JP5615156B2 - toner - Google Patents

Description

  The present invention relates to a toner used in an electrophotographic system, an electrostatic recording system, an electrostatic printing system, and a toner jet system.

In recent years, as a transfer material for full-color printers, full-color copiers, full-color multifunction peripherals, etc., it supports various materials such as plain paper and OHT, thick paper such as glossy paper, cards, and embossed paper with uneven surfaces. The need for Therefore, a transfer method using an intermediate transfer member has become mainstream.
Usually, in a transfer method using an intermediate transfer member, it is necessary to transfer the visualized toner image from the image carrier to the intermediate transfer member, and then transfer the toner image from the intermediate transfer member to the transfer material again. Since the number of times of transfer increases as compared with the conventional method, there is a concern that the dot reproducibility (ragging), which is a cause of image quality deterioration, and transfer efficiency are deteriorated.

  Also, full-color image forming apparatuses for the POD market are required to have high developability that can stably output high-quality printed matter. Further, in the POD market, bookbinding and package printing are required, and thus the strength (bending resistance) of the printed image is required.

Therefore, the toner has durability and stability that can maintain high transferability and high developability even in a state where high stress is applied to the toner due to stirring in the developing device for a long period of time, and has excellent bending resistance. It is desirable to be able to output an image.
Thus, as one of methods for improving durability and transferability, studies have been recently made to improve durability and transferability by externally adding various fine particles to the toner surface.

  For example, Patent Document 1 proposes a toner having an average primary particle diameter of 80 nm to 150 nm and a dot distribution that is improved by attaching an external additive having a specific distribution to toner particles. However, in the above proposal, no examination has been made regarding the state of adhesion of the external additive to the toner surface. In studies on high-speed printing such as in the POD market, further improvements are required such that the external additive is easily embedded in the toner and stable charging cannot be obtained, resulting in large density fluctuations and reduced transfer efficiency.

  Patent Document 2 proposes a toner externally added with mixed fine particles of small particle size particles having a volume average particle size of 5 nm or more and less than 80 nm and large particle size particles of 80 nm or more and less than 200 nm. In the above proposal, by improving the adhesive force between the toners, an improvement in “hollow-out” in which only a central portion such as a thin line which is one of transfer defects is not transferred. However, in a test in high-speed printing, dot reproducibility is not sufficient at the time of transfer, and further improvement is required.

  For the purpose of improving image strength, for example, Patent Document 3 proposes a toner containing urethane particles. In the above proposal, the strength of the image is obtained by the urethane particles relaxing the strength applied to the image during bending. However, when the particle size of the urethane particles is large, particularly when glossy paper is output, uneven glossiness may be noticeable.

Thus, in high speed printing as the POD market, have durable stability capable of maintaining a high transferability and high development properties over a long period of time, have toner obtained that can output images having excellent bending resistance Absent.

Japanese Patent No. 3987794 JP 2008-262171 A JP 2009-198972 A

  An object of the present invention is to provide a toner that solves the above problems. Specifically, the present invention provides a toner that has durability stability capable of maintaining high transferability and high developability over a long period of time and can output an image having excellent folding resistance.

  As a result of intensive studies, the present inventors have obtained durability images that can maintain high transferability and high developability over a long period of time by using the toner of the present invention, and have excellent folding resistance images. It has been found that a toner that can be output can be obtained.

That is, the present invention is as follows.
In a toner having toner particles containing at least a binder resin, a colorant, and wax and silica particles, the number average particle diameter (D1) of the silica particles is 0.06 μm or more and 0.20 μm or less, and the degree of compression Cs is 15 0.0% or more and 40.0% or less,
The toner is the toner according to satisfy the relationship below following formula (1).
1.05 ≦ P1 / P2 ≦ 2.00 Formula (1)
[In Formula (1),
i) P1 = Pa / Pb
In the FT-IR spectrum of the toner obtained by measurement under the conditions of Ge as an ATR crystal and an infrared light incident angle of 45 ° using the ATR method,
Is a value obtained by subtracting the mean value of the absorption peak intensity of 2843cm ^-1 or 2853cm ^-1 3050cm ^-1 from the maximum value of the absorption peak intensity of the range and 2600 cm ^-1, the maximum endothermic peak intensity "Pa",
Is a value obtained by subtracting the mean value of the absorption peak intensity of 1713 cm ^-1 or 1723cm ^-1 1763cm ^-1 from the maximum value of the absorption peak intensity of the range and 1630 cm ^-1, the maximum endothermic peak intensity "Pb",
ii) P2 = Pc / Pd,
In the FT-IR spectrum of the toner obtained by measurement under the conditions of KRS5 as the ATR crystal and 45 ° as the infrared light incident angle using the ATR method,
Is a value obtained by subtracting the mean value of the absorption peak intensity of 2843cm ^-1 or 2853cm ^-1 3050cm ^-1 from the maximum value of the absorption peak intensity of the range and 2600 cm ^-1, the maximum endothermic peak intensity "Pc",
Is a value obtained by subtracting the mean value of the absorption peak intensity of 1713 cm ^-1 or 1723cm ^-1 1763cm ^-1 from the maximum value of the absorption peak intensity of the range and 1630 cm ^-1, the maximum endothermic peak intensity is "Pd". ]

  By using the toner of the present invention, it is possible to output an image having durability stability capable of maintaining high transferability and high developability over a long period of time and having excellent bending resistance.

1 is a schematic cross-sectional view of a surface treatment apparatus of the present invention. The example of an image which evaluated the bending tolerance of this invention is shown.

  Hereinafter, the best mode for carrying out the present invention will be described in detail.

The present invention relates to a toner having silica particles and toner particles containing at least a binder resin, a colorant and a wax, and the number average particle diameter (D1) of the silica particles is 0.06 μm or more and 0.20 μm or less. Degree Cs is 15.0% or more and 40.0% or less,
The toner has a maximum absorption peak in the range of 2843 cm ⁻¹ or more and 2853 cm ⁻¹ or less in an FT-IR spectrum obtained by measurement using an ATR method under the conditions of Ge as an ATR crystal and an incident angle of infrared light of 45 °. The intensity is Pa, the maximum absorption peak intensity in the range of 1713 cm ⁻¹ or more and 1723 cm ⁻¹ or less is Pb,
In the FT-IR spectrum obtained by measurement using the ATR method under the conditions of KRS5 as the ATR crystal and 45 ° as the infrared light incident angle, the maximum absorption peak intensity in the range of 2843 cm ^{−1 to} 2853 cm ⁻¹ is Pc, When the maximum absorption peak intensity in the range from 1713 cm ^{−1 to} 1723 cm ⁻¹ is defined as Pd, the relationship of the following formula (1) is satisfied.

1.05 ≦ P1 / P2 ≦ 2.00 Formula (1)

In [formula (1), said maximum absorption peak intensity Pa is subtracted the mean value of the absorption peak intensity of 3050 cm ^-1 and 2600 cm ^-1 from the maximum value of the absorption peak intensity of 2843cm ^-1 or 2853cm ^-1 the range and a value, said maximum absorption peak intensity Pb is a value obtained by subtracting the mean value of the absorption peak intensity of 1763cm ^-1 and 1630 cm ^-1 from the maximum value of the absorption peak intensity of 1713 cm ^-1 or 1723 cm ^-1 or less in the range There, said maximum absorption peak intensity Pc is a value obtained by subtracting the mean value of the absorption peak intensity of 3050 cm ^-1 and 2600 cm ^-1 from the maximum value of the absorption peak intensity of 2843cm ^-1 or 2853cm ^-1 the range, the maximum absorption peak intensity Pd is the maximum value of the absorption peak intensity of 1713 cm ^-1 or 1723 cm ^-1 or less in the range 1763cm ^-1 and 1630 is a value obtained by subtracting the mean value of the absorption peak intensity at m ^-1, is P1 = Pa / Pb, P2 = Pc / Pd. ]

  For the following three reasons, it is possible to obtain a durable and stable toner that can maintain high transferability and high developability over a long period of time.

First, it is important that the silica particles used in the present invention have a compression degree Cs obtained from the following formula (2) of 15.0% or more and 40.0% or less.
Compression degree Cs (%) = 100 × (Ps−As) / Ps (2)
(In the formula, As is the loose apparent density (g / cm ³ ) of the silica particles, and Ps is the solid apparent density (g / cm ³ ) of the silica particles)

When the compression degree Cs of the silica particles is within the above range, the silica particles are appropriately dispersed on the surface of the toner particles during the external addition, and are uniformly adhered, and a stable image density can be obtained over a long period of time.
In order to maximize the effect of silica particles as an external additive, it is important that the particles are uniformly attached to the surface of the toner particles. In order to further improve the durability of the toner, it is necessary to attach the silica particles to the convex portions on the surface of the toner particles to which the silica particles are difficult to adhere and to suppress the embedding on the toner surface during the durability.
Here, the degree of compression is an index indicating the ease of loosening of the powder. It indicates that the higher the degree of compression, the more difficult it is for the powder to loosen from the compressed and aggregated state (packed state). On the other hand, the smaller the degree of compression, the easier it is to loosen even in a compressed and agglomerated state.

When the compression degree Cs of the silica particles is larger than 40.0%, the cohesiveness between the silica particles is high, and not only does it hardly spread uniformly on the surface of the toner particles, but also the toner having a large variation in the amount of silica adhesion tends to be obtained. As a result, the fluidity and chargeability of the toner become non-uniform, and a stable image density cannot be obtained.
When the compression degree Cs of the silica particles is less than 15.0%, the silica particles are easily loosened from the aggregated state by the impact at the time of external addition, and spread and adhere to the toner particle surfaces. However, when silica particles are present alone on the toner surface, electrostatic and non-electrostatic adhesion to the toner particle surface is weak. As a result, the toner particles may be separated from the surface of the toner particles or may be unevenly distributed and stay in the recesses. In particular, in the case of silica particles added for the purpose of the spacer effect, the effect as spacer particles cannot be obtained, and the silica particles are embedded in the toner particle surface during durability, which causes a decrease in transfer efficiency during durability.
The compression degree Cs of the silica particles is preferably 18.0% or more and 36.0% or less.
In order to set the compression degree Cs of the silica particles in the above range, the loose apparent density As and the hard apparent density Ps are preferably in the following ranges.

