JP7013262B2 - toner - Google Patents

Description

The present invention relates to an electrograph, an image forming method for visualizing an electrostatic charge image, and a toner used in a toner jet.

In recent years, with the widespread use of image forming devices such as copiers and printers, the performance required for image forming devices is required to be higher in speed, longer in life, and higher in image quality. ..
As a means for achieving high image quality of an image forming apparatus, the particle size of toner is being reduced. When the particle size of the toner becomes smaller, the dot reproducibility and the fine line reproducibility are improved, but the fluidity and chargeability of the toner tend to be non-uniform.

In particular, when a large amount of images of the same pattern are printed, the toner in the printed portion and the toner in the non-printed portion on the developing sleeve tends to have non-uniform chargeability and fluidity. If different images are printed continuously while the chargeability and fluidity of the toner are non-uniform, the history of the previous image will be printed as a difference in image density (hereinafter referred to as sleeve ghost). In some cases.
For example, in Patent Document 1, silica having a number average particle size of 5 nm or more and 20 nm or less and silica having a number average particle size of 80 nm or more and 200 nm or less are added to the toner to control the chargeability and fluidity of the toner under a low temperature and low humidity environment. A technique capable of suppressing sleeve ghosting in silica is disclosed.

Further, when the charge distribution of the toner on the developing sleeve is broad, the toner having a low charge is accumulated in the developer, especially when used for a long period of time in a high temperature and high humidity environment, and the fine line reproducibility is achieved. There is also a problem that the dot reproducibility is deteriorated and the image quality of a fine image may be deteriorated.
On the other hand, when the particle size of the toner becomes smaller, it becomes difficult for the toner to be scraped off by the cleaning blade in the cleaning process, and it becomes easy for the toner to slip through the cleaning blade. So-called cleaning defects are likely to occur.
Conventionally, a method of adding strontium titanate to toner particles has been known as a countermeasure against poor cleaning. For example, Patent Document 2 describes a technique for improving cleaning defects by using a toner containing strontium titanate having an average number particle size of 80 nm or more and 220 nm or less and strontium titanate having an average number particle size of 300 nm or more and 3000 nm or less. Is disclosed.
Further, in Patent Document 3, a toner containing a composite inorganic fine powder containing strontium titanate having a half width of an X-ray diffraction peak at 32.20 deg is used to prevent cleaning defects. Techniques for improvement are disclosed.
Further, in Patent Document 4, transferability is improved by using a toner containing a composite oxide containing strontium titanate having a half width of an X-ray diffraction peak at 32.20 deg of 0.20 to 0.30 deg. The technology to be used is disclosed.

Japanese Unexamined Patent Publication No. 2016-110095 Japanese Unexamined Patent Publication No. 2006-195156 Japanese Patent No. 4799567 Japanese Patent No. 4979517

However, in the invention of Patent Document 1, further improvement is required for sleeve ghost in a high temperature and high humidity environment.
Further, the toner of Patent Document 2 has a certain effect in suppressing cleaning defects. However, as a result of studies by the present inventors, when a toner containing strontium titanate of 300 nm or more is continuously printed with a high printing rate in a low temperature and low humidity environment, strontium titanate and agglomerates of toner are formed in the developer. Is more likely to occur. As a result, it was found that due to the high abrasiveness of strontium titanate, the sleeve surface may be scraped and only that part may not be printed, so-called white streaks may occur, and further improvement is indispensable.
Further, in the toners of Patent Documents 3 and 4, further improvement is required for sleeve ghost.
The present invention has been made to solve the above-mentioned problems, and an object thereof is that sleeve ghost is less likely to occur even when used in a high temperature and high humidity environment or a low temperature and low humidity environment, and the present invention is long in a high temperature and high humidity environment. It is an object of the present invention to provide a toner having good fine line reproducibility and dot reproducibility even when it is used.
Further, it is to provide a toner capable of suppressing poor cleaning of the photoconductor and suppressing white streaks and sleeve ghosts even when used in a high temperature and high humidity environment or a low temperature and low humidity environment.

The first aspect of the present invention is a toner containing toner particles and strontium titanate particles .
The number average particle size of the primary particles of the strontium titanate particles is 10 nm or more and 95 nm or less.
The strontium titanate particles have a maximum peak (a) at a diffraction angle (2θ) of 32.000 deg or more and 32.40 deg or less in CuKα characteristic X-ray diffraction.
The half width of the maximum peak (a) is 0.23 deg or more and 0.50 deg or less.
The intensity (Ia) of the maximum peak (a) and the diffraction angle (2θ) in CuKα characteristic X-ray diffraction.
The maximum peak intensity (Ix) in the range of 24.00 deg or more and 28.00 deg or less satisfies the following formula (1).
(Ix) / (Ia) ≤ 0.010 ... (1)
The strontium titanate particles have the total content of strontium oxide and titanium oxide when the total amount of all oxides is 100% by mass, assuming that all the elements detected by fluorescent X-ray analysis are oxides. , 98.0% by mass or more,
In the powder fluidity analysis of the toner, the peripheral speed of the outermost edge of the propeller type blade is rotated at 100 mm / sec and vertically penetrated into the powder layer of the toner in the measuring container to obtain the powder layer. It is characterized in that the total Et of the rotational torque and the vertical load obtained when the measurement is started from a position 100 mm from the bottom surface and is advanced to a position 10 mm from the bottom surface is 100 mJ or more and 2000 mJ or less .

According to the first aspect of the present invention, sleeve ghost is less likely to occur even when used in a high temperature and high humidity environment or a low temperature and low humidity environment, and fine line reproducibility and fine line reproducibility and even when used in a high temperature and high humidity environment for a long period of time. It is possible to provide a toner having good dot reproducibility.
Further, according to the second aspect of the present invention, it is possible to provide a toner capable of suppressing poor cleaning of the photoconductor and suppressing white streaks and sleeve ghosts even when used in a high temperature and high humidity environment or a low temperature and low humidity environment. can.

An example of a pattern image for evaluating sleeve ghosts. An example of an image to evaluate a sleeve ghost.

In the present invention, the description of "○○ or more and XX or less" and "○○ to XX" indicating a numerical range means a numerical range including a lower limit and an upper limit which are end points, unless otherwise specified.
<First aspect>
Hereinafter, the first aspect of the present invention will be described in detail.
The first aspect is a toner containing toner particles and strontium titanate.
The average particle size of the number of primary particles of strontium titanate is 10 nm or more and 95 nm or less.
The strontium titanate has a maximum peak (a) at a diffraction angle (2θ) of 32.000 deg or more and 32.40 deg or less in CuKα characteristic X-ray diffraction.
The half width of the maximum peak (a) is 0.23 deg or more and 0.50 deg or less.
The intensity (Ia) of the maximum peak (a) and the diffraction angle (2θ) in CuKα characteristic X-ray diffraction.
The maximum peak intensity (Ix) in the range of 24.00 deg or more and 28.00 deg or less satisfies the following formula (1).
(Ix) / (Ia) ≤ 0.010 ... (1)
In the strontium titanate, the total content of strontium oxide and titanium oxide is calculated when the total amount of all oxides is 100% by mass, assuming that all the elements detected by fluorescent X-ray analysis are oxides. 98.0% by mass or more,
In the powder fluidity analysis of the toner, the peripheral speed of the outermost edge of the propeller type blade is rotated at 100 mm / sec and vertically penetrated into the powder layer of the toner in the measuring container to obtain the powder layer. It is characterized in that the total Et of the rotational torque and the vertical load obtained when the measurement is started from a position 100 mm from the bottom surface and is advanced to a position 10 mm from the bottom surface is 100 mJ or more and 2000 mJ or less.

The above toner is less likely to cause sleeve ghost even when used in a high temperature and high humidity environment or a low temperature and low humidity environment, and has good fine line reproducibility and dot reproducibility even when used for a long period of time in a high temperature and high humidity environment. be.
The reason why the above-mentioned configuration can obtain an unprecedented excellent effect is considered as follows.
In the present invention, strontium titanate has a maximum peak (a) at a diffraction angle (2θ) of 32.00 deg or more and 32.40 deg or less in CuKα characteristic X-ray diffraction, and the half width of the maximum peak (a) is large. It is characterized by being 0.23 deg or more and 0.50 deg or less. The maximum peak (a) is caused by the (1,1,0) plane peak of the crystal of strontium titanate.

As a result of diligent studies, the present inventors have found that it is very important to control the half width to 0.23 deg or more and 0.50 deg or less.
In general, the half width of the diffraction peak in X-ray diffraction is related to the crystallite diameter of strontium titanate. One grain of a primary particle is composed of a plurality of crystallites, and the crystallite diameter is the size of each crystallite constituting the primary particle.
In the present invention, the crystallites refer to individual crystal grains constituting the particles, and the crystallites gather to form particles. The crystallite size and particle size are irrelevant. When the crystallite diameter of strontium titanate is small, the half-value width becomes large, and when the crystallite diameter of strontium titanate is large, the half-value width becomes small.

The half width of the diffraction peak in the X-ray diffraction of strontium titanate of the present invention is 0.23 deg or more and 0.50 deg or less, which indicates that the crystallite diameter is smaller than that of the conventional strontium titanate.
As the crystallite diameter of strontium titanate becomes smaller, the grain boundaries (grain boundaries) of the crystallites existing in the primary particles increase. The grain boundaries are considered to be the points at which charges are trapped. Therefore, when the charge amount of the toner is small, the grain boundaries tend to trap the charge, so that the triboelectric charge amount of the toner rises quickly. On the other hand, since the charge of the toner easily leaks inside the crystallite of strontium titanate, if the toner is overcharged and exceeds the charge amount that the crystal grain boundary can trap, the charge passes through the inside of the crystallite. It is considered that the excessive charge of the toner can be suppressed.

That is, by controlling the half width to 0.23 deg or more and 0.50 deg or less, it is possible to obtain an effect of accelerating the rise of charging of the toner and suppressing overcharging of the toner, which was not possible with conventional strontium titanate. I was able to. As a result, even when a large number of images of the same pattern are printed, it is possible to keep the chargeability of the toner in the printed portion and the non-printed portion on the developing sleeve uniform. Therefore, it is considered that the effect of suppressing sleeve ghost is dramatically enhanced even when used in a high temperature and high humidity environment or a low temperature and low humidity environment.

Further, when the effect of accelerating the rise of charge of the toner on the developing sleeve and suppressing the overcharge becomes good, the charge amount distribution of the toner becomes sharper. When the toner charge distribution is broad, especially when used for a long time in a high temperature and high humidity environment, toner with a low charge is accumulated in the developing device, and the fine line reproducibility and dot reproducibility are deteriorated. The image quality of the image may deteriorate.
In the present invention, since the effect of accelerating the rise of charge of the toner and suppressing the excessive charge is good, the charge amount distribution of the toner becomes sharp, and even when the toner is used for a long period of time in a high temperature and high humidity environment. It is possible to provide a toner having good fine line reproducibility and dot reproducibility.

In the present invention, it is important that the half width of the diffraction peak in the X-ray diffraction of strontium titanate is 0.23 deg or more and 0.50 deg or less, preferably 0.25 deg or more and 0.45 deg or less, and more preferably 0. It is .28 deg or more and 0.40 deg or less. Within the above range, the sleeve ghost is better even when used in a high temperature and high humidity environment or a low temperature and low humidity environment, and even when used in a high temperature and high humidity environment for a long period of time, the fine line reproducibility of the toner and the fine line reproducibility and Good dot reproducibility.

In the present invention, the intensity (Ia) of the maximum peak (a) and the maximum peak intensity (Ix) in the range of 24.00 deg or more and 28.00 deg or less of the diffraction angle (2θ) in CuKα characteristic X-ray diffraction are as follows. It is important to satisfy (1).
(Ix) / (Ia) ≤ 0.010 ... (1)
(Ix) represents the peak of SrCO ₃ and TiO ₂ derived from the raw material of strontium titanate.

