oxide monohydrate; NMO monohydrate; and
N-methyl morpholine-N-oxide.
[0038] A preferred system for applying polysaccharides to a wrapper
according to the present invention includes a polysaccharide in
dimethylacetamide (DMAC) including lithium chloride (LiCl)
substantially as described in: U.S. Pat. No. 4,302,252 entitled
"Solvent System for Cellulose" issued Nov. 24, 1981 in the name of
Turbak et al.; U.S. Pat. No. 4,352,770 entitled "Process For
Forming Shaped Cellulosic Product" issued Oct. 5, 1982 in the name
of Turbak et al.; Maria Terbojevich et al. "Mesophase Formation and
Chain Rigidity in Cellulose and Derivatives. 3. Aggregation of
Cellulose in N,N-Dimethylacetamide-Lithium Cloride," Macromolecules
1985, 18, 640-646; Charles L. McCormick et al., "Solution Studies
of Cellulose in Lithium Chloride and N,N-Dimethylacetamide,"
Macromolecules 1985, 18, 2394-2401; K. J. Edgar et al., "Synthesis
and Properties of Cellulose Acetoacetates," Macromolecules 1995,
28, 4122-4128; Makoto Hasegawa et al., "Size-exclusion
Chromatography of Cellulose and Chitin Using Lithium
Chloride-N,N-Dimethylacetamide as a Mobile Phase," Journal of
Chromatography 1993, 635, 334-337; Lev Bromberg, "Salt-Mediated
Miscibility of Proteins and Polymers," Journal of Physical
Chemistry 1994, 98, 10628-10633; and Thomas J. Heinze, "New
Polymers by Unconventional Functionalization of Polyglucans,"
Friedrich Schiller University of Jena, Humboldstrasse 10, D-07743
Jena, Germany, publication date unknown
(http://www.chem-eng.nwu.edu/us-germany/abstract- s/heinze_abs.pdf)
copies of which are filed with this application and each being
hereby incorporated by reference in its entirety.
[0039] Without wishing to be bound by any scientific theory and
explanation, applicants believe that a permeability reducing
substance may interact with the wrapper in a number of ways. In
one, a permeability reducing substance may form a film on the
wrapper 14 to reduce permeability by blocking pores in the wrapper
14. That is, when the permeability reducing substance is applied to
the wrapper 14, a film is created that acts as a barrier to block
the movement of gas through pores in the discretely treated area
22.
[0040] Alternatively, a permeability reducing substance may act to
fill pores and thereby reduce the porosity of the wrapper 14. In
this way, a discretely treated area 22 possesses porosity or gas
permeability less than that of the untreated area 20 of the wrapper
14.
[0041] As a further alternative, a permeability reducing substance
may both form a film on the wrapper 14 and act to fill pores in the
wrapper 14 so that a discretely treated area 22 possesses a
porosity or gas permeability less than that of the untreated area
20 of the wrapper 14.
[0042] A manufacturing of discretely treated areas 22 may be made
by applying compositions that are applicable to the wrapper 14 when
the wrapper 14 might be in a wet or dry state or a semi-wet state.
Those skilled in the art will appreciate that the quantity and the
concentration of the applied composition will depend on factors
including the absorbency of the web, polymer properties of the
permeability reducing substance, web moisture content, and the
operating conditions of the application equipment. Moreover, those
skilled in the art will appreciate that the composition may be
applied by a number of known methods including spraying,
stenciling, offset, letterpress, flexographic, gravure printing,
and the like including both multiple-pass and single-pass
processes.
[0043] Preferably, the composition for affecting the discretely
treated areas may be applied on one side of the base paper such
that the formed band 22 faces the tobacco-side 12 after making
article 10 from the banded paper. Alternatively, the composition
may be applied on both sides of the paper or applied such that the
formed band 22 faces the outside or consumer-side after making
article 10 from the banded paper.
[0044] Manufacturing of reduced IP smoking articles is preferably
accomplished using a reel, or bobbin, length of wrapper 14 with
discretely treated areas 22 and untreated areas 20. Using a bobbin
of banded paper in a cigarette-making machine will provide a
population of banded smoking articles having a reduced IP. That is,
each smoking article within the population will include a tobacco
column, wrapper surrounding said tobacco column so that the smoking
article includes an ignition end and a distal end, and at least one
banded region, preferably at least two spaced apart banded regions,
between the ignition end and the distal end whereby the distance
from the ignition end to the at least one of the banded region of
each smoking article is sequentially related, random, or
quasi-random within the population.
