JP2015184475A - Toner for electrostatic charge image development, electrostatic charge image developer, toner cartridge, process cartridge, image forming apparatus, and image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a toner for electrostatic charge image development that suppresses the occurrence of toner contamination inside an image forming apparatus.SOLUTION: There is provided a toner for electrostatic charge image development that includes toner particles having the surface modified with polyalkylene imine, fatty acid metal salt particles having a volume average particle diameter of 8 μm or more and 20 μm or less, and inorganic particles having the surface treated with silicone oil and having an amount of free oil of 0.1 mass% or more and 1.5 mass% or less.

Description

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

Various toners used in electrophotographic image forming apparatuses are known.
For example, Patent Document 1 discloses a black toner obtained by surface-modifying toner base particles containing carbon black and a binder resin with polyalkyleneimine.
For example, Patent Document 2 contains toner particles containing a crystalline resin and a colorant, and silica particles having an average primary particle size treated with silicone oil of 50 nm to 150 nm, and the amount of free oil in the silica particles is An electrostatic charge image developing toner having a content of 0.1% by mass to 3% by mass is disclosed.
For example, Patent Document 3 includes toner particles containing a crystalline resin and an external additive, the external additive includes silicon oxide particles surface-treated with oil, and the free oil amount of the silicon oxide particles is less than 3%. An electrostatic charge image developing toner is disclosed.

Japanese Patent No. 5115379 JP 2009-98194 A JP 2009-25744 A

  An object of the present invention is to provide a toner for developing an electrostatic charge image that suppresses the occurrence of toner contamination inside an image forming apparatus.

The above problem is solved by the following means. That is,
The invention according to claim 1
Toner particles surface-modified with polyalkyleneimine;
Fatty acid metal salt particles having a volume average particle diameter of 8 μm or more and 20 μm or less;
Inorganic particles surface-treated with silicone oil and having a free oil amount of 0.1% by mass or more and 1.5% by mass or less;
A toner for developing an electrostatic charge image.

The invention according to claim 2
The toner for developing an electrostatic charge image according to claim 1, wherein the number average particle diameter of the inorganic particles is 20 nm or more and 60 nm or less.

The invention according to claim 3
The electrostatic image developing toner according to claim 1, wherein the inorganic particles are silica particles.

The invention according to claim 4
The electrostatic image developing toner according to claim 1, wherein the polyalkyleneimine is polyethyleneimine.

The invention according to claim 5
The toner for developing an electrostatic charge image according to any one of claims 1 to 4, which is a non-magnetic one-component toner.

The invention according to claim 6
An electrostatic charge image developer comprising the electrostatic charge image developing toner according to claim 1.

The invention according to claim 7 provides:
The electrostatic charge image developer according to claim 6, which is a non-magnetic one-component developer.

The invention according to claim 8 provides:
Containing the toner for developing an electrostatic charge image according to any one of claims 1 to 5,
A toner cartridge to be attached to and detached from the image forming apparatus.

The invention according to claim 9 is:
A developing means for containing the electrostatic charge image developer according to claim 6 or 7 and developing the electrostatic charge image formed on the surface of the image carrier as a toner image by the electrostatic charge image developer,
A process cartridge attached to and detached from the image forming apparatus.

The invention according to claim 10 is:
An image carrier,
Charging means for charging the surface of the image carrier;
An electrostatic charge image forming means for forming an electrostatic charge image on the surface of the charged image carrier;
Development means for containing the electrostatic charge image developer according to claim 6 or 7 and developing the electrostatic charge image formed on the surface of the image carrier as a toner image by the electrostatic charge image developer;
Transfer means for transferring a toner image formed on the surface of the image carrier to the surface of a recording medium;
Fixing means for fixing the toner image transferred to the surface of the recording medium;
An image forming apparatus comprising:

The invention according to claim 11 is:
A charging step for charging the surface of the image carrier;
An electrostatic charge image forming step of forming an electrostatic charge image on the surface of the charged image carrier;
A developing step of developing an electrostatic charge image formed on the surface of the image carrier as a toner image by the electrostatic charge image developer according to claim 6 or 7,
A transfer step of transferring a toner image formed on the surface of the image carrier to the surface of a recording medium;
A fixing step of fixing the toner image transferred to the surface of the recording medium;
An image forming method comprising:

According to the first aspect of the present invention, the electrostatic charge image development that suppresses the occurrence of toner contamination inside the image forming apparatus compared to the case where the toner does not satisfy the requirement that the fatty acid metal salt particles and the inorganic particles are included. Toner is provided.
According to the second aspect of the present invention, there is provided an electrostatic charge image developing toner that further suppresses the occurrence of toner contamination inside the image forming apparatus as compared with the case where the number average particle diameter of the inorganic particles is outside the range. The

According to the invention of claim 3, in the toner to which silica particles are applied as the inorganic particles, the inside of the image forming apparatus is compared with a case where the toner does not satisfy the requirement that the toner contains the fatty acid metal salt particles and the inorganic particles. An electrostatic charge image developing toner that suppresses the occurrence of toner contamination is provided.
According to the fourth aspect of the present invention, in the toner to which polyethyleneimine is applied as the polyalkyleneimine, the inner portion of the image forming apparatus does not satisfy the requirement that the toner contains the fatty acid metal salt particles and the inorganic particles. An electrostatic charge image developing toner that suppresses the occurrence of toner contamination is provided.
According to the fifth aspect of the present invention, there is provided an electrostatic charge image developing toner that suppresses the occurrence of toner contamination inside the image forming apparatus as compared with the non-magnetic two-component toner.

