JP4847286B2 - Toner particle manufacturing apparatus and manufacturing method - Google Patents

Description

  The present invention relates to an apparatus and a method for producing toner particles contained in toner for developing an electrostatic latent image in an image forming method such as an electrophotographic method, an electrostatic recording method, and a toner jet method.

  In the suspension polymerization method / dissolution suspension method, toner particles having a desired particle diameter are formed in a liquid dispersion medium to obtain a dispersion of toner particles. Thereafter, the toner particles are separated from the dispersion liquid of the toner particles by using a separation unit typified by a solid-liquid separation device such as a filtration device, and washed to remove impurities. The obtained wet toner particle cake is dried and classified as necessary, and then a predetermined additive is added to produce a toner (for example, see Patent Document 1).

  In the emulsion polymerization method, first, a monomer composition containing a polymerizable monomer, a polymerization initiator, a surfactant and, if necessary, a crosslinking agent, a chain transfer agent, and other additives in an aqueous medium. Dispersion using a stirrer and simultaneous polymerization reaction are performed to obtain emulsified resin particles having a desired particle size. On the other hand, a colorant is uniformly finely dispersed in an aqueous medium containing a surfactant and is associated (aggregated and fused) with the emulsified resin particles to obtain a dispersion of toner particles having a desired particle size. .

  Thereafter, the toner is manufactured through filtration, washing, drying, and classification in the same manner as in the suspension polymerization method and the dissolution suspension method (see, for example, Patent Document 2).

  Such wet-granulated toner particles are produced in a liquid dispersion medium, and therefore the surface thereof is easily affected by various components dispersed or dissolved in the liquid dispersion medium. For example, in the suspension polymerization method, an aqueous medium containing various dispersion stabilizers is generally used as the liquid dispersion medium, and the dispersion stabilizer adheres to the surface of the toner particles to be generated.

  In addition, in order to improve the chargeability, the toner produced by the suspension polymerization method is generally polymerized by including a positively or negatively chargeable charge control agent in the polymerizable monomer composition. . A part of the charge control agent having a high polarity dissolves in the aqueous dispersion medium and adheres to the surface of the toner particles to be generated. If the various components adhering to the surface of the toner particles are sufficiently and uniformly washed and not removed in the filtration / washing process after the polymerization, the toner charge amount distribution becomes broad, particularly under high temperature and high humidity conditions. The density is lowered and fog is likely to occur.

  Furthermore, when producing toner particles by the emulsion aggregation method, it is necessary to use a surfactant as an emulsifier. When a large amount of surfactant remains on the surface of the toner particles to be produced, there is a tendency that image density lowering and fogging occur more remarkably than suspension polymerization. For this reason, various methods for cleaning the generated toner particles have been proposed in a method for producing toner particles that are granulated in a wet manner.

  For example, a method of separating and cleaning toner particles from a dispersion of toner particles using a belt filter in which a filter cloth and a vacuum tray are in close contact with each other as a filter cleaning machine has been proposed (for example, see Patent Document 3). According to the method described in Patent Document 3, a toner having excellent image characteristics can be obtained by efficiently separating and washing toner particles from a dispersion of toner particles.

  This method is an excellent separation / washing method. However, in recent years, with the diversification of needs by users, high-definition images such as photographic image quality are required for electrophotographic images. In order to obtain a high-definition image in an electrophotographic image, one effective means is to reduce the toner particle size. If this particle size reduction is performed by a pulverization method, a great amount of pulverization energy is required, which is not preferable. On the other hand, in the wet granulation method, it is easy to reduce the toner particle size. However, when the particle size is reduced, when toner particles are separated from the dispersion of toner particles, water drainage is poor, and the moisture content of the obtained wet toner particle cake tends to increase. This is presumably because the surface area of the particles per unit volume of the cake formed with wet toner particles increases. This deterioration of water drainage leads to insufficient cleaning of various components adhering to the surface of the toner particles.

  As a method for avoiding this deterioration of water drainage, a filtration / washing method using a ditarancy effect has been proposed (for example, see Patent Document 4). It is described that in this method, a ditalancy effect is obtained by impact / vibration, and the moisture content is reduced by liquefaction of the cake. However, it is desired for this method to reduce the moisture content of the cake.

  Further, according to the solid-liquid separation device described in Patent Documents 5 and 6, it is described that after the solid-liquid separation, warm air can be sent to the toner cake and dried to a moisture content of 10% by mass or less. However, in this apparatus, it takes a very long time to achieve a water content of 10% by mass or less. Furthermore, it takes a long time for solid-liquid separation and toner cake discharge, and productivity is significantly reduced.

  In addition to improvements in cleanability and drainage, improvements in productivity are also required.

  Further, a filter cloth traveling type belt filter provided with a pressing roll has been proposed (see, for example, Patent Document 7). This device is a device for reducing the moisture content of the cake by allowing the cake to pass between two upper and lower pressing rolls to perform dehydration.

  When this apparatus is used as a means for separating and cleaning toner particles from a dispersion of toner particles, the water content cannot be sufficiently reduced.

Japanese Patent Laid-Open No. 51-14895 JP-A-5-265252 JP 2002-365839 A JP 2004-302099 A JP 2005-156937 A JP-A-2005-193123 Japanese Patent Laid-Open No. 10-309409

  An object of the present invention is to provide a toner particle manufacturing apparatus and a manufacturing method that solve the above-described problems. That is, the present invention relates to a method for producing toner particles that are granulated in a wet manner, in which toner particles that reduce the water content of a cake of wet toner particles obtained by efficiently separating and washing toner particles from a toner particle dispersion are provided. An object of the present invention is to provide a manufacturing apparatus and a manufacturing method.

  It is another object of the present invention to provide a toner particle manufacturing apparatus and method having excellent image characteristics by efficiently separating and washing toner particles from a toner particle dispersion.

  As a result of intensive studies, the inventors of the present invention have made it possible to ventilate a suitable compressed gas while maintaining good cake formation with respect to a cake made of toner particles formed on a belt filter. The present inventors have found that the moisture content of the cake is lowered and completed the present invention.

  Further, by reducing the moisture content of the wet toner particle cake, it becomes possible to uniformly wash various components adhering to the toner particle surface, and the obtained toner forms excellent image characteristics. Was completed.

That is, in the present invention, a vacuum tray connected to a vacuum pump is disposed below an annular filter cloth that is driven to travel, and the aqueous dispersion medium in which toner particles produced in the aqueous dispersion medium are dispersed is used. Production of toner particles including a filter cloth traveling belt filter that collects the aqueous dispersion medium on a vacuum tray by a vacuum pump by supplying the filter on the filter cloth, and filters the toner particles as a cake on the filter cloth. In the device
In the state which has a gas discharge part for discharging gas, and sealed gas leak by being pressed on the filter cloth or the cake, or both, from the gas discharge part, the filter cloth, the cake, or both The present invention provides an apparatus for producing toner particles, characterized by having an elastic and rotatable seal ventilation roll that discharges the gas to the pressing side to dehydrate and dehydrates the cake .
The present invention also provides a toner particle manufacturing method using the toner particle manufacturing apparatus.

  According to the present invention, there is provided a method for producing toner particles capable of efficiently separating and washing toner particles from a dispersion of toner particles and capable of reducing the moisture content of the obtained wet toner particle cake. be able to. Furthermore, it is possible to provide a toner particle manufacturing apparatus and a manufacturing method capable of uniformly cleaning various components adhering to the toner particle surface and having excellent image characteristics.

  A preferred embodiment of the toner particle production apparatus and production method of the present invention will be described below with reference to FIG.

  In the belt filter shown in FIG. 1, a filter cloth 2 is stretched between guide rolls 1 and is continuously or intermittently driven in the direction of arrow C by the rotation of the guide rolls 1. Below the filter cloth 2, a fixed vacuum tray 4 divided into one or a plurality of pieces is installed. The vacuum tray 4 has a structure in which a vacuum action can be obtained by a vacuum pump (not shown).

  Various dispersion stabilizers exist on the surface of the toner particles in the dispersion of toner particles obtained by the various wet granulation methods described above. In order to dissolve or remove the dispersion stabilizer, a pretreatment suitable for each wet granulation method is performed. After this pretreatment, the toner particle dispersion is supplied onto the filter cloth 2 via the liquid feed port 3, and is filtered and dehydrated in the cake forming step by the vacuum action.

  For example, in the case of a wet granulation method using a suspension polymerization method, an acid treatment is performed to dissolve a dispersant present on the surface of toner particles. This foaming phenomenon adversely affects the filtration / dehydration effect in the cake forming process, and may reduce the efficiency. Therefore, when acid treatment is performed, it is preferable to select an apparatus and a method that suppress foaming.

