JPS6355521B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical field The present invention relates to the use of a fabric or sheet-like swellable carboxyalkyl cellulose (for example, a sodium salt of carboxyalkyl cellulose) as a fabric or sheet-like product containing cellulose fibers ( below,
(abbreviated as "fabric material").

(b) Prior Art Swellable carboxyalkylcellulose has excellent properties as an absorber for physiological fluids such as urine, blood, sweat, etc., and has recently been used particularly in absorbent bands for sanitary napkins, absorbent pads for disposable diapers, and hospitals. Applications are expanding to underpads, etc.

As a swellable carboxyalkyl cellulose,
Swellable carboxyethyl cellulose (hereinafter referred to as
CEC (abbreviated as "CEC") and swellable carboxymethyl cellulose (hereinafter abbreviated as "CMC") are known, but CMC is generally used for the above purposes because it is inexpensive and has excellent absorption properties.

However, in conventional absorbent bands and absorbent pads using CMC, since CMC is powder, granular, or short fiber, in order to use it for the above-mentioned purpose, the product is made by scattering it on other nonwoven fabrics and conjugating them thereto. Therefore, no matter how high the absorption capacity of these absorbers is, when combined with other nonwoven fabrics with low absorption capacity, the absorption capacity becomes relatively small. In addition, in order to overcome this problem, even if a large amount of absorbent material is combined with other nonwoven fabrics, powders and granules may fall out of the nonwoven fabric, and the absorption capacity may vary depending on the degree of uniformity of dispersion. Therefore, it is virtually impossible to conjugate a large amount of absorbent material. There are also absorbent materials made into paper using short fibers, but the tensile strength, flexibility,
There are problems with texture, ease of handling, etc.

(c) Object of the invention The object of the present invention is to provide an industrially advantageous method for producing high-quality swellable carboxyalkylcellulose in the form of a fabric or sheet, which is useful as an absorbent material, from a fabric containing cellulose fibers. is to provide.

(d) Structure of the Invention The carboxyalkylation etherification method according to the present invention involves the production of swellable carboxyalkylcellulose by reacting cellulose with a carboxyalkylation etherification agent in an aqueous alkaline medium. In the alkalization and etherification reaction process of the fabric or sheet-like material contained, a closed container equipped with a cylinder in the center having a large number of holes around the circumference is used, and a chemical solution is introduced into the container from outside the container, Using a liquid circulation system in which the medicinal liquid is ejected from the inside of the cylinder to the outside or from the outside to the inside, the medicinal liquid flows out of the container, and the fabric-like material or sheet-like material is wrapped around the cylinder and filled into the container. It is characterized by carrying out a reaction by pressurizing and circulating a chemical solution, and after the reaction, the cylinder is rotated at high speed to remove the liquid.

Furthermore, in the carboxyalkylation etherification method of the present invention, after deliquing as described above,
To neutralize the product, the deliquified chemical solution is collected outside the container, and a separately prepared methanol-water solution is circulated and ejected into the container to remove the liquid, and the deliquified solution is transferred to the container. It is characterized in that it is neutralized outside, the neutralized solution is circulated and ejected into the container to remove liquid again, and this operation is repeated to neutralize the product.

Furthermore, the carboxyalkylation etherification method of the present invention is characterized by washing with a methanol-water based washing solution after neutralization as described above.

Furthermore, the carboxyalkylation etherification method of the present invention is characterized in that after washing as described above, air is forced into the container and dried.

(E) Embodiment The aqueous alkaline medium used in the present invention is preferably an isopropanol-based aqueous alkaline mixed solvent, particularly preferably a mixed solvent consisting of isopropanol, water-methanol and caustic soda. As the etherification agent, monochloroacetic acid or a salt thereof is preferably used, and this etherification agent is used in addition to the above solvent.

Fabrics containing cellulose fibers include:
Preferably, woven and nonwoven fabrics containing cotton and woven and nonwoven fabrics containing recycled fibers are used. As the cellulose fibers constituting the woven fabric and nonwoven fabric, any combination of cotton alone, cotton blend, rayon alone, and rayon blend may be used.

