JP2015054307A - Grain production device, method for producing grain, grain and toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a grain having a sharp grain size distribution by preventing the fusion of droplets each other upon production of a grain by an injection granulation method.SOLUTION: Provided is a grain production device comprising: a droplet discharging means 11 of discharging a liquid 14 comprising the components of a grain as droplet 21; an air flow generating means of generating the air flow in the horizontal direction with respect to the discharging direction of the droplets 21; and a droplet solidifying means of solidifying the droplets to form a grain, including a turbulence generating means 25 at the upstream side of the air flow than a discharging hole 19.

Description

  The present invention relates to a method for producing particles of uniform size, and more particularly to a method for producing a toner for developing an electrostatic image used for developing an electrostatic image in electrophotography, electrostatic recording, electrostatic printing, and the like. It is about.

  Conventionally, as a method for producing an electrostatic charge image developing toner used in a copying machine, a printer, a fax machine, and a composite machine based on an electrophotographic recording method, only a pulverization method has been used in recent years. The method of forming toner particles in an aqueous medium has been widely used, and is surpassing the pulverization method. The toner produced by the polymerization method is called “polymerized toner” or “chemical toner” in some countries.

  The polymerization method is referred to as such because it involves the polymerization reaction of the toner raw material at the time of toner particle formation or in the process. Various polymerization methods have been put into practical use and include suspension polymerization, emulsion aggregation, polymer suspension (polymer aggregation), ester elongation reaction, and the like.

  In general, the toner obtained by the polymerization method is easier to obtain a smaller particle size, has a narrow particle size distribution, and has a nearly spherical shape compared to the toner obtained by the pulverization method. The image in is advantageous in that it is easy to obtain high image quality. However, on the other hand, it takes a long time for the polymerization process, and after completion of solidification, it is necessary to separate the solvent and toner particles, and then repeat washing and drying, which requires a lot of time, a lot of water and energy. There is.

  Therefore, there is known a jet granulation method in which a liquid in which a raw material component of toner is dissolved or dispersed in an organic solvent (hereinafter referred to as toner component liquid) is finely divided using various atomizers and then dried to obtain a powdery toner. (For example, refer to Patent Documents 1 to 3). According to this method, since it is not necessary to use water, steps such as washing and drying can be greatly reduced, so that the disadvantages of the polymerization method can be avoided.

  In the toner manufacturing methods disclosed in Patent Documents 1 to 3, droplets corresponding to the nozzle diameter are discharged from the nozzle. In this method, after the toner component liquid is sprayed, the droplets coalesce before the formed droplets are dried, and the solvent is dried in that state to obtain a toner, so that the resulting toner The particle size distribution was inevitably widened, and the particle size distribution was not satisfactory.

With respect to such a problem, the toner production method by jet granulation described in Patent Document 4 proposed by the present applicant does not require a large amount of cleaning liquid, repeated separation of solvent and particles, and is extremely efficient in production. Toner with high particle size, energy saving, and narrow particle size distribution.
However, in the method described in Patent Document 4, when the droplet discharge amount is increased in order to improve the productivity of the fine particles, the droplet concentration in the discharge unit increases, and the droplets coalesce. One droplet was dried to form coarse particles, and the problem was that the uniformity of the particle diameter, which is a feature of this method, was impaired.

  Therefore, the present invention has been made in view of the above problems, and in the method for producing an electrostatic charge image developing toner by the jet granulation method, the density of the droplets after spraying is reduced and the droplets are combined. An object of the present invention is to provide a method for producing a toner for developing an electrostatic image having a narrow particle size distribution.

The features of the present invention, which is a means for solving the above problems, are as described below.
Droplet discharge means for discharging a liquid containing the constituent components of particles as droplets;
An airflow generating means for generating an airflow transverse to the discharge direction of the droplets;
Droplet solidifying means for solidifying the droplet to form particles;
An apparatus for producing particles having
An apparatus for producing particles having a turbulent flow generating member on the upstream side of the airflow from the discharge hole.

The present invention, which is a means for solving the above problems, has the following specific effects.
With the particle production apparatus of the present invention, it is possible to prevent coalescence of droplets and thus obtain particles having an extremely narrow particle size distribution that could not be obtained by conventional methods.

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 outlet. 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 an example of the liquid column resonance droplet formation means for implementing this invention.

  EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated based on drawing. Note that it is easy for a person skilled in the art to make other embodiments by changing or correcting the present invention within the scope of the claims, and these changes and modifications are included in the scope of the claims. The following description is an example of the best mode of the present invention, and does not limit the scope of the claims.

  An example of the particle production apparatus of the present invention will be described below with reference to FIGS. The particle production apparatus of the present invention is divided into a droplet discharge means and a droplet solidification collecting means. Each is explained below.

[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 column resonance type discharge means that discharges using the resonance of the liquid column will be described.
FIG. 1 shows a liquid column resonance droplet discharge means 11. The liquid common supply path 17 and the liquid column resonance liquid chamber 18 are included. 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).

  In the present invention, a liquid containing components that form particles is referred to as a “particle component liquid”. The particle component liquid is discharged from the discharge means and may be a liquid under the discharge conditions. The particle component liquid discharged from the discharge means in the present invention may be in a state in which the component of the particle to be obtained is dissolved or dispersed, and is in a state where the particle component is melted without containing a solvent. May be. In the following, the present invention will be described taking as an example the case of producing toner particles as particles. Hereinafter, a liquid containing a component that forms toner particles is referred to as a “toner component liquid”.

  The toner component 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 component 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 component 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 component 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 component liquid 14 supplied from the path 17 increases, and the toner component liquid 14 is replenished into the liquid column resonance liquid chamber 18. When the toner component liquid 14 is replenished in the liquid column resonance liquid chamber 18, the flow rate of the toner component 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]. If the particle size is smaller than 1 [μm], the formed droplets may be very small, so that the toner may not be obtained. In the case of a configuration in which solid fine particles such as pigment are contained as a component of the toner, the discharge hole 19 There is a risk that productivity will be reduced due to frequent blockages. When the particle diameter is larger than 40 [μm], the droplet diameter is large, and when this is dried and solidified to obtain a desired toner particle diameter of 3 to 6 μm, the toner composition is diluted with an organic solvent into a very dilute liquid. In some cases, a large amount of drying energy is required to obtain a certain amount of toner, which is inconvenient. 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 such a shape that the opening diameter becomes narrow while having a round shape from the liquid contact surface of the discharge hole 19 toward the discharge port, 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 narrower at a certain angle from the liquid contact surface of the discharge hole 19 toward the discharge port, and the nozzle angle 44 can be appropriately changed. 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 this nozzle angle similar to (a), but the range of 60 to 90 ° is preferable. When the angle is 60 ° or less, it is difficult to apply pressure to the liquid and it is difficult to process the thin film 41, which is not preferable. When the nozzle angle 44 is 90 °, (c) corresponds, but it is difficult to apply pressure to the outlet, so 90 ° is the maximum value. If the angle is 90 ° or more, no pressure is applied to the outlet of the hole 12, so that the droplet discharge becomes very unstable.
(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 component liquid in the liquid column resonance liquid chamber is c, and vibration is generated. When the driving frequency given from the means 20 to the toner component liquid that is 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 with 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 at which the moving speed of the medium (liquid) in the longitudinal direction becomes zero, and conversely, the pressure becomes maximum. Conversely, the closed end is defined as an end where the moving speed of the medium becomes zero. 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 the waves, but it also stands depending on the number of discharge ports and the opening position of the discharge ports. The wave pattern fluctuates, and a resonance frequency appears at a position deviated from the position obtained from Equation 3 above. 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 from the above equation (2) as 324 kHz. 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 from the above equation (2) as 648 kHz. 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 port, the opening arrangement position, and the cross-sectional shape of the discharge port are factors that determine the drive frequency, and the drive frequency can be appropriately determined according to this. For example, when the number of discharge ports is increased, the restriction at the tip of the liquid column resonance liquid chamber, which has been the fixed end, gradually loosens, a resonant 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 port that is closest to the liquid supply channel is a starting point, and the loose restriction condition is applied.The cross-sectional shape of the discharge port is round or the volume of the discharge port varies depending on the frame thickness. 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 port 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 port.

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. When the number exceeds 100, if a desired droplet is to be formed from the 100 ejection holes 19, it is necessary to set a high voltage to the vibration generating means 20, and the behavior of the piezoelectric body as the vibration generating means 20 is increased. Becomes unstable. 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. When the pitch between the discharge holes is smaller than 20 [μm], there is a high probability that the droplets discharged from the adjacent discharge holes collide with each other to form large droplets, leading to deterioration in the toner particle size distribution.

