JP4393952B2 - Toner production method - Google Patents

Description

  The present invention relates to a toner for developing an electrostatic latent image used for image formation by an electrostatic copying process such as a copying machine, a facsimile machine, and a printer, and also relates to an image forming apparatus using the toner.

2. Description of the Related Art Image forming apparatuses such as copying machines, printers, and facsimiles use an image forming method in which an electrostatic latent image by an electrophotographic method is visualized with toner of colored resin particles including a pigment. This image method can form images with high accuracy at high speed. In particular, it is not only a monochrome image but also a full-color image, and has durability and stability that can withstand long-term use. have.
However, recently, the required image quality has been increased, and what has been considered to be a sufficient level in the past is now required to be further improved. In particular, high reproducibility for fine lines and fine dots is demanded for image quality, and one technique corresponding to this is to use fine toner with a small particle diameter, and further use spherical toner. That is.
However, it is difficult to impart a sufficient charge amount to the toner having a reduced particle size. The reason for this is that, since the particles are small, the surface area thereof is large and the van der Waals force is also large, and the fluidity is lowered, so that it does not sufficiently rub against the frictional charge imparting member. For this reason, when toner having a small particle diameter is used, problems such as toner scattering and fogging often occur. Furthermore, since the adhesive force with the photosensitive member becomes strong, there is a problem that sufficient cleaning becomes difficult by a cleaning method using an elastomer blade having a simple structure at a low cost.
In addition, since the spherical toner flies and moves faithfully to the electric field, a high-definition latent image can be developed with high reproducibility. Furthermore, the same and high-efficiency transfer can be performed for the electric field in transfer. However, since it is easy to roll on the photoreceptor, there is a problem that sufficient cleaning becomes difficult by a cleaning method using a blade.

In order to improve these problems, an external additive is used for the toner to control the adhesion force to improve fluidity and adjust the charge amount.
For example, “electrostatic image developer” in Patent Document 1 discloses a toner containing “silica fine particles obtained by a substantially spherical deflagration method”. Further, in “Full Color Toner” of Patent Document 2, “full color toner used for an intermediate transfer type electrophotographic apparatus in which a toner image of each color is sequentially transferred to an intermediate transfer body and then transferred to a transfer material to form an image. In the toner, a toner is disclosed in which inorganic fine particles having an average particle size of 20 to 350 nm are externally added to the surface of resin fine particles containing a binder resin and a colorant. In the “static toner image developing toner composition” of Patent Document 3, “average particle diameter of 30 nm or more treated with a fluorine-containing coupling agent of 5 to 90 parts by weight with respect to 100 parts by weight of toner particles and fine particles to be treated” is disclosed. Toners containing 500 nm surface-treated microparticles are disclosed. The “electrostatic latent image developing toner” of Patent Document 4 includes “hydrophobic inorganic fine particles A having a number average particle diameter of 5 to 70 nm and particles having a number average particle diameter of 80 to 800 nm and a predetermined particle diameter. A toner containing “inorganic fine particles B” is disclosed. In “Electrophotographic developer” of Patent Document 5, “inorganic compound A having an average particle size of 8 to 20 nm as an external additive and toner particles having a volume average particle size D50 of 3 to 9 μm and an average particle size of A toner is disclosed in which an inorganic compound B of 30 to 70 nm and an inorganic oxide C having an average particle size of 300 to 600 nm are added. The “image forming apparatus” of Patent Document 6 discloses a toner “containing inorganic fine particles treated with silicone oil as an external additive”.

  In “Color Electrophotographic Toner” of Patent Document 7, “the external additive is at least three kinds of first hydrophobic silica fine particles, second hydrophobic silica fine particles, and hydrophobic titanium oxide fine particles, A "satisfying relationship" toner is disclosed. The “toner composition” of Patent Document 8 discloses a toner comprising “a surface additive mixture comprising two kinds of coated silica and a coated metal oxide”. In “Toner” of Patent Document 9, a toner containing “monodispersed spherical silica whose external additive has a true specific gravity of 1.3 to 1.9 and a volume average particle diameter of 80 to 300 nm” is disclosed. Has been. In the “toner” of Patent Document 10, “in a negatively charged toner obtained by mixing and adding at least three kinds of external additives, the external additive includes first inorganic fine particles having a number average particle diameter of 10 to 30 nm, There is disclosed a toner comprising a second inorganic fine particle having an average particle diameter of 10 to 90 nm and a third inorganic fine particle having a number average particle diameter of 100 to 1000 nm and having a predetermined relationship. In “Toner” of Patent Document 11, “a number average primary particle size of 5 nm or more and less than 15 nm, a small particle size fine particle A, a number average primary particle size of 15 nm or more and less than 80 nm, and a number average primary particle A toner comprising large particle C having a diameter of 80 nm or more and 500 nm or less.

JP-A-5-224456 JP 2001-340007 A JP 9-319135 A JP-A-10-207112 JP-A-11-143115 JP 200-267343 A JP 2000-321812 A JP 2001-22119 A JP 2001-66820 A Japanese Patent Laid-Open No. 10-10773 JP 2001-147547 A

  However, any of the disclosed techniques adds a plurality of external additives to the toner surface. These external additives can be mixed by, for example, (1) a simultaneous addition method in which external additives having a small particle size, medium particle size, and large particle size are added together into a toner base and mixed, and (2) a large particle size Large particle size pre-addition system in which external additives are added and mixed in advance, then small particle size / medium particle size external additives are added and mixed, (3) small particle size / medium particle size After adding the external additives in advance, the large particle size post-addition method is used in which the large particle size external additive is added and further mixed. Since the external additives have different behaviors such as embedding during mixing, their functions cannot be fully exhibited.

Therefore, the present invention has been made in view of the above problems, and the problem is that there is no liberation of the external additive from the toner surface, and the external additive is well fixed and does not cause burial. To provide a toner and a developer capable of obtaining stable chargeability and fluidity.
Another object of the present invention is to provide a developing device, a process cartridge, and an image forming apparatus capable of obtaining a high-quality image over a long period of time by using a toner capable of obtaining stable chargeability and fluidity.

The features of the present invention, which is a means for solving the above problems, are listed below.
1. Method for producing a toner of the present invention is a method for producing a toner containing at least two types of toner particles external additive is added to the surface of the mother toner particles comprising at least a binder resin and a colorant, wherein the base particles as one type of using base particles before Symbol toner base particles, at least two of each external additive was added to and mixed alone, create at least two types of toner particles, at least two types that the created It is characterized by mixing toner particles .
2. The toner production method of the present invention is further characterized in that the at least two types of external additives have different number average particle diameters.
3. In the toner production method of the present invention, the at least two kinds of external additives further include at least an external additive having a number average particle diameter in the range of 75 to 500 nm and a number average particle diameter of 5 to 20 nm. you wherein there between the external additive in the range.

4). In the toner production method of the present invention, the at least two types of external additives further include at least an external additive having a number average particle diameter in the range of 75 to 500 nm and a number average particle diameter of 20 to 75 nm. An external additive in the range and an external additive having a number average particle diameter in the range of 5 to 20 nm.
5. The toner manufacturing method of the present invention is further characterized in that the at least two types of external additives are different in material.
6). The toner production method of the present invention is further characterized in that the plurality of external additives are inorganic fine particles and / or organic fine particles.
7). In the toner production method of the present invention, the at least two types of external additives are characterized in that the inorganic fine particles are silica, titania, and alumina.

According to the present invention, in the toner and developer of the present invention, the external additive is less likely to be buried in the toner surface, and stable fluidity and charge amount can be obtained over a long period of time.
In addition, the developing device, process cartridge, and image forming apparatus of the present invention can be cleaned even with spherical and small-diameter toner, and a high-quality image with little background stains can be obtained.

  The best mode for carrying out the present invention will be described below with reference to the drawings. Note that it is easy for a person skilled in the art to make other embodiments by changing or correcting the present invention within the scope of the claims, and these changes and modifications are included in the scope of the claims. The following description is an example of the best mode of the present invention, and does not limit the scope of the claims.

The toner of the present invention is a toner for developing an electrostatic latent image, and includes a toner composed of at least a binder resin and a colorant, and an external additive added to the surface of the toner particle. Each of these external additives is externally added alone, and toner particles to which the single external additive is externally added are mixed.
The toner particles used in the toner of the present invention include production methods such as a pulverization method and a polymerization method (suspension polymerization, emulsion polymerization, dispersion polymerization, emulsion aggregation, emulsion association, etc.), but are not limited to these production methods. . As an example of the pulverization method, first, a binder resin, a pigment or dye as a colorant, a charge control agent, a release agent, other additives, etc. are sufficiently mixed by a mixer such as a Henschel mixer, and then batch type. The constituent materials are well kneaded using a two-roll, Banbury mixer, continuous twin-screw extruder, continuous single-screw kneader, or the like, and cut after rolling and cooling. The toner kneaded product after cutting is crushed, coarsely pulverized using a hammer mill, etc., and further pulverized by a fine pulverizer or mechanical pulverizer using a jet stream, and a classifier or Coanda effect using a swirling airflow Is classified to a predetermined particle size by a classifier using As an example of the polymerization method, a toner composition containing at least a polymer having an active hydrogen group, polyester, a colorant, and a release agent is crosslinked and / or extended in an aqueous medium in the presence of resin fine particles. It is preferable to use toner.

As the external additive, inorganic fine particles and organic fine particles can be used. As the inorganic fine particles, metal compounds such as oxides, nitrides, carbides, and carbonates are used. Specific examples of the inorganic fine particles include, for example, silicon oxide (silica), aluminum oxide (alumina), titanium oxide (titania), zinc oxide, zirconium oxide, cerium oxide, tungsten oxide, manganese oxide, and barium titanate and titanium. Examples thereof include oxides such as strontium acid, magnesium titanate, calcium carbonate, and potassium carbonate, silicon nitride, aluminum nitride, and the like, nitrides such as carbon nitride, and carbides such as nitrogen carbide. In particular, oxides of silicon, titanium, and aluminum are preferably used.
In addition, the organic fine particles include polymer fine particles such as vinyl resins, polyurethane resins, epoxy resins, polyester resins, polyamide resins, polyimide resins, silicon resins obtained by soap-free emulsion polymerization, suspension polymerization, and dispersion polymerization. Examples thereof include polymer particles made of resin, phenol resin, melamine resin, urea resin, aniline resin, ionomer resin, and polycarbonate resin.

