BRPI0707756A2 - smoking filter and smoking article - Google Patents

Abstract

SMOKING ITEM FILTER AND SMOKING ITEM A smoking article filter includes two sections, a first section (2) comprising a longitudinally extending opening (4) surrounded by smoke impervious material (6) and a second section ( 8) comprising a core (10) having a high pressure drop material, a circumscription circular crown (12) having a lower pressure drop filter material than the core. The first section (2) is generally adjacent to the tobacco section (18) of a cigarette (3) at a first end and is spaced from the second section (8). Further, the invention comprises vent holes (20) circumscribing the space or gap (14) between the first and second sections or circumscribing the second section (8).

Description

"SMOKING ITEM FILTER, E5 SMOKING ITEM"

The present invention relates to an improved smoking article filter and to smoking articles incorporating such a filter. More particularly, it refers to a filter for a cigarette.

For many years, cigarette manufacturers have been trying to reduce by filtration the amount of smoke constituents supplied to a smoker. Much effort has been made to provide a smoking article which, when smoked, has a reduced bandwidth and a debuffed profile with reduced puff variance. The bandwidth of a smoking article is a measurement rate between the supply of tar of a smoked cigarette under International StandardsOrganization (ISO) test conditions versus the supply of tar of the same cigarette under other, usually more intense conditions.

Specifically, ISO test conditions involve smoking a cigarette where the puff volume is 35 ml, the puff length is two seconds, and the puff interval is 60 seconds. More intense smoking conditions may include an increase in puff volume, an increase in puff duration, a noticeable decrease in puff, or some combination of these changes. A smaller bandwidth corresponds to a decrease in variance in the amount of smoke constituents provided by a cigarette when smoked under ISO conditions and by the same cigarette smoked under more intense smoking conditions.

The puff profile of a cigarette is the puff smoke supply recorded against puff count. A puff profile having a reduced variance between puffs, that is, a relatively flat puff profile, is one in which the puff smoke supply is more consistent with each puff during the smoking act. Unfortunately, a perfect puff profile does not usually happen when conventional cigarettes are smoked. It has been known for some time in the tobacco industry that the supply of smoke particulate phase constituents, or "Total Particulate Matter" (PMS), is not uniform during smoking. Under ISO machine smoking conditions, "puff strength" - measured by the amount of smoke particulate phase constituents in each puff - increases significantly from the first puff to the last puff. This increase in particulate matter in the posterior puffs is caused by a number of defactors, including a decrease in filtering effectiveness of the tobacco rod, a decrease in the level of ventilation of the tobacco rod through the decigar paper - both of which result from the length of the tobacco rod. tobacco is reduced during smoking - and an increase in the potential for smoke particle phase constitution of the tobacco rod due to the deposition of the smoke particulate phase constituents from the previous puffs over the rod.

The proportion of smoke constituents between the first and last puff in a cigarette varies based on a number of product design characteristics, including total smoke constituent production for that product. Typically, ratios between 2 and 4 for "full flavor" products (having more than 10 mg TPM), between 3 and 5 for lights (5-10 mg TPM), and between 4 and ultra-lights (less than 5 mg of PTM) are achieved under ISO machine smoking conditions. Higher levels of ventilation used in "light" and "ultra-light" products increase the proportion even as the smoke production of the products decreases. This imbalance in the production of smoke constituents between the first and last puffs in a cigarette may lead to consumer rejection of the product due to a perception that the cigarette is too "weak" in the first puffs or too "strong" in the final puffs. This problem is exacerbated for products that produce a lower level of smoke constituents due to the much larger differences between the amount of smoke constituents in the first and last puffs. Consequently, there is a desire to provide a cigarette with a flatter, trimmed profile. able to provide a similar level of smoke constituents in both the first and last puffs.

In addition, it is known that increasing the level of smoke constituents supplied in the final puffs represents a significant proportion of the total amount of smoke constituents generated in all cigarette products. Consequently, by reducing the supply of smoke constituents in the final puffs, the amount of smoke constituents supplied in total will also be reduced.

Accordingly, it is an object of the present invention to provide a smoking article filter that efficiently and effectively reduces the supply of smoke constituents supplied to a consumer elsewhere.