[0045] Applicants believe that the sequentially related, random, or
quasi-random band position would have the benefit of allowing the
cigarette population as a whole to have fewer tendencies to ignite
fire-prone substrates. Overall, IP tests incorporate a fixed
burn-down distance in which the article is burned before being
placed on the test substrate. In real-world ignition scenarios the
article may burn down to any distance with respect to the ignition
end of the article before contacting a substrate. Therefore, a
sequentially related, random, or quasi-random band position will
increase the probability that any individual member of the banded
article population may prevent ignition of a prone substrate when
the article is burned down to a random distance before substrate
contact. Alternatively, bands may be registered at a fixed distance
with respect to the ignition end of article 10. The preferred
embodiment of this invention is for the manufacture of reduced IP
articles having a sequentially related, random, or quasi-random
band position with respect to the ignition end of article 10.
[0046] In each of the examples, sample cigarettes were prepared by
"hand banding" whereby a circumferential ring of material was
applied around the body of smoking article, by hand, using an
aluminum printing plate. The aluminum printing plate was fashioned
from a slab of aluminum metal with a straight channel, about 7
millimeters wide and about 30 millimeters long, milled below the
surface of the slab. A banding composition was used to fill the
channel of the printing plate. The smoking article was then rolled,
by hand, across the composition-filled channel such that a
circumferential band was formed about the body of the smoking
article. Therefore, the about 7 millimeter wide band was printed on
one side of the wrapper such that band 22 was on the outside or
consumer-side of article 10. Hand banded cigarettes are
characterized as having the applied band registered at a fixed
position with respect to the ignition end of the article.
[0047] In each of the examples, a conventional flax pulp cigarette
paper was used as a wrapper for the smoking articles. The cigarette
paper had the following properties: 18 CU (CORESTA units,
cm.sup.3/min/cm.sup.2 at 1 kPa measuring pressure) permeability, 30
weight percent calcium carbonate filler, 0.85 weight percent
citrate salt, and 25.5 g/m.sup.2 basis weight.
EXAMPLE 1
[0048] Cellulose/DMAC/lithium chloride compositions were used to
make circumferential bands, about 7 millimeters wide, around the
body of non-banded smoking articles. The circumferential band was
applied by hand and positioned about 15 millimeters from the
ignition end of the smoking article.
[0049] The non-banded smoking article was made using a conventional
paper wrapper, an about 72 millimeter tobacco column length, an
about 25 millimeter cellulose acetate non-air diluted filter
section, and a cigarette tobacco blend. Cigarettes were made on a
conventional cigarette-making machine.
[0050] Composition 1-1 was prepared by soaking about 20.60 grams
cellulose (Sigma-Aldrich, St. Louis, Mo.; Catalog #C-6663) in water
for 2 hours. The water was removed by filtration and then by
soaking the moist cellulose in about 150 milliliters DMAC. After
about 3 hours, the solvent was again removed by filtration. Then
the solvent-moist cellulose was added to about 400 milliliters of
DMAC containing about 40.4 grams lithium chloride. After stirring
for about two days a colorless, visually-homogeneous, composition
was produced.
[0051] Composition 1-2 was prepared by mixing about 7.4002 grams of
composition 1-1 with about 7.3 grams DMAC. Composition 1-3 was
prepared by mixing about 1.6 grams of composition 1-1 with about
9.3 grams DMAC. Composition 1-4 was prepared by mixing about 4.9
grams of composition 1-1 with about 22.1 grams DMAC. Composition
1-5 was prepared by dissolving lithium chloride in DMAC such that
lithium chloride concentration was about 10 weight percent
concentration.
[0052] Applicants found that the appearance of the cellulose band,
formed by the application of cellulose/DMAC/lithium chloride, was
nearly indistinguishable from the untreated areas of the wrapper. A
band composed of lithium chloride alone (Composition 1-5, Table 1)
was found to be ineffective for IP reduction.
