JP5347728B2 - Electrostatic image developing toner, electrostatic image developer, toner cartridge, process cartridge, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrostatic charge image developing toner, for forming a halftone image excellent in storage property and durability and suppressing image blur when a sheet having low smoothness is used. <P>SOLUTION: The electrostatic charge image developing toner includes a polyester resin, a release agent, an inorganic meal salt and a compound expressed by structural formula 1, and is characterized in that the tan&delta; of the toner at 140&deg;C at 1 Hz is 0.5 or more and 2.0 or less; and when 0.1 g of the toner is dispersed in 50 mL of 0.5 mol/L NaOH aqueous solution at 28&deg;C to obtain a dispersion liquid, the content of a compound expressed by structural formula 1 included in the dispersion liquid is 1 ppm or more and 1,000 ppm or less. In structural formula 1, A represents a hydrogen atom or an alkali metal atom. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an electrostatic image developing toner, an electrostatic image developer, a toner cartridge, a process cartridge, and an image forming apparatus.

  A method of visualizing image information through an electrostatic charge image such as electrophotography is currently used in various fields. In electrophotography, an electrostatic image is formed on a photoreceptor by charging and exposure processes, the electrostatic image is developed with a developer containing toner, and the toner image is visualized through a transfer and fixing process.

  As the developer used here, a two-component developer containing a toner and a carrier and a one-component developer using a magnetic toner or a non-magnetic toner alone are known.

  By the way, in order to provide a toner for developing an electrostatic image capable of obtaining a full-color image having high gloss and suppressing gloss unevenness and capable of obtaining fine line reproduction, particularly in image formation using cardboard, a binder resin and An electrostatic charge image developing toner containing a colorant, wherein the content of aluminum element relative to carbon is 0.005 atm% or more and less than 0.02 atm% by X-ray photoelectron spectroscopy. Toners are disclosed (for example, see Patent Document 1).

  Further, in order to provide a toner with moderate gloss control, good color development, and excellent low-temperature fixability and hot offset resistance, it contains a binder resin, a pigment, and inorganic fine particles. A toner is disclosed, wherein the inorganic fine particles have an average particle diameter of 0.5 to 5.0 μm and a content of 0.2 to 20% by weight (for example, (See Patent Document 2).

  In addition, in order to provide an electrostatic image developing toner capable of suppressing gloss unevenness and hot offset, an electrostatic image developing toner containing a binder resin, a colorant, and a divalent or higher metal. An electrostatic charge image developing toner is disclosed in which the metal release rate of the bivalent or higher metal is 18% or less and the metal element release rate is 15% or less (for example, , See Patent Document 3).

  Also, a degradable polyester composed of poly α-hydroxycarboxylic acid in order to provide a toner that exhibits good deinking and whiteness in used paper recycling, and has good fixability, grindability, hot offset resistance, and storage stability. An electrophotographic toner using a toner binder resin containing a resin and a polyester resin other than the resin as a main component is disclosed (for example, see Patent Document 4 or 5).

  In addition, in order to provide a toner exhibiting excellent deinkability and whiteness in used paper recycling, in addition to excellent basic performance as a toner such as pulverization property, fixing property, hot offset resistance and storage property, asparagine It contains 3 to 30% by weight of a copolymer having a structural unit of acid and / or glutamic acid and a structural unit of hydroxycarboxylic acid and having a weight average molecular weight of 1,000 to 100,000 and 70 to 97% by weight of a polyester resin. An electrostatic charge developing electrophotographic toner comprising a toner binder resin composition is disclosed (for example, see Patent Document 6).

Japanese Patent Laid-Open No. 2008-20806 JP 2005-308890 A JP 2006-146056 A JP 2002-55491 A JP 2003-323002 A Japanese Patent Laid-Open No. 2004-12934

  An object of the present invention is to provide a toner for developing an electrostatic charge image that forms a halftone image that is excellent in storage stability and durability and suppresses image bleeding when a paper having low smoothness is used. .

That is, the invention according to claim 1 includes a polyester resin, a release agent, an inorganic metal salt, and a compound represented by the following structural formula 1,
Tan δ at 140 ° C. and 1 Hz is 0.5 or more and 2.0 or less,
When 0.1 g of the present toner is dispersed in 50 mL of a 0.5 mol / L NaOH aqueous solution at 28 ° C. to obtain a dispersion, the content of the compound represented by the following structural formula 1 contained in the dispersion is 1 ppm or more. It is a toner for developing an electrostatic charge image that is 1000 ppm or less.

  In Structural Formula 1, A represents a hydrogen atom or an alkali metal atom.

  The invention according to claim 2 is the electrostatic image developing toner according to claim 1, wherein the metal element contained in the inorganic metal salt is Al.

  A third aspect of the present invention is an electrostatic charge image developer containing the electrostatic charge image developing toner according to the first or second aspect.

  According to a fourth aspect of the present invention, there is provided a toner cartridge which contains at least toner and the toner is the electrostatic image developing toner according to the first or second aspect.

  According to a fifth aspect of the present invention, there is provided a process cartridge comprising at least a developer holder and containing the electrostatic charge image developer according to the third aspect.

  The invention according to claim 6 is formed on the photosensitive member, a charging unit that charges the photosensitive member, an electrostatic charge image forming unit that forms an electrostatic charge image on the surface of the charged photosensitive member, and the photosensitive member. A developing unit that develops the electrostatic image as a toner image with the electrostatic image developer according to claim 3, a transfer unit that transfers the toner image onto a transfer target, and a fixing unit that fixes the toner image. And an image forming apparatus.

  According to the first aspect of the present invention, there is obtained an electrostatic charge image developing toner capable of forming a halftone image having excellent storage stability and durability and suppressing image bleeding when using a paper having low smoothness. It is done.

  According to the second aspect of the present invention, image bleeding is further suppressed as compared with the case where the metal element contained in the inorganic metal salt is other than Al.

  According to the third aspect of the invention, there is provided an electrostatic charge image developer capable of forming a halftone image having excellent storage stability and durability and suppressing image bleeding when using a paper having low smoothness. The

  According to the fourth aspect of the present invention, supply of electrostatic charge image developing toner that forms a halftone image that has excellent storage stability and durability and suppresses image bleeding when using a paper having low smoothness. A toner cartridge that facilitates the above is provided.

  According to the invention of claim 5, when a paper having low smoothness is used, the electrostatic charge image developer that forms a halftone image that is excellent in storage stability and durability and suppresses image bleeding is handled. This facilitates the adaptability to various types of image forming apparatuses.

  According to the sixth aspect of the present invention, there is provided an image forming apparatus in which a halftone image which is excellent in storage stability and durability and suppresses image blur when a paper having low smoothness is used is provided.

1 is a schematic configuration diagram illustrating an example of an image forming apparatus according to an exemplary embodiment. It is a schematic block diagram which shows an example of the process cartridge which concerns on this embodiment.

  Hereinafter, embodiments of an electrostatic image developing toner, an electrostatic image developer, a toner cartridge, a process cartridge, and an image forming apparatus according to the present invention will be described in detail.

<Toner for electrostatic image development>
The electrostatic image developing toner according to the exemplary embodiment includes a polyester resin, a release agent, an inorganic metal salt, and a compound represented by the following structural formula 1, and tan δ at 140 ° C. and 1 Hz is 0.5 or more and 2.0. The content of the compound represented by the following structural formula 1 contained in the dispersion when 0.1 g of the present toner is dispersed in 50 mL of 0.5 mol / L NaOH aqueous solution at 28 ° C. The amount is from 1 ppm to 1000 ppm.
Here, the toner is the electrostatic image developing toner according to the present embodiment.

  In Structural Formula 1, A represents a hydrogen atom or an alkali metal atom.

In the present embodiment, tan δ is a value obtained by the following method.
A rheometer manufactured by Rheometrics, Inc., trade name “ARES” (RHIOS system ver. 6.4.4) was used as a measuring apparatus. Using a parallel plate having a diameter of 8 mm, a toner previously melted on a hot plate and molded into a diameter of 8 mm and a thickness of 2 mm was sandwiched between the parallel plates, and measurement was performed by sinusoidal vibration. The frequency was 6.28 rad / s, and the dynamic viscoelasticity was measured while increasing the temperature by 1 ° C. per minute in the range of 30 ° C. to 180 ° C. After setting the initial value to 0.03%, the strain was changed in the automatic measurement mode, and the loss tangent tan δ at 140 ° C. was obtained.

In the present embodiment, 0.1 g of the electrostatic charge image developing toner according to the present embodiment is dispersed in 50 mL of a 0.5 mol / L NaOH aqueous solution at 28 ° C. to obtain a dispersion. The content of the compound represented by Structural Formula 1 included is a value measured by the following method.
(1) Weigh 0.1 g of toner, add an appropriate amount of 50 mL of 0.5 M NaOH aqueous solution and 20% surfactant (Taika Power), and mix and stir using a ball mill at 28 ° C. for 2 hours.
(2) Then, (1) is separated for 30 minutes at 2000 rpm using a centrifuge.
(3) The supernatant obtained in (2) is subjected to solid-liquid separation using JIS standard 5A filter paper.
(4) 8.5 mL of the filtrate obtained in (3), 1.0 mL of acetate buffer solution (a mixture of 20.0 mL of 1M acetic acid, 30.0 mL of 1M sodium acetate, and 100 mL of ion-exchanged water) and 0.19 Weigh 0.5 mL of an aqueous iron (III) chloride solution into an Erlenmeyer flask and mix thoroughly.
(5) Using the high-performance liquid chromatograph (HPLC), the sample obtained in (4) was subjected to measurement of the content of the compound represented by Structural Formula 1 contained in the dispersion under the following conditions.
Analytical apparatus: LaChromElite L-2000 series manufactured by Hitachi High-Technologies Corporation, column: HITACHI GL-W520-S (Φ7.8 mm × 300 mm), detector: L-2455 type diode array detector, measurement wavelength: UV 190-400 nm Quantitative wavelength: UV 284 nm, mobile phase: 50 mM dipotassium hydrogen phosphate, liquid feed rate: 1.0 mL / min, sample injection amount: 10 μL, column temperature: 50 ° C.
Content (ppm) of the compound represented by Structural Formula 1 contained in the dispersion liquid = Detected amount (ppm) of the compound represented by Structural Formula 1 by the HPLC × (50 ÷ 8.5)

According to the toner for developing an electrostatic charge image according to the present embodiment, when a paper having low smoothness is used, a halftone image which is excellent in storage stability and durability and suppresses image bleeding is formed. The reason is not clear, but is presumed as follows.
Since paper with low smoothness has a large gap between paper fibers, toner is buried between paper fibers in an image portion with a small amount of toner such as a halftone image. For this reason, when heat is applied at the time of fixing, the cohesive force between the toners is weak, so that the melted toner flows out along the flow of fibers, and image blurring may occur. Further, the cohesive force between the toners is weak and the toner flows out, so that the durability of the image is low and the storage stability of the image may be inferior.