  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, filling of the liquid component resonance liquid chamber 18 with the toner component liquid 14 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 component 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 component 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 component liquid, but any means can be used as long as it can basically make the toner component liquid solid.
For example, if the toner component liquid is obtained by dissolving or dispersing a solid raw material in a volatile solvent, this can be achieved by drying the droplets in a carrier stream 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 unit 2 and a dry collection unit 60.
The dry collection unit 60 includes a chamber 61, a toner collection unit 62, and a toner storage unit 63.
The droplet discharge means 2 supplies a raw material container 13 for storing the toner component liquid 14 and the toner component 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 component 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 is provided with a pressure measuring device P2. The pressure of the liquid feeding to the droplet discharge means 2 and the pressure in the dry collecting means 60 are the pressure gauge P1, Managed by P2. At this time, if the relationship of P1> P2, the toner component liquid 1 may ooze out from the discharge port 19, and if P1 <P2, gas may enter the discharge means and the discharge may stop. , P1≈P2.
In the chamber 61, a descending airflow 101 created from the carrier airflow inlet 64 is formed. The droplets 21 discharged from the droplet discharge means 2 are transported downward not only by gravity but also by the transport airflow 101, collected by the solidified particle collecting means 62, and stored in the particle storage means 63. be able to. The toner stored in the toner storage unit 63 is dried in a further step as necessary.

[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.

As shown in FIG. 1, by causing the first air flow to act from the lateral direction with respect to the ejection direction, it is possible to prevent a drop in the droplet speed immediately after the droplet is ejected and to prevent coalescence. As described above, when the anti-attachment airflow is applied from the lateral direction with respect to the droplet discharge direction, it is desirable that the trajectories do not overlap when the droplets are conveyed from the discharge port by the anti-attachment airflow.
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 physical action.

  In the present invention, as shown in FIG. 10, the air flow path 12 is provided with a member 25 (hereinafter referred to as a turbulent flow generating member) that partially blocks the airflow upstream of the airflow from the discharge hole. By providing this member, a turbulent flow field is locally formed at a position away from the transport path wall surface, and turbulent flow is generated only at a position where the droplet trajectory is bent. By generating turbulent flow in this manner, the droplets can be diffused without polluting the nozzle surface, so that the coalescence of the droplets can be reduced.

The turbulent flow generating member 25 is preferably arranged in the vicinity of the discharge hole, and the position thereof is arranged before the air flow hits the discharged droplet, that is, upstream. Moreover, the position is arrange | positioned upstream in the range of 0 mm to 5 mm. When the turbulent flow generating member 25 is arranged downstream of the discharge hole, the droplet collides with the turbulent flow generating member 25 during discharge and the resin component is deposited, thereby impairing discharge stability.
In addition, if it is more than 5mm away from the discharge hole and away from the upstream side, the turbulent flow area is greatly expanded, and droplets adhering to the discharge hole surface are generated. Detract from sex.
At the same time, it is desirable to arrange the turbulent flow generating member 25 at a position within the range of 1 mm to 5 mm in the downward direction of FIG. If the distance is less than 1 mm, the droplets are not completely bent in the direction of the air flow, and droplet collision occurs as in the above-described phenomenon.
If the distance exceeds 5 mm, the droplet does not exist in the turbulent region, and the effect is not exhibited.
Next, the shape of the turbulent flow generating member 25 is preferably a columnar shape, and it is desirable that the wake of the column is uniformly disturbed in the depth direction of FIG.
The state in which the turbulent flow is formed can be confirmed by observing particles from the lateral direction with respect to the air flow using a CCD camera.

The Reynolds number of the turbulent flow generating means is preferably 300 or more.
The Reynolds number is represented by the following (formula 6).
v: Relative average velocity with respect to the flow of the object (carrier air flow rate [m ³ / s] / air channel cross-sectional area [m ² ]) [m / s]
L: Representative linear dimension (diameter in the case of a cylinder) [m]
μ: Fluid viscosity [Pa · s]
ρ: Fluid density [kg / m ³ ]

As shown in Equation 6 above, the Reynolds number is determined by the average velocity relative to the droplet flow, that is, the velocity of the carrier airflow, the representative linear dimension of the air flow path, and the viscosity and density of the fluid carrying the droplet.
Therefore, the Reynolds number can be controlled by the carrier air velocity, the linear dimension of the air channel, and the fluid type.

