JP2014085613A - Toner for electrostatic charge image development, electrostatic charge image developer, toner cartridge, developer cartridge, process cartridge, image forming method, and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a toner for electrostatic charge image development that suppresses a reduction in transfer efficiency even after printing of a large number of sheets.SOLUTION: A toner for electrostatic charge image development contains toner base particles, and an external additive externally added to the toner base particles. The external additive contains particles including silica and titania; the abundance ratio of titania atoms relative to silicon atoms on the outermost surface of the toner is 0.1 to 5 atm%; and the content of tin atoms relative to the total amount of the toner is 0.001 to 1 mass%.

Description

  The present invention relates to an electrostatic charge image developing toner, an electrostatic charge image developer, a toner cartridge, a developer cartridge, a process cartridge, an image forming method, and an image forming apparatus.

A method of visualizing image information through an electrostatic charge image such as electrophotography is currently used in various fields. In electrophotography, an electrostatic charge image (electrostatic latent image) is formed on a photoreceptor (image carrier) by charging and exposure processes, the electrostatic latent image is developed with a developer containing toner, and a transfer and fixing process. It is visualized through. The developer used here includes a two-component developer composed of a toner and a carrier, and a one-component developer using a magnetic toner or a non-magnetic toner alone. As a method for producing the toner, a thermoplastic resin is usually used. A kneading and pulverizing method is used in which melt-kneading is performed together with a release agent such as a pigment, a charge control agent, and wax, followed by cooling, fine pulverization, and further classification. In these toners, if necessary, inorganic and organic particles for improving fluidity and cleaning properties may be added to the toner particle surfaces.
Examples of conventional toners include toners described in Patent Documents 1 to 3.
Patent Document 1 discloses an electrostatic charge image developing toner having at least toner base particles and hydrophobic titanium oxide fine particles. The hydrophobic titanium oxide fine particles have a range of 2θ = 25.2 to 25.8 deg in X-ray diffraction. In the range of 2θ = 27.2 to 27.8 deg, the peak intensity Ia is in the range of 1800 to 2500, and the toner contains an inorganic tin (II) compound. An electrostatic charge image developing toner is disclosed which contains at least a polyester resin obtained as a catalyst.

Patent Document 2 discloses an electrophotographic toner comprising a binder resin and a colorant, wherein the binder resin is an alcohol in the presence of a monoalkyltin compound having an alkyl group having 1 to 18 carbon atoms. A polyester obtained by polycondensation of a component and a carboxylic acid component, and the total content of dialkyltin compounds and trialkyltin compounds present as impurities in the monoalkyltin compound is 2.0% by mass or less An electrophotographic toner is disclosed in which the colorant contains a metal oxide containing two or more metals.
In Patent Document 3, in a toner containing at least a binder resin made of a polyester resin and colored particles having a coloring agent and external additive fine particles, the toner has an average circularity of 0.950 to 0.00. 990, the volume-based median diameter is 4.5 to 8.0 μm, the volume-based particle size dispersion (CV _VOL value) is 15 to 25, and the metal selected from titanium, germanium, and aluminum is 10 The external additive fine particles are composed of a composite oxide containing silicon atoms and at least one of titanium atoms and aluminum atoms, and the external additive fine particles are the whole. R ₁ and abundance ratio of silicon atoms in, when the existence ratio of silicon atoms in the surface layer and R _2, the coefficient _{(R 1) / (R 2} ) is to be 1.0 or less Toner and symptoms is disclosed.

JP 2008-292822 A JP 2007-206323 A JP 2009-258681 A

  An object of the present invention is to provide an electrostatic image developing toner in which a decrease in transfer efficiency is suppressed even when a large number of sheets are printed.

The above-described problems of the present invention have been solved by means described in the following <1> and <4> to <9>. It is described below together with <2> and <3> which are preferred embodiments.
<1> Toner base particles and an external additive externally added to the toner base particles, wherein the external additive contains particles containing silica and titania, and titanium atoms relative to silicon atoms on the outermost surface of the toner An electrostatic charge image developing toner, wherein the abundance ratio is 0.1 to 5 atm% and the content of tin atoms in the whole toner is 0.001 to 1% by mass,
<2> The toner for developing an electrostatic charge image according to <1>, wherein the abundance ratio of titanium atoms to silicon atoms on the outermost surface of the toner is 1 to 5 atm%.
<3> The electrostatic charge image developing toner according to <1> or <2>, wherein the toner base particles contain polyester as a binder resin.
<4> An electrostatic image developer comprising the electrostatic image developing toner according to any one of <1> to <3> and a carrier,
<5> Toner cartridge containing the electrostatic image developing toner according to any one of <1> to <3>
<6> A developer cartridge containing the electrostatic image developer according to <4>,
<7> A process cartridge comprising a developer holder that contains the electrostatic image developer according to <4> and holds and conveys the electrostatic image developer.
<8> A latent image forming step for forming an electrostatic latent image on the surface of the image carrier, and a developing step for developing the electrostatic latent image formed on the surface of the image carrier with a developer containing toner to form a toner image. And a fixing step for fixing the toner image transferred to the surface of the transfer body, and the developer is any one of <1> to <3> An image forming method using the electrostatic image developing toner according to claim 1 or the electrostatic charge image developer according to <4>,
<9> An image carrier, a charging unit for charging the image carrier, an exposure unit for exposing the charged image carrier to form an electrostatic latent image on the surface of the image carrier, and a developer containing toner. Developing means for developing an electrostatic latent image to form a toner image, transfer means for transferring the toner image from the image carrier to the surface of the transfer target, and fixing the toner image transferred to the surface of the transfer target An image having the electrostatic charge image developing toner according to any one of <1> to <3> or the electrostatic charge image developer according to <4>. Forming equipment.

According to the inventions described in the above <1> and <2>, it is possible to provide a toner for developing an electrostatic image in which image defects are suppressed as compared with the case where the present configuration is not provided.
According to the invention described in <3>, it is possible to provide a toner for developing an electrostatic charge image in which image defects are suppressed even under high temperature and high humidity.
According to the invention described in <4> above, it is possible to provide an electrostatic charge image developer in which image defects are suppressed as compared with the case where this configuration is not provided.
According to the invention described in <5>, it is possible to provide a toner cartridge containing toner for developing an electrostatic image in which image defects are suppressed as compared with the case where the present configuration is not provided.
According to the invention described in <6> above, it is possible to provide a developer cartridge containing an electrostatic charge image developer in which image defects are suppressed as compared with the case where this configuration is not provided.
According to the invention described in <7> above, it is possible to provide a process cartridge containing an electrostatic charge image developer in which image defects are suppressed as compared with the case where this configuration is not provided.
According to the invention described in <8> above, it is possible to provide an image forming method in which image defects are suppressed as compared with a case where the present configuration is not provided.
According to the invention described in <9>, it is possible to provide an image forming apparatus in which image defects are suppressed as compared with the case where the present configuration is not provided.

Hereinafter, the present embodiment will be described.
In the present embodiment, the description “A to B” represents not only a range between A and B but also a range including A and B at both ends thereof. For example, if “A to B” is a numerical value range, it represents “A or more and B or less” or “A or less and B or more”. Further, “mass%” and “part by mass” have the same meanings as “weight%” and “part by weight”, respectively.

1. Toner for developing electrostatic image The toner for developing an electrostatic image of the present embodiment (hereinafter also simply referred to as “toner”) contains toner base particles and an external additive externally added to the toner base particles. The external additive contains particles containing silica and titania (hereinafter also referred to as “composite particles”), and the abundance ratio of titanium atoms to silicon atoms on the outermost surface of the toner is 0.1 to 5 atm%. The tin atom content in the entire toner is 0.001 to 1 mass%.

