JP7134762B2 - Toner and image forming method - Google Patents

Description

The present invention relates to toners for developing electrostatic images used in image forming processes such as electrophotography and electrostatic printing.

In recent years, demands for copiers and printers are diversified, and among them, high image quality is particularly demanded. Improving the transferability of toner can be cited as a technique for improving image quality, and a transfer method using an intermediate transfer member such as an intermediate transfer belt is effective for achieving stable transfer. As a technique for improving the transferability of toner, Japanese Patent Application Laid-Open No. 2002-200000 discloses that the surfaces of toner particles are evenly covered with a silicon compound to reduce the adhesive force of the toner, thereby improving the transferability.

JP 2017-138462 A

When an intermediate transfer member is used to form a full-color image, multiple colors of toner are transferred onto the intermediate transfer member. A phenomenon (retransfer) in which the toner moves from the body onto the photoreceptor may occur. In Japanese Patent Application Laid-Open No. 2002-100001, the discharge in the nip between the photoreceptor and the intermediate transfer member may cause the toner to become positive, resulting in re-transfer.
SUMMARY OF THE INVENTION It is an object of the present invention to provide a toner which is excellent in transferability and resistance to re-transfer through durability, and an image forming apparatus using the toner.

The present invention is a toner having toner particles containing a binder resin and a pigment (excluding the case where the toner particles contain a resin having an ionic functional group and a pKa of 6.0 or more and 9.0 or less). ) and
the toner particles having a surface layer containing an organosilicon polymer;
the pigment contains an organic dye having a basic site,
The organic dye having a basic moiety has a structure represented by the following formula (1),
The pKb of the pigment is 3.0 or more and 7.0 or less .
This toner is characterized by:
(The pKb is obtained by mixing 1.0 parts by mass of the pigment, 14.0 parts by mass of toluene and 6.0 parts by mass of ethanol, and dispersing the mixture together with 30.0 parts by mass of 0.8 mm glass beads with a paint shaker for 3 hours. is the pKb measured by the 0.1 mol/L HCl/EtOH neutralization test of the dispersion.
Accurately weigh 0.100 g of the resin having an ionic functional group and a pKa of 6.0 or more and 9.0 or less in a 250 mL tall beaker, add 150 mL of THF, dissolve over 30 minutes, and add a pH electrode to this solution. , read the pH of the THF solution of the sample, then add 10 μL of 0.1 mol / L potassium hydroxide ethyl alcohol solution at a time, read the pH each time, perform titration, pH becomes 10 or more, add 30 μL Add 0.1 mol/L potassium hydroxide ethyl alcohol solution until there is no change in pH, and plot the pH against the amount of 0.1 mol/L potassium hydroxide ethyl alcohol solution added from the obtained results to obtain a titration curve. The neutralization point is defined as the point where the slope of the pH change is greatest from the obtained titration curve. The pKa is the same value as the pH at half the amount of the 0.1 mol/L potassium hydroxide ethyl alcohol solution required up to the neutralization point, and the pH at half the amount is read from the titration curve. )
The present invention also provides a charging step of charging an image carrier using a charging member that contacts the image carrier;
an electrostatic latent image forming step of forming an electrostatic latent image on the image carrier;
a developing step of developing the electrostatic latent image with toner to form a toner image;
a transfer step of transferring the toner image onto a recording medium via an intermediate transfer member; and
heat-fixing the toner image transferred onto the recording medium;
An image forming method comprising
The image forming method is characterized in that the toner having the above composition is used as the toner.

According to the present invention, it is possible to provide a toner that is excellent in transferability and retransfer suppression through durability.

1 is a schematic cross-sectional view showing an example of an image forming apparatus in which the toner of the present invention can be preferably used; FIG. FIG. 4 is a diagram showing an example of a jig used for measuring the amount of charge on the developing roller;

As a result of intensive studies, the present inventors have found a toner having toner particles containing a binder resin and a pigment, wherein the toner particles have a surface layer containing an organosilicon polymer, and the pigment is 3.0 or more. By having a pKb of 0.0 or less, the above problems have been solved.

The pKb is a dispersion obtained by mixing 1.0 parts by mass of a pigment, 14.0 parts by mass of toluene and 6.0 parts by mass of ethanol, and dispersing the mixture together with 30.0 parts by mass of 0.8 mm glass beads with a paint shaker for 3 hours. pKb measured by 0.1 mol/L HCl/EtOH neutralization test. A detailed measurement method will be described later.

The present inventors have investigated a toner having toner particles containing an organosilicon polymer, and have attempted to improve the transferability and the image quality by reducing the adhesion force of the toner. Furthermore, they have found that by controlling the pKb of the pigment to 3.0 or more and 7.0 or less, an unexpected effect of improving retransfer suppression can be obtained.

Although the mechanism by which the toner of the present invention improves retransfer suppression is not clear, it is speculated as follows.

Retransfer occurs when the toner transferred (primary transfer) onto the intermediate transfer member in the image forming section on the upstream side passes through the potential portion of the non-image portion of the photoreceptor in the image forming section on the downstream side. , is considered to occur because the polarity is reversed from negative to positive and transferred onto the photoreceptor.

It is considered that the surface layer containing the organosilicon polymer of the toner of the present invention is negative, and the pigment having a pKb of 3.0 to 7.0 is positive. In the case of the above combination, even when the toner is discharged, it is believed that the transfer of electric charge occurs immediately within the toner particles and between the toner particles, so that the toner surface can be prevented from becoming positive and the retransfer can be effectively suppressed.

If the pKb is less than 3.0, the positive property is too strong and the toner becomes difficult to be charged, resulting in poor transferability. On the other hand, when the pKb is more than 7.0, the positive property is weak, and the transfer of charges within and between the toner particles does not occur quickly, resulting in deterioration of retransfer inhibition. More preferably, the pKb of the pigment is 4.5 or more and 6.5 or less.

[Organosilicon polymer]
The polarity of the organosilicon polymer of the present invention can be adjusted by selecting materials such as the number of carbon atoms directly bonded to the silicon atoms of the organosilicon polymer and the length of the carbon chain. The toner particles have a surface layer containing an organosilicon polymer, and the number of carbon atoms directly bonded to the silicon atoms of the organosilicon polymer is 1 to 3 (preferably 1 to 2). , more preferably one).

In addition, the polarity can be controlled by adjusting the uneven shape of the surface layer containing the organosilicon polymer and adjusting the network structure connecting the protrusions.

These adjustments can be made by adjusting the timing and form of addition of the organosilicon polymer, and the pH, temperature, time, etc. when pretreating the organosilicon polymer.

A specific example of the process of forming the surface layer containing the organosilicon polymer will be described below, but the process is not limited to this.

First, toner core particles containing a binder resin and a pigment are prepared and dispersed in an aqueous medium to obtain a core particle dispersion. At this time, the core particle concentration is preferably such that the solid content of the core particles is 10% by mass or more and 40% by mass or less with respect to the total amount of the core particle dispersion. The temperature of the core particle dispersion is preferably adjusted to 35° C. or higher. Further, it is preferable to adjust the pH of the core particle dispersion to a pH at which condensation of the organosilicon compound described below does not easily proceed. Since the pH at which the condensation of the organosilicon polymer is difficult to proceed differs depending on the substance, it is preferably within ±0.5 around the pH at which the reaction is most difficult to proceed.

On the other hand, it is preferable to use the organosilicon compound that has been hydrolyzed. For example, as a pretreatment of the organosilicon compound, hydrolysis may be carried out in a separate container. When the amount of the organosilicon compound is 100 parts by mass, the charge concentration for hydrolysis is preferably 40 parts by mass or more and 500 parts by mass or less of water from which ions have been removed, such as ion-exchanged water or RO water, and more preferably water. It is 100 mass parts or more and 400 mass parts or less.

The hydrolysis conditions are preferably pH 2 or more and 7 or less, temperature 15° C. or more and 80° C. or less, and time 30 minutes or more and 600 minutes or less.

By mixing the obtained hydrolyzate and the core particle dispersion and adjusting the pH to a value suitable for condensation (preferably 6 or more and 12 or less, or 1 or more and 3 or less, more preferably 8 or more and 12 or less), organic The silicon compound can be condensed to form a surface layer on the core particle surface of the toner. Condensation and surface layering are preferably carried out at 35° C. or higher for 60 minutes or longer. In addition, the surface macrostructure can be adjusted by adjusting the holding time at 35° C. or higher before adjustment to a pH suitable for condensation, and the time is preferably 3 minutes or more and 120 minutes or less.

It is believed that the above method reduces the reactive residues in the organosilicon polymer and increases the ratio of the —Si—O—Si— structure, thereby forming a strong network.

In the toner of the present invention, the content of the organosilicon polymer is preferably 0.5% by mass or more and 10.0% by mass or less. More preferably, it is 1.0% by mass or more and 7.0% by mass or less. When the content is within the above range, durability of the toner can be improved. The content of the organosilicon polymer is controlled by the type and amount of the organosilicon compound used to form the organosilicon polymer, the method of producing toner particles during the formation of the organosilicon polymer, reaction temperature, reaction time, reaction solvent and pH. can be done. A method for measuring the content of the organosilicon polymer will be described later.

In the toner of the present invention, the fixation rate of the organosilicon polymer is preferably 90.0% or more. If the fixation rate is in the upper range, peeling and detachment of the organosilicon polymer is small, and since it is not fused to members in the cartridge, streaks are improved throughout the durability. A method for measuring the fixation rate of the organosilicon polymer will be described later.

The organosilicon polymer is preferably a polymer having a partial structure represented by the following formula (R ^a T3).
R ^a —SiO _3/2 (R ^a T3)
(In the formula, R ^a represents a hydrocarbon group having 1 to 6 carbon atoms, an aryl group, or a structure represented by the following formula (i) or formula (ii).)

（式（ｉ）および（ｉｉ）において、＊はＲ^aＴ３構造中のＳｉ元素との結合部位を表し、式（ｉｉ）におけるＬは、アルキレン基またはアリーレン基を表す。）

(In formulas (i) and (ii), * represents a bonding site with the Si element in the R ^a T3 structure, and L in formula (ii) represents an alkylene group or an arylene group.)

