U.S. patent application number 17/282215 was filed with the patent office on 2021-10-28 for cooling element.
The applicant listed for this patent is Essentra Filter Products Development Co. Pte. Ltd.. Invention is credited to Michael GREGG, Paul MORRIS, Arief RAHMAN, Sudirman Widiarto WIDIARTO.
Application Number | 20210329966 17/282215 |
Document ID | / |
Family ID | 1000005755776 |
Filed Date | 2021-10-28 |
United States Patent
Application |
20210329966 |
Kind Code |
A1 |
MORRIS; Paul ; et
al. |
October 28, 2021 |
COOLING ELEMENT
Abstract
The present invention provides a cooling element (4) with a
longitudinally extending core of cellulose acetate material having
a profiled outer surface including a plurality of grooves or
channels (9) which extend the full length of the core for use with
a smoking article such as a tobacco heated product (1) or
heat-not-burn product (1).
Inventors: |
MORRIS; Paul; (Singapore,
SG) ; RAHMAN; Arief; (East Java, ID) ;
WIDIARTO; Sudirman Widiarto; (Sidoarjo, Jawa Timur, ID)
; GREGG; Michael; (Sidoarjo, ID) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Essentra Filter Products Development Co. Pte. Ltd. |
Singapore |
|
SG |
|
|
Family ID: |
1000005755776 |
Appl. No.: |
17/282215 |
Filed: |
October 7, 2019 |
PCT Filed: |
October 7, 2019 |
PCT NO: |
PCT/EP2019/077043 |
371 Date: |
April 1, 2021 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A24D 3/10 20130101; A24D
3/067 20130101; A24D 3/17 20200101; A24D 1/20 20200101; A24D 3/04
20130101 |
International
Class: |
A24D 3/06 20060101
A24D003/06; A24D 1/20 20060101 A24D001/20; A24D 3/10 20060101
A24D003/10; A24D 3/17 20060101 A24D003/17; A24D 3/04 20060101
A24D003/04 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 8, 2018 |
GB |
1816367.5 |
Feb 28, 2019 |
GB |
1902729.1 |
Claims
1. A cooling element comprising a longitudinally extending core of
cellulose acetate material; the longitudinally extending core of
cellulose acetate material having a profiled outer surface
including a plurality of grooves or channels of depth 0.5 to 2.6 mm
which extend the full length of the core.
2. A cooling element according to claim 1 further comprising an
outer wrapper engaged around the longitudinally extending core
which defines with the profiled outer surface of the core a
plurality of covered grooves or channels of depth 0.5 to 2.6 mm
which extend the full length of the tubular core.
3. A cooling element comprising a longitudinally extending tubular
core of cellulose acetate material; the longitudinally extending
tubular core of cellulose acetate material having an inner surface
which defines a bore extending longitudinally through the full
length of the tubular core, and a profiled outer surface including
a plurality of grooves or channels of depth 0.5 to 2.6 mm which
extend the full length of the tubular core.
4. A cooling element according to claim 3 further comprising an
outer wrapper engaged around the longitudinally extending tubular
core which defines with the profiled outer surface of the core a
plurality of covered grooves or channels of depth 0.5 to 2.6 mm
which extend the full length of the tubular core.
5. A cooling element according claim 1 wherein the profiled outer
surface defines 3 to 10, for example 3 to 7, for example 4 to 6,
for example 5, channels of depth between 0.5 mm and 2.6 mm.
6. A cooling element according to claim 1 wherein the depth of each
channel is from 0.5 to 2.5 mm, for example 0.8 to 2.2 mm, for
example 1.30 to 2.1 mm, preferably from 1.35 to 2 mm, for example
1.4 to 1.9 mm.
7. A cooling element according to claim 1 wherein the length of the
cooling element is from 5 to 35 mm, e.g. 10 to 2 5mm, e.g. 15 to 20
mm, e.g. 18 mm.
8. A cooling element according to claim 1 wherein the circumference
of the cooling element is from 12 to 30 mm, e.g. 15 to 28 mm, more
preferably 17 to 25 mm.
9. A cooling element according to claim 1 wherein the cooling
element is thermoformed from cellulose acetate.
