WO2024057830A1 - Method for grinding cellulose polymer - Google Patents

Method for grinding cellulose polymer Download PDF

Info

Publication number
WO2024057830A1
WO2024057830A1 PCT/JP2023/029955 JP2023029955W WO2024057830A1 WO 2024057830 A1 WO2024057830 A1 WO 2024057830A1 JP 2023029955 W JP2023029955 W JP 2023029955W WO 2024057830 A1 WO2024057830 A1 WO 2024057830A1
Authority
WO
WIPO (PCT)
Prior art keywords
cellulose
bead mill
pulp
beads
treatment
Prior art date
Application number
PCT/JP2023/029955
Other languages
French (fr)
Japanese (ja)
Inventor
一彦 井上
貴之 阪後
昂輝 柴田
佑馬 金子
Original Assignee
日本製紙株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 日本製紙株式会社 filed Critical 日本製紙株式会社
Publication of WO2024057830A1 publication Critical patent/WO2024057830A1/en

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
    • B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
    • B02C17/00—Disintegrating by tumbling mills, i.e. mills having a container charged with the material to be disintegrated with or without special disintegrating members such as pebbles or balls
    • B02C17/16—Mills in which a fixed container houses stirring means tumbling the charge
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
    • B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
    • B02C17/00—Disintegrating by tumbling mills, i.e. mills having a container charged with the material to be disintegrated with or without special disintegrating members such as pebbles or balls
    • B02C17/18—Details
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
    • B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
    • B02C17/00—Disintegrating by tumbling mills, i.e. mills having a container charged with the material to be disintegrated with or without special disintegrating members such as pebbles or balls
    • B02C17/18—Details
    • B02C17/20—Disintegrating members
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J3/00—Processes of treating or compounding macromolecular substances
    • C08J3/12—Powdering or granulating

