JP5506336B2 - Toner and toner production method - Google Patents

Description

  The present invention relates to a toner used in a recording method using electrophotography or the like and a method for producing the toner.

  A pulverization method and a wet method are known as methods for producing toner used in electrophotography. Examples of the method for producing toner particles by a wet method include a suspension polymerization method, an emulsion polymerization method, an emulsion aggregation method, and a dissolution suspension method. Among these, the suspension polymerization method is a monomer composition in which a polymerizable monomer, a colorant, a polymerization initiator and, if necessary, a crosslinking agent, a charge control agent, and other additives are uniformly dissolved or dispersed. Is made. Thereafter, the monomer composition is dispersed in a continuous phase containing a dispersion stabilizer, such as an aqueous phase, using an appropriate stirrer, and simultaneously polymerized to obtain toner particles, which is relatively easy. In this method, toner particles having a sharp particle size distribution and a high circularity can be obtained.

  Toner having a high degree of circularity develops an electrostatic latent image on a photoreceptor faithfully and accurately, and exhibits high transferability, so that it has a tremendous effect on image quality and resolution. On the other hand, there is a drawback that the cleaning property tends to be lowered and problems such as defective cleaning tend to occur during a printing test in a copying machine or a printer. In response to this problem, many proposals for improvement by selection of external additives and external addition conditions have been made and are described in Patent Documents 1 and 2.

  On the other hand, it is considered possible to improve the cleaning property by controlling the fine structure on the surface of the toner particles so as to be easily scraped off by the cleaning blade while maintaining high circularity. In the production of toner particles by suspension polymerization, several inventions for controlling the surface properties of toner particles have been proposed. Patent Document 3 proposes a method for controlling the surface structure of toner particles that can improve anti-blocking properties by adding an oil-soluble initiator and a water-soluble initiator in two stages and forming a polymer film on the toner particle surface. doing. Patent Document 4 proposes a method for controlling the surface structure of toner particles that suppresses bleeding of a release agent by forming a polymer film on the surface of toner particles using a redox polymerization method. However, in these proposals, there is no description about the improvement effect on the cleaning property.

  Such a structure control method is a structure control related to the material composition in the vicinity of the toner particle surface, and is not a shape control. Therefore, it is presumed that the toner particle surface property necessary for improving the cleaning property is not provided. That is, in the suspension polymerization method, there is still room for study on the method of controlling the toner particle surface structure that can improve the cleaning property.

JP 2000-081723 A JP2004-037603 JP-A-11-160909 JP-A-11-202553

  An object of the present invention is to provide a toner and a method for producing toner particles that solve the above-mentioned problems.

  That is, an object of the present invention is to provide a toner and a method for producing toner particles having improved cleaning properties in the suspension polymerization method. It is another object of the present invention to provide a toner having good low-temperature fixability and a method for producing toner particles.

The present invention is a polymerizable monomer composition having containing a polymerizable monomer and a colorant is added to the aqueous medium, in aqueous medium to form particles of the polymerizable monomer composition, the the polymerizable monomer contained in the particles of the polymerizable monomer composition with a polymerization initiator to polymerize obtain toner particles, a process for the preparation of toner particles,
The polymerization initiator, was added in several times,
Polymerization initiator A added to the first-time, those selected from the group consisting of peroxydicarbonate and diacyl peroxide,
A polymerization initiator B was added when the polymerization conversion reached below 99.5% 60.0%,
The polymerization initiator B is a water-soluble polymerization initiator,
Polymerization initiator 10-hour half-life was measured using a toluene A temperature T (A) (℃) is, and at 40 ° C. or higher 62 ° C. or less,
During the period from the addition of the polymerization initiator A to addition of polymerization initiator B, keeping the temperature T of the aqueous medium so as to satisfy the following equation 1 (JA) (℃) (Equation 1) T (A ) + 25 ≦ T (JA) ≦ T (A) +36
The present invention relates to a method for producing toner particles.

  By devising the addition of the polymerization initiator in the suspension polymerization method, a toner having good low-temperature fixability and improved cleaning properties can be obtained.

FIG. 2 is a schematic cross-sectional view illustrating an example of an image forming apparatus that can suitably use the toner of the present invention.

As a result of intensive studies by the present inventors, in a method for producing toner particles by a suspension polymerization method,
(1) A polymerization initiator is added a plurality of times,
(2) The polymerization initiator A added for the first time is selected from peroxydicarbonate and diacyl peroxide,
(3) The polymerization initiator B is added when the polymerization conversion rate reaches 60.0% or more and 99.5% or less,
(4) The polymerization initiator B is a water-soluble polymerization initiator,
(5) The 10-hour half-life temperature T (A) (° C.) measured using toluene of the polymerization initiator A is 40 ° C. or more and 62 ° C. or less,
(6) The temperature T (JA) (° C.) and T (A) of the aqueous medium from the addition of the polymerization initiator A to the addition of the polymerization initiator B satisfy the following formula 1 to perform cleaning. The present inventors have found that toner particles having extremely high properties can be obtained and low molecular weight toner particles effective for low-temperature fixability can be obtained.
(Formula 1) T (A) + 25 ≦ T (JA) ≦ T (A) +36

  The present inventors consider the reason why toner particles having high cleaning performance can be obtained as follows.

  The toner particles obtained by the present invention have an uneven shape on the surface, and it is presumed that this surface structure is a key technology that can greatly improve the cleaning property. The mechanism for forming the surface structure of the irregularities is currently under investigation, and the presumed mechanism estimated from them is described below.

  Briefly speaking, this mechanism is considered to be formed by a process such as “surface deformation due to distortion of the toner particle surface due to initiation of the polymerization reaction from the inside and outside of the toner particle”.

  Only when peroxydicarbonate or diacyl peroxide is used as the polymerization initiator A, toner particles having an uneven shape on the surface can be obtained. Since these polymerization initiators have high stability to water and may generate the original polymerization initiator A by a termination reaction, there are many polymerization initiators A inside the toner particles even when the polymerization process has progressed to some extent. It has the characteristic of remaining easily.

  The polymerization initiator B added when the polymerization conversion rate is 60.0% or more and 95.5% or less can obtain uneven toner particles only when a water-soluble initiator is used. In the suspension polymerization method, when a water-soluble initiator is used, the water-soluble initiator does not penetrate into the toner particles and induces a polymerization reaction from the toner particle surfaces. As a result, the polymerization reaction proceeds from the inside of the toner particles by the remaining polymerization initiator A, and at the same time, the polymerization reaction occurs from the vicinity of the surface by the polymerization initiator B. It has been found that the formation of irregularities occurs from the stage when the polymerization initiator B is added. Therefore, since the polymerization reaction proceeds from the inside and outside of the toner particles, the surface of the toner particles is distorted. As a result, it is assumed that toner particles having irregularities on the surface are obtained. On the other hand, when an oil-soluble polymerization initiator is used as the polymerization initiator B, since the polymerization reaction from the vicinity of the surface is not sufficient, toner particles having irregularities cannot be obtained, and as a result, the cleaning property is improved. difficult.

  The polymerization initiator B needs to be added when the polymerization conversion rate is 60.0% or more and 99.5% or less. When the polymerization conversion rate is less than 60.0%, since there are many polymerizable monomers in the toner particles, there is a high possibility of alleviating the distortion generated on the toner surface. Formation does not occur. On the other hand, when the polymerization conversion rate is higher than 95.5%, since many polymerizable monomers are fixed as the binder resin, the deformation of the shape does not occur. Further, if any initiator is not added before the polymerization conversion rate reaches 100%, toner particles having irregularities cannot be obtained. Thus, by using the water-soluble polymerization initiator B when the polymerization conversion rate is 60.0% or more and 95.5% or less, the toner particle surface has a concavo-convex shape, and the cleaning property is greatly improved. Particles can be obtained.

  In order to obtain uneven toner particles, it is necessary that the polymerization initiator A remains in the toner particles to some extent when the polymerization initiator B is added. The amount of the remaining polymerization initiator A can be controlled by the 10-hour half-life temperature T (A) measured using toluene and the relationship between T (A) and the polymerization temperature T (JA). When T (JA) is higher than T (A) + 36 ° C., the decomposition rate and deactivation rate of the polymerization initiator A are high, and the amount of the polymerization initiator A remaining inside the toner particles when the polymerization initiator B is added. As a result, toner particles having irregularities cannot be obtained. On the other hand, when T (JA) is less than T (A) + 25 ° C., the radical concentration in the system is low, and the binder resin formed from the polymerizable monomer has a relatively high molecular weight, so that deformation is unlikely to occur. It is considered that the toner particle surface does not change in shape, and as a result, uneven toner particles cannot be obtained.

  As described above, the uneven shape formed on the surface of the toner particles can be controlled by keeping T (A) and the relationship between T (A) and T (JA) within an appropriate range.

  Therefore, it is considered that the toner particles produced according to the present invention have irregularities on the particle surface and can greatly improve the cleaning property.

