JP7412903B2 - Toner manufacturing method - Google Patents

Description

The present invention relates to a method for producing toner used in electrophotography and electrostatic recording.

In recent years, methods for visualizing image information through electrostatic latent images, such as electrophotography, have been used in a variety of fields, and in addition to further improving image quality and speed, they have also been used to make copiers and printers smaller and more energy efficient. Longer life is required.
Toner production methods such as suspension polymerization and dissolution/suspension methods, in which a toner particle composition is placed in an aqueous medium and granulated by mechanical shearing, are easy to control the particle size and distribution of the toner, and are highly efficient. Since it is advantageous in improving image quality, its manufacturing method has been studied. On the other hand, it is difficult to control the shape of the toner particles, and the toner particles have a shape close to a perfect sphere, so while the transferability is excellent, the cleaning performance is poor.
On the other hand, Patent Document 1 considers a method of making toner particles irregular in shape by controlling the dissolution and re-deposition of a dispersion stabilizer in a suspension polymerization method.
Although this method improves cleaning performance, it tends to disrupt the particle size distribution of the toner because it is a method of shaping the toner at the beginning of the granulation process or suspension polymerization process. It has become clear that there is still room for improvement in meeting sexual needs.

Japanese Patent Application Publication No. 2017-155154

With conventional techniques, although improvements have been recognized in cleaning properties during development, the particle size distribution tends to be disordered and problems arise in terms of toner durability. In other words, the problem to be solved by the present invention is to provide a method for manufacturing a toner that has excellent cleaning properties by making the toner surface irregularly shaped while maintaining the durability of the toner with a good particle size distribution. be.

The inventors of the present invention conducted intensive studies to solve the above problem, and as a result, they found that the problem can be solved by the following method for manufacturing toner particles.
That is, the present invention includes a step of preparing a suspension by dispersing a polymerizable monomer composition containing a polymerizable monomer and a fatty acid metal salt in an aqueous medium containing a dispersion stabilizer.
adding a water-soluble metal salt to the suspension;
Polymerizing the polymerizable monomer contained in the suspended particles in the suspension to which the water-soluble metal salt is added, producing polymer particles containing the polymer produced by the polymerization, obtaining a dispersion liquid in which particles are dispersed , and
Alkaline treatment in which the dispersion is heated to a temperature equal to or higher than the glass transition point of the polymer contained in the polymer particles, and the pH of the dispersion is maintained under conditions of 7.5 or more and 10.0 or less. process,
A method for producing a toner having the following steps:
The water-soluble metal salt is a salt of a divalent or higher valent metal,
The pH of the suspension before adding the water-soluble metal salt is 4.0 or more and less than 6.5 .
The present invention relates to a toner manufacturing method characterized by the following.
In another form, a suspension is prepared by dispersing a mixed liquid prepared by mixing a binder resin, a fatty acid metal salt , and an organic solvent in an aqueous medium containing a dispersion stabilizer. process,
adding a water-soluble metal salt to the suspension;
The organic solvent contained in the suspended particles in the suspension to which the water-soluble metal salt is added is removed to produce polymer particles containing the binder resin, and the polymer particles are dispersed. obtaining a dispersion liquid , and
an alkali treatment step of heating the dispersion to a temperature equal to or higher than the glass transition point of the binder resin and maintaining the pH of the dispersion under conditions of 7.5 or more and 10.0 or less;
A method for producing a toner having the following steps:
The water-soluble metal salt is a salt of a divalent or higher valent metal,
The pH of the suspension before adding the water-soluble metal salt is 4.0 or more and less than 6.5 .
The present invention relates to a toner manufacturing method characterized by the following.
Still another form is a step of preparing a suspension by dispersing a liquid mixture prepared by mixing a binder resin, a fatty acid metal salt , and an organic solvent in an aqueous medium containing a dispersion stabilizer. ,
adding a water-soluble metal salt to the suspension ; and
The suspension to which the water-soluble metal salt has been added is heated to a temperature equal to or higher than the glass transition point of the binder resin, and the pH of the suspension is set to 7.5 or more and 10.0 or less. The organic solvent contained in the suspended particles in the suspension is removed while carrying out an alkali treatment step in which the particles are held in a silica to form polymer particles containing the binder resin, and the polymer particles are dispersed. obtaining a dispersion liquid,
A method for producing a toner having the following steps:
The water-soluble metal salt is a salt of a divalent or higher valent metal,
The pH of the suspension before adding the water-soluble metal salt is 4.0 or more and less than 6.5 .
The present invention relates to a toner manufacturing method characterized by the following.
Still another form is a step of preparing a suspension by dispersing a liquid mixture prepared by mixing a binder resin, a fatty acid metal salt , and an organic solvent in an aqueous medium containing a dispersion stabilizer. ,
adding a water-soluble metal salt to the suspension;
The suspension to which the water-soluble metal salt has been added is heated to a temperature equal to or higher than the glass transition point of the binder resin, and the pH of the suspension is set to 7.5 or more and 10.0 or less. an alkaline treatment step , in which the
After the step of heating to a temperature equal to or higher than the glass transition point of the binder resin and maintaining the pH of the suspension under conditions of 7.5 or more and 10.0 or less, the suspension in the suspension removing the organic solvent contained in the particles to produce polymer particles containing the binder resin to obtain a dispersion in which the polymer particles are dispersed;
A method for producing a toner having the following steps:
The water-soluble metal salt is a salt of a divalent or higher valent metal,
The pH of the suspension before adding the water-soluble metal salt is 4.0 or more and less than 6.5 .
The present invention relates to a toner manufacturing method characterized by the following.

According to the present invention, it is possible to provide a method for producing a toner that has excellent cleanability by making the surface of the toner irregular while maintaining the durability of the toner while keeping the particle size distribution of the toner well-aligned.

The present invention will be explained in detail below.

In a first embodiment of the present invention, a suspension is prepared by dispersing a polymerizable monomer composition containing a polymerizable monomer and a fatty acid metal salt in an aqueous medium containing a dispersion stabilizer. process,
adding a water-soluble metal salt to the suspension;
Polymerizing the polymerizable monomer contained in the suspended particles in the suspension to which the water-soluble metal salt is added, producing polymer particles containing the polymer produced by the polymerization, and producing the polymer particles. and heating the dispersion to a temperature equal to or higher than the glass transition point of the polymer contained in the polymer particles, and adjusting the pH of the dispersion to 7.5 or more and 10. a step of holding under conditions of 0 or less;
A method for producing a toner having the following steps:
The water-soluble metal salt is a salt of a divalent or higher valent metal,
The method for producing a toner is characterized in that the pH of the suspension before adding the water-soluble metal salt is 4.0 or more and less than 6.5.

Further, as a second form, a step of preparing a suspension by dispersing a liquid mixture of a binder resin, a fatty acid metal salt, and an organic solvent in an aqueous medium containing a dispersion stabilizer;
adding a water-soluble metal salt to the suspension;
The organic solvent contained in the suspended particles in the suspension to which the water-soluble metal salt was added was removed to produce polymer particles containing the binder resin, and the polymer particles were dispersed. a step of obtaining a dispersion liquid, and a step of heating the dispersion liquid to a temperature equal to or higher than the glass transition point of the binder resin, and maintaining the pH of the dispersion liquid under conditions of 7.5 or more and 10.0 or less,
A method for producing a toner having the following steps:
The water-soluble metal salt is a salt of a divalent or higher valent metal,
The method for producing a toner is characterized in that the pH of the suspension before adding the water-soluble metal salt is 4.0 or more and less than 6.5.

Furthermore, as a third form, a step of preparing a suspension by dispersing a mixture of a binder resin, a fatty acid metal salt, and an organic solvent in an aqueous medium containing a dispersion stabilizer;
adding a water-soluble metal salt to the suspension; heating the suspension to which the water-soluble metal salt has been added to a temperature equal to or higher than the glass transition point of the binder resin; While maintaining the pH of 7.5 or more and 10.0 or less, the organic solvent contained in the suspended particles in the suspension is removed to remove the polymer particles containing the binder resin. producing a dispersion liquid in which the polymer particles are dispersed;
A method for producing a toner having the following steps:
The water-soluble metal salt is a salt of a divalent or higher valent metal,
The method for producing a toner is characterized in that the pH of the suspension before adding the water-soluble metal salt is 4.0 or more and less than 6.5.

Furthermore, as a fourth form, a step of preparing a suspension by dispersing a mixture of a binder resin, a fatty acid metal salt, and an organic solvent in an aqueous medium containing a dispersion stabilizer;
adding a water-soluble metal salt to the suspension;
Heating the suspension to which the water-soluble metal salt is added to a temperature equal to or higher than the glass transition point of the binder resin, and maintaining the pH of the suspension under conditions of 7.5 or more and 10.0 or less. After the step of heating to a temperature equal to or higher than the glass transition point of the binder resin and maintaining the pH of the suspension under conditions of 7.5 or more and 10.0 or less, removing the organic solvent contained in the suspended particles to produce polymer particles containing the binder resin to obtain a dispersion in which the polymer particles are dispersed;
A method for producing a toner having the following steps:
The water-soluble metal salt is a salt of a divalent or higher valent metal,
The method for producing a toner is characterized in that the pH of the suspension before adding the water-soluble metal salt is 4.0 or more and less than 6.5.

The toner (toner particles) obtained with these forms has a good particle size distribution and has excellent cleaning properties due to surface irregularities, so it can meet high demands for toner developability.

Although the detailed reason why the toner particles obtained according to the present invention have such effects is not clear, the inventors of the present invention think as follows.

Although the description will be made using the first form, which is a typical form, it is believed that the effects are expressed by the same mechanism in the second to fourth forms.

In general, fatty acid metal salts contained in polymerizable monomer compositions have high polarity, so when they are dispersed in an aqueous medium containing a dispersion stabilizer to form a suspension, they tend to be unevenly distributed on the surface of suspended particles. It is in. A part of the fatty acid metal salt unevenly distributed on the surface of the suspended particles is oriented toward the aqueous medium and dissociated into fatty acid ions and metal ions. The interaction between the fatty acid ions and the dispersion stabilizer causes the dispersion stabilizer to be adsorbed to the suspended particles, thereby stabilizing the suspension.

In the toner particle manufacturing method of the present invention, dissociation of the fatty acid metal salt is suppressed by adding a water-soluble metal salt to the suspension in the toner particle manufacturing process. Polymerizing the polymerizable monomer contained in the suspended particles in the suspension to which the water-soluble metal salt is added, producing polymer particles containing the polymer produced by the polymerization, and producing the polymer particles. After obtaining a dispersion in which is dispersed, the dispersion is heated to a temperature equal to or higher than the glass transition point of the polymer contained in the polymer particles, and the pH of the dispersion is changed to an alkaline side ( (hereinafter referred to as alkali treatment). This alkali treatment accelerates the dissociation of the fatty acid metal salt at once, and rapidly improves the adsorption force between the polymer particles and the dispersion stabilizer, resulting in uneven adsorption of the dispersant, which causes the surface of the toner particles to become uneven. The authors believe that it will become a variant.