Such an external additive can be surface-treated to increase hydrophobicity and prevent deterioration of flow characteristics and charging characteristics even under high humidity. For example, silane coupling agents, silylating agents, silane coupling agents having an alkyl fluoride group, organic titanate coupling agents, aluminum coupling agents, silicone oils, modified silicone oils and the like are preferable surface treatment agents. It is done. The number average particle size of the primary particles before forming the aggregate of the external additive is preferably 5 nm to 500 nm. The use ratio of the inorganic fine particles is preferably 0.01 to 5% by weight of the toner, and particularly preferably 0.01 to 4.0% by weight.
Examples of the cleaning property improver for removing the developer after transfer remaining on the photosensitive member or the primary transfer medium include fatty acid metal salts such as zinc stearate and calcium stearate, such as polymethyl methacrylate fine particles and polystyrene fine particles. Examples thereof include fine polymer particles produced by soap-free emulsion polymerization. The polymer fine particles preferably have a relatively narrow particle size distribution and a number average particle size of 1 nm to 100 nm.

The toner of the present invention uses a plurality of external additives having different number average particle diameters. Conventionally, external addition of a plurality of external additives having different number average particle diameters is performed as follows. It was. For example, (1) a simultaneous addition method in which an external additive having a small particle size, a medium particle size, and a large particle size is added to the toner base and mixed together, and (2) an external additive having a large particle size is added in advance. After mixing, a small particle size / medium particle size external additive is added and further mixed, (3) small particle size / medium particle size external additive is mixed in advance After that, a large particle size post-addition system is used in which an external additive having a large particle size is added and further mixed.
In the (1) simultaneous addition method and (3) the large particle size post-addition method, the large particle size external additive is not easily fixed to the toner particles, and the large particle size external additive is easily released by stirring in the developing section. In addition, (2) in the large particle size pre-addition method, the large particle size external additive is relatively easily fixed, but the small or medium particle size external additive is fixed on the surface of the large particle size external additive. May impair liquidity. Furthermore, if strong agitation is performed to firmly fix the large particle size external additive, the small or medium particle size external additive can be present on the toner surface instead of the large particle size external additive surface. However, at this time, the external additive having a small or medium particle diameter is buried in the toner particles and the fluidity is impaired.

Therefore, the present invention produces a toner to which a plurality of types of external additives are added and to which an external additive having a different number average particle size is added alone. The toner is mixed in accordance with the amount of the external additive added to form one toner.
For example, when three types of external additives having different number average particle diameters are added, (1) a toner obtained by mixing a small particle diameter external additive alone with respect to toner particles, and (2) a medium particle diameter First, a toner in which an external additive is mixed alone, and (3) a toner in which an external additive having a large particle diameter is mixed alone are prepared. These three kinds of toners are adjusted to toners having desired characteristics by changing the mixing ratio of the respective toners and using the toner mixed with the external additive. Compared to the conventional mixing means described above, this does not hinder the small or medium particle size external additive from being fixed to the toner particle surface due to the presence of the large particle size external additive. . Further, the presence of the external additive having a small or medium particle size does not hinder the large particle size external additive from being fixed to the toner particle surface. As a result, a small, medium and large particle size external additive is present on the surface of the toner particles, and the toner can effectively utilize the respective characteristics.

Here, the external additive having a different particle size has been described as an example, but the same applies to the case of mixing external additive materials such as silica, titania, and alumina. In addition, when the surface treatment agent is different and the charging property is different, or when the external additive has a different shape such as an indefinite shape, a spherical shape, an elliptical shape, etc., they are mixed individually as described above. This is because the mixing characteristics differ depending on the characteristics of the external additive, and in the same way as in the case where the particle diameters are different, the mixing may be carried out by uniformly mixing so as not to be unevenly distributed. External additives with poor mixing properties are ubiquitous when combined with the better one.
Accordingly, toner particles obtained by mixing each external additive alone are prepared according to the mixing characteristics depending on the material, chargeability, shape, particle size, etc. of the external additive, and these are further mixed to obtain a toner. .

  For the mixing of the external additive, a general powder mixer is used, but it is preferable to use a device equipped with a jacket or the like and capable of adjusting the internal temperature. Moreover, the rotation speed, rolling speed, time, temperature, etc. of the mixer are changed. For example, a strong load may be given first, and then a relatively weak load, or vice versa. Examples of mixing equipment that can be used include a V-type mixer, a rocking mixer, a Ladige mixer, a Nauter mixer, a Henschel mixer, and the like.

The toner of the present invention uses an external additive having a number average particle diameter in the range of 75 to 500 nm and an external additive having a number average particle diameter in the range of 5 to 20 nm. The external additive having a number average particle diameter in the range of 75 to 500 nm is on the toner surface and can increase the distance between the toner surface and the photoreceptor, thereby increasing the transfer rate and facilitating cleaning. Can be. Further, if it is present on the surface of the cleaning blade, it is present between the toner and the cleaning blade, and the effect of preventing the toner from slipping through the cleaning blade is great.
However, the adhesion force between the contacting objects is weakened. For this reason, since it is easily released from the toner surface and stays on the toner surface, the contribution to the fluidity and charge amount of the toner is small.

  Furthermore, it is preferable to externally add an external additive having a number average particle diameter in the range of 5 to 20 nm. An external additive in this range further improves the fluidity of the toner and can easily supply the toner when the toner is replenished. Further, the toner charge amount can be increased, and the toner charge amount adjustment can be facilitated. As described above, the external additive in the range of 5 to 20 nm allows the external additive to uniformly adhere to the toner surface, so that the chargeability of the toner is stabilized, and the burying speed due to the particle size difference of the external additive. Even if there is a difference, a toner having stable fluidity and chargeability over a long period of time can be obtained. Further, by using a toner having a large particle diameter of 75 to 500 nm that does not easily adhere to the toner surface and a small particle diameter of 5 to 20 nm that easily adheres to the toner surface, these toners can be used on the photoreceptor. By mixing these external additives, even if the toner has a low cleaning property, these external additives are accumulated at the tip of the cleaning blade and can be cleaned by damming.

In addition, the external additive having a number average particle size in the range of 20 to 75 nm has a strong adhesive force between the additive and the external additive. For this reason, it becomes difficult to separate from the toner surface, and it stays on the toner surface, thereby improving the fluidity of the toner. Furthermore, the increases in surface area because the particle element size is small, increases the charge amount per unit weight, greatly contributes to the adjustment of the charge amount of the toner.
Further, since it is not loose from the toner surface, it is less likely to float on and adhere to the photoconductor as an image carrier, and the filming margin of the toner can be improved. However, since the external additive having a small particle diameter stays on the toner surface, the distance between the toner surface and the photoconductor cannot be increased when it is on the photoconductor, and the electric attractive force between the toner and the photoconductor Cannot be reduced, and toner cleaning failure may occur. Further, even if the toner is slightly separated from the surface of the toner and is on the photosensitive member and adheres to the cleaning blade, the cleaning blade slips through with the toner, and the toner cleaning blade cannot be prevented from slipping through.
Therefore, by mixing and using toners to which both of these external additives are added, the fluidity of the external additives having a number average particle diameter in the range of 20 to 75 nm is improved, and the charge amount is adjusted. Furthermore, an external additive in the range of 75 to 500 nm can provide a toner that can increase the transfer rate and facilitate cleaning.

Silica preferably has a substantially spherical shape and is monodispersed. However, it is preferable to use agglomerated aggregates such as grape bunches after being pulverized and dispersed. Further, although it varies depending on the surface treatment agent, it is often negatively charged and is preferably used for controlling the negative charge amount of the toner. Further, since titania and alumina are often aggregates, they are similarly added after loosening to fine particles. Further, since negative chargeability is not strong like silica, it is preferably used for adjusting the negative charge amount of the toner.
Therefore, in a toner combining these external additives having different particle sizes, shapes, and charging properties, the toner obtained by adding the external additive alone is mixed so that the ratio of the external additive is constant. By mixing the toner, the fluidity, chargeability, and cleaning properties of the toner can be controlled.

In the image forming apparatus of the present invention, the average circularity is preferably 0.92 or more. Further, the average circularity is preferably 0.92 or more from the viewpoint of obtaining high image quality because of excellent dot reproducibility and good transferability. Further, since the average circularity is high, the toner is uniformly developed and transferred, and the toner is less likely to clump and adhere uniformly in the halftone portion and the solid portion, and is uniformly distributed. This makes it possible to reproduce a uniform intermediate color with little color unevenness when the toners are stacked and color overlapped, and the color reproduction range can be further expanded. When the average circularity is less than 0.92 and the toner has a shape separated from the spherical shape, it is difficult to obtain a high-quality image having sufficient transferability or dust. Such irregularly shaped particles have many points of contact with the smooth medium on the photoreceptor and the charge concentrates on the tip of the protrusion, so van der Waals force and mirror force are more than those with relatively spherical particles. Wearing power is high. For this reason, in the electrostatic transfer process, the spherical particles are selectively moved in the toner in which the amorphous particles and the spherical particles are mixed, and the character portion and the line portion image are lost. Further, the remaining toner has to be removed for the next development step, and there arises a problem that a cleaning device is necessary and the toner yield (the ratio of toner used for image formation) is low.
Further, the ratio of toner particles having a toner circularity of less than 0.91 is preferably 30% or less. A toner having a large variation in circularity such that the ratio exceeds 30% is not preferable because the charging speed and level are widened and the charge amount distribution is widened.
The circularity of the toner is a value obtained by optically detecting particles and dividing by the circumference of an equivalent circle having the same projected area. Specifically, the measurement is performed using a flow type particle image analyzer (FPIA-2000; manufactured by Sysmex Corporation). In a predetermined container, 100 to 150 mL of water from which impure solids are removed in advance is added, 0.1 to 0.5 mL of a surfactant is added as a dispersant, and about 0.1 to 9.5 g of a measurement sample is further added. The suspension in which the sample is dispersed is subjected to dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the concentration and dispersion of the dispersion are set to 3,000 to 10,000 / μL, and the shape and distribution of the toner are measured.

