JP4419866B2 - Toner for electrostatic latent image development, developer and image forming method - Google Patents

Description

  The present invention relates to a toner, a developer, and an image forming method used for developing an electrostatic latent image in electrophotography and electrostatic recording.

  According to the electrophotographic method, an electrostatic latent image formed on an image carrier (photoconductor) is developed with toner containing a colorant to form a toner image, and the obtained toner image is transferred onto a transfer member. An image can be obtained by transferring and fixing with a heat roll or the like. The image carrier is cleaned again to form an electrostatic latent image.

  Hitherto, there has been a high demand for high functionality in the electrophotographic market, and in particular with regard to full-color image quality, high-quality quality close to high-quality printing and silver salt photography is desired. Therefore, in recent electrophotographic methods, a toner having a small particle diameter is used in order to perform faithful color reproduction.

  When a toner having a small particle diameter is used, faithful color reproduction can be performed, but transfer performance may be deteriorated, and it may be difficult to stably obtain high image quality over a long period of time. Accordingly, attempts have been made to improve transfer efficiency by using toner having a spherical shape (spherical toner). When spherical toner is used, toner transfer efficiency is improved and high image quality can be obtained.

  As described above, even when spherical toner having a small particle diameter is used, the toner remains on the image carrier (photoconductor) slightly after transfer. It has been attempted to remove the residual toner from the image carrier by a cleaning means such as a cleaning blade that rubs the surface of the image carrier to scrape the residual toner. In addition, since a small particle size and spherical toner easily slips between the cleaning blade and the photosensitive member, for example, an external additive of toner (volume average particle size of 3 to 7 μm) is used in order to easily collect the residual toner. Inorganic particles (number average particle size of 80 to 800 nm and content of particles of 1000 nm or more is 20 number% or less) have been tried to improve the cleaning performance (see Patent Document 1). Since the inorganic particles have a large particle size, they are easily released from the toner. The released inorganic particles block the gap between the cleaning blade and the image carrier, and other fine particles such as toner are formed on the cleaning blade and the image carrier. It prevents the passage of the gap and improves the cleaning property.

  Furthermore, in order to reduce the frictional force between the surface of the image carrier and the cleaning blade, a lubricant such as zinc stearate is supplied onto the image carrier by a predetermined lubricant supply device (see Patent Document 2). In addition, a lubricant is applied on the photosensitive member by a predetermined lubricant application means, and a lubricant powder is externally added to the toner to improve the cleaning performance (see Patent Document 3). When the lubricant is supplied between the image carrier and the cleaning blade, the frictional force between the image carrier and the cleaning blade decreases, and the image carrier surface and the cleaning blade wear due to friction between the two. And the cleaning performance is improved.

JP-A-10-207113 Japanese Patent Laid-Open No. 11-344904 JP 2003-316201 A

  When inorganic particles having a large particle size are used as an external additive for toner as described above, the inorganic particles have a large true specific gravity and are easily released from the toner, so that they enter between the cleaning blade and the image carrier, While the fine particles function to prevent the fine particles from passing between them, the inorganic particles have a problem that the surface of the image carrier is damaged and filming is likely to occur.

  Further, when a predetermined lubricant supply device (means) is used to reduce the frictional force between the image carrier and the cleaning blade, it is necessary to secure a space for installing the device, and the size of the device is reduced. It becomes a problem from the viewpoint of conversion.

  Further, when an image is formed using a toner having lubricant particles as an external additive, the lubricant particles are released from the toner and supplied to the cleaning blade in the cleaning step. However, in that case, the lubricant particles may be released from the toner outside the cleaning step, and a method of supplying the lubricant to the cleaning blade more reliably is desired.

Therefore, the present invention provides the following inventions as means for solving the above problems.
<1> The electrostatic latent image formed on the image carrier is developed with a developer containing toner to form a toner image. After the toner image is transferred, the toner remaining on the image carrier is removed with a cleaning blade. An electrostatic latent image developing toner used in an image forming method having a cleaning step for removing, wherein the electrostatic latent image developing toner comprises toner particles containing at least a binder resin and a colorant, and an external additive The toner particles have a volume average particle diameter of 2 μm to 10 μm, and the external additive has a volume average particle diameter of 100 nm or more and not more than the volume average particle diameter of the toner particles, and has a porosity of 40% to 80%. inorganic hollow particles child or Rannahli, electrostatic latent image developing toner further external additive is characterized in that satisfy the following condition.
[Equation 5]
0.2 ≦ D50dest / D50ini ≦ 0.85
(Here, D50ini represents the volume average particle diameter D50 of the external additive adhering to the toner particles in the toner before development. D50dest represents when the residual toner on the image carrier is removed by the cleaning blade. (This represents the volume average particle diameter D50 of the external additive present in the tip portion.)

  <2> In the electrostatic latent image developing toner according to <1>, it is desirable to use one or more inorganic particles in combination as an external additive. For example, when two types of inorganic particles are used in combination, it is desirable to use inorganic particles having a volume average particle size of 5 nm to 30 nm and inorganic particles having a volume average particle size of 40 nm to 100 nm.

  <3> In the electrostatic latent image developing toner according to <1>, the average shape factor SF1 of the toner particles is preferably in the range of 100 to 140.

<4> The present invention also provides the following inventions as means for solving the above problems.
A cleaning process in which the electrostatic latent image formed on the image carrier is developed with a developer containing toner to form a toner image, the toner image is transferred, and then the toner remaining on the image carrier is removed with a cleaning blade. A toner for developing an electrostatic latent image used in an image forming method comprising: toner particles containing at least a binder resin and a colorant; and an external additive. The volume average particle diameter of the toner particles is 2 μm to 10 μm, and the external additive is an inorganic hollow having a volume average particle diameter of 100 nm or more and not more than the volume average particle diameter of the toner particles, and a porosity of 40% to 80%. or particles lubricant encapsulated allowed lubricant containing inorganic particles child Rannahli, electrostatic latent image developing toner further external additive is characterized in that satisfy the following condition.
[Equation 6]
0.2 ≦ D50dest / D50ini ≦ 0.85
(Here, D50ini represents the volume average particle diameter D50 of the external additive adhering to the toner particles in the toner before development. D50dest represents when the residual toner on the image carrier is removed by the cleaning blade. (This represents the volume average particle diameter D50 of the external additive present in the tip portion.)

  <5> In the electrostatic latent image developing toner according to <4>, it is desirable to use one or more inorganic particles in combination as an external additive. For example, when two types of inorganic particles are used in combination, it is desirable to use inorganic particles having a volume average particle size of 5 nm to 30 nm and inorganic particles having a volume average particle size of 40 nm to 100 nm.

  <6> In the electrostatic latent image developing toner according to <4>, the average shape factor SF1 of the toner particles is preferably in the range of 100 to 140.

  <7> Furthermore, the present invention provides an electrostatic latent image developing developer comprising the electrostatic latent image developing toner according to any one of <1> to <6> and a carrier.

<8> Furthermore, the present invention provides the following inventions.
The electrostatic latent image formed on the image carrier is developed with a developer containing toner to form a toner image. After the toner image is transferred, the toner remaining on the image carrier is removed with a cleaning blade. In the image forming method having a cleaning step, the toner comprises toner particles containing at least a binder resin and a colorant, and an external additive, and the toner particles have a volume average particle diameter of 2 μm to 10 μm. additive has a volume average particle diameter or less of a volume average particle diameter 100nm or more and toner particles, the void ratio of 40% to 80% inorganic hollow particles child or Rannahli further external additive is satisfying electrostatic below An image forming method using a toner for developing an electrostatic latent image.
[Equation 7]
0.2 ≦ D50dest / D50ini ≦ 0.85
(Here, D50ini represents the volume average particle diameter D50 of the external additive adhering to the toner particles in the toner before development. D50dest represents when the residual toner on the image carrier is removed by the cleaning blade. (This represents the volume average particle diameter D50 of the external additive present in the tip portion.)

<9> Furthermore, the present invention provides the following inventions.
The electrostatic latent image formed on the image carrier is developed with a developer containing toner to form a toner image. After the toner image is transferred, the toner remaining on the image carrier is removed with a cleaning blade. In the image forming method having a cleaning step, the toner comprises toner particles containing at least a binder resin and a colorant, and an external additive, and the toner particles have a volume average particle diameter of 2 μm to 10 μm. additive has a volume average particle diameter or less of a volume average particle diameter of 100nm or more and toner particles, or void ratio of 40% to 80% of inorganic hollow particles were encapsulated lubricant lubricant-containing inorganic particles child Rannahli Furthermore, the image forming method, wherein the external additive is an electrostatic latent image developing toner that satisfies the following conditions.
[Equation 8]
0.2 ≦ D50dest / D50ini ≦ 0.85
(Here, D50ini represents the volume average particle diameter D50 of the external additive adhering to the toner particles in the toner before development. D50dest represents when the residual toner on the image carrier is removed by the cleaning blade. (This represents the volume average particle diameter D50 of the external additive present in the tip portion.)

  <10> In the image forming method according to <9>, it is preferable that one or more inorganic particles are further used in combination as an external additive for the toner for developing an electrostatic latent image. For example, when two types of inorganic particles are used in combination, it is desirable to use inorganic particles having a volume average particle size of 5 nm to 30 nm and inorganic particles having a volume average particle size of 40 nm to 100 nm.

  According to the present invention, it is possible to provide a toner for developing an electrostatic latent image, a developer for developing an electrostatic latent image, and an image forming method capable of ensuring stable cleaning properties over a long period of time.

[Electrostatic latent image developing toner]
The electrostatic latent image developing toner (hereinafter simply referred to as toner) includes at least toner particles including a binder resin and a colorant, and an external additive externally added to the toner particles. The toner particles include at least a binder resin and a colorant, and include a release agent, a charge control agent, and the like as necessary.

  Examples of the binder resin include styrenes such as styrene and chlorostyrene, monoolefins such as ethylene, propylene, butylene, and isoprene, vinyl esters such as vinyl acetate, vinyl propionate, vinyl benzoate, and vinyl butyrate, acrylics, and the like. Α-methylene aliphatic monocarboxylic acid esters such as methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, dodecyl methacrylate Homopolymers and copolymers of vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl butyl ether, vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone and vinyl isopropenyl ketone It can be. Particularly representative binder resins include polystyrene, styrene-alkyl acrylate copolymer, styrene-alkyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer. Examples thereof include a polymer, polyethylene, and polypropylene. Further examples include polyester, polyurethane, epoxy resin, silicone resin, polyamide, modified rosin, paraffin wax and the like.

  Coloring agents include magnetic powders such as magnetite and ferrite, carbon black, aniline blue, caryl blue, chrome yellow, ultramarine blue, DuPont oil red, quinoline yellow, methylene blue chloride, phthalocyanine blue, malachite green oxalate, and lamp black. Rose Bengal, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 57: 1, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 17, C.I. I. Pigment blue 15: 1, C.I. I. Pigment Blue 15: 3 can be exemplified as a representative one.

  Typical examples of the release agent include low molecular weight polyethylene, low molecular weight polypropylene, Fischer tropic wax, montan wax, carnauba wax, rice wax, and candelilla wax.

  As the charge control agent, known charge control agents can be used, but it is possible to use an azo metal complex compound, a metal complex compound of salicylic acid, or a resin type charge control agent containing a polar group. it can.

