BRPI0718607A2 - SMOKING ARTICLE WITH A FLOW RESTRICTOR. - Google Patents

Description

Report of the Invention Patent for "SMOKING ARTICLE WITH A FLOW RESTRICTOR".

Background

Hitherto, cigarettes with high levels of ventilation have usually had unacceptably low levels of drag resistance (RTD) unless countermeasures are taken to make up for RTD deficiency. In the past, high density cellulose acetate filter segments have been used to address the deficiency. However, such filter segments tended to reduce tar distribution (FTC) with little or no effect on the gaseous phase components of tobacco mainstream smoke such as carbon monoxide (CO) and carbon dioxide. nitrogen oxide (NO). This solution tends to worsen the CO-to-tar (FTC) ratios in lower-distribution (tar-tar) cigarettes.

Ventilation has a desirable attribute where, when operating alone, it will reduce both the particulate phase and the gaseous phase of mainstream smoke. Highly ventilated cigarettes, however, have disadvantages in RTD as previously discussed.

Brief Description of the Drawings

Figure 1 is a side view of a smoker article constructed according to a preferred embodiment in which the filter tip paper has been partially unfolded to reveal internal filter components.

Figures 2 and 3 are side views of smoker articles with a partially unrolled tip paper to reveal filter components of other embodiments.

Figure 4 is a side view of a smoking article with the

partially unwound tip paper to reveal filter components that include a flow restriction filter segment that has end-to-end symmetry.

Figures 5 and 6 are side views of smoker's articles with partially unwrapped tip paper to reveal filter components of other embodiments.

Figure 7 illustrates a process by which currently disclosed filter rods are formed and inserted into smoker articles. Detailed Description of Preferred Modalities

Currently disclosed embodiments provide the benefit of a highly ventilated smoker article with desired amounts of drag resistance and / or provisions to facilitate high speed cigarette manufacture in conventional cigarette manufacturing equipment.

Referring to Figure 1, a preferred embodiment provides a smoker's article 10 comprising a tobacco rod 12 and a filter 14 connected to the tobacco rod 12 by means of a 10 tip paper 16. Preferably the filter 14 comprises a first filter segment 18 in an upstream portion 20 of filter 14, a nozzle filter segment 22 in the downstream end portion 24 of filter 14 and a flow restriction filter segment 26 located between the first and second nozzle filter segments 18 and 22. In this embodiment, filter segments 15 18 and 22 are low particulate performance filter segments, preferably constructed of 8.0 denier cellulose acetate bundle and denier total 35,000. In this embodiment, a relatively short flow restriction filter segment 26 (hereinafter the restricting disk) adjacent the first upstream filter plug 18 of a length of approximately 3 mm to 10 mm, more preferably approximately 3 mm, is included. up to 7 mm in length. In this embodiment a cavity 46 within the filter 14 is defined at least in part by a cylindrical tubular filter segment 48. Preferably the cavity 46 extends from the nozzle filter 22 to the venting zone 40 and preferably after zone 40 to flow restriction 30. Tubular filter segment 48 is preferably constructed of a relatively heavy filter pad, paper or other material such as cellulose acetate.

In this embodiment, the vent zone 40 comprises a plurality of vent holes extending through the tip paper 16 and through the tubular filter segment 48. This arrangement facilitates the use of inline laser drilling techniques. to provide vent holes during the manufacture of the smoker article 10.

Referring to Figure 2, another embodiment provides a smoking article comprising a tobacco rod and a filter connected to the tobacco rod by means of a tip paper. Preferably the filter comprises a first filter segment 18 constructed of cellulose acetate beam in an upstream portion of the filter, a nozzle filter segment 22 constructed of cellulose acetate beam in an extreme downstream portion of the filter. and a restricting disk 26 situated between the first and nozzle filter segments 18 and 22. In this embodiment the cavity 10 of 46 within the filter is defined at least in part by a preferably coiled coiled paper tube 48 extending across the entire length of the filter is strong enough to be self-supporting, yet thin enough to accommodate inline laser drilling. The outer ring of the restrictor disk preferably has a sliding fit with the inner surface 15 of the paper tube 48. Preferably the cavity 46 extends from the nozzle filter 22 to the vent zone 40 and preferably after the zone 40 to flow restriction 30. Pipe 48 may be made using other materials or other forming techniques such as extruding the pipe or forming a pipe with a longitudinal seam.