The loose apparent density As of the silica particles is preferably 0.15 g / cm ³ or more and 0.80 g / cm ³ or less, more preferably 0.17 g / cm ³ or more and 0.62 g / cm ³ or less, 0.21
More preferably, it is g / cm ³ or more and 0.60 g / cm ³ or less.
In the present invention, the apparent loose density of the silica particles can be adjusted by adjusting the number average particle diameter (D1). To increase this value, the number average particle diameter (D1) can be increased and decreased. For this purpose, the number average particle diameter (D1) may be reduced.
The apparent apparent density Ps of the silica particles is preferably 0.20 g / cm ³ or more and 1.00 g / cm ³ or less, more preferably 0.25 g / cm ³ or more and 0.80 g / cm ³ or less, and 0.30 g
/ Cm ³ or more and 0.75 g / cm ³ or less is more preferable.
In the present invention, the apparent density of the solidified silica particles can be adjusted by adjusting the BET specific surface area of the silica particles. To increase this value, the BET specific surface area should be decreased, and this value should be decreased. For this, the BET specific surface area may be increased.
In order to increase the value of the BET specific surface area of the silica particles, for example, it is possible to lower the flame temperature at the time of production, and conversely, to decrease it, it is possible to increase the flame temperature.

Secondly, it is important that the silica particles used in the present invention have a number average particle diameter (D1) of 0.06 μm or more and 0.20 μm or less.
When the number average particle diameter (D1) of the silica particles is within the above range, both toner fluidity and spacer effect can be obtained, and high transferability (dot reproducibility and transfer efficiency) can be obtained over a long period of time. Can be maintained. Further, it is necessary to make the compression degree Cs of the silica particles described above within a desired range.

  In order to prevent silica particles from being embedded in the toner surface and maintain durability even when the toner is stressed, it is necessary to have fine particles having a large particle size effective as a spacer on the toner surface. It is. However, large-sized fine particles generally have poor fluidity, and if they are simply externally added, it is difficult to uniformly adhere to the toner surface, and a sufficient effect as a spacer cannot be obtained.

Conventionally, it has been proposed to use a mixture of small particle size silica particles for imparting toner fluidity and large particle size silica particles as spacer particles for maintaining the durability of the toner (for example, Patent Document 2).
However, since the small particle size particles have a small particle size, the electrostatic adhesion force to the toner and the non-electrostatic adhesion property are stronger, and the particles are adhered to the toner particle surface earlier than the large particle size particles. As a result, the large particle size particles must adhere to the toner particle surface after the small particle size particles have adhered. In such a case, the adhesion of the large particle size fine particles to the toner particle surface becomes insufficient and is easily released, and the effect as a spacer cannot be obtained by long-term use.

  As described above, when a mixture of a plurality of types of particles is used, the chargeability and cohesiveness of the particles are different. In some cases, it could not be demonstrated.

  Therefore, in the toner of the present invention, by using a single type of silica particles having the specific number average particle diameter (D1), it is possible to obtain both fluidity imparting effects and spacer effect imparting effects.

When the number average particle diameter (D1) of the silica particles is larger than 0.20 μm, the particle diameter becomes too large and is easily released from the surface of the toner particles, and the transferability is likely to deteriorate during durability. Further, the cohesiveness between the silica particles becomes low, and the degree of compression Cs tends to be less than 15.0%.
When the number average particle diameter (D1) of the silica particles is less than 0.06 μm, the fluidity can be secured in the initial stage of durability, but the spacer effect cannot be obtained sufficiently, so that the silica particles are embedded in the toner particles during the durability. Become more. As a result, the fluidity of the toner changes greatly, a uniform charge cannot be obtained, and a stable image density cannot be obtained. Further, the cohesiveness between the silica particles becomes high, and the compression degree Cs tends to be larger than 40.0%.
The number average particle diameter (D1) of the silica particles is preferably 0.08 μm or more and 0.16 μm or less.
In the present invention, the number average particle diameter (D1) of the silica particles can be adjusted, for example, by classification or crushing treatment. For example, when the number average particle size is increased, the crushing strength may be decreased. When the number average particle size is decreased, the crushing strength may be increased.

Third, it is important for the toner of the present invention that P1 / P2 is 1.05 or more and 2.00 or less.
Here, a parameter defining toner P1 / P2 will be described. P1 is the abundance ratio of the wax to the binder resin between about 0.3 μm from the toner surface, and P2 is the abundance ratio of the wax to the binder resin between about 1.0 μm.

In the present invention, the presence of a large amount of wax between about 0.3 μm from the toner surface can suppress a drop in dot reproducibility in the transfer process.
In the transfer step, transfer is performed by applying a transfer pressure to the toner image visualized on the image carrier or intermediate transfer member. The toner is subjected to a shearing force by the transfer member, but if the toners compacted by the transfer pressure do not have a certain cohesiveness, the toner image may be disturbed by the shearing force and the dot reproducibility may be reduced. is there.
In the toner subjected to the transfer pressure, silica particles are embedded on the surface of the toner particles, and the toner particles come into direct contact with each other without the silica particles.
Since wax has a smaller molecular weight than that of the binder resin and is soft and has strong adhesion, the presence of a large amount of wax in the vicinity of the toner surface (between about 0.3 μm) increases the cohesiveness between the compacted toners. Can do. As a result, it is possible to suppress a drop in dot reproducibility due to a toner image being disturbed by a shearing force during transfer.

  However, when a large amount of wax is present on the toner particle surface, silica particles are easily embedded in the toner particle surface. If the degree of embedding of silica particles in the surface of the toner particles increases due to the stirring of the developer in the developing device or the peripheral rubbing with the developer carrying member, the transfer efficiency is lowered or the toner cannot obtain sufficient charge. The image density may change greatly.

  Accordingly, the present inventors have intensively studied and controlled the embedding of the silica particles on the toner particle surface by controlling the abundance ratio of the wax to the binder resin between about 1.0 μm from the toner surface. I found that I can do it. For this reason, a wax existing ratio of about 1.0 μm from the toner surface was adopted as P2. By using this as an index, a stable image density can be obtained over a long period of time.

Although the mechanism is not clear, the present inventors speculate as follows.
Since wax has a small molecular weight and is soft compared to the binder resin, if it is present in a large amount on the surface of the toner particles, silica particles are easily embedded in the surface of the toner particles due to stress. However, it is considered that the embedding of silica particles involves not only the toner particle surface layer but also the softness of the lower layer. For example, even if the wax ratio of the outermost layer of the toner particles is high, if the lower layer is composed of a hard resin layer, the silica particles are not embedded to such an extent that their functions are lost. In particular, the larger the particle size within a specific particle size range, the greater the effect of suppressing the silica particles from being embedded. As a result, even during durability, stable charge can be obtained by ensuring fluidity, so that a stable image density can be obtained.

In addition, by adopting this configuration, the release of silica particles from the toner surface can be suppressed by the wax that is present in large amounts on the toner surface. In general, silica particles are hydrophobized with methylchlorosilanes, silicone oil, or the like in order to obtain stable charging characteristics even in environments with different humidity. Since the wax is more hydrophobic than the binder resin and has good affinity with the hydrophobized silica particles, the uniformly dispersed silica particles can be held on the toner surface. In particular, the silica particles can be retained on the toner surface even on large-diameter silica particles having low cohesiveness and weak adhesion, or on the convex portion of the toner surface on which the silica particles are difficult to adhere. As a result, high transfer efficiency can be maintained even during durability.

  For the above reasons, the ratio P1 of the wax to the binder resin between about 0.3 μm from the toner surface and the ratio P2 of the wax to the binder resin between about 1.0 μm are adjusted, and P2 of the P1 is adjusted. It is necessary to control the ratio to (P1 / P2). As a result, excellent dot reproducibility and high durability can be ensured.

Specifically, the toner of the present invention uses an ATR method, and has an ATR crystal of Ge and an infrared light incident angle of 45 °, and an FT-IR spectrum obtained by measuring 2843 cm ⁻¹ or more and 2853 cm ^−1. The maximum absorption peak intensity in the following range is Pa, the maximum absorption peak intensity in the range of 1713 cm ^{−1 to} 1723 cm ⁻¹ is Pb,
In the FT-IR spectrum obtained by measurement using the ATR method under the conditions of KRS5 as the ATR crystal and 45 ° as the infrared light incident angle, the maximum absorption peak intensity in the range of 2843 cm ^{−1 to} 2853 cm ⁻¹ is Pc, the maximum absorption peak intensity of 1713 cm ^-1 or 1723 cm ^-1 following range when the Pd, characterized in that it satisfies the following relationship formula (1).

1.05 ≦ P1 / P2 ≦ 2.00 Formula (1)

In [formula (1), said maximum absorption peak intensity Pa is subtracted the mean value of the absorption peak intensity of 3050 cm ^-1 and 2600 cm ^-1 from the maximum value of the absorption peak intensity of 2843cm ^-1 or 2853cm ^-1 the range and a value, said maximum absorption peak intensity Pb is a value obtained by subtracting the mean value of the absorption peak intensity of 1763cm ^-1 and 1630 cm ^-1 from the maximum value of the absorption peak intensity of 1713 cm ^-1 or 1723 cm ^-1 or less in the range There, said maximum absorption peak intensity Pc is a value obtained by subtracting the mean value of the absorption peak intensity of 3050 cm ^-1 and 2600 cm ^-1 from the maximum value of the absorption peak intensity of 2843cm ^-1 or 2853cm ^-1 the range, the maximum absorption peak intensity Pd is the maximum value of the absorption peak intensity of 1713 cm ^-1 or 1723 cm ^-1 or less in the range 1763cm ^-1 and 1630 is a value obtained by subtracting the mean value of the absorption peak intensity at m ^-1, is P1 = Pa / Pb, P2 = Pc / Pd. ]

Absorption peak of 1713 cm ^-1 or 1723 cm ^-1 The following ranges are peaks due primarily to -CO- stretching vibration derived from the binder resin.
The peak derived from the binder resin, but out-of-plane deformation vibrations various peaks of CH aromatic rings in addition to the above is detected, the range of 1500 cm ^-1 or less, there are many peaks, binder It is difficult to separate only the resin peak, and an accurate numerical value cannot be calculated. For this reason, an absorption peak in the range of 1713 cm ⁻¹ or more and 1723 cm ⁻¹ or less that can be easily separated from other peaks is used as the peak derived from the binder resin.

Further, the absorption peak in the range of 2843cm ^-1 or 2853cm ^-1 or less, mainly -CH ₂ derived wax - a peak caused by stretching vibration (symmetric).
The peak of the wax, the peak of the in-plane bending vibration of CH ₂ in the 1500 cm ^-1 or less 1450 cm ^-1 or even other than the above is detected, will overlap with the peak derived from the binder resin, the peak of the wax It is difficult to separate. For this reason, an absorption peak in the range of 2843 cm ⁻¹ or more and 2853 cm ⁻¹ or less that can be easily separated from other peaks is used as the peak derived from the wax.

In the present invention, it has been found that the maximum absorption peak intensity (Pb, Pd) derived from the binder resin and the maximum absorption peak intensity (Pa, Pc) derived from the wax correlate with the abundance of the binder resin and the wax. Therefore, the abundance ratio of the wax to the binder resin is calculated by dividing the maximum absorption peak intensity derived from the wax by the maximum absorption peak intensity derived from the binder resin.
Here, when obtaining the Pa and Pc, why subtracting the mean value of the absorption peak intensity of 3050 cm ^-1 and 2600 cm ^-1 from the maximum value of the absorption peak intensity of 2843cm ^-1 or 2853cm ^-1 or less range, baseline This is to eliminate the influence and calculate the true peak intensity. Since there are no absorption peaks in the vicinity of 3050 cm ⁻¹ and 2600 cm ⁻¹ , the baseline intensity can be calculated by calculating the average value of these two points.

