JP2019008306A - Method for producing resin particles - Google Patents

Abstract

To provide a method for producing resin particles which simplifies the process of manufacturing resin particles and has good narrow particle size distribution, replenishment property and heat resistant storage stability.SOLUTION: The method for producing resin particles includes a droplet discharging step of discharging a resin particle composition liquid from a discharge hole to form a droplet and a solidification step of solidifying the droplet; the composition liquid of the resin particles contains at least a binder resin, a release agent and fine particles, in which the contact angle of the binder resin with respect to water is 90° or less, and the degree of hydrophobicity is 65% or more.SELECTED DRAWING: None

Description

  The present invention relates to a method for producing resin particles. Specific examples of the resin particles include toner used for developing an electrostatic charge image in electrophotography, electrostatic recording, electrostatic printing, and the like.

  In recent years, there has been a demand in the market to reduce the toner particle size in order to improve the quality of output images. Further, from the viewpoint of reducing the environmental load, a toner manufacturing process that saves resources and energy is required.

Conventionally, as dry toners used for electrophotography, electrostatic recording, electrostatic printing, etc., so-called pulverized toners, in which a toner binder such as a styrene resin or a polyester resin is melt-kneaded together with a colorant and pulverized, are widely used. It is used.
However, in recent years, there has been a tendency for the toner to have a small particle size in order to obtain a high-quality image. In the above pulverization method, if the particle size is 6 μm or less, the pulverization efficiency decreases and the loss due to classification increases, resulting in increased productivity. This is a problem in that the cost is low.

In addition, a so-called polymerization type toner such as a suspension polymerization method and an emulsion polymerization aggregation method, and a method involving volume shrinkage called a polymer dissolution suspension method have been proposed and put into practical use (see Patent Document 1). These toners are excellent in terms of producing a toner having a small particle diameter.
However, since it is assumed that the dispersant is used in an aqueous medium, the dispersant that impairs the charging characteristics of the toner remains on the surface of the toner, causing problems such as loss of environmental stability and removal of this. It is known that a very large amount of washing water is required to achieve this, and this is a problem in that it is not always satisfactory as a production method.

As an alternative method for producing toner, a method has been proposed in which fine droplets are formed from fine nozzles using piezoelectric pulses, and then dried and solidified to form toner (see Patent Document 2). In addition, a method has been proposed in which fine droplets are formed by utilizing thermal expansion in the nozzle, and this is dried and solidified into a toner (see Patent Document 3). Furthermore, a method has been proposed in which minute droplets are formed using an acoustic lens and dried to solidify into toner (see Patent Document 4).
However, with these methods, it is easy to reduce the particle size of the toner, but there is a problem in that the number of droplets that can be ejected from one nozzle per unit time is small and productivity is low. This is a problem in that the spread of the particle size distribution due to coalescence cannot be avoided and a toner having a uniform particle diameter cannot be obtained, and there is a case where loss due to classification may occur.

  Furthermore, in the current toner production, there is an external addition process in which inorganic fine particles are added by mixing after the toner base is produced. If there is a problem in the externally added state, the toner replenishment property and the heat-resistant storage property are deteriorated, which is one of the very important steps in producing the toner. However, in order to improve production efficiency and reduce manufacturing costs, it is desirable that the number of steps is as short as possible. In the past, a technique for fixing or burying fine particles on a toner base in the gas phase has been proposed, but the equipment becomes complicated because it is necessary to spray the externally added fine particles and the toner base fine particles from separate nozzles. Also, the equipment is expensive. (See Patent Documents 5 and 6)

Further, a toner composition liquid containing a resin, a colorant, and inorganic fine particles having a hydrophobicity of 15 to 55% is formed into droplets from a columnar shape through a constricted state, and the droplets are changed into solid particles in the granulation space. Thus, a method for producing toner has been proposed (see Patent Document 7).
However, this method has not been sufficiently effective in adding inorganic fine particles.
Therefore, the present situation is that there is a need to provide a toner and a toner production method that simplify the toner production process and that have good narrow particle size distribution, replenishability, and heat resistant storage stability.

  An object of the present invention is to solve the above-described problems and achieve the following objects. That is, an object of the present invention is to provide a method for producing resin particles that simplifies the production process of resin particles and has good narrow particle size distribution, replenishment properties, and heat-resistant storage stability.

The feature of the present invention, which is a means for solving the above problems, is as follows (1).
(1) A resin particle manufacturing method comprising: a droplet discharge step of discharging a resin particle composition liquid from a discharge hole to form droplets; and a solidification step of solidifying the droplets, wherein the resin particle composition liquid Contains at least a binder resin, a release agent and fine particles, the contact angle of the binder resin with respect to water is 90 ° or less, and the degree of hydrophobicity of the fine particles with respect to methanol is 65% or more. The manufacturing method of the resin particle characterized by the above-mentioned.

  In the present invention, it is possible to provide a method for producing resin particles that simplifies the production process of resin particles and has good narrow particle size distribution, replenishability, and heat-resistant storage stability.

It is sectional drawing which shows the structure of a liquid column resonance droplet formation means. It is sectional drawing which shows the structure of a liquid column resonance droplet unit. It is sectional drawing of a discharge hole. It is the schematic which shows the standing wave of the speed and pressure fluctuation in the case of N = 1,2,3. It is the schematic which shows the standing wave of the speed and pressure fluctuation in the case of N = 4 and 5. It is the schematic which shows the mode of the liquid column resonance phenomenon which arises in the liquid column resonance flow path of a liquid column resonance droplet formation means. It is a figure which shows the mode of droplet discharge. It is a characteristic view which shows a drive frequency and a droplet discharge speed frequency characteristic. It is the schematic of a particle manufacturing apparatus. It is sectional drawing which shows the structure of a liquid column resonance droplet formation means. FIG. 3 is a TEM photograph of a cross section of the toner of the present invention.

The best mode for carrying out the present invention will be described below with reference to the drawings.
The method for producing resin particles of the present invention is a method for producing resin particles in a gaseous medium. An example of the means for producing resin particles of the present invention will be described below with reference to FIGS. In the present invention, spray granulation is used as the resin particle production means. However, the principle in the present specification is applied as long as it is a means for producing resin particles in a gaseous medium, and the production method is not limited to this production method. The spray granulation means is divided into a droplet discharge means and a droplet solidification collecting means. Each is explained below.
The present invention relates to a method for producing resin particles. Hereinafter, the present invention will be described using toner as an example of resin particles. Therefore, hereinafter, the resin particles are referred to as toner, and the resin particle composition liquid is referred to as toner composition liquid.

[Droplet discharge means]
The droplet discharge means used in the present invention is not particularly limited as long as the particle size distribution of the discharged droplets is narrow, and a known one can be used. Examples of the droplet discharge means include a one-fluid nozzle, a two-fluid nozzle, a membrane vibration type discharge means, a Rayleigh split type discharge means, a liquid vibration type discharge means, and a liquid column resonance type discharge means. A film vibration type droplet discharge means is described in, for example, Japanese Patent Application Laid-Open No. 2008-292976. A Rayleigh splitting type droplet discharge means is described in, for example, Japanese Patent No. 4647506. A liquid vibration type droplet discharge means is described in, for example, Japanese Patent Application Laid-Open No. 2010-102195.
In order to narrow the particle size distribution of the droplets and ensure the productivity of the toner, for example, liquid droplet resonance can be used. In droplet liquid column resonance, the liquid in the liquid column resonance liquid chamber is vibrated to form a standing wave by liquid column resonance, and from a plurality of discharge holes formed in the antinode of the standing wave. What is necessary is just to discharge a liquid.

[Liquid column resonance ejection means]
The liquid droplet ejection means will be described by taking as an example a liquid column resonance type ejection means for ejecting using liquid column resonance.
FIG. 1 shows a liquid column resonance droplet discharge means 11. The liquid column resonance droplet discharge means 11 includes a liquid common supply path 17 and a liquid column resonance liquid chamber 18. The liquid column resonance liquid chamber 18 communicates with a liquid common supply path 17 provided on one of the wall surfaces at both ends in the longitudinal direction. Further, the liquid column resonance liquid chamber 18 is provided on a wall surface facing the discharge hole 19 and a discharge hole 19 for discharging the droplet 21 to one wall surface of the wall surfaces connected to both ends. Vibration generating means 20 for generating high-frequency vibrations to form standing waves. The vibration generating means 20 is connected to a high frequency power source (not shown). Reference numeral 12 denotes an airflow passage.

  In the present invention, a liquid containing a component that forms toner particles is referred to as a “toner composition liquid”. The toner composition liquid is discharged from the discharge means, and may be a liquid under the discharge conditions. The toner composition liquid may be in a state where the components of the toner particles to be obtained are dissolved or dispersed, or in a state where the toner particle components are melted without containing a solvent.

  The toner composition liquid 14 passes through a liquid supply pipe by a liquid circulation pump (not shown) and flows into the liquid common supply path 17 of the liquid column resonance droplet forming unit 10 shown in FIG. 2, and the liquid column resonance droplet shown in FIG. It is supplied to the liquid column resonance liquid chamber 18 of the discharge means 11. A pressure distribution is formed in the liquid column resonance liquid chamber 18 filled with the toner composition liquid 14 by the liquid column resonance standing wave generated by the vibration generating means 20. Then, the droplet 21 is ejected from the ejection hole 19 arranged in a region where the amplitude of the liquid column resonance standing wave is large and the pressure fluctuation is large and which is an antinode of the standing wave. The region that becomes the antinode of the standing wave due to the liquid column resonance means a region other than the node of the standing wave. Preferably, it is a region where the pressure fluctuation of the standing wave has an amplitude large enough to discharge the liquid, and more preferably a position where the amplitude of the pressure standing wave becomes a maximum (a section as a velocity standing wave). ) To a minimum position in a range of ± 1/4 wavelength.