According to the sixth aspect of the present invention, compared with a case where the toner in the developer does not satisfy the requirement that the fatty acid metal salt particles and the inorganic particles are included, the occurrence of toner contamination inside the image forming apparatus is suppressed. An electrostatic charge image developer is provided.
According to the seventh aspect of the present invention, there is provided an electrostatic charge image developer that further suppresses the occurrence of toner contamination inside the image forming apparatus as compared with a non-magnetic two-component developer.

According to the eighth aspect of the present invention, there is provided a toner cartridge that suppresses the occurrence of toner contamination inside the image forming apparatus as compared with a case where the toner does not satisfy the requirement that the fatty acid metal salt particles and the inorganic particles are included. Is done.
According to the ninth aspect of the present invention, compared to a case where the toner in the developer does not satisfy the requirement that the fatty acid metal salt particles and the inorganic particles are included, the occurrence of toner contamination inside the image forming apparatus is suppressed. A process cartridge is provided.

According to the tenth aspect of the present invention, compared to a case where the toner in the developer does not satisfy the requirement that the fatty acid metal salt particles and the inorganic particles are included, the occurrence of toner contamination inside the image forming apparatus is suppressed. An image forming apparatus is provided.
According to the eleventh aspect of the present invention, compared to a case where the toner in the developer does not satisfy the requirement that the fatty acid metal salt particles and the inorganic particles are included, the occurrence of toner contamination inside the image forming apparatus is suppressed. An image forming method is provided.

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

  Embodiments of the present invention will be described below. These descriptions and examples are illustrative of the invention and are not intended to limit the scope of the invention.

  In the present specification, (meth) acryl means acrylic or methacrylic, (meth) acrylic acid means acrylic acid or methacrylic acid, and (meth) acrylo means acrylo or methacrylo.

<Toner for electrostatic image development>
The toner for developing an electrostatic charge image (also referred to as “toner”) according to the exemplary embodiment includes fatty acid metal salt particles having a volume average particle diameter of 8 μm or more and 20 μm or less on toner particles surface-modified with polyalkyleneimine. The toner is externally added with inorganic particles having a surface treatment with silicone oil and a free oil amount of 0.1% by mass to 1.5% by mass. The toner according to the present embodiment is a positively charged toner because the toner particles are surface-modified with polyalkyleneimine.

  In the toner according to the exemplary embodiment, the fatty acid metal salt particles and the inorganic particles are externally added to the toner particles surface-modified with polyalkyleneimine, so that the inside of the image forming apparatus is hardly contaminated. The presumed mechanism is explained below. Hereinafter, the inorganic particles surface-treated with silicone oil are also referred to as “oil-treated inorganic particles”.

  Conventionally, as a means for imparting positive charge to toner used as a non-magnetic one-component developer, it is known that the surface of toner particles is modified with polyalkyleneimine. This surface modification is performed, for example, by reacting the acid group of the resin on the toner particle surface with the amino group of the polyalkyleneimine and covalently bonding the polyalkyleneimine to the resin. Thus, although the polyalkyleneimine adheres to the surface of the toner particles, when a mechanical load (for example, repeated stirring in the developing device) is applied to the toner particles, the polyalkyleneimine chain is released and the polyalkyleneimine on the surface of the toner particles is removed. The amount of alkyleneimine is decreased, and as a result, the charge of the toner may be lowered. When the charge of the toner is lowered, the toner is likely to be scattered during image formation, and toner contamination inside the image forming apparatus occurs. In particular, in a high-temperature and high-humidity environment (for example, 30 ° C. or higher and 80% RH or higher), the polyalkyleneimine is likely to be detached from the toner particle surface, and the toner is likely to adhere to the member surface of the image forming apparatus. In combination with this, toner contamination inside the image forming apparatus tends to occur.