  The filtered filtrate is collected in a vacuum tray and sent to a vacuum tank (not shown) from a filtrate tube (not shown). At this time, in order to make the vacuum action work effectively, it is preferable to drive the filter cloth 2 intermittently. While the vacuum action is being obtained, the filter cloth 2 and the vacuum tray 4 are in close contact and do not rub. It is preferable. When continuously driven, the filter cloth 2 and the vacuum tray 4 are liable to have a problem in adhesion, and it is difficult to obtain a high degree of vacuum. If a high degree of vacuum cannot be obtained, the filtration and dehydration effects will be reduced, making it difficult to effectively separate the toner particles from the liquid dispersion medium.

  Next, the cake 5 and the filter cloth 2 that have been filtered and dehydrated are sent in the direction of the arrow C by the rotation of the guide roll 1, and sent to a washing step having one or more cake washing devices 7 on the top. From the cake washing | cleaning apparatus 7, 1 type or multiple types of washing | cleaning liquid is sprayed as needed, and the soluble or disperse | distributed substance in the cake 5 is wash | cleaned and removed. These substances are discharged together with the filtrate collected in the vacuum tray 4. At this time, in order to obtain a high degree of vacuum as described above, it is preferable that the filter cloth 2 and the vacuum tray 4 are in close contact with each other and do not rub.

  Next, the washed cake 5 and filter cloth 2 are sent in the direction of arrow C by the rotation of the guide roll 1 and sent to the dehydration step. As shown in FIG. 1, the dewatering process is preferably divided into a plurality of spans (in FIG. 1, the dewatering process is depicted as two spans). Preferably it is provided.

  The ventilating dewatering mechanism according to the present invention is a seal ventilating roll mechanism 8 shown in the drawing.

  An effect can be obtained if at least one of the seal ventilating roll mechanisms 8 is provided in the filter cloth traveling belt filter.

  When there are multiple seal ventilation roll mechanisms, the area of the wet toner particle cake that cannot be ventilated and dehydrated by the seal ventilation roll installed on the upstream side with respect to the direction of travel of the filter cloth matches. However, since the downstream ventilating roll mechanism can reliably cover the aeration dehydration process, the dehydration action works effectively.

  In addition, by using multiple seal venting roll mechanisms, sharing the dewatering area of the wet toner particle cake with each seal venting roll increases the degree of freedom in designing a one-span stroke of the filter intermittent movement, and also provides a seal. Since the diameter per ventilation roll can be kept low, there is an advantage that the height of the entire apparatus can be kept compact.

  It is preferable that the seal ventilation roll is provided with a plurality of seal ventilation roll recesses 9 as shown in FIG. The shape of the seal vent roll recess 9 is not limited to the shape shown in FIG. 2, but when at least a part of the seal vent roll is brought into contact with the filter cloth, the wet toner particle cake, or both of them. Furthermore, it is preferable that a space is created between at least a part of the sealing air-permeable roll and the filter cloth or the cake of wet toner particles or both.

  The seal ventilation roll is preferably provided with a seal portion as indicated by 10 in FIG. Although the shape of the seal portion of the seal vent roll is not limited to the shape shown in FIG. 2, it is ensured that the seal vent roll is brought into contact with the filter cloth and / or the wet toner particle cake. It is preferable to have a function of contacting at a desired contact pressure and preventing leakage of a gas for ventilation described later.

  In order to perform aeration and dehydration, the seal ventilation roll preferably has a gas discharge part for discharging a gas as indicated by 11 in FIG. The shape of the gas discharge portion is not limited to the shape as shown in FIG. 2, but it may be at least one gas supply nozzle.

  Further, as shown in 11 of FIG. 3, the gas discharge unit may use a member that can supply gas uniformly from a wide area using a perforated material.

  Further, as shown in FIG. 4, even if the gas discharge part is made of a perforated material for the entire roll and the seal venting roll has a shape without a recess, gas can be uniformly supplied from a wide area in the wet toner particle contact part. If present, a good dehydrating effect can be obtained.

  Without the function of the discharge part, even if the wet toner particles can be squeezed, a sufficient water removal effect cannot be obtained because aeration is not performed.

  Further, when the compressed gas outlet 11 is clogged due to the state of the cake 5, the clogging may be prevented by covering with a filter or a mesh.

  Even if the entire roll is made of perforated material and the seal vent roll has a shape without a recess, a good dewatering effect can be obtained if gas can be uniformly supplied from a large area at the wet toner particle contact portion.

  Moreover, it is preferable that the gas discharge part is divided | segmented like FIG.2, FIG.3, FIG.4. It is preferable that one seal air-permeable roll is provided for each of the surfaces in contact with the filter cloth, the wet toner particle cake, or both.

  In addition, the gas flow path is such that even after the gas has passed through the gas discharge portion, the seal ventilation roll is on each of the surfaces in contact with the filter cloth, the wet toner particle cake, or both. It is preferable that they are separated from each other.

  Furthermore, when the ventilation operation is performed with the seal vent roll, the surface of the portion where the seal vent roll is in contact with the filter cloth, the wet toner particle cake, or both of them is applicable. Preferably, only the gas discharge path of the system to be selected is selected, and only the corresponding system is ventilated.

  The selection of the gas discharge path may be performed by a known conventional control method such as opening / closing of a valve. When the ventilation operation is performed without selectively performing the gas discharge path, the seal ventilation roll is connected to the filter cloth, the wet toner particle cake, or both of systems other than the surface that contacts the filter cloth. Gas is ejected from the gas discharge path, which is not preferable because there is a demerit of dust flying and loss of compressed gas.

  The seal vent roll mechanism 8 preferably has a structure in which the contact portion of the elastic seal vent roll with the wet toner particle cake can come into contact with and separate from the cake 5 by the contact / separation mechanism 12 shown in FIG. .

  The contact / separation mechanism 12 works, and the contact portion of the seal air-permeable roll with the wet toner particle cake comes into contact with the cake 5 and is pressed. Under the present circumstances, compressed gas is ventilated from the compressed gas exit 11, the moisture contained in the cake 5 reduces, and a moisture content is reduced favorably. Further, various components adhering to the toner particle surface together with moisture are separated from the toner particles, and uniform cleaning can be performed.

  The contact / separation mechanism 12 is not particularly limited as long as the contact / separation movement with the cake 5 is possible, but is preferably a hydraulic mechanism. In the case of a hydraulic mechanism, the pressure when the seal portion 9 and the cake 5 are in contact with each other can be easily adjusted, and it is also effective in controlling the contact / separation motion.

  As described above, the filter cloth 2 is preferably driven intermittently.

During the intermittent movement of the filter cloth, during the aeration and dehydration, the pressure P1 at which the contact portion of the seal ventilation roll with the wet toner particle cake is in pressure contact with the wet toner particle cake is:
100 (kPa) ≦ P1 ≦ 900 (kPa)
It is preferable that This pressure P <b> 1 is defined as a force for pressing a unit area out of the area where the contact portion of the seal air-permeable roll with the wet toner particle cake contacts the cake 5. As will be described later, when compressed gas is passed through the cake 5, it acts as a sealing pressure for preventing the compressed gas from passing outside the cake. Therefore, when P1 <100 (kPa), when the compressed gas is vented from the compressed gas outlet 11, the sealing pressure becomes insufficient and a good cake state cannot be maintained. If a good cake cannot be maintained, the cake 5 scatters like a rupture or cracks, making it difficult to separate the various components attached to the surface of the toner particles from the toner particles. Further, it is not preferable that 1000 (kPa) <P1 because the toner particles in the cake 5 may be deformed by the pressure of P1 to have an adverse effect.

  The member used in the contact portion of the sealing air-permeable roll with the wet toner particle cake is not particularly limited as long as the above-described sealing is sufficiently possible, but when the tensile strength of the member is D. 3 (Mpa) ≦ D ≦ 30 (Mpa) is preferable. When 3 (Mpa)> D, the durability of the member is poor, and when 30 (Mpa) <D, a good seal cannot be obtained. Among them, a particularly preferable member is EPDM (ethylene propylene rubber).

  On the other hand, when the filter cloth 2 travels while the filter cloth 2 is moving intermittently, it is desirable to reduce the pressure at the contact portion between the cake 5 and the cake of the wet toner particles of the seal ventilation roll by interlocking the contact / separation mechanism.

Specifically, during the filter cloth traveling during the intermittent movement of the filter cloth, the pressure P2 at which the contact portion of the seal ventilation roll with the wet toner particle cake presses against the wet toner particle cake is: ,
0 (kPa) ≦ P2 ≦ 200 (kPa)
It is preferable that This pressure P2 is defined as the force pressing down per unit area in the area where the wet toner particle contact portion of the sealing vent roll contacts the cake 5 in the same manner as P1.

  When 200 (kPa) <P2, the frictional force between the filter cloth and the vacuum tray 4 increases during traveling of the filter cloth, the power required for driving during the traveling of the filter cloth increases, and the influence of the filter cloth damage due to friction. Is also not preferable.

