JP2011070035A - Method for producing toner for single-component developer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a toner for a single-component developer, the toner causing no melt sticking of the toner on a regulating blade and suppressing aggregation even in long-term printing. <P>SOLUTION: The method for producing a toner includes: a spraying step where crosslinking resin fine particles are adhered to the surfaces of toner base particles to form a toner with the crosslinking resin fine particles adhering thereto, by spraying a spray liquid, which is prepared by dispersing the crosslinking resin fine particles in a volatile liquid by addition of ultrasonic vibrations, to toner base particles in a fluidized state in a powder flow passage; and a crosslinking resin fine particle-fixing step where an impact is applied to the toner with the crosslinking resin fine particles adhering thereto, so as to fix the crosslinking resin fine particles to the surfaces of the toner base particles to form the toner with crosslinking resin fine particles fixed thereto. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for producing a toner for a one-component developer.

  In recent years, image forming apparatuses have been increased in speed and life, and a non-magnetic one-component development system has been adopted for full-color image formation. In the image formation by the one-component development method, a developing roller disposed close to the photosensitive member, a supply roller for supplying toner to the developing roller, and a thin layer against the toner on the peripheral surface of the developing roller in contact with the developing roller And a developing device including a regulating blade that performs charge and charge application. In this developing system, in order to properly visualize the electrostatic latent image formed on the surface of the photoreceptor, it is necessary to always form a stable thin toner layer on the developing roller.

  Since the binder resin used for the toner for forming a full-color image has a low softening point, the toner is more easily fused or fixed to the regulating blade than the black toner. When the toner is fused or fixed to the regulating blade, there is a problem in that a uniform thin layer of toner is not formed on the peripheral surface of the developing roller, and white streaks or the like are generated on the image, leading to deterioration of image quality. In addition, sufficient charge is not applied to the toner, causing problems such as background fogging on the image and toner scattering in the image forming apparatus.

  To solve such a problem, Patent Document 1 discloses a toner in which fusion to a regulating blade is suppressed by including thermosetting resin fine particles as an external additive.

JP 2001-166533 A

  However, when resin fine particles are added as an external additive, the adhesion force of the resin fine particles to the toner base particles is not sufficient, and when the toner is used as a one-component developer for a long time, the resin fine particles are detached from the toner base particles. As a result, there is a problem in that toner fusing to the regulating blade and chargeability variation occur.

  An object of the present invention is to provide a method for producing a toner for a one-component developer in which the toner is not fused to a regulating blade even in long-term printing and aggregation is suppressed.

The present invention provides a toner base particle by spraying a spray liquid in which crosslinked resin fine particles are dispersed in a volatile liquid by applying ultrasonic vibration to the toner base particles in a fluid state in a powder channel. A spraying step in which crosslinked resin fine particles are adhered to the surface to form a crosslinked resin fine particle-adhered toner;
And a cross-linked resin fine particle fixing step of applying a shock to the cross-linked resin fine particle-adhered toner to fix the cross-linked resin fine particles on the surface of the toner base particles to form a cross-linked resin fine particle-fixed toner. A toner manufacturing method.

  In the cross-linked resin fine particle fixing step, the present invention may be configured to apply the impact to the cross-linked resin fine particle-adhered toner using a rotary stirring unit including a rotary shaft and rotary blades provided radially on the rotary shaft. Features.

According to the present invention, in the spraying step, a spray liquid storage section that stores the spray liquid, a nozzle that supplies the spray liquid into a powder flow path, and a feed that supplies a predetermined amount of the spray liquid to the nozzle. Spraying the spray liquid using a spray means comprising a liquid pump and an ultrasonic vibrator for applying ultrasonic vibration to the spray liquid,
The spray liquid storage unit includes a stirring unit, and the spray liquid is stored in the spray liquid storage unit in a state of being stirred by the stirring unit.
Further, the invention is characterized in that the crosslinked resin fine particles are melamine resin particles.

  According to the present invention, since the volatile liquid in which the crosslinked resin fine particles are dispersed is sprayed on the toner base particles, the movement of the crosslinked resin fine particles on the surface of the toner base particles is suppressed by the surface tension of the liquid, and the crosslinked resin fine particles are The toner particles can be uniformly adhered to the entire surface of the toner base particles without concentrating on the concave portions of the particle surface. Further, by applying ultrasonic vibration to the spray liquid, the aggregation of the crosslinked resin fine particles can be suppressed, and even if the addition amount is small, the crosslinked resin fine particles can be uniformly adhered and fixed to the entire surface of the toner base particles. . As a result, a toner for one-component developer having no toner fusion to the regulating blade, suppressing aggregation, and having excellent fixability can be obtained.

  Further, according to the present invention, in the cross-linked resin fine particle fixing step, the impact is applied to the cross-linked resin fine particle-adhered toner using the rotary stirring means having a rotation shaft and rotary blades provided radially on the rotation shaft. Therefore, it is possible to efficiently obtain a toner in which crosslinked resin fine particles are uniformly fixed on the entire surface of the toner base particles without aggregation.

  According to the invention, since the spray liquid storage unit includes the stirring unit, and the spray liquid is stored in the spray liquid storage unit in a state of being stirred by the stirring unit, mixing of the crosslinked resin fine particles and the volatile liquid is performed. The ratio can be kept constant. As a result, the crosslinked resin fine particles can be more uniformly attached to the entire surface of the toner base particles.

  Further, according to the present invention, since the crosslinked resin fine particles are melamine resin particles, toner fusion to the regulating blade is suppressed, and a toner excellent in chargeability can be obtained.

FIG. 6 is a process diagram illustrating an example of a procedure of a toner manufacturing method according to the present invention. FIG. 3 is a front view showing a configuration of a toner manufacturing apparatus 201 used in the toner manufacturing method of the present invention. FIG. 3 is a schematic cross-sectional view of the toner manufacturing apparatus 201 shown in FIG. 2 as viewed from a cutting plane line A200-A200. It is a front view of the nozzle which provided the ultrasonic transducer | vibrator 203b in the outer side of the two-fluid nozzle 203a. FIG. 3 is a side view showing a configuration around a powder input unit 206 and a powder recovery unit 207.

1. Toner Manufacturing Method FIG. 1 is a process diagram showing an example of the procedure of a toner manufacturing method of the present invention. The toner manufacturing method of the present invention includes a toner base particle preparation step S1, a spray liquid preparation step S2, a crosslinked resin fine particle fixing step S3, and an external addition step S4.

(1) Toner mother particle production step S1
In the toner base particle preparation step S1, toner base particles are prepared. The toner base particles are particles containing a binder resin and a colorant, and the production method is not particularly limited and can be produced by a known method. Examples of the method for producing the toner base particles include a dry method such as a pulverization method, a wet polymerization method such as a suspension polymerization method, an emulsion aggregation method, a dispersion polymerization method, a dissolution suspension method, and a melt emulsification method. Hereinafter, a method for producing toner base particles by a pulverization method will be described.

  In the method for preparing toner base particles using the pulverization method, the toner base particle raw materials containing a binder resin, a colorant and other additives are dry-mixed with a mixer and then melt-kneaded with a kneader. The kneaded product obtained by melt kneading is cooled and solidified, and the solidified product cooled and solidified is pulverized by a pulverizer. Thereafter, particle size adjustment such as classification is performed as necessary to obtain toner mother particles.