  The toner particles are produced by kneading, pulverizing, and classifying a binder resin, a colorant, a release agent, and, if necessary, a charge control agent. Method of changing shape by force or thermal energy, emulsion polymerization of polymerizable monomer of binder resin, dispersion of formed dispersion, colorant, release agent, and charge control agent as required Emulsion polymerization agglomeration method to obtain toner particles by mixing and agglomerating and heat fusing the liquid, polymerizable monomer and colorant, release agent, and charge control agent if necessary Suspension polymerization method in which the solution is suspended in an aqueous solvent for polymerization, a binder resin and a colorant, a release agent, and if necessary, a solution such as a charge control agent is suspended in an aqueous solvent for granulation A suspension method or the like can be used. In addition, a manufacturing method may be performed in which the toner obtained by the above method is used as a core, and agglomerated particles are further adhered and heat-fused to give a core-shell structure.

  The volume average particle diameter of the toner particles is desirably 2 μm to 10 μm. The volume average particle diameter of the toner particles was measured using a Coulter Multisizer-II type (manufactured by Beckman-Coulter). In the measurement, 0.5 mg to 50 mg of a measurement sample was added to 2 ml of an aqueous solution containing a surfactant as a dispersant (preferably a 5% aqueous solution of sodium alkylbenzenesulfonate), and this aqueous solution was further added to an electrolytic solution (ISOTON-II). (Beckman-Coulter)) 100 ml was added to prepare a measurement sample suspension. The suspension is subjected to a dispersion treatment with an ultrasonic disperser for 1 minute, and the particle size distribution of particles having a diameter of 2 to 60 μm is measured using the call counter TA-II type with an aperture diameter of 100 μm. The number average distribution was determined. The number of particles to be measured was 50,000.

  In the present embodiment, when the volume average particle diameter is 2 μm or more (for example, an external additive having a volume average particle diameter of 2 μm or more), the measurement of the volume average particle diameter describes other measurement methods. Unless otherwise noted, the test was performed using the Coulter Multisizer II type.

  In the present embodiment, in the case of particles having a volume average particle diameter of less than 2 μm (for example, an external additive having a volume average particle diameter of less than 2 μm), other measurement methods are described for measuring the volume average particle diameter. Unless otherwise indicated, it was measured using a laser diffraction particle size distribution analyzer (LA-700: Horiba Seisakusho). In the measurement, ion-exchanged water is added to a sample dispersion prepared to have a solid content of about 2 g to obtain a 40 ml sample dispersion. This sample dispersion is put into a predetermined cell until it reaches a predetermined concentration, and then the cell is left for 2 minutes to stabilize the concentration of the sample dispersion in the cell, and then the sample dispersion is used for measurement. The obtained volume average particle diameter for each channel is accumulated from the smaller volume average particle diameter, and the place where the accumulation reaches 50% is defined as the volume average particle diameter of the particles of the sample. Depending on the powder to be measured, 2 g of a measurement sample is added to 50 ml of an aqueous solution containing a surfactant as a dispersant (preferably a 5% aqueous solution of sodium alkylbenzenesulfonate), and an ultrasonic disperser (1,000 Hz) The sample dispersed for 2 minutes may be used as a measurement sample dispersion, and the volume average particle diameter may be measured by the same method as that for the sample dispersion.

The shape factor SF1 of the toner particles is desirably in the range of 100 to 140. Here, the shape factor (SF1) is obtained from the following equation.
SF1 = 100π × (ML) ² / (4 × A) (1)
Here, ML represents the maximum length of the toner particles. A represents the projected area of the toner particles.

  The shape factor of the toner particles is calculated as follows using the above formula (1). The image of the toner particles placed on the slide glass is measured with a microscope through a video camera, taken into an image analyzer (LUZEX III, manufactured by NIRECO), and the maximum toner length (ML) and projection area (A) are calculated. Then, these values are substituted into the above equation (1) to obtain the shape factor. The shape factor in the embodiment is an average shape factor, and is an average value of the shape factors calculated from the above formula (1) for arbitrary 100 toner particles.

  Hollow particles are used as an external additive externally added to the toner particles. The hollow particles include inorganic hollow particles and organic hollow particles. These hollow particles have one or two or more hollow portions therein.

  As the material of the inorganic hollow particles, known materials can be used. For example, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, silica sand, clay, Mica, wollastonite, diatomaceous earth, cerium chloride, bengara, chromium oxide, cerium oxide, antimony trioxide, magnesium oxide, zirconium oxide, silicon carbide, silicon nitride, calcium carbonate, magnesium carbonate, calcium phosphate, etc. can be used . It is more preferable to use silica or calcium carbonate because of its low specific gravity and low refractive index.

  As a method for producing inorganic hollow particles, a method of obtaining inorganic hollow particles by adding a treatment with a specific alcohol to a sol-gel method based on the Stover method, an alkyl silicate, etc., water, alcohol, acid amides, diol And at least one selected from semi-ethers of diols, a water-soluble polymer, a method prepared by hydrolysis and condensation in the presence of a catalyst, a metal oxide reacted with water and a base catalyst in an alcohol solvent to produce an alcogel A method of creating hollow airgel microspheres by injecting an inert gas into the droplets of the alcogel to form hollow alcogel microspheres and supercritically drying the alcogel, a polymer, Method obtained by hydrolysis and condensation in the presence of a catalyst, active inorganic oxides other than inorganic oxides Precipitated onto A material, then there is a method obtained by removing the core material.

  Moreover, you may surface-treat as needed. The surface treatment is not limited, and examples thereof include a treatment using a silane coupling agent, a titanate coupling agent, an aluminate coupling agent, various silicone oils, fatty acids, fatty acid metal salts, and the like. Particularly preferably, a silane coupling agent and various silicone oils can be used. The surface treatment amount is not limited, but is preferably 2.0% by mass to 30% by mass. If the amount is less than 2.0% by mass, the surface treatment effect cannot be obtained. If the amount is more than 30% by mass, aggregated particles are generated.

  The organic hollow particles are made of a resin, and various methods have been proposed for producing the organic hollow particles as described below. As a method for producing organic hollow particles, for example, a suspension in which a hydrophilic monomer, a crosslinkable monomer, and an oily substance coexist at a certain ratio are subjected to suspension polymerization or emulsion polymerization, whereby the oily substance is placed in the inner pores. A method of obtaining hollow polymer particles (organic hollow particles) by removing oily substances after obtaining polymer particles contained therein, a method of preparing a W / O / W emulsion and polymerizing monomers of the O layer 60-184004), a method of expanding a hollow core / shell particle having a swellable core at a temperature equal to or higher than the Tg of the shell layer (Japanese Patent Laid-Open No. 56-32513), a two-stage polymer having different solubility parameters A method by polymerization (JP-A-60-223873), a polymerizable monomer component containing a crosslinkable monomer and a hydrophilic monomer, and an oily substance are finely dispersed in water to form an O / W type emulsion. A method of polymerizing monomers to remove oily substances, a method of spraying or emulsifying liquid resin to form fine particles by suspension and heating and foaming, or a method of hollowing out in the wet process in the polymerization granulation process, etc. ing. The organic hollow particles used in the present invention may be produced by any method. By adjusting the combination and concentration of the emulsifiers used, the particle size and porosity of the particles can be adjusted.

  The crosslinking monomer of the constituent material of the organic hollow particles that can be used in the present invention is at least one polyfunctional monomer having at least two polymerizable double bonds (particularly divinylbenzene, divinylbiphenyl, divinylnaphthalene, diallylphthalate, At least one selected from the group consisting of triallyl cyanurate, ethylene glycol dimethacrylate and tetraethylene glycol dimethacrylate), and the monofunctional monomer is a monovinyl aromatic monomer, an acrylic monomer, a vinyl ester Those selected from the group consisting of monomers, vinyl ether monomers, monoolefin monomers, halogenated olefin monomers and diolefins are particularly preferred, but are not limited thereto.

  The hardness of the organic hollow particles is usually correlated with the degree of crosslinking, and can be expressed, for example, by the size of the gel fraction indicating the degree of crosslinking. The gel fraction means a gel fraction measured by the following method.

  A method for measuring the gel fraction will be described below. About 0.3 g of dried resin fine particles are weighed as a sample, put into 30 g of an organic solvent, and stirred for 60 minutes. Next, after centrifuging at a rotational speed of 10,000 rpm for 5 minutes, the supernatant liquid from which the lysate in the organic solvent has been extracted is removed. Next, after the undissolved material in the organic solvent is dried with a vacuum dryer, its mass is measured, and the gel fraction (% by mass) is calculated from the equation. The organic solvent may be any organic solvent that can dissolve the polymer composed of the monomer, and examples thereof include tetrahydrofuran.

  Gel fraction (% by mass) = (mass of monodispersed resin particle group not dissolved in organic solvent / mass of monodispersed resin particle group used for sample) × 100

  In the present invention, in order to obtain the required hardness for the organic hollow particles, the gel fraction needs to be 60% by mass or more. More preferably, it is 80 mass% or more. When the gel fraction is not 60% by mass or more, the organic hollow particles are deformed (collapsed) during various stresses received in the image forming apparatus and rubbing with the cleaning blade, making it difficult to form a toner dam. .

  The volume average particle diameter of the hollow particles (inorganic hollow particles and organic hollow particles) is preferably in the range of 100 nm to 10 μm. In particular, the volume average particle diameter of the hollow particles is preferably equal to or less than the volume average particle diameter of the toner particles. When the volume average particle size of the hollow particles is less than 100 nm, the particle size of the particles constituting the toner dam supplied to the cleaning blade is small. Therefore, an effective toner dam for preventing the passage of toner at the tip portion of the cleaning blade is provided. It cannot be formed. On the other hand, when the particle diameter of the hollow particles exceeds 10 μm, the hollow particles collapse at other sites (for example, the trimmer gap portion) before being supplied to the cleaning blade. As a result, hollow particles having a desired particle size distribution cannot be supplied to the cleaning blade, an effective toner dam cannot be formed, and the cleaning property cannot be improved.

  The porosity of the hollow particles is preferably 40% to 80%. The porosity (%) can be obtained by the following equation when m (m ≧ 1) hollow portions are present in the hollow particles.

ここで、Ｒは中空粒子の半径（中空粒子の粒径の１／２）であり、ｒ_ｎはｎ番目の中空粒子の中空部分の半径である。 [Equation 9]

Here, R is a hollow particle radius (1/2 of the particle diameter of hollow particles), r _n is the radius of the hollow portion of the n-th of the hollow particles.

  If the porosity exceeds 80%, the hollow particles tend to collapse due to stress in the developing machine, and it becomes difficult to stably supply the hollow particles to the cleaning blade portion. On the other hand, when the void ratio of the hollow particles is less than 40%, the hollow particles are not sufficiently collapsed by rubbing with the cleaning blade, and the toner dam is not sufficiently formed.

  The hollow particles are externally added to the toner particles as an external additive. Here, in the toner before development, that is, in the initial toner, the volume average particle diameter D50 of the hollow particles adhering to the toner is expressed as D50ini. It expresses. On the other hand, after the toner having the hollow particles is used for development and the toner image formed on the image carrier is transferred onto the transfer target, the toner remaining on the surface of the image carrier has a cleaning blade. Although it is removed in the cleaning process, the volume average particle diameter D50 of the hollow particles present at the tip of the cleaning blade is represented as D50dest. At the tip of the cleaning blade, the hollow particles adhering to the toner are released from the toner by an external force applied by the cleaning blade or the like (for example, stress received by rubbing with the cleaning blade). The hollow particles are destroyed by the external force.

  The particle size of the hollow particles after disintegration is smaller than the particle size of the hollow particles before development, and has a particle size distribution different from the initial state. Some of the hollow particles after collapsing are gathered and supplied to the tip portion 3 of the cleaning blade 2, and the gathered dam (toner dam 4 for blocking the toner between the cleaning blade 2 and the image carrier 1. ) (See FIG. 1). The toner dam 4 fills the gap between the cleaning blade 2 and the image carrier 1 and prevents toner remaining on the surface of the image carrier 1 from slipping between the cleaning blade 2 and the image carrier 1. The arrows in FIG. 1 indicate the direction in which the image carrier moves.

