阅读说明：本技术 一种可降低烟气温度的多元中空复合纤维丝束烟用滤棒 (Multi-element hollow composite fiber tow cigarette filter rod capable of reducing smoke temperature ) 是由 李明 袁俊武 于 2021-08-11 设计创作，主要内容包括：本发明公开了一种可降低烟气温度的多元中空复合纤维丝束烟用滤棒及其制备方法,旨在提供具有降温效果的卷烟滤棒；当无中段时,滤棒为二元复合滤棒,当中段为颗粒、爆珠或凝胶的醋纤滤棒的一种时,滤棒为三元复合滤棒；当中段为颗粒、爆珠或凝胶组成的的二元复合醋纤滤棒时,滤棒为四元复合滤棒；卷烟滤棒下端为分布均匀的圆柱形聚乳酸滤棒；滤棒中段为分布均匀的添加颗粒、爆珠或凝胶的醋纤滤棒,滤棒上端为中空的纸质滤棒、竹子纤维滤棒、棉质纤维滤棒、醋纤滤棒。本发明可以利用尺寸的缩小产生文丘里效应,起到降低烟气温度的作用,提升烟支抽吸时的舒适性与轻松感。(The invention discloses a multi-element hollow composite fiber tow cigarette filter stick capable of reducing smoke temperature and a preparation method thereof, aiming at providing a cigarette filter stick with a cooling effect; when the middle section is not provided, the filter stick is a binary composite filter stick, and when the middle section is one of granular, bead-blasting or gel acetate fiber filter sticks, the filter stick is a ternary composite filter stick; when the middle section is a binary composite acetate fiber filter stick consisting of particles, exploded beads or gel, the filter stick is a quaternary composite filter stick; the lower end of the cigarette filter stick is provided with a cylindrical polylactic acid filter stick which is uniformly distributed; the middle section of the filter stick is an acetate fiber filter stick which is evenly distributed and is added with particles, exploded beads or gel, and the upper end of the filter stick is a hollow paper filter stick, a bamboo fiber filter stick, a cotton fiber filter stick and an acetate fiber filter stick. The invention can generate the Venturi effect by utilizing the reduction of the size, plays a role in reducing the temperature of the smoke and improves the comfort and the ease feeling of smoking cigarettes.)

1. A multi-element hollow composite fiber tow cigarette filter stick capable of reducing smoke temperature is characterized by comprising: at least one section of upper end filter section close to the cigarette branch end and one section of lower end filter section close to the smoking end form a binary composite filter stick; or

A middle filter section is also arranged between the upper filter section and the lower filter section, and the middle filter section is a ternary composite filter rod formed by one of particles, exploded beads or gel; or

A composite middle section formed by particles or exploded beads and gel is also arranged between the upper end filter section and the lower end filter section to form a quaternary composite filter rod;

wherein: the upper end filter section and the lower end filter section are both hollow sections, and the upper end filter section is composed of one of a paper fiber filter stick, a bamboo fiber filter stick or a cotton fiber filter stick.

2. The filter rod for cigarette made of multi-element hollow composite fiber tows as claimed in claim 1, wherein the filter material of the lower filter segment is made of polylactic acid or acetate fiber tows, the filter material of the middle filter segment is made of acetate fiber filter rods or polylactic acid fibers, and the hollow cross-sectional area of the lower filter segment is smaller than that of the upper filter segment.

3. The filter stick for the multi-element hollow composite fiber tow cigarette according to claim 2, wherein the paper filter stick, the bamboo fiber filter stick or the cotton fiber filter stick of the upper end filter segment is prepared by the following process conditions: the drying temperature is 60-80 ℃, the melt spinning temperature is 200-220 ℃, the winding speed is 600-800m/min, the drafting temperature is 50-70 ℃, the drafting multiplying factor is 2.0-2.5, the curling temperature is 85-95 ℃, and the drying temperature is 60-80 ℃; and the thickness of the section wall of the upper filtering section is not less than 1 mm.

