JP4208785B2 - toner - Google Patents

Description

  The present invention relates to a toner used for electrophotography, an image forming method for developing an electrostatic image, and a toner used for a toner jet.

  In recent years, devices using electrophotography have begun to be used in printers for output of computers, facsimiles, etc., in addition to copying machines for copying original documents. As a result, smaller, lighter, faster, and more reliable are being sought, and machines are becoming simpler in various ways. As a result, the performance required for the toner becomes higher, and if the improvement in the performance of the toner cannot be achieved, a better machine cannot be realized.

  In particular, printers and other machines are required to be smaller in terms of energy saving and space saving in offices. At that time, the container for storing the toner is inevitably required to be small, and it is possible to print out a large number of sheets with a small amount, that is, low consumption that can cover the same image with a smaller amount of toner. Toner is needed.

  Patent Documents 1 to 4 disclose techniques for bringing the shape of a toner closer to a sphere by a manufacturing method such as a spray granulation method, a solution dissolution method, or a polymerization method. However, both of these techniques require large-scale equipment for toner production, which is not preferable in terms of production efficiency and has not yet sufficiently reduced toner consumption.

  Patent Documents 5 to 8 disclose techniques for modifying the shape and surface properties of toner produced by a pulverization method by thermal or mechanical impact. However, even if the shape of the toner is modified by these methods, it cannot be said that it is sufficient to reduce the amount of toner consumption, and there are cases in which a problem such as a decrease in developability is caused.

Japanese Patent Laid-Open No. 3-84558 JP-A-3-229268 Japanese Patent Laid-Open No. 4-1766 JP-A-4-102862 JP-A-2-87157 JP-A-10-97095 JP-A-11-149176 JP-A-11-202557

  An object of the present invention is to provide a toner that solves the above-mentioned problems of the prior art.

  An object of the present invention is to provide a toner that consumes less toner per image and can achieve a long life with a small amount of toner.

  An object of the present invention is to provide a toner having excellent developability in any environment.

  An object of the present invention is to provide a toner that does not generate sleeve negative ghosting and scattering.

  An object of the present invention is to provide a toner that does not generate blotches.

  An object of the present invention is to provide a toner having excellent transfer efficiency, fixing performance, and offset resistance.

The present invention relates to a toner composed of toner particles containing at least a binder resin and a colorant and inorganic fine particles.
The toner particles having an equivalent circle diameter of 3 μm or more and 400 μm or less measured by the flow type particle image measuring apparatus of the toner particles have an average circularity of 0.935 or more and less than 0.970, and the toner particles are measured by a scanning probe microscope. The average surface roughness is 5.0 nm or more and less than 35.0 nm,
Further, in the chromatogram obtained by gel permeation chromatography of the tetrahydrofuran-soluble matter in the toner, it has a main peak in a region having a molecular weight of 3.0 × 10 ³ or more and less than 3.0 × 10 ⁴ and a molecular weight of 5.0 ×. The present invention relates to a toner having at least one sub-peak or shoulder in a region of 10 ^{4 to} 1.0 × 10 ⁸ .

  A toner that reduces toner consumption, maintains high developability and transfer efficiency even in high-speed development under severe conditions such as high temperature, high humidity, and low temperature and low humidity, and does not cause sleeve ghosting or scattering. Can be provided.

  As a result of intensive studies, the present inventors have found that the developing characteristics of the toner can be controlled by controlling the circularity of the toner particles and controlling the surface roughness of the toner particles.

  The toner particles of the present invention have an average circularity of 0.935 or more and less than 0.970, preferably 0.935 or more and less than 0.965, more preferably 0.935 or more and 0.000 or less in toner particles having a particle size of 3 μm or more and 400 μm or less. The toner consumption per image area can be reduced by being less than 960, more preferably 0.940 or more and less than 0.955. When the circularity of the toner particles increases, the fluidity of the toner increases, so that the individual toners can move freely. The toner developed on a transfer material such as paper has a higher probability of being developed in units of toner as the toner has a higher degree of circularity, so the image height on the transfer material is lower and the toner consumption is reduced. The amount can be reduced. At this time, if the circularity of the toner particles is not sufficiently high, the toner tends to behave as an aggregate and is easily developed on the transfer material as an aggregate. In such an image, the height of the image from the transfer material becomes high, and when the same area is developed, more toner is developed than toner having excellent fluidity, and the amount of toner consumption increases. In addition, toner composed of toner particles having a high degree of circularity tends to be in a denser state in the developed image. As a result, the toner concealment ratio with respect to the transfer material is increased, and a sufficient image density can be obtained even with a small amount of toner. If the average circularity is less than 0.935, the height of the developed image becomes high and the toner consumption increases. In addition, since voids between toners increase and a sufficient concealment rate cannot be obtained even in a developed image, a larger amount of toner is required to obtain a required image density, resulting in toner consumption. Will increase. When the average circularity is 0.970 or more, the toner is coated on the sleeve non-uniformly due to excessive supply of toner on the developing sleeve, resulting in blotch.

  On the other hand, the toner of the present invention has an average circularity of 0.935 or more and less than 0.970, preferably 0.935 or more and less than 0.965, more preferably 0.935 or more and 0.000 in a toner having a particle diameter of 3 μm or more and 400 μm or less. The toner consumption per image area can be reduced by being less than 960, more preferably 0.940 or more and less than 0.955. This is because toner with a high degree of circularity is more likely to be in a dense state in the developed image, so that the concealment ratio of the toner with respect to the transfer material is high, and a sufficient image density can be obtained even with a small amount of toner. When the average circularity is less than 0.935, the toner consumption increases, and when the average circularity is 0.970 or more, blotch tends to occur.

The average circularity in the present invention is used as a simple method for quantitatively expressing the particle shape. In the present invention, the flow type particle image analyzer FPIA-2100 manufactured by Sysmex Corporation is used at 23 ° C. and 60%. Measurement is performed under the environment of RH, and particles within a circle equivalent diameter of 0.60 μm to 400 μm are measured. The circularity of the measured particle is obtained by the following equation (1), and further, the circle equivalent diameter is 3 μm to 400 μm. In the following particles, the value obtained by dividing the total circularity by the total number of particles is defined as the average circularity.
Circularity a = L ₀ / L (1)
[In the formula, L ₀ represents the perimeter of a circle having the same projection area as the particle image, and L represents the particle projection when image processing is performed at an image processing resolution of 512 × 512 (pixels of 0.3 μm × 0.3 μm). Indicates the perimeter of the image. ]

  The circularity used in the present invention is an index of the degree of unevenness of the toner particles and the toner, and indicates 1.00 when the toner particles and the toner are perfectly spherical, and the circularity becomes smaller as the surface shape becomes more complicated. Become. In addition, “FPIA-2100”, which is a measuring apparatus used in the present invention, calculates the circularity of each particle, and then calculates the average circularity by calculating the circularity of each particle. A calculation method is used in which 1.0 is divided into 61 classes and the average circularity is calculated using the center value and frequency of the division points. However, the error of the average circularity calculated by the calculation formula using the average circularity value calculated by this calculation method and the total circularity of each particle is very small and can be substantially ignored. In the present invention, for the reason of handling data such as shortening the calculation time and simplifying the calculation operation formula, the concept of the calculation formula using the sum of the circularity of each particle is used and partly changed. Such a calculation method may be used. Furthermore, the measurement device used in the present invention, “FPIA-2100”, improves the magnification of the processed particle image as compared with “FPIA1000”, which has been used to calculate the toner particles and the shape of the toner. Further, by improving the processing resolution of the captured image (256 × 256 → 512 × 512), the accuracy of toner particle and toner shape measurement is improved, thereby achieving more reliable capture of fine particles. It is. Therefore, when it is necessary to measure the shape and particle size distribution more accurately as in the present invention, the FPIA 2100 that can obtain information on the shape and particle size distribution more accurately is more useful.

As a specific measuring method, 0.1 to 0.5 ml of a surfactant, preferably alkylbenzene sulfonate, is added as a dispersing agent to 200 to 300 ml of water from which impurities in the container have been removed in advance, and a measurement sample is 0. Add about 1-0.5g. The suspension in which the sample is dispersed is dispersed with an ultrasonic oscillator for 2 minutes, and the circularity distribution of the particles is measured at a dispersion concentration of 0.2 to 1 million particles / μl. As the ultrasonic oscillator, for example, the following apparatus is used, and the following dispersion conditions are used.
UH-150 (manufactured by SMT Corporation)
OUTPUT level: 5
Constant mode

  The outline of the measurement is as follows.

  The sample dispersion is passed through a flow path (expanded along the flow direction) of a flat and flat flow cell (thickness: about 200 μm). The strobe and the CCD camera are mounted on the flow cell so as to be opposite to each other so as to form an optical path that passes through the thickness of the flow cell. While the sample dispersion is flowing, strobe light is irradiated at 1/30 second intervals to obtain an image of the particles flowing through the flow cell, so that each particle has a certain range parallel to the flow cell. Photographed as a two-dimensional image. From the area of the two-dimensional image of each particle, the diameter of a circle having the same area is calculated as the equivalent circle diameter. The circularity of each particle is calculated from the projected area of the two-dimensional image of each particle and the perimeter of the projected image using the above circularity calculation formula.

  In the present invention, the toner particle ratio of 0.6 to 3 μm is zero in the number-based particle size distribution of toner particles having an equivalent circle diameter of 0.6 to 400 μm measured by a flow type particle image measuring device. % Or more and less than 20%, preferably 0% or more and less than 17%, more preferably 1% or more and less than 15%. Toner particles having a size of 0.6 μm or more and less than 3 μm have a great influence on the developability of the toner, particularly the fog characteristics. Such a fine particle toner has an excessively high chargeability, is easily developed excessively at the time of developing the toner, and appears as fog on the image. However, in the present invention, the fog can be reduced by the small proportion of the fine particle toner.

