JPH0474995B2 - - Google Patents

Description

[Detailed description of the invention]

[Technical Field] The present invention relates to a ventilation type cigarette filter that has low ventilation resistance during smoking and is easy to smoke. [Prior Art] In recent years, due to changes in smoking tastes, there has been a demand for the development of cigarettes that have a lighter smoking sensation with less suction resistance.To achieve this purpose, various tobacco filters have been developed. Research and development is underway. To achieve this objective, we have developed a cigarette filter that improves its overpower characteristics to achieve low tar and nicotine content, and introduces external air into the cigarette or filter through the tobacco cylinder or tobacco filter to reduce tobacco smoke. Many diluting products have been developed and each has been put into practical use. Things that can improve the characteristics of tobacco filters include increasing the amount of material filled in the tobacco filter, making the fibers that make up the tobacco filter finer, and increasing their specific surface area to improve the adsorption rate of tar and nicotine. Tobacco filters have been developed in which the fibers that make up the tobacco filter are arranged in a densely arranged structure and the excess area is increased, but the former two have a high suction resistance when smoking, The disadvantage is that the resulting cigarette has a poor smoking sensation. On the other hand, when the cigarette paper is made breathable and outside air is introduced into the cigarette silicone during smoking, the tobacco smoke is diluted by the outside air and the amount of tobacco smoke generated is reduced, resulting in a lower smoking sensation and a faster start of smoking. The amount of dilution air increases, making it light but not enough, but this effect drops off significantly at the end of the puff, resulting in a harsh sucking taste with a large amount of smoke. Cigarette filters that have holes in part of the paper (chip paper) and let air in through the holes are thought to be able to produce preferable cigarettes with less change in taste during smoking, but they are not currently used. In order to keep the overefficiency of tar and nicotine constant, the acetate plain filter used as a filter has a ventilation resistance (CORESTA STANDARD).
METHOD No. 10, September 1968)) has been required to be 50 mmH ₂ O or more, so a filter wrapped with chip wrapping paper with holes reduces the amount of smoke passing through the filter. On the other hand, the disadvantages that the amount of ventilation air is excessive, resulting in a bad smoking taste, and the cigarette has a large change in smoking sensation from the beginning to the end of the cigarette, have not been improved in any way. To overcome these difficulties, a type of cigarette filter has been developed in which a groove space is provided between the cigarette filter body and the wrapping paper, and ventilation air is allowed to flow through this groove space (Special Publication No. 57-1983).
29146, 57−29147, 57−29148, 56−31948, 58−
32955, Japanese Unexamined Patent Publication No. 59-11170, and Japanese Utility Model Application Publication No. 55-17429). The main purpose of a tobacco filter with these groove spaces is to separate the flow of tobacco smoke and ventilation air that have passed through the filter, and to mix the tobacco smoke and ventilation air for the first time in the mouth, thereby improving the taste of smoking. However, the drawback that the feeling of smoke increases as smoking progresses and the smoke taste is strong has not been improved in any way, and the development of a cigarette that has a nearly constant smoke taste between the start and end of smoking is not possible. It is held. [Purpose of the Invention] Therefore, the inventors of the present invention aimed to create a cigarette that has a small difference in taste between the beginning and end of smoking, has low suction ventilation resistance, has a good smoking feeling, and has an appropriate overefficiency of tar and nicotine. We are currently considering developing a cigarette filter that can achieve this goal, and have confirmed that this goal can be achieved by creating a dual-structure filter that combines two filter plugs with special characteristics, and have developed the present invention. completed. [Structure of the Invention] The gist of the present invention is that the length is on the mouth side.
Consisting of a cylindrical aggregate of cellulose diacetate fibers with a length of 12.5 mm or more and an airflow resistance of less than 25 mm H ₂ O as shown by the differential pressure between both ends of the filter when air is passed through the filter at 17.5 ml/sec. A first filter plug wrapped with high-porosity wrapping paper with an air permeability of 1300 ml/min.cm ² .10 cm H ₂ O or more is placed on the tobacco side, and a second filter plug with an air ventilation resistance of 25 mm H ₂ O or more is placed on the tobacco side. These are placed at an air permeability of 1300ml/min・cm ²・10cmH ₂ O (between the front and back sides of the wrapping paper).
Dual paper with a high porosity (amount of air permeated per unit area, unit time) when air is passed through so as to generate a pressure difference of 10mmH ₂ O, and a chip paper that has holes in it. The dual structure cigarette filter is characterized in that a tip wrapper is wrapped around the first filter plug part so that the first filter plug part is disposed on the first filter plug part. The present invention will be explained below with reference to the drawings. An example of a side sectional view of the dual structure cigarette filter of the present invention connected to a cigarette is shown in FIG. After passing through the unburned tobacco section 1, the tobacco smoke 10 passes through the second high airflow resistance filter section 2 and the first low airflow resistance filter section 3 before reaching the smoker's mouth. On the other hand, the ventilation air 11 is