Since the organosilicon polymer has the above partial structure, the charge on the surface of the toner flows quickly, and the charging rise of the toner is improved. As a result, the toner on the developing roller is supplied even immediately after the solid image is output, and the solid followability is improved.

Of the four valences of Si atoms in the above formula (R ^a T3), one is bonded to R ^a and the remaining three are bonded to O atoms. The O atom forms a state in which both of its two valences are bonded to Si, that is, a siloxane bond (Si--O--Si). Considering Si atoms and O atoms as an organosilicon polymer, since it has two Si atoms and three O atoms, it is expressed as —SiO _3/2 .

The presence of the siloxane-based polymer moiety —SiO _3/2 in the formula (R ^a T3) can be confirmed by ²⁹ Si-NMR measurement of the tetrahydrofuran-insoluble portion of the toner particles. The presence of the vinyl polymer moiety represented by formula (i) and formula (ii) can be confirmed by ¹³ C-NMR measurement of the tetrahydrofuran-insoluble portion of the toner particles.

A typical production example of the organosilicon polymer that can be used in the present invention is a method called a sol-gel method. The sol-gel method is a method in which a liquid raw material is used as a starting material, hydrolyzed and condensation-polymerized, and then gelated through a sol state, and is used in a method for synthesizing glass, ceramics, organic-inorganic hybrids, and nanocomposites. By using this production method, functional materials in various shapes such as surface layers, fibers, bulk bodies, and fine particles can be produced from the liquid phase at low temperatures.

Specifically, the organosilicon polymer present on the surface layer of the toner particles is preferably produced by hydrolysis and polycondensation of a silicon compound represented by alkoxysilane.

By providing the surface layer containing the organosilicon polymer on the toner particles, it is possible to obtain a toner with improved environmental stability, less deterioration in toner performance during long-term use, and excellent storage stability. .

Furthermore, the sol-gel method starts from a liquid and forms a material by gelling the liquid, so various microstructures and shapes can be produced. In particular, when the toner particles are produced in an aqueous medium, the particles are easily precipitated on the surface of the toner particles due to the hydrophilicity of the hydrophilic group such as the silanol group of the organosilicon compound. The fine structure and shape can be adjusted by the reaction temperature, reaction time, reaction solvent, pH, the type and amount of the organometallic compound, and the like.

The organosilicon polymer in the present invention is preferably obtained by condensation polymerization of an organosilicon compound having a structure represented by the following formula (Z).

（式（Ｚ）中、Ｒ₁は、炭素数が１以上６以下の炭化水素基、アリール基、又は下記式（ｉ）あるいは式（ｉｉ）で表される構造を表し、Ｒ₂、Ｒ₃及びＲ₄は、それぞれ独立して、ハロゲン原子、ヒドロキシ基、アセトキシ基、又は、アルコキシ基を表す。）

(In the formula (Z), R ₁ represents a hydrocarbon group having 1 to 6 carbon atoms, an aryl group, or a structure represented by the following formula (i) or formula (ii), and R ₂ and R ₃ and R ₄ each independently represent a halogen atom, a hydroxy group, an acetoxy group, or an alkoxy group.)

（式（ｉ）および（ｉｉ）において、＊はＺ構造中のＳｉ元素との結合部位を表し、式（ｉｉ）におけるＬは、アルキレン基またはアリーレン基を表す。）

(In formulas (i) and (ii), * represents a bonding site with the Si element in the Z structure, and L in formula (ii) represents an alkylene group or an arylene group.)

Hydrophobicity can be improved by the hydrocarbon group of R ₁ , and toner particles with excellent environmental stability can be obtained. In addition, an aryl group that is an aromatic hydrocarbon group such as a phenyl group can also be used as the hydrocarbon group. When the hydrophobicity of R ₁ is high, the variation in charge amount tends to increase in various environments. Therefore, in view of environmental stability, R ₁ is more preferably a hydrocarbon group having 1 to 3 carbon atoms. .

R ₂ , R ₃ and R ₄ are each independently a halogen atom, a hydroxy group, an acetoxy group, or an alkoxy group (hereinafter also referred to as a reactive group). These reactive groups are hydrolyzed, addition-polymerized and polycondensed to form a cross-linked structure, and a toner excellent in member contamination resistance and development durability can be obtained. It is preferably an alkoxy group, and more preferably a methoxy group or an ethoxy group, from the viewpoints of moderate hydrolyzability at room temperature and deposition and coating properties on the surface of the toner particles. Also, the hydrolysis, addition polymerization and condensation polymerization of R ₂ , R ₃ and R ₄ can be controlled by reaction temperature, reaction time, reaction solvent and pH.

To obtain the organosilicon polymer used in the present invention, an organosilicon compound having three reactive groups (R ₂ , R ₃ and R ₄ ) in one molecule excluding R ₁ in the above formula (Z) (hereinafter also referred to as trifunctional silane) may be used singly or in combination.

Examples of the above formula (Z) include the following.

Vinyltrimethoxysilane, Vinyltriethoxysilane, Vinyldiethoxymethoxysilane, Vinylethoxydimethoxysilane, Vinyltrichlorosilane, Vinylmethoxydichlorosilane, Vinylethoxydichlorosilane, Vinyldimethoxychlorosilane, Vinylmethoxyethoxychlorosilane, Vinyldiethoxychlorosilane, Vinyl Triacetoxysilane, Vinyldiacetoxymethoxysilane, Vinyldiacetoxyethoxysilane, Vinylacetoxydimethoxysilane, Vinylacetoxymethoxyethoxysilane, Vinylacetoxydiethoxysilane, Vinyltrihydroxysilane, Vinylmethoxydihydroxysilane, Vinylethoxydihydroxysilane, Vinyldimethoxysilane trifunctional vinylsilanes such as hydroxysilane, vinylethoxymethoxyhydroxysilane, vinyldiethoxyhydroxysilane; allyltrimethoxysilane, allyltriethoxysilane, allyldiethoxymethoxysilane, allylethoxydimethoxysilane, allyltrichlorosilane, allylmethoxysilane; dichlorosilane, allylethoxydichlorosilane, allyldimethoxychlorosilane, allylmethoxyethoxychlorosilane, allyldiethoxychlorosilane, allyltriacetoxysilane, allyldiacetoxymethoxysilane, allyldiacetoxyethoxysilane, allylacetoxydimethoxysilane, allylacetoxymethoxyethoxysilane, trifunctional allylsilanes such as allylacetoxydiethoxysilane, allyltrihydroxysilane, allylmethoxydihydroxysilane, allylethoxydihydroxysilane, allyldimethoxyhydroxysilane, allylethoxymethoxyhydroxysilane, allyldiethoxyhydroxysilane; p-styryltri Methoxysilane, Methyltrimethoxysilane, Methyltriethoxysilane, Methyldiethoxymethoxysilane, Methylethoxydimethoxysilane, Methyltrichlorosilane, Methylmethoxydichlorosilane, Methylethoxydichlorosilane, Methyldimethoxychlorosilane, Methylmethoxyethoxychlorosilane, Methyldiethoxy chlorosilane, methyltriacetoxysilane, methyldiacetoxymethoxysilane, methyldiacetoxyethoxysilane, methylacetoxydimethoxysilane, methylacetoxymethoxyethoxysilane, methylacetoxydiethoxysilane, trifunctional methylsilanes such as methyltrihydroxysilane, methylmethoxydihydroxysilane, methylethoxydihydroxysilane, methyldimethoxyhydroxysilane, methylethoxymethoxyhydroxysilane, methyldiethoxyhydroxysilane; ethyltrimethoxysilane, ethyltriethoxysilane, trifunctional ethylsilanes such as ethyltrichlorosilane, ethyltriacetoxysilane, ethyltrihydroxysilane; trifunctional such as propyltrimethoxysilane, propyltriethoxysilane, propyltrichlorosilane, propyltriacetoxysilane, propyltrihydroxysilane; trifunctional butylsilanes such as butyltrimethoxysilane, butyltriethoxysilane, butyltrichlorosilane, butyltriacetoxysilane, butyltrihydroxysilane; hexyltrimethoxysilane, hexyltriethoxysilane, hexyltrichlorosilane; , hexyltriacetoxysilane, hexyltrihydroxysilane; trifunctional phenylsilanes such as phenyltrimethoxysilane, phenyltriethoxysilane, phenyltrichlorosilane, phenyltriacetoxysilane, phenyltrihydroxysilane; Silane. The organosilicon compounds may be used alone or in combination of two or more.

As a result of hydrolytic polycondensation, the content of the organosilicon compound satisfying the formula (Z) is preferably 50 mol % or more, more preferably 60 mol % or more, in the organosilicon polymer.

Further, as a result of hydrolytic polycondensation, an organosilicon compound having the structure of the formula (Z) and an organosilicon compound having four reactive groups in one molecule (tetrafunctional silane), three reactions in one molecule A combination of an organosilicon compound having a group (trifunctional silane), an organosilicon compound having two reactive groups in one molecule (bifunctional silane), or an organosilicon compound having one reactive group (monofunctional silane) You may use the organosilicon polymer obtained by carrying out. Examples of organic silicon compounds that may be used in combination include the following. dimethyldiethoxysilane, tetraethoxysilane, hexamethyldisilazane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxy propyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3- Acryloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriemethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3 -aminopropyltriethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-chloropropyltrimethoxysilane Silane, 3-anilinopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, bis(triethoxysilylpropyl)tetrasulfide, trimethylsilyl chloride, triethylsilyl chloride, triisopropylsilyl chloride, t-butyldimethylsilyl chloride, N,N'-bis(trimethylsilyl)urea, N,O-bis(trimethylsilyl)trifluoroacetamide, trimethylsilyltrifluoromethanesulfonate, 1,3-dichloro-1 , 1,3,3-tetraisopropyldisiloxane, trimethylsilylacetylene, hexamethyldisilane, 3-isocyanatopropyltriethoxysilane, tetraisocyanatosilane, methyltriisocyanatosilane, vinyltriisocyanatosilane.

