JP7216604B2 - toner - Google Patents

Description

The present invention relates to electrophotography, an imaging method for visualizing electrostatic charge images, and a method for producing toners used in toner jets.

As copiers and printers become more widespread, the performance required for toners is becoming more advanced. In recent years, a digital printing technique called print on demand (POD), in which printing is performed directly without a plate making process, has attracted attention. Considering the application of the image forming method using toner to the POD market, even when high-speed and large-volume output is performed for a long period of time, it is possible to stably produce prints with higher image quality than before. required to obtain.

Therefore, many proposals have been made so far to add large-diameter particles capable of imparting a spacer effect to the toner for the purpose of maintaining stable fluidity over a long period of time. Japanese Patent Application Laid-Open No. 2002-100001 proposes to maintain the fluidity of the toner by adding large-diameter silica particles formed by a sol-gel method to the toner particles.
In addition, the external additive migrates from the surface of the toner particles to the carrier or the like with long-term use, and may cause changes in charging performance and fluidity. In order to prevent this phenomenon, Japanese Patent Application Laid-Open No. 2002-100002 proposes a method of heat-treating the toner to fix large-diameter silica particles as an external additive to the toner particles.

However, when considering further environmental changes and higher quality than before, toner using large-sized silica particles, which can give a spacer effect to the toner, may cause uneven charge distribution after long-term use. It's easy and there's room for improvement. Specifically, the surface layer of one toner is in a state where the toner composition is mixed, and since charging performance and electrical resistance differ depending on the raw material, there are sparsely charged portions and low charged portions. In particular, silica particles and the like have high electrical resistance and are considered to be strongly charged. As a result, when the toner is used for a long period of time, the silica particles tend to be biased in charge. As a result, the charge distribution in the surface layer of each toner layer tends to become more uneven, and when considering higher quality than in the past, the toner image is slightly disturbed with respect to the latent image, resulting in insufficient dot reproducibility. becomes. In addition, due to the non-uniform charge distribution on the surface layer of one toner, the phenomenon of fixing explosion, in which the toner image on the image is disturbed by the influence of the fixing member during fixing, and the phenomenon of electrostatic offset, in which the fixing member is offset, tend to occur. .

On the other hand, Patent Document 2 discloses strontium titanate-based fine particles as a toner external additive having good environmental properties and charging properties.
However, although the toner or the external additive for toner described in Patent Document 2 improves the charge uniformity of the entire toner to be developed, the charge uniformity of the surface layer of one toner is not discussed. Also, long-term use such as in the POD market has not been discussed, and there is room for improvement in order to achieve the image quality required in the recent POD market.
The present invention has been made in view of the above problems. In other words, even in cases where higher image quality is required over a long period of time, such as in the POD market, the surface layer of each toner has excellent charge uniformity, dot reproducibility, suppression of fixing explosion, and suppression of electrostatic offset. An object of the present invention is to provide a toner having good

JP 2012-163623 A JP 2015-137208 A

An object of the present invention is to provide a toner that is excellent in dot reproducibility, suppression of fixing explosion, and suppression of electrostatic offset even when high-speed and large-volume output is performed over a long period of time, and that can achieve higher image quality than conventional toners. is to provide

The inventors of the present invention have found that by controlling the states of existence of strontium titanate and large-diameter silica in the toner after water washing, it is possible to improve the charge uniformity in the surface layer of one toner even in long-term use. Found it. As a result, it is possible to obtain a toner that is excellent in dot reproducibility, suppression of fixing explosion, and suppression of electrostatic offset even when high-speed and large-volume output is performed for a long period of time, and that can achieve higher image quality than conventional toners. I found out.
That is, the toner of the present invention is a toner having toner particles and inorganic fine particles A and silica fine particles B present on the surfaces of the toner particles,
The inorganic fine particles A have a dielectric constant of 35 pF/m or more and 100 pF/m or less in a dielectric constant measurement at a temperature of 25° C. and a frequency of 1 MHz,
Regarding the washed toner obtained by washing the toner,
The content Z of the inorganic fine particles A in the washed toner is 0.2% by mass or more and 10.0% by mass or less with respect to the mass of the washed toner,
The silica fine particles B present in the washed toner have a primary particle number average particle diameter (D1) DB of 60 nm or more and 300 nm or less,
When the coverage of the inorganic fine particles A in the washed toner measured by an X-ray photoelectron spectrometer (ESCA) is X, and the coverage of the silica fine particles B is Y,
0.10≤X/Y≤5.00.

According to the present invention, a toner that is excellent in dot reproducibility, suppression of fixing explosion, and suppression of electrostatic offset even when high-speed and large-volume output is performed over a long period of time, and that can achieve higher image quality than conventional toners. can be provided.

1 is a schematic diagram of a toner surface treatment apparatus used in the present invention; FIG.

In the present invention, unless otherwise specified, the descriptions of "○○ or more and XX or less" and "○○ to XX", which represent numerical ranges, mean numerical ranges including the lower and upper limits that are endpoints.
The toner of the present invention is a toner having toner particles and inorganic fine particles A and silica fine particles B present on the surfaces of the toner particles,
The inorganic fine particles A have a dielectric constant of 35 pF/m or more and 100 pF/m or less in a dielectric constant measurement at a temperature of 25° C. and a frequency of 1 MHz,
Regarding the washed toner obtained by washing the toner,
The content Z of the inorganic fine particles A in the washed toner is 0.2% by mass or more and 10.0% by mass or less with respect to the mass of the washed toner,
The silica fine particles B present in the washed toner have a primary particle number average particle diameter (D1) DB of 60 nm or more and 300 nm or less,
When X is the coverage of the inorganic fine particles A and Y is the coverage of the silica fine particles B in the washed toner measured by an X-ray photoelectron spectrometer (ESCA),
0.10≤X/Y≤5.00
is.
Incidentally, the expression "existing on the surface of the toner particles" includes both states in which the inorganic fine particles A and the silica fine particles B adhere to and adhere to the surfaces of the toner particles.

The reason why the above structure can obtain an excellent effect that has not existed in the past is considered as follows.
The inorganic fine particles A contained in the toner of the present invention have a dielectric constant of 35 pF/m or more and 100 pF/m or less as measured at a temperature of 25° C. and a frequency of 1 MHz. Further, it is preferably 50 pF/m or more and 90 pF/m or less, more preferably 60 pF/m or more and 80 pF/m or less.

The fact that the dielectric constant of the inorganic fine particles A is within the above range indicates that the inorganic fine particles A are easily polarized. Therefore, the inorganic fine particles A can attract and relax the charge of the highly charged portion existing in the surroundings.
When the dielectric constant is 35 pF/m or more, the inorganic fine particles A are easily polarized, and the toner rubs against each other, thereby effectively attracting the charge of highly charged portions existing in the surroundings. Further, when the dielectric constant is 100 pF/m or less, the polarization of the inorganic fine particles A does not become too large, and the electric charges of highly charged portions present in the surroundings are not excessively attracted.

As a result, the toner rubs against each other, so that the inorganic fine particles A adhered to the surface layer of the toner particles effectively attract and relax the charge of the highly charged portion present in the surroundings. Therefore, by repeated contact of the toner particles in a developing device, etc., the charge of the highly charged portion existing on the toner particle surface layer is attracted to the adjacent inorganic fine particles A on the surface layer of the toner particles and spreads uniformly. As a result, the charge uniformity in the surface layer of one toner particle is improved. As a result, dot reproducibility, suppression of fixing explosion, and suppression of electrostatic offset are improved.

Further, the content Z of the inorganic fine particles A in the washed toner is 0.2% by mass or more and 10.0% by mass or less with respect to the mass of the washed toner. Moreover, it is preferably 2.2% by mass or more and 9.9% by mass or less, and more preferably 3.6% by mass or more and 8.0% by mass or less.
The washed toner, which is obtained by washing the toner according to the present invention, simulates the state of the toner after external additives are removed from the toner surface due to stress received in a developing device or the like due to long-term use. ing. Therefore, in order to evaluate the electrophotographic properties, it is important to clarify the state of the toner after washing with water.
The fact that the content Z of the inorganic fine particles A in the toner after water washing is within the above range means that the inorganic fine particles A are appropriately present in the vicinity of the toner particle surfaces even when the toner is used for a long period of time. represent. As a result, when the toner is used for a long period of time, due to the friction between the toner particles, the electric charges of the highly charged portions existing on the surface layer of the toner are attracted to the inorganic fine particles A in the vicinity of the neighboring toner particle surfaces, and are evenly distributed. spread. As a result, the charging uniformity in the surface layer of each toner is improved.

When the content Z is 0.2% by mass or more, there is a sufficient chance of contact with highly charged portions existing in the surroundings when the toner is used for a long period of time. Further, when the content Z is 10.0% by mass or less, when the toner is used for a long period of time, the chances of contact with highly charged portions existing in the surroundings do not increase too much, and excessive charge is not attracted. Therefore, the charge amount of the toner as a whole does not decrease too much. As a result, the charge uniformity in the surface layer of one toner particle is improved, and dot reproducibility, suppression of fixing explosion, and suppression of electrostatic offset are improved.

Further, it is preferable that the inorganic fine particles A are strongly fixed to the surface of the toner particles so that they can stably exist on the surface of the toner particles even after long-term use. As a method for strongly fixing the toner particles and the inorganic fine particles A, hot air treatment or mechanical impact treatment may be applied during or after mixing. Among these, hot air treatment is particularly preferred. By applying the hot air treatment, the inorganic fine particles A can be firmly thermally adhered to the toner particle surfaces.

Further, the number average particle diameter (D1) DB of the primary particles of the silica fine particles B present in the toner after washing with water is 60 nm or more and 300 nm or less. Moreover, it is preferably 70 nm or more and 280 nm or less.

The fact that silica fine particles with a large particle size are present on the surface of the toner after being washed with water means that silica fine particles with a large particle size are fixed to the surface of the toner particles even after long-term use. are doing. Therefore, the toner of the present invention can exhibit a high spacer effect and charge retention property over a long period of time due to the silica fine particles having a large particle size.

When the number average particle diameter (D1) DB is 60 nm or more, even when used for a long period of time, it is possible to exhibit a high spacer effect and charge maintenance property over a long period of time without being buried in the toner particles. Further, when the number average particle diameter (D1) DB is 300 nm or less, even when used for a long period of time, silica fine particles having a large particle diameter are separated from the toner particles by the carrier and the developer due to the mechanical load in the developing device. Does not migrate to internal components. Therefore, even when the toner is used for a long period of time, it is possible to exhibit a high spacer effect and charge retention over a long period of time. As a result, dot reproducibility, suppression of fixing explosion, and suppression of electrostatic offset are improved.