Definitions

  • the present invention relates to a method for pulverizing cellulose polymers.
  • cellulose-based polymers such as carboxymethylcellulose are used in various fields for reasons such as high safety, and their use is being considered.
  • carboxymethylcellulose or a salt thereof is a product in which a carboxymethyl group is bonded to a part of the hydroxyl group of a glucopyranose monomer that constitutes the cellulose skeleton, or a carboxymethyl group is salt.
  • the quality of CMC can be adjusted by adjusting the degree of substitution of carboxymethyl groups, the length of the cellulose skeleton, etc. It is used as a binding agent, binder, water absorbing material, water retaining agent, emulsion stabilizer, etc.
  • it since it is derived from natural cellulose, it is an extremely environmentally friendly material that has gradual biodegradability and can be disposed of by incineration, and it is predicted that the applications of CMC will expand in the future.
  • Patent Document 1 describes that cellulose fiber is better than carboxymethyl cellulose when used as a binder for adhering the electrode active material of a non-aqueous secondary battery to a current collector, for example.
  • the applications of cellulose-based polymers have been limited due to
  • An object of the present invention is to provide a method for pulverizing cellulose polymers that can stably produce cellulose polymers having a particle size of less than 50 ⁇ m.
  • a method of pulverizing a cellulose polymer using a bead mill wherein the average diameter of the beads used in the bead mill is 0.1 to 10 mm, the peripheral speed of the agitator of the bead mill is 2 to 15 m/sec, and the bead filling rate of the bead mill is A method for pulverizing a cellulose-based polymer in which the amount is 50 to 90 vol%, (2) The method for pulverizing a cellulose polymer according to (1), wherein the beads have an average diameter of 3 to 8 mm; (3) The method for producing a cellulose polymer according to (1) or (2), wherein the bead mill is a dry bead mill; (4) The material of the agitator and/or vessel of the bead mill is at least one selected from zirconia, zircon, stabilized zirconia, partially stabilized zirconia, alumina, or silicon nitride (1) or (2) The method for pulverizing
  • the present invention it is possible to provide a method for pulverizing a cellulose-based polymer that can stably produce a cellulose-based polymer having a particle size of less than 50 ⁇ m.
  • FIG. 1 is a schematic diagram showing an example of a crushing device including a bead mill used in the present invention.
  • the method for pulverizing cellulose polymers of the present invention is a method for pulverizing cellulose polymers using a bead mill, wherein the beads used in the bead mill have an average diameter of 0.1 to 10 mm, and the peripheral speed of the agitator of the bead mill is 2 to 15 m/min. sec, the bead filling rate of the bead mill is 50 to 90 vol%.
  • cellulose polymer In the present invention, as the cellulose-based polymer to be pulverized, any compound derived from cellulose can be used without particular limitation, but it is preferable to use a chemically modified cellulose-based polymer or unmodified pulp.
  • Cellulose-based polymers can be obtained using cellulose as a raw material. That is, cellulose that can be used as a cellulose raw material in the present invention is a polysaccharide with a structure in which D-glucopyranose (simply referred to as "glucose residue” or “anhydroglucose”) is linked by ⁇ , 1-4 bonds. means. Cellulose is generally classified into natural cellulose, regenerated cellulose, fine cellulose, microcrystalline cellulose excluding non-crystalline regions, etc. based on its origin, manufacturing method, etc.
  • Examples of natural cellulose include bleached pulp or unbleached pulp (bleached wood pulp or unbleached wood pulp); linters, purified linters; cellulose produced by microorganisms such as acetic acid bacteria, and the like.
  • the raw material for bleached pulp or unbleached pulp is not particularly limited, and examples thereof include wood, cotton, straw, bamboo, and the like.
  • the method for producing bleached pulp or unbleached pulp is not particularly limited, and may be a mechanical method, a chemical method, or a combination of the two in between.
  • Examples of bleached pulp or unbleached pulp classified by manufacturing method include mechanical pulp, chemical pulp, groundwood pulp, sulfite pulp, and kraft pulp.
  • dissolving pulp may be used in addition to papermaking pulp. Dissolving pulp is a chemically refined pulp that is mainly used after being dissolved in chemicals, and is the main raw material for artificial fibers, cellophane, etc.
  • regenerated cellulose examples include those obtained by dissolving cellulose in some kind of solvent such as a cupric ammonia solution, a cellulose xanthate solution, or a morpholine derivative, and respinning the resulting cellulose.
  • solvent such as a cupric ammonia solution, a cellulose xanthate solution, or a morpholine derivative
  • Fine cellulose is obtained by depolymerizing cellulose materials such as the above-mentioned natural cellulose and regenerated cellulose (for example, acid hydrolysis, alkaline hydrolysis, enzymatic decomposition, blasting treatment, vibrating ball mill treatment, etc.) Examples include those obtained by mechanically processing the above-mentioned cellulose-based materials.
  • ⁇ Chemically modified cellulose polymer for example, a cellulose polymer obtained by anion modification or a cellulose polymer obtained by cation modification may be used.
  • cellulose-based polymers obtained by anionic modification include carboxylated cellulose (also called oxidized cellulose), carboxymethyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, and phosphate-esterified cellulose. may be in the form of a salt. Although the type of salt does not matter, it is preferable to select a suitable salt, such as a metal salt such as a sodium salt or an ammonium salt, depending on the use and purpose. Although there are no particular limitations on the cellulose-based polymer used in the present invention, it is preferable to use carboxymethylcellulose and/or a salt thereof.
  • carboxylated cellulose (oxidized cellulose)
  • carboxylated cellulose (oxidized cellulose)
  • carboxylated cellulose oxidized cellulose
  • it can be obtained by carboxylating (oxidizing) a cellulose raw material by a known method.
  • the amount of carboxyl groups is 2.4 to 9.3 mmol/g, preferably 3.1 to 8.0 mmol/g, more preferably 3. It is preferable to adjust it to 7 to 6.8 mmol/g.
  • a cellulosic raw material is oxidized in water with an oxidizing agent in the presence of an N-oxyl compound and a compound selected from the group consisting of bromides, iodides or mixtures thereof.
  • an oxidizing agent in the presence of an N-oxyl compound and a compound selected from the group consisting of bromides, iodides or mixtures thereof.
  • the primary hydroxyl group at the C6 position of the glucopyranose ring on the cellulose surface is selectively oxidized, resulting in cellulose fibers having an aldehyde group and a carboxy group (-COOH) or carboxylate group (-COO-) on the surface.
  • the concentration of cellulose during the reaction is not particularly limited, but is preferably 5% by mass or less.
  • the N-oxyl compound refers to a compound that can generate nitroxy radicals.
  • any compound can be used as long as it promotes the desired oxidation reaction. Examples include 2,2,6,6-tetramethylpiperidine-1-oxyradical (TEMPO) and its derivatives (eg, 4-hydroxyTEMPO).
  • TEMPO 2,2,6,6-tetramethylpiperidine-1-oxyradical
  • 4-hydroxyTEMPO 4-hydroxyTEMPO
  • the amount of the N-oxyl compound used is not particularly limited as long as it is a catalytic amount that can oxidize cellulose as a raw material.
  • it is preferably 0.01 to 10 mmol, more preferably 0.01 to 1 mmol, and even more preferably 0.05 to 0.5 mmol, per 1 g of bone dry cellulose. Further, it is preferably about 0.1 to 4 mmol/L to the reaction system.
  • a bromide is a compound containing bromine, and examples thereof include alkali metal bromides that can be dissociated and ionized in water.
  • iodide is a compound containing iodine, and examples thereof include alkali metal iodide.
  • the amount of bromide or iodide to be used can be selected within a range that can promote the oxidation reaction.
  • the total amount of bromide and iodide is, for example, preferably 0.1 to 100 mmol, more preferably 0.1 to 10 mmol, and even more preferably 0.5 to 5 mmol, per 1 g of bone dry cellulose.
  • the oxidizing agent known ones can be used, such as halogen, hypohalous acid, halous acid, perhalogenic acid, or salts thereof, halogen oxides, peroxides, etc.
  • sodium hypochlorite is preferred because it is inexpensive and has a low environmental impact.
  • the amount of the oxidizing agent used is, for example, preferably 0.5 to 500 mmol, more preferably 0.5 to 50 mmol, even more preferably 1 to 25 mmol, and most preferably 3 to 10 mmol, per 1 g of bone dry cellulose. Further, for example, it is preferably 1 to 40 mol per 1 mol of the N-oxyl compound.
  • the reaction temperature is preferably 4 to 40°C, and may be room temperature of about 15 to 30°C.
  • carboxy groups are generated in the cellulose, so a decrease in the pH of the reaction solution is observed.
  • an alkaline solution such as an aqueous sodium hydroxide solution to maintain the pH of the reaction solution at about 8 to 12, preferably about 10 to 11. Water is preferable as the reaction medium because of its ease of handling and the fact that side reactions are less likely to occur.
  • the reaction time in the oxidation reaction can be appropriately set according to the degree of progress of oxidation, and is usually about 0.5 to 6 hours, for example about 0.5 to 4 hours.
  • the oxidation reaction may be carried out in two stages. For example, by oxidizing the oxidized cellulose obtained by filtration after the completion of the first-stage reaction again under the same or different reaction conditions, the efficiency can be improved without being inhibited by the salt produced as a by-product in the first-stage reaction. Can be oxidized well.
  • Another example of the carboxylation (oxidation) method is a method of oxidizing a cellulose raw material by bringing it into contact with a gas containing ozone. This oxidation reaction oxidizes the hydroxyl groups at at least the 2- and 6-positions of the glucopyranose ring and causes decomposition of the cellulose chain.
  • the ozone concentration in the ozone-containing gas is preferably 50 to 250 g/m 3 , more preferably 50 to 220 g/m 3 .
  • the amount of ozone added to the cellulose raw material is preferably 0.1 to 30 parts by mass, more preferably 5 to 30 parts by mass, when the solid content of the cellulose raw material is 100 parts by mass.
  • the ozone treatment temperature is preferably 0 to 50°C, more preferably 20 to 50°C.
  • the ozone treatment time is not particularly limited, but is about 1 to 360 minutes, preferably about 30 to 360 minutes. When the ozone treatment conditions are within these ranges, excessive oxidation and decomposition of cellulose can be prevented, resulting in a good yield of oxidized cellulose.
  • additional oxidation treatment may be performed using an oxidizing agent.
  • the oxidizing agent used in the additional oxidation treatment is not particularly limited, but examples thereof include chlorine-based compounds such as chlorine dioxide and sodium chlorite, oxygen, hydrogen peroxide, persulfuric acid, and peracetic acid.
  • the additional oxidation treatment can be performed by dissolving these oxidizing agents in water or a polar organic solvent such as alcohol to prepare an oxidizing agent solution, and immersing the cellulose raw material in the solution.
  • the amount of carboxy groups in the oxidized cellulose can be adjusted by controlling the reaction conditions such as the amount of the oxidizing agent added and the reaction time.
  • Carboxymethyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose, or hydroxypropyl cellulose which are exemplified above as cellulose-based polymers obtained by anion modification, may be obtained by etherifying cellulose raw materials by a known method, or commercially available products. May be used.
  • Carboxymethyl cellulose or its salt For example, when obtaining carboxymethylcellulose or a salt thereof (hereinafter sometimes referred to as "CMC"), the method for producing carboxymethylcellulose or a salt thereof is not limited, and any known method for producing carboxymethylcellulose or a salt thereof may be applied. can. That is, after treating cellulose, which is a raw material, with a mercerizing agent (alkali) to prepare mercerized cellulose (alkali cellulose), an etherifying agent is added to cause an etherification reaction to produce carboxymethylcellulose or its salt in the present invention. can be manufactured.
  • a mercerizing agent alkali
  • any of the above-mentioned celluloses can be used without particular limitation, but those with high cellulose purity are preferred, and it is particularly preferred to use dissolving pulp and linters. By using these, highly pure carboxymethyl cellulose or a salt thereof can be obtained.
  • alkali metal hydroxide salts such as sodium hydroxide and potassium hydroxide can be used.
  • etherification agent monochloroacetic acid, monochloroacetic acid soda, etc. can be used.
  • the molar ratio of the mercerizing agent to the etherifying agent in the general production method of water-soluble carboxymethylcellulose is generally 2.00 to 2.45 when monochloroacetic acid is used as the etherifying agent. .
  • the reason for this is that if it is less than 2.00, the etherification reaction may not be carried out sufficiently, resulting in unreacted monochloroacetic acid remaining and being wasted; This is because there is a possibility that a side reaction between an excess of the mercerizing agent and monochloroacetic acid may proceed to produce an alkali metal salt of glycolic acid, which may be uneconomical.
  • carboxymethylcellulose or its salt may be used as it is, or after treatment if necessary.
  • Commercially available products include, for example, the trade name "Sunrose” (sodium salt of carboxymethyl cellulose) manufactured by Nippon Paper Industries, Ltd.
  • carboxymethylcellulose or salt thereof of the present invention has a degree of carboxymethyl substitution per anhydroglucose unit of 0.5 or more, more preferably 0.6 or more. If the degree of carboxymethyl substitution is less than 0.5, the solubility in water may be insufficient.
  • anhydroglucose units refer to individual anhydroglucoses (glucose residues) that constitute cellulose.
  • the degree of carboxymethyl substitution also referred to as the degree of etherification refers to the proportion of hydroxyl groups (-OH) in glucose residues constituting cellulose that are substituted with carboxymethyl ether groups (-OCH 2 COOH). show. Note that the degree of carboxymethyl substitution may be abbreviated as DS or CM-DS.
  • the upper limit of the degree of carboxymethyl substitution per anhydroglucose unit of carboxymethyl cellulose or its salt is preferably 1.2 or less, more preferably 1.0 or less.
  • the method for measuring the degree of substitution of carboxymethyl groups is as follows: Weigh approximately 2.0 g of the sample accurately and place it in a 300 mL Erlenmeyer flask with a stopper. Add 100 mL of a solution prepared by adding 100 mL of special grade concentrated nitric acid to 1000 mL of methanol, and shake for 3 hours to convert carboxymethyl cellulose salt (CMC) to H-CMC (hydrogen form carboxymethyl cellulose). Accurately weigh 1.5 to 2.0 g of the bone-dried H-CMC and place it in a 300 mL Erlenmeyer flask with a stopper.
  • CMC carboxymethyl cellulose salt
  • the CMC used in the present invention may be one type, or a combination of two or more types of CMC with different degrees of etherification, CM-DS, viscosity, molecular weight, etc. Viscosity will be described later.
  • the cellulose When using phosphoric acid esterified cellulose as a cellulose-based polymer obtained by anion modification, the cellulose can be prepared by mixing the powder or aqueous solution of phosphoric acid compound A with the cellulose raw material described above, or by adding phosphoric acid to a slurry of the cellulose raw material. It can be obtained by adding an aqueous solution of Compound A.
  • Examples of the phosphoric acid compound A include phosphoric acid, polyphosphoric acid, phosphorous acid, phosphonic acid, polyphosphonic acid, or esters thereof. These may be in the form of salts. Among these, compounds having a phosphoric acid group are preferred because they are low cost and easy to handle. Examples of compounds having a phosphoric acid group include phosphoric acid, sodium dihydrogen phosphate, disodium hydrogen phosphate, trisodium phosphate, sodium pyrophosphate, sodium metaphosphate, potassium dihydrogen phosphate, dipotassium hydrogen phosphate, and phosphoric acid.
  • Examples include tripotassium acid, potassium pyrophosphate, potassium metaphosphate, ammonium dihydrogen phosphate, diammonium hydrogen phosphate, triammonium phosphate, ammonium pyrophosphate, and ammonium metaphosphate. These can be used alone or in combination of two or more.
  • phosphoric acid, a sodium salt of phosphoric acid, a potassium salt of phosphoric acid, and an ammonium salt of phosphoric acid are more preferable from the viewpoint of high efficiency of introducing a phosphoric acid group and easy industrial application.
  • Particularly preferred are sodium dihydrogen phosphate and disodium hydrogen phosphate.
  • the phosphoric acid compound A in the form of an aqueous solution, since the uniformity of the reaction and the efficiency of introducing phosphoric acid groups are increased.
  • the pH of the aqueous solution of the phosphoric acid compound A is preferably 7 or less since this increases the efficiency of introducing phosphoric acid groups, but the pH is preferably 3 to 7 from the viewpoint of suppressing hydrolysis of pulp fibers.
  • a phosphoric acid compound A is added to a dispersion of a cellulose raw material having a solid content concentration of 0.1 to 10% by mass while stirring to introduce phosphoric acid groups into the cellulose.
  • the amount of phosphoric acid compound A added is preferably 0.2 to 500 parts by mass, more preferably 1 to 400 parts by mass as the amount of phosphorus element. If the proportion of phosphoric acid compound A is equal to or higher than the lower limit, the yield of fine fibrous cellulose can be further improved. However, if the above upper limit is exceeded, the effect of improving the yield reaches a ceiling, which is not preferable from a cost standpoint.
  • compound B is not particularly limited, but is preferably a nitrogen-containing compound that exhibits basicity.
  • “Basic” herein is defined as the aqueous solution exhibiting a pink to red color in the presence of the phenolphthalein indicator, or the pH of the aqueous solution being greater than 7.
  • the basic nitrogen-containing compound used in the present invention is not particularly limited as long as it exhibits the effects of the present invention, but compounds having an amino group are preferred.
  • Examples include, but are not limited to, urea, methylamine, ethylamine, trimethylamine, triethylamine, monoethanolamine, diethanolamine, triethanolamine, pyridine, ethylenediamine, and hexamethylenediamine.
  • urea is preferred because it is low cost and easy to handle.
  • the amount of compound B added is preferably 2 to 1000 parts by weight, more preferably 100 to 700 parts by weight, based on 100 parts by weight of the solid content of the cellulose raw material.
  • the reaction temperature is preferably 0 to 95°C, more preferably 30 to 90°C.
  • the reaction time is not particularly limited, but is approximately 1 to 600 minutes, more preferably 30 to 480 minutes.
  • cellulose can be prevented from being excessively esterified and easily dissolved, and the yield of phosphoric acid esterified cellulose can be improved.
  • After dehydrating the obtained phosphoric acid esterified cellulose suspension it is preferably heat-treated at 100 to 170° C. from the viewpoint of suppressing hydrolysis of cellulose. Further, during heat treatment, it is preferable to heat at 130° C. or lower, preferably 110° C. or lower while water is contained, and after removing water, heat treatment at 100 to 170° C.
  • the degree of phosphoric acid group substitution per glucose unit of the phosphoric acid esterified cellulose is preferably 0.001 to 0.40.
  • a cationically modified cellulose polymer As the chemically modified cellulose polymer, cellulose obtained by further cationizing the carboxylated cellulose can be used.
  • the cationically modified cellulose is produced by adding a cationizing agent such as glycidyltrimethylammonium chloride, 3-chloro-2-hydroxypropyltrialkylammonium halide or its halohydrin type to the carboxylated cellulose raw material, and an alkali metal hydroxide as a catalyst. (sodium hydroxide, potassium hydroxide, etc.) in the presence of water or an alcohol having 1 to 4 carbon atoms.
  • the degree of cation substitution per glucose unit is preferably 0.02 to 0.50.
  • the degree of cation substitution can be adjusted by adjusting the amount of the cationizing agent to be reacted and the composition ratio of water or alcohol having 1 to 4 carbon atoms.
  • the viscosity of a 1% by mass aqueous solution of the chemically modified cellulose polymer to be pulverized at 25°C as measured by a B-type viscometer (30 rpm) is preferably 1,000 to 20,000 mPa ⁇ s, or more. It is preferably 1,500 to 15,000 mPa ⁇ s, more preferably 1,500 to 10,000 mPa ⁇ s.
  • the viscosity measurement method is as follows: A chemically modified cellulose polymer to be crushed is measured into a 1000 mL glass beaker and dispersed in 900 mL of distilled water to prepare an aqueous dispersion with a solid content of 1% (w/v). The aqueous dispersion is stirred at 25° C. using a stirrer at 600 rpm for 3 hours. Thereafter, according to the method of JIS-Z-8803, using a B-type viscometer (manufactured by Toki Sangyo Co., Ltd.), No. Measure the viscosity after 3 minutes with 4 rotors/30 rpm.
  • the unmodified pulp is not particularly limited, but it is preferable to use powdered cellulose using unmodified pulp.
  • powdered cellulose using unmodified pulp include those obtained by mechanically crushing pulp or acid hydrolyzing it to powder.
  • the method for producing powdered cellulose is not particularly limited as long as it is a method for obtaining powdered cellulose from a cellulose raw material, but examples include a method that includes at least a pulverization process, and it is easy to obtain powdered cellulose with few impurities. A method in which an acid hydrolysis treatment is further performed is preferred.
  • the cellulose raw materials include those mentioned above, but it is preferable to use pulp, and pulp derived from wood is more preferable.
  • pulp derived from wood include pulp derived from broad-leaved trees and pulp derived from coniferous trees.
  • Examples of the method for preparing wood-derived pulp include a method including a treatment using a pulping method (cooking method).
  • the pulping method dissolves and removes the colored substance lignin, making it possible to obtain pulp with a high degree of whiteness.
  • the pulping method (cooking method) include sulfite cooking, kraft cooking, soda quinone cooking, and organosolve cooking, with kraft pulp being preferred from an environmental standpoint.
  • Bleaching treatment methods include, for example, chlorine treatment (C), chlorine dioxide bleaching (D), alkali extraction (E), hypochlorite bleaching (H), Hydrogen peroxide bleaching (P), alkaline hydrogen peroxide treatment stage (Ep), alkaline hydrogen peroxide/oxygen treatment stage (Eop), ozone treatment (Z), chelation treatment (Q), and two or more of these treatments.
  • chlorine treatment C
  • chlorine dioxide bleaching D
  • alkali extraction E
  • hypochlorite bleaching H
  • Hydrogen peroxide bleaching P
  • alkaline hydrogen peroxide treatment stage Ep
  • alkaline hydrogen peroxide/oxygen treatment stage Eop
  • Z ozone treatment
  • Q chelation treatment
  • Examples of combinations (sequences) of two or more processes include D-E/P-D, C/D-E-HD, Z-E-D-PZ/D-Ep-D, and Z/D- Ep-DP, D-Ep-D, D-Ep-DP, D-Ep-PD, Z-Eop-DD, Z/D-Eop-D, Z/D-Eop-D- ED (the "/" in the sequence means that the processes before and after the "/" are performed consecutively without washing).
  • Bleaching treatment is not limited to the above example, and may be any commonly used method. Pulp that has undergone bleaching treatment is usually in a fluid state (fluid pulp). The whiteness of the pulp is preferably 80% or more based on ISO 2470.
  • acids used in the acid hydrolysis treatment include mineral acids such as hydrochloric acid, sulfuric acid, and nitric acid.
  • the acid concentration is not particularly limited, but from the viewpoint of maintaining the degree of polymerization and whiteness, it is preferably lower than the acid concentration in the conventional acid hydrolysis treatment for producing powdered cellulose, and is preferably 0.4 to 2.0N. More preferably, 0.5 to 1.5N is more preferable.
  • the acid concentration is less than 0.4N, depolymerization of cellulose due to acid is suppressed and a decrease in the degree of polymerization of cellulose can be reduced, but it may be difficult to refine the cellulose.
  • reaction conditions for the acid hydrolysis treatment are not particularly limited, but the reaction temperature is usually 80 to 100°C, and the reaction time is usually 30 minutes to 3 hours.
  • the cellulose raw material Prior to the acid hydrolysis treatment, the cellulose raw material may be pretreated. Examples include slurrying the cellulose raw material (preparation of a dispersion) and adjusting the concentration of the cellulose raw material. The concentration of the cellulose raw material is usually 3 to 10% by weight (based on solid content) based on the dispersion.
  • a treatment to increase the pulp density is usually performed before hydrolysis.
  • a dehydrator such as a screw press or a belt filter may be used to adjust (concentrate) the cellulose raw material concentration.
  • the acid hydrolysis treatment may be performed on a slurry of cellulose raw material, or may be performed on a sheet-shaped cellulose raw material. When the cellulose raw material is a dry sheet of pulp, the acid hydrolysis treatment is usually performed after the pulp is loosened. When loosening the pulp, a crusher such as a roll crusher may be used.
  • the neutralization treatment may be performed by adding an alkaline agent.
  • the deliquid treatment is usually a solid-liquid separation treatment, and waste acid can be separated from the hydrolyzed product.
  • the hydrolyzate may undergo a drying (dehydration) treatment.
  • the solid content concentration can be adjusted and the physical properties of the powdered cellulose can be easily controlled.
  • the solid content concentration is usually adjusted to 15% or more, preferably 20% or more.
  • a flash dryer For drying, it is preferable to use a flash dryer. As a result, regardless of whether the processed material after hydrolysis is a cake-like solid, slurry, solution, etc., it is possible to apply high-speed hot air to the product while dispersing it in the air stream, and also to utilize the depressurizing effect inside the dryer. It can be dried instantly. In addition, since the exposure time to hot air is extremely short, the product temperature can be kept low, making it ideal for drying products that are sensitive to heat or products with low melting points.
  • the conditions for drying using a flash dryer are not particularly limited and can be set as appropriate, but an example is as follows.
  • the outlet drying temperature is usually 80 to 180°C, preferably 90 to 160°C.
  • the amount of air supplied is usually 150 to 350 m 3 /h, preferably 160 to 320 m 3 /h.
  • the product is sprayed and instantly dried with hot air to produce granules. Therefore, it is often not suitable for drying solid or semi-solid objects with low moisture content, and the particles are more likely to be exposed to high heat instantaneously than when drying with a flash dryer, which may affect the product. be done.
  • the unmodified pulp may be pulverized by mechanically pulverizing the processed material that has undergone the previous step.
  • a classification process may be performed simultaneously with the pulverization or after the pulverization.
  • the crusher used for the powdering treatment of unmodified pulp can be used without any particular restrictions, but examples include a jaw crusher (manufactured by Makino Co., Ltd.), a pulverizer (manufactured by Hosokawa Micron Co., Ltd.), a super micron mill (manufactured by Hosokawa Micron Co., Ltd.), Tornado mill (manufactured by Nikkiso Co., Ltd.), Jiyu crusher (manufactured by Nara Kikai Seisakusho Co., Ltd.), Turbo mill (manufactured by Freund Sangyo Co., Ltd.), Spar powder mill (manufactured by Nishimura Kikai Seisakusho Co., Ltd.), Blade mill (Nissin Engineering Co., Ltd.) It is preferable to use a supersonic jet mill (manufactured by Nippon Pneumatic Industries Co., Ltd.), or a current jet (manufactured by Nisshin Engineering Co.,
  • the conditions for the powdering treatment of the unmodified pulp or the classification treatment performed as necessary can be appropriately set so as to obtain the desired powdered cellose.
  • the processing conditions can be adjusted with reference to a calibration curve created from the pulverization conditions (eg, processing time, input amount) and desired physical properties of the powdered cellulose.
  • At least one other component for example, an organic component, an inorganic component
  • the pulverization treatment together with the acid-hydrolyzed product, if necessary.
  • functionality can be imparted to the powdered cellulose or the functionality can be improved.
  • the amounts of other components to be blended may be appropriately selected.
  • chemical treatment may be performed as necessary.
  • any treatment that does not pose a risk of significantly impairing the degree of polymerization of the cellulose raw material can be selected as appropriate.
  • the timing of the chemical treatment includes, for example, before the acid hydrolysis treatment and at the same time as the pulverization treatment, but is not particularly limited.
  • a bead mill usually has a grinding container called a vessel, a large number of beads as grinding media filled in the vessel, and an agitator that stirs the beads by high-speed rotation.
  • the material to be pulverized is placed in a vessel, and the agitator rotates at high speed to agitate the beads, causing the beads to collide with each other, the beads and the inner wall of the vessel, and the beads and the agitator, respectively.
  • the agitator rotates at high speed to agitate the beads, causing the beads to collide with each other, the beads and the inner wall of the vessel, and the beads and the agitator, respectively.
  • objects to be crushed existing in the gaps between the beads, the gaps between the beads and the inner wall of the vessel, and the gaps between the beads and the agitator are crushed by shearing force, impact force, frictional force, etc.
  • the type of agitator is not particularly limited, and a disk type, pin type, annular gap type, etc. can be adopted. Further, there is no particular restriction on the orientation of the vessel, and a vertical or horizontal type can be adopted.
  • the material of the beads and/or vessels can be used without any particular restriction as long as it has high hardness and is resistant to wear.
  • examples of the stabilized zirconia include yttria-stabilized zirconia, magnesia-stabilized zirconia, calcia-stabilized zirconia, ceria-stabilized zirconia, and examples of the partially-stabilized zirconia include yttria-stabilized zirconia and magnesia-stabilized zirconia. Examples include zirconia, calcia partially stabilized zirconia, and ceria partially stabilized zirconia.
  • a wet bead mill or a dry bead mill can be used without any particular restriction, but it is preferable to use a dry bead mill.
  • examples of the dry bead mill include Dynamic Mill (manufactured by Nippon Coke Industry Co., Ltd.), Dry Star (manufactured by Ashizawa Finetech Co., Ltd.), and the like.
  • the classification method is not particularly limited, but a method using a dry classifier is preferred.
  • a method using a dry classifier is preferred.
  • the dry classification it is preferable to perform airflow classification.
  • the coarse powder that has been subjected to the classification treatment is pulverized again using a bead mill.
  • FIG. 1 is a schematic diagram showing an example of a crushing device including a bead mill used in the present invention.
  • the pulverizing device 2 includes a bead mill 4 for pulverizing a cellulose polymer as a raw material (material to be pulverized), and a classifier 6 for classifying the cellulose polymer pulverized by the bead mill 4.
  • the bead mill 4 and the classifier 6 are connected by a connecting part 8.
  • the cellulose-based polymer (fine powder) having a particle size less than a predetermined value, which has been crushed by the bead mill 4 and classified by the classifier 6, is collected in a product collection section 10 that includes a bag filter or the like.
  • a blower 11 is provided downstream of the product recovery section 10.
  • the arrows in FIG. 1 indicate the direction of movement of the cellulosic polymer and/or air.
  • the bead mill 4 is equipped with a vessel 12 which is a crushing container, and inside the vessel 12 is equipped with an agitator 14 which is arranged horizontally and is configured to be rotatable by a drive device (not shown), and a large number of beads 16 as crushing media. Further, a raw material supply section 18 is provided in the vessel 12 for supplying a cellulose-based polymer as a raw material to be crushed. In addition, what is illustrated by a circle in the vessel 12 indicates a bead even if no code is attached thereto. Note that the crushing device 2 is configured so that the beads 16 do not flow into the classifier 6 through the connection portion 8 or the coarse powder recovery port 22, nor flow into the raw material supply portion 18.
  • the classifier 6 has a product recovery port 20 for sending the classified cellulose polymer (fine powder) to the product recovery section 10, and a product recovery port 20 for sending the cellulose polymer (coarse powder) having a particle size of a predetermined value or more to the vessel 12.
  • a coarse powder collection port 22 is provided.
  • the process of pulverizing cellulose polymer will be explained.
  • the bead mill 4 starts rotating the agitator 14 by a drive device (not shown). Further, the blower 11 is also activated. As the agitator 14 rotates, the beads 16 are agitated.
  • the cellulose-based polymer as a material to be crushed When the cellulose-based polymer as a material to be crushed is supplied from the raw material supply section 18 into the vessel 12, it is crushed by the beads 16 that are being stirred in the vessel 12. That is, by stirring the beads 16, collisions occur between the beads 16, collisions between the beads 16 and the inner wall of the vessel 12, and collisions between the beads 16 and the agitator 14. As a result of this collision, the cellulose-based polymer that is the object to be crushed, which exists in the gaps between the beads, the gaps between the beads and the inner wall of the vessel, and the gaps between the beads and the agitator, is crushed by shear force, impact force, frictional force, etc. Ru.
  • the cellulose-based polymer pulverized in the vessel 12 is sent to the classifier 6 via the connection part 8. Then, classification is performed by the classifier 6, and the cellulose polymer (fine powder) having a particle size smaller than a predetermined value is sent to the product recovery section 10 via the product recovery port 20. Further, the cellulose-based polymer (coarse powder) having a particle diameter of a predetermined value or more is supplied to the vessel 12 of the bead mill 4 through the coarse powder collection port 22 and subjected to a pulverization process by the bead mill 4 .
  • the average diameter (bead diameter) of the beads used in the bead mill is 0.1 to 10 mm, preferably 3 to 8 mm. If the particle size of the beads is too large, a problem arises in that the particle size of the obtained sample becomes large. Furthermore, if the particle size of the beads is too small, a problem arises in that the viscosity of the sample obtained becomes low.
  • the filling rate of beads filled in the vessel is 50 to 90 vol%, preferably 70 to 90 vol%. If the filling rate of beads is too large, a problem arises in that contamination is likely to occur. Moreover, if the filling rate of beads is too small, there will be a problem that productivity will be low.
  • the peripheral speed of the agitator is 2 to 15 m/sec, preferably 6 to 15 m/sec. If the circumferential speed of the agitator is too high, a problem arises in that the viscosity of the sample obtained becomes low. Further, if the circumferential speed of the agitator is too slow, a problem arises in that the particle size of the sample obtained becomes large.
  • the amount of cellulose polymer supplied from the raw material supply section 18 is preferably 30 to 150 kg/h, more preferably 40 to 120 kg/h. If the supply amount is too large, a problem arises in that the particle size of the obtained sample becomes large. Furthermore, if the supply amount is too small, a problem arises in that the viscosity of the sample obtained becomes low.
  • the particle diameter indicates the maximum particle diameter (D max ) determined by a grain gauge (grind gauge). Specifically, it is the maximum particle diameter (D max ) determined from the dispersity of the linear method measured with a grind gauge in accordance with JIS K5600 and JIS K5400 (1990).
  • a chemically modified cellulose polymer when used as the cellulose polymer, a 1% by mass aqueous solution of the cellulose polymer after pulverization with a bead mill at 25°C measured with a B-type viscometer (30 rpm)
  • the viscosity is preferably 500 to 15,000 mPa ⁇ s, more preferably 800 to 13,000 mPa ⁇ s, and still more preferably 1,000 to 10,000 mPa ⁇ s. Note that the viscosity of the cellulose polymer after being pulverized by a bead mill can be measured in the same manner as the method for measuring the viscosity of the cellulose polymer to be pulverized described above.
  • the ratio of mass M to mass m is preferably less than 50 ppm. If it is 50 ppm or more, when a film is formed using a cellulose polymer, appearance defects such as streaks and pinholes may occur in the film, and the quality of products using the film may deteriorate.
  • the lower limit of the ratio of the mass M to the mass m is not particularly limited, and the smaller the ratio, the better.
  • the cellulose-based polymer to be pulverized may be pre-pulverized.
  • an impact mill can be used, although it is not particularly limited.
  • Impact mills include Pulperizer (manufactured by Hosokawa Micron Co., Ltd.), Fine Impact Mill (manufactured by Hosokawa Micron Co., Ltd.), Super Micron Mill (manufactured by Hosokawa Micron Co., Ltd.), Sample Mill (manufactured by Seishin Co., Ltd.), and Bantam Mill (manufactured by Seishin Co., Ltd.).
  • Examples include Seishin Co., Ltd.), an atomizer (Seishin Co., Ltd.), a tornado mill (Nikkiso Co., Ltd.), a turbo mill (Turbo Kogyo Co., Ltd.), and a bevel impactor (Aikawa Tekko Co., Ltd.).
  • the use of the pulverized cellulose-based polymer obtained by the cellulose-based polymer pulverization method of the present invention is not particularly limited, and can be applied to various uses.
  • thickeners thickeners, gelling agents, sizing agents, food additives, excipients, paint additives, adhesive additives, paper manufacturing additives, abrasives, compounded materials for rubber and plastics, water retention agents, It can be used as a filler, mud water conditioner, filter aid, mud flooding prevention agent, etc.
  • the pulverized cellulose polymer obtained by the cellulose polymer pulverization method of the present invention can be used as a binder for the positive electrode and/or negative electrode of a nonaqueous electrolyte secondary battery such as a lithium ion secondary battery.
  • the above-mentioned positive electrode and/or negative electrode can be formed by laminating an electrode composition on a current collector by blade coating, bar coating, die coating, etc., and then heating, drying, pressurizing, etc.
  • the electrode composition contains an electrode active material, a binder, and other components such as a conductive material as necessary, and as a binder, a pulverized cellulose polymer obtained by the cellulose polymer pulverization method of the present invention is used. Can be used.
  • the manufacturing conditions for the electrode composition are not particularly limited, but for example, other components constituting the electrode composition are added to the above-mentioned aqueous solution or dispersion of the pulverized cellulose-based polymer, and if necessary, while stirring. Obtained by mixing.
  • the properties of the electrode composition are not particularly limited, and may be any of liquid, paste, and slurry forms.
  • the electrode active material in the electrode composition includes a positive electrode active material or a negative electrode active material.
  • the positive electrode active material is preferably a LiMe x O y (Me means a transition metal containing at least one of Ni, Co, and Mn. x and y represent arbitrary numbers) type positive electrode active material, LiCoO 2 or the like can be preferably used.
  • Examples of negative electrode active materials include graphite materials such as graphite (natural graphite, artificial graphite), coke, and carbon fiber; elements that can form an alloy with lithium (for example, Al, Si, Sn, Ag, Bi , Mg, Zn, In, Ge, Pb, Ti, etc.); a composite of an element capable of forming an alloy with lithium and the compound, and carbon and/or the graphitic material; Nitrides containing nitrides, etc. can be used.
  • graphite materials and/or silicon-based compounds are preferable, it is more preferable that graphite and/or silicon-based compounds are included, and it is preferable that at least a silicon-based compound is included.
  • a pulverized cellulose polymer obtained by the cellulose polymer pulverization method of the present invention and a rubber binder such as styrene butadiene rubber (SBR) may be used in combination, if necessary.
  • the conductive material one that can ensure electrical conductivity of the positive electrode and/or negative electrode can be used.
  • the conductive material include one or a mixture of two or more carbon substances such as carbon black, acetylene black, and graphite.
  • any electrical conductor that does not cause a fatal chemical change in the constructed battery can be used.
  • the current collector for the negative electrode active material stainless steel, nickel, copper, titanium, carbon, copper, or stainless steel whose surface is coated with carbon, nickel, titanium, or silver can be used. Among these, copper or copper alloy is preferred, and copper is more preferred.
  • the material for the current collector for the positive electrode include metals such as aluminum and stainless steel, with aluminum being preferred.
  • As the shape of the current collector a net, punched metal, foam metal, foil processed into a plate shape, etc. can be used, and foil processed into a plate shape is preferable.
  • a non-aqueous electrolyte secondary battery such as a lithium ion secondary battery has a structure in which positive electrodes and negative electrodes are alternately stacked with separators interposed therebetween and wound many times.
  • An electrode containing as a binder a pulverized cellulose-based polymer obtained by the cellulose-based polymer pulverization method described above can be used.
  • the separator is usually impregnated with a nonaqueous electrolyte.
  • each index for carboxymethylcellulose or its salt as a cellulose-based polymer was measured by the following method.
  • CM-DS degree of carboxymethyl substitution
  • CM-DS was calculated by the following formula 1.
  • ⁇ Viscosity> A cellulose-based polymer was measured into a 1000 mL glass beaker and dispersed in 900 mL of distilled water to prepare an aqueous dispersion with a solid content of 1% (w/v). The aqueous dispersion was stirred at 25° C. using a stirrer at 600 rpm for 3 hours. Thereafter, according to the method of JIS-Z-8803, using a B-type viscometer (manufactured by Toki Sangyo Co., Ltd.), No. The viscosity was measured after 3 minutes using 4 rotors/30 rpm.
  • ⁇ Particle size (grain gauge)> The particle size was measured using a grain gauge (grind gauge). Specifically, the maximum particle diameter (D max ) was determined by the dispersity of the linear method measured using a grind gauge in accordance with JIS K5600 and JIS K5400 (1990).
  • Example 1 1161 g of isopropyl alcohol and 121 g of sodium hydroxide dissolved in 231 g of water were added to a twin-screw kneader whose rotational speed was adjusted to 100 rpm, and the dry mass of linter pulp (160 g when dried at 100° C. for 60 minutes) was charged. After stirring and mixing at 30°C for 90 minutes to prepare mercerized cellulose, a solution of 124 g of monochloroacetic acid in 142 g of isopropyl alcohol was added, and the mixture was heated to 70°C to carry out a carboxymethylation reaction for 90 minutes.
  • CMC1 carboxymethyl cellulose
  • the obtained CMC1 was pulverized using a pulverizer including a bead mill shown in FIG.
  • a pulverizer including a bead mill shown in FIG.
  • zirconia beads with a bead diameter of 5 mm were used at a filling rate of 80 vol%, and the peripheral speed of the agitator 14 was set to 10 m/sec.
  • the amount of CMC1 supplied into the vessel 12 of the bead mill 4 was 120 kg/h.
  • the viscosity of the 1 mass % aqueous solution of CMC1 after pulverization was 3,300 mPa ⁇ s, and the maximum particle diameter (D max ) determined by a particle gauge was 43 ⁇ m.
  • Example 2 Same as Example 1 except that the bead diameter was changed to 8 mm, the peripheral speed of the agitator 14 was changed to 8 m/sec, and the amount of CMC 1 supplied into the vessel 12 of the bead mill 4 was changed to 40 kg/h. CMC1 was pulverized.
  • the viscosity of a 1% by mass aqueous solution of CMC1 after pulverization at 25° C. measured with a B-type viscometer was 3,300 mPa ⁇ s, and the maximum particle diameter (D max ) determined by a particle gauge was 45 ⁇ m.
  • Example 3 1201 g of isopropyl alcohol and 101 g of sodium hydroxide dissolved in 255 g of water were added to a twin-screw kneader whose rotation speed was adjusted to 100 rpm, and the dry mass of linter pulp (160 g when dried at 100° C. for 60 minutes) was charged. After stirring and mixing at 30°C for 90 minutes to prepare mercerized cellulose, a solution of 104 g of monochloroacetic acid in 118 g of isopropyl alcohol was added, and the mixture was heated to 70°C to carry out a carboxymethylation reaction for 90 minutes.
  • CMC2 carboxymethyl cellulose
  • the obtained CMC2 was pulverized using a pulverizer including a bead mill shown in FIG.
  • a pulverizer including a bead mill shown in FIG.
  • zirconia beads with a bead diameter of 3 mm were used at a filling rate of 85 vol%, and the peripheral speed of the agitator 14 was set to 10 m/sec.
  • the amount of CMC1 supplied into the vessel 12 of the bead mill 4 was 60 kg/h.
  • the viscosity of the 1 mass % aqueous solution of CMC2 after pulverization was 8,420 mPa ⁇ s, and the maximum particle diameter (D max ) determined by a particle gauge was 37 ⁇ m.
  • Example 4 1201 g of isopropyl alcohol and 101 g of sodium hydroxide dissolved in 255 g of water were added to a twin-screw kneader whose rotation speed was adjusted to 100 rpm, and the dry mass of linter pulp (160 g when dried at 100° C. for 60 minutes) was charged. After stirring and mixing at 40° C. for 120 minutes to prepare mercerized cellulose, a solution of 104 g of monochloroacetic acid dissolved in 118 g of isopropyl alcohol was added, and the mixture was heated to 70° C. to carry out a carboxymethylation reaction for 90 minutes.
  • CMC3 carboxymethyl cellulose having a maximum particle diameter (D max ) determined by a gauge of more than 100 ⁇ m was obtained.
  • the obtained CMC3 was pulverized using a pulverizer including a bead mill shown in FIG.
  • a pulverizer including a bead mill shown in FIG.
  • zirconia beads with a bead diameter of 5 mm were used at a filling rate of 75 vol%, and the peripheral speed of the agitator 14 was set to 12 m/sec.
  • the amount of CMC1 supplied into the vessel 12 of the bead mill 4 was 85 kg/h.
  • the viscosity of a 1% by mass aqueous solution of CMC3 after pulverization at 25° C. measured with a B-type viscometer was 8,800 mPa ⁇ s, and the maximum particle diameter (D max ) determined by a particle gauge was 45 ⁇ m.
  • Example 1 CMC1 was pulverized in the same manner as in Example 1, except that the bead diameter was changed to 12 mm, the filling rate was changed to 60 vol%, and the peripheral speed of the agitator 14 was changed to 5 m/sec.
  • a method for pulverizing cellulose-based polymers using a bead mill wherein the beads used in the bead mill have an average diameter of 0.1 to 10 mm, the peripheral speed of the agitator of the bead mill is 2 to 15 m/sec, and the bead mill
  • the beads used in the bead mill have an average diameter of 0.1 to 10 mm
  • the peripheral speed of the agitator of the bead mill is 2 to 15 m/sec
  • the bead mill When a cellulose-based polymer was pulverized using a cellulose-based polymer pulverization method with a bead filling rate of 50 to 90 vol%, it was possible to stably produce a cellulose-based polymer with a particle size of less than 50 ⁇ m.

