JP2012068526A - Toner for electrostatic charge image development, manufacturing method of toner for electrostatic charge image development, developer, and image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide toner for electrostatic charge image development that has excellent transfer efficiency of a toner image and improved cleaning property of residual toner.SOLUTION: Toner for electrostatic charge image development includes toner base particles having fluorocarbon polymer particles adhered on the surface of a center particle and having a volume average value of a ratio X, which is peripheral measurement (PM)/equivalent circle diameter (D), of 3.6 or more to 5.0 or less.

Description

  The present invention relates to a toner for developing an electrostatic image, a method for producing a toner for developing an electrostatic image, a developer, and an image forming method.

In the image formation in the electrophotographic process, at the time of copying, toner is attached to an electrostatic latent image formed on a photoconductor using a photoconductive substance by a magnetic brush developing method or the like, and developed as a toner image. After the toner image on the body is transferred to a recording material (transfer material) such as paper or sheet, it is fixed using heat, solvent, pressure or the like to obtain a permanent image.
In image formation using this toner, maintenance of toner image transfer efficiency and residual toner cleaning properties are important.

  Patent Document 1 has a resin composition protrusion having a cross-linked structure on the surface of a toner, the difference between the solubility parameter of the toner base particles and the solubility parameter of the resin composition is in a specific range, and the toner is specified. The toner has a shape factor and specifies the ratio between the outer diameter of the protrusion and the volume average particle diameter of the toner base particles.

  Patent Document 2 discloses an electrophotographic toner containing a binder resin and a colorant and having a core-shell structure, the core mainly containing a crystalline resin, and the shell is 15% by mass or more and 120% by mass with respect to the core. An electrophotographic toner is disclosed, wherein the shell has hemispherical protrusions having a step of 0.3 μm or more, and the shell is produced by an emulsion aggregation method. Further, in Patent Document 2, a fine particle dispersion of a shell-forming resin is mixed with a core dispersion containing a binder resin mainly composed of a crystalline resin and a colorant, and the shell-forming resin is mixed on the core surface. It is disclosed that fine particles are adhered and aggregated.

  In Patent Document 3, at least a coloring material, a release material, a binder resin, and an organic conceptual diagram I / O value specified in a specific numerical range are dissolved or dispersed in a solvent, and O / W type wet A spherical toner having a circularity of 0.970 or more is formed by the granulation method, and the toner core surface is integrated with an average particle diameter of 150 nm to 500 nm and a coverage of 10% to 80% with respect to the toner core surface. In addition, a toner for developing an electrostatic image having a controlled structure and forming a granular convex portion is disclosed.

  Patent Document 4 discloses a toner obtained by adhering inorganic fine particles to toner base particles having the following surface properties in a toner composed of at least a binder resin and a colorant. (1) The surface roughness Ra is 1 to 30 nm, (2) the standard deviation RMS of the surface roughness is 10 to 90 nm, and (3) the height difference from the bottom of the concave portion to the top of the convex portion is 10 nm or more. The number of convex portions is 1 to 20 / μm.

  Patent Document 5 includes toner base particles containing a binder resin and a colorant and an additive. The toner base particles have a volume average particle size in the range of 80 to 300 nm and a shape factor SF1 of 100. For electrostatic image development in which hydrophobic silica in the range of ˜120 is contained in a layer of 0.04 to 1 μm from the surface of the toner base particles, and the volume average particle size of the additive is in the range of 80 to 300 nm. Toner is disclosed.

JP 2008-158319 A JP 2005-274964 A JP 2008-233430 A JP 2004-246344 A JP 2008-046416 A

  The problem to be solved by the present invention is to provide a toner for developing an electrostatic charge image that is excellent in toner image transfer efficiency and further improves the cleaning property of residual toner.

The above problems have been solved by the following means <1>, <7>, <8> and <9>. It is listed together with preferred embodiments <2> to <6>.
<1> The toner base particles having fluoropolymer particles adhered to the surface of the center particles have a ratio X of the peripheral length (PM) / equivalent circle diameter (D) of 3.6 to 5.0. An electrostatic charge image developing toner,
<2> The toner for developing an electrostatic charge image according to <1>, wherein the volume average value of the particle size of the fluoropolymer particles is 150 to 500 nm.
<3> The electrostatic charge image developing toner according to <1> or <2>, wherein the binder resin of the central particle is a polyester resin or an acrylic resin.
<4> For electrostatic image development according to any one of <1> to <3>, wherein the fluoropolymer particles contain 0.1 to 30 parts by weight of a fluorine compound with respect to 100 parts by weight of the resin. toner,
<5> Any one of <1> to <4>, wherein the number average value of the ratio of the projected area of the fluoropolymer particles to the total projected area of the toner base particles by SEM observation is 20 to 80%. Toner for developing an electrostatic image according to claim 1,
<6> An aggregation step of aggregating a dispersion containing at least a binder resin and a colorant to form an aggregate, a particle adhesion step of adhering fluoropolymer particles to the surface of the aggregate, and an adhesion to the aggregate A method for producing a toner for developing electrostatic images according to any one of <1> to <5>, comprising a fusing step of fusing and coalescing the particles of the fluoropolymer.
<7> A developer containing the electrostatic image developing toner according to any one of <1> to <5> and a carrier,
<8> A latent image forming step of forming an electrostatic latent image on the surface of the image carrier and an electrostatic latent image formed on the surface of the image carrier are any one of <1> to <5> A developing process for forming the toner image by developing with the toner for developing an electrostatic charge image according to 1 or the developer according to <7>, a transfer process for transferring the toner image to the surface of the recording medium, and a transfer process. A fixing step of fixing the toner image onto a recording medium.

According to the invention described in <1> above, the toner for developing an electrostatic charge image is capable of suppressing a decrease in transfer efficiency of the toner image and maintaining the cleaning property even when a large number of images are output at high speed. Can be provided.
According to the invention described in <2>, the electrostatic charge image development that can further suppress the reduction in the transfer efficiency of the toner image and can maintain the cleaning property even when a large number of images are output at high speed. Toner can be provided.
According to the invention described in <3>, the electrostatic charge image development that can further suppress the reduction in the transfer efficiency of the toner image and can maintain the cleaning property even when a large number of images are output at high speed. Toner can be provided.
According to the invention described in <4>, the electrostatic charge image development that can further suppress the reduction in the transfer efficiency of the toner image and can maintain the cleaning property even when a large number of images are output at high speed. Toner can be provided.
According to the invention described in <5> above, even when a large number of images are output at high speed, the reduction in the transfer efficiency of the toner image is further suppressed, and the electrostatic charge image development that can maintain the cleaning property can be further performed. Toner can be provided.
According to the invention described in <6>, for electrostatic image development that is capable of suppressing a decrease in transfer efficiency of a toner image and maintaining cleaning properties even when a large number of images are output at high speed. A toner production method can be provided.
According to the invention described in the above <7>, there is provided a developer capable of further suppressing a reduction in toner image transfer efficiency and maintaining a cleaning property even when a large number of images are output at high speed. be able to.
According to the invention described in <8>, an image forming method is provided in which a decrease in toner image transfer efficiency is further suppressed and cleaning performance can be maintained even when a large number of images are output at high speed. can do.

2 is an electron micrograph showing an example of an electrostatic charge image developing toner of the present embodiment. 1 is a schematic cross-sectional view illustrating an example of an image forming apparatus according to an exemplary embodiment.

  Hereinafter, the present embodiment will be described.

(Static image developing toner)
The toner for developing an electrostatic charge image (hereinafter, also simply referred to as “toner”) of the present embodiment has a peripheral length (PM) / equivalent circle diameter of toner base particles having fluoropolymer particles attached to the surface of center particles. The ratio X of (D) is 3.6 or more and 5.0 or less (3.6 to 5.0). In addition, the value of the ratio X is a volume average value.

  In the present embodiment, the description “A to B” represents not only a range between A and B but also a range including A and B at both ends thereof. For example, if “A to B” is a numerical value range, “A or more and B or less” or “B or more and A or less” is represented.

The above X measurement method is calculated by observing toner base particles without external additives with an electron microscope and image-processing them. The volume average is an average value for 50 toner particles. A method for separating the toner base particles having no external additive from the toner in the presence of the external additive will be described in Examples.
When the value of X is less than 3.6, the surface of the toner particles has few irregularities, and the transfer efficiency and the cleaning property tend to be inferior. As the number of particles increases, the particle shape becomes unstable, and the transfer efficiency and cleaning properties tend to be inferior.
The value of X is preferably 3.6 to 4.2, and more preferably 3.6 to 3.8.

FIG. 1 is an electron micrograph showing an example of the toner for developing an electrostatic charge image of this embodiment.
As shown in FIG. 1, the toner for developing an electrostatic charge image of this embodiment contains toner mother particles having fluoropolymer particles attached to the surface of the center particles. The circle equivalent diameter of the toner base particles is preferably 2 to 8 μm, and more preferably 2 to 4 μm. The particle diameter of the fluoropolymer particles attached to the surface of the toner base particles is preferably 150 to 500 nm in terms of volume average.
The materials for the center particles and the adhered particles will be described later.

  Hereinafter, a toner constituent material used in the exemplary embodiment, a toner manufacturing method, and the like will be described.

<Binder resin>
In the toner according to the exemplary embodiment, the center particle contains at least a binder resin. The binder resin is not particularly limited, and examples thereof include addition polymerization resins and polycondensation resins. Among these, addition polymerization resins of ethylenically unsaturated compounds are preferable as addition polymerization resins, acrylic resins are more preferable, polyester resins are preferable as polycondensation resins, and polyester resins of polyols and polycarboxylic acids are more preferable.
Details are described below.

As the addition polymerization resin, homopolymers and copolymers of various ethylenically unsaturated compounds are preferably used. Examples of addition polymerization resins for ethylenically unsaturated compounds 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 acetate. , Α-methylene aliphatic monocarboxylic acids such as methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, dodecyl methacrylate Examples include homopolymers or copolymers of vinyl ethers such as esters, vinyl methyl ether, vinyl ethyl ether, vinyl butyl ether, vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, and vinyl isopropenyl ketone. It is.
Particularly preferred addition polymerization resins include polystyrene, styrene-alkyl acrylate copolymer, styrene-alkyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, and styrene-anhydrous maleate. Examples include acid copolymers, polyethylene, and polypropylene.

An example of the polycondensation resin used in the present embodiment is a polyester resin, which is synthesized from a polyol component and a polycarboxylic acid component by polycondensation. In addition, in this embodiment, a commercial item may be used as said polyester resin, and what was synthesize | combined suitably may be used.
Examples of the polyvalent carboxylic acid component include oxalic acid, succinic acid, glutaric acid, adipic acid, peric acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1,12 -Aliphatic dicarboxylic acids such as dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid, phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid, malonic acid, mesaconic acid Aromatic dicarboxylic acids such as dibasic acids such as these, and in addition, these anhydrides and lower alkyl esters thereof are also included.
Examples of the trivalent or higher carboxylic acid include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, and the like, anhydrides thereof, and the like. And lower alkyl esters. These may be used individually by 1 type and may use 2 or more types together.

  Furthermore, it is more preferable to contain the dicarboxylic acid component which has an ethylenically unsaturated bond other than the above-mentioned aliphatic dicarboxylic acid and aromatic dicarboxylic acid. A dicarboxylic acid having an ethylenically unsaturated bond is preferably used to prevent hot offset at the time of fixing because it is radically crosslinked through the ethylenically unsaturated bond. Examples of such dicarboxylic acids include, but are not limited to, maleic acid, fumaric acid, 3-hexenedioic acid, and 3-octenedioic acid. In addition, these lower esters, acid anhydrides and the like are also included. Among these, fumaric acid, maleic acid and the like are preferable in terms of cost.

