JPH0453507B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel cigarette filter, and more particularly to a cigarette filter that reduces the outflow of tar and nicotine components while providing a smoker with a rich flavor. The harmful effects of smoking on health have long been debated, and for this reason it is common practice to attach filters to cigarettes to reduce the outflow (referred to as delivery) of smoke components into the oral cavity when smoking. However, in recent years there has been an increasing demand for cigarettes with reduced delivery of tar and nicotine. The easiest way to reduce the delivery of tar and nicotine is to increase the packing density of the tow and install a high ventilation resistance filter, or to reduce the cross-sectional area of the fibers (hereinafter referred to as filaments).
This can be achieved by increasing the surface area per unit weight by changing the cross-sectional shape and installing a filter with high filtration efficiency, but even if this method can physically remove tar and nicotine, it is extremely difficult and You end up with a filter with a different taste. Another method is to provide small ventilation holes (called vent holes) around the outer periphery of the filter to dilute the smoke from the vent holes and reduce the delivery of tar and nicotine. However, simply diluting tobacco smoke dilutes the original taste of tobacco and impairs its aromatic taste. In particular, in the case of air dilution, the reduction of nicotine components is selectively large, which tends to disrupt the balance of flavor and aroma. On the other hand, a hollow tube is placed in the center of the filter,
By reducing the ventilation resistance in the center of the filter, thinner smoke flows out from the periphery and thicker smoke flows out from the center, reducing overall delivery while satisfying the smoker's taste. Several filters with different structures have been proposed. For example, in the device disclosed in Japanese Patent Application Laid-open No. 57-132872, a groove extending in the length direction of the filter plug is provided at the peripheral edge of the filter plug and communicates with the outside via a vent hole, and a groove is provided at the center of the filter plug. A hollow tube is placed, in this case air enters the smoker's mouth through a groove, cigarette smoke collects in the hollow tube, and the concentrated smoke enters the smoker's mouth. It's summery. The air flowing in through the vent hole reaches the oral cavity directly without being mixed with smoke in the filter, and in this case, the smoke is simply diluted with air, which also tends to impair the balance of aroma and taste. As a result of intensive research on the above-mentioned problems, the inventor has developed a dual-structure filter, which has a hollow tube arrangement and vent holes, and has reduced the total amount of tar and nicotine that flows out. We succeeded in developing a filter with a better taste by increasing the rate of reduction in tar delivery to a greater extent than that of nicotine, which is a flavor component. That is, the present invention provides a tobacco part side fiber bundle, a mouthpiece side fiber bundle which is provided on the mouthpiece side of the tobacco part side fiber bundle and is made of fibers thicker than the fibers of the tobacco part side fiber bundle, and a central part of the mouthpiece side fiber bundle. a hollow tube made of an air-impermeable material disposed in the air-impermeable material, and a vent hole provided in the tobacco-side fiber bundle portion of the air-impermeable exterior member that encloses the tobacco-side fiber bundle and the mouthpiece-side fiber bundle; This invention relates to a cigarette filter characterized by comprising: Cellulose acetate fibers, which are currently used in the filters of filtered cigarettes on the market, are particularly suitable for the fiber bundles used in the practice of the present invention. Thermoplastic plastics such as vinyl chloride resin, polyethylene resin, and polypropylene resin can be advantageously used as the hollow tube. In order to arrange the hollow tube at the center of the fiber bundle on the suction side, for example, a plasticizer is applied to a crimped continuous tow that has been opened as described in Japanese Patent Application Laid-Open No. 54-37900. When feeding the tow to a shaped guide and converging it, a hollow tube is inserted into the center of the flow of the tow from a hollow tube insertion guide provided between the guide section and the holding lid that receives the tow in the wrapping and forming section. There is a way to wrap it up with wrapping paper. A primary wrapper during manufacturing of a filter section consisting only of fiber bundles, and a second wrapper that connects and wraps a filter section in which a hollow tube is placed in the center of the fiber bundle on the suction side cut to a predetermined size and a filter section consisting only of fiber bundles. The second wrappers are all made of paper with good air permeability, and the outermost wrapper connecting the filter part and the tobacco part is made of air-impermeable chip paper. At this time, a chip paper bag with holes pre-drilled so that the vent hole is located above the filter part made only of fibers is used, but after wrapping with chip paper without vent holes, holes are punched above the filter part made only of fiber bundles. It's okay. Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of a filtered cigarette using the filter of the present invention, and FIG. 2 is a sectional view of a commercially available filtered cigarette used in a comparative experiment. In FIG. 1, A is a filter portion in which the hollow tube 1 is arranged in the center of the fiber bundle 2 on the mouthpiece side, B is a filter portion consisting only of the fiber bundle 6 on the tobacco side, and 7 is a filter portion provided at the portion of the fiber bundle 6 on the tobacco side. The vent holes shown are shown below. C is the tobacco part. 3 is a primary wrapper made of porous paper, which wraps the mouthpiece side fiber bundle 2 and the tobacco part side fiber bundle 6, respectively. 4 is a secondary wrapper made of perforated paper, which connects and wraps the filter parts A and B. Reference numeral 5 denotes a chip paper which is an outer peripheral covering paper and serves as an air-impermeable exterior member, and connects and wraps the tobacco portion C and the filter portions A and B. FIG. 3 schematically shows how air and smoke flow when smoking a cigarette using the filter of the present invention. Together with the air a flowing in from the tip of the tobacco part C and the air b flowing through the wrapping paper 8 of the tobacco part C,
When the tobacco smoke flowing from the tobacco section C toward the smoker's mouth passes through the filter section B, it passes through the vent hole 7.
