JP3111584B2 - Method for producing spherical cellulose fine particles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing fine spherical cellulose fine particles. To elaborate further,
The present invention relates to a method for producing spherical cellulose fine particles comprising regenerated cellulose and having a smaller particle size than conventional ones.

[0002]

2. Description of the Related Art Granules of cellulose or various derivatives thereof have been widely used in various fields such as chromatography materials such as ion exchange and affinity, polymer carriers, cosmetic additives and lubricants.

Conventionally, as a method for producing cellulose particles, Japanese Patent Publication No. 52-11237 discloses a method of dissolving benzoic acid or acetic acid in benzene by dropping cellulose copper solution into a benzene solution containing an emulsifier. A method of feeding into a regenerated bath is disclosed, but in this method, since the diameter of the small droplets of the cellulose copper solution is large, the particle size of the cellulose microspheres can be obtained only as large as 30 to 315 μm. .

JP-A-61-241337 discloses that a viscose solution and a water-soluble anionic polymer compound are mixed and stirred, and the viscose is coagulated into fine particles at a temperature of 70 ° C. Neutralize with acid and regenerate 20μ
A method for producing spherical or long spherical microcellulose particles having an average particle diameter of not more than m is disclosed.

JP-A-48-21738 discloses that viscose having an average degree of polymerization of 400 or more is dropped in a coagulation regenerating bath having a low acid concentration and a low bow nitrate concentration to coagulate. A method for producing regenerated cellulose granules having a size of 30 to 46 mesh (300 to 590 μm) by gradually regenerating is disclosed.

Furthermore, Japanese Patent Publication No. 56-21176 discloses that viscose is extruded from a discharge port, and the extruded liquid flow is changed into a flow of liquid droplets, which are dropped into a coagulation regenerating bath as substantially spherical droplets. And 16-170 mesh (88-
A method for producing cellulose granules having a size of 1168 μm) is described.

Further, JP-B-49-89748 and JP-A-57-212231 disclose that a regenerated cellulose fibrous material or a natural cellulose fibrous material is hydrolyzed, dried and pulverized, respectively. A method for producing a cellulose powder having a length / diameter ratio of 20/1 to 2/1 and a length of 1 mm or less is disclosed.

Further, Japanese Patent Publication No. 57-45254 discloses that a viscose suspension is added to a water-insoluble liquid (for example, chlorobenzene), and the mixture is heated to a temperature of 30 to 100 ° C. while continuously stirring the mixture. A method for producing cellulose fine particles having a particle size of 150 to 350 μm and a content of 85% by volume or more by heating to solidify viscose and then dispersing the resulting particles in a water-soluble acid solution is disclosed. Have been.

In Japanese Patent Publication No. 55-39565, a methylene chloride or chloroform solution of cellulose triacetate is added dropwise with stirring to an aqueous medium in which a dispersant comprising, for example, gelatin or polyvinyl alcohol is dissolved. This is heated to form spherical particles of cellulose triacetate, which is then saponified to 30-500 μm
A method for producing cellulose spherical particles having a particle size of

Further, Japanese Patent Publication No. 55-40618 discloses a cellulose ester other than cellulose triacetate.
A method for producing cellulose particles having a particle size of 50 to 500 μm by exactly the same method as above is disclosed.

Japanese Patent Application Laid-Open No. 55-28763 discloses that a cellulose fatty acid ester is dissolved in a mixed solvent of three or more solvents having a boiling point difference of 30 ° C. or more, and this solution is spray-dried. A method for producing microspherical particles having an average particle size of 30 μm is disclosed.

Further, JP-A-57-159801 discloses that paraformaldehyde and dimethyl sulfoxide (D
MSSO), and disperse the resulting solution in a liquid that does not dissolve DMSO, for example, a liquid such as liquid paraffin. This dispersion is mixed with a coagulant for cellulose. A method for producing a spherical cellulose gel having a particle size of 50 to 500 μm by gelling and agglomerating dispersed droplets of cellulose and regenerating it with warm water as needed is disclosed.