  Known mixers can be used, such as Henschel mixer (trade name, manufactured by Mitsui Mining Co., Ltd.), super mixer (trade name, manufactured by Kawata Co., Ltd.), Mechano Mill (trade name, manufactured by Okada Seiko Co., Ltd.), etc. Henschel type mixing device, Ong mill (trade name, manufactured by Hosokawa Micron Corporation), hybridization system (trade name, manufactured by Nara Machinery Co., Ltd.), Cosmo system (trade name, manufactured by Kawasaki Heavy Industries, Ltd.), and the like.

  As the kneading machine, a known kneading machine can be used. For example, a general kneading machine such as a twin-screw extruder, a triple roll, a lab blast mill can be used. More specifically, for example, TEM-100B (trade name, manufactured by Toshiba Machine Co., Ltd.), PCM-65 / 87, PCM-30 (all of which are trade names, manufactured by Ikegai Co., Ltd.), etc. Extruder, Needex (trade name, manufactured by Mitsui Mining Co., Ltd.) and other open roll type kneaders. Among these, an open roll type kneader is preferable.

  As the pulverizer, for example, a jet type pulverizer that pulverizes using a supersonic jet stream, and a solidified material in a space formed between a rotor (rotor) and a stator (liner) that rotate at high speed. An impact pulverizer that introduces and pulverizes can be used.

  For the classification, a known classifier capable of removing the excessively pulverized toner base particles by classification by centrifugal force and classification by wind force can be used. For example, a swirling wind classifier (rotary wind classifier) can be used.

(Toner base material)
As described above, the toner base particles include a binder resin and a colorant. The binder resin is not particularly limited, and a known binder resin for black toner or color toner can be used. For example, styrene-based resins such as polystyrene and styrene-acrylate copolymer resin can be used. Examples thereof include resins, acrylic resins such as polymethyl methacrylate, polyolefin resins such as polyethylene, polyesters, polyurethanes, and epoxy resins. Moreover, you may use resin obtained by mixing a raw material monomer mixture with a mold release agent and performing a polymerization reaction. Binder resin can be used individually by 1 type, or can use 2 or more types together.

  Among these binder resins, polyester is excellent in transparency and can impart good powder fluidity, low-temperature fixability, secondary color reproducibility, etc. to toner particles, and is therefore suitable as a binder resin for color toners. It is. Known polyesters can be used, and examples thereof include polycondensates of polybasic acids and polyhydric alcohols.

  As the polybasic acid, those known as polyester monomers can be used, for example, terephthalic acid, isophthalic acid, phthalic anhydride, trimellitic anhydride, pyromellitic acid, naphthalenedicarboxylic acid and other aromatic carboxylic acids, maleic anhydride, Examples thereof include aliphatic carboxylic acids such as fumaric acid, succinic acid, alkenyl succinic anhydride, and adipic acid, and methyl esterified products of these polybasic acids. A polybasic acid can be used individually by 1 type, or can use 2 or more types together.

  As the polyhydric alcohol, those known as monomers for polyesters can be used. For example, aliphatic polyhydric alcohols such as ethylene glycol, propylene glycol, butanediol, hexanediol, neopentylglycol, glycerin, cyclohexanediol, cyclohexanediene, etc. Examples thereof include aromatic diols such as alicyclic polyhydric alcohols such as methanol and hydrogenated bisphenol A, ethylene oxide adducts of bisphenol A, and propylene oxide adducts of bisphenol A. A polyhydric alcohol can be used individually by 1 type, or can use 2 or more types together.

  The polycondensation reaction between the polybasic acid and the polyhydric alcohol can be carried out according to a conventional method, for example, by contacting the polybasic acid with the polyhydric alcohol in the presence of an organic volatile liquid and a polycondensation catalyst. The process is terminated when the acid value, softening temperature, etc. of the polyester to be produced reach a predetermined value. Thereby, polyester is obtained. In some cases, organic volatile liquids may not be used.

  When a methyl esterified product of a polybasic acid is used as a part of the polybasic acid, a demethanol polycondensation reaction is performed. In this polycondensation reaction, for example, the carboxyl group content at the end of the polyester can be adjusted by appropriately changing the mixing ratio of polybasic acid and polyhydric alcohol, the reaction rate, etc., and thus the properties of the resulting polyester are changed. be able to. A modified polyester can also be obtained by using trimellitic anhydride as a polybasic acid and introducing a carboxyl group into the main chain of the polyester. Alternatively, a polyester in which a hydrophilic group such as a carboxyl group or a sulfonic acid group is bonded to the main chain and / or side chain of the polyester to impart self-dispersibility in water can also be used. Furthermore, a resin obtained by grafting polyester and acrylic resin can also be used.

  The binder resin preferably has a glass transition temperature of 30 ° C. or higher and 80 ° C. or lower. If the glass transition temperature of the binder resin is less than 30 ° C., the toner is likely to thermally aggregate inside the image forming apparatus and blocking is likely to occur, which may reduce storage stability. When the glass transition temperature of the binder resin exceeds 80 ° C., the fixability of the toner to the recording medium is lowered, and there is a possibility that fixing failure occurs.

  Examples of the colorant include black, yellow, orange, red, purple, blue, green and white colorants. Organic dyes, organic pigments, inorganic dyes, inorganic pigments and the like commonly used in the electrophotographic field Can be used.

  Examples of the black colorant include carbon black, copper oxide, manganese dioxide, aniline black, activated carbon, nonmagnetic ferrite, magnetic ferrite, and magnetite.

  Examples of yellow colorants include chrome lead, zinc yellow, cadmium yellow, yellow iron oxide, mineral fast yellow, nickel titanium yellow, navel yellow, naphthol yellow S, Hansa yellow G, Hansa yellow 10G, benzidine yellow G, and benzidine. Yellow GR, Quinoline Yellow Lake, Permanent Yellow NCG, Tartrazine Lake, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 13, C.I. I. Pigment yellow 14, C.I. I. Pigment yellow 15, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 74, C.I. I. Pigment yellow 93, C.I. I. Pigment yellow 94, C.I. I. Pigment yellow 138, C.I. I. Pigment yellow 180, C.I. I. And CI Pigment Yellow 185.

  Examples of the orange colorant include red chrome yellow, molybdenum orange, permanent orange GTR, pyrazolone orange, vulcan orange, indanthrene brilliant orange RK, benzidine orange G, indanthrene brilliant orange GK, C.I. I. Pigment orange 31, C.I. I. And CI Pigment Orange 43.

  Examples of red colorants include bengara, cadmium red, red lead, mercury sulfide, cadmium, permanent red 4R, risol red, pyrazolone red, watching red, calcium salt, lake red C, lake red D, and brilliant carmine 6B. Eosin Lake, Rhodamine Lake B, Alizarin Lake, Brilliant Carmine 3B, C.I. I. Pigment red 2, C.I. I. Pigment red 3, C.I. I. Pigment red 5, C.I. I. Pigment red 6, C.I. I. Pigment red 7, C.I. I. Pigment red 15, C.I. I. Pigment red 16, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 53: 1, C.I. I. Pigment red 57: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 123, C.I. I. Pigment red 139, C.I. I. Pigment red 144, C.I. I. Pigment red 149, C.I. I. Pigment red 166, C.I. I. Pigment red 177, C.I. I. Pigment red 178, C.I. I. And CI Pigment Red 222.

