JP2008197196A - Production device and production method for toner particle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a production device for toner particles in which, for obtaining toner particles with small particle diameters and a sharp particle diameter distribution, the cooling capacity of a mechanical pulverizer is improved, and the adjustment operating time for the minimum intervals between a rotor and a stator can be reduced. <P>SOLUTION: The production device for toner particles includes a mechanical pulverizer for pulverizing toner particles containing a binding resin and a coloring agent, wherein the pulverizer includes: a rotor 314 fitted to a central rotary axis; a stator 310 arranged around the rotor keeping a fixed interval from the rotor surface; and a sheet for interval adjustment in the space between the stator and the mechanical pulverizer body, and wherein the product of the thickness A (mm) and Shore E hardness B in the sheet for interval adjustment A×B (mm) satisfies 1.5 mm≤A×B≤70.0 mm. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a toner manufacturing apparatus used in an image forming method such as an electrophotographic method, an electrostatic recording method, an electrostatic printing method, or a toner jet recording method.

  In an image forming method such as electrophotography, a toner for developing an electrostatic image is used. The toner production method is roughly classified into a pulverization method and a polymerization method, and a simple production method includes a pulverization method. As a general manufacturing method thereof, a binder resin for fixing to a transfer material, a colorant for giving a color as a toner is used, and a charge control agent for imparting electric charges to particles as necessary, After adding and mixing magnetic materials for imparting transportability etc. to the toner itself, additives such as a release agent and fluidity imparting agent, and melt-kneading and cooling and solidifying, the kneaded material is refined by a pulverizing means, If necessary, the toner is classified into a desired particle size distribution or further added with a fluidizing agent or the like to provide a toner for image formation. In the case of a toner used in the two-component development method, various magnetic carriers and the above toner are mixed and then used for image formation.

  Various pulverizers are used as the pulverizing means. From the viewpoint of energy saving in recent years, the mechanical pulverizing system shown in FIG. 1 is preferably used (see Patent Document 1).

  The mechanical pulverizer pulverizes by introducing a powder raw material into an annular space formed between a rotor 314 rotating at a high speed and a stator 310 arranged around the rotor. For this reason, to obtain toner particles having a small particle size and a sharp particle size distribution, it is necessary to increase the speed of the rotor and narrow the minimum distance between the rotor and the stator.

  However, increasing the speed of the rotor or reducing the minimum distance between the rotor and the stator increases the load during crushing, and the surface of the crushing surface (the outer peripheral surface of the rotor and the inner peripheral surface of the stator), particularly The wear on the inner peripheral surface of the stator is accelerated.

  If the load at the time of pulverization increases, the heat generated by pulverization also increases, so the cooling capacity of the mechanical pulverizer must be improved to prevent fusion.

  In addition, when the inner peripheral surface of the stator is worn, the stator must be replaced, and the minimum distance between the rotor and the stator needs to be readjusted.

  At this time, as an adhesive used in replacing the stator, a liquid thermosetting resin containing a metal or a metal compound having a high thermal conductivity and an adhesive that is cured by polymerization of two components are proposed. (See Patent Document 2).

  However, these adhesives require work to remove the adhesive adhered to the stator and mechanical crusher body when replacing the stator, and it takes time to cure, so workability is improved. It was bad. In addition, the adjustment of the minimum distance between the rotor and the stator depends on how the adhesive is applied and how it is applied, and depends largely on the operator's sense.

  In other words, in order to obtain toner particles having a small particle size and a sharp particle size distribution, the minimum distance between the rotor and the stator must be narrowed, so that adjustment is difficult and there is room for improvement in workability.

Japanese Patent Publication No. 3-15489 Japanese Patent Laid-Open No. 11-276916

  An object of the present invention is to obtain toner particles having a small particle size and a sharp particle size distribution, improving the cooling capacity of the mechanical pulverizer, and reducing the adjustment work time of the minimum distance between the rotor and the stator. The object is to provide an apparatus for producing particles.

That is, the present invention relates to a toner particle manufacturing apparatus including a mechanical pulverizer for pulverizing toner particles containing at least a binder resin and a colorant.
The pulverizer is a mechanical pulverizer including at least a rotor that is a rotating body attached to a central rotation shaft, and a stator that is arranged around the rotor while maintaining a certain distance from the rotor surface. Machine,
Between the stator and the mechanical pulverizer main body, at least a gap adjusting sheet is provided, and the product A · B (mm) of the thickness A (mm) and the Shore E hardness B of the gap adjusting sheet is 1. The present invention relates to an apparatus for producing toner particles, wherein 5 mm ≦ A · B ≦ 70.0 mm.