On the other hand, when obtaining the Pb and Pd, reason subtracting the mean value of the absorption peak intensity of 1763cm ^-1 and 1630 cm ^-1 from the maximum value of the absorption peak intensity of 1713 cm ^-1 or 1723 cm ^-1 or less in the range, the effect of baseline This is because the true peak intensity is calculated. Since there are no absorption peaks in the vicinity of 3050 cm ⁻¹ and 2600 cm ⁻¹ , the baseline intensity can be calculated by calculating the average value of these two points.

The abundance ratio (P1) of the wax to the binder resin between about 0.3 μm from the toner surface is ATR, Ge (n ₂ = 4.0) as the ATR crystal, and 45 as the infrared light incident angle. It is calculated from the Pa and Pb obtained by measurement under the condition of ° (P1 = Pa / Pb). Here, P1 represents the abundance ratio of the wax to the binder resin in the vicinity of the toner surface. When measuring the abundance ratio of the wax to the binder resin in the vicinity of the toner surface (that is, a distance smaller than about 0.3 μm from the toner surface), increase the incident angle of infrared light (IR) to the ATR crystal. Can be considered. However, the intensity of the IR spectrum decreases as the incident angle is increased. As a result, the numerical reliability is lowered. For this reason, the inventors measured under the condition of an incident angle of 45 °, which can ensure the intensity of the IR spectrum, and set the ratio of the wax to the binder resin between about 0.3 μm from the toner surface near the toner surface. The abundance ratio of the wax to the binder resin (P1).

Specifically, P1 is preferably 0.20 or more and 1.50 or less, and more preferably 0.30 or more and 1.20 or less.
P1 can be controlled within the above range by adjusting the type of wax and the amount of wax added to the binder resin, and by performing a toner modification process using hot air in the toner manufacturing process. For example, in order to increase P1, the surface treatment temperature with hot air is increased or the amount of added wax is increased. On the other hand, to decrease P1, the surface treatment temperature with hot air is decreased or the addition of wax is performed. It can be changed by decreasing the amount.

  On the other hand, the abundance ratio (P2) of the wax to the binder resin between about 1.0 μm from the toner surface was determined by using the ATR method, KRS5 (n2 = 2.4) as the ATR crystal, and 45 ° as the infrared light incident angle. It is calculated from the above Pc and Pd obtained by measurement under the conditions (P2 = Pc / Pd).

Specifically, P2 is preferably 0.10 or more and 0.70 or less, and more preferably 0.20 or more and 0.60 or less.
P2 can be controlled within the above range by adjusting the type of wax and the amount added to the binder resin.

In order to ensure excellent dot reproducibility and high durability, P1 / P2 is 1.05 or more and 2.00 or less, preferably 1.20 or more and 1.80 or less.
When P1 / P2 is greater than 2.00, the ratio of wax unevenly distributed in the vicinity of the toner surface is too high. In such a toner, too much wax is unevenly distributed in the vicinity of the surface, so that the external additive is easily embedded in the toner surface. As a result, the fluidity of the toner is lowered and the charge amount of the toner is changed, so that the image density at the time of endurance greatly changes.

The toner having P1 / P2 of less than 1.05 does not have very high cohesiveness between the toners compacted in the transfer process, and the toner image is disturbed by the shearing force at the time of transfer, and the dot reproducibility is lowered. Further, silica cannot be held on the toner surface, and the external additive is liberated and unevenly distributed in the recess, so that the transfer efficiency is deteriorated during the durability.
P1 / P2 can be controlled within the above range by using the means for independently controlling P1 and P2 described above.

  As described above, in the toner of the present invention, the silica particles having both the fluidity and the spacer effect are uniformly dispersed and adhered to the toner particle surface by suitably maintaining the presence state of the wax. As a result, durability stability capable of maintaining high transferability and high developability over a long period of time was obtained.

  Furthermore, in the present invention, the compression degree Cs of the silica particles, the number average particle diameter (D1), and the expression (1) relating to P1 / P2 indicating the degree of uneven distribution of the wax in the toner particles are within a specific range. It was found that these act synergistically and have excellent bending resistance.

The reason for this is not clear, but it is presumed as follows.
In the toner of the present invention, the silica particles are uniformly dispersed on the surface of the toner particles by impact such as mixing at the time of addition, and the affinity with the wax existing on the surface of the toner particles also works and adheres appropriately. ing. In the transfer step, transfer pressure is applied to the toner image, and the silica particles are uniformly embedded in the extreme surface layer of the toner particles. In the fixing step, the toner is melted by heat and fixed on the recording medium by pressure from a fixing roller or the like.
In the toner of the present invention, when the toner is melted, a filler effect due to the silica particles uniformly embedded in the extreme surface layer of the toner particles is expressed, and an extremely lower viscosity of the extreme surface layer region of the toner particles is suppressed, and recording is performed. It is considered that the adhesion to the medium surface is improved.
Further, after fixing, the toner is solidified again, and at the same time, the silica particles are fixed between the surface of the recording medium and the image, and an effect as an anchor is exhibited. Thereby, it is estimated that excellent bending resistance can be obtained.
In addition, since the low-temperature fixability of the toner of the present invention is hardly hindered by the silica particles, the filler effect by the silica particles is not excessively high, or the region where the filler effect is expressed is the extreme surface layer region. I guess it is one of the following.

  Examples of the wax used in the toner of the present invention include the following. Low molecular weight polyethylene, low molecular weight polypropylene, alkylene copolymer, hydrocarbon wax such as microcrystalline wax, paraffin wax, Fischer-Tropsch wax; oxide of hydrocarbon wax such as oxidized polyethylene wax or block copolymer thereof; Waxes mainly composed of fatty acid esters such as carnauba wax; those obtained by partially or fully deoxidizing fatty acid esters such as deoxidized carnauba wax.

  Furthermore, the following are mentioned. Saturated linear fatty acids such as palmitic acid, stearic acid and montanic acid; unsaturated fatty acids such as brassic acid, eleostearic acid and valinalic acid; stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnauvyl alcohol, seryl alcohol, Saturated alcohols such as sil alcohols; polyhydric alcohols such as sorbitol; fatty acids such as palmitic acid, stearic acid, behenic acid, montanic acid, and stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnauvyl alcohol, seryl alcohol, Esters with alcohols such as sil alcohols; Fatty acid amides such as linoleic acid amide, oleic acid amide, lauric acid amide; Methylene bis stearic acid amide, ethylene biscapric acid Saturated fatty acid bisamides such as amide, ethylene bis lauric acid amide, hexamethylene bis stearic acid amide; ethylene bis oleic acid amide, hexamethylene bis oleic acid amide, N, N 'dioleyl adipic acid amide, N, N' dioleyl Unsaturated fatty acid amides such as sebacic acid amides; aromatic bisamides such as m-xylene bis-stearic acid amide, N, N ′ distearyl isophthalic acid amide; calcium stearate, calcium laurate, zinc stearate, magnesium stearate Aliphatic metal salts such as those commonly referred to as metal soaps; waxes grafted to aliphatic hydrocarbon waxes using vinylic monomers such as styrene and acrylic acid; fatty acids such as behenic acid monoglycerides Price Partial esters of Lumpur; methyl ester compounds having hydroxyl groups obtained by hydrogenation of vegetable fats and oils.

  Among these waxes, hydrocarbon waxes such as paraffin wax and Fischer-Tropsch wax are preferable from the viewpoint of low-temperature fixability.

  The wax is preferably used in an amount of 1.0 to 20.0 parts by mass, more preferably 3.0 to 15.0 parts by mass, per 100 parts by mass of the binder resin. preferable. Further, the peak temperature of the maximum endothermic peak of the wax is preferably 50 ° C. or higher and 110 ° C. or lower because it is easy to achieve both storage stability and hot offset property of the toner.

In the silica particles of the present invention, the number ratio of silica particles having a number-based primary particle size of 0.06 μm or less is preferably 1.0% by number to 5.0% by number, more preferably 2.0% by number. More than 5.0% by number.
When the number ratio of the number-based primary particle diameter of 0.06 μm or less is in the above range, the presence of a small amount of silica having a small particle diameter can keep the fluidity of the silica particles moderate. it can. As a result, the effect as a spacer is further increased, and the transfer efficiency is less likely to be lowered even during durability.
In the present invention, the number ratio of silica particles having a primary particle diameter of 0.06 μm or less based on the number can be adjusted by classifying or crushing the silica particles. In order to increase this ratio, for example, the crushing process may be weakened, and in the case of decreasing the ratio, for example, the crushing process may be strengthened.

The silica particles of the present invention have a BET specific surface area (BET1) of preferably 10 m ² / g or more and 50 m ² / g or less, more preferably 15 m ² / g or more and 40 m ² / g or less.
When the BET specific surface area (BET1) is in the above range, adhesion to the toner particle surface can be appropriately obtained, the liberation of silica particles is suppressed during long-term use, and durability stability is further improved.

The production method of the silica particles of the present invention is not particularly limited as long as the number average particle diameter (D1) and the compression degree Cs satisfy the above ranges.
Examples of the method for producing the silica particles include the following methods. Flame melting method in which silicon compound is gasified and decomposed and melted in a flame, and gas phase method in which silicon tetrachloride is combusted at a high temperature together with a mixed gas of oxygen, hydrogen, and a diluent gas (for example, nitrogen, argon, carbon dioxide, etc.) (Fumed silica) A wet method (sol-gel silica) in which an alkoxysilane is hydrolyzed and condensed with a catalyst in an organic solvent in which water is present, and then the solvent is removed and dried from the resulting silica sol suspension.
Furthermore, a method may be used in which the silica particles obtained by the above production method have a desired number average particle diameter by classification and / or pulverization.

In order to bring the number average particle diameter (D1) and the compression degree Cs into desired ranges, the flame melting method is particularly preferably used for the silica particles of the present invention.
Specifically, by introducing a silicon compound (adjusted into a slurry if necessary) into a flame (in a reducing atmosphere), the gas is made into a silica fine particle. It is obtained by fusing silica fine particles formed in a flame so as to have a desired particle diameter, and collecting them by cooling, a bag filter or the like.
The particle size and BET specific surface area of the silica particles can be controlled by changing the concentration of the raw silicon compound, the flame temperature, and the treatment time.

  The silica particles obtained by the flame melting method are characterized in that the formed particles can exist as relatively independent particles, and the particle size distribution is broad. Due to this feature, it has intermediate properties between both sol-gel silica and fumed silica, and is suitable as the silica particles of the present invention.

