JP5173483B2 - Toner production method - Google Patents

Description

  The present invention relates to a method for producing toner used for developing an electrostatic latent image formed by a method such as electrophotography, electrostatic recording, magnetic recording, or toner jet recording.

  Various methods are known as image forming methods by electrophotography. Generally, an electrostatic latent image is formed on an electrostatic charge image bearing member (hereinafter also referred to as “photosensitive member”) by using a photoconductive substance by various means. Next, the electrostatic latent image is made visible by developing with toner. If necessary, the visible image with toner is transferred to a recording medium such as paper, and then applied to the recording medium by heat or pressure. A copy is obtained by fixing as a toner image. Examples of such an image forming apparatus include a printer and a copying machine.

  In recent years, these printers and copiers are required to increase the resolution of images by digitization, and at the same time, increase the printing or copying speed, or save space and reduce power consumption by downsizing the apparatus. Yes. Various types of fixing devices used in these printers and copiers have been put to practical use, but the most common method is a heat-pressing method using a heat roller. In this method, a fixing sheet as a recording medium to which toner is transferred is provided between a heat roller having a surface made of a material having releasability with respect to toner and a pressure roller that presses the surface. Fixing is performed by passing the toner image surface so as to be in contact with the heat roller side. In this method, since the surface of the heat roller and the toner image surface of the fixing sheet are in contact with each other under pressure, the toner is excellent in thermal efficiency when fusing onto the fixing sheet, and thus a particularly high speed is required. It is suitably used for applications. Further, as a method used for applications requiring low power consumption, a film fixing method can be mentioned as a representative method. This method uses a film unit equipped with a heating device in place of the heat roller, and performs fixing by passing a sheet to be fixed under a relatively low pressure between the film and the pressure roller. It is. In this method, the heat capacity of the film is small and the wait time can be shortened, so that the power consumption can be reduced.

  On the other hand, in order to satisfy the above-mentioned demands for higher speed and lower power consumption, improvement in fixing performance of the toner itself is also required. That is, it is desired to realize a toner that can be fixed at a lower temperature.

  As a general technique for solving the low-temperature fixability of the toner, there are a method of lowering the molecular weight of the binder resin constituting the toner and a method of lowering the glass transition temperature (hereinafter referred to as Tg). However, according to a method in which the molecular weight and Tg of the binder resin are simply lowered, the heat-resistant storage stability of the toner is lowered, and a so-called blocking phenomenon in which agglomeration occurs between the toners in contact with each other in a high temperature environment and becomes a lump. The problem of being easy to occur arises. Further, the toner carrier and the photosensitive member are easily contaminated, causing a problem that the image quality is deteriorated.

  In response to the above problems, various attempts have been proposed to achieve both low-temperature fixability and blocking resistance by coating the surface of core particles containing a resin having a low Tg with resin fine particles containing a resin having a high Tg. Yes.

  For example, by adding an aqueous dispersion of resin fine particles obtained by emulsion polymerization or soap-free emulsion polymerization to polymer particles (core particles) obtained by suspension polymerization, 95% or more of the surface of the polymer particles is obtained. Cover with fine particles. Thereafter, a toner that has been heated to a temperature equal to or higher than the glass transition temperature of the polymer particles to form a surface substantially free of bulges has been proposed (see Patent Document 1).

  Further, the aqueous dispersion of resin particles (core particles) is mixed with fine particles obtained by mixing an acidic group-containing resin with an aqueous medium in the presence of a basic neutralizing agent and phase inversion emulsification, followed by acid. The fine particles are precipitated on the surface of the resin particles, and after removing the liquid medium, the dried powder is stirred and mixed under heating. There has been proposed a toner in which an acidic group-containing resin (resin fine particles) is fixed to the surface of resin particles by the above technique (see Patent Document 2).

  Further, an intermediate layer having a chargeability opposite to that of the toner inner core particles is formed on the surface of the toner inner core particles (core particles), and a resin (resin fine particles) having a chargeability opposite to that of the intermediate layer is formed on the surface of the intermediate layer. A method for forming an outer shell layer is disclosed (see Patent Document 3).

  Alternatively, after the polymer fine particles are adhered to the surface of the toner base particles (core particles), the polymer fine particles are adsorbed and softened, and then the solvent is removed to form a polymer coating layer. It is disclosed (see Patent Document 4).

  In the toner of Patent Document 1 described above, the adhesion of resin fine particles to the core particles is performed only by adjusting the pH of water, which is a medium, and the fine particles are likely to agglomerate with each other. There wasn't. And when it is going to heat in such a state and it is going to obtain the surface without a protrusion, a part of resin fine particle adhering to the surface of a core particle may be embedded inside the core particle. As a result, there is a possibility that the core particles are partially exposed or a part of the contained wax oozes out, so there is room for improvement in order to obtain sufficient blocking resistance.

  Further, the two toners described in the above-mentioned patent documents form a resin fine particle layer by adding acid to an aqueous dispersion to return the acidic groups of the fine particles to an unneutralized state, thereby precipitating the fine particles on the surface of the core particles. ing. However, even in this method, the fine particles are easily aggregated, and the state of precipitation on the surface of the core particles is not necessarily uniform. Moreover, since filtration and drying are performed without heating, the precipitated fine particles may fall off, and there is a possibility that sufficient blocking resistance may not be obtained even if heating and stirring are mixed in this state.

  Also, the three toners in the above-mentioned patent documents have an intermediate layer formed by adhering inorganic fine particles such as tricalcium phosphate or organic fine particles such as benzoguanamine to the core particle dispersion, and further adhering resin fine particles. The outer shell layer is formed. Not only is the manufacturing process complicated, but particularly when inorganic fine particles are used as the intermediate layer, the fixing strength of each layer is not sufficient, and peeling and dropping may occur, and sufficient blocking resistance may not be obtained. was there.

  In addition, the toner of Patent Document 4 described above is obtained by heating resin fine particles obtained by emulsion polymerization in the presence of a nonionic surfactant to a temperature higher than the cloud point of the nonionic surfactant, thereby dispersing the resin fine particles. It is made to adhere to the core particle. However, in this method, the dispersibility of the fine particles sharply decreases at the cloud point, so the adhesion state is not necessarily sufficient, and cleaning is necessary to remove the surfactant before the next step. The process is complicated.

  As described above, in a toner having a capsule structure in which the surface of core particles having a low Tg is coated with resin fine particles having a high Tg, a toner that sufficiently satisfies the low-temperature fixing property and the blocking resistance has not yet been obtained. is the current situation.

JP 2000-112174 A JP 2000-347455 A JP 2003-91093 A JP-A-9-179336

  An object of the present invention is to provide a toner manufacturing method that solves the above-described conventional problems.

  That is, an object of the present invention is to provide a method for producing a toner having excellent low-temperature fixability and excellent blocking resistance particularly in the production of toner by suspension polymerization.

In order to achieve the above object, the toner production method of the present invention comprises: (i) a polymerizable monomer composition containing at least a polymerizable monomer and a colorant in an aqueous medium in which a dispersion stabilizer is dispersed. suspended in, then a first step of obtaining the polymerizable monomer polymerized to the core particle dispersion obtained by dispersing the core particles (a),
(Ii) in the core particle protégé dispersion liquid (A), the dispersion is the same as polarity the core particles to stabilizing agent, and then adding a resin fine particles having a high glass transition temperature than the core particles, the resin a second step of obtaining a dispersion having fine particles were adhered to the surface of the core particle while interposing the dispersion stabilizer particles (B) and,
(Iii) The dispersion stabilizer is soluble in the pH of the dispersion while maintaining the temperature of the dispersion (B) in the range of not less than the glass transition temperature of the core particles and not more than the glass transition temperature of the resin fine particles . by dissolving adjusted to pH region exhibiting, as a third factory to obtain dispersion (C) having a particle obtained by securing the resin fine particles on the surface of the core particles thereby removing the dispersion stabilizer
Through this process, toner particles are generated .

  According to the present invention, it is possible to provide a toner production method having excellent low-temperature fixability and excellent blocking resistance particularly in the production of toner by a suspension polymerization method.

  Hereinafter, the present invention will be described in more detail with reference to preferred embodiments.

  The toner by suspension polymerization is a polymerizable monomer composition in which a colorant and, if necessary, a release agent, a crosslinking agent, and other additives are uniformly dissolved or dispersed in the polymerizable monomer. It is formed, dispersed in an aqueous medium having a dispersion stabilizer together with a polymerization initiator, granulated, and polymerized to obtain polymer particles.

  The present inventors pay attention to the state of polymer particles contained in the dispersion after polymerization in the toner production process by suspension polymerization, and use this as a core particle to make the surface of the core particle uniform and strong. A technique for efficiently and simply forming a layer of resin fine particles has been found, and the present invention has been completed.

  That is, the present invention is achieved by utilizing the dispersion stabilizer remaining in the state of being adsorbed on the surface of the polymer particles after polymerization. When resin fine particles having the same polarity as the polymer particles are added to the dispersion containing the polymer particles, the resin fine particles are attached to the surface of the polymer particles by the electrical action of the dispersion stabilizer. Uniform adhesion is possible.

