JP6107169B2 - Image forming apparatus - Google Patents

Description

The present invention relates to an ultra-high-speed image forming apparatus having a system speed of 400 to 2000 mm / sec, an elastic intermediate transfer belt type transfer device, an external additive and a charge control agent, and surface-treated toner. The present invention relates to an image forming apparatus provided.

In recent years, high speed and high image quality have been generally demanded in the electrophotographic industry.
However, the image quality deteriorates as the image forming speed, that is, the system speed of the so-called image forming apparatus increases, and the blurring, which is one of the factors that greatly affect the image quality, deteriorates. Technology to make it necessary.

When an electrophotographic image forming apparatus such as a laser printer or a copying machine prints on an uneven recording material such as non-smooth paper or an envelope, a toner image is secondarily transferred from the intermediate transfer member to the recording material. In some cases, a part of the toner image is not transferred and white spots occur, and so-called blur occurs.
The main causes of this blur are the unevenness of the recording material, which reduces the adhesion between the intermediate transfer member and the recording material, and severely deteriorates the toner, increasing the adhesion of the toner base particles. The toner fluidity is low and the charging stability of the toner is poor.

Therefore, in order to increase the system speed and not to reduce the quality of the blurred image, the degree of adhesion between the intermediate transfer member and the recording material is increased, and the adhesion of the toner base particles is kept low, and the toner fluidity is reduced. It is necessary to increase the charging stability of the toner.
As a countermeasure, in order to increase the degree of adhesion between the intermediate transfer member and the recording material, a method using an elastic body on the surface as the intermediate transfer member (see Patent Documents 1 and 2) can be considered. However, when an endless belt made of a rubber elastic body is used as the intermediate transfer body, the image on the intermediate transfer body expands and contracts due to fluctuations in the tension of the endless belt, and in particular, color images cause color misregistration. There is a problem. In this connection, the degree of adhesion between the intermediate transfer member and the recording material when the system linear speed is increased is not optimized, and it is considered that the color misregistration of the color image is further deteriorated.

Further, in order to transfer a high-quality toner image formed on the surface of the photosensitive member to the transfer member without disturbing it, a method of controlling the surface resistance of the intermediate transfer member can be considered (see Patent Documents 1 and 2).
However, the degree of adhesion between the intermediate transfer member and the recording material when the system linear speed is increased is not optimized, and it is considered that the color misregistration of the color image is further deteriorated.

  Japanese Patent Application Laid-Open No. 2006-308979 of Patent Document 3 discloses a toner layer formed on an intermediate transfer body in front of a secondary transfer portion on the upstream side in the rotation direction of the intermediate transfer body in order to prevent transfer image defects. Although an image forming apparatus provided with means for pressing is disclosed, this technique is not related to the intermediate transfer body itself.

  In Japanese Patent Application Laid-Open No. 2007-4081 of Patent Document 4, a photoconductive property is provided on a substrate having a high Young's modulus (2500 to 8000 MPa) with little displacement of the belt due to stress, without or via an elastic intermediate layer. However, this technique is not intended to improve the adhesion between the intermediate transfer member and the recording material.

  Japanese Patent Laid-Open No. 2008-209848 of Patent Document 5 describes that the volume resistance is in the range of 1 × 10 7 to 1 × 10 11 Ω / □, but this technique is also similar to Patent Documents 1 and 2 above. It is not intended to optimize the degree of adhesion between the intermediate transfer member and the recording material when the system linear velocity is increased.

  Japanese Patent Application Laid-Open No. 2008-268435 of Patent Document 6 describes a color toner in which an external additive containing titanium oxide fine particles having a volume resistance of 105 Ωcm to 1010 Ωcm is applied to the toner particle surface. However, it is not intended to optimize the degree of adhesion between the intermediate transfer member and the recording material when the system linear velocity is increased.

  As described above, the quality of the blurred image can be improved by adopting the method of using an elastic body on the surface as the intermediate transfer member and the method of controlling the surface resistance of the intermediate transfer member. However, in a high-speed system, the technology that can increase the adhesion between the intermediate transfer member and the recording material and keep the adhesion of the toner base low has not been optimized, and the quality of the blurred image is not improved. Deteriorating becomes a problem.

  The present invention has been made in view of the above background, and an object of the present invention is to provide an image forming apparatus that has an effect of improving a blurred image and can improve image quality.

As described above, in an image forming apparatus of an ultra-high speed machine (400-2000 mm.sec), a blur occurs on various papers including uneven paper. The reason is that the toner is not sufficiently transferred from the intermediate transfer belt to the concave portion on the paper because the linear velocity is high, so that the toner is partially removed and the image looks blurry. As a result of intensive studies on this problem, the present inventors have found that such toner transfer insufficiency is due to a complex cause consisting of several factors, and a specific intermediate transfer belt. It has been found that a selective combination of toner and a specific toner is extremely effective for solving the problem.
Thus, the above object is achieved by the present invention including the “image forming apparatus” described in the following items (1) to (10).
(1) “In an image forming apparatus having an endless intermediate transfer belt for conveying a sheet-like medium carrying a toner image and having a system speed of 400 to 2000 mm / sec, the intermediate transfer belt is at least from a substrate. A laminated structure in which spherical resin particles are arranged in the surface direction on the surface, and a second layer made of an elastic body formed with an uneven shape is sequentially laminated, and the intermediate transfer belt has an electric resistance adjustment. The intermediate transfer belt has a surface resistance of 1 × 10 ⁸ [Ω / □] to 1 × 10 ¹³ [Ω / □] and a volume resistance of 1 × 10 ⁶ [Ω · cm] to It is adjusted to be in the range of 1 × 10 ¹² [Ω · cm], and the second layer made of the elastic body has a thickness in the range of 200 [μm] to 2000 [μm]. The volume average particle diameter of the spherical resin particles used for the layer is 0.5 [μm] to 5.0 [μm]. Yes,
The toner is composed of base particles formed of colored particles obtained by emulsifying or dispersing an oil phase of a stock solution containing a toner material in a solvent in an aqueous medium, and then granulated by desolvation. Contains at least a charge control agent and has at least two kinds of external additives attached to the surface of the base particles. The external additives are inorganic fine particles, polymer fine particles, or polymer particles made of a thermosetting resin. The particle diameter of the external additive is in the range of 2 [nm] to 2 [μm], and the base particles are surface-treated with a fluidizing agent as necessary. An image forming apparatus. "
(2) The above-mentioned (1), wherein the base material in the intermediate transfer belt is a resin material containing at least a polyimide or polyamideimide component or a fluorine-based resin component and an electrical resistance adjusting material. The image forming apparatus according to the item.
(3) “The base material of the intermediate transfer belt of the intermediate transfer belt contains an electric resistance adjusting material, and the surface resistance of the second layer is 1 × 10 ⁸ [Ω / □] to 1 × 10 ¹³ [Ω / □], and the volume resistance of the intermediate transfer belt is adjusted to be in the range of 1 × 10 ⁶ [Ω · cm] to 1 × 10 ¹² [Ω · cm]. The image forming apparatus according to item (1) or (2). "
(4) “The electric resistance adjusting material of the base material of the intermediate transfer belt is selected from the group consisting of carbon black, metal or metal (sub) oxide, and organic ionic onium salt, and the content is The image forming apparatus according to any one of (1) to (3), wherein the total solid content is 0.5 [wt%] to 30 [wt%]. "
(5) “The elastic body of the intermediate transfer belt has a compressive Young's modulus of 0.5 to 80.0 MPa / m ² when any stress is applied in a stress range of ^{3 to} 50 N / mm ^2. The image forming apparatus according to any one of the items (1) to (5).
(6) In any one of the above items (1) to (6), the elastic body of the second layer in the intermediate transfer belt includes a curable resin material at least partially. The image forming apparatus described. "
(7) “The large particle size silica is used in at least a part of the external additive, and the large particle size silica has a particle size of 25 [nm] to 270 [nm]. ) To (6).
(8) “A large particle size silica is used in at least a part of the external additive, and the coverage of the large particle size silica on the base particles is 5% to 45%. The image forming apparatus according to any one of (1) to (7).
(9) “Large particle size silica, small particle size silica, and titanium oxide are used as the external additive, and the total use ratio thereof is 0.1 [weight] with respect to 100 [parts by weight] of the toner. Parts] to 12 [parts by weight], and the ratio of (large particle size silica + small particle size silica) / titanium oxide is 1 to 10, in the above items (1) to (8) Any one of the image forming apparatuses. "
(10) Items (1) to (1), wherein the charge control agent is used in an amount of 0.2 [parts by weight] to 5 [parts by weight] with respect to 100 [parts by weight] of the toner. The image forming apparatus according to any one of items 9). "

As will be understood from the following detailed and specific description, in the present invention, (i) the intermediate transfer belt base material and elastic surface particles are optimized to increase the adhesion between the intermediate transfer belt and the recesses on the paper. (Ii) In addition, at least two kinds of external additives are used in combination as an external additive to give the toner functions of low adhesion, high fluidity, and Q / M stability. Due to the low adhesion and high fluidity, the dissociation property of the toner from the intermediate transfer belt increases even if the linear velocity is high, and the toner is easily transferred to the concave portion on the paper. In addition, since Q / M affects the transfer rate, an extremely excellent effect that the toner transfer rate from the intermediate transfer belt to the concave portion on the paper is stabilized by Q / M stability is exhibited.
That is, in the present invention, even in an image forming apparatus having a system speed of 400 to 2000 mm / sec, there is an effect of improving a blurred image and image quality can be improved.