A tin (Sn) compound is widely used as a catalyst for synthesizing a binder resin of a toner because it has excellent catalytic activity and can synthesize a resin having a narrow molecular weight distribution. Moreover, it is used not only as a catalyst but also as an additive for obtaining a high molecular weight resin (for example, see JP-A-7-126306). On the other hand, tin has a low electric resistance, and therefore, if it remains in the toner, it causes fogging of charge and causes fogging.
When silica particles are used as an external additive to the toner base particles containing tin atoms, the silica particles have high resistance, and thus charge leakage is suppressed, but charge exchange is low and mixing is possible. There's a problem. As a result, when a large number of sheets are printed, low-charge toner is generated and fogging occurs. In addition, titania has excellent charge exchange properties because of its low resistance, but because of its low resistance, when titania particles are used as an external additive, charge leakage occurs, resulting in fogging. Occur.
As a result of intensive studies, the present inventors have used specific composite particles as external additives for toner base particles containing tin atoms, thereby suppressing the occurrence of fogging due to charge leakage and suppressing image defects. It was found that a toner for developing an electrostatic image was obtained.

Although the detailed mechanism of action is unknown, it is estimated as follows.
Tin (Sn) and silicon (Si) are homologous elements on the periodic table and have very close electronegativity. Specifically, Si / Sn = 1.90 / 1.96. Therefore, it is considered that the inflow of electric charge from Si to Sn hardly occurs. The composite particles used in the present embodiment can maintain the charge exchange property of titania while covering the titania surface with silica, while suppressing charge leakage, and even when a large number of sheets are printed, fogging is generated. Is suppressed, and image defects are considered to be suppressed.
Furthermore, since Sn and Si have extremely weak electrical interaction, the composite particles used in this embodiment are considered to have low adhesion to the toner base particle surface. For this reason, even when the composite particles are embedded in the toner surface, the external additive is liberated during the transfer, and the transfer assisting function is exhibited, and it is estimated that the decrease in transfer efficiency is suppressed even when printing a large number of sheets. The
Hereinafter, each component and physical property value constituting the toner will be described in detail.

(Abundance ratio of titanium atoms to silicon atoms on the outermost surface of the toner)
In the toner according to the exemplary embodiment, the abundance ratio of titanium atoms to silicon atoms on the outermost surface of the toner is 0.01 atm% (atomic%) to 5 atm% (atomic%). That is, when the abundance of silicon atoms on the outermost surface of the toner is A (atm%) and the abundance of titanium atoms is B (atm%), it means that (B / A) × 100 is 5 atm% or less. .
When the ratio of titanium atoms to silicon atoms on the outermost surface of the toner is 0.1 atm% or more, the charge exchange function is sufficient and image fogging is suppressed. If it is 5 atm% or less, charge leakage is suppressed and image fogging is suppressed.
The abundance ratio is 0.1 atm% or more, preferably 0.3 atm% or more, and more preferably 1 atm% or more. With the above aspect, an image with few image quality defects can be obtained even when a large number of sheets are printed.

The abundance ratio of titanium atoms to silica atoms on the outermost surface of the toner is measured by X-ray photoelectron spectroscopy (XPS). The measurement method is not particularly limited as long as it is an X-ray photoelectron spectroscopic analysis method. Specifically, an XPS measurement is performed using an X-ray photoelectron spectroscopic analyzer (JPS9000MX, manufactured by JEOL Ltd.). The measurement is performed under the measurement conditions of an acceleration voltage of 10 kV and a current value of 30 mA.
In XPS measurement, it is possible to measure the element distribution on the very surface (several nm) of a substance.

That the abundance ratio of titanium atoms to silicon atoms on the toner surface is 5 atm% or less means that most of the surface (surface layer) of the composite particles is silica and there is little titania exposed on the surface.
In some cases, the toner base particles contain a small amount of titanium atoms as a catalyst or the like.

(Content of tin atom in the total toner)
In the present embodiment, the content of tin atoms in the entire toner is 0.001 to 1% by mass.
The content of tin atoms in the entire toner can be determined by qualitative and quantitative analysis of all elements by fluorescent X-ray analysis. Specifically, first, 6 g of toner is compression-molded under a pressure condition of 20 tons and 30 seconds with a pressure molding machine to produce a molded product having a diameter of 50 mm. The produced molded product is measured by fluorescent X-ray (ZSX Primus II) of Rigaku Corporation. The applied voltage is 30 kV, the applied current is 100 mA, and the spectral crystal is measured with PET.

(External additive)
The toner of this embodiment contains an external additive externally added to toner base particles, and the external additive contains particles (composite particles) containing silica and titania.
The toner according to the exemplary embodiment may include one kind or two or more kinds of particles containing silica and titania. Further, the toner of the present exemplary embodiment may include an external additive other than particles including silica and titania.
As an external addition method of the external additive in the toner of the exemplary embodiment, for example, a method in which the toner base particles and the external additive are mixed by using a Henschel mixer or a V blender is exemplified. In addition, when the toner base particles are produced by a wet method, external addition can also be performed by a wet method.

<Particles containing silica and titania>
The toner of the exemplary embodiment includes particles (composite particles) containing silica and titania as external additives. By including particles containing silica and titania as external additives, fogging is suppressed even when a large number of sheets are printed by suppressing charge leakage while maintaining charge exchange properties.
In the composite particles, when the titania is completely covered with silica, the charge exchange property is not sufficiently maintained. The partial coating can be confirmed by observing the toner slice with a transmission electron microscope (TEM).
The composite particles may contain components other than silica and titania as long as the effects are not impaired. When other components are contained, the total content of silica and titania may be 50% by mass or more of the composite particles, and may be 75% by mass or more, or 90% by mass or more. From the viewpoint of the suppression of fogging, it is preferable that the composite particles consist only of silica and titania.

In the toner according to the exemplary embodiment, the content of the composite particle is not particularly limited, but is preferably 0.3 to 10% by mass, and preferably 0.5 to 5% by mass with respect to the total mass of the toner. Is more preferable, and it is still more preferable that it is 0.8-2.0 mass%.
In addition, when other external additives described later are included, the content of the composite particles may be 50% by mass or more with respect to all external additives including other external additives, and even if 75% by mass or more, 90% by mass. % Or more. From the viewpoint of suppression of fogging, it is preferable to contain only 100% by mass, that is, only the composite particles as an external additive.

  In the toner of the exemplary embodiment, the number average primary particle diameter of the composite particles is preferably 10 to 600 nm, more preferably 20 to 300 nm, and still more preferably 20 to 200 nm. When the number average primary particle diameter is 10 nm or more, the embedding in the toner is suppressed, and an effect can be obtained even when printing many sheets. Further, when it is 600 nm or less, the adhesiveness to the toner is excellent, and the image defect due to the liberation of the external additive is suppressed.

The method for producing composite particles is not particularly limited, but includes a step of preparing an alkali catalyst solution containing an alkali catalyst in a solvent containing alcohol, and a metal alkoxide monomer and the alkali catalyst in the alkali catalyst solution. It is preferable that it is a manufacturing method including the process of supplying and producing | generating particle | grains.
The method for preparing the metal alkoxide monomer may be a method of mixing a tetraalkoxytitanium monomer in a tetraalkoxysilane monomer, a method of mixing a tetraalkoxysilane monomer in a tetraalkoxytitanium monomer, or dropping a tetraalkoxysilane. Alternatively, tetraalkoxytitanium may be dropped and particle-grown after particle formation, or tetraalkoxysilane may be dropped and particle-grown after tetraalkoxytitanium is dropped and granulated.