The present invention also relates to a method for producing toner particles using a mechanical pulverizer for pulverizing toner particles containing at least a binder resin and a colorant.
The mechanical pulverizer includes a rotor that is a rotating body attached to at least a central rotating shaft, and a stator that is disposed around the rotor while maintaining a certain distance from the surface of the rotor. Type crusher,
Between the stator and the mechanical pulverizer main body, at least a gap adjusting sheet is provided, and the product A · B (mm) of the thickness A (mm) and the Shore E hardness B of the gap adjusting sheet is 1. 5 mm ≦ A · B ≦ 70.0 mm,
Further, the present invention relates to a method for producing toner particles, which includes a jacket for cooling the inside of the machine and pulverizes the toner particles while passing a coolant through the jacket.

  In the mechanical pulverizer, a spacing adjusting sheet having thermal conductivity is used between the stator and the mechanical pulverizer body, and the product A · B of the thickness A (mm) and the Shore E hardness B is 1 By adjusting 0.5 mm ≦ A · B ≦ 70.0 mm and setting the thermal conductivity to 1.0 ≦ C ≦ 20.0, the adjustment work time of the minimum distance between the rotor and the stator can be shortened. Further, the mechanical pulverizer can have a high cooling capacity that has not been obtained conventionally.

  First, an outline of a pulverization method using a mechanical pulverizer used in the present invention will be described with reference to FIGS.

  FIG. 1 shows an example of a pulverization system incorporating a mechanical pulverizer used in the present invention, FIG. 2 shows a schematic cross-sectional view along the line DD ′ in FIG. 1, and FIG. The perspective view of the rotor which rotates at high speed is shown.

  Although FIG. 1 shows a schematic cross-sectional view of a horizontal general mechanical pulverizer, it may be a vertical type. Rotation in which a large number of grooves are provided on the surface of the casing 313, a jacket 316 that can pass cooling water in the casing 313, and a surface that rotates in the casing 313 and that is attached to the central rotating shaft 312 and that rotates at high speed. The stator 310, the stator 310 having a large number of grooves on the surface thereof arranged at regular intervals on the outer periphery of the rotor 314, the raw material inlet 311 for introducing the raw material to be processed, and the post-treatment And a raw material outlet 302 for discharging the powder.

  In the mechanical pulverizer configured as described above, when a predetermined amount of powder raw material is charged into the raw material charging port 311 of the mechanical pulverizer shown in FIG. It is introduced indoors. The impact generated between the rotor 314 provided with a large number of grooves on the surface rotating at a high speed in the grinding chamber and the stator 310 provided with a large number of grooves on the surface, and behind this It is pulverized instantaneously by a large number of ultra-high speed vortexes generated and high-frequency pressure vibrations generated thereby. Thereafter, the material passes through the material discharge port 302 and is discharged. The air carrying the particles (air) passes through the pulverization chamber and is discharged out of the apparatus system through the raw material discharge port 302, the pipe 219, the collecting cyclone 229, the bag filter 222, and the suction blower 224. The In the present invention, since the powder raw material is pulverized in this manner, a desired pulverization treatment can be easily performed without increasing the fine powder and coarse powder.

  Examples of such mechanical pulverizers include Inomizer (manufactured by Hosokawa Micron), Cryptoline (manufactured by Kawasaki Heavy Industries), Super Rotor (manufactured by Nisshin Engineering), Turbo Mill (manufactured by Turbo Industry), Tornado Mill (manufactured by Nikkiso Co., Ltd.) These can be used as they are or after being appropriately modified.

The present invention is a mechanical pulverizer for pulverizing toner particles containing at least a binder resin and a colorant, and the pulverizer includes at least a rotor that is a rotating body attached to a central rotation shaft; A mechanical crusher comprising the rotor surface and a stator disposed around the rotor while maintaining a constant interval;
As shown in FIG. 8, at least a gap adjusting sheet is provided between the stator and the mechanical pulverizer body, and a product A · B of a thickness A (mm) of the gap adjusting sheet and a Shore E hardness B is obtained. (Mm) is 1.5 mm ≦ A · B ≦ 70.0 mm.

  In the present invention, the distance adjusting sheet preferably has a product A · B (mm) with a thickness A (mm) of 1.5 mm ≦ A · B ≦ 70.0 mm.

  When the product A · B of the thickness A (mm) and Shore E hardness B of the spacing adjusting sheet is 1.5 mm ≦ A · B ≦ 70 mm, the adhesion between the stator and the mechanical grinder main body is improved. To do. For this reason, since the cooling of the jacket is easily transmitted to the stator, it is considered that the cooling capacity of the pulverizer is improved. Moreover, the adjustment becomes easy by selecting the sheet | seat of the thickness suitable for the minimum space | interval of a desired rotor and a stator.