4. The filter stick for the multi-element hollow composite fiber tow cigarette according to claim 1, wherein the vertical section of the hollow part of the upper filter segment is in a conical structure with a wide upper part and a narrow lower part, and the narrowest end surface is not smaller than the hollow section area of the lower filter segment.

5. The filter rod for the multi-element hollow composite fiber tow cigarette according to claim 4, wherein the cross section of the hollow part of the upper filter segment is triangular.

6. The filter stick for cigarette made of multi-element hollow composite fiber tows as claimed in claim 3, wherein the cross-sectional shapes of the hollow parts of the upper filter segment and the lower filter segment are respectively one of circular, rectangular, square, trapezoid, pentagram, equiangular triangle, equiangular hexagon, rhombus, heart-shaped, polygon, Arabic numerals or English letters.

Technical Field

The invention relates to the technical field of cigarettes, in particular to a multi-element hollow composite fiber tow cigarette filter stick capable of reducing smoke temperature.

Background

The phenomenon that the smoke temperature is increased often appears along with the combustion cone gradually approaching the filter rod end at the cigarette smoking rear section, the consumption experience is influenced, part of cigarette consumers can feel that the lip end is scalded, the smoke temperature in the oral cavity is high, and the smoke has large irritation when flowing through the throat and the nasal cavity. In order to solve the problem of overhigh smoke temperature in the smoking process of cigarettes, the cigarette specification is changed in part of cigarette product designs, the limited cooling effect can be realized due to the reduction of the size of a filter stick, but the smoking resistance of the cigarettes is increased, so that the light smoking experience of consumers in the smoking process is influenced.

On the other hand, the current filter stick is not resistant to high temperature, and the problem that the end part of the filter stick is soft and deforms, the air flow velocity is reduced, and the consumer experience is influenced due to the bending often occurs under the high-temperature condition.

Therefore, how to fully utilize the design of materials and structures to develop a cigarette filter stick with the effect of reducing the smoke temperature and apply the cigarette filter stick to cigarettes is urgent need and trend of innovation and development of cigarettes.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provides a multi-element hollow composite fiber tow cigarette filter stick capable of reducing the smoke temperature and a preparation method thereof.

In order to solve the technical problems, the invention is realized by the following technical scheme:

a multi-element hollow composite fiber tow cigarette filter stick capable of reducing smoke temperature comprises: at least one section of upper end filter section close to the cigarette branch end and one section of lower end filter section close to the smoking end form a binary composite filter stick; or a middle filter section is also arranged between the upper filter section and the lower filter section, and the middle filter section is a ternary composite filter rod formed by one of particles, exploded beads or gel; or a composite middle section formed by particles or exploded beads and gel is also arranged between the upper end filter section and the lower end filter section to form a quaternary composite filter rod; wherein: the upper end filter section and the lower end filter section are both hollow sections, and the upper end filter section is composed of one of a paper fiber filter stick, a bamboo fiber filter stick or a cotton fiber filter stick.

Furthermore, the filter material of the lower filter segment is composed of polylactic acid or acetate fiber tows, the filter material of the middle filter segment is composed of acetate fiber filter rods or polylactic acid fibers, and the hollow cross-sectional area of the lower filter segment is smaller than that of the upper filter segment.

Further, the paper filter stick, the bamboo fiber filter stick or the cotton fiber filter stick of the upper end filter segment is prepared by the following process conditions: the drying temperature is 60-80 ℃, the melt spinning temperature is 200-220 ℃, the winding speed is 600-800m/min, the drafting temperature is 50-70 ℃, the drafting multiplying factor is 2.0-2.5, the curling temperature is 85-95 ℃, and the drying temperature is 60-80 ℃; and the thickness of the section wall of the upper filtering section is not less than 1 mm.