[0053] Applicants also found that the char line on the wrapper, as
the banded article was smoked, displayed an increase in width as
the firecone traversed the cellulose/DMAC/lithium chloride banded
area. Applicants attribute the increase in char line width to the
presence of lithium chloride in the treated area. Therefore, the
preferable composition of the band is to contain the minimum
quantity of lithium chloride.
[0054] The IP data in Table 1 demonstrates that about 104
micrograms (.mu.g) dry cellulose, applied as cellulose/DMAC/lithium
chloride, forms a substantially 100% effective, IP reducing, about
7 millimeter wide band.
1TABLE 1 IP Results For Cellulose/DMAC/Lithium Chloride Banded
Cigarettes. Composition IP Pass (%)** Dry band weight (.mu.g)* 1-5
0.0 0 1-3 0.0 16 1-4 0.0 22 1-3 0.0 25 1-3 0.0 43 1-1 60.0 73 1-2
87.5 90 1-1 100.0 104 1-1 100.0 136 *Cellulose component; Average
weight on 8 treated cigarettes **NIST (#6) cotton duck IP test; 8
cigarettes studied
EXAMPLE 2
[0055] Cellulose/DMAC/lithium chloride composition 1-1 (Example 1)
was used to make circumferential bands, about 10 millimeters wide,
around the body of non-banded smoking articles. The circumferential
band was applied by hand-banding as previously described except the
channel of the printing plate was about 10 millimeters wide. The
band was positioned about 15 millimeters from the ignition end of
the smoking article.
[0056] The non-banded smoking article was made using a conventional
paper wrapper, an about 72 millimeter tobacco column length, an
about 25 millimeter cellulose acetate non-air diluted filter
section, and a cigarette tobacco blend. Cigarettes were made on a
conventional cigarette-making machine.
[0057] Applicants found that the appearance of the cellulose band,
formed by the application of cellulose/DMAC/lithium chloride, was
nearly indistinguishable from the untreated areas of the
wrapper.
[0058] The IP data in Table 2 demonstrates that about 110
micrograms (.mu.g) dry cellulose, applied as cellulose/DMAC/lithium
chloride, forms a substantially 100% effective, IP reducing, about
10 millimeter wide band.
2TABLE 2 IP Results For Cellulose/DMAC/Lithium Chloride Banded
Cigarettes. Composition IP Pass (%)** Dry band weight (.mu.g)* 1-1
100.0 110 1-1 100.0 290 *Cellulose component; Average weight on 8
treated cigarettes **NIST (#6) cotton duck IP test; 8 cigarettes
studied
EXAMPLE 3
[0059] Cellulose/DMAC/lithium chloride composition was used to make
circumferential bands, about 7 millimeters wide, around the body of
non-banded smoking articles. The circumferential band was applied
by hand and positioned about 15 millimeters from the ignition end
of the smoking article.
[0060] The non-banded smoking article was made using a conventional
paper wrapper, an about 72 millimeter tobacco column length, an
about 25 millimeter cellulose acetate non-air diluted filter
section, and a cigarette tobacco blend. Cigarettes were made on a
conventional cigarette-making machine.
[0061] Composition 3-1 was prepared by dissolving about 39.7 grams
lithium chloride in about 500 milliliters DMAC using stirring and
heating. After the lithium chloride dissolved, about 27.5 grams
cellulose (Sigma-Aldrich, St. Louis, Mo.; Catalog #C-6663) was
added to the DMAC/lithium chloride solution. The resulting mixture
was heated at about 135.degree. C. for about 1 hour, with
mechanical stirring. Then the mixture was allowed to cool and stand
for about 5 days at room temperature, after which a visually
homogeneous composition was produced.
[0062] Eight smoking articles were banded with composition 3-1 such
that the dry weight of cellulose in the treated region was about
230 micrograms. IP of the treated articles was measured by the NIST
#6 cotton duck IP test and gave a 100% pass rate.
EXAMPLE 4
[0063] Cellulose/NMP/lithium chloride composition was used to make
circumferential bands, about 7 millimeters wide, around the body of
non-banded smoking articles. The circumferential band was applied
by hand and positioned about 20 millimeters from the ignition end
of the smoking article.
[0064] The non-banded smoking article was made using a conventional
paper wrapper, an about 63 millimeter tobacco column length, an
about 21 millimeter cellulose acetate non-air diluted filter
section, and a cigarette tobacco blend. Cigarettes were made on a
conventional cigarette-making machine.