  If the region is an antinode of a standing wave, even if there are a plurality of discharge holes, substantially uniform droplets can be formed from each, and moreover, the droplets can be discharged efficiently. And clogging of the discharge holes is less likely to occur. The toner composition liquid 14 that has passed through the liquid common supply path 17 flows through a liquid return pipe (not shown) and is returned to the raw material container. When the amount of the toner composition liquid 14 in the liquid column resonance liquid chamber 18 decreases due to the discharge of the liquid droplets 21, a suction force due to the action of the liquid column resonance standing wave in the liquid column resonance liquid chamber 18 acts, and the liquid common supply The flow rate of the toner composition liquid 14 supplied from the path 17 increases. Then, the toner composition liquid 14 is replenished in the liquid column resonance liquid chamber 18. When the toner composition liquid 14 is replenished in the liquid column resonance liquid chamber 18, the flow rate of the toner composition liquid 14 passing through the liquid common supply path 17 is restored.

  Each of the liquid column resonance liquid chambers 18 in the liquid column resonance droplet discharge means 11 has a frame formed of a material having such a high rigidity that does not affect the resonance frequency of the liquid at a driving frequency such as metal, ceramics, or silicon. It is formed by bonding. Further, as shown in FIG. 1, the length L between the wall surfaces at both ends in the longitudinal direction of the liquid column resonance liquid chamber 18 is determined based on the liquid column resonance principle as described later. Further, the width W of the liquid column resonance liquid chamber 18 shown in FIG. 2 is desirably smaller than one half of the length L of the liquid column resonance liquid chamber 18 so as not to give an extra frequency to the liquid column resonance. . Furthermore, it is preferable that a plurality of liquid column resonance liquid chambers 18 are arranged for one droplet forming unit 10 in order to dramatically improve productivity. The range is not limited, but one droplet forming unit provided with 100 to 2000 liquid column resonance liquid chambers 18 is most preferable because both operability and productivity can be achieved. In addition, for each liquid column resonance liquid chamber, a flow path for supplying liquid is connected from the common liquid supply path 17, and the common liquid supply path 17 communicates with a plurality of liquid column resonance liquid chambers 18. .

Further, the vibration generating means 20 in the liquid column resonance droplet discharging means 11 is not particularly limited as long as it can be driven at a predetermined frequency, but a form in which a piezoelectric body is bonded to the elastic plate 9 is desirable. The elastic plate constitutes a part of the wall of the liquid column resonance liquid chamber so that the piezoelectric body does not come into contact with the liquid. Examples of the piezoelectric body include piezoelectric ceramics such as lead zirconate titanate (PZT). However, since the amount of displacement is generally small, the piezoelectric body is often used by being laminated. In addition, piezoelectric polymers such as polyvinylidene fluoride (PVDF), single crystals such as quartz, LiNbO ₃ , LiTaO ₃ , KNbO _{3, and the} like can be given. Furthermore, it is desirable that the vibration generating means 20 is arranged so that it can be individually controlled for each liquid column resonance liquid chamber. In addition, the block-shaped vibrating member made of one material is partially cut in accordance with the arrangement of the liquid column resonance liquid chambers, and each liquid column resonance liquid chamber can be individually controlled via an elastic plate. desirable.

  Furthermore, the diameter of the opening of the discharge hole 19 is desirably in the range of 1 [μm] to 40 [μm]. By being 1 [μm] or more, it is possible to prevent the droplets from becoming too small and to form droplets of an appropriate size. Even in the case where the toner contains a solid fine particle such as a pigment as a constituent component of the toner, the discharge hole 19 is not clogged, and the productivity can be improved. Moreover, it can prevent that the diameter of a droplet becomes large too much because it is 40 [micrometers] or less. As a result, the toner composition liquid can be dried and solidified without significantly diluting to obtain a desired toner particle diameter of 3 to 6 μm. It may be necessary to dilute the toner composition to a very dilute solution with an organic solvent, which can reduce the amount of organic solvent used for dilution and reduce the drying energy required to obtain a certain amount of toner. Can do. Further, as can be seen from FIG. 2, adopting a configuration in which the discharge holes 19 are provided in the width direction in the liquid column resonance liquid chamber 18 can provide a large number of openings of the discharge holes 19, thereby increasing the production efficiency. Therefore, it is preferable. Further, since the liquid column resonance frequency varies depending on the arrangement of the discharge holes 19, it is desirable to appropriately determine the liquid column resonance frequency after confirming the discharge of the droplet.

The sectional shape of the discharge hole 19 is described as a tapered shape in which the diameter of the opening is reduced in FIG. 1 and the like, but the sectional shape can be appropriately selected.
FIG. 3 shows a cross-sectional shape that the discharge hole 19 can take.
(A) has a shape in which the opening diameter becomes narrow while having a round shape from the liquid contact surface of the discharge hole 19 toward the discharge hole, and near the outlet of the discharge hole 19 when the thin film 41 vibrates. Since the pressure applied to the liquid is maximized, it is the most preferable shape for stabilizing the discharge.

(B) has a shape in which the opening diameter becomes narrow with a certain nozzle angle 24 from the liquid contact surface of the discharge hole 19 toward the discharge hole, and this nozzle angle 24 can be changed as appropriate. . The pressure applied to the liquid can be increased in the vicinity of the outlet of the discharge hole 19 when the thin film 41 vibrates by the nozzle angle 24 similar to (a), but the range is preferably 60 ° to 90 °. By setting the angle to 60 ° or more, a sufficient pressure can be applied to the liquid, and the thin film 41 can be easily processed. When the nozzle angle 24 is 90 °, (c) corresponds. However, by setting the maximum value to 90 °, it is not difficult to apply pressure to the outlet, so that droplet discharge is stabilized.
(D) is a shape combining (a) and (b). In this way, the shape may be changed step by step.

Next, the mechanism of droplet formation by the droplet formation unit in liquid column resonance will be described.
First, the principle of the liquid column resonance phenomenon occurring in the liquid column resonance liquid chamber 18 in the liquid column resonance droplet discharge means 11 of FIG. 1 will be described. The sound velocity of the toner composition liquid in the liquid column resonance liquid chamber is c, and vibration is generated. When the drive frequency given from the means 20 to the toner composition liquid as a medium is f, the wavelength λ at which the liquid resonance occurs is
λ = c / f (Formula 1)
Are in a relationship.

In the liquid column resonance liquid chamber 18 of FIG. 1, the length from the end of the frame on the fixed end side to the end on the liquid common supply path 17 side is L. The height h1 (= about 80 [μm]) of the end of the frame on the liquid common supply path 17 side is about twice the height h2 (= about 40 [μm]) of the communication port, and the end is closed. It is equivalent to the fixed end. In the case of such fixed ends on both sides, resonance is formed most efficiently when the length L matches an even multiple of one-fourth of the wavelength λ. That is, it is expressed by the following formula 2.
L = (N / 4) λ (Expression 2)
(However, N is an even number.)

Furthermore, the above formula 2 is also established in the case of a double-sided open end where both ends are completely open.
Similarly, when one side is equivalent to an open end having a pressure relief portion and the other side is closed (fixed end), that is, one side fixed end or one side open end, the length L is the wavelength λ. Resonance is most efficiently formed when it matches an odd multiple of a quarter. That is, N in Expression 2 is expressed as an odd number.

The most efficient drive frequency f is obtained from the above formula 1 and the above formula 2.
f = N × c / (4L) (Formula 3)
It is guided. However, in reality, since the liquid has a viscosity that attenuates the resonance, the vibration is not amplified infinitely, and has a Q value. As shown in equations 4 and 5, which will be described later, Resonance also occurs at frequencies near the highly efficient drive frequency f.

  FIG. 4 shows the shape of the standing wave of velocity and pressure fluctuation (resonance mode) when N = 1, 2, and 3. FIG. 5 shows the standing wave of velocity and pressure fluctuation when N = 4, 5. The shape (resonance mode) is shown. Originally, it is a dense wave (longitudinal wave), but it is generally expressed as shown in FIGS. The solid line is the velocity standing wave, and the dotted line is the pressure standing wave. For example, as can be seen from FIG. 3A showing the case of a fixed end with N = 1, in the case of velocity distribution, the amplitude of the velocity distribution is zero at the closed end, and the amplitude is maximum at the open end. Easy to understand. When the length between both ends in the longitudinal direction of the liquid column resonance liquid chamber is L, the wavelength at which the liquid resonates is λ, and the standing wave is most efficiently generated when the integer N is 1 to 5. . In addition, since the standing wave pattern varies depending on the open / closed state of both ends, they are also shown. As will be described later, the condition of the end is determined by the state of the opening of the discharge hole and the opening of the supply side.

  In acoustics, the open end is an end where the moving speed of the medium (liquid) in the longitudinal direction becomes maximum, and conversely, the pressure becomes minimum. The closed end is considered as an acoustically hard wall and wave reflection occurs. When ideally completely closed or open, a resonant standing wave of the form shown in FIGS. 4 and 5 is generated by superposition of waves, but it is also determined by the number of discharge holes and the position of the discharge holes. The standing wave pattern fluctuates, and the resonance frequency appears at a position deviated from the position obtained from the above Equation 3. In this case, stable ejection conditions can be created by appropriately adjusting the drive frequency.