Furthermore, the vertical section of the hollow part of the upper end filter section is of a conical structure with a wide upper part and a narrow lower part, and the narrowest end surface is not smaller than the hollow section area of the lower end filter section.

Further, the cross section of the hollow part of the upper filter segment is triangular.

Further, the cross-sectional shapes of the hollow parts of the upper filter segment and the lower filter segment are respectively one of a circle, a rectangle, a square, a trapezoid, a pentagram, an equiangular triangle, an equiangular hexagon, a rhombus, a heart, a polygon, an Arabic number or an English letter.

The working principle and the advantages of the invention are introduced: the invention discloses a multi-element hollow composite fiber tow cigarette filter stick capable of reducing smoke temperature and a preparation method thereof, and aims to provide a cigarette filter stick with a cooling effect. Wherein, one end of the filter stick facing to the cigarette is called as an upper end, one end close to the smoking end is a lower end, and the part of the filter stick in the middle of the lower end of the upper end is a middle section; when the middle section does not exist, the invented filter stick is a binary composite filter stick, and when the middle section is one of granular, bead-blasting or gel acetate fiber filter sticks, the invented filter stick is a ternary composite filter stick; when the middle section is a binary composite acetate fiber filter stick of particles, exploded beads or gel, the filter stick is a quaternary composite filter stick. The upper end of the cigarette filter stick is provided with a cylindrical polylactic acid filter stick which is uniformly distributed; the middle section of the filter stick is an acetate fiber filter stick which is evenly distributed and is added with particles, exploded beads or gel, and the lower end of the filter stick is a hollow paper filter stick, a bamboo fiber filter stick, a cotton fiber filter stick and an acetate fiber filter stick. The invention can generate Venturi effect by reducing the size, plays a role in reducing the temperature of smoke and improves the comfort of smoking cigarettes. The preparation process of the paper fiber, bamboo fiber or cotton fiber tow comprises the following steps: the drying temperature is 60-80 ℃, the melt spinning temperature is 200-220 ℃, the winding speed is 600-800m/min, the drafting temperature is 50-70 ℃, the drafting multiplying factor is 2.0-2.5, the curling temperature is 85-95 ℃, and the drying temperature is 60-80 ℃. The fiber material prepared in the way is an environment-friendly material, has the characteristic of high temperature resistance, is low in cost, can not soften paper fiber, bamboo fiber or cotton fiber tows under the condition of continuously keeping high temperature, can still keep good hardness, can keep certain air permeability while keeping hardness and modeling stability, can effectively generate the Venturi effect by matching with a hollow structure to achieve the effect of firstly reducing the temperature of smoke, can intensively pass through effective filtering materials such as particles, exploded beads or gel and the like when passing through a middle filtering section, then enters a hollow area of a lower section again to generate the Venturi effect again, quickly and further reduces the temperature of the smoke, has just proper suction resistance, also has proper temperature of the smoke, and improves the overall suction feeling of heating non-combustible smoke by matching with the effect of high hardness, the quality is improved.

The tow provided by the invention has high production efficiency, the tow can be formed by adopting glyceryl triacetate for a filter stick, the bonding fastness is good, the temperature resistance of the filter stick is good, the forming process flow is consistent with that of an acetate fiber tow, the forming speed is high (about 300m/min), the production efficiency of the filter stick is high, the industrial and large-scale production is easy to realize, and the manufactured cigarette and the cigarette with the acetate fiber filter stick have no obvious difference in the release amount of harmful components and the sensory quality. Meanwhile, the cigarette external filter stick can pass through the filter stick with the reduced aperture when smoke flows through, and the change of the aperture can cause a Venturi effect, namely the temperature of the smoke is continuously reduced, and the smoking experience can be improved due to the reduction of the temperature of the smoke. The multi-element hollow composite filter stick can reduce the suction resistance due to the use of the hollow section, and can improve the ease of smoking of a user. The polylactic acid tow provided by the invention has wide original source and low cost, and the equipment required by the processing technology is basically the same as the traditional acetate fiber tow processing equipment.