  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 means 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 manufactured by the fine particle manufacturing apparatus of the present invention will be described.
The toner of the present invention contains at least a resin and a wax, and further contains a colorant when a colored toner is produced. Further, it contains a charge adjusting agent, additives and other components as required.

The “toner component liquid” used in the present invention will be described. The toner component liquid may be in a liquid state in which the toner component is 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 component is in a molten state. In a liquid state.
As the toner material, if the above-described toner component liquid can be prepared, the same toner material as that of a conventional electrophotographic toner can be used. 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.

〔resin〕
Examples of the resin include at least a binder resin.
The binder resin is not particularly limited, and a commonly used resin can be appropriately selected and used. For example, a styrene monomer, an acrylic monomer, a methacrylic monomer, etc. Vinyl polymers, copolymers of these monomers or two or more types, polyester polymers, polyol resins, phenol resins, silicone resins, polyurethane resins, polyamide resins, furan resins, epoxy resins, xylene resins, terpene resins , Coumarone indene resin, polycarbonate resin, petroleum resin, and the like.

As the properties of the binder resin, it is desirable to dissolve in a solvent, and it is desirable to have a conventionally known performance except for this feature.
[Molecular weight distribution of binder resin]
The molecular weight distribution of the binder resin by GPC (gel permeation chromatography) preferably has at least one peak in the region of molecular weight of 3,000 to 50,000 from the viewpoint 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 also preferable, and the binder resin has at least one peak in a molecular weight region of 5,000 to 20,000. Is more preferable.

[Acid value of binder resin]
What has 60 [mass%] or more of resin whose acid value of binder resin has 0.1-50 [mgKOH / g] is preferable.
In the present invention, the acid value of the binder resin component of the toner composition is measured according to JIS K-0070.

[Magnetic material]
As the magnetic material that can be used in the present invention, known magnetic materials conventionally used for electrophotographic toners can be used. For example, (1) iron oxide containing magnetic iron oxide such as magnetite, maghemite and ferrite, and other metal oxides, (2) metals such as iron, cobalt, nickel, or these metals and aluminum, cobalt, copper Alloys with metals such as lead, magnesium, tin, zinc, antimony, beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, vanadium. (3) and mixtures thereof are used. The magnetic material can also be used as a colorant. As the usage-amount of the said magnetic body, 10-200 mass parts of magnetic bodies are preferable with respect to 100 mass parts of binder resin, and 20-150 mass parts is more preferable. The number average particle diameter of these magnetic materials is preferably 0.1 to 2 [μm], more preferably 0.1 to 0.5 [μm]. The number average diameter can be obtained by measuring a photograph taken with a transmission electron microscope with a digitizer or the like.

[Colorant]
The colorant is not particularly limited, and a commonly used resin can be appropriately selected and used.

  The content of the colorant is preferably 1 to 15 [% by mass] and more preferably 3 to 10 [% by mass] based on the toner.

  The colorant used in the toner according to the present invention can also be used as a master batch combined with a resin. The master batch is for dispersing the pigment in advance, and may not be used if sufficient dispersion of the pigment is obtained. In general, a master batch is obtained by dispersing a pigment in hardness in a resin by applying high shear to the pigment and the resin. A conventionally well-known thing can be used as binder resin knead | mixed with manufacture of a masterbatch or a masterbatch. These may be used individually by 1 type, and 2 or more types may be mixed and used for them.

  As the usage-amount of the said masterbatch, 0.1-20 mass parts is preferable with respect to 100 mass parts of binder resin.

  A dispersant may be used to increase the dispersibility of the pigment during the production of the masterbatch. From the viewpoint of pigment dispersibility, it is preferable that the compatibility with the binder resin is high, and conventionally known ones can be used. Specific examples of commercially available products include “Ajisper PB821”, “Azisper PB822” (Ajinomoto Fine). Techno), “Disperbyk-2001” (by Big Chemie), “EFKA-4010” (by EFKA), and the like.

  The dispersant is preferably blended in the toner at a ratio of 0.1 to 10 [mass%] with respect to the colorant. When the blending ratio is less than 0.1 [% by mass], the pigment dispersibility may be insufficient, and when more than 10 [% by mass], the chargeability under high humidity may be deteriorated.