  In the present invention, the resin fine particles need to have a higher Tg than the polymer particles. That is, when the dispersion stabilizer is removed while maintaining a dispersion of polymer particles having the resin fine particles uniformly adhered in a temperature range of not less than Tg of the polymer particles and not more than Tg of the resin fine particles, The resin fine particles are immobilized on the surface while maintaining the dispersed state of the coalesced particles. Therefore, a uniform and strong resin fine particle layer can be formed on the surface of the polymer particle as a core particle, thereby greatly improving the blocking resistance as a toner while maintaining the low temperature fixability of the core particle. It became possible to improve.

  Hereinafter, an embodiment of a toner manufacturing method according to the present invention will be described in detail according to the steps.

  The 1st process in this invention is a process of obtaining the polymer particle used as a core particle. The core particles can be produced according to a toner production method by a usual suspension polymerization method.

  Specifically, first, at least a colorant is added to the polymerizable monomer that is the main constituent material of the core particles, and these are uniformly dispersed using a disperser such as a homogenizer, a ball mill, a colloid mill, or an ultrasonic disperser. A polymerizable monomer composition dissolved or dispersed is prepared. At this time, in the polymerizable monomer composition, if necessary, a polyfunctional monomer, a chain transfer agent, a wax as a release agent, a charge control agent, a plasticizer, and a dispersant. Such additives can be appropriately added.

  Next, the polymerizable monomer composition is put into an aqueous medium containing a dispersion stabilizer prepared in advance and suspended using a high-speed disperser such as a high-speed stirrer or an ultrasonic disperser. , Granulate.

  The polymerization initiator may be mixed with other additives when preparing the polymerizable monomer composition, or may be mixed into the polymerizable monomer composition just before being suspended in the aqueous medium. Good. Moreover, it can also be added in the state melt | dissolved in the polymerizable monomer and other solvent as needed during granulation or after completion of granulation, ie, just before starting a polymerization reaction.

  In the polymerization reaction, the suspension after granulation is heated to 50 to 90 ° C. and stirred so that the droplet particles in the suspension maintain the particle state and the particles do not float or settle. While doing.

  The said polymerization initiator decomposes | disassembles easily by heating and produces | generates a free radical (radical). The generated radical is added to the unsaturated bond of the polymerizable monomer to newly generate an adduct radical. The generated adduct radical is further added to the unsaturated bond of the polymerizable monomer. By repeating such an addition reaction in a chain, the polymerization reaction proceeds, and core particles containing the polymerizable monomer as a main constituent material are formed.

  In the production of the toner by the suspension polymerization method, the dispersion stabilizer is subsequently removed, washed and dried to obtain toner particles. However, in the present invention, the dispersion stabilizer is not removed, and the dispersion stabilizer is continued in an aqueous medium. Used in the second step.

  The second step in the present invention is a step of attaching resin fine particles to the core particles in the dispersion.

  In this step, while stirring the dispersion, resin fine particles having the same polarity as the core particles and having a higher Tg than the core particles are added in a state of being dispersed in an aqueous medium. In this way, the resin fine particles can be densely and uniformly attached to the core particles in which the dispersion stabilizer is adsorbed on the surface.

  Hereinafter, the second step is also referred to as “attachment step”.

  In the adhering step, it is preferable to slowly add the aqueous dispersion of the resin fine particles in order to prevent the resin fine particles from agglomerating and adhere more uniformly. A preferable addition rate is 0.1 parts by mass / min to 2.0 parts by mass / min as solids of resin fine particles with respect to 100 parts by mass of solids of the dispersion of core particles.

  Furthermore, the third step in the present invention is a step of fixing the resin fine particles adhered to the surface of the core particle via a dispersion stabilizer. In the present invention, the term “fixation” refers to a state in which the resin fine particles are fixed on the surface of the core particles with a strength that does not easily peel off or drop off.

  In this step, the dispersion is first heated to a temperature not lower than Tg of the core particles and not higher than Tg of the resin fine particles. At this time, although the core particles are in a soft state, it is considered that the dispersed state can be maintained because the resin fine particles maintain a sufficient hardness to exhibit steric stability. Next, when the dispersion stabilizer existing between the core particles and the resin fine particles is removed while maintaining such a state, the resin fine particles adhered to the surface of the core particles until the removal is completed. It is considered that a part thereof is embedded in the core particle surface and the remaining part is exposed on the core particle surface. That is, the resin fine particles are stably fixed to the core particles in a state in which they are difficult to peel off. In this way, the inventors consider that it is possible to form a finer, more uniform and stronger resin fine particle layer than in the past.

  Hereinafter, the third step is also referred to as a “fixing step”.

  In the fixing step, the dispersion stabilizer is preferably removed by controlling the pH of the dispersion.

  Removal of the dispersion stabilizer by adjusting the pH is a very simple technique. For example, when a colloid of a water-insoluble or hardly water-soluble inorganic compound is used as the dispersion stabilizer, the dispersion stabilizer is composed of core particles and resin fine particles. Even if it exists between them, it can be easily dissolved and removed by adjusting the pH of the dispersion to the acidic side. The pH can be adjusted usually by adding hydrochloric acid, sulfuric acid or the like. At this time, in order to keep the state of the resin fine particles adhering to the core particles uniform, it is preferable to slowly add the acid. A suitable addition rate is 0.05 parts by mass / min to 2.00 parts by mass / min with respect to 100 parts by mass of the solid content of the core particle dispersion. The acid to be added is preferably used as an aqueous solution having a concentration of 0.1 mol / liter to 0.5 mol / liter.

  After this step, the toner particles can be obtained by filtration by a known method, washing and drying.

  In the fixing step, when the pH is not controlled only by making the core particle dispersion not less than Tg of the core particles and not more than Tg of the resin particles, a dispersion stabilizer exists between the resin particles and the core particles. Therefore, the adhesiveness between the resin fine particles and the core particles is low and sufficient strength cannot be obtained.

  In the fixing step, if the dispersion temperature is set to be not less than the Tg of the core particles and not more than the Tg of the resin fine particles after performing the pH control, the dispersion stabilizer has already eluted at the stage where the pH control is completed. Therefore, the resin fine particles cannot stably exist on the core particles, which is no different from the conventional method in which the resin fine particles are fixed to the core particles from which the dispersion stabilizer has been removed in advance.

  In the present invention, the difference between the Tg of the core particles and the Tg of the resin fine particles is preferably in the range of 10 to 50 ° C. If the difference in Tg is smaller than 10 ° C., the core particles are likely to agglomerate at the time of fixing, and even if they can be fixed, it is difficult to obtain a sufficient effect of improving blocking resistance. On the other hand, if the Tg difference is larger than 50 ° C., the low-temperature fixability is impaired.

  As described above, the present invention can be achieved by attaching the resin fine particles using the dispersion stabilizer used in the polymerization step, and simultaneously removing the dispersion stabilizer and fixing the resin fine particles. In the conventional method as described above, it has been impossible to achieve the object of the present invention.

  In the present invention, as the fourth step, after the fixing step, the pH of the dispersion is adjusted to a pH region in which the dispersion stabilizer reprecipitates, and then heat-treated at a temperature equal to or higher than Tg of the resin fine particles. It is preferable to further have.

  By reprecipitating the dispersion stabilizer, the surface of the particles to which the resin fine particles are fixed is coated with the dispersion stabilizer, so that aggregation of the particles can be suppressed even when heated above the Tg of the resin fine particles. As a result, the layer made of resin fine particles is smoothed and becomes a more homogeneous and dense layer.

  Hereinafter, the fourth step is also referred to as “smoothing step”.

  By passing through the smoothing step, the blocking resistance is further improved, and another effect of improving developability can be obtained.

  In the smoothing step, the same dispersion stabilizer may be added separately when redispersing the dispersion stabilizer. A small amount of a surfactant can also be added.

  After the smoothing step, the dispersion stabilizer is removed with the acid as described above, filtered by a known method, washed and dried to obtain toner particles.

  In the present invention, the resin fine particles preferably cover 90% or more of the surface of the core particles. When the coating is 90% or less, the surface of the core particle is exposed and the blocking resistance is impaired.

  A more preferable range of the coverage is from 100% to 150%. In the present invention, a coating rate exceeding 100% indicates that the resin fine particle layer is a multilayer. That is, it is more preferable that the resin fine particles cover one or more core particles. However, if the coverage exceeds 150%, it is not preferable because sufficient fixing strength cannot be obtained.

  The coverage can also be obtained directly from an observation image of each toner cross section with a transmission electron microscope (TEM). However, when the resin fine particles contain an element specific to the resin (for example, a sulfonic acid group). S) derived from the above, a quantitative analysis of the element contained in the toner is performed using a fluorescent X-ray analyzer (XRF), and it can be obtained by calculation.

In the present invention, the average particle diameter of the resin fine particles is a median diameter value determined by particle size distribution measurement by a laser scattering method, and is preferably in the range of 10 to 100 nm.

  More preferably, it is used in the range of 30 to 70 nm.

If the average particle diameter is less than 10 nm, the fine particles may be embedded too much in the core particles in the fixing step, and thus control is difficult.

Further, when the average particle diameter exceeds 100 nm, it may be difficult to obtain sufficient fixing strength. Therefore, it is difficult to obtain a toner having sufficient blocking resistance in any case.