In the present invention, the surface layer containing the organosilicon polymer and the core portion are preferably in contact with each other without any gap. As a result, the occurrence of bleeding due to the resin component, release agent, etc. inside the toner particles is suppressed from the surface layer of the toner particles, and a toner excellent in storage stability, environmental stability and development durability can be obtained.

The surface layer may contain resins such as styrene-acrylic copolymer resins, polyester resins and urethane resins, various additives, and the like, in addition to the organosilicon polymer described above.

[Pigment]
The pigment of the present invention is preferably a surface-treated pigment having a basic site on its surface. Specifically, it is preferably a pigment containing an organic dye having a basic site (hereinafter also referred to as a "treatment agent") or a pigment having a basic functional group.

A pigment containing an organic dye (treatment agent) having a basic site can be obtained, for example, by mixing an organic dye (treatment agent) having a basic site with a pigment. A pigment having a basic functional group can be obtained, for example, by directly chemically modifying a pigment to partially basify it. Either mode may be used, but a pigment containing an organic dye (treatment agent) having a basic moiety is preferable because of ease of adjustment of the pKb of the pigment and ease of development into pigment species.

The organic dye (treatment agent) having a basic moiety in the invention preferably has a structure represented by the following formula (1). This structure is obtained by bonding a basic compound derived from an amino group to an organic dye via an alkyl group.

（式（１）中、Ｐは有機色素を示す。ｘは１または２であり、ｙは１以上４以下の値である。Ｒ¹、Ｒ²はそれぞれ独立に、水素原子、メチル基、エチル基、プロピル基、イソプロピル基、ブチル基、イソブチル基、ｔｅｒｔ－ブチル基、またはＲ¹およびＲ²が結合して複素環を形成するのに必要な基を示す。）

(In Formula (1), P represents an organic dye, x is 1 or 2, and y is a value of 1 or more and 4 or less. R ¹ and R ² each independently represent a hydrogen atom, a methyl group, an ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, or a group necessary for R ¹ and R ² to combine to form a heterocyclic ring.)

P is an organic dye, and preferably has a structure that can be adsorbed on the pigment. More preferably, P is an organic dye having a phthalocyanine skeleton or quinacridone skeleton. Specific examples include copper phthalocyanine, zinc phthalocyanine, 2,9-dimethylquinacridone, and quinacridone.

y is the average number of basic moieties bound to the organic dye (average per organic dye molecule), and is a value of 1 or more and 4 or less (preferably 2 or more and 4 or less).

R ¹ and R ² each independently represent a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or a structure in which R ¹ and R ² combine to form a 5-membered ring. However, it is preferable because steric hindrance is suppressed and the treatment agent is easily adsorbed. When R ¹ and R ² combine to form a heterocyclic ring, the ring structure may contain a nitrogen atom or an oxygen atom in addition to N in formula (2).

Specific examples of basic functional groups corresponding to —NR ¹ R ² in the above formula (1) include an amino group as a primary amine, and a monomethylamino group, a monoethylamino group and a monopropylamino group as a secondary amine. group, monoisopropylamino group, monobutylamino group, monoisobutylamino group, mono-tert-butylamino group, monopentylamino group, monohexylamino group, dimethylamino group as tertiary amine, diethylamino group, dipropylamino group , diisopropylamino group, dibutylamino group, diisobutylamino group, di-tert-butylamino group, dipentylamino group, dihexylamino group, methylethylamino group, methylpropylamino group, methylbutylamino group, ethylpropylamino group, ethylbutylamino group, pyrrolidinyl group, piperidinyl group, piperazinyl group, morpholino group, pyrrolyl group and the like.

As described above, the pigment having a structure derived from a basic compound may be a pigment having a basic functional group. The basic functional group is preferably represented by the following formula (2).

In formula (2), * represents a binding site with the pigment, and z is 1 or 2. R ³ and R ⁴ each independently represent a hydrogen atom, a linear or branched alkyl group, or R ³ and R ⁴ combine to form a heterocyclic ring (preferably having 3 to 6 carbon atoms) Indicate the required groups.

Preferred embodiments of R ³ and R ⁴ are the same as those of R ¹ and R ² above. The mode of the group corresponding to -NR ³ R ⁴ is also the same as the functional group corresponding to -NR ¹ R ² above.

A pigment having a basic functional group can be obtained, for example, by directly chemically modifying a pigment to partially basify it. As a specific method, a basified copper phthalocyanine can be obtained by reacting a phthalocyanine pigment with paraformaldehyde and phthalimide in concentrated sulfuric acid.

The pigment having a structure derived from a basic compound is preferably a pigment containing an organic dye (treatment agent) having a basic site. Pigments that can be used for the basic-treated pigment include conventionally known pigments listed below.

Examples of black pigments include carbon black.

Examples of yellow pigments include compounds represented by condensation pigments, isoindolinone compounds, anthraquinone compounds, azo metal complex methine compounds, and allylamide compounds. More specifically, for example, C.I. I. Pigment Yellow 3, 7, 10, 12, 13, 14, 15, 17, 23, 24, 60, 62, 74, 75, 83, 93, 94, 95, 99, 100, 101, 104, 108, 109, 110, 111, 117, 123, 128, 129, 138, 139, 147, 148, 150, 155, 166, 168, 169, 177, 179, 180, 181, 183, 185, 191:1, 191, 192, 193, 199 and the like.

Examples of magenta pigments include condensation pigments, diketopyrrolopyrrole compounds, anthraquinone compounds, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds. More specifically, for example, C.I. I. Pigment Red 2, 3, 5, 6, 7, 23, 48:2, 48:3, 48:4, 57:1, 81:1, 122, 146, 150, 166, 169, 177, 184, 185, 202, 206, 220, 221, 238, 254, 269, C.I. I. Pigment Violet 19 and the like.

Examples of cyan pigments include phthalocyanine compounds, derivatives of phthalocyanine compounds, anthraquinone compounds, basic dye lake compounds, and the like. More specifically, C.I. I. Pigment Blue 1, 7, 15, 15:1, 15:2, 15:3, 15:4, 60, 62, 66 and the like.

These pigments may be used singly or in combination of two or more and mixed with the treatment agent.

The content of the pigment is preferably 1.0% by mass or more and 15.0% by mass or less in the toner particles. More preferably, it is 3.0% by mass or more and 10.0% by mass or less.

The ratio of the content of the organosilicon polymer to the content of the pigment in the toner particles is preferably 0.20 or more and 1.00 or less. Within the above range, the adhesion of the organosilicon polymer to the core particles is enhanced, and peeling can be suppressed, so that contamination of the developing roller can be prevented. Therefore, chargeability is stabilized throughout durability. It is more preferably 0.30 or more and 0.80 or less.

In the present invention, the base number of the pigment is preferably 0.9 mgKOH/g or more and 3.0 mgKOH/g or less, more preferably 1.3 mgKOH/g or more and 2.5 mgKOH/g or less. If the base value is 0.9 mgKOH/g or more, the absolute amount of the treating agent is sufficient, so the dispersibility of the pigment is improved, and the coloring power is likely to be improved. Moreover, if it is 3.0 mgKOH/g or less, it is easy to improve durability and heat-resistant storage stability while maintaining sufficient coloring power. The base number of the basic treated pigment can be controlled by adjusting the amount of treatment agent added. The method for measuring the base number will be described later.

The method for producing the processing agent in the present invention is not particularly limited, and it can be obtained by a conventionally known method. Specifically, the manufacturing method example described in Japanese Patent No. 4484171 can be applied to the manufacturing method of the processing agent of the present invention.

[Binder resin]
The toner of the present invention contains a binder resin. The binder resin is not particularly limited, and conventionally known ones can be used. Preferred examples of the binder resin include vinyl-based resins and polyester resins. Examples of vinyl resins, polyester resins and other binder resins include the following resins or polymers.

Homopolymers of styrene and substituted products thereof such as polystyrene and polyvinyltoluene; styrene-propylene copolymers, styrene-vinyltoluene copolymers, styrene-vinylnaphthalene copolymers, styrene-methyl acrylate copolymers, styrene - ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-dimethylaminoethyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-methacrylic acid Ethyl copolymer, styrene-butyl methacrylate copolymer, styrene-dimethylaminoethyl methacrylate copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer Styrenic copolymers such as coalescence, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester copolymer; polymethyl methacrylate, polybutyl methacrylate, poly Vinyl acetate, polyethylene, polypropylene, polyvinyl butyral, silicone resin, polyamide resin, epoxy resin, polyacrylic resin, rosin, modified rosin, terpene resin, phenol resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin. These binder resins can be used alone or in combination.

In the present invention, the binder resin preferably contains a carboxyl group from the viewpoint of chargeability, and is preferably a resin produced using a polymerizable monomer containing a carboxyl group. (Meth)acrylic acids, such as α-ethylacrylic acid, crotonic acid, and α-alkyl or β-alkyl derivatives; unsaturated dicarboxylic acids, such as fumaric acid, maleic acid, citraconic acid, itaconic acid; monoacryloyl succinate; unsaturated dicarboxylic acid monoester derivatives such as oxyethyl ester, monoacryloyloxyethylene succinate, monoacryloyloxyethyl phthalate and monomethacryloyloxyethyl phthalate;

As the polyester resin, those obtained by condensation polymerization of the following carboxylic acid component and alcohol component can be used. Carboxylic acid components include terephthalic acid, isophthalic acid, phthalic acid, fumaric acid, maleic acid, cyclohexanedicarboxylic acid, and trimellitic acid. Alcohol components include bisphenol A, hydrogenated bisphenol, ethylene oxide adduct of bisphenol A, propylene oxide adduct of bisphenol A, glycerin, trimethylolpropane, and pentaerythritol.

Moreover, the polyester resin may be a polyester resin containing a urea group. As for the polyester resin, it is preferable not to cap carboxyl groups such as terminals.

In the toner of the present invention, the resin may have a polymerizable functional group for the purpose of improving the viscosity change of the toner at high temperatures. Polymerizable functional groups include vinyl groups, isocyanate groups, epoxy groups, amino groups, carboxyl groups, and hydroxy groups.