Further, in order to allow the silica fine particles B to exist in the toner after being washed with water, it is preferable that the silica fine particles B are partially embedded in the resin on the surface of the toner particles. As a method of embedding, hot air treatment or mechanical impact treatment may be applied during or after the toner particles and silica fine particles B are mixed. Among these, hot air treatment is particularly preferred. By applying the hot air treatment, the silica fine particles B can be firmly thermally adhered to the toner particle surfaces.

Further, the toner of the present invention has a coverage of 0.10 where X is the coverage of the inorganic fine particles A and Y is the coverage of the silica fine particles B in the washed toner measured by an X-ray photoelectron spectrometer (ESCA). ≤X/Y≤5.00. It is also preferably 0.15≦X/Y≦1.50, more preferably 0.20≦X/Y≦1.00. This indicates that a certain amount of inorganic fine particles A exists relative to silica fine particles in the surface layer of the toner particles after long-term use.

Since a certain amount of the inorganic fine particles A having a dielectric constant within the above range is present relative to the silica fine particles B, the inorganic fine particles A adhered to the surface layer of the toner particles are polarized, and the charge of the silica fine particles B can be sufficiently attracted. . As a result, when the toner is used for a long period of time, the charge of the silica fine particles B present on the toner particle surface layer is attracted to the adjacent inorganic fine particles A on the toner particle surface layer due to the friction between the toner particles, and spreads evenly. . As a result, the charging uniformity in the surface layer of one toner particle is improved.

Due to the above effects, even when high-speed and large-volume output is performed over a long period of time, the toner is excellent in dot reproducibility, suppression of fixing explosion, and suppression of electrostatic offset, and achieves higher image quality than conventional toners. The configuration that can be provided to achieve the object of the present invention will be described in detail below.

[Inorganic fine particles A]
The toner in the present invention has inorganic fine particles A on the surface of the toner particles. In the present invention, the inorganic fine particles A preferably have a cubic or rectangular parallelepiped shape. A cubic shape or a rectangular parallelepiped shape is preferable for exhibiting the effect of the present invention because it can firmly adhere to the toner particle surface layer.
Further, the number average particle diameter (D1) DA of the primary particles of the inorganic fine particles A contained in the washed toner of the present invention is preferably 10 nm or more and 95 nm or less. It is more preferably 20 nm or more and 80 nm or less, and still more preferably 25 nm or more and 70 nm or less. When the number average particle diameter (D1) DA of the primary particles of the inorganic fine particles A is within the above range, the surfaces of the toner particles can be efficiently covered. Therefore, when the toner is used for a long period of time, the inorganic fine particles A and the silica fine particles B on the surface layer of the toner particles are brought into contact with each other efficiently by rubbing against each other. As a result, the charges of the silica fine particles B present on the toner particle surface layer are efficiently attracted to the adjacent inorganic fine particles A on the toner particle surface layer and uniformly spread, thereby further improving the charge uniformity on the surface layer of one toner particle. As a result, dot reproducibility, suppression of fixing explosion, and suppression of electrostatic offset are improved.

The number average particle diameter (D1) DA of the primary particles of the inorganic fine particles A and the number average particle diameter (D1) DB of the primary particles of the silica fine particles B preferably satisfy the following relationship.
DA<DB
By satisfying the above relationship, the inorganic fine particles A and the silica fine particles B on the surface layer of the toner particles can be in contact with each other more efficiently. As a result, the charge of the silica fine particles B present on the adjacent toner particle surface layer is efficiently attracted by the inorganic fine particle A on the adjacent toner particle surface layer and spreads evenly, thereby further improving the charging uniformity of the toner particle surface layer. do. As a result, dot reproducibility, suppression of fixing explosion, and suppression of electrostatic offset are improved.

Furthermore, the surface of the inorganic fine particles A is preferably treated with a fluorine-based silane coupling agent.
Examples of fluorine-based silane coupling agents include trifluoropropyltrimethoxysilane and perfluorooctylethyltriethoxysilane.
Further, the amount of surface treatment with the fluorine-based silane coupling agent is preferably 1 part by mass to 60 parts by mass, more preferably 2 parts by mass to 20 parts by mass, with respect to 100 parts by mass of the inorganic fine particles. It is preferably from 3 parts by mass to 10 parts by mass.

Since the surfaces of the inorganic fine particles A are treated with a fluorine-based silane coupling agent, the charge amount of the inorganic fine particles A can be maintained at a moderately high level, and the charging performance of the toner is improved, resulting in better dot reproducibility. , the suppression of fixing explosion and the suppression of electrostatic offset are improved.
Further, the surfaces of the inorganic fine particles A may be surface-treated with other treatment agents in addition to the surface treatment with the fluorine-based silane coupling agent, if necessary. Alkylalkoxysilane is preferred as the treatment agent. Also, the alkylalkoxysilane is preferably an alkylalkoxysilane represented by the following formula (1).
m in the following formula (1) represents a natural number of 1 to 3, and n represents a natural number of 4 to 18.

Examples of the alkylalkoxysilane include the following. isobutyltrimethoxysilane, isobutyltriethoxysilane, pentyltrimethoxysilane, pentyltriethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, decyltrimethoxysilane, decyl triethoxysilane, dodecyltrimethoxysilane, dodecyltriethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, octadecyltrimethoxysilane, octadecyltriethoxysilane, and the like.

Further, the amount of surface treatment with the alkylalkoxysilane is preferably 1 part by mass to 60 parts by mass, more preferably 2 parts by mass to 20 parts by mass, and 3 parts by mass with respect to 100 parts by mass of the inorganic fine particles A. Parts to 10 parts by mass are more preferable.
Further, preferably, the surfaces of the inorganic fine particles A are surface-treated with both the fluorine-based silane coupling agent and the alkylalkoxysilane represented by the formula (1).

By surface-treating both, the charge uniformity in one toner surface layer is further improved. Although the reason for this is not clear, it is speculated as follows.
By treating with a fluorine-based silane coupling agent, the charge amount of the inorganic fine particles A can be maintained at a moderately high level, and the charging performance of the toner is improved. On the other hand, alkylalkoxysilanes are compatible with binder resins such as polyester resins and styrene-acrylic resins. Therefore, the charges of the inorganic fine particles A that have attracted the charges of the silica fine particles B through the alkylalkoxysilane easily spread evenly to the binder resin portion forming the surface layer of the toner particles. As a result, each of the inorganic fine particles A, the silica fine particles B, and the binder resin portion constituting the surface layer of the toner particles, which are present on the surface layer of the toner particles, becomes more uniformly charged, and the charge uniformity of the surface layer of one toner particle is further improved. As a result, dot reproducibility, suppression of fixing explosion, and suppression of electrostatic offset are improved.

The surface treatment of the inorganic fine particles A is not particularly limited as long as it is a generally known treatment.
For example, the following methods may be used.
A method of dispersing the inorganic fine particles in a solution of a surface treatment agent dissolved in an organic solvent, removing the solvent by filtration or a spray drying method, and then curing by heating;
A dry treatment method such as a method in which a solution of a surface treatment agent dissolved in an organic solvent is spray-coated onto the inorganic fine particles using a fluidized bed apparatus, followed by heat drying to remove the solvent and cure the film;
A wet treatment method in which the inorganic fine particles are surface treated with a surface treatment agent in an aqueous medium, neutralized with an alkali, filtered, washed, dried and pulverized.

The structure of the inorganic fine particles A is preferably a perovskite crystal structure.
The perovskite crystal structure allows the inorganic fine particles A to be polarized more effectively. As a result, when the toner is used for a long period of time, the toner rubs against each other, and the inorganic fine particles A adhering to the surface layer of the toner particles effectively attract and relieve the charge of the silica fine particles B. Therefore, when the toner is used for a long period of time, the charge of the silica fine particles B existing on the toner particle surface layer is attracted to the adjacent inorganic fine particles A on the toner particle surface layer due to the friction between the toner particles, and spreads evenly. As a result, the charge uniformity in the surface layer of one toner particle is improved, and dot reproducibility, suppression of fixing explosion, and suppression of electrostatic offset are improved.

In order to confirm that the structure is a perovskite crystal structure (a face-centered cubic lattice composed of three different elements), X-ray diffraction measurement should be performed.
Examples of inorganic fine particles having a perovskite crystal structure include calcium titanate particles, strontium titanate particles, calcium zirconate particles, and strontium zirconate particles. Among these, strontium titanate particles are more preferable. Strontium titanate can be polarized more effectively, and can more effectively trap the charge of the silica fine particles B when the toner rubs against each other due to circulation in the device during long-term use. Therefore, the charge of the silica fine particles B spreads more uniformly on the surface layer of one toner particle, so that dot reproducibility, suppression of fixing explosion, and suppression of electrostatic offset are improved.

The method for producing strontium titanate is not particularly limited, and the following methods can be exemplified.
As a titanium oxide source, a hydrolyzate of a titanium compound, which is peptized with mineral acid, can be used. Preferably, metatitanic acid having an SO ₃ content of 1.0% by mass or less, preferably 0.5% by mass or less obtained by the sulfuric acid method is dissolved by adjusting the pH to 0.8 to 1.5 with hydrochloric acid. Glue should be used.

Metal nitrates, hydrochlorides and the like can be used as metal oxide sources, and for example, strontium nitrate and strontium chloride can be used.
As the alkaline aqueous solution, caustic alkali can be used, and sodium hydroxide aqueous solution is particularly preferable.
In the production of strontium titanate, factors affecting the particle size include the following. pH when peptizing metatitanic acid with hydrochloric acid, mixing ratio of titanium oxide source and metal source other than titanium, titanium oxide source concentration at the initial stage of reaction, temperature when adding alkaline aqueous solution, addition rate, reaction time and stirring conditions. Such. In particular, if the reaction is stopped by rapidly lowering the temperature of the system by immersing it in ice water after the addition of the alkaline aqueous solution, the reaction can be forcibly stopped in the middle of crystal growth saturation, resulting in a wide particle size distribution. Easy to get. A wide particle size distribution can also be obtained by making the state of the reaction system nonuniform by, for example, reducing the stirring speed or changing the stirring method.

