JPH04503753A - Filter with uniform tar flow profile - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Filter 1 Goto 1 with uniform tar outflow profile The present invention provides a more accurate profile of tar efflux to the smoker than previously possible. A novel cigarette smoke filter element that allows uniform cigarettes incorporating such filter elements.

ltt confused Once when a smoker or smoking device smokes a conventional filter cigarette It is well known that the amount of tar in the suction increases with each suction. It is being The tar flow during the last few puffs is the same as the tar flow during the first few puffs. It is normal for it to be several times larger than the output. Therefore, the target during the last several sucks may be perceived as overly strong by some smokers.

Therefore, if the tar efflux profile could be made slightly more uniform, smokers You will find that the cigarettes are smoother.

In the past, by changing the shape of the filter, cigarettes with a "uniform puff" were created. There were many attempts to accomplish this. Mullor U.S. Patent No. 2,763, No. 287 and U.S. Pat. No. 3,809,097 to Clayton et al. Place the disc inside the cigarette filter rod in a direction transverse to the smoke stream. We proposed that it be used by positioning it. However, these designs improve filtration efficiency It has no ability to even out the tar profile of cigarettes. .

Pattagon, U.S. Pat. No. 3,648,712, discloses that ordinary cellulose A low gas permeability device placed transversely inside the acetate filter rod. He proposed using a disc. The diameter of that disc is the diameter of the filter rod This filter has improved filtration efficiency as it is 5-25% smaller than There is no ability to uniformize the tar flow profile.

British Patent No. 1,339,238 to B.A.T. Between the Lurose acetate filter rods, the blocking plug I suggested placing a card (1 card). This disc is one for the smoke to pass through. It has an orifice of. The disadvantage of this design is that during the final suck, the Unacceptable pressure drop for a cigarette as the orifice of the plug becomes obstructed No. 3,882 to Brackmann et al. No. 877 uses a fine fiber disk between two filter rod sections. I suggest placing it. This filter is designed to increase filtration efficiency ing. However, this does not lead to more uniform tar flow. It was. Furthermore, during the final draw the pressure drop increases to an unacceptable level. You may end up doing it.

U.S. Patent Nos. 4,460,000 and 4,469,212 to Browns et al. No., the entire amount of smoke going to the cellulose acetate filter rod section passes through. Compound filters containing perforated barrier discs such as We are proposing that. As the smoking process progresses, tar becomes pores one after another. It builds up on the cellulose acetate fibers around the exit point. This design A disadvantage in this case is that tar buildup near the perforations may interfere with the flow of the cigarette filter. This would greatly increase the dynamic resistance to unacceptable levels.

British Patent No. 2,102,271A, No. 2,10 of Filtrona (UK) No. 3,065A and No. 2,105.566, the smoke passes through the filter rod. There are two flow paths for flow, one with low filtration efficiency and low pressure drop. A single roll cigarette that proposes the use of a route with high filtration efficiency and a large pressure drop. During the first few puffs of smoke, the smoke flows through a path with a low pressure drop. is intended to be used. After that, blocking is required for paths with small pressure drop. This mechanism prevents the footwear from switching to flow through the path with the highest pressure drop. It will be done. The disadvantage of these filters is that they are extremely complex and difficult to manufacture. Is Rukoto.

U.S. Pat. No. 4,747,418 describes an attempt to achieve a more uniform tar flow. As a reference, a filter element in the form of a membrane with a large number of fine pores is Multiple holes or conventional flaps downstream of the membrane through which the suctioned air can pass. For use with filter materials. This also requires a complex and expensive structure. required.

ILL standing 1j According to the invention, two different filters are used to achieve a more uniform tar flow. An improved filter structure is provided in which a combination of filter materials is provided.

Accordingly, one aspect of the present invention is to provide a long outer cylinder of tobacco smoke filter material and an inner long cylinder of tobacco smoke filter material. A long fine fiber cylinder on the side and an axial side on the radially inner side of the fine fiber cylinder. Provided is a cigarette smoke filter element characterized in that the cigarette smoke path has a directional cigarette smoke path. be done. Flow of cigarette smoke through an outer cylinder of smoke filter material The resistance is much higher than in the axial passage.