It is a further object of the present invention to provide a smoking article filter which is capable of decreasing the bandwidth of a smoking article and / or capable of decreasing the variance of the smoke constituent supply between puffs.

The invention comprises a filter for articles for combining at least two different sections. A first section comprises an inner area and a surrounding area, the inner area and the surrounding area comprising a smoke flow path and a relatively smoke impermeable material area. The relatively smoke-impermeable material increased flow resistance when compared to the smoke flow resistance of the smoke flow path. In one embodiment, the smoke flow path and the relatively smoke-impermeable material are arranged in a circular core and crown configuration, with the smoke flow path forming the core. In an alternate embodiment the smoke flow path forms the circular crown and the relatively smoke impermeable material forms the core of the first section.

The second section comprises a smoke impact zone in axial alignment with the smoke flow path of the first section. The second section of the filter may comprise a core comprising high pressure drop filter material and a circular crown comprising a pressure drop material smaller than the core and vice versa.

In one embodiment of the filter of the present invention, the first and second sections are separately spaced from one another by an intermediate gap.

In one embodiment of the invention, the filter is designed so that the smoke flow path of the first section is axially aligned with the core of the second section. In this embodiment, the second section core is made of high pressure drop filter material when compared to the second section circular crown filter material. In use, smoke exits the smoke flow path of the first section so that a Much of the smoke - especially the heavier smoke constituents - impact the second high pressure drop core. Alternatively, in this embodiment, a relatively smoke-impermeable material plug may be located in the second section in axial alignment with the outlet of the first-stage smoke flow path, so that a large portion of the smoke - especially the heavier smoke constituents - impact on the relatively smoke-impermeable material plug on the second section. Impact filtering occurs when smoke particles strike a material and are trapped by it, so in the embodiments described above, smoke components impacting the second section's smoke impact zone will be retained by it.

In another embodiment, the invention additionally comprises ventilation holes circumscribing the second section or circumscribing the space or gap between the first and second sections. When the cigarette is smoked, the smoke flow path of the first section begins to fill with condensed particulate smoke constituents and are deposited in the smoke flow path, and the smoke flow through it begins to be restricted. This restriction leads to an increase in fall depression in the first section. As the pressure drop increases, more is brought into the filter through vent holes thereby, as smoking proceeds on subsequent puffs, causing a decrease in the variance in the supply of subsequent puffed smoke constituents that would occur. otherwise as smoking proceeded due to the known phenomenon of increased supply of smoke constituents in the later puffs of a smoking article.

Ventilation may be provided by means known to one skilled in the art, such as laser or mechanical drilling.

The filter may further comprise additional sections. Additional filter sections may comprise conventional filter material such as cellulose acetate, polypropylene or paper. Additional filter sections may alternatively or additionally comprise carbonated material, eg carbon. activated, deresin material, for example amberlite, duolite or equivalent, and / or catalytic material.

The present invention further provides a smoking article comprising a smokable material rod, a wrapper surrounding the smokable material rod, and a filter according to the present invention attached to the smokable material rod. The first section of the filter according to the invention is, preferably adjacent the smoking article rod of the smoking article at one first end and is spaced from the second section of the filter at an opposite end.

The filter of the present invention and the smokable material rod may be interconnected by any means known in the art, such as a nose wrap. As is commonly known, the tip wrap can circumscribe the filter along its length and overlap with the smokable material rod. The nose wrap may be attached to the rod wrap of smokable material by conventional means, for example by adhesive.

In the smoking article of the invention, the filter and the smokable rod are preferably in coaxial alignment with one another.

In one embodiment of the smoking article according to the invention, the filter may comprise one or more additional filter segments. The additional filter segment (s) may be located between the smokable material stem and the first filter section, and / or may be located at the mouth end of the second filter section. .

Aspects and advantages of the present invention will be further appreciated when the detailed description of the preferred embodiment is taken in conjunction with the accompanying drawings, in which:

Figure 1 is a perspective view of a cigarette selected compositions shown in section; and

Figure 2 is a cross section of an embodiment of the cigarette shown in Figure 1;

Figure 3 is a cross-section of another embodiment of the cigarette shown in Figure 1;

Figure 4 is a perspective view of another embodiment of the cigarette shown in Figure 1;

Figure 5 is a perspective view of yet another embodiment of the cigarette shown in Figure 1;

Figure 6 is a graphical representation of the effectiveness of the various embodiments of the invention in reducing total particulate matter; and

Figure 7 is a graphical representation of the effectiveness of an embodiment of the invention in reducing bandwidth.