[Crosslinking agent]
In order to control the molecular weight of the binder resin constituting the toner particles, a cross-linking agent may be added during the polymerization of the polymerizable monomer.

For example, ethylene glycol dimethacrylate, ethylene glycol diacrylate, diethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol dimethacrylate, triethylene glycol diacrylate, neopentyl glycol dimethacrylate, neopentyl glycol diacrylate, divinylbenzene, bis(4 -acryloxypolyethoxyphenyl)propane, ethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-butanediol diacrylate, 1,5-pentanediol diacrylate, 1,6-hexanediol diacrylate, Neopentyl glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol #200, #400, #600 diacrylates, dipropylene glycol diacrylate, polypropylene glycol diacrylate, polyester type Diacrylates (MANDA, Nippon Kayaku), and methacrylates of the above acrylates.

The amount of the cross-linking agent to be added is preferably 0.001% by mass or more and 15.000% by mass or less based on the polymerizable monomer.

[About mold release agent]
In the present invention, it is preferable to contain a releasing agent as one of the materials constituting the toner particles. Examples of releasing agents that can be used for the toner particles include paraffin wax, microcrystalline wax, petroleum wax and its derivatives such as petrolatum, montan wax and its derivatives, hydrocarbon wax and its derivatives obtained by the Fischer-Tropsch process, polyethylene, Polyolefin waxes such as polypropylene and derivatives thereof, natural waxes such as carnauba wax and candelilla wax and derivatives thereof, higher aliphatic alcohols, fatty acids such as stearic acid and palmitic acid, or compounds thereof, acid amide waxes, ester waxes , ketones, hydrogenated castor oil and its derivatives, vegetable waxes, animal waxes, and silicone resins. Derivatives include oxides, block copolymers with vinyl-based monomers, and graft-modified products. The content of the release agent is preferably 5.0 parts by mass or more and 20.0 parts by mass or less with respect to 100.0 parts by mass of the binder resin or polymerizable monomer.

[Charge control agent]
In the present invention, the toner particles may contain a charge control agent. A known charge control agent can be used. In particular, a charge control agent that has a high charging speed and can stably maintain a constant charge amount is preferred. Furthermore, when the toner particles are produced by a direct polymerization method, a charge control agent which has a low polymerization inhibitory property and substantially no solubilized substances in an aqueous medium is particularly preferred.

Examples of charge control agents that control toner particles to be negatively chargeable include the following.

As organometallic compounds and chelate compounds, monoazo metal compounds, acetylacetone metal compounds, aromatic oxycarboxylic acids, aromatic dicarboxylic acids, oxycarboxylic acids and dicarboxylic acid metal compounds. Others include aromatic oxycarboxylic acids, aromatic mono- and polycarboxylic acids and their metal salts, anhydrides, or esters, phenol derivatives such as bisphenol, and the like. Furthermore, urea derivatives, metal-containing salicylic acid-based compounds, metal-containing naphthoic acid-based compounds, boron compounds, quaternary ammonium salts, and calixarenes are included.

On the other hand, examples of the charge control agent for controlling the toner particles to be positively charged include the following.

nigrosine and nigrosine modifications such as fatty acid metal salts; guanidine compounds; imidazole compounds; tributylbenzylammonium-1-hydroxy-4-naphthosulfonate; and their lake pigments; triphenylmethane dyes and their lake pigments (the lake agents include phosphotungstic acid, phosphomolybdic acid, phosphotungsten molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.); metal salts of higher fatty acids; resin charge control agents.

These charge control agents may be contained singly or in combination of two or more. The amount of these charge control agents to be added is preferably 0.01 parts by mass or more and 10.00 parts by mass or less with respect to 100.00 parts by mass of the binder resin.

[External additive]
The toner particles of the present invention can constitute the toner of the present invention without external additives. The toner of the present invention may be configured by adding an auxiliary agent or the like.

Examples of external additives include inorganic oxide fine particles such as silica fine particles, alumina fine particles and titanium oxide fine particles; inorganic stearic acid compound fine particles such as aluminum stearate fine particles and zinc stearate fine particles; Examples include fine particles of inorganic titanate compounds such as zinc oxide. These can be used individually by 1 type or in combination of 2 or more types. These inorganic fine particles are preferably gloss-treated with a silane coupling agent, a titanium coupling agent, a higher fatty acid, a silicone oil, or the like, in order to improve heat-resistant storage stability and environmental stability. The BET specific surface area of the external additive is preferably 10 m ² /g or more and 450 m ² /g or less.

The BET specific surface area can be determined by a low temperature gas adsorption method using a dynamic constant pressure method according to the BET method (preferably the BET multipoint method). For example, using a specific surface area measuring device (trade name: Gemini 2375 Ver.5.0, manufactured by Shimadzu Corporation), nitrogen gas is adsorbed on the surface of the sample, and the BET multipoint method is used for measurement. BET specific surface area (m ² /g) can be calculated.

The total amount of these external additives added is 0.05 parts by mass or more and 5 parts by mass or less, preferably 0.1 parts by mass or more and 3 parts by mass or less with respect to 100 parts by mass of the toner. In addition, various external additives may be used in combination.

[Developer]
The toner of the present invention can be used as a magnetic or non-magnetic one-component developer, but may be mixed with a carrier and used as a two-component developer.

As the carrier, magnetic particles made of conventionally known materials such as metals such as iron, ferrite and magnetite, and alloys of these metals with metals such as aluminum and lead can be used. is preferably used. As the carrier, a coated carrier in which the surfaces of magnetic particles are coated with a coating agent such as a resin, or a resin-dispersed carrier in which magnetic fine powder is dispersed in a binder resin may be used.
The carrier preferably has a volume average particle size of 15 μm or more and 100 μm or less, more preferably 25 μm or more and 80 μm or less.

[Method for producing toner particles]
The toner particles of the present invention can be produced by known means such as a kneading pulverization method or a wet production method. A wet production method can be preferably used from the viewpoint of uniformity of particle size and shape controllability. Furthermore, the wet production method includes a suspension polymerization method, a dissolution suspension method, an emulsion polymerization aggregation method, an emulsion aggregation method, and the like.

Here, the suspension polymerization method will be explained. In the suspension polymerization method, first, polymerizable monomers and pigments for synthesizing the binder resin are uniformly dissolved or dispersed using a dispersing machine such as a ball mill or an ultrasonic dispersing machine. A body composition is prepared (step of preparing a polymerizable monomer composition). At this time, if necessary, a polyfunctional monomer, a chain transfer agent, a wax as a release agent, a charge control agent, a plasticizer, and the like can be appropriately added.

As the polymerizable monomer in the suspension polymerization method, the following vinyl-based polymerizable monomers can be suitably exemplified. Styrene; α-methylstyrene, β-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p-tert-butylstyrene, p- Styrene derivatives such as n-hexylstyrene, pn-octyl, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, p-methoxystyrene, p-phenylstyrene; methyl acrylate, ethyl Acrylate, n-propyl acrylate, iso-propyl acrylate, n-butyl acrylate, iso-butyl acrylate, tert-butyl acrylate, n-amyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, n-nonyl Acrylic polymerizable monomers such as acrylate, cyclohexyl acrylate, benzyl acrylate, dimethyl phosphate ethyl acrylate, diethyl phosphate ethyl acrylate, dibutyl phosphate ethyl acrylate, 2-benzoyloxyethyl acrylate; methyl methacrylate, ethyl methacrylate, n- Propyl methacrylate, iso-propyl methacrylate, n-butyl methacrylate, iso-butyl methacrylate, tert-butyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, n-nonyl methacrylate, diethylphos methacrylic polymerizable monomers such as phosphate ethyl methacrylate and dibutyl phosphate ethyl methacrylate; methylene aliphatic monocarboxylic acid esters; vinyl acetate, vinyl propionate, vinyl benzoate, vinyl butyrate, vinyl benzoate, and vinyl formate vinyl ester; vinyl ether such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether; vinyl methyl ketone, vinyl hexyl ketone, vinyl isopropyl ketone.

Next, the polymerizable monomer composition is put into an aqueous medium prepared in advance, and droplets of the polymerizable monomer composition are formed by a stirrer or a disperser having a high shear force. core particle size (granulation step).

It is preferable that the aqueous medium in the granulation step contains a dispersion stabilizer in order to control the particle size of the core particles, sharpen the particle size distribution, and suppress coalescence of the core particles in the production process. Dispersion stabilizers are generally classified broadly into macromolecules that generate a repulsive force due to steric hindrance and poorly water-soluble inorganic compounds that stabilize dispersion by electrostatic repulsive force. Fine particles of poorly water-soluble inorganic compounds are preferably used because they are dissolved by acid or alkali and can be dissolved and easily removed by washing with acid or alkali after polymerization.

As the dispersion stabilizer for the sparingly water-soluble inorganic compound, one containing any one of magnesium, calcium, barium, zinc, aluminum and phosphorus is preferably used. More preferably, one of magnesium, calcium, aluminum and phosphorus is desired. Specifically, the following are mentioned.

Magnesium phosphate, tricalcium phosphate, aluminum phosphate, zinc phosphate, magnesium carbonate, calcium carbonate, magnesium hydroxide, calcium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate, hydroxyapatide.

Organic compounds such as polyvinyl alcohol, gelatin, methyl cellulose, methylhydroxypropyl cellulose, ethyl cellulose, sodium salts of carboxymethyl cellulose, and starch may be used in combination with the dispersion stabilizer. It is preferable to use 0.01 parts by mass or more and 2.00 parts by mass or less of these dispersion stabilizers with respect to 100 parts by mass of the polymerizable monomer. Furthermore, a surfactant of 0.001% by mass or more and 0.1% by mass or less may be used in combination to make these dispersion stabilizers finer. Specifically, commercially available nonionic, anionic, and cationic surfactants can be used. For example, sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, potassium stearate and calcium oleate are preferably used.

After the granulation step or while performing the granulation step, polymerization is generally performed at a temperature of 50° C. or higher and 90° C. or lower to obtain a core particle dispersion (polymerization step).