However, a method for stably producing spherical cellulose fine particles having an average particle size of 15 μm or less and having a small variation in particle size has not been known.

[0014]

The problem to be solved by the present invention is as follows.
Particles having an average particle diameter smaller than that of the prior art, and preferably having a variation in the particle diameter from the average particle diameter in the range of ± 5 μm account for 60% (weight) or more of all the particles. An object of the present invention is to provide a method for producing spherical cellulose particles having a distribution.

[0015]

Means for Solving the Problems In the conventional cellulose granulation method, the average particle size of the obtained cellulose particles is large,
In addition, there was a problem that the range of variation of the particle size was wide, but the present inventors focused on the emulsification of cellulose, particularly the effect of miniaturization of cellulose using a water / oil type (W / O type) cellulose emulsion. However, the present inventors succeeded in producing spherical cellulose particles as small as could not be achieved by the conventional method, and completed the present invention.

In the method (I) for producing spherical cellulose fine particles of the present invention, a water / oil type viscose emulsion liquid is prepared by adding a viscose liquid and a surfactant to a dispersion medium comprising a water-immiscible liquid. And separately adding a viscose coagulation liquid to a dispersion medium comprising a water-immiscible liquid,
An oil-type viscose coagulation liquid emulsion was prepared, and these two emulsions were mixed and reacted with each other to give an average particle size of 15 μm.
m or less spherical cellulose fine particles.

In another method (II) for producing spherical cellulose fine particles of the present invention, a water / oil type viscose is prepared by adding a viscose liquid and a surfactant to a dispersion medium comprising a water-immiscible liquid. An emulsion is prepared, and an acidic gas is blown into the viscose emulsion, and the viscose emulsion is reacted with the acidic gas to form spherical cellulose fine particles having an average particle diameter of 15 μm or less.

Still another method (III) for producing spherical cellulose fine particles of the present invention comprises: dispersing a dispersion medium comprising a water-immiscible liquid in a dispersion medium comprising
A viscose emulsion of a water / oil type is prepared by adding a viscose liquid and a surfactant, and the viscose emulsion is mixed with a viscose coagulating liquid or a viscose coagulating liquid and a surfactant while stirring the viscose emulsion. , To form spherical cellulose fine particles having an average particle diameter of 15 μm or less.

[0019]

In the methods (I), (II) and (III) of the present invention,
As a dispersion medium to be used, an organic solvent immiscible with water is used. Examples of the dispersion medium which is easy to handle in consideration of flammability, boiling point, and the like include cyclohexane, n-hexane, benzene, heptane, octane, isooctane, toluene, tetradecane, and the like. However, organic solvents that can be used in the present invention. Is not limited to the above, and any solvent that does not react with the viscose liquid and the viscose coagulating liquid can be used. These organic solvents may be used alone or as a mixture.

In the methods (I), (II) and (III) of the present invention, the surfactant used in the W / O viscose emulsion is an important component for emulsifying the viscose liquid. The surfactant that can be used in the present invention is appropriately selected from a nonionic surfactant, an anionic surfactant, a cationic surfactant, and an amphoteric surfactant.

The present inventors have examined the compatibility of a dispersion medium, a viscose liquid, and a combination of a viscose coagulating liquid and a surfactant with a surface tensiometer (trade name: FACE).
CBVP-A3 type surface tensiometer, Kyowa Interface Science Co., Ltd.
As a result of various studies using the above method, it was found that it is preferable to select a surfactant so that the interfacial tension of the W / O viscose emulsion is 5 dyne / cm or less. The surfactant may be composed of a single component,
Two or more kinds of components may be mixed. In addition, a surfactant may be added to a surfactant (co-sur).
Factant) may be added.

Further, the smaller the interfacial tension of the W / O viscose emulsion, the smaller the average particle size of the spherical cellulose particles formed. This interfacial tension depends on the amount of the surfactant added and the temperature. Because it changes, W /
The particle size of the cellulose fine particles obtained can be appropriately adjusted by controlling conditions such as the type and amount of the surfactant in the O-type viscose emulsion and the temperature thereof.