[Preparation process]
The method for producing composite particles preferably includes a step (preparation step) of preparing an alkali catalyst solution containing an alkali catalyst in a solvent containing alcohol.
A preparation process should just prepare the solvent containing alcohol, add an alkali catalyst to this, and prepare an alkali catalyst solution.
The solvent containing alcohol may be a solvent of alcohol alone or, if necessary, ketones such as water, acetone, methyl ethyl ketone, methyl isobutyl ketone, cellosolves such as methyl cellosolve, ethyl cellosolve, butyl cellosolve, cellosolve acetate, It may be a mixed solvent with other solvents such as ethers such as dioxane and tetrahydrofuran. In the case of a mixed solvent, the amount of alcohol relative to the other solvent is preferably 80% by mass or more, and more preferably 90% by mass or more.
Examples of the alcohol include lower alcohols such as methanol and ethanol.
The alkali catalyst is a catalyst for accelerating the reaction (hydrolysis reaction, condensation reaction) of the metal alkoxide of tetraalkoxysilane and tetraalkoxytitanium, for example, a base such as ammonia, urea, monoamine, quaternary ammonium salt, etc. And ammonia is particularly preferable.
The concentration (content) of the alkali catalyst is preferably 0.6 mol / L or more and 0.85 mol / L. Within the above range, when tetraalkoxysilane is supplied in the particle generation process, the dispersibility in the growth process of the generated core particles becomes stable, the generation of coarse aggregates such as secondary aggregates is suppressed, and gelation occurs. It can suppress that it becomes a shape. In addition, the density | concentration of an alkali catalyst is a density | concentration with respect to an alcohol catalyst solution (an alkali catalyst + solvent containing alcohol).

[Particle generation process]
The method for producing composite particles preferably includes a step of supplying particles of the metal alkoxide monomer and the alkali catalyst into the alkali catalyst solution to generate particles (particle generation step).
In the particle generation step, a metal alkoxide and an alkali catalyst are respectively supplied into an alkali catalyst solution, and the metal alkoxide is reacted (hydrolysis reaction, condensation reaction) in the alkali catalyst solution to generate composite silica particles. It is preferable that it is a process to perform. In this particle generation step, metal alkoxide core particles are generated at the initial supply stage of the metal alkoxide, and then composite silica particles are generated through the growth of the core particles. For example, the supply amount of the metal alkoxide is preferably 0.001 mol / (mol · min) or more and 0.01 mol / (mol · min) or less with respect to the number of moles of alcohol in the alkali catalyst solution.
By setting the supply amount of the metal alkoxide within the above range, the generation of coarse aggregates is small and atypical silica particles are easily generated. The supply amount of the metal alkoxide indicates the number of moles of metal alkoxide supplied per minute with respect to 1 mol of alcohol in the alkali catalyst solution.

On the other hand, examples of the alkali catalyst supplied into the alkali catalyst solution include those exemplified above. The alkali catalyst to be supplied may be the same type as the alkali catalyst previously contained in the alkali catalyst solution, or may be a different type, but is preferably the same type. The supply amount of the alkali catalyst is preferably 0.1 mol or more and 0.4 mol or less with respect to 1 mol of the total supply amount supplied per minute of the metal alkoxide. Here, in the particle generation step, the metal alkoxide and the alkali catalyst are supplied into the alkali catalyst solution, respectively. This supply method may be a continuous supply method or an intermittent supply. It may be a system to do.
In the particle generation step, the temperature in the alkali catalyst solution (temperature at the time of supply) is preferably 5 ° C. or more and 50 ° C. or less, for example.

Through the above steps, composite particles are obtained. In this state, the obtained composite particles can be obtained in the form of a dispersion, but may be used as a composite particle dispersion as it is, or may be used by removing the solvent as a powder of composite particles. When used as a dispersion, the solid content concentration may be adjusted by diluting or concentrating with water or alcohol as necessary. Further, the composite particle dispersion may be used after solvent substitution with other water-soluble organic solvents such as alcohols, esters, and ketones.
On the other hand, when used as a powder of composite particles, it is necessary to remove the solvent from the dispersion liquid. As this solvent removal method, 1) After removing the solvent by filtration, centrifugation, distillation, etc., a vacuum dryer And a known method such as a method of drying by a shelf dryer, 2) a method of directly drying a slurry by a fluidized bed dryer, a spray dryer or the like. Although a drying temperature is not specifically limited, It is preferable that it is 200 degrees C or less.
The dried composite particles are preferably crushed and sieved as necessary to remove coarse particles and aggregates. The crushing method is not particularly limited, and examples thereof include a method performed by a dry pulverizer such as a jet mill, a vibration mill, a ball mill, and a pin mill. Examples of the sieving method include a method using a known method such as a vibration sieve or a wind sieving machine.

  The composite particles may be used by hydrophobizing the surface of the composite particles with a hydrophobizing agent. Examples of the hydrophobizing agent include known organosilicon compounds having an alkyl group (eg, methyl group, ethyl group, propyl group, butyl group). Specific examples include, for example, silazane compounds (eg, methyl trimethyl compound). Silane compounds such as methoxysilane, dimethyldimethoxysilane, trimethylchlorosilane, and trimethylmethoxysilane, hexamethyldisilazane, tetramethyldisilazane, and the like. The hydrophobizing agent may be used alone or in combination. Among these hydrophobizing agents, organosilicon compounds having a trimethyl group such as trimethylmethoxysilane and hexamethyldisilazane are suitable. The amount of the hydrophobizing agent used is not particularly limited, but in order to obtain a hydrophobizing effect, for example, it is preferably 1% by mass or more and 100% by mass or less, preferably 5% by mass with respect to the composite particles. More preferably, it is 80 mass% or less.

As a method for obtaining a hydrophobic composite particle dispersion that has been subjected to a hydrophobizing treatment with a hydrophobizing agent, for example, a necessary amount of a hydrophobizing agent is added to the composite particle dispersion, and 30 to 80 ° C. with stirring. There is a method in which the particles are subjected to a hydrophobization treatment by reacting in the above temperature range to obtain a hydrophobic composite particle dispersion.
On the other hand, as a method for obtaining hydrophobic composite particles of powder, a method of obtaining a hydrophobic composite particle dispersion by the above method and then drying by the above method to obtain a powder of hydrophobic composite particles, a composite particle dispersion Was dried to obtain a powder of hydrophilic composite particles, and then a hydrophobic treatment agent was added and subjected to a hydrophobic treatment to obtain a powder of hydrophobic composite particles, and a hydrophobic composite particle dispersion was obtained. Thereafter, after drying to obtain a powder of hydrophobic composite particles, a method of obtaining a powder of hydrophobic composite particles by adding a hydrophobizing agent and applying a hydrophobization treatment, and the like, can be mentioned. Here, as a method of hydrophobizing the composite particles of the powder, the hydrophilic composite particles of the powder are stirred in a processing tank such as a Henschel mixer or a fluidized bed, and a hydrophobizing agent is added thereto, There is a method in which the hydrophobizing agent is gasified by heating the inside to react with silanol groups on the surface of the powder composite particles. Although processing temperature is not specifically limited, For example, it is preferable that it is 80 to 300 degreeC, and it is more preferable that it is 120 to 200 degreeC.