These factors can be appropriately adjusted in order to obtain metal titanate particles having the desired particle size and particle size distribution. In order to prevent the formation of carbonate during the reaction process, it is preferable to prevent contamination with carbon dioxide by, for example, conducting the reaction in a nitrogen gas atmosphere.
Further, in the production of strontium titanate, factors that affect the dielectric constant include conditions and operations that destroy grain crystallinity. For example, it is preferable to perform the operation of applying energy to disturb the crystal growth while increasing the concentration of the reaction solution. A specific method is to add nitrogen micro-bubbling to the crystal growth process.

The mixing ratio of the titanium oxide source and the metal source other than titanium during the reaction is 0 when the metal other than titanium is represented by M and the oxide is represented by M _X O, and the molar ratio of M _X O/TiO ₂ is 0. 0.90 or more and 1.40 or less, and more preferably 1.05 or more and 1.20 or less. However, X is 1 when M is an alkaline earth metal, and X is 2 when M is an alkali metal.

When the M _X O/TiO ₂ (molar ratio) is less than 0.90, not only metal titanate but also unreacted titanium oxide tends to remain as a reaction product. Metal sources other than titanium have relatively _high solubility in water, whereas _titanium oxide sources have low solubility in water. Not only the metal titanate but also the unreacted titanium oxide tend to remain.

The concentration of the titanium oxide source at the beginning of the reaction is preferably 0.050 mol/L or more and 1.300 mol/L or less, more preferably 0.080 mol/L or more and 1.200 mol/L or less as TiO ₂ . is more preferable.
By increasing the concentration of the titanium oxide source at the initial stage of the reaction, the number average particle diameter of the primary particles of the metal titanate particles can be reduced.

If the temperature for adding the alkaline aqueous solution is 100° C. or higher, a pressure vessel such as an autoclave is required, and practically a range of 60° C. or higher and 100° C. or lower is appropriate.
As for the addition rate of the alkaline aqueous solution, the slower the addition rate, the larger the metal titanate particles can be obtained, and the faster the addition rate, the smaller the metal titanate particles can be obtained. The addition rate of the alkaline aqueous solution is preferably 0.001 equivalents/h or more and 1.2 equivalents/h or less, more preferably 0.002 equivalents/h or more and 1.1 equivalents/h or less with respect to the charged raw material. . These can be appropriately adjusted according to the particle size to be obtained.

In the production method, it is preferable to further acid-treat the metal titanate particles obtained by the atmospheric pressure heating reaction. If the mixing ratio of the titanium oxide source and the metal source other than titanium exceeds 1.00 in terms of M _X O/TiO ₂ (molar ratio) when the metal titanate particles are produced by heating under normal pressure, Unreacted metal sources other than titanium that remain after the completion of the reaction react with carbon dioxide gas in the air. As a result, impurities such as metal carbonates are likely to be generated. In addition, if impurities such as metal carbonates remain on the surface, it becomes difficult to evenly coat the surface with a surface treatment agent during surface treatment for imparting hydrophobicity due to the influence of the impurities. Therefore, after the addition of the alkaline aqueous solution, acid treatment should be performed to remove the unreacted metal source.

In the acid treatment, it is preferable to adjust the pH to 2.5 or more and 7.0 or less using hydrochloric acid, and it is more preferable to adjust the pH to 4.5 or more and 6.0 or less.
As an acid, besides hydrochloric acid, nitric acid, acetic acid, or the like can be used for the acid treatment. The use of sulfuric acid tends to generate metal sulfates with low water solubility.

The strontium titanate of the present invention can be surface-treated.
Although the surface treatment agent is not particularly limited, it may be a disilylamine compound, a halogenated silane compound, a silicone compound or a silane coupling agent.
A disilylamine compound is a compound having a disilylamine (Si—N—Si) moiety. Examples of disilylamine compounds include hexamethyldisilazane (HMDS), N-methyl-hexamethyldisilazane or hexamethyl-N-propyldisilazane. Examples of halogenated silane compounds include dimethyldichlorosilane.

Examples of silicone compounds include silicone oils or silicone resins (varnishes). Examples of silicone oils include dimethyl silicone oil, methylphenyl silicone oil, α-methylstyrene-modified silicone oil, chlorophenyl silicone oil and fluorine-modified silicone oil. Examples of silicone resins (varnishes) include methylsilicone varnishes and phenylmethylsilicone varnishes.

Examples of the silane coupling agent include a silane coupling agent having an alkyl group and an alkoxy group, a silane coupling agent having an amino group and an alkoxy group, or a fluorine-containing silane coupling agent. More specifically, the silane coupling agent includes dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, trimethylmethoxysilane, trimethyldiethoxysilane, triethylmethoxysilane, triethyldiethoxysilane, γ-glycerol. sidoxypropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyldimethoxymethylsilane or γ-aminopropyldiethoxymethylsilane, 3 , 3,3-trifluoropropyldimethoxysilane, 3,3,3-trifluoropropyldiethoxysilane, perfluorooctylethyltriethoxysilane, 1,1.1-trifluorohexyldiethoxysilane and the like.

[Silica fine particles B]
Silica fine particles B may be produced by a known production method such as a combustion method or hydrothermal synthesis, but amorphous silica particles produced by a combustion method are less susceptible to moisture in the air, which is preferable.
Furthermore, the silica particles preferably have their surfaces hydrophobized with a fatty acid or a metal salt thereof, silicone oil, a silane coupling agent, a titanium coupling agent, etc. Among them, hexamethyldisiloxane (HMDS), Silane coupling agents such as octyltriethoxysilane and dichlorosilane are more preferred.

Further, the content S of the silica fine particles B in the washed toner is preferably 0.10% by mass or 50% by mass or less with respect to the mass of the washed toner.
When the content S of the silica fine particles B is within the above range, even when the toner is used for a long period of time, it is possible to obtain a high spacer effect of the silica fine particles B and charge maintenance property more effectively. As a result, dot reproducibility, suppression of fixing explosion, and suppression of electrostatic offset are improved.

Further, it is preferable that the content Z of the inorganic fine particles A and the content S of the silica fine particles B in the toner after washing with water satisfy the following relationship.
Z>S

This indicates that a sufficient amount of inorganic fine particles A exists relative to the silica fine particles in the vicinity of the toner particle surface after long-term use. Since the inorganic fine particles A having a dielectric constant within the range described above are present in a sufficient amount relative to the silica fine particles B, when the toner is used for a long period of time, the inorganic fine particles A fixed to the toner particle surfaces are polarized, and silica The charge of the fine particles B can be attracted more effectively. Therefore, when the toner is used for a long period of time, due to the friction between the toner particles, the charge of the silica fine particles B present in the vicinity of the surface of the toner particles is attracted to the inorganic fine particles A in the vicinity of the surface of the adjacent toner particles, and is evenly distributed. spread. As a result, the charging uniformity in the surface layer of each toner is improved. As a result, dot reproducibility, suppression of fixing explosion, and suppression of electrostatic offset are improved.

<Binder resin>
For the toner particles of the present invention, the following polymers can be used as the binder resin. Homopolymers of styrene and substituted products thereof such as polystyrene, poly-p-chlorostyrene and polyvinyltoluene; styrene-p-chlorostyrene copolymers, styrene-vinyltoluene copolymers, styrene-vinylnaphthalene copolymers, styrene -Styrenic copolymers such as acrylic acid ester copolymers and styrene-methacrylic acid ester copolymers; Resin; polyvinyl chloride, phenolic resin, natural modified phenolic resin, natural resin modified maleic acid resin, acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, polyurethane, polyamide resin, furan resin, epoxy resin, xylene resin , polyethylene resin, polypropylene resin, and the like. Among them, it is preferable to use a polyester resin as a main component from the viewpoint of adhesion of external additives.

Monomers used in the polyester unit of the polyester resin include polyhydric alcohols (divalent or trivalent or higher alcohols), polyvalent carboxylic acids (divalent or trivalent or higher carboxylic acids), acid anhydrides thereof, or lower Alkyl esters are used.
As the polyhydric alcohol monomer used for the polyester unit of the polyester resin, the following polyhydric alcohol monomers can be used.

Examples of dihydric alcohol components include the following. Ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol , 2-ethyl-1,3-hexanediol, hydrogenated bisphenol A, also bisphenol represented by formula (A) and derivatives thereof;

(Wherein, R is an ethylene or propylene group, x and y are each an integer of 0 or more, and the average value of x + y is 0 or more and 10 or less.)
diols represented by formula (B);

Examples of trihydric or higher alcohol components include sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, and 1,2,4-butanetriol. , 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene mentioned. Among these, glycerol, trimethylolpropane, and pentaerythritol are preferably used. These dihydric alcohols and trihydric or higher alcohols can be used alone or in combination.

As the polycarboxylic acid monomer used for the polyester unit of the polyester resin, the following polycarboxylic acid monomers can be used.
Examples of divalent carboxylic acid components include maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, malonic acid, n-dodecenylsuccinic acid, isododecenylsuccinic acid, n-dodecylsuccinic acid, isododecylsuccinic acid, n-octenylsuccinic acid, n-octylsuccinic acid, isooctenylsuccinic acid, isooctylsuccinic acid, anhydrides of these acids and Lower alkyl esters of these are included. Among these, maleic acid, fumaric acid, isophthalic acid, terephthalic acid and n-dodecenylsuccinic acid are preferably used.

Trivalent or higher carboxylic acids, their acid anhydrides and their lower alkyl esters include, for example, 1,2,4-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid and 1,2,4-naphthalenetricarboxylic acid. , 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, 1,2,4-cyclohexanetricarboxylic acid, tetra( methylenecarboxyl)methane, 1,2,7,8-octanetetracarboxylic acid, pyromellitic acid, empol trimer acid, their acid anhydrides or their lower alkyl esters. Among these, 1,2,4-benzenetricarboxylic acid, ie, trimellitic acid or derivatives thereof, is particularly preferred because it is inexpensive and reaction control is easy. These bivalent carboxylic acids and trivalent or higher carboxylic acids can be used alone or in combination.

The method for producing the polyester unit of the present invention is not particularly limited, and known methods can be used. For example, the above alcohol monomer and carboxylic acid monomer are mixed at the same time, polymerized through an esterification reaction or a transesterification reaction, and a condensation reaction to produce a polyester resin. Moreover, the polymerization temperature is not particularly limited, but is preferably in the range of 180° C. or higher and 290° C. or lower. Polymerization catalysts such as titanium-based catalysts, tin-based catalysts, zinc acetate, antimony trioxide, and germanium dioxide can be used for the polymerization of the polyester units.

Further, the acid value of the polyester resin is 0.1 to 50 mgKOH/g, preferably 1 to 40 mgKOH/g, more preferably 1 to 30 mgKOH/g, and the hydroxyl value is 5 to 80 mgKOH/g, preferably 5 to 60 mgKOH. /g, more preferably in the range of 10 to 50 mgKOH/g, from the viewpoint of toner chargeability and appropriate mechanical strength.