  Examples of purple colorants include manganese purple, fast violet B, and methyl violet lake.

  Examples of blue colorants include bitumen, cobalt blue, alkali blue lake, Victoria blue lake, phthalocyanine blue, metal-free phthalocyanine blue, phthalocyanine blue partially chlorinated products, first sky blue, induslen blue BC, C.I. I. Pigment blue 15, C.I. I. Pigment blue 15: 2, C.I. I. Pigment blue 15: 3, C.I. I. Pigment blue 16, C.I. I. And CI Pigment Blue 60.

  Examples of the green colorant include chrome green, chromium oxide, pigment green B, micalite green lake, final yellow green G, C.I. I. And CI Pigment Green 7.

  Examples of the white colorant include compounds such as zinc white, titanium oxide, antimony white, and zinc sulfide.

  One colorant can be used alone, or two or more different colorants can be used in combination. Moreover, even if it is the same color, 2 or more types can be used together. The amount of the colorant to be used is not particularly limited, but is preferably 5 parts by weight or more and 20 parts by weight or less, more preferably 5 parts by weight or more and 10 parts by weight or less with respect to 100 parts by weight of the binder resin.

  The colorant may be used as a master batch in order to uniformly disperse it in the binder resin. Two or more colorants may be used in the form of composite particles. The composite particles can be produced, for example, by adding an appropriate amount of water, lower alcohol or the like to two or more colorants, granulating with a general granulator such as a high speed mill, and drying. The master batch and the composite particles are mixed into the toner base particle raw material during dry mixing.

  The toner base particles may contain a charge control agent in addition to the binder resin and the colorant. As the charge control agent, a charge control agent for positive charge control and negative charge control commonly used in this field can be used.

  Examples of charge control agents for controlling positive charge include nigrosine dyes, basic dyes, quaternary ammonium salts, quaternary phosphonium salts, aminopyrines, pyrimidine compounds, polynuclear polyamino compounds, aminosilanes, nigrosine dyes and derivatives thereof, and triphenylmethane. Derivatives, guanidine salts, amidine salts and the like can be mentioned.

  Charge control agents for controlling negative charges include oil-soluble dyes such as oil black and spiron black, metal-containing azo compounds, azo complex dyes, metal salts of naphthenic acid, metal salts of salicylic acid and its derivatives (metals are metal Chromium, zinc, zirconium, etc.), boron compounds, fatty acid soaps, long-chain alkyl carboxylates, resin acid soaps, and the like. A charge control agent can be used individually by 1 type, or can use 2 or more types together as needed. The amount of the charge control agent used is not particularly limited and can be appropriately selected from a wide range, but is preferably 0.5 parts by weight or more and 3 parts by weight or less with respect to 100 parts by weight of the binder resin.

  Further, the toner base particles may contain a release agent in addition to the binder resin and the colorant. As the release agent, those commonly used in this field can be used, for example, petroleum wax such as paraffin wax and derivatives thereof, microcrystalline wax and derivatives thereof, Fischer-Tropsch wax and derivatives thereof, polyolefin wax (polyethylene wax, polypropylene Wax etc.) and derivatives thereof, low molecular weight polypropylin wax and derivatives thereof, hydrocarbon polymer waxes such as polyolefin polymer wax (low molecular weight polyethylene wax etc.) and derivatives thereof, carnauba wax and derivatives thereof, rice wax and derivatives thereof , Candelilla wax and its derivatives, plant wax such as wood wax, animal wax such as beeswax and whale wax, fatty acid amide, phenol fatty acid ester, etc. Oil-based synthetic waxes, long-chain carboxylic acids and their derivatives, long-chain alcohols and derivatives thereof, silicon-based polymers, such as higher fatty acids. Derivatives include oxides, block copolymers of vinyl monomers and waxes, graft modified products of vinyl monomers and waxes, and the like.

  The amount of the release agent used is not particularly limited and can be appropriately selected from a wide range, but is preferably 0.2 parts by weight or more and 20 parts by weight or less, more preferably 0.5 parts by weight or more with respect to 100 parts by weight of the binder resin. 10 parts by weight or less.

  The volume average particle diameter of the toner base particles is preferably 4 μm or more and 8 μm or less. When the volume average particle diameter of the toner base particles is 4 μm or more and 8 μm or less, a high-definition image can be stably formed over a long period of time. Further, by reducing the toner base particles within this range, a high image density can be obtained even if the amount of adhesion is small, and the toner consumption can be reduced. If the volume average particle size of the toner base particles is less than 4 μm, the toner base particles have a small particle size, and thus there is a risk of high charge and low fluidity. If the toner is highly charged and fluidized, the toner cannot be stably supplied to the photoconductor, which may cause background fogging and a decrease in image density. If the volume average particle size of the toner base particles exceeds 8 μm, the toner base particles have a large particle size, so that the cross-linked resin fine particle occupancy ratio on the surface of the toner in the formed image becomes high, resulting in an image with remarkable granularity and high definition. I cannot get a good image. Further, as the toner base particle size increases, the specific surface area decreases and the toner charge amount decreases. When the charge amount of the toner is small, the toner is not stably supplied to the photoconductor, and there is a possibility that in-machine contamination due to toner scattering occurs.

(2) Spray liquid preparation step S2
In the spray liquid preparation step S2, the volatile liquid and the crosslinked resin fine particles are mixed to prepare the spray liquid.

(Volatile liquid)
The volatile liquid needs to be a liquid that has an effect of plasticizing the toner base particles without dissolving them and is easy to evaporate. Examples of such a liquid include a liquid containing a lower alcohol. Examples of the lower alcohol include methanol, ethanol, propanol, and butanol, and alcohols having 4 or less carbon atoms in the molecule are more preferable. Such an alcohol has a low viscosity, and when sprayed from the spraying means, the spray droplet diameter does not become coarse, so that it is possible to spray a fine liquid with a uniform spray droplet diameter.

  In addition, since the nozzle is easily clogged with only the lower alcohol, a volatile liquid having higher liquid retention than the lower alcohol can be mixed and used. Such volatile liquids include water, octanol, decyl alcohol, diethylene glycol, glycerin, polyethylene glycol, alcohols such as phenol, benzyl alcohol, methyl benzyl alcohol, acetone, methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone, diethyl ketone. Ketones such as methyl ethyl ether, diethyl ether, methyl butyl ether, methyl isobutyl ether, dimethyl ether, diisopropyl ether, octyl phenyl ether, ethers such as methyl acetate, ethyl acetate, ethyl oleate, ethyl acrylate, methyl methacrylate, Esters such as dibutyl succinate, diethyl phthalate, diethyl tartrate, ethyl palmitate, dioctyl phthalate And the like.