  The toner particles obtained by the production method of the present invention have good low-temperature fixability because the weight average molecular weight Mw of the binder resin is relatively small in addition to the improvement in cleaning properties. In general, it is known that when the molecular weight distribution of the binder resin tends to be low molecular weight, it has excellent low-temperature fixability. Here, the tendency of the molecular weight distribution to be low in molecular weight often means that the peak molecular weight Mp and the weight average molecular weight Mw are small. Since the polymerization initiator used in the present invention is peroxydicarbonate or diacyl peroxide, the stability to water is high, so the possibility of deactivation is low, and as a result, the amount of effective radical generation is large. In addition, as shown in Formula 1, the polymerization reaction proceeds at a temperature relatively higher than the half-life temperature of the polymerization initiator, so that the effective radical generation amount tends to be further increased. In addition, since the polymerization initiator remains in the latter half of the polymerization reaction, the possibility that the remaining polymerizable monomer is used for further growth of the high molecular weight material is reduced, and the weight average molecular weight Mw of the binder resin is increased. Hateful. That is, the toner particles obtained according to the present invention have good low-temperature fixability because the weight average molecular weight Mw of the binder resin is small for the reasons described above.

  Here, the peak molecular weight Mp means a value obtained by measuring tetrahydrofuran (THF) soluble content by gel permeation chromatography (GPC). Moreover, the weight average molecular weight Mw means the value obtained by measuring tetrahydrofuran (THF) soluble content by size exclusion chromatography online-multi-angle light scattering (SEC-MALLS). Mp employs GPC as an analyzer from the viewpoint of versatility. Moreover, Mw employs SEC-MALLS, which is easy to reflect the amount of high molecular weight and excellent in detection of high molecular weight, as an analyzer. These analysis methods will be described later.

  It is preferable that the polymerization initiator A is 1.0 part by mass or more and 10.0 parts by mass or less with respect to 100 parts by mass of the polymerizable monomer. It has been found that the degree of unevenness formed on the toner particle surface is affected by the molecular weight of the binder resin. Specifically, when the molecular weight of the binder resin is too low, the generated distortion is easily relieved, and when it is too high, unevenness is hardly formed on the toner particle surface even if the distortion occurs. When the amount of the polymerization initiator A is included in this range, the molecular weight of the binder resin when the polymerization initiator B is added tends to be in an appropriate range, and the toner particle surface can be effectively deformed. As a result, it is possible to provide toner particles with further improved cleaning properties. On the other hand, when the amount is 1.0 part by mass or more, the peak molecular weight Mp and the weight average molecular weight Mw of the binder resin are small, and the low-temperature fixability is excellent and the toner performance is further improved. When the amount is 10.0 parts by mass or less, the chargeability of the toner tends to be good and the image density increases, and as a result, the toner performance is further improved.

  The polymerization initiator B is preferably 0.2 parts by mass or more and 10.0 parts by mass or less with respect to 100 parts by mass of the polymerizable monomer. When the polymerization initiator B is 0.2 parts by mass or more, the toner particle surface can be effectively deformed, and as a result, toner particles with further improved cleaning properties can be provided. On the other hand, when the polymerization initiator B is 10.0 parts by mass or less, a relatively spherical toner can be obtained while forming irregularities on the toner surface, so that toner particles having good transferability can be provided. Therefore, when the polymerization initiator B is 0.2 parts by mass or more and 10.0 parts by mass or less, it is possible to obtain further excellent toner particles with better cleaning properties and better transferability.

The weight-average molecular weight Mw when the tetrahydrofuran-soluble content of the toner particles is measured by size exclusion chromatography online-multi-angle light scattering (SEC-MALLS) is 5000 to 25000, and the weight-average molecular weight Mw and the inertial square radius Rw Preferably satisfies the following formula 2.
(Formula 2) 2.0 × 10 ⁻³ ≦ Rw / Mw ≦ 1.0 × 10 ⁻²

Rw / Mw is an index of the degree of branching of the polymer chain of the binder resin, and the complete linear high molecular weight substance approaches 1. The degree of surface irregularity formation can be controlled by the degree of branching of the binder resin. When Rw / Mw is 2.0 × 10 ⁻³ or more, the deformation of the toner particle surface easily proceeds uniformly at various places, and the degree of unevenness between the toner particles and within the toner particles becomes uniform. As a result, it is possible to provide toner particles having further excellent transferability. On the other hand, when Rw / Mw is 1.0 × 10 ⁻² or less, the degree of unevenness is increased, and toner particles having excellent cleaning properties can be provided. Further, when the Mw is 5000 or more and 25000 or less, the degree of deformation of the toner particle surface is likely to be large, and since the generated distortion is less likely to occur, the degree of unevenness is likely to be large, and the toner particles having excellent cleaning properties Can be provided.

  In the present invention, the radius of inertia square is measured by size exclusion chromatography-online-multi-angle light scattering (SEC-MALLS) for the following reason. The molecular weight distribution measured by SEC is the molecular size and the intensity is its abundance. On the other hand, the light scattering intensity obtained with SEC-MALLS (by combining SEC and a multi-angle light scattering detector as a separation means and measuring the absolute molecular weight and molecular size (square of inertia)) is the molecular size. Increases strength. However, the presence of a peak due to the elution time in SEC-MALLS measurement means that a polymer having a molecular spread (molecular size) at the molecular weight exists with a number distribution.

  In the conventional SEC method, when a molecule to be measured passes through a column, the molecule is subjected to a molecular sieving effect and eluted according to the molecular size, and the molecular weight is measured. In this case, the linear polymer and the branched polymer having the same molecular weight are eluted earlier because the former has a larger molecular size in the solution. Therefore, the molecular weight of the branched polymer measured by the SEC method is measured smaller than the true molecular weight.

  On the other hand, in the light scattering method of the present invention, Rayleigh scattering of the measurement molecule was used.

  Measure the dependence of the incident angle of the light and the sample concentration on the intensity of the scattered light, and analyze it with the Zimm method, the Berry method, etc., and the true molecular weight (absolute molecular weight) can be obtained for all molecular forms of linear polymers and branched polymers. (In the present invention, the absolute molecular weight was calculated by the Zim method by the SEC-MALLS measurement method (described later)). As a result, the molecular design of the toner can be performed precisely.

Rw / Mw as described above represents the degree of branching of the binder resin. When Rw / Mw is low, the degree of branching of the binder resin is high, and when it is high, the degree of branching of the binder resin is low and linear. It is close to a high molecular weight body. For example, in the production method of the present invention, in order to obtain a binder resin having a desired Mw and Rw / Mw, it is necessary to adjust the polymerization conditions and the amount of the polymerization initiator A to be used. Specifically, in the situation where the polymerization reaction by the polymerization initiator A proceeds, the radical concentration generated increases due to the high reaction temperature and the amount of the polymerization initiator A, and the molecular weight of the binder resin decreases. Tend to be. That is, it is possible to reduce Mw. On the other hand, since the binder resin has a branched structure, there are means such as causing a hydrogen abstraction reaction during polymerization and branching by this. The present invention proposes a reaction temperature condition in which the 10-hour half-life temperature T (A) measured using the polymerization initiator A toluene and the reaction temperature T (JA) in the polymerization step satisfy the following formula 1.
(Formula 1) T (A) + 25 ≦ T (JA) ≦ T (A) +36

  Since this temperature range is a temperature relatively higher than the half-life temperature, the frequency of occurrence of hydrogen abstraction is not easily influenced by the reaction temperature, but tends to depend on the amount of the polymerization initiator A used. Therefore, Mw can be adjusted by controlling the reaction temperature T (JA) and the amount of the polymerization initiator A, and Mw / Rw can be adjusted by adjusting the amount of the polymerization initiator A. That is, it is possible to control Mw and Mw / Rw independently.

  The toner of the present invention preferably has an average circularity of 0.960 or more. When the average circularity of the toner is 0.960 or more, the toner has a spherical shape or a shape close to it, and it is easy to obtain a uniform triboelectric chargeability with excellent fluidity. The toner particles produced by the production method of the present invention have irregularities on the particle surface, but the degree of irregularities hardly appears in the average circularity. This is because the degree of unevenness does not have undulations that affect the average circularity. Accordingly, the unevenness greatly improves the cleaning property, and it is possible to achieve both excellent uniform triboelectric charging property due to high circularity.

  The toner particles produced according to the present invention preferably have a weight average particle diameter (D4) of 3.0 μm or more and 9.0 μm or less, and more preferably 4.0 μm or more and 10.0 μm or less. When the weight average particle diameter (D4) is 3.0 μm or more and 12.0 μm or less, good fluidity can be obtained and development can be performed faithfully to the latent image. For this reason, a good image excellent in dot reproducibility can be obtained.

  It is preferable that the toner particles produced according to the present invention have a peak molecular weight (Mp) soluble in tetrahydrofuran (THF) of 4000 or more and 60000 or less.

  When the peak molecular weight (Mp) is 4000 or more and 60000 or less, the plasticity and deformation of the toner at the time of fixing are promoted, and the low-temperature fixing property is improved. Further, since the fixing property in the concave portion is also improved, offset is less likely to occur, which is more preferable. Further, even in the latter half of the durability, it is possible to suppress a decrease in density and an increase in fog due to toner deterioration.