10. (canceled)
11. A cooling element for a tobacco heated product and/or HNB
product comprising a longitudinally extending tubular core of
cellulose acetate material; the longitudinally extending tubular
core of cellulose acetate material having an inner surface which
defines a bore extending longitudinally through the full length of
the tubular core, and a profiled outer surface including a
plurality of grooves or channels which extend the full length of
the tubular core.
12. A cooling element for a tobacco heated product and/or HNB
product comprising a longitudinally extending core of cellulose
acetate material; the longitudinally extending core of cellulose
acetate material having a profiled outer surface including a
plurality of grooves or channels which extend the full length of
the tubular core.
13. A smoking article (e.g. Tobacco heating product, HNB product)
comprising a cooling element according to claim 1.
14. A smoking article comprising: a hollow tubular element, the
hollow tubular element having bore of diameter A; and, abutted
thereto, a cooling element comprising a longitudinally extending
tubular core of cellulose acetate material; the longitudinally
extending tubular core of cellulose acetate material having an
inner surface which defines a bore extending longitudinally through
the full length of the tubular core, and a profiled outer surface
including a plurality of grooves or channels of depth 0.5 to 2.6 mm
which extend the full length of the tubular core; wherein diameter
A is sufficiently large such that a part of the bore of the hollow
tubular element is in register with a part of the bore of the
cooling element, and a part of the bore of the tubular element is
in register with at least a part of a (or preferably each) groove
(channel).
15. A smoking article comprising: a hollow tubular element, the
hollow tubular element having bore of diameter A; and, abutted
thereto, a cooling element comprising a longitudinally extending
core of cellulose acetate material; the longitudinally extending
core of cellulose acetate material having a profiled outer surface
including a plurality of grooves or channels of depth 0.5 to 2.6 mm
which extend the full length of the core; wherein diameter A is
sufficiently large such that a part of the bore of the tubular
element is in register with at least a part of a (or preferably
each) groove (channel).
16. A smoking article according to claim 14 where the hollow
tubular element is formed from cellulose acetate.
17. A smoking article according to claim 14 where the hollow
tubular element has walls of thickness 0.3 mm to 5.5 mm, for
example 0.4 mm to 5.5 mm, for example 0.4 to 1.0 mm or 1.0 to 5.5
mm.
18-20. (canceled)
Description
[0001] The present invention provides a cooling element for use
with a smoking article such as a tobacco heated product or
heat-not-burn product.
[0002] Tobacco heated products or heat-not-burn (HNB) products are
well known. The idea of a tobacco heated product is that the
tobacco is heated to a specific temperature (such as 350.degree.
C.) without burning. This delivers a vapour containing nicotine but
it is believed that heating without burning avoids creation of
combustion products that are harmful to the consumer.
[0003] Tobacco heating products (HNB products) may include a plug
of modified tobacco and other mouthpiece elements which are wrapped
in a paper plugwrap so as to provide a cigarette-like appearance.
In one such product a reconstituted tobacco plug, a wrapped hollow
acetate tube, a wrapped plug of PLA [poly(lactic acid)] and a
conventional wrapped acetate segment are wrapped in a white paper.
The product may then be inserted into a heating element which heats
the tobacco so the product can then be "smoked" by the consumer.
The function of the "filter" in these products is very different
from that of a cigarette filter; the main functions are to provide
the look and feel of a cigarette and also to cool the smoke down to
an acceptable temperature for the consumer. In the product
described above it is the PLA section which performs the
significant cooling function.
[0004] The PLA segment has drawbacks in terms of availability,
manufacturing capability, filtration properties (particularly in
relation to phenols), sensation, firmness, biodegradability and
appearance.
[0005] According to the present invention in a first aspect there
is provided a cooling element (e.g. a cooling element for a tobacco
heated product and/or HNB product) comprising a longitudinally
extending core of (e.g. thermoformed) cellulose acetate material;
the longitudinally extending core of cellulose acetate material
having a profiled outer surface including a plurality of (e.g.
longitudinally extending) (e.g. C-shaped or U-shaped) grooves or
channels of depth (e.g. maximum depth) 0.5 to 2.6 mm which extend
the full length of the (outer surface of the) core.