  Furthermore, it is preferable that the surface of the silica particles used in the present invention is hydrophobized by surface treatment. Since the surface is hydrophobized, the affinity with the wax present on the surface of the toner particles is increased, and the release from the toner particles is more easily suppressed. Furthermore, the moisture absorption of the silica particles in a high temperature and high humidity environment is suppressed, the chargeability of the toner is increased, the toner is easily charged even during durability, and a stable image density is easily obtained.

  Examples of the surface treatment include silane coupling treatment, oil treatment, fluorine treatment, surface treatment for forming an alumina coating, and the like, and can be appropriately selected. It is also possible to select a plurality of types of surface treatments, and the order of these treatments is also arbitrary.

The silane coupling agent used for the silane coupling treatment is hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, benzyl. Dimethylchlorosilane, bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilyl acrylate, vinyldimethylacetoxysilane, dimethylethoxysilane, dimethyldimethoxysilane, diphenyldi Ethoxysilane, hexamethyldisiloxane, 1,3-divinyltetramethyldisiloxane, 1,3-diphenyltetramethyldisi Examples include loxane.

  The silane coupling agent treatment method is a dry method in which the vaporized silane coupling agent is reacted with the fine powder made into a cloud by stirring, or a wet method in which the fine powder is dispersed in a solvent and the silane coupling agent is dropped. Any of the laws can be adopted.

  As the oil treatment, silicone oil, fluorine oil, and various modified oils can be used, and examples thereof include dimethyl silicone oil, alkyl-modified silicone oil, α-methylstyrene-modified silicone oil, chlorophenyl silicone oil, and fluorine-modified silicone oil. .

The silicone oil may have a viscosity of 50 to 500 mm ² / s at 25 ° C., and the oil treatment amount is in the range of 3 parts by mass to 35 parts by mass with respect to 100 parts by mass of the silica particles. It is preferable to select by.

The toner of the present invention has a toner compression degree Ct of preferably 20.0% to 60.0%, more preferably 30.0% to 50.0%.
The toner compression degree Ct is obtained from the following equation (3).
Compression degree Ct (%) = 100 × (Pt−At) / Pt (3)
(In the formula, At is the loose apparent density (g / cm ³ ) of the toner, and Pt is the solid apparent density (g / cm ³ ) of the toner)

  As described above, in the transfer step, transfer is performed by applying a transfer pressure to the toner image developed on the image carrier or intermediate transfer member. The toner image may be consolidated by the transfer pressure, and further, a shearing force applied by the transfer member may be applied to disturb the toner image. Therefore, in order to reduce the disturbance of the toner image, it is effective to increase the degree of compression of the toner (to increase the cohesiveness between the compacted toners). However, when the degree of compression of the toner is too high, the adhesion with the transfer member becomes strong, and there is a possibility that the transfer efficiency is lowered. Therefore, in order to improve the dot reproducibility, it is effective to appropriately adjust the cohesiveness between the compacted toners.

When the toner compression degree Ct is in the above range, even in a high-speed machine especially for the POD market, it becomes easier to suppress a drop in dot reproducibility due to toner scattering without lowering transfer efficiency.
The loose apparent density At the toner is preferably not more than 0.30 g / cm ³ or more ^{0.45g / cm 3, 0.33g / cm} 3 or more 0.43 g / cm ³ or less is more preferable.
In the present invention, the loose apparent density of the toner can be adjusted by adjusting the average circularity. To increase this value, the average circularity can be increased, and to decrease the average circularity, the average circularity can be decreased. do it. The average circularity of the toner can be adjusted, for example, by using the surface treatment apparatus shown in FIG. 1. To increase the average circularity, the temperature of the hot air can be increased with respect to the conditions of the surface treatment apparatus. In order to reduce the temperature, the temperature of the hot air may be lowered.
The packed bulk density Pt toner is preferably not more than 0.55 g / cm ³ or more ^{0.75g / cm 3, 0.60g / cm} 3 or more 0.70 g / cm ³ or less is more preferable.
In the present invention, the apparent apparent density of the toner can be adjusted by adjusting the fluidity of the toner. To increase this value, the fluidity of the toner needs to be increased. It is sufficient to lower the sex. The fluidity of the toner can be adjusted by the number average particle diameter (D1) of the silica particles to be added.
1) should be reduced, and the number average particle diameter (D1) of the silica particles should be increased to lower it.

As the binder resin used in the toner of the present invention, the following polymers can be used.
For example, homopolymers of styrene such as polystyrene, poly-p-chlorostyrene, and polyvinyltoluene, and substituted products thereof; styrene-p-chlorostyrene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer , Styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl Styrenic copolymers such as ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-acrylonitrile-indene copolymer; polyvinyl chloride, phenol resin, natural modified phenol resin, natural resin modified maleic acid resin, Acrylic resin, meta Lil resins, polyvinyl acetate, silicone resins, polyester resins, polyurethane, polyamide resins, furan resins, epoxy resins, xylene resins, polyvinyl butyral, terpene resins, coumarone - indene resins, and petroleum resins.

Among these, it is preferable to use a polyester resin from the viewpoint of low-temperature fixability and chargeability.
The polyester resin preferably used in the present invention is a resin having a “polyester unit” in the binder resin chain. Specifically, the component constituting the polyester unit is a dihydric or higher alcohol. Examples of the monomer component include acid monomer components such as a divalent or higher carboxylic acid, a divalent or higher carboxylic acid anhydride, and a divalent or higher carboxylic acid ester.

  For example, polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (3.3) -2,2-bis (4- Hydroxyphenyl) propane, polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (2.0) -polyoxyethylene (2.0) -2,2-bis Alkylene oxide adducts of bisphenol A such as (4-hydroxyphenyl) propane and polyoxypropylene (6) -2,2-bis (4-hydroxyphenyl) propane, ethylene glycol, diethylene glycol, triethylene glycol, 1,2- Propylene glycol, 1,3-propylene glycol, 1,4-butanediol Neopentyl glycol, 1,4-butenediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, sorbit, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerin, 2 -Methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene and the like.

  Among them, the alcohol monomer component preferably used is the aromatic diol. In the alcohol monomer component constituting the polyester resin, the aromatic diol is preferably contained in a proportion of 80 mol% or more.

Examples of acid monomer components such as divalent or higher carboxylic acids, divalent or higher carboxylic acid anhydrides and divalent or higher carboxylic acid esters include aromatic dicarboxylic acids such as phthalic acid, isophthalic acid and terephthalic acid, or anhydrides thereof; Alkyldicarboxylic acids such as succinic acid, adipic acid, sebacic acid and azelaic acid or anhydrides thereof; succinic acid or anhydrides substituted with alkyl or alkenyl groups having 6 to 18 carbon atoms; fumaric acid, maleic acid and citracone Unsaturated dicarboxylic acids such as acids or anhydrides thereof.

  Of these, the acid monomer component preferably used is a polyvalent carboxylic acid such as terephthalic acid, succinic acid, adipic acid, fumaric acid, trimellitic acid, pyromellitic acid, benzophenone tetracarboxylic acid, or an anhydride thereof.

  The polyester resin is preferably 1 mgKOH / g or more and 20 mgKOH / g or less from the viewpoint of the stability of frictional charging.

  In addition, this acid value can be made the said range by adjusting the kind and compounding quantity of the monomer used for resin. Specifically, it can be controlled by adjusting the alcohol monomer component ratio / acid monomer component ratio and molecular weight during resin production. Moreover, it can control to make terminal alcohol react with a polyvalent acid monomer (for example, trimellitic acid) after ester condensation polymerization.

Examples of the colorant that can be contained in the toner include the following.
Examples of the black colorant include carbon black; those prepared by using a yellow colorant, a magenta colorant, and a cyan colorant and adjusting the color to black. As the colorant, a pigment may be used alone, but it is more preferable from the viewpoint of the image quality of a full-color image to improve the sharpness by using a dye and a pigment together.

  Examples of the color pigment for magenta toner include the following. C. 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: 2, 48: 3, 48: 4, 49, 50, 51, 52, 53, 54, 55, 57: 1, 58, 60, 63, 64, 68, 81: 1, 83, 87, 88, 89, 90, 112, 114, 122, 123, 146, 147, 150, 163, 184, 202, 206, 207, 209, 238, 269; I. Pigment violet 19; C.I. I. Bat red 1, 2, 10, 13, 15, 23, 29, 35.

  Examples of the magenta toner dye include the following. C. I. Solvent Red 1, 3, 8, 23, 24, 25, 27, 30, 49, 81, 82, 83, 84, 100, 109, 121; I. Disper thread 9; I. Solvent violet 8, 13, 14, 21, 27; C.I. I. Oil-soluble dyes such as Disper Violet 1, C.I. I. B. Basic Red 1, 2, 9, 12, 13, 14, 15, 17, 18, 22, 23, 24, 27, 29, 32, 34, 35, 36, 37, 38, 39, 40; I. Basic dyes such as Basic Violet 1, 3, 7, 10, 14, 15, 21, 25, 26, 27, 28.

  Examples of the color pigment for cyan toner include the following. C. I. Pigment blue 2, 3, 15: 2, 15: 3, 15: 4, 16, 17; I. Bat Blue 6; C.I. I. Acid Blue 45, a copper phthalocyanine pigment in which 1 to 5 phthalimidomethyl groups are substituted on the phthalocyanine skeleton.

  Examples of the coloring dye for cyan include C.I. I. There is Solvent Blue 70.

Examples of the color pigment for yellow include the following. C. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 23, 62, 65, 73, 74, 83, 93, 94, 95, 97, 109, 110, 111, 120, 127, 128, 129, 147, 151, 154, 155, 168, 174, 175, 176, 180, 181, 185; I. Bat yellow 1, 3, 20

  Examples of the coloring dye for yellow include C.I. I. There is Solvent Yellow 162.

  The amount of the colorant used is preferably 0.1 parts by mass or more and 30.0 parts by mass or less with respect to 100 parts by mass of the binder resin.

  The toner may contain a charge control agent as necessary. As the charge control agent contained in the toner, known ones can be used. In particular, a metal compound of an aromatic carboxylic acid that is colorless, has a high toner charging speed, and can stably maintain a constant charge amount is preferable.

Negative charge control agents include salicylic acid metal compounds, naphthoic acid metal compounds, dicarboxylic acid metal compounds, polymeric compounds having sulfonic acid or carboxylic acid in the side chain, sulfonates or sulfonated compounds in the side chain. Examples thereof include a polymer compound, a polymer compound having a carboxylate or a carboxylic acid ester in the side chain, a boron compound, a urea compound, a silicon compound, and calixarene.
Examples of the positive charge control agent include a quaternary ammonium salt, a polymer compound having the quaternary ammonium salt in the side chain, a guanidine compound, and an imidazole compound. The charge control agent may be added internally or externally to the toner particles. The addition amount of the charge control agent is preferably 0.2 parts by mass or more and 10.0 parts by mass or less with respect to 100 parts by mass of the binder resin.