With respect to the above phenomenon, the toner according to the exemplary embodiment includes fatty acid metal salt particles and oil-treated inorganic particles as external additives, thereby suppressing toner contamination inside the image forming apparatus.
The fatty acid metal salt particles have a property of easily adsorbing polyalkyleneimine and a property of easily adsorbing silicone oil. Due to both of these properties, it is considered that the fatty acid metal salt particles capture the polyalkyleneimine released from the toner particles, while releasing the polyalkyleneimine by interaction with the silicone oil. As a result, even though the polyalkyleneimine is detached from the toner particle surface with use, it is returned to the toner particle surface by the capture and release by the fatty acid metal salt particles, thus suppressing the occurrence of charge reduction of the toner particles. It is considered that toner scattering is suppressed.
Here, in order for the fatty acid metal salt particles to efficiently capture the polyalkyleneimine, it is necessary for the fatty acid metal salt particles to be present free from the toner particles. It is estimated that 8 μm or more and 20 μm or less is appropriate. If the particle size is less than 8 μm, the fatty acid metal salt particles are difficult to be separated from the toner particles, and if the particle size is more than 20 μm, the fatty acid metal salt particles are likely to aggregate, and in either case, the efficiency of capturing the polyalkyleneimine decreases. Conceivable. Furthermore, since the fatty acid metal salt particles tend to aggregate when the particle diameter exceeds 20 μm, the aggregated fatty acid metal salt particles may cause contamination inside the image forming apparatus or image contamination.
In addition, in order for the fatty acid metal salt particles to efficiently capture and release the polyalkyleneimine, there is an appropriate amount of silicone oil that can interact with the fatty acid metal salt particles around the fatty acid metal salt particles. Therefore, it is estimated that the amount of free oil in the oil-treated inorganic particles is suitably from 0.1% by mass to 1.5% by mass. If the amount of free oil in the oil-treated inorganic particles is less than 0.1% by mass, the fatty acid metal salt particles are unlikely to be released from the toner particles, and the polyalkyleneimine is unlikely to be released from the fatty acid metal salt particles. On the other hand, when the amount of free oil in the oil-treated inorganic particles exceeds 1.5% by mass, it is considered that the fatty acid metal salt particles hardly capture the polyalkyleneimine.

  For the reasons described above, in the present embodiment, the fatty acid metal salt particles have a volume average particle size of 8 μm to 20 μm, and a more desirable volume average particle size of 10 μm to 15 μm. The amount of free oil in the inorganic particles is 0.1% by mass or more and 1.5% by mass or less, and more preferably 0.5% by mass or more and 1.2% by mass or less.

  The toner according to the exemplary embodiment does not need to be a magnetic toner and does not need to be a two-component toner because the toner particles are surface-modified with polyalkyleneimine to be positively charged. Therefore, it is desirable to use a non-magnetic one-component toner. The toner according to the exemplary embodiment is also a two-component toner because the polyalkyleneimine is likely to be detached from the surface of the toner particles when the developing device is stirred together with the carrier, and the charge of the toner is likely to be lowered. It is preferable to use a one-component toner rather than a toner.

  Hereinafter, the configuration of the toner according to the exemplary embodiment will be described in detail.

[Toner particles]
The toner according to the exemplary embodiment includes toner particles surface-modified with polyalkyleneimine. The toner particles include, for example, a binder resin and a colorant, and may further include a release agent and other internal additives.

-Polyalkyleneimine-
The surface of the toner particles is modified with polyalkyleneimine. The surface modification by polyalkyleneimine means that the polyalkyleneimine is attached to the surface of the toner particles. For example, the surface modification is performed by binding at least part of the amino group of the polyalkyleneimine. It is carried out by chemical bond (covalent bond, ionic bond) with acidic group derived from resin; bond by intermolecular force between molecule on toner particle surface and polyalkyleneimine.

  A polyalkyleneimine is a highly positively charged compound having a large number of amino groups. The toner particles surface-modified with polyalkyleneimine have a positive charge.

Examples of the polyalkyleneimine include polyethyleneimine, polypropyleneimine, polybutyleneimine, polyisopropyleneimine and the like. The alkyleneimine includes polyalkyleneimine derivatives into which a substituent such as an alkyl group has been introduced.
Among these, polyethyleneimine is desirable from the viewpoint of good reactivity with the binder resin and the amount of positive charge per unit mass.

  The number average molecular weight of the polyalkyleneimine is preferably from 5,000 to 100,000, and more preferably from 10,000 to 80,000. When the number average molecular weight of the polyalkyleneimine is within the above range, the surface of the toner particles can be more effectively modified, and aggregation of the toner particles is suppressed by steric hindrance due to the relatively long molecular chain of the polyalkyleneimine. obtain.

-Binder resin-
Examples of the binder resin include styrenes (for example, styrene, parachlorostyrene, α-methylstyrene, etc.), (meth) acrylic acid esters (for example, methyl (meth) acrylate, ethyl (meth) acrylate, (meth ) N-propyl acrylate, n-butyl (meth) acrylate, lauryl (meth) acrylate, 2-ethylhexyl (meth) acrylate), ethylenically unsaturated nitriles (eg (meth) acrylonitrile), vinyl ether Homopolymers (eg, vinyl methyl ether, vinyl isobutyl ether, etc.), vinyl ketones (eg, vinyl methyl ketone, vinyl ethyl ketone, vinyl isopropenyl ketone, etc.), olefins (eg, ethylene, propylene, butadiene, etc.) A polymer is mentioned.
Typical binder resins include, for example, polyester resins, epoxy resins, polyurethane resins, polyamide resins, cellulose resins, polyether resins, polystyrene, styrene- (meth) acrylic acid alkyl copolymers, styrene- (meth) acrylonitrile. Examples thereof include a copolymer, a styrene-butadiene copolymer, and a styrene-maleic anhydride copolymer.
These resins may be used alone or in combination of two or more.