Landscapes

  • Engineering & Computer Science (AREA)
  • Food Science & Technology (AREA)
  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Polysaccharides And Polysaccharide Derivatives (AREA)

Abstract

[Problem] To provide a method for grinding a cellulose polymer, the method being capable of stably producing a cellulose polymer that has a particle diameter of less than 50 µm. [Solution] A method for grinding a cellulose polymer by means of a bead mill 4, wherein: the average diameter of beads 16 that are used for the bead mill is 0.1 mm to 10 mm; the peripheral velocity of an agitator 14 of the bead mill is 2 m/sec to 15 m/sec; and the bead filling rate of the bead mill is 50 vol% to 90 vol%.

Description

セルロース系ポリマーの粉砕方法Grinding method for cellulose polymer
　本発明は、セルロース系ポリマーの粉砕方法に関するものである。 The present invention relates to a method for pulverizing cellulose polymers.
　セルロース系ポリマーとして、カルボキシメチルセルロース等のセルロース系ポリマーは、安全性の高さの観点等の理由から様々な分野に利用され、また利用が検討されている。 As cellulose-based polymers, cellulose-based polymers such as carboxymethylcellulose are used in various fields for reasons such as high safety, and their use is being considered.
　たとえば、カルボキシメチルセルロース又はその塩（以下、「ＣＭＣ」ということがある。）は、セルロースの骨格を構成するグルコピラノースモノマーのヒドロキシ基の一部にカルボキシメチル基を結合させたもの、またはカルボキシメチル基が塩になっているものである。 For example, carboxymethylcellulose or a salt thereof (hereinafter sometimes referred to as "CMC") is a product in which a carboxymethyl group is bonded to a part of the hydroxyl group of a glucopyranose monomer that constitutes the cellulose skeleton, or a carboxymethyl group is salt.
　ＣＭＣの品質（増粘性・吸水性・保水性）はカルボキシメチル基の置換度、セルロース骨格の長さなどにより調整することができ、化粧品、医薬品、食品、各種工業製品などの増粘剤、粘結剤、バインダー、吸水材、保水剤、乳化安定剤などとして使用されている。また、天然セルロース由来であるため、緩やかな生分解性を有するとともに焼却廃棄が可能である環境に極めてやさしい素材であり、ＣＭＣの用途は今後拡大されると予測されている。 The quality of CMC (thickening ability, water absorption, and water retention) can be adjusted by adjusting the degree of substitution of carboxymethyl groups, the length of the cellulose skeleton, etc. It is used as a binding agent, binder, water absorbing material, water retaining agent, emulsion stabilizer, etc. In addition, since it is derived from natural cellulose, it is an extremely environmentally friendly material that has gradual biodegradability and can be disposed of by incineration, and it is predicted that the applications of CMC will expand in the future.
　しかし、特許文献１には、たとえば、非水二次電池の電極活物質を集電体に密着させるための結着剤用途とした場合、カルボキシメチルセルロースを用いるよりもセルロースファイバーが良いことが記載されているなど、セルロース系ポリマーは用途が限定されることがあった。 However, Patent Document 1 describes that cellulose fiber is better than carboxymethyl cellulose when used as a binder for adhering the electrode active material of a non-aqueous secondary battery to a current collector, for example. The applications of cellulose-based polymers have been limited due to
　本発明者らの検討によれば、セルロース系ポリマーの所定の方法により求められ粒子径が５０μｍ未満であると、用途を限定することなく使い勝手が良いことが判明した。 According to studies by the present inventors, it has been found that cellulose-based polymers with a particle diameter of less than 50 μm determined by a predetermined method are easy to use without limiting the application.
特開２０１７－１３０４５１号公報JP 2017-130451 Publication
　本発明の目的は粒子径が５０μｍ未満のセルロース系ポリマーを安定して製造すること
のできるセルロース系ポリマーの粉砕方法を提供することである。 An object of the present invention is to provide a method for pulverizing cellulose polymers that can stably produce cellulose polymers having a particle size of less than 50 μm.
　本発明者らは、鋭意検討の結果、所定の条件により粉砕を行うことにより上記目的を達
成できることを見出し、上記課題を解決できることを見出した。 As a result of intensive studies, the present inventors discovered that the above object could be achieved by performing pulverization under predetermined conditions, and found that the above problems could be solved.
　すなわち、本発明によれば、
（１）　ビーズミルによるセルロース系ポリマーの粉砕方法であって、前記ビーズミルに用いるビーズの平均直径が０．１～１０ｍｍ、前記ビーズミルのアジテータの周速が２～１５ｍ／ｓｅｃ、前記ビーズミルのビーズ充填率が５０～９０ｖｏｌ％であるセルロース系ポリマーの粉砕方法、
（２）　前記ビーズの平均直径が３～８ｍｍである（１）記載のセルロース系ポリマーの粉砕方法、
（３）　前記ビーズミルは乾式ビーズミルである（１）または（２）記載のセルロース系ポリマーの製造方法、
（４）　前記ビーズミルの前記アジテータおよび／またはベッセルの材質は、ジルコニア、ジルコン、安定化ジルコニア、部分安定化ジルコニア、アルミナまたは窒化ケイ素のうちから選ばれる少なくとも１つである（１）または（２）記載のセルロース系ポリマーの粉砕方法、
（５）　前記ビーズミルへの前記セルロース系ポリマーの供給量が３０～１５０ｋｇ／ｈである、（１）または（２）に記載のセルロース系ポリマーの粉砕方法、
（６）　前記セルロース系ポリマーが、カルボキシメチルセルロースおよび／又はその塩である、（１）または（２）に記載のセルロース系ポリマーの粉砕方法
が提供される。 That is, according to the present invention,
(1) A method of pulverizing a cellulose polymer using a bead mill, wherein the average diameter of the beads used in the bead mill is 0.1 to 10 mm, the peripheral speed of the agitator of the bead mill is 2 to 15 m/sec, and the bead filling rate of the bead mill is A method for pulverizing a cellulose-based polymer in which the amount is 50 to 90 vol%,
(2) The method for pulverizing a cellulose polymer according to (1), wherein the beads have an average diameter of 3 to 8 mm;
(3) The method for producing a cellulose polymer according to (1) or (2), wherein the bead mill is a dry bead mill;
(4) The material of the agitator and/or vessel of the bead mill is at least one selected from zirconia, zircon, stabilized zirconia, partially stabilized zirconia, alumina, or silicon nitride (1) or (2) The method for pulverizing cellulose polymers described above;
(5) The method for pulverizing a cellulose-based polymer according to (1) or (2), wherein the amount of the cellulose-based polymer supplied to the bead mill is 30 to 150 kg/h.
(6) There is provided the method for pulverizing a cellulose-based polymer according to (1) or (2), wherein the cellulose-based polymer is carboxymethyl cellulose and/or a salt thereof.
　本発明によれば、粒子径が５０μｍ未満のセルロース系ポリマーを安定して製造することのできるセルロース系ポリマーの粉砕方法を提供することができる。 According to the present invention, it is possible to provide a method for pulverizing a cellulose-based polymer that can stably produce a cellulose-based polymer having a particle size of less than 50 μm.
本発明に用いるビーズミルを含む粉砕装置の一例を示す概略図である。1 is a schematic diagram showing an example of a crushing device including a bead mill used in the present invention.
　以下、本発明のセルロース系ポリマーの粉砕方法について説明する。本発明のセルロース系ポリマーの粉砕方法は、ビーズミルによるセルロース系ポリマーの粉砕方法であって、前記ビーズミルに用いるビーズの平均直径が０．１～１０ｍｍ、前記ビーズミルのアジテータの周速が２～１５ｍ／ｓｅｃ、前記ビーズミルのビーズ充填率が５０～９０ｖｏｌ％である。 Hereinafter, the method for pulverizing cellulose polymer of the present invention will be explained. The method for pulverizing cellulose polymers of the present invention is a method for pulverizing cellulose polymers using a bead mill, wherein the beads used in the bead mill have an average diameter of 0.1 to 10 mm, and the peripheral speed of the agitator of the bead mill is 2 to 15 m/min. sec, the bead filling rate of the bead mill is 50 to 90 vol%.
　（セルロース系ポリマー）
　本発明において、粉砕対象とするセルロース系ポリマーとしては、セルロース由来の化合物であれば、特に制限なく用いることができるが、化学変性されたセルロース系ポリマー、未変性パルプを用いることが好ましい。 (cellulose polymer)
In the present invention, as the cellulose-based polymer to be pulverized, any compound derived from cellulose can be used without particular limitation, but it is preferable to use a chemically modified cellulose-based polymer or unmodified pulp.
　セルロース系ポリマーは、セルロースを原料として得ることができる。すなわち、本発明においてセルロース原料として用いることができるセルロースとは、Ｄ－グルコピラノース（単に「グルコース残基」、「無水グルコース」とも言う。）がβ，１－４結合で連なった構造の多糖を意味する。セルロースは、一般に起源、製法等から、天然セルロース、再生セルロース、微細セルロース、非結晶領域を除いた微結晶セルロース等に分類される。 Cellulose-based polymers can be obtained using cellulose as a raw material. That is, cellulose that can be used as a cellulose raw material in the present invention is a polysaccharide with a structure in which D-glucopyranose (simply referred to as "glucose residue" or "anhydroglucose") is linked by β, 1-4 bonds. means. Cellulose is generally classified into natural cellulose, regenerated cellulose, fine cellulose, microcrystalline cellulose excluding non-crystalline regions, etc. based on its origin, manufacturing method, etc.
　天然セルロースとしては、晒パルプまたは未晒パルプ（晒木材パルプまたは未晒木材パルプ）；リンター、精製リンター；酢酸菌等の微生物によって生産されるセルロース、等が例示される。晒パルプ又は未晒パルプの原料は特に限定されず、例えば、木材、木綿、わら、竹等が挙げられる。また、晒パルプ又は未晒パルプの製造方法も特に限定されず、機械的方法、化学的方法、あるいはその中間で二つを組み合わせた方法でもよい。製造方法により分類される晒パルプまたは未晒パルプとしては例えば、メカニカルパルプ、ケミカルパルプ、砕木パルプ、亜硫酸パルプ、クラフトパルプ等が挙げられる。さらに、製紙用パルプの他に溶解パルプを用いてもよい。溶解パルプとは、化学的に精製されたパルプであり、主として薬品に溶解して使用され、人造繊維、セロハンなどの主原料となる。 Examples of natural cellulose include bleached pulp or unbleached pulp (bleached wood pulp or unbleached wood pulp); linters, purified linters; cellulose produced by microorganisms such as acetic acid bacteria, and the like. The raw material for bleached pulp or unbleached pulp is not particularly limited, and examples thereof include wood, cotton, straw, bamboo, and the like. Furthermore, the method for producing bleached pulp or unbleached pulp is not particularly limited, and may be a mechanical method, a chemical method, or a combination of the two in between. Examples of bleached pulp or unbleached pulp classified by manufacturing method include mechanical pulp, chemical pulp, groundwood pulp, sulfite pulp, and kraft pulp. Furthermore, dissolving pulp may be used in addition to papermaking pulp. Dissolving pulp is a chemically refined pulp that is mainly used after being dissolved in chemicals, and is the main raw material for artificial fibers, cellophane, etc.
　再生セルロースとしては、セルロースを銅アンモニア溶液、セルロースザンテート溶液、モルフォリン誘導体など何らかの溶媒に溶解し、改めて紡糸されたものが例示される。 Examples of regenerated cellulose include those obtained by dissolving cellulose in some kind of solvent such as a cupric ammonia solution, a cellulose xanthate solution, or a morpholine derivative, and respinning the resulting cellulose.
　微細セルロースとしては、上記天然セルロースや再生セルロースをはじめとする、セルロース系素材を、解重合処理（例えば、酸加水分解、アルカリ加水分解、酵素分解、爆砕処理、振動ボールミル処理等）して得られるものや、前記セルロース系素材を、機械的に処理して得られるものが例示される。 Fine cellulose is obtained by depolymerizing cellulose materials such as the above-mentioned natural cellulose and regenerated cellulose (for example, acid hydrolysis, alkaline hydrolysis, enzymatic decomposition, blasting treatment, vibrating ball mill treatment, etc.) Examples include those obtained by mechanically processing the above-mentioned cellulose-based materials.
　＜化学変性されたセルロース系ポリマー＞　
　化学変性されたセルロース系ポリマーとしては、例えば、アニオン変性して得られるセルロース系ポリマーを用いてもよいし、カチオン変性して得られるセルロース系ポリマーを用いてもよい。 <Chemically modified cellulose polymer>
As the chemically modified cellulose polymer, for example, a cellulose polymer obtained by anion modification or a cellulose polymer obtained by cation modification may be used.
　アニオン変性して得られるセルロース系ポリマーとしては、カルボキシ化セルロース（酸化セルロースとも呼ぶ）、カルボキシメチルセルロース、ヒドロキシメチルセルロース、ヒドロキシエチルセルロース、ヒドロキシプロピルセルロース、リン酸エステル化セルロース等が例示され、これらのセルロース系ポリマーは、塩の形態であってもよい。塩型の種類は問わないが、ナトリウム塩等の金属塩やアンモニウム塩など、用途や目的に応じて、良好な塩を選択することが好ましい。本発明において用いるセルロース系ポリマーに特に制限はないが、カルボキシメチルセルロースおよび／又はその塩を用いることが好ましい。 Examples of cellulose-based polymers obtained by anionic modification include carboxylated cellulose (also called oxidized cellulose), carboxymethyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, and phosphate-esterified cellulose. may be in the form of a salt. Although the type of salt does not matter, it is preferable to select a suitable salt, such as a metal salt such as a sodium salt or an ammonium salt, depending on the use and purpose. Although there are no particular limitations on the cellulose-based polymer used in the present invention, it is preferable to use carboxymethylcellulose and/or a salt thereof.
　（カルボキシ化セルロース（酸化セルロース））
　アニオン変性して得られるセルロース系ポリマーとして、カルボキシ化セルロース（酸化セルロース）を用いる場合には、セルロース原料を公知の方法でカルボキシ化（酸化）することにより得ることができる。カルボキシ化の際には、セルロース系ポリマーの絶乾質量に対して、カルボキシ基の量が２．４～９．３ｍｍｏｌ／ｇ、好ましくは３．１～８．０ｍｍｏｌ／ｇ、更に好ましくは３．７～６．８ｍｍｏｌ／ｇとなるように調整することが好ましい。 (Carboxylated cellulose (oxidized cellulose))
When carboxylated cellulose (oxidized cellulose) is used as the cellulose-based polymer obtained by anion modification, it can be obtained by carboxylating (oxidizing) a cellulose raw material by a known method. During carboxylation, the amount of carboxyl groups is 2.4 to 9.3 mmol/g, preferably 3.1 to 8.0 mmol/g, more preferably 3. It is preferable to adjust it to 7 to 6.8 mmol/g.
　ここで、カルボキシ基量は例えば、以下のように測定することができる。すなわち、酸化セルロースの０．５質量％スラリー（水分散液）６０ｍＬを調製し、０．１Ｍ塩酸水溶液を加えてｐＨ２．５とした後、０．０５Ｎの水酸化ナトリウム水溶液を滴下してｐＨが１１になるまで電気伝導度を測定する。電気伝導度の変化が緩やかな弱酸の中和段階において消費された水酸化ナトリウム量（ａ）から、下式を用いて算出することができる。
　カルボキシ基量〔ｍｍｏｌ／ｇ酸化セルロース〕＝ａ〔ｍＬ〕×０．０５／酸化セルロース質量〔ｇ〕 Here, the amount of carboxy groups can be measured, for example, as follows. That is, 60 mL of 0.5% by mass slurry (aqueous dispersion) of oxidized cellulose was prepared, and after adding 0.1M hydrochloric acid aqueous solution to adjust the pH to 2.5, 0.05N sodium hydroxide aqueous solution was added dropwise to adjust the pH. Measure the electrical conductivity until it reaches 11. It can be calculated using the following formula from the amount (a) of sodium hydroxide consumed in the neutralization stage of the weak acid where the change in electrical conductivity is gradual.
Carboxy group amount [mmol/g oxidized cellulose] = a [mL] x 0.05/mass of oxidized cellulose [g]
　カルボキシ化（酸化）方法の一例として、セルロース原料を、Ｎ－オキシル化合物と、臭化物、ヨウ化物もしくはこれらの混合物からなる群から選択される化合物との存在下で酸化剤を用いて水中で酸化する方法を挙げることができる。この酸化反応により、セルロース表面のグルコピラノース環のＣ６位の一級水酸基が選択的に酸化され、表面にアルデヒド基と、カルボキシ基（－ＣＯＯＨ）またはカルボキシレート基（－ＣＯＯ－）とを有するセルロース繊維を得ることができる。反応時のセルロースの濃度は特に限定されないが、５質量％以下が好ましい。 As an example of a carboxylation (oxidation) method, a cellulosic raw material is oxidized in water with an oxidizing agent in the presence of an N-oxyl compound and a compound selected from the group consisting of bromides, iodides or mixtures thereof. Here are some methods. Through this oxidation reaction, the primary hydroxyl group at the C6 position of the glucopyranose ring on the cellulose surface is selectively oxidized, resulting in cellulose fibers having an aldehyde group and a carboxy group (-COOH) or carboxylate group (-COO-) on the surface. can be obtained. The concentration of cellulose during the reaction is not particularly limited, but is preferably 5% by mass or less.
　Ｎ－オキシル化合物とは、ニトロキシラジカルを発生しうる化合物をいう。Ｎ－オキシル化合物としては、目的の酸化反応を促進する化合物であれば、いずれの化合物も使用できる。例えば、２，２，６，６－テトラメチルピペリジン－１－オキシラジカル（ＴＥＭＰＯ）およびその誘導体（例えば４－ヒドロキシＴＥＭＰＯ）が挙げられる。 The N-oxyl compound refers to a compound that can generate nitroxy radicals. As the N-oxyl compound, any compound can be used as long as it promotes the desired oxidation reaction. Examples include 2,2,6,6-tetramethylpiperidine-1-oxyradical (TEMPO) and its derivatives (eg, 4-hydroxyTEMPO).
　Ｎ－オキシル化合物の使用量は、原料となるセルロースを酸化できる触媒量であればよく、特に制限されない。例えば、絶乾１ｇのセルロースに対して、０．０１～１０ｍｍｏｌが好ましく、０．０１～１ｍｍｏｌがより好ましく、０．０５～０．５ｍｍｏｌがさらに好ましい。また、反応系に対し０．１～４ｍｍｏｌ／Ｌ程度が好ましい。 The amount of the N-oxyl compound used is not particularly limited as long as it is a catalytic amount that can oxidize cellulose as a raw material. For example, it is preferably 0.01 to 10 mmol, more preferably 0.01 to 1 mmol, and even more preferably 0.05 to 0.5 mmol, per 1 g of bone dry cellulose. Further, it is preferably about 0.1 to 4 mmol/L to the reaction system.
　臭化物とは臭素を含む化合物であり、その例には、水中で解離してイオン化可能な臭化アルカリ金属が含まれる。また、ヨウ化物とはヨウ素を含む化合物であり、その例には、ヨウ化アルカリ金属が含まれる。臭化物またはヨウ化物の使用量は、酸化反応を促進できる範囲で選択できる。臭化物およびヨウ化物の合計量は、例えば、絶乾１ｇのセルロースに対して、０．１～１００ｍｍｏｌが好ましく、０．１～１０ｍｍｏｌがより好ましく、０．５～５ｍｍｏｌがさらに好ましい。 A bromide is a compound containing bromine, and examples thereof include alkali metal bromides that can be dissociated and ionized in water. Moreover, iodide is a compound containing iodine, and examples thereof include alkali metal iodide. The amount of bromide or iodide to be used can be selected within a range that can promote the oxidation reaction. The total amount of bromide and iodide is, for example, preferably 0.1 to 100 mmol, more preferably 0.1 to 10 mmol, and even more preferably 0.5 to 5 mmol, per 1 g of bone dry cellulose.
　酸化剤としては、公知のものを使用でき、例えば、ハロゲン、次亜ハロゲン酸、亜ハロゲン酸、過ハロゲン酸またはそれらの塩、ハロゲン酸化物、過酸化物などを使用できる。中でも、安価で環境負荷の少ない次亜塩素酸ナトリウムが好ましい。酸化剤の使用量としては、例えば、絶乾１ｇのセルロースに対して、０．５～５００ｍｍｏｌが好ましく、０．５～５０ｍｍｏｌがより好ましく、１～２５ｍｍｏｌがさらに好ましく、３～１０ｍｍｏｌが最も好ましい。また、例えば、Ｎ－オキシル化合物１ｍｏｌに対して１～４０ｍｏｌが好ましい。 As the oxidizing agent, known ones can be used, such as halogen, hypohalous acid, halous acid, perhalogenic acid, or salts thereof, halogen oxides, peroxides, etc. Among these, sodium hypochlorite is preferred because it is inexpensive and has a low environmental impact. The amount of the oxidizing agent used is, for example, preferably 0.5 to 500 mmol, more preferably 0.5 to 50 mmol, even more preferably 1 to 25 mmol, and most preferably 3 to 10 mmol, per 1 g of bone dry cellulose. Further, for example, it is preferably 1 to 40 mol per 1 mol of the N-oxyl compound.
