JP2019159253A - Toner for electrostatic latent image development, developer, toner storage unit, image forming apparatus, and image forming method - Google Patents

Abstract

To provide a toner for electrostatic latent image development that is excellent in electrostatic property, cleanability, and transferability, with which a good image can be formed, and is also excellent in emulsion stability during manufacture.SOLUTION: The above-mentioned problem is solved by a toner for electrostatic latent image development includes at least a binder resin, wax, colorant, and organic fine particles, wherein in the circularity distribution of the toner, particles having a circularity of 0.963 or more and 0.984 or less occupy 45.0 to 50.0% of the total toner.SELECTED DRAWING: Figure 6

Description

  The present invention relates to an electrostatic latent image developing toner, a developer, a toner containing unit, an image forming apparatus, and an image forming method.

  In electrophotographic image formation, an electrostatic charge image (latent image) is formed on an electrostatic latent image carrier, charged toner is conveyed by a developer carrier, and the latent image is developed to form a toner image. After the formation, the toner image is transferred onto a recording medium such as paper and fixed by a method such as heating to obtain an output image. Further, the toner remaining on the electrostatic latent image carrier after the transfer is collected from the electrostatic latent image carrier by the cleaning member and discharged to a waste toner storage unit.

In recent years, color image forming apparatuses using an electrophotographic method have become widespread, and in addition to the fact that digitized images can be easily obtained, further higher definition of printed images is desired. Has been.
Therefore, while higher resolution and gradation in the image are being studied, as an improvement on the toner side for visualizing the electrostatic latent image, in order to form a high-definition image, further spheroidization and smaller particle size are required. Consideration has been made.

  However, a polymerized toner having a small particle size and excellent circularity formed by a polymerization method or the like passes through between the cleaning member (cleaning blade) and the electrostatic latent image carrier, resulting in poor cleaning. There was a problem.

  Patent Document 1 discloses an image forming method using a toner having an adhesion force Fh (nN) to a plane of 15 ≦ Fh ≦ 50 and an adhesion force Fr (mN) between toner particles of 100 ≦ Fr ≦ 400. Is disclosed. According to the technique disclosed in Patent Document 1, an image having stable toner transferability, preventing reverse transfer of toner to the electrostatic latent image carrier, and further having excellent fixing performance and excellent image quality. It is said that a forming method can be provided.

  However, according to the study of the present inventor, in the technique disclosed in Patent Document 1, when the adhesion force Fh to the flat surface of the toner is set to 15 to 50 nN, the toner adhesion force on the electrostatic latent image carrier is increased. It has become a problem that the toner tends to remain on the electrostatic latent image carrier after cleaning. Further, when the adhesion force Fr (mN) between the toner particles is larger than 100, the transfer efficiency at the time of transfer is lowered and the void is likely to occur, and the cleaning failure on the electrostatic latent image carrier occurs. The problem was also found.

  Accordingly, an object of the present invention is to provide a toner for developing an electrostatic latent image that is excellent in charging property, cleaning property and transfer property, can form a good image, and is excellent in emulsion stability at the time of production.

The above problem is solved by the following configuration 1).
1) An electrostatic latent image developing toner comprising at least a binder resin, a wax, a colorant, and organic fine particles,
A toner for developing an electrostatic latent image, wherein particles having a circularity of 0.963 to 0.984 occupy 45.0 to 50.0% of the total toner in the circularity distribution of the toner.

  According to the present invention, it is possible to provide a toner for developing an electrostatic latent image that is excellent in chargeability, cleanability and transferability, can form a good image, and has excellent emulsification stability during production.

It is a figure for demonstrating one Embodiment of a process cartridge. 1 is a diagram for explaining an embodiment of an image forming apparatus of the present invention. It is a figure for demonstrating another embodiment of the image forming apparatus of this invention. It is a figure for demonstrating another embodiment of the image forming apparatus of this invention. It is a figure for demonstrating an image forming unit. 6 is an example of a graph showing a relationship between a residual ratio of toner (adhesion force between particles Fr) and an adhesion force Fh with respect to a plane. FIG. 3 is a conceptual diagram of an apparatus that obtains the adhesion force of toner to a flat surface.

Hereinafter, embodiments of the present invention will be described in detail.
The toner for developing an electrostatic latent image of the present invention is a toner for developing an electrostatic latent image containing at least a binder resin, a wax and a colorant, and having organic fine particles attached to the surface thereof. In the degree distribution, particles having a circularity of 0.963 or more and 0.984 or less occupy 45.0 to 50.0% of the whole toner.

  In the toner of the present invention, particles having a circularity of 0.963 or more and 0.984 or less in the circularity distribution account for 45.0 to 50.0% of the total toner. According to the study by the present inventor, the process of toner passing through the cleaning blade during cleaning was observed with a CCD microscope camera. As a result, the amount of particles having a circularity of 0.963 to 0.984 was controlled within a certain range. It was found that the toner was effective for slipping through the toner cleaning blade. That is, if the shape of the toner is too irregular, the flowability and charging performance of the toner will be hindered. Conversely, if it is too spherical, the amount of toner passing through the cleaning blade during cleaning will increase.

The circularity distribution of the toner can be obtained by measuring the average circularity of the toner.
As a method for measuring the average circularity, an optical detection band method is suitable in which a suspension containing particles is passed through an imaging unit detection band on a flat plate, and a particle image is optically detected and analyzed by a CCD camera. . The average circularity is a value obtained by dividing the perimeter of an equivalent circle having the same projected area obtained by this method by the perimeter of the actual particle.
This value is a value measured as an average circularity by a flow type particle image analyzer FPIA-3000S. As a specific measuring method, 0.1 to 0.5 ml of a surfactant, preferably an alkylbenzene sulfonate, is added as a dispersant to 100 to 150 ml of water from which impure solids have been removed in advance. About 0.1 to 0.5 g. The suspension in which the sample is dispersed is obtained by performing dispersion treatment for about 1 to 3 minutes with an ultrasonic disperser and measuring the shape and distribution of the toner with the above apparatus at a dispersion concentration of 3000 to 10,000 / μl. .
In the present invention, in the process of measuring the average circularity, the circularity distribution of the toner can be obtained by the flow type particle image analyzer FPIA-3000S.

In the present invention, in the circularity distribution of the toner, it is necessary that particles having a circularity of 0.963 or more and 0.984 or less occupy 45.0 to 50.0% of the whole toner. When the particles having a circularity of 0.963 or more and 0.984 or less are less than 45.0% of the total toner, the circularity distribution becomes broad, transfer efficiency is lowered during transfer, and voids are likely to occur. A cleaning failure occurs. On the other hand, if it exceeds 50.0%, the ratio of the indefinite formation is extremely reduced, so that blade scraping on the photoreceptor becomes insufficient, resulting in poor cleaning and the like. The proportion of the particles is based on the number of particles.
The particles having a circularity of 0.963 or more and 0.984 or less are preferably 46.0 to 49.0%, more preferably 47.0 to 48.0%, from the viewpoint of improving the effect of the present invention.

In the toner of the present invention, it is preferable that the adhesion force Fh (nN) to the plane satisfies the following formula 1 and the adhesion force between toner particles Fr (mN) satisfies the following formula 2.
3 ≦ Fh ≦ 15 (Formula 1)
50 ≦ Fr ≦ 100 (Formula 2)

In Formula 1, when the adhesion force Fh with respect to the flat surface of the toner is 3 nN or more, the adhesion force to the electrostatic latent image carrier becomes appropriate, and the occurrence of unevenness in the density of the image can be prevented. Further, when a transfer member such as an intermediate transfer belt is used, reverse transfer of toner to an electrostatic latent image carrier such as a photosensitive drum hardly occurs. Further, when the adhesion force Fh to the flat surface of the toner is 15 nN or less, the developability is improved.
When the adhesion force Fr between toner particles is 50 mN or more, scattering during transfer can be suppressed even when the toner adhesion amount is relatively large. When the adhesion force Fr between toner particles is 100 mN or less, even when the toner adhesion amount is relatively large, the transfer efficiency does not decrease during transfer, and the occurrence of voids can be prevented. By controlling these toner characteristics, it is possible to prevent the occurrence of image density unevenness, transfer loss, and color mixing, and it is possible to provide a toner having excellent chargeability, cleaning properties, and emulsion stability during production.

The toner of the present invention preferably satisfies the following formulas 3 and 4 and more preferably satisfies the following formulas 5 and 6 from the viewpoint of improving the effects of the present invention.
6 <Fh (nN) <12 (Formula 3)
60 <Fr (mN) <90 (Formula 4)
8 <Fh (nN) <10 (Formula 5)
70 <Fr (mN) <80 (Formula 6)

The adhesion force Fh with respect to the flat surface of the toner is determined by using a centrifugal adhesion measuring device (NS-C100 type: manufactured by Nano Seeds Co., Ltd.). The separation force which is separated is calculated and the 50% adhesion force obtained from this is calculated. An example of a toner residual ratio-adhesive force graph is shown in FIG. 6, and a conceptual diagram of an apparatus for determining the adhesive force on the flat surface of the toner is shown in FIG. 7 (m in FIG. 7 is mass).
Specifically, after toner is attached to the slide glass substrate, the slide glass substrate is fixed to the sample cell, and is measured at five levels of 2000 rpm, 4000 rpm, 6000 rpm, 12000 rpm, and 16000 rpm with a high-speed centrifuge. Centrifuge and record the toner separation. At this time, the separation force acting on the toner is calculated from the true toner specific gravity, particle diameter, rotation speed, and rotation radius. The toner residual ratio after rotation is measured with respect to the initial adhesion amount, the residual ratio is plotted on the horizontal axis, and the separation force is plotted on the vertical axis, and the separation force at which 50% of toner is separated from the approximate line (in this case, separation force) Is equivalent to the adhesive force) and is used as the adhesive force. The measurement environment was 23 ° C. and 50% (temperature and humidity).