Since the electrostatic image developing toner according to the exemplary embodiment includes the compound represented by the structural formula 1, the toner and the paper have high affinity. For this reason, the toner does not flow out even when melted at the time of heat fixing, the occurrence of image blur is suppressed, and good graininess is obtained. Further, since the toner strongly adheres to the paper, the durability and storage stability of the image are also improved.
The reason for the high affinity between the electrostatic image developing toner according to this embodiment and the paper is presumed as follows. The electrostatic image developing toner according to the exemplary embodiment includes the compound represented by Structural Formula 1, and the compound has a hydroxyl group in the molecule. On the other hand, the fibers constituting the paper contain cellulose as a main component. Hydroxyl groups are present in cellulose. For this reason, it is presumed that the affinity between the toner for developing an electrostatic charge image according to this embodiment and the paper is high due to the affinity between the hydroxyl group in cellulose and the hydroxyl group in the compound represented by Structural Formula 1.

Usually, when the toner has a crosslinking component, the molecular chain entanglement of the binder resin exists, and the molecular chain entanglement has a great influence on the melt viscosity behavior of the toner. When the toner has a high tan δ, the molecular chains are less entangled and the elasticity is low or the viscosity is high, so that it may be difficult to obtain a low gloss image. On the other hand, if tan δ is excessively low, conversely, the sheet may be wound around the fixing roll due to poor melting or low temperature offset may be caused. If tan δ is high, the molecular chain of the polyester resin, which is the binder resin, is less entangled and the molecular chain motion becomes active, so that the polar group having the function of supplementing the adhesive force between the paper and the toner is localized. As a result, there may be a case where a sufficient adhesive force cannot be obtained between the paper and the toner in a portion having few polar groups. On the other hand, the fixing temperature may increase in a portion where there are many polar groups.
From such a viewpoint, the toner for developing an electrostatic charge image according to the exemplary embodiment needs to have a tan δ at 140 ° C. and 1 Hz of 0.5 or more and 2.0 or less in a toner containing at least an inorganic metal salt. . The tan δ is preferably 0.6 or more and 1.5 or less, and more preferably 0.7 or more and 1.2 or less. If tan δ exceeds 2.0, an offset in the halftone image portion may occur or the image strength may be reduced. On the other hand, if tan δ is less than 0.5, a sheet may be wound around the fixing roll or a low temperature offset may occur due to poor melting.

  In this embodiment, it is contained in the dispersion liquid when 0.1 g of the electrostatic charge image developing toner according to this embodiment is dispersed in 50 mL of 0.5 mol / L NaOH aqueous solution at 28 ° C. The content of the compound represented by Structural Formula 1 must be 1 ppm or more and 1000 ppm or less. 200 ppm to 800 ppm is preferable, and 400 ppm to 600 ppm is more preferable. If the content exceeds 1000 ppm, the amount of OH groups in the toner amount is too high and the hydrophilicity is too high, so that the moisture content of the toner increases, the fixing temperature increases, and the strength of the fixed image decreases. There is. On the other hand, when the content is less than 1 ppm, since the OH group is small relative to the toner amount, the affinity between the toner and the paper is low, and the adhesion strength of the toner to the paper may be low.

Compared with other chelating agents such as EDTA (ethylenediaminetetraacetic acid), EDDS (ethylenediaminedisuccinic acid), and HIDA (hydroxyethyliminodiacetic acid), the compound represented by structural formula 1 is It is assumed that the cross-linked structure is different. The mechanism is unknown, but the different structures are probably due to the different stability constants of the cross-linked structures. The crosslinked structure formed between the polyester resin, the inorganic metal ion, and the compound represented by Structural Formula 1 is presumed to be stronger and more efficiently crosslinked than when other chelating agents are used.
When the inorganic metal ion is Al, the crosslinked structure is stronger. Although the cause is unknown, it is presumed that the stability constant of the cross-linked structure of the polyester resin, Al, Al, and the compound represented by Structural Formula 1 is close.

  The electrostatic image developing toner according to the present embodiment is effective when forming a halftone image on a sheet having low smoothness. In particular, when a paper having a smoothness of Beck smoothness of 1 second or more and 30 seconds or less is used, the effect is remarkable.

Next, each component constituting the electrostatic image developing toner according to the exemplary embodiment will be described.
The toner according to the exemplary embodiment includes a polyester resin, a release agent, an inorganic metal salt, a compound represented by the structural formula 1, and other additives as necessary.

(Polyester resin)
The electrostatic image developing toner according to the exemplary embodiment includes a polyester resin. The polyester resin desirably used in the present embodiment is obtained, for example, by condensation polymerization of polyvalent carboxylic acids and polyhydric alcohols.
Examples of polyvalent carboxylic acids include aromatic carboxylic acids such as terephthalic acid, isophthalic acid, phthalic anhydride, trimellitic anhydride, pyromellitic acid, naphthalene dicarboxylic acid; maleic anhydride, fumaric acid, succinic acid, alkenyl Aliphatic carboxylic acids such as succinic anhydride and adipic acid; alicyclic carboxylic acids such as cyclohexanedicarboxylic acid, and the like. These polyvalent carboxylic acids may be used alone or in combination. Among these polyvalent carboxylic acids, it is desirable to use aromatic carboxylic acids. In order to secure good fixability, it is desirable to use a trivalent or higher carboxylic acid (trimellitic acid or acid anhydride thereof) together with a dicarboxylic acid in order to form a crosslinked structure or a branched structure.

  Examples of the polyhydric alcohol in the polyester resin include aliphatic diols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentylglycol, and glycerin; cyclohexanediol, cyclohexanedimethanol, Examples thereof include alicyclic diols such as hydrogenated bisphenol A; aromatic diols such as an ethylene oxide adduct of bisphenol A and a propylene oxide adduct of bisphenol A. One or more of these polyhydric alcohols may be used. Among these polyhydric alcohols, aromatic diols and alicyclic diols are preferred, and among these, aromatic diols are more desirable. In order to secure better fixability, a trihydric or higher polyhydric alcohol (glycerin, trimethylolpropane, pentaerythritol) may be used in combination with the diol in order to form a crosslinked structure or a branched structure.

  Moreover, the weight average molecular weight (Mw) of the polyester resin is preferably 5000 or more and 50000 or less, and more preferably 7000 or more and 20000 or less. When the molecular weight (Mw) is less than 5000, the glass transition temperature of the toner is lowered, and thus the storage stability such as toner blocking may be adversely affected. If the weight average molecular weight (Mw) exceeds 50,000, the hot offset resistance is sufficiently imparted, but the fixability is deteriorated and also the bleeding of the release agent present in the toner is inhibited. May adversely affect the storage stability.

As for the glass transition temperature (Tg) of the said polyester resin, it is desirable that it is the range of 50 to 80 degreeC. If Tg is lower than 50 ° C., problems may occur in terms of toner storage stability and fixed image storage stability. On the other hand, if the temperature is higher than 80 ° C., it may not be possible to fix at a lower temperature than in the past.
The Tg of the polyester resin is more preferably 50 ° C. or higher and 65 ° C. or lower.
In addition, the glass transition temperature of the said polyester resin was calculated | required as the peak temperature of the endothermic peak obtained by the said differential scanning calorimetry (DSC).

  If necessary, a polycarboxylic acid or a polyhydric alcohol may be added at the final stage of the synthesis for the purpose of adjusting the acid value or the hydroxyl value. Examples of polycarboxylic acids include aromatic carboxylic acids such as terephthalic acid, isophthalic acid, phthalic anhydride, trimellitic anhydride, pyromellitic acid, naphthalenedicarboxylic acid; maleic anhydride, fumaric acid, succinic acid, alkenyl Aliphatic carboxylic acids such as succinic anhydride and adipic acid; alicyclic carboxylic acids such as cyclohexanedicarboxylic acid; 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4- Examples thereof include aromatic carboxylic acids having at least three carboxyl groups in one molecule such as naphthalene tricarboxylic acid.

  Examples of polyhydric alcohols include aliphatic diols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentyl glycol, glycerin; cyclohexanediol, cyclohexanedimethanol, hydrogenated bisphenol A, etc. And aromatic diols such as bisphenol A ethylene oxide adduct and bisphenol A propylene oxide adduct.

The production of the polyester resin can be carried out at a polymerization temperature of 180 ° C. or higher and 230 ° C. or lower. The reaction system is reduced in pressure as necessary and reacted while removing water and alcohol generated during condensation.
When the polymerizable monomer is not dissolved or compatible at the reaction temperature, a solvent having a high boiling point may be added as a solubilizing solvent and dissolved. In this case, the polycondensation reaction is performed while distilling off the solubilizing solvent. If there is a polymerizable monomer having poor compatibility in the copolymerization reaction, the polymerizable monomer having poor compatibility and the polymerizable monomer and the acid or alcohol to be polycondensed are condensed in advance. And then polycondensation with the main component.

  Catalysts used in the production of the polyester resin include alkali metal compounds such as sodium and lithium; alkaline earth metal compounds such as magnesium and calcium; zinc, manganese, antimony, titanium, tin, zirconium, germanium and the like Metal compounds; phosphorous acid compounds; phosphoric acid compounds; and amine compounds.

The content of the polyester resin in the toner for developing an electrostatic charge image according to the exemplary embodiment is preferably, for example, from 50% by mass to 99% by mass, and more preferably from 90% by mass to 99% by mass.
In this embodiment, a known resin material such as a styrene / acrylic resin, an epoxy resin, a polyurethane resin, a polyamide resin, a cellulose resin, a polyether resin, or a polyolefin resin may be used in combination with the polyester resin as the binder resin. Good.

(Release agent)
The electrostatic image developing toner according to the exemplary embodiment includes a release agent. Examples of the release agent include paraffin waxes such as low molecular weight polypropylene and low molecular weight polyethylene; silicone resins; rosins; rice wax; carnauba wax; ester wax; Among these, paraffin wax, ester wax, montan wax and the like are preferable, and paraffin wax, ester wax and the like are more preferable. The melting temperature of the release agent used in this embodiment is preferably 60 ° C. or higher and 120 ° C. or lower, and more preferably 70 ° C. or higher and 110 ° C. or lower. The content of the release agent in the toner is desirably 0.5% by mass or more and 15% by mass or less, and more desirably 1.0% by mass or more and 12% by mass or less. If the content of the release agent is less than 0.5% by mass, peeling failure may occur particularly in oilless fixing, and gloss unevenness may deteriorate. When the content of the release agent is more than 15% by mass, the fluidity of the toner is deteriorated and the image quality and the reliability of image formation may be deteriorated.