  The content of the binder resin in the toner particles is preferably from 40% by weight to 95% by weight, more preferably from 50% by weight to 90% by weight, and even more preferably from 60% by weight to 85% by weight.

  A polyester resin is suitable as the binder resin. As a polyester resin, the condensation polymer of polyhydric carboxylic acid and polyhydric alcohol is mentioned, for example. As the polyester resin, a commercially available product may be used, or a synthesized resin may be used.

Examples of the polyvalent carboxylic acid include aliphatic dicarboxylic acids (eg, oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, alkenyl succinic acid, adipic acid, sebacic acid, etc.) Alicyclic dicarboxylic acids (for example, cyclohexanedicarboxylic acid), aromatic dicarboxylic acids (for example, terephthalic acid, isophthalic acid, phthalic acid, naphthalenedicarboxylic acid, etc.), their anhydrides, or lower (for example, having 1 or more carbon atoms) 5 or less) alkyl esters. Among these, as polyvalent carboxylic acid, aromatic dicarboxylic acid is preferable, for example.
The polyvalent carboxylic acid may be used in combination with a dicarboxylic acid or a trivalent or higher carboxylic acid having a crosslinked structure or a branched structure. Examples of the trivalent or higher carboxylic acid include trimellitic acid, pyromellitic acid, anhydrides thereof, or lower (eg, having 1 to 5 carbon atoms) alkyl ester.
A polyvalent carboxylic acid may be used individually by 1 type, and may use 2 or more types together.

Examples of the polyhydric alcohol include aliphatic diols (for example, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentyl glycol, etc.), alicyclic diols (for example, cyclohexanediol, cyclohexanedimethanol, Hydrogenated bisphenol A, etc.) and aromatic diols (for example, ethylene oxide adducts of bisphenol A, propylene oxide adducts of bisphenol A, etc.). Among these, as the polyhydric alcohol, for example, aromatic diols and alicyclic diols are preferable, and aromatic diols are more preferable.
The polyhydric alcohol may be used in combination with a diol and a trivalent or higher alcohol having a crosslinked structure or a branched structure. Examples of the trivalent or higher alcohol include glycerin, trimethylolpropane, pentaerythritol and the like.
A polyhydric alcohol may be used individually by 1 type, and may use 2 or more types together.

The glass transition temperature (Tg) of the polyester resin is preferably 50 ° C. or higher and 80 ° C. or lower, and more preferably 50 ° C. or higher and 65 ° C. or lower.
The glass transition temperature is determined from a DSC curve obtained by differential scanning calorimetry (DSC). More specifically, it is determined by “extrapolated glass transition start temperature” described in JIS K7121-1987 “Method for Measuring Glass Transition Temperature”.

The weight average molecular weight (Mw) of the polyester resin is preferably from 5,000 to 1,000,000, and more preferably from 7,000 to 500,000.
The number average molecular weight (Mn) of the polyester resin is preferably 2,000 or more and 100,000 or less.
The molecular weight distribution Mw / Mn of the polyester resin is preferably 1.5 or more and 100 or less, and more preferably 2 or more and 60 or less.
The weight average molecular weight and number average molecular weight of the resin are measured by gel permeation chromatography (GPC). The molecular weight measurement by GPC is performed using HLC-8120 manufactured by Tosoh Corporation as a measuring device, TSKgel SuperHM-M15 cm manufactured by Tosoh Corporation as a column, and tetrahydrofuran as a solvent. The weight average molecular weight and the number average molecular weight are calculated using a molecular weight calibration curve prepared from a monodisperse polystyrene standard sample from this measurement result.

-Colorant-
Examples of the colorant include carbon black, chrome yellow, hansa yellow, benzidine yellow, sren yellow, quinoline yellow, pigment yellow, permanent orange GTR, pyrazolone orange, vulcan orange, watch young red, permanent red, brilliantamine 3B, brilliant. Carmine 6B, Dupont Oil Red, Pyrazolone Red, Resol Red, Rhodamine B Lake, Lake Red C, Pigment Red, Rose Bengal, Aniline Blue, Ultramarine Blue, Calco Oil Blue, Methylene Blue Chloride, Phthalocyanine Blue, Pigment Blue, Phthalocyanine Green, Pigments such as malachite green oxalate; acridine, xanthene, azo, benzoquinone , Azine, anthraquinone, thioindigo, dioxazine, thiazine, azomethine, indigo dyes, phthalocyanine, aniline black, polymethine, triphenylmethane dyes, diphenylmethane dyes, dye thiazole like; and the like. A colorant may be used individually by 1 type and may use 2 or more types together.

  As the colorant, a surface-treated colorant may be used as necessary, or it may be used in combination with a dispersant.