To remove cigarette smoke from the cigarette to which the filter element is attached, One end of the filter element to point only into the cylinder of smoke filter material. A tobacco smoke flow path directing means is disposed at the tobacco smoke flow path directing means.

By doing so, the cigarette is directed from the cigarette into the outer cylinder. The smoke first passes through the outer cylinder, then through the inner cylinder, where there is a small flow resistance. It passes into the axial flow path.

As the smoking of the cigarette progresses, the length of the inner cylinder is filled with tobacco smoke. As the area blocked by filtered tar gradually increases, tobacco smoke The length of the flow path forced through the cylinder increases sequentially. More details below This effect is explained by the fact that the tar in the cigarette smoke that goes to the smoker's mouth is This leads to a more uniform outflow.

- the cylinder of fine fibers is placed between two outer porous support layers; Good, fine fibers are described in the aforementioned U.S. Pat. No. 3,882,877. It is formed in such a way that it is The disclosure in that patent is hereby incorporated by reference. Built-in. Within its cylindrical layer, the fine fiber is diameter, generally from about 0.5 to about 10 microns, to achieve the desired filtration. The cylindrical layer, which may have a diameter of having a thickness convenient to achieve throughput, generally from about 0.05 to about 4 mm. fine fibers to the desired extent to achieve the desired filtration. In general, packs are compressed to about 0.05 to about 0-3 g/ac. It's good to have one.

The outer ring of filter material is of the type commonly used in cigarette filters. Known filter media, generally a cell whose fibers extend primarily axially along their length. Lurose acetate fiber bundle or DANAKLO NES) (Polypropylene manufactured by Danaklon in Denmark/ If it is made of a non-woven fibrous material such as polyethylene bicomponent fiber) good.

Fine fibers are highly effective filtration media for cigarette smoke and are Removal of liquid components from smoke as described in National Patent No. 3,882,877 It functions as follows. Its filtration is so effective that the filter closes quickly. This may result in blocking and not allowing further smoke filtration to take place.

The smoke from the cigarette is in the same direction as the cigarette filter components extend. In the novel cigarette smoke filter according to the present invention, which is axially pulled, , the uplifting effect is used to advantage. When I had my first few puffs, Smoke enters the annular material and then travels through fine fibers to the smoker's mouth. It passes into a laminar flow passageway with low drag. The fine fumes where the smoke is pulled through The fibers quickly become occluded and as a result, the smoke passes through the fine fibers with little resistance. Longer travel through the annular material before being able to pass into the smoke path You will be forced to go through the route.

As the cigarette smoke progresses, before the cigarette smoke passes through the fine fiber. The distance that must be traveled through the annular material increases progressively. filter length Along its entire length, fine fibers remove a uniform amount of droplet material from the smoke. Ru. This is because each successive section of the fiber carries only up to the same maximum amount of droplets. This is because it cannot be captured by filtration. However, smoke passes through the annular filter material. , by forcing smoke aerosols to take sequentially longer travel paths. The amount of droplets removed from each step becomes larger sequentially. The result of this filtration action is that the smoker's mouth This means that the smoke entering the cigarette has a substantially uniform tar content; The problem of increasing tar leakage from compensated by progressively increasing the filtration of tobacco smoke in the This is done without any significant pressure drop occurring.

Accordingly, another aspect of the present invention is to provide a filter for introducing tobacco smoke from a cigarette into a smoker's body. A method is provided for achieving a more uniform flow of tobacco smoke, the method comprising: However, from the burning cigarette, first the outer cigarettes, which have a relatively greater resistance to smoke flow. into the cylinder of smoke filter material and from there through the inner fine fiber cylinder. and pass into the axial flow path of low resistance for the smoke to the smoker's mouth. Filter out tar and other substances from smoke in both the outer and inner cylinders. The percentage of the inner cylinder that no longer functions as a filter increases gradually As the flow path through the outer cylinder through which the smoke passes increases, As the length increases sequentially, tar etc. are thereby removed from tobacco smoke. The filtering method is characterized in that the proportion of filterable substances in the filtering method is made larger than in the sequential filtering method.