In the method for producing toner particles of the present invention, a step of adding a water-soluble metal salt to the suspension is essential. When the water-soluble metal salt is ionized in the aqueous medium of the suspension, the ion concentration in the aqueous medium increases, biasing the dissociation equilibrium of the fatty acid metal salt to the non-dissociation side, and dissolving the dispersion stabilizer. can suppress the adsorption force of This increases the adsorption force change with the dispersion stabilizer when alkali treatment is performed in a subsequent step, making it possible to make the surface irregularly shaped.

The form in which the water-soluble metal salt is added is not particularly limited as long as it is sufficiently dissolved in the aqueous medium and can be ionized. It may be added to an aqueous medium after being dissolved in a solvent.

In the method for producing toner particles of the present invention, it is essential that the pH of the suspension before adding the water-soluble metal salt is 4.0 or more and less than 6.5. If the pH of the suspension is less than 4.0, the adsorption power of the dispersion stabilizer becomes too low when the water-soluble metal salt is added, so that the suspended particles tend to coalesce and the particle size distribution widens. It ends up. If the pH of the suspension is 6.5 or higher, most of the fatty acid metal salt has already been dissociated, so even if alkali treatment is performed in the subsequent step, the adsorption force with the dispersion stabilizer will change. The surface will not become irregularly shaped. There are no restrictions on the timing of adding the water-soluble metal salt other than adding it to the suspension having a pH within the above range. Good too.

The water-soluble metal salt used in the present invention is essential to be a salt of a divalent or higher-valent metal. When a monovalent metal salt is used, the dissociation equilibrium is less biased toward the non-dissociation side, and the surface irregularity effect of the present invention cannot be obtained. In addition, when a salt of a divalent or higher metal is used, the ions of the metal form a crosslinked structure with the polar material on the surface of the suspended particles, increasing the strength of the suspended particles and making the surface irregular. be able to. For the same reason, it is more preferable to use a trivalent metal salt.

The amount of the water-soluble metal salt added in the present invention is preferably from 150 to 850 parts by mole per 100 parts by mole of the fatty acid metal salt. By setting the amount of the water-soluble metal salt added to 150 parts by mole or more per 100 parts by mole of the fatty acid metal salt, the dissociation equilibrium is sufficiently biased toward the non-dissociation side, and efficient surface modification can be carried out. can. Furthermore, by setting the amount of the water-soluble metal salt added to 850 parts by mole or less per 100 parts by mole of the fatty acid metal salt, the effect of the addition of the water-soluble metal salt as a flocculant can be suppressed, thereby reducing concerns in the manufacturing process. Coalescence of cloudy liquid can be suppressed.

In the method for producing toner particles of the present invention, the surface irregular shape of the toner particles is realized by controlling the dissociation state of the fatty acid metal salt as described above. As the fatty acid metal salt, any conventionally known fatty acid metal salt can be used without particular limitation as long as it is a poorly water-soluble fatty acid metal salt consisting of a fatty acid and a metal. Specifically, fatty acids include linear saturated fatty acids such as nonanoic acid, lauric acid, stearic acid, and cerotic acid, linear unsaturated fatty acids such as oleic acid and linoleic acid, and branched fatty acids such as 15-methylhexadecanoic acid. Known fatty acids can be used, such as fatty acids with other functional groups, such as fatty acids with 2-hydroxydodecanoic acid and 12-hydroxystearic acid.

As the metal constituting the fatty acid metal salt, known metals can be used. Specific examples include Na, Al, Ba, Ca, Mg, Zn, Fe, In, Cu, Ti, Co, and Zr. Among these, polyvalent metals having a valence of two or more are preferred from the viewpoint of crosslinking the surface of suspended particles. More preferably, it is a polyvalent metal of trivalent or higher valence.

Moreover, from the viewpoint of complex stability with fatty acids, Al, Fe, and Cu are preferable.

The amount of the fatty acid metal salt added is 0.05 parts by mass or more and 1.5 parts by mass based on 100 parts by mass of the polymerizable monomer in the first form or the binder resin in the second to fourth forms. It is preferable that it is less than When the amount of fatty acid metal salt added is 0.05 parts by mass or more, surface irregularization is promoted, and when it is less than 1.5 parts by mass, plasticization of toner particles due to excess fatty acid is suppressed, and durability is improved. improves.

In the method for producing toner particles of the present invention, as described above, as a trigger for surface irregularization, heating is performed to a temperature equal to or higher than the glass transition point of the polymer contained in the polymer particles, and the pH of the dispersion is adjusted to 7. A step (alkali treatment) of maintaining the temperature under conditions of .5 or more and 10.0 or less is essential.

When the alkali treatment is carried out at a temperature below the glass transition point of the polymer, the polymer exists in a glass state, and therefore surface deformation due to the weak adsorption force with the dispersant does not occur.

Furthermore, if the pH of the dispersion during alkali treatment is less than 7.5, the change in adsorption power with the dispersant is small and surface irregularities are less likely to occur. On the other hand, if the pH of the dispersion during alkali treatment is more than 10.0, there is a concern that various polymers in the toner particles will be hydrolyzed and the resulting toner particles will become brittle.

In the method for producing toner particles of the present invention, it is preferable to perform a step of adding resin particles and fixing the resin particles to the surface of the toner base particles (polymer particles) in the alkali treatment step. By fixing the resin particles to the surface of the polymer particles, the development durability of the toner can be improved.

Further, it is more preferable that the resin particles to be fixed contain a polymer A having a monovalent group a represented by the following formula (1).

（式（１）中、Ｒ¹は、ヒドロキシ基、カルボキシ基、炭素数１以上１８以下のアルキル基、または、炭素数１以上１８以下のアルコキシ基を表し、Ｒ²は、水素原子、ヒドロキシ基、炭素数１以上１８以下のアルキル基、または、炭素数１以上１８以下のアルコキシ基を表し、ｇは１以上３以下の整数を表し、ｈは０以上３以下の整数を表す。ｈが２または３である場合、ｈ個のＲ¹は、同一であっても異なっていてもよい。）

(In formula (1), R ¹ represents a hydroxy group, a carboxy group, an alkyl group having 1 to 18 carbon atoms, or an alkoxy group having 1 to 18 carbon atoms, and R ² represents a hydrogen atom, a hydroxy group , represents an alkyl group having 1 to 18 carbon atoms, or an alkoxy group having 1 to 18 carbon atoms, g represents an integer of 1 to 3, and h represents an integer of 0 to 3. h is 2 or 3, h R ¹ 's may be the same or different.)

When the resin particles contain the polymer A having the monovalent group a represented by the above formula (1), the charging uniformity of the toner particles is improved and transferability is improved.

<Detailed explanation of the first form>
The first embodiment of the manufacturing method of the present invention has the following manufacturing steps.
- An aqueous medium preparation step for preparing an aqueous medium containing a dispersion stabilizer.
- Adding a polymerizable monomer composition containing a polymerizable monomer and a fatty acid metal salt to the aqueous medium to form suspended particles of the polymerizable monomer composition in the aqueous medium. Granulation process to obtain a suspension.
・Suspension polymerization in which the polymerizable monomer contained in the suspended particles is polymerized to produce polymer particles containing the polymer produced by the polymerization, and a dispersion liquid in which the polymer particles are dispersed is obtained. Process.
- Adding a water-soluble metal salt to the suspension or dispersion.
- An alkali treatment step in which the temperature of the dispersion is set to be higher than or equal to the Tg of the polymer contained in the polymer particles, and the pH is adjusted to be 7.5 or more and 10.0 or less.

Furthermore, the manufacturing method of the present invention can include, for example, the following composition preparation step before the granulation step.
- A composition preparation step of preparing a polymerizable monomer composition by mixing a polymerizable monomer and a fatty acid metal salt.

However, in the present invention, this composition preparation step does not need to be provided separately. During the granulation process, components constituting the polymerizable monomer composition (polymerizable monomer, fatty acid metal salt, etc.) may be added at once to the aqueous medium (in that case, some of the components may be added at once). (The ingredients may be mixed separately in advance). Furthermore, for example, one or more of these components (in that case, some of the components may be mixed separately in advance) may be suspended in stages by appropriately changing temperature conditions, stirring conditions, etc. It may be added to the suspension. Note that a part of the polymerizable monomer composition (for example, a polymerization initiator described below) may be dissolved in the aqueous medium without being contained in the polymerizable monomer composition particles. For this reason, components of the polymerizable monomer composition that can be dissolved in an aqueous medium, such as a polymerization initiator, should be removed after the granulation process (after particles of the polymerizable monomer composition are formed) and during polymerization. It may be added to the suspension (or reaction system) before the end of the process (before the polymerization reaction is completed and toner particles are formed).

That is, in the present invention, each component of the polymerizable monomer composition is not added (contained) to the suspension (or reaction system) as a result (before toner particles are formed). Good.

If a composition preparation step is provided separately, the granulation step involves dispersing the prepared polymerizable monomer composition in the aqueous medium to form suspended particles of the polymerizable monomer composition. It can be a step of granulating.

Furthermore, in the production method of the present invention, the following distillation step, washing, filtration, and drying steps can be performed on the dispersion containing polymer particles obtained from the suspension polymerization step. Furthermore, the following external addition step can also be performed on the toner particles obtained through these steps. That is, the method for producing toner particles of the present invention includes an aqueous medium preparation step, a composition preparation step, a granulation step, a suspension polymerization step, a distillation step, a washing, filtration and drying step, and an external addition step. and can include.
- A distillation step in which the obtained dispersion containing polymer particles is subjected to a distillation operation to obtain a dispersion containing polymer particles such as toner particles.
- A washing, filtration and drying step in which the resulting dispersion containing polymer particles such as toner particles is washed, filtered and dried to obtain toner particles.
- An external addition step of adding an external additive (for example, inorganic fine powder) to the obtained toner particles.

Next, each step will be explained in detail.

[Aqueous medium preparation process]
First, an aqueous medium containing a dispersion stabilizer is prepared.

(aqueous medium)
The aqueous medium in the present invention is an aqueous medium containing a dispersion stabilizer and water. In addition, this aqueous medium also contains counterions generated when producing a dispersion stabilizer, acids (e.g., hydrochloric acid and sulfuric acid) and alkalis (e.g., sodium hydroxide and sodium carbonate) added for pH adjustment. ) etc. Note that the dispersion liquid can also consist of a dispersion stabilizer and water.

-Water As the water (dispersion medium) used for preparing the aqueous medium, for example, ion-exchanged water can be used. The aqueous medium is preferably prepared using 100 parts by mass or more of water per 100 parts by mass of the polymerizable monomer. When the amount of water used is 100 parts by mass or more, oil droplets (polymerizable monomer composition particles) can be easily formed without causing oil-water inversion.

- Dispersion stabilizer The dispersion stabilizer plays a role as a dispersion stabilizer for the polymerizable monomer composition present in the suspension during the granulation process. Types of inorganic compounds used as dispersion stabilizers include hydroxyapatite, tribasic calcium phosphate, dibasic calcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, calcium carbonate, magnesium carbonate, calcium hydroxide, magnesium hydroxide, Examples include aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate, bentonite, silica, and alumina. Examples of the organic compound used as a dispersion stabilizer include polyvinyl alcohol, gelatin, methylcellulose, methylhydroxypropylcellulose, ethylcellulose, sodium salt of carboxymethylcellulose, polyacrylic acid and its salt, starch, and the like. Further, a surfactant may be used for fine dispersion of these dispersion stabilizers. This is to promote the initial action of the dispersion stabilizer. Examples of the surfactant include sodium dodecylbenzene sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, potassium stearate, and calcium oleate. When using an inorganic compound as a dispersion stabilizer, a commercially available one may be used as is, but in order to obtain finer particles, the above-mentioned inorganic compound may be produced in an aqueous medium and used. For example, in the case of calcium phosphates such as hydroxyapatite and tricalcium phosphate, it is preferable to mix the phosphate aqueous solution and the calcium salt aqueous solution under high stirring.