When the particle size distribution of the hollow particles after disintegration is grasped by the ratio (D50dest / D50ini) of the volume average particle diameter of the hollow particles before the development process and after the cleaning process, a toner having excellent cleaning properties can be obtained when the relationship shown below is satisfied. It turns out that it can be provided.
[Equation 10]
0.2 ≦ D50dest / D50ini ≦ 0.85

  When D50dest / D50ini <0.2, the particle size change of the external additive (hollow particles) at the cleaning blade portion is too large. Then, it is impossible to form a toner dam that can stably cope with various usage environments (low temperature and low humidity, normal temperature and normal humidity, and high temperature and high humidity) for a long time. When D50dest / D50ini> 0.85, the amount of external additive (hollow particles) supplied to the cleaning blade is insufficient, and a toner dam sufficient to improve the cleaning performance cannot be formed.

  The external addition amount of the hollow particles (inorganic hollow particles, organic hollow particles) to the toner particles is 0.5 parts by mass to 5 parts by mass, preferably 1 part by mass to 3 parts by mass with respect to 100 parts by mass of the toner particles. . If the amount is less than 0.5 parts by mass, the effect of improving the cleaning property of the spherical toner may not be sufficiently obtained. On the other hand, when the amount exceeds 5 parts by mass, when an external additive other than hollow particles is used, filming of the image carrier due to the external additive occurs, and image deterioration is likely to occur.

  As an external additive externally added to the toner particles, lubricant-containing particles are further used. The lubricant-containing particles include lubricant-containing inorganic particles and lubricant-containing organic particles. The lubricant-containing inorganic particles are those obtained by encapsulating a lubricant in the inorganic hollow particles, and the lubricant-containing organic particles are those obtained by encapsulating a lubricant in the organic hollow particles.

  As the lubricant encapsulated in the hollow particles (inorganic hollow particles and organic hollow particles), known lubricants conventionally used for toner external additives can be used. Examples of the lubricant include fatty acid metal salts such as aluminum stearate, calcium laurate, calcium myristate, calcium stearate, zinc claurate, zinc myristate, zinc stearate, magnesium stearate, silicone oil and wax. It can be mentioned, but is not limited to these.

  As a method for producing a lubricant-containing inorganic particle by encapsulating a lubricant in an inorganic hollow particle, for example, the hollow portion of the inorganic hollow particle is decompressed under reduced pressure to bring the pressurized liquid crystal into contact with the hollow A method in which a lubricant is soaked from micro holes on the wall surface using a pressure difference between inside and outside, a method in which a sol-gel reaction is performed in a lubricant-dispersed aqueous solution to produce lubricant-containing inorganic particles, and a dip or spray on lubricant fine particles There is a method of forming an oxide film by the method, and as a method of producing lubricant-containing organic particles, the lubricant is made into an emulsion and the lubricant is put into the W / O / W emulsion (in the case of resin particles) O layer. However, there is a method of encapsulating a lubricant in the process of producing the organic hollow particles, but it is not limited thereto.

  The amount of the lubricant contained in the hollow particles, that is, the content of the lubricant contained in the lubricant-containing particles may vary depending on the lubricant component, but is 0.02 to 5.0 with respect to the total mass of the toner particles. It is desirable to set the mass%. From the viewpoint of ease of seeping out of the lubricant, the content of the lubricant with respect to the hollow particles is preferably 1.0 to 30%. If it is less than 1.0%, the lubricant cannot be stably supplied to the image carrier. On the other hand, if it exceeds 30%, an excessive amount of lubricant is supplied to the image carrier.

  Moreover, you may surface-treat with respect to the said lubricant containing particle | grains as needed. Although the surface treatment is not limited, for example, the surface treatment disclosed as the surface treatment of the hollow particles may be performed.

  The volume average particle size of the lubricant-containing particles (lubricant-containing inorganic particles and lubricant-containing organic particles) is desirably in the range of 100 nm to 10 μm. In particular, the volume average particle size of the lubricant-containing particles is desirably not more than the volume average particle size of the toner particles. When the volume average particle size of the lubricant-containing particles is less than 100 nm, the particle size of the particles constituting the toner dam supplied to the cleaning blade is small, and therefore, it is effective for preventing the toner from passing through the tip portion of the cleaning blade. A toner dam cannot be formed. On the other hand, when the particle size of the lubricant-containing particles exceeds 10 μm, the lubricant-containing particles collapse at other sites (for example, the trimmer gap portion) before being supplied to the cleaning blade. Then, the lubricant-containing particles having a desired particle size distribution cannot be supplied to the cleaning blade, and an effective toner dam cannot be formed, and the cleaning property cannot be improved.

  The lubricant-containing particles are externally added to the toner particles as external additives. As in the case where the hollow particles are externally added, the toner adheres to the toner before development, that is, the toner in the initial state. The volume average particle diameter D50 of the hollow particles is represented as D50ini. Similarly to the case where the hollow particles are externally added, the volume average particle diameter D50 of the lubricant-containing particles present at the tip portion of the cleaning blade is represented as D50dest.

  In the case of using the lubricant-containing particles, as in the case of using the hollow particles, the particle size of the lubricant-containing particles after disintegration is smaller than the particle size of the lubricant-containing particles before development, Will have different particle size distributions. Some of the lubricant-containing particles after collapsing gather and are supplied to the tip portion 3 of the cleaning blade 2, and the gathering between the cleaning blade 2 and the image carrier 1 dam ( A toner dam 4) is formed (see FIG. 1). The toner dam 4 fills the gap between the cleaning blade 2 and the image carrier 1 and prevents toner remaining on the surface of the image carrier 1 from slipping between the cleaning blade 2 and the image carrier 1.

When the particle size distribution of the lubricant-containing particles after disintegration is grasped by the ratio (D50dest / D50ini) of the volume-average particle size of the lubricant-containing particles before the development process and after the cleaning process, the cleaning property is obtained when the following relationship is satisfied. It has been found that it is possible to provide an excellent toner.
[Equation 11]
0.2 ≦ D50dest / D50ini ≦ 0.85

  In the case of using the lubricant-containing particles, as in the case of using the hollow particles, when D50dest / D50ini <0.2, the particle size change of the external additive (lubricant-containing particles) at the cleaning blade portion is too large. Then, it is impossible to form a toner dam that can stably cope with various usage environments (low temperature and low humidity, normal temperature and normal humidity, and high temperature and high humidity) for a long time. When D50dest / D50ini> 0.85, the amount of external additive (lubricant-containing particles) supplied to the cleaning blade is insufficient, and a toner dam sufficient to improve the cleaning performance cannot be formed. .

  When the lubricant-containing particles are collapsed by an external force applied from a cleaning blade or the like, the lubricant appears from the particles and the lubricant is supplied to the cleaning blade. When the lubricant is supplied to the cleaning blade, the frictional force between the cleaning blade and the image carrier is reduced and wear of the cleaning blade and the image carrier is suppressed. When the wear is prevented, an unnecessary gap generated between the cleaning blade and the image carrier can be prevented, and the toner remaining on the image carrier can be effectively removed over a long period of time. Can be removed.

  The external addition amount of the lubricant-containing particles (lubricant-containing inorganic particles, lubricant-containing organic particles) to the toner particles is 0.5 parts by mass to 5 parts by mass, preferably 1 part by mass to 100 parts by mass of the toner. 3 parts by mass.

  Use of the above external additives (hollow particles, lubricant-containing particles) has the following effects. In conventional toners for improving fixability and low-temperature fixability, the wax existing in the toner particles or in the vicinity of the surface of the toner is stained on the toner surface by the pressure between the cleaning blade and the photoconductor. It often causes a defect (wax filming) that rubs and adheres to the surface of the photoconductor, and also contaminates the charging roller that contacts and charges the photoconductor. When particles are used, there is an effect of suppressing the above defects. It is presumed that most of the impact applied to the toner is absorbed when the external additive disintegrates.

  The inorganic hollow particles, the organic hollow particles, the lubricant-containing inorganic particles, and the lubricant-containing organic particles may be externally added to the toner particles alone, or two or more (for example, a combination of the two types may be inorganic. Grain empty particles and organic hollow particles, lubricant-containing inorganic particles and lubricant-containing organic particles, inorganic hollow particles and lubricant-containing inorganic particles, organic hollow particles and lubricant-containing organic particles, inorganic hollow particles and lubricant-containing organic particles, etc. May be used in combination.

  In addition to the external additives (hollow particles, lubricant-containing particles), one or more inorganic particles may be externally added to the toner particles as external additives. As the inorganic particles, known inorganic particles can be used. For example, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, silica sand, clay , Mica, wollastonite, diatomaceous earth, cerium chloride, bengara, chromium oxide, cerium oxide, antimony trioxide, magnesium oxide, zirconium oxide, silicon carbide, silicon nitride, calcium carbonate, magnesium carbonate, calcium phosphate, etc. . However, the inorganic particles are not limited to these.

  Moreover, you may surface-treat with respect to the said inorganic particle as needed. Although the surface treatment is not limited, for example, the surface treatment disclosed as the surface treatment of the hollow particles may be performed.

  As the inorganic particles, those having a volume average particle diameter in the range of 5 nm to 100 nm are used. For example, when two types of inorganic particles are used in combination, a combination of inorganic particles having a volume average particle size of 5 nm to 30 nm and inorganic particles having a volume average particle size of 40 nm to 100 nm is preferable. When toner particles are used in combination with the external additives (hollow particles, lubricant-containing particles) and inorganic particles (small external additives) having a volume average particle size of 5 nm to 30 nm, the cohesiveness of the toner can be suppressed. it can. When toner aggregation is suppressed, toner dams can be uniformly formed at the cleaning blade portion, so that it is easy to remove the toner remaining on the image carrier and the cleaning property is improved. Furthermore, when inorganic particles (medium external additive) having a volume average particle size of 40 nm to 100 nm that function as a spacer agent are combined with the small external additive, the small external additive functions as a spacer because the medium external additive functions as a spacer. It becomes difficult to embed the toner particles, and the cohesiveness of the toner can be suppressed more effectively, thereby improving the cleaning property.

  The added amount of the whole inorganic particles is 0.5 to 15 parts by mass, preferably 2 to 6 parts by mass with respect to 100 parts by mass of the toner particles.

  In particular, in the case of using a combination of inorganic particles (small external additive) having a volume average particle size of 5 nm to 100 nm and inorganic particles (medium external additive) having a volume average particle size of 40 nm to 100 nm, a small external additive is used. Is added in an amount of 0.5 to 5 parts by weight, preferably 1 to 3 parts by weight, with respect to 100 parts by weight of the toner particles. Is 0.5 to 5 parts by mass, preferably 1 to 3 parts by mass.

  Further, instead of the inorganic particles, known organic particles such as polystyrene particles, polymethyl methacrylate particles, and polyvinylidene fluoride particles may be used.

  When the toner for developing an electrostatic latent image of the present invention is used in a predetermined image forming apparatus, it is stable for a long period of time without degrading the image quality, and a good image carrier that does not depend on the operating temperature and humidity environment. Cleanability can be ensured.

  As a method of externally adding the above external additives (hollow particles, lubricant-containing particles, other external additives such as small external additives and medium external additives) to the toner particles and mixing them, for example, a V-type blender, A known method such as a Henschel mixer or a ready-mix mixer can be applied. The hollow particles and the lubricant-containing particles and other external additives may be mixed at the same time, or may be mixed together.