Although this invention is capable of embodiments in many different forms, multiple embodiments are shown in the figures and will be described in detail herein. The present disclosure should be considered an example of the principles of the invention and is not intended to limit the broad aspects of the invention to the illustrated embodiments.

Referring to Figure 1, the invention comprises a cigarette filter 1 and a cigarette 3 designed to reduce the supply bandwidth of a cigarette in use. The cigarette 3 comprises a cigarette section 18 and a filter 1. The filter 1 comprises a first section 2 comprising an inner area 4 and a first surrounding area 6. In one embodiment, the first section 2 is at the end of the cigarette 3 closest to the section The diameter of the inner area 4 is preferably between 0.5 and 3.0 mm and between 5 and 10 mm in length. It will be understood that the length of the smoke flow path will be determined by the length of the filter; The length of the smoke flow path of the first section, however, will be equal to the length of the first section.

For the filter to function properly, the inner area 4 and the surrounding area 6 must comprise a smoke flow path and an area that is relatively impervious to smoke. In the preferred embodiment, the inner area 4 is the smoke flow path and the surrounding area 6 is impervious to smoke. In this embodiment, the smoke travels through the smoke flow path 4 and exits the cigarette at a high speed. In another embodiment, however, the smoke flow path may be formed by the surrounding area 6 with the inner area 4 being formed of smoke impervious material.

Smoke flow path 4 may employ a number of different embodiments. For example, the smoke flow path 4 may comprise a tube 30, as shown in Figure 2, or a smaller pressure drop material 40 - such as cellulose acetate - than that of the surrounding area 6, as shown in Figure 3.

Referring again to Figure 1, filter 1 additionally comprises a second axially aligned section 8 comprising a core 10 circumscribed by a circular crown 12. The inner core 10 of the second section 8 is axially aligned with the inner area 4 of first section 2. As can be seen more clearly in Figure 2, filter 1 further comprises a gap or gap 14 located between first section 2 and the second section 8. The gap 14 may be in the range of 0.0001 mm to 4 mm in length, but in various embodiments of the invention may be in the range 0.1 - 3.8 mm, or in the range 0.5 - 3.5 mm, or in the range 1-3 - mm, or in the range 1.5 - 2.5 mm and, In one particular embodiment, it is about 2 mm. If the gap is too wide, heavier smoke constituents will diffuse into the gap 14 between the first and second filter sections before impacting the second section 8, which would negatively impact filter performance 1. Along with the rest of filter 1 Oval 14 is wrapped in plug wrap and attached to the rest of the cigarette sharpener with conventional tipped paper.

Both the core 10 and the circular crown 12 of the second section 8 should form a relatively smoke impervious impact zone. If the smoke flow path in the first section is the inner area4, then the impact zone of the second section 8 will be in the core region 10. The smoke impact section may extend over the entire length of the second section 8 as shown in Figures 1-3, or, as shown in Figure 4, it may be a small disk 32 of smoke-impermeable material attached to the end of a regular filter section34. In the embodiment shown in Figure 4, smoke would diffuse behind smoke-impermeable material, but the heavier smoke constituents would be removed first through their impact on the smallest 32.

If the smoke flow path in the first section 2 is the surrounding area 6, then the impact zone of the second section 8 will be in the region of the circular crown 12. As shown in Figures 1-3, this may be a relatively circular material 12. impermeable along the total length of the second section 8, or it could be a circular crown disc 36 with the same material affixed to the end of the regular filter section 34 as shown in Figure 5.

When core 10 acts as the impact zone, the diameter of the outer circular crown 12 is preferably 40% of the diameter of filter 1, but the filter will function properly, however, while core 10 is larger than the diameter of Likewise, when the circular crown 12 acts as an impact zone, its width should be greater than that of the smoke flow path formed by the surrounding area 6.

The length of the second section 8 can be any length to create the desired total length of filter 1, and is usually about 5 to 50 mm. The second section 8 is generally the mouth end of the cigarette filter.

In one embodiment, the filter 1 additionally comprises vent holes 20, which may be positioned in either the second section 8 or the gap 14.

