JPH05200268A - Production of spherical fine cellulose particles - Google Patents

Abstract

PURPOSE:To produce fine particles by adding a viscose solution and a surfactant to a dispersing medium composed of a water immiscible liquid to prepare a water/oil type viscose emulsion and separately adding a viscose coagulating solution to the dispersing medium to prepare a water/oil type viscose coagulating emulsion and mixing both emulsions. CONSTITUTION:A viscose solution and a surfactant are added to a dispersing medium (e.g. cyclohexane) composed of a water immiscible liquid to prepare a water/oil type viscose emulsion. Separately, a viscose coagulating solution (e.g. sulfiric acid) is added to the dispersing medium composed of a water immiscible liquid to prepare a water/oil type viscose coagulating emulsion. Both emulsions are mixed to be mutually reacted. As a result, spherical cellulose fine particles having an average particle size of 15mum or less small as compared with that of conventional ones and particle size distribution wherein the content of particles with an average particle size of + or -5mum occupies 60wt.% or more of all of particles can be produced.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION 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 composed of regenerated cellulose and having a finer particle diameter than conventional ones.

[0002]

BACKGROUND 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.

[0003] Conventionally, as a method for producing cellulose particles, Japanese Patent Publication No. 52-11237 discloses that an aqueous solution of copper copper is added dropwise to a benzene solution in which an emulsifier is dissolved, and this emulsion is dissolved in benzene to dissolve benzoic acid or acetic acid. The method of feeding into the regenerating bath is disclosed. However, in this method, since the diameter of the small droplets of the cellulose copper ammonium solution is large, the particle size of the cellulose fine spheres is only 30 to 315 μm, and only a large particle size can be obtained. ..

Further, in JP-A-61-241337, a viscose solution and a water-soluble anionic polymer compound are mixed and stirred, and viscose is solidified into fine particles at a temperature of 70 ° C. 20μ after neutralization with acid and regeneration
A method for producing spherical or oblong fine cellulose particles having an average particle diameter of m or less is disclosed.

Further, in JP-A-48-21738, viscose having an average degree of polymerization of 400 or more is dropped into a coagulation regenerating bath having a low acid concentration and a low Glauber's salt concentration to coagulate. A method for producing regenerated cellulose granules having a size of 30 to 46 mesh (300 to 590 μm) by gradually performing regeneration is disclosed.

Further, in Japanese Patent Publication No. 56-21761, viscose is extruded from a discharge port, and the extruded liquid flow is changed into a liquid droplet flow, which is dripped into a coagulation / regeneration bath as almost spherical liquid droplets. 16-170 mesh (88-
A method for producing cellulosic granules having a size of 1168 μm) is described.

Further, in Japanese Patent Publication No. 49-89748 and Japanese Patent Laid-Open No. 57-212231, the fibrous material of regenerated cellulose or the fibrous material of natural cellulose is hydrolyzed, dried and pulverized, 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, in JP-B-57-45254, a viscose suspension is added to a water-insoluble liquid (for example, chlorobenzene), and the mixture is continuously stirred at a temperature of 30 to 100 ° C. Disclosed is a method for producing cellulose fine particles in which the content of particles having a particle diameter of 150 to 350 μm is 85% by volume or more by heating to solidify viscose and then dispersing the produced particles in a water-soluble acid solution. Has been done.

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

Furthermore, Japanese Patent Publication No. 55-40618 discloses that from cellulose esters other than cellulose triacetate,
A method for producing cellulose particles having a particle diameter of 50 to 500 μm is disclosed by the same method as above.

Further, in JP-A-55-28763, a cellulose fatty acid ester is dissolved in a mixed solvent of three or more kinds of solvents having a boiling point difference of 30 ° C. or more, and the solution is spray-dried. A method for producing fine spherical particles having an average particle size of 30 μm is disclosed.

Further, JP-A-57-159801 discloses that paraformaldehyde and dimethyl sulfoxide (D
Cellulose is dissolved in a mixed solution with MSO), the resulting solution is dispersed in a liquid in which DMSO is not dissolved, for example, liquid paraffin, and the dispersion is mixed with a coagulant for cellulose. , A method of producing spherical cellulose gel having a particle size of 50 to 500 μm by gelling and aggregating dispersed droplets of cellulose and regenerating with warm water as necessary.

