JP2022094792A - Method for producing external additive particle, external additive particle and toner - Google Patents

Abstract

To provide an external additive particle capable of providing a toner possibly having an excellent fluidity, the fluidity unlikely to change even if continuous image outputs are executed, and a method for producing the same.SOLUTION: A method for producing an external additive particle containing a polymer includes: a radical polymerization process of conducting a radical polymerization reaction of a monomer raw material containing a chemical compound expressed by a formula (3) below, using a radical polymerization initiator having a carboxyl group, under a condition of 6.0≤pH≤8.0; and a condensation process of obtaining a particle containing a polymer, through conducting, after the radical polymerization process, a hydrolysis reaction and a polycondensation reaction of a hydrolyzable group X in the formula (3): R6mSiX4-m ...(3) (In the formula (3), X denotes a hydrolyzable group, m denotes an integer of 1 to 3, R6 each is independently an organic group having 1 to 20 carbon atoms, and at least one R6 is a radical-polymerizable group.).SELECTED DRAWING: None

Description

The present invention relates to external additive particles, a method for producing the same, and a toner.

In recent years, an image forming apparatus using an electrophotographic method is required to have higher speed and higher image quality. In response to these demands, toners with excellent fluidity and developability have been studied in order to have stress resistance that can withstand rubbing in a developing device for a long time and to obtain high image quality even in high-speed printing. ..

Patent Document 1 discloses a method for producing organic-inorganic composite particles having an organic polymer skeleton and a polysiloxane skeleton as an additive for toner. It is disclosed that the transfer characteristics and the like of the toner are improved by incorporating the toner additive into the toner.

Japanese Unexamined Patent Publication No. 9-197706

As a result of the examination by the present inventors on the toner to which the particles produced by the method described in Patent Document 1 are externally added, it was recognized that further improvement in the fluidity of the toner is necessary.

One aspect of the present invention is aimed at providing external additive particles and a method for producing the same, which can have excellent fluidity and give toner whose fluidity does not change easily even when continuous image output is performed. Is.

Further, another aspect of the present invention is aimed at providing a toner which can have excellent fluidity and whose fluidity does not easily change even when continuous image output is performed.

According to one aspect of the present invention, it is a method for producing external additive particles containing a polymer.
The manufacturing method is
A radical polymerization step of carrying out a radical polymerization reaction of a monomer raw material containing a compound represented by the following formula (3) using a radical polymerization initiator having a carboxy group under the condition of 6.0 ≤ pH ≤ 8.0. After the radical polymerization step, the hydrolyzable group X in the following formula (3) is subjected to a hydrolysis reaction and a polycondensation reaction to obtain particles containing a polymer.
A method for producing external additive particles containing the above is provided.

R ⁶ _m SiX _4-m ... (3)
(In formula (3), X is a hydrolyzable group, m is an integer of 1 to 3, R ⁶ is an independently organic group having 1 to 20 carbon atoms, and at least 1 of R ⁶ is used. One is a radically polymerizable group.)
Further, according to another aspect of the present invention, there is a method for producing external additive particles containing a polymer.
The manufacturing method is
Under the condition of 6.0 ≤ pH ≤ 8.0, radical polymerization of a monomer raw material containing at least one of a radically polymerizable carboxylic acid and a radically polymerizable carboxylic acid salt, and a compound represented by the following formula (3). Radical polymerization step to carry out the reaction,
After the radical polymerization step, the hydrolytic group X in the following formula (3) is subjected to a hydrolysis reaction and a polycondensation reaction to obtain particles containing a polymer.
A method for producing external additive particles containing the above is provided.

R ⁶ _m SiX _4-m ... (3)
(In formula (3), X is a hydrolyzable group, m is an integer of 1 to 3, R ⁶ is an independently organic group having 1 to 20 carbon atoms, and at least 1 of R ⁶ is used. One is a radically polymerizable group.)

According to one aspect of the present invention, it is possible to obtain external additive particles that can have excellent fluidity and give toner that can maintain excellent fluidity retention even when continuous image output is performed. can. Further, according to another aspect of the present invention, it is possible to obtain a toner that can maintain excellent flow retention even when continuous image output is performed.

Unless otherwise specified, the description of "○○ or more and XX or less" and "○○ to XX" indicating a numerical range means a numerical range including a lower limit and an upper limit which are end points. When numerical ranges are described step by step, the upper and lower limits of each numerical range can be arbitrarily combined.

<Background to the invention>
The present inventors consider the reason why the fluidity of the toner externally added with the particles produced by the production method according to Patent Document 1 needs to be further improved as follows.

It has been discovered that the toner externally supplemented with particles produced by the production method according to Patent Document 1 may not have sufficient fluidity. In the production method, since the vinyl group is polymerized after hydrolyzing and polycondensing the hydrolyzable group bonded to silicon, it is considered that particles having a polysiloxane skeleton as the main skeleton are formed. Since the main skeleton of the particles is an inorganic skeleton, the adhesive force to the toner particles may not be sufficient, and the particles are easily separated from the surface of the toner particles, which is one of the causes of the decrease in the fluidity of the toner. The present inventors are thinking.

Therefore, the present inventors examined particles whose main skeleton is a molecular chain of a vinyl polymer, which is obtained by a production method in which hydrolysis and polycondensation are performed after vinyl polymerization. The particles are obtained from toner particles. It became difficult to separate, and a certain improvement was seen in the fluidity of the toner. However, there is room for further improvement in the change over time in the flowability of the toner when continuous image output is performed, that is, the flowability of the toner.

As a result of diligent studies by the present inventors based on the above considerations, the toner externally added with the external additive particles produced by the production method having the above-mentioned constituent requirements can have excellent fluidity and is excellent. It has been found that it is easy to obtain a toner that can maintain flow. The mechanism for estimating the effect onset and the constituent requirements for each will be described in detail below.

<Guessing mechanism for expressing the effect of the present invention>
By radical polymerization using a monomer raw material containing the compound represented by the formula (3) and then hydrolysis and polycondensation, a polymer having a molecular chain of a vinyl-based polymer as a main skeleton can be obtained. Moreover, the polymer contains a structure in which the molecular chain is bonded via a siloxane bond.

Since the main skeleton of the polymer is a molecular chain of a vinyl-based polymer, the adhesive force to the toner particles tends to increase. Further, it is considered that the molecular chain of the vinyl-based polymer has a structure bonded via a siloxane bond, so that the mechanical strength of the external additive particles tends to increase and plastic deformation is less likely to occur.

As a result, it is considered that the external additive particles containing the polymer are hard to separate from the toner particles and plastic deformation is hard to occur, so that a toner having excellent fluidity can be easily obtained.

Further, in the method for producing external additive particles according to the present invention, it is considered that a carboxy group is contained in the surface region of the external additive particles produced by at least one of the following (i) and (ii).
(I) A radical polymerization initiator having a carboxy group is used in the radical polymerization step.
(Ii) At least one of a radically polymerizable carboxylic acid and a radically polymerizable carboxylic acid salt is used as a monomer raw material.

