JP2016129868A - Powder treatment device, method for producing capsule toner and capsule toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a powder treatment device which can melt only the surface of a powder particle without forming the powder particle into a spherical shape.SOLUTION: A powder treatment device 201 comprises a powder channel 202 for flowing a powder particle dispersed and floating in a gas, agitation means 204 for agitating the powder particle in a gas atmosphere, and heating means for bringing the powder particle dispersed and floating in the gas into contact with a heat component.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a powder processing apparatus, a capsule toner manufacturing method, and a capsule toner, and more particularly to a powder processing apparatus capable of melting only the surface of powder particles without making the powder particles spherical. It is.

  In an image forming apparatus using an electrophotographic method, there is a method of performing low-temperature fixing using a toner containing a binder resin having a low softening temperature. By performing the low-temperature fixing, the power supplied to the fixing device can be suppressed. However, a toner containing a binder resin having a low softening temperature is easily fused by heat, and the blocking resistance is lowered.

  The surface of toner base particles containing a binder resin having a low softening temperature is coated with resin fine particles having a higher softening temperature and higher heat resistance than the toner base particles to produce a capsule toner. There is a method for improving the blocking resistance without impairing the properties.

  Examples of a method for producing a capsule toner in which resin fine particles are coated on the surface of toner base particles as described above include, for example, a method in which resin fine particles are attached to the surface of toner base particles in an aqueous medium and heated, and a resin on the surface of toner base particles. A method for applying mechanical impact force by adhering fine particles, a method for adhering resin fine particles to the surface of toner base particles and heating in a high temperature air flow of 300 ° C. or more, and a method of spraying resin fine particle emulsion while stirring toner base particles Etc. are known.

  For example, Patent Document 1 discloses that a coating layer composed of resin fine particles having a high softening temperature is formed by applying a mechanical impact force after coating resin fine particles having a high softening temperature on the surface of toner base particles having a low softening temperature ( There is disclosed a toner in which resin fine particles are fixedly coated) to improve low-temperature fixability and blocking resistance. Patent Document 2 discloses a toner in which resin fine particles are fixed to the surface of a core particle by a mechanical impact force, and a non-offset property is improved with low power consumption as well as an improvement of a fixing method.

Japanese Patent No. 2838410 JP-A-2-163754

  However, the conventional method for producing a resin fine particle-coated toner has a problem that the toner becomes spheroidized due to excessively long heating time or excessive heat generation due to impact, and the cleaning property is lowered. On the other hand, when the heating time is shortened or the mechanical impact force is reduced in the conventional method for producing resin fine particle-coated toner, the resin fine particles are not sufficiently fused (formed into a film), and the resin from the toner There was a problem that the fine particles peeled off and adhered (fused) to the surface of the developing roller. For this reason, a novel method for producing a resin fine particle-coated toner and a novel powder processing apparatus that can be used in the production method are desired.

  Accordingly, an object of the present invention is to solve the above-mentioned problems of the prior art and provide a powder processing apparatus capable of melting only the surface of the powder particles without making the powder particles spherical. Another object of the present invention is to provide a capsule toner manufacturing method capable of suppressing the spheroidization of the capsule toner, and a capsule toner excellent in cleaning properties.

  The present inventor has intensively studied to achieve the above object, and by contacting the heating component with the powder particles dispersed and suspended in the gas, the powder particles are formed without making the powder particles spherical. The present inventors have found that only the surface can be melted and have completed the present invention.

  That is, the powder processing apparatus of the present invention includes a powder flow path for flowing powder particles dispersed and suspended in gas, a stirring means for stirring powder particles in a gas atmosphere, And a heating means for bringing the heating component into contact with the powder particles dispersed and suspended in.

  In a preferred example of the powder processing apparatus of the present invention, a cooling means for bringing a cooling component into contact with the powder particles dispersed and suspended in the gas is further provided.

Further, the method for producing the capsule toner of the present invention includes:
By stirring the toner base particles having a circularity of 0.96 or less and the resin fine particles having a volume average particle diameter of 0.1 μm or more and 0.5 μm or less in a gas atmosphere, the resin fine particles adhere to the surface of the toner base particles. A composite powder particle forming step for forming composite powder particles;
A heating component step in which a heating component is brought into contact with the composite powder particle to melt and form a resin fine particle on the surface of the toner base particle in a system in which the composite powder particle is dispersed and suspended in a gas. It is characterized by.

  The preferred embodiment of the capsule toner manufacturing method of the present invention further includes a cooling component step in which the cooling component is brought into contact with the composite powder particles obtained by the heating component step.

  In another preferred embodiment of the method for producing a capsule toner of the present invention, the heating component contains air or water vapor, and the temperature of the heating component is 30 ° C. or higher and lower than the glass transition temperature of the resin fine particles.

  The capsule toner of the present invention is a capsule toner comprising toner base particles and a coating layer formed on the surface of the toner base particles, and the capsule toner has a circularity of 0.96 or less. The surface arithmetic average height is 0.1 μm or more and 0.5 μm or less.

  According to the powder processing apparatus of the present invention, it is possible to provide a powder processing apparatus capable of melting only the surface of the powder particles without making the powder particles spherical. Further, according to the capsule toner manufacturing method of the present invention, it is possible to provide a capsule toner manufacturing method capable of suppressing the spheroidization of the capsule toner. Furthermore, according to the capsule toner of the present invention, it is possible to provide a capsule toner having excellent cleaning properties.

It is a front view which shows the structure of the powder processing apparatus 201 which is one embodiment of the powder processing apparatus of this invention. It is a schematic sectional drawing by the A-A 'line of the powder processing apparatus 201 shown in FIG. It is a schematic sectional drawing of the powder processing apparatus which is the other embodiment of the powder processing apparatus of this invention. It is a schematic sectional drawing of the powder processing apparatus which is the other embodiment of the powder processing apparatus of this invention. It is a schematic sectional drawing by the B-B 'line of the powder processing apparatus shown in FIG. It is a schematic sectional drawing of the powder processing apparatus which is the other embodiment of the powder processing apparatus of this invention. It is a flowchart which shows one embodiment of the manufacturing method of the capsule toner of this invention.

<Powder processing equipment>
Hereinafter, the powder processing apparatus of the present invention will be described in detail with reference to the drawings. FIG. 1 is a front view showing a configuration of a powder processing apparatus 201 which is one embodiment (hereinafter also referred to as a first embodiment) of the powder processing apparatus of the present invention. FIG. 2 is a schematic cross-sectional view taken along the line AA ′ of the powder processing apparatus 201 shown in FIG. The illustrated powder processing apparatus 201 includes a powder flow path 202 for flowing powder particles dispersed and suspended in gas, a stirring means 204 for stirring powder particles in a gas atmosphere, and a gas Heating means (jet nozzle 203a and / or temperature adjusting jacket 203c) for bringing the heating component into contact with the powder particles dispersed and suspended therein is provided. Further, in the illustrated powder processing apparatus 201, the powder flow path 202 constitutes a circulation means so that the powder particles dispersed and suspended in the gas can be circulated. As shown in FIGS. 1 and 2, the powder processing apparatus of the present invention is provided with cooling means (jet nozzle 203b and / or for bringing a cooling component into contact with powder particles dispersed and suspended in a gas. A temperature adjustment jacket 203c), a powder charging unit 206, and a powder recovery unit 207 may be provided. The heating means for contacting the heating component and the cooling means for contacting the cooling component may use the injection nozzles 203a and 203b, or may use the temperature adjustment jacket 203c provided on the wall surface of the apparatus. Both the injection nozzles 203a and 203b and the temperature adjustment jacket 203c may be used.

(Powder channel)
In the illustrated powder processing apparatus 201, the powder channel 202 is a channel through which powder particles dispersed and suspended in a gas flow, and the powder particles can circulate in the powder channel. It is configured as follows. By providing such a powder flow path 202, the surface of the powder particles can be reliably melted. The powder channel 202 includes an agitation unit 208 that accommodates the agitation means 204 and a powder flow part 209 through which the powder fluid dispersed and suspended in the gas flows. The stirring unit 208 is a cylindrical container-like member having an internal space, and is also referred to as a rotary stirring chamber. In addition, openings 210 and 211 are formed in the stirring unit 208. 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 of the stirring unit 208 positioned in the axial direction of the stirring unit 204. Further, the opening 211 is formed so as to penetrate the side wall including the side surface 208b of the stirring unit 208 in the thickness direction on the side surface 208b perpendicular to the surface 208a of the stirring unit 208 positioned in the axial direction of the stirring unit 204. The powder flow part 209 is a circulation pipe through which powder particles can circulate via the stirring part 208, and one end of the pipe is connected to the opening part 210 and the other end is connected to the opening part 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 powder particles dispersed and suspended in the gas flow through the powder channel 202. The powder flow path 202 is provided such that the powder flow direction 214, which is the direction in which the powder particles flow, is a constant direction. A powder flow path interior 250 is formed from the inside of the agitation part and the powder flow part.