  The median diameter is a particle diameter defined as a 50% value (central cumulative value) of a cumulative curve of particle size distribution. For example, a laser diffraction / scattering particle size distribution measuring apparatus (LA-) manufactured by HORIBA, Ltd. 920).

  In the present invention, the suitable fixing amount of the resin fine particles is not uniquely determined, and may be appropriately adjusted according to the desired coverage and the particle diameters of the core particles and the resin fine particles. In the present invention, the fixed amount refers to the amount fixed to the core particle surface. In the range of the above-described coverage and average particle diameter, it is preferable that the mass ratio is in the range of 1.0 to 10.0%. If the fixed amount of the resin fine particles is less than 1.0%, it may be difficult to densely coat in the attaching step. When the fixing amount exceeds 10.0%, the toner fixability may be lowered.

  The resin fine particles used in the present invention are preferably composed of self-water dispersible resin fine particles having acidic groups.

  Self-water dispersible resin fine particles do not require the addition of a separate surfactant, and the dispersion capacity of the resin fine particles can be adjusted by adjusting the pH. Can be immobilized on the core particles. Examples of the acidic group include acidic groups such as a carboxyl group, a sulfonic acid group, and a phosphoric acid group. Among these, a carboxyl group, a sulfonic acid group, or a combination thereof is preferably used, and at least a sulfonic acid group is used. It is particularly preferable that the toner is contained in terms of imparting good chargeability to the toner.

  Further, the resin fine particles preferably have an acid value of 5.0 to 40.0 mgKOH / g. More preferably, it is used in the range of 10.0 to 25.0 mg KOH / g.

  When the acid value is less than 5.0 mgKOH / g, fine particles having sufficient self-water dispersibility cannot be obtained, and when the acid value is higher than 40.0 mgKOH / g, the moisture absorption when the toner is formed. This is not preferable because the chargeability increases and the stability of charging may be impaired. In addition, the electric repulsion between the resin fine particles increases, and the resin fine particles that do not adhere to the surface of the core particles in the adhesion step and remain dispersed in the aqueous medium tend to increase.

  In addition, the acid value here represents content of the said acidic group, and when an acidic group is a salt state, it shows the value computed as what returned to the acid state. The acid value of the resin fine particles is represented by the amount of potassium hydroxide required to neutralize the functional group contained in 1 g of the resin, and is determined by the following method.

The basic operation is based on JISK-0070. This method is particularly suitable for obtaining the acid value of a carboxylic acid group.
1) First, 0.5 to 2.0 g of the sample is precisely weighed in a 300 ml beaker, and the weight at this time is defined as Wg. When the functional group of the sample is in a salt state, a sample that has been returned to an acid state in advance is used.
2) To this, 150 ml of a mixed solution of toluene / ethanol (4/1) is added and dissolved.
3) Titrate with 0.1 mol / l KOH ethanol solution. The titration can be performed, for example, using automatic titration using a potentiometric titration measuring device AT-400 (winworkstation) manufactured by Kyoto Electronics Co., Ltd. and an ABP-410 electric burette.
4) The consumption of the KOH solution at this time is Sml. At the same time, a blank is measured, and the consumption of KOH at this time is defined as Bml.
5) Calculate the acid value according to the following formula. In the formula, f is a factor of KOH.
Acid value (mgKOH / g) = {(SB) × 0.1f × 56.1} / W

  Moreover, when calculating | requiring the acid value of the sulfonic acid group in resin fine particles, quantitative analysis of S element is performed, for example using a fluorescent X-ray-analysis apparatus (XRF), and the functional group equivalent contained in 1g of resin is made into potassium hydroxide. It can be calculated in terms of the amount.

  As a method for producing the self-water dispersible resin fine particles as described above, there is a phase inversion emulsification method.

  In the phase inversion emulsification method, a resin having self-water dispersibility or a resin capable of expressing self-water dispersibility by neutralization is used. Here, the resin having self-water dispersibility is a resin containing a functional group capable of self-dispersion in an aqueous medium in the molecule, specifically, a resin containing an acidic group or a salt thereof. . Further, a resin that can exhibit self-water dispersibility by neutralization is a resin that contains an acidic group in a molecule that has increased hydrophilicity by neutralization and can be self-dispersed in an aqueous medium.

  When these resins are dissolved in an organic solvent, a neutralizing agent is added as necessary, and mixed with an aqueous medium while stirring, the solution of the resin undergoes phase inversion emulsification to produce fine particles. The organic solvent is removed using a method such as heating and decompression after phase inversion emulsification.

  Thus, according to the phase inversion emulsification method, a stable aqueous dispersion of resin fine particles can be obtained without substantially using an emulsifier or a dispersion stabilizer due to the action of the acidic group.

  The resin fine particles obtained in this way can be used for the adhesion process to the core particles as an aqueous dispersion as it is. Further, an acid may be added to the aqueous dispersion to return the acidic group in the resin from the salt state to the acid state, and after filtration and washing, the acid group may be redispersed in water.

  As the material of the resin, any resin can be used as long as it can be used as a binder resin for toner, and resins such as vinyl resins, polyester resins, epoxy resins, and urethane resins are used. Therefore, the low-temperature fixability of the core particles is preferably inhibited.

  As the dispersion stabilizer used in the present invention, a surfactant, an organic dispersant, and an inorganic dispersant can be used, and among these, as described above, a colloid of a water-insoluble or poorly water-soluble inorganic salt is used. Is particularly preferable from the viewpoint of solubility in acids.

  In addition, since inorganic salts have high thermal stability, droplets can be kept stable even when polymerized at high temperatures, and the uniformity of the resin fine particles adhering to the core particles is maintained in the fixing process. This is preferable because it can be fixed as it is. Examples of such inorganic dispersants include tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, magnesium carbonate, calcium carbonate, magnesium hydroxide, calcium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate. And barium sulfate.

  Furthermore, in the present invention, since the dispersion stabilizer is reprecipitated and used in the smoothing step, it is preferably reversible with respect to pH.

  Among the inorganic dispersants described above, tricalcium phosphate can be particularly preferably used because it can be dissolved and precipitated reversibly in the pH range of 3 to 5.

  These dispersion stabilizers are preferably used in an amount of 0.01 to 20 parts by mass with respect to 100 parts by mass of the polymerizable monomer.

  Further, a surfactant may be used in combination. Specifically, commercially available nonionic, anionic and cationic surfactants can be used. For example, sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, potassium stearate, and calcium oleate are preferably used.

  The following are mentioned as a polymerizable monomer used when manufacturing the toner of this invention by a polymerization method.

  For example, styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-ethylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p- tert-butyl styrene, pn-hexyl styrene, pn-octyl, pn-nonyl styrene, pn-decyl styrene, pn-dodecyl styrene, p-methoxy styrene, p-phenyl styrene Styrene monomers, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, n-propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate , 2-chloroethyl acrylate, phenyl acrylate, acrylic acid -Acrylic esters such as hydroxyethyl, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, Examples include methacrylic acid esters such as stearyl methacrylate, phenyl methacrylate, 2-hydroxyethyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, acrylonitrile, methacrylonitrile, and acrylamide.

  Among these polymerizable monomers, it is preferable to use a mixture of styrene or a styrene derivative and another polymerizable monomer from the viewpoint of developing characteristics and durability of the toner. The mixing ratio of these polymerizable monomers may be appropriately selected in consideration of the desired Tg of core particles.

  The polymerization initiator used in the production of the core particles is not particularly limited, and a known peroxide polymerization initiator or azo polymerization initiator can be used.

  As the peroxide polymerization initiator, as peroxy ester polymerization initiator, t-butyl peroxylaurate, t-butyl peroxyneodecanoate, t-butyl peroxypivalate, t-butyl peroxy 2-ethylhexanoate, t-butylperoxyisobutyrate, t-butylperoxyacetate, t-butylperoxyisononanoate, t-butylperoxybenzoate, t-amylperoxyneodecanoate, t-amylperoxypivalate, t-amylperoxy-2-ethylhexanoate, t-amylperoxyacetate, t-amylperoxyisononanoate, t-amylperoxybenzoate, t-hexylperoxyneo Decanoate, t-hexyl peroxypivalate, t-hexyl -Oxy-2-ethylhexanoate, t-hexylperoxybenzoate, α-cumylperoxyneodecanoate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, 1,1 , 3,3-tetramethylbutylperoxyneodecanoate, 1-cyclohexyl-1-methylethylperoxyneodecanoate, 2,5-dimethyl-2,5-bis (2-ethylhexanoylperoxy) Hexane, 2,5-dimethyl-2,5-bis (benzoylperoxy) hexane, t-butylperoxy-3,5,5-trimethylhexanoate, 2,5-dimethyl-2,5-bis (m -Toluoyl peroxy) hexane.

  Further, as peroxydicarbonate-based polymerization initiators, di-n-propyl peroxydicarbonate, di-n-butyl peroxydicarbonate, di-n-pentyl peroxydicarbonate, diisopropyl peroxydicarbonate, di- sec-butyl peroxydicarbonate, di (2-ethylhexyl) peroxydicarbonate, di (2-ethoxyethyl) peroxydicarbonate, di (3-methoxybutyl) peroxydicarbonate, di (4-t-butyl) (Cyclohexyl) peroxydicarbonate.