The toner of the present invention contains the silica particles in the toner particles containing at least a binder resin, a colorant and a wax. In order to further improve fluidity and transferability, inorganic fine powder is used as an external additive. It may be added.
As the external additive, inorganic fine powders such as titanium oxide and aluminum oxide are preferable. The inorganic fine powder is preferably hydrophobized with a hydrophobizing agent such as a silane compound, silicone oil or a mixture thereof.
The external additive is preferably used in an amount of 0.1 to 5.0 parts by mass with respect to 100 parts by mass of the toner particles.

  For mixing the toner particles and the external additive, a known mixer such as a Henschel mixer can be used.

The toner particles and the method for producing the toner are not particularly limited, and a conventionally known production method can be used.
Here, a procedure of toner production using the pulverization method will be described.
In the raw material mixing step, as a material constituting the toner particles, a binder resin and a wax, and if necessary, other components such as a colorant and a charge control agent are weighed and mixed and mixed. Examples of the mixing apparatus include a double-con mixer, a V-type mixer, a drum-type mixer, a super mixer, a Henschel mixer, a Nauta mixer, and a mechano-hybrid.
Next, the mixed material is melt-kneaded to disperse wax or the like in the binder resin. In the melt-kneading step, a batch kneader such as a pressure kneader or a Banbury mixer, or a continuous kneader can be used. Due to the advantage of continuous production, single-screw or twin-screw extruders are the mainstream. For example, KTK type twin screw extruder (manufactured by Kobe Steel Co., Ltd.), TEM type twin screw extruder (manufactured by Toshiba Machine Co., Ltd.), PCM kneader (manufactured by Ikekai Tekko), twin screw extruder (manufactured by K.C.K. ), Co-kneader (manufactured by Buss), and kneedex (manufactured by Nippon Coke Industries).
Furthermore, the resin composition obtained by melt-kneading may be rolled with two rolls or the like and cooled with water or the like in the cooling step.

Next, the cooled product of the resin composition is pulverized to a desired particle size in the pulverization step. In the pulverization process, after coarse pulverization with a pulverizer such as a crusher, hammer mill, or feather mill, kryptron system (manufactured by Kawasaki Heavy Industries), super rotor (manufactured by Nissin Engineering Co., Ltd.), turbo mill (manufactured by Turbo Industry) ) And air jet type fine pulverizer.
Then, if necessary, classification such as elbow jet with inertia classification (manufactured by Nippon Steel & Mining), turboplex with centrifugal classification (manufactured by Hosokawa Micron), TSP separator (manufactured by Hosokawa Micron), Faculty (manufactured by Hosokawa Micron) The toner particles are obtained by classification using a machine or a sieving machine.

  The toner of the present invention has an equivalent circle diameter of 1.98 μm or more and 200 .200 measured by a flow type particle image measuring apparatus having an image processing resolution of 512 × 512 pixels (0.37 μm × 0.37 μm per pixel). The average circularity analyzed by dividing the particles of 00 μm or less into 800 in the range of circularity of 0.200 or more and 1.000 or less is preferably 0.950 or more and 0.980 or less, 0.960 As mentioned above, it is more preferable that it is 0.975 or less.

When the average circularity of the toner is within this range, it is preferable because high transfer efficiency can be maintained even when an intermediate transfer member is used.
In the present invention, after the pulverization or classification, the surface treatment of the toner using hot air controls the wax ratio in the vicinity of the toner surface, in order to suppress a decrease in durability and dot reproducibility. preferable.
In the present invention, the silica particles may be added before the surface treatment with hot air, and / or may be added after the surface treatment.

  Any surface treatment using hot air can be used as long as the surface of the toner can be melted with hot air and the toner treated with hot air can be cooled with cold air. It doesn't matter. For example, Meteoleinbo MR Type (manufactured by Nippon Pneumatic Co., Ltd.) can be used.

In the present invention, the toner is preferably obtained by obtaining the finely pulverized product, subjecting it to a surface treatment with hot air, and subsequent classification. Or you may surface-treat what was classified beforehand with a hot air.
Here, although the outline of the surface treatment method using the hot air will be described with reference to FIG. 1, it is not limited thereto. FIG. 1 is a cross-sectional view showing an example of a surface treatment apparatus used in the present invention. Specifically, after obtaining the finely pulverized product (also referred to as toner particles herein), the pulverized product is supplied to the surface treatment apparatus. The toner particles (114) supplied from the toner particle supply port (100) are accelerated by the injection air injected from the high-pressure air supply nozzle (115) and travel toward the airflow injection member (102) below the injection air. Diffusion air is ejected from the airflow ejecting member (102), and the toner particles are diffused outward by the diffusion air. At this time, the toner diffusion state can be controlled by adjusting the flow rate of the injection air and the flow rate of the diffusion air. Further, for the purpose of preventing fusion of the toner particles, a cooling jacket (106) is provided on the outer periphery of the toner particle supply port (100), the outer periphery of the surface treatment apparatus, and the outer periphery of the transfer pipe (116). In addition, it is preferable to pass cooling water (preferably antifreeze such as ethylene glycol) through the cooling jacket. On the other hand, the toner particles diffused by the diffusion air are treated on the surface of the toner particles by the hot air supplied from the hot air supply port (101). At this time, the hot air discharge temperature is preferably 100 ° C. or higher and 300 ° C. or lower, and more preferably 150 ° C. or higher and 250 ° C. or lower. When the temperature of the hot air is less than 100 ° C., the surface of the toner particles may not be melted. 30
If the temperature exceeds 0 ° C., the molten state proceeds too much, and the wax may be excessively segregated on the toner surface, or the toner particles may be coarsened or fused due to coalescence between the toner particles. .

The toner particles whose surface has been treated with hot air are cooled by cold air supplied from a cold air supply port (103) provided on the outer periphery of the upper part of the apparatus. At this time, it is preferable to introduce cold air from the second cold air supply port (104) provided on the side surface of the main body of the apparatus for the purpose of controlling the temperature distribution in the apparatus and controlling the surface state of the toner particles. The outlet of the second cold air supply port (104) can use a slit shape, a louver shape, a perforated plate shape, a mesh shape, etc., the introduction direction is horizontal to the center direction, and the direction along the apparatus wall surface depends on the purpose. Selectable.
At this time, the cold air temperature is preferably −50 ° C. or higher and 10 ° C. or lower, and more preferably −40 ° C. or higher and 8 ° C. or lower. The cold air is preferably dehumidified cold air. Specifically, the absolute moisture content of the cold air is preferably 5 g / m ³ or less. More preferably, it is 3 g / m ³ or less.

If these cold air temperatures are less than -50 ° C, the temperature inside the device will be too low, the heat treatment that is the original purpose will not be sufficiently performed, and the toner surface cannot be melted There is. When the temperature exceeds 10 ° C., the control of the hot air zone in the apparatus becomes insufficient, and the wax may be segregated excessively on the toner surface during the surface treatment.
Thereafter, the cooled toner particles are sucked by a blower and collected by a cyclone or the like through a transfer pipe (116).

  The toner of the present invention can be used as a one-component developer composed of toner alone, but is preferably used as a two-component developer containing toner and a magnetic carrier. That is, the two-component developer of the present invention is a two-component developer containing the toner of the present invention and a magnetic carrier. Here, the magnetic carrier is not particularly limited, and a known magnetic carrier can be used. Examples thereof include a carrier composed of an element selected from iron, copper, zinc, nickel, cobalt, and a manganese element alone or a composite ferrite. In addition, a magnetic substance-containing resin carrier containing a resin component on the surface of a magnetic substance-containing resin carrier core in which a magnetic substance is dispersed in the resin is also exemplified as the magnetic carrier.

  In the two-component developer of the present invention, the mixing ratio of the toner and the magnetic carrier is preferably 2 parts by mass or more and 35 parts by mass or less of the toner with respect to 100 parts by mass of the magnetic carrier. More preferably, it is as follows. By setting the toner within the above range, a stable image density can be achieved, and toner scattering can be reduced.

Methods for measuring various physical properties of the toner and raw materials will be described below.
<Method for Measuring Number Average Particle Size (D1) of Silica Particles and Number Ratio of 0.06 μm or Less>
Using a scanning electron microscope (SEM) S-4800 (Hitachi High-Technologies), the silica particles were observed, and the maximum diameter of 100 randomly selected silica particles was measured. The number average particle diameter (D1) of the silica particles was determined by averaging the maximum diameter. In addition, the number ratio of silica particles of 0.06 μm or less was calculated from the measured value of 100 obtained maximum diameters.

<Method for Measuring Silica, Toner Compression Cs, Ct>
First, a loose apparent density A (g / cm ³ ) was measured using a powder tester PT-R (manufactured by Hosokawa Micron Corporation). The sample used for the measurement was conditioned for 24 hours in an environment of 23 ° C. and 50% RH. The measurement environment was 23 ° C. and 50% RH. In the measurement, the developer was collected in a metal cup having a volume of 100 ml using a sieve having an opening of 75 μm and vibrating with an amplitude of 1 mm, and was rubbed off to make exactly 100 ml. And the loose apparent density A (g / cm ³ ) was calculated from the mass of the sample collected in the metal cup.
Next, the apparent apparent density P (g / cm ³ ) was measured. Using a sieve having an opening of 75 μm, the metallic cup was tapped 180 times up and down at an amplitude of 18 mm while supplying the sample so as to overflow from the metallic cup while vibrating at an amplitude of 1 mm. From the developer weight after tapping, the apparent apparent density P (g / cm ³ ) was calculated.
And compression degree Cs and Ct were calculated | required by the following formula, respectively.
Compression degree of silica Cs (%) = 100 × (Ps−As) / Ps
(In the formula, As is the loose apparent density (g / cm ³ ) of the silica particles, and Ps is the solid apparent density (g / cm ³ ) of the silica particles)
Toner compression degree Ct (%) = 100 × (Pt−At) / Pt
(In the formula, At is the loose apparent density (g / cm ³ ) of the toner, and Pt is the solid apparent density (g / cm ³ ) of the toner)

<Measurement method of P1 / P2 in FT-IR spectrum measured by ATR method>
FT-IR spectrum by ATR method was performed using Spectrum One (Fourier transform infrared spectroscopic analyzer) manufactured by PerkinElmer equipped with Universal ATR Sampling Accessory (Universal ATR measurement accessory).
The incident angle of infrared light was set to 45 °.
As the ATR crystal, Ge ATR crystal (refractive index = 4.0) and KRS-5 ATR crystal (refractive index = 2.4) were used.
Other conditions are as follows.
Range
Start: 4000 cm ^-1
End: 600 cm ⁻¹ (Ge ATR crystal)
400 cm ⁻¹ (ATR crystal of KRS-5)
Duration
Scan number: 16
Resolution: 4.00 cm ^-1
Advanced: With CO ₂ / H ₂ O correction

The specific measurement procedure is as follows.
P1 Calculation Method (1) A Ge ATR crystal (refractive index = 4.0) is attached to the apparatus.
(2) Set Scan type to Background, Units to EGY, and measure the background.
(3) Set Scan type to Sample and Units to A.
(4) Weigh precisely 0.01 g of toner on the ATR crystal.
(5) Pressurize the sample with the pressure arm. (Force Gauge is 90)
(6) Measure the sample.
(7) Baseline correction is performed on the obtained FT-IR spectrum by using Automatic Correction.
(8) The maximum value of the absorption peak intensity in the range from 2843 cm ^{−1 to} 2853 cm ⁻¹ is calculated. (Pa1)
(9) An average value of absorption peak intensities at 3050 cm ⁻¹ and 2600 cm ⁻¹ is calculated. (Pa2)
(10) Pa1-Pa2 = Pa.
Maximum absorption peak intensity in the range of Pa = 2843 cm ^{−1 to} 2853 cm ⁻¹ (11) The maximum value of the absorption peak intensity in the range of 1713 cm ^{−1 to} 1723 cm ⁻¹ is calculated. (Pb1)
(12) An average value of absorption peak intensities at 1763 cm ⁻¹ and 1630 cm ⁻¹ is calculated (Pb2)
(13) Pb1-Pb2 = Pb.
Pb = 1713 cm ^-1 or 1723 cm ^-1 or less at the maximum absorption peak intensity in the range (14) and Pa / Pb = P1.

