JPH09103281A - Filter material and cigarette filter using the same - Google Patents

Abstract

(57) Abstract: [PROBLEMS] To provide a filter material which enhances the degradability of cellulose acetate fibers in the presence of water and imparts the disintegration property of the fiber shape of the filter material and the shape of the tobacco filter, and a tobacco filter using the same. To do. SOLUTION: Soluble in a solvent of cellulose acetate,
Hydroxyalkyl cellulose, polyalkylene glycol, glycerin fatty acid ester or alkylene glycol fatty acid ester, which is a water-soluble compound and / or a water-dispersible compound incompatible with cellulose acetate,
A filter material made of cellulose acetate fiber tow containing 50% by weight to 50% by weight, and a tobacco filter containing the filter material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a filter material and a tobacco filter using the same.

[0002]

2. Description of the Related Art Conventionally, most tobacco filters are manufactured from tow of cellulose ester fiber. Cellulose acetate fiber tow is welded with its solvent, triacetin, to maintain the rod shape,
It has the advantage of being easily filterable and applicable to high-speed cigarette making machines.

However, in the cigarette butts after smoking, the filter portion maintains the rod shape without losing its shape, the wrapping paper of the filter portion is not easily peeled off, and the cellulose acetate fiber itself used for the filter is degradable. Since it is slow, the shape of the cigarette butts filter in a natural environment does not easily collapse.

Generally, cigarette filters are collected in ashtrays, trash cans, or the like for disposal after smoking, but in some cases, they are left in the natural environment such as roads, mountains, rivers, lakes and the sea by throwing them away. . The neglect of such cigarette filters causes a problem of environmental pollution and is a social problem.

Impregnation of a cellulose acetate fiber with a plasticizer is disclosed in JP-A-2-39873 (dicarboxylic acid, polycarboxylic acid, or their anhydrides: polyethylene glycol propionate, triethylene glycol diacetate, etc.), Table 63-500422 (glycerin compound), JP-A-60-98978 (plasticizer: polyethylene glycol diacetate), US Pat. No. 4,752,348 (polyalkylene glycol), JP-A-59-227289. Publication (Coating with fatty acid glycerin ester), US Pat. No. 54531
No. 44 (coating with polyalkylene oxide), JP-A No. 7-76632 (plasticizer: lower fatty acid ester of polyhydric alcohol, polyethylene glycol) and the like.

However, in these methods, the plasticizer dissolves the surfaces of the fibers, bonds the fibers to each other to form a three-dimensional network structure, retains the shape of the filter, and has an appropriate hardness for the filter. The function is to add a degree. Therefore, the addition of the plasticizer to the cellulose acetate fiber is not intended to decompose the fiber, but rather has the effect of keeping the filter form stable for a long period of time and suppressing the decomposition of the fiber.

Further, the plasticizer added to the surface of the fiber is
Since it comes into direct contact with cigarette smoke, it has an effect on taste. When the amount of this impregnation is increased, the cellulose acetate fibers are dissolved and fused to deteriorate the quality of the filter. is there.

On the other hand, in JP-A-6-49275,
Excellent in decomposability with a ratio of sulfuric acid amount a remaining in cellulose acetate produced using a sulfuric acid catalyst to alkaline metal (earth) amount b contained in cellulose acetate, b / a of 0.1 to 1. Cellulose acetate fibers have been proposed.

Further, JP-A-7-99959, JP-A-7-500385 and JP-A-6-329832.
Japanese Patent Publication (Starch Acetate) proposes a method of increasing the biodegradability by adding a nitrogen-containing compound, a starch compound and starch acetate to cellulose acetate fibers. However, it is difficult to mix these compounds with cellulose acetate.

Further, Japanese Patent Laid-Open No. 4-126817,
Japanese Unexamined Patent Publication (Kokai) No. 6-146109 proposes a cellulose acetate fiber in which polypropylene glycol or polyethylene glycol is contained in cellulose acetate to improve the deep dyeing property. However, these proposed cellulose acetate fibers are related to clothing fibers, and there is no teaching about increasing the degradability as a filter material, particularly a tobacco filter material.

