JP2006072120A - Method and apparatus for manufacturing toner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a toner containing a small amount of positively charged toner particles, having a sharp charge amount distribution and excellent in durability in printing on a large number of sheets, and to provide a manufacturing apparatus capable of manufacturing the toner in a high yield. <P>SOLUTION: In the method for manufacturing the toner, a spherical mixing tank is used in which stirring blades are attached, materials to be treated are discharged spirally upward along the inner wall of the tank by the stirring blades, the discharged materials to be treated are transferred to the tank top to reduce their kinetic energy, and the materials are resupplied to the stirring blades at the tank bottom. A support member is made to pierce through the tank wall of the mixing tank and a material flow regulating plate for changing the flow of the materials to be treated to the direction of a rotary drive shaft in the upper hemispherical part of the mixing tank is attached to the support member. Spherical resin particles having a shape factor (ML2/A) of 1.05-1.40, a shape factor (PM2/A) of 1.05-1.30 and a flow softening point (Tf1/2) of 100-130°C and containing at least a colorant and external additive particles are put in the mixing tank and mixed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a toner manufacturing method and toner manufacturing apparatus used in electrophotography, electrostatic recording, electrostatic printing, and the like.

  In the electrophotographic method, for example, after an electrophotographic toner is once attached to an image carrier such as a photoconductor on which an electrostatic latent image is formed, the image is transferred with or without an intermediate transfer medium in a transfer process. It is transferred to paper or the like, and is fixed by heat and pressure on the paper surface in the fixing step. As such an electrophotographic toner, a polymerization method toner, a pulverization method toner and a dissolution suspension toner are known. As the polymerization method toner, for example, a polymerization agent obtained by adding a release agent, a colorant, a charge control agent, a polymerization initiator, etc. in a polymerizable monomer and uniformly dissolving or dispersing it using a disperser. The monomer composition is charged into an aqueous phase containing a dispersion stabilizer, dispersed and polymerized to form toner mother particles. As a pulverized toner, for example, a release agent in a binder resin, After dispersing the colorant, charge control agent, etc., it is pulverized to a toner size by a fine pulverization means and classified into toner mother particles. Further, the dissolved suspended toner is made up of resin, colorant and other components in an organic solvent. The dissolved / dispersed solution is charged into the aqueous phase and dispersed, and then the organic solvent is removed from the obtained emulsion particles and dried to form toner mother particles. Each of the obtained toner base particles is mixed with external additive particles for the purpose of improving fluidity and stabilizing the chargeability to obtain an electrophotographic toner. As electrophotographic toners, there are one-component magnetic toners and one-component non-magnetic toners depending on the development method, and there are two-component toners composed of toner particles and carrier particles.

  In the mixing process of the toner base particles and the external additive in the production of such toner, a mixing treatment tank is used. The input weight of the external additive particles is about several percent with respect to the input weight of the toner base particles. In order to avoid adhesion in the mixing tank, the external additive particles are introduced after the toner base particles in the order of introduction into the mixing tank. As the mixing treatment tank, a Henschel mixer is frequently used. The Henschel mixer has a cylindrical mixing treatment tank 1 as shown in FIG. 4, and has a stirring blade that rotates at a high speed at the bottom of the mixing tank. Yes, the object to be processed is moved to the tank wall by the centrifugal force generated by the lower blade 11 rotating at high speed at the bottom of the tank, and the vertical tank wall of the cylinder is raised. Mixing is promoted by repeating the up-and-down motion of sliding down the inclined surface formed by the deposition of the workpiece itself by gravity and rising again due to centrifugal force given by the blade rotating at high speed. The In addition, the blades have a two-stage structure, and the upper blade 10 is rotated and the object to be processed is agitated to promote dispersion while sliding down the inclined surface due to the deposition of the object itself.

  In such a mixing treatment tank, since the moving direction of the object to be processed is suddenly changed at the rising portion of the cylindrical mixing treatment tank, heat is generated due to a change in the momentum thereof. Is welded inside the blade tip or inside the mixing treatment tank, resulting in a problem that the yield decreases. It is also known that a laminar flow plate for adjusting the flow of the mixture is provided in the upper part of the mixing tank (Patent Document 1), but the particles only slide off as they are in the slip portion due to gravity, and are less likely to rotate. The same part of the particles comes into contact with each other, and there is a problem in that it is difficult to obtain a desired dispersed adhesion state.

  Recently, in electrophotography, there has been a demand for low-temperature fixing of toner due to higher speed and energy saving, and internal dispersion in which release agent particles are dispersed in a binder resin for the purpose of low-temperature melting characteristics of toner particles. Type toners and toners in which the binder resin itself has melting characteristics suitable for low-temperature fixing have been developed. In the Henschel mixer, such a toner capable of fixing at a low temperature becomes more conspicuous in that the object to be processed is welded inside the stirring blade or the mixing processing tank and the yield is lowered. In addition, the toner has a small particle size of 3 to 10 μm for the purpose of high definition image and the toner has a spherical shape for the purpose of improving the transfer efficiency. For the purpose of uniform dispersion and adhesion, it is also known that the stirring blade (lower blade) in the Henschel mixer has high linearity (Patent Document 1). The problem still remains.

  Therefore, a method has been proposed in which the mixing tank is spherical and the toner base particles and external additive particles flow spirally upward at high speed along the tank inner wall, thereby enabling uniform external addition in a short time. (Patent Document 2, Patent Document 3). In this method, after the contents flow to the top of the treatment tank, the contents are re-supplied to the stirring blades at the bottom of the tank. Therefore, in the Henschel mixer, the up and down movement of the contents depending on gravity becomes more dynamic. The advantage is obtained that there is no need to stir the flow through the stage blades.

  However, although the toner base particles having a high sphericity are excellent in rolling properties, the surface area is relatively smaller than that of the irregular toner, and the amount of external additives that are liberated due to less surface irregularities. In many cases, it is difficult to uniformly deposit a predetermined amount of external additive particles, and thus the stirring speed must be increased. When the stirring speed in the tank is increased, welding occurs in the blade tip or inside the mixing treatment tank, resulting in a decrease in yield (recovered weight) or an increase in the amount of reversely charged toner. / M) cannot be narrowed.

In addition, when a spherical mixing layer is used and external additive particles are mixed with toner base particles having a high sphericity and high fluidity, or when a multistage treatment is performed, a fluidity improver is externally treated in the previous stage. In the case of performing the external addition process after the second stage in a more fluid state, even if the object to be processed is released spirally upward along the inner wall of the treatment tank in the spherical mixed treatment layer, mixing is performed. A fluidized layer of toner base particles is formed on the inner wall surface of the tank, and the external additive particles having a relatively small apparent specific gravity compared to the toner base particles may float on the fluidized bed or have a relative apparent specific gravity. Large external additive particles tend to remain on the inner wall surface of the mixing tank, and it takes a long time to uniformly disperse, and there is a distribution where the external additive particles adhere strongly and weakly. Problems such as increased ease of reverse charging toner, Can not narrow the charge distribution (Q / m), there is a problem that an adverse effect on the image formation.
JP-A-9-96923 Japanese Patent Laid-Open No. 8-173783 JP 2002-268277 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide a toner manufacturing method capable of manufacturing a toner having a small amount of positively charged toner, having a sharp charge amount distribution and excellent in durability of a large number of sheets in a high yield, and a manufacturing apparatus thereof. To do.

  The toner production method of the present invention is a toner production method using a spherical mixing treatment tank, wherein the spherical mixing treatment tank includes a horizontal disk-shaped tank bottom and a center of the horizontal disk-shaped tank bottom. A cylindrical member is attached to a rotary drive shaft that penetrates vertically, and a stirring blade that spirally discharges an object to be processed along the inner wall of the treatment tank, and vertically penetrates the top of the mixed treatment layer on an extension line of the rotary drive shaft. Is disposed so that the tip thereof is located in the mixing treatment tank, and the object to be treated released spirally upward by the rotation of the stirring blade is moved to the top of the tank to reduce its kinetic energy. Is re-supplied to the stirring blade at the bottom of the tank, and a support member that penetrates the tank wall of the mixing treatment tank is provided, and the flow direction of the object to be processed is rotated in the upper hemisphere of the mixing treatment tank. To be changed in the direction of the rotation axis It is set as the structure which attached the material flow control board, and a shape factor (ML2 / A) is 1.05-1.40 and a shape factor (PM2 / A) is 1.05-1. 30 and having a flow softening point (Tf1 / 2) of 100 to 130 ° C., spherical resin particles containing at least a colorant and external additive particles are added and mixed.

  The external additive particles are a mixture of hydrophobic silica fine particles having an average particle diameter of 5 nm to 50 nm and hydrophobic silica fine particles having an average particle diameter of 80 nm to 500 nm.

  The mixed toner is characterized in that the amount of free toner base particles measured by a particle analyzer is 40% by number or less.

  The toner production apparatus of the present invention is a toner production apparatus comprising a spherical mixing treatment tank for mixing and processing spherical resin particles containing at least a colorant and external additive particles as an object to be processed. A horizontal disk-shaped tank bottom, and a stirring blade that discharges the object to be processed spirally upward along the inner wall of the processing tank is attached to a rotary drive shaft that vertically penetrates the center of the horizontal disk-shaped tank bottom. The cylindrical member that vertically penetrates the top of the mixing treatment layer on the extension line of the rotation drive shaft is disposed so that the tip thereof is located in the mixing treatment tank, and is released spirally upward by the rotation of the stirring blade. The object to be processed is moved to the top of the tank to reduce its kinetic energy, and the object to be processed is re-supplied to the stirring blade at the bottom of the tank, and a support member penetrating the tank wall of the mixing process tank is provided. In the upper hemisphere of the mixing tank on the support member And a workpiece flow regulating plate for changing the flow direction of the workpiece to the rotation axis direction of the rotation drive shaft, and a shape factor (ML2 / ML) of the spherical resin particles in the workpiece. A) is 1.05-1.40, the shape factor (PM2 / A) is 1.05-1.30, and the flow softening point (Tf1 / 2) is 100-130 ° C.

  The surface of the workpiece flow regulating plate facing the workpiece is a fan-shaped surface, and the fan-shaped surface is in a direction in which the workpiece flows from a direction perpendicular to the direction in which the workpiece flows. It is attached to the support member so as to face each other in the range of 0 ° to 90 °, and the shape of the upper edge of the fan-shaped surface is made to correspond to the shape of the inner wall of the mixing treatment tank. The closest approach gap with the inner wall of the tank is 1 mm to 30 mm.

  The gap between the upper edge of the fan-shaped surface and the inner wall of the mixing tank is narrower than the edge of the upper edge of the rotation drive shaft and the inner wall of the mixing tank, and is closer to the rotation axis of the rotation shaft. The clearance gap between the upper end edge part of this and the inner wall of the mixing treatment tank is widened.