  For example, the sound velocity c of the liquid is 1,200 [m / s], the length L of the liquid column resonance liquid chamber is 1.85 [mm], wall surfaces exist at both ends, and it is completely equivalent to the fixed ends on both sides. When N = 2 resonance mode is used, the most efficient resonance frequency is derived as 324 kHz from the above equation (3). In another example, the sound velocity c of the liquid is 1,200 [m / s], the length L of the liquid column resonance liquid chamber is 1.85 [mm], and there are wall surfaces at both ends using the same conditions as described above. Thus, when N = 4 resonance mode equivalent to the fixed ends on both sides is used, the most efficient resonance frequency is derived as 648 kHz from the above equation 3. Thus, higher-order resonance can be used also in the liquid column resonance liquid chamber having the same configuration.

  The liquid column resonance liquid chamber in the liquid column resonance droplet discharge means 11 shown in FIG. 1 is an end that can be described as an acoustically soft wall due to the influence of the opening of the discharge hole or whether both ends are equivalent to the closed end state. Although it is preferable to increase the frequency, it is not limited to this and may be an open end. The influence of the opening of the discharge hole here means that the acoustic impedance is reduced, and in particular, the compliance component is increased. Therefore, the configuration in which the wall surfaces are formed at both ends in the longitudinal direction of the liquid column resonance liquid chamber as shown in FIG. 4B and FIG. 5A is regarded as the resonance mode at both fixed ends and the discharge hole side as an opening. This is a preferred configuration because all resonance modes at one open end can be used.

  In addition, the numerical aperture of the discharge holes, the opening arrangement position, and the cross-sectional shape of the discharge holes are factors that determine the drive frequency, and the drive frequency can be appropriately determined accordingly. For example, when the number of ejection holes is increased, the restriction at the tip of the liquid column resonance liquid chamber, which has been the fixed end, gradually loosens, a resonance standing wave that is almost close to the open end is generated, and the drive frequency increases. In addition, the opening position of the discharge hole that is closest to the liquid supply path is the starting point, and it becomes a loose constraint condition. The cross-sectional shape of the discharge hole is round, or the volume of the discharge hole varies depending on the thickness of the frame. The upper standing wave has a short wavelength and is higher than the driving frequency. When a voltage is applied to the vibration generating means at the drive frequency determined in this way, the vibration generating means is deformed, and a resonant standing wave is generated most efficiently at the drive frequency. Further, the liquid column resonance standing wave is generated even at a frequency in the vicinity of the drive frequency at which the resonance standing wave is generated most efficiently. That is, the length between both ends in the longitudinal direction of the liquid column resonance liquid chamber is L, and the distance to the discharge hole closest to the end on the liquid supply side is Le. At this time, the vibration generating means is vibrated using a drive waveform mainly composed of the drive frequency f in the range determined by the following formulas 4 and 5 using the lengths of both L and Le, and liquid column resonance is performed. It is possible to induce and discharge a droplet from the discharge hole.

N × c / (4L) ≦ f ≦ N × c / (4Le) (Formula 4)
N × c / (4L) ≦ f ≦ (N + 1) × c / (4Le) (Formula 5)

  The ratio of the length L between both ends in the longitudinal direction of the liquid column resonance liquid chamber to the distance Le to the discharge hole closest to the end on the liquid supply side is preferably Le / L> 0.6.

  A liquid column resonance pressure standing wave is formed in the liquid column resonance liquid chamber 18 of FIG. 1 using the principle of the liquid column resonance phenomenon described above, and the discharge holes 19 arranged in a part of the liquid column resonance liquid chamber 18. In this case, droplet discharge occurs continuously. Note that it is preferable to dispose the discharge hole 19 at a position where the pressure of the standing wave fluctuates the most, since the discharge efficiency is increased and the driving can be performed with a low voltage. Further, one discharge hole 19 may be provided for one liquid column resonance liquid chamber 18, but it is preferable to arrange a plurality of discharge holes 19 from the viewpoint of productivity. Specifically, it is preferably between 2 and 100.

  By setting the number to 100 or less, the voltage applied to the vibration generating means 20 can be kept low when desired droplets are formed from the ejection holes 19, and the behavior of the piezoelectric body as the vibration generating means 20 can be stabilized. Can do. When the plurality of discharge holes 19 are opened, the pitch between the discharge holes is preferably 20 [μm] or more and not more than the length of the liquid column resonance liquid chamber. By setting the pitch between the ejection holes to 20 [μm] or more, it is possible to reduce the probability that droplets discharged from adjacent ejection holes collide with each other to form large droplets, and the toner particle size distribution. Can be improved.

  Next, the state of the liquid column resonance phenomenon occurring in the liquid column resonance liquid chamber in the droplet discharge head in the droplet forming unit will be described with reference to FIG. In the figure, the solid line drawn in the liquid column resonance liquid chamber represents the velocity distribution plotting the velocity at any measurement position from the fixed end side to the liquid common supply path side end in the liquid column resonance liquid chamber. The direction from the common liquid supply path to the liquid column resonance liquid chamber is +, and the opposite direction is −. In addition, the dotted line marked in the liquid column resonance liquid chamber indicates a pressure distribution in which the pressure value at each arbitrary measurement position between the fixed end side and the liquid common supply path side end in the liquid column resonance liquid chamber is plotted. The positive pressure is + with respect to the atmospheric pressure, and the negative pressure is-. Moreover, if it is a positive pressure, a pressure will be applied to the downward direction in the figure, and if it is a negative pressure, a pressure will be applied to the upward direction in the figure. Further, in the same figure, the liquid common supply path side is opened as described above, but the height of the opening where the liquid common supply path 17 and the liquid column resonance liquid chamber 18 communicate with each other (height h2 shown in FIG. 1). In comparison, the height of the frame serving as the fixed end (height h1 shown in FIG. 1) is about twice or more. Therefore, FIG. 6 shows temporal changes in velocity distribution and pressure distribution under the approximate condition that the liquid column resonance liquid chamber 18 is substantially fixed on both sides.

FIG. 6A shows a pressure waveform and a velocity waveform in the liquid column resonance liquid chamber 18 when droplets are discharged.
In FIG. 6B, the meniscus pressure increases again after the liquid is drawn immediately after the droplet is discharged. As shown in FIGS. 4A and 4B, the pressure in the flow path provided with the discharge hole 19 in the liquid column resonance liquid chamber 18 is maximum. Thereafter, as shown in FIG. 6C, the positive pressure in the vicinity of the ejection hole 19 decreases, and the liquid droplet 21 is ejected in a negative pressure direction.

  Then, as shown in FIG. 6D, the pressure in the vicinity of the discharge hole 19 is minimized. From this time, the filling of the toner composition liquid 14 into the liquid column resonance liquid chamber 18 starts. Thereafter, as shown in FIG. 6E, the negative pressure in the vicinity of the discharge hole 19 becomes smaller and shifts to the positive pressure direction. At this time, the filling of the toner composition liquid 14 is completed. Then, as shown in FIG. 6A again, the positive pressure in the droplet discharge region of the liquid column resonance liquid chamber 18 becomes maximum, and the droplet 21 is discharged from the discharge hole 19. As described above, a standing wave due to liquid column resonance is generated in the liquid column resonance liquid chamber by high-frequency driving of the vibration generating means. And since the discharge hole 19 is arrange | positioned in the droplet discharge area | region corresponded to the antinode of the standing wave by liquid column resonance which becomes a position where a pressure fluctuates the most, the droplet 21 corresponds to the period of the antinode. The ink is continuously discharged from the discharge hole 19.

  Next, an example of a configuration in which droplets are actually ejected by the liquid column resonance phenomenon will be described. This example is a resonance mode in which the length L between both ends in the longitudinal direction of the liquid column resonance liquid chamber 18 in FIG. 1 is 1.85 [mm] and N = 2, and the first to fourth discharge holes are provided. FIG. 7 shows a state in which a discharge hole is arranged at the antinode of the N = 2 mode pressure standing wave and a discharge performed with a sine wave with a drive frequency of 340 [kHz] is photographed by the laser shadowgraphy method. As can be seen from the figure, it was possible to discharge droplets with very uniform diameters and almost uniform speeds.

  FIG. 8 is a characteristic diagram showing droplet velocity frequency characteristics when driven by the same amplitude sine wave with a drive frequency of 290 [kHz] to 395 [kHz]. As can be seen from the figure, the discharge speed from each nozzle is uniform and the maximum discharge speed when the drive frequency is around 340 [kHz] in the first to fourth nozzles. From this result, it can be seen that, in the second mode of the liquid column resonance frequency, 340 [kHz], uniform ejection is realized at the antinode position of the liquid column resonance standing wave. Further, from the characteristic results of FIG. 7, the droplet is between the droplet discharge speed peak at 130 [kHz] which is the first mode and the droplet discharge speed peak at 340 [kHz] which is the second mode. It can be seen that the characteristic frequency characteristic of the liquid column resonance standing wave of the liquid column resonance that does not discharge is generated in the liquid column resonance liquid chamber.

[Droplet solidification]
The toner of the present invention can be obtained by solidifying and then collecting the droplets of the toner composition liquid discharged into the gas from the droplet discharge means described above.

[Droplet solidification means]
The means for solidifying the ejected droplets is different depending on the properties of the toner composition liquid, but any means can be used as long as it can basically make the toner composition liquid into a solid state.
For example, if the toner composition liquid is obtained by dissolving or dispersing a solid raw material in a volatile solvent, it can be achieved by drying the droplets in a conveying airflow after the droplets are jetted, that is, volatilizing the solvent. . In drying the solvent, the drying state can be adjusted by appropriately selecting the temperature, vapor pressure, gas type, and the like of the gas to be injected. Further, even if the particles are not completely dried, they may be additionally dried in a separate step after the collection as long as the collected particles maintain a solid state. Even if it does not follow the said example, you may achieve by application of a temperature change, a chemical reaction, etc.