Also, the binder resin may be a mixture of a low-molecular-weight resin and a high-molecular-weight resin. It is preferable that the content ratio of the high-molecular-weight resin and the low-molecular-weight resin is 40/60 or more and 85/15 or less on a mass basis in order to partially embed the inorganic fine particles A and the silica fine particles B in the resin on the surface of the toner particles. .

<Colorant>
The toner of the present invention can be used as a magnetic one-component developer, a non-magnetic one-component developer, or a non-magnetic two-component developer.
In the case of a magnetic one-component developer, a magnetic substance is preferably used as the coloring agent. The magnetic material includes magnetic iron oxides such as magnetite, maghemite, and ferrite, and magnetic iron oxides including other metal oxides; metals such as Fe, Co, and Ni, or these metals together with Al, Co; Alloys with metals such as Cu, Pb, Mg, Ni, Sn, Zn, Sb, Be, Bi, Cd, Ca, Mn, Se, Ti, W, V, and mixtures thereof.
The content of the magnetic material is preferably 30 parts by mass or more and 100 parts by mass or less with respect to 100 parts by mass of the binder resin.

In the case of the non-magnetic one-component developer and the non-magnetic two-component developer, the coloring agents include the following.
Examples of black pigments include carbon black such as furnace black, channel black, acetylene black, thermal black and lamp black. Magnetic materials such as magnetite and ferrite can also be used.

Examples of yellow coloring agents include the following pigments and dyes.
As a pigment, C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 17, 23, 62, 65, 73, 74, 81, 83, 93, 94, 95, 97, 98, 109, 110, 111, 117, 120, 127, 128, 129, 137, 138, 139, 147, 151, 154, 155, 167, 168, 173, 174, 176, 180, 181, 183, 191, C.I. I. Bat Yellow 1, 3, 20 are mentioned.
As a dye, C.I. I. Solvent Yellow 19, 44, 77, 79, 81, 82, 93, 98, 103, 104, 112, 162 and the like.
These can be used individually by 1 type or in combination of 2 or more types.

Examples of cyan coloring agents include the following pigments and dyes.
As a pigment, C.I. I. Pigment Blue 1, 7, 15, 15; 1, 15; 2, 15; 3, 15; 4, 16, 17, 60, 62, 66, C.I. I. bat blue 6, C.I. I. Acid Blue 45 is mentioned.
As a dye, C.I. I. solvent blue 25, 36, 60, 70, 93, 95;
These can be used individually by 1 type or in combination of 2 or more types.

Examples of magenta coloring agents include the following pigments and dyes.
As a pigment, C.I. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48, 48; 2, 48; 3, 48; 4, 49, 50, 51, 52, 53, 54, 55, 57, 57; 63,64,68,81,81;1,83,87,88,89,90,112,114,122,123,144,146,150,163,166,169,177,184,185,202, 206, 207, 209, 220, 221, 238, 254, C.I. I. Pigment Violet 19; C.I. I. Bat Red 1, 2, 10, 13, 15, 23, 29, 35.

As a dye, C.I. I. solvent red 1, 3, 8, 23, 24, 25, 27, 30, 49, 52, 58, 63, 81, 82, 83, 84, 100, 109, 111, 121, 122, C.I. I. disperse thread 9, C.I. I. solvent violet 8, 13, 14, 21, 27, C.I. I. Oil-soluble dyes such as Disperse Violet 1, C.I. I. Basic Red 1, 2, 9, 12, 13, 14, 15, 17, 18, 22, 23, 24, 27, 29, 32, 34, 35, 36, 37, 38, 39, 40, C.I. I. basic dyes such as Basic Violet 1, 3, 7, 10, 14, 15, 21, 25, 26, 27, 28;
These can be used individually by 1 type or in combination of 2 or more types.
The content of the colorant is preferably 0.1 parts by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the binder resin.

<Inorganic fine particles>
The toner in the present invention contains inorganic fine particles A and silica fine particles B described above. Further, if necessary, other inorganic fine particles such as aluminum oxide may be contained.
The inorganic fine particles are mixed with the toner particles as an external additive. The device used for mixing is not particularly limited, and known mixers such as Henschel mixer, Mechanohybrid (manufactured by Nippon Coke Industry Co., Ltd.), Super Mixer, Nobilta (manufactured by Hosokawa Micron Co., Ltd.) can be used. can be done.

The inorganic fine particles are preferably hydrophobized with a hydrophobizing agent such as a silane compound, silicone oil or a mixture thereof.
Examples of external additives include resin fine particles and inorganic fine particles that function as charge aids, conductivity imparting agents, fluidity imparting agents, anti-caking agents, release agents during fixing with hot rollers, lubricants, and abrasives. is mentioned. Lubricants include polyethylene fluoride fine particles, zinc stearate fine particles, and polyvinylidene fluoride fine particles. Examples of abrasives include cerium oxide fine particles, silicon carbide fine particles, and strontium titanate fine particles.
Among these, it is preferable to externally add silica fine particles to the toner particles.

The silica fine particles preferably have a specific surface area of 30 m 2 /g or more and 500 m 2 /g or less, more preferably 50 m 2 /g or more and 400 m 2 /g or less, as determined by the BET method using nitrogen adsorption. The content of the silica fine particles is preferably 0.01 parts by mass or more and 8.0 parts by mass or less, and is 0.10 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the toner particles. is more preferable.

The BET specific surface area of silica fine particles was measured using a specific surface area measuring device Autosorb 1 (manufactured by Yuasa Ionics), GEMINI 2360/2375 (manufactured by Micrometric), and Tristar 3000 (manufactured by Micrometric). can be calculated using the BET multipoint method.
If necessary, the fine silica particles may be treated with the following treating agents for the purpose of hydrophobization and triboelectrification control.
Unmodified silicone varnishes, various modified silicone varnishes, unmodified silicone oils, various modified silicone oils, silane coupling agents, silane compounds having functional groups, or other organosilicon compounds.

<Developer>
The toner of the present invention can be used as a one-component developer, but can also be used as a two-component developer by mixing with a magnetic carrier in order to suppress charge localization on the toner surface.
As the magnetic carrier, for example, the following can be used.
iron oxide; metal particles such as iron, lithium, calcium, magnesium, nickel, copper, zinc, cobalt, manganese, chromium, and rare earths, their alloy particles, their oxide particles; magnetic materials such as ferrite. A magnetic material-dispersed resin carrier (so-called resin carrier) containing a magnetic material and a binder resin that holds the magnetic material in a dispersed state.

When the toner is mixed with a magnetic carrier and used as a two-component developer, the mixing ratio of the magnetic carrier at that time should be 2% by mass or more and 15% by mass or less as the toner concentration in the two-component developer. is preferable, more preferably 4.0% by mass or more and 13.0% by mass or less.

<Toner manufacturing method>
The method for producing the toner is not particularly limited, but a pulverization method is preferable from the viewpoint of dispersing toner materials such as pigments.
The procedure for manufacturing toner by the pulverization method will be described below.
In the raw material mixing step, predetermined amounts of other components such as a binder resin, a release agent, a colorant, and, if necessary, a charge control agent are weighed and mixed as materials constituting the toner particles. Examples of the mixing device include a double-con mixer, a V-type mixer, a drum-type mixer, a super mixer, a Henschel mixer, a Nauta mixer, and a Mechanohybrid (manufactured by Nippon Coke Kogyo Co., Ltd.).

Next, the mixed materials are melt-kneaded to disperse the pigment and the like in the binder resin. In the melt-kneading process, a batch-type kneader such as a pressure kneader or a Banbury mixer, or a continuous kneader can be used, and single-screw or twin-screw extruders are the mainstream because of their superiority in continuous production. ing. For example, KTK type twin-screw extruder (manufactured by Kobe Steel, Ltd.), TEM type twin-screw extruder (manufactured by Toshiba Machine Co., Ltd.), PCM kneader (manufactured by Ikegai Co., Ltd.), twin-screw extruder (Kei・Kneader (manufactured by Busu Co., Ltd.), Kneadex (manufactured by Nippon Coke Industry Co., Ltd.), and the like. Furthermore, the resin composition obtained by melt-kneading may be rolled with two rolls or the like and cooled with water or the like in the cooling step.

The cooled resin composition is then pulverized to a desired particle size in a pulverization step. In the pulverization process, for example, after coarse pulverization with a pulverizer such as a crusher, hammer mill, or feather mill, further, for example, Kryptron System (manufactured by Kawasaki Heavy Industries, Ltd.), Super Rotor (manufactured by Nisshin Engineering Co., Ltd.) , Turbo Mill (manufactured by Turbo Kogyo Co., Ltd.) or fine pulverizer using an air jet method.

After that, if necessary, inertial classification Elbow Jet (manufactured by Nittetsu Mining Co., Ltd.), centrifugal classification Turboplex (manufactured by Hosokawa Micron Corporation), TSP Separator (manufactured by Hosokawa Micron Corporation), Faculty (Hosokawa Micron Corporation) (manufactured by Co., Ltd.) or a sieving machine.

In addition, if necessary, after pulverization, hybridization system (manufactured by Nara Machinery Co., Ltd.), mechano fusion system (manufactured by Hosokawa Micron Co., Ltd.), faculty (manufactured by Hosokawa Micron Co., Ltd.), Meteor Rainbow MR Type (Japan (manufactured by Pneumatic Kogyo Co., Ltd.), the surface treatment of the toner particles such as spheroidization treatment can also be performed.
In particular, in the present invention, it is preferable that the inorganic fine particles A and the silica fine particles B are simultaneously added to the toner particles obtained by the above production method, mixed using a known mixer such as a Henschel mixer, and then subjected to surface treatment with hot air. . By such surface treatment, the inorganic fine particles A and the silica fine particles B can be embedded in the surface of the toner particles and fixed by heat.

In the present invention, it is preferable to obtain a toner by performing surface treatment with hot air using, for example, the surface treatment apparatus shown in FIG. 1, and classifying as necessary. Here, the outline of the surface treatment method using the hot air will be described with reference to FIG. 1, but the present invention is not limited to this. FIG. 1 is a sectional view showing an example of a surface treatment apparatus used in the present invention.

The mixture supplied by the raw material fixed quantity supply means 1 is guided to the introduction pipe 3 installed on the vertical line of the raw material supply means by the compressed gas adjusted by the compressed gas adjustment means 2 . The mixture that has passed through the introduction pipe 3 is uniformly dispersed by a conical protruding member 4 provided in the central part of the raw material supply means, and is guided to the supply pipes 5 extending radially in eight directions to be heat-treated in the processing chamber. lead to 6.