  Further, one sheet having a desired thickness may be used as the gap adjusting sheet or a plurality of sheets may be used in a stacked manner. However, the most effective in the present invention is the gap adjusting sheet. This is when one sheet is used.

  When the product A · B of the thickness A (mm) and the Shore E hardness B of the gap adjusting sheet is smaller than 1.5 mm, the gap adjusting sheet becomes thin and soft. If the interval adjusting sheet is thickened, the thermal conductivity can be increased, but if it is thinned, there is a problem that the thermal conductivity is lowered. Further, when the gap adjusting sheet becomes soft, the adhesion between the stator and the mechanical grinder main body is improved, but it becomes difficult to keep the minimum gap between the rotor and the stator uniform.

  When A and B are larger than 70.0 mm, the spacing adjusting sheet becomes hard and the thickness increases. When the interval adjusting sheet becomes hard, the adhesion between the stator and the mechanical pulverizer main body is not improved, and the cooling of the jacket cannot be transmitted to the stator. Further, when the gap adjusting sheet is thick, it is difficult to reduce the minimum gap between the rotor and the stator.

  The distance adjusting sheet preferably has a thickness A (mm) of 0.2 mm <A <1.0 mm in consideration of a desired minimum distance and ease of narrowing. Further, from the viewpoint of adhesion between the stator and the mechanical pulverizer, the Shore E hardness B is preferably 0 <B <90.

  In the present invention, the thermal conductivity C (W / mK) of the gap adjusting sheet is preferably 1.0 W / mK ≦ C ≦ 20.0 W / mK. When the thermal conductivity C (W / mK) is 1.0 W / mK ≦ C ≦ 20.0 W / mK, heat generated by pulverization is easily transmitted from the stator to the jacket through which the cooling water can flow. Therefore, it is considered that the cooling capacity of the pulverizer is improved. When C is less than 1.0 W / mK, heat transfer is poor, heat generation due to pulverization cannot be suppressed, and fusion to the stator and rotor is caused. On the other hand, if C is greater than 20.0 W / mK, the spacing adjustment sheet becomes hard, the adhesion between the stator and the mechanical grinder main body is not improved, and the cooling capacity is not improved. In addition, it is difficult to adjust the minimum distance between the rotor and the stator.

  Examples of the spacing adjusting sheet include a heat dissipation sheet: PT-QS (manufactured by Polymertech) and PH-D (manufactured by OKI Electric Industry Co., Ltd.).

  As shown in FIGS. 4 and 5, the mechanical crusher used in the present invention is characterized in that the rotor and the stator are both a plurality of convex portions and concave portions formed between the convex portions and the convex portions. And at least the concave portion of the stator has a flat surface at the bottom.

  Since at least the concave portion of the stator has a flat surface at the bottom, the cross-sectional area of the concave portion, that is, the volume of the pulverization chamber can be increased, and the pressure loss at this portion can be reduced, so the concave portion is flat at the bottom. Compared with the case where there is no surface (FIGS. 6 and 7), more efficient grinding can be performed. The concave portion may have only a stator at the bottom (FIG. 4), or may have a flat surface at the bottom of the concave portions of the rotor and the stator (FIG. 5).

  Further, compared to the pulverized surface shape (FIGS. 6 and 7) when the concave portion does not have a flat surface at the bottom, the pulverized surface shape of the rotor and / or stator used in the present invention (FIGS. 4 and 5), Since the overall shape of the recess has a flat surface at the bottom, it becomes a trapezoidal or rectangular shape as a whole, so that the pressure loss at this portion can be reduced and the impact generated between the rotor and the stator. Becomes stronger and the grinding efficiency is improved. However, since the impact was strong as described above, there was a tendency that heat generation by pulverization was large.

  In the present invention, the contact area between the spacing adjusting sheet and the stator is larger in the stator in which the recess has a flat surface on the bottom than in the stator in which the recess does not have a flat surface on the bottom. For this reason, the heat generated by the pulverization is transmitted to the jacket through which the cooling water can flow through the flat surface, so that the cooling efficiency of the pulverizer is improved.

  In the present invention, as an in-machine cooling means of the mechanical pulverizer body, the mechanical pulverizer preferably has a structure having a jacket structure 316, and it is preferable to pass cooling water (preferably an antifreeze such as ethylene glycol). According to this method, the room temperature of the mechanical pulverizer can be controlled also by the water temperature and the amount of water passing through.

  The cooling water (preferably an antifreeze such as ethylene glycol) is supplied into the jacket from the cooling water supply port 317 and discharged from the cooling water discharge port 318. The cooling water temperature D (° C.) is preferably −25 ≦ D ≦ 5.

  Next, a procedure for manufacturing toner with the manufacturing apparatus of the present invention will be described.