  The tip of the workpiece flow regulating plate, which is farther from the rotation axis direction of the rotation drive shaft, is higher than the attachment position of the stirring blade and is attached to a position lower than the tip of the cylindrical member in the tank. The flow of the object is changed in the direction of the rotation axis of the rotation drive shaft.

  The length of the upper edge of the fan-shaped surface of the workpiece flow regulating plate is set to 1/10 to 1/4 of the circumferential length when the inner surface of the processing tank is a sphere.

  The width of the fan-shaped surface of the workpiece flow regulating plate is set to 1/10 to 1/1 of the radius when the inner surface of the processing tank is a sphere.

  The toner production method and production apparatus of the present invention are suitable for external addition processing of toner base particles having a spherical shape and a low flow softening point, and have a small amount of free external additive and positively charged toner, and a sharp charge amount distribution. The toner has excellent durability, and the toner can be obtained in a high yield.

  The toner base particles used in the toner production method of the present invention are spherical resin particles containing at least a colorant, and the spherical resin particles have a shape factor (ML2 / A) of 1.05 to 1.40. Further, the shape factor (PM2 / A) is 1.05 to 1.30, and the flow softening point (Tf1 / 2) is 100 to 130 ° C.

  The shape factor (ML2 / A) and shape factor (PM2 / A) of the toner base particles are 500 toner images of 3 μm or more obtained by enlarging the toner base particles dispersed in water together with the dispersant 200 times with an optical microscope. Randomly sampled and obtained image information is introduced into the image analysis device (Luzex AP) manufactured by Nicole via the interface and analyzed, and the longest length of the real particle, the perimeter of the projected image of the real particle The projected area of each real particle is obtained and defined as a value obtained by calculation using the following equation.

ML2 / A = (π / 4) (longest length of real particle) ² / (projected area of real particle)
PM2 / A = (peripheral length of projected image of real particle) ² / (4π · projection area of real particle)
The shape factor (ML2 / A) indicates the degree of spherical shape of the toner base particles, and the shape factor (PM2 / A) indicates the degree of unevenness on the surface of the toner base particles. If the shape factor (ML2 / A) of the toner base particles exceeds 1.40 and the shape factor (PM2 / A) exceeds 1.30, the spherical shape approaches an indeterminate shape and the fluidity in the mixing treatment tank is poor. Even if the peripheral speed of the stirring blade is lowered, the yield is lowered, and the amount of positively charged toner is increased, and the charge amount distribution is expanded.

  Further, when the shape factor (ML2 / A) of the toner base particles is smaller than 1.05 and the shape factor (PM2 / A) is smaller than 1.05, the spherical shape approaches a true sphere and externally added to the toner base particles. Uniform adhesion of agent particles is difficult, so the peripheral speed of the stirring blade has to be increased, and toner mother particles are welded to the tip of the blade and the tank wall, resulting in a decrease in yield and free external addition. The amount of agent and the amount of positively charged toner also increase, and the charge amount distribution tends to widen.

  The spherical resin particles have a shape factor (ML2 / A) of 1.05-1.40, preferably 1.05-1.30, and a shape factor (PM2 / A) of 1.05-1. 30, preferably 1.05-1.20. Further, the value of the shape factor (ML2 / A) is preferably larger than the value of the shape factor (PM2 / A). By setting the toner shape to such a specific sphericity, it is possible to provide a toner manufacturing method with excellent toner yield, and a toner having a small amount of free external additive and positively charged toner and a narrow charge amount distribution. .

  The toner produced in the present invention is obtained by externally adding external additive particles to toner base particles to obtain a negatively chargeable toner. The toner base particles contain a binder resin and a colorant and are necessary. Accordingly, it contains internal additives such as a release agent, a dispersant, a charge control agent, and a magnetic agent.

  Examples of the binder resin include polystyrene resin, acrylate resin or methacrylate resin (hereinafter referred to as (meth) acrylate resin), styrene-acrylic resin, polyester resin, polyethylene resin, epoxy resin, silicone resin, polypropylene. Resins, fluororesins, polyamide resins, polyvinyl alcohol resins, polyurethane resins, polyvinyl butyral resins, and copolymers containing components of these resins are used.

  Such binder resins include those that are charged positively or weakly negatively as the resin itself, and examples thereof include polystyrene resins and styrene-acrylic resins. Examples of polystyrene resins include hydrogenated styrene resins, styrene-isobutylene copolymers, acrylonitrile-butadiene-styrene copolymers (ABS resins), acrylonitrile-styrene copolymers (AS resins), acrylonitrile-polyethylene chloride-styrene. Copolymer (ACS resin), styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-butadiene crosslinked polymer, styrene-butadiene-chlorinated paraffin copolymer, styrene-allyl alcohol copolymer, Examples thereof include styrene-butadiene rubber, styrene-maleic ester copolymer, styrene-isobutylene copolymer, and styrene-maleic anhydride copolymer.

  Examples of the styrene- (meth) acrylate resin copolymer include acrylate-styrene-acrylonitrile copolymer (ASA resin), styrene-diethylamino-ethyl methacrylate copolymer, styrene-methyl methacrylate copolymer, Styrene-n-butyl methacrylate copolymer, styrene-methyl methacrylate-n-butyl acrylate copolymer, styrene-methyl methacrylate-butyl allylate-N- (ethoxymethyl) acrylamide copolymer, styrene-glycidyl methacrylate Copolymer, styrene-butadiene-dimethylaminoethyl methacrylate copolymer, styrene-acrylic ester-maleic ester copolymer, styrene-methyl methacrylate-ethyl 2-acrylate Sil copolymer, styrene-n-butylarylate-ethyl glycol methacrylate copolymer, styrene-n-butyl methacrylate-acrylic acid copolymer, styrene-n-butyl methacrylate-maleic anhydride copolymer, styrene -Butyl acrylate-isobutyl maleic acid half ester-divinylbenzene copolymer, styrene-butadiene-acrylate copolymer, styrene-acrylate copolymer and the like. To these binder resins, a negative charge control agent is usually added to produce toner base particles having an appropriate negative charge amount.

  Examples of the resin that is negatively charged as the binder resin itself include a resin having a substituent such as a carboxyl group, a phenyl group, a thiophenyl group, or a sulfonic acid group in the side chain. These substituents are preferably in the form of metal salts. The metal salt is preferably a metal salt with zinc, magnesium, aluminum, sodium, calcium, chromium, iron, manganese, cobalt or the like. Alternatively, these substituents may be in the form of a salt with an organic base such as an ammonium ion, pyridinium ion, imidazolium ion or the like. As the negatively chargeable resin, a polyester resin is most preferably used.

  The polyester resin is obtained by polycondensation of a polyhydric alcohol and a polyvalent carboxylic acid or a derivative thereof, and has a carboxyl group in the side chain. As the polyhydric alcohol, dihydric alcohol, trihydric alcohol or tetrahydric or higher alcohol is used. Examples of the dihydric alcohol include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, 1,6-hexanediol, neopentyl glycol, diethylene glycol, Examples include dipropylene glycol, bisphenol A ethylene oxide adduct, and bisphenol A propylene oxide adduct. Examples of the trihydric alcohol include glycerol, trimethylolpropane, trimethylolethane, 1,2,4-butanetriol, 1,2,5-pentanetriol, 2-methylpropanetriol, 2-methyl-1,2,4- Examples include butanetriol and 1,3,5-trihydroxymethylbenzene. Examples of the tetravalent or higher alcohol include sorbitol, 1,2,3,6-hexanetetraol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, and the like. Among these, neopentyl glycol, totimethylol propane, bisphenol A ethylene oxide adduct, and bisphenol A propylene oxide adduct are preferably used, and these polyhydric alcohols are used alone or in combination.

  Examples of the polyvalent carboxylic acid include divalent carboxylic acids, trivalent or higher carboxylic acids, and derivatives thereof. Examples of the divalent carboxylic acid include malonic acid, succinic acid, glutaric acid, adipic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, phthalic acid, terephthalic acid, and isophthalic acid. These lower alkyl esters or acid anhydrides are used as derivatives of divalent carboxylic acids. As the lower alkyl ester, an alkyl ester having 1 to 12 carbon atoms, preferably a methyl ester or an ethyl ester is preferably used. Of these, phthalic acid, terephthalic acid, isophthalic acid, lower alkyl esters thereof, or anhydrides thereof, which are divalent carboxylic acids having an aromatic ring, are preferably used.

  Examples of trivalent or higher carboxylic acids include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1 , 2,4-Naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,5-hexatricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, tetra (methylenecarboxyl ) Methane, 1,2,7,8-octanetetracarboxylic acid, pyromellitic acid. Examples of these derivatives include lower alkyl esters or acid anhydrides of these carboxylic acids.

  There is no restriction | limiting in particular in the manufacturing method of a polyester resin, It manufactures by polycondensing a polyhydric carboxylic acid and a polyhydric alcohol by the method normally used by those skilled in the art. In the polycondensation, the molar ratio of the carboxyl group to the hydroxyl group (OH / COOH) is preferably between 0.8 and 1.4 as the reaction amount of the polyvalent carboxylic acid and the polyhydric alcohol. Moreover, it is preferable to adjust the acid value of the polyester resin obtained so that it may become 1-100 mgKOH / g. More preferably, it is 1-30. When the acid value is less than 1 mgKOH / g, the dispersibility of the internal additives such as the charge control agent, the release agent, and the colorant with respect to the binder resin decreases. When the acid value exceeds 100 mgKOH / g, the moisture resistance of the toner decreases.

  In particular, when a high level of offset resistance and transparency (fixed image smoothness) are desired, it is preferable to use a urethane-modified polyester resin as the polyester resin. The urethane-modified polyester resin is obtained by a reaction between a polyester resin and an isocyanate, and the isocyanate is 0.3 to 0.99 mole equivalent, preferably 0.5 to 0.95 mole equivalent per mole equivalent of hydroxyl group of the polyester resin. The reaction may be performed at a mixing ratio. If the molar ratio of isocyanate is less than 0.3, offset resistance may be lowered. If it is greater than 0.99, the viscosity rises remarkably and stirring may become difficult. Although there is no restriction | limiting in particular as isocyanate, Hexamethylene diisocyanate, isophorone diisocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, tetramethyl xylylene diisocyanate, etc. are used preferably.

  As the colorant, organic pigments, inorganic pigments, and dyes as shown below can be used. Among organic and inorganic pigments, carbon black, copper oxide, iron tetroxide, manganese dioxide, aniline black, activated carbon, etc. are used as the black pigment.

  Yellow pigments include chrome yellow, zinc yellow, cadmium yellow, yellow iron oxide, mineral fast yellow, nickel titanium yellow, navel yellow, naphthol yellow S, hansa yellow, benzidine yellow G, benzidine yellow GR, quinoline yellow lake, permanent yellow. NCG, tartrazine lake, etc. are used.