  Diacyl peroxide polymerization initiators include diisobutyryl peroxide, diisononanoyl peroxide, di-n-octanoyl peroxide, dilauroyl peroxide, distearoyl peroxide, dibenzoyl peroxide, and di-m. -Toluoyl peroxide and benzoyl-m-toluoyl peroxide are mentioned.

  Other peroxy monocarbonates such as t-hexyl peroxyisopropyl monocarbonate, t-butyl peroxyisopropyl monocarbonate, t-butyl peroxy 2-ethylhexyl monocarbonate, t-butyl peroxyallyl monocarbonate, 1,1 -Di-t-hexylperoxycyclohexane, 1,1-di-t-butylperoxy-3,3,5-trimethylcyclohexane, 1,1-di-t-butylperoxycyclohexane, 2,2-di- Examples thereof include peroxyketal-based polymerization initiators such as t-butylperoxybutane, dialkyl peroxide-based polymerization initiators such as dicumyl peroxide, di-t-butyl peroxide, and t-butylcumyl peroxide.

  As the azo polymerization initiator, 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 polymerization initiators, peroxide-based polymerization initiators are preferable because there is little residue of decomposition products. In addition, two or more of these polymerization initiators can be used simultaneously as necessary. At this time, the preferable amount of the polymerization initiator used is 0.1 to 20 parts by mass with respect to 100 parts by mass of the monomer.

  As the colorant used in the toner of the present invention, known ones can be used, and examples thereof include carbon black as a black colorant, magnetic powder, and yellow / magenta / cyan colorants shown below.

  As the yellow colorant, compounds represented by condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and allylamide compounds are used. Specifically, C.I. I. Pigment Yellow 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 109, 110, 111, 128, 129, 147, 168, 180 are preferably used.

  As the magenta colorant, condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds are used. Specifically, C.I. I. Pigment Red 2, 3, 5, 6, 7, 23, 48: 2, 48: 3, 48: 4, 57: 1, 81: 1, 122, 144, 146, 166, 169, 177, 184, 185, 202, 206, 220, 221, and 254 are preferably used.

  As the cyan colorant, copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, basic dye lake compounds are used. Specifically, C.I. I. Pigment Blue 1, 7, 15, 15: 1, 15: 2, 15: 3, 15: 4, 60, 62, 66 are preferably used.

  These colorants can be used alone or in combination, and further in the form of a solid solution. When magnetic powder is used as the black colorant, the amount added is preferably 40 to 150 parts by mass with respect to 100 parts by mass of the polymerizable monomer. When carbon black is used as the black colorant, the amount added is preferably 1 to 20 parts by mass with respect to 100 parts by mass of the polymerizable monomer. Further, in the case of a color toner, it is selected from the viewpoints of hue angle, saturation, brightness, weather resistance, OHP transparency, and dispersibility in the toner, and its preferred addition amount is based on 100 parts by mass of the polymerizable monomer. 1 to 20 parts by mass.

  These colorants need to pay attention to polymerization inhibition and aqueous phase migration, and are preferably subjected to surface modification such as a hydrophobization treatment as necessary. For example, a preferable method for surface-treating a dye-based colorant includes a method in which a polymerizable monomer is polymerized in the presence of a dye in advance, and the obtained colored polymer is added to the monomer composition. . For carbon black, in addition to the same treatment as the above dye, a grafting treatment may be performed with a substance that reacts with the surface functional group of carbon black, for example, polyorganosiloxane.

  Magnetic powder is mainly composed of iron oxide such as triiron tetroxide and γ-iron oxide, and since it is generally hydrophilic, it can be magnetized by interaction with water as a dispersion medium. The powder tends to be unevenly distributed on the particle surface, and the resulting toner particles are inferior in fluidity and frictional charging uniformity due to the magnetic powder exposed on the surface. Therefore, the surface of the magnetic powder is preferably subjected to a hydrophobic treatment uniformly with a coupling agent. Examples of the coupling agent that can be used include a silane coupling agent and a titanium coupling agent, and a silane coupling agent is particularly preferably used.

  The toner of the present invention preferably contains a release agent in order to improve fixability. Usable release agents include, for example, paraffin wax, microcrystalline wax, petroleum wax such as petrolatum and derivatives thereof, montan wax and derivatives thereof, hydrocarbon wax and derivatives thereof by Fischer-Tropsch method, and polyethylene. Examples thereof include polyolefin waxes and derivatives thereof, and natural waxes and derivatives thereof such as carnauba wax and candelilla wax. Derivatives include block copolymers with oxides and vinyl monomers, and graft modified products. Furthermore, higher fatty alcohols, fatty acids such as stearic acid and palmitic acid, or compounds thereof, acid amide waxes, ester waxes, ketones, hydrogenated castor oil and derivatives thereof, plant-based waxes and animal waxes can also be used. These mold release agents may be used independently and may use 2 or more types together.

  Among these release agents, those having a maximum endothermic peak in the region of 40 to 130 ° C. at the time of temperature rise in the DSC curve measured by a differential differential calorimeter are preferable, and further in the region of 45 to 120 ° C. Is more preferable. By using such a release agent, the release property can be effectively expressed while greatly contributing to the low-temperature fixability. When the maximum endothermic peak is less than 40 ° C., the self-aggregating force of the release agent component becomes weak, and as a result, the high temperature offset resistance deteriorates. Further, exudation of the release agent is likely to occur at times other than during fixing, and the charge amount of the toner is reduced, and the durability under high temperature and high humidity is reduced. On the other hand, if the maximum endothermic peak exceeds 130 ° C., the fixing temperature becomes high and low temperature offset tends to occur, which is not preferable. Furthermore, if the maximum endothermic peak temperature is too high, it causes a problem that the release agent component is precipitated during granulation, and the dispersibility of the release agent is lowered.

  The content of the release agent is preferably 1 to 30 parts by mass, and more preferably 3 to 20 parts by mass with respect to 100 parts by mass of the polymerizable monomer. When the content of the release agent is less than 1 part by mass, a sufficient addition effect cannot be obtained and the offset suppressing effect is insufficient. On the other hand, when the amount exceeds 30 parts by mass, the long-term storage stability is deteriorated and the dispersibility of the colorant and other toner materials is deteriorated, resulting in a decrease in fluidity and image characteristics of the toner. Further, exfoliation of the release agent component occurs other than at the time of fixing, resulting in poor durability under high temperature and high humidity.

  In the production of the core particles, a chain transfer agent can be used for the purpose of adjusting the molecular weight. Specific examples include n-pentyl mercaptan, isopentyl mercaptan, 2-methylbutyl mercaptan, n-hexyl mercaptan, n-heptyl mercaptan, n-octyl mercaptan, t-octyl mercaptan, t-nonyl mercaptan, n-dodecyl mercaptan, alkyl mercaptans such as t-dodecyl mercaptan, n-tetradecyl mercaptan, t-tetradecyl mercaptan, n-pentadecyl mercaptan, n-hexadecyl mercaptan, t-hexadecyl mercaptan, stearyl mercaptan, alkyl esters of thioglycolic acid , Alkyl esters of mercaptopropionic acid, halogenated hydrocarbons such as chloroform, carbon tetrachloride, ethylene bromide, carbon tetrabromide, α-methylstyrene dimer And the like.

  These chain transfer agents are not necessarily used, but a preferable addition amount when used is 0.05 to 3 parts by mass with respect to 100 parts by mass of the polymerizable monomer.

  In the production of the core particles, a small amount of a polyfunctional monomer can be used in combination for the purpose of improving high temperature offset resistance.

  Here, the high temperature offset is a decrease in which the toner melted at the time of fixing adheres to the surface of the above-described heat roller or fixing film, and this contaminates the subsequent fixing sheet.

  As the polyfunctional monomer, compounds having two or more polymerizable double bonds are mainly used. For example, aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene, such as ethylene glycol diacrylate and ethylene glycol. Carboxylic acid esters having two double bonds such as dimethacrylate, 1,3-butanediol dimethacrylate, or divinyl compounds such as divinylaniline, divinyl ether, divinyl sulfide, divinyl sulfone, and more than two vinyl groups The compound which has is mentioned.

  These polyfunctional monomers are not necessarily used, but a preferable addition amount when used is 0.01 to 1.00 parts by mass with respect to 100 parts by mass of the polymerizable monomer.

  Moreover, in this invention, you may superpose | polymerize by adding resin in the polymerizable monomer composition mentioned above.

  For example, a polyester resin is a relatively polar resin containing many ester bonds. When this polyester resin is dissolved in the polymerizable monomer composition and polymerized, the resin tends to move to the surface layer of the droplets in the aqueous medium, and is unevenly distributed on the surface of the particle as the polymerization proceeds. Therefore, the granulation property is improved, and the aforementioned release agent can be easily included.

  The said polyester resin can use the normal thing which contains an alcohol component and an acid component at least as a structural component.

  Specific examples of the alcohol component include, for example, divalent alcohols such as ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,3-butanediol, 2,3- Butanediol, diethylene glycol, dipropylene glycol, triethylene glycol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanediol, neopentyl glycol, 2,2,4-trimethylpentane-1,3 -Diol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, bisphenol A, hydrogenated bisphenol A, bisphenol derivatives represented by the following general formula (I), and diols represented by the following formula (II) This Can.