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

[0014]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
Particles having an average particle size smaller than that of the conventional ones below, and preferably having a particle size variation of ± 5 μm from the average particle size account for 60% (weight) or more of all particles. An object of the present invention is to provide a method for producing spherical cellulose particles having a distribution.

[0015]

In the conventional method for granulating cellulose, the average particle size of the obtained cellulose particles is large,
Further, although there is a problem that the range of variation in particle size is wide, the present inventors have focused on the emulsification of cellulose, particularly the effect of micronizing cellulose by using a water / oil type (W / O type) cellulose emulsion. However, the present invention has been completed by succeeding in producing fine spherical cellulose particles to a degree that could not be achieved by the conventional method.

In the method (I) for producing spherical cellulose fine particles of the present invention, a viscose solution and a surfactant are added to a dispersion medium composed of a water-immiscible liquid to prepare a water / oil type viscose emulsion solution. And a viscose coagulation liquid was added to a dispersion medium composed of a water-immiscible liquid to prepare water /
An oil-type viscose coagulation liquid emulsion was prepared, and both emulsions were mixed and reacted with each other to give an average particle size of 15 μm.
It is characterized in that spherical cellulose fine particles of m or less are formed.

In another method (II) for producing spherical cellulose fine particles of the present invention, 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. An emulsion is prepared, and acidic gas is blown into the viscose emulsion, and the viscose emulsion and the acidic gas are reacted with each other to form spherical cellulose fine particles having an average particle diameter of 15 μm or less.

Still another method for producing spherical cellulose fine particles (III) of the present invention is to use a dispersion medium composed of a water-immiscible liquid,
A viscose emulsion of water / oil type is prepared by adding a viscose liquid and a surfactant, and the viscose emulsion is agitated while being mixed with a viscose coagulating liquid or a viscose coagulating liquid and a surfactant. The spherical cellulose fine particles having an average particle diameter of 15 μm or less are formed by dropping the mixture into the mixed liquid.

[0019]

In the methods (I), (II) and (III) of the present invention,
As the dispersion medium used, an organic solvent immiscible with water is used. Examples of dispersion media that are 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, but organic solvents usable in the present invention. Is not limited to the above, and any solvent that does not react with the viscose liquid or the viscose coagulating liquid can be used. These organic solvents may be used alone or in a mixture.

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

The present inventors have investigated the compatibility of the combination of the dispersion medium, the viscose liquid, and the viscose coagulating liquid used with the surfactant with the surface tensiometer (trademark: FACE).
CBVP-A3 type surface tensiometer, Kyowa Interface Science Co., Ltd.
As a result of various investigations using the same), it was found that it is preferable to select the surfactant so that the interfacial tension of the W / O type viscose emulsion is 5 dyne / cm or less. The surfactant may consist of a single component,
It may be a mixture of two or more components. In addition, as a surfactant, a surface-active auxiliary agent (co-sur
You may add what becomes a factor).

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

Further, a W / O type viscose emulsion,
When the interfacial tension of the W / O type viscose coagulating liquid emulsion is high, the stability of the fine liquid particles in the emulsion decreases, and the fine liquid particles in the emulsion coalesce within a short time depending on the conditions. Sometimes. For this reason, it is preferable to sufficiently stir each emulsion and to react them immediately after their formation. On the other hand, 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 / cyclohexane 1 kg
The measured interfacial tension of the emulsion liquid obtained by adding the
Since it is ne / cm or less, the emulsion particles cannot be observed with an optical microscope in this state, and the emulsion is stable even after being left for a long time. I couldn't see it. As described above, it is necessary to pay attention to the stability when handling the emulsion.

As the pulp source of viscose used in the methods (I), (II) and (III) of the present invention, cotton linter pulp is preferably used, but general softwood pulp or hardwood pulp is also used. Good. Further, the viscose solution used in the method of the present invention is not limited to the usual viscose solution for rayon (about 8%), and it may be diluted before use.