[0011]

The object of the present invention is to enhance the decomposability of cellulose acetate fibers in the presence of water,
It is an object of the present invention to provide a filter material in which the fiber shape of the filter material and the shape of the tobacco filter are disintegrated, and a tobacco filter using the same.

[0012]

The present invention provides a water-soluble compound and / or a water-dispersible compound which are soluble in a solvent of cellulose acetate and incompatible with cellulose acetate.
The present invention relates to a filter material made of cellulose acetate fiber tow containing 50 to 50% by weight, and a tobacco filter including the filter material.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, the filter material is composed of a cellulose acetate fiber tow, and the cellulose acetate fiber constituting the tow may have any acetylation degree, and the acetylation degree is 48.8% to 56. The cellulose diacetate fiber of less than 0.2% and the cellulose triacetate fiber of acetylation degree of 56.2% or more can be mentioned. Further, the fiber cross section may be either a circular cross section or a modified cross section such as a Y-shaped cross section, and the filter material is composed of a tow having an arbitrary total denier.

In the present invention, it is essential that the cellulose acetate fiber constituting the tow contains a water-soluble compound and / or a water-dispersible compound which is soluble in the solvent of cellulose acetate and incompatible with cellulose acetate. Is.

The water-soluble compound and / or the water-dispersible compound contained therein must be soluble in a solvent such as a cellulose acetate solvent such as acetone or a mixed solvent of methylene chloride / methanol from the viewpoint of fiber formation spinning. is there. If a substance which is insoluble or hardly soluble in the spinning solvent is introduced into the spinning solution, the process passability in fiber production is lowered and the physical properties of the fiber are lowered.

Further, the water-soluble compound and / or the water-dispersible compound contained therein must be incompatible with cellulose acetate in order to separate it from the fiber polymer and enhance the decomposability of the cellulose acetate fiber. In addition, water solubility or water dispersibility is necessary for facilitating separation and elution from the fiber polymer in the presence of water to decompose the cellulose acetate fiber and disintegrate the shape. Further, the water-soluble compound and / or the water-dispersible compound contained therein preferably have a higher degradability than the cellulose acetate fiber.

Examples of such water-soluble compounds include hydroxyalkyl cellulose, polyalkylene glycol, methyl cellulose and polyvinylpyrrolidone. Further, examples of the water-dispersible compound include glycerin fatty acid ester, alkylene glycol fatty acid ester, sorbitan fatty acid ester, sucrose fatty acid ester, lecithin and the like.

More specifically, for example, as hydroxyalkyl cellulose, hydroxypropyl cellulose,
Hydroxyethyl cellulose, polyethylene glycol as polyalkylene glycol, glycerine oleoseite as glycerin fatty acid ester, propylene glycol monooleate as alkylene glycol fatty acid ester, polyethylene sorbitan monooleate, polyethylene sorbitan tristearate, sucrose fatty acid ester as sorbitan fatty acid ester Examples thereof include esters of sucrose and hardened tallow fatty acid.

The water-dispersible compound referred to here is a compound which is dispersed in water in the form of fine particles, including transparent dispersion and emulsified dispersion. Specifically, it is a hydrophilic / lipophilic balance, so-called HLB (Hydrophile-). Lypophil
e Balance) is 2 to 18, preferably 3 to 1.
8 is meant.

Further, in the present invention, the water-soluble compound or the water-dispersible compound is at least one selected from the group of the above compounds, and is not limited to one kind of each, and a mixture of the same kind may be used.

The content of the water-soluble compound and / or the water-dispersible compound in the cellulose acetate fiber is 5 to 50% by weight with respect to the cellulose acetate, and the content is 5%.
If it exceeds 0% by weight, it is difficult to obtain the cellulose acetate fiber by spinning, and if it is less than 5% by weight,
The effect of promoting the decomposition of the cellulose acetate fiber is not exhibited.

In the filter material of the present invention, the cellulose acetate fiber having the constitution is such that the water-soluble compound and / or the water-dispersible compound contained in the fiber are separated and eluted from the fiber in a humid atmosphere, in the presence of water such as water. In addition, the surface of the fiber is made porous, and the increase of the surface area of the fiber enhances the degradability of the cellulose acetate fiber by microorganisms.