  The addition amount of the dispersant is preferably 1 to 200 parts by mass, more preferably 5 to 80 parts by mass with respect to 100 parts by mass of the colorant. If it is less than 1 part by mass, the dispersibility may be lowered, and if it exceeds 200 parts by mass, the chargeability may be lowered.

<Wax>
The toner component liquid used in the present invention contains a wax together with a binder resin and a colorant.
The wax is not particularly limited and can be appropriately selected from commonly used ones such as low molecular weight polyethylene, low molecular weight polypropylene, polyolefin wax, microcrystalline wax, paraffin wax, and sazol wax. Oxides of aliphatic hydrocarbon waxes such as aliphatic hydrocarbon waxes, polyethylene oxide waxes or block copolymers thereof, plant waxes such as candelilla wax, carnauba wax, wood wax, jojoba wax, beeswax, lanolin Waxes mainly composed of fatty acid esters such as animal waxes such as whale wax, mineral waxes such as ozokerite, ceresin, and petrolatum, and montanic acid ester waxes and castor waxes. Deoxidized carnauba wax and other fatty acid esters that have been partially or wholly deoxidized are included.

  The melting point of the wax is preferably 70 to 140 [° C.] and more preferably 70 to 120 [° C.] in order to balance the fixability and the offset resistance. If it is less than 70 [° C.], the blocking resistance may be lowered, and if it exceeds 140 [° C.], the offset resistance effect may be difficult to be exhibited.

  The total content of the wax is preferably 0.2 to 20 parts by mass and more preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the binder resin.

  In the present invention, the temperature of the peak top of the endothermic peak of the wax measured by DSC (Differential Scanning Calorimetry) is defined as the melting point of the wax.

  The wax or toner DSC measuring device is preferably measured with a high-precision 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.

[Other additives]
In the toner according to the present invention, as other additives, protection of the electrostatic latent image carrier / carrier, improvement of cleaning properties, adjustment of thermal characteristics / electrical characteristics / physical characteristics, resistance adjustment, softening point adjustment, fixing rate For the purpose of improvement, various metal soaps, fluorosurfactants, dioctyl phthalate, tin oxide, zinc oxide, carbon black, antimony oxide, etc. as conductivity imparting agents, and inorganic such as titanium oxide, aluminum oxide, alumina A fine powder or the like can be added as necessary. These inorganic fine powders may be hydrophobized as necessary. In addition, lubricants such as polytetrafluoroethylene, zinc stearate, polyvinylidene fluoride, abrasives such as cesium oxide, silicon carbide, strontium titanate, anti-caking agents, white particles and black particles having opposite polarity to the toner particles, Can also be used in small amounts as a developability improver.

  These additives have a silicone varnish, various modified silicone varnishes, silicone oil, various modified silicone oils, silane coupling agents, silane coupling agents having functional groups, and other organosilicons for the purpose of charge control and the like. It is also preferable to treat with a treating agent such as a compound or various treating agents.

  As the additive, inorganic fine particles can be preferably used. As said inorganic fine particle, well-known things, such as a silica, an alumina, a titanium oxide, can be used, for example.

  In addition, polymer fine particles such as polystyrene obtained by soap-free emulsion polymerization, suspension polymerization and dispersion polymerization, methacrylic acid ester and acrylic acid ester copolymer, polycondensation system such as silicone, benzoguanamine and nylon, thermosetting resin And polymer particles.

  Such external additives (additives) can be made hydrophobic by the surface treatment agent and prevent deterioration of the external additive itself even under high humidity. Examples of the surface treatment agent include a silane coupling agent, a silylating agent, a silane coupling agent having a fluorinated alkyl group, an organic titanate coupling agent, an aluminum coupling agent, silicone oil, a modified silicone oil, Etc. are preferable.

  The primary particle diameter of the external additive is preferably 5 [nm] to 2 [μm], and more preferably 5 [nm] to 500 [nm]. Moreover, as a specific surface area by BET method, it is preferable that it is 20-500 [m2 / g]. The use ratio of the inorganic fine particles is preferably 0.01 to 5 [% by weight] of the toner, and more preferably 0.01 to 2.0 [% by weight].