Na FIG. 1 shows a novel cigarette filter constructed as one embodiment of the present invention. FIG. 2 is a schematic cross-sectional view.

ruta's Looking at the drawings, a cylindrical cigarette 10 is shown with a cigarette rod 12 and a cigarette rod 12 in the present application. A novel filter of construction that is currently considered by those skilled in the art to be the best mode of carrying out the invention. The eight-roll tobacco rod 12 containing the tar 4 has a conventional wrapper 16. and is coupled to filter 14 by a conventional cork wrap 18.

Filter 14 has an outer, conventional cellulose acetate shell having an outer wrapper 22. It includes an annular body 20 of fiber bundle material. The fine fiber cylinder 24 is an annular body. 20, which is typically the most radially innermost part of the flow resistance. Small tissues are supported between the outer layers.

The cylinder 24 includes the annular body 20 and a material having low flow resistance such as acetate having low flow resistance. It is sandwiched between an inner plug 26 made of thin material. The inner plug 26 is It may be omitted altogether if desired, but it is necessary to provide mechanical strength and stability to the structure. Alternatively, a star-shaped cross-section or a cylindrical shape may be used. Extrusions with other convenient shapes, such as creating smoke channels on the inside radially. A support structure such as a molded plastic core may be used.

At the end of the filter 14 opposite the smoking end of the cigarette 10, the filter , a stream of cigarette smoke flows directly from the cigarette rod 12 to the acetate plug 2. 6, and the seal is, for example, acetate plastic. overlapping the crushed portion 32 and/or the end of the acetate plug 26. This is done by providing a circular partition wall 34 as shown in FIG.

By providing such flow directing means, it is possible for the smoker to Any smoke drawn from the fiber bundle 12 will not enter the outer acetate fiber bundle annulus 20. becomes certain. The inner plug 26 has a relatively high flow resistance than the annular body. Cigarette smoke because it provides a flow path with low flow resistance for cigarette smoke. is the acetate plug 26 radially inward from the annular body 20 where the resistance is large. Let it flow into the. As a result, a cylinder 24 of fibrous filter material is formed. You will pass through it.

Smoke follows the path of least resistance, so smoke initially travels through fine fibers. A short section is passed through the toroid material 20 before flowing into the acetate plug 26. Flows only over long distances. However, fine fibers do not provide effective filtration of tobacco smoke. It removes particulate matter such as droplets containing tar accompanying the smoke, so the final Ultimately, the fibers will not be able to perform any further filtration work. therefore , the fine fibers in the cylinder 24 are successively filtered in a direction towards the smoking end of the cigarette 10. Stop overworking yourself.

Therefore, cigarette smoke is directed radially inwardly toward the acetate plug 26. The filtration material must move through the annular filter material 20 before being able to migrate into the filter material 20. The path length becomes progressively longer. In this way, the annular material 20 The degree of filtration applied becomes progressively greater, so that the cigarette 10 is smoked. The overall degree of filtration during It is compensated that the tar produced by the co-rod 12 will be more sequentially .

In the illustrated embodiment, smoke may pass directly from the annular material 20 to the smoker's mouth. deer However, the dominant smoke flow path is through the acetate plug 26, which is This is because the flow resistance of smoke there is small. If desired, remove all smoke. An annular barrier is provided to allow flow through the Tate plug 26 and into the smoker's mouth. It may be provided so as to overlap the smoking end of the five-ring material 20.