Referring to Figure 3, another embodiment provides

a smoker's article comprising a tobacco rod and a filter connected to the tobacco rod by a tip paper. Preferably, the filter comprises a first filter segment 19 constructed of carbon over beam in an upstream portion of the filter, a second filter segment 18 constructed of cellulose acetate beam downstream of the first filter segment 19, a nozzle filter segment 22 constructed of cellulose acetate beam at an end downstream of the filter and a restrictor disk 26 situated between the second and nozzle filter segments 18 and 22. In this embodiment the outer ring of the restrictor disk 26 is preferably slightly tapered to facilitate buffering of the restrictor disc 28 along the tube 48 from left to right. Preferably the cavity 46 extends from the nozzle filter 22 to the ventilation zone 40 and preferably beyond there to the flow restriction 30.

Referring to Figure 4, another embodiment provides a smoking article comprising a tobacco rod and a filter connected to the tobacco rod by means of a tip paper. Preferably the filter comprises a first filter segment 18 constructed of carbon over beam in a portion upstream of the filter, a second filter segment 18 constructed of cellulose acetate beam downstream of the first filter segment 19, a filter segment 18. nozzle filter 22 constructed of cellulose acetate beam at an end downstream of the filter and a flow restriction filter comprising a restricting disc 26 having a flow restriction hole 30 situated between the second filter segment 18 and the nozzle filter segment 22. In this embodiment the restrictor disk 26 is preferably symmetrical or has end-to-end symmetry. Preferably the cavity 46 extends from the nozzle filter 22 to the ventilation zone 40 and preferably thereafter to the flow restriction hole 30.

Referring to Figure 5, another embodiment provides a smoking article comprising a tobacco rod and a filter connected to the tobacco rod by means of a tip paper. Preferably a filter 14 comprises a segment 18 of filter beam material in an upstream portion of filter 14 and a flow restriction filter segment comprising a restricting disc 26 having a flow restriction hole 30 situated at downstream of the filter segment 18. Preferably, the cavity 46 extends into the ventilation zone 40 and preferably thereafter to the flow restriction hole 30.

Referring to Figure 6, another embodiment provides a smoking article comprising a tobacco rod and a filter connected to the tobacco rod by means of a tip paper. Preferably the filter comprises a first filter segment 19 constructed of carbon over beam in a portion upstream of the filter, a second filter segment 18 constructed of cellulose acetate beam downstream of the first filter segment 19 and a filter. flow restriction device comprising a restricting disc 26 having a flow restriction hole 30 located downstream of the second filter segment 18. Preferably the cavity 46 extends to the ventilation zone 40 and preferably beyond thence to the flow restriction hole 30.

5 Figure 7 illustrates the process by which the filter rods

currently released are formed for articles for smokers. Figure 7A illustrates a double length paper filter tube 48 'and a double length cellulose acetate segment 18'. The double length cellulose acetate segment 18 'is centrally plugged or otherwise placed 10 into the double length paper filter tube 48' as shown in Figure 7B. Restricting discs 26, 26 are plugged or otherwise placed into position by sliding into opposite ends of tube 48 ', for example using a plunger 27 as shown in figure 7C. Nozzle segments 22, 22 are then plugged or otherwise placed in place by sliding into opposite ends of tube 48 ', for example using plungers 27 as shown in Figure 7D. The resulting double length filter rod is inserted between two separate spaced tobacco rods 12, 12 and secured with the tip paper 16 as shown in Figure 7E. Laser piercing 40 takes place and 20 then the two connected cigarettes are separated. All of these operations can be performed using high speed cigarette manufacturing equipment.

In manufacturing embodiments having filter segment 19 (Figures 3, 4 and 6) a double-ended filter segment 19 'is first placed at the central location of the double-ended tube 48' and insulated plugs 18 are then plugged in. or otherwise placed in place on opposite sides of the double ended cap 19 '. Barring plugs 26 are then plugged or otherwise placed in place on adjacent plugs on opposite sides 18 and nozzle plugs 22 are plugged or otherwise placed on opposite sides adjacent to barring plugs.