The adhesion force Fh with respect to the flat surface of the toner was calculated as follows. The rotational angular velocity ω at which the residual ratio R of particles was 50% was calculated by the above-described measurement method, and the 50% adhesive force was calculated from the following equation (5).
Fh = (π / 6) · ρ · d ³ · r · ω ² Formula (5)
Here, ρ is the true particle density, d is the particle diameter, r is the rotational radius, and ω is the rotational angular velocity when the toner is separated by 50%. It should be noted that the adhesion force Fh with respect to the flat surface of the toner does not mean that the toner must be measured by the above-described model as long as it is obtained by the same principle as described above.

  Also, the adhesion force Fr between toner particles is a powder layer compression / tensile property measuring device (Ag Robot: manufactured by Hosokawa Micron Corporation), and 5 g of powder is filled in a cylindrical cell (inner diameter: 25 mm) divided into two upper and lower parts. The maximum tensile rupture force when the powder layer is broken by lifting the upper cell after holding the powder at 25 ° C. under a pressure of 8 kg. The spring wire diameter at this time was 1 mm, the compression speed was 0.02 mm / sec, the compression holding time was 300 sec, and the tensile speed was 0.6 mm / sec. It should be noted that the adhesion force Fr between the toner particles does not mean that the toner particles must be measured by the above model as long as it is obtained by the same principle as described above.

  According to the study of the present inventors, it has been found that the adhesion force Fh and the adhesion force Fr between toner particles with respect to the flat surface of the toner are closely related to the shape distribution of the toner. For example, the sharper the toner shape distribution, the smaller the adhesion force Fh to the toner plane. Further, the adhesion force Fh and the toner particle adhesion force Fr with respect to the flat surface of the toner can be adjusted by controlling the circularity distribution.

Conventionally, the circularity distribution of the toner has been controlled by the composition ratio of the oil phase component and the water phase component, the ratio of the two, etc., but the particle size is determined by converging the emulsified particles from the emulsification step (emulsification or dispersion). As the process proceeds to a step of granulating toner base particles having a narrow distribution, a problem has been found that the circularity distribution changes greatly.
Therefore, as a result of extensive studies, the present inventor dripped amine into the aqueous phase, and preferably, by dropping two types of amine component and alkali component into the aqueous phase, the hydrogen ion concentration was controlled within an arbitrary range. Thus, it is possible to achieve uniform toner particles and sharp shape distribution.

  More specifically, a composition containing a binder resin, a compound having an active hydrogen group, a polymer having a site capable of reacting with a compound having an active hydrogen group, a colorant, and a wax is dissolved in at least an organic solvent. Alternatively, after the dispersion or dispersion of the solution or dispersion in an aqueous medium, the compound having the active hydrogen group is reacted with the polymer having a site capable of reacting with the compound having the active hydrogen group. Alternatively, in the method of producing a toner obtained by removing the organic solvent while reacting, washing, and drying, the hydrogen ion concentration is adjusted by adding two types of amine compounds together with the basic aqueous solution during the production of the aqueous medium. By doing so, it is possible to control the circularity distribution of the toner, the adhesion force Fh to the toner plane and the adhesion force Fr between toner particles.

  Here, examples of the two kinds of amines include isophoronediamine and tertiary amine compounds, and it is preferable to combine these with a basic aqueous solution. As a measure of the amount of amine added, it is preferable to add two types of amine compounds in the range of 1 to 25% mol with respect to the estimated acid value of the reactant. This means that the amount of the two types of amine compounds to be added is determined in the range of 1 to 25% mol depending on the estimated acid value of the reactant. The estimated acid value (mgKOH / g) of the reaction product needs to be converted to mol / g, and if conversion formula = (0.001 gKOH / g) /56.1 is used, the acid value (mol) per gram is Calculated. Actually, since there is an appropriate hydrogen ion concentration range for emulsification and dispersion, the optimum ratio of the basic aqueous solution and the two types of amine compounds is preferably adjusted appropriately with a composition balance with other auxiliary materials. As described above, in the aqueous medium preparation process before reacting the compound having an active hydrogen group with the polymer having a site capable of reacting with the compound having the active hydrogen group, two types of amine compounds and a basic compound are used. After dropping the aqueous solution, the reaction is performed by mixing and dispersing the binder resin, the compound having an active hydrogen group, a polymer having a site capable of reacting with the compound having an active hydrogen group, a colorant, and a wax-containing oil phase. The reaction rate of the product is appropriately controlled, and a desired particle size distribution and shape distribution as a toner can be obtained. When the amine compound is mixed with a basic aqueous solution, it acts as a catalyst for the reaction between the compound having the active hydrogen group and the polymer having a site capable of reacting with the compound having the active hydrogen group, thereby stably promoting the reaction. it can.

  The tertiary amine compound added in the reaction step is premised on the addition to the granulated particle-water dispersion, and therefore needs to have water solubility, but the others are not particularly limited. Specifically, a tertiary amine catalyst or the like used in the synthesis of polyurethane is suitable from the viewpoint of safety and reaction rate improvement. Commercially available products can be used, for example, U-CAT660M (Ban (2-morpholino ethyl ether) manufactured by San Aho Pro, ZF-20 (manufactured by Huntsman), trimethylamine, etc.) The amount of the tertiary amine compound added Is preferably from 1 to 15% mol, more preferably from 3 to 10% mol, more preferably from 3 to 10% mol, based on the estimated acid value of the reactant. If it is 1% mol or more, the reaction rate is improved and the shape distribution of the toner is difficult to broaden. If it is 15% mol or less, the tertiary amine compound adsorbed on the toner surface can be easily removed, and the negative chargeability. There is no deterioration.

[Binder resin]
The binder resin contained in the toner of the present invention is not particularly limited, but preferably contains a crystalline resin and an amorphous resin, and specifically includes an amorphous polyester resin (preferably an amorphous modified polyester resin). ) And crystalline polyester resins are preferably used.
(Non-crystalline modified polyester resin)
In the present invention, the following modified polyester resins can be used as the polyester resin. For example, a polyester prepolymer having an isocyanate group can be used. Examples of the polyester prepolymer (A) having an isocyanate group include a product obtained by further reacting a polyester having an active hydrogen group with a polyisocyanate (3), which is a polycondensate of polyol (1) and polycarboxylic acid (2). Can be mentioned.
Examples of the active hydrogen group possessed by the polyester include hydroxyl groups (alcoholic hydroxyl groups and phenolic hydroxyl groups), amino groups, carboxyl groups, mercapto groups, and the like. Among these, alcoholic hydroxyl groups are preferred.

Examples of the polyol (1) include a diol (1-1) and a tri- or higher valent polyol (1-2). (1-1) alone or (1-1) and a small amount of (1-2) Mixtures are preferred.
Diol (1-1) includes alkylene glycol (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, etc.); alkylene ether glycol (diethylene glycol) , Triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.); alicyclic diols (1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.); bisphenols (bisphenol A, bisphenol) F, bisphenol S, etc.); alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adduct of the alicyclic diol; bisphenol And alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adducts. Among them, preferred are alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols, and particularly preferred are alkylene oxide adducts of bisphenols and alkylene glycols having 2 to 12 carbon atoms. It is a combined use. The trihydric or higher polyol (1-2) includes 3 to 8 or higher polyhydric aliphatic alcohols (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); trihydric or higher phenols (Trisphenol PA, phenol novolak, cresol novolak, etc.); and alkylene oxide adducts of the above trivalent or higher polyphenols.

Examples of the polycarboxylic acid (2) include dicarboxylic acid (2-1) and trivalent or higher polycarboxylic acid (2-2). (2-1) alone and (2-1) with a small amount of ( The mixture of 2-2) is preferred.
Dicarboxylic acid (2-1) includes alkylene dicarboxylic acid (succinic acid, adipic acid, sebacic acid, etc.); alkenylene dicarboxylic acid (maleic acid, fumaric acid, etc.); aromatic dicarboxylic acid (phthalic acid, isophthalic acid, terephthalic acid) And naphthalenedicarboxylic acid). Of these, preferred are alkenylene dicarboxylic acids having 4 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 20 carbon atoms. Examples of the trivalent or higher polycarboxylic acid (2-2) include aromatic polycarboxylic acids having 9 to 20 carbon atoms (trimellitic acid, pyromellitic acid, and the like). In addition, as polycarboxylic acid (2), you may make it react with polyol (1) using the acid anhydride or lower alkyl ester (methyl ester, ethyl ester, isopropyl ester, etc.) of the above-mentioned thing.

  The ratio of the polyol (1) and the polycarboxylic acid (2) is usually 2/1 to 1/1, preferably 1. as the equivalent ratio [OH] / [COOH] of the hydroxyl group [OH] and the carboxyl group [COOH]. 5/1 to 1/1, more preferably 1.3 / 1 to 1.02 / 1.

  As polyisocyanate (3), aliphatic polyisocyanate (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, etc.); alicyclic polyisocyanate (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.); aromatic Diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α, α, α ′, α′-tetramethylxylylene diisocyanate, etc.); isocyanurates; And a combination of two or more of these.

  The ratio of the polyisocyanate (3) is usually 5/1 to 1/1, preferably 4 /, as the equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester having a hydroxyl group. 1 to 1.2 / 1, more preferably 2.5 / 1 to 1.5 / 1. The content of the polyisocyanate (3) component in the prepolymer (A) having an isocyanate group at the terminal is usually 0.5 to 40% by mass, preferably 1 to 30% by mass, more preferably 2 to 20% by mass. It is.