Drawings

Figures 1 to 7 are longitudinal views of a hollow composite filter rod according to the invention.

Figure 8 is a schematic of the structure of a filter rod and cigarette of the present invention.

FIG. 9 is a flow chart of the polylactic acid tow spinning production process.

FIG. 10 is a schematic view of a three-dimensional structure of a multi-element hollow composite fiber tow cigarette filter rod with a circular cross section;

FIG. 11 is a schematic view of a three-dimensional structure of a filter rod for a multi-element hollow composite fiber tow cigarette, the cross section of which is triangular and pentagonal;

FIG. 12 is a schematic view of a planer structure of a multi-element hollow composite fiber tow cigarette filter rod;

FIG. 13 is a schematic view of a three-dimensional structure of a filter rod for a multi-element hollow composite fiber tow cigarette, the cross section of which is pentagonal and hexagonal;

wherein: 1-a polylactic acid fiber tow filter stick at the upper port, 2-8-polylactic acid fiber tow filter sticks with various cross-sectional shapes, 9-a lower end hollow filter stick, 10-a tobacco stick section, 11-a middle section filter section, 12-an upper end filter section, 13-a lower end filter section and 14-a hollow part

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without inventive effort based on the embodiments of the present invention, are within the scope of the present invention.

Fig. 1 is a process route diagram for preparing a paper fiber, bamboo fiber or cotton fiber tow filter stick.

The preparation process of the paper fiber, bamboo fiber or cotton fiber tow comprises the following steps: the drying temperature is 60-80 ℃, the melt spinning temperature is 200-220 ℃, the winding speed is 600-800m/min, the drafting temperature is 50-70 ℃, the drafting multiplying factor is 2.0-2.5, the curling temperature is 85-95 ℃, and the drying temperature is 60-80 ℃. The prepared fiber material is an environment-friendly material, has the characteristic of high temperature resistance, is low in cost, and can keep good hardness and certain air permeability while keeping hardness and shape stability because paper fibers, bamboo fibers or cotton fiber tows cannot be softened under the condition of continuously keeping high temperature

The filter stick for the multi-element hollow composite fiber tow cigarette capable of reducing the smoke temperature shown in figure 1 comprises a polylactic acid fiber tow filter stick 1 at the upper end opening and a polylactic acid fiber tow filter stick 2 with a circular section.

Fig. 2 shows a multi-component hollow composite fiber tow cigarette filter stick capable of reducing smoke temperature, which comprises a polylactic acid fiber tow filter stick 1 at an upper port and a polylactic acid fiber tow filter stick 3 with a rectangular section.

Fig. 3 shows a multi-component hollow composite fiber tow cigarette filter stick capable of reducing smoke temperature, which comprises a polylactic acid fiber tow filter stick 1 at the upper port and a polylactic acid fiber tow filter stick 4 with a square cross section.

Fig. 4 shows a multi-component hollow composite fiber tow cigarette filter stick capable of reducing smoke temperature, which comprises a polylactic acid fiber tow filter stick 1 at an upper port and a polylactic acid fiber tow filter stick 5 with a trapezoidal section.

Fig. 5 shows a multi-component hollow composite fiber tow cigarette filter stick capable of reducing smoke temperature, which comprises a polylactic acid fiber tow filter stick 1 at the upper port and a polylactic acid fiber tow filter stick 6 with a pentagram cross section.

Fig. 6 shows a multi-component hollow composite fiber tow cigarette filter stick capable of reducing smoke temperature, which comprises a polylactic acid fiber tow filter stick 1 at the upper port and a polylactic acid fiber tow filter stick 7 with an equiangular triangle section.

Fig. 7 shows a multi-component hollow composite fiber tow cigarette filter stick capable of reducing smoke temperature, which comprises a polylactic acid fiber tow filter stick 1 at the upper port and a polylactic acid fiber tow filter stick 8 with an equiangular hexagonal section.