  The toner particles produced according to the present invention preferably have a release agent of 1 part by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the binder resin in order to further improve the fixability. More preferably, the top is 50 ° C. or higher and 90 ° C. or lower. Moreover, if the addition amount of the mold release agent to be added is less than 1 part by mass with respect to 100 parts by mass of the binder resin, the effect of adding the mold release agent becomes low. On the other hand, if the amount exceeds 30 parts by mass, the long-term storage stability is deteriorated, and the toner charging uniformity is deteriorated due to the oozing out to the toner surface, which is not preferable.

  Further, as the releasing agent to be added, known releasing agents can be used, petroleum waxes such as paraffin wax, microcrystalline wax, petrolatum and derivatives thereof, montan wax and derivatives thereof, hydrocarbon waxes by Fischer-Tropsch method, and Derivatives, polyolefin waxes typified by polyethylene and derivatives thereof, natural waxes such as carnauba wax and candelilla wax and derivatives thereof, etc. The derivatives include oxides, block copolymers with vinyl monomers, and graft modified products. Including. Furthermore, fatty acids such as higher aliphatic alcohols, stearic acid and palmitic acid, or compounds thereof, acid amide waxes, ester waxes, ketones, hydrogenated castor oil and derivatives thereof, plant waxes, animal waxes and the like can also be used.

  To the toner particles produced according to the present invention, a charge control agent may be blended as necessary to improve charging characteristics. As the charge control agent, a known one can be used, but a charge control agent that has a high charging speed and can stably maintain a constant charge amount is particularly preferable. Among the charge control agents, specific examples of negative charge control agents include metal compounds of aromatic carboxylic acids such as salicylic acid, alkyl salicylic acid, dialkyl salicylic acid, naphthoic acid, dicarboxylic acid, azo dyes or metal salts of azo pigments or Examples thereof include a metal complex, 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 the positive charge control agent include a quaternary ammonium salt, a polymer compound having the quaternary ammonium salt in the side chain, a guanidine compound, a nigrosine compound, and an imidazole compound.

  In the production method of the present invention, as a method of incorporating a charge control agent into the toner, a method of adding the charge control agent to the polymerizable monomer composition before granulation is general. Also, during the polymerization by forming oil droplets in water, or after polymerization, seed polymerization is carried out by adding a polymerizable monomer in which the charge control agent is dissolved and suspended, and the toner surface is made uniform. It is also possible to cover.

  The amount of these charge control agents used 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. However, when added internally to the toner particles, it is preferably 0.1 parts by weight or more and 10.0 parts by weight or less, more preferably 0.1 parts by weight or more and 5.0 parts by weight or less with respect to 100 parts by weight of the binder resin. Used in a range. Further, when externally added to the toner particles, the amount is preferably 0.005 parts by mass or more and 1.000 parts by mass or less, more preferably 0.01 parts by mass or more and 0.30 parts by mass or less with respect to 100 parts by mass of the toner.

  The toner particles produced according to the present invention contain a colorant that matches the target color. As the colorant used in the toner particles produced according to the present invention, any of known organic pigments or dyes, carbon black, magnetic materials and the like can be used.

  Specifically, copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, basic dye lake compounds, and the like can be used as cyan colorants. Specifically, C.I. I. Pigment blue 1, C.I. I. Pigment blue 7, C.I. I. Pigment blue 15, C.I. I. Pigment blue 15: 1, C.I. I. Pigment blue 15: 2, C.I. I. Pigment blue 15: 3, C.I. I. Pigment blue 15: 4, C.I. I. Pigment blue 60, C.I. I. Pigment blue 62, C.I. I. And CI Pigment Blue 66.

  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, C.I. I. Pigment Red 3, C.I. I. Pigment Red 5, C.I. I. Pigment Red 6, C.I. I. Pigment red 7, C.I. I. Pigment violet 19, C.I. I. Pigment red 23, C.I. I. Pigment red 48: 2, C.I. I. Pigment red 48: 3, C.I. I. Pigment red 48: 4, C.I. I. Pigment red 57: 1, C.I. I. Pigment red 81: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 144, C.I. I. Pigment red 146, C.I. I. Pigment red 166, C.I. I. Pigment red 169, C.I. I. Pigment red 177, C.I. I. Pigment red 184, C.I. I. Pigment red 185, C.I. I. Pigment red 202, C.I. I. Pigment red 206, C.I. I. Pigment red 220, C.I. I. Pigment red 221, C.I. I. And CI Pigment Red 254.

  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, C.I. I. Pigment yellow 13, C.I. I. Pigment yellow 14, C.I. I. Pigment yellow 15, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 62, C.I. I. Pigment yellow 74, C.I. I. Pigment yellow 83, C.I. I. Pigment yellow 93, C.I. I. Pigment yellow 94, C.I. I. Pigment yellow 95, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 109, C.I. I. Pigment yellow 110, C.I. I. Pigment yellow 111, C.I. I. Pigment yellow 120, C.I. I. Pigment yellow 127, C.I. I. Pigment yellow 128, C.I. I. Pigment yellow 129, C.I. I. Pigment yellow 147, C.I. I. Pigment yellow 151, C.I. I. Pigment yellow 154, C.I. I. Pigment yellow 155, C.I. I. Pigment yellow 168, C.I. I. Pigment yellow 174, C.I. I. Pigment yellow 175, C.I. I. Pigment yellow 176, C.I. I. Pigment yellow 180, C.I. I. Pigment yellow 181, C.I. I. Pigment yellow 191, C.I. I. And CI Pigment Yellow 194.

  These colorants can be used singly or in combination of two or more, and also in a solid solution state. The colorant used in the toner particles produced according to the present invention is appropriately selected from the viewpoints of hue angle, saturation, brightness, light resistance, OHP transparency, and dispersibility in toner particles. Further, the addition amount of the colorant is preferably 1.0 part by mass or more and 20.0 parts by mass or less with respect to 100 parts by mass of the binder resin.

  Further, as the black colorant, carbon black, a magnetic material, and a color toned to black using the yellow / magenta / cyan colorant are used. When carbon black is used as the black colorant, the amount added is preferably 1.0 parts by mass or more and 20.0 parts by mass or less with respect to 100 parts by mass of the binder resin.

  Further, when the toner particles produced according to the present invention are used as a magnetic toner, a magnetic material can be used as a colorant. When a magnetic material is used as the black colorant, the magnetic material is preferably 20.0 parts by mass or more and 150.0 parts by mass or less with respect to 100 parts by mass of the binder resin. When the added amount of the magnetic material is less than 20.0 parts by mass, the fixability is improved, but the coloring power of the toner is poor and fogging is difficult to suppress. On the other hand, if the amount exceeds 150.0 parts by mass, the fixability is deteriorated and the holding force by the magnetic force of the toner carrier is increased, so that the developability may be deteriorated.

  The content of the magnetic substance in the toner particles can be measured using a thermal analysis device manufactured by PerkinElmer, TGA7. The measuring method is as follows. The toner is heated from room temperature to 900 ° C. at a temperature rising rate of 25 ° C./min in a nitrogen atmosphere. The weight loss mass% between 100 ° C. and 750 ° C. is defined as the binder resin amount, and the remaining mass is approximately defined as the magnetic material amount.

  In the present invention, it is necessary to pay attention to the polymerization inhibitory property and water phase transferability of the colorant. Therefore, the colorant should be subjected to surface modification, for example, a hydrophobic treatment with a substance that does not inhibit polymerization. In particular, since dyes and carbon black have many polymerization-inhibiting properties, care must be taken when using them. About carbon black, you may process with the substance which reacts with the surface functional group of carbon black, for example, polyorganosiloxane.

When a magnetic material is used for the toner particles produced according to the present invention, the magnetic material is mainly composed of magnetic iron oxide such as triiron tetroxide and γ-iron oxide, and phosphorus, cobalt, nickel, copper, Elements such as magnesium, manganese, aluminum, and silicon may be included. These magnetic materials preferably have a BET specific surface area of 2.0 m ² / g or more and 30.0 m ² / g or less, and 3.0 m ² / g or more and 28.0 m ² / g or less by the nitrogen adsorption method. Is more preferable.

  The shape of the magnetic body includes a polyhedron, an octahedron, a hexahedron, a sphere, a needle, and a scale, but a polyhedron, an octahedron, a hexahedron, a sphere, and the like having a low anisotropy increase the image density. Preferred above.

  The magnetic material preferably has a volume average particle diameter (D3) of 0.10 μm or more and 0.40 μm or less. Generally, the smaller the particle size of the magnetic material, the higher the coloring power, but the magnetic material tends to aggregate and the uniform dispersibility of the magnetic material in the toner tends to be poor. In addition, when the volume average particle diameter (D3) is less than 0.10 μm, the magnetic substance itself becomes reddish black, so that it tends to be a reddish conspicuous image particularly in a halftone image. On the other hand, if the volume average particle size (D3) is larger than 0.40 μm, the coloring power of the toner is insufficient, and uniform dispersion tends to be difficult in the suspension polymerization method (described later) which is a method for producing toner particles of the present invention. It is in.