[Developer for electrostatic latent image development]
The developer of the present invention is a two-component developer in which a carrier is mixed with the electrostatic latent image developing toner.

  As the carrier, a resin-coated carrier having a resin coating layer in which a conductive material is dispersed and contained in a matrix resin on a core material is used.

  Matrix resins include polyethylene, polypropylene, polystyrene, polyacrylonitrile, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl chloride, polyvinyl carbazole, polyvinyl ether, polyvinyl ketone, vinyl chloride-vinyl acetate copolymer, styrene-acrylic acid copolymer. Examples include polymers, straight silicone resins composed of organosiloxane bonds or modified products thereof, fluororesins, polyesters, polyurethanes, polycarbonates, phenol resins, amino resins, melamine resins, benzoguanamine resins, urea resins, amide resins, epoxy resins, etc. However, it is not limited to these. Examples of the conductive material include metals such as gold, silver and copper, and titanium oxide, zinc oxide, barium sulfate, aluminum borate, potassium titanate, tin oxide, and carbon black. Is not to be done.

  The content of the conductive material is preferably 1 part by mass to 50 parts by mass and more preferably 3 parts by mass to 20 parts by mass with respect to 100 parts by mass of the matrix resin.

  Examples of the carrier core material include magnetic metals such as iron, nickel and cobalt, magnetic oxides such as ferrite and magnetite, and glass beads.

  The volume average particle diameter of the core material is generally 10 μm to 500 μm, preferably 30 μm to 100 μm.

  As a method for forming a resin coating layer on the surface of the carrier core material, a dipping method in which the carrier core material is immersed in a coating layer forming solution containing a matrix resin, a conductive material and a solvent, or a coating layer forming solution is used as the carrier. Spray method for spraying on the surface of the core material, fluidized bed method for spraying the coating layer forming solution in a state where the carrier core material is floated by flowing air, mixing the carrier core material and the coating layer forming solution in a kneader coater, A kneader coater method for removing the solvent may be mentioned.

  The solvent used in the coating layer forming solution is not particularly limited as long as it dissolves the matrix resin. For example, aromatic hydrocarbons such as toluene and xylene, and ketones such as acetone and methyl ethyl ketone. , Ethers such as tetrahydrofuran and dioxane can be used.

  The average film thickness of the resin coating layer is usually 0.1 to 10 μm, but in the present invention, it is preferably in the range of 0.5 to 3 μm in order to develop a stable volume resistivity of the carrier over time. .

The volume resistivity of the carrier formed as described above is 10 ⁶ to 10 ¹⁴ in the range of 10 ³ to 10 ⁴ V / cm corresponding to the upper and lower limits of a normal development contrast potential in order to achieve high image quality. It is preferably Ωcm. If the volume specific resistance of the carrier is less than 10 ⁶ Ωcm, the reproducibility of the thin line portion is poor, and toner fog is likely to occur on the background due to charge injection. Further, if the volume specific resistance of the carrier is larger than 10 ¹⁴ Ωcm, the reproduction of the black solid and halftone portions is deteriorated. In addition, the amount of carrier transferred to the photoreceptor increases, and the surface of the photoreceptor is easily damaged.

  In the present invention, the mixing ratio (mass ratio) of the toner and the carrier is preferably in the range of toner: carrier = 1: 100 to 30: 100, more preferably in the range of 3: 100 to 20: 100. It is.

  If the developer for developing an electrostatic latent image of the present invention is used in a predetermined image forming apparatus, a good image carrier cleaning property is ensured without deteriorating the image quality and regardless of the operating temperature and humidity environment. be able to.

(Image forming method)
The image forming method of the present invention comprises an image carrier, a latent image forming step for forming a latent image on the surface of the image carrier, and a latent image formed on the surface of the image carrier using the toner described above. A developing process for developing and forming a toner image, a transfer process for transferring the toner image formed on the surface of the image carrier to the transfer target, and a specific for removing residual toner on the surface of the image carrier after the transfer A cleaning step including a cleaning blade.

  The image forming method is a general electrophotographic image forming method having a cleaning step, wherein the specific cleaning blade is used in the cleaning step, and the toner containing the above-described external additive as a toner (this book Inventive electrostatic latent image developing toner).

  Any known intermediate transfer belt or intermediate transfer drum can be used. The collected residual toner is discarded after being put in a container or a collection box installed in the main body, or is recycled through an appropriate process.

  As an image forming apparatus to which the image forming method of the present invention is applied, for example, there is an image forming apparatus shown in FIG.

  The image forming apparatus 13 includes at least a charging unit 5 (step) for uniformly charging the image carrier 1 and an electrostatic latent image forming unit 6 for exposing the surface of the image carrier 1 to form an electrostatic latent image. Step), developing means 7 (step) for converting the electrostatic latent image into a toner image using a developer containing toner, transfer means 8 (step) for transferring the formed toner image onto the surface of the transfer target, transfer A cleaning unit 9 (step) for collecting the toner remaining on the surface of the image carrier 1 later by the cleaning blade 2 and a fixing unit 11 (step) for fixing the transferred toner image to the recording medium 10 are provided. The neutralization unit 12 (process) neutralizes the image carrier 1.

  Further, in the image forming apparatus 23 as shown in FIG. 3, the electrostatic latent image developing toner and developer of the present invention may be used. The image forming apparatus 23 includes an electrophotographic photosensitive member 1 (latent image carrier), a charger 5 (charging means) for charging the surface of the electrophotographic photosensitive member 1, and a power source for applying a voltage of the charger 5. 15, an image input device 6 (latent image forming means) for forming a latent image on the surface of the electrophotographic photosensitive member 1, and developing the latent image formed on the surface of the electrophotographic photosensitive member 1 with toner to form a toner image. A developing unit 7 (developing unit) to be obtained, a transfer unit 8 (transfer unit) for transferring the formed toner image onto the surface of the transfer material, and a cleaning unit for removing residual toner on the surface of the electrophotographic photosensitive member 1 by the cleaning blade 2. 9 (cleaning means), a lubricant supply device for assisting cleaning, a static eliminator 12 for removing the residual potential on the surface of the electrophotographic photosensitive member 1, and a toner image transferred to the surface of the transfer target 10 The heat and / or It has a fixing device 11 for fixing by pressure or the like, the.

  The lubricant supply device includes a solid lubricant 20, a lubricant support member (not shown) that supports the solid lubricant 20, a cleaning brush 21 for moving the lubricant 20 to the photoreceptor 1, and a cleaning brush. The flicker (not shown) for selecting the particle size of the solid lubricant 20 transferred above and for removing the toner transferred from the photoreceptor 1 is constituted.

  The cleaning brush 21 for applying the lubricant 20 rotates so as to contact the lower end of the solid lubricant 20, thereby scraping and holding the lubricant little by little from the lower end of the solid lubricant 20. Subsequently, the cleaning brush 21 after passing through the solid lubricant 20 rotates in contact with the flicker, whereby a relatively large lubricant among the lubricants scraped from the solid lubricant 20 is scraped off. Only the lubricant having a relatively small particle size is attached to the cleaning brush 21. At the same time, toner from the photosensitive member 1 attached to the cleaning brush 21 is simultaneously removed. Thus, a relatively small particle size and relatively small amount of lubricant scraped from the solid lubricant 20 by the cleaning brush 21 is applied to the surface of the image carrier 1 (photosensitive member). As the material of the cleaning brush 21, a known resin can be used, and examples thereof include resins such as polyester and acrylic resin.

  As the solid lubricant 20, for example, a dry solid hydrophobic lubricant is used, and typical examples thereof include zinc stearate, barium stearate, iron stearate, nickel stearate, cobalt stearate, copper stearate, stearin. Strontium acid, calcium stearate, cadmium stearate, magnesium stearate, zinc oleate, manganese oleate, iron oleate, cobalt oleate, lead oleate, magnesium oleate, copper oleate, palmitic acid, cobalt palmitate, partimine Copper acid, magnesium palmitate, aluminum palmitate, calcium palmitate, lead caprylate, lead caproate, zinc linolenate, cobalt linolenate, calcium linolenate and cadmium ricolinoleate Mention may be made of fatty acids such as arm. Natural waxes such as carbanau wax can also be used. These lubricants are solidified in a plate shape having a rectangular cross section. The length of the solid lubricant is set longer than the cleaning brush and the image area of the photoreceptor.

  Since the image forming apparatus 23 includes a lubricant supply device, the lubricant is supplied onto the surface of the image carrier, and the frictional force between the image carrier and the cleaning blade is reduced. If the electrostatic latent image developing toner and developer of the present invention are further used in the image forming apparatus, the lubricant can be more effectively supplied onto the surface of the cleaning blade and the image carrier. Therefore, the cleaning performance of the image forming apparatus can be stabilized for a long time.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto. In the description of the toner composition and the carrier, “part” means “part by mass” unless otherwise specified.

<D50dest / D50ini>
In the present invention, the external additive D50dest / D50ini is measured by taking 20 views of the surface of the toner particle magnified 30,000 times by FE-SEM (S-4700, manufactured by Hitachi, Ltd.), and using the enlarged photo. went. The volume average particle diameter (D50) of the external additive on the toner particles is obtained by measuring 10 particle diameters (total 200) of the external additives present on the toner particles on each enlarged photograph. Was used to write the particle size distribution, and its D50 was set to D50ini (D50 of the external additive of the toner before development was D50ini). Similarly, D50 of the external additive obtained by sampling the toner in the vicinity (tip portion) of the cleaning blade and measuring the same was defined as D50dest.

<Outer diameter (volume average particle diameter) / inner diameter measurement of hollow particles>
Dilute hollow particles with ethanol, dry it on a carbon grid for TEM, perform TEM observation, print the image, and arbitrarily extract 50 samples as primary particles. Circular particles corresponding to the image area The outer diameter (diameter) and inner diameter of the hollow particles were taken as the outer diameter and inner diameter of the hollow particles, respectively.

<Gel fraction measurement>
About 0.3 g of dried resin fine particles are weighed as a sample, put into 30 g of an organic solvent, and stirred for 60 minutes. Next, after centrifuging at a rotational speed of 10,000 rpm for 5 minutes, the supernatant liquid from which the lysate in the organic solvent has been extracted is removed. Next, after the undissolved material in the organic solvent is dried with a vacuum dryer, its mass is measured, and the gel fraction (% by mass) is calculated from the equation. The organic solvent may be any organic solvent that can dissolve the polymer composed of the monomer, and examples thereof include tetrahydrofuran.

<Measurement of outer diameter (volume average particle diameter) / inner diameter / lubricant content of lubricant-containing particles>
Dilute the lubricant-containing particles with ethanol, dry it on a TEM carbon grid, perform TEM observation, print the image, and arbitrarily extract 50 samples from the primary particles as a sample. The outer diameter (diameter) and inner diameter of the particles were taken as the outer diameter and inner diameter of the hollow particles, respectively. In addition, 1/2 of the major axis / minor axis of the lubricant-containing portion is considered as the radius of the lubricant-containing portion, and approximates to a circle as the lubricant occupation area, and the area occupied by the hollow particles (the outer diameter of the hollow particles is The area was calculated by approximating the circle as the radius and calculating the area. Content (%) = (Lubricant Occupied Area / Hollow Particle Area) × 100

<Toner particle shape factor>
In the present embodiment, the toner particle shape factor SF1 is obtained by using the above-described equation (1). As a specific method for obtaining the average shape factor, 20 views of the toner particle surface magnified 3500 times by FE-SEM (S-4700, manufactured by Hitachi, Ltd.) were taken, and the magnified photograph was taken as an image analyzer (LUZEX III). , Manufactured by Nireco Co., Ltd.), the equivalent circle diameter is measured, and the ML ² / A value of the above formula (1) is determined for each particle from the maximum length and area.

