Cigarette filter stick and low-temperature cigarette

Abstract

The invention relates to a cigarette filter stick and a low-temperature cigarette. The cigarette filter stick comprises a tow filter element and packaging paper, the tow filter element comprises a first hollow tow filter section, and the first end of the first hollow tow filter section makes contact with a user; the first end of the second tow filter section is connected with the second end of the first hollow tow filter section, the second tow filter section is made of polylactic acid fiber tows, and the fiber cross section of the polylactic acid fiber tows is Y-shaped or circular; the first end of the third tow filter section is connected with the second end of the second tow filter section, and the second end of the third tow filter section is used for being connected with a tobacco shred section. The diacetate fiber tows or the polypropylene fiber tows are compounded with the polylactic acid fiber tows, so that the heat dissipation effect and the cooling effect of the material are improved, smoke is kept smooth, the roundness, the hardness and the suction resistance stability of the filter tip can be guaranteed, and the taste is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of low-temperature cigarettes, and in particular to a cigarette filter rod and a low-temperature cigarette having the cigarette filter rod. Background Art

[0002] Cigarette filter is the most important component of cigarettes besides tobacco. As a filter material for cigarettes, in addition to good processability, it also has the following characteristics: (1) The processed filter rod is non-toxic, odorless, and meets food grade standards; (2) It has appropriate rigidity and curling performance, good fluffiness and opening performance, and the filter rod can meet the requirements of circumference, hardness, and suction resistance; (3) The stability of the filament bundle is good and can meet the requirements of filter rod forming equipment and process; (4) During the smoking process, the filament bundle in the filter does not shrink when heated and the filter does not deform; (5) It has high adsorption and filtration performance for harmful components in smoke.

[0003] At present, the main materials for cigarette filters are diacetate fiber tow and polypropylene fiber tow. Polypropylene is a completely crystalline polymer with a stable structure and no polar groups. The tow surface is smooth, the adsorption performance is poor, and the spicy taste is heavy. It can only be used in low-end cigarettes. With the improvement of people's living standards and health and environmental protection requirements, it has basically withdrawn from the market in my country and is mainly used in Southeast Asian cigarette markets such as Vietnam and Laos.

[0004] Diacetate fiber tow is a filter material with good performance and widely used at home and abroad. The raw materials come from high-quality wood (such as eucalyptus) grown for many years. Dry solution spinning is used to produce tows of different specifications. The domestic production generally adopts the technology of developed countries such as Celanese, Eastman and Daicel of Japan. The polymer chain of diacetate fiber tow contains strong polar groups such as -OH, and the surface of the tow has micropores. Therefore, diacetate fiber tow has adsorption and filtration effects on harmful components of smoke. Triacetin is added for bonding during the molding process, and the filter rod meets the requirements of hardness, circumference and suction resistance. However, the raw material of diacetate fiber tow is high-quality wood grown for many years, which mainly relies on imports. At the same time, acetone is required as a solvent in the production of wood pulp, esterification of cellulose and spinning of diacetate fiber tow. The production process is more dangerous and seriously pollutes the environment, resulting in high production costs. In addition, compared with polylactic acid fiber, its biodegradability is poor, and it takes several years to degrade. It will cause certain pollution to the environment after being discarded.

[0005] Polylactic acid is a biopolymer material made from renewable plant resources (corn, cassava) or straw cellulose (corn cobs and plant straw, etc.) using modern biofermentation technology to make lactic acid, which is then polymerized. It has good biodegradability and recyclability, is safe and environmentally friendly, and meets the sustainable development requirements of the domestic and international communities. Polylactic acid has good processability, uses melt spinning, has low energy consumption, and does not cause any pollution to the environment. The surface of polylactic acid fiber has discontinuous horizontal stripes and grooves, and contains polar groups (ester groups) in the molecules. It has a strong adsorption and filtration effect on harmful components in smoke, and is a suitable material for cigarette filters. Compared with the development and application of textile materials, the development of polylactic acid fiber tow as a cigarette filter material in China is relatively slow, and there are few reports on the large-scale application of polylactic acid fiber tow in cigarette filter materials. Therefore, the development of polylactic acid fiber tow filter rods is of great significance.