　セルロースの酸化は、比較的温和な条件であっても反応を効率よく進行させられる。よって、反応温度は４～４０℃が好ましく、また１５～３０℃程度の室温であってもよい。反応の進行に伴ってセルロース中にカルボキシ基が生成するため、反応液のｐＨの低下が認められる。酸化反応を効率よく進行させるためには、水酸化ナトリウム水溶液などのアルカリ性溶液を添加して、反応液のｐＨを８～１２、好ましくは１０～１１程度に維持することが好ましい。反応媒体は、取扱容易性や、副反応が生じにくいこと等から、水が好ましい。 The oxidation of cellulose can proceed efficiently even under relatively mild conditions. Therefore, the reaction temperature is preferably 4 to 40°C, and may be room temperature of about 15 to 30°C. As the reaction progresses, carboxy groups are generated in the cellulose, so a decrease in the pH of the reaction solution is observed. In order for the oxidation reaction to proceed efficiently, it is preferable to add an alkaline solution such as an aqueous sodium hydroxide solution to maintain the pH of the reaction solution at about 8 to 12, preferably about 10 to 11. Water is preferable as the reaction medium because of its ease of handling and the fact that side reactions are less likely to occur.
　酸化反応における反応時間は、酸化の進行の程度に従って適宜設定することができ、通常は０．５～６時間、例えば、０．５～４時間程度である。 The reaction time in the oxidation reaction can be appropriately set according to the degree of progress of oxidation, and is usually about 0.5 to 6 hours, for example about 0.5 to 4 hours.
　また、酸化反応は、２段階に分けて実施してもよい。例えば、１段目の反応終了後に濾別して得られた酸化セルロースを、再度、同一または異なる反応条件で酸化させることにより、１段目の反応で副生する食塩による反応阻害を受けることなく、効率よく酸化させることができる。カルボキシ化（酸化）方法の別の例として、オゾンを含む気体とセルロース原料とを接触させることにより酸化する方法を挙げることができる。この酸化反応により、グルコピラノース環の少なくとも２位および６位の水酸基が酸化されると共に、セルロース鎖の分解が起こる。オゾンを含む気体中のオゾン濃度は、５０～２５０ｇ／ｍ３であることが好ましく、５０～２２０ｇ／ｍ３であることがより好ましい。セルロース原料に対するオゾン添加量は、セルロース原料の固形分を１００質量部とした際に、０．１～３０質量部であることが好ましく、５～３０質量部であることがより好ましい。オゾン処理温度は、０～５０℃であることが好ましく、２０～５０℃であることがより好ましい。オゾン処理時間は、特に限定されないが、１～３６０分程度であり、３０～３６０分程度が好ましい。オゾン処理の条件がこれらの範囲内であると、セルロースが過度に酸化および分解されることを防ぐことができ、酸化セルロースの収率が良好となる。オゾン処理を施した後に、酸化剤を用いて、追酸化処理を行ってもよい。追酸化処理に用いる酸化剤は、特に限定されないが、二酸化塩素、亜塩素酸ナトリウム等の塩素系化合物や、酸素、過酸化水素、過硫酸、過酢酸などが挙げられる。例えば、これらの酸化剤を水またはアルコール等の極性有機溶媒中に溶解して酸化剤溶液を作成し、溶液中にセルロース原料を浸漬させることにより追酸化処理を行うことができる。 Further, the oxidation reaction may be carried out in two stages. For example, by oxidizing the oxidized cellulose obtained by filtration after the completion of the first-stage reaction again under the same or different reaction conditions, the efficiency can be improved without being inhibited by the salt produced as a by-product in the first-stage reaction. Can be oxidized well. Another example of the carboxylation (oxidation) method is a method of oxidizing a cellulose raw material by bringing it into contact with a gas containing ozone. This oxidation reaction oxidizes the hydroxyl groups at at least the 2- and 6-positions of the glucopyranose ring and causes decomposition of the cellulose chain. The ozone concentration in the ozone-containing gas is preferably 50 to 250 g/m 3 , more preferably 50 to 220 g/m 3 . The amount of ozone added to the cellulose raw material is preferably 0.1 to 30 parts by mass, more preferably 5 to 30 parts by mass, when the solid content of the cellulose raw material is 100 parts by mass. The ozone treatment temperature is preferably 0 to 50°C, more preferably 20 to 50°C. The ozone treatment time is not particularly limited, but is about 1 to 360 minutes, preferably about 30 to 360 minutes. When the ozone treatment conditions are within these ranges, excessive oxidation and decomposition of cellulose can be prevented, resulting in a good yield of oxidized cellulose. After the ozone treatment, additional oxidation treatment may be performed using an oxidizing agent. The oxidizing agent used in the additional oxidation treatment is not particularly limited, but examples thereof include chlorine-based compounds such as chlorine dioxide and sodium chlorite, oxygen, hydrogen peroxide, persulfuric acid, and peracetic acid. For example, the additional oxidation treatment can be performed by dissolving these oxidizing agents in water or a polar organic solvent such as alcohol to prepare an oxidizing agent solution, and immersing the cellulose raw material in the solution.
　酸化セルロースのカルボキシ基の量は、上記した酸化剤の添加量、反応時間等の反応条件をコントロールすることにより調整することができる。 The amount of carboxy groups in the oxidized cellulose can be adjusted by controlling the reaction conditions such as the amount of the oxidizing agent added and the reaction time.
　（エーテル化）
　アニオン変性して得られるセルロース系ポリマーとして上記にて例示したカルボキシメチルセルロース、ヒドロキシメチルセルロース、ヒドロキシエチルセルロースまたはヒドロキシプロピルセルロースは、セルロース原料を公知の方法でエーテル化することにより得てもよいし、市販品を用いてもよい。 (etherification)
Carboxymethyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose, or hydroxypropyl cellulose, which are exemplified above as cellulose-based polymers obtained by anion modification, may be obtained by etherifying cellulose raw materials by a known method, or commercially available products. May be used.
　（カルボキシメチルセルロース又はその塩）
　例えば、カルボキシメチルセルロース又はその塩（以下、「ＣＭＣ」ということがある。）を得る場合において、カルボキシメチルセルロース又はその塩の製法は限定されず、公知のカルボキシメチルセルロース又はその塩の製法を適用することができる。即ち、原料であるセルロースをマーセル化剤（アルカリ）で処理してマーセル化セルロース（アルカリセルロース）を調製した後に、エーテル化剤を添加してエーテル化反応させることで本発明におけるカルボキシメチルセルロース又はその塩を製造することができる。 (Carboxymethyl cellulose or its salt)
For example, when obtaining carboxymethylcellulose or a salt thereof (hereinafter sometimes referred to as "CMC"), the method for producing carboxymethylcellulose or a salt thereof is not limited, and any known method for producing carboxymethylcellulose or a salt thereof may be applied. can. That is, after treating cellulose, which is a raw material, with a mercerizing agent (alkali) to prepare mercerized cellulose (alkali cellulose), an etherifying agent is added to cause an etherification reaction to produce carboxymethylcellulose or its salt in the present invention. can be manufactured.
　原料のセルロースとしては、上述のセルロースであれば特に制限なく用いることができるが、セルロース純度が高いものが好ましく、特に、溶解パルプ、リンターを用いることが好ましい。これらを用いることにより、純度の高いカルボキシメチルセルロース又はその塩を得ることができる。 As the raw material cellulose, any of the above-mentioned celluloses can be used without particular limitation, but those with high cellulose purity are preferred, and it is particularly preferred to use dissolving pulp and linters. By using these, highly pure carboxymethyl cellulose or a salt thereof can be obtained.
　マーセル化剤としては水酸化ナトリウム、水酸化カリウム等の水酸化アルカリ金属塩等を使用することができる。エーテル化剤としてはモノクロロ酢酸、モノクロロ酢酸ソーダ等を使用することができる。 As the mercerization agent, alkali metal hydroxide salts such as sodium hydroxide and potassium hydroxide can be used. As the etherification agent, monochloroacetic acid, monochloroacetic acid soda, etc. can be used.
　水溶性の一般的なカルボキシメチルセルロースの製法の場合のマーセル化剤とエーテル化剤のモル比は、エーテル化剤としてモノクロロ酢酸を使用する場合では２．００～２．４５が一般的に採用される。その理由は、２．００未満であるとエーテル化反応が十分に行われない可能性があるため、未反応のモノクロロ酢酸が残って無駄が生じる可能性があること、及び２．４５を超えると過剰のマーセル化剤とモノクロロ酢酸による副反応が進行してグリコール酸アルカリ金属塩が生成するおそれがあるため、不経済となる可能性があることにある。 The molar ratio of the mercerizing agent to the etherifying agent in the general production method of water-soluble carboxymethylcellulose is generally 2.00 to 2.45 when monochloroacetic acid is used as the etherifying agent. . The reason for this is that if it is less than 2.00, the etherification reaction may not be carried out sufficiently, resulting in unreacted monochloroacetic acid remaining and being wasted; This is because there is a possibility that a side reaction between an excess of the mercerizing agent and monochloroacetic acid may proceed to produce an alkali metal salt of glycolic acid, which may be uneconomical.
　本発明において、カルボキシメチルセルロース又はその塩は、市販のものをそのまま、或いは必要に応じて処理してから用いてもよい。市販品としては、例えば、日本製紙（株）製の商品名「サンローズ」（カルボキシメチルセルロースのナトリウム塩）が挙げられる。 In the present invention, commercially available carboxymethylcellulose or its salt may be used as it is, or after treatment if necessary. Commercially available products include, for example, the trade name "Sunrose" (sodium salt of carboxymethyl cellulose) manufactured by Nippon Paper Industries, Ltd.
　本発明のカルボキシメチルセルロース又はその塩は、その無水グルコース単位当りのカルボキシメチル置換度が、０．５以上であることが重要であり、０．６以上であることがより好ましい。カルボキシメチル置換度が０．５未満であると、水への溶解が十分でなくなるおそれがある。 It is important that the carboxymethylcellulose or salt thereof of the present invention has a degree of carboxymethyl substitution per anhydroglucose unit of 0.5 or more, more preferably 0.6 or more. If the degree of carboxymethyl substitution is less than 0.5, the solubility in water may be insufficient.
　本発明において無水グルコース単位とは、セルロースを構成する個々の無水グルコース（グルコース残基）を意味する。また、カルボキシメチル置換度（エーテル化度ともいう）とは、セルロースを構成するグルコース残基中の水酸基（－ＯＨ）のうちカルボキシメチルエーテル基（－ＯＣＨ２ＣＯＯＨ）に置換されているものの割合を示す。なお、カルボキシメチル置換度はＤＳまたはＣＭ－ＤＳと略すことがある。 In the present invention, anhydroglucose units refer to individual anhydroglucoses (glucose residues) that constitute cellulose. Furthermore, the degree of carboxymethyl substitution (also referred to as the degree of etherification) refers to the proportion of hydroxyl groups (-OH) in glucose residues constituting cellulose that are substituted with carboxymethyl ether groups (-OCH 2 COOH). show. Note that the degree of carboxymethyl substitution may be abbreviated as DS or CM-DS.
　カルボキシメチルセルロース又はその塩の無水グルコース単位当りのカルボキシメチル置換度の上限は、１．２以下であることが好ましく、１．０以下であることがより好ましい。 The upper limit of the degree of carboxymethyl substitution per anhydroglucose unit of carboxymethyl cellulose or its salt is preferably 1.2 or less, more preferably 1.0 or less.
　なお、カルボキシメチル基の置換度の測定方法は以下の通りである：
　試料約２．０ｇを精秤して、３００ｍＬ共栓付き三角フラスコに入れる。メタノール１０００ｍＬに特級濃硝酸１００ｍＬを加えた液１００ｍＬを加え、３時間振盪して、カルボキシメチルセルロースの塩（ＣＭＣ）をＨ－ＣＭＣ（水素型カルボキシメチルセルロース）に変換する。その絶乾Ｈ－ＣＭＣを１．５～２．０ｇ精秤し、３００ｍＬ共栓付き三角フラスコに入れる。８０％メタノール１５ｍＬでＨ－ＣＭＣを湿潤し、０．１Ｎ－ＮａＯＨを１００ｍＬ加え、室温で３時間振盪する。指示薬として、フェノールフタレインを用いて、０．１Ｎ－Ｈ２ＳＯ４で過剰のＮａＯＨを逆滴定し、次式によってカルボキシメチル置換度（ＤＳ値）を算出する。
Ａ＝［（１００×Ｆ’－０．１Ｎ－Ｈ２ＳＯ４（ｍＬ）×Ｆ）×０．１］／（Ｈ－ＣＭＣの絶乾質量（ｇ））
カルボキシメチル置換度＝０．１６２×Ａ／（１－０．０５８×Ａ）
Ｆ’：０．１Ｎ－Ｈ２ＳＯ４のファクター
Ｆ：０．１Ｎ－ＮａＯＨのファクター The method for measuring the degree of substitution of carboxymethyl groups is as follows:
Weigh approximately 2.0 g of the sample accurately and place it in a 300 mL Erlenmeyer flask with a stopper. Add 100 mL of a solution prepared by adding 100 mL of special grade concentrated nitric acid to 1000 mL of methanol, and shake for 3 hours to convert carboxymethyl cellulose salt (CMC) to H-CMC (hydrogen form carboxymethyl cellulose). Accurately weigh 1.5 to 2.0 g of the bone-dried H-CMC and place it in a 300 mL Erlenmeyer flask with a stopper. Wet H-CMC with 15 mL of 80% methanol, add 100 mL of 0.1N NaOH, and shake at room temperature for 3 hours. Excess NaOH is back titrated with 0.1N--H 2 SO 4 using phenolphthalein as an indicator, and the degree of carboxymethyl substitution (DS value) is calculated by the following formula.
A=[(100×F'-0.1N-H 2 SO 4 (mL)×F)×0.1]/(bone-dry mass of H-CMC (g))
Carboxymethyl substitution degree = 0.162 x A/(1-0.058 x A)
F': Factor of 0.1N-H 2 SO 4 F: Factor of 0.1N-NaOH
　本発明に用いるＣＭＣは、１種類であってもよいし、エーテル化度、ＣＭ－ＤＳ、粘度、分子量などの異なる２種類以上のＣＭＣの組み合わせであってもよい。なお、粘度については後述する。 The CMC used in the present invention may be one type, or a combination of two or more types of CMC with different degrees of etherification, CM-DS, viscosity, molecular weight, etc. Viscosity will be described later.
　（リン酸エステル化セルロース）
　アニオン変性して得られるセルロース系ポリマーとして、リン酸エステル化セルロースを用いる場合、当該セルロースは、前述のセルロース原料にリン酸系化合物Ａの粉末や水溶液を混合する方法、セルロース原料のスラリーにリン酸系化合物Ａの水溶液を添加する方法により得られる。 (phosphate esterified cellulose)
When using phosphoric acid esterified cellulose as a cellulose-based polymer obtained by anion modification, the cellulose can be prepared by mixing the powder or aqueous solution of phosphoric acid compound A with the cellulose raw material described above, or by adding phosphoric acid to a slurry of the cellulose raw material. It can be obtained by adding an aqueous solution of Compound A.
　リン酸系化合物Ａとしては、リン酸、ポリリン酸、亜リン酸、ホスホン酸、ポリホスホン酸あるいはこれらのエステルが挙げられる。これらは塩の形態であってもよい。これらの中でも、低コストであり、扱いやすいなどの理由からリン酸基を有する化合物が好ましい。リン酸基を有する化合物としては、リン酸、リン酸二水素ナトリウム、リン酸水素二ナトリウム、リン酸三ナトリウム、ピロリン酸ナトリウム、メタリン酸ナトリウム、リン酸二水素カリウム、リン酸水素二カリウム、リン酸三カリウム、ピロリン酸カリウム、メタリン酸カリウム、リン酸二水素アンモニウム、リン酸水素二アンモニウム、リン酸三アンモニウム、ピロリン酸アンモニウム、メタリン酸アンモニウム等が挙げられる。これらは１種、あるいは２種以上を併用できる。これらのうち、リン酸基導入の効率が高く、工業的に適用しやすい観点から、リン酸、リン酸のナトリウム塩、リン酸のカリウム塩、リン酸のアンモニウム塩がより好ましい。特にリン酸二水素ナトリウム、リン酸水素二ナトリウムが好ましい。また、反応の均一性が高まり、かつリン酸基導入の効率が高くなることから前記リン酸系化合物Ａは水溶液として用いることが好ましい。リン酸系化合物Ａの水溶液のｐＨは、リン酸基導入の効率が高くなることから７以下であることが好ましいが、パルプ繊維の加水分解を抑える観点からｐＨ３～７が好ましい。 Examples of the phosphoric acid compound A include phosphoric acid, polyphosphoric acid, phosphorous acid, phosphonic acid, polyphosphonic acid, or esters thereof. These may be in the form of salts. Among these, compounds having a phosphoric acid group are preferred because they are low cost and easy to handle. Examples of compounds having a phosphoric acid group include phosphoric acid, sodium dihydrogen phosphate, disodium hydrogen phosphate, trisodium phosphate, sodium pyrophosphate, sodium metaphosphate, potassium dihydrogen phosphate, dipotassium hydrogen phosphate, and phosphoric acid. Examples include tripotassium acid, potassium pyrophosphate, potassium metaphosphate, ammonium dihydrogen phosphate, diammonium hydrogen phosphate, triammonium phosphate, ammonium pyrophosphate, and ammonium metaphosphate. These can be used alone or in combination of two or more. Among these, phosphoric acid, a sodium salt of phosphoric acid, a potassium salt of phosphoric acid, and an ammonium salt of phosphoric acid are more preferable from the viewpoint of high efficiency of introducing a phosphoric acid group and easy industrial application. Particularly preferred are sodium dihydrogen phosphate and disodium hydrogen phosphate. Further, it is preferable to use the phosphoric acid compound A in the form of an aqueous solution, since the uniformity of the reaction and the efficiency of introducing phosphoric acid groups are increased. The pH of the aqueous solution of the phosphoric acid compound A is preferably 7 or less since this increases the efficiency of introducing phosphoric acid groups, but the pH is preferably 3 to 7 from the viewpoint of suppressing hydrolysis of pulp fibers.
　リン酸エステル化セルロースの製造方法の一例として以下の方法を挙げることができる。固形分濃度０．１～１０質量％のセルロース原料の分散液に、リン酸系化合物Ａを撹拌しながら添加してセルロースにリン酸基を導入する。セルロース原料を１００質量部とした際に、リン酸系化合物Ａの添加量はリン元素量として、０．２～５００質量部であることが好ましく、１～４００質量部であることがより好ましい。リン酸系化合物Ａの割合が前記下限値以上であれば、微細繊維状セルロースの収率をより向上させることができる。しかし、前記上限値を超えると収率向上の効果は頭打ちとなるのでコスト面から好ましくない。 The following method can be mentioned as an example of the method for producing phosphoric acid esterified cellulose. A phosphoric acid compound A is added to a dispersion of a cellulose raw material having a solid content concentration of 0.1 to 10% by mass while stirring to introduce phosphoric acid groups into the cellulose. When the cellulose raw material is 100 parts by mass, the amount of phosphoric acid compound A added is preferably 0.2 to 500 parts by mass, more preferably 1 to 400 parts by mass as the amount of phosphorus element. If the proportion of phosphoric acid compound A is equal to or higher than the lower limit, the yield of fine fibrous cellulose can be further improved. However, if the above upper limit is exceeded, the effect of improving the yield reaches a ceiling, which is not preferable from a cost standpoint.
　この際、セルロース原料、リン酸系化合物Ａの他に、これ以外の化合物Ｂの粉末や水溶液を混合してもよい。化合物Ｂは特に限定されないが、塩基性を示す窒素含有化合物が好ましい。ここでの「塩基性」は、フェノールフタレイン指示薬の存在下で水溶液が桃～赤色を呈すること、または水溶液のｐＨが７より大きいことと定義される。本発明で用いる塩基性を示す窒素含有化合物は、本発明の効果を奏する限り特に限定されないが、アミノ基を有する化合物が好ましい。例えば、尿素、メチルアミン、エチルアミン、トリメチルアミン、トリエチルアミン、モノエタノールアミン、ジエタノールアミン、トリエタノールアミン、ピリジン、エチレンジアミン、ヘキサメチレンジアミンなどが挙げられるが、特に限定されない。この中でも低コストで扱いやすい尿素が好ましい。化合物Ｂの添加量はセルロース原料の固形分１００質量部に対して、２～１０００質量部が好ましく、１００～７００質量部がより好ましい。反応温度は０～９５℃が好ましく、３０～９０℃がより好ましい。反応時間は特に限定されないが、１～６００分程度であり、３０～４８０分がより好ましい。エステル化反応の条件がこれらの範囲内であると、セルロースが過度にエステル化されて溶解しやすくなることを防ぐことができ、リン酸エステル化セルロースの収率が良好となる。得られたリン酸エステル化セルロース懸濁液を脱水した後、セルロースの加水分解を抑える観点から、１００～１７０℃で加熱処理することが好ましい。さらに、加熱処理の際に水が含まれている間は１３０℃以下、好ましくは１１０℃以下で加熱し、水を除いた後、１００～１７０℃で加熱処理することが好ましい。