  First, in the raw material mixing step, as a toner internal additive, at least a resin and a colorant are weighed and mixed in a predetermined amount and mixed. As a mixing apparatus, there are a double-con mixer, a V-type mixer, a drum-type mixer, a super mixer, a Henschel mixer, and a Nauta mixer.

  Further, the toner raw materials blended and mixed as described above are melt-kneaded to melt the resins and disperse the colorant and the like therein. In the melt-kneading step, a pressure kneader, a batch kneader such as a Banbury mixer, or a continuous kneader can be used. In recent years, single-screw or twin-screw extruders have become mainstream due to the advantage of continuous production, etc., KTK type twin screw extruder manufactured by Kobe Steel, TEM type twin screw extruder manufactured by Toshiba Machine Co., Ltd. -A twin screw extruder manufactured by CK Corporation and a co-kneader manufactured by Buss are generally used. Furthermore, the colored resin composition obtained by melt-kneading the toner raw material is rolled by a two-roll roll after melt-kneading, and then cooled through a cooling step of cooling by water cooling or the like.

  The cooled product of the colored resin composition obtained above is then pulverized to a desired particle size in a pulverization step. In the pulverization process, first, coarse crushing is performed with a crusher, a hammer mill, and a feather mill, and further, Inomizer (manufactured by Hosokawa Micron), Kryptron (manufactured by Kawasaki Heavy Industries), Super Rotor (manufactured by Nisshin Engineering), Turbo Mill (Turbo Industry) Finely pulverized by a mechanical pulverizer manufactured by Komatsu Ltd. In the pulverization step, the toner is pulverized to a predetermined toner particle size step by step.

  Next, raw materials for toner particles containing at least a binder resin and a colorant used in the present invention will be described.

  Examples of the toner binder resin that can be used in the present invention include the following. Polyester, polystyrene; polymer of styrene derivatives such as poly-p-chlorostyrene and polyvinyltoluene; styrene-p-chlorostyrene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-acrylic Acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, Styrene copolymers such as styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer; polyvinyl chloride, phenol resin, modified phenol resin, maleic resin, acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin; Polyester resins having as structural units monomers selected from aliphatic polyhydric alcohols, aliphatic dicarboxylic acids, aromatic dicarboxylic acids, aromatic dialcohols and diphenols; polyurethane resins, polyamide resins, polyvinyl butyral, terpenes Resin, coumarone indene resin, petroleum resin.

  The following are mentioned as a coloring agent used by this invention.

  Examples of the black colorant include carbon black; a magnetic material; a black colorant using a yellow colorant, a magenta colorant, and a cyan colorant.

  Examples of the color pigment for magenta toner include the following. C. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48, 49, 50, 51, 52, 53, 54, 55, 57, 58, 60, 63, 64, 68, 81, 83, 87, 88, 89, 90, 112, 114, 122, 123, 163, 202, 206, 207.209, 238; I. Pigment violet 19; C.I. I. Bat red 1, 2, 10, 13, 15, 23, 29, 35.

  As the colorant, a pigment may be used alone, but it is more preferable from the viewpoint of the image quality of a full-color image to improve the sharpness by using a dye and a pigment together.

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

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

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

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

  It is also preferable to use a pigment and a dye together.

  The amount of the colorant used is preferably 0.1 to 30 parts by weight, more preferably 0.5 to 20 parts by weight, and most preferably 3 to 15 parts by weight with respect to 100 parts by weight of the binder resin. is there.

  When the toner particles of the present invention are used as a magnetic toner, the magnetic material contained in the magnetic toner is not particularly limited as long as it is a commonly used magnetic material, but includes the following. Iron oxides including iron oxides such as magnetite, maghemite, ferrite, and other metal oxides; metals such as Fe, Co, Ni, or these metals and Al, Co, Cu, Pb, Mg, Ni, Sn , Zn, Sb, Be, Bi, Cd, Ca, Mn, Se, Ti, W, alloys with metals such as V, and mixtures thereof.

Specifically, the following are mentioned as a magnetic material. Iron trioxide (Fe ₃ O ₄ ), iron trioxide (γ-Fe ₂ O ₃ ), iron yttrium oxide (Y ₃ Fe ₅ O ₁₂ ), iron cadmium oxide (CdFe ₂ O ₄ ), iron gadolinium oxide (Gd) ₃ Fe ₅ O ₁₂ ), copper oxide copper (CuFe ₂ O ₄ ), lead iron oxide (PbFe ₁₂ O ₁₉ ), nickel oxide (NiFe ₂ O ₄ ), iron niobium oxide (NdFe ₂ O ₃ ), barium oxide (BaFe ₁₂ O ₁₉ ), iron oxide magnesium (MgFe ₂ O ₄ ), iron lanthanum oxide (LaFeO ₃ ), iron powder (Fe), cobalt powder (Co), nickel powder (Ni). The magnetic materials described above are used alone or in combination of two or more.