At this time, the flow of the mixture supplied to the processing chamber 6 is regulated by the regulating means 9 provided in the processing chamber for regulating the flow of the mixture. Therefore, the mixture supplied to the processing chamber is heat-treated while swirling in the processing chamber, and then cooled.
Hot air for heat-treating the supplied mixture is supplied from the hot air supply means 7, distributed by the distribution member 12, and introduced into the processing chamber by spirally turning the hot air by the turning member 13 for turning the hot air. be done. As for the configuration, the swirling member 13 for swirling the hot air has a plurality of blades, and the swirling of the hot air can be controlled by the number and angle of the blades. The hot air supplied into the processing chamber preferably has a temperature of 100° C. to 300° C. at the outlet 11 of the hot air supplying means. If the temperature at the outlet 11 of the hot air supply means is within the above range, the toner can be uniformly spheroidized while suppressing fusion and coalescence of the toner due to overheating of the mixture.

Furthermore, the heat-treated toner that has been subjected to heat treatment is cooled by cold air supplied from the cold air supply means 8, and the temperature supplied from the cold air supply means 8 is preferably -20.degree. C. to 30.degree. If the temperature of the cold air is within the above range, the heat-treated toner can be efficiently cooled, and fusion and coalescence of the heat-treated toner can be suppressed without impeding uniform spheroidizing treatment of the mixture. can. The absolute water content of the cool air is preferably 0.5 g/m ³ or more and 15.0 g/m ³ or less.

Next, the cooled heat-treated toner is recovered by a recovery means 10 at the lower end of the processing chamber 6 . A blower (not shown) is provided at the end of the recovering means, so that the particles are sucked and conveyed.
The powder particle supply port 14 is provided so that the swirling direction of the supplied mixture and the swirling direction of the hot air are the same. It is provided on the outer periphery of the processing chamber 6 so as to maintain the turning direction. Furthermore, the cold air supplied from the cold air supply means 8 is configured to be supplied horizontally and tangentially from the outer peripheral portion of the apparatus to the inner peripheral surface of the processing chamber. The swirling direction of the toner supplied from the powder particle supply port 14, the swirling direction of the cold air supplied from the cool air supplying means 8, and the swirling direction of the hot air supplied from the hot air supplying means 7 are all the same. As a result, turbulence does not occur in the processing chamber, the swirling flow in the device is strengthened, and a strong centrifugal force is applied to the toner, further improving the dispersibility of the toner. can be obtained.
The average circularity of the toner is preferably 0.960 or more and 0.980 or less from the viewpoint of excellent toner chargeability.

After that, it is classified using the following classifier or sieving machine as necessary.
Classifier/sieving machine: Inertial classifier Elbow Jet (manufactured by Nittetsu Mining Co., Ltd.), Centrifugal classifier Turboplex (manufactured by Hosokawa Micron Corporation), TSP Separator (manufactured by Hosokawa Micron Corporation), Faculty (Hosokawa Micron Corporation) (manufactured by Co., Ltd.), etc. After that, the surfaces of the obtained heat-treated toner particles having a desired particle size are externally added with a desired amount of an external additive. Examples of the method for external addition treatment include a method of stirring and mixing using the following mixing apparatus as an external addition device.
Mixing equipment: Double-con mixer, V-type mixer, Drum-type mixer, Super mixer, Henschel mixer, Nauta mixer, Mechanohybrid (manufactured by Nippon Coke Industry Co., Ltd.), Nobilta (manufactured by Hosokawa Micron Co., Ltd.), etc. At that time, if necessary In addition, an external additive such as a fluidizing agent may be externally added.

Examples of external additives include resin fine particles and inorganic fine particles that function as charge aids, conductivity imparting agents, fluidity imparting agents, anti-caking agents, release agents during fixing with hot rollers, lubricants, and abrasives. is mentioned. Lubricants include polyethylene fluoride fine particles, zinc stearate fine particles, and polyvinylidene fluoride fine particles. Examples of abrasives include cerium oxide fine particles, silicon carbide fine particles, and strontium titanate fine particles.
In the present invention, the inorganic fine particles A and the silica fine particles B are preferably externally added before the surface treatment (heat treatment) by heating, and then embedded in the surface of the toner particles by heat treatment.
Methods for measuring various physical properties of toner and raw materials are described below.

<Washing method>
In the present invention, the washing treatment was performed as follows. A sucrose aqueous solution prepared by dissolving 31.1 g of sucrose (manufactured by Kishida Kagaku Co., Ltd.) in 10.3 g of ion-exchanged water was added with 6 cc of the following Contaminon N in a 30 cc glass vial, and mixed thoroughly. A dispersion is made.
Contaminon N: pH 7 neutral detergent for cleaning precision measuring instruments consisting of a nonionic surfactant, an anionic surfactant, and an organic builder, manufactured by Wako Pure Chemical Industries, Ltd. Glass vial: manufactured by Nichiden Rika Glass Co., Ltd., VCV-30, outer diameter: 35 mm, height: 70 mm

1.0 g of toner is added to this glass vial and allowed to stand until the toner spontaneously settles to prepare a pretreatment dispersion. This dispersion was shaken at a shaking speed of 200 rpm for 5 minutes with a shaker (YS-8D type: manufactured by Yayoi Co., Ltd.) to separate the inorganic fine particles from the surfaces of the toner particles. A centrifugal separator is used to separate the "toner with inorganic fine particles remaining on the surface" and the "inorganic fine particles separated from the surface of the toner particles". The centrifugation step was performed at 3700 rpm for 30 minutes. The toner with residual inorganic fine particles is collected by suction filtration and dried to obtain a washed toner.

<Method for Measuring Number Average Particle Diameter (D1) of Primary Particles of Inorganic Fine Particles A and Silica Fine Particles B Contained in Toner After Washing with Water>
A cross section of the washed toner obtained by the water washing treatment method is observed with a scanning transmission electron microscope (STEM) to obtain an STEM image. Then, based on the obtained STEM image, the number average particle diameter (D1) of the primary particles of the inorganic fine particles A and the silica fine particles B is calculated.

A cross-sectional image of the washed toner is obtained by the following method.
(1) Sprinkle the toner in one layer on the cover glass.
(2) Next, a PTFE (polytetrafluoroethylene) tube (1.5 mm inner diameter x 3 mm outer diameter x 3 mm length) is filled with a photocurable resin D800 (manufactured by JEOL Ltd.). Then, the cover glass is gently placed on the tube in such a direction that the toner is in contact with the photocurable resin D800. In this state, light is irradiated to cure the resin, and then the cover glass and the tube are removed to form a columnar resin in which the toner is embedded on the outermost surface.

(3) Using an ultrasonic ultramicrotome (Leica, UC7), at a cutting speed of 0.6 mm/s, the radius of the toner from the outermost surface of the cylindrical resin (for example, the weight average particle diameter (D4) is 10.0 μm). 5.0 μm in some cases) to expose the cross section of the center of the toner.
(4) Next, the toner is cut so as to have a film thickness of 250 nm, and a thin piece sample of the cross section of the toner is produced. A cross section of the central portion of the toner can be obtained by cutting by such a method.

(5) STEM images are produced using the scanning image mode of a scanning transmission electron microscope (JEM2800, JEOL Ltd.).
The probe size used for taking STEM images was 1 nm, and the image size was 1024×1024 pixels. In the bright-field image, the Detector Control panel Contrast was adjusted to 1425, Brightness to 3750, Image Control panel Contrast to 0.0, Brightness to 0.5, and Gammma to 1.00 to obtain an image. One image is acquired for one toner, and images are acquired for at least 25 toners.

The particle size of the primary particles of 100 inorganic fine particles A and silica fine particles B is randomly measured for one toner to obtain the number average particle size. The particle size of the primary particles may be measured manually or using a measurement tool.
When measuring the particle diameters of the inorganic fine particles A and the silica fine particles B in the cross section of one toner, the inorganic fine particles A and the silica fine particles B in the cross section of the toner are preliminarily analyzed by elemental analysis using an energy dispersive X-ray spectrometer (EDS). The silica fine particles B are specified and measured.

<Method for Measuring Content of Inorganic Fine Particles A Contained in Toner After Washing>
The content of the inorganic fine particles A is calculated from the fluorescent X-ray measurement for the washed toner obtained by the above water washing treatment method.
Fluorescent X-ray measurement of each element conforms to JIS K 0119-1969, but specifically as follows.

As a measurement device, a wavelength dispersive X-ray fluorescence spectrometer "Axios" (manufactured by PANalytical) and attached dedicated software "SuperQ ver.4.0F" (manufactured by PANalytical) for setting measurement conditions and analyzing measurement data ). Rh is used as the anode of the X-ray tube, the measurement atmosphere is vacuum, the measurement diameter (collimator mask diameter) is 27 mm, and the measurement time is 10 seconds. A proportional counter (PC) is used to measure light elements, and a scintillation counter (SC) is used to measure heavy elements.
As a measurement sample, about 4 g of inorganic fine particles were placed in a special aluminum ring for pressing, flattened, and pressed at 20 MPa for 60 seconds using the following tablet molding compression machine to obtain a sample having a thickness of about 2 mm and a diameter of about 2 mm. Pellets molded to about 39 mm are used.
Tablet molding compressor "BRE-32" (manufactured by Mayekawa Test Instruments Co., Ltd.)

The measurement is performed under the above conditions, and the element derived from the inorganic fine particle A is identified based on the obtained X-ray peak position, and the count rate (unit: cps), which is the number of X-ray photons per unit time, is used to determine the inorganic fine particle. Calculate the content of A.
The element derived from the inorganic fine particles A is, for example, a strontium element when the inorganic fine particles A are strontium titanate fine particles.