Further, the difference between the present invention and the modifiers disclosed in the prior art will be described in detail. BACKGROUND ART Cellulose acetate fibers have been used in many products such as woven and knitting yarns for producing woven fabrics, filter tows used in cigarette filters, and many modifiers thereof have been proposed.

Japanese Unexamined Patent Publication No. 2-138958 discloses a tobacco filter to which creatinine and glycodiamidine are added in order to prevent and deodorize the acetic acid odor generated from the filter. These compounds are for adding a minute amount of a hardly soluble solid to the solvent for spinning cellulose acetate fiber to the outside of the fiber in order to suppress the odor of acetic acid, and it is not possible to accelerate the decomposition of the fiber. I can't expect.

Japanese Patent Application Laid-Open No. 59-105067 discloses 2-methyl-cellulose as a binder for cellulose acetate fibers.
Lower fatty acid esters of 1,3-propanediol are disclosed. This compound is a plasticizer for cellulose acetate fibers, and its function is to dissolve the fiber surfaces, bond the fibers to each other to form a three-dimensional network structure, and maintain the filter shape. It is not intended to be decomposed and has no effect. In this method, the amount is usually 3 to 1 because it is attached to the outside of the fiber.
It is 0% by weight, and when the amount of the impregnation is increased, the cellulose acetate fibers are melted and fused to deteriorate the quality of the filter product.

In Japanese Patent Laid-Open No. 7-99959, a nitrogen-containing compound, especially ammonia, and / or one or more NH groups, which is degradable by a basic decomposition product by a microorganism, is formed inside or on the surface of a cellulose acetate fiber. And / or a basic compound having one or more NH ₂ groups is disclosed. Since these compounds are hardly soluble in the solvent for spinning the cellulose acetate fiber, the amount introduced into the fiber is as small as 5% by weight or less. Also, when such a compound is added to the surface of the fiber, the compound is in direct contact with cigarette smoke, and therefore the amount added is limited due to the influence on taste, and the effects intended by the present invention cannot be obtained.

In Japanese Patent Publication No. 7-500385, a non-toxic water-soluble compound having a poor solubility is contained in a proportion of 0.1 to 5% by weight with respect to cellulose acetate, and the diameter of this compound is larger than that of the fiber. A method of making a cellulose acetate fiber bundle is disclosed that is at least 30% smaller. And, as this water-soluble compound, disaccharides and trisaccharides, organic acids and some inorganic acids, starch, starch derivatives or dextrin are exemplified, but both are hardly soluble in a solvent for cellulose acetate spinning. Is a compound,
It is difficult to obtain good spinnability as in the present invention.

Conventionally, attempts have been made to introduce various additives into the spinning solution. Fibers of cellulose acetate are produced by a dry spinning method in which a cellulose acetate solution is discharged from a spinneret, so if an additive that is insoluble in a spinning solvent is to be introduced, it will be in a suspension state in a spinning solution. Since the stability and the stability of the spinning process are affected, the amount added is limited. For example, titanium oxide is used in cellulose acetate fibers for cigarette filters, but the amount of titanium oxide added is very small, not more than 1% by weight.

Japanese Unexamined Patent Publication (Kokai) No. 6-329832 discloses a composition comprising cellulose acetate and starch acetate and a fiber prepared from the composition. Starch acetate is soluble in the solvent for spinning cellulose acetate and forms a uniform spinning solution, but is insoluble in water. The use of this starch acetate is intended to develop good dyeability, higher yarn elongation, and water content in the fiber, and since it does not dissolve in water, degradability of the fiber which is the object of the present invention. Can't expect.

The filter material of the present invention is particularly useful as a tobacco filter, and a tobacco filter containing the filter material of the present invention is exposed to rainwater or the like when left as a cigarette butts in a natural environment. , The degradability of the cellulose acetate fiber of the filter material is enhanced, and the fiber shape of the filter material and the shape of the tobacco filter are easily collapsed. The decomposition of the cellulose acetate fiber and the collapse of the shape of the tobacco filter are remarkably observed when the cellulose acetate fiber is discarded in water.