[0006] In terms of the development of filter materials for cigarettes, in 2014, Philip Morris, the world's largest traditional tobacco producer, launched the heat-not-burn electronic cigarette IQOS. The filter uses a composite rod, and the middle section uses a polylactic acid film for cooling, which solves the pain point of the unreal taste of e-cigarettes with e-liquid, and quickly occupies the market. In 2017, Philip Morris's new cigarettes accounted for 10% of its market share. 4.7 million users worldwide have completely converted from traditional cigarettes to IQOS users. At present, the proportion of American smokers turning to new cigarettes exceeds 13%. New tobacco has caused a boom at home and abroad and has become the latest development direction and trend of tobacco. However, due to the low crystallinity and poor temperature resistance of polylactic acid film, the film quickly melts and sticks when it contacts high-temperature smoke during the suction process, resulting in a blocked smoke channel and a sharp drop in smoke volume, affecting the taste. At the same time, polylactic acid film has the characteristics of brittleness and hardness, and cannot guarantee the stability of the roundness, hardness and suction resistance of the filter, and cannot be easily formed like traditional tow, affecting the taste of cigarettes and the appearance of the filter. Summary of the invention

[0007] In order to solve the above technical problems existing in the prior art, the present invention provides a cigarette filter rod.

[0008] In a first aspect, the present invention provides a cigarette filter rod, which comprises a tow filter element and a wrapping paper covering the tow filter element, wherein the tow filter element comprises:

[0009] a first hollow fiber tow filter segment, wherein a first end of the first hollow fiber tow filter segment is configured to contact a user;

[0010] a second tow filter segment, wherein a first end of the second tow filter segment is connected to a second end of the first hollow tow filter segment, wherein the second tow filter segment is made of a polylactic acid fiber tow, and a fiber cross-sectional shape of the polylactic acid fiber tow is Y-shaped or circular;

[0011] A third tow filter segment, wherein the first end of the third tow filter segment is connected to the second end of the second tow filter segment, and the second end of the third tow filter segment is used for connecting shredded tobacco.

[0012] In some embodiments, a single fiber of the polylactic acid fiber tow is a single-component structure or a core-sheath bicomponent structure.

[0013] In some embodiments, the linear density of the polylactic acid fiber tow is 1.1ktex-4.4ktex, for example, 1.3ktex, 1.5ktex, 1.7ktex, 2.0ktex, 2.1ktex, 2.3ktex, 2.5ktex, 2.7ktex, 3.0ktex, 3.1ktex, 3.3ktex, 3.5ktex, 3.7ktex, 4.0ktex or 4.2ktex. In some embodiments, the linear density of the polylactic acid fiber tow is 1.7ktex-3.3ktex. In some embodiments, the linear density of the polylactic acid fiber tow is 2.0ktex-2.4ktex.

[0014] In the present invention, the linear density of the polylactic acid fiber tow is the total linear density of the tow.

[0015] In some embodiments, the preparation method of the polylactic acid fiber tow includes a pre-spinning step and a post-spinning step, wherein the pre-spinning step includes drying, melting, spinning and winding the first polylactic acid slice and the modifier masterbatch to obtain the spun fiber; wherein the modifier masterbatch includes the second polylactic acid slice and the modifier, and the modifier is selected from titanium dioxide;

[0016] The post-spinning step includes sequentially subjecting the primary fibers to bundling treatment, oil immersion treatment, drafting treatment, water bath treatment, and hot water ironing treatment to obtain intermediate fibers, and sequentially subjecting the intermediate fibers to curling treatment, relaxation heat setting treatment, and packaging treatment, wherein the temperature of the hot water ironing treatment is 60°C-90°C.