<Other external additives>
The toner of the exemplary embodiment may include an external additive other than the composite particle (also referred to as “other external additive”) as long as the effect is not impaired.
Other external additives are not particularly limited, and known inorganic particles and organic particles are used as toner external additives. For example, silica, alumina, titanium oxide (titanium oxide, metatitanic acid, etc.), oxidation, etc. Examples thereof include inorganic particles such as cerium, zirconia, calcium carbonate, magnesium carbonate, calcium phosphate, and carbon black, and resin particles such as vinyl resin, polyester resin, and silicone resin. Further, the other external additives may be those that have been subjected to the hydrophobic treatment described above.
The average primary particle size of other external additives is preferably 3 to 500 nm, more preferably 5 to 100 nm, still more preferably 5 to 50 nm, and particularly preferably 5 to 40 nm. .

(Toner mother particles)
Specifically, the toner base particles include, for example, a binder resin and, if necessary, a colorant, a release agent, and other additives.

<Binder resin>
The binder resin is not particularly limited. For example, styrenes such as styrene, parachlorostyrene, and α-methylstyrene; methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, acrylic Esters having vinyl groups such as lauryl acid, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate; vinyl nitriles such as acrylonitrile and methacrylonitrile Vinyl ethers such as vinyl methyl ether and vinyl isobutyl ether; vinyl ketones such as vinyl methyl ketone, vinyl ethyl ketone and vinyl isopropenyl ketone; single quantities of polyolefins such as ethylene, propylene and butadiene Homopolymer consisting of, or copolymers obtained by combining two or more of these, even mixtures thereof. In addition, epoxy resins, polyester resins, polyurethane resins, polyamide resins, cellulose resins, polyether resins, etc., non-vinyl condensation resins, or a mixture of these with the vinyl resin, or vinyl monomers in the presence of these resins Examples thereof include a graft polymer obtained by polymerization.
Styrene resin, (meth) acrylic resin, and styrene- (meth) acrylic copolymer resin are obtained by known methods, for example, by combining styrene monomers and (meth) acrylic acid monomers alone or in appropriate combination. It is done. “(Meth) acryl” is an expression including both “acryl” and “methacryl”.
The polyester resin can be obtained by selecting and combining suitable ones from a dicarboxylic acid component and a diol component and synthesizing them using a conventionally known method such as a transesterification method or a polycondensation method.

  When using a styrene resin, a (meth) acrylic resin or a copolymer resin thereof as a binder resin, the weight average molecular weight Mw is 20,000 or more and 100,000 or less, and the number average molecular weight Mn is 2,000 or more and 30,000 or less. It is preferable to use the thing of the range. On the other hand, when a polyester resin is used as the binder resin, a resin having a weight average molecular weight Mw of 5,000 or more and 40,000 or less and a number average molecular weight Mn of 2,000 or more and 10,000 or less may be used. preferable.

  The glass transition temperature of the binder resin is desirably in the range of 40 ° C. or higher and 80 ° C. or lower. When the glass transition temperature is in the above range, the minimum fixing temperature is easily maintained.

In this embodiment, it is preferable to use a tin-containing catalyst such as tin, tin formate, tin oxalate, tetraphenyltin, dibutyltin dichloride, dibutyltin oxide, and diphenyltin oxide as a polymerization catalyst in the synthesis of the binder resin.
In particular, when a polyester resin that is a binder resin is synthesized, it is preferable to use a tin-containing catalyst as a polycondensation catalyst.
By controlling the amount of the tin-containing catalyst added, the content of tin element relative to the entire toner is controlled.

The tin-containing catalyst includes an organic tin-containing catalyst and an inorganic tin-containing catalyst. An organotin-containing catalyst is a compound having a Sn—C bond, and an inorganic tin-containing catalyst is a compound having no Sn—C bond.
The tin-containing catalyst includes di-type, tri-type, and tetra-type, and the di-type is preferably used. An inorganic tin-containing catalyst is preferred.
As the tin-containing catalyst, for example, tin dialkylate, tin dihexanoate, dioctanoate, tin distearate, etc., unbranched alkyl carboxylate, tin neopentyrate, di (2-ethylhexyl) ate (dioctylate, Stannous alkylcarboxylates such as stannous octylate), tin carboxylates such as tin oxalate, dialkoxytin such as dioctyloxytin and distearoxytin, tin halides such as tin chloride and tin bromide , Tin oxide, tin sulfate, dimethyltin dilaurate, dibutyltin dilaurate, and the like. In particular, tin dioctanoate, tin distearate, tin oxide, dilaurin sun dimethyltin, and dibutyltin dilaurate are preferred.

In addition, when synthesizing the binder resin, a tin compound may be added to promote the high molecular weight of the resin. Specifically, a stannous compound represented by the following formula (1) should be added. Is exemplified. Reference is made to the resin production method described in JP-A-7-126306.
(R-COO-) ₂ Sn (1)
In formula (1), R represents an alkyl group having 5 to 12 carbon atoms.

<Colorant>
The colorant is not particularly limited as long as it is a known colorant. For example, carbon black such as furnace black, channel black, acetylene black, and thermal black, inorganic pigments such as bengara, bitumen, and titanium oxide, fast yellow, disazo Azo pigments such as yellow, pyrazolone red, chelate red, brilliant carmine, para brown, phthalocyanine pigments such as copper phthalocyanine, metal-free phthalocyanine, flavantron yellow, dibromoanthrone orange, perylene red, quinacridone red, dioxazine violet Examples thereof include cyclic pigments. As the colorant, a surface-treated colorant may be used as necessary, or it may be used in combination with a dispersant.
A plurality of colorants may be used in combination.
As content of a coloring agent, the range of 1 mass% or more and 30 mass% or less is desirable with respect to the total mass of binder resin.

<Release agent>
Examples of mold release agents include hydrocarbon waxes; natural waxes such as carnauba wax, rice wax, and candelilla wax; synthetic or mineral / petroleum waxes such as montan wax; ester types such as fatty acid esters and montanic acid esters. Wax; and the like, but is not limited thereto.
The melting point of the release agent is preferably 50 ° C. or higher, and more preferably 60 ° C. or higher, from the viewpoint of storage stability. Further, from the viewpoint of offset resistance, the temperature is desirably 110 ° C. or less, and more desirably 100 ° C. or less. The content of the release agent is preferably 1% by mass to 15% by mass, more preferably 2% by mass to 12% by mass, and still more preferably 3% by mass to 10% by mass.

<Other additives>
Examples of other additives include magnetic substances, charge control agents, inorganic powders, and the like.

<Manufacturing method>
The toner base particles used in the exemplary embodiment are not particularly limited by the production method, and a known method can be used. Specific examples include the following methods.
The production of the toner base particles is obtained, for example, by a kneading and pulverizing method in which a binder resin, a colorant, a release agent, and a charge control agent, if necessary, are kneaded, pulverized, and classified; To change the shape of the particles by mechanical impact force or thermal energy; dispersion of emulsified binder resin, dispersion of colorant, release agent, and charge control agent as required An emulsion aggregation method in which toner particles are obtained by mixing, aggregating and heating and fusing the solution; emulsion polymerization of a polymerizable monomer of a binder resin, and a formed dispersion, a colorant, a release agent, and , An emulsion polymerization aggregation method to obtain toner particles by mixing with a dispersion such as a charge control agent, if necessary, and then fusing and heat-fusing; a polymerizable monomer for obtaining a binder resin, a colorant, A suspension polymerization method in which a release agent and, if necessary, a solution such as a charge control agent are suspended in an aqueous solvent for polymerization; Resin and a colorant, releasing agent, and dissolution suspension method and granulated with a solution such as a charge control agent is suspended in an aqueous solvent optionally; or the like can be used. In addition, a manufacturing method may be performed in which the toner base particles obtained by the above method are used as a core, and aggregated particles are further adhered and heat-fused to have a core-shell structure.
Among these, the toner of the exemplary embodiment is preferably a toner (emulsion aggregation toner) obtained by an emulsion aggregation method or an emulsion polymerization aggregation method.