  Examples of the cleaning property improver for removing the developer after transfer remaining on the electrostatic latent image carrier or the primary transfer medium include fatty acid metal salts such as zinc stearate, calcium stearate, stearic acid, and polymethyl methacrylate. There may be mentioned polymer fine particles produced by soap-free emulsion polymerization such as fine particles and polystyrene fine particles. The polymer fine particles preferably have a relatively narrow particle size distribution and a volume average particle size of 0.01 to 1 [μm].

The volume average particle diameter of the toner according to the present invention is preferably 1 μm to 8 μm from the viewpoint of forming a high-resolution, high-definition and high-quality image.
Further, the particle size distribution (volume average particle size / number average particle size) of the toner is preferably 1.00 to 1.15 from the viewpoint of maintaining a stable image over a long period of time.

  Further, in the volume-based particle size distribution, it is preferable to have the second peak particle size at a particle size at least 1.21 to 1.31 times the mode diameter. When the second peak particle size is not provided, particularly when the (weight average particle size / number average particle size) is close to 1.00 (monodisperse), the fine packing property of the toner is very high. Therefore, initial fluidity deterioration and poor cleaning are likely to occur. Further, when the peak particle size is larger than 1.31 times, the image quality granularity is lowered due to the presence of a large amount of coarse powder as a toner, which is not preferable.

Moreover, although this invention concerns on the manufacturing apparatus of the following particle | grains (1), following (2)-(8) is also included as embodiment.
(1) droplet discharge means for discharging a liquid containing the constituent components of particles as droplets;
An airflow generating means for generating an airflow transverse to the discharge direction of the droplets;
Droplet solidifying means for solidifying the droplet to form particles;
An apparatus for producing particles having
An apparatus for producing particles having a turbulent flow generating member on the upstream side of the airflow from the discharge hole.
(2) The turbulent flow generating member is a columnar body having a circular or polygonal cross section, and is arranged such that the length direction of the columnar body is perpendicular to the discharge direction and the airflow direction. The particle production apparatus according to (1).
(3) The apparatus for producing particles according to (2), wherein the turbulent flow generating member is arranged in an upstream side of 0 mm or more and 5 mm or less from the discharge hole in the direction of the airflow.
(4) The particle production apparatus according to (2) or (3), wherein the turbulent flow generating member is disposed 1 mm or more and 5 mm or less away from the discharge hole in the droplet discharge direction.
(5) The apparatus for producing particles according to any one of (1) to (4), wherein the Reynolds number of the turbulent flow generating means is 300 or more.
(6) A method for producing particles, comprising producing particles using the particle production apparatus according to any one of (1) to (5).
(7) A method for producing an electrostatic image developing toner, comprising producing the electrostatic image developing toner using the particle production apparatus according to any one of (1) to (5).
(8) Particles produced by the method for producing particles according to (6), wherein the particle size distribution has a particle size distribution having a maximum peak at a diameter 1.26 times the mode diameter. particle.

The present invention will be described below in more detail based on examples, but the technical scope of the present invention is not limited to the following examples.
Moreover, in the following description, unless otherwise specified, parts indicate parts by mass.

Next, the formulation of the dissolution or dispersion used in the embodiment is shown.
The injection conditions are as described above.
-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 added to 80 parts of ethyl acetate, and primary dispersion was performed using a mixer having stirring blades. As the pigment dispersant, Ajisper PB821 (manufactured by Ajinomoto Fine Techno Co., Ltd.) was used. The obtained primary dispersion is 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 the secondary dispersion in which aggregates of 5 μm or more are completely removed. A liquid was prepared.

-Preparation of wax dispersion-
Next, a wax dispersion was prepared.
18 parts of carnauba wax and 2 parts of wax dispersant were added to 80 parts of ethyl acetate, and primary dispersion was performed using a mixer having stirring blades. The primary dispersion was heated to 80 ° C. with stirring to dissolve the carnauba wax, and then the liquid temperature was lowered to room temperature to precipitate wax particles so that the maximum diameter was 3 μm or less. As the wax dispersant, a polyethylene wax grafted with 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 dissolution or dispersion-
Next, a toner component liquid having the following composition to which a resin as a binder resin, the colorant dispersion, and the wax dispersion were added was prepared.
100 parts of a polyester resin as a binder resin, 30 parts of the colorant dispersion, and 30 parts of a wax dispersion are added to 840 parts of ethyl acetate, and stirred for 10 minutes using a mixer having stirring blades. Dispersed. Pigments and wax particles did not aggregate due to shock due to solvent dilution.