[0006] The cooling element may further comprise an outer wrapper
engaged around the longitudinally extending core which defines with
the profiled outer surface of the core a plurality of covered (e.g.
longitudinally extending) grooves or channels of depth (e.g.
maximum depth) 0.5 to 2.6 mm which extend the full length of the
(outer surface of the) core. The outer wrapper may be a paper (e.g.
plugwrap), preferably a paper (e.g. plugwrap) of basis weight 40 to
160 gsm, for example a paper (e.g. plugwrap) of basis weight 70 to
150 gsm, for example a paper (e.g. plugwrap) of basis weight 70 to
140 gsm.
[0007] The longitudinally extending core may be a longitudinally
extending tubular core of cellulose acetate material having an
inner surface which defines a bore (or hole) extending
longitudinally through the full length of the tubular core, and a
profiled outer surface including a plurality of (e.g.
longitudinally extending) (e.g. C-shaped or U-shaped) grooves or
channels of depth (e.g. maximum depth) 0.5 to 2.6 mm which extend
the full length of the (outer surface of the) tubular core.
[0008] According to the present invention in an aspect there is
provided a cooling element (e.g. a cooling element for a tobacco
heated product and/or HNB product) comprising a longitudinally
extending tubular core of (e.g. thermoformed) cellulose acetate
material; the longitudinally extending tubular core of cellulose
acetate material having an inner surface which defines a bore (or
hole) extending longitudinally through the full length of the
tubular core, and a profiled outer surface including a plurality of
(e.g. longitudinally extending) (e.g. U-shaped) grooves or channels
of depth (e.g. maximum depth) 0.5 to 2.6 mm which extend the full
length of the (outer surface of the) tubular core.
[0009] The cooling element may further comprise an outer wrapper
engaged around the longitudinally extending tubular core which
defines with the profiled outer surface of the core a plurality of
covered (e.g. longitudinally extending) grooves or channels of
depth (e.g. maximum depth) 0.5 to 2.6 mm which extend the full
length of the (outer surface of the) tubular core. The outer
wrapper may be a paper (e.g. plugwrap), preferably a paper (e.g.
plugwrap) of basis weight 40 to 160 gsm, for example a paper (e.g.
plugwrap) of basis weight 70 to 150 gsm, for example a paper (e.g.
plugwrap) of basis weight 70 to 140 gsm.
[0010] The applicants have found that a cellulose acetate cooling
element may provide appropriate cooling, while providing
satisfactory appearance and feel to the consumer.
[0011] In some examples, the cooling element of the invention has
zero, or substantially zero, tobacco smoke filtering effect. In
other examples, the cooling element of the invention may have a
tobacco smoke filtering effect.
[0012] Preferably the profiled outer surface defines 3 to 10, for
example 3 to 7, for example 4 to 6, for example 5, (e.g.
longitudinally extending) channels of depth 0.5 mm to 2.6 mm. The
channels are preferably longitudinally extending grooves or
channels which extend the full length of the (outer surface of the)
(e.g. tubular) core. However, they may be helical, although still
extending the full length of the (outer surface of the) (e.g.
tubular) core. The depth (e.g. maximum depth) of each channel is
from 0.5 to 2.5 mm, for example 0.8 to 2.2 mm, for example 1.30 to
2.1 mm, preferably from 1.35 to 2 mm, for example 1.4 to 1.9 mm.
The width (e.g. maximum width) of each channel is from 1.0 to 3.0
mm, for example 1.30 to 2.1 mm, preferably from 1.35 to 2 mm, for
example 1.4 to 1.9 mm.
[0013] Preferably the length of the cooling element is from 5 to 35
mm, for example from 10 to 25 mm, e.g. 15 to 20 mm, e.g. 18 mm.
[0014] Preferably the circumference of the cooling element is from
12 to 30 mm, e.g. 15 to 28 mm, more preferably 17 to 25 mm, e.g. 18
to 25 mm, e.g. 20 to 24 mm, e.g. 22 to 24 mm, e.g. 23.2 mm. The
term "circumference", when used with reference to the
grooved/channeled cooling element, refers to an imaginary circular
line which runs around the outer (circular) part of the cooling
element but ignores the channels.