The compressed gas is preferably compressed air from the viewpoint of cost, more preferably dehumidified dry air. The pressure P3 of the compressed gas is
10 (kPa) ≦ P3 ≦ 700 (kPa)
It is preferable that When 10 (kPa)> P3, there is little ventilation and it is difficult to obtain a desired water content reduction. Further, when 700 (kPa) <P3, not only the cost for producing compressed gas becomes high, but also the above-mentioned good cake state maintenance becomes difficult.

  The dehydrated cake 5 is peeled off from the filter cloth 3 by the curvature caused by the guide roll 1.

  The moisture content of the obtained wet toner particle cake is preferably 30% or less. If it exceeds 30%, the transportation to the subsequent drying step is hindered, and the efficiency of the drying step itself is lowered, which is not preferable. Further, the drying step is preferably airflow drying in which the wet toner particle cake is dispersed in a powder form in a hot airflow and dried while being sent in parallel with the hot airflow. The air flow drying can dry a large amount of wet toner particles at a low cost in a short time.

  The method for producing toner particles of the present invention can also be preferably used for a method for producing magnetic toner particles. For example, a magnetic material used for producing magnetic toner particles in the case of wet granulation by suspension polymerization will be described below.

  The surface of the magnetic material used in the magnetic toner is preferably hydrophobized. When hydrophobizing the magnetic material, it is very preferable to use a method in which the surface treatment is carried out while hydrolyzing the coupling agent while dispersing the magnetic material particles so as to have a primary particle size in an aqueous medium. In this hydrophobization method, the magnetic particles are less likely to coalesce than in the gas phase, and the magnetic repulsion action between the magnetic particles due to the hydrophobization treatment works, so the magnetic material is almost in the state of primary particles. Surface treatment with.

  The method of treating the surface of the magnetic material while hydrolyzing the coupling agent in an aqueous medium does not require the use of a coupling agent that generates gas, such as chlorosilanes and silazanes. In addition, since the magnetic particles can be easily united in the gas phase so far, it is possible to use a highly viscous coupling agent that has been difficult to perform well, so the effect of hydrophobization is tremendous. It is.

Examples of the coupling agent that can be used in the surface treatment of the magnetic material according to the present invention include a silane coupling agent and a titanium coupling agent. More preferably used is a silane coupling agent, which has the following general formula R _m SiY _n
[Wherein, R represents an alkoxy group, m represents an integer of 1 to 3, Y represents a hydrocarbon group such as an alkyl group, a vinyl group, a glycidoxy group, or a methacryl group, and n represents an integer of 1 to 3. Show]
It is shown by.

  For example, the following are mentioned. Vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyl Diethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxy Silane, diphenyldimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, diphenyldiethoxysilane, n-butyltrimethoxysilane, isobutyl Trimethoxysilane, trimethyl methoxysilane, hydroxypropyl trimethoxysilane, n- hexadecyl trimethoxysilane, n- octadecyl trimethoxysilane.

  Among these, in order to further improve the dispersibility of the magnetic substance, it is preferable to use a silane coupling agent having a double bond, such as phenyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyl. Trimethoxysilane is more preferred. This is thought to be due to the better compatibility between the magnetic substance and the polymerizable monomer, particularly when the suspension polymerization is performed with a coupling agent having a double bond. The dispersibility of the magnetic material is good.

However, it is difficult to make the magnetic material sufficiently hydrophobic by using only the coupling agent having these double bonds, and due to the influence of the exposure of the magnetic material having insufficient hydrophobicity on the toner surface, The particle size distribution is also wide. The reason for this is not clear, but it is thought to be due to the inferior hydrophobicity of the coupling agent itself, the reactivity with the active groups on the surface of the magnetic material, and the coverage on the surface of the magnetic material. For this reason, in order to obtain sufficient hydrophobicity, it is more preferable to use together an alkyltrialkoxysilane coupling agent represented by the following formula.
_{C p H 2p + 1 -Si- (} OC q H 2q + 1) 3
[Wherein p represents an integer of 2 to 20, and q represents an integer of 1 to 3]

  In the above formula, when p is smaller than 2, the hydrophobizing treatment is easy, but it is difficult to sufficiently impart hydrophobicity, and it becomes difficult to suppress the exposure of the magnetic particles from the toner particles. On the other hand, when p is larger than 20, the hydrophobicity is sufficient, but the coalescence between the magnetic particles increases, making it difficult to sufficiently disperse the magnetic particles, and the particle size distribution becomes broad. . On the other hand, when q is larger than 3, the reactivity of the silane coupling agent is lowered and the hydrophobicity is not sufficiently performed.

  More preferably, an alkyltrialkoxysilane coupling agent in which p is an integer of 3 to 15 and q is 1 or 2 in the above formula is used.

  The treatment amount is 0.05 to 20 parts by mass, preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the magnetic material. It is preferable to adjust the amount of the treatment agent according to the surface area of the magnetic material and the reactivity of the coupling agent.

  Moreover, the aqueous medium used at the time of the hydrophobic treatment is a medium containing water as a main component. Specific examples of the aqueous medium include water itself, water added with a small amount of a surfactant, water added with a pH adjusting agent, and water added with an organic solvent. As the surfactant, a nonionic surfactant such as polyvinyl alcohol is preferable. The surfactant is preferably added in an amount of 0.1 to 5% by mass with respect to water. Examples of the pH adjuster include inorganic acids such as hydrochloric acid, and examples of the organic solvent include alcohols.

  In the case where a plurality of types of silane coupling agents are used, a plurality of types of coupling agents are added simultaneously or with a time difference, and the magnetic material is processed.

  In the magnetic material thus obtained, no particle aggregation is observed, and the surface of each particle is uniformly hydrophobized, so that the dispersibility of the magnetic material in the polymerizable monomer is good.

The magnetic material used in the toner of the present invention may contain elements such as phosphorus, cobalt, nickel, copper, magnesium, manganese, aluminum, and silicon. In addition, the magnetic substance is composed mainly of iron oxide such as triiron tetroxide and γ-iron oxide. These may be used alone or in combination of two or more. These magnetic materials preferably have a BET specific surface area by a nitrogen adsorption method of ² to 30 m ² / g, more preferably 3 to 28 m ² / g, and a Mohs hardness of 5 to 7.

  For example, in the case of a wet granulation method using a suspension polymerization method, the magnetic material used for the toner is preferably used in an amount of 10 to 200 parts by mass with respect to 100 parts by mass of the polymerizable monomer or binder resin. More preferably, 20 to 180 parts by mass are used. If it is less than 10 parts by mass, the coloring power of the toner is poor, and it is difficult to suppress fogging. On the other hand, when the amount exceeds 200 parts by mass, not only the retention force of the obtained toner due to the magnetic force on the toner carrier increases, but the developability decreases, and it is difficult not only to uniformly disperse the magnetic material to individual toner particles. , The fixing property is lowered.

  The content of the magnetic substance in the toner is measured with a thermal analyzer, TGA7, manufactured by PerkinElmer. In the measurement method, the toner is heated from normal temperature to 900 ° C. at a temperature increase rate of 25 ° C./min in a nitrogen atmosphere, and the weight loss from 100 ° C. to 750 ° C. is defined as the binder resin amount, and the residual mass is approximately calculated. The amount of magnetic material.

  For example, in the case of magnetite, the magnetic material used in the magnetic toner according to the present invention is manufactured by the following method. An aqueous solution containing ferrous hydroxide is prepared by adding an alkali such as sodium hydroxide in an amount equivalent to or higher than the iron component to the ferrous salt aqueous solution. While maintaining the pH of the prepared aqueous solution at 7 or higher (preferably pH 8 to 14), air is blown, and the aqueous iron oxide is heated to 70 ° C. or higher to oxidize ferrous hydroxide, and the core of the magnetic iron oxide particles First, a seed crystal is formed.

  Next, an aqueous solution containing about 1 equivalent of ferrous sulfate is added to the slurry-like liquid containing seed crystals based on the amount of alkali added previously. While maintaining the pH of the solution at 6 to 14, the reaction of ferrous hydroxide proceeds while blowing air to grow magnetic iron oxide particles with the seed crystal as the core. As the oxidation reaction proceeds, the pH of the liquid shifts to the acidic side, but the pH of the liquid is preferably not less than 6. Adjust the pH of the solution at the end of the oxidation reaction, stir well so that the magnetic iron oxide becomes primary particles, add the coupling agent, stir well, stir, filter, dry, and lightly crush after stirring By doing so, hydrophobic treated magnetic iron oxide particles can be obtained. Alternatively, after the oxidation reaction is completed, the iron oxide particles obtained by washing and filtering are redispersed in another aqueous medium without drying, and then the pH of the redispersion is adjusted and the silane is stirred well. A coupling agent may be added to perform the coupling treatment. In any case, it is important to perform the surface treatment after the oxidation reaction without passing through the drying step, which is one of the important points in the present invention.