  In the illustrated powder processing apparatus 201, the powder particles are not particularly limited, but from the viewpoint of using the powder processing apparatus 201 in a capsule toner manufacturing method, the powder particles are described below. Preferred examples include toner base particles, resin fine particles, and composite powder particles formed of these. The gas for dispersing and floating the powder particles is not particularly limited, and examples thereof include air and nitrogen. As the gas for dispersing and floating the powder particles, the gas present in the powder flow path 202 may be normally used. For example, the powder can be obtained by connecting a gas supply means (not shown) to the powder flow path. It is also possible to supply during operation of the processing device. Moreover, the gas injected by the injection nozzle described later also constitutes a part of the gas for dispersing and floating the powder particles. The temperature of the gas in the powder processing apparatus before the powder particles are dispersed and suspended is preferably 0 ° C. or higher and lower than 30 ° C. In the powder processing apparatus of the present invention, the temperature of the gas in which the powder particles are dispersed and suspended is preferably measured in a circulation pipe in which the powder particles, gas, and the like flow and circulate. In the powder processing apparatus 201, the temperature of the gas flowing in the vicinity of the opening 210 is set as the temperature of the gas in which the powder particles are dispersed and suspended.

  During operation of the powder processing apparatus 201 in the illustrated example, the powder particles dispersed and suspended in the gas flow in the powder flow direction 214 in the powder flow path. For example, rotary stirring by the stirring means 204 is used. Then, powder particles can be flowed.

(Stirring means)
In the powder processing apparatus 201 of the illustrated example, the stirring unit 204 is a unit for stirring the powder particles in a gas atmosphere. As described above, the powder particles dispersed and suspended in the gas are powdered. It can also be used when flowing into the body flow path 202. Further, when the powder particles include toner mother particles and resin fine particles as described later, the toner mother particles and the resin fine particles are agitated in a gas atmosphere so that the resin fine particles are attached to the surface of the toner mother particles. Body particles can be formed. Here, the stirring means used in the powder processing apparatus of the present invention is housed in a cylindrical container-like member (so-called stator) having an internal space. Here, the container-like member (in FIGS. The unit 208) is installed so as to be spaced from the inner wall. By keeping the distance from the inner wall wide in this way, melting of the surface of the powder particles, for example, melting of the resin fine particles and film formation is prevented. On the other hand, in the method of producing a resin fine particle-coated toner by a method of applying a mechanical impact force, in general, the mechanical impact force is applied to the powder particles by the stirring blades with the space between the inner wall being narrowed. The degree of deformation of the body particles is large, and melting of the surface of the powder particles occurs.

  The stirring means 204 includes a rotating shaft member 218, a disk-shaped rotating disk 219, and a plurality of stirring blades 220. The rotary shaft member 218 has an axial line that coincides with the axial direction of the stirring means and is formed in a surface 208c that faces the surface 208a of the stirring unit 208 so as to penetrate a side wall including the surface 208c in the thickness direction. A cylindrical rod-like member provided so as to be inserted through 221 and rotated about 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 with the rotation of the rotating shaft member 218. The plurality of stirring blades 220 are supported by the peripheral portion of the turntable 219 and rotate as the turntable 219 rotates.

  The stirring means 204 can rotate at a peripheral speed of 100 m / sec or less at the outermost periphery, but the peripheral speed at the outermost periphery is preferably 30 m / sec or more and 80 m / sec or less. The outermost periphery is a portion of the stirring means 204 having the longest distance from the rotation shaft member 218 in the direction perpendicular to the rotation shaft member 218. The through-hole 221 connects the powder flow channel inside 250 and the powder flow channel outside, and through the through-hole 221, a gas for dispersing and floating the powder particles and a component sprayed from the spray nozzle are present. The powder is discharged from the inside of the powder passage 250 to the outside of the powder passage.

(Heating means)
In the illustrated powder processing apparatus 201, the heating means is a means for bringing the heating component into contact with the powder particles dispersed and suspended in the gas. By bringing the heating component into contact with the powder particles, only the surface of the powder particles can be melted without making the powder particles spherical. Here, when the powder particles include toner base particles and resin fine particles, and the resin fine particles are adhered to the surface of the toner base particles by the above-described stirring means, only the resin fine particles can be melted, and the spherical shape of the capsule toner The coating layer formed by fusing the resin fine particles can be firmly adhered to the surface of the toner base particles while suppressing the formation.

  Examples of the heating means include an injection nozzle 203a and a temperature adjustment jacket 203c. By connecting to the powder channel 202, the heating component can be brought into contact with the powder particles flowing in the powder channel interior 250. it can. In the illustrated powder processing apparatus 201, the injection nozzle 203a is installed in the powder flow section 209 of the powder flow path 202. However, in the powder processing apparatus of the present invention, the present invention is not limited to this. You may install in the stirring part of a flow path. Although the powder processing apparatus 201 in the illustrated example includes the spray nozzle 203a and the temperature adjustment jacket 203c as heating means, the powder processing apparatus of the present invention is not limited to this, and only the temperature adjustment jacket 203c is provided. You may provide as a heating means.

  The heating component preferably contains air or water vapor, and these are preferably used as a medium. Further, the temperature of the heating component is preferably 30 ° C. or higher. However, for example, when the powder particles include toner base particles and resin fine particles, the temperature is preferably equal to or lower than the glass transition temperature of the resin fine particles.

(Cooling means)
In the powder processing apparatus 201 of the illustrated example, the cooling means is means for bringing the cooling component into contact with the powder particles dispersed and suspended in the gas. When the surface of the powder particles is melted by the heating means, the powder particles may aggregate. For this reason, it is preferable to cool the powder particles after the surface of the powder particles has melted.

  Examples of the cooling means include an injection nozzle 203b, a temperature adjusting jacket 203c, and the like. By connecting to the powder channel 202, a cooling component can be brought into contact with the powder particles flowing in the powder channel interior 250. it can. In the illustrated powder processing apparatus 201, the injection nozzle 203b is installed in the powder flow section 209 of the powder flow path 202. However, in the powder processing apparatus of the present invention, the present invention is not limited to this. You may install in the stirring part of a flow path. In the case where the powder processing apparatus of the present invention includes an injection nozzle as a heating unit and a cooling unit, the injection nozzle 203b is connected to the powder flow path 202 at a position downstream of the injection nozzle 203a in the powder flow direction 214. Preferably, it is a position on the downstream side of the injection nozzle 203a, but it is more preferable to be connected to a position on the upstream side of the stirring means 204. Thereby, the cooling component can be more effectively sprayed on the powder particles that have been sprayed with the heating component. Furthermore, the powder processing apparatus of the present invention may include a plurality of injection nozzles. By providing a plurality of injection nozzles, the processing temperature of the powder can be precisely controlled, and a homogeneous encapsulated toner can be produced. The powder processing apparatus 201 in the illustrated example includes the injection nozzle 203b and the temperature adjustment jacket 203c as cooling means. However, the powder processing apparatus of the present invention is not limited to this, and only the temperature adjustment jacket 203c is provided. You may provide as a cooling means.

  The cooling component preferably includes air. Moreover, it is preferable that the temperature of a cooling component is 0 degreeC or more and less than 30 degreeC.

(Temperature adjustment jacket)
The powder processing apparatus of the present invention preferably includes a temperature adjustment jacket 203c. The temperature adjusting jacket 203c can be used as a heating means and a cooling means as described above. For example, if a heating medium is passed through the space inside the jacket, it can be used as a heating means, and if a cooling medium is passed through the space inside the jacket, it can be used as a cooling means. The temperature adjusting jacket 203c is provided on at least a part of the outside of the powder channel 202, and adjusts the temperature of the powder channel interior 250 through a cooling medium or a heating medium in the space inside the jacket. The temperature adjusting jacket 203c is preferably provided in the entire outside region of the powder channel 202.