[0017] In some embodiments, the temperature of the hot water ironing treatment is 61°C, 62°C, 63°C, 64°C, 65°C, 66°C, 67°C, 68°C, 69°C, 70°C, 71°C, 72°C, 73°C, 74°C, 75°C, 76°C, 77°C, 78°C, 79°C, 80°C, 81°C, 82°C, 83°C, 84°C, 85°C, 86°C, 87°C, 88°C, 89°C or any value therebetween. In some embodiments, the temperature of the hot water ironing treatment is 70°C-80°C.

[0018] In some embodiments, based on the mass of the modifier masterbatch, the mass content of the modifier is 20%-55%. In some embodiments, the mass content of the modifier is 22%, 25%, 27%, 30%, 33%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 46%, 48%, 50%, 53% or any value therebetween. In some embodiments, the mass content of the modifier is 35%-45%.

[0019] In some embodiments, based on the mass content of the first polylactic acid slice, the mass content of the modifier masterbatch is 0.4%-0.8%. In some embodiments, the mass content of the modifier masterbatch is 0.43%, 0.45%, 0.47%, 0.51%, 0.53%, 0.55%, 0.57%, 0.59%, 0.60%, 0.61%, 0.63%, 0.65%, 0.67%, 0.69%, 0.71%, 0.73%, 0.75%, 0.77% or any value therebetween. In some embodiments, the mass content of the modifier masterbatch is 0.5%-0.7%.

[0020] In some embodiments, in the pre-spinning step, the moisture content of the first polylactic acid slice after drying is less than 0.05‰. In some embodiments, in the pre-spinning step, the moisture content of the modifier masterbatch after drying is less than 0.05‰.

[0021] In some embodiments, the temperature of the first polylactic acid chip drying process is 90° C.-110° C., for example, 93° C., 95° C., 97° C., 99° C., 100° C., 103° C., 105° C. or 107° C. In some embodiments, the temperature of the first polylactic acid chip drying process is 95° C.-105° C.

[0022] In some embodiments, the first polylactic acid slice is dried for 3 hours to 12 hours, for example, 4 hours, 6 hours, 8 hours or 10 hours. In some embodiments, the first polylactic acid slice is dried for 5 hours to 9 hours.

[0023] In some embodiments, the temperature of the drying process of the modifier masterbatch is 90°C-110°C, for example, 93°C, 95°C, 97°C, 99°C, 100°C, 103°C, 105°C or 107°C. In some embodiments, the temperature of the drying process of the modifier masterbatch is 95°C-103°C.

[0024] In some embodiments, the time for drying the modifier masterbatch is greater than or equal to 24 hours. In some embodiments, the time for drying the modifier masterbatch is 25 hours to 40 hours.

[0025] In some embodiments, in the pre-spinning step, the melt treatment is carried out in a screw extruder. In some embodiments, during the melt treatment, the screw temperature is 220°C-250°C, for example, 223°C, 225°C, 227°C, 230°C, 233°C, 235°C, 237°C, 240°C, 243°C, 245°C or 247°C. In some embodiments, the screw temperature is 225°C-240°C.

[0026] In some embodiments, in the pre-spinning step, the spinning process is performed in a spinning beam.

[0027] In some embodiments, the spinning process includes filtering and spinning the melt after the melt treatment. In some embodiments, during the spinning process, the spinning manifold temperature is 210°C-240°C, for example, 213°C, 215°C, 217°C, 220°C, 223°C, 225°C, 227°C, 230°C, 233°C, 235°C or 237°C. In some embodiments, the spinning manifold temperature is 215°C-230°C.

[0028] In some embodiments, the number of holes of the spinneret used for spinning is 180-800 holes, for example, 200 holes, 250 holes, 300 holes, 350 holes, 400 holes, 450 holes, 500 holes, 550 holes, 600 holes, 650 holes, 700 holes or 750 holes.