(Inorganic metal salt)
As the inorganic metal salt, a general inorganic metal compound or a polymer thereof may be used. The metal element constituting the inorganic metal salt has a divalent or higher charge belonging to the 2A, 3A, 4A, 5A, 6A, 7A, 8, 1B, 2B, 3B group in the periodic table (long periodic table). There are suitable so-called water-soluble metal salts. Specific examples of preferred inorganic metal salts 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, calcium sulfide. And inorganic metal salt polymers. Among these, it is preferable that the metal element contained in the inorganic metal salt is Al.
As the content of the inorganic metal salt, the Net intensity of the metal element derived from the inorganic metal salt by fluorescent X-ray (XRF) analysis is preferably 0.1 or more and 0.5 or less, and 0.2 or more and 0.4 or less. More preferably.
In addition, the measuring method and measurement conditions of content of an inorganic metal salt by fluorescent X-ray analysis are as follows. As a sample pretreatment for measurement, 0.12 g of toner was compression molded under a pressure condition of 6 t for 1 minute with a pressure molding machine. A fluorescent X-ray (XRF-1500) manufactured by Shimadzu Corporation was used, and the measurement conditions were a tube voltage of 40 KV and a tube current of 70 mA.

(Other additives)
In addition to the above-described components, the electrostatic charge image developing toner according to the exemplary embodiment further includes a colorant, an internal additive, a charge control agent, inorganic powder (inorganic particles), organic particles, and the like as necessary. Various components may be added.

The electrostatic image developing toner according to the exemplary embodiment may include a colorant. The colorant may be a dye or a pigment, but is preferably a pigment from the viewpoint of light resistance and water resistance.
For example, carbon black, aniline black, 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, quinacridone, benzy Thin Yellow, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 57: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 185, C.I. I. Pigment red 238, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 180, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 74, C.I. I. Pigment blue 15: 1, C.I. I. A known pigment such as CI Pigment Blue 15: 3 is used.

In the toner for developing an electrostatic charge image of the exemplary embodiment, the content of the colorant is preferably 1 part by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the binder resin.
It is also effective to use a colorant that has been surface-treated as necessary, or a pigment dispersant. By selecting the type of the colorant, yellow toner, magenta toner, cyan toner, black toner and the like can be obtained.

  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 particles are added for various purposes, but may be added for adjusting the viscoelasticity of the toner. By adjusting the viscoelasticity, image glossiness and penetration into paper are adjusted. As the inorganic particles, for example, known inorganic particles such as silica particles, titanium oxide particles, alumina particles, cerium oxide particles, or those obtained by hydrophobizing the surface thereof may be used alone or in combination of two or more. However, silica particles having a refractive index smaller than that of the binder resin are preferably used from the viewpoint of not impairing transparency such as color developability and OHP permeability. Further, the silica particles may be subjected to various surface treatments, and for example, those subjected to surface treatment with a silane coupling agent, a titanium coupling agent, a silicone oil or the like are preferably used.

[Toner characteristics]
The toner for developing an electrostatic charge image according to the exemplary embodiment is preferably spherical with a shape factor SF1 in the range of 115 to 140.
As for the shape of the toner, the spherical toner is advantageous in terms of developability and transferability, but may be inferior to the indeterminate shape in terms of cleaning properties. When the toner has a shape in the above range, the transfer efficiency and image density are improved, high-quality image formation is performed, and the cleaning property of the surface of the photoreceptor is enhanced.
The shape factor SF1 is more preferably in the range of 120 to 138.

Here, the shape factor SF1 is obtained by the following equation (1).
SF1 = (ML ² / A) × (π / 4) × 100 (1)
In the above formula (1), ML represents the absolute maximum length of the toner particles, and A represents the projected area of the toner particles.

  SF1 is quantified mainly by analyzing a microscope image or a scanning electron microscope (SEM) image using an image analyzer, and is calculated as follows, for example. That is, an optical microscope image of particles scattered on the surface of the slide glass is taken into a Luzex image analyzer through a video camera, and the maximum length and projected area of 100 particles are obtained, calculated by the above equation (1), and the average value is calculated. It is obtained by seeking.

  The volume average particle diameter of the toner for developing an electrostatic charge image according to the exemplary embodiment is desirably 3 μm or more and 9 μm or less, more desirably 3.5 μm or more and 8.5 μm or less, and further desirably 4 μm or more and 8 μm or less. It is. If the volume average particle diameter is 3 μm or more, the decrease in toner fluidity can be suppressed, and the chargeability of each particle can be easily maintained. In addition, the charge distribution does not spread, preventing fogging on the background and preventing toner from spilling from the developer. Further, when the volume average particle diameter of the toner is 3 μm or more, the cleaning property is improved. If the volume average particle diameter is 9 μm or less, a decrease in resolution can be suppressed, so that a sufficient image quality can be obtained and the recent demand for higher image quality is satisfied.

Incidentally, the volume average particle diameter D ₅₀ is, for example, be measured by the measuring instrument such as Coulter Multisizer II (manufactured by Beckman Coulter, Inc.).

<Toner production method>
The method for producing the toner for developing an electrostatic charge image according to the exemplary embodiment is not particularly limited, and is produced by a known dry method such as a kneading / pulverizing method or a wet method such as an emulsion aggregation method or a suspension polymerization method. . Among these methods, an emulsification aggregation method that can easily produce a toner having a core-shell structure is preferable. Hereinafter, a method for producing a toner by the emulsion aggregation method will be described in detail.

  In the emulsification aggregation method according to the present embodiment, an emulsification step of emulsifying a raw material constituting a toner to form resin particles (emulsion particles), an aggregation step of forming an aggregate of the resin particles, and a fusion that fuses the aggregates Process.

(Emulsification process)
For example, the resin particle dispersion may be produced by applying a shearing force to a solution obtained by mixing an aqueous medium and a binder resin with a disperser. At that time, particles may be formed by heating to lower the viscosity of the resin component. A dispersant may be used for stabilizing the dispersed resin particles. Furthermore, if the resin is oily and dissolves in a solvent with a relatively low solubility in water, the resin is dissolved in those solvents and dispersed in water together with a dispersant and a polymer electrolyte, and then heated or decompressed. By evaporating the solvent, a resin particle dispersion is produced.

Examples of the aqueous medium include water such as distilled water and ion-exchanged water; alcohols; and the like.
Examples of the dispersant used in the emulsification step include water-soluble polymers such as polyvinyl alcohol, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, sodium polyacrylate, and sodium polymethacrylate; sodium dodecylbenzenesulfonate, Anionic surfactants such as sodium octadecyl sulfate, sodium oleate, sodium laurate, potassium stearate, cationic surfactants such as laurylamine acetate, stearylamine acetate, lauryltrimethylammonium chloride, amphoteric such as lauryldimethylamine oxide Ionic surfactant, polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene Surfactants such as nonionic surfactants such as alkyl amines; and the like are; tricalcium phosphate, aluminum hydroxide, calcium sulfate, calcium carbonate, inorganic salts such as barium carbonate.

  Examples of the disperser used for preparing the emulsion include a homogenizer, a homomixer, a pressure kneader, an extruder, and a media disperser. As the size of the resin particles, the average particle size (volume average particle size) is preferably 1.0 μm or less, more preferably in the range of 60 nm to 300 nm, and still more preferably in the range of 150 nm to 250 nm. . If it is less than 60 nm, the resin particles become stable particles in the dispersion, and thus aggregation of the resin particles may be difficult. On the other hand, if it exceeds 1.0 μm, the cohesiveness of the resin particles is improved and it becomes easy to prepare toner particles, but the particle size distribution of the toner may be widened.

  In preparing the release agent dispersion, the release agent is dispersed in water together with an ionic surfactant, a polymer electrolyte such as a polymer acid or a polymer base, and then heated to a temperature equal to or higher than the melting temperature of the release agent. Dispersion treatment is performed using a homogenizer or a pressure discharge type disperser to which a strong shearing force is applied while heating. By undergoing such treatment, a release agent dispersion is obtained. An inorganic compound such as polyaluminum chloride may be added to the dispersion during the dispersion treatment. Examples of preferable inorganic compounds include polyaluminum chloride, aluminum sulfate, highly basic polyaluminum chloride (BAC), polyaluminum hydroxide, aluminum chloride and the like. Of these, polyaluminum chloride and aluminum sulfate are preferred. The release agent dispersion is used in the emulsion aggregation method, but the release agent dispersion may also be used when the toner is produced by suspension polymerization.

By the dispersion treatment, a release agent dispersion liquid containing release agent particles having a volume average particle diameter of 1 μm or less is obtained. A more preferable volume average particle diameter of the release agent particles is 100 nm or more and 500 nm or less.
When the volume average particle diameter is less than 100 nm, the properties of the binder resin used are affected, but generally the release agent component is hardly taken into the toner. On the other hand, if it exceeds 500 nm, the dispersion state of the release agent in the toner may be insufficient.

  For the preparation of the colorant dispersion, a known dispersion method can be used. For example, a general dispersion means such as a rotary shear type homogenizer, a ball mill having a medium, a sand mill, a dyno mill, or an optimizer can be employed. Is not to be done. The colorant is dispersed in water together with a polymer electrolyte such as an ionic surfactant, a polymer acid, or a polymer base. The volume average particle diameter of the dispersed colorant particles may be 1 μm or less, but the range of 80 nm to 500 nm is preferable because the colorant is well dispersed in the toner without impairing the cohesiveness.

(Aggregation process)
In the agglomeration step, a dispersion of resin particles, a colorant dispersion, a release agent dispersion, etc. are mixed to form a mixed solution, which is heated to agglomerate at a temperature lower than the glass transition temperature of the resin particles. Form. Aggregated particles are often formed by making the pH of the mixed solution acidic under stirring. The pH is preferably in the range of 2 to 7, and in this case, it is also effective to use a flocculant.
In the aggregation step, the release agent dispersion may be added and mixed at once with various dispersions such as a resin particle dispersion, or may be added in multiple portions.

  As the aggregating agent, a surfactant having a polarity opposite to that of the surfactant used for the dispersant, an inorganic metal salt, and a divalent or higher-valent metal complex are preferably used. In particular, the use of a metal complex is particularly desirable because the amount of the surfactant used can be reduced and the charging characteristics are improved.

The inorganic metal salt described above is used as the inorganic metal salt. Of these, aluminum salts and polymers thereof are particularly preferred. In order to obtain a narrower particle size distribution, the valence of the inorganic metal salt is bivalent than monovalent, trivalent than bivalent, trivalent than trivalent, and tetravalent than trivalent. Inorganic metal salt polymers are more suitable.
In the present embodiment, it is preferable to use a polymer of a tetravalent inorganic metal salt containing aluminum in order to obtain a narrow particle size distribution.