[Solidification particle collection means]
The solidified particles can be recovered from the air by a known powder collecting means such as a cyclone or a back filter.

FIG. 9 is a cross-sectional view of an example of an apparatus for carrying out the toner manufacturing method of the present invention. The toner manufacturing apparatus 1 mainly includes a droplet discharge means 2 and a dry collection unit 60.
The droplet discharge means 2 supplies a raw material container 13 for storing the toner composition liquid 14 and the toner composition liquid 14 stored in the raw material container 13 to the droplet discharge means 2 through the liquid supply pipe 16. A liquid circulation pump 15 that pumps the toner composition liquid 14 in the liquid supply pipe 16 to return to the raw material container 13 through the liquid return pipe 22 is connected to the liquid droplet discharge means 2 as needed. Can supply. The liquid supply pipe 16 is provided with a pressure measuring device P1 and the dry collecting unit 60 is provided with a pressure measuring device P2. The liquid feeding pressure to the droplet discharge means 2 and the pressure in the dry collecting unit 60 are liquid pressures. It is managed by the meter P1 and the in-chamber pressure gauge P2. At this time, if the pressure p1 of the liquid pressure gauge P1 and the pressure p2 of the in-chamber pressure gauge P2 are in a relation of p1> p2, the toner composition liquid 1 may ooze out from the discharge hole 19, and p1 <p2. In this case, it is desirable that P1≈P2 because gas may enter the discharge means and stop the discharge.
In the chamber 61, a descending airflow 101 created from the carrier airflow inlet 64 is formed. The droplets 21 ejected from the droplet ejection means 2 are transported downward not only by gravity but also by the transport airflow 101 and are discharged from the transport airflow outlet 65 to collect the solidified toner particles. It is collected by the collecting means 62. The collected toner is stored in the toner storage unit 63.

[Conveyance airflow]
When the ejected droplets come into contact with each other before drying, the droplets coalesce and become one particle (hereinafter, this phenomenon is called coalescence). In order to obtain solidified particles having a uniform particle size distribution, it is necessary to maintain the distance between the ejected droplets. However, the ejected droplets have a constant initial velocity, but eventually become stalled due to air resistance. The jetted droplets catch up with the stalled particles and coalesce as a result. Since this phenomenon occurs constantly, the particle size distribution is greatly deteriorated when the particles are collected. In order to prevent coalescence, it is necessary to transport the liquid droplets while solidifying the droplets while preventing the liquid droplets from decreasing in speed and preventing the liquid droplets from coming into contact with each other while preventing the coalescence. Carry the solidified particles to the collection means.

For example, as shown in FIG. 1, a part of the transport airflow 101 is arranged as a first airflow in the vicinity of the droplet discharge means in the same direction as the droplet discharge direction, thereby reducing the droplet velocity immediately after the droplet discharge. Can be prevented and coalescence can be prevented. Alternatively, as shown in FIG. 10, it may be transverse to the discharge direction. Alternatively, although not shown, it may have an angle, and it is desirable to have an angle at which the droplets are separated from the droplet discharge means. As shown in FIG. 10, when the anti-adhesion airflow is applied from the lateral direction to the droplet discharge, it is desirable that the trajectories do not overlap when the droplets are conveyed by the anti-adhesion airflow from the discharge holes. .
After preventing coalescence by the first air stream as described above, the solidified particles may be carried to the solidified particle collecting means by the second air stream.

  It is desirable that the velocity of the first air flow is equal to or higher than the droplet jet velocity. If the speed of the anti-adhesion airflow is lower than the droplet ejection speed, it is difficult to exert the function of preventing the droplet particles, which is the original purpose of the anti-adhesion airflow, from contacting.

  The property of the first air stream can be added with a condition such that the droplets do not coalesce with each other, and may not necessarily be the same as the second air stream. Further, a chemical substance that promotes solidification of the particle surface may be mixed in the anti-adhesion airflow, or may be imparted in anticipation of a physical action.

  The carrier airflow 101 is not particularly limited as a state of the airflow, and may be a laminar flow, a swirl flow, or a turbulent flow. There is no particular limitation on the type of gas constituting the carrier airflow 101, and air or a nonflammable gas such as nitrogen may be used. Moreover, the temperature of the conveyance airflow 101 can be adjusted as appropriate, and it is desirable that there is no fluctuation during production. Also, means for changing the airflow state of the carrier airflow 101 in the chamber 61 may be taken. The carrier airflow 101 may be used not only to prevent the droplets 21 from being attached to each other but also to prevent the droplets 21 from adhering to the chamber 61.

[Secondary drying]
When the amount of residual solvent contained in the toner particles obtained by the dry collection unit 60 shown in FIG. 9 is large, secondary drying is performed as necessary to reduce this. As the secondary drying, general known drying means such as fluidized bed drying or vacuum drying can be used. If the organic solvent remains in the toner, not only the toner characteristics such as heat-resistant storage stability, fixing properties, and charging characteristics will change over time. Since the organic solvent volatilizes during fixing by heating, the possibility of adverse effects on the user and peripheral equipment is increased. Therefore, sufficient drying is performed.

Next, the toner will be described.
The toner of the present invention contains at least a binder resin, a release agent, and fine particles, and if necessary, a colorant, a charge adjusting agent, an additive, and other components.
The contact angle of the binder resin with water is 90 ° or less, and the degree of hydrophobicity of the fine particles with respect to methanol is 65% or more.

The “toner composition liquid” used in the present invention will be described. The toner composition liquid is in a liquid state in which the above toner components are dissolved or dispersed in a solvent, or may be free from a solvent as long as it is liquid under the conditions of ejection, and a part or all of the toner components are melted. In a liquid state.
As the toner material, the same toner as the conventional electrophotographic toner can be used as long as the above toner composition liquid can be prepared. As described above, the droplets are made into fine droplets by the droplet discharge means, and the target toner particles can be produced by the droplet solidification collecting means.

  The toner particles produced by the above means have a structure in which fine particles are unevenly distributed on the outermost surface of the toner. This is because the fine particles dispersed in the toner composition liquid are hydrophobic, so that they are spontaneously distributed at the gas-liquid interface in the drying process after the toner liquid is discharged. As a result, it is possible to omit the external addition process that is required in the known toner manufacturing process.

(Organic solvent)
The organic solvent is not particularly limited as long as it can dissolve the binder resin and stably disperse the dispersion such as the colorant, and can be appropriately selected according to the purpose. When collecting the toner with a cyclone, it is necessary to dry and collect the toner composition liquid in the gas phase to some extent. Therefore, a solvent that can be easily dried is preferable. From the viewpoint of drying, the boiling point of the solvent is preferably 100 ° C. or less.
As specific examples, toluene, ethyl acetate, butyl acetate, methyl ethyl ketone, methyl isobutyl ketone and the like can be used alone or in combination of two or more.

(Binder resin)
Conventionally known binder resins for toner are used as the binder resin, but those having no cross-linked structure are preferable because they are dissolved in a solvent.
For example, vinyl polymers comprising styrene monomers, acrylic monomers, methacrylic monomers, copolymers comprising two or more of these monomers, polyester resins, polyol resins, phenol resins , Polyurethane resin, polyamide resin, epoxy resin, xylene resin, terpene resin, coumarone indene resin, polycarbonate resin, petroleum resin, and the like.
Of these, polyester resins and copolymer resins of styrene monomers and (meth) acrylic monomers are preferably used.

  In order to dispose the inorganic fine particles on the outermost surface of the toner, it is desirable that the hydrophilicity of the resin is higher. The contact angle of the resin with respect to water is preferably 90 ° or less, more preferably 85 ° or less. When a resin having a contact angle larger than 90 ° is used, the inorganic fine particles are not easily exposed on the outermost surface of the toner, and heat resistant storage stability and fluidity are deteriorated. Expression (2) indicates that the contact angle of the toner varies between the contact angle of the toner before heat melting and the contact angle of the toner after heat melting. This is because the inorganic fine particles are unevenly distributed on the surface of the toner before heat melting, which is different from the properties of the toner surface made uniform by heat melting.

The following are mentioned as a monomer which comprises a polyester-type polymer.
Examples of the divalent alcohol component include ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 2-ethyl-1,3-hexanediol, hydrogenated bisphenol A, or diol obtained by polymerizing cyclic ethers such as ethylene oxide and propylene oxide to bisphenol A, etc. Is mentioned.

  Examples of the acid component that forms the polyester polymer include benzene dicarboxylic acids such as phthalic acid, isophthalic acid, and terephthalic acid or anhydrides thereof, alkyldicarboxylic acids such as succinic acid, adipic acid, sebacic acid, and azelaic acid, or Unsaturated dibasic acids such as anhydride, maleic acid, citraconic acid, itaconic acid, alkenyl succinic acid, fumaric acid, mesaconic acid, maleic anhydride, citraconic anhydride, itaconic anhydride, alkenyl succinic anhydride And the like, and the like. Examples of the trivalent or higher polyvalent carboxylic acid component include trimet acid, pyromet acid, 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxy-2-methyl-2-methylenecarboxypropane, tetra (methylene Carboxy) methane, 1,2,7,8-octanetetracarboxylic acid, emporic trimer acid, or their anhydrides, partial lower alkyl esters, etc. are mentioned, but a small amount is used in order not to give a crosslinked structure. I have to stay in it.