[0015] Preferably the longitudinally extending core of cellulose
acetate material is of uniform axial cross section.
[0016] Preferably the longitudinally extending tubular core (if the
core is tubular) of cellulose acetate material is of uniform axial
cross section. The bore is preferably circular but may be of a
different shape [circular, semi-circular (D-shaped), square,
triangular, hollow star shaped, trilobal, pentagonal or cog-shaped
cross-section, or of a cross-section in the shape of a logo or
other pattern].
[0017] The cooling element may include more than one bore.
[0018] The cooling element may be thermoformed from cellulose
acetate by methods well known in the art. The cellulose acetate may
further comprise plasticiser (e.g. triacetin, triethyleneglycol
diacetate (TEGDA) or polyethylene glycol (PEG) or other
plasticiser, or a mixture of plasticisers).
[0019] The applicants have surprisingly found that a cooling
element according to this aspect of the invention, together with
the other components of the mouthpiece, can provide effective
cooling of the vapour. This is particularly surprising given the
conventional wisdom that cellulose acetate segments are not able to
perform this function.
[0020] According to the present invention there is provided a
smoking article (e.g. Tobacco heating product, HNB product)
comprising a cooling element as herein described and claimed
below.
[0021] It will be appreciated that the cooling element may be used
in any multi-segment filter or consumable. The filter construction
could be two, three, four or more segments. The filter may be
attached to a tobacco rod (which can be made from any form of
tobacco (including reconstituted). The filter may include other
segments that include capsules, carbon, CPS, tubes, acetate, paper,
menthol etc.
[0022] According to the present invention in a further aspect there
is provided a smoking article (e.g. Tobacco heating product, HNB
product) comprising: a hollow tubular element (formed from e.g.
cellulose acetate material), the hollow tubular element having bore
of diameter A; and, abutted thereto, a cooling element comprising a
longitudinally extending core of (e.g. thermoformed) cellulose
acetate material; the longitudinally extending core of cellulose
acetate material having a profiled outer surface including a
plurality of (e.g. longitudinally extending) (e.g. C-shaped or
U-shaped) grooves or channels of depth (e.g. maximum depth) 0.5 to
2.6 mm which extend the full length of the (outer surface of the)
core; wherein diameter A is sufficiently large that a part of the
bore of the tubular element is in register with at least a part of
a (preferably, each) groove (channel).
[0023] The smoking article may further comprise an outer wrapper
engaged around the hollow tubular element having bore of diameter A
and the cooling element. This defines, with the profiled outer
surface of the core of the cooling element, a plurality of covered
(e.g. longitudinally extending) grooves or channels of depth 0.5 to
2.6 mm which extend the full length of the (outer surface of the)
tubular core of the cooling element. The outer wrapper may be a
paper (e.g. plugwrap), preferably a paper (e.g. plugwrap) of basis
weight 40 to 160 gsm, for example a paper (e.g. plugwrap) of basis
weight 70 to 150 gsm, for example a paper (e.g. plugwrap) of basis
weight 70 to 140 gsm.
[0024] According to the present invention in a further aspect there
is provided a smoking article (e.g. Tobacco heating product, HNB
product) comprising: a hollow tubular element (formed from e.g.
cellulose acetate material), the hollow tubular element having bore
of diameter A; and, abutted thereto, a cooling element comprising a
longitudinally extending tubular core of (e.g. thermoformed)
cellulose acetate material; the longitudinally extending tubular
core of cellulose acetate material having an inner surface which
defines a bore extending longitudinally through the full length of
the tubular core, and a profiled outer surface including a
plurality of (e.g. longitudinally extending) (e.g. C-shaped or
U-shaped) grooves or channels of depth (e.g. maximum depth) 0.5 to
2.6 mm which extend the full length of the (outer surface of the)
tubular core; wherein diameter A is sufficiently large such that a
part of the bore of the hollow tubular element is in register with
(e.g. a part of) the bore of the cooling element, and a part of the
bore of the tubular element is in register with at least a part of
a (preferably, each) groove (channel).