  The number of isocyanate groups contained per molecule in the prepolymer (A) having an isocyanate group is usually 1 or more, preferably 1.5 to 3 on average, more preferably 1.8 to 2.5 on average. It is.

<Crosslinking agent and extender>
In the present invention, amines can be used as a crosslinking agent and / or an extender.
As amines (B), diamine (B1), trivalent or higher polyamine (B2), aminoalcohol (B3), aminomercaptan (B4), amino acid (B5), and amino acids B1-B5 blocked (B6) etc. are mentioned.
Examples of the diamine (B1) include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′dimethyldicyclohexylmethane, diaminecyclohexane, Isophorone diamine etc.); and aliphatic diamines (ethylene diamine, tetramethylene diamine, hexamethylene diamine etc.) and the like. Examples of the trivalent or higher polyamine (B2) include diethylenetriamine and triethylenetetramine. Examples of amino alcohol (B3) include ethanolamine and hydroxyethylaniline. Examples of amino mercaptan (B4) include aminoethyl mercaptan and aminopropyl mercaptan. Examples of the amino acid (B5) include aminopropionic acid and aminocaproic acid. Examples of the B1 to B5 amino group blocked (B6) include ketimine compounds and oxazoline compounds obtained from the B1 to B5 amines and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.). Among these amines (B), preferred are B1 and a mixture of B1 and a small amount of B2.

  Furthermore, if necessary, the molecular weight of the modified polyester after completion of the reaction can be adjusted by using a terminator for crosslinking and / or elongation. Examples of the terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.), and those blocked (ketimine compounds).

  The ratio of amines (B) is the equivalent ratio [NCO] / [NHx] of isocyanate groups [NCO] in the prepolymer (A) having isocyanate groups and amino groups [NHx] in amines (B). The ratio is usually 1/2 to 2/1, preferably 1.5 / 1 to 1 / 1.5, more preferably 1.2 / 1 to 1 / 1.2.

(Crystalline polyester resin)
The melting point of the crystalline polyester resin used in the present invention is preferably in the range of 50 to 100 ° C, more preferably in the range of 55 to 90 ° C, and still more preferably in the range of 60 to 85 ° C.
In addition, melting | fusing point of the said crystalline polyester resin is calculated | required as a peak temperature of the endothermic peak obtained by differential scanning calorimetry (DSC).

  In the present invention, “crystalline polyester resin” means a polymer (copolymer) obtained by polymerizing a component constituting a polyester and another component in addition to a polymer having a 100% polyester structure as a constituent component. To do. However, in the latter case, the component other than the polyester constituting the polymer (copolymer) is 50% by mass or less.

  The crystalline polyester resin used in the toner of the present invention is synthesized from, for example, a polyvalent carboxylic acid component and a polyhydric alcohol component. In the present embodiment, a commercially available product may be used as the crystalline polyester resin, or a synthesized product may be used.

Examples of the polyvalent carboxylic acid component used in the crystalline polyester resin include oxalic acid, succinic acid, glutaric acid, adipic acid, peric acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10- Aliphatic dicarboxylic acids such as decanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid; phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid Examples thereof include aromatic dicarboxylic acids of dibasic acids such as acid, malonic acid, and mesaconic acid, and examples thereof include, but are not limited to, anhydrides and lower alkyl esters thereof.
Examples of the trivalent or higher carboxylic acid include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, and the like, and anhydrides thereof. And lower alkyl esters. These may be used individually by 1 type and may use 2 or more types together.
Moreover, as an acid component, the dicarboxylic acid component which has a sulfonic acid group other than the said aliphatic dicarboxylic acid and aromatic dicarboxylic acid may be contained. Furthermore, in addition to the aliphatic dicarboxylic acid and aromatic dicarboxylic acid, a dicarboxylic acid component having a double bond may be contained.

  The polyhydric alcohol component used in the crystalline polyester resin is preferably an aliphatic diol, more preferably a linear aliphatic diol having a main chain portion having 7 to 20 carbon atoms. If the aliphatic diol is branched, the crystallinity of the polyester resin is lowered, and the melting point may be lowered. Further, when the main chain portion has less than 7 carbon atoms, when polycondensation with an aromatic dicarboxylic acid, the melting temperature becomes high and fixing at low temperature may be difficult, while the main chain portion has 20 carbon atoms. Exceeding the above range makes it difficult to obtain practical materials. The number of carbon atoms in the main chain portion is more preferably 14 or less.

Specific examples of the aliphatic diol suitably used for the synthesis of the crystalline polyester used in the toner of the present invention include ethylene glycol, 1,3-propanediol, 1,4-butanediol, and 1,5. -Pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12- Examples include, but are not limited to, dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, 1,14-eicosandecanediol, and the like. Among these, considering availability, 1,8-octanediol, 1,9-nonanediol, and 1,10-decanediol are desirable.
Examples of the trivalent or higher alcohol include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol and the like. These may be used individually by 1 type and may use 2 or more types together.

  Among the polyhydric alcohol components, the content of the aliphatic diol is preferably 80 mol% or more, and more preferably 90% or more.

  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; and alicyclic carboxylic acids such as cyclohexanedicarboxylic 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 acid value of the crystalline polyester resin used in the present invention (mg number of KOH required to neutralize 1 g of resin) is preferably in the range of 3.0 to 30.0 mgKOH / g, and 6.0 to 25 More desirably, it is in the range of 0.0 mgKOH / g, and further desirably in the range of 8.0 to 20.0 mgKOH / g.

  The crystalline polyester resin preferably has a weight average molecular weight (Mw) of 6,000 to 35,000. The weight average molecular weight can be measured by gel permeation chromatography (GPC). The molecular weight measurement by GPC was performed with a THF solvent using a Tosoh column / TSKgel Super HM-M (15 cm) using a Tosoh GPC / HLC-8120 as a measuring device. The weight average molecular weight is calculated from the measurement result using a molecular weight calibration curve prepared with a monodisperse polystyrene standard sample.

  The content of the crystalline polyester resin in the toner is preferably in the range of 3 to 40% by mass, more preferably in the range of 4 to 35% by mass, and still more preferably in the range of 5 to 30% by mass. .

[wax]
As the wax (release agent) used in the present invention, known ones can be used, for example, polyolefin wax (polyethylene wax, polypropylene wax, etc.); long chain hydrocarbon (paraffin wax, sasol wax, etc.); carbonyl Examples thereof include a group-containing wax. The content of the wax in the toner is usually 1 to 40% by mass, preferably 3 to 30% by mass.

[Colorant]
As the colorant in the present invention, all known dyes and pigments can be used. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide , Ocher, yellow lead, titanium yellow, polyazo yellow, oil yellow, Hansa yellow (GR, A, RN, R), pigment yellow L, benzidine yellow (G, GR), permanent yellow (NCG), Vulcan fast yellow ( 5G, R), Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL, Isoindolinone Yellow, Bengala, Red Dan, Lead Zhu, Cadmium Red, Cadmium Mercury Red, Antimon Zhu, Permanent Red 4R, Para Red , Phisa red, paracro Ortho Nitroaniline Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carnmin BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Tolujing Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, thioindigo red B, thioindigo maroon, oil red, quinacridone red, pyra Ron Red, Polyazo Red, Chrome Vermillion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indance Ren Blue (RS, BC), Indigo, Ultramarine Blue, Bitumen, Anthraquinone Blue, Fast Violet B, Methyl Violet Lake, Cobalt Purple, Manganese Purple, Dioxane Violet, Anthraquinone Violet, Chrome Green, Zinc Green, Chrome Oxide, Pyridian, Emerald Green , Pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Lakes, phthalocyanine greens, anthraquinone greens, titanium oxides, zinc whites, litbons and mixtures thereof can be used. The content of the colorant is usually 1 to 15% by mass, preferably 3 to 10% by mass with respect to the toner.

[Organic fine particles]
The organic fine particles used in the present invention are not particularly limited, and examples thereof include vinyl resins, polyurethane resins, epoxy resins, polyester resins, polyamide resins, polyimide resins, silicon resins, phenol resins, melamine resins, urea resins, anilines. Fine particles composed of a resin, an ionomer resin, a polycarbonate resin, and the like can be given. As the resin, two or more of the above resins may be used in combination.
In addition, the toner of the present invention is preferably one in which organic fine particles adhere to the surface from the viewpoint of its effect.
As a method for adhering organic fine particles to the toner surface, a method of stirring and mixing the toner and organic fine particles together with a known stirrer, a method of coating the organic fine particles on the toner surface and heat-sealing, or coating in the liquid Methods and the like.
The average particle size of the organic fine particles is, for example, preferably 5 nm to 200 nm, and more preferably 20 nm to 300 nm.
The amount of the organic fine particles contained in the toner is, for example, 0.5 to 5% by mass with respect to the toner, and preferably 1 to 3% by mass.

[Developer]
The developer of the present invention contains at least the toner and contains other components such as a carrier selected as appropriate. The developer may be a one-component developer or a two-component developer. However, when it is used for a high-speed printer or the like corresponding to the recent improvement in information processing speed, the life is improved. In view of the above, the two-component developer is preferable.

In the case of the one-component developer using the toner, toner agglomeration hardly occurs over time even against stress due to the developing means, and toner filming on the developing roller as the developer carrying member, The toner is not fused to a layer thickness regulating member such as a blade for reducing the thickness of the toner, and a good and stable image quality can be obtained by maintaining good image density stability and transferability.
In addition, in the case of the two-component developer using the toner, toner agglomeration is less likely to occur over time with respect to agitation stress by the developing unit, and the occurrence of abnormal images is suppressed and image density stability is achieved. In addition, by maintaining good transferability, good and stable image quality can be obtained.