[0029] In some embodiments, the spinneret hole shape is Y-shaped or circular.

[0030] In some embodiments, the winding speed of the winding process is 500m / min-1200m / min, for example, 600m / min, 700m / min, 800m / min, 900m / min, 1000m / min or 1100m / min. In some embodiments, the winding speed of the winding process is 600m / min-1000m / min.

[0031] In some embodiments, in the post-spinning step, the spun fibers are subjected to a bundling treatment before being subjected to an oil soaking treatment.

[0032] In some embodiments, in the post-spinning step, the temperature of the oil immersion treatment is less than or equal to 40° C. In some embodiments, in the post-spinning step, the temperature of the oil immersion treatment is 25° C.-35° C.

[0033] In some embodiments, in the post-spinning step, the drafting treatment is a waterbath drafting treatment. In some embodiments, the temperature during the drafting treatment is 60°C-80°C, for example, 65°C, 67°C, 70°C, 73°C, 75°C or 77°C. In some embodiments, the temperature during the drafting treatment is 62°C-75°C.

[0034] In some embodiments, the drafting ratio is 2.4 to 3.0 times.

[0035] In some embodiments, in the post-spinning step, the water bath treatment temperature is 70° C.-90° C., for example, 73° C., 75° C., 77° C., 79° C., 83° C., 85° C. or 87° C. In some embodiments, in the post-spinning step, the water bath treatment temperature is 75° C.-85° C.

[0036] In some embodiments, in the post-spinning step, during the crimping process, the crimping wheel diameter is 50 mm-100 mm, for example, 55 mm, 60 mm, 65 mm, 70 mm, 75 mm, 80 mm, 85 mm, 90 mm or 95 mm. In some embodiments, the crimping wheel diameter is 60 mm-80 mm.

[0037] In some embodiments, in the post-spinning step, during the crimping process, the crimping wheel width is 15 mm-30 mm, for example, 17 mm, 20 mm, 23 mm, 25 mm or 27 mm. In some embodiments, the crimping wheel width is 20 mm-28 mm.

[0038] In some embodiments, in the post-spinning step, the temperature of the relaxation heat setting treatment is 45°C-60°C, for example, 47°C, 50°C, 53°C, 55°C or 57°C. In some embodiments, the temperature of the relaxation heat setting treatment is 50°C-55°C.

[0039] In some embodiments, in the post-spinning step, the time of the relaxation heat setting treatment is 5 min-20 min, for example, 7 min, 9 min, 10 min, 13 min, 15 min or 17 min. In some embodiments, the time of the relaxation heat setting treatment is 10 min-15 min.

[0040] In some embodiments, the method for preparing the polylactic acid fiber tow comprises the following specific steps:

[0041] The pre-spinning step includes drying the polylactic acid slices and the modifier masterbatch respectively, and then simultaneously inputting the melted polylactic acid slices and the modifier masterbatch into the screw and the spinning box to filter and spin the fibers through the components, and then winding and dropping the fibers into the barrel to obtain the primary fibers;

[0042] The post-spinning step includes the steps of oil soaking, water bath drawing, hot water bath, hot water ironing, curling, relaxation and heat setting, and packaging to obtain the finished polylactic acid fiber bundle after the primary fiber is bundled.

[0043] In some embodiments, the first hollow fiber tow filter segment is made of diacetate fiber tow or polypropylene fiber tow, preferably diacetate fiber tow.

[0044] In some embodiments, the third tow filter segment is made of diacetate fiber tow or polypropylene fiber tow, preferably diacetate fiber tow.

[0045] In some embodiments, the wrapping paper includes cigarette paper and plug wrapping paper, and the plug wrapping paper is in contact with the tow filter element.

[0046] In a second aspect, the present invention provides a cigarette comprising the cigarette filter rod according to the first aspect and a tobacco shred segment connected to the cigarette filter rod.