In the process of the invention, the carboxyalkylation etherification of the fabric containing cellulose fibers is carried out using special equipment. That is, a sealed container is used, which has a cylinder in the center with a large number of holes around the circumference, the fabric-like material is wound around the cylinder in the form of a roll and stored in the sealed container, and the mixed solvent, that is, the chemical solution is poured into the container from the outside. The chemical liquid is introduced into the cylinder and ejected from the inside to the outside or from the outside to the inside through the numerous holes, and then flows out of the container. A device is used that is configured to rotate the cylinder at high speed to remove liquid. By using the apparatus configured in this way, the carboxyalkylation reaction of the fabric can be made uniform, and high-quality fabric-like or sheet-like swellable carboxyalkyl cellulose can be industrially advantageously produced. .

Hereinafter, the method of the present invention will be explained in detail based on an illustrated example. FIG. 1 is a cross-sectional explanatory diagram showing an example of an apparatus for carrying out the method of the present invention. In the figure, a cylinder 2 having a large number of holes 3 around its circumference is provided at the center of the interior of a cylindrical closed container 1, which also serves as a rotating shaft. The cylinder 2 is detachably attached within the container 1. A cylindrical basket 4 surrounding the cylinder 2 is provided within the container 1, and the bottom portion 22 of the basket is fixed to a rotating shaft 5.
A chemical solution introduction tube 6 is inserted into the rotating shaft 5.
This connecting portion is formed into an oil seal type rotating structure. A rotating pulley 7 is attached to the rotating shaft 5, and the rotating pulleys 9 of the electric motor 8 are connected by a belt 10. In addition, the upper end 11 of the cylinder 2
is rotatable and sealed. The container 1 is also provided with an outflow pipe 12 for the reaction solvent and an exhaust pipe 13 for drying air. The outflow pipe 12 is connected to a reaction solvent tank 14, and in this solvent tank 14, reaction solvent components such as isopropanol (hereinafter referred to as "i-PA"), water, and methanol (hereinafter referred to as "MeOH") are collected. ), caustic soda (hereinafter referred to as "NaOH") as an alkalizing agent, and monochloroacetic acid (hereinafter referred to as "MCA") as an etherifying agent are indicated by arrow 1.
5 to prepare an etherification reaction treatment solution.

The composition of the reaction solvent is basically i-PA45~80
Volume%, MeOH 10-30% by volume, Water 10-25% by volume
The composition is effective. As the i-PA concentration increases, the effective utilization rate of MCA (the amount of MCA that participates in the reaction with cellulose) increases, but unevenness in the degree of substitution between the layers of the rolled fabric becomes more likely to occur. . Therefore, it is necessary to select the optimum value depending on the fabric.

The adjusted reaction solvent is pressurized into the closed container 1 through the introduction pipe 6 through the liquid supply pipe 19 equipped with a liquid supply pump 16 and an on-off valve 20 . Arrow 17 indicates the introduction of heating steam. Further, arrow 18 indicates the press-in of drying air. The reaction solvent pressurized into the closed container 1 is ejected from the hole 3 of the cylinder 2 and flows through the outflow pipe 12 to the liquid sending pipe 1.
9 and is returned to the reaction solvent tank 14. Thus, the apparatus for carrying out the method of the invention is configured in a liquid circulation system.

When operating the device, first, the cylinder 2 is removed from the closed container 1, the fabric or sheet material to be treated is wound around the outer circumference of the cylinder 2 to form a roll, and this is placed and filled into the basket 4 of the closed container 1. do. Next, i-PA, water and
Add MeOH to adjust the reaction solvent, send the liquid,
The liquid is press-fitted into the closed container 1, ejected from the hole 3 of the cylinder 2, and penetrated into a roll-like fabric or a tray-like material to be sufficiently permeated. After that, the outflow pipe 12
The solvent is sent out and returned to the reaction solvent tank 14. At this time, by rotating the cylinder 2, the centrifugal force caused by the rotation allows the reaction solvent to penetrate uniformly into the fabric or sheet. Note that heated steam 17 is introduced to adjust the temperature of the reaction solvent.

Next, NaOH is added to the reaction solvent in the reaction solvent tank 14 to prepare an aqueous alkaline medium. This reaction solvent is then circulated in the same manner as described above. NaOH present in the solvent comes into contact with the fabric in the container 1 together with the solvent and reacts with the cellulose. In this way, an alkali cellulose-forming reaction of cellulose occurs, and the cellulose in the fabric becomes alkali cellulose. The chemical reaction formula is as follows.

Cell-OH+NaOH→Cell-Na+H ₂ O As is well known, this reaction occurs over a wide temperature range. When carboxyalkylation is carried out with MCA,
It is desirable to carry out the heating within the range of 30°C to 80°C. The amount of NaOH to be added depends on the degree of substitution in the etherification reaction and cannot be determined unconditionally. Reaction time is usually 10-15 minutes.