<Career>
There is no restriction | limiting in particular as said carrier, Although it can select suitably according to the objective, What has a core particle and the resin layer (coating layer) which coat | covers this core particle is preferable.

<< Core particle >>
The core particles are not particularly limited as long as they are magnetic core particles, and can be appropriately selected according to the purpose. Examples thereof include ferromagnetic metals such as iron and cobalt; iron oxides such as magnetite, hematite and ferrite; and resin particles in which magnetic materials such as various alloys and compounds are dispersed in the resin. Among these, Mn-based ferrite, Mn-Mg-based ferrite, Mn-Mg-Sr-based ferrite and the like are preferable from the viewpoint of environmental considerations.

-Weight average particle diameter Dw of core particles-
The weight average particle diameter Dw of the core particles refers to the particle diameter at an integrated value of 50% in the particle size distribution of the core particles obtained by a laser diffraction or scattering method. There is no restriction | limiting in particular as the weight average particle diameter Dw of the said core particle, Although it can select suitably according to the objective, 10 micrometers-80 micrometers are preferable, and 20 micrometers-65 micrometers are more preferable.

The weight average particle diameter Dw of the core particles is measured by using a microtrac particle size distribution meter (HRA9320-X100, manufactured by Honeywell) as a particle diameter distribution (relationship between number frequency and particle diameter) of particles measured on a number basis. Measured under the conditions described below using the following formula (I). Each channel represents a length for dividing the particle size range in the particle size distribution chart into measurement width units, and the lower limit value of the particle size stored in each channel is adopted as the representative particle size.
Dw = {1 / Σ (nD ₃ )} × {Σ (nD ₄ )} (I)
However, in said formula (I), D represents the representative particle size (micrometer) of the core particle which exists in each channel, and n represents the total number of the core particle which exists in each channel.

[Measurement condition]
[1] Particle size range: 100 μm to 8 μm
[2] Channel length (channel width): 2 μm
[3] Number of channels: 46
[4] Refractive index: 2.42

<< Coating layer >>
The coating layer contains at least a resin, and may contain other components such as a filler as necessary.

-Resin-
There is no restriction | limiting in particular as resin for forming the coating layer of a carrier, According to the objective, it can select suitably. For example, a crosslinkable copolymer containing polyolefin (for example, polyethylene, polypropylene, etc.) or a modified product thereof, polystyrene, acrylic resin, acrylonitrile, vinyl acetate, vinyl alcohol, vinyl chloride, vinyl carbazole, vinyl ether, etc .; consisting of an organosiloxane bond Silicone resins or modified products thereof (for example, modified products by alkyd resin, polyester resin, epoxy resin, polyurethane, polyimide, etc.); polyamide; polyester; polyurethane; polycarbonate; urea resin; melamine resin; benzoguanamine resin; Examples thereof include polyimide resins and derivatives thereof. These may be used individually by 1 type and may use 2 or more types together. Among these, a silicone resin is preferable.

  There is no restriction | limiting in particular as said silicone resin, According to the objective, it can select suitably from the silicone resin generally known. For example, a straight silicone resin composed only of an organosiloxane bond, a silicone resin modified with alkyd, polyester, epoxy, acrylic, urethane, or the like can be used.

  Examples of the straight silicone resin include KR271, KR272, KR282, KR252, KR255, KR152 (manufactured by Shin-Etsu Chemical Co., Ltd.), SR2400, SR2405, SR2406 (manufactured by Toray Dow Corning Silicone).

  Specific examples of the modified silicone resin include epoxy-modified product: ES-1001N, acrylic-modified silicone: KR-5208, polyester-modified product: KR-5203, alkyd-modified product: KR-206, and urethane-modified product: KR-. 305 (manufactured by Shin-Etsu Chemical Co., Ltd.), epoxy-modified product: SR2115, alkyd-modified product: SR2110 (manufactured by Toray Dow Corning Silicone), and the like.

The silicone resin can be used alone, but a crosslinking reactive component, a charge amount adjusting component, and the like can be used at the same time.
Examples of the crosslinking reactive component include a silane coupling agent. Examples of the silane coupling agent include methyltrimethoxysilane, methyltriethoxysilane, octyltrimethoxysilane, aminosilane coupling agent, and the like.

-Filler-
There is no restriction | limiting in particular as said filler, According to the objective, it can select suitably, For example, a conductive filler, a nonelectroconductive filler, etc. are mentioned. These may be used individually by 1 type and may use 2 or more types together. Among these, it is preferable to contain a conductive filler and a non-conductive filler in the coating layer.

The conductive filler refers to a filler having a powder specific resistance value of 100 Ω · cm or less.
The said nonelectroconductive filler points out the filler whose powder specific resistance value exceeds 100 ohm * cm.
The powder specific resistance value of the filler is measured by a powder resistance measurement system (MCP-PD51, manufactured by Dia Instruments) and a resistivity meter (4-terminal 4-probe system, Loresta GP, manufactured by Mitsubishi Chemical Analytech). Can be measured under the conditions of a sample of 1.0 g, an electrode interval of 3 mm, a sample radius of 10.0 mm, and a load of 20 kN.

--Conductive filler--
There is no restriction | limiting in particular as said electroconductive filler, According to the objective, it can select suitably. For example, a conductive filler formed as a layer of tin dioxide or indium oxide on a substrate such as aluminum oxide, titanium oxide, zinc oxide, barium sulfate, silicon oxide, zirconium oxide, etc .; a conductive filler formed using carbon black, etc. It is done. Among these, a conductive filler containing aluminum oxide, titanium oxide, and barium sulfate is preferable.

--Non-conductive filler--
There is no restriction | limiting in particular as said nonelectroconductive filler, According to the objective, it can select suitably, For example, it forms using aluminum oxide, titanium oxide, barium sulfate, zinc oxide, silicon dioxide, zirconium oxide etc. Non-conductive filler etc. are mentioned. Among these, non-conductive fillers containing aluminum oxide, titanium oxide, and barium sulfate are preferable.

<< Carrier manufacturing method >>
There is no restriction | limiting in particular as a manufacturing method of the said carrier, Although it can select suitably according to the objective, The said resin and the said filler are contained in the surface of the said core particle using a fluid bed type coating apparatus. The method of manufacturing by apply | coating a coating layer forming solution is preferable. In addition, when apply | coating the said coating layer forming solution, you may advance condensation of the resin contained in the said coating layer, and after apply | coating the said coating layer forming solution, condensation of the resin contained in the said coating layer You may proceed. There is no restriction | limiting in particular as the condensation method of the said resin, According to the objective, it can select suitably, For example, the method etc. which give a heat | fever, light, etc. to the said coating layer formation solution, etc. are mentioned. .

-Weight average particle diameter Dw of carrier-
The weight average particle diameter Dw of the carrier refers to the particle diameter at an integrated value of 50% in the particle size distribution of the core particles obtained by a laser diffraction / scattering method. There is no restriction | limiting in particular as the weight average particle diameter Dw of the said carrier, Although it can select suitably according to the objective, 10 micrometers-80 micrometers are preferable, and 20 micrometers-65 micrometers are more preferable.

For the measurement of the weight average particle diameter Dw of the carrier, the particle size distribution (relationship between the number frequency and the particle diameter) of the particles measured on the basis of the number is used using a Microtrac particle size distribution meter (HRA9320-X100, manufactured by Honeywell). Measured under the conditions described below and calculated using the following formula (II). Each channel represents a length for dividing the particle size range in the particle size distribution chart into measurement width units, and the lower limit value of the particle size stored in each channel is adopted as the representative particle size.
Dw = {1 / Σ (nD ₃ )} × {Σ (nD ₄ )} (II)
However, in said formula (II), D represents the representative particle size (micrometer) of the carrier which exists in each channel, and n represents the total number of the carriers which exist in each channel.

[Measurement condition]
[1] Particle size range: 100 μm to 8 μm
[2] Channel length (channel width): 2 μm
[3] Number of channels: 46
[4] Refractive index: 2.42

  When the developer is a two-component developer, the mixing ratio of the toner and the carrier in the two-component developer is preferably such that the mass ratio of the toner to the carrier is 2.0 to 12.0% by mass, More preferably, it is 2.5-10.0 mass%.

[Toner storage unit]
The toner storage unit in the present invention refers to a unit in which toner is stored in a unit having a function of storing toner. Here, examples of the toner storage unit include a toner storage container, a developing device, and a process cartridge.
The toner container is a container that contains toner.
The developing device is a unit having a means for containing and developing toner.
The process cartridge is a cartridge in which at least the electrostatic latent image carrier and the developing unit are integrated, accommodates toner, and is detachable from the image forming apparatus. The process cartridge may further include at least one selected from charging means, exposure means, and cleaning means.

Next, an embodiment of the process cartridge is shown in FIG. As shown in FIG. 1, the process cartridge according to this embodiment includes an electrostatic latent image carrier 101, includes a charging device 102, a developing device 104, and a cleaning unit 107, and further includes other means as necessary. . In FIG. 2, reference numeral 103 denotes exposure from the exposure apparatus, and reference numeral 105 denotes recording paper.
As the electrostatic latent image carrier 101, the same one as an image forming apparatus described later can be used. An arbitrary charging member is used for the charging device 102.
An image forming process using the process cartridge shown in FIG. 1 will be described. The electrostatic latent image carrier 101 is rotated clockwise, and an electrostatic latent image corresponding to the exposure image is formed on the surface by charging by the charging device 102 and exposure 103 by an exposure unit (not shown). .
The electrostatic latent image is developed with toner by the developing device 104, and the toner development is transferred to the recording paper 105 by the transfer roller 108 and printed out. Next, the surface of the latent image carrier after the image transfer is cleaned by the cleaning unit 107 and further neutralized by a neutralizing unit (not shown), and the above operation is repeated again.