-Toner production equipment-
Toner was manufactured using the toner manufacturing apparatus 1 having the configuration shown in FIG.
The size and conditions of the components of the toner production apparatus are described below.

--Liquid column resonance droplet discharge means--
As a nozzle for discharging droplets, a nickel plate having a thickness of 28 μm and a discharge port (nozzle) having a diameter of 8.0 μm formed by electroforming was used.
The length L between both longitudinal ends of the liquid column resonance liquid chamber 18 is 1.85 [mm], N = 2 resonance mode, and the first to eighth discharge holes are N = 2 mode pressure standing. The thing which has arrange | positioned the discharge hole in the position of the antinode of the wave was used. The drive signal generation source was a NF company function generator WF 1973, which was connected to the vibration generation means with a polyethylene-coated lead wire. The driving frequency at this time is 352 [kHz] according to the liquid resonance frequency.

-Toner collection part-
The chamber 61 has an inner diameter of φ400 mm and a height of 2000 mm, and is vertically fixed. The upper end and the lower end are narrowed, the diameter of the carrier airflow inlet is φ50 mm, and the diameter of the carrier airflow outlet is φ50 mm. is there. The droplet discharge means 2 is disposed at the center of the chamber 61 at a height of 300 mm from the upper end in the chamber 61. The carrier airflow was 10.0 m / s and 40 ° C. nitrogen.

Example 1
Using the toner production apparatus described above, the produced toner component liquid was discharged, and the toner particles dried and solidified in the chamber were collected by a cyclone collector.
In FIG. 10, the turbulent flow generating member was cylindrical, and the diameter of the circle was 0.5 mm. Further, the center position of the cylinder was 2.0 mm below the discharge hole (Y = 2.0 mm) and 0.5 mm (X = −0.5 mm) upstream from the discharge hole. The air velocity was 14 m / s.
The toner was taken out of the toner storage container 63 to obtain the toner of Example 1.
The obtained toner was evaluated for particle size distribution and fine line evaluation by the following evaluation methods.
The average of the volume average particle diameter (Dv) was 5.2 μm, the average of the number average particle diameter (Dn) was 4.9 μm, and Dv / Dn was 1.06. The evaluation of fine line reproducibility was A.

<Evaluation of particle size distribution>
The particle size distribution of the toner was measured using a flow particle image analyzer (Sysmex Corp. FPIA-3000) under the following measurement conditions, and this was repeated three times.

A measurement method using a flow particle image analyzer (Flow Particle Image Analyzer) will be described below. The measurement of toner, toner particles and external additives using a flow type particle image analyzer can be performed using, for example, a flow type particle image analyzer FPIA-3000 manufactured by Toa Medical Electronics Co., Ltd.
The measurement is performed by removing fine dust through a filter, and as a result, in ^10-3 water of 10 ⁻³ cm ³ of water having a measurement range (for example, an equivalent circle diameter of 0.60 μm or more and less than 159.21 μm) of 20 particles or less. Add a few drops of a nonionic surfactant (preferably Contaminone N manufactured by Wako Pure Chemical Industries, Ltd.), add 5 mg of a measurement sample, and under conditions of 20 kHz and 50 W / 10 cm ^{3 with} an ultrasonic dispersing device STM UH-50. Dispersion treatment is performed for 1 minute, and further, dispersion treatment is performed for a total of 5 minutes, and a sample dispersion liquid in which the particle concentration of the measurement sample is 4000 to 8000 particles / ⁻³ cm ³ (for particles in the diameter range corresponding to the measurement circle) Then, the particle size distribution of particles having an equivalent circle diameter of 0.60 μm or more and less than 159.21 μm is measured.