  Further, as trihydric or higher alcohols, sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol, 1 , 2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene. .

  These alcohol components may be used alone or in a mixed state.

（式中、Ｒはエチレン又はプロピレン基であり、ｘ及びｙはそれぞれ１以上の整数であり、且つｘ＋ｙの平均値は２乃至１０である。）

(In the formula, R is an ethylene or propylene group, x and y are each an integer of 1 or more, and the average value of x + y is 2 to 10.)

（式中、Ｒ’は−ＣＨ₂ＣＨ₂−、−ＣＨ₂ＣＨ（ＣＨ₃）−、または−ＣＨ₂−Ｃ（ＣＨ₃）₂−である。）

(In the formula, R ′ represents —CH ₂ CH ₂ —, —CH ₂ CH (CH ₃ ) —, or —CH ₂ —C (CH ₃ ) ₂ —).

  Specific examples of the acid component include divalent carboxylic acids such as naphthalenedicarboxylic acid, phthalic acid, isophthalic acid, terephthalic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, succinic acid, adipic acid, sebacic acid, Examples thereof include dicarboxylic acids such as azelaic acid; dicarboxylic anhydrides such as phthalic anhydride and maleic anhydride, and lower alkyl esters of dicarboxylic acids such as dimethyl terephthalate, dimethyl maleate and dimethyl adipate. Particularly preferred are lower alkyl esters of dicarboxylic acids such as dimethyl terephthalate, dimethyl maleate, and dimethyl adipate, or derivatives thereof.

  Moreover, you may make it bridge | crosslink by using trivalent or more carboxylic acid. Examples of the crosslinking component include trimellitic acid, tri n-ethyl 1,2,4-tricarboxylate, tri n-butyl 1,2,4-tricarboxylate, tri n-hexyl 1,2,4-tricarboxylate, Triisobutyl 2,4-benzenetricarboxylate, tri-n-octyl 1,2,4-benzenetricarboxylate, tri-2-ethylhexyl 1,2,4-benzenetricarboxylate and lower alkyl esters of tricarboxylic acid can be used.

  Moreover, you may use a monovalent | monohydric carboxylic acid component and a monovalent alcohol component to such an extent that the characteristic of a polyester resin is not impaired. For example, as a monovalent carboxylic acid component, benzoic acid, naphthalenecarboxylic acid, salicylic acid, 4-methylbenzoic acid, 3-methylbenzoic acid, phenoxyacetic acid, biphenylcarboxylic acid, acetic acid, propionic acid, butyric acid, octanoic acid, decanoic acid, Dodecanoic acid and stearic acid can be added. In addition, n-butanol, isobutanol, sec-butanol, n-hexanol, n-octanol, lauryl alcohol, 2-ethylhexanol, decanol, cyclohexanol, benzyl alcohol, dodecyl alcohol are added as monovalent alcohol components. can do.

  The addition amount of the resin is preferably in the range of 1 to 20 parts by mass with respect to 100 parts by mass of the polymerizable monomer. If it is less than 1 part by mass, the effect of addition is small, and if it exceeds 20 parts by mass, it becomes difficult to design various physical properties of the toner.

  The toner of the present invention can contain a charge control agent as necessary for the purpose of stabilizing the charge characteristics. As a method of inclusion, there are a method of adding the toner particles inside and a method of externally adding them. As the charge control agent, a known one can be used, but when added inside, a charge control agent having a low polymerization inhibitory property and substantially free from a solubilized product in an aqueous dispersion medium is particularly preferable. Specific compounds include, as negative charge control agents, metal compounds of aromatic carboxylic acids such as salicylic acid, alkyl salicylic acid, dialkyl salicylic acid, naphthoic acid, dicarboxylic acid, metal salts or metal complexes of azo dyes or azo pigments, Examples thereof include a polymer compound having a sulfonic acid or carboxylic acid group in the side chain, a boron compound, a urea compound, a silicon compound, and a calixarene. Examples of positive charge control agents include quaternary ammonium salts, polymer compounds having quaternary ammonium salts in the side chain, guanidine compounds, nigrosine compounds, and imidazole compounds.

  The amount of use of these charge control agents is determined by the toner production method including the type of binder resin, the presence or absence of other additives, and the dispersion method, and is not uniquely limited. When added internally, it is preferably used in the range of 0.1 to 10 parts by mass, more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the binder resin. In the case of external addition, the amount is preferably 0.005 to 1.0 part by mass, more preferably 0.01 to 0.3 part by mass with respect to 100 parts by mass of the toner.

  The toner of the present invention is preferably externally added with a fluidity improver to improve image quality. As the fluidity improver, inorganic fine powders such as silicate fine powder, titanium oxide, and aluminum oxide are preferably used. These inorganic fine powders are preferably hydrophobized with a hydrophobizing agent such as a silane coupling agent, silicone oil or a mixture thereof.

  The toner of the present invention can be used as it is as a one-component developer or as a two-component developer by mixing with a magnetic carrier. When used as a two-component developer, the average particle size of the carrier to be mixed is preferably 10 to 100 μm, and the toner concentration in the developer is preferably 2 to 15% by mass.

  Here, in the present invention, the glass transition temperature (Tg) of the toner and resin fine particles can be determined as follows using, for example, a differential scanning calorimeter (Q1000) manufactured by TA Instruments.

  First, about 6 mg of a sample is precisely weighed in an aluminum pan, and an empty aluminum pan is prepared as a reference pan. In a nitrogen atmosphere, the measurement temperature range is 20 to 150 ° C., the temperature rising rate is 2 ° C./min, and the modulation amplitude is ± 0. The measurement is performed at 6 ° C. and at a frequency of once / minute.

  From the reversing heat flow curve at the time of temperature rise obtained by measurement, draw a tangent line between the endothermic curve and the front and back baselines, find the midpoint of the straight line connecting the intersections of each tangent line, and this is the glass transition Let it be temperature.

  The average particle size and particle size distribution of the toner can be measured using a Coulter Counter TA-II type or Coulter Multisizer (both manufactured by Coulter). In the present invention, a Coulter multisizer was used, and an interface (manufactured by Nikka Machine Co., Ltd.) for outputting the number distribution and the volume distribution and a PC9801 personal computer (manufactured by NEC Corporation) were connected thereto. As the electrolytic solution, a 1% NaCl aqueous solution prepared using primary sodium chloride was used.

  As a measurement method, 0.1 to 5 ml of a surfactant, preferably alkylbenzene sulfonate, is added as a dispersant to 100 to 150 ml of the electrolytic solution, and 2 to 20 mg of a measurement sample is further added. Next, the electrolytic solution is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the volume and number of particles having a size of 2 μm or more are measured by the Coulter Multisizer using a 100 μm aperture as an aperture. Calculate the distribution. Then, the weight average particle diameter (D4) obtained from the volume distribution and the number average particle diameter (D1) obtained from the number distribution are obtained.

  The average circularity of the toner obtained by the present invention is preferably 0.970 or more. The average circularity is an index representing the degree of unevenness of toner particles, and is 1.000 when the toner is a perfect sphere, and the value becomes smaller as the surface shape becomes more complicated. That is, that the average circularity is 0.970 or more means that the toner shape is substantially spherical. The toner having such a shape is likely to be uniformly charged, and is effective in suppressing fog and sleeve ghost. Further, since the toner ears formed on the toner carrier are uniform, control in the developing unit is facilitated. Furthermore, since it has a spherical shape, it has good fluidity and is not easily stressed in the developing device, so that the chargeability is not easily lowered even when used for a long time under high humidity. Further, since heat and pressure are easily applied to the entire toner even at the time of fixing, it contributes to improvement of fixing properties.

  The average circularity in the present invention was measured using a flow type particle image analyzer (FPIA-3000 type) manufactured by Sysmex Corporation.

  As a specific measurement method, a suitable amount of a surfactant, preferably alkylbenzene sulfonate, is added to 20 ml of ion-exchanged water, 0.02 g of a measurement sample is added, and a desktop with an oscillation frequency of 50 kHz and an electrical output of 150 W is added. Dispersion treatment is performed for 2 minutes using a type of ultrasonic cleaner disperser (for example, VS-150 manufactured by Vervo Crea) to obtain a dispersion for measurement. In that case, it cools suitably so that the temperature of a dispersion liquid may become 10 to 40 degreeC.

  For the measurement, the flow type particle image measuring apparatus equipped with a standard objective lens (10 times) is used, and a particle sheath (PSE-900A) manufactured by Sysmex Corporation is used as the sheath liquid. The dispersion prepared in accordance with the above procedure is introduced into the flow type particle image measuring apparatus, 3000 toner particles are measured in the total count mode, and the analysis particle diameter is set to a circle equivalent diameter of 3.00 μm or more and 200.00 μm or less. Limit and determine the average circularity of the toner particles.

  In measurement, automatic focus adjustment is performed using standard latex particles (for example, a product obtained by diluting 5200A manufactured by Duke Scientific with ion-exchanged water) before the measurement is started. Thereafter, it is preferable to perform focus adjustment every two hours from the start of measurement.