By containing the carboxy group in the surface region of the external additive particles, it becomes easy to strongly interact with the electrostatically interactable portion existing on the surface of the toner particles, and the external additive particles can be more easily interacted with from the surface of the toner particles. The present inventors speculate that it will be difficult to separate. As a result, it becomes easy to obtain a toner that can have excellent flow retention even when continuous image output is performed.

<Manufacturing method of external additive particles>
The method for producing external additive particles according to the present invention contains both a radically polymerizable group and a hydrolyzable group that forms a siloxane bond by hydrolysis and polycondensation, and is a compound represented by the following formula (3). A radical polymerization reaction is carried out using the above, and then a hydrolysis reaction and a polycondensation reaction are carried out.

R ⁶ _m SiX _4-m ... (3)
(In formula (3), X is a hydrolyzable group, m is an integer of 1 to 3, R ⁶ is an independently organic group having 1 to 20 carbon atoms, and at least 1 of R ⁶ is used. One is a radically polymerizable group.)
By carrying out a radical polymerization reaction under neutral conditions before hydrolysis and polycondensation, a polymer having a molecular chain of a vinyl-based polymer as a main skeleton can be obtained. Further, by performing hydrolysis and polycondensation after the molecular chain of the vinyl-based polymer is formed by the radical polymerization reaction, a polymer having a structure in which the molecular chain of the vinyl-based polymer is bonded via a siloxane bond can be obtained. can get. Further, it is considered that by carrying out the hydrolysis reaction and the polycondensation reaction later, the carboxy group, which easily interacts with water molecules, is likely to be contained in the surface region of the external additive particles.

Examples of the above-mentioned hydrolyzable group include a functional group which is converted into a hydroxy group after the hydrolysis of the above-mentioned compound, or a hydroxy group.

Further, the radically polymerizable group means a substituent having a radically reactive double bond in the structure. The R ⁶ in the above formula (3) is more preferably an organic group having 1 to 15 carbon atoms, and further preferably R ⁶ is an organic group having 1 to 10 carbon atoms.

Here, it is preferable to use a radical polymerization initiator having a carboxy group as the radical polymerization initiator because the carboxy group can be contained in the surface region of the external additive particles. The radical polymerization initiator is preferably an azo compound.

Preferable examples of the radical polymerization initiator having a carboxy group include a compound represented by the following formula (2). Examples of the compound used as the radical polymerization initiator represented by the following formula (2) include 2,2'-azobis [N- (2-carboxyethyl) -2-methylpropionamidine].

(In the formula ( ² ), R5 is an alkylene group having 1 to 12 carbon atoms.)
In addition to using the above-mentioned radical polymerization initiator, as a method for containing a carboxy group in the surface region of the external additive particles, at least one of a radically polymerizable carboxylic acid and a radically polymerizable carboxylic acid salt is contained in the monomer raw material. It is mentioned to make it.

Examples of the radically polymerizable carboxylate include the following. Sodium 4-vinylbenzoate, potassium 4-vinylbenzoate, lithium 4-vinylbenzoate, magnesium 4-vinylbenzoate, calcium 4-vinylbenzoate, ammonium 4-vinylbenzoate, sodium (meth) acrylate, ( Potassium acrylate, (meth) lithium acrylate, (meth) magnesium acrylate, (meth) calcium acrylate, (meth) ammonium acrylate, etc. These radically polymerizable carboxylates may be used alone or in combination of two or more.

Examples of the radically polymerizable carboxylic acid include 4-vinylbenzoic acid and (meth) acrylic acid. These may be used alone or in combination of two or more.

From the viewpoint of maintaining the flow of the toner, the total mass of the radically polymerizable carboxylic acid and the radically polymerizable carboxylic acid salt may be 0.4 to 7.0% by mass with respect to the total mass of the monomer raw materials. preferable. It is more preferably 0.6 to 5.0% by mass, and even more preferably 0.6 to 2.0% by mass.

<Radical polymerization reaction>
As a method of radical polymerization reaction, an emulsion polymerization method is preferable. The emulsification polymerization method is carried out by mixing a medium such as water, a monomer sparingly soluble in the medium, an emulsifier (surfactant) or an ionic comonomer, and adding a polymerization initiator soluble in the above medium to the mixture. It is legal. Further, the above emulsification polymerization method is preferably a soap-free emulsification polymerization method in which polymerization is carried out without using a surfactant. The present inventors consider that this is because the soap-free emulsification polymerization method does not leave the surfactant on the surface of the external additive particles, and it is easy to control the affinity between the toner particles and the external additive particles. ..

Examples of the hydrolyzable group in the above formula (3) include a monovalent group selected from a hydroxy group, a fluoro group, a chloro group, a bromo group, an iodo group, an alkoxy group and an acyloxy group. It is preferably a methoxy group, an ethoxy group, a propoxy group or an acetoxy group, and more preferably a methoxy group or an ethoxy group. Since these hydrolyzable groups are easily hydrolyzed by water and a subsequent polycondensation reaction is likely to occur, it is considered that the polysiloxane skeleton is likely to be contained in the external additive particles.

From the viewpoint of toner fluidity and fluidity retention, the compound represented by the above formula (3) is preferably 50 to 80% by mass with respect to the total mass of the monomer raw materials. More preferably, it is 60 to 75% by mass.

Specific examples of the compound represented by the above formula (3), that is, a monomer containing both a radically polymerizable group and a hydrolyzable group, include the following.

γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-acryloxypropyltrimethoxysilane, γ-acryloxypropyltriethoxysilane, γ-methacryloxypropyltriacetoxysilane, vinyltrimethoxysilane, Organotrialkoxysilane compounds such as vinyltriethoxysilane, vinyltriacetoxysilane, 1-hexenyltrimethoxysilane, 1-octenyltrimethoxysilane, organotriacetoxysilane, bis (γ-acryloxypropyl) dimethoxysilane, bis ( Diorgano such as γ-methacryloxypropyl) dimethoxysilane, γ-methacryloxypropylethyldimethoxysilane, γ-methacryloxypropylethyldiethoxysilane, γ-acryloxypropylethyldimethoxysilane, γ-acryloxypropylethyldiethoxysilane Dialkoxysilane compound, tris (γ-acryloxypropyl) methoxysilane, tris (γ-acryloxypropyl) ethoxysilane, tris (γ-methacryloxypropyl) methoxysilane, tris (γ-methacryloxypropyl) ethoxysilane, bis (Γ-Acryloxypropyl) Vinyl methoxysilane, bis (γ-methacryloxypropyl) vinylmethoxysilane, γ-acryloxypropyldiethylmethoxysilane, γ-acryloxypropyldiethylethoxysilane, γ-methacryloxypropyldiethylmethoxysilane, Triorganoalkoxysilane compounds such as γ-methacryloxypropyldiethylethoxysilane.