If (Ix) / (Ia) does not satisfy the formula (1), it means that the purity of strontium titanate is low. For example, SrCO ₃ and TiO ₂ derived from the raw material of strontium titanate.
If is left as an impurity, these maximum peak intensities (Ix) become large and do not satisfy the formula (1). In this case, impurities are likely to be localized at the grain boundaries, charges are not trapped at the grain boundaries, and leaks are likely to occur. Therefore, the rise of charging is delayed.
On the other hand, by satisfying the formula (1), the purity of strontium titanate is high and there are few impurities localized at the grain boundaries, so that the charge is easily trapped at the grain boundaries and the rise of the charge is accelerated. As a result, sleeve ghosts are less likely to occur even when used in a high temperature and high humidity environment, and fine line reproducibility and dot reproducibility are improved even when used in a high temperature and high humidity environment for a long period of time.

It is important that the formula (1) has (Ix) / (Ia) ≤ 0.010, preferably (Ix) / (Ia) ≤ 0.008. It is preferable that there is no (Ix) peak derived from impurities.
(Ix) / (Ia) can be controlled by the mixing ratio of the titanium raw material and the strontium raw material, the reaction temperature, and the reaction time. Further, it can be controlled by pickling the strontium titanate slurry after the reaction.

In the present invention, strontium titanate has a content of strontium oxide and titanium oxide when all the elements detected by fluorescent X-ray analysis are regarded as oxides and the total amount of all oxides is 100% by mass. It is important that it is 98.0% by mass or more.
When the content is less than 98.0% by mass, it means that impurities other than strontium titanate are abundant inside the crystal. When there are many impurities inside the crystal of strontium titanate, the impurities distort the crystal, and the half-value width becomes large due to the effect. In this case, although the half width can be increased, it is difficult to control the crystallite diameter to be small, so that the grain boundaries are reduced and the charge is likely to leak. Therefore, the rise of charge is delayed.
By setting the content of strontium oxide and titanium oxide to 98.0% by mass or more, the crystallite diameter of the strontium titanate particles can be controlled to be small, which has the effect of accelerating the rise of charging and suppressing overcharging. Can be made better. As a result, sleeve ghost is less likely to occur even when used in a high temperature and high humidity environment or a low temperature and low humidity environment, and fine line reproducibility and dot reproducibility are good even when used for a long period of time in a high temperature and high humidity environment. Become.
The content of strontium oxide and titanium oxide is preferably 98.2% by mass or more. The upper limit is not particularly limited, but is preferably 100% by mass or less. The content can be controlled by purifying the titanium raw material and reducing impurities.

The number average particle size of the primary particles of strontium titanate in the present invention is 10 nm or more and 95 nm or less. When the number average particle size of the primary particles is 10 nm or more, strontium titanate is effectively finely dispersed on the surface of the toner particles, and overcharging of the toner is suppressed. When the number average particle size of the primary particles is 95 nm or less, sufficient adhesion of strontium titanate to the toner particles can be obtained, the rise of the charged amount of the toner is accelerated, and the overcharge of the toner is effective. Can be suppressed. Therefore, the sleeve ghost is better even when used in a high temperature and high humidity environment or a low temperature and low humidity environment, and fine line reproducibility and dot reproducibility are good even when used for a long period of time in a high temperature and high humidity environment. Toner can be provided.
The average particle size of the number of primary particles of strontium titanate is preferably 10 nm or more and 70 nm or less, and more preferably 10 nm or more and 50 nm or less. The number average particle size of the primary particles of strontium titanate can be controlled by the concentrations, reaction temperature and reaction time of the titanium raw material and the strontium raw material.

In the powder fluidity analysis, the toner of the present invention vertically penetrates into the powder layer of the toner in the measuring container while rotating the peripheral speed of the outermost edge of the propeller type blade at 100 mm / sec, and the powder is the powder. The measurement is started from a position 100 mm from the bottom surface of the body layer, and the total Et of the rotational torque and the vertical load obtained when the measurement is started to the position 10 mm from the bottom surface is 100 mJ or more and 2000 mJ or less.
The measurement condition of Et indicates the flow state of the toner in the vicinity of the developing sleeve where the toner is rubbed at high speed in the developing device. In particular, it shows the flow state immediately before the toner supported on the surface of the developing sleeve rushes into the facing portion between the developer layer thickness regulating member and the developing sleeve.

By controlling Et to 100 mJ or more and 2000 mJ or less, the force applied to the toner from the developer layer thickness regulating member can be controlled to be constant, so that the toner layer thickness on the developing sleeve can be made uniform. Therefore, even when a large number of images of the same pattern are printed, the chargeability and fluidity of the toner in the printed portion and the non-printed portion on the developing sleeve can be made uniform. As a result, sleeve ghost, fine line reproducibility, and dot reproducibility are improved.

The Et is preferably 200 mJ or more and 1000 mJ or less, and more preferably 200 mJ or more and 500 mJ or less.
In order to control Et, the temperature inside the mixer tank when mixing the toner particles and the external additive is -20 at the difference between the glass transition temperature Tg of the toner particles and the temperature inside the tank (Tg-temperature inside the tank). It is preferably ℃ or more and -10 ℃ or less. As a result, the external additive can be easily adhered to the surface of the toner particles, so that the Et of the toner can be easily controlled.

The content of strontium titanate is preferably 0.05 parts by mass or more and 2.0 parts by mass or less, and more preferably 0.1 parts by mass or more and 1.5 parts by mass or less with respect to 100 parts by mass of the toner particles. preferable.
Within the above range, the effect of suppressing overcharging of the toner and the effect of accelerating the rise of the triboelectric charge amount can be easily obtained. Therefore, sleeve ghost is less likely to occur even when used in a high temperature and high humidity environment or a low temperature and low humidity environment, and fine line reproducibility and dot reproducibility are improved even when used for a long period of time in a high temperature and high humidity environment. ..

The strontium titanate of the present invention preferably has a water adsorption amount of 1 mg / g or more and 40 mg / g or less at a temperature of 30 ° C. and a humidity of 80% RH, and more preferably 1 mg / g or more and 25 mg / g or less. It is more preferably 1 mg / g or more and 20 mg / g or less.
By controlling the amount of water adsorbed within the above range, the influence of the decrease in the amount of charge can be reduced in a high temperature and high humidity environment, so that the rise of charge can be accelerated and the amount of charge can be made uniform. .. As a result, sleeve ghosts are less likely to occur even when used in a high temperature and high humidity environment, and fine line reproducibility and dot reproducibility are improved even when used in a high temperature and high humidity environment for a long period of time.

<Second aspect>
A second aspect of the present invention is a toner containing toner particles, inorganic fine particles A and inorganic fine particles B.
The weight average particle size (D4) of the toner is 3.0 μm or more and 10.0 μm or less.
The inorganic fine particles A and the inorganic fine particles B are strontium titanate.
The number average particle size of the primary particles of the inorganic fine particles A is 10 nm or more and 95 nm or less.
The inorganic fine particles A have a maximum peak (a) at a diffraction angle (2θ) of 32.00 deg or more and 32.40 deg or less in CuKα characteristic X-ray diffraction.
The half width of the maximum peak (a) is 0.23 deg or more and 0.50 deg or less.
The inorganic fine particles A have a water adsorption amount of 1 mg / g or more and 40 mg / g or less at a relative humidity of 80% in a water adsorption isotherm at 30 ° C.
The number average particle size of the primary particles of the inorganic fine particles B is 500 nm or more and 2000 nm or less.

The toner in the second aspect contains the inorganic fine particles A and the inorganic fine particles B, and the inorganic fine particles A and the inorganic fine particles B are strontium titanate.
The number average particle size of the primary particles of the inorganic fine particles A is 10 nm or more and 95 nm or less. When the size is 10 nm or more, the inorganic fine particles A are effectively finely dispersed on the surface of the toner particles, and overcharging of the toner and the inorganic fine particles B is suppressed. On the other hand, when the size is 95 nm or less, the adhesive force required for the inorganic fine particles A to be present on the toner surface can be sufficiently obtained, and the effect of accelerating the rise of the charged amount of the toner and the effect of suppressing overcharging can be obtained. It can be obtained effectively. Therefore, the generation of sleeve ghosts and white streaks can be suppressed even when used in a high temperature and high humidity environment or a low temperature and low humidity environment.
The average particle size of the number of primary particles of the inorganic fine particles A is preferably 10 nm or more and 70 nm or less, and more preferably 10 nm or more and 50 nm or less.

Further, the inorganic fine particles A have a maximum peak (a) at a diffraction angle (2θ) of 32.00 deg or more and 32.40 deg or less in CuKα characteristic X-ray diffraction, and the half width of the maximum peak (a) is 0. It is 23 deg or more and 0.50 deg or less. It is preferably 0.25 deg or more and 0.45 deg or less, and more preferably 0.28 deg or more and 0.40 deg or less. Such a feature is the same as that of strontium titanate in the first aspect, and by using the inorganic fine particles A, the effect of accelerating the rise of charging of the toner on the developing sleeve and suppressing overcharging can be obtained. ..

On the other hand, the number average particle size of the primary particles of the inorganic fine particles B is 500 nm or more and 2000 nm or less. Cleaning defects can be suppressed by such inorganic fine particles B.
The toner remaining on the photoconductor after the transfer process is scraped off by a cleaning means such as a cleaning blade in contact with the photoconductor, but at this time, the phenomenon that the toner and the external additive partially slip through the cleaning blade is a cleaning defect. be. As a result, the toner or the external additive that has slipped through may contaminate the charging member, or the toner that has slipped through may become vertical streaks and cause image defects.
The number average particle size of the primary particles of the inorganic fine particles B is preferably 600 nm or more and 1500 nm or less, and more preferably 600 nm or more and 1000 nm or less.

When the toner using the inorganic fine particles B is used, the inorganic fine particles B scraped off by the cleaning blade accumulate at the contact portion between the cleaning blade and the photoconductor, and a blocking layer due to the inorganic fine particles B can be formed. It is thought that it has the effect of suppressing the slip-through of toner and external additives.
However, it was found that when images with a high printing rate were continuously printed, agglomerates of toner and inorganic fine particles B were generated in the developing device, the sleeve was scraped, and white streaks were generated. Further, it was found that the effect of suppressing the cleaning failure due to the formation of the blocking layer, which is a function of the inorganic fine particles B, is difficult to obtain because the inorganic fine particles B become agglomerates.
Therefore, as a result of diligent studies by the present inventors, it has been found that by using the inorganic fine particles A at the same time, it is possible to suppress the generation of agglomerates between the toner and the inorganic fine particles B, and it is possible to suppress white streaks while suppressing cleaning defects. rice field.

The reason why the above effect can be obtained can be inferred as follows. It is known that the inorganic fine particles B, which are strontium titanate having a diameter of 500 nm or more and 2000 nm or less, have an effect of imparting a charge to the toner. In particular, when images with a high printing rate are continuously printed, it is considered that the rise of charging of the toner is delayed and the charging effect of the inorganic fine particles B is increased. At this time, since the inorganic fine particles B are charged in the opposite polarity to the toner, it is considered that an electrostatic adhesive force acts strongly between the toner and the inorganic fine particles B, and agglomerates are generated, which causes white streaks. Further, when the inorganic fine particles B are present as agglomerates with the toner, it is considered that the function of forming the blocking layer in the cleaning blade portion is also impaired, which causes a cleaning failure.
On the other hand, as described above, the inorganic fine particles A are considered to be able to obtain the effect of suppressing overcharging of the toner and the inorganic fine particles B. It is considered that the generation of agglomerates could be suppressed by alleviating the electrostatic adhesive force generated between the toner and the inorganic fine particles B due to the effect of the inorganic fine particles A. As a result, it is considered that poor cleaning and white streaks could be suppressed.