  Further, since the toner of the present invention has a high average circularity as described above, it is easy to take a more densely packed state, so that the toner is coated thicker on the developing sleeve, and as a result, the upper layer of the toner layer on the sleeve. The charge amount is different between the lower layer and the lower layer, and when a large area image is continuously developed, a so-called sleeve negative ghost is generated, in which the image density in the second and subsequent sleeves is lower than the image density at the leading edge. There is a case. If a large amount of ultrafine powder is present in the toner particles at this time, the ultrafine powder has a higher charge amount than the other toner particles, so that an image density difference is liable to occur and the sleeve negative ghost is deteriorated. Since the amount of ultrafine powder is small, deterioration of sleeve negative ghost can be suppressed. If the particle ratio of 0.6 μm or more and less than 3 μm is 20% or more, the fog on the image increases and the sleeve negative ghost may be further deteriorated. In the toner particles of the present invention, the cumulative number of toner particles having a circularity of less than 0.960 is 20% or more and less than 70%, preferably 25% or more and less than 65%, more preferably 30% or more and less than 65%, more preferably. Is preferably 35% or more and less than 65%. The circularity of the toner particles varies depending on the individual toner particles. When the degree of circularity is different, the characteristics as toner particles are also different. Therefore, it is preferable that the ratio of toner particles having an appropriate degree of circularity is an appropriate value in order to improve the developability of the toner particles. Since the toner particles of the present invention have an appropriate degree of circularity and an appropriate degree of circularity distribution, the charge distribution of the toner particles becomes uniform and fogging can be reduced. If the cumulative number of toner particles having a circularity of less than 0.960 is less than 20%, the toner particles may deteriorate during durability. If the cumulative value of the number of toner particles having a circularity of less than 0.960 is 70% or more, the fog may be deteriorated or the image density in a high temperature and high humidity environment may be lowered.

  In the present invention, the average surface roughness of the toner particles is from 5.0 nm to less than 35.0 nm, preferably from 8.0 nm to less than 30.0 nm, and more preferably from 10.0 nm to less than 25.0 nm. Features. When the toner particles have an appropriate surface roughness, an appropriate gap is created between the toners, the fluidity of the toner can be improved, and better developability can be brought about. In particular, in the toner particles having the circularity, which is a feature of the present invention, excellent fluidity can be imparted to the toner particles by having the average surface roughness. In the toner particles of the present invention, better fluidity can be imparted to the toner when there are few ultrafine particles of less than 3 μm. That is, if there are many ultrafine particles in the toner particles, the ultrafine particles enter the concave portions of the toner surface, reducing the apparent average surface roughness of the toner, reducing the voids between the toner particles, and reducing the flow of toner more favorably. In some cases, it may interfere with imparting sex. If the average surface roughness of the toner particles is less than 5.0 nm, sufficient fluidity cannot be imparted to the toner, fading occurs and the image density decreases. When the average surface roughness of the toner particles is 35.0 nm or more, the gap between the toner particles becomes too large, and the toner scatters.

  The toner of the present invention also has an average circularity of 0.935 or more and less than 0.970 and a mean surface roughness of 10.3 in a toner having a particle diameter of 3 μm or more and 400 μm or less. It is 0 nm or more and less than 26.0 nm, preferably 12.0 nm or more and less than 24.0 nm. When the average surface roughness of the toner is less than 10.0 nm, a large number of external additive particles are embedded in the toner recesses, and sufficient fluidity cannot be imparted, fading occurs and a good image is obtained. I can't. When the average surface roughness of the toner is 26.0 nm or more, the external additive particles on the toner surface are not uniformly coated, and scattering is deteriorated due to poor charging. As described above, the toner also has an appropriate surface roughness and circularity, so that the effects of the present invention can be easily obtained.

  Further, the maximum height difference of the toner particles is 50 nm or more and less than 250 nm, preferably 80 nm or more and less than 220 nm, more preferably 100 nm or more and less than 200 nm, and better fluidity can be imparted to the toner. If the maximum height difference of the toner particles is less than 50 nm, sufficient fluidity cannot be imparted to the toner, fading may occur and the image density may decrease. If the maximum height difference of the toner particles is 250 nm or more, toner scattering may occur.

The scanning probe surface area when measured 1μm square area of the surface of the toner particles as measured by microscope 1.03 .mu.m ² or 1.33μm less than ^2, preferably 1.05 .mu.m ² or 1.30μm less than ^2, More preferably, it is 1.07 μm ² or more and less than 1.28 μm ² , and better fluidity can be imparted to the toner particles. If the surface area of the toner particles is less than 1.03 μm ² , sufficient fluidity cannot be imparted to the toner, fading may occur, and the image density may decrease. When the surface area of the toner particles is 1.33 μm ² or more, scattering may occur.

In the present invention, the average surface roughness of the toner particles and the toner, the maximum height difference of the toner particles, and the surface area are measured using a scanning probe microscope. Below, the example of a measuring method is shown.
Probe station: SPI3800N (manufactured by Seiko Instruments Inc.)
Measuring unit: SPA400
Measurement mode: DFM (resonance mode) shape image Cantilever: SI-DF40P
Resolution: Number of X data 256
Number of Y data 128

In the present invention, the area of 1 μm square of the toner particles and the toner surface is measured. The area to be measured is a 1 μm square area at the center of the toner particles and the toner surface measured with a scanning probe microscope. As the toner particles and toner to be measured, toner particles and toner equal to the weight average particle diameter (D ₄ ) measured by the Coulter counter method are selected at random, and the toner particles and toner are measured. The measured data is subjected to secondary correction. Five or more different toner particles and toners are measured, the average value of the obtained data is calculated, and the average surface roughness of the toner particles and toner, the maximum height difference of the toner particles, and the surface area are obtained.

In a toner in which an external additive is externally added to the toner particles, when the surface of the toner particles is measured using a scanning probe microscope, it is necessary to remove the external additive. A method is mentioned.
1) Put 45 mg of toner into a sample bottle and add 10 ml of methanol.
2) Disperse the sample for 1 minute with an ultrasonic cleaner to separate the external additive.
3) The toner particles and the external additive are separated by suction filtration (10 μm membrane filter). In the case of a toner containing a magnetic material, only the supernatant liquid may be separated by fixing the toner particles by applying a magnet to the bottom of the sample bottle.
4) The above 2) and 3) are performed three times in total, and the obtained toner particles are sufficiently dried at room temperature in a vacuum dryer.

  The toner particles from which the external additive has been removed are observed with a scanning electron microscope, and after confirming that the external additive has disappeared, the surface of the toner particles can be observed with a scanning probe microscope. If the external additive is not sufficiently removed, the surface of the toner particles is observed with a scanning probe microscope after repeating 2) and 3) until the external additive is sufficiently removed.

  2) As another method for removing the external additive in place of 3), there is a method of dissolving the external additive with an alkali. As the alkali, an aqueous sodium hydroxide solution is preferred.

  Each term is explained below.

・ Average surface roughness (Ra)
The centerline average roughness Ra defined in JIS B0601 is expanded to three dimensions so that it can be applied to the measurement surface. The absolute value of the deviation from the reference plane to the specified plane is averaged and expressed by the following formula.

Ｆ（Ｘ，Ｙ）：全測定データの示す面
Ｓ₀：指定面が理想的にフラットであると仮定したときの面積
Ｚ₀：指定面内のＺデータ（指定面に対して垂直方向のデータ）の平均値

F (X, Y): Surface S ₀ indicated by all measurement data: Area Z ₀ when the designated surface is assumed to be ideally flat Z ₀ : Z data in the designated surface (data perpendicular to the designated surface) ) Average value

  In the present invention, the designated surface means a measurement area of 1 μm square.

・ Maximum height difference (P-V)
The difference between the maximum and minimum values of Z data within the specified plane.

・ Surface area (S)
The surface area of the specified surface.

  Next, a toner particle manufacturing method using a surface modification step will be described as a preferred method for obtaining toner particles characterized by the present invention. Hereinafter, a surface modifying device used in the surface modifying step and a toner particle manufacturing method using the surface modifying device will be specifically described with reference to the drawings.

  In the present invention, the surface modification means smoothing the surface of the toner particles.

  FIG. 1 shows an example of a surface modification apparatus used in the present invention, and FIG. 2 shows an example of a top view of a rotor that rotates at a high speed in FIG.

  In the surface modification apparatus shown in FIG. 1, a casing, a jacket (not shown) through which cooling water or antifreeze liquid can be passed, and a surface modification means, which is in the casing and attached to the central rotating shaft, has a square shape on the upper surface. A plurality of discs or cylindrical pins 40, and a distributed rotor 36 which is a rotating body on a disk rotating at high speed, and a plurality of grooves on the surface arranged at regular intervals on the outer periphery of the distributed rotor 36 Is provided with a liner 34 (there is no need to have a groove on the liner surface), a classification rotor 31 that is a means for classifying the surface-modified raw material into a predetermined particle size, and a cold air A cold air introduction port 35 for introducing the raw material, a raw material supply port 33 for introducing the raw material to be treated, and a discharge valve 38 installed so as to be openable and closable so that the surface modification time can be freely adjusted. ,place A powder discharge port 37 for discharging the subsequent powder, and a space between the classification rotor 31 as the classification means and the dispersion rotor 36 and the liner 34 as the surface modification means are introduced into the classification means. It is composed of a front first space 41 and a cylindrical guide ring 39 which is a guide means for partitioning the particles, from which fine powder has been classified and removed by the classification means, into a second space 42 for introducing the particles into the surface modification means. ing. A gap portion between the dispersion rotor 36 and the liner 34 is a surface modification zone, and a classification rotor 31 and a rotor peripheral portion are classification zones.

  As shown in FIG. 1, the classifying rotor 31 may be installed vertically or horizontally. Further, the number of classification rotors 31 may be single as shown in FIG. 1 or plural.

  In the surface reforming apparatus configured as described above, when the raw material toner particles are introduced from the raw material supply port 33 with the discharge valve 38 closed, the introduced raw material toner particles are first drawn by a blower (not shown). Suctioned and classified by the classification rotor 31. At that time, the classified fine powder having a predetermined particle diameter or less is continuously discharged and removed out of the apparatus, and the coarse powder having a predetermined particle diameter or more passes along the inner periphery (second space 42) of the guide ring 39 by centrifugal force. The circulating flow generated by the dispersion rotor 36 is guided to the surface modification zone. The raw material guided to the surface modification zone is subjected to a surface modification treatment by receiving a mechanical impact force between the dispersion rotor 36 and the liner 34. The surface-modified particles having undergone surface modification are guided to the classification zone along the outer periphery (first space 41) of the guide ring 39 on the cold air passing through the inside of the machine. The coarse powder discharged to the outside of the machine is put into a circulating flow, returned to the surface modification zone again, and repeatedly subjected to the surface modification action. After a certain period of time, the discharge valve 38 is opened and the surface modified particles are recovered from the discharge port 37.

