Method for manufacturing toner

Abstract

To provide a method for manufacturing toner having good electrification characteristics even in a high humidity environment by sufficiently reducing the amount of salt present on a surface of the toner even when the surface of the toner has a carboxy group.SOLUTION: A method for manufacturing toner has a cleaning step of cleaning resin particles in cleaning liquid. The resin particle has, on its surface, a functional group -(COO-)nAn+ (in the formula, An+ represents a metal ion or an ammonium ion, and n represents an integer of 1 or more and 3 or less). The cleaning liquid contains fine bubbles. The number average particle diameter of the fine bubbles in the cleaning liquid is 1.0×101 nm or more and 1.0×105 nm or less. The zeta potential of the fine bubbles in the cleaning liquid is -60 mV or more and 0 mV or less.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a method for producing a toner used in recording methods utilizing electrophotography, electrostatic recording, and toner jet recording. [Background technology]

[0002] In recent years, the environments in which printers and copiers using electrophotography are used have become more diverse, and toners are required to exhibit stable performance even under these various operating environments. In order to obtain stable images in electrophotography, it is necessary to precisely control the chargeability of the toner. To control the charge amount of the toner, negatively chargeable toners have been investigated, and toners having functional groups such as carboxyl groups or sulfonic acid groups on the toner surface have been investigated, and positively chargeable toners have been investigated, and these functional groups have excellent charge transfer performance due to friction, and can therefore improve the chargeability of the toner. As such, the chargeability of toner is greatly affected by the materials that make up the toner. In addition, the chargeability of toner is affected by the ambient humidity, and the charge amount tends to decrease, especially in high-humidity environments. This is thought to be because the adsorption of water molecules to the toner surface reduces the resistivity of the toner surface, making it easier for charge to leak. In order to suppress the adsorption of water molecules to the toner surface, it is necessary to control the amount of hydrophilic substances present on the toner surface. In particular, with toners manufactured in aqueous media, salts formed by the bonding of cations such as metal ions in the aqueous medium with acid groups such as carboxyl groups present on the toner surface tend to remain on the toner surface. Because salts are generally hydrophilic substances, there was a problem in that the charge amount decreased due to salts remaining on the toner surface. Patent Document 1 discloses a method for producing toner, which includes a step of subjecting a toner particle dispersion to a reslurry washing treatment with an alkaline solution having a pH of 8 to 12, and a step of subjecting a toner particle dispersion to a reslurry washing treatment with an acidic solution having a pH of 2 to 6. Patent Document 2 also discloses a washing method in which an ionic liquid is used as a washing aid in washing toner particles. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-113112 [Patent Document 2] Japanese Patent Application Laid-Open No. 2012-198518 Summary of the Invention [Problem to be solved by the invention]

[0004] However, it has been confirmed that in the method disclosed in Patent Document 1, counter ions of the alkali and acid used remain in the toner, which deteriorates the chargeability in a high humidity environment. Furthermore, the method disclosed in Patent Document 2 uses an ionic liquid to remove production reactants, including surfactants and ions, that are absorbed on the toner surface and inside the toner. However, this method does not sufficiently reduce the amount of metal on the surface, and it has been confirmed that trace amounts of the ionic liquid that was used remain, which deteriorates the charging properties in a high-humidity environment, just as in Patent Document 1. As described above, conventional studies have not been able to sufficiently reduce the amount of salt present on the toner surface, and there have been problems with chargeability in high humidity environments. The present invention solves the above-mentioned problems and provides a method for producing a toner that has good chargeability even in a high-humidity environment by sufficiently reducing the amount of salt present on the toner surface, even when the toner surface has a carboxy group. [Means for solving the problem]

[0005] The toner manufacturing method of the present invention is a toner manufacturing method including a washing step of washing resin particles with a washing liquid, The resin particles have functional groups -(COO-) on the surface. n A n+ (In the formula, A n+ represents a metal ion or an ammonium ion, and n represents an integer of 1 or more and 3 or less, The cleaning solution contains fine bubbles, The number average particle size of the fine bubbles in the cleaning solution is 1.0 × 10 1 nm or more 1.0×10 5 nm or less, The toner manufacturing method is characterized in that the zeta potential of the fine bubbles in the cleaning solution is -60 mV or more and 0 mV or less. [Effects of the Invention]

[0006] According to the present invention, even when the toner surface has a carboxy group, by sufficiently reducing the amount of salt present on the toner surface, it is possible to provide a method for producing a toner that has good chargeability even in a high-humidity environment. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic diagram of a Faraday cage. DETAILED DESCRIPTION OF THE INVENTION

[0008] In the present invention, unless otherwise specified, the expressions "xx or more and xx or less" and "xx to xx" representing a numerical range mean a numerical range including the lower and upper limits, which are the endpoints.

[0009] [Features of the present invention] The toner manufacturing method of the present invention is a toner manufacturing method including a washing step of washing resin particles with a washing liquid, The resin particles have functional groups -(COO - ) n A n+ (In the formula, A n+ represents a metal ion or an ammonium ion, and n represents an integer of 1 or more and 3 or less, The cleaning solution contains fine bubbles, The number average particle size of the fine bubbles in the cleaning solution is 1.0 × 10 1 nm or more 1.0×10 5 nm or less, The zeta potential of the fine bubbles in the cleaning solution is -60 mV or more and 0 mV or less.

[0010] The reason why the toner manufacturing method of the present invention can sufficiently reduce the amount of salt present on the toner surface and, as a result, can manufacture a toner having good charging properties even in a high-humidity environment is not clear, but the inventors speculate as follows.

[0011] The resin particles of the present invention are toner precursors, and after a washing process, the toner is obtained through processes such as drying, classification, and external addition, as necessary. Therefore, the surface of the resin particles at least partially forms the surface of the final toner. Therefore, the surface condition of the resin particles has a significant impact on the charge state of the toner. As mentioned above, the amount of salt on the toner surface affects the chargeability, so reducing the amount of salt on the resin particle surface leads to an improvement in the chargeability of the toner.

[0012] The resin particles of the present invention have a carboxyl group (-COO - H + ) hydrogen ions (H + ) is A n+ In order to remove this salt, it is necessary to convert the cation back to a hydrogen ion and return it to its original carboxyl group. In general cleaning with water, the cleaning process proceeds by using the hydrogen ions contained in the water to convert the cation to a hydrogen ion. However, in a neutral aqueous medium, the hydrogen ion concentration [H + ] is 1.0 × 10 -7 (mol / L), and the functional group -(COO - ) n A n+ As the amount of cations decreases, the equilibrium shifts to the salt side, making cleaning difficult. Thus, in order to achieve a certain level of cleaning effectiveness, it is necessary to more actively promote the dissociation of cations and carboxyl groups.

[0013] Here, the inventors focused on aqueous media containing fine bubbles. It is known that in aqueous media containing fine bubbles (bubbles with a diameter of less than 100 μm), hydroxide ions are oriented around the fine bubbles, resulting in the fine bubbles having a negative zeta potential. Since the hydrogen ion concentration and hydroxide ion concentration are equal in a neutral aqueous medium, it is assumed that fine bubbles have a structure in which the hydroxide ion concentration is high in the vicinity, and the hydrogen ion concentration is even higher in the vicinity of those bubbles.

[0014] In the present invention, the cleaning effect is achieved by utilizing the interaction between this structure and the positive charge of the cation. First, the cation is liberated from the carboxyl group due to the interaction between the negative charge of the fine bubble and the cation. Next, the liberated cation binds with hydroxide ions near the fine bubble and is removed from the system. In parallel, hydrogen ions present around the fine bubble are supplied to the liberated carboxyl group of the cation, completing the cleaning process. Since no other ions are involved in the above cleaning process, the chargeability of the toner is not affected. This allows for the production of toner with excellent chargeability.

[0015] The present invention will be described in detail below.

[0016] [Fine Bubbles] The cleaning solution of the present invention contains fine bubbles. The fine bubbles and the cleaning solution of the present invention are described in detail below.

[0017] <Physical properties of fine bubbles> The number-average particle size of the fine bubbles of the present invention is 1.0 × 10 1 nm or more 1.0×10 5 When the number-average particle diameter of the fine bubbles is within the above range, the fine bubbles can easily approach the resin particles, thereby achieving a high cleaning effect. The number-average particle diameter of the fine bubbles of the present invention is 1.0 × 10 1 nm or more 1.0×10 3It is preferable that the number-average particle diameter of the fine bubbles is 5.0 × 10 nm or less. When the number-average particle diameter of the fine bubbles is within the above range, the fine bubbles can be stably present in the aqueous medium for a long period of time. Therefore, it is possible to obtain a stable and high cleaning effect. The number-average particle diameter of the fine bubbles of the present invention is 5.0 × 10 1 nm or more 5.0×10 2 It is more preferably nm or less.

[0018] Methods for controlling the number-average particle size of fine bubbles include changing the production conditions of fine bubbles and membrane separation, which separates the generated fine bubbles using a membrane.Membrane separation involves dropping a cleaning solution containing fine bubbles into multiple filters with pores of the desired diameter, thereby separating and classifying the bubbles into those of the desired diameter.

[0019] The zeta potential of the fine bubbles of the present invention is between -60 mV and 0 mV. A zeta potential within this range indicates that hydroxide ions are oriented on the surface of the fine bubbles, creating a concentration gradient of hydrogen ions and hydroxide ions in the cleaning solution. Therefore, as described above, the cation removal effect can be achieved. The zeta potential of the fine bubbles of the present invention is preferably -10 mV or less. When the zeta potential of the fine bubbles is within this range, the concentration gradient of hydrogen ions and hydroxide ions in the cleaning solution is strengthened, further improving the cleaning effect. Furthermore, the zeta potential of the fine bubbles of the present invention is preferably -30 mV or more. When the zeta potential of the fine bubbles is within this range, it is possible to suppress repulsion between the fine bubbles and the resin particles while maintaining sufficient cation removal effect, thereby further improving the cleaning effect. Furthermore, since the fine bubbles are more likely to adsorb to the surface of the resin particles, the insulating effect of the fine bubbles present on the surface of the toner precursor resin particles makes the resin particles less susceptible to thermal history, even when a drying process involving heating is performed after the cleaning process. Therefore, it is possible to prevent deterioration of transferability and developability and contamination of components during the development process due to the exudation of release agents, plasticizers, etc. that should be contained in the toner onto the toner surface.

[0020] Methods for controlling the zeta potential of fine bubbles include changing the type of gas that makes up the fine bubbles or changing the pH of the cleaning solution.

[0021] The number concentration of fine bubbles in the present invention is 1.0 x 10 4 Preferably, the number of cells / mL or more is 1.0 x 10 6 When the concentration of fine bubbles of the present invention is within the above range, a sufficient cleaning effect can be obtained with a small amount of cleaning liquid, thereby improving the cleaning efficiency.

[0022] Methods for controlling the number concentration of fine bubbles include concentration using the membrane separation method described above, changing the fine bubble production conditions, and dilution by adding an aqueous medium.

[0023] <Method for measuring the physical properties of fine bubbles> The physical properties of the fine bubbles described above are measured as follows.

[0024] [Number-average particle size and number concentration of fine bubbles] The number-average particle size and number concentration of fine bubbles are measured as follows using a particle size measuring device, ViewSizer 3000 (manufactured by HORIBA), which utilizes the particle tracking method.

[0025] Prepare an aqueous medium containing fine bubbles as the sample. Inject 2 ml of the measurement sample into a quartz cell (High Precision Cell: Hellma Analytic, 10 x 10 mm) equipped with the stir bar and dedicated jig provided with the instrument, and then place the cell in the instrument's cell holder. Launch Nano Tracking Analysis from the application provided with the instrument and perform measurements using the following settings. Target temperature: 22 #of videos:30 Frames per second: 30 Exposure: 18 Gain:24 Stirring time:5 Video length:300 Laser power B:70 G:12 R:8

[0026] After the measurement is completed, the Average size value (nm) on the displayed measurement results screen is the number-average particle size of the fine bubbles, and the Particle Concentration value (particles / mL) is the number concentration of the fine bubbles.

[0027] When measuring, turn stirring on in Streaming mode and check that the outlines of the fine bubbles on the image displayed are clear, and with stirring off, check that there is little overlap between the fine bubbles on the image. If the outlines are unclear, use the Focus function to adjust the focus. If there is significant overlap between the fine bubbles, dilute the sample. If the sample is diluted, multiply the obtained Particle Concentration value by the dilution factor to obtain the fine bubble number concentration.

[0028] [Zeta potential of fine bubbles] The zeta potential of fine bubbles is measured as follows using a zeta potential measuring device, ZetaSizer Nano ZSP (manufactured by Malvern), which utilizes electrophoretic light scattering.

[0029] Prepare an aqueous medium containing fine bubbles as a sample. Fill a disposable capillary cell (DTS1060, manufactured by Malvern) for zeta potential measurement with the measurement sample, and set the cell in the instrument's cell holder. Select "Zeta potential measurement" from the application provided with the instrument, and perform the measurement under the following conditions. F(ka)selection Model: Smoluchowski Dispersant:Water Temperature: 25℃ Result Calculation:General Purpose

[0030] After the measurement is completed, the "Zeta Potential" value (mV) displayed on the measurement results report screen is the zeta potential of the fine bubbles.

[0031] <Fine bubble manufacturing method> The method for producing fine bubbles of the present invention can be any conventionally known method without any particular limitations. Specific examples include methods based on gas phase dispersion by liquid flow shear, such as swirling liquid flow, static mixer, mechanical shear, micropore, and fluid vibration methods; methods based on changes in gas solubility in liquid, such as pressurized dissolution and thermal precipitation; methods based on cavitation, such as ejector, Venturi, and ultrasonic methods; methods based on phase changes in the dispersed phase, such as mixed vapor condensation; and methods based on chemical changes in the liquid phase, such as electrolysis.

[0032] Among these, methods based on cavitation are preferred because they enable efficient fine bubble generation. Below, a Venturi-type fine bubble production method will be described in detail as an example of a method based on cavitation, but the present invention is not limited to the following.

[0033] In the Venturi-type fine bubble manufacturing method, a liquid containing the target gas dissolved in it is fed into a Venturi tube with a constricted section. As the liquid passes through the constricted section, its flow rate increases, causing it to be decompressed according to Bernoulli's theorem. When the pressure drops below the saturated vapor pressure of the gas, bubbles are generated in the liquid due to cavitation. After passing through the constricted section, the liquid is re-pressurized as the flow rate decreases, and the generated bubbles collapse under the pressure, generating fine bubbles.

[0034] [Cleaning solution] The cleaning solution of the present invention can be any cleaning solution containing the above-mentioned fine bubbles, without any particular limitations. Among these, it is preferable that the cleaning solution be a cleaning solution produced by the above-mentioned fine bubble production method using an aqueous medium containing 95% by mass or more of water as the main component. Furthermore, because the content of ions other than hydrogen ions and hydroxide ions is low, it is even more preferable that the cleaning solution be a cleaning solution produced by the above-mentioned fine bubble production method using ion-exchanged water or RO water obtained by reverse osmosis as the raw material.

[0035] The temperature of the cleaning solution is preferably 30°C to 50°C, and more preferably 35°C to 45°C. When the temperature of the cleaning solution is within this range, the efficiency of cation removal is improved. In general cleaning, the higher the temperature of the cleaning solution, the higher the cleaning efficiency. This is because the solubility and dispersibility of the object to be cleaned increase with temperature. On the other hand, in cleaning solutions containing fine bubbles, the cleaning efficiency is determined by the interaction between the object to be cleaned and the fine bubbles. The fine bubble concentration correlates with the solubility of gas in the liquid, and gas solubility is generally higher at lower temperatures. Therefore, it is speculated that the temperature of the cleaning solution suitable for the cleaning method of the present invention has a peak, and that cleaning efficiency is maximized at a temperature where both the solubility and dispersibility of the object to be cleaned and the solubility of gas increase.

[0036] Next, the resin particles used in the present invention will be described in detail below.

[0037] [Resin particles] The resin particles of the present invention are precursors of toner.

[0038] The resin particles of the present invention have a functional group -(COO - ) n A n+ (In the formula, A n+ represents a metal ion or an ammonium ion, and n represents an integer of 1 or more and 3 or less. - ) n A n+is preferably a salt formed between a carboxy group of the carboxy group-containing resin present on the surface of the resin particle and a metal ion or an ammonium ion, and more preferably a salt formed between a carboxy group of the carboxy group-containing resin present on the surface of the resin particle and a metal ion.

[0039] <Carboxy group-containing resin> The carboxyl group-containing resin of the present invention can be used as a binder resin when a toner is obtained via resin particles.

[0040] The carboxyl group-containing resin of the present invention can be any known carboxyl group-containing resin without any particular limitation. Among them, a carboxyl group-containing resin having an acid value of 1.00 mgKOH / g or more and 50.00 mgKOH / g or less is preferably used, and more preferably a carboxyl group-containing resin having an acid value of 2.50 mgKOH / g or more and 30.00 mgKOH / g or less, because it is easy to control the acid value of the resin particle surface to 0.02 mgKOH / g or more and 1.00 mgKOH / g or less.

[0041] Specific examples of the resin include carboxyl group-containing polyester resins, vinyl resins, polyurethane resins, polyamide resins, etc. Among these, polyester resins and vinyl resins are preferred because the hydrophilicity of the resin can be easily adjusted to an appropriate range and the adsorption of fine bubbles to resin particles can be easily increased.

[0042] <Polyester resin> The polyester resin can be obtained by selecting and combining suitable compounds from polycarboxylic acids, polyols, hydroxycarboxylic acids, etc., and synthesizing them using a conventionally known method such as transesterification or polycondensation.

[0043] Polycarboxylic acids are compounds containing two or more carboxy groups in one molecule. Among them, dicarboxylic acids are compounds containing two carboxy groups in one molecule and are preferably used. Note that the following polycarboxylic acids may be used as derivatives such as anhydrides, halides, esters, and amides, if necessary.

[0044] Examples of dicarboxylic acids include aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, tetrachlorophthalic acid, chlorophthalic acid, nitrophthalic acid, p-carboxyphenylacetic acid, p-phenylenediacetic acid, m-phenylenediacetic acid, o-phenylenediacetic acid, naphthalene-1,4-dicarboxylic acid, naphthalene-1,5-dicarboxylic acid, naphthalene-2,6-dicarboxylic acid, and anthracenedicarboxylic acid; linear aliphatic saturated dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, sebacic acid, azelaic acid, nonanedicarboxylic acid, decanedicarboxylic acid, undecanedicarboxylic acid, and dodecanedicarboxylic acid; fumaric acid, maleic acid, and glutaconic acid. Examples of suitable dicarboxylic acids include linear aliphatic unsaturated dicarboxylic acids such as β-methyladipic acid and n-dodecylsuccinic acid; branched aliphatic unsaturated dicarboxylic acids such as citraconic acid, itaconic acid, and n-dodecenylsuccinic acid; heteroatom-containing dicarboxylic acids such as diglycolic acid; alicyclic saturated dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, and 2,3-norbornanedicarboxylic acid; and alicyclic unsaturated dicarboxylic acids such as cis-4-cyclohexene-1,2-dicarboxylic acid and cis-5-norbornene-endo-2,3-dicarboxylic acid. Among these, aromatic dicarboxylic acids or linear aliphatic saturated dicarboxylic acids are preferred, with aromatic dicarboxylic acids being more preferred. These may be used alone or in combination.

[0045] Examples of polycarboxylic acids other than dicarboxylic acids include tricarboxylic acids such as trimellitic acid, trimesic acid, naphthalenetricarboxylic acid, and pyrenetricarboxylic acid; and tetracarboxylic acids such as pyromellitic acid, naphthalenetetracarboxylic acid, and pyrenetetracarboxylic acid. These may be used alone or in combination of two or more. For the purpose of adjusting the acid value of the resin, it is preferable to use a polycarboxylic acid having a valence of three or more.

[0046] Polyols are compounds containing two or more hydroxyl groups in one molecule, and among these, diols are compounds containing two hydroxyl groups in one molecule and are preferably used.

[0047] Specifically, the above-mentioned bisphenols, such as bisphenol A, bisphenol F, and bisphenol S, and their alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adducts; ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, and 1,18-octadecanediol, etc. Examples of suitable diols include linear aliphatic saturated diols such as 1,2-propylene glycol and neopentyl glycol; branched aliphatic saturated diols such as diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, and polytetramethylene ether glycol; heteroatom-containing linear diols such as diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, and polytetramethylene ether glycol; cyclic aliphatic saturated diols such as 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, and hydrogenated bisphenol A; linear aliphatic unsaturated diols such as 1,4-butenediol; and heteroatom-containing cyclic diols such as isosorbide. Among these, linear aliphatic saturated diols, alkylene oxide adducts of bisphenols, and heteroatom-containing cyclic diols are preferred. These may be used alone or in combination of two or more.

[0048] Examples of trihydric or higher polyols include triols such as glycerin, trimethylolethane, and trimethylolpropane; tetraols such as pentaerythritol; and hexaols such as dipentaerythritol and sorbitol. These may be used alone or in combination of two or more.

[0049] <Vinyl resin> Examples of vinyl resins that can be used include polymers or copolymers of vinyl monomers such as styrene monomers typified by styrene, α-methylstyrene, and divinylbenzene; unsaturated carboxylic acid esters typified by methyl acrylate, butyl acrylate, methyl methacrylate, 2-hydroxyethyl methacrylate, t-butyl methacrylate, 2-ethylhexyl methacrylate, lauryl acrylate, lauryl methacrylate, stearyl acrylate, stearyl methacrylate, and 1,6-hexanediol diacrylate; unsaturated carboxylic acids typified by acrylic acid and methacrylic acid; unsaturated dicarboxylic acids typified by maleic acid; unsaturated dicarboxylic acid anhydrides typified by maleic anhydride; nitrile vinyl monomers typified by acrylonitrile; halogen-containing vinyl monomers typified by vinyl chloride; and nitro vinyl monomers typified by nitrostyrene.

[0050] For the purpose of adjusting the acid value of the resin, it is preferable to use a copolymer of a styrene-based monomer, an unsaturated carboxylic acid ester, and a vinyl-based monomer containing an unsaturated carboxylic acid. Furthermore, for the purpose of adjusting the molecular weight, among the vinyl-based monomers mentioned above, a monomer having multiple vinyl groups, such as divinylbenzene or 1,6-hexanediol diacrylate, can be used as a crosslinking agent.

[0051] The glass transition temperature of the carboxyl group-containing resin is preferably 30° C. to 110° C., and more preferably 50° C. to 90° C. The peak molecular weight (Mp) of the carboxyl group-containing resin is preferably 3,000 to 50,000, and more preferably 5,000 to 20,000.

[0052] <Metal ions and ammonium ions A n+ (cation) In the present invention, examples of the cation that forms a salt with a carboxy group include conventionally known metal ions and ammonium ions. Among these, metal ions are preferred. Specifically, Li + , Na + , K. + , Ag +Monovalent metal ions such as Mg 2+ , Ca 2+ , Zn 2+ , Fe 2+ Divalent metal ions such as Al 3+ , Fe 3+ Among them, divalent or higher valent metal ions are preferred because they are difficult to remove using conventional cleaning methods and are more likely to be removed using fine bubbles.

[0053] These cations are preferably present in an ionic state in the aqueous medium and are immobilized on the surface of the resin particles by forming an ionic bond with a carboxy group present on the surface of the resin particles.

[0054] <Relationship between the mass of resin particles P and the mass of cleaning liquid W> The ratio P / W, where P is the mass of the resin particles in the cleaning process and W is the mass of the cleaning solution used in the cleaning process, is preferably 0.1 or more and 1.0 or less. The P / W value represents the efficiency of cleaning, and a higher value indicates a lower environmental impact and more efficient cleaning.

[0055] <Relationship between the mass of cations, M, and the mass of cleaning solution, W> The ratio M / W of the mass of metal ions or ammonium ions in the resin particles in the washing process to the mass W of the washing solution used in the washing process is 5.0 x 10 -6 It is preferable that the above relationship is satisfied. By satisfying the above relationship, clogging due to the reprecipitation of cations as salts in the filter paper or filter cloth can be suppressed. Therefore, even when the cleaning step is performed continuously, the filtration efficiency does not decrease, and the cleaning step can be performed efficiently.

[0056] <Relationship between the mass of cations before the washing process, M1, and the mass of cations after the washing process, M2> When the mass of the metal ions or ammonium ions in the resin particles before the washing process is M1 and the mass of the metal ions or ammonium ions in the resin particles after the washing process is M2, the reduction rate of the mass of the metal ions or ammonium ions (M1-M2) / M1 is preferably 0.50 or more. This reduction rate relationship indicates that the amount of salt present on the toner surface has been reduced sufficiently to improve the charging performance in a high-humidity environment.

[0057] Next, other materials that can be used for the resin particles will be described in detail below.

[0058] <Other resins> The resin particles of the present invention may contain other resins in addition to the carboxyl group-containing resin described above. The other resins can be used as binder resins when toner is obtained via the resin particles.

[0059] As the other resin, any conventionally known resin can be used without any particular limitation. Specific examples include polyester resin, vinyl resin, polyurethane resin, polyamide resin, etc. Among these, vinyl resin is preferably used.

[0060] When other resins are used as binder resins, the glass transition temperature is preferably 30 to 90° C., and more preferably 40 to 80° C. The peak molecular weight (Mp) is preferably 3,000 to 50,000, and more preferably 5,000 to 40,000.

[0061] <Release agents / plasticizers> The resin particles of the present invention preferably contain a release agent and / or a plasticizer. The materials listed below can be used as either a release agent or a plasticizer depending on the resin used at the same time. When selecting a material, an appropriate one can be selected taking into consideration factors such as compatibility with the resin. Specifically, materials with low compatibility with the resin are preferably used as release agents that separate from the resin during the fixing process and exhibit releasability from the fixing member, thereby enabling good separation from the fixing member. In contrast, materials with high compatibility with the resin are preferably used as plasticizers that dissolve in the resin during the fixing process, thereby reducing viscosity and enabling fixing at lower temperatures.

[0062] As the release agent and / or plasticizer, known waxes, silicone oils, etc. can be used without any particular limitation, and among these, it is preferable to use waxes.

[0063] Specifically, petroleum-based hydrocarbon waxes such as paraffin wax, microcrystalline wax, and petrolatum and derivatives thereof, montan wax and derivatives thereof, and hydrocarbon waxes and derivatives thereof produced by the Fischer-Tropsch process, monofunctional ester waxes, such as behenyl behenate, stearyl stearate, behenyl stearate, and palmityl palmitate, typified by esters of monohydric alcohols and aliphatic carboxylic acids, or esters of monohydric carboxylic acids and aliphatic alcohols; bifunctional ester waxes, such as esters of dihydric alcohols and aliphatic carboxylic acids, or esters of dihydric carboxylic acids and aliphatic alcohols, such as ethylene glycol distearate, dibehenyl sebacate, and hexanediol dibehenate; trifunctional ester waxes, such as esters of trihydric alcohols and aliphatic carboxylic acids, or esters of trihydric carboxylic acids and aliphatic alcohols, such as glycerin tribehenate; tetrafunctional ester waxes, such as esters of tetrahydric alcohols and aliphatic carboxylic acids, or esters of tetrahydric carboxylic acids and aliphatic alcohols, such as pentaerythritol tetrastearate and pentaerythritol tetrapalmitate; hexafunctional ester waxes, such as esters of hexahydric alcohols and aliphatic carboxylic acids, or esters of hexahydric carboxylic acids and aliphatic alcohols, such as dipentaerythritol hexastearate and dipentaerythritol hexapalmitate; Esters of polyhydric alcohols and aliphatic carboxylic acids, such as polyglycerol behenate, or esters of polyhydric carboxylic acids and aliphatic alcohols; Natural ester waxes such as carnauba wax and rice wax; Ester waxes such as Examples include polyolefin hydrocarbon waxes such as polyethylene and polypropylene and their derivatives, natural waxes such as carnauba wax and candelilla wax and their derivatives. Derivatives also include oxides, block copolymers with vinyl monomers, and graft modified products.

[0064] Other examples include alcohols such as higher aliphatic alcohols, fatty acids such as stearic acid and palmitic acid or their acid amides, esters, and ketones, hydrogenated castor oil and its derivatives, vegetable waxes, and animal waxes.These may be used alone or in combination.

[0065] Among these, hydrocarbon waxes and ester waxes are preferred. Generally, hydrocarbon waxes tend to have low compatibility with resins, and therefore can be preferably used as release agents. On the other hand, ester waxes tend to have high compatibility with resins, and therefore can be preferably used as plasticizers. As the ester wax, monofunctional ester waxes or bifunctional ester waxes are more preferred. Among these, at least one compound selected from the group consisting of compounds represented by the following formula (4), compounds represented by formula (5), and compounds represented by formula (6) is even more preferred.

[0066] [ka] (In formula (4), formula (5) and formula (6), R 31 and R 41 each independently represents an alkylene group having 2 to 8 carbon atoms, and R 32 , R 33 , R 42 , R 43 , R 51 and R 52 each independently represents a linear alkyl group having 14 to 24 carbon atoms (preferably 16 to 24).

[0067] In the analysis of toner particles by time-of-flight secondary ion mass spectrometry, the presence ratio of ester wax C W (%) is preferably 10% or less, more preferably 0% or more and 5% or less, even more preferably 0% or more and 3% or less, even more preferably 0% or more and 1% or less, and particularly preferably 0%. W The fact that C is in the above range indicates that the amount of ester wax on the surface of the toner is small. W When the surface roughness is in the above range, the adhesion of the toner to the drum is reduced, and the transferability is improved.

[0068] The content of the release agent and / or plasticizer is preferably 1.0 part by mass or more and 50.0 parts by mass or less when the total of the carboxyl group-containing resin and other resins is 100.0 parts by mass.

[0069] The melting point of the release agent and / or plasticizer is preferably 60°C or higher and 120°C or lower, more preferably 60°C or higher and 100°C or lower, and even more preferably 60°C or higher and 80°C or lower.

[0070] <Coloring agent> The resin particles of the present invention may contain a colorant. As the colorant, there are no particular limitations and conventionally known pigments and dyes of black, yellow, magenta, cyan, and other colors, magnetic materials, and the like can be used.

[0071] Examples of black colorants include black pigments such as carbon black.

[0072] Examples of yellow colorants include yellow pigments and dyes such as monoazo compounds, disazo compounds, condensed azo compounds, isoindolinone compounds, benzimidazolone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and allylamide compounds. Specific examples include CI Pigment Yellow 74, 93, 95, 109, 111, 128, 155, 174, 180, and 185, and CI Solvent Yellow 162.

[0073] Examples of magenta colorants include magenta pigments and dyes such as monoazo compounds, condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinone compounds, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds. Specific examples include CI Pigment Red 2, 3, 5, 6, 7, 23, 48:2, 48:3, 48:4, 57:1, 81:1, 122, 144, 146, 150, 166, 169, 177, 184, 185, 202, 206, 220, 221, 238, 254, 269, and CI Pigment Violet 19.

[0074] Examples of cyan colorants include cyan pigments and cyan dyes such as copper phthalocyanine compounds and their derivatives, anthraquinone compounds, and basic dye lake compounds. Specific examples include CI Pigment Blue 1, 7, 15, 15:1, 15:2, 15:3, 15:4, 60, 62, and 66.

[0075] The content of the colorant is preferably 1.0 part by mass or more and 20.0 parts by mass or less when the total of the carboxyl group-containing resin and other resins is 100.0 parts by mass.

[0076] The toner may also contain a magnetic material to form a magnetic toner, in which case the magnetic material may also serve as a colorant.

[0077] Examples of magnetic materials include iron oxides such as magnetite, hematite, and ferrite; metals such as iron, cobalt, and nickel; and alloys of these metals with metals such as aluminum, cobalt, copper, lead, magnesium, tin, zinc, antimony, beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, and vanadium, and mixtures thereof.

[0078] When a magnetic material is used as a colorant, the content of the magnetic material is preferably 20.0 parts by mass or more and 120.0 parts by mass or less when the total of the carboxyl group-containing resin and other resins is 100.0 parts by mass.

[0079] <Charge control agent> The resin particles of the present invention may contain a charge control agent. As the charge control agent, any known charge control agent can be used without any particular limitation.

[0080] Specific examples of the negative charge control agent include metal compounds of aromatic carboxylic acids such as salicylic acid, alkylsalicylic acid, dialkylsalicylic acid, naphthoic acid, and dicarboxylic acids, or polymers or copolymers having metal compounds of the aromatic carboxylic acids; polymers or copolymers having sulfonic acid groups, sulfonate salt groups, or sulfonate ester groups; metal salts or metal complexes of azo dyes or azo pigments; boron compounds, silicon compounds, and calixarenes.

[0081] On the other hand, examples of positive charge control agents include quaternary ammonium salts, polymeric compounds having quaternary ammonium salts in the side chains, guanidine compounds, nigrosine compounds, imidazole compounds, etc. As polymers or copolymers having a sulfonate group or a sulfonate ester group, homopolymers of sulfonic acid group-containing vinyl monomers such as styrene sulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 2-methacrylamido-2-methylpropanesulfonic acid, vinyl sulfonic acid, and methacrylic sulfonic acid, or copolymers of the vinyl monomers listed in the section on carboxyl group-containing resins with the above-mentioned sulfonic acid group-containing vinyl monomers can be used.

[0082] The content of the charge control agent is preferably 0.01 parts by mass or more and 5.0 parts by mass or less when the total of the carboxyl group-containing resin and other resins is 100.0 parts by mass.

[0083] <Physical properties of resin particles> The acid value of the resin particle surface is preferably 0.02 mgKOH / g or more and 1.00 mgKOH / g or less. When the acid value of the resin particle surface is within the above range, the charge amount of the resulting toner tends to fall within a suitable range. The acid value of the resin particle surface is more preferably 0.05 mgKOH / g or more and 0.50 mgKOH / g or less, and even more preferably 0.05 mgKOH / g or more and 0.30 mgKOH / g or less.

[0084] The average circularity of the resin particles is preferably 0.960 or more. When the average circularity of the resin particles is within the above range, the surface of the resin particles can be easily cleaned uniformly. In addition, the adhesion to the drum is reduced, thereby improving transferability. The average circularity of the resin particles is more preferably 0.980 or more.

[0085] <Method of manufacturing resin particles> The resin particles used in the washing step of the present invention are not particularly limited, and can be produced by wet production methods such as suspension polymerization, emulsion aggregation, and dissolution suspension, or dry production methods such as pulverization. Among these, wet production methods are preferred because they facilitate the placement of carboxyl group-containing resins that improve chargeability on the resin particle surfaces, and also because release agents and plasticizers are less likely to be exposed, making it easier to obtain toners with excellent chargeability and durability. Among these, suspension polymerization and emulsion aggregation methods are more preferred.

[0086] The steps for producing resin particles by suspension polymerization and the raw materials used in this production method will be described in detail below, but the present invention is not limited to this example.

[0087] [Manufacturing process] (Dispersion process) The dispersion step is a step of dispersing the colorant in the presence of a polymerizable monomer to obtain a colorant dispersion. A conventional media-type or non-media-type disperser can be used as a dispersing device in the dispersion step. Furthermore, a carboxyl group-containing resin, a charge control agent, and other raw materials may be added in the dispersion step.

[0088] (Mixing process) The mixing step is a step of mixing a polymerizable monomer, a colorant, a release agent, a carboxyl group-containing resin, and other raw materials to obtain a polymerizable monomer composition. The colorant dispersion obtained in the dispersion step described above may be used as the polymerizable monomer and colorant. Furthermore, in addition to the colorant dispersion, a carboxyl group-containing resin, a polymerizable monomer, and a colorant may be further added. In the mixing step, a polymerization initiator and a charge control agent may also be added.

[0089] (granulation process) The granulation step is a step of forming particles of a polymerizable monomer composition in an aqueous medium to obtain a suspension. The method of particle formation is not particularly limited, but for example, a device capable of strong stirring, such as an (in-line type) emulsifying disperser (manufactured by Pacific Machinery Works, trade name "Milder") or a high-speed emulsifying disperser (manufactured by Primix Corporation, trade name "Homomixer"), can be used. In addition, it is preferable that the aqueous medium contains a dispersion stabilizer. In the granulation step, a polymerization initiator may also be added.

[0090] (Polymerization process) The polymerization step is a step of polymerizing the polymerizable monomer contained in the particles of the polymerizable monomer composition in the suspension to form a resin. The resin formed through the polymerization step may be a carboxy group-containing resin.

[0091] (Distillation process) The distillation step is a step of removing unreacted polymerizable monomers. As the distillation method, known methods such as atmospheric distillation, reduced pressure distillation, and steam distillation can be used.

[0092] (Dispersant removal process) The dispersant removal step is a step of removing a dispersion stabilizer. For example, when an inorganic dispersant is used, it is preferable to remove the dispersion stabilizer by performing a treatment using a known acid, base, or the like under conditions in which the inorganic dispersant is dissolved.

[0093] (filtration process) The filtration step is a step of filtering resin particles dispersed in an aqueous medium to separate them into solid and liquid. The washing step may be performed after or before the filtration step, but it is preferable to perform the washing step on the washed cake formed by the filtration step.

[0094] If the resin particles are obtained in the form of a cake containing moisture after the filtration step, it is preferable to carry out a drying step described below. When the drying step described below is carried out, it is preferable to carry out a crushing step of crushing the cake into pieces of several mm to several cm square after the filtration step in order to carry out the drying step efficiently.

[0095] [raw materials] <Polymerizable monomer> As the polymerizable monomer used in the suspension polymerization method, any conventionally known polymerizable monomer can be used without any particular limitation. Among them, the vinyl-based monomers listed in the section on vinyl-based resins in the description of the carboxyl group-containing resin can be preferably used.

[0096] <Polymerization initiator> The polymerization initiator used in the suspension polymerization method is not particularly limited and may be any conventionally known polymerization initiator. Specifically, hydrogen peroxide, acetyl peroxide, cumyl peroxide, tert-butyl peroxide, propionyl peroxide, benzoyl peroxide, chlorobenzoyl peroxide, dichlorobenzoyl peroxide, bromomethylbenzoyl peroxide, lauroyl peroxide, ammonium persulfate, sodium persulfate, potassium persulfate, diisopropyl peroxycarbonate, tetralin hydroperoxide, 1-phenyl-2-methylpropyl-1-hydroperoxide, pertriphenylacetic acid tert-hydroperoxide, tert-butyl performate, tert-butyl peracetate, tert-butyl perbenzoate, tert-butyl perphenylacetic acid, tert-butyl permethoxyacetate, and per-N-(3-toluyl)palmitic acid tert-butylbenzoyl peroxide. Examples of the polymerization initiator include peroxide-based polymerization initiators such as t-butyl peroxy 2-ethylhexanoate, t-butyl peroxypivalate, t-butyl peroxyisobutyrate, t-butyl peroxyneodecanoate, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, and lauroyl peroxide; and azo- or diazo-based polymerization initiators such as 2,2'-azobis-(2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,1'-azobis(cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, and azobisisobutyronitrile. Among these, it is preferable to use a peroxide-based polymerization initiator.

[0097] The polymerization initiator is preferably used in an amount of 1.0 part by mass or more and 20.0 parts by mass or less per 100.0 parts by mass of the polymerizable monomer.

[0098] <Dispersion stabilizer> The dispersion stabilizer used in the suspension polymerization method is not particularly limited and may be any conventionally known dispersion stabilizer. Specific examples include the following: poorly water-soluble phosphates, such as tricalcium phosphate, hydroxyapatite, magnesium phosphate, zinc phosphate, and aluminum phosphate; other inorganic dispersion stabilizers, such as calcium carbonate, magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate, bentonite, silica, and alumina; organic dispersion stabilizers, such as polyvinyl alcohol, gelatin, methyl cellulose, methylhydroxypropyl cellulose, ethyl cellulose, sodium salt of carboxymethyl cellulose, and starch; anionic surfactants, such as alkyl sulfate ester salts, alkylbenzene sulfonates, and fatty acid salts; nonionic surfactants, such as polyoxyethylene alkyl ethers and polyoxypropylene alkyl ethers; and cationic surfactants, such as alkylamine salts and quaternary ammonium salts. Among these, poorly water-soluble phosphates are preferred because of their high dispersion stabilizing effect and ease of removal. Among these, it is more preferable to use calcium-containing phosphates such as tricalcium phosphate and hydroxyapatite, because it is easy to control the zeta potential and the affinity with fine bubbles.

[0099] The dispersion stabilizer is preferably used in an amount of 0.5 parts by mass or more and 5.0 parts by mass or less per 100.0 parts by mass of the polymerizable monomer.

[0100] The resin particles obtained through the above steps are subjected to the washing step of the present invention.

[0101] [Toner manufacturing method] The toner production method of the present invention includes a washing step of washing the resin particles with a washing liquid. The toner production method of the present invention will be described in detail below.

[0102] <Cleaning process> The washing step of the present invention is not particularly limited and may be a conventionally known washing step. Specific examples include the following filtration washing step in which a washing liquid is passed through a washed cake formed from resin particles to wash the resin particles, and a step in which resin particles are dispersed in a washing liquid and washed. Among these, a filtration washing step is preferred because it enables uniform and efficient washing with a small amount of washing liquid. When a washing liquid is passed through the washed cake in the filtration washing step, the washing efficiency can be further improved by applying pressure to the upper part of the washed cake or reducing the pressure below the washed cake. Furthermore, a continuous filtration washing step in which washing is performed continuously while the washed cake is being transferred is preferred because this enables continuous treatment.

[0103] Examples of filtration equipment that can be used in the continuous filtration and washing process include drum filters (manufactured by Mitsubishi Chemical Engineering Co., Ltd.), blowback filters (manufactured by Mitsubishi Chemical Engineering Co., Ltd.), Eagle filters (manufactured by Sumitomo Heavy Industries Environment Co., Ltd.), vacuum horizontal belt filters (manufactured by Hitachi Zosen Corporation), horizontal belt filters (manufactured by Tsukishima Kikai Co., Ltd.), and OS filters (manufactured by Japan Chemical Engineering Co., Ltd.).

[0104] <Each process after the cleaning process> After the washing step, it is preferable to obtain the toner by carrying out the following steps.

[0105] (drying process) The drying step is a step of removing moisture contained in the washed cake obtained in the filtration step. A conventionally known drying method can be used in the drying step of the present invention without any particular limitations. Specific examples include vacuum drying, fluidized bed drying, and airflow drying. Among these, a loop airflow dryer is preferred because it can uniformly apply heat using a drying gas and effectively separate dried toner particles from undried toner particles. Examples of loop airflow dryers include a flash jet dryer (manufactured by Seishin Enterprise Co., Ltd.) and a jet turbo dryer (manufactured by Hiraiwa Iron Works Co., Ltd.).

[0106] (Classification process) The classification step is a step of removing small and / or large particles from the resin particles to obtain toner particles. The classification step may be carried out depending on the particle size and particle size distribution of the obtained resin particles.

[0107] (External addition process) The external addition step is a step of obtaining a toner by mixing the obtained toner particles with an external additive and attaching the external additive to the surface of the toner particles to impart properties such as fluidity and chargeability. The external addition step may be performed depending on the required toner properties. If the external addition step is not performed, the toner particles obtained in the drying step or classification step can be used as a toner as is.

[0108] The mixer for externally adding the external additive to the toner particles is not particularly limited, and any known mixer, whether dry or wet, can be used. Examples include FM Mixer (manufactured by Nippon Coke & Engineering Co., Ltd.), Super Mixer (manufactured by Kawata Corporation), Nobilta (manufactured by Hosokawa Micron Corporation), and Hybridizer (manufactured by Nara Kikai Co., Ltd.). To control the coating state of the external additive, the toner can be prepared by adjusting the rotation speed, processing time, and water temperature and amount in the jacket of the external addition device.

[0109] In addition, examples of sieving devices used to sift out coarse particles after external addition include Ultrasonic (manufactured by Koei Sangyo Co., Ltd.); Resonaseave, Gyrosifter (Tokuju Kogyo Co., Ltd.); Vibrasonic System (manufactured by Dalton Co., Ltd.); Soniclean (manufactured by Shinto Kogyo Co., Ltd.); Turbo Screener (manufactured by Turbo Kogyo Co., Ltd.); and Microsifter (manufactured by Makino Sangyo Co., Ltd.).

[0110] The external additive used in the external addition step is not particularly limited and any conventionally known external additive can be used.

[0111] Specific examples include the following: raw silica microparticles, such as wet-process silica and dry-process silica; surface-treated silica microparticles obtained by surface-treating raw silica microparticles with a treating agent such as a silane coupling agent, a titanium coupling agent, silicone oil, or fatty acid; metal oxide microparticles, such as titanium oxide microparticles, aluminum oxide microparticles, zinc oxide microparticles, and cerium oxide; surface-treated metal oxide microparticles obtained by surface-treating metal oxide microparticles with a treating agent such as a silane coupling agent, a titanium coupling agent, silicone oil, or fatty acid; complex oxide microparticles, such as strontium titanate microparticles; surface-treated complex oxide microparticles obtained by surface-treating complex oxide microparticles with a treating agent such as a silane coupling agent, a titanium coupling agent, silicone oil, or fatty acid; fatty acid metal salts, such as zinc stearate and calcium stearate; clay minerals, such as hydrotalcite; and resin microparticles, such as vinylidene fluoride microparticles and polytetrafluoroethylene microparticles.

[0112] The content of the external additive is preferably 0.1 parts by mass or more and 10.0 parts by mass or less with respect to 100.0 parts by mass of the toner particles.

[0113] [Methods for measuring physical properties] The methods for measuring the physical properties of the resin particles, the toner, and each material will be described below.

[0114] <Isolation of resin particles> Before the washing process, 10% HCl is added to the resin particle dispersion to adjust the pH to 2.0. The solids are then filtered and washed three times with the same amount of ion-exchanged water as the resin particle dispersion. The water is then removed by drying in a vacuum dryer at 40°C for 24 hours to obtain resin particles.

[0115] <-(COO - ) n A n+ Detection of X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (TOF-SIMS) were used to analyze the -(COO) - ) n A n+ is detected by the following method.

[0116] The presence of metal elements or ammonium ions on the surface of the resin particles is confirmed by measuring the resin particles under the following conditions. Measurement equipment: X-ray photoelectron spectrometer: Quantum2000 (ULVAC-PHI, Inc.) X-ray source: Monochrome Al Kα ·Xray Setting:100μmφ(25W(15KV)) Photoelectron take-off angle: 45 degrees Neutralization Condition: Use the Neutralization Gun and Ion Gun together ·Analysis area: 300×200μm Pass Energy: 58.70 eV Step size: 0.1.25 eV Analysis software: Maltipak (PHI)

[0117] Next, we will explain how to determine the quantitative value of a metal element by analysis, using Ca as an example. First, the peak derived from the C-C bond in the carbon 1s orbital is corrected to 285 eV. Then, from the peak shifts at positions corresponding to each Ca orbital (2s orbital: 440 eV, 2p1 / 2 orbital: 351 eV, 2p3 / 2 orbital: 347 eV, etc.), we can confirm that a salt has been formed with a carboxy group.

[0118] In the case of ammonium ions, the following TOF-SIMS analysis is performed.

[0119] The resin particle sample is analyzed using TOF-SIMS (TRIFTIV: manufactured by ULVAC-PHI, Inc.) under the following conditions. Primary ion species: gold ions (Au + ) Primary ion current: 2pA ·Analysis area: 300×300μm 2 - Number of pixels: 256 x 256 ·Analysis time: 3min Repetition rate: 8.2kHz Charge Neutralization: ON Secondary ion polarity: Positive Secondary ion mass range: m / z 0.5~1850 Sample substrate: Indium

[0120] When analysis is performed under the above conditions, if a peak derived from ammonium ions (m / z: 18) is detected, it is determined that ammonium ions are present on the surface of the resin particles.

[0121] <Measurement of the acid value on the surface of resin particles> The acid value of the resin particle surface is measured by the following neutralization titration method.

[0122] 10.0 g of resin particles are dispersed in 100 mL of a 5.0 wt % aqueous solution of the nonionic surfactant Contaminon N (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.).

[0123] The resulting dispersion is titrated with a 0.1 mol / L KOH ethanol solution. The point at which the pH reaches 9.0 is used as the endpoint, and the acid value (mgKOH / g) of the resin particle surface is calculated from the amount of KOH ethanol solution used.

[0124] <Measurement of resin acid value> The acid value is the number of milligrams of potassium hydroxide required to neutralize the acid contained in 1 g of sample. The acid value of the binder resin is measured in accordance with JIS K 0070-1992. Specifically, it is measured according to the following procedure.

[0125] (1) Preparation of reagents Dissolve 1.0 g of phenolphthalein in 90 ml of ethyl alcohol (95 vol%) and add ion-exchanged water to make 100 ml to obtain a phenolphthalein solution. Dissolve 7 g of special-grade potassium hydroxide in 5 ml of water and add ethyl alcohol (95 vol%) to make 1 L. Place the solution in an alkali-resistant container to avoid contact with carbon dioxide and leave it for 3 days, then filter to obtain a potassium hydroxide solution. Store the resulting potassium hydroxide solution in an alkali-resistant container. The factor of the potassium hydroxide solution is determined by placing 25 ml of 0.1 mol / L hydrochloric acid in an Erlenmeyer flask, adding a few drops of the phenolphthalein solution, and titrating with the potassium hydroxide solution to determine the amount of potassium hydroxide solution required for neutralization. The 0.1 mol / L hydrochloric acid used is prepared in accordance with JIS K 8001-1998.

[0126] (2) Operation (A) Main test 2.0 g of crushed amorphous resin and crystalline resin samples were weighed into a 200 ml Erlenmeyer flask, and 100 ml of a 2:1 toluene / ethanol mixture was added and allowed to dissolve for 5 hours. A few drops of the phenolphthalein solution were then added as an indicator, and the solution was titrated with the potassium hydroxide solution. The titration endpoint was determined when the indicator's light red color persisted for approximately 30 seconds.

[0127] (B) Blank test The titration is carried out in the same manner as above, except that no sample is used (i.e., only the toluene / ethanol (2:1) mixed solution is used).

[0128] (3) The obtained results are substituted into the following formula to calculate the acid value. A=[(CB)×f×5.61] / S where A is the acid value (mgKOH / g), B is the amount of potassium hydroxide solution added for the blank test (ml), C is the amount of potassium hydroxide solution added for the main test (ml), f is the factor of the potassium hydroxide solution, and S is the sample (g).

[0129] <Mass of metal ion or ammonium ion M> The mass of metal ions or ammonium ions in the resin particles is measured using the wavelength dispersive X-ray fluorescence analyzer "Axios" (PANalytical) and the accompanying dedicated software "SuperQ ver. 4.0F" (PANalytical) for setting measurement conditions and analyzing measurement data, according to the following method.

[0130] An example will be given in which Ca is used as the metal, but the same procedure can be carried out for other metals.

[0131] Rh is used as the anode of the X-ray tube, the measurement atmosphere is vacuum, the measurement diameter (collimator mask diameter) is 27 mm, and the measurement time is 10 seconds.

[0132] Furthermore, when measuring light elements, a proportional counter (PC) is used, and when measuring heavy elements, a scintillation counter (SC) is used.

[0133] The measurement sample was prepared by placing 4 g of resin particles in a special aluminum ring for pressing, flattening it, and then pressing it at 20 MPa for 60 seconds using a tablet molding compression machine "BRE-32" (manufactured by Maekawa Testing Machinery Manufacturing Co., Ltd.) to form a pellet with a thickness of 2 mm and a diameter of 39 mm.

[0134] Calcium chloride (CaCl2) fine powder is added to polystyrene particles (Techpolymer SBX-8: manufactured by Sekisui Plastics Co., Ltd.) so that the amount is 0.01% by mass of the total resin particles, and the mixture is thoroughly mixed using a coffee mill.

[0135] Similarly, calcium chloride fine powder is mixed with polystyrene particles at concentrations of 0.05 mass%, 0.1 mass%, 0.5 mass%, 1.0 mass%, 5.0 mass%, 10.0 mass%, and 20.0 mass%, respectively, and these are used as samples for the calibration curve.

[0136] For each sample, a pellet of the sample for the calibration curve is prepared as described above using a tablet press, and the count rate (unit: cps) of the Si-Kα ray observed at a diffraction angle (2θ) of 109.08° when pentaerythritol (PET) is used as the spectroscopic crystal is measured.

[0137] In this case, the acceleration voltage and current value of the X-ray generator are set to 24 kV and 100 mA, respectively.

[0138] A linear calibration curve is obtained by plotting the count rate of the obtained X-rays on the vertical axis and the amount of SiO2 added in each calibration sample on the horizontal axis.

[0139] Next, the resin particles to be analyzed are pelletized as described above using a tablet press, and the counting rate of the Si-Kα ray is measured. The calcium element content (mol) in the toner is then determined from the calibration curve. The resulting content is converted to mass, and the mass M of the metal ion or ammonium ion is used.

[0140] <Method for measuring average circularity> The average circularity of the resin particles is measured and analyzed using a flow particle image analyzer "FPIA-3000" (manufactured by Sysmex Corporation) under the following conditions.

[0141] The specific measurement method is as follows. First, 20 ml of ion-exchanged water, from which impurities such as solids have been removed, is placed in a glass container. 0.2 ml of a solution prepared by diluting "Contaminon N" (a 10% by weight aqueous solution of a pH 7 neutral detergent for cleaning precision measuring instruments, consisting of a nonionic surfactant, an anionic surfactant, and an organic builder, manufactured by Wako Pure Chemical Industries, Ltd.) three times by weight with ion-exchanged water is added as a dispersant. 0.02 g of the measurement sample is then added, and the mixture is dispersed for 2 minutes using an ultrasonic disperser to obtain a dispersion for measurement. The dispersion is then cooled appropriately so that its temperature is between 10°C and 40°C. A tabletop ultrasonic cleaner disperser with an oscillation frequency of 50 kHz and an electrical output of 150 W (e.g., "VS-150" manufactured by Vervoclear) is used as the ultrasonic disperser. A predetermined amount of ion-exchanged water is placed in the water tank, and approximately 2 ml of the Contaminon N is added to the water tank.

[0142] For the measurements, the flow particle image analyzer described above equipped with an "UPlanApro" objective lens (10x magnification, 0.40 numerical aperture) was used, and the particle sheath "PSE-900A" (manufactured by Sysmex Corporation) was used as the sheath liquid. The dispersion prepared according to the above procedure was introduced into the flow particle image analyzer, and 3,000 toner particles were measured in HPF measurement mode and total count mode. The binarization threshold for particle analysis was set to 85%, and the analyzed particle diameters were limited to those with a circle-equivalent diameter of 1.985 μm or more and less than 39.69 μm, and the average circularity of the toner particles was determined.

[0143] Before starting the measurement, automatic focusing is performed using standard latex particles (for example, "RESEARCH AND TEST PARTICLES Latex Microsphere Suspensions 5200A" manufactured by Duke Scientific, diluted with ion-exchanged water).

[0144] <Identification of wax in toner> (1) Method for separating wax from toner First, the melting point of the wax in the toner was measured using a thermal analyzer (DSC Q2000, manufactured by TA Instruments Japan Co., Ltd.). 3.0 mg of toner was placed in a sample container in an aluminum pan (KIT No. 0219-0041), which was then placed on a holder unit and placed in an electric furnace. Under a nitrogen atmosphere, the sample was heated from 30°C to 200°C at a rate of 10°C / min. The DSC curve was measured using a differential scanning calorimeter (DSC), and the melting point of the wax in the toner sample was calculated.

[0145] Next, resin particles are dispersed in ethanol, a poor solvent for toner, and the temperature is raised to a temperature above the melting point of the wax. Pressure may be applied at this time if necessary. By this operation, the wax has exceeded its melting point and is melted and extracted into the ethanol. The wax can be separated from the toner by heating, and if pressure is applied, by performing solid-liquid separation while still under pressure. The extracted liquid is then dried and solidified to obtain the wax.

[0146] (2) Identification of wax by pyrolysis GCMS The specific conditions for identifying wax by pyrolysis GCMS are shown below. Mass spectrometer: ThermoFisherScinetific ISQ GC equipment: ThermoFisher Scientific FocusGC Ion source temperature: 250℃ Ionization method: EI Mass range: 50-1000 m / z Column: HP-5MS [30 m] Pyrolysis equipment: Japan Analytical Industry Co., Ltd. JPS-700 A small amount of the wax separated by extraction and 1 μL of tetramethylammonium hydroxide (TMAH) are added to a pyrofoil at 590°C. The resulting sample is subjected to pyrolysis GCMS measurement under the above conditions to obtain peaks derived from the wax. If the wax is an ester compound, peaks are obtained for the alcohol and carboxylic acid components. Due to the action of the methylating agent TMAH, the alcohol and carboxylic acid components are detected as methylated products. The molecular weight can also be obtained by analyzing the obtained peaks and identifying the wax structure. In the case of hydrocarbon waxes and other materials with a molecular weight distribution, the component that is most frequently detected is taken as the molecular weight of the wax.

[0147] <Method for measuring melting point> The melting point of the release agent or plasticizer is measured using a differential scanning calorimeter (DSC) Q2000 (manufactured by TA Instruments) under the following conditions. Heating rate: 10℃ / min Measurement start temperature: 20℃ Measurement end temperature: 180℃ The melting points of indium and zinc are used to correct the temperature of the detector, and the heat of fusion of indium is used to correct the amount of heat.

[0148] Specifically, 5 mg of sample is weighed out and placed in an aluminum pan, and a single measurement is performed. An empty aluminum pan is used as a reference. The peak temperature of the maximum endothermic peak at this time is taken as the melting point.

[0149] <Measurement of CW by time-of-flight secondary ion mass spectrometry of toner particles> To measure the ion amount (peak intensity) using TOF-SIMS, TRIFT-IV manufactured by ULVAC-PHI, Inc. is used.

[0150] The analysis conditions are as follows. Sample preparation: Adhering toner particles to an indium sheet Sample preparation: None Primary ions: Au ions Accelerating voltage: 30 kV Charge neutralization mode: On Measurement mode: Positive Raster: 300 μm Measurement time: 60 seconds From the spectrum obtained by measuring the ester wax standard, peaks specific to each material were selected, and the abundance ratio of the ester wax on the toner particle surface was calculated by comparing the peak intensity on the toner particle surface with the peak intensity of the standard.

[0151] <Method for measuring the glass transition temperature (Tg) of toner> The glass transition temperature (Tg) of the binder resin is measured in accordance with ASTM D3418-82 using a differential scanning calorimeter "Q1000" (manufactured by TA Instruments). The melting points of indium and zinc are used for temperature correction of the detector, and the heat of fusion of indium is used for heat quantity correction. Specifically, 5 mg of toner is precisely weighed and placed in an aluminum pan. An empty aluminum pan is used as a reference, and measurements are performed at a temperature rise rate of 1°C / min within a measurement range of 30 to 200°C. During this temperature rise, specific heat change is obtained in the temperature range of 40 to 100°C. The intersection of the line midway between the baselines before and after the specific heat change and the differential heat curve is taken as the glass transition temperature (Tg) of the toner.

[0152] <Method for measuring weight average particle size> The weight average particle diameter (D4) of resin particles, toner particles, or toner (hereinafter also referred to as toner, etc.) is calculated as follows.

[0153] The measuring device used is a precision particle size distribution measuring device using the narrow hole electrical resistance method, "Coulter Counter Multisizer 3" (registered trademark, manufactured by Beckman Coulter, Inc.), equipped with a 100 μm aperture tube.

[0154] Measurement conditions are set and measurement data is analyzed using the accompanying dedicated software "Beckman Coulter Multisizer 3 Version 3.51" (Beckman Coulter, Inc.). Measurements are performed using an effective number of 25,000 measurement channels.

[0155] The aqueous electrolyte solution used for the measurement is prepared by dissolving special grade sodium chloride in ion-exchanged water to a concentration of 1.0%, for example, "ISOTON II" (manufactured by Beckman Coulter, Inc.).

[0156] Before performing measurements and analysis, the dedicated software is set up as follows.

[0157] On the "Change Standard Measurement Method (SOMME)" screen of the dedicated software, set the total count in control mode to 50,000 particles, the number of measurements to 1, and the Kd value to the value obtained using "Standard Particles 10.0 μm" (Beckman Coulter, Inc.). Press the "Threshold / Noise Level Measurement Button" to automatically set the threshold and noise level. Also, set the current to 1,600 μA, the gain to 2, the electrolyte to ISOTON II, and check "Flush aperture tube after measurement."

[0158] On the "Pulse to particle size conversion setting" screen of the dedicated software, set the bin interval to logarithmic particle size, the particle size bin to 256 particle size bins, and the particle size range from 2 μm to 60 μm.

[0159] The specific measurement method is as follows. (1) Pour 200.0 mL of electrolyte solution into a 250 mL round-bottom glass beaker made specifically for the Multisizer 3, set it on the sample stand, and stir the stirrer rod counterclockwise at 24 revolutions per second. Then, use the "Aperture Tube Flush" function of the dedicated software to remove any dirt and air bubbles from inside the aperture tube. (2) 30.0 mL of the electrolyte solution is placed in a 100 mL flat-bottom glass beaker. 0.3 mL of a diluted solution of "Contaminon N" (a 10% aqueous solution of a pH 7 neutral detergent for cleaning precision measuring instruments, consisting of a nonionic surfactant, anionic surfactant, and organic builder, manufactured by Wako Pure Chemical Industries, Ltd.) diluted three times by mass with ion-exchanged water is added as a dispersant. (3) Prepare an ultrasonic disperser "Ultrasonic Dispersion System Tetra150" (manufactured by Nikkaki Bios Co., Ltd.) with an electrical output of 120 W and two built-in oscillators with an oscillation frequency of 50 kHz and a phase shift of 180 degrees. Place 3.3 L of ion-exchanged water in the ultrasonic disperser's water tank and add 2.0 mL of Contaminon N to this water tank. (4) Set the beaker (2) in the beaker fixing hole of the ultrasonic disperser, operate the ultrasonic disperser, and adjust the height of the beaker so that the resonance state of the liquid surface of the electrolytic solution in the beaker is maximized. (5) While the electrolyte solution in the beaker in (4) is being irradiated with ultrasonic waves, 10 mg of toner or the like is added little by little to the electrolyte solution and dispersed. The ultrasonic dispersion process is then continued for another 60 seconds. During the ultrasonic dispersion process, the water temperature in the water tank is appropriately adjusted to be between 10°C and 40°C. (6) Using a pipette, add the electrolytic solution (5) containing dispersed toner particles to the round-bottom beaker (1) placed in the sample stand, and adjust the measurement concentration to 5%. Then, measure the particle count until it reaches 50,000 particles. (7) The measurement data is analyzed using the dedicated software that comes with the device, and the weight-average particle size (D4) is calculated. Note that when the dedicated software is set to Graph / Volume %, the "Average diameter" on the "Analysis / Volume Statistics (Arithmetic Mean)" screen is the weight-average particle size (D4).

[0160] [Configurations included in the embodiments of the present invention] The disclosure of this embodiment includes the following configuration. (Configuration 1) A toner manufacturing method including a washing step of washing resin particles with a washing liquid, The resin particles have functional groups -(COO- ) n A n+ (In the formula, A n+ represents a metal ion or an ammonium ion, and n represents an integer of 1 or more and 3 or less, The cleaning solution contains fine bubbles, The number average particle size of the fine bubbles in the cleaning solution is 1.0 × 10 1 nm or more 1.0×10 5 nm or less, The method for producing a toner, wherein the zeta potential of the fine bubbles in the cleaning solution is -60 mV or more and 0 mV or less. (Configuration 2) The method for producing a toner according to Configuration 1, wherein the acid value of the resin particle surface is 0.02 mgKOH / g or more and 1.00 mgKOH / g or less. (Configuration 3) The number concentration of the fine bubbles in the cleaning solution is 1.0 × 10 4 3. The method for producing a toner according to claim 1, wherein the toner concentration is 1 / mL or more. (Configuration 4) The method for producing a toner according to any one of Configurations 1 to 3, wherein the zeta potential of the fine bubbles in the cleaning solution is −30 mV or more and −10 mV or less. (Configuration 5) The number average particle diameter of the fine bubbles in the cleaning solution is 1.0 × 10 1 nm or more 1.0×10 3 5. The method for producing a toner according to any one of configurations 1 to 4, wherein the toner has a thickness of 1 nm or less. (Configuration 6) The method for producing a toner according to any one of Configurations 1 to 5, wherein in the washing step, the resin particles are washed by passing the washing liquid through a cake to be washed that contains the resin particles. (Configuration 7) The method for producing a toner according to Configuration 6, wherein in the washing step, the cake to be washed is continuously washed while being transferred. (Configuration 8) The method for producing a toner according to any one of Configurations 1 to 7, wherein the ratio P / W of the mass P of the resin particles in the washing step to the mass W of the washing liquid used in the washing step is 0.1 or more and 1.0 or less. (Configuration 9) The ratio M / W of the mass M of the metal ions or ammonium ions in the resin particles in the washing step to the mass W of the washing solution used in the washing step is 5.0 × 10 -6 A method for producing a toner according to any one of the following configurations 1 to 8. (Configuration 10) The method for producing a toner according to any one of Configurations 1 to 9, wherein the resin particles have an average circularity of 0.960 or more. (Configuration 11) The method for producing a toner according to any one of Configurations 1 to 10, wherein, when the mass of the metal ions or ammonium ions before the washing step is M1 and the mass of the metal ions or ammonium ions after the washing step is M2, the reduction rate of the mass of the metal ions or ammonium ions (M1-M2) / M1 is 0.50 or more. [Example]

[0161] The present invention will be described in more detail with reference to the following examples, which, however, are not intended to limit the scope of the present invention. The toner and a method for producing the toner will be described below. Unless otherwise specified, "parts" and "%" in the examples and comparative examples are all based on mass.

[0162] <Example of producing fine bubble-containing water> [Fine bubble water 1] Deionized water containing dissolved air was prepared and passed through a fine bubble generator, the UP0290M 100V motor type (Shibata Co., Ltd.), to produce fine bubble-containing water 1. The number-average particle size and number concentration of the produced fine bubbles were 1.5 x 10 2 (nm), 1.7 × 10 6 (particles / mL) and the zeta potential was -22 mV. The physical properties of fine bubble-containing water 1 are shown in Table 1.

[0163] [Fine bubble water 2] Deionized water containing dissolved air was prepared, and a pipe equipped with a processing glass filter P100 (Shibata Scientific Co., Ltd.) with a pore size of 40 to 100 μm was placed inside the deionized water. Air was then introduced into the pipe at a pressure of 0.2 MPa to produce fine bubble-containing water 2. The number-average particle size and number concentration of the fine bubbles produced were 9.2 × 10 4 (nm), 1.3 × 10 5 (particles / mL) and the zeta potential was -22 mV. The physical properties of fine bubble-containing water 2 are shown in Table 1.

[0164] [Fine bubble-containing water 3, 4] Fine bubble-containing waters 3 and 4 were produced in the same manner as in the production example for fine bubble-containing water 2, except that the filter type and pore size were changed to those shown in Table 1. The physical properties of fine bubble-containing waters 3 and 4 are shown in Table 1.

[0165] [Fine bubble water 5] Fine bubble-containing water 5 was produced by diluting ultra-fine air bubble (nanobubble) water (manufactured by Nanox Co., Ltd.) 5,000 times with ion-exchanged water. The number-average particle size and number concentration of the produced fine bubbles were 5.5 × 10 1 (nm), 1.7 × 10 6 (particles / mL) and the zeta potential was -22 mV. The physical properties of fine bubble-containing water 5 are shown in Table 1.

[0166] [Fine bubble water 6] Fine bubble-containing water 6 was produced in the same manner as in the production example for fine bubble-containing water 1, except that ion-exchanged water in which oxygen was dissolved by bubbling oxygen gas was used instead of ion-exchanged water in which air was dissolved. The physical properties of fine bubble-containing water 6 are shown in Table 1.

[0167] [Fine bubble water 7] Fine bubble-containing water 7 was produced in the same manner as in the production example for fine bubble-containing water 1, except that ion-exchanged water in which nitrogen was dissolved by bubbling nitrogen gas was used instead of ion-exchanged water in which air was dissolved. The physical properties of fine bubble-containing water 7 are shown in Table 1.

[0168] [Fine bubble water 8] Fine bubble-containing water 8 was produced by adding a 10% HCl aqueous solution to fine bubble-containing water 7 to adjust the pH to 4.0. The physical properties of fine bubble-containing water 8 are shown in Table 1.

[0169] [Fine bubble water 9] Fine bubble-containing water 1 was diluted 150 times with ion-exchanged water to produce fine bubble-containing water 9. The physical properties of fine bubble-containing water 9 are shown in Table 1.

[0170] [Fine bubble water 10] Fine bubble-containing water 10 was produced by diluting fine bubble-containing water 1 350 times with ion-exchanged water. The physical properties of fine bubble-containing water 10 are shown in Table 1.

[0171] [Fine bubble water 11] Fine bubble-containing water 11 was produced in the same manner as in Production Example 2 of Fine Bubble-Containing Water 2, except that the dissolved gas and the introduced gas were changed from air to nitrogen, and a 10% aqueous HCl solution was added to adjust the pH to 4.0. The physical properties of the fine bubble-containing water are shown in Table 1.

[0172] [Fine bubble water 12] Fine bubble-containing water 12 was produced by adding a 10% HCl aqueous solution to fine bubble-containing water 11 to adjust the pH to 3.0. The physical properties of the fine bubble-containing water are shown in Table 1.

[0173] [Fine bubble water 13] Fine bubble-containing water 13 was produced in the same manner as in the production example for fine bubble-containing water 11, except that the filter pore size was changed to one shown in Table 1. The physical properties of fine bubble-containing water 13 are shown in Table 1.

[0174] [Table 1] *When the filter type item states "SPG filter," an SPG membrane filter (manufactured by SPG Techno Co., Ltd.) with the filter pore size shown in the table was used.

[0175] <Production example of resin particle dispersion> [Resin particle dispersion 1] (Production of aqueous media) 390.0 parts ion-exchanged water Sodium phosphate (12-hydrate) 14.0 parts The above materials were placed in a reaction vessel and kept at 60°C for 1.0 hour while purging with nitrogen.

[0176] A calcium chloride solution containing 9.2 parts of calcium chloride dihydrate dissolved in 10.0 parts of ion-exchanged water was added all at once to prepare an aqueous medium containing hydroxyapatite as a dispersion stabilizer using a homogenizer (Primix Corporation) while stirring at 12,000 rpm. The pH was adjusted to 6.0 with 1 mol / L of hydrochloric acid to obtain an aqueous medium.

[0177] (Production of polymerizable monomer composition) Polymerizable monomer: styrene 60.0 parts Colorant: CI Pigment Blue 15:3 6.5 parts The above materials were placed in an attritor (manufactured by Nippon Coke & Engineering Co., Ltd.), and further dispersed using zirconia particles having a diameter of 1.7 mm at 220 rpm for 5.0 hours to prepare a colorant dispersion in which the pigment was dispersed.

[0178] To the above colorant dispersion were added the following materials: Polymerizable monomer: styrene 20.0 parts Polymerizable monomer: n-butyl acrylate 20.0 parts Carboxylic group-containing resin: Polyester resin 5.0 parts (Condensate of bisphenol A propylene oxide 2 mole adduct / ethylene glycol / isosorbide / terephthalic acid / trimellitic acid, glass transition temperature Tg: 75°C, acid value: 5.0 mg KOH / g) Plasticizer: ethylene glycol distearate (melting point: 73°C) 9.0 parts Release agent: Fischer-Tropsch wax (melting point: 78°C) 5.0 parts

[0179] The above materials were kept at 65° C. and uniformly dissolved and dispersed using a homomixer at 500 rpm to prepare a polymerizable monomer composition.

[0180] (granulation process) While maintaining the temperature of the aqueous medium at 60°C and the rotation speed of the homomixer at 12,000 rpm, the polymerizable monomer composition was added to the aqueous medium, and 7.0 parts of t-butyl peroxypivalate as a polymerization initiator was added. Granulation was continued for 10 minutes while maintaining the rotation speed at 12,000 rpm.

[0181] (Polymerization process) The homogenizer was replaced with a mixer equipped with a propeller agitator, and the temperature was raised to 70°C over 30 minutes while stirring at 150 rpm. Polymerization was carried out for 4.0 hours while maintaining the temperature at 70°C, and the temperature was then raised to 85°C and heated for 0.5 hours to carry out the polymerization reaction. Then, 2°C cold water was added and the mixture was cooled to 30°C at a cooling rate of 4°C / sec. The mixture was then heated to 50°C while stirring at 150 rpm and maintained for 4.0 hours. The temperature was then lowered to 30°C, yielding a slurry in which resin particles were dispersed.

[0182] (Dispersant removal process) The resulting slurry was adjusted to pH 2.0 with 10% HCl aqueous solution and stirred at 150 rpm for 1 hour to dissolve the dispersant on the resin particle surfaces. Ion-exchanged water was added to adjust the resin particle concentration in the dispersion to 20.0%, yielding Resin Particle Dispersion 1 in which Resin Particles 1 were dispersed.

[0183] The weight average particle size (D4) of resin particles 1 was 6.7 μm, the acid value of the resin particle surface was 0.15 mg KOH / g, the average circularity was 0.985, and the glass transition temperature (Tg) was 56°C. In addition, calcium ions (Ca 2+ ) and -(COO - )2Ca 2+ The calcium ion content was 0.0030 mg per 1 g of resin particles. The physical properties of Resin Particle 1 are shown in Table 2.

[0184] [Resin particle dispersion 2] (Resin particle dispersion) Carboxylic acid-containing resin: 200 parts polyester resin (Condensate of bisphenol A propylene oxide 2 mole adduct / ethylene glycol / isosorbide / terephthalic acid / trimellitic acid, glass transition temperature Tg: 75°C, acid value: 5.0 mg KOH / g) 500 parts ion-exchanged water The above materials were placed in a stainless steel container, heated to 95°C in a hot bath, and melted. While thoroughly stirring at 7800 rpm using a homogenizer (IKA Ultra Turrax T50), 0.1 mol / L sodium bicarbonate was added to adjust the pH to above 7.0. A mixed solution of 3 parts sodium dodecylbenzenesulfonate and 297 parts ion-exchanged water was then gradually added dropwise to emulsify and disperse the mixture, yielding a resin particle dispersion. The solids concentration of the resin particle dispersion was 20%.

[0185] The particle size distribution of the resin microparticle dispersion was measured using a particle size measuring device (LA-960V2, manufactured by Horiba, Ltd.), and the number average particle size of the resin microparticles was 0.25 μm, and no coarse particles exceeding 1 μm were observed.

[0186] (Plasticizer particle dispersion) 500 parts ion-exchanged water Plasticizer (ethylene glycol distearate (melting point: 73°C)) 200 parts The above materials were placed in a stainless steel container, heated to 95°C in a hot bath, and melted. While thoroughly stirring at 7800 rpm using a homogenizer (IKA Ultra Turrax T50), 0.1 mol / L sodium bicarbonate was added to adjust the pH to greater than 7.0.

[0187] Thereafter, a mixed solution of 5 parts sodium dodecylbenzenesulfonate and 295 parts ion-exchanged water was gradually added dropwise to emulsify and disperse the mixture, yielding a plasticizer microparticle dispersion. The solids concentration of the plasticizer microparticle dispersion was 20%. The particle size distribution of the release agent microparticles contained in the plasticizer microparticle dispersion was measured using a particle size analyzer (HORIBA, Ltd., LA-960V2). The number-average particle size of the plasticizer microparticles contained was 0.35 μm, and no coarse particles exceeding 1 μm were observed.

[0188] (Colorant particle dispersion) Colorant: CI Pigment Blue 15:3 100 parts Sodium dodecylbenzenesulfonate 5 parts 400 parts ion-exchanged water The above ingredients were mixed and dispersed using a sand grinder mill to obtain a colorant particle dispersion. The solids concentration of the colorant particle dispersion was 20%. The particle size distribution of the colorant particles contained in this colorant particle dispersion was measured using a particle size analyzer (HORIBA, Ltd., LA-960V2). The number-average particle size of the colorant particles contained was 0.20 μm, and no coarse particles exceeding 1 μm were observed.

[0189] (Resin particle dispersion) ·Resin particle dispersion 500 parts 50 parts of colorant particle dispersion Plasticizer microparticle dispersion 50 parts Sodium dodecylbenzenesulfonate 5 parts The resin particle dispersion, plasticizer particle dispersion, and sodium dodecylbenzenesulfonate were charged into a reactor (1-liter flask, baffled anchor blade) and mixed uniformly. Meanwhile, the colorant particle dispersion was mixed uniformly in a 500-mL beaker, and this was gradually added to the reactor while stirring to obtain a mixed dispersion. While stirring the resulting mixed dispersion, 0.5 parts of aluminum sulfate aqueous solution (solid content) was added dropwise to form aggregated particles.

[0190] After the dropwise addition was completed, the system was purged with nitrogen, and the temperature was maintained at 50°C for 1 hour, and then at 55°C for 1 hour.

[0191] The temperature was then increased and maintained at 90°C for 30 minutes. The temperature was then decreased to 63°C and maintained for 3 hours to form fused particles. The reaction was carried out under a nitrogen atmosphere. After the specified time had elapsed, the temperature was decreased to 30°C at a rate of 4.0°C per minute. The temperature was then increased to 50°C while stirring at 150 rpm and maintained at this temperature for 4.0 hours. The temperature was then decreased to 30°C, and ion-exchanged water was added to adjust the solids concentration to 20%, yielding resin particle dispersion 2 in which resin particles 2 were dispersed.

[0192] The weight average particle size (D4) of resin particles 2 was 6.7 μm, the acid value of the resin particle surface was 0.15 mg KOH / g, the average circularity was 0.965, and the glass transition temperature (Tg) was 65° C. In addition, the metal ions were aluminum ions (Al 3+ ) and -(COO - )3Al 3+ It was confirmed that the resin particles had the following structure. The aluminum ion content per 1 g of resin particles was 0.0040 mg / g. The physical properties of resin particles 2 are shown in Table 2.

[0193] [Resin particle dispersion 3] Resin particle dispersion 3 was produced in the same manner as in Production Example of Resin Particle Dispersion 2, except that the polyester used in Production Example of Resin Particle Dispersion 2 was changed to the following. The physical properties of Resin Particle 3 are shown in Table 2. Polyester resin: condensation product of 2 moles of propylene oxide adduct of bisphenol A / ethylene glycol / isosorbide / terephthalic acid / trimellitic acid, glass transition temperature Tg: 75°C, acid value: 30.0 mg KOH / g

[0194] [Resin particle dispersion 4] Resin particle dispersion 4 was produced in the same manner as in Production Example of Resin Particle Dispersion 2, except that the polyester used in Production Example of Resin Particle Dispersion 2 was changed to the following. The physical properties of Resin Particle 4 are shown in Table 2. Polyester resin: condensation product of 2 moles of propylene oxide adduct of bisphenol A / ethylene glycol / isosorbide / terephthalic acid / trimellitic acid, glass transition temperature Tg: 75°C, acid value: 1.0 mgKOH / g

[0195] [Resin particle dispersion 5] Resin particle dispersion 5 was produced in the same manner as in Production Example of Resin Particle Dispersion 2, except that the polyester used in Production Example of Resin Particle Dispersion 2 was changed to the following. The physical properties of Resin Particle 5 are shown in Table 2. Polyester resin: condensation product of 2 moles of propylene oxide adduct of bisphenol A / ethylene glycol / isosorbide / terephthalic acid / trimellitic acid, glass transition temperature Tg: 75°C, acid value: 0.5 mg KOH / g

[0196] [Resin particle dispersion 6] Resin particle dispersion 6 was produced in the same manner as in Production Example of Resin Particle Dispersion 2, except that the temperature in the step of holding at 90°C for 30 minutes was changed to 70°C. The physical properties of Resin Particle 6 are shown in Table 2.

[0197] [Resin particle dispersion 7] Resin particle dispersion 7 was produced in the same manner as in Production Example of Resin Particle Dispersion 1, except that the polyester resin and plasticizer used in Production Example of Resin Particle Dispersion 1 were changed to those shown below. The physical properties of Resin Particle 7 are shown in Table 2. Polyester resin: condensation product of 2 moles of propylene oxide adduct of bisphenol A / terephthalic acid / trimellitic acid, glass transition temperature Tg: 70°C, acid value: 8.0 mg KOH / g Plasticizer: Behenyl stearate (melting point 68°C)

[0198] [Resin particle dispersion 8] Resin particle dispersion 8 was produced in the same manner as in Production Example of Resin Particle Dispersion 2, except that the amount of aluminum sulfate used was changed to 0.8 parts. The physical properties of Resin Particles 8 are shown in Table 2.

[0199] [Resin particle dispersion 9] Resin particle dispersion 9 was produced in the same manner as in Production Example of Resin Particle Dispersion 2, except that the amount of aluminum sulfate used was changed to 1.0 part in Production Example of Resin Particle Dispersion 2. The physical properties of Resin Particle 9 are shown in Table 2.

[0200] [Resin particle dispersion 10] Resin particle dispersion 10 was produced in the same manner as in Production Example of Resin Particle Dispersion 2, except that the polyester used was changed to the following. The physical properties of resin particles 10 are shown in Table 2. In this example, the terminal carboxyl groups of the polyester resin were capped with stearyl alcohol, so that -(COO - )3Al 3+ The structure of the compound was not confirmed (ion amount: 0.0000 mg / g). Polyester resin: condensation product of 2 moles of propylene oxide adduct of bisphenol A / ethylene glycol / isosorbide / terephthalic acid / trimellitic acid, terminal carboxyl groups capped with stearyl alcohol, glass transition temperature Tg: 75°C, acid value: 0.0 mgKOH / g

[0201] [Table 2]

[0202] <Toner manufacturing example> [Toner 1] (Cleaning process) A washing step was carried out under the following conditions using a vacuum horizontal belt filter (manufactured by Hitachi Zosen Corporation), which is a washing device that continuously washes the cake to be washed while transferring it, to obtain wet toner particles 1. Supply slurry: Resin particle dispersion 1 Cleaning solution: Fine bubble water 1 Cleaning solution temperature: 40℃ Slurry supply rate: 10 kg / h Cleaning fluid supply rate: 4kg / h Belt speed: Stop time / moving time = 10 / 1, average 0.2m / min Filter cloth: Polyester ·Vacuum degree: -70kPa

[0203] The ratio P / W between the mass of resin particles in the cleaning process and the mass of the cleaning solution is 0.50, and the ratio M / W between the mass of ions and the volume of the cleaning solution is 2.0 x 10 -6 Subsequently, the obtained wet cake was crushed to obtain wet toner particles 1.

[0204] After the above-mentioned cleaning process was carried out for 10 hours, a sample of the filter cloth was taken and observed under an optical microscope for clogging. The clogging was evaluated according to the following criteria.

[0205] <Clogging> A: No salt that could cause clogging is observed in the opening. B: A small amount of salt is observed at the opening, but the opening is sufficiently secured. C: Salt is observed at the opening, but no blockage is observed. D: Salt is observed in the opening, and some blockage is observed.

[0206] The amount of washing liquid required to produce 10 kg of toner was evaluated according to the following criteria.

[0207] <Amount of cleaning solution> A: Less than 40 kg of cleaning fluid is used B: The amount of cleaning fluid used is 40 kg or more but less than 80 kg C: The amount of cleaning fluid used is 80 kg or more but less than 160 kg D: The amount of cleaning fluid used is 160 kg or more.

[0208] The evaluation results are shown in Table 5.

[0209] (drying process) Subsequently, a drying step was carried out using a Jet Turbo Dryer (manufactured by Hiraiwa Iron Works Co., Ltd.), which is a loop-type airflow dryer, under the following conditions to obtain toner particles 1. Blowing temperature: 70℃ Airflow volume: 1m 3 / min Wet toner particle supply rate: 5kg / h

[0210] The amount of surface wax of toner particles 1 was 0%, and the amount of metal ions was 0.0005 mg / g. Table 4 shows the physical properties of the obtained toner particles 1.

[0211] (External addition process) Toner particles 1 100.0 parts Silica particles (RX200: primary average particle size 12 nm, HMDS treatment, manufactured by Nippon Aerosil Co., Ltd.) 1.5 parts The above materials were externally added and mixed using an FM10C (manufactured by Nippon Coke & Engineering Co., Ltd.). The external addition conditions were as follows: the lower blade was set to A0 blade, the gap between the blade and the deflector wall was set to 20 mm, the amount of toner particles charged was 2.0 kg, and the rotation speed was set to 66.6 s -1 The external addition time was 10 minutes, and the cooling water temperature was 20°C and the flow rate was 10 L / min.

[0212] Thereafter, the mixture was sieved through a mesh with 37 μm openings to obtain Toner 1. The physical properties of Toner 1 are shown in Table 4.

[0213] [Toner 2-33] Toner particles 2 to 33 and toners 2 to 33 were obtained in the same manner as in the production example of toner 1, except that the conditions were changed to those shown in Table 3. The physical properties of toner particles 2 to 33 are shown in Table 4. Furthermore, evaluations of clogging and the amount of washing liquid in the washing step of toner particles 2 to 33 are shown in Table 5.

[0214] [Table 3] *If the cleaning solution item says "ion-exchanged water," it means that ion-exchanged water that does not contain fine bubbles was used.

[0215] [Table 4] *In the presence / absence column, if the substance is contained, it is marked with a circle, and if it is not contained, it is marked with an x.

[0216] [Examples 1 to 28, Comparative Examples 1 to 5] Using the above toners 1 to 33, evaluation was carried out in the combinations shown in Table 5. The evaluation results are shown in Table 5.

[0217] The evaluation method and evaluation criteria of the present invention will be described below.

[0218] The image forming apparatus used was a commercially available laser printer, LBP-712Ci (manufactured by Canon), modified to have a process speed of 210 mm / sec, and a commercially available process cartridge, the toner cartridge 040H (cyan) (manufactured by Canon). The product toner was removed from the cartridge, the cartridge was cleaned with an air blower, and then 156 g of the toner of the present invention was filled. The evaluation was performed by removing the product toner from each of the yellow, magenta, and black stations, and inserting the yellow, magenta, and black cartridges with the remaining toner amount detection mechanism disabled.

[0219] <H / Hカブリ> The modified machine and a process cartridge filled with the toner obtained by the manufacturing method of the present invention were left standing in a high temperature and high humidity environment (30° C. / 80% RH, hereinafter referred to as H / H environment) for 24 hours.

[0220] In a H / H environment, Canon color laser copy paper (A4: 81.4 g / m) was used as transfer paper (printing paper). 2) A horizontal line image with a printing rate of 1% was output 3000 sheets in a sequence with a 3 - second pause every 2 sheets printed.

[0221] Next, after standing still for 60 hours in an H / H environment, the process speed was changed to 70 mm / sec, and a completely white image with 0% printing was output on BROCHURE PAPER 150g GLOSSY paper (manufactured by HP: 150 g / m 2 ) One sheet. The fog density above the completely white image was calculated and evaluated according to the following criteria.

[0222] For calculating the fog density, a "White Luminance Meter TC - 6DS" (manufactured by Tokyo Denshoku Co., Ltd.) was used. The difference between the whiteness of the white background part (completely white image) of the evaluation paper and the whiteness of the transfer paper was calculated and taken as the fog density (%). An amber filter was used. When the chargeability of the toner is low, toner is likely to be developed on the white background part, resulting in fog. (Evaluation Criteria) A: Fog density less than 0.5% B: Fog density 0.5% or more and less than 2.0% C: Fog density 2.0% or more and less than 5.0% D: Fog density 5.0% or more

[0223] <H / H Charge Amount> The same output was continuously performed, and printing was stopped during image formation. The process cartridge was taken out, and the toner charge amount on the developing roller immediately after passing through the regulating blade was measured. The H / H charge amount was evaluated according to the following criteria.

[0224] The charge amount on the developing roller was measured using a Faraday cage, as shown in the perspective view of Figure 1. The inside (right side of the figure) was depressurized to suck in the toner on the developing roller, and a toner filter 133 was installed to collect the toner. Reference numeral 131 denotes the suction part, and 132 denotes the holder. The charge amount per unit mass, Q / M (μC / g), was calculated from the mass M of the collected toner and the charge Q measured directly with a coulomb meter. The absolute value of the resulting toner charge amount (Q / M) was taken as the toner charge amount, and the results were ranked as follows: When the amount of metal ions on the toner surface is high, chargeability is likely to decrease due to moisture absorption. Furthermore, when the toner surface has few carboxyl groups, which serve as charging sites, the charge amount is also likely to decrease. (Evaluation criteria) A:40μC / g or more B: 30μC / g or more, less than 40μC / g C: 20μC / g or more, less than 30μC / g D: Less than 20 μC / g

[0225] <Transfer gap> After evaluating the amount of charge, an 8mm grid consisting of repeated line widths of 200μm, 500μm, 1mm, and 2mm was printed on Brochure Paper 150g Glossy paper (manufactured by HP: 150g / m 2 The print was made on both sides of a sheet of paper. Ten randomly selected spots on the second print were visually inspected and observed with a magnifying glass (×30), and ranked according to the following criteria: If the release agent or plasticizer is exposed on the toner surface, the toner adheres to the drum more strongly, making it more likely that voids will occur during transfer. (Evaluation criteria) A: No voids in transfer. B: Observation using a 30x magnifying glass reveals a void in the transfer in part of the field of view. C: Partial voids in the transfer were visually confirmed. D: Transfer voids can be visually confirmed throughout the entire image.

[0226] [Table 5] [Explanation of symbols]

[0227] 131 suction part, 132 holder, 133 toner filter

Claims

1. A toner manufacturing method including a washing step of washing resin particles with a washing liquid, The resin particles have a functional group -(COO - ) n A n+ (In the formula, A n+ represents a metal ion or an ammonium ion, and n represents an integer of 1 or more and 3 or less, The cleaning solution contains fine bubbles, The number average particle size of the fine bubbles in the cleaning solution is 1.0 × 10 1 nm or more 1.0×10 5 nm or less, The method for producing a toner, wherein the zeta potential of the fine bubbles in the cleaning solution is -60 mV or more and 0 mV or less.

2. 2. The method for producing a toner according to claim 1, wherein the acid value of the surface of the resin particles is 0.02 mgKOH / g or more and 1.00 mgKOH / g or less.

3. The number concentration of the fine bubbles in the cleaning solution is 1.0 × 10 4 3. The method for producing a toner according to claim 1, wherein the toner concentration is 1 / mL or more.

4. 3. The method for producing a toner according to claim 1, wherein the zeta potential of the fine bubbles in the cleaning solution is −30 mV or more and −10 mV or less.

5. The number average particle diameter of the fine bubbles in the cleaning solution is 1.0 × 10 1 nm or more 1.0×10 3 3. The method for producing a toner according to claim 1, wherein the particle size is 0.1 nm or less.

6. 3. The method for producing a toner according to claim 1, wherein the washing step involves passing the washing liquid through a cake containing the resin particles to wash the resin particles.

7. The method for producing toner according to claim 6, wherein in the washing step, the cake to be washed is continuously washed while being transferred.

8. 3. The method for producing a toner according to claim 1, wherein a ratio P / W of a mass P of the resin particles in the washing step to a mass W of the washing liquid used in the washing step is 0.1 or more and 1.0 or less.

9. The ratio M / W of the mass M of the metal ions or ammonium ions in the resin particles in the washing step to the mass W of the washing solution used in the washing step is 5.0 × 10 -6 3. The method for producing a toner according to claim 1, wherein the following is true:

10. 3. The method for producing a toner according to claim 1, wherein the resin particles have an average circularity of 0.960 or more.

11. 3. The method for producing a toner according to claim 1, wherein a mass reduction rate of the metal ions or ammonium ions (M1-M2) / M1 is 0.50 or more, where M1 is a mass of the metal ions or ammonium ions before the washing step and M2 is a mass of the metal ions or ammonium ions after the washing step.

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