  The toner base particles produced as described above preferably have a volume average particle diameter in the range of 2 to 8 μm, and more preferably in the range of 3 to 7 μm. When the volume average particle size is 2 μm or more, the toner has good fluidity, and sufficient chargeability is imparted from the carrier, so that fogging in the background portion and density reproducibility are unlikely to occur. . Further, when the volume average particle size is 8 μm or less, the effect of improving the reproducibility, gradation and graininess of fine dots is good, and a high-quality image can be obtained. The volume average particle size is measured with Coulter Multisizer II (manufactured by Beckman Coulter, Inc.).

  The toner base particles are preferably pseudo-spherical from the viewpoint of improving developability and transfer efficiency and improving image quality. The sphericity of the toner base particles can be expressed by using the shape factor SF1 of the following formula, but the average value (average shape factor) of the shape factor SF1 of the toner base particles used in this embodiment is 160. Is preferably in the range of 115 or more and less than 155, and more preferably in the range of 120 or more and less than 140. When the average value of the shape factor SF1 is less than 160, good transfer efficiency is obtained and the image quality is excellent.

In the above formula, ML represents the maximum length of each toner base particle, and A represents the projected area of each toner base particle.
The average value of the shape factor SF1 (average shape factor) is obtained by taking 1,000 toner images magnified 250 times from an optical microscope to an image analyzer (LUZEX III, manufactured by Nireco Corporation), and the maximum From the length and the projected area, the value of the SF1 is obtained for each particle and averaged.

2. Electrostatic Image Developer The electrostatic image developing toner of the present embodiment is suitably used as an electrostatic image developer.
The electrostatic image developer of this embodiment is not particularly limited except that it contains the electrostatic image developing toner of this embodiment, and can take an appropriate component composition depending on the purpose. When used alone, the toner for developing an electrostatic image of this embodiment is prepared as a one-component electrostatic image developer, and when used in combination with a carrier, it is prepared as a two-component electrostatic image developer. .
As a one-component developer, a method in which a charged toner is formed by frictional charging with a developing sleeve or a charging member, and development is performed according to an electrostatic latent image is also applied.

  In the present embodiment, the development method is not particularly defined, but the two-component development method is preferable. Further, the carrier is not particularly defined as long as the above conditions are satisfied. Examples of the carrier core material include magnetic metals such as iron, steel, nickel, and cobalt, alloys of these with manganese, chromium, rare earth, and the like, and Magnetic oxides such as ferrite and magnetite are mentioned, and from the viewpoint of core material surface properties and core material resistance, ferrite, particularly alloys with manganese, lithium, strontium, magnesium and the like are preferably mentioned.

  The carrier used in this embodiment is preferably formed by coating the surface of the core material with a resin. There is no restriction | limiting in particular as said resin, According to the objective, it selects suitably. Moreover, it is preferable that the resin film and / or electroconductive particle are disperse | distributed in the said resin in the film by the said resin. Examples of the resin particles include thermoplastic resin particles and thermosetting resin particles. The average particle size of the resin particles is preferably 0.1 to 2 μm, and more preferably 0.2 to 1 μm. When the average particle size of the resin particles is 0.1 μm or more, the resin particles are excellent in dispersibility in the coating, whereas when the average particle size is 2 μm or less, the resin particles are not easily dropped from the coating.

The method for forming the coating is not particularly limited. For example, the resin particles such as crosslinkable resin particles and / or the conductive particles, and a styrene acrylic resin, a fluorine resin, a silicone resin as a matrix resin, etc. And a method of using a film-forming solution containing the above resin in a solvent.
Specifically, the carrier core material is immersed in the film forming liquid, a spray method in which the film forming liquid is sprayed on the surface of the carrier core material, and the carrier core material is floated by flowing air And kneader coater method in which the film forming solution is mixed and the solvent is removed. Among these, the kneader coater method is preferable in the present embodiment.

  The mixing ratio of the toner and the carrier of this embodiment in the two-component electrostatic image developer is preferably 2 to 10 parts by mass of the toner with respect to 100 parts by mass of the carrier. Moreover, the preparation method of a developing agent is not specifically limited, For example, the method of mixing with a V blender etc. is mentioned.

3. Image Forming Method The electrostatic image developer (electrostatic image developing toner) is used in an image forming method of an electrostatic image developing system (electrophotographic system).
The image forming method of the present embodiment includes a latent image forming step of forming an electrostatic latent image on the surface of the image carrier, and developing the electrostatic latent image formed on the surface of the image carrier with a developer containing toner. A developing step for forming an image, a transferring step for transferring the toner image to the surface of the transfer member, and a fixing step for fixing the toner image transferred to the surface of the transfer member. The toner for developing an electrostatic charge image of the form or the electrostatic charge image developer of the present embodiment is used.
The image forming method of the present embodiment preferably includes a cleaning step in addition to the above steps.

Each of the above steps is a general step per se, and is described in, for example, JP-A-56-40868 and JP-A-49-91231. Note that the image forming method of the present embodiment can be carried out by using a known image forming apparatus such as a copying machine or a facsimile machine.
The electrostatic latent image forming step is a step of forming an electrostatic latent image on an image carrier (photoconductor).
The developing step is a step of developing the electrostatic latent image with a developer layer on a developer holding member to form a toner image. The developer layer is not particularly limited as long as it contains the electrostatic image developing toner of this embodiment.
The transfer step is a step of transferring the toner image onto a transfer target. Examples of the transfer medium in the transfer process include an intermediate transfer medium and a recording medium such as paper.
In the fixing step, for example, there is a method of forming a copy image by fixing the toner image transferred onto the transfer paper by a heating roller fixing device in which the temperature of the heating roller is set to a constant temperature.
The cleaning step is a step of removing the electrostatic charge image developer remaining on the image carrier.
Further, the image forming method of the present embodiment preferably includes the cleaning step, and more preferably includes a step of removing the electrostatic charge image developer remaining on the image carrier with a cleaning blade.
As the recording medium, known media can be used, for example, paper used for electrophotographic copying machines, printers, OHP sheets, etc. For example, the surface of plain paper is made of resin, etc. Coated coated paper, art paper for printing, and the like can be suitably used.

  The image forming method of the present embodiment may further include a recycling step. The recycling step is a step of transferring the electrostatic charge image developing toner collected in the cleaning step to a developer layer. The image forming method including the recycling process is performed using an image forming apparatus such as a toner recycling system type copying machine or facsimile machine. Further, the present invention may be applied to a recycling system in which the cleaning process is omitted and toner is collected simultaneously with development.

4). Image Forming Apparatus The image forming apparatus according to the present embodiment forms an electrostatic latent image on the surface of the image carrier by exposing the image carrier, charging means for charging the image carrier, and exposing the charged image carrier. Exposure means for developing, developing means for developing the electrostatic latent image with a developer containing toner to form a toner image, transfer means for transferring the toner image from the image carrier to the surface of the transfer target, Fixing means for fixing the toner image transferred to the surface of the transfer target, and using the electrostatic image developing toner of the present embodiment or the electrostatic image developer of the present embodiment as the developer. Features.
The image forming apparatus of the present embodiment is not particularly limited as long as it includes at least the image holding member, the charging unit, the exposure unit, the developing unit, and the transfer unit as described above, but other necessary. Depending on the situation, a fixing means, a cleaning means, a static elimination means and the like may be included.
In the transfer unit, the transfer may be performed twice or more using an intermediate transfer member. Examples of the transfer medium in the transfer unit include an intermediate transfer medium and a recording medium such as paper.