[Image Forming Method and Image Forming Apparatus]
The image forming method used in the present invention preferably includes a step of forming an image by a one-component developing method, and includes an electrostatic latent image forming step (charging step and exposure step), a developing step, a transfer step, and a fixing step. It includes a process and a cleaning process, and further includes other processes appropriately selected as necessary, for example, a static elimination process, a recycling process, a control process, and the like.
The image forming apparatus of the present invention includes an electrostatic latent image carrier, an electrostatic latent image forming unit (charging unit and exposure unit) that forms an electrostatic latent image on the electrostatic latent image carrier, and the electrostatic unit. Developing means for developing a latent image using a developer to form a visible image, transfer means for transferring the visible image onto a recording medium, and fixing for fixing the transferred image transferred onto the recording medium And cleaning means for removing the toner remaining on the electrostatic latent image carrier. Furthermore, other means appropriately selected as necessary, for example, a static elimination means, a recycling means, a control means and the like are provided.

-Electrostatic latent image forming step and electrostatic latent image forming means-
The electrostatic latent image forming step is a step of forming an electrostatic latent image on the electrostatic latent image carrier.
The electrostatic latent image carrier (sometimes referred to as “electrophotographic photosensitive member” or “photosensitive member”) is not particularly limited in terms of material, shape, structure, size, etc. It can be selected appropriately. The shape is preferably a drum shape, and examples of the material include inorganic photoreceptors such as amorphous silicon and selenium, and organic photoreceptors (OPC) such as polysilane and phthalopolymethine. Among these, an organic photoreceptor (OPC) is preferable in that a higher definition image can be obtained.

The formation of the electrostatic latent image can be performed, for example, by uniformly charging the surface of the electrostatic latent image carrier and then performing imagewise exposure, and is performed by electrostatic latent image forming means. Can do.
The electrostatic latent image forming unit includes, for example, a charging unit (charger) that uniformly charges the surface of the electrostatic latent image carrier, and an exposure that exposes the surface of the electrostatic latent image carrier imagewise. Means (exposure unit).

The charging can be performed, for example, by applying a voltage to the surface of the electrostatic latent image carrier using the charger.
The charger is not particularly limited and may be appropriately selected depending on the purpose. For example, a known contact charging device including a conductive or semiconductive roll, brush, film, rubber blade, etc. And non-contact chargers utilizing corona discharge such as corotrons and corotrons.
The charger is preferably one that is arranged in contact or non-contact with the electrostatic latent image carrier and charges the surface of the electrostatic latent image carrier by applying a direct current and an alternating voltage.
Further, the charger is a charging roller disposed in a non-contact proximity to the electrostatic latent image carrier via a gap tape, and the electrostatic latent image is carried by applying a direct current and an alternating voltage to the charging roller. Those that charge the body surface are preferred.

The exposure can be performed, for example, by exposing the surface of the latent electrostatic image bearing member imagewise using the exposure device.
The exposure device is not particularly limited as long as it can expose the surface of the latent electrostatic image bearing member charged by the charger so as to form an image to be formed, and is appropriately selected according to the purpose. For example, various exposure devices such as a copying optical system, a rod lens array system, a laser optical system, and a liquid crystal shutter optical system can be used.
In the present invention, a back light system in which imagewise exposure is performed from the back side of the electrostatic latent image carrier may be employed.

-Development process and development means-
The developing step is a step of developing the electrostatic latent image with the toner to form a visible image.
The visible image can be formed, for example, by developing the electrostatic latent image using the toner, and can be performed by the developing unit.
The developing unit preferably includes, for example, at least a developing unit that accommodates the toner and can apply the toner to the electrostatic latent image in a contact or non-contact manner, and includes a toner-containing container. Etc. are more preferable.

The developing device may be a monochromatic developing device or a multi-color developing device, and has, for example, an agitator that frictionally agitates and charges the toner and a rotatable magnet roller. A thing etc. are mentioned suitably.
In the developing unit, for example, the toner is mixed and agitated, and the toner is charged by friction at that time, and held on the surface of the rotating magnet roller in a raised state to form a magnetic brush. Since the magnet roller is disposed in the vicinity of the electrostatic latent image carrier (photoconductor), a part of the toner constituting the magnetic brush formed on the surface of the magnet roller is electrically attracted. It moves to the surface of the electrostatic latent image carrier (photoconductor) by force. As a result, the electrostatic latent image is developed with the toner, and a visible image is formed with the toner on the surface of the electrostatic latent image carrier (photoconductor).

-Transfer process and transfer means-
The transfer step is a step of transferring the visible image onto a recording medium. After the primary transfer of the visible image onto the intermediate transfer member using an intermediate transfer member, the visible image is transferred onto the recording medium. A primary transfer step of forming a composite transfer image by transferring a visible image onto an intermediate transfer body using two or more colors, preferably full color toner as the toner, and a composite transfer image; A mode including a secondary transfer step of transferring the transfer image onto the recording medium is more preferable.
The transfer can be performed, for example, by charging the latent electrostatic image bearing member (photoconductor) of the visible image using a transfer charger, and can be performed by the transfer unit. The transfer means includes a primary transfer means for transferring a visible image onto an intermediate transfer member to form a composite transfer image, and a secondary transfer means for transferring the composite transfer image onto a recording medium. Embodiments are preferred.
The intermediate transfer member is not particularly limited and may be appropriately selected from known transfer members according to the purpose. For example, a transfer belt and the like are preferable.

The transfer means (the primary transfer means and the secondary transfer means) is a transfer for peeling and charging the visible image formed on the electrostatic latent image carrier (photoconductor) to the recording medium side. It is preferable to have at least a vessel. The number of the transfer means may be one, or two or more.
Examples of the transfer device include a corona transfer device using corona discharge, a transfer belt, a transfer roller, a pressure transfer roller, and an adhesive transfer device.
The recording medium is not particularly limited and can be appropriately selected from known recording media (recording paper).

-Fixing process and fixing means-
The fixing step is a step of fixing the visible image transferred to the recording medium using a fixing device, and may be performed each time the developer of each color is transferred to the recording medium, or the developer of each color. On the other hand, it may be carried out at the same time in a state where these are laminated.
There is no restriction | limiting in particular as said fixing device, Although it can select suitably according to the objective, A well-known heating-pressing means is suitable. Examples of the heating and pressing means include a combination of a heating roller and a pressing roller, a combination of a heating roller, a pressing roller, and an endless belt.
The fixing device includes a heating body including a heating element, a film in contact with the heating body, and a pressure member in pressure contact with the heating body through the film, and the film and the pressure member It is preferably a unit that heats and fixes a recording medium on which an unfixed image is formed. The heating in the heating and pressing means is usually preferably 80 ° C to 200 ° C.
In the present invention, for example, a known optical fixing device may be used together with or in place of the fixing step and the fixing unit depending on the purpose.

-Cleaning process and cleaning means-
The cleaning step is a step of removing the toner remaining on the electrostatic latent image carrier and can be suitably performed by a cleaning unit.
The cleaning unit is not particularly limited, and may be selected from known cleaners as long as it can remove the toner remaining on the electrostatic latent image carrier. For example, a magnetic brush cleaner Suitable examples include electrostatic brush cleaners, magnetic roller cleaners, blade cleaners, brush cleaners, web cleaners, and the like.

-Other processes and other means-
The neutralization step is a step of performing neutralization by applying a neutralization bias to the electrostatic latent image carrier, and can be suitably performed by a neutralization unit.
The neutralization means is not particularly limited, and may be appropriately selected from known neutralizers as long as it can apply a neutralization bias to the electrostatic latent image carrier. Preferably mentioned.

The recycling step is a step of recycling the toner removed by the cleaning step to the developing unit, and can be suitably performed by the recycling unit. There is no restriction | limiting in particular as said recycling means, A well-known conveyance means etc. are mentioned.
The control step is a step of controlling each step, and each step can be suitably performed by a control means.
The control means is not particularly limited as long as the movement of each means can be controlled, and can be appropriately selected according to the purpose. Examples thereof include devices such as a sequencer and a computer.

  FIG. 2 shows a first example of the image forming apparatus of the present invention. The image forming apparatus 100 </ b> A includes a photosensitive drum 10, a charging roller 20, an exposure device, a developing device 40, an intermediate transfer belt 50, a cleaning device 60 having a cleaning blade, and a static elimination lamp 70.

  The intermediate transfer belt 50 is an endless belt stretched by three rollers 51 arranged on the inner side, and can move in the direction of the arrow in the figure. A part of the three rollers 51 also functions as a transfer bias roller that can apply a transfer bias (primary transfer bias) to the intermediate transfer belt 50. Further, a cleaning device 90 having a cleaning blade is disposed in the vicinity of the intermediate transfer belt 50. Further, a transfer roller 80 capable of applying a transfer bias (secondary transfer bias) for transferring the toner image to the transfer paper 95 is disposed opposite to the intermediate transfer belt 50. Further, around the intermediate transfer belt 50, a corona charging device 58 for applying a charge to the toner image transferred to the intermediate transfer belt 50 is connected to the photosensitive drum 10 with respect to the rotation direction of the intermediate transfer belt 50. It is disposed between the contact portion of the intermediate transfer belt 50 and the contact portion of the intermediate transfer belt 50 and the transfer paper 95.

  The developing device 40 includes a developing belt 41 and a black developing unit 45K, a yellow developing unit 45Y, a magenta developing unit 45M, and a cyan developing unit 45C provided around the developing belt 41. Each color developing unit 45 includes a developer container 42, a developer supply roller 43, and a developing roller (developer carrier) 44. The developing belt 41 is an endless belt stretched by a plurality of belt rollers, and can move in the direction of the arrow in the figure. Further, a part of the developing belt 41 is in contact with the photosensitive drum 10.