  In the surface modification step of the present invention, the fine powder component can be removed simultaneously with the surface modification of the toner particles. As a result, the ultrafine particles present in the toner particles do not adhere to the surface of the toner particles, and toner particles having a desired circularity, average surface roughness, and ultrafine particle amount can be obtained effectively. If fine powder cannot be removed at the same time as surface modification, there will be a large amount of ultrafine particles in the toner particles after surface modification, and mechanical and thermal effects will occur in the toner particle surface modification process. As a result, the ultrafine particle component adheres to the surface of the toner particles having an appropriate particle size. As a result, protrusions due to the adhering fine powder component are generated on the surface of the toner particles, and toner particles having a desired circularity and average surface roughness cannot be obtained.

  In the present invention, “removing the fine powder component simultaneously with the surface modification” means that the surface modification of the toner particles and the removal of the fine powder are repeatedly performed. An apparatus having processes may be used, or surface modification and fine powder removal may be performed by different apparatuses, and each process may be repeated.

  As a result of investigation by the present inventors, the surface modification time in the surface modification apparatus (= cycle time, the time from the end of the raw material supply to the opening of the discharge valve) is 5 seconds or more and 180 seconds or less, more preferably It is preferably 15 seconds or longer and 120 seconds or shorter. When the surface modification time is less than 5 seconds, the modification time is too short, and thus the surface modified toner particles may not be sufficiently obtained. Further, if the reforming time exceeds 180 seconds, the reforming time is too long, which may cause in-machine fusion due to heat generated during surface reforming and decrease in processing capacity.

  Furthermore, in the method for producing toner particles according to the present invention, it is preferable that the cold air temperature T1 introduced into the surface modifying apparatus is 5 ° C. or less. The cold air temperature T1 introduced into the surface modifying apparatus is 5 ° C. or less, more preferably 0 ° C. or less, still more preferably −5 ° C. or less, particularly preferably −10 ° C. or less, and most preferably −15 ° C. By making the following, in-machine fusion due to heat generated during surface modification can be prevented. When the cold air temperature T1 introduced into the surface reforming apparatus exceeds 5 ° C., in-machine fusion may occur due to heat generated during the surface modification.

  In addition, it is preferable that the cold air introduce | transduced in this surface modification apparatus is dehumidified from the surface of the dew condensation prevention in an apparatus. A well-known thing can be used as a dehumidifier. The supply air dew point temperature is preferably −15 ° C. or lower, and more preferably −20 ° C. or lower.

  Furthermore, in the method for producing toner particles of the present invention, the inside of the surface modifying device is provided with a jacket for cooling the inside of the apparatus, and a refrigerant (preferably cooling water, more preferably an antifreeze liquid such as ethylene glycol) is provided in the jacket. It is preferable to carry out surface modification treatment while passing through. In-machine cooling by the jacket can prevent in-machine fusion due to heat during the toner particle surface modification.

  In addition, it is preferable that the temperature of the refrigerant | coolant passed through this jacket of a surface modification apparatus shall be 5 degrees C or less. By setting the temperature of the refrigerant passed through the jacket in the surface reforming apparatus to 5 ° C. or less, more preferably 0 ° C. or less, and even more preferably −5 ° C. or less, in-machine melting due to heat generated during surface reforming is performed. Wearing can be prevented. When the temperature of the refrigerant introduced into the jacket exceeds 5 ° C., in-machine fusion may occur due to heat generated during surface modification.

  Furthermore, in the method for producing toner particles of the present invention, it is preferable that the temperature T2 behind the classification rotor in the surface modifying apparatus is 60 ° C. or less. By setting the temperature T2 behind the classification rotor in the surface reforming apparatus to 60 ° C. or less, preferably 50 ° C. or less, in-machine fusion due to heat generated during the surface modification can be prevented. When the temperature T2 behind the classification rotor in the surface reformer exceeds 60 ° C., the temperature is further affected in the surface reforming zone. Therefore, in-machine fusion is caused by heat generated during the surface reforming. There is.

  Furthermore, in the method for producing toner particles of the present invention, the minimum distance between the dispersion rotor and the liner in the surface modifying apparatus is preferably 0.5 mm to 15.0 mm, and more preferably 1.0 mm. It is preferable to be set to 10.0 mm. In addition, the rotational peripheral speed of the dispersion rotor is preferably 75 m / sec to 200 m / sec, and more preferably 85 m / sec to 180 m / sec. Further, the minimum distance between the upper part of the rectangular disk or cylindrical pin installed on the upper surface of the dispersion rotor in the surface modifying apparatus and the lower part of the cylindrical guide ring is 2.0 mm to 50 mm. 0.0 mm is preferable, and 5.0 mm to 45.0 mm is more preferable.

  In the present invention, it is preferable from the standpoint of toner particle productivity that the pulverized surfaces of the dispersion rotor and liner in the surface modifying apparatus are subjected to anti-wear treatment. In addition, the abrasion-resistant processing method is not limited at all. Further, the blade shapes of the dispersion rotor and liner in the surface modification device are not limited at all.

  In the toner particle production method of the present invention, the raw material toner particles finely divided in the vicinity of a desired particle diameter are removed to some extent by using an airflow classifier, and then the toner is produced by a surface modification device. It is preferable to perform surface modification of the particles and removal of the ultrafine powder component. By removing the fine powder in advance, the dispersion of the toner particles in the surface modifying apparatus becomes good. In particular, the fine powder component in the toner particles has a large specific surface area and a relatively high charge amount compared to other large toner particles, so it is difficult to separate from other toner particles, and it can be appropriately exceeded by a classification rotor. Although the fine powder component may not be classified, by removing the fine powder component in the toner particles in advance, the individual toner particles can be easily dispersed in the surface reforming device, and the ultra fine powder component is properly classified by the classification rotor. Toner particles having a desired particle size distribution can be obtained. In the toner from which fine powder has been removed by an airflow classifier, the cumulative value of the particle size distribution based on the number of toner particles of less than 4 μm in the particle size distribution measured using the Coulter counter method is 10% or more and less than 50%. It is preferably 15% by number or more and less than 45% by number, more preferably 15% by number or more and less than 40% by number, and the ultrafine powder component can be effectively removed by the surface modification apparatus of the present invention. Examples of the airflow classifier used in the present invention include elbow jet (manufactured by Nippon Steel Industries Co., Ltd.).

  Furthermore, in the present invention, the circularity of the toner particles and the particle ratio of 0.6 μm or more and less than 3 μm in the toner particles are further controlled by controlling the number of rotations of the dispersion rotor and the classification rotor in the surface modifying apparatus. It can be controlled to an appropriate value. In the present invention, when the wettability of toner particles with respect to a methanol / water mixed solvent is measured by the transmittance of light having a wavelength of 780 nm, the methanol concentration when the transmittance is 80% and the methanol concentration when the transmittance is 50% are obtained. It is preferable to be within the range of 35 to 75% by volume, preferably 40 to 70% by volume, more preferably 45 to 65% by volume, and more preferably 45 to 60% by volume. Toner particles having such methanol concentration-transmittance characteristics can be obtained by setting the surface modification treatment conditions to appropriate conditions using the surface modification apparatus characterized by the present invention. The exposure ratio of the raw material is appropriate, and a moderate and sharp chargeability can be provided to the toner particles. The toner particles of the present invention have an average circularity of 0.935 or more and less than 0.970, and are excellent in fluidity when used as a toner. As described above, the toner having good fluidity and a sharp charge amount distribution allows the toner to be uniformly and highly charged in the toner container, and obtains a good and stable image density even in long-term use. Can do. In particular, it works particularly effectively in an environment where the toner aggregates in a high-temperature and high-humidity environment and the fluidity is deteriorated or the charge amount tends to decrease.

  When the methanol concentration when the transmittance of toner particles is 80% and the methanol concentration when the transmittance is 50% is lower than 35% by volume, the chargeability of the toner becomes insufficient and the image density becomes inferior. There is. Further, if the methanol concentration when the transmittance is 80% and the methanol concentration when the transmittance is 50% exceed 75% by volume, the toner has high cohesiveness, and sufficient fluidity cannot be obtained. The developability in a high humidity environment may be insufficient.

  Further, the difference in concentration of the toner particles when the transmittance is 80% and the methanol concentration when the transmittance is 50% is 10% or less, preferably 7% or less, more preferably 5% or less. Is preferable, and better developability can be imparted to the toner. If the density difference exceeds 10%, the surface state of the toner becomes non-uniform, and the amount of toner that is illegally developed may increase and fog may increase.

  In the present invention, the wettability, that is, the hydrophobic property of the toner particles is measured using a methanol dropping transmittance curve. Specifically, as the measuring device, for example, a powder wettability tester WET-100P manufactured by Reska Co., Ltd. is used, and a methanol dropping transmittance curve measured under the following conditions and procedures is used. First, 70 ml of a water-containing methanol solution composed of 20 to 50% by volume of methanol and 50 to 80% by volume of water is put in a container, and 0.1 g of toner particles as a sample are precisely weighed and added thereto, and Prepare a sample solution for measuring hydrophobic properties. Next, transmittance was measured with light having a wavelength of 780 nm while continuously adding methanol to the measurement sample solution at a dropping rate of 1.3 ml / min, and the methanol dropping transmittance as shown in FIG. Create a curve. In this case, methanol is used as a titration solvent because the influence of elution of dyes, pigments, charge control agents, and the like contained in the toner particles is small, and the surface state of the toner particles can be observed more accurately.

The toner of the present invention has a main peak in a region having a molecular weight of 3.0 × 10 ³ or more and less than 3.0 × 10 ⁴ , and at least in a region having a molecular weight of 5.0 × 10 ⁴ or more and less than 1.0 × 10 ^8. It has one sub-peak or shoulder.

By having a main peak in a region having a molecular weight of 3.0 × 10 ³ or more and less than 3.0 × 10 ⁴ , preferably 1.0 × 10 ⁴ or more and less than 3.0 × 10 ⁴ , a small load at the time of toner surface modification Thus, a toner with a high degree of circularity can be obtained, and the productivity is also improved. In addition, good fixability can be provided. By having sub-peaks or shoulders in the molecular weight range of 5.0 × 10 ⁴ or more and less than 1.0 × 10 ⁸ , preferably 1.0 × 10 ^{5 to} 3.0 × 10 ⁶ , the entire toner has appropriate elasticity. Since the toner has an appropriate hardness when the toner surface is modified, an appropriate share is obtained and a desired toner shape is easily obtained. Further, the offset resistance can be improved.