  In addition, the volume average particle diameter (D3) of a magnetic body can be measured using a transmission electron microscope. Specifically, after sufficiently dispersing the toner particles to be observed in the epoxy resin, a cured product obtained by curing in an atmosphere at a temperature of 40 ° C. for 2 days is obtained. The obtained cured product is used as a flaky sample by a microtome, and the diameter of 100 magnetic particles in the field of view is measured with a transmission electron microscope (TEM) at a magnification of 10,000 to 40,000 times. Then, the volume average particle diameter (D3) is calculated based on the equivalent diameter of a circle equal to the projected area of the magnetic material. It is also possible to measure the particle size with an image analyzer.

  The magnetic material used for the toner particles produced according to the present invention can be produced, for example, by the following method. An aqueous solution containing ferrous hydroxide is prepared by adding an alkali such as sodium hydroxide in an amount equivalent to or greater than the iron component to the ferrous salt aqueous solution. Air was blown in while maintaining the pH of the prepared aqueous solution at 7.0 or higher, and ferrous hydroxide was oxidized while heating the aqueous solution to 70 ° C. or higher, and seed crystals serving as the core of the magnetic iron oxide particles were formed. First generate.

  Next, an aqueous solution containing about 1 equivalent of ferrous sulfate is added to the slurry-like liquid containing seed crystals based on the amount of alkali added previously. The pH of the liquid is maintained at 5.0 or higher and 10.0 or lower, and the reaction of ferrous hydroxide proceeds while blowing air, and magnetic iron oxide particles are grown with the seed crystal as a core. At this time, it is possible to control the shape and magnetic characteristics of the magnetic material by selecting an arbitrary pH, reaction temperature, and stirring conditions. As the oxidation reaction proceeds, the pH of the liquid shifts to the acidic side, but the pH of the liquid is preferably not less than 5.0. A magnetic material can be obtained by filtering, washing, and drying the magnetic material thus obtained by a conventional method.

  Further, in the toner particles produced according to the present invention, when a magnetic material is used as a colorant, it is very preferable to subject the surface of the magnetic material to a hydrophobic treatment. When the hydrophobizing treatment is performed by a dry method, the hydrophobizing treatment is performed on the washed, filtered and dried magnetic material using a coupling agent. When the hydrophobization treatment is performed in a wet manner, after the oxidation reaction is completed, the dried material is redispersed, or after the oxidation reaction is completed, the iron oxide body obtained by washing and filtering is not dried and another aqueous medium is used. It is redispersed in and hydrophobized. Specifically, the hydrophobization treatment is performed by adding a coupling agent while sufficiently stirring the re-dispersed liquid to increase the temperature after hydrolysis, or adjusting the pH of the dispersion to an alkaline region after hydrolysis. Among these, from the viewpoint of carrying out a uniform hydrophobization treatment, it is preferable to carry out the hydrophobization treatment after completion of the oxidation reaction, by reslurry as it is without drying after filtration and washing.

  To hydrophobize a magnetic material, that is, in order to treat the magnetic material with a coupling agent in an aqueous medium, first, sufficiently disperse the magnetic substance in the aqueous medium so as to have a primary particle size, and do not settle or aggregate. Stir with a stirring blade or the like. Next, an arbitrary amount of coupling agent is added to the above dispersion, and the coupling agent is hydrophobized while hydrolyzing, but at this time it is sufficient to avoid aggregation while using a device such as a pin mill or a line mill while stirring. It is more preferable to perform the hydrophobizing treatment while dispersing.

  Here, the aqueous medium is a medium containing water as a main component. Specific examples include water itself, water added with a small amount of surfactant, water added with a pH adjusting agent, and water added with an organic solvent. As the surfactant, nonionic surfactants such as polyvinyl alcohol are preferable. The addition amount of the surfactant is preferably 0.1 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of water. Examples of the pH adjuster include inorganic acids such as hydrochloric acid. Examples of the organic solvent include alcohols.

Examples of the coupling agent that can be used for the hydrophobic treatment of the magnetic material include a silane coupling agent and a titanium coupling agent. More preferably used are silane coupling agents, which are represented by the general formula (1).
R _m SiY _n (1)
[Wherein, R represents an alkoxy group, m represents an integer of 1 to 3, Y represents a functional group such as an alkyl group, a vinyl group, an epoxy group, or a (meth) acryl group, and n represents 1 to 3] Indicates an integer. However, m + n = 4. ]

  Examples of the silane coupling agent represented by the general formula (1) include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, Vinyltriacetoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, diphenyl Diethoxysilane, n-butyltrimethoxysilane, isobutyltrimethoxysilane, trimethylmethoxysilane, n-hexyltrimethoxysilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, n-decyltrimethoxysilane, hydroxypropyl Examples include trimethoxysilane, n-hexadecyltrimethoxysilane, and n-octadecyltrimethoxysilane.

Among these, from the viewpoint of imparting high hydrophobicity to the magnetic material, it is preferable to use an alkyltrialkoxysilane coupling agent represented by the following general formula (2).
_{C p H 2p + 1 -Si- (} OC q H 2q + 1) 3 (2)
[Wherein, p represents an integer of 2 to 20, and q represents an integer of 1 to 3. ]

  When p in the above formula is smaller than 2, it is difficult to sufficiently impart hydrophobicity to the magnetic material. When p is larger than 20, hydrophobicity is sufficient, but the coalescence between the magnetic materials increases. It is not preferable. Furthermore, when q is larger than 3, the reactivity of the silane coupling agent is lowered and it becomes difficult to sufficiently perform hydrophobicity. Accordingly, in the formula, p represents an integer of 2 to 20 (more preferably, an integer of 3 to 15), and q represents an integer of 1 to 3 (more preferably, an integer of 1 or 2). It is preferable to use a coupling agent.

  When using the said silane coupling agent, it is possible to process independently or to process in combination of several types. When using several types together, you may process separately with each coupling agent, and may process simultaneously.

  The total amount of coupling agent used is preferably 0.5 to 3.0 parts by mass with respect to 100 parts by mass of the magnetic material, depending on the surface area of the magnetic material, the reactivity of the coupling agent, etc. It is important to adjust the amount of treatment agent.

  In the toner particles produced according to the present invention, other colorants may be used in combination with the magnetic material. Examples of the colorant that can be used in combination include magnetic or nonmagnetic inorganic compounds in addition to the above-described known dyes and pigments. Specifically, ferromagnetic metal particles such as cobalt and nickel, or alloys obtained by adding chromium, manganese, copper, zinc, aluminum, rare earth elements and the like to these. Examples thereof include particles such as hematite, titanium black, nigrosine dye / pigment, carbon black, and phthalocyanine. These are also preferably used by treating the surface.

  The toner particles produced according to the present invention preferably have a glass transition temperature (Tg) of 40.0 ° C. or higher and 70.0 ° C. or lower. When the glass transition temperature is less than 40.0 ° C., the storage stability is lowered, and the toner is liable to deteriorate during long-term use. When the glass transition temperature is higher than 70.0 ° C., the fixing property is deteriorated. Therefore, considering the balance between fixability, storage stability, and developability, the glass transition temperature of the toner is preferably 40.0 ° C. or higher and 70.0 ° C. or lower.

  When a shell layer is applied to the toner particles produced according to the present invention, the shell layer described below is preferable in order not to impair the effects of the present invention.

  The toner particles produced according to the present invention preferably have a core-shell structure in order to improve storage stability and developability. This is because by having the shell layer, the surface property of the toner becomes uniform, the fluidity improves and the charging property becomes uniform.

  Further, since the high molecular weight shell uniformly covers the surface layer, the low-melting-point substance does not easily leach out even during long-term storage, and the storage stability is improved.

  For this reason, it is preferable to use an amorphous high molecular weight material for the shell layer, and from the viewpoint of charging stability, the acid value is preferably 5.0 mgKOH / g or more and 20.0 mgKOH / g or less.

  As a specific method of forming the shell, the shell layer is formed by embedding the fine particles for the shell in the core particles, or by attaching the fine particles for the shell to the core particles and drying the toner in an aqueous medium. It is possible to make it.

  The toner particles produced according to the present invention utilize the hydrophilicity of the high molecular weight material for the shell in the suspension polymerization method, and the high molecular weight material is unevenly distributed at the interface with water, that is, near the toner surface to form a shell. Is possible. Furthermore, a shell can be formed by swelling a monomer on the surface of the core particle by a so-called seed polymerization method and polymerizing the monomer.

  Examples of the high molecular weight body for the shell layer include styrene such as polystyrene and polyvinyltoluene and homopolymers thereof, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, Styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-dimethylaminoethyl acrylate copolymer, styrene-methacrylic acid Acid methyl copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-dimethylaminoethyl methacrylate copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer Polymer, styrene-vinyl Styrene copolymers such as methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester copolymer, polymethyl methacrylate, polybutyl methacrylate , Polyvinyl acetate, polyethylene, polypropylene, polyvinyl butyral, silicone resin, polyester resin, styrene-polyester copolymer, poly (meth) acrylate-polyester copolymer, polyamide resin, epoxy resin, polyacrylic acid resin, terpene resin, There are phenol resins and the like, and these can be used alone or in admixture of two or more. Moreover, you may introduce | transduce functional groups, such as an amino group, a carboxyl group, a hydroxyl group, a sulfonic acid group, a glycidyl group, a nitrile group, in these polymers.

  As addition amount of these resin, it is preferable that they are 1.0 mass part or more and 30.0 mass parts or less in total with respect to 100 mass parts of polymerizable monomers.