1 is a schematic diagram showing an outline of an image forming apparatus according to the present invention. FIG. 3 is a schematic diagram of a layer configuration example of an intermediate transfer belt in the present invention. The schematic diagram of the apparatus for apply | coating and fixing the powder particle in this invention. The schematic diagram of the apparatus for coating the base material and elastic body in this invention. The schematic diagram which showed the state when the sensory evaluation of the blur in this invention is (double-circle) and (circle). The schematic diagram which showed the state when the sensory evaluation of the blur in this invention is (triangle | delta) and x.

[Image forming equipment]
FIG. 1 is a schematic diagram showing an example of an image forming apparatus equipped with an intermediate transfer belt unit (intermediate transfer member) according to the present invention.
In the image forming apparatus according to the present embodiment, image forming apparatuses 10Y (yellow), 10C (cyan), 10M (magenta), and 10K (black) for four colors, which are image carrier units, correspond to images. An optical unit 20, an intermediate transfer body unit 30, a paper feed unit 40, a fixing unit 50, and the like serving as exposure means capable of irradiating laser light are detachably attached to the forming station.
Each of the image forming apparatuses 10Y, 10C, 10M, and 10K has the same structure. Each of the image forming apparatuses 10Y, 10C, 10M, and 10K has a photosensitive drum 12 as an image carrier, and a charging device 13 that charges the photosensitive drum as a process unit that operates on the photosensitive drum. A cleaning device 14 for removing the developer remaining on the photosensitive drum 14 is integrally formed, and a developing device 15 for developing a latent image formed on the photosensitive drum is connected to the cleaning device 14. Each image forming device is configured to be detachable from the image forming apparatus main body in the opening / closing direction of the opening / closing face plate (to be described later) (rotational axis direction of the photoreceptor).

The intermediate transfer body unit 30 is formed on a transfer belt 31 as an intermediate transfer body, four rollers 32, 33, 34-1 and 34-2 that rotatably support the transfer belt 31, and each photosensitive drum 12. A primary transfer roller 35 that transfers the toner image to the transfer belt 31 and a secondary transfer roller 36 that further transfers the toner image transferred onto the transfer belt 31 to the recording paper P are provided.
The paper feed unit 40 includes a paper feed roller 43 and a registration roller 44 that convey the recording paper P from the paper feed cassette 41 or the manual paper feed tray 42 to the secondary transfer region.
The fixing unit 50 includes a fixing roller 51 and a pressure roller 52, and performs fixing by applying heat and pressure to the toner image on the recording paper P.
In the above configuration, first in the first color yellow image forming device 10Y, after the photosensitive drum 12 is uniformly charged by the charging device 13, the latent image is developed by the developing device 15 by the laser light emitted from the optical unit 20. Development is performed to form a toner image.

The toner image formed on the photosensitive drum 12 is transferred onto the transfer belt 31 by the action of the primary transfer roller 35. After completion of the primary transfer, the photosensitive drum 12 is cleaned by the cleaning device 14 to prepare for the next image formation. The residual toner collected by the cleaning device 14 is stored in a waste toner collection bottle (not shown) installed in the take-out direction of the image forming device (rotational axis direction of the photosensitive drum). It is detachable from the main body of the image forming apparatus so that it can be replaced when the waste toner collecting bottle is full.
A similar image forming process is performed in each of the image forming apparatuses 10C, 10M, and 10K for C, M, and K to form toner images of the respective colors, which are sequentially transferred to the previously formed toner images.
On the other hand, the recording paper P is conveyed to the secondary transfer region by the paper feed cassette 41 or the manual paper feed tray 42, and the toner image formed on the transfer belt 31 by the action of the secondary transfer roller 36 is transferred to the recording paper P. Is done. The recording paper P to which the toner image has been transferred is conveyed to the fixing unit 50, where the toner image is fixed at the nip portion between the fixing roller 51 and the pressure roller 52 of the fixing unit 50, and the discharge tray 55 is discharged by the discharge roller 55. The paper is discharged.
In order to supply new toner to each of the image forming apparatuses 10Y, 10C, 10M, and 10K, the toner bottles 57Y, 57C, 57M, and 57K are rotated and the toner is conveyed through the pipes.

[Intermediate transfer belt]
FIG. 2 shows an example of a layer structure of an intermediate transfer member (intermediate transfer belt) which is one of the main parts of the present invention. However, it is not limited to this configuration. As the configuration of the intermediate transfer belt of this example, a flexible elastic body 31-2 is laminated on a rigid base material 31-1 that can obtain relatively flexibility, and the outermost surface of the elastic body 31-2. Is formed with a layer of spherical resin particles 31-3.
However, in the present invention, between the base material and the elastic layer, for example, for the purpose of improving the adhesion between the two, or for the purpose of adjusting the electrical resistance and capacitance of the entire intermediate transfer belt, An intermediate layer may be provided.

(Base material)
First, the base material 31-1 will be described. Examples of the constituent material include a material containing a filler (or additive) for adjusting electric resistance in the resin, that is, a so-called electric resistance adjusting material. As such a resin, from the viewpoint of heat resistance and flame retardancy, for example, a fluorine-based resin such as PVDF, ETFE, a polyimide resin or a polyamide-imide resin is preferable, and mechanical strength (high elasticity) and heat resistance are preferred. Therefore, a polyimide resin or a polyamideimide resin is particularly preferable.
Examples of the electrical resistance adjusting material include a metal oxide, carbon black, an ionic conductive agent, and a conductive polymer material.

  Examples of the metal oxide include zinc oxide, tin oxide, titanium oxide, zirconium oxide, aluminum oxide, and silicon oxide. Moreover, in order to improve dispersibility, the metal oxide may be subjected to surface treatment in advance.

  Examples of carbon black include ketjen black, furnace black, acetylene black, thermal black, and gas black.

  Examples of the ionic conductive agent include tetraalkylammonium salts, trialkylbenzylammonium salts, alkylsulfonates, alkylbenzenesulfonates, alkyl sulfates, glycerol fatty acid esters, sorbitan fatty acid esters, polyoxyethylene alkylamines, polyoxyethylene fatty acids. Alcohol ester, alkyl betaine, lithium perchlorate, etc. are mentioned, and these may be used in combination.

The electrical resistance adjusting material in the present invention is not limited to the above exemplary compounds.
In addition, the coating liquid containing at least the resin component in the method for producing the intermediate transfer belt of the present invention may further include additives such as a dispersion aid, a reinforcing material, a lubricant, a heat conduction material, and an antioxidant as necessary. You may contain.

The electric resistance adjusting material contained in the intermediate transfer belt is preferably 1 × 10 ⁸ [Ω / □] to 1 × 10 ¹³ [Ω / □] in surface resistance and 1 × 10 ⁶ [Ω · cm in volume resistance. ] To 1 × 10 ¹² [Ω · cm], but it is necessary to select and add an amount in a range where the molded film is brittle and does not easily break from the viewpoint of mechanical strength.

  That is, the electrical properties (surface resistance and volume resistance) and mechanical strength using a coating liquid in which the blending of the resin component (for example, polyimide resin precursor or polyamideimide resin precursor) and the electrical resistance adjusting material is appropriately adjusted. It is preferable to manufacture and use an intermediate transfer belt having a good balance.

  In the case of carbon black, the content of the electric resistance adjusting material in the present invention is 10 [wt%] to 25 [wt%], preferably 15 [wt%] to 20 in the total solid content in the coating liquid. [Wt%]. The content in the case of a metal oxide is 1 [wt%] to 50 [wt%], preferably 10 [wt%] to 30 [wt%] of the total solid content in the coating liquid. If the content is less than the range of the respective electric resistance adjusting material, the effect is not sufficiently obtained, and if the content is more than the respective range, the mechanical strength of the intermediate transfer belt is lowered, and the actual use Not preferable.

(Elastic body)
Next, the elastic body 31-2 laminated on the base material 31-1 will be described.
As a material constituting the elastic body 31-2, a material such as a resin, an elastomer, or a rubber can be used. However, a material having sufficient flexibility (elasticity) to sufficiently exhibit the effects of the present invention is used. It is preferable to use an elastomer material or a rubber material.

  Examples of the elastomer material include thermoplastic elastomers such as polyester, polyamide, polyether, polyurethane, polyolefin, polystyrene, polyacryl, polydiene, silicone-modified polycarbonate, and fluorine copolymer. . Examples of thermosetting include polyurethane, silicone-modified epoxy, and silicone-modified acrylic.

  Examples of the rubber material include isoprene rubber, styrene rubber, butadiene rubber, nitrile rubber, ethylene propylene rubber, butyl rubber, silicone rubber, chloroprene rubber, acrylic rubber, chlorosulfonated polyethylene, fluorine rubber, urethane rubber, and hydrin rubber. . It is more preferable that these have been subjected to at least one part curing treatment.

  A material capable of obtaining performance is appropriately selected from the various elastomers and rubbers. In particular, it is preferable to select a soft material as much as possible in order to follow the surface state of a paper such as a resack paper having irregularities in the surface properties of the paper as a transfer material.

  In the present invention, in order to form a spherical resin particle layer on the surface of this material, a thermosetting material is preferable to a thermoplastic material. The thermosetting material is excellent in adhesiveness with the resin particles due to the effect of the functional group contributing to the curing reaction, and can be reliably fixed. Vulcanized rubber is likewise preferred.

  To the selected material, a resistance adjusting agent for adjusting electrical characteristics, a flame retardant for obtaining flame retardancy, and materials such as an antioxidant, a reinforcing agent, a filler, and a vulcanization accelerator as necessary. Mixing appropriately included.