A W / O viscose emulsion;
When the interfacial tension is high, the stability of the micro liquid particles in the emulsion is reduced, and the coalescence of the micro liquid particles in the emulsion occurs within a short time depending on the conditions. Sometimes. For this reason, it is preferable to sufficiently stir each emulsion and to make it react immediately after its formation. On the other hand, the conditions under which the fine liquid particles are stably emulsified in the emulsion,
For example, 10% sulfuric acid and a surfactant (trademark: Emulgen 9)
06, manufactured by Kao Corporation) 0.2 mol / kg of cyclohexane
Was added to cyclohexane, the measured value of the interfacial tension at a temperature of 25 ° C. of the emulsion obtained was 0.1 dy
ne / cm or less. In this state, the emulsion particles cannot be observed with an optical microscope, and the emulsion has been stabilized even after being left for a long time. I didn't see it. As described above, it is necessary to pay attention to the stability of the emulsion when handling it. The method (I), (II) of the present invention,
In (III), a dispersion medium composed of a water-immiscible liquid
For the amount of viscose liquid to be added,
Physical properties such as viscosity and the type of surfactant
Although it is affected by the temperature of
No phase transition from John region to O / W emulsion region
In other words, the addition amount may be within the W / O emulsion region.

As the pulp source of viscose used in the methods (I), (II) and (III) of the present invention, it is preferable to use cotton linter pulp, but it is also possible to use general softwood pulp or hardwood pulp. Good. The viscose liquid used in the method of the present invention is not limited to the ordinary viscose concentration for rayon (about 8%), but may be used after dilution.

In the methods (I), (II) and (III) of the present invention, the coagulation and neutralization of the viscose liquid may be carried out simultaneously or with time.

The coagulating solution of the viscose solution used in the methods (I) and (III) of the present invention includes, for example, an inorganic acid, an alkali metal salt or an alkaline earth metal salt of an inorganic acid, an organic acid, an acid gas or a mixture thereof. Are preferably used. As the inorganic acid, for example, sulfuric acid, hydrochloric acid, phosphoric acid, carbonic acid and the like can be used. Examples of the alkali metal salts of inorganic acids include Na salts such as NaCl and Na ₂ SO ₄ , and K ₂ S
K salts such as O ₄ are preferable. Examples of the alkaline earth metal salts of inorganic acids include Mg salts such as MgSO ₄ and CaCl _2.
Salts and Ca salts are preferred. The organic acid is preferably a carboxylic acid or a sulfonic acid, for example, formic acid, acetic acid,
Propionic acid, benzenesulfonic acid, maleic anhydride,
Oxalic acid or the like can be used.

The acidic gas used in the method (II) of the present invention is preferably a carbon dioxide gas, a sulfurous acid gas, a hydrogen chloride gas or the like. In addition, the coagulation reaction of viscose in the method (I) of the present invention tends to be accelerated by increasing the temperature of the reaction mixture after adding the viscose coagulation liquid emulsion to the viscose emulsion.

In the methods (I), (II) and (III) of the present invention, the acid used as a neutralizing agent for the formed cellulose fine particles includes, for example, inorganic acids such as sulfuric acid and hydrochloric acid, and organic acids such as acetic acid. Acids are preferred. In addition, since these inorganic or organic acids have a coagulating action on viscose,
By using such an inorganic acid or an organic acid,
The coagulation reaction and the neutralization reaction of viscose can be performed simultaneously.

In the methods (I), (II) and (III) of the present invention, the particle diameter of the obtained spherical cellulose fine particles is determined not only by the interfacial tension of the viscose emulsion but also by the viscose emulsion and the viscose coagulating liquid. It is influenced by the stirring conditions when the emulsion is formed, the stirring conditions when mixing and reacting the respective emulsion liquids, and the like. If the conditions other than the stirring conditions are the same, the particle size of the obtained spherical cellulose fine particles tends to be smaller under stronger stirring conditions. Further, depending on the emulsion forming conditions, cellulose fine particles having a small particle size can be obtained even with gentle stirring.