　リン酸エステル化セルロースのグルコース単位当たりのリン酸基置換度は０．００１～０．４０であることが好ましい。 At this time, in addition to the cellulose raw material and phosphoric acid compound A, powder or aqueous solution of compound B may be mixed. Compound B is not particularly limited, but is preferably a nitrogen-containing compound that exhibits basicity. "Basic" herein is defined as the aqueous solution exhibiting a pink to red color in the presence of the phenolphthalein indicator, or the pH of the aqueous solution being greater than 7. The basic nitrogen-containing compound used in the present invention is not particularly limited as long as it exhibits the effects of the present invention, but compounds having an amino group are preferred. Examples include, but are not limited to, urea, methylamine, ethylamine, trimethylamine, triethylamine, monoethanolamine, diethanolamine, triethanolamine, pyridine, ethylenediamine, and hexamethylenediamine. Among these, urea is preferred because it is low cost and easy to handle. The amount of compound B added is preferably 2 to 1000 parts by weight, more preferably 100 to 700 parts by weight, based on 100 parts by weight of the solid content of the cellulose raw material. The reaction temperature is preferably 0 to 95°C, more preferably 30 to 90°C. The reaction time is not particularly limited, but is approximately 1 to 600 minutes, more preferably 30 to 480 minutes. When the conditions for the esterification reaction are within these ranges, cellulose can be prevented from being excessively esterified and easily dissolved, and the yield of phosphoric acid esterified cellulose can be improved. After dehydrating the obtained phosphoric acid esterified cellulose suspension, it is preferably heat-treated at 100 to 170° C. from the viewpoint of suppressing hydrolysis of cellulose. Further, during heat treatment, it is preferable to heat at 130° C. or lower, preferably 110° C. or lower while water is contained, and after removing water, heat treatment at 100 to 170° C.
The degree of phosphoric acid group substitution per glucose unit of the phosphoric acid esterified cellulose is preferably 0.001 to 0.40.
　（カチオン化）
　化学変性されたセルロース系ポリマーとして、カチオン変性されたセルロース系ポリマーを用いる場合には、前記カルボキシ化セルロースをさらにカチオン化したセルロースを使用することができる。当該カチオン変性されたセルロースは、前記カルボキシ化セルロース原料に、グリシジルトリメチルアンモニウムクロリド、３－クロロ－２－ヒドロキシプロピルトリアルキルアンモニウムハライドまたはそのハロヒドリン型などのカチオン化剤と、触媒である水酸化アルカリ金属（水酸化ナトリウム、水酸化カリウムなど）を、水または炭素数１～４のアルコールの存在下で反応させることによって得ることができる。 (cationization)
When using a cationically modified cellulose polymer as the chemically modified cellulose polymer, cellulose obtained by further cationizing the carboxylated cellulose can be used. The cationically modified cellulose is produced by adding a cationizing agent such as glycidyltrimethylammonium chloride, 3-chloro-2-hydroxypropyltrialkylammonium halide or its halohydrin type to the carboxylated cellulose raw material, and an alkali metal hydroxide as a catalyst. (sodium hydroxide, potassium hydroxide, etc.) in the presence of water or an alcohol having 1 to 4 carbon atoms.
　グルコース単位当たりのカチオン置換度は０．０２～０．５０であることが好ましい。当該カチオン置換度は、反応させるカチオン化剤の添加量、水または炭素数１～４のアルコールの組成比率によって調整できる。 The degree of cation substitution per glucose unit is preferably 0.02 to 0.50. The degree of cation substitution can be adjusted by adjusting the amount of the cationizing agent to be reacted and the composition ratio of water or alcohol having 1 to 4 carbon atoms.
　（粘度）
　本発明において、粉砕対象の化学変性されたセルロース系ポリマーの２５℃においてＢ型粘度計（３０ｒｐｍ）により測定された１質量％水溶液の粘度は、好ましくは１,０００～２０，０００ｍＰａ・ｓ、より好ましくは１，５００～１５，０００ｍＰａ・ｓ、さらに好ましくは１，５００～１０，０００ｍＰａ・ｓである。 (viscosity)
In the present invention, the viscosity of a 1% by mass aqueous solution of the chemically modified cellulose polymer to be pulverized at 25°C as measured by a B-type viscometer (30 rpm) is preferably 1,000 to 20,000 mPa·s, or more. It is preferably 1,500 to 15,000 mPa·s, more preferably 1,500 to 10,000 mPa·s.
　なお、粘度の測定方法は以下の通りである：
　粉砕対象の化学変性されたセルロース系ポリマーを、１０００ｍＬ容ガラスビーカーに測りとり、蒸留水９００ｍＬに分散し、固形分１％（ｗ／ｖ）となるように水分散体を調製する。水分散体を２５℃で撹拌機を用いて６００ｒｐｍで３時間撹拌する。その後、ＪＩＳ－Ｚ－８８０３の方法に準じて、Ｂ型粘度計（東機産業社製）を用いて、Ｎｏ．４ローター／回転数３０ｒｐｍで３分後の粘度を測定する。 The viscosity measurement method is as follows:
A chemically modified cellulose polymer to be crushed is measured into a 1000 mL glass beaker and dispersed in 900 mL of distilled water to prepare an aqueous dispersion with a solid content of 1% (w/v). The aqueous dispersion is stirred at 25° C. using a stirrer at 600 rpm for 3 hours. Thereafter, according to the method of JIS-Z-8803, using a B-type viscometer (manufactured by Toki Sangyo Co., Ltd.), No. Measure the viscosity after 3 minutes with 4 rotors/30 rpm.
　＜未変性パルプ＞
　未変性パルプとしては、特に限定されないが、未変性パルプを用いた粉末状セルロースを用いることが好ましい。未変性パルプを用いた粉末状セルロースとしては、パルプを機械粉砕、もしくは酸加水分解して粉末化したもの等が挙げられる。 <Undenatured pulp>
The unmodified pulp is not particularly limited, but it is preferable to use powdered cellulose using unmodified pulp. Examples of powdered cellulose using unmodified pulp include those obtained by mechanically crushing pulp or acid hydrolyzing it to powder.
　粉末状セルロースの製造方法は、セルロース原料から粉末状セルロースを得る方法であれば特に限定されないが、例えば、少なくとも粉砕処理を含む方法が挙げられ、不純物が少ない粉末状セルロースが得られやすい点で、酸加水分解処理をさらに行う方法が好ましい。 The method for producing powdered cellulose is not particularly limited as long as it is a method for obtaining powdered cellulose from a cellulose raw material, but examples include a method that includes at least a pulverization process, and it is easy to obtain powdered cellulose with few impurities. A method in which an acid hydrolysis treatment is further performed is preferred.
　ここで、セルロース原料としては上記したものが挙げられるが、パルプを用いることが好ましく、木材由来のパルプがより好ましい。木材由来のパルプとしては、例えば、広葉樹由来のパルプ、針葉樹由来のパルプが挙げられる。木材由来のパルプの調製方法としては、例えば、パルプ化法（蒸解法）による処理を含む方法が挙げられる。パルプ化法（蒸解法）による処理により着色物質であるリグニンが溶解して取り除かれ、白色度の高いパルプを得ることができる。パルプ化法（蒸解法）としては、例えば、サルファイト蒸解法、クラフト蒸解法、ソーダ・キノン蒸解法、オルガノソルブ蒸解法が挙げられ、環境面から、クラフトパルプが好ましい。 Here, the cellulose raw materials include those mentioned above, but it is preferable to use pulp, and pulp derived from wood is more preferable. Examples of pulp derived from wood include pulp derived from broad-leaved trees and pulp derived from coniferous trees. Examples of the method for preparing wood-derived pulp include a method including a treatment using a pulping method (cooking method). The pulping method (cooking method) dissolves and removes the colored substance lignin, making it possible to obtain pulp with a high degree of whiteness. Examples of the pulping method (cooking method) include sulfite cooking, kraft cooking, soda quinone cooking, and organosolve cooking, with kraft pulp being preferred from an environmental standpoint.
　パルプの調製方法においては、パルプ化法（蒸解法）に加え、さらに漂白処理を行うことが好ましい。これにより、白色度のより高いパルプが得られる。漂白処理方法としては、例えば、任意に通常の方法で脱リグニンしたパルプに対し、塩素処理（Ｃ）、二酸化塩素漂白（Ｄ）、アルカリ抽出（Ｅ）、次亜塩素酸塩漂白（Ｈ）、過酸化水素漂白（Ｐ）、アルカリ性過酸化水素処理段（Ｅｐ）、アルカリ性過酸化水素・酸素処理段（Ｅｏｐ）、オゾン処理（Ｚ）、キレート処理（Ｑ）、及びこれらの２以上の処理の組み合わせを施す方法が挙げられる。２以上の処理の組み合わせ（シーケンス）としては、例えば、Ｄ－Ｅ／Ｐ－Ｄ、Ｃ／Ｄ－Ｅ－Ｈ－Ｄ、Ｚ－Ｅ－Ｄ－ＰＺ／Ｄ－Ｅｐ－Ｄ、Ｚ／Ｄ－Ｅｐ－ＤＰ、Ｄ－Ｅｐ－Ｄ、Ｄ－Ｅｐ－Ｄ－Ｐ、Ｄ－Ｅｐ－Ｐ－Ｄ、Ｚ－Ｅｏｐ－Ｄ－Ｄ、Ｚ／Ｄ－Ｅｏｐ－Ｄ、Ｚ／Ｄ－Ｅｏｐ－Ｄ－Ｅ－Ｄ（シーケンス中の「／」は、「／」の前後の処理を洗浄なしで連続して行なうことを意味する）が挙げられる。漂白処理は、上記の例に限定されることなく、一般的に使用される方法でもよい。漂白処理を経たパルプは、通常は流動状態（流動パルプ）である。パルプの白色度は、ＩＳＯ　２４７０に基づいて、８０％以上が好ましい。 In the pulp preparation method, in addition to the pulping method (cooking method), it is preferable to further perform a bleaching treatment. This results in a pulp with higher whiteness. Bleaching treatment methods include, for example, chlorine treatment (C), chlorine dioxide bleaching (D), alkali extraction (E), hypochlorite bleaching (H), Hydrogen peroxide bleaching (P), alkaline hydrogen peroxide treatment stage (Ep), alkaline hydrogen peroxide/oxygen treatment stage (Eop), ozone treatment (Z), chelation treatment (Q), and two or more of these treatments One example is a method of applying a combination. Examples of combinations (sequences) of two or more processes include D-E/P-D, C/D-E-HD, Z-E-D-PZ/D-Ep-D, and Z/D- Ep-DP, D-Ep-D, D-Ep-DP, D-Ep-PD, Z-Eop-DD, Z/D-Eop-D, Z/D-Eop-D- ED (the "/" in the sequence means that the processes before and after the "/" are performed consecutively without washing). Bleaching treatment is not limited to the above example, and may be any commonly used method. Pulp that has undergone bleaching treatment is usually in a fluid state (fluid pulp). The whiteness of the pulp is preferably 80% or more based on ISO 2470.
　（酸加水分解処理）
　酸加水分解処理に用いる酸としては、例えば、塩酸、硫酸、硝酸等の鉱酸が挙げられる。酸濃度は、特に限定されないが、重合度及び白色度の維持の観点から、従来の粉末状セルロース製造の酸加水分解処理の際の酸濃度より低いことが好ましく、０．４～２．０Ｎがより好ましく、０．５～１．５Ｎがより好ましい。酸濃度が０．４Ｎ未満であると、酸によるセルロースの解重合が抑制されセルロースの重合度の低下を軽減できるが、微細化が困難となる場合がある。一方、２．０Ｎを超えると、セルロースの解重合が進み微細化が容易となるため、粉体流動性は向上するが、重合度の低下に伴い錠剤硬度が低下する（成形した際に、崩壊しやすくなる）場合がある。酸加水分解処理の反応条件は特に限定されないが、反応温度は通常８０～１００℃、反応時間は通常３０分～３時間である。 (Acid hydrolysis treatment)
Examples of acids used in the acid hydrolysis treatment include mineral acids such as hydrochloric acid, sulfuric acid, and nitric acid. The acid concentration is not particularly limited, but from the viewpoint of maintaining the degree of polymerization and whiteness, it is preferably lower than the acid concentration in the conventional acid hydrolysis treatment for producing powdered cellulose, and is preferably 0.4 to 2.0N. More preferably, 0.5 to 1.5N is more preferable. When the acid concentration is less than 0.4N, depolymerization of cellulose due to acid is suppressed and a decrease in the degree of polymerization of cellulose can be reduced, but it may be difficult to refine the cellulose. On the other hand, if it exceeds 2.0N, the depolymerization of cellulose progresses and it becomes easier to refine the powder, improving powder fluidity, but tablet hardness decreases as the degree of polymerization decreases (disintegration occurs during molding). It may be easier to do so.) The reaction conditions for the acid hydrolysis treatment are not particularly limited, but the reaction temperature is usually 80 to 100°C, and the reaction time is usually 30 minutes to 3 hours.
　酸加水分解処理に先立ち、セルロース原料について前処理を行ってもよい。例えば、セルロース原料のスラリー化（分散液の調製）、セルロース原料濃度の調整が挙げられる。セルロース原料の濃度は、通常、分散液に対し３～１０重量％（固形分換算）である。セルロース原料が漂白処理を経た流動パルプの場合、通常、加水分解前にパルプ濃度を高める処理を行うことが多い。セルロース原料濃度の調整（濃縮）には、スクリュープレス、ベルトフィルター等の脱水機を用いてもよい。酸加水分解処理は、セルロース原料のスラリーに対して行われてもよいが、シート状のセルロース原料に対し行われてもよい。セルロース原料がパルプのドライシートの場合、通常、パルプをほぐしてから酸加水分解処理を行う。パルプをほぐす際には、ロールクラッシャー等の解砕機を用いてもよい。 Prior to the acid hydrolysis treatment, the cellulose raw material may be pretreated. Examples include slurrying the cellulose raw material (preparation of a dispersion) and adjusting the concentration of the cellulose raw material. The concentration of the cellulose raw material is usually 3 to 10% by weight (based on solid content) based on the dispersion. When the cellulose raw material is a fluidized pulp that has undergone bleaching treatment, a treatment to increase the pulp density is usually performed before hydrolysis. A dehydrator such as a screw press or a belt filter may be used to adjust (concentrate) the cellulose raw material concentration. The acid hydrolysis treatment may be performed on a slurry of cellulose raw material, or may be performed on a sheet-shaped cellulose raw material. When the cellulose raw material is a dry sheet of pulp, the acid hydrolysis treatment is usually performed after the pulp is loosened. When loosening the pulp, a crusher such as a roll crusher may be used.
　（中和・洗浄・脱液・乾燥処理）
　加水分解処理後、得られる処理物は、粉砕処理の前に適宜前処理を経る。前処理としては例えば、中和、洗浄、脱液、乾燥処理が挙げられ、中和、洗浄、脱液、乾燥処理をこの順に行うことが好ましい。中和処理は、アルカリ剤を添加して行えばよい。脱液処理は通常は固液分離処理であり、加水分解処理物から廃酸を分離できる。さらに、加水分解物は、乾燥（脱水）処理を経てもよい。これにより、固形分濃度を調整でき、粉末状セルロースの物性値の制御が容易にできる。固形分濃度は、通常、１５％以上、好ましくは２０％以上に調整される。乾燥は、気流式乾燥機を用いることが好ましい。これにより、加水分解後の処理物がケーキ状固体、スラリー、溶液等の態様にかかわらず、これらを気流中に分散しながら高速の熱風を当てることができ、かつ、ドライヤー内部の減圧効果を利用でき、瞬時に乾燥できる。また、熱風に触れる時間が極めて短いため、製品温度を低く保つことができ、熱に敏感な製品や融点の低い製品の乾燥に最適である。気流式乾燥機による乾燥の条件は特に限定されず、適宜設定できるが、一例を挙げると以下のとおりである。出口乾燥温度は、通常８０～１８０℃、好ましくは９０℃～１６０℃である。給気量は、通常１５０～３５０ｍ３／ｈ、好ましくは１６０～３２０ｍ３／ｈである。
　一方、噴霧乾燥機を用いる場合、噴霧し熱風で瞬時に乾燥させ顆粒物を生成する。そのため、水分量が少ない固形状・半固形状の対象物の乾燥には適さないことが多く、気流式乾燥機による乾燥よりも粒子が瞬間的に高熱に暴露されやすく、製品への影響が懸念される。 (Neutralization, cleaning, deliquification, drying treatment)
After the hydrolysis treatment, the resulting treated product undergoes an appropriate pretreatment before being pulverized. Examples of the pretreatment include neutralization, washing, deliquification, and drying treatment, and it is preferable to perform neutralization, washing, deliquification, and drying treatment in this order. The neutralization treatment may be performed by adding an alkaline agent. The deliquid treatment is usually a solid-liquid separation treatment, and waste acid can be separated from the hydrolyzed product. Furthermore, the hydrolyzate may undergo a drying (dehydration) treatment. Thereby, the solid content concentration can be adjusted and the physical properties of the powdered cellulose can be easily controlled. The solid content concentration is usually adjusted to 15% or more, preferably 20% or more. For drying, it is preferable to use a flash dryer. As a result, regardless of whether the processed material after hydrolysis is a cake-like solid, slurry, solution, etc., it is possible to apply high-speed hot air to the product while dispersing it in the air stream, and also to utilize the depressurizing effect inside the dryer. It can be dried instantly. In addition, since the exposure time to hot air is extremely short, the product temperature can be kept low, making it ideal for drying products that are sensitive to heat or products with low melting points. The conditions for drying using a flash dryer are not particularly limited and can be set as appropriate, but an example is as follows. The outlet drying temperature is usually 80 to 180°C, preferably 90 to 160°C. The amount of air supplied is usually 150 to 350 m 3 /h, preferably 160 to 320 m 3 /h.
On the other hand, when using a spray dryer, the product is sprayed and instantly dried with hot air to produce granules. Therefore, it is often not suitable for drying solid or semi-solid objects with low moisture content, and the particles are more likely to be exposed to high heat instantaneously than when drying with a flash dryer, which may affect the product. be done.
　（未変性パルプの機械的粉砕による粉末化処理）
　また、必要に応じて前工程を経た処理物を機械的粉砕することにより未変性パルプの粉末化処理を行ってもよい。粉砕と同時、又は粉砕後に、分級処理を行ってもよい。未変性パルプの粉末化処理に用いる粉砕機としては、特に制限なく用いることができるが、ジョークラッシャー（株式会社マキノ製）、パルベライザ（ホソカワミクロン株式会社製）、スーパーミクロンミル（ホソカワミクロン株式会社製）、トルネードミル（日機装株式会社製）、自由粉砕機（株式会社奈良機械製作所製）、ターボミル（フロイント産業株式会社製）、スパーパウダーミル（株式会社西村機械製作所製）、ブレードミル（日清エンジニアリング株式会社製）、超音速ジェットミル（日本ニューマチック工業株式会社製）、又はカレントジェット（日清エンジニアリング株式会社製）を用いることが好ましい。 (Powdering treatment by mechanical crushing of unmodified pulp)
Further, if necessary, the unmodified pulp may be pulverized by mechanically pulverizing the processed material that has undergone the previous step. A classification process may be performed simultaneously with the pulverization or after the pulverization. The crusher used for the powdering treatment of unmodified pulp can be used without any particular restrictions, but examples include a jaw crusher (manufactured by Makino Co., Ltd.), a pulverizer (manufactured by Hosokawa Micron Co., Ltd.), a super micron mill (manufactured by Hosokawa Micron Co., Ltd.), Tornado mill (manufactured by Nikkiso Co., Ltd.), Jiyu crusher (manufactured by Nara Kikai Seisakusho Co., Ltd.), Turbo mill (manufactured by Freund Sangyo Co., Ltd.), Spar powder mill (manufactured by Nishimura Kikai Seisakusho Co., Ltd.), Blade mill (Nissin Engineering Co., Ltd.) It is preferable to use a supersonic jet mill (manufactured by Nippon Pneumatic Industries Co., Ltd.), or a current jet (manufactured by Nisshin Engineering Co., Ltd.).
　未変性パルプの粉末化処理、又は必要に応じて行う分級処理の条件は、所望の粉末状セロースが得られるように適宜設定できる。例えば、粉砕条件（例えば、処理時間、投入量）と粉末状セルロースの所望の物性とから作成した検量線を参照して、処理条件を調整できる。 The conditions for the powdering treatment of the unmodified pulp or the classification treatment performed as necessary can be appropriately set so as to obtain the desired powdered cellose. For example, the processing conditions can be adjusted with reference to a calibration curve created from the pulverization conditions (eg, processing time, input amount) and desired physical properties of the powdered cellulose.
　未変性パルプの粉末化処理の際、必要に応じて、少なくとも１つの他の成分（例えば、有機成分、無機成分）を酸加水分解処理物とともに粉砕処理に供してもよい。これにより、粉末状セルロースに機能性を付与、又は機能性を向上させることができる。他の成分の配合量は、適量を適宜選定すればよい。 When the unmodified pulp is pulverized, at least one other component (for example, an organic component, an inorganic component) may be subjected to the pulverization treatment together with the acid-hydrolyzed product, if necessary. Thereby, functionality can be imparted to the powdered cellulose or the functionality can be improved. The amounts of other components to be blended may be appropriately selected.
　粉末状セルロース製造の際には、必要に応じて、化学的処理を行ってもよい。化学的処理は、セルロース原料の重合度を大幅に損なうおそれのない処理を適宜選択できる。化学的処理の時期としては、例えば、酸加水分解処理の前、粉砕処理と同時等が挙げられるが、特に限定されない。 When producing powdered cellulose, chemical treatment may be performed as necessary. As for the chemical treatment, any treatment that does not pose a risk of significantly impairing the degree of polymerization of the cellulose raw material can be selected as appropriate. The timing of the chemical treatment includes, for example, before the acid hydrolysis treatment and at the same time as the pulverization treatment, but is not particularly limited.
　（粉砕方法）