  Examples of the styrene monomer include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-phenylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, and pn-. Amyl styrene, p-tert-butyl styrene, pn-hexyl styrene, pn-octyl styrene, pn-nonyl styrene, pn-decyl styrene, pn-dodecyl styrene, p-methoxy styrene , Styrene such as p-chlorostyrene, 3,4-dichlorostyrene, m-nitrostyrene, o-nitrostyrene, p-nitrostyrene, or derivatives thereof.

  Examples of the acrylic monomer include acrylic acid, methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, n-octyl acrylate, n-dodecyl acrylate, and acrylic. Examples include 2-ethylhexyl acid, stearyl acrylate, 2-chloroethyl acrylate, acrylic acid such as phenyl acrylate, or esters thereof.

  Examples of the methacrylic monomer include methacrylic acid, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, n-dodecyl methacrylate, and methacrylic acid. And methacrylic acid or esters thereof such as 2-ethylhexyl, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, and the like.

  Examples of the polymerization initiator used in the production of the vinyl polymer or copolymer of the present invention include 2,2′-azobisisobutyronitrile, 2,2′-azobis (4-methoxy-2,4- Dimethylvaleronitrile), 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis (2-methylbutyronitrile), dimethyl-2,2′-azobisisobutyrate, 1 , 1′-azobis (1-cyclohexanecarbonitrile), 2- (carbamoylazo) -isobutyronitrile, 2,2′-azobis (2,4,4-trimethylpentane), 2-phenylazo-2 ′ , 4′-dimethyl-4′-methoxyvaleronitrile, 2,2′-azobis (2-methylpropane), methyl ethyl ketone peroxide, acetylacetone peroxide, Ketone peroxides such as rohexanone peroxide, 2,2-bis (tert-butylperoxy) butane, tert-butyl hydroperoxide, cumene hydroperoxide, 1,1,3,3-tetramethylbutyl Hydroperoxide, di-tert-butyl peroxide, tert-butylcumyl peroxide, dicumyl peroxide, α- (tert-butylperoxy) isopropylbenzene, isobutyl peroxide, octanoyl peroxide, decanoyl peroxide , Lauroyl peroxide, 3,5,5-trimethylhexanoyl peroxide, benzoyl peroxide, m-tolyl peroxide, di-isopropylperoxydicarbonate, di-2-ethylhexylpero Xidicarbonate, di-n-propyl peroxydicarbonate, di-2-ethoxyethyl peroxycarbonate, di-ethoxyisopropyl peroxydicarbonate, di (3-methyl-3-methoxybutyl) peroxycarbonate, acetylcyclo Hexylsulfonyl peroxide, tert-butyl peroxyacetate, tert-butyl peroxyisobutyrate, tert-butyl peroxy-2-ethylhexarate, tert-butyl peroxylaurate, tert-butyl-oxybenzoate, tert-butylperoxyisopropyl carbonate, di-tert-butylperoxyisophthalate, tert-butylperoxyallyl carbonate, isoamylperoxy-2-ethylhexanoate, di- tert- butylperoxy to hexa hydro terephthalate, tert- butylperoxy azelate, and the like.

  These binder resins preferably have a glass transition temperature (Tg) of 35 to 80 ° C., more preferably 40 to 75 ° C., from the viewpoint of toner storage stability. When Tg is lower than 35 ° C., the toner is likely to deteriorate in a high temperature atmosphere, and when Tg exceeds 80 ° C., the fixability may be lowered.

-Measurement method of exothermic peak temperature, melting point, and glass transition temperature (Tg)-
The heat generation peak temperature, melting point, and glass transition temperature (Tg) of the toner and each material in the present invention are measured using, for example, a DSC system (differential scanning calorimeter) (“DSC-60”, manufactured by Shimadzu Corporation). be able to.
Specifically, the exothermic peak temperature, melting point, and glass transition temperature of the target sample can be measured by the following procedure.
First, about 5.0 mg of a target sample is placed in an aluminum sample container, and the sample container is placed on a holder unit and set in an electric furnace. Next, the sample is heated from 0 ° C. to 200 ° C. at a heating rate of 10 ° C./min in a nitrogen atmosphere. Thereafter, the temperature is cooled to 0 ° C. at a temperature drop rate of 10 ° C./min from 200 ° C., and further heated to 200 ° C. at a temperature rise rate of 10 ° C./min, and a differential scanning calorimeter (“DSC-60”, manufactured by Shimadzu Corporation) ) To measure the DSC curve.
From the obtained DSC curve, using the analysis program “endothermic shoulder temperature” in the DSC-60 system, the DSC curve at the first temperature rise is selected, and the glass transition temperature at the first temperature rise of the target sample is obtained. Can do. Further, by using the “endothermic shoulder temperature”, a DSC curve at the second temperature rise can be selected, and the glass transition temperature at the second temperature rise of the target sample can be obtained.
Further, from the obtained DSC curve, the DSC curve at the first temperature rise is selected using the analysis program “peak temperature analysis program” in the DSC-60 system, and the melting point at the first temperature rise of the target sample is obtained. be able to. Further, by using the “endothermic peak temperature”, a DSC curve at the second temperature rise can be selected, and the melting point at the second temperature rise of the target sample can be obtained.
Similarly, using the “peak temperature analysis program”, a DSC curve at the first temperature drop can be selected, and the exothermic peak temperature at the first temperature drop of the target sample can be obtained.

In the present invention, the glass transition temperature at the first temperature rise when the toner is used as the target sample is Tg1st, and the glass transition temperature at the second temperature rise is Tg2nd.
Moreover, in this invention, melting | fusing point and Tg at the time of the 2nd temperature rise of each structural component are made into melting | fusing point and Tg of each object sample.

[Molecular weight distribution of binder resin]
In the molecular weight distribution of the binder resin by GPC (gel permeation chromatography), the presence of at least one peak in the region having a molecular weight of 3,000 to 50,000 is preferable in terms of toner fixing property and offset resistance. As the THF-soluble component, a binder resin in which a component having a molecular weight of 100,000 or less is 60 to 100 [%] is preferable, and a binder resin having at least one peak in a region having a molecular weight of 5,000 to 20,000 is used. More preferred.

―Measurement method of contact angle against water―
The contact angle is measured using an automatic contact angle meter (model number CA-W) manufactured by Kyowa Interface Chemical Co., Ltd. By selecting the “droplet method” in the device software, the wettability of the droplets adhering to the solid surface can be measured. The specific measurement method is in accordance with the measurement method of JIS R3257 sessile drop method.
-Preparation of sample plate for measuring contact angle of binder resin-
3 g of the binder resin was weighed into an aluminum cup with a flat bottom, and then placed in an oven heated to 120 ° C. and heated until the resin was sufficiently melted. Then, it cools until resin solidifies and takes out the resin plate from an aluminum cup, and obtains the sample plate for contact angle measurement. At this time, it was confirmed that the bottom surface of the sample plate had no defects such as irregularities and cracks that hindered measurement.
-Preparation of sample plate for toner contact angle measurement-
The sample plate was prepared by pressure molding the toner with an automatic pressure molding machine. The molding conditions are shown below.
Toner amount: 3 g
Load: 6t
Time: 60s
Molding die diameter: 40 mm
-Preparation of sample plate for contact angle measurement of toner after heat melting-
3 g of toner was weighed into an aluminum cup with a flat bottom and then placed in an oven heated to 120 ° C. and heated until the toner was fully melted. Thereafter, the toner was cooled until solidified, and the toner plate was taken out of the aluminum cup to obtain a sample plate for contact angle measurement. At this time, it was confirmed that the bottom surface of the sample plate had no defects such as irregularities and cracks that hindered measurement.

(Fine particles)
The fine particles are exposed on the toner surface and play a role of improving the fluidity of the toner.
Therefore, when the fine particles are polymer fine particles, they need not be dissolved in an organic solvent. If the condition is satisfied, the fine particles may be surface treated with, for example, a fluororesin powder such as fine vinylidene fluoride powder or polytetrafluoroethylene fine powder, a silane coupling agent, a titanium coupling agent, or silicone oil. Treated silica, treated titanium oxide, treated alumina, and the like. Among these, the treated silica is preferable because it does not dissolve in a solvent and the effect of imparting fluidity to the toner is high. As a treating agent for the silica, hexamethyldisilazane (HMDS) is highly effective in improving the degree of hydrophobicity. Is particularly preferred. The hydrophobicity of the treated silica is desirably 65% (MeOH) or more. If it is less than 65%, the silica is difficult to be exposed on the surface, and the fluidity and heat-resistant storage stability of the toner are deteriorated. The degree of hydrophobicity of silica can be controlled to some extent by the amount of the silane coupling agent, and the degree of hydrophobicity can be increased by increasing the amount.