[Pelletization process]
A dispersion stabilizer and a polymerizable monomer composition are dispersed in the aqueous medium to prepare a suspension, that is, a granulation step. A suspension containing the polymer composition particles can be obtained. As mentioned above, all of the polymerizable monomer composition added to the suspension does not have to constitute suspended particles, and some of the added polymerizable monomer composition ( For example, a polymerization initiator) may be included in the aqueous medium.

Therefore, the relative usage amount of each component of the dispersion stabilizer and polymerizable monomer composition based on the polymerizable monomer and polymerizable monomer composition is determined by the amount of polymerizable monomer charged and It is based on the amount of polymerizable monomer composition.

Furthermore, as mentioned above, a polymerizable monomer composition is prepared by mixing a polymerizable monomer, a fatty acid metal salt, etc. in advance (composition preparation step), and the prepared polymerizable monomer The composition may be dispersed in an aqueous medium to produce suspended particles.

When granulating the suspended particles, a stirring device such as a TK homomixer (trade name, manufactured by Tokushu Kika Kogyo Co., Ltd.) can be used.

(Polymerizable monomer composition)
The polymerizable monomer composition contains a polymerizable monomer and a fatty acid metal salt, and, if necessary, a colorant, a polar resin, a polymerization initiator, a crosslinking agent, a mold release agent, and a charge control agent. , a chain transfer agent, and a polymerization inhibitor. A polymerizable monomer composition can be obtained by mixing a polymerizable monomer, a fatty acid metal salt, and these additives.

-Polymerizable monomer The polymerizable monomer can be appropriately set depending on the toner particles to be produced, and for example, a vinyl-based polymerizable monomer capable of radical polymerization can be used.

As the vinyl polymerizable monomer, a monofunctional polymerizable monomer or a polyfunctional polymerizable monomer can be used.

Examples of monofunctional polymerizable monomers include the following.

Styrene; α-methylstyrene, β-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, p-n-butylstyrene, p-tert-butylstyrene, p- Styrene derivatives such as n-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn-decylstyrene, p-n-dodecylstyrene, p-methoxystyrene, p-phenylstyrene; methyl acrylate, Ethyl acrylate, n-propyl acrylate, iso-propyl acrylate, n-butyl acrylate, iso-butyl acrylate, tert-butyl acrylate, n-amyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, n- Acrylic polymerizable monomers such as nonyl acrylate, cyclohexyl acrylate, benzyl acrylate, dimethyl phosphate ethyl acrylate, diethyl phosphate ethyl acrylate, dibutyl phosphate ethyl acrylate, 2-benzoyloxyethyl acrylate; methyl methacrylate, ethyl methacrylate, n -Propyl methacrylate, iso-propyl methacrylate, n-butyl methacrylate, iso-butyl methacrylate, tert-butyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, n-nonyl methacrylate, diethyl Methacrylic polymerizable monomers such as ethyl phosphate methacrylate and dibutyl phosphate ethyl methacrylate; methylene aliphatic monocarboxylic acid esters; vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl benzoate, and vinyl formate; vinyl Vinyl ethers such as methyl ether, vinyl ethyl ether and vinyl isobutyl ether; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone and vinyl isopropyl ketone.

Examples of the polyfunctional polymerizable monomer include the following.

Diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, tripropylene glycol diacrylate, polypropylene glycol diacrylate, 2,2 '-Bis(4-(acryloxydiethoxy)phenyl)propane, trimethylolpropane triacrylate, tetramethylolmethanetetraacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, polyethylene glycol Dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, polypropylene glycol dimethacrylate, 2,2'-bis(4-(methacryloxydiethoxy)phenyl)propane, 2,2'-bis(4-(methacryloxy polyethoxy)phenyl)propane, trimethylolpropane trimethacrylate, tetramethylolmethanetetramethacrylate, divinylbenzene, divinylnaphthalene, divinyl ether, etc.

In addition, one type of polymerizable monomer may be used alone, or a plurality of types may be used in combination.

From the viewpoint of fixing, the amount of the polymerizable monomer used is preferably 50% by mass or more of the total polymerizable monomer composition.

・Colorant The colorant should be appropriately selected and used from colorants known in the toner field, taking into consideration hue angle, saturation, brightness, weather resistance, OHT transparency, dispersibility in toner, etc. I can do it. Specifically, for example, black, yellow, magenta, and cyan pigments, which will be described later, and colorants such as dyes can be used as necessary.

Moreover, one type of coloring agent may be used alone, or a plurality of types may be used in combination. Furthermore, the colorant can also be used in the form of a solid solution.

The amount of the colorant added is preferably 1 part by mass or more and 20 parts by mass or less based on 100 parts by mass of the polymerizable monomer. By adding 1 part by mass or more of the colorant, coloring power can be easily imparted, and by adding 20 parts by mass or less, the particle size distribution can be made sharper. Note that in order to disperse a colorant such as a pigment in toner particles, the colorant can be used in a state in which it is dispersed in a solvent, and a polymerizable monomer (for example, styrene) can also be used as this solvent.

i) Black colorant As the black colorant, any known black colorant in the toner field can be used. Specific examples of the black colorant include carbon black, and further includes those prepared by mixing yellow/magenta/cyan colorants shown below to obtain black.

The carbon black is not particularly limited, but carbon black obtained by a manufacturing method such as a thermal method, an acetylene method, a channel method, a furnace method, or a lamp black method can be used. One type of carbon black may be used alone, or two or more types may be used in combination. The carbon black may be a crude pigment or may be a prepared pigment composition as long as it does not significantly inhibit the effect of the pigment dispersant.

The average particle size of the primary particles of carbon black is not particularly limited, but is preferably 14 nm or more and 80 nm or less, more preferably 25 nm or more and 50 nm or less. When the average particle size is 14 nm or more, the toner does not exhibit a reddish tinge and is preferable as a black for full-color image formation. When the average particle size of carbon black is 80 nm or less, it is preferable because it is easy to disperse well and the coloring power is not too low and it is easy to impart an appropriate coloring power.

Note that an enlarged photograph taken using a scanning electron microscope is used to measure the average particle size of carbon black. Measure the longest axis (long axis) and the shortest axis (short axis) of carbon black particles observed as primary particles on the enlarged photograph, calculate the average value of the long axis and short axis, and calculate this. This is the particle size of the measured particle. The particle size is measured for 100 carbon black particles, and the average particle size is defined as the average particle size. Note that the magnification of the scanning electron microscope may be set to such a degree that primary particles of carbon black can be confirmed.

ii) Yellow colorant As the yellow colorant, any known yellow colorant in the field of toners can be used.

As the pigment-based yellow coloring agent, for example, compounds typified by condensed polycyclic pigments, isoindolinone compounds, anthraquinone compounds, azo metal complex methine compounds, and allylamide compounds can be used. Specifically, C. I. Pigment Yellow3, 7, 10, 12, 13, 14, 15, 17, 23, 24, 60, 62, 74, 75, 83, 93, 94, 95, 99, 100, 101, 104, 108, 109, 110 , 111, 117, 123, 128, 129, 138, 139, 147, 148, 150, 155, 166, 168, 169, 177, 179, 180, 181, 183, 185, 191:1, 191, 192, 193 , 199.

Examples of dye-based yellow colorants include C.I. I. Solvent Yellow33, 56, 79, 82, 93, 112, 162, 163, C. I. Examples include disperse Yellow 42, 64, 201, and 211.

iii) Magenta Colorant As the magenta colorant, any magenta colorant known in the field of toners can be used.

As the magenta colorant, for example, fused polycyclic pigments, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds can be used. Specifically, C. I. Pigment Red 2, 3, 5, 6, 7, 23, 48:2, 48:3, 48:4, 57:1, 81:1, 122, 146, 150, 166, 169, 177, 184, 185, 202, 206, 220, 221, 238, 254, 269, C. I. Pigment Violet 19 is mentioned.

iv) Cyan Colorant As the cyan colorant, any known cyan colorant in the toner field can be used. As the cyan colorant, for example, phthalocyanine compounds and their derivatives, anthraquinone compounds, and basic dye lake compounds can be used. Specifically, C. I. Pigment Blue 1, 7, 15, 15:1, 15:2, 15:3, 15:4, 60, 62, and 66.

- Polar resin As the polar resin, for example, polyester resin, polycarbonate resin, phenol resin, epoxy resin, polyamide resin, cellulose resin, styrene acrylic resin, etc. can be used. One type of polar resin may be used alone, or a plurality of types may be used in combination.

Moreover, it is preferable that the polyester resin used as the polar resin is amorphous. If it is amorphous, heat-resistant storage stability can be imparted. In addition, whether or not it is amorphous can be specified by whether or not it has a melting point using a DSC measuring device.

The polyester resin is not particularly limited as long as it is a polyester resin obtained by polycondensing a polyhydric alcohol and a polycarboxylic acid.

Examples of polyhydric alcohol components include ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1 , 6-hexanediol, neopentyl glycol, 2-ethyl-1,3-hexanediol, cyclohexanedimethanol, butenediol, octenediol, cyclohexanedimethanol, hydrogenated bisphenol A, ethylene oxide adduct of bisphenol A, bisphenol A Examples include propylene oxide adducts.

Examples of polyhydric carboxylic acids include benzene dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, and phthalic anhydride, and their anhydrides; and alkyl dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, and azelaic acid; Examples include anhydrides.

-Polymerization initiator When polymerizing the polymerizable monomer, one or both of an oil-soluble initiator and a water-soluble initiator can be used.

Examples of oil-soluble initiators include the following. 2,2'-azobisisobutyronitrile, 2,2'-azobis-2,4-dimethylvaleronitrile, 1,1'-azobis(cyclohexane-1-carbonitrile), 2,2'-azobis-4 - Nitrile initiators such as methoxy-2,4-dimethylvaleronitrile; acetylcyclohexylsulfonyl peroxide, diisopropyl peroxycarbonate, decanonyl peroxide, lauroyl peroxide, stearoyl peroxide, propionyl peroxide, acetyl peroxide, t -Butyl peroxy-2-ethylhexanoate, benzoyl peroxide, t-butyl peroxyisobutyrate, cyclohexanone peroxide, methyl ethyl ketone peroxide, dicumyl peroxide, t-butyl hydroperoxide, di-t-butyl Peroxide-based initiators such as peroxide and cumene hydroperoxide.

Examples of water-soluble initiators include the following. Ammonium persulfate, potassium persulfate, 2,2'-azobis(N,N'-dimethyleneisobutyramidine) hydrochloride, 2,2'-azobis(2-aminodinopropane) hydrochloride, azobis(isobutyramidine) hydrochloride, sodium 2,2'-azobisisobutyronitrile sulfonate, ferrous sulfate or hydrogen peroxide.