Of the above monomers, more preferably, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-acryloxypropyltrimethoxysilane, γ-acryloxypropyltriethoxysilane, γ-methacryloxypropyl. Triacetoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane.

The compound represented by the above formula (3) is preferably a compound represented by the following formula (1).

(In the formula (1), R ¹ is an alkylene group having 1 to 10 carbon atoms, and R ² , R ³ and R ⁴ are independently any of hydrogen, methyl group and ethyl group. , R'is a hydrogen or methyl group.)
<Radical polymerization initiator>
In addition to the above-mentioned radical polymerization initiator having a carboxy group, examples of the radical polymerization initiator that can be used include at least one compound selected from a persulfate, an azo compound, and a peroxide.

Examples of the persulfate include potassium persulfate, sodium persulfate, ammonium persulfate and the like. These may be used alone or in combination of two or more.

The amount of the radical polymerization initiator in the radical polymerization step is not particularly limited, but is preferably 0.1 to 10.0% by mass, preferably 0.3 to 5.% by mass, based on the total mass of the raw material monomers. It is more preferably 0% by mass. It is preferable that the radical polymerization initiator is within the above range because the radical polymerization can be sufficiently promoted and the calorific value in the reaction system is unlikely to become excessive.

<Conditions for radical polymerization reaction>
The temperature at the time of radical polymerization can be appropriately selected depending on the type and amount of the radical polymerization initiator used, and is preferably in the range of 30 to 100 ° C, more preferably in the range of 50 to 80 ° C.

The radical polymerization step is a step of performing radical polymerization under the condition of 6.0 ≦ pH ≦ 8.0. More preferably, 6.5 ≦ pH ≦ 7.5. When the pH of the reaction system is within the above range, it is considered that the hydrolysis of the hydrolyzable group and the polycondensation reaction are less likely to occur during the progress of the radical polymerization reaction. By performing hydrolysis and polycondensation reaction after radical polymerization, it is easy to control the ratio of polysiloxane skeleton in the external additive particles, and carboxy groups with higher polarity are likely to be contained in the surface region of the external additive particles. It is considered to be. Therefore, the radical polymerization reaction is preferably carried out in a buffer solution. The buffer solution is not particularly limited, and any buffer solution having a pH near neutral, such as a phosphate buffer solution or a MES buffer solution, may be used.

Further, in the radical polymerization, not only a monomer containing both a radically polymerizable group and a hydrolyzable group but also another monomer having a radically polymerizable group may be used.

Examples of other monomers include unsaturated carboxylic acids such as acrylic acid and methacrylic acid, acrylic acid esters, methacrylic acid esters, crotonic acid esters, itaconic acid esters, maleic acid esters, fumaric acid esters and the like. Unsaturated carboxylic acid esters, acrylamides, methacrylicamides, aromatic vinyl compounds such as styrene, α-styrene and divinylbenzene, vinyl esters such as vinyl acetate, vinyl compounds such as halogenated vinyl compounds such as vinyl chloride. Esters and the like can be mentioned. Further, a monomer such as divinylbenzene, trimethylolpropane trimethacrylate, or ethylene glycol dimethacrylate containing two or more radically polymerizable groups may be used. These may be used alone or in combination of two or more.

<Hydrolyzation reaction and polycondensation reaction>
The method of the above hydrolysis reaction and polycondensation reaction is not particularly limited, but a catalyst such as an acid or a base is added to the emulsion containing the particles obtained by radical polymerization, and hydrolysis and polycondensation are carried out as they are. It is preferable to obtain particles containing the polymer. That is, the condensation step is preferably a step in which the hydrolyzable group X in the formula (3) is subjected to a hydrolysis reaction and a polycondensation reaction after the radical polymerization step to obtain particles of the condensate. Further, the particles obtained by radical polymerization may be isolated from the emulsion by performing operations such as stirring, centrifugation, and concentration under reduced pressure, and then hydrolyzed and polycondensed by adding a catalyst.

In carrying out hydrolysis and polycondensation reaction after particle formation by radical polymerization reaction, acetic acid, hydrochloric acid, ammonia, urea, alkanolamine, tetraalkylammonium hydroxide, alkali metal hydroxide, alkaline earth metal hydroxide, etc. A catalyst may be used.

More preferable catalysts from the viewpoint of further promoting polycondensation include organic titanium compounds such as titanium tetraisopropoxide, titanium tetrabutoxide, diisopropoxy-bis (acetylacetonate) titanate, aluminum triisopropoxide, and aluminum trisec. -Organic aluminum compounds such as butoxide, aluminumtris acetylacetonate, aluminum isopropoxide-bisacetylacetonate, organic zirconium compounds such as zirconium tetrabutoxide, tetrakis (acetylacetonate) zirconium, dibutyltin diacetate, dibutyltin diethylhexa Examples thereof include organic tin compounds such as noate and dibutyltin dimaleate, and acidic phosphoric acid esters. These may be used alone or in combination of two or more. Among them, at least one selected from the group consisting of an organic tin compound and an acidic phosphoric acid ester is preferable.

Further, the solvent used in the production of the external additive particles may contain an organic solvent other than water or a catalyst. Specific examples of the organic solvent include methanol, ethanol, isopropanol, n-butanol, isobutanol, sec-butanol, t-butanol, pentanol, ethylene glycol, propylene glycol, alcohols such as 1,4-butanediol, and acetone. , Ketones such as methyl ethyl ketone, esters such as ethyl acetate, (cyclo) paraffins such as isooctane and cyclohexane, ethers such as dioxane and diethyl ether, aromatic hydrocarbons such as benzene and toluene. Two or more kinds may be mixed and used.

The hydrolysis reaction and polycondensation reaction are carried out, for example, by appropriately adding a catalyst to the emulsion prepared by the radical polymerization reaction and stirring at 0 to 100 ° C., preferably 0 to 70 ° C. for 3 to 24 hours. Can be done.

<Surface treatment with amine compounds>
From the viewpoint of density stability of the output image, it is preferable to perform surface treatment of particles containing the above polymer with an amine compound. It has been found that by performing the surface treatment, the image density is less likely to vary in the image output in a low humidity environment. The reason for this is not clear, but the present inventors speculate as follows.

In the process of acquiring electric charge of the toner by triboelectric charging, negative electric charge is likely to be accumulated in the toner due to the influence of negatively charged functional groups such as carboxy groups existing on the surface of the external additive particles and the surface of the toner particles. It is considered that by performing surface treatment with an amine compound, the amine portion derived from the amine compound tends to have a positive charge by receiving hydrogen ions, and excessive accumulation of negative charges is less likely to occur in the toner as a whole. As a result, even in a low-humidity environment where the toner is likely to be overcharged, it is considered that the toner is less likely to be overcharged and the toner whose image density is less likely to vary can be easily obtained.