　本発明においては、上記のセルロース系ポリマーについてビーズミルによる粉砕を行う。ここで、ビーズミルは、通常、ベッセルと呼ばれる粉砕容器と、ベッセル内に充填された粉砕メディアとしての多数のビーズと、高速回転によりビーズを撹拌するアジテータとを有する。 (Crushing method)
In the present invention, the above-mentioned cellulose-based polymer is pulverized using a bead mill. Here, a bead mill usually has a grinding container called a vessel, a large number of beads as grinding media filled in the vessel, and an agitator that stirs the beads by high-speed rotation.
　すなわち、粉砕時においては、ベッセル内に被粉砕物を投入し、アジテータが高速で回転することによりビーズが撹拌され、ビーズ同士、ビーズとベッセルの内壁、および、ビーズとアジテータがそれぞれ衝突する。この衝突に伴い、ビーズ同士の間隙、ビーズとベッセルの内壁との間隙、ビーズとアジテータとの間隙に存在する被粉砕物は、せん断力、衝撃力、摩擦力等により粉砕される。 That is, during pulverization, the material to be pulverized is placed in a vessel, and the agitator rotates at high speed to agitate the beads, causing the beads to collide with each other, the beads and the inner wall of the vessel, and the beads and the agitator, respectively. As a result of this collision, objects to be crushed existing in the gaps between the beads, the gaps between the beads and the inner wall of the vessel, and the gaps between the beads and the agitator are crushed by shearing force, impact force, frictional force, etc.
　アジテータの種類としては、特に制限はなく、ディスク型、ピン型、アニュラーギャップ型等を採用することができる。また、ベッセルの向きについても特に制限はなく、竪型または横型を採用することができる。 The type of agitator is not particularly limited, and a disk type, pin type, annular gap type, etc. can be adopted. Further, there is no particular restriction on the orientation of the vessel, and a vertical or horizontal type can be adopted.
　ビーズおよび／またはベッセルの材質は、硬度が高く、摩耗しにくい材料であれば特に制限なく用いることができるが、ジルコニア、ジルコン、安定化ジルコニア、部分安定化ジルコニア、アルミナまたは窒化ケイ素から選ばれる少なくとも１つであることが好ましい。ここで、安定化ジルコニアとしては、イットリア安定化ジルコニア、マグネシア安定化ジルコニア、カルシア安定化ジルコニア、セリア安定化ジルコニアなどが挙げられ、部分安定化ジルコニアとしては、イットリア部分安定化ジルコニア、マグネシア部分安定化ジルコニア、カルシア部分安定化ジルコニア、セリア部分安定化ジルコニアなどが挙げられる。 The material of the beads and/or vessels can be used without any particular restriction as long as it has high hardness and is resistant to wear. Preferably, there is one. Here, examples of the stabilized zirconia include yttria-stabilized zirconia, magnesia-stabilized zirconia, calcia-stabilized zirconia, ceria-stabilized zirconia, and examples of the partially-stabilized zirconia include yttria-stabilized zirconia and magnesia-stabilized zirconia. Examples include zirconia, calcia partially stabilized zirconia, and ceria partially stabilized zirconia.
　ビーズミルの装置としては、湿式ビーズミル、乾式ビーズミルに関わらず特に制限なく用いることができるが、乾式ビーズミルを用いることが好ましい。ここで、乾式ビーズミルとしては、ダイナミックミル（日本コークス工業社製）、ドライスター（アシザワ・ファインテック社製）等を例示することができる。 As a bead mill device, a wet bead mill or a dry bead mill can be used without any particular restriction, but it is preferable to use a dry bead mill. Here, examples of the dry bead mill include Dynamic Mill (manufactured by Nippon Coke Industry Co., Ltd.), Dry Star (manufactured by Ashizawa Finetech Co., Ltd.), and the like.
　また、ビーズミルによる粉砕後に分級を行うことが好ましい。分級の方法は特に限定されないが、乾式分級機を用いる方法が好ましい。乾式分級としては、気流式分級を行うことが好ましい。また、分級処理を経た粗粉については、再度ビーズミルにて粉砕を行うことが好ましい。 Furthermore, it is preferable to perform classification after pulverization using a bead mill. The classification method is not particularly limited, but a method using a dry classifier is preferred. As the dry classification, it is preferable to perform airflow classification. Further, it is preferable that the coarse powder that has been subjected to the classification treatment is pulverized again using a bead mill.
　図１は、本発明において用いることがビーズミルを含む粉砕装置の一例を示す概略図である。粉砕装置２は、原料（被粉砕物）としてのセルロース系ポリマーを粉砕するビーズミル４、ビーズミル４により粉砕されたセルロース系ポリマーの分級を行う分級機６を備えている。ここで、ビーズミル４と分級機６とは、接続部８により接続されている。また、ビーズミル４により粉砕され分級機６により分級された所定値未満の粒子径を有するセルロース系ポリマー（微粉）は、バグフィルター等により構成される製品回収部１０にて回収される。また、製品回収部１０の下流側にはブロワ１１が設けられている。ここで、図１中の矢印は、セルロース系ポリマーおよび／または空気の進行方向を示す。 FIG. 1 is a schematic diagram showing an example of a crushing device including a bead mill used in the present invention. The pulverizing device 2 includes a bead mill 4 for pulverizing a cellulose polymer as a raw material (material to be pulverized), and a classifier 6 for classifying the cellulose polymer pulverized by the bead mill 4. Here, the bead mill 4 and the classifier 6 are connected by a connecting part 8. Further, the cellulose-based polymer (fine powder) having a particle size less than a predetermined value, which has been crushed by the bead mill 4 and classified by the classifier 6, is collected in a product collection section 10 that includes a bag filter or the like. Further, a blower 11 is provided downstream of the product recovery section 10. Here, the arrows in FIG. 1 indicate the direction of movement of the cellulosic polymer and/or air.
　ビーズミル４は、粉砕容器であるベッセル１２を備え、ベッセル１２内には水平方向に設けられ図示しない駆動装置により回転可能に構成されたアジテータ１４、粉砕メディアとして多数のビーズ１６を備えている。また、ベッセル１２内に被粉砕物である原料としてのセルロース系ポリマーを供給する原料供給部１８が設けられている。なお、ベッセル１２内において丸にて図示されるものは、符号が付されていないものであってもビーズを示す。なお、粉砕装置２においては、ビーズ１６が接続部８や粗粉回収口２２を介して分級機６へ流入したり、また、原料供給部１８へ流入したりしないように構成されている。 The bead mill 4 is equipped with a vessel 12 which is a crushing container, and inside the vessel 12 is equipped with an agitator 14 which is arranged horizontally and is configured to be rotatable by a drive device (not shown), and a large number of beads 16 as crushing media. Further, a raw material supply section 18 is provided in the vessel 12 for supplying a cellulose-based polymer as a raw material to be crushed. In addition, what is illustrated by a circle in the vessel 12 indicates a bead even if no code is attached thereto. Note that the crushing device 2 is configured so that the beads 16 do not flow into the classifier 6 through the connection portion 8 or the coarse powder recovery port 22, nor flow into the raw material supply portion 18.
　分級機６は、分級されたセルロース系ポリマー（微粉）を製品回収部１０へ送出するための製品回収口２０、所定値以上の粒子径を有するセルロース系ポリマー（粗粉）をベッセル１２へ送出する粗粉回収口２２を備えている。 The classifier 6 has a product recovery port 20 for sending the classified cellulose polymer (fine powder) to the product recovery section 10, and a product recovery port 20 for sending the cellulose polymer (coarse powder) having a particle size of a predetermined value or more to the vessel 12. A coarse powder collection port 22 is provided.
　次に、セルロース系ポリマーの粉砕工程について説明する。粉砕装置２を起動させると、ビーズミル４は図示しない駆動装置によりアジテータ１４の回転を開始させる。また、ブロワ１１も起動される。アジテータ１４の回転に伴い、ビーズ１６が撹拌される。 Next, the process of pulverizing cellulose polymer will be explained. When the crushing device 2 is started, the bead mill 4 starts rotating the agitator 14 by a drive device (not shown). Further, the blower 11 is also activated. As the agitator 14 rotates, the beads 16 are agitated.
　原料供給部１８からベッセル１２内へ被粉砕物としてのセルロース系ポリマーが供給されると、ベッセル１２内において撹拌されているビーズ１６により粉砕される。すなわち、ビーズ１６が撹拌されることにより、ビーズ１６同士の衝突、ビーズ１６とベッセル１２の内壁との衝突、および、ビーズ１６とアジテータ１４との衝突が生じる。この衝突に伴い、ビーズ同士の間隙、ビーズとベッセルの内壁との間隙、ビーズとアジテータとの間隙に存在する被粉砕物であるセルロース系ポリマーは、せん断力、衝撃力、摩擦力等により粉砕される。 When the cellulose-based polymer as a material to be crushed is supplied from the raw material supply section 18 into the vessel 12, it is crushed by the beads 16 that are being stirred in the vessel 12. That is, by stirring the beads 16, collisions occur between the beads 16, collisions between the beads 16 and the inner wall of the vessel 12, and collisions between the beads 16 and the agitator 14. As a result of this collision, the cellulose-based polymer that is the object to be crushed, which exists in the gaps between the beads, the gaps between the beads and the inner wall of the vessel, and the gaps between the beads and the agitator, is crushed by shear force, impact force, frictional force, etc. Ru.
　ベッセル１２内において粉砕されたセルロース系ポリマーは、接続部８を介して分級機６へ送出される。そして、分級機６による分級が行われ、所定値未満の粒子径を有するセルロース系ポリマー（微粉）は製品回収口２０を介して製品回収部１０へ送出される。また、所定値以上の粒子径を有するセルロース系ポリマー（粗粉）は、粗粉回収口２２を介してビーズミル４のベッセル１２へ供給され、ビーズミル４による粉砕処理に供される。 The cellulose-based polymer pulverized in the vessel 12 is sent to the classifier 6 via the connection part 8. Then, classification is performed by the classifier 6, and the cellulose polymer (fine powder) having a particle size smaller than a predetermined value is sent to the product recovery section 10 via the product recovery port 20. Further, the cellulose-based polymer (coarse powder) having a particle diameter of a predetermined value or more is supplied to the vessel 12 of the bead mill 4 through the coarse powder collection port 22 and subjected to a pulverization process by the bead mill 4 .
　本発明においてビーズミルに用いるビーズの平均直径（ビーズ径）は、０．１～１０ｍｍ、好ましくは３～８ｍｍである。ビーズの粒径が大きすぎると、得られるサンプルの粒子径が大きくなってしまうという問題が生じる。また、ビーズの粒径が小さすぎると得られるサンプルの粘度が低くなってしまうという問題が生じる。 In the present invention, the average diameter (bead diameter) of the beads used in the bead mill is 0.1 to 10 mm, preferably 3 to 8 mm. If the particle size of the beads is too large, a problem arises in that the particle size of the obtained sample becomes large. Furthermore, if the particle size of the beads is too small, a problem arises in that the viscosity of the sample obtained becomes low.
　また、ベッセル内に充填されるビーズの充填率は、５０～９０ｖｏｌ％、好ましくは７０～９０ｖｏｌ％である。ビーズの充填率が大きすぎるとコンタミを生じやすくなるという問題が生じる。また、ビーズの充填率が小さすぎると生産性が低くなるという問題が生じる。 Furthermore, the filling rate of beads filled in the vessel is 50 to 90 vol%, preferably 70 to 90 vol%. If the filling rate of beads is too large, a problem arises in that contamination is likely to occur. Moreover, if the filling rate of beads is too small, there will be a problem that productivity will be low.
　また、アジテータの周速は、２～１５ｍ／ｓｅｃ、好ましくは６～１５ｍ／ｓｅｃである。アジテータの周速が速すぎると得られるサンプルの粘度が低くなってしまうという問題が生じる。また、アジテータの周速が遅すぎると得られるサンプルの粒子径が大きくなってしまうという問題が生じる。 Further, the peripheral speed of the agitator is 2 to 15 m/sec, preferably 6 to 15 m/sec. If the circumferential speed of the agitator is too high, a problem arises in that the viscosity of the sample obtained becomes low. Further, if the circumferential speed of the agitator is too slow, a problem arises in that the particle size of the sample obtained becomes large.
　また、本発明において、原料供給部１８から供給されるセルロース系ポリマーの供給量は、３０～１５０ｋｇ／ｈであることが好ましく、４０～１２０ｋｇ／ｈであることがより好ましい。供給量が多すぎると、得られるサンプルの粒子径が大きくなってしまうという問題が生じる。また、供給量が少なすぎると得られるサンプルの粘度が低くなってしまうという問題が生じる。 Furthermore, in the present invention, the amount of cellulose polymer supplied from the raw material supply section 18 is preferably 30 to 150 kg/h, more preferably 40 to 120 kg/h. If the supply amount is too large, a problem arises in that the particle size of the obtained sample becomes large. Furthermore, if the supply amount is too small, a problem arises in that the viscosity of the sample obtained becomes low.
　本発明においては、ビーズミルのビーズの時流系、ベッセル内に充填されるビーズの充填率、アジテータの周速が上記範囲であることにより上記範囲を満たすことにより、粒子径が５０μｍ以下であるセルロース系ポリマーを安定して製造することができる。ここで、粒子径は、粒ゲージ（グラインドゲージ）により求めた最大粒子径（Ｄｍａｘ）を示す。具体的には、ＪＩＳ　Ｋ５６００およびＪＩＳ　Ｋ５４００（１９９０）に準拠してグラインドゲージにより測定された線状法の分散度から求められる最大粒子径（Ｄｍａｘ）である。 In the present invention, by satisfying the above ranges by ensuring that the flow system of beads in the bead mill, the filling rate of beads filled in the vessel, and the circumferential speed of the agitator are within the above ranges, cellulose-based particles with a particle size of 50 μm or less can be used. Polymers can be stably produced. Here, the particle diameter indicates the maximum particle diameter (D max ) determined by a grain gauge (grind gauge). Specifically, it is the maximum particle diameter (D max ) determined from the dispersity of the linear method measured with a grind gauge in accordance with JIS K5600 and JIS K5400 (1990).
　また、セルロース系ポリマーとして、化学変性されたセルロース系ポリマーを用いた場合におけるビーズミルによる粉砕を行った後のセルロース系ポリマーの２５℃でのＢ型粘度計（３０ｒｐｍ）で測定された１質量％水溶液の粘度は、好ましくは５００～１５０００ｍＰａ・ｓ、より好ましくは８００～１３０００ｍＰａ・ｓ、さらに好ましくは１０００～１００００ｍＰａ・ｓである。なお、ビーズミルによる粉砕を行った後のセルロース系ポリマーの粘度は、上述の粉砕対象のセルロース系ポリマーの粘度の測定方法と同様に測定することができる。 In addition, when a chemically modified cellulose polymer is used as the cellulose polymer, a 1% by mass aqueous solution of the cellulose polymer after pulverization with a bead mill at 25°C measured with a B-type viscometer (30 rpm) The viscosity is preferably 500 to 15,000 mPa·s, more preferably 800 to 13,000 mPa·s, and still more preferably 1,000 to 10,000 mPa·s. Note that the viscosity of the cellulose polymer after being pulverized by a bead mill can be measured in the same manner as the method for measuring the viscosity of the cellulose polymer to be pulverized described above.
　また、ビーズミルによる粉砕を行った後のセルロース系ポリマーの、０．３質量％の該セルロース系ポリマーの水溶液２リットルを－２００ｍｍＨｇの減圧条件にて２５０メッシュのフィルターですべて濾過した際のフィルター上の残渣の乾燥質量を質量Ｍとし、前記水溶液に溶解したカルボキシメチルセルロース又はその塩の質量を質量ｍとした場合に、質量ｍに対する質量Ｍの比率が５０ｐｐｍ未満であることが好ましい。５０ｐｐｍ以上であると、セルロース系ポリマーを用いてフィルムを形成した際に、フィルムにストリークやピンホールなどの外観不良が発生し、当該フィルムを使用する製品の品質が低下するおそれがある。前記質量ｍに対する前記質量Ｍの比率の下限は特に限定されず、少なければ少ないほどよい。 In addition, after pulverizing the cellulose-based polymer with a bead mill, 2 liters of a 0.3% by mass aqueous solution of the cellulose-based polymer was completely filtered through a 250 mesh filter under a reduced pressure condition of -200 mmHg. When the dry mass of the residue is mass M and the mass of carboxymethyl cellulose or its salt dissolved in the aqueous solution is mass m, the ratio of mass M to mass m is preferably less than 50 ppm. If it is 50 ppm or more, when a film is formed using a cellulose polymer, appearance defects such as streaks and pinholes may occur in the film, and the quality of products using the film may deteriorate. The lower limit of the ratio of the mass M to the mass m is not particularly limited, and the smaller the ratio, the better.
　なお、本発明の粉砕方法による粉砕を行う前に、粉砕対象のセルロース系ポリマーに対して予備粉砕を行ってもよい。予備粉砕においては、特に限定されないが、例えば衝撃式ミルを用いることができる。衝撃式ミルとしては、パルペライザ（ホソカワミクロン（株）製）、ファインイパクトミル（ホソカワミクロン（株）製）、スーパーミクロンミル（ホソカワミクロン（株）製）、サンプルミル（（株）セイシン製）、バンタムミル（（株）セイシン製）、アトマイザー（（株）セイシン製）、トルネードミル（日機装（株））、ターボミル（ターボ工業（株））、ベベルインパクター（相川鉄工（株））等が例示される。 Note that, before pulverization by the pulverization method of the present invention, the cellulose-based polymer to be pulverized may be pre-pulverized. In the preliminary crushing, for example, an impact mill can be used, although it is not particularly limited. Impact mills include Pulperizer (manufactured by Hosokawa Micron Co., Ltd.), Fine Impact Mill (manufactured by Hosokawa Micron Co., Ltd.), Super Micron Mill (manufactured by Hosokawa Micron Co., Ltd.), Sample Mill (manufactured by Seishin Co., Ltd.), and Bantam Mill (manufactured by Seishin Co., Ltd.). Examples include Seishin Co., Ltd.), an atomizer (Seishin Co., Ltd.), a tornado mill (Nikkiso Co., Ltd.), a turbo mill (Turbo Kogyo Co., Ltd.), and a bevel impactor (Aikawa Tekko Co., Ltd.).
　（用途）
　本発明のセルロース系ポリマーの粉砕方法により得られる粉砕後のセルロース系ポリマーの用途は特に制限されず、種々の用途に適用可能である。すなわち、食品、飲料、化粧品、医薬、製紙、各種化学用品、塗料、スプレー、農薬、土木、建築、電子材料、難燃剤、家庭雑貨、接着剤、洗浄剤、芳香剤、潤滑用組成物などで、増粘剤、ゲル化剤、糊剤、食品添加剤、賦形剤、塗料用添加剤、接着剤用添加剤、製紙用添加剤、研磨剤、ゴム・プラスチック用配合材料、保水剤、保形剤、泥水調整剤、ろ過助剤、溢泥防止剤などとして使用することができる。 (Application)
The use of the pulverized cellulose-based polymer obtained by the cellulose-based polymer pulverization method of the present invention is not particularly limited, and can be applied to various uses. In other words, food, beverages, cosmetics, pharmaceuticals, paper manufacturing, various chemical supplies, paints, sprays, agricultural chemicals, civil engineering, architecture, electronic materials, flame retardants, household goods, adhesives, cleaning agents, fragrances, lubricating compositions, etc. , thickeners, gelling agents, sizing agents, food additives, excipients, paint additives, adhesive additives, paper manufacturing additives, abrasives, compounded materials for rubber and plastics, water retention agents, It can be used as a filler, mud water conditioner, filter aid, mud flooding prevention agent, etc.
　たとえば、本発明のセルロース系ポリマーの粉砕方法により得られる粉砕後のセルロース系ポリマーは、リチウムイオン二次電池等の非水電解質二次電池の正極および／または負極のバインダーとして用い得る。 For example, the pulverized cellulose polymer obtained by the cellulose polymer pulverization method of the present invention can be used as a binder for the positive electrode and/or negative electrode of a nonaqueous electrolyte secondary battery such as a lithium ion secondary battery.
　上記正極および／または負極は、集電体上に電極組成物をブレード塗工、バー塗工、ダイ塗工等により積層し、加熱、乾燥、加圧等により形成することができる。ここで、電極組成物は、電極活物質、バインダーおよび必要に応じて導電材等のその他の成分を含み、バインダーとして、本発明のセルロース系ポリマーの粉砕方法により得られる粉砕後のセルロース系ポリマーを用いることができる。 The above-mentioned positive electrode and/or negative electrode can be formed by laminating an electrode composition on a current collector by blade coating, bar coating, die coating, etc., and then heating, drying, pressurizing, etc. Here, the electrode composition contains an electrode active material, a binder, and other components such as a conductive material as necessary, and as a binder, a pulverized cellulose polymer obtained by the cellulose polymer pulverization method of the present invention is used. Can be used.