  As an effect of combining the toner having the molecular weight distribution and the surface modification as in the present invention, excellent transfer efficiency can be obtained.

  The toner of the present invention has a low molecular weight component and a high molecular weight component in a well-balanced manner, and has an appropriate elasticity in the entire toner, so that raw materials such as colorants, waxes, and charge control agents are evenly distributed on the toner surface. Can be made. Since the toner surface has a uniform composition everywhere, it can have the same chargeability and a sharp charge distribution. If the toner surface composition is non-uniform, the charge distribution will be wide and non-uniform. In addition, since the toner of the present invention has an appropriate average surface roughness, there are many sites that can be contact-charged on the toner surface. At that time, a toner having a low molecular weight component and a high molecular weight component in a balanced manner as in the present invention can provide a sharp and high charge amount to the toner, and transfer properties from the photosensitive drum to the transfer material are improved. Furthermore, since it has an appropriate circularity, the photosensitive drum and the toner are easily separated.

When the molecular weight of the main peak is smaller than 3.0 × 10 ^{3, the} compatibility between the low molecular weight component and the high molecular weight component becomes poor, the toner surface composition becomes non-uniform, and a sharp charge distribution cannot be obtained, resulting in a decrease in transfer efficiency. To do. When the molecular weight of the main peak is 3.0 × 10 ⁴ or more, a fixing defect occurs, and the load during the surface modification treatment increases and the productivity also decreases. When the molecular weight of the sub-peak or shoulder is smaller than 5.0 × 10 ⁴ , the offset resistance performance is inferior. When the molecular weight of the sub-peak or shoulder is 1.0 × 10 ⁸ or more, the compatibility between the low molecular weight component and the high molecular weight component is deteriorated, the toner surface composition becomes non-uniform, and a sharp charge distribution cannot be obtained, resulting in transfer efficiency. descend.

  In the present invention, by using a binder resin having an acid value, the charging ability of the toner is more emphasized, the toner can be quickly charged, and a high charge amount can be imparted. It is preferable that the low molecular weight component or the high molecular weight component in the binder resin has oxidation and the acid value is 0.5 to less than 30 mgKOH / g. Furthermore, it is preferable to have an acid value on both the low molecular weight component and the high molecular weight side. In particular, the acid value of the low molecular weight component is preferably large.

In the present invention, the THF soluble content of the toner and the acid value (JIS acid value) of the raw material binder resin are determined by the following method. The acid value of the raw material binder resin also means the acid value of the THF soluble part of the raw material resin.

Basic operation conforms to JIS K-0070.
(1) The sample is used by removing the THF-insoluble content of the toner and the raw material binder resin in advance, or the soluble component extracted by the THF solvent by the Soxhlet extractor obtained by the above-mentioned measurement of the THF-insoluble content is used as the sample. use. The pulverized sample 0.5 to 2.0 (g) is precisely weighed, and the weight of the soluble component is defined as W (g).
(2) A sample is put into a 300 ml beaker, and 150 ml of a toluene / ethanol (4/1) mixed solution is added and dissolved.
(3) Titration using a potentiometric titration apparatus with an ethanol solution of 0.1 mol / l KOH (for example, potentiometric titration apparatus AT-400 (winworkstation) manufactured by Kyoto Electronics Co., Ltd. and ABP-410 electric burette Automatic titration with can be used.)
(4) The amount of KOH solution used at this time is S [ml]. At the same time, a blank test without using a sample is performed, and the amount of KOH solution used at this time is B [ml].
(5) The acid value is calculated by the following formula. f is a factor of KOH.
Acid value (mgKOH / g) = {(SB) × f × 5.61} / W

  As the types of binder resins used in the present invention, styrene resins, styrene copolymer resins, polyester resins, polyol resins, polyvinyl chloride resins, phenol resins, natural modified phenol resins, natural resin modified maleic resins, Examples thereof include acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin, polyurethane resin, polyamide resin, furan resin, epoxy resin, xylene resin, polyvinyl butyral, terpene resin, coumarone indene resin, and petroleum resin.

  As a comonomer for the styrene monomer of the styrene copolymer, a styrene derivative such as vinyltoluene; acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, acrylic Acrylic acid ester such as phenyl acid; Methacrylic acid ester such as methacrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate, octyl methacrylate; Maleic acid; Double such as butyl maleate, methyl maleate, dimethyl maleate Dicarboxylic acid ester having a bond; acrylamide, acrylonitrile, methacrylonitrile, butadiene; vinyl ester such as vinyl chloride, vinyl acetate, vinyl benzoate; ethylene, propylene, butylene Such ethylenic olefins, vinyl methyl ketone, such as vinyl vinyl hexyl ketone, vinyl methyl ether, vinyl ethyl ether, vinyl propionate ether. These vinyl monomers are used alone or in combination of two or more.

  In the present invention, a styrene-acrylic acid ester-acrylic acid copolymer, a styrene-acrylic acid ester copolymer, and a styrene-acrylic acid ester-methacrylic acid copolymer are used as a particularly preferable binder resin, whereby toner It becomes easy to control the circularity of the particles to an appropriate value.

  The binder resin used in the present invention has a glass transition temperature (Tg) of 45 to 80 ° C, preferably 50 to 70 ° C, from the viewpoint of storage stability. When Tg is lower than 45 ° C., it tends to cause toner deterioration under a high temperature atmosphere and offset during fixing. On the other hand, when Tg exceeds 80 ° C., fixability tends to decrease.

・ Glass transition point (Tg)
The temperature at the intersection of the DSC curve and the line connecting the midpoints of the baseline before and after the change in specific heat appears in the DSC curve during temperature rise.

  The measuring method of Tg is performed according to ASTM D3418-82 using Q-1000 manufactured by TA Instruments. The DSC curve used in the present invention is a DSC curve measured when the temperature is raised at a rate of 10 ° C./min after raising and lowering the temperature once and taking a previous history. The definition is as follows.

  In the present invention, the molecular weight distribution of the binder resin by GPC using THF (tetrahydrofuran) as a solvent is measured under the following conditions.

The column is stabilized in a 40 ° C. heat chamber. Tetrahydrofuran (THF) is allowed to flow through the column at this temperature as a solvent at a flow rate of 1 ml per minute, and about 100 μl of a sample THF solution is injected and measured. In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value of a calibration curve prepared from several types of monodisperse polystyrene standard samples and the number of counts. As a standard polystyrene sample for preparing a calibration curve, for example, a standard polystyrene sample having a molecular weight of about 102 to 107 manufactured by Tosoh Corporation or Showa Denko is used, and at least about 10 standard polystyrene samples are suitably used. An RI (refractive index) detector is used as the detector. As the column, it is preferable to combine a plurality of commercially available polystyrene gel columns. For example, combinations of shodex GPC KF-801, 802, 803, 804, 805, 806, 807, 800P manufactured by Showa Denko KK, TSKgel G1000H (H _XL ), G2000H (H _XL ), G3000H (H _XL ) manufactured by Tosoh Corporation , G4000H (H _XL ), G5000H (H _XL ), G6000H (H _XL ), G7000H (H _XL ), and TSK guard column.

  The sample is prepared as follows.

  Put the sample in THF, let stand for several hours, then shake well and mix well with THF (until the sample is no longer united), and let stand for more than 12 hours. At this time, the sample is left in THF for 24 hours or longer. Thereafter, a sample processing filter (pore size 0.45 to 0.5 μm, for example, Mysori Disc H-25-5 manufactured by Tosoh Corporation, Excro Disc 25CR manufactured by Gelman Science Japan Co., Ltd., etc.) can be used. A measurement sample for GPC is used. The sample concentration is adjusted so that the resin component is 0.5 to 5 mg / ml.

  Examples of the polymerization method of the binder resin of the present invention include a solution polymerization method, an emulsion polymerization method and a suspension polymerization method.

  The binder resin used in the present invention is preferably produced by using a polyfunctional polymerization initiator alone or in combination with a monofunctional polymerization initiator as exemplified below.

  Specific examples of the polyfunctional polymerization initiator having a polyfunctional structure include 1,1-di-t-butylperoxy-3,3,5-trimethylcyclohexane, 1,3-bis- (t-butylperoxy Isopropyl) benzene, 2,5-dimethyl-2,5- (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di- (t-butylperoxy) hexane, tris- (t-butyl) Peroxy) triazine, 1,1-di-t-butylperoxycyclohexane, 2,2-di-t-butylperoxybutane, 4,4-di-t-butylperoxyvaleric acid-n-butyl ester , Di-t-butylperoxyhexahydroterephthalate, di-t-butylperoxyazelate, di-t-butylperoxytrimethyladipate, 2,2-bis- ( , 4-di-t-butylperoxycyclohexyl) propane, 2,2-t-butylperoxyoctane and functional groups having a polymerization initiation function such as two or more peroxide groups in one molecule of various polymer oxides. A polyfunctional polymerization initiator having a peroxide group in one molecule such as diallyl peroxydicarbonate, t-butylperoxymaleic acid, t-butylperoxyallylcarbonate and t-butylperoxyisopropyl fumarate. Such a polyfunctional polymerization initiator having both a functional group having a polymerization initiating function and a polymerizable unsaturated group is selected.

  Of these, more preferred are 1,1-di-t-butylperoxy-3,3,5-trimethylcyclohexane, 1,1-di-t-butylperoxycyclohexane, di-t-butylperoxy. Hexahydroterephthalate, di-t-butylperoxyazelate, 2,2-bis- (4,4-di-t-butylperoxycyclohexyl) propane, and t-butylperoxyallyl carbonate.

  These polyfunctional polymerization initiators are preferably used in combination with a monofunctional polymerization initiator in order to satisfy various performances required as a binder for toner. In particular, it is preferable to use in combination with a polymerization initiator having a half-life of 10 hours lower than the decomposition temperature for obtaining a half-life of 10 hours of the polyfunctional polymerization initiator.