The amine compound used in the surface treatment and the particles containing the polymer may or may not be chemically bonded.

Examples of the above amine compounds include aminosilanes such as 3-aminopropyltrimethoxysilane, 3- (2-aminoethylamino) propyltrimethoxysilane, 3- (2-aminoethylamino) propyldimethoxydimethylsilane, and polyallylamine. Examples thereof include amino group-containing polymers and polyethyleneimine.

The content of the amine portion contained in the surface region of the external additive particles by the surface treatment using the amine compound can be confirmed by performing X-ray photoelectron spectroscopy on the surface of the external additive particles. can. In addition, when X-ray photoelectron spectroscopy was performed on the surface of the external additive particles that had undergone the surface treatment, the nitrogen atom was relative to the total number of carbon atoms, nitrogen atoms, oxygen atoms, and silicon atoms. The ratio of the number of atoms of is preferably 1.0% or more and 2.5% or less. It was found that when the ratio of the number of nitrogen atoms was within the above range, the image density was less likely to vary in a low humidity environment.

In addition, from the viewpoint of toner chargeability, in order to treat the hydroxyl groups remaining on the surface of the external additive particles and to adjust the amount of negative charge, other surface treatment agents are used to surface-treat the external additive particles. It is preferable to do it. Examples of the other surface treatment agent include silicon compounds such as organoalkoxysilane and hexamethyldisilazane, titanium compounds such as tetrabutyl titanate, and hydrolyzed / condensed products thereof.

The surface treatment using the other surface treatment agent may be performed at the same time as the surface treatment using the above amine compound, or may be performed after the surface treatment using the above amine compound.

The method for performing the above surface treatment is not particularly limited as long as the surface of the particles can be covered with the above surface treatment agent. For example, the particles are placed in a suitable container, then the surface treatment agent is added, and then the particles are mixed at a temperature of about room temperature (25 ° C ± 5 ° C) to 100 ° C for 3 to 24 hours with stirring and brought into contact with each other. Can be done. In this case, the surface treatment can be further uniformly performed by dissolving the surface treatment agent in a solvent such as methanol and mixing and contacting the surface treatment agent while gradually dropping the surface treatment agent. The amount of the surface treatment agent present on the surface of the particles can be adjusted by appropriately selecting the type of the surface treatment agent, the time of the surface treatment, the particle size of the external additive particles, and the like. By cleaning the object to be surface-treated in this way with, for example, alcohol, if necessary, it is possible to obtain external additive particles from which unnecessary substances have been removed.

<Post-processing>
The particles obtained by radical polymerization, hydrolysis / polycondensation, and surface treatment as described above were isolated from the slurry by methods such as stirring, centrifugation, concentration under reduced pressure, spray drying, and instantaneous vacuum drying. After that, it is preferable to carry out a drying treatment at 30 to 100 ° C. It is more preferable to carry out the drying treatment at 30 to 80 ° C, more preferably 50 to 70 ° C. By performing the drying treatment, it is easy to obtain external additive particles having appropriate charging characteristics and appropriate mechanical strength.

<Physical characteristics of external additive particles>
<Ratio of the number of silicon atoms to the total number of carbon, oxygen, and silicon atoms>
The ratio of the number of silicon atoms to the total number of carbon atoms, oxygen atoms, and silicon atoms in the external agent particles is preferably 4.0% or more and 25.0% or less.

The total number of atoms of carbon atom, oxygen atom, and silicon atom is an index of how many polymers have a structure in which the molecular chains of the above vinyl-based polymer are bonded via a siloxane bond. The inventors are thinking. Further, the present inventors consider that the ratio of the number of atoms of silicon atom to the total number of atoms described above is an index of how many siloxane bonds are present.

When the above ratio is 4.0% or more, it is considered that siloxane bonds are sufficiently formed in the polymer and plastic deformation of the external additive particles is unlikely to occur, so that a toner having excellent fluidity can be obtained. Easy to get rid of. Further, when the above ratio is 25.0% or less, it is considered that the molecular chain of the vinyl-based polymer as the main skeleton is sufficiently contained in the polymer, and the external additive particles are difficult to separate from the toner particles. Therefore, it is easy to obtain a toner having excellent flow retention. Therefore, it is 25.0% or less, preferably 20.0% or less, more preferably 15.0% or less, and further preferably 10.0% or less. That is, it is more preferable that the above ratio is 4.0% or more and 10.0% or less.

Further, since it is easy to obtain a toner having excellent flow retention, the ratio of the number of carbon atoms in the external additive particles is 6.5 or more with respect to the number of silicon atoms in the external additive particles. Is preferable. It is more preferably 7.5 or more, and even more preferably 13.5 or more. The upper limit is not particularly limited, but is preferably 20.0 or less from the viewpoint of toner fluidity. More preferably, it is 17.0 or less.

The above-mentioned ratio of the number of atoms adjusts the type and amount of the monomer unit containing a silicon atom and the type and amount of the monomer unit not containing a silicon atom in the production of the polymer constituting the external additive particles. By doing so, it can be controlled.

<D50 of external additive particles>
In order to obtain an appropriate volume average particle size as the external additive particles, it is preferable that the D50 is 50 nm or more and 200 nm or less when the 50% particle size based on the volume distribution of the external additive particles is D50.

<Toner>
The external additive particles according to the present invention are preferably contained on the surface of the toner particles. That is, as one of the aspects of the present invention, the toner contains toner particles and an external additive on the surface of the toner particles, and the external additive is an external additive produced by the production method according to the present invention. It is preferably toner which is a particle.

Further, the toner particles preferably contain a binder resin. Examples of the binder resin include polyester-based resin, vinyl-based resin, epoxy resin, and polyurethane resin.

From the viewpoint of storage stability, the binder resin preferably has a glass transition point (Tg) of 45 to 70 ° C.

<Manufacturing method of toner particles>
The method for producing the toner particles according to the present invention is not particularly limited, and for example, a pulverization method, an emulsion polymerization method, a suspension polymerization method, a dissolution suspension method, or the like can be used.

The crushing method will be described. In the pulverization method, first, the binder resin, the colorant, the wax, the charge control agent and the like constituting the toner particles are sufficiently mixed by a mixer such as a Henschel mixer or a ball mill. Next, the obtained mixture is melt-kneaded using a heat kneader such as a twin-screw kneading extruder, a heating roll, a kneader, and an extruder, cooled and solidified, and then pulverized and classified. As a result, the toner particles according to the present invention can be obtained.