Method for calculating P2 (1) A KRS-5 ATR crystal (refractive index = 2.4) is mounted on the apparatus.
(2) Weigh 0.01 g of toner on ATR crystal.
(3) Pressurize the sample with the pressure arm. (Force Gauge is 90)
(4) Measure the sample.
(5) Baseline correction is performed on the obtained FT-IR spectrum by using Automatic Correction.
(6) The maximum value of the absorption peak intensity in the range from 2843 cm ^{−1 to} 2853 cm ⁻¹ is calculated. (Pc1)
(7) The average value of the absorption peak intensities at 3050 cm ⁻¹ and 2600 cm ⁻¹ is calculated. (Pc2)
(8) Pc1-Pc2 = Pc.
Maximum absorption peak intensity in the range of Pc = 2843 cm ^{−1 to} 2853 cm ⁻¹ (9) The maximum value of the absorption peak intensity in the range of 1713 cm ^{−1 to} 1723 cm ⁻¹ is calculated. (Pd1)
(10) An average value of absorption peak intensities at 1763 cm ⁻¹ and 1630 cm ⁻¹ is calculated (Pd2)
(11) Pd1−Pd2 = Pd.
Maximum absorption peak intensity in the range of Pd = 1713 cm ^{−1 to} 1723 cm ⁻¹ (12) Pc / Pd = P2.

Calculation method of P1 / P2 P1 / P2 is calculated using P1 and P2 obtained as described above.

<Measuring method of average circularity of toner>
The average circularity of the toner is measured by a flow type particle image analyzer “FPIA-3000” (manufactured by Sysmex Corporation) under the measurement and analysis conditions during the calibration operation.
A specific measurement method is as follows. First, about 20 ml of ion-exchanged water from which impure solids are removed in advance is put in a glass container. In this, "Contaminone N" (nonionic surfactant, anionic surfactant, 10% by weight aqueous solution of neutral detergent for pH7 precision measuring instrument cleaning, made by organic builder, manufactured by Wako Pure Chemical Industries, Ltd. About 0.2 ml of a diluted solution obtained by diluting the solution with ion exchange water about 3 times by mass. Further, about 0.02 g of a measurement sample is added, and dispersion treatment is performed for 2 minutes using an ultrasonic disperser to obtain a dispersion for measurement. In that case, it cools suitably so that the temperature of a dispersion liquid may become 10 to 40 degreeC. As the ultrasonic disperser, a desktop type ultrasonic cleaner disperser (for example, “VS-150” (manufactured by VervoCrea)) having an oscillation frequency of 50 kHz and an electric output of 150 W is used. Ion exchange water is put in, and about 2 ml of the contamination N is added to the water tank.
The flow type particle image analyzer equipped with a standard objective lens (10 ×) was used for the measurement, and a particle sheath “PSE-900A” (manufactured by Sysmex Corporation) was used as the sheath liquid. The dispersion liquid prepared according to the procedure is introduced into the flow type particle image analyzer, and 3000 toner particles are measured in the total count mode in the HPF measurement mode. Then, by setting the binarization threshold at the time of particle analysis to 85% and specifying the analysis particle diameter, the number ratio (%) of particles in the range and the average circularity can be calculated. The average circularity of the toner is an equivalent circle diameter of 1.9.
The average circularity of the toner was determined from 8 μm to 39.96 μm.

In measurement, automatic focus adjustment is performed using standard latex particles (for example, “RESEARCH AND TEST PARTICLES Latex Microsphere Suspensions 5200A” manufactured by Duke Scientific) diluted with ion-exchanged water before starting the measurement. Thereafter, it is preferable to perform focus adjustment every two hours from the start of measurement.
In the examples of the present application, a flow-type particle image analyzer that has been issued a calibration certificate issued by Sysmex Corporation, which has been calibrated by Sysmex Corporation, was used. Measurement was performed under the measurement and analysis conditions when the calibration certificate was received, except that the analysis particle diameter was limited to a circle equivalent diameter of 1.98 μm or more and less than 39.69 μm.

<Measurement method of resin peak molecular weight (Mp), number average molecular weight (Mn), weight average molecular weight (Mw)>
The peak molecular weight (Mp), number average molecular weight (Mn), and weight average molecular weight (Mw) are measured by gel permeation chromatography (GPC) as follows.
First, a sample is dissolved in tetrahydrofuran (THF) at room temperature over 24 hours. A resin is used as the sample. The obtained solution is filtered through a solvent-resistant membrane filter “Maescho Disc” (manufactured by Tosoh Corporation) having a pore diameter of 0.2 μm to obtain a sample solution. The sample solution is adjusted so that the concentration of the component soluble in THF is about 0.8% by mass. Using this sample solution, measurement is performed under the following conditions.
Apparatus: HLC8120 GPC (detector: RI) (manufactured by Tosoh Corporation)
Column: Seven series of Shodex KF-801, 802, 803, 804, 805, 806, 807 (manufactured by Showa Denko KK)
Eluent: Tetrahydrofuran (THF)
Flow rate: 1.0 ml / min
Oven temperature: 40.0 ° C
Sample injection volume: 0.10 ml
In calculating the molecular weight of the sample, standard polystyrene resin (for example, trade name “TSK Standard Polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F— 10, F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500 ", manufactured by Tosoh Corporation) are used.

<Measurement of BET specific surface area of external additive>
The BET specific surface area of the external additive is measured according to JIS Z8830 (2001). A specific measurement method is as follows.
As a measuring device, an “automatic specific surface area / pore distribution measuring device TriStar 3000 (manufactured by Shimadzu Corporation)” which employs a gas adsorption method by a constant volume method as a measuring method is used. Setting of measurement conditions and analysis of measurement data are performed using dedicated software “TriStar3000 Version 4.00” attached to the apparatus, and a vacuum pump, a nitrogen gas pipe, and a helium gas pipe are connected to the apparatus. The value calculated by the BET multipoint method using nitrogen gas as the adsorption gas is defined as the BET specific surface area in the present invention.

The BET specific surface area is calculated as follows.
First, nitrogen gas is adsorbed on the external additive, and the equilibrium pressure P (Pa) in the sample cell and the nitrogen adsorption amount Va (mol · g ⁻¹ ) of the external additive at that time are measured. The relative pressure Pr, which is a value obtained by dividing the equilibrium pressure P (Pa) in the sample cell by the saturated vapor pressure Po (Pa) of nitrogen, is plotted on the horizontal axis, and the nitrogen adsorption amount Va (mol · g ⁻¹ ) is plotted on the vertical axis. The adsorption isotherm is obtained. Next, a monomolecular layer adsorption amount Vm (mol · g ⁻¹ ), which is an adsorption amount necessary for forming a monomolecular layer on the surface of the external additive, is determined by applying the following BET equation.
Pr / Va (1-Pr) = 1 / (Vm * C) + (C-1) * Pr / (Vm * C)
(Here, C is a BET parameter, which is a variable that varies depending on the measurement sample type, adsorbed gas type, and adsorption temperature.)
The BET equation is interpreted as a straight line with an inclination of (C-1) / (Vm × C) and an intercept of 1 / (Vm × C), where Pr is X axis and Pr / Va (1-Pr) is Y axis. Yes (this line is called BET plot).
Straight line slope = (C-1) / (Vm × C)
Straight line intercept = 1 / (Vm × C)
When the measured value of Pr and the measured value of Pr / Va (1-Pr) are plotted on a graph and a straight line is drawn by the least square method, the slope and intercept value of the straight line can be calculated. Vm and C can be calculated by solving the simultaneous equations of the slope and intercept using these values.
Furthermore, the BET specific surface area S (m ² / g) of the external additive is calculated from the calculated Vm and the molecular occupation cross-sectional area of the nitrogen molecule (0.162 nm ² ) based on the following formula.
S = Vm × N × 0.162 × 10 ⁻¹⁸
(N is Avogadro's number (mole- ¹ ).)

  The measurement using this apparatus follows the “TriStar 3000 Instruction Manual V4.0” attached to the apparatus, and specifically, the measurement is performed according to the following procedure.

Thoroughly weigh the tare of a dedicated glass sample cell (stem diameter 3/8 inch, volume about 5 ml) that has been thoroughly cleaned and dried. Then, about 0.1 g of an external additive is put into the sample cell using a funnel.
The sample cell containing the external additive is set in a “pretreatment device Bacrepprep 061 (manufactured by Shimadzu Corporation)” connected to a vacuum pump and a nitrogen gas pipe, and vacuum degassing is continued at 23 ° C. for about 10 hours. . During vacuum deaeration, the external additive is gradually deaerated while adjusting the valve so that the external additive is not sucked into the vacuum pump. The pressure in the cell gradually decreases with deaeration and finally becomes about 0.4 Pa (about 3 mTorr). After completion of vacuum degassing, nitrogen gas is gradually injected to return the inside of the sample cell to atmospheric pressure, and the sample cell is removed from the pretreatment device. Then, the mass of the sample cell is precisely weighed, and the accurate mass of the external additive is calculated from the difference from the tare. At this time, the sample cell is covered with a rubber plug during weighing so that the external additive in the sample cell is not contaminated by moisture in the atmosphere.
Next, a dedicated “isothermal jacket” is attached to the stem portion of the sample cell containing the external additive. Then, a dedicated filler rod is inserted into the sample cell, and the sample cell is set in the analysis port of the apparatus. The isothermal jacket is a cylindrical member having an inner surface made of a porous material and an outer surface made of an impermeable material capable of sucking liquid nitrogen to a certain level by capillary action.