From the viewpoint of polymerization efficiency and safety, the amount (concentration) of the polymerization initiator used is preferably 0.1 parts by mass or more and 20 parts by mass or less, and more preferably Preferably it is 0.1 parts by mass or more and 15 parts by mass or less. The above polymerization initiators can be used alone or in combination of two or more, with reference to the 10-hour half-life temperature.

-Crosslinking agent Furthermore, in the present invention, a crosslinking agent can be used during polymerization of the polymerizable monomer in order to increase the stress resistance of the toner particles and to control the molecular weight of the constituent molecules of the toner particles.

As the crosslinking agent, a compound having two or more polymerizable double bonds can be used. Specifically, aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene; carboxylic acid esters having two double bonds such as ethylene glycol diacrylate, ethylene glycol dimethacrylate, and 1,3-butanediol dimethacrylate; Examples include divinyl compounds such as divinylaniline, divinyl ether, divinyl sulfide, and divinyl sulfone; and compounds having three or more vinyl groups. These crosslinking agents may be used alone or as a mixture of two or more.

From the viewpoint of fixing properties and anti-offset properties of the toner, these crosslinking agents are preferably in the range of 0.05 parts by mass or more and 10 parts by mass or less, more preferably 0.05 parts by mass or less, based on 100 parts by mass of the polymerizable monomer. It is preferable to use it in a range of .10 parts by mass or more and 5 parts by mass or less.

- Mold release agent Furthermore, in the present invention, wax may be contained as a mold release agent. Types of wax include petroleum waxes and their derivatives such as paraffin wax, microcrystalline wax, and petrolatum; Montan wax and its derivatives; Fischer-Tropsch hydrocarbon waxes and their derivatives; polyolefin waxes such as polyethylene wax and polypropylene wax; Natural waxes and their derivatives such as their derivatives, carnauba wax and candelilla wax; Higher aliphatic alcohols; Fatty acids such as stearic acid and palmitic acid; Acid amide waxes; Ester waxes; Hardened castor oil and its derivatives; Vegetable waxes; Animals Examples include sex wax and the like. Among these, paraffin wax, ester wax, and hydrocarbon wax are particularly preferred from the viewpoint of excellent mold release properties.

From the viewpoint of mold release performance and granulation stability, the total amount of the mold release agent is preferably 2.5 parts by mass or more and 25.0 parts by mass or less based on 100 parts by mass of the polymerizable monomer. When the amount of the mold release agent is 2.5 parts by mass or more, it becomes easy to release the mold during fixing, and when it is 25.0 parts by mass or less, it is easy to form a uniform surface layer without disturbing the particle size distribution.

- Charge control agent In order to maintain the chargeability of toner particles stably regardless of the environment, the polymerizable monomer composition may contain a charge control agent in the present invention.

As the charge control agent, any known charge control agent can be used, and a charge control agent that has a fast charging speed and can stably maintain a constant charge amount is particularly preferable. Furthermore, when toner particles are produced by a direct polymerization method, a charge control agent that has low polymerization inhibiting properties and is substantially free of solubilized substances in an aqueous dispersion medium is particularly preferred. Specific examples of the negative charge control agent include metal compounds of aromatic carboxylic acids such as salicylic acid, alkylsalicylic acid, dialkylsalicylic acid, naphthoic acid, dicarboxylic acid, metal salts of azo dyes or azo pigments, and metals. Examples include complexes, boron compounds, silicon compounds, and calixarene. Examples of the positive charge control agent include quaternary ammonium salts, polymeric compounds having the quaternary ammonium salt in their side chains, guanidine compounds, nigrosine compounds, and imidazole compounds.

One type of charge control agent may be used alone, or two or more types may be used in combination.

As charge control agents other than resin-based charge control agents, metal-containing salicylic acid compounds are preferred, particularly those whose metal is aluminum or zirconium. A particularly preferred control agent is an aluminum salicylate compound.

As the resin charge control agent, it is preferable to use a polymer or copolymer having a sulfonic acid group, a sulfonic acid group, a sulfonic acid ester group, a salicylic acid moiety, or a benzoic acid moiety.

The charge control agent is preferably blended in an amount of 0.01 parts by mass or more and 20.00 parts by mass or less, more preferably 0.05 parts by mass or more and 10.00 parts by mass or less, based on 100.00 parts by mass of the polymerizable monomer. It is.

- Chain transfer agent, polymerization inhibitor In order to control the degree of polymerization of the polymerizable monomer, it is also possible to further add and use a chain transfer agent, a polymerization inhibitor, etc.

As the chain transfer agent, for example, α-methylstyrene dimer, t-dodecylmercaptan, n-dodecylmercaptan, n-octylmercaptan, carbon tetrachloride, carbon tetrabromide, etc. can be used.

Examples of polymerization inhibitors include quinone compounds such as p-penzoquinone, chloranilyl, anthraquinone, phenanesquinone, and dichlorobenzoquinone; hydroxy organic compounds such as phenol, tertiary butylcatechol, hydroquinone, catechol, and hydroxymonomethyl ether; , nitro compounds such as dinitrobenzene, dinitrotoluene, dinitrophenol, nitroso compounds such as nitrosobenzene, nitrosonaphthol, amino compounds such as methylaniline, p-phenylenediamine, N,N'-tetraethyl-p-phenylenediamine, diphenylamine, Organic sulfur compounds such as tetraalkyl uram disulfide and dithiobenzoyl disulfide can be used.

The water-soluble metal salt of the present invention may be added during this granulation step.

[Suspension polymerization process]
In a suspension containing a dispersion stabilizer and polymerizable monomer composition particles, the polymerizable monomers in the polymerizable monomer composition particles are polymerized (suspension polymerization) to form a polymer. A dispersion liquid in which particles are dispersed is obtained.

A dispersion stabilizer may be added during the polymerization process to improve the stability of the polymer particles. Additionally, water-soluble metal salts may be added during this polymerization step.

[Distillation process]
In order to remove volatile impurities such as unreacted polymerizable monomers and by-products, after the completion of polymerization, a distillation operation is performed on the dispersion containing polymer particles obtained from the polymerization process to partially disperse them. The liquid may be distilled off. The distillation step can be performed under normal pressure or reduced pressure.

The water-soluble metal salt of the invention may be added during this distillation step.

[Alkali treatment process]
After the addition of the water-soluble metal salt, the temperature of the dispersion liquid is adjusted to be higher than the Tg of the polymer contained in the polymer particles, and the pH is adjusted to 7.5 to 10.0, for the purpose of modifying the surface shape of the polymer particles. Perform an alkali treatment step. This alkali treatment step may be performed in the latter half of the polymerization, during distillation, or after completion of distillation.

Further, in the alkali treatment step, it is desirable from the viewpoint of improving durability to add resin particles to fix the resin particles to the surface of the toner base particles. From the viewpoint of transferability, it is more preferable that the resin particles to be fixed contain a polymer A having a monovalent group a represented by the following formula (1).

（式（１）中、Ｒ¹は、ヒドロキシ基、カルボキシ基、炭素数１以上１８以下のアルキル基、または、炭素数１以上１８以下のアルコキシ基を表し、Ｒ²は、水素原子、ヒドロキシ基、炭素数１以上１８以下のアルキル基、または、炭素数１以上１８以下のアルコキシ基を表し、ｇは１以上３以下の整数を表し、ｈは０以上３以下の整数を表す。ｈが２または３である場合、ｈ個のＲ¹は、同一であっても異なっていてもよい。）

(In formula (1), R ¹ represents a hydroxy group, a carboxy group, an alkyl group having 1 to 18 carbon atoms, or an alkoxy group having 1 to 18 carbon atoms, and R ² represents a hydrogen atom, a hydroxy group , represents an alkyl group having 1 to 18 carbon atoms, or an alkoxy group having 1 to 18 carbon atoms, g represents an integer of 1 to 3, and h represents an integer of 0 to 3. h is 2 or 3, h R ¹ 's may be the same or different.)

[Washing, filtration and drying process]
For the purpose of removing the dispersion stabilizer adhering to the surface of the polymer particles, a dispersion containing polymer particles such as toner particles obtained from a distillation process or the like may be treated with acid or alkali. At this time, polymer particles such as toner particles are separated into a liquid phase using a general solid-liquid separation method, but water is added again to completely remove the acid or alkali and the dispersion stabilizer component dissolved therein. to wash polymer particles such as toner particles. This washing process is repeated several times, and after sufficient washing has been performed, solid-liquid separation is performed again to obtain toner particles. The obtained toner particles can be dried by known drying means, if necessary.

[External addition process]
In the manufacturing method of the present invention, external additives can be attached to the surface of the toner particles obtained from the above-described steps for the purpose of imparting various characteristics to the toner.

From the viewpoint of durability when added to the toner particles, the external additive preferably has a particle size of 1/10 or less of the average particle size of the toner particles before the external additive is added. Examples of external additives include the following. Metal oxides such as aluminum oxide, titanium oxide, strontium titanate, cerium oxide, magnesium oxide, chromium oxide, tin oxide, zinc oxide; nitrides such as silicon nitride; carbides such as silicon carbide; calcium sulfate, barium sulfate, Inorganic metal salts such as calcium carbonate; fatty acid metal salts such as zinc stearate and calcium stearate; carbon black, silica.

These external additives are preferably used in an amount of 0.01 parts by mass or more and 10 parts by mass or less, more preferably 0.05 parts by mass or more and 5 parts by mass or less, based on 100 parts by mass of toner particles to be adhered. One type of external additive may be used alone, or a plurality of types may be used in combination. Note that, from the viewpoint of charging stability, it is preferable to use these external additives whose surfaces have been subjected to hydrophobization treatment. Examples of the hydrophobic treatment method include silane coupling agents such as methyltrimethoxysilane, methyltriethoxysilane, isobutyltrimethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, trimethylmethoxysilane, and hexamethylenedisilazane. I can do it.

- Toner particles The toner particles (toner) obtained from the present invention can be applied to image forming methods using known one-component development systems and two-component development systems.

The toner particles (toner) obtained according to the present invention can be used in any system. For example, there are toners for high-speed systems, toners for oil-less fixing, toners for cleaner-less systems, and toners for development methods that sequentially collect carriers that have deteriorated from long-term use and replenish fresh carriers. It is applicable to image forming methods using a one-component development method or a two-component development method.

<Detailed explanation of second to fourth forms>
The second to fourth embodiments of the manufacturing method of the present invention have the following manufacturing steps.
・A mixed liquid preparation process in which a mixed liquid is prepared by mixing a binder resin, a fatty acid metal salt, and an organic solvent.
- An aqueous medium preparation step for preparing an aqueous medium containing a dispersion stabilizer.
- A granulation step in which the mixed liquid is added to the aqueous medium to form suspended particles in the aqueous medium to obtain a suspension.
- Adding a water-soluble metal salt to the suspension.
・A step of removing the organic solvent contained in the suspended particles in the suspension to produce polymer particles containing the binder resin and obtaining a dispersion in which the polymer particles are dispersed (desorption). solvent process).
- An alkali treatment step in which the temperature of the dispersion is set to be equal to or higher than the Tg of the binder resin, and the pH is set to be 7.5 or more and 10.0 or less.