[0025] The smoking article may further comprise an outer wrapper
engaged around the hollow tubular element having bore of diameter A
and the cooling element. This defines, with the profiled outer
surface of the core of the cooling element, a plurality of covered
(e.g. longitudinally extending) grooves or channels of depth 0.5 to
2.6 mm which extend the full length of the (outer surface of the)
tubular core of the cooling element. The outer wrapper may be a
paper (e.g. plugwrap), preferably a paper (e.g. plugwrap) of basis
weight 40 to 160 gsm, for example a paper (e.g. plugwrap) of basis
weight 70 to 150 gsm, for example a paper (e.g. plugwrap) of basis
weight 70 to 140 gsm.
[0026] Preferably the profiled outer surface of the cooling element
defines 3 to 10, for example 3 to 7, for example 4 to 6, for
example 5, (e.g. longitudinally extending) channels of depth (e.g.
maximum depth) from 0.5 mm to 2.6 mm. The channels are preferably
longitudinally extending grooves or channels which extend the full
length of the (outer surface of the) (e.g. tubular) core. However,
they may be helical, although still extending the full length of
the (outer surface of the) (e.g. tubular) core.
[0027] The depth (e.g. maximum depth) of each channel is from 0.5
to 2.5 mm, for example 0.8 to 2.2 mm, for example 1.30 to 2.1 mm,
preferably from 1.35 to 2 mm, for example 1.4 to 1.9 mm. The width
(e.g. maximum width) of each channel is from 1.0 to 3.0 mm, for
example 1.30 to 2.1 mm, preferably from 1.35 to 2 mm, for example
1.4 to 1.9 mm.
[0028] Preferably the length of the cooling element is from 5 to 35
mm, for example from 10 to 25 mm, e.g. 15 to 20 mm, e.g. 18 mm.
[0029] Preferably the circumference of the cooling element is from
12 to 30 mm, e.g. 15 to 28 mm, more preferably 17 to 25 mm, e.g. 18
to 25 mm, e.g. 20 to 24 mm, e.g. 22 to 24 mm, e.g. 23.2 mm. The
term "circumference", when used with reference to the
grooved/channeled cooling element, refers to an imaginary circular
line which runs around the outer (circular) part of the cooling
element but ignores the channels.
[0030] Preferably the bore of the cooling element (if present) has
diameter from 1 to 5 mm, e.g. 1 to 4 mm, e.g. 2 to 4 mm.
[0031] The circumference of the hollow tubular element is from 12
to 30 mm, e.g. 15 to 28 mm, e.g. 18 to 25 mm, preferably 20 to 24
mm, more preferably 22 to 24 mm, e.g. 23.2 mm. Preferably the
circumference of the hollow tubular element is the same as that of
the cooling element.
[0032] The hollow tubular element may have walls of thickness 0.3
mm to 5.5 mm, for example 0.4 to 5.5 mm, for example 0.5 to 2.5 mm,
preferably 1 to 2 mm. The hollow tubular element may have walls of
thickness 0.4 to 1.0 mm. The hollow tubular element may have walls
of thickness 1.0 to 5.5 mm.
[0033] Preferably the hollow tubular element has bore of diameter A
which is from 3 to 10 mm, e.g. 4 to 6 mm, e.g. 5 mm.
[0034] Preferably the length of the hollow tubular element is from
5 to 25 mm, for example from 5 to 20 mm, e.g. 6 to 10 mm, e.g. 7
mm.
[0035] The applicants have surprisingly found that a cooling
element according to this aspect of the invention, together with
the other components of the mouthpiece, can provide effective
cooling of the vapour. This is particularly surprising given the
conventional wisdom that cellulose acetate segments are not able to
perform this function. It is believed that the interaction between
the hollow acetate tube and the cooling element provides a variety
of pathways for the vapour to flow through the cellulose acetate
cooling element which provides adequate cooling.