It partially merges with the dilution air C flowing in from the fiber bundle 6 and is influenced by it, producing a portion diagonally crossing the longitudinal direction of the tobacco portion side fiber bundle 6. In addition, since the inside of the hollow tube 1 of the filter portion A has much lower ventilation resistance than the surrounding area, smoke in the center of the filter portion B gathers in the center and reaches the oral cavity through the hollow tube 1. Smoke in the periphery of the filter part B passes through the mouth-side fiber bundle 2 in the periphery of the filter part A and reaches the oral cavity. As a result, from the filter portion A, smoke d with a low degree of filtration and rich taste flows into the central portion, and smoke d with a high degree of filtration flows into the peripheral portion into the smoker's oral cavity. As a result, it is possible to reduce the outflow of tar and nicotine as a whole while satisfying the smoker's requirements for flavor. In the filter of the present invention, most of the filtration of tar and nicotine is performed in filter section B. Considering that the length of the filter tip of a standard cigarette with a filter currently on the market is 17 mm, the length of the filter part B is 5 to 5 mm.
15mm is appropriate. On the other hand, the appropriate length of the filter part A is 10 to 20 mm, and the length of the entire filter tip is 15 to 35 mm.
mm is appropriate. Further, the hollow tube 1 installed in the filter portion A preferably has an inner diameter of 0.3 to 3.5 mm. If the hollow tube 1 has an inner diameter smaller than this range, a sufficient amount of smoke will not pass through the tube, resulting in insufficient flavor, and if the diameter is too large, the filtration function of the filter as a whole will be reduced. When the filter of the present invention is disassembled after being used for smoking, a large amount of tar is adsorbed not only in the filter part B but also at the boundary between the filter part A and the filter part B, and is also deposited inside the hollow tube 1. A feature of the filter of the present invention is that the ratio of tar delivery to nicotine delivery is small, and it is thought that the tar deposition mechanism as described above is involved. In the filter of the present invention, the filaments in filter portion A must be thicker than the filaments in filter portion B (preferably, the filaments are separated by 1.5 denier or more). The reason for this is that if the ventilation resistance is simply adjusted by changing the packing density of tow in the filter parts A and B, the absolute value of the outflow amount can be reduced, but the difference in flavor (nicotine/tar ratio)
There is a problem. That is, if the filaments in the filter part A are the same as or finer than those in the filter part B, too much smoke will collect inside the hollow tube 1, causing unnecessarily strong stimulation and causing a strange sensation. Since the filament in filter portion A is thicker than that in filter portion B, smoke also flows into the peripheral filament portions of filter portion A.
The smoke d is further filtered and reaches the oral cavity inside the hollow tube 1.
can eliminate the negative effects of overconcentration. Examples and Comparative Examples As an example, a cellulose acetate crimped fiber bundle with a total denier of 43,000 denier, which is a Y-shaped cross-sectional bundle of 4-denier filaments, was used as the fiber bundle 2 on the suction side of the filter portion A, and a hollow fiber made of vinyl chloride resin was used. Using tube 1 (inner diameter 1 mm, 2 mm, 3 mm), a filter plug with hollow tube 1 placed in the center was prepared and cut into a length of 15 mm. Also, the cross-sectional shape Y
A cellulose acetate crimped fiber bundle with a total denier of 40,000 denier, which is made by bundling filaments with a thickness of 2.2 denier, is used as the tobacco part side fiber bundle 6 of filter part B, and a filter plug with a homogeneous structure is created by the usual method. It was cut to a length of 10 mm.