―Measurement method of degree of hydrophobicity―
The degree of hydrophobicity is measured by a methanol titration test. The methanol titration test is an experimental test for confirming the degree of hydrophobicity of fine particles having a hydrophobized surface.
The methanol titration test will be described below by taking as an example the case of measuring the degree of hydrophobicity of silica fine powder having a hydrophobized surface.
-Put 50 ml of water in a 250 ml Erlenmeyer flask and add 0.2 g of silica fine particles.
-While gently stirring with a magnetic stirrer, methanol is added from a burette whose tip is immersed in water at the time of dropping.
・ When the total amount of silica fine powder is suspended in the liquid, the end point of titration is set.
The degree of hydrophobicity is expressed as the percentage of methanol in the liquid mixture of methanol and water when the end point is reached, as shown in the following formula.
Hydrophobicity (%)
= (Mass of dropwise methanol / (50 ml + mass of dropwise methanol)) × 100

(Coloring agent)
The colorant is not particularly limited, and a commonly used colorant can be appropriately selected and used. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide, ocher, yellow lead, titanium yellow, polyazo yellow, oil yellow, Hansa yellow ( GR, A, RN, R), Pigment Yellow L, Benzidine Yellow (G, GR), Permanent Yellow (NCG), Vulcan Fast Yellow (5G, R), Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL, Iso Indolinone Yellow, Bengala, Pangdan, Lead Red, Cadmium Red, Cadmium Mercury Red, Antimony Zhu, Permanent Red 4R, Para Red, Faise Red, Parachlor Ortho Nitroaniline Red, Resol Fast Scarlet G, Brilli Fast Scarlet, Brilliant Carmine BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pogment Scarlet 3B, Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thioindigo Red B, Thioindigo Maroon , Oil red, quinacridone red, pyrazolone red, polyazo red, chrome vermilion, benzidine oren , Perinone orange, oil orange, cobalt blue, cerulean blue, alkaline blue rake, peacock blue rake, Victoria blue rake, metal-free phthalocyanine blue, phthalocyanine blue, fast sky blue, indanthrene blue (RS, BC), indigo, Ultramarine blue, bitumen, anthraquinone blue, fast violet B, methyl violet lake, cobalt purple, manganese purple, dioxane violet, anthraquinone violet, chrome green, zinc green, chromium oxide, pyridian, emerald green, pigment green B, naphthol green B, green Gold, Acid Green Lake, Malachite Green Lake, Phthalocyanine Green, Anthraquinone Green, Titanium Oxide, Zinc white, litbon and mixtures thereof can be used.
The content of the colorant is preferably 1 to 15% by mass and more preferably 3 to 10% by mass with respect to the toner.

The colorant used in the present invention can also be used as a master batch combined with a resin. The binder resin kneaded with the master batch includes polyester resin, styrene such as polystyrene, poly p-chlorostyrene, polyvinyltoluene, and substituted polymers thereof; styrene-p-chlorostyrene copolymer, styrene-propylene copolymer Polymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate Copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, Styrene-vinyl Styrene copolymers such as tilketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester copolymer Combined; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin Aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax, and the like.
These may be used individually by 1 type, and 2 or more types may be mixed and used for them.

The master batch can be obtained by mixing and kneading a resin for a master batch and a colorant under a high shear force. At this time, an organic solvent can be used to enhance the interaction between the colorant and the resin. Also, there is a method of removing the water and organic solvent components by mixing and kneading an aqueous paste containing water, which is a so-called flushing method, together with a resin and an organic solvent, and transferring the colorant to the resin side. Since the wet cake can be used as it is, it does not need to be dried and is preferably used. For mixing and kneading, a high shearing dispersion device such as a three-roll mill is preferably used.
The amount of the master batch used is preferably 2 to 30 parts with respect to 100 parts of the binder resin.

  The resin for the masterbatch preferably has an acid value of 30 mgKOH / g or less, an amine value of 1 to 100 mgKOH / g, and a colorant dispersed therein. The acid value is 20 mgKOH / g or less, the amine value Is more preferably 10 to 50 mg KOH / g, and the colorant is dispersed and used. When the acid value exceeds 30 mgKOH / g, the chargeability under high humidity may be lowered, and the pigment dispersibility may be insufficient. Further, when the amine value is less than 1 mgKOH / g and when the amine value exceeds 100 mgKOH / g, the pigment dispersibility may be insufficient. The acid value can be measured by the method described in JIS K0070, and the amine value can be measured by the method described in JIS K7237.

  The dispersant is preferably highly compatible with the binder resin in terms of pigment dispersibility. Specific examples of commercially available products include “Ajisper PB821”, “Azisper PB822” (manufactured by Ajinomoto Fine Techno Co., Ltd.), “Disperbyk-2001” (manufactured by Big Chemie), “EFKA-4010” (manufactured by EFKA), and the like. It is done.

(Release agent)
The toner composition liquid used in the present invention contains a release agent together with a binder resin and a colorant.
There are no particular limitations on the release agent, and those that are usually used can be appropriately selected and used. For example, low molecular weight polyethylene, low molecular weight polypropylene, polyolefin release agent, microcrystalline release agent, paraffin release agent. Aliphatic hydrocarbon release agents such as mold agents, sazol release agents, oxides of aliphatic hydrocarbon release agents such as oxidized polyethylene release agents, or block copolymers thereof, candelilla release agents, carnauba Release agents, plant release agents such as wood wax and jojoba wax, animal release agents such as beeswax, lanolin, and whale wax, mineral release agents such as ozokerite, ceresin, and petrolatum, and montanic acid ester release agents Mold release agents mainly composed of fatty acid esters such as caster mold release agents. Deoxidized carnauba mold release agents and the like are partially or wholly deoxidized fatty acid esters.

  The melting point of the release agent is preferably 70 to 140 [° C.] and more preferably 70 to 120 [° C.] in order to balance the fixing property and the offset resistance. When it is 70 [° C.] or higher, the blocking resistance is not lowered, and when it is 140 [° C.] or lower, a good offset resistance effect is obtained.

  The total content of the release agent is preferably 0.2 to 20 parts, more preferably 0.5 to 10 parts, relative to 100 parts of the binder resin.

  In the present invention, the temperature of the peak top of the endothermic peak of the release agent measured by DSC (differential scanning calorimetry) is defined as the melting point of the release agent.

  As the DSC measuring device for the release agent or toner, it is preferable to perform measurement with a highly accurate internal heat input compensation type differential scanning calorimeter. As a measuring method, it carries out according to ASTM D3418-82. The DSC curve used in the present invention is one that is measured when the temperature is raised at a temperature rate of 10 [° C./min] after raising and lowering the temperature once and taking a previous history.

(Charge control agent)
The charge control agent used in the toner of the present invention is not particularly limited, but from the viewpoint of solubility in an organic solvent, a negative charge containing a polycondensate obtained by polycondensation reaction of phenols and aldehydes. It is preferable to use a neutral charge control agent.
The phenols are a group consisting of p-alkylphenol, p-aralkylphenol, p-phenylphenol, and p-hydroxybenzoic acid ester having one phenolic hydroxyl group and hydrogen bonded to the ortho position of the hydroxyl group. It contains at least one selected phenol compound, and as the aldehydes, aldehydes such as paraformaldehyde, formaldehyde, paraaldehyde, and furfural can be appropriately used.
Examples of the charge control agent that is commercially available include a charge control agent (Fujikura Kasei Co., Ltd.) containing an FCA-N type condensation polymer.

  Examples of the present invention are shown below, but the scope of the present invention is not limited by these Examples. In addition, "part" shown below represents a mass part and "%" represents the mass%.

(Synthesis of polyester resin)
-Synthesis of polyester resin A-
In a 5-liter four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple, 0.6 mol of bisphenol A propylene oxide adduct and bisphenol A ethylene oxide adduct 0. 6 mol was added as a carboxylic acid component, 0.9 mol of terephthalic acid, and tin octylate was added as an esterification catalyst, and subjected to a condensation polymerization reaction at 180 ° C. for 4 hours in a nitrogen atmosphere. Thereafter, 0.07 mol of trimellitic acid was added, the temperature was raised to 210 ° C., the mixture was reacted for 1 hour, and further reacted at 8 KPa for 1 hour to synthesize polyester resin A. The contact angle of this resin with water was 69 °, the mass average molecular weight was 25,000, and the glass transition point was 58 ° C.
-Synthesis of polyester resin B-
In a 5-liter four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple, 0.5 mol of bisphenol A propylene oxide adduct and bisphenol A ethylene oxide adduct 0. 5 mol was added as a carboxylic acid component, 0.9 mol of terephthalic acid, and tin octylate was added as an esterification catalyst, and subjected to a condensation polymerization reaction at 180 ° C. for 4 hours in a nitrogen atmosphere. Thereafter, 0.07 mol of trimellitic acid was added, the temperature was raised to 210 ° C., the mixture was reacted for 1 hour, and further reacted at 8 KPa for 1 hour to synthesize polyester resin A. The contact angle of this resin with water was 80 °, the mass average molecular weight was 75,000, and the glass transition point was 63 ° C.

(Styrene- (meth) acrylic resin)
Styrene-n-butyl acrylate copolymer resin was used. The contact angle of this styrene-n-butyl acrylate copolymer resin to water was 84 °, the weight average molecular weight was 45,000, and the glass transition temperature was 61 ° C.

(Silicone resin)
A silicone resin (Z-6018 manufactured by Toray Dow Corning) was used. The contact angle of this silicone resin with water was 97 °, the mass average molecular weight was 2000, and the glass transition point was 51 ° C.

-Hydrophobic silica A-
From the center of the two-fluid nozzle for slurry spraying provided in the center of the burner, a slurry consisting of 50 parts of metal silicon powder (average particle size 6.7 μm) and 50 parts of water is placed in the flame (temperature about 1800 ° C.). While spraying at a rate of 5 kg / hour, oxygen was supplied from the surrounding area.
The produced spherical silica powder was pneumatically transported to a collection line by a blower and collected by a bag filter.
After adding 250 g of spherical silica powder to a vibrating fluidized bed and fluidizing with air circulated by a suction blower, spraying 3.2 g of water and fluidly mixing for 5 minutes, HMDS (hexamethyldisilane), which is a silane coupling agent. Silazane) (5.3 g) was sprayed and fluidly mixed for 40 minutes to obtain [hydrophobic silica A].

-Hydrophobic silica B-
Hydrophobic silica A was produced in the same manner as hydrophobic silica A, except that 70 parts of metal silicon powder (average particle size: 6.7 μm) and 30 parts of water were used to obtain [hydrophobic silica B]. .