Subsequently, MCA is added into the reaction solvent and the solution is circulated. The required amount of MCA must be added evenly over a certain period of time, so that excess MCA does not come into contact with the alkali cellulose-treated fabric at one time. If an excessive amount of MCA comes into contact with the MCA at one time, unevenness in the degree of etherification will occur between the roll-shaped layers wound around the cylinder 2.

After the etherification reaction is completed, the forced circulation of the reaction solvent by the pump 16 is stopped. container 1
A head is provided between the container 1 and the reaction solvent tank 14.
The reaction solvent is transferred to the reaction solvent tank 14 due to this head difference.
is naturally refluxed. However, the roll-shaped fabric contains a large amount of reaction solvent. In order to remove the reaction solvent contained in the fabric, the cylinder 2 is rotated at high speed (usually 500 to 1500 rpm) to shake off the reaction solvent using centrifugal force. Then, the deliquified reaction solvent is collected outside the container, that is, from the collection pipe 21 into another container.

After the etherification reaction is completed and the liquid is removed, the fabric still contains the reaction solvent itself, unreacted NaOH, NaCl from the reaction product, and other side reactants (e.g., sodium monochloroacetate, sodium methoxyacetate) between the constituent fibers. etc.). These substances must be removed in order to turn the produced etherified product into a product. To do this, first neutralize unreacted NaOH, then use a washing solution to
It is desirable to remove NaCl and other side reactants.

First, the neutralization step of unreacted NaOH will be described. As a neutralizing agent, acetic acid and hydrochloric acid (hereinafter referred to as
(labeled “HCl”) is used. Sulfuric acid is not preferred.

Prepare a MeOH-aqueous solution in a reaction solvent tank,
This is introduced into the container 1 and spouted out, and then the cylinder 2 is rotated to remove the liquid, and the deliquid solution is returned to the outside of the container, that is, to the reaction solvent tank, where it is neutralized using HCl, Circulating the solution again - Spraying - Deliquing -
Neutralization is completed by repeating reflux-neutralization-circulation.

This neutralization method is the key point of the method of the present invention, and was made possible for the first time by an apparatus configured to rotate the cylinder 2.

The chemical structure of the reaction product is Cell−
OCH ₂ COONa is in the Na form, and it is well known that it has absorption ability only when it exists in this Na form. However, in the neutralization step, acidic solutions (e.g. HCl)
When it comes into contact with the reaction product, Na ⁺ and H ⁺ immediately switch places and become H-type. The chemical reaction formula is as follows.

Cell-OCH ₂ COONa+H ⁺ Cl ^- → Cell-OCH ₂ COOH+NaCl This structure has no absorption capacity at all and loses the high absorption capacity that is the object of the invention. Therefore,
The conventional method was to wash the product exclusively with alcohol to remove alkaline content and neutralize the product, without neutralizing with acid. However, this method is economically expensive and requires a long time for washing, which is extremely disadvantageous from an economical and industrial standpoint.

As in the present invention, the circulating reaction solvent is neutralized with a neutralizing agent, the neutral solvent is again brought into contact with the reaction product as a product to elute the alkaline content in the product, and the alkaline solvent is again deliquified. Neutralize with a neutralizing agent. If this method is repeated, the neutralizing agent will never come into contact with the product, so the Na type will never change to the H type, and the absorption capacity will not be impaired.

The intended purpose is thus achieved in a very economical manner. According to the examples described later, complete neutralization could be achieved by repeating the neutralization twice.

The product is then washed. Water as a cleaning solution
MeOH type is preferable. In water itself, the carboxyalkylated fabric absorbs water, swells and dissolves. High solubility of NaCl and other substances;
Furthermore, as a result of extensive research into economical cleaning agents, one with a MeOH concentration in the range of 55 to 100% (volume %) is suitable. When the MeOH concentration is less than 55%, as the water concentration increases, the carboxyalkylated fabric rapidly absorbs water, swells, and eventually dissolves.

When washing the product, the washing effect can be improved by removing liquid by rotating the cylinder.

After washing and dehydrating, the product is dried with dehumidified room temperature air or heated air to form a product.

In the above explanation, an example was given in which the reaction solvent is forced into the inside of the cylinder 2 and ejected toward the outer fabric or sheet-like object, but as another example, the reaction solvent is forced into the outside of the cylinder 2 and the treatment is performed. It can also be carried out by squirting it inside the cylinder 2 through a cloth or sheet-like material.