Examples of the polyhydric alcohol component include polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane and polyoxyethylene (2.2) -2,2-bis. Bisphenol A alkylene (2 to 4 carbon) oxide adducts (average addition mole number 1.5 to 6) such as (4-hydroxyphenyl) propane, ethylene glycol, propylene glycol, neopentyl glycol, 1,4-butane Examples include diol, 1,3-butanediol, 1,6-hexanediol, and the like.
Examples of the trivalent or higher alcohols include sorbitol, pentaerythritol, glycerol, trimethylolpropane, and the like.
In the amorphous polyester resin (also referred to as “non-crystalline polyester resin”), among the raw material monomers described above, a dihydric or higher secondary alcohol and / or a divalent or higher aromatic carboxylic acid compound is preferable. Examples of the dihydric or higher secondary alcohol include a propylene oxide adduct of bisphenol A, propylene glycol, 1,3-butanediol, and glycerol. In these, the propylene oxide adduct of bisphenol A is preferable.
As the divalent or higher aromatic carboxylic acid compound, terephthalic acid, isophthalic acid, phthalic acid and trimellitic acid are preferable, and terephthalic acid and trimellitic acid are more preferable.
Moreover, softening point 90-160 degreeC, glass transition point 50-80 degreeC, number average molecular weight 2,000-10,000, weight average molecular weight 10,000-150,000, acid value 10-30 mgKOH / g, hydroxyl value 5 A resin exhibiting ˜30 mg KOH / g is particularly preferably used.

In order to impart low-temperature fixability to the toner, it is preferable to use a crystalline polyester resin as at least a part of the binder resin.
The crystalline polyester resin is preferably composed of an aliphatic dicarboxylic acid and an aliphatic diol, and more preferably a linear dicarboxylic acid or a linear aliphatic diol having 4 to 20 carbon atoms in the main chain portion. The linear type is excellent in the crystallinity of the polyester resin and has an appropriate crystal melting point, and thus is excellent in toner blocking resistance, image storage stability, and low-temperature fixability. Further, when the carbon number is 4 or more, the ester bond concentration is low, the electric resistance is moderate, and the toner charging property is excellent. Further, when it is 20 or less, it is easy to obtain practical materials. The carbon number is more preferably 14 or less.

Examples of the aliphatic dicarboxylic acid suitably used for the synthesis of the crystalline polyester include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelinic acid, sebacic acid, 1,9-nonane. Dicarboxylic acid, 1,10-decanedicarboxylic acid, 1,11-undecanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1,13-tridecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,16-hexadecanedicarboxylic acid An acid, 1,18-octadecanedicarboxylic acid or the like, or a lower alkyl ester or an acid anhydride thereof may be mentioned, but not limited thereto. Among these, considering availability, sebacic acid and 1,10-decanedicarboxylic acid are preferable.
Specific examples of the aliphatic diol include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, and 1,7-heptanediol. 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol 1,18-octadecanediol, 1,20-eicosanediol and the like, but are not limited thereto. Among these, 1,8-octanediol, 1,9-nonanediol, and 1,10-decanediol are preferable in view of availability.
Examples of the trivalent or higher alcohol include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol and the like. These may be used individually by 1 type and may use 2 or more types together.

Among the polyvalent carboxylic acid components, the content of the aliphatic dicarboxylic acid is preferably 80 mol% or more, and more preferably 90 mol% or more. When the content of the aliphatic dicarboxylic acid is 80 mol% or more, the polyester resin is excellent in crystallinity and has an appropriate melting point, so that it is excellent in toner blocking resistance, image storage stability, and low-temperature fixability.
Among the polyhydric alcohol components, the content of the aliphatic diol component is preferably 80 mol% or more, and more preferably 90 mol% or more. When the content of the aliphatic diol component is 80 mol% or more, the polyester resin is excellent in crystallinity and has an appropriate melting point, so that it is excellent in toner blocking resistance, image storage stability, and low-temperature fixability.
If necessary, a monovalent acid such as acetic acid or benzoic acid or a monovalent alcohol such as cyclohexanol benzyl alcohol may be used for the purpose of adjusting the acid value or the hydroxyl value.

The production method of the polyester resin is not particularly limited, and can be produced by a general polyester polymerization method in which an acid component and an alcohol component are reacted. Examples thereof include direct polycondensation and transesterification. Depending on the type, it will be manufactured separately.
The polyester resin may be produced by subjecting the polyhydric alcohol and polyhydric carboxylic acid to a condensation reaction according to a conventional method. For example, the above polyhydric alcohol and polyvalent carboxylic acid, if necessary, a catalyst is added, blended in a reaction vessel equipped with a thermometer, a stirrer, a flow-down condenser, and in the presence of an inert gas (such as nitrogen gas), Heat at 150 to 250 ° C. to continuously remove by-product low-molecular compounds out of the reaction system, stop the reaction when a predetermined acid value is reached, cool, and obtain the desired reactant Manufactured by.

  Further, the content of the binder resin in the toner of the exemplary embodiment is not particularly limited, but is preferably 5 to 95% by weight with respect to the total weight of the electrostatic image developing toner, and 20 to 90% by weight. %, More preferably 40 to 85% by weight. Within the above range, the fixing property, storage property, powder property, charging property and the like are excellent.

<Release agent>
The toner of the exemplary embodiment preferably contains a release agent. The release agent is preferably contained in the center particle.

  There is no restriction | limiting in particular in the mold release agent used for this embodiment, A well-known thing is used and what is obtained from the following waxes is preferable. Paraffin wax and derivatives thereof, montan wax and derivatives thereof, microcrystalline wax and derivatives thereof, Fischer-Tropsch wax and derivatives thereof, polyolefin wax and derivatives thereof, and the like. Derivatives include oxides, polymers with vinyl monomers, and graft modified products. In addition, alcohols, fatty acids, plant waxes, animal waxes, mineral waxes, ester waxes, acid amides and the like are also used.

  The wax used as a release agent is preferably melted at any temperature of 70 to 140 ° C. and exhibits a melt viscosity of 1 to 200 centipoise, more preferably 1 to 100 centipoise. When the melting temperature is 70 ° C. or higher, the change temperature of the wax is sufficiently high, and the blocking resistance and the developability are excellent when the temperature in the copying machine is increased. When the temperature is 140 ° C. or lower, the change temperature of the wax is sufficiently low, it is not necessary to perform fixing at a high temperature, and the energy saving property is excellent. Further, when the melt viscosity is 200 centipoises or less, the elution from the toner is appropriate and the fixing peelability is excellent.

  The content of the releasing agent is preferably 3 to 60% by weight, more preferably 5 to 40% by weight, and 7 to 20% by weight based on the total weight of the toner. Is more preferable. Within the above range, the toner is more excellent in preventing the toner from being offset to the heating member, and more excellent in preventing the feed roll from being contaminated.

<Colorant>
The toner of the exemplary embodiment preferably contains a colorant. The colorant is preferably contained in the center particle.
Examples of colorants include carbon black, nigrosine, aniline blue, calcoil blue, chrome yellow, ultramarine blue, dupont oil red, quinoline yellow, methylene blue chloride, phthalocyanine blue, malachite green oxalate, 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 red 238, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 180, C.I. I. Pigment blue 15: 1, C.I. I. Pigment Blue 15: 3 is exemplified as a representative example.
A coloring agent is used individually by 1 type or in combination of 2 or more types.

  In the toner of this embodiment, the colorant is selected from the viewpoints of hue angle, saturation, brightness, weather resistance, OHP permeability, and dispersibility in the toner. The amount of the colorant added is not particularly limited, but is preferably in the range of 3 to 60% by weight with respect to the total weight of the toner.

<Other toner additives>
In addition to the above-described components, various components such as an internal additive, a charge control agent, inorganic powder (inorganic particles), and organic particles may be added to the toner of the exemplary embodiment as necessary. Good.
Examples of the internal additive include metals such as ferrite, magnetite, reduced iron, cobalt, nickel and manganese, alloys, and magnetic materials such as compounds containing these metals.
Examples of the charge control agent include quaternary ammonium salt compounds, nigrosine compounds, dyes composed of complexes of aluminum, iron, chromium, and triphenylmethane pigments.
The inorganic powder is added to the toner mainly for the purpose of adjusting the viscoelasticity of the toner. For example, silica, alumina, titania, calcium carbonate, magnesium carbonate, calcium phosphate, cerium oxide, etc. All inorganic particles used as

  The volume average particle size of the toner base particles of the exemplary embodiment is preferably 2 to 9 μm, and more preferably 3 to 7 μm. Within the above range, the chargeability, developability, and image resolution are excellent.

Further, the toner base particles of the present embodiment preferably have a volume average particle size distribution index GSDv of 1.30 or less. When the volume distribution index GSDv is 1.30 or less, the image resolution is excellent.
In this embodiment, the toner particle size and the value of the volume average particle size distribution index GSDv are measured and calculated as follows. First, the toner particle size distribution measured using a measuring instrument such as Coulter Counter TAII (Beckman Coulter), Multisizer II (Beckman Coulter), etc. A cumulative distribution is drawn from the small diameter side with respect to the volume of the toner particles, and the particle diameter of 16% is defined as the volume average particle diameter D _16v, and the particle diameter of 50% is defined as the volume average particle diameter D _50v. To do. Similarly, the particle size at a cumulative 84% is defined as the volume average particle size D _84v . At this time, the volume average particle size distribution index (GSDv) is calculated using these relational expressions defined as D _84v / D _16v .

The toner base particles of the present embodiment preferably have a shape factor SF1 (= ((absolute maximum length of toner diameter) ² / toner projected area) × (π / 4) × 100) in the range of 100 to 150. The range of 110 to 130 is more preferable.
Note that the value of the shape factor SF1 indicates the roundness of the toner, which is 100 in the case of a true sphere, and increases as the shape of the toner becomes indefinite. Further, the values required for calculation using the shape factor SF1, that is, the absolute maximum length of the toner diameter and the projected area of the toner are enlarged to 500 times magnification using an optical microscope (Nikon Corporation, Microphoto-FXA). The obtained toner particle image was photographed, and the obtained image information was obtained by introducing the image information into an image analyzer (Luzex III) manufactured by Nireco Co., Ltd. via an interface and performing image analysis. The average value of the shape factor SF1 was calculated based on data obtained by measuring 1,000 toner particles sampled randomly.
When the shape factor SF1 is 100 or more, the generation of residual toner in the transfer process during image formation is suppressed, and the cleaning property when cleaning with a blade or the like is excellent, and as a result, image defects are suppressed. On the other hand, when the shape factor SF1 is 150 or less, when the toner is used as a developer, the toner is prevented from being destroyed by collision with the carrier in the developing device, and as a result, the generation of fine powder is suppressed. As a result, the surface of the photoreceptor is prevented from being contaminated by the release agent component exposed on the toner surface, and not only the charging characteristics are excellent, but also the occurrence of fog caused by fine powder is suppressed.

<Fluoropolymer particles>
In the toner according to the present exemplary embodiment, the volume average value of the ratio X of the peripheral length (PM) / equivalent circle diameter (D) of the toner base particles having fluoropolymer particles attached to the surface of the central particles is 3.6 or more and 5 In order to make it 0.0 or less, the volume average value of the particle diameter of the fluoropolymer particles adhering to the surface of the toner base particles is preferably 150 to 500 nm. When the thickness is in the range of 150 to 500 nm, the cleaning property can be more maintained. If the thickness is less than 150 nm, the toner surface is smooth and inferior in cleaning properties. 300-400 nm is more preferable.

The fluoropolymer particles preferably contain 0.1 to 30 parts by weight of a fluorine compound with respect to 100 parts by weight of the resin. Specific examples of the fluorine compound used include perfluorohexyl ethylene, 2,2,2-trifluoroethyl acrylate, 2,2,2-trifluoroethyl methacrylate, 2,2,3,3- Tetrafluoropropyl acrylate, 1H, 1H, 5H-octafluoropentyl acrylate, 1H, 1H, 5H-octafluoropentyl methacrylate, 2- (perfluorobutyl) ethyl methacrylate, 2- (perfluorohexyl) ethyl methacrylate, methacrylic acid And trifluoroethyl. The method for polymerizing these monomers is not particularly limited, and can be produced by a general addition polymerization method. Examples thereof include an emulsion polymerization method, a mini-emulsion method, a suspension polymerization method, and the like. To manufacture.
Examples of the polycondensation monomer include tetrafluorophthalic acid, tetrafluoroterephthalic acid, 2,3,5,6-tetrafluorophenyl dimethanol and the like.
The production method of the polyester resin is not particularly limited, and can be produced by a general polyester polymerization method in which an acid component and an alcohol component are reacted. Examples thereof include direct polycondensation and transesterification. Depending on the type, it will be manufactured separately.
The fluoropolymer particles are fixed to the toner base particles. In this respect, it is a fluidizing agent and is different from an external additive that is not fixed to the toner base particles.

<Toner shape>
In the toner particles of the present embodiment, the number average value of the ratio of the projected area of the fluoropolymer particles to the total projected area of the toner base particles by SEM observation is preferably 20 to 80%, and preferably 30 to 70%. Preferably there is. When the amount falls within the above range, the adhesion force of the toner can be further reduced, so that a decrease in transfer maintenance can be further suppressed.