  Further, these magnetic materials are preferably contained in an amount of 60 to 200 parts by mass, and more preferably 80 to 150 parts by mass with respect to 100 parts by mass of the binder resin.

  The measurement method used in the present invention is shown below.

-Measurement of Shore E Hardness The Shore E hardness of the spacing adjusting sheet in the present invention was measured with a GS-721N type E durometer manufactured by Teclock Corporation in accordance with JIS K 6253-1997.

-Measurement of thermal conductivity (W / mK) The measurement of the thermal conductivity (W / mK) of the space adjusting sheet in the present invention can be measured using ChemthermQTM-D3 (manufactured by Kyoto Electronics Industry Co., Ltd.) It is preferable to measure by the probe method.

Measurement of particle size distribution The particle size distribution can be measured by various methods. In the present invention, a weight average particle size and a particle size distribution of the toner fine particles were obtained using a Coulter Multisizer (manufactured by Beckman Coulter, Inc.). As the electrolytic solution, a 1% NaCl aqueous solution is prepared using primary sodium chloride. For example, ISOTON R-II (manufactured by Coulter Scientific Japan) can be used. As a measurement method, about 2 ml of a surfactant, preferably alkylbenzene sulfonate, is added as a dispersant to about 100 ml of the electrolytic aqueous solution, and about 10 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is dispersed for about 1 minute with an ultrasonic disperser, and the volume distribution is measured by measuring the volume and number of toner fine particles of 2.00 μm or more using the 100 μm aperture as the aperture by the measuring device. And the number distribution are calculated, and the weight average particle diameter (the median value of each channel is used as a representative value for each channel) is obtained.

  As channels, 2.00 to 2.52 μm; 2.52 to 3.17 μm; 3.17 to 4.00 μm; 4.00 to 5.04 μm; 5.04 to 6.35 μm; 6.35 to 8. 00 μm; 8.00 to 10.08 μm; 10.08 to 12.70 μm; 12.70 to 16.00 μm; 16.00 to 20.20 μm; 20.20 to 25.40 μm; 25.40 to 32.00 μm; 13 channels of 32.00-40.30 μm are used.

-Molecular weight distribution by GPC measurement of binder resin The molecular weight of the chromatogram by gel permeation chromatography (GPC) is measured under the following conditions.

The column was stabilized in a heat chamber at 40 ° C., and tetrahydrofuran (THF) as a solvent was passed through the column at this temperature at a flow rate of 1 ml / min. About 50 to 200 μl of THF sample solution is injected and measured. In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value of a calibration curve prepared from several types of monodisperse polystyrene standard samples and the count number (retention time). Standard polystyrene samples for preparing a calibration curve include Tosoh Corporation or Pressure Chemical Co. The molecular weights manufactured are 6 × 10 ² , 2.1 × 10 ³ , 4 × 10 ³ , 1.75 × 10 ⁴ , 5.1 × 10 ⁴ , 1.1 × 10 ⁵ , 3.9 × 10 ⁵ , 8 ^{.6 × 10 5, 2 × 10} 6, used as a 4.48 × 10 ^6, it is appropriate to use at least about 10 standard polystyrene samples. An RI (refractive index) detector is used as the detector.

As a column, in order to accurately measure a molecular weight region of 10 ^{3 to} 2 × 10 ⁶ , it is preferable to combine a plurality of commercially available polystyrene gel columns, shodex GPC KF-801, 802, 803 manufactured by Showa Denko K.K. A combination of 804, 805, 806, and 807, and a combination of μ-styragel 500, 10 ³ , 10 ⁴ , and 10 ⁵ manufactured by Waters can be mentioned.

  Next, the present invention will be described more specifically with reference to examples and comparative examples of the present invention.

(Powder raw material production example)
-Binder resin (polyester resin): 100 parts by mass (molecular weight: Mp7200, Mn3000, Mw55600)
Magnetic iron oxide (spherical, particle size 0.2 μm): 90 parts by mass Azo-based iron complex compound: 2 parts by mass (made by Hodogaya Chemical Co., Ltd., trade name T-77)
Fischer-Tropsch wax: 3 parts by mass (manufactured by Nippon Seiwa Co., Ltd., trade name: FT-100, melting point: 98 ° C.)
After mixing the material of said prescription with a mixer, it knead | mixed with the biaxial kneader (PCM-30 type | mold, Ikegai make) set to 130 degreeC. The obtained kneaded product was cooled and coarsely pulverized to 2 mm or less with a hammer mill to obtain a powder raw material (coarse pulverized product) E which is a powder raw material for toner production.