As described above in detail, according to the method of the present invention, carboxyalkylation and etherification of fabrics or sheets can be carried out rationally and industrially advantageously, and high quality products can be uniformly treated. Fabric-like or sheet-like swellable carboxyalkylated cellulose can be produced.

(f) Examples Hereinafter, the method of the present invention will be specifically explained using examples.

Example 1 A nonwoven fabric made of recycled cellulose was subjected to a reaction. The nonwoven fabric is a porous nonwoven fabric formed from continuous filaments of copper ammonia rayon disclosed in Japanese Patent Publication No. 52-6381, and has a single yarn of 3 denier and a basis weight of 30 g/m ^{2 .}
I used the one from

25 kg of this nonwoven fabric was wound in a roll around the cylinder 2 of the apparatus shown in FIG. 1, and was installed in the apparatus. Next, a reaction solvent was prepared in the reaction solvent tank. That is i-PA70V
% (means “capacity%”. The same applies hereinafter),
It consisted of 16V% MeOH and 14V% water, and the total amount was adjusted to 200℃, and the temperature was adjusted to 60℃.

Next, this reaction solvent was pumped by a liquid pump and ejected from a number of holes in the cylinder to permeate the nonwoven fabric, and then the reaction solvent was returned and circulated. After 1 minute, add NaOH to the reaction solvent tank and
The concentration was adjusted to 6.0W% (weight%). This reaction solvent was then circulated for 20 minutes. Subsequently, MCA was poured into the reaction solvent tank and circulated, and the concentration of MCA was finally adjusted to 6.0 W%. During this time, the cylinder was rotated to ensure uniform penetration of the solvent. The reaction time for etherification was approximately 90 minutes.

After the reaction was completed in this way, neutralization was carried out. That is, first, the cylinder was rotated at high speed to remove liquid, and the removed solvent was collected in another container. Thereafter, an 84V% MeOH solution was prepared in the reaction solvent tank, and this was pumped into the container and ejected. The alkaline solvent is then deliquified and sent to the reaction solvent tank, where it is used as a neutralizing agent at a concentration of
15W% HCl was added to neutralize. Then, this neutralized alkaline solvent was pumped and spouted, and the liquid was removed again, and the solvent was returned. Neutralization and pumping were performed to complete the neutralization. In this example, complete neutralization was achieved by repeating the neutralization twice.

Next, 84V% MeOH was used as a washing solution, and this was circulated for thorough washing.

After washing, the liquid was removed, and room temperature air was sent to dry the nonwoven fabric.

The characteristics of the CMC nonwoven fabric manufactured in this way are: basis weight 30 g/m ² , thickness 0.29 mm, *Tensile strength (longitudinal direction) 7 (g/cm)/(g/cm ² ), * *
Flexibility (vertical direction) 26mm, water absorption rate of distilled water
40 times, 1% saline absorption magnification 45 times, substitution degree DS
=0.35.

These values indicate that both tensile strength and flexibility are almost unchanged from before treatment.

Moreover, the absorption capacity of 1% saline shows a value sufficient for use in blood absorption and urine absorption.

*Measurement of tensile strength (g/cm)/(g/cm ² )
Tensilon/UTM−4−100TOYO
Tensile strength using BALDWIN Co, LTD
It was run at 15cm/min.

※※Flexibility was measured in accordance with the 45° cassotile lever method of JIS-L-1005.

※※※The absorption capacity was measured as follows. Under standard conditions, cut a 250 x 150 mm sample from the product, accurately measure its weight, and
Place it on an 80 mesh wire mesh, drop distilled water or 1% NaCl water onto it, and leave it for 10 minutes after supersaturation. After that, wipe off the excess water with paper,
Measure the weight and calculate the absorption capacity using the following formula.

Absorption capacity = weight of sample after absorption - weight of sample / weight of sample Example 2 25 kg of cotton gauze was treated using the same equipment used in Example 1 and with the same concentration and amount of reaction solvent. , produced CMC-modified gauze.

The obtained CMC-treated gauze had a 1% NaCl water absorption capacity of 39 times.

Example 3 A paper-like nonwoven fabric disclosed in Japanese Unexamined Patent Publication No. 48-68866 was subjected to CMC. This nonwoven fabric is made of copper ammonia cellulose fibers and has a basis weight of 30 g/m ² . Since it has a paper-like appearance, a large number of small holes were punched by needle punching to facilitate the reaction.