(Powder input part and powder recovery part)
The powder processing apparatus of the present invention includes a powder input unit 206 for supplying powder particles to the powder channel, and a powder recovery unit 207 for recovering the powder particles from the powder channel. It is preferable. In the illustrated powder processing apparatus 201, a powder input unit 206 and a powder recovery unit 207 are connected to the powder flow unit 209 of the powder channel 202. The powder input unit 206 includes a hopper (not shown) that supplies powder 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 powder 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 powder particles supplied to the powder flow path 202 flow in a constant powder flow direction by stirring by the stirring means 204. Further, when the flow path in the supply pipe 212 is closed by the electromagnetic valve 213, the powder 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 powder 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 powder flowing through the powder flow path 202 is not collected.

  FIG. 3 is a schematic cross-sectional view of a powder processing apparatus which is another embodiment (hereinafter also referred to as a second embodiment) of the powder processing apparatus of the present invention. The powder processing apparatus shown in FIG. Compared with the powder processing apparatus shown in FIG. 2, it is characterized by including a cyclone connected to the powder flow section of the powder flow path via the discharge path and the recovery path. The cyclone is a device in which gas flows in a vortex, and includes an exhaust port for exhausting at the upper part and an exhaust port for recovering powder particles at the lower part, as shown in FIG. For this reason, by providing a cyclone, even if the flow rate of the cooling component per unit time is increased, the powder particles can be prevented from being discharged together with the exhaust gas, and the powder particles can be effectively recovered. it can. The powder particles recovered by the cyclone are sent from the discharge port at the lower part of the cyclone to the recovery path and returned to the powder flow part again. The discharge port at the lower part of the cyclone is provided with a discharge member for discharging powder particles while suppressing the inflow of gas toward the inside of the cyclone, and a butterfly valve or the like can be used as the discharge member. In the powder processing apparatus of FIG. 3 as well, it is preferable to provide a temperature adjusting jacket as in FIG. The temperature adjusting jacket can be used as a heating means and a cooling means. For example, if a heating medium is passed through the space inside the jacket, it can be used as a heating means, and if a cooling medium is passed through the space inside the jacket, it can be used as a cooling means.

  FIG. 4 is a schematic cross-sectional view of a powder processing apparatus which is another embodiment (hereinafter also referred to as a third embodiment) of the powder processing apparatus of the present invention. FIG. 5 is a schematic sectional view taken along line B-B ′ of the powder processing apparatus shown in FIG. 4. In the powder processing apparatus shown in FIGS. 4 and 5, the powder flow path is composed only of a stirring unit that accommodates the rotating means, where the stirring unit includes a cylindrical stirring tank having a bottomed cylindrical shape, The upper part of this cylindrical stirring tank is comprised from the disk-shaped opening-and-closing type upper cover which can be opened and closed freely. The powder particles are rotationally fluidized in the stirring unit while being dispersed and suspended in the gas by the stirring means. For this reason, an injection nozzle is provided as a heating means and a cooling means on the side wall of the cylindrical stirring tank, and a temperature adjusting jacket is provided as a heating means and a cooling means over the entire outside of the stirring portion. The stirring means includes a rotating shaft member provided so as to be inserted into a through hole in the bottom wall of the cylindrical stirring tank, and a substantially rectangular stirring blade extending in the horizontal direction from the rotating shaft member. 4 and 5, the powder processing apparatus shown in FIGS. 4 and 5 includes a cyclone. As shown in FIG. 4, the discharge port at the lower part of the cyclone has a disk-like opening and closing. It is directly connected to the upper lid. Also in the powder processing apparatus of FIG. 4, it is preferable to provide a temperature adjustment jacket as in FIGS. The temperature adjusting jacket can be used as a heating means and a cooling means. For example, if a heating medium is passed through the space inside the jacket, it can be used as a heating means, and if a cooling medium is passed through the space inside the jacket, it can be used as a cooling means. In that case, the spray nozzle may or may not be used together as the heating means and the cooling means.

  FIG. 6 is a schematic cross-sectional view of a powder processing apparatus which is another embodiment (hereinafter also referred to as a fourth embodiment) of the powder processing apparatus of the present invention. The powder processing apparatus shown in FIG. 6 is a modification of the third embodiment, and includes a cooling component introduction path in place of the injection nozzle as the cooling means in the third embodiment. The cooling component introduction path is provided so that the cooling component can be introduced from the gap between the through hole in the bottom wall of the cylindrical stirring tank and the rotary shaft member. As a result, the powder particles leak from the gap between the through hole and the rotary shaft member due to gravity, or the powder particles are melted by the frictional heat between the rotary shaft member and the seal member (not shown) provided in the through hole and the rotary shaft member. Wearing can be prevented. Also in the powder processing apparatus of FIG. 6, it is preferable to provide a temperature adjusting jacket as in FIGS. The temperature adjusting jacket can be used as a heating means and a cooling means. For example, if a heating medium is passed through the space inside the jacket, it can be used as a heating means, and if a cooling medium is passed through the space inside the jacket, it can be used as a cooling means.

<Method for producing capsule toner>
Next, the manufacturing method of the capsule toner of the present invention will be described in detail with reference to the drawings. In the method for producing the capsule toner of the present invention, the toner base particles having a circularity of 0.96 or less and the resin fine particles having a volume average particle size of 0.1 μm or more and 0.5 μm or less are stirred in a gas atmosphere, In a composite powder particle forming step for forming composite powder particles in which resin fine particles are adhered to the surface of the toner base particles, and in a system in which the composite powder particles are dispersed and suspended in a gas, a heating component is added to the composite powder particles. And a heating component step of melting the resin fine particles on the surface of the toner base particles to form a film. In the case of the capsule toner of the present invention, the composite powder particles are formed without bringing the composite powder particles into a spherical shape by bringing the heating component into contact with the composite powder particles having resin fine particles attached to the surface of the toner base particles. Only the resin fine particles, that is, the resin fine particles can be melted, and a coating layer formed by forming the resin fine particles into a film can be effectively produced. Therefore, by using toner base particles having a circularity of 0.96 or less and resin fine particles having a volume average particle size of 0.1 μm or more and 0.5 μm or less, the capsule toner of the present invention as described later is manufactured. be able to.

  The capsule toner manufacturing method of the present invention is preferably performed by using the above-described powder processing apparatus of the present invention. In this case, the composite powder particle forming step is performed by using a stirring unit, and the heating component step is performed by using a heating unit.

  FIG. 7 is a flowchart showing an embodiment (hereinafter also referred to as a fifth embodiment) of the capsule toner manufacturing method of the present invention. The capsule toner manufacturing method of the illustrated example includes a toner base particle preparation step S1 for preparing toner base particles, a resin fine particle preparation step S2 for preparing resin fine particles, and a film formed by coating the toner base particles with resin fine particles. Conversion step S3. Here, the film forming step S3 includes a temperature adjusting step, a cooling component step, and a recovery step in addition to the composite powder particle forming step and the heating component step described above.

(1) Toner mother particle production step S1
In the toner base particle preparation step, toner base particles that become the core of the capsule toner and whose surface is coated with resin fine 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 obtained 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.

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

  Known mixers can be used. For example, Henschel mixer (trade name, manufactured by Nippon Coke Industries Co., Ltd.), super mixer (trade name, manufactured by Kawata Co., Ltd.), Mechano Mill (trade name, manufactured by Okada Seiko Co., Ltd.) Henschel type mixing devices such as HONSHELL type, ANGMILL (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.), etc. .

  A well-known thing can be used also as a kneading machine, for example, common kneading machines, such as a twin-screw extruder, a 3 roll, a laboratory 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 Nihon Coke Kogyo Co., Ltd.) and other open roll type kneaders.

  The kneaded product is cooled and solidified, and then coarsely pulverized into a coarsely pulverized product having a weight average particle size of 100 μm or more and 5 mm or less by a hammer mill or a cutting mill, and the obtained coarsely pulverized product has a weight average particle size of 15 μm, for example. Further pulverized to: For finely pulverizing the coarsely pulverized product, for example, a jet pulverizer using a supersonic jet stream, or a coarsely pulverized product in a space formed between a rotor (rotor) rotating at high speed and a stator (liner) An impact type pulverizer or the like that pulverizes by introduction of the above 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 swirl wind classifier (rotary wind classifier) or the like is used. be able to.

(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, polystyrene, styrene monomer and (meth) acrylic acid monomer and / or Examples include styrene-acrylic resins copolymerized with (meth) acrylic acid ester monomers, (meth) acrylic acid ester 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.