  Further, a toner having a structure in which the surface of the core aggregated particles is coated with a resin may be prepared by additionally adding a resin particle dispersion when the aggregated particles have a desired particle size (coating step). In this case, the release agent and the colorant are not easily exposed on the toner surface, which is desirable from the viewpoint of chargeability and developability. In the case of additional addition, a flocculant may be added or pH adjustment may be performed before additional addition.

(Fusion process)
In the fusion step, the agglomeration is stopped by raising the pH of the suspension of aggregated particles to a range of 3 to 9 under stirring conditions in accordance with the aggregation step, and the glass transition temperature of the resin is higher than the glass transition temperature. The aggregated particles are fused by heating at a temperature. Moreover, when it coat | covers with the said resin, this resin is also united and a core aggregated particle is coat | covered. The heating time may be performed to the extent that fusion is performed, and may be performed for about 0.5 hour to 10 hours.

Cool after fusion to obtain fused particles. Further, in the cooling step, crystallization may be promoted by reducing the cooling rate in the vicinity of the glass transition temperature (range of glass transition temperature ± 10 ° C.) of the resin, so-called slow cooling.
The fused particles obtained by fusing are made into toner particles through a solid-liquid separation process such as filtration and, if necessary, a washing process and a drying process.

(External additive)
To the obtained toner particles, an inorganic oxide typified by silica, titania, or aluminum oxide may be added and adhered for the purpose of charge adjustment, fluidity provision, charge exchangeability, and the like. These can be performed by, for example, a V-type blender, a Henschel mixer, a Redige mixer, or the like, and may be attached in stages.

  Examples of the inorganic particles include silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, silica sand, clay, mica, wollastonite, diatomaceous earth, cerium chloride. , Bengala, chromium oxide, cerium oxide, antimony trioxide, magnesium oxide, zirconium oxide, silicon carbide, silicon nitride and the like. Among these, silica particles and / or titania particles are preferable, and hydrophobized silica particles and titania particles are particularly preferable.

The inorganic particles are generally used for the purpose of improving toner fluidity. Among the inorganic particles, by using TiO (OH) ₂ metatitanate, it has excellent transparency, good chargeability, environmental stability, fluidity, caking resistance, stable negative chargeability, and stable image quality maintainability. Is obtained. In addition, the hydrophobized compound of metatitanic acid has an electric resistance of 10 ¹⁰ Ω · cm or more, so that even if the transfer electric field is increased, high transferability can be obtained without generating a reversely charged toner. preferable. The volume average particle diameter of the external additive for the purpose of imparting fluidity is preferably in the range of 1 nm to 40 nm in terms of the primary particle diameter, and more preferably in the range of 5 nm to 20 nm. The volume average particle diameter of the external additive for the purpose of improving transferability is preferably from 50 nm to 500 nm. These external additive particles are preferably subjected to surface modification such as hydrophobization in order to stabilize the chargeability and developability.

  A conventionally known method is used as the means for surface modification. Specific examples include coupling treatments such as silane, titanate, and aluminate. The coupling agent used for the coupling treatment is not particularly limited. For example, methyltrimethoxysilane, phenyltrimethoxysilane, methylphenyldimethoxysilane, diphenyldimethoxysilane, vinyltrimethoxysilane, γ-aminopropyltrimethoxysilane , Γ-chloropropyltrimethoxysilane, γ-bromopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-ureidopropyltrimethoxysilane, fluoroalkyltrimethoxysilane, hexa Silane coupling agents such as methyldisilazane; titanate coupling agents; aluminate coupling agents;

  Furthermore, various additives may be added as necessary. Examples of these additives include other fluidizing agents, cleaning aids such as polystyrene particles, polymethyl methacrylate particles, and polyvinylidene fluoride particles, and zinc stearyl. Examples thereof include abrasives for the purpose of removing adhering substances such as amide and strontium titanate.

The amount of the external additive added is preferably in the range of 0.1 to 5 parts by mass, more preferably in the range of 0.3 to 2 parts by mass with respect to 100 parts by mass of the toner particles. When the addition amount is less than 0.1 parts by mass, the fluidity of the toner may be deteriorated, and there may be problems such as deterioration of chargeability and charge exchange property, which may be unfavorable. On the other hand, when the added amount is more than 5 parts by mass, an excessive covering state is caused, and the excessive inorganic oxide may be transferred to the contact member to cause a secondary failure.
Further, if necessary, coarse particles of toner may be removed after external addition using an ultrasonic sieving machine, a vibration sieving machine, a wind sieving machine, or the like.

  In addition to the external additives described above, other components (particles) such as a charge control agent, organic particles, a lubricant, and an abrasive may be added.

  Although there is no restriction | limiting in particular as a charge control agent, A colorless or light-colored thing is used preferably. For example, quaternary ammonium salt compounds, nigrosine compounds, complexes of aluminum, iron, chromium, and triphenylmethane pigments can be used.

Examples of the organic particles include particles usually used as an external additive on the toner surface, such as vinyl resins, polyester resins, and silicone resins. These inorganic particles and organic particles are used as fluidity aids, cleaning aids, and the like.
Examples of the lubricant include fatty acid amides such as ethylene bis stearic acid amide and oleic acid amide, and fatty acid metal salts such as zinc stearate and calcium stearate.
As an abrasive | polishing agent, the above-mentioned silica, alumina, cerium oxide etc. are mentioned, for example.

<Developer for developing electrostatic image>
The toner for developing an electrostatic charge image according to the exemplary embodiment is used as it is as a one-component developer or as a two-component developer. When used as a two-component developer, it is used by mixing with a carrier.

  The carrier that can be used in the two-component developer is not particularly limited, and a known carrier is used. Examples thereof include magnetic metals such as iron oxide, nickel and cobalt, magnetic oxides such as ferrite and magnetite, resin-coated carriers having a resin coating layer on the surface of the core material, and magnetic dispersion carriers. Further, a resin-dispersed carrier in which a conductive material or the like is dispersed in a matrix resin may be used.

  Coating resins and matrix resins used for carriers include polyethylene, polypropylene, polystyrene, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl chloride, polyvinyl ether, polyvinyl ketone, vinyl chloride-vinyl acetate copolymer, styrene-acrylic. Examples include, but are not limited to, acid copolymers, straight silicone resins composed of organosiloxane bonds or modified products thereof, fluororesins, polyesters, polycarbonates, phenol resins, epoxy resins, and the like.

  Examples of the conductive material include metals such as gold, silver and copper, carbon black, titanium oxide, zinc oxide, barium sulfate, aluminum borate, potassium titanate, tin oxide, and carbon black, but are not limited thereto. It is not something.

  Examples of the core material of the carrier include magnetic metals such as iron, nickel, and cobalt, magnetic oxides such as ferrite and magnetite, and glass beads. However, in order to use the carrier for the magnetic brush method, it is a magnetic material. It is preferable. The volume average particle diameter of the carrier core material is generally in the range of 10 μm to 500 μm, and preferably in the range of 30 μm to 100 μm.

  In order to coat the surface of the core material of the carrier with a resin, there may be mentioned a method of coating with a coating layer forming solution prepared by dissolving the coating resin and, if necessary, various additives in an appropriate solvent. The solvent is not particularly limited, and may be selected in consideration of the coating resin to be used, coating suitability, and the like.

  Specific resin coating methods include an immersion method in which the carrier core material is immersed in the coating layer forming solution, a spray method in which the coating layer forming solution is sprayed onto the surface of the carrier core material, and the carrier core material is fluidized air. A fluidized bed method in which the coating layer forming solution is sprayed in a state of being suspended by the above, a kneader coater method in which the carrier core material and the coating layer forming solution are mixed in a kneader coater, and the solvent is removed.

  The mixing ratio (mass ratio) of the electrostatic charge image developing toner according to the exemplary embodiment and the carrier in the two-component developer is in the range of toner: carrier = 1: 100 to 30: 100. : More preferably, the range is about 100 or more and 20: 100 or less.

<Image forming apparatus>
Next, an image forming apparatus according to this embodiment using the electrostatic image developing toner according to this embodiment will be described.
The image forming apparatus according to the present embodiment includes a photosensitive member, a charging unit that charges the photosensitive member, an electrostatic charge image forming unit that forms an electrostatic charge image on the surface of the charged photosensitive member, and a photosensitive member on the photosensitive member. A developing unit that develops the formed electrostatic image as a toner image with the electrostatic image developer according to the present embodiment, a transfer unit that transfers the toner image onto a transfer target, and a fixing that fixes the toner image. Means.

In this image forming apparatus, for example, the part including the developing unit may have a cartridge structure (process cartridge) that can be attached to and detached from the image forming apparatus main body. As the process cartridge, a developer holding body is used. A process cartridge according to this embodiment that is provided at least and contains the electrostatic charge image developer according to this embodiment is preferably used.
Hereinafter, an example of the image forming apparatus according to the present embodiment will be described, but the present invention is not limited thereto. The main parts shown in the figure will be described, and the description of the other parts will be omitted.

  FIG. 1 is a schematic configuration diagram showing a four-tandem color image forming apparatus. The image forming apparatus shown in FIG. 1 is a first to first electrophotographic method that outputs yellow (Y), magenta (M), cyan (C), and black (K) images based on color-separated image data. Fourth image forming units 10Y, 10M, 10C, and 10K (image forming means) are provided. These image forming units (hereinafter sometimes simply referred to as “units”) 10Y, 10M, 10C, and 10K are arranged in parallel at a predetermined distance from each other in the horizontal direction. The units 10Y, 10M, 10C, and 10K may be process cartridges that are detachable from the main body of the image forming apparatus.

Above each of the units 10Y, 10M, 10C, and 10K, an intermediate transfer belt 20 as an intermediate transfer member is extended through each unit. The intermediate transfer belt 20 is provided by being wound around a driving roller 22 and a support roller 24 that are in contact with the inner surface of the intermediate transfer belt 20 that are spaced apart from each other from the left to the right in the drawing. The vehicle travels in the direction toward the unit 10K. A force is applied to the support roller 24 in a direction away from the drive roller 22 by a spring or the like (not shown), and tension is applied to the intermediate transfer belt 20 wound around the both. Further, an intermediate transfer member cleaning device 30 is provided on the side of the image carrier of the intermediate transfer belt 20 so as to face the driving roller 22.
Further, each of the developing devices (developing means) 4Y, 4M, 4C, and 4K of the units 10Y, 10M, 10C, and 10K has yellow, magenta, cyan, and black contained in the toner cartridges 8Y, 8M, 8C, and 8K. The four colors of toner are supplied.