<Method for producing toner for developing electrostatic image>
The toner manufacturing method of the present embodiment includes an aggregation step of aggregating a dispersion containing at least a binder resin and a colorant to form an aggregate, and a particle adhesion step of adhering fluoropolymer particles to the surface of the aggregate. And a fusing step of fusing and coalescing the aggregate and the adhering fluoropolymer particles.
In the aggregating step, it is preferable to aggregate the dispersion containing the release agent particles in addition to the binder resin and the colorant to form an aggregate.

The particle attaching step is a step of attaching a fluoropolymer particle to the outside of the core particle while covering the surface of the core particle with a shell layer after the core particle forming step of forming the core particle of the toner. It is preferable. In addition, the step of coating the shell layer on the outside of the core particles and the step of attaching the fluoropolymer particles on the outside of the core particles may be performed simultaneously or partially overlapping. Also good. In this case, the binder resin dispersion used for forming the core particles and coating the shell layer may be a dispersion containing the same kind of binder resin or a dispersion containing a different kind of binder resin. .
The adhesion of the fluoropolymer particles is performed by adjusting the pH of the dispersion to be used, adding the binder resin dispersion used to coat the shell layer, and then setting the pH higher than the binder resin dispersion. It is preferable to carry out by additionally adding a dispersion of the adjusted fluoropolymer particles. For example, it is preferable to first add a dispersion of a binder resin used for coating a shell layer adjusted to pH 2.5, and then add a dispersion of fluoropolymer particles adjusted to pH 4.3.
The shelled core particles correspond to toner base particles.

As a method for producing the core particle of the toner, the polymerization of the polymerizable monomer particles and / or the polymer particles in an aqueous medium such as a suspension polymerization method, an emulsion aggregation method, a seed polymerization method, and a swelling polymerization method are preferably performed. There is a method of forming the toner by forming the toner. Furthermore, it is preferable to use a wet production method, particularly an emulsion aggregation method, because it is easy to produce a toner having a structure in which core particles are coated with a shell layer containing particles.
In the emulsion aggregation method, an additive for imparting a function required for a toner such as an aqueous dispersion such as a colorant, a charge control agent, and a release agent to a resin particle dispersion prepared by emulsion polymerization or emulsion. The dispersion is mixed in an aqueous medium, and the dispersion is agglomerated using an aggregating agent while mechanically shearing using various dispersing machines such as a homomixer in the aqueous medium. Toner particles are obtained through a process of fusing particles to form core particles.

The emulsion aggregation method in the present embodiment includes a step of forming an aggregate that is a core particle, and a particle adhesion step in which a large number of fluoropolymer particles adhere to the surface of the aggregate.
In the previous step of forming the aggregate that is the core particle, the first resin particle dispersion liquid in which the first resin particles made of the first binder resin and having a volume average particle diameter of 1 μm or less are dispersed; An aggregating step of forming an aggregate by adding an aggregating agent to a mixed dispersion at least mixed with a colorant particle dispersion in which a colorant is dispersed, and heating, and a fusion step of fusing and coalescing the aggregate Including.
In the subsequent step of attaching the fluoropolymer particles to the surface of the coalesced aggregate, the mixed dispersion formed of the coalesced aggregates as core particles is made of the second binder resin and has a volume. Add the second resin particle dispersion liquid in which the second resin particles having an average particle size of 1 μm or less and containing fluoropolymer particles are dispersed, and attach the second resin particles to the surface of the core particles In this process, a large number of fluoropolymer particles are adhered to the surface of the core particle. It is preferable to include a fusing step for fusing and coalescing the entire core-shell particles to which the fluoropolymer particles are adhered after the particle adhering step.

  In the aggregation step, core particles (core aggregated particles) simply formed by aggregating various particle components in the mixed dispersion liquid may be formed, and the heating temperature is higher than the glass transition temperature of the first binder resin. You may form the core particle (core fusion particle) which made it high and united simultaneously with aggregation. Moreover, you may implement a fusion | melting process by heating above the higher temperature of the glass transition temperature of 1st or 2nd binder resin.

  In general, the emulsion aggregation method is a method in which a resin dispersion is prepared by emulsion polymerization or emulsification, while a release agent particle dispersion in which a release agent is dispersed, preferably a colorant particle in which a colorant is dispersed in a solvent. In this method, a dispersion liquid is prepared, and these are mixed to form aggregated particles (aggregation step), and then fused and united by heating (fusion step) to obtain toner particles. In addition, in this embodiment, it has a particle | grain adhesion process which adheres the particle | grains of many more fluoropolymers on the surface of an aggregation particle after an aggregation process and before a fusion | melting process.

  Next, a toner production method suitable for producing the toner of this embodiment will be described in more detail.

-Toner production method-
Next, the toner manufacturing method used in this embodiment including the above-described aggregation process, particle adhesion process, and fusion process will be described in detail for each process.

-Aggregation process-
In the aggregation step, first, the flocculant is added to the first binder resin dispersion, the release agent dispersion, preferably the colorant dispersion, and the mixed dispersion obtained by mixing other components, By heating at a temperature slightly lower than the melting point of the first binder resin, aggregated particles (core aggregated particles) obtained by aggregating particles composed of the respective components are formed. The fused particles (core fused particles) may be formed by heating at a temperature equal to or higher than the glass transition temperature of the first binder resin and performing fusion at the same time as aggregation.

Aggregated particles are formed by adding an aggregating agent at room temperature under stirring with a rotary shearing homogenizer. As the aggregating agent used in the aggregating step, a surfactant having a reverse polarity to the surfactant used as a dispersing agent for various dispersions, an inorganic metal salt, and a metal complex having a valence of 2 or more are preferably used.
In particular, the use of a metal complex is particularly preferable because the amount of the surfactant used can be reduced and the charging characteristics are improved.

  Examples of the inorganic metal salt include metal salts such as calcium chloride, calcium nitrate, barium chloride, magnesium chloride, zinc chloride, aluminum chloride, and aluminum sulfate, and polyaluminum chloride, polyaluminum hydroxide, and calcium polysulfide. Examples thereof include inorganic metal salt polymers. Among these, an aluminum salt and a polymer thereof are particularly preferable. In order to obtain a sharper particle size distribution, the valence of the inorganic metal salt is bivalent than monovalent, trivalent than divalent, tetravalent than trivalent, and even if the valence is the same, the polymerization type The inorganic metal salt polymer is more suitable.

-Particle adhesion process-
In the particle adhering step, the fluoropolymer particles and the second particles are formed on the surface or outside of the core particles (core agglomerated particles or core fusion particles) containing the first binder resin formed through the aggregating step. A coating layer is formed by adhering a mixture containing resin particles made of an adhesion resin (hereinafter, agglomerated particles provided with a coating layer on the surface of the core particles are also referred to as “particle-adhering agglomerated particles”). Here, this coating layer corresponds to the shell layer of the toner of the present embodiment formed through a fusion process described later.
As already explained, the core particle including the shell layer corresponds to the central particle.
The coating layer (shell layer) can be formed by additionally adding a dispersion of second resin particles containing fluoropolymer particles in the dispersion in which the core particles are formed in the aggregation step. In addition to the fluoropolymer particles, other components may be added at the same time as necessary.
The resin solid content weight of the resin particles used for forming the coating layer (the weight of the resin with shell) and the weight of the fluoropolymer particles are within the range of the weight of the resin with shell / the weight of the fluoropolymer particles = 10/90 to 70/30. Preferably there is.
Regarding the relationship between the melting point and the glass transition temperature between the fluoropolymer particles and the resin of the coating layer, it is preferable that the fluoropolymer particles are higher by 5 ° C. or more for both the melting point and the glass transition temperature. However, since a fluoropolymer is generally not very compatible with a general polymer, it tends to remain as particles even if the melting point or glass transition temperature is outside the above range.

When the resin particles made of the second binder resin and the fluoropolymer particles are uniformly attached to the surface of the core particles to form a coating layer, and the obtained particle-adhered aggregated particles are heated and fused in a fusion step described later. The resin particles made of the second binder resin contained in the coating layer on the surface of the core particles are melted to form a shell layer. For this reason, it is possible to effectively prevent the components such as the release agent contained in the core layer located inside the shell layer from being exposed to the toner surface.
The method for adding and mixing the second resin particle dispersion containing fluoropolymer particles in the particle adhering step is not particularly limited. For example, the method may be carried out gradually or divided into a plurality of times. It may be done step by step. In this way, by adding and mixing the second resin particle dispersion, the generation of fine particles is suppressed, and the particle size distribution of the obtained toner becomes sharp.
In the present embodiment, the number of times that this particle adhering step is performed may be one or a plurality of times. In the former case, only one layer mainly composed of the second binder resin is formed on the surface of the core aggregated particles. On the other hand, in the latter case, if not only the second resin particle dispersion but also a plurality of particle dispersions composed of a release agent dispersion and other components are used, a specific component is mainly contained on the surface of the core aggregated particles. A layer as a component is laminated.

  The latter case is advantageous in that a toner having a complicated and precise hierarchical structure can be obtained and a desired function can be imparted to the toner. When the adhesion process is performed a plurality of times or in multiple stages, the composition and physical properties of the obtained toner from the surface to the inside can be changed in stages, and the structure of the toner is easily controlled. In this case, a plurality of layers are laminated stepwise on the surface of the core particle, and a structural change or composition gradient is given from the inside to the outside of the toner particle, thereby changing the physical properties. In this case, the shell layer corresponds to all the layers laminated on the surface of the core particle, and the outermost layer is composed of a layer mainly composed of the second binder resin. In the following explanation, explanation will be made on the assumption that the adhesion process is performed only once.

Conditions for attaching the resin particles made of the second binder resin to the core particles are as follows. That is, the heating temperature in the adhesion step is preferably a temperature in the vicinity of the melting point of the first binder resin contained in the core aggregated particles, and specifically, a temperature range within a melting point ± 10 ° C. preferable.
When the heating temperature is equal to or higher than (the melting point of the first binder resin−10 ° C.), the resin particles made of the first binder resin present on the surface of the core particles and the second adhered to the surface of the core aggregated particles. Adhesion with the resin particles made of the binder resin is good, and as a result, the thickness of the formed shell layer becomes uniform.
In addition, when the heating temperature is equal to or lower than (the melting point of the first binder resin + 10 ° C.), the resin particles made of the first binder resin existing on the surface of the core particles and the second attached to the surface of the core particles. Adhesion to the resin particles made of the binder resin is suppressed, and the obtained toner core particles are excellent in particle size / particle size distribution.
The heating time in the attaching step depends on the heating temperature and cannot be defined generally, but it is preferably 5 minutes to 2 hours.

  In the attaching step, the dispersion obtained by additionally adding the second resin particle dispersion to the mixed dispersion in which the core particles are formed may be left standing or gently stirred by a mixer or the like. Also good. The latter case is advantageous in that uniform adhered resin aggregated particles are easily formed.

-Fusion process-
In the fusion process, the adhered resin aggregated particles obtained in the adhesion process are fused by heating. The fusion step is preferably performed at a higher temperature or higher of the glass transition temperatures of the first binder resin and the second binder resin. As the fusion time, a short time is sufficient if the heating temperature is high, and a long time is necessary if the heating temperature is low. That is, the fusion time depends on the temperature of heating and cannot be defined generally, but it is preferably 30 minutes to 10 hours.

When the core particles are core fusion particles, resin particles made of the second binder resin may be attached. In this case, the dispersion containing the core fusion particles is once filtered, and after the water content of the dispersion is controlled to 30% to 50% by weight, the second resin particle dispersion is further added. Thereby, the particle | grains which consist of 2nd binder resin are made to adhere to the surface of a core fusion particle.
When the water content of the dispersion is 30% by weight or more, the adhesion of the particles made of the second binder resin is good, and the release of the core fusion particles of the particles is suppressed. Further, when the water content is 50% by weight or less, stirring is easy, and particles made of the second binder resin are uniformly attached to the surface of the core fusion particles.

  It should be noted that the particles adhered aggregated particles obtained by adhering the particles made of the second binder resin and the fluoropolymer particles to the surface of the core fused particles are mechanically processed by a Henschel mixer or the like after the washing / drying process described later. By applying an appropriate stress, the particles made of the second binder resin attached to the surface of the core fusion particles are fused. Thus, the fusion process may be performed by applying mechanical stress instead of heating in the liquid phase.