  As the orange pigment, red chrome yellow, molybdenum orange, permanent orange GTR, pyrazolone orange, Vulcan orange, indanthrene brilliant orange RK, benzidine orange G, indanthrene brilliant orange GKM and the like are used.

  Red pigments include Bengala, Cadmium Red, Red Plum, Mercury Sulfide, Cadmium, Permanent Red 4R, Risor Red, Pyrozolone Red, Watching Red, Calcium Salt, Lake Red D, Brilliant Carmine 6B, Eosin Lake, Rhodamine Lake B Alizarin lake, Brilliant Carmine 3B, etc. are used.

  As the purple pigment, manganese purple, fast violet B, methyl violet lake and the like are used. As the blue pigment, bitumen, cobalt blue, alkali blue lake, Victoria blue lake, phthalocyanine blue, metal-free phthalocyanine blue, phthalocyanine blue partially chlorinated product, first sky blue, indanthrene blue BC and the like are used.

  As the green pigment, chrome green, chromium oxide, pigment green B, malachite green lake, final yellow green G, or the like is used.

  As the white pigment, zinc white, titanium oxide, antimony white, zinc sulfide and the like are used.

  Examples of extender pigments include barite powder, barium carbonate, clay, silica, white carbon, talc, and alumina white.

  As the dye, basic dyes, acid dyes, disperse dyes, direct dyes, and the like are used. Examples of such dyes include nigrosine, methylene blue, rose bengal, quinoline yellow, and ultramarine blue.

  When the present invention is a translucent color toner, the following various pigments and dyes are used as the colorant.

  Examples of yellow pigments include CI10316 (Naphthol Yellow S), CI11710 (Hansa Yellow 10G), CI11660 (Hansa Yellow 5G), CI11670 (Hansa Yellow 3G), CI11680 (Hansa Yellow G), CI11730 (Hansa Yellow GR), CI11735 (Hansaero A), CI11740 (Hansaero NR), CI12710 (HansaEro R), CI12720 (Pigment Yellow L), CI21090 (Benzidine Eros G), CI21095 (Benzidine Eros G), CI21100 (Benzines Eros GR), CI20040 (Permanent Yellow NCG), CI21220 (Vulcan Fast Yellow 5), CI21135 (Vulcan Fast Yellow R), etc. are used.

  Red pigments include CI12055 (Starlin I), CI12075 (Permanent Orange), CI12175 (Risor Fast Orange 3GL), CI12305 (Permanent Orange GTR), CI11725 (Hansaero 3R), CI21165 (Vulcan Fast Orange GG) ), CI21110 (Benzidine Orange G), CI12120 (Permanent Red 4R), CI1270 (Paral Red), CI12085 (Fire Red), CI12315 (Brilliant Fast Scarlet), CI12310 (Permanent Red F2R), CI12335 ( Permanent Red F4R), CI12440 (Permanent Red FRL), CI12460 (Permanent Red FRLL), CI12420 (Permanent Red F4RH), CI12450 (Light Fast Red Toner B), CI12490 (Permanent Carmine FB), CI15850 ( Brilliantka Min 6B) and the like can be used.

  As the blue pigment, C.I.74100 (metal-free phthalocyanine blue), C.I.74160 (phthalocyanine blue), C.I.74180 (first sky blue), or the like is used.

  These colorants can be used alone or in combination of two or more, but it is desirable to use 1 to 20 parts by mass, preferably 2 to 10 parts by mass with respect to 100 parts by mass of the binder resin. When the amount is more than 20 parts by mass, the toner fixing property and transparency are deteriorated. On the other hand, when the amount is less than 1 part by mass, a desired image density may not be obtained.

  Release agents include paraffin wax, polyolefin wax, modified wax having aromatic group, hydrocarbon compound having alicyclic group, natural wax, long chain fatty acid having 12 or more carbon atoms or ester thereof, long chain fatty acid metal Salts (metal soaps), fatty acid amides, fatty acid bisamides and the like are used. Of the release agents, paraffin wax, polyolefin wax and metal soap are preferably used.

  Examples of the paraffin wax include paraffin wax (manufactured by Nippon Oil Co., Ltd. or Nippon Seiwa Co., Ltd.), micro wax (manufactured by Nippon Oil Co., Ltd.), and microcrystalline wax (manufactured by Nippon Seiwa Co., Ltd.). , Hard paraffin wax (manufactured by Nippon Seiwa Co., Ltd.), PE-130 (manufactured by Hoechst), Mitsui High Wax 110P (manufactured by Mitsui Petrochemical Co., Ltd.), Mitsui High Wax 220P (manufactured by Mitsui Petrochemical Co., Ltd.), Mitsui High Wax 660P (Mitsui Petrochemical Co., Ltd.), Mitsui High Wax 210P (Mitsui Petrochemical Co., Ltd.), Mitsui High Wax 320P (Mitsui Petrochemical Co., Ltd.), Mitsui High Wax 410P (Mitsui Petrochemical) ), Mitsui High Wax 420P (Mitsui Petrochemical Co., Ltd.), modified wax JC-1141 (Mitsui Petrochemical Co., Ltd.), modified wax JC-2130 (Mitsui Petrochemical Co., Ltd.), Modified wack JC-4020 (Mitsui Petrochemical Co., Ltd.), modified wax JC-1142 (Mitsui Petrochemical Co., Ltd.), modified wax JC-5020 (Mitsui Petrochemical Co., Ltd.), beeswax, carnauba wax, Montan A wax etc. can be mentioned.

  Examples of the polyolefin wax include low molecular weight polypropylene, low molecular weight polyethylene, oxidized polypropylene, oxidized polyethylene, and the like. Specific examples of polyolefin waxes include, for example, Hoechst Wax PE520, Hoechst Wax PE130, Hoechst Wax PE190 (manufactured by Hoechst), Mitsui High Wax 200, Mitsui High Wax 210, Mitsui High Wax 210M, Mitsui High Wax 220, Mitsui High Wax Non-oxidized polyethylene wax such as 220M (Mitsui Petrochemical Industries), Sun Wax 131-P, Sun Wax 151-P, Sun Wax 161-P (Sanyo Chemical Industries), Hoechst Wax PED121, Hoechst Wax PED153, Hoechst Wax PED521, Hoechst Wax PED522, Ceridust 3620, Ceridust VP130, Ceridust VP5905, Ceridust VP9615A, Ceridust TM9610F, Ceridust3715 (manufactured by Hoechst), Mitsui Oils & Chemicals 420M ) Oxidized polyethylene wax such as Sun Wax E-300, Sun Wax E-250P (Sanyo Kasei Kogyo Co., Ltd.), Hoechis t Non-oxidized polypropylene wax such as Wachs PP230 (Hoechst), Biscol 330-P, Biscol 550-P, Biscol 660P (Sanyo Chemical Industries), and Biscol TS-200 (Sanyo Chemical Industries, Ltd.) Oxidized polypropylene wax, such as

  As the fatty acid metal salt (metal soap), zinc stearate, calcium stearate, magnesium stearate, zinc oleate, zinc palmitate, magnesium palmitate and the like are preferably used.

  These release agents can be used alone or in combination. As the release agent, a compound having a low softening point (melting point) is preferable, and those having a softening point of 40 to 130 ° C, preferably 50 to 120 ° C are preferably used. The softening point is represented by an endothermic main peak value in a DSC endothermic curve measured by “DSC120” manufactured by Seiko Instruments Inc.

  As a dispersant, metal soap, polyethylene glycol or the like may be added.

  The charge control agent is used as necessary to control the chargeability of the toner base particles. When the degree of negative chargeability of the binder resin itself is low, or when the binder resin itself is positively charged, the entire toner base particles have a desired level of negative chargeability using a negative charge control agent. To have.

  Examples of the negative charge control agent include metal salts or metal complexes of salicylic acid derivatives, metal salts of benzylic acid derivatives, and phenylborate quaternary ammonium salts. As the metal salts of salicylic acid derivatives or benzylic acid derivatives, these zinc salts, nickel salts, copper salts, chromium salts and the like are preferably used. Examples of commercially available negative charge control agents include oil black (Color Index 26150), oil black BY (manufactured by Orient Chemical Co., Ltd.), Bontron S-22 (manufactured by Orient Chemical Co., Ltd.), and salicylic acid metal complex E. -81 (manufactured by Orient Chemical Co., Ltd.), thioindigo pigment, sulfonylamine derivative of copper phthalocyanine, Spiron Black TRH (manufactured by Hodogaya Chemical Co., Ltd.), Bontron S-34 (manufactured by Orient Chemical Co., Ltd.) ), Nigrosine SO (manufactured by Orient Chemical Co., Ltd.), Ceres Schwartz (R) G (manufactured by Farben Fabricen Bayer), Chromogen Schwarz ETOO (CINO.14645), Azo Oil Black (R) (National Aniline). Among these, salicylic acid metal complex E-81 is preferably used. These negative charge control agents can be used alone or in combination. The negative charge control agent is preferably blended in the binder resin so that the charge amount of the toner base particles is −5 to −60 μC / g. Therefore, although the addition amount with respect to binder resin is determined by the kind of binder resin to be used, generally it mix | blends in 0.1-5 mass parts with respect to 100 mass parts of binder resin.

  The positive charge control agent is internally added to the negative charge resin as necessary to adjust the negative charge amount of the toner base particles. A commercially available positive charge control agent is used as the positive charge control agent. For example, Nigrosine Base EX (manufactured by Orient Chemical Industries, Ltd.), quaternary ammonium salt P-51 (manufactured by Orient Chemical Industries, Ltd.), Nigrosine Bontron N-01 (manufactured by Orient Chemical Industries, Ltd.), Sudan Chief Schwarz BB (Solvent Black 3: Color Index 26150), Fettschwarz HBN (CINO.26150), Brilliant Spirits Schwarz TN (manufactured by Farben Fabricken Bayer), Zavon Schwartz X (manufactured by Farberge Hoechst). Of these, the quaternary ammonium salt P-51 is preferably used. In addition to the above, alkoxylated amines, alkylamides, molybdate chelate pigments and the like are also used as positive charge control agents. These positive charge control agents can be used alone or in combination.

Examples of magnetic agents include metal powders such as Fe, Co, Ni, Cr, Mn, and Zn, composite metal oxides such as Fe ₃ O ₄ , Fe ₂ O ₃ , Cr ₂ O ₃ , and various ferrites, manganese and acid. An alloy exhibiting ferromagnetism or the like may be added by heat treatment of the alloy or the like containing the alloy, and those previously treated with a coupling agent or the like may be used.