The image forming apparatus of the present invention has a weight average particle diameter of 3.0 to 8.0 μm and a ratio (D4 / Dn) of the weight average particle diameter (D4) to the number average particle diameter (Dn) of 1. It is preferable to use a toner in the range of 00 to 1.40. The weight average particle diameter is preferably 3.0 to 7.0 μm and D4 / Dn 1.00 to 1.25. By using such a toner, a full color image has a wide reproduction range of intermediate colors and absorption. A vivid color image with a narrow area can be obtained.
It is said that the smaller the toner particle diameter is, the more advantageous it is for obtaining a high-resolution and high-quality image, but it is disadvantageous for transferability and cleaning property. In addition, when the weight average particle diameter is smaller than this range, in the case of a two-component developer, the toner is fused to the surface of the magnetic carrier during long-term agitation in the developing device, and the charging ability of the magnetic carrier is reduced. When used as a system developer, toner filming on the developing roller and toner fusion to a member such as a blade for thinning the toner are likely to occur. In addition, these phenomena are greatly related to the content of fine powder. Particularly, when the particle diameter of the toner exceeds 3%, the adhesion to the magnetic carrier and the stability of charging at a high level are hindered. Become. On the contrary, when the weight average particle diameter of the toner is larger than this range, it is difficult to obtain a high-resolution and high-quality image. Further, in a color image, the reproducibility of intermediate colors is lowered, the graininess is increased, and the quality of the color image is lowered.
On the other hand, if D4 / Dn exceeds 1.40, the charge amount distribution becomes wide and the resolving power decreases, which is not preferable.
The average particle size and particle size distribution of the toner can be measured using a Coulter Counter TA-II and Coulter Multisizer II (both manufactured by Coulter). In the present invention, a Coulter Counter TA-II type was used and connected to an interface (manufactured by Nikka Giken) for outputting the number distribution and weight distribution and a PC 9801 personal computer (manufactured by NEC).

The image forming apparatus of the present invention uses toner having a shape factor SF-1 in the range of 100 to 180 and a shape factor SF-2 in the range of 100 to 180.
FIG. 1 is a diagram schematically showing the shape of the toner, and is a diagram for explaining the shape factor SF-1 and the shape factor SF-2.
The substantially spherical shape of the toner of the present invention is represented by a shape factor SF-1, and the value of SF-1 is preferably in the range of 100 to 180. Here, the shape factor SF-1 indicates the ratio of the roundness of the toner shape, and is represented by the following formula (1). This is a value obtained by dividing the square of the maximum length MXLNG of the shape formed by projecting toner on a two-dimensional plane by the figure area AREA and multiplying by 100π / 4.
SF-1 = {(MXLNG) ² / AREA} × (100π / 4) (1)
When the value of SF-1 is 100, the shape of the toner becomes a true sphere, and becomes larger as the value of SF-1 increases. When the value of SF-1 exceeds 180, the cleaning property is improved, but the spherical shape is greatly deviated, so that the charge amount distribution is widened, the ground cover is increased, and the image quality is lowered. Further, since the development and transfer by the electric field are not faithful to the lines of electric force due to the resistance of air in movement, the toner is developed between the fine lines, the image uniformity is lowered, and the image quality is lowered. In particular, in the reproduction of a color image, the color unevenness of the halftone part and the solid part increases, and the graininess increases and the quality of the color image decreases. Furthermore, 110-150 are more preferable, and 115-145 are more preferable.

In the toner of the present invention, the unevenness of the toner surface is represented by a shape factor SF-2, and the value of SF-2 is preferably in the range of 100 to 180. Here, the shape factor SF-2 indicates the ratio of unevenness in the shape of the toner, and is represented by the following formula (2). A value obtained by dividing the square of the perimeter PERI of the figure formed by projecting the toner onto the two-dimensional plane by the figure area AREA and multiplying by 100 / 4π.
SF-2 = {(PERI) ² / AREA} × (100 / 4π) (4)
When the value of SF-2 is 100, unevenness does not exist on the toner surface, and as the value of SF-2 increases, the unevenness of the toner surface becomes more prominent. When the value of SF-2 exceeds 1800, the cleaning property is improved, but the unevenness of the toner surface becomes large, the charge amount distribution is widened, the ground cover is increased, and the image quality is lowered. Further, in color image reproduction, the color unevenness of the halftone part and the solid part increases, and the graininess increases and the quality of the color image decreases. Even if the value of SF-2 is 100 and the surface is smooth, the above-described toner can be cleaned even by the blade cleaning method, and a high-quality image can be obtained because the charge amount distribution is narrow. Furthermore, 110-150 are more preferable, and 115-145 are more preferable.

As the polymerization toner, a toner that forms particles in an aqueous medium by dissolving or dispersing at least a binder resin and / or a binder resin precursor and a release agent in an organic solvent or a polymerizable monomer. Use. Hereinafter, the constituent material of the toner and a suitable manufacturing method will be described.
(polyester)
The polyester is obtained by a polycondensation reaction between a polyhydric alcohol compound and a polycarboxylic acid compound.
Examples of the polyhydric alcohol compound (PO) include dihydric alcohol (DIO) and trihydric or higher polyhydric alcohol (TO). (DIO) alone or a mixture of (DIO) and a small amount of (TO) preferable. Examples of the dihydric alcohol (DIO) 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, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.); alicyclic diols (1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.); bisphenols (bisphenol A, bisphenol) F, bisphenol S, etc.); alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adduct of the above alicyclic diol; Alkylene oxide bisphenol (ethylene oxide, propylene oxide, butylene oxide, etc.), etc. adducts. Among them, preferred are alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols, and particularly preferred are alkylene oxide adducts of bisphenols and alkylene glycols having 2 to 12 carbon atoms. It is a combined use. As trihydric or higher polyhydric alcohol (TO), 3 to 8 or higher polyhydric aliphatic alcohol (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); trihydric or higher phenols (Trisphenol PA, phenol novolak, cresol novolak, etc.); and alkylene oxide adducts of the above trivalent or higher polyphenols.

  Examples of the polyvalent carboxylic acid (PC) include divalent carboxylic acid (DIC) and trivalent or higher polyvalent carboxylic acid (TC). (DIC) alone and (DIC) with a small amount of (TC) Mixtures are preferred. Divalent carboxylic acids (DIC) 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) And naphthalenedicarboxylic acid). Of these, preferred are alkenylene dicarboxylic acids having 4 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 20 carbon atoms. Examples of the trivalent or higher polyvalent carboxylic acid (TC) include aromatic polycarboxylic acids having 9 to 20 carbon atoms (such as trimellitic acid and pyromellitic acid). In addition, as polyhydric carboxylic acid (PC), you may make it react with polyhydric alcohol (PO) using the above-mentioned acid anhydride or lower alkyl ester (Methyl ester, ethyl ester, isopropyl ester, etc.).

The ratio of the polyhydric alcohol (PO) to the polycarboxylic acid (PC) is usually 2/1 to 1/1, preferably as the equivalent ratio [OH] / [COOH] of the hydroxyl group [OH] and the carboxyl group [COOH]. Is 1.5 / 1 to 1/1, more preferably 1.3 / 1 to 1.02 / 1.
The polycondensation reaction between a polyhydric alcohol (PO) and a polycarboxylic acid (PC) is carried out in the presence of a known esterification catalyst such as tetrabutoxytitanate or dibutyltin oxide, and heated to 150 to 280 ° C. while reducing the pressure as necessary. The produced water is distilled off to obtain a polyester having a hydroxyl group. The hydroxyl value of the polyester is preferably 5 or more, and the acid value of the polyester is usually 1 to 30, preferably 5 to 20. By giving an acid value, it tends to be negatively charged, and furthermore, when fixing to a recording paper, the affinity between the recording paper and the toner is good and the low-temperature fixability is improved. However, when the acid value exceeds 30, there is a tendency to deteriorate with respect to the stability of charging, particularly environmental fluctuation.
The weight average molecular weight is 10,000 to 400,000, preferably 20,000 to 200,000. A weight average molecular weight of less than 10,000 is not preferable because offset resistance deteriorates. On the other hand, if it exceeds 400,000, the low-temperature fixability is deteriorated.

  In addition to the unmodified polyester obtained by the above polycondensation reaction, the polyester preferably contains a urea-modified polyester. The urea-modified polyester is obtained by reacting a terminal carboxyl group or hydroxyl group of the polyester obtained by the above polycondensation reaction with a polyvalent isocyanate compound (PIC) to obtain a polyester prepolymer (A) having an isocyanate group. It is obtained by cross-linking and / or extending the molecular chain by the reaction of the amine with amines.

Examples of the polyvalent isocyanate compound (PIC) 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.); aromatic aliphatic diisocyanates (α, α, α �, α � -tetramethylxylylene diisocyanate, etc.); isocyanates; Those blocked with a derivative, oxime, caprolactam, etc .; and combinations of two or more of these.
The ratio of the polyvalent isocyanate compound (PIC) is usually 5/1 to 1/1, preferably as an equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester having a hydroxyl group. 4/1 to 1.2 / 1, more preferably 2.5 / 1 to 1.5 / 1. When [NCO] / [OH] exceeds 5, low-temperature fixability deteriorates. When the molar ratio of [NCO] is less than 1, when a urea-modified polyester is used, the urea content in the ester is lowered and hot offset resistance is deteriorated.