In the second aspect, it is important that the weight average particle size (D4) of the toner is 3.0 μm or more and 10.0 μm or less. Within the above range, the inorganic fine particles A can be effectively finely dispersed on the toner surface.
The weight average particle size (D4) is preferably 4.0 μm or more and 9.0 μm or less, more preferably 4.5 μm or more and 8.5 μm or less, and further preferably 5.0 μm or more and 8.0 μm or less. ..

Further, it is important that the amount of water adsorbed in the inorganic fine particles A at a relative humidity of 80% is 1 mg / g or more and 40 mg / g or less in the water adsorption isotherm at 30 ° C. By controlling the amount of water adsorbed within the above range, the influence of water on charge control can be suppressed to a small extent, and the rise of triboelectric charge can be accelerated, and the effect of suppressing excessive charge can be effectively obtained, especially in a high temperature and high humidity environment. It is possible to suppress the occurrence of sleeve ghosts and white streaks.
The amount of water adsorbed is more preferably 1 mg / g or more and 25 mg / g or less, and further preferably 1 mg / g or more and 20 mg / g or less. As a result, sleeve ghosts are less likely to occur even when used in a high temperature and high humidity environment. The amount of water adsorbed can be controlled by surface-treating the inorganic fine particles A with a hydrophobic treatment agent.

The content of the inorganic fine particles A is preferably 0.05 parts by mass or more and 2.0 parts by mass or less, and more preferably 0.1 parts by mass or more and 1.5 parts by mass or less with respect to 100 parts by mass of the toner particles. preferable.
By setting the content of the inorganic fine particles A in the above range, it is easy to obtain the effect of suppressing excessive charge of the toner and the effect of accelerating the rise of charge. Therefore, even when the toner is used in a high temperature and high humidity environment or a low temperature and low humidity environment. , Sleeve ghost and white streaks are good.
Further, from the viewpoint of suppressing the generation of agglomerates, the mass ratio [A / B] of the inorganic fine particles A and the inorganic fine particles B is preferably 1.0 / 1.0 to 1.0 / 20.0, preferably 1.0. /3.0 to 1.0 / 18.0 is more preferable.

The inorganic fine particles A have a maximum peak (a) at a diffraction angle (2θ) of 32.000 deg or more and 32.40 or less in CuKα characteristic X-ray diffraction, and the intensity (Ia) of the maximum peak (a) and C.
uKα characteristic The diffraction angle (2θ) in X-ray diffraction is 24.00 deg or more and 28.00 deg.
It is preferable that the intensity (Ix) of the maximum peak in the following range satisfies the following formula.
(Ix) / (Ia) ≤ 0.010
It is more preferable that (Ix) / (Ia) is 0.008 or less.

The characteristics are the same as in the first aspect. By satisfying the above formula, impurities localized at the grain boundaries are reduced, the toner charge rises quickly, the overcharge suppression effect can be easily obtained, and cleaning defects, sleeve ghosts, and white streaks are less likely to occur.

In the inorganic fine particles A, the total content of strontium oxide and titanium oxide is 98. When the total amount of all oxides is 100% by mass, assuming that all the elements detected by fluorescent X-ray analysis are oxides. It is preferably 0% by mass or more, and more preferably 98.2% by mass or more.
The characteristics are the same as in the first aspect. By satisfying the above range, the rise of charging becomes faster, and it becomes easier to suppress overcharging. As a result, poor cleaning, sleeve ghosts, and white streaks are less likely to occur.

Next, preferred embodiments and the like in the first aspect and the second aspect will be described.
The strontium titanate or the inorganic fine particles A are preferably surface-treated for the purpose of hydrophobizing and controlling triboelectricity, if necessary. That is, examples of the treatment agent include unmodified silicone varnish, various modified silicone varnishes, unmodified silicone oil, various modified silicone oils, silane coupling agents, silane compounds having functional groups, and other organosilicon compounds. Be done. Various treatment agents may be used in combination. Of these, it is particularly preferable that the treatment is performed with a silane coupling agent. That is, it is preferable that the strontium titanate or the inorganic fine particles A are surface-treated fine particles with a silane coupling agent.

Examples of the silane coupling agent include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, β- (3,4 epoxycyclohexyl) ethyltrimethoxysilane, and γ-glycidoxypropyltrimethoxy. Silane, γ-glycidoxypropylmethyldiethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, methyltrimethoxy Silane, dimethyldimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, diphenyldiethoxysilane, n-butyltrimethoxysilane, isobutyltrimethoxysilane, trimethylmethoxysilane , N-hexyltrimethoxysilane, n-octyltrimethoxysilane, n-octyltrimethoxysilane, n-decyltrimethoxysilane, hydroxypropyltrimethoxysilane, n-hexadecyltrimethoxysilane, n-octadecyltrimethoxysilane, Examples thereof include trifluoropropyltrimethoxysilane and hydrolysates thereof.

Of these, n-octyltriethoxysilane, isobutyltrimethoxysilane, and trifluoropropyltrimethoxysilane are preferable, and isobutyltrimethoxysilane is more preferable. In addition, these treatment agents may be used alone or in combination of two or more.
The surface treatment can chemically modify the surface of the strontium titanate particles, but does not affect the crystal structure of the strontium titanate particles. That is, the surface treatment does not affect the half width of the maximum peak (a) of strontium titanate. Therefore, in the present invention, in order to measure the impurity element that affects the crystal structure, the fluorescent X-ray measurement of strontium titanate or the inorganic fine particles A is performed before the surface treatment.

In the first aspect and the second aspect, the specific surface area of strontium titanate or inorganic fine particles A by the BET method by nitrogen adsorption after surface treatment is preferably 10 m ² / g or more and 200 m ² / g or less, preferably 10 m. It is more preferably ² / g or more and 100 m ² / g or less. By controlling the BET specific surface area within the above range, the inorganic fine particles can be easily finely dispersed evenly on the toner surface, so that the effect of suppressing overcharging of the toner and the effect of accelerating the rise of charging can be fully exerted. can.

The preparation method of strontium titanate or inorganic fine particles A is not particularly limited, but is produced by, for example, the following method.
For example, strontium nitrate, strontium chloride, etc. are added to a dispersion of titania sol obtained by adjusting the pH of a hydroxide-containing titanium slurry obtained by hydrolyzing an aqueous solution of titanyl sulfate, and then heated to the reaction temperature. It can be synthesized by adding an alkaline aqueous solution. The reaction temperature is preferably 60 to 100 ° C.

In order to control the half width of the maximum peak (a), it is preferable that the time required for adding the alkaline aqueous solution is 60 minutes or less in the step of adding the alkaline aqueous solution. By setting the addition rate of the alkaline aqueous solution to 60 minutes or less, particles having a small crystallite diameter can be obtained.
Further, in the step of adding the alkaline aqueous solution, it is preferable to add while applying ultrasonic vibration in order to control the half width. By applying ultrasonic vibration in the reaction step, the precipitation rate of crystals is increased, and particles having a small crystallite diameter can be obtained.

Further, it is preferable to rapidly cool the aqueous solution obtained by adding an alkaline aqueous solution to control the half width. Examples of the method of quenching include a method of adding pure water cooled to 10 ° C. or lower until a desired temperature is reached. By quenching, it is possible to prevent the crystallite diameter from becoming large in the cooling step.
On the other hand, as a method of controlling the half width, a strong processing method (a method of mechanically applying a strong force to the inorganic fine particles) may be used. As the strong machining, a ball mill method, high-pressure twisting, drop weight machining, particle impact, air-type shot peening, or the like can be used.

The toner of the present invention preferably contains silica fine powder in addition to strontium titanate as inorganic fine particles in order to improve charge stability, developability, fluidity, and durability. The specific surface area of the silica fine powder by the BET method by nitrogen adsorption is preferably 30 m ² / g or more and 500 m ² / g or less, and more preferably 50 m ² / g or more and 400 m ² / g or less. The content of the silica fine powder is preferably 0.01 parts by mass or more and 8.0 parts by mass or less, and more preferably 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.
The silica fine powder has an unmodified silicone varnish, various modified silicone varnishes, unmodified silicone oils, various modified silicone oils, silane coupling agents, and functional groups for the purpose of hydrophobization and friction charge control, if necessary. It is also preferable that the surface is treated with a treatment agent such as a silane compound or another organosilicon compound, or in combination with various treatment agents.

Other external additives may be added to the toner, if necessary. Examples of such an external additive include resin fine particles that act as a charging aid, a conductivity-imparting agent, a fluidity-imparting agent, a caking inhibitor, a mold release agent at the time of fixing a thermal roller, a lubricant, an abrasive, and the like. Examples include inorganic fine particles. Examples of the lubricant include polyvinylidene fluoride powder, zinc stearate powder, and polyvinylidene fluoride powder. Examples of the abrasive include cerium oxide powder and silicon carbide powder.

The toner particles may contain a binder resin. Examples of the binder resin include the following.
Styline resin, styrene copolymer resin, polyester resin, polyol resin, polyvinyl chloride resin, phenol resin, natural resin modified phenol resin, natural resin modified maleic acid resin, acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin, Polyurethane resin, polyamide resin, furan resin, epoxy resin, xylene resin, polyvinyl butyral, terpene resin, kumaron inden resin, petroleum resin. Examples of the resin preferably used include a styrene-based copolymer resin, a polyester resin, and a hybrid resin in which the polyester resin and the styrene-based copolymer resin are mixed or partially reacted with each other. More preferably, the binder resin includes a polyester resin.

The glass transition temperature (Tg) of the binder resin is preferably 45 ° C. or higher from the viewpoint of storage stability. Further, from the viewpoint of low temperature fixability, Tg is preferably 75 ° C. or lower, more preferably 70 ° C. or lower. The method for measuring the glass transition temperature will be described later.

A mold release agent (wax) may be used to impart mold releasability to the toner.
Examples of waxes include: Fatty acid hydrocarbon waxes such as low molecular weight polyethylene, low molecular weight polypropylene, olefin copolymers, microcrystallin wax, paraffin wax, Fisher Tropsch wax; oxidized wax of aliphatic hydrocarbon wax such as polyethylene oxide wax; carnauba wax , Waxes mainly composed of fatty acid esters such as behenyl behenate and montanoic acid ester wax; and partially or completely deoxidized fatty acid esters such as deoxidized carnauba wax.
In addition, saturated linear fatty acids such as palmitic acid, stearic acid, and montanic acid; unsaturated fatty acids such as brushzic acid, eleostearic acid, and varinaric acid; , Saturated alcohols such as melisyl alcohol; Polyhydric alcohols such as sorbitol; Fatty acid amides such as linoleic acid amide, oleic acid amide, lauric acid amide; Methylene bisstearic acid amide, ethylene biscapric acid amide, ethylene bislaurin Saturated fatty acid bisamides such as acid amides and hexamethylene bisstearic acid amides; ethylene bisoleic acid amides, hexamethylene bisoleic acid amides, N, N'-diorail adipic acid amides, N, N'-diorail sevacinic acid amides. Unsaturated fatty acid amides such as; aromatic bisamides such as m-xylene bisstearic acid amide, N, N'-distearylisophthalic acid amide; fats such as calcium stearate, calcium laurate, zinc stearate, magnesium stearate. Group metal salts (generally referred to as metal soap); waxes grafted on aliphatic hydrocarbon wax using vinyl copolymer monomer such as styrene and acrylic acid; fatty acids such as behenic acid monoglyceride and many Partial esterified products of fatty alcohols; methyl ester compounds having a hydroxyl group obtained by hydrogenation of vegetable fats and oils and the like can be mentioned.