(A) Preparation of inorganic hollow particles (silica) 70 parts of 1% by weight aqueous ammonia solution in which 1.0 part of polyacrylic acid (molecular weight 450,000) was dissolved in a 500 ml glass round bottom flask equipped with a stirrer and a thermometer Next, 120 parts of ethanol and 150 parts of dimethylacetamide are sequentially added with stirring, and the temperature is maintained at 25 ° C. After these were sufficiently mixed, 16 parts of tetraethoxysilane was finally added and stirring was continued for 10 hours to complete the reaction. The reaction product liquid was dried at 200 ° C. to obtain a powder, and the powder was fired at 600 ° C. to obtain hollow particles. The volume average particle diameter (= outer diameter) of the hollow particles was 0.3 μm, the inner diameter was 0.23 μm, and the porosity was about 50%.

(B) Preparation of inorganic hollow particles (calcium carbonate) In a 2000 ml glass round bottom flask with a stirrer and a thermometer, in 300 ml of an aqueous calcium carbonate solution (2 mol / l as calcium carbonate), polyoxyethylene (n = 10) lauryl Add 100 ml of ether 2% ethyl acetate solution and stir at high speed to prepare an oil-in-water emulsion. Next, it is added to 2000 ml of polyoxyethylene lauryl ether 3% ethyl acetate solution and stirred at high speed to produce an oil-in-water oil-in-water emulsion. The oil-in-water emulsion in oil thus obtained is reacted by adding 500 ml of 1 mol / L ammonium sulfate and stirring. The reaction product liquid was dried at 200 ° C. to obtain a powder, and the powder was fired at 600 ° C. to obtain hollow particles. The volume average particle diameter (= outer diameter) of the hollow particles was 0.3 μm, the inner diameter (diameter of the hollow portion) was 0.16 μm (several hollow portions were confirmed), and the porosity was about 80%.

(C) Preparation of organic hollow particles Crosslinkable monomer and monofunctional monomer were added to 15 parts of an aqueous solution obtained by dissolving 0.05 parts of polyvinyl alcohol (polymerization degree 1700, saponification degree 88%) in water as a dispersion stabilizer. As a mixture, divinylbiphenyl 51.7% by mass, ethylvinylbiphenyl 23.6% by mass, methylvinylbiphenyl 6.2% by mass, vinylbiphenyl 5.8% by mass and other non-polymerizable components (diethylbiphenyl, ethylbiphenyl) Etc.) A solution obtained by uniformly mixing 0.25 parts of a mixture composed of 12.7% by mass, 0.005 parts of benzoyl peroxide as an initiator, and 0.25 parts of hexadecane as a solvent was suspended. The suspension was carried out using a homogenizer as an apparatus under stirring conditions of 5000 rpm and room temperature. The obtained suspension droplets had an average particle size of about 2 μm. Subsequently, the suspension was heated at 70 ° C. with stirring under a nitrogen gas atmosphere, and suspension polymerization was performed for 24 hours. The dispersion obtained above was filtered using a filter paper, and the hollow polymer fine particles were isolated and dried under conditions of a temperature of about 70 ° C. and an atmospheric pressure to obtain organic hollow particles. The volume average particle diameter (= outer diameter) of the hollow particles was 2 μm, the inner diameter was 1.6 μm, and the porosity was about 50%.

(D) Preparation of organic hollow particles Crosslinkable monomer and monofunctional monomer were added to 15 parts of an aqueous solution obtained by dissolving 0.05 parts of polyvinyl alcohol (polymerization degree 1700, saponification degree 88%) in water as a dispersion stabilizer. As a mixture, divinylbiphenyl 41.4% by weight, ethyl vinylbiphenyl 18.9% by weight, methylvinylbiphenyl 4.96% by weight, vinylbiphenyl 4.64% by weight and other non-polymerizable components (diethylbiphenyl, ethylbiphenyl) Etc.) A solution obtained by uniformly mixing 0.25 parts of a mixture composed of 12.7% by mass, 0.005 parts of benzoyl peroxide as an initiator, and 0.25 parts of hexadecane as a solvent was suspended. The suspension was carried out using a homogenizer as an apparatus under stirring conditions of 5000 rpm and room temperature. The obtained suspension droplets had a volume average particle diameter of about 2 μm. Next, the suspension was heated at 70 ° C. with stirring under a nitrogen gas atmosphere and subjected to suspension polymerization for 20 hours. The dispersion obtained above was filtered using a filter paper, and the hollow polymer fine particles were isolated and dried under conditions of a temperature of about 70 ° C. and an atmospheric pressure to obtain organic hollow particles. The hollow particles had a volume average particle diameter (= outer diameter) of 4 μm, an inner diameter of 3.7 μm, and a porosity of about 80%.

(E) Preparation of lubricant-containing inorganic particles (lubricant-containing silica) 10% by weight zinc stearate dispersion in an aqueous sodium silicate solution obtained by diluting 300 parts of silicic acid (SiO ₂ concentration 29% by weight) with 90 parts of pure water 100 parts of a liquid (sodium dodecylbenzenesulfonate 0.5 pph as a dispersant) was added and stirred at high speed to prepare a dispersion. This dispersion was put into a solution obtained by dissolving 4 parts of sorbitan monooleate in 960 ml of trichlorotrifluoroethane, and emulsified with a homomixer to obtain a W / O type emulsion. This emulsion was neutralized with an acid to gel the silica component. The slurry after separation of trichlorotrifluoroethane was filtered, and the cake was washed with solids and dried. The reaction product liquid was dried at 120 ° C. to obtain a powder, and the powder was fired at 150 ° C. to obtain lubricant-containing inorganic particles. The volume average particle diameter (= outer diameter) of this particle was 0.1 μm, the inner diameter was 0.07 μm, the porosity was about 50%, and the lubricant content was about 40%.

(F) Preparation of Lubricant-Containing Inorganic Particles (Lubricant-Containing Calcium Carbonate) In a 2000 ml glass round bottom flask equipped with a stirrer and a thermometer, 300 ml of an aqueous calcium carbonate solution (2 mol / l as calcium carbonate) was added to polyoxyethylene ( n = 10) 100 ml of 2% ethyl acetate solution of lauryl ether was added and stirred at high speed to prepare an oil-in-water emulsion. Subsequently, it added to 2000 ml of polyoxyethylene lauryl ether 3% ethyl acetate solution, and stirred at high speed to prepare an oil-in-water oil-in-water emulsion. The oil-in-water emulsion in oil thus obtained was reacted by adding 500 ml of 1 mol / L ammonium sulfate and stirring. The reaction product liquid was dried at 200 ° C. to obtain a powder, and the powder was fired at 600 ° C. to obtain hollow particles. The volume average particle diameter (= outer diameter) of the hollow particles was 0.1 μm, the inner diameter was 0.09 μm, and the porosity was about 80%. 20 parts of this hollow calcium carbonate was impregnated with 50 parts of zinc stearate heated to 200 ° C. and heated and melted all day and night. The reaction product solution filtered was dried at 120 ° C. to obtain a powder, and the powder was fired at 150 ° C. to obtain lubricant-containing inorganic particles. The volume average particle diameter (= outer diameter) of the hollow particles was 0.2 μm, the inner diameter was 0.19 μm, and the porosity was about 80%.

(G) Preparation of Lubricant-Containing Organic Particles As a dispersion stabilizer, 15 parts of an aqueous solution obtained by dissolving 0.05 parts of polyvinyl alcohol (polymerization degree 1700, saponification degree 88%) in water is mixed with a crosslinkable monomer and monofunctional. As a mixture with a polymerizable monomer, 41.4% by weight of divinyl biphenyl, 18.9% by weight of ethyl vinyl biphenyl, 5.0% by weight of methyl vinyl biphenyl, 4.6% by weight of vinyl biphenyl and other non-polymerizable components (diethyl biphenyl, Ethyl biphenyl, etc.) 0.2 parts of a mixture consisting of 10.2% by weight, 25 parts by weight of zinc stearate dispersion (sodium dodecylbenzenesulfonate 2.5 pph) 0.05 parts, benzoyl peroxide 0.005 parts as initiator Then, a solution obtained by uniformly mixing 0.25 part of hexadecane as a solvent was suspended. The suspension was carried out using a homogenizer as an apparatus under stirring conditions of 5000 rpm and room temperature. The obtained suspension droplets had an average particle size of about 2 μm. Subsequently, the suspension was heated at 70 ° C. with stirring under a nitrogen gas atmosphere, and suspension polymerization was performed for 24 hours. The dispersion obtained above was filtered using a filter paper, the hollow polymer fine particles were isolated, and dried under conditions of a temperature of about 70 ° C. and atmospheric pressure, whereby lubricant-containing organic particles were obtained. . The volume average particle diameter (= outer diameter) of these particles was 2 μm, the inner diameter was 1.47 μm, the porosity was about 50%, and the lubricant content was about 40%.

(H) Preparation of Lubricant-Containing Organic Particles As a dispersion stabilizer, 15 parts of an aqueous solution obtained by dissolving 0.05 parts of polyvinyl alcohol (polymerization degree 1700, saponification degree 88%) in water is mixed with a crosslinkable monomer and monofunctional. As a mixture with a polymerizable monomer, 41.4% by weight of divinyl biphenyl, 18.9% by weight of ethyl vinyl biphenyl, 4.96% by weight of methyl vinyl biphenyl, 4.64% by weight of vinyl biphenyl and other non-polymerizable components (diethyl biphenyl, 0.25 parts of a mixture comprising 12.7% by weight of ethyl biphenyl, etc., 0.07 parts of 25% by weight zinc stearate dispersion (sodium dodecylbenzenesulfonate 2.5 pph), 0.005 parts of benzoyl peroxide as an initiator Then, a solution obtained by uniformly mixing 0.25 part of hexadecane as a solvent was suspended. The suspension was carried out using a homogenizer as an apparatus under stirring conditions of 5000 rpm and room temperature. The obtained suspension droplets had an average particle size of about 2 μm. Next, the suspension was heated at 70 ° C. with stirring under a nitrogen gas atmosphere and subjected to suspension polymerization for 20 hours. The dispersion liquid obtained above was filtered using a filter paper, the particles were isolated, and dried under conditions of a temperature of about 70 ° C. and atmospheric pressure, whereby lubricant-containing organic particles were obtained. The volume average particle diameter (= outer diameter) of the particles was 2 μm, the inner diameter was 1.78 μm, the porosity was about 80%, and the lubricant content was 70%.

(I) Preparation of inorganic hollow particles (silica) 70 parts of 1 mass% aqueous ammonia solution in which 1.0 part of polyacrylic acid (molecular weight 450,000) was dissolved in a 500 ml glass round bottom flask equipped with a stirrer and a thermometer Next, 120 parts of ethanol and 150 parts of dimethylacetamide were sequentially added with stirring, and the temperature was maintained at 25 ° C. After these were sufficiently mixed, 16 parts of tetraethoxysilane was finally added and stirring was continued for 10 hours to complete the reaction. A powder obtained by drying the reaction product solution at 200 ° C. was obtained, and the powder was fired at 600 ° C. to obtain hollow particles. The volume average particle diameter (= outer diameter) of the hollow particles was 0.3 μm, the inner diameter (diameter of the hollow portion) was 0.2 μm (several hollow portions were confirmed), and the porosity was about 90%.