  Among these resins, polyester is particularly preferable because the above effect is greatly expressed. As the polyester resin used in the present invention, a saturated polyester resin, an unsaturated polyester resin, or both can be appropriately selected and used.

  As the polyester resin used in the present invention, a normal resin composed of an alcohol component and an acid component can be used, and both components are exemplified below.

  As alcohol components, ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1,6-hexane Examples include diol, neopentyl glycol, 2-ethyl-1,3-hexanediol, cyclohexanedimethanol, butenediol, octenediol, cyclohexenedimethanol, hydrogenated bisphenol A, and bisphenol derivatives.

  As the divalent carboxylic acid, benzene dicarboxylic acid such as phthalic acid, terephthalic acid, isophthalic acid, phthalic anhydride or its anhydride, alkyl dicarboxylic acid such as succinic acid, adipic acid, sebacic acid, azelaic acid or its anhydride, Furthermore, succinic acid substituted with an alkyl or alkenyl group having 6 to 18 carbon atoms or an anhydride thereof, unsaturated dicarboxylic acid such as fumaric acid, maleic acid, citraconic acid, itaconic acid or the anhydride thereof may be mentioned.

  Furthermore, polyhydric alcohols such as glycerin, pentaerythritol, sorbit, sorbitan, and oxyalkylene ethers of novolak type phenol resins can be cited as polyhydric alcohol components. Trimellitic acid, pyromellitic acid, 1, 2, Examples include polyvalent carboxylic acids such as 3,4-butanetetracarboxylic acid, benzophenonetetracarboxylic acid, and anhydrides thereof.

  Among the polyester resins, the alkylene oxide adduct of bisphenol A, which is excellent in charging characteristics and environmental stability and balanced in other electrophotographic characteristics, is preferably used. In the case of this compound, the average number of added moles of alkylene oxide is preferably 2.0 mol or more and 10.0 mol or less in terms of fixability and toner durability.

  The number average molecular weight (Mn) of the high molecular weight body forming the shell is preferably 2500 or more and 20000 or less. When the number average molecular weight (Mn) is less than 2500, developability, blocking resistance, and durability tend to deteriorate. On the other hand, when the number average molecular weight (Mn) exceeds 20000, the developability and durability are improved, but the low-temperature fixability is easily inhibited. The number average molecular weight (Mn) can be measured by GPC.

  The suspension polymerization method is described below.

  The suspension polymerization method is a polymerizable monomer in which a polymerizable monomer and a colorant (in addition, a polymerization initiator, a crosslinking agent, a charge control agent, and other additives as necessary) are uniformly dissolved or dispersed. A composition is obtained. Thereafter, the polymerizable monomer composition is dispersed in a continuous layer (for example, an aqueous phase) containing a dispersion stabilizer by using a suitable stirrer, and a polymerization reaction is simultaneously performed to obtain a toner having a desired particle size. To get. Since the toner obtained by this suspension polymerization method (hereinafter also referred to as “polymerized toner”) has individual toner particle shapes that are substantially spherical, the physical property requirement suitable for the present invention that the average circularity is 0.960 or more. It is easy to obtain a toner that satisfies the requirements. Furthermore, since the toner has a relatively uniform charge amount distribution, an improvement in image quality can be expected.

  In the production of the polymerized toner according to the present invention, examples of the polymerizable monomer constituting the polymerizable monomer composition include the following.

  Examples of the polymerizable monomer include styrene monomers such as styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-ethylstyrene, methyl acrylate, ethyl acrylate, Acrylate esters such as n-butyl acrylate, isobutyl acrylate, n-propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, and phenyl acrylate , Methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, Methacrylic acid dimethyl aminoethyl, methacrylic acid esters such as diethylaminoethyl methacrylate and other acrylonitrile, methacrylonitrile, and the like monomers acrylamide. These monomers can be used alone or in combination. Among the above-mentioned monomers, styrene or a styrene derivative is preferably used alone or mixed with other monomers from the viewpoint of developing characteristics and durability of the toner.

  In the method for producing toner particles of the present invention, a polymerization initiator is added a plurality of times.

  As the polymerization initiator A added for the first time in the method for producing toner particles of the present invention, a peroxydicarbonate-based polymerization initiator or a diacyl peroxide-based polymerization initiator can be used.

  Specific examples of the polymerization initiator A include peroxy such as diisopropyl peroxydicarbonate, di-n-peroxydicarbonate, di-sec-butyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate, and the like. Examples include diacyl peroxide polymerization initiators such as dicarbonate polymerization initiators, dilauroyl peroxide, and dibenzoyl peroxide.

  In the method for producing toner particles of the present invention, as the water-soluble polymerization initiator B added at a polymerization conversion rate of 60.0% or more and 95.5% or less, ammonium persulfate, potassium persulfate, 2,2′- Azobis (N, N'-dimethyleneisobutyroamidine) hydrochloride, 2,2'-azobis (2-aminodinopropane) hydrochloride, azobis (isobutylamidine) hydrochloride, 2,2'-azobisisobuty Examples include sodium nitrile sulfonate, ferrous sulfate or hydrogen peroxide.

  A crosslinking agent may be added to the method for producing toner particles of the present invention, and a preferable addition amount is 0.01 parts by mass or more and 10.00 parts by mass or less with respect to 100 parts by mass of the polymerizable monomer. .

  Here, as the crosslinking agent, 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 diacrylate. Carboxylic acid ester having two double bonds, such as methacrylate, 1,3-butanediol dimethacrylate, divinyl compounds such as divinylaniline, divinyl ether, divinyl sulfide, divinyl sulfone, and three or more vinyl groups A compound is used alone or as a mixture of two or more.

  In the method for producing toner particles of the present invention, a polymerizable monomer composition which is generally dissolved or dispersed uniformly by a dispersing machine such as a homogenizer, a ball mill, an ultrasonic dispersing machine or the like by adding the above-described toner composition or the like as appropriate. The product is suspended in an aqueous medium containing a dispersion stabilizer. At this time, the particle size of the obtained toner particles becomes sharper by using a high-speed disperser such as a high-speed stirrer or an ultrasonic disperser to obtain a desired toner particle size at a stretch. As the timing of adding the polymerization initiator A added for the first time, it may be added at the same time when other additives are added to the polymerizable monomer, or may be mixed immediately before being suspended in the aqueous medium. good. Also, a polymerization initiator dissolved in a polymerizable monomer or solvent can be added immediately after granulation and before starting the polymerization reaction.

  After granulation, stirring may be performed using a normal stirrer to such an extent that the particle state is maintained and particle floating and sedimentation are prevented.

  In the method for producing toner particles of the present invention, a known surfactant, organic dispersant or inorganic dispersant can be used as a dispersion stabilizer. In particular, inorganic dispersants are less likely to produce harmful ultrafine powders, and because of their steric hindrance, dispersion stability is obtained, so even if the reaction temperature is changed, stability is not easily lost, and washing is easy and does not adversely affect the toner. Therefore, it can be preferably used. Examples of such inorganic dispersants include tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, phosphate polyvalent metal salts such as hydroxyapatite, carbonates such as calcium carbonate and magnesium carbonate, calcium metasuccinate, calcium sulfate, Examples thereof include inorganic salts such as barium sulfate and inorganic compounds such as calcium hydroxide, magnesium hydroxide, and aluminum hydroxide.

  These inorganic dispersants are preferably used in an amount of 0.20 parts by mass or more and 20.00 parts by mass or less with respect to 100 parts by mass of the polymerizable monomer. Moreover, the said dispersion stabilizer may be used independently and may use multiple types together. Furthermore, you may use together 0.0001 mass part or more and 0.1000 mass part or less surfactant with respect to 100 mass parts of polymerizable monomers.

  When these inorganic dispersants are used, they may be used as they are, but in order to obtain finer particles, the inorganic dispersant particles can be generated and used in an aqueous medium. For example, in the case of tricalcium phosphate, a sodium phosphate aqueous solution and a calcium chloride aqueous solution can be mixed under high-speed stirring to produce water-insoluble calcium phosphate, which enables more uniform and fine dispersion. At the same time, water-soluble sodium chloride salt is produced as a by-product. However, if water-soluble salt is present in the aqueous medium, dissolution of the polymerizable monomer in water is suppressed, and ultrafine toner is generated by emulsion polymerization. This is more convenient.

  Examples of the surfactant include sodium dodecylbenzene sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, sodium stearate, potassium stearate and the like.

Further, in the present invention, a 10-hour half-life temperature T (A) (° C.) measured using toluene of the polymerization initiator A and an aqueous system from the addition of the polymerization initiator A to the addition of the polymerization initiator B It is necessary to set the temperature T (JA) as the reaction temperature so that the temperature T (JA) (° C.) of the medium satisfies the following formula 1.
(Formula 1) T (A) + 25 ≦ T (JA) ≦ T (A) +36

  Here, the temperature T (JA) of the aqueous medium indicates a temperature corresponding to the actual reaction temperature, and does not include a temperature range associated with a temperature change such as a temperature increase to a predetermined temperature.