  As the ferrous salt, iron sulfate generally produced as a by-product in the production of sulfuric acid titanium, iron sulfate produced as a by-product with the surface cleaning of the steel sheet can be used, and iron chloride or the like can be used.

  In the production method of magnetic iron oxide by the aqueous solution method, when iron sulfate is used, generally an aqueous solution having an iron concentration of 0.5 to 2 mol / l is used from the viewpoint of preventing the viscosity from increasing during the reaction and the solubility of iron sulfate. It is done. Generally, the lower the iron sulfate concentration, the finer the particle size of the product. Further, in the reaction, the more the amount of air is and the lower the reaction temperature is, the easier it is to atomize.

  By using the magnetic toner made of the hydrophobic magnetic particles produced as described above, stable toner charging property can be obtained, transfer efficiency is high, and high image quality and high stability are possible.

  The magnetic material obtained as described above can be suitably used as a colorant contained in the toner particles. Examples of the colorant other than the magnetic material that can be suitably used in the toner produced in the present invention include carbon black and the following yellow / magenta / cyan colorants.

  As a colorant suitable for the yellow color, a pigment or a dye can be used. Specifically, the following are mentioned as a pigment. C. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 17, 23, 62, 65, 73, 74, 81, 83, 93, 94, 95, 97, 98, 109, 110, 111, 117, 120, 127, 128, 129, 137, 138, 139, 147, 151, 154, 155, 167, 168, 173, 174, 176, 180, 181, 183, 191 and C.I. I. Bat yellow 1, 3, 20 Examples of the dye include C.I. I. Solvent yellow 19, 44, 77, 79, 81, 82, 93, 98, 103, 104, 112, 162 may be mentioned. These may be used alone or in combination of two or more.

  As a colorant suitable for magenta, a pigment or a dye can be used. Specifically, examples of the magenta pigment include the following. C. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48, 48; 2, 48; 3, 48; 4, 49, 50, 51, 52, 53, 54, 55, 57, 57; 1, 58, 60, 63, 64, 68, 81, 81; 1, 83, 87, 88, 89, 90, 112, 114, 122, 123, 144, 146, 150, 163, 166, 169, 177, 184, 185, 202, 206, 207, 209, 220, 221, 238, 254; I. Pigment violet 19; C.I. I. Vat Red 1, 2, 10, 13, 15, 23, 29, 35. Examples of the magenta dye include the following. C. I. Solvent Red 1, 3, 8, 23, 24, 25, 27, 30, 49, 52, 58, 63, 81, 82, 83, 84, 100, 109, 111, 121, 122; I. Disper thread 9, C.I. I. Solvent Violet 8, 13, 14, 21, 27; C.I. I. Oil-soluble dyes such as Disperse Violet 1; I. B. Basic Red 1, 2, 9, 12, 13, 14, 15, 17, 18, 22, 23, 24, 27, 29, 32, 34, 35, 36, 37, 38, 39, 40; I. Basic dyes such as basic violet 1,3,7,10,14,15,21,25,26,27,28, and these may be used alone or in combination of two or more.

  As a colorant suitable for cyan, a pigment or a dye can be used. Specifically, the following are mentioned as a cyan pigment. C. I. Pigment Blue 1, 7, 15, 15: 1, 15: 2, 15: 3, 15: 4, 16, 17, 60, 62, 66; I. Bat Blue 6, C.I. I. Acid Blue 45 and the dye include C.I. I. Solvent Blue 25, 36, 60, 70, 93, 95 can be mentioned. These may be used alone or in combination of two or more.

  These colorants can be used singly or in combination of two or more, or can be used in the form of a solid solution. The colorant is selected from the viewpoint of hue angle, saturation, brightness, weather resistance, OHP transparency, and dispersibility in the toner. For example, in the case of the wet granulation method by the suspension polymerization method, the coloring agent is added in an amount of 1 to 20 parts by mass with respect to 100 parts by mass of the polymerizable monomer or binder resin.

  The toner particles produced in the present invention may contain a release agent. Examples of the release agent that can be used for the toner particles in the present invention include the following. Petroleum wax such as paraffin wax, microcrystalline wax, petrolatum and derivatives thereof; montan wax and derivatives thereof; hydrocarbon wax and derivatives thereof according to the Fischer-Tropsch method; polyolefin wax and derivatives thereof such as polyethylene wax and polypropylene wax; carnauba wax; Natural waxes such as candelilla wax and derivatives thereof. Derivatives include oxides, block copolymers with vinyl monomers, and graft modified products. Furthermore, the following are mentioned. Fatty acids such as higher fatty alcohols, stearic acid and palmitic acid, or compounds thereof, acid amide waxes, ester waxes, ketones, hydrogenated castor oil and derivatives thereof, plant waxes, animal waxes.

  Specific examples of the wax include the following. Biscol (registered trademark) 330-P, 550-P, 660-P, TS-200 (Sanyo Chemical Industries); High wax 400P, 200P, 100P, 410P, 420P, 320P, 220P, 210P, 110P (Mitsui Chemicals) ); Sazol H1, H2, C80, C105, C77 (Schumann Sazol); HNP-1, HNP-3, HNP-9, HNP-10, HNP-11, HNP-12 (Nippon Seiki Co., Ltd.); Unilin (registered trademark) 350, 425, 550, 700, Unicid (registered trademark), Unicid (registered trademark) 350, 425, 550, 700 (Toyo Petrolite); wood wax, beeswax, rice wax, candelilla wax Carnauba wax (available from Celerica NODA).

  A charge control agent may be blended in the toner particles. A well-known thing can be utilized as a charge control agent. Further, for example, in the case of a wet granulation method using a suspension polymerization method, when producing toner particles, a charge control agent having a low polymerization inhibitory property and substantially free from a solubilized product in an aqueous dispersion medium is particularly preferable. Examples of the negative charge control agent include the following. Metallic compounds of aromatic carboxylic acids such as salicylic acid, alkylsalicylic acid, dialkylsalicylic acid, naphthoic acid, dicarboxylic acid; metal salts or metal complexes of azo dyes or azo pigments; polymer type having sulfonic acid or carboxylic acid group in the side chain Compound: Boron compound, urea compound, silicon compound, calixarene. Examples of the positive charge control agent include the following. A quaternary ammonium salt, a polymer compound having the quaternary ammonium salt in the side chain, a guanidine compound, a nigrosine compound, and an imidazole compound.

  As a method of adding a charge control agent to the toner, there are a method of adding it inside the toner particles and a method of adding it externally to the toner particles. The amount of these charge control agents used is determined primarily by the type of polymerizable monomer or binder resin, the presence or absence of other additives, and the toner production method including the dispersion method, and is uniquely limited. It is not something. When added internally, it is preferably used in the range of 0.1 to 10 parts by mass, more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the polymerizable monomer or binder resin. When added externally, the amount is preferably 0.005 to 1.0 part by mass, more preferably 0.01 to 0.3 part by mass with respect to 100 parts by mass of the toner particles.

  In the present invention, for example, in the case of a wet granulation method using an emulsion polymerization method or a suspension polymerization method, examples of the polymerizable monomer used for the production of toner particles include the following.

Styrene monomers such as styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-ethylstyrene; methyl acrylate, ethyl acrylate, n-butyl acrylate, acrylic acid Acrylic esters such as isobutyl, n-propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate;
Methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, methacrylic acid Methacrylate esters such as dimethylaminoethyl, diethylaminoethyl methacrylate;
Acrylonitrile, methacrylonitrile, acrylamide.

  In the toner production method of the present invention, for example, in the case of wet granulation by suspension polymerization, resin may be added to the polymerizable monomer for polymerization. Hydrophilic functional groups such as amino groups, carboxylic acid groups, hydroxyl groups, sulfonic acid groups, glycidyl groups, and nitrile groups that cannot be used because polymerizable monomers dissolve in water and cause emulsion polymerization due to water solubility. When it is desired to introduce the polymerizable monomer unit having the above into the toner particles, it is preferably introduced in the following copolymer or polymer state. Random copolymers, block copolymers, or copolymers such as graft copolymers of these with vinyl compounds such as styrene or ethylene, or polycondensates such as polyester and polyamide, polyethers and polyimines. Polyaddition polymer.