The image carrier and each of the above-described units can preferably use the configurations described in the respective steps of the image forming method. As each of the above-described means, a known means in the image forming apparatus can be used. In addition, the image forming apparatus according to the present embodiment may include means and devices other than the above-described configuration. Further, the image forming apparatus according to the present embodiment may simultaneously perform a plurality of the above-described means.
The image forming apparatus according to the present exemplary embodiment preferably includes a cleaning unit that removes the electrostatic charge image developer remaining on the image carrier.
Examples of the cleaning means include a cleaning blade and a cleaning brush, and a cleaning blade is preferable.
Preferred examples of the cleaning blade material include urethane rubber, neoprene rubber, and silicone rubber.

5. Toner Cartridge, Developer Cartridge, and Process Cartridge The toner cartridge of the present embodiment is a toner cartridge that contains at least the electrostatic image developing toner of the present embodiment.
The developer cartridge of this embodiment is a developer cartridge that contains at least the electrostatic charge image developer of this embodiment.
The process cartridge according to the present embodiment includes a developing unit that develops the electrostatic latent image formed on the surface of the image carrier with the electrostatic image developing toner or the electrostatic image developer to form a toner image. And at least one selected from the group consisting of an image carrier, a charging unit for charging the surface of the image carrier, and a cleaning unit for removing the toner remaining on the surface of the image carrier, This is a process cartridge containing at least the electrostatic image developing toner of the present embodiment or the electrostatic image developer of the present embodiment.

The toner cartridge of this embodiment is preferably detachable from the image forming apparatus. That is, in the image forming apparatus having a configuration in which the toner cartridge can be attached and detached, the toner cartridge of the present embodiment in which the toner of the present embodiment is stored is preferably used.
The developer cartridge of the present embodiment is not particularly limited as long as it contains the electrostatic charge image developer containing the electrostatic charge image developing toner of the present embodiment. The developer cartridge is, for example, attached to and detached from an image forming apparatus including a developing unit, and includes the electrostatic image developer according to the present embodiment as a developer to be supplied to the developing unit. Is stored.
The developer cartridge may be a cartridge that stores toner and a carrier, or may be a cartridge that stores toner alone and a cartridge that stores a carrier separately.
It is preferable that the process cartridge of the present embodiment is attached to and detached from the image forming apparatus.
In addition, the process cartridge according to the present embodiment may include other members such as a static elimination unit as necessary.
As the toner cartridge and the process cartridge, known configurations may be adopted. For example, Japanese Patent Application Laid-Open Nos. 2008-209489 and 2008-233736 are referred to.

  Hereinafter, although this embodiment is described in detail with examples, this embodiment is not limited in any way. In the following description, “parts” and “%” indicate “parts by mass” and “% by mass” unless otherwise specified.

<Measuring method of abundance ratio of titanium atom to silicon atom on toner outermost surface>
The abundance ratio of titanium atoms to silicon atoms on the outermost surface of the toner is measured by XPS measurement using an X-ray photoelectron spectrometer (JPS 9000 MX, manufactured by JEOL Ltd.) under measurement conditions of an acceleration voltage of 10 kV and a current value of 30 mA. did.

<Method for measuring the content of tin atoms in the entire toner>
As a sample pretreatment for measurement, 6 g of toner was compression molded under a pressure of 20 t for 30 seconds with a pressure molding machine to produce a molded product having a diameter of 50 mm. The produced molded product was measured by X-ray fluorescence (ZSX Primus II) manufactured by Rigaku Corporation.

<Method for Measuring Volume Average Particle Diameter of Toner Base Particle>
The volume average particle diameter of the toner base particles was measured using Coulter Multisizer II (manufactured by Beckman Coulter, Inc.). As the electrolytic solution, ISOTON-II (manufactured by Beckman Coulter, Inc.) was used.
As a measuring method, first, 0.5 mg to 50 mg of a measurement sample is added to 2 ml of a 5% aqueous solution of a surfactant, preferably sodium alkylbenzenesulfonate as a dispersant, and this is added to 100 ml to 150 ml of the electrolytic solution. Added. The electrolytic solution in which the measurement sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 minute, and the particle size is 2.0 μm or more and 60 μm or less using the Coulter Multisizer II with an aperture having an aperture diameter of 100 μm. The particle size distribution of particles in the range was measured. The number of particles to be measured was 50,000.
For the divided particle size range (channel), draw the cumulative distribution from the smaller diameter side with respect to the divided particle size range (channel), and define the 50% cumulative particle size as the heavy average particle size or volume average particle size, respectively. To do.

<Measurement of resin particle in resin dispersion or glass transition point of resin>
A differential scanning calorimeter (manufactured by Shimadzu Corporation, DSC50) was used to measure the glass transition temperature Tg of the resin.

<Preparation of Composite Particle 1 Containing Silica and Titania>
To a glass reaction vessel equipped with a stirrer, a dropping nozzle, and a thermometer, 400 parts of methanol and 66 parts of 10% aqueous ammonia (NH ₄ OH) were added and mixed to obtain an alkali catalyst solution. The amount of catalyst in the alkaline catalyst solution at this time: the amount of NH ₃ (NH ₃ / (NH ₃ + methanol + water)) was 0.68 mol / L. Further, 0.1% of tetramethoxysilane was added to tetrabutoxytitanium to prepare a metal alkoxide mixed monomer, and after adjusting the alkali catalyst solution to 20 ° C., 200 parts of metal alkoxide mixed monomer and 3 parts were stirred. 158 parts of 8% ammonia water (NH ₄ OH) and the flow rate adjusted so that the amount of NH ₃ is 0.27 mol per mol of the total amount of metal alkoxide mixed monomer supplied per minute At the same time, the addition was started and the mixture was dropped over 60 minutes to obtain a suspension of silica particles. However, the supply amount of the metal alkoxide mixed monomer was 0.0017 mol / (mol · min) with respect to the number of moles of alcohol in the alkali catalyst solution.
300 parts of this silica slurry was distilled off by heating distillation, and after adding 300 parts of pure water, it was dried with a freeze dryer to obtain titania particles (composite particles) coated with silica.
Further, 7 parts of hexamethyldisilazane was added to 35 parts of the titania particles coated with silica and reacted at 150 ° C. for 2 hours to obtain titania particles (composite particles 1) coated with hydrophobic silica. In addition, it was confirmed by observation of the section | slice by TEM that it was partially coat | covered with the silica.

<Preparation of particles (composite particles) 2 to 5 containing silica and titania>
The amount of tetramethoxysilane added to tetrabutoxytitanium was changed as shown in Table 1 to obtain composite particles 2-5.
In addition, regarding the production conditions, the composite particle 2 was the same as the production of the composite particle 1. The composite particle 3 was the same as the preparation of the composite particle 1 except that the alkaline catalyst solution was set to 35 ° C. In the composite particle 4, it was the same as that of the composite particle 1 except that the alkaline catalyst solution was 55 ° C. The composite particle 5 was the same as the composite particle 1 except that the alkaline catalyst solution was set to 70 ° C.
The number average primary particle size of each particle was measured using a laser diffraction particle size distribution measuring device (LA-700: manufactured by Horiba, Ltd.). Add 2g of measurement sample to 50ml of 5% aqueous solution of sodium alkylbenzene sulfonate, disperse for 2 minutes with an ultrasonic disperser (1,000Hz), prepare the sample, and put it into the cell until it has an appropriate concentration Then, wait for about 2 minutes, and measure when the concentration in the cell is almost stable. The obtained particle size for each channel was accumulated from the smaller particle size, and the number average particle size was determined when the accumulation reached 50%.