The filter material and tobacco filter of the present invention are manufactured by the following method. First, the cellulose acetate fiber tow constituting the filter material is manufactured as follows. The cellulose acetate used in the present invention is a cellulose diacetate having an acetylation degree of 48.8% to less than 56.2%, but an acetylation degree of 56.2% to 62.
5% cellulose triacetate may be used, but from the viewpoint of taste, cellulose diacetate having a degree of acetylation of 48.8% to 56.2% is preferably used.

The flakes of cellulose diacetate or cellulose triacetate are dissolved in a single solvent such as methylene chloride or acetone or a mixed solvent such as methylene chloride and methanol to give a solution concentration of 15 to 35% by weight, preferably 18 to 30% by weight. Prepare a spinning dope as a percentage.

In order to obtain a cellulose acetate fiber tow to be used as a filter material, a water-soluble compound and / or water which is soluble in the solvent of the cellulose acetate exemplified above and incompatible with cellulose acetate when preparing a spinning dope is used. A solution in which a dispersible compound is dissolved and a solution in which cellulose acetate is dissolved in a solvent of cellulose acetate are mixed, or a solution in which cellulose acetate is dissolved in a solvent of cellulose acetate is directly added to the water-soluble compound and / or Alternatively, the water-dispersible compound is added and mixed, and the water-soluble compound and / or the water-dispersible compound are dispersed and contained in the spinning dope by a predetermined dispersion or stirring treatment.

Here, a dispersion machine may be used as the dispersion mixing method. For example, when a horizontal sand mill is used as the disperser, the disk peripheral speed and the bead diameter (0.8 to
(1.0 mm diameter), the bead filling rate, the staying time inside the vessel, and the like can be appropriately adjusted to allow the dispersion and mixing.

The cellulose acetate spinning dope containing the water-soluble compound and / or the water-dispersible compound which is soluble in the solvent of cellulose acetate and incompatible with cellulose acetate thus obtained is supplied to the spinning nozzle device. ,
The cellulose acetate fiber is spun by a dry spinning method in which it is discharged into a high temperature atmosphere. In addition, in order to facilitate the production of the filter plug, the total denier as the fiber bundle is appropriately set. The spinning may be performed by a wet spinning method instead of the dry spinning method.

In the spinning, as described above, the spinning stock solution uniformly dispersed may be spun as it is, but a spinning stock solution containing a water-soluble compound and / or a water-dispersible compound and a spinning stock solution without addition are added. A method in which at least the water-soluble compound and / or water-dispersible compound-added polymer appears on the fiber surface may also be used in a composite spinning method such as a fiber side-by-side type or a sheath-core type.

The shape of the fiber cross section of the monofilament at the time of spinning may be any of a circular cross section, a Y-shaped cross section, a square cross section, and the like, and it is not particularly limited, but preferably,
From the viewpoint of filtration performance as a tobacco filter, it is preferable to have a multi-lobed irregular cross section, and among them, a Y-shaped cross section is preferable from the viewpoint of process stability.

The fiber shape of the cellulose acetate fiber of the present invention may be either staple or filament, but preferably, the cellulose acetate fiber for producing the tobacco filter of the present invention has, for example, a fineness of 1
3,000 to 500,000 fibers of 10 denier are converged to form a band-shaped fiber tow having 10 to 50 crimps per 25 mm length. In order to improve the filtration performance as a tobacco filter, it is possible to reduce the denier and increase the surface area. In that case, the fine fibers having a fineness of 0.5 to 1 denier are used.

Next, a cigarette filter composed of the filter material of the present invention is manufactured by the following method. To manufacture a tobacco filter, the cellulose acetate fiber tow of the filter material is opened with a tobacco filter plug winding device, and after adding a plasticizer, it is molded into a fiber rod shape and cut into the required length. According to the above, the cigarette filter is used.

This manufacturing method will be described in more detail with reference to FIG. 1 which shows an outline of an apparatus for manufacturing a cigarette filter. First, the crimped tow 1 of the cellulose acetate fiber of the present invention, which serves as a filter member, is uniformly spread by the spreader 2, and a plasticizer such as triacetin is uniformly applied to the plasticizer applying portion 9. After that, by passing the first ring guide 4 and the second ring guide 5 by the delivery roll 3, the opened fiber tow sheet has an arc-shaped cross section, and a winding thrust called an air jet 6 is applied. After being formed into a rod shape together with the wrapping paper 7 by a tubular forming device, it is cut into a predetermined length by a cutter 8 to form a filter plug 10.