Filter 1 reduces the delivery bandwidth in two different ways. First, when the cigarette is being smoked, smoke passes through the smoke flow path of the first section 2 and enters the high-speed chamber 14. Due to the short distance between filter sections 2, 8 and the high speed at which smoke travels, most smoke particles do not disperse before impacting and clinging to the high pressure drop material of the second section 8 opposite the path. smoke flow from the first section 2. Heavier smoke particles sedisper less than lighter particles, leading to less total particulate matter leaving the cigarette. The stronger the puffs on the cigarette, the less smoke dispersion occurs, and the more filtration takes place.

The second mode in which bandwidth is reduced involves the use of ventilation holes. As the cigarette is smoked, tube 4 in the first section 2 progressively fills with particulate smoke constituents, which increases resistance to smoke flowing through dot 4. This increases the pressure drop through the first section 2, which makes more air. diluted be pulled through the vent holes 20 when the fuming inhale. Diluted air enters the vault 14 or the second section 8 through the vent holes 20 circumscribing the second section 8 or the vault 14. This further concentrates the smoke in the middle of the vault 14, thereby causing most of the smoke to impact the core 10, which in the preferred embodiment comprises the impact area of the second section 8.

While what is believed to be preferred embodiments of the present invention has been described herein, those skilled in the art will recognize that further changes and changes and additional modifications may be made to them without departing from the spirit of the invention, and it is intended to claim all such changes and modifications that fall within the scope of the invention. within the true scope of the invention.

Four different embodiments of the invention were tested to determine the amount of nicotinatotal free particulate matter in each puff and to determine if the supply changed as the number of puffs increased. In Examples A and B, the first and second sections were 11 and 14. mm in length respectively, there was a gap of 2 mm between sections. In examples C and D, the first section was 11 mm long and the second section was 16 mm long, and the gap between the two sections was 0.001 mm. All examples A, B, C and D had a tube in the first section with an internal diameter of 2 mm. In Examples A and C, the circular crown of the second section was made of high pressure drop material while in Examples B and D the circular crown of the second section was made of smaller pressure drop material.

Table 1 below and Figure 6 demonstrate the beneficial effect the invention has on smoothing the puff profile when compared to a "control" cigarette:

Table I - Pour to puff supply of nicotine-free wet particulate matter (in mg)

<table> table see original document page 12 </column> </row> <table> In addition, Table 2 and Figure 7 show the reduction in bandwidth that occurs when an embodiment of the invention - Example D - is smoked under various conditions. The more extreme the conditions, the better the performance of Example D compared to the control cigarette. Under ISO conditions (35 ml puff volume, 2 second puff length, 60 second puff interval), the difference between the amounts of particulate matter is relatively small. But as the total puff intensity increases, the filter efficiency of the invention improves, as demonstrated by the large difference in PMS between the control and Example D.

Table 2 - Provision of TPM at ISO and other conditions

<table> table see original document page 13 </column> </row> <table>

The various embodiments of the invention have a measurable beneficial effect on decreasing bandwidth, decreasing MPTP, and smoothing the puff profile of a cigarette as it is smoked. It is apparent that the location of the high pressure drop material and gap width will modify the performance of the invention while still using the concepts of the present invention. These variations are supposed to fall within the limits of this application.

Claims (42)