  As the resistance adjuster for adjusting the electrical characteristics, the above-mentioned various materials can be applied. However, since carbon black, metal oxide, and the like impair flexibility, it is preferable to suppress the use amount, and the ionic conductive agent and the conductive agent are used. It is also effective to use a functional polymer. Moreover, you may use these together.

As the resistance value of the elastic body 31-2, the surface resistance is 1 × 10 ⁸ [Ω / □] to 1 × 10 ¹³ [Ω / □], and the volume resistance is 1 × 10 ⁶ [Ω · cm] to 1 × 10. It is preferable to adjust so that it may become ¹² [ohm * cm].

  The thickness of the elastic body 31-2 is preferably about 200 [μm] to 2 [mm]. If the film thickness is thin, the followability to the surface properties of the transfer medium and the effect of reducing the transfer pressure are low, which is not preferable. On the other hand, if the film thickness is too thick, the film will be heavier and will bend and become unstable, and cracks are likely to occur due to bending at the roller curvature to stretch the belt. Therefore, it is not preferable.

(Spherical resin particles attached to the surface)
Next, the spherical resin particles 31-3 formed on the surface of the elastic body 31-2 will be described.
The material is not particularly limited, and examples thereof include spherical particles mainly composed of resins such as acrylic resin, melamine resin, polyamide resin, polyester resin, silicone resin, and fluororesin. Further, the surface of particles made of these resin materials may be subjected to surface treatment with a different material. The resin particles referred to here include a rubber material having higher hardness. For example, a structure in which the surface of spherical particles made of a rubber material is coated with a hard resin is also applicable. The spherical resin particles 31-3 may be hollow or porous.

  Of the above-described resins, silicone resin particles are most preferred as having high lubricity and high function capable of imparting releasability and abrasion resistance to the toner.

  As the spherical resin particles 31-3, the above-described resin is used, and the spherical resin particles 31-3 are preferably particles formed in a spherical shape by a polymerization method or the like.

The spherical resin particles 31-3 preferably have a volume average particle size of 0.5 [μm] to 5.0 [μm] and are monodisperse with a sharp distribution. When the volume average particle size is 0.5 [μm] or less, the effect of transfer performance due to the particles cannot be sufficiently obtained. On the other hand, when the volume average particle size is 5.0 [μm] or more, the surface roughness becomes large. In addition, since the gap between the particles becomes large, there arises a problem that the toner cannot be transferred well or the cleaning is poor. Furthermore, since the spherical resin particles 31-3 are often insulative, if the volume average particle size is too large, the charged potential remains due to the spherical resin particles 31-3, and an image resulting from the accumulation of this potential during continuous image output. There is also a problem that disturbance occurs.
Such an elastic body of the intermediate transfer belt according to the present invention is applied with any stress within a stress range of ^{3 to} 50 N / mm ^{2 in} consideration of a nip pressure range at the time of toner image transfer in the image forming apparatus of the present invention. It is preferable that the compression Young's modulus at the time is 0.5 to 80.0 MPa / m ² .

(Belt manufacturing method)
FIG. 4 is a schematic view of an apparatus for applying a substrate and an elastic body in the present invention. An example of a method for producing the belt having the above-described configuration of the present invention will be described.

First, a method for producing a substrate will be described.
A method for producing a substrate using the coating liquid containing at least the resin component of the present invention, that is, the coating liquid containing the polyimide resin precursor or the polyamideimide resin precursor will be described.
The substrate made of polyimide resin or polyamideimide resin is coated on the surface of the cylindrical support (mold) with the precursor liquid by spiral coating with a nozzle or dispenser, or die coating with a wide die, or roll coating using a coating roll. It can be applied by, for example. Here, roll coating will be described. Coating can be performed by an apparatus as shown in FIG. A is a paint pan for storing the defoamed precursor liquid that is a paint, C is an application roller for continuously pumping up the paint from the paint pan A, and D is the thickness of the paint pumped up continuously. Is a regulating roller for adjusting the thickness of the coating roller C to a predetermined coating thickness, and E is a cylindrical support for transferring the coating material (coating film) having a predetermined thickness from the coating roller C to be attached. (Mold).

First, the precursor paint sufficiently defoamed in advance is poured into the paint pan in the manufacturing apparatus described above. The viscosity of the paint is desirably adjusted to 0.5 to 10 Pa · s with the above-described organic polar solvent. Next, a paint pan in which paint is poured into the lower part of the application roller is approached and immersed in the paint, and the paint is applied to the surface of the application roller at a slow peripheral speed of 10 to 100 mm / sec and pumped upward. Thereafter, the thickness of the paint on the application roller is adjusted by a regulating roller which is installed on the upper part of the application roller and can adjust an arbitrary gap with the application roller. The thickness of the paint to be regulated is preferably about twice the thickness of the paint transferred to the cylindrical core.
Next, while the cylindrical support E is slowly rotated on the application roller C, it is brought close to the coating thickness of the application roller or less. The coating material on the application roller is transferred onto the cylindrical support E that rotates in the same direction as the application roller C (the “clockwise direction” in the direction shown in FIG. 4). A paint having a predetermined film thickness is deposited on E.

  After coating, the solvent in the coating film is evaporated at a temperature of about 80 to 150 ° C. while gradually raising the temperature while rotating the cylindrical support. In this process, it is preferable to efficiently circulate and remove atmospheric vapor (such as a volatilized solvent). When a self-supporting film is formed, the mold is transferred to a heating furnace (firing furnace) capable of high-temperature processing, and the temperature is raised stepwise, and finally high-temperature heat processing (firing is performed at about 250 ° C. to 450 ° C. And sufficiently imidizing or polyimidizing the polyimide resin precursor or the polyamideimide resin precursor.

After sufficiently cooling, the elastic body is subsequently laminated.
The elastic body can be manufactured by using a rubber paint in which rubber is dissolved in an organic solvent, coating and forming on a base material, and then drying and vulcanizing the solvent. As the coating molding method, as with the base material, existing coating methods such as spiral coating, die coating, and roll coating can be applied, but in order to improve uneven transferability, the thickness of the elastic body should be increased. As a coating method for forming a thick film, die coating and spiral coating are excellent. Here, the spiral coating will be described. While rotating the base material in the circumferential direction and continuously supplying rubber paint with a round or wide nozzle, the nozzle is moved in the axial direction of the base material, and the paint is spirally applied on the base material. Work. The coating material spirally coated on the substrate is dried while being leveled by maintaining a predetermined rotation speed and drying temperature.

Then, when sufficiently leveled, as shown in FIG. 3, the powder supply device 61 and the pressing member 62 are installed, and while rotating, the spherical particles are uniformly applied to the surface from the powder supply device 61, and the surface is covered. The hit spherical particles are pressed by the pressing member 62 at a constant pressure. The pressing member 62 removes excess particles while burying the particles in the elastic body.
After forming a uniform particle layer, it is cured by heating at a predetermined temperature for a predetermined time to form an elastic body.
After sufficiently cooling, the entire substrate is removed from the mold to obtain a desired intermediate transfer belt.

[toner]
Hereinafter, toner embodiments to which the present invention is applied will be described.
The toner of the present invention comprises particles (colored particles; referred to as “toner” in the present specification) after emulsifying or dispersing a stock solution (oil phase) of a toner material in an aqueous medium (aqueous phase), and then granulating it by solvent removal. It is preferably composed of base particles formed by “base particles” or simply “base particles”. As an external additive for assisting fluidity, developability and chargeability of the base particles, inorganic fine particles such as large particle size silica, small particle size silica and titanium oxide are preferably used.
The particle diameter of the external additive is preferably 25 [nm] to 2 [μm]. Particularly, the large particle diameter silica has a particle diameter of 25 [nm] to 270 [nm], which is larger than the base particle. The diameter silica coverage is preferably 5 [%] to 45 [%].
The specific surface area of the toner having the base particles by the BET method is preferably ^{20 to} 500 [m ² / g]. These inorganic fine particles use large particle size silica, small particle size silica, and titanium oxide, and the total use ratio thereof is 0.1 [parts by weight] to 12 [parts by weight] with respect to 100 [parts by weight] of the toner. Parts by weight], and the ratio of (large particle size silica + small particle size silica) / titanium oxide is preferably 1-10.

  Specific examples of the inorganic fine particles include, for example, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, tin oxide, silica sand, clay, mica, wollastonite, Examples thereof include diatomaceous earth, chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride. In addition, polymer fine particles, for example, polystyrene obtained by soap-free emulsion polymerization, suspension polymerization, dispersion polymerization, methacrylic acid ester, acrylic acid ester copolymer, polycondensation system such as silicone, benzoguanamine, nylon, thermosetting Polymer particles made of a functional resin may be used.

  The amount of the charge control agent used in the toner of the present invention is determined according to the type of binder resin, the presence or absence of additives used as necessary, the toner production method including the dispersion method, and the like. Although it cannot be limited uniquely, it is generally used in the range of 0.1 to 10 parts by weight with respect to 100 parts by weight of the binder resin. The range of 0.2 to 5 parts by weight is preferable. When the amount exceeds 10 parts by weight, the chargeability of the toner is too high, the effect of the main charge control agent is reduced, the electrostatic attractive force with the developing roller is increased, the flowability of the developer is reduced, and the image density is reduced. Incurs a decline. These charge control agents can be dissolved and dispersed after being melt-kneaded with a masterbatch or resin, and of course, they may be added directly when dissolved or dispersed in an organic solvent in the preparation process of the toner material liquid (oil phase). Alternatively, the matrix particles may be immobilized on the surface after the formation.