  Further, the obtained powder raw material E was finely pulverized by a mechanical pulverizer (Turbo Mill T250-RS type manufactured by Turbo Kogyo Co., Ltd.).

  The mechanical pulverizer used in this example uses a gap adjusting sheet having different hardness, thickness, and thermal conductivity between the stator and the mechanical pulverizer body, and the minimum gap between the rotor and the stator is set. Set. The target weight average particle diameter (D4) was set to 5.3 μm ≦ D4 ≦ 5.7 μm, and the tip peripheral speed of the rotor was set so as to obtain this.

  The temperature of the air introduced into the mechanical pulverizer was set to −22 ° C., the pulverization supply amount was set to 20 kg / hr, and the powder raw material E was finely pulverized while flowing jacket cooling water at −15 ° C.

  Table 1 shows the time required for adjusting the rotor tip circumferential speed, the outlet temperature of the mechanical crusher, the minimum distance between the rotor and the stator, and the evaluation. Summarized.

The evaluation for the outlet temperature b [° C.] of the mechanical pulverizer was judged according to the following criteria.
A: b ≦ 40
B: 40 <b ≦ 45
C: 45 <b ≦ 50
D: 50 <b ≦ 55
E: 55 <b

Further, the evaluation of the time c [hr] required for adjusting the minimum distance between the rotor and the stator was determined according to the following criteria.
A: c ≦ 4
B: 4 <c ≦ 8
C: 8 <c

[Example 1]
In this example, a distance adjusting sheet having a thickness A of 0.7 mm, a Shore E hardness of B12, and a thermal conductivity of C 1.7 W / mK was used, and the minimum distance between the rotor and the stator was set to 0.6 mm. Further, the stator and the rotor shown in FIG. 4A were used, the circumferential speed of the rotor was set to 145 m / s, and the powder raw material E was finely pulverized under the above conditions.

  As a result, the obtained toner fine particles have a weight average particle size of 5.3 μm, 57.2% by number of particles having a particle size of 4.0 μm or less, and 0.5% by volume of particles having a particle size of 10.1 μm or more. And had a particle size distribution. The outlet temperature of the mechanical pulverizer during operation was 38 ° C.

  Furthermore, the time required for adjusting the minimum distance between the rotor and the stator was 4 hours.

[Example 2]
In this example, a distance adjusting sheet having a thickness A of 0.5 mm, a Shore E hardness B8, and a thermal conductivity C1.5 W / mK was used, and the minimum distance between the rotor and the stator was 1.0 mm. Further, the stator and rotor shown in FIG. 4A were used, the peripheral speed of the rotor was set to 150 m / s, and the powder raw material E was finely pulverized under the above conditions.

  As a result, the obtained toner fine particles have a weight average particle size of 5.5 μm, 56.4% by number of particles having a particle size of 4.0 μm or less, and 0.6% by volume of particles having a particle size of 10.1 μm or more. And had a particle size distribution. The outlet temperature of the mechanical pulverizer during operation was 36 ° C.

  Furthermore, the time required for adjusting the minimum distance between the rotor and the stator was 3 hr.

[Example 3]
In this example, a distance adjusting sheet having a thickness A of 0.8 mm, a Shore E hardness of B87, and a thermal conductivity of C4.5 W / mK was used, and the minimum distance between the rotor and the stator was set to 0.7 mm. Further, the stator and the rotor shown in FIG. 4A were used, the circumferential speed of the rotor was set to 145 m / s, and the powder raw material E was finely pulverized under the above conditions.

  As a result, the obtained toner fine particles have a weight average particle diameter of 5.4 μm, 57.0% by number of particles having a particle diameter of 4.0 μm or less, and 0.6% by volume of particles having a particle diameter of 10.1 μm or more. And had a particle size distribution. The outlet temperature of the mechanical pulverizer during operation was 45 ° C.

  Furthermore, the time required for adjusting the minimum distance between the rotor and the stator was 4 hours.

[Example 4]
In this example, a distance adjusting sheet having a thickness A of 0.4 mm, a Shore E hardness of B85, and a thermal conductivity of C4.5 W / mK was used, and the minimum distance between the rotor and the stator was set to 1.0 mm. Further, the stator and rotor shown in FIG. 4A were used, the peripheral speed of the rotor was set to 150 m / s, and the powder raw material E was finely pulverized under the above conditions.

  As a result, the obtained toner fine particles have a weight average particle size of 5.6 μm, 55.5% by number of particles having a particle size of 4.0 μm or less, and 0.7% by volume of particles having a particle size of 10.1 μm or more. And had a particle size distribution. The outlet temperature of the mechanical pulverizer during operation was 44 ° C.