The wax particularly preferably used in the present invention is an aliphatic hydrocarbon-based wax. For example, low molecular weight hydrocarbons obtained by radically polymerizing alkylene at high pressure or polymerized with Cheegler catalyst or metallocene catalyst under low pressure; Fischer-Tropschwax synthesized from coal or syngas; obtained by thermal decomposition of high molecular weight olefin polymer. Olefin polymer; synthetic hydrocarbon wax obtained from the distillation residue of hydrocarbon obtained by the age method from synthetic gas containing carbon monoxide and hydrogen, or synthetic hydrocarbon wax obtained by hydrogenating these is preferable.
Further, those obtained by separating the hydrocarbon wax by the press sweating method, the solvent method, the use of vacuum distillation or the fractional crystallization method are more preferably used. In particular, a wax synthesized by a method not based on the polymerization of alkylene is preferable from the viewpoint of its molecular weight distribution.
The timing of adding the wax may be at the time of manufacturing the toner or at the time of manufacturing the binder resin. In addition, one type of these waxes may be used alone, or two or more types may be used in combination. The wax is preferably added in an amount of 1 part by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the binder resin.

The toner of the present invention can be used as any of a magnetic one-component toner, a non-magnetic one-component toner, and a non-magnetic two-component toner.
When used as a magnetic one-component toner, magnetic iron oxide particles are preferably used as the colorant. Examples of the magnetic iron oxide particles contained in the magnetic one-component toner include magnetic iron oxide containing magnetite, maghemite, and ferrite, and magnetic iron oxide containing other metal oxides; metals such as Fe, Co, and Ni, or Alloys of these metals with metals such as Al, Co, Cu, Pb, Mg, Ni, Sn, Zn, Sb, Be, Bi, Cd, Ca, Mn, Se, Ti, W, V, and these. Examples include mixtures. The content of the magnetic iron oxide particles 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.

Examples of the colorant when used as a non-magnetic one-component toner and a non-magnetic two-component toner include the following.
As the black pigment, carbon black such as furnace black, channel black, acetylene black, thermal black, and lamp black is used, and magnetic powder such as magnetite and ferrite is also used.
As a suitable colorant for yellow color, a pigment or a dye can be used. As the 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 can be mentioned. As the dye, C.I. I. Examples thereof include Solvent Yellow 19, 44, 77, 79, 81, 82, 93, 98, 103, 104, 112, 162 and the like. These may be used alone or in combination of two or more.

As a suitable colorant for cyan color, a pigment or a dye can be used. As the pigment, C.I. I. Pigment Blue 1, 7, 15, 15; 1, 15; 2, 15; 3, 15; 4, 16, 17, 60, 62, 66, etc., C.I. I. Bat Blue 6, C.I. I. Acid blue 45 can be mentioned. As the dye, C.I. I. Solvent blue 25, 36, 60, 70, 93, 95 and the like can be mentioned. These may be used alone or in combination of two or more.
As a colorant suitable for magenta color, a pigment or a dye can be used. As the 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; 1,58,60, 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, etc., C.I. I. Pigment Violet 19; C.I. I. Bat reds 1, 2, 10, 13, 15, 23, 29, 35 can be mentioned.
As the magenta 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, etc., C.I. I. Disperse thread 9, C.I. I. Solvent Violet 8, 13, 14, 21, 27, etc., 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, etc., C.I. I. Examples thereof include basic dyes such as Basic Violet 1,3,7,10,14,15,21,25,26,27,28. These may be used alone or in combination of two or more.
The content of the colorant is preferably 1 part by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the binder resin.

A charge control agent may be used as the toner. As the charge control agent, known ones can be used, for example, an azo-based iron compound, an azo-based chromium compound, an azo-based manganese compound, an azo-based cobalt compound, an azo-based zirconium compound, a carboxylic acid derivative chromium compound, and a carboxylic acid. Examples thereof include a zinc compound as a derivative, an aluminum compound as a carboxylic acid derivative, and a zirconium compound as a carboxylic acid derivative.
The carboxylic acid derivative is preferably an aromatic hydroxycarboxylic acid. Further, a charge control resin can also be used. When a charge control agent or a charge control resin is used, it is preferable to use 0.1 part by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the binder resin.

The toner may be mixed with a carrier and used as a two-component developer. As the carrier, a normal carrier such as ferrite or magnetite or a resin-coated carrier can be used. Further, a binder type carrier core in which magnetic powder is dispersed in a resin can also be used.

The resin coat carrier is composed of carrier core particles and a coating material which is a resin that coats (coats) the surface of the carrier core particles. Resins used for the coating material include styrene-acrylic resins such as styrene-acrylic acid ester copolymers and styrene-methacrylate copolymers; acrylics such as acrylic acid ester copolymers and methacrylate ester copolymers. Examples thereof include fluorine-containing resins such as polytetrafluoroethylene, monochlorotrifluoroethylene polymer, and polyvinylidene fluoride; silicone resins; polyester resins; polyamide resins; polyvinyl butyral; aminoacrylate resins. Other examples include iomonomer resin and polyphenylene sulfide resin. These resins can be used alone or in combination of two or more.

The method for producing the toner is not particularly limited, and known methods such as a pulverization method, a suspension polymerization method, and an emulsion aggregation method can be used. The method for producing toner will be described below by taking the pulverization method as an example, but the method is not limited thereto.
For example, the binder resin and, if necessary, the colorant and other additives are sufficiently mixed by a mixer such as a Henschel mixer or a ball mill and then heat-kneaded such as a heating roll, a kneader and an extruder. It is melt-kneaded using a machine, cooled and solidified, then pulverized and classified to obtain toner particles. Further, the toner particles are sufficiently mixed with the strontium titanate or the inorganic fine particles A and B, and if necessary, silica fine powder and the like with a mixer such as a Henshell mixer to obtain a toner.

Examples of the mixer include the following. Henschel Mixer (Mitsui Mining Co., Ltd.); Super Mixer (Kawata Co., Ltd.); Ribocorn (Okawara Seisakusho Co., Ltd.); Nowter Mixer, Turbulizer, Cyclomix (Hosokawa Micron Co., Ltd.); Spiral Pin Mixer (Pacific Kiko Co., Ltd.) Ladyge mixer (manufactured by Matsubo).
Examples of the kneading machine include the following. KRC Kneader (manufactured by Kurimoto Iron Works); Bus Co Kneader (manufactured by Buss); TEM type extruder (manufactured by Toshiba Machinery Co., Ltd.); TEX twin-screw kneader machine (manufactured by Japan Steel Works Co., Ltd.); PCM kneader (Ikegai) Iron Works); Three roll mill, mixing roll mill, kneader (Inoue Mfg. Co., Ltd.); Kneedex (Mitsui Mine Co., Ltd.); MS type pressurized kneader, Nider Ruder (Moriyama Mfg. Co., Ltd.); Banbury mixer (Kobe Steel) Made by Tokorosha).

Examples of the crusher include the following. Counter jet mill, micron jet, innomizer (manufactured by Hosokawa Micron); IDS type mill, PJM jet crusher (manufactured by Nippon Pneumatic Industries); cross jet mill (manufactured by Kurimoto Iron Works); Ulmax (manufactured by Nippon Soda Engineering Co., Ltd.) ); SK Jet O Mill (manufactured by Seishin Enterprise Co., Ltd.); Cryptron (manufactured by EarthTechnica Co., Ltd.); Turbo Mill (manufactured by Turbo Industry Co., Ltd.); Super Rotor (manufactured by Nisshin Engineering Co., Ltd.).
Examples of the classifier include the following. Classifier, Micron Classifier, Spedic Classifier (manufactured by Seishin Enterprise Co., Ltd.); Turbo Classifier (manufactured by Nisshin Engineering Co., Ltd.); Micron Separator, Turboplex (ATP), TSP Separator, TTSP Separator (manufactured by Hosokawa Micron); Elbow Jet (manufactured by Nittetsu Mining Co., Ltd.), Dispersion Separator (manufactured by Nippon Pneumatic Industries Co., Ltd.); YM Microcut (manufactured by Yasukawa Shoji Co., Ltd.).
Examples of the sieving device used for sieving coarse particles include the following.
Ultra Sonic (manufactured by Koei Sangyo Co., Ltd.); Resonance Sheave, Gyro Shifter (manufactured by Tokuju Kosakusho); Vibra Sonic System (manufactured by Dalton); Soniclean (manufactured by Shinto Kogyo); Turbo Cleaner (manufactured by Turbo Kogyo); Micro shifter (manufactured by Makino Sangyo Co., Ltd.); Circular vibration sieve.

Next, a method for measuring each physical property according to the present invention will be described.
<X-ray diffraction measurement>
The measurement is performed using MiniFlex 600 (manufactured by Rigaku Co., Ltd.) under the following conditions.
The measurement sample is placed on a non-reflective sample plate (manufactured by Rigaku) that does not have a diffraction peak within the measurement range while lightly pressing the inorganic fine particles (strontium titanate) as powder so as to be flat. When it becomes flat, set it in the device together with the sample plate.
[Measurement conditions for X-ray diffraction]
Tube: Cu
Parallel beam optical system voltage: 40 kV
Current: 15mA
Starting angle: 3 °
End angle: 60 °
Sampling width: 0.02 °
Scan speed: 10.00 ° / min
Divergence slit: 0.625 deg
Scattering slit: 8.0 mm
Light receiving slit: 13.0 mm (Open)
The half-value width and peak intensity of the obtained X-ray diffraction peak are calculated using the analysis software "PDXL" manufactured by Rigaku.

<Fluorescent X-ray measurement>
The fluorescent X-ray measurement of the inorganic fine particles (strontium titanate or the inorganic fine particles A) is performed before the surface treatment when the surface treatment is performed with a silane coupling agent or the like.
The elements from Na to U in the inorganic fine particles are directly measured in a He atmosphere using a wavelength dispersive fluorescent X-ray analyzer Axios advanced (manufactured by Spectris). Using the liquid sample cup attached to the device, put a PP (polypropylene) film on the bottom surface, put a sufficient amount of the sample, form a layer with a uniform thickness on the bottom surface, and cover it. The output is measured under the condition of 2.4 kW. The FP (fundamental parameter) method is used for the analysis. At that time, it is assumed that all the detected elements are oxides, and their total mass is 100% by mass. The content (% by mass) of strontium oxide (SrO) and titanium oxide (TIO ₂ ) with respect to the total mass is determined as an oxide conversion value by software UniQuant5 (ver. 5.49) (manufactured by Spectris).

<Measurement of average particle size of primary particles of inorganic fine particles>
The number average particle size of the primary particles of the inorganic fine particles (strontium titanate, inorganic fine particles A and B) was observed with a transmission electron microscope "H-800" (manufactured by Hitachi, Ltd.), and in a field magnified up to 2 million times. , The major axis of 100 primary particles is measured to obtain the number average particle size.

<Measurement of water adsorption amount>
The water adsorption amount of the inorganic fine particles (strontium titanate or inorganic fine particles A) was measured using a "high-precision steam adsorption amount measuring device BELSORP-aqua3" (Nippon Bell Co., Ltd.).
The "high-precision steam adsorption amount measuring device BELSORP-aqua3" reaches a solid-gas equilibrium under the condition that only the target gas (water in the case of the present invention) is present, and the solid mass and vapor pressure at this time are measured. Measure.
First, about 0.5 g of a sample is introduced into a sample cell and degassed at room temperature of 100 Pa or less for 24 hours. After the degassing was completed, the sample mass was precisely weighed, set in the main body of the apparatus, and measured under the following conditions.・ Air constant temperature bath temperature: 80.0 ℃
・ Adsorption temperature: 30.0 ° C
・ Adsorbent name: H ₂ O
Equilibrium time: 500 sec
・ Waiting for temperature: 60min
-Saturated vapor pressure: 4.245 kPa
・ Sample tube exhaust speed: Normal ・ Introduction pressure Initial introduction amount: 0.20 cm ³ (STP) ・ g ^-1
-Measurement relative pressure range P / P0 (measurement of adsorption process): 0.05, 0.15, 0.25, 0.
35, 0.45, 0.55, 0.65, 0.75, 0.85, 0.90, 0.95
The measurement was performed under the above conditions, and a temperature line for moisture absorption / desorption at a temperature of 30 ° C. was drawn, and the moisture adsorption amount (mg / g) per 1 g of the sample at a humidity of 80% RH in the adsorption process was calculated.