Furthermore, in the manufacturing method of this embodiment, the following washing, filtration, and drying steps can be performed on the dispersion containing polymer particles obtained from the above-described solvent removal step. Furthermore, the following external addition step can also be performed on the toner particles obtained through these steps. That is, the method for producing toner particles of the present embodiment may include an aqueous medium preparation step, a composition preparation step, a granulation step, a solvent removal step, a washing, filtration and drying step, and an external addition step. can.
- A washing, filtration and drying step in which the obtained dispersion containing polymer particles is washed, filtered and dried.
- An external addition step of adding an external additive (for example, inorganic fine powder) to the obtained toner particles.

Note that there is no particular restriction on the order in which the desolvation step and the alkali treatment step are performed.

As in the second embodiment of the present invention, the alkali treatment step may be performed after the solvent removal step.

As in the third embodiment of the present invention, the alkali treatment step may be performed and the solvent removal step may be performed at the same time.

After performing the alkali treatment step as in the fourth embodiment of the present invention, a solvent removal step may be performed.

Next, each step will be explained in detail.

[Mixed liquid preparation process]
First, a liquid mixture containing a binder resin, a fatty acid metal salt, and an organic solvent is prepared.

(Mixture)
The liquid mixture in this embodiment can be a liquid mixture containing a binder resin, a fatty acid metal salt, and an organic solvent. Further, if necessary, other additives such as a coloring agent, a polar resin, a mold release agent, and a charge control agent can be included.

- Binder Resin As the binder resin in this embodiment, any known resin can be used without any particular restriction as long as it is a resin that dissolves in an organic solvent. Specifically, vinyl resins, polyurethane resins, epoxy resins, polyester resins, etc. are preferred.

- Organic Solvent The organic solvent in this embodiment can be used without any particular restriction as long as it is not easily miscible with water and can dissolve the binder resin and fatty acid metal salt.

Specifically, hydrocarbon solvents such as xylene, hexane, cyclohexane, and methylcyclohexane, halogenated hydrocarbon solvents such as methylene chloride, chloroform, and dichloroethane, and ester solvents such as methyl acetate, ethyl acetate, butyl acetate, and isopropyl acetate. , ether solvents such as diethyl ether, and ketone solvents such as acetone, methyl ethyl ketone, diisobutyl ketone, and cyclohexanone.

- Coloring agent As the coloring agent, the coloring agent exemplified in the first embodiment can be used in the same manner.

- Polar resin As the polar resin, the polar resin exemplified in the first embodiment can be used in the same manner.

- Mold release agent As the mold release agent, the mold release agents exemplified in the first embodiment can be used in the same manner.

- Charge control agent As the charge control agent, the charge control agent exemplified in the first embodiment can be used in the same manner.

In this embodiment, for example, one or more of these components (in that case, some of the components may be mixed separately in advance) are mixed in stages by appropriately changing temperature conditions, stirring conditions, etc. It may also be added to the suspension. That is, in the present invention, each component of the toner particle composition may be added (contained) to the suspension (or reaction system) as a result (before toner particles are formed).

[Aqueous medium preparation process]
First, an aqueous medium containing a dispersion stabilizer is prepared.

(aqueous medium)
The aqueous medium in the present invention is an aqueous medium containing a dispersion stabilizer and water. In addition, this aqueous medium also contains counterions generated when producing a dispersion stabilizer, acids (e.g., hydrochloric acid and sulfuric acid) and alkalis (e.g., sodium hydroxide and sodium carbonate) added for pH adjustment. ) etc. Note that the dispersion liquid can also consist of a dispersion stabilizer and water.

-Water As the water (dispersion medium) used for preparing the aqueous medium, for example, ion-exchanged water can be used. The dispersion liquid is preferably prepared using 100 parts by mass or more of water per 100 parts by mass of the polymerizable monomer. When the amount of water used is 100 parts by mass or more, oil droplets (polymer particles) can be easily formed without causing oil-water inversion.

- Dispersion stabilizer A dispersion stabilizer plays a role as a dispersion stabilizer for suspended particles present in a suspension in the granulation process. Types of inorganic compounds used as dispersion stabilizers include hydroxyapatite, tribasic calcium phosphate, dibasic calcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, calcium carbonate, magnesium carbonate, calcium hydroxide, magnesium hydroxide, Examples include aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate, bentonite, silica, and alumina. Examples of the organic compound used as a dispersion stabilizer include polyvinyl alcohol, gelatin, methylcellulose, methylhydroxypropylcellulose, ethylcellulose, sodium salt of carboxymethylcellulose, polyacrylic acid and its salt, starch, and the like. Further, a surfactant may be used for fine dispersion of these dispersion stabilizers. This is to promote the initial action of the dispersion stabilizer. Examples of the surfactant include sodium dodecylbenzene sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, potassium stearate, and calcium oleate. When using an inorganic compound as a dispersion stabilizer, a commercially available one may be used as is, but in order to obtain finer particles, the above-mentioned inorganic compound may be produced in an aqueous medium and used. For example, in the case of calcium phosphates such as hydroxyapatite and tricalcium phosphate, it is preferable to mix the phosphate aqueous solution and the calcium salt aqueous solution under high stirring.

[Granulation process]
A suspension is prepared by dispersing a liquid mixture containing a binder resin, a fatty acid metal salt, and an organic solvent in the aqueous medium. That is, by the granulation process, a suspension containing a dispersion stabilizer and suspended particles made of the mixed liquid can be obtained.

When granulating the suspended particles, a stirring device such as a TK homomixer (trade name, manufactured by Tokushu Kika Kogyo) can be used.

The water-soluble metal salt of the present invention may be added during this granulation step.

[Solvent removal process]
By removing the organic solvent contained in the suspended particles in the suspension, polymer particles containing the binder resin can be generated, and a dispersion in which the polymer particles are dispersed can be obtained. .

As the method for removing the solvent, known methods such as removing the solvent by heating, removing the solvent by reducing pressure, and a combination thereof can be used.

The water-soluble metal salt of the present invention may be added in this desolvation step.

[Alkali treatment process]
After adding the water-soluble metal salt, the temperature of the dispersion liquid in which the polymer particles are dispersed is set to be higher than the Tg of the binder resin, and the pH is set to 7.5 or more and less than 10.0, in order to make the surface of the toner particles irregular. Perform an alkali treatment process to

Further, in the alkali treatment step, it is desirable from the viewpoint of improving durability to add resin particles to fix the resin particles to the surface of the toner base particles. From the viewpoint of transferability, it is more preferable that the resin particles to be fixed contain the polymer A having the monovalent group a represented by the above-mentioned formula (1).

[Washing, filtration and drying process]
In order to remove the dispersion stabilizer adhering to the surface of the polymer particles, the dispersion containing the polymer particles can also be treated with acid or alkali. At this time, the polymer particles are separated into a liquid phase using a general solid-liquid separation method, but in order to completely remove the acid or alkali and the dispersion stabilizer component dissolved therein, water is added again to form the polymer. Wash particles. This washing process is repeated several times, and after sufficient washing has been performed, solid-liquid separation is performed again to obtain toner particles. The obtained toner particles can be dried by known drying means, if necessary.

[External addition process]
The external additives exemplified in the first embodiment can be used similarly.

- Toner particles As explained in the first form, this can be applied to various developing methods.

The measurement method used in each example below will be explained.

- Measurement of glass transition temperature (Tg) of polymer and binder resin Tg of the polymer and binder resin was measured using a differential scanning calorimeter (DSC measuring device).

A differential scanning calorimeter used was a differential scanning calorimeter "Q1000" (trade name, manufactured by TA Instruments), and the measurement was performed in accordance with ASTM D3418-82 as follows. 3 mg of the measurement sample (polymer and binder resin) was precisely weighed. It was placed in an aluminum pan, and an empty aluminum pan was used as a control. After maintaining equilibrium at 20°C for 5 minutes, measurements were performed at a temperature increase rate of 10°C/min within the measurement range of 20°C to 180°C. Note that the glass transition temperature was determined by the midpoint method.

・Measurement of the weight average particle diameter (D4) of the toner particles The weight average particle diameter (D4) of the toner particles was measured using a precision particle size distribution measuring device "Coulter Counter Multisizer 3" using a pore electrical resistance method equipped with a 100 μm aperture tube. (registered trademark, manufactured by Beckman Coulter) and the attached dedicated software "Beckman Coulter Multisizer 3 Version 3.51" (manufactured by Beckman Coulter) for setting measurement conditions and analyzing measurement data. The calculation was made by measuring with 25,000 channels and analyzing the measurement data.

The electrolytic aqueous solution used in the measurement can be one in which special grade sodium chloride is dissolved in ion-exchanged water to have a concentration of about 1% by mass, such as "ISOTON II" (manufactured by Beckman Coulter).

In addition, before carrying out the measurement and analysis, the settings of the dedicated software were made as follows.

On the "Change standard measurement method (SOM) screen" of the dedicated software, set the total count in control mode to 50,000 particles, set the number of measurements to 1, and set the Kd value to "standard particle 10.0 μm" (Beckman Coulter) Set the value obtained using By pressing the threshold/noise level measurement button, the threshold and noise level are automatically set. Also, set the current to 1600 μA, the gain to 2, the electrolyte to ISOTON II, and check the aperture tube flush after measurement.

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

The specific measurement method is as follows.
(1) Approximately 200 ml of the above electrolyte aqueous solution is placed in a 250 ml round bottom glass beaker exclusively for Multisizer 3, set on a sample stand, and stirred with a stirrer rod counterclockwise at 24 revolutions/second. Then, use the analysis software's ``aperture flush'' function to remove dirt and air bubbles from inside the aperture tube.
(2) Pour about 30 ml of the above electrolytic aqueous solution into a 100 ml glass flat-bottomed beaker, and add "Contaminon N" as a dispersant (precision measurement of pH 7 consisting of nonionic surfactant, anionic surfactant, and organic builder). Approximately 0.3 ml of a diluted solution prepared by diluting a 10% by mass aqueous solution of a neutral detergent for cleaning utensils (manufactured by Wako Pure Chemical Industries, Ltd.) by 3 times by mass with ion-exchanged water is added.
(3) Two oscillators with an oscillation frequency of 50 kHz are built in with their phases shifted by 180 degrees, and placed in the water tank of an ultrasonic dispersion device "Ultrasonic Dispension System Tetora 150" (manufactured by Nikkaki Bios Co., Ltd.) with an electrical output of 120 W. A fixed amount of ion-exchanged water is poured into the tank, and approximately 2 ml of the contaminon N is added to the water tank.
(4) Set the beaker of (2) above in the beaker fixing hole of the ultrasonic disperser, and operate the ultrasonic disperser. Then, the height position of the beaker is adjusted so that the resonance state of the liquid level of the electrolytic aqueous solution in the beaker is maximized.
(5) While the electrolytic aqueous solution in the beaker of (4) is irradiated with ultrasonic waves, about 10 mg of core particles or toner particles are added little by little to the electrolytic aqueous solution and dispersed. Then, the ultrasonic dispersion treatment is continued for another 60 seconds. Incidentally, during the ultrasonic dispersion, the water temperature in the water tank is appropriately adjusted to be 10° C. or more and 40° C. or less.
(6) Using a pipette, drop the aqueous electrolyte solution of (5) in which toner is dispersed into the round bottom beaker of (1) placed in the sample stand, and adjust the measured concentration to approximately 5%. . Then, the measurement is continued until the number of measured particles reaches 50,000.
(7) Analyze the measurement data using the dedicated software attached to the device and calculate the weight average particle diameter (D4). In addition, when the graph/volume % is set in the dedicated software, the "average diameter" on the analysis/volume statistics (arithmetic mean) screen is the weight average particle diameter (D4).