  As the charge control agent for the toner of the present invention, known ones can be used. For example, nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxy amines, quaternary ammonium salts (including fluorine-modified quaternary ammonium salts), alkylamides, phosphorus Simple substance or compound, tungsten simple substance or compound, fluorine-based activator, salicylic acid metal salt, metal salt of salicylic acid derivative, and the like. Specifically, Nitronine-based dye Bontron 03, quaternary ammonium salt Bontron P-51, metal-containing azo dye Bontron S-34, oxynaphthoic acid metal complex E-82, salicylic acid metal complex E- 84, E-89 of a phenol-based condensate (manufactured by Orient Chemical Industry Co., Ltd.), TP-302 of a quaternary ammonium salt molybdenum complex, TP-415 (manufactured by Hodogaya Chemical Industry Co., Ltd.), quaternary ammonium Copy charge PSY VP2038 of salt, copy blue PR of triphenylmethane derivative, copy charge of quaternary ammonium salt NEG VP2036, copy charge NX VP434 (manufactured by Hoechst), LRA-901, LR-147 which is a boron complex (Nippon Carlit), copper phthalocyanine, perylene, quinaclide And azo pigments, and other high molecular compounds having a functional group such as a sulfonic acid group, a carboxyl group, and a quaternary ammonium salt.

  As the colorant, known dyes and pigments are used. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide, ocher, yellow lead, titanium yellow, polyazo yellow, oil yellow, Hansa Yellow (GR, A, RN, R), Pigment Yellow L, Benzidine Yellow (G, GR), Permanent Yellow (NCG), Vulcan Fast Yellow (5G, R), Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL , Isoindolinone yellow, bengara, red lead, red lead, cadmium red, cadmium mercury red, antimony red, permanent red 4R, para red, phise red, parachlor ortho nitroaniline red, risor fast scarlet G, Reliant Fast Scarlet, Brilliant Carmine BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thioindigo Red B, Thioindigo Maroon , Oil red, quinacridone red, pyrazolone red, polyazo red, chrome vermilion, benzidine Range, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue (RS, BC), Indigo , Ultramarine, bitumen, anthraquinone blue, fast violet B, methyl violet lake, cobalt violet, manganese violet, dioxane violet, anthraquinone violet, chrome green, zinc green, chromium oxide, pyridiane, emerald green, pigment green B, naphthol green B, Green Gold, Acid Green Lake, Malachite Green Lake, Phthalocyanine Green, Anthraquinone Green, Oxidized Chi Tan, zinc white, lithopone and mixtures thereof. The content of the colorant is usually 1 to 15% by weight based on the toner. Preferably, it is 3 to 10% by weight.

  The toner composed of the base particles granulated by solvent removal after emulsifying or dispersing the stock solution (oil phase) of the toner material in the form of oil droplets in an aqueous medium (aqueous phase) is compared with the pulverized toner. This is a kind of so-called chemical method toner. Chemical toners are obtained by spraying an organic solvent solution in which a toner material is dissolved or dispersed to obtain spherical base particles, so-called completely polymerized toners, and so-called completely polymerized resins synthesized from monomers are used as binder components. To many things. However, as in the present invention, in the case of base particles obtained by a production method using an aqueous phase in which lipophilic fine particles or hydrophobized solid fine particles are dispersed in advance, a stock solution (oil phase) is then added and an appropriate O In the course of the dispersion treatment operation to form the / W type dispersion, the solid fine particles move from the aqueous phase in the oil droplet direction and adhere to the surface. The toner base particles formed by removing the solvent through such a process form a hard shell-like portion composed of the solid fine particles on the surface. Therefore, the external additive added later, even in the case of base particles made of a low-temperature sharp-melt binder resin, maintains the state of adhering to the particle surface during long-term storage without entering the base particles. This is expected to have the effect of improving the fluidity of the base particles and preventing aggregation. Examples of the solid fine particles dispersed in advance in the aqueous phase include resin fine particles and water-treated inorganic fine particles. Use of such solid fine particles is preferable, but is not essential in the present invention.

(Resin fine particles)
As the resin fine particles, any resin can be used as long as it can form an aqueous dispersion, and it may be a thermoplastic resin or a thermosetting resin. Examples thereof include vinyl resins, polyurethane resins, epoxy resins, polyester resins, polyamide resins, polyimide resins, silicon resins, phenol resins, melamine resins, urea resins, aniline resins, ionomer resins, and polycarbonate resins. As the resin, two or more of the above resins may be used in combination.
Of these, vinyl resins, polyurethane resins, epoxy resins, polyester resins, and combinations thereof are preferred because an aqueous dispersion of fine spherical resin particles is easily obtained. For example, vinyl resins are polymers obtained by homopolymerization or copolymerization of vinyl monomers, such as styrene- (meth) acrylic acid ester copolymers, styrene-butadiene copolymers, (meth) acrylic acid-acrylic acid esters. Examples thereof include resins such as a polymer, a styrene-acrylonitrile copolymer, a styrene-maleic anhydride copolymer, and a styrene- (meth) acrylic acid copolymer. The average particle size of the resin fine particles is 5 to 200 nm, preferably 20 to 300 nm. In addition, inorganic compound dispersants such as tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, and hydroxyapatite can also be used.

(Water-treated inorganic fine particles)
Silica, titania, alumina, zinc oxide, tin oxide and the like can be used as the water-repellent treated inorganic fine particles. Among them, the silica fine particles have strong negative chargeability. The titania, alumina, zinc oxide It is fixed by pigment fine particles and stronger Coulomb force than inorganic fine particles having relatively high conductivity such as tin oxide.
As the hydrophobizing agent for fine particles, known ones can be used, for example, silane coupling agents, silylating agents, silane coupling agents having a fluorinated alkyl group, organic titanate coupling agents, aluminum-based agents. Coupling agents, silicone oils, modified silicone oils, and the like are preferable surface treatment agents. Many inorganic fine particles that have been subjected to a hydrophobization treatment are commercially available.

Hereinafter, toner base particles (base particles obtained by emulsifying or dispersing the stock solution (oil phase) of the toner material in the form of oil droplets in an aqueous medium (aqueous phase) and then granulating by solvent removal) in the present invention are described below. explain. The base particles in the present invention are not limited to this, but in order to meet the recent needs for energy saving, high speed, high image quality, etc., those using polyester-based binder resins with low-temperature sharp melt properties Can be. Spherical particles with a small particle size and a small particle size distribution width can be produced. Hereinafter, description will be made by taking polyester base particles as an example.
In the base particles, the colored particles are obtained by dissolving a toner composition containing an active hydrogen group-containing polyester raw material and a polyester resin capable of reacting with active hydrogen groups (hereinafter referred to as prepolymer (A)) in an organic solvent. It is preferable to obtain a solution or dispersion obtained by dispersing in a water-based medium containing resin particles and then reacting the prepolymer (A) with a compound having an active hydrogen group. The toner composition can contain a material of colored particles.
The prepolymer (A) is a polycondensate of polyol (1) and polycarboxylic acid (2), and can be obtained by further reacting a polyester resin having an active hydrogen group with polyisocyanate (3).
Examples of the active hydrogen group in this case include those derived from hydroxyl groups (alcoholic hydroxyl groups and phenolic hydroxyl groups), amino groups, carboxyl groups, mercapto groups, and the like, and alcoholic hydroxyl groups are preferred.

  Examples of the polyol (1) include alkylene glycol (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, etc.); alkylene ether glycol (diethylene glycol, triethylene glycol, Ethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.); alicyclic diols (1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.); bisphenols (bisphenol A, bisphenol F, 4,4′-dihydroxybiphenyls such as bisphenol S and 3,3′-difluoro-4,4′-dihydroxybiphenyl; bis (3-fluoro-4-hydroxyphenyl) Tan, 1-phenyl-1,1-bis (3-fluoro-4-hydroxyphenyl) ethane, 2,2-bis (3-fluoro-4-hydroxyphenyl) propane, 2,2-bis (3,5- Bis (hydroxyphenyl) such as difluoro-4-hydroxyphenyl) propane (also known as tetrafluorobisphenol A), 2,2-bis (3-hydroxyphenyl) -1,1,1,3,3,3-hexafluoropropane ) Alkanes; Bis (4-hydroxyphenyl) ethers such as bis (3-fluoro-4-hydroxyphenyl) ether; Alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adducts of the above alicyclic diols Alkylene oxides of the above bisphenols (ethylene oxide, propylene Oxides, butylene oxides, etc.), etc. Among them, preferred are alkylene glycols having 2 to 12 carbon atoms and alkylene oxide additions of bisphenols, and particularly preferred are additions of alkylene oxides of bisphenols. And a combination of this and an alkylene glycol having 2 to 12 carbon atoms.

  Further, as the trivalent or higher polyol (1), a trivalent or higher polyhydric aliphatic alcohol (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); trivalent or higher phenols (trisphenol PA) , Phenol novolac, cresol novolac, etc.); alkylene oxide adducts of the above-mentioned trihydric or higher polyphenols. In addition, the said polyol can be individual or can use 2 or more types together, and is not limited above.