  After the polymerization of the polymerizable monomer is completed, the obtained polymer particles are filtered, washed and dried by a known method to obtain toner particles. A toner can be obtained by mixing the toner particles with inorganic fine powder as described later as necessary and adhering them to the surface of the toner particles. It is also possible to insert a classification step in the manufacturing process (before mixing the inorganic fine powder) to cut coarse powder and fine powder contained in the toner particles.

  The toner particles produced according to the present invention are preferably mixed with inorganic fine powder as necessary to adhere to the surface of the toner particles.

  The inorganic fine powder preferably has a number average primary particle size (D1) of 4 nm to 80 nm, more preferably 6 nm to 40 nm.

  When the number average primary particle size (D1) of the inorganic fine powder is 4 nm or more and 80 nm or less, the fluidity of the toner is excellent, and uniform chargeability can be obtained, and a uniform image can be obtained even in long-term use. I can get it.

  The number average primary particle diameter (D1) of the inorganic fine powder is measured using a photograph of the toner magnified by a scanning electron microscope.

Silica, titanium oxide, alumina, etc. can be used as the inorganic fine powder used in the present invention. As the fine silica powder, for example, both a so-called dry method produced by vapor phase oxidation of silicon halide or dry silica called fumed silica, and so-called wet silica produced from water glass or the like can be used. is there. However, dry silica having fewer silanol groups on the surface and in the silica fine powder and less production residue such as Na ₂ O and SO ₃ ²⁻ is more preferable. In dry silica, it is also possible to obtain a composite fine powder of silica and other metal oxides by using other metal halogen compounds such as aluminum chloride and titanium chloride together with silicon halogen compounds in the production process, They are also included.

  The amount of the inorganic fine powder used in the toner particles produced according to the present invention is preferably 0.1 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the toner particles. The addition amount of the inorganic fine powder is preferably in the above range since the toner can be given good fluidity and the fixing property is not hindered.

  The content of the inorganic fine powder can be quantified using a calibration curve prepared from a standard sample using fluorescent X-ray analysis.

  In the toner particles produced according to the present invention, it is preferable that the inorganic fine powder is a hydrophobized product because the environmental stability of the toner can be improved. Treatment agents used for hydrophobizing inorganic fine powders include silicone varnishes, various modified silicone varnishes, silicone oils, various modified silicone oils, silane compounds, silane coupling agents, other organic silicon compounds, and organic titanium compounds. May be used alone or in combination of two or more.

  Among the above-mentioned treatment agents, those treated with silicone oil are preferred, and those treated with silicone oil are more preferred at the same time as or after the hydrophobic treatment of the inorganic fine powder with the silane compound. As a method for treating such inorganic fine powder, for example, as a first-stage reaction, a silanization reaction is performed with a silane compound and silanol groups are eliminated by chemical bonds, and then a hydrophobic reaction is performed on the surface with silicone oil as a second-stage reaction. The thin film can be formed.

  In the toner particles produced according to the present invention, other additives such as a fluororesin powder, a zinc stearate powder, a polyvinylidene fluoride powder, a cerium oxide powder, Abrasives such as silicon powder and strontium titanate powder, fluidity-imparting agents such as titanium oxide powder and aluminum oxide powder, anti-caking agents, or organic fine particles and inorganic fine particles of opposite polarity may be used in small amounts as developability improvers. it can. It is also possible to use the surface of these additives after hydrophobizing them.

  Next, a method for measuring physical properties of toner particles obtained by the method for producing toner particles of the present invention will be described.

(1) Measurement of polymerization conversion rate About 500 mg of the toner suspension is precisely weighed in a sample bottle, and after adding about 15 g of acetone precisely weighed, this is mixed well, and ultrasonic waves are applied for 30 minutes with an ultrasonic cleaner. Irradiate. Thereafter, filtration is performed using a membrane filter (for example, disposable membrane filter 25JP020AN manufactured by Advantech Toyo Co., Ltd.), and 2 μL of the filtrate is analyzed by gas chromatography. Then, the polymerization conversion rate is calculated by a calibration curve prepared in advance using a monomer such as styrene.
Specifically, the analysis is performed under the following conditions.
GC: HP 6890GC
Column: HP INNOWax (200 μm × 0.40 μm × 25 m)
Carrier gas: He (constant pressure mode: 20 psi)
Oven: 50 ° C .: hold for 10 minutes, heat up to 200 ° C. at 10 ° C./minute, 200 ° C .: hold for 5 minutes.
INJ: 200 ° C., pulsed splitless mode (20 → 40 psi, until 0.5 min)
Split ratio: 5.0: 1.0
DET: 250 ° C (FID)

(2) Size exclusion chromatography online-multi-angle light scattering (SEC-MALLS)
After 0.03 g of toner particles are dispersed and dissolved in 10 ml of tetrahydrofuran, the mixture is shaken with a shaker at 25 ° C. for 24 hours, filtered with a 0.2 μm filter, and the filtrate is used as a sample.

[Analysis conditions]
Separation column: Shodex (TSK GMHHR-H HT20) × 2
Column temperature: 25 ° C
Mobile phase solvent: tetrahydrofuran Mobile phase flow rate: 1.0 ml / min.
Sample concentration: about 0.3%
Injection volume: 300 μl
Detector 1: Multi-angle light scattering detector Wyatt DAWN Ethylene oxide S
Detector 2: Differential refractive index detector Shodex RI-71

[Measurement theory]
(LS) = (dn / dc) ² × C × Mw × KLS (1)
(LS); Measurement voltage value of the detector (V)
(Dn / dc): Increment of refractive index per 1 g of sample (ml / g)
C: concentration (g / ml)
KLS: Coefficient of measurement voltage and scattering intensity (reduction Rayleigh ratio) (equipment constant)
In the present invention, (dn / dc) was set to 0.068 ml / g from the literature value of polystyrene.

In SEC-MALLS, the molecular size is separated by the molecular sieve of the SEC column, and Mw (absolute molecular weight) and C (concentration) are changed and eluted, so it is necessary to separately measure the concentration detector in combination with MALLS. The signal intensity is converted into a concentration C to determine the molecular weight Mw. In the present invention, a differential refractive index detector (RI) is used as a concentration detector, and the signal intensity (RI) of the RI detector is converted into a concentration C and used.
(RI) = (dn / dc) × C × KRI (2)
KRI: Coefficient of measurement voltage and refractive index (RI constant, calibrated with polystyrene standard)
The molecular size (radius of inertia) was calculated by Debye Plot.

(3) Average particle size distribution and particle size distribution of toner The weight average particle size (D4) of the toner particles produced by the production method of the present invention is an accurate particle size distribution measuring device using a pore electrical resistance method equipped with an aperture tube of 100 μm. “Coulter Counter Multisizer 3” (registered trademark, manufactured by Beckman Coulter) and attached dedicated software “Beckman Coulter Multisizer 3 Version 3.51” (manufactured by Beckman Coulter, Inc.) for measurement condition setting and measurement data analysis ), The number of effective measurement channels was 25,000, and the measurement data was analyzed and calculated.

  As the electrolytic aqueous solution used for the measurement, special grade sodium chloride is dissolved in ion-exchanged water so as to have a concentration of about 1% by mass, for example, “ISOTON II” (manufactured by Beckman Coulter, Inc.) can be used.

  Prior to measurement and analysis, dedicated software was set up as follows.

  In the “Standard Measurement Method (SOM) Change Screen” of the dedicated software, set the total count in the control mode to 50000 particles, set the number of measurements once, and set the Kd value to “standard particles 10.0 μm” (Beckman Coulter, Inc.) Set the value obtained using The threshold and noise level are automatically set by pressing the threshold / noise level measurement button. Also, the current is set to 1600 μA, the gain is set to 2, the electrolyte is set to ISOTON II, and the aperture tube flash after measurement is checked.

  In the “pulse to particle size conversion setting screen” of the dedicated software, the bin interval is set to logarithmic particle size, the particle size bin is set to 256 particle size bin, and the particle size range is set to 2 μm to 60 μm.

The specific measurement method is as follows.
(1) About 200 ml of the electrolytic aqueous solution is put in a glass 250 ml round bottom beaker exclusively for Multisizer 3, set on a sample stand, and the stirrer rod is stirred counterclockwise at 24 rotations / second. Then, dirt and bubbles in the aperture tube are removed by the “aperture flush” function of the analysis software.
(2) About 30 ml of the electrolytic aqueous solution is put in a glass 100 ml flat bottom beaker, and "Contaminone N" (nonionic surfactant, anionic surfactant, organic builder pH 7 precision measurement is used as a dispersant therein. About 0.3 ml of a diluted solution obtained by diluting a 10% by weight aqueous solution of a neutral detergent for washing a vessel (made by Wako Pure Chemical Industries, Ltd.) 3 times with ion exchange water is added.
(3) Two oscillators with an oscillation frequency of 50 kHz are incorporated in a state where the phase is shifted by 180 degrees, and placed in a water tank of an ultrasonic dispersion device “Ultrasonic Dissipation System Tetora 150” (manufactured by Nikki Bios Co., Ltd.) having an electrical output of 120 W. A fixed amount of ion-exchanged water is added, and about 2 ml of the above-mentioned Contaminone N is added to this water tank.
(4) The beaker of (2) is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. And the height position of a beaker is adjusted so that the resonance state of the liquid level of the electrolyte solution in a beaker may become the maximum.
(5) In a state where the electrolytic aqueous solution in the beaker of (4) is irradiated with ultrasonic waves, about 10 mg of toner is added to the electrolytic aqueous solution little by little and dispersed. Then, the ultrasonic dispersion process is continued for another 60 seconds. In the ultrasonic dispersion, the temperature of the water tank is appropriately adjusted so as to be 10 ° C. or higher and 40 ° C. or lower.
(6) To the round bottom beaker of (1) installed in the sample stand, the electrolyte solution of (5) in which the toner is dispersed is dropped using a pipette, and the measurement concentration is adjusted to about 5%. . The measurement is performed until the number of measured particles reaches 50,000.
(7) Analyze the measured data using the dedicated software attached to the device, and calculate the weight average particle size (D4. Analytical / volume statistics (arithmetic when graph / volume% is set with the dedicated software) The “average diameter” on the (average) screen is the weight average particle diameter (D4).