In the polymerization process, the temperature of the treatment liquid has a great effect on the fixing performance of the core particles. Therefore, the stirring operation is generally carried out so that the temperature distribution in the container becomes uniform. When a polymerization initiator is added, it can be added at any desired time and required time. Further, in order to obtain a desired molecular weight distribution, the temperature may be raised in the second half of the polymerization reaction, and further, in order to remove unreacted polymerizable monomers, by-products, etc. from the system, the second half of the reaction or the end of the reaction may be heated. Afterwards, a portion of the aqueous medium may be distilled off by a distillation operation. The distillation operation can be performed under normal pressure or reduced pressure.

An oil-soluble initiator is generally used as the polymerization initiator used in the suspension polymerization method. For example:

2,2'-azobisisobutyronitrile, 2,2'-azobis-2,4-dimethylvaleronitrile, 1,1'-azobis(cyclohexane-1-carbonitrile), 2,2'-azobis-4 - azo compounds such as methoxy-2,4-dimethylvaleronitrile; acetylcyclohexylsulfonyl peroxide, diisopropyl peroxycarbonate, decanonyl peroxide, lauroyl peroxide, stearoyl peroxide, propionyl peroxide, acetyl peroxide, tert- Butyl peroxy-2-ethylhexanoate, benzoyl peroxide, tert-butyl peroxyisobutyrate, cyclohexanone peroxide, methyl ethyl ketone peroxide, dicumyl peroxide, tert-butyl hydroperoxide, di-tert-butylperoxide peroxide initiators such as oxide, tert-butyl peroxypivalate and cumene hydroperoxide;

If necessary, a water-soluble initiator may be used in combination with the polymerization initiator, and examples thereof include the following.

ammonium persulfate, potassium persulfate, 2,2'-azobis(N,N'-dimethyleneisobutyroamidine) hydrochloride, 2,2'-azobis(2-aminodinopropane) hydrochloride, azobis(isobutylamidine) hydrochloride, sodium 2,2'-azobisisobutyronitrile sulfonate, ferrous sulfate or hydrogen peroxide.

These polymerization initiators can be used alone or in combination, and in order to control the degree of polymerization of the polymerizable monomer, a chain transfer agent, a polymerization inhibitor, etc. can be further added and used.
After the polymerization step, the surface layer containing the organosilicon polymer is formed as described above to obtain a toner particle dispersion (surface layer forming step).

Regarding the particle size of the toner particles in the present invention, the weight average particle size is preferably 3.0 μm or more and 10.0 μm or less from the viewpoint of obtaining a high-definition and high-resolution image. The weight average particle size of the toner can be measured by a pore electric resistance method. For example, it can be measured using "Coulter Counter Multisizer 3" (manufactured by Beckman Coulter, Inc.). The toner particle dispersion thus obtained is sent to a filtration step for solid-liquid separation of the toner particles and the aqueous medium.

Solid-liquid separation for obtaining toner particles from the obtained toner particle dispersion can be carried out by a general filtration method. It is preferable to carry out further washing, such as by spraying. After sufficient washing is performed, solid-liquid separation is performed again to obtain a toner cake. Thereafter, it is dried by a known drying means, and if necessary, is classified to separate a particle group having a particle size other than the predetermined one to obtain toner particles. The separated particle group having an irregular particle size may be reused in order to improve the final yield.

[Image forming apparatus]
An example of an image forming apparatus according to the present invention will be described below.

An image forming apparatus according to the present invention comprises a charging step of charging an image carrier using a charging member that contacts the image carrier, an electrostatic latent image forming step of forming an electrostatic latent image on the image carrier, and A development step of developing an electrostatic latent image with toner to form a toner image, a transfer step of transferring the toner image onto a recording medium via an intermediate transfer member, and the toner transferred onto the recording medium. An image forming apparatus having a process of heat-fixing an image. More specifically, as shown in FIG. 1, one having a so-called tandem type configuration in which electrophotographic stations of a plurality of colors are arranged side by side in the rotation direction of the intermediate transfer belt is preferably used. In the following description, suffixes Y, M, C, and k are attached to the reference numerals for the respective colors of yellow, magenta, cyan, and black, but the suffixes are omitted for similar configurations. sometimes.

In FIG. 1, charging devices 2Y, 2M, 2C and 2k, exposure devices 3Y, 3M and 3C, developing devices 4Y, 4M, 4C and 4k are provided around photosensitive drums (image carriers) 1Y, 1M, 1C and 1k. , an intermediate transfer belt (intermediate transfer member) 6 is arranged. The photosensitive drum 1 is rotationally driven in the direction of arrow F at a predetermined peripheral speed (process speed). The charging device 2 charges the peripheral surface of the photosensitive drum 1 to a predetermined polarity and potential (primary charging). A laser beam scanner as the exposure device 3 outputs a laser beam that is on/off modulated in accordance with image information input from an external device such as an image scanner (not shown) or a computer, thereby charging the photosensitive drum 1. The surface is scanned and exposed. This scanning exposure forms an electrostatic latent image on the surface of the photosensitive drum 1 according to the desired image information.

The developing devices 4Y, 4M, 4C, and 4k contain toners of yellow (Y), magenta (M), cyan (C), and black (k) color components, respectively. Then, the developing device 4 to be used is selected based on the image information, and developer (toner) is developed on the surface of the photosensitive drum 1 to visualize the electrostatic latent image as a toner image. In this embodiment, a reversal development method is used in which toner is adhered to the exposed portion of the electrostatic latent image for development. Further, the charging device, the exposure device, and the development device constitute electrophotographic means.

The intermediate transfer belt 6 is an endless belt, which is arranged so as to contact the surface of the photosensitive drum 1 and stretched over a plurality of tension rollers 20 , 21 and 22 . Then, it rotates in the direction of arrow G. In this embodiment, the tension roller 20 is a tension roller for controlling the tension of the intermediate transfer belt 6 to be constant, the tension roller 22 is a drive roller for the intermediate transfer belt 6, and the tension roller 21 is for secondary transfer. It is an opposing roller. Primary transfer rollers 5Y, 5M, 5C, and 5k are arranged at primary transfer positions facing the photosensitive drum 1 with the intermediate transfer belt 6 interposed therebetween.

The unfixed toner image of each color formed on the photosensitive drum 1 is transferred to the intermediate transfer belt by applying a primary transfer bias having a polarity opposite to that of the charged toner to the primary transfer roller 5 from a constant voltage source or a constant current source. 6 are electrostatically primary-transferred successively. Then, a full-color image is obtained on the intermediate transfer belt 6 by superposing unfixed toner images of four colors. The intermediate transfer belt 6 rotates while bearing the toner image transferred from the photosensitive drum 1 in this manner. After the primary transfer, the surface of the photosensitive drum 1 is cleaned of transfer residual toner by the cleaning device 11 each time the photosensitive drum 1 rotates, and the image forming process is repeated.

At the secondary transfer position of the intermediate transfer belt 6 facing the conveying path of the recording material 7 , a secondary transfer roller (transfer portion) 9 is placed in pressure contact with the toner image bearing surface of the intermediate transfer belt 6 . Further, on the back side of the intermediate transfer belt 6 at the secondary transfer position, a counter roller 21 serving as a counter electrode for the secondary transfer roller 9 and to which a bias is applied is arranged. When the toner image on the intermediate transfer belt 6 is transferred to the recording material 7, a bias having the same polarity as that of the toner is applied to the opposing roller 21 by the transfer bias applying means 28. For example, -1000 to -3000 V is applied to -10 A current of ~-50 μA flows. The transfer voltage at this time is detected by the transfer high voltage detection means 29 . Furthermore, a cleaning device (belt cleaner) 12 for removing toner remaining on the intermediate transfer belt 6 after the secondary transfer is provided downstream of the secondary transfer position.

The recording material 7 introduced to the secondary transfer position is nipped and conveyed at the secondary transfer position, and at that time, the opposing roller 21 of the secondary transfer roller 9 is controlled to a predetermined value by the secondary transfer bias applying means 28. A constant voltage bias (transfer bias) is applied. A transfer bias having the same polarity as that of the toner is applied to the opposing roller 21, thereby collectively transferring the four-color full-color image (toner image) superimposed on the intermediate transfer belt 6 onto the recording material 7 at the transfer portion. A full color unfixed toner image is formed thereon. The recording material 7 to which the toner image has been transferred is introduced into a fixing device (not shown) and heated and fixed.

<Structural analysis of treatment agent>
Determination of the structure of the treating agent and the average introduction amount of the basic site into the parent skeleton are performed by nuclear magnetic resonance spectroscopy ( ¹ H-NMR).
Measuring device: JNM-EX400 (manufactured by JEOL Ltd.)
Measurement frequency: 400MHz
Pulse condition: 5.0 μs
Frequency range: 10500Hz
Accumulation times: 1024 times Measurement solvent: DMSO-d6

Dissolve the sample as much as possible and measure under the above conditions. From the chemical shift value and proton ratio of the obtained spectrum, the structure of the treating agent and the average introduction amount to the matrix skeleton are calculated.

<Method for measuring base number and pKb of pigment>
The base number of a pigment is the number of mg of potassium hydroxide to the chemical equivalent of hydrochloric acid required to neutralize the acid contained in 1 g of sample. The base number of the pigment is measured according to the following procedure.

Titration is performed using a 0.1 mol/L hydrochloric acid ethanol solution. The above 0.1 mol/L hydrochloric acid is prepared according to JIS K 8001-1998.

Measurement conditions for base number measurement are shown below.
Titrator: potentiometric titrator AT-510 (manufactured by Kyoto Electronics Industry Co., Ltd.)
Electrode: Composite glass electrode double junction type (manufactured by Kyoto Electronics Industry Co., Ltd.)
Control software for titrator: AT-WIN
Titration analysis software: Tview
Titration parameters and control parameters at the time of titration are performed as follows.
Titration parameters Titration mode: blank titration Titration mode: whole volume titration Maximum titration volume: 20ml
Waiting time before titration: 30 seconds Titration direction: automatic control parameter Endpoint judgment potential: 30 dE
End point judgment potential value: 50 dE / dmL
End point detection judgment: Not set Control speed mode: Standard gain: 1
Data acquisition potential: 4 mV
Data collection titer volume: 0.1 ml

Main test;
200.0 g of a mixed solution of 10.0 g of pigment, 140.0 g of toluene and 60.0 g of ethanol (7:3) and 250 g of 0.8 mm glass beads are placed in a pressure-resistant container, and a paint shaker (manufactured by Toyo Seiki Seisakusho Co., Ltd.) is used. to obtain a pigment dispersion liquid. 100.0 g of this pigment dispersion is precisely weighed in a tall beaker.