-Hydrophobic silica C-
700 parts of methanol, 46 parts of water and 55 parts of 28% ammonia water were added and mixed to obtain a mixed solution.
While this mixed solution was adjusted to 35 ° C. and stirred, 1300 parts of tetramethoxysilane and 470 parts of 5.4% aqueous ammonia were simultaneously added, and the former was added dropwise over 5 hours and the latter over 2 hours.
After the tetramethoxysilane was added dropwise, stirring was continued for 0.2 hours to hydrolyze to obtain a silica fine particle suspension.
To the resulting suspension, 550 parts of hexamethyldisilazane was added at room temperature, heated to 55 ° C. and reacted for 3 hours to trimethylsilylate the silica fine particles. This obtained [hydrophobic silica C].

-Hydrophobic silica D-
700 parts of methanol, 46 parts of water, and 55 parts of 28% aqueous ammonia were added and mixed.
While this solution was adjusted to 35 ° C. and stirred, 1300 parts of tetramethoxysilane and 470 parts of 5.4% aqueous ammonia were simultaneously added, and the former was added dropwise over 7 hours and the latter over 4 hours.
Stirring was continued for 0.5 hour after the addition of tetramethoxysilane to perform hydrolysis to obtain a suspension of silica fine particles.
To the resulting suspension, 550 parts of hexamethyldisilazane was added at room temperature, heated to 55 ° C. and reacted for 3 hours to trimethylsilylate the silica fine particles.
This obtained [hydrophobic silica D].

-Hydrophobic titanium oxide A-
It is a silane coupling agent after charging 250 g of titanium oxide (manufactured by Teika Co., Ltd.) into a vibrating fluidized bed and spraying 3.2 g of water while fluidizing with air circulated by a suction blower and fluidizing and mixing for 5 minutes. 5.3 g of isobutyltrimethoxysilane was sprayed and fluidly mixed for 40 minutes to obtain [hydrophobic titanium oxide A].
Table 1 shows physical property values of the obtained hydrophobic silicas A to D and [hydrophobic titanium oxide A].

(Preparation of colorant dispersion)
First, a carbon black dispersion as a colorant was prepared.
17 parts of carbon black (Rega L400; manufactured by Cabot) and 3 parts of a pigment dispersant were primarily dispersed in 80 parts of ethyl acetate using a mixer having stirring blades. As the pigment dispersant, Ajisper PB821 (manufactured by Ajinomoto Fine Techno Co., Ltd.) was used. The obtained carbon black primary dispersion was finely dispersed by a strong shearing force using a bead mill (LMZ type manufactured by Ashizawa Finetech Co., Ltd., zirconia bead diameter 0.3 mm), and aggregates of 5 μm or more were completely removed. A secondary dispersion of carbon black was prepared.

(Preparation of release agent dispersion)
Next, a release agent dispersion was prepared.
Carnauba release agent 18 parts and release agent dispersant 2 parts were primarily dispersed in 80 parts of ethyl acetate using a mixer having stirring blades. The primary dispersion was heated to 80 ° C. while stirring to dissolve the carnauba release agent, and then the temperature of the solution was lowered to room temperature to precipitate release agent particles so that the maximum diameter was 3 μm or less. As the release agent dispersant, a polyethylene release agent obtained by grafting a styrene-butyl acrylate copolymer was used. The obtained dispersion was further finely dispersed by a strong shearing force using a bead mill (LMZ type manufactured by Ashizawa Finetech Co., Ltd., zirconia bead diameter 0.3 mm) to prepare a maximum diameter of 1 μm or less.

(Preparation of toner composition liquid)
Next, each dispersion or solution is stirred for 10 minutes using a mixer having stirring blades so that the binder resin, silica, colorant, and release agent have the composition shown in Table 2. And uniformly dispersed to obtain a toner composition liquid. The pigment and release agent particles did not aggregate due to the shock caused by solvent dilution.

(Example A)
<Preparation of Toner A>
Using the toner production apparatus shown in FIGS. 1, 2, and 3A, the toner composition liquid A is ejected with droplets under the following conditions by the droplet ejection head using the liquid column resonance principle shown in FIG. It was. Thereafter, the liquid droplets were dried and solidified, collected by a cyclone, and then secondarily dried at 35 ° C. for 48 hours to prepare toner base particles A.
[Liquid column resonance conditions]
Resonance mode: N = 2
Length between both ends in the longitudinal direction of the liquid column resonance liquid chamber: L = 1.8 mm
Height of end of frame on liquid common supply path side of liquid column resonance liquid chamber: h1 = 80 μm
The height of the communication port of the liquid column resonance liquid chamber: h2 = 40 μm
[Toner base particle preparation conditions]
Dispersion specific gravity: ρ = 1.1 g / cm ³
Discharge hole shape: perfect circle Discharge hole diameter: 7.5 μm
Number of discharge holes: 4 per liquid column resonance liquid chamber Minimum distance between adjacent discharge hole centers: 130 μm (all equally spaced)
Dry air temperature: 40 ° C
Applied voltage: 10.0V
Drive frequency: 395 kHz

(Example B)
The toner composition liquid A of Example A was changed to the toner composition liquid B to obtain [Toner B]. Various characteristics of the toner and clogging of the nozzle during ejection were evaluated, and the results are summarized in Table 3.

(Example C)
The toner composition liquid A of Example A was changed to the toner composition liquid C to obtain [Toner C]. Various characteristics of the toner and clogging of the nozzle during ejection were observed, and the results are summarized in Table 3.

(Example D)
The toner composition liquid A of Example A was changed to the toner composition liquid D to obtain [Toner D]. Various characteristics of the toner and clogging of the nozzle during ejection were evaluated, and the results are summarized in Table 3.

(Example E)
The toner composition liquid A of Example A was changed to toner composition liquid E to obtain [Toner E]. Various characteristics of the toner and clogging of the nozzle during ejection were evaluated, and the results are summarized in Table 3.

(Example F)
The toner composition liquid A of Example A was changed to toner composition liquid F to obtain [Toner F]. Various characteristics of the toner and clogging of the nozzle during ejection were evaluated, and the results are summarized in Table 3.

(Example G)
[Toner G] was obtained by changing the toner composition liquid A of Example A to the toner composition liquid G. Various characteristics of the toner and clogging of the nozzle during ejection were evaluated, and the results are summarized in Table 3.

(Comparative Example A)
The toner composition liquid A of Example A was changed to the toner composition liquid H to obtain [Toner H]. Various characteristics of the toner and clogging of the nozzle during ejection were evaluated, and the results are summarized in Table 3.

(Comparative Example B)
The toner composition liquid A of Example A was changed to the toner composition liquid I to obtain [Toner I]. Various characteristics of the toner and clogging of the nozzle during ejection were evaluated, and the results are summarized in Table 3.

(Comparative Example C)
The toner composition liquid A of Example A was changed to toner composition liquid J to obtain [Toner J]. Various characteristics of the toner and clogging of the nozzle during ejection were evaluated, and the results are summarized in Table 3.

(Comparative Example D)
The toner composition liquid A of Example A was changed to the toner composition liquid K to obtain [Toner K]. Various characteristics of the toner and clogging of the nozzle during ejection were evaluated, and the results are summarized in Table 3.

(Comparative Example E)
The toner composition liquid A of Example A was changed to the toner composition liquid L to obtain [Toner L]. Various characteristics of the toner and clogging of the nozzle during ejection were evaluated, and the results are summarized in Table 3.

(Comparative Example F)
[Toner M] was obtained by changing the toner composition liquid A of Example A to the toner composition liquid M. Various characteristics of the toner and clogging of the nozzle during ejection were evaluated, and the results are summarized in Table 3.

(Comparative Example G)
[Toner N] was obtained by changing the toner composition liquid A of Example A to the toner composition liquid N. Various characteristics of the toner and clogging of the nozzle during ejection were evaluated, and the results are summarized in Table 3.

(Comparative Example H)
In Comparative Example H, the toner manufacturing method was changed. Toner base particles O were produced by the following procedure.
-Synthesis of styrene / acrylic resin fine particles-
In a reaction vessel in which a stir bar and a thermometer were set, 683 parts of water, 16 parts of sodium salt of ethylene oxide methacrylate adduct sulfate (Eleminol RS-30, manufactured by Sanyo Chemical Industries), 83 parts of styrene, 83 parts of methacrylic acid, When 110 parts of butyl acrylate and 1 part of ammonium persulfate were added and stirred at 400 rpm for 15 minutes, a white emulsion was obtained. The system was heated to raise the system temperature to 75 ° C. and reacted for 5 hours. Further, 30 parts of a 1% ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 5 hours, and an aqueous vinyl resin (a copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt). A dispersion [resin fine particle dispersion] was obtained. The glass transition temperature Tg of the styrene / acrylic resin fine particles A1 was 62 ° C.

-Synthesis of acrylic resin fine particles-
In a reaction vessel equipped with a stir bar and thermometer, 683 parts of water, 10 parts of distearyldimethylammonium chloride (cation DS, manufactured by Kao), 144 parts of methyl methacrylate, 50 parts of butyl acrylate, 1 part of ammonium persulfate, ethylene glycol When 4 parts of dimethacrylate was charged and stirred at 400 rpm for 15 minutes, a white emulsion was obtained. The mixture was heated to raise the temperature in the system to 65 ° C. and reacted for 10 hours. Further, 30 parts of a 1% ammonium persulfate aqueous solution was added and aged at 75 ° C. for 5 hours to obtain an aqueous dispersion (acrylic resin fine particle dispersion) of a vinyl resin (methyl methacrylate). The glass transition temperature Tg of the acrylic resin fine particles was 79 ° C.