(4) Average Circularity of Toner Particles The measurement principle of the flow type particle image analyzer “FPIA-3000” (manufactured by Sysmex Corporation) is to capture flowing particles as a still image and perform image analysis. The sample added to the sample chamber is fed into the flat sheath flow cell by a sample suction syringe. The sample fed into the flat sheath flow is sandwiched between sheath liquids to form a flat flow. The sample passing through the flat sheath flow cell is irradiated with stroboscopic light with a nucleus for 1/60 second, and the flowing particles can be photographed as a still image. Further, since the flow is flat, the image is taken in a focused state. The particle image is captured by a CCD camera, and the captured image is subjected to image processing at an image processing resolution of 512 × 512 (0.19 μm × 0.19 μm per pixel), and the contour of each particle image is extracted, The projected area S, the peripheral length L, and the like are measured.

Next, the equivalent circle diameter and the circularity are obtained using the area S and the peripheral length L. The equivalent circle diameter is the diameter of a circle having the same area as the projected area of the particle image, and the circularity C is a value obtained by dividing the circumference of the circle obtained from the equivalent circle diameter by the circumference of the projected particle image. And is calculated by the following formula.
Circularity C = 2 × (π × S) ^1/2 / L

  When the particle image is circular, the degree of circularity is 1, and the degree of unevenness on the outer periphery of the particle image increases, and the degree of circularity decreases. After calculating the circularity of each particle, the arithmetic average value of the obtained circularity is calculated, and the value is defined as the average circularity.

(6) Peak molecular weight (Mp) of tetrahydrofuran (THF) soluble matter
The molecular weight distribution of the THF soluble part of the toner particles is measured by gel permeation chromatography (GPC) as follows.

First, toner particles are dissolved in tetrahydrofuran (THF) at room temperature over 24 hours. The obtained solution is filtered through a solvent-resistant membrane filter “Maescho Disc” (manufactured by Tosoh Corporation) having a pore diameter of 0.2 μm to obtain a sample solution. The sample solution is adjusted so that the concentration of the component soluble in THF is about 0.8% by mass. Using this sample solution, measurement is performed under the following conditions.
Apparatus: HLC8120 GPC (detector: RI) (manufactured by Tosoh Corporation)
Column: Seven series of Shodex KF-801, 802, 803, 804, 805, 806, 807 (manufactured by Showa Denko KK)
Eluent: Tetrahydrofuran (THF)
Temperature: 25 ° C
Flow rate: 1.0 ml / min
Oven temperature: 40.0 ° C
Sample injection volume: 0.10 ml

  In calculating the molecular weight of the sample, standard polystyrene resin (for example, trade name “TSK Standard Polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F— 10, F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500 ", manufactured by Tosoh Corporation) are used.

  Hereinafter, the present invention will be described more specifically with reference to production examples and examples, but these do not limit the present invention in any way. In addition, all the parts in the following mixing | blending show a mass part.

<Manufacture of magnetic substance A>
During an aqueous ferrous sulfate solution, 1.10 eq of sodium hydroxide solution from 1.00 relative to iron element, the amount of P ₂ O ₅ to an iron element to be 0.15% by mass in terms of phosphorus, the iron element On the other hand, SiO ₂ in an amount of 0.50% by mass in terms of silicon element was mixed to prepare an aqueous solution containing ferrous hydroxide. The pH of the aqueous solution was 8.0, and an oxidation reaction was performed at 85 ° C. while blowing air to prepare a slurry liquid having seed crystals.

  Subsequently, after adding ferrous sulfate aqueous solution so that it may become 0.90 to 1.20 equivalent with respect to the original alkali amount (sodium component of caustic soda) to this slurry liquid, the slurry liquid is maintained at pH 7.6, The oxidation reaction was promoted while blowing air to obtain a slurry liquid containing magnetic iron oxide. After filtration and washing, the water-containing slurry was once taken out. At this time, a small amount of water-containing sample was collected and the water content was measured. Next, this water-containing sample is put into another aqueous medium without being dried, stirred and redispersed with a pin mill while circulating the slurry, and the pH of the redispersed liquid is adjusted to about 4.8. Then, 1.6 parts of n-hexyltrimethoxysilane coupling agent was added to 100 parts of magnetic iron oxide with stirring (the amount of magnetic iron oxide was calculated as a value obtained by subtracting the water content from the water-containing sample), and water was added. Decomposition was performed. Thereafter, the mixture was sufficiently stirred, and the pH of the dispersion was adjusted to 8.6 to perform a hydrophobic treatment. The produced hydrophobic magnetic material is filtered with a filter press, washed with a large amount of water, dried at 100 ° C. for 15 minutes, and then at 90 ° C. for 30 minutes. A 0.21 μm magnetic material A was obtained.

<Manufacture of toner particles 1>
450 parts of 0.1M Na ₃ PO ₄ aqueous solution is added to 720 parts of ion-exchanged water and heated to 60 ° C., and then 67.7 parts of 1.0M CaCl ₂ aqueous solution is added to contain a dispersion stabilizer. An aqueous medium was obtained.

-Styrene 74.00 parts-n-Butyl acrylate 26.00 parts-Divinylbenzene 0.52 parts-Iron complex of monoazo dye (T-77: manufactured by Hodogaya Chemical Co., Ltd.) 1.50 parts-Magnetic substance A 90.0 parts Saturated polyester resin 5.0 parts (saturated polyester resin obtained by condensation reaction of bisphenol A ethylene oxide ethylene oxide adduct and terephthalic acid Mn = 5000, acid value = 12 mgKOH / g, Tg = 68 ° C.)
The above formulation was uniformly dispersed and mixed using an attritor (Mitsui Miike Chemical Co., Ltd.) to obtain a monomer composition. This monomer composition was heated to 60 ° C., and 15.0 parts of paraffin wax (manufactured by Toyo Petrolite; HNP-9, melting point: 75 ° C.) was added and mixed to dissolve and dissolve.

The monomer composition was charged into the aqueous medium, and granulated by stirring at 12,000 rpm for 10 minutes in a TK homomixer (Special Machine Industries Co., Ltd.) in an N ₂ atmosphere at 60 ° C. Thereafter, 4.0 parts of di-sec-butyl peroxydicarbonate was added as a polymerization initiator A, the reaction temperature T (JA) was kept at 70 ° C. while stirring with a paddle stirring blade, and the polymerization conversion rate was 80.0%. At that time, 1.0 part of potassium persulfate was added, and the mixture was further reacted for 3 hours.

  After completion of the reaction, the suspension was cooled, washed with hydrochloric acid, filtered and dried to obtain toner particles 1 having a weight average particle diameter (D4) of 7.1 μm and 100 parts of binder resin. . The physical properties of the toner particles 1 are shown in Table 2.

  100 parts of this toner particle 1 and 1.0 part of hydrophobic silica fine powder having a number average primary particle size of 12 nm were mixed with a Henschel mixer (Mitsui Miike Chemical Co., Ltd.) to obtain toner 1.

<Manufacture of toner particles 2>
450 parts of 0.1M Na ₃ PO ₄ aqueous solution is added to 720 parts of ion-exchanged water and heated to 60 ° C., and then 67.7 parts of 1.0M CaCl ₂ aqueous solution is added to contain a dispersion stabilizer. An aqueous medium was obtained.

-Styrene 74.00 parts-n-Butyl acrylate 26.00 parts-Divinylbenzene 0.52 parts-Iron complex of monoazo dye (T-77: manufactured by Hodogaya Chemical Co., Ltd.) 1.50 parts-Magnetic substance A 90.0 parts Saturated polyester resin 5.0 parts (saturated polyester resin obtained by condensation reaction of bisphenol A ethylene oxide ethylene oxide adduct and terephthalic acid Mn = 5000, acid value = 12 mgKOH / g, Tg = 68 ° C.)
The above formulation was uniformly dispersed and mixed using an attritor (Mitsui Miike Chemical Co., Ltd.) to obtain a monomer composition. This monomer composition was heated to 60 ° C., and 15.0 parts of paraffin wax (manufactured by Toyo Petrolite; HNP-9, melting point: 75 ° C.) was added and mixed to dissolve and dissolve.