[0065] The cellulose/NMP/lithium chloride was prepared from about
105.5 grams microcrystalline cellulose (Aldrich, Milwaukee, Wis.;
Catalog #31,069-7) added to about 700 milliliters NMP. The mixture
was stirred and heated to about 170.degree. C. then allowed to cool
to about 110.degree. C. over 15 minutes. Then about 52.4 grams
lithium chloride was added and the mixture was held at about
110.degree. C. until the lithium chloride dissolved. The mixture
was allowed to gradually cool to room temperature. After stirring
overnight, a viscous and visually-homogeneous composition was
produced. The cellulose/NMP/lithium chloride composition, about
1.44 grams, was diluted with about 3 grams NMP to give composition
4-1.
[0066] Eight smoking articles were banded with composition 4-1 such
that the dry weight of cellulose in the treated region was about
160 micrograms. IP of the treated articles was measured by the NIST
10-sheet filter paper IP test and gave substantially a 100% pass
rate.
[0067] Eight smoking articles were banded with composition 4-1 such
that the dry weight of cellulose in the treated region was about
116 micrograms. IP of the treated articles was measured by the NIST
10-sheet filter paper IP test and gave substantially a 100% pass
rate.
[0068] Eight smoking articles were banded with composition 4-1 such
that the dry weight of cellulose in the treated region was about
112 micrograms. Freeburn of the treated articles was measured by
igniting a cigarette and placing the smoldering articles
horizontally in a holder. The articles were allowed to statically
smolder without the column or ember contacting a surface. A
positive freeburn result occurred when the cigarette was consumed
to the filter element. All 8 treated articles were found to
freeburn.
EXAMPLE 5
[0069] Starch/NMP composition was used to make circumferential
bands, about 7 millimeters wide, around the body of non-banded
smoking articles. The circumferential band was applied by hand and
positioned about 20 millimeters from the ignition end of the
smoking article.
[0070] The non-banded smoking article was made using a conventional
paper wrapper, an about 63 millimeter tobacco column length, an
about 21 millimeter cellulose acetate non-air diluted filter
section, and a cigarette tobacco blend. Cigarettes were made on a
conventional cigarette-making machine.
[0071] The starch/NMP composition was prepared from about 16.9
grams Flokote-64.RTM. starch (National Starch, Berkeley, Calif.)
mixed with about 100 milliliters NMP. The mixture was stirred and
heated to about 110.degree. C. then allowed to cool to room
temperature over about 1 hour. After cooling, a viscous and
visually-homogeneous composition was produced. The starch/NMP
composition, about 5 grams, was then diluted with about 5.1 grams
NMP to give composition 5-1.
[0072] Eight smoking articles were banded with composition 5-1 such
that the dry weight of starch in the treated region was about 1.4
milligrams. Composition 5-1 was applied on the articles as a double
layer band that is, a second band was overprinted a previously
applied, and dried, layer of composition 5-1. IP of the treated
articles was measured by the NIST 10-sheet filter paper IP test and
gave a 100% pass rate.
EXAMPLE 6
[0073] .beta.-Cyclodextrin/DMAC/lithium chloride composition was
used to make circumferential bands, about 7 millimeters wide,
around the body of non-banded smoking articles. The circumferential
band was applied by hand and positioned about 15 millimeters from
the ignition end of the smoking article.
[0074] The non-banded smoking article was made using a conventional
paper wrapper, an about 72 millimeter tobacco column length, an
about 25 millimeter cellulose acetate non-air diluted filter
section, and a cigarette tobacco blend. Cigarettes were made on a
conventional cigarette-making machine.
[0075] Composition 6-1 was prepared from about 5.3 grams
.beta.-cyclodextrin (Fluka Chemical, Milwaukee, Wis.; Catalog
#28707) added to about 10 milliliters DMAC and about 4 milliliters
DMAC containing about 9.8 weight percent lithium chloride.
.beta.-Cyclodextrin was dissolved by heating and stirring the
mixture at about 100.degree. C. for about one hour and then
allowing the mixture to stand overnight. Composition 6-2 was
prepared by mixing about 1 milliliter of composition 6-1 with about
5 milliliters DMAC.