  The content of the colorant is desirably 1% by mass or more and 30% by mass or less of the toner particles, and more desirably 3% by mass or more and 15% by mass or less.

-Release agent-
Examples of release agents include hydrocarbon waxes; natural waxes such as carnauba wax, rice wax, and candelilla wax; synthetic or mineral / petroleum waxes such as montan wax; and ester waxes such as fatty acid esters and montanic acid esters. And so on. The release agent is not limited to this.

The melting temperature of the release agent is preferably 50 ° C. or higher and 110 ° C. or lower, and more preferably 60 ° C. or higher and 100 ° C. or lower.
The melting temperature of the release agent is determined by the “melting peak temperature” described in the method for determining the melting temperature in JIS K7121-1987 “Method for measuring the transition temperature of plastic” from the DSC curve obtained by differential scanning calorimetry (DSC). Ask.

  The content of the release agent in the toner particles is preferably 1% by mass to 20% by mass, and more preferably 5% by mass to 15% by mass.

-Other additives-
Examples of other additives include known additives such as a magnetic material, a charge control agent, and inorganic powder. These additives are contained in the toner particles as internal additives.

-Toner particle characteristics-
The toner particles may be toner particles having a single layer structure, or toner particles having a so-called core / shell structure composed of a core (core particle) and a coating layer (shell layer) covering the core. May be.

  The volume average particle diameter (D50v) of the toner particles is preferably 2 μm or more and 15 μm or less, more preferably 3 μm or more and 10 μm or less, and further preferably 4 μm or more and 8 μm or less.

Various average particle diameters and various particle size distribution indexes of the toner particles are measured using Coulter Multisizer II (manufactured by Beckman-Coulter), and the electrolyte is measured using ISOTON-II (manufactured by Beckman-Coulter).
In the measurement, 0.5 mg to 50 mg of a measurement sample is added as a dispersant to 2 ml of a 5% aqueous solution of a surfactant (preferably sodium alkylbenzenesulfonate). This is added to 100 ml or more and 150 ml or less of the electrolytic solution.
The electrolyte in which the sample is suspended is dispersed for 1 minute with an ultrasonic disperser, and the particle size distribution of particles having a particle size in the range of 2 μm to 60 μm is obtained using a 100 μm aperture with a Coulter Multisizer II. taking measurement. The number of particles to be sampled is 50,000.
A cumulative distribution is drawn from the smaller diameter side to the particle size range (channel) divided based on the measured particle size distribution, and the cumulative particle size of 16% is the volume particle size D16v. D16p, the particle size that is 50% cumulative is defined as the volume average particle size D50v, the number average particle size D50p, and the particle size that is cumulative 84% is defined as the volume particle size D84v and the number particle size D84p.
Using these, the volume average particle size distribution index (GSDv) is calculated as (D84v / D16v) ^1/2 and the number average particle size distribution index (GSDp) is calculated as (D84p / D16p) ^1/2 .

  The shape factor SF1 of the toner particles is preferably 110 or more and 150 or less, and more preferably 120 or more and 140 or less.

The shape factor SF1 is obtained by the following equation.
Formula: SF1 = (ML ² / A) × (π / 4) × 100
In the above formula, ML represents the absolute maximum length of the toner, and A represents the projected area of the toner.
Specifically, the shape factor SF1 is quantified mainly by analyzing a microscope image or a scanning electron microscope image using an image analyzer, and is calculated as follows. That is, by capturing an optical microscope image of particles dispersed on the surface of a slide glass into a Luzex image analyzer using a video camera, obtaining the maximum length and projected area of 100 particles, calculating by the above formula, and obtaining the average value can get.

(External additive)
The toner according to the exemplary embodiment has a surface treatment with a fatty acid metal salt particle having a volume average particle diameter of 8 μm or more and 20 μm or less as an external additive, and a free oil amount of 0.1% by mass to 1.5% by mass with silicone oil. And the following inorganic particles, and may further contain other external additives.

-Fatty acid metal salt particles-
Fatty acid metal salt particles are particles of a salt of a fatty acid and a metal.
The fatty acid may be either a saturated fatty acid or an unsaturated fatty acid, preferably a fatty acid having 10 to 25 carbon atoms (desirably 15 to 25 carbon atoms). Examples of the saturated fatty acid include lauric acid, stearic acid, and behenic acid, and stearic acid is preferable. Examples of the unsaturated fatty acid include oleic acid and linoleic acid.
As said metal, a bivalent metal is preferable, For example, magnesium, calcium, aluminum, barium, and zinc are mentioned, Magnesium, calcium, and zinc are preferable.

  Examples of the fatty acid metal salt particles include aluminum stearate, calcium stearate, potassium stearate, magnesium stearate, barium stearate, lithium stearate, zinc stearate, copper stearate, lead stearate, nickel stearate, stearic acid. Strontium, cobalt stearate, sodium stearate; zinc oleate, manganese oleate, iron oleate, aluminum oleate, copper oleate, magnesium oleate, calcium oleate; zinc palmitate, cobalt palmitate, copper palmitate, Magnesium palmitate, aluminum palmitate, calcium palmitate; zinc laurate, manganese laurate, calcium laurate, iron laurate, lauric Magnesium acid, aluminum laurate; zinc linoleate, cobalt linoleate, calcium linoleate, zinc ricinoleate, aluminum ricinoleate; and the respective particles such as.