[0036] According to the present invention in a further aspect there
is provided a cooling element (e.g. a cooling element for a tobacco
heated product and/or HNB product) comprising a longitudinally
extending tubular core of (e.g. thermoformed) cellulose acetate
material; the longitudinally extending tubular core of cellulose
acetate material having an inner surface which defines a bore (or
hole) extending longitudinally through the full length of the
tubular core, and a profiled outer surface including a plurality of
(e.g. longitudinally extending) (e.g. C-shaped or U-shaped) grooves
or channels which extend the full length of the (outer surface of
the) tubular core. Preferably the grooves or channels are of depth
(e.g. maximum depth) 1.30 to 2.6 mm.
[0037] According to the present invention in a further aspect there
is provided a cooling element (e.g. a cooling element for a tobacco
heated product and/or HNB product) comprising a longitudinally
extending core of (e.g. thermoformed) cellulose acetate material;
the longitudinally extending core of cellulose acetate material
having a profiled outer surface including a plurality of (e.g.
longitudinally extending) (e.g. C-shaped or U-shaped) grooves or
channels which extend the full length of the (outer surface of the)
core. Preferably the grooves or channels are of depth (e.g. maximum
depth) 1.30 to 2.6 mm.
[0038] According to the present invention in a further aspect there
is provided the use, in a tobacco heated product and/or HNB
product, of a cooling element comprising a longitudinally extending
tubular core of (e.g. thermoformed) cellulose acetate material; the
longitudinally extending tubular core of cellulose acetate material
having an inner surface which defines a bore (or hole) extending
longitudinally through the full length of the tubular core, and a
profiled outer surface including a plurality of (e.g.
longitudinally extending) (e.g. U-shaped) grooves or channels which
extend the full length of the (outer surface of the) tubular core.
Preferably the grooves or channels are of depth (e.g. maximum
depth) 1.30 to 2.6 mm.
[0039] According to the present invention in a further aspect there
is provided the use, in a tobacco heated product and/or HNB
product, of a cooling element comprising a longitudinally extending
core of (e.g. thermoformed) cellulose acetate material; the
longitudinally extending core of cellulose acetate material having
a profiled outer surface including a plurality of (e.g.
longitudinally extending) (e.g. C-shaped or U-shaped) grooves or
channels which extend the full length of the (outer surface of the)
core. Preferably the grooves or channels are of depth (e.g. maximum
depth) 1.30 to 2.6 mm.
[0040] The present invention will now be discussed in further
detail with reference to the attached FIG. 1 which shows (not to
scale) a longitudinal cross section of a tobacco heated product
according to the invention which includes a cooling element
according to the invention;
[0041] FIG. 2 which shows (not to scale) an axial cross section
(along line X-X of FIG. 1) of the cooling element of the invention
shown in FIG. 1;
[0042] FIG. 3 which shows (not to scale) an axial cross section
(along line X-X of FIG. 1) of a different cooling element to that
of FIG. 2, which is also of the invention, which could be used in
the tobacco heated product according to the invention shown in FIG.
1; and
[0043] FIG. 4 which compares pressure drop (mmWG) of cooling
elements of the invention (B, C, D, E) with a conventional PLA
cooling element (A).
[0044] FIG. 1 shows a longitudinal cross section along the centre
line of a cylindrical HNB product 1. Cylindrical HNB product 1
comprises four segments: a cylindrical plug of reconstituted
tobacco 2; a cylindrical hollow acetate tube 3; a cooling element
4; and a cylindrical plug of cellulose acetate tow 5.
[0045] Plug 2 of reconstituted tobacco 2 is 12 mm long and has
circumference 23.2 mm, and forms one end of the HNB product 1. Such
plugs are well known in the art. This plug is heated in use by a
heating device as is well known in the art. The plug 2 of
reconstituted tobacco material is abutted at one end to a 7 mm long
cylindrical hollow acetate tube 3, also of circumference 23.2 mm,
and wall thickness 1.3 mm. Tube 3 has a cylindrical bore 3a. The
end of the cylindrical hollow acetate tube 3 opposite to plug 2 is
abutted to cooling element 4. Hollow acetate tubes and their
manufacture are well known in the art of tobacco smoke filters (see
e.g. GB970817, e.g. FIG. 7 embodiment and associated
discussion).
