Lyocell material, filter for smoking article, smoking article, and method of preparing the lyocell material

Abstract

The present application relates to a lyocell material, a filter for a smoking article, which includes the lyocell material, and a smoking article. The lyocell material and the filter for a smoking article, according to the present application, may replace cellulose acetate materials and filters for smoking articles including the same, in the art.

Description

Technical Field

[0001] The present application relates to a lyocell material, a filter including the same, a smoking article, and a method of preparing the lyocell material.Background Art

[0002] Until now, cellulose acetate fibers have been mainly used as tobacco filter materials. Cellulose acetate is known to be a biodegradable material, but filters for a smoking article, made of cellulose acetate, remain in their original form for 1 to 2 years even after being buried in soil, and it takes a considerable amount of time for the filters to completely biodegrade. Considering the amount and toxicity of tobacco products that are discarded and left in the living environment as well as tobacco products that are collected as waste after being used for smoking and then buried in a landfill, there is a need to further improve the biodegradability of filters for smoking articles. Accordingly, lyocell, which is more environmentally friendly, has recently been chosen as a material to replace cellulose acetate.Disclosure of InventionTechnical Problem

[0003] An object of the present application is to provide a lyocell material capable of replacing cellulose acetate commercialized for a filter for a smoking article.

[0004] Another object of the present application is to provide a lyocell material for a filter for a smoking article, of which a preparation process is environmentally friendly and which has excellent biodegradability when discarded.

[0005] Another object of the present application is to provide a lyocell filter for a smoking article.

[0006] Another object of the present application is to provide a smoking article (for example, a cigarette) including a lyocell filter.Solution to Problem

[0007] According to aspects of the present application, a lyocell material, a filter including the same, a smoking article, and the like may be provided.

[0008] According to an aspect, provided is a lyocell material including lyocell multifilaments to which crimps have been imparted, wherein the lyocell material has a filter process index (FPI) of 19 to 88, represented by Equation 1: 2 × CrE / Po wherein, in Equation 1, CrE is crimp energy, and Po is porosity represented by Equation 2 below: 1 − density A / density B × 100 wherein, in Equation 2, density A is an apparent density of the lyocell material, and density B is a true density of the lyocell material.

[0009] According to another aspect of the present application, a filter for a lyocell smoking article including the lyocell material may be provided.

[0010] According to another aspect of the present application, a smoking article including the lyocell material or the filter may be provided.

[0011] According to another aspect of the present application, a method of preparing the lyocell material, a filter including the same, and a smoking article may be provided.

[0012] As used herein, the term "smoking article" may refer to an article such as a tobacco (cigarette) or a cigar capable of generating aerosol. In this regard, the smoking article may include an aerosol-generating material or an aerosol-forming substrate. In addition, the smoking article may include a solid material based on a tobacco raw material such as a tobacco leaf, a cut tobacco, or a reconstituted tobacco. In addition, the smoking material may include a volatile compound.

[0013] As used herein, the term "crimp" or "crimped" may refer to the waviness, curliness, or undulating configuration imparted to materials such as fibers, (mono)filaments, multifilaments and / or yarns, inherently and / or through mechanical, thermal, or chemical processes. A crimp may be characterized by periodic deviations from a straight linear axis along the length of the material, fiber, (mono)filament, multifilament and / or yarn. One crimp of a material, fiber, (mono)filament, multifilament and / or yarn may be defined as one repetition unit of said periodic deviation. The presence of crimp contributes to properties such as elasticity, bulk, resilience, and texture in the material and fabrics made from it.

[0014] Unless specifically defined otherwise in the specification, when the properties of lyocell materials, filters for a smoking article, and components or compositions related thereto are affected by a temperature, the temperature at which the properties are confirmed or measured may be room temperature. In this case, the room temperature may be a temperature which is not particularly lowered or raised and may be, for example, in a range of 10 °C to 35 °C, specifically in a range of 15 °C to 35 °C or 20 °C to 30 °C, or may be about 25 °C.

[0015] Hereinafter, the present application is described in more detail.

[0016] The present application relates to a lyocell material. The lyocell material may be used in a smoking article, and although not particularly limited, the lyocell material may be used in a filter for a smoking article.

[0017] According to an aspect, provided is a lyocell material including lyocell multifilaments to which crimps have been imparted, wherein the lyocell material has an FPI of 19 to 88, represented by Equation 1. 2 × CrE / Po

[0018] In Equation 1, CrE is crimp energy, and Po is porosity represented by Equation 2 below. 1 − density A / density B × 100

[0019] In Equation 2, density A is an apparent density of the lyocell material, and density B is a true density of the lyocell material.

[0020] In some embodiments, the FPI may be in a range of 24 to 75.

[0021] In some embodiments, CrE in Equation 1 may be in a range of 400 mJ to 2,300 mJ.

[0022] In some embodiments, CrE in Equation 1 may be in a range of 550 mJ to 1,650 mJ.

[0023] In some embodiments, CrE in Equation 1 may be a value measured from a sample with a size of about 20 cm taken from a lyocell material by using a universal testing machine (UTM). Each sample was weighted until crimps were not identified. CrE may be a value obtained by converting, into energy, a weight added until a crimp is not identified from a sample. The expression "until a crimp is not identified from a sample" means that the waviness, curliness, or undulating configuration, as described above with regard to the term "crimp", is not shown by the sample anymore.

[0024] In some embodiments, Po in Equation 1 may be in a range of 15 % to 83 %.

[0025] In some embodiments, Po in Equation 1 may be in a range of 40 % to 70 %.

[0026] In some embodiments, density A in Equation 2 may be in a range of 0.300 g / cm 3< to 1.200 g / cm 3< .

[0027] In some embodiments, density A in Equation 2 may be in a range of 0.500 g / cm 3< to 0.900 g / cm 3< .

[0028] In some embodiments, density A in Equation 2 may be a value obtained by dividing a weight of a lyocell material by a volume of a container filled with the lyocell material. The shape of the container is not particularly limited. for example, the container may be box-shaped.

[0029] In some embodiments, density B in Equation 2 may be in a range of 1.40 g / cm 3< to 1.50 g / cm 3< .

[0030] In some embodiments, density B in Equation 2 may be in a range of 1.470 g / cm 3< to 1.490 g / cm 3< .

[0031] In some embodiments, density B in Equation 2 may be a value measured from a lyocell material by using a true specific density meter, in particular a pycnometer, under conditions in which gas for analysis is He (g), an equilibrium velocity is about 0.005 psig / min, an expansion volume is about 9.2169 cm 3< , and a cell volume is about 0.0029 g / cm 3< .

[0032] In some embodiments, the lyocell material may satisfy both Conditions 1 and 2 below.

[0033] [Condition 1] CrE in Equation 1 is in a range of 400 mJ to 2,300 mJ.

[0034] [Condition 2] Po in Equation 1 is in a range of 15 % to 83 %.

[0035] In some embodiments, the lyocell material may satisfy at least one of Conditions 1-1 and 2-1 below.

[0036] [Condition 1-1] CrE in Equation 1 is in a range of 550 mJ to 1,650 mJ

[0037] [Condition 2-1] Po in Equation 1 is in a range of 40 % to 70 %.

[0038] In some embodiments, the number of crimps may be 3.94 ea / cm (10 ea / inch) to 23.64 ea / cm (60 ea / inch).

[0039] In some embodiments, the number of crimps may be 9.85 ea / cm to 19.71 ea / cm (25 ea / inch to 50 ea / inch).

[0040] In some embodiments, a single fiber fineness of the lyocell multifilament may be in a range of 1.67 dtex to 12.21 dtex (1.5 denier to 11.0 denier).

[0041] In some embodiments, the single fiber fineness of the lyocell multifilament may be in a range of 2.22 dtex to 6.66 dtex (2.0 denier to 6.0 denier).

[0042] In some embodiments, the lyocell material may have a total fineness of1,667 tex to 6,111 tex (15,000 denier to 55,000 denier).

[0043] In some embodiments, the lyocell material may have a total fineness of 2,222 tex to 5,555 tex (20,000 denier to 50,000 denier).

[0044] In some embodiments, the lyocell multifilament may include one or more monofilaments, and one or more of the monofilaments may have a multi-lobal cross section.

[0045] In some embodiments, the lyocell multifilament may include one or more monofilaments, and all of the monofilaments may have a multi-lobal cross section.

[0046] In some embodiments, the lyocell material may be lyocell tow.

[0047] In some embodiments, the lyocell material may be used for a filter for a smoking article.

[0048] In some embodiments, the lyocell material may not not for use in tire cords or garments.

[0049] In some embodiments, the lyocell material may be a lyocell laminate.

[0050] In addition, according to another aspect, provided is a filter for a smoking article including any one of the lyocell materials described in this application.

[0051] Furthermore, according to another aspect, provided is a smoking article including any one of the filters for a smoking article described in this application.

[0052] In addition, provided is a method of preparing a lyocell material, which includes lyocell dope spinning; coagulating, and obtaining lyocell multifilament; washing; emulsion treatment; and crimp imparting, wherein the method further includes stacking and pressing, and an FPI measured from the lyocell material after the stacking and pressing is in a range of 19 to 88.

[0053] In some embodiments, a pressing pressure of the stacking and pressing may be in a range of 196 N / cm 2< to 588 N / cm 2< (20 kgf / cm 2< to 60 kgf / cm 2< ).

[0054] In some embodiments, a moisture content of the lyocell material measured before the crimp imparting may be in a range of 150 % to 400 %.

[0055] A lyocell material according to some embodiments may have an FPI of 19 to 88, represented by Equation 1 below. 2 × CrE / Po

[0056] In Equation 1, CrE is crimp energy, and Po is porosity represented by Equation 2 below. 1 − density A / density B × 100

[0057] In Equation 2, density A is an apparent density of the lyocell material, and density B is a true density of the lyocell material.

[0058] While researching the post-processing properties of a lyocell material, the applicants have found that the post-processing properties of the lyocell material depend on the crimp energy and porosity of the lyocell material and thus have found that the post-processing properties of the lyocell material may be adjusted by adjusting Equation 1 which includes crimp energy and porosity as variables. In particular, it has been confirmed that when an FPI is less than 19 or more than 88, the unwinding properties of the lyocell material may be significantly reduced.

[0059] Specifically, when an FPI is less than 19, the clumping of the lyocell material may occur during an unwinding process of the lyocell material, or the blooming of the lyocell material may not occur sufficiently during and / or after unwinding. As a result, the filterability of a filter for a smoking article including a lyocell material having an FPI of less than 19 may be insufficient. More specifically, a filter for a smoking article including a lyocell material having an FPI of less than 19 may have a maximum suction resistance of less than 400 mmHG / rod and may have filterability that is unsuitable for use as a filter for a smoking article.

[0060] Specifically, when the FPI exceeds 88, excessive energy may be required for opening and / or unwinding, and the opening and / or unwinding of the lyocell material may not be sufficiently performed. As a result, the cutting of the lyocell material may occur during an opening and / or unwinding process. In addition, the clumping of a lyocell material included in a filter for a smoking article may occur due to insufficient opening and / or unwinding, and the filter for a smoking article may burst due to the lyocell material.

[0061] Accordingly, the FPI represented by Equation 1 may be adjusted in a range of 19 to 88, thereby securing the processability of the lyocell material to a certain level or more. Furthermore, the filterability of a filter for a smoking article including the lyocell material may be implemented at a certain level or more.[Lyocell material]

[0062] According to an aspect, provided is a lyocell material including lyocell multifilaments to which crimps have been imparted, wherein the lyocell material has an FPI of 19 to 88, represented by Equation 1. 2 × CrE / Po

[0063] In Equation 1, CrE is crimp energy, and Po is porosity represented by Equation 2 below. 1 − density A / density B × 100

[0064] In Equation 2, density A is an apparent density of the lyocell material, and density B is a true density of the lyocell material.

[0065] Since the lyocell material satisfies Equation 1, the post-processing properties of the lyocell material, for example, unwinding properties, may be improved, and openability may be improved. As a result, process costs consumed to prepare a filter for a smoking article may be reduced.

[0066] Specifically, the lyocell material may be post-processed to be included in a filter for a smoking article. The post-processing may include unwinding the lyocell material and / or opening the lyocell material. In the case of a lyocell material of which an FPI represented by Equation 1 is not in a range of 19 to 88, the lyocell material may have insufficient unwinding properties and / or openability. For example, the lyocell material may not be unwound uniformly and continuously. As a result, a process of preparing a filter for a smoking article from a lyocell material may be delayed, and the filterability of a filter for a smoking article may be degraded.

[0067] In addition, the post-processing of the lyocell material may include applying an external force to the lyocell material to induce the blooming of the lyocell material. In the case of a lyocell material of which an FPI represented by Equation 1 is not in a range of 19 to 88, the blooming of the lyocell material may not occur smoothly.

[0068] More specifically, in the case of a lyocell material of which an FPI represented by Equation 1 is not in a range of 19 to 88, the lyocell material may be clumped or cut during an unwinding process of the lyocell material. In addition, the blooming of the lyocell material may not be performed uniformly due to the clumping of the lyocell material. As a result, the filterability of a filter for a smoking article may be degraded, or manufacturing thereof may become impossible, and a process of preparing a filter for a smoking article may be delayed or stopped.

[0069] In some embodiments, an upper limit of the FPI may be 85 or less, 82.5 or less, 80 or less, 77.5 or less, 75 or less, 72.5 or less, 70 or less, 67.5 or less, 65 or less, 62.5 or less, 60 or less, 57.5 or less, 55 or less, 52.5 or less, 50 or less, 47.5 or less, 45 or less, 42.5 or less, 40 or less, 37.5 or less, 35 or less, 32.5 or less, 30 or less, 27.5 or less, or 25 or less. By satisfying the upper limit of the FPI, the cutting of the lyocell material may be prevented, and the clumping of the lyocell material may be suppressed.

[0070] In addition, in some embodiments, a lower limit of the FPI may be 20 or more, 22.5 or more, 25 or more, 27.5 or more, 30 or more, 32.5 or more, 35 or more, 37.5 or more, 40 or more, 42.5 or more, 45 or more, 47.5 or more, 50 or more, 52.5 or more, 55 or more, 57.5 or more, 60 or more, 62.5 or more, 65 or more, 67.5 or more, 70 or more, or 72.5 or more. By satisfying the lower limit of the FPI, the unwinding defect of the lyocell material may be suppressed, and a filter for a smoking article including the same may provide filterability of a certain level or more (for example, a suction resistance of 400 mmHG / rod or more).

[0071] In some embodiments, the FPI may be in a range of 24 to 75. Preferably, the FPI may be in a range of 24 to 65, 24 to 60, 24 to 55, 24 to 50, 24 to 45, 24 to 40, 24 to 35, 24 to 30, 25 to 65, 30 to 65, 35 to 65, 40 to 65, 45 to 65,50 to 65, or 55 to 65, and more preferably 60 to 65.

[0072] In some embodiments, CrE in Equation 1 may be in a range of 400 mJ to 2,300 mJ. Since CrE satisfies such a numerical range, the filterability of a filter for a smoking article and the preparation processability of the filter for a smoking article may be harmoniously improved.

[0073] In some embodiments, an upper limit of CrE may be 2,200 mJ or less, 2,100 mJ or less, 2,000 mJ or less, 1,900 mJ or less, 1,800 mJ or less, 1,700 mJ or less, 1,600 mJ or less, 1,500 mJ or less, 1,400 mJ or less, 1,300 mJ or less, 1,200 mJ or less, 1,100 mJ or less, 1,000 mJ or less, 900 mJ or less, 800 mJ or less, 700 mJ or less, or 600 or less. Since the lyocell material satisfies the upper limit of CrE, the openability of the lyocell material may be improved, and the preparation processability of a filter for a smoking article including the lyocell material may be secured.

[0074] In some embodiments, a lower limit of CrE may be 500 mJ or more, 600 mJ or more, 700 mJ or more, 800 mJ or more, 900 mJ or more, 1,000 mJ or more, 1,100 mJ or more, 1,200 mJ or more, 1,300 mJ or more, 1,400 mJ or more, 1,500 mJ or more, or 1,600 or more. Since the lyocell material satisfies the lower limit of CrE, a filter for a smoking article including the same may provide filterability of a certain level or more (for example, a suction resistance of 400 mmHG / rod or more).

[0075] In some embodiments, CrE in Equation 1 may be in a range of 550 mJ to 1,650 mJ. Preferably, CrE may be in a range of 550 mJ to 1,600 mJ, 550 mJ to 1,500 mJ, 550 mJ to 1,400 mJ, 550 mJ to 1,300 mJ, 550 mJ to 1,200 mJ, 550 mJ to 1,100 mJ, 550 mJ to 1,000 mJ, 550 mJ to 900 mJ, 550 mJ to 800 mJ, 550 mJ to 700 mJ, 550 mJ to 600 mJ, 600 mJ to 1,600 mJ, 700 mJ to 1,600 mJ, 800 mJ to 1,600 mJ, 900 mJ to 1,600 mJ, 1,000 mJ to 1,600 mJ, 1,100 mJ to 1,600 mJ, 1,200 mJ to 1,600 mJ, 1,300 mJ to 1,600 mJ, or 1,400 mJ to 1,600 mJ, preferably 1,500 mJ to 1,600 mJ.

[0076] In each exemplary lyocell material, CrE in Equation 1 may be a value measured from a sample with a size of about 20 cm taken from a lyocell material by using a UTM, and CrE may be a value obtained by converting, into energy, a weight added until a crimp is not identified from a sample, as described above.

[0077] For example, Model No. 5566 manufactured by Intron Ltd., may be used as the UTM. In addition, an initial load applied to the sample may be about 0.98 N (100 gf).

[0078] In some embodiments, Po in Equation 1 may be in a range of 15 % to 83 %. Since Po satisfies such a numerical range, the unwinding properties of the lyocell material may be increased, and simultaneously, the cutting of the lyocell material may be prevented.

[0079] In some embodiments, an upper limit of Po may be 80 % or less, 78 % or less, 76 % or less, 74 % or less, 72 % or less, 70 % or less, 68 % or less, 66 % or less, 65 % or less, 64 % or less, 62 % or less, 60 % or less, 58 % or less, 56 % or less, 55 % or less, 54 % or less, 52 % or less, 50 % or less, 48 % or less, 46 % or less, 45 % or less, 44 % or less, or 42 % or less. Since Po satisfies the upper limit, the unwinding properties of the lyocell material may be improved, and the clumping of the lyocell material may be suppressed.

[0080] In some embodiments, a lower limit of Po may be 16 % or more, 18 % or more, 20 % or more, 22 % or more, 24 % or more, 26 % or more, 28 % or more, 30 % or more, 32 % or more, 34 % or more, 36 % or more, 38 % or more, 40 % or more, 42 % or more, 44 % or more, 46 % or more, 48 % or more, 50 % or more, 52 % or more, 54 % or more, 56 % or more, 58 % or more, 60 % or more, 62 % or more, 64 % or more, or 65 % or more. Since the lyocell material satisfies the lower limit of Po, the cutting of the lyocell material during an unwinding process may be suppressed. For example, by satisfying the lower limit of Po, the cutting of a lyocell monofilament due to tension may be suppressed.

[0081] In some embodiments, Po in Equation 1 may be in a range of 40 % to 70 %. Preferably, Po may be in a range of 40 % to 68 %, 40 % to 66 %, 40 % to 64 %, 40 % to 62 %, 40 % to 60 %, 40 % to 58 %, 40 % to 56 %, 40 % to 54 %, 40 % to 52 %, 40 % to 50 %, 40 % to 48 %, 40 % to 46 %, 40 % to 44 %, 40 % to 42 %, 42 % to 68 %, 44 % to 68 %, 46 % to 68 %, 48 % to 68 %, 50 % to 68 %, 52 % to 68 %, 54 % to 68 %, 56 % to 68 %, 58 % to 68 %, 60 % to 68 %, 62 % to 68 %, or 64 % to 68 %, or more preferably 66 % to 68 %.

[0082] In some embodiments, density A in Equation 2 may be in a range of 0.300 g / cm 3< to 1.200 g / cm 3< . In some embodiments, an upper limit of density A may be 1.150 g / cm 3< or less, 1.100 g / cm 3< or less, 1.050 g / cm 3< or less, 1.000 g / cm 3< or less, 0.950 g / cm 3< or less, 0.900 g / cm 3< or less, 0.850 g / cm 3< or less, 0.800 g / cm 3< or less, 0.750 g / cm 3< or less, 0.700 g / cm 3< or less, or 0.650 g / cm 3< or less. In some embodiments, a lower limit of density A may be 0.350 g / cm 3< or more, 0.400 g / cm 3< or more, 0.450 g / cm 3< or more, 0.500 g / cm 3< or more, 0.550 g / cm 3< or more, 0.600 g / cm 3< or more, 0.650 g / cm 3< or more, 0.700 g / cm 3< or more, 0.750 g / cm 3< or more, 0.800 g / cm 3< or more, or 0.850 g / cm 3< or more. Preferably, density A in Equation 2 may be in a range of 0.500 g / cm 3< to 0.900 g / cm 3< .

[0083] In some embodiments, density A in Equation 2 may be a value obtained by dividing a weight of a lyocell material by a volume of a container filled with the lyocell material. For example, the container may be a hexagonal box.

[0084] In some embodiments, density B in Equation 2 may be in a range of 1.40 g / cm 3< to 1.50 g / cm 3< . In some embodiments, an upper limit of density B may be 1.495 g / cm 3< or less, 1.490 g / cm 3< or less, 1.485, 1.480 g / cm 3< or less, or 1.475 g / cm 3< or less. In some embodiments, a lower limit of density B may be 1.405 g / cm 3< or more, 1.410 g / cm 3< or more, 1.415 g / cm 3< or more, 1.420 g / cm 3< or more, 1.425 g / cm 3< or more, 1.430 g / cm 3< or more, 1.435 g / cm 3< or more, 1.440 g / cm 3< or more, 1.445 g / cm 3< or more, 1.450 g / cm 3< or more, 1.455 g / cm 3< or more, 1.460 g / cm 3< or more, 1.465 g / cm 3< or more, 1.470 g / cm 3< or more, 1.475 g / cm 3< or more, or 1.480 g / cm 3< or more. Preferably, density B in Equation 2 may be in a range of 1.470 g / cm 3< to 1.490 g / cm 3< .

[0085] In some embodiments, density B in Equation 2 may be a value measured from a lyocell material by using a true specific density meter, for example a pycnometer, under conditions in which gas for analysis is He(g), an equilibrium velocity is about 0.005 psig / min, an expansion volume is about 9.2169 cm 3< , and a cell volume is about 0.0029 g / cm 3< .

[0086] In some embodiments, the lyocell material may satisfy both Conditions 1 and 2 below. By simultaneously satisfying Conditions 1 and 2, the FPI of the lyocell material may be in a range of 19 to 88.

[0087] [Condition 1] CrE in Equation 1 is in a range of 400 mJ to 2,300 mJ.

[0088] [Condition 2] Po in Equation 1 is in a range of 15 % to 83 %.

[0089] In some embodiments, the lyocell material may satisfy at least one of Conditions 1-1 and 2-1 below. By simultaneously satisfying Conditions 1-1 and 2-1, the FPI of the lyocell material may be in a range of 24 to 75.

[0090] [Condition 1-1] CrE in Equation 1 is in a range of 550 mJ to 1,650 mJ

[0091] [Condition 2-1] Po in Equation 1 is in a range of 40 % to 70 %.[Multi-lobal cross section]

[0092] One or more of lyocell monofilaments included in a lyocell material of the present application may have a multi-lobal cross section. The term "multi-lobal" may mean that a shape of an outline of a cross section is not circular, and the term "cross section" may be a cross section obtained by cutting a lyocell monofilament in a direction virtually or actually perpendicular to a longitudinal direction of a filament.

[0093] An outline of the multi-lobal cross section may touch each of an imaginary first circle and an imaginary second circle. In addition, the imaginary second circle may be depicted inside the imaginary first circle.

[0094] The imaginary first circle may be a circle with the smallest area value among circles drawn to completely encompass one cross section of a monofilament. The imaginary second circle may be a circle with the largest area value among circles drawn inside a cross section of a monofilament.

[0095] When a circumscribed circle encompassing a cross section of a monofilament may be drawn, the imaginary first circle may be the circumscribed circle. When an inscribed circle may be drawn inside a cross section of a monofilament, the imaginary second circle may be the inscribed circle.

[0096] The multi-lobal cross section may have a shape including a plurality of protrusions and may be, for example, a Y-shaped cross section including three protrusions. It may be understood that the plurality of protrusions are formed as an integral type with the imaginary second circle as a central portion and have a shape of which an end touches the imaginary first circle.

[0097] A modified ratio of a monofilament may be defined by Equation 1 below. Modified ratio = r 1 / r 2

[0098] Here, r1 is a radius of the imaginary first circle, and r2 is a radius of the imaginary second circle.

[0099] For example, the radius of the imaginary first circle may be in a range of 4 µm to 40 µm, the radius of the imaginary second circle may be in a range of 2 µm to 14 µm, and the modified ratio may be in a range of 1.01 to 10.

[0100] In addition, a space occupancy ratio of a monofilament may be defined by Equation 2. Space occupancy ratio = S 1 / S 2 × 100 %

[0101] Here, S1 is an area of the imaginary first circle, and S2 is a cross-sectional area of a monofilament included in lyocell fiber.

[0102] For example, a space occupancy ratio of a monofilament having a multi-lobal cross section may be in a range of about 120 % to about 600 %.[Fineness]

[0103] A lyocell material of the present application may include a lyocell multifilament, and the lyocell multifilament may have a fineness suitable for preparing a filter for a smoking article and securing a function thereof.

[0104] For example, a single fiber fineness of a filament constituting the lyocell multifilament may be in a range of 1.67 dtex to 12.21 dtex (1.5 denier to 11.0 denier). In this case, the single fiber fineness of the filament refers to a fineness of a single monofilament separated from a multifilament. In other words, the single fiber fineness of a filament constituting the lyocell multifilament refers to the monofilament fineness.

[0105] The single fiber fineness of the filament may be, for example, 11.66 dtex (10.5 denier) or less, 11.12 dtex (10.0 denier) or less, 10.55 dtex (9.5 denier) or less, 9.99 dtex (9.0 denier) or less, 9.44 dtex (8.5 denier) or less, 8.88 dtex (8.0 denier) or less, 8.33 dtex (7.5 denier) or less, 7.78 dtex (7.0 denier) or less, 7.22 dtex (6.5 denier) or less, 6.67 dtex (6.0 denier) or less, 6.11 dtex (5.5 denier) or less, 5.56 dtex (5.0 denier) or less, 5.00 dtex (4.5 denier) or less, 3.89 dtex (3.5 denier) or less, 3.33 dtex (3.0 denier) or less, or 2.78 dtex (2.5 denier) or less. A lower limit of the single fiber fineness of the filament may be, for example, 2.22 dtex (2.0 denier) or more, 2.78 dtex (2.5 denier) or more, 3.33 dtex (3.0 denier) or more, 3.89 dtex (3.5 denier) or more, 4.44 dtex (4.0 denier) or more, 5.00 dtex (4.5 denier) or more, 5.56 dtex (5.0 denier) or more, 6.11 dtex (5.5 denier) or more, 6.67 dtex (6.0 denier) or more, 7.22 dtex (6.5 denier) or more, or 7.78 dtex (7.0 denier) or more. Satisfying such a range may be more advantageous in securing stable physical properties (for example, implementing hardness or suction resistance) and processability of a filter for a smoking article.

[0106] In some embodiments, the total fineness of the lyocell material may be in a range of 1,667 tex to 6,111 tex (15,000 denier to 55,000 denier), and the total fineness of the lyocell material may be calculated as the sum of the finenesses of the lyocell monofilaments. For example, a lower limit of the total fineness may be, for example, 1,778 tex (16,000 denier) or more, 1,833 tex (16,500 denier) or more, 1,889 tex (17,000 denier) or more, 1,944 tex (17,500 denier) or more, 2,000 tex (18,000 denier) or more, 2,056 tex (18,500 denier) or more, 2,111 tex (19,000 denier) or more, 2,167 tex (19,500 denier) or more, 2,222 tex (20,000 denier) or more, 2,278 tex (20,500 denier) or more, 2,333 tex (21,000 denier) or more, 2,389 tex (21,500 denier) or more, 2,444 tex (22,000 denier) or more, 2,500 tex (22,500 denier) or more, 2,556 tex (23,000 denier) or more, 2,611 tex (23,500 denier) or more, 2,667 tex (24,000 denier) or more, 2,722 tex (24,500 denier) or more, 2,778 tex (25,000 denier) or more, 2,833 tex (25,500 denier) or more, 2,889 tex (26,000 denier) or more, 2,944 tex (26,500 denier) or more, 3,000 tex (27,000 denier) or more, 3,056 tex (27,500 denier) or more, 3,111 tex (28,000 denier) or more, 3,167 tex (28,500 denier) or more, 3,222 tex (29,000 denier) or more, 3,287 tex (29,500 denier) or more, 3,333 tex (30,000 denier) or more, 3,389 tex (30,500 denier) or more, 3,444 tex (31,000 denier) or more, 3,500 tex (31,500 denier) or more, 3,556 tex (32,000 denier) or more, 3,611 tex (32,500 denier) or more, 3,667 tex (33,000 denier) or more, 3,722 tex (33,500 denier) or more, 3,778 tex (34,000 denier) or more, 3,833 tex (34,500 denier) or more, 3,889 tex (35,000 denier) or more, 3,944 tex (35,500 denier) or more, 4,000 tex (36,000 denier) or more, 4,056 tex (36,500 denier) or more, 4,111 tex (37,000 denier) or more, 4,167 tex (37,500 denier) or more, 4,222 tex (38,000 denier) or more, 4,278 tex (38,500 denier) or more, 4,333 tex (39,000 denier) or more, 4,389 tex (39,500 denier) or more, 4,444 tex (40,000 denier) or more, 4,500 tex (40,500 denier) or more, 4,556 tex (41,000 denier) or more, 4,611 tex (41,500 denier) or more, 4,667 tex (42,000 denier) or more, 4,722 tex (42,500 denier) or more, 4,778 tex (43,000 denier) or more, 4,833 tex (43,500 denier) or more, 4,889 tex (44,000 denier) or more, 4,944 tex (44,500 denier) or more, 5,000 tex (45,000 denier) or more, 5,056 tex (45,500 denier) or more, 5,111 tex (46,000 denier) or more, 5,167 tex (46,500 denier) or more, 5,222 tex (47,000 denier) or more, 5,278 tex (47,500 denier) or more, 5,333 tex (48,000 denier) or more, 5,389 tex (48,500 denier) or more, 5,444 tex (49,000 denier) or more, 5,500 tex (49,500 denier) or more, 5,556 tex (50,000 denier) or more, 5,611 tex (50,500 denier) or more, 5,667 tex (51,000 denier) or more, 5,722 tex (51,500 denier) or more, 5,778 tex (52,000 denier) or more, 5,833 tex (52,500 denier) or more, 5,889 tex (53,000 denier) or more, 5,944 tex (53,500 denier) or more, 6,000 tex (54,000 denier) or more, or 6,056 tex (54,500 denier) or more. An upper limit of the total fineness may be, for example, 6,056 tex (54,500 denier) or less, 6,000 tex (54,000 denier) or less, 5,944 tex (53,500 denier) or less, 5,889 tex (53,000 denier) or less, 5,833 tex (52,500 denier) or less, 5,778 tex (52,000 denier) or less, 5,722 tex (51,500 denier) or less, 5,667 tex (51,000 denier) or less, 5,611 tex (50,500 denier) or less, 5,556 tex (50,000 denier) or less, 5,500 tex (49,500 denier) or less, 5,444 tex (49,000 denier) or less, 5,389 tex (48,500 denier) or less, 5,333 tex (48,000 denier) or less, 5,278 tex (47,500 denier) or less, 5,222 tex (47,000 denier) or less, 5,167 tex (46,500 denier) or less, 5,111 tex (46,000 denier) or less, 5,056 tex (45,500 denier) or less, 5,000 tex (45,000 denier) or less, 4,944 tex (44,500 denier) or less, 4,889 tex (44,000 denier) or less, 4,833 tex (43,500 denier) or less, 4,778 tex (43,000 denier) or less, 4,722 tex (42,500 denier) or less, 4,667 tex (42,000 denier) or less, 4,611 tex (41,500 denier) or less, 4,556 tex (41,000 denier) or less, 4,500 tex (40,500 denier) or less, 4,444 tex (40,000 denier) or less, 4,389 tex (39,500 denier) or less, 4,333 tex (39,000 denier) or less, 4,278 tex (38,500 denier) or less, 4,222 tex (38,000 denier) or less, 4,167 tex (37,500 denier) or less, 4,111 tex (37,000 denier) or less, 4,056 tex (36,500 denier) or less, 4,000 tex (36,000 denier) or less, 3,944 tex (35,500 denier) or less, 3,889 tex (35,000 denier) or less, 3,833 tex (34,500 denier) or less, 3,778 tex (34,000 denier) or less, 3,722 tex (33,500 denier) or less, 3,667 tex (33,000 denier) or less, 3,611 tex (32,500 denier) or less, 3,556 tex (32,000 denier) or less, 3,500 tex (31,500 denier) or less, 3,444 tex (31,000 denier) or less, 3,389 tex (30,500 denier) or less, 3,333 tex (30,000 denier) or less, 3,278 tex (29,500 denier) or less, 3,222 tex (29,000 denier) or less, 3,167 tex (28,500 denier) or less, 3,111 tex (28,000 denier) or less, 3,056 tex (27,500 denier) or less, 3,000 tex (27,000 denier) or less, 2,944 tex (26,500 denier) or less, 2,889 tex (26,000 denier) or less, 2,833 tex (25,500 denier) or less, 2,778 tex (25,000 denier) or less, 2,722 tex (24,500 denier) or less, 2,667 tex (24,000 denier) or less, 2,611 tex (23,500 denier) or less, 2,556 tex (23,000 denier) or less, 2,500 tex (22,500 denier) or less, 2,444 tex (22,000 denier) or less, 2,389 tex (21,500 denier) or less, 2,333 tex (21,000 denier) or less, 2,278 tex (20,500 denier) or less, 2,222 tex (20,000 denier) or less, 2,167 tex (19,500 denier) or less, 2,111 tex (19,000 denier) or less, 2,056 tex (18,500 denier) or less, 2,000 tex (18,000 denier) or less, 1,944 tex (17,500 denier) or less, 1,889 tex (17,000 denier) or less, 1,833 tex (16,500 denier) or less, 1,778 tex (16,000 denier) or less, or 1,722 tex (15,500 denier) or less. When the total fineness is out of such a range, the preparation processability of a filter for a smoking article may not be good (continuous process is not possible due to cutting), and when an amount of tow filling filter paper during preparation of a filter for a smoking article may be too small or too large, it may be difficult to secure sufficient filter physical properties (for example, hardness or suction resistance).

[0107] A method of measuring a fineness is not particularly limited, but for example, a lyocell material to be measured, for example, a 2 m sample of lyocell tow, is taken, left, and stabilized in a room with a constant temperature and humidity at a temperature of 20 °C and a humidity of 65 % for 24 hours. One end of the stabilized lyocell tow is fixed, and a 2 kg weight is attached to the other end thereof. The tow stretched due to a load thereof is maintained (stabilized) for 5 seconds and then cut into 90 cm length to obtain a sample and measure a weight of the sample (total fineness). A fineness is converted into a measured weight×10,000 according to a denier conversion method. A single fiber fineness of a monofilament in the sample is calculated by dividing the total fineness of the sample by the number of monofilaments in the sample.

[0108] The total fineness of the lyocell multifilament may be determined according to a single fiber fineness of a filament and the number of crimps. In the present application, a single fiber fineness and the number of crimps may be controlled, and the total fineness of tow suitable for preparing a filter for a smoking article and securing a function thereof may be secured.[Number of crimps]

[0109] In some embodiments, a lyocell multifilament may have 3.94 to 23.62 crimps per centimeter (10 to 60 crimps per inch). The unit "ea / inch (ea / cm)" refers to the number of crimps per unit length (inch or rather cm), wherein the term "ea" refers to the number of crimps. For example, the number of crimps may be 5.91 ea / cm (15 ea / inch) or more, 7.87 ea / cm (20 ea / inch) or more, 9.84 ea / cm (25 ea / inch) or more, 11.81 ea / cm (30 ea / inch) or more, 13.78 ea / cm (35 ea / inch) or more, 15.75 ea / cm (40 ea / inch) or more, or 17.72 ea / cm (45 ea / inch) or more, and an upper limit thereof may be, for example, 21.69 ea / cm (55 ea / inch) or less, 19.69 ea / cm (50 ea / inch) or less, 17.72 ea / cm (45 ea / inch) or less, 15.75 ea / cm (40 ea / inch) or less, 13.78 ea / cm (35 ea / inch) or less, 11.81 ea / cm (30 ea / inch) or less, or 9.84 ea / cm (25 ea / inch) or less. The number of crimps and the uniformity thereof may be controlled under pressure and temperature conditions or the like related to crimping which will be described below.

[0110] Although not particularly limited, the number of crimps may be measured by using, for example, a single fiber property evaluation device (for example, Favimat). Specifically, a sample of a prepared lyocell material (for example, lyocell tow) may be left and stabilized for 24 hours under conditions of a temperature of 20±2 °C and a humidity of 65±4 %. A specimen may be taken from the stabilized sample such that the crimp is not damaged. The taken specimen may be mounted on a dedicated jig with a length (gauge length) of 10 mm to 30 mm. An initial load during measurement may be 0.45 g / tex (0.05 g / denier), and crimp sensitivity may be 0.01 mm. The number of crimps may be measured under the above-described conditions (that is, a temperature of 20±2 °C and a humidity of 65±4 %).

[0111] Although not particularly limited, a lyocell material prepared to satisfy the single fiber fineness, the total fineness, and / or the number of crimps described above may be used in a smoking article.[Binder]

[0112] According to certain embodiments, the lyocell material may further include a binder. The binder may be present, for example, on a surface of the lyocell multifilament or between the lyocell multifilaments (or the monofilaments). The binder may further increase the hardness of a filter for a smoking article, thereby preventing problems such as filter jamming during a process of preparing a filter or a process of preparing a smoking article (for example, a tobacco).

[0113] Types of available binders are not particularly limited, and any known binder may be used at a level that does not impede the purpose of the present disclosure. For example, a binder capable of providing sufficient compatibility with an emulsion used in the present application, improving the hardness of a filter, and providing excellent bonding strength may be used.

[0114] In some embodiments, the binder may include a polyester-based binder, a cellulose-based binder, and / or a vinyl-based binder.

[0115] In some embodiments, as the polyester-based binder, a polyester binder including at least one selected from the group consisting of alkylene, arylene, and heteroarylene having 5 to 12 carbon atoms may be used.

[0116] Examples of the cellulose-based binder may include hydroxypropyl methyl cellulose (HPMC), ethyl cellulose (EC), methyl cellulose (MC), and / or carboxymethyl cellulose (CMC), but one or more embodiments are not limited thereto. According to certain embodiments, the cellulose-based binder is selected from the group consisting of hydroxypropyl methyl cellulose (HPMC), ethyl cellulose (EC), methyl cellulose (MC), carboxymethyl cellulose (CMC), or a combination thereof.

[0117] Examples of the vinyl-based binder may include polyvinylpyrrolidone (PVP), polyvinyl alcohol (PVA), and / or ethylene vinyl acetate (EVAc), but one or more embodiments are not limited thereto. According to certain embodiments, the vinyl-based binder is selected from the group consisting of polyvinylpyrrolidone (PVP), polyvinyl alcohol (PVA), ethylene vinyl acetate (EVAc), or a combination thereof.

[0118] A method of applying the binder onto a lyocell material (coating) will be described below.[Emulsion]

[0119] In some embodiments, the lyocell material may include a lyocell multifilament, and an emulsion applied onto the lyocell multifilament. The emulsion includes: (a) an esterified product of a fatty acid having 16 or more carbon atoms and aliphatic monohydric alcohol; and (b) an esterified product of sorbitan and a fatty acid having 16 or more carbon atoms. The emulsion may be applied onto some or all of monofilaments or multifilaments constituting the lyocell material. In addition, the emulsion may permeate between filaments.

[0120] The emulsion including at least components (a) and (b) may have hydrophobicity. As a result, the lyocell material treated with the emulsion has excellent spreading properties.

[0121] In some embodiments, the lyocell material may include a certain content of the emulsion. In this case, the content of the emulsion may refer to an oil pick up ratio (OPU) (wt%) which will be described below. "OPU" may refer to "oil pick up ratio." In some embodiments, the lyocell material may include the emulsion in a content of 0.1 wt% or more with respect to 100 wt% of the total weight of the lyocell material. For example, the content of the emulsion may be 0.5 wt% or more, 1.0 wt% or more, 1.5 wt% or more, 2.0 wt% or more, 2.5 wt% or more, or 3.0 wt% or more, or specifically 3.5 wt% or more, 4.0 wt% or more, 4.2 wt% or more, 4.5 wt% or more, 5.0 wt% or more, 5.5 wt% or more, 6.0 wt% or more, 6.5 wt% or more, 7.0 wt% or more, 7.5 wt% or more, 8.0 wt% or more, 8.5 wt% or more, 9.0 wt% or more, or 9.5 wt% or more. An upper limit of the content of the emulsion may be, for example, 20.0 wt% or less, 18.0 wt% or less, 17.0 wt% or less, 16.0 wt% or less, 15.0 wt% or less, 14.5 wt% or less, 14.0 wt% or less, 13.5 wt% or less, 13.0 wt% or less, 12.5 wt% or less, 12.0 wt% or less, 11.5 wt% or less, 11.0 wt% or less, 10.5 wt% or less, 10 wt% or less, 9.5 wt% or less, 9.0 wt% or less, 8.5 wt% or less, 8.0 wt% or less, 7.8 wt% or less, or 7.6 wt% or less.

[0122] As a method of measuring the content (OPU) of the emulsion, for example, an extrusion method may be used. For example, a sample (for example, in a content of 2 g to 5 g or specifically about 2.5 g) is collected (in this case, a weight of the collected sample is referred to as a sample weight), and the sample is put into a syringe-shaped container. A material of the container is not particularly limited, but may be a stainless steel (SUS) material. Next, a solvent (for example, methanol) is put into the container into which the sample is put (an amount of the put solvent may be 10 ml or less (for example, about 8 ml)). When the solvent is added to the sample, a dropping method may be used, and a dropping speed may be uniformly adjusted. As described above, the solvent put into the container is allowed to drop on a plate from one end of the syringe-shaped container. In this case, the plate is pre-weighed (a measured weight is referred to as plate weight A), and the plate is installed such that the solvent dropped on the plate is removed away (that is, evaporated) at a temperature of 120 °C to 130 °C (for example, 125 °C). The solvent addition and solvent dropping are performed three times, and pressure (for example, 98 kgf / cm 2< (10 kgf / cm 2< ) or less, 49 N / cm 2< (5 kgf / cm 2< ) or less, or 20 N / cm 2< to 39 N / cm 2< (2 4 kgf / cm 2< to 4 kgf / cm 2< )) is applied to the sample by using a syringe-shaped container to press the sample once. Thus, the solvent and emulsion present in the sample are sufficiently extruded. The sample is squeezed out by applying pressure until the solvent does not come out. Afterwards, the plate is stored in a desiccator for 5 minutes to 10 minutes, and a weight (plate weight B) of the plate containing the sample is measured. Then, a content of the emulsion is calculated according to the following equation.

[0123] In addition, a lyocell material that is used as a reference for the content of the emulsion may be a lyocell multifilament at least treated with an emulsion. For example, the lyocell material may be a lyocell multifilament to which primary emulsion treatment (to be described below) has been applied, a lyocell multifilament to which primary emulsion treatment and secondary emulsion treatment (to be described below) have been applied, or a lyocell multifilament treated with the above-described emulsion and also treated with a binder to be described below. In addition, the lyocell multifilament treated with the emulsion and / or the binder may be imparted with crimps.

[0124] Regarding the emulsion of the present application, component (a) is a compound that may function as a type of lubricant or oil and is a component that may be harmless to the human body enough to be used in food. Component (a) imparts lubricity to fibers put into a crimper. When the lubricity is not sufficient, lyocells clump together and do not escape the crimper, and when the lubricity is too high, there is a problem in that a crimp is not formed properly. In consideration of such functions, a content of component (a) may be controlled as described below.

[0125] Regarding component (a), types of fatty acids having 16 or more carbon atoms forming component (a) are not particularly limited. Fatty acids having 16 or more carbon atoms may be used as long as the fatty acids may provide esterified products that may be harmless to the human body enough to be used in food.

[0126] For example, saturated fatty acids and / or unsaturated fatty acids may be used as fatty acids having one or more 16 carbon atoms.

[0127] Examples of the saturated fatty acids may include a palmitic acid (hexadecanoic acid, CH 3 (CH 2 ) 14 COOH), a margaric acid (heptadecanoic acid, CH 3 (CH 2 ) 15 COOH), a stearic acid (octadecanoic acid, CH 3 (CH 2 ) 16 COOH), a nonadecylic acid (nonadecanoic acid, CH 3 (CH 2 ) 17 COOH), or an arachidic acid (eicosanoic acid, CH 3 (CH 2 ) 18 COOH). However, types of available saturated fatty acids are not limited thereto. According to certain embodiments the saturated fatty acid is selected from the group consisting of palmitic acid (hexadecanoic acid, CH 3 (CH 2 ) 14 COOH), margaric acid (heptadecanoic acid, CH 3 (CH 2 ) 15 COOH), stearic acid (octadecanoic acid, CH 3 (CH 2 ) 16 COOH), nonadecylic acid (nonadecanoic acid, CH 3 (CH 2 ) 17 COOH), arachidic acid (eicosanoic acid, CH 3 (CH 2 ) 18 COOH), or a combination thereof.

[0128] Examples of the unsaturated fatty acids may include a palmitoleic acid (CH 3 (CH 2 ) 5 CH=CH(CH 2 ) 7 COOH), an oleic acid (CH 3 (CH 2 ) 7 CH=CH(CH 2 ) 7 COOH), a linoleic acid (C 18 H 32 O 2 ), or an arachidonic acid (C 20 H 32 O 2 ). According to certain embodiments the unsaturated fatty acid is selected from the group consisting of palmitoleic acid (CH 3 (CH 2 ) 5 CH=CH(CH 2 ) 7 COOH), oleic acid (CH 3 (CH 2 ) 7 CH=CH(CH 2 ) 7 COOH), linoleic acid (C 18 H 32 O 2 ), arachidonic acid (C 20 H 32 O 2 ), or combination thereof.

[0129] However, types of available saturated fatty acids are not limited thereto. According to some embodiments, the fatty acid is selected from the group consisting of a palmitic acid, a margaric acid, a stearic acid, a nonadecylic acid, an arachidic acid, a palmitoleic acid, an oleic acid, a linoleic acid, and an arachidonic acid.

[0130] In some embodiments, an upper limit of a carbon number of the fatty acid having 16 or more carbon atoms is not particularly limited, but may be, for example, 40 or less, 36 or less, 32 or less, 28 or less, 24 or less, or 20 or less.

[0131] Regarding component (a), types of aliphatic monohydric alcohols forming component (a) are also not particularly limited. Aliphatic monohydric alcohols may be used as long as the aliphatic monohydric alcohols may provide esterified products that are harmless to the human body enough to be used in foods.

[0132] In some embodiments, the aliphatic monohydric alcohol may be saturated aliphatic alcohol or unsaturated aliphatic alcohol which may have a linear or branched form.

[0133] In some embodiments, a carbon number of the aliphatic monohydric alcohol may be in a range of 1 to 40. The carbon number of the aliphatic monohydric alcohol may be, for example, 4 or more, 8 or more, 12 or more, 16 or more, or 20 or more.

[0134] Examples of the aliphatic monohydric alcohol may include methanol, ethanol, butanol, lauryl alcohol, isotridecanol, or stearyl alcohol, but one or more embodiments are not limited thereto. According to some embodiments, the aliphatic monohydric alcohol is selected from the group consisting of methanol, ethanol, butanol, lauryl alcohol, isotridecanol, and stearyl alcohol.

[0135] In some embodiments, an esterified product of isotridecanol and a stearic acid (for example, isotridecyl stearate) may be used as component (a). However, types of available component (a) are not limited thereto.

[0136] As will be described below, a content of component (a) included in the emulsion may be adjusted in consideration of the function of the emulsion or the function of component (a).

[0137] Component (b), that is, an esterified product of sorbitan and a fatty acid having 16 or more carbon atoms, may be a compound that may function as a type of emulsifier and may be a component harmless to the human body enough to be used in food.

[0138] Since component (b) has both hydrophilicity and hydrophobicity due to polyhydric alcohol (that is, sorbitan), component (b) enables component (a), which imparts lubricity to fibers, to be well dispersed in water which will be described below. In addition, components (a) and (b) used together not only may increase the dispersibility of the emulsion as described above, but also may lower a melting point, thereby ensuring the use / handling and stability of the emulsion. In consideration of such functions, a content of component (b) may be controlled as described below.

[0139] Regarding component (b), types of fatty acids having 16 or more carbon atoms forming component (b) are not particularly limited. Fatty acids having 16 or more carbon atoms may be used as long as the fatty acids may provide esterified products that may be harmless to the human body enough to be used in food.

[0140] In some embodiments, saturated fatty acids and / or unsaturated fatty acids may be used as fatty acids having one or more 16 carbon atoms.

[0141] Examples of the saturated fatty acids may include a palmitic acid (hexadecanoic acid, CH 3 (CH 2 ) 14 COOH), a margaric acid (heptadecanoic acid, CH 3 (CH 2 ) 15 COOH), a stearic acid (octadecanoic acid, CH 3 (CH 2 ) 16 COOH), a nonadecylic acid (nonadecanoic acid, CH 3 (CH 2 ) 17 COOH), or an arachidic acid (eicosanoic acid, CH 3 (CH 2 ) 18 COOH). According to certain embodiments, the saturated fatty acid is selected from the group consisting of palmitic acid (hexadecanoic acid, CH 3 (CH 2 ) 14 COOH), margaric acid (heptadecanoic acid, CH 3 (CH 2 ) 15 COOH), stearic acid (octadecanoic acid, CH 3 (CH 2 ) 16 COOH), nonadecylic acid (nonadecanoic acid, CH 3 (CH 2 ) 17 COOH), arachidic acid (eicosanoic acid, CH 3 (CH 2 ) 18 COOH), or a combination thereof. However, types of available saturated fatty acids are not limited thereto.

[0142] Examples of the unsaturated fatty acids may include a palmitoleic acid (CH 3 (CH 2 ) 5 CH=CH(CH 2 ) 7 COOH), an oleic acid (CH 3 (CH 2 ) 7 CH=CH(CH 2 ) 7 COOH), a linoleic acid (C 18 H 32 O 2 ), or an arachidonic acid (C 20 H 32 O 2 ). In certain embodiments, the unsaturated fatty acid is selected from the group consisting of palmitoleic acid (CH 3 (CH 2 ) 5 CH=CH(CH 2 ) 7 COOH), oleic acid (CH 3 (CH 2 ) 7 CH=CH(CH 2 ) 7 COOH), linoleic acid (C 18 H 32 O 2 ), arachidonic acid (C 20 H 32 O 2 ), or a combination thereof. However, types of available saturated fatty acids are not limited thereto. According to some embodiments, the fatty acid is selected from the group consisting of a palmitic acid, a margaric acid, a stearic acid, a nonadecylic acid, an arachidic acid, a palmitoleic acid, an oleic acid, a linoleic acid, and an arachidonic acid.

[0143] An upper limit of a carbon number of the fatty acid having 16 or more carbon atoms is not particularly limited, but may be, for example, 40 or less, 36 or less, 32 or less, 28 or less, 24 or less, or 20 or less.

[0144] In some embodiments, an esterified product of sorbitan and an oleic acid (for example, sorbitan monooleate) may be used as component (b). However, types of available component (b) are not limited thereto.

[0145] A content of component (b) may be adjusted in consideration of the function of component (b) and the function of the emulsion as described above.

[0146] In some embodiments, the emulsion may include (b) the esterified product of sorbitan and a fatty acid having 16 or more carbon atoms in a content of 20 parts by weight to 60 parts by weight with respect to 100 parts by weight of (a) the esterified product of a fatty acid having 16 or more carbon atoms and aliphatic monohydric alcohol.

[0147] For example, the emulsion of the present application may include component (b) in a content of 25 parts by weight or more, 30 parts by weight or more, 35 parts by weight or more, 40 parts by weight or more, 45 parts by weight or more, or 50 parts by weight or more with respect to 100 parts by weight of component (a). An upper limit of the content of component (b) with respect to 100 parts by weight of component (a) may be, for example, 55 parts by weight or less, 50 parts by weight or less, 45 parts by weight or less, 40 parts by weight or less, 35 parts by weight or less, 30 parts by weight or less, or 25 parts by weight or less. When such a range of the content is satisfied, a surface of a lyocell multifilament or lyocell tow treated with an emulsion may have hydrophobicity.

[0148] In some embodiments, the emulsion may include (a) the esterified product of a fatty acid having 16 or more carbon atoms and aliphatic monohydric alcohol in a content of 40 wt% to 80 wt% with respect to 100 wt% of the total weight of the emulsion. For example, the content of component (a) may be 45 wt% or more, 50 wt% or more, 55 wt% or more, 60 wt% or more, or 65 wt% or more, 70 wt% or more, or 75 wt% or more with respect to 100 wt% of the total weight of the emulsion. An upper limit of the content of component (a) may be, for example, 75 wt% or less, 70 wt% or less, 65 wt% or less, 60 wt% or less, 55 wt% or less, 50 wt% or less, or 45 wt% or less.

[0149] In some embodiments, the emulsion may include an excess amount of component (a).

[0150] In some embodiments, the emulsion may include (b) the esterified product of sorbitan and a fatty acid having 16 or more carbon atoms in a content of 15 wt% to 55 wt% with respect to 100 wt% of the total weight of the emulsion. Specifically, the content of component (b) may be 20 wt% or more, 25 wt% or more, 30 wt% or more, 35 wt% or more, 40 wt% or more, 45 wt% or more, or 50 wt% or more with respect to 100 wt% of the total weight of the emulsion. An upper limit of the content of component (b) may be, for example, 50 wt% or less, 45 wt% or less, 40 wt% or less, 35 wt% or less, 30 wt% or less, or 25 wt% or less.

[0151] In some embodiments, the emulsion may further include water. A small amount of water may assist in emulsifying.

[0152] A content of water is not particularly limited, but water may be included in the remaining content excluding the total content of components (a) and (b) with respect to 100 wt% of the total weight of the emulsion. The content of water in the emulsion (that is, the remaining content excluding the total content of the remaining components excluding water) may be, for example, 10 wt% or less, 9 wt% or less, 8 wt% or less, 7 wt% or less, 6 wt% or less, 5 wt% or less, 4 wt% or less, 3 wt% or less, 2 wt% or less, or 1 wt% or less. A lower limit of the content of water may be, for example, 0 wt% or more, 0.1 wt% or more, 0.5 wt% or more, or 1 wt% or more.[Method of preparing lyocell material]

[0153] The present application relates to a method of preparing a lyocell material. Through the method, a lyocell material may be prepared and used in a smoking article.

[0154] In some embodiments, the method of preparing a lyocell material includes: lyocell dope spinning; coagulating, and obtaining multifilament; washing; emulsion treatment; and crimp imparting (crimping or rather crimping step). In addition, the method of preparing a lyocell material may further include: binder treatment; and other steps.

[0155] The emulsion treatment may be performed before the crimp imparting, after the crimp imparting, or before and after the crimp imparting.

[0156] Each emulsion treatment may independently be performed, for example, by spraying an emulsion with the above-described composition onto a lyocell multifilament or immersing the lyocell multifilament in the emulsion. The emulsion treatment may be performed such that a content (for example, OPU (wt%)) of an emulsion in the lyocell material satisfies a certain range, as described above.

[0157] The crimp imparting may be performed, for example, by applying steam and / or pressure to the lyocell multifilament.

[0158] The method of preparing a lyocell material according to a specific embodiment of the present application, including the emulsion treatment and the crimp imparting, will be described in more detail below. The method of the present application may be performed by including one or more of operations described below.<Lyocell dope spinning (a)>

[0159] A corresponding step is a step of spinning a lyocell spinning dope including lyocell cellulose (or cellulose pulp) and N-methylmorpholine-N-oxide (NMMO).

[0160] Commercialized cellulose acetate filters are pointed out as the major cause of microplastics. However, since an amine oxide-based solvent used in preparing lyocell fibers is recyclable and biodegradable even when discarded, lyocell materials do not generate any pollutants during a production process thereof. Furthermore, since lyocell tow is biodegraded and removed within a relatively short period of time, lyocell is a more environmentally friendly material than cellulose acetate.

[0161] In some embodiments, a content of cellulose in the spinning dope may be in a range of 5 wt% to 15 wt% with respect to 100 wt% of the total weight of the dope. When the content of cellulose is too low, it is difficult to implement the properties of lyocell fiber, and when the content exceeds such a range, it is difficult to dissolve cellulose in a solvent. In consideration of the difficulties, the content of cellulose in the spinning dope may be, for example, 6 wt% or more, 7 wt% or more, 8 wt% or more, 9 wt% or more, or 10 wt% or more, and an upper limit thereof may be, for example, 14 wt% or less, 13 wt% or less, 12 wt% or less, 11 wt% or less, 10 wt% or less, or 9 wt% or less. The term "cellulose" may refer to "lyocell cellulose."

[0162] In some embodiments, the spinning dope may include an aqueous solution of NMMO. The aqueous solution may include, for example, NMMO in a content of 80 parts by weight to 95 parts by weight and water in a content of 5 parts by weight to 20 parts by weight in consideration of a degree of dissolution of cellulose and a process temperature.

[0163] In some embodiments, the cellulose or cellulose pulp may include alpha-cellulose in a content of 85 wt% to 97 wt% with respect to 100 wt% of the total weight of the cellulose.

[0164] In some embodiments, the cellulose or cellulose pulp may include hemicellulose in a content of 1 wt% to 15 wt% with respect to 100 wt% of the total weight of the cellulose. By adjusting the content of the hemicellulose within such a range, the stable physical properties (for example, hardness or suction resistance implementation) and processability of a lyocell material may be more easily secured.

[0165] In some embodiments, in a specific example of the present application, a degree of polymerization (DPw) of the cellulose may be in a range of 600 to 1,700. The polymerization degree may refer to the number of repeating units and / or monomeric units of the components (cellulose, hemicellulose, etc.) contained in the cellulose pulp. In particular, as used in this application, the term "polymerization degree" may refer to the number of monomeric units and / or repeating units in a macromolecule or polymer or oligomer molecule. The polymerization degree (DPw) may be given by DPw = Mn / M0 wherein Mn is the number-average molecular weight of the macromolecule or polymer or oligomer molecule and M0 is the molecular weight of the monomeric unit.

[0166] In the spinning, a shape of a spinneret for discharging the spinning dope is not particularly limited. For example, a donut-shaped spinneret may be used.

[0167] A nozzle temperature of the spinneret, specifically, a spinning temperature thereof, may be appropriately selected by a person skilled in the art. Considering that the viscosity of the spinning dope may vary according to the spinning temperature, and thus discharging may not be performed smoothly, the spinning temperature may be, for example, in a range of 100 °C to 120 °C or 100 °C to 110 °C.

[0168] In some embodiments, the spinning of the spinning dope may be performed under spinning conditions in which a single fiber fineness of a filament is controlled to be in a range of 1.67 dtex to 8.894 dtex (1.5 denier to 8.0 denier). For example, one or more spinning conditions of a discharge amount and a spinning speed of the spinning dope may be appropriately controlled so that a single fiber fineness of a filament included in a lyocell material may satisfy a range of 1.67 dtex to 8.89 dtex (1.5 denier to 8.0 denier). In this case, a single fiber fineness of a filament refers to a fineness of a single monofilament separated from a multifilament, as described above.

[0169] An upper limit of the single fiber fineness of the filament may be, for example, 8.33 dtex (7.5 denier) or less, 7.78 dtex (7.0 denier) or less, 7.22 dtex (6.5 denier) or less, 6.67 dtex (6.0 denier) or less, 6.11 dtex (5.5 denier) or less, 5.56 dtex (5.0 denier) or less, 5.00 dtex (4.5 denier) or less, 3.89 dtex (3.5 denier) or less, 3.33 dtex (3.0 denier) or less, or 2.78 dtex (2.5 denier) or less. A lower limit of the single fiber fineness may be, for example, 2.22 dtex (2.0 denier) or more, 2.78 dtex (2.5 denier) or more, 3.33 dtex (3.0 denier) or more, 3.89 dtex (3.5 denier) or more, 4.44 dtex (4.0 denier) or more, 5.00 dtex (4.5 denier) or more, 5.56 dtex (5.0 denier) or more, 6.11 dtex (5.5 denier) or more, 6.67 dtex (6.0 denier) or more, 7.22 dtex (6.5 denier) or more, or 7.78 dtex (7.0 denier) or more. Satisfying such a range may be more advantageous in implementing the stable suction resistance of a filter for a smoking article. and securing the processability thereof.

[0170] The spinning dope discharged through the spinneret may undergo coagulation which will be described below.<Coagulating, and obtaining multifilament(b)>

[0171] In a corresponding step, the spun spinning dope may be coagulated, and a lyocell multifilament may be obtained.

[0172] For the coagulation, a method in which the spinning dope comes into contact with air and / or a coagulating solution may be used.

[0173] For example, the coagulation may include: primary coagulation of supplying cooling air to a spun lyocell dope; and secondary coagulation of adding a primarily coagulated spinning dope to a coagulating solution to coagulate the spinning dop.

[0174] According to such a coagulation, the lyocell dope discharged from the spinneret may be primarily coagulated in a space (air gap section) between the spinneret and a coagulation tank. For example, cooling air may be supplied to the air gap section from an air cooling part positioned inside the spinneret in a direction from the inside to the outside of the spinneret. In addition, the primary coagulation may be performed through a known so-called air quenching method or means in the related field.

[0175] For example, an upper limit of a temperature of the cooling air used for the primary coagulation may be, for example, 15 °C or less. For example, the cooling air may be air with a temperature of 14 °C or less, 13 °C or less, 12 °C or less, 11 °C or less, or 10 °C or less. When the above temperature is exceeded, the coagulation of the spinning dope by air is not sufficient, and spinning-related processability is not good.

[0176] A lower limit of the temperature of the cooling air may be determined in consideration of spinning processability and / or cross-sectional uniformity of a filament. For example, when the temperature of the cooling air is less than 4 °C, a surface of the spinneret cools, a surface of the filament becomes non-uniform, and spinning processability also deteriorates. In consideration of this, the cooling air may have, for example a temperature of 5 °C or more, 6 °C or more, 7 °C or more, 8 °C or more, or 9 °C or more.

[0177] A degree by which the cooling air is supplied may be adjusted in consideration of sufficient coagulation, spinning processability, and an influence on the physical properties of the filament. For example, the cooling air may be supplied to the discharged spinning dope at an air flow rate of 70 Nm 3< / h to 400 Nm 3< / h. For example, the air flow rate may be 100 Nm 3< / h or more, 150 Nm 3< / h or more, 200 Nm 3< / h or more, or 250 Nm 3< / h or more, and an upper limit thereof may be, for example, 350 Nm 3< / h or less, 300 Nm 3< / h or less, 250 Nm 3< / h or less, 200 Nm 3< / h or less, or 150 Nm 3< / h or less.

[0178] After the primary coagulation as described above, the cooled spinning dope may be supplied to a coagulation tank or bath containing a coagulating solution (secondary coagulation). For proper coagulation, a temperature of the coagulating solution may be, for example, 30 °C or less or 25 °C or less. The temperature of the coagulating solution may be, for example, 10 °C or more, 15 °C or more, or 20 °C or more. When the above temperature is maintained, a coagulation speed may be appropriately maintained.

[0179] A type of a coagulating solution for the secondary coagulation as described above is not particularly limited. For example, the coagulating solution may include at least one selected from water and NMMO.

[0180] Although not particularly limited, when the coagulating solution includes water and NMMO, with respect to 100 wt% of the total weight of the coagulating solution, a content of water in the coagulating solution may be in a range of 60 wt% to 90 wt%, and a content of NMMO may be in a range of 10 wt% to 40 wt%. Alternatively, the coagulating solution may include water in a content of about 70 wt% to about 80 wt% and NMMO in a content of about 20 wt% to about 30 wt% with respect to 100 wt% of the total weight of the coagulating solution. By using sensors or the like, a concentration of the coagulating solution may be controlled to be maintained during a preparation process.<Washing C>

[0181] If necessary, washing may be performed on a lyocell multifilament after the above-described coagulation and multifilament obtainment. Through such washing, NMMO and / or other impurities remaining in the filament may be removed.

[0182] A method of performing washing is not particularly limited. For example, washing may be performed by introducing a coagulated lyocell multifilament into a washing tank by using a traction roller. Alternatively, washing may be performed by spraying a washing solution while moving to a subsequent operation by a traction roller.

[0183] Components of the washing solution are not particularly limited. For example, the washing solution may include water and may further include known other additives.

[0184] In addition, in consideration of reuse after washing, the washing solution may be used by adjusting a temperature thereof to 100 °C or less.<Emulsion treatment (d)>

[0185] If required, a step of treating the lyocell multifilament with an emulsion may be performed. The step is a step of applying an emulsion with the above-described components onto a surface of the filament. Through emulsion treatment, friction applied to the filament may be reduced, and crimps may be formed well in the crimp imparting which will be described below. When the emulsion treatment is performed twice or more as described below, the emulsion treatment may be referred to as primary emulsion treatment and secondary emulsion treatment according to the order.

[0186] Although not particularly limited, the emulsion treatment may be performed by immersing the lyocell multifilament in a bath filled with an emulsion such that the lyocell multifilament is completely immersed in the emulsion. Alternatively, the emulsion treatment may be performed by spraying the emulsion while moving to a subsequent operation by a traction roller.

[0187] In order to ensure that an amount of the emulsion applied onto the lyocell multifilament is constant after the emulsion treatment as described above, a process in which rolls or the like positioned before and / or after the emulsion treatment squeeze out an emulsion of a surface of the lyocell multifilament may be additionally performed.

[0188] In some embodiments, the emulsion treatment may be performed such that a content (OPU (wt%)) of the emulsion is 1.0 wt% or more with respect to 100 wt% of a lyocell multifilament which has been at least treated with an emulsion. In this case, the lyocell multifilament which has been at least treated with the emulsion, for example, the lyocell material, may be a lyocell multifilament to which primary emulsion treatment has been applied, a lyocell multifilament to which primary emulsion treatment and secondary emulsion treatment (see the description below) have been applied, or a lyocell multifilament to which the emulsion treatment as described above and a binder described below have been applied together. The lyocell multifilament treated with the emulsion and / or the binder as described above may be imparted with crimps.

[0189] For example, in the lyocell multifilament which has been at least treated with the emulsion, a content of the emulsion may be 0.5 wt% or more, 1.0 wt% or more, 1.5 wt% or more, 2.0 wt% or more, 2.5 wt% or more, or 3.0 wt% or more, specifically 3.5 wt% or more, 4.0 wt% or more, 4.2 wt% or more, 4.5 wt% or more, 5.0 wt% or more, 5.5 wt% or more, 6.0 wt% or more, 6.5 wt% or more, 7.0 wt% or more, 7.5 wt% or more, 8.0 wt% or more, 8.5 wt% or more, 9.0 wt% or more, or 9.5 wt% or more with respect to 100 wt% of the total weight of the lyocell multifilament which has been at least treated with the emulsion. An upper limit of the content of the emulsion may be, for example, 20.0 wt% or less, 18.0 wt% or less, 17.0 wt% or less, 16.0 wt% or less, 15.0 wt% or less, 14.5 wt% or less, 14.0 wt% or less, 13.5 wt% or less, 13.0 wt% or less, 12.5 wt% or less, 12.0 wt% or less, 11.5 wt% or less, 11.0 wt% or less, 10.5 wt% or less, 10 wt% or less, 9.5 wt% or less, 9.0 wt% or less, 8.5 wt% or less, 8.0 wt% or less, 7.8 wt%, or 7.6 wt% or less with respect to 100 wt% of the total weight of the lyocell multifilament which has been at least treated with the emulsion. In this case, the above content may refer to a dry weight after a solvent (for example, water) or liquid component that may be included in the emulsion has evaporated.

[0190] When the lyocell multifilament is treated with the emulsion with the above-described composition within such a range of the content, the hydrophilic properties of the lyocell material may be supplemented.

[0191] In some embodiments, the emulsion may be dried after the emulsion treatment as described above.

[0192] In some embodiments, one or more of the above-described operations may be controlled such that a single fiber fineness of a filament constituting the lyocell multifilament may be in a range of 1.67 to 8.89 dtex (1.5 denier to 8.0 denier). The single fiber fineness of the filament refers to a fineness of a single monofilament separated from a multifilament, as described above.

[0193] In some embodiments, one or more of the above-described operations may be controlled such that the single fiber fineness of the filament constituting the lyocell multifilament may be in a range of 1.67 dtex to 8.89 dtex (1.5 denier to 8.0 denier). The single fiber fineness of the filament refers to a fineness of a single monofilament separated from a multifilament, as described above.

[0194] An upper limit of the single fiber fineness of the filament may be, for example, 8.33 dtex (7.5 denier) or less, 7.78 dtex (7.0 denier) or less, 7.22 dtex (6.5 denier) or less, 6.67 dtex (6.0 denier) or less, 6.11 dtex (5.5 denier) or less, 5.56 dtex (5.0 denier) or less, 5.00 dtex (4.5 denier) or less, 3.89 dtex (3.5 denier) or less, 3.33 dtex (3.0 denier) or less, or 2.78 dtex (2.5 denier) or less. A lower limit of the single fiber fineness may be 2.22 dtex (2.0 denier) or more, 2.78 dtex (2.5 denier) or more, 3.33 dtex (3.0 denier) or more, 3.89 dtex (3.5 denier) or more, 4.44 dtex (4.0 denier) or more, 5.00 dtex (4.5 denier) or more, 5.56 dtex (5.0 denier) or more, 6.11 dtex (5.5 denier) or more, 6.67 dtex (6.0 denier) or more, 7.22 dtex (6.5 denier) or more, or 7.78 dtex (7.0 denier) or more. Satisfying such a range may be more advantageous in implementing the stable suction resistance of a filter for a smoking article and securing the processability thereof.

[0195] Although not particularly limited, a step controlled to secure such a range of the single fiber fineness may be the above-described spinning. Alternatively, the above-described spinning, coagulation, washing, and emulsion treatment may all be controlled to secure such a range of the single fiber fineness.<Crimp imparting (e)>

[0196] The crimp imparting is a step of applying pressure to the lyocell multifilament treated with the emulsion through steam and / or a press roller to obtain a crimped multifilament, for example, crimped tow. The crimp imparting may be referred to as crimping.

[0197] Through crimping, waves may be imparted to the lyocell multifilament, and fibers may have bulky properties. According to certain embodiments, the crimping may be performed by using a known crimp machine including a stuffer box and / or a steam box, and available crimp machines are not particularly limited as long as the crimp machines are devices capable of applying one or more of pressures which will be described below.

[0198] In some embodiments, a moisture content of the lyocell material measured before the crimp imparting may be in a range of 150 % to 400 %.

[0199] For example, the crimp imparting may be performed by first supplying steam to the lyocell multifilament to preheat and swell the lyocell multifilament, and then pressing the lyocell multifilament with a press roller to form wrinkles in the lyocell multifilament. In this case, the steam box may be used to supply steam and may be positioned in front of the crimp machine.

[0200] For example, the crimp imparting may be performed in such a manner that pressing of the lyocell multifilament by the press roller and applying of steam are simultaneously performed.

[0201] For example, the crimp imparting may be performed in such a manner that steam is first supplied to the lyocell multifilament to preheat and swell the lyocell multifilament, and then pressing of the lyocell multifilament by the press roller and applying of steam are simultaneously performed.

[0202] For example, the crimp imparting may be performed by applying steam with a pressure of about 0.98 N / cm 2< to about 19.61 N / cm 2< (about 0.1 kgf / cm 2< to 2.0 kgf / cm 2< ) to each lyocell multifilament before the lyocell multifilament is input into the crimp machine (specifically, the press roller).

[0203] For example, steam with a pressure of 1.96 N / cm 2< (0.2 kgf / cm 2< ) or more, 2.94 N / cm 2< (0.3 kgf / cm 2< ) or more, 3.92 N / cm 2< (0.4 kgf / cm 2< ) or more, 4.90 N / cm 2< (0.5 kgf / cm 2< ) or more, or 5.88 N / cm 2< (0.6 kgf / cm 2< ) or more may be supplied by the steam box. In addition, steam with a pressure of 14.71 N / cm2 (1.5 kgf / cm2) or less, 13.73 N / cm2 (1.4 kgf / cm2) or less, 12.75 N / cm2 (1.3 kgf / cm2) or less, 11.77 N / cm2 (1.2 kgf / cm2) or less, 10.79 N / cm2 (1.1 kgf / cm2) or less, or 9.81 N / cm2 (1.0 kgf / cm2) or less may be supplied. When an amount or pressure of supplied steam is less than such a range, crimps may not be formed smoothly. When such a range is exceeded, since the flexibility of a filament is increased, excessive crimps may be imparted to the filament in the crimp machine, and thus the filament may not pass through the crimp machine.

[0204] For example, the crimp imparting may be performed by pressing the lyocell multifilament with the press roller to form wrinkles in the lyocell multifilament. In addition, steam may not be supplied before pressing, steam may not be supplied simultaneously with pressing, or steam may not be supplied before pressing and simultaneously with pressing.

[0205] For example, the crimp imparting may be performed by each independently applying pressures of 14.71 N / cm 2< to 39.23 N / cm 2< (1.5 kgf / cm 2< to 4.0 kgf / cm 2< ) to each lyocell multifilament put into the crimp machine by using the press roller.

[0206] For example, a pressure of 15.69 N / cm 2< (1.6 kgf / cm 2< ) or more, 16.67 N / cm 2< (1.7 kgf / cm 2< ) or more, 17.65 N / cm 2< (1.8 kgf / cm 2< ) or more, 18.63 N / cm 2< (1.9 kgf / cm 2< ) or more, 19.61 N / cm 2< (2.0 kgf / cm 2< ) or more, 20.60 N / cm 2< (2.1 kgf / cm 2< ) or more, 21.58 N / cm 2< (2.2 kgf / cm 2< ) or more, 22.56 N / cm 2< (2.3 kgf / cm 2< ) or more, 23.54 N / cm 2< (2.4 kgf / cm 2< ) or more, or 24.52 N / cm 2< (2.5 kgf / cm 2< ) or more may be applied to the lyocell multifilament through the press roller. In addition, a pressure of 38.25 N / cm 2< (3.9 kgf / cm 2< ) or less, 37.27 N / cm 2< (3.8 kgf / cm 2< ) or less, 36.29 N / cm 2< (3.7 kgf / cm 2< ) or less, 35.31 N / cm 2< (3.6 kgf / cm 2< ) or less, 34.33 N / cm 2< (3.5 kgf / cm 2< ) or less, 33.35 N / cm 2< (3.4 kgf / cm 2< ) or less, 32.37 N / cm 2< (3.3 kgf / cm 2< ) or less, 31.39 N / cm 2< (3.2 kgf / cm 2< ) or less, 30.41 N / cm 2< (3.1 kgf / cm 2< ) or less, 29.42 N / cm 2< (3.0 kgf / cm 2< ) or less, 28.44 N / cm 2< (2.9 kgf / cm 2< ) or less, 27.46 N / cm 2< (2.8 kgf / cm 2< ) or less, 26.48 N / cm 2< (2.7 kgf / cm 2< ) or less, 25.50 N / cm 2< (2.6 kgf / cm 2< ) or less, or 24.52 N / cm 2< (2.5 kgf / cm 2< ) or less may be applied through the press roller.

[0207] When the pressure of the press roller is less than such a range, the desired number of crimps may not be formed sufficiently. When roller pressure exceeds such a range, a pressing force may be too strong, and thus the filament may not be smoothly put into the crimp machine or may not pass through the stuffer box. Wrinkles may be formed in the lyocell multifilament by the press roller that provides the pressure.

[0208] For example, by using an upper plate, pressures of 0.98 N / cm 2< to 19.61 N / cm 2< (0.1 kgf / cm 2< to 2 kgf / cm 2< ) may each independently be applied to each lyocell multifilament. In addition, the upper plate may apply pressure to each lyocell multifilament when each lyocell multifilament has passed through the press roller or while each lyocell multifilament is passing through the press roller.

[0209] For example, the pressure applied by the upper plate may be 1.96 N / cm 2< (0.2 kgf / cm 2< ) or more, 2.94 N / cm 2< (0.3 kgf / cm 2< ) or more, 3.92 N / cm 2< (0.4 kgf / cm 2< ) or more, or 4.90 N / cm 2< (0.5 kgf / cm 2< ) or more. In addition, a pressure of 14.71 N / cm 2< (1.5 kgf / cm 2< ) or less, 13.73 N / cm 2< (1.4 kgf / cm 2< ) or less, 12.75 N / cm 2< (1.3 kgf / cm 2< ) or less, 11.77 N / cm 2< (1.2 kgf / cm 2< ) or less, 10.79 N / cm 2< (1.1 kgf / cm 2< ) or less, or 9.81 N / cm 2< (1.0 kgf / cm 2< ) or less may be applied by the upper plate.

[0210] Furthermore, when the pressure of the upper plate, which vertically moves to provide uniform crimps after each lyocell multifilament passes through the press roller, is less than 0.98 N / cm 2< (0.1 kgf / cm 2< ), since the upper plate may not be fixed due to a pressure inside the stuffer box, while tow remains inside the stuffer box for a long time, the continuity of a process may not be maintained. When the pressure of the upper plate exceeds 19.61 N / cm 2 (< 2 kgf / cm 2< ), since steam inside the stuffer box may not be smoothly discharged, a shape of a crimp may be irregular.

[0211] For example, in the crimp imparting, a doctor blade that applies certain pressure to the lyocell multifilament may be applied. The doctor blade may adjust a residence time of a filament put into a crimper stuffer box, thereby contributing to the adjustment of the number of crimps. The doctor blade may be positioned, for example, on a movement path of the lyocell multifilament that is pressed by the above-described press roller and then discharged from a roller pressing point.

[0212] For example, the crimp imparting may be performed by each independently applying pressures of 0.98 N / cm 2< to 19.61 N / cm 2< (0.1 kgf / cm 2< to 2.0 kgf / cm 2< ) to each lyocell multifilament, which has passed a roller of the crimp machine, by using the doctor blade.

[0213] For example, the pressure applied by the doctor blade may be 1.96 N / cm 2< (0.2 kgf / cm 2< ) or more, 2.94 N / cm 2< (0.3 kgf / cm 2< ) or more, 3.92 N / cm 2< (0.4 kgf / cm 2< ) or more, or 4.90 N / cm 2< (0.5 kgf / cm 2< ) or more. In addition, a pressure of 14.71 N / cm 2< (1.5 kgf / cm 2< ) or less, 13.73 N / cm 2< (1.4 kgf / cm 2< ) or less, 12.75 N / cm 2< (1.3 kgf / cm 2< ) or less, 11.77 N / cm 2< (1.2 kgf / cm 2< ) or less, 10.79 N / cm 2< (1.1 kgf / cm 2< ) or less, or 9.81 N / cm 2< (1.0 kgf / cm 2< ) or less may be applied by the doctor blade.

[0214] For example, the crimp imparting may be performed at a temperature ranging from 120 °C to 250 °C. When the temperature is too low, the effect of stabilizing a shape of crimps may not be good, and when the temperature is too high, a concentration of fat and oil inside the stuffer box may be increased, which may make it difficult to form crimps. Therefore, in consideration of the above-described pressure of the steam or the like, a temperature, for example, may be appropriately controlled in a range of 130 °C or more, 140 °C or more, or 150°C or more, and 200 °C or less, 180 °C or less, or 160 °C or less.<Binder treatment (f)>

[0215] In an example, the method may further include a step of treating, with a binder, the lyocell multifilament treated with the emulsion, or treating, with a binder, the lyocell multifilament obtained through the crimp imparting.

[0216] When a filter for a smoking article is prepared by using the lyocell material (for example, lyocell tow), a binder may be additionally used. The binder may increase the hardness of a filter for a smoking article including a lyocell material, thereby preventing problems such as filter jamming during a process of preparing a filter or a process of preparing a tobacco.

[0217] The treatment of the lyocell material with the binder is not particularly limited. For example, binder treatment may be performed by immersing the lyocell multifilament in a bath filled with a binder (or a binder solution) such that the lyocell multifilament is completely immersed in the binder. Alternatively, binder coating may be performed by spraying (or injecting) the binder (or the binder solution) through a nozzle.

[0218] Types and components of available binders are as described above, and thus descriptions thereof are omitted.

[0219] For example, the binder (or the binder solution) may further include a solvent in addition to the components described above. Examples of the solvent may include water, ethanol, propylene glycol, and / or glycerin, but one or more embodiments are not limited thereto. In some embodiments, the solvent is selected from the group consisting of water, ethanol, propylene glycol, glycerin, or a combination thereof. When the binder (or the binder solution) includes a solvent, a content of the solvent may be, for example, in a range of about 20 to about 80 wt% or about 40 wt% to about 60 wt% with respect to 100 wt% of the total weight of the binder (or the binder solution).

[0220] Such binder treatment may be performed at a level that may achieve the purpose of the above-described binder treatment. For example, the binder treatment may be performed such that a content of the binder satisfies 20 wt% or less, for example, a range of 8 wt% to 15 wt%, with respect to 100 wt% of a lyocell multifilament treated with an emulsion and a binder. In this case, the above content may refer to a dry weight after a solvent or liquid component that may be included in the binder has evaporated.

[0221] After the binder is applied onto the lyocell multifilament, drying of the binder may be performed. A drying temperature is not particularly limited, but, for example, drying may be performed at room temperature (about 10 °C to about 35 °C).<Stacking and pressing (g)>

[0222] After the crimp imparting, an operation of stacking and pressing the lyocell material may be further performed. Through the stacking and pressing, the lyocell material may be stacked and pressed in a certain container. For example, the container may be a hexahedral box and may be filled with the lyocell material through the stacking and pressing.

[0223] In addition, an FPI measured from the lyocell material after the stacking and pressing may be in a range of 19 to 88. Preferably, the FPI measured from the lyocell material after the stacking and pressing may be in a range of 24 to 75.

[0224] In addition, in order for the FPI to satisfy a range of 19 to 88, the stacking and pressing may be performed such that density A (that is, an apparent density) in Equation 2 is in a range of 0.300 g / cm 3< to 1.200 g / cm 3< .

[0225] In some embodiments, more specifically, an upper limit of density A implemented in the stacking and pressing may be 1.150 g / cm 3< or less, 1.100 g / cm 3< or less, 1.050 g / cm 3< or less, 1.000 g / cm 3< or less, 0.950 g / cm 3< or less, 0.900 g / cm 3< or less, 0.850 g / cm 3< or less, 0.800 g / cm 3< or less, 0.750 g / cm 3< or less, 0.700 g / cm 3< or less, or 0.650 g / cm 3< or less. In addition, a lower limit of density A implemented in the stacking and pressing may be, for example, 0.350 g / cm 3< or more, 0.400 g / cm 3< or more, 0.450 g / cm 3< or more, 0.500 g / cm 3< or more, 0.550 g / cm 3< or more, 0.600 g / cm 3< or more, 0.650 g / cm 3< or more, 0.700 g / cm 3< or more, 0.750 g / cm 3< or more, 0.800 g / cm 3< or more, or 0.850 g / cm 3< or more. Preferably, density A implemented in the stacking and pressing may be in a range of 0.500 g / cm 3< to 0.900 g / cm 3< .

[0226] In some embodiments, a pressing pressure of the stacking and pressing may be in a range of 196 N / cm 2< to 588 N / cm 2< (20 kgf / cm 2< to 60 kgf / cm 2< ). When the pressing pressure satisfies such a numerical range, the post-processing properties of the lyocell material such as unwinding properties may be improved.

[0227] When the pressing pressure is less than 196 N / cm 2< (20 kgf / cm 2< ), density A may be excessively low, and Po may exceed 80. As a result, the clumping of the lyocell material may be a problem. When the pressing pressure exceeds 588 N / cm 2< (60 kgf / cm 2< ), density A may be excessively high, and Po may be less than 20. As a result, the cutting of lyocell material may be a problem.

[0228] In addition, the stacking and pressing may be performed such that Po in Equation 1 may be in a range of 15 % to 83 %. For example, Po may be adjusted by performing the stacking and pressing such that density A is in a range of 0.300 g / cm 3< and 1.200 g / cm 3< .<Other steps (h)>

[0229] After the crimp imparting, appropriate post-treatment may be additionally performed.

[0230] In an example, secondary emulsion treatment (h1) may be additionally performed. Through the secondary emulsion treatment, flexibility may be further imparted to tow. The secondary emulsion treatment may be performed in the same manner as or in accordance with the emulsion treatment (d) described above.

[0231] Specifically, the secondary emulsion treatment may be performed by treating, with an emulsion, a lyocell material which has undergone a process using a crimper. The secondary emulsion treatment may function advantageously in various processes performed during the preparation of a filter for a smoking article. For example, the secondary emulsion treatment may allow fibers and filters to spread well even in air during a spreading process and also may restrict fibers from being cut during a stretching process.

[0232] In some embodiments, the secondary emulsion treatment as described above may be performed before or after the binder treatment. Alternatively, the secondary emulsion treatment may be performed irrespective of whether the binder treatment is performed.

[0233] Even in a case in which the secondary emulsion treatment as described above is performed, a secondary emulsion treatment step may be performed such that a content or an OPU content of an emulsion in a material satisfies the range described above.

[0234] For example, drying treatment (h2) may be additionally performed. Such drying may be performed, for example, at a temperature ranging from 100 °C to 130 °C. A drying treatment manner or method is not particularly limited, and known technologies may be used. For example, the drying may be performed by applying hot air to a lyocell material or allowing a lyocell material to pass through a temperature-controlled room or leaving the lyocell material for a certain period of time.

[0235] In an aspect, the present disclosure provides a lyocell material obtained through the method of preparing a lyocell material as described above.

[0236] In an aspect, the present disclosure provides a lyocell material obtainable through the method of preparing a lyocell material as described above.[Smoking article]

[0237] Although not particularly limited, a lyocell material prepared through the method may be included in a smoking article. The smoking article may be an aerosol-generating article. The aerosol-generating article may include an aerosol-generating material or an aerosol-forming substrate.

[0238] For example, the lyocell material may be included in a combustion-type cigarette. Further, the lyocell material may be, for example, included in a heated cigarette, and the heated cigarette may be used together with an aerosol generating device (not shown).

[0239] For example, when used as a heated smoking article, the smoking article may be separately inserted into the aerosol generating device. Here, the aerosol generating device may include an accommodation groove in which an aerosol-generating article may be accommodated, and in addition, may include a heater for heating the aerosol-generating article to generate aerosol, a control unit for controlling the overall operation of the aerosol generating device, a battery for providing power used for operating the aerosol generating device, and a detector for recognizing that the aerosol-generating article has been inserted into the aerosol generating device.

[0240] The smoking article may include a tobacco medium portion, a filter for a smoking article, and a wrapper, wherein the filter for a smoking article may be positioned at one end portion of the tobacco medium portion, for example, a rear end portion or a front end portion. The tobacco medium portion and the filter for a smoking article may each include a single segment or may each independently include a plurality of segments.

[0241] The tobacco medium portion includes a tobacco material, and the tobacco material includes nicotine. In addition, the tobacco medium portion may additionally include excipients.

[0242] The excipients may include a binder, a filler, and other additives. For example, a tobacco medium included in the tobacco medium portion may be prepared in the form of granules including a tobacco material, an excipient, and the like.

[0243] For example, a filler may be additionally included to constantly maintain the shape, strength, and mass of the tobacco medium portion. For example, the lyocell material may be included in the tobacco medium portion. In addition, the lyocell material may be used as a filler.

[0244] The wrapper may be subdivided into cigarette paper for wrapping the tobacco medium portion, filter wrapping paper for wrapping the filter, and a tipping wrapper for coupling the tobacco medium portion and the filter.[Filter for smoking article]

[0245] A lyocell material may be used in a filter for a smoking article. The lyocell material may be lyocell tow. In an example, the lyocell tow includes lyocell multifilaments to which crimps have been imparted.

[0246] According to an aspect, the present application relates to a filter for a smoking article. The filter for a smoking article may include a lyocell material, and the lyocell material may be identical to that described above. In addition, the filter for a smoking article may include lyocell tow, and the lyocell tow may be identical to that described above.

[0247] In addition, the lyocell material may include an emulsion in a content of 0.1 wt% or more with respect to 100 wt% of the total weight of the lyocell material. In addition, an emulsion component and a content according to a specific example of the present application are as described above.

[0248] For example, a single fiber fineness of a filament constituting the lyocell multifilament may be in a range of 1.5 denier to 8.0 denier. A specific numerical value is as described above.

[0249] For example, the lyocell multifilament to which crimps have been imparted may be a lyocell material having a total fineness of 15,000 denier to 55,000 denier, and preferably, the lyocell multifilament may be lyocell tow. A specific numerical value is as described above.

[0250] In an example, the lyocell multifilament to which crimps have been imparted may have 3.94 to 19.69 crimps per cm (10 to 50 crimps per inch). A specific numerical value is as described above.

[0251] For example, the filter for a smoking article may further include a binder on a surface of the lyocell multifilament to which crimps have been imparted or between the lyocell multifilaments to which crimps have been imparted. The binder increases the hardness of a filter for a smoking article prepared from tow, thereby preventing problems such as filter jamming during a process of preparing a filter or a process of preparing a tobacco. Types, components, and contents of available binders are as described above.

[0252] For example, the filter for a smoking article may further include wrapping paper (which may be referred to as wrapper paper, filter paper, or filter wrapping paper). For example, the wrapping paper may be porous paper or non-porous paper that may wrap the above-described lyocell tow and may maintain a filter shape (for example, a cylinder or circular column).

[0253] In some embodiments of the present application, the filter for a smoking article may have a certain shape and a certain size.

[0254] For example, the filter may have a rod shape. For example, the filter for a smoking article may have a shape such as a cylinder.

[0255] In addition, the filter may have a length of, for example, 10 nm to 50 mm. For example, the length of the filter may have a lower limit of 15 mm or more, 20 mm or more, 25 mm or more, 30 mm or more, 35 mm or more, 40 mm or more, or 45 mm or more, and an upper limit of 45 mm or less, 40 mm or less, 35 mm or less, 30 mm or less, 25 mm or less, 20 mm or less, or 15 mm or less.

[0256] In some embodiments of the present application, the filter having the length may have a circular cross section, and a circumference of the circular cross section may be in a range of 10 nm to 40 mm. For example, the circumference of the filter may have a lower limit of 15 mm or more, 20 mm or more, 25 mm or more, 30 mm or more, or 35 mm or more, and an upper limit of 35 mm or less, 30 mm or less, 25 mm or less, 20 mm or less, or 15 mm or less.

[0257] For example, the filter for a smoking article may include lyocell tow and filter wrapping paper. The lyocell tow and the filter wrapping paper are as described above, and thus descriptions thereof are omitted.

[0258] The wrapping paper may be porous paper or non-porous paper that may wrap the above-described lyocell tow and may maintain a filter shape (for example, a cylinder or circular column).

[0259] For example, when porous wrapping paper is used, the wrapping paper may have a porosity of 10 coresta unit (CU) to 50,000 CU. A coresta unit may be defined as a volume flow rate (cm 3< min -1< ) of air passing through a 1 cm 2< substrate sample (that is, porous wrapping paper) at a pressure difference of 1 kPa. A lower limit of the porosity of the wrapping paper may be, for example, 1,000 CU or more, 5,000 CU or more, 10,000 CU or more, 15,000 CU or more, 20,.000 CU or more, 25,000 CU or more, 30,000 CU or more, 35,000 CU or more, 40,000 CU or more, or 45,000 CU or more, and an upper limit thereof may be, for example, 45,000 CU or less, 40,000 CU or less, 35,000 CU or less, 30,000 CU or less, 25,000 CU or less, or 20,000 CU or less. In some embodiments of the present application, the wrapping paper may have a porosity in a range of 22,000 CU to 26,000 CU or 23,000 CU to 25,000 CU.

[0260] For example, a basis weight of the wrapping paper may be in a range of 15 g / m 2< to 60 g / m 2< . A lower limit of the basis weight of the wrapping paper may be, for example, 20 g / m 2< or more, 25 g / m 2< or more, 30 g / m 2< or more, 35 g / m 2< or more, 40 g / m 2< or more, 45 g / m 2< or more, 50 g / m 2< or more, or 55 g / m 2< or more, and an upper limit thereof may be, for example, 55 g / m 2< or less, 50 g / m 2< or less, 45 g / m 2< or less, 40 g / m 2< or less, 35 g / m 2< or less, 30 g / m 2< or less, 25 g / m 2< or less, or 20 g / m 2< or less. In some embodiments of the present application, the wrapping paper may have a basis weight of 16 g / m 2< or more, 17 g / m 2< or more, 18 g / m 2< or more, 19 g / m 2< or more, 20 g / m 2< or more, or 21 g / m 2< or more, and 25 g / m 2< or less, 24 g / m 2< or less, 23 g / m 2< or less, 22 g / m 2< or less, or 21 g / m 2< or less.

[0261] Although not particularly limited, a weight of a filter having a rod shape may be 50 mg or more. The weight of the filter may have, for example, a lower limit of 100 mg or more, 150 mg or more, or 200 mg or more, and an upper limit of 500 mg or less, 450 mg or less, 400 mg or less, 350 mg or less, 300 mg or less, 250 mg or less, or 200 mg or less.

[0262] Other filters for a smoking article and materials included therein are as described above, and thus descriptions thereof are omitted.[Method of preparing filter for smoking article]

[0263] For example, the present application relates to a method of preparing a filter for a smoking article. The method may be a method of preparing a filter for a lyocell smoking article as described above and may be a method including the above-described method of preparing a lyocell material.

[0264] Regarding the method of preparing a filter for a smoking article, the remaining steps excluding preparing of a filter are the same as steps described in the lyocell material described above, and thus descriptions thereof are omitted. In addition, descriptions overlapping the above descriptions are also omitted.

[0265] The preparing of the filter may be appropriately performed by a person skilled in the art according to a known method. For example, the filter may be prepared by forming wrapping paper filled with a lyocell material into a rod shape. Alternatively, the filter may be prepared by cutting, into an appropriate length, filter paper which has a rod shape and is filled with a lyocell material. The wrapping paper is as described above.

[0266] Although not particularly limited, before the filter paper is filled with the lyocell material, the lyocell material may be further subjected to opening or plasticizer treatment. A surface area of the lyocell material may be increased by opening the lyocell material. For example, the lyocell material may be opened by applying an external force in a longitudinal direction, a width direction, and / or a thickness direction.

[0267] Preferably, the lyocell material used in preparing a filter for a smoking article may be lyocell tow.

[0268] Although not particularly limited, the filter for a smoking article may additionally include known cellulose acetate multifilaments at a level that does not impede the purpose of the present disclosure. The cellulose acetate multifilament may be mixed with a lyocell multifilament. The cellulose acetate multifilament may be included in a segment distinguished from a segment including the lyocell multifilament.Advantageous Effects of Invention

[0269] According to the present application, provided are a lyocell material for a filter for a smoking article, which is capable of replacing commercialized cellulose acetate (CA), and a filter for a smoking article including the same. Specifically, by satisfying a certain FPI, the post-processing properties of a lyocell material, for example, unwinding properties, may be improved. As a result, process costs consumed to prepare a filter for a smoking article may be reduced.Mode for the Invention

[0270] Hereinafter, the operations and effects of the present disclosure will be described in more detail through specific examples of the present disclosure. However, this is presented as an example of the present disclosure, and the scope of the present disclosure is not limited thereby.

[0271] A lyocell material was prepared through processes as described in Preparation Example below. Conditions not specifically described are within the scope of the above description.[Preparation Example]

[0272] Cellulose pulp having an alpha-cellulose content of 93.9 % and a DPw of 820 was mixed with an NMMO / H 2 O solvent having a propyl gallate content of 0.01 wt% to prepare a spinning dope for preparing tow having a concentration of 11 wt%. While a spinning temperature of a spinning nozzle was maintained at 110 °C, a discharge amount and a spinning speed were appropriately adjusted, and the spinning dope was spun.

[0273] The spinning dope with a filament phase discharged from the spinning nozzle was supplied to a coagulating solution (a coagulating solution having a concentration of 75 wt% water and 25 wt% NMMO and a temperature of about 25 °C) in a coagulation tank through an air gap section. In this case, cooling air in the air gap section primarily solidifies the spinning dope at a temperature of 8 °C and an air flow rate of 120 Nm 3< / h. In addition, the concentration of the coagulating solution was continuously monitored by using a sensor and a refractometer.

[0274] A coagulated lyocell filament was washed. Specifically, the filament was introduced between traction rollers, and NMMO remaining in the filament was removed by using a washing solution sprayed from a washing device. Then, the washed filament was immersed inside a bath designed to have a certain emulsion concentration. Afterwards, the filament was prepared to satisfy a moisture content of 150 % to 400 %.

[0275] The filament was treated at a pressure of 19.6 N / cm 2< (2 kgf / cm 2< ) through a nip roll installed in a bath discharge portion and put into a crimp machine to impart wrinkles. Specifically, pressure of a press roller was set to 24.52 N / cm 2< (2.5 kgf / cm 2< ), and pressure of a doctor blade was set to 4.90 N / cm 2< (0.5 kgf / cm 2< ) to impart crimps to lyocell materials.

[0276] The lyocell materials to which crimps have been imparted were sequentially stacked in box-shaped containers, and each container was pressed at a pressure of 196 N / cm 2< to 588 N / cm 2< (20 kgf / cm 2< to 60 kgf / cm 2< ).

[0277] Prepared lyocell tow has a single fiber fineness of 2.22 dtex to 8.88 dtex (2.0 denier to 8.0 denier), a total fineness of 3,333 tex to 6,110 tex (30,000 denier to 55,000 denier), and the number of crimps of 5.91 ea / cm to 18.05 ea / cm (15 ea / inch to 55 ea / inch).Examples 1 to 6

[0278] Lyocell materials were prepared according to Preparation Example, and values of a moisture content, pressing pressure, crimp energy CrE, porosity Po, density A, and density B of a filament were as shown in Table 1 below.Comparative Examples 1 to 5

[0279] Lyocell materials were prepared according to Preparation Example and values of a moisture content, pressing pressure, crimp energy CrE, porosity Po, density A, and density B of a filament were as shown in Table 1 below.

[0280] The value of crimp energy of each of Examples and Comparative Examples was measured by using a UTM (Model No. 5566 manufactured by Intron Ltd.,). In order to measure the value of crimp energy, a sample with a length of about 20 was taken from each lyocell material. Each taken sample was mounted on a dedicated jig and weighted to have an initial load of 0.98 N (100 gf). Each sample was weighted until crimps were not identified. The value of crimp energy was calculated by converting a weight weighted when crimps were not identified.

[0281] Meanwhile, the porosity of each of Examples and Comparative Examples was obtained by measuring an apparent density (density A) and a true density (density B) and performing a calculation according to Equation 2 below. 1 − density A / density B × 100

[0282] Density A was obtained by dividing a weight (g) of each of Examples and Comparative Examples by a volume (cm 3< ) of a container containing each of Example and Comparative Example. Density B was measured by using a true specific density meter (model number: AccuPyc II 1340 manufactured by Micromeritics). Gas for analysis was He(g), an equilibrium velocity was about 0.005 psig / min, an expansion volume was about 9.2169 cm 3< , and a cell volume was about 0.0029 g / cm 3< . [Table 1]TargetMoisture content (%)Pressing pressure(N / cm 2< )CrE (mJ)Po (%)Density A (g / cm 3< )Density B (g / cm 3< )Examples120627478265.10.5181.484622882941,46565.20.5131.47303231333.296156.90.6351.47374335352.81,62256.80.6401.48245175431.258044.20.8231.47356312470.4150240.20.8831.4756Comparative Examples12359881286.50.2001.4785285352.835257.50.6311.48603245646.880514.31.2751.48734405372.42,38553.80.6881.4876580117.635083.20.2501.4876 <Evaluation Example 1: Evaluation of filter manufacturability and filterability according to FPI>

[0283] For the lyocell materials of Examples 1 to 6 and Comparative Examples 1 to 5, an FPI was calculated according to Equation 1 below. 2 × CrE / Po

[0284] Meanwhile, when the preparation of a filter for a smoking article from a lyocell material is performed continuously without interruption, filter manufacturability was evaluated to be good. On the other hand, when the preparation of a filter was stopped, or a prepared filter was unsuitable as a filter for a smoking article, filter manufacturability was evaluated to be poor.

[0285] In addition, the maximum suction resistance of each filter for a smoking article was measured according to the KS H ISO 6565 standard. Respective filters had a uniform diameter and all had a rod shape.

[0286] Evaluation results of the filter manufacturability and maximum suction resistance of the lyocell materials of Examples 1 to 6 and Comparative Examples 1 to 5 are as shown in Table 2 below. [Table 2]TargetFPIFilter manufacturabilityMaximum suction resistance (mmHG / rod)Examples124.0Good458244.9Good683333.8Good554457.1Good754526.3Good511674.8Good812Comparative Examples118.8Poor-212.2Poor3553112.8Poor-488.7Poor-58.4Poor-

[0287] It was found that the lyocell materials of Examples 1 to 6 all satisfied an FPI range of 19 to 88. The preparation of filters for a smoking article from the lyocell materials of Examples 1 to 6 were smoothly performed, and it was confirmed that filters including the lyocell materials of Examples 1 to 6 could provide maximum suction resistance suitable for filters for a smoking article.

[0288] On the other hand, it was found that an FPI of Comparative Examples 1, 2, and 5 was less than 19. In particular, the preparation of filters from the lyocell materials of Comparative Example 1 and Comparative Example 5 was not possible. Specifically, in the lyocell materials of Comparative Examples 1 and 5, the clumping between filaments was confirmed, and it was confirmed that unwinding properties were significantly reduced. The lyocell material of Comparative Example 2 was unwound, but it was found that a filter including the lyocell material of Comparative Example 2 did not provide sufficient filterability as a filter for a smoking article.

[0289] In addition, it was found that an FPI of Comparative Example 3 and Comparative Example 4 exceeded 88. As a result, the preparation of filters from the lyocell materials of Comparative Example 3 and Comparative Example 4 was not possible. Specifically, during an unwinding process of the lyocell material of Comparative Example 3, cutting occurred and a filter preparation process was stopped. In the case of the lyocell material of Comparative Example 4, opening could not be sufficiently performed, and it was found that a filter burst due to the clumping of the lyocell material in the filter.

Examples

preparation example

[Preparation Example]

[0272]Cellulose pulp having an alpha-cellulose content of 93.9 % and a DPw of 820 was mixed with an NMMO / H 2 O solvent having a propyl gallate content of 0.01 wt% to prepare a spinning dope for preparing tow having a concentration of 11 wt%. While a spinning temperature of a spinning nozzle was maintained at 110 °C, a discharge amount and a spinning speed were appropriately adjusted, and the spinning dope was spun.

[0273]The spinning dope with a filament phase discharged from the spinning nozzle was supplied to a coagulating solution (a coagulating solution having a concentration of 75 wt% water and 25 wt% NMMO and a temperature of about 25 °C) in a coagulation tank through an air gap section. In this case, cooling air in the air gap section primarily solidifies the spinning dope at a temperature of 8 °C and an air flow rate of 120 Nm 3< / h. In addition, the concentration of the coagulating solution was continuously monitored by using a sensor and a refractometer...

examples 1 to 6

Examples 1 to 6

[0278]Lyocell materials were prepared according to Preparation Example, and values of a moisture content, pressing pressure, crimp energy CrE, porosity Po, density A, and density B of a filament were as shown in Table 1 below.

examples124.0

Examples124.0Good458

244.9Good683

333.8Good554

457.1Good754

526.3Good511

674.8Good812

Technical Field

[0001] The present application relates to a lyocell material, a filter including the same, a smoking article, and a method of preparing the lyocell material.Background Art

[0002] Until now, cellulose acetate fibers have been mainly used as tobacco filter materials. Cellulose acetate is known to be a biodegradable material, but filters for a smoking article, made of cellulose acetate, remain in their original form for 1 to 2 years even after being buried in soil, and it takes a considerable amount of time for the filters to completely biodegrade. Considering the amount and toxicity of tobacco products that are discarded and left in the living environment as well as tobacco products that are collected as waste after being used for smoking and then buried in a landfill, there is a need to further improve the biodegradability of filters for smoking articles. Accordingly, lyocell, which is more environmentally friendly, has recently been chosen as a material to replace cellulose acetate.Disclosure of InventionTechnical Problem

[0003] An object of the present application is to provide a lyocell material capable of replacing cellulose acetate commercialized for a filter for a smoking article.

[0004] Another object of the present application is to provide a lyocell material for a filter for a smoking article, of which a preparation process is environmentally friendly and which has excellent biodegradability when discarded.

[0005] Another object of the present application is to provide a lyocell filter for a smoking article.

[0006] Another object of the present application is to provide a smoking article (for example, a cigarette) including a lyocell filter.Solution to Problem

[0007] According to aspects of the present application, a lyocell material, a filter including the same, a smoking article, and the like may be provided.

[0008] According to an aspect, provided is a lyocell material including lyocell multifilaments to which crimps have been imparted, wherein the lyocell material has a filter process index (FPI) of 19 to 88, represented by Equation 1: 2 × CrE / Po wherein, in Equation 1, CrE is crimp energy, and Po is porosity represented by Equation 2 below: 1 − density A / density B × 100 wherein, in Equation 2, density A is an apparent density of the lyocell material, and density B is a true density of the lyocell material.

[0009] According to another aspect of the present application, a filter for a lyocell smoking article including the lyocell material may be provided.

[0010] According to another aspect of the present application, a smoking article including the lyocell material or the filter may be provided.

[0011] According to another aspect of the present application, a method of preparing the lyocell material, a filter including the same, and a smoking article may be provided.

[0012] As used herein, the term "smoking article" may refer to an article such as a tobacco (cigarette) or a cigar capable of generating aerosol. In this regard, the smoking article may include an aerosol-generating material or an aerosol-forming substrate. In addition, the smoking article may include a solid material based on a tobacco raw material such as a tobacco leaf, a cut tobacco, or a reconstituted tobacco. In addition, the smoking material may include a volatile compound.

[0013] As used herein, the term "crimp" or "crimped" may refer to the waviness, curliness, or undulating configuration imparted to materials such as fibers, (mono)filaments, multifilaments and / or yarns, inherently and / or through mechanical, thermal, or chemical processes. A crimp may be characterized by periodic deviations from a straight linear axis along the length of the material, fiber, (mono)filament, multifilament and / or yarn. One crimp of a material, fiber, (mono)filament, multifilament and / or yarn may be defined as one repetition unit of said periodic deviation. The presence of crimp contributes to properties such as elasticity, bulk, resilience, and texture in the material and fabrics made from it.

[0014] Unless specifically defined otherwise in the specification, when the properties of lyocell materials, filters for a smoking article, and components or compositions related thereto are affected by a temperature, the temperature at which the properties are confirmed or measured may be room temperature. In this case, the room temperature may be a temperature which is not particularly lowered or raised and may be, for example, in a range of 10 °C to 35 °C, specifically in a range of 15 °C to 35 °C or 20 °C to 30 °C, or may be about 25 °C.

[0015] Hereinafter, the present application is described in more detail.

[0016] The present application relates to a lyocell material. The lyocell material may be used in a smoking article, and although not particularly limited, the lyocell material may be used in a filter for a smoking article.

[0017] According to an aspect, provided is a lyocell material including lyocell multifilaments to which crimps have been imparted, wherein the lyocell material has an FPI of 19 to 88, represented by Equation 1. 2 × CrE / Po

[0018] In Equation 1, CrE is crimp energy, and Po is porosity represented by Equation 2 below. 1 − density A / density B × 100

[0019] In Equation 2, density A is an apparent density of the lyocell material, and density B is a true density of the lyocell material.

[0020] In some embodiments, the FPI may be in a range of 24 to 75.

[0021] In some embodiments, CrE in Equation 1 may be in a range of 400 mJ to 2,300 mJ.

[0022] In some embodiments, CrE in Equation 1 may be in a range of 550 mJ to 1,650 mJ.

[0023] In some embodiments, CrE in Equation 1 may be a value measured from a sample with a size of about 20 cm taken from a lyocell material by using a universal testing machine (UTM). Each sample was weighted until crimps were not identified. CrE may be a value obtained by converting, into energy, a weight added until a crimp is not identified from a sample. The expression "until a crimp is not identified from a sample" means that the waviness, curliness, or undulating configuration, as described above with regard to the term "crimp", is not shown by the sample anymore.

[0024] In some embodiments, Po in Equation 1 may be in a range of 15 % to 83 %.

[0025] In some embodiments, Po in Equation 1 may be in a range of 40 % to 70 %.

[0026] In some embodiments, density A in Equation 2 may be in a range of 0.300 g / cm 3< to 1.200 g / cm 3< .

[0027] In some embodiments, density A in Equation 2 may be in a range of 0.500 g / cm 3< to 0.900 g / cm 3< .

[0028] In some embodiments, density A in Equation 2 may be a value obtained by dividing a weight of a lyocell material by a volume of a container filled with the lyocell material. The shape of the container is not particularly limited. for example, the container may be box-shaped.

[0029] In some embodiments, density B in Equation 2 may be in a range of 1.40 g / cm 3< to 1.50 g / cm 3< .

[0030] In some embodiments, density B in Equation 2 may be in a range of 1.470 g / cm 3< to 1.490 g / cm 3< .

[0031] In some embodiments, density B in Equation 2 may be a value measured from a lyocell material by using a true specific density meter, in particular a pycnometer, under conditions in which gas for analysis is He (g), an equilibrium velocity is about 0.005 psig / min, an expansion volume is about 9.2169 cm 3< , and a cell volume is about 0.0029 g / cm 3< .

[0032] In some embodiments, the lyocell material may satisfy both Conditions 1 and 2 below.

[0033] [Condition 1] CrE in Equation 1 is in a range of 400 mJ to 2,300 mJ.

[0034] [Condition 2] Po in Equation 1 is in a range of 15 % to 83 %.

[0035] In some embodiments, the lyocell material may satisfy at least one of Conditions 1-1 and 2-1 below.

[0036] [Condition 1-1] CrE in Equation 1 is in a range of 550 mJ to 1,650 mJ

[0037] [Condition 2-1] Po in Equation 1 is in a range of 40 % to 70 %.

[0038] In some embodiments, the number of crimps may be 3.94 ea / cm (10 ea / inch) to 23.64 ea / cm (60 ea / inch).

[0039] In some embodiments, the number of crimps may be 9.85 ea / cm to 19.71 ea / cm (25 ea / inch to 50 ea / inch).

[0040] In some embodiments, a single fiber fineness of the lyocell multifilament may be in a range of 1.67 dtex to 12.21 dtex (1.5 denier to 11.0 denier).

[0041] In some embodiments, the single fiber fineness of the lyocell multifilament may be in a range of 2.22 dtex to 6.66 dtex (2.0 denier to 6.0 denier).

[0042] In some embodiments, the lyocell material may have a total fineness of1,667 tex to 6,111 tex (15,000 denier to 55,000 denier).

[0043] In some embodiments, the lyocell material may have a total fineness of 2,222 tex to 5,555 tex (20,000 denier to 50,000 denier).

[0044] In some embodiments, the lyocell multifilament may include one or more monofilaments, and one or more of the monofilaments may have a multi-lobal cross section.

[0045] In some embodiments, the lyocell multifilament may include one or more monofilaments, and all of the monofilaments may have a multi-lobal cross section.

[0046] In some embodiments, the lyocell material may be lyocell tow.

[0047] In some embodiments, the lyocell material may be used for a filter for a smoking article.

[0048] In some embodiments, the lyocell material may not not for use in tire cords or garments.

[0049] In some embodiments, the lyocell material may be a lyocell laminate.

[0050] In addition, according to another aspect, provided is a filter for a smoking article including any one of the lyocell materials described in this application.

[0051] Furthermore, according to another aspect, provided is a smoking article including any one of the filters for a smoking article described in this application.

[0052] In addition, provided is a method of preparing a lyocell material, which includes lyocell dope spinning; coagulating, and obtaining lyocell multifilament; washing; emulsion treatment; and crimp imparting, wherein the method further includes stacking and pressing, and an FPI measured from the lyocell material after the stacking and pressing is in a range of 19 to 88.

[0053] In some embodiments, a pressing pressure of the stacking and pressing may be in a range of 196 N / cm 2< to 588 N / cm 2< (20 kgf / cm 2< to 60 kgf / cm 2< ).

[0054] In some embodiments, a moisture content of the lyocell material measured before the crimp imparting may be in a range of 150 % to 400 %.

[0055] A lyocell material according to some embodiments may have an FPI of 19 to 88, represented by Equation 1 below. 2 × CrE / Po

[0056] In Equation 1, CrE is crimp energy, and Po is porosity represented by Equation 2 below. 1 − density A / density B × 100

[0057] In Equation 2, density A is an apparent density of the lyocell material, and density B is a true density of the lyocell material.

[0058] While researching the post-processing properties of a lyocell material, the applicants have found that the post-processing properties of the lyocell material depend on the crimp energy and porosity of the lyocell material and thus have found that the post-processing properties of the lyocell material may be adjusted by adjusting Equation 1 which includes crimp energy and porosity as variables. In particular, it has been confirmed that when an FPI is less than 19 or more than 88, the unwinding properties of the lyocell material may be significantly reduced.

[0059] Specifically, when an FPI is less than 19, the clumping of the lyocell material may occur during an unwinding process of the lyocell material, or the blooming of the lyocell material may not occur sufficiently during and / or after unwinding. As a result, the filterability of a filter for a smoking article including a lyocell material having an FPI of less than 19 may be insufficient. More specifically, a filter for a smoking article including a lyocell material having an FPI of less than 19 may have a maximum suction resistance of less than 400 mmHG / rod and may have filterability that is unsuitable for use as a filter for a smoking article.

[0060] Specifically, when the FPI exceeds 88, excessive energy may be required for opening and / or unwinding, and the opening and / or unwinding of the lyocell material may not be sufficiently performed. As a result, the cutting of the lyocell material may occur during an opening and / or unwinding process. In addition, the clumping of a lyocell material included in a filter for a smoking article may occur due to insufficient opening and / or unwinding, and the filter for a smoking article may burst due to the lyocell material.

[0061] Accordingly, the FPI represented by Equation 1 may be adjusted in a range of 19 to 88, thereby securing the processability of the lyocell material to a certain level or more. Furthermore, the filterability of a filter for a smoking article including the lyocell material may be implemented at a certain level or more.[Lyocell material]

[0062] According to an aspect, provided is a lyocell material including lyocell multifilaments to which crimps have been imparted, wherein the lyocell material has an FPI of 19 to 88, represented by Equation 1. 2 × CrE / Po

[0063] In Equation 1, CrE is crimp energy, and Po is porosity represented by Equation 2 below. 1 − density A / density B × 100

[0064] In Equation 2, density A is an apparent density of the lyocell material, and density B is a true density of the lyocell material.

[0065] Since the lyocell material satisfies Equation 1, the post-processing properties of the lyocell material, for example, unwinding properties, may be improved, and openability may be improved. As a result, process costs consumed to prepare a filter for a smoking article may be reduced.

[0066] Specifically, the lyocell material may be post-processed to be included in a filter for a smoking article. The post-processing may include unwinding the lyocell material and / or opening the lyocell material. In the case of a lyocell material of which an FPI represented by Equation 1 is not in a range of 19 to 88, the lyocell material may have insufficient unwinding properties and / or openability. For example, the lyocell material may not be unwound uniformly and continuously. As a result, a process of preparing a filter for a smoking article from a lyocell material may be delayed, and the filterability of a filter for a smoking article may be degraded.

[0067] In addition, the post-processing of the lyocell material may include applying an external force to the lyocell material to induce the blooming of the lyocell material. In the case of a lyocell material of which an FPI represented by Equation 1 is not in a range of 19 to 88, the blooming of the lyocell material may not occur smoothly.

[0068] More specifically, in the case of a lyocell material of which an FPI represented by Equation 1 is not in a range of 19 to 88, the lyocell material may be clumped or cut during an unwinding process of the lyocell material. In addition, the blooming of the lyocell material may not be performed uniformly due to the clumping of the lyocell material. As a result, the filterability of a filter for a smoking article may be degraded, or manufacturing thereof may become impossible, and a process of preparing a filter for a smoking article may be delayed or stopped.

[0069] In some embodiments, an upper limit of the FPI may be 85 or less, 82.5 or less, 80 or less, 77.5 or less, 75 or less, 72.5 or less, 70 or less, 67.5 or less, 65 or less, 62.5 or less, 60 or less, 57.5 or less, 55 or less, 52.5 or less, 50 or less, 47.5 or less, 45 or less, 42.5 or less, 40 or less, 37.5 or less, 35 or less, 32.5 or less, 30 or less, 27.5 or less, or 25 or less. By satisfying the upper limit of the FPI, the cutting of the lyocell material may be prevented, and the clumping of the lyocell material may be suppressed.

[0070] In addition, in some embodiments, a lower limit of the FPI may be 20 or more, 22.5 or more, 25 or more, 27.5 or more, 30 or more, 32.5 or more, 35 or more, 37.5 or more, 40 or more, 42.5 or more, 45 or more, 47.5 or more, 50 or more, 52.5 or more, 55 or more, 57.5 or more, 60 or more, 62.5 or more, 65 or more, 67.5 or more, 70 or more, or 72.5 or more. By satisfying the lower limit of the FPI, the unwinding defect of the lyocell material may be suppressed, and a filter for a smoking article including the same may provide filterability of a certain level or more (for example, a suction resistance of 400 mmHG / rod or more).

[0071] In some embodiments, the FPI may be in a range of 24 to 75. Preferably, the FPI may be in a range of 24 to 65, 24 to 60, 24 to 55, 24 to 50, 24 to 45, 24 to 40, 24 to 35, 24 to 30, 25 to 65, 30 to 65, 35 to 65, 40 to 65, 45 to 65,50 to 65, or 55 to 65, and more preferably 60 to 65.

[0072] In some embodiments, CrE in Equation 1 may be in a range of 400 mJ to 2,300 mJ. Since CrE satisfies such a numerical range, the filterability of a filter for a smoking article and the preparation processability of the filter for a smoking article may be harmoniously improved.

[0073] In some embodiments, an upper limit of CrE may be 2,200 mJ or less, 2,100 mJ or less, 2,000 mJ or less, 1,900 mJ or less, 1,800 mJ or less, 1,700 mJ or less, 1,600 mJ or less, 1,500 mJ or less, 1,400 mJ or less, 1,300 mJ or less, 1,200 mJ or less, 1,100 mJ or less, 1,000 mJ or less, 900 mJ or less, 800 mJ or less, 700 mJ or less, or 600 or less. Since the lyocell material satisfies the upper limit of CrE, the openability of the lyocell material may be improved, and the preparation processability of a filter for a smoking article including the lyocell material may be secured.

[0074] In some embodiments, a lower limit of CrE may be 500 mJ or more, 600 mJ or more, 700 mJ or more, 800 mJ or more, 900 mJ or more, 1,000 mJ or more, 1,100 mJ or more, 1,200 mJ or more, 1,300 mJ or more, 1,400 mJ or more, 1,500 mJ or more, or 1,600 or more. Since the lyocell material satisfies the lower limit of CrE, a filter for a smoking article including the same may provide filterability of a certain level or more (for example, a suction resistance of 400 mmHG / rod or more).

[0075] In some embodiments, CrE in Equation 1 may be in a range of 550 mJ to 1,650 mJ. Preferably, CrE may be in a range of 550 mJ to 1,600 mJ, 550 mJ to 1,500 mJ, 550 mJ to 1,400 mJ, 550 mJ to 1,300 mJ, 550 mJ to 1,200 mJ, 550 mJ to 1,100 mJ, 550 mJ to 1,000 mJ, 550 mJ to 900 mJ, 550 mJ to 800 mJ, 550 mJ to 700 mJ, 550 mJ to 600 mJ, 600 mJ to 1,600 mJ, 700 mJ to 1,600 mJ, 800 mJ to 1,600 mJ, 900 mJ to 1,600 mJ, 1,000 mJ to 1,600 mJ, 1,100 mJ to 1,600 mJ, 1,200 mJ to 1,600 mJ, 1,300 mJ to 1,600 mJ, or 1,400 mJ to 1,600 mJ, preferably 1,500 mJ to 1,600 mJ.

[0076] In each exemplary lyocell material, CrE in Equation 1 may be a value measured from a sample with a size of about 20 cm taken from a lyocell material by using a UTM, and CrE may be a value obtained by converting, into energy, a weight added until a crimp is not identified from a sample, as described above.

[0077] For example, Model No. 5566 manufactured by Intron Ltd., may be used as the UTM. In addition, an initial load applied to the sample may be about 0.98 N (100 gf).

[0078] In some embodiments, Po in Equation 1 may be in a range of 15 % to 83 %. Since Po satisfies such a numerical range, the unwinding properties of the lyocell material may be increased, and simultaneously, the cutting of the lyocell material may be prevented.

[0079] In some embodiments, an upper limit of Po may be 80 % or less, 78 % or less, 76 % or less, 74 % or less, 72 % or less, 70 % or less, 68 % or less, 66 % or less, 65 % or less, 64 % or less, 62 % or less, 60 % or less, 58 % or less, 56 % or less, 55 % or less, 54 % or less, 52 % or less, 50 % or less, 48 % or less, 46 % or less, 45 % or less, 44 % or less, or 42 % or less. Since Po satisfies the upper limit, the unwinding properties of the lyocell material may be improved, and the clumping of the lyocell material may be suppressed.

[0080] In some embodiments, a lower limit of Po may be 16 % or more, 18 % or more, 20 % or more, 22 % or more, 24 % or more, 26 % or more, 28 % or more, 30 % or more, 32 % or more, 34 % or more, 36 % or more, 38 % or more, 40 % or more, 42 % or more, 44 % or more, 46 % or more, 48 % or more, 50 % or more, 52 % or more, 54 % or more, 56 % or more, 58 % or more, 60 % or more, 62 % or more, 64 % or more, or 65 % or more. Since the lyocell material satisfies the lower limit of Po, the cutting of the lyocell material during an unwinding process may be suppressed. For example, by satisfying the lower limit of Po, the cutting of a lyocell monofilament due to tension may be suppressed.

[0081] In some embodiments, Po in Equation 1 may be in a range of 40 % to 70 %. Preferably, Po may be in a range of 40 % to 68 %, 40 % to 66 %, 40 % to 64 %, 40 % to 62 %, 40 % to 60 %, 40 % to 58 %, 40 % to 56 %, 40 % to 54 %, 40 % to 52 %, 40 % to 50 %, 40 % to 48 %, 40 % to 46 %, 40 % to 44 %, 40 % to 42 %, 42 % to 68 %, 44 % to 68 %, 46 % to 68 %, 48 % to 68 %, 50 % to 68 %, 52 % to 68 %, 54 % to 68 %, 56 % to 68 %, 58 % to 68 %, 60 % to 68 %, 62 % to 68 %, or 64 % to 68 %, or more preferably 66 % to 68 %.

[0082] In some embodiments, density A in Equation 2 may be in a range of 0.300 g / cm 3< to 1.200 g / cm 3< . In some embodiments, an upper limit of density A may be 1.150 g / cm 3< or less, 1.100 g / cm 3< or less, 1.050 g / cm 3< or less, 1.000 g / cm 3< or less, 0.950 g / cm 3< or less, 0.900 g / cm 3< or less, 0.850 g / cm 3< or less, 0.800 g / cm 3< or less, 0.750 g / cm 3< or less, 0.700 g / cm 3< or less, or 0.650 g / cm 3< or less. In some embodiments, a lower limit of density A may be 0.350 g / cm 3< or more, 0.400 g / cm 3< or more, 0.450 g / cm 3< or more, 0.500 g / cm 3< or more, 0.550 g / cm 3< or more, 0.600 g / cm 3< or more, 0.650 g / cm 3< or more, 0.700 g / cm 3< or more, 0.750 g / cm 3< or more, 0.800 g / cm 3< or more, or 0.850 g / cm 3< or more. Preferably, density A in Equation 2 may be in a range of 0.500 g / cm 3< to 0.900 g / cm 3< .

[0083] In some embodiments, density A in Equation 2 may be a value obtained by dividing a weight of a lyocell material by a volume of a container filled with the lyocell material. For example, the container may be a hexagonal box.

[0084] In some embodiments, density B in Equation 2 may be in a range of 1.40 g / cm 3< to 1.50 g / cm 3< . In some embodiments, an upper limit of density B may be 1.495 g / cm 3< or less, 1.490 g / cm 3< or less, 1.485, 1.480 g / cm 3< or less, or 1.475 g / cm 3< or less. In some embodiments, a lower limit of density B may be 1.405 g / cm 3< or more, 1.410 g / cm 3< or more, 1.415 g / cm 3< or more, 1.420 g / cm 3< or more, 1.425 g / cm 3< or more, 1.430 g / cm 3< or more, 1.435 g / cm 3< or more, 1.440 g / cm 3< or more, 1.445 g / cm 3< or more, 1.450 g / cm 3< or more, 1.455 g / cm 3< or more, 1.460 g / cm 3< or more, 1.465 g / cm 3< or more, 1.470 g / cm 3< or more, 1.475 g / cm 3< or more, or 1.480 g / cm 3< or more. Preferably, density B in Equation 2 may be in a range of 1.470 g / cm 3< to 1.490 g / cm 3< .

[0085] In some embodiments, density B in Equation 2 may be a value measured from a lyocell material by using a true specific density meter, for example a pycnometer, under conditions in which gas for analysis is He(g), an equilibrium velocity is about 0.005 psig / min, an expansion volume is about 9.2169 cm 3< , and a cell volume is about 0.0029 g / cm 3< .

[0086] In some embodiments, the lyocell material may satisfy both Conditions 1 and 2 below. By simultaneously satisfying Conditions 1 and 2, the FPI of the lyocell material may be in a range of 19 to 88.

[0087] [Condition 1] CrE in Equation 1 is in a range of 400 mJ to 2,300 mJ.

[0088] [Condition 2] Po in Equation 1 is in a range of 15 % to 83 %.

[0089] In some embodiments, the lyocell material may satisfy at least one of Conditions 1-1 and 2-1 below. By simultaneously satisfying Conditions 1-1 and 2-1, the FPI of the lyocell material may be in a range of 24 to 75.

[0090] [Condition 1-1] CrE in Equation 1 is in a range of 550 mJ to 1,650 mJ

[0091] [Condition 2-1] Po in Equation 1 is in a range of 40 % to 70 %.[Multi-lobal cross section]

[0092] One or more of lyocell monofilaments included in a lyocell material of the present application may have a multi-lobal cross section. The term "multi-lobal" may mean that a shape of an outline of a cross section is not circular, and the term "cross section" may be a cross section obtained by cutting a lyocell monofilament in a direction virtually or actually perpendicular to a longitudinal direction of a filament.

[0093] An outline of the multi-lobal cross section may touch each of an imaginary first circle and an imaginary second circle. In addition, the imaginary second circle may be depicted inside the imaginary first circle.

[0094] The imaginary first circle may be a circle with the smallest area value among circles drawn to completely encompass one cross section of a monofilament. The imaginary second circle may be a circle with the largest area value among circles drawn inside a cross section of a monofilament.

[0095] When a circumscribed circle encompassing a cross section of a monofilament may be drawn, the imaginary first circle may be the circumscribed circle. When an inscribed circle may be drawn inside a cross section of a monofilament, the imaginary second circle may be the inscribed circle.

[0096] The multi-lobal cross section may have a shape including a plurality of protrusions and may be, for example, a Y-shaped cross section including three protrusions. It may be understood that the plurality of protrusions are formed as an integral type with the imaginary second circle as a central portion and have a shape of which an end touches the imaginary first circle.

[0097] A modified ratio of a monofilament may be defined by Equation 1 below. Modified ratio = r 1 / r 2

[0098] Here, r1 is a radius of the imaginary first circle, and r2 is a radius of the imaginary second circle.

[0099] For example, the radius of the imaginary first circle may be in a range of 4 µm to 40 µm, the radius of the imaginary second circle may be in a range of 2 µm to 14 µm, and the modified ratio may be in a range of 1.01 to 10.

[0100] In addition, a space occupancy ratio of a monofilament may be defined by Equation 2. Space occupancy ratio = S 1 / S 2 × 100 %

[0101] Here, S1 is an area of the imaginary first circle, and S2 is a cross-sectional area of a monofilament included in lyocell fiber.

[0102] For example, a space occupancy ratio of a monofilament having a multi-lobal cross section may be in a range of about 120 % to about 600 %.[Fineness]

[0103] A lyocell material of the present application may include a lyocell multifilament, and the lyocell multifilament may have a fineness suitable for preparing a filter for a smoking article and securing a function thereof.

[0104] For example, a single fiber fineness of a filament constituting the lyocell multifilament may be in a range of 1.67 dtex to 12.21 dtex (1.5 denier to 11.0 denier). In this case, the single fiber fineness of the filament refers to a fineness of a single monofilament separated from a multifilament. In other words, the single fiber fineness of a filament constituting the lyocell multifilament refers to the monofilament fineness.

[0105] The single fiber fineness of the filament may be, for example, 11.66 dtex (10.5 denier) or less, 11.12 dtex (10.0 denier) or less, 10.55 dtex (9.5 denier) or less, 9.99 dtex (9.0 denier) or less, 9.44 dtex (8.5 denier) or less, 8.88 dtex (8.0 denier) or less, 8.33 dtex (7.5 denier) or less, 7.78 dtex (7.0 denier) or less, 7.22 dtex (6.5 denier) or less, 6.67 dtex (6.0 denier) or less, 6.11 dtex (5.5 denier) or less, 5.56 dtex (5.0 denier) or less, 5.00 dtex (4.5 denier) or less, 3.89 dtex (3.5 denier) or less, 3.33 dtex (3.0 denier) or less, or 2.78 dtex (2.5 denier) or less. A lower limit of the single fiber fineness of the filament may be, for example, 2.22 dtex (2.0 denier) or more, 2.78 dtex (2.5 denier) or more, 3.33 dtex (3.0 denier) or more, 3.89 dtex (3.5 denier) or more, 4.44 dtex (4.0 denier) or more, 5.00 dtex (4.5 denier) or more, 5.56 dtex (5.0 denier) or more, 6.11 dtex (5.5 denier) or more, 6.67 dtex (6.0 denier) or more, 7.22 dtex (6.5 denier) or more, or 7.78 dtex (7.0 denier) or more. Satisfying such a range may be more advantageous in securing stable physical properties (for example, implementing hardness or suction resistance) and processability of a filter for a smoking article.

[0106] In some embodiments, the total fineness of the lyocell material may be in a range of 1,667 tex to 6,111 tex (15,000 denier to 55,000 denier), and the total fineness of the lyocell material may be calculated as the sum of the finenesses of the lyocell monofilaments. For example, a lower limit of the total fineness may be, for example, 1,778 tex (16,000 denier) or more, 1,833 tex (16,500 denier) or more, 1,889 tex (17,000 denier) or more, 1,944 tex (17,500 denier) or more, 2,000 tex (18,000 denier) or more, 2,056 tex (18,500 denier) or more, 2,111 tex (19,000 denier) or more, 2,167 tex (19,500 denier) or more, 2,222 tex (20,000 denier) or more, 2,278 tex (20,500 denier) or more, 2,333 tex (21,000 denier) or more, 2,389 tex (21,500 denier) or more, 2,444 tex (22,000 denier) or more, 2,500 tex (22,500 denier) or more, 2,556 tex (23,000 denier) or more, 2,611 tex (23,500 denier) or more, 2,667 tex (24,000 denier) or more, 2,722 tex (24,500 denier) or more, 2,778 tex (25,000 denier) or more, 2,833 tex (25,500 denier) or more, 2,889 tex (26,000 denier) or more, 2,944 tex (26,500 denier) or more, 3,000 tex (27,000 denier) or more, 3,056 tex (27,500 denier) or more, 3,111 tex (28,000 denier) or more, 3,167 tex (28,500 denier) or more, 3,222 tex (29,000 denier) or more, 3,287 tex (29,500 denier) or more, 3,333 tex (30,000 denier) or more, 3,389 tex (30,500 denier) or more, 3,444 tex (31,000 denier) or more, 3,500 tex (31,500 denier) or more, 3,556 tex (32,000 denier) or more, 3,611 tex (32,500 denier) or more, 3,667 tex (33,000 denier) or more, 3,722 tex (33,500 denier) or more, 3,778 tex (34,000 denier) or more, 3,833 tex (34,500 denier) or more, 3,889 tex (35,000 denier) or more, 3,944 tex (35,500 denier) or more, 4,000 tex (36,000 denier) or more, 4,056 tex (36,500 denier) or more, 4,111 tex (37,000 denier) or more, 4,167 tex (37,500 denier) or more, 4,222 tex (38,000 denier) or more, 4,278 tex (38,500 denier) or more, 4,333 tex (39,000 denier) or more, 4,389 tex (39,500 denier) or more, 4,444 tex (40,000 denier) or more, 4,500 tex (40,500 denier) or more, 4,556 tex (41,000 denier) or more, 4,611 tex (41,500 denier) or more, 4,667 tex (42,000 denier) or more, 4,722 tex (42,500 denier) or more, 4,778 tex (43,000 denier) or more, 4,833 tex (43,500 denier) or more, 4,889 tex (44,000 denier) or more, 4,944 tex (44,500 denier) or more, 5,000 tex (45,000 denier) or more, 5,056 tex (45,500 denier) or more, 5,111 tex (46,000 denier) or more, 5,167 tex (46,500 denier) or more, 5,222 tex (47,000 denier) or more, 5,278 tex (47,500 denier) or more, 5,333 tex (48,000 denier) or more, 5,389 tex (48,500 denier) or more, 5,444 tex (49,000 denier) or more, 5,500 tex (49,500 denier) or more, 5,556 tex (50,000 denier) or more, 5,611 tex (50,500 denier) or more, 5,667 tex (51,000 denier) or more, 5,722 tex (51,500 denier) or more, 5,778 tex (52,000 denier) or more, 5,833 tex (52,500 denier) or more, 5,889 tex (53,000 denier) or more, 5,944 tex (53,500 denier) or more, 6,000 tex (54,000 denier) or more, or 6,056 tex (54,500 denier) or more. An upper limit of the total fineness may be, for example, 6,056 tex (54,500 denier) or less, 6,000 tex (54,000 denier) or less, 5,944 tex (53,500 denier) or less, 5,889 tex (53,000 denier) or less, 5,833 tex (52,500 denier) or less, 5,778 tex (52,000 denier) or less, 5,722 tex (51,500 denier) or less, 5,667 tex (51,000 denier) or less, 5,611 tex (50,500 denier) or less, 5,556 tex (50,000 denier) or less, 5,500 tex (49,500 denier) or less, 5,444 tex (49,000 denier) or less, 5,389 tex (48,500 denier) or less, 5,333 tex (48,000 denier) or less, 5,278 tex (47,500 denier) or less, 5,222 tex (47,000 denier) or less, 5,167 tex (46,500 denier) or less, 5,111 tex (46,000 denier) or less, 5,056 tex (45,500 denier) or less, 5,000 tex (45,000 denier) or less, 4,944 tex (44,500 denier) or less, 4,889 tex (44,000 denier) or less, 4,833 tex (43,500 denier) or less, 4,778 tex (43,000 denier) or less, 4,722 tex (42,500 denier) or less, 4,667 tex (42,000 denier) or less, 4,611 tex (41,500 denier) or less, 4,556 tex (41,000 denier) or less, 4,500 tex (40,500 denier) or less, 4,444 tex (40,000 denier) or less, 4,389 tex (39,500 denier) or less, 4,333 tex (39,000 denier) or less, 4,278 tex (38,500 denier) or less, 4,222 tex (38,000 denier) or less, 4,167 tex (37,500 denier) or less, 4,111 tex (37,000 denier) or less, 4,056 tex (36,500 denier) or less, 4,000 tex (36,000 denier) or less, 3,944 tex (35,500 denier) or less, 3,889 tex (35,000 denier) or less, 3,833 tex (34,500 denier) or less, 3,778 tex (34,000 denier) or less, 3,722 tex (33,500 denier) or less, 3,667 tex (33,000 denier) or less, 3,611 tex (32,500 denier) or less, 3,556 tex (32,000 denier) or less, 3,500 tex (31,500 denier) or less, 3,444 tex (31,000 denier) or less, 3,389 tex (30,500 denier) or less, 3,333 tex (30,000 denier) or less, 3,278 tex (29,500 denier) or less, 3,222 tex (29,000 denier) or less, 3,167 tex (28,500 denier) or less, 3,111 tex (28,000 denier) or less, 3,056 tex (27,500 denier) or less, 3,000 tex (27,000 denier) or less, 2,944 tex (26,500 denier) or less, 2,889 tex (26,000 denier) or less, 2,833 tex (25,500 denier) or less, 2,778 tex (25,000 denier) or less, 2,722 tex (24,500 denier) or less, 2,667 tex (24,000 denier) or less, 2,611 tex (23,500 denier) or less, 2,556 tex (23,000 denier) or less, 2,500 tex (22,500 denier) or less, 2,444 tex (22,000 denier) or less, 2,389 tex (21,500 denier) or less, 2,333 tex (21,000 denier) or less, 2,278 tex (20,500 denier) or less, 2,222 tex (20,000 denier) or less, 2,167 tex (19,500 denier) or less, 2,111 tex (19,000 denier) or less, 2,056 tex (18,500 denier) or less, 2,000 tex (18,000 denier) or less, 1,944 tex (17,500 denier) or less, 1,889 tex (17,000 denier) or less, 1,833 tex (16,500 denier) or less, 1,778 tex (16,000 denier) or less, or 1,722 tex (15,500 denier) or less. When the total fineness is out of such a range, the preparation processability of a filter for a smoking article may not be good (continuous process is not possible due to cutting), and when an amount of tow filling filter paper during preparation of a filter for a smoking article may be too small or too large, it may be difficult to secure sufficient filter physical properties (for example, hardness or suction resistance).

[0107] A method of measuring a fineness is not particularly limited, but for example, a lyocell material to be measured, for example, a 2 m sample of lyocell tow, is taken, left, and stabilized in a room with a constant temperature and humidity at a temperature of 20 °C and a humidity of 65 % for 24 hours. One end of the stabilized lyocell tow is fixed, and a 2 kg weight is attached to the other end thereof. The tow stretched due to a load thereof is maintained (stabilized) for 5 seconds and then cut into 90 cm length to obtain a sample and measure a weight of the sample (total fineness). A fineness is converted into a measured weight×10,000 according to a denier conversion method. A single fiber fineness of a monofilament in the sample is calculated by dividing the total fineness of the sample by the number of monofilaments in the sample.

[0108] The total fineness of the lyocell multifilament may be determined according to a single fiber fineness of a filament and the number of crimps. In the present application, a single fiber fineness and the number of crimps may be controlled, and the total fineness of tow suitable for preparing a filter for a smoking article and securing a function thereof may be secured.[Number of crimps]

[0109] In some embodiments, a lyocell multifilament may have 3.94 to 23.62 crimps per centimeter (10 to 60 crimps per inch). The unit "ea / inch (ea / cm)" refers to the number of crimps per unit length (inch or rather cm), wherein the term "ea" refers to the number of crimps. For example, the number of crimps may be 5.91 ea / cm (15 ea / inch) or more, 7.87 ea / cm (20 ea / inch) or more, 9.84 ea / cm (25 ea / inch) or more, 11.81 ea / cm (30 ea / inch) or more, 13.78 ea / cm (35 ea / inch) or more, 15.75 ea / cm (40 ea / inch) or more, or 17.72 ea / cm (45 ea / inch) or more, and an upper limit thereof may be, for example, 21.69 ea / cm (55 ea / inch) or less, 19.69 ea / cm (50 ea / inch) or less, 17.72 ea / cm (45 ea / inch) or less, 15.75 ea / cm (40 ea / inch) or less, 13.78 ea / cm (35 ea / inch) or less, 11.81 ea / cm (30 ea / inch) or less, or 9.84 ea / cm (25 ea / inch) or less. The number of crimps and the uniformity thereof may be controlled under pressure and temperature conditions or the like related to crimping which will be described below.

[0110] Although not particularly limited, the number of crimps may be measured by using, for example, a single fiber property evaluation device (for example, Favimat). Specifically, a sample of a prepared lyocell material (for example, lyocell tow) may be left and stabilized for 24 hours under conditions of a temperature of 20±2 °C and a humidity of 65±4 %. A specimen may be taken from the stabilized sample such that the crimp is not damaged. The taken specimen may be mounted on a dedicated jig with a length (gauge length) of 10 mm to 30 mm. An initial load during measurement may be 0.45 g / tex (0.05 g / denier), and crimp sensitivity may be 0.01 mm. The number of crimps may be measured under the above-described conditions (that is, a temperature of 20±2 °C and a humidity of 65±4 %).

[0111] Although not particularly limited, a lyocell material prepared to satisfy the single fiber fineness, the total fineness, and / or the number of crimps described above may be used in a smoking article.[Binder]

[0112] According to certain embodiments, the lyocell material may further include a binder. The binder may be present, for example, on a surface of the lyocell multifilament or between the lyocell multifilaments (or the monofilaments). The binder may further increase the hardness of a filter for a smoking article, thereby preventing problems such as filter jamming during a process of preparing a filter or a process of preparing a smoking article (for example, a tobacco).

[0113] Types of available binders are not particularly limited, and any known binder may be used at a level that does not impede the purpose of the present disclosure. For example, a binder capable of providing sufficient compatibility with an emulsion used in the present application, improving the hardness of a filter, and providing excellent bonding strength may be used.

[0114] In some embodiments, the binder may include a polyester-based binder, a cellulose-based binder, and / or a vinyl-based binder.

[0115] In some embodiments, as the polyester-based binder, a polyester binder including at least one selected from the group consisting of alkylene, arylene, and heteroarylene having 5 to 12 carbon atoms may be used.

[0116] Examples of the cellulose-based binder may include hydroxypropyl methyl cellulose (HPMC), ethyl cellulose (EC), methyl cellulose (MC), and / or carboxymethyl cellulose (CMC), but one or more embodiments are not limited thereto. According to certain embodiments, the cellulose-based binder is selected from the group consisting of hydroxypropyl methyl cellulose (HPMC), ethyl cellulose (EC), methyl cellulose (MC), carboxymethyl cellulose (CMC), or a combination thereof.

[0117] Examples of the vinyl-based binder may include polyvinylpyrrolidone (PVP), polyvinyl alcohol (PVA), and / or ethylene vinyl acetate (EVAc), but one or more embodiments are not limited thereto. According to certain embodiments, the vinyl-based binder is selected from the group consisting of polyvinylpyrrolidone (PVP), polyvinyl alcohol (PVA), ethylene vinyl acetate (EVAc), or a combination thereof.

[0118] A method of applying the binder onto a lyocell material (coating) will be described below.[Emulsion]

[0119] In some embodiments, the lyocell material may include a lyocell multifilament, and an emulsion applied onto the lyocell multifilament. The emulsion includes: (a) an esterified product of a fatty acid having 16 or more carbon atoms and aliphatic monohydric alcohol; and (b) an esterified product of sorbitan and a fatty acid having 16 or more carbon atoms. The emulsion may be applied onto some or all of monofilaments or multifilaments constituting the lyocell material. In addition, the emulsion may permeate between filaments.

[0120] The emulsion including at least components (a) and (b) may have hydrophobicity. As a result, the lyocell material treated with the emulsion has excellent spreading properties.

[0121] In some embodiments, the lyocell material may include a certain content of the emulsion. In this case, the content of the emulsion may refer to an oil pick up ratio (OPU) (wt%) which will be described below. "OPU" may refer to "oil pick up ratio." In some embodiments, the lyocell material may include the emulsion in a content of 0.1 wt% or more with respect to 100 wt% of the total weight of the lyocell material. For example, the content of the emulsion may be 0.5 wt% or more, 1.0 wt% or more, 1.5 wt% or more, 2.0 wt% or more, 2.5 wt% or more, or 3.0 wt% or more, or specifically 3.5 wt% or more, 4.0 wt% or more, 4.2 wt% or more, 4.5 wt% or more, 5.0 wt% or more, 5.5 wt% or more, 6.0 wt% or more, 6.5 wt% or more, 7.0 wt% or more, 7.5 wt% or more, 8.0 wt% or more, 8.5 wt% or more, 9.0 wt% or more, or 9.5 wt% or more. An upper limit of the content of the emulsion may be, for example, 20.0 wt% or less, 18.0 wt% or less, 17.0 wt% or less, 16.0 wt% or less, 15.0 wt% or less, 14.5 wt% or less, 14.0 wt% or less, 13.5 wt% or less, 13.0 wt% or less, 12.5 wt% or less, 12.0 wt% or less, 11.5 wt% or less, 11.0 wt% or less, 10.5 wt% or less, 10 wt% or less, 9.5 wt% or less, 9.0 wt% or less, 8.5 wt% or less, 8.0 wt% or less, 7.8 wt% or less, or 7.6 wt% or less.

[0122] As a method of measuring the content (OPU) of the emulsion, for example, an extrusion method may be used. For example, a sample (for example, in a content of 2 g to 5 g or specifically about 2.5 g) is collected (in this case, a weight of the collected sample is referred to as a sample weight), and the sample is put into a syringe-shaped container. A material of the container is not particularly limited, but may be a stainless steel (SUS) material. Next, a solvent (for example, methanol) is put into the container into which the sample is put (an amount of the put solvent may be 10 ml or less (for example, about 8 ml)). When the solvent is added to the sample, a dropping method may be used, and a dropping speed may be uniformly adjusted. As described above, the solvent put into the container is allowed to drop on a plate from one end of the syringe-shaped container. In this case, the plate is pre-weighed (a measured weight is referred to as plate weight A), and the plate is installed such that the solvent dropped on the plate is removed away (that is, evaporated) at a temperature of 120 °C to 130 °C (for example, 125 °C). The solvent addition and solvent dropping are performed three times, and pressure (for example, 98 kgf / cm 2< (10 kgf / cm 2< ) or less, 49 N / cm 2< (5 kgf / cm 2< ) or less, or 20 N / cm 2< to 39 N / cm 2< (2 4 kgf / cm 2< to 4 kgf / cm 2< )) is applied to the sample by using a syringe-shaped container to press the sample once. Thus, the solvent and emulsion present in the sample are sufficiently extruded. The sample is squeezed out by applying pressure until the solvent does not come out. Afterwards, the plate is stored in a desiccator for 5 minutes to 10 minutes, and a weight (plate weight B) of the plate containing the sample is measured. Then, a content of the emulsion is calculated according to the following equation.

[0123] In addition, a lyocell material that is used as a reference for the content of the emulsion may be a lyocell multifilament at least treated with an emulsion. For example, the lyocell material may be a lyocell multifilament to which primary emulsion treatment (to be described below) has been applied, a lyocell multifilament to which primary emulsion treatment and secondary emulsion treatment (to be described below) have been applied, or a lyocell multifilament treated with the above-described emulsion and also treated with a binder to be described below. In addition, the lyocell multifilament treated with the emulsion and / or the binder may be imparted with crimps.

[0124] Regarding the emulsion of the present application, component (a) is a compound that may function as a type of lubricant or oil and is a component that may be harmless to the human body enough to be used in food. Component (a) imparts lubricity to fibers put into a crimper. When the lubricity is not sufficient, lyocells clump together and do not escape the crimper, and when the lubricity is too high, there is a problem in that a crimp is not formed properly. In consideration of such functions, a content of component (a) may be controlled as described below.

[0125] Regarding component (a), types of fatty acids having 16 or more carbon atoms forming component (a) are not particularly limited. Fatty acids having 16 or more carbon atoms may be used as long as the fatty acids may provide esterified products that may be harmless to the human body enough to be used in food.

[0126] For example, saturated fatty acids and / or unsaturated fatty acids may be used as fatty acids having one or more 16 carbon atoms.

[0127] Examples of the saturated fatty acids may include a palmitic acid (hexadecanoic acid, CH 3 (CH 2 ) 14 COOH), a margaric acid (heptadecanoic acid, CH 3 (CH 2 ) 15 COOH), a stearic acid (octadecanoic acid, CH 3 (CH 2 ) 16 COOH), a nonadecylic acid (nonadecanoic acid, CH 3 (CH 2 ) 17 COOH), or an arachidic acid (eicosanoic acid, CH 3 (CH 2 ) 18 COOH). However, types of available saturated fatty acids are not limited thereto. According to certain embodiments the saturated fatty acid is selected from the group consisting of palmitic acid (hexadecanoic acid, CH 3 (CH 2 ) 14 COOH), margaric acid (heptadecanoic acid, CH 3 (CH 2 ) 15 COOH), stearic acid (octadecanoic acid, CH 3 (CH 2 ) 16 COOH), nonadecylic acid (nonadecanoic acid, CH 3 (CH 2 ) 17 COOH), arachidic acid (eicosanoic acid, CH 3 (CH 2 ) 18 COOH), or a combination thereof.

[0128] Examples of the unsaturated fatty acids may include a palmitoleic acid (CH 3 (CH 2 ) 5 CH=CH(CH 2 ) 7 COOH), an oleic acid (CH 3 (CH 2 ) 7 CH=CH(CH 2 ) 7 COOH), a linoleic acid (C 18 H 32 O 2 ), or an arachidonic acid (C 20 H 32 O 2 ). According to certain embodiments the unsaturated fatty acid is selected from the group consisting of palmitoleic acid (CH 3 (CH 2 ) 5 CH=CH(CH 2 ) 7 COOH), oleic acid (CH 3 (CH 2 ) 7 CH=CH(CH 2 ) 7 COOH), linoleic acid (C 18 H 32 O 2 ), arachidonic acid (C 20 H 32 O 2 ), or combination thereof.

[0129] However, types of available saturated fatty acids are not limited thereto. According to some embodiments, the fatty acid is selected from the group consisting of a palmitic acid, a margaric acid, a stearic acid, a nonadecylic acid, an arachidic acid, a palmitoleic acid, an oleic acid, a linoleic acid, and an arachidonic acid.

[0130] In some embodiments, an upper limit of a carbon number of the fatty acid having 16 or more carbon atoms is not particularly limited, but may be, for example, 40 or less, 36 or less, 32 or less, 28 or less, 24 or less, or 20 or less.

[0131] Regarding component (a), types of aliphatic monohydric alcohols forming component (a) are also not particularly limited. Aliphatic monohydric alcohols may be used as long as the aliphatic monohydric alcohols may provide esterified products that are harmless to the human body enough to be used in foods.

[0132] In some embodiments, the aliphatic monohydric alcohol may be saturated aliphatic alcohol or unsaturated aliphatic alcohol which may have a linear or branched form.

[0133] In some embodiments, a carbon number of the aliphatic monohydric alcohol may be in a range of 1 to 40. The carbon number of the aliphatic monohydric alcohol may be, for example, 4 or more, 8 or more, 12 or more, 16 or more, or 20 or more.

[0134] Examples of the aliphatic monohydric alcohol may include methanol, ethanol, butanol, lauryl alcohol, isotridecanol, or stearyl alcohol, but one or more embodiments are not limited thereto. According to some embodiments, the aliphatic monohydric alcohol is selected from the group consisting of methanol, ethanol, butanol, lauryl alcohol, isotridecanol, and stearyl alcohol.

[0135] In some embodiments, an esterified product of isotridecanol and a stearic acid (for example, isotridecyl stearate) may be used as component (a). However, types of available component (a) are not limited thereto.

[0136] As will be described below, a content of component (a) included in the emulsion may be adjusted in consideration of the function of the emulsion or the function of component (a).

[0137] Component (b), that is, an esterified product of sorbitan and a fatty acid having 16 or more carbon atoms, may be a compound that may function as a type of emulsifier and may be a component harmless to the human body enough to be used in food.

[0138] Since component (b) has both hydrophilicity and hydrophobicity due to polyhydric alcohol (that is, sorbitan), component (b) enables component (a), which imparts lubricity to fibers, to be well dispersed in water which will be described below. In addition, components (a) and (b) used together not only may increase the dispersibility of the emulsion as described above, but also may lower a melting point, thereby ensuring the use / handling and stability of the emulsion. In consideration of such functions, a content of component (b) may be controlled as described below.

[0139] Regarding component (b), types of fatty acids having 16 or more carbon atoms forming component (b) are not particularly limited. Fatty acids having 16 or more carbon atoms may be used as long as the fatty acids may provide esterified products that may be harmless to the human body enough to be used in food.

[0140] In some embodiments, saturated fatty acids and / or unsaturated fatty acids may be used as fatty acids having one or more 16 carbon atoms.

[0141] Examples of the saturated fatty acids may include a palmitic acid (hexadecanoic acid, CH 3 (CH 2 ) 14 COOH), a margaric acid (heptadecanoic acid, CH 3 (CH 2 ) 15 COOH), a stearic acid (octadecanoic acid, CH 3 (CH 2 ) 16 COOH), a nonadecylic acid (nonadecanoic acid, CH 3 (CH 2 ) 17 COOH), or an arachidic acid (eicosanoic acid, CH 3 (CH 2 ) 18 COOH). According to certain embodiments, the saturated fatty acid is selected from the group consisting of palmitic acid (hexadecanoic acid, CH 3 (CH 2 ) 14 COOH), margaric acid (heptadecanoic acid, CH 3 (CH 2 ) 15 COOH), stearic acid (octadecanoic acid, CH 3 (CH 2 ) 16 COOH), nonadecylic acid (nonadecanoic acid, CH 3 (CH 2 ) 17 COOH), arachidic acid (eicosanoic acid, CH 3 (CH 2 ) 18 COOH), or a combination thereof. However, types of available saturated fatty acids are not limited thereto.

[0142] Examples of the unsaturated fatty acids may include a palmitoleic acid (CH 3 (CH 2 ) 5 CH=CH(CH 2 ) 7 COOH), an oleic acid (CH 3 (CH 2 ) 7 CH=CH(CH 2 ) 7 COOH), a linoleic acid (C 18 H 32 O 2 ), or an arachidonic acid (C 20 H 32 O 2 ). In certain embodiments, the unsaturated fatty acid is selected from the group consisting of palmitoleic acid (CH 3 (CH 2 ) 5 CH=CH(CH 2 ) 7 COOH), oleic acid (CH 3 (CH 2 ) 7 CH=CH(CH 2 ) 7 COOH), linoleic acid (C 18 H 32 O 2 ), arachidonic acid (C 20 H 32 O 2 ), or a combination thereof. However, types of available saturated fatty acids are not limited thereto. According to some embodiments, the fatty acid is selected from the group consisting of a palmitic acid, a margaric acid, a stearic acid, a nonadecylic acid, an arachidic acid, a palmitoleic acid, an oleic acid, a linoleic acid, and an arachidonic acid.

[0143] An upper limit of a carbon number of the fatty acid having 16 or more carbon atoms is not particularly limited, but may be, for example, 40 or less, 36 or less, 32 or less, 28 or less, 24 or less, or 20 or less.

[0144] In some embodiments, an esterified product of sorbitan and an oleic acid (for example, sorbitan monooleate) may be used as component (b). However, types of available component (b) are not limited thereto.

[0145] A content of component (b) may be adjusted in consideration of the function of component (b) and the function of the emulsion as described above.

[0146] In some embodiments, the emulsion may include (b) the esterified product of sorbitan and a fatty acid having 16 or more carbon atoms in a content of 20 parts by weight to 60 parts by weight with respect to 100 parts by weight of (a) the esterified product of a fatty acid having 16 or more carbon atoms and aliphatic monohydric alcohol.

[0147] For example, the emulsion of the present application may include component (b) in a content of 25 parts by weight or more, 30 parts by weight or more, 35 parts by weight or more, 40 parts by weight or more, 45 parts by weight or more, or 50 parts by weight or more with respect to 100 parts by weight of component (a). An upper limit of the content of component (b) with respect to 100 parts by weight of component (a) may be, for example, 55 parts by weight or less, 50 parts by weight or less, 45 parts by weight or less, 40 parts by weight or less, 35 parts by weight or less, 30 parts by weight or less, or 25 parts by weight or less. When such a range of the content is satisfied, a surface of a lyocell multifilament or lyocell tow treated with an emulsion may have hydrophobicity.

[0148] In some embodiments, the emulsion may include (a) the esterified product of a fatty acid having 16 or more carbon atoms and aliphatic monohydric alcohol in a content of 40 wt% to 80 wt% with respect to 100 wt% of the total weight of the emulsion. For example, the content of component (a) may be 45 wt% or more, 50 wt% or more, 55 wt% or more, 60 wt% or more, or 65 wt% or more, 70 wt% or more, or 75 wt% or more with respect to 100 wt% of the total weight of the emulsion. An upper limit of the content of component (a) may be, for example, 75 wt% or less, 70 wt% or less, 65 wt% or less, 60 wt% or less, 55 wt% or less, 50 wt% or less, or 45 wt% or less.

[0149] In some embodiments, the emulsion may include an excess amount of component (a).

[0150] In some embodiments, the emulsion may include (b) the esterified product of sorbitan and a fatty acid having 16 or more carbon atoms in a content of 15 wt% to 55 wt% with respect to 100 wt% of the total weight of the emulsion. Specifically, the content of component (b) may be 20 wt% or more, 25 wt% or more, 30 wt% or more, 35 wt% or more, 40 wt% or more, 45 wt% or more, or 50 wt% or more with respect to 100 wt% of the total weight of the emulsion. An upper limit of the content of component (b) may be, for example, 50 wt% or less, 45 wt% or less, 40 wt% or less, 35 wt% or less, 30 wt% or less, or 25 wt% or less.

[0151] In some embodiments, the emulsion may further include water. A small amount of water may assist in emulsifying.

[0152] A content of water is not particularly limited, but water may be included in the remaining content excluding the total content of components (a) and (b) with respect to 100 wt% of the total weight of the emulsion. The content of water in the emulsion (that is, the remaining content excluding the total content of the remaining components excluding water) may be, for example, 10 wt% or less, 9 wt% or less, 8 wt% or less, 7 wt% or less, 6 wt% or less, 5 wt% or less, 4 wt% or less, 3 wt% or less, 2 wt% or less, or 1 wt% or less. A lower limit of the content of water may be, for example, 0 wt% or more, 0.1 wt% or more, 0.5 wt% or more, or 1 wt% or more.[Method of preparing lyocell material]

[0153] The present application relates to a method of preparing a lyocell material. Through the method, a lyocell material may be prepared and used in a smoking article.

[0154] In some embodiments, the method of preparing a lyocell material includes: lyocell dope spinning; coagulating, and obtaining multifilament; washing; emulsion treatment; and crimp imparting (crimping or rather crimping step). In addition, the method of preparing a lyocell material may further include: binder treatment; and other steps.

[0155] The emulsion treatment may be performed before the crimp imparting, after the crimp imparting, or before and after the crimp imparting.

[0156] Each emulsion treatment may independently be performed, for example, by spraying an emulsion with the above-described composition onto a lyocell multifilament or immersing the lyocell multifilament in the emulsion. The emulsion treatment may be performed such that a content (for example, OPU (wt%)) of an emulsion in the lyocell material satisfies a certain range, as described above.

[0157] The crimp imparting may be performed, for example, by applying steam and / or pressure to the lyocell multifilament.

[0158] The method of preparing a lyocell material according to a specific embodiment of the present application, including the emulsion treatment and the crimp imparting, will be described in more detail below. The method of the present application may be performed by including one or more of operations described below.<Lyocell dope spinning (a)>

[0159] A corresponding step is a step of spinning a lyocell spinning dope including lyocell cellulose (or cellulose pulp) and N-methylmorpholine-N-oxide (NMMO).

[0160] Commercialized cellulose acetate filters are pointed out as the major cause of microplastics. However, since an amine oxide-based solvent used in preparing lyocell fibers is recyclable and biodegradable even when discarded, lyocell materials do not generate any pollutants during a production process thereof. Furthermore, since lyocell tow is biodegraded and removed within a relatively short period of time, lyocell is a more environmentally friendly material than cellulose acetate.

[0161] In some embodiments, a content of cellulose in the spinning dope may be in a range of 5 wt% to 15 wt% with respect to 100 wt% of the total weight of the dope. When the content of cellulose is too low, it is difficult to implement the properties of lyocell fiber, and when the content exceeds such a range, it is difficult to dissolve cellulose in a solvent. In consideration of the difficulties, the content of cellulose in the spinning dope may be, for example, 6 wt% or more, 7 wt% or more, 8 wt% or more, 9 wt% or more, or 10 wt% or more, and an upper limit thereof may be, for example, 14 wt% or less, 13 wt% or less, 12 wt% or less, 11 wt% or less, 10 wt% or less, or 9 wt% or less. The term "cellulose" may refer to "lyocell cellulose."

[0162] In some embodiments, the spinning dope may include an aqueous solution of NMMO. The aqueous solution may include, for example, NMMO in a content of 80 parts by weight to 95 parts by weight and water in a content of 5 parts by weight to 20 parts by weight in consideration of a degree of dissolution of cellulose and a process temperature.

[0163] In some embodiments, the cellulose or cellulose pulp may include alpha-cellulose in a content of 85 wt% to 97 wt% with respect to 100 wt% of the total weight of the cellulose.

[0164] In some embodiments, the cellulose or cellulose pulp may include hemicellulose in a content of 1 wt% to 15 wt% with respect to 100 wt% of the total weight of the cellulose. By adjusting the content of the hemicellulose within such a range, the stable physical properties (for example, hardness or suction resistance implementation) and processability of a lyocell material may be more easily secured.

[0165] In some embodiments, in a specific example of the present application, a degree of polymerization (DPw) of the cellulose may be in a range of 600 to 1,700. The polymerization degree may refer to the number of repeating units and / or monomeric units of the components (cellulose, hemicellulose, etc.) contained in the cellulose pulp. In particular, as used in this application, the term "polymerization degree" may refer to the number of monomeric units and / or repeating units in a macromolecule or polymer or oligomer molecule. The polymerization degree (DPw) may be given by DPw = Mn / M0 wherein Mn is the number-average molecular weight of the macromolecule or polymer or oligomer molecule and M0 is the molecular weight of the monomeric unit.

[0166] In the spinning, a shape of a spinneret for discharging the spinning dope is not particularly limited. For example, a donut-shaped spinneret may be used.

[0167] A nozzle temperature of the spinneret, specifically, a spinning temperature thereof, may be appropriately selected by a person skilled in the art. Considering that the viscosity of the spinning dope may vary according to the spinning temperature, and thus discharging may not be performed smoothly, the spinning temperature may be, for example, in a range of 100 °C to 120 °C or 100 °C to 110 °C.

[0168] In some embodiments, the spinning of the spinning dope may be performed under spinning conditions in which a single fiber fineness of a filament is controlled to be in a range of 1.67 dtex to 8.894 dtex (1.5 denier to 8.0 denier). For example, one or more spinning conditions of a discharge amount and a spinning speed of the spinning dope may be appropriately controlled so that a single fiber fineness of a filament included in a lyocell material may satisfy a range of 1.67 dtex to 8.89 dtex (1.5 denier to 8.0 denier). In this case, a single fiber fineness of a filament refers to a fineness of a single monofilament separated from a multifilament, as described above.

[0169] An upper limit of the single fiber fineness of the filament may be, for example, 8.33 dtex (7.5 denier) or less, 7.78 dtex (7.0 denier) or less, 7.22 dtex (6.5 denier) or less, 6.67 dtex (6.0 denier) or less, 6.11 dtex (5.5 denier) or less, 5.56 dtex (5.0 denier) or less, 5.00 dtex (4.5 denier) or less, 3.89 dtex (3.5 denier) or less, 3.33 dtex (3.0 denier) or less, or 2.78 dtex (2.5 denier) or less. A lower limit of the single fiber fineness may be, for example, 2.22 dtex (2.0 denier) or more, 2.78 dtex (2.5 denier) or more, 3.33 dtex (3.0 denier) or more, 3.89 dtex (3.5 denier) or more, 4.44 dtex (4.0 denier) or more, 5.00 dtex (4.5 denier) or more, 5.56 dtex (5.0 denier) or more, 6.11 dtex (5.5 denier) or more, 6.67 dtex (6.0 denier) or more, 7.22 dtex (6.5 denier) or more, or 7.78 dtex (7.0 denier) or more. Satisfying such a range may be more advantageous in implementing the stable suction resistance of a filter for a smoking article. and securing the processability thereof.

[0170] The spinning dope discharged through the spinneret may undergo coagulation which will be described below.<Coagulating, and obtaining multifilament(b)>

[0171] In a corresponding step, the spun spinning dope may be coagulated, and a lyocell multifilament may be obtained.

[0172] For the coagulation, a method in which the spinning dope comes into contact with air and / or a coagulating solution may be used.

[0173] For example, the coagulation may include: primary coagulation of supplying cooling air to a spun lyocell dope; and secondary coagulation of adding a primarily coagulated spinning dope to a coagulating solution to coagulate the spinning dop.

[0174] According to such a coagulation, the lyocell dope discharged from the spinneret may be primarily coagulated in a space (air gap section) between the spinneret and a coagulation tank. For example, cooling air may be supplied to the air gap section from an air cooling part positioned inside the spinneret in a direction from the inside to the outside of the spinneret. In addition, the primary coagulation may be performed through a known so-called air quenching method or means in the related field.

[0175] For example, an upper limit of a temperature of the cooling air used for the primary coagulation may be, for example, 15 °C or less. For example, the cooling air may be air with a temperature of 14 °C or less, 13 °C or less, 12 °C or less, 11 °C or less, or 10 °C or less. When the above temperature is exceeded, the coagulation of the spinning dope by air is not sufficient, and spinning-related processability is not good.

[0176] A lower limit of the temperature of the cooling air may be determined in consideration of spinning processability and / or cross-sectional uniformity of a filament. For example, when the temperature of the cooling air is less than 4 °C, a surface of the spinneret cools, a surface of the filament becomes non-uniform, and spinning processability also deteriorates. In consideration of this, the cooling air may have, for example a temperature of 5 °C or more, 6 °C or more, 7 °C or more, 8 °C or more, or 9 °C or more.

[0177] A degree by which the cooling air is supplied may be adjusted in consideration of sufficient coagulation, spinning processability, and an influence on the physical properties of the filament. For example, the cooling air may be supplied to the discharged spinning dope at an air flow rate of 70 Nm 3< / h to 400 Nm 3< / h. For example, the air flow rate may be 100 Nm 3< / h or more, 150 Nm 3< / h or more, 200 Nm 3< / h or more, or 250 Nm 3< / h or more, and an upper limit thereof may be, for example, 350 Nm 3< / h or less, 300 Nm 3< / h or less, 250 Nm 3< / h or less, 200 Nm 3< / h or less, or 150 Nm 3< / h or less.

[0178] After the primary coagulation as described above, the cooled spinning dope may be supplied to a coagulation tank or bath containing a coagulating solution (secondary coagulation). For proper coagulation, a temperature of the coagulating solution may be, for example, 30 °C or less or 25 °C or less. The temperature of the coagulating solution may be, for example, 10 °C or more, 15 °C or more, or 20 °C or more. When the above temperature is maintained, a coagulation speed may be appropriately maintained.

[0179] A type of a coagulating solution for the secondary coagulation as described above is not particularly limited. For example, the coagulating solution may include at least one selected from water and NMMO.

[0180] Although not particularly limited, when the coagulating solution includes water and NMMO, with respect to 100 wt% of the total weight of the coagulating solution, a content of water in the coagulating solution may be in a range of 60 wt% to 90 wt%, and a content of NMMO may be in a range of 10 wt% to 40 wt%. Alternatively, the coagulating solution may include water in a content of about 70 wt% to about 80 wt% and NMMO in a content of about 20 wt% to about 30 wt% with respect to 100 wt% of the total weight of the coagulating solution. By using sensors or the like, a concentration of the coagulating solution may be controlled to be maintained during a preparation process.<Washing C>

[0181] If necessary, washing may be performed on a lyocell multifilament after the above-described coagulation and multifilament obtainment. Through such washing, NMMO and / or other impurities remaining in the filament may be removed.

[0182] A method of performing washing is not particularly limited. For example, washing may be performed by introducing a coagulated lyocell multifilament into a washing tank by using a traction roller. Alternatively, washing may be performed by spraying a washing solution while moving to a subsequent operation by a traction roller.

[0183] Components of the washing solution are not particularly limited. For example, the washing solution may include water and may further include known other additives.

[0184] In addition, in consideration of reuse after washing, the washing solution may be used by adjusting a temperature thereof to 100 °C or less.<Emulsion treatment (d)>

[0185] If required, a step of treating the lyocell multifilament with an emulsion may be performed. The step is a step of applying an emulsion with the above-described components onto a surface of the filament. Through emulsion treatment, friction applied to the filament may be reduced, and crimps may be formed well in the crimp imparting which will be described below. When the emulsion treatment is performed twice or more as described below, the emulsion treatment may be referred to as primary emulsion treatment and secondary emulsion treatment according to the order.

[0186] Although not particularly limited, the emulsion treatment may be performed by immersing the lyocell multifilament in a bath filled with an emulsion such that the lyocell multifilament is completely immersed in the emulsion. Alternatively, the emulsion treatment may be performed by spraying the emulsion while moving to a subsequent operation by a traction roller.

[0187] In order to ensure that an amount of the emulsion applied onto the lyocell multifilament is constant after the emulsion treatment as described above, a process in which rolls or the like positioned before and / or after the emulsion treatment squeeze out an emulsion of a surface of the lyocell multifilament may be additionally performed.

[0188] In some embodiments, the emulsion treatment may be performed such that a content (OPU (wt%)) of the emulsion is 1.0 wt% or more with respect to 100 wt% of a lyocell multifilament which has been at least treated with an emulsion. In this case, the lyocell multifilament which has been at least treated with the emulsion, for example, the lyocell material, may be a lyocell multifilament to which primary emulsion treatment has been applied, a lyocell multifilament to which primary emulsion treatment and secondary emulsion treatment (see the description below) have been applied, or a lyocell multifilament to which the emulsion treatment as described above and a binder described below have been applied together. The lyocell multifilament treated with the emulsion and / or the binder as described above may be imparted with crimps.

[0189] For example, in the lyocell multifilament which has been at least treated with the emulsion, a content of the emulsion may be 0.5 wt% or more, 1.0 wt% or more, 1.5 wt% or more, 2.0 wt% or more, 2.5 wt% or more, or 3.0 wt% or more, specifically 3.5 wt% or more, 4.0 wt% or more, 4.2 wt% or more, 4.5 wt% or more, 5.0 wt% or more, 5.5 wt% or more, 6.0 wt% or more, 6.5 wt% or more, 7.0 wt% or more, 7.5 wt% or more, 8.0 wt% or more, 8.5 wt% or more, 9.0 wt% or more, or 9.5 wt% or more with respect to 100 wt% of the total weight of the lyocell multifilament which has been at least treated with the emulsion. An upper limit of the content of the emulsion may be, for example, 20.0 wt% or less, 18.0 wt% or less, 17.0 wt% or less, 16.0 wt% or less, 15.0 wt% or less, 14.5 wt% or less, 14.0 wt% or less, 13.5 wt% or less, 13.0 wt% or less, 12.5 wt% or less, 12.0 wt% or less, 11.5 wt% or less, 11.0 wt% or less, 10.5 wt% or less, 10 wt% or less, 9.5 wt% or less, 9.0 wt% or less, 8.5 wt% or less, 8.0 wt% or less, 7.8 wt%, or 7.6 wt% or less with respect to 100 wt% of the total weight of the lyocell multifilament which has been at least treated with the emulsion. In this case, the above content may refer to a dry weight after a solvent (for example, water) or liquid component that may be included in the emulsion has evaporated.

[0190] When the lyocell multifilament is treated with the emulsion with the above-described composition within such a range of the content, the hydrophilic properties of the lyocell material may be supplemented.

[0191] In some embodiments, the emulsion may be dried after the emulsion treatment as described above.

[0192] In some embodiments, one or more of the above-described operations may be controlled such that a single fiber fineness of a filament constituting the lyocell multifilament may be in a range of 1.67 to 8.89 dtex (1.5 denier to 8.0 denier). The single fiber fineness of the filament refers to a fineness of a single monofilament separated from a multifilament, as described above.

[0193] In some embodiments, one or more of the above-described operations may be controlled such that the single fiber fineness of the filament constituting the lyocell multifilament may be in a range of 1.67 dtex to 8.89 dtex (1.5 denier to 8.0 denier). The single fiber fineness of the filament refers to a fineness of a single monofilament separated from a multifilament, as described above.

[0194] An upper limit of the single fiber fineness of the filament may be, for example, 8.33 dtex (7.5 denier) or less, 7.78 dtex (7.0 denier) or less, 7.22 dtex (6.5 denier) or less, 6.67 dtex (6.0 denier) or less, 6.11 dtex (5.5 denier) or less, 5.56 dtex (5.0 denier) or less, 5.00 dtex (4.5 denier) or less, 3.89 dtex (3.5 denier) or less, 3.33 dtex (3.0 denier) or less, or 2.78 dtex (2.5 denier) or less. A lower limit of the single fiber fineness may be 2.22 dtex (2.0 denier) or more, 2.78 dtex (2.5 denier) or more, 3.33 dtex (3.0 denier) or more, 3.89 dtex (3.5 denier) or more, 4.44 dtex (4.0 denier) or more, 5.00 dtex (4.5 denier) or more, 5.56 dtex (5.0 denier) or more, 6.11 dtex (5.5 denier) or more, 6.67 dtex (6.0 denier) or more, 7.22 dtex (6.5 denier) or more, or 7.78 dtex (7.0 denier) or more. Satisfying such a range may be more advantageous in implementing the stable suction resistance of a filter for a smoking article and securing the processability thereof.

[0195] Although not particularly limited, a step controlled to secure such a range of the single fiber fineness may be the above-described spinning. Alternatively, the above-described spinning, coagulation, washing, and emulsion treatment may all be controlled to secure such a range of the single fiber fineness.<Crimp imparting (e)>

[0196] The crimp imparting is a step of applying pressure to the lyocell multifilament treated with the emulsion through steam and / or a press roller to obtain a crimped multifilament, for example, crimped tow. The crimp imparting may be referred to as crimping.

[0197] Through crimping, waves may be imparted to the lyocell multifilament, and fibers may have bulky properties. According to certain embodiments, the crimping may be performed by using a known crimp machine including a stuffer box and / or a steam box, and available crimp machines are not particularly limited as long as the crimp machines are devices capable of applying one or more of pressures which will be described below.

[0198] In some embodiments, a moisture content of the lyocell material measured before the crimp imparting may be in a range of 150 % to 400 %.

[0199] For example, the crimp imparting may be performed by first supplying steam to the lyocell multifilament to preheat and swell the lyocell multifilament, and then pressing the lyocell multifilament with a press roller to form wrinkles in the lyocell multifilament. In this case, the steam box may be used to supply steam and may be positioned in front of the crimp machine.

[0200] For example, the crimp imparting may be performed in such a manner that pressing of the lyocell multifilament by the press roller and applying of steam are simultaneously performed.

[0201] For example, the crimp imparting may be performed in such a manner that steam is first supplied to the lyocell multifilament to preheat and swell the lyocell multifilament, and then pressing of the lyocell multifilament by the press roller and applying of steam are simultaneously performed.

[0202] For example, the crimp imparting may be performed by applying steam with a pressure of about 0.98 N / cm 2< to about 19.61 N / cm 2< (about 0.1 kgf / cm 2< to 2.0 kgf / cm 2< ) to each lyocell multifilament before the lyocell multifilament is input into the crimp machine (specifically, the press roller).

[0203] For example, steam with a pressure of 1.96 N / cm 2< (0.2 kgf / cm 2< ) or more, 2.94 N / cm 2< (0.3 kgf / cm 2< ) or more, 3.92 N / cm 2< (0.4 kgf / cm 2< ) or more, 4.90 N / cm 2< (0.5 kgf / cm 2< ) or more, or 5.88 N / cm 2< (0.6 kgf / cm 2< ) or more may be supplied by the steam box. In addition, steam with a pressure of 14.71 N / cm2 (1.5 kgf / cm2) or less, 13.73 N / cm2 (1.4 kgf / cm2) or less, 12.75 N / cm2 (1.3 kgf / cm2) or less, 11.77 N / cm2 (1.2 kgf / cm2) or less, 10.79 N / cm2 (1.1 kgf / cm2) or less, or 9.81 N / cm2 (1.0 kgf / cm2) or less may be supplied. When an amount or pressure of supplied steam is less than such a range, crimps may not be formed smoothly. When such a range is exceeded, since the flexibility of a filament is increased, excessive crimps may be imparted to the filament in the crimp machine, and thus the filament may not pass through the crimp machine.

[0204] For example, the crimp imparting may be performed by pressing the lyocell multifilament with the press roller to form wrinkles in the lyocell multifilament. In addition, steam may not be supplied before pressing, steam may not be supplied simultaneously with pressing, or steam may not be supplied before pressing and simultaneously with pressing.

[0205] For example, the crimp imparting may be performed by each independently applying pressures of 14.71 N / cm 2< to 39.23 N / cm 2< (1.5 kgf / cm 2< to 4.0 kgf / cm 2< ) to each lyocell multifilament put into the crimp machine by using the press roller.

[0206] For example, a pressure of 15.69 N / cm 2< (1.6 kgf / cm 2< ) or more, 16.67 N / cm 2< (1.7 kgf / cm 2< ) or more, 17.65 N / cm 2< (1.8 kgf / cm 2< ) or more, 18.63 N / cm 2< (1.9 kgf / cm 2< ) or more, 19.61 N / cm 2< (2.0 kgf / cm 2< ) or more, 20.60 N / cm 2< (2.1 kgf / cm 2< ) or more, 21.58 N / cm 2< (2.2 kgf / cm 2< ) or more, 22.56 N / cm 2< (2.3 kgf / cm 2< ) or more, 23.54 N / cm 2< (2.4 kgf / cm 2< ) or more, or 24.52 N / cm 2< (2.5 kgf / cm 2< ) or more may be applied to the lyocell multifilament through the press roller. In addition, a pressure of 38.25 N / cm 2< (3.9 kgf / cm 2< ) or less, 37.27 N / cm 2< (3.8 kgf / cm 2< ) or less, 36.29 N / cm 2< (3.7 kgf / cm 2< ) or less, 35.31 N / cm 2< (3.6 kgf / cm 2< ) or less, 34.33 N / cm 2< (3.5 kgf / cm 2< ) or less, 33.35 N / cm 2< (3.4 kgf / cm 2< ) or less, 32.37 N / cm 2< (3.3 kgf / cm 2< ) or less, 31.39 N / cm 2< (3.2 kgf / cm 2< ) or less, 30.41 N / cm 2< (3.1 kgf / cm 2< ) or less, 29.42 N / cm 2< (3.0 kgf / cm 2< ) or less, 28.44 N / cm 2< (2.9 kgf / cm 2< ) or less, 27.46 N / cm 2< (2.8 kgf / cm 2< ) or less, 26.48 N / cm 2< (2.7 kgf / cm 2< ) or less, 25.50 N / cm 2< (2.6 kgf / cm 2< ) or less, or 24.52 N / cm 2< (2.5 kgf / cm 2< ) or less may be applied through the press roller.

[0207] When the pressure of the press roller is less than such a range, the desired number of crimps may not be formed sufficiently. When roller pressure exceeds such a range, a pressing force may be too strong, and thus the filament may not be smoothly put into the crimp machine or may not pass through the stuffer box. Wrinkles may be formed in the lyocell multifilament by the press roller that provides the pressure.

[0208] For example, by using an upper plate, pressures of 0.98 N / cm 2< to 19.61 N / cm 2< (0.1 kgf / cm 2< to 2 kgf / cm 2< ) may each independently be applied to each lyocell multifilament. In addition, the upper plate may apply pressure to each lyocell multifilament when each lyocell multifilament has passed through the press roller or while each lyocell multifilament is passing through the press roller.

[0209] For example, the pressure applied by the upper plate may be 1.96 N / cm 2< (0.2 kgf / cm 2< ) or more, 2.94 N / cm 2< (0.3 kgf / cm 2< ) or more, 3.92 N / cm 2< (0.4 kgf / cm 2< ) or more, or 4.90 N / cm 2< (0.5 kgf / cm 2< ) or more. In addition, a pressure of 14.71 N / cm 2< (1.5 kgf / cm 2< ) or less, 13.73 N / cm 2< (1.4 kgf / cm 2< ) or less, 12.75 N / cm 2< (1.3 kgf / cm 2< ) or less, 11.77 N / cm 2< (1.2 kgf / cm 2< ) or less, 10.79 N / cm 2< (1.1 kgf / cm 2< ) or less, or 9.81 N / cm 2< (1.0 kgf / cm 2< ) or less may be applied by the upper plate.

[0210] Furthermore, when the pressure of the upper plate, which vertically moves to provide uniform crimps after each lyocell multifilament passes through the press roller, is less than 0.98 N / cm 2< (0.1 kgf / cm 2< ), since the upper plate may not be fixed due to a pressure inside the stuffer box, while tow remains inside the stuffer box for a long time, the continuity of a process may not be maintained. When the pressure of the upper plate exceeds 19.61 N / cm 2 (< 2 kgf / cm 2< ), since steam inside the stuffer box may not be smoothly discharged, a shape of a crimp may be irregular.

[0211] For example, in the crimp imparting, a doctor blade that applies certain pressure to the lyocell multifilament may be applied. The doctor blade may adjust a residence time of a filament put into a crimper stuffer box, thereby contributing to the adjustment of the number of crimps. The doctor blade may be positioned, for example, on a movement path of the lyocell multifilament that is pressed by the above-described press roller and then discharged from a roller pressing point.

[0212] For example, the crimp imparting may be performed by each independently applying pressures of 0.98 N / cm 2< to 19.61 N / cm 2< (0.1 kgf / cm 2< to 2.0 kgf / cm 2< ) to each lyocell multifilament, which has passed a roller of the crimp machine, by using the doctor blade.

[0213] For example, the pressure applied by the doctor blade may be 1.96 N / cm 2< (0.2 kgf / cm 2< ) or more, 2.94 N / cm 2< (0.3 kgf / cm 2< ) or more, 3.92 N / cm 2< (0.4 kgf / cm 2< ) or more, or 4.90 N / cm 2< (0.5 kgf / cm 2< ) or more. In addition, a pressure of 14.71 N / cm 2< (1.5 kgf / cm 2< ) or less, 13.73 N / cm 2< (1.4 kgf / cm 2< ) or less, 12.75 N / cm 2< (1.3 kgf / cm 2< ) or less, 11.77 N / cm 2< (1.2 kgf / cm 2< ) or less, 10.79 N / cm 2< (1.1 kgf / cm 2< ) or less, or 9.81 N / cm 2< (1.0 kgf / cm 2< ) or less may be applied by the doctor blade.

[0214] For example, the crimp imparting may be performed at a temperature ranging from 120 °C to 250 °C. When the temperature is too low, the effect of stabilizing a shape of crimps may not be good, and when the temperature is too high, a concentration of fat and oil inside the stuffer box may be increased, which may make it difficult to form crimps. Therefore, in consideration of the above-described pressure of the steam or the like, a temperature, for example, may be appropriately controlled in a range of 130 °C or more, 140 °C or more, or 150°C or more, and 200 °C or less, 180 °C or less, or 160 °C or less.<Binder treatment (f)>

[0215] In an example, the method may further include a step of treating, with a binder, the lyocell multifilament treated with the emulsion, or treating, with a binder, the lyocell multifilament obtained through the crimp imparting.

[0216] When a filter for a smoking article is prepared by using the lyocell material (for example, lyocell tow), a binder may be additionally used. The binder may increase the hardness of a filter for a smoking article including a lyocell material, thereby preventing problems such as filter jamming during a process of preparing a filter or a process of preparing a tobacco.

[0217] The treatment of the lyocell material with the binder is not particularly limited. For example, binder treatment may be performed by immersing the lyocell multifilament in a bath filled with a binder (or a binder solution) such that the lyocell multifilament is completely immersed in the binder. Alternatively, binder coating may be performed by spraying (or injecting) the binder (or the binder solution) through a nozzle.

[0218] Types and components of available binders are as described above, and thus descriptions thereof are omitted.

[0219] For example, the binder (or the binder solution) may further include a solvent in addition to the components described above. Examples of the solvent may include water, ethanol, propylene glycol, and / or glycerin, but one or more embodiments are not limited thereto. In some embodiments, the solvent is selected from the group consisting of water, ethanol, propylene glycol, glycerin, or a combination thereof. When the binder (or the binder solution) includes a solvent, a content of the solvent may be, for example, in a range of about 20 to about 80 wt% or about 40 wt% to about 60 wt% with respect to 100 wt% of the total weight of the binder (or the binder solution).

[0220] Such binder treatment may be performed at a level that may achieve the purpose of the above-described binder treatment. For example, the binder treatment may be performed such that a content of the binder satisfies 20 wt% or less, for example, a range of 8 wt% to 15 wt%, with respect to 100 wt% of a lyocell multifilament treated with an emulsion and a binder. In this case, the above content may refer to a dry weight after a solvent or liquid component that may be included in the binder has evaporated.

[0221] After the binder is applied onto the lyocell multifilament, drying of the binder may be performed. A drying temperature is not particularly limited, but, for example, drying may be performed at room temperature (about 10 °C to about 35 °C).<Stacking and pressing (g)>

[0222] After the crimp imparting, an operation of stacking and pressing the lyocell material may be further performed. Through the stacking and pressing, the lyocell material may be stacked and pressed in a certain container. For example, the container may be a hexahedral box and may be filled with the lyocell material through the stacking and pressing.

[0223] In addition, an FPI measured from the lyocell material after the stacking and pressing may be in a range of 19 to 88. Preferably, the FPI measured from the lyocell material after the stacking and pressing may be in a range of 24 to 75.

[0224] In addition, in order for the FPI to satisfy a range of 19 to 88, the stacking and pressing may be performed such that density A (that is, an apparent density) in Equation 2 is in a range of 0.300 g / cm 3< to 1.200 g / cm 3< .

[0225] In some embodiments, more specifically, an upper limit of density A implemented in the stacking and pressing may be 1.150 g / cm 3< or less, 1.100 g / cm 3< or less, 1.050 g / cm 3< or less, 1.000 g / cm 3< or less, 0.950 g / cm 3< or less, 0.900 g / cm 3< or less, 0.850 g / cm 3< or less, 0.800 g / cm 3< or less, 0.750 g / cm 3< or less, 0.700 g / cm 3< or less, or 0.650 g / cm 3< or less. In addition, a lower limit of density A implemented in the stacking and pressing may be, for example, 0.350 g / cm 3< or more, 0.400 g / cm 3< or more, 0.450 g / cm 3< or more, 0.500 g / cm 3< or more, 0.550 g / cm 3< or more, 0.600 g / cm 3< or more, 0.650 g / cm 3< or more, 0.700 g / cm 3< or more, 0.750 g / cm 3< or more, 0.800 g / cm 3< or more, or 0.850 g / cm 3< or more. Preferably, density A implemented in the stacking and pressing may be in a range of 0.500 g / cm 3< to 0.900 g / cm 3< .

[0226] In some embodiments, a pressing pressure of the stacking and pressing may be in a range of 196 N / cm 2< to 588 N / cm 2< (20 kgf / cm 2< to 60 kgf / cm 2< ). When the pressing pressure satisfies such a numerical range, the post-processing properties of the lyocell material such as unwinding properties may be improved.

[0227] When the pressing pressure is less than 196 N / cm 2< (20 kgf / cm 2< ), density A may be excessively low, and Po may exceed 80. As a result, the clumping of the lyocell material may be a problem. When the pressing pressure exceeds 588 N / cm 2< (60 kgf / cm 2< ), density A may be excessively high, and Po may be less than 20. As a result, the cutting of lyocell material may be a problem.

[0228] In addition, the stacking and pressing may be performed such that Po in Equation 1 may be in a range of 15 % to 83 %. For example, Po may be adjusted by performing the stacking and pressing such that density A is in a range of 0.300 g / cm 3< and 1.200 g / cm 3< .<Other steps (h)>

[0229] After the crimp imparting, appropriate post-treatment may be additionally performed.

[0230] In an example, secondary emulsion treatment (h1) may be additionally performed. Through the secondary emulsion treatment, flexibility may be further imparted to tow. The secondary emulsion treatment may be performed in the same manner as or in accordance with the emulsion treatment (d) described above.

[0231] Specifically, the secondary emulsion treatment may be performed by treating, with an emulsion, a lyocell material which has undergone a process using a crimper. The secondary emulsion treatment may function advantageously in various processes performed during the preparation of a filter for a smoking article. For example, the secondary emulsion treatment may allow fibers and filters to spread well even in air during a spreading process and also may restrict fibers from being cut during a stretching process.

[0232] In some embodiments, the secondary emulsion treatment as described above may be performed before or after the binder treatment. Alternatively, the secondary emulsion treatment may be performed irrespective of whether the binder treatment is performed.

[0233] Even in a case in which the secondary emulsion treatment as described above is performed, a secondary emulsion treatment step may be performed such that a content or an OPU content of an emulsion in a material satisfies the range described above.

[0234] For example, drying treatment (h2) may be additionally performed. Such drying may be performed, for example, at a temperature ranging from 100 °C to 130 °C. A drying treatment manner or method is not particularly limited, and known technologies may be used. For example, the drying may be performed by applying hot air to a lyocell material or allowing a lyocell material to pass through a temperature-controlled room or leaving the lyocell material for a certain period of time.

[0235] In an aspect, the present disclosure provides a lyocell material obtained through the method of preparing a lyocell material as described above.

[0236] In an aspect, the present disclosure provides a lyocell material obtainable through the method of preparing a lyocell material as described above.[Smoking article]

[0237] Although not particularly limited, a lyocell material prepared through the method may be included in a smoking article. The smoking article may be an aerosol-generating article. The aerosol-generating article may include an aerosol-generating material or an aerosol-forming substrate.

[0238] For example, the lyocell material may be included in a combustion-type cigarette. Further, the lyocell material may be, for example, included in a heated cigarette, and the heated cigarette may be used together with an aerosol generating device (not shown).

[0239] For example, when used as a heated smoking article, the smoking article may be separately inserted into the aerosol generating device. Here, the aerosol generating device may include an accommodation groove in which an aerosol-generating article may be accommodated, and in addition, may include a heater for heating the aerosol-generating article to generate aerosol, a control unit for controlling the overall operation of the aerosol generating device, a battery for providing power used for operating the aerosol generating device, and a detector for recognizing that the aerosol-generating article has been inserted into the aerosol generating device.

[0240] The smoking article may include a tobacco medium portion, a filter for a smoking article, and a wrapper, wherein the filter for a smoking article may be positioned at one end portion of the tobacco medium portion, for example, a rear end portion or a front end portion. The tobacco medium portion and the filter for a smoking article may each include a single segment or may each independently include a plurality of segments.

[0241] The tobacco medium portion includes a tobacco material, and the tobacco material includes nicotine. In addition, the tobacco medium portion may additionally include excipients.

[0242] The excipients may include a binder, a filler, and other additives. For example, a tobacco medium included in the tobacco medium portion may be prepared in the form of granules including a tobacco material, an excipient, and the like.

[0243] For example, a filler may be additionally included to constantly maintain the shape, strength, and mass of the tobacco medium portion. For example, the lyocell material may be included in the tobacco medium portion. In addition, the lyocell material may be used as a filler.

[0244] The wrapper may be subdivided into cigarette paper for wrapping the tobacco medium portion, filter wrapping paper for wrapping the filter, and a tipping wrapper for coupling the tobacco medium portion and the filter.[Filter for smoking article]

[0245] A lyocell material may be used in a filter for a smoking article. The lyocell material may be lyocell tow. In an example, the lyocell tow includes lyocell multifilaments to which crimps have been imparted.

[0246] According to an aspect, the present application relates to a filter for a smoking article. The filter for a smoking article may include a lyocell material, and the lyocell material may be identical to that described above. In addition, the filter for a smoking article may include lyocell tow, and the lyocell tow may be identical to that described above.

[0247] In addition, the lyocell material may include an emulsion in a content of 0.1 wt% or more with respect to 100 wt% of the total weight of the lyocell material. In addition, an emulsion component and a content according to a specific example of the present application are as described above.

[0248] For example, a single fiber fineness of a filament constituting the lyocell multifilament may be in a range of 1.5 denier to 8.0 denier. A specific numerical value is as described above.

[0249] For example, the lyocell multifilament to which crimps have been imparted may be a lyocell material having a total fineness of 15,000 denier to 55,000 denier, and preferably, the lyocell multifilament may be lyocell tow. A specific numerical value is as described above.

[0250] In an example, the lyocell multifilament to which crimps have been imparted may have 3.94 to 19.69 crimps per cm (10 to 50 crimps per inch). A specific numerical value is as described above.

[0251] For example, the filter for a smoking article may further include a binder on a surface of the lyocell multifilament to which crimps have been imparted or between the lyocell multifilaments to which crimps have been imparted. The binder increases the hardness of a filter for a smoking article prepared from tow, thereby preventing problems such as filter jamming during a process of preparing a filter or a process of preparing a tobacco. Types, components, and contents of available binders are as described above.

[0252] For example, the filter for a smoking article may further include wrapping paper (which may be referred to as wrapper paper, filter paper, or filter wrapping paper). For example, the wrapping paper may be porous paper or non-porous paper that may wrap the above-described lyocell tow and may maintain a filter shape (for example, a cylinder or circular column).

[0253] In some embodiments of the present application, the filter for a smoking article may have a certain shape and a certain size.

[0254] For example, the filter may have a rod shape. For example, the filter for a smoking article may have a shape such as a cylinder.

[0255] In addition, the filter may have a length of, for example, 10 nm to 50 mm. For example, the length of the filter may have a lower limit of 15 mm or more, 20 mm or more, 25 mm or more, 30 mm or more, 35 mm or more, 40 mm or more, or 45 mm or more, and an upper limit of 45 mm or less, 40 mm or less, 35 mm or less, 30 mm or less, 25 mm or less, 20 mm or less, or 15 mm or less.

[0256] In some embodiments of the present application, the filter having the length may have a circular cross section, and a circumference of the circular cross section may be in a range of 10 nm to 40 mm. For example, the circumference of the filter may have a lower limit of 15 mm or more, 20 mm or more, 25 mm or more, 30 mm or more, or 35 mm or more, and an upper limit of 35 mm or less, 30 mm or less, 25 mm or less, 20 mm or less, or 15 mm or less.

[0257] For example, the filter for a smoking article may include lyocell tow and filter wrapping paper. The lyocell tow and the filter wrapping paper are as described above, and thus descriptions thereof are omitted.

[0258] The wrapping paper may be porous paper or non-porous paper that may wrap the above-described lyocell tow and may maintain a filter shape (for example, a cylinder or circular column).

[0259] For example, when porous wrapping paper is used, the wrapping paper may have a porosity of 10 coresta unit (CU) to 50,000 CU. A coresta unit may be defined as a volume flow rate (cm 3< min -1< ) of air passing through a 1 cm 2< substrate sample (that is, porous wrapping paper) at a pressure difference of 1 kPa. A lower limit of the porosity of the wrapping paper may be, for example, 1,000 CU or more, 5,000 CU or more, 10,000 CU or more, 15,000 CU or more, 20,.000 CU or more, 25,000 CU or more, 30,000 CU or more, 35,000 CU or more, 40,000 CU or more, or 45,000 CU or more, and an upper limit thereof may be, for example, 45,000 CU or less, 40,000 CU or less, 35,000 CU or less, 30,000 CU or less, 25,000 CU or less, or 20,000 CU or less. In some embodiments of the present application, the wrapping paper may have a porosity in a range of 22,000 CU to 26,000 CU or 23,000 CU to 25,000 CU.

[0260] For example, a basis weight of the wrapping paper may be in a range of 15 g / m 2< to 60 g / m 2< . A lower limit of the basis weight of the wrapping paper may be, for example, 20 g / m 2< or more, 25 g / m 2< or more, 30 g / m 2< or more, 35 g / m 2< or more, 40 g / m 2< or more, 45 g / m 2< or more, 50 g / m 2< or more, or 55 g / m 2< or more, and an upper limit thereof may be, for example, 55 g / m 2< or less, 50 g / m 2< or less, 45 g / m 2< or less, 40 g / m 2< or less, 35 g / m 2< or less, 30 g / m 2< or less, 25 g / m 2< or less, or 20 g / m 2< or less. In some embodiments of the present application, the wrapping paper may have a basis weight of 16 g / m 2< or more, 17 g / m 2< or more, 18 g / m 2< or more, 19 g / m 2< or more, 20 g / m 2< or more, or 21 g / m 2< or more, and 25 g / m 2< or less, 24 g / m 2< or less, 23 g / m 2< or less, 22 g / m 2< or less, or 21 g / m 2< or less.

[0261] Although not particularly limited, a weight of a filter having a rod shape may be 50 mg or more. The weight of the filter may have, for example, a lower limit of 100 mg or more, 150 mg or more, or 200 mg or more, and an upper limit of 500 mg or less, 450 mg or less, 400 mg or less, 350 mg or less, 300 mg or less, 250 mg or less, or 200 mg or less.

[0262] Other filters for a smoking article and materials included therein are as described above, and thus descriptions thereof are omitted.[Method of preparing filter for smoking article]

[0263] For example, the present application relates to a method of preparing a filter for a smoking article. The method may be a method of preparing a filter for a lyocell smoking article as described above and may be a method including the above-described method of preparing a lyocell material.

[0264] Regarding the method of preparing a filter for a smoking article, the remaining steps excluding preparing of a filter are the same as steps described in the lyocell material described above, and thus descriptions thereof are omitted. In addition, descriptions overlapping the above descriptions are also omitted.

[0265] The preparing of the filter may be appropriately performed by a person skilled in the art according to a known method. For example, the filter may be prepared by forming wrapping paper filled with a lyocell material into a rod shape. Alternatively, the filter may be prepared by cutting, into an appropriate length, filter paper which has a rod shape and is filled with a lyocell material. The wrapping paper is as described above.

[0266] Although not particularly limited, before the filter paper is filled with the lyocell material, the lyocell material may be further subjected to opening or plasticizer treatment. A surface area of the lyocell material may be increased by opening the lyocell material. For example, the lyocell material may be opened by applying an external force in a longitudinal direction, a width direction, and / or a thickness direction.

[0267] Preferably, the lyocell material used in preparing a filter for a smoking article may be lyocell tow.

[0268] Although not particularly limited, the filter for a smoking article may additionally include known cellulose acetate multifilaments at a level that does not impede the purpose of the present disclosure. The cellulose acetate multifilament may be mixed with a lyocell multifilament. The cellulose acetate multifilament may be included in a segment distinguished from a segment including the lyocell multifilament.Advantageous Effects of Invention

[0269] According to the present application, provided are a lyocell material for a filter for a smoking article, which is capable of replacing commercialized cellulose acetate (CA), and a filter for a smoking article including the same. Specifically, by satisfying a certain FPI, the post-processing properties of a lyocell material, for example, unwinding properties, may be improved. As a result, process costs consumed to prepare a filter for a smoking article may be reduced.Mode for the Invention

[0270] Hereinafter, the operations and effects of the present disclosure will be described in more detail through specific examples of the present disclosure. However, this is presented as an example of the present disclosure, and the scope of the present disclosure is not limited thereby.

[0271] A lyocell material was prepared through processes as described in Preparation Example below. Conditions not specifically described are within the scope of the above description.[Preparation Example]

[0272] Cellulose pulp having an alpha-cellulose content of 93.9 % and a DPw of 820 was mixed with an NMMO / H 2 O solvent having a propyl gallate content of 0.01 wt% to prepare a spinning dope for preparing tow having a concentration of 11 wt%. While a spinning temperature of a spinning nozzle was maintained at 110 °C, a discharge amount and a spinning speed were appropriately adjusted, and the spinning dope was spun.

[0273] The spinning dope with a filament phase discharged from the spinning nozzle was supplied to a coagulating solution (a coagulating solution having a concentration of 75 wt% water and 25 wt% NMMO and a temperature of about 25 °C) in a coagulation tank through an air gap section. In this case, cooling air in the air gap section primarily solidifies the spinning dope at a temperature of 8 °C and an air flow rate of 120 Nm 3< / h. In addition, the concentration of the coagulating solution was continuously monitored by using a sensor and a refractometer.

[0274] A coagulated lyocell filament was washed. Specifically, the filament was introduced between traction rollers, and NMMO remaining in the filament was removed by using a washing solution sprayed from a washing device. Then, the washed filament was immersed inside a bath designed to have a certain emulsion concentration. Afterwards, the filament was prepared to satisfy a moisture content of 150 % to 400 %.

[0275] The filament was treated at a pressure of 19.6 N / cm 2< (2 kgf / cm 2< ) through a nip roll installed in a bath discharge portion and put into a crimp machine to impart wrinkles. Specifically, pressure of a press roller was set to 24.52 N / cm 2< (2.5 kgf / cm 2< ), and pressure of a doctor blade was set to 4.90 N / cm 2< (0.5 kgf / cm 2< ) to impart crimps to lyocell materials.

[0276] The lyocell materials to which crimps have been imparted were sequentially stacked in box-shaped containers, and each container was pressed at a pressure of 196 N / cm 2< to 588 N / cm 2< (20 kgf / cm 2< to 60 kgf / cm 2< ).

[0277] Prepared lyocell tow has a single fiber fineness of 2.22 dtex to 8.88 dtex (2.0 denier to 8.0 denier), a total fineness of 3,333 tex to 6,110 tex (30,000 denier to 55,000 denier), and the number of crimps of 5.91 ea / cm to 18.05 ea / cm (15 ea / inch to 55 ea / inch).Examples 1 to 6

[0278] Lyocell materials were prepared according to Preparation Example, and values of a moisture content, pressing pressure, crimp energy CrE, porosity Po, density A, and density B of a filament were as shown in Table 1 below.Comparative Examples 1 to 5

[0279] Lyocell materials were prepared according to Preparation Example and values of a moisture content, pressing pressure, crimp energy CrE, porosity Po, density A, and density B of a filament were as shown in Table 1 below.

[0280] The value of crimp energy of each of Examples and Comparative Examples was measured by using a UTM (Model No. 5566 manufactured by Intron Ltd.,). In order to measure the value of crimp energy, a sample with a length of about 20 was taken from each lyocell material. Each taken sample was mounted on a dedicated jig and weighted to have an initial load of 0.98 N (100 gf). Each sample was weighted until crimps were not identified. The value of crimp energy was calculated by converting a weight weighted when crimps were not identified.

[0281] Meanwhile, the porosity of each of Examples and Comparative Examples was obtained by measuring an apparent density (density A) and a true density (density B) and performing a calculation according to Equation 2 below. 1 − density A / density B × 100

[0282] Density A was obtained by dividing a weight (g) of each of Examples and Comparative Examples by a volume (cm 3< ) of a container containing each of Example and Comparative Example. Density B was measured by using a true specific density meter (model number: AccuPyc II 1340 manufactured by Micromeritics). Gas for analysis was He(g), an equilibrium velocity was about 0.005 psig / min, an expansion volume was about 9.2169 cm 3< , and a cell volume was about 0.0029 g / cm 3< . [Table 1]TargetMoisture content (%)Pressing pressure(N / cm 2< )CrE (mJ)Po (%)Density A (g / cm 3< )Density B (g / cm 3< )Examples120627478265.10.5181.484622882941,46565.20.5131.47303231333.296156.90.6351.47374335352.81,62256.80.6401.48245175431.258044.20.8231.47356312470.4150240.20.8831.4756Comparative Examples12359881286.50.2001.4785285352.835257.50.6311.48603245646.880514.31.2751.48734405372.42,38553.80.6881.4876580117.635083.20.2501.4876 <Evaluation Example 1: Evaluation of filter manufacturability and filterability according to FPI>

[0283] For the lyocell materials of Examples 1 to 6 and Comparative Examples 1 to 5, an FPI was calculated according to Equation 1 below. 2 × CrE / Po

[0284] Meanwhile, when the preparation of a filter for a smoking article from a lyocell material is performed continuously without interruption, filter manufacturability was evaluated to be good. On the other hand, when the preparation of a filter was stopped, or a prepared filter was unsuitable as a filter for a smoking article, filter manufacturability was evaluated to be poor.

[0285] In addition, the maximum suction resistance of each filter for a smoking article was measured according to the KS H ISO 6565 standard. Respective filters had a uniform diameter and all had a rod shape.

[0286] Evaluation results of the filter manufacturability and maximum suction resistance of the lyocell materials of Examples 1 to 6 and Comparative Examples 1 to 5 are as shown in Table 2 below. [Table 2]TargetFPIFilter manufacturabilityMaximum suction resistance (mmHG / rod)Examples124.0Good458244.9Good683333.8Good554457.1Good754526.3Good511674.8Good812Comparative Examples118.8Poor-212.2Poor3553112.8Poor-488.7Poor-58.4Poor-

[0287] It was found that the lyocell materials of Examples 1 to 6 all satisfied an FPI range of 19 to 88. The preparation of filters for a smoking article from the lyocell materials of Examples 1 to 6 were smoothly performed, and it was confirmed that filters including the lyocell materials of Examples 1 to 6 could provide maximum suction resistance suitable for filters for a smoking article.

[0288] On the other hand, it was found that an FPI of Comparative Examples 1, 2, and 5 was less than 19. In particular, the preparation of filters from the lyocell materials of Comparative Example 1 and Comparative Example 5 was not possible. Specifically, in the lyocell materials of Comparative Examples 1 and 5, the clumping between filaments was confirmed, and it was confirmed that unwinding properties were significantly reduced. The lyocell material of Comparative Example 2 was unwound, but it was found that a filter including the lyocell material of Comparative Example 2 did not provide sufficient filterability as a filter for a smoking article.

[0289] In addition, it was found that an FPI of Comparative Example 3 and Comparative Example 4 exceeded 88. As a result, the preparation of filters from the lyocell materials of Comparative Example 3 and Comparative Example 4 was not possible. Specifically, during an unwinding process of the lyocell material of Comparative Example 3, cutting occurred and a filter preparation process was stopped. In the case of the lyocell material of Comparative Example 4, opening could not be sufficiently performed, and it was found that a filter burst due to the clumping of the lyocell material in the filter.

Examples

preparation example

[Preparation Example]

[0272]Cellulose pulp having an alpha-cellulose content of 93.9 % and a DPw of 820 was mixed with an NMMO / H 2 O solvent having a propyl gallate content of 0.01 wt% to prepare a spinning dope for preparing tow having a concentration of 11 wt%. While a spinning temperature of a spinning nozzle was maintained at 110 °C, a discharge amount and a spinning speed were appropriately adjusted, and the spinning dope was spun.

[0273]The spinning dope with a filament phase discharged from the spinning nozzle was supplied to a coagulating solution (a coagulating solution having a concentration of 75 wt% water and 25 wt% NMMO and a temperature of about 25 °C) in a coagulation tank through an air gap section. In this case, cooling air in the air gap section primarily solidifies the spinning dope at a temperature of 8 °C and an air flow rate of 120 Nm 3< / h. In addition, the concentration of the coagulating solution was continuously monitored by using a sensor and a refractometer...

examples 1 to 6

Examples 1 to 6

[0278]Lyocell materials were prepared according to Preparation Example, and values of a moisture content, pressing pressure, crimp energy CrE, porosity Po, density A, and density B of a filament were as shown in Table 1 below.

examples124.0

Examples124.0Good458

244.9Good683

333.8Good554

457.1Good754

526.3Good511

674.8Good812

Claims

1. A lyocell material comprising lyocell multifilaments to which crimps have been imparted, wherein the lyocell material has a filter process index (FPI) of 19 to 88, represented by Equation 1 below: 2 × CrE / Po wherein, in Equation 1, CrE is crimp energy, and Po is porosity represented by Equation 2 below: 1 − density A / density B × 100 wherein, in Equation 2, density A is an apparent density of the lyocell material, and density B is a true density of the lyocell material.

2. The lyocell material of claim 1, wherein CrE is in a range of 400 mJ to 2,300 mJ, and / or wherein Po is in a range of 15 % to 83 %, and / or wherein density A is in a range of 0.300 g / cm3 to 1.200 g / cm3, and / or wherein density B is in a range of 1.40 g / cm3 to 1.50 g / cm3.

3. The lyocell material of claim 1, satisfying both Condition 1 and Condition 2 below: [Condition 1] CrE is in a range of 400 mJ to 2,300 mJ, and [Condition 2] Po is in a range of 15 % to 83 %.

4. The lyocell material of claim 1, satisfying at least one of Condition 1-1 and Condition 2-1 below: [Condition 1-1] CrE is in a range of 550 mJ to 1,650 mJ, and [Condition 2-1] Po is in a range of 40 % to 70 %.

5. The lyocell material of claim 1, wherein the number of the crimps is 3.94 ea / cm (10 ea / inch) to 23.64 ea / cm (60 ea / inch).

6. The lyocell material of claim 1, wherein the lyocell multifilaments have a single fiber fineness of 1.67 dtex to 12.21 dtex (1.5 denier to 11.0 denier).

7. The lyocell material of claim 1, having a total fineness of 1,667 tex to 6,111 tex (15,000 denier to 55,000 denier).

8. The lyocell material of claim 1, wherein the lyocell multifilaments comprise one or more monofilaments, and at least one of the one or more monofilaments has a multi-lobal cross section.

9. The lyocell material of claim 1, wherein the lyocell material is lyocell tow, and / or wherein the lyocell material is a lyocell laminate.

10. The lyocell material of claim 1, wherein the lyocell material is used for a filter for a smoking article.

11. The lyocell material of claim 1, wherein the lyocell material is not for use in tire cords or garments.

12. A filter for a smoking article, comprising the lyocell material of any one of claims 1 to 11.

13. A smoking article comprising the filter for a smoking article of claim 12.

14. A method of preparing a lyocell material, the method comprising: lyocell dope spinning; coagulating, and obtaining lyocell multifilament; washing; emulsion treatment; and crimp imparting, wherein the method further comprises stacking and pressing, and a filter process index (FPI) measured from a lyocell material after the stacking and pressing is in a range of 19 to 88.

15. The method of claim 14, wherein a pressing pressure in the stacking and pressing is in a range of 196 N / cm2 to 588 N / cm2 (20 kgf / cm2 to 60 kgf / cm2), and / or wherein a moisture content of the lyocell material measured before the crimp imparting is in a range of 150 % to 400 %.

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