With respect to the shape of the cellulose fine particles, a true spherical shape, a spherical shape having irregularities on the surface, or an elliptical spherical shape can be produced by appropriately controlling the production conditions of the cellulose fine particles.

[0031]

The present invention will be described in detail with reference to the following examples.

Example 1 A cotton linter pulp having an absolute dry weight of 16 g and a concentration of 18%
Was added to 400 ml of an aqueous solution of sodium hydroxide, and immersed at room temperature for 2 hours. After suction-filtration of the mixture, the filtered linter pulp was pressed so that the total weight became about 68 g. Furthermore, this pressed linter pulp is
Aged at 5 ° C. for 65 hours. Next, 16 ml of carbon disulfide was added to the obtained aged alkali cellulose, and the mixture was stirred for 5 hours to obtain sulfurate to prepare xanthate. This xanthate is added to a 6% aqueous sodium hydroxide solution 21 at a temperature of 0 ° C.
The solution was dissolved in 6 ml, and further stirred for 3 hours to homogenize to prepare a viscose solution having a cellulose concentration of 7% by weight.

4 ml of the above viscose solution and 0.2 mol of surfactant (trade name: Emulgen 906, manufactured by Kao Corporation) / 1 kg of cyclohexane were added to 200 g of cyclohexane. The mixture was stirred at 8000 rpm for 60 minutes with a stirrer (trade name: TK Ajihomomixer 2M-03, manufactured by Tokushu Kika Kogyo Co., Ltd.) at a temperature of 25 ° C. for 60 minutes. A viscose emulsion was prepared. The interfacial tension between the liquid mixture of 0.2 mol of the surfactant / 1 kg of cyclohexane and cyclohexane and the viscose liquid was 1.3 dyne / cm.

Similarly, a viscose coagulating liquid of 10
% Sulfuric acid + 13% sodium sulfate solution and 0.2 mol of surfactant (trademark: Emulgen 906, manufactured by Kao Corporation) / 1 kg of cyclohexane are added to 200 g of cyclohexane in a 500 ml flask. And P
1200 rp using a stirrer having a TFE stirrer (trademark: Magnet stirrer HS-4SP, manufactured by Iuchi Seieido)
The mixture was stirred for 60 minutes to prepare a W / O viscose coagulation liquid emulsion.

The viscose emulsion was added to the viscose coagulated liquid emulsion, and 120 parts
The mixture was reacted at 0 rpm with stirring for 6 hours. When the above emulsions were mixed, cellulose fine particles were generated with the passage of time, and the mixture became cloudy. After stirring for 6 hours, the reaction solution was put into an evaporator, cyclohexane was evaporated, ethanol was further added, the remaining cyclohexane was removed again by the evaporator, and about 300 ml of ethanol was again added to dissolve and remove the surfactant from the cellulose fine particles. Thereafter, the reaction mixture was poured to a pore size of 0.1 μm.
And filtered to remove sodium sulfate in the reaction mixture.
% Cellulose, 200 ml of a 1: 1 mixture of water: ethanol and 200 ml of a 7: 3 mixture of water: ethanol were subjected to filtration and washing to separate spherical cellulose particles. Observation of the obtained spherical cellulose particles using an S-510 scanning electron microscope manufactured by Hitachi, Ltd. revealed that the average particle size was 1.7 μm,
The maximum particle size was 9 μm, and the proportion of particles having a particle size within an average particle size of ± 5 μm was 87% of the total particle weight.

Example 2 A bleached softwood kraft pulp was dried at a concentration of 1 g at an absolute dry weight of 16 g.
It was mixed with 400 ml of an 8% aqueous sodium hydroxide solution and immersed at room temperature for 2 hours. After suction-filtration of the mixture, the filtrate was squeezed so that the total weight was about 68 g. The compressed softwood bleached kraft pulp was aged at 25 ° C. for 65 hours. Next, carbon sulfide 1 was added to this aged alkaline cellulose.
6 ml was added, and the mixture was stirred for 5 hours and sulfurized to prepare xanthate. The xanthate was dissolved in 216 ml of a 6% aqueous sodium hydroxide solution at a temperature of 0 ° C., and further stirred for 3 hours to homogenize to prepare a viscose liquid having a cellulose concentration of 7% by weight.