Examples of the kneading machine include the following. KRC kneader (manufactured by Kurimoto Iron Works); Busco kneader (manufactured by Buss); TEM type extruder (manufactured by Toshiba Machine Co., Ltd.); TEX twin-screw kneader (manufactured by Japan Steel Works); PCM kneader (manufactured by Ikekai) Iron Works); Three roll mill, mixing roll mill, kneader (Inoue Mfg. Co., Ltd.); Kneedex (Mitsui Mine Co., Ltd.); MS type pressurized kneader, Kneader Luder (Nippon Spindle Co., Ltd.); Banbury mixer (Kobe Steel) Made by Tokorosha).

Examples of the crusher include the following. Counter jet mill, micron jet, innomizer (manufactured by Hosokawa Micron); IDS type mill, PJM jet crusher (manufactured by Nippon Pneumatic Industries); cross jet mill (manufactured by Kurimoto Iron Works); Ulmax (manufactured by Nippon Soda Engineering Co., Ltd.) ); SK Jet O Mill (manufactured by Seishin Corporation); Cryptron (manufactured by Kawasaki Heavy Industries); Turbo Mill (manufactured by Turbo E Co., Ltd.); Super Rotor (manufactured by Nisshin Engineering Co., Ltd.).

Examples of the classifier include the following. Classil, Micron Classifier, Spedic Classifier (manufactured by Seishin Corporation); Turbo Classifier (manufactured by Nisshin Engineering Co., Ltd.); Micron Separator, Turboplex (ATP), TSP Separator (manufactured by Hosokawa Micron); Elbow Jet (Japan) Iron Mining Co., Ltd.), Dispersion Separator (manufactured by Nippon Pneumatic Co., Ltd.); YM Microcut (manufactured by Yasukawa Shoji Co., Ltd.).

The suspension polymerization method will be described. In the suspension polymerization method, first, a polymerizable monomer capable of producing a binder resin and various additives as necessary are mixed, and the material is dissolved or dispersed using a disperser. Prepare a weight composition. Examples of various additives include colorants, waxes, charge control agents, polymerization initiators, chain transfer agents and the like. Dispersers include homogenizers, ball mills, colloid mills, or ultrasonic dispersers. Next, the polymerizable monomer composition is put into an aqueous medium containing poorly water-soluble inorganic fine particles, and the polymerizable monomer composition is composed using a high-speed disperser such as a high-speed stirrer or an ultrasonic disperser. Prepare droplets of material (granulation process). Then, the polymerizable monomer in the droplet is polymerized to obtain toner particles (polymerization step). The polymerization initiator may be mixed when preparing the polymerizable monomer composition, or may be mixed in the polymerizable monomer composition immediately before forming droplets in the aqueous medium. Further, it can be added in a state of being dissolved in a polymerizable monomer or another solvent, if necessary, during the granulation of the droplets or after the completion of the granulation, that is, immediately before the start of the polymerization reaction. After polymerizing the polymerizable monomer to obtain a binder resin, it is preferable to perform a solvent removal treatment as necessary to obtain a dispersion liquid of toner particles.

<Method of externalizing the externalizing agent particles to the toner particles>
The toner according to the present invention can be obtained by mixing toner particles and external additive particles with a mixer such as a Henschel mixer.

Examples of the mixer include the following. Henschel Mixer (Mitsui Mining Co., Ltd.); Super Mixer (Kawata Co., Ltd.); Ribocorn (Okawara Seisakusho Co., Ltd.); Nowter Mixer, Turbulizer, Cyclomix (Hosokawa Micron Co., Ltd.); Spiral Pin Mixer (Pacific Kiko Co., Ltd.) Ladyge mixer (manufactured by Matsubo).

Further, it is preferable that the toner particles contain the above-mentioned external additive particles on the surface thereof and also contain other external additives. Examples of other external additives include the following.

Fluorine resin powder such as vinylidene fluoride fine powder, polytetrafluoroethylene fine powder; fine powder silica such as wet manufacturing silica, dry manufacturing silica, fine powder titanium oxide, fine powder alumina, silane compound, titanium coupling agent , Surface-treated silica with silicone oil; oxides such as zinc oxide and tin oxide; compound oxides such as strontium titanate, barium titanate, calcium titanate, strontium zirconate and calcium zirconate; calcium carbonate and , Carbonate compounds such as magnesium carbonate, etc.

<Various toner additives>
If necessary, the toner may contain one or more additives selected from colorants, waxes, magnetic substances, charge control agents and the like. Various additives used in the toner will be specifically described.

<Magnetic material>
The toner may contain magnetic particles and may be used as a magnetic toner. In this case, the magnetic particles may have a role as a colorant.

Examples of the magnetic particles contained in the magnetic toner include the following.

Metals such as iron oxide, iron, cobalt, nickel such as magnetite, hematite, ferrite or these metals and aluminum, cobalt, copper, lead, magnesium, tin, zinc, antimony, bismuth, calcium, manganese, titanium, tungsten , Metal alloys such as vanadium and mixtures thereof.

The average particle size of the magnetic particles is preferably 2 μm or less. More preferably, it is 0.05 μm or more and 0.5 μm or less. The content ratio of the magnetic particles is preferably 20 parts by mass or more and 200 parts by mass or less with respect to 100 parts by mass of the binder resin, and more preferably 40 parts by mass or more with respect to 100 parts by mass of the binder resin. It is 150 parts by mass or less.

<Colorant>
Examples of the colorant include the following.

As the black colorant, for example, carbon black, grafted carbon, or a yellow / magenta / cyan colorant shown below is used to adjust the color to black.

As a yellow colorant, a compound typified by a condensed azo compound, an isoindolinone compound, an anthraquinone compound, an azo metal complex, a methine compound, and an allylamide compound.

Examples of the magenta colorant include condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, perylene compounds and the like. Examples of the cyan colorant include copper phthalocyanine compounds and their derivatives, anthraquinone compounds, and basic dye lake compounds.

The colorant can be used alone or mixed, and further in the form of a solid solution. The colorant is selected from the viewpoints of hue angle, saturation, lightness, weather resistance, OHP transparency, and dispersibility in toner.

The content ratio of the colorant is preferably 1 part by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the binder resin.

<Wax>
Examples of the wax include the following.

Low molecular weight polyethylene, low molecular weight polypropylene, polyolefin copolymers, polyolefin waxes, microcrystallin waxes, paraffin waxes, aliphatic hydrocarbon waxes such as Fishertropsh wax, oxides of aliphatic hydrocarbon waxes such as polyethylene oxide wax, Block copolymers of aliphatic hydrocarbon waxes and their oxides.

Ester waxes containing fatty acid esters such as carnauba wax as the main component; deoxidized fatty acid esters such as carnauba wax partially or wholly deoxidized.

<Charge control agent>
The charge control agent is not particularly limited, but is preferably an organometallic complex or a chelate compound. For example, a monoazo metal complex; an acetylacetone metal complex; a metal complex or a metal salt of an aromatic hydroxycarboxylic acid or an aromatic dicarboxylic acid can be mentioned.