  Next, a method for forming an image using the image forming apparatus 100A will be described. First, the charging roller 20 is used to uniformly charge the surface of the photosensitive drum 10, and then the exposure light L is exposed to the photosensitive drum 10 using an exposure device (not shown) to form an electrostatic latent image. Form. Next, the electrostatic latent image formed on the photosensitive drum 10 is developed with the toner supplied from the developing device 40 to form a toner image. Further, after the toner image formed on the photosensitive drum 10 is transferred (primary transfer) onto the intermediate transfer belt 50 by the transfer bias applied from the roller 51, the transfer bias applied from the transfer roller 80 is used. Then, it is transferred (secondary transfer) onto the transfer paper 95. On the other hand, the photosensitive drum 10 on which the toner image is transferred to the intermediate transfer belt 50 is discharged by the discharging lamp 70 after the toner remaining on the surface is removed by the cleaning device 60.

  FIG. 3 shows a second example of the image forming apparatus used in the present invention. In the image forming apparatus 100B, the black developing unit 45K, the yellow developing unit 45Y, the magenta developing unit 45M, and the cyan developing unit 45C are arranged directly facing each other around the photosensitive drum 10 without providing the developing belt 41. Other than that, the configuration is the same as that of the image forming apparatus 100A.

  FIG. 4 shows a third example of the image forming apparatus used in the present invention. The image forming apparatus 100 </ b> C is a tandem type color image forming apparatus, and includes a copying apparatus main body 150, a paper feed table 200, a scanner 300, and an automatic document feeder (ADF) 400.

  The intermediate transfer belt 50 provided at the center of the copying apparatus main body 150 is an endless belt stretched around three rollers 14, 15 and 16, and can move in the direction of the arrow in the figure. In the vicinity of the roller 15, a cleaning device 17 having a cleaning blade for removing toner remaining on the intermediate transfer belt 50 on which the toner image has been transferred onto the recording paper is disposed. The image forming units 120Y, 120C, 120M, and 120K for yellow, cyan, magenta, and black are juxtaposed along the conveyance direction while facing the intermediate transfer belt 50 stretched by the rollers 14 and 15.

  An exposure device 21 is disposed in the vicinity of the image forming unit 120. Further, the secondary transfer belt 24 is disposed on the side of the intermediate transfer belt 50 opposite to the side on which the image forming unit 120 is disposed. The secondary transfer belt 24 is an endless belt stretched around a pair of rollers 23, and the recording paper and the intermediate transfer belt 50 conveyed on the secondary transfer belt 24 are between the rollers 16 and 23. Can touch.

  Further, in the vicinity of the secondary transfer belt 24, a fixing device 25 is provided with a fixing belt 26 that is an endless belt stretched between a pair of rollers, and a pressure roller 27 that is arranged to be pressed against the fixing belt 26. Is arranged. A sheet reversing device 28 for reversing the recording paper when an image is formed on both sides of the recording paper is disposed in the vicinity of the secondary transfer belt 24 and the fixing device 25.

Next, a method for forming a full-color image using the image forming apparatus 100C will be described. First, a color document is set on the document table 130 of the automatic document feeder (ADF) 400, or the automatic document feeder 400 is opened and a color document is set on the contact glass 32 of the scanner 300 to automatically convey the document. The device 400 is closed.
When the start switch is pressed, when an original is set on the automatic document feeder 400, after the original is conveyed and moved onto the contact glass 32, on the other hand, when the original is set on the contact glass 32, Immediately, the scanner 300 is driven, and the first traveling body 33 including the light source and the second traveling body 34 including the mirror travel. At this time, the reflected light from the original surface of the light irradiated from the first traveling body 33 is reflected by the second traveling body 34 and then received by the reading sensor 36 via the imaging lens 35, whereby the original is received. It is read and image information of black, yellow, magenta and cyan is obtained.

The image information for each color is transmitted to the image forming unit 120 for each color, and a toner image for each color is formed. As shown in FIG. 5, each color image forming unit 120 includes a photosensitive drum 10, a charging roller 160 that uniformly charges the photosensitive drum 10, and the image information of each color, respectively. An exposure device that exposes the exposure light L to form an electrostatic latent image of each color; a developing device 61 that develops the electrostatic latent image with a developer of each color to form a toner image of each color; A transfer roller 62 for transferring onto the transfer belt 50, a cleaning device 63 having a cleaning blade, and a static elimination lamp 64 are provided.
The toner images of the respective colors formed by the image forming units 120 of the respective colors are sequentially transferred (primary transfer) onto the intermediate transfer body 50 that is stretched and moved by the rollers 14, 15, and 16, and superimposed to form a composite toner image. It is formed.

  On the other hand, in the paper feed table 200, one of the paper feed rollers 142 is selectively rotated to feed recording paper from one of the paper feed cassettes 144 provided in multiple stages in the paper bank 143, and one sheet at a time by the separation roller 145. The paper is separated and sent to the paper feed path 146, transported by the transport roller 147, guided to the paper feed path 148 in the copying machine main body 150, and abutted against the registration roller 49 to stop. Alternatively, the paper feed roller is rotated to feed out the recording paper on the manual feed tray 54, separated one by one by the separation roller 52, guided to the manual paper feed path 53, and abutted against the registration roller 49 and stopped. The registration roller 49 is generally used while being grounded, but may be used in a state where a bias is applied in order to remove paper dust from the recording paper.

  Next, by rotating the registration roller 49 in synchronization with the composite toner image formed on the intermediate transfer belt 50, the recording paper is sent between the intermediate transfer belt 50 and the secondary transfer belt 24, and the composite toner image is sent. The toner image is transferred onto the recording paper (secondary transfer). The toner remaining on the intermediate transfer belt 50 to which the composite toner image has been transferred is removed by the cleaning device 17.

  The recording paper on which the composite toner image has been transferred is conveyed by the secondary transfer belt 24 and then the composite toner image is fixed by the fixing device 25. Next, the conveyance path of the recording paper is switched by the switching claw 55 and the recording paper is discharged onto the paper discharge tray 57 by the discharge roller 56. Alternatively, the recording path of the recording paper is switched by the switching claw 55, reversed by the sheet reversing device 28, an image is similarly formed on the back side, and then discharged onto the discharge tray 57 by the discharge roller 56. .

EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further more concretely, this invention is not limited by these examples.
Hereinafter, “parts” and “%” indicate parts by mass and mass% unless otherwise specified. First, analysis and evaluation methods for the toners obtained in Examples and Comparative Examples will be described.
In the following, the case of using the toner of the present invention as a two-component developer was evaluated. However, the toner of the present invention can also be used as a one-component developer.

<Measurement method>
The measuring methods of various physical properties measured in the following examples are described below.
(Average particle size)
Next, a method for measuring the particle size distribution of toner particles will be described.
As an apparatus for measuring the particle size distribution of toner particles by the Coulter counter method, there are Coulter Counter TA-II and Coulter Multisizer II (both manufactured by Coulter). The measurement method is as follows.
First, 0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 100 to 150 ml of an aqueous electrolytic solution. Here, the electrolytic solution is a solution prepared by preparing a 1% NaCl aqueous solution using first grade sodium chloride. For example, ISOTON-II (manufactured by Coulter) can be used. Here, 2 to 20 mg of the measurement sample is further added as a solid content.
The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the measurement device is used to measure the volume and number of toner particles or toner using a 100 μm aperture as an aperture. Volume distribution and number distribution are calculated. From the obtained distribution, the volume average particle diameter (Dv) and the number average particle diameter (Dn) of the toner can be obtained.
As a channel, for example, less than 2.00 to 2.52 μm; less than 2.52 to 3.17 μm; 3.17 to less than 4.00 μm; 4.00 to less than 5.04 μm; 5.04 to less than 6.35 μm; 6.35 to less than 8.00 μm; 8.00 to less than 10.08 μm; 10.08 to less than 12.70 μm; 12.70 to less than 16.00 μm; 16.00 to less than 20.20 μm; Less than .40 μm; 25.40 to less than 32.00 μm; 13 channels of 32.00 to less than 40.30 μm are used, and particles having a particle size of 2.00 μm to less than 40.30 μm can be targeted.

(Molecular weight)
The molecular weight was measured by normal GPC (gel permeation chromatography) under the following conditions.
・ Device: HLC-8220GPC (manufactured by Tosoh Corporation)
Column: TSKgel SuperHZM-M x 3
・ Temperature: 40 ℃
・ Solvent: THF (tetrahydrofuran)
・ Flow rate: 0.35 ml / min ・ Sample: 0.01 ml injection of a sample with a concentration of 0.05 to 0.6% Molecular weight calibration curve prepared from a monodisperse polystyrene standard sample from the molecular weight distribution of the toner resin measured under the above conditions Was used to calculate the weight average molecular weight Mw. As monodisperse polystyrene standard samples, 5.8 × 100, 1.085 × 10000, 5.95 × 10000, 3.2 × 100,000, 2.56 × 1000000, 2.93 × 1000, 2.85 × 10000, Ten points of 1.48 × 100,000, 8.417 × 100,000, 7.5 × 1000000 were used.