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

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

As the acidic gas used in the method (II) of the present invention, carbon dioxide gas, sulfurous acid gas, hydrogen chloride gas and the like are preferable. Further, the viscose coagulation reaction 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 is, for example, an inorganic acid such as sulfuric acid or hydrochloric acid, or an organic acid such as acetic acid. Acids are preferred. In addition, since these inorganic acids or organic acids have a coagulating action on viscose,
By using such an inorganic acid or an organic acid,
The viscose coagulation reaction and neutralization reaction can be carried out simultaneously.

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

Regarding the shape of the cellulose fine particles, by controlling the production conditions of the cellulose fine particles appropriately, it is possible to produce a true spherical shape, a spherical shape having irregularities on the surface, or an elliptic spherical shape.

[0031]

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

Example 1 An absolute dry weight of 16 g of cotton linter pulp was added to a concentration of 18%.
Was added to 400 ml of an aqueous solution of sodium hydroxide, and the mixture was immersed at room temperature for 2 hours. After suction-filtering this mixed solution, the filtered linter pulp was squeezed to a total weight of about 68 g. 2 more of this pressed linter pulp
Aged at 5 ° C. for 65 hours. Next, 16 ml of carbon disulfide was added to the obtained aged alkali cellulose, and this mixture was stirred for 5 hours to be sulfurized to prepare xanthate. This xanthate is mixed with a 6% aqueous sodium hydroxide solution 21 at a temperature of 0 ° C.
It was dissolved in 6 ml and further stirred for 3 hours for homogenization 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 a surfactant (trademark: Emulgen 906, manufactured by Kao Corporation) / 1 kg of cyclohexane were added to 200 g of cyclohexane. Further, this mixture was stirred at a temperature of 25 ° C. with a stirrer (trademark: TK Ajihomomixer 2M-03 type, manufactured by Tokushu Kika Kogyo Co., Ltd.) for 60 minutes at 8000 rpm to obtain a W / O type. A viscose emulsion was prepared. The interfacial tension between the viscose solution and a mixed solution of 0.2 mol of the surfactant / 1 kg of cyclohexane and cyclohexane was 1.3 dyne / cm.

Similarly, as the viscose coagulating liquid, 10
% Sulfuric acid + 13% sodium sulfate solution 4 ml and a surfactant (trademark: Emulgen 906, manufactured by Kao Co., Ltd.) 0.2 mol / cyclohexane 1 kg are added to cyclohexane 200 g in a 500 ml flask and the temperature is 25 ° C. And then P
1200 rp using a stirrer having a TFE stirrer (trademark: Magnet Stirrer HS-4SP, manufactured by Inei Seieidou)
The mixture was stirred for 60 minutes to prepare a W / O type viscose coagulation liquid emulsion.

The above viscose emulsion was added to this viscose coagulation liquid emulsion, and 120
Both were reacted by stirring at 0 rpm for 6 hours. When the above two emulsions were mixed, cellulose fine particles were produced over time, and the mixed solution became cloudy. After stirring for 6 hours, the reaction solution was placed in an evaporator, cyclohexane was evaporated, ethanol was further added, the remaining cyclohexane was removed by the evaporator again, and about 300 ml of ethanol was added again to dissolve and remove the surfactant from the cellulose fine particles. After that, the reaction mixture is added with a pore size of 0.1 μm.
The mixture was filtered with a filter of 100 to remove sodium sulfate in the reaction mixture.
% Liquid, 200 ml of a 1: 1 mixture of water: ethanol and 200 ml of a 7: 3 mixture of water: ethanol were used for filtration and washing to separate spherical cellulose particles. When the obtained spherical cellulose particles were observed using a S-510 scanning electron microscope manufactured by Hitachi Ltd., the average particle size was 1.7 μm,
The maximum particle size was 9 μm, and the ratio of particles having an average particle size of ± 5 μm was 87% of the total particle weight.

Example 2 Coniferous bleached kraft pulp 16 g of absolute dry weight was added at a concentration of 1
The mixture was mixed with 400 ml of an 8% aqueous sodium hydroxide solution and immersed at room temperature for 2 hours. After suction filtration of this mixed solution, the filtered product was squeezed to a total weight of about 68 g. The pressed softwood bleached kraft pulp was aged at 25 ° C. for 65 hours. Next, 1 carbon disulfide was added to this aged alkaline cellulose.
Xanthate was prepared by adding 6 ml and stirring for 5 hours for sulfurization. This xanthate was dissolved in 216 ml of a 6% sodium hydroxide aqueous solution at a temperature of 0 ° C. and further stirred for 3 hours to homogenize it, thereby preparing a viscose liquid having a cellulose concentration of 7% by weight.