  The toner base particles may be any of toner base particles obtained by a pulverization method, a dissolution suspension method, or a polymerization method. As the pulverized toner, (1) a predetermined amount of additives such as a binder resin, a colorant, and a release agent are introduced into a mixer such as a Henschel mixer 20B (Mitsui Mining Co., Ltd.), and uniformly. Mix. (2) Next, the obtained mixture is charged into a twin-screw kneading extruder (PCM-30 manufactured by Ikekai Kasei Co., Ltd.) and uniformly melt-kneaded. Other melt kneading means include batch-types such as continuous kneaders such as “TEM-37” (Toshiba Machine Co., Ltd.), “KRC Kneader” (Kurimoto Iron Works Co., Ltd.), and heating / pressure kneaders. Examples thereof include a kneader. (3) The obtained melt-kneaded product is finely pulverized using a pulverizing means to obtain toner mother particles having a desired average particle diameter. For the pulverization, for example, a mechanical pulverizer turbo mill (Kawasaki Heavy Industries, Ltd.) is used in addition to the collision pulverization by jet air using a jet pulverizer 200AFG (Hosokawa Micron Corporation) or IDS-2 (Nippon Pneumatic Industry Co., Ltd.). ), Super Rotor (Nisshin Engineering Co., Ltd.) or the like. (4) After pulverization, the particle size of the obtained toner base particles is adjusted using wind power or rotor rotation. For example, when a wind classifier 100ATP (Hosokawa Micron Co., Ltd.), DSX-2 (Nippon Pneumatic Industry Co., Ltd.) or Elbow Jet (Nittetsu Mining Co., Ltd.) is used, a sharp particle size distribution is obtained. (5) In the pulverization process, the spheroidizing process of the pulverized toner uses a relatively round spherical pulverizing apparatus, for example, a turbo mill (manufactured by Kawasaki Heavy Industries) known as a mechanical pulverizer, or the particle size is adjusted. The toner is processed by a hot air spheronizer (manufactured by Nippon Pneumatic Industry), and its shape factor (ML2 / A) and shape factor (PM2 / A) are adjusted within the above-mentioned ranges.

  In addition, the dissolution suspension method toner is prepared by dissolving the above-described binder resin and the internal additive such as a colorant and a release agent in an organic solvent, and then dispersing and granulating it in a water phase together with a dispersant and an emulsifier. The toner base particles are obtained by separating and drying. Although the spherical toner base particles are obtained by the dissolution suspension method, the sphericity can be appropriately adjusted by heat-deforming at a temperature equal to or higher than the Tg temperature of the toner base particles.

  Next, the polymerization toner is obtained by suspension polymerization, emulsion polymerization, dispersion polymerization, or the like. In the suspension polymerization method, a monomer in which a polymerizable monomer, a color pigment, a release agent, and if necessary, a dye, a polymerization initiator, a crosslinking agent, a charge control agent, and other additives are dissolved or dispersed. The composition is added to an aqueous phase containing a suspension stabilizer (water-soluble polymer, poorly water-soluble inorganic substance) with stirring, granulated and polymerized to form colored toner base particles having a desired particle size. To do. In the materials used for the production of the polymerization toner, the same materials as those of the pulverized toner described above can be used for the colorant, the release agent, and the charge control agent.

  In the emulsion polymerization method, polymerization is performed by dispersing a monomer and a mold release agent, and if necessary, a polymerization initiator, an emulsifier (surfactant), etc. in water, followed by a colorant and a charge control agent in the aggregation process. By adding a coagulant (electrolyte) and the like, colored toner base particles having a desired particle size can be formed.

  As the polymerizable monomer component, known vinyl monomers can be used. For example, styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-methoxystyrene, p -Ethyl styrene, vinyl toluene, 2,4-dimethyl styrene, pn-butyl styrene, p-phenyl styrene, p-chloro styrene, divinyl benzene, methyl acrylate, ethyl acrylate, propyl acrylate, acrylic acid n- Butyl, isobutyl acrylate, n-octyl acrylate, dodecyl acrylate, hydroxyethyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, methyl methacrylate, ethyl methacrylate, methacryl Propyl acid, N-butyl tacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, hydroxyethyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, acrylic acid, methacrylic acid, maleic acid, fumaric acid , Cinnamic acid, ethylene glycol, propylene glycol, maleic anhydride, phthalic anhydride, ethylene, propylene, butylene, isobutylene, vinyl chloride, vinylidene chloride, vinyl bromide, vinyl fluoride, vinyl acetate, vinyl propyleneate, acrylonitrile, Examples include methacrylonitrile, vinyl methyl ether, vinyl ethyl ether, vinyl ketone, vinyl hexyl ketone, vinyl naphthalene and the like. Examples of fluorine-containing monomers include 2,2,2-trifluoroethyl acrylate, 2,2,3,3-tetrafluoropropyl acrylate, vinylidene fluoride, ethylene trifluoride, tetrafluoroethylene, and trifluoropropylene. Since fluorine atoms are effective for negative charge control, they can be used.

  Examples of the emulsifier (surfactant) include sodium dodecylbenzene sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, potassium stearate, calcium oleate, dodecyl ammonium chloride, dodecyl ammonium bromide. , Dodecyl trimethyl ammonium bromide, dodecyl pyridinium chloride, hexadecyl trimethyl ammonium bromide, dodecyl polyoxyethylene ether, hexadecyl polyoxyethylene ether, lauryl polyoxyethylene ether, sorbitan monooleate polyoxyethylene ether, and the like.

  Examples of the polymerization initiator include potassium persulfate, sodium persulfate, ammonium persulfate, hydrogen peroxide, 4,4′-azobiscyanovaleric acid, t-butyl hydroperoxide, benzoyl peroxide, 2,2′-azobis- There are isobutyronitrile and the like.

  Examples of the flocculant (electrolyte) include sodium chloride, potassium chloride, lithium chloride, magnesium chloride, calcium chloride, sodium sulfate, potassium sulfate, lithium sulfate, magnesium sulfate, calcium sulfate, zinc sulfate, aluminum sulfate, and iron sulfate. Can be mentioned.

  As a method for adjusting the sphericity of the polymerization toner, in the emulsion polymerization method, it can be appropriately adjusted by controlling the temperature and time during the aggregation process of the secondary particles. In addition, in the suspension polymerization method, spherical toner base particles are obtained, but the sphericity can be appropriately adjusted by heat-deforming at or above the Tg temperature of the toner base particles.

  The content of the release agent is 1 to 10 parts by weight, preferably 2 to 7 parts by weight with respect to 100 parts by weight of the binder resin from the viewpoint of grindability in the ground toner, and in the polymerization toner, Although it is 5 to 30 parts by mass, preferably 5 to 20 parts by mass, in the pulverized toner, the binder resin itself may have a low melting property. For example, Japanese Patent Application No. 2003-293707 filed earlier by the present applicant. Examples thereof include binder resins containing the crystalline polyester resin described in Japanese Patent Application Nos. 2003-293708 and 2003-293709.

  The mass average molecular weight of the binder resin is usually 2,000 to 30,000, preferably 4,000 to 25,000, and more preferably 6,000 to 20,000. If the molecular weight is less than 2,000, the flow softening point (Tf1 / 2) becomes too low, and the durability is lowered. In the case of a pulverized toner, the viscosity at the time of kneading is lowered, and the colorant is dispersed. There is a possibility that it cannot be performed sufficiently, and the saturation or transparency of the obtained toner may be lowered. When the molecular weight is larger than 30,000, the flow softening point (Tf1 / 2) becomes too high to be a toner that can be fixed at low temperature, and the viscosity is too high for the pulverized toner, and the colorant May not be sufficiently dispersed, and the saturation or transparency of the toner may be reduced. Moreover, there exists a possibility that a grindability may fall. A plurality of resins having a molecular weight within the above range may be mixed to form a binder resin. The molecular weight of the binder resin is measured by gel permeation chromatography (GPC).

  The toner base particles of the present invention have a flow softening point (Tf1 / 2) of the toner base particles of 100 to 130 ° C., preferably 100 to 120 ° C. in order to make the toner suitable for heat-pressure fixing at a low temperature during image formation. It is said. Further, the glass transition temperature (Tg) of the toner base particles is 50 to 100 ° C., preferably 60 to 90 ° C. Incidentally, the flow softening point (Tf1 / 2) in the toner obtained by adhering the external additive particles is 100 to 130 ° C., preferably 100 to 120 ° C., and the heat and pressure conditions (140 to 200 ° C.) in the fixing step. The toner can be fixed at a linear pressure of 0.04 to 0.1 kgf / mm), so-called “low-temperature fixable toner”.

  The flow softening point (Tf1 / 2) was measured by pressure-molding 1.0 g of a binder resin into a pellet and using “Flow Tester CFT-500D” manufactured by Shimadzu Corporation under the following conditions. To do. Temperature rising rate 5 ° C./min; cylinder pressure 2.0 MPa; die hole diameter 1.0 mm; die hole length 1.0 mm; Tm calculation method 1/2 method. Further, the glass transition temperature (Tg) of the binder resin is measured under the following conditions using 10 mg of the binder resin packed in an aluminum cell and using “DSC120” manufactured by Seiko Instruments Inc. Measurement temperature 0 to 200 ° C .; temperature increase rate 10 ° C./min: Read from DSC curve at the second temperature increase.

  The volume average particle diameter of the toner base particles is 9 μm or less, preferably 3.0 μm to 8 μm for both the pulverized toner and the polymerized toner. For toner particles larger than 9 μm, even if a latent image is formed at a high resolution of 1200 dpi or higher, the reproducibility of the resolution is lower than that of a small particle diameter toner. In addition, the use amount of the external additive increases in order to improve the fluidity, and as a result, the fixing performance tends to decrease, which is not preferable. The average particle diameter of the toner base particles and toner particles in the present invention is a value measured with a particle image analyzer (FPIA2100 manufactured by Sysmex).

  Next, examples of the inorganic external additive particles include hydrophobic additive-treated external additive particles having excellent environmental stability. Furthermore, for non-contact development, it is preferable to use external additive particles having different particle diameters. As the external additive particles having different particle diameters, external additive particles having an average particle diameter of 80 nm to 500 nm, preferably 90 nm to 300 nm, and external additive particles having an average particle diameter of 10 nm to 50 nm, preferably 10 nm to 40 nm are used. . The difference in average particle size between the external additive particles having a large particle size and the external additive particles having a small particle size is preferably 30 nm or more, and more preferably 50 nm or more. The particle diameter of the external additive particles is measured by electron microscopy. Hereinafter, the average particle diameter of the external additive particles is the primary average particle diameter.

  Examples of the external additive particles include negatively-charged silica fine particles and positively-charged silica fine particles for the purpose of charge adjustment. The small particle size silica particles are added for the purpose of improving the fluidity of the toner, The silica fine particles having a large particle diameter are added for the purpose of improving the charging stability and durability of the toner, or for making the toner suitable for non-contact development.