<Measurement of toner weight average particle size (D4)>
As the measuring device, a precision particle size distribution measuring device “Coulter Counter Multisizer 3” (registered trademark, manufactured by Beckman Coulter) equipped with a 100 μm aperture tube by the pore electric resistance method is used. For the setting of measurement conditions and the analysis of measurement data, the attached dedicated software "Beckman Coulter Multisizer 3 Version 3.51" (manufactured by Beckman Coulter) is used. The measurement is performed with 25,000 effective measurement channels.
As the electrolytic aqueous solution used for the measurement, one in which special grade sodium chloride is dissolved in ion-exchanged water so that the concentration becomes about 1% by mass, for example, "ISOTON II" (manufactured by Beckman Coulter) can be used.
Before performing the measurement and analysis, the dedicated software was set as follows.
On the "Change standard measurement method (SOM)" screen of the dedicated software, set the total count number in the control mode to 50,000 particles, measure once, and set the Kd value to "standard particles 10.0 μm" (Beckman Coulter). Set the value obtained using (manufactured by the company). By pressing the "threshold / noise level measurement button", the threshold and noise level are automatically set. Also, set the current to 1600 μA, the gain to 2, and the electrolyte to ISOTON II, and check "Flash of aperture tube after measurement".
On the "Pulse to particle size conversion setting" screen of the dedicated software, the bin spacing is set to logarithmic particle size, the particle size bin is set to 256 particle size bins, and the particle size range is set from 2 μm to 60 μm.

The specific measurement method is as follows.
(1) About 200 ml of the electrolytic aqueous solution is placed in a 250 ml round bottom beaker made of glass dedicated to Multisizer 3, set on a sample stand, and the stirrer rod is stirred counterclockwise at 24 rpm. Then, the dirt and air bubbles in the aperture tube are removed by the "aperture flash" function of the dedicated software.
(2) Put about 30 ml of the electrolytic aqueous solution in a 100 ml flat bottom beaker made of glass. Among them, as a dispersant, "Contaminone N" (a 10% by mass aqueous solution of a neutral detergent for cleaning a pH 7 precision measuring instrument consisting of a nonionic surfactant, an anionic surfactant, and an organic builder, manufactured by Wako Pure Chemical Industries, Ltd. ) Is diluted about 3 times by mass with ion-exchanged water, and about 0.3 ml of the diluted solution is added.
(3) Two oscillators with an oscillation frequency of 50 kHz are built in with their phases shifted by 180 degrees, and an ultrasonic disperser "Ultrasonic Dispersion System Tetora 150" (manufactured by Nikkaki Bios) with an electrical output of 120 W is prepared. About 3.3 L of ion-exchanged water is put into the water tank of the ultrasonic disperser, and about 2 ml of contaminone N is added to this water tank.
(4) The beaker of (2) is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. Then, the height position of the beaker is adjusted so that the resonance state of the liquid level of the electrolytic solution in the beaker is maximized.
(5) With the electrolytic aqueous solution in the beaker of (4) being irradiated with ultrasonic waves, about 10 mg of toner is added little by little to the electrolytic aqueous solution and dispersed. Then, the ultrasonic dispersion processing is continued for another 60 seconds. For ultrasonic dispersion, the water temperature in the water tank is appropriately adjusted to be 10 ° C. or higher and 40 ° C. or lower.
(6) Using a pipette, the electrolytic aqueous solution of (5) in which toner is dispersed is dropped onto the round bottom beaker of (1) installed in the sample stand, and the measured concentration is adjusted to about 5%. .. Then, the measurement is performed until the number of measured particles reaches 50,000.
(7) The measurement data is analyzed by the dedicated software attached to the device, and the weight average particle size (D4) and the number average particle size (D1) are calculated. The "average diameter" on the "analysis / volume statistic (arithmetic mean)" screen when graph / volume% is set with the dedicated software is the weight average particle size (D4), and the graph / volume is set with the dedicated software. The "average diameter" on the "analysis / number statistical value (arithmetic mean)" screen when the number% is set is the number average particle size (D1).

<Measurement method of glass transition temperature (Tg) of toner particles or binder resin>
The glass transition temperature (Tg) of the toner particles or the binder resin is measured at room temperature and humidity according to ASTM D3418-82 using a differential scanning calorimeter (DSC) and MDSC-2920 (manufactured by TA Instruments). Measure. A precisely weighed measurement sample of about 3 mg is used. Put this in an aluminum pan and use an empty aluminum pan as a reference. The measurement temperature range is set to 30 ° C. or higher and 200 ° C. or lower. The temperature is raised to 200 ° C. at a heating rate of 10 ° C./min.
In the DSC curve obtained in the second temperature rise process, the intersection of the line between the midpoint of the baseline before and after the specific heat change and the differential thermal curve is defined as the glass transition temperature Tg.

<Measurement method of Et>
For the measurement of Et, a powder fluidity analyzer equipped with a rotary blade (powder rheometer FT-4, manufactured by Freeman Technology) (hereinafter, also referred to as "FT-4").
Was used.
The principle of the above device is to move the rotary blade in the powder sample to cause a constant pattern of flow. The particles in the powder sample flow when the blades are in close proximity and rest again when they pass. The energy required for the blade to move through the powder is measured and from this value various fluidity indices are calculated. The blade is a propeller type and moves upward or downward at the same time as it rotates, so the tip draws a spiral. The angle and speed of the spiral path of the blade can be adjusted by changing the rotation speed and vertical movement. When the blade moves along a clockwise spiral path with respect to the surface of the powder layer, it has the effect of uniformly mixing the powder. Conversely, when the blade moves along a counterclockwise spiral path with respect to the surface of the powder layer, the blade receives resistance from the powder.
Specifically, the measurement was performed by the following operation. In all operations, the propeller type blade has a 48 mm diameter blade dedicated to FT-4 measurement (a rotation axis exists in the center of the blade plate of 48 mm × 10 mm in the normal direction, and the blade plate has both outermost edges (rotation shaft). It is twisted smoothly counterclockwise, such as 70 ° for the part (24 mm from the part) and 35 ° for the part 12 mm from the axis of rotation. The material is made of SUS. Model number: C210. Hereinafter abbreviated as "blade" In some cases) is used.
First, a 50 mm x 160 ml split container (model number: C203. Height 82 mm from the bottom of the container to the split part. The material is glass. Hereinafter, it may be abbreviated as a container) for FT-4 measurement at 23 ° C., 60% environment. A toner powder layer was formed by adding 100 g of toner left in the container for 3 days or more.
(1) Conditioning operation (a) The rotation speed of the blade (peripheral speed of the outermost edge of the blade) was set to 60 (mm / sec). The vertical approach speed to the powder layer is defined as the angle formed by the outermost edge of the moving blade and the surface of the powder layer (hereinafter, may be abbreviated as "deducted angle") of 5 (deg). ). The blade was inserted from the surface of the powder layer to a position 10 mm from the bottom surface of the toner powder layer in the clockwise rotation direction (the direction in which the powder layer is loosened by the rotation of the blade) with respect to the surface of the powder layer. After that, the rotation speed of the blade is 60 (mm / sec), the vertical approach speed to the powder layer is 2 (deg), and the rotation speed is clockwise with respect to the surface of the powder layer. , The operation of advancing the blade to a position 1 mm from the bottom surface of the toner powder layer was performed. After that, the rotation speed of the blade is 60 (mm / sec), the angle forming the extraction speed from the powder layer is 5 (deg), and the toner powder is rotated clockwise with respect to the surface of the powder layer. The blade was moved to a position 100 mm from the bottom surface of the layer and extracted. When the extraction was completed, the toner adhering to the blade was removed by rotating the blade clockwise and counterclockwise alternately.
(B) By performing the series of operations (1)-(a) five times, the air entrained in the toner powder layer was removed, and a stable toner powder layer was formed.
(2) Split operation The toner powder layer was scraped off at the split portion of the above-mentioned FT-4 measurement dedicated cell, and the toner on the upper part of the powder layer was removed to form a toner powder layer having the same volume.
(3) Measurement operation (a) The same operation as in (1)-(a) above was performed once.
(B) Next, the rotation speed of the blade was set to 100 (mm / sec), and the vertical approach speed to the powder layer was set to a speed with an angle of 5 (deg). The blade was inserted to a position 10 mm from the bottom surface of the toner powder layer in the counterclockwise rotation direction (the direction in which the powder layer is pushed by the rotation of the blade) with respect to the surface of the powder layer. After that, the rotation speed of the blade is 60 (mm / sec), the vertical approach speed to the powder layer is 2 (deg), and the rotation speed is clockwise with respect to the surface of the powder layer. , The operation of advancing the blade to a position 1 mm from the bottom surface of the powder layer was performed. After that, the rotation speed of the blade is 60 (mm / sec), the angle forming the vertical extraction speed from the powder layer is 5 (deg), and the rotation speed is clockwise with respect to the surface of the powder layer. The blade was withdrawn from the bottom surface of the powder layer to a position 100 mm. When the extraction was completed, the toner adhering to the blade was removed by rotating the blade clockwise and counterclockwise alternately.
(C) The series of operations of (b) above was repeated 7 times.
In the operation (c) above, it is obtained when the blade is inserted from the bottom surface of the toner powder layer to a position of 100 mm to 10 mm when the rotation speed of the blade at the seventh time is 100 (mm / sec). Let Et (mJ) be the sum total Et of the rotational torque and the vertical load.

Hereinafter, the present invention will be specifically described based on Examples. However, the invention of the present application is not limited thereto. In the following examples, parts and% are based on mass unless otherwise specified.

The first aspect of the present invention will be described with reference to examples.
<Production example of strontium titanate A-1>
The hydroxide-containing titanium slurry obtained by hydrolyzing an aqueous solution of titanyl sulfate was washed with an aqueous alkaline solution until the electrical conductivity of the supernatant was 50 μS / cm to reduce impurities and purify. Next, hydrochloric acid was added to the hydroxide-containing titanium slurry to adjust the pH to 0.7 to obtain a titania sol dispersion.
A 1.3-fold molar amount of a strontium chloride aqueous solution was added to 2.2 mol (titanium oxide equivalent) of the titania sol dispersion, and the mixture was placed in a reaction vessel and replaced with nitrogen gas. Further, pure water was added so as to be 1.1 mol / L in terms of titanium oxide.
Next, the mixture was stirred and mixed, heated to 90 ° C., and then 440 mL of a 10N sodium hydroxide aqueous solution was added over 15 minutes while applying ultrasonic vibration, and then the reaction was carried out for 20 minutes. Pure water at 5 ° C. was added to the slurry after the reaction and the slurry was rapidly cooled to 30 ° C. or lower, and then the supernatant was removed. Further, an aqueous solution of hydrochloric acid having a pH of 5.0 was added to the slurry and stirred for 1 hour to dissolve and remove strontium carbonate, followed by repeated washing with pure water, and a part of the obtained cake was sampled and dried. X-ray diffraction and fluorescent X-ray measurements were performed. The results are shown in Table 1.
Next, after adding an aqueous hydrochloric acid solution having a pH of 3.0 to the slurry, 7.0% by mass of isobutyltrimethoxysilane was added to the solid content of the slurry, and the mixture was stirred for 10 hours. Then, it was neutralized with an aqueous sodium hydroxide solution, filtered through Nutche, and washed with pure water. The obtained cake was dried to obtain strontium titanate A-1. The physical characteristics are shown in Table 1.