  In the examples, a flow-type particle image measuring apparatus that has been calibrated by Sysmex Corporation and has been issued a calibration certificate issued by Sysmex Corporation has an analysis particle diameter of 3.00 μm or more. Except for limiting to 200.00 μm or less, measurement was performed under the measurement and analysis conditions when the calibration certificate was received.

  EXAMPLES Hereinafter, although a manufacture example and an Example demonstrate this invention concretely, these do not limit this invention at all.

<Synthesis Example 1: Resin fine particle dispersion (a)>
(Production of polyester resin)
The following monomers are charged into a reaction vessel equipped with a stirrer, condenser, thermometer, and nitrogen introduction tube, 0.03 parts by mass of tetrabutoxy titanate is added as an esterification catalyst, and the temperature is raised to 220 ° C. in a nitrogen atmosphere. Then, the reaction was carried out for 5 hours with stirring.
Bisphenol A-propylene oxide 2-mol adduct: 49.2 parts by mass Ethylene glycol: 8.9 parts by mass Terephthalic acid: 21.7 parts by mass Isophthalic acid: 14.4 parts by mass 5-sodium sulfoisophthalic acid: 5.8 parts by mass Part

  Next, the reaction was further carried out for 5 hours while reducing the pressure inside the reaction vessel to 5 to 20 mmHg to obtain a polyester resin.

(Preparation of resin fine particle dispersion)
A reaction vessel equipped with a stirrer, a condenser, a thermometer, and a nitrogen introduction tube was charged with 100.0 parts by mass of the obtained polyester resin, 45.0 parts by mass of methyl ethyl ketone, and 45.0 parts by mass of tetrahydrofuran, and heated to 80 ° C. And dissolved.

  Next, under stirring, 300.0 parts by mass of ion-exchanged water at 80 ° C. was added and dispersed in water, and then the resulting aqueous dispersion was transferred to a distillation apparatus and distilled until the fraction temperature reached 100 ° C. It was.

  After cooling, ion-exchanged water was added to the obtained aqueous dispersion to adjust the resin concentration in the dispersion to 20%. This was designated as resin fine particle dispersion (a).

<Synthesis Example 2: Resin fine particle dispersion (b)>
(Production of polyester resin)
The following monomers were charged into a reaction vessel equipped with a stirrer, condenser, thermometer and nitrogen introduction tube, 0.03 parts by mass of tetrabutoxy titanate was added as an esterification catalyst, and the temperature was raised to 220 ° C. in a nitrogen atmosphere. Warmed and reacted for 5 hours with stirring.
Bisphenol A-propylene oxide 2 mol adduct: 49.9 parts by mass Ethylene glycol: 9.0 parts by mass Terephthalic acid: 20.5 parts by mass Isophthalic acid: 13.7 parts by mass

  Next, 7.0 parts by mass of trimellitic anhydride was added, and the reaction was further performed for 5 hours while reducing the pressure in the reaction vessel to 5 to 20 mmHg to obtain a polyester resin.

(Preparation of resin fine particle dispersion)
In a reaction vessel equipped with a stirrer, condenser, thermometer, and nitrogen introduction tube, 100.0 parts by mass of the obtained polyester resin and 75.0 parts by mass of butyl cellosolve were charged and dissolved by heating to 90 ° C. Until cooled.

  Subsequently, 18.0 parts by mass of a 1 mol / liter aqueous ammonia solution was added, and the mixture was stirred for 30 minutes while maintaining the above temperature. Then, 300.0 parts by mass of ion-exchanged water at 70 ° C. was added and dispersed in water. . The obtained aqueous dispersion was transferred to a distillation apparatus and distilled until the fraction temperature reached 100 ° C.

  After cooling, ion-exchanged water was added to the obtained aqueous dispersion to adjust the resin concentration in the dispersion to 20%. This was designated as resin fine particle dispersion (b).

<Synthesis Examples 3 and 4: Resin fine particle dispersions (c) and (d)>
In Synthesis Example 1, the stirring time and the ion exchange water addition conditions were appropriately changed to obtain two types of polyester resin aqueous dispersions having different average particle diameters. This was designated as resin fine particle dispersions (c) and (d).

<Synthesis Example 5: Resin fine particle dispersion (e)>
In Synthesis Example 1, an aqueous dispersion of a polyester resin was obtained in the same manner as in Synthesis Example 1, except that the monomer charge was changed as follows. This was designated as resin fine particle dispersion (e).
Bisphenol A-propylene oxide 2-mol adduct: 50.0 parts by mass Ethylene glycol: 9.0 parts by mass Terephthalic acid: 23.5 parts by mass Isophthalic acid: 15.6 parts by mass 5-sodium sulfoisophthalic acid: 2.0 parts by mass Part

<Synthesis Example 6: Resin fine particle dispersion (f)>
In Synthesis Example 1, an aqueous dispersion of a polyester resin was obtained in the same manner as in Synthesis Example 1, except that the monomer charge was changed as follows. This was designated as resin fine particle dispersion (f).
Bisphenol A-propylene oxide 2-mol adduct: 46.5 parts by mass Ethylene glycol: 8.4 parts by mass Terephthalic acid: 15.1 parts by mass Isophthalic acid: 10.0 parts by mass 5-sodium sulfoisophthalic acid: 20.0 parts by mass Part

<Synthesis Example 7: Resin fine particle dispersion (g)>
In Synthesis Example 1, an aqueous dispersion of a polyester resin was obtained in the same manner as in Synthesis Example 1, except that the monomer charge was changed as follows. This was designated as resin fine particle dispersion (g).
Bisphenol A-propylene oxide 2 mol adduct: 62.4 parts by mass Ethylene glycol: 7.5 parts by mass Terephthalic acid: 12.4 parts by mass Isophthalic acid: 12.3 parts by mass Fumaric acid: 8.8 parts by mass 5-sodium Sulfoisophthalic acid: 5.4 parts by mass

<Synthesis Example 8: Resin fine particle dispersion (h)>
(Production of styrene / acrylic resin)
A reaction vessel equipped with a stirrer, a condenser, a thermometer, and a nitrogen introduction tube was charged with 350.0 parts by mass of ion-exchanged water and 0.5 parts by mass of sodium dodecylbenzenesulfonate, and the temperature was raised to 90 ° C. in a nitrogen atmosphere. Then, 8 parts by mass of 2% aqueous hydrogen peroxide solution and 8 parts by mass of 2% ascorbic acid aqueous solution were added.

  Subsequently, the following monomer mixture, aqueous emulsifier solution and aqueous polymerization initiator solution were added dropwise over 5 hours with stirring.

(Monomer)
Styrene: 94.0 parts by weight Methacrylic acid: 3.3 parts by weight Methyl methacrylate: 2.6 parts by weight t-dodecyl mercaptan: 0.05 parts by weight (Emulsifier)
Sodium dodecylbenzenesulfonate: 0.3 parts by mass Polyoxyethylene nonylphenyl ether: 0.01 parts by mass Ion-exchanged water: 20.0 parts by mass (polymerization initiator)
2% aqueous hydrogen peroxide solution: 40.0 parts by mass 2% ascorbic acid aqueous solution: 40.0 parts by mass

  After dropping, the polymerization reaction was further carried out for 2 hours while maintaining the above temperature, followed by cooling to obtain an aqueous dispersion of styrene / acrylic resin.

  Ion exchange water was added to the obtained aqueous dispersion to adjust the resin concentration in the dispersion to 20%. This was designated as resin fine particle dispersion (h).

  For the resin fine particle dispersions (a) to (h) thus obtained, the average particle size of the fine particles in each dispersion was measured using a laser diffraction / scattering particle size distribution measuring apparatus. Further, the acid value and glass transition temperature of the resin used in each dispersion were measured. With respect to the resin fine particle dispersion (h), a part of the dispersion was washed and dried, and the one taken out as a solid content was measured. The acid values of the resin fine particle dispersions (a) and (c) to (h) having sulfonic acid groups were calculated by measuring the amount of S element in each resin using a fluorescent X-ray analyzer (XRF). It is what I asked for. The results are summarized in Table 1 respectively.

<Example 1>
(Preparation of pigment dispersion paste)
Styrene: 212.7 parts by mass Cu phthalocyanine (Pigment Blue 15: 3): 19.7 parts by mass After sufficiently premixing the above materials in a container, an attritor (manufactured by Mitsui Miike Chemical Co., Ltd.) is kept at 20 ° C. Was uniformly dispersed and mixed for about 4 hours to prepare a pigment dispersion paste.

(First step)
While placing 390.0 parts by mass of a 0.1 mol / liter-sodium phosphate (Na ₃ PO ₄ ) aqueous solution into 1152.0 parts by mass of ion-exchanged water and stirring using CLEARMIX (M Technique Co., Ltd.) After heating to 60 ° C., 58.0 parts by mass of 1.0 mol / liter-calcium chloride (CaCl ₂ ) aqueous solution was added and stirring was continued, and tricalcium phosphate (Ca ₃ (PO ₄ ) ₂ ) was added. An aqueous medium containing a dispersion stabilizer consisting of:

On the other hand, the following materials were added to the pigment dispersion paste and dispersed and mixed using an attritor (manufactured by Mitsui Miike Chemical Industries) to prepare a monomer composition.
n-butyl acrylate: 114.9 parts by mass Amorphous polyester: 15.1 parts by weight (polycondensate of propylene oxide-modified bisphenol A and isophthalic acid, Tg = 58 ° C., Mw = 7800, acid value 13)
Aluminum salicylate compound: 3.1 parts by mass (Bontron E-88: manufactured by Orient Chemical Co., Ltd.)
Divinylbenzene: 0.049 parts by mass

  The monomer composition was heated to 60 ° C., and 39 parts by weight of carnauba wax was added and mixed and dissolved. Next, 7.8 parts by mass of 2,2'-azobis (2,4-dimethylvaleronitrile): 7.8 parts by mass was further added and dissolved as a polymerization initiator. This was put into the aqueous medium, and granulated by stirring for 10 minutes at 10,000 rpm in a nitrogen atmosphere at 60 ° C. using CLEARMIX (M Technique Co., Ltd.).

