U.S. patent application number 12/183470 was filed with the patent office on 2009-02-05 for degradable cigarette filters.
This patent application is currently assigned to Philip Morris USA Inc.. Invention is credited to Shalva Gedevanishvili, Milton E. Parrish, Lixin L. Xue, Szu-Sung Yang.
Application Number | 20090032037 12/183470 |
Document ID | / |
Family ID | 40304985 |
Filed Date | 2009-02-05 |
United States Patent
Application |
20090032037 |
Kind Code |
A1 |
Xue; Lixin L. ; et
al. |
February 5, 2009 |
DEGRADABLE CIGARETTE FILTERS
Abstract
Biodegradable cigarette filters comprise shaped fiber of PHBV.
Included among these fiber shapes in cross section are Y, V, C,
Triad, 4-DG and JC shapes. The shaped fibers may include micro
cavities with adsorbents and/or flavorants in the cavities.
Inventors: |
Xue; Lixin L.; (Midlothian,
VA) ; Parrish; Milton E.; (Midlothian, VA) ;
Gedevanishvili; Shalva; (Richmond, VA) ; Yang;
Szu-Sung; (Richmond, VA) |
Correspondence
Address: |
CONNOLLY BOVE LODGE & HUTZ, LLP
P O BOX 2207
WILMINGTON
DE
19899
US
|
Assignee: |
Philip Morris USA Inc.
Richmond
VA
|
Family ID: |
40304985 |
Appl. No.: |
12/183470 |
Filed: |
July 31, 2008 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
60953296 |
Aug 1, 2007 |
|
|
|
Current U.S.
Class: |
131/332 |
Current CPC
Class: |
A24D 3/163 20130101;
A24D 3/068 20130101; A24D 3/064 20130101; A24D 3/08 20130101 |
Class at
Publication: |
131/332 |
International
Class: |
A24D 3/08 20060101
A24D003/08 |
Claims
1. A biodegradable cigarette filter comprising shaped fibers of
PHBV.
2. A biodegradable cigarette filter as in claim 1 wherein the
fibers have a Y shape in cross section.
3. A biodegradable cigarette filter as in claim 1 wherein the
fibers have a V shape in cross section.
4. A biodegradable cigarette filter as in claim 1 wherein the
fibers have a C shape in cross section.
5. A biodegradable cigarette filter as in claim 1 wherein the
fibers have a Triad shape in cross section.
6. A biodegradable cigarette filter as in claim 1 wherein the
fibers have a 4-DG shape in cross section.
7. A biodegradable cigarette filter as in claim 1 wherein the
fibers have a JC shape in cross section.
8. A biodegradable cigarette filter as in claim 1 wherein the
fibers include micro cavities.
9. A biodegradable cigarette filter as in claim 8 including
adsorbents in the micro cavities.
10. A biodegradable cigarette filter as in claim 9 wherein the
adsorbents include carbon.
11. A biodegradable cigarette filter as in claim 8 including
flavorants in the micro cavities.
12. A biodegradable cigarette filter as in claim 11 wherein the
flavorants include menthol.
Description
CROSS REFERENCE RELATED TO APPLICATION
[0001] The present application claims the benefit of provisional
application Ser. No. 60/953,296, filed Aug. 1, 2007, for all useful
purposes, and the specification and drawings thereof are included
herein by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to degradable cigarette
filters, and more particularly to shaped fibers made from
degradable materials and the use of such shaped fibers in cigarette
filters.
[0003] Conventional cigarette filter plugs are made of cellulose
acetate fibers bonded to each other by triacetin. After smoking,
the spent filters are sometimes discarded in the environment. The
cellulose acetate filaments therein tend to degrade slower than
tobacco and/or the paper parts of the cigarettes, often
contributing to the litter in the environment. To reduce such
litter, there is a need to replace cellulose acetate filaments in
cigarette filters with materials that degrade faster than cellulose
acetate in the environment. At the same time, there is also a need
to retain the filtration chemistry, smoke characteristics and
consumer acceptability from the cellulose acetate triacetin
systems.