  Specifically, benzoyl peroxide, 1,1-di (t-butylperoxy) -3,3,5-trimethylcyclohexane, n-butyl-4,4-di (t-butylperoxy) valerate, dichroic Organic peroxides such as milperoxide, α, α'-bis (t-butylperoxydiisopropyl) benzene, t-butylperoxycumene, di-t-butylperoxide; azobisisobutyronitrile, diazoamino Examples include azo and diazo compounds such as azobenzene.

  These monofunctional polymerization initiators may be added to the monomer at the same time as the polyfunctional polymerization initiator, but in order to keep the efficiency of the polyfunctional polymerization initiator appropriate, in the polymerization step, It is preferably added after the half-life indicated by the polyfunctional polymerization initiator has elapsed.

  These polymerization initiators are preferably used in an amount of 0.05 to 2 parts by mass with respect to 100 parts by mass of the monomer from the viewpoint of efficiency.

  It is also preferable that the binder resin is crosslinked with a crosslinking monomer.

  As the crosslinkable monomer, a monomer having two or more polymerizable double bonds is mainly used. Specific examples include aromatic divinyl compounds (eg, divinylbenzene, divinylnaphthalene, etc.); diacrylate compounds linked by alkyl chains (eg, ethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4 -Butanediol diacrylate, 1,5-pentanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, and acrylates of the above compounds replaced with methacrylate); alkyl chain containing an ether bond Diacrylate compounds (eg, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol # 400 diacrylate, Ethylene glycol # 600 diacrylate, dipropylene glycol diacrylate, and acrylates of the above compounds in place of methacrylate); diacrylate compounds linked by a chain containing an aromatic group and an ether bond (eg, polyoxyethylene) (2) -2,2-bis (4-hydroxyphenyl) propane diacrylate, polyoxyethylene (4) -2,2-bis (4-hydroxyphenyl) propane diacrylate, and methacrylates of the above compounds Furthermore, polyester-type diacrylate compounds (for example, trade name MANDA (Nippon Kayaku)) are mentioned. As polyfunctional crosslinking agents, pentaerythritol acrylate, trimethylol ethane triacrylate, trimethylol propane triacrylate, tetramethylol propane triacrylate, tetramethylol methane tetraacrylate, oligoester acrylate, and acrylates of the above compounds are replaced with methacrylate. Triallyl cyanurate, triallyl trimellitate; and the like.

  These crosslinking agents are preferably used in the range of 0.00001 to 1 part by mass, preferably 0.001 to 0.05 part by mass, with respect to 100 parts by mass of the other monomer components.

  As a method for producing a binder resin composition, a high-molecular weight polymer and a low-molecular weight polymer are separately synthesized by a solution polymerization method, mixed in a solution state, and then desolvated, and an extruder. The resin composition is prepared by dissolving in a monomer constituting a high molecular weight polymer obtained by dissolving a low molecular weight polymer obtained by a melt blending method such as a melt blending method, a solution polymerization method, etc., and performing suspension polymerization, washing and drying. And a two-stage polymerization method for obtaining However, the dry blend method has a point to be improved in terms of uniform dispersion and compatibility. The two-stage polymerization method has many advantages such as uniform dispersibility, but the low molecular weight can be increased to higher than the high molecular weight, and a high molecular weight polymer with a large molecular weight can be synthesized. The solution blending method is most suitable because there are few problems that coalescence is formed as a by-product. In addition, when a predetermined acid value is introduced into the low molecular weight polymer component, solution polymerization in which the acid value can be easily set as compared with the polymerization method using an aqueous medium is preferable.

  In the present invention, the THF soluble content of the toner and the acid value (JIS acid value) of the raw material binder resin are determined by the following method. The acid value of the raw material binder resin also means the acid value of the THF soluble part of the raw material resin.

Basic operation conforms to JIS K-0070.
(1) The sample is used by removing the THF-insoluble content of the toner and the raw material binder resin in advance, or the soluble component extracted by the THF solvent by the Soxhlet extractor obtained by the above-mentioned measurement of the THF-insoluble content is used as the sample. use. The pulverized sample 0.5 to 2.0 (g) is precisely weighed, and the weight of the soluble component is defined as W (g).
(2) A sample is put into a 300 ml beaker, and 150 ml of a toluene / ethanol (4/1) mixed solution is added and dissolved.
(3) Titration using a potentiometric titration apparatus with an ethanol solution of 0.1 mol / l KOH (for example, potentiometric titration apparatus AT-400 (winworkstation) manufactured by Kyoto Electronics Co., Ltd. and ABP-410 electric burette Automatic titration with can be used.)
(4) The amount of KOH solution used at this time is S [ml]. At the same time, a blank test without using a sample is performed, and the amount of KOH solution used at this time is B [ml].
(5) The acid value is calculated by the following formula. f is a factor of KOH.
Acid value (mgKOH / g) = {(SB) × f × 5.61} / W

  The toner of the present invention preferably contains a charge control agent.

  Examples of the toner that controls the negative charge include the following compounds.

  For example, organometallic complexes and chelate compounds are effective, and there are monoazo metal complexes, acetylacetone metal complexes, aromatic hydroxycarboxylic acids, and aromatic dicarboxylic acid metal complexes. Others include aromatic hydroxycarboxylic acids, aromatic mono and polycarboxylic acids and their metal salts, anhydrides, esters, and phenol derivatives such as bisphenol.

  Among these, an azo metal complex represented by the following general formula (1) is preferable.

  In particular, the central metal is preferably Fe, the substituent is preferably a halogen, an alkyl group or an anilide group, and the counter ion is preferably hydrogen, an alkali metal, ammonium or aliphatic ammonium. A mixture of complex salts having different counter ions is also preferably used.

  Alternatively, a basic organic acid metal complex represented by the following general formula (2) is also preferable as a charge control agent that imparts negative chargeability.

  In particular, Fe, Cr, Si, Zn or Al is preferred as the central metal, alkyl groups, anilide groups, aryl groups and halogens are preferred as substituents, and hydrogen, ammonium and aliphatic ammonium are preferred as counter ions.

  The following compounds are used to control the toner to be positively charged.

  Modifications with nigrosine and fatty acid metal salts; quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate, and onium salts such as phosphonium salts thereof And these lake pigments, triphenylmethane dyes and these lake pigments (as rake agents, phosphotungstic acid, phosphomolybdic acid, phosphotungsten molybdate, tannic acid, lauric acid, gallic acid, ferricyanide, ferrocyanide) Metal salts of higher fatty acids; diorganotin oxides such as dibutyltin oxide, dioctyltin oxide, dicyclohexyltin oxide; dibutyltin borate, dioctyltin borate, dicyclohexyl Such diorgano tin borate of Suzuboreto; guanidine compounds, imidazole compounds. These can be used alone or in combination of two or more. Among these, triphenylmethane compounds and quaternary ammonium salts whose counter ions are not halogen are preferably used. Moreover, general formula (3)

［式中、Ｒ₁はＨ又はＣＨ₃を示し、Ｒ₂及びＲ₃は置換または未置換のアルキル基（好ましくはＣ₁〜Ｃ₄）を示す。］
で表わされるモノマーの単重合体：前述したスチレン、アクリル酸エステル、メタクリル酸エステルの如き重合性モノマーとの共重合体を正荷電性制御剤として用いることができる。この場合これらの荷電制御剤は、結着樹脂（の全部または一部）としての作用をも有する。

[Wherein R ₁ represents H or CH ₃ , and R ₂ and R ₃ represent a substituted or unsubstituted alkyl group (preferably C _{1 to} C ₄ ). ]
Monomers of monomers represented by: A copolymer with a polymerizable monomer such as styrene, acrylic acid ester or methacrylic acid ester described above can be used as a positive charge control agent. In this case, these charge control agents also have an action as a binder resin (all or a part thereof).

  In particular, a compound represented by the following general formula (4) is preferred as the positive charge control agent of the present invention.

  Specific product names include nigrosine dyes, metal salts of naphthenic acid or higher fatty acids, alkoxylated amines, quaternary ammonium salt compounds, azo metal complexes, salicylic acid metal salts or metal complexes thereof.

  Preferred for negative charging are, for example, Spiron Black TRH, T-77, T-95 (Hodogaya Chemical), BONTRON (registered trademark) S-34, S-44, S-54, E-84, E- 88, E-89 (Orient Chemical Co., Ltd.), and preferable examples for positive charging include TP-302, TP-415 (Hodogaya Chemical Co., Ltd.), BONTRON (registered trademark) N-01, N- 04, N-07, P-51 (Orient Chemical), and Copy Blue PR (Clariant).

  As a method for adding the charge control agent to the toner, there are a method of adding the toner inside the toner particles and a method of adding the toner outside the toner particles. The amount of use of these charge control agents is determined by the toner production method including the type of binder resin, the presence or absence of other additives, and the dispersion method, and is not uniquely limited. Preferably, it is used in the range of 0.1 to 10 parts by mass, more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the binder resin.

  The toner of the present invention may contain a wax. The waxes used in the present invention include the following. For example, paraffin wax and derivatives thereof, montan wax and derivatives thereof, microcrystalline wax and derivatives thereof, Fischer-Tropsch wax and derivatives thereof, polyolefin wax and derivatives thereof, carnauba wax and derivatives thereof, and the like. Derivatives include oxides, block copolymers with vinyl monomers, and graft modified products.

  Specific examples of the wax include Biscol (registered trademark) 330-P, 550-P, 660-P, TS-200 (Sanyo Chemical Industries), high wax 400P, 200P, 100P, 410P, 420P, 320P, 220P, 210P, 110P (Mitsui Chemicals), Sasol H1, H2, C80, C105, C77 (Schumann-Sasol), HNP-1, HNP-3, HNP-9, HNP-10, HNP-11, HNP- 12 (Nippon Seiki Co., Ltd.), Unilin (registered trademark) 350, 425, 550, 700, Unicid (registered trademark), Unicid (registered trademark) 350, 425, 550, 700 (Toyo Petrolite Co., Ltd.), Kirou, Beeswax, rice wax, candelilla wax, carnauba wax (available at Celerica NODA Inc.) And the like.

  In the toner of the present invention, the total content of these waxes is 0.1 to 15 parts by mass, preferably 0.5 to 12 parts by mass with respect to 100 parts by mass of the binder resin. It is.