The above viscose solution was diluted 5 times ( weight ) with a 6% aqueous sodium hydroxide solution, and 4 ml of the diluted solution was used.
And a surfactant (trademark: Emulgen 906, Kao Corporation)
0.2 mol / kg of cyclohexane was added to 200 g of cyclohexane. In addition, a temperature of 10
The mixture was stirred at 4,000 rpm for 60 minutes at ℃ with a stirrer (trademark: TK Ajihomomixer 2M-03, manufactured by Tokushu Kika Kogyo KK) to prepare a W / O viscose emulsion. The interfacial tension between the mixed solution of 0.2 mol of the surfactant / 1 kg of cyclohexane and cyclohexane and the viscose liquid diluted 5 times was 0.1 dyne / cm or less.

Similarly, a 10% viscose coagulating liquid was used.
% Sulfuric acid solution and a surfactant (trademark: Emulgen 90)
6, Kao Corporation) 0.2 mol / kg of cyclohexane was added to 200 g of cyclohexane in a 500 ml flask, and this mixture was stirred at a temperature of 10 ° C. with a stirrer having a PTFE stirrer (trademark: Magnet stirrer HS
Using -4SP (manufactured by Iuchi Seieido Co., Ltd.), the mixture was stirred at 1200 rpm for 60 minutes to prepare a W / O viscose coagulation liquid emulsion.

The viscose emulsion liquid was added to the viscose coagulation liquid emulsion, and
The mixture was stirred at 00 rpm for 10 minutes, and then left to stand to react the two solutions. When both emulsions were mixed, cellulose fine particles were precipitated over time and became cloudy.

The above emulsion reaction solution was put into an evaporator, and cyclohexane was evaporated and dispersed in ethanol. One to two drops of this dispersion was dropped on a formbar film sheet mesh for transmission electron microscopy observation, air-dried, and observed using a H-300 transmission electron microscope manufactured by Hitachi, Ltd. to find that the average particle size was The diameter was 0.2 μm, and the particle size range was 0.02 to 0.6 μm.

Example 3 A cotton linter pulp having an absolute dry weight of 16 g and a concentration of 18%
Was mixed with 400 ml of an aqueous sodium hydroxide solution, and immersed at room temperature for 2 hours. This mixture was suction-filtered and then squeezed so that the total weight was about 68 g. The compressed softwood bleached kraft pulp was aged at 25 ° C. for 65 hours. Next, 16 ml of carbon disulfide was added to the aged alkaline cellulose, and the mixture was stirred for 5 hours to sulfide to prepare xanthate.
The xanthate was dissolved in 216 ml of a 6% aqueous sodium hydroxide solution at a temperature of 0 ° C., and further stirred for 3 hours to homogenize to prepare a viscose liquid having a cellulose concentration of 7% by weight.
This viscose solution was diluted 5-fold (weight) with a 6% aqueous sodium hydroxide solution, and 20 ml of the diluted solution was mixed with 0.3 ml of a surfactant (trade name: Emulgen 705, manufactured by Kao Corporation).
1 kg of mol / n-hexane was added to 200 g of n-hexane. Further, a stirrer (trademark: TK Ajihomomixer 2M-03 type, at a temperature of 10 ° C.)
The mixture was stirred at 4,000 rpm for 60 minutes with a specialty chemical company, to produce a W / O viscose emulsion. The interfacial tension between the viscose liquid and the n-hexane mixed solution of 0.3 mol / n-hexane of 1 kg of the surfactant was 0.7 dyne / cm.