(J) Preparation of Lubricant-Containing Organic Particles As a dispersion stabilizer, 15 parts of an aqueous solution obtained by dissolving 0.05 parts of polyvinyl alcohol (polymerization degree 1700, saponification degree 88%) in water is mixed with a crosslinkable monomer and monofunctional. As a mixture with a base monomer, divinylbiphenyl 41.4% by mass, ethylvinylbiphenyl 18.9% by mass, methylvinylbiphenyl 4.96% by mass, vinylbiphenyl 4.64% by mass and other non-polymerizable components (diethylbiphenyl, 0.25 parts of a mixture comprising 12.7% by weight of ethyl biphenyl, etc., 0.07 parts of 25% by weight zinc stearate dispersion (sodium dodecylbenzenesulfonate 2.5 pph), 0.005 parts of benzoyl peroxide as an initiator Then, a solution obtained by uniformly mixing 0.25 part of hexadecane as a solvent was suspended. The suspension was performed using a homogenizer as an apparatus and stirring speed of 5000 rpm at room temperature. The obtained suspension droplets had a volume average particle diameter of about 2 μm. Next, the suspension was heated at 70 ° C. with stirring under a nitrogen gas atmosphere and subjected to suspension polymerization for 20 hours. The dispersion liquid obtained as described above was filtered using a filter paper, the particles were isolated, and dried under conditions of a temperature of about 70 ° C. and atmospheric pressure, whereby lubricant-containing organic particles were obtained. The volume average particle diameter (= outer diameter) of the particles was 2 μm, the inner diameter was 1.3 μm (several were observed), the porosity was about 90%, and the lubricant content was 70%.

[Colored particle production method]
<Preparation of resin dispersion (1)>
Styrene 370 parts n-Butyl acrylate 30 parts Acrylic acid 8 parts Dodecanethiol 24 parts Carbon tetrabromide 4 parts or more mixed and dissolved in a nonionic surfactant (Nonipol 400: Sanyo Chemical Co., Ltd.) 6 parts) and anionic surfactant (Neogen SC: manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) 10 parts were dissolved in 550 parts of ion-exchanged water and emulsified and dispersed in a flask. To this, 50 parts of ion-exchanged water in which 4 parts of ammonium persulfate was dissolved was added. After carrying out nitrogen substitution, the inside of the flask was stirred and heated in an oil bath until the contents reached 70 ° C., and emulsion polymerization was continued for 5 hours. As a result, a resin dispersion (1) in which resin particles having a volume average particle diameter of 155 nm, Tg = 59 ° C., and weight average molecular weight Mw = 12000 was dispersed was obtained.

<Preparation of resin dispersion (2)>
Styrene 280 parts n-Butyl acrylate 120 parts Acrylic acid 8 parts or more mixed and dissolved in 6 parts of nonionic surfactant (Nonipol 400: Sanyo Kasei Co., Ltd.) and anionic surfactant (Neogen SC: manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) 12 parts dissolved in ion-exchanged water 550 parts emulsified and dispersed in a flask, and slowly mixed for 10 minutes while dissolving 3 parts ammonium persulfate in this ion 50 parts of exchange water was added. After carrying out nitrogen substitution, the inside of the flask was stirred and heated in an oil bath until the contents reached 70 ° C., and emulsion polymerization was continued for 5 hours. As a result, a resin dispersion liquid (2) in which resin particles having a volume average particle diameter of 105 nm, Tg = 53 ° C., and weight average molecular weight Mw = 550000 was dispersed was obtained.

<Preparation of colored dispersion (1)>
50 parts of carbon black (Mogal L: manufactured by Cabot)
Nonionic surfactant 5 parts (Nonipol 400: manufactured by Sanyo Chemical Co., Ltd.)
Ion-exchanged water 200 parts or more of components are mixed, dissolved, and dispersed for 10 minutes using a homogenizer (Ultra Turrax T50: manufactured by IKA). Colorant (carbon black) particles having a volume average particle size of 250 nm A dispersed colored dispersant (1) was prepared.

<Preparation of colored dispersion (2)>
Cyan pigment B15 370 parts Nonionic surfactant 5 parts (Nonipol 400: manufactured by Sanyo Chemical Co., Ltd.)
Ion exchange water 200 parts or more of components are mixed, dissolved, and dispersed for 10 minutes using a homogenizer (Ultra Turrax T50: manufactured by IKA). Colorant (Cyan pigment) particles having a volume average particle diameter of 250 nm are obtained. A dispersed colored dispersant (2) was prepared.

<Preparation of colored dispersion (3)>
Magenta pigment R122 70 parts Nonionic surfactant 5 parts (Nonipol 400: manufactured by Sanyo Chemical Co., Ltd.)
Ion-exchanged water 200 parts or more of components are mixed, dissolved, and dispersed for 10 minutes using a homogenizer (Ultra Turrax T50: manufactured by IKA). Colorant (Magenta pigment) particles having a volume average particle size of 250 nm A dispersed colored dispersant (3) was prepared.

<Preparation of colored dispersion (4)>
Yellow pigment Y180 100 parts Nonionic surfactant 5 parts (Nonipol 400: manufactured by Sanyo Chemical Co., Ltd.)
Ion-exchanged water 200 parts or more of components are mixed, dissolved, and dispersed for 10 minutes using a homogenizer (Ultra Turrax T50: manufactured by IKA). Colorant (Yellow pigment) particles having a volume average particle diameter of 250 nm are obtained. A dispersed colored dispersant (4) was prepared.

<Releasing agent dispersion (1)>
50 parts of paraffin wax (HNP0190: manufactured by Nippon Seiwa Co., Ltd., melting point 85 ° C.)
5 parts of cationic surfactant (Sanisol B50: manufactured by Kao Corporation)
The above components were dispersed in a round stainless steel flask using a homogenizer (Ultra Turrax T50: manufactured by IKA) for 10 minutes, and then dispersed with a pressure discharge homogenizer, and the volume average particle diameter was 550 nm. A release agent dispersion liquid (1) in which release agent particles are dispersed was prepared.

<Preparation of aggregated particles>
Resin dispersion (1) 120 parts Resin dispersion (2) 80 parts Colorant dispersion (1) 200 parts Mold release dispersion (1) 40 parts Cationic surfactant 1.5 parts (Sanisol B50: Kao Corporation ) Made)
The above components were mixed and dispersed in a round stainless steel flask using a homogenizer (Ultra Turrax T50: manufactured by IKA), and then heated to 50 ° C. while stirring the inside of the flask in an oil bath for heating. . After maintaining at 45 ° C. for 20 minutes, it was confirmed with an optical microscope that it was confirmed that aggregated particles having a volume average particle diameter of about 4.3 μm were formed. Further, 60 parts of the resin dispersion (1) as a resin-containing fine particle dispersion was gently added to the dispersion. The temperature of the heating oil bath was raised to 50 ° C. and held for 30 minutes. When observed with an optical microscope, it was confirmed that adhered particles having a volume average particle diameter of about 5.3 μm were formed.

<Creation of colored particles>
After adding 3 parts of an anionic surfactant (Neogen SC: manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) to the particle dispersion, the inside of the stainless steel flask is sealed, and stirred up to 105 ° C. using a magnetic seal. Heated and held for 4 hours. And after cooling, the reaction product was filtered, washed sufficiently with ion-exchanged water, and then dried to obtain colored particles.

<Generation of colored particles Kuro>
Using the colorant dispersion (1), Kuro toner having SF1 = 18.5 and volume average particle diameter D50 = 5.8 μm was obtained by the above-described method.

<Generation of colored particles Cyan>
By using the colorant dispersion (2), a cyan toner having SF1 = 130 and volume average particle diameter D50 = 5.6 μm was obtained by the above method.

<Generation of colored particles Magenta>
Using the colorant dispersion (3), a Magenta toner having SF1 = 132.5 and a volume average particle diameter D50 = 5.5 μm was obtained by the above method.

<Generation of colored particles Yellow>
Using the colorant dispersion (4), a yellow toner having SF1 = 127 and volume average particle diameter D50 = 5.9 μm was obtained by the above method.

<Generation of carrier>
Ferrite particles (volume average particle size: 50 μm) 100 parts Toluene 14 parts Styrene-methyl methacrylate copolymer (component ratio: 90/10, Mw 80,000)
2 parts Carbon black (R330: manufactured by Cabot Corporation) 0.2 parts First, the above components except for ferrite particles are stirred with a stirrer for 10 minutes to prepare a dispersed coating solution, and then the coating solution and ferrite particles are mixed. After putting in a vacuum degassing type kneader and stirring at 60 ° C. for 30 minutes, the carrier was obtained by further degassing by heating under reduced pressure and drying. This carrier had a volume resistivity of 10 ¹¹ Ωcm at an applied electric field of 1000 V / cm.

Example 1
100 parts of each of the above colored particles Kuro, Cyan, Magenta and Yellow toner, 3 parts of hollow particles (A) and 1.2 parts of hydrophobic titanium oxide (T805, manufactured by Nippon Aerosil Co., Ltd.) having a volume average particle size of 21 nm are Henschel mixers. Was used for 10 minutes at a peripheral speed of 32 m / s, and then coarse particles were removed using a 45 μm mesh sieve to obtain a toner. 100 parts of the carrier and 5 parts of the toner were stirred at 40 rpm for 20 minutes using a V-blender, and sieved with a sieve having a 177 μm mesh to obtain a developer. Using a modified Docucolor 1250 manufactured by Fuji Xerox, the developer of the above four colors was introduced into the developing machine, and the cleaning property was evaluated. The evaluation of the cleaning property was judged by the streak-like image quality defect on the print and the toner contamination of the charging roll. Run 10,000 sheets in full color mode under low temperature and low humidity (10 ° C, 15% RH), medium temperature and medium humidity (23 ° C, 55% RH) and high temperature and high humidity (28 ° C, 85% RH) Although the test was conducted, no problem in image quality occurred under any of the environmental conditions. Also, the contamination of the charging roll was not confirmed and was good (D50ini (Yellow) = 0.18 μm, D50dest (Yellow) = 0.13 μm, D50dest (Yellow) / D50ini (Yellow) = 0.70, D50ini (Magenta) = 0.19 μm, D50dest (Magenta) = 0.14μm, D50dest (Magenta) / D50ini (Magenta) = 0.75, D50ini (Cyan) = 0.18μm, D50dest (Cyan) = 0.15μm, D50dest (Cyan) / D50ini (Cyan) = 0.85, D50ini (Kuro) = 0.18 μm, D50dest (Kuro) = 014 μm, D50dest (Kuro) / D50ini (Kuro) = 0.80).

[Example 2]
After blending 100 parts of the cyan toner of the above colored particles with 3 parts of the above hollow particles (B) as an external additive at a peripheral speed of 32 m / s for 10 minutes using a Henschel mixer, hydrophobic silica having a volume average particle diameter of 12 nm ( RY200 (manufactured by Nippon Aerosil Co., Ltd.) was added in an amount of 1.1 parts, blended at a peripheral speed of 20 m / s for 5 minutes, and coarse particles were removed using a 45 μm mesh sieve to obtain an electrostatic latent image developing toner. 100 parts of the carrier and 5 parts of the toner were stirred at 40 rpm for 20 minutes using a V-blender, and sieved with a sieve having a 177 μm mesh to obtain a developer. The obtained developer was put into the same remodeling machine as in Example 1, and the cleaning property was evaluated under the same conditions as in Example 1. As a result, no problem in image quality occurred in any environmental condition, and no contamination of the charging roll was confirmed, which was good (D50ini (Cyan) = 0.2 μm, D50dest (Cyan) = 0.14 μm, D50dest (Cyan) / D50ini (Cyan) = 0.70).