  Furthermore, the time required for adjusting the minimum distance between the rotor and the stator was 3.5 hr.

[Example 5]
In this example, a distance adjusting sheet having a thickness A of 0.5 mm, a Shore E hardness B8, and a thermal conductivity C1.5 W / mK was used, and the minimum distance between the rotor and the stator was 1.0 mm. Further, the stator and the rotor shown in FIG. 6 were used, the circumferential speed of the rotor was set to 150 m / s, and the powder raw material E was finely pulverized under the above conditions.

  As a result, the obtained toner fine particles have a weight average particle size of 5.7 μm, 55.8% by number of particles having a particle size of 4.0 μm or less, and 0.4% by volume of particles having a particle size of 10.1 μm or more. And had a particle size distribution. The outlet temperature of the mechanical pulverizer during operation was 42 ° C.

  Furthermore, the time required for adjusting the minimum distance between the rotor and the stator was 3 hr.

[Comparative Example 1]
In this reference example, silicone resin KE-1223 (manufactured by Shin-Etsu Silicone) was used, and the minimum distance between the rotor and the stator was 1.0 mm. Further, the stator and rotor shown in FIG. 4A were used, the peripheral speed of the rotor was set to 150 m / s, and the powder raw material E was finely pulverized under the above conditions.

  As a result, the obtained toner fine particles have a weight average particle diameter of 5.7 μm, 56.3% by number of particles having a particle diameter of 4.0 μm or less, and 1.0% by volume of particles having a particle diameter of 10.1 μm or more. And had a particle size distribution. The outlet temperature of the mechanical pulverizer during operation was 47 ° C.

  Furthermore, the time required for adjusting the minimum distance between the rotor and the stator was 9 hr.

[Comparative Example 2]
In this comparative example, a copper plate having a thickness of 0.5 mm and a thermal conductivity of 403 W / mK was used, and the minimum distance between the rotor and the stator was 1.0 mm. Further, the stator and rotor shown in FIG. 4A were used, the peripheral speed of the rotor was set to 150 m / s, and the powder raw material E was finely pulverized under the above conditions.

  As a result, immediately after the operation, the outlet temperature of the mechanical pulverizer became 60 ° C. or higher, and fusion occurred, so that toner fine particles having a target particle size distribution could not be obtained.

  Furthermore, the time required for adjusting the minimum distance between the rotor and the stator was 8 hr.

[Comparative Example 3]
In this comparative example, an interval adjusting sheet having a thickness A of 0.8 mm, a Shore E hardness of B90, and a thermal conductivity of C 5.0 W / mK was used, and the minimum interval between the rotor and the stator was set to 0.7 mm. Further, the stator and the rotor shown in FIG. 4A were used, the circumferential speed of the rotor was set to 145 m / s, and the powder raw material E was finely pulverized under the above conditions.

  As a result, the obtained toner fine particles have a weight average particle size of 5.7 μm, 55.9% by number of particles having a particle size of 4.0 μm or less, and 1.5% by volume of particles having a particle size of 10.1 μm or more. And had a particle size distribution. The outlet temperature of the mechanical pulverizer during operation was 54 ° C.

  Further, the time required for adjusting the minimum distance between the rotor and the stator was 4.5 hours.

[Comparative Example 4]
In this comparative example, an interval adjusting sheet having a thickness A of 0.2 mm, a Shore E hardness of B5, and a thermal conductivity of C 0.3 W / mK was used, and the minimum interval between the rotor and the stator was set to 1.4 mm. Further, the stator and rotor shown in FIG. 4A were used, the peripheral speed of the rotor was set to 150 m / s, and the powder raw material E was finely pulverized under the above conditions.

  As a result, the obtained toner fine particles have a weight average particle size of 6.0 μm, 53.6% by number of particles having a particle size of 4.0 μm or less, and 1.9% by volume of particles having a particle size of 10.1 μm or more. The target particle size could not be obtained. Further, the outlet temperature of the mechanical pulverizer during operation was 57 ° C., and a fused material was generated during the operation.

  Further, the time required for adjusting the minimum distance between the rotor and the stator was 4.5 hours.

[Comparative Example 5]
In this comparative example, nothing was put between the mechanical grinder main body and the stator, and the minimum distance between the rotor and the stator was 1.5 mm. Further, the stator and rotor shown in FIG. 4A were used, the peripheral speed of the rotor was set to 150 m / s, and the powder raw material E was finely pulverized under the above conditions.

  As a result, immediately after the operation, the outlet temperature of the mechanical pulverizer became 60 ° C. or higher, and fusion occurred, so that toner fine particles having a target particle size distribution could not be obtained.