  The monomer constituting the styrene-based resin preferably contains a styrene monomer as an essential monomer and, if necessary, a (meth) acryl monomer and / or a carboxyl group-containing vinyl monomer. Here, the styrene resin means a homopolymer of a styrene monomer or a copolymer of a styrene monomer and another monomer. Moreover, (meth) acryl means acryl and / or methacryl. Examples of the styrene monomer include styrene and alkyl styrene having an alkyl group having 1 to 3 carbon atoms (for example, α-methyl styrene, p-methyl styrene) and the like. Styrene is preferred. Examples of (meth) acrylic monomers include alkyl groups such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, and stearyl (meth) acrylate. C1-C18 alkyl (meth) acrylate; Hydroxyethyl (meth) acrylate etc. Alkyl group C1-C18 hydroxylalkyl (meth) acrylate; Dimethylaminoethyl (meth) acrylate, Diethylaminoethyl (meth) Examples thereof include alkylamino group-containing (meth) acrylates having 1 to 18 carbon atoms in the alkyl group such as acrylate; nitrile group-containing vinyl monomers such as acrylonitrile and methacrylonitrile. Examples of the carboxyl group-containing vinyl monomer include monocarboxylic acids [having 3 to 15 carbon atoms such as (meth) acrylic acid, crotonic acid and cinnamic acid], dicarboxylic acids [having 4 to 15 carbon atoms such as (anhydrous) maleic acid and fumaric acid. , Itaconic acid, citraconic acid], dicarboxylic acid monoester [monoalkyl (carbon number 1 to 18) ester of the above dicarboxylic acid, such as maleic acid monoalkyl ester, fumaric acid monoalkyl ester, itaconic acid monoalkyl ester, citraconic acid monoester Alkyl ester] and the like. Among these (meth) acrylic monomers and carboxyl group-containing vinyl monomers, alkyl (meth) acrylates having 1 to 18 carbon atoms, acrylonitrile, methacrylonitrile, (meth) acrylic acid, dicarboxylic acid monoesters, and two or more kinds thereof Mixtures are preferred.

  A known monomer can be used as the monomer constituting the polyester resin, and examples thereof include a polycondensate of a polybasic acid and a polyhydric alcohol.

  As the polybasic acid, those known as polyester monomers can be used. 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 polyhydric alcohols, those known as monomers for polyesters can be used. For example, aliphatic polyhydric alcohols such as ethylene glycol, propylene glycol, butanediol, hexanediol, neopentyl glycol, glycerin, cyclohexanediol, cyclohexanedi Examples include alicyclic polyhydric alcohols such as methanol and hydrogenated bisphenol A, aromatic diols such as an ethylene oxide adduct of bisphenol A, and a propylene oxide adduct 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, the polybasic acid and the polyhydric alcohol are contacted in the presence or absence of an organic solvent and in the presence of a polycondensation catalyst. The process is terminated when the acid value, softening temperature, and the like of the resulting polyester reach desired values. Thereby, polyester is obtained. 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, by appropriately changing the compounding ratio of polybasic acid and polyhydric alcohol, the reaction rate, etc., for example, the carboxyl group content at the end of the polyester can be adjusted, and thus the properties of the resulting polyester Can be denatured. Even when trimellitic anhydride is used as the polybasic acid, a carboxyl group can be easily introduced into the main chain of the polyester, thereby obtaining a modified polyester. A self-dispersible polyester in water 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 can also be used. Further, polyester and acrylic resin may be grafted.

  The binder resin preferably has a glass transition point of 30 ° C. or higher and 80 ° C. or lower. If the glass transition point of the binder resin is less than 30 ° C., blocking in which the toner thermally aggregates easily occurs in the image forming apparatus, and storage stability may be lowered. When the glass transition point 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.

  The binder resin preferably has a softening temperature of 80 ° C. or higher and 150 ° C. or lower. Furthermore, the binder resin preferably has an acid value of 0 KOHmg / g or more and 30 KOHmg / g or less.

  As the colorant, organic dyes, organic pigments, inorganic dyes, inorganic pigments and the like commonly used in the electrophotographic field can be used. Although the usage-amount of a coloring agent is not restrict | limited in particular, Preferably it is 5 mass parts or more and 10 mass parts or less with respect to 100 mass parts of binder resin.

  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. The amount of the charge control agent used is not particularly limited, but is preferably 0.1 parts by mass or more and 5 parts by mass or less with respect to 100 parts by mass 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, polyolefin polymer wax (low molecular weight polyethylene wax etc.) and derivatives thereof, hydrocarbon synthetic wax, carnauba wax and the like. The amount of the release agent used is not particularly limited, but is preferably 1 part by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the binder resin.

  The toner base particles obtained in the toner base particle preparation step S1 preferably have a volume average particle size of 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.

  The toner base particles obtained in the toner base particle preparation step S1 usually have a circularity of 0.96 or less, preferably 0.940 or more and 0.960 or less.

In the present invention, the circularity of the toner base particles and the circularity of the capsule toner described later can be measured using, for example, a flow type particle image analyzer “FPIA-3000” (manufactured by Malvern), but the measurement principle is the same. If it is, there will be no limitation in particular. The measuring principle of this apparatus is to take a still image of particles in a dispersion medium with a CCD camera and perform calculation such as circularity calculation from the image. The sample put in from the chamber is sent to the flat sheath flow cell and sandwiched between sheath liquids to form a flat flow. A still image is taken with a CCD camera while irradiating the sample passing through the cell with strobe light. The contour of each particle is extracted by image processing of the captured image, and the projected area S, the peripheral length L, and the like of the particle image are measured. From this, the equivalent circle diameter and circularity are calculated.
The equivalent circle diameter is the diameter of a circle having the same area as the projected area of the particle image, and the circularity is defined as the circumference of the circle calculated from the equivalent circle diameter divided by the circumference of the projected particle image. Is calculated by the following equation.
Circularity = 2 × (π × S) ^1/2 / L
As the sheath liquid, a particle sheath “PSE-900A” (manufactured by Malvern) is used, as a dispersant, a commercially available 5% by weight aqueous dispersion of household detergent, and as a disperser, the autosampler apparatus of the apparatus is used. Then, the sample is dispersed and introduced into the flow type particle image analyzer, and 10,000 toner mother particles or capsule toners are measured in a total count in the HPF measurement mode. Then, the binarization threshold at the time of particle analysis is set to 85%, and the average circularity of the toner base particles or the capsule toner is obtained as the total particle size range.

(2) Resin fine particle preparation step S2
In the resin fine particle preparation step, resin fine particles used for forming a layer covering the toner base particles are prepared. The resin fine particles are used as a material for forming a film on the surface of the toner base particles in the subsequent film forming step S3. By using the resin fine particles as a film forming material on the surface of the toner base particles, it is possible to prevent the occurrence of aggregation due to melting of a low melting point component such as a release agent contained in the toner base particles during storage.

  The resin fine particles can be obtained, for example, by an emulsion polymerization reaction of a monomer component that is a resin raw material, or can be obtained by emulsifying and dispersing a resin with a homogenizer or the like to make fine particles.

  As the resin used as the resin fine particle raw material, for example, a resin used for a toner material can be used. For example, polystyrene, styrene monomer, (meth) acrylic acid monomer and / or (meth) acrylic acid ester monomer can be used. Examples thereof include copolymerized styrene-acrylic resins, (meth) acrylic ester resins such as polymethyl methacrylate, and polyester resins. The resin fine particles preferably include a styrene-acrylic resin or a polyester resin among the resins exemplified above. Styrene-acrylic resins have many advantages such as light weight, high strength, high transparency, low cost, and easy to obtain materials with uniform particle diameters.

  The resin used as the resin fine particle raw material may be the same type of resin as the binder resin contained in the toner base particles or a different type of resin. Therefore, it is preferable to use a different type of resin. When a resin different from the binder resin contained in the toner mother particles is used as the resin used as the resin fine particle raw material, the softening temperature of the resin used as the resin fine particle raw material is the binder resin contained in the toner mother particles, or It is preferably higher than the softening temperature of the component contained in the toner base particles such as a release agent. As a result, the toner manufactured by the manufacturing method of the present embodiment can prevent the toners from fusing together during storage, and can improve storage stability. The softening temperature of the resin used as the resin fine particle raw material is preferably 80 ° C. or more and 140 ° C. or less, although it depends on the image forming apparatus in which the toner is used. By using a resin having a softening temperature in such a range, a toner having both storage stability and fixability can be obtained.