[ Reference Example 1 ]
After blending 10 parts of Cyan toner of the above colored particles with 3 parts of the above hollow particles (C) as an external additive for 10 minutes at a peripheral speed of 32 m / s with a Henschel mixer, hydrophobic titanium oxide having a volume average particle diameter of 21 nm 1 part of T805 (manufactured by Nippon Aerosil Co., Ltd.) and 1 part of hydrophobic silica (RX50, manufactured by Nippon Aerosil Co., Ltd.) with an average particle size of 40 nm are added, blended at a peripheral speed of 20 m / s for 5 minutes, and a 45 μm mesh sieve is used. Coarse particles were removed to obtain a toner for developing an electrostatic latent image. 100 parts of the carrier and 5 parts of the toner were stirred at 40 rpm for 20 minutes using a V-blender, and sieved with a sieve having a 177 μm mesh to obtain a developer. The obtained developer was put into the same remodeling machine as in Example 1, and the cleaning property was evaluated under the same conditions as in Example 1. As a result, there was no problem in image quality in any environmental condition, and no contamination of the charging roll was confirmed, which was good (D50ini (Cyan) = 1.9 μm, D50dest (Cyan) = 0.4 μm, D50dest (Cyan) / D50ini (Cyan) = 0.2).

[ Reference Example 2 ]
After blending 100 parts of the cyan toner of the colored particles with 3 parts of the hollow particles (D) as an external additive at a peripheral speed of 32 m / s for 10 minutes using a Henschel mixer, hydrophobic silica having a volume average particle diameter of 12 nm ( 1 part of RY200 (manufactured by Nippon Aerosil Co., Ltd.) and 1 part of hydrophobic silica (RX50, manufactured by Nippon Aerosil Co., Ltd.) with a volume average particle size of 40 nm are blended for 5 minutes at a peripheral speed of 20 m / s, and a sieve with a 45 μm mesh is used. Coarse particles were removed to obtain a toner for developing an electrostatic latent image. 100 parts of the carrier and 5 parts of the toner were stirred at 40 rpm for 20 minutes using a V-blender, and sieved with a sieve having a 177 μm mesh to obtain a developer. The obtained developer was put into the same remodeling machine as in Example 1, and the cleaning property was evaluated under the same conditions as in Example 1. As a result, no problem in image quality occurred in any of the environmental conditions, and no contamination of the charging roll was confirmed, which was good (D50ini (Cyan) = 3.9 μm, D50dest (Cyan) = 2.7 μm, D50dest (Cyan) / D50ini (Cyan) = 0.70).

[Comparative Example 1]
One part of hydrophobic titanium oxide (T805, manufactured by Nippon Aerosil Co., Ltd.) having a volume average particle diameter of 21 nm is added as an external additive to 100 parts of the cyan toner of the above colored particles, blended for 5 minutes at a peripheral speed of 20 m / s, and 45 μm. Coarse particles were removed using a mesh sieve to obtain a toner for developing an electrostatic latent image. 100 parts of the carrier and 5 parts of the toner were stirred at 40 rpm for 20 minutes using a V-blender, and sieved with a sieve having a 177 μm mesh to obtain a developer. The obtained developer was put into the same remodeling machine as in Example 1, and the cleaning property was evaluated under the same conditions as in Example 1. As a result, in the low-temperature and low-humidity environment, cleaning failure occurred from the first sheet. Further, the charging roll was very dirty, and image quality deterioration due to uneven charging occurred remarkably. Even at room temperature and humidity and high temperature and high humidity environment, although not as low temperature and low humidity environment, cleaning failure occurred in the middle, dirt on the charging roll was also observed, and image quality deterioration due to uneven charging occurred significantly (D50ini (Cyan) = 0.02 μm, D50dest (Cyan) = 0.02 μm, D50dest (Cyan) / D50ini (Cyan) = 1.00).

[Comparative Example 2]
To 100 parts of the cyan toner of the above colored particles, 3 parts of hydrophobic silica having a volume average particle diameter of 100 nm and 1 part of hydrophobic titanium oxide having a volume average particle diameter of 21 nm (T805, manufactured by Nippon Aerosil Co., Ltd.) are added as external additives. Then, blending was carried out at a peripheral speed of 20 m / s for 5 minutes, and coarse particles were removed using a sieve having a mesh of 45 μm to obtain an electrostatic latent image developing toner. 100 parts of the carrier and 5 parts of the toner were stirred at 40 rpm for 20 minutes using a V-blender, and sieved with a sieve having a 177 μm mesh to obtain a developer. The obtained developer was put into the same remodeling machine as in Example 1, and the cleaning property was evaluated under the same conditions as in Example 1. As a result, in a low-temperature and low-humidity environment, cleaning failure occurred with 500 sheets. Further, the charging roll was very dirty, and image quality deterioration due to uneven charging occurred remarkably. Even at room temperature and humidity and high temperature and high humidity environment, although not as low temperature and low humidity environment, cleaning failure occurred in the middle, dirt on the charging roll was also observed, and image quality deterioration due to uneven charging occurred significantly (D50ini (Cyan) = 0.3 μm, D50dest (Cyan) = 0.3 μm, D50dest (Cyan) / D50ini (Cyan) = 1.00).

[Comparative Example 3]
To 100 parts of the cyan toner of the above colored particles, 3 parts of silicone resin fine particles having a volume average particle diameter of 2 μm and 1 part of hydrophobic silica having a volume average particle diameter of 12 nm (RY200, manufactured by Nippon Aerosil Co., Ltd.) as an external additive Add 1 part of hydrophobic silica (RX50, manufactured by Nippon Aerosil Co., Ltd.) with an average particle size of 40 nm, blend for 5 minutes at a peripheral speed of 20 m / s, remove coarse particles using a 45 μm mesh sieve, and develop an electrostatic latent image Toner was obtained. 100 parts of the carrier and 5 parts of the toner were stirred at 40 rpm for 20 minutes using a V-blender, and sieved with a sieve having a 177 μm mesh to obtain a developer. The obtained developer was put into the same remodeling machine as in Example 1, and the cleaning property was evaluated under the same conditions as in Example 1. As a result, in a low-temperature and low-humidity environment, cleaning failure occurred with 500 sheets. Further, the charging roll was very dirty, and image quality deterioration due to uneven charging occurred remarkably. Even at room temperature and humidity and high temperature and high humidity environment, although not as low temperature and low humidity environment, cleaning failure occurred in the middle, dirt on the charging roll was also observed, and image quality deterioration due to uneven charging occurred significantly (D50ini (Cyan) = 0.2 μm, D50dest (Cyan) = 0.2 μm, D50dest (Cyan) / D50ini (Cyan) = 1.00).

[Comparative Example 4]
100 parts of the cyan toner of the above colored particles, 3 parts of inorganic hollow particles (I) as an external additive, 1 part of hydrophobic silica (RY200, manufactured by Nippon Aerosil Co., Ltd.) having a volume average particle diameter of 12 nm, and volume average particle diameter Add 1 part of 40 nm hydrophobic silica (RX50, manufactured by Nippon Aerosil Co., Ltd.), blend for 5 minutes at a peripheral speed of 20 m / s, remove coarse particles using a 45 μm mesh sieve, and use toner for electrostatic latent image development. Obtained. 100 parts of the carrier and 5 parts of the toner were stirred at 40 rpm for 20 minutes using a V-blender, and sieved with a sieve having a 177 μm mesh to obtain a developer. The obtained developer was put into the same remodeling machine as in Example 1, and the cleaning property was evaluated under the same conditions as in Example 1. As a result, in a low-temperature and low-humidity environment, cleaning failure occurred with 500 sheets. At that time, the photosensitive member and the charging roll were very dirty, and the image quality deteriorated remarkably. Even in normal temperature and high humidity environments, although not as low as low temperature and low humidity environments, cleaning defects occurred in the middle, as well as contamination of photoconductors and charging rolls, and image quality degradation was noticeable (D50ini ( Cyan) = 0.2 μm, D50dest (Cyan) = 0.04 μm, D50dest (Cyan) / D50ini (Cyan) = 0.18).

The results in the above Examples and Comparative Examples are summarized in Table 1 below. The left column of the results shown in Table 1 below is the number of sheets until a cleaning failure occurs, and the right column is the cleaning performance evaluation result obtained from the numerical values in the left column according to the evaluation criteria shown below.
○: No problem up to 10,000 sheets Δ: Cleaning failure occurred at 5000 to 10000 sheets ×: Cleaning failure occurred at 1000 to 5000 sheets xx: Cleaning failure occurred at 1 to 1000 sheets

  When a toner having hollow particles on the surface was used, good cleaning properties could be obtained regardless of the environment. On the other hand, it is difficult for the developer of the toner having no hollow particles to show good cleaning characteristics regardless of the environment, as in the results of Comparative Examples except Comparative Example 3.

  In each developer evaluation, the photoreceptor was taken out after copying 10,000 sheets and the surface was observed. The scratches and contamination were slight. On the other hand, when the developer containing no hollow particles of the present invention is used, when the developers of Comparative Examples 1, 2, 3, and 4 are used, the photoreceptor is extracted after copying 10,000 sheets, and surface observation is performed. As a result, it was confirmed that the scratches were clear. The photoreceptor of Comparative Example 4 showed significant toner adhesion.

[Example 3 ]
100 parts of Cyan toner of the above colored particles, 3 parts of lubricant-containing hollow particles (E), 1.2 parts of hydrophobic titanium oxide having a volume average particle diameter of 21 nm (T805, manufactured by Nippon Aerosil Co., Ltd.) and a peripheral speed using a Henschel mixer After blending at 32 m / s for 10 minutes, coarse particles were removed using a sieve of 45 μm mesh to obtain a toner. 100 parts of the carrier and 5 parts of the toner were stirred at 40 rpm for 20 minutes using a V-blender, and sieved with a sieve having a 177 μm mesh to obtain a developer. Using a modified Docucolor 1250 manufactured by Fuji Xerox, the developer was introduced into the developing machine, and the cleaning property was evaluated. The evaluation of the cleaning property was judged by the streak-like image quality defect on the print and the toner contamination of the charging roll. Low temperature and low humidity (10 ℃, RH 15%) , moisture in the medium-temperature (23 ℃, 55% RH) performed based on 50,000 sheets running test of the respective environmental conditions of high temperature and high humidity (28 ℃, RH 85%) However, there was no problem in image quality under any environmental conditions. Further, no contamination of the charging roll was confirmed, and it was good (D50ini (Cyan) = 3.8 μm, D50dest (Cyan) = 3.1 μm, D50dest (Cyan) / D50ini (Cyan) = 0.8).

[Example 4 ]
After blending 100 parts of the cyan toner of the above colored particles with 3 parts of the lubricant-containing hollow particles (F) as an external additive at a peripheral speed of 32 m / s for 10 minutes using a Henschel mixer, the hydrophobic particles having a volume average particle diameter of 12 nm 1.1 parts of functional silica (RY200, manufactured by Nippon Aerosil Co., Ltd.), blended for 5 minutes at a peripheral speed of 20 m / s, and removed coarse particles using a 45 μm mesh sieve to obtain a toner for developing an electrostatic latent image. It was. 100 parts of the carrier and 5 parts of the toner were stirred at 40 rpm for 20 minutes using a V-blender, and sieved with a sieve having a 177 μm mesh to obtain a developer. The obtained developer was put into the same remodeling machine as in Example 5, and the cleaning property was evaluated under the same conditions as in Example 5. As a result, there was no problem in image quality in any environmental condition, and no contamination of the charging roll was confirmed, which was good (D50ini (Cyan) = 0.1 μm, D50dest (Cyan) = 0.06 μm, D50dest (Cyan) / D50ini (Cyan) = 0.70).