  In the present invention, an alcohol component and an acid component constituting the polyester resin used by adding to the polymerizable monomer are exemplified below. The following are mentioned as an alcohol component. Ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol 2-ethyl-1,3-hexanediol, cyclohexanedimethanol, butenediol, octenediol, cyclohexenedimethanol, hydrogenated bisphenol A, a bisphenol derivative represented by the formula (I) or the formula (I) Hydrogenated compounds;

［式中、Ｒはエチレン基またはプロピレン基を示し、ｘ及びｙはそれぞれ１以上の整数であり、かつｘ＋ｙの平均値は２〜１０である。］
または、下記式（ＩＩ）で表されるジオール又は該式（ＩＩ）で表される化合物の水添物。

[Wherein, R represents an ethylene group or a propylene group, x and y are each an integer of 1 or more, and the average value of x + y is 2 to 10. ]
Alternatively, a diol represented by the following formula (II) or a hydrogenated product of the compound represented by the formula (II).

  Examples of the divalent carboxylic acid include the following. Benzene dicarboxylic acid or its anhydride such as phthalic acid, terephthalic acid, isophthalic acid, phthalic anhydride; alkyl dicarboxylic acid or its anhydride such as succinic acid, adipic acid, sebacic acid, azelaic acid, or further 6-18 carbon atoms A succinic acid substituted with an alkyl or alkenyl group or an anhydride thereof; an unsaturated dicarboxylic acid such as fumaric acid, maleic acid, citraconic acid, itaconic acid, or an anhydride thereof.

  Furthermore, the following are mentioned as an alcohol component. Polyhydric alcohols such as oxyalkylene ethers of glycerin, pentaerythritol, sorbit, sorbitan, and novolac phenolic resins. Examples of the acid component include the following. Multivalent carboxylic acids such as trimellitic acid, pyromellitic acid, 1,2,3,4-butanetetracarboxylic acid, benzophenonetetracarboxylic acid and its anhydride.

  It is preferable that 45-55 mol% of the said polyester resin is an alcohol component, and 55-45 mol% is an acid component in all the components. In the present invention, two or more kinds of polyester resins may be used in combination as long as the physical properties of the obtained toner particles are not adversely affected, or modified with, for example, silicone or a fluoroalkyl group-containing compound to adjust the physical properties. Is also preferably performed. Moreover, when using the high molecular polymer containing such a polar functional group, the weight average molecular weight is preferably 5,000 or more.

  Moreover, you may add resin other than the above in a polymerizable monomer composition. The following are mentioned as resin used. Polystyrene; homopolymer of styrene-substituted product such as polyvinyltoluene; styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-acrylic acid Ethyl copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-dimethylaminoethyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate Copolymer, styrene-butyl methacrylate copolymer, styrene-dimethylaminoethyl methacrylate copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer Coalescence, styrene-butadi Copolymer, styrene-isoprene copolymer, styrene-maleic acid copolymer, styrene copolymer such as styrene-maleic acid ester copolymer; polymethyl methacrylate, polybutyl methacrylate, polyvinyl acetate, polyethylene, Polypropylene, polyvinyl butyral, silicone resin, polyester resin, polyamide resin, epoxy resin, polyacrylic acid resin, rosin, modified rosin, terpene resin, phenol resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin. These can be used alone or in combination.

  As addition amount of these resin, 1-20 mass parts is preferable with respect to 100 mass parts of polymerizable monomers. If the amount is less than 1 part by mass, the effect of addition is small, while if it exceeds 20 parts by mass, it becomes difficult to design various properties of the polymerized toner.

  Further, a polymer having a molecular weight different from the molecular weight range of the toner obtained by polymerizing the monomer may be dissolved in the monomer for polymerization.

In the toner production method of the present invention, a polymerization initiator is used to initiate the polymerization reaction of the polymerizable monomer. When the polymerization reaction is carried out at an addition amount of 0.5 to 20 parts by mass with respect to 100 parts by mass of the polymerizable monomer, the half-life of 0.5 to 30 hours at the time of the polymerization reaction, the molecular weight is 10,000 to 100,000. A polymer having a maximum in between can be obtained, and the toner can be provided with desirable strength and suitable melting characteristics. Examples of the polymerization initiator include the following. 2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1′-azobis (cyclohexane-1-carbonitrile), 2,2′-azobis Azo or diazo polymerization initiators such as -4-methoxy-2,4-dimethylvaleronitrile, azobisisobutyronitrile;
Benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide, t-butylperoxy 2-ethylhexanoate, t-butylperoxypivalate Peroxide-based polymerization initiators such as

  When the toner of the present invention is produced, a crosslinking agent may be added, and a preferable addition amount is 0.001 to 15 parts by mass with respect to 100 parts by mass of the polymerizable monomer.

  Here, as the cross-linking agent, a compound having two or more polymerizable double bonds is mainly used. For example, the following are mentioned. Aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene; carboxylic acid esters having two double bonds such as ethylene glycol diacrylate, ethylene glycol dimethacrylate and 1,3-butanediol dimethacrylate; divinylaniline and divinyl ether Divinyl compounds such as divinyl sulfide and divinyl sulfone; compounds having three or more vinyl groups. These are used alone or as a mixture of two or more.

  In the present invention, for example, a specific toner production method when a wet granulation method by a suspension polymerization method is selected will be described.

  First, components necessary for the toner such as pigments, mold release agents, charge control agents, and crosslinking agents and other additives are added to the polymerizable monomer as appropriate, and uniformly dissolved or dispersed to obtain a colorant-containing polymerizability. A monomer composition is obtained. At this time, you may perform temperature control operation as needed. This colorant-containing polymerizable monomer composition is suspended and granulated in an aqueous medium containing a dispersion stabilizer.

  At this time, the colorant-containing polymerizable monomer composition is granulated at the same time or after granulation, and then the polymerization composition is polymerized by adding a polymerization initiator (polymerization step). The specific timing of addition of the polymerization initiator may be added simultaneously with the addition of other additives in the polymerizable monomer, or may be mixed immediately before being suspended in the aqueous medium. Moreover, a polymerization initiator dissolved in an additional polymerizable monomer or solvent during the polymerization reaction can be added immediately after granulation and before starting the polymerization reaction.

  After granulation, stirring may be performed to such an extent that the particle state is maintained and particle floating and sedimentation are prevented by using a normal stirrer while adjusting the temperature.

  When producing toner particles, known surfactants and organic / inorganic dispersants can be used as dispersion stabilizers. Among these, inorganic dispersants are preferred because they are less likely to produce harmful ultrafine powders, and because dispersion stability is obtained due to their steric hindrance, stability is not easily lost even when the reaction temperature is changed. The following are mentioned as an inorganic dispersing agent. Polyvalent metal phosphates such as calcium phosphate, magnesium phosphate, aluminum phosphate and zinc phosphate; carbonates such as calcium carbonate and magnesium carbonate; inorganic salts such as calcium metasuccinate, calcium sulfate and barium sulfate; calcium hydroxide and hydroxide Inorganic hydroxides such as magnesium and aluminum hydroxide; inorganic oxides such as silica, bentonite and alumina.

  These inorganic dispersants are preferably used alone in an amount of 0.2 to 20 parts by mass with respect to 100 parts by mass of the polymerizable monomer. You may use 0.001-0.1 mass part surfactant together.

  Examples of the surfactant include the following. Sodium dodecylbenzene sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, sodium stearate, potassium stearate.

  When these inorganic dispersants are used, they may be used as they are, but in order to obtain finer particles, the inorganic dispersant particles can be generated and used in an aqueous medium. For example, in the case of calcium phosphate, a sodium phosphate aqueous solution and a calcium chloride aqueous solution can be mixed with high-speed stirring to produce water-insoluble calcium phosphate, which enables more uniform and fine dispersion. At the same time, a water-soluble sodium chloride salt is produced as a by-product. However, if a water-soluble salt is present in the aqueous medium, dissolution of the polymerizable monomer in water is suppressed, and an ultrafine toner based on emulsion polymerization is produced. It is more convenient because it is less likely to occur. The inorganic dispersant can be dissolved with an acid or an alkali after the completion of the polymerization and removed almost completely by the next step such as filtration and washing.

  In the polymerization step, the polymerization is performed at a polymerization temperature of 40 ° C. or higher, generally 50 to 90 ° C. When the polymerization is carried out in this temperature range, the release agent or wax to be sealed inside is precipitated by phase separation, and the encapsulation becomes more complete. Further, in order to consume the remaining polymerizable monomer, the reaction temperature can be raised to 90 to 150 ° C. at the end of the polymerization reaction. After the completion of the polymerization reaction, the obtained toner particle dispersion is filtered and washed by the belt filter equipped with a pressure aeration mechanism according to the present invention as described above, and then preferably dried by an air flow drying device.

  In general, toner particles obtained by removing coarse powder and fine powder out of a desired particle size range in the classification process are obtained. The classification step can be carried out by a known method used in conventional toner production, and is not particularly limited. A toner can be obtained by mixing an external additive such as an inorganic fine powder with the toner particles obtained through the classification step and adhering them to the surface of the toner particles. In the present invention, it is one of desirable modes to directly obtain the toner by omitting the classification process from the manufacturing process or to cut coarse powder and fine powder with high precision by performing a more accurate classification process.