Alternatively, using a non-woven sheet made of short fibers obtained by cutting the fiber tow into 1 to 100 mm, as shown in FIG.
It is also possible to form a rod shape with the same device as in. Further, in the plug winder, the opened fiber tow or the non-woven fabric sheet consisting of short fibers is pressure-molded by a corrugated thermoforming device having a grooved heating roll, and corrugated, after adding a plasticizer if necessary. It can also be used as a sheet.

The plasticizer used when molding this filter plug may be any plasticizer that can be applied to the cellulose acetate fiber tow. Specifically, triacetin,
A polyol ester compound such as 1,3-butylene glycol diacetate is used. The amount of the plasticizer added is 3 to 10% by weight based on the weight of the fiber tow.

When used as an actual filter, the above-mentioned rod-shaped molded product is combined with a conventional rod-shaped molded product made of cellulose acetate fiber, and the structure of the sheath filter and the core filter as shown in FIG. 2 is obtained. A filter having a different sheath core structure or a filter having a dual structure in which the structure of the filter at the mouth end portion and the structure of the filter connected to the tobacco leaf portion as shown in FIG.

In some cases, (a) to (4) of FIG.
As shown in (b), the filter may have a dual structure in which the filter (filter element B) having the sheath core structure and the plain filter (filter element A) are combined. Furthermore, as shown in (c) to (f) of FIG. 4, activated carbon or the like can be added to the filter.
The filter material of the present invention may be used in any of the sheath portion, the core portion, and the plain portion, but it is expected that the use of the filter material in the portion exposed to the external environment will promote the degradability more. As described above, even when the filter material of the ordinary cellulose acetate fiber is combined with the filter material of the present invention, the degradability of the entire filter is increased, and the degradability of the ordinary cellulose acetate filter material part can be expected to be increased.

The tobacco filter molded in this manner has a suction resistance of 100 to 100 from the viewpoint of ease of sucking and filtering performance.
The range is preferably 200 mmH ₂ O.

[0046]

The present invention will be described below in more detail with reference to examples. Table 1 shows the results of determining the solubility of the compound to be added in acetone, which is the spinning solvent, and water. In Table 1, ∘ indicates that it is soluble at 20 ° C, Δ indicates that it is soluble at 65 ° C, and x indicates that it is insoluble. In addition, Table 2 shows the results of determining whether or not the compound that was soluble in acetone was incompatible with cellulose acetate.
Determination of incompatibility with cellulose acetate, the film made by casting the acetone solution of cellulose acetate added compound into a glass plate, using an optical microscope and electron microscope, the phase separation of the added compound It was performed by observing the presence or absence. In Table 2, ∘ indicates that phase separation was observed, and × indicates that phase separation was not observed, indicating a homogeneous phase.

[0047]

[Table 1]

[0048]

[Table 2]

Example 1 A solution of cellulose acetate having an average acetylation degree of 55.5% in acetone was added to a solution having a molecular weight of 1
20,000 hydroxypropyl lulose was dissolved in acetone and mixed so that the amount of hydroxypropyl cellulose added was 20% by weight, and the cellulose acetate concentration was 2
A 7.0 wt% spinning dope was prepared. This spinning solution was dry-spun with a spinning nozzle having a hole diameter of 36 μm and 17 holes to obtain 6
A cellulose acetate fiber yarn of 5 denier / 17 filaments was obtained. Table 3 shows the strength and elongation of the obtained yarn, the strength and elongation after immersion in water for 2 weeks, and the weight reduction rate. The weight reduction rate was obtained from the fiber weight before and after immersion in water.

(Comparative Example 1) Cellulose containing no hydroxypropyl cellulose prepared in Example 1 by dissolving cellulose acetate having an average acetylation degree of 55.5% in acetone in place of the spinning dope containing hydroxypropyl cellulose. A cellulose acetate fiber yarn of 65 denier / 17 filaments was obtained in the same manner as in Example 1 except that a spinning dope having an acetate concentration of 28.85% by weight was used. Table 3 shows the strength and elongation of the obtained yarn, the strength and elongation after immersion in water for 2 weeks, and the weight reduction rate.