The above viscose solution was diluted 5 times (volume) with a 6% aqueous sodium hydroxide solution, and 4 ml of this diluted solution was added.
And a surfactant (trademark: Emulgen 906, Kao Corporation)
0.2 mol / 1 kg of cyclohexane) was added to 200 g of cyclohexane. In addition, a temperature of 10
The mixture was stirred at 4000 ° C. for 60 minutes with a stirrer (trademark: TK Ajihomomixer 2M-03, manufactured by Tokushu Kika Kogyo Co., Ltd.) to prepare a W / O type 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 solution diluted 5 times was 0.1 dyne / cm or less.

Similarly, as the viscose coagulating liquid, 10
% Sulfuric acid solution 4 ml and surfactant (Trademark: Emulgen 90
6, Kao Corporation 0.2 mol / cyclohexane 1 kg was added to cyclohexane 200 g in a 500 ml flask, and the mixture was stirred at a temperature of 10 ° C. with a stirrer made of PTFE (trademark: Magnet stirrer HS
-4SP, manufactured by Iuchi Seieidou Co., Ltd., and stirred at 1200 rpm for 60 minutes to prepare a W / O type viscose coagulation liquid emulsion.

The above viscose emulsion liquid was added to this viscose coagulation liquid emulsion, and 12
Stirring was performed at 00 rpm for 10 minutes, and then the mixture was left to stand to react both solutions. When both emulsions were mixed, cellulose fine particles were deposited over time and turned into a cloudy state.

The above emulsion reaction solution was placed in an evaporator, cyclohexane was evaporated, and dispersed in ethanol. One to two drops of this dispersion were dropped onto a form-bar membrane sheet mesh for transmission electron microscope observation, air-dried, and observed using a H-300 transmission electron microscope manufactured by Hitachi Ltd. The diameter was 0.2 μm and the particle size range was 0.02 to 0.6 μm.

Example 3 An absolutely dry weight of 16 g of cotton linter pulp was added to a concentration of 18%.
Was mixed with 400 ml of an aqueous solution of sodium hydroxide of, and immersed at room temperature for 2 hours. This mixed solution was suction filtered and then pressed so that the total weight became about 68 g. Further, this pressed softwood bleached kraft pulp was aged at 25 ° C. for 65 hours. Next, 16 ml of carbon disulfide was added to this aged alkaline cellulose, and the mixture was stirred for 5 hours to be sulfurized to prepare xanthate.
This 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 it to prepare a viscose solution having a cellulose concentration of 7% by weight.
This viscose solution was diluted 5 times (weight) with a 6% aqueous sodium hydroxide solution, and 20 ml of the diluted solution and a surfactant (trademark: Emulgen 705, manufactured by Kao Corporation) 0.3
Mol / n-hexane 1 kg was added to n-hexane 200 g. In addition, a stirrer (trademark: TK Ajihomomixer 2M-03 type, at a temperature of 10 ° C., was added to the mixed solution.
Stirring was performed at 4000 rpm for 60 minutes with Tokushu Kika Kogyo Co., Ltd. to prepare a W / O type viscose emulsion. The interfacial tension between the n-hexane mixed solution of 0.3 mol of this surfactant / 1 kg of n-hexane and the viscose solution was 0.7 dyne / cm.

Similarly, as the viscose coagulating liquid, 15
10% by weight 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 Inei Seieido Co., Ltd., was stirred at 1200 rpm for 60 minutes to prepare a W / O type viscose coagulation liquid emulsion.

The above viscose emulsion was added to this viscose coagulation liquid emulsion, and 120
After stirring at 0 rpm for 1 hour to react them with each other, the temperature of the mixed solution was raised to 50 ° C. and further stirred for 3 hours to form cellulose fine particles. The reaction product solution was placed in an evaporator to evaporate n-hexane, ethanol was further added to remove residual n-hexane by the evaporator again, and about 300 ml of ethanol was added again to dissolve and remove the surfactant from the cellulose fine particles. After that, the product is filtered with a filter having a pore size of 0.1 μm, and the filtered product is treated with ethanol 1 to remove sodium sulfate from the filtered product.
00% liquid, 200 ml of 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.