-Washing / drying process-
The fused particles obtained through the fusion step are preferably subjected to solid-liquid separation such as filtration, washing, and drying. As a result, a toner in which no external additive is added is obtained.
The solid-liquid separation is not particularly limited, but suction filtration, pressure filtration and the like are preferable from the viewpoint of productivity. The washing is preferably performed with substitution washing with ion-exchanged water from the viewpoint of chargeability. In the drying process, an arbitrary method such as a normal vibration type fluidized drying method, a spray drying method, a freeze drying method, a flash jet method, or the like is employed. The moisture content of the toner particles after drying is preferably adjusted to 1.0% by weight or less, and more preferably adjusted to 0.5% by weight or less.

-Preparation of dispersion-
A known emulsification method is used to prepare the binder resin dispersion, but the obtained particle size distribution is sharp and the phase inversion emulsification is easy to obtain in a volume average particle size range of 0.08 to 0.40 μm. The law is effective.
In the phase inversion emulsification method, the resin is dissolved in an organic solvent for dissolving the resin, an amphiphilic organic solvent alone, or a mixed solvent to obtain an oil phase. A small amount of a basic compound is dropped while stirring the oil phase, and water is dropped little by little while stirring, and water droplets are taken into the oil phase. Next, when the dripping amount of water exceeds a certain amount, the oil phase and the water phase are reversed and the oil phase becomes oil droplets. Thereafter, an aqueous dispersion is obtained through a desolvation step of depressurization.
Here, the amphiphilic organic solvent means a solvent having a solubility in water at 20 ° C. of preferably 5 g / L or more, more preferably 10 g / L or more. When the solubility is 5 g / L or more, the effect of accelerating the aqueous treatment rate is excellent, and the resulting aqueous dispersion is also excellent in storage stability.

Examples of such organic solvents include ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol, n-amyl alcohol, isoamyl alcohol, sec-amyl alcohol, tert-amyl alcohol, 1 -Alcohols such as ethyl-1-propanol, 2-methyl-1-butanol, n-hexanol and cyclohexanol, ketones such as methyl ethyl ketone, methyl isobutyl ketone, ethyl butyl ketone, cyclohexanone and isophorone, ethers such as tetrahydrofuran and dioxane , Ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, sec-butyl acetate, 3-methoxybutyl acetate, methyl propionate, Esters such as ethyl lopionate, diethyl carbonate, dimethyl carbonate, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol ethyl ether acetate, diethylene glycol, diethylene glycol monomethyl ether , Diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, diethylene glycol ethyl ether acetate, propylene glycol, propylene glycol monomethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, propylene group Examples include glycol derivatives such as coal methyl ether acetate and dipropylene glycol monobutyl ether, and 3-methoxy-3-methylbutanol, 3-methoxybutanol, acetonitrile, dimethylformamide, dimethylacetamide, diacetone alcohol, ethyl acetoacetate, etc. Is done.
These solvents may be used alone or in combination of two or more.

Next, regarding the basic compound, in the present embodiment, the polyester resin used as the binder resin is preferably neutralized with the basic compound when dispersed in an aqueous medium. In the present embodiment, the neutralization reaction with the carboxyl group of the polyester resin is the starting force for making aqueous, and the aggregation between particles is prevented by the electric repulsive force between the generated carboxyl anions.
Examples of the basic compound include ammonia and organic amine compounds having a boiling point of 250 ° C. or lower.
Examples of preferred organic amine compounds include triethylamine, N, N-diethylethanolamine, N, N-dimethylethanolamine, aminoethanolamine, N-methyl-N, N-diethanolamine, isopropylamine, iminobispropylamine, ethylamine , Diethylamine, 3-ethoxypropylamine, 3-diethylaminopropylamine, sec-butylamine, propylamine, methylaminopropylamine, dimethylaminopropylamine, methyliminobispropylamine, 3-methoxypropylamine, monoethanolamine, diethanolamine, Examples include triethanolamine, morpholine, N-methylmorpholine, N-ethylmorpholine and the like.

  The basic compound is preferably added in an amount that can be at least partially neutralized according to the carboxyl group contained in the polyester resin, that is, 0.2 to 9.0 times the molar equivalent of the carboxyl group. It is more preferable to add 6 to 2.0 times molar equivalent. If it is 0.2 times equivalent or more, the effect of adding a basic compound is sufficiently obtained, and if it is 9.0 times mole equivalent or less, the hydrophilicity of the oil phase is appropriate and the particle size distribution is narrow. A liquid can be obtained.

The release agent dispersion is formed by dispersing at least a release agent. As described above, the release agent to be dispersed is a release agent in which an organosilicon compound having a siloxane bond is complexed by a melt mixing process in advance.
The release agent is dispersed by a known method. For example, a rotary shearing homogenizer, a media type dispersing machine such as a ball mill, a sand mill, or an attritor, a high-pressure opposed collision type dispersing machine, or the like is preferably used. The release agent may be a ionic surfactant having polarity and dispersed in an aqueous solvent using a homogenizer as described above to prepare a release agent particle dispersion. In this embodiment, a mold release agent may be used individually by 1 type, and may use 2 or more types together. The average particle size of the release agent particles is preferably 1.0 μm or less, and more preferably 0.1 to 0.5 μm.

The colorant dispersion is formed by dispersing at least a colorant.
The colorant is dispersed by a known method. For example, a rotary-type homogenizer, a ball-type mill, a sand mill, an attritor-type media type disperser, a high-pressure counter-collision type disperser, or the like is preferably used. The colorant may be an ionic surfactant having polarity and dispersed in an aqueous solvent using a homogenizer as described above to produce a colorant particle dispersion. A coloring agent may be used individually by 1 type, and may use 2 or more types together. The volume average particle size of the colorant (hereinafter sometimes simply referred to as an average particle size) is preferably 1 μm or less, more preferably 0.5 μm or less, and 0.01 to 0.5 μm. Is particularly preferred.

There is no restriction | limiting in particular as a combination of the resin of the said resin particle, the said mold release agent, and the said coloring agent, According to the objective, it selects and uses suitably suitably.
In the present embodiment, depending on the purpose, at least one of the binder resin dispersion, the release agent dispersion, and the colorant dispersion may include an internal additive, a charge control agent, an inorganic particle, an organic Other components (particles) such as granules, lubricants and abrasives may be dispersed. In that case, other components (particles) may be dispersed in at least one of the binder resin dispersion, the release agent dispersion, and the colorant dispersion, or the resin particle dispersion and the release agent. You may mix the dispersion liquid which disperse | distributes another component (particle | grains) in the liquid mixture formed by mixing a dispersion liquid and a coloring agent dispersion liquid.

Examples of the dispersion medium in the binder resin dispersion, the release agent dispersion, the colorant dispersion, and the other components include an aqueous medium.
As an aqueous medium, water, such as distilled water and ion-exchange water, alcohol, etc. are mentioned, for example. These may be used individually by 1 type and may use 2 or more types together. As a suitable combination, distilled water and ion exchange water are preferably used. The addition of a surfactant is not only advantageous in terms of the stability of each dispersed particle, such as resin particles, colorant particles, and release agent particles, in the aqueous medium, and thus the storage stability of the dispersion, but also in the aggregation process. This is also advantageous from the viewpoint of the stability of the aggregated particles.
In addition, rosin, rosin derivatives, coupling agents, polymer dispersions are added as dispersants to further stabilize the dispersion stability of the colorant in the aqueous medium and lower the energy of the colorant in the toner. Agents and the like.

In the present embodiment, it is preferable to add and mix a surfactant in an aqueous medium in order to improve dispersion stability.
The volume average primary particle size of the particle dispersion thus obtained can be measured, for example, with a laser diffraction particle size distribution measuring device (LA-700, manufactured by Horiba, Ltd.). As a measurement method, a sample in a dispersion is adjusted to have a solid content of about 2 g, and ion exchange water is added thereto to make about 40 ml. This is put into the cell until an appropriate concentration is reached, waits for about 2 minutes, and is measured when the concentration in the cell becomes almost stable. The obtained volume average primary particle size for each channel was accumulated from the smaller volume volume average primary particle size, and the volume average primary particle size was determined when the accumulation reached 50%.

-External addition process-
The method of externally adding inorganic particles such as silica and titania to the surface of the toner base particles is not particularly limited, and a known method is used, for example, a method of attaching by a mechanical method or a chemical method. It is done.

(Electrostatic image developer)
The electrostatic image developing toner of this embodiment is used as an electrostatic image developer.
The electrostatic image developer of the exemplary embodiment is not particularly limited except that it contains the electrostatic image developing toner of the exemplary embodiment, and can take an appropriate component composition depending on the purpose. When used alone, the toner for developing an electrostatic image of this embodiment is prepared as a one-component electrostatic image developer, and when used in combination with a carrier, it is prepared as a two-component electrostatic image developer. .
As a one-component developer, a method in which a charged toner is formed by frictional charging with a developing sleeve or a charging member, and development is performed according to an electrostatic latent image is also applied.

  In the present embodiment, the development method is not particularly defined, but the two-component development method is preferable. Further, the carrier is not particularly defined as long as the above conditions are satisfied. Examples of the carrier core material include magnetic metals such as iron, steel, nickel, and cobalt, alloys of these with manganese, chromium, rare earth, and the like, and Magnetic oxides such as ferrite and magnetite are mentioned, and from the viewpoint of core material surface properties and core material resistance, ferrite, particularly alloys with manganese, lithium, strontium, magnesium and the like are preferably mentioned.

The carrier used in this embodiment is preferably formed by coating the surface of the core material with a resin. There is no restriction | limiting in particular as said resin, According to the objective, it selects suitably. For example, polyolefin resins such as polyethylene and polypropylene; polyvinyl resins and polyvinylidene resins such as polystyrene, acrylic resins, polyacrylonitrile, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl chloride, polyvinyl carbazole, polyvinyl ether and polyvinyl ketone Vinyl chloride-vinyl acetate copolymer; styrene-acrylic acid copolymer; straight silicone resin composed of organosiloxane bond or modified product thereof; polytetrafluoroethylene, polyvinyl fluoride, polyvinylidene fluoride, polychlorotrifluoroethylene, etc. Fluorine resin; Silicone resin; Polyester; Polyurethane; Polycarbonate; Phenol resin; Urea-formaldehyde resin, Melamine tree , Benzoguanamine resins, urea resins, amino resins such as polyamide resins, epoxy resins, per se known resins and the like. These may be used individually by 1 type and may use 2 or more types together. In the present embodiment, among these resins, it is preferable to use at least a fluorine resin and / or a silicone resin. The use of at least a fluorine-based resin and / or a silicone resin as the resin is advantageous in that the effect of preventing carrier contamination (impaction) due to toner and external additives is high.
In the resin coating, it is preferable that resin particles and / or conductive particles are dispersed in the resin. Examples of the resin particles include thermoplastic resin particles and thermosetting resin particles. Among these, thermosetting resins are preferable from the viewpoint of relatively easily increasing the hardness, and resin particles made of nitrogen-containing resin containing N atoms are preferable from the viewpoint of imparting negative chargeability to the toner. In addition, these resin particles may be used individually by 1 type, and may use 2 or more types together. The average particle size of the resin particles is preferably 0.1 to 2 μm, and more preferably 0.2 to 1 μm. When the average particle size of the resin particles is 0.1 μm or more, the resin particles are excellent in dispersibility in the coating, whereas when the average particle size is 2 μm or less, the resin particles are not easily dropped from the coating.

  Examples of the conductive particles include metal particles such as gold, silver, and copper, carbon black particles, and surfaces of titanium oxide, zinc oxide, barium sulfate, aluminum borate, potassium titanate powder, tin oxide, carbon black, metal And particles covered with the like. These may be used individually by 1 type and may use 2 or more types together. Among these, carbon black particles are preferable in terms of good production stability, cost, conductivity and the like. The type of the carbon black is not particularly limited, but carbon black having a DBP oil absorption of 50 to 250 ml / 100 g is preferable because of excellent production stability. The coating amount of the resin, the resin particles, and the conductive particles on the surface of the core material is preferably 0.5 to 5.0% by weight, and preferably 0.7 to 3.0% by weight. More preferred.