  Subsequently, the free space of the sample cell including the connection tool is measured. Free space is measured by measuring the volume of the sample cell with helium gas at 23 ° C., and then measuring the volume of the sample cell after cooling the sample cell with liquid nitrogen in the same manner using helium gas. Calculated from the difference in volume. Further, the saturated vapor pressure Po (Pa) of nitrogen is automatically measured separately using a Po tube built in the apparatus.

Next, after performing vacuum deaeration in the sample cell, the sample cell is cooled with liquid nitrogen while continuing the vacuum deaeration. Thereafter, nitrogen gas is gradually introduced into the sample cell to adsorb nitrogen molecules to the toner. At this time, the adsorption isotherm described above is obtained by measuring the equilibrium pressure P (Pa) as needed, and the adsorption isotherm is converted into a BET plot. Note that the points of the relative pressure Pr for collecting data are set to a total of 6 points of 0.05, 0.10, 0.15, 0.20, 0.25, and 0.30. A straight line is drawn from the obtained measurement data by the least square method, and Vm is calculated from the slope and intercept of the straight line. Further, using the value of Vm, the BET specific surface area of the external additive is calculated as described above.

<Method for Measuring Toner Weight Average Particle Size (D4)>
The weight average particle diameter (D4) of the toner is a precision particle size distribution measuring apparatus “Coulter Counter Multisizer by pore electrical resistance method equipped with an aperture tube of 100 μm.
3 ”(registered trademark, manufactured by Beckman Coulter) and attached dedicated software“ Beckman Coulter Multisizer 3 Version 3.51 ”(manufactured by Beckman Coulter, Inc.) for measurement condition setting and measurement data analysis, Measurement was performed with 25,000 effective measurement channels, and measurement data was analyzed and calculated.
As the electrolytic aqueous solution used for the measurement, special grade sodium chloride is dissolved in ion-exchanged water so as to have a concentration of about 1% by mass, for example, “ISOTON II” (manufactured by Beckman Coulter, Inc.) can be used.

Prior to measurement and analysis, the dedicated software was set as follows.
In the “Standard measurement method (SOM) change screen” of the dedicated software, set the total count in the control mode to 50000 particles, the number of measurements is 1 and the Kd value is “standard particle 10.0 μm” (Beckman Coulter Set the value obtained using The threshold and noise level are automatically set by pressing the threshold / noise level measurement button. Also, the current is set to 1600 μA, the gain is set to 2, the electrolyte is set to ISOTON II, and the aperture tube flash after measurement is checked.
In the “pulse to particle size conversion setting screen” of the dedicated software, the bin interval is set to logarithmic particle size, the particle size bin is set to 256 particle size bin, and the particle size range is set to 2 μm or more and 60 μm or less.

The specific measurement method is as follows.
(1) About 200 ml of the electrolytic solution is placed in a glass 250 ml round bottom beaker exclusively for Multisizer 3, set on a sample stand, and the stirrer rod is stirred counterclockwise at 24 rpm. Then, dirt and bubbles in the aperture tube are removed by the “aperture flush” function of the analysis software.
(2) About 30 ml of the electrolytic aqueous solution was placed in a glass 100 ml flat bottom beaker, and "Contaminone N" (nonionic surfactant, anionic surfactant, organic builder consisting of an organic builder as a dispersant was precisely measured. About 0.3 ml of a diluted solution obtained by diluting a 10% by weight aqueous solution of a neutral detergent for washing a vessel (made by Wako Pure Chemical Industries, Ltd.) 3 times with ion-exchanged water is added.
(3) Two oscillators with an oscillation frequency of 50 kHz are incorporated in a state where the phase is shifted by 180 degrees, and placed in a water tank of an ultrasonic dispersion device “Ultrasonic Dissipation System Tetora 150” (manufactured by Nikki Bios Co., Ltd.) having an electrical output of 120 W. A fixed amount of ion-exchanged water is added, and about 2 ml of the contamination N is added to the water tank.
(4) The beaker of (2) is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. And the height position of a beaker is adjusted so that the resonance state of the liquid level of the electrolyte solution in a beaker may become the maximum.
(5) In a state where the electrolytic aqueous solution in the beaker of (4) is irradiated with ultrasonic waves, about 10 mg of toner is added to the electrolytic aqueous solution little by little and dispersed. Then, the ultrasonic dispersion process is continued for another 60 seconds. In the ultrasonic dispersion, the temperature of the water tank is appropriately adjusted so as to be 10 ° C. or higher and 40 ° C. or lower.
(6) To the round bottom beaker (1) installed in the sample stand, drop the toner aqueous solution (5) dispersed with toner using a pipette and adjust the measured concentration to about 5%. . Measurement is performed until the number of measured particles reaches 50,000.
(7) The measurement data is analyzed with the dedicated software attached to the apparatus, and the weight average particle diameter (D4) is calculated. The “average diameter” on the analysis / volume statistics (arithmetic average) screen when the graph / volume% is set with the dedicated software is the weight average particle diameter (D4).

<Peak temperature of maximum endothermic peak of wax, glass transition temperature Tg of resin>
The peak temperature of the maximum endothermic peak of the wax is measured according to ASTM D3418-82 using a differential scanning calorimeter “Q1000” (manufactured by TA Instruments). The temperature correction of the device detection unit uses the melting points of indium and zinc, and the correction of heat uses the heat of fusion of indium. Specifically, 10 mg of wax is precisely weighed, placed in an aluminum pan, and an empty aluminum pan is used as a reference. Measurement is performed at ° C / min. In the measurement, the temperature is once raised to 200 ° C., subsequently lowered to 30 ° C., and then the temperature is raised again. The maximum endothermic peak of the DSC curve in the temperature range of 30 to 200 ° C. in the second temperature raising process is defined as the maximum endothermic peak of the wax.
The glass transition temperature (Tg) of the resin is measured by precisely weighing 10 mg of the resin in the same manner as the peak temperature measurement of the maximum endothermic peak of the wax. A specific heat change is obtained in the temperature range of 40 ° C. or higher and 100 ° C. or lower. At this time, the intersection of the intermediate point line of the baseline before the specific heat change and after the specific heat change and the differential heat curve is defined as the glass transition temperature Tg of the resin.

  Specific examples of the present invention will be described below, but the present invention is not limited to these examples.

<Examples of resin production>
(Binder resin 1)
Put 50.0 parts by mass of 1,2-propylene glycol, 45.0 parts by mass of terephthalic acid, 6.0 parts by mass of adipic acid, and 0.3 parts by mass of titanium tetrabutoxide in a glass 4-liter four-necked flask. A meter, a stirring bar, a condenser, and a nitrogen introduction tube were attached and placed in a mantle heater. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was carried out for 3 hours while stirring at a temperature of 200 ° C. Furthermore, 6.5 parts by mass of trimellitic acid and 0.2 parts by mass of titanium tetrabutoxide were added, and the mixture was reacted at 190 ° C. for 3 hours to obtain a binder resin 1.
The glass transition temperature (Tg) of the binder resin 1 was 63.1 ° C., the peak molecular weight (Mp) 18,200, the number average molecular weight (Mn) 6,300, and the weight average molecular weight (Mw) 88,500.

(Binder resin 2)
72.0 parts by mass of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, 27.3 parts by mass of terephthalic acid, 0.7 parts by mass of trimellitic anhydride, and 0.4% of titanium tetrabutoxide. 5 parts by mass were placed in a 4-liter 4-neck flask made of glass, and a thermometer, a stirring rod, a condenser and a nitrogen introduction tube were attached and placed in a mantle heater. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was carried out for 2.5 hours while stirring at a temperature of 200 ° C. to obtain the binder resin 2. The binder resin 2 had a glass transition temperature (Tg) of 54.3 ° C., a peak molecular weight (Mp) of 2,300, a number average molecular weight (Mn) of 1,900, and a weight average molecular weight (Mw) of 3,200.

  Table 1 shows the glass transition temperature (Tg), peak molecular weight (Mp), number average molecular weight (Mn), and weight average molecular weight (Mw) of each binder resin.

<Example of production of silica particles>
(Silica particles)
For the production of silica particles, a hydrocarbon-oxygen mixed burner having a double tube structure capable of forming an inner flame and an outer flame was used as the combustion furnace. A two-fluid nozzle for slurry injection is grounded at the center of the burner, and a silicon compound as a raw material is introduced. A hydrocarbon-oxygen combustible gas is injected from the periphery of the two-fluid nozzle to form an inner flame and an outer flame which are reducing atmospheres. By controlling the amount and flow rate of combustible gas and oxygen, the atmosphere, temperature, flame length, and the like are adjusted. Silica fine particles are formed from the silicon compound in the flame, and further fused to a desired particle size. Then, after cooling, it is obtained by collecting with a bag filter or the like.
Silica fine particles were produced using hexamethylcyclotrisiloxane as a raw material silicon compound, and 100 parts by mass of the obtained silica fine particles were subjected to surface treatment with 4% by mass of hexamethyldisilazane and silica particles A-1. did.

  About silica particle A-2-A-10, it produced using the operation similar to the above except having changed the density | concentration of the silicon compound used as a raw material, flame concentration, and processing time.

(Sol-gel silica)
100 parts by mass of silica fine particles prepared by the sol-gel method were surface-treated with 2% by mass of hexamethyldisilazane.

(Fumed silica)
A surface treatment was performed on 1 part by mass of hexamethyldisilazane on 100 parts by mass of silica fine particles prepared by a dry method.

  Table 2 shows the loose apparent density As, the solid apparent density Ps, the degree of compression Cs, the number average particle diameter (D1), the number ratio of the number average particle diameter of 0.06 μm or less, and the BET specific surface area of the obtained silica particles. Show.

Next, an example of toner production will be described.
<Example of toner production>
(Toner Production Example 1)
-Binder resin 1 40.0 parts by mass-Binder resin 2 60.0 parts by mass-Fischer-Tropsch wax (peak temperature of maximum endothermic peak 78 ° C)
5.0 parts by mass I. Pigment Blue 15: 3 4.0 parts by mass-3,5-di-t-butylsalicylic acid aluminum compound 0.5 parts by mass After thoroughly mixing the above materials with a Henschel mixer (FM-75 type, manufactured by Mitsui Mining Co., Ltd.) The mixture was melt kneaded with a twin-screw kneader (PCM-30 type, manufactured by Ikegai Co., Ltd.) set at a temperature of 120 ° C. The obtained kneaded material was cooled and coarsely pulverized to 1 mm or less with a hammer mill to obtain a coarsely pulverized material.
Next, a 5.8 μm finely pulverized product was produced from the obtained crushed material using a turbo mill (T-250: RSS rotor / SNB liner) manufactured by Turbo Industries.
Next, the obtained finely pulverized product is classified using a particle design device (product name: Faculty) manufactured by Hosokawa Micron with improved hammer shape and number, and toner particles 1 having an average circularity of 0.944 are obtained. It was.