  The resin fine particles are required to have a volume average particle size sufficiently smaller than the average particle size of the toner base particles, and preferably 0.1 μm or more and 0.5 μm or less. When the volume average particle diameter of the resin fine particles is 0.1 μm or more and 0.5 μm or less, it is excellent in plasticity and easily deforms, and a uniform coating layer is formed on the surface of the toner base particles. The particle diameter of the resin fine particles represents a volume average particle diameter measured by a dynamic light scattering method.

  The resin fine particles preferably have a glass transition point of 50 ° C. or higher and 80 ° C. or lower. The resin fine particles preferably have a softening temperature of 80 ° C. or higher and 140 ° C. or lower.

(3) Film forming step S3
The film forming step S3 includes a temperature adjusting step S3a, a composite powder particle forming step S3b, a heating component step S3c, a cooling component step S3d, and a recovery step S4d. However, in the film forming step S3, the cooling component step S3d is an arbitrary step, and therefore the cooling component step S3d may not be adopted. As described above, the capsule toner manufacturing method of the present invention is preferably performed by using the above-described powder processing apparatus of the present invention. A powder processing apparatus will be used. Below, film-forming process S3 is demonstrated using the powder processing apparatus 201 shown in FIG.

(3-1) Temperature adjustment step S3a
The temperature adjustment step S3a is a step of adjusting the temperature of the heating component and the cooling component used for the heating unit and the cooling unit. For example, the spray nozzle 203a adjusts the temperature of the heating component brought into contact with the powder particles, and the jet nozzle 203b and the temperature adjustment jacket 203c adjust the temperature and jacket of the cooling component brought into contact with the powder particles. Adjust the supply temperature of the flowing medium.

(3-2) Composite powder particle forming step S3b
In the composite powder particle forming step, toner base particles having a circularity of 0.96 or less and resin fine particles having a volume average particle size of 0.1 μm or more and 0.5 μm or less are agitated in a gas atmosphere. This is a step of forming composite powder particles having resin fine particles attached to the particle surface.

  You may pre-mix with a commercially available mixer in advance. Known premixers at this time can be used, for example, Henschel mixer (trade name, manufactured by Nihon Coke Industries Co., Ltd.), super mixer (trade name, manufactured by Kawata Co., Ltd.), Mechano Mill (trade name, Okada Seiko). Henschel type mixing equipment such as Co., Ltd., Ongmill (trade name, manufactured by Hosokawa Micron Co., Ltd.), Hybridization system (trade name, manufactured by Nara Machinery Co., Ltd.), high speed vacuum dryer and dynamic dryer (trade name, Kawasaki) Heavy Industries, Ltd.).

  In the composite powder particle forming step, for example, the toner base particles and the resin fine particles are supplied to the powder flow path 202 from the powder input unit 206 in a state where the rotating shaft member 218 of the stirring unit 204 rotates. The toner base particles and the resin fine 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. As a result, the resin fine particles adhere to the surface of the toner base particles, and composite powder particles in which the resin fine particles adhere to the toner base particle surfaces are formed. In the capsule toner manufacturing method of the present invention, the mixing ratio of the resin fine particles to 100 parts by mass of the toner base particles is preferably 5 parts by mass or more and 10 parts by mass or less. In the method for producing a capsule toner of the present invention, the stirring time is preferably 1 minute or more and 60 minutes or less in order to more reliably form the composite powder particles.

  In the composite powder particle forming step, the temperature of the gas in which the powder particles are dispersed and suspended is preferably 0 ° C. or higher and lower than 30 ° C.

(3-3) Heating component process S3c
In the heating component step, in the system in which the composite powder particles obtained by the composite powder particle forming step are dispersed and suspended in the gas, the heating component is brought into contact with the composite powder particles, and the resin fine particles on the surface of the toner base particles Is a step of melting and forming a film. For example, the surface of the composite powder particle is brought into contact with the composite powder particles flowing in the aerosol form through the powder flow path 202 by the spray nozzle 203a which is a heating means and / or the temperature adjusting jacket 203c. Only the vicinity, that is, only the resin fine particles are heated and melted. Thereby, the resin fine particles are formed into a film (encapsulation), and a coating layer is formed on the surface of the toner base particles.

  The heating component preferably contains air or water vapor. Moreover, it is preferable that the temperature of a heating component is 30 degreeC or more and below the glass transition temperature of resin fine particles.

(3-4) Cooling component step S3d
The cooling component step is a step of bringing a cooling component into contact with the composite powder particles in order to prevent aggregation of the composite powder particles obtained by the heating component step. For example, the composite powder particles flowing in the form of aerosol through the powder flow path 202 are brought into contact with the cooling component by the spray nozzle 203b and / or the temperature adjusting jacket 203c as cooling means, and the composite powder particles are brought into contact with each other. Can be cooled. If the injection by the injection nozzle 203b and the injection by the injection nozzle 203a and / or the supply temperature of the medium flowing through the temperature adjustment jacket 203c can be continuously performed, the heating and melting in the vicinity of the surface of the composite powder particles can be performed. This is instantaneous and can reliably prevent the composite powder particles from being excessively melted. For this reason, it is preferable that cooling component process S3d is performed in parallel with heating component process S3c.

  The cooling component preferably includes at least air. Moreover, it is preferable that the temperature of a cooling component is 0 degreeC or more and less than 30 degreeC.

(3-5) Recovery step S3e
The recovery step is a step of recovering composite powder particles obtained through the heating component step, preferably composite powder particles obtained through the cooling component step. For example, the composite powder particles are collected in the collection tank 215 via the collection pipe 216 in a state where the flow path in the collection pipe 216 is opened by the electromagnetic valve 217. At the time of recovery, the injection by the injection nozzle 203a and the injection by the injection nozzle 203b are stopped, and after the recovery, the rotation of the stirring means 204 is stopped.

  The composite powder particles recovered through the film forming process as described above can be used as a capsule toner. In the agitation means 204, the peripheral speed at the outermost periphery is preferably set to 30 m / sec or more and more preferably 30 m / sec to 80 m / sec during the film forming step S3. When the peripheral speed at the outermost periphery of the stirring unit 204 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 and the resin fine particles cannot be isolatedly flowed, and the toner base particle surfaces cannot be uniformly coated with the resin fine particles. Moreover, when the peripheral speed in the outermost periphery exceeds 80 m / sec, it becomes easy to spheroidize.

<Capsule toner>
Next, the capsule toner of the present invention will be described in detail. The capsule toner of the present invention is a capsule toner comprising toner base particles and a coating layer formed on the surface of the toner base particles, and the capsule toner has a circularity of 0.96 or less. The surface arithmetic average height is 0.1 μm or more and 0.5 μm or less. If the circularity and the surface arithmetic average height of the capsule toner are within the above specified range, the spheroidization of the capsule toner is suppressed, and the cleaning property can be improved. Moreover, the capsule toner of the present invention can be produced by the above-described method for producing a capsule toner of the present invention, whereby the resin fine particles can be prevented from peeling off from the capsule toner.

  In the capsule toner of the present invention, the circularity of the capsule toner is 0.96 or less, preferably 0.94 or more and 0.96 or less. If the circularity of the capsule toner is 0.96 or less, it is possible to suppress the occurrence of poor cleaning. On the other hand, when the circularity of the capsule toner is less than 0.94, the charging stability may be lowered.

  In the capsule toner of the present invention, the arithmetic average height (Ra) of the toner (particle) surface is extracted from the roughness curve by a reference length of 1 μm in the direction of the average line, and measured from the average line of the extracted portion. The absolute values of the deviations up to are totaled and averaged. The more Ra is, the rougher the surface is, and the smaller Ra is, the smoother the state is. As the measuring device, for example, a shape measuring microscope VK9510 manufactured by Keyence Corporation can be used.

  In the capsule toner of the present invention, the toner base particles are as described in the above <Method for producing capsule toner>. In the capsule toner of the present invention, the coating layer is obtained by forming resin fine particles into a film. Here, the resin fine particles are as described in the above <Method for producing capsule toner>.

  The capsule toner of the present invention can be used as a developer in an image forming apparatus using an electrophotographic method, but toner base particles having a coating layer may be used as a one-component developer, or the toner base particles may be What added the additive externally may be used as a one-component developer. The mixture of the capsule toner and carrier of the present invention can also be used as a two-component developer.

  The external additive has a function of imparting fluidity to the toner and controlling the charge amount of the toner, and examples thereof include silica, titanium oxide, silicon carbide, aluminum oxide, barium titanate, and the like. Those that have been surface treated (hydrophobized) with a silane coupling agent or the like are preferred.