<Method of Measuring Coverage X by Inorganic Fine Particles A and Coverage Y by Silica Fine Particles B, Measured by X-ray Photoelectron Spectrometer (ESCA) in Toner Washed with Water>
The coverage X of the inorganic fine particles A and the coverage Y of the silica fine particles B in the washed toner are calculated by surface composition analysis using an X-ray photoelectron spectroscopy (ESCA) apparatus. The ESCA apparatus and measurement conditions are as follows.
Measurement sample:
About 2 g of toner after washing with water was placed in a special aluminum ring for pressing and leveled. A pellet is used which is molded to a thickness of about 2 mm and a diameter of about 20 mm by pressing for 2 seconds.
The molded pellet was attached to a 20 mm diameter platen attached to the ESCA device with a carbon tape or the like, and measured.
Equipment used:
PHI5000VersaProbe II manufactured by ULVAC-Phi, Inc.
Irradiation: Al-Kα ray Output: 100 μm 25 W 15 kV
Photoelectron uptake angle; 45°
Pass Energy; 58.70 eV
Step size; 0.125eV
From the peak intensity of each element measured under the above conditions, the surface atomic concentration (atomic %) is calculated using the relative sensitivity factor provided by ULVAC-Phi, Inc. As elements to be measured, C, O, Si, and elements derived from the inorganic fine particles A (for example, Ti and Sr when the inorganic fine particles A are strontium titanate fine particles) were measured.
The coverage X of the inorganic fine particles A and the coverage Y of the silica fine particles B in the toner after washing with water are obtained from the following equations.
Coverage [X] = 100 x C1/C3
Coverage [Y] = 100 x C2/C3
[In the formula,
C1 is an abundance ratio [atm%] of an element derived from the inorganic fine particles A in the toner (for example, Sr when the inorganic fine particles A are strontium titanate fine particles) calculated by X-ray photoelectron spectroscopic analysis;
C2 is the Si abundance ratio in the toner calculated by X-ray photoelectron spectroscopy;
C3 is the C abundance ratio, O abundance ratio, Si abundance ratio, and the abundance ratio of elements derived from inorganic fine particles A (for example, Ti and Sr in the case of strontium titanate) in the toner calculated by X-ray photoelectron spectroscopic analysis. sum [atm %]. ]
The coverage [X] can be controlled by the particle size of the inorganic fine particles A and the amount added. The coverage [Y] can be controlled by the particle size of the silica fine particles B and the amount added.

<Method for measuring dielectric constant of inorganic fine particles A>
A 284A precision LCR meter (manufactured by Hewlett-Packard) is used to measure the complex permittivity at a frequency of 1 MHz after calibration at frequencies of 1 kHz and 1 MHz.
A load of 39,200 kPa (400 kg/cm ² ) is applied to the sample for 5 minutes to form a disc having a diameter of 25 mm and a thickness of 1 mm or less (approximately 0.5 mm to 0.9 mm).
The obtained measurement sample is mounted on ARES (manufactured by Rheometric Scientific F.E. Co., Ltd.) equipped with a dielectric constant measurement jig (electrode) having a diameter of 25 mm, and is heated to 0.49 N ( The dielectric constant is measured at a frequency of 1 MHz under a load of 50 g).

EXAMPLES The present invention will be described in more detail below using Examples and Comparative Examples, but the aspects of the present invention are not limited to these. All parts and percentages in Examples and Comparative Examples are based on mass unless otherwise specified.
<Production example of inorganic fine particles A-1>
Metatitanic acid produced by the sulfuric acid method is deironized and bleached, then desulfurized by adding a 3 mol/L sodium hydroxide aqueous solution to pH 9.0, and then neutralized to pH 5.6 with 5 mol/L hydrochloric acid. , was filtered and washed. Water was added to the washed cake to obtain a slurry of 1.90 mol/L as TiO ₂ , and then hydrochloric acid was added to adjust the pH to 1.4 for deflocculation.

1.90 mol of metatitanic acid, which had undergone desulfurization and deflocculation, was taken as TiO ₂ and put into a 3 L reactor. After adding 2.185 mol of an aqueous strontium chloride solution to the peptized metatitanic acid slurry so that the SrO/TiO ₂ (molar ratio) was 1.15, the TiO ₂ concentration was adjusted to 1.039 mol/L.

Next, after heating to 90° C. while stirring and mixing, 440 mL of a 10 mol/L sodium hydroxide aqueous solution was added over 40 minutes, then stirring was continued at 95° C. for 45 minutes, and the mixture was poured into ice water. The reaction was terminated by quenching.
The reaction slurry was heated to 70° C., 12 mol/L hydrochloric acid was added until the pH reached 5.0, stirring was continued for 1 hour, and the resulting precipitate was decanted.

The resulting slurry containing the precipitate was adjusted to 40° C. and adjusted to pH 2.5 by adding hydrochloric acid. After that, 4.0% by mass of 3,3,3-trifluoropropyltrimethoxysilane with respect to the solid content as the surface treatment agent 1 and 4.0% by mass of isobutyl trimethoxysilane as the surface treatment agent 2 with respect to the solid content. Methoxysilane was added and stirred for 10 hours. After adjusting the pH to 6.5 by adding a 5 mol/L sodium hydroxide aqueous solution and continuing stirring for 1 hour, filtration and washing are performed, and the resulting cake is dried in the air at 120° C. for 8 hours to obtain inorganic fine particles A-. got 1. The obtained inorganic fine particles A-1 had a dielectric constant of 70 Pf/m and a number average particle diameter (D1) of primary particles of 40 nm. Physical properties are shown in Table 1.

<Production Examples of Inorganic Fine Particles A-2 to A-6>
In the production example of inorganic fine particles A-1, the concentration of TiO ₂ in the mixed solution after addition of the aqueous strontium chloride solution, the dropping time of the aqueous sodium hydroxide solution, the stirring time after dropping, and the presence or absence of quenching are shown in Table 1. changed to Inorganic fine particles A-2 to A-6 were obtained in the same manner as in the production example of inorganic fine particles A-1 except for such changes. Physical properties are shown in Table 1.

<Production Examples of Inorganic Fine Particles A-7 and A-8>
In the production example of inorganic fine particles A-1, the concentration of TiO ₂ in the mixed solution after addition of the aqueous strontium chloride solution, the dropping time of the aqueous sodium hydroxide solution, the stirring time after dropping, and the presence or absence of quenching are shown in Table 1. and did not use the surface treatment agent 1. Inorganic fine particles A-7 and A-8 were obtained in the same manner as in the production example of inorganic fine particles A-1 except for these changes. Physical properties are shown in Table 1.

<Production example of inorganic fine particles A-9 and A-10>
In the production example of inorganic fine particles A-1, the concentration of TiO ₂ in the mixed solution after addition of the aqueous strontium chloride solution, the dropping time of the aqueous sodium hydroxide solution, the stirring time after dropping, and the presence or absence of quenching are shown in Table 1. , and surface treatment agents 1 and 2 were not used. Inorganic fine particles A-9 and A-10 were obtained in the same manner as in the production example of inorganic fine particles A-1 except for these changes. Physical properties are shown in Table 1.

<Production example of inorganic fine particles A-11>
Zirconium oxide (number average particle size of primary particles: 30 nm, purity: 97.0% by mass) and strontium carbonate (number average particle size of primary particles: 30 nm, purity: 99.0% by mass) are each dispersed in water. to prepare a slurry.
Each slurry was mixed so that the molar ratio of zirconium and strontium was 1:1 to obtain a mixed slurry.
The resulting mixed slurry was spray dried at 200°C. Thereafter, the spray-dried powder was heated in an electric furnace at a temperature of 800° C. for 4 hours to obtain inorganic fine particles A-11. The obtained inorganic fine particles A-11 had a dielectric constant of 97 Pf/m and a number average particle diameter (D1) of primary particles of 95 nm.

<Production example of inorganic fine particles A-12>
Inorganic fine particles A-12 were obtained in the same manner as in the production example of inorganic fine particles A-11, except that the firing time in the electric furnace was changed to 4.5 hours. The obtained inorganic fine particles A-12 had a dielectric constant of 100 Pf/m and a number average particle diameter (D1) of primary particles of 100 nm.
<Production example of inorganic fine particles A-13>
Zirconium oxide (number average particle size of primary particles: 2 nm, purity: 97.0% by mass) and strontium carbonate (number average particle size of primary particles: 2 nm, purity: 99.5% by mass) are each dispersed in water. A slurry was prepared.
Each slurry was mixed so that the molar ratio of zirconium and strontium was 1:0.94 to obtain a mixed slurry.
The resulting mixed slurry was spray dried at 130°C. Thereafter, the spray-dried powder was heated in an electric furnace at a temperature of 650° C. for 2 hours to obtain inorganic fine particles 13 . The obtained inorganic fine particles A-13 had a dielectric constant of 35 Pf/m and a number average particle diameter (D1) of primary particles of 5 nm.
<Production example of inorganic fine particles A-14>
Inorganic fine particles A-14 were obtained in the same manner as in the production example of inorganic fine particles A-13, except that the firing time in the electric furnace was changed to 2.5 hours. The obtained inorganic fine particles A-14 had a dielectric constant of 39 Pf/m and a number average particle diameter (D1) of primary particles of 10 nm.

<Production example of silica fine particles B-1>
A hydrocarbon-oxygen mixed burner having a double-tube structure capable of forming an inner flame and an outer flame was used as the combustion furnace for producing the silica fine particles B-1. A two-fluid nozzle for slurry injection is grounded at the center of the burner, and the raw silicon compound is introduced. A hydrocarbon-oxygen combustible gas is injected from around the two-fluid nozzle to form an inner flame and an outer flame, which are reducing atmospheres. By controlling the amount and flow rate of the combustible gas and oxygen, the atmosphere, temperature, flame length, etc. are adjusted. Silica fine particles are formed from the silicon compound in the flame, and are fused until they reach a desired particle size. Then, after cooling, it is obtained by collecting with a bag filter or the like.
Silica fine particles were produced using hexamethylcyclotrisiloxane as a raw material silicon compound, and 100 parts by mass of the obtained silica fine particles were surface-treated with 4% by mass of hexamethyldisilazane. Physical properties are shown in Table 2.

<Production Examples of Silica Fine Particles B-2 to B-10>
In the same manner as for silica fine particles B-1, after adjusting the flame size, temperature and flow rate of the burner to obtain particles with different particle sizes, surface treatment is performed with 4% by mass of hexamethyldisilazane to obtain silica fine particles B-2. ~B-10 was obtained. Physical properties are shown in Table 2.

<Production Example of Titanium Oxide Fine Particles 1>
An ilmenite ore containing 50% by mass of TiO ₂ equivalent was used as a starting material. After drying this raw material at a temperature of 150° C. for 2 hours, sulfuric acid was added and dissolved to obtain an aqueous solution of TiOSO ₂ . Sodium carbonate was added to this aqueous solution to adjust the pH to 9.0 for alkali neutralization, followed by filtration to obtain a white precipitate. Pure water was added to this white precipitate, and the mixture was heated for 2.5 hours while maintaining the temperature at about 90° C. for hydrolysis treatment, followed by repeated filtration and washing with water to obtain anatase titanium oxide.