To 100 parts by mass of the obtained toner particles 1, 2.5 parts by mass of silica particles A-1 and 0.2 parts by mass of titanium oxide fine particles having a BET specific surface area of 180 m ² / g surface-treated with 16% by mass of isobutyltrimethoxysilane. The mixture was added, mixed with a Henschel mixer (FM-75 type, manufactured by Mitsui Mining Co., Ltd.) at a rotation speed of 30 s ⁻¹ and a rotation time of 10 min, and heat-treated by the surface treatment apparatus shown in FIG. The operating conditions were a feed amount = 5 kg / hr, a hot air temperature C = 220 ° C., and a hot air flow rate = 6 m ³ / min. Cold air temperature E = 5 ° C., cold air flow rate = 4 m ³ / min. , Cold air absolute water content = 3 g / m ³ , blower air flow = 20 m ³ / min. Injection air flow rate = 1 m ³ / min. It was. The obtained treated toner particles 1 have an average circularity of 0.964,
The weight average particle diameter (D4) was 6.3 μm.

To 100 parts by mass of the obtained treated toner particles 1, 0.2 parts by mass of titanium oxide fine particles having a BET specific surface area of 180 m ² / g surface-treated with 16% by mass of isobutyltrimethoxysilane were added, and a Henschel mixer (FM-75 type, Toner 1 was obtained by mixing at a rotational speed of 30 s ⁻¹ and a rotational time of 2 min.

In Toner 1, P1 = 0.414, P2 = 0.322, P1 / P2 = 1.33, toner loose apparent density At = 0.36 g / cm ³ , solid apparent density Pt = 0.64 g /
cm ³ , compressibility Ct = 43.8%.

(Toner Production Examples 2 to 19)
In Toner Production Example 1, toners 2 to 19 were obtained in the same manner except that the toner formulation and production conditions shown in Table 3 were changed.

  Table 4 shows physical properties of the obtained toners 1 to 19.

<Example of manufacturing magnetic carrier>
100 parts by mass of a magnetite particle having a 50% particle size (D50) of 35 μm on a volume basis, 1 part by mass of a silicone resin (manufactured by Shin-Etsu Chemical Co., Ltd .: KR271), 0.5 part by mass of γ-aminopropyltriethoxysilane, 98. 5 parts by mass of the mixed solution was added, and further dried under reduced pressure at 70 ° C. for 5 hours while stirring and mixing with a solution vacuum kneader to remove the solvent. Then, it baked at 140 degreeC for 2 hours, and sieved with the sieve shaker (300MM-2 type | mold, Tsutsui physics and chemistry machine: 75 micrometers opening), and the magnetic carrier was obtained. The carrier D50 was 37 μm.

(Examples 1 to 13, Comparative Examples 1 to 5, Reference Example 1)
Next, a two-component developer was prepared by combining the toner thus prepared and the magnetic carrier in Table 5. The two-component developer was mixed at a blending ratio of 8 parts by mass of toner with respect to 100 parts by mass of the magnetic carrier, and mixed for 5 minutes with a V-type mixer.

<Evaluation of two-component developer>
As an image forming apparatus, a digital commercial printing printer “imagePRESSSC7000VP” modified by Canon was used to form an image for evaluation. The two-component developer was evaluated by putting it in a cyan developing device of an image forming apparatus. The evaluation results are shown in Table 6.

The modified point was that an AC voltage and a DC voltage V _DC of a frequency of 10.0 kHz and Vpp of 1.7 kV were applied to the developer carrier. Then, the DC voltage _VDC was adjusted so that the amount of applied toner on the drum of a single color FFh image (solid image) was 0.45 mg / cm ² .
The transfer current value in the transfer process was adjusted as follows. Transfer current value in the first transfer process: 28 μA (normal temperature and normal humidity environment, high temperature and high humidity environment). Transfer current value in the second transfer step: 35 μA (room temperature and humidity environment), 40 μA (high temperature and humidity environment).
Printing environment: normal temperature and normal humidity environment: temperature 23 ° C / humidity 60% RH (hereinafter “N / N”)
: High temperature and high humidity environment: Temperature 30 ° C / Humidity 80% RH (hereinafter "H / H")
The FFh image is a value in which 256 gradations are displayed in hexadecimal, 00h being the first gradation of 256 gradations (white background), and FFh being the 256th gradation of 256 gradations (solid part). To do. Under the above conditions, a 50,000 sheet durability test was performed using an original document (A4) with an image ratio of 2% and an FFh image, and the following evaluations were performed.
Paper: CS-814 laser printer paper (81.4 g / m ² )
(Sold from Canon Marketing Japan Inc.)

(1) Transfer efficiency The transfer efficiency after endurance in each environment was evaluated.
As an image for evaluation, an image formed with an FFh image pattern having a size of 5 cm × 5 cm was used. This image was developed on a drum, transferred onto paper, and an unfixed image was obtained before the fixing step. The transfer efficiency was determined from the change in weight between the toner amount on the drum and the toner amount on the paper (the transfer efficiency is 100% when the entire amount of toner on the drum is transferred onto the paper).
(Evaluation criteria)
A: Transfer efficiency is 95% or more (very good)
B: Transfer efficiency is 90% or more and less than 95% (good)
C: Transfer efficiency is 80% or more and less than 90% (acceptable level in the present invention)
D: Transfer efficiency is 70% or more and less than 80% (a level unacceptable in the present invention)

(2) Change in image density after endurance The change in image density before and after endurance in each environment was evaluated.
In each environment, the development voltage was initially adjusted so that the applied amount of toner on the FFh image was 0.45 mg / cm ² . Using an X-Rite color reflection densitometer (500 series: manufactured by X-Rite), three FFh images each having a size of 5 cm × 5 cm were output, and the image density of the third sheet was measured. The difference in image density between the initial durability and after the durability was evaluated according to the following criteria.
(Evaluation criteria)
A: 0.00 or more and less than 0.05 (very good)
B: 0.05 or more and less than 0.10 (good)
C: 0.10 or more and less than 0.20 (Acceptable level in the present invention)
D: 0.20 or more (not acceptable in the present invention)

(3) Dot reproducibility The dot reproducibility before and after durability in each environment was evaluated.
A dot image (FFh image) in which one pixel is formed by one dot was created. The spot diameter of the laser beam was adjusted so that the area per dot on the paper was 20000 μm ² or more and 25000 μm ² or less. The area of 1000 dots was measured using a digital microscope VHX-500 (lens wide range zoom lens VH-Z100, manufactured by Keyence Corporation). The number average (S) of dot areas and the standard deviation (σ) of dot areas were calculated, and the dot reproducibility index was calculated by the following formula.
Dot reproducibility index (I) = σ / S × 100
(Evaluation criteria)
A: I is less than 4.0 (very good)
B: I is 4.0 or more and less than 6.0 (good)
C: I is 6.0 or more and less than 8.0 (Acceptable level in the present invention)
D: I is 8.0 or more (not acceptable in the present invention)

(4) Bending resistance The bending resistance of images in an N / N environment was evaluated.
The development voltage was initially adjusted so that the toner loading of the FFh image was 0.45 mg / cm ^2, and an FFh image having a size of 10 cm × 10 cm was output. Subsequently, the fixed image was folded in a cross shape and rubbed 5 times with a soft thin paper (for example, “Dasper”, manufactured by Ozu Sangyo Co., Ltd.) while applying a load of 4.9 kPa. As shown in FIG. 2, the toner peels off at the crossed portion, and a sample in which the background of the paper can be seen is obtained. Next, a cross section of 512 pixels was photographed with a CCD camera at a resolution of 800 pixels / inch. The threshold is set to 60%, the image is binarized, and the part where the toner is peeled is a white part, and the smaller the area ratio of the white part is, the better the bending resistance is.
The following paper was used for evaluation of bending resistance.
Paper: GF-C157 high white paper (157 g / m ² )
(Sold from Canon Marketing Japan Inc.)
(Evaluation criteria)
A: Area ratio of white part is less than 2.0% (very good)
B: The area ratio of the white part is 2.0% or more and less than 4.0% (good)
C: Area ratio of white part is 4.0% or more and less than 6.0% (acceptable level in the present invention)
D: Area ratio of white portion is 6.0% or more (not acceptable in the present invention)

100: Toner supply port, 101: Hot air supply port, 102: Airflow injection member, 103: Cold air supply port, 104: Second cold air supply port, 106: Cooling jacket, 114: Toner, 115: High pressure air supply nozzle, 116 : Transfer piping

Claims (4)

In a toner having silica particles and toner particles containing at least a binder resin, a colorant and a wax,
The number average particle diameter (D1) of the silica particles is 0.06 μm or more and 0.20 μm or less, and the degree of compression Cs is 15.0% or more and 40.0% or less,
The toner is the toner according to satisfy the relationship below following formula (1).
1.05 ≦ P1 / P2 ≦ 2.00 Formula (1)
[In Formula (1),
i) P1 = Pa / Pb
In the FT-IR spectrum of the toner obtained by measurement under the conditions of Ge as an ATR crystal and an infrared light incident angle of 45 ° using the ATR method,
Is a value obtained by subtracting the mean value of the absorption peak intensity of 2843cm ^-1 or 2853cm ^-1 3050cm ^-1 from the maximum value of the absorption peak intensity of the range and 2600 cm ^-1, the maximum endothermic peak intensity "Pa",
Is a value obtained by subtracting the mean value of the absorption peak intensity of 1713 cm ^-1 or 1723cm ^-1 1763cm ^-1 from the maximum value of the absorption peak intensity of the range and 1630 cm ^-1, the maximum endothermic peak intensity "Pb",
ii) P2 = Pc / Pd,
In the FT-IR spectrum of the toner obtained by measurement under the conditions of KRS5 as the ATR crystal and 45 ° as the infrared light incident angle using the ATR method,
Is a value obtained by subtracting the mean value of the absorption peak intensity of 2843cm ^-1 or 2853cm ^-1 3050cm ^-1 from the maximum value of the absorption peak intensity of the range and 2600 cm ^-1, the maximum endothermic peak intensity "Pc",
Is a value obtained by subtracting the mean value of the absorption peak intensity of 1713 cm ^-1 or 1723cm ^-1 1763cm ^-1 from the maximum value of the absorption peak intensity of the range and 1630 cm ^-1, the maximum endothermic peak intensity is "Pd". ]   2. The toner according to claim 1, wherein in the silica particles, the number ratio of silica particles having a primary particle diameter of 0.06 μm or less based on the number is 1.0 number% or more and 5.0 number% or less.   The toner according to claim 1, wherein the toner has a degree of compression Ct of 20.0% or more and 60.0% or less.   The toner according to claim 1, wherein a surface of the toner particles is treated with hot air.

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