After joining these two parts with perforated paper 4, the cigarette part C wrapped with commercially available cigarette paper 8 is joined using tip paper 5, and vent holes 7 are made in the filter part B, and the vent holes 7 are made with a needle. Six locations were installed. A smoking taste test was conducted using the filtered cigarette prepared by the above method to evaluate the filtration characteristics of the filter and the aroma and taste. As a comparative example, as shown in Fig. 2, a filter part D was prepared by bundling 4-denier filaments with a Y-shaped cross section and wrapping a fiber bundle 6 with a total denier of 43,000 denier with a 25-mm perforated paper 3. Similar to the example, commercially available cigarettes E wrapped in wrapping paper 8 are placed in the filter section D.
A smoking taste test was conducted using a filter connected with Tip Paper 5 without a vent hole, and the filtration characteristics of the filter and the evaluation of the aroma and taste were measured. Incidentally, the total denier of 43,000 denier is 10,750 filaments (4 denier). The above-mentioned taste test was conducted using a ventilation meter described in Japanese Utility Model Publication No. 56-31326 to measure the dilution rate. This ventilation meter is
A sample cigarette is stored in a cylindrical holder, and 17.5ml/SEC of air is sucked in from the mouthpiece of the cigarette, and the inside of the cigarette is extracted from the top (the tip of the cigarette), the column (the rolled up part of the cigarette), and the side of the filter. Measure the amount of air flowing into the The results are shown in Table 1.

[Table] In Table 1, the definitions of measurement items and measurement methods are as follows. Air inflow amount (%): When sucking at a flow rate of 17.5 ml/sec at the suction port, the amount of air flowing in from the top (a), air flowing in from the column (b), and air flowing in from the vent hole 7 (c). The percentage is shown in %. Airflow resistance: Airflow resistance through filter portions A and B when suction was carried out at a flow rate of 17.5 ml/sec was indicated using a scale of a water column meter. Tar, nicotine, delivery amount: constant flow constant time automatic smoker
17.5ml/sec
Number of puffs: once per minute, duration of one puff: 2 seconds (35ml),
The tar and nicotine in the smoke that passed through the filter was removed using glass fiber filter paper (Cambridge).
filter)
The amount of tar was measured gravimetrically, and the amount of nicotine was measured using liquid chromatography. Tar, nicotine, filtration rate: The amount of tar and nicotine collected by the filter and the amount of tar and nicotine collected by the Cambridge filter were measured by the above method and calculated using the following formula. Filtration rate (%) = amount collected in tobacco filter /
Amount collected in the Cambridge filter + amount collected in the tobacco filter x 100 Nicotine/tar ratio (delivery): Shows the amount of tar and nicotine in the same sample collected in the Cambridge filter in weight ratio. Ta. The above characteristic values are the average values of three measurements, each using a separate sample. The tar and nicotine filtration rate when using the filter of the present invention was higher than that of the comparative example, and showed the ability to selectively remove tar rather than nicotine. Separately, a flavor test was conducted by 20 panelists, and 18 people answered that the Example had a better flavor and taste compared to the Comparative Examples, and 2 people answered the opposite.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a filter-equipped cigarette using the filter of the present invention, and FIG. 2 is a cross-sectional view of a commercially available filter-equipped cigarette. FIG. 3 is a schematic diagram of how air and smoke flow when smoking a cigarette using the filter of the present invention. A: hollow tube installed filter part, B...fiber filter part, C: tobacco part, 1: hollow tube, 2: mouthpiece side fiber bundle, 3: porous paper (primary wrapper), 4:
Porous paper (secondary wrapper), 5: Outer covering paper (chip paper), 6: Tobacco part side fiber bundle, 7: Vent hole, 8: Wrapping paper, a: Air flowing in from the tip of the cigarette, b: Through the cigarette wrapping paper incoming air,
c: Air flowing in from the vent hole, d: Smoke entering the oral cavity.

Claims (1)

[Claims] 1 A tobacco part side fiber bundle, a mouthpiece side fiber bundle that is provided on the mouthpiece side of the tobacco part side fiber bundle, and is arranged in the center of the mouthpiece side fiber bundle and a mouthpiece side fiber bundle that is made of fibers thicker than the fibers of the tobacco part side fiber bundle. a hollow tube made of air-impermeable material;
A cigarette filter characterized in that an air-impermeable exterior member that encloses a tobacco part side fiber bundle and a mouthpiece side fiber bundle is provided with a vent hole provided in a portion of the tobacco part side fiber bundle.