Fig. 8 shows a cigarette prepared by the filter stick, which consists of a cigarette rod section 10 and a filter stick section, specifically, the filter stick consists of an upper end filter stick 12, a middle section filter stick 11 and a lower end hollow filter stick 9.

When a user sucks the smoke, the smoke flows through the upper end filter stick 12, the middle section filter stick 11 and the lower end hollow filter stick 9 and finally flows out, and the temperature of the flowing smoke is reduced.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Examples 1-6 are described for different tow making processes for the upper polylactic acid filter rods only.

Example 1

The preparation process of the paper fiber tow cigarette filter rod comprises the steps of drying at 60 ℃, melt spinning at 200 ℃, winding at 600m/min, drafting at 50 ℃, drafting multiplying power at 2.0, curling at 85 ℃ and drying at 60 ℃.

The paper fiber tow has good forming performance, and can be respectively used for preparing a paper fiber filter stick and a paper fiber lactic acid filter stick after being prepared.

Example 2

The preparation process of the filter stick for the cotton fiber tow cigarette comprises the steps of drying at 80 ℃, melt spinning at 220 ℃, winding at 800m/min, drafting at 70 ℃, drafting multiplying power at 2.5, curling at 95 ℃ and drying at 80 ℃.

The cotton fiber tow has good forming performance, and can be respectively used for preparing a cotton fiber filter stick and a hollow cotton fiber filter stick after being prepared.

Example 3

The preparation process of the filter stick for the bamboo fiber tow cigarette comprises the steps of drying at 70 ℃, melt spinning at 210 ℃, winding at 700m/min, drafting at 60 ℃, drafting multiplying power at 2.3, curling at 90 ℃ and drying at 70 DEG C

The bamboo fiber tow has good forming performance, and can be used for preparing a bamboo fiber filter stick and a hollow bamboo fiber filter stick respectively after preparing the fiber tow.

Example 4

The preparation process of the filter stick for the bamboo fiber tow cigarette comprises the steps of drying at 55 ℃, melt spinning at 190 ℃, winding at 500m/min, drafting at 45 ℃, drafting multiplying power at 1.8, curling at 80 ℃ and drying at 55 ℃.

The bamboo fiber tows have poor forming performance and can not be used for preparing filter sticks.

Example 5

The preparation process of the filter rod for the cotton fiber tow cigarette comprises the following steps: the drying temperature is 90 ℃, the melt spinning temperature is 230 ℃, the winding speed is 900m/min, the drafting temperature is 80 ℃, the drafting multiplying power is 3.0, the curling temperature is 100 ℃, and the drying temperature is 90 ℃.

The cotton fiber tow has poor forming performance and can not be used for preparing filter sticks.

Example 6

A binary hollow composite fiber tow cigarette filter rod is prepared by the steps of preparing a bamboo fiber tow filter rod at the upper end of the filter rod, wherein the drying temperature is 70 ℃, the melt spinning temperature is 210 ℃, the winding speed is 700m/min, the drafting temperature is 60 ℃, the drafting multiplying power is 2.3, the curling temperature is 90 ℃, the drying temperature is 70 ℃, the bamboo fiber tow forming performance is good, and the bamboo fiber filter rod and the hollow bamboo fiber filter rod are prepared by using the filter rod.

The smoke mouth-by-mouth temperature of the conventional cellulose acetate fiber cigarette and the multi-element hollow composite bamboo fiber filter stick (the section of the lower end is circular and hollow) cigarette in the ISO standard suction mode is measured by a thermocouple, and the smoke temperature of the binary hollow composite filter stick and the smoke temperature of the conventional cigarette are compared as shown in Table 1.

TABLE 1

The embodiment shows that the filter stick has obvious cooling effect on cigarettes of different specifications.