  The fatty acid metal salt particles are preferably fatty acid metal salt particles having a melting temperature of 40 ° C. or higher and 200 ° C. or lower from the viewpoint of fluidity, fixing properties, etc., and each particle of zinc stearate, zinc laurate, and magnesium stearate Are preferred, and zinc stearate particles are more preferred.

Examples of the method for producing a fatty acid metal salt include a method in which a fatty acid alkali metal salt is cationically substituted; a method in which a fatty acid is reacted with a metal hydroxide. Examples of the method for producing zinc stearate include a method in which sodium stearate is replaced with a cation; a method in which stearic acid is reacted with zinc hydroxide.
The fatty acid metal salt particles can be produced, for example, by pulverizing solids of fatty acid metal salts.

  In the present embodiment, the volume average particle size of the fatty acid metal salt particles is 8 μm or more and 20 μm or less, and more preferably 10 μm or more and 15 μm or less.

In this embodiment, the volume average particle diameter of the fatty acid metal salt particles can be measured, for example, by the following method.
1 g of toner is placed in a 1 L beaker and 500 g of a 5% aqueous solution of a surfactant (preferably sodium alkylbenzene sulfonate) is added. After applying an ultrasonic wave to release the external additive from the toner particles, the centrifugal separation is performed. Since the density of the fatty acid metal salt particles is less than 1 and the toner is usually 1 or more, the supernatant after centrifugation contains the fatty acid metal salt particles. 2 ml of this supernatant is added to 100 ml to 150 ml of an electrolytic solution (ISOTON-II manufactured by Beckman-Coulter), and subjected to a dispersion treatment with an ultrasonic disperser for 1 minute to obtain a measurement sample. Using Coulter Multisizer type II (manufactured by Beckman-Coulter Inc., aperture diameter 100 μm), the particle size of 50,000 particles of 2 μm or more and 60 μm or less is measured, and the cumulative distribution of the volume is drawn from the small diameter side. % Is defined as the volume average particle diameter (D50v).

  In this embodiment, the external addition amount of the fatty acid metal salt particles is preferably 0.3% by mass or more and 5% by mass or less, more preferably 0.5% by mass or more and 3% by mass or less, based on the mass of the toner particles. More preferably, it is more than 2% by mass.

-Oil-treated inorganic particles-
As inorganic particles, silica (SiO ₂ ), titania (TiO ₂ ), alumina (Al ₂ O ₃ ), CuO, ZnO, SnO ₂ , CeO ₂ , Fe ₂ O ₃ , MgO, BaO, CaO, K ₂ O, Examples thereof include particles such as Na ₂ O, ZrO ₂ , CaO · SiO ₂ , K ₂ O · (TiO ₂ ) n, Al ₂ O ₃ · 2SiO ₂ , CaCO ₃ , MgCO ₃ , BaSO ₄ , and MgSO ₄ .

  As a surface treatment method of inorganic particles using silicone oil, a dry method using a spray dry method in which a solution containing silicone oil is sprayed on inorganic particles floating in the gas phase; And a wet method in which inorganic particles are immersed and dried. Further, after the above treatment, the excessive silicone oil may be removed by immersing inorganic particles in an organic solvent such as ethanol.

  Silicone oils include dimethyl silicone oil, alkyl-modified silicone oil, amino-modified silicone oil, carboxyl-modified silicone oil, epoxy-modified silicone oil, fluorine-modified silicone oil, alcohol-modified silicone oil, polyether-modified silicone oil, methylphenyl silicone oil, Examples thereof include methyl hydrogen silicone oil, mercapto modified silicone oil, higher fatty acid modified silicone oil, phenol modified silicone oil, methacrylic acid modified silicone oil, polyether modified silicone oil, methyl styryl modified silicone oil and the like.

  As the oil-treated inorganic particles, oil-treated silica particles are desirable. The oil-treated silica particles are preferably produced by a sol-gel method. In a specific production method, first, tetraalkoxysilane is dropped into water containing alcohol together with ammonia water as a catalyst and stirred. Next, the silica sol suspension is centrifuged and separated into wet silica gel, alcohol and aqueous ammonia. A solvent is added to wet silica gel to form a silica sol again, and a hydrophobizing agent (silicone oil) is added to hydrophobize the silica surface. Next, the solvent is removed from the hydrophobized silica sol, dried and sieved to obtain oil-treated silica particles. The particle size of the silica particles can be controlled by the weight ratio of tetraalkoxysilane, ammonia, alcohol, water, reaction temperature, stirring rate, and supply rate.

  In the present embodiment, the amount of free oil in the inorganic particles is 0.1% by mass or more and 1.5% by mass or less, and more preferably 0.5% by mass or more and 1.2% by mass or less.