Specific examples that can be used include Spiron Black TRH, T-77, T-95 (Hodogaya Chemical Co., Ltd.), BONTRON (registered trademark) S-34, S-44, S-54, E-84, E-. 88, E-89 (Orient Chemical Co., Ltd.) can be mentioned. Further, the charge control resin can also be used in combination with the above-mentioned charge control agent.

<Developer>
Toner can also be used as a one-component developer, but it is used as a two-component developer by mixing with a magnetic carrier in order to further improve dot reproducibility and to supply a stable image for a long period of time. You may.

As the magnetic carrier, for example, iron having an oxidized surface, iron having an unoxidized surface, nickel, cobalt, manganese, chromium, metals such as rare earths, and alloys or oxides thereof are preferably used.

Further, it is preferable that the surface of the magnetic carrier contains or is coated with a styrene resin, an acrylic resin, a silicone resin, a fluorine resin, or polyester.

<Various measurement methods, etc.>
Hereinafter, various measurement methods and the like will be described.

<Method of measuring the ratio of the number of silicon atoms to the total number of carbon atoms, oxygen atoms, and silicon atoms present in the external agent particles, and the abundance ratio of carbon atoms to silicon atoms>
-Carbon atoms and oxygen atoms The concentrations (atomic%) of carbon atoms and oxygen atoms present in the external additive particles are calculated using elemental analysis by combustion. The device for elemental analysis is shown below.
Equipment used: PerkinElmer 2400II fully automatic elemental analyzer-Silicon atom The concentration (atomic%) of silicon atoms present in the particles is determined by elemental analysis by inductively coupled plasma emission spectrometry (ICP-AES) by alkaline melting. Measure using. The ICP-AES device is shown below.
Equipment used: ICPS-8100 manufactured by Shimadzu Corporation
By converting the obtained composition ratio to mol%, the converted value is used to determine the number of silicon atoms with respect to the total number of carbon atoms, oxygen atoms, and silicon atoms in the additive particles. Calculate the ratio. Similarly, the ratio of the number of carbon atoms to the number of silicon atoms in the external additive particles is calculated.

<Method of measuring the ratio of the number of nitrogen atoms to the total number of carbon atoms, nitrogen atoms, oxygen atoms, and silicon atoms in the surface region of the external additive particles>
The ratio of the number of nitrogen atoms present in the surface region of the external additive particles is measured by X-ray photoelectron spectroscopy. The equipment and measurement conditions are shown below.
-Device used: ULVAC-PHI PHI Quantera SXM
・ Measurement conditions of X-ray photoelectron spectroscope:
X-ray source Al Kα (1486.6 eV) 200 μmφ
PassEnergy: 140eV
Charge neutralization: Combined use of electron neutralization gun and Ar ion neutralization gun Swep number: C 20 times, N 100 times, O 20 times, Si 20 times From the peak intensity of each element measured, provided by ULVAC-PHI. Using the relative sensitivity factor, the atomic concentrations of carbon atoms, nitrogen atoms, oxygen atoms, and silicon atoms present in the surface region of the external additive particles (all in atomic%) were calculated. From this result, the ratio of the number of nitrogen atoms to the total number of carbon atoms, nitrogen atoms, oxygen atoms, and silicon atoms on the surface of the external additive particles is calculated.

<Measurement method of 50% particle size (D50) based on volume distribution of fine particle sample>
A dynamic light scattering type particle size distribution meter Nanotrack UPA-EX150 (manufactured by Nikkiso) is used to measure the 50% particle size (D50) based on the volume distribution of the fine particle sample. Specifically, the range is set to 0.001 μm to 10 μm, and the measurement is performed according to the following procedure.

In order to prevent the agglomeration of the measurement sample, the dispersion liquid in which the measurement sample is dispersed is put into an aqueous solution containing Family Fresh (manufactured by Kao Corporation) and stirred. After stirring, the measurement sample is injected into the above device, and the measurement is performed twice to obtain the average value.

As the measurement conditions, the measurement time is 30 seconds, the refractive index of the sample particles is 1.49, the dispersion medium is water, and the refractive index of the dispersion medium is 1.33.

The volume particle size distribution of the measurement sample is measured, and the particle size at which the cumulative volume from the small particle size side in the cumulative volume distribution is 50% from the measurement result is defined as the 50% particle size (D50) based on the volume distribution of each fine particle. ..

Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited to these Examples. Unless otherwise specified, "parts" and "%" mean "parts by mass" and "% by mass", respectively. Further, each measurement result in the examples is a result measured by the measurement method described above.

<Manufacturing example of external additive 1>
The following materials were put into a glass reactor equipped with a thermometer, a reflux condenser, a nitrogen gas introduction tube, and a stirrer.
・ Phosphoric acid buffer (pH = 7.0, prepared using sodium dihydrogen phosphate dihydrate (manufactured by Kishida Chemical Co., Ltd.) and disodium hydrogen phosphate dusohydrate (manufactured by Kishida Chemical Co., Ltd.)) 200 Part ・ 0.1 mol / l sodium hydroxide aqueous solution (manufactured by Kishida Chemical Co., Ltd.) 1.2 part ・ Emulsifier: 4-vinyl benzoate sodium (manufactured by Tokyo Kasei Kogyo Co., Ltd.) 0.18 part ・ Radical polymerizable group and hydrolyzable Radical-containing monomer: 3- (trimethoxysilyl) propyl methacrylate (manufactured by Tokyo Kasei Kogyo Co., Ltd.) 11.0 parts ・ Non-hydrolytable monomer: styrene (manufactured by Tokyo Kasei Kogyo Co., Ltd.) 4.7 parts Next, nitrogen gas After warming to 65-70 ° C. with aeration and stirring for 30 minutes, as an initiator, 2,2'-azobis [N- (2-carboxyethyl) -2-methylpropionamidine] (VA-057, (Fujifilm Wako Junyaku Co., Ltd.) 1.5 parts was added, and stirring was continued for 6 hours to obtain an emulsion of particles. As an ammonia treatment, 28% by mass ammonia water (manufactured by Kishida Chemical Co., Ltd.) was added to the obtained particle emulsion to adjust the pH of the emulsion to 11.0, and then the mixture was stirred at a temperature of 50 ° C. for 3 hours. The hydrolyzable groups contained in the particles were hydrolyzed and polycondensed. Then, extrafiltration was performed to remove excess solute, and concentration / filtration was repeated 5 times in total. After that, 0.13 part of 3-aminopropyltrimethoxysilane (manufactured by Tokyo Chemical Industry Co., Ltd.) was used as the nitrogen atom source, and 1,1,1,3,3,3-hexamethyldisilazane (Kishida Chemical Co., Ltd.) was used as the hydrophobic treatment agent. 27.0 parts was added, and the mixture was stirred at a temperature of 50 ° C. for 24 hours. Then, it was dried by spray drying to obtain an external preparation 1 having a volume distribution-based 50% particle size (hereinafter, also referred to as D50) of 130 nm. Table 2 shows the physical characteristics of the external additive 1.