The content of the polyvalent isocyanate compound (PIC) component in the polyester prepolymer (A) having an isocyanate group is usually 0.5 to 40 wt%, preferably 1 to 30 wt%, more preferably 2 to 20 wt%. . If it is less than 0.5 wt%, the hot offset resistance deteriorates, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability. On the other hand, if it exceeds 40 wt%, the low-temperature fixability deteriorates.
The number of isocyanate groups contained per molecule in the polyester prepolymer (A) having an isocyanate group is usually 1 or more, preferably 1.5 to 3 on average, more preferably 1.8 to 2 on average. Five. If it is less than 1 per molecule, the molecular weight of the urea-modified polyester will be low, and the hot offset resistance will deteriorate.

Next, as amines (B) to be reacted with the polyester prepolymer (A), a divalent amine compound (B1), a trivalent or higher polyvalent amine compound (B2), an amino alcohol (B3), an amino mercaptan (B4) ), Amino acid (B5), and amino acid block of B1 to B5 (B6).
Examples of the divalent amine compound (B1) include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4 � -diaminodiphenylmethane, etc.); alicyclic diamines (4,4 � -diamino-3,3 � -dimethyldicyclohexylmethane, diaminecyclohexane, isophoronediamine, etc.); and aliphatic diamines (ethylenediamine, tetramethylenediamine, hexamethylenediamine, etc.) and the like. Examples of the trivalent or higher polyvalent amine compound (B2) include diethylenetriamine and triethylenetetramine. 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. Examples of the compound (B6) obtained by blocking the amino group of B1 to B5 include ketimine compounds and oxazolidine compounds obtained from the amines of B1 to B5 and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.). Among these amines (B), preferred are B1 and a mixture of B1 and a small amount of B2.

The ratio of amines (B) is equivalent to the equivalent ratio [NCO] / [NHx] of isocyanate groups [NCO] in the polyester prepolymer (A) having isocyanate groups and amino groups [NHx] in amines (B). 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 more than 2 or less than 1/2, the molecular weight of the urea-modified polyester is lowered, and the hot offset resistance is deteriorated.
The urea-modified polyester may contain a urethane bond together with a urea bond. The molar ratio of the urea bond content to the urethane bond content is usually 100/0 to 10/90, preferably 80/20 to 20/80, and more preferably 60/40 to 30/70. When the molar ratio of the urea bond is less than 10%, the hot offset resistance is deteriorated.

  The urea-modified polyester is produced by a one-shot method or the like. Polyhydric alcohol (PO) and polyvalent carboxylic acid (PC) are heated to 150-280 ° C. in the presence of a known esterification catalyst such as tetrabutoxytitanate, dibutyltin oxide, etc., and water generated while reducing the pressure as necessary. Distill off to obtain a polyester having a hydroxyl group. Subsequently, at 40-140 degreeC, this is made to react with polyvalent isocyanate (PIC), and the polyester prepolymer (A) which has an isocyanate group is obtained. Further, this (A) is reacted with amines (B) at 0 to 140 ° C. to obtain a urea-modified polyester.

When reacting (PIC) and when reacting (A) and (B), a solvent may be used if necessary. Usable solvents include aromatic solvents (toluene, xylene, etc.); ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.); esters (ethyl acetate, etc.); amides (dimethylformamide, dimethylacetamide, etc.) and ethers And those inert to isocyanates (PIC), such as tetrahydrofuran (such as tetrahydrofuran).
In addition, in the crosslinking and / or extension reaction between the polyester prepolymer (A) and the amines (B), a reaction terminator may be used as necessary to adjust the molecular weight of the resulting urea-modified polyester. Examples of the reaction terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.), and those obtained by blocking them (ketimine compounds).
The weight average molecular weight of the urea-modified polyester is usually 10,000 or more, preferably 20,000 to 10,000,000, and more preferably 30,000 to 1,000,000. If it is less than 10,000, the hot offset resistance deteriorates. The number average molecular weight of the urea-modified polyester or the like is not particularly limited when the above-mentioned unmodified polyester is used, and may be a number average molecular weight that can be easily obtained to obtain the weight average molecular weight. When the urea-modified polyester is used alone, its number average molecular weight is usually 2000-15000, preferably 2000-10000, more preferably 2000-8000. When it exceeds 20000, the low-temperature fixability and the glossiness when used in a full-color apparatus are deteriorated.

By using the unmodified polyester and the urea-modified polyester in combination, the low-temperature fixability and the gloss when used in the full-color image forming apparatus 100 are improved. Therefore, it is preferable to use the urea-modified polyester alone. In addition, polyester modified by chemical bonds other than urea bonds may be included.
The unmodified polyester and the urea-modified polyester are preferably at least partially compatible with each other in terms of low-temperature fixability and hot offset resistance. Therefore, it is preferable that the unmodified polyester and the urea-modified polyester have a similar composition.
The weight ratio of unmodified polyester to urea-modified polyester is usually 20/80 to 95/5, preferably 70/30 to 95/5, more preferably 75/25 to 95/5, and particularly preferably 80 /. 20-93 / 7. When the weight ratio of the urea-modified polyester is less than 5%, the hot offset resistance is deteriorated, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability.

The glass transition point (Tg) of the binder resin containing unmodified polyester and urea-modified polyester is usually 45 to 65 ° C, preferably 45 to 60 ° C. If it is less than 45 ° C., the heat resistance of the toner deteriorates, and if it exceeds 65 ° C., the low-temperature fixability becomes insufficient.
In addition, since the urea-modified polyester is likely to be present on the surface of the obtained toner base particles, the heat-resistant storage stability tends to be good even when the glass transition point is low as compared with known polyester-based toners.

(Coloring agent)
As the colorant, all known dyes and pigments can be 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, Bengala, Red Dan, Lead Zhu, Cadmium Red, Cadmium Mercury Red, Antimon Zhu, Permanent Red 4R, Para Red, Phi Sayred, Parachlor Ortonito Aniline Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine B, 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, Tolujing 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, Thio Indigo Red B, Thioindigo Maroon, Oil Red, Quinacridone Red, Pyrazolone Red Polyazo Red, Chrome Vermillion, Benzidine Orange, 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 blue, bitumen, anthraquinone blue, fast violet B, methyl violet lake, cobalt purple, manganese purple, dioxane violet, anthraquinone violet, chrome green, zinc green, chromium oxide, pyridian, emerald green, pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Lake, Lid Russian nin green, anthraquinone green, titanium oxide, zinc white, litbon and mixtures thereof can be used. The content of the colorant is usually 1 to 15% by weight, preferably 3 to 10% by weight, based on the toner.

  The colorant can also be used as a master batch combined with a resin. As a binder resin to be kneaded with the production of the master batch or the master batch, a polymer of styrene such as polystyrene, poly-p-chlorostyrene, polyvinyl toluene or the like, or a copolymer of these and a vinyl compound, Polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, fat Aromatic or alicyclic hydrocarbon resins, aromatic petroleum resins, chlorinated paraffins, paraffin waxes and the like can be mentioned, and these can be used alone or in combination.

(Charge control agent)
Known charge control agents can be used, such as nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxy amines, quaternary ammonium salts (fluorine-modified 4 Secondary ammonium salts or compounds, tungsten simple substances or compounds, fluorine activators, salicylic acid metal salts, and metal salts of salicylic acid derivatives. Specifically, Bontron 03 of a nigrosine dye, Bontron P-51 of a quaternary ammonium salt, Bontron S-34 of a metal-containing azo dye, E-82 of an oxynaphthoic acid metal complex, E-84 of a salicylic acid metal complex , Phenolic condensate E-89 (above, Orient Chemical Industries, Ltd.), quaternary ammonium salt molybdenum complex TP-302, TP-415 (above, Hodogaya Chemical Co., Ltd.), quaternary ammonium salt copy Charge PSY VP2038, 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) Manufactured), copper phthalocyanine, perylene, quinacridone, azo series Fee, a sulfonic acid group, a carboxyl group, and polymer compounds having a functional group such as quaternary ammonium salts. Of these, substances that control the negative polarity of the toner are particularly preferably used.
The amount of charge control agent used is determined by the type of binder resin, the presence or absence of additives used as necessary, and the toner production method including the dispersion method, and is not limited to a specific one. Preferably, it is 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 charge control agent is reduced, the electrostatic attraction with the developing roller is increased, the flowability of the developer is lowered, and the image density is lowered. Invite.

  The charge control agent and the release agent may be melt-kneaded together with the masterbatch and binder resin, or may be added when dissolved and dispersed in an organic solvent.

Next, a toner manufacturing method will be described. Here, although a preferable manufacturing method is shown, it is not limited to this.
(Toner production method)
1) A toner material solution is prepared by dispersing a colorant, unmodified polyester, a polyester prepolymer having an isocyanate group, and a release agent in an organic solvent.
The organic solvent is preferably volatile with a boiling point of less than 100 ° C. from the viewpoint of easy removal after toner base particle formation. Specifically, toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, ethyl acetate, methyl ethyl ketone, Methyl isobutyl ketone and the like can be used alone or in combination of two or more. In particular, aromatic solvents such as toluene and xylene and halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, chloroform, and carbon tetrachloride are preferable. The usage-amount of an organic solvent is 0-300 weight part normally with respect to 100 weight part of polyester prepolymers, Preferably it is 0-100 weight part, More preferably, it is 25-70 weight part.

2) The toner material liquid is emulsified in an aqueous medium in the presence of a surfactant and resin fine particles.
The aqueous medium may be water alone or an organic solvent such as alcohol (methanol, isopropyl alcohol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methyl cellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.). It may be included.
The amount of the aqueous medium used relative to 100 parts by weight of the toner material liquid is usually 50 to 2000 parts by weight, preferably 100 to 1000 parts by weight. If the amount is less than 50 parts by weight, the dispersion state of the toner material liquid is poor, and toner particles having a predetermined particle diameter cannot be obtained. If it exceeds 20000 parts by weight, it is not economical.