(Glass transition temperature and endotherm)
As the measurement of the glass transition temperature, for example, using a differential scanning calorimeter (for example, DSC-6220R: Seiko Instruments Inc.), the glass transition temperature is first heated from room temperature to 150 ° C. at a heating rate of 10 ° C./min, and then at 150 ° C. Let stand for 10 minutes, let the sample cool to room temperature, let stand for 10 minutes, then heat again to 150 ° C. at a heating rate of 10 ° C./min. The baseline below the glass transition point and the height of the baseline above the glass transition point It can be obtained from a curve portion corresponding to 1/2.
Also, the endothermic amount and melting point of wax, crystalline resin, toner, etc. can be measured in the same manner. The endothermic amount is obtained by calculating the peak area of the measured endothermic peak. Generally, the wax used in the toner melts at a temperature lower than the fixing temperature of the toner, and the heat of fusion at that time appears as an endothermic peak. Some waxes have a heat of transition due to a phase transition in the solid phase in addition to the heat of fusion. In the present invention, the total is the endothermic amount of the heat of fusion. The temperature at the minimum value of the endothermic peak is defined as the melting point.
In the present invention, the melting point of the toner was determined by measuring before adding the external additive.

<Production of crystalline polyester resin C>
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introducing tube, 202 parts by mass (1.00 mol) of sebacic acid, 189 parts by mass of 1,6-hexanediol (1.60 mol), and dibutyltin oxide as a condensation catalyst 0.5 part by mass was added, and the reaction was carried out for 8 hours at 180 ° C. while distilling off the water produced under a nitrogen stream. Next, while gradually raising the temperature to 220 ° C., the reaction was carried out for 4 hours while distilling off the water and 1,6-hexanediol produced under a nitrogen stream, and the Mw was about 7 under a reduced pressure of 5 to 20 mmHg. The reaction was continued until the value reached 1,000, and [crystalline polyester resin C] was obtained. [Crystalline polyester resin C] obtained had Mw of 7,000.

<Production of amorphous polyester resin A>
In a reaction vessel equipped with a condenser, a stirrer and a nitrogen inlet tube, 230 parts of bisphenol A ethylene oxide 2-mole adduct, 530 parts of bisphenol A propion oxide 3-mole adduct, 190 parts terephthalic acid, 60 parts adipic acid and dibutyltin oxide 2 parts were added and reacted at 230 ° C. under normal pressure for 8 hours. Next, after reacting under reduced pressure of 10 to 15 mmHg for 5 hours, 44 parts of trimellitic anhydride was added to the reaction vessel, and reacted at 180 ° C. for 2 hours under normal pressure. ] Was synthesized. The obtained [Non-crystalline polyester resin A] had a number average molecular weight of 2,500, a weight average molecular weight of 7,000, a glass transition temperature of 50 ° C., and an acid value of 26 mgKOH / g.

<Production of isocyanate-modified polyester resin B>
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 682 parts of bisphenol A ethylene oxide 2-mole adduct, 81 parts of bisphenol A propylene oxide 2-mole adduct, 283 parts of terephthalic acid, 22 parts of trimellitic anhydride Then, 2 parts of dibutyltin oxide was charged and reacted at 230 ° C. under normal pressure for 8 hours. Next, it was reacted for 5 hours under a reduced pressure of 10 to 15 mmHg to synthesize [Intermediate Polyester 1]. The obtained [Intermediate polyester 1] has a number average molecular weight of 2,200, a weight average molecular weight of 9,700, a glass transition temperature of 54 ° C., an acid value of 0.5 mgKOH / g, and a hydroxyl value of 52 mgKOH / g. there were.
Next, 410 parts of [Intermediate polyester 1], 89 parts of isophorone diisocyanate, and 500 parts of ethyl acetate are placed in a reaction vessel equipped with a cooling pipe, a stirrer, and a nitrogen introduction pipe, and reacted at 100 ° C. for 5 hours. Modified polyester resin B] was obtained.

(Manufacture of master batch)
Carbon black (Cabot Legal 400R): 40 parts, Binder resin: Polyester resin (Sanyo Kasei RS-801, acid value 10, Mw 20,000, Tg 64 ° C.): 60 parts, water: 30 parts are mixed in a Henschel mixer. Thus, a mixture in which water was soaked into the pigment aggregate was obtained.
This was kneaded for 45 minutes with two rolls set at a roll surface temperature of 130 ° C., and pulverized to a size of 1 mm with a pulverizer to obtain a [masterbatch].

Example 1
<Oil phase preparation process>
545 parts of [Crystalline Polyester Resin C], 181 parts of [Paraffin Wax (melting point 74 ° C.)] and 1450 parts of ethyl acetate are charged in a container equipped with a stir bar and a thermometer. The temperature was kept at 5 ° C. for 5 hours and then cooled to 30 ° C. in 1 hour.
Next, 500 parts of [Masterbatch] and 100 parts of ethyl acetate were charged in a container and mixed for 1 hour to obtain [Raw material solution 1]. [Raw material solution 1] 1500 parts are transferred to a container, and using a bead mill (Ultra Visco Mill, manufactured by Imex Co., Ltd.), liquid feeding speed is 1 kg / hr, disk peripheral speed is 6 m / sec, and 0.5 mm zirconia beads are 80% by volume. The pigment and wax were dispersed under conditions of filling and 3 passes.
Next, 655 parts of a 66% ethyl acetate solution of [Amorphous Polyester Resin A] was added, followed by one pass with a bead mill under the above conditions to obtain [Pigment / WAX Dispersion 1]. [Pigment / WAX Dispersion 1] 976 parts were mixed with a TK homomixer (manufactured by Special Machine Engineering) at 5,000 rpm for 1 minute, and then 88 parts of [Isocyanate-modified polyester resin B] was added and a TK homomixer (specialized machine). To obtain [Oil Phase 1].
It was 52.0 mass% when solid content of the obtained [oil phase 1] was measured, and the quantity of ethyl acetate with respect to solid content was 92 mass%.

<Preparation of aqueous phase>
In a beaker, 200 parts of ion-exchanged water and 1.75% by weight of a 25% by weight aqueous dispersion of organic resin fine particles for dispersion stabilization (a copolymer of sodium salt of styrene-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate) were added. Parts, 0.40 part of sodium carboxymethylcellulose as a thickener, and 4.5 parts of a 48.5% aqueous solution of sodium dodecyl diphenyl ether disulfonate (manufactured by Sanyo Chemical Industries, "Eleminol MON-7") as a surfactant Dissolved uniformly. Thereafter, a diluted aqueous solution of sodium hydroxide, isophoronediamine (IPDA), tertiary amine (U-Cat660M) are added dropwise at a concentration ratio of 60:25:15, and then sodium hydroxide or acetic acid is added so that the pH becomes 8.3. Fine adjustment was performed to obtain [Aqueous Phase 1].

<Core particle production process>
Add 1200 parts of [Aqueous Phase 1] to the obtained [Oil Phase 1], and cool in a water bath to suppress the temperature rise due to shear heat of the mixer so that the temperature in the liquid is in the range of 20-30 ° C. , Adjusted at a rotation speed of 6,000 to 8,000 rpm using a TK homomixer and mixed for 2 minutes, and then adjusted at a rotation speed of 100 to 300 rpm with a three-one motor with an anchor blade attached for 20 minutes. The mixture was stirred and an emulsification process in which oil phase droplets serving as core particles were dispersed in an aqueous phase was performed to obtain [core particle slurry 1]. Thereafter, a convergence process was performed.

<Desolvent>
[Core slurry 1] was charged into a container equipped with a stirrer and a thermometer, and the solvent was removed at room temperature for 2 hours to obtain [Dispersion slurry 1].

<Washing → Drying>
[Dispersion Slurry 1] After 100 parts were filtered under reduced pressure, (1): 100 parts of ion-exchanged water was added to the filter cake, mixed with a TK homomixer (10 minutes at a rotation speed of 12,000 rpm), and then filtered.
(2): 100 parts of ion-exchanged water was added to the filter cake of (1), ultrasonic vibration was applied, and the mixture was mixed with a TK homomixer (30 minutes at 12,000 rpm) and then filtered under reduced pressure. This operation was repeated so that the electric conductivity of the reslurry liquid was 10 μS / cm or less.
(3): 10% hydrochloric acid was added so that the reslurry solution of (2) had a pH of 4, and the mixture was directly filtered with a three-one motor for 30 minutes.
(4): 100 parts of ion-exchanged water was added to the filter cake of (3), mixed with a TK homomixer (10 minutes at 12,000 rpm) and then filtered. This operation was repeated so that the reslurry liquid had an electric conductivity of 10 μS / cm or less to obtain [Filter Cake 1]. The remaining [Dispersion Slurry 1] was washed in the same manner and further mixed as [Filter Cake 1].
[Filtration cake 1] was dried at 45 ° C. for 48 hours in a circulating drier and sieved with a mesh of 75 μm to obtain [Toner base 1].

  100 parts of this toner base 1 is 1.05 part of silica fine powder RY50 [manufactured by Nippon Aerosil Co., Ltd .; average primary particle size 40 nm] as external additive A, and MSP009 [manufactured by Teika Co., Ltd.] which is silica as external additive B The average primary particle size 80 nm] and 0.5 part H20TM [manufactured by Clariant Japan, Inc .; average primary particle size 12 nm] 1.45 parts mixed with a Henschel mixer [external toner] 1] was obtained.

Examples 2-12 and Comparative Examples 1-2
Table 1 shows the ratio of surfactant, organic fine particles, thickener, isophoronediamine added to the aqueous phase, tertiary amine, sodium hydroxide aqueous solution, and the ratio of the three types of external additives A, B, and C. Except for the change to Example 1, toners 2 to 12 of Examples 2 to 12 and toners 13 to 14 of Comparative Examples 1 to 2 were produced in the same manner as Example 1.

  For the obtained toners 1 to 14, the circularity distribution of the toner, the adhesion force Fh (nN) to the flat surface, and the adhesion force Fr (mN) between the toner particles were measured by the method described above.