(Crosslinked resin fine particles)
As the crosslinked resin fine particles, conventionally known fine particles can be used, and examples include fine particles of melamine resin, acrylic resin, amide resin and the like. Here, the melamine resin is a resin having a crosslinked structure polymerized in a network. In addition, the acrylic resin and the amide resin are, for example, those obtained by crosslinking a linear polymer such as a triacryl monomer or a divinyl monomer with a crosslinking agent or the like to have a crosslinked structure.

  Among these, a melamine resin that exhibits excellent effects on toner fusion to the regulating blade and fluctuations in chargeability is particularly preferable in terms of durability and moisture resistance.

  The number average particle diameter of the primary particles of the crosslinked resin fine particles is preferably 0.1 μm or more and 2 μm or less. By adding such crosslinked resin fine particles having a large particle diameter to the toner base particles and immobilizing them on the surface of the toner base particles, the spacer effect can be maintained over a long period of time. The spacer effect is an effect of improving developability, transferability and cleaning property by reducing the adhesion between toner particles, the adhesion between toner and carrier, and the adhesion between toner and various members, or For example, the toner performance can be maintained by suppressing the burying of the small particle size external additive. The sufficient spacer effect can prevent the toner from being fused to the metal regulating blade by heat. If the number average particle size of the primary particles of the crosslinked resin fine particles is less than 0.1 μm, the spacer effect as described above may not be exhibited. If the number average particle size exceeds 2 μm, the crosslinked resin fine particles may not be sufficiently fixed to the toner.

  The occupation ratio of the crosslinked resin fine particles on the toner surface is preferably 1% or more and 15% or less. When the occupation ratio of the crosslinked resin fine particles on the toner surface is less than 1%, it becomes impossible to prevent the toner from fusing to the metal regulating blade due to heat, and when the occupation ratio exceeds 15%, the toner fixability is improved. descend.

  The spray liquid is prepared, for example, by adding the crosslinked resin fine particles to the volatile liquid exemplified above and dissolving or dispersing the crosslinked resin fine particles in the volatile liquid using a stirrer, an ultrasonic homogenizer or the like.

  The spray liquid preferably contains 5 to 30 parts by weight of the crosslinked resin fine particles with respect to 100 parts by weight of the volatile liquid in which the crosslinked resin fine particles are dispersed. By including the volatile liquid and the crosslinked resin fine particles in such a ratio, the viscosity of the spray liquid becomes suitable, the spray of the spray liquid by the spray means becomes easy, and the state of the surface of the toner base particles softened by the spray of the spray liquid Can be suitably held. When the ratio of the crosslinked resin fine particles is less than 5 parts by weight, the amount of the volatile liquid is large, so that the surface of the toner base particles may be excessively softened, and the time for removing the volatile liquid becomes long. When the ratio of the crosslinked resin fine particles exceeds 30 parts by weight, the viscosity of the spray liquid becomes high, and problems such as clogging of the nozzles of the spray means may occur, which may make it difficult to spray the liquid.

(3) Crosslinked resin fine particle fixing step S3
<Toner production device>
FIG. 2 is a front view showing a configuration of a toner manufacturing apparatus 201 used in the toner manufacturing method of the present invention. FIG. 3 is a schematic cross-sectional view of the toner manufacturing apparatus 201 shown in FIG. 2 as viewed from the cutting plane line A200-A200.

  In the crosslinked resin fine particle fixing step S3, for example, using the toner manufacturing apparatus 201 shown in FIG. 2, the spray liquid prepared in the spray liquid preparing step S2 is sprayed onto the toner base particles prepared in the toner base particle preparing step S1. Then, the cross-linked resin fine particles are adhered to the surface of the toner base particles, and the cross-linked resin fine particles are fixed to the surface of the toner base particles by an impact force by a synergistic effect of circulation and stirring in the apparatus.

  The toner manufacturing apparatus 201 is a rotary stirring device, and includes a powder flow path 202, a spraying means 203, a rotary stirring means 204, a temperature adjustment jacket (not shown), a powder input unit 206, and a powder recovery unit 207. It is comprised including. The rotary stirring means 204 and the powder flow path 202 constitute a circulation means.

(Powder channel)
The powder channel 202 includes a stirring unit 208 and a powder flow unit 209. The stirring unit 208 is a cylindrical container-like member having an internal space. Openings 210 and 211 are formed in the stirring unit 208 which is a rotary stirring chamber. The opening 210 is formed so as to penetrate the side wall including the surface 208a of the stirring unit 208 in the thickness direction at a substantially central portion of the surface 208a on one side in the axial direction of the stirring unit 208. The opening 211 is formed on a side surface 208b perpendicular to the surface 208a on one side in the axial direction of the stirring unit 208 so as to penetrate the side wall including the side surface 208b of the stirring unit 208 in the thickness direction. The powder flow part 209 that is a circulation pipe has one end connected to the opening 210 and the other end connected to the opening 211. As a result, the internal space of the stirring unit 208 and the internal space of the powder flow unit 209 are communicated to form the powder flow path 202. The toner base particles and gas flow through the powder flow path 202. The powder flow path 202 is provided so that the powder flow direction, which is the direction in which the toner base particles flow, is constant.

  The temperature in the powder channel 202 is set to be equal to or lower than the glass transition temperature of the toner base particles, and is preferably 30 ° C. or higher and lower than or equal to the glass transition temperature of the toner base particles. The temperature in the powder flow path 202 is almost uniform in any part due to the flow of the toner base particles. When the temperature in the flow path exceeds the glass transition temperature of the toner base particles, the toner base particles are too soft and the toner base particles may be aggregated. On the other hand, if the temperature is lower than 30 ° C., the drying rate of the dispersion liquid becomes slow and the productivity is lowered. Therefore, in order to prevent aggregation of the toner base particles, it is necessary to maintain the temperature of the powder flow path 202 and the rotary stirring means 204 described later at 30 ° C. or higher and below the glass transition temperature of the toner base particles. Therefore, a temperature adjusting jacket, which will be described later, having an inner diameter larger than the outer diameter of the powder passage tube is disposed on at least a part of the outside of the powder passage 202 and the rotary stirring means 204.

(Rotating stirring means)
The rotating stirring means 204 includes a rotating shaft member 218, a disk-shaped rotating disk 219, and a plurality of stirring blades 220. The rotation shaft member 218 has an axis that coincides with the axis of the stirring unit 208 and is formed on the surface 208c on the other side in the axial direction of the stirring unit 208 so as to penetrate the side wall including the surface 208c in the thickness direction. A cylindrical rod-shaped member that is provided so as to be inserted through 221 and rotates around an axis by a motor (not shown). The rotating disk 219 is a disk-shaped member that is supported by the rotating shaft member 218 so that its axis coincides with the axis of the rotating shaft member 218 and rotates as the rotating shaft member 218 rotates. The plurality of stirring blades 220 are supported by the peripheral portion of the turntable 219 and rotate as the turntable 219 rotates.

  The peripheral speed of the outermost periphery of the rotary stirring means 204 is preferably set to 30 m / sec or more, and more preferably set to 50 m / sec or more. The outermost periphery of the rotary stirring means 204 is a portion 204a of the rotary stirring means 204 having the longest distance from the axis of the rotary shaft member 218 in the direction perpendicular to the direction in which the rotary shaft member 218 of the rotary stirring means 204 extends. When the peripheral speed at the outermost periphery of the rotating stirring means 204 at the time of rotation is 30 m / sec or more, the toner base particles can be isolatedly flowed. When the peripheral speed at the outermost periphery is less than 30 m / sec, the toner base particles cannot be isolated and cannot be fixed uniformly on the surface of the toner base particles.