[0047] In some embodiments, the cigarette is selected from low-temperature cigarettes.

[0048] The beneficial effects of the present invention are:

[0049] The polylactic acid fiber tow composite filter rod provided by the present invention is composited with diacetate fiber tow or polypropylene fiber tow and polylactic acid fiber tow, and is cleverly designed with solid and hollow filter rod shapes, so that the composite filter rod has a large space and a small suction resistance, improves the heat dissipation and cooling effects of the material, maintains smooth smoke, and at the same time, ensures the roundness, hardness and suction resistance of the filter tip, as well as the stability of the smoking taste. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 Schematic diagram of the structure of cigarette filter rods in some embodiments of the present invention; wherein, 1-first hollow fiber filter segment; 2-second fiber filter segment; 3-third fiber filter segment; 4-cigarette paper; 5-molding paper. DETAILED DESCRIPTION

[0051] The following will describe the implementation methods of the present invention in detail with reference to the accompanying drawings and embodiments, so that the implementation process of how the present invention applies technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly. It should be noted that as long as there is no conflict, the various embodiments of the present invention and the various features in the embodiments can be combined with each other, and the technical solutions formed are all within the protection scope of the present invention.

[0052] In the present invention, the polylactic acid fiber tow is prepared by the following method:

[0053] 1. Pre-spinning steps

[0054] Raw material drying: The polylactic acid chips were dried at 95°C for 9 hours; the modifier masterbatch (a blend of polylactic acid chips and titanium dioxide, in which the titanium dioxide content is 40%) was weighed according to 0.6% of the amount of polylactic acid chips and dried at 95°C for 30 hours. After drying, the moisture content of the polylactic acid chips was 0.03‰, and the moisture content of the modifier masterbatch was 0.045‰.

[0055] Screw melting and spinning box assembly filtering and spinning: The dried polylactic acid slices and modifier masterbatch are simultaneously transported to the screw extruder for heating and melting, and the melt is filtered and spun through the assembly in the spinning box to form primary fibers. The screw temperature during heating and melting is 235°C and the spinning box temperature is 226°C; the spinneret has 320 holes, and the spinneret hole shape is Y-shaped.

[0056] Winding and dropping into barrel: the nascent fiber is wound by a traction machine and a feeding machine and sent into a fiber barrel, and the winding speed is 1000m / min.

[0057] 2. Post-spinning steps

[0058] Bunching, oiling, drawing, water bathing, ironing: Bunching the nascent fibers obtained by spinning is followed by oiling, water bath drawing, hot water bathing, and hot water ironing to improve physical and mechanical properties and obtain better curling effects. The oiling temperature is 31°C; the water bath drawing temperature is 70°C, the drawing multiple is 2.75 times; the hot water bath temperature is 80°C; and the hot water ironing temperature is 75°C.

[0059] Crimping, relaxation heat setting, and packaging: the fibers after hot water ironing are sent to the crimping machine for crimping, and then dried in the relaxation heat setting machine and packaged to obtain a polylactic acid fiber tow with a single-filament linear density of 8.89 dtex and a total linear density of 2.22 ktex. The crimping wheel used for the crimping has a diameter of 80 mm and a width of 20 mm; the relaxation heat setting temperature is 52°C and the time is 12 minutes.

[0060] like Figure 1 As shown, the cigarette filter rod proposed in the present invention includes: a tow filter element and a wrapping paper covering the tow filter element, the tow filter element includes a first hollow tow filter segment 1, the first end of the first hollow tow filter segment 1 is used to contact with a user; a second tow filter segment 2, the first end of the second tow filter segment 2 is connected to the second end of the first hollow tow filter segment 1; a third tow filter segment 3, the first end of the third tow filter segment 3 is connected to the second end of the second tow filter segment 2, and the second end of the third tow filter segment is used to connect a tobacco segment.

[0061] Wherein, the first hollow fiber bundle filter segment is made of diacetate fiber bundle.

[0062] The second tow filter segment is made of polylactic acid fiber tow, and the cross-sectional shape of the polylactic acid fiber tow used is Y-shaped, so as to achieve the purpose of cooling the smoke while better adsorbing and filtering the smoke.

[0063] The third tow filter segment is made of diacetate fiber tow.

[0064] The wrapping paper comprises cigarette paper 4 and plug-in paper 5, and the plug-in paper 5 is in contact with the tow filter element.

[0065] Although the present invention has been described in detail above with general descriptions and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements may be made thereto based on the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection claimed by the present invention.

Claims

1. A cigarette filter rod, comprising a tow filter element and a wrapping paper covering the tow filter element, wherein the tow filter element include: a first hollow fiber tow filter segment, wherein a first end of the first hollow fiber tow filter segment is configured to contact a user; a second tow filter segment, wherein a first end of the second tow filter segment is connected to a second end of the first hollow tow filter segment, wherein the second tow filter segment is made of a polylactic acid fiber tow, and a fiber cross-sectional shape of the polylactic acid fiber tow is Y-shaped or circular; A third tow filter segment, wherein the first end of the third tow filter segment is connected to the second end of the second tow filter segment, and the second end of the third tow filter segment is used to connect to a tobacco shred segment.

2. The cigarette filter rod according to claim 1, It is characterized in that The individual fibers of the polylactic acid fiber bundle are of a single-component structure or a core-sheath type two-component structure.

3. The cigarette filter rod according to claim 1 or 2, It is characterized in that The linear density of the polylactic acid fiber bundle is 1.1 ktex-4.4 ktex, preferably 1.7 ktex-3.3 ktex, and more preferably 2.0 ktex-2.4 ktex.

4. The cigarette filter rod according to any one of claims 1 to 3, It is characterized in that The preparation method of the polylactic acid fiber bundle comprises a pre-spinning step and a post-spinning step, wherein the pre-spinning step comprises drying, melting, spinning and winding the first polylactic acid slice and the modifier masterbatch to obtain the nascent fiber; wherein the modifier masterbatch comprises the second polylactic acid slice and the modifier, and the modifier is selected from titanium dioxide; The post-spinning step includes sequentially subjecting the primary fibers to bundling treatment, oil immersion treatment, drafting treatment, water bath treatment, and hot water ironing treatment to obtain intermediate fibers, and sequentially subjecting the intermediate fibers to curling treatment, relaxation heat setting treatment, and packaging treatment, wherein the temperature of the hot water ironing treatment is 60°C-90°C.

5. The cigarette filter rod according to claim 4, It is characterized in that The temperature of the hot water ironing treatment is 70°C-80°C.

6. The cigarette filter rod according to claim 4 or 5, It is characterized in that Based on the mass of the modifier masterbatch, the mass content of the modifier is 20%-55%, preferably 35%-45%; and / or Based on the mass content of the first polylactic acid chips, the mass content of the modifier masterbatch is 0.4%-0.8%, preferably 0.5%-0.7%.

7. The cigarette filter rod according to any one of claims 1 to 6, It is characterized in that The first hollow fiber bundle filter segment is made of diacetate fiber bundle or polypropylene fiber bundle, preferably made of diacetate fiber bundle.

8. The cigarette filter rod according to any one of claims 1 to 7, It is characterized in that The third tow filter segment is made of diacetate fiber tow or polypropylene fiber tow, preferably made of diacetate fiber tow.

9. The cigarette filter rod according to any one of claims 1 to 8, It is characterized in that The wrapping paper includes cigarette paper and plug-in paper, and the plug-in paper is in contact with the tow filter element.

10. A low-temperature cigarette, comprising the cigarette filter rod according to any one of claims 1 to 9 and a tobacco shred segment connected to the cigarette filter rod.

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