― ―Preparation of aqueous medium phase― ―
660 parts by weight of water, 25 parts of the styrene / acrylic resin fine particle dispersion A1, 25 parts of a 48.5% by weight aqueous solution of sodium dodecyl diphenyl ether disulfonate (“Eleminol MON-7”; manufactured by Sanyo Chemical Industries), and ethyl acetate 60 The parts were mixed and stirred to obtain a milky white liquid (aqueous phase). Furthermore, 50 parts of acrylic resin fine particles were added to obtain [Aqueous Phase]. When observed with an optical microscope, several hundred μm aggregates were observed. When this aqueous medium phase was stirred at 8000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), it was confirmed by an optical microscope that the aggregates were loosened and could be dispersed into small aggregates of several μm. Accordingly, in the subsequent emulsification step of the toner material, it was expected that the acrylic resin fine particles were dispersed and adhered to the droplets of the toner material component. As described above, the acrylic resin fine particles are aggregated but are loosened by shearing in order to uniformly adhere to the toner surface.

-Emulsification / solvent removal-
To the container containing 980 parts of [Toner Composition Liquid O] shown in Table 2, 1200 parts of [Aqueous Phase] was added and mixed with a TK homomixer at 13,000 rpm for 20 minutes to obtain [Emulsified Slurry]. .
[Emulsion slurry] was put into a container equipped with a stirrer and a thermometer, and after removing the solvent at 30 ° C. for 8 hours, aging was carried out at 45 ° C. for 4 hours to obtain [dispersed slurry].

-Cleaning and drying-
[Dispersion slurry] After filtering 100 parts under reduced pressure,
(1): 100 parts of ion-exchanged water was added to the filter cake, mixed with a TK homomixer (10 minutes at 12,000 rpm), and then filtered.
(2): 100 parts of a 10% aqueous sodium hydroxide solution was added to the filter cake of (1), mixed with a TK homomixer (30 minutes at 12,000 rpm), and then filtered under reduced pressure.
(3): 100 parts of 10% hydrochloric acid was added to the filter cake of (2), mixed with a TK homomixer (rotation speed: 12,000 rpm for 10 minutes), and then filtered.
(4): The operations of (1) to (4) above, wherein 300 parts of ion-exchanged water is added to the filter cake of (3), mixed with a TK homomixer (10 minutes at 12,000 rpm) and then filtered. Was performed twice to obtain a [filter cake].
[Filter cake 1] was dried at 45 ° C. for 48 hours in a circulating drier, and sieved with a mesh of 75 μm to obtain [Toner O].

(Creation of carrier)
The following composition was dispersed with a homomixer for 20 minutes to prepare a coating layer forming solution. This coating layer forming liquid was coated on the surface of 1,000 parts of spherical magnetite having a particle diameter of 40 μm using a fluid bed type coating apparatus to obtain a magnetic carrier.
[composition]
Silicone resin (organostraight silicone) 100 parts Toluene 100 parts γ- (2-Aminoethyl) aminopropyltrimethoxysilane 5 parts Carbon black 10 parts

(Development of developer)
For each of [Toner A] to [Toner N], 4 parts of black toner and 96 parts of the magnetic carrier were mixed by a ball mill to prepare a two-component developer.
Each two-component developer was evaluated for particle size distribution, heat-resistant storage stability, and agent fluidity by the following methods.

(Evaluation of particle size distribution)
The volume average particle diameter (Dv) and number average particle diameter (Dn) of toner A to toner O were measured with an aperture diameter of 100 μm using a particle size measuring device (Multisizer III, manufactured by Beckman Coulter, Inc.), and analysis software ( The analysis was performed with a Beckman Coulter Multisizer 3 Version 3.51).
Specifically, 0.5 mL of 10% surfactant (alkylbenzene sulfonate Neogen SC-A, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was added to a glass beaker (100 mL volume). Next, 0.5 g of each toner was added, and after stirring with microspatel, 80 mL of ion-exchanged water was added. Subsequently, the dispersion process was performed for 10 minutes with an ultrasonic disperser (W-113MK-II, manufactured by Honda Electronics Co., Ltd.).
This dispersion was measured using the Multisizer III and Isoton III (manufactured by Beckman Coulter, Inc.) as the measurement solution. In the measurement, the toner dispersion was dropped so that the concentration indicated by Multisizer III was 8 ± 2%. The target particle size was 2.001 μm or more and 20.1874 μ or less.

  After measuring the volume and number of toner particles or toner, the volume distribution and number distribution were calculated. From the obtained distribution, the volume average particle diameter (Dv) and the number average particle diameter (Dn) of the toner were determined. As an index of the particle size distribution, Dv / Dn obtained by dividing the volume average particle diameter (Dv) of the toner by the number average particle diameter (Dn) was used. If it is completely monodispersed, Dv / Dn = 1, and the larger this value, the wider the distribution.

(Measurement of contact angle)
The contact angles CAa and CAb of the toner and the toner after heat melting were measured by the method described in the above section “Method for measuring contact angle with water”.

(Toner replenishability)
The toner replenishability from the toner container to the developing unit is determined by the state of toner replenishment while each toner is filled in the toner container and set in the machine, and the image is formed (the cumulative total is 20,000 sheets). Evaluation was made based on the following criteria.
[Evaluation criteria (replenishment)]
A: No abnormal replenishment was observed during the durability of the cumulative total of 20,000 sheets.
×: The toner end detection is turned on regardless of the toner in the toner container, and the machine is stopped.

-(Heat resistant storage stability)
A 50 ml glass container is filled with toner, left in a thermostatic bath at 50 ° C. for 24 hours, then cooled to 24 ° C., and the penetration is measured by a penetration test (JIS K2235-1991). The heat resistant storage stability was evaluated. In addition, the greater the penetration, the better the heat-resistant storage stability. When the penetration is less than 5 mm (x), there is a high possibility of problems in use.
〔Evaluation criteria〕
○: Needle penetration is 15 mm or more Δ: Needle penetration is 5 mm or more and less than 15 mm ×: Needle penetration is less than 5 mm

The toners A to G of Examples A to G were excellent in toner particle size distribution, heat resistant storage stability, and replenishment properties.
On the other hand, in Comparative Examples A to H, although the particle size distribution was excellent, the heat resistant storage stability and the replenishment properties were inferior. For Comparative Example A, the cause is that the contact angle of the resin is 90 ° or more, and for Comparative Examples B to G, the degree of hydrophobicity of silica is less than 65%. When the manufacturing method is changed in Comparative Example H, it can be seen that the value of CAa is very small, and hydrophilic components other than the hydrophobic fine particles are arranged on the surface. As a result, both the heat resistant storage stability and the replenishment properties were inferior.
When the surface state of the particles was observed with a scanning electron microscope (SEM), silica particles were observed on the toner surface in all of the toners of the examples. It was not exposed to.
FIG. 11 shows a TEM photograph of a cross section of the toner obtained in Example A.
Also from the measurement result by X-ray electron spectroscopy (XPS), it was detected that Si derived from the silica fine particles was unevenly distributed on the outermost surface.

The present invention includes the following embodiments (1) to (3).
(1) A resin particle manufacturing method comprising: a droplet discharge step of discharging a resin particle composition liquid from a discharge hole to form droplets; and a solidification step of solidifying the droplets, wherein the composition of the resin particles The liquid contains at least a binder resin, a release agent, and fine particles, the contact angle of the binder resin with respect to water is 90 ° or less, and the degree of hydrophobicity of the fine particles with respect to methanol is 65% or more. There is provided a method for producing resin particles.
(2) In the droplet forming step, vibration is applied to a thin film in which a plurality of discharge holes having the same opening diameter is formed by a vibrating means, and the resin particle composition liquid is discharged from the discharge holes to form droplets. The method for producing resin particles as described in (1) above, wherein
(3) The method for producing resin particles according to (1) or (2), wherein the fine particles are silica fine particles.

  The method for producing resin particles of the present invention can simplify the production process of resin particles, and obtain resin particles having a narrow particle size distribution, replenishability, and heat-resistant storage stability.

1: Toner manufacturing device
2: Droplet discharge means
9: Elastic plate
11: Liquid column resonance droplet discharge means
12: Airflow passage
13: Raw material container
14: Toner composition liquid
15: Liquid circulation pump
16: Liquid supply pipe
17: Liquid common supply path
18: Liquid column resonance liquid chamber
19: Discharge hole
20: Vibration generating means
21: Droplet
22: Liquid return pipe
24: Nozzle angle
41: Thin film
60: Dry collection unit
61: Chamber
62: Toner collecting means
63: Toner reservoir
64: Transport airflow inlet
65: Transport airflow outlet
101: Downstream
P1: Liquid pressure gauge
P2: Chamber pressure gauge

JP-A-7-152202 JP 2003-262976 A JP 2003-280236 A Japanese Patent Laid-Open No. 2003-262977 JP 2005-215089 A Japanese Patent Laid-Open No. 2005-215090 JP 2008-65005 A

Claims (3)

  A method for producing resin particles, comprising: a droplet discharge step of discharging a resin particle composition liquid from discharge holes to form droplets; and a solidification step of solidifying the droplets, wherein the resin particle composition liquid includes at least It comprises a binder resin, a release agent and fine particles, the contact angle of the binder resin with respect to water is 90 ° or less, and the degree of hydrophobicity of the fine particles with respect to methanol is 65% or more. A method for producing resin particles.   The droplet forming step is a step in which vibration is applied to a thin film having a plurality of discharge holes having the same opening diameter by a vibrating means, and the resin particle composition liquid is discharged from the discharge holes to form droplets. The method for producing resin particles according to claim 1, wherein:   The method for producing resin particles according to claim 1, wherein the fine particles are silica fine particles.