  Furthermore, the time required for adjusting the minimum distance between the rotor and the stator was 4 hours.

FIG. 3 is a schematic cross-sectional view of an example mechanical pulverizer used in the toner fine particle pulverization step of the present invention. It is a schematic sectional drawing in the D-D 'surface in FIG. It is a perspective view of the rotor shown in FIG. It is a schematic sectional drawing of the uneven | corrugated | grooved part vicinity of a rotor and a stator in the D-D 'surface in the mechanical grinder of this invention. It is a schematic sectional drawing of the uneven | corrugated | grooved part vicinity of the rotor and stator in D-D 'surface in other embodiment of the mechanical grinder of this invention. It is a schematic sectional drawing of the uneven | corrugated | grooved part vicinity of the rotor and stator in D-D 'surface in further another embodiment of the mechanical grinder of this invention. It is a schematic sectional drawing of the uneven | corrugated | grooved part vicinity of a rotor and a stator in the D-D 'surface in the conventional mechanical grinder. FIG. 2 is an example of a schematic cross-sectional view in which a gap adjusting sheet is provided between the stator and the pulverizer body on the D-D ′ plane in FIG. 1 of the present invention.

Explanation of symbols

212: Swirl chamber 219: Pipe 220: Distributor 222: Bag filter 224: Suction blower 229: Collection cyclone 301: Mechanical pulverizer 302: Powder discharge port 310: Stator 311: Powder input port 312: Rotation Shaft 313: Casing 314: Rotor 315: First metering feeder 316: Jacket 317: Cooling water supply port 318: Cooling water discharge port 320: Rear chambers 321 and 329: Waveform shapes 322 and 330 of the stator projections Flat surfaces 323 and 331 at the bottom of the concave part of the child concave part 324: Trapezoidal shape of the concave part of the rotor 325: Corrugated form of the concave and convex part of the stator 326 and 332: Trapezoidal forms of the concave part of the rotor 327 and 333: Rotor Flat surfaces 328, 334 at the bottom of the recesses: Waveform shapes 335, 337, 339 of the rotor projections: Waveforms 336, 33 of the projections and depressions of the stator , 340: Corrugated shape of the concavo-convex portion of the rotor 337: First slope 338 of the rotor: Second slope 339 of the rotor: First slope 340 of the stator 340: Second slope 340 of the stator: Rotor grinding blade 342 : Stator crushing blade 343: Space adjustment sheet

Claims (6)

In a toner particle manufacturing apparatus including a mechanical pulverizer for pulverizing toner particles containing at least a binder resin and a colorant,
The mechanical pulverizer includes a rotor that is a rotating body attached to at least a central rotating shaft, and a stator that is disposed around the rotor while maintaining a certain distance from the surface of the rotor. Type crusher,
Between the stator and the mechanical pulverizer main body, at least a gap adjusting sheet is provided, and the product A · B (mm) of the thickness A (mm) and the Shore E hardness B of the gap adjusting sheet is 1. An apparatus for producing toner particles, wherein 5 mm ≦ A · B ≦ 70.0 mm.   2. The toner particle manufacturing apparatus according to claim 1, wherein the interval adjusting sheet has a thermal conductivity C (W / mK) of 1.0 W / mK ≦ C ≦ 20.0 W / mK.   The rotor and the stator each have a plurality of corrugated convex portions and a concave portion formed between the convex portion and the convex portion, and at least the concave portion of the stator is a bottom portion. The toner particle manufacturing apparatus according to claim 1, wherein the toner particle manufacturing apparatus has a flat surface. In a method for producing toner particles using a mechanical pulverizer for pulverizing toner particles containing at least a binder resin and a colorant,
The mechanical pulverizer includes a rotor that is a rotating body attached to at least a central rotating shaft, and a stator that is disposed around the rotor while maintaining a certain distance from the surface of the rotor. Type crusher,
Between the stator and the mechanical pulverizer main body, at least a gap adjusting sheet is provided, and the product A · B (mm) of the thickness A (mm) and the Shore E hardness B of the gap adjusting sheet is 1. 5 mm ≦ A · B ≦ 70.0 mm,
Furthermore, a method for producing toner particles comprising a jacket for cooling inside the machine, wherein the toner particles are pulverized while passing a coolant through the jacket.   5. The toner particle manufacturing apparatus according to claim 4, wherein the gap adjusting sheet has a thermal conductivity C (W / mK) of 1.0 W / mK ≦ C ≦ 20.0 W / mK.   The rotor and the stator each have a plurality of corrugated convex portions and a concave portion formed between the convex portion and the convex portion, and at least the concave portion of the stator is a bottom portion. The toner particle manufacturing apparatus according to claim 4, wherein the toner particle manufacturing apparatus has a flat surface.

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