Further, in order to improve the dispersion in the aqueous medium, a dispersant such as a surfactant and resin fine particles is appropriately added.
As surfactants, anionic surfactants such as alkylbenzene sulfonates, α-olefin sulfonates, phosphate esters, alkylamine salts, amino alcohol fatty acid derivatives, polyamine fatty acid derivatives, amine salt types such as imidazoline, Quaternary ammonium salt type cationic surfactants such as alkyltrimethylammonium salts, dialkyldimethylammonium salts, alkyldimethylbenzylammonium salts, pyridinium salts, alkylisoquinolinium salts, benzethonium chloride, fatty acid amide derivatives, polyhydric alcohols Nonionic surfactants such as derivatives, for example, amphoteric surfactants such as alanine, dodecyldi (aminoethyl) glycine, di (octylaminoethyl) glycine and N-alkyl-N, N-dimethylammonium betaine And the like.

Further, by using a surfactant having a fluoroalkyl group, the effect can be obtained in a very small amount. Preferred anionic surfactants having a fluoroalkyl group include fluoroalkyl carboxylic acids having 2 to 10 carbon atoms and metal salts thereof, disodium perfluorooctanesulfonyl glutamate, 3- [ω-fluoroalkyl (C6-C11 ) Oxy] -1-alkyl (C3-C4) sodium sulfonate, 3- [ω-fluoroalkanoyl (C6-C8) -N-ethylamino] -1-propanesulfonic acid sodium, fluoroalkyl (C11-C20) carvone Acids and metal salts, perfluoroalkylcarboxylic acids (C7 to C13) and metal salts thereof, perfluoroalkyl (C4 to C12) sulfonic acids and metal salts thereof, perfluorooctanesulfonic acid diethanolamide, N-propyl-N- ( 2-Hydroxyethyl) Perful Olooctanesulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate, etc. Can be mentioned.
Product names include Surflon S-111, S-112, S-113 (Asahi Glass Co., Ltd.), Florard FC-93, FC-95, FC-98, FC-129 (Sumitomo 3M Co., Ltd.), Unidyne DS-101. DS-102 (manufactured by Daikin Industries, Ltd.), Megafac F-110, F-120, F-113, F-191, F-812, F-833 (manufactured by Dainippon Ink, Inc.), Xtop EF-102, 103, 104, 105, 112, 123A, 123B, 306A, 501, 201, 204 (manufactured by Tochem Products), and Fgentent F-100, F150 (manufactured by Neos).

  Further, as the cationic surfactant, aliphatic quaternary ammonium salts such as aliphatic primary, secondary or secondary amine acids having a fluoroalkyl group, and perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salts. , Benzalkonium salt, benzethonium chloride, pyridinium salt, imidazolinium salt, trade names include Surflon S-121 (manufactured by Asahi Glass), Florard FC-135 (manufactured by Sumitomo 3M), Unidyne DS-202 (Daikin Industries) Manufactured), MegaFuck F-150, F-824 (Dainippon Ink Co., Ltd.), Xtop EF-132 (Tochem Products Co., Ltd.), Footgent F-300 (Neos Co., Ltd.), and the like.

As the resin fine particles, the aforementioned substances can be used. In addition, inorganic compound dispersants such as tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, and hydroxyapatite can also be used.
As a dispersant that can be used in combination with the above resin fine particles and inorganic compound dispersant, the dispersed droplets may be stabilized by a polymer protective colloid. For example, acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid or maleic anhydride and other (meth) acrylic monomers containing hydroxyl groups Bodies such as acrylic acid-β-hydroxyethyl, methacrylic acid-β-hydroxyethyl, acrylic acid-β-hydroxypropyl, methacrylic acid-β-hydroxypropyl, acrylic acid-γ-hydroxypropyl, methacrylic acid-γ-hydroxy Propyl, acrylic acid-3-chloro-2-hydroxypropyl, methacrylic acid-3-chloro-2-hydroxypropyl, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, glycerol monomethacrylate Luric acid esters, N-methylol acrylamide, N-methylol methacrylamide, etc., vinyl alcohol or ethers with vinyl alcohol, such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, or compounds containing vinyl alcohol and a carboxyl group Esters such as vinyl acetate, vinyl propionate, vinyl butyrate, acrylamide, methacrylamide, diacetone acrylamide or their methylol compounds, acid chlorides such as acrylic acid chloride, methacrylic acid chloride, vinyl pyridine, vinyl pyrrolidone, vinyl Nitrogen compounds such as imidazole and ethyleneimine, or homopolymers or copolymers such as those having a heterocyclic ring thereof, polyoxyethylene, poly Xoxypropylene, polyoxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonylphenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, polyoxy Polyoxyethylenes such as ethylene nonylphenyl ester, celluloses such as methyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose can be used.

  The dispersion method is not particularly limited, and known equipment 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. Among these, the high-speed shearing method is preferable in order to make the particle size of the dispersion 2 to 20 μm. When a high-speed shearing disperser is used, the rotational speed is not particularly limited, but is usually 1000 to 30000 rpm, 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 during dispersion is usually 0 to 150 ° C. (under pressure), preferably 40 to 98 ° C.

3) At the same time as the preparation of the emulsion, the amines (B) are added to cause a reaction with the polyester prepolymer (A) having an isocyanate group.
This reaction involves molecular chain crosslinking and / or elongation. The reaction time is selected depending on the reactivity between the isocyanate group structure of the polyester prepolymer (A) and the amines (B), but is usually 10 minutes to 40 hours, preferably 2 to 24 hours. The reaction temperature is generally 0 to 150 ° C, preferably 40 to 98 ° C. Moreover, a well-known catalyst can be used as needed. Specific examples include dibutyltin laurate and dioctyltin laurate.

4) After completion of the reaction, the organic solvent is removed from the emulsified dispersion (reactant), washed and dried to obtain toner base particles.
In order to remove the organic solvent, the temperature of the entire system is gradually raised in a laminar stirring state, and after giving strong stirring in a certain temperature range, the solvent base is removed to produce spindle-shaped toner base particles. . Further, when an acid such as calcium phosphate salt or an alkali-soluble material is used as the dispersion stabilizer, the calcium phosphate salt is dissolved from the toner base particles by a method such as dissolving the calcium phosphate salt with an acid such as hydrochloric acid and washing with water. Remove. It can also be removed by operations such as enzymatic degradation.

  Either before or after the washing and solvent-removing steps, a step can be provided in which the emulsified dispersion is allowed to stand at a certain temperature for a certain period of time and the produced toner particles are aged. Thereby, toner particles having a desired particle diameter can be produced. The temperature of the aging step is preferably 25 to 50 ° C., and the time is preferably 10 minutes to 23 hours.

5) A charge control agent is injected into the toner base particles obtained above, and then inorganic fine particles such as silica fine particles and titanium oxide fine particles are externally added to obtain a toner.
The injection of the charge control agent and the external addition of the inorganic fine particles are performed by a known method using a mixer or the like.
Thereby, a toner having a small particle size and a sharp particle size distribution can be easily obtained. Furthermore, by giving strong agitation in the process of removing the organic solvent, the shape between the spherical shape and the spindle shape can be controlled, and the surface morphology is also controlled between the smooth shape and the plum dried shape. Can do.

The toner of the present invention can be mixed with a magnetic carrier and used as a two-component developer. In this case, the carrier to toner content ratio in the developer is preferably 1 to 10 parts by weight of toner with respect to 100 parts by weight of carrier. As the magnetic carrier, conventionally known ones such as iron powder, ferrite powder, magnetite powder, magnetic resin carrier having a particle diameter of about 20 to 200 μm can be used. Examples of the coating material include amino resins such as urea-formaldehyde resin, melamine resin, benzoguanamine resin, urea resin, polyamide resin, and epoxy resin. Polyvinyl and polyvinylidene resins such as acrylic resins, polymethyl methacrylate resins, polyacrylonitrile resins, polyvinyl acetate resins, polyvinyl alcohol resins, polyvinyl butyral resins, polystyrene resins and styrene acrylic copolymer resins, Halogenated olefin resins such as vinyl, polyester resins such as polyethylene terephthalate resin and polybutylene terephthalate resin, polycarbonate resins, polyethylene resins, polyvinyl fluoride resins, polyvinylidene fluoride resins, polytrifluoroethylene resins, polyhexafluoro Propylene resin, copolymer of vinylidene fluoride and acrylic monomer, copolymer of vinylidene fluoride and vinyl fluoride, tetrafluoroethylene and vinylidene fluoride and non- Monomers including a fluoro terpolymers such, and silicone resins. Moreover, you may contain electrically conductive powder etc. in coating resin as needed. As the conductive powder, metal powder, carbon black, titanium oxide, tin oxide, zinc oxide or the like can be used. These conductive powders preferably have an average particle diameter of 1 μm or less. When the average particle diameter is larger than 1 μm, it becomes difficult to control electric resistance.
In addition, the toner of the present invention can be used as a one-component magnetic toner by containing a magnetic material without using a carrier, or as a non-magnetic toner as a single component without containing a magnetic material.