　電極組成物の製造条件は特に限定はないが、例えば、上記の粉砕後のセルロース系ポリマーの水溶液または分散液に、電極組成物を構成する他の成分を添加し、必要に応じて撹拌しながら混合することにより得られる。電極組成物の性状は特に限定されず、例えば、液状、ペースト状、スラリー状などが挙げられ、いずれであってもよい。 The manufacturing conditions for the electrode composition are not particularly limited, but for example, other components constituting the electrode composition are added to the above-mentioned aqueous solution or dispersion of the pulverized cellulose-based polymer, and if necessary, while stirring. Obtained by mixing. The properties of the electrode composition are not particularly limited, and may be any of liquid, paste, and slurry forms.
　電極組成物中の電極活物質としては正極活物質または負極活物質が含まれる。正極活物質としては、ＬｉＭｅｘＯｙ（ＭｅはＮｉ、Ｃｏ、Ｍｎの少なくとも１種を含む遷移金属を意味する。ｘ、ｙは任意の数を意味する。）系の正極活物質が好ましく、ＬｉＣｏＯ２などを好ましく用いることができる。負極活物質としては、黒鉛（天然黒鉛、人造黒鉛）、コ－クス、炭素繊維のような黒鉛質材料；リチウムと合金を形成することが可能な元素（例えばＡｌ、Ｓｉ、Ｓｎ、Ａｇ、Ｂｉ、Ｍｇ、Ｚｎ、Ｉｎ、Ｇｅ、Ｐｂ、Ｔｉなど）を含む化合物；前記リチウムと合金を形成することが可能な元素及び前記化合物と、炭素及び／又は前記黒鉛質材料との複合化物；リチウムを含む窒化物などが使用できる。このうち黒鉛質材料及び又はケイ素系化合物が好ましく、黒鉛及び又はケイ素系化合物を含むことがより好ましく、ケイ素系化合物を少なくとも含むことが好ましい。 The electrode active material in the electrode composition includes a positive electrode active material or a negative electrode active material. The positive electrode active material is preferably a LiMe x O y (Me means a transition metal containing at least one of Ni, Co, and Mn. x and y represent arbitrary numbers) type positive electrode active material, LiCoO 2 or the like can be preferably used. Examples of negative electrode active materials include graphite materials such as graphite (natural graphite, artificial graphite), coke, and carbon fiber; elements that can form an alloy with lithium (for example, Al, Si, Sn, Ag, Bi , Mg, Zn, In, Ge, Pb, Ti, etc.); a composite of an element capable of forming an alloy with lithium and the compound, and carbon and/or the graphitic material; Nitrides containing nitrides, etc. can be used. Among these, graphite materials and/or silicon-based compounds are preferable, it is more preferable that graphite and/or silicon-based compounds are included, and it is preferable that at least a silicon-based compound is included.
　バインダーとして、必要に応じて、本発明のセルロース系ポリマーの粉砕方法により得られる粉砕後のセルロース系ポリマーと、スチレンブタジエンゴム（ＳＢＲ）等のゴム系結合剤とを併用してもよい。 As the binder, a pulverized cellulose polymer obtained by the cellulose polymer pulverization method of the present invention and a rubber binder such as styrene butadiene rubber (SBR) may be used in combination, if necessary.
　また、導電材としては、正極および／または負極の電気伝導性を確保し得るものを用いることができる。導電材としては、たとえば、カーボンブラック、アセチレンブラック、黒鉛等の炭素物質の１種または２種以上を混合したものが挙げられる。 Furthermore, as the conductive material, one that can ensure electrical conductivity of the positive electrode and/or negative electrode can be used. Examples of the conductive material include one or a mixture of two or more carbon substances such as carbon black, acetylene black, and graphite.
　集電体としては、構成された電池において致命的な化学変化を起こさない電気伝導体であれば何れも使用可能である。負極活物質用の集電体としては、ステンレス鋼、ニッケル、銅、チタン、炭素、銅や前記ステンレス鋼の表面にカ－ボン、ニッケル、チタンまたは銀を付着処理させたもの等が利用できる。これらのうち、銅または銅合金が好ましく、銅がより好ましい。正極用の集電体の材料としては、たとえば、アルミニウム、ステンレスなどの金属が例示され、アルミニウムが好ましい。集電体の形状としては、網、パンチドメタル、フォームメタル、板状に加工された箔などを用いることができ、板状に加工された箔が好ましい。 As the current collector, any electrical conductor that does not cause a fatal chemical change in the constructed battery can be used. As the current collector for the negative electrode active material, stainless steel, nickel, copper, titanium, carbon, copper, or stainless steel whose surface is coated with carbon, nickel, titanium, or silver can be used. Among these, copper or copper alloy is preferred, and copper is more preferred. Examples of the material for the current collector for the positive electrode include metals such as aluminum and stainless steel, with aluminum being preferred. As the shape of the current collector, a net, punched metal, foam metal, foil processed into a plate shape, etc. can be used, and foil processed into a plate shape is preferable.
　リチウムイオン二次電池等の非水電解質二次電池は、正極及び負極が交互に、セパレータを介して積層され、多数回巻回された構造を有し、正極及び負極の少なくとも一方に、本発明のセルロース系ポリマーの粉砕方法により得られる粉砕後のセルロース系ポリマーをバインダーとして含む電極を用いることができる。なお、前記セパレータは通常、非水電解質で含浸される。 A non-aqueous electrolyte secondary battery such as a lithium ion secondary battery has a structure in which positive electrodes and negative electrodes are alternately stacked with separators interposed therebetween and wound many times. An electrode containing as a binder a pulverized cellulose-based polymer obtained by the cellulose-based polymer pulverization method described above can be used. Note that the separator is usually impregnated with a nonaqueous electrolyte.
　以下、本発明の実施の形態を実施例により説明するが、本発明はこれにより限定されるものではない。
　本実施例および比較例において、セルロース系ポリマーとしてのカルボキシメチルセルロース又はその塩についての各指標の測定は以下の方法による。 Hereinafter, embodiments of the present invention will be described with reference to Examples, but the present invention is not limited thereto.
In the present Examples and Comparative Examples, each index for carboxymethylcellulose or its salt as a cellulose-based polymer was measured by the following method.
　＜カルボキシメチル置換度（ＣＭ－ＤＳ）の測定方法＞
　セルロース系ポリマーとしてのカルボキシメチルセルロース又はその塩の試料約２．０ｇを精秤して、３００ｍＬ共栓付き三角フラスコに入れた。メタノール（メタノール１０００ｍＬに特級濃硝酸１００ｍＬを加えた液）１００ｍＬを加え、３時間振とうして、カルボキシメチルセルロース塩（ＣＭＣ塩）をＨ－ＣＭＣ（カルボキシメチルセルロース）にした。絶乾したＨ－ＣＭＣを１．５～２．０ｇ精秤し、３００ｍＬ共栓付き三角フラスコに入れた。８０％メタノール１５ｍＬでＨ－ＣＭＣを湿潤し、０．１ＮのＮａＯＨを１００ｍＬ加え、室温で３時間振とうした。指示薬として、フェノールフタレインを用いて、０．１ＮのＨ２ＳＯ４で過剰のＮａＯＨを逆滴定した。ＣＭ－ＤＳを、次式１によって算出した。
（式１）
Ａ＝［（１００×Ｆ－（０．１ＮのＨ２ＳＯ４（ｍＬ））×Ｆ’）×０．１］／（Ｈ－ＣＭＣの絶乾質量（ｇ））
カルボキシメチル置換度（ＣＭ－ＤＳ）＝０．１６２×Ａ／（１－０．０５８×Ａ）
Ａ：１ｇのＨ－ＣＭＣの中和に要する１ＮのＮａＯＨ量（ｍＬ）
Ｆ’：０．１ＮのＨ２ＳＯ４のファクター
Ｆ：０．１ＮのＮａＯＨのファクター <Method for measuring degree of carboxymethyl substitution (CM-DS)>
Approximately 2.0 g of a sample of carboxymethylcellulose or its salt as a cellulose-based polymer was precisely weighed and placed in a 300 mL Erlenmeyer flask with a stopper. 100 mL of methanol (a solution of 100 mL of concentrated nitric acid added to 1000 mL of methanol) was added and shaken for 3 hours to convert the carboxymethylcellulose salt (CMC salt) to H-CMC (carboxymethylcellulose). 1.5 to 2.0 g of bone-dried H-CMC was precisely weighed and placed in a 300 mL Erlenmeyer flask with a stopper. The H-CMC was moistened with 15 mL of 80% methanol, 100 mL of 0.1 N NaOH was added, and the mixture was shaken at room temperature for 3 hours. Excess NaOH was back-titrated with 0.1 N H 2 SO 4 using phenolphthalein as an indicator. CM-DS was calculated by the following formula 1.
(Equation 1)
A = [(100 x F - (0.1 N H2SO4 ( mL )) x F') x 0.1] / (bone dry mass of H-CMC (g))
Carboxymethyl substitution degree (CM-DS) = 0.162 x A / (1 - 0.058 x A)
A: The amount of 1N NaOH required to neutralize 1 g of H-CMC (mL)
F': Factor of 0.1N H2SO4 F: Factor of 0.1N NaOH
　＜粘度＞
　セルロース系ポリマーを、１０００ｍＬ容ガラスビーカーに測りとり、蒸留水９００ｍＬに分散し、固形分１％（ｗ／ｖ）となるように水分散体を調製した。水分散体を２５℃で撹拌機を用いて６００ｒｐｍで３時間撹拌した。その後、ＪＩＳ－Ｚ－８８０３の方法に準じて、Ｂ型粘度計（東機産業社製）を用いて、Ｎｏ．４ローター／回転数３０ｒｐｍで３分後の粘度を測定した。 <Viscosity>
A cellulose-based polymer was measured into a 1000 mL glass beaker and dispersed in 900 mL of distilled water to prepare an aqueous dispersion with a solid content of 1% (w/v). The aqueous dispersion was stirred at 25° C. using a stirrer at 600 rpm for 3 hours. Thereafter, according to the method of JIS-Z-8803, using a B-type viscometer (manufactured by Toki Sangyo Co., Ltd.), No. The viscosity was measured after 3 minutes using 4 rotors/30 rpm.
　＜粒子径（粒ゲージ）＞
　粒子径は、粒ゲージ（グラインドゲージ）により測定した。具体的には、ＪＩＳ　Ｋ５６００およびＪＩＳ　Ｋ５４００（１９９０）に準拠してグラインドゲージにより測定された線状法の分散度により、最大粒子径（Ｄｍａｘ）を求めた。 <Particle size (grain gauge)>
The particle size was measured using a grain gauge (grind gauge). Specifically, the maximum particle diameter (D max ) was determined by the dispersity of the linear method measured using a grind gauge in accordance with JIS K5600 and JIS K5400 (1990).
　（実施例１）
　回転数を１００ｒｐｍに調節した二軸ニーダーに、イソプロピルアルコール１１６１ｇと水酸化ナトリウム１２１ｇを水２３１ｇに溶解したものとを加え、リンターパルプを１００℃、６０分間乾燥した際の乾燥質量で１６０ｇ仕込んだ。３０℃で９０分間攪拌、混合しマーセル化セルロースを調製した後、モノクロロ酢酸１２４ｇをイソプロピルアルコール１４２ｇに溶解したものを加え、７０℃に昇温して９０分間カルボキシメチル化反応をさせた。反応終了後、酢酸でｐＨ７程度になるよう中和し、脱液、乾燥、予備粉砕して、カルボキシメチル置換度が０．８２であり、１質量％水溶液の粘度が５，５００ｍＰａ・ｓ、粒ゲージにより求めた最大粒子径（Ｄｍａｘ）が１００μｍよりも大きい、カルボキシメチルセルロースのナトリウム塩（以下、「ＣＭＣ１」ということがある。）を得た。 (Example 1)
1161 g of isopropyl alcohol and 121 g of sodium hydroxide dissolved in 231 g of water were added to a twin-screw kneader whose rotational speed was adjusted to 100 rpm, and the dry mass of linter pulp (160 g when dried at 100° C. for 60 minutes) was charged. After stirring and mixing at 30°C for 90 minutes to prepare mercerized cellulose, a solution of 124 g of monochloroacetic acid in 142 g of isopropyl alcohol was added, and the mixture was heated to 70°C to carry out a carboxymethylation reaction for 90 minutes. After the reaction is completed, it is neutralized with acetic acid to a pH of about 7, deliquified, dried, and pre-pulverized to obtain particles with a degree of carboxymethyl substitution of 0.82, a viscosity of 1% by mass aqueous solution of 5,500 mPa・s, and particles. A sodium salt of carboxymethyl cellulose (hereinafter sometimes referred to as "CMC1") having a maximum particle diameter (D max ) determined by a gauge of more than 100 μm was obtained.
　次に得られたＣＭＣ１を図１に示すビーズミルを含む粉砕装置により粉砕した。ここで、ビーズミル４において、ビーズ径５ｍｍのジルコニアビーズを充填率８０ｖｏｌ％で用い、アジテータ１４の周速を１０ｍ／ｓｅｃとした。また、ビーズミル４のベッセル１２内へのＣＭＣ１の供給量は１２０ｋｇ／ｈであった。 Next, the obtained CMC1 was pulverized using a pulverizer including a bead mill shown in FIG. Here, in the bead mill 4, zirconia beads with a bead diameter of 5 mm were used at a filling rate of 80 vol%, and the peripheral speed of the agitator 14 was set to 10 m/sec. Further, the amount of CMC1 supplied into the vessel 12 of the bead mill 4 was 120 kg/h.
　粉砕後のＣＭＣ１の１質量％水溶液の粘度は３，３００ｍＰａ・ｓ、粒ゲージにより求めた最大粒子径（Ｄｍａｘ）は４３μｍであった。 The viscosity of the 1 mass % aqueous solution of CMC1 after pulverization was 3,300 mPa·s, and the maximum particle diameter (D max ) determined by a particle gauge was 43 μm.
　（実施例２）
　ビーズ径を８ｍｍに変更し、アジテータ１４の周速を８ｍ／ｓｅｃに変更し、また、ビーズミル４のベッセル１２内へのＣＭＣ１の供給量は４０ｋｇ／ｈに変更した以外は、実施例１と同様にＣＭＣ１の粉砕を行った。 (Example 2)
Same as Example 1 except that the bead diameter was changed to 8 mm, the peripheral speed of the agitator 14 was changed to 8 m/sec, and the amount of CMC 1 supplied into the vessel 12 of the bead mill 4 was changed to 40 kg/h. CMC1 was pulverized.
　粉砕後のＣＭＣ１の２５℃でのＢ型粘度計で測定された１質量％水溶液の粘度は３，３００ｍＰａ・ｓ、粒ゲージにより求めた最大粒子径（Ｄｍａｘ）４５μｍであった。 The viscosity of a 1% by mass aqueous solution of CMC1 after pulverization at 25° C. measured with a B-type viscometer was 3,300 mPa·s, and the maximum particle diameter (D max ) determined by a particle gauge was 45 μm.
　（実施例３）
　回転数を１００ｒｐｍに調節した二軸ニーダーに、イソプロピルアルコール１２０１ｇと水酸化ナトリウム１０１ｇを水２５５ｇに溶解したものとを加え、リンターパルプを１００℃、６０分間乾燥した際の乾燥質量で１６０ｇ仕込んだ。３０℃で９０分間攪拌、混合しマーセル化セルロースを調製した後、モノクロロ酢酸１０４ｇをイソプロピルアルコール１１８ｇに溶解したものを加え、７０℃に昇温して９０分間カルボキシメチル化反応をさせた。反応終了後、酢酸でｐＨ７程度になるよう中和し、脱液、乾燥、予備粉砕して、カルボキシメチル置換度が０．７０であり、１質量％水溶液の粘度が１４，０６０ｍＰａ・ｓ、粒ゲージにより求めた最大粒子径（Ｄｍａｘ）が１００μｍよりも大きい、カルボキシメチルセルロースのナトリウム塩（以下、「ＣＭＣ２」ということがある。）を得た。 (Example 3)
1201 g of isopropyl alcohol and 101 g of sodium hydroxide dissolved in 255 g of water were added to a twin-screw kneader whose rotation speed was adjusted to 100 rpm, and the dry mass of linter pulp (160 g when dried at 100° C. for 60 minutes) was charged. After stirring and mixing at 30°C for 90 minutes to prepare mercerized cellulose, a solution of 104 g of monochloroacetic acid in 118 g of isopropyl alcohol was added, and the mixture was heated to 70°C to carry out a carboxymethylation reaction for 90 minutes. After the reaction is completed, it is neutralized with acetic acid to a pH of about 7, deliquified, dried, and pre-pulverized to obtain particles with a degree of carboxymethyl substitution of 0.70, a viscosity of 1% by mass aqueous solution of 14,060 mPa・s, and particles. A sodium salt of carboxymethyl cellulose (hereinafter sometimes referred to as "CMC2") having a maximum particle diameter (D max ) determined by a gauge of more than 100 μm was obtained.
　次に得られたＣＭＣ２を図１に示すビーズミルを含む粉砕装置により粉砕した。ここで、ビーズミル４において、ビーズ径３ｍｍのジルコニアビーズを充填率８５ｖｏｌ％で用い、アジテータ１４の周速を１０ｍ／ｓｅｃとした。また、ビーズミル４のベッセル１２内へのＣＭＣ１の供給量は６０ｋｇ／ｈであった。 Next, the obtained CMC2 was pulverized using a pulverizer including a bead mill shown in FIG. Here, in the bead mill 4, zirconia beads with a bead diameter of 3 mm were used at a filling rate of 85 vol%, and the peripheral speed of the agitator 14 was set to 10 m/sec. Further, the amount of CMC1 supplied into the vessel 12 of the bead mill 4 was 60 kg/h.
　粉砕後のＣＭＣ２の１質量％水溶液の粘度は８，４２０ｍＰａ・ｓ、粒ゲージにより求めた最大粒子径（Ｄｍａｘ）は３７μｍであった。 The viscosity of the 1 mass % aqueous solution of CMC2 after pulverization was 8,420 mPa·s, and the maximum particle diameter (D max ) determined by a particle gauge was 37 μm.
　（実施例４）
　回転数を１００ｒｐｍに調節した二軸ニーダーに、イソプロピルアルコール１２０１ｇと水酸化ナトリウム１０１ｇを水２５５ｇに溶解したものとを加え、リンターパルプを１００℃、６０分間乾燥した際の乾燥質量で１６０ｇ仕込んだ。４０℃で１２０分間攪拌、混合しマーセル化セルロースを調製した後、モノクロロ酢酸１０４ｇをイソプロピルアルコール１１８ｇに溶解したものを加え、７０℃に昇温して９０分間カルボキシメチル化反応をさせた。反応終了後、酢酸でｐＨ７程度になるよう中和し、脱液、乾燥、予備粉砕して、カルボキシメチル置換度が０．７０であり、１質量％水溶液の粘度が１１，９４０ｍＰａ・ｓ、粒ゲージにより求めた最大粒子径（Ｄｍａｘ）が１００μｍよりも大きい、カルボキシメチルセルロースのナトリウム塩（以下、「ＣＭＣ３」ということがある。）を得た。 (Example 4)
1201 g of isopropyl alcohol and 101 g of sodium hydroxide dissolved in 255 g of water were added to a twin-screw kneader whose rotation speed was adjusted to 100 rpm, and the dry mass of linter pulp (160 g when dried at 100° C. for 60 minutes) was charged. After stirring and mixing at 40° C. for 120 minutes to prepare mercerized cellulose, a solution of 104 g of monochloroacetic acid dissolved in 118 g of isopropyl alcohol was added, and the mixture was heated to 70° C. to carry out a carboxymethylation reaction for 90 minutes. After the reaction is completed, it is neutralized with acetic acid to a pH of about 7, deliquified, dried, and pre-pulverized to obtain particles with a degree of carboxymethyl substitution of 0.70, a viscosity of 1% by mass aqueous solution of 11,940 mPa・s, and particles. A sodium salt of carboxymethyl cellulose (hereinafter sometimes referred to as "CMC3") having a maximum particle diameter (D max ) determined by a gauge of more than 100 μm was obtained.
　次に得られたＣＭＣ３を図１に示すビーズミルを含む粉砕装置により粉砕した。ここで、ビーズミル４において、ビーズ径５ｍｍのジルコニアビーズを充填率７５ｖｏｌ％で用い、アジテータ１４の周速を１２ｍ／ｓｅｃとした。また、ビーズミル４のベッセル１２内へのＣＭＣ１の供給量は８５ｋｇ／ｈであった。 Next, the obtained CMC3 was pulverized using a pulverizer including a bead mill shown in FIG. Here, in the bead mill 4, zirconia beads with a bead diameter of 5 mm were used at a filling rate of 75 vol%, and the peripheral speed of the agitator 14 was set to 12 m/sec. Further, the amount of CMC1 supplied into the vessel 12 of the bead mill 4 was 85 kg/h.
　粉砕後のＣＭＣ３の２５℃でのＢ型粘度計で測定された１質量％水溶液の粘度は８，８００ｍＰａ・ｓ、粒ゲージにより求めた最大粒子径（Ｄｍａｘ）４５μｍであった。 The viscosity of a 1% by mass aqueous solution of CMC3 after pulverization at 25° C. measured with a B-type viscometer was 8,800 mPa·s, and the maximum particle diameter (D max ) determined by a particle gauge was 45 μm.
　（比較例１）
　ビーズ径を１２ｍｍに変更し、充填率を６０ｖｏｌ％に変更し、アジテータ１４の周速を５ｍ／ｓｅｃに変更した以外は、実施例１と同様にＣＭＣ１の粉砕を行った。 (Comparative example 1)
CMC1 was pulverized in the same manner as in Example 1, except that the bead diameter was changed to 12 mm, the filling rate was changed to 60 vol%, and the peripheral speed of the agitator 14 was changed to 5 m/sec.
　粉砕後のＣＭＣ１の１質量％水溶液の粘度は３，７３０ｍＰａ・ｓ、粒ゲージにより求めた最大粒子径（Ｄｍａｘ）は７４μｍであった。
　以上の結果を、表１に示す。 The viscosity of the 1 mass % aqueous solution of CMC1 after pulverization was 3,730 mPa·s, and the maximum particle diameter (D max ) determined by a particle gauge was 74 μm.
The above results are shown in Table 1.
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
　表１に示すように、ビーズミルによるセルロース系ポリマーの粉砕方法であって、前記ビーズミルに用いるビーズの平均直径が０．１～１０ｍｍ、前記ビーズミルのアジテータの周速が２～１５ｍ／ｓｅｃ、前記ビーズミルのビーズ充填率が５０～９０ｖｏｌ％であるセルロース系ポリマーの粉砕方法によりセルロース系ポリマーの粉砕を行うと、粒子径が５０μｍ未満のセルロース系ポリマーを安定して製造することができた。 As shown in Table 1, there is provided a method for pulverizing cellulose-based polymers using a bead mill, wherein the beads used in the bead mill have an average diameter of 0.1 to 10 mm, the peripheral speed of the agitator of the bead mill is 2 to 15 m/sec, and the bead mill When a cellulose-based polymer was pulverized using a cellulose-based polymer pulverization method with a bead filling rate of 50 to 90 vol%, it was possible to stably produce a cellulose-based polymer with a particle size of less than 50 μm.
２…粉砕装置、４…ビーズミル、６…分級機、１０…製品回収部、１１…ブロワ、１２…ベッセル、１４…アジテータ、１６…ビーズ、１８原料供給部
 