The air permeability is 1300 ml/min・cm ²・10 cmH ₂ O or more, which is used when dualizing the first filter plug and the second filter plug, entering through the opening 9 of the tip wrapping paper 8 of the first filter plug part. It passes through the high air permeability wrapping paper (hereinafter the same applies) 7 and the high air permeability wrapping paper 6 of the first low air resistance filter, flows along the inner outer periphery of the low air resistance filter section 3, and reaches the smoker's mouth. The first low air resistance filter section 3 needs to have a length of 12.5 mm or more so that the openings 9 of the tip wrapping paper 8 are not covered by the lips even during smoking. The ventilation resistance of the first low ventilation resistance filter section 3 is set to 25mmH ₂ O.
In order to make the fiber diameter less than 1, it is necessary to thicken the fibers constituting the filter, and it is preferable to use fibers with a single fiber fineness of 7 deniers or more, more preferably 15 deniers or more. The apparent thickness of the fibers constituting the first filter is more important than the actual thickness, and from this point of view, it is more preferable if the fibers are hollow. The second image shows an enlarged electron microscope photograph (350x) of hollow fibers that can be effectively used to make the first low air permeability filter.
Shown in the figure. The air permeability of the first low air resistance filter is required to be less than 25 mm H ₂ O. When using a dual-structure filter in which the first low air resistance filter is combined with the second high air resistance filter, the first filter is a filter with an air permeability of 50 mm H ₂ O, which is used as a normal commercial cigarette filter. When smoking, the wrapping paper with perforations allows too much ventilation air to be taken into the mouth due to the high ventilation resistance of the filter, and the flow of smoke into the mouth due to the tobacco cylinder is large. As a result, it is impossible to obtain a cigarette with a good smoking taste. In contrast, the air permeability of the first filter was set to 25 mm.
The filter used in the present invention, which is less than H ₂ O and has holes in the wrapping paper, can balance the inflow of ventilation air during suction with the flow rate of smoke from the tobacco cylinder, so it is suitable for practical use. Even though the amount of smoke taken into the mouth is small, it is possible to produce a cigarette with a good smoke feel. Also, the air permeability of the paper wrapping around the first filter is
It is necessary that the flow rate is 1300ml/min.cm ² .10cmH ₂ O or more. If the first filter is wrapped with wrapping paper with a lower air permeability and is also wrapped with perforated tip paper, the intake of ventilation air into the first filter is insufficient, and the intake resistance is large, inhibiting the feeling of smoking. This is not preferable because it will appear as if the Cigarettes equipped with only the first filter having the above-described structure are not only undesirable because they have a poor filtering efficiency for tar and nicotine during smoking, but also increase the feeling of smoke as the smoking progresses, giving a feeling of smoking. Changes greatly. This tendency is due to the fact that with filtered cigarettes using perforated tip wrapping paper, the amount of ventilation air inhaled through the openings of the tip wrapping paper decreases as the ventilation resistance of the cigarette cylinder decreases as smoking progresses. This further increases the disadvantageous effects mentioned above. In order to improve these inconveniences, in the present invention, a high ventilation resistance filter with ventilation resistance of 25 mmH ₂ O or more is arranged on the cigarette cylinder side, and a low ventilation resistance filter with openings in the tip paper is arranged on the mouthpiece side. This objective was achieved by installing a filter. By placing a high air permeability filter with an air permeability of 25 mmH ₂ O or more on the cigarette cylinder side, the suction resistance of the cigarette cylinder part at the start of smoking and at the end of smoking can be averaged out for the entire filtered cigarette. The amount of smoke introduced into the mouth through the filter is averaged at the beginning and end of smoking, so
It is possible to produce a cigarette that always gives a good smoking feeling. A wrapping paper that is wrapped around the outside of the cellulose diacetate fibers to form a cylindrical fiber mass during the manufacture of the first filter, and a wrapping paper that is used to combine the first filter and the second filter to form a dual structure filter. Air permeability is 1300ml/min.
It is necessary to have a high porosity of cm ² ·10 mmH ₂ O or more. The air permeability of the two wrapping papers wrapped around the outside of the first filter is 1300ml/min・cm ²・10mmH ₂
If the temperature is less than
This is not preferable because the amount of water taken into the filter decreases and the suction resistance increases. The fibers constituting the first filter used in carrying out the present invention are cellulose diacetate fibers. The reason why it is necessary to use cellulose diacetate fibers as the fibers of the first filter is that the taste of the smoke that has passed through the first filter is
This is because the aroma and flavor of smoke are superior to the taste of smoke that has passed through a filter made of other fiber materials. As mentioned above, the feature of the second filter is that it equalizes the feeling of smoke volume at the beginning and end of the cigarette, and is not greatly influenced by the excessive characteristics of the overfill material. As the constituent fibers, cellulose diacetate fibers, rayon fibers, polypropylene fibers, etc. can be used, but when the taste is particularly taken into consideration, cellulose diacetate fibers are preferably used as the material of the second filter. Furthermore, the wrapping paper for the second filter plug can be either a low air resistance wrapping paper or a high air ventilation resistance wrapping paper, but the wrapping paper that connects the first filter and the second filter is the wrapping paper that is attached to the bench of the first filter. In order to efficiently exhibit the rayon effect, it is necessary to use wrapping paper with high air permeability. In addition, it is necessary to use low-air permeability paper for the chip wrapping paper that connects the tobacco filter and the tobacco cylinder in order to efficiently exhibit the filter characteristics and the ventilation effect on the first filter. The dual-structure cigarette filter of the present invention has a second filter plug with high airflow resistance placed on the cigarette side to produce low-tar smoke, and almost the center of the first filter with low airflow resistance placed on the mouth side. Since the smoke is passed through and sent into the mouth while suppressing the deterioration of the smoking taste as much as possible, smoke with a good smoking taste is sent into the mouth. On the other hand, ventilation air enters through the openings in the chip wrapping paper, and