The resulting anatase-type titanium oxide was sintered by heating at a high temperature of 1100° C. to obtain rutile-type titanium oxide. This rutile-type titanium oxide was pulverized in a jet mill to obtain fine titanium oxide particles. The titanium oxide fine particles were dispersed in ethanol, and 10 parts by mass of isobutyltrimethoxysilane as a hydrophobizing agent was added to 100 parts by mass of the titanium oxide fine particles, and the particles were sufficiently stirred so as not to cause coalescence of the particles. It was added dropwise while mixing, reacted, and subjected to hydrophobization treatment.

The pH of the slurry was adjusted to 6.5 with further thorough stirring. After filtration and drying, the mixture was heat-treated at a temperature of 170° C. for 2 hours. The dielectric constant of the titanium oxide fine particles 1 was 25 Pf/m, and the number average particle size of the primary particles was 10 nm.

<Production example of binder resin>
(Production example of polyester resin C)
- Polyoxypropylene (2.2)-2,2-bis(4-hydroxyphenyl)propane:
80.0 mol% with respect to the total number of moles of polyhydric alcohol
- Polyoxyethylene (2.2)-2,2-bis(4-hydroxyphenyl)propane:
20.0 mol% with respect to the total number of moles of polyhydric alcohol
・Terephthalic acid: 80.0 mol% with respect to the total number of moles of polyvalent carboxylic acid
- Trimellitic anhydride: 20.0 mol% with respect to the total number of moles of polyvalent carboxylic acid
The above materials were put into a reactor equipped with a condenser, a stirrer, a nitrogen inlet tube, and a thermocouple. Then, 0.2 parts by mass of titanium tetrabutoxide was added as a catalyst to 100 parts by mass of the total amount of monomers. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was carried out for 2.5 hours while stirring at a temperature of 200°C.
Furthermore, after reducing the pressure in the reaction tank to 8.3 kPa and maintaining it for 1 hour, it was cooled to 180 ° C. and reacted as it was. After confirming that the softening point measured according to ASTM D36-86 reached 110 ° C. The temperature was lowered to stop the reaction.

<Production Example of Toner 1>
· Polyester resin C 100.0 parts · 3,5-di-t-butylsalicylic acid aluminum compound 0.1 parts · Fischer-Tropsch wax (maximum endothermic peak temperature 90°C) 5.0 parts · C.I. I. Pigment Blue 15:3 5.0 parts The above materials were mixed using a Henschel mixer (FM-75 model, manufactured by Mitsui Mining Co., Ltd.) at a rotation speed of 1500 rpm for a rotation time of 5 minutes, and then the temperature was set to 130 ° C. The mixture was kneaded with a twin-screw kneader (Model PCM-30, manufactured by Ikegai Co., Ltd.). The resulting kneaded product was cooled and coarsely pulverized to 1 mm or less with a hammer mill to obtain a coarsely pulverized product. The coarsely crushed product obtained was finely pulverized with a mechanical pulverizer (T-250, manufactured by Turbo Kogyo Co., Ltd.). Further, classification was performed using Faculty (F-300, manufactured by Hosokawa Micron Corporation) to obtain Toner Particles 1 . The operating conditions were a classification rotor rotation speed of 11000 rpm and a dispersion rotor rotation speed of 7200 rpm.

・Toner particles 1 100 parts ・Inorganic fine particles A-1 5.0 parts ・Silica fine particles B-1 4.0 parts After mixing at a rotation speed of 2000 rpm for a rotation time of 2 minutes, heat treatment was performed by the surface treatment apparatus shown in FIG. The operating conditions were feed rate = 5 kg/hr, hot air temperature C = 160°C, hot air flow rate = 6 m3/min. , cold air temperature E=-5° C., cold air flow rate=4 m3/min. , blower air volume = 20 m3/min. , injection air flow rate=1 m3/min. and
The obtained heat-treated toner 1 was classified using an inertia classifier elbow jet (manufactured by Nittetsu Mining Co., Ltd.) to obtain heat-treated toner 1M.

・Heat treated toner 1M 100 parts ・Inorganic fine particles A-1 0.5 parts ・Silica fine particles B-1 0.5 parts ・Silica fine particles (number average particle diameter (D1) of primary particles is 10 nm) 1.5 parts The indicated raw materials were mixed using a Henschel mixer (FM-10C type, manufactured by Nippon Coke Kogyo Co., Ltd.) at a rotation speed of 67 s ^-1 (4000 rpm) for a rotation time of 2 minutes, and then an ultrasonic vibrating sieve with an opening of 54 μm. and Toner 1 was obtained. Physical properties are shown in Table 3.

<Manufacturing Examples of Toners 2 to 18>
In Production Example of Toner 1, the same procedure as in Production Example of Toner 1 was performed, except that the type of inorganic fine particles A, the type of silica fine particles B, and the number of parts added were changed so that the physical properties of the toner after washing with water were as shown in Table 3. The operation was performed to obtain Toners 2-18. Physical properties are shown in Table 3.

<Production Example of Magnetic Core Particle 1>
- Process 1 (weighing/mixing process):
Fe ₂ O ₃ 62.7 parts MnCO ₃ 29.5 parts Mg(OH) ₂ 6.8 parts SrCO ₃ 1.0 parts Ferrite raw materials were weighed so as to achieve the above composition ratio. After that, it was pulverized and mixed for 5 hours in a dry vibration mill using stainless beads having a diameter of 1/8 inch.

・Step 2 (temporary firing step):
The pulverized material thus obtained was made into pellets of about 1 mm square by a roller compactor. Coarse powder was removed from the pellets with a vibrating sieve with an opening of 3 mm, and then fine powder was removed with a vibrating sieve with an opening of 0.5 mm. 01% by volume) and fired at a temperature of 1000° C. for 4 hours to produce a calcined ferrite. The composition of the obtained calcined ferrite is as follows.
(MnO)a(MgO)b(SrO) _c ( _Fe2O3 )d
In the above formula, a=0.257, b=0.117, c=0.007 and d=0.393.

・Step 3 (crushing step):
After crushing the obtained calcined ferrite to about 0.3 mm with a crusher, 30 parts of water was added to 100 parts of calcined ferrite using zirconia beads with a diameter of 1/8 inch, and the mixture was crushed with a wet ball mill for 1 hour. . The obtained slurry was pulverized for 4 hours in a wet ball mill using alumina beads having a diameter of 1/16 inch to obtain a ferrite slurry (fine pulverized product of calcined ferrite).

- Step 4 (granulation step):
To the ferrite slurry, 1.0 parts of ammonium polycarboxylate as a dispersant and 2.0 parts of polyvinyl alcohol as a binder are added to 100 parts of calcined ferrite. Granulated into spherical particles. After adjusting the particle size of the obtained particles, they were heated at 650° C. for 2 hours using a rotary kiln to remove the organic components of the dispersant and binder.

- Step 5 (firing step):
In order to control the sintering atmosphere, the temperature was raised from room temperature to 1300° C. in 2 hours in an electric furnace under a nitrogen atmosphere (oxygen concentration 1.00% by volume), and then sintered at 1150° C. for 4 hours. After that, the temperature was lowered to 60° C. over 4 hours, the nitrogen atmosphere was returned to the air, and the temperature was 40° C. or less and taken out.

・Step 6 (sorting step):
After crushing the aggregated particles, the low magnetic force products are cut by magnetic separation, sieved with a sieve with an opening of 250 μm to remove coarse particles, and the 50% particle size (D50) of 37.0 μm based on volume distribution. A magnetic core particle 1 was obtained.

<Preparation of Coating Resin 1>
Cyclohexyl methacrylate monomer 26.8% by mass
Methyl methacrylate monomer 0.2% by mass
Methyl methacrylate macromonomer 8.4% by mass
(Macromonomer with a weight-average molecular weight of 5,000 having a methacryloyl group at one end)
Toluene 31.3% by mass
Methyl ethyl ketone 31.3% by mass
Azobisisobutyronitrile 2.0% by mass

Among the above materials, cyclohexyl methacrylate monomer, methyl methacrylate monomer, methyl methacrylate macromonomer, toluene, and methyl ethyl ketone were placed in a four-necked separable flask equipped with a reflux condenser, thermometer, nitrogen inlet tube, and stirrer, and nitrogen was added. Gas was introduced to create a nitrogen atmosphere. After that, the mixture was heated to 80° C., azobisisobutyronitrile was added, and the mixture was refluxed for 5 hours for polymerization. Hexane was injected into the obtained reactant to precipitate the copolymer, and the precipitate was separated by filtration and dried in vacuum to obtain Coating Resin 1.
Then, 30 parts of coating resin 1 was dissolved in 40 parts of toluene and 30 parts of methyl ethyl ketone to obtain polymer solution 1 (solid content: 30% by mass).

<Preparation of coating resin solution 1>
Polymer solution 1 (resin solid content concentration 30%) 33.3% by mass
Toluene 66.4% by mass
Carbon black Regal 330 (manufactured by Cabot) 0.3% by mass
(Primary particle size 25 nm, nitrogen adsorption specific surface area 94 m ² /g, DBP oil absorption 75 mL/100 g)
The above material was dispersed with a paint shaker for 1 hour using zirconia beads with a diameter of 0.5 mm. The resulting dispersion was filtered through a 5.0 μm membrane filter to obtain a coating resin solution 1.

<Manufacturing Example of Magnetic Carrier 1>
(Resin coating step):
The magnetic core particles 1 and the coating resin solution 1 were put into a vacuum degassing kneader maintained at room temperature (the amount of the coating resin solution added was 2.5 parts as a resin component for 100 parts of the magnetic core particles 1). portion). After charging, the mixture was stirred at a rotation speed of 30 rpm for 15 minutes, and after a certain amount or more of the solvent (80% by mass) was volatilized, the temperature was raised to 80° C. while mixing under reduced pressure, toluene was distilled off over 2 hours, and then the mixture was cooled. The obtained magnetic carrier is separated into low magnetic products by magnetic separation, passed through a sieve with an opening of 70 μm, and then classified by an air classifier to obtain a magnetic carrier having a 50% particle size (D50) of 38.2 μm based on volume distribution. got 1.

<Production example of two-component developer 1>
92.0 parts of the magnetic carrier 1 and 8.0 parts of the toner 1 were mixed by a V-type mixer (V-20, manufactured by Seishin Enterprise Co., Ltd.) to obtain a two-component developer 1.

<Production Examples of Two-Component Developers 2 to 18>
Two-component developers 2 to 18 were obtained in the same manner as in the production example of two-component developer 1 except for making changes as shown in Table 4.