In the present embodiment, the amount of free oil in the inorganic particles can be measured, for example, by the following method.
2 g of toner is added to 40 ml of an aqueous solution of 0.2% surfactant (polyoxyethylene (10) octylphenyl ether having a polyoxyethylene polymerization degree of 10), and the toner is sufficiently dispersed so that the toner gets wet. In this state, using an ultrasonic homogenizer (US300T manufactured by Nippon Seiki Seisakusho), ultrasonic vibration with an output of 20 W and a frequency of 20 kHz is applied for 1 minute to release the external additive from the toner particles. Thereafter, the toner particles are precipitated and separated under conditions of 3000 rpm × 7 minutes through a 50 ml high-speed centrifuge with a precipitation tube (Model M160 IV manufactured by Sakuma Seisakusho), and the supernatant liquid is a membrane filter (Nippon Millipore Sequential filtration through FHLP02500, GSEP047S0), and the filtrate is dried. The above operation is repeated to obtain a dry sample.
The dried sample obtained above is subjected to a thermogravimetric analyzer (DTG-60 manufactured by Shimadzu Corporation), and the amount of mass reduction when heated to 600 ° C. is defined as the amount of free oil.

The oil-treated inorganic particles preferably have a number average particle size of 20 nm to 60 nm. When the number average particle diameter of the inorganic particles is within the above range, self-aggregation of the inorganic particles is suppressed, and oil supply from the inorganic particles to the fatty acid metal salt particles is efficiently performed. As a result, the fatty acid metal salt particles can be efficiently liberated from the toner particles, and the polyalkyleneimine can be stably supplied to the toner particles. Is more suppressed. The above-mentioned effect due to the number average particle diameter of the inorganic particles being in the above range is particularly remarkable under high temperature and high humidity.
In view of the above, the number average particle diameter of the inorganic particles is more preferably 25 nm or more and 55 nm or less, and further preferably 30 nm or more and 50 nm or less.

  The number average particle diameter of the inorganic particles is determined by observing 100 inorganic particles (primary particles) present on the surface of the toner particles with a scanning electron microscope (SEM), and analyzing the longest diameter and shortest diameter for each particle by image analysis. The diameter is measured, and an intermediate value between the two is defined as a sphere equivalent diameter, and the median diameter (cumulative 50% particle diameter) of the sphere equivalent diameter is defined as the number average particle diameter.

  In this embodiment, the external addition amount of the oil-treated inorganic particles is preferably 0.3% by mass or more and 5% by mass or less, more preferably 0.5% by mass or more and 3% by mass or less with respect to the mass of the toner particles. More preferably, it is more than 2% by mass.

-Other external additives-
Other external additives include inorganic particles not treated with oil (for example, particles of silica, titania, alumina, etc.), resin particles (resin particles of polystyrene, PMMA, melamine resin, etc.), cleaning activators (for example, fluorine And other high molecular weight particles).

  In this embodiment, the external additive amount of the other external additives is preferably 0.3% by mass or more and 5% by mass or less, and more preferably 0.5% by mass or more and 3% by mass or less with respect to the mass of the toner particles. Desirably, 1% by mass to 2% by mass is more desirable.

[Toner Production Method]
Hereinafter, toner particles before surface modification with polyalkyleneimine may be referred to as “toner mother particles”.

  The toner according to the exemplary embodiment is manufactured by producing toner particles and externally adding an external additive to the toner particles. The toner particles can be produced by producing toner mother particles and surface-modifying the toner mother particles with polyalkyleneimine.

The toner base particles may be produced by any of a dry production method (for example, a kneading pulverization method) and a wet production method (for example, an aggregation coalescence method, a suspension polymerization method, a dissolution suspension method, etc.). There is no restriction | limiting in particular in these manufacturing methods, A well-known manufacturing method is employ | adopted. Among these, it is preferable to obtain toner mother particles by an aggregation coalescence method.
When toner base particles produced by the aggregation and coalescence method are used, since the particle size distribution is narrow and the smoothness of the particle surface is high, there is little bias in the adhesion of the polyalkyleneimine to the toner base particle surface during toner production, In addition, even when used as a toner, the adhesion of polyalkyleneimine supplied from the fatty acid metal salt particles is less biased, and as a result, the occurrence of a decrease in charging of the toner particles is further suppressed, and the toner contamination in the image forming apparatus is reduced. Is more suppressed.

When the toner base particles are produced by the aggregation and coalescence method, specifically, for example,
A step of preparing a resin particle dispersion in which resin particles to be a binder resin are dispersed (resin particle dispersion preparation step); and a dispersion in which other particle dispersions are also mixed in the resin particle dispersion (if necessary) A process of aggregating resin particles (and other particles as necessary) to form aggregated particles (aggregated particle formation process); heating the aggregated particle dispersion in which the aggregated particles are dispersed, and aggregating The toner base particles are manufactured through a step of fusing and coalescing the particles to form toner particles (fusing and coalescence step).