SUMMARY OF THE INVENTION
[0004] Among the objects of the present invention is a cigarette
filter produced from biodegradable materials formed into fibers
with designed cross sectional shapes.
[0005] Another object of the present invention is a cigarette
filter of biodegradable shaped fibers with increased surface area
and reduced overall material per filter.
[0006] Still another object of the present invention is a cigarette
filter of biodegradable shaped fibers having micro cavities therein
for retaining flavorants and adsorbents for favor delivery and
selective filtration.
[0007] In accordance with the present invention, a biodegradable
cigarette filter comprises shaped fibers of PHBV. The fibers may
have designed shapes in cross section that include Y, V, C, Triad,
4-DG and JC shapes Moreover, the shaped fiber may include micro
cavities with adsorbents and/or flavorants in the cavities.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] Novel features and advantages of the present invention in
addition to those mentioned above will become readily apparent to
persons of ordinary skill in the art from a reading of the
following detailed description in conjunction with the accompanying
drawings wherein similar parts are identified by similar reference
characters and in which:
[0009] FIG. 1 is a cross sectional view of a shaped biodegradable
fiber having a Y shape;
[0010] FIG. 2 is a cross sectional view of a shaped biodegradable
fiber having a V shape;
[0011] FIG. 3 is a cross sectional view of a shaped biodegradable
fiber having a C shape;
[0012] FIG. 4 is a cross sectional view of a shaped biodegradable
fiber having a Triad shape;
[0013] FIG. 5 is a cross sectional view of a shaped biodegradable
fiber having a 4-DG shape; and
[0014] FIG. 6 is a cross sectional view of a shaped biodegradable
fiber having a JC shape.
DETAILED DESCRIPTION OF THE INVENTION
[0015] The cigarette filters of the present invention may be made
of sheets, films, fiber bands, yarns, or non-wovens from
biodegradable materials such as paper (wood pulps), wool, cellulose
acetate with lower acetylating levels, starch, and starch based
polymer composites, cotton, polyactic acid, polyvinyl alcohol,
polyhyroxyalkanoates, polyesters, polyesteramides,
polycaprolactones, un-stabilized polypropylene, micro-glass
materials, and their combinations. The biodegradable materials can
be spun into fibers by melt spinning, dry spinning, wet spinning,
electro spinning or any other known process into fibers.
[0016] For example, PHBV (Polyhydroxybutyrate-co-hydroxyvalerate)
and its blends with aliphatic aromatic polyester such as Ecoflex,
PBS (poly butylenes succinate), d-, 1-, and dl-PLA (polyactic acid)
and starch composites have been successfully spun into round cross
section fibers by melt spinning process. However, in order to
increase the surface area and reduce material use per filter, the
filter fibers herein have improved cross sectional shapes. These
shaped fibers are formed into filters and used in reduced litter
cigarettes.
[0017] The cross section of the fibers may be controlled by the
shapes of the die used in the spinning processes. As shown in FIGS.
1-6, the cross section of the fibers may be modified to Y, V, C,
Triad, 4-DG, or JC by using appropriate dies in the melt spinning
process. Other fiber cross sections that have been reported in the
literature such as those in U.S. Pat. No. 6,907,895 are included
herein by reference.
[0018] To process these shaped fibers into cigarette filters,
single or multi-strands of these shaped fibers from single or
multiple components may be drawn and crimped into tow bands, or the
strands of these shaped fibers made of faster degradable materials
can be combined with cellulose acetate fibers to form a joint tow
bands during the cigarette filter making process. Alternatively,
nonwovens from the above fibers can be produced from melt-blown,
spun bonded, needle punched/felt, wet-laid, air-laid and other
processes and then processed into cigarette filters by processes of
rolling, folding or shredding. Appropriate amounts of a
bonding/hardening agent may be applied onto the fibers in the
filters as needed for firmness and smoke subjective adjustment.
Adsorbents such as carbon granules and flavorants such as menthol
can be impregnated into the micro cavities of the shaped fibers as
well.
* * * * *