When the obtained spherical cellulose particles were observed with a S-510 scanning electron microscope manufactured by Hitachi, Ltd., the average particle size was 0.7 μm and the maximum particle size was 4 μm.

Example 4 Bleached kraft pulp of coniferous tree An absolute dry weight of 16 g was added to a concentration of 1
The mixture was mixed with 400 ml of an 8% aqueous sodium hydroxide solution and immersed at room temperature for 2 hours. After suction filtration of this mixed solution, the filtered product was squeezed to a total weight of about 68 g. The pressed softwood bleached kraft pulp was aged at 25 ° C. for 65 hours. Next, add 16 carbon disulfide to this aged alkaline cellulose.
ml was added, and the mixture was stirred for 5 hours for sulfurization to prepare xanthate. This xanthate was dissolved in 216 ml of a 6% sodium hydroxide aqueous solution at a temperature of 0 ° C., and the solution was further stirred for 3 hours to be homogenized 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 added.
And a surfactant (trademark: Aerosol-OT, manufactured by Cyanamid Co., Ltd.) 0.2 mol / cyclohexane 1 kg were added to cyclohexane 200 g. In addition, the temperature 1
8000 rpm with a stirrer (trademark: TK Ajihomomixer 2M-03, manufactured by Tokushu Kika Kogyo Co., Ltd.) at 0 ° C.
Was stirred for 60 minutes to prepare a W / O type viscose emulsion. The interfacial tension between the liquid in which 0.2 mol of the surfactant / 1 kg of cyclohexane was added to cyclohexane and the viscose liquid was 3.5 dyne / cm.

Similarly, as a viscose coagulating liquid, 10
% Sulfuric acid solution 4 ml and a surfactant (trademark: Aerosol-O
T, manufactured by Cyanamid) 0.2 mol / 1 kg of cyclohexane, and cyclohexane 200 in a 500 ml flask.
g and added to this mixed solution at a temperature of 10 ° C.
Using a stirrer (trademark: Magnet Stirrer HS-4SP, manufactured by Inei Seieido Co., Ltd.) having a stirrer made by FE, 120
The mixture was stirred at 0 rpm for 60 minutes to prepare a W / O type viscose coagulation liquid emulsion.

The viscose emulsion was added to the viscose-solidified emulsion, and 1200 was added to the mixed solution.
Both emulsions were reacted by stirring at rpm for 6 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 to find that the average particle diameter was 11 μm and the maximum particle diameter 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
It was 6%.

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

4 ml of the viscose solution prepared above and 0.2% of a surfactant (trademark: Emulgen 906, manufactured by Kao Corporation)
Mol / cyclohexane 1 kg, cyclohexane 200
g. Also, in this mixed solution at a temperature of 45 ° C,
Stirrer (Trademark: TK Ajihomomixer 2M-03
Type, manufactured by Tokushu Kika Kogyo Co., Ltd.) and stirred at 8000 rpm for 6
It was applied for 0 minutes to prepare a W / O type viscose emulsion.

While stirring the viscose emulsion, sulfurous acid gas was introduced into the emulsion from the nozzle 4
It was blown in for 90 minutes at a rate of 0 ml / min and stirred for a further 3 hours. The obtained reaction product solution was treated by the same method as in Example 1, and the obtained spherical cellulose particles were observed with a S-510 scanning electron microscope manufactured by Hitachi, Ltd., and the average particle size was 1.1 μm and the maximum particle size. Was 6 μm.