Similarly, a viscose coagulating liquid of 15
10% by weight of hydrochloric acid and a surfactant (trademark: Emulgen 7)
05, manufactured by Kao Corporation) 0.2 mol / n-hexane 1 kg
Was added to 200 g of n-hexane in a 500 ml flask, and the mixture was stirred at a temperature of 10 ° C. with a stirrer having a PTFE stirrer (trademark: Magnet Stirrer HS)
-4SP (manufactured by Iuchi Seieido Co., Ltd.) at 1200 rpm for 60 minutes to prepare a W / O viscose coagulation liquid emulsion.

The viscose emulsion was added to the viscose coagulated liquid emulsion, and 120 parts
After stirring at 0 rpm for 1 hour to allow the two to react, the temperature of the mixture was raised to 50 ° C. and the mixture was further stirred for 3 hours to form cellulose fine particles. The reaction product was put into an evaporator to evaporate n-hexane, ethanol was further added, the remaining n-hexane was removed again by the evaporator, and about 300 ml of ethanol was again added to dissolve and remove the surfactant from the cellulose fine particles. Thereafter, the mixture was filtered through a filter having a pore size of 0.1 μm, and the filtrate was washed with ethanol 1 to remove sodium sulfate.
200% liquid, 200 ml of a 1: 1 mixture of water: ethanol,
The mixture was filtered and washed with 200 ml of a 7: 3 mixture of water and ethanol to separate spherical cellulose particles.

Observation of the obtained spherical cellulose particles with an S-510 scanning electron microscope manufactured by Hitachi, Ltd. revealed that the average particle size was 0.7 μm and the maximum particle size was 4 μm.

Example 4 Condensed bleached kraft pulp was dried at a concentration of 1 g at an absolute dry weight of 16 g.
It was mixed with 400 ml of an 8% aqueous sodium hydroxide solution and immersed at room temperature for 2 hours. After suction-filtration of the mixture, the filtrate was squeezed so that the total weight was about 68 g. The compressed softwood bleached kraft pulp was aged at 25 ° C. for 65 hours. Next, this aged alkali cellulose was treated with carbon disulfide 16
ml was added and stirred for 5 hours to sulfide to prepare xanthate. The xanthate was dissolved in 216 ml of a 6% aqueous sodium hydroxide solution at a temperature of 0 ° C., and the solution was further stirred for 3 hours to homogenize to prepare a viscose liquid having a cellulose concentration of about 7% by weight.

The above viscose solution was diluted 5 times (weight) with a 6% aqueous sodium hydroxide solution, and 4 ml of the diluted solution was used.
And 0.2 mol of surfactant (trademark: Aerosol-OT, manufactured by Cyanamid) / 1 kg of cyclohexane were added to 200 g of cyclohexane. Also, add 1
At 0 ° C., a stirrer (trade name: TK Ajihomomixer 2M-03, manufactured by Tokushu Kika Kogyo Co., Ltd.) at 8000 rpm
Was stirred for 60 minutes to produce a W / O viscose emulsion. The interfacial tension between the liquid in which 0.2 mol of surfactant / 1 kg of cyclohexane was added to cyclohexane and the viscose liquid was 3.5 dyne / cm.

Similarly, a viscose coagulating liquid of 10
% Sulfuric acid solution and a surfactant (trademark: Aerosol-O)
T, manufactured by Cyanamid Co.) 0.2 mol / kg of cyclohexane was added to 200 ml of cyclohexane in a 500 ml flask.
g, and the mixture was added to PT at a temperature of 10 ° C.
120 using a stirrer having a stirrer made of FE (trademark: Magnet stirrer HS-4SP, manufactured by Iuchi Seieido).
The mixture was stirred at 0 rpm for 60 minutes to prepare a W / O viscose coagulation liquid emulsion.

The viscose emulsion was added to the viscose coagulated emulsion, and 1200 g
Both emulsions were reacted by stirring at rpm for 6 hours. The resulting reaction product solution was treated in the same manner as in Example 1, and the obtained spherical cellulose particles were observed with a S-510 scanning electron microscope manufactured by Hitachi, Ltd. to find that the average particle size was 11 μm and the maximum particle size was 11 μm. Diameter is 25 μm, average particle size ± 5
The weight ratio of particles having a particle size of μm to all particles is 7
6%.