[0051]

[Table 3]

(Example 2) A solution of cellulose acetate having an average degree of acetylation of 55.5% in acetone was dissolved in a solution of hydroxypropyl cellulose having a molecular weight of 10,000 in acetone, and the addition amount of hydroxypropyl cellulose was 20. Mixing was carried out so that it might become a weight%, and the spinning dope of cellulose acetate concentration 27.0 weight% was prepared. Using this spinning solution, a cellulose acetate fiber tow having a single fiber fineness of 4 denier and a total fineness of 40,000 denier was obtained by a dry spinning method. The tow was crimped through a crimper to obtain a tow for cigarette filter. Table 4 shows the strength of the obtained tow and the strength after soaking in water for 2 weeks and the weight reduction rate.

(Comparative Example 2) Cellulose containing no hydroxypropyl cellulose prepared in Example 2 by dissolving cellulose acetate having an average acetylation degree of 55.5% in acetone in place of the spinning dope containing hydroxypropyl cellulose. A tow for a cigarette filter was obtained in the same manner as in Example 1 except that a spinning dope having an acetate concentration of 28.85% by weight was used. Table 4 shows the strength of the obtained tow and the strength after soaking in water for 2 weeks and the weight reduction rate.

[0054]

[Table 4]

Example 3 A solution of cellulose acetate having an average degree of acetylation of 55.5% dissolved in acetone and a solution of polyethylene glycol having a molecular weight of 600 dissolved in acetone were added, and the amount of polyethylene glycol added was 20% by weight. And mixed to give a cellulose acetate concentration of 27.0
A spinning dope of weight% was prepared. This spinning solution was added with a pore size of 36
Dry spinning was performed with a spinning nozzle having a diameter of 17 μm and a number of holes of 17 to obtain cellulose acetate fiber yarn of 65 denier / 17 filaments. Table 5 shows the strength and elongation of the obtained yarn, the strength and elongation after immersion in water for 2 weeks, and the weight reduction rate.

[0056]

[Table 5]

Example 4 A solution of cellulose acetate having an average degree of acetylation of 55.5% dissolved in acetone and a solution of polyethylene glycol having a molecular weight of 1,000 dissolved in acetone were added, and the amount of polyethylene glycol added was 20% by weight. % So that the cellulose acetate concentration is 2
A 7.0 wt% spinning dope was prepared. Using this spinning solution, a cellulose acetate fiber tow having a single fiber fineness of 4 denier and a total fineness of 40,000 denier was obtained by a dry spinning method. The tow was crimped through a crimper to obtain a tow for cigarette filter. Table 6 shows the strength of the obtained tow and the strength after soaking in water for 2 weeks and the weight reduction rate.

[0058]

[Table 6]

(Example 5) The cellulose acetate fiber yarns obtained in Example 1, Example 3 and Comparative Example 1 were bundled in a predetermined weight and stored in a fine mesh polypropylene net to constantly inflow fresh seawater. The weight reduction rate of each fiber after immersion in a water tank and immersion in seawater for 2 months is shown in Table 7. The weight reduction rate was obtained from the fiber weight before and after the immersion in seawater.

[0060]

[Table 7]

[0061]

INDUSTRIAL APPLICABILITY The filter material of the present invention and the tobacco filter of the present invention using this filter material are likely to have their shape collapsed in the presence of water. It has an easily decomposable property that disintegrates the shape of the rod of the tobacco filter in an atmosphere containing a large amount of water, water, etc., and promotes transition to a state in which it is easily decomposed by microorganisms. Furthermore, the filter material of the present invention and the tobacco filter using the same are useful as measures against environmental pollution.

[Brief description of the drawings]

FIG. 1 is a schematic view of an apparatus for producing a cigarette filter using the filter material of the present invention.

FIG. 2 is a schematic perspective view of an example of a tobacco filter manufactured using the filter material of the present invention.

FIG. 3 is a schematic perspective view of another example of a cigarette filter manufactured using the filter material of the present invention.