[0076] Eight smoking articles were banded with composition 6-1 such
that the dry weight of .beta.-cyclodextrin in the treated region
was about 2.3 milligrams. IP of the treated articles was measured
by the NIST #6 cotton duck IP test and gave substantially a 100%
pass rate.
[0077] Eight smoking articles were banded with composition 6-2 such
that the dry weight of .beta.-cyclodextrin in the treated region
was about 440 micrograms. IP of the treated articles was measured
by the NIST #6 cotton duck IP test and gave substantially a 0% pass
rate.
EXAMPLE 7
[0078] The effectiveness of various permeability reducing agents
was compared using a conventional flax cigarette paper with the
following properties: about 32 CU permeability, about 28 weight
percent calcium carbonate, about 0.60 weight percent citrate salt,
and about 26.0 g/m.sup.2 basis weight.
[0079] About 20-centimeter lengths of paper were cut and
permeability-reducing compositions were evenly applied in an area
about 27.3 millimeters wide by about 32.5 millimeters long. After
treatment, the strips were stored overnight at about 75.degree. C.
and about 65% relative humidity. Permeability values for the
treated area were measured with a Filtrona PM-100 permeability unit
(1 kPa measuring pressure).
[0080] Composition 7-1 comprised about 16 weight percent starch
(National Starch, Berkeley, Calif., Item #51,6437) and about 84
weight percent water. Composition 7-1 was prepared by dispersing
the starch powder in cold water and heating the mixture for about
15 minutes at about 87.degree. C. Composition 7-2 comprised about
6.5 weight percent ethyl cellulose (Fisher Scientific, Fair Lawn,
N.J.; Catalog #E-152) and about 93.5 weight percent ethyl alcohol
solution (95 volume percent ethyl alcohol and 5 weight percent
water).
[0081] Composition 7-3 comprised about 11.9 weight percent ethyl
cellulose (Fisher Scientific, Fair Lawn, N.J.; Catalog #E-152) and
about 88.1 weight percent isopropyl acetate. Composition 7-4
comprised about 9.7 weight percent hydroxypropyl cellulose
(Aldrich, Milwaukee, Wis.; Catalog #43,500-7) and about 90.3 weight
percent deionized water. Composition 7-5 comprised about 6.0 weight
percent microcrystalline cellulose (Aldrich, Milwaukee, Wis.;
Catalog #43,524-4; cellulose powder coated with about 15 weight
percent sodium carboxymethylcellulose) and about 94.0 weight
percent deionized water.
[0082] Table 3 gives permeability values for paper treated
separately with cellulose/DMAC/lithium chloride, ethyl cellulose,
hydroxypropyl cellulose, cellulose/water, and starch/water
compositions. In all cases, application of the banding solution
caused a decrease in permeability relative to untreated paper. In
particular, applicants unexpectedly discovered that
cellulose/DMAC/lithium chloride is a very efficient permeability
reducing substance.
[0083] The mechanism by which low paper porosity may give reduced
IP is not known with certainty but may be due to oxygen starvation
of the firecone. When the cigarette is laid down on a substrate the
low permeability of the treated area may cause a reduction of
oxygen to the fire cone and consequently cause the article to
self-extinguish.
[0084] Cellulose/DMAC/lithium chloride has shown to be an
unexpectedly efficient permeability reducing substance which may
explain the minute quantity (as shown in Example 1 and others) that
are required to give a reduced IP article. Applicants believe that
other polysaccharides combined with self-association disrupter
solvent systems will display efficient permeability reducing
properties. Furthermore, the efficient permeability-reducing nature
of cellulose/DMAC/lithium chloride (and the like) make the
composition compatible with high-speed printing operations thereby
allowing for the efficient manufacture of reduced permeability
regions on a material such as paper.