  The addition ratio of the large particle size silica to the small particle size silica is preferably 1: 4 to 2: 1 in terms of mass ratio in order to impart fluidity to the toner and to obtain long-term charge stability. . The addition amount of the silica fine particles may vary depending on the particle size distribution or fluidity of the toner base particles, or the particle size distribution of the external additive, the desired charge amount, etc. 0.5 to 2.0 parts by mass, preferably 0.5 to 1.5 parts by mass is added to 100 parts by mass of the base particles. As a large particle diameter silica, 0.1-2.0 mass parts, Preferably 0.2-1.0 mass parts is added. The large particle size silica and the small particle size silica are in a total amount of 0.5 to 3.0 parts by weight, preferably 0.7 to 2.2. 5 parts by weight are added.

  The silica fine particles are preferably hydrophobized. By making the surface of the silica fine particles hydrophobic, the fluidity and chargeability of the toner are further improved. Hydrophobization of silica fine particles can be achieved by using silane compounds such as aminosilane, hexamethyldisilazane and dimethyldichlorosilane; or dimethyl silicone, methylphenyl silicone, fluorine-modified silicone oil, alkyl-modified silicone oil, amino-modified silicone oil, epoxy-modified silicone oil, etc. This silicone oil is used, for example, by a method commonly used by those skilled in the art, such as a wet method or a dry method.

  Examples of the hydrophobic silica fine particles having a small particle diameter include commercially available RX200 (average particle diameter of 12 nm) and RX50 (40 nm) manufactured by Nippon Aerosil Co., Ltd. Examples of the large-sized hydrophobic silica fine particles include spherical amorphous silica (KE-E40, average particle size 180 nm), (KE-E30, average particle size 280 nm) manufactured by Nippon Shokubai Co., Ltd.

  Examples of the external additive particles include fine particles of titanium oxide having a relatively low electrical resistivity. Titanium oxide can take crystal forms such as rutile, anatase, and rutile-anatase. Any crystalline titanium oxide may be used, but the rutile-anatase type titanium oxide is easy to adjust the charge, and even if the number of printed sheets increases, the titanium oxide particles are not easily embedded in the toner base particles. It is preferably used in terms of Titanium oxide particles having a titanium oxide fine particle size or major axis size of 80 nm to 500 nm, preferably 90 nm to 300 nm, and 10 nm to 50 nm, preferably 10 nm to 40 nm, are used in combination.

  The addition ratio of titanium oxide having a large particle diameter and titanium oxide having a small particle diameter is preferably 3: 1 to 1: 3 by mass ratio. The addition amount of titanium oxide particles is 0.2 to 1.0 part by mass of titanium oxide having a small particle diameter with respect to 100 parts by mass of toner base particles. The titanium oxide having a large particle diameter is added in an amount of 0.2 to 1.0 part by mass, preferably 0.3 to 1.0 part by mass. The large particle size titanium oxide and the small particle size titanium oxide are added in a total amount of 0.4 to 2.0 parts by mass with respect to 100 parts by mass of the toner base particles in consideration of the mixing ratio.

The surface of the titanium oxide fine particles is hydrophobic in order to reduce the change in chargeability with respect to the change in the external environment of the toner (that is, maintain stable chargeability) and improve the fluidity of the toner. Is preferable. Hydrophobization of the titanium oxide fine particles is carried out by the same method as that of the negatively chargeable silica fine particles. Examples of the hydrophobic titanium oxide fine particles having a small particle diameter include STT-30S (average particle diameter 30 nm) manufactured by Titanium Industry Co., Ltd. Hydrophobic titanium oxide fine particles having a large particle size include ST110S (average particle size of 100 nm) manufactured by the company, ST121S manufactured by company (average particle size of 200 nm), ST120S manufactured by company (BET specific surface area of 3.0 m ² / g, average) Examples thereof include a particle size of 300 to 500 nm).

Inorganic fine particles other than titanium oxide fine particles can also be externally added for the purpose of controlling the chargeability and improving the fluidity. For example, inorganic fine particles include aluminum oxide, strontium oxide, tin oxide, zirconia, magnesium oxide, indium oxide and other metal oxide fine particles, silicon nitride and other nitride fine particles, silicon carbide and other carbide fine particles, calcium sulfate , Fine particles of metal salts such as barium sulfate and calcium carbonate, and inorganic fine particles such as a composite thereof. Metal oxide fine particles having an electrical resistivity of 10 ⁹ Ωcm or less and a relatively small electrical resistivity are preferably used. The size of the inorganic fine particles to be added is preferably a particle size of 10 to 30 nm. These inorganic fine particles are preferably subjected to a hydrophobic treatment on the surface for the purpose of stabilizing charging characteristics. For the hydrophobization treatment, the same method as any of the above-described hydrophobic methods for the negatively chargeable silica fine particles and the positively chargeable silica fine particles is employed.

  Further, after the toner base particles and the above-described inorganic external additive particles are mixed, particles composed of long-chain fatty acids or salts thereof may be mixed. As the long chain fatty acid, a saturated or unsaturated fatty acid having preferably 10 to 30 carbon atoms, more preferably 12 to 28 carbon atoms, and still more preferably 12 to 18 carbon atoms is used. The long-chain fatty acid may have a branch, but a linear saturated fatty acid such as stearic acid is preferably used. The long chain fatty acid is preferably used in the form of a salt, and more preferably in the form of a metal salt (so-called metal soap). Although there is no restriction | limiting in particular as a metal salt of a long chain fatty acid, For example, calcium salt, zinc salt, magnesium salt, aluminum salt, lithium salt etc. are mentioned. Examples of the metal soap include magnesium stearate, calcium stearate, zinc stearate and the like, and these fine particles are preferably used. The particles comprising a long-chain saturated fatty acid or a salt thereof may be used alone or in combination of two or more. The particulate long-chain fatty acid or salt thereof, particularly long-chain fatty acid metal salt (metal soap) particles have a volume average particle diameter or a major axis diameter of 0.1 to 10 μm, preferably 1 to 5 μm. If the average particle diameter or the major axis diameter is out of this range, the effect as a binder, lubricant, flow aid, or toner aggregation preventing effect tends to be insufficient.

  Long chain fatty acids or salts thereof, particularly metal soaps, preferably have a melting point of about 100 to 160 ° C. from the viewpoint of heat resistance and lubricity. When the melting point is lower than 100 ° C., the heat resistance of the toner is lowered, and the toner may aggregate when stored in a high temperature environment. If it is higher than 160 ° C., the lubricating action may be reduced. The particles comprising a long-chain saturated fatty acid or a salt thereof are added in an amount of 0.1 to 1.0 parts by weight, preferably 0.1 to 0.5 parts by weight, based on 100 parts by weight of the toner base particles. When the addition amount is less than 0.1 parts by mass, the effects as the binder, the aggregation preventing effect, the flow aid, the lubricant and the like may not be sufficiently exhibited. On the other hand, when the addition amount is more than 1.0 part by mass, the fluidity is inferior, the charge rising property is remarkably deteriorated, and noise such as fog may occur.

  Next, the toner manufacturing apparatus of the present invention will be described.

  In the mixing process of the toner base particles and the external additive particles, the spherical mixing processing tank shown in FIGS. 1 to 3 is used. FIG. 1 is a central sectional view, FIG. 2 is a plan view showing an example of a mixing blade, and FIG. 3 is a view showing a state in which the upper hemisphere portion of the mixed treatment layer is opened from the flange portion 8 and viewed from the inside. In the figure, 1 is a spherical mixing treatment tank, 2 is a horizontal disk-shaped tank bottom, 3 is a rotary drive shaft, 4 is a donut disk, 5 is a stirring blade, 6 is an air seal hole, 7 is a cylindrical member, 8 is A flange, 9 is a jacket, 11 is a stirring blade (turbine blade), 12 is a workpiece flow regulating plate, and 13 is a support member.

  As shown in FIGS. 1 and 2, the spherical mixing treatment tank 1 is provided with a horizontal disk-shaped tank bottom 2 and a turbine blade 11 having a conical section on a rotary drive shaft 3 passing vertically through the center of the tank bottom 2. In addition, a plurality of stirring blades 5 are respectively attached on the outer peripheral end portion. The turbine blade is a single-stage blade, and the shearing action by the blade is relatively small, and the mixing can proceed in a state where the dispersibility is reduced. In addition, a donut disk 4 for reinforcement is attached to the upper part of the stirring blade 5.

  At the top of the container 1, a cylindrical member 7 penetrating the top of the mixing treatment tank in the direction of the rotation axis of the rotary drive shaft 3 is arranged so that the tip of the tank is located in the upper hemisphere, and the seal air can be removed. To do. The upper hemisphere in the mixed treatment layer can be opened and closed from the flange 8 at the center, and the workpiece is introduced by opening the upper hemisphere. The thrown object to be processed is pressed against the inner wall surface of the processing tank 1 by the centrifugal force generated by the rotation of the stirring blade 5 and runs up spirally in the tank wall. At this time, the toner base particles entrain and adhere the external additive particles. The object to be processed that has risen up to the top collides with the cylindrical member 7 from which the seal air is released, lowers the kinetic energy, and the mixing and stirring of the toner base particles and the external additive particles proceed while falling on the turbine blade. The workpiece returned to the turbine blade also obtains a rotational force and again flows on the inner surface of the tank, and the external addition process proceeds. Further, the spherical mixing treatment tank is provided with a jacket 9 so that a heat medium can be flowed to heat or cool the object to be treated. A discharge port (not shown) is provided.

  Turbine blades 11 are fixed to the rotary drive shaft 3 through a seal air hole 6 so as to be rotatable, and are positioned between the outer periphery of the donut disk 4 and the inner wall of the tank as shown in FIGS. Are arranged as follows. Further, the lower edge of the stirring blade 5 is formed in an arc shape along the spherical inner wall of the processing tank 1 as shown in FIG. 1, and the object to be processed is rotated along the curved surface of the inner surface of the processing tank by rotating. It is set as the shape which can discharge | release spirally toward a processing tank top part. The seal air hole 6 is an air supply hole for preventing the object to be processed from entering the rotary drive shaft portion that becomes high temperature, and the supplied air is discharged from the cylindrical member 7.

  From the viewpoint of uniform processability of the object to be processed and the ability to discharge the supplied air, the length of the cylindrical member 7 inside the container is 1/20 or more of the height from the donut disk 4 inside the container, The length is preferably 1/3 or more, but it may be high enough that the tip of the cylindrical member does not come into contact with the powder surface when the workpiece is placed still. In addition, the cylindrical member 7 may have a structure other than the cylindrical shape so that the seal air can be removed. For example, the cylindrical member 7 may have a structure having a slit.