The sample dispersion liquid is passed through a flow path (expanded along the flow direction) of a flat and flat transparent flow cell (thickness: about 200 μm). In order to form an optical path that passes across the thickness of the flow cell, the strobe and the CCD camera are mounted on the flow cell so as to be opposite to each other. While the sample dispersion is flowing, strobe light is irradiated at 1/30 second intervals to obtain an image of the particles flowing through the flow cell, so that each particle has a certain range parallel to the flow cell. Photographed as a two-dimensional image. From the area of the two-dimensional image of each particle, the diameter of a circle having the same area is calculated as the equivalent circle diameter.
In about 1 minute, the equivalent circle diameter of 1200 or more particles can be measured, and the number based on the equivalent circle diameter distribution and the ratio (number%) of particles having a prescribed equivalent circle diameter can be measured. As shown in Table 1, the results (frequency% and cumulative%) can be obtained by dividing the range of 0.06-400 μm into 226 channels (divided into 30 channels for one octave). In actual measurement, particles are measured in the range where the equivalent circle diameter is 0.60 μm or more and less than 159.21 μm.

<Evaluation of fine line reproducibility>
The developer was put into a modified machine in which a developing unit of a commercially available copying machine (Imagiono 271; manufactured by Ricoh) was improved, and running was performed using 6000 paper manufactured by Ricoh with a printing ratio of 7%. Compare the original 10th image and the 30,000th image thin line with the original, then magnify the image with an optical microscope at a magnification of 100x, and compare the line omission state with the stage sample. It was evaluated with.
(Evaluation criteria)
A: Level that can be used as a product B: Cannot be evaluated because it cannot be collected C: Level that cannot be used as a product

(Examples 2 to 5)
Using the same manufacturing apparatus as in Example 1, the toners of Examples 2 to 5 were obtained in the same manner as in Example 1 except that the position of the cylinder was arranged at the coordinate position (X, Y) shown in Table 1. It was.
Table 1 shows the evaluation results of the particle size distribution and fine line reproducibility of the obtained toners of Examples 2 to 5.
Each of the toners obtained in Examples 1 to 5 had high fine line reproducibility, and a toner that reproduced a clear image could be obtained.
As described above, by arranging the local turbulent flow generating means turbulent flow generating member at a predetermined position, extremely uniform particles can be produced even when the density of the discharge holes is high.

The value of [second peak (μm) / moderate diameter (μm)] in each example was 1.26 times.

1: toner production apparatus 2: droplet discharge means 6: toner component liquid supply port 7: toner component liquid flow path 8: toner component liquid discharge port 9: elastic plate 10: liquid column resonance droplet discharge unit 11: liquid column resonance Droplet discharge means 12: air flow path 13: raw material container 14: toner component liquid 15: liquid circulation pump 16: liquid supply pipe 17: liquid common supply path 18: liquid column resonance flow path 19: discharge hole 20: vibration generating means 21: Droplet 22: Liquid return pipe 23: Merged droplet 24: Nozzle angle 25: Turbulence generating member 60: Drying collecting means 61: Chamber 62: Toner collecting means 63: Toner storing means 64: Conveying air flow introduction Port 65: Conveyance airflow discharge port P1: Liquid pressure gauge P2: Chamber pressure gauge

Japanese Patent No. 3786034 Japanese Patent No. 3786035 JP-A-57-201248 JP 2006-293320 A

Claims (8)

Droplet discharge means for discharging a liquid containing the constituent components of particles as droplets;
An airflow generating means for generating an airflow transverse to the discharge direction of the droplets;
Droplet solidifying means for solidifying the droplet to form particles;
An apparatus for producing particles having
An apparatus for producing particles having a turbulent flow generating member on the upstream side of the airflow from the discharge hole.   The turbulent flow generation member is a columnar body having a circular or polygonal cross section, and is arranged such that the length direction of the columnar body is a direction perpendicular to the discharge direction and the airflow direction. Item 2. An apparatus for producing particles according to Item 1.   3. The particle manufacturing apparatus according to claim 2, wherein the turbulent flow generating member is disposed in the airflow direction on the upstream side of 0 mm or more and 5 mm or less from the discharge hole.   4. The particle manufacturing apparatus according to claim 2, wherein the turbulent flow generating member is disposed 1 mm or more and 5 mm or less away from the discharge hole in the droplet discharge direction. 5.   The apparatus for producing particles according to any one of claims 1 to 4, wherein the Reynolds number of the turbulent flow generation means is 300 or more.   A method for producing particles, comprising producing particles using the particle production apparatus according to claim 1.   An electrostatic image developing toner is produced using the particle production apparatus according to claim 1, wherein the electrostatic image developing toner is produced.   7. Particles produced by the method for producing particles according to claim 6, wherein the particles have a particle size distribution having a maximum peak at a diameter 1.26 times the mode diameter in the particle size distribution.