Using the potentiometric titrator, the ethanol solution of hydrochloric acid is used for titration.

blank test;
Titration is performed in the same manner as described above, except that no sample is used (that is, only a mixed solution of 140.0 g of toluene and 60.0 g of ethanol is used).

Calculation of base number;
Substitute the obtained results into the following formula to calculate the base number.
BV=[(CB)×f×5.611]/S
(Wherein, BV: Base value (mgKOH/g), B: Added amount of hydrochloric ethanol solution for blank test (ml), C: Added amount of hydrochloric ethanol solution for main test (ml), f: Potassium hydroxide solution factor, S: sample (g).)

pKb determination;
The neutralization point is defined as the point where the slope of the pH change is greatest on the titration curve obtained during the measurement of the base number. The pKb of a pigment is determined as follows. The pH at half the amount of the 0.1 mol/l hydrochloric ethanol solution required to reach the neutralization point is read from the titration curve, and the read pH value is defined as pKb. However, if the base number is less than 0.1 and it is difficult to determine the neutralization point, the pH at the start of titration is taken as pKb.

<Organosilicon Polymer Amount in Toner>
The amount of organosilicon polymer in the toner was evaluated by the following method.

The amount of the organosilicon polymer was measured using a wavelength dispersive X-ray fluorescence spectrometer "Axios" (manufactured by PANalytical) and the attached dedicated software "SuperQ ver.4.0F" for setting measurement conditions and analyzing measurement data. (manufactured by PANalytical) is used. Rh is used as the anode of the X-ray tube, the measurement atmosphere is vacuum, the measurement diameter (collimator mask diameter) is 27 mm, and the measurement time is 10 seconds. A proportional counter (PC) is used to measure light elements, and a scintillation counter (SC) is used to measure heavy elements.

As a measurement sample, 4 g of toner particles were placed in a special aluminum ring for press, flattened, and compressed at 20 MPa and 60 using a tableting compressor "BRE-32" (manufactured by Mayekawa Test Instruments Co., Ltd.). A pellet molded to a thickness of 2 mm and a diameter of 39 mm by pressing for 2 seconds is used.

0.5 parts by mass of silica (SiO ₂ ) fine powder is added to 100 parts by mass of toner particles containing no organosilicon polymer, and the mixture is thoroughly mixed using a coffee mill. Similarly, 5.0 parts by mass and 10.0 parts by mass of fine silica powder are mixed with the toner particles, respectively, and these are used as samples for the calibration curve.

For each sample, a pellet of the sample for the calibration curve was prepared as described above using a tablet press, and when PET was used as the analyzing crystal, the diffraction angle (2θ) was observed at 109.08°. Measure the count rate (unit: cps) of Si-Kα rays. At this time, the acceleration voltage and current value of the X-ray generator are set to 24 kV and 100 mA, respectively. A linear function calibration curve is obtained with the obtained X-ray count rate on the vertical axis and the amount of SiO ₂ added in each calibration curve sample on the horizontal axis.

Next, the toner to be analyzed is made into pellets using a tablet press as described above, and the Si--Kα ray count rate of the pellets is measured. Then, the amount of the organosilicon polymer in the toner is determined from the above calibration curve.

<Method for Confirming Partial Structure Represented by Formula (R ^a T3)>
In the present invention, in the partial structure represented by the following formula (R ^a T3), the unit of the hydrocarbon group bonded to the silicon atom was confirmed by ¹³ C-NMR (solid state) measurement. Measurement conditions and sample preparation methods are shown below.
R ^a —SiO _3/2 (R ^a T3)
(In the formula, R ^a represents a hydrocarbon group having 1 to 6 carbon atoms, an aryl group, or a structure represented by the following formula (i) or formula (ii).

（式（ｉ）および（ｉｉ）において、＊はＲ^aＴ３構造中のＳｉ元素との結合部位を表し、式（ｉｉ）におけるＬは、アルキレン基またはアリーレン基を表す。）

(In formulas (i) and (ii), * represents a bonding site with the Si element in the R ^a T3 structure, and L in formula (ii) represents an alkylene group or an arylene group.)

" ¹³ C-NMR (solid) measurement conditions"
Device: JNM-ECX500II manufactured by JEOL RESONANCE
Sample tube: 3.2 mmφ
Sample: 150 mg of tetrahydrofuran-insoluble matter of toner particles for NMR measurement (preparation method below)
Measurement temperature: Room temperature Pulse mode: CP/MAS
Measurement nuclear frequency: 123.25 MHz ( ¹³ C)
Reference substance: adamantane (external standard: 29.5 ppm)
Sample rotation speed: 20 kHz
Contact time: 2ms
Delay time: 2s
Accumulated times: 1024 times

"Sample preparation method"
Preparation of measurement sample: 10.0 g of toner particles were weighed, placed in a filter paper thimble (No. 86R manufactured by Toyo Roshi Kaisha Ltd.), put in a Soxhlet extractor, and extracted with 200 ml of tetrahydrofuran as a solvent for 20 hours. was vacuum-dried at 40° C. for several hours to obtain a sample for NMR measurement.

In the present invention, when the above organic fine powder or inorganic fine powder is externally added to the toner, the organic fine powder or inorganic fine powder is removed by the following method to obtain toner particles.

160 g of sucrose (manufactured by Kishida Chemical Co., Ltd.) is added to 100 mL of ion-exchanged water and dissolved in a hot water bath to prepare a concentrated sucrose solution. In a centrifugation tube, 31 g of the concentrated sucrose solution, Contaminon N (a 10% by mass aqueous solution of a neutral detergent for cleaning precision measuring instruments at pH 7 consisting of a nonionic surfactant, an anionic surfactant, and an organic builder, (manufactured by Wako Pure Chemical Industries, Ltd.) is added to prepare a dispersion. 1.0 g of toner is added to this dispersion, and clumps of toner are loosened with a spatula or the like.

The centrifuge tube is shaken on a shaker at 350 spm (strokes per min) for 20 minutes. After shaking, the solution is replaced in a swing rotor glass tube (50 mL) and separated in a centrifuge at 3500 rpm for 30 minutes. This operation separates the toner particles from the detached external additive. It is visually confirmed that the toner and the aqueous solution are sufficiently separated, and the separated toner on the uppermost layer is collected with a spatula or the like. After filtering the collected toner with a vacuum filter, it is dried with a dryer for 1 hour or more to obtain toner particles. This operation is carried out multiple times to ensure the required amount.

In the above formula (R ^a T3), when R ^a is a partial structure represented by the above formula (i), depending on the presence or absence of a signal due to a methine group (>CH—Si) bonded to a silicon atom, the above The existence of the partial structure represented by the formula (R ^a T3) was confirmed.

In the above formula (R ^a T3), when R ^a is a partial structure represented by the above formula (ii), a methylene group (Si—CH ₂ —) or an ethylene group (Si—C ₂ H ₄ —) or other alkylene group or arylene group, such as a phenylene group (Si—C ₆ H ₄ —), confirms the existence of the unit represented by the above formula (R ^a T3). did.

In the above formula (R ^a T3), when R ^a is a partial structure represented by a hydrocarbon group having 1 to 6 carbon atoms or an aryl group, a methyl group (Si—CH ₃ ), ethyl group (Si—C ₂ H ₅ ), propyl group (Si—C ₃ H ₇ ), butyl group (Si—C ₄ H ₉ ), pentyl group (Si—C ₅ H ₁₁ ), hexyl group (Si —C ₆ H ₁₃ ) or an aryl group, such as a phenyl group (Si—C ₆ H ₅ —), confirmed the existence of the unit represented by the above formula (R ^a T3).

<Method for Measuring Peak Area Assigned to Structure of Formula (R ^a T3), Measured in ²⁹ Si-NMR of Tetrahydrofuran-Insoluble Content of Toner Particles>
In the present invention, the ²⁹ Si-NMR (solid) measurement of the tetrahydrofuran-insoluble portion of the toner particles was carried out under the following measurement conditions.

" ²⁹ Si-NMR (solid) measurement conditions"
Device: JNM-ECX500II manufactured by JEOL RESONANCE
Sample tube: 3.2 mmφ
Sample: 150 mg of tetrahydrofuran-insoluble matter of toner particles for NMR measurement (preparation method below)
Measurement temperature: Room temperature Pulse mode: CP/MAS
Measurement nuclear frequency: 97.38 MHz ( ²⁹ Si)
Reference substance: DSS (external standard: 1.534 ppm)
Sample rotation speed: 10 kHz
Contact time: 10ms
Delay time: 2s
Accumulated times: 2000 to 8000 times

After the above measurement, a plurality of silane components having different substituents and bonding groups in the tetrahydrofuran-insoluble portion of the toner particles were peak-separated into the following X1 structure, X2 structure, X3 structure, and X4 structure by curve fitting. Area was calculated.
X1 structure: (Ri) (Rj) (Rk) SiO _1/2 formula (12)
X2 structure: (Rg)(Rh)Si(O1 _/2 ) ₂ Formula (13)
X3 structure: RmSi(O _1/2 ) ₃ formula (14)
X4 structure: Si(O _1/2 ) ₄ formula (15)

（式（１２）乃至（１４）中のＲｉ、Ｒｊ、Ｒｋ、Ｒｇ、Ｒｈ、Ｒｍはケイ素原子に結合している有機基、ハロゲン原子、水酸基またはアルコキシ基を示す。）

(Ri, Rj, Rk, Rg, Rh, and Rm in formulas (12) to (14) represent an organic group bonded to a silicon atom, a halogen atom, a hydroxyl group, or an alkoxy group.)