<Production example of strontium titanate A-2>
The hydroxide-containing titanium slurry obtained by hydrolyzing an aqueous solution of titanyl sulfate was washed with an aqueous alkaline solution until the electrical conductivity of the supernatant was 50 μS / cm to reduce impurities and purify. Next, hydrochloric acid was added to the hydroxide-containing titanium slurry to adjust the pH to 0.7 to obtain a titania sol dispersion.
A 1.2-fold molar amount of a strontium chloride aqueous solution was added to 2.6 mol (titanium oxide equivalent) of the titania sol dispersion, and the mixture was placed in a reaction vessel and replaced with nitrogen gas. Further, pure water was added so that the titanium oxide concentration became 1.3 mol / L.
Next, the mixture was stirred and mixed, heated to 95 ° C., and then 312 mL of a 15N sodium hydroxide aqueous solution was added over 5 minutes while applying ultrasonic vibration, and then the reaction was carried out for 20 minutes. Pure water at 5 ° C. was added to the slurry after the reaction and the slurry was rapidly cooled to 30 ° C. or lower, and then the supernatant was removed. Further, an aqueous solution of hydrochloric acid having a pH of 5.0 was added to the slurry and stirred for 1 hour to dissolve and remove strontium carbonate, followed by repeated washing with pure water, and a part of the obtained cake was sampled and dried. X-ray diffraction and fluorescent X-ray measurements were performed. The results are shown in Table 1.
Next, after adding an aqueous hydrochloric acid solution having a pH of 3.0 to the slurry, 5.0% by mass of isobutyltrimethoxysilane was added to the solid content of the slurry, and the mixture was stirred for 10 hours. Then, it was neutralized with an aqueous sodium hydroxide solution, filtered through Nutche, and washed with pure water. The obtained cake was dried to obtain strontium titanate A-2. The physical characteristics are shown in Table 1.

<Production example of strontium titanate A-3>
The hydroxide-containing titanium slurry obtained by hydrolyzing an aqueous solution of titanyl sulfate was washed with an aqueous alkaline solution until the electrical conductivity of the supernatant was 50 μS / cm to reduce impurities and purify. Next, hydrochloric acid was added to the hydroxide-containing titanium slurry to adjust the pH to 0.7 to obtain a titania sol dispersion.
A 1.2-fold molar amount of a strontium chloride aqueous solution was added to 2.0 mol (in terms of titanium oxide) of the titania sol dispersion, and the mixture was placed in a reaction vessel and replaced with nitrogen gas. Further, pure water was added so that the titanium oxide concentration became 1.0 mol / L.
Next, the mixture was stirred and mixed, heated to 85 ° C., and then 800 mL of a 5N sodium hydroxide aqueous solution was added over 20 minutes while applying ultrasonic vibration, and then the reaction was carried out for 20 minutes. Pure water at 5 ° C. was added to the slurry after the reaction and the slurry was rapidly cooled to 30 ° C. or lower, and then the supernatant was removed. Further, an aqueous solution of hydrochloric acid having a pH of 5.0 was added to the slurry and stirred for 1 hour to dissolve and remove strontium carbonate, followed by repeated washing with pure water, and a part of the obtained cake was sampled and dried. X-ray diffraction and fluorescent X-ray measurements were performed. The results are shown in Table 1.
Next, after adding an aqueous hydrochloric acid solution having a pH of 3.0 to the slurry, 30.0% by mass of isobutyltrimethoxysilane was added to the solid content of the slurry, and the mixture was stirred for 10 hours. Then, it was neutralized with an aqueous sodium hydroxide solution, filtered through Nutche, and washed with pure water. The obtained cake was dried to obtain strontium titanate A-3. The physical characteristics are shown in Table 1.

<Production example of strontium titanate A-4>
Strontium titanate A-4 was obtained in the same manner as strontium titanate A-3 except that 4.0% by mass of n-octyltriethoxysilane was used instead of isobutyltrimethoxysilane. The physical characteristics are shown in Table 1.

<Production example of strontium titanate A-5>
Strontium titanate A-5 was obtained in the same manner as strontium titanate A-4 except that the amount of n-octyltriethoxysilane added was changed to 2.0% by mass. The physical characteristics are shown in Table 1.

<Production example of strontium titanate A-6>
The hydroxide-containing titanium slurry obtained by hydrolyzing an aqueous solution of titanyl sulfate was washed with an aqueous alkaline solution until the electrical conductivity of the supernatant was 70 μS / cm to reduce impurities and purify. Next, hydrochloric acid was added to the hydroxide-containing titanium slurry to adjust the pH to 0.7 to obtain a titania sol dispersion.
A 1.1-fold molar amount of a strontium chloride aqueous solution was added to 1.8 mol (titanium oxide equivalent) of the titania sol dispersion, and the mixture was placed in a reaction vessel and replaced with nitrogen gas. Further, pure water was added so that the titanium oxide concentration became 0.9 mol / L.
Next, the mixture was stirred and mixed, heated to 85 ° C., and then 576 mL of a 5N sodium hydroxide aqueous solution was added over 5 minutes while applying ultrasonic vibration, and then the reaction was carried out for 20 minutes. Pure water at 5 ° C. was added to the slurry after the reaction and the slurry was rapidly cooled to 30 ° C. or lower, and then the supernatant was removed. Further, an aqueous solution of hydrochloric acid having a pH of 5.0 was added to the slurry and stirred for 1 hour to dissolve and remove strontium carbonate, followed by repeated washing with pure water, and a part of the obtained cake was sampled and dried. X-ray diffraction and fluorescent X-ray measurements were performed. The results are shown in Table 1.
Next, after adding an aqueous hydrochloric acid solution having a pH of 3.0 to the slurry, 2.0% by mass of n-octyltriethoxysilane with respect to the solid content of the slurry was added, and the mixture was stirred for 10 hours. Then, it was neutralized with an aqueous sodium hydroxide solution, filtered through Nutche, and washed with pure water. The obtained cake was dried to obtain strontium titanate A-6. The physical characteristics are shown in Table 1.

<Production example of strontium titanate A-7>
The hydroxide-containing titanium slurry obtained by hydrolyzing an aqueous solution of titanyl sulfate was washed with an aqueous alkaline solution until the electrical conductivity of the supernatant was 70 μS / cm to reduce impurities and purify. Next, hydrochloric acid was added to the hydroxide-containing titanium slurry to adjust the pH to 0.7 to obtain a titania sol dispersion.
A 1.1-fold molar amount of a strontium chloride aqueous solution was added to 1.8 mol (titanium oxide equivalent) of the titania sol dispersion, and the mixture was placed in a reaction vessel and replaced with nitrogen gas. Further, pure water was added so that the titanium oxide concentration became 0.9 mol / L.
Next, the mixture was stirred and mixed, heated to 80 ° C., and then 792 mL of a 5N sodium hydroxide aqueous solution was added over 40 minutes while applying ultrasonic vibration, and then the reaction was carried out for 20 minutes. The slurry after the reaction was cooled to 30 ° C. or lower over 1 hour, and then the supernatant was removed. Further, an aqueous solution of hydrochloric acid having a pH of 5.0 was added to the slurry and stirred for 1 hour to dissolve and remove strontium carbonate, followed by repeated washing with pure water, and a part of the obtained cake was sampled and dried. X-ray diffraction and fluorescent X-ray measurements were performed. The results are shown in Table 1.
Next, after adding an aqueous hydrochloric acid solution having a pH of 3.0 to the slurry, 2.0% by mass of n-octyltriethoxysilane with respect to the solid content of the slurry was added, and the mixture was stirred for 10 hours. Then, it was neutralized with an aqueous sodium hydroxide solution, filtered through Nutche, and washed with pure water. The obtained cake was dried to obtain strontium titanate A-7. The physical characteristics are shown in Table 1.

<Production example of strontium titanate A-8>
The hydroxide-containing titanium slurry obtained by hydrolyzing an aqueous solution of titanyl sulfate was washed with an aqueous alkaline solution until the electrical conductivity of the supernatant became 100 μS / cm to reduce impurities and purify. Next, hydrochloric acid was added to the hydroxide-containing titanium slurry to adjust the pH to 0.7 to obtain a titania sol dispersion.
A 1.1-fold molar amount of a strontium chloride aqueous solution was added to 1.4 mol (titanium oxide equivalent) of the titania sol dispersion, and the mixture was placed in a reaction vessel and replaced with nitrogen gas. Further, pure water was added so that the titanium oxide concentration became 0.7 mol / L.
Next, the mixture was stirred and mixed, heated to 80 ° C., and then 1000 mL of a 3N sodium hydroxide aqueous solution was added over 40 minutes while applying ultrasonic vibration, and then the reaction was carried out for 20 minutes. The slurry after the reaction was cooled to 30 ° C. or lower over 1 hour, and then the supernatant was removed. Further, an aqueous solution of hydrochloric acid having a pH of 5.0 was added to the slurry and stirred for 1 hour to dissolve and remove strontium carbonate, followed by repeated washing with pure water, and a part of the obtained cake was sampled and dried. X-ray diffraction and fluorescent X-ray measurements were performed. The results are shown in Table 1.
Next, after adding an aqueous hydrochloric acid solution having a pH of 3.0 to the slurry, 2.0% by mass of n-octyltriethoxysilane with respect to the solid content of the slurry was added, and the mixture was stirred for 10 hours. Then, it was neutralized with an aqueous sodium hydroxide solution, filtered through Nutche, and washed with pure water. The obtained cake was dried to obtain strontium titanate A-8. The physical characteristics are shown in Table 1.

<Production example of strontium titanate A-9>
The hydroxide-containing titanium slurry obtained by hydrolyzing an aqueous solution of titanyl sulfate was washed with an aqueous alkaline solution until the electrical conductivity of the supernatant became 100 μS / cm to reduce impurities and purify. Next, hydrochloric acid was added to the hydroxide-containing titanium slurry to adjust the pH to 0.7 to obtain a titania sol dispersion.
A 1.1-fold molar amount of a strontium chloride aqueous solution was added to 1.0 mol (titanium oxide equivalent) of the titania sol dispersion, and the mixture was placed in a reaction vessel and replaced with nitrogen gas. Further, pure water was added so that the titanium oxide concentration became 0.5 mol / L.
Next, the mixture was stirred and mixed, heated to 70 ° C., and then 1100 mL of a 2N sodium hydroxide aqueous solution was added over 40 minutes while applying ultrasonic vibration, and then the reaction was carried out for 20 minutes. The slurry after the reaction was cooled to 30 ° C. or lower over 1 hour, and then the supernatant was removed. Further, an aqueous solution of hydrochloric acid having a pH of 5.0 was added to the slurry and stirred for 1 hour to dissolve and remove strontium carbonate, followed by repeated washing with pure water, and a part of the obtained cake was sampled and dried. X-ray diffraction and fluorescent X-ray measurements were performed. The results are shown in Table 1.
Next, after adding an aqueous hydrochloric acid solution having a pH of 3.0 to the slurry, 2.0% by mass of n-octyltriethoxysilane with respect to the solid content of the slurry was added, and the mixture was stirred for 10 hours. Then, it was neutralized with an aqueous sodium hydroxide solution, filtered through Nutche, and washed with pure water. The obtained cake was dried to obtain strontium titanate A-9. The physical characteristics are shown in Table 1.