The method for forming the coating is not particularly limited. For example, the resin particles such as crosslinkable resin particles and / or the conductive particles, and a styrene acrylic resin, a fluorine resin, a silicone resin as a matrix resin, etc. And a method of using a film-forming solution containing the above resin in a solvent.
Specifically, the carrier core material is immersed in the film forming liquid, a spray method in which the film forming liquid is sprayed on the surface of the carrier core material, and the carrier core material is floated by flowing air And kneader coater method in which the film forming solution is mixed and the solvent is removed. Among these, the kneader coater method is preferable in the present embodiment.

  The solvent used for the film forming liquid is not particularly limited as long as it can dissolve only the resin as a matrix resin, and is selected from known solvents such as toluene, Aromatic hydrocarbons such as xylene, ketones such as acetone and methyl ethyl ketone, ethers such as tetrahydrofuran and dioxane, and the like. When the resin particles are dispersed in the coating, since the resin particles and the particles as the matrix resin are uniformly dispersed in the thickness direction and the tangential direction of the carrier surface, the carrier is used for a long time. Even when the coating is worn, it is possible to always maintain the same surface formation as when it is not used, and to maintain a good charge imparting ability for the toner over a long period of time. In the case where the conductive particles are dispersed in the coating, the conductive particles and the resin as the matrix resin are uniformly dispersed in the thickness direction and the tangential direction of the carrier surface. Even if the coating is worn out over a long period of time, the same surface formation as when not in use can be maintained, and carrier deterioration is prevented for a long period of time. In addition, when the said resin particle and the said electroconductive particle are disperse | distributed to the said film, the above-mentioned effect is exhibited simultaneously.

The electric resistance of the magnetic carrier formed as described above in the state of a magnetic brush under an electric field of 10 ⁴ V / cm is preferably 10 ⁸ to 10 ¹³ Ωcm. When the electric resistance of the magnetic carrier is 10 ⁸ Ωcm or more, the adhesion of the carrier to the image portion on the image carrier is suppressed, and the brush mark is difficult to appear. On the other hand, when the electrical resistance of the magnetic carrier is 10 ¹³ Ωcm or less, the generation of the edge effect is suppressed and a good image quality is obtained.
The volume resistivity is measured as follows.
A measuring jig that is a pair of 20 cm ² circular electrode plates (made of steel) connected to an electrometer (made by KEITHLEY, trade name: KEITHLEY 610C) and a high-voltage power supply (made by FLUKE, trade name: FLUKE 415B). The sample is placed on the lower electrode plate so as to form a flat layer having a thickness of about 1 mm to 3 mm. Next, after the upper electrode plate is placed on the sample, a 4 kg weight is placed on the upper electrode plate in order to eliminate the gap between the samples. In this state, the thickness of the sample layer is measured. Next, the current value is measured by applying a voltage to the bipolar plate, and the volume resistivity is calculated based on the following equation.
Volume resistivity = applied voltage × 20 ÷ (current value−initial current value) ÷ sample thickness In the above formula, the initial current is the current value when the applied voltage is 0, and the current value indicates the measured current value.

  In the two-component electrostatic charge image developer, the mixing ratio of the toner and the carrier of this embodiment is preferably 2 to 10 parts by weight of the toner with respect to 100 parts by weight of the carrier. Moreover, the preparation method of a developing agent is not specifically limited, For example, the method of mixing with a V blender etc. is mentioned.

(Image forming method)
The electrostatic image developer (electrostatic image developing toner) is used in an image forming method of an electrostatic image developing system (electrophotographic system).
The image forming method of the present embodiment includes a latent image forming step of forming an electrostatic latent image on the surface of the image carrier, and the electrostatic latent image formed on the surface of the image carrier using the electrostatic charge of the present embodiment. A developing process for developing with an image developing toner or developer to form a toner image, a transfer process for transferring the toner image to the surface of the recording medium, and a fixing for fixing the transferred toner image to the recording medium And a process.

  Each of the above steps is a general step per se, and is described in, for example, JP-A-56-40868 and JP-A-49-91231. Note that the image forming method of the present embodiment is carried out by using a known image forming apparatus such as a copying machine or a facsimile machine.

The latent image forming step is a step of forming an electrostatic latent image on the surface of the image carrier.
In the developing step, the electrostatic latent image formed on the surface of the image carrier is developed with the electrostatic image developing toner of the present embodiment or the electrostatic image developer containing the electrostatic image developing toner of the present embodiment. Then, a toner image is formed.
The transfer step is a step of transferring the toner image onto a transfer target.
The fixing step is a step of fixing the toner image by passing the transfer body on which the unfixed toner image is formed between a heating member and a pressure member.

As the heating member used in the fixing step, at least the surface energy of the outermost layer is 30 × 10 ⁻³ N / m or more and 3,000 × 10 ⁻³ N / m or less, and 300 × 10 ⁻³ N / m or more. It is preferably 1,500 × 10 ⁻³ N / m or less.
Thus, the heating member having a high surface energy is preferably formed of a metal material or an inorganic material, and more preferably formed of a metal material.
Examples of the metal material forming the heating member include Fe, Cr, Cu, Ni, Co, Mn, Al, and alloys thereof such as stainless steel, and oxides thereof. Among these, Al and stainless steel are preferable, Al Is more preferable.
Glass, ceramics, etc. are mentioned as an inorganic material which forms a heating member.
In addition, it is preferable that at least the outermost layer of the heating member is formed of the metal material or the inorganic material. For example, the entire heating member may be formed of the metal material or the inorganic material, the outermost layer of the heating member is formed of the metal material or the inorganic material, and a portion other than the outermost layer is formed of another material. It may be.
Examples of the shape of the heating member include a cylindrical roll shape.

In the fixing step, the heating member is heated to a temperature equal to or higher than the melting point of the release agent, and the release agent contained in the toner is melted by the heating member. The temperature of the heating member in the fixing step is preferably 130 to 170 ° C, and more preferably 140 to 160 ° C. Within the above range, the release agent contained in the toner is surely in a molten state.
As described above, the release agent used in the present embodiment contains an organosilicon compound having a siloxane bond, and a contact angle with a heating member in a molten state is 50 ° or less. For this reason, the release agent eluted from the toner spreads to the heating member evenly with high affinity, and the transfer of the release agent to a recording medium such as a sheet on which an image is formed next is reduced. In this way, contamination by the release agent of the feed roll that transports the recording medium after image formation is suppressed, and malfunction during continuous operation is suppressed.

(Image forming device)
The image forming apparatus of the present embodiment includes an image carrier, a charging unit that charges the image carrier, a latent image forming unit that forms an electrostatic latent image on the surface of the image carrier, and a surface on the surface of the image carrier. The formed electrostatic latent image is developed with an electrostatic charge image developing toner or an electrostatic charge image developer containing an electrostatic charge image developing toner to form a toner image, and formed on the surface of the image carrier. Transfer means for transferring the toner image to the surface of the transfer member, and fixing means for fixing the toner image by passing the transfer member on which the unfixed toner image is formed between a heating member and a pressure member. It is characterized by having.

The configuration described in each step of the image forming method is preferably used for the image carrier and each unit.
As each of the above-described means, a well-known means is used in the image forming apparatus. Further, the image forming apparatus used in the present embodiment may include means and devices other than the above-described configuration. Further, the image forming apparatus used in the present embodiment may simultaneously perform a plurality of the above-described means.

(Toner cartridge and process cartridge)
The toner cartridge of this embodiment is a toner cartridge that contains at least the toner for developing an electrostatic charge image of this embodiment. The toner cartridge of this embodiment may contain the electrostatic image developing toner of this embodiment as an electrostatic image developer.
The process cartridge according to the present embodiment includes a developing unit that develops the electrostatic latent image formed on the surface of the image carrier with the electrostatic image developing toner or the electrostatic image developer to form a toner image. And at least one selected from the group consisting of an image carrier, a charging unit for charging the surface of the image carrier, and a cleaning unit for removing the toner remaining on the surface of the image carrier, This is a process cartridge containing at least the electrostatic image developing toner of the present embodiment or the electrostatic image developer of the present embodiment.

The toner cartridge of this embodiment is preferably detachable from the image forming apparatus. That is, in the image forming apparatus having a configuration in which the toner cartridge can be attached and detached, the toner cartridge of the present embodiment in which the toner of the present embodiment is stored is preferably used.
Further, the toner cartridge may be a cartridge that stores toner and a carrier, or a cartridge that stores toner alone and a cartridge that stores a carrier independently.

It is preferable that the process cartridge of the present embodiment is attached to and detached from the image forming apparatus.
In addition, the process cartridge according to the present embodiment may include other members such as a static elimination unit as necessary.
As the toner cartridge and the process cartridge, known configurations may be adopted. For example, Japanese Patent Application Laid-Open Nos. 2008-209489 and 2008-233736 are referred to.

(Example of image forming apparatus)
An example of the image forming apparatus of the present embodiment will be described with reference to FIG. 2, but the present embodiment is not limited at all. FIG. 2 is a schematic cross-sectional view showing an example of the image forming apparatus of the present embodiment.

  In FIG. 2, an automatic document feeder U2 is placed on the upper surface of the platen glass PG at the upper end of the image forming apparatus U1 constituted by a copying machine. The automatic document feeder U2 has a document feed tray TG1 on which a plurality of documents Gi to be copied are stacked. Each of the plurality of documents Gi placed on the document feed tray TG1 is sequentially passed through a copy position on the platen glass PG and discharged to the document discharge tray TG2. The automatic document feeder U2 is rotatable with respect to the image forming apparatus U1 by a hinge shaft (not shown) provided in the rear end portion (−X end portion) extending in the left-right direction, and working the document Gi. When a person puts it on the platen glass PG by hand, it is rotated upward.

  The image forming apparatus U1 has a UI (user interface) through which a user inputs an operation command signal such as a copy start. The document reading apparatus IIT disposed below the transparent platen glass PG on the upper surface of the image forming apparatus U1 includes an exposure system registration sensor (platen registration sensor) Sp disposed at a platen registration position (OPT position) and an exposure optical system A. is doing. The movement and stop of the exposure optical system A are controlled by the detection signal of the exposure system registration sensor Sp, and always stop at the home position. Reflected light from the document Gi passing through the exposure position on the upper surface of the platen glass PG by the automatic document feeder U2 or the document manually placed on the platen glass PG passes through the exposure optical system A and is a solid-state image sensor CCD. Are converted into electrical signals of R (red), G (green), and B (blue).

  The image processing system IPS converts the RGB electrical signals input from the solid-state imaging device CCD into K (black), Y (yellow), M (magenta), and C (cyan) image data and temporarily stores them. Then, the image data is output to the laser drive circuit DL as image data for forming a latent image at a predetermined timing. The laser drive circuit DL outputs a laser drive signal to the latent image forming apparatus ROS according to the input image data. The operations of the image processing system IPS and the laser driving circuit DL are controlled by a controller C constituted by a microcomputer.

  The image carrier PR is rotated in the direction of the arrow Ya. The surface of the image carrier PR is then uniformly charged by a charger (charge roll) CR, and then the laser of the latent image forming apparatus ROS at the latent image writing position Q1. Exposure scanning is performed with the beam L to form an electrostatic latent image. When forming a full-color image, electrostatic latent images corresponding to four color images of K (black), Y (yellow), M (magenta), and C (cyan) are sequentially formed. Only the electrostatic latent image corresponding to the (black) image is formed.

  The surface of the image carrier PR on which the electrostatic latent image is formed rotates and moves sequentially through the development area Q2 and the primary transfer area Q3. The rotary developing device G is a four-color developing device of K (black), Y (yellow), M (magenta), and C (cyan) that sequentially rotates and moves to the developing region Q2 as the rotating shaft Ga rotates. It has GK, GY, GM, and GC. Each of the developing devices GK, GY, GM, GC of each color has a developing roll GR that conveys the developer to the developing region Q2, and an electrostatic latent image on the image carrier PR that passes through the developing region Q2 is displayed. Develop to toner image. The developing containers GK, GY, GM, and GC are configured so that the toner of each color is supplied from the toner supply cartridges mounted in the cartridge mounting portions Hk, Hy, Hm, and Hc (see FIG. 1). Has been. Such a rotary developing device is described in, for example, Japanese Patent Application Laid-Open Nos. 2000-131942 and 2000-231250.

  Below the image carrier PR are a plurality of belt support rolls (Rd, Rt) including an intermediate transfer belt B, a belt drive roll Rd, a tension roll Rt, a walking roll Rw, an idler roll (free roll) Rf, and a backup roll T2a. , Rw, Rf, T2a), a primary transfer roll T1, and a belt frame (not shown) for supporting them. The intermediate transfer belt B is rotatably supported by the belt support rolls (Rd, Rt, Rw, Rf, T2a), and rotates in the arrow Yb direction when the image forming apparatus is in operation.