  In the present invention, it is also preferable that inorganic fine particles having a number average primary particle size of 4 to 80 nm are added to the toner as a fluidizing agent among the external additives.

Examples of the inorganic fine particles used in the present invention include silica, alumina, and titanium oxide. For example, as the silicic acid fine powder, both a so-called dry method produced by vapor phase oxidation of silicon halide or dry silica called fumed silica, and so-called wet silica produced from water glass or the like can be used. is there. Dry silica is preferred because it has less silanol groups on the surface and in the silica fine powder, and less production residue of Na ₂ O and SO ³⁻ . For dry silica, composite fine powders of silica and other metal oxides produced by using other metal halogen compounds such as aluminum chloride and titanium chloride together with silicon halogen compounds in the production process can also be used.

  The amount of inorganic fine particles having an average primary particle size of 4 to 80 nm is preferably 0.1 to 3.0% by mass with respect to the toner base particles. If the addition amount is less than 0.1% by mass, the effect is not sufficient, and if it exceeds 3.0% by mass, the fixability may be deteriorated. In addition, content of inorganic fine powder can be quantified using the analytical curve created from the standard sample using the fluorescent X ray analysis.

  The inorganic fine particles are preferably hydrophobized in view of characteristics in a high temperature and high humidity environment. Examples of the treatment agent for the hydrophobic treatment include the following. Silicone varnish, various modified silicone varnishes, silicone oil, various modified silicone oils, silane compounds, silane coupling agents, other organic silicon compounds, organic titanium compounds. These treatment agents may be used alone or in combination.

  As a method for treating the inorganic fine particles, for example, a method of forming a hydrophobic thin film on the surface with silicone oil as a second-stage reaction after performing a silylation reaction as a first-stage reaction to eliminate silanol groups by chemical bonding. Can be mentioned.

The silicone oil may have a viscosity at 25 ° C. is 10~200,000mm ² / s, more preferably from 3,000~80,000mm ² / s. If it is less than 10 mm ² / s, the inorganic fine particles are not stable, and the image quality tends to deteriorate due to heat and mechanical stress. If it exceeds 200,000 mm ² / s, uniform processing tends to be difficult.

  Examples of the silicone oil include the following. Dimethyl silicone oil, methylphenyl silicone oil, α-methylstyrene modified silicone oil, chlorophenyl silicone oil, fluorine modified silicone oil.

  As a method for treating silicone oil, for example, inorganic fine particles treated with a silane compound and silicone oil may be directly mixed using a mixer such as a Henschel mixer, or a method of spraying silicone oil onto inorganic fine particles. It may be used. Alternatively, after dissolving or dispersing silicone oil in a suitable solvent, inorganic fine particles may be added and mixed to remove the solvent. A method using a sprayer is more preferable in that the formation of inorganic fine particle aggregates is relatively small.

  The treatment amount of the silicone oil is 1 to 40 parts by mass, preferably 3 to 35 parts by mass with respect to 100 parts by mass of the inorganic fine particles.

Silica used in the present invention, in order to impart good fluidity to the toner, the specific surface area measured by the BET method by nitrogen adsorption of preferably within the scope of 20~350m ² / g, 25~300m ² / g is more preferable.

  In accordance with the BET method, the specific surface area is obtained by adsorbing nitrogen gas to the sample surface using a specific surface area measuring device Autosorb 1 (manufactured by Yuasa Ionics) and calculating the specific surface area using the BET multipoint method.

In addition, the toner of the present invention is a toner having, as an external additive, inorganic or organic spherical fine particles having a primary particle size of more than 30 nm, more preferably 50 nm or more, for the purpose of improving cleaning properties. It is one of the preferable forms to be added to the particles. As the inorganic or organic fine particles, those having a specific surface area of less than 50 m ² / g (more preferably a specific surface area of less than 30 m ² / g) can be preferably used. As such fine particles, for example, spherical silica particles, spherical polymethylsilsesquioxane particles, and spherical resin particles are preferably used.

  Other external additives can be externally added to the toner particles as long as they do not have a substantial adverse effect. Examples of other external additives include the following. Lubricant powders such as polyfluorinated ethylene powder, zinc stearate powder and polyvinylidene fluoride powder; abrasives such as cerium oxide powder, silicon carbide powder and strontium titanate powder; fluidity imparting agents such as titanium oxide powder and aluminum oxide powder; Anti-caking agent. In addition, a small amount of organic fine particles or inorganic fine particles having a reverse polarity can be used as a developability improver. These external additives can also be used after the surface is hydrophobized.

  The toner produced according to the present invention can be used as a one-component developer. For example, as a one-component developer, in the case of a polymerized toner containing a magnetic material in the toner, there is a method of conveying and charging the polymerized toner using a magnet built in the developing sleeve. However, the developer is not necessarily limited to the one-component developer as described above, and may be used as a two-component developer.

  When used as a two-component developer, a magnetic carrier is used together with the toner. As the magnetic carrier, an element selected from iron, copper, zinc, nickel, cobalt, manganese and chromium is used alone or in a composite ferrite state. The magnetic carrier has a spherical shape, a flat shape, or an indeterminate shape. Furthermore, it is preferable to control the fine structure (for example, surface unevenness) of the surface state of the magnetic carrier particles. Generally, after the inorganic oxide is fired and granulated to previously generate magnetic carrier core particles, a method of coating the carrier core particles with a resin is used. For the purpose of reducing the load of the magnetic carrier on the toner, a method of obtaining a low density dispersion carrier by kneading and classifying an inorganic oxide and a resin, or a kneaded product of an inorganic oxide and a monomer directly in an aqueous medium It is also possible to use a method in which suspension polymerization is performed to obtain a true spherical magnetic carrier.

  Among these, a coated carrier obtained by coating the surface of the carrier core particle with a resin is particularly preferable. As a method of coating the surface of the carrier core particles with the resin, the resin is dissolved or suspended in a solvent and applied to the carrier core by coating, or the resin powder and the carrier core particles are mixed and attached. Can be applied.

  Examples of substances adhering to the surface of the carrier particles vary depending on the toner material, but include the following. Polytetrafluoroethylene, monochlorotrifluoroethylene polymer, polyvinylidene fluoride, silicone resin, polyester resin, styrene resin, acrylic resin, polyamide, polyvinyl butyral, aminoacrylate resin. These may be used alone or in plural.

The magnetic properties of the carrier are as follows. The magnetization intensity (σ ₁₀₀₀ ) at a magnetic field strength of 79.6 kA / m after magnetic saturation is preferably 3.77 to 37.7 μWb / cm ³ . In order to achieve higher image quality, it is more preferably 12.6 to 31.4 Wb / cm ³ . When the magnetization intensity is greater than 37.7 μWb / cm ^3, it becomes difficult to obtain a high-quality toner image. On the other hand, when it is less than 3.77 Wb / cm ³ , the magnetic binding force is also reduced, so that carrier adhesion is likely to occur.

  When a two-component developer is prepared by mixing the toner used in the present invention and a magnetic carrier, the mixing ratio is such that the toner concentration in the developer is 2 to 15% by mass, preferably 4 to 13% by mass. Usually good results are obtained.

  Each measurement method used in the present invention will be described below.

(1) Measurement of toner particle size distribution and calculation of number variation coefficient The toner particle size distribution can be measured by various methods. In the present invention, it is preferable to use a Coulter counter.

  Using Coulter Counter Multisizer Type I or Type II or Type IIe (manufactured by Coulter, Inc.) as a measuring device, connect an interface (manufactured by Nikkiki) that outputs number average distribution and volume average distribution and a general personal computer. A 1% NaCl aqueous solution is prepared as an electrolyte using special grade or first grade sodium chloride.

  As a measurement method, 1.5 ml of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 130 ml of the electrolytic aqueous solution, and 10 mg of a measurement sample is further added. The electrolyte solution in which the sample is suspended is dispersed for about 2 minutes with an ultrasonic disperser, and the particle size distribution of particles of 2 to 40 μm on the basis of the number using the 100 μm aperture as the aperture by the Coulter Counter Multisizer II type. And then determine various values.

The coefficient of variation in the number distribution is calculated from the following equation.
Coefficient of variation (%) = [S / D1] × 100
[In the formula, S represents a standard deviation in the number distribution of toner particles, and D1 represents a number average diameter (μm) of toner particles. ]

(2) Evaluation of wet toner particle cleaning state The cleaning state was evaluated by the amount of the dispersion stabilizer remaining on the wet toner particle surface. The amount of residual dispersion stabilizer was quantitatively analyzed using a fluorescent X-ray analyzer (RIX3000). The amount of the residual dispersion stabilizer is preferably 180 ppm or less from the viewpoint of chargeability.