Developer development (carrier preparation)
Acrylic resin solution (solid content 50 wt%) 21.0 parts guanamine solution (solid content 70 wt%) 6.4 parts alumina particles [0.3 μm, specific resistance 10 ¹⁴ (Ω · cm)] 7.6 parts silicone resin solution 65 0.0 part [solid content: 23 wt% (SR2410: manufactured by Toray Dow Corning Silicone)]
Aminosilane 1.0 part [100 wt% solid content (SH6020: manufactured by Toray Dow Corning Silicone)]
Toluene 60.0 parts Butyl cellosolve 60.0 parts

The carrier raw material was dispersed with a homomixer for 10 minutes to obtain a coating film forming solution of an acrylic resin and a silicone resin containing alumina particles. Firing ferrite powder [(MgO) 1.8 (MnO) 49.5 (Fe ₂ O ₃ ) 48.0: average particle size; 25 μm] as the core material is coated with the above coating film forming solution on the surface of the core material. The coated ferrite powder was obtained by applying with a Spira coater (Okada Seiko Co., Ltd.) to a thickness of 15 μm and drying. The obtained coated ferrite powder was fired in an electric furnace at 150 ° C. for 1 hour. After cooling, the ferrite powder bulk was crushed using a sieve having an aperture of 106 μm to obtain a carrier. The measurement of the binder resin film thickness was performed by observing the cross section of the carrier with a transmission electron microscope so that the coating film covering the carrier surface could be observed. Thus, a carrier a having a weight average particle diameter of 35 μm was obtained.

(Preparation of two-component developer)
Two-component developer using toner 1-14 and carrier a described above, and uniformly mixing and charging 5 parts by mass of toner with respect to 100 parts by mass of carrier using a type of tumbler mixer in which the container rolls and stirs. 1-14 were produced.

[Evaluation of toner]
Each of the two-component developers 1 to 14 was evaluated using a digital full color copying machine (image MP MP6000 manufactured by Ricoh).

(Transfer stability)
After the image area ratio 20% chart is transferred from the photoconductor to the paper, the transfer residual toner on the photoconductor immediately before the cleaning is transferred to a white paper with a scotch tape (manufactured by Sumitomo 3M Co., Ltd.), and is transferred to a Macbeth reflection densitometer RD514 type. Measured and evaluated according to the following criteria.
〔Evaluation criteria〕
A: The difference from the blank is less than 0.005.
(Circle): The difference with a blank is 0.005-0.010.
(Triangle | delta): The difference with a blank is 0.011-0.020.
X: The difference with a blank exceeds 0.02.

(Cleanability)
When 5000 sheets were continuously printed on a 5% chart using Ricoh's Ipsio C220, the toner adhesion of the photoreceptor after cleaning was observed with a CCD microscope camera (Keyence Corporation Hyper Macroscope) and evaluated according to the following criteria.
〔Evaluation criteria〕
(Double-circle): The cleaning defect in which a toner slips through a blade did not occur at all.
○: Although toner slightly slipped through the blade during cleaning, there was no practical problem.
Δ: Some toner slips through the blade during cleaning, but there was no practical problem.
X: A cleaning failure occurred in which the toner slips through the blade during cleaning, and there was a problem in practical use.

(Chargeability)
In a room temperature and humidity room (temperature: 23.5 ° C., humidity: 50% RH), the humidity is adjusted for 30 minutes or longer in an open system, 2 g of initial carrier and 0.14 g of toner are added to a stainless steel container, and then sealed. Run for 1 minute at 150 rpm on a YS-LD (Yayoi Co., Ltd. shaker), and charge 1 g of the sample on the electric sleeve with a charge flight type charge measuring device [DIT Corporation]. After applying a dash and applying a bias of -2.0 Kv for 60 seconds, the charge amount was measured from the total charge at that time and the amount of toner flying from the sample.
〔Evaluation criteria〕
Hereinafter, the unit is (−μc / g).
◎: More than 30 and less than 35 ○: More than 25 and less than or equal to 30 or less than 35 and less than 40 Δ: More than 20 and less than or equal to 25 or less than 40 and less than 45 x: Outside the above range

(Manufacturability during emulsification)
The result of granulation was evaluated by the number of particles (the number of small particles) of the ultrafine powder component measured by a flow type particle image analyzer FPIA-3000S. If the number of ultrafine particles is too large, the close-up of the fine powder is remarkably deteriorated in the convergence process in the next process, and the particle size distribution becomes broad. The sample collection timing was determined as follows for the sample immediately after the emulsification step and immediately before the convergence step was started.
〔Evaluation criteria〕
A: The number of small particles was less than 3%.
○: The number of small particles was 3% or more and less than 5%.
Δ: The number of small particles was 5% or more and less than 10%.
X: The number of small particles of 10% or more was observed.

  Table 2 summarizes the physical properties of the toners obtained in Examples 1-12 and Comparative Examples 1-2.

  From the results of Tables 1 and 2, the particles having a circularity of 0.963 or more and 0.984 or less account for 45.0-50.0% of the total toner in the circularity distribution of the toner. It can be seen that all of the stability, cleaning property, charging property and emulsification productivity were good values.

10 Electrostatic latent image carrier (photosensitive drum)
10K Black electrostatic latent image carrier 10Y Yellow electrostatic latent image carrier 10M Magenta electrostatic latent image carrier 10C Cyan electrostatic latent image carrier 14 Roller 15 Roller 16 Roller 17 Cleaning device 18 Image forming means 20 Charging roller 21 Exposure device 22 Secondary transfer device 23 Roller 24 Secondary transfer belt 25 Fixing device 26 Fixing belt 27 Pressure roller 28 Sheet reversing device 32 Contact glass 33 First traveling body 34 Second traveling body 35 Imaging lens 36 Reading Sensor 40 Developing device 41 Developing belt 42K Developer container 42Y Developer container 42M Developer container 42C Developer container 43K Developer supply roller 43Y Developer supply roller 43M Developer supply roller 43C Developer supply roller 44K Developer roller 44Y Developing roller 44M Developing roller 44C Developing roller 45K Black development unit 45Y Yellow development unit 45M Magenta development unit 45C Cyan development unit 49 Registration roller 50 Intermediate transfer belt 51 Roller 52 Separation roller 53 Manual feed path 54 Manual feed tray 55 Switching claw 56 Discharge roller 57 Discharge tray 58 Corona charging device 60 Cleaning device 61 Developing device 62 Transfer roller 63 Photoconductor cleaning device 64 Static elimination lamp 70 Static elimination lamp 80 Transfer roller 90 Cleaning device 95 Transfer paper 100A, 100B, 100C Image forming device 101 Electrostatic latent image carrier 102 Charging device 103 From exposure device Exposure device 104 developing device 105 recording paper 107 cleaning unit 108 transfer roller 120 image forming unit 130 document table 142 paper feed roller 143 paper bank 144 paper feed cassette 45 the separation roller 146 feed path 147 transport rollers 148 feed path 150 copier main body 160 a charging roller 200 feeder table 300 Scanner 400 automatic document feeder (ADF)

JP 2008-225386 A

Claims (11)

An electrostatic latent image developing toner comprising at least a binder resin, a wax, a colorant and organic fine particles,
A toner for developing an electrostatic latent image, wherein particles having a circularity of 0.963 to 0.984 occupy 45.0 to 50.0% of the total toner in the circularity distribution of the toner.   2. The electrostatic latent image development according to claim 1, wherein particles having a circularity of 0.963 to 0.984 occupy 46.0 to 49.0% of the total toner in the circularity distribution of the toner. Toner.   2. The electrostatic latent image development according to claim 1, wherein particles having a circularity of 0.963 to 0.984 occupy 47.0 to 48.0% of the total toner in the circularity distribution of the toner. Toner. 2. The electrostatic latent image development according to claim 1, wherein the toner has an adhesion force Fh (nN) with respect to a plane satisfying the following expression 1 and an adhesion force Fr (mN) between toner particles satisfying the following expression 2. Toner.
3 ≦ Fh ≦ 15 (Formula 1)
50 ≦ Fr ≦ 100 (Formula 2) 2. The electrostatic latent image development according to claim 1, wherein the toner has an adhesion force Fh (nN) with respect to a flat surface satisfying the following expression 3 and an adhesion force Fr (mN) between toner particles satisfying the following expression 4: Toner.
6 <Fh <12 (Formula 3)
60 <Fr <90 (Formula 4) 2. The electrostatic latent image development according to claim 1, wherein the toner has an adhesion force Fh (nN) with respect to a plane satisfying the following expression 5 and an adhesion force between toner particles Fr (mN) satisfying the following expression 6. Toner.
8 <Fh <10 (Formula 5)
70 <Fr <80 (Formula 6)   The electrostatic latent image developing toner according to claim 1, wherein the binder resin contains a crystalline resin and an amorphous resin.   A developer comprising: a carrier; and the electrostatic latent image developing toner according to claim 1.   A toner accommodating unit that accommodates the toner for developing an electrostatic latent image according to claim 1. An electrostatic latent image carrier;
An electrostatic latent image forming means for forming an electrostatic latent image on the electrostatic latent image carrier;
Developing means for developing the electrostatic latent image with a developer to form a visible image;
Transfer means for transferring the visible image onto a recording medium;
Fixing means for fixing the transferred image transferred onto the recording medium;
Cleaning means for removing toner remaining on the electrostatic latent image carrier;
Have
An image forming apparatus, wherein the developer includes the electrostatic latent image developing toner according to claim 1. An electrostatic latent image forming step of forming an electrostatic latent image on the electrostatic latent image carrier;
A developing step of developing the electrostatic latent image with a developer to form a visible image;
A transfer step of transferring the visible image onto a recording medium;
A fixing step of fixing the transferred image transferred onto the recording medium;
A cleaning step of removing toner remaining on the electrostatic latent image carrier;
Have
An image forming method, wherein the developer comprises the electrostatic latent image developing toner according to claim 1.