  When the capsule toner of the present invention is used as a two-component developer, the two-component developer can be prepared by mixing the capsule toner and a carrier. Here, as the mixing device, for example, a powder mixer such as a V-type mixer (trade name: V-5, manufactured by Tokuju Kogakusho Co., Ltd.) can be used. The mixing ratio of the capsule toner and the carrier is preferably, for example, a mass ratio of 10:90 to 5:95. In addition, it does not specifically limit as a carrier, The carrier normally used for a two-component developer can be used, For example, a ferrite carrier etc. are mentioned.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples. First, a method for measuring each physical property value will be described.

(Physical property measurement)
[Glass transition temperature of binder resin and toner base particles]
Using a differential scanning calorimeter (trade name: Diamond DSC, manufactured by Perkin Elmer), a DSC curve was measured by heating 1 g of a sample at a heating rate of 10 ° C. per minute according to Japanese Industrial Standard (JIS) K7121-1987. . In the obtained DSC curve, the slope is maximized with respect to the straight line obtained by extending the base line on the high temperature side to the low temperature side from the endothermic peak corresponding to the glass transition, and the curve from the rising part of the peak to the vertex. The temperature at the intersection with the drawn tangent was defined as the glass transition temperature (Tg).

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

[Melting point of release agent]
Using a differential scanning calorimeter (trade name: Diamond DSC, manufactured by Perkin Elmer), according to Japanese Industrial Standard (JIS) K7121-1987, 1 g of the sample was increased from 20 ° C. to 200 ° C. at a heating rate of 10 ° C./min. The operation of heating and then rapidly cooling from 200 ° C. to 20 ° C. was repeated twice, and the DSC curve was measured. The temperature at the top of the endothermic peak corresponding to the melting of the DSC curve measured in the second operation was determined 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 As One Co., Ltd.) for 3 minutes at an ultrasonic frequency of 20 kHz to prepare a measurement sample. This sample for measurement was measured using a particle size distribution measuring apparatus (trade name: Multisizer III, manufactured by Beckman Coulter, Inc.) under the conditions of aperture diameter: 100 μm, number of measured particles: 50000 count, and volume particle size distribution of sample particles. From this, the volume average particle size was determined.

[Volume average particle diameter of resin fine particles]
A dynamic light scattering particle size distribution measuring device (trade name: Nanotrack, manufactured by Nikkiso Co., Ltd.) was used for measuring the volume average particle size of the resin fine particles. In order to prevent agglomeration of the measurement sample (resin fine particles), a dispersion liquid in which the measurement sample is dispersed in an aqueous solution containing Family Fresh (manufactured by Kao Corporation) is added and stirred, and then injected into the above-mentioned apparatus and measured twice. The average value was calculated. As measurement conditions, the measurement time was 30 seconds, the sample particle refractive index was 1.49, the dispersion medium was water, and the dispersion medium refractive index was 1.33. The volume particle size distribution of the measurement sample was measured, and from the measurement results, the particle diameter at which the cumulative volume from the small particle diameter side in the cumulative volume distribution was 50% was calculated as the volume average particle diameter (μm) of the resin fine particles.

[Glass transition temperature of resin fine particles]
Using a differential scanning calorimeter (trade name: Diamond DSC, manufactured by Perkin Elmer), a DSC curve was measured by heating 1 g of a sample at a heating rate of 10 ° C. per minute according to Japanese Industrial Standard (JIS) K7121-1987. . In the obtained DSC curve, the slope is maximized with respect to the straight line obtained by extending the base line on the high temperature side to the low temperature side from the endothermic peak corresponding to the glass transition, and the curve from the rising part of the peak to the vertex. The temperature at the intersection with the drawn tangent was defined as the glass transition temperature (Tg).

[Softening temperature of resin fine particles]
Using a flow characteristic evaluation apparatus (trade name: Flow Tester CFT-500D, 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 used as the softening temperature (Tm).

Example 1
A capsule toner was manufactured according to the flowchart shown in FIG. In the film forming step S3, the powder processing apparatus shown in FIGS. 1 and 2 was used. This powder processing apparatus is a modified version of the hybridization system NHS-3 manufactured by Nara Machinery Co., Ltd., specifically, an injection nozzle as a heating means and an injection nozzle as a cooling means in a circulation pipe And the temperature control jacket structure that can act as a heating means and a cooling means on the entire outer periphery of the stirring portion. In addition, the stirring means was installed so that the space | interval with the inner wall of a stirring part might open 10 mm or more.
[Toner mother particle production step S1]
100 parts by weight of styrene-acrylic resin (manufactured by Mitsubishi Rayon Co., Ltd.) and 30 parts by weight of carbon black (manufactured by Evonik Degussa: Nippon 60) have a maximum temperature of 150 ° C. The mixture was melt-kneaded so as to be, and after cooling, coarsely pulverized to a chip of 1 mm with a cutting mill to obtain a master batch of carbon black.
75 parts by mass of a styrene-acrylic resin (manufactured by Mitsubishi Rayon Co., Ltd.), 25 parts by mass of a master batch of carbon black, and 4 parts by mass of polypropylene wax (manufactured by Sanyo Kasei Kogyo Co., Ltd .: 550P) Manufactured at a peripheral speed of 35 m / sec of the stirring blade for 10 minutes to obtain a material mixture. The obtained mixture was melt-kneaded so that the maximum temperature might be 175 degreeC with a biaxial kneader (Ikegai company make: PCM30 type | mold), and the melt-kneaded material was obtained by cooling with a drum flaker. This melt-kneaded product is coarsely pulverized with a cutting mill (Orient Co., Ltd .: VM-16), then finely pulverized with a jet mill (Hosokawa Micron Co., Ltd.), and further classified with an air classifier (Hosokawa Micron Co., Ltd.). As a result, toner mother particles having a volume average particle diameter of 6.5 μm and a glass transition temperature of 50 ° C. were produced. The circularity of the toner base particles was 0.945.

[Resin fine particle preparation step S2]
Styrene, acrylic acid, and butyl acrylate are polymerized to form styrene-acrylic acid-butyl acrylate copolymer resin fine particles having a solid content of 40% by mass and a volume average particle size of 0.10 μm (glass transition temperature of 64 ° C. , Softening temperature 120 ° C.) to obtain an emulsion.

[Film forming step S3]
・ Temperature adjustment step S3a
Heating component: The temperature of the heating component (air) to be brought into contact with the powder particles using the spray nozzle 203a was adjusted to 55 ° C.
Cooling component: The temperature of the cooling component (air) to be brought into contact with the powder particles is adjusted to 10 ° C. using the spray nozzle 203b, and the temperature adjusting jacket 203c of the powder processing apparatus 201 is used. The wall surface temperature of the powder flow part 209, the stirring part 208, and the stirring means 204 was adjusted to 10 ° C.
・ Composite powder particle forming step S3b
While rotating the stirring means 204 at a peripheral speed of 60 m / sec at the outermost periphery, the toner base particles and the resin fine particles are supplied from the powder input unit 206 to the powder flow path 202 and stirred and mixed for 5 minutes to obtain a composite powder. Particles were obtained. The mixing ratio of the resin fine particles to 100 parts by mass of the toner base particles was 7.0 parts by mass in terms of solid content. Further, during the stirring by the stirring means 204, the toner base particles, the resin fine particles, and the composite powder fine particles are flowing in the powder flow path 202 in a fluid state in which they are dispersed and suspended in the air, and the temperature of the air is 25. ° C.
・ Heating component process S3c
Thereafter, while rotating the stirring means 204 at a peripheral speed of 60 m / sec at the outermost periphery, the heating powder is applied to the composite powder fine particles flowing through the powder flow passage interior 250 by the injection nozzle 203a at 10 L / min. The resin fine particles on the surface of the toner base particles were melted to form a film by contacting for 5 minutes at a flow rate. In addition, 55 degreeC air was used as a heating component.
・ Cooling component process S3d
In parallel with the heating component step S3c, the cooling powder is brought into contact with the composite powder particles at a flow rate of 10 L / min for 5 minutes by the spray nozzle 203b located on the downstream side of the spray nozzle 203a. Aggregation of body particles was prevented. In addition, 10 degreeC air was used as a cooling component. Further, in the temperature adjusting jacket 203c, 10 ° C. cooling water was refluxed at a flow rate of 10 L / min and used as a cooling means.
・ Recovery process S3e
Thereafter, the injection nozzle 203a and the injection nozzle 203b were stopped, and the composite powder particles dispersed and suspended in the air were stirred for 5 minutes while maintaining the peripheral speed at the outermost periphery at 60 m / sec.