  The ratio between the diameter of the horizontal disk-shaped tank bottom 2 and the diameter of the treatment tank 1 is 0.25 to 0.80, and the ratio between the outer diameter of the donut-shaped disk 4 and the diameter of the horizontal tank bottom 2 is Is 0.50 to 1.20, and the ratio of the diameter of the turbine blade to the diameter of the treatment tank 1 is preferably 0.50 to 0.90. The ratio of the inner diameter to the outer diameter of the donut disk 4 is 0.5 to 0.95, preferably 0.7 to 0.8.

  Moreover, the preparation amount of the processing object to a spherical mixing processing tank is 0.1-0.9 by the ratio with respect to the volume of a processing tank, Preferably it is good to set it as 0.3-0.5.

  The spherical mixing treatment tank does not cause the object to be processed to rise abruptly like the Henschel mixer shown in FIG. 4, but the toner mother particles and the external additive particles as the object to be processed are arranged along the curved inner wall. It is possible to flow at a high speed, and the wall surface distance through which the material to be processed flows is long, and the toner base particles are easy to roll, enabling uniform external addition processing in a short time. Furthermore, after moving to the top of the mixing tank, the workpiece is reduced in kinetic energy, dropped, and re-supplied to the turbine blades at the bottom of the tank. The up-and-down movement becomes more dynamic. Moreover, it has the advantage that it is not necessary to provide an upper blade | wing. In addition, when the aggregation of the external additive particles is strong, it is possible to provide a convex portion in the tank to generate a turbulent flow and disintegrate.

  As shown in FIG. 1, the workpiece flow regulating plate 12 may be installed in the upper hemisphere via a support member 13 provided so as to penetrate the upper hemisphere tank wall in the mixing treatment tank. As a result, when the object to be processed forms a fluidized bed and comes to the upper hemisphere, a part of it collides to generate turbulent flow in the fluidized bed, and the external additive particles and fluidized bed in a state of floating from the fluidized bed This further improves the dispersive mixing, and enables uniform external addition in a short time. In consideration of the fact that in the spherical mixed treatment layer, the object to be treated flows on the inner surface of the tank, the object flow restriction plate is preferably installed in the upper hemisphere. In the lower hemisphere, the workpiece just released by the turbine blades is immediately turbulent, causing unevenness in the adhesion of external additive particles.

  The to-be-processed object flow restriction plate 12 is preferably attached to the support member 13 so that the to-be-processed object is in a direction in which the object to be processed is scraped in the direction of the rotation axis of the rotation drive shaft. In the direction opposite to the rotation axis direction of the rotation drive shaft, the flow of the fluidized bed is greatly disturbed, leading to a temperature rise of the object to be processed, and unevenness of the adhesion of the external additive particles occurs. As shown in FIG. 1, the workpiece flow regulating plate 12 has an upper edge a shape corresponding to the shape of the inner wall of the upper hemisphere in the mixing treatment tank, and the flow of the workpiece to the rotation axis direction of the rotary drive shaft 3 (see FIG. 1). It is good to make it the shape which provided the fan-shaped surface A restrict | limited to the dotted line direction in 1). In addition, as shown in FIG. 3, the mounting angle is a direction in which the fan-shaped surface A is perpendicularly opposed to the direction in which the workpiece discharged spirally upward along the inner wall of the processing tank flows (in FIG. 3). When the direction of the dotted line) is 0 °, it is opposed to the direction in which the workpiece flows in the angle range of θ, and the flow direction of the workpiece is the rotational axis direction of the rotary drive shaft 3, It is good to attach so that it may regulate in the downward direction of a member. If the flow direction of the object to be processed is directed to the cylindrical member, the object to be processed accumulates on the cylindrical member, which is not preferable. The angle θ may be greater than 0 ° and 90 ° or less, and preferably 20 to 60 °. If θ is out of the range, the vertical movement of the workpiece will be hindered, the flow of the fluidized bed will be greatly disturbed, the temperature of the workpiece will rise, and unevenness of the external additive particles will occur. Therefore, it is not preferable.

  Moreover, the to-be-processed substance flow control board is good to provide a tank inner surface and a clearance gap. If it is in contact with the inner wall surface, a portion that does not flow is generated, and a fixed layer is formed in the portion, and unevenness occurs in the degree of adhesion of the external additive particles. Therefore, the distance of the closest clearance between the upper edge a of the fan-shaped surface A and the inner wall b of the upper hemisphere in the mixing treatment tank is 1 mm to 30 mm, preferably 2 mm to 15 mm. If it exceeds 30 mm, the effect of turbulent flow cannot be obtained sufficiently.

  Further, since the layer thickness of the object to be processed, which is scraped in the direction of the rotation axis by the object to be processed flow regulation plate, increases, it is necessary to widen the gap with the inner wall surface of the tank. Therefore, the gap (interval) between the upper edge portion a ′ closer to the rotational axis direction of the rotational drive shaft on the fan-shaped surface A and the upper hemisphere inner wall b ′ may be widened, and at least 1.0 mm or more, preferably 1.5 mm or more. Good.

Further, the arc length (L ₁ ) of the upper edge a of the fan-shaped surface A in the workpiece flow regulating plate 12 is different depending on the mounting angle of the workpiece flow regulating plate, but the inner surface of the treatment tank is a sphere. In this case, the circumference may be 1/10 to 1/4, preferably 1/8 to 1/5. If it is less than 1/10, the effect of generating turbulent flow is small, and if it exceeds 1/4, turbulent flow becomes too large.

Further, the width (L ₂ ) of the fan-shaped surface A in the processing object flow regulating plate is preferably equal to or greater than the thickness of the fluidized layer on the inner wall surface formed by centrifugal force of the processing object, particularly the toner base particles. The radius is 1/10 to 1/1, preferably 1/8 to 1/2 of the radius when the inner surface is a sphere. If the amount is less than 1/10, the treatment flow regulation plate is buried in the fluidized bed when the amount of treatment is large, and the effect of generating turbulence cannot be obtained. On the other hand, if the radius is larger than the radius, the inside of the regulating plate will be opposed to the direction of the fluidized bed. Arise.

  In addition, the tip end portion (a ″) of the workpiece flow regulating plate is naturally positioned higher than the turbine blade mounting position, but is positioned lower than the tip end of the cylindrical member for removing the seal air. If the cylindrical member is longer than the tip of the workpiece flow regulating plate, the workpiece to be scraped in the rotation axis direction by the workpiece flow regulating plate collides with the cylindrical member surface. There is a risk of adhering and reducing the recovery rate.

  Further, the shape of the support member 13 may be a streamline shape to prevent the workpiece from sticking, and its sharp tip may be oriented in the flow direction of the workpiece. Is preferably set so that the fan-shaped surface of the workpiece flow restricting plate has the above-described arrangement. In addition, as for the to-be-processed object flow control board 12, a SUS304 board is illustrated as a material, for example, and thickness is 2 mm-10 mm.

  By providing the workpiece flow regulating plate 12, the flow of resin particles having high fluidity can be disturbed and uniformly dispersed and mixed with external additive particles in a shorter time, so that the charge amount distribution can be made uniform. In addition, the amount (number%) of free external additive particles can be reduced, and the amount of toner having a reverse polarity can be reduced. Further, the amount (number%) of free toner base particles can be reduced, the amount of resin particles adhering to the curved portion (R portion) and the turbine blades can be reduced, and the yield can be improved.

  The workpiece flow regulating plate can be attached to the cylindrical member 7 with an attachment jig. However, if the attachment jig is long, the workpiece is prevented from falling, disturbing the vertical movement, Since the toner mother particles adhere to the tool and the recovery rate is lowered, there is a problem that the attachment position of the processing object flow restriction plate is limited to the vicinity of the top of the processing tank.

  When mixing various external additive particles to the toner base particles, the processing conditions such as the order of introduction into the spherical mixing tank, the stirring speed, the time, etc. are such that the adhesion of the external additive particles to the toner base particles is uniform. It may be adjusted as appropriate, and when a plurality of types of external additive particles are added, they may be externally added in multiple stages. In the multi-stage external addition treatment, a plurality of external additive particles are mixed separately, and even if they are of the same type, they are mixed in a plurality of times.

  To produce toner using a spherical mixing tank, the mixing process becomes insufficient if the mixing process time is short, and if the mixing process time is long, the object to be processed adheres to the tank wall or turbine blades. Since it is generated and the yield is lowered, the treatment time for one time needs to be within the range of 0.5 to 10 minutes, preferably 1 to 5 minutes. In addition, in order to avoid a temperature rise, the process in each step may be divided into several times and mixed. In addition, if the stirring speed is low, the mixing process becomes insufficient, and if the stirring speed is high, the object to be processed is welded to the tank wall, turbine blades, etc., and the yield is reduced. The peripheral speed (π × outermost diameter of blade × rotational speed / hour) of the turbine blade in the range of 10 m / s to 100 m / s.

  The toner thus obtained has a volume average particle size of 3 to 9 μm, preferably 3 to 8 μm. Even if toner particles larger than 9 μm form a latent image at a high resolution of 1200 dpi or higher, the reproducibility of the resolution is lower than that of a small particle diameter toner. In addition to the decrease, the amount of the external additive used for increasing the fluidity increases, and as a result, the fixing performance tends to decrease. The volume average particle diameter of the toner is a value measured by a flow type particle image analyzer (FPIA2100 manufactured by Sysmex).

  The amount (number%) of free toner base particles and free inorganic external additive particles is measured using a particle analyzer (“PT1000” manufactured by Yokogawa Electric Corporation) with the total number of measurements being around 5000. And the number of detected elements such as Si (inorganic external additive particles released from the toner mother particles) that are not synchronized with the carbon atoms (toner mother particles) of the toner particles introduced into the plasma flame with He gas is measured. The liberation rate (number%) is calculated by the following formula. The state of adhering to the toner base particles is detected as the synchronous number.

Free silica (number%)
= Number of asynchronous Si / (number of asynchronous Si + number of synchronous Si) × 100
Free toner base particles (number%)
= Number of asynchronous C / (number of asynchronous C + number of synchronous C) × 100
According to the method for producing a toner of the present invention, in the obtained toner, the liberation rate of inorganic external additive particles can be 1 to 10% by number, preferably 1 to 5% by number, and the amount of positively charged toner is small. In addition, the toner can be a toner having a uniform charge distribution, and has a high OD value when applied to non-contact development, and excellent durability of a large number of sheets. When the liberation rate of inorganic external additive particles is more than 10% by number, the amount of positively charged toner increases, the charge distribution is not sharp, the fog is large, and the OD value when applied to non-contact development is low. Also, the durability of a large number of sheets is inferior.

  Further, when the amount of the free toner base particles is 15 to 40% by number, the production method can be made with a high yield with less fusion to the apparatus.