3TABLE 3 Permeability Values of Banded Cigarette Paper. Band Weight
Banding Material (.mu.g/mm.sup.2)* Permeability (CU)
Cellulose/DMAC/Lithium Chloride 0.50 TLM (Composition 1-1) 0.73 TLM
0.79 TLM Starch (Composition 7-1) 2.51 3.6 2.75 2.0 Ethyl Cellulose
(Composition 7-2) 1.63 11.7 1.86 4.5 2.65 TLM Ethyl Cellulose
(Composition 7-3) 1.10 4.5 Hydroxypropyl cellulose 2.12 14.0
(Composition 7-4) Cellulose/Water (Composition 7-5) 1.38 20.2 *Dry
polymer weight per unit area TLM = Permeability value too low to
measure
EXAMPLE 8
[0085] The effectiveness of various permeability reducing agents
for smoking article IP reduction was compared. Compositions, as
listed in Table 4, were used to make circumferential bands, about 7
millimeters wide, around the body of non-banded smoking articles.
The circumferential band was applied by hand and positioned about
15 millimeters from the ignition end of the smoking article.
[0086] The non-banded smoking article was made using a conventional
paper wrapper, an about 72 millimeter tobacco column length, an
about 25 millimeter cellulose acetate non-air diluted filter
section, and a cigarette tobacco blend. Cigarettes were made on a
conventional cigarette-making machine.
[0087] Composition 8-1 comprised a suspension of about 5.1 weight
percent microcrystalline cellulose (Aldrich, Milwaukee, Wis.;
Catalog #43,524-4; cellulose powder coated with about 15 weight
percent sodium carboxymethylcellulose) and about 94.9 weight
percent deionized water.
[0088] Composition 8-2 comprised a suspension of about 9.10 weight
percent microcrystalline cellulose (Aldrich, Milwaukee, Wis.;
Catalog #43,524-4) and about 90.90 weight percent deionized
water.
[0089] Composition 8-3 comprised about 13.6 weight percent
cellulose propionate (Aldrich, Milwaukee, Wis.; Catalog #45,490-7),
about 43.2 weight percent isopropyl alcohol, and about 43.2 weight
percent 2-butanone.
4TABLE 4 IP Results For Banded Cigarettes. Dry band Composition IP
Pass (%)** weight (.mu.g)* Cellulose/DMAC/Lithium Chloride 100.0
104 (Composition 1-1)*** Cellulose/Water (Composition 8-1) 0.0 250
Cellulose/Water (Composition 8-1) 0.0 480 Cellulose/Water
(Composition 8-2) 100.0 910 Cellulose Propionate/Isopropyl
Alcohol/2- 37.5 150 Butanone (Composition 8-3) Cellulose
Propionate/Isopropyl Alcohol/2- 100.0 330 Butanone (Composition
8-3) *Polymer component; Average weight on 8 treated cigarettes
**NIST (#6) cotton duck IP test; 8 cigarettes studied See Example
1
[0090] Table 4 and FIG. 7 demonstrates that, as applied,
cellulose/DMAC/lithium chloride is a very efficient material for
forming a reduced IP smoking article. Cellulose when combined with
a self-association disrupter solvent system is more efficient than
cellulose suspended as particles in water (Composition 8-2).
Furthermore, cellulose/DMAC/lithium chloride was found to be more
efficient than the organic solvent soluble cellulose derivative
cellulose propionate (Composition 8-3). Applicants believe that
other polysaccharides combined with self-association disrupter
solvent systems will display efficient permeability reducing
properties.
[0091] FIG. 7 graphically illustrates that discrete areas on the
smoking article wrapper formed by the application of about 0.3
micrograms per square millimeter to about 1.2 micrograms per square
millimeter of substantially non-derivatized cellulose applied using
lithium chloride in dimethylacetamide (DMAC) and the like may give
an article with reduced IP properties. Those skilled in the art
will appreciate that application of a material amount in excess of
that required to give 100% effective IP reduction will also give
100% IP reduction.
[0092] Certain modifications and improvements will occur to those
skilled in the art upon a reading of the foregoing description. For
example, after treating the paper with a permeability reducing
substance, such as cellulose/DMAC/lithium chloride and the like,
the salts, e.g., lithium chloride, content may be reduced or
redistributed in paper by a variety of techniques known to those
skilled in the art such as application of water, and application of
water in conjunction with the application of blotting or suction.
Applicants believe that the reduction of the lithium chloride
content of cellulose/DMAC/lithium chloride (and the like) treated
paper will be useful for the manufacture of reduced IP smoking
articles. It should be understood that all such modifications and
improvements have been deleted herein for the sake of conciseness
and readability but are properly within the scope of the following
claims.
* * * * *
References