Example 6 Cotton linter pulp absolute dry weight 16 g, concentration 18%
Was mixed with 400 ml of an aqueous solution of sodium hydroxide of, and immersed at room temperature for 2 hours. After suction filtration of this mixed solution, the filtered product was squeezed to a total weight of about 68 g. The pressed linter pulp was aged at 25 ° C. for 65 hours. 16 ml of carbon disulfide was added to this aged alkaline cellulose, and the mixture was stirred for 5 hours to be sulfided to prepare xanthate. This xanthate is mixed with a 6% sodium hydroxide aqueous solution at a temperature of 0 ° C. 2
It was dissolved in 16 ml and further stirred for 3 hours for homogenization 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 a surfactant (trademark: Emulgen 906, manufactured by Kao Corporation) / 1 kg of cyclohexane were added to 200 g of cyclohexane. Further, this mixture was stirred at a temperature of 45 ° C. with a stirrer (trademark: TK Ajihomomixer 2M-03 type, manufactured by Tokushu Kika Kogyo Co., Ltd.) at 8000 rpm for 60 minutes to obtain W / O. A type viscose emulsion was prepared.

A viscose emulsion was prepared by mixing 4 ml of 10% sulfuric acid with a cyclohexane solution containing 0.2 mol of a surfactant (trademark: Emulgen 906, manufactured by Kao Corporation) / 1 kg of cyclohexane through a thin tube. While stirring, the mixture was added dropwise thereto at a flow rate of 0.5 ml / min, and the obtained mixed liquid was further stirred for 4 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.
The average particle size was 1.5 μm and the maximum particle size was 8 μm.

[0056]

EFFECTS OF THE INVENTION According to the present invention, spherical cellulose fine particles having a smaller particle size than the conventionally known cellulose fine particles can be produced. Further, the obtained cellulose fine particles can be used in a wide range of industrial fields as a chromatographic material such as ion exchange and affinity, a polymer carrier, a cosmetic additive, a food additive, a lubricant and the like.

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[Procedure amendment]

[Submission date] March 9, 1992

[Procedure Amendment 1]

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Further, a W / O type viscose emulsion,
When the interfacial tension of the W / O type viscose coagulating liquid emulsion is high, the stability of the fine liquid particles in the emulsion decreases, and the fine liquid particles in the emulsion coalesce within a short time depending on the conditions. Sometimes. For this reason, it is preferable to sufficiently stir each emulsion and to react them immediately after their formation. On the other hand, 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 / cyclohexane 1 kg
The measured interfacial tension of the emulsion liquid obtained by adding the
Since it is ne / cm or less, the emulsion particles cannot be observed with an optical microscope in this state, and the emulsion is stable even after being left for a long time. I couldn't see it. As described above, it is necessary to pay attention to the stability when handling the emulsion. Inventive methods (I), (II),
In (III), the dispersion medium consisting of water-immiscible liquid
For the amount of added viscose liquid, see
Physical properties such as viscosity, type of surfactant, and emulsion
It is affected by temperature, but basically it is W / O
No phase transition from John region to O / W emulsion region
The amount added may be within the W / O emulsion region.

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The above viscose solution was diluted 5 times ( weight ) with a 6% aqueous sodium hydroxide solution, and 4 ml of this diluted solution was added.
And a surfactant (trademark: Emulgen 906, Kao Corporation)
0.2 mol / 1 kg of cyclohexane) was added to 200 g of cyclohexane. In addition, a temperature of 10
The mixture was stirred at 4000 ° C. for 60 minutes with a stirrer (trademark: TK Ajihomomixer 2M-03, manufactured by Tokushu Kika Kogyo Co., Ltd.) to prepare a W / O type 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 solution diluted 5 times was 0.1 dyne / cm or less.

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While stirring the viscose emulsion, sulfurous acid gas was introduced into the emulsion from the nozzle 4
It was bubbled for 2 minutes at a rate of 0 ml / min and stirred for a further 3 hours. The obtained reaction product solution was treated by the same method as in Example 1, and the obtained spherical cellulose particles were observed with a S-510 scanning electron microscope manufactured by Hitachi, Ltd., and the average particle size was 1.1 μm and the maximum particle size. Was 6 μm.

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A viscose emulsion was prepared by mixing 4 ml of 10% sulfuric acid with a cyclohexane solution containing 0.2 mol of a surfactant (trademark: Emulgen 906, manufactured by Kao Corporation) / 1 kg of cyclohexane through a thin tube. While stirring, the mixture was added dropwise thereto at a flow rate of 0.5 ml / min, and the obtained mixed liquid 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 with S-510 scanning electron microscope manufactured by Hitachi Ltd.
When observed using, the average particle size is 1.5 μm,
The maximum particle size was 8 μm.