In the present invention, a plurality of silane components having different substituents and bonding groups in the X3 structure were specified by chemical shift values in the chart obtained by ²⁹ Si-NMR measurement of the tetrahydrofuran-insoluble portion of the toner particles. These peaks were separated by curve fitting to obtain peak areas. The ratio of the peak area attributed to the structure of the formula (R ^a T3) to the total peak area of the organosilicon polymer was calculated by the above method.

When it is necessary to confirm the partial structure represented by the above formula (R ^a T3) in more detail, it is identified by the measurement results of ¹ H-NMR together with the measurement results of ¹³ C-NMR and ²⁹ Si-NMR. may

<Method for measuring fixation rate of organosilicon polymer>
160 g of sucrose (manufactured by Kishida Chemical Co., Ltd.) is added to 100 mL of ion-exchanged water and dissolved in a hot water bath to prepare a concentrated sucrose solution. In a centrifugation tube, 31 g of the concentrated sucrose solution, Contaminon N (a 10% by mass aqueous solution of a neutral detergent for cleaning precision measuring instruments at pH 7 consisting of a nonionic surfactant, an anionic surfactant, and an organic builder, (manufactured by Wako Pure Chemical Industries, Ltd.) is added to prepare a dispersion. 1 g of toner is added to this dispersion, and clumps of toner are loosened with a spatula or the like.

The tube for centrifugation is shaken with a shaker at 350 rpm for 20 minutes and washed with water. After shaking, the solution is replaced in a swing rotor glass tube (50 mL), and centrifuged at 3500 rpm for 30 minutes. It is visually confirmed that the toner and the aqueous solution are sufficiently separated, and the separated toner on the uppermost layer is collected with a spatula or the like. After the collected aqueous solution containing the toner is filtered with a vacuum filter, it is dried with a dryer for 1 hour or longer. The dried product is pulverized with a spatula, and the amount of the external additive is measured using fluorescent X-rays. The fixation rate (%) is calculated from the ratio of the amount of element to be measured between the toner after water washing and the initial toner.

Fluorescent X-ray measurement of each element conforms to JIS K 0119-1969, but is specifically as follows.

As a measurement device, a wavelength dispersive X-ray fluorescence spectrometer "Axios" (manufactured by PANalytical) and attached dedicated software "SuperQ ver.4.0F" (manufactured by PANalytical) for setting measurement conditions and analyzing measurement data ) is used. Rh is used as the anode of the X-ray tube, the measurement atmosphere is vacuum, the measurement diameter (collimator mask diameter) is 10 mm, and the measurement time is 10 seconds. A proportional counter (PC) is used to measure light elements, and a scintillation counter (SC) is used to measure heavy elements.

As a measurement sample, about 1 g of the toner after washing with water and the initial toner was placed in a dedicated press aluminum ring with a diameter of 10 mm, and the toner was flattened. ), pressurized at 20 MPa for 60 seconds, and used pellets molded to a thickness of about 2 mm.

Measurement is performed under the above conditions, the element is identified based on the obtained X-ray peak position, and the concentration is calculated from the count rate (unit: cps), which is the number of X-ray photons per unit time.

As a method for quantifying the amount of silicon in the toner, for example, silica (SiO ₂ ) fine powder is added to 100 parts by mass of toner particles so as to be 0.5 parts by mass, and the mixture is sufficiently mixed using a coffee mill. do. Similarly, 2.0 parts by mass and 5.0 parts by mass of fine silica powder are mixed with the toner particles, respectively, and these are used as samples for the calibration curve.

For each sample, a pellet of the sample for the calibration curve was prepared as described above using a tablet press, and when PET was used as the analyzing crystal, the diffraction angle (2θ) was observed at 109.08°. Measure the count rate (unit: cps) of Si-Kα rays. At this time, the acceleration voltage and current value of the X-ray generator are set to 24 kV and 100 mA, respectively. A linear function calibration curve is obtained with the obtained X-ray count rate on the vertical axis and the amount of SiO ₂ added in each calibration curve sample on the horizontal axis.

Next, the toner to be analyzed is made into pellets using a tablet press as described above, and the Si--Kα ray count rate of the pellets is measured. Then, the SiO ₂ content in the toner is obtained from the above calibration curve. The ratio of the elemental amount of the toner after washing with water to the elemental amount of the initial toner calculated by the above method was obtained and defined as the fixation rate (%). Elements other than silicon can also be determined in a similar manner by selecting calibration curve samples.

EXAMPLES The present invention will be specifically described below with reference to Examples, but the present invention is not limited to these Examples. All "parts" of each material in Examples and Comparative Examples are based on mass unless otherwise specified.

[Pigment production example]
A pigment was produced according to the production method described in Japanese Patent No. 4484171.

<Production of treatment agent 1>
91.4 parts of 98% by mass sulfuric acid, 36.7 parts of 25% by mass fuming sulfuric acid, 6.3 parts of diethylamine, 92% by mass of paraformaldehyde2. 8 parts were charged at 40°C. After stirring at 40° C. for 30 minutes, 8.0 parts of copper phthalocyanine was slowly added. After the addition, the temperature of the reaction solution was raised, and the reaction was carried out at 80° C. for 5 hours. After completion of the reaction, the reaction solution was cooled to room temperature, taken out into 750 parts of water, and the slurry was filtered, washed with water and dried to obtain a treatment agent 1 into which a diethylaminomethyl group was introduced.

NMR analysis of the resulting treatment agent 1 revealed that an average of 2.1 diethylaminomethyl groups had been introduced. Table 1 shows the physical properties of the treatment agent 1.

<Production of processing agents 2 to 7>
Treatment agents 2 to 7 shown in Table 1 were produced in the same manner as treatment agent 1, except that the structure and base skeleton of the amine compound were changed. In Table 1, CuPc in the structure indicates copper phthalocyanine, and Qd indicates 2,9-dimethylquinacridone.

<Production of Pigment 1>
C. I. To Pigment Blue 15:3 (100.0 parts) was added 2.0 parts of the treatment agent 1, and the mixture was shaken and mixed for 24 hours to prepare a basic treated pigment 1. Table 2 shows the physical properties of the obtained basic-treated pigment 1.

<Production of pigments 2 to 8>
Pigments 2 to 8 shown in Table 2 below were produced in the same manner as the production of Pigment 1, except that the type of treatment agent, the type of pigment and their mixing ratio were appropriately changed. Pigment type CB in Table 2 is carbon black.

[Example 1]
(Preparation step of aqueous medium 1)
To 1000.0 parts of ion-exchanged water in a reaction vessel, 14.0 parts of sodium phosphate (12 hydrate, manufactured by Rasa Kogyo Co., Ltd.) was added, and the mixture was kept at 65° C. for 1.0 hour while purging with nitrogen.

T. K. Using a homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), while stirring at 12000 rpm, a calcium chloride aqueous solution obtained by dissolving 9.2 parts of calcium chloride (dihydrate) in 10.0 parts of ion-exchanged water is mixed together. to prepare an aqueous medium containing a dispersion stabilizer. Furthermore, 10% by mass hydrochloric acid was added to the aqueous medium to adjust the pH to 6.0, and an aqueous medium 1 was obtained.

(Preparation step of polymerizable monomer composition)
・Styrene: 60.0 parts ・Pigment 1: 6.2 parts A pigment dispersion was prepared by time dispersion.

The following materials were added to the pigment dispersion.
・Styrene: 15.0 parts ・n-Butyl acrylate: 25.0 parts ・Crosslinking agent divinylbenzene: 0.3 parts ・Saturated polyester resin: 4.0 parts (propylene oxide-modified bisphenol A (2 mol adduct) and terephthal Polycondensate with acid (molar ratio 10:12), glass transition temperature Tg = 68 ° C., weight average molecular weight Mw = 10000, molecular weight distribution Mw / Mn = 5.12)
・Fischer-Tropsch wax (melting point 78°C): 9.0 parts

This was kept at 65° C. and T.I. K. A homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.) was used to uniformly dissolve and disperse at 500 rpm to prepare a polymerizable monomer composition.

(Hydrolysis step of organosilicon compound for surface layer)
60.0 parts of ion-exchanged water was weighed into a reactor equipped with a stirrer and a thermometer, and the pH was adjusted to 3.0 using 10% by mass hydrochloric acid. This was heated with stirring to bring the temperature to 70°C. Thereafter, 40.0 parts of methyltriethoxysilane was added and stirred for 2 hours to hydrolyze the organosilicon compound for the surface layer. The end point of the hydrolysis was visually confirmed by confirming that the oil and water did not separate and became one layer, and then cooled to obtain a hydrolyzate of the organosilicon compound for the surface layer.

(Granulation process)
While maintaining the temperature of the aqueous medium 1 at 70° C. and the rotation speed of the stirrer at 12000 rpm, the above polymerizable monomer composition was introduced into the aqueous medium 1, and t-butyl peroxypivalate 9 as a polymerization initiator. .0 parts were added. The mixture was granulated for 10 minutes while maintaining 12000 rpm with the stirring device.

(Polymerization, surface layer formation process)
The agitator was replaced with a propeller agitating blade from the high-speed agitator, and the polymerization reaction was carried out by maintaining the temperature at 70°C while stirring at 150 rpm for 5.0 hours and then heating the mixture to 95°C for 2.0 hours. to obtain a slurry of toner particles. After that, the temperature of the slurry was cooled to 60° C. and the pH was measured to be pH=5.0. While stirring was continued at 60° C., 25.0 parts of the hydrolyzate of the organosilicon compound for the surface layer was added to start forming the surface layer of the toner. After holding for 60 minutes as it is, the pH of the slurry was adjusted to 9.0 for completion of condensation using an aqueous sodium hydroxide solution and held for an additional 300 minutes to form a surface layer.

(Washing and drying process)
After completion of the polymerization process, the slurry of toner particles is cooled, and hydrochloric acid is added to the slurry of toner particles to adjust the pH to 1.5 or less, and the mixture is left with stirring for 1 hour, followed by solid-liquid separation with a pressurized filter to form a toner cake. got This was reslurried with ion-exchanged water to form a dispersion again, and then subjected to solid-liquid separation with the aforementioned filter. After reslurry and solid-liquid separation were repeated until the electrical conductivity of the filtrate became 5.0 μS/cm or less, solid-liquid separation was finally performed to obtain a toner cake. The resulting toner cake was dried with a flash jet dryer (manufactured by Seishin Enterprise Co., Ltd.). The drying conditions were a blowing temperature of 90.degree. C., a dryer outlet temperature of 40.degree.