<Production example of strontium titanate A-10>
The hydroxide-containing titanium slurry obtained by hydrolyzing an aqueous solution of titanyl sulfate was washed with an aqueous alkaline solution until the electrical conductivity of the supernatant became 100 μS / cm to reduce impurities and purify. Next, hydrochloric acid was added to the hydroxide-containing titanium slurry to adjust the pH to 0.7 to obtain a titania sol dispersion.
A 1.1-fold molar amount of a strontium chloride aqueous solution was added to 1.0 mol (titanium oxide equivalent) of the titania sol dispersion, and the mixture was placed in a reaction vessel and replaced with nitrogen gas. Further, pure water was added so that the titanium oxide concentration became 0.5 mol / L.
Next, the mixture was stirred and mixed, heated to 70 ° C., 1200 mL of a 2N sodium hydroxide aqueous solution was added over 240 minutes, and then the reaction was carried out for 20 minutes. The slurry after the reaction was cooled to 30 ° C. or lower over 1 hour, and then the supernatant was removed. Further, an aqueous hydrochloric acid solution having a pH of 5.0 was added to the slurry and stirred for 1 hour to dissolve and remove strontium carbonate, then washed with pure water and dried to obtain inorganic fine particles a. The half width of the inorganic fine particles a was 0.15. Further, the inorganic fine particles a were placed in an automatic discharge ball mill (manufactured by Eisin Co., Ltd.) together with 4 mm alumina balls and stirred for 200 hours. Then, the alumina balls were removed and washed, and after drying, X-ray diffraction and fluorescent X-ray measurement of the obtained inorganic fine particles were performed. The physical characteristics are shown in Table 1.
Next, the inorganic fine particles were placed in a closed high-speed stirrer and stirred while replacing with nitrogen. A treatment agent obtained by diluting 4% by mass of dimethyl silicone oil with hexane 6.5 times with respect to the solid content of the slurry was sprayed into the stirrer. After spraying the entire amount of the treatment agent, the temperature inside the stirrer was raised to 350 ° C. while stirring, and the mixture was stirred for 3 hours. The temperature inside the stirrer was returned to room temperature while stirring, and the mixture was taken out and then crushed with a pin mill to obtain strontium titanate A-10. The physical characteristics are shown in Table 1.

<Production example of strontium titanate A-11>
The hydroxide-containing titanium slurry obtained by hydrolyzing an aqueous solution of titanyl sulfate was washed with an aqueous alkaline solution until the electrical conductivity of the supernatant was 100 μS / cm to reduce impurities and purify. Next, hydrochloric acid was added to the hydroxide-containing titanium slurry to adjust the pH to 0.7 to obtain a titania sol dispersion.
A 1.0-fold molar amount of a strontium chloride aqueous solution was added to 1.0 mol (in terms of titanium oxide) of the titania sol dispersion, and the mixture was placed in a reaction vessel and replaced with nitrogen gas. Further, pure water was added so that the titanium oxide concentration became 0.5 mol / L.
Next, the mixture was stirred and mixed, heated to 70 ° C., and then 1100 mL of a 2N sodium hydroxide aqueous solution was added over 40 minutes while applying ultrasonic vibration, and then the reaction was carried out for 20 minutes. The slurry after the reaction was cooled to 30 ° C. or lower over 1 hour, and then the supernatant was removed. Further, the slurry was repeatedly washed with pure water, a part of the obtained cake was sampled, dried, and then X-ray diffraction and fluorescent X-ray measurement were performed. The results are shown in Table 1.
Next, after adding an aqueous hydrochloric acid solution having a pH of 3.0 to the slurry, 1.0% by mass of n-octyltriethoxysilane with respect to the solid content of the slurry was added, and the mixture was stirred for 10 hours. Then, it was neutralized with an aqueous sodium hydroxide solution, filtered through Nutche, and washed with pure water. The obtained cake was dried to obtain strontium titanate A-11. The physical characteristics are shown in Table 1.

<Production example of strontium titanate A-12>
The hydroxide-containing titanium slurry obtained by hydrolyzing an aqueous solution of titanyl sulfate was washed with an aqueous alkaline solution until the electrical conductivity of the supernatant became 100 μS / cm to reduce impurities and purify. Next, hydrochloric acid was added to the hydroxide-containing titanium slurry to adjust the pH to 0.7 to obtain a titania sol dispersion.
A 1.0-fold molar amount of a strontium chloride aqueous solution was added to 0.6 mol (in terms of titanium oxide) of the titania sol dispersion, and the mixture was placed in a reaction vessel and replaced with nitrogen gas. Further, pure water was added so that the titanium oxide concentration became 0.3 mol / L.
Next, the mixture was stirred and mixed, heated to 70 ° C., 750 mL of a 2N sodium hydroxide aqueous solution was added over 120 minutes, and then the reaction was carried out for 20 minutes. The slurry after the reaction was cooled to 30 ° C. or lower over 1 hour, and then the supernatant was removed. Further, the slurry was washed with pure water, dried, and then X-ray diffraction and fluorescent X-ray measurement of the obtained inorganic fine particles were performed. The physical characteristics are shown in Table 1.
Next, the inorganic fine particles were placed in a closed high-speed stirrer and stirred while replacing with nitrogen. A treatment agent obtained by diluting 2% by mass of dimethyl silicone oil with hexane 6.5 times with respect to the solid content of the slurry was sprayed into the stirrer. After spraying the entire amount of the treatment agent, the temperature inside the stirrer was raised to 350 ° C. while stirring, and the mixture was stirred for 3 hours. The temperature inside the stirrer was returned to room temperature while stirring, and the mixture was taken out and then crushed with a pin mill to obtain strontium titanate A-12. The physical characteristics are shown in Table 1.

<Production example of strontium titanate A-13>
The hydroxide-containing titanium slurry obtained by hydrolyzing an aqueous solution of titanyl sulfate was washed with an aqueous alkaline solution until the electrical conductivity of the supernatant was 200 μS / cm to reduce impurities and purify. Next, hydrochloric acid was added to the hydroxide-containing titanium slurry to adjust the pH to 0.7 to obtain a titania sol dispersion.
A 1.0-fold molar amount of a strontium chloride aqueous solution was added to 0.6 mol (in terms of titanium oxide) of the titania sol dispersion, and the mixture was placed in a reaction vessel and replaced with nitrogen gas. Further, after adding 0.05 mol of aluminum sulfate, pure water was added so that the titanium oxide concentration became 0.3 mol / L.
Next, the mixture was stirred and mixed, heated to 70 ° C., and then 450 mL of a 2N sodium hydroxide aqueous solution was added over 5 minutes while applying ultrasonic vibration, and then the reaction was carried out for 20 minutes. Pure water at 5 ° C. was added to the slurry after the reaction and the slurry was rapidly cooled to 30 ° C. or lower, and then the supernatant was removed. Further, the slurry was washed with pure water, dried, and then X-ray diffraction and fluorescent X-ray measurement of the obtained inorganic fine particles were performed. The physical characteristics are shown in Table 1.
Next, the inorganic fine particles were placed in a closed high-speed stirrer and stirred while replacing with nitrogen. A treatment agent obtained by diluting 2% by mass of dimethyl silicone oil with hexane 6.5 times with respect to the solid content of the slurry was sprayed into the stirrer. After spraying the entire amount of the treatment agent, the temperature inside the stirrer was raised to 350 ° C. while stirring, and the mixture was stirred for 3 hours. The temperature inside the stirrer was returned to room temperature while stirring, and the mixture was taken out and then crushed with a pin mill to obtain strontium titanate A-13. The physical characteristics are shown in Table 1.
Strontium titanate A-1 to A-13 had a maximum peak (a) at a diffraction angle (2θ) of 32.00 deg or more and 32.40 deg or less in CuKα characteristic X-ray diffraction.

<Manufacturing example of binder resin A-1>
-Bisphenol A ethylene oxide (2.2 mol adduct): 60.0 mol parts-Bisphenol A propylene oxide (2.2 mol adduct): 40.0 mol parts-Terephthalic acid: 100.0 mol parts Consists of the above polyester unit 100 parts of the monomer to be added was charged into a 5 liter autoclave. A reflux condenser, a moisture separator, an _N2 gas introduction tube, a thermometer and a stirrer were attached thereto, and a polycondensation reaction was carried out at 230 ° C. while introducing _N2 gas into the autoclave. After completion of the reaction, the mixture was taken out from the container, cooled and pulverized to obtain a binder resin A-1.

<Example A-1>
(Manufacturing example of toner A-1)
-Bound resin A-1 100 parts-Fishertro push wax: 5 parts (melting point 105 ° C)
-Magnetic iron oxide particles: 90 parts (number average particle size 0.20 μm, Hc (countermagnetic force) = 10 kA / m, σs (saturation magnetization) = 83
Am ² / kg, σr (residual magnetization) = 13 Am ² / kg)
-Aluminum compound of 3,5-di-tert-butylsalicylic acid: Part 1 The above materials were premixed with a Henschel mixer and then melt-kneaded by a twin-screw kneading extruder.
The obtained kneaded product is cooled, roughly pulverized with a hammer mill, then pulverized with a jet mill, and the obtained finely pulverized powder is classified using a multi-division classifier utilizing the coranda effect to obtain a weight average particle size (weight average particle size (). D4) Negative friction chargeable toner particles of 6.8 μm were obtained. The Tg of the toner particles was 60 ° C. For 100 parts of the toner particles, 1 part of strontium titanate A-1 and 1.0 part of hydrophobic silica fine powder (specific surface area by nitrogen adsorption measured by BET method is 140 m ² / g) are externally added by a Henshell mixer. Mixed.
Regarding external mixing, in order to control the fluidity of the toner, while monitoring the temperature inside the tank of the mixer, the chilled water temperature and chilled water flow rate of the chilled water jacket attached to the processing device are adjusted, and the inside of the tank of the mixer is adjusted. The temperature was adjusted to 45 ° C. to control the adhesion state of the external additive. Then, the toner A-1 was obtained by sieving with a mesh having an opening of 150 μm. Table 2 shows the physical characteristics of the toner A-1.

The evaluation was carried out by modifying the process speed of a commercially available digital copying machine (imageRUNNER 4051, manufactured by Canon Inc.) to 252 mm / s. As the evaluation paper, CS-680 (68.0 g / m ² paper, A4) (sold by Canon Marketing Japan Co., Ltd.) was used. Further, as the output image in the durability test, an image having a printing rate of 5% was used.

<Evaluation of sleeve ghost in low temperature and low humidity environment>
The sleeve ghost was evaluated as follows under a low temperature and low humidity (15 ° C., 10% RH) environment.
After passing 999 sheets of a solid black vertical band as shown in FIG. 1 and a test chart which is solid white except for the vertical band in succession, the 1000th sheet was subjected to a full halftone image in the same job.
On the halftone image, the image densities of the region (a) through which the solid black vertical band in FIG. 2 was passed and the region (b) through which the solid white was passed were measured, and the sleeve ghost was measured by the difference in shade. Was evaluated. The area (a) and the area (b) are the range of the first lap of the sleeve.
The image density is X-Rite color reflection densitometer (X-Rite 50, manufactured by X-Rite).
It was measured using 0Series).
A: Concentration difference between region (a) and region (b) is less than 0.02 B: Concentration difference between region (a) and region (b) is 0.02 or more and less than 0.04 C: Region (a) and region The concentration difference in (b) is 0.04 or more and less than 0.06 D: The concentration difference between the region (a) and the region (b) is 0.06 or more and less than 0.10.

<Evaluation of sleeve ghost in high temperature and high humidity environment>
The evaluation was performed as follows under a high temperature and high humidity (32.5 ° C., 80% RH) environment. After performing a continuous paper passing test for up to 100,000 images with a print ratio of 5%, a solid black vertical band as shown in Fig. 1 and a test chart that is solid white except for the vertical band are passed continuously for 999 sheets. After printing, the 1000th sheet was printed in the same job, and a full halftone image was played.
On the halftone image, the image densities of the region (a) through which the solid black vertical band in FIG. 2 was passed and the region (b) through which the solid white was passed were measured, and the sleeve ghost was measured by the difference in shade. Was evaluated. The area (a) and the area (b) are the range of the first lap of the sleeve.
The image density is X-Rite color reflection densitometer (X-Rite 50, manufactured by X-Rite).
It was measured using 0Series).
A: Concentration difference between region (a) and region (b) is less than 0.02 B: Concentration difference between region (a) and region (b) is 0.02 or more and less than 0.04 C: Region (a) and region The concentration difference in (b) is 0.04 or more and less than 0.06 D: The concentration difference between the region (a) and the region (b) is 0.06 or more and less than 0.10.