<Manufacturing examples of external additives 2 to 19>
The same operations as in the production example of the external preparation 1 were carried out except that the materials used were changed as shown in Table 1, to obtain external preparations 2 to 19. Table 2 shows the physical characteristics of the external additives 2 to 19.

<Production example of external additive 20>
At room temperature, a solution containing the following materials is added to a solution in which 46.7 parts of 28% by mass ammonia water and 2114 parts of deionized water are mixed, and the mixture is stirred for 2 hours to form 3- (tri) methacrylate. Hydrolysis and polycondensation of methoxysilyl) propyl were performed.
・ 22.1 parts of 3- (trimethoxysilyl) propyl methacrylate ・ 73.7 parts of methanol (manufactured by Kishida Chemical Co., Ltd.) ・ Initiator: 2,2'-azobis (2,4-dimethylvaleronitrile) (V-65) , Fujifilm Wako Junyaku Co., Ltd.) 0.12 parts Next, radical polymerization was carried out by heating to 70 to 75 ° C. while aerating nitrogen gas and stirring for 2 hours. Then, extrafiltration was performed to remove excess solute, and concentration / filtration was repeated 5 times in total. After that, 0.22 parts of 3-aminopropyltrimethoxysilane (manufactured by Tokyo Chemical Industry Co., Ltd.) and 1,1,1,3,3,3-hexamethyldisilazane (manufactured by Kishida Chemical Co., Ltd.) 27 as a hydrophobic treatment agent. .0 parts were added and the mixture was stirred at a temperature of 50 ° C. for 24 hours. Then, it was dried by spray drying to obtain an external additive 20. Table 2 shows the physical characteristics of the external additive 20.

<Manufacturing example of external additive 21>
The following materials were put into a glass reactor equipped with a thermometer, a reflux condenser, a nitrogen gas introduction tube, and a stirrer.
・ 200 parts of deionized water ・ 0.1 mol / l sodium hydroxide aqueous solution (manufactured by Kishida Chemical Co., Ltd.) 1.2 parts ・ Emulsifier: Sodium 4-vinylbenzoate (manufactured by Tokyo Kasei Kogyo Co., Ltd.) 0.18 parts ・ Non-hydrolyzed Sexual monomer: Butyl methacrylate (manufactured by Tokyo Kasei Kogyo Co., Ltd.) 6.3 parts, and 4.7 parts of styrene Next, heat to 65-70 ° C while aerating nitrogen gas, stir for 30 minutes, and then the initiator. Add 1.5 parts of 2,2'-azobis [N- (2-carboxyethyl) -2-methylpropionamidine] (VA-057, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) and continue stirring for 6 hours. An emulsion of particles was obtained. Extrafiltration was performed to remove excess solute in the obtained emulsion, and concentration / filtration was repeated 5 times in total. After that, 0.13 part of 3-aminopropyltrimethoxysilane (manufactured by Tokyo Chemical Industry Co., Ltd.) was used as the nitrogen atom source, and 1,1,1,3,3,3-hexamethyldisilazane (Kishida Chemical Co., Ltd.) was used as the hydrophobic treatment agent. 27.0 parts was added, and the mixture was stirred at a temperature of 50 ° C. for 24 hours. Then, it was dried by spray drying to obtain an external additive 21. Table 2 shows the physical characteristics of the external additive 21.

The abbreviations in Table 1 are as follows.
MA-TMSP: 3- (trimethoxysilyl) propyl methacrylate MA-TESP: 3- (triethoxysilyl) propyl methacrylate AA-TMSP: 3- (trimethoxysilyl) acrylate propyl VTMS: vinyl trimethoxysilane MA- CDMSP: 3- (Chlorodimethylsilyl) propyl methacrylate St: styrene MAB: Butyl butyl Na (4-VBA): 4-Sodium vinyl benzoate NaMA: Sodium methacrylate NaPSS: Sodium p-styrene sulfonate VA-057: 2,2'-Azobis [N- (2-carboxyethyl) -2-methylpropionamidine]
KPS: Potassium persulfate V-65: 2,2'-azobis (2,4-dimethylvaleronitrile)
AP-TMS: 3-Aminopropyltrimethoxysilane (aminosilane having an amino group)
DMAP-TMS: [3- (N, N-dimethylamino) propyl] trimethoxysilane (aminosilane having a dialkylamino group)
IP-TMS: (3-Isocyanatopropyl) Trimethoxysilane (silane with isocyanate structure)
PAA-03E: Polyallylamine (weight average molecular weight: 3000)

In Table 2, Si / (C + O + Si) is the ratio of the number of silicon atoms to the total number of carbon atoms, oxygen atoms, and silicon atoms in the external agent particles, and C / Si is the external agent. It is the ratio of the number of carbon atoms to the number of silicon atoms in the particle. Further, N / (C + N + O + Si) is the ratio of the number of nitrogen atoms to the total number of carbon atoms, nitrogen atoms, oxygen atoms, and silicon atoms in the surface region of the external additive particles.

<Manufacturing example of toner particles 1>
After pre-mixing the following materials with a Henschel mixer, the temperature is set so that the melt temperature at the discharge port becomes 150 ° C. using a twin-screw extruder (trade name: PCM-30, manufactured by Ikekai Iron Works Co., Ltd.). Then, the mixture was melt-kneaded to obtain a kneaded product.
-Amorphous polyester (propylene oxide adduct of bisphenol A / terephthalic acid = 50/50, number average molecular weight: 3000, acid value: 12) 100 parts-Magnetic iron oxide particles 75 parts-Fishertro push wax (manufactured by Sazole) C105, melting point: 105 ° C) 2 parts, charge control agent (manufactured by Hodoya Chemical Co., Ltd., T-77) 2 parts The obtained kneaded material is cooled, roughly crushed with a hammer mill, and then crushed (trade name: turbo mill). It was finely pulverized using T250 (manufactured by Turbo Industries, Ltd.) to obtain a finely pulverized powder. The obtained finely pulverized powder was classified using a multi-division classifier utilizing the Coanda effect to obtain toner particles 1 having a weight average particle size of 7.2 μm.

<Manufacturing example of toner 1>
The external addition of the external additive to the toner particles 1 was performed by a dry method. To a Henschel mixer, 100 parts of toner particles, 1 part of 3 parts of external additive 1 and 1.5 parts of fumed silica (BET specific surface area: 200 m ² / g) were added and mixed. Then, it was sieved with a mesh having an opening of 150 μm to obtain a toner 1 having the external additive 1 externally added to the toner particles 1.

<Manufacturing example of toners 2 to 21>
In the production example of the toner 1, the toners 2 to 21 were obtained in the same manner as in the production example of the toner 1, except that the external additives 1 were changed to the external additives 2 to 21, respectively.