<Example 1>
The following evaluations were carried out using a full-color copying machine imagePRESS C800 manufactured by Canon Inc. or a modified machine thereof.
The image forming apparatus has a photoreceptor for forming an electrostatic latent image as an image carrier, and has a developing process for developing the electrostatic latent image on the photoreceptor into a toner image with a two-component developer.
Further, it has a transfer step of transferring the developed toner image to an intermediate transfer member, then transferring the toner image from the intermediate transfer member to paper, and a fixing step of fixing the toner image on the paper with heat.
Two-component developer 1 was put into the developing device of the station of the process cartridge for cyan color of this image forming apparatus, and the following evaluation was performed.

<Evaluation of Dot Reproducibility>
After continuously outputting up to 10,000 copies of a test chart with a print ratio of 5% in a low temperature and low humidity environment (temperature of 5°C, relative humidity of 5%), a halftone (30h) image is formed. was evaluated based on the criteria of
High whiteness paper GF-C081 (81.4 g/m ² , Canon Marketing Japan Inc.) was used as a recording medium. The 30h image is a value obtained by expressing 256 gradations in hexadecimal, and is a halftone image when 00h is solid white (non-image) and FFh is a solid image (full image).
Images were obtained by measuring the area of 1,000 dots using a digital microscope VHX-500 (lens wide range zoom lens VH-Z100 manufactured by Keyence Corporation).
The number average (S) of the dot area and the standard deviation (σ) of the dot area were calculated, and the dot reproducibility index was calculated by the following formula.
Then, the dot reproducibility index (I) of the halftone image was evaluated. The smaller the dot reproducibility index (I), the better the dot reproducibility.
Dot reproducibility index (I) = σ/S x 100
(Evaluation criteria)
A: I is less than 1.0 B: I is 1.0 or more and less than 2.0 C: I is 2.0 or more and less than 4.0 D: I is 4.0 or more and less than 6.0 E: I is 6.0 0 or more and less than 8.0 F: I is 8.0 or more

<Evaluation of electrostatic offset>
High-quality paper (npi high-quality: 157.0 g/m ² , Nippon Paper Industries Co., Ltd.) was used as the recording medium. Prior to the evaluation, the recording medium was allowed to stand in a low-temperature, low-humidity environment (temperature of 5° C., relative humidity of 5%) for 48 hours or more to dry sufficiently to reduce the water content to less than 3%.
After continuously outputting up to 10,000 copies of a test chart with a print ratio of 5% under a low temperature and low humidity environment (temperature of 5°C, relative humidity of 5%), 500 images were continuously printed using the following electrostatic offset test chart. I did
Chart for electrostatic offset testing:
In the front half of the image, 15 lines with a width of 0.2 mm and a width of 1 cm are drawn so as to be perpendicular to the traveling direction of the transfer material. The rear half of the image is a white background,
The white background portion of this image was observed with an optical microscope (magnification of 30 times) to evaluate the electrostatic offset property.
A: Even if it is magnified with an optical microscope, not even a single sheet with electrostatic offset can be confirmed.
B: When magnified with an optical microscope, a slight electrostatic offset can be confirmed on one sheet.
C: When magnified with an optical microscope, a slight electrostatic offset can be confirmed on 2 or more and 3 or less sheets.
D: When magnified with an optical microscope, a slight electrostatic offset can be confirmed on 4 or more and 5 or less sheets.
E: When magnified with an optical microscope, a slight electrostatic offset can be confirmed in 6 to 9 sheets.
F: When magnified with an optical microscope, a slight electrostatic offset can be confirmed on 10 or more sheets.

<Evaluation of Fixing Explosion>
Recycled paper (GF-R070: 67.0 g/m ² , Canon Marketing Japan Inc.) was used as the recording medium. Prior to the evaluation, the recording medium was allowed to stand in a high-temperature and high-humidity environment (temperature of 30° C., relative humidity of 80%) for 48 hours or more to sufficiently absorb moisture, and the water content was adjusted to 9% or more.
Under a high temperature and high humidity environment (temperature 30°C, relative humidity 80%), using a horizontal line image chart in which 4 dot lines are arranged with 20 dot spaces, trailing generated from horizontal lines on the image is counted and the following criteria are used. Judged.
A: No trailing occurred.
B: One or less tailing occurs per horizontal line.
C: Occurrence of more than 1 but not more than 2 tailings per horizontal line.
D: More than 2 and 3 or less tailing occurred per horizontal line.
E: More than 3 but not more than 4 tailing occurred per horizontal line.
F: More than 4 and 5 or more tailings per horizontal line.

<Evaluation of Image Density>
Evaluation was performed under the following environments by continuously outputting up to 10,000 copies of a test chart with a print ratio of 5%, and then outputting an original image with five 20mm square solid image patches arranged within the development area. The average image density (image density) was evaluated according to the following criteria.
Normal temperature and normal humidity (temperature 23°C, relative humidity 55%) environment Low temperature and low humidity environment (temperature 5°C, relative humidity 5%) High temperature and high humidity environment (temperature 30°C, relative humidity 80%) Bleached paper (CS -068: 68.0 g/m ² paper, A4, sold by Canon Marketing Japan Inc.) was used.
The image density was measured using an X-Rite color reflection densitometer (manufactured by X-rite, X-rite 500 Series).
(Evaluation criteria)
A: Image density 1.40 or more B: Image density 1.30 or more and less than 1.40 C: Image density less than 1.30

<Evaluation of Fog>
Evaluation was performed by continuously outputting 10,000 sheets of images with a print ratio of 5% and then outputting a solid white image under each of the following environments, and evaluated according to the following criteria.
Normal temperature and normal humidity (temperature 23°C, relative humidity 55%) environment Low temperature and low humidity environment (temperature 5°C, relative humidity 5%) High temperature and high humidity environment (temperature 30°C, relative humidity 80%) Bleached paper (CS -068: 68.0 g/m ² paper, A4, sold by Canon Marketing Japan Inc.) was used.
The measurement was performed using a reflectometer (reflectometer model TC-6DS manufactured by Tokyo Denshoku Co., Ltd.). The fog was evaluated by taking the average density as Dr and the amount of fog as Dr-Ds. Therefore, a smaller numerical value indicates less fog.
(Evaluation criteria)
A: Fog less than 1.00 B: Fog 1.00 or more and less than 3.00 C: Fog 3.00 or more

<Examples 2 to 18>
Two-component developers 2 to 18 were evaluated in the same manner as in Example 1. Table 5 shows the evaluation results.

<Production Example of Toner 19>
In Production Example of Toner 1, Toner 19 was obtained by carrying out the same operations as in Production Example of Toner 1 except for the following changes so that the physical properties of the toner after washing with water would be the values shown in Table 6. Physical properties are shown in Table 6.
Changes: The type of inorganic fine particles A, the type of silica fine particles B, and the number of parts added were changed, and only the silica fine particles B were added before the hot-air treatment, and the inorganic fine particles A were added only after the hot-air treatment.

<Manufacturing Examples of Toners 20 and 22>
In the production example of toner 1, the type of inorganic fine particles A, the type of silica fine particles B, and the number of parts added were changed so that the physical properties of the toner after washing with water were as shown in Table 6, and the hot air treatment was not performed. Toners 20 and 22 were obtained by performing the same operation as in Production Example 1. Physical properties are shown in Table 6.

<Manufacturing Example of Toner 21>
In Production Example of Toner 1, Toner 21 was obtained by carrying out the same operations as in Production Example of Toner 1 except for the following changes so that the physical properties of the toner after washing with water would be the values shown in Table 6. Physical properties are shown in Table 6.
Changes: Titanium oxide fine particles 1 were used instead of inorganic fine particles A, the number of titanium oxide fine particles 1 added, the type and number of silica fine particles B added were changed, and hot air treatment was not performed.

<Production Examples of Two-Component Developers 19 to 22>
Two-component developers 19 to 22 were obtained in the same manner as in Production Example of Two-component Developer 1 except for making changes as shown in Table 7.

<Comparative Examples 1 to 4>
Two-component developers 19 to 22 were evaluated in the same manner as in Example 1. Table 8 shows the evaluation results.

1. Raw material constant supply means2. Compressed gas flow rate adjusting means3. Introductory tube 4 . Protrusive member 5 . supply pipe6. processing chamber 7 . Hot air supply means8. Cool air supply means 9 . regulatory means 10 . collection means 11 . Hot air supply means outlet 12 . Distribution member
13. Pivoting member 14 . Powder particle supply port

Claims (8)

A toner having toner particles and inorganic fine particles A and silica fine particles B present on the surfaces of the toner particles,
The inorganic fine particles A have a dielectric constant of 35 pF/m or more and 100 pF/m or less in a dielectric constant measurement at a temperature of 25° C. and a frequency of 1 MHz,
Regarding the washed toner obtained by washing the toner,
The content Z of the inorganic fine particles A in the washed toner is 0.2% by mass or more and 10.0% by mass or less with respect to the mass of the washed toner,
The silica fine particles B present in the washed toner have a primary particle number average particle diameter (D1) DB of 60 nm or more and 300 nm or less,
When the coverage of the inorganic fine particles A in the washed toner measured by an X-ray photoelectron spectrometer (ESCA) is X, and the coverage of the silica fine particles B is Y,
A toner wherein 0.10≤X/Y≤5.00. 2. The toner according to claim 1, wherein the inorganic fine particles A present in the washed toner have a primary particle number average particle diameter (D1) DA of 10 nm or more and 95 nm or less. 3. The toner according to claim 1, wherein the content Z of the inorganic fine particles A in the washed toner is 2.2% by mass or more and 10.0% by mass or less with respect to the mass of the washed toner. . 4. The toner according to any one of claims 1 to 3, wherein the inorganic fine particles A are inorganic fine particles having a perovskite structure. The toner according to any one of claims 1 to 4, wherein the inorganic fine particles A are strontium titanate particles. 6. The toner according to any one of claims 1 to 5, wherein the inorganic fine particles A and the silica fine particles B are thermally fixed to the surfaces of the toner particles. 1 to 1, wherein the content Z (% by mass) of the inorganic fine particles A in the washed toner and the content S (% by mass) of the silica fine particles B in the washed toner satisfy the following relationship: 7. The toner according to any one of 6.
Z>S The number average particle diameter (D1) DA of the primary particles of the inorganic fine particles A and the number average particle diameter (D1) DB of the primary particles of the silica fine particles B satisfy the following relationship: The toner according to any one of claims 1 to 3.
DA<DB

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