<Evaluation of dot reproducibility>
In the evaluation of dot reproducibility, after 100,000 images were output in a high temperature and high humidity (32.5 ° C., 80% RH) environment, one isolated 1-dot halftone image was printed on A4 sheet. The image was measured with an area of 1000 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.
Dot reproducibility index (I) = σ / S × 100
The smaller the dot reproducibility index (I), the better the dot reproducibility.
A: I is less than 2.0.
B: I is 2.0 or more and less than 3.0.
C: I is 3.0 or more and less than 5.0.
D: I is 5.0 or more and less than 7.0.

<Thin line reproducibility>
The evaluation of fine line reproducibility is an image (printing area) in which a grid pattern with a line width of 3 pixels is printed on the entire surface of A4 paper after 100,000 images are output in a high temperature and high humidity (32.5 ° C, 80% RH) environment. (Ratio 4%) was printed, and the fine line reproducibility was evaluated according to the following evaluation criteria. The line width of 3 pixels is theoretically 127 μm. The line width of the image was measured with a microscope VK-8500 (manufactured by KEYENCE). When 5 points were randomly selected and the line width was measured and the average value of 3 points excluding the minimum value and the maximum value was d (μm), the following L was defined as the fine line reproducibility index.
L (μm) = | 127-d |
L defines the difference between the theoretical line width of 127 μm and the line width d on the output image. Since d may be larger than 127 or smaller than 127, it is defined as the absolute value of the difference. The smaller L is, the better the fine line reproducibility is shown.
(Evaluation criteria)
A: L is 0 μm or more and less than 5 μm.
B: L is 5 μm or more and less than 10 μm.
C: L is 10 μm or more and less than 15 μm.
D: L is 15 μm or more and less than 20 μm.

<Image density>
As the image to be evaluated, an original image in which 5 solid black patches of 20 mm square were arranged in the development area was used. In a normal temperature and humidity (23 ° C., 55% RH) environment, a continuous paper passing test was performed on up to 100,000 images having a printing ratio of 5%. After outputting 100,000 sheets, an original image in which 20 mm square solid black patches were arranged at five locations in the development area was output, and the average of the five points was taken as the image density.
The image density is an X-Rite color reflection densitometer (manufactured by X-rite, X-rite).
It was measured using 500 Series).
A: Image density 1.45 or more B: Image density 1.40 or more and less than 1.45

<Fog>
For fog, a continuous paper passing test was performed on up to 100,000 images having a printing ratio of 5% under a normal temperature and humidity (23 ° C., 55% RH) environment, and then a solid white image was evaluated according to the following criteria. The measurement was performed using a reflectance meter (reflect meter model TC-6DS manufactured by Tokyo Denshoku Co., Ltd.), and the worst value of the white background reflection density after image formation was Ds, and the reflection average density of the transfer material before image formation was determined. The fog was evaluated by using Dr as Dr and Dr-Ds as the amount of fog. Therefore, the smaller the value, the less fog.
(Evaluation criteria)
A: Fog is less than 1.0 B: In each evaluation item of fog of 1.0 or more and less than 2.0, all the toners A-1 of Example A-1 were judged as A.

(Manufacturing example of toners A-2 to A-11)
Weight average particle size of toner, type and amount of strontium titanate added and amount of hydrophobic silica fine powder added, temperature in the tank of the mixer when toner particles and strontium titanate and hydrophobic silica fine powder are externally mixed. Toners A-2 to A-11 were obtained in the same manner as in the production example of toner A-1 except that the above was changed as shown in Table 2.

<Examples A-2 to A-11>
Toners A-2 to A-11 were evaluated in the same manner as in Example A-1. The evaluation results are shown in Table 3.

<Comparative Examples A-1 to A-3>
(Manufacturing example of toners A-12 to A-14)
Toner A-12 is the same as the production example of toner A-1, except that the weight average particle size of the toner, the type and amount of strontium titanate added, and the amount of hydrophobic silica fine powder added are changed as shown in Table 4. ~ A-14 was obtained.

Toners A-12 to A-14 were evaluated in the same manner as in Example A-1. The evaluation results are shown in Table 5.

The following second aspect of the present invention will be described with reference to examples. Hereinafter, Examples B-1 to B-16 will be referred to as Reference Examples B-1 to B-16, respectively.

<Production example of inorganic fine particles B-1>
1500 parts of strontium carbonate and 800 parts of titanium oxide were wet-mixed in a ball mill for 8 hours, then filtered and dried, and the mixture was formed at a pressure of 5 kg / cm ² and calcined at 1300 ° C. for 8 hours. This was mechanically pulverized to obtain inorganic fine particles B-1 having an average number of primary particles of 1000 nm.

<Production example of inorganic fine particles B-2 to B-7>
Inorganic fine particles B-2 to B-7 were obtained in the same manner as the inorganic fine particles B-1, except that the pulverization conditions were adjusted so as to have a desired particle size. Table 6 shows the average particle size of each number.

<Manufacturing example of binder resin B-1>
-Propylene oxide adduct of bisphenol A 34.0 mol% (average number of mol added: 2.2 mol)
19.5 mol% of ethylene oxide adduct of bisphenol A (average number of mol added: 2.2 mol)
・ Isophthalic acid 23.5 mol% ・ n-dodecenyl succinic acid 13.5 mol% ・ Trimellitic acid 9.5 mol%
0.03 part of dibutyltin oxide was added to the above monomer with respect to 100 parts of the total acid component and reacted at 220 ° C. for 6 hours under a nitrogen stream to obtain a binder resin B-1. The softening point was 135 ° C. and Tg was 65 ° C.

<Example B-1>
(Manufacturing example of toner B-1)
-Bound resin B-1 100 parts-Fishertro push wax (melting point 105 ° C): 5 parts-Magnetic iron oxide particles: 90 parts (number average particle size 0.20 μm, Hc (coercive force) = 10 kA / m, σs (Saturation magnetization) = 83 Am ² / kg, σr (residual magnetization) = 13 Am ² / kg)
-Aluminum compound of 3,5-di-tert-butylsalicylic acid: Part 1 The above materials were premixed with a Henschel mixer and then melt-kneaded by a twin-screw kneading extruder.
The obtained kneaded product is cooled, roughly pulverized with a hammer mill, then pulverized with a jet mill, and the obtained finely pulverized powder is classified using a multi-division classifier utilizing the coranda effect to obtain a weight average particle size (weight average particle size (). D4) Negative friction chargeable toner particles of 6.8 μm were obtained. 1.0 part of strontium titanate A-1 as inorganic fine particles A, 3.0 parts of inorganic fine particles B-1 and hydrophobic silica fine powder (ratio by nitrogen adsorption measured by BET method) to 100 parts of the toner particles. 1.0 part of the surface area was 140 m ² / g), and the mixture was externally mixed and sieved with a mesh having an opening of 150 μm to obtain toner B-1. Table 7 shows the physical characteristics of the toner B-1.

The evaluation was carried out by modifying the process speed of a commercially available digital copying machine (imageRUNNER 4051, manufactured by Canon Inc.) to 252 mm / s.
<Evaluation of sleeve ghost in low temperature and low humidity environment (LL)>
The evaluation was performed in the same manner as the evaluation of the sleeve ghost in the low temperature and low humidity environment in the first aspect.

<Evaluation of sleeve ghost in high temperature and high humidity environment (HH)>
The evaluation was performed in the same manner as the evaluation of the sleeve ghost in the high temperature and high humidity environment in the first aspect.

<Evaluation of white streaks>
The white streaks were evaluated as follows under a low temperature and low humidity (15 ° C., 10% RH) environment. 100,000 A4 images with a printing rate of 70% were continuously output. The presence or absence of white streaks on the image during paper passing and the presence or absence of streaks due to agglomerates on the sleeve after the completion of durable paper passing were checked and evaluated as follows.
A: No white streaks were found on the image and sleeve during the paper passing durability.
B: No white streaks were seen on the image, but slight streaks were seen on the sleeve.
C: No white streaks were seen on the image, but streaks were seen on the sleeve.
D: White streaks were generated on the image.

<Evaluation of poor cleaning>
The evaluation of poor cleaning was performed as follows. The pressing pressure of the cleaning member against the photoconductor was changed to 0.52N (0.53kgf), and the temperature was low and the humidity was low (15 ° C / 10%).
Under RH), 100,000 A4 character charts with a printing rate of 5% were continuously output. The image during paper passing was checked for vertical streaks due to poor cleaning, and after the durable paper was passed, the state of contamination of the charged member with toner and external additives was checked and evaluated according to the following criteria.
A: No image defects due to poor cleaning are observed through the durability of the paper, and the contaminated state of the charged member after the completion of the durability of the paper is also good.
B: Image defects due to poor cleaning are not seen through the durable paper passing, but light contamination is seen on the charged member after the durable paper passing is completed.
C: Image defects due to poor cleaning are not seen through the durable paper passing, but contamination is seen on the charged member after the durable paper passing is completed.
D: There was an image defect due to poor cleaning in the paper passing durability.

In each of the above evaluation items, all the toners B-1 of Example B-1 were judged as A.
<Examples B-2 to B-16>
(Manufacturing example of toners B-2 to B-16)
Toners B-2 to B-16 were prepared in the same manner as in the production example of toner B-1 except that the weight average particle size of the toner, the types of the inorganic fine particles A and the inorganic fine particles B, and the addition amount were changed as shown in Table 7. Obtained. Moreover, these were evaluated in the same manner as the toner B-1. The evaluation results are shown in Table 8.

<Comparative Examples B-1 to B-4>
(Manufacturing example of toners B-17 to B-20)
Toners B-17 to B-20 were obtained in the same manner as in Example B-1 except that the particle size of the toner particles, the types of the inorganic fine particles A and the inorganic fine particles B, and the addition amount were changed as shown in Table 9. .. Then, the toners B-17 to B-20 were evaluated by the same method as in Example B-1. The evaluation results are shown in Table 10.

Claims (3)

A toner containing toner particles and strontium titanate particles .
The number average particle size of the primary particles of the strontium titanate particles is 10 nm or more and 95 nm or less.
The strontium titanate particles have a maximum peak (a) at a diffraction angle (2θ) of 32.000 deg or more and 32.40 deg or less in CuKα characteristic X-ray diffraction.
The half width of the maximum peak (a) is 0.23 deg or more and 0.50 deg or less.
The intensity (Ia) of the maximum peak (a) and the diffraction angle (2θ) in CuKα characteristic X-ray diffraction.
The maximum peak intensity (Ix) in the range of 24.00 deg or more and 28.00 deg or less satisfies the following formula (1).
(Ix) / (Ia) ≤ 0.010 ... (1)
The strontium titanate particles have the total content of strontium oxide and titanium oxide when the total amount of all oxides is 100% by mass, assuming that all the elements detected by fluorescent X-ray analysis are oxides. , 98.0% by mass or more,
In the powder fluidity analysis of the toner, the peripheral speed of the outermost edge of the propeller type blade is rotated at 100 mm / sec and vertically penetrated into the powder layer of the toner in the measuring container to obtain the powder layer. A toner characterized in that the total Et of the rotational torque and the vertical load obtained when the measurement is started from a position 100 mm from the bottom surface and is advanced to a position 10 mm from the bottom surface is 100 mJ or more and 2000 mJ or less. The toner according to claim 1, wherein the content of the strontium titanate particles is 0.05 parts by mass or more and 2.0 parts by mass or less with respect to 100 parts by mass of the toner particles. The toner according to claim 1 or 2, wherein the strontium titanate particles are surface-treated with a silane coupling agent.

Images