  When forming a full-color image, an electrostatic latent image of the first color is formed at the latent image writing position Q1, and a toner image Tn of the first color is formed in the development region Q2. The toner image Tn is electrostatically primarily transferred onto the intermediate transfer belt B by the primary transfer roll T1 when passing through the primary transfer region Q3. Thereafter, similarly, the second, third, and fourth color toner images Tn are sequentially superimposed on the intermediate transfer belt B carrying the first color toner image Tn, and finally transferred to a full color. Are formed on the intermediate transfer belt B. In the case of forming a monochromatic monochromatic image, only one developing device is used, and the monochromatic toner image is primarily transferred onto the intermediate transfer belt B. After the primary transfer, the residual toner on the surface of the image carrier PR is neutralized by the static eliminator JR and cleaned by the image carrier cleaner CL1.

  Below the backup roll T2a, a secondary transfer roll T2b is disposed so as to be movable between a position separated from the backup roll T2a and a position in contact therewith. The backup roll T2a and the secondary transfer roll T2b constitute a secondary transfer device T2. A secondary transfer region Q4 is formed by a contact region between the backup roll T2a and the secondary transfer roll T2b. A secondary transfer voltage having a polarity opposite to the charging polarity of the toner used in the developing device G is supplied from the power supply circuit E to the secondary transfer roll T2b, and the power supply circuit E is controlled by the controller C.

  The recording sheet S accommodated in the paper feed tray TR1 or TR2 is taken out by the pick-up roll Rp at a predetermined timing, separated one by one by the separation roll Rs, and registered by the plurality of transport rolls Ra in the paper feed path SH1. It is conveyed to. The recording sheet S conveyed to the registration roll Rr is subjected to the secondary transfer from the pre-transfer sheet guide SG1 in time with the primary transferred multiple toner image or single color toner image moving to the secondary transfer region Q4. Transported to region Q4. In the secondary transfer area Q4, the secondary transfer unit T2 electrostatically secondary-transfers the toner image on the intermediate transfer belt B onto the recording sheet S. The residual toner is removed from the intermediate transfer belt B after the secondary transfer by the belt cleaner CL2. A toner image forming apparatus that forms a toner image by transferring the toner image onto the recording sheet S by the image carrier PR, the charging roll CR, the developing device G, the primary transfer roll T1, the intermediate transfer belt B, the secondary transfer device T2, and the like. PR + CR + G + T1 + B + T2).

  The secondary transfer roll T2b and the belt cleaner CL2 are disposed so as to be freely separated from (contacted with and separated from) the intermediate transfer belt B. When a color image is formed, an unfixed toner image of the final color is formed. Is separated from the intermediate transfer belt B until it is primarily transferred to the intermediate transfer belt B. The secondary transfer roll cleaner CL3 moves away from and in contact with the intermediate transfer belt B together with the secondary transfer roll T2b. The recording sheet S on which the toner image is secondarily transferred is conveyed to the fixing region Q5 by the post-transfer sheet guide SG2 and the sheet conveying belt BH. The fixing region Q5 is a region (nip) where the heating roll Fh and the pressure roll Fp of the fixing device F are in pressure contact, and the recording sheet S passing through the fixing region Q5 is heated and fixed by the fixing device F. The heating roll Fh is formed of, for example, a metal material.

  In FIG. 2, on the downstream side of the fixing region Q5 for fixing the toner image on the recording sheet S, a sheet conveying roll 16 having a driving roll 16a and a driven roll 16b, and a sheet conveying roll having a driving roll Rb1 and a driven roll Rb2. Rb and the sheet discharge path SH2 are sequentially provided. A sheet inversion path SH3 is connected to the sheet discharge path SH2. A switching gate GT1 is provided at a branch point of the sheet discharge path SH2 and the sheet reversal path SH3. The recording sheet S conveyed to the sheet discharge path SH2 is conveyed to the sheet discharge roll Rh by a plurality of conveyance rolls Ra, and is discharged from the sheet discharge port Ka formed at the upper end portion of the image forming apparatus U1 to the discharge tray TR3. The A sheet circulation path SH4 is connected to the sheet reversing path SH3, and a mylar gate GT2 formed of a sheet-like member is provided at the connection portion. The Mylar gate GT2 passes the recording sheet S conveyed through the sheet reversing path SH3 from the switching gate GT1 as it is, and the recording sheet S that has been once switched and switched back to the sheet circulation path SH4 side. Let go. The recording sheet S conveyed to the sheet circulation path SH4 is retransmitted to the transfer area Q4 through the sheet feeding path SH1. A sheet conveying path SH is constituted by the elements indicated by the symbols SH1 to SH4. A sheet conveying apparatus US is configured by the sheet conveying path SH and rolls Ra, Rh and the like having a sheet conveying function arranged there.

  Hereinafter, although this embodiment is described in detail with examples, this embodiment is not limited in any way. In the following description, “parts” means “parts by weight” unless otherwise specified.

<Synthesis of polyester as binder resin>
-Preparation of polyester resin (1)-
-Bisphenol A ethylene oxide 2-mole adduct: 114 parts-Bisphenol A propylene oxide 2-mole adduct: 84 parts-Dimethyl terephthalate: 75 parts-Dodecenyl succinic acid: 19.5 parts-Trimellitic acid: 7.5 parts The above components were put into a 5 liter flask equipped with an apparatus, a nitrogen inlet tube, a temperature sensor, and a rectifying column. The temperature was raised to 190 ° C. over 1 hour, and the reaction system was stirred, and then dibutyl 3.0 parts of tin oxide was added. Further, 6 hours were required while distilling off the generated water, the temperature was raised from 190 ° C. to 240 ° C., and the dehydration condensation reaction was continued at 240 ° C. for another 2 hours to synthesize polyester resin (1).
The obtained polyester resin (1) had a glass transition temperature of 54 ° C., an acid value of 15.3 mgKOH / g, a weight average molecular weight of 58,000, and a number average molecular weight of 5,600.

-Preparation of polyester resin (2)-
-Bisphenol A ethylene oxide 2-mole adduct: 114 parts-Bisphenol A propylene oxide 2-mole adduct: 84 parts-Dimethyl terephthalate: 45 parts-Tetrafluoroterephthalic acid: 25 parts-Dodecenyl succinic acid: 19.5 parts-Tri Merit acid: 7.5 parts The above components were placed in a 5 liter flask equipped with a stirrer, nitrogen inlet tube, temperature sensor, and rectifying column, and the temperature was raised to 190 ° C over 1 hour. After stirring the system, 3.0 parts of dibutyltin oxide was added. Further, 6 hours were required while distilling off the generated water, the temperature was raised from 190 ° C. to 240 ° C., and the dehydration condensation reaction was continued at 240 ° C. for another 5 hours to synthesize polyester resin (2).
The obtained polyester resin (2) had a glass transition temperature of 60 ° C., an acid value of 15.7 mgKOH / g, a weight average molecular weight of 110,000, and a number average molecular weight of 8,000.

<Preparation of polyester resin dispersion>
-Preparation of polyester resin dispersion (1)-
-Polyester resin (1): 160 parts-Ethyl acetate: 233 parts-Sodium hydroxide aqueous solution (0.3N): 0.1 part The above ingredients are placed in a 1,000 ml separable flask and heated at 70 ° C to give three one A resin mixed solution was prepared by stirring with a motor (manufactured by Shinto Kagaku Co., Ltd.). While further stirring this resin mixture, 373 parts of ion-exchanged water was gradually added to effect phase inversion emulsification, and the solvent was removed to obtain a polyester resin dispersion (1) (solid content concentration: 30%). The volume average particle size of the resin particles in the dispersion was 160 nm.

-Preparation of polyester resin dispersion (2)-
・ Polyester resin (2): 160 parts ・ Ethyl acetate: 160 parts ・ Sodium hydroxide aqueous solution (0.3N): 0.1 part The above ingredients were placed in a 1,000 ml separable flask and heated at 70 ° C. A resin mixed solution was prepared by stirring with a motor (manufactured by Shinto Kagaku Co., Ltd.). While further stirring this resin mixture, 373 parts of ion-exchanged water was gradually added to effect phase inversion emulsification and solvent removal to obtain a polyester resin dispersion (2) (solid content concentration: 30%). The volume average particle size of the resin particles in the dispersion was 310 nm.

-Preparation of polyester resin dispersion (3)-
-Polyester resin (2): 160 parts-Ethyl acetate: 120 parts-Sodium hydroxide aqueous solution (0.3N): 0.1 part The above ingredients are put in a 1,000 ml separable flask and heated at 70 ° C, and three-one A resin mixed solution was prepared by stirring with a motor (manufactured by Shinto Kagaku Co., Ltd.). While further stirring this resin mixture, 373 parts of ion-exchanged water was gradually added to effect phase inversion emulsification and solvent removal to obtain a polyester resin dispersion (3) (solid content concentration: 30%). The volume average particle size of the resin particles in the dispersion was 460 nm.

-Preparation of polyester resin dispersion (4)-
-Polyester resin (2): 160 parts-Ethyl acetate: 240 parts-Sodium hydroxide aqueous solution (0.3N): 0.1 part The above ingredients are placed in a 1,000 ml separable flask and heated at 70 ° C to give a three-one. A resin mixed solution was prepared by stirring with a motor (manufactured by Shinto Kagaku Co., Ltd.). While further stirring this resin mixture, 373 parts of ion-exchanged water was gradually added to effect phase inversion emulsification and solvent removal to obtain a polyester resin dispersion (4) (solid content concentration: 30%). The volume average particle size of the resin particles in the dispersion was 160 nm.

-Preparation of polyester resin dispersion (5)-
・ Polyester resin (2): 160 parts ・ Ethyl acetate: 90 parts ・ Sodium hydroxide aqueous solution (0.3N): 0.1 part The above ingredients were placed in a 1,000 ml separable flask and heated at 70 ° C. A resin mixed solution was prepared by stirring with a motor (manufactured by Shinto Kagaku Co., Ltd.). While further stirring this resin mixture, 373 parts of ion-exchanged water was gradually added, phase-inversion emulsified, and the solvent was removed to obtain a polyester resin dispersion (5) (solid content concentration: 30%). The volume average particle size of the resin particles in the dispersion was 510 nm.

-Preparation of polyester resin dispersion (6)-
・ Polyester resin (2): 160 parts ・ Ethyl acetate: 300 parts ・ Sodium hydroxide aqueous solution (0.3 N): 0.1 part The above ingredients were placed in a 1,000 ml separable flask and heated at 70 ° C. A resin mixed solution was prepared by stirring with a motor (manufactured by Shinto Kagaku Co., Ltd.). While further stirring this resin mixture, 373 parts of ion-exchanged water was gradually added to effect phase inversion emulsification and solvent removal to obtain a polyester resin dispersion (6) (solid content concentration: 30%). The volume average particle size of the resin particles in the dispersion was 130 nm.

<Preparation of styrene-acrylic resin particle dispersion>
-Preparation of Styrene-Acrylic Resin Particle Dispersion (1)-
-Styrene: 308 parts-n-Butyl acrylate: 100 parts-Acrylic acid: 4 parts-Dodecanethiol: 8 parts-Propanediol acrylate: 1.5 parts The above ingredients are mixed and dissolved, while the anionic surfactant Dow A solution prepared by dissolving 4 parts of a fax machine (manufactured by Dow Chemical Co., Ltd.) in 550 parts of ion-exchanged water is placed in a flask, dispersed and emulsified by adding the above mixed solution, and slowly stirred and mixed for 10 minutes. Then, 50 parts of an ion exchange aqueous solution in which 6 parts of ammonium persulfate was dissolved was added.
Next, after sufficiently replacing the inside of the system with nitrogen, the flask was heated with an oil bath while stirring until the inside of the system reached 75 ° C. to carry out emulsion polymerization.
As a result, a styrene-acrylic resin particle dispersion (1) (solid content concentration: 42%) having a central particle diameter (volume average particle diameter) of 178 nm, a glass transition temperature of 52 ° C., and a weight average molecular weight Mw of 24,000 is obtained. It was.