(Spraying means)
The spray means 203 is provided so as to be inserted into an opening formed in the outer wall of the powder flow path 202, and in the powder flow portion 209, the powder flow closest to the opening portion 211 in the flow direction of the toner mother particles. It is provided in the excess part. The spraying means 203 sprays a spray liquid containing a volatile liquid and fine particles of crosslinked resin adhered to the surface of the toner base particles toward the toner base particles. Following the spray liquid, only the volatile liquid may be sprayed toward the toner base particles. The spray means 203 includes a spray liquid storage section that stores spray liquid, a carrier gas supply section that supplies a carrier gas, and a toner base that contains a mixture obtained by mixing the liquid and the carrier gas in the powder flow path 202. A two-fluid nozzle 203a that sprays liquid droplets onto the toner base particles, a liquid feed pump that supplies a predetermined amount of liquid to the two-fluid nozzle 203a, and an ultrasonic wave that applies ultrasonic vibration to the spray liquid. A sonic transducer 203b.

  Compressed air or the like can be used as the carrier gas. The liquid fed to the spraying means 203 at a constant flow rate by the liquid feed pump, and the liquid sprayed by the spraying means 203 is gasified, and the gasified liquid spreads on the surface of the toner base particles. As a result, the toner base particles are plasticized.

  The two-fluid nozzle 203 a is provided by being inserted through an opening formed in the outer wall of the powder flow path 202.

  In this embodiment, the spray liquid storage part of the spraying means 203 includes a stirring means having a rotating blade (not shown). Accordingly, the spray liquid is stored in a stirred state, and an appropriate amount of the spray liquid in which the crosslinked resin fine particles are dispersed is supplied to the two-fluid nozzle 203a by the liquid feed pump, so that the nozzle can be prevented from being clogged. . Further, since the spray liquid in which the crosslinked resin fine particles are dispersed is sent to the two-fluid nozzle 203a at a constant flow rate and sprayed into the powder flow path 202, the spray liquid concentration in the powder flow path is stabilized. In addition, the occupation ratio of the crosslinked resin fine particles on the toner surface can be controlled.

  FIG. 4 is a front view of a nozzle provided with an ultrasonic transducer 203b outside the two-fluid nozzle 203a. By driving the ultrasonic vibrator 203b, ultrasonic vibration can be applied to the spray liquid sent into the two-fluid nozzle 203a, and the crosslinked resin fine particles can be sufficiently dispersed, thereby preventing nozzle clogging. Can do. A known ultrasonic transducer can be used as the ultrasonic transducer 203b. In this embodiment, an ultrasonic vibrator (type: D4520) manufactured by Nippon Special Ceramics Co., Ltd. is used.

(Temperature adjustment jacket)
A temperature adjusting jacket (not shown), which is a temperature adjusting means, is provided in at least a part of the outside of the powder flow path 202, and a cooling medium or a heating medium is passed through the space inside the jacket through the powder flow path 202 and the rotating stirring means 204 is adjusted to a predetermined temperature. This makes it possible to control the temperature inside the powder channel and outside the rotary stirring means to a temperature at which the toner base particles are not softened and deformed.

  In the present embodiment, the temperature adjustment jacket is preferably provided on the entire outside of the powder flow path 202. As a result, toner mother particles can be prevented from adhering to the inner wall of the powder flow path 202 due to an excessive temperature rise, and the inside of the powder flow path 202 can be prevented from becoming narrow. As a result, a toner in which the crosslinked resin fine particles are uniformly fixed on the surface of the toner base particles can be produced with a high yield.

(Powder input part and powder recovery part)
A powder input unit 206 and a powder recovery unit 207 are connected to the powder flow unit 209 of the powder channel 202. FIG. 5 is a side view showing the configuration around the powder input unit 206 and the powder recovery unit 207.

  The powder input unit 206 includes a hopper (not shown) that supplies toner mother particles, a supply pipe 212 that communicates the hopper and the powder flow path 202, and an electromagnetic valve 213 provided in the supply pipe 212. The toner mother particles supplied from the hopper are supplied to the powder flow path 202 through the supply pipe 212 in a state where the flow path in the supply pipe 212 is opened by the electromagnetic valve 213. The toner base particles supplied to the powder flow path 202 flow in a constant powder flow direction by stirring by the rotary stirring means 204. When the flow path in the supply pipe 212 is closed by the electromagnetic valve 213, the toner base particles are not supplied to the powder flow path 202.

  The powder recovery unit 207 includes a recovery tank 215, a recovery pipe 216 that communicates the recovery tank 215 and the powder flow path 202, and an electromagnetic valve 217 provided in the recovery pipe 216. In a state where the flow path in the collection pipe 216 is opened by the electromagnetic valve 217, the toner particles flowing through the powder flow path 202 are collected in the collection tank 215 through the collection pipe 216. In addition, when the flow path in the collection pipe 216 is closed by the electromagnetic valve 217, the toner particles flowing through the powder flow path 202 are not collected.

  The crosslinked resin fine particle fixing step S3 using the toner manufacturing apparatus 201 as described above includes a temperature adjusting step S3a, a spraying step S3b, a crosslinked resin fine particle fixing step S3c, and a recovery step S3d. The spraying step S3b and the cross-linked resin fine particle fixing step S3c are preferably performed continuously.

(3) -1 Temperature adjustment step S3a
In the temperature adjustment step S3a, while rotating the rotary stirring means 204, the temperature inside the powder flow path 202 and the rotary stirring means 204 are adjusted to a predetermined temperature through a medium through jackets for temperature adjustment disposed outside them. As a result, the temperature in the powder flow path 202 can be controlled to be equal to or lower than the temperature at which the toner base particles introduced in the spraying step S3b described later are not softened and deformed.

(3) -2 Spraying step S3b
In the spraying step S3b, while the rotating shaft member 218 of the rotary stirring means 204 is rotating, the toner base particles are supplied from the powder input unit 206 to the powder flow path 202, and the toner base particles in a fluid state are supplied to the toner base particles in a fluid state. The spray liquid is sprayed by the carrier gas from the spray means 203. Thereby, a crosslinked resin fine particle-attached toner in which the crosslinked resin fine particles adhere to the surface of the toner base particles is formed.

  The toner base particles supplied to the powder flow path 202 are stirred by the rotary stirring means 204 and flow in the direction of the arrow 214 through the powder flow portion 209 of the powder flow path 202. The spraying of the spray liquid is preferably started after the flow rate of the toner base particles is stabilized in the powder flow path 202. Accordingly, the spray liquid can be uniformly sprayed on the toner base particles, so that the crosslinked resin fine particles can be uniformly attached to the surface of the toner base particles.