[ Reference Example 3 ]
After blending 100 parts of the cyan toner of the colored particles with 3 parts of the lubricant-containing hollow particles (G) as an external additive at a peripheral speed of 32 m / s for 10 minutes using a Henschel mixer, the hydrophobic particle having a volume average particle diameter of 21 nm 1 part of water-soluble titanium oxide (T805, manufactured by Nippon Aerosil Co., Ltd.) and 1 part of hydrophobic silica (RX50, manufactured by Nippon Aerosil Co., Ltd.) having a volume average particle size of 40 nm are added and blended at a peripheral speed of 20 m / s for 5 minutes. Coarse particles were removed using a sieve to obtain an electrostatic latent image developing toner. 100 parts of the carrier and 5 parts of the toner were stirred at 40 rpm for 20 minutes using a V-blender, and sieved with a sieve having a 177 μm mesh to obtain a developer. The obtained developer was put into the same remodeling machine as in Example 5, and the cleaning property was evaluated under the same conditions as in Example 5. As a result, there was no problem in image quality under any environmental condition, and no contamination of the charging roll was confirmed, which was good (D50ini (Cyan) = 2μm, D50dest (Cyan) = 0.6μm, D50dest (Cyan) / D50ini (Cyan) = 0.30).

[ Reference Example 4 ]
After blending 100 parts of the cyan toner of the colored particles with 3 parts of the lubricant-containing hollow particles (H) as an external additive for 10 minutes at a peripheral speed of 32 m / s using a Henschel mixer, the hydrophobic particles having a volume average particle diameter of 12 nm 1 part of functional silica (RY200, manufactured by Nippon Aerosil Co., Ltd.) and 1 part of hydrophobic silica (RX50, manufactured by Nippon Aerosil Co., Ltd.) having a volume average particle size of 40 nm, blended for 5 minutes at a peripheral speed of 20 m / s, and sieved with a 45 μm mesh Coarse particles were removed using a toner to obtain an electrostatic latent image developing toner. 100 parts of the carrier and 5 parts of the toner were stirred at 40 rpm for 20 minutes using a V-blender, and sieved with a sieve having a 177 μm mesh to obtain a developer. The obtained developer was put into the same remodeling machine as in Example 5, and the cleaning property was evaluated under the same conditions as in Example 5. As a result, there was no problem in image quality under any environmental condition, and no contamination of the charging roll was confirmed, which was good (D50ini (Cyan) = 2μm, D50dest (Cyan) = 1.0μm, D50dest (Cyan) / D50ini (Cyan) = 0.5).

[Comparative Example 5]
To 100 parts of the cyan toner of the above colored particles, as an external additive, 3 parts of zinc stearate fine particles having a volume average particle diameter of 5 μm and 1 part of hydrophobic silica having a mean particle diameter of 12 nm (RY200, manufactured by Nippon Aerosil Co., Ltd.) Add 1 part of hydrophobic silica (RX50, manufactured by Nippon Aerosil Co., Ltd.) with a particle size of 40 nm, blend for 5 minutes at a peripheral speed of 20 m / s, remove coarse particles using a 45 μm mesh sieve, and use for electrostatic latent image development A toner was obtained. 100 parts of the carrier and 5 parts of the toner were stirred at 40 rpm for 20 minutes using a V-blender, and sieved with a sieve having a 177 μm mesh to obtain a developer. The obtained developer was put into the same remodeling machine as in Example 5, and the cleaning property was evaluated under the same conditions as in Example 5. As a result, in the low-temperature, low-humidity environment, cleaning failure has occurred in the 5 00 sheets. Further, the charging roll was very dirty, and image quality deterioration due to uneven charging occurred remarkably. Even at room temperature and humidity and high temperature and high humidity environment, although not as low temperature and low humidity environment, cleaning failure occurred in the middle, dirt on the charging roll was also observed, and image quality deterioration due to uneven charging occurred significantly (D50ini (Cyan) = 4.8 μm, D50dest (Cyan) = 4.3 μm, D50dest (Cyan) / D50ini (Cyan) = 0.9).

[Comparative Example 6 ]
100 parts of the cyan toner of the above colored particles, 3 parts of lubricant-containing hollow particles (J) as external additives, 1 part of hydrophobic silica (RY200, Nippon Aerosil Co., Ltd.) having a volume average particle diameter of 12 nm, volume average Add 1 part of hydrophobic silica (RX50, manufactured by Nippon Aerosil Co., Ltd.) with a particle size of 40 nm, blend for 5 minutes at a peripheral speed of 20 m / s, remove coarse particles using a 45 μm mesh sieve, and develop electrostatic latent image A toner was obtained. 100 parts of the carrier and 5 parts of the toner were stirred at 40 rpm for 20 minutes using a V-blender, and sieved with a sieve having a 177 μm mesh to obtain a developer. The obtained developer was put into the same remodeling machine as in Example 5, and the cleaning property was evaluated under the same conditions as in Example 5. As a result, in a low-temperature and low-humidity environment, cleaning failure occurred with 500 sheets. At that time, the photosensitive member and the charging roll were very dirty, and the image quality deteriorated remarkably. Even in normal temperature and high humidity environments, although not as low as low temperature and low humidity environments, cleaning defects occurred in the middle, as well as contamination of photoconductors and charging rolls, and image quality degradation was noticeable (D50ini ( Cyan) = 1.9 μm, D50dest (Cyan) = 0.29 μm, D50dest (Cyan) / D50ini (Cyan) = 0.15).

The results in the above Examples , Reference Examples and Comparative Examples are summarized in Table 2 below. The left column of the results shown in Table 2 below is the number of sheets until a cleaning failure occurs, and the right column is the cleaning performance evaluation result obtained from the values in the left column according to the evaluation criteria shown below.
○: No problem up to 50000 sheets Δ: Cleaning failure occurred at 10,000 to 40000 sheets ×: Cleaning failure occurred at 1000 to 10000 sheets XX: Cleaning failure occurred at 1 to 1000 sheets

When the toner containing the lubricant-containing particles defined in the present invention was used on the surface, good cleaning properties could be obtained regardless of the environment. On the other hand, a toner developer having no lubricant-containing particles was difficult to show good cleaning characteristics regardless of the environment, as in the results of Comparative Example 5. In the case of using a toner having a lubricant-containing hollow particles out of the provisions of the present invention as the ratio Comparative Examples 6, it could also be confirmed photosensitive member or contamination of the charging roller from the point of 500 th.

  In each developer evaluation, the photoreceptor was extracted after copying 20,000 sheets, and the surface was observed. The scratches and contamination were slight. On the other hand, when the developer containing no lubricant-containing hollow particles of the present invention is used, when the developers of Comparative Examples 5, 6, and 7 are used, the photoreceptor is extracted after copying 20,000 sheets, and the surface Upon observation, scratches and toner adhesion were clearly confirmed.

FIG. 3 is an explanatory diagram of a toner dam formed between a cleaning blade and an image carrier. 1 is a schematic view of an image forming apparatus having a cleaning blade. FIG. 3 is a schematic view of another image forming apparatus having a cleaning blade.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Image carrier (photoconductor), 2 Cleaning blade, 3 Tip part of cleaning blade, 4 Toner dam, 5 Charging means (charger), 6 Image input device (latent image forming means), 7 Developer (developing means), DESCRIPTION OF SYMBOLS 8 Transfer device (transfer means), 9 Cleaning device (cleaning means), 10 To-be-recorded body (transfer object), 11 Fixing device (fixing means), 12 Static elimination device (static elimination means), 13 Image forming apparatus, 15 Power supply, 20 solid lubricant, 21 cleaning brush, 23 image forming apparatus.

Claims (5)

A cleaning process in which the electrostatic latent image formed on the image carrier is developed with a developer containing toner to form a toner image, the toner image is transferred, and then the toner remaining on the image carrier is removed with a cleaning blade. An electrostatic latent image developing toner used in an image forming method comprising:
The electrostatic latent image developing toner comprises toner particles containing at least a binder resin and a colorant, and an external additive.
The toner particles have a volume average particle size of 2 μm to 10 μm,
External additive has a volume average particle diameter or less of a volume average particle diameter 100nm or more and toner particles, the void ratio of 40% to 80% of inorganic hollow particles child or Rannahli, a further external additive is the following conditions An electrostatic latent image developing toner characterized by satisfying.
[Equation 1]
0.2 ≦ D50dest / D50ini ≦ 0.85
(Here, D50ini represents the volume average particle diameter D50 of the external additive adhering to the toner particles in the toner before development. D50dest represents when the residual toner on the image carrier is removed by the cleaning blade. (This represents the volume average particle diameter D50 of the external additive present in the tip portion.) A cleaning process in which the electrostatic latent image formed on the image carrier is developed with a developer containing toner to form a toner image, the toner image is transferred, and then the toner remaining on the image carrier is removed with a cleaning blade. An electrostatic latent image developing toner used in an image forming method comprising:
The electrostatic latent image developing toner comprises toner particles containing at least a binder resin and a colorant, and an external additive.
The toner particles have a volume average particle size of 2 μm to 10 μm,
External additive has a volume average particle diameter or less of a volume average particle diameter of 100nm or more and toner particles, or the void ratio of 40% to 80% of inorganic hollow particles are encapsulated lubricant lubricant-containing inorganic particles child And a toner for developing an electrostatic latent image, wherein the external additive satisfies the following conditions.
[Equation 2]
0.2 ≦ D50dest / D50ini ≦ 0.85
(Here, D50ini represents the volume average particle diameter D50 of the external additive adhering to the toner particles in the toner before development. D50dest represents when the residual toner on the image carrier is removed by the cleaning blade. (This represents the volume average particle diameter D50 of the external additive present in the tip portion.)   An electrostatic latent image developing developer comprising the electrostatic latent image developing toner according to claim 1 or 2 and a carrier. The electrostatic latent image formed on the image carrier is developed with a developer containing toner to form a toner image. After the toner image is transferred, the toner remaining on the image carrier is removed with a cleaning blade. In the image forming method having a cleaning step,
The toner comprises toner particles containing at least a binder resin and a colorant, and an external additive. The toner particles have a volume average particle diameter of 2 μm to 10 μm, and the external additive has a volume average particle diameter of 100 nm. and a volume average particle diameter or less of a toner particle, the void ratio of 40% to 80% of inorganic hollow particles child or Rannahli further external additive toner is used for satisfying the electrostatic latent image developing below or An image forming method.
[Equation 3]
0.2 ≦ D50dest / D50ini ≦ 0.85
(Here, D50ini represents the volume average particle diameter D50 of the external additive adhering to the toner particles in the toner before development. D50dest represents when the residual toner on the image carrier is removed by the cleaning blade. (This represents the volume average particle diameter D50 of the external additive present in the tip portion.) The electrostatic latent image formed on the image carrier is developed with a developer containing toner to form a toner image. After the toner image is transferred, the toner remaining on the image carrier is removed with a cleaning blade. In the image forming method having a cleaning step,
The toner comprises toner particles containing at least a binder resin and a colorant, and an external additive.
The toner particles have a volume average particle size of 2 μm to 10 μm,
External additive has a volume average particle diameter or less of a volume average particle diameter of 100nm or more and toner particles, or the void ratio of 40% to 80% of inorganic hollow particles are encapsulated lubricant lubricant-containing inorganic particles child And the external additive is an electrostatic latent image developing toner that satisfies the following conditions.
[Equation 4]
0.2 ≦ D50dest / D50ini ≦ 0.85
(Here, D50ini represents the volume average particle diameter D50 of the external additive adhering to the toner particles in the toner before development. D50dest represents when the residual toner on the image carrier is removed by the cleaning blade. (This represents the volume average particle diameter D50 of the external additive present in the tip portion.)

Images