Filter element 14 may be formed by any convenient method. One example In this case, instead of the acetate plug 26, the filtered smoke going to the smoker is passed through. extruded plastic with a star-shaped cross-section that allows for multiple flow channels. There is Ku Core. In this case, the plastic core is placed in a fine fiber extruder. Continuously reciprocate in front. Rotating the plastic core around its axis , the fiber is placed on the outer circumference of the core, i.e. the radially outermost point of each point of the star. At , it is collected into a uniform layer 24 . A relatively small amount of fine fibers The cross section of the shape may overhang irregularly into the air passage between each point of the shape, It seems that the pressure drop between each leg of the star has a noticeable effect on small ducts. Not to a certain degree.

The continuous rod is then passed through a filter making machine where the cores are spaced at regular intervals. Crimped, the ordinary high efficiency filter material 20 is The primary filter applied to the outside of the fiber layer 24 is a conventional filter. Wrapped in the rag wrap 22 and cut at the crushed point, a plurality of films are formed. A data element 14 is created.

The present invention produces an unacceptable level of pressure drop when a cigarette is smoked. By successively increasing the degree of filtration without delay, the burden on smokers is increased. Provides a novel cigarette filter structure to even out the flow of smoke. Cigarettes are one of the major products in commerce and are within the scope of the present invention. Various modifications are possible.

1@um+-Apphem+, *No PCT/CA 90100070 country international investigation report CA 9000070

Claims (10)

[Claims] 1. In a cigarette smoke filter element, the outer long cigarette smoke filter material A cylinder, an inner long fine fiber cylinder, and a radially inner side of the fine fiber cylinder. There is an axial cigarette smoke path in the outer cylinder of smoke filter material. The resistance to the flow of cigarette smoke through the axial flow path at The filter element is also large, and at one end of the filter element, the filter element is attached. The outer circle of tobacco smoke filter material removes cigarette smoke from a cigarette being smoked. Particularly, tobacco smoke flow path directing means are placed to direct the tobacco smoke only into the cylinder. Filter element to be used as a signature. 2. The fine fibers are about 0.5 to about 10 microns within said long cylinder. 2. The filter element of claim 1, having a diameter of . 3. The fine fiber cylinder has a thickness of about 0.05 to about 4 mm and a thickness of about 0.05 to about 4 mm. 3. The filter element of claim 2, having a density of about 0.3 g/cc. 4. The outer cylinder of tobacco smoke filter material is made of conventional cellulose acetate fibers. 4. The filter element of claim 3 which is a bundle of filter material. 5. said deflection means being by means of a septum means at said one end of said filter element. 5. A filter element according to claim 4, wherein the filter element is made of 6. The axial cigarette smoke path is made of acetate material with low flow resistance. 5. A filter element according to claim 4, wherein the filter element is made of 7. Said low flow resistance acetate material is placed at said one end of the filter element. 7. The filter element of claim 6, wherein the filter element is collapsed to stop the flow of tobacco smoke. Basic. 8. The axial cigarette smoke path is a long plastic tube with a star-shaped cross-section. radially inside the cylinder of fine fibers. 5. The filter element of claim 4, wherein the filter element is provided with a plurality of flow paths on the sides. 9. Claims 1 to 8 in combination with a cigarette rod in a cigarette. The filter element according to any one of the preceding claims, wherein said tobacco smoke flow path directing means a stage of the cigarette of the filter element; Located near the connection to the rod A filter element. 10. More uniform flow of tar from the cigarette into the tobacco smoke that enters the smoker's mouth In the method for achieving smoke release, tobacco smoke is removed from the burning cigarette. First, inside the outer cylinder of tobacco smoke filter material, which has a relatively large smoke flow resistance, From there, the smoke passes through an inner fine fiber cylinder to the smoker's mouth. Pass into the axial flow path with low flow resistance, connecting the outer cylinder and the inner Both side cylinders filter filterable substances such as tar from the smoke, and the inner cylinder As the proportion of the part of the cylinder that ceases to function as a filter gradually increases, the smoke will pass through. The length of the flow path through the outer cylinder increases sequentially, and This will progressively increase the proportion of filterable substances such as tar that are removed from tobacco smoke. A method characterized by increasing the size.