  An angle θ formed between the liquid spraying direction which is the axial direction of the two-fluid nozzle of the spraying means 203 and the powder flow direction which is the flow direction of the toner mother particles in the powder flow path 202 is 0 ° or more and 45 ° or less. It is preferable. When θ is within such a range, liquid droplets are prevented from recoiling at the inner wall of the powder flow path 202, and the yield of toner mother particles to which crosslinked resin fine particles are attached can be further improved. . When the angle θ exceeds 45 °, the liquid droplet recoils on the inner wall of the powder flow path 202, the liquid tends to stay, the toner particles agglomerate, and the yield deteriorates.

  The spreading angle φ of the liquid sprayed by the spraying means 203 is preferably 20 ° or more and 90 ° or less. If the spread angle φ is out of this range, it may be difficult to uniformly spray the spray liquid onto the toner base particles.

  The volatile liquid sprayed from the spraying means 203 is discharged out of the powder channel 202 through the through hole 221. A concentration sensor 222 is disposed in a gas discharge part 223 that serves as a passage for gasified volatile liquid discharged outside the powder flow path 202. The concentration of the gasified volatile liquid measured by the concentration sensor 222 is adjusted to about 5% or less in consideration of the drying speed of the volatile liquid, the anti-aggregation property between the toner base particles, the productivity, and the like. Is preferred. As a result, the drying speed of the volatile liquid can be sufficiently increased, so that the cross-linked resin fine particle-adhered toner in which the undried volatile liquid remains can be prevented from adhering. Aggregation can be prevented.

  Further, the exhaust air flow rate discharged to the outside of the powder flow path 202 is the total amount of the carrier gas flow rate and the protective air flow rate sent from the rotary shaft portion into the apparatus for protecting the bearing. The exhaust air flow rate varies depending on the amount of carrier gas supplied into the powder flow path 202. In the present embodiment, the exhaust air flow rate is preferably adjusted to be 10 to 70 L / min. When the discharge air flow rate is less than 10 L / min, the concentration of the gasified volatile liquid in the powder flow path 202 becomes high, and the toner base particles are plasticized. Therefore, aggregation of the toner base particles occurs. The toner yield is reduced. On the other hand, when the discharge air flow rate exceeds 70 L / min, the toner particles are discharged out of the powder flow path 202 together with the carrier gas, so that the toner yield decreases.

(3) -3 Crosslinked resin fine particle fixing step S3c
In the cross-linked resin fine particle fixing step S3c, the stirring of the rotary stirring means 204 is continued at a predetermined temperature until the cross-linked resin fine particles of the toner adhering to the cross-linked resin fine particles are semi-embedded on the surface of the toner base particles. Fine particles are fixed to obtain a crosslinked resin fine particle fixed toner.

(3) -4 Recovery step S3d
In the collecting step S3d, the rotation of the rotary stirring unit 204 is stopped, and the crosslinked resin fine particle fixed toner is discharged from the powder collecting unit 207 to the outside and collected.

  The toner manufacturing apparatus 201 is not limited to the above configuration, and various modifications can be made. For example, the temperature adjustment jacket may be provided on the entire outer surface of the powder flow part 209 and the stirring part 208, or may be provided on a part of the powder flow part 209 or the outside of the stirring part 208. . When the temperature adjustment jacket is provided on the entire surface outside the powder flow section 209 and the stirring section 208, it is possible to more reliably prevent the toner base particles from adhering to the inner wall of the powder flow path 202.

  Further, the toner manufacturing apparatus can be configured by combining a commercially available stirring apparatus and spraying means. As a commercially available stirring apparatus provided with a powder flow path and rotating stirring means, for example, a hybridization system (trade name, manufactured by Nara Machinery Co., Ltd.) and the like can be mentioned. By mounting the liquid spray unit in such a stirring device, this stirring device can be used as a toner manufacturing apparatus used in the toner manufacturing method of the present invention.

(4) External addition process S4
In the external addition step S4, the external additive is prepared by adding an external additive to the recovered crosslinked resin fine particle fixed toner and mixing it with an air flow mixer such as a Henschel mixer.

  Known external additives can be used, and examples thereof include silica, titanium oxide, alumina, cerium oxide, zinc oxide, tin oxide, and zirconium oxide. Among these, silica, alumina, and titanium oxide are particularly preferable because they are excellent in fluidity improvement, triboelectric chargeability improvement, heat resistance improvement, long-term storage stability improvement, cleaning property improvement, and photoreceptor surface wear characteristic control. These are more preferably surface-treated with a hydrophobizing agent such as silicon oil, silane coupling agent, hexamethyldisilazane (HMDS) or the like. The number average particle size of the primary particles of the external additive is preferably 5 nm or more and 100 nm or less. The amount of the external additive used is preferably 1 to 10 parts by weight with respect to 100 parts by weight of the crosslinked resin fine particle fixed toner.

  Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. In the following, “parts” and “%” mean “parts by weight” and “% by weight” unless otherwise specified. The glass transition temperature of the binder resin and toner base particles in the examples and comparative examples, the softening temperature of the binder resin, the melting point of the release agent, the volume average particle diameter of the toner base particles, and the occupation ratio of the crosslinked resin fine particles on the toner surface are as follows: Measurement was performed as follows.

[Glass transition temperature of binder resin and toner base particles]
Using a differential scanning calorimeter (trade name: DSC220, manufactured by Seiko Denshi Kogyo Co., Ltd.), according to Japanese Industrial Standard (JIS) K7121-1987, 1 g of a sample is heated at a heating rate of 10 ° C. per minute and a DSC curve is measured. did. Draw the endothermic peak corresponding to the glass transition of the obtained DSC curve at a point where the slope is maximum with respect to the straight line that extends the base line on the high temperature side to the low temperature side and the curve from the rising part of the peak to the vertex. The temperature at the intersection with the tangent was determined as the glass transition temperature (Tg).

[Softening temperature of binder resin]
Using a flow characteristic evaluation apparatus (trade name: Flow Tester CFT-100C, manufactured by Shimadzu Corporation), 1 g of a sample was heated at a heating rate of 6 ° C. per minute, and a load of 20 kgf / cm ² (9.8 × 10 ⁵ Pa). And the temperature at which half of the sample flowed out from the die (nozzle diameter 1 mm, length 1 mm) was determined, and was defined as the softening temperature (Tm).

[Melting point of release agent]
Using a differential scanning calorimeter (trade name: DSC220, manufactured by Seiko Denshi Kogyo Co., Ltd.), 1 g of the sample is heated from a temperature of 20 ° C. to 200 ° C. at a heating rate of 10 ° C. per minute, and then rapidly cooled from 200 ° C. to 20 ° C. The operation was repeated twice and the DSC curve was measured. The temperature of the endothermic peak corresponding to the melting of the DSC curve measured in the second operation was taken as the melting point of the release agent.

[Volume average particle diameter of toner base particles]
20 ml of a sample and 1 ml of sodium alkyl ether sulfate are added to 50 ml of an electrolytic solution (trade name: ISOTON-II, manufactured by Beckman Coulter, Inc.), and an ultrasonic dispersion device (trade name: desktop type dual frequency ultrasonic cleaner VS-D100). , Manufactured by ASONE Co., Ltd.) for 3 minutes at a frequency of 20 kHz to obtain a measurement sample. About this measurement sample, using a particle size distribution measuring device (trade name: Multisizer III, manufactured by Beckman Coulter, Inc.), measurement is performed under the conditions of aperture diameter: 100 μm, number of measured particles: 50000 count, and from the volume particle size distribution of the sample particles. The volume average particle size was determined.