Preferred dimensions for an 83 millimeter smoker article include, for example, a 27.1 millimeter filter length, a 7 millimeter end-of-mouth filter segment length, 12 millimeter vent holes from the mouth end of the smoker's article, a restricting disc length of 5 millimeters, a cellulose acetate beam segment length of 2.5 millimeters, 5 and a carbon millimeter filter beam length of 7 millimeters. other

Ventilation zone 40 is established with a first row and optionally second and possibly third rows of vent holes through the tip paper 16 and filter tube 48 '. Accordingly, air is preferably drawn through the ventilation holes of the ventilation zone 40 and into the cavity 46 defined between the flow restriction 30 and the nozzle filter segment 22.

Preferably the ventilation zone 40 is located near or adjacent to the flow restriction 30 so that air is drawn through the ventilation zone 40 and allowed to mix with mainstream smoke before reaching the nozzle filter 22.

Preferably the distance between the ventilation zone 40 and the nozzle filter 22 is at least 5 millimeters or in the range of 5 millimeters to 12 millimeters.

Preferably the ventilation zone 40 achieves a level of

smoking article ventilation of at least 25% and more preferably at least 50% to 90%.

The restrictor disk 26 may comprise an annular partition (transverse wall having one or more holes therein) which establishes the flow restriction 30, with the partition specifically in the form of a reduced diameter orifice. The partition may be frusto-conical and convergent either in or away from the direction of flow of mainstream smoke passing through it. In addition, a pair of partitions may be arranged internally within the restricting disk 26 so as to provide end-to-end symmetry for the restricting disk 26. A filter component having end-to-end symmetry facilitates high fabrication. filter stem speed, where the component works the same whether or not the stem maker directs one end of the component first or reverses it.

A restricting disc 26 having end-to-end symmetry has equal length tubular body portions on opposite sides of a dividing transverse wall. By such arrangement, the fabrication of the filter is facilitated by end-to-end symmetry of the restricting disk 26.

Optionally a second ventilation zone may be located upstream of the flow restriction 30 in addition to or in place of the ventilation zone 40 as provided above.

Manufacturing of smoking articles according to the present disclosure is facilitated by the use of pre-punched tip paper.

In all embodiments, preferably the flow restriction 30 is sized to contribute sufficient pressure loss, 15 such that the smoker's article 10 has a drag resistance of at least 70 millimeters of water or greater, preferably in the range of 90mm to 120mm of water. Preferably the transverse partition wall has a diameter of approximately 7.0 millimeters to 8.0 millimeters, and more preferably approximately 7.4 millimeters to 7.8 millimeters, in which the partition preferably has one or optionally at least one orifice. from a diameter of about 0.5 millimeter to about

0.9 mm and more preferably about 0.5 mm to 0.7 mm.

Since the pressure drop of the restrictor component depends on the open area, several holes can also be used. For example, in one embodiment there are two holes in the partition, 0.5 mm in diameter each.

The restrictor disk 26 may be constructed of paper, a plastic, polymer or metal, and more preferably made of a paper product or a biodegradable plastic / polymer or other suitable material having degradability properties.

Preferably the flow restriction 30 and the nozzle filter 22 are spaced sufficiently apart to reduce the impact of particulate smoke components on the upstream face of the nozzle filter 22. Preferably the flow restriction 30 is approximately 4 spaced up to 15 mm from the nozzle filter 22, more preferably about 6 mm to 10 mm.

It should be appreciated that in all embodiments the filter may be constructed of simple combination techniques typically used in the industry for high speed cigarette manufacturing. Additionally, each embodiment includes tubular support around cavity 60 to provide desired firmness over the entire length of filter 14. In addition, the embodiments provide the necessary amount of drag resistance while maintaining the desired degree. high ventilation through all the smoke. This latter attribute is achieved by relocating the vent zone 40 downstream of the flow restriction 30. In addition, placing the vent in vent zone 40 in separate spaced relationship with the nozzle filter plug 22 ensures a mixture of draft air into the filter 14 through the mainstream smoke zone 40 with smoke drawn from the tobacco rod 12. In one tested embodiment, designs of uniform stains appeared on the mouth end of the nozzle filter 22, which is indicative of good mix.