(3) Measurement of moisture content The moisture content in the present invention is determined by collecting 5 g of wet toner particles in an aluminum dish, precisely weighing it (A [g]), and leaving it in a dryer set at 105 ° C. for 1 hour. It is a value calculated by the following formula after precise cooling (B [g]) after cooling.
Moisture content [%] = ((A−B) / A) × 100

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but these do not limit the present invention in any way.

[Example 1]
After adding 450 parts by mass of 0.1 mol / liter-Na ₃ PO ₄ aqueous solution to 700 parts by mass of ion-exchanged water and heating to 60 ° C., CLEARMIX CLS-30S (M Technique Co., Ltd.) was used. Stir at 4500 rpm. To this was added 68 parts by mass of a 1.0 mol / liter-CaCl ₂ aqueous solution to obtain an aqueous medium containing a calcium phosphate salt.

on the other hand,
(Monomer) 170 parts by mass of styrene
30 parts by mass of n-butyl acrylate (colorant) C.I. I. Pigment Red 150 10 parts by mass (charge control agent) E-88 (manufactured by Orient Chemical Industries) 2 parts by mass (polar resin) Saturated polyester 15 parts by mass (propylene oxide-modified bisphenol A (2 mol adduct) and terephthalic acid Polycondensate (polymerization molar ratio 10:12), Tg = 68 ° C., Mw = 10000, Mw / Mn = 5.12)
(Release agent) 6 parts by mass of polyethylene wax (Mn = 850, melting point: 107 ° C., penetration at 25 ° C .: 1)
The above material was heated to 60 ° C. and uniformly dissolved and dispersed. In this, 8 parts by mass of a polymerization initiator 2,2′-azobis (2,4-dimethylvaleronitrile) was dissolved to prepare a colorant-containing polymerizable monomer composition.

The polymerizable monomer composition is put into the aqueous medium, and stirred at 4500 rpm for 15 minutes with Claremix in an N ₂ atmosphere at 60 ° C. to granulate the colorant-containing polymerizable monomer composition. did.

  Thereafter, while stirring with a full zone stirring blade (manufactured by Shinko Pantech Co., Ltd.), the temperature was raised to 70 ° C. and reacted for 10 hours. After the completion of the polymerization reaction, saturated steam (pure steam / steam pressure 205 kPa / temperature 120 ° C.) was introduced while stirring was continued with a full zone stirring blade. Twenty minutes after the start of the introduction of saturated steam, the temperature of the contents in the container reached 100 ° C., and a distillation fraction began to come out. Residual monomers were distilled off by obtaining a predetermined amount of fractions, and cooled to obtain a toner particle dispersion.

  After adding hydrochloric acid to the toner particle dispersion to dissolve the calcium phosphate on the surface of the toner particles, a belt filter (modified by Tsukishima Kikai Co., Ltd., modified with a synchro filter) equipped with a compressed aeration mechanism shown in FIGS. And dehydrated and washed under the following conditions to obtain a cake of wet toner particles.

<Operating conditions such as dewatering and washing of belt filter of compressed air mechanism>
Filtration area: 0.15 m ²
Slurry supply amount: 150 kg / hour

Belt speed: Stop time / moving time = 10/1, average 0.7 m / min Wash water amount: 50 kg / hour Vacuum degree: -70 kPa
Seal ventilation roll: As shown in FIG. 2, the gas discharge part is a perforated type roll pressing pressure (seal pressure): 500 kPa.
Ventilation pressure: 400kPa
Squeeze time: 70 seconds (press air ventilation mechanism is installed in the final span and the belt is stopped in the final span for 70 seconds during the 75 seconds)
Aeration time: 60 seconds (60 seconds out of 70 seconds of pressing time)

  The moisture content of the wet toner particles obtained as described above was 20%. Further, when the washing state of the wet toner particle cake at this time was analyzed with the above-mentioned X-ray fluorescence analyzer, the amount of the remaining dispersion stabilizer was 100 ppm, which was satisfactory.

  Thereafter, the wet toner particle cake was crushed and air-dried under the following conditions to obtain toner particles.

<Air dryer drying conditions>
Air dryer (manufactured by Seishin Enterprise Co., Ltd .: flash jet dryer: pipe diameter 0.1016 m)
Blowing temperature: 90 ° C
Blowing air volume: 10m ³ / min
Wet toner particle supply amount: 50 kg / hr

To 100 parts by mass of the toner particles obtained above, 1.0 part by mass of hydrophobic silica having a specific surface area by the BET method of 200 m ² / g was added and mixed with a mixer to obtain a toner. The toner obtained in this example had a weight average particle diameter of 6.8 μm.

<Evaluation of image performance>
The image performance was evaluated by performing a continuous 3000 sheet durability test in an environment of a temperature of 30 ° C. and a humidity of 80%, and measuring fog. The durability test was performed using a Canon color laser printer LBP-2360.

  The fog on the paper was measured using a reflection densitometer (TOKYODENSHOKUCO., REFECTOMETER ODEL TC-6DS manufactured by LTD). That is, when the reflection density worst value of the pudding measured by the reflection densitometer and the subsequent white background is Ds, and the average reflection density value measured by the reflection densitometer of the paper before printing is Dr, the difference between these values ( Ds-Dr) was determined and used as fog on paper. When the amount of fog on the paper was 2% or less, the image was substantially free from fog on the paper, but when it exceeded 2%, the image was blurred with noticeable fog on the paper.

  In this example, an image after 3000 sheets of durability was evaluated, but the level of fog was satisfactory during the durability. The results are summarized in Table 1.

[Example 2]
Under the operating conditions of Example 1, pressing pressure (seal pressure): 900 kPa
Ventilation pressure: 700kPa
Table 1 shows the results of performing the same operations as in Example 1 except that the evaluation was performed.

Example 3
Under the operating conditions of Example 1, pressing pressure (seal pressure): 100 kPa
Ventilation pressure: 10kPa
Table 1 shows the results of performing the same operations as in Example 1 except that the evaluation was performed.

Example 4
Table 1 shows the results of evaluation performed in the same manner as in Example 1 except that the wet toner particle cake was not washed under the operating conditions of Example 1, that is, the amount of washing water was 0 kg / hour. .

Example 5
Table 1 shows the results of evaluation performed in the same manner as in Example 1 except that the sealing ventilated roll in the operating conditions of Example 1 is shown in FIG. Show.

Example 6
Sealed ventilated roll under the operating conditions of Example 1: The result of performing the same operation as in Example 1 except that the roll surface is a roll using a perforated material with a shape without a recess as shown in FIG. Table 1 shows.

Example 7
After adding 450 parts by mass of 0.1M Na ₃ PO ₄ aqueous solution to 700 parts by mass of ion-exchanged water and heating to 60 ° C., using Claremix CLS-30S (M, Technic Co., Ltd.) at 4500 rpm. And stirred. To this, 68 parts by mass of 1.0 M CaCl ₂ aqueous solution was added to obtain an aqueous medium containing calcium phosphate.

on the other hand,
(Monomer) 170 parts by mass of styrene
n-Butyl acrylate 40 parts by mass (colorant) Silane coupling agent-treated magnetic body (see “Production of magnetic body” below)
180 parts by mass (charge control agent) E-88 (manufactured by Orient Chemical Co., Ltd.) 2 parts by mass (polar resin) saturated polyester 15 parts by mass (propylene oxide-modified bisphenol A (2 mol adduct) and polycondensate of terephthalic acid (Polymerization molar ratio 10:12), Tg = 68 ° C., Mw = 10000, Mw / Mn = 5.12)
(Release agent) 5 parts by mass of polyethylene wax (Mn = 850, melting point: 107 ° C., penetration at 25 ° C .: 1)
The above-mentioned formulation was heated to 60 ° C. and uniformly dissolved and dispersed. Into this, 8 parts by mass of a polymerization initiator tert-butyl peroxypivalate was dissolved to prepare a magnetic substance-containing polymerizable monomer composition.

The above-mentioned colorant-containing polymerizable monomer composition is put into the aqueous medium, and stirred at 4500 rpm for 15 minutes with Claremix at 60 ° C. in an N ₂ atmosphere, and the magnetic substance-containing polymerizable monomer composition. Granulated.

  Then, while stirring with a full zone stirring blade (made by Shinko Pantech Co., Ltd.), the temperature was raised to 70 ° C. and reacted for 8 hours. After the completion of the polymerization reaction, saturated steam (pure steam / steam pressure 205 kPa / temperature 120 ° C.) was introduced while stirring was continued with a full zone stirring blade. Twenty minutes after the start of the introduction of saturated steam, the temperature of the contents in the container reached 100 ° C., and a distillation fraction began to come out. Residual monomers were distilled off by obtaining a predetermined amount of fractions, and cooled to obtain a magnetic toner particle dispersion.