Example 7

The preparation process of the binary hollow composite fiber tow cigarette filter stick comprises the steps of drying at 70 ℃, melt spinning at 210 ℃, winding at 700m/min, drafting at 60 ℃, drafting multiplying power at 2.3, curling at 90 ℃ and drying at 70 DEG C

The paper fiber tow has good forming performance, and can be respectively used for preparing a paper fiber filter stick and a hollow paper fiber filter stick after being prepared.

The smoke mouth-by-mouth temperature of the conventional acetate fiber cigarette and the binary hollow composite paper fiber filter stick (the lower end section of the rectangular hollow) cigarette in the ISO standard suction mode is measured by using a thermocouple, and the comparison between the smoke temperature of the binary hollow composite filter stick and the smoke temperature of the conventional cigarette is shown in Table 2.

TABLE 2

The embodiment shows that the filter stick has obvious cooling effect on cigarettes of different specifications.

Example 8

The preparation process of the binary hollow composite cotton fiber tow cigarette filter stick comprises the steps of drying at 70 ℃, melt spinning at 210 ℃, winding at 700m/min, drafting at 60 ℃, drafting multiplying power at 2.3, curling at 90 ℃, and drying at 70 DEG C

The cotton fiber tow has good forming performance, and can be respectively used for preparing a cotton fiber filter stick and a hollow polylactic acid filter stick after being prepared.

The smoke mouth-by-mouth temperature of the conventional acetate fiber cigarette and the binary hollow composite cotton fiber filter stick (the lower end section of the square hollow) cigarette in the ISO standard suction mode was measured by a thermocouple, and the comparison between the smoke temperature of the binary hollow composite filter stick of the present invention and the smoke temperature of the conventional cigarette is shown in Table 3.

TABLE 3

The embodiment shows that the filter stick has obvious cooling effect on cigarettes of different specifications.

Example 9

The preparation process of the filter rod for the binary hollow composite fiber tow cigarette comprises the steps of drying at 70 ℃, melt spinning at 210 ℃, winding at 700m/min, drafting at 60 ℃, drafting multiplying power at 2.3, curling at 90 ℃ and drying at 70 ℃.

The polylactic acid tow has good forming performance, and polylactic acid filter rods can be respectively prepared as lower-end filter rods after the fiber tow is prepared. And respectively selecting a paper filter stick, a bamboo fiber filter stick, a cotton fiber filter stick and an acetate fiber filter stick as upper end filter sticks. The smoke mouth-by-mouth temperature of the conventional cellulose acetate fiber cigarette and the binary hollow composite filter rod (the lower end of which is circular in section) cigarette in the ISO standard suction mode is measured by using a thermocouple, and the comparison between the smoke temperature of the binary hollow composite filter rod and the smoke temperature of the conventional cigarette is shown in Table 8.

TABLE 8

The embodiment shows that the filter stick for the lower end cigarette made of different materials has obvious cooling effect on cigarettes with different specifications.

Example 10

The preparation process of the multi-element hollow composite fiber tow cigarette filter rod comprises the steps of drying at 70 ℃, melt spinning at 210 ℃, winding at 700m/min, drafting at 60 ℃, drafting multiplying power at 2.3, curling at 90 ℃, and drying at 70 ℃, wherein polylactic acid tows have good forming performance, and polylactic acid filter rods can be respectively prepared as lower-end filter rods after fiber tows are prepared.

Selecting a paper filter stick (the lower end of which is circular in section) as an upper end filter stick, and respectively adopting a gel filter stick, a particle filter stick, and a gel filter stick and particle filter stick combined section as a middle section filter stick. The thermocouple is used for measuring the smoke mouth-by-mouth temperature of the conventional acetate fiber cigarette and the gel filter rod ternary composite, the particle filter rod ternary composite and the gel and particle filter rod quaternary composite filter rod cigarette in the ISO standard suction mode, and the smoke temperature of the ternary and quaternary hollow composite filter rods and the smoke temperature of the conventional cigarette are compared as shown in the table 9.