[Procedure correction 6]

[Document name to be amended] Statement

[Correction target item name] 0055

[Correction method] Change

[Correction content]

Example 7 A cotton linter pulp having an absolute dry weight of 16 g was prepared at a concentration of 18
% 400% sodium hydroxide aqueous solution and bring to room temperature
And soaked for 2 hours. After suction filtration of this liquid, squeeze it
The amount was adjusted to about 68 g. Furthermore, this squeezed
The cotton linter pulp was aged at 25 ° C for 65 hours.
Then, with aged alkali cellulose, carbon disulfide 16m
1 was added, and the mixture was stirred for 5 hours for sulfidation to prepare xanthate.
It was This xanthate is mixed with 6% concentration of sodium hydroxide at a temperature of 0 ° C.
Dissolve in 216 ml of aqueous solution of water and stir for another 3 hours
Uniformize and prepare a viscose solution with a cellulose concentration of 7% by weight.
Made Dilute the viscose liquid 5 times with distilled water,
120 ml of the diluted solution and a surfactant (commercially available from Kao Corporation)
Mark: Emulgen 906) 0.2 mol / cyclohexane
1 kg was added to 200 g of cyclohexane. Also, this
Liquid at a temperature of 10.degree. K. Aji Homo Mixer
8000 with 2M-03 type (trademark, manufactured by Tokushu Kika Kogyo Co., Ltd.)
After stirring for 60 minutes at rpm, viscose W / O type emma
Rouge was made. Similarly, viscose coagulation / medium
15 ml of 15% sulfuric acid solution as a Japanese solution, Kao Co., Ltd.
Surface active agent (trademark: Emulgen 906) 0.2 mol / shi
1 kg of hexane is stored in a 500 ml flask.
Was added to 200 g of cyclohexane and the temperature was 20 ° C.
And Magnet Stirrer HS-4S made by Inei Seieidou Co., Ltd.
P (trademark), 1200 rp with Teflon stirrer
The viscose coagulation / neutralizing solution W is stirred for 60 minutes
A / O type emulsion was prepared. This viscose coagulation liquid
Add the viscose emulsion liquid to the emulsion,
This is agitated at 1200 rpm for 10 minutes and then
I left it to react and let it react. Mix both emulsions above
Then, the reaction solution became cloudy over time. Above
Pour the reaction solution into the evaporator and add cyclohexane.
Evaporated and dispersed in ethanol. 1 of this dispersion
~ 2 drops, Formvar membrane sheet for transmission electron microscopy
Drop it on the tomesh, air-dry it, and use Hitachi H
When observed with a -300 (trademark) transmission electron microscope
Roller, average particle size 0.2 μm, particle size range 0.02-0.7
was μm.

Claims (5)

[Claims] 1. 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, which is separately prepared from the water-immiscible liquid. Viscose coagulation liquid is added to the dispersion medium to prepare a water / oil type viscose coagulation liquid emulsion, and both emulsion liquids are mixed and reacted with each other to give spherical cellulose having an average particle diameter of 15 μm or less. A method for producing spherical cellulose fine particles, which comprises forming fine particles. 2. A water / oil type viscose emulsion is prepared by adding a viscose liquid and a surfactant to a dispersant comprising a water immiscible liquid, and an acidic gas is added to the viscose emulsion. A method for producing spherical cellulose fine particles, which comprises blowing and reacting the viscose emulsion with the acidic gas to form spherical cellulose fine particles having an average particle diameter of 15 μm or less. 3. A water / oil type viscose emulsion is prepared by adding a viscose liquid and a surfactant to a dispersion medium composed of a water immiscible liquid, and stirring this viscose emulsion. A method for producing spherical cellulose fine particles, characterized in that a viscose coagulating liquid or a mixed liquid of a viscose coagulating liquid and a surfactant is added dropwise 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 mixed liquid of the dispersant and the surfactant and the viscose liquid is 5 dyne / cm or less. Production method. 5. The method for producing spherical cellulose fine particles according to claim 1, wherein in the first viscose emulsion, the amount of the added liquid of the viscose liquid with respect to the weight of the dispersion medium is 20% or less. ..