  These waxes have a melting point of 65 ° C. or higher and lower than 130 ° C., preferably 70 ° or higher and lower than 120 ° C., more preferably 70 ° C. or higher and lower than 110 ° C., more preferably measured using a differential thermal analyzer (DSC). It is preferable that it is 75 degreeC or more and less than 100 degreeC. The wax having such a melting point in the toner particles has an appropriate hardness, and the toner particles having the desired circularity, particle size distribution, and surface roughness are effectively removed in the surface modification process of the toner particles. Obtainable. When the melting point of the wax is less than 65 degrees, the storage stability of the toner may be deteriorated. When the melting point of the wax exceeds 130 ° C., the toner particles become too hard and the productivity of the surface-modified toner may deteriorate.

<Measurement method of melting point of wax>
Sample: 0.5-2 mg, preferably 1 mg
Measurement method: Place the sample in an aluminum pan, and use an empty aluminum pan as a reference.
Temperature curve: Temperature increase I (20 ° C. to 180 ° C., temperature increase rate 10 ° C./min)
Temperature drop I (180 ° C to 10 ° C, temperature drop rate 10 ° C / min)
Temperature increase II (10 ° C to 180 ° C, temperature increase rate 10 ° C / min)

  The endothermic peak temperature measured at the temperature elevation II in the temperature curve is defined as the melting point.

  When the toner of the present invention contains a magnetic material, the magnetic material can also serve as a colorant. Magnetic materials used in the toner include iron oxides such as magnetite, hematite, and ferrite; metals such as iron, cobalt, and nickel or these metals and aluminum, cobalt, copper, lead, magnesium, tin, zinc, antimony, Examples include alloys with metals such as beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, vanadium, and mixtures thereof.

These magnetic materials preferably have a number average particle diameter of 0.05 to 1.0 μm, more preferably 0.1 to 0.5 μm. A magnetic substance having a BET specific surface area of ² to 40 m ² / g (more preferably 4 to 20 m ² / g) is preferably used. There is no restriction | limiting in particular in a shape, The thing of arbitrary shapes is used. As magnetic characteristics, a saturation magnetization is 10 to 200 Am ² / kg (more preferably 70 to 100 Am ² / kg) under a magnetic field of 795.8 kA / m, and a residual magnetization is 1 to 100 Am ² / kg (more preferably ² to 20 Am). ² / kg) and a coercive force of 1 to 30 kA / m (more preferably 2 to 15 kA / m) are preferably used. These magnetic materials are used in an amount of 20 to 200 parts by mass with respect to 100 parts by mass of the binder resin. Preferably it is used at 40 to 150 parts by mass.

  The number average diameter can be obtained by measuring a photograph taken with a transmission electron microscope or the like with a digitizer or the like. The magnetic properties of the magnetic material can be measured under an external magnetic field of 795.8 kA / m using a “vibrating sample magnetometer VSM-3S-15” (manufactured by Toei Kogyo Co., Ltd.). The specific surface area can be calculated by using the BET multipoint method by adsorbing nitrogen gas to the sample surface using a specific surface area measuring device Auto Soap 1 (manufactured by Yuasa Ionics Co., Ltd.) according to the BET method.

  Other colorants that can be used in the toner of the present invention include any suitable pigment or dye. Examples of the pigment include carbon black, aniline black, acetylene black, naphthol yellow, Hansa yellow, rhodamine lake, alizarin lake, Bengala, phthalocyanine blue, and indanthrene blue. These are used in an amount necessary and sufficient to maintain the optical density of the fixed image, and an addition amount of 0.1 to 20 parts by mass, preferably 0.2 to 10 parts by mass is good with respect to 100 parts by mass of the binder resin. . Examples of the dye include azo dyes, anthraquinone dyes, xanthene dyes, and methine dyes. The addition amount of the dye is 0.1 to 20 parts by mass, preferably 0.3 to 10 parts by mass with respect to 100 parts by mass of the binder resin.

  The toner particles of the present invention are preferably externally added with inorganic fine powder or hydrophobic inorganic fine powder. For example, silica fine powder, titanium oxide fine powder, or a hydrophobized product thereof can be used. They are preferably used alone or in combination.

  Examples of the silica fine powder include both a dry process produced by vapor phase oxidation of a silicon halogen compound or dry silica called fumed silica, and wet silica produced from water glass or the like. Dry silica with fewer silanol groups on the surface and inside and no production residue is preferred.

  Further, the silica fine powder is preferably hydrophobized. The hydrophobizing treatment is applied by chemically treating with an organosilicon compound that reacts or physically adsorbs with silica fine powder. Preferable methods include a method in which a dry silica fine powder produced by vapor phase oxidation of a silicon halogen compound is treated with a silane compound or with a silane compound and simultaneously with an organosilicon compound such as silicone oil.

  The silane compounds used for the hydrophobization treatment include hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, benzyldimethyl. Chlorosilane, bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilane mercaptan, trimethylsilyl mercaptan, triorganosilyl acrylate, vinyldimethylacetoxysilane, dimethylethoxysilane , Dimethyldimethoxysilane, diphenyldiethoxysilane, hexamethyldisiloxane, 1,3-divinyltetramethyldi Examples thereof include siloxane and 1,3-diphenyltetramethyldisiloxane.

Examples of the organosilicon compound include silicone oil. As a preferable silicone oil, one having a viscosity at 25 ° C. of about 30 to 1,000 mm ² / s is used. For example, dimethyl silicone oil, methylphenyl silicone oil, α-methylstyrene modified silicone oil, chlorophenyl silicone oil, and fluorine modified silicone oil are preferred.

  Silicone oil treatment can be performed by directly mixing silica powder treated with a silane compound and silicone oil using a mixer such as a Henschel mixer, or spraying silicone oil onto the base silica. It may be by the method. Alternatively, the silicone oil may be dissolved or dispersed in an appropriate solvent, and then mixed with the base silica fine powder to remove the solvent.

  As a preferable hydrophobizing treatment of the silica fine powder, there is a method of preparing by treating with hexamethyldisilazane and then treating with silicone oil.

  As described above, it is preferable to treat the silica fine powder with the silane compound and then oil-treat it later, so that the degree of hydrophobicity can be effectively increased.

  The silica fine powder is preferably subjected to a hydrophobization treatment, and further, an oil treatment applied to the titanium oxide fine powder, similarly to the silica-based one.

  To the toner particles of the present invention, additives other than silica fine powder or titanium oxide fine powder may be externally added as necessary.

  Examples thereof include resin fine particles and inorganic fine particles that act as charging aids, conductivity imparting agents, fluidity imparting agents, anti-caking agents, mold release agents at the time of hot roll fixing, lubricants, and abrasives.

  The fine resin particles preferably have an average particle size of 0.03 to 1.0 μm. As the polymerizable monomer constituting the resin, styrene; o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-ethylstyrene derivatives; acrylic acid; methacrylic acid; methyl acrylate , Ethyl acrylate, n-butyl acrylate, isobutyl acrylate, n-propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate Acrylic acid esters such as: methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, Lil, phenyl methacrylate, dimethylaminoethyl methacrylate, such as methacrylic acid esters of diethylaminoethyl methacrylate; acrylonitrile, methacrylonitrile, and the like monomers acrylamide.

  Examples of the polymerization method include suspension polymerization, emulsion polymerization, and soap-free polymerization. More preferably, particles obtained by soap-free polymerization are good.

  Other fine particles include lubricants such as polyethylene fluoride, zinc stearate and polyvinylidene fluoride (in particular, polyvinylidene fluoride is preferred); abrasives such as cerium oxide, silicon carbide and strontium titanate (especially strontium titanate) Fluidity-imparting agents such as titanium oxide and aluminum oxide (especially hydrophobic ones are preferred); anti-caking agents; and conductivity-imparting agents such as carbon black, zinc oxide, antimony oxide and tin oxide. . Further, a small amount of white fine particles and black fine particles having a polarity opposite to that of the toner may be used as a developability improver.

  The resin fine particles, inorganic fine powder or hydrophobic inorganic fine powder mixed with the toner is preferably used in an amount of 0.01 to 5 parts by mass (preferably 0.01 to 3 parts by mass) with respect to 100 parts by mass of the toner.

  The toner of the present invention preferably exhibits a sufficient effect when the weight average particle diameter is 2.5 to 10.0 μm, preferably 5.0 to 9.0 μm, more preferably 6.0 to 8.0 μm. And preferred.

  The weight average particle diameter and particle size distribution of the toner are determined using a Coulter counter method. For example, a Coulter Multisizer (manufactured by Coulter Inc.) can be used. As the electrolytic solution, a 1% NaCl aqueous solution is prepared using primary sodium chloride. For example, ISOTON R-II (manufactured by Coulter Scientific Japan) can be used. As a measurement method, 0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 100 to 150 ml of the electrolytic aqueous solution, and 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the volume and number of toner particles of 2.00 μm or more are measured using the 100 μm aperture as the aperture by the measuring device. Volume distribution and number distribution are calculated. Then, the weight-based weight average particle diameter (D4) obtained from the volume distribution according to the present invention is calculated. As channels, 2.00 to less than 2.52 μm; 2.52 to less than 3.17 μm; 3.17 to less than 4.00 μm; 4.00 to less than 5.04 μm; 5.04 to less than 6.35 μm; 6 Less than 35 to 8.00 μm; less than 8.00 to less than 10.08 μm; less than 10.08 to less than 12.70 μm; less than 12.70 to less than 16.00 μm; less than 16.00 to less than 20.20 μm; Use 13 channels less than 40 μm; 25.40 to less than 32.00 μm; 32.00 to less than 40.30 μm.

  The toner of the present invention can be used as a two-component developer in combination with a carrier. As the carrier for use in the two-component development method, a conventionally known carrier can be used. Specifically, particles having an average particle diameter of 20 to 300 μm formed of surface oxidized or unoxidized metal such as iron, nickel, cobalt, manganese, chromium, rare earth, and alloys or oxides thereof are used as carrier particles. The

  The surface of the carrier particles is preferably coated with a substance such as styrene resin, acrylic resin, silicone resin, fluorine resin, or polyester resin.