  Since the first to fourth units 10Y, 10M, 10C, and 10K described above have the same configuration, here, the first image that forms the yellow image disposed on the upstream side in the intermediate transfer belt traveling direction is formed. The unit 10Y will be described as a representative. Note that the second to fourth components are denoted by reference numerals with magenta (M), cyan (C), and black (K) instead of yellow (Y) in the same parts as the first unit 10Y. Description of the units 10M, 10C, and 10K will be omitted.

The first unit 10Y includes a photoreceptor 1Y that functions as an image holding member. Around the photosensitive member 1Y, a charging roller 2Y for charging the surface of the photosensitive member 1Y to a predetermined potential, and the charged surface is exposed by a laser beam 3Y based on the color-separated image signal to form an electrostatic charge image. An exposure device (electrostatic image forming means) 3 for forming, a developing device (developing means) 4Y for supplying the charged toner to the electrostatic image and developing the electrostatic image, and transferring the developed toner image onto the intermediate transfer belt 20 A primary transfer roller 5Y (primary transfer unit) that performs the transfer and a photoconductor cleaning device (cleaning unit) 6Y that removes toner remaining on the surface of the photoconductor 1Y after the primary transfer are sequentially arranged.
The primary transfer roller 5Y is disposed inside the intermediate transfer belt 20, and is provided at a position facing the photoreceptor 1Y. Further, a bias power source (not shown) for applying a primary transfer bias is connected to each of the primary transfer rollers 5Y, 5M, 5C, and 5K. Each bias power source varies the transfer bias applied to each primary transfer roller under the control of a control unit (not shown).

Hereinafter, an operation of forming a yellow image in the first unit 10Y will be described. First, prior to the operation, the surface of the photoreceptor 1Y is charged to a potential of about −600V to −800V by the charging roller 2Y.
The photoreceptor 1Y is formed by laminating a photosensitive layer on a conductive substrate (volume resistivity at 20 ° C .: 1 × 10 ⁻⁶ Ωcm or less). This photosensitive layer usually has a high resistance (a resistance equivalent to that of a general resin), but has a property that the specific resistance of the portion irradiated with the laser beam changes when irradiated with the laser beam 3Y. Therefore, a laser beam 3Y is output to the surface of the charged photoreceptor 1Y via the exposure device 3 in accordance with yellow image data sent from a control unit (not shown). The laser beam 3Y is applied to the photosensitive layer on the surface of the photoreceptor 1Y, whereby an electrostatic charge image of a yellow print pattern is formed on the surface of the photoreceptor 1Y.

The electrostatic charge image is an image formed on the surface of the photoreceptor 1Y by charging, and the specific resistance of the irradiated portion of the photosensitive layer is lowered by the laser beam 3Y, and the charged charge on the surface of the photoreceptor 1Y flows. On the other hand, this is a so-called negative latent image formed by the charge remaining in the portion not irradiated with the laser beam 3Y.
The electrostatic charge image formed on the photoreceptor 1Y in this way is rotated to a predetermined development position as the photoreceptor 1Y travels. At this development position, the electrostatic charge image on the photoreceptor 1Y is visualized (developed image) by the developing device 4Y.

  In the developing device 4Y, for example, an electrostatic charge image developer according to the present embodiment including at least yellow toner and a carrier is accommodated. The yellow toner is triboelectrically charged by being agitated inside the developing device 4Y, and has a charge of the same polarity (negative polarity) as the charged charge on the photoreceptor 1Y, and a developer roll (developer holder). Is held on. As the surface of the photoreceptor 1Y passes through the developing device 4Y, the yellow toner is electrostatically attached to the latent image portion on the surface of the photoreceptor 1Y, and the latent image is developed with the yellow toner. . The photoreceptor 1Y on which the yellow toner image is formed continues to run at a predetermined speed, and the toner image developed on the photoreceptor 1Y is conveyed to a predetermined primary transfer position.

When the yellow toner image on the photoreceptor 1Y is conveyed to the primary transfer, a primary transfer bias is applied to the primary transfer roller 5Y, and an electrostatic force from the photoreceptor 1Y toward the primary transfer roller 5Y acts on the toner image. Then, the toner image on the photoreceptor 1Y is transferred onto the intermediate transfer belt 20. The transfer bias applied at this time is a (+) polarity opposite to the polarity (−) of the toner, and is controlled to about +10 μA by the control unit (not shown) in the first unit 10Y, for example.
On the other hand, the toner remaining on the photoreceptor 1Y is removed and collected by the cleaning device 6Y.

Further, the primary transfer bias applied to the primary transfer rollers 5M, 5C, and 5K after the second unit 10M is also controlled according to the first unit.
Thus, the intermediate transfer belt 20 onto which the yellow toner image has been transferred by the first unit 10Y is sequentially conveyed through the second to fourth units 10M, 10C, and 10K, and the toner images of the respective colors are superimposed and transferred in a multiple manner. The

  The intermediate transfer belt 20 onto which the four color toner images have been transferred through the first to fourth units is arranged on the image transfer surface side of the intermediate transfer belt 20, the support roller 24 in contact with the inner surface of the intermediate transfer belt 20. The secondary transfer roller (secondary transfer means) 26 is connected to a secondary transfer portion. On the other hand, the recording paper (transfer object) P is fed at a predetermined timing to the gap where the secondary transfer roller 26 and the intermediate transfer belt 20 are pressed against each other via the supply mechanism, and the secondary transfer bias is supported. Applied to the roller 24. The transfer bias applied at this time is a (−) polarity that is the same polarity as the polarity (−) of the toner, and an electrostatic force from the intermediate transfer belt 20 toward the recording paper P is applied to the toner image, and the transfer bias is applied to the intermediate transfer belt 20. The toner image is transferred onto the recording paper P. Note that the secondary transfer bias at this time is determined according to the resistance detected by a resistance detecting means (not shown) for detecting the resistance of the secondary transfer portion, and is voltage-controlled.

  Thereafter, the recording paper P is fed to the pressure contact portion (nip portion) of the pair of fixing rolls in the fixing device (roll-type fixing means) 28, the toner image is heated, and the color-superposed toner image is melted to record the recording paper. Fixed onto P.

  Examples of the transfer target to which the toner image is transferred include plain paper and OHP sheet used for electrophotographic copying machines, printers, and the like.

The recording paper P on which the color image has been fixed is carried out toward the discharge unit, and a series of color image forming operations is completed.
The image forming apparatus exemplified above is configured to transfer the toner image onto the recording paper P via the intermediate transfer belt 20, but the present invention is not limited to this configuration, and the toner image is directly transferred from the photoconductor. It may be a structure that is transferred to a recording sheet.

<Process cartridge, toner cartridge>
FIG. 2 is a schematic configuration diagram showing an embodiment of a preferred example of a process cartridge containing an electrostatic charge image developer according to this embodiment. In the process cartridge 200, a charging roller 108, a developing device 111, a photoconductor cleaning device 113, an opening 118 for exposure, and an opening 117 for static elimination exposure are combined using a mounting rail 116 together with the photoconductor 107. , And integrated. In FIG. 2, reference numeral 300 denotes a transfer target.
The process cartridge 200 is detachable from an image forming apparatus main body including a transfer device 112, a fixing device 115, and other components (not shown). It forms a forming apparatus.

  The process cartridge 200 shown in FIG. 2 includes a charging device 108, a developing device 111, a cleaning device 113, an opening 118 for exposure, and an opening 117 for static elimination exposure. May be combined. In the process cartridge according to the present embodiment, in addition to the photosensitive member 107, the charging device 108, the developing device 111, the cleaning device (cleaning means) 113, the opening 118 for exposure, and the opening 117 for static elimination exposure. At least one selected from the group consisting of:

  Next, the toner cartridge according to this embodiment will be described. The toner cartridge according to the exemplary embodiment is detachably mounted on the image forming apparatus, and at least the toner cartridge that stores toner to be supplied to the developing unit provided in the image forming apparatus. The toner for developing an electrostatic image according to this embodiment is characterized in that Note that the toner cartridge according to the present embodiment only needs to contain at least toner, and may contain developer, for example, depending on the mechanism of the image forming apparatus.

  Therefore, in the image forming apparatus having a configuration in which the toner cartridge can be attached and detached, by using the toner cartridge containing the electrostatic image developing toner according to the present embodiment, the electrostatic image developing device according to the present embodiment is used. The toner is easily supplied to the developing device.

  The image forming apparatus shown in FIG. 1 is an image forming apparatus having a configuration in which the toner cartridges 8Y, 8M, 8C, and 8K can be attached and detached, and the developing devices 4Y, 4M, 4C, and 4K are respectively the developing devices ( And a toner supply pipe (not shown). Further, when the toner stored in the toner cartridge becomes low, the toner cartridge is replaced.

  Hereinafter, although an Example and a comparative example are given and this embodiment is described in detail in detail, this embodiment is not limited to the following examples. Unless otherwise specified, “part” and “%” are based on mass.

<Manufacture of polyester resin>
-Production of polyester resin A-
-Ethylene glycol 22.1 parts-Neopentyl glycol 21.6 parts-1,9-nonanediol 68.6 parts-Terephthalic acid 97.2 parts-Trimellitic acid 76.8 parts The temperature was raised to 200 ° C., and after confirming that the reaction system was uniformly stirred, 1.2 parts of dibutyltin oxide was added. Further, the polyester resin A having a weight average molecular weight of 75,000 is obtained by raising the temperature from the same temperature to 240 ° C. over 6 hours while distilling off the water to be generated, and continuing the dehydration condensation reaction at 240 ° C. for another 6 hours. Got.

-Production of polyester resin B-
A polyester resin B having a weight average molecular weight of 21,000 was obtained in the same manner as in the production of the polyester resin A except that the dehydration condensation time was 2 hours.

<Preparation of polyester resin latex>
-Preparation of polyester resin latex A-
The polyester resin A was transferred in a molten state to Cavitron CD1010 (manufactured by Eurotech Co., Ltd.) at a rate of 100 g / min. A 0.37% diluted aqueous ammonia solution obtained by diluting reagent ammonia water with ion-exchanged water is put into a separately prepared aqueous medium tank, and the polyester is heated at 120 ° C. with a heat exchanger at a rate of 0.1 liter per minute. Simultaneously with the resin melt, it was transferred to the Cavitron. The Cavitron was operated under conditions of a rotor rotation speed of 60 Hz and a pressure of 5 kg / cm ² to obtain a polyester resin latex A having a volume average particle size of 150 nm, a solid content of 33%, and a weight average molecular weight of 75,000.
-Preparation of polyester resin latex B-
A polyester resin latex having a particle size of 134 nm, a solid content of 31%, and a weight average molecular weight of 20,000 is the same as that for the polyester resin latex A except that the polyester resin B is used instead of the polyester resin A. B was obtained.