-Preparation of large particle size styrene-acrylic resin particle dispersion (2)-
-Styrene: 100 parts-n-butyl acrylate: 208 parts-Trifluoroethyl methacrylate: 32 parts-Acrylic acid: 4 parts-Dodecanethiol: 3 parts-Propanediol acrylate: 1.5 parts The above ingredients are mixed and dissolved. On the other hand, a solution obtained by dissolving 2 parts of the anionic surfactant Dowfax (manufactured by Dow Chemical Co., Ltd.) in 550 parts of ion-exchanged water is placed in a flask, and the above mixed solution is added to disperse and emulsify. While slowly stirring and mixing for 10 minutes, 50 parts of an ion exchange aqueous solution in which 6 parts of ammonium persulfate was dissolved was added.
Next, after sufficiently replacing the inside of the system with nitrogen, the flask was heated with an oil bath while stirring until the inside of the system reached 70 ° C. to carry out emulsion polymerization.
Thus, a large particle size styrene-acrylic resin particle dispersion (2) (solid content concentration: 42%) having a central particle size (volume average particle size) of 335 nm, a glass transition temperature of 52 ° C., and a weight average molecular weight Mw of 65,000. )

-Preparation of Large Particle Size Styrene-Acrylic Resin Particle Dispersion (3)-
-Styrene: 100 parts-n-butyl acrylate: 208 parts-Trifluoroethyl methacrylate: 32 parts-Acrylic acid: 4 parts-Dodecanethiol: 3 parts-Propanediol acrylate: 1.5 parts The above ingredients are mixed and dissolved. On the other hand, a solution obtained by dissolving 2 parts of the anionic surfactant Dowfax (manufactured by Dow Chemical Co., Ltd.) in 550 parts of ion-exchanged water is placed in a flask, and the above mixed solution is added to disperse and emulsify. While slowly stirring and mixing for 10 minutes, 50 parts of an ion exchange aqueous solution in which 6 parts of ammonium persulfate was dissolved was added.
Next, after sufficiently replacing the inside of the system with nitrogen, the flask was heated with an oil bath while stirring until the inside of the system reached 65 ° C. to carry out emulsion polymerization.
Thus, a large-diameter styrene-acrylic resin particle dispersion (3) having a center particle diameter (volume average particle diameter) of 470 nm, a glass transition temperature of 52 ° C., and a weight average molecular weight Mw of 60,000 (solid content concentration: 42%). Got.

-Preparation of Large Particle Size Styrene-Acrylic Resin Particle Dispersion (4)-
・ Styrene 100 parts ・ N-butyl acrylate 208 parts ・ Trifluoroethyl methacrylate 32 parts ・ Acrylic acid 4 parts ・ Dodecanethiol 3 parts ・ Propanediol acrylate 1.5 parts The above ingredients are mixed and dissolved, while the anionic interface A solution obtained by dissolving 2 parts of the activator Dowfax (manufactured by Dow Chemical Co., Ltd.) in 550 parts of ion-exchanged water is placed in a flask, dispersed and emulsified by adding the above mixed solution, and slowly stirred for 10 minutes. -While mixing, 50 parts of an ion exchange aqueous solution in which 6 parts of ammonium persulfate was dissolved was added.
Next, after sufficiently replacing the inside of the system with nitrogen, the flask was heated with an oil bath while stirring until the inside of the system reached 75 ° C. to carry out emulsion polymerization.
Thus, a large particle size styrene-acrylic resin particle dispersion (4) (solid content concentration: 42%) having a central particle size (volume average particle size) of 210 nm, a glass transition temperature of 52 ° C., and a weight average molecular weight Mw of 70,000. )

<Preparation of pigment dispersion>
-Cyan pigment dispersion-
-Cyan pigment (Pigment Blue 15: 3, manufactured by Dainichi Seika Kogyo Co., Ltd.): 30 parts-Anionic activator (Neogen RK, 20% by mass): 3 parts-Ion-exchanged water: 70 parts The above mixture is homogenizer (manufactured by IKA) After dispersion at 5,000 rpm for 5 minutes using an ultra turrax T50), the mixture is stirred for a whole day and night with a stirrer to defoam, and then the dispersion is dispersed into a high-pressure impact dispersion ultimateizer (manufactured by Sugino Machine Co., Ltd., HJP30006). ) To obtain a cyan pigment dispersion (solid content concentration: 20%). The volume average particle size of the pigment particles in the dispersion was 153 nm.

<Preparation of release agent dispersion>
POLYWAX655 (manufactured by Baker Petrolite): 25 parts Anionic activator (Neogen RK, 20% by mass): 2.0 parts Ion-exchanged water: 100 parts The above mixture is heated to 110 ° C. with a high-pressure homogenizer. A release agent dispersion (solid content concentration: 20%) was obtained by treatment at 50 MPa and rapid cooling. The volume average particle size of the release agent particles in the dispersion was 230 nm.

<Example 1>
Toner (1) was prepared as follows.
-Core composition-
-Ion exchange water: 600 parts-Polyester resin dispersion (1): 366 parts-Cyan pigment dispersion: 50 parts-Release agent dispersion: 100 parts-Anionic surfactant: 3.0 parts (Daiichi Kogyo) Pharmaceutical Co., Ltd .: Neogen RK, 20% by mass)
-Shell composition (1)-
-Polyester resin dispersion (1): 100 parts-Anionic surfactant: 3.0 parts (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK, 20% by mass)
-Shell composition (2)-
-Polyester resin dispersion (2): 100 parts-Anionic surfactant: 3.0 parts (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK, 20% by mass)

The core composition was put into a 3 liter reaction vessel equipped with a thermometer, pH meter, and stirrer, and maintained at a temperature of 30 ° C. and a stirring rotation speed of 150 rpm for 30 minutes while controlling the temperature with a mantle heater from the outside.
A PAC aqueous solution in which 1.0 part of PAC (manufactured by Oji Paper Co., Ltd .: 30% powder product) 1.0 part was dissolved in 10 parts of ion-exchanged water while being dispersed with a homogenizer (IKA Japan Co., Ltd .: Ultra Tarax T50). Added. Thereafter, a 0.3N aqueous nitric acid solution was added to adjust the pH in the aggregation process to 3.5. The temperature was raised to 50 ° C., the particle size was measured with Coulter Multisizer II (aperture diameter: 50 μm, manufactured by Coulter), and the volume average particle size was 5.0 μm. The pH was then dropped to 2.5.
Next, the shell composition (1) whose pH is adjusted to 2.5 is additionally added, and after 5 minutes, the shell composition (2) whose pH is further adjusted to 4.3 is further added, and resin particles are added to the surface of the aggregated particles. Adhered (shell structure).
Subsequently, 40 parts of 10% by mass of NTA (nitrilotriacetic acid) metal salt aqueous solution (Cyrest 70: manufactured by Cylest Co., Ltd.) was added, and then the pH was adjusted to 9.0 using 1N aqueous sodium hydroxide solution. Thereafter, the temperature was increased to 90 ° C. at a rate of temperature increase of 0.05 ° C./min, held at 90 ° C. for 3 hours, then cooled and filtered to obtain coarse toner particles. This was further re-dispersed with ion-exchanged water and filtered, and washed until the electrical conductivity of the filtrate was 20 μS / cm or less, and then vacuum-dried in an oven at 40 ° C. for 5 hours. Thus, toner particles were obtained.
To 100 parts of the obtained toner particles, 1.5 parts of hydrophobic silica (manufactured by Nippon Aerosil Co., Ltd., RY50) and 1.0 part of hydrophobic titanium oxide (manufactured by Nippon Aerosil Co., Ltd., T805) And blended for 30 seconds at 10,000 rpm using a sample mill. Thereafter, the toner (1) was prepared by sieving with a vibration sieve having an opening of 45 μm. The obtained toner (1) had a volume average particle diameter of 5.7 μm.

<Example 2>
A toner (2) was prepared in the same manner as in Example 1 except that the polyester resin dispersion (3) was used instead of the polyester resin dispersion (2) used as the adhered particle composition in Example 1. The obtained toner (2) had a volume average particle diameter of 5.8 μm.

<Example 3>
A toner (3) was prepared in the same manner as in Example 1 except that the polyester resin dispersion (4) was used instead of the polyester resin dispersion (2) used as the adhered particle composition in Example 1. The toner (3) obtained had a volume average particle diameter of 5.8 μm.

<Example 4>
In Example 1, the polyester resin dispersion (1) used as the adherent particle shell composition was changed to 70 parts, and the polyester resin dispersion (2) used as the adherent particle composition was similarly changed to 130 parts. A toner (4) was prepared in the same manner as in Example 1 except for the above. The obtained toner (4) had a volume average particle diameter of 5.9 μm.

<Example 5>
In Example 2, the polyester resin dispersion (1) used as the adherent particle shell composition was changed to 70 parts, and the polyester resin dispersion (3) used as the adherent particle composition was similarly changed to 130 parts. A toner (5) was prepared in the same manner as in Example 2 except for the above. The obtained toner (5) had a volume average particle diameter of 6.0 μm.

<Example 6>
In Example 3, the polyester resin dispersion (1) used as the shell composition for adhered particles was changed to 70 parts, and the polyester resin dispersion (4) used as the adhered particle composition was similarly changed to 130 parts. A toner (6) was prepared in the same manner as in Example 3 except for the above. The volume average particle diameter of the obtained toner (6) was 5.9 μm.

<Example 7>
In Example 1, the polyester resin dispersion (1) used as the adherent particle shell composition was changed to 130 parts, and the polyester resin dispersion (2) used as the adherent particle composition was changed to 70 parts. A toner (7) was prepared in the same manner as in Example 1 except for the above. The obtained toner (7) had a volume average particle diameter of 5.7 μm.

<Example 8>
In Example 2, the polyester resin dispersion (1) used as the shell composition for adhered particles was changed to 130 parts, and the polyester resin dispersion (3) used as the adhered particle composition was similarly changed to 70 parts. A toner (8) was prepared in the same manner as in Example 2 except for the above. The obtained toner (8) had a volume average particle diameter of 5.7 μm.

<Example 9>
In Example 2, the polyester resin dispersion (1) used as the shell composition for adhered particles was changed to 130 parts, and the polyester resin dispersion (4) used as the adhered particle composition was similarly changed to 70 parts. A toner (9) was prepared in the same manner as in Example 3 except for the above. The volume average particle diameter of the obtained toner (9) was 5.6 μm.

<Example 10>
A toner (10) was prepared in the same manner as in Example 1 except that the polyester resin dispersion (4) was used instead of the polyester resin dispersion (2) used as the adhered particle composition in Example 1. The volume average particle diameter of the obtained toner (10) was 5.8 μm.

<Example 11>
Toner (11) )created. The volume average particle diameter of the obtained toner (11) was 5.5 μm.

<Example 12>
-Styrene-acrylic resin particle dispersion (1): 187 parts-Colorant particle dispersion: 42.7 parts-Release agent particle dispersion: 60.0 parts-Polyaluminum chloride (10% aqueous solution): 2.4 Parts / ion exchange water: 375 parts After thoroughly mixing and dispersing the above components in a round stainless steel flask using a homogenizer (IKA Japan Co., Ltd .: Ultra Tarax T50), the flask was heated with an oil bath for heating. Heat to 52 ° C. with stirring. After maintaining the volume average particle size at 4.9 μm by maintaining at 52 ° C. (initial heating temperature), 46 parts of styrene-acrylic resin particle dispersion (1) adjusted to pH 2.5 was gradually added thereto, and pH 4 was further increased. 46 parts of a large particle size styrene-acrylic resin particle dispersion (2) adjusted to .5 were added.
Then, after adjusting the pH in the system to 6.5 using a 0.5 mol / L sodium hydroxide aqueous solution, the stainless steel flask was sealed, and the stirring shaft seal was magnetically sealed while continuing stirring. Heated to 97 ° C. After completion of the reaction, the reaction mixture was cooled, filtered, thoroughly washed with ion exchange water, and solid-liquid separation was performed by Nutsche suction filtration. This was further redispersed with 3 L of ion exchanged water at 40 ° C., and stirred and washed at 300 rpm for 15 minutes. This washing operation was further repeated 5 times, and No. 3 was obtained by Nutsche suction filtration. Solid-liquid separation was performed using 5A filter paper. Next, vacuum drying was continued for 12 hours to obtain a toner (12).
The volume average particle diameter of the toner particles at this time was measured and found to be 5.8 μm.