  The toner of the present invention has a shape factor (ML2 / A) measured in the same manner as described above of 1.05-1.40, preferably 1.05-1.30, and a shape factor (PM2 / A). 1.05-1.30, preferably 1.05-1.20. Further, the value of the shape factor (ML2 / A) is preferably larger than the value of the shape factor (PM2 / A), and a toner having excellent transferability can be obtained. The toner of the present invention has a flow softening point (Tf1 / 2) of 100 to 130 ° C, preferably 100 to 120 ° C, and a glass transition temperature (Tg) of 50 to 100 ° C, preferably 60 to 90 ° C. In other words, it is a so-called “low temperature fixable toner” that can be fixed under hot pressure conditions (140 to 200 ° C., linear pressure 0.04 to 0.1 kgf / mm) in the fixing step.

  The average charge amount of the toner particles to which the external additive particles are attached is preferably -5 to -30 μC / g. If the charge amount is smaller than this range, toner leakage from the developing device becomes severe. If the charge amount is larger than this range, it is necessary to apply an excessive developing bias in order to obtain a sufficient image density. Such problems arise.

  The toner produced in the present invention can be applied to any one of image forming apparatuses using a one-component or two-component toner described in detail in JP-A-2002-202622. The toner can be applied to both an image forming apparatus and a non-contact developing type image forming apparatus, but can be a toner suitable for application to an image forming apparatus having a non-contact developing type.

  A monomer mixture consisting of 80 parts by mass of styrene monomer, 20 parts by mass of butyl acrylate, and 5 parts by mass of acrylic acid, 105 parts by mass of water, 1 part by mass of nonionic emulsifier (Emulgen 950 manufactured by Daiichi Kogyo Seiyaku), anionic emulsifier (first It was added to an aqueous solution mixture of 1.5 parts by mass of Neogen R) manufactured by Kogyo Seiyaku Co., Ltd. and 0.55 parts by mass of potassium persulfate, and polymerization was carried out at 70 ° C. for 8 hours while stirring in a nitrogen stream. After the polymerization reaction, the mixture was cooled to obtain a milky white resin emulsion having a particle size of 0.25 μm.

  Next, 200 parts by mass of this resin emulsion, 20 parts by mass of polyethylene wax emulsion (manufactured by Sanyo Chemical Industries, Ltd.) and 7 parts by mass of phthalocyanine blue were used as surfactants, and 0.2 part by mass of sodium dodecylbenzenesulfonate was included. Disperse in 2 liters of water, add diethylamine to adjust pH to 5.5, add 0.3 parts by weight of aluminum sulfate as an electrolyte while stirring, then stir at high speed with a stirrer (TK homomixer) Dispersion was performed.

  Further, 40 parts by mass of a styrene monomer, 10 parts by mass of butyl acrylate, and 5 parts by mass of zinc salicylate were added together with 40 parts by mass of water. And polymerized for 5 hours to grow particles. In order to increase the bond strength of the associated particles after the polymerization was stopped, the temperature was raised to 95 ° C. while maintaining the pH at 5 or higher and held for 5 hours. Thereafter, the obtained particles were washed with water, and further vacuum dried at 45 ° C. for 10 hours while adding 0.5% by mass of silica fine particles (primary particle size 40 nm) to obtain toner mother particles.

  The average particle diameter of the toner base particles was 7.1 μm, the flow softening point (Tf1 / 2) was 112.6 ° C., ML2 / A was 1.10, and PM2 / A was 1.06.

  1 kg of toner mother particles (made by Mitsui Mining Co., Ltd., Q type mixer 20L type, stirring blades are turbine blades, and the inner wall is 1/16 of the circumference from the top of the processing tank) To the support member attached to the position, the work flow restricting plate is attached to a position where the total length of the restricting plate is divided by 1: 4 so that the length of the end surface on the top side of the processing tank from the support member is reduced. After passing water at 25 ° C. at a rate of 35 liters / min, the rotating shaft is cooled with water, and loaded into sealant air to prevent the entry of the object to be processed), silica fine particles {RX200 made by Nippon Aerosil Co., Ltd. ( An average particle size of 12 nm) and silica fine particles (A mixture of 1: 1 (mass ratio) RX50 (average particle size of 40 nm) manufactured by Nippon Aerosil Co., Ltd.) at a ratio of 1% by mass with respect to the toner base particles are as follows. so It was added processing.

  The spherical mixing tank has an internal volume of 20 liters, the length of the cylindrical member 7 inside the container is 1/11 of the height from the donut disk 4 inside the container, and the diameter of the tank bottom 2 and the processing tank The ratio of the diameter of 1 to 0.57, the ratio of the outer diameter of the donut disk 4 to the diameter of the horizontal tank bottom 2 is 1.10, the ratio of the diameter of the turbine blade 11 to the diameter of the treatment tank 1 Is 0.75, and the ratio of the inner diameter to the outer diameter of the donut disk 4 is 0.73.

Further, the ratio of the width (L ₂ ) of the workpiece flow regulating plate to the radius on the inner wall surface side of the tank is 0.2, the ratio of the length (L ₁ ) to the peripheral length on the inner wall surface side is 0.13, θ = 60 °, the distance of the shortest gap between the upper end of the fan-shaped surface of the workpiece flow regulating plate and the inner wall of the vessel is 3.0 mm, from the vessel bottom of the tip portion farther from the rotational axis direction in the workpiece flow regulating plate The difference between the height of the cylindrical member and the height of the cylindrical member tip from the tank bottom (positive when the tip of the workpiece flow regulating plate is low) is 30 mm, and the workpiece flow regulating plate closer to the rotating shaft And the inner wall of the tank (gap) was 9.5 mm.

The spherical mixing treatment tank was mixed with a seal air amount of 1.0 Nm ³ / h, a turbine blade peripheral speed of 51 m / s, and a mixing time of 2 minutes. The peripheral speed of the turbine blade was calculated from the outermost diameter of the blade and the rotational speed.

  The ratio (yield) of the recovered weight to the input weight of the object to be processed was 97.5%. Further, the number free rate of silica fine particles in the obtained toner was 0.9% by number, and the amount of free toner base particles was 21.5% by number.

  Next, the obtained toner was loaded into a toner cartridge of a color printer (“LP9000C” manufactured by Seiko Epson Corporation), and solid printing was performed. After printing, the toner cartridge was taken out, and the toner charge amount distribution on the developing roller was measured. For the measurement, a charge amount distribution measuring device (“E-SPART III” manufactured by Hosokawa Micron Corporation) was used, and the number of measurement was 3000. The positively charged toner amount was 6.6% by number, and the standard deviation (μC / g) of the ratio (Q / m) between the charge amount and the mass determined from the particle diameter was 18.5.

  The yield was high, the amount of free external additive and the amount of positively charged toner was small, and a uniform external addition process with a narrow charge amount distribution was achieved.

  In the production of the toner base particles of Example 1, the wax emulsion was 15 parts by mass, the temperature and time were adjusted in the secondary particle aggregation process, the average particle size was 7.5 μm, and the flow softening point (Tf1 / 2) was 120. The toner base particles were 0.4 ° C., ML2 / A was 1.25, and PM2 / A was 1.08.

  25.0 kg of the obtained toner mother particles are attached to a spherical mixing tank (Mitsui Mine Co., Ltd., Q-type 150L, the stirring blade is a turbine blade, attached to the inner wall position that is 1/17 of the circumference from the top of the processing tank. The workpiece flow restriction plate is attached to the support member at a position where the full length of the restriction plate is divided 1: 5 so that the length of the end surface on the processing tank top side from the support member is reduced, and the jacket has a water temperature of 21 ° C. After passing water at a rate of 70 liters / min, the rotating shaft is cooled with water, and loaded with seal air to prevent the intrusion of the object to be processed), silica fine particles {RX200 manufactured by Nippon Aerosil Co., Ltd. (average particle size 12 nm) And silica fine particles {A mixture of 1: 1 (mass ratio) RX50 (average particle diameter 40 nm) manufactured by Nippon Aerosil Co., Ltd. at a ratio of 2% by mass with respect to the toner base particles, and externally added under the following conditions. .

The spherical mixing tank has the same structure as in Example 1, but the ratio of the width (L ₂ ) of the workpiece flow regulating plate to the radius is 0.18, and the ratio of the length (L ₁ ) to the circumference is 0. .15, θ = 35 °, the distance of the shortest gap between the workpiece flow regulating plate and the tank inner wall is 7.0 mm, and the tip of the workpiece flow regulating plate farther from the rotation axis direction than the tank bottom The difference between the height and the height of the cylindrical member tip from the tank bottom (positive when the tip of the workpiece flow regulating plate is low) is 150 mm, and the workpiece flow regulating plate closer to the rotation axis The distance (gap) from the inner wall of the tank was 50 mm. This spherical mixing treatment tank was mixed with a seal air amount of 1.0 Nm ³ / h, a peripheral speed of the turbine blades of 60 m / s, and a mixing time of 2 minutes.

  The ratio (yield) of the recovered weight to the input weight of the object to be processed was 97.6%. Further, the number free rate of silica fine particles in the obtained toner was 1.1% by number, and the amount of free toner base particles was 25.0% by number.

  Next, the obtained toner was loaded into a toner cartridge of a color printer (“LP9000C” manufactured by Seiko Epson Corporation), and solid printing was performed. After printing, the toner cartridge was taken out and the toner charge amount distribution on the developing roller was measured in the same manner as in Example 1. As a result, the amount of positively charged toner was 6.8% by number. The standard deviation (μC / g) of the ratio (Q / m) to the obtained mass was 18.7.

  The yield was high, the amount of free external additive and the amount of positively charged toner was small, and a uniform external addition process with a narrow charge amount distribution was achieved.

  In the production of the toner base particles of Example 1, the wax emulsion was adjusted to 10 parts by mass and the temperature and time were adjusted in the aggregation process of the secondary particles to obtain an average particle diameter of 7.5 μm, a flow softening point (Tf1 / 2). The toner base particles were 128.2 ° C., ML2 / A was 1.30, and PM2 / A was 1.25.

  2.8 kg of the obtained toner base particles were placed in a spherical mixing tank (Mitsui Mine Co., Ltd., Q-type 20L, the stirring blade was a turbine blade, and attached to the inner wall position that was 1/16 of the circumference from the top of the processing tank. The workpiece flow restriction plate is attached to the support member at a position where the full length of the restriction plate is divided 1: 4 so that the length of the end surface on the top side of the treatment tank from the support member is reduced, and the jacket has a water temperature of 25 ° C. After passing water at a rate of 35 liters / min, the rotating shaft is cooled with water, and charged with seal air to prevent the intrusion of the object to be processed), silica fine particles {RX200 manufactured by Nippon Aerosil Co., Ltd. (average particle size 12 nm) And silica fine particles {A mixture of 1: 1 (mass ratio) RX50 (average particle diameter 40 nm) manufactured by Nippon Aerosil Co., Ltd. at a ratio of 2% by mass with respect to the toner base particles, and externally added under the following conditions. .