<Preparation of release agent dispersion>
・ Releasing agent (Nippon Seiki Co., Ltd., FT105): 90 parts ・ Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen SC): 15 parts ・ Ion-exchanged water: 270 parts The above ingredients are mixed and homogenizer (Distributed by IKA, Ultra Turrax T50) for 20 minutes, and then applied to a circulating ultrasonic disperser (manufactured by Nippon Seiki Seisakusho, RUS-600TCVP) with a number average particle size of 182 nm and a solid content of 25.2%. A mold dispersion was prepared.

<Preparation of colorant dispersion>
Carbon black (CABOT, R330): 80 parts Anionic surfactant (Daiichi Kogyo Seiyaku, Neogen SC): 10 parts Ion-exchanged water: 245 parts The above ingredients were mixed and homogenizer (IKA) (Manufactured by Ultra Turrax T50) for 20 minutes, and then applied to a circulating ultrasonic disperser (manufactured by Nippon Seiki Seisakusho, RUS-600TCVP), a colorant dispersion having a number average particle size of 154 nm and a solid content of 24.7% Was prepared.

[Example 1]
The following components were mixed and dispersed in a round stainless steel flask using a homogenizer (manufactured by IKA, Ultra Turrax T50) at 25 ° C. for 10 minutes to obtain a dispersion.
Polyester resin latex A: 509 parts Polyester resin latex B: 134.5 parts Ion exchange water: 988 parts Colorant dispersion: 80.6 parts Surfactant (Daiichi Kogyo Seiyaku, Neogen SC) : 20.4 partsReleasing agent dispersion: 73.8 parts

Thereafter, 25 parts of a 10% polyaluminum chloride aqueous solution was added to the above dispersion, and the contents in the flask were stirred and heated to 44 ° C. while being held at 44 ° C. for 35 minutes. Thereafter, 95 parts of additional polyester resin latex A and 110 parts of polyester resin latex B were added and stirred for 40 minutes. When the obtained contents were observed with an optical microscope, it was confirmed that aggregated particles having a particle size of 6.7 μm were formed.
The pH was adjusted to 7.5 with an aqueous sodium hydroxide solution. Thereafter, when the temperature was raised to 90 ° C., 25 parts of 20% HIDS (compound represented by structural formula 1) aqueous solution made by Nippon Shokubai was added, the aggregates were united over 5 hours, cooled and filtered. Then, the toner particles (A1) were obtained by thoroughly washing with ion-exchanged water and drying.

  To 100 parts of the obtained toner particles (A1), 1.5 parts of hydrophobic silica (manufactured by Nippon Aerosil Co., Ltd., RY50) was mixed and blended at 10,000 rpm for 30 seconds using a sample mill. Thereafter, the toner (A1) was prepared by sieving with a vibrating sieve having an opening of 45 μm. The toner (A1) obtained had a volume average particle diameter of 6.6 μm. GSDv, which is an index of volume particle size distribution, was 1.20.

Note that GSDv, which is an index of volume particle size distribution, is obtained by the equation “GSDv = (D84v / D16v) ^1/2 ”. Here, D84v is a particle diameter value that is 84% cumulative from the small diameter side in the volume distribution of the particle diameter, and D16v is a particle diameter value that is cumulative 16% from the small diameter side in the volume distribution of the particle diameter.
D16v and D84v were measured with a Coulter Multisizer II (manufactured by Coulter).

  The tan δ of the toner (A1) was measured by the above method and found to be 0.56. Further, when 0.1 g of toner (1) is dispersed in 50 mL of 0.5 mol / L NaOH aqueous solution at 28 ° C. to obtain a dispersion, the content of the compound represented by Structural Formula 1 contained in the dispersion Was 680 ppm when measured by the method described above.

<Preparation of carrier 1>
・ Toluene 14 parts ・ Styrene-methyl methacrylate copolymer (component ratio: 80/20, weight average molecular weight: 70,000) 2 parts ・ MZ500 (zinc oxide, titanium industry) 0.6 parts The solution for forming a coating layer in which zinc oxide was dispersed by stirring was prepared. Next, this coating solution and 100 parts of ferrite particles (volume average particle size: 38 μm) are put in a vacuum degassing kneader and stirred at 60 ° C. for 30 minutes, and then degassed by further reducing pressure while heating. The carrier 1 was produced by drying.

<Preparation of electrostatic charge image developer>
The obtained carrier 1 and toner (A1) were mixed at a ratio of 100 parts: 8 parts by a 2 liter V blender to prepare an electrostatic charge image developer (A1).

<Evaluation>
The electrostatic charge image developer (A1) is loaded into a color copying machine DocuCentreColor 400 (manufactured by Fuji Xerox Co., Ltd.) from which the fixing device has been taken out, and adjusted so that the applied toner amount is 0.45 mg / cm ² to obtain an unfixed image. Output. The output image was a halftone solid image with a 50 mm × 50 mm large image density of 50%, and the paper used was “FR” (Beck smoothness: 25 sec, manufactured by Fuji Xerox Interfield).
To fix the image, the fixing device taken out from the monochrome copying machine DocuCenterf1100 (manufactured by Fuji Xerox Co., Ltd.) was modified so that the roll temperature of the fixing device could be changed. The unfixed image was fixed by changing the temperature of the fixing device from 140 ° C. to 210 ° C. by 5 ° C. to obtain a fixed image.

<Evaluation of storability and durability of halftone images>
A fixed image portion obtained at the minimum fixing temperature (minimum temperature at which low temperature offset does not occur) was bent using a weight with a constant load, and graded according to the degree of image defect of the portion. The evaluation criteria are as follows.
-Evaluation criteria-
G1: The image defect is only the crease part, and has high storage stability and durability. G2: The image defect extends to the crease part and its periphery, but is slight and within an allowable range. G3: The image defect is a crease. As a result of the measurement exceeding the permissible range over the part and the surrounding area, the storage stability and durability were G1.

<Evaluation of image blur>
The obtained fixed image was visually observed and graded. The evaluation criteria are as follows.
-Evaluation criteria-
G1: No image blur was observed G2: Image blur was slightly observed under the use of a loupe, but no image blur was visually observed, and within an allowable range G3: Image blur was observed visually, As a result of the measurement exceeding the allowable range, the image blur was G2.

[Example 2]
The following components were mixed and dispersed in a round stainless steel flask using a homogenizer (manufactured by IKA, Ultra Turrax T50) at 25 ° C. for 10 minutes to obtain a dispersion.
Polyester resin latex A: 130.2 parts Polyester resin latex B: 550.6 parts Ion exchange water: 971 parts Colorant dispersion: 60.5 parts Surfactant (Daiichi Kogyo Seiyaku, Neogen) SC): 20.4 partsReleasing agent dispersion: 73.8 parts

Thereafter, 27.5 parts of a 10% polyaluminum chloride aqueous solution was added to the above dispersion, and the contents in the flask were stirred and heated to 44 ° C. while being held at 44 ° C. for 35 minutes. Thereafter, 95 parts of additional polyester resin latex A and 110 parts of polyester resin latex B were added and stirred for 40 minutes. When the obtained contents were observed with an optical microscope, it was confirmed that aggregated particles having a particle size of 6.7 μm were formed.
The pH was adjusted to 7.5 with an aqueous sodium hydroxide solution. Thereafter, when the temperature was raised to 90 ° C., 25 parts of 20% HIDS (compound represented by structural formula 1) aqueous solution made by Nippon Shokubai was added, the aggregates were united over 5 hours, cooled and filtered. The toner particles (A2) were obtained by thoroughly washing with ion exchange water and drying.

  To 100 parts of the obtained toner particles (A2), silica was mixed and blended in the same manner as in the toner (A1) to prepare a toner (A2). The toner (A2) obtained had a volume average particle diameter of 6.6 μm. GSDv, which is an index of volume particle size distribution, was 1.20.

  The toner (A2) had a tan δ of 1.92. Further, the content of the compound represented by Structural Formula 1 contained in the dispersion when 0.1 g of toner (A2) was dispersed in 50 mL of 0.5 mol / L NaOH aqueous solution at 28 ° C. Was measured by the method described above, and it was 540 ppm.

<Preparation of electrostatic charge image developer>
Carrier 1 and toner (A2) were mixed at a ratio of 100 parts: 8 parts by a 2 liter V blender to produce an electrostatic charge image developer (A2).

<Evaluation>
As with the electrostatic charge image developer (A1), the electrostatic charge image developer (A2) was evaluated for halftone image storability, durability, and blur. The storability and durability were G2, and the blur was G2. .

[Example 3]
The following components were mixed and dispersed in a round stainless steel flask using a homogenizer (manufactured by IKA, Ultra Turrax T50) at 25 ° C. for 10 minutes to obtain a dispersion.
Polyester resin latex A: 395.2 parts Polyester resin latex B: 278.5 parts Ion exchange water: 988 parts Colorant dispersion: 60.5 parts Surfactant (Daiichi Kogyo Seiyaku, Neogen) SC): 20.4 partsReleasing agent dispersion: 63.3 parts

Thereafter, 12.5 parts of a 10% aqueous solution of polyaluminum chloride was added to the above dispersion, and the contents in the flask were stirred and heated to 44 ° C., and held at 44 ° C. for 35 minutes. Thereafter, 95 parts of additional polyester resin latex A and 110 parts of polyester resin latex B were added and stirred for 40 minutes. When the obtained contents were observed with an optical microscope, it was confirmed that aggregated particles having a particle size of 6.7 μm were formed.
The pH was adjusted to 7.5 with an aqueous sodium hydroxide solution. Thereafter, when the temperature was raised to 90 ° C., 25 parts of 20% HIDS (compound represented by structural formula 1) aqueous solution made by Nippon Shokubai was added, the aggregates were united over 5 hours, cooled and filtered. Then, the toner particles (A3) were obtained by thoroughly washing with ion-exchanged water and drying.

  In 100 parts of the obtained toner particles (A3), silica was mixed and blended in the same manner as in the toner (A1) to prepare a toner (A3). The toner (A3) obtained had a volume average particle diameter of 6.6 μm. GSDv, which is an index of volume particle size distribution, was 1.20.

  The tan δ of the toner (A3) was 1.02. The content of the compound represented by the structural formula 1 contained in the dispersion when 0.1 g of toner (A3) was dispersed in 50 mL of 0.5 mol / L NaOH aqueous solution at 28 ° C. Was 6 ppm when measured by the method described above.