  The composite powder particles obtained by the collecting step S3e were used as the capsule toner of Example 1. The capsule toner of Example 1 had a circularity of 0.946 and a surface arithmetic average height of 0.5 μm.

(Example 2)
In the same manner as in Example 1, a capsule toner was manufactured according to the flowchart shown in FIG. In the film forming step S3, the same powder processing apparatus as in Example 1 was used.
[Toner mother particle production step S1]
In the same manner as in Example 1, toner mother particles were prepared. Since the toner base particles were subjected to spheronization using a mechanical pulverizer turbo mill (manufactured by Turbo Kogyo Co., Ltd.) before the circularity measurement, the circularity of the toner base particles was 0.953.
[Resin fine particle preparation step S2]
Similar to Example 1, styrene-acrylic acid-butyl acrylate copolymer resin fine particles (glass transition temperature 64 ° C., softening temperature 120 ° C.) emulsion having a solid content of 40% by mass and a volume average particle size of 0.10 μm Got.
[Film forming step S3]
The film forming step was performed in the same manner as in Example 1. The composite powder particles obtained by the recovery process were used as the capsule toner of Example 2. The capsule toner of Example 2 had a circularity of 0.954 and a surface arithmetic average height of 0.3 μm.

Example 3
In the same manner as in Example 1, a capsule toner was manufactured according to the flowchart shown in FIG. In the film forming step S3, the same powder processing apparatus as in Example 1 was used.
[Toner mother particle production step S1]
In the same manner as in Example 1, toner mother particles were prepared. Since the toner base particles were spheroidized using a mechanical pulverizer turbo mill (manufactured by Turbo Kogyo Co., Ltd.) before the circularity measurement, the circularity of the toner base particles was 0.960.
[Resin fine particle preparation step S2]
Similar to Example 1, styrene-acrylic acid-butyl acrylate copolymer resin fine particles (glass transition temperature 64 ° C., softening temperature 120 ° C.) emulsion having a solid content of 40% by mass and a volume average particle size of 0.10 μm Got.
[Film forming step S3]
The film forming step was performed in the same manner as in Example 1. The composite powder particles obtained by the recovery process were used as the capsule toner of Example 3. The capsule toner of Example 3 had a circularity of 0.960 and a surface arithmetic average height of 0.1 μm.

Example 4
In the same manner as in Example 1, a capsule toner was manufactured according to the flowchart shown in FIG. In the film forming step S3, the same powder processing apparatus as in Example 1 was used.
[Toner mother particle production step S1]
As in Example 1, toner base particles having a circularity of 0.945 were prepared.
[Resin fine particle preparation step S2]
Resin fine particles were prepared in the same manner as in Example 1, but the volume average particle size of the resin fine particles was adjusted to 0.50 μm by adjusting the dispersion conditions and polymerization time during polymerization.
[Film forming step S3]
The film forming step was performed in the same manner as in Example 1. The composite powder particles obtained by the recovery process were used as the capsule toner of Example 4. The capsule toner of Example 4 had a circularity of 0.945 and a surface arithmetic average height of 0.5 μm.

(Example 5)
In the same manner as in Example 1, a capsule toner was manufactured according to the flowchart shown in FIG. In the film forming step S3, the same powder processing apparatus as in Example 1 was used.
[Toner mother particle production step S1]
As in Example 3, toner base particles having a circularity of 0.960 were prepared.
[Resin fine particle preparation step S2]
Similar to Example 4, styrene-acrylic acid-butyl acrylate copolymer resin fine particles (glass transition temperature 64 ° C., softening temperature 120 ° C.) emulsion having a solid content of 40% by mass and a volume average particle size of 0.50 μm Got.
[Film forming step S3]
The film forming step was performed in the same manner as in Example 1. The composite powder particles obtained by the recovery process were used as the capsule toner of Example 5. The capsule toner of Example 5 had a circularity of 0.960 and a surface arithmetic average height of 0.5 μm.

(Example 6)
In the same manner as in Example 1, a capsule toner was manufactured according to the flowchart shown in FIG. In the film forming step S3, the same powder processing apparatus as in Example 1 was used.
[Toner mother particle production step S1]
As in Example 3, toner base particles having a circularity of 0.960 were prepared.
[Resin fine particle preparation step S2]
Similar to Example 1, styrene-acrylic acid-butyl acrylate copolymer resin fine particles (glass transition temperature 64 ° C., softening temperature 120 ° C.) emulsion having a solid content of 40% by mass and a volume average particle size of 0.10 μm Got.
[Film forming step S3]
The film forming step was performed in the same manner as in Example 1. However, in the heating component step S3c, the heating component was changed from 55 ° C. air to 30 ° C. air. In the cooling component step S3d, the temperature adjusting jacket 203c was not refluxed with 10 ° C. cooling water and was not used as a cooling means. The composite powder particles obtained by the recovery process were used as the capsule toner of Example 6. The capsule toner of Example 6 had a circularity of 0.960 and a surface arithmetic average height of 0.1 μm.

(Example 7)
In the same manner as in Example 1, a capsule toner was manufactured according to the flowchart shown in FIG. In the film forming step S3, the same powder processing apparatus as in Example 1 was used.
[Toner mother particle production step S1]
As in Example 3, toner base particles having a circularity of 0.960 were prepared.
[Resin fine particle preparation step S2]
Similar to Example 1, styrene-acrylic acid-butyl acrylate copolymer resin fine particles (glass transition temperature 64 ° C., softening temperature 120 ° C.) emulsion having a solid content of 40% by mass and a volume average particle size of 0.10 μm Got.
[Film forming step S3]
The film forming step was performed in the same manner as in Example 1. However, in the heating component step S3c, the heating component was changed from 55 ° C. air to 64 ° C. air. The composite powder particles obtained by the recovery process were used as the capsule toner of Example 7. The capsule toner of Example 7 had a circularity of 0.960 and a surface arithmetic average height of 0.1 μm.

(Example 8)
In the same manner as in Example 1, a capsule toner was manufactured according to the flowchart shown in FIG. In the film forming step S3, the same powder processing apparatus as in Example 1 was used.
[Toner mother particle production step S1]
As in Example 3, toner base particles having a circularity of 0.960 were prepared.
[Resin fine particle preparation step S2]
Similar to Example 1, styrene-acrylic acid-butyl acrylate copolymer resin fine particles (glass transition temperature 64 ° C., softening temperature 120 ° C.) emulsion having a solid content of 40% by mass and a volume average particle size of 0.10 μm Got.
[Film forming step S3]
The film forming step was performed in the same manner as in Example 1. However, in the cooling component step S3d, the temperature adjusting jacket 203c was not refluxed with 10 ° C. cooling water and was not used as a cooling means. The composite powder particles obtained by the recovery process were used as the capsule toner of Example 8. The capsule toner of Example 8 had a circularity of 0.960 and a surface arithmetic average height of 0.1 μm.

Example 9
In the same manner as in Example 1, a capsule toner was manufactured according to the flowchart shown in FIG. In the film forming step S3, the powder processing apparatus shown in FIG. 3 was used. This powder processing apparatus is a modified version of the hybridization system NHS-3 manufactured by Nara Machinery Co., Ltd., specifically, an injection nozzle as a heating means and an injection nozzle as a cooling means in a circulation pipe And a temperature adjusting jacket structure capable of acting as a heating means and a cooling means on the entire outer periphery of the stirring portion, and a cyclone was attached to the powder flow portion. In addition, the stirring means was installed so that the space | interval with the inner wall of a stirring part might open 10 mm or more.
[Toner mother particle production step S1]
As in Example 3, toner base particles having a circularity of 0.960 were prepared.
[Resin fine particle preparation step S2]
Similar to Example 1, styrene-acrylic acid-butyl acrylate copolymer resin fine particles (glass transition temperature 64 ° C., softening temperature 120 ° C.) emulsion having a solid content of 40% by mass and a volume average particle size of 0.10 μm Got.
[Film forming step S3]
The film forming step was performed in the same manner as in Example 1. However, in the cooling component step S3d, the temperature adjusting jacket 203c was not refluxed with 10 ° C. cooling water and was not used as a cooling means. The composite powder particles obtained by the recovery process were used as the capsule toner of Example 10. The capsule toner of Example 10 had a circularity of 0.960 and a surface arithmetic average height of 0.1 μm.