[Occupancy ratio of crosslinked resin fine particles on toner surface]
The occupation ratio of the crosslinked resin fine particles on the toner surface was determined by the following formula by analyzing the SEM image of the cross-linked resin fine particle fixed toner with respect to the entire surface of the toner base particles.
Occupied area by crosslinked resin fine particles / area of toner mother particle surface × 100 (%)

Example 1
[Toner mother particle production step S1]
100 parts of polyester resin (trade name: Diacron, manufactured by Mitsubishi Rayon Co., Ltd., glass transition temperature 55 ° C., softening temperature 130 ° C.) I. Pigment Blue 15: 3 7.5 parts Release agent (Carnauba wax, melting point 82 ° C.) 7.5 parts Charge control agent (trade name: Bontron E84, manufactured by Orient Chemical Industries, Ltd.)
2.0 parts

  The above raw materials were premixed with a Henschel mixer (trade name: FM20C, manufactured by Mitsui Mining Co., Ltd.) and then melt-kneaded with a twin-screw extrusion kneader (trade name: PCM65, manufactured by Ikegai Co., Ltd.). This melt-kneaded product is coarsely pulverized by a cutting mill (trade name: VM-16, manufactured by Orient Co., Ltd.), then finely pulverized by a jet mill (manufactured by Hosokawa Micron Co., Ltd.), and further by an air classifier (manufactured by Hosokawa Micron Co., Ltd.). Classification was performed to prepare toner base particles A having a volume average particle size of 6.5 μm and a glass transition temperature of 56 ° C.

[Spray liquid preparation step S2]
Volatile liquid: ethanol (molecular weight 46.1, boiling point 78.3 ° C.) 100 parts Crosslinked resin fine particles: melamine particles (average primary particle size 0.2 μm) 10 parts

  The above raw materials were stirred and mixed at 8000 rpm for 5 minutes using a homogenizer (trade name: Polytron PT-MR3100, manufactured by Kinematica) to prepare a spray liquid A.

[Crosslinked resin fine particle fixing step S3]
The toner base particles A are stirred and fluidized by a device in which a two-fluid nozzle is attached to a hybridization system (trade name: NHS-1 type, manufactured by Nara Machinery Co., Ltd.) according to the device shown in FIG. Liquid A was sprayed.

  As a liquid spray unit, a liquid feed pump (trade name: SP11-12, manufactured by Flume Corporation) and a two-fluid nozzle were connected to a cylindrical spray liquid storage tank equipped with rotating blades so that quantitative liquid feeding was possible. I used something. The mounting angle of the two-fluid nozzle was set so that the angle formed between the liquid spraying direction and the toner base particle flow direction was parallel (0 °). Moreover, 300 W of electric power was continuously supplied to the ultrasonic vibrator (manufactured by Nippon Special Ceramics Co., Ltd., type: D4520).

  The liquid spray rate and liquid gas discharge rate were observed using a commercially available gas detector (trade name: XP-3110, manufactured by Shin Cosmos Electric Co., Ltd.).

  The temperature adjusting jacket was provided on the entire surface of the powder flow section and the stirring section wall. A temperature sensor was attached to the powder channel, and the temperature of the powder flow part and the stirring part was adjusted to 55 ° C. The peripheral speed at the outermost periphery of the rotary stirring means was 50 m / sec.

  In a powder flow path (internal volume 26.79 L) of the rotary agitator, 0.4 L (450 g) of toner base particles A are charged and fluidized, and the spray liquid A is sprayed at a spray speed of 5 g / min and a carrier. Spraying was performed at a gas air flow rate of 50 L / min for 15 minutes to adhere melamine particles as crosslinked resin fine particles to the surface of the toner base particles A. At this time, the air flow rate sent into the apparatus was adjusted to 55 L / min with the air flow rate from the two-fluid nozzle adjusted to 5 L / min.

  Thereafter, the spraying of the spray liquid A was stopped, and ethanol was sprayed for 8 minutes at a spraying rate of 0.5 g / min and a carrier gas air flow rate of 10 L / min. At this time, the air flow rate sent into the device was adjusted to 5 L / min from the rotary shaft portion into the device, and the total air flow rate from the two-fluid nozzle was 15 L / min.

  After stopping the spraying of ethanol, the mixture was stirred for 5 minutes to obtain a crosslinked resin fine particle fixed toner A having an occupation ratio of the crosslinked resin fine particles of 8.2% on the toner surface.

[External addition process S4]
100 parts of the recovered crosslinked resin fine particle fixed toner A 100 parts and 1.0 part of small particle size hydrophobic silica particles (external additive, trade name: RX-200, manufactured by Nippon Aerosil Co., Ltd., average primary particle size 12 nm) (Trade name: FM20C, manufactured by Mitsui Mining Co., Ltd.) and stirred for 3 minutes at a peripheral speed of 20 m / sec on the outermost periphery of the stirring blade, to obtain toner A of Example 1.

(Example 2)
In the cross-linked resin fine particle fixing step S3, the toner of Example 2 (occupation ratio of cross-linked resin fine particles on the toner surface: 14.1) is changed in the same manner as in Example 1 except that the spraying time of the spray liquid A is changed from 15 minutes to 25 minutes. %).

(Example 3)
In the spray liquid preparation step S2, melamine particles having an average primary particle size of 0.1 μm are used in place of melamine particles having an average primary particle size of 0.2 μm, and the spray time of the spray liquid A is changed from 15 minutes in the crosslinked resin fine particle fixing step S3. A toner of Example 3 (occupation ratio of crosslinked resin fine particles on the toner surface of 8.3%) was obtained in the same manner as in Example 1 except that the time was changed to 10 minutes.

Example 4
In the spray liquid preparation step S2, melamine particles having an average primary particle size of 2.0 μm are used instead of melamine particles having an average primary particle size of 0.2 μm, and the spray time of the spray liquid A is changed from 15 minutes in the crosslinked resin fine particle fixing step S3. A toner of Example 4 (occupation ratio of crosslinked resin fine particles on the toner surface of 8.2%) was obtained in the same manner as in Example 1 except that the time was changed to 25 minutes.

(Example 5)
In the spray liquid preparation step S2, melamine particles having an average primary particle size of 0.08 μm are used instead of melamine particles having an average primary particle size of 0.2 μm, and the spray time of the spray liquid A is changed from 15 minutes in the crosslinked resin fine particle fixing step S3. The toner of Example 5 (occupation ratio of crosslinked resin fine particles on the toner surface: 8.3%) was obtained in the same manner as in Example 1 except that the time was changed to 7 minutes.

(Example 6)
In the spray liquid preparation step S2, melamine particles having an average primary particle size of 2.2 μm are used instead of melamine particles having an average primary particle size of 0.2 μm, and the spray time of the spray liquid A is changed from 15 minutes in the crosslinked resin fine particle fixing step S3. A toner of Example 6 (occupation ratio of crosslinked resin fine particles on the toner surface of 8.2%) was obtained in the same manner as in Example 1 except that the time was changed to 35 minutes.