<Preparation of Composite Particle 6>
The composite particles 6 were produced by a vapor phase method using steam. The gas phase method is obtained by the following methods (1) to (4).
(1) First, a silicon atom source, a titanium atom source, and an aluminum atom source are introduced from a raw material inlet and heated in an evaporator to be vaporized to produce silicon vapor, titanium vapor, and aluminum vapor. obtain.
(2) Next, these vapors are introduced into a mixing chamber together with an inert gas such as nitrogen, and dry air and / or oxygen gas and hydrogen gas are mixed at a predetermined ratio to obtain a mixed gas, This mixed gas is introduced from a combustion burner into a combustion flame formed in the reaction chamber. In addition, you may introduce | transduce the vapor | steam concerning silicon, the vapor | steam concerning titanium, and the vapor | steam concerning aluminum separately as a late stage raw material in a reaction chamber.
(3) A particle containing silicon atoms, titanium atoms and aluminum atoms is generated by performing a combustion treatment at a temperature of 1,000 to 3,000 ° C. in the combustion flame.
(4) After the produced particles are cooled in a cooler, the gaseous reaction product is separated and removed in a separator. At this time, in some cases, hydrogen chloride adhering to the particle surface is removed in wet air. Further, deoxidation treatment of hydrogen chloride is performed in the processing chamber, and the composite particles are collected in a silo by being collected by a filter.
As initial introduction amounts, silicon tetrachloride vapor [A: 12% by mass], titanium tetrachloride vapor [B: 65% by mass] and aluminum chloride vapor [C: 23% by mass] together with inert gas in the reaction chamber. As a late introduction amount, silicon tetrachloride vapor [A: 20% by mass], titanium tetrachloride vapor [B: 57% by mass] and aluminum chloride vapor [C: 23% by mass] are inert gases. And a composite gas containing silicon atoms, titanium atoms, and aluminum atoms by burning a mixed gas in which hydrogen and air are mixed in a predetermined ratio at a combustion temperature of 2,000 ° C. for 0.3 seconds. After being cooled and collected by a filter.
The obtained composite particles were dechlorinated by heating at 500 ° C. for 1 hour in an oven in an air atmosphere, and 500 parts by mass of this was charged into a high-speed stirring mixer equipped with a jacket for heating and stirring at 500 rpm. Then, 25 parts by mass of pure water was sprayed and supplied in a sealed state, and further stirred for 10 minutes. Subsequently, 25 parts by mass of hexamethyldisilazane was added, and the mixture was stirred for 60 minutes in a sealed state, and then aerated with nitrogen at 150 ° C. with stirring to remove the generated ammonia gas and the remaining treatment agent. Composite particles 6 were obtained.

<Preparation of toner base particles>
-Preparation of amorphous polyester resin dispersion-
15 mol parts of polyoxyethylene (2,0) -2,2-bis (4-hydroxyphenyl) propane and 85 mol parts of polyoxypropylene (2,2) -2,2-bis (4-hydroxyphenyl) propane 10 mole parts of terephthalic acid, 67 mole parts of fumaric acid, 3 mole parts of n-dodecenyl succinic acid, 20 mole parts of trimellitic acid, and 0.0025 parts by weight of dibutyl with respect to 100 parts by weight of these monomer components Tin oxide was added, nitrogen gas was introduced into the container and the temperature was raised in an inert atmosphere, and then a copolycondensation reaction was carried out at 150 to 230 ° C. for 12 to 20 hours. Thereafter, the pressure was gradually reduced at 210 ° C. to 250 ° C. to synthesize an amorphous polyester resin. The weight average molecular weight Mw of this resin was 65,000. Next, 3,000 parts of the obtained amorphous polyester resin, 10,000 parts of ion-exchanged water, and surfactant dodecylbenzenesulfonic acid were added to an emulsification tank of a high-temperature and high-pressure emulsifier (Cabitron CD1010, slit: 0.4 mm). After adding 90 parts of sodium, it is heated and melted to 130 ° C., and then dispersed at 110 ° C. at a flow rate of 3 L / m for 30 minutes at 10,000 rpm, and passed through a cooling tank to pass through an amorphous resin particle dispersion (high-temperature A high-pressure emulsifier (Cabitron CD1010, slit 0.4 mm) was recovered to obtain an amorphous resin particle dispersion.

-Preparation of Amorphous Polyester Resin Particle Dispersions 2-5-
Amorphous resin particle dispersions 2 to 5 were obtained in the same manner as amorphous polyester resin particle dispersion 1, except that the amount of dibutyltin oxide used as the catalyst was changed as shown in Table 2.

-Preparation of colorant dispersion-
-Cyan pigment (copper phthalocyanine B15: 3: manufactured by Dainichi Seika Kogyo Co., Ltd.): 1,000 parts by mass-Ionic surfactant Neogen RK (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.): 150 parts by mass-Ion exchange Water: 4,000 parts by mass The above compounded solution is mixed and dissolved, and dispersed with a high-pressure impact disperser Ultimateizer (HJP30006, manufactured by Sugino Machine Co., Ltd.) for 1 hour, and is colored with a volume average particle size of 180 nm and a solid content of 20%. An agent dispersion was obtained.

-Preparation of release agent dispersion-
Paraffin wax HNP9 (melting point 75 ° C .: Nippon Seiki Co., Ltd.): 46 parts by mass Cationic surfactant Neogen RK (Daiichi Kogyo Seiyaku Co., Ltd.): 5 parts by mass Ion exchange water: 200 parts by mass The above is heated to 100 ° C. and sufficiently dispersed with IKA Ultra Tarrax T50, then dispersed with a pressure discharge type gorin homogenizer, and a release agent dispersion having a center diameter of 200 nm and a solid content of 20.0% by mass. Got.

-Production of toner base particles 1-
-Noncrystalline resin particle dispersion 1: 256.8 parts by mass-Colorant dispersion: 27.4 parts by mass-Release agent dispersion: 35 parts by mass Thoroughly mixed and dispersed. Subsequently, 0.20 part by mass of polyaluminum chloride was added thereto, and the dispersion operation was continued with an ultra turrax. The flask was heated to 48 ° C. with stirring in an oil bath for heating. After maintaining at 48 ° C. for 60 minutes, 70.0 parts by mass of the amorphous resin dispersion 1 was gradually added thereto. Thereafter, the pH of the system was adjusted to 8.0 with a 0.5 mol / L sodium hydroxide aqueous solution, and then the stainless steel flask was sealed and heated to 96 ° C. while continuing to stir using a magnetic seal for 3 hours. Retained. After completion of the reaction, the mixture was cooled, filtered, sufficiently washed with ion exchange water, and then subjected to solid-liquid separation by Nutsche suction filtration. This was further redispersed in 1 L of ion exchange water at 30 ° C., and stirred and washed at 300 rpm for 15 minutes. This was repeated five more times, and when the pH of the filtrate became 7.5 and the electric conductivity was 7.0 μS / cmt, solid-liquid separation was performed using No5A filter paper by Nutsche suction filtration. Vacuum drying was then continued for 12 hours. The particle diameter at this time was measured by Coulter Multisizer II (manufactured by Beckman Coulter, Inc.), and the volume average particle diameter was 5.8 μm. In addition, the particle shape factor SF1 obtained by shape observation with Luzex was 129.

-Production of toner base particles 2-5-
Toner base particles 2 to 5 were produced in the same manner as toner base particles 1 except that the amorphous resin particle dispersion 1 was changed to amorphous resin particle dispersions 2 to 5, respectively.