  2... Grinding device, 4... Bead mill, 6... Classifier, 10... Product recovery section, 11... Blower, 12... Vessel, 14... Agitator, 16... Beads, 18 Raw material supply section

Claims (6)

  1. 　ビーズミルによるセルロース系ポリマーの粉砕方法であって、前記ビーズミルに用いるビーズの平均直径が０．１～１０ｍｍ、前記ビーズミルのアジテータの周速が２～１５ｍ／ｓｅｃ、前記ビーズミルのビーズ充填率が５０～９０ｖｏｌ％であるセルロース系ポリマーの粉砕方法。 A method of pulverizing a cellulose polymer using a bead mill, wherein the average diameter of the beads used in the bead mill is 0.1 to 10 mm, the peripheral speed of the agitator of the bead mill is 2 to 15 m/sec, and the bead filling rate of the bead mill is 50 to 10 mm. A method for pulverizing a cellulose polymer having a concentration of 90 vol%.
  2. 　前記ビーズの平均直径が３～８ｍｍである請求項１記載のセルロース系ポリマーの粉砕方法。 The method for pulverizing a cellulose polymer according to claim 1, wherein the beads have an average diameter of 3 to 8 mm.
  3. 　前記ビーズミルは乾式ビーズミルである請求項１または２記載のセルロース系ポリマーの製造方法。 The method for producing a cellulose polymer according to claim 1 or 2, wherein the bead mill is a dry bead mill.
  4. 　前記ビーズミルの前記アジテータおよび／またはベッセルの材質は、ジルコニア、ジルコン、安定化ジルコニア、部分安定化ジルコニア、アルミナまたは窒化ケイ素のうちから選ばれる少なくとも１つである請求項１または２記載のセルロース系ポリマーの粉砕方法。 The cellulosic polymer according to claim 1 or 2, wherein the material of the agitator and/or vessel of the bead mill is at least one selected from zirconia, zircon, stabilized zirconia, partially stabilized zirconia, alumina, and silicon nitride. How to grind.
  5. 　前記ビーズミルへの前記セルロース系ポリマーの供給量が３０～１５０ｋｇ／ｈである、請求項１または２に記載のセルロース系ポリマーの粉砕方法。 The method for pulverizing a cellulose-based polymer according to claim 1 or 2, wherein the amount of the cellulose-based polymer supplied to the bead mill is 30 to 150 kg/h.
  6. 　前記セルロース系ポリマーが、カルボキシメチルセルロースおよび／又はその塩である、請求項１または２に記載のセルロース系ポリマーの粉砕方法。
          The method for pulverizing a cellulose-based polymer according to claim 1 or 2, wherein the cellulose-based polymer is carboxymethylcellulose and/or a salt thereof.
PCT/JP2023/029955 2022-09-15 2023-08-21 Method for grinding cellulose polymer WO2024057830A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2022-146695 2022-09-15
JP2022146695 2022-09-15

Publications (1)

Publication Number Publication Date
WO2024057830A1 true WO2024057830A1 (en) 2024-03-21

Family

ID=90274839

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2023/029955 WO2024057830A1 (en) 2022-09-15 2023-08-21 Method for grinding cellulose polymer

Country Status (1)

Country Link
WO (1) WO2024057830A1 (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2014000574A (en) * 2009-11-13 2014-01-09 Moriroku Chemicals Co Ltd Method for manufacturing fine powder and fine powder manufactured by same method
WO2017047755A1 (en) * 2015-09-16 2017-03-23 宇部興産株式会社 Fibrous carbon-containing lithium-titanium composite oxide powder, electrode sheet using same, and power storage device using same
WO2019167961A1 (en) * 2018-02-28 2019-09-06 株式会社Ｍｉｚｋａｎ Ｈｏｌｄｉｎｇｓ Solid-oil-and-fat-containing composition, method for producing same, method for adjusting physical properties of same, and oil-and-fat hardening agent
WO2020179701A1 (en) * 2019-03-01 2020-09-10 塩野義製薬株式会社 Contaminant-depleted nanoparticle composition and method for producing same

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2014000574A (en) * 2009-11-13 2014-01-09 Moriroku Chemicals Co Ltd Method for manufacturing fine powder and fine powder manufactured by same method
WO2017047755A1 (en) * 2015-09-16 2017-03-23 宇部興産株式会社 Fibrous carbon-containing lithium-titanium composite oxide powder, electrode sheet using same, and power storage device using same
WO2019167961A1 (en) * 2018-02-28 2019-09-06 株式会社Ｍｉｚｋａｎ Ｈｏｌｄｉｎｇｓ Solid-oil-and-fat-containing composition, method for producing same, method for adjusting physical properties of same, and oil-and-fat hardening agent
WO2020179701A1 (en) * 2019-03-01 2020-09-10 塩野義製薬株式会社 Contaminant-depleted nanoparticle composition and method for producing same

Similar Documents

Publication Publication Date Title
JP6228707B1 (en) Acid-type carboxymethylated cellulose nanofiber and method for producing the same
JP7270194B2 (en) METHOD FOR MANUFACTURING DRY CELLULOSE NANOFIBER
JP5950012B1 (en) Method for producing fine fibrous cellulose-containing material
EP3095815A1 (en) Dry solid of anion-modified cellulose nanofiber and method for producing same
WO2017154568A1 (en) Method for re-dispersing cellulose nanofiber dispersion
WO2018070387A1 (en) Method for producing rubber composition
JP2021050358A (en) Method for dehydrating dispersion of chemically modified pulp
WO2024057830A1 (en) Method for grinding cellulose polymer
JP6944451B2 (en) Masterbatch manufacturing method
WO2018143150A1 (en) Method for producing dry cellulose nanofibers
WO2021112195A1 (en) Method for manufacturing modified cellulose microfibrils
WO2024057829A1 (en) Method for crushing cellulose-based polymer
WO2024057828A1 (en) Method for grinding cellulose polymer
JP7157656B2 (en) Method for producing fine fibrous cellulose dispersion
JP2016069536A (en) Producing method of cellulose nano fiber
JP2021075665A (en) Cellulose nanofiber having carboxyl group and anionic group other than carboxyl group, and method for producing the same
JP2020033531A (en) Composition containing cellulose nanofiber and starch
CN113544330B (en) Fibrillated chemically modified cellulose fibers
JP6951844B2 (en) Masterbatch manufacturing method
JP7426810B2 (en) Adhesive composition, its manufacturing method and use
JP7203484B2 (en) cheese
JP7411852B1 (en) Anion-modified cellulose nanofiber-containing powder
JPWO2019189318A1 (en) Method for producing dry cellulose nanofiber
JP2019214702A (en) Method for producing resin composite
WO2019059079A1 (en) Method for producing anionically modified cellulose nanofibers

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 23865189

Country of ref document: EP

Kind code of ref document: A1