<Preparation of electrostatic charge image developer>
Carrier 1 and toner (A3) were mixed at a ratio of 100 parts: 8 parts by a 2 liter V blender to prepare an electrostatic charge image developer (A3).
<Evaluation>
As with the electrostatic charge image developer (A1), the electrostatic charge image developer (A3) was evaluated for storability, durability and bleeding of the halftone image. The storage stability and durability were G2, and the bleeding was G1. .

[Example 4]
The following components were mixed and dispersed in a round stainless steel flask using a homogenizer (manufactured by IKA, Ultra Turrax T50) at 25 ° C. for 10 minutes to obtain a dispersion.
Polyester resin latex A: 130.2 parts Polyester resin latex B: 550.6 parts Ion exchange water: 971 parts Colorant dispersion: 60.5 parts Surfactant (Daiichi Kogyo Seiyaku, Neogen) SC): 20.4 partsReleasing agent dispersion: 73.8 parts

Thereafter, 27.5 parts of a 10% polyaluminum chloride aqueous solution was added to the above dispersion, and the contents in the flask were stirred and heated to 44 ° C. while being held at 44 ° C. for 35 minutes. Thereafter, 95 parts of additional polyester resin latex A and 110 parts of polyester resin latex B were added and stirred for 40 minutes. When the obtained contents were observed with an optical microscope, it was confirmed that aggregated particles having a particle size of 6.7 μm were formed.
The pH was adjusted to 7.5 with an aqueous sodium hydroxide solution. Thereafter, when the temperature was raised to 90 ° C., 25 parts of 20% HIDS (compound represented by structural formula 1) aqueous solution made by Nippon Shokubai was added, the aggregates were united over 5 hours, cooled and filtered. Then, the toner particles (A4) were obtained by thoroughly washing with ion exchange water and drying.

  To 100 parts of the obtained toner particles (A4), silica was mixed and blended in the same manner as in the toner (A1) to prepare a toner (A4). The toner (A4) obtained had a volume average particle diameter of 6.6 μm. GSDv, which is an index of volume particle size distribution, was 1.20.

  The tan δ of the toner (A4) was 0.74. Further, the content of the compound represented by Structural Formula 1 contained in the dispersion when 0.1 g of toner (A4) is dispersed in 50 mL of 0.5 mol / L NaOH aqueous solution at 28 ° C. Was measured by the method described above, and it was 172 ppm.

<Preparation of electrostatic charge image developer>
Carrier 1 and toner (A4) were mixed at a ratio of 100 parts: 8 parts by a 2 liter V blender to prepare an electrostatic charge image developer (A4).
<Evaluation>
As with the electrostatic charge image developer (A1), the electrostatic charge image developer (A4) was evaluated for storability, durability and bleeding of the halftone image. The storage stability and durability were G2, and the bleeding was G1. .

[Example 5]
The following components were mixed and dispersed in a round stainless steel flask using a homogenizer (manufactured by IKA, Ultra Turrax T50) at 25 ° C. for 10 minutes to obtain a dispersion.
Polyester resin latex A: 245.5 parts Polyester resin latex B: 389.2 parts Ion exchange water: 965 parts Colorant dispersion: 90.7 parts Surfactant (Daiichi Kogyo Seiyaku, Neogen) SC): 20.4 partsReleasing agent dispersion: 94.9 parts

Thereafter, 62.5 parts of a 10% polyaluminum chloride aqueous solution was added to the above dispersion, and the contents in the flask were stirred and heated to 44 ° C. while being held at 44 ° C. for 35 minutes. Thereafter, 95 parts of additional polyester resin latex A and 110 parts of polyester resin latex B were added and stirred for 40 minutes. When the obtained contents were observed with an optical microscope, it was confirmed that aggregated particles having a particle size of 6.7 μm were formed.
The pH was adjusted to 7.5 with an aqueous sodium hydroxide solution. Thereafter, when the temperature was raised to 90 ° C., 25 parts of 20% HIDS (compound represented by structural formula 1) aqueous solution made by Nippon Shokubai was added, the aggregates were united over 5 hours, cooled and filtered. Then, the toner particles (A5) were obtained by thoroughly washing with ion exchange water and drying.

  In 100 parts of the obtained toner particles (A5), silica was mixed and blended in the same manner as in the toner (A1) to prepare a toner (A5). The toner (A5) obtained had a volume average particle diameter of 6.6 μm. GSDv, which is an index of volume particle size distribution, was 1.20.

  The tan δ of the toner (A5) was 1.25. Further, the content of the compound represented by Structural Formula 1 contained in the dispersion when 0.1 g of toner (A5) is dispersed in 50 mL of 0.5 mol / L NaOH aqueous solution at 28 ° C. Was measured by the method described above, and it was 983 ppm.

<Preparation of electrostatic charge image developer>
Carrier 1 and toner (A5) were mixed at a ratio of 100 parts: 8 parts with a 2 liter V blender to prepare an electrostatic charge image developer (A5).
<Evaluation>
As with the electrostatic charge image developer (A1), the electrostatic charge image developer (A5) was evaluated for storability, durability and bleeding of the halftone image. The storage stability and durability were G1, and the bleeding was G2. .

[Example 6]
The following components were mixed and dispersed in a round stainless steel flask using a homogenizer (manufactured by IKA, Ultra Turrax T50) at 25 ° C. for 10 minutes to obtain a dispersion.
Polyester resin latex A: 386.2 parts Polyester resin latex B: 272.2 parts Ion exchange water: 982 parts Colorant dispersion: 60.5 parts Surfactant (Daiichi Kogyo Seiyaku, Neogen) SC): 20.4 partsReleasing agent dispersion: 84.4 parts

Thereafter, 37.5 parts of a 10% iron (III) chloride aqueous solution was added to the above dispersion, and the contents in the flask were heated and stirred to 44 ° C. while stirring, and held at 44 ° C. for 35 minutes. Thereafter, 95 parts of additional polyester resin latex A and 110 parts of polyester resin latex B were added and stirred for 40 minutes. When the obtained contents were observed with an optical microscope, it was confirmed that aggregated particles having a particle size of 6.7 μm were formed.
The pH was adjusted to 7.5 with an aqueous sodium hydroxide solution. Thereafter, when the temperature was raised to 90 ° C., 25 parts of 20% HIDS (compound represented by structural formula 1) aqueous solution made by Nippon Shokubai was added, the aggregates were united over 5 hours, cooled and filtered. The toner particles (A6) were obtained by thoroughly washing with ion exchange water and drying.

  In 100 parts of the obtained toner particles (A6), silica was mixed and blended in the same manner as in the toner (A1) to prepare a toner (A6). The toner (A6) obtained had a volume average particle diameter of 6.6 μm. GSDv, which is an index of volume particle size distribution, was 1.20.

  The tan δ of the toner (A6) was 1.08. In addition, the content of the compound represented by Structural Formula 1 contained in the dispersion when 0.1 g of toner (A6) is dispersed in 50 mL of 0.5 mol / L NaOH aqueous solution at 28 ° C. Was 720 ppm as measured by the method described above.

<Preparation of electrostatic charge image developer>
Carrier 1 and toner (A6) were mixed at a ratio of 100 parts: 8 parts by a 2 liter V blender to prepare an electrostatic charge image developer (A6).
<Evaluation>
As with the electrostatic charge image developer (A1), the electrostatic charge image developer (A6) was evaluated for half-tone image storability, durability and bleeding. The storage stability and durability were G2, and the bleeding was G2. .

[Comparative Example 1]
The following components were mixed and dispersed in a round stainless steel flask using a homogenizer (manufactured by IKA, Ultra Turrax T50) at 25 ° C. for 10 minutes to obtain a dispersion.
Polyester resin latex A: 345.8 parts Polyester resin latex B: 299.1 parts Ion exchange water: 976 parts Colorant dispersion: 90.7 parts Surfactant (Daiichi Kogyo Seiyaku, Neogen) SC): 20.4 partsReleasing agent dispersion: 73.8 parts

Thereafter, 31.2 parts of a 10% polyaluminum chloride aqueous solution was added to the above dispersion, and the contents in the flask were stirred and heated to 44 ° C. while being held at 44 ° C. for 35 minutes. Thereafter, 95 parts of additional polyester resin latex A and 110 parts of polyester resin latex B were added and stirred for 40 minutes. When the obtained contents were observed with an optical microscope, it was confirmed that aggregated particles having a particle size of 6.7 μm were formed.
The pH was adjusted to 9.0 with an aqueous sodium hydroxide solution. Thereafter, the temperature was raised and the temperature reached 90 ° C., and the aggregates were united over 5 hours, cooled, filtered, sufficiently washed with ion-exchanged water, and dried to obtain toner particles (B1).

  To 100 parts of the obtained toner particles (B1), silica was mixed and blended in the same manner as in the toner (A1) to prepare a toner (B1). The volume average particle size of the obtained toner (B1) was 6.6 μm. GSDv, which is an index of volume particle size distribution, was 1.20.

  The tan δ of the toner (B1) was 1.31. Further, the content of the compound represented by Structural Formula 1 contained in the dispersion when 0.1 g of toner (B1) is dispersed in 50 mL of 0.5 mol / L NaOH aqueous solution at 28 ° C. Was measured by the above-mentioned method and found to be 0 ppm.

<Preparation of electrostatic charge image developer>
Carrier 1 and toner (B1) were mixed in a ratio of 100 parts: 8 parts by a 2 liter V blender to produce an electrostatic charge image developer (B1).
<Evaluation>
As with the electrostatic charge image developer (A1), the electrostatic charge image developer (B1) was evaluated for storability, durability and bleeding of the halftone image. The storage stability and durability were G3, and the bleeding was G3. .

[Comparative Example 2]
The following components were mixed and dispersed in a round stainless steel flask using a homogenizer (manufactured by IKA, Ultra Turrax T50) at 25 ° C. for 10 minutes to obtain a dispersion.
Polyester resin latex A: 310.6 parts Polyester resin latex B: 328.3 parts Ion exchange water: 972 parts Colorant dispersion: 90.7 parts Surfactant (Daiichi Kogyo Seiyaku, Neogen) SC): 20.4 partsReleasing agent dispersion: 84.4 parts

Thereafter, 75 parts of a 10% polyaluminum chloride aqueous solution was added to the above dispersion, and the contents in the flask were stirred and heated to 44 ° C. while being held at 44 ° C. for 35 minutes. Thereafter, 95 parts of additional polyester resin latex A and 110 parts of polyester resin latex B were added and stirred for 40 minutes. When the obtained contents were observed with an optical microscope, it was confirmed that aggregated particles having a particle size of 6.7 μm were formed.
The pH was adjusted to 7.5 with an aqueous sodium hydroxide solution. Thereafter, when the temperature was raised to 90 ° C., 25 parts of 20% HIDS (compound represented by structural formula 1) aqueous solution made by Nippon Shokubai was added, the aggregates were united over 5 hours, cooled and filtered. Then, the toner particles (B2) were obtained by thoroughly washing with ion exchange water and drying.