(Example 10)
In the same manner as in Example 1, a capsule toner was manufactured according to the flowchart shown in FIG. In the film forming step S3, the powder processing apparatus shown in FIGS. 4 and 5 was used. This powder processing apparatus is a modified Henshell mixer trade name: FM20C manufactured by Nippon Coke Industries, Ltd., specifically, a cylindrical stirring tank constituting the stirring unit, a spray nozzle as a heating means, An injection nozzle as a cooling means is attached, and the entire outer periphery of the agitating portion is made into a temperature adjusting jacket structure that can act as a heating means and a cooling means. Further, a cyclone and an exhaust port are attached above the openable upper lid constituting the agitating portion. . In addition, the stirring means was installed so that the space | interval with the inner wall of a stirring part might open 10 mm or more.
[Toner mother particle production step S1]
As in Example 3, toner base particles having a circularity of 0.960 were prepared.
[Resin fine particle preparation step S2]
Similar to Example 1, styrene-acrylic acid-butyl acrylate copolymer resin fine particles (glass transition temperature 64 ° C., softening temperature 120 ° C.) emulsion having a solid content of 40% by mass and a volume average particle size of 0.10 μm Got.
[Film forming step S3]
The film forming step was performed in the same manner as in Example 1. However, in the cooling component step S3d, the temperature adjusting jacket 203c was not refluxed with 10 ° C. cooling water and was not used as a cooling means. The composite powder particles obtained by the recovery process were used as the capsule toner of Example 11. The capsule toner of Example 11 had a circularity of 0.960 and a surface arithmetic average height of 0.1 μm.

(Example 11)
In the same manner as in Example 1, a capsule toner was manufactured according to the flowchart shown in FIG. In the film forming step S3, the powder processing apparatus shown in FIG. 6 was used. This powder processing apparatus is a modification of Henshell mixer trade name: FM20C manufactured by Nihon Coke Kogyo Co., Ltd. Specifically, an injection nozzle as a heating means is attached to a cylindrical stirring tank constituting the stirring section. In addition, a temperature adjusting jacket structure capable of acting as a heating means and a cooling means on the entire outer periphery of the agitation unit was provided, and a cyclone and an exhaust port were attached above the openable upper lid constituting the agitation unit. Moreover, as a cooling means, the cooling component introduction path was attached so that a cooling component could be introduce | transduced from the clearance gap between the through-hole in the bottom wall of a cylindrical stirring tank and a rotating shaft member. In addition, the stirring means was installed so that the space | interval with the inner wall of a stirring part might open 10 mm or more.
[Toner mother particle production step S1]
As in Example 3, toner base particles having a circularity of 0.960 were prepared.
[Resin fine particle preparation step S2]
Similar to Example 1, styrene-acrylic acid-butyl acrylate copolymer resin fine particles (glass transition temperature 64 ° C., softening temperature 120 ° C.) emulsion having a solid content of 40% by mass and a volume average particle size of 0.10 μm Got.
[Film forming step S3]
The film forming step was performed in the same manner as in Example 1. However, in the cooling component step S3d, the temperature adjusting jacket 203c was not refluxed with 10 ° C. cooling water and was not used as a cooling means. The composite powder particles obtained by the recovery process were used as the capsule toner of Example 11. The capsule toner of Example 11 had a circularity of 0.960 and a surface arithmetic average height of 0.1 μm.

(Example 12)
In the same manner as in Example 1, a capsule toner was manufactured according to the flowchart shown in FIG. In the film forming step S3, the same powder processing apparatus as in Example 1 was used.
[Toner mother particle production step S1]
As in Example 1, toner base particles having a circularity of 0.945 were prepared.
[Resin fine particle preparation step S2]
Similar to Example 4, styrene-acrylic acid-butyl acrylate copolymer resin fine particles (glass transition temperature 64 ° C., softening temperature 120 ° C.) emulsion having a solid content of 40% by mass and a volume average particle size of 0.50 μm Got.
[Film forming step S3]
The film forming step was performed in the same manner as in Example 1. However, in heating component process S3c, the heating component was changed from 55 degreeC air to 66 degreeC air. The composite powder particles obtained by the recovery process were used as the capsule toner of Example 12. The capsule toner of Example 12 had a circularity of 0.950 and a surface arithmetic average height of 0.3 μm. However, the presence of aggregates was confirmed in the capsule toner of Example 12.

(Reference Example 1)
In the same manner as in Example 1, a capsule toner was manufactured according to the flowchart shown in FIG. In the film forming step S3, the same powder processing apparatus as in Example 1 was used.
[Toner mother particle production step S1]
As in Example 1, toner base particles having a circularity of 0.945 were prepared.
[Resin fine particle preparation step S2]
Similar to Example 4, styrene-acrylic acid-butyl acrylate copolymer resin fine particles (glass transition temperature 64 ° C., softening temperature 120 ° C.) emulsion having a solid content of 40% by mass and a volume average particle size of 0.50 μm Got.
[Film forming step S3]
The film forming step was performed in the same manner as in Example 1. However, in the heating component step S3c, the heating component was changed from 55 ° C. air to 28 ° C. air. The composite powder particles obtained by the recovery process were used as the capsule toner of Reference Example 1. The capsule toner of Reference Example 1 had a circularity of 0.945 and a surface arithmetic average height of 0.6 μm. In the capsule toner of Reference Example 1, the presence of many resin fine particles separated from the toner base particles was confirmed.

(Reference Example 2)
In the same manner as in Example 1, a capsule toner was manufactured according to the flowchart shown in FIG. In the film forming step S3, the same powder processing apparatus as in Example 1 was used.
[Toner mother particle production step S1]
In the same manner as in Example 1, toner mother particles were prepared. Since the toner base particles were spheroidized using a mechanical pulverizer turbo mill (manufactured by Turbo Kogyo Co., Ltd.) before the circularity measurement, the circularity of the toner base particles was 0.970.
[Resin fine particle preparation step S2]
Similar to Example 1, styrene-acrylic acid-butyl acrylate copolymer resin fine particles (glass transition temperature 64 ° C., softening temperature 120 ° C.) emulsion having a solid content of 40% by mass and a volume average particle size of 0.10 μm Got.
[Film forming step S3]
The film forming step was performed in the same manner as in Example 1. The composite powder particles obtained by the recovery process were used as the capsule toner of Reference Example 2. The capsule toner of Reference Example 2 had a circularity of 0.970 and a surface arithmetic average height of 0.1 μm. In the capsule toner of Reference Example 2, the presence of many resin fine particles separated from the toner base particles was confirmed.

  In Example 11 of Table 1, the item “cooling component set temperature (injection nozzle)” indicates the set temperature of the cooling component introduced from the cooling component introduction path.

DESCRIPTION OF SYMBOLS 201 Powder processing apparatus 202 Powder flow path 203a Injection nozzle 203b Injection nozzle 203c Temperature adjustment jacket 204 Agitation means 206 Powder input part 207 Powder recovery part 208 Agitation part 208a, 208b, 208c Surface 209 Powder flow part 210 , 211 opening 212 supply pipe 213 solenoid valve 214 powder flow direction 215 collection tank 216 collection pipe 217 solenoid valve 218 rotating shaft member 219 rotating plate 220 stirring blade 221 through hole 250 inside powder passage

Claims (6)

  Powder flow path for flowing powder particles dispersed and suspended in gas, stirring means for stirring powder particles in a gas atmosphere, and heating to powder particles dispersed and suspended in gas A powder processing apparatus comprising heating means for contacting the components.   The powder processing apparatus according to claim 1, further comprising a cooling means for bringing a cooling component into contact with the powder particles dispersed and suspended in the gas. By stirring the toner base particles having a circularity of 0.96 or less and the resin fine particles having a volume average particle diameter of 0.1 μm or more and 0.5 μm or less in a gas atmosphere, the resin fine particles adhere to the surface of the toner base particles. A composite powder particle forming step for forming composite powder particles;
A heating component step in which a heating component is brought into contact with the composite powder particle to melt and form a resin fine particle on the surface of the toner base particle in a system in which the composite powder particle is dispersed and suspended in a gas. A method for producing a capsule toner.   The method for producing a capsule toner according to claim 3, further comprising a cooling component step in which a cooling component is brought into contact with the composite powder particles obtained by the heating component step.   5. The method for producing a capsule toner according to claim 3, wherein the heating component contains air or water vapor, and the temperature of the heating component is 30 ° C. or more and not more than the glass transition temperature of the resin fine particles.   A capsule toner comprising toner mother particles and a coating layer formed on the surface of the toner mother particles, wherein the capsule toner has a circularity of 0.96 or less, and the capsule toner has a surface arithmetic average height of 0. A capsule toner having a particle size of 1 μm or more and 0.5 μm or less.