・Measurement of the volume-based D50 of the resin particles contained in the resin particle dispersion The volume-based median diameter (D50) of the resin particles contained in the resin particle dispersion was measured using Zetasizer Nano-ZS (manufactured by MALVERN). It is calculated by measuring the particle size using dynamic light scattering (DLS).

First, turn on the device and wait 30 minutes for the laser to stabilize. Then launch the Zetasizer software.

Select Manual from the Measure menu and enter measurement details as shown below.
Measurement mode: Particle size Material: Polystyrene latex (RI: 1.59, Absorption: 0.01)
Dispersant: Water (Temperature: 25°C, Viscosity: 0.8872cP, RI: 1.330)
Temperature: 25.0℃
Cell: Clear disposable zeta cell
Measurement duration: Automatic

The sample is prepared by diluting it with water to a concentration of 0.50% by mass, and is filled into a disposable capillary cell (DTS1060), and the cell is inserted into the cell holder of the device.

When the above preparations are completed, press the Start button on the measurement display screen to begin measurement.

D50 is calculated based on volume-based particle size distribution data obtained by converting the light intensity distribution obtained from DLS measurement using Mie theory.

Next, the manufacturing method of each resin used in each example will be explained.

<Manufacture of binder resin>
(Production example of polyester resin 1)
The following items were charged into a reaction vessel equipped with a stirrer, condenser, thermometer, cooling tube, nitrogen introduction tube, and stirrer.
・1,2-propanediol: 847 parts by mass ・Terephthalic acid dimethyl ester: 861 parts by mass ・1,6-hexanedioic acid: 212 parts by mass ・Tetrabutoxy titanate (condensation catalyst): 3 parts by mass At 170°C under nitrogen stream The reaction was continued for 7 hours while the methanol produced was distilled off. Then, while gradually raising the temperature to 240° C., the mixture was allowed to react for 5 hours while distilling off the produced propylene glycol and water under a nitrogen stream. After the reaction was further carried out under a reduced pressure of 20 mmHg, it was taken out. After cooling the resin taken out to room temperature, it was crushed and granulated to obtain polyester resin 1. The Tg of the polyester resin 1 was 44°C.

<Manufacture of polar resin>
(Production example of polyester resin 2)
Terephthalic acid 43.00 mol parts Trimellitic acid 1.30 mol parts Adduct of bisphenol A with 2 mol of propylene oxide 32.00 mol parts Ethylene glycol 100 parts by mass of a mixture mixed at a charging ratio of 23.70 mol parts 0.55 parts by mass of tin (2-ethylhexanoic acid) was placed in a 6 liter four-necked flask equipped with a nitrogen inlet tube, dehydration tube, stirrer and thermocouple, and the mixture was heated at 200°C for 6 hours under a nitrogen atmosphere. Made it react. Furthermore, trimellitic anhydride was added at 210° C., and the reaction was carried out under a reduced pressure of 40 kPa, and the reaction was continued until the weight average molecular weight (Mw) reached 12,000. The obtained resin will be referred to as polyester resin 2.

Next, a method for producing each resin particle dispersion used in each example will be explained.

<Production of resin particle dispersion>
- Production example of polymer A-1 18 g of 2,4-dihydroxybenzoic acid was dissolved in 150 mL of methanol, 36.9 g of potassium carbonate was added, and the mixture was heated to 65°C. A mixed solution of 18.7 g of 4-(chloromethyl)styrene and 100 mL of methanol was added dropwise to this reaction solution, and the mixture was reacted at 65° C. for 3 hours. After cooling the reaction solution, it was filtered, and the filtrate was concentrated to obtain a crude product. The crude product was dispersed in 1.5 L of water at pH=2 and extracted with ethyl acetate. Thereafter, it was washed with water, dried over magnesium sulfate, and ethyl acetate was distilled off under reduced pressure to obtain a precipitate. The precipitate was washed with hexane and then purified by recrystallization from toluene and ethyl acetate to obtain 20.1 g of a polymerizable monomer represented by the following formula (2).

9.9 g of the polymerizable monomer shown in formula (2) and 60.1 g of styrene were dissolved in 42.0 ml of DMF (N,N-dimethylformamide), stirred for 1 hour while bubbling with nitrogen, and then heated to 110°C. Heated. A mixed solution of 2.1 g of tert-butylperoxyisopropyl monocarbonate (manufactured by NOF Corporation, trade name: Perbutyl I) and 42 ml of toluene was added dropwise to this reaction solution as an initiator. The reaction was further carried out at 110°C for 4 hours. Thereafter, the reaction solution was cooled and added dropwise to 1 L of methanol to obtain a precipitate. After dissolving the obtained precipitate in 120 ml of THF, it was added dropwise to 1.80 L of methanol to precipitate a white precipitate, filtered, and dried at 90° C. under reduced pressure to obtain 63.2 g of polymer A-1. Ta. The content (μmol number per 1 g of resin) of the component derived from the monovalent group a represented by formula (1) in Polymer A-1 was 526 μmol/g.

・Production example of resin particle dispersion 1 Into a reaction vessel equipped with a stirrer, a condenser, a thermometer, and a nitrogen introduction tube, 200.0 parts by mass of methyl ethyl ketone was charged, and 100.0 parts by mass of polymer A-1 was added and dissolved. did. Next, a 1.0 mol/L aqueous potassium hydroxide solution was slowly added, and after stirring for 10 minutes, 500.0 parts by mass of ion-exchanged water was slowly added dropwise to emulsify. The obtained emulsion was distilled under reduced pressure to remove the solvent, and ion-exchanged water was added to adjust the resin concentration to 20%, thereby obtaining a resin particle dispersion 1.

The average particle size of the A-1 particles in the resulting resin particle dispersion 1 was 37 nm.

(Manufacture of polyester resin 3)
The following monomers were charged into a reaction vessel equipped with a stirrer, a condenser, a thermometer, and a nitrogen introduction tube, and 0.03 parts by mass of tetrabutoxy titanate was added as an esterification catalyst, and the temperature was raised to 210°C under a nitrogen atmosphere. The reaction was carried out for 5 hours while stirring.
Bisphenol A-propylene oxide 2 mole 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 Department

Next, while reducing the pressure inside the reaction vessel to 5 to 20 mmHg, the reaction was further carried out for 5 hours to obtain polyester resin 3. The Tg of polyester resin 3 was 66°C.

(Preparation of resin particle dispersion 2)
100.0 parts by mass of the obtained polyester resin 3, 45.0 parts by mass of methyl ethyl ketone, and 45.0 parts by mass of tetrahydrofuran were placed in a reaction vessel equipped with a stirrer, a condenser, a thermometer, and a nitrogen introduction tube, and the mixture was heated to 80°C. It was heated and dissolved.

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

After cooling, ion-exchanged water was added to the obtained water dispersion to adjust the resin concentration in the dispersion to 20%. This was designated as resin fine particle dispersion liquid 2. The average particle diameter of the three polyester resin particles in the resulting resin particle dispersion 2 was 48 nm.

Next, Table 1 shows the fatty acid metal salts used in each example.

Next, Table 2 shows the water-soluble metal salts used in each example.

[Example 1]
<Manufacture of toner 1>
(Preparation of aqueous medium containing dispersion stabilizer)
100.00 parts by mass of ion-exchanged water, 2.00 parts by mass of sodium phosphate, and 0.90 parts by mass of 10% by mass hydrochloric acid were added to a granulation tank to prepare a sodium phosphate aqueous solution, and heated to 50°C. did. To this granulation tank, a calcium chloride aqueous solution prepared by dissolving 1.2 parts by mass of calcium chloride hexahydrate in 8.20 parts by mass of ion-exchanged water was added, and a TK homomixer (trade name, Tokushu Kika Kogyo) was added. The mixture was stirred for 30 minutes at a circumferential speed of 25 m/s. Thereby, an aqueous medium containing (fine particles of) calcium phosphate as a dispersion stabilizer was obtained (aqueous medium preparation step).

(Preparation of pigment dispersion composition)
Polymerizable monomer: Styrene 39.00 parts by mass Colorant: C.I. I. Pigment Blue 15:3 6.50 parts by mass Fatty acid metal salt 1 0.13 parts by mass The above materials were introduced into an attritor (manufactured by Nippon Coke Co., Ltd.) and heated at 25°C at 200 rpm using zirconia beads with a radius of 1.25 mm. The mixture was stirred for 180 minutes to prepare a pigment dispersion composition.

(Preparation of colorant-containing composition)
The following materials were put into the same container, and mixed and dispersed at a circumferential speed of 20 m/s using a TK homomixer (trade name, manufactured by Tokushu Kika Kogyo).
- The above pigment dispersion composition 45.63 parts by mass - Polymerizable monomer: styrene 33.00 parts by mass - Polymerizable monomer: n-butyl acrylate 28.00 parts by mass - Polar resin: Polyester resin 2 2.00 Parts by Mass After further heating to 60° C., 10.00 parts by mass of a mold release agent: behenyl behenate was added, followed by dispersion and mixing for 30 minutes to prepare a colorant-containing composition.

(Preparation of suspended particles of polymerizable monomer composition)
The above coloring agent-containing composition was added to a dispersion containing calcium phosphate fine particles, and heated at a temperature of 60° C. under a nitrogen atmosphere at a circumferential speed of 30 m/s using a TK type homomixer (trade name, manufactured by Tokushu Kika Kogyo Co., Ltd.). It was stirred with To this, 2.50 parts by mass of a polymerization initiator t-hexyl peroxypivalate (manufactured by NOF Corporation, trade name "Perhexyl PV", molecular weight: 202, 10 hour half-life temperature: 53.2 ° C.) was added, A suspension in which polymerizable monomer composition particles were dispersed was prepared (granulation step).

(Preparation of toner particles 1)
The suspension of the polymerizable monomer composition particles was transferred to another tank, heated to 70°C while stirring with a paddle stirring blade, reacted for 4 hours, and 0.10 parts by mass of aluminum chloride was added. (Water-soluble metal salt addition step). At this time, the pH of the suspension before addition of aluminum chloride was 5.3. Furthermore, after reacting under the same conditions for 1 hour, the temperature was further raised to 80° C., and the reaction was continued for 6 hours (heating step). As a result, a dispersion liquid (polymerization slurry) in which polymer particles including toner particles 1 were dispersed was obtained (suspension polymerization step). At this time, the pH of the polymerization slurry was 5.0.

After the polymerization step was completed, 120° C. steam was started to be supplied to the polymerization slurry at a flow rate of 5 kg/hr. After the start of water vapor supply, distillation was started when the temperature reached 98° C., and distillation was carried out for 8 hours (distillation step).

After the distillation step, a 7.0% aqueous sodium carbonate solution was added so that the pH of the polymerization slurry became 8.5, and the mixture was maintained at 80° C. for 1 hour (alkali treatment step).