[0046] Cooling element 4 comprises a longitudinally extending
tubular core of thermoformed cellulose acetate material of length
18 mm. The longitudinally extending tubular core of cellulose
acetate material is thermoformed with an inner surface which
defines a bore (or hole) 8 of diameter 2 mm extending
longitudinally through the full length of the tubular core, and a
profiled outer surface including five longitudinally extending
channels or grooves 9 of generally shallow U-shaped cross section
with maximum depth 1.80 mm and width 1.5 mm which extend the full
length of the tubular core. The five channels 9 are spaced
equidistantly around the perimeter of the profiled outer surface
(as can be seen from FIG. 2). The longitudinally extending tubular
core of cellulose acetate material is of uniform axial cross
section, as shown in FIG. 2. It will be appreciated that the cross
section of the cooling element 4 can be considered to be generally
annular with five shallow U-shaped grooves or channels 9 disposed
equidistantly about its perimeter. The term "circumference", when
used with reference to the grooved/channeled cooling element,
refers to an imaginary circular line which runs around the outer
(circular) part of the cooling element but ignores the channels;
thus the circumference of element is approximately 23.2 mm such
that it is generally in register with the outer surface of the
hollow acetate tube 3 (which has similar circumference) to which it
abuts. Cooling element 4 is thermoformed using a steam bonded
process, as is well known in the art. Cellulose acetate tow is
processed and then fed into a steam die which has a lead in but
tapers down to the size and shape of cross section that is required
(e.g. the cross section shown in FIG. 2). As the tow passes through
the die it is formed and partially cured to form the shape
required. There may be more than one steam die which may be
followed by a number of drying stations which blow hot air onto the
rod to rid it of any excess steam/moisture. The rod is then fed
onto a garniture where it is pulled through and cut to the desired
length.
[0047] Cylindrical plug 5 is of length 8 mm and circumference 23.2
mm and comprises a rod of cellulose acetate tow with plug wrap
disposed there around. Such "wrapped acetate" plugs are well known
in the art of tobacco smoke filters. Plug 5 is abutted to the
opposite end of cooling element 4 to hollow acetate tube 3 such
that cooling element 4 is between plug 5 and hollow acetate tube
3.
[0048] The cylindrical plug of reconstituted tobacco 2, cylindrical
hollow acetate tube 3, cooling element 4, and a cylindrical plug of
cellulose acetate tow 5 are further wrapped with a plug wrap (not
shown) of conventional plugwrap paper (that is well known in the
art) which surrounds the plug 2, tube 3, element 4 and plug 5 and
which provides an external appearance similar to a cigarette.
[0049] The diameter of bore 3a (which may be referred to herein as
dimension "A") is sufficiently large such that a part of the bore
3a of the tubular element 3 is in register with (e.g. a part of)
the bore 8 of the cooling element, and a part of the bore of the
tubular element is in register with at least a part (i.e. the
lowest extremities) of each groove (channel) 9. It will be
therefore be appreciated that the external grooves or channels 9 of
the cooling element 4, as well as the central bore 8, partially
overlap with the wider bore 3a of the hollow acetate tube 3. During
use, hot vapour from the plug of tobacco (which is heated in the
conventional manner) is drawn through the bore 3a of the hollow
acetate tube 3 and into the bore 8 and channels 9 of the cooling
element 4, and then on into and through the final acetate plug 5 to
the smoker's mouth. It is believed that this drawing of the hot
vapour through both the bore 8 and channels 9 of the cooling
element 4 provides adequate cooling, an effect which is not
expected from cellulose acetate material.
[0050] It will be appreciated that the hollow acetate tube, wrapped
acetate segment, and cooling element may be made by methods well
known in the art.
[0051] FIG. 3 shows (not to scale) an axial cross section (along
line X-X of FIG. 1) of a different cooling element 40', also of the
invention, which could be used in the tobacco heated product
according to the invention shown in FIG. 1. It will be appreciated
that heating element 40' may be used in place of element 4 in the
tobacco heated product according to the invention shown in FIG.
1.
[0052] Cooling element 40' comprises a longitudinally extending
core of thermoformed cellulose acetate material of length 18 mm.