A filter for smoking articles, characterized in that it comprises: a first section comprising smoke-impermeable material having a longitudinally extending smoke flow path therethrough, a second section spaced from and aligned axially with said first section said second section comprising a core portion circumscribed by a coroacircular portion, wherein one of said core portion and circular crown portion comprises minor pressure drop material, wherein said smoke flow path is longitudinally aligned with said portion. Core or ring crown which comprises high pressure drop material. Smoking article filter according to claim 1, characterized in that said smoke flow path is an opening arranged centrally in said first section. Smoking article filter according to claim 2, characterized in that said smoke flow path includes a pipe therein. Smoking article filter according to claim 1, characterized in that said smoke flow path comprises pressure drop material smaller than said smoke impermeable material. Smoking article filter according to claim 4, characterized in that said lower pressure drop material is centrally disposed in said first section. Smoking article filter according to claim 4, characterized in that said lower pressure drop material circumscribes said smoke impervious material to a circular crown / core ratio. Smoking article filter according to Claim 2, characterized in that it further comprises ventilation holes. Smoking article filter according to claim 7, characterized in that said ventilation holes circumscribe said second section. Smoking article filter according to claim 7, characterized in that said ventilation holes are located between said first section and said second section. A filter for smoking articles according to claim 7, characterized in that said venting holes allow air from outside to enter said filter. Smoking article filter according to claim 10, characterized in that the amount of air drawn through said ventilation holes increases as the said pipe fills with air. Smoking article filter according to claim 1, characterized in that said smoke flow path is between 5 and 10 mm in length. Smoking article filter according to claim 1, characterized in that said smoke flow path is between 0.5 and 3 mm in diameter. Filter for smoking articles according to claim 1, characterized in that the diameter of said core of said second section is approximately 60% of the diameter of said filter. Filming filter according to claim 1, characterized in that there is less than 4 mm between said first section and said second section. 16. Smoking article, characterized in that it comprises a rod of smokable material; a wrapper circumscribing said smokable rod; a filter comprising a first section and a second section, said first section having a first end and an opposite end, said first end being attached to said smokable material rod, said first section comprising smoke impervious material having an opening extending longitudinally therethrough. centrally arranged; and said second section spaced from and, axially aligned with said end of said first section, said second section comprising a core portion comprising high pressure drop filter material circumscribed by a circular crown portion comprising a fall filter material pressure lower than said core portion. Smoking article according to claim 16, characterized in that said opening includes a namesma tube. Smoking article according to claim 17, characterized in that it further comprises ventilation holes. Smoking article according to claim 18, characterized in that said ventilation holes circumscribe said second section. Smoking article according to claim 18, characterized in that said ventilation holes are located between said first section and said second section. Smoking article according to claim 18, characterized in that said ventilation holes allow air from outside to enter said filter. Smoking article according to claim 21, characterized in that the amount of air drawn through said ventilation holes increases as said pipe dries with air. Smoking article according to claim 16, characterized in that said smoke flow path is between 5 and 10 mm in length. A smoking article according to claim 16, characterized in that said smoke flow path is between 0.5 and 3 mm. Smoking article according to claim 16, characterized in that the diameter of said core in said second section is approximately 60% of the diameter mentioned in the filter. Smoking article according to claim 16, characterized in that there is less than 4 mm between said first section and said second section. A filter for smoking articles, characterized in that it comprises: a first section comprising smoke-impermeable material having a longitudinally extending smoke flow path therethrough, a second section spaced from and aligned axially with said first section wherein said second branch comprises a mouth end and a span end, a smoke impervious blocking patch attached to the gap end of said second section, wherein said smoke flow path is longitudinally aligned with said locking seam. A filter for smoking articles according to claim 27, characterized in that said smoke flow path is an opening centrally disposed in said first section. A filter for smoking articles according to claim 28, characterized in that said smoke flow path includes a tube therein. A filter for smoking articles according to claim 27, characterized in that said smoke flow path comprises lower pressure drop material than said smoke impermeable material. A filter for smoking articles according to claim 30, characterized in that said lower pressure drop material is centrally disposed in said first section. A filter for smoking articles according to claim 30, characterized in that said lower pressure drop material circumscribes said impermeable material to a circular crown / core ratio. 33. Filter for smoking articles according to claim 28, characterized in that it further comprises ventilation holes. 34. Filter for smoking articles according to claim 33, characterized in that said venting holes circumscribe said second section. 35. Filter for smoking articles according to claim 33, characterized in that said ventilation holes are located between said first section and said second section. A filter for smoking articles according to claim 33, characterized in that said ventilation holes allow air from the outside to enter said filter. 37. Smoking article filter according to claim 36, characterized in that the amount of air drawn through said ventilation holes increases as said pipe fills with air. 38. Filter for fasteners according to claim 27, characterized in that said smoke flow path is between 5 and 10 mm in length. A filter for smoking articles according to claim 27, characterized in that said smoke flow path is between 0.5 and 3 mm. 40. Filter for smoking articles according to claim 27, characterized in that there is less than 4 mm between said first section and said second section. 41. Filter for smoking articles, characterized in that it comes down substantially as described herein with reference to the accompanying drawings. 42. Smoking article, characterized in that it is substantially as described herein with reference to the accompanying drawings.