Simultaneously with the start of the alkali treatment step, 1.25 parts by mass of resin particle dispersion 1 was added to 100 parts by mass of solid content in the polymerization slurry to fix resin particles A-1 to the surface of the polymer particles. Ta.

After cooling, hydrochloric acid was added to adjust the pH to 1.4, and the mixture was stirred for 2 hours to dissolve poorly water-soluble inorganic fine particles on the surface of the toner particles. The toner particle dispersion was filtered, washed with water, and then dried at a temperature of 40° C. for 48 hours to obtain toner particles 1 (washing/filtration/drying step).

(Preparation of toner particles 1 having inorganic fine powder on the surface)
1.50 parts by mass of an inorganic fine powder was mixed with 100.0 parts by mass of the above toner particles at 3000 rpm (min-1) for 15 minutes using a Henschel mixer (manufactured by Mitsui Miike Kakoki Co., Ltd.). Toner particles 1 having inorganic fine powder on the surface were obtained (external addition step).

Note that, in order to distinguish from the toner particles 1 before applying the inorganic fine powder, the toner particles 1 having the above-mentioned inorganic fine powder on the surface will be hereinafter referred to as toner 1. The inorganic fine powder is hydrophobic silica that is treated with dimethyl silicone oil (20% by mass), which is a fluidity improver, and triboelectrically charged to the same polarity (negative polarity) as the toner particles 1 before being coated with the inorganic fine powder. Fine particles (number average particle size of primary particles: 10 nm, BET specific surface area: 170 m ² /g) were used.

[Example 5]
<Preparation of toner 5>
(Preparation of suspended particles of polymerizable monomer composition)
In the same manner as in Example 1, suspended particles of a polymerizable monomer composition were prepared.

(Preparation of toner particles 5)
The suspension of the polymerizable monomer composition particles was transferred to another tank, heated to 70°C while stirring with a paddle stirring blade, reacted for 1 hour, and 0.10 parts by mass of aluminum chloride was added. (Water-soluble metal salt addition step). At this time, the pH of the suspension before addition of aluminum chloride was 5.3. Furthermore, after reacting under the same conditions for 4 hours, the temperature was further raised to 80° C., and the reaction was continued for 6 hours (heating step). As a result, a dispersion liquid (polymerization slurry) in which polymer particles including toner particles 5 were dispersed was obtained (suspension polymerization step).

(Preparation of toner 5)
After the polymerization step was completed, the same distillation step, alkali treatment step, washing/filtration/drying step, and external addition step as in Example 1 were performed to obtain Toner 5.

[Example 6]
<Preparation of toner 6>
(Preparation of aqueous medium containing dispersion stabilizer)
100.00 parts by mass of ion-exchanged water, 2.00 parts by mass of sodium phosphate, and 0.90 parts by mass of 10% by mass hydrochloric acid were added to a granulation tank to prepare a sodium phosphate aqueous solution, and heated to 50°C. did. To this granulation tank, a calcium chloride aqueous solution prepared by dissolving 1.20 parts by mass of calcium chloride hexahydrate in 8.20 parts by mass of ion-exchanged water was added, and a TK homomixer (trade name, Tokushu Kika Kogyo) was added. The mixture was stirred for 30 minutes at a circumferential speed of 25 m/s. As a result, an aqueous medium containing (fine particles of) calcium phosphate as poorly water-soluble inorganic fine particles was obtained (aqueous medium preparation step). The pH of the aqueous medium was 5.5. Subsequently, 0.10 parts by mass of aluminum chloride was added to the aqueous medium (water-soluble metal salt addition step).

Toner 6 was obtained by carrying out the same operation as in Example 1 except for using the aqueous medium to which aluminum chloride was added.

[Example 7]
<Manufacture of toner 7>
(Preparation of additionally added dispersion stabilizer)
20.00 parts by mass of ion-exchanged water, 0.40 parts by mass of sodium phosphate, and 0.18 parts by mass of 10% by mass hydrochloric acid were added to a granulation tank to prepare a sodium phosphate aqueous solution, and heated to 50°C. did. To this granulation tank, a calcium chloride aqueous solution prepared by dissolving 0.24 parts by mass of calcium chloride hexahydrate in 1.64 parts by mass of ion-exchanged water was added, and a TK homomixer (trade name, Tokushu Kika Kogyo) was added. The mixture was stirred for 30 minutes at a circumferential speed of 25 m/s. Thereafter, 0.10 parts by mass of aluminum chloride was added. At this time, the pH of the additionally added dispersion stabilizer before adding aluminum chloride was 5.5.

As a result, an additionally added dispersion stabilizer containing (fine particles of) calcium phosphate as poorly water-soluble inorganic fine particles was obtained.

(Preparation of suspended particles of polymerizable monomer composition)
Suspended particles of the polymerizable monomer composition were prepared in the same manner as in Example 1 (granulation step).

(Preparation of toner 7)
Transfer the suspension of the polymerizable monomer composition particles to another tank, raise the temperature to 70°C while stirring with a paddle stirring blade, react for 5 hours, and then further raise the temperature to 80°C, After reacting for 4 hours, the additional dispersion stabilizer was added. The pH of the suspension before adding the additional dispersion stabilizer was 5.3. Furthermore, after reacting under the same conditions for 1 hour, the temperature was further raised to 80° C., and the reaction was continued for 6 hours (heating step). As a result, a dispersion liquid (polymerization slurry) in which polymer particles including toner particles 7 were dispersed was obtained (suspension polymerization step). At this time, the pH of the polymerization slurry was 5.0.

The polymerization slurry was subjected to the same operation as in Example 1 to obtain Toner 7.

[Examples 18-20, 26, 27, 32, 33, Comparative Examples 1-6, 9]
Toner particles 18 to 20, 26, and 27 were produced in the same manner as above, except that the process conditions and the fatty acid metal salts and water-soluble metal salts used were changed as shown in Table 3. , 32-39, and 42 were prepared.

[Comparative example 7]
In preparing the aqueous medium containing the dispersion stabilizer in Example 1, the same procedure as in Example 1 was carried out except that the amount of 10% by mass hydrochloric acid used was 1.20 parts by mass. As a result, the polymer particles coalesced and became coarse during the distillation process, and toner 40 could not be obtained.

[Comparative example 8]
Toner 41 was prepared in the same manner as in Example 1, except that in the preparation of the aqueous medium containing the dispersion stabilizer in Example 1, the amount of 10% by mass hydrochloric acid used was 0.55 parts by mass.

[Example 2]
<Manufacture of toner 2>
(Preparation of binder resin solution)
Binder resin solution 1 was prepared by adding 50 parts by mass of ethyl acetate into an airtight container equipped with a stirring blade and stirring at 100 rpm, and then adding 50 parts by mass of the above polyester resin 1 and stirring at room temperature for 3 days. .

(Example of manufacturing release agent dispersion)
・Carnauba wax (melting point 83°C): 18 parts by mass ・Ethyl acetate: 82 parts by mass Pour the above into a container with a stirring blade and heat the system to 70°C to dissolve carnauba wax in ethyl acetate. Ta.

Then, the system was gradually cooled while being gently stirred at 100 rpm, and was cooled down to 30° C. over 2 hours to obtain a milky white liquid.

This solution was placed in a heat-resistant container together with 20 parts by mass of 1 mm glass beads, and dispersed for 3 hours using a paint shaker. The glass beads were removed using a nylon mesh to obtain wax dispersion 1.

(Production example of colorant dispersion)
・Polyester resin 1: 20 parts by mass ・Cu phthalocyanine (Pigment Blue 15:3): 20 parts by mass ・Fatty acid metal salt 1: 0.52 parts by mass ・Ethyl acetate: 59.48 parts by mass Thoroughly premix the above materials in a container. After that, the mixture was uniformly dispersed and mixed for about 4 hours using an attritor (manufactured by Mitsui Miike Kakoki) while maintaining the temperature at 20° C. or lower to obtain Colorant Dispersion 1.

(Preparation of mixed solution)
Wax dispersion liquid 1: 50 parts by mass (Carnauba WAX content: 18%)
Colorant dispersion 1: 25 parts by mass (pigment content: 20%, resin content: 20%, fatty acid metal salt content: 0.52%)
Binder resin solution 1: 160 parts by mass (resin content: 50%)
Ethyl acetate: 15 parts by mass The above solution was poured into a container, and homodisper (manufactured by Tokushu Kika Kogyo Co., Ltd.) was heated for 2000 r.
A mixed solution was prepared by stirring and dispersing at pm for 5 minutes.

(Preparation of aqueous medium containing dispersion stabilizer)
100.00 parts by mass of ion-exchanged water, 2.00 parts by mass of sodium phosphate, and 0.90 parts by mass of 10% by mass hydrochloric acid were added to a granulation tank to prepare a sodium phosphate aqueous solution, and heated to 50°C. did. To this granulation tank, a calcium chloride aqueous solution prepared by dissolving 1.2 parts by mass of calcium chloride hexahydrate in 8.20 parts by mass of ion-exchanged water was added, and a TK homomixer (trade name, Tokushu Kika Kogyo) was added. The mixture was stirred for 30 minutes at a circumferential speed of 25 m/s. Thereby, an aqueous medium containing (fine particles of) calcium phosphate as a dispersion stabilizer was obtained (aqueous medium preparation step).

(Preparation of suspension containing suspended particles)
120 parts by mass of the mixed liquid was put into the aqueous medium and stirred at a circumferential speed of 30 m/s using a TK homomixer (trade name, manufactured by Tokushu Kika Kogyo) to obtain a suspension containing suspended particles. Obtained.

(Addition process of water-soluble metal salt)
The suspension was transferred to another tank, heated to 70° C. while stirring with a paddle stirring blade, and 0.10 parts by mass of aluminum chloride was added (water-soluble metal salt addition step). At this time, the pH of the suspension before addition of aluminum chloride was 5.3.

(Desolvation step)
The suspension to which the water-soluble metal salt had been added was stirred at a rotation speed of 150 revolutions/min with a paddle stirring blade, and the solvent was removed over 5 hours at 70°C and under reduced pressure to 500 mgHg. A dispersion liquid in which the combined particles were dispersed was obtained.

After the solvent removal was completed, a 7.0% aqueous sodium carbonate solution was added so that the pH of the dispersion became 8.5, and the mixture was maintained at 70° C. for 1 hour (alkali treatment step).

Simultaneously with the start of the alkali treatment step, 1.25 parts by mass of resin particle dispersion 1 was added to 100 parts by mass of solid content in the polymerization slurry to fix resin particles A-1 to the surface of the polymer particles. Ta.

Thereafter, after cooling, hydrochloric acid was added to adjust the pH to 1.4, and the mixture was stirred for 2 hours to dissolve the poorly water-soluble inorganic fine particles on the surface of the toner particles. The toner particle dispersion was filtered, washed with water, and then dried at a temperature of 40° C. for 48 hours to obtain toner particles 2 (washing/filtration/drying step).

(Preparation of toner particles 2 having inorganic fine powder on the surface)
1.50 parts by mass of inorganic fine powder was mixed with 100.0 parts by mass of the above toner particles 2 at 3000 rpm (min ^-1 ) for 15 minutes using a Henschel mixer (manufactured by Mitsui Miike Kakoki Co., Ltd.). Toner particles 2 having inorganic fine powder on the surface were obtained (external addition step).