An image forming apparatus using the toner of the present invention as a developer will be described.
FIG. 2 is a schematic diagram showing a configuration of an embodiment of the image forming apparatus according to the present invention. In the figure, reference numeral 100 is a copying apparatus main body, 200 is a paper feed table on which the copying apparatus is placed, 300 is a scanner mounted on the copying apparatus main body 100, and 400 is an automatic document feeder (ADF) mounted thereon.
The copying apparatus main body 100 has a tandem type in which four image forming units 18 each having various units for performing an electrophotographic process such as charging, developing, and cleaning are arranged in parallel around a photosensitive member 40 as a latent image carrier. An image forming apparatus 20 is provided. Above the tandem type image forming apparatus 20, there is provided an exposure apparatus 21 that exposes the photoreceptor 40 with laser light based on image information to form a latent image. Further, an intermediate transfer belt 10 made of an endless belt member is provided at a position facing each photoconductor 40 of the tandem type image forming apparatus 20. A primary transfer unit 62 for transferring the toner images of the respective colors formed on the photoconductor 40 to the intermediate transfer belt 10 is disposed at a position facing the photoconductor 40 via the intermediate transfer belt 10.
A secondary transfer device 22 that collectively transfers the toner images superimposed on the intermediate transfer belt 10 onto transfer paper conveyed from the paper feed table 200 is disposed below the intermediate transfer belt 10. The secondary transfer device 22 is configured by spanning a secondary transfer belt 24 that is an endless belt between two rollers 23, and is disposed by pressing against the support roller 16 via the intermediate transfer belt 10. The toner image on 10 is transferred onto a transfer sheet. A fixing device 25 for fixing the image on the transfer paper is provided beside the secondary transfer device 22.
The secondary transfer device 22 described above also has a sheet transport function for transporting the transfer paper after image transfer to the fixing device 25. Of course, a transfer roller or a non-contact charger may be arranged as the secondary transfer device 22, and in such a case, it is difficult to provide this sheet conveyance function together.
In the illustrated example, a reversing device 28 for reversing the transfer paper so as to record images on both sides of the transfer paper is provided below the secondary transfer device 22 and the fixing device 25 in parallel with the tandem image forming device 20 described above. .

  The developing device 4 of the image forming unit 18 uses a developer containing the above toner. In the developing device 4, the developer carrying member carries and conveys the developer, and an alternating electric field is applied at a position facing the photoconductor 40 to develop the latent image on the photoconductor 40. By applying the alternating electric field, the developer is activated, the charge amount distribution of the toner can be narrowed, and the developability can be improved.

  In addition, the photosensitive member 40 and the developing device are integrally supported, and the process cartridge can be formed to be detachable from the main body of the image forming apparatus. In addition, the process cartridge may include a charging unit and a cleaning unit.

The operation of the image forming apparatus is as follows.
First, a document is set on the document table 30 of the automatic document feeder 400, or the automatic document feeder 400 is opened and a document is set on the contact glass 32 of the scanner 300, and the automatic document feeder 400 is closed. Hold it down.
When a start switch (not shown) is pressed, when the document is set on the automatic document feeder 400, the document is transported and moved onto the contact glass 32, and then the document is set on the other contact glass 32. At that time, the scanner 300 is immediately driven, and the first traveling body 33 and the second traveling body 34 travel. Then, the first traveling body 33 emits light from the light source and further reflects the reflected light from the document surface toward the second traveling body 34 and reflects by the mirror of the second traveling body 34 and passes through the imaging lens 35. The document is placed in the reading sensor 36 and the original content is read.

  Further, one of the support rollers 14, 15 and 16 is rotationally driven by a drive motor (not shown), the other two support rollers are driven to rotate, and the intermediate transfer belt 10 is rotated and conveyed. At the same time, the individual image forming means 18 rotates the photoconductor 40 to form black, yellow, magenta, and cyan monochrome images on each photoconductor 40. Then, along with the conveyance of the intermediate transfer belt 10, these single color images are sequentially transferred to form a composite color image on the intermediate transfer belt 10.

On the other hand, one of the paper feed rollers 42 of the paper feed table 200 is selectively rotated to feed out the sheets from one of the paper feed cassettes 44 provided in the paper bank 43 in multiple stages, and the paper is separated one by one by the separation roller 45 and fed. The paper is put into a path 46, transported by a transport roller 47, led to a paper feed path 48 in the copying machine main body 100, and abutted against a registration roller 49 and stopped.
Alternatively, the sheet feed roller 50 is rotated to feed out the sheets on the manual feed tray 51, separated one by one by the separation roller 52, put into the manual feed path 53, and abutted against the registration roller 49 and stopped.
Then, the registration roller 49 is rotated in synchronization with the composite color image on the intermediate transfer belt 10, the sheet is fed between the intermediate transfer belt 10 and the secondary transfer device 22, and is transferred by the secondary transfer device 22. A color image is recorded on the sheet.

The image-transferred sheet is conveyed by the secondary transfer device 22 and sent to the fixing device 25. The fixing device 25 applies heat and pressure to fix the transferred image, and then the switching roller 55 is used to switch the discharge image. The paper is discharged at 56 and stacked on the paper discharge tray 57. Alternatively, it is switched by the switching claw 55 and put into the sheet reversing device 28, where it is reversed and guided again to the transfer position, and an image is recorded also on the back surface, and then discharged onto the discharge tray 57 by the discharge roller 56.
On the other hand, the intermediate transfer belt 10 after the image transfer is removed by the intermediate transfer belt cleaning device 17 to remove residual toner remaining on the intermediate transfer belt 10 after the image transfer, so that the tandem image forming apparatus 20 can prepare for the image formation again.

Example 1
As a toner, a mixture having the following formulation was kneaded under heating of two rolls, then cooled, coarsely pulverized, and pulverized and classified to obtain a toner having an average particle diameter of 6.2 μm.
Binder resin: Styrene / butyl acrylate copolymer 100 parts Colorant: Carbon black 11 parts Charge control agent: Salicylic acid derivative zinc salt 2 parts Release agent: Carnauba wax 4.5 parts For 100 parts by weight of the toner, A negatively charged developing toner A was prepared by mixing a fine silica powder having a particle size of about 16 nm treated with hexamethyldisilazane at a ratio of 0.7 parts at a peripheral speed of 20 m / sec with a Henschel mixer. . Further, with respect to 100 parts by weight of the toner, a fine titanium powder having a particle size of about 15 nm whose surface was treated with isobutyltrimethoxysilane was mixed at a rate of 0.5 part by a Henschel mixer at a peripheral speed of 20 m / sec. Thus, negatively charged developing toner B was prepared. Next, toner A and toner B were weighed at a ratio of 50:50, mixed at a peripheral speed of 20 m / sec by a Henschel mixer, and then passed through a 63 μm sieve to prepare a negatively chargeable developing toner C.

On the other hand, the carrier prepared the coating liquid by the following prescription.
Silicone resin SR2411 (solid content 20%, manufactured by Toray Dow Corning) 300 parts Toluene 1200 parts

The above liquid was put into a rotating disk type fluidized bed coating apparatus together with 5 kg of ferrite core material / carrier having an average particle diameter of 50 μm to coat the carrier. Thereafter, the coating was taken out from the apparatus and heated at 250 ° C. for 2 hours to age the film. Thereafter, the total amount of the toner over C and the carrier as toner over concentration of 4% has created a metered by the developer to be 1000 g. Table 1 shows an example in which the treatment agent, particle size, and mixing method of the external additive were changed.

  Imagio Neo 451 (Ricoh Copier) When a developer was set in this machine and an initial image was produced, a good image was obtained. Thereafter, 100,000 sheets of A4 paper were continuously fed by horizontal feeding. The results are shown in Table 2.

(Example 2)
Next, examples of color toners are shown.
(1) Production of masterbatch pigment Production example 1 of yellow toner masterbatch
Binder resin: 50 parts of polyester resin A (polyester resin synthesized from ethylene oxide adduct of bisphenol A, terephthalic acid, fumaric acid, softening point: 95 ° C.)
Colorant 50 parts (Imidazolone yellow pigment: CI Pigment Yellow 180)
30 parts of water
The raw materials were mixed with a Henschel mixer, and then kneaded for 45 minutes with two rolls set at a roll surface temperature of 130 ° C. to obtain a master batch pigment A.

2. Production example 2 of magenta toner master batch
Binder resin: 50 parts of polyester resin A (polyester resin synthesized from ethylene oxide adduct of bisphenol A, terephthalic acid, fumaric acid, softening point: 95 ° C)
Colorant 50 parts (Quinacridone-based magenta pigment: CI Pigment Red 122)
30 parts of water
The raw materials were mixed with a Henschel mixer, and then kneaded for 45 minutes with two rolls set at a roll surface temperature of 130 ° C. to obtain a master batch pigment B.
3. Cyan toner master batch production example 3
Binder resin: 50 parts of polyester resin A (polyester resin synthesized from ethylene oxide adduct of bisphenol A, terephthalic acid, fumaric acid, softening point: 95 ° C.)
50 parts of colorant (copper phthalocyanine cyan pigment: CI Pigment Blue 15: 3)
30 parts of water
The raw materials were mixed with a Henschel mixer, and then kneaded for 45 minutes with two rolls set at a roll surface temperature of 130 ° C. to obtain a master batch pigment C.
4). Black toner masterbatch production example 4
Binder resin: 50 parts of polyester resin A (polyester resin synthesized from ethylene oxide adduct of bisphenol A, terephthalic acid, fumaric acid, softening point: 95 ° C.)
50 parts of colorant (carbon black pigment: CI Pigment Bullack 1)
30 parts of water
The raw materials were mixed with a Henschel mixer, and then kneaded for 45 minutes with two rolls set at a roll surface temperature of 130 ° C. to obtain a master batch pigment D.