  Examples of the polycarboxylic acid (2) include alkylene dicarboxylic acids (succinic acid, adipic acid, sebacic acid, etc.); alkenylene dicarboxylic acids (maleic acid, fumaric acid, etc.); aromatic dicarboxylic acids (phthalic acid, isophthalic acid, terephthalic acid, Naphthalenedicarboxylic acid, 3-fluoroisophthalic acid, 2-fluoroisophthalic acid, 2-fluoroterephthalic acid, 2,4,5,6-tetrafluoroisophthalic acid, 2,3,5,6-tetrafluoroterephthalic acid, 5- Trifluoromethylisophthalic acid, 2,2-bis (4-carboxyphenyl) hexafluoropropane, 2,2-bis (4-carboxyphenyl) hexafluoropropane, 2,2-bis (3-carboxyphenyl) hexafluoropropane 2,2′-bis (trifluoromethyl) -4,4′-bifu Nildicarboxylic acid, 3,3′-bis (trifluoromethyl) -4,4′-biphenyldicarboxylic acid, 2,2′-bis (trifluoromethyl) -3,3′-biphenyldicarboxylic acid, hexafluoroisopropylidene Dendiphthalic anhydride, etc.). Of these, preferred are alkenylene dicarboxylic acids having 4 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 20 carbon atoms.

  Furthermore, as polycarboxylic acids having 3 or more valences, aromatic polycarboxylic acids having 9 to 20 carbon atoms (trimellitic acid, pyromellitic acid, etc.), anhydrides of the above aromatic polycarboxylic acids, lower alkyl esters (methyl esters) , Ethyl ester, isopropyl ester, etc.). In addition, the said polycarboxylic acid can be used individually or in combination of 2 or more types, It is not limited to the above.

Regarding the ratio of the polyol (1) and the polycarboxylic acid (2) when synthesizing the polyester resin, the equivalent ratio [OH] / [COOH] of the hydroxyl group [OH] and the carboxyl group [COOH] is usually 2/1. To 1/1, preferably 1.5 / 1 to 1/1, and more preferably 1.3 / 1 to 1.02 / 1.
The peak molecular weight of the polyester resin is usually 1000 to 30000, preferably 1500 to 10000, and more preferably 2000 to 8000. When the peak molecular weight is less than 1000, the heat resistant storage stability may be lowered, and when it exceeds 10,000, the low-temperature fixability may be lowered.

  Examples of the polyisocyanate (3) include aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, etc.); alicyclic polyisocyanates (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.); aromatic Diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α, α, α ′, α′-tetramethylxylylene diisocyanate, etc.); isocyanurates, phenol derivatives, oximes, caprolactams, etc. It may be blocked. In addition, these can use 2 or more types together.

  Regarding the ratio of the polyisocyanate (3) and the polyester resin having an active hydrogen group when synthesizing the prepolymer (A), the equivalent ratio [NCO] of the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester resin having a hydroxyl group is used. ] / [OH] is usually 5/1 to 1/1, preferably 4/1 to 1.2 / 1, and more preferably 2.5 / 1 to 1.5 / 1. When [NCO] / [OH] exceeds 5, the low-temperature fixability may be deteriorated. When it is less than 1, the content of urethane groups and / or urea groups in the modified polyester resin is decreased, and offset resistance is reduced. May decrease.

  The content of the component derived from polyisocyanate (3) in the prepolymer (A) is usually 0.5 to 40% by weight, preferably 1 to 30% by weight, more preferably 2 to 20% by weight. %. When the content is less than 0.5% by weight, the offset resistance may be lowered, and when it exceeds 40% by weight, the low-temperature fixability may be lowered.

  The number of isocyanate groups per molecule of the prepolymer (A) is usually 1 or more, preferably 1.5 to 3, more preferably 1.8 to 2.5. When the number of isocyanate groups is less than 1, the molecular weight of the modified polyester resin is lowered, and offset resistance may be lowered.

In the present invention, amines (B) can be used as an extender and / or a crosslinking agent (second active hydrogen group-containing compound).
As the amines (B), diamine (B1), trivalent or higher polyamine (B2), amino alcohol (B3), amino mercaptan (B4), amino acid (B5), amino groups (B1) to (B5) Examples thereof include blocked amine derivatives (B6).
Examples of the diamine (B1) include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′-diaminodiphenylmethane, tetrafluoro-p-xylylenediamine, tetrafluoro-p-phenylenediamine, etc.); alicyclic diamines ( 4,4′-diamino-3,3′-dimethyldicyclohexylmethane, diaminocyclohexane, isophoronediamine, etc .; aliphatic diamines (ethylenediamine, tetramethylenediamine, hexamethylenediamine, dodecafluorohexylenediamine, tetracosafluorododecylene) Amine) and the like.
Examples of the trivalent or higher polyamine (B2) include diethylenetriamine and triethylenetetraamine.
Examples of amino alcohol (B3) include ethanolamine and hydroxyethylaniline.
Examples of amino mercaptan (B4) include aminoethyl mercaptan and aminopropyl mercaptan.
Examples of the amino acid (B5) include aminopropionic acid and aminocaproic acid.
As the amine derivative (B6) in which the amino group of (B1) to (B5) is blocked, ketimine compounds and oxazoline compounds obtained from (B1) to (B5) and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.) Etc.

Furthermore, a terminator can be used in the extension reaction and / or the cross-linking reaction as necessary, and the molecular weight of the modified polyester resin can be adjusted.
Examples of the terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.), and those obtained by blocking these (ketimine compounds).

  Regarding the ratio of the prepolymer (A) to the amines (B) when the prepolymer (A) and the amines (B) are reacted, the isocyanate group [NCO] of the prepolymer (A) and the amines (B) The equivalent ratio [NCO] / [NHx] of the amino group [NHx] is usually 1/2 to 2/1, preferably 1.5 / 1 to 1 / 1.5, more preferably 1 2/1 to 1 / 1.2. When [NCO] / [NHx] is larger than 2 or smaller than 1/2, the molecular weight of the resulting modified polyester resin is decreased, and the hot offset resistance may be lowered.

The organic solvent that dissolves or disperses the toner composition is preferably volatile with a boiling point of less than 100 ° C., since it can be easily removed later.
Examples of such organic solvents include toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, In addition to water-immiscible solvents such as ethyl acetate, water-miscible solvents such as methyl ethyl ketone and methyl isobutyl ketone can be used, and these can be used alone or in combination of two or more.
Particularly preferred are ester solvents such as methyl acetate and ethyl acetate, aromatic solvents such as toluene and xylene, and halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, chloroform and carbon tetrachloride.
The toner composition components may be dissolved or dispersed at the same time, but are usually dissolved or dispersed individually, and the organic solvents used at that time may be different or the same, but considering the subsequent solvent treatment The same is preferable.

The solution or dispersion of the toner composition preferably has a resin concentration of 40 to 80% by weight. When the resin concentration exceeds 80% by weight, it becomes difficult to dissolve or disperse and the viscosity becomes high and it is difficult to handle. On the other hand, if it is less than 40% by weight, the amount of toner produced is reduced.
When mixing the polyester resin and the prepolymer, they may be mixed in the same solution or dispersion, or may be prepared separately, but considering the solubility and viscosity of each, separate dissolution Alternatively, it is preferable to prepare a dispersion.

  The colorant may be dissolved or dispersed alone, or may be mixed in a polyester resin solution or dispersion. If necessary, a dispersion aid or a polyester resin may be added, or a master batch may be used.

When the wax is dissolved or dispersed as the release agent, or when an organic solvent in which the wax does not dissolve is used, it is used as a dispersion, but the dispersion is prepared by a general method. That is, an organic solvent and wax may be mixed and dispersed with a disperser such as a bead mill.
Further, after mixing the organic solvent and the wax, heating to the melting point of the wax, cooling with stirring, and then dispersing with a disperser such as a bead mill may shorten the dispersion time.
Further, a plurality of waxes may be mixed and used, or a dispersion aid or a polyester resin may be added.

As an aqueous medium, water alone may be used, but a solvent miscible with water may be used in combination.
Examples of the miscible solvent include alcohol (methanol, isopropanol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, Cellsolve (registered trademark) (methylcellsolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.) and the like.
The amount of the aqueous medium used relative to 100 parts by weight of the toner composition is usually 50 to 2000 parts by weight, preferably 100 to 1000 parts by weight. When the amount of the aqueous medium used is less than 50 parts by weight, the dispersion state of the toner composition may be deteriorated. Moreover, when it exceeds 2000 weight part, it is not economical.

When the toner composition solution or dispersion is dispersed in the aqueous medium, it is preferable to disperse the inorganic dispersant or the resin particles in the aqueous medium in advance. Thereby, the particle size distribution can be narrowed and stably dispersed.
As the inorganic dispersant, tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, hydroxyapatite and the like are used.

  Further, as the resin forming the resin particles, any resin can be used as long as it can form an aqueous dispersion, and it may be a thermoplastic resin or a thermosetting resin, For example, vinyl resin, polyurethane resin, epoxy resin, polyester resin, polyamide resin, polyimide resin, silicon resin, phenol resin, melamine resin, urea resin, aniline resin, ionomer resin, polycarbonate resin and the like can be mentioned. These resins may be used in combination of two or more. Among these, since it is easy to obtain an aqueous dispersion of fine spherical resin particles, and because it is easy to obtain fine resin particles that are relatively hard and uniform in particle size, vinyl resins, polyurethane resins, epoxy resins, polyesters Resins and combinations thereof are preferred.