  The toner particles according to the present invention are obtained by melt-kneading (kneading step) a composition containing a binder resin, a colorant, and other components as necessary, and pulverizing (pulverizing step) the obtained kneaded product. Is obtained. The constituent material of the toner particles is preferably mixed in advance by a ball mill or other mixer and then kneaded using a thermal kneader. Further, the pulverization process may be divided into a coarse pulverization process and a fine pulverization process, and classification (classification process) may be performed thereafter. Furthermore, in order to satisfy the average circularity and average surface roughness of the toner particles according to the present invention, it is preferable to modify the toner particle surface using the surface modifying apparatus as described above, and in particular, after the classification step. It is preferable to perform surface modification. Moreover, it is preferable to perform fine powder removal simultaneously with surface modification.

  When the toner is produced through the kneading step as in the present invention, the constituent material of the toner particles can be uniformly and finely dispersed in the particles. Further, by pulverizing the kneaded material in which the constituent materials are well dispersed, the distribution of the constituent materials on the surface of the toner particles becomes suitable. As a result, the specific average surface roughness and average circularity, which are the characteristics of the present invention, are achieved. The effect of the toner particles having a sufficient degree can be exhibited sufficiently.

  For example, as a mixer, Henschel mixer (Mitsui Mining Co., Ltd.); Super mixer (Kawata Co., Ltd.); Ribocorn (Okawara Seisakusho Co., Ltd.); (Manufactured by Taiheiyo Kiko Co., Ltd.); Ladige mixer (manufactured by Matsubo Co., Ltd.), and kneading machines such as KRC kneader (manufactured by Kurimoto Iron Works); (Manufactured by Toshiba Machine Co., Ltd.); TEX twin-screw kneader (manufactured by Nippon Steel Works); PCM kneader (manufactured by Ikegai Iron Works Co., Ltd.); Mining company); MS pressure kneader, Nider Ruder (Moriyama Seisakusho); Banbury mixer (Kobe Steel) It is below. As a pulverizer, a counter jet mill, a micron jet, an inomizer (manufactured by Hosokawa Micron); an IDS type mill, a PJM jet pulverizer (manufactured by Nippon Pneumatic Industry Co., Ltd.); a cross jet mill (manufactured by Kurimoto Iron Works Co., Ltd.); SK Jet Oh Mill (manufactured by Seishin Enterprise Co., Ltd.); Kryptron (manufactured by Kawasaki Heavy Industries, Ltd.); Turbo Mill (manufactured by Turbo Industry Co., Ltd.); Super Rotor (manufactured by Nissin Engineering Co., Ltd.). Classifiers include: Classy, Micron Classifier, Spedick Classifier (manufactured by Seishin Enterprise); Turbo Classifier (manufactured by Nisshin Engineering); Micron Separator, Turbo Flex (ATP), TSP Separator (manufactured by Hosokawa Micron) Elbow Jet (manufactured by Nippon Steel Mining Co., Ltd.), Dispersion Separator (manufactured by Nippon Pneumatic Industrial Co., Ltd.); YM Microcut (manufactured by Yaskawa Shoji Co., Ltd.). Ultrasonic (Made by Sakae Sangyo Co., Ltd.); Resona sieve, Gyroshifter (Deoksugaku Kojo Co., Ltd.); Vibrasonic system (Made by Dalton); Soniclean (Shinto) (Industry company); Turbo screener (Turbo industry company); Micro shifter (Ogino industry company); Circular vibration sieve, etc.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.

<Production Example L-1 for Low Molecular Weight Component>
Into a four-necked flask, 300 parts by mass of xylene was added, and the inside of the flask was sufficiently replaced with nitrogen while stirring, and then heated to reflux. Under this reflux, 68.8 parts by mass of styrene, acrylic acid n- A mixture of 22 parts by weight of butyl, 9.2 parts by weight of monobutyl maleate and 1.8 parts by weight of di-t-butyl peroxide was added dropwise over 4 hours, and the mixture was held for 2 hours to complete the polymerization. Solvent was used to obtain a low molecular weight polymer (L-1). When GPC and acid value measurement of this polymer were performed, the peak molecular weight was 15000 and the acid value was 30 mgKOH / g. The values are shown in Table 1.

<Production Examples L-2 to L-5 of Low Molecular Weight Components>
Low molecular weight polymer L-2 was prepared in the same manner as in Low molecular weight component production example L-1, except that the amounts of styrene, n-butyl acrylate and monobutyl maleate and the amount of polymerization initiator were changed as shown in Table 1. To L-5. Table 1 shows the peak molecular weight and acid value of the low molecular weight polymers L-2 to L-5.

<Production Example H-1 of High Molecular Weight Component>
Into a four-necked flask, 180 parts by mass of degassed water and 20 parts by mass of a 2% by weight aqueous solution of polyvinyl alcohol were added, then 75.3 parts by mass of styrene, 20 parts by mass of n-butyl acrylate, and 4.7% of monobutyl maleate. Parts by weight, 0.65 parts by weight of di-t-butyl peroxide, 0.008 parts by weight of divinylbenzene, and 0.15 parts by weight of 2,2-bis (4,4-di-t-butylperoxycyclohexyl) propane Was added and stirred to give a suspension. After sufficiently replacing the inside of the flask with nitrogen, the temperature was raised to 90 ° C. to initiate polymerization. The polymerization was completed by maintaining at the same temperature for 24 hours to obtain a high molecular weight polymer (H-1). Thereafter, the polymer (H-1) was filtered off, washed with water, dried, and then subjected to GPC and acid value measurement. As a result, the peak molecular weight was 2.3 million, and the acid value was 8.7.

<Production Examples H-2 to H-4 of High Molecular Weight Components>
In high molecular weight component production example H-1, styrene, n-butyl acrylate, monobutyl maleate, di-t-butyl peroxide, divinylbenzene, 2,2-bis (4,4-di-t-butylperoxycyclohexyl) ) High molecular weight polymers H-2 to H-4 were obtained by the same method except that the amount of propane was changed as shown in Table 1 and divinylbenzene was added as appropriate. Table 1 shows the peak molecular weight and acid value of the high molecular weight polymers H-2 to H-4.

<Binder resin production example 1>
A low molecular weight component L-1 and a high molecular weight component H-1 were mixed in a xylene solution at a mass ratio shown in Table 2 to obtain a binder resin 1. Table 2 shows the physical properties of the obtained binder resin.

<Binder resin production examples 2 to 8>
Binder resins 2 to 8 were obtained in the same manner as in Binder resin production example 1 except that the type of polymer to be mixed was changed as shown in Table 2 in Binder resin production example 1.

<Example 1>
[Preparation of Toner 1]
Binder resin 1 100 parts by mass. Magnetic properties in a magnetic field of spherical magnetic iron oxide (average particle size: 0.21 μm, 79.6 kA / m (1 k Oersted) [σr: 5.1 Am ² / kg, σs: 69. 6Am ² / kg])
95 parts by mass / negative charge control agent (iron azo compound, manufactured by Hodogaya Chemical Co., Ltd .: T-77) 2 parts by mass / wax (Fischer-Tropsch, melting point = 104 ° C., Mn = 780,
Mw = 1060) 4 parts by mass The above mixture was premixed with a Henschel mixer, melt kneaded with a biaxial extruder heated to 110 ° C., and the cooled kneaded product was coarsely pulverized with a hammer mill to obtain a coarsely pulverized toner product It was. The obtained coarsely pulverized product was coated with a mechanical pulverizer turbo mill (manufactured by Turbo Kogyo Co., Ltd .; coated with chromium alloy plating containing chromium carbide on the rotor and stator surfaces (plating thickness 150 μm, surface hardness HV1050)). Then, based on the condition table of Table 3, the air temperature is adjusted and mechanically pulverized to finely pulverize, and the resulting finely pulverized product is a multi-division classifier using the Coanda effect (elbow jet classification manufactured by Nittetsu Mining Co., Ltd.). Machine), fine powder and coarse powder were simultaneously classified and removed. The weight average particle diameter (D ₄ ) measured by the Coulter counter method of the obtained raw toner particles is 6.6 μm, and the cumulative value of the particle size distribution based on the number of toner particles less than 4 μm is 25.3 number%. there were.

The raw toner particles were subjected to surface modification and fine powder removal using a surface modification apparatus shown in FIG. At this time, in this example, 16 square disks were installed on the upper part of the dispersion rotor, the distance between the guide ring and the upper square disk of the dispersion rotor was 60 mm, and the distance between the dispersion rotor and the liner was 4 mm. Further, the rotational peripheral speed of the dispersion rotor was 140 m / sec, and the blower air volume was 30 m ³ / min. The input amount of the finely pulverized product was 300 kg / hr, and the cycle time was 45 sec. The temperature of the refrigerant passed through the jacket was −15 ° C., and the cold air temperature T1 was −20 ° C. Furthermore, the particle ratio of 0.6 μm or more and less than 3 μm was set to a desired value by controlling the rotation speed of the classification rotor. Through the above-described steps, negative chargeability in which the cumulative value of the number-based particle size distribution of toner particles having a weight average particle diameter (D ₄ ) of 6.8 μm and less than 4 μm measured by the Coulter counter method is 18.1% by number. Toner particles 1 were obtained.

  Table 4 shows the values of the methanol concentration of the toner particles 1 measured with the FPIA 2100, the transmittance of light having a wavelength of 780 nm, and the measured value of the scanning probe microscope, and FIG. 3 shows the methanol concentration-transmittance curve.

  The average circularity of the toner 1 measured with the FPIA 2100 and having an equivalent circle diameter of 3 μm or more and 400 μm or less is 0.947, and the average surface roughness of the toner 1 measured with a scanning probe microscope is 16.5 nm. there were.

[Preparation of Toners 2 to 10]
The binder resin to be used is changed as shown in Table 3, the finely pulverizing conditions of the turbo mill are changed as shown in Table 3, the classification conditions in the multi-division classifier are changed, and the conditions of the surface reformer are also shown in Table 3. Toners 2 to 10 were obtained in the same manner as Toner 1 except as described above. Table 4 shows the physical properties of toner particles 2 to 10 measured with FPIA 2100, the value of methanol concentration with respect to the transmittance of light having a wavelength of 780 nm, and the measured values with a scanning probe microscope.

  Among these, the average circularity of the toner 10 having a circle-equivalent diameter of 3 μm or more and 400 μm or less measured with the FPIA 2100 is 0.934, and the average surface roughness of the toner 10 measured with a scanning probe microscope is 30.0 nm. Met.