2.5 kg of this nonwoven fabric was packed into the apparatus used in Example 1, and treated using the same reaction solvent and the same concentration as used in Example 1 to produce a CMC paper-like nonwoven fabric.

The CMC paper-like nonwoven fabric obtained had a 1% NaCl water absorption capacity of 36 times.

Example 4 A nonwoven fabric was produced using ordinary short rayon fibers and subjected to a reaction. The short fibers were introduced into a fibrillation and dispersion device to be dispersed, and deposited on a net conveyor to form a sheet. This was introduced into a treatment device using a water jet. This device consists of 2 rows of 15 nozzles, and is configured to spray waterjet from the nozzles in the form of needles to firmly intertwine short fibers to produce a nonwoven fabric. Area weight: 35g/ ^m2
The sheet was passed through a device and treated with a water pressure of 40 kg/cm ² to obtain a nonwoven fabric in which the fibers were tightly intertwined and a structure was formed.

25 kg of this nonwoven fabric was treated using the same equipment used in Example 1, and with the same concentration and amount of reaction solvent, to produce a CMC nonwoven fabric. obtained
The absorption capacity of 1% NaCl water of CMC nonwoven fabric is
It showed 43 times.

Example 5 Polypropylene short fibers were blended with ordinary short rayon fibers as an adhesive and thermally bonded to produce a nonwoven fabric, which was subjected to a reaction. A blend of 80% rayon short fibers and 20% polypropylene short fibers was introduced into a fibrillation and dispersion device for dispersion, and deposited on a net conveyor to form a sheet. Subsequently, this sheet was introduced into a heat setting roller device and heat set to obtain a nonwoven fabric. This non-woven fabric is formed to have a basis weight of 35g/ ^m2 and a thickness of
It was formed to 0.15mm.

25 kg of this nonwoven fabric was treated using the same equipment used in Example 1, and with the same concentration and amount of reaction solvent, to produce a CMC nonwoven fabric. obtained
The absorption capacity of 1% NaCl water of CMC nonwoven fabric is
It showed 32 times.

Example 6 Bemberg taffeta (50 d long/60 d latitude) was subjected to a reaction. Using the same equipment used in Example 1, 12 kg of Bemberg taffeta was set in the equipment, and the concentration and amount of the reaction solvent were kept the same as in Example 1. At this time, in order to increase the effect of the solvent penetrating the Bemberg taffeta, we increased the pressure of the solvent and increased the rotation of the cylinder.

Obtained CMC Bemberg Taffeta 1
%NaCl water absorption capacity was 32 times.

Example 7 Taffeta made from a mixture of Bemberg and polyester (warp polyester 50d, 50%/weft Bemberg 75d,
50%) was subjected to the reaction. The reaction was carried out according to Example 6. 1% of the obtained CMC fabric
The absorption capacity of NaCl water was 20 times.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional explanatory diagram showing an example of an apparatus for carrying out the method of the present invention. 1...Cylindrical airtight container, 2...Cylindrical, 3...
Hole, 4... Cylindrical basket, 6... Reaction solvent introduction pipe, 7... Rotating pulley, 8... Electric motor, 1
0...Belt, 14...Reaction solvent tank, 16...Liquid pump.

Claims (1)