In this example, the obtained toner particles 1 were used as the toner 1 as they were without being externally added. It was confirmed by the method described in the mode for carrying out the invention that Toner 1 contained an organosilicon polymer. Table 4 shows the physical properties of the obtained toner. The method for evaluating Toner 1 is described below. Table 5 shows the evaluation results.

<Evaluation of Toner Developability with Laser Beam Printer>
A commercially available Canon laser beam printer LBP7600C (a tandem-type full-color electrophotographic apparatus having an intermediate transfer belt) modified was used. The modifications were made by changing the gears and software of the main body of the evaluation machine so that the number of revolutions of the developing roller was twice that of the drum. The toner contained in the LBP7600C toner cartridge was removed, the inside was cleaned by an air blow, 50 g of toner was loaded, and the toner cartridge was set in the cyan station.

Under normal temperature and humidity (23° C., 60% RH), LETTER size XEROX4200 paper (manufactured by XEROX, 75 g/m ² ) was used as the image receiving paper, and 7,000 sheets of a 1% printing rate chart were continuously printed. I did.

After image formation, evaluation of transferability, evaluation of retransferability, evaluation of development streaks, evaluation of fogging, and evaluation of chargeability were performed. In the present invention, the effect of the present invention can be obtained with C or more.

(1) Evaluation of Transferability After image formation, a solid image was output under the condition that the development voltage was adjusted so that the amount of toner laid on the photoreceptor was 0.60 mg/cm ² . The untransferred toner was removed by taping with Mylar tape.

The difference in reflectance was calculated by subtracting the reflectance T0 of the stripped tape pasted on paper from the reflectance T1 of the stripped tape pasted on XEROX 4200 paper (manufactured by XEROX, 75 g/m ² ), and the reflectance T0 of the tape only pasted onto paper. Judgment was made as follows from the value of the reflectance difference. The reflectance was measured using a REFLECTMETER MODEL TC-6DS manufactured by Tokyo Denshoku Co., Ltd. A smaller value indicates better transferability.

(Evaluation criteria)
A: Reflectance difference is 2.0% or less B: Reflectance difference is more than 2.0% and 5.0% or less C: Reflectance difference is more than 5.0% and 10.0% or less D: Reflectance difference is 10 more than 0.0%

(2) Evaluation of Suppression of Retransfer First, a cartridge containing no toner was set in the black station, and a cartridge after image formation was set in the cyan station. Then, the developing voltage was adjusted so that the amount of toner applied on the photosensitive member was 0.60 mg/cm ² , and a solid image was output. The toner to be retransferred to the photoreceptor of the black station cartridge was then taped off with Mylar tape.

The difference in reflectance was calculated by subtracting the reflectance T0 of the stripped tape pasted on paper from the reflectance T1 of the stripped tape pasted on XEROX 4200 paper (manufactured by XEROX, 75 g/m ² ), and the reflectance T0 of the tape only pasted onto paper. Judgment was made as follows from the value of the reflectance difference. The reflectance was measured using a REFLECTMETER MODEL TC-6DS manufactured by Tokyo Denshoku Co., Ltd. The smaller the numerical value, the more the retransfer is suppressed.

(Evaluation criteria)
A: Reflectance difference is 2.0% or less B: Reflectance difference is more than 2.0% and 5.0% or less C: Reflectance difference is more than 5.0% and 10.0% or less D: Reflectance difference is 10 more than 0.0%

(3) Evaluation of development streaks Evaluation was made by the number of vertical streaks appearing on the development roller after image formation.

(Evaluation criteria)
A: No vertical streak is observed on the developing roller.
B: Three or less thin streaks in the circumferential direction are observed on both ends of the developing roller.
C: 4 or more and 10 or less thin circumferential streaks are observed on both ends of the developing roller.
D: 11 or more streaks are observed on the developing roller.

(4) Evaluation of Fog One sheet of solid white image was output after image formation, and fog was evaluated for the obtained solid white image. The fog density (%) was measured using "REFLECTMETER MODEL TC-6DS" (manufactured by Tokyo Denshoku Co., Ltd.), and the fog density ( %). As for the filter, an amber filter was used for the cyan toner.

(Evaluation criteria)
A: Less than 0.5% fog density B: 0.5% to less than 1.0% fog density C: 1.0% to less than 2.0% fog density D: 2.0% or more fog density

(5) Evaluation of chargeability Three solid black images are output after image output. The machine is forcibly stopped during the output of the third sheet, and the toner charge amount on the developing roller immediately after passing the regulation blade is measured. A Faraday cage shown in the perspective view of FIG. 2 was used to measure the amount of charge on the developing roller. The inside (on the right side of the figure) was depressurized so that the toner on the developing roller was sucked in, and a toner filter was provided to collect the toner. From the weight M of the collected toner and the charge Q directly measured with a coulomb meter, the charge amount Q/M (μC/g) per unit mass is calculated and defined as the toner charge amount (Q/M).

(Evaluation criteria)
A: Less than -30 μC/g B: -30 μC/g or more and less than -20 μC/g C: -20 μC/g or more and less than -10 μC/g D: -10 μC/g or more

[Examples 2 to 16, Comparative Examples 1 and 2]
In Example 1, the type and amount of the pigment in (the step of preparing the polymerizable monomer composition) and the type and amount of the organosilicon compound in the (step of hydrolyzing the organosilicon compound for the surface layer) were changed as shown in Table 3. A toner was produced in the same manner as in Example 1, except for the above. It was confirmed by the method described in the detailed description that the toner contained an organosilicon polymer. Table 4 shows the physical properties of the obtained toner, and Table 5 shows the evaluation results.

[Comparative Example 3]
In Example 1, the step of hydrolyzing the organosilicon compound for the surface layer was not performed. In the (polymerization step), the hydrolyzate was not added after the slurry of toner particles was obtained, and only pH adjustment and subsequent maintenance were performed. Toner particles 17 were produced in the same manner as in Example 1 except for the above.

To 100.0 parts of the above toner particles 17, 2.0 parts of untreated silica fine powder (trade name: Aerosil #200, specific surface area: about 200 m ² /g, manufactured by Aerosil Co., Ltd.) synthesized by a dry method was added in a Mitsui Henschel mixer. (Mitsui Miike Kakoki Co., Ltd.) at 3000 rpm for 15 minutes to obtain toner 17 . Table 4 shows the physical properties of the obtained toner, and Table 5 shows the evaluation results.

Claims (6)

A toner having toner particles containing a binder resin and a pigment (excluding the case where the toner particles contain a resin having an ionic functional group and a pKa of 6.0 or more and 9.0 or less) ,
the toner particles having a surface layer containing an organosilicon polymer;
the pigment contains an organic dye having a basic site,
The organic dye having a basic moiety has a structure represented by the following formula (1),

(In formula (1), P represents an organic dye. R ¹ and R ² each independently represent a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, or a tert-butyl represents a group, or represents a group necessary for R ¹ and R ² to combine to form a heterocyclic ring, x is 1 or 2, and y is a value of 1 or more and 4 or less.)
The pKb of the pigment is 3.0 or more and 7.0 or less .
A toner characterized by:
(The pKb is obtained by mixing 1.0 parts by mass of the pigment, 14.0 parts by mass of toluene and 6.0 parts by mass of ethanol, and dispersing the mixture together with 30.0 parts by mass of 0.8 mm glass beads with a paint shaker for 3 hours. is the pKb measured by the 0.1 mol/L HCl/EtOH neutralization test of the dispersion.
Accurately weigh 0.100 g of the resin having an ionic functional group and a pKa of 6.0 or more and 9.0 or less in a 250 mL tall beaker, add 150 mL of THF, dissolve over 30 minutes, and add a pH electrode to this solution. , read the pH of the THF solution of the sample, then add 10 μL of 0.1 mol / L potassium hydroxide ethyl alcohol solution at a time, read the pH each time, perform titration, pH becomes 10 or more, add 30 μL Add 0.1 mol/L potassium hydroxide ethyl alcohol solution until there is no change in pH, and plot the pH against the amount of 0.1 mol/L potassium hydroxide ethyl alcohol solution added from the obtained results to obtain a titration curve. The neutralization point is defined as the point where the slope of the pH change is greatest from the obtained titration curve. The pKa is the same value as the pH at half the amount of the 0.1 mol/L potassium hydroxide ethyl alcohol solution required up to the neutralization point, and the pH at half the amount is read from the titration curve. ) 2. The toner according to claim 1 , wherein the number of carbon atoms directly bonded to the silicon atoms of the organosilicon polymer is 1 or more and 3 or less. 3. The toner according to claim 1 , wherein the organosilicon polymer has a fixation rate of 90.0% or more. 4. The toner according to any one of claims 1 to 3, wherein the organosilicon polymer has a partial structure represented by the following formula (RaT3).
Ra—SiO _3/2 (RaT3)
(In formula (RaT3) , Ra represents a hydrocarbon group or aryl group having 1 to 6 carbon atoms, or a structure represented by formula (i) or (ii) below .)

(In formulas (i) and (ii) , * indicates a bonding site with the silicon atom in the partial structure represented by the formula ( RaT3) . In formula (ii) , L is an alkylene group or arylene indicates the group.) The toner according to any one of claims 1 to 4 , wherein the ratio of the content of the organosilicon polymer to the content of the pigment in the toner particles is 0.20 or more and 1.00 or less. . a charging step of charging the image carrier using a charging member in contact with the image carrier;
an electrostatic latent image forming step of forming an electrostatic latent image on the image carrier;
a developing step of developing the electrostatic latent image with toner to form a toner image;
a transfer step of transferring the toner image onto a recording medium via an intermediate transfer member; and
heat-fixing the toner image transferred onto the recording medium;
An image forming method comprising
The toner is the toner according to any one of claims 1 to 5 ,
An image forming method characterized by:

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