Although the method of manufacturing the aqueous dispersion of resin particles is not particularly limited, the following (a) to (h) can be mentioned.
(A) In the case of a vinyl resin, an aqueous dispersion of resin particles is directly produced by a polymerization reaction such as a suspension polymerization method, an emulsion polymerization method, a seed polymerization method, or a dispersion polymerization method using a monomer as a starting material.
(B) In the case of a polyaddition or condensation resin such as a polyester resin, a polyurethane resin, and an epoxy resin, a precursor (monomer, oligomer, etc.) or a solution thereof is dispersed in an aqueous medium in the presence of a suitable dispersant, After that, the resin particles are cured by heating or adding a curing agent to produce an aqueous dispersion of resin particles.
(C) In the case of polyaddition or condensation resin such as polyester resin, polyurethane resin, epoxy resin, etc., it is preferably a precursor (monomer, oligomer, etc.) or a solution thereof (liquid). ) After a suitable emulsifier is dissolved therein, water is added to carry out phase inversion emulsification.
(D) Resin produced in advance by a polymerization reaction (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) After pulverizing and classifying using a fine pulverizer, resin particles are obtained, and then dispersed in water in the presence of an appropriate dispersant.
(E) A resin solution prepared in advance by a polymerization reaction (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) is sprayed in the form of a mist. Thus, the resin particles are obtained and then dispersed in water in the presence of a suitable dispersant.
(F) A resin solution obtained by dissolving a resin prepared in advance in a polymerization reaction (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) in a solvent. The resin particles are precipitated by adding a solvent or by cooling a resin solution previously dissolved in a solvent by heating, and after removing the solvent to obtain resin particles, in a water-based medium in the presence of an appropriate dispersant. Disperse.
(G) A resin solution prepared in advance by a polymerization reaction (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) is used as an appropriate dispersant. After the dispersion in an aqueous medium, the solvent is removed by heating, decompression or the like.
(H) An appropriate emulsifier is added to a resin solution prepared in advance by a polymerization reaction (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.). After dissolving, water is added and phase inversion emulsified.

In addition, a surfactant or the like may be used as necessary in order to emulsify and disperse the toner composition solution or dispersion in an aqueous medium.
Surfactants include alkylbenzene sulfonate, α-olefin sulfonate, anionic surfactants such as phosphate esters, alkylamine salts, amino alcohol fatty acid derivatives, polyamine fatty acid derivatives, amine salt types such as imidazoline, alkyl Quaternary ammonium salt type cationic surfactants such as trimethylammonium salt, dialkyldimethylammonium salt, alkyldimethylbenzylammonium salt, pyridinium salt, alkylisoquinolinium salt, benzethonium chloride, fatty acid amide derivative, polyhydric alcohol derivative, etc. Nonionic surfactants such as alanine, dodecyl bis (aminoethyl) glycine, bis (octylaminoethyl) glycine, and N-alkyl-N, N-dimethylammonium betaine.
Further, by using a surfactant having a fluoroalkyl group, the effect can be increased in a very small amount.
Examples of the anionic surfactant having a fluoroalkyl group include a fluoroalkyl carboxylic acid having 2 to 10 carbon atoms and a metal salt thereof, disodium perfluorooctanesulfonyl glutamate, 3- [ω-fluoroalkyl (C6 to C11). Oxy] -1-alkyl (C3-C4) sodium sulfonate, 3- [ω-fluoroalkanoyl (C6-C8) -N-ethylamino] -1-propanesulfonic acid sodium, fluoroalkyl (C11-C20) carboxylic acid And metal salts, perfluoroalkyl carboxylic acids (C7 to C13) and metal salts thereof, perfluoroalkyl (C4 to C12) sulfonic acids and metal salts thereof, perfluorooctane sulfonic acid diethanolamide, N-propyl-N- (2 -Hydroxyethyl) perfluorooctance Examples include sulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate, and the like.
Further, as the cationic surfactant, aliphatic quaternary ammonium salts such as aliphatic primary, secondary or tertiary amine acids having a fluoroalkyl group, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, etc. Benzalkonium salt, benzethonium chloride, pyridinium salt, imidazolinium salt and the like.

Further, the dispersed droplets may be stabilized by a polymer protective colloid.
Polymeric protective colloids include acids (acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid, maleic anhydride, etc.); (Meth) acrylic monomer (β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, γ-hydroxypropyl acrylate, γ-hydroxy methacrylate) Propyl, 3-chloro-2-hydroxypropyl acrylate, 3-chloro-2-hydroxypropyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, glycerol monomethacrylate, N-methylolacrylate Rilamide, N-methylol methacrylamide, etc.); vinyl alcohol or ethers with vinyl alcohol (vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, etc.); esters of vinyl alcohol and compounds containing a carboxyl group (vinyl acetate, Vinyl propionate, vinyl butyrate, etc.); acrylamide, methacrylamide, diacetone acrylamide or their methylol compounds; acid chlorides (acrylic acid chloride, methacrylic acid chloride, etc.); those having a nitrogen atom or its heterocyclic ring ( Homopolymers or copolymers such as vinylpyridine, vinylpyrrolidone, vinylimidazole, ethyleneimine, etc .; polyoxyethylenes (polyoxyethylene, polyoxypropylene, polyoxyethylene alkylamine, polyoxy) Propylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonylphenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, polyoxyethylene nonylphenyl ester, etc.); celluloses (methyl cellulose) , Hydroxyethyl cellulose, hydroxypropyl cellulose, etc.) can be used.

  In addition, when using a compound that can be dissolved in an acid or alkali such as calcium phosphate salt as the dispersion stabilizer, the calcium phosphate salt is dissolved from the colored particles by a method such as dissolving the calcium phosphate salt with an acid such as hydrochloric acid and washing with water. Can be removed. In addition, it can be removed by an operation such as enzymatic degradation. When a dispersant is used, it can be used in a state where the dispersant remains on the surface of the colored particles, but it is preferable to remove it by washing from the charged surface of the toner.

  The dispersion method is not particularly limited, and known methods such as a low-speed shear method, a high-speed shear method, a friction method, a high-pressure jet method, and an ultrasonic wave can be applied. In order to make the average particle size of the dispersion 2 to 20 μm, a high-speed shearing method is preferable. When a high-speed shearing disperser is used, the number of rotations is not particularly limited, but is usually 1000 to 30000 rpm, and preferably 5000 to 20000 rpm. The dispersion time is not particularly limited, but in the case of a batch method, it is usually 0.1 to 5 minutes. The temperature at the time of dispersion is usually 0 to 150 ° C. (under pressure), preferably 20 to 80 ° C.

In order to remove the organic solvent from the obtained emulsified dispersion, a method of gradually raising the temperature of the whole system under normal pressure or reduced pressure and evaporating and removing the organic solvent in the droplets can be employed.
It is also possible to spray the emulsified dispersion in a dry atmosphere to remove the organic solvent in the droplets and to evaporate and remove the surfactant.
As the dry atmosphere in which the emulsified dispersion is sprayed, a gas obtained by heating air, nitrogen, carbon dioxide gas, combustion gas, or the like can be used, but various airflows heated to a temperature equal to or higher than the boiling point of the organic solvent are generally used. . At this time, the processing time can be shortened by using a spray dryer, a belt dryer, a rotary kiln or the like.

The amines (B) may be mixed in an organic solvent before dispersing the toner composition in the aqueous medium, or may be added to the aqueous medium.
The time required for the reaction of the prepolymer (A) and the amines (B) is appropriately selected depending on the reactivity of the prepolymer (A) and the amines (B), but is usually 1 minute to 40 hours, preferably Is 1 to 24 hours. The reaction temperature is usually 0 to 150 ° C., preferably 20 to 98 ° C. In addition, a well-known catalyst can be used as needed.

A known method is used for the step of washing and drying the colored particles dispersed in the aqueous medium.
That is, after solid-liquid separation with a centrifuge, a filter press, etc., the obtained toner cake is redispersed in ion-exchanged water at room temperature to about 40 ° C., and if necessary, pH adjusted with acid or alkali, The process of solid-liquid separation is repeated several times. In this way, after removing impurities, surfactants, etc., colored particles (toner base particles) are obtained by drying with an air flow dryer, circulation dryer, vacuum dryer, vibration fluid dryer or the like. At this time, the fine particle component may be removed by centrifugation or the like, and after drying, a desired particle size distribution can be obtained using a known classifier as necessary.

[Mixing of external additives]
Further, in order to enhance the fluidity, storage stability, developability, and transferability of the toner, a general powder mixer can be used to add and mix the external additive to the colored particles. It is preferable to adjust the internal temperature. In order to change the load history applied to the external additive, the external additive may be added midway or gradually. In this case, you may change the rotation speed, rolling speed, time, temperature, etc. of a mixer.
Also, a strong load may be given first, then a relatively weak load, or vice versa. Examples of the mixer include a V-type mixer, a rocking mixer, a Roedige mixer, a Nauter mixer, and a Henschel mixer.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, these examples are intended to facilitate understanding of the present invention and are not intended to limit the present invention. Unless otherwise specified, in each example, “%” and “part” indicate “%” and “part” on a weight basis.

[Example 1]
[Intermediate transfer belt]
A substrate coating solution was prepared as follows, and an intermediate transfer belt substrate 31-1 was produced using this coating solution.

<Preparation of substrate coating solution>
First, carbon black (Special Black 4; Evonik Degussa Co., Ltd.) dispersed in N-methyl-2-pyrrolidone with a bead mill in advance in a polyimide varnish (U-varnish A; Ube Industries, Ltd.) containing a polyimide resin precursor as a main component. The dispersion was prepared so that the carbon black content was 17% by weight of the polyamic acid solid content, and the mixture was thoroughly stirred to prepare a coating solution.