[Scope of Claims] 1. In producing swellable carboxyalkylcellulose by reacting cellulose and a carboxyalkylated etherification agent in an aqueous alkaline medium, a fabric or sheet containing cellulose fibers is treated with alkali. In the chemical and etherification reaction steps, a closed container equipped with a cylinder in the center having a large number of holes around the circumference is used, a chemical solution is introduced into the container from outside the container, and the chemical solution is transferred from the inside of the cylinder to the outside or Using a liquid circulation system in which the chemical liquid is ejected from the outside into the inside and then flows out of the container, the fabric-like material or sheet-like material is wrapped around a cylinder and filled into the container, and the chemical liquid is press-in and circulated to perform a reaction, A swelling carboxyalkylation etherification method characterized by rotating a cylinder at high speed to remove liquid after the reaction. 2. The method according to claim 1, wherein the etherification is carboxymethylation with monochloroacetic acid or a salt thereof. 3. The method according to claim 1, wherein the fabric or sheet containing cellulose fibers is selected from woven and nonwoven fabrics containing cotton and woven and nonwoven fabrics containing recycled fibers. 4. In producing swellable carboxyalkylcellulose by reacting cellulose and a carboxyalkylated etherifying agent in an aqueous alkaline medium, alkalization and etherification reaction steps of a fabric or sheet containing cellulose fibers. In this method, a closed container is equipped with a cylinder in the center having a large number of holes around the circumference, a medicinal solution is introduced into the container from outside the container, and the medicinal solution is ejected from the inside of the cylinder to the outside or from the outside to the inside. After that, using a liquid circulation system in which the chemical solution flows out of the container, the fabric or sheet-like material is wrapped around a cylinder and filled into the container, and the chemical solution is pressurized and circulated to perform a reaction. After the reaction, the cylinder is moved at high speed. Rotating to remove liquid and subsequently neutralizing the product, collecting the deliquified chemical solution out of the container,
A separately prepared methanol-water solution is circulated inside the container and squirted to remove liquid, the deliquified solution is neutralized outside the container, and the neutralized solution is circulated and squirted into the container to remove liquid again. and repeating this operation to neutralize the product. 5. The method according to claim 4, wherein the etherification is swelling carboxymethylation with monochloroacetic acid or a salt thereof. 6. The method according to claim 4, wherein the fabric or sheet containing cellulose fibers is selected from woven and nonwoven fabrics containing cotton and woven and nonwoven fabrics containing recycled fibers. 7. Alkalization and etherification reaction step of a fabric or sheet containing cellulose fibers in producing swellable carboxyalkylcellulose by reacting cellulose and a carboxyalkylated etherification agent in an aqueous alkaline medium. In this method, a closed container is equipped with a cylinder in the center having a large number of holes around the circumference, a medicinal solution is introduced into the container from outside the container, and the medicinal solution is ejected from the inside of the cylinder to the outside or from the outside to the inside. After that, using a liquid circulation system in which the chemical solution flows out of the container, the fabric or sheet-like material is wrapped around a cylinder and filled into the container, and the chemical solution is pressurized and circulated to perform a reaction. After the reaction, the cylinder is moved at high speed. Rotating to remove liquid and subsequently neutralizing the product, collecting the deliquified chemical solution out of the container,
A separately prepared methanol-water solution is circulated inside the container and squirted to remove liquid, the deliquified solution is neutralized outside the container, and the neutralized solution is circulated and squirted into the container to remove liquid again. and repeating this operation to neutralize the product, followed by washing with a methanol-water based washing solution. 8. The method according to claim 7, wherein the etherification is swelling carboxymethylation with monochloroacetic acid or a salt thereof. 9. The method according to claim 7, wherein the fabric or sheet containing cellulose fibers is selected from woven and nonwoven fabrics containing cotton, and woven and nonwoven fabrics containing recycled fibers. 10. The method according to claim 7, wherein the methanol concentration (volume %) in the methanol-water cleaning solution is in the range of 55% to 100%. 11 In producing swellable carboxyalkylcellulose by reacting cellulose and a carboxyalkylated etherifying agent in an aqueous alkaline medium, alkalization and etherification reaction steps of a fabric or sheet containing cellulose fibers In this method, a closed container is equipped with a cylinder in the center having a large number of holes around the circumference, a medicinal solution is introduced into the container from outside the container, and the medicinal solution is ejected from the inside of the cylinder to the outside or from the outside to the inside. After
Using a liquid circulation system in which the chemical liquid flows out of the container, the fabric or sheet-like material is wrapped around a cylinder and filled into the container, the chemical liquid is pressurized and circulated to perform the reaction, and after the reaction, the cylinder is rotated at high speed. When deliquifying and subsequently neutralizing the product, the deliquified chemical solution is collected outside the container, and a separately prepared methanol-water solution is circulated and spouted into the container to deliquify it. The drained solution is neutralized outside the container, and the neutralized solution is circulated and ejected into the container to remove the liquid again. This operation is repeated to neutralize the product, and then washed with a methanol-water based cleaning solution. and then drying by pressurizing air into the container. 12. The method according to claim 11, wherein the etherification is carboxymethylation with monochloroacetic acid or a salt thereof. 13. The method according to claim 11, wherein the fabric or sheet containing cellulose fibers is selected from woven and nonwoven fabrics containing cotton and woven and nonwoven fabrics containing recycled fibers. 14. The method according to claim 11, wherein the methanol concentration (volume %) in the methanol-water cleaning solution is in the range of 55% to 100%.