  Furthermore, the obtained suspension was polymerized at 60 ° C. for 10 hours while being stirred with a paddle stirring blade at a rotation speed of 150 rotations / minute.

  After the completion of the polymerization, the obtained dispersion of polymer particles was cooled, and ion exchange water was added to adjust the concentration of polymer particles in the dispersion to 20%. This was designated as core particle dispersion (A).

A part of the dispersion (A) was taken out, added with dilute hydrochloric acid, filtered, washed and dried, and used to measure the glass transition temperature (Tg) and the weight average particle diameter (D4) of the obtained core particles. .

The core particles had a glass transition temperature (Tg) of 45 ° C. and a weight average particle diameter (D4) of 6.5 μm .

(Second step)
The resin particle dispersion (a) 15.0 obtained in Synthesis Example 1 is added to 500.0 parts by mass (solid content: 100.0 parts by mass) of the core particle dispersion (A) obtained through the first step. Part by mass (solid content: 3.0 parts by mass) was added at a dropping rate of 1.0 part by mass / min.

  Subsequently, stirring was performed at 200 rpm for 30 minutes.

  A part of the dispersion was taken out, filtered, washed, and dried, and observed with a scanning electron microscope (SEM). As a result, it was confirmed that the surface was uniformly covered with resin fine particles.

  Thus, a dispersion liquid (B) in which resin fine particles adhered to the core particle surfaces was obtained.

(Third step)
The dispersion (B) obtained by passing through the second step and having the fine resin particles adhered thereto was heated to 55 ° C. while stirring at 200 rpm.

  Subsequently, 0.2 mol / liter of dilute hydrochloric acid is added dropwise to the dispersion (B) at a dropping rate of 1.0 part by mass / min, and dilute hydrochloric acid is added until the pH of the dispersion (B) reaches 1.5. Continued. Stirring was further continued for 2 hours to obtain a dispersion (C) in which resin fine particles were fixed.

(Fourth process)
While the dispersion liquid (C) obtained by passing through the third step and having the resin fine particles fixed thereto is stirred at 200 rpm, a 1 mol / liter sodium hydroxide aqueous solution is added to the dispersion liquid (C) at 10.0. The solution was added dropwise at a dropping rate of parts by mass / min, and the pH of the dispersion (C) was adjusted to 7.2.

  By stirring for 30 minutes in this state, tricalcium phosphate once dissolved was reprecipitated on the core particles to which the resin fine particles were fixed.

  This dispersion was heated to 70 ° C., which is equal to or higher than Tg of the resin fine particles, and further stirred for 2 hours.

  The dispersion was cooled to 20 ° C., diluted hydrochloric acid was added until the pH reached 1.5, filtered, washed, and dried to obtain toner particles 1.

(External addition process)
Toner particles 1: Hydrophobic titanium oxide treated with n-C ₄ H ₉ Si (OCH ₃ ) ₃ on 100.0 parts by mass (BET specific surface area: 110 m ^{2 /} g): 0.8 parts by mass and hexamethyldi Hydrophobic silica treated with silicone oil after silazane treatment (BET specific surface area of 150 m ^{2 /} g): 0.8 part by mass was added and mixed with a Henschel mixer to obtain toner 1.

<Example 2>
In Example 1, resin fine particle dispersion (b) obtained in Synthesis Example 2 instead of resin fine particle dispersion (a): 15.0 parts by mass (solid content: 3.0 parts by mass) in the second step Toner 2 was obtained in the same manner as in Example 1 except that 20.0 parts by mass (solid content: 4.0 parts by mass) was used.

<Example 3>
In Example 1, the fourth step is omitted, and at the end of the third step, the dispersion liquid to which the resin fine particles are fixed is cooled to 20 ° C., filtered, washed and dried. 3 was obtained.

<Example 4>
In Example 1, the amount of the resin fine particle dispersion (a) added in the second step is from 15.0 parts by mass (solid content: 3.0 parts by mass) to 10.0 parts by mass (solid content: 2.0 parts by mass). Toner 4 was obtained in the same manner as in Example 1, except that

<Example 5>
In Example 1, the amount of the resin fine particle dispersion (a) added in the second step is 15.0 parts by mass (solid content: 3.0 parts by mass) to 40.0 parts by mass (solid content: 8.0 parts by mass). Part) Toner 5 was obtained in the same manner as in Example 1 except that the addition was changed.

<Example 6>
In Example 1, the resin fine particle dispersion (c) obtained in Synthesis Example 3 in place of the resin fine particle dispersion (a): 15.0 parts by mass (solid content: 3.0 parts by mass) in the second step : Toner 6 was obtained in the same manner as in Example 1 except that 30.0 parts by mass (solid content: 6.0 parts by mass) was used.

<Example 7>
In Example 1, resin fine particle dispersion (a) obtained in Synthesis Example 4 instead of resin fine particle dispersion (a): 15.0 parts by mass (solid content: 3.0 parts by mass) in the second step : Toner 7 was obtained in the same manner as in Example 1 except that 50.0 parts by mass (solid content: 10.0 parts by mass) was used.

<Example 8>
In Example 1, resin fine particle dispersion (a) obtained in Synthesis Example 5 instead of resin fine particle dispersion (a): 15.0 parts by mass (solid content: 3.0 parts by mass) in the second step : Toner 8 was obtained in the same manner as in Example 1 except that 20.0 parts by mass (solid content: 4.0 parts by mass) was used.

<Example 9>
In Example 1, resin fine particle dispersion (a) obtained in Synthesis Example 6 instead of resin fine particle dispersion (a): 15.0 parts by mass (solid content: 3.0 parts by mass) in the second step : Toner 9 was obtained in the same manner as in Example 1 except that 20.0 parts by mass (solid content: 4.0 parts by mass) was used.

<Example 10>
In Example 3, resin fine particle dispersion (g) obtained in Synthesis Example 7 instead of resin fine particle dispersion (a): 15.0 parts by mass (solid content: 3.0 parts by mass) in the second step The toner 10 was prepared in the same manner as in Example 3 except that 15.0 parts by mass (solid content: 3.0 parts by mass) was used and the heating temperature was changed from 55 ° C. to 50 ° C. in the third step. Obtained.

<Example 11>
In Example 3, resin fine particle dispersion (a) obtained in Synthesis Example 8 instead of resin fine particle dispersion (a): 15.0 parts by mass (solid content: 3.0 parts by mass) in the second step : Toner 11 was prepared in the same manner as in Example 3 except that 55.0 parts by mass (solid content: 11.0 parts by mass) was used and the heating temperature was changed from 55 ° C. to 80 ° C. in the third step. Obtained.

<Comparative Example 1>
In Example 3, Toner 12 was obtained in the same manner as in Example 3 except that the heating temperature was changed from 55 ° C. to 40 ° C. in the third step.

<Comparative example 2>
In Example 3, Toner 13 was obtained in the same manner as in Example 3 except that the heating temperature was changed from 55 ° C. to 70 ° C. in the third step.

  Table 2 summarizes the temperature relationship and the presence or absence of the smoothing step in Examples 1 to 11 and Comparative Examples 1 and 2.

<Comparative Example 3>
In Example 3, a toner 14 was obtained in the same manner as in Example 3 except that the third step was performed as follows.

(Third step)
While stirring the dispersion liquid (B) obtained by passing through the second step at 200 rpm, 0.2 mol / liter of diluted hydrochloric acid was added dropwise at a dropping rate of 1.0 part by mass / min. Then, dropwise addition of dilute hydrochloric acid was continued until the pH of the dispersion (B) reached 1.5. Subsequently, the dispersion was heated to 55 ° C.

  Stirring was further continued for 2 hours to obtain a dispersion (D) in which resin fine particles were fixed.

<Comparative example 4>
In Example 3, a toner 15 was obtained in the same manner as in Example 3 except that the third step was performed as follows.

(Third step)
The dispersion (B) obtained by passing through the second step and having the fine resin particles adhered thereto was heated to 60 ° C. while stirring at 200 rpm. Stirring was further continued for 2 hours to obtain a dispersion (E) to which resin fine particles were fixed.

<Comparative Example 5>
(Preparation of core particles)
Dilute hydrochloric acid was added to the core particle dispersion (A) obtained in the first step of Example 1 to adjust the dispersion (A) to pH 1.5, followed by filtration, washing and drying to obtain core particles.

(Production of toner particles)
The resin fine particle dispersion h shown in Table 1 is added to 60.0 parts by mass of ion-exchanged water, and 60.0 parts by mass (solid content: 12.0 parts by mass). Was gradually added and dispersed uniformly.

  A 1 mol / liter hydrochloric acid aqueous solution was added thereto to adjust the pH of the dispersion to 1.5, and the mixture was stirred for 1 hour. Then, the temperature of the dispersion was raised to 55 ° C., and further stirred for 2 hours. A dispersion (F) was obtained.

  Next, the obtained dispersion liquid (F) was cooled, filtered, washed with water and dried to obtain toner particles.

(Production of toner)
The obtained toner particles were externally added in the same manner as in Example 1 to obtain toner 16.

<Comparative Example 6>
In Comparative Example 5, a dispersion (F) was obtained using the same method, and then 20 parts by mass of ethyl acetate was added dropwise over 1 hour to the dispersion (F). After stirring for 3 hours as it was, ethyl acetate was removed at 50 ° C.

  Subsequently, the toner particles were obtained by filtration, washing and drying.

  The toner particles obtained were externally added in the same manner as in Example 1 to obtain toner 17.

  For the toners obtained in Examples 1 to 11 and Comparative Examples 1 to 6, the amount of fine powder (particle ratio of 0.6 μm or more and 2.0 μm or less as measured by FPIA-3000) was evaluated as the production stability evaluation. And the weight average particle diameter was measured. Moreover, evaluation of low-temperature fixability and blocking resistance was performed according to the procedure described below. The results are summarized in Table 3.

(Manufacturing stability evaluation)
Evaluation criteria of fine powder amount Particle ratio (X) of 0.6 μm or more and 2.0 μm or less when core particles are measured with FPIA-3000 and 0.6 μm or more and 2.0 μm or less when toner particles are measured with FPIA-3000 When taking the ratio (Y / X) of the particle ratio (Y),
A: Y / X is less than 1.00. (The amount of fine powder decreases)
B: Y / X is 1.00 or more and less than 1.25. (Particularly little increase in fine powder)
C: Y / X is 1.25 or more and less than 1.50. (Increase in the amount of fine powder is small)
D: Y / X is 1.50 or more and less than 1.75. (The amount of fine powder increases slightly)
E: Y / X is 1.75 or more. (The amount of fine powder increases)

Evaluation Criteria of Weight Average Particle Size (D4) The ratio (D42 / D41) between the weight average particle size (D41) of the core particles and the weight average particle size (D42) of the toner particles is taken. Judgment criteria are as follows.
A: D42 / D41 is less than 1.05. (Toner particles do not aggregate)
B: D42 / D41 is 1.05 or more and less than 1.10. (Toner particles hardly aggregate)
C: D42 / D41 is 1.10 or more and less than 1.20. (Toner particles slightly aggregate)
D: D42 / D41 is 1.20 or more and less than 1.40. (Toner particles aggregate)
E: D42 / D41 is 1.40 or more. (Toner particles remarkably aggregate)

(Fixability test method)
Toner and a ferrite carrier surface-coated with a silicone resin (average particle size 42 μm) were mixed to a toner concentration of 6% by mass to prepare a two-component developer. An unfixed toner image (0.6 mg / cm ² ) was formed on the image receiving paper (80 g / m ² ) by using a commercially available full-color digital copying machine (CLC700, manufactured by Canon). The fixing unit removed from the copying machine was remodeled so that the fixing temperature could be adjusted, and a fixing test of an unfixed image was performed using this. Under normal temperature and normal humidity (22 ° C., 60% RH), the process speed was set to 190 mm / s, and the toner image was fixed at each temperature while changing the set temperature from 120 every 5 ° C.

In the present invention, the low-temperature fixability is such that no low-temperature offset is observed, and when the obtained fixed image is rubbed with sylbon paper lacking a load of 50 g / cm ² , the density reduction rate before and after rubbing. The fixing temperature at which the temperature was 5% or less was set as the low temperature side starting point. The evaluation criteria for the low-temperature fixing performance are as follows.
A: The low temperature side starting point is 120 ° C. (low temperature fixing performance is particularly excellent)
B: Low temperature side starting point is 125 ° C. (low temperature fixing performance is good)
C: The low temperature side starting point is 130 ° C. (low temperature fixing performance is at a level where there is no problem)
D: Starting point on the low temperature side is 135 ° C. (low temperature fixing performance is slightly inferior)
E: Starting point on the low temperature side is 140 ° C. (low temperature fixing performance is inferior)

(Blocking resistance test method)
10 g of toner is weighed into a 100 ml capacity polycup and placed in a thermostat with an internal temperature of 50 ° C. and left for 5 days. Thereafter, the polycup is taken out, and the state change of the toner inside is visually evaluated. The evaluation criteria are as follows.
A: No change B: There is an aggregate, but loosens immediately C: A little aggregate, difficult to loosen D: Many aggregates, not easily loosened E: Not loosened at all

  From the above table, the toner 1 of Example 1 was excellent in low-temperature fixability and excellent in blocking resistance. The amount of fine powder in the toner was extremely small, and aggregation of the toner was suppressed, and the toner could be produced stably.

  Comparing Example 1 and Example 3, it can be seen that the amount of fine powder is reduced and the blocking resistance is improved through the smoothing step.

  In addition, the results of Example 4 indicate that the blocking resistance decreases when the amount of resin fine particles used in the outer shell decreases. For each toner of Examples 1 and 4, the amount of S element was measured using a fluorescent X-ray analyzer (XRF), and the coverage with fine particles was calculated. As a result, the toner of Example 1 was 99.5%, The toner of Example 4 was found to be 66.3%. Further, when the cross section of each toner was observed with a transmission electron microscope (TEM), the toner of Example 4 was found to have a slight defect portion that was not covered with the outer shell, but the toner of Example 1 was apparent. Above, it was confirmed that it was completely covered.

  From the results of Example 5, when the amount of resin fine particles added increases, the fixing strength cannot be maintained, the amount of fine powder increases, and the fixability is also inhibited.

  From the results of Example 7, when the particle size is large like the resin fine particles (d), the amount added is increased in order to obtain sufficient blocking resistance, and the fixing property is inhibited.

  In addition, the results of Example 10 show that the blocking resistance is lowered when the difference between the glass transition temperature of the resin fine particles and the glass transition temperature of the core particles is small. On the contrary, if the glass transition temperature of the resin fine particles becomes too high, as shown in Example 11, the low-temperature fixability is inhibited.

  When fixed at Tg or less of the core particle as in Comparative Example 1, since the resin fine particles are not fixed to the core particle, the amount of fine powder increases and the blocking resistance is remarkably lowered.

  When the resin particles are fixed at Tg or higher as in Comparative Example 2, the core particles cannot be maintained in a dispersed state and agglomeration occurs.

  As in Comparative Examples 3, 4, 5, and 6, when the resin fine particles are adhered and fixed in a process different from the present invention, it is difficult to form a uniform and fine resin fine particle layer. It is inferior in various performances.

Claims (9)

(I) a polymerizable monomer at least a polymerizable monomer composition containing a colorant, is suspended in an aqueous medium containing dispersed dispersion stabilizer, then polymerizing the polymerizable monomer A first step of obtaining a core particle dispersion (A) in which the core particles are dispersed ;
(Ii) in the core particle protégé dispersion liquid (A), the dispersion is the same as polarity the core particles to stabilizing agent, and then adding a resin fine particles having a high glass transition temperature than the core particles, the resin a second step of obtaining a dispersion having fine particles were adhered to the surface of the core particle while interposing the dispersion stabilizer particles (B) and,
(Iii) The dispersion stabilizer is soluble in the pH of the dispersion while maintaining the temperature of the dispersion (B) in the range of not less than the glass transition temperature of the core particles and not more than the glass transition temperature of the resin fine particles . by dissolving adjusted to pH region exhibiting, as a third factory to obtain dispersion (C) having a particle obtained by securing the resin fine particles on the surface of the core particles thereby removing the dispersion stabilizer
A toner manufacturing method, wherein toner particles are generated by going through the process. A fourth step of adjusting the pH of the dispersion (C) to a pH region where the dispersion stabilizer is reprecipitated, and then heat-treating at a temperature equal to or higher than the glass transition temperature of the resin fine particles;
The toner production method according to claim 1 , further comprising: Wherein as a dispersion stabilizer, method for producing a toner according to claim 1 or 2, characterized by using a water-insoluble or sparingly water-soluble inorganic compound. The toner production method according to claim 3 , wherein tricalcium phosphate is used as the water-insoluble or poorly water-soluble inorganic compound. The resin fine particles, method for producing a toner according to any one of claims 1 to 4, characterized in that it consists of self-water dispersible resin fine particles having a carboxyl group and / or a sulfonic acid group. When the acid value of the resin fine particles, method for producing a toner according to any one of claims 1 to 5, characterized in that a 5.0 to 40.0 mgKOH / g. The average particle diameter of the resin fine particles, method for producing a toner according to any one of claims 1 to 6, characterized in that in the range of 10 to 100 nm. The amount fixation of the resin particles with respect to the core particles, method for producing a toner according to any one of claims 1 to 7, characterized in that a 1.0 to 10.0% by weight. The resin fine particles, method for producing a toner according to any one of claims 1 to 8, characterized in that the surface of the core particles by coating 90% or more.