<Manufacture of intermediate transfer belt>
A metal cylindrical support having an outer diameter of 340 [mm] and a length of 360 [mm] roughened by blasting was used as a mold and attached to a roll coater. Next, the substrate coating liquid A is poured into the pan, the paint is pumped up at a rotation speed of 40 [mm / sec] of the coating roller, and the gap between the regulating roller and the coating roller is set to 0.6 [mm]. The top paint thickness was controlled. Then, the rotational speed of the cylindrical support is controlled to 35 [mm / sec] and close to the application roller, and the coating on the application roller is uniformly applied on the cylindrical support with a gap of 0.4 [mm] from the application roller. After the transfer coating, the hot air circulating dryer is charged while maintaining the rotation, the temperature is gradually raised to 110 [° C.] and heated for 30 minutes, further heated to 200 [° C.] for 30 minutes, Stopped spinning. Thereafter, this was introduced into a heating furnace (firing furnace) capable of high-temperature treatment, and the temperature was raised stepwise to 320 [° C.], followed by heat treatment (firing) for 60 minutes.

<Applying an elastic body to the substrate>
The respective constituent materials shown below were mixed and sufficiently kneaded using a biaxial kneader to prepare a rubber composition.

<Elastic body constituent material>
・ Acrylic rubber Nipol AR12 (Nippon ZEON Co., Ltd.) 100 parts by weight ・ Stearic acid Beads stearic acid Tsubaki (NOF Corporation) 1 part by weight ・ Red phosphorus Nova Excel 140F (Rin Chemical Industry Co., Ltd.) 10 parts by weight ・ Aluminum hydroxide Heidilite H42M (Showa Denko Co., Ltd.) 60 parts by weight / crosslinking agent Diak. No1 (hexamethylenediamine carbamate)
(DuPont Dow Elastomer Japan) 0.6 parts by weight / crosslinking accelerator VULCOFAC ACT55
(Salt of 70 [%] 1,8-diazabicyclo (5,4,0) undecene-7 and dibasic acid, 30 [%] amorphous silica) (Safic alca) 1 part by weight / conductive agent QAP-01 ( Tetrabutylammonium perchlorate)
(Nippon Carlit Co., Ltd.) 0.3 parts by weight

  Subsequently, the rubber composition thus obtained was dissolved in an organic solvent (MIBK: methyl isobutyl ketone) to prepare a rubber solution having a solid content of 35 [wt%]. The prepared rubber solution was moved to the support shaft method while continuously discharging the rubber paint from the nozzle onto the polyimide substrate while rotating the cylindrical support on which the polyimide substrate previously prepared was formed. Coated in a spiral. The coating amount was such that the final rubber film thickness was 500 [μm]. When the predetermined amount was completely poured and the coating film was evenly spread, spherical resin particles 31-3 were applied using the particle coating apparatus shown in FIG.

  Silicone resin particles (Tospearl 130 (volume average particle size: 3.0 [μm] product); Momentive Performance Materials) were used as the spherical resin particles 31-3.

  After finishing the particle application, the cylindrical support coated with the rubber paint is put into a hot air circulating dryer while rotating as it is, and the temperature is raised to 90 [° C.] at a heating rate of 4 [° C./min]. For 30 minutes. Subsequently, the temperature was raised to 170 [° C.] at a heating rate of 4 [° C./min], and heat treatment was performed for 60 minutes. After stopping the heating, it was gradually cooled to room temperature. After sufficiently cooling, it was removed from the mold to obtain an intermediate transfer belt.

〔toner〕
As described in detail below, a base material formed by particles (colored particles) granulated by desolvation after emulsifying or dispersing a stock solution (oil phase) of toner material in an aqueous medium (aqueous phase). 1 [parts by weight] of a chromium-containing metal complex dye was immobilized on the surface of the particles as a charge control agent.

[Production of toner]
(Synthesis of fine particle dispersion)
That is, 700 parts of water, 12 parts of sodium salt Eleminol RS-30 (manufactured by Sanyo Kasei Kogyo Co., Ltd.), 85 parts of styrene, 85 parts of methacrylic acid, 85 parts of water in a reaction vessel equipped with a stirring bar and a thermometer. Parts, 110 parts of butyl acrylate, and 1 part of ammonium persulfate were added and stirred at 400 rpm for 15 minutes to obtain a white emulsion. The system was heated to raise the system temperature to 75 ° C. and reacted for 5 hours.
Further, 30 parts of a 1% ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 5 hours, and an aqueous vinyl resin (a copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt). A dispersion [fine particle dispersion] was obtained.
The weight average particle diameter of the [fine particle dispersion] measured with LA-920 was 105 nm.
A portion of [the fine particle dispersion] was dried to isolate the resin component. The Tg of the resin was 60 ° C., and the weight average molecular weight was 160,000.

(Adjustment of aqueous phase)
990 parts of water, 83 parts of the above fine particle dispersion, 37 parts of a 48.5% aqueous solution of sodium dodecyl diphenyl ether disulfonate Eleminol MON-7 (manufactured by Sanyo Chemical Industries), and 90 parts of ethyl acetate were mixed and stirred to give a milky white liquid. Got. This is designated as [Aqueous Phase 1].

(Synthesis of low molecular weight polyester)
229 parts of bisphenol A ethylene oxide 2-mole adduct, 529 parts of bisphenol A propylene oxide 3-mole adduct, 208 parts of terephthalic acid, 46 parts of adipic acid and dibutyltin in a reaction vessel equipped with a condenser, stirrer and nitrogen inlet tube Add 2 parts of oxide, react at normal pressure and 230 ° C for 8 hours, and further react for 5 hours at 10-15 mmHg reduced pressure. Then, put 44 parts of trimellitic anhydride into the reaction vessel and add 180 parts at 180 ° C and normal pressure. The reaction was performed for a while to obtain [Low molecular weight polyester 1].
[Low molecular polyester 1] had a number average molecular weight of 2500, a weight average molecular weight of 6700, a Tg of 43 ° C., and an acid value of 25 mgKOH / g.

(Synthesis of intermediate polyester and prepolymer)
In a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe, 682 parts of bisphenol A ethylene oxide 2-mole adduct, 81 parts of bisphenol A propylene oxide 2-mole adduct, 283 parts of terephthalic acid, trimellitic anhydride 22 And 2 parts of dibutyltin oxide were added, reacted at normal pressure and 230 ° C. for 8 hours, and further reacted at reduced pressure of 10 to 15 mmHg for 5 hours to obtain [Intermediate Polyester 1].
[Intermediate Polyester 1] had a number average molecular weight of 2,100, a weight average molecular weight of 9,500, Tg of 55 ° C., an acid value of 0.5 mgKOH / g, and a hydroxyl value of 51 mgKOH / g.

Next, 410 parts of [the intermediate polyester 1], 89 parts of isophorone diisocyanate, and 500 parts of ethyl acetate are placed in a reaction vessel equipped with a cooling pipe, a stirrer, and a nitrogen introduction pipe, and reacted at 100 ° C. for 5 hours. [Prepolymer 1] was obtained.
[Prepolymer 1] had a free isocyanate weight% of 1.53%.

(Synthesis of ketimine)
In a reaction vessel equipped with a stirrer and a thermometer, 170 parts of isophoronediamine and 75 parts of methyl ethyl ketone were charged and reacted at 50 ° C. for 5 hours to obtain [ketimine compound]. The amine value of [the ketimine compound] was 418 mgKOH / g.

(Synthesis of master batch)
35 parts of water, 40 parts of phthalocyanine pigment FG7351 (manufactured by Toyo Ink Co., Ltd.) and 60 parts of polyester resin RS801 (manufactured by Sanyo Kasei Co., Ltd.) are mixed with a Henschel mixer (manufactured by Mitsui Mining Co., Ltd.), and the mixture is 150 using two rolls. After kneading at 30 ° C. for 30 minutes, the mixture was cooled by rolling and pulverized with a pulverizer to obtain a [master batch].

(Create oil phase)
In a container in which a stir bar and a thermometer are set, 378 parts of [low molecular weight polyester 1], 110 parts of carnauba wax, 22 parts of CCA (salicylic acid metal complex) E-84 (manufactured by Orient Chemical Co., Ltd.), 947 parts of ethyl acetate. The mixture was charged, heated to 80 ° C. with stirring, kept at 80 ° C. for 5 hours, and then cooled to 30 ° C. in 1 hour. Next, 500 parts of [Masterbatch] and 500 parts of ethyl acetate were charged in a container and mixed for 1 hour to obtain [Raw material solution].

[The above raw material solution] 1324 parts were transferred to a container, and using a bead mill, Ultra Visco Mill (manufactured by Imex), zirconia beads having a liquid feeding speed of 1 kg / hour, a disk peripheral speed of 6 m / second, and a particle diameter of 0.5 mm. The carbon black and the wax were dispersed under the condition of 3 passes. Next, 1324 parts of a 65% ethyl acetate solution of [the low molecular weight polyester] was added, and one pass was performed with a bead mill under the above conditions to obtain a [pigment / wax dispersion].
The solid content concentration of the [pigment / wax dispersion] (measurement conditions: 130 ° C., 30 minutes) was 50%.

(Emulsification)
[Pigment / Wax Dispersion] 648 parts, [Prepolymer] 154 parts, [Ketimine Compound] 6.6 parts are put in a container and mixed with TK homomixer (manufactured by Tokushu Kika Co., Ltd.) at 5000 rpm for 1 minute. After that, 1200 parts of [the aqueous phase 1] was added to the container, and mixed for 20 minutes at 13000 rpm with a TK homomixer to obtain [emulsified slurry].