[Preparation of Toner 11]
The binder resin to be used is changed as shown in Table 3, and the pulverization conditions of the turbo mill are changed as shown in Table 3, the classification conditions in the multi-division classifier are changed, and the resulting toner particles are heated with 300 ° C. hot air. A toner 11 was obtained in the same manner as the toner 1 except that a treatment for instantaneously passing the inside was performed. Table 4 shows the physical properties of the toner particles 11 measured with FPIA 2100, the methanol concentration values with respect to the transmittance of light having a wavelength of 780 nm, and the measured values with a scanning probe microscope.

[Preparation of Toner 12]
The binder resin to be used is changed as shown in Table 3, and the finely pulverized conditions of the turbo mill are changed as shown in Table 3, the classification conditions in the multi-division classifier are changed, and the surface modification by the surface reformer is further performed. Toner 12 was obtained in the same manner as Toner 1 except that this was not performed. Table 4 shows the physical properties of the toner particles 12 measured with FPIA 2100, the methanol concentration values with respect to the transmittance of light having a wavelength of 780 nm, and the measured values with a scanning probe microscope.

[Preparation of Toner 13]
The binder resin to be used is as shown in Table 3, using a jet airflow type pulverizer without using a mechanical pulverizer, and further changing the classification conditions in the multi-division classifier. A toner 13 was obtained in the same manner as the toner 1 except that a treatment for instantaneously passing through hot air was performed. Table 4 shows the physical properties of the toner particles 13 measured with FPIA 2100, the methanol concentration values with respect to the transmittance of light having a wavelength of 780 nm, and the measured values with a scanning probe microscope.

[Preparation of Toner 14]
The binder resin to be used is as shown in Table 3, using a jet airflow pulverizer instead of a mechanical pulverizer, changing the classification conditions in the multi-division classifier, and further modifying the surface with a surface reformer. Toner 14 was obtained in the same manner as Toner 1 except that this was not performed. Table 4 shows the physical properties of the toner particles 14 measured with FPIA 2100, the methanol concentration values with respect to the transmittance of light having a wavelength of 780 nm, and the measured values with a scanning probe microscope.

<Examples 1-9, Comparative Examples 1-5>
Next, the prepared toner was used for evaluation by the following method. The evaluation results are shown in Table 5.

  The following evaluation was performed using a laser beam printer Laser Jet 4300n manufactured by Hewlett-Packard.

(1) Toner consumption Image printing test of 18000 sheets on plain paper for copying machines (A4 size: 75 g / m ² ) with an image with a printing ratio of 4% in a normal temperature and humidity environment (23 ° C., 60% RH). Before and after the process, the amount of toner in the toner container was measured, and the amount of toner consumed per image was measured.

(2) Fixing test Regarding the low-temperature fixability, the fixing unit of the evaluation apparatus was taken out and modified so that it could be evaluated at a process speed 1.1 times that of a normal one. In the heat fixing device, the temperature of the heater is controlled every 5 ° C. in the temperature range of 150 to 240 ° C., and after the surface temperature of the fixing roller becomes constant, the recording material on which the unfixed toner image is formed is fixed to the fixing nip. The resulting image is rubbed 5 times with sylbon paper applied with a load of 4.9 kPa, and the fixing temperature at which the density reduction rate of the image density before and after rubbing is 10% or less is fixed at a low temperature. It was sex. The lower this temperature, the better the low-temperature fixability. As the unfixed image, plain paper (75 g / m ² ) was used, and a solid black image was fixed with the toner development amount on the paper set to 0.6 mg / cm ² .

The high temperature offset resistance was evaluated by inserting the recording material in a state where the surface of the fixing roller was sufficiently heated, similar to the above fixing conditions. A horizontal line pattern (width 100 μm, interval 100 μm) in the upper half and a solid black and white image in the lower half were printed, showing the highest temperature at which no smudge occurred on the white image. As test paper, plain paper for copying machines (60 g / m ² ), which is likely to cause offset, was used. In the evaluation, the stain on the image due to the high temperature offset phenomenon was visually confirmed, and the generated temperature was regarded as the high temperature offset resistance. The higher this temperature, the better the high temperature offset property.

(3) Transfer efficiency Using normal paper for copying machines (A4 size: 75 g / m ² ) in a normal temperature and normal humidity environment (23 ° C., 60% RH), the transfer was performed at an interval of 100 sheets from the initial to 500 sheets. The measurement method is to stop the main body while outputting a solid black image, and measure the amount of toner per unit area developed on the photosensitive drum and the amount of toner per unit area transferred onto the transfer material. To do. Then, the amount of toner on the transfer material was obtained by dividing by the amount of toner on the photosensitive drum. The results were averaged every 100 sheets.

(4) Blotch In the durability under a low temperature and low humidity environment, the blotch was evaluated from the toner coat state on the developing sleeve during printing and the printed image.
A No blotch is seen on the developing sleeve.
B Although slightly seen on the developing sleeve, the effect does not appear on the image.
C It is seen on the developing sleeve and the effect appears faintly on the image.
D Blotches are seen on the developing sleeve, and the effect appears remarkably on the image.

(5) Sleeve negative ghost Print out 18,000 sheets of ordinary copier plain paper (A4 size: 75 g / m ² ) in a low-temperature, low-humidity environment (15 ° C, 10% RH), and sleeve negative ghost every 4500 sheets. Was evaluated. For the image evaluation related to ghost, a solid black band was output only for one round of the sleeve, and then a halftone image was output. A schematic diagram of the pattern is shown in FIG. The evaluation method is a Macbeth densitometer at the place where the black image is formed on the second round of the sleeve (black print portion) and the place where the black image is not formed (non-image portion) in one print image. The difference in reflection density measured by was calculated as follows. In the negative ghost image, the image density of the black printed portion in the first round of the sleeve is generally lower than the image density of the non-image portion in the first round of the sleeve. This is a ghost phenomenon where the shape of the pattern produced in the first round appears as it is. The density difference here was evaluated by measuring the reflection density difference.
Reflection density difference = reflection density (place where no image is formed) −reflection density (place where an image is formed)

The smaller the reflection density difference is, the better the level is without ghosting. As a comprehensive evaluation of ghosts, the evaluation is made in four stages of A, B, C, and D, and the worst evaluation result among the evaluations for every 4500 sheets is shown in Table 6.
Reflection density difference 0.00 or more and less than 0.02: A
0.02 or more and less than 0.04: B
0.04 or more and less than 0.06: C
0.06 or more: D

(6) Scattering In durability under normal temperature and normal humidity environment, a lattice pattern (interval of 1 cm) at 100 μm (latent image) line was printed at the initial time and 18,000 sheets, and the scattering was visually evaluated using an optical microscope.
A: The line is very sharp and hardly splattered. B: The line is comparatively sharp with a slight splattering. C: Slightly splattering makes the line feel dull. D: Less than C level

(7) Image density, fog Under a low temperature and low humidity environment (15 ° C., 10% RH) and a high temperature and high humidity environment (32.5 ° C., 80% RH), a printing speed of 2 sheets / 10 seconds, An image print test of 9000 sheets was performed on plain paper for copying machines (A4 size: 75 g / m ² ) at a printing ratio of 3%, and the image print test was performed for a total of 18,000 sheets after leaving it for a day. . The results are shown in Table 5.

  For the image density, a “Macbeth reflection densitometer” (manufactured by Macbeth) was used to measure a relative density with respect to a printout image of a white background portion having an original density of 0.00.

  The fog was calculated from a comparison between the whiteness of the transfer paper measured with a reflectometer (manufactured by Tokyo Denshoku Co., Ltd.) and the whiteness of the transfer paper after printing solid white.

It is a schematic sectional drawing of the surface modification apparatus of an example used in the surface modification process of this invention. It is the schematic which shows an example of the top view of the dispersion | distribution rotor shown in FIG. 3 is a graph showing the transmittance of toner particles 1 of Example 1 of the present invention with respect to methanol concentration. It is explanatory drawing of the pattern for evaluating a sleeve ghost.

Explanation of symbols

31 Classification rotor 32 Fine powder recovery 33 Raw material supply port 34 Liner 35 Cold air introduction port 36 Dispersion rotor 37 Product discharge port 38 Discharge valve 39 Guide ring 40 Square disk 41 First space 42 Second space

Claims (7)

In a toner composed of toner particles and inorganic fine particles containing at least a binder resin and a colorant,
The toner particles having an equivalent circle diameter of 3 μm or more and 400 μm or less measured by the flow type particle image measuring apparatus of the toner particles have an average circularity of 0.935 or more and less than 0.970, and the toner particles are measured by a scanning probe microscope. The average surface roughness is 5.0 nm or more and less than 35.0 nm,
Further, in the chromatogram obtained by gel permeation chromatography of the tetrahydrofuran-soluble matter in the toner, it has a main peak in a region having a molecular weight of 3.0 × 10 ³ or more and less than 3.0 × 10 ⁴ and a molecular weight of 5.0 ×. A toner having at least one sub-peak or shoulder in an area of 10 ⁴ or more and less than 1.0 × 10 ⁸ .   In the number-based particle size distribution of toner particles having an equivalent circle diameter of 0.6 μm or more and 400 μm or less measured by the flow type particle image measuring apparatus of the toner particles, the ratio of toner particles of 0.6 μm or more and less than 3 μm is 0% by number or more. The toner according to claim 1, wherein the toner is less than 20% by number.   The wettability of the toner particles with respect to the methanol / water mixed solvent is characterized in that the methanol concentration when the light transmittance at a wavelength of 780 nm is 80% and the methanol concentration when the transmittance is 50% is 35 to 75% by volume. The toner according to claim 1 or 2.   4. The toner according to claim 1, wherein the toner particles have a cumulative number of toner particles having a circularity of less than 0.960 of 20% or more and less than 70%.   The toner according to claim 1, wherein a maximum height difference of the toner particles measured by a scanning probe microscope is 50 nm or more and less than 250 nm. Measured with a scanning probe microscope of the toner particles, to claim 1 surface area when the 1μm square area of the surface was measured for the toner particles and less than 1.03 .mu.m ² or more 1.33 ² The toner according to any one of 5. The average circularity of the toner having an equivalent circle diameter of 3 μm or more and 400 μm or less measured by the flow type particle image measuring apparatus of the toner is 0.935 or more and less than 0.970, and the average of the toner measured by a scanning probe microscope the toner according to any one of claims 1 to 6 surface roughness and less than or 10.0 nm 26.0 nm.

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