Note that, in order to distinguish from the toner particles 2 before applying the inorganic fine powder, the toner particles 2 having the above-mentioned inorganic fine powder on the surface will be referred to as toner 2 hereinafter. The inorganic fine powder is hydrophobic silica that is treated with dimethyl silicone oil (20% by mass), which is a fluidity improver, and triboelectrically charged to the same polarity (negative polarity) as the toner particles 2 before the inorganic fine powder is applied. Fine particles (number average particle size of primary particles: 10 nm, BET specific surface area: 170 m ² /g) were used.

[Examples 3, 4, 8-15, 21-25, 28-31]
Toner Particles 2 and Toner 2 were manufactured in the same manner as Toners 3, 4, 8 to 15, except that the process conditions and the fatty acid metal salts and water-soluble metal salts used were changed as shown in Table 4. , 21-25, 28-31 were prepared.

In Table 4, examples in which the timing of alkali treatment is "after" the desolvation step are in the second embodiment of the present invention, examples in which the timing is "simultaneously" are in the third embodiment of the present invention, and examples in which the timing is "before" are in the present invention. This corresponds to the fourth form of the invention.

[Example 16]
Toner 16 was prepared in the same manner as in Example 4, except that in preparing the aqueous medium containing the dispersion stabilizer in Example 4, the amount of 10% by mass hydrochloric acid used was 1.10 parts by mass.

[Example 17]
Toner 17 was prepared in the same manner as in Example 4, except that in preparing the aqueous medium containing the dispersion stabilizer in Example 4, the amount of 10% by mass hydrochloric acid used was 0.6 parts by mass.

The obtained toners 1 to 42 were evaluated as shown below.

<Cleanability evaluation>
The cleaning performance was evaluated using a partially modified commercially available color laser printer LBP712Ci (manufactured by Canon). In the modification, the cleaning blade was adjusted so that the angle of contact with the surface of the electrophotographic photoreceptor was 20° and the amount of penetration of the cleaning blade was 0.2 mm.

The above toner cartridge was filled with 170 g of toner. Then, after being left in a low temperature, low humidity (10° C./15% RH) environment for 24 hours, 20,000 images with a print ratio of 1.0% were output. The cleaning performance was evaluated based on the occurrence of toner slipping through the cleaning blade when a solid image was output at a high printing rate of 5.0% at the initial stage and after 20,000 sheets of image output (image formation). The evaluation ranks are as follows. The cleaning performance improves in the order of D, C, B, and A. Rank C or higher is desirable in order to obtain the effects of the present invention. The evaluation results are shown in Table 5.
A: No toner slip-through.
B: Although it does not appear in the image, there is some toner slipping through. There is no risk of contamination of charging parts.
C: Although it does not appear in the image, there is some toner slipping through. There is a risk of contamination of charging parts.
D: Toner slip-through that appears in the image.

<Evaluation of coarsening>
The coarsening was evaluated based on the absolute value of the change in D4 of the polymer particles before and after the distillation step or the solvent removal step. The evaluation criteria are as follows. The results are shown in Table 5.
A: The absolute value of the change in D4 is less than 0.10 μm B: The absolute value of the change in D4 is 0.10 μm or more and less than 0.15 μm C: The absolute value of the change in D4 is 0.15 μm or more and less than 0.20 μm D: D4 The absolute value of the change is 0.20μm or more

<Durability (streaks)>
Durability was evaluated using a partially modified HP Color LaserJet 3525dn, which is a commercially available color laser printer. The modification was made so that it would work even if only one color process cartridge was installed. Additionally, the fuser was modified so that the temperature could be changed to any desired temperature.

After removing the toner from the black toner process cartridge installed in this color laser printer and cleaning the inside with air blow, each toner (300g) is introduced into the process cartridge, and the toner is refilled. The process cartridge was installed in a color laser printer, and the following image evaluations were performed. Specific image evaluation items are as follows.

Printed 50,000 images with a printing rate of 0.5% for horizontal lines under normal temperature and normal humidity environment (temperature 23℃/humidity 60%RH) and high temperature and high humidity environment (temperature 33℃/humidity 85%RH). After the out test, a halftone image (toner coverage: 0.6 mg/cm ² ) was printed out on LETTER size XEROX 4200 paper (manufactured by XEROX, 75 g/m ² ), and development streaks were evaluated. .
A: No development streaks occur B: Development streaks occur in 1 to 2 locations C: Development streaks occur in 3 to 4 locations D: Development streaks occur in 5 to 6 locations E: Development streaks occur in 7 or more locations; Or a width of 0.5mm or more occurs.

<Transferability>
As the image forming apparatus, a modified LBP-7700C (manufactured by Canon), which is a commercially available laser printer, and a modified toner cartridge 323 (cyan) (manufactured by Canon), which is a process cartridge, were used.

The modification was made so that the process speed was 240 mm/sec by changing the internal gears. Furthermore, this modified cartridge was modified so that the surfaces of the toner supply roller and the toner carrying roller move in the same direction at the contact portion with the toner carrying roller by changing and adding gears inside the cartridge. Note that the circumferential speed of the toner supply roller was adjusted to 160% based on the toner carrying roller. Further, the product toner was extracted from the inside of the cartridge, and after cleaning with air blow, 160 g of toner was filled.

The process cartridge filled with toner was left in a high temperature, high humidity environment (40° C./95% RH) for 15 days.

Images with a printing rate of 1% were output on 20,000 sheets of Canon color laser copy paper (A4: 81.4 g/m ² ). After that, the entire solid image is output, the device is stopped during the transfer from the photoconductor to the intermediate transfer body, and the toner amount M1 (mg/cm ² ) on the photoconductor before the transfer process and the amount on the photoconductor after the transfer process are determined. The applied toner amount M2 (mg/cm ² ) was measured. From the obtained amount of applied toner, (M1-M2)×100/M1 was defined as the transfer efficiency (%).
A: Transfer efficiency of 95% or more B: Transfer efficiency of 90% or more and less than 95% C: Transfer efficiency of 85% or more and less than 90% D: Transfer efficiency of less than 85%

Claims (11)

Dispersing a polymerizable monomer composition containing a polymerizable monomer and a fatty acid metal salt in an aqueous medium containing a dispersion stabilizer to prepare a suspension;
adding a water-soluble metal salt to the suspension;
Polymerizing the polymerizable monomer contained in suspended particles in the suspension to which the water-soluble metal salt is added, producing polymer particles containing the polymer produced by the polymerization, obtaining a dispersion liquid in which particles are dispersed, and
Alkaline treatment in which the dispersion is heated to a temperature equal to or higher than the glass transition point of the polymer contained in the polymer particles, and the pH of the dispersion is maintained under conditions of 7.5 or more and 10.0 or less. process,
A method for producing a toner having the following steps:
The water-soluble metal salt is a salt of a divalent or higher valent metal,
The pH of the suspension before adding the water-soluble metal salt is 4.0 or more and less than 6.5.
A method for producing a toner characterized by the following. A step of preparing a suspension by dispersing a mixed solution prepared by mixing a binder resin, a fatty acid metal salt, and an organic solvent in an aqueous medium containing a dispersion stabilizer;
adding a water-soluble metal salt to the suspension;
The organic solvent contained in the suspended particles in the suspension to which the water-soluble metal salt is added is removed to produce polymer particles containing the binder resin, and the polymer particles are dispersed. obtaining a dispersion liquid, and
an alkali treatment step in which the dispersion is heated to a temperature equal to or higher than the glass transition point of the binder resin, and the pH of the dispersion is maintained under conditions of 7.5 or more and 10.0 or less;
A method for producing a toner having the following steps:
The water-soluble metal salt is a salt of a divalent or higher valent metal,
The pH of the suspension before adding the water-soluble metal salt is 4.0 or more and less than 6.5.
A method for manufacturing a toner characterized by the following. A step of preparing a suspension by dispersing a liquid mixture prepared by mixing a binder resin, a fatty acid metal salt, and an organic solvent in an aqueous medium containing a dispersion stabilizer;
adding a water-soluble metal salt to the suspension; and
The suspension to which the water-soluble metal salt has been added is heated to a temperature equal to or higher than the glass transition point of the binder resin, and the pH of the suspension is set to 7.5 or more and 10.0 or less. The organic solvent contained in the suspended particles in the suspension is removed while carrying out an alkali treatment step in which the particles are held in a silica to form polymer particles containing the binder resin, and the polymer particles are dispersed. obtaining a dispersion liquid,
A method for producing a toner having the following steps:
The water-soluble metal salt is a salt of a divalent or higher valent metal,
The pH of the suspension before adding the water-soluble metal salt is 4.0 or more and less than 6.5.
A method for manufacturing a toner characterized by the following. A step of preparing a suspension by dispersing a liquid mixture prepared by mixing a binder resin, a fatty acid metal salt, and an organic solvent in an aqueous medium containing a dispersion stabilizer;
adding a water-soluble metal salt to the suspension;
The suspension to which the water-soluble metal salt has been added is heated to a temperature equal to or higher than the glass transition point of the binder resin, and the pH of the suspension is set to 7.5 or more and 10.0 or less. an alkaline treatment step, in which the
After the step of heating to a temperature equal to or higher than the glass transition point of the binder resin and maintaining the pH of the suspension under conditions of 7.5 or more and 10.0 or less, the suspension in the suspension removing the organic solvent contained in the particles to produce polymer particles containing the binder resin to obtain a dispersion in which the polymer particles are dispersed;
A method for producing a toner having the following steps:
The water-soluble metal salt is a salt of a divalent or higher valent metal,
The pH of the suspension before adding the water-soluble metal salt is 4.0 or more and less than 6.5.
A method for manufacturing a toner characterized by the following. The method for producing a toner according to any one of claims 2 to 4, wherein the organic solvent is an organic solvent that can dissolve the binder resin and fatty acid metal salt. The method for producing a toner according to any one of claims 1 to 5, wherein the fatty acid metal salt contains a polyvalent metal of divalent or higher valence. 7. The toner manufacturing method according to claim 6, wherein the polyvalent metal having a valence of 2 or more is a metal having a valence of 3 or more. 8. The toner manufacturing method according to claim 6, wherein the polyvalent metal having a valence of 2 or more is a metal selected from the group consisting of Cu, Al, and Fe. Any one of claims 1 to 8 , wherein the amount of the water-soluble metal salt added to the suspension is from 150 parts by mole to 850 parts by mole based on 100 parts by mole of the fatty acid metal salt. The method for manufacturing the toner described in . The method according to any one of claims 1 to 9, wherein the manufacturing method includes a step of adding resin particles in the alkali treatment step, and a step of fixing the resin particles to the surface of the polymer particles. Toner manufacturing method. The method for producing a toner according to claim 10, wherein the resin particles are particles containing a polymer A having a monovalent group a represented by the following formula (1).

(In formula (1), R ¹ represents a hydroxy group, a carboxy group, an alkyl group having 1 to 18 carbon atoms, or an alkoxy group having 1 to 18 carbon atoms, and R ² represents a hydrogen atom, a hydroxy group , represents an alkyl group having 1 to 18 carbon atoms, or an alkoxy group having 1 to 18 carbon atoms, g represents an integer of 1 to 3, and h represents an integer of 0 to 3. is 2 or 3, h R ¹ 's may be the same or different.)