  3. Selogen BS-H (Daiichi Kogyo Seiyaku Co., Ltd.) 3.15 parts was added little by little to 75.6 parts of ion-exchanged water being stirred at 2,000 rpm with a TK homomixer (made by Tokushu Kika). To do. Stir for 30 minutes while maintaining the addition at 20 ° C. 43.3 parts of 48.5% aqueous solution of sodium dodecyl diphenyl ether disulfonate (Eleminol MON-7: manufactured by Sanyo Chemical Industries) is added to the obtained serogen solution, and the mixture is added and stirred for 5 minutes while maintaining at 20 ° C. Into this, 2000 parts of [the emulsified slurry] was added and mixed with a TK homomixer at 2,000 rpm for 1 hour to obtain [shape control slurry].

(Solvent removal)
[Shape control slurry] was put into a container equipped with a stirrer and a thermometer, and after removing the solvent at 30 ° C. for 8 hours, aging was carried out at 45 ° C. for 4 hours to obtain [dispersed slurry].

(Washing, drying)
[100% of the dispersion slurry] was filtered under reduced pressure,
(1) 100 parts of ion-exchanged water was added to the filter cake, mixed with a TK homomixer (12000 rpm for 10 minutes), and then filtered.
(2) 100 parts of a 10% sodium hydroxide aqueous solution was added to the filter cake of (1), mixed with a TK homomixer (30 minutes at 12000 rpm), and then filtered under reduced pressure.
(3) 100 parts of 10% hydrochloric acid was added to the filter cake of (2), mixed with a TK homomixer (12000 rpm for 10 minutes), and then filtered.
(4) After adding 300 parts of ion-exchanged water to the filter cake of (3) and mixing with a TK homomixer (12000 rpm for 10 minutes), the filtration operation was performed twice to obtain [washed filter cake].

Using a circulating dryer, the [washing filter cake] is dried at 45 ° C. for 48 hours, and has an opening of 7
Sieve with a 5 μm mesh to obtain [toner base particles]. [Mother toner particles] had a volume average particle diameter (Dw) of 6.0 μm.

Next, 1 [parts by weight] large particle size silica, 3 [parts by weight] silica, and 2 [parts by weight] titanium oxide as external additives are mixed with the toner particles by a Henschel mixer. Toner was obtained.
The particle size of the large particle size silica is 60 [nm], the coverage of the large particle size silica is 7 [%], (large particle size silica + small particle size silica) / titanium oxide (= (large Si + small Si) / Ti ) Ratio was 2.

  As a condition for evaluating the blur, the system linear velocity was 2000 mm / sec.

[Example 2]
The conditions for evaluating the blur were the same as in Example 1 except that the system linear velocity was changed from 2000 mm / sec to 400 mm / sec.

[Comparative Example 1]
The conditions for evaluating the blur were the same as in Example 2 except that a fixing unit in which the carbon black content 17 [wt%] was changed to 10 [wt%] was used.

Example 3
The same procedure as in Example 2 was performed except that carbon black: 17 [wt%] used in Example 2 was changed to metal oxide: 20 [wt%].

[Comparative Example 2]
The same procedure as in Example 2 was performed except that the rubber film thickness used in Example 2 was changed to 100 [μm].

[Comparative Example 3]
The same procedure as in Example 2 was performed except that the particle size of the silicone resin particles used in Example 2 was changed to 10 [μm].

Example 4
The same procedure as in Example 2 was performed except that the silicone resin particles used in Example 2 were changed to acrylic resins.

Example 5
The large particle size silica used in Example 2 was changed from 1 [part by weight] to 4 [parts by weight], and the coverage of large particle size silica: 7 [%] was changed to 30 [%] (large particle size silica + Ratio of small particle size silica) / titanium oxide: The same procedure as in Example 2 was performed except that 2 was set to 3.5.

[Comparative Example 4]
Large particle size silica used in Example 2: 1 [parts by weight] was changed to 0.5 [parts by weight], large particle size silica coverage: 7 [%] was 3.5 [%], small particles Diameter silica: 3 [parts by weight] was changed to 1 [parts by weight] and the ratio of (large particle size silica + small particle size silica) / titanium oxide: 2 was changed to 0.75. It implemented like.

Example 6
The same procedure as in Example 2 was performed, except that the particle size of the large particle size silica used in Example 2 was changed from 60 [nm] to 200 [nm].

[Comparative Example 5]
The chromium-containing metal complex dye used in Example 2 was carried out in the same manner as in Example 2, except that 1 [part by weight] was changed to 0.05 [parts by weight].

A print test was performed using each developer. As a printer used for the print test, RICOH Pro c901 manufactured by Ricoh Co., Ltd. was modified to the configuration of the present invention and evaluated.
Measurement of system speed A4 paper, vertical direction paper (length of paper passing direction: 297 mm), continuous 100 sheets, output by an image forming apparatus described later, the output time from start to end is A second, and the system speed is In the case of B, the system speed was obtained by the following formula.
B (mm / sec) = 100 sheets × 297 mm ÷ A seconds In the print test, test images with a printing rate of 6% were continuously output on 50,000 sheets of A3 size paper. Thereafter, halftone images were output as sample images to three A3 size papers, and the blur in each was visually evaluated. The evaluation was performed by a sensory evaluation method in which a halftone image for a rank sample prepared in advance and a sample image were compared visually. [Visual evaluation of blurs]
: Rank 5
○: Rank 4
Δ: Rank 3
×: Rank 2
×: Rank 1

The higher the rank is, the more properly the toner is on the paper, and the lower the rank is, the more the toner is not transferred, and the white level is higher than rank 4 = ◯.
In addition, it is possible to replace it with a measured value that is a kind of graininess to some extent, but because it cannot be expressed with this measured value, a limit sample was used.

The results of this experiment are shown in Table 1.

(Reference in FIG. 1)
31 Intermediate transfer belt (intermediate transfer member)

(Reference in FIG. 2)
31-1 Base material 31-2 Elastic body 31-3 Resin particles

(Reference in FIG. 3)
61 Mold Drum 62 Belt 63 Applying Base Material and Elastic Body Pressing Member 64 Resin Particle 65 Powder Coating Device

(Reference in FIG. 4)
A Paint pan B Paint C Coating roll D Regulating roll E Cylindrical support (mold)

(Reference in FIG. 5)
71 Recording material 72 Toner

JP 2001-42666 A JP 2002-268285 A JP 2006-308979 A JP 2007-4081 A JP 2008-209848 A JP 2008-268435 A

Claims (7)

In an image forming apparatus having an endless intermediate transfer belt that conveys a sheet-like medium carrying a toner image and having a system speed of 400 to 2000 mm / sec.
The intermediate transfer belt has a laminated structure in which at least a first layer made of a base material and a second layer made of an elastic body in which spherical resin particles are arranged in the surface direction on the surface to form an uneven shape are sequentially laminated. The intermediate transfer belt contains an electric resistance adjusting material, and the intermediate transfer belt has a surface resistance of 1 × 10 ⁸ [Ω / □] to 1 × 10 ¹³ [Ω / □] and a volume resistance of It is adjusted to be in the range of 1 × 10 ⁶ [Ω · cm] to 1 × 10 ¹² [Ω · cm], and the second layer made of the elastic body is in the range of 200 [μm] to 2000 [μm]. The volume average particle diameter of the spherical resin particles used in the second layer is 0.5 [μm] to 5.0 [μm],
The toner is composed of base particles formed by colored particles granulated by desolvation after emulsifying or dispersing an oil phase of a stock solution containing a toner material in a solvent in an aqueous medium,
The base particles contain 0.2 [parts by weight] to 1 [parts by weight] charge control agent with respect to at least 100 [parts by weight] of the toner,
Are those obtained by attaching the three external additive on the surface of the base particles,
The external additive is a large particle size silica having a particle size of 25 [nm] to 270 [nm], a small particle size silica, and titanium oxide, and the large particle size silica is added to 100 [parts by weight] of the toner. And at least 1 [parts by weight], and the total use ratio thereof is 0.1 [parts by weight] to 12 [parts by weight] with respect to 100 [parts by weight] of the toner. An image forming apparatus characterized in that the ratio of diameter silica + small particle diameter silica) / titanium oxide is 1-10 .   2. The image according to claim 1, wherein the base material of the intermediate transfer belt is a resin material containing at least a polyimide or polyamideimide component or a fluorine resin component and an electrical resistance adjusting material. Forming equipment. The base material in the intermediate transfer belt of the intermediate transfer belt contains an electric resistance adjusting material, and the surface resistance of the second layer is 1 × 10 ⁸ [Ω / □] to 1 × 10 ¹³ [Ω / The volume resistance of the intermediate transfer belt is adjusted to be in the range of 1 × 10 ⁶ [Ω · cm] to 1 × 10 ¹² [Ω · cm]. The image forming apparatus described.   The electric resistance adjusting material of the base material of the intermediate transfer belt is selected from the group consisting of carbon black, metal or metal (sub) oxide, and organic ionic onium salt, and the content is the total solid content The image forming apparatus according to any one of claims 1 to 3, wherein the image forming apparatus is 0.5 [wt%] to 30 [wt%]. The elastic body of the intermediate transfer belt has a compressive Young's modulus of 0.5 to 80.0 MPa / m ² when any stress is applied in a stress range of ^{3 to} 50 N / mm ^2. The image forming apparatus according to claim 1.   The image forming apparatus according to claim 1, wherein the elastic body of the second layer in the intermediate transfer belt includes at least a partially curable resin material. The image forming apparatus according to any one of claims 1 to 6, wherein the coverage of the base particles of the large-diameter silica is 5 [%] to 45 [%].