  Thereafter, magnetic toner particles were obtained in the same manner as in Example 1 except that the slurry supply rate was 200 kg / hour.

The obtained magnetic toner particles 100 parts by mass and a silica fine powder (BET specific surface area 180 m ² / g) having a number average primary particle size of 12 nm were treated with hexamethyldisilazane and then treated with silicone oil, and the treated BET 1.0 part by mass of hydrophobic silica fine powder (number average primary particle size 12 nm) having a value of 120 m ² / g was mixed with a Henschel mixer (Mitsui Miike Chemical Co., Ltd.) to obtain a magnetic toner. The toner obtained in this example had a weight average particle diameter of 6.4 μm.

-Manufacture of magnetic materials-
In aqueous ferrous sulfate solution, 1.0 to 1.1 equivalents of caustic soda solution with respect to iron element, 1.5 mass% sodium hexametaphosphate in terms of phosphorus element with respect to iron element, silicon element with respect to iron element An aqueous solution containing ferrous hydroxide was prepared by mixing 1.5 mass% sodium silicate in terms of conversion.

  While maintaining the aqueous solution at pH 9, air was blown and an oxidation reaction was performed at 80 to 90 ° C. to prepare a slurry liquid for generating seed crystals.

  Subsequently, after adding ferrous sulfate aqueous solution so that it may become 0.9-1.2 equivalent with respect to the original alkali amount (sodium component of caustic soda) to this slurry liquid, the slurry liquid is maintained at pH 8 and air is supplied. The oxidation reaction was promoted while blowing to obtain a slurry liquid containing magnetic iron oxide. This slurry was filtered and washed. Next, this water-containing slurry was re-dispersed in another aqueous medium, and then the pH of the re-dispersed liquid was adjusted to about 4.5, and n-hexyltrimethoxysilane was added to 100 parts by mass of magnetic iron oxide with sufficient stirring. Then, 2.0 parts by mass was added to perform hydrolysis. Thereafter, the pH of the dispersion was adjusted to about 10, a condensation reaction was performed, and a coupling treatment was performed. The produced hydrophobic magnetic fine particles were washed, filtered and dried by a conventional method, and the resulting particles were crushed. The obtained magnetic fine particles had a volume average particle size of 0.20 μm.

<Evaluation of image performance>
The image performance was evaluated by performing a continuous 5000 sheet durability test in an environment of a temperature of 30 ° C. and a humidity of 80%, and measuring fog. The durability test was performed using a Canon LBP-1760.

  The fog on the paper was measured using a reflection densitometer (TOKYODENSHOKUCO., REFECTOMETER ODEL TC-6DS manufactured by LTD). That is, when the reflection density worst value of the pudding measured by the reflection densitometer and the subsequent white background is Ds, and the average reflection density value measured by the reflection densitometer of the paper before printing is Dr, the difference between these values ( Ds-Dr) was determined and used as fog on paper. When the amount of fog on the paper was 2% or less, the image was substantially free from fog on the paper, but when it exceeded 2%, the image was blurred with noticeable fog on the paper.

  In this example, the image after the endurance of 5000 sheets was evaluated, but it was a level of fog without any problem during the endurance. The results are summarized in Table 1.

[Comparative Example 1]
Under the dehydration / washing conditions of Example 1, the same operation as in Example 1 was performed without operating the squeezing aeration mechanism by the roller. As a result, the moisture content of the wet toner particles was very high at 36%, so that the wet toner particle supply amount of the air dryer was lowered to 25 kg / hr to perform drying. Others were evaluated in the same manner as in Example 1. The results are shown in Table 1.

[Comparative Example 2]
The same operation as in Example 8 was performed without depressurizing and aerating mechanism using a roller in dehydrating and washing the magnetic toner particles of Example 8. As a result, since the moisture content of the wet toner particles was very high at 37%, the wet toner particle supply amount of the air dryer was lowered to 25 kg / hr, and drying was performed. Others were evaluated in the same manner as in Example 1. The results are shown in Table 1.

[Comparative Example 3]
The toner particle dispersion obtained in the same manner as in Example 1 is sent to a belt filter having a squeezing roll without the ventilation mechanism of the mode shown in FIG. 6, and the same operation as in Example 1 is performed except for the following conditions. Went.
Upper pressing roll: Fixed to be rotatable.
Lower pressing roll: Driven to be rotatable and pressurizable to the upper pressing roll.
Lower pressing roll pressing pressure: 0.3 Mpa

  As a result, the moisture content of the wet toner particles was very high at 33%. Therefore, the wet toner particle supply amount of the air dryer was reduced to 30 kg / hr, and drying was performed. Others were evaluated in the same manner as in Example 1. The results are shown in Table 1.

It is the belt filter schematic which comprised the seal | sticker ventilation roll which is the pressing ventilation mechanism concerning this invention. It is the schematic of the seal | sticker ventilation roll concerning this invention. (The shape with a recess and the gas discharge part is a perforated type roll) It is the schematic of the seal | sticker ventilation roll concerning this invention. (Because it has a concave shape, the gas discharge part is a nozzle type roll) It is the schematic of the seal | sticker ventilation roll concerning this invention. (Roll with no recess and roll surface made of perforated material) It is the schematic of the contact-and-separation mechanism of the seal ventilation roll concerning this invention. It is explanatory drawing which shows an example of the other conventional solid-liquid separation and dehydration apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Guide roll 2 Filter cloth 3 Feed port 4 Vacuum tray 5 Cake 6 Filter cloth washing apparatus 7 Cake washing apparatus 8 Seal ventilation roll mechanism 9 Seal ventilation roll recessed part 10 Seal ventilation roll seal part 11 Compressed gas discharge part 12 Contact and separation Mechanism 13 Compressed gas inlet 40 Upper pressing roll 41 Lower pressing roll

Claims (11)

A vacuum tray connected to a vacuum pump is disposed below the annular filter cloth that is driven to drive, and the aqueous dispersion medium in which toner particles produced in the aqueous dispersion medium are dispersed is supplied onto the filter cloth. In the toner particle manufacturing apparatus including a filter cloth traveling belt filter that collects the aqueous dispersion medium in a vacuum tray by a vacuum pump and filters the toner particles as a cake on the filter cloth.
In the state which has a gas discharge part for discharging gas, and sealed gas leak by being pressed on the filter cloth or the cake, or both, from the gas discharge part, the filter cloth, the cake, or both An apparatus for producing toner particles, comprising an elastic and rotatable seal ventilation roll that discharges the gas to the pressing side of the cake to perform aeration and dehydration of the cake . The gas discharge section is provided in a plurality of systems in the circumferential direction of the seal vent roll , and when performing ventilating dehydration , the seal vent roll is pressed against the filter cloth or the cake or both of them . the strains that are installed Te gas outlet section only by selecting apparatus for producing toner particles according to claim 1, characterized in that for discharging the gas. It said seal vent roll has a plurality of rolls recesses, apparatus for producing toner particles according to claim 1 or 2, characterized in that it comprises a gas discharge portion to the roll recess. The discharged gas from the gas ejection out portion in the space in the roll recess, apparatus for producing toner particles according to any one of claims 1 to 3, characterized in that the ventilation dewatering the cake. The gas discharge portion has a perforation, apparatus for producing toner particles according to claim 3 or 4, characterized in that for discharging the gas from the perforations. Said seal vent roll, the filter cloth traveling type traveling movement and tuning of the filter cloth of the belt filter, in any one of claims 1 to 5, characterized in that the rotation movement at the same speed as the filter cloth The toner particle production apparatus described. 7. The method for producing toner particles according to claim 1, wherein the running motion of the filter cloth of the filter cloth running belt filter is an intermittent movement . Said seal vent roll, in conjunction with the intermittent movement of the filter cloth, the filter cloth or the cake or it is possible to adjust the pressure for pressing both of these, the sealing vent roll the at the vent dehydration The pressure P1 pressed against the filter cloth or the cake or both is:
100 (kPa) ≦ P1 ≦ 900 (kPa)
The toner particle manufacturing apparatus according to claim 7 , wherein The seal ventilation roll can adjust the pressure that presses against the filter cloth or the cake or both of them in conjunction with the intermittent movement of the filter cloth, and the seal ventilation roll is operated when the filter cloth is running. The pressure P2 pressed against the filter cloth or the cake or both is:
0 (kPa) ≦ P2 ≦ 200 (kPa)
The toner particle manufacturing apparatus according to claim 7 , wherein the toner particle manufacturing apparatus is a toner particle manufacturing apparatus. A toner particle manufacturing method using the toner particle manufacturing apparatus according to claim 1 . The gas is a compressed gas, and the pressure P3 of the compressed gas is:
10 (kPa) ≦ P3 ≦ 700 (kPa)
The method for producing toner particles according to claim 10, wherein:

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