The spherical mixing tank has the same structure as in Example 1, but the ratio of the width (L ₂ ) of the workpiece flow regulating plate to the radius is 0.22, and the ratio of the length (L ₁ ) to the circumference is 0. .18, θ = 40 °, the distance of the shortest gap between the workpiece flow regulating plate and the tank inner wall is 3.5 mm, and the tip of the workpiece flow regulating plate farther from the rotation axis direction than the tank bottom The difference between the height and the height of the cylindrical member tip from the tank bottom (positive when the tip of the workpiece flow regulating plate is low) is 25 mm, and the workpiece flow regulating plate closer to the rotation axis The distance of the gap between the tank inner walls was 12.5 mm. This spherical mixing tank was mixed with a seal air amount of 1.0 Nm ³ / h, a turbine blade peripheral speed of 47 m / s, and a mixing time of 2 minutes.

  The ratio (yield) of the recovered weight to the input weight of the workpiece was 97.0%. Further, the number free rate of silica fine particles in the obtained toner was 1.0% by number, and the amount of free toner base particles was 26.0% by number.

  Next, the obtained toner was loaded into a toner cartridge of a color printer (“LP9000C” manufactured by Seiko Epson Corporation), and solid printing was performed. After printing, the toner cartridge was taken out, and the toner charge amount distribution on the developing roller was measured in the same manner as in Example 1. As a result, the amount of positively charged toner was 7.2% by number. The standard deviation (μC / g) of the ratio (Q / m) to the obtained mass was 20.4.

The yield was high, the amount of free external additive and the amount of positively charged toner was small, and a uniform external addition process with a narrow charge amount distribution was achieved.
(Comparative example)
In the production of the toner base particles of Example 1, 25 parts by weight of the wax emulsion was used, and the temperature and time were adjusted in the secondary particle aggregation process to obtain an average particle size of 6.9 μm and a flow softening point (Tf1 / 2) of 105. The toner base particles were obtained at .2 ° C., ML2 / A of 1.04, and PM2 / A of 1.04.

  As shown in FIG. 5, the resulting toner base particles (3.0 kg) are spherical mixing tanks (Q type 20L, manufactured by Mitsui Mining Co., Ltd.), and the stirring blades are turbine blades. In the jacket, water at a temperature of 25 ° C. is passed through the jacket at a rate of 25 liters / min, and the rotating shaft is cooled with water and has a structure that prevents the entry of the object to be processed with seal air). Add a 1: 1 (mass ratio) mixed powder of Aerosil RX200 (average particle size 12 nm) and silica fine particles {Japan Aerosil RX50 (average particle size 40 nm) at a ratio of 2% by mass to the toner base particles. Then, external treatment was performed under the following conditions.

  The spherical mixing tank has an internal volume of 20 liters, the length of the cylindrical member 7 inside the container is 1/11 of the height from the donut disk 4 inside the container, and the diameter of the tank bottom 2 and the processing tank The ratio of the diameter of 1 to 0.57, the ratio of the outer diameter of the donut disk 4 to the diameter of the horizontal tank bottom 2 is 1.10, the ratio of the diameter of the turbine blade 11 to the diameter of the treatment tank 1 Is 0.75, and the ratio of the inner diameter to the outer diameter of the donut disk 4 is 0.73.

Further, the ratio of the width (L ₂ ) of the workpiece flow regulating plate shown in FIG. 5 to the radius on the inner wall surface side of the tank is 0.5, and the ratio of the length (L ₁ ) to the peripheral length on the inner wall surface side of the tank is 0. .3, θ = −45 ° shown in FIG. 6 (the direction toward the flow direction of the object to be processed is positive), the shortest gap between the upper end of the fan-shaped surface of the object flow regulating plate and the inner wall of the tank The distance is 0 mm, and the difference between the height from the tank bottom of the tip portion farther than the rotational axis direction in the workpiece flow regulating plate and the height from the vessel bottom of the cylindrical member tip (tip of the workpiece flow regulating plate) -70 mm, and the distance (gap) between the workpiece flow regulating plate closer to the rotation axis and the inner wall of the tank was 3.0 mm.

This spherical mixing treatment tank was mixed with a seal air amount of 1.0 Nm ³ / h, a turbine blade peripheral speed of 55 m / s, and a mixing time of 2 minutes. The peripheral speed of the turbine blade was calculated from the outermost diameter of the blade and the rotational speed.

  The ratio (yield) of the recovered weight to the input weight of the object to be processed was 92.5%. Further, the number free rate of silica fine particles in the obtained toner was 2.5% by number, and the amount of free toner base particles was 35.7% by number.

  Next, the obtained toner was loaded into a toner cartridge of a color printer (“LP9000C” manufactured by Seiko Epson Corporation), and solid printing was performed. After printing, the toner cartridge was taken out, and the toner charge amount distribution on the developing roller was measured. For the measurement, a charge amount distribution measuring device (“E-SPART III” manufactured by Hosokawa Micron Corporation) was used, and the number of measurement was 3000. The positively charged toner amount was 18.2% by number, and the standard deviation (μC / g) of the ratio (Q / m) between the charge amount and the mass determined from the particle diameter was 34.9.

FIG. 1 is a central sectional view of a spherical mixing treatment tank. FIG. 2 is a plan view of an example of a stirring blade. FIG. 3 is a view showing a state where the upper hemisphere portion of the mixed treatment layer is opened from the flange portion and viewed from the inside. FIG. 4 is a central sectional view of the Henschel type mixing treatment tank. FIG. 5 is a central sectional view of a spherical mixing treatment tank shown as a comparison. FIG. 6 is a view showing a state in which the upper hemisphere portion of the mixed treatment layer shown in FIG. 5 is opened from the flange portion and viewed from the inside.

Explanation of symbols

1 is a spherical mixing treatment tank, 2 is a horizontal disk-shaped tank bottom, 3 is a rotary drive shaft, 4 is a donut-shaped disk, 5 is a stirring blade, 6 is an air seal hole, 7 is a cylindrical member, 8 is a flange, 9 is a jacket, 11 is an agitating blade (turbine blade), 12 is an object flow regulating plate, and 13 is a mounting member.

Claims (9)

In a toner manufacturing method using a spherical mixing tank, the spherical mixing tank is covered with a horizontal disk-shaped tank bottom and a rotary drive shaft that vertically penetrates the center of the horizontal disk-shaped tank bottom. A stirring blade that discharges the processed material spirally upward along the inner wall of the processing tank is attached, and a cylindrical member that vertically penetrates the top of the mixing processing layer on the extension line of the rotation drive shaft has its tip end in the mixing processing tank. It is arranged so that it is located at the top of the tank, and the object to be processed that is released spirally upward by the rotation of the stirring blade is moved to the top of the tank to reduce its kinetic energy, and the object to be processed is re-supplied to the stirring blade at the bottom of the tank In addition, a support member that penetrates the tank wall of the mixing treatment tank is provided, and the flow direction of the object to be processed is changed to the rotation axis direction of the rotation drive shaft in the upper hemisphere of the mixing treatment tank. Structure with a flow control plate In the mixing treatment tank, the shape factor (ML2 / A) is 1.05-1.40, the shape factor (PM2 / A) is 1.05-1.30, and the flow A method for producing a toner, comprising adding spherical resin particles containing at least a colorant having a softening point (Tf1 / 2) of 100 to 130 ° C. and external additive particles and mixing the particles. 2. The toner production method according to claim 1, wherein the external additive particles are a mixture of hydrophobic silica fine particles having an average particle diameter of 5 nm to 50 nm and hydrophobic silica fine particles having an average particle diameter of 80 nm to 500 nm. 2. The toner production method according to claim 1, wherein in the mixed toner, the amount of free toner base particles measured by a particle analyzer is 40% by number or less. In a toner manufacturing apparatus comprising a spherical mixing treatment tank for mixing and processing spherical resin particles containing at least a colorant and external additive particles as an object to be processed, the spherical mixing treatment tank has a horizontal disk-shaped tank bottom. And an agitating blade for discharging the workpiece spirally along the inner wall of the treatment tank to a rotation drive shaft that vertically penetrates the center of the horizontal disk-shaped tank bottom, and on the extension line of the rotation drive shaft A cylindrical member that vertically penetrates the top of the mixing treatment layer is arranged so that the tip thereof is located in the mixing treatment tank, and the object to be processed, which is released spirally upward by the rotation of the stirring blade, is moved to the top of the tank. The kinetic energy is reduced to re-supply the object to be stirred to the stirring blade at the bottom of the tank, and a support member penetrating the tank wall of the mixing treatment tank is provided. The flow direction of the workpiece in the hemisphere It has a structure in which a workpiece flow regulating plate that is changed in the direction of the rotation axis of the rolling drive shaft is attached, and the shape factor (ML2 / A) of the spherical resin particles in the workpiece is 1.05 to 1. 40, a toner having a shape factor (PM2 / A) of 1.05 to 1.30, and a flow softening point (Tf1 / 2) of 100 to 130 ° C. The surface of the workpiece flow regulating plate facing the workpiece is a fan-shaped surface, and the fan-shaped surface is in a direction in which the workpiece flows from a direction perpendicular to the direction in which the workpiece flows. It is attached to the support member so as to face each other in the range of 0 ° to 90 °, and the shape of the upper edge of the fan-shaped surface is made to correspond to the shape of the inner wall of the mixing treatment tank. The toner manufacturing apparatus according to claim 4, wherein the closest approach gap with the inner wall of the tank is 1 mm to 30 mm. In the gap between the upper edge of the fan-shaped surface and the inner wall of the mixing treatment tank, the gap between the upper edge edge portion farther than the rotation axis direction of the rotation drive shaft and the inner wall of the mixing treatment tank is narrower and closer to the rotation axis direction of the rotation drive shaft. 6. The toner manufacturing apparatus according to claim 5, wherein a gap between the upper end edge of one side and the inner wall of the mixing treatment tank is widened. The tip of the workpiece flow regulating plate, which is farther from the rotation axis direction of the rotation drive shaft, is higher than the attachment position of the stirring blade and is attached to a position lower than the tip of the cylindrical member in the tank. 6. The toner manufacturing apparatus according to claim 5, wherein the flow of the product is changed in the direction of the rotation axis of the rotation drive shaft. 6. The toner according to claim 5, wherein the length of the upper edge of the fan-shaped surface of the workpiece flow regulating plate is set to 1/10 to 1/4 of the circumference when the inner surface of the processing tank is a sphere. Manufacturing equipment. 6. A toner manufacturing apparatus according to claim 5, wherein the width of the fan-shaped surface of the workpiece flow regulating plate is set to 1/10 to 1/1 of the radius when the inner surface of the processing tank is a sphere. .

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