FIG. 4 is a vertical cross-sectional view of examples (a) to (f) of tobacco filters manufactured using the filter material of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Cellulose acetate fiber tow 2 Opening device 3 Delivery roll 4 Ring guide 5 Ring guide 6 Air jet 7 Wrapping paper 8 Cutter 9 Plasticizer impregnation part 10 Filter plug 11 Filter material of the present invention 12 Filter material made of ordinary cellulose acetate fiber 21 core part of filter element (B) 22 sheath part of filter element (B) 23 wrapping paper 24 ventilation holes 25 filter part of filter element (A) 26 wrapping paper 57 cigarette cylinder part 58 activated carbon

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[Procedure amendment]

[Submission date] October 14, 1996

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0049

[Correction method] Change

[Correction contents]

Example 1 A solution of cellulose acetate having an average acetylation degree of 55.5% in acetone was added to a solution having a molecular weight of 1
Dissolve 10,000 hydroxypropyl cellulose in acetone and add 20% hydroxypropyl cellulose.
Mixing was carried out so that it might become a weight%, and the spinning dope of cellulose acetate concentration 27.0 weight% was prepared. This spinning dope was dry-spun with a spinning nozzle having a hole diameter of 36 μm and 17 holes to obtain a cellulose acetate fiber yarn of 65 denier / 17 filaments. Table 3 shows the strength and elongation of the obtained yarn, the strength and elongation after immersion in water for 2 weeks, and the weight reduction rate. The weight reduction rate was obtained from the fiber weight before and after immersion in water.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0055

[Correction method] Change

[Correction contents]

Example 3 A solution of cellulose acetate having an average degree of acetylation of 55.5% dissolved in acetone and a solution of polyethylene glycol having a molecular weight of 600 dissolved in acetone are added to the solution in which the amount of polyethylene glycol is 20% by weight. So that the cellulose acetate concentration is 27.0
A spinning dope of weight% was prepared. This spinning solution was added with a pore size of 36
Dry spinning was performed with a spinning nozzle having a diameter of 17 μm and a number of holes of 17 to obtain cellulose acetate fiber yarn of 65 denier / 17 filaments. Table 5 shows the strength and elongation of the obtained yarn, the strength and elongation after immersion in water for 2 weeks, and the weight reduction rate.

[Procedure 3]

[Document name to be amended] Statement

[Name of item to be corrected] 0057

[Correction method] Change

[Correction contents]

Example 4 A solution of cellulose acetate having an average degree of acetylation of 55.5% in acetone was dissolved in a solution of polyethylene glycol having a molecular weight of 1,000 in acetone, and the amount of polyethylene glycol added was 20% by weight. Mix to give a cellulose acetate concentration of 2
A 7.0 wt% spinning dope was prepared. Using this spinning solution, a cellulose acetate fiber tow having a single fiber fineness of 4 denier and a total fineness of 40,000 denier was obtained by a dry spinning method. The tow was crimped through a crimper to obtain a tow for cigarette filter. Table 6 shows the strength of the obtained tow and the strength after soaking in water for 2 weeks and the weight reduction rate.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location D01F 1/02 D01F 1/02 2/30 2/30 (72) Inventor Atsushi Tsuneda Yokohama City, Kanagawa Prefecture 6-2 Umegaoka, Aoba-ku, Tobacco Central Research Institute, Tobacco Inc. (72) Inventor Tetsuro Shibata 6-2 Umegaoka, Aoba-ku, Yokohama, Kanagawa Tobacco Research Center, Tobacco Inc. (72) Inventor, Yoichiro Yamashita 2nd day, 6 Umegaoka, Aoba-ku, Yokohama-shi, Kanagawa Tobacco Central Research Institute

Claims (3)

[Claims] 1. A cellulose acetate soluble in a solvent,
A filter material comprising a cellulose acetate fiber tow containing 5 to 50% by weight of a water-soluble compound and / or a water-dispersible compound which is incompatible with cellulose acetate. 2. The filter material according to claim 1, wherein the water-soluble compound and / or the water-dispersible compound is at least one selected from the group consisting of hydroxyalkyl cellulose, polyalkylene glycol, glycerin fatty acid ester and alkylene glycol fatty acid ester. 3. A cigarette filter comprising the filter material according to claim 1 or 2.