During smoking a cigarette constructed in accordance with this disclosure, a desired degree of ventilation, for example 50% to 90%, preferably about 70%, is preferably maintained throughout the entire smoking.

In contrast, when ventilation holes are

During the flow restriction 30, ventilation tends to drop as the smoke proceeds through the puff count.

It will be understood that the foregoing description of the preferred embodiments is therefore merely representative of the article and methods of manufacturing it. It may be appreciated that variations and modifications of the different embodiments in light of the above teachings will be readily apparent to those skilled in the art. Accordingly, the exemplary embodiments as well as alternative embodiments may be made without departing from the spirit and scope of the articles and methods as described in the appended claims.

Claims (11)

1. A smoking article comprising two: a tobacco rod adapted to produce mainstream smoke; and a filter having an upstream extreme portion and a downstream extreme portion, said filter arranged to accommodate mainstream smoke in said upstream extreme portion, said filter comprising: a first low to particulate yield filter buffer segment in said upstream end portion: a low to particulate performance nozzle filter buffer segment in said downstream end portion; a flow restriction filter segment at a location adjacent to said first filter segment, said flow restriction filter segment including a restriction establishing a substantial portion of a predetermined drag resistance of said smoking article; tip paper connecting said filter with said tobacco rod and including an air-permissible ventilation zone at a location along said filter between said restriction of said flow restriction filter segment and said nozzle filter; said restriction of said flow restriction filter segment being spaced from said nozzle filter by a distance sufficient to reduce the impact of a mainstream smoke component on an upstream end of said nozzle filter; and a cylindrical segment superimposed by said ventilation zone, said cylindrical segment at least partially defining a portion of a cavity between said nozzle filter and said constraint of said flow restriction filter segment, said cylindrical segment being air transmissible. in said ventilation zone. The smoking article according to claim 1, wherein the cylindrical segment comprises a discrete tubular filter segment and in which a row of perforations extends through said tip paper and tubular filter segment in said zone. ventilation. The smoking article of claim 1, wherein the cylindrical segment comprises first and second integral tubular portions of said flow restriction filter segment, said first and second tubular portions being symmetrical with respect to said constraint. A smoking article according to claim 1, wherein said ventilation zone is spaced from said nozzle filter by a distance sufficient to promote the mixing of draft air through said ventilation zone and mainstream smoke drawn from said nozzle. tobacco rod. The smoker article of claim 1, wherein said flow restriction filter segment includes a trunk-conical cross wall. The smoking article of claim 5, wherein said flow restriction filter segment includes a cross wall that is convergent downstream. A smoking article according to claim 5, wherein said flow restriction filter segment includes a cross wall which is convergent upstream. A smoker's article comprising a tobacco rod and a filter, said filter comprising: a cylindrical tube attached to said tobacco rod with tip paper; a first filter segment at a location along said adjacent cylindrical tube and in a downstream relation to said tobacco rod; a flow restriction filter segment in an adjacent location and in a downstream relation to said first filter segment; said filter further including an adjacent cavity and in a downstream relationship with said flow restriction filter segment; and a venting zone at a location along said cavity comprising perforations through said tip paper and said cylindrical tube, said venting zone in a downstream relationship with said flow restriction filter segment. The smoking article of claim 8, wherein the flow restriction filter comprises a tubular segment having a transverse wall with one or more holes therein. A smoking article according to claim 8, wherein the transverse wall is centrally located between the upstream and downstream ends of the tubular segment. A method of making a filter for a smoker's article comprising: placing a first filter segment in a cylindrical filter tube; placing a flow restriction filter segment in the filter tube adjacent said first filter segment such that said filter further includes a cavity adjacent to said flow restriction filter segment; and establishing a ventilation zone at a location along said cavity, said ventilation zone comprising perforations through said filter tube.