(Example 7)
In the cross-linked resin fine particle fixing step S3, the toner of Example 7 (occupation ratio of cross-linked resin fine particles on the toner surface of 0.08 is the same as in Example 1 except that the spraying time of the spray liquid A is changed from 15 minutes to 5 minutes. %).

(Example 8)
In the crosslinked resin fine particle fixing step S3, the toner of Example 8 (occupation ratio of the crosslinked resin fine particles on the toner surface of 15.9) is the same as that of Example 1 except that the spraying time of the spray liquid A is changed from 15 minutes to 30 minutes. %).

Example 9
The toner of Example 9 is the same as Example 1 except that, in the spray liquid preparation step S2, crosslinked acrylic particles having an average primary particle size of 0.2 μm are used instead of melamine particles having an average primary particle size of 0.2 μm. (The occupation ratio of the crosslinked resin fine particles on the toner surface was 8.4%).

(Example 10)
In the crosslinked resin fine particle fixing step S3, the toner of Example 10 (occupation ratio of crosslinked resin fine particles on the toner surface 5.1) is the same as that of Example 1 except that the spraying time of the spray liquid A is changed from 15 minutes to 10 minutes. %).

(Example 11)
In the crosslinked resin fine particle fixing step S3, the toner of Example 11 (occupation ratio of the crosslinked resin fine particles on the toner surface 12.1) was changed in the same manner as in Example 1 except that the spraying time of the spray liquid A was changed from 15 minutes to 20 minutes. %).

(Example 12)
In the spray liquid preparation step S2, melamine particles having an average primary particle size of 1.0 μm are used instead of melamine particles having an average primary particle size of 0.2 μm, and the spray time of the spray liquid A is changed from 15 minutes in the crosslinked resin fine particle fixing step S3. A toner of Example 12 (occupation ratio of crosslinked resin fine particles on the toner surface of 8.5%) was obtained in the same manner as in Example 1 except that the time was changed to 30 minutes.

(Comparative Example 1)
100 parts of toner base particles A produced in the same manner as in Example 1 and 1.0 part of melamine particles having an average primary particle size of 0.2 μm were charged into a Henschel mixer (trade name: FM20C, manufactured by Mitsui Mining Co., Ltd.) Stirring was performed at a peripheral speed of 20 m / sec at the outermost periphery of the stirring blade for 3 minutes to obtain a toner of Comparative Example 1 (occupation ratio of crosslinked resin fine particles on the toner surface of 8.2%).

(Comparative Example 2)
In the spray liquid preparation step S2, in the same manner as in Example 1 except that non-crosslinked acrylic particles having an average primary particle size of 0.2 μm were used instead of melamine particles having an average primary particle size of 0.2 μm, Comparative Example 2 A toner (occupation ratio of crosslinked resin fine particles on the toner surface of 8.0%) was obtained.

(Comparative Example 3)
In the spray liquid preparation step S2, the toner of Comparative Example 3 was prepared in the same manner as in Example 1 except that silica particles having an average primary particle size of 0.2 μm were used instead of melamine particles having an average primary particle size of 0.2 μm. Resin fine particle occupation ratio on the toner surface was 8.4%).

  The obtained toners of Examples 1 to 12 and Comparative Examples 1 to 3 were evaluated by the following methods. As an image forming apparatus for evaluation, a digital full-color multifunction peripheral (trade name: AR-C260, manufactured by Sharp Corporation, non-magnetic one-component developing method; using a metal regulating blade) was used, and a printing test of 20k sheets was performed.

[Toner aggregation resistance]
After the printing test of 20k sheets, the white streaks of the image and the presence or absence of toner fusion on the regulating blade were observed and evaluated according to the following criteria.
◎ (good): no white streaks on the image and no toner fusion ○ (possible): no white streaks on the image but very little toner fusion × (defect): white on the image There are streaks and toner fusing

[Cover]
The toners obtained in Examples 1 to 12 and Comparative Examples 1 to 3 were set in the image forming apparatus, and the density was measured using a Macbeth reflection densitometer on non-image portions before and after printing 20 k sheets. The fog density was calculated as follows and the fog was evaluated.
Fog density = (density of non-image area after printing) − (density of non-image area before printing)
◎ (good): fog density is 0.005 or less ○ (possible): fog density is more than 0.005 and less than 0.010 x (defect): fog density is 0.010 or more

[Fixability]
The toners obtained in Examples 1 to 12 and Comparative Examples 1 to 3 were set in the image forming apparatus, and a solid image having a side of 2 cm was printed with a toner adhesion amount of 0.4 mg / cm ² . . The surface of the solid image was rubbed 3 times with a Gakushin fastness tester (sand eraser with a weight of 1 kg), and the image density was measured using a Macbeth reflection densitometer for the images before and after the friction. The fixing rate was calculated as follows to evaluate the fixing property.
Fixing rate (%) = (image density after friction / image density before friction) × 100
◎ (good): fixing rate of 85% or more ○ (possible): fixing rate of 75% or more and less than 85% × (poor): fixing rate of less than 75% The toners of Examples 1 to 12 and Comparative Examples 1 to 3 Table 1 shows the evaluation results of each toner.

  The evaluation results of the toners of Examples 1 to 12 were good or acceptable. The toners of Comparative Examples 1 to 3 had good fixability, but the toner aggregation resistance and fog evaluation were poor. This is because in the toner of Comparative Example 1, the crosslinked resin fine particles were added without being dispersed in ethanol, and it is considered that the toners of Comparative Examples 2 and 3 did not use the crosslinked resin fine particles. .

DESCRIPTION OF SYMBOLS 201 Toner manufacturing apparatus 202 Powder flow path 203 Spraying means 204 Rotating stirring means 206 Powder input part 207 Powder recovery part 220 Stirring blade

Claims (4)

By spraying a spray liquid, in which crosslinked resin fine particles are dispersed in a volatile liquid by applying ultrasonic vibration, onto the toner base particles in a fluid state in the powder flow path, the surface of the toner base particles is cross-linked. A spraying step in which fine particles are adhered to form a crosslinked resin fine particle-adhered toner;
And a cross-linked resin fine particle fixing step of applying a shock to the cross-linked resin fine particle-adhered toner to fix the cross-linked resin fine particles on the surface of the toner base particles to form a cross-linked resin fine particle-fixed toner. Toner manufacturing method.   2. The cross-linked resin fine particle fixing step, wherein the impact is applied to the cross-linked resin fine particle-adhered toner using a rotary stirring unit including a rotary shaft and rotary blades provided radially on the rotary shaft. 2. A method for producing a toner for a one-component developer according to 1. In the spraying step, a spray liquid reservoir that stores the spray liquid, a nozzle that supplies the spray liquid into a powder flow path, a liquid feed pump that supplies a predetermined amount of the spray liquid to the nozzle, Spraying the spray liquid using a spray means comprising an ultrasonic vibrator for applying ultrasonic vibration to the spray liquid,
3. The one-component developer according to claim 1, wherein the spray liquid storage unit includes a stirring unit, and the spray liquid is stored in the spray liquid storage unit in a state of being stirred by the stirring unit. Of manufacturing toner.   The method for producing a toner for a one-component developer according to any one of claims 1 to 3, wherein the crosslinked resin fine particles are melamine resin particles.

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