(2) Preparation of toner Yellow, magenta, cyan and black toners were prepared for each master batch pigment A, B, C 1 and D 2 according to the following formulation.
Binder resin: 100 parts of polyester resin A (polyester resin synthesized from ethylene oxide adduct of bisphenol A, terephthalic acid, fumaric acid, softening point: 95 ° C.)
Colorant: Masterbatch pigment (each AD) 15 parts
Release agent (Carnauba wax: melting point 92 ° C., Mw / Mn 1.1) 5 parts Charge control agent (salicylic acid derivative zinc salt) 2.5 parts

  The raw materials were mixed with a Henschel mixer and then melt-kneaded with a biaxial kneader set at 110 ° C. The kneaded product is cooled with water, coarsely pulverized by a cutter mill, pulverized by a fine pulverizer using a jet stream, and then the base particles of yellow, magenta, cyan, and black toners having a particle size of 6.1 μm using an air classifier. It was created. With respect to 100 parts by weight of each of the yellow, magenta, cyan, and black toners, a silica fine powder having a particle diameter of about 16 nm, the surface of which is treated with hexamethyldisilazane, at a rate of 0.7 parts by a Henschel mixer. By mixing at 20 m / sec, negatively chargeable developing yellow A, magenta B, cyan C and black D toner were prepared. Further, with respect to 100 parts by weight of the toner, titanium fine powder having a particle size of about 15 nm, the surface of which was treated with isobutyltrimethoxysilane, was mixed at a rate of 0.5 part by a Henschel mixer at a peripheral speed of 20 m / sec. Thus, negatively developing yellow E, magenta F, cyan G and black H.tona were prepared. Next, yellow toner A and yellow toner E were weighed at a ratio of 50:50, mixed with a Henschel mixer at a peripheral speed of 20 m / sec, and then passed through a 63 μm sieve to prepare negatively chargeable developing yellow toner I. Next, magenta toner B and magenta toner F were weighed at a ratio of 50:50, mixed with a Henschel mixer at a peripheral speed of 20 m / sec, and then passed through a 63 μm sieve to prepare negatively charged developing magenta toner J. . Next, cyan toner C and cyan toner G were weighed at a ratio of 50:50, mixed with a Henschel mixer at a peripheral speed of 20 m / sec, and then passed through a 63 μm sieve to produce negatively chargeable developing cyan toner K. Next, the black toner D and the black toner H were weighed at a ratio of 50:50, mixed with a Henschel mixer at a peripheral speed of 20 m / sec, and passed through a 63 μm sieve to prepare a negatively chargeable developing black toner L. Table 1 shows examples of changing the processing agent, particle size, and mixing method of the external additive.

On the other hand, the carrier prepared the coating liquid by the following prescription.
Silicon resin SR2411 (manufactured by Tore Dow Corning) 300 parts Toluene 1200 parts The above liquid was placed in a rotating disk type fluidized bed coating apparatus together with 5 kg of ferrite core material / carrier having an average particle diameter of 50 μm to coat the carrier. Thereafter, the coating was taken out from the apparatus and heated at 250 ° C. for 2 hours to age the film. Thereafter, the yellow I of the so toner over concentration of 5% magenta J, cyan G and black L · toner yellow metered so that the total amount of the carrier is 1000 g, magenta, cyan and black A toner developer was prepared.

  When a developer was set in the machine shown in FIG. 2 and an initial image was produced, a good image was obtained. Thereafter, 100,000 sheets of A4 paper were continuously fed by horizontal feeding. The results are shown in Table 2.

(Examples 3 to 9)
Table 1 shows an example in which the yellow, magenta, cyan and black toner base particles are the same as the yellow, magenta, cyan and black toners of Example 2, but the processing agent, particle size and mixing method of the external additive are changed. Shimese. The results are shown in Table 2.

(Example 10)
The yellow, magenta, cyan, and black toner bases use the base particles of each color in Example 2. As the external additive, the external additive 1 of Example 7 is used. In addition, the external additives of yellow, magenta, cyan and black toner are newly mixed using the toner base of Example 2 according to the following prescription. To 100 parts of the toner base of each color, a silica base material treated with hexamethyldisilazane is mixed with a fine powder having a particle size of 15 nm at a ratio of 1.6 parts using a Henschel mixer at a peripheral speed of 20 mm / sec. Negatively charged toners of yellow, magenta, cyan and black toners were prepared. Further, the toner base of Example 2 is used to mix external additives of yellow, magenta, cyan, and black toner.
To 100 parts of the toner base of each color, yellow is obtained by mixing a fine powder having a particle size of 15 nm treated with isobutyltrimethoxysilane on a titanium base at a rate of 0.6 parts with a Henschel mixer at a peripheral speed of 20 mm / sec. Negatively chargeable toners of magenta, cyan and black toners were prepared. Each color toner obtained by mixing these three types of external additives was prepared by adding the external additive 1 / silica substrate of Example 7 with hexamethyldisilazane to each color and isobutyltrimethoxysilane on the titanium substrate. The processed external additive was weighed at a ratio of 60/30/10, mixed with a Henschel mixer at a peripheral speed of 20 mm / sec, and then passed through a 63 μm sieve to prepare a negatively chargeable developing toner.
Using the carrier of Example 2, the developer is prepared for yellow, magenta, cyan and black toners by weighing the total amount of toner and carrier to 1000 g so that the toner density is 5%. did. Table 1 shows examples of changing the processing agent, particle size, and mixing method of the external additive.

  When a developer was set in the machine shown in FIG. 2 and an initial image was produced, a good image was obtained. Thereafter, 100,000 sheets of A4 paper were continuously fed by horizontal feeding. The results are shown in Table 2.

(Example 11)
As the base particles of yellow, magenta, cyan, and black toner, the base particles of each color of Example 2 are used. As the external additive, the external additive 2 of Example 9 is used. Then, yellow, magenta, cyan and black toner external additives are newly mixed according to the following prescription. A negative chargeable toner of each color was prepared by mixing 0.8 parts of fluororesin fine particles (particle size 50 nm) with a Henschel mixer at a peripheral speed of 20 m / sec. The toner mixed with this external additive and the toner of each color external additive 2 of Example 9 were weighed at a ratio of 50:50, mixed at a circumference of 20 m / sec with a Henschel mixer, and then passed through a 63 μm sieve to be negatively charged. Toner for development was prepared. The carrier using the carrier of Example 2, the yellow total amount of toner and carrier as toner over concentration of 5% by weigh to be 1000 g, magenta, cyan and black toner developer Created.

  When a developer was set in the machine shown in FIG. 2 and an initial image was produced, a good image was obtained. Thereafter, 100,000 sheets of A4 paper were continuously fed by horizontal feeding. The result is shown in Table 2.

Example 12
As the base particles of yellow, magenta, cyan, and black toner, the base particles of each color of Example 2 are used. As the external additive, the external additive 2 of Example 7 and the external additive 1 and external additive 2 of Example 9 are used. The toners with external additives for each color were weighed at a ratio of 40/20/40, mixed with a Henschel mixer at a peripheral speed of 20 m / sec, and then passed through a 63 μm sieve to prepare a negatively chargeable developing toner. The carrier using the carrier of Example 2, the yellow total amount of toner and carrier as toner over concentration of 5% by weigh to be 1000 g, magenta, cyan and black toner developer Created. Table 1 shows examples of changing the processing agent, particle size, and mixing method of the external additive.

  When a developer was set in the machine shown in FIG. 2 and an initial image was produced, a good image was obtained. Thereafter, 100,000 sheets of A4 paper were continuously fed by horizontal feeding. The results are shown in Table 2.

(Example 13)
Further, an example using a toner by a polymerization method is shown.
1. Black toner production example-Synthesis of organic fine particle emulsion-
In a reaction vessel equipped with a stir bar and a thermometer, 683 parts of water, 11 parts of sodium salt of ethylene oxide methacrylate adduct sulfate (Eleminol RS-30; manufactured by Sanyo Chemical Industries), 166 parts of methacrylic acid, butyl acrylate When 110 parts and 1 part of ammonium persulfate were charged and stirred at 3800 rpm for 30 minutes, a white emulsion was obtained. The system was heated to raise the system temperature to 75 ° C. and reacted for 4 hours. Further, 30 parts of a 1% ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 6 hours to obtain an aqueous dispersion of a vinyl resin (methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt copolymer). A liquid [fine particle dispersion 1] was obtained. The volume average particle diameter of [fine particle dispersion 1] measured by a laser diffraction particle size distribution analyzer (LA-920; manufactured by Shimadzu Corp.) was 110 nm. A portion of [Fine Particle Dispersion 1] was dried to isolate the resin component. The Tg of the resin was 58 ° C., and the weight average molecular weight was 130,000.

-Adjustment of aqueous phase-
990 parts of water, 83 parts of [fine particle dispersion 1], 37 parts of a 48.3% aqueous solution of sodium dodecyl diphenyl ether disulfonate (Eleminol MON-7; manufactured by Sanyo Kasei Kogyo Co., Ltd.) and 90 parts of ethyl acetate were mixed and stirred. A liquid was obtained. This is designated as [Aqueous Phase 1].

~ Synthesis of low molecular weight polyester ~
In a reaction vessel equipped with a condenser, a stirrer and a nitrogen inlet tube, 229 parts of bisphenol A ethylene oxide 2-mole adduct, 529 parts of bisphenol A propylene oxide 3-mole adduct, 208 parts terephthalic acid, 46 parts adipic acid and dibutyl Add 2 parts of tin oxide, react at normal pressure and 230 ° C for 7 hours, and further react for 5 hours at 10-15 mmHg reduced pressure, then add 44 parts of trimellitic anhydride to the reaction vessel at normal pressure and 180 ° C. By reacting for 3 hours, [low molecular weight polyester 1] was obtained. [Low molecular polyester 1] had a number average molecular weight of 2,300, a weight average molecular weight of 6,700, Tg of 43 ° C., and an acid value of 25.

~ Synthesis of intermediate polyester ~
In a reaction vessel equipped with a condenser, a stirrer and a nitrogen introduction tube, 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, 22 parts of trimellitic anhydride Then, 2 parts of dibutyltin oxide was added, reacted at 230 ° C. under normal pressure for 7 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 2200, a weight average molecular weight of 9700, Tg of 54 ° C., an acid value of 0.5, and a hydroxyl value of 52.
Next, 410 parts of [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. Polymer 1] was obtained. [Prepolymer 1] had a free isocyanate weight percentage 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 4 and a half hours to obtain [ketimine compound 1]. The amine value of [ketimine compound 1] was 417.
~ Master batch synthesis ~
Add 1200 parts of water, 540 parts of carbon black (Printex 35; manufactured by Dexa) (DBP oil absorption = 42 ml / 100 mg, pH = 9.5), 1200 parts of polyester resin, and mix with a Henschel mixer (manufactured by Mitsui Mining). The mixture was kneaded at 130 ° C. for 1 hour using two rolls, rolled and cooled, and pulverized with a pulverizer to obtain [Masterbatch 1].