TABLE 9

The embodiment shows that the cigarette with the gel filter rod ternary composite filter rod, the particle filter rod ternary composite filter rod and the gel and particle filter rod quaternary composite filter rod has obvious cooling effect on cigarettes with different specifications.

Example 11

A multi-element hollow composite fiber tow cigarette filter stick capable of reducing smoke temperature comprises: at least one section of upper end filter section close to the cigarette branch end and one section of lower end filter section close to the smoking end form a binary composite filter stick; and a middle filter section is also arranged between the upper filter section and the lower filter section, and is a granular filter rod, so that the ternary composite filter rod is integrally formed. The upper end filter section and the lower end filter section are both hollow sections, and the upper end filter section is a paper fiber filter stick.

Example 12

A multi-element hollow composite fiber tow cigarette filter stick capable of reducing smoke temperature comprises: at least one section of upper end filter section close to the cigarette branch end and one section of lower end filter section close to the smoking end form a binary composite filter stick; and a middle filter section is also arranged between the upper filter section and the lower filter section, and is an exploded bead filter rod, so that the ternary composite filter rod is integrally formed. The upper end filter section and the lower end filter section are both hollow sections, and the upper end filter section is a bamboo fiber filter stick.

Example 13

A multi-element hollow composite fiber tow cigarette filter stick capable of reducing smoke temperature comprises: at least one section of upper end filter section close to the cigarette branch end and one section of lower end filter section close to the smoking end form a binary composite filter stick; and a middle filter section is also arranged between the upper filter section and the lower filter section, and the middle filter section is a gel filter rod and integrally forms a ternary composite filter rod. The upper end filter section and the lower end filter section are both hollow sections, and the upper end filter section is a cotton fiber filter stick. The filter material of the lower filter segment is composed of polylactic acid fiber tows, the filter material of the middle filter segment is composed of acetate fiber filter sticks, and the hollow cross-sectional area of the lower filter segment is smaller than that of the upper filter segment.

Example 14

A multi-element hollow composite fiber tow cigarette filter stick capable of reducing smoke temperature comprises: at least one section of upper end filter section close to the cigarette branch end and one section of lower end filter section close to the smoking end form a binary composite filter stick; a middle filter section is also arranged between the upper filter section and the lower filter section, and the middle filter section is a composite middle section formed by particles or exploded beads and gel, so as to form a quaternary composite filter rod; wherein: the upper end filter section and the lower end filter section are both hollow sections, and the upper end filter section is a bamboo fiber filter stick.

The filter material of the lower end filter section is composed of acetate fiber tows, the filter material of the middle filter section is composed of polylactic acid fibers, and the hollow cross-sectional area of the lower end filter section is smaller than that of the upper end filter section.

Example 15

Examples 11 to 14 are also included. Preferably, the paper filter stick, the bamboo fiber filter stick or the cotton fiber filter stick of the upper end filter segment is prepared by the following process conditions: the drying temperature is 60-80 ℃, the melt spinning temperature is 200-220 ℃, the winding speed is 600-800m/min, the drafting temperature is 50-70 ℃, the drafting multiplying factor is 2.0-2.5, the curling temperature is 85-95 ℃, and the drying temperature is 60-80 ℃; and the thickness of the section wall of the upper filtering section is not less than 1 mm.

The vertical section of the hollow part of the upper end filtering section is of a conical structure with a wide upper part and a narrow lower part, and the narrowest end surface is not smaller than the hollow section area of the lower end filtering section. The cross section of the hollow part of the upper filter segment is triangular. Or the cross-sectional shapes of the hollow parts of the upper filter segment and the lower filter segment are respectively one of circular, rectangular, square, trapezoid, five-pointed star, equiangular triangle, equiangular hexagon, rhombus, heart, polygon, Arabic number or English letter.