  Details of each step will be described below. In the following description, a method for obtaining toner base particles containing a colorant and a release agent will be described. The colorant and the release agent are used as necessary. Of course, you may use other additives other than a coloring agent and a mold release agent.

-Preparation step of resin particle dispersion-
First, for example, a colorant dispersion in which colorant particles are dispersed and a release agent dispersion in which release agent particles are dispersed are prepared together with a resin particle dispersion in which resin particles to be a binder resin are dispersed.

  The resin particle dispersion is prepared, for example, by dispersing resin particles in a dispersion medium using a surfactant.

Examples of the dispersion medium used for the resin particle dispersion include an aqueous medium.
Examples of the aqueous medium include water such as distilled water and ion exchange water, and alcohols. These may be used individually by 1 type and may use 2 or more types together.

Examples of the surfactant include anionic surfactants such as sulfate ester, sulfonate, phosphate, and soap; cationic surfactants such as amine salt type and quaternary ammonium salt type; polyethylene glycol And nonionic surfactants such as polyphenols, alkylphenol ethylene oxide adducts, and polyhydric alcohols. Among these, an anionic surfactant and a cationic surfactant are particularly mentioned. The nonionic surfactant may be used in combination with an anionic surfactant or a cationic surfactant.
Surfactant may be used individually by 1 type and may use 2 or more types together.

Examples of the method for dispersing the resin particles in the dispersion medium in the resin particle dispersion include general dispersion methods such as a rotary shear type homogenizer, a ball mill having a medium, a sand mill, and a dyno mill. Depending on the type of resin particles, the resin particles may be dispersed in the resin particle dispersion using, for example, a phase inversion emulsification method.
In the phase inversion emulsification method, a resin to be dispersed is dissolved in a hydrophobic organic solvent in which the resin is soluble, a base is added to the organic continuous phase (O phase), and the aqueous medium (W In this method, the resin is converted from W / O to O / W (so-called phase inversion) to form a discontinuous phase, and the resin is dispersed in the form of particles in an aqueous medium. .

The volume average particle size of the resin particles dispersed in the resin particle dispersion is preferably 0.01 μm or more and 1 μm or less, more preferably 0.08 μm or more and 0.8 μm or less, further 0.1 μm or more and 0.6 μm or less. preferable.
The volume average particle size of the resin particles is a volume with respect to a divided particle size range (channel) using a particle size distribution obtained by measurement with a laser diffraction particle size distribution measuring apparatus (for example, LA-700 manufactured by HORIBA, Ltd.). The cumulative distribution is drawn from the small particle diameter side, and the particle diameter that becomes 50% cumulative with respect to all particles is defined as the volume average particle diameter D50v. The volume average particle size of the particles in the other dispersion is also measured in the same manner.

  5 mass% or more and 50 mass% or less are preferable, and, as for content of the resin particle contained in the resin particle dispersion liquid, 10 mass% or more and 40 mass% or less are more preferable.

  Similar to the resin particle dispersion, for example, a colorant dispersion and a release agent dispersion are also prepared. That is, the dispersion medium, the dispersion method, the volume average particle diameter of the particles, and the content of the particles in the resin particle dispersion are the same in the colorant dispersion and the release agent dispersion.

-Aggregated particle formation process-
Next, the colorant dispersion and the release agent dispersion are mixed together with the resin particle dispersion.
Then, in the mixed dispersion, resin particles, colorant particles, and release agent particles are hetero-aggregated to have resin particles, colorant particles, and release agent particles having a diameter close to the diameter of the target toner particles. Aggregated particles are formed.

Specifically, for example, a flocculant is added to the mixed dispersion, and the pH of the mixed dispersion is adjusted to acidic (for example, pH 2 to 5), and a dispersion stabilizer is added as necessary. The glass particles are heated to a temperature close to the glass transition temperature (specifically, for example, the glass transition temperature of the resin particles is −30 ° C. or higher and the glass transition temperature is −10 ° C. or lower), and the particles dispersed in the mixed dispersion are agglomerated. To form aggregated particles.
In the agglomerated particle forming step, for example, the agglomerated agent is added at room temperature (for example, 25 ° C.) while stirring the mixed dispersion with a rotary shearing homogenizer, and the pH of the mixed dispersion is adjusted to be acidic (for example, pH 2 to 5). In addition, heating may be performed after adding a dispersion stabilizer as necessary.

Examples of the flocculant include a surfactant having a polarity opposite to that of the surfactant contained in the mixed dispersion, such as an inorganic metal salt and a bivalent or higher-valent metal complex. When a metal complex is used as the flocculant, the amount of the flocculant used is reduced and the charging characteristics are improved.
An additive that forms a complex or similar bond with the metal ion of the flocculant may be used together with the flocculant. As this additive, a chelating agent is preferably used.

Examples of inorganic metal salts include metal salts such as calcium chloride, calcium nitrate, barium chloride, magnesium chloride, zinc chloride, aluminum chloride, and aluminum sulfate; inorganic metal salts such as polyaluminum chