CN118201507A

CN118201507A - Cigarette filter including lyocell tow and method for making the same

Info

Publication number: CN118201507A
Application number: CN202280073900.1A
Authority: CN
Inventors: 梁真哲; 金守镐; 马京培; 郑奉洙; 河成薰; 郑钟喆; 秦尚佑; 李廷薰; 徐昇潼; 黃永男
Original assignee: Kolon Industries Inc; KT&G Corp
Current assignee: Kolon Industries Inc; KT&G Corp
Priority date: 2021-12-07
Filing date: 2022-11-03
Publication date: 2024-06-14
Also published as: EP4403046A4; KR20230085386A; US20250000136A1; JP2024537177A; EP4403046A1; JP7758272B2; WO2023106643A1

Abstract

The present invention provides a cigarette filter, which includes: a lyocell tow made of a plurality of lyocell fibers, an adhesive for bonding the lyocell fibers to each other, and a solvent dispersed in the internal space of the cigarette filter including the lyocell tow; the solvent includes a polyol. According to a specific example of the present invention, the polyol is a diol having an alkylene group of C1 to C4. The cigarette filter of a specific example of the present invention overcomes the material problems of the previous lyocell tow and has excellent hardness.

Description

Cigarette filter comprising lyocell tow and method of making same

Technical Field

The present invention relates to cigarette filters comprising lyocell tow. In particular, the invention relates to a cigarette filter comprising: a lyocell tow made of a plurality of lyocell fibers, a binder for binding the lyocell fibers to each other, and a solvent dispersed in an inner space of a cigarette filter including the lyocell tow; the solvent contains a polyol.

The present application claims priority from korean patent application No. 10-2021-0173493, filed on 7 of 12 months of 2021, the entire contents of which are incorporated herein by reference.

Background

Typically, to make cigarettes, first, the desired flavor and taste are achieved by blending and processing various tobacco leaves (leaf tobaccos). Thereafter, the processed tobacco leaves are cut to produce cut tobacco (cut tobacco leaf), and the cut tobacco is rolled up with a cigarette paper (CIGARETTE PAPER) to obtain a filter-less cigarette. Thereafter, the filter is attached to the unfiltered cigarette as desired.

The cigarette paper may be made of hemp (flag), wood pulp, etc., and when burned, it is required to maintain combustibility and taste of the cigarette. The cigarette filter may include activated carbon, flavoring, etc., may be comprised of a single filter or multiple filters, and is surrounded by a cigarette filter plug wrap (CIGARETTE FILTER WRAPPING PAPER). The tobacco plug portion and the cigarette filter are joined by a tipping paper (TIPPING PAPER), which may include fine holes.

Conventional cigarette filters use cellulose acetate tow (tow) from wood pulp, which is cellulose extracted and acetylated, and recently, research into environmental materials as alternative materials is underway for natural environmental protection and cost saving. For example, the following tows are being developed: unlike cellulose acetate, lyocell (lyocell) fibres are used which fibrillate cellulose itself.

In cigarette filters, hardness is an important index related to consumer demand and workability in cigarette manufacture. When a cigarette filter is manufactured using a tow of a plurality of fiber filaments, the hardness of the cigarette filter is not suitable because of its low hardness, and it is necessary to increase the hardness to a predetermined level or more for use as a cigarette filter. For example, the method of increasing the hardness of the filter includes a method using a curing agent and a method using a plasticizer (plasticizer). The method for using the curing agent comprises the following steps: the method of stiffening the filter by bonding the filaments with a substance of an adhesive nature to impart stiffness to the filter. The method for using the plasticizer is as follows: the fibers themselves are partially dissolved or plasticized with a specific substance to form joints between the fibers, and then plasticized.

The conventional cellulose acetate uses a plasticizer (glyceryl triacetate (TRIACETIN) and triethyl citrate (TRIETHYL CITRATE)) to partially dissolve the filaments and uses the principle of mutual solidification between the filaments to impart hardness to the cigarette filter. However, lyocell fibers do not currently have plasticizers, and thus, there is a need to develop hardness enhancers suitable for lyocell fibers.

The present inventors have recognized the technical problems of the above-mentioned lyocell fiber materials and have continuously studied lyocell tows excellent in functionality suitable for use as cigarette filters, thereby completing the present invention.

Prior art literature

Patent literature

Patent document 1: korean laid-open patent publication No. 10-2015-0116112

Disclosure of Invention

Technical problem

A cigarette filter comprising lyocell tow as an environment-friendly material, which can solve the problems of materials such as the hardness of the lyocell tow, the workability in processing to ensure the hardness, and the like.

Technical proposal

According to a first aspect of the present invention there is provided a cigarette filter comprising: a lyocell tow made of a plurality of lyocell fibers, a binder for binding the lyocell fibers to each other, and a solvent dispersed in an inner space of a cigarette filter including the lyocell tow; the solvent contains a polyol.

In one embodiment of the present invention, the polyol is a glycol having a C1 to C4 alkylene group.

In one embodiment of the present invention, the above polyol is contained in an amount of 0.5 to 25 parts by weight based on 100 parts by weight of the lyocell filament bundles.

In one embodiment of the present invention, the binder is hydroxypropyl methylcellulose, hydroxypropyl cellulose, polyvinyl alcohol, ethylene-vinyl acetate, polyvinyl acetate, polyvinylpyrrolidone, polyester, or a combination thereof.

In one embodiment of the present invention, the above binder is contained in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the lyocell filament bundles.

In one embodiment of the present invention, the solvent further comprises a monohydric alcohol, wherein the monohydric alcohol is methanol, ethanol, propanol, or a combination thereof.

According to a second aspect of the present invention, there is provided a method of manufacturing the above cigarette filter, the above method comprising the steps of: manufacturing a lyocell tow from a plurality of lyocell fibers; preparing a binder solution by mixing a binder and a solvent; spraying an adhesive solution on the lyocell tows, and preserving the lyocell tows in a mode that the lyocell fibers are mutually combined through an adhesive; and wrapping the lyocell fibers around a bundle of lyocell fibers bonded by an adhesive by using a roll paper to manufacture a cigarette filter.

In one embodiment of the present invention, the above polyol is contained in an amount of 5 to 50 parts by weight based on 100 parts by weight of the binder solution.

In one embodiment of the invention, the solvent further comprises a monohydric alcohol.

In one embodiment of the present invention, the monohydric alcohol is methanol, ethanol, propanol, or a combination thereof.

In one embodiment of the present invention, the above-described monohydric alcohol is contained in an amount of 5 to 60 parts by weight based on 100 parts by weight of the binder solution.

In one embodiment of the present invention, the binder solution described above is sprayed to the lyocell filament bundles in an amount of 5 to 30 parts by weight based on 100 parts by weight of the lyocell filament bundles.

Effects of the invention

The cigarette filter according to an embodiment of the present invention includes lyocell tow which is an environment-friendly material, overcomes the problems of the conventional lyocell tow, and has excellent hardness.

Unlike other cigarette filters using lyocell tow, the cigarette filter according to one embodiment of the present invention can achieve the above-described excellent hardness even without being dried for a long period of time under high temperature conditions, and thus, when the cigarette filter is manufactured, the workability can be improved and the productivity can be improved.

The cigarette filter according to an embodiment of the present invention includes a polyol which substantially contributes to the binder to improve the hardness of the cigarette filter, and also, in the manufacturing process of the cigarette filter, performs a function as a mold release agent when performing roll processing, thereby reducing the defects of the product and improving the workability.

Drawings

Fig. 1 is a diagram showing a schematic structure of a smoking article according to an embodiment of the present invention.

Detailed Description

Specific examples are described in detail below with reference to the drawings. Note that, when reference numerals are given to constituent elements of respective drawings, the same reference numerals are given to the same constituent elements as much as possible even when they appear in different drawings. When specific examples are described, if it is determined that specific descriptions about known structures or functions are not included in the understanding of the specific examples, detailed descriptions thereof will be omitted.

When describing the components of the specific example, the terms of the first, second, A, B, (a), (b), and the like may be used. Such terms are merely used to distinguish one component from another, and the nature, order, sequence, etc. of the corresponding components are not limited to the terms thereof. It will be understood that when an element is referred to as being "connected," "coupled" or "coupled" to another element, it can be directly connected or coupled to the other element or other elements can be "connected," "coupled" or "coupled" between the elements.

The components having functions common to those included in one embodiment will be described using the same names in another embodiment. Unless stated to the contrary, the description described in one embodiment is also applicable to other embodiments, and the detailed description will be omitted insofar as repeated.

In this specification, the term "smoking article" refers to something that can produce an aerosol, such as a cigarette (cigarette), cigar, or the like. The smoking article may comprise an aerosol-generating substance or an aerosol-forming substrate. Also, the smoking article may comprise solid materials based on tobacco raw materials, such as lamina, leaf, reconstituted tobacco, and the like. The smoking material may comprise a volatile compound. The smoking article described above may comprise several segments with respective functionalities, such segments being indicated by the "… … portion". In the present specification, the smoking article may be a heated cigarette used together with an aerosol generating device (not shown) such as an electronic cigarette apparatus, as well as a combustion type cigarette.

In the present specification, the terms "upstream" and "downstream" are terms indicating the relative positions of the various segments constituting the smoking article, based on the direction in which air is drawn when the user uses the smoking article. The smoking article comprises an upstream end (i.e. an inlet portion) and a downstream end (i.e. an outlet portion) opposite thereto. When using the smoking article, the user may bite into the downstream end of the smoking article. The downstream end is downstream of the upstream end, and furthermore, the term "end" may also be described by a "tip".

The present invention relates to a cigarette filter applicable to a smoking article, and according to one embodiment of the present invention, the cigarette filter comprises: lyocell tow (tow) made from a plurality of lyocell fibres; a binder for binding the lyocell fibers to each other; and a solvent dispersed in an inner space of the cigarette filter including the lyocell tow. The lyocell fibers are environment-friendly fibers made from cellulose extracted from wood pulp. The lyocell filament bundles are bundles formed by cross-linking adjacent lyocell fibers. According to an embodiment of the present invention, the lyocell fiber may have a denier of 1.0 to 12.0. According to one embodiment of the present invention, the lyocell fiber bundles constituting the lyocell fiber bundles may have a denier of 15000 denier to 45000 denier. The binder solution is prepared by mixing a binder suitable for the above lyocell fibers with a solvent and spraying it onto the lyocell strands, whereby the lyocell strands can form a structure having a certain level of hardness or more. After spraying and over time, the adhesive and a portion of the solvent components do not flow out and can be included in the final cigarette filter.

The binder included in the above cigarette filter imparts a certain level of hardness or more to the lyocell tow by bonding the lyocell fibers to each other. The binder is suitable for application to lyocell fibers, and any binder can be used as long as it is a conventional binder known in the art. According to an embodiment of the present invention, the adhesive may use hydroxypropyl methylcellulose (hydroxyl propyl methyl cellulose, HPMC), hydroxypropyl cellulose (hydoroxy propyl cellulose, HPC), polyvinyl alcohol (poly vinyl alcohol, PVA), ethylene-vinyl acetate (ETHYLENE VINYL ACETATE, EVA), polyvinyl acetate (poly VINYL ACETATE, PVAc), polyvinylpyrrolidone (poly vinyl pyrrolidone, PVP), polyester (polyester), or a combination thereof, and in particular, the adhesive may use hydroxypropyl methylcellulose, polyester, or a combination thereof.

The polyester is a synthetic resin obtained by reacting a polyvalent organic acid with a polyhydric alcohol, and has an appropriate resistance to water and various compounds. According to one embodiment of the present invention, the polyester is a copolymer of an aromatic monomer and an aliphatic monomer. The aromatic monomer imparts structural stability to the polyester and the aliphatic monomer imparts structural flexibility to the polyester, and thus the polyester including the aromatic monomer and the aliphatic monomer is easily bonded to other components such as lyocell fiber, and thus can impart functionality as an adhesive. The aromatic monomer may be a polyvalent organic acid or a polyhydric alcohol, and the aliphatic monomer may be a polyvalent organic acid or a polyhydric alcohol.

According to one embodiment of the present invention, the aromatic monomer is a dicarboxylic acid having a C5 to C12 arylene or heteroarylene group. By way of example, the above-mentioned dicarboxylic acids having arylene or heteroarylene groups of C5 to C12 may be phthalic acid, terephthalic acid, isophthalic acid. According to one embodiment of the present invention, the aliphatic monomer is a diol having a C1 to C6 alkylene group, a dicarboxylic acid having a C2 to C12 alkylene group, or a combination thereof. As an example, the diol having an alkylene group of C1 to C6 is ethylene glycol, and the dicarboxylic acid having an alkylene group of C2 to C12 is sebacic acid. In the case of polyesters, the carboxylic acid groups and the hydroxyl groups can be condensed in a ratio of 1:1, whereby as monomers having carboxylic acid groups, the above-mentioned dicarboxylic acids having arylene or heteroarylene groups of C5 to C12, dicarboxylic acids having alkylene groups of C2 to C12, or combinations thereof can be used; as the monomer having a hydroxyl group, a diol having a C1 to C6 alkylene group may be used. The arylene, heteroarylene, or alkylene group may be in a substituted or unsubstituted state, and in the substituted state, a substituent commonly known in the art such as an alkyl group of C1 to C4, an alkoxy group of C1 to C4, a halogen group, or the like may be substituted on the main chain of the arylene, heteroarylene, or alkylene group.

The binder may be applied to the lyocell filament bundles in the form of a binder solution together with a solvent, and the binder does not leak out even if the lyocell filament bundles are dried or left for a long period of time after the application of the binder, and the binder is located between the lyocell fibers to increase the hardness of the lyocell filament bundles. According to one embodiment of the present invention, the binder described above is contained in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the lyocell filament bundles. Specifically, the content of the adhesive may be 0.1 part by weight or more, 0.2 part by weight or more, 0.3 part by weight or more, 0.4 part by weight or more, and may be 5 parts by weight or less, 4.5 parts by weight or less, 4 parts by weight or less, 3.5 parts by weight or less, 3 parts by weight or less, 2.5 parts by weight or less, and may be 0.1 to 5 parts by weight, 0.2 to 4 parts by weight, 0.3 to 3 parts by weight. When the above binder is applied in the above range, the function of the lyocell tow as a basic filter can be not reduced, and at the same time, the hardness can be increased to an appropriate level.

The solvent contained in the above cigarette filter is basically contained in the binder solution for dispersing the binder, and if the binder solution is sprayed onto the lyocell tow and dried or left for a long time, a part of the solvent is removed. The solvent that is not removed is located as a constituent inside the cigarette filter including the lyocell tow, imparting additional functionality to the cigarette filter. The solvent remaining in the cigarette filter comprises a polyol. Wherein the polyhydric alcohol means a compound containing two or more hydroxyl groups. The above polyol functions as a release agent when processed by a mechanical roller or the like in order to apply lyocell tow to a cigarette filter. Specifically, when the lyocell filament bundles are processed by a mechanical roller or the like without a release agent, a phenomenon in which the lyocell filament bundles are caught up by the mechanical roller or the like may occur due to the cohesive force of the adhesive or the like, and the lyocell filament bundles including the polyol may reduce such a phenomenon, so that the processability may be improved. In addition, when the above polyol is applied to the lyocell filament bundles, it is contained between the gaps of the lyocell fibers together with the binder even if it is not dried at a particularly high temperature for a long period of time, thereby contributing to an increase in the hardness of the lyocell filament bundles in a short period of time. Thus, when a solvent containing a polyhydric alcohol is used, the drying time can be significantly shortened, and the productivity of the cigarette filter can be improved.

According to one embodiment of the present invention, the polyol is a glycol having a C1 to C4 alkylene group. The above diol refers to a compound having 2 hydroxyl groups, also referred to as glycol. The above 2 hydroxyl groups may be linked by a C1 to C4 alkylene group, wherein the carbon number of the alkylene group means the carbon number directly linked between 2 hydroxyl groups. The above alkylene group is present in a substituted or unsubstituted state, and in the case of substitution, substituents well known in the art, such as a main chain of the alkylene group, a C1 to C3 alkyl group, a C1 to C3 alkoxy group, a halogen group, and the like, may be substituted. According to an embodiment of the present invention, the polyol may be propylene glycol. The propylene glycol is a polyol having a chain of an appropriate length, and may be more preferably a compound having the above-mentioned functionality.

The above polyol can be applied to the lyocell tow in the form of a binder solution together with a binder and other solvents, and remain in the lyocell tow or a cigarette filter to which it is applied without any change before and after drying, whereby the above functionality including improvement in the workability including hardness and the like can be imparted. According to one embodiment of the present invention, the above polyol is contained in an amount of 0.5 to 25 parts by weight based on 100 parts by weight of the lyocell filament bundles. Specifically, the content of the above polyol may be 0.5 parts by weight or more, 0.6 parts by weight or more, 0.7 parts by weight or more, 0.8 parts by weight or more, 0.9 parts by weight or more, 1 part by weight or more, and may be 25 parts by weight or less, 20 parts by weight or less, 15 parts by weight or less, 10 parts by weight or less, 5 parts by weight or less, and may be 0.5 parts by weight to 10 parts by weight, 0.7 parts by weight to 7 parts by weight, 1 part by weight to 5 parts by weight. When the above polyol is used in the above range, additional functionality can be imparted to the cigarette filter without degrading the performance of the lyocell tow as a basic filter.

According to one embodiment of the present invention, the solvent comprises a monohydric alcohol, which is methanol, ethanol, propanol, or a combination thereof. The specific method of adding the above monohydric alcohol will be described in the manufacturing method section. The monohydric alcohol is a component having higher volatility than water, and a large amount of the monohydric alcohol can be lost after drying, but in the case where the drying process is not performed and the filter is stored at normal temperature, a certain level or more of the monohydric alcohol can be detected in the final cigarette filter. The monohydric alcohol may replace water in the solvent of the binder solution and thus not only contributes to increasing the hardness of the cigarette filter, but also has bactericidal properties and thus may exhibit additional functionality when applied to the lyocell tow. According to one embodiment of the present invention, the above monohydric alcohol is contained in an amount of 1 to 500 parts by weight based on 10000 parts by weight of lyocell filament bundles. The content of the monohydric alcohol has a higher volatility than that of the polyhydric alcohol or water, and therefore, the content of the monohydric alcohol has a higher volatility, but in the case of reducing the drying process and storing at room temperature according to an embodiment of the present invention, a monohydric alcohol having a level of not less than a certain level can be detected as compared with the case where the monohydric alcohol is not added, and thus, the lower limit is more significant than the upper limit in the content range.

A cigarette filter comprising lyocell tow according to one embodiment of the present invention has excellent hardness by bonding with an adhesive. According to an embodiment of the present invention, the cigarette filter has a hardness of 85% or more. Specifically, the hardness of the cigarette filter may be 85% or more, 86% or more, 87% or more, 88% or more, or 89% or more. The hardness of the cigarette filter is a value obtained by digitizing the degree of retention of the diameter of the cigarette filter when the cigarette filter is pressed with a constant horizontal force in the vertical direction, and specifically, the hardness can be calculated by the following expression 1.

Calculation formula 1:

filter hardness (%) = [ D-a ]/d×100

Where D represents the filter diameter (mm) and a represents the distance (mm) from 300g of weight down (filter pressed). When calculating the hardness of the cigarette filter described above, the desired measurement can be obtained using means commonly used in the art, for example, the DHT 200 ^TM available from Filtrona corporation. The force applied when measuring the hardness takes into account the force applied when the actual smoker grips the cigarette. The hardness values of 85% or more obtained by the cigarette filter according to an embodiment of the present invention are technically significant in the following respects: the hardness is ensured by using lyocell tow which is an environment-friendly material at a level that can replace a cigarette filter made of conventional cellulose acetate. Further, the cigarette filter according to the embodiment of the present invention can achieve an excellent hardness value of 85% or more even after the lapse of a time period during which the binder can adhere under normal temperature conditions without performing a drying process under high temperature conditions, and thus can significantly improve the workability in manufacturing the product.

The cigarette filter can be manufactured by the following manufacturing method. The manufacturing method comprises the following steps: manufacturing lyocell tows by using lyocell fibers; preparing a binder solution by mixing a binder and a solvent; spraying an adhesive solution on the lyocell tows, and preserving the lyocell tows in a mode that the lyocell fibers are mutually combined through an adhesive; and wrapping the lyocell fibers around a bundle of lyocell fibers bonded by an adhesive by using a roll paper to manufacture a cigarette filter. The above-described manufacturing method basically relates to a method of manufacturing the above-described cigarette filter, and therefore, a portion specified in the above-described matters will be omitted, and the features of the manufacturing method will be described in more detail below.

First, lyocell filament bundles are produced using a plurality of lyocell fibers. The manufactured lyocell filament bundles have bundle shapes formed by cross-linking between adjacent lyocell fibers. At this time, a step of expanding the tow by blooming (blooming) is additionally performed. When the tow is expanded by the above-described blooming step, the binder solution sprayed thereafter easily penetrates between the lyocell fibers constituting the lyocell tow.

Thereafter, an adhesive solution is prepared by mixing an adhesive and a solvent. The binder solution is sprayed on the lyocell filament bundles to improve the functionality such as the hardness of the lyocell filament bundles. After spraying, a portion of the components of the binder solution may be lost through the drying or storage process, and thus, the components of the binder solution may be different from the components that make up the components of the cigarette filter. The above binder may be embodied according to the above, and the ingredients will not be lost after drying or storage, so that the amount of the lyocell tow supplied by spraying remains almost unchanged in the final cigarette filter. According to one embodiment of the present invention, the above-mentioned binder is contained in an amount of 5 to 40 parts by weight based on 100 parts by weight of the binder solution. Specifically, the content of the adhesive may be 5 parts by weight or more, 6 parts by weight or more, 7 parts by weight or more, 8 parts by weight or more, 9 parts by weight or more, 10 parts by weight or more, and may be 40 parts by weight or less, 35 parts by weight or less, 30 parts by weight or less, 25 parts by weight or less, 20 parts by weight or less, and may be 5 parts by weight to 40 parts by weight, 7 parts by weight to 30 parts by weight, 10 parts by weight to 20 parts by weight. When the binder solution is formed in the above range, the above binder can be easily applied to the lyocell tow by spraying.

The solvent includes a polyhydric alcohol and water. In the case where the entire solvent is composed of a polyol, the viscosity is too high to disperse the adhesive easily. Water can be contained in the same amount as the balance of the proportion of the solvent such as polyol and the like, and a part is lost during drying. According to one embodiment of the present invention, the above polyol is contained in an amount of 5 to 50 parts by weight based on 100 parts by weight of the binder solution. Specifically, the content of the polyhydric alcohol may be 5 parts by weight or more, 6 parts by weight or more, 7 parts by weight or more, 8 parts by weight or more, 9 parts by weight or more, 10 parts by weight or more, and may be 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, and may be 5 parts by weight to 50 parts by weight, 7 parts by weight to 40 parts by weight, 10 parts by weight to 30 parts by weight. When the above polyol is used in the above range, additional functionality can be imparted to the cigarette filter without degrading the function of the lyocell tow as a basic filter.

The solvent may further comprise a monohydric alcohol. The monohydric alcohol is a component having higher volatility than water, and a large amount of the monohydric alcohol can be lost after drying, but when stored at normal temperature without drying, a certain level or more can be detected in the final cigarette filter. The monohydric alcohol is a component that can replace water in the solvent of the binder solution, and the water content of the final cigarette filter can be adjusted. According to one embodiment of the present invention, the monohydric alcohol is methanol, ethanol, propanol, or a combination thereof. Specifically, the monohydric alcohol may be ethanol.

In place of water, the above monohydric alcohol may be contained at a level or more. According to one embodiment of the present invention, the above monohydric alcohol is contained in an amount of 5 to 60 parts by weight based on 100 parts by weight of the binder solution. Specifically, the content of the monohydric alcohol may be 5 parts by weight or more, 6 parts by weight or more, 7 parts by weight or more, 8 parts by weight or more, 9 parts by weight or more, 10 parts by weight or more, and may be 60 parts by weight or less, 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, and may be 5 parts by weight to 60 parts by weight, 7 parts by weight to 45 parts by weight, 10 parts by weight to 30 parts by weight. When the above monohydric alcohol is used in the above range, the water content in the cigarette filter can be reduced by an effectively meaningful value.

The binder solution prepared according to the above was sprayed into the lyocell filament bundles. The binder solution is sprayed onto the lyocell tow to such an extent that the problems of hardness and the like of the lyocell tow in terms of materials can be solved without deteriorating the function of the basic filter of the lyocell tow. According to one embodiment of the present invention, the binder solution is sprayed to the lyocell filament bundles in an amount of 5 to 30 parts by weight based on 100 parts by weight of the lyocell filament bundles. Specifically, the amount of the binder solution sprayed may be 5 parts by weight or more, 6 parts by weight or more, 7 parts by weight or more, 8 parts by weight or more, 9 parts by weight or more, 10 parts by weight or more, and may be 30 parts by weight or less, 28 parts by weight or less, 26 parts by weight or less, 24 parts by weight or less, 22 parts by weight or less, 20 parts by weight or less, and may be 5 parts by weight to 30 parts by weight, 7 parts by weight to 24 parts by weight, 10 parts by weight to 20 parts by weight. When the binder solution is sprayed in the above range, the functionality such as the hardness of the lyocell yarn can be improved. The method of spraying the above binder solution may use methods generally used in the art, and is not particularly limited. For example, the above-mentioned spraying of the adhesive solution may be performed by nozzle spraying, brush spraying, electric spraying, or the like.

After the binder solution is sprayed onto the lyocell filament bundles, the binder is stored in such a manner that the binder adheres and bonds the lyocell fibers to each other by the binder. This process is a long-term drying process different from high temperature, and for example, the binder solution can be stored at room temperature for 6 hours and can be used for the next operation sufficiently, so that the workability in the production of the product can be improved.

The cigarette filter is manufactured by wrapping a bundle of lyocell fibers, which is formed by bonding lyocell fibers with an adhesive, with a roll paper. According to the requirements, the lyocell tow can be processed by using a mechanical roller or a cutter and the like to be suitable for the specifications of the cigarette filter tip.

The cigarette filter described above can be applied to smoking articles. Fig. 1 provides a diagram showing a brief structure of a smoking article according to an embodiment of the present invention. The smoking article 100 includes a smoking material portion 10 and a filter portion 20, and the cigarette filter is applied to the filter portion 20 of the smoking article 100. In the above-described smoking article 100, the smoking material section 10 is located upstream with respect to the filter section 20.

The smoking material part 10 may be filled with a smoking material such as raw tobacco leaves, platy leaves, or a mixture of tobacco leaves and platy leaves. The processed smoking material may be filled into the smoking material section 10 in sheet form or tobacco form. The smoking material portion 10 may have a rod shape extending long, and the length, the circumference, and the diameter thereof are not particularly limited, but may be adjusted to a size commonly used in the art in consideration of the filling amount of the smoking material, the preference of a user, and the like. The smoking material part 10 may include an aerosol-generating substance of at least one of glycerin, propylene glycol, ethylene glycol, dipropylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, and oleyl alcohol. The smoking material portion 10 described above may contain other additives such as flavoring agents, humectants and/or acetate compounds. The aerosol-generating substance and the additive substance may be contained in a smoking substance.

The filter portion 20 is located downstream of the smoking material portion 10, and functions as a filter through which a user passes before inhaling the aerosol generated in the smoking material portion 10. The filter portion 20 described above may be manufactured from a variety of materials or forms. The filter portion 20 according to an embodiment of the present invention basically includes the above-described cigarette filter including a bundle of lyocell fibers bonded by an adhesive. The cigarette filter comprising lyocell tow described above may replace all or a portion of the filter portion 20 of an existing smoking article, and in the case of replacing a portion of the filter portion 20 of an existing smoking article, filter materials that have been used heretofore may be used together. As the conventional filter material, for example, a cellulose acetate filter, a hollow tube filter, or the like can be used.

In fig. 1, a single filter in which the filter portion 20 is made of a single filter is shown, but is not limited thereto. For example, the filter portion 20 may be provided by a double filter or a triple filter having 2 acetate filters, or the like, in order to improve the filtering efficiency. Further, although not shown, a breakable capsule (not shown) having a structure in which a coating film surrounds a content liquid containing a flavor may be included in the filter portion 20.

The outside of the smoking material part 10 and the filter part 20 may be wrapped with wrapping paper 30a or wrapping paper 30 b.

The smoking material part 10 may be wrapped with a smoking material part wrapper 30 a. Some of the cigarette smoke generated during the combustion of the conventional smoking material segment 10 is released into the atmosphere through the smoking material segment wrapper 30a before passing through the cigarette filter, and the sidestream smoke gives an unpleasant sensation to the indirect smoker. In order to reduce such sidestream smoke, attempts have been made to add fillers such as magnesium oxide, titanium oxide, cerium oxide, aluminum oxide, calcium carbonate, zirconium carbonate, etc. to conventional cigarette paper, but when such fillers are simply applied to reduce sidestream smoke, smoke feeling is reduced, or combustion extinction, soot integrity reduction, etc. occur, it is difficult to solve the above problems by appropriately combining substances added to the fillers. In order to reduce sidestream smoke and prevent smoke from being perceived, soot from being reduced in integrity, and combustion from being extinguished, the smoking material portion wrapper 30a of one embodiment of the present invention employs a filler of mixed magnesium oxide (MgO and/or Mg (OH) ₂) and calcium carbonate (CaCO ₃).

The filter 20 may be wrapped with filter wrapper 30 b. The filter wrapper 30b may be made of roll paper having oil resistance, and an aluminum foil may be further included on the inner side surface of the filter wrapper 30 b.

The smoking material portion 10 wrapped with the above-described smoking material portion wrapping paper 30a and the filter portion 20 wrapped with the filter portion wrapping paper 30b may be combined and wrapped with the tipping paper 40. As shown in fig. 1, the tipping paper 40 may surround at least a portion (e.g., a downstream partial region) of the smoking material section wrapper 30a and the outer periphery of the filter section wrapper 30 b. In other words, at least a part of the smoking material section 10 and the filter section 20 are also wrapped with the tipping paper 40 and can be physically joined. According to an embodiment of the present invention, the tipping paper 40 may be manufactured from a non-porous roll paper that has not been subjected to oil resistance treatment, but is not limited thereto. The tipping paper 40 may also prevent the filter portion 20 from burning by containing a non-combustible substance, but is not limited thereto.

The constitution of the present invention and effects according to the constitution will be described in more detail below with reference to examples and comparative examples. However, the present examples are intended to more specifically explain the present invention, and the scope of the present invention is not limited to these examples.

Examples

Example 1

Lyocell tow having tow fiber bundles of about 35000 denier was made and used with 1 lyocell fiber having a fiber bundle of about 3.0 denier. And, a binder solution as a mixture of a binder and a solvent was prepared. Specifically, the above adhesive solution is prepared by adding 10 weight percent of polyester (copolymer of phthalic acid and sebacic acid and ethylene glycol), weight average molecular weight (M _w) =3000-6000) to 90 weight percent of solvent (mixed solvent of 30 weight percent of propylene glycol, 10 weight percent of ethanol, 50 weight percent of water), based on the total weight of the adhesive solution. The prepared binder solution was sprayed to the lyocell tows by spray nozzle spraying. The binder solution was sprayed at 15 weight percent based on the weight of the lyocell filament bundles and stored at normal temperature for 6 hours, thereby producing lyocell filament bundles including a binder. Cigarette filters having an axial length of about 108mm and a circumference of about 24.20mm were manufactured by wrapping the prepared lyocell tow with a wrapping paper.

Example 2

A cigarette filter was manufactured by the same method as in example 1, except that 3 weight percent of polyester and 7 weight percent of hydroxypropyl methylcellulose (Pharmacoat 606) were used instead of 10 weight percent of polyester in the binder solution.

Example 3

As the solvent of the binder solution, a cigarette filter was manufactured by the same method as in example 2, except that 90 weight percent of the solvent (a mixed solvent of 30 weight percent of propylene glycol, 30 weight percent of ethanol, 30 weight percent of water) was used instead of 90 weight percent of the solvent (a mixed solvent of 30 weight percent of propylene glycol, 10 weight percent of ethanol, 50 weight percent of water).

Comparative example 1

The cigarette filter is manufactured without spraying the binder solution onto the lyocell tow.

Comparative example 2

A cigarette filter was manufactured by the same method as in example 1, except that 90 weight percent of water was used instead of 90 weight percent of the solvent (a mixed solvent of 30 weight percent of propylene glycol, 10 weight percent of ethanol, and 50 weight percent of water) as the solvent of the binder solution.

Comparative example 3

A cigarette filter was manufactured by the same method as in example 2, except that 90 weight percent of water was used instead of 90 weight percent of the solvent (a mixed solvent of 30 weight percent of propylene glycol, 10 weight percent of ethanol, and 50 weight percent of water) as the solvent of the binder solution.

Experimental example

Experimental example 1: hardness assessment of cigarette filters

The hardness of cigarette filters manufactured according to examples 1 to 3 and comparative examples 1 to 3 was measured. Specifically, when measuring the hardness of a cigarette filter, it is measured using a filter hardness measuring instrument (DHT 200 ^TM of Filtrona corporation) and the following calculation formula 1.

Calculation formula 1:

filter hardness (%) = [ D-a ]/d×100

Where D denotes the filter diameter and a denotes the distance (mm) from 300g of weight down (filter pressed).

TABLE 1

	Hardness (%)
		Example 1	92.1
Example 2	89.8
		Example 3	93.3
Comparative example 1	83.5
		Comparative example 2	82.8
Comparative example 3	81.3

According to table 1, when a binder solution containing a polyol is used as a solvent for the binder, excellent hardness of 85% or more can be ensured even if the binder solution is not dried particularly under high temperature conditions for a long period of time, but is stored only for 6 hours under normal temperature conditions. This not only significantly shortens the drying time, but also has little variation in hardness depending on drying, and therefore contributes to improvement in the process and productivity when a cigarette filter is manufactured by ensuring stable hardness.

Further, in the case of using a monohydric alcohol together with a polyhydric alcohol, the moisture content can be significantly reduced, and therefore, as in comparative examples 2 and 3, the phenomenon that the functionality of the adhesive agent cannot be sufficiently exhibited due to moisture at the initial stage of spraying the adhesive agent solution can be prevented.

Further, when the polyol contained in the binder solution is applied to a subsequent roll processing step or the like, it acts as a release agent, whereby the phenomenon that the lyocell tow is caught in the roll can be prevented, and a suitable amount of the monohydric alcohol is a volatile component as compared with water, and thus, additional functions such as sterilization can be exhibited.

While the embodiments have been described by way of examples and drawings, various modifications and variations may be made by those skilled in the art from the above description. For example, the described techniques may be performed in a different order than the described methods, and/or constituent elements of the described systems, structures, devices, circuits, etc. may be combined or combined in a different manner than the described methods, or substituted with other constituent elements or equivalent technical solutions, as appropriate.

Description of the reference numerals

10: Smoking material part

20: Filter part

30A: smoking material part wrapping paper

30B: filter part wrapping paper

40: Tipping paper

100: Smoking article

Claims

1. A cigarette filter, characterized in that:

include:

A lyocell tow, which is made of a plurality of lyocell fibers,

An adhesive for bonding the lyocell fibers to each other, and

a solvent dispersed in the interior space of a cigarette filter including the lyocell tow described above;

The above-mentioned solvent contains a polyol.

2. The cigarette filter according to claim 1, characterized in that:

The above-mentioned polyol is a diol having an alkylene group of C1 to C4.

3. The cigarette filter according to claim 1, characterized in that:

Based on 100 parts by weight of the lyocell tow, 0.5 parts by weight to 25 parts by weight of the polyol is included.

4. The cigarette filter according to claim 1, characterized in that:

The binder is hydroxypropyl methylcellulose, hydroxypropyl cellulose, polyvinyl alcohol, ethylene-vinyl acetate, polyvinyl acetate, polyvinyl pyrrolidone, polyester or a combination thereof.

5. The cigarette filter according to claim 1, characterized in that:

Based on 100 parts by weight of the lyocell tow, 0.1 parts by weight to 5 parts by weight of the binder are included.

6. The cigarette filter according to claim 1, characterized in that:

The solvent further comprises a monohydric alcohol, and the monohydric alcohol is methanol, ethanol, propanol or a combination thereof.

7. A method for manufacturing a cigarette filter, wherein the cigarette filter is the cigarette filter according to claim 1, characterized in that:

The manufacturing method comprises:

In the first step, a lyocell tow is manufactured using a plurality of lyocell fibers.

In the second step, a binder solution is prepared by mixing a binder and a solvent.

The third step is to spray the adhesive solution onto the lyocell tow and store the lyocell fibers in a manner that the lyocell fibers are bonded to each other by the adhesive, and

The fourth step is to manufacture a cigarette filter by using a lyocell tow formed by wrapping lyocell fibers with a binder and then surrounding the lyocell fibers with a wrapping paper;

The above-mentioned solvent contains a polyol.

8. The method for manufacturing a cigarette filter according to claim 7, characterized in that:

Based on 100 parts by weight of the adhesive solution, 5 parts by weight to 50 parts by weight of the polyol are included.

9. The method for manufacturing a cigarette filter according to claim 7, characterized in that:

The above solvents also include monohydric alcohols.

10. The method for manufacturing a cigarette filter according to claim 9, characterized in that:

The monohydric alcohol is methanol, ethanol, propanol or a combination thereof.

11. The method for manufacturing a cigarette filter according to claim 9, characterized in that:

Based on 100 parts by weight of the binder solution, 5 parts by weight to 60 parts by weight of the monohydric alcohol are included.

12. The method for manufacturing a cigarette filter according to claim 7, characterized in that:

Based on 100 parts by weight of the lyocell tow, 5 to 30 parts by weight of the adhesive solution are sprayed on the lyocell tow.