The longitudinally extending core of cellulose acetate material is
thermoformed with a profiled outer surface including five
longitudinally extending channels or grooves 90' of generally
shallow U-shaped cross section with maximum depth 1.80 mm and width
1.5 mm which extend the full length of the core. The five channels
90' are spaced equidistantly around the perimeter of the profiled
outer surface (as can be seen from FIG. 3). The longitudinally
extending core of cellulose acetate material is of uniform axial
cross section, as shown in FIG. 3. It will be appreciated that the
cross section of the cooling element 40' can be considered to be
generally circular with five shallow U-shaped grooves or channels
90' disposed equidistantly about its perimeter. The term
"circumference", when used with reference to the grooved/channeled
cooling element, refers to an imaginary circular line which runs
around the outer (circular) part of the cooling element but ignores
the channels; thus the circumference of element 40' is
approximately 23.2 mm such that it is generally in register with
the outer surface of the hollow acetate tube 3 shown in FIG. 1
(which has similar circumference) to which it abuts if cooling
element 40' is used in place of cooling element 4 in FIG. 1.
Cooling element 40' is thermoformed using a steam bonded process,
as is well known in the art. Cellulose acetate tow is processed and
then fed into a steam die which has a lead in but tapers down to
the size and shape of cross section that is required (e.g. the
cross section shown in FIG. 3). As the tow passes through the die
it is formed and partially cured to form the shape required. There
may be more than one steam die which may be followed by a number of
drying stations which blow hot air onto the rod to rid it of any
excess steam/moisture. The rod is then fed onto a garniture where
it is pulled through and cut to the desired length.
[0053] If the cooling element of FIG. 3 is used in the product of
claim 1, it will be appreciated that the diameter of bore 3a (which
may be referred to herein as dimension "A") is sufficiently large
such that a part of the bore of the tubular element is in register
with at least a part (i.e. the lowest extremities) of each groove
(channel) 90'. It will be therefore be appreciated that the
external grooves or channels 90' of the cooling element 40'
partially overlap with the bore 3a of the hollow acetate tube 3.
During use, hot vapour from the plug of tobacco (which is heated in
the conventional manner) is drawn through the bore 3a of the hollow
acetate tube 3 and into the channels 90' of the cooling element
40', and then on into and through the final acetate plug 5 to the
smoker's mouth. The cooling element 40' provides adequate cooling,
an effect which is not expected from cellulose acetate
material.
EXPERIMENT
[0054] Cooling elements of the invention (B, C, D, E) were made.
Cooling elements B and C have similar cross section to that shown
in FIG. 3, with no central hole or bore. Cooling elements B and C
thus have generally circular cross section of circumference 22.30
mm and 5 channels of depth 1.2 mm. Cooling elements D and E are as
shown in FIG. 2, including a central bore. Cooling elements D and E
also have generally circular cross section of circumference 22.30
mm and 5 channels of depth 1.2 mm, but include a central bore of
diameter 1.2 mm. Cooling elements B, C, D and E were tested against
a conventional PLA cooling element (A) in a HNB product.
[0055] Five HNB products as shown in FIG. 1 were assembled for
testing, each including one of cooling elements of the invention B,
C, D E or comparative example A (known PLA product). Cooling
elements A, C and E were used with a hollow acetate tube (element 3
in FIG. 1) of circumference 22.30 mm and wall thickness 1.3 mm.
Cooling elements B and D were used with a "thin walled tube (TWT)"
hollow acetate tube (element 3 in FIG. 1) of circumference 22.30 mm
and wall thickness 0.8 mm.
[0056] FIG. 4 compares pressure drop (mmWG) associated with cooling
elements of the invention (B, C, D, E) and conventional PLA cooling
element (A). This shows that the profiles are similar, indicating
that the cooling elements of the invention are an excellent heat
sink in a THP product and are suitable as a replacement for PLA.
The cooling elements of the invention may therefore provide a
biodegradable alternative to the known PLA cooling elements. It can
be seen that B and C (no central bore) are closer in performance to
PLA, indicating they perform better than D and E in this test.
* * * * *