~ Preparation of oil phase ~
In a container equipped with a stir bar and a thermometer, 378 parts of [Low molecular polyester 1], 100 parts of Carnauba WAX, and 947 parts of ethyl acetate were charged, heated to 80 ° C. with stirring, and kept at 80 ° C. for 5 hours. Cooled to 30 ° C. in 1 hour. Next, 500 parts of [Masterbatch 1] and 500 parts of ethyl acetate were placed in a container and mixed for 1 hour to obtain [Raw material solution 1].
[Raw Material Solution 1] 1324 parts were transferred to a container, and using a bead mill (Ultra Visco Mill; manufactured by Imex Co., Ltd.), a liquid feeding speed of 1 kg / hr, a disk peripheral speed of 6 m / sec, and 0.5 mm zirconia beads were 80% by volume. Carbon black and WAX were dispersed under conditions of filling and 3 passes. Next, 1324 parts of a 65% ethyl acetate solution of [low molecular weight polyester 1] was added, followed by two passes with a bead mill under the above conditions to obtain [Pigment / WAX Dispersion 1]. The solid content concentration of [Pigment / WAX Dispersion 1] (130 ° C., 30 minutes) was 50%.

~ Emulsification, solvent removal ~
[Pigment / WAX Dispersion 1] 749 parts, [Prepolymer 1] 115 parts, [Ketimine Compound 1] 2.9 parts in a container, and 2 at 5,000 rpm with a TK homomixer (manufactured by Tokushu Kika) After mixing for 1 minute, 1200 parts of [Aqueous Phase 1] was added to the container and mixed with a TK homomixer at 13,000 rpm for 25 minutes to obtain [Emulsion Slurry 1].
[Emulsion slurry 1] 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 7 hours to obtain [Dispersion slurry 1].

~ Washing, drying ~
[Dispersion Slurry 1] After filtering 100 parts under reduced pressure,
(1): 100 parts of ion-exchanged water was added to the filter cake, mixed with a TK homomixer (10 minutes at 12,000 rpm), and then filtered.
(2): 100 parts of a 10% aqueous sodium hydroxide solution was added to the filter cake of (1), mixed with a TK homomixer (30 minutes at 12,000 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 (rotation speed: 12,000 rpm for 10 minutes), and then filtered.
(4): Add 300 parts of ion-exchanged water to the filter cake of (3), mix with a TK homomixer (10 minutes at 12,000 rpm) and then filter twice to obtain [filter cake 1]. It was.
[Filter cake 1] was dried at 45 ° C. for 48 hours in a circulating drier. 100 parts of this base toner was mixed with a mixer at a ratio of 0.6 part of zinc salicylate (E-84; manufactured by Orient Chemical Co., Ltd.). And sieved with a mesh of 75 μm, weight average particle size (D4) 6.1 μm, number average particle size (Dn) 5.5 μm, D4 / Dn = 1.11, average circularity 0.97, shape factor SF− A toner having 1 = 135, shape factor SF-2 = 118, minor axis (r2) / major axis (r1) = 0.8, and thickness (r3) / minor axis (r2) = 0.9 was obtained.

~ External additive treatment ~
A black toner was prepared by mixing external additives with 100 parts by weight of the toner in the same manner as in Example 12.

2. Example of production of yellow toner In the synthesis of the masterbatch, C.I. I. A yellow toner was prepared in the same manner as the black toner example, except that CI Pigment Yellow 180 (PV Fast Yellow HG; manufactured by Clariant) was used.
The base toner has a weight average particle diameter (D4) of 6.0 μm, a number average particle diameter (Dn) of 5.4 μm, D4 / Dn = 1.11, an average circularity of 0.97, a shape factor SF-1 = 132, and a shape. The coefficient SF-2 was 115, the minor axis (r2) / major axis (r1) was 0.8, and the thickness (r3) / minor axis (r2) was 0.9.
~ External additive treatment ~
An external additive was mixed with 100 parts by weight of the toner in the same manner as in Example 12 to produce a yellow toner.

3. Production example of magenta toner In the synthesis of the masterbatch, C.I. I. A magenta toner was prepared in the same manner as the black toner example except that CI Pigment Red 122 (Hostaperm Pink E; manufactured by Clariant) was used.
The base toner has a weight average particle diameter (D4) of 6.5 μm, a number average particle diameter (Dn) of 5.6 μm, D4 / Dn = 1.16, an average circularity of 0.96, a shape factor SF-1 = 137, and a shape. The coefficient SF-2 was 117, the minor axis (r2) / major axis (r1) = 0.8, and the thickness (r3) / minor axis (r2) = 0.9.
~ External additive treatment ~
An external additive was mixed in the same manner as in Example 12 with respect to 100 parts by weight of the toner to prepare a magenta toner.

4). Example of Cyan Toner Production In the synthesis of a masterbatch, C.I. I. A cyan toner was prepared in the same manner as in the black toner example, except that CI Pigment Blue 15: 3 (Lionol Blue FG-7351; manufactured by Toyo Ink Co., Ltd.) was used.
The base toner has a weight average particle diameter (D4) of 6.2 μm, a number average particle diameter (Dn) of 5.5 μm, D4 / Dn = 1.13, an average circularity of 0.97, a shape factor SF-1 = 134, and a shape. The coefficient SF-2 was 115, the minor axis (r2) / major axis (r1) was 0.8, and the thickness (r3) / minor axis (r2) was 0.9.
~ External additive treatment ~
In the same manner as in Example 12, external additives were mixed with 100 parts by weight of the toner to prepare a cyan toner.

The toners with external additives for each color were weighed at a ratio of 40/20/40, mixed with a Henschel mixer at a peripheral speed of 20 m / sec, and then passed through a 63 μm sieve to prepare a negatively chargeable developing toner. The carrier using the carrier of Example 2, the yellow total amount of toner and carrier as toner over concentration of 5% by weigh to be 1000 g, magenta, cyan and black toner developer Created. Table 1 shows examples of changing the processing agent, particle size, and mixing method of the external additive.

  When a developer was set in the machine shown in FIG. 2 and an initial image was produced, a good image was obtained. Thereafter, 100,000 sheets of A4 paper were continuously fed by horizontal feeding. The results are shown in Table 2.

(Comparative Example 1)
In Example 1, the toner base is that of Example 1. 100 parts by weight of the toner, 0.7 parts of silica fine powder having a particle diameter of about 120 nm treated with hexamethyldisilazane on the surface and titanium fine powder having a particle diameter of about 15 nm treated with isobutyltrimethoxysilane on the surface Two types of external additives were mixed together at a ratio of 0.5 part with a Henschel mixer at a peripheral speed of 20 m / sec to prepare a negatively chargeable developing toner. Then, after mixing, it was passed through a 63 μm sieve to prepare a negatively chargeable developing toner. Meanwhile, the carrier is the total amount of the toner over the carrier as toner over concentration of 4% has created a metered by the developer so as to 1000g using objects to Example 1. Table 1 shows examples of changing the processing agent, particle size, and mixing method of the external additive.

  When a developer was set in the machine shown in FIG. 2 and an initial image was produced, a good image was obtained. Thereafter, 100,000 sheets of A4 paper were continuously fed by horizontal feeding. The results are shown in Table 2.

In all of Examples 1 to 13, there was no filming on the photosensitive member, cleaning property, carrier contamination, and the like as compared with the simultaneous addition of Comparative Example 1. Furthermore, it was stable not only at the initial stage but also after printing 100,000 sheets.
In addition, the pumping amount with respect to the developing sleeve in the developing device was stable over a long period of time.
Further, there was no contamination in the fixing device, and it was stable not only at the initial stage but also after printing 100,000 sheets.

FIG. 6 is a diagram schematically illustrating the shape of a toner, and is a diagram for explaining a shape factor SF-1 and a shape factor SF-2. 1 is a schematic diagram illustrating a configuration of an embodiment of an image forming apparatus according to the present invention.

Explanation of symbols

4 Developing device 10 Intermediate transfer belt (intermediate transfer member)
18 Image forming means 21 Exposure device 25 Fixing device 40 Photosensitive member (latent image carrier)
22 Secondary transfer device 62 Primary transfer means 100 Copier main body 200 Paper feed table 300 Scanner 400 Automatic document feeder

Claims (7)

A method for producing a toner comprising at least two types of toner particles having an external additive added to the surface of toner base particles comprising at least a binder resin and a colorant,
One kind of base particle is used as the base particle,
Before SL toner base particles, were added and mixed alone respectively at least two kinds of external additives, to create at least two types of toner particles,
A method for producing toner , comprising mixing at least two kinds of toner particles produced . The toner production method according to claim 1, wherein:
The toner production method, wherein the at least two types of external additives have different number average particle diameters. The toner production method according to claim 2,
The at least two types of external additives are at least an external additive having a number average particle diameter in the range of 75 to 500 nm and an external additive having a number average particle diameter in the range of 5 to 20 nm. Toner manufacturing method . The toner production method according to claim 2,
The at least two types of external additives include at least an external additive having a number average particle size in the range of 75 to 500 nm, an external additive having a number average particle size in the range of 20 to 75 nm, and a number average particle size of 5. A method for producing a toner, comprising: an external additive in a range of ˜20 nm. In the toner production method according to claim 1 or 2,
The method for producing toner , wherein the at least two kinds of external additives are different in material. The method for producing a toner according to claim 5, wherein
The toner production method, wherein the at least two kinds of external additives are inorganic fine particles and / or organic fine particles. In the toner manufacturing method according to claim 5 or 6,
The method for producing toner , wherein the at least two kinds of external additives are inorganic fine particles of silica, titania, and alumina.

Images