Example 5 A cotton linter pulp having an absolute dry weight of 16 g and a concentration of 18%
Was mixed with 400 ml of an aqueous solution of sodium hydroxide, and immersed at room temperature for 2 hours. After suction-filtration of the mixture, the filtrate was squeezed so that the total weight was about 68 g. The pressed linter pulp was aged at 25 ° C. for 65 hours. Add 16 ml of carbon disulfide to this aged alkali cellulose and add 5 ml.
The mixture was sulfurized by stirring for a period of time to prepare xanthate. This xanthate is dissolved in a 6% strength aqueous sodium hydroxide solution 2 at a temperature of 0 ° C.
This was dissolved in 16 ml, and the mixture was stirred for 3 hours to homogenize to prepare a viscose liquid having a cellulose concentration of 7% by weight.

4 ml of the viscose liquid prepared above and a surfactant (trade name: Emulgen 906, manufactured by Kao Corporation) 0.2
Mol / cyclohexane 1 kg
g. Also, at a temperature of 45 ° C.,
Stirrer (trademark: TK Ajihomomixer 2M-03)
8000 rpm with a mold (manufactured by Tokushu Kika Kogyo Co., Ltd.).
This was applied for 0 minutes to produce a W / O viscose emulsion.

While stirring this viscose emulsion, sulfurous acid gas was introduced into the emulsion through a nozzle.
The mixture was blown in at a rate of 0 ml / min for 2 minutes, and further stirred for 3 hours. The obtained reaction product solution was treated in the same manner as in Example 1, and the obtained spherical cellulose particles were observed with a Hitachi S-510 scanning electron microscope. Was 6 μm.

Example 6 A cotton linter pulp having an absolute dry weight of 16 g and a concentration of 18%
Was mixed with 400 ml of an aqueous solution of sodium hydroxide, and immersed at room temperature for 2 hours. After suction-filtration of the mixture, the filtrate was squeezed so that the total weight was about 68 g. The pressed linter pulp was aged at 25 ° C. for 65 hours. To this aged alkali cellulose, 16 ml of carbon disulfide was added, and the mixture was stirred for 5 hours to sulfide to prepare xanthate. This xanthate is added to a 6% aqueous sodium hydroxide solution 2 at a temperature of 0 ° C.
The mixture was dissolved in 16 ml and further stirred for 3 hours to homogenize, thereby preparing a viscose solution having a cellulose concentration of 7% by weight.

4 ml of the above viscose solution and 0.2 mol of a surfactant (trade name: Emulgen 906, manufactured by Kao Corporation) / 1 kg of cyclohexane were added to 200 g of cyclohexane. The mixture was stirred at 8000 rpm for 60 minutes at 45 ° C. with a stirrer (trademark: TK Ajihomomixer 2M-03, manufactured by Tokushu Kika Kogyo Co., Ltd.) for 60 minutes. A viscose emulsion was prepared.

A mixture of 4 mol of 10% sulfuric acid and a cyclohexane solution containing 0.2 mol of a surfactant (trade name: Emulgen 906, manufactured by Kao Corporation) / 1 kg of cyclohexane was passed through a thin tube, and the viscose emulsion was passed through the tube. While stirring, the mixture was dropped at a flow rate of 0.5 ml / min, and the obtained mixture was further stirred for 4 hours. The resulting reaction product
The liquid was treated in the same manner as in Example 1 to obtain a spherical cell.
Loin particles were transferred to a Hitachi S-510 scanning electron microscope.
When observed using, the average particle size is 1.5 μm,
The maximum particle size was 8 μm.