  Silica was mixed and blended with 100 parts of the obtained toner particles (B2) in the same manner as in the toner (A1) to prepare a toner (B2). The toner (B2) obtained had a volume average particle diameter of 6.6 μm. GSDv, which is an index of volume particle size distribution, was 1.20.

  The tan δ of the toner (B2) was 1.07. Further, the content of the compound represented by Structural Formula 1 contained in the dispersion when 0.1 g of toner (B2) is dispersed in 50 mL of 0.5 mol / L NaOH aqueous solution at 28 ° C. Was measured by the above-mentioned method and found to be 1035 ppm.

<Preparation of electrostatic charge image developer>
Carrier 1 and toner (B2) were mixed at a ratio of 100 parts: 8 parts by a 2 liter V blender to prepare an electrostatic charge image developer (B2).
<Evaluation>
As with the electrostatic charge image developer (A1), the electrostatic charge image developer (B2) was evaluated for halftone image storability, durability, and bleeding. The storage stability and durability were G3, and the bleed was G3. .

[Comparative Example 3]
The following components were mixed and dispersed in a round stainless steel flask using a homogenizer (manufactured by IKA, Ultra Turrax T50) at 25 ° C. for 10 minutes to obtain a dispersion.
-Polyester resin latex A: 572.6 parts-Polyester resin latex B: 67.2 parts-Ion exchange water: 991 parts-Colorant dispersion: 70.6 parts-Surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen SC): 20.4 partsReleasing agent dispersion: 84.4 parts

Thereafter, 31.25 parts of a 10% polyaluminum chloride aqueous solution was added to the above dispersion, and the contents in the flask were heated and stirred to 44 ° C. while stirring, and held at 44 ° C. for 35 minutes. Thereafter, 95 parts of additional polyester resin latex A and 110 parts of polyester resin latex B were added and stirred for 40 minutes. When the obtained contents were observed with an optical microscope, it was confirmed that aggregated particles having a particle size of 6.7 μm were formed.
The pH was adjusted to 7.5 with an aqueous sodium hydroxide solution. Thereafter, when the temperature was raised to 90 ° C., 25 parts of 20% HIDS (compound represented by structural formula 1) aqueous solution made by Nippon Shokubai was added, the aggregates were united over 5 hours, cooled and filtered. Then, after sufficiently washing with ion-exchanged water, it was dried to obtain toner particles (B3).

  To 100 parts of the obtained toner particles (B3), silica was mixed and blended in the same manner as in the toner (A1) to prepare a toner (B3). The toner (B3) obtained had a volume average particle diameter of 6.6 μm. GSDv, which is an index of volume particle size distribution, was 1.20.

  The tan δ of the toner (B3) was 0.45. Further, the content of the compound represented by Structural Formula 1 contained in the dispersion when 0.1 g of toner (B3) was dispersed in 50 mL of 0.5 mol / L NaOH aqueous solution at 28 ° C. Was measured by the method described above, and it was 862 ppm.

<Preparation of electrostatic charge image developer>
Carrier 1 and toner (B3) were mixed at a ratio of 100 parts: 8 parts by a 2 liter V blender to produce an electrostatic charge image developer (B3).
<Evaluation>
Similar to the electrostatic charge image developer (A1), the halftone image storability, durability and blur of the electrostatic charge image developer (B3) were evaluated. The storage stability and durability were G2, and the blur was G3. .

[Comparative Example 4]
The following components were mixed and dispersed in a round stainless steel flask using a homogenizer (manufactured by IKA, Ultra Turrax T50) at 25 ° C. for 10 minutes to obtain a dispersion.
Polyester resin latex A: 130.2 parts Polyester resin latex B: 550.6 parts Ion exchange water: 971 parts Colorant dispersion: 60.5 parts Surfactant (Daiichi Kogyo Seiyaku, Neogen) SC): 20.4 partsReleasing agent dispersion: 73.8 parts

Thereafter, 37.5 parts of a 10% aqueous polyaluminum chloride solution was added to the above dispersion, and the contents in the flask were stirred and heated to 44 ° C. while being held at 44 ° C. for 35 minutes. Thereafter, 95 parts of additional polyester resin latex A and 110 parts of polyester resin latex B were added and stirred for 40 minutes. When the obtained contents were observed with an optical microscope, it was confirmed that aggregated particles having a particle size of 6.7 μm were formed.
The pH was adjusted to 7.5 with an aqueous sodium hydroxide solution. Thereafter, when the temperature was raised to 90 ° C., 25 parts of 20% HIDS (compound represented by structural formula 1) aqueous solution made by Nippon Shokubai was added, the aggregates were united over 5 hours, cooled and filtered. Then, the toner particles (B4) were obtained by thoroughly washing with ion-exchanged water and drying.

  To 100 parts of the obtained toner particles (B4), silica was mixed and blended in the same manner as in the toner (A1) to prepare a toner (B4). The toner (B4) obtained had a volume average particle diameter of 6.6 μm. GSDv, which is an index of volume particle size distribution, was 1.20.

  The tan δ of the toner (B4) was 2.13. Further, the content of the compound represented by Structural Formula 1 contained in the dispersion when 0.1 g of toner (B4) is dispersed in 50 mL of 0.5 mol / L NaOH aqueous solution at 28 ° C. Was 381 ppm as measured by the method described above.

<Preparation of electrostatic charge image developer>
Carrier 1 and toner (B4) were mixed at a ratio of 100 parts: 8 parts by a 2 liter V blender to prepare an electrostatic charge image developer (B4).
<Evaluation>
As in the case of the electrostatic charge image developer (A1), the halftone image storability, durability and blur of the electrostatic charge image developer (B4) were evaluated. As a result, the storage stability and durability were G3, and the bleed was G3. .

[Comparative Example 5]
The following components were mixed and dispersed in a round stainless steel flask using a homogenizer (manufactured by IKA, Ultra Turrax T50) at 25 ° C. for 10 minutes to obtain a dispersion.
Polyester resin latex A: 390.7 parts Polyester resin latex B: 275.3 parts Ion exchange water: 984 parts Colorant dispersion: 40.3 parts Surfactant (Daiichi Kogyo Seiyaku, Neogen) SC): 20.4 partsReleasing agent dispersion: 94.9 parts

Thereafter, 42.5 parts of a 10% polyaluminum chloride aqueous solution was added to the above dispersion, and the contents in the flask were stirred while heating to 44 ° C., and held at 44 ° C. for 35 minutes. Thereafter, 95 parts of additional polyester resin latex A and 110 parts of polyester resin latex B were added and stirred for 40 minutes. When the obtained contents were observed with an optical microscope, it was confirmed that aggregated particles having a particle size of 6.7 μm were formed.
The pH was adjusted to 7.5 with an aqueous sodium hydroxide solution. After that, when the temperature was raised to 90 ° C., 25 parts of 20% EDTA aqueous solution manufactured by Kirest Co., Ltd. was added, the aggregates were united over 5 hours, cooled, filtered, and ion-exchanged water. After thorough washing and drying, toner particles (B5) were obtained.

  To 100 parts of the obtained toner particles (B5), silica was mixed and blended in the same manner as in the toner (A1) to prepare a toner (B5). The toner (B5) obtained had a volume average particle diameter of 6.6 μm. GSDv, which is an index of volume particle size distribution, was 1.20.

  The tan δ of the toner (B5) was 0.94. Further, the content of EDTA contained in the dispersion was measured by the above method when 0.1 g of toner (B5) was dispersed in 50 mL of 0.5 mol / L NaOH aqueous solution at 28 ° C. As a result, it was 671 ppm. The EDTA content was measured in the same manner as in the case of the compound represented by Structural Formula 1. Further, the content of the compound represented by Structural Formula 1 was 0 ppm.

<Preparation of electrostatic charge image developer>
Carrier 1 and toner (B5) were mixed at a ratio of 100 parts: 8 parts by a 2 liter V blender to prepare an electrostatic charge image developer (B5).
<Evaluation>
As in the case of the electrostatic charge image developer (A1), the halftone image storability, durability and bleeding were evaluated for the electrostatic charge image developer (B5). As a result, the storage stability and durability were G3, and the bleed was G3. .

1Y, 1M, 1C, 1K, 107 photoconductor (image carrier)
2Y, 2M, 2C, 2K, 108 Charging roller 3Y, 3M, 3C, 3K Laser beam 3, 110 Exposure device 4Y, 4M, 4C, 4K, 111 Developing device (developing means)
5Y, 5M, 5C, 5K Primary transfer rollers 6Y, 6M, 6C, 6K, 113 Photoconductor cleaning device (cleaning means)
8Y, 8M, 8C, 8K Toner cartridge 10Y, 10M, 10C, 10K Unit 20 Intermediate transfer belt 22 Drive roller 24 Support roller 26 Secondary transfer roller (transfer means)
28, 115 Fixing device (fixing means)
30 Intermediate transfer member cleaning device 112 Transfer device 116 Mounting rail 117 Opening 118 for static elimination exposure Opening 200 for exposure Process cartridge,
P, 300 Recording paper (transfer object)

Claims (6)

A polyester resin, a release agent, an inorganic metal salt, and a compound represented by the following structural formula 1,
Tan δ at 140 ° C. and 1 Hz is 0.5 or more and 2.0 or less,
When 0.1 g of the present toner is dispersed in 50 mL of a 0.5 mol / L NaOH aqueous solution at 28 ° C. to obtain a dispersion, the content of the compound represented by the following structural formula 1 contained in the dispersion is 1 ppm or more. An electrostatic image developing toner having a concentration of 1000 ppm or less.

In Structural Formula 1, A represents a hydrogen atom or an alkali metal atom.   The electrostatic image developing toner according to claim 1, wherein the metal element contained in the inorganic metal salt is Al.   An electrostatic charge image developer comprising the toner for developing an electrostatic charge image according to claim 1.   A toner cartridge containing at least toner, wherein the toner is the electrostatic image developing toner according to claim 1.   A process cartridge comprising at least a developer holder and containing the electrostatic charge image developer according to claim 3.   The photosensitive member, charging means for charging the photosensitive member, electrostatic charge image forming means for forming an electrostatic charge image on the surface of the charged photosensitive member, and the electrostatic charge image formed on the photosensitive member. An image forming apparatus comprising: a developing unit that develops a toner image with the electrostatic charge image developer according to 3; a transfer unit that transfers the toner image onto a transfer target; and a fixing unit that fixes the toner image.