<Example 13>
Example 12 is the same as Example 12 except that the large particle size styrene-acrylic resin particle dispersion (3) was used instead of the large particle size styrene-acrylic resin particle dispersion (2) used as the adhered particle composition in Example 10. In the same manner, Toner (13) was prepared. The volume average particle diameter of the obtained toner (13) was 5.8 μm.

<Example 14>
Example 12 and Example 12 except that the large particle size styrene-acrylic resin particle dispersion (4) was used instead of the large particle size styrene-acrylic resin particle dispersion (2) used as the adhering particle composition in Example 10. In the same manner, a toner (14) was prepared. The volume average particle diameter of the obtained toner (14) was 5.8 μm.

<Comparative Example 1>
Toner (15) was prepared as follows.
-Core composition-
-Ion exchange water: 600 parts-Polyester resin dispersion (1): 366 parts-Cyan pigment dispersion: 50 parts-Release agent dispersion: 100 parts-Anionic surfactant: 3.0 parts (Daiichi Kogyo) Pharmaceutical Co., Ltd .: Neogen RK, 20% by mass)
-Shell composition (1)-
-Polyester resin dispersion (1) 100 parts-Anionic surfactant: 3.0 parts (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK, 20% by mass)
-Shell composition (2)-
-Polyester resin dispersion (2) 100 parts-Anionic surfactant: 3.0 parts (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK, 20% by mass)

The core composition was put into a 3 liter reaction vessel equipped with a thermometer, pH meter, and stirrer, and maintained at a temperature of 30 ° C. and a stirring rotation speed of 150 rpm for 30 minutes while controlling the temperature with a mantle heater from the outside.
A PAC aqueous solution in which 1.0 part of PAC (manufactured by Oji Paper Co., Ltd .: 30% powder product) 1.0 part was dissolved in 10 parts of ion-exchanged water while being dispersed with a homogenizer (IKA Japan Co., Ltd .: Ultra Tarax T50). Added. Thereafter, a 0.3N aqueous nitric acid solution was added to adjust the pH in the aggregation process to 3.5. The temperature was raised to 50 ° C., the particle size was measured with Coulter Multisizer II (aperture diameter: 50 μm, manufactured by Coulter), and the volume average particle size was 5.0 μm. The pH was then dropped to 2.5.
Next, the shell compositions (1) and (2) adjusted to pH 3.8 were additionally added, and the resin particles were adhered to the surface of the aggregated particles (shell structure).
Subsequently, 40 parts of 10% by mass of NTA (nitrilotriacetic acid) metal salt aqueous solution (Cyrest 70: manufactured by Cylest Co., Ltd.) was added, and then the pH was adjusted to 9.0 using 1N aqueous sodium hydroxide solution. Thereafter, the temperature was increased to 90 ° C. at a rate of temperature increase of 0.05 ° C./min, held at 90 ° C. for 3 hours, then cooled and filtered to obtain coarse toner particles. This was further re-dispersed with ion-exchanged water and filtered, and washed until the electrical conductivity of the filtrate was 20 μS / cm or less, and then vacuum-dried in an oven at 40 ° C. for 5 hours. Thus, toner particles were obtained.
To 100 parts of the obtained toner particles, 1.5 parts of hydrophobic silica (manufactured by Nippon Aerosil Co., Ltd., RY50) and 1.0 part of hydrophobic titanium oxide (manufactured by Nippon Aerosil Co., Ltd., T805) And blended for 30 seconds at 10,000 rpm using a sample mill. Thereafter, the toner (15) was prepared by sieving with a vibrating sieve having an opening of 45 μm. The volume average particle size of the obtained toner (15) was 6.0 μm.

<Comparative example 2>
In Example 1, the polyester resin dispersion (1) used as the shell composition for adhered particles was changed to 20 parts, and the polyester resin dispersion (3) used as the adhered particle composition was similarly changed to 180 parts. A toner (16) was prepared in the same manner as in Example 1 except for the above. The volume average particle size of the obtained toner (16) was 6.1 μm.

<Comparative Example 3>
In Example 1, the polyester resin dispersion (1) used as the adherent particle shell composition was changed to 180 parts, and the polyester resin dispersion (3) used as the adherent particle composition was similarly changed to 20 parts. A toner (17) was prepared in the same manner as in Example 1 except for the above. The volume average particle diameter of the obtained toner (17) was 6.1 μm.

<Comparative example 4>
-Styrene-acrylic resin particle dispersion (1): 187 parts-Colorant particle dispersion: 42.7 parts-Release agent particle dispersion: 60.0 parts-Polyaluminum chloride (10% aqueous solution): 2.4 Parts / ion-exchanged water: 375 parts The above ingredients were thoroughly mixed and dispersed in a round stainless steel flask using a homogenizer (IKA Japan Co., Ltd .: Ultra Tarax T50). Heat to 52 ° C. with stirring. Styrene-acrylic resin particle dispersion (1) and large particle size styrene-acrylic resin particles having a volume average particle size of 4.9 μm held at 52 ° C. (initial heating temperature) and then adjusted to pH 3.8 The dispersion liquid (2) was further added, and resin particles were adhered (shell structure) to the surface of the aggregated particles.
Then, after adjusting the pH in the system to 6.5 using a 0.5 mol / L sodium hydroxide aqueous solution, the stainless steel flask was sealed, and the stirring shaft seal was magnetically sealed while continuing stirring. Heated to 97 ° C. After completion of the reaction, the reaction mixture was cooled, filtered, thoroughly washed with ion exchange water, and solid-liquid separation was performed by Nutsche suction filtration. This was further redispersed with 3 L of ion exchanged water at 40 ° C., and stirred and washed at 300 rpm for 15 minutes. This washing operation was further repeated 5 times, and No. 3 was obtained by Nutsche suction filtration. Solid-liquid separation was performed using 5A filter paper. Next, vacuum drying was continued for 12 hours to prepare toner (18). The volume average particle size of the obtained toner (18) was measured and found to be 5.7 μm.

<Conditions for removing external additives>
Ultrasonic vibration (output 20 W, frequency 20 kHz) is allowed to act on a dispersion in which toner is dispersed in a Triton solution (polyoxyethylene octyl phenyl ether (0.2% by weight aqueous solution manufactured by Wako Pure Chemical Industries, Ltd.)) for 5 minutes. Thereafter, filtration was performed to obtain toner mother particles from which the external additive had been removed.

<Evaluation method of transfer efficiency>
The developer obtained in the environment room at room temperature 28 ° C. and humidity 90% is converted into a four-drum tandem-type Fuji Xerox Co., Ltd. DocuCenter Color 450a remodeling machine (the process speed of the fixing device is controlled by an external power supply). The developer is adjusted so that it is controlled by the control), and the toner is adjusted to a toner paper amount of 6 g / m ² at 10 cm on the tip of the image on Fuji Xerox Co., Ltd. color paper (J paper). Continuous 10,000 images were formed at a peripheral speed of 2,000 mm / sec. After the passage of 10,000 sheets, a solid batch of 5 cm × 2 cm was developed, and the developed toner image on the surface of the photoreceptor was transferred using the adhesiveness of the tape surface, and the weight (W1) was measured. Similarly, the degree of unevenness was visually evaluated on the developed toner image on the surface of the photoreceptor on which the solid batch was developed. Next, the same developed toner image was transferred to the surface of paper (J paper: manufactured by Fuji Xerox Office Supply Co., Ltd.), and the weight (W2) of the transferred image was measured. From these, the transfer efficiency was determined by the following formula, and the transferability was evaluated.
Transfer efficiency (%) = (W2 / W1) × 100

-Evaluation criteria for transferability (transfer efficiency)-
G5: Transfer efficiency is 96% or more G4: Transfer efficiency is 93% or more and less than 96% G3: Transfer efficiency is 90% or more and less than 93% G2: Transfer efficiency is 85% or more and less than 90% G1: Transfer efficiency is less than 85%

<Evaluation method for cleaning properties>
Every time 2,000 images were formed, the deposits on the photoreceptor were visually confirmed and evaluated according to the following criteria.
-Evaluation criteria for cleaning-
G5: No deposits can be confirmed on the photoconductor up to 10,000 sheets.
G4: No deposits can be confirmed on the photoconductor up to 6,000 sheets.
G3: No deposits can be confirmed on the photoconductor up to 4,000 sheets.
G2: At the time when 4,000 images are formed, streaky deposits are confirmed. However, there is no practical problem.
G1: At the time when 4,000 sheets of images are formed, there are deposits on almost the entire area of the photoreceptor.
It is allowable up to G2.

<Measurement method of uneven circumference meter>
Using toner S4800 (scanning electron microscope: manufactured by Hitachi High-Technologies Corporation) as a toner base particle, the entire toner can be observed, and a toner image is obtained at a magnification of 10,000 times. Next, the entire toner image was subjected to image analysis using LUZEX manufactured by Nireco Corporation, and the peripheral length (S1) of the toner particles was determined. Next, the toner particle diameter D _50v was measured, and the PM value (circumference length) was obtained by the following formula.
PM (circle perimeter) = perimeter (S1) / toner particle diameter D _50v
If this PM value is a perfect circle, it approaches 3.14, which is the circumference ratio. On the other hand, if the PM value is large, it indicates that the unevenness of the toner shape is large.

U1: Image forming apparatus PG: Platen glass U2: Automatic document feeder Gi: Documents TG1, TG2: Tray IIT: Document reader Sp: Exposure system registration sensor A: Exposure optical system CCD: Solid-state imaging device IPS: Image processing system DL: Laser drive circuit ROS: latent image forming device C: controller PR: image carrier CR: charger Q1: latent image writing position Q2: development region Q3: primary transfer region G: rotary developing device Ga: rotating shaft GK , GY, GM, GC: Four-color developing device GR: Developing roll Hk, Hy, Hm, Hc: Cartridge mounting portion B: Intermediate transfer belt Rd: Belt drive roll Rt: Tension roll Rw: Walking roll Rf: Idler roll T2a : Backup roll T1: Primary transfer roll JR: Static eliminator CL1: Image carrier cleaner T2b: Next transfer roll T2: Secondary transfer device Q4: Secondary transfer area E: Power supply circuit S: Recording sheet Rp: Pickup roll Rs: Separation roll SH1: Paper feed path Ra: Transport roll Rr: Registration roll SG1: Pre-transfer sheet guide CL2 : Belt cleaner CL3: secondary transfer roll cleaner SG2: post-transfer sheet guide BH: sheet conveyance belt Q5: fixing area F: fixing device Fh: heating roll Fp: pressure roll 16a: driving roll 16b: driven roll 16: sheet conveyance Roll Rb1: Drive roll Rb2: Driven roll Rb: Sheet transport roll SH2: Sheet discharge path SH3: Sheet reversing path GT1: Switching gate Ra: Transport roll Rh: Sheet discharge roll Ka: Sheet discharge port TR3: Paper discharge tray SH4: Sheet Circuit GT2: Mylar gate SH: Sheet conveyance path US: Sheet conveyance Equipment

Claims (8)

  The toner base particles having fluoropolymer particles attached to the surface of the center particles have a ratio X of the peripheral length (PM) / equivalent circle diameter (D) of 3.6 to 5.0. Toner for developing electrostatic images.   2. The electrostatic image developing toner according to claim 1, wherein a volume average value of particle diameters of the fluoropolymer particles is 150 to 500 nm.   The electrostatic image developing toner according to claim 1, wherein the binder resin of the center particle is a polyester resin or an acrylic resin.   The electrostatic image developing toner according to claim 1, wherein the fluoropolymer particles contain 0.1 to 30 parts by weight of a fluorine compound with respect to 100 parts by weight of the resin.   5. The static according to claim 1, wherein the number average value of the ratio of the projected area of the fluoropolymer particles to the total projected area of the toner base particles by SEM observation is 20 to 80%. Toner for charge image development. An aggregation step of aggregating a dispersion containing at least a binder resin and a colorant to form an aggregate;
A particle attaching step of attaching fluoropolymer particles to the surface of the aggregate;
The method for producing a toner for developing an electrostatic image according to claim 1, further comprising a fusing step of fusing and coalescing the aggregate and the adhering fluoropolymer particles.   A developer comprising the electrostatic image developing toner according to claim 1 and a carrier. A latent image forming step of forming an electrostatic latent image on the surface of the image carrier;
The electrostatic latent image formed on the surface of the image carrier is developed with the electrostatic charge image developing toner according to claim 1 or the developer according to claim 7 to develop a toner image. A development step to form
A transfer step of transferring the toner image to the surface of the recording medium;
A fixing step of fixing the transferred toner image onto a recording medium.

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