<Example 1>
The following evaluation was carried out using toner 1.

<Evaluation of toner fluidity>
Toner fluidity was measured by the following method.

First, using a powder tester (PT-X, manufactured by Hosokawa Micron), a sieve (plain weave wire mesh, standard JIS Z8801-1) with a mesh size of 150 μm, 100 μm, and 45 μm is vibrated under the condition of strength 4.0, and 3 g of toner is used. 1 was sieved with these sieves for 10 seconds. Then, when the remaining amount of toner on the sieve having an opening of 150 μm is A, the remaining amount of toner on the sieve having an opening of 100 μm is B, and the remaining amount of toner on the sieve having an opening of 45 μm is C, it is represented by the following formula. The fluidity of the toner was evaluated using the fluidity index (%). The evaluation results are shown in Table 3. When the liquidity index is 30% or less, it is judged that the effect of the present invention is obtained.

Liquidity index (%) = [(A + 0.6 × B + 0.2 × C) / mass of measured sample] × 100
<Evaluation of toner flow retention>
The evaluation of the flow sustainability of the toner was carried out after the above evaluation was performed.

HP LaserJet Enterprise M609dn (manufactured by HP) was used as an image forming apparatus, toner 1 was put into a cartridge, and 5000 images were output under the following conditions.
-Paper: GFC-081 (81.0 g / m ² ) (Canon Marketing Japan Inc.)
-Amount of toner on paper: 0.35 mg / cm ²
-Process speed: 377 mm / sec After that, the residual toner was taken out into the cartridge, the above-mentioned fluidity index was calculated for the residual toner, and the value was used as the endurance fluidity index. The volatility expressed by the following formula was calculated using the fluidity index obtained in the above evaluation of toner fluidity as the fluidity index before durability, and the value was used to evaluate the toner fluidity sustainability. ..

Volatility (%) = (Liquidity index after endurance-Liquidity index before endurance) / Liquidity index before endurance x 100
When the volatility was 100% or less, it was judged that the effect of the present invention was obtained.

<Evaluation of crushing of external additive particles and desorption from toner particles>
The evaluation of the crushing of the external additive particles and the desorption from the toner particles was performed after the above-mentioned evaluation of the flow retention of the toner was performed.

After outputting the above 5000 images, the toner 1 remaining in the cartridge is taken out, and the surface of the taken out toner 1 is observed with a scanning electron microscope (S-4800, manufactured by Hitachi High-Technology Co., Ltd.) and photographed by SEM. I got a statue. In the obtained image, when crushed deposits are observed on the surface of the toner, it is considered to be crushed, and when the recesses from which the external additive particles are desorbed are observed on the surface of the toner, there is desorption. , And said.

<Evaluation of image density stability>
Using the image forming apparatus used in the evaluation of the flow retention of the toner, the toner 1 was put into the cartridge, and 10,000 images were output under the same conditions as set in the evaluation of the flow retention of the toner.

While 10000 sheets were continuously output, calibration was not performed and the set conditions were not changed. The reflection density of all the output images was measured, and the image density stability was evaluated by the value of their standard deviations. When the standard deviation was less than 0.100, it was judged that the effect of the present invention was obtained. An X-Rite color reflection densitometer (500 series: manufactured by X-Rite) was used for measuring the reflection density of the image.

<Examples 2 to 19, Comparative Examples 1 and 2>
The same evaluation as in Example 1 was carried out using toners 2 to 21. The evaluation results are shown in Table 3.

Claims (13)

A method for producing external additive particles containing a polymer.
The manufacturing method is
A radical polymerization step of carrying out a radical polymerization reaction of a monomer raw material containing a compound represented by the following formula (3) using a radical polymerization initiator having a carboxy group under the condition of 6.0 ≤ pH ≤ 8.0. After the radical polymerization step, the hydrolyzable group X in the following formula (3) is subjected to a hydrolysis reaction and a polycondensation reaction to obtain particles containing a polymer.
A method for producing external additive particles including.
R ⁶ _m SiX _4-m ... (3)
(In formula (3), X is a hydrolyzable group, m is an integer of 1 to 3, R ⁶ is an independently organic group having 1 to 20 carbon atoms, and at least 1 of R ⁶ is used. One is a radically polymerizable group.) The method for producing external additive particles according to claim 1, wherein the radical polymerization initiator is a compound represented by the following formula (2).

(In the formula ( ² ), R5 is an alkylene group having 1 to 12 carbon atoms.) A method for producing external additive particles containing a polymer.
The manufacturing method is
Under the condition of 6.0 ≤ pH ≤ 8.0, radical polymerization of a monomer raw material containing at least one of a radically polymerizable carboxylic acid and a radically polymerizable carboxylic acid salt, and a compound represented by the following formula (3). Radical polymerization step to carry out the reaction,
After the radical polymerization step, the hydrolytic group X in the following formula (3) is subjected to a hydrolysis reaction and a polycondensation reaction to obtain particles containing a polymer.
A method for producing external additive particles including.
R ⁶ _m SiX _4-m ... (3)
(In formula (3), X is a hydrolyzable group, m is an integer of 1 to 3, R ⁶ is an independently organic group having 1 to 20 carbon atoms, and at least 1 of R ⁶ is used. One is a radically polymerizable group.) The method for producing external additive particles according to any one of claims 1 to 3, wherein the hydrolyzable group X in the formula (3) is an alkoxy group. The method for producing external additive particles according to any one of claims 1 to 4, wherein the compound represented by the formula (3) is a compound represented by the following formula (1).

(In the formula (1), R ¹ is an alkylene group having 1 to 10 carbon atoms, and R ² , R ³ and R ⁴ are independently any of hydrogen, methyl group and ethyl group. , R'is a hydrogen or methyl group.) The ratio of the number of silicon atoms to the total number of carbon atoms, oxygen atoms, and silicon atoms in the external agent particles is 4.0% or more and 25.0% or less.
The method for producing external additive particles according to any one of claims 1 to 5. 13. How to make external additive particles. The method for producing external additive particles according to any one of claims 1 to 7, further comprising a step of surface-treating the particles containing the polymer with an amine compound. The method for producing external additive particles according to claim 8, wherein the amine compound is aminosilane. When X-ray photoelectron spectroscopy is performed on the surface of the external additive particles,
The ratio of the number of nitrogen atoms to the total number of carbon atoms, nitrogen atoms, oxygen atoms, and silicon atoms is 1.0% or more and 2.5% or less.
The method for producing external additive particles according to any one of claims 1 to 9. When the 50% particle size based on the volume distribution of the external additive particles is D50,
The method for producing external additive particles according to any one of claims 1 to 10, wherein D50 is 50 nm or more and 200 nm or less. External additive particles produced by the production method according to any one of claims 1 to 11. A toner containing toner particles and an external additive on the surface of the toner particles.
The toner in which the external additive is the external additive particles according to claim 12.