Example 7 A cotton linter pulp having an absolute dry weight of 16 g was concentrated at a concentration of 18%.
% Aqueous sodium hydroxide solution at 400 ml
For 2 hours. After suction filtration of this solution, it is squeezed to
The amount was about 68 g. Furthermore, this squeezed
The cotton linter pulp was aged at 25 ° C. for 65 hours.
Next, aged alkali cellulose was added to carbon disulfide 16m.
and then sulfurated by stirring for 5 hours to prepare xanthate.
Was. This xanthate is treated with 6% sodium hydroxide at a temperature of 0 ° C.
Dissolved in 216 ml of an aqueous solution of
Prepare a viscose liquid with a cellulol concentration of 7% by weight.
Made. Dilute the viscose liquid 5 times with distilled water,
120 ml of the diluted solution and a surfactant (trade name, manufactured by Kao Corporation)
Mark: Emulgen 906) 0.2 mol / cyclohexane
1 kg was added to 200 g of cyclohexane. Also,
At a temperature of 10 ° C. K. Ajihomo mixer
8000 with 2M-03 type (trademark, manufactured by Tokushu Kika Kogyo)
The viscose W / O type emma is agitated for 60 minutes.
A fusion was prepared. Also, viscose solidification medium
15% of 15% sulfuric acid solution as Japanese liquid and Kao Corporation, KAI
Surfactant (trademark: Emulgen 906) 0.2 mol / cm
1 kg of chlorohexane is stored in a 500 ml flask.
200 g of cyclohexane
In Magnet stirrer HS-4S manufactured by Inoue Seieido
1200 rpm using Teflon stirrer
m for 60 minutes and the viscose coagulation / neutralization liquid W
A / O emulsion was prepared. This viscose coagulation liquid
Adding the viscose emulsion to the emulsion,
This was stirred at 1200 rpm for 10 minutes, and then
It was left to react. Mix both emulsions
Then, the reaction solution became cloudy with time. The above emulge
Put the reaction mixture in an evaporator and add cyclohexane.
Evaporated and dispersed in ethanol. This dispersion is
~ 2 drops, formvar membrane for transmission electron microscopy observation
Drop it on a tomesh, air-dry it, and use H
Observed using a -300 (trademark) transmission electron microscope
Roller, average particle size 0.2 μm , particle size range 0.02 to 0.7
μm.

[0056]

According to the present invention, spherical cellulose fine particles having a smaller particle size than conventionally known cellulose fine particles can be produced. The obtained cellulose fine particles can be used in a wide range of industrial fields as chromatography materials such as ion exchange and affinity, polymer carriers, cosmetic additives, food additives, lubricants and the like.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-52-129788 (JP, A) JP-A-55-47130 (JP, A) JP-A-56-74130 (JP, A) JP-A-62-129 79231 (JP, A) JP-A-2-235944 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B01J 2/06 C08B 1/00-37/18 C08J 3/12- 3/16

Claims (4)

(57) [Claims] To 1. A dispersing medium composed of water-immiscible liquid substance, viscose liquid, and the surfactant was added, to prepare a viscose emulsion of water / oil type, apart from the water immiscible liquid A viscose coagulation liquid is added to a dispersion medium comprising a water / oil type viscose coagulation liquid emulsion, and these two emulsion liquids are mixed and reacted with each other to form a spherical particle having an average particle diameter of 15 μm or less. A method for producing spherical cellulose fine particles, comprising forming cellulose fine particles. To 2. A dispersant consisting of water-immiscible liquid substance, viscose liquid, and the surfactant was added, to prepare a viscose emulsion of water / oil type, acid gases in the viscose emulsion And the viscose emulsion is allowed to react with the acid gas to obtain an average particle size of 15 μm.
A method for producing spherical cellulose fine particles, comprising forming the following spherical cellulose fine particles. 3. A viscose liquid and a surfactant are added to a dispersion medium composed of a water-immiscible liquid to prepare a water / oil type viscose emulsion, and the viscose emulsion is stirred. A method for producing spherical cellulose fine particles, wherein a viscose coagulating liquid or a mixed liquid of a viscose coagulating liquid and a surfactant is dropped thereto to form spherical cellulose fine particles having an average particle diameter of 15 μm or less. . 4. The spherical cellulose fine particles according to claim 1, wherein the interfacial tension between the mixture of the dispersant and the surfactant and the viscose liquid is 5 dyne / cm or less. Production method.