-Preparation of Styrene-Acrylic Resin Particle Dispersion (1)-
-Styrene 308 parts by mass-n-butyl acrylate 100 parts by mass-Acrylic acid 4 parts by mass-Dodecanethiol 8 parts by mass-Propanediol acrylate 1.5 parts by mass-Stannous octylate 0.5 parts by mass The above ingredients are mixed Dissolve, on the other hand, 4 parts by weight of the anionic surfactant Dowfax (manufactured by Dow Chemical Co., Ltd.) dissolved in 550 parts by weight of ion-exchanged water is placed in a flask and dispersed by adding the above mixed solution. After emulsifying and slowly stirring and mixing for 10 minutes, 50 parts by mass of an ion exchange aqueous solution in which 6 parts by mass of ammonium persulfate was dissolved was added.
Next, after sufficiently replacing the inside of the system with nitrogen, the flask was heated with an oil bath to 75 ° C. while stirring to carry out emulsion polymerization.
As a result, a styrene-acrylic resin particle dispersion (1) (solid content concentration: 42%) having a central particle diameter (volume average particle diameter) of 180 nm, a glass transition temperature of 54 ° C., and a weight average molecular weight Mw of 25,000 is obtained. It was. Further, the styrene-acrylic resin particle dispersion (1) was flushed into a vessel at 90 ° C. and 10 mmHg to distill off the solvent and the like, and then coarsely pulverized using a coarse pulverizer and styrene-acrylic having a 1 mm chip. Resin (1) was obtained.

-Preparation of toner base particles 6-
・ Styrene-acrylic resin (1): 26 parts ・ Hexahedral magnetite (manufactured by Toda Kogyo Co., Ltd .: MTH009F, particle size 0.2 μm): 50 parts ・ Negative charge control agent (Fe-containing azo dye): 1 part Low molecular weight polypropylene (softening point 149 ° C.): 2 parts Low molecular weight polyethylene (softening point 120 ° C.): 1 part A material having the above composition is mixed with a Henschel mixer, and this is set at a set temperature of 140 ° C. and a screw speed of 200 rpm. Heat kneaded with an extruder. The outlet temperature at this time was 190 degreeC. The kneaded product was cooled and coarsely pulverized to obtain a pulverized product having a volume average diameter of 6.9 μm. Further, the toner obtained by classifying the pulverized product was measured with Coulter Multisizer II (manufactured by Beckman Coulter, Inc.), and the volume average particle diameter was 6.5 μm. Further, the particle shape factor SF1 obtained from the shape observation by Luzex was 155.

<Production of toner>
According to Table 3, toner base particles and composite particles as external additives were mixed with a Henschel mixer at 3,600 rpm for 10 minutes to obtain a toner.
Regarding the external additive coverage of the obtained toner, the surface of the toner particle was observed after observing 100 fields of the toner particle surface at a magnification of 10,000 using a scanning electron microscope S4700 (manufactured by Hitachi, Ltd.). Is obtained by calculating the area of the toner surface where the external additive is attached using the area analysis tool of image processing analysis software WinROOF (manufactured by Mitani Shoji Co., Ltd.). Was 54%.

<Creation of carrier>
Ferrite particles (average particle size 50 μm, volume electric resistance 3 × 10 8 Ω · cm): 100 parts by mass Toluene: 14 parts by mass Perfluorooctylethyl acrylate / dimethylaminoethyl methacrylate copolymer (copolymerization ratio 90:10, Mw = 50,000): 1.6 parts by mass Carbon black (VXC-72; manufactured by Cabot Corporation): 0.12 parts by mass The above components except for the ferrite particles are dispersed with a stirrer for 10 minutes to form a film. Prepare the solution, put the coating solution and ferrite particles in a vacuum degassing kneader, stir at 60 ° C. for 30 minutes, and then reduce the pressure by distilling off the toluene to form a resin coating on the ferrite particle surface. The carrier was manufactured.

<Production of developer>
The obtained toner of each example and the above-described carrier were each placed in a V blender at a mass ratio of 5:95 and stirred for 20 minutes to obtain a developer.

  The obtained developer was filled in Docu Center Color 400 (Fuji Xerox Co., Ltd.), and the following evaluation was performed.

<Evaluation>
The developer obtained in an environment room at a room temperature of 32 ° C. and a humidity of 80% is used as a modified DocuCenter Color 400 machine manufactured by Fuji Xerox Co., Ltd. (image carrier, charging unit, exposure unit, development unit, transfer unit, and fixing unit). The charging means is a means using a charging roller that applies a voltage to a semiconductive rubber roller to cause discharge in the vicinity of the contact portion with the photosensitive member to charge the photosensitive member. 10,000 continuous prints were made. The amount of light for development was adjusted so that the toner was developed in the form of a patch on the photoreceptor by the development process, and the amount of toner per area was 2.7 (g / m ² ). This light quantity adjustment work was performed every time the developer was changed and evaluated.

-Fogging-
The white portion (portion where there is no toner patch) on the photoconductor was transferred to a tape and measured with a density measuring device X-rite 404A manufactured by X-rite. The evaluation value was D = (measured value) − (value of the tape only), and the evaluation was performed according to the following criteria.
A: D ≦ 0.01
B: 0.01 <D ≦ 0.02
C: 0.02 <D <0.10
D: 0.10 ≦ D

-Transfer efficiency-
Transfer the toner patch from the photoconductor to the intermediate transfer belt, then remove the photoconductor that has not been cleaned, and remove the toner that has not been transferred by applying a transparent tape to the position of the toner patch on the photoconductor and peeling it off. It was collected. The collected toner was affixed to the white plate together with the tape, and the transferability was visually evaluated by observing the coloring with the toner that was not transferred.
The evaluation criteria are as follows.
A: Coloring with toner cannot be visually confirmed on the white plate.
B: Coloring with toner can be visually confirmed, which is a practical problem.

Claims (9)

Toner base particles, and
Containing an external additive externally added to the toner base particles,
The external additive contains particles containing silica and titania,
The abundance ratio of titanium atoms to silicon atoms on the outermost surface of the toner is 0.1 to 5 atm%,
A toner for developing an electrostatic charge image, wherein the content of tin atoms in the whole toner is 0.001 to 1% by mass.   The toner for developing an electrostatic charge image according to claim 1, wherein an abundance ratio of titanium atoms to silicon atoms on the outermost surface of the toner is 1 to 5 atm%.   The electrostatic image developing toner according to claim 1, wherein the toner base particles contain polyester as a binder resin.   An electrostatic charge image developer comprising the electrostatic charge image developing toner according to claim 1 and a carrier.   A toner cartridge containing the electrostatic image developing toner according to claim 1.   A developer cartridge containing the electrostatic charge image developer according to claim 4.   5. A process cartridge comprising a developer holder that contains the electrostatic charge image developer according to claim 4 and holds and conveys the electrostatic charge image developer. A latent image forming step for forming an electrostatic latent image on the surface of the image carrier;
A developing step of forming a toner image by developing the electrostatic latent image formed on the surface of the image carrier with a developer containing toner;
A transfer step of transferring the toner image onto the surface of the transfer target; and
A fixing step of fixing the toner image transferred to the surface of the transfer target,
An image forming method using the electrostatic image developing toner according to claim 1 or the electrostatic image developer according to claim 4 as the developer. Image carrier,
Charging means for charging the image carrier;
Exposure means for exposing the charged image carrier to form an electrostatic latent image on the surface of the image carrier;
Developing means for developing the electrostatic latent image with a developer containing toner to form a toner image;
Transfer means for transferring the toner image from the image carrier to the surface of the transfer target; and
Fixing means for fixing the toner image transferred to the surface of the transfer object,
An image forming apparatus comprising the electrostatic image developing toner according to claim 1 or the electrostatic charge image developer according to claim 4 as the developer.