The structure is such that the ventilation air passes through the outside of the filter section without mixing much with the smoke that passes through the center, and most of the ventilation air mixes with the smoke in the mouth at once, making this effect more efficient. In order to achieve good performance, it is necessary to use a high porosity wrapping paper with an air permeability of 1300 ml/min・cm ²・10 cmH ₂ O or more as the first filter plug wrapping paper, and as a chip wrapping paper, it is necessary to use a wrapping paper with a high air permeability of 1300 ml/min・cm 2 ・10 cmH 2 O or more. It is necessary to use a chip wrapper with perforations as shown in FIG. The tip wrapping paper may have holes in advance, or a method may be used in which the holes are formed after the filter is attached to the cigarette. The present invention will be explained in more detail with reference to Examples below. Example First, a commonly used cigarette paper was used, with a single fiber fineness of 7.5 denier and a fiber cross-sectional shape of Y.
The cross section is made of cellulose diacetate fiber tow with a total fineness of 36,000 denier and a circumference of 24.7 mm and a length of 75 mm.
This plug was used as a cigarette cylinder substitute 1 used to measure the suction characteristics of a cigarette filter. Next, air permeability 1300ml/min・cm ²・10
A similar plug was molded from cmH ₂ O high porosity wrapping paper and used as Tobacco Cylinder Substitute 2. The ventilation resistance measured by these closed ventilation resistance measurement methods was 98 mmH ₂ O in all cases. Apart from this, a, b of Table 1, sample number 2
We made a cigarette filter with an air permeability of 30,000ml/
A dual paper with a high porosity of min.cm ² .10 cmH ₂ O was connected to cigarette cylinder substitute 1 using a perforated chip paper with an opening area of 6 mm mm ² to obtain sample A for measuring the total dilution rate. . Here, the wrapping paper of cigarette filter a has an air permeability of 30,000ml/min・cm ²・10cm
H ₂ O ultra-high porosity wrapping paper was used, and the opening point of the chip wrapping paper was set at 12.5 mm from the mouth end. In addition, we use cellulose diacetate fiber tow with a single fiber fineness of 2.2 denier, a Y-shaped fiber cross-section, and a total fineness of 40,000 denier.
Air permeability 24.7mm, length 25mm cigarette filter
It was rolled up with high porosity wrapping paper of 30,000 ml/min.cm ² .10 cmH ₂ O, and connected to tobacco cylinder substitute 1 using a perforated chip wrapping paper with an aperture area of 6 mm mm ² to obtain Sample B for measuring the total dilution rate. As before, the opening point was set 12.5 mm from the mouth side edge. Next, the air permeability was set to 30,000 ml/min・cm ²・10 cmH ₂ O using the tobacco filter shown in JP-A-59-11170.
A tobacco filter made of high porosity wrapping paper with a circumference of 24.7 mm and a length of 25 mm was connected to tobacco cylinder substitute 1 in the same manner as in the former case, and was used as sample C for measuring the total dilution rate. Next, Tobacco Cylinder Substitute 1 of Total Dilution Rate Measurement Sample B was replaced with Tobacco Cylinder Substitute 2, and a non-perforated chip wrapping paper was used as Total Dilution Rate Measurement Sample D. The total air dilution ratio of these samples A to D was measured by varying the length of the tobacco substitute, and the results are shown in FIG. These results show that the filter with holes in the chip wrapping paper is better than the porous cigarette paper, and among the filters with holes in the chips, the low airflow resistance type filter of the present invention has the greatest change in air dilution rate. It can be seen that there are few Next, Samples 1 to 3 shown in Table 1 were created.
Here, the filters a and b, and the wrapping paper when dualizing these, have an air permeability of 30,000 ml/
It was a high porosity wrapping paper of min.cm ² .10cmH ₂ O, and the filter c used ordinary wrapping paper. In addition, the opening point was set 12.5 mm from the mouth side edge. Table 1
The total TPM, total tar, and
The reduction rate and smoke intake relative to the total nicotine, the N/T (100 times the ratio of nicotitanium and tar), and the air dilution rate are shown. FIG. 4 shows changes in the ventilation resistance of cigarettes when the aperture area of Samples 1 to 3 was changed. These results show that the filter of the present invention enables cigarettes with low ventilation resistance and good smoking sensation, and also has a selection function that allows more nicotine to pass through than tar in samples using hollow fibers. I understand. Here, the ventilation resistance is the value of the pressure loss in water column when air is passed through the filter at a rate of 17.5ml/sec, and the ventilation resistance of the cigarette is
The measurements were taken with an open type, and all other values are shown as values measured with a closed type. In addition, the smoking test used a constant flow type automatic smoker, with a flow rate of 17.5 ml/sec, smoking time of 2 seconds/time, and a smoking frequency of 1.
The test was conducted under the following conditions: smoke per minute, smoke volume: 35 ml/time, smoke length: 5 cm/piece. Further, the air dilution rate was expressed as the value obtained by dividing the amount of air flowing in from the tobacco cylinder portion or the perforated portion of the chip wrapper by the total suction air amount, and multiplying this by 100.

〔Effect of the invention〕

As is clear from Table 1, Figures 3 and 4,
The dual-structure cigarette filter of the present invention has low ventilation resistance during smoking, and enables low-tar cigarettes with little difference in taste as the smoking progresses.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of a dual structure tobacco filter of the present invention connected to a tobacco cylinder, FIG. 2 is an electron micrograph of a cross section of a large denier hollow cellulose diacetate yarn used in the present invention, and FIG. Figure 3 shows the change in total air dilution rate with change in length of the tobacco cylinder. FIG. 4 shows the effect of reducing ventilation resistance due to the openings of the dual-structure tobacco filter and the plain filter of the present invention. Symbols in Figure 1, 1...Tobacco cylinder part, 2
...High airflow resistance filter part, 3...Low airflow resistance filter part, 4...Cigarette wrapping paper, 5...High airflow resistance filter wrapping paper, 6...Low airflow resistance filter wrapping paper, 7...High airflow resistance when dualizing Porosity wrapping paper, 8... Chip wrapping paper, 9... Opening part, 10...
Tobacco smoke flow, 11... Ventilation air.

Claims (1)

[Claims] 1 The length on the mouth side is 12.5 mm or more, and the ventilation resistance shown by the differential pressure between both ends of the filter when air is passed through the filter at 17.5 ml/sec is 25
The filter, which is a cylindrical aggregate of cellulose diacetate fibers with less than mmH ₂ O, was
A first filter plug wrapped with high porosity wrapping paper with a ventilation resistance of 25mmH ₂ O or more is placed _on the tobacco side, and these are placed ⁱⁿ a 1300ml/min・cm ²・10cm
It is characterized in that it is dual-wrapped with high porosity wrapping paper of H ₂ O or more, and the chip wrapping paper is further wrapped so that the opening part of the chip wrapping paper having an opening is disposed in the first filter plug part. Dual structure cigarette filter.