The monomer composition was charged into the aqueous medium, and granulated by stirring at 12,000 rpm for 10 minutes in a TK homomixer (Special Machine Industries Co., Ltd.) in an N ₂ atmosphere at 60 ° C. Thereafter, 4.0 parts of di-isopropyl peroxydicarbonate was added as a polymerization initiator A, and the reaction temperature T (JA) was kept at 70 ° C. while stirring with a paddle stirring blade. When the polymerization conversion reached 40.0%, 1.0 part of di-isopropyl peroxydicarbonate was added. Furthermore, when the polymerization conversion rate reached 80.0%, 1.0 part of ammonium persulfate was added, and the reaction was further continued for 3 hours.

  After completion of the reaction, the suspension was cooled, washed with hydrochloric acid, filtered and dried to obtain toner particles 2 having a weight average particle diameter (D4) of 7.1 μm and 100 parts of binder resin. . Table 2 shows the physical properties of Toner Particles 2.

  100 parts of the toner particles 2 and 1.0 part of hydrophobic silica fine powder having a number average primary particle size of 12 nm were mixed with a Henschel mixer (Mitsui Miike Chemical Co., Ltd.) to obtain toner 2.

<Production of toner particles 3 to 23>
In the production of the toner particles 1, as shown in Table 1, the polymerization initiator A and the amount thereof, the polymerization initiator B and the amount thereof, the addition timing of the polymerization initiator B, and the reaction temperature T (JA) are changed. 3 to 23 were obtained. Table 2 shows the physical properties of Toner Particles 3 to 23. Further, in the same manner as in the production of the toner 1, toners 3 to 23 were obtained.

<Manufacture of toner particles 24 and 25>
In the production of the toner particles 1, as shown in Table 1, the polymerization initiator A and the amount thereof, the polymerization initiator B and the amount thereof, the addition timing of the polymerization initiator B, and the reaction temperature T (JA) are changed. 24 and 25 were obtained. Table 2 shows the physical properties of the toner particles 24 and 25. Further, in the same manner as in the production of the toner 1, toners 24 and 25 were obtained.

<Production of Toner Particles 26>
In the production of the toner particles 1, the polymerization initiator B was changed to oil-soluble di-isopropyl peroxydicarbonate to obtain toner particles 26. Table 2 shows the physical properties of the toner particles 26. Further, the toner 26 was obtained in the same manner as in the production of the toner 1.

<Manufacture of toner particles 27 to 34>
In the production of the toner particles 1, as shown in Table 1, the polymerization initiator A and the amount thereof, the polymerization initiator B and the amount thereof, the addition timing of the polymerization initiator B, and the reaction temperature T (JA) are changed. 27 to 34 were obtained. Table 2 shows the physical properties of the toner particles 27 to 34. Further, in the same manner as in the production of the toner 1, toners 27 to 34 were obtained.

<Example 1>
(Image forming device)
As an image forming apparatus, LBP-3410 (manufactured by Canon Inc.) was used for toner evaluation.

(Cleanability test)
The cleaning property test was conducted under the following conditions.

Under normal temperature and humidity (23 ° C, 60% RH), 9000 prints were tested in continuous mode with images consisting only of vertical lines with a printing rate of 4%, and cleaning was performed according to the criteria shown below. Judged the level of failure. As media, Letter 75 g / m ² paper was used. When the toner 1 was evaluated using these conditions, no defective cleaning occurred even after the endurance of 9000 sheets, and a good image was obtained. The evaluation results are shown in Table 3.

(Fixing test)
The fixing test was performed under the following conditions.

Evaluation was performed in a normal temperature and humidity environment (23 ° C., 60% RH). FRB90g paper was used as the medium, and the development bias was set so that the image density of the halftone image was 0.80 to 0.85. Next, the fixing device was cooled to room temperature, the heater temperature of the fixing device was set (hereinafter referred to as the fixing temperature), and after passing power, the image was passed through and fixed. Thereafter, the fixed image was rubbed 10 times with a Silbon paper to which a weight of 50 g / cm ² was applied, and the temperature at which the density reduction rate of the fixed image after the rub was 15% was determined as the fixing start temperature. When the toner 1 was evaluated using these conditions, the fixing temperature was as low as 185 ° C. The evaluation results are shown in Table 3.

(Transferability test)
The transferability test was performed under the following conditions.

  Evaluation was performed in a normal temperature and humidity environment (23 ° C., 60% RH). The transfer residual toner on the photosensitive electrophotographic photosensitive drum at the time of solid image formation was removed by taping with a transparent polyester adhesive tape. Each density difference was calculated by subtracting the density of the adhesive tape only on the paper from the density of the adhesive tape peeled off on the paper. When toner 1 was evaluated using these conditions, the transferability was very good at rank A. The evaluation results are shown in Table 3.

  The evaluation methods for each evaluation performed in the examples and comparative examples of the present invention and the judgment criteria thereof will be described below.

[Image density]
The image density formed a solid image portion, and the density of the solid image was measured with a Macbeth reflection densitometer (manufactured by Macbeth).

[Cleanability]
The evaluation of the cleaning performance was evaluated for the degree of dirt on the solid white image and the degree of dirt on the electrostatic latent image carrier after the solid white image was printed over the endurance of 9000 sheets in a room temperature and humidity environment. did.
A: Clean image quality with no problem on the image and no stain on the image carrier.
B: A cleaning property in which an image having no problem on the image can be obtained, but the image carrier is rarely stained.
C: Cleaning property with low occurrence frequency although stains due to poor cleaning are rarely seen on the image.
D: Although there is a stain due to poor cleaning on the image, it is an image that is difficult to recognize.
E: Contamination due to poor image cleaning is observed, which is not preferable for practical use.

[Transferability]
A: Transferability that is very good when it is less than 0.05 B: Transferability that is good when it is 0.05 or more and less than 0.10 C: Transfer that is 0.10 or more but less than 0.15 and has no practical problem Property D: 0.15 or more, practically undesirable transferability

<Examples 2 to 23>
An image output test was performed in the same manner as in Example 1 except that the toners 2 to 23 were used. As a result, an image of a level that is not problematic for any toner was obtained. The evaluation results are shown in Table 3.

<Comparative Examples 1 to 11>
An image formation test was performed in the same manner as in Example 1 except that the toners 24 to 34 were used. As a result, poor cleaning occurred, and the low-temperature fixability was partially poor. The evaluation results are shown in Table 3.

  DESCRIPTION OF SYMBOLS 100 Electrostatic latent image carrier (photoreceptor), 102 Toner carrier, 114 Transfer member (transfer roller), 116 Cleaner, 117 Contact charging member (charge roller), 121 Laser generator (latent image forming means, exposure device) , 123 laser, 124 register roller, 125 transport belt, 126 fixing device, 140 developing device, 141 stirring member

Claims (7)

The polymerizable monomer composition having containing a polymerizable monomer and a colorant is added to the aqueous medium, in aqueous medium to form particles of the polymerizable monomer composition, polymerizable monomer the polymerizable monomer contained in the particles of the body composition using a polymerization initiator is polymerized to obtain toner particles, a process for the preparation of toner particles,
The polymerization initiator, was added in several times,
Polymerization initiator A added to the first-time, those selected from the group consisting of peroxydicarbonate and diacyl peroxide,
A polymerization initiator B was added when the polymerization conversion reached below 99.5% 60.0%,
The polymerization initiator B is a water-soluble polymerization initiator,
Polymerization initiator 10-hour half-life was measured using a toluene A temperature T (A) (℃) is, and at 40 ° C. or higher 62 ° C. or less,
During the period from the addition of the polymerization initiator A to addition of polymerization initiator B, keeping the temperature T of the aqueous medium so as to satisfy the following equation 1 (JA) (℃) (Equation 1) T (A ) + 25 ≦ T (JA) ≦ T (A) +36
And a method for producing toner particles. Method for producing the polymerizable respect monomer 100 parts by weight of the polymerization initiator A toner particle according to the 請 Motomeko 1 Ru der 10.0 parts by mass or more 1.0 part by mass. Wherein the polymerizable monomer 100 parts by weight of the polymerization initiator method for producing B toner particles according to 請 Motomeko 1 or 2 Ru der least 0.2 part by weight 10.0 parts by weight. The polymerization initiator A is di-sec-butyl peroxydicarbonate, diisopropyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate, di-n-propyl peroxydicarbonate or dilauroyl peroxide. Item 4. The method for producing toner particles according to any one of Items 1 to 3. The method for producing toner particles according to claim 1, wherein the polymerization initiator B is potassium persulfate or ammonium persulfate. Tetrahydrofuran-soluble matter the size exclusion chromatography of the toner particles - Online - weight average molecular weight Mw when measured by multi-angle light scattering (SEC-MALLS) is, is 5,000 or more 25,000,
The tetrahydrofuran-soluble matter the size exclusion chromatography of the toner particles - Online - Multi-angle light scattering (SEC-MALLS) The weight average molecular weight when measured at Mw and inertial square radius Rw satisfies the following formula 2
(Formula 2) 2.0 × 10 ⁻³ ≦ Rw / Mw ≦ 1.0 × 10 ⁻²
Method for producing toner particles according to any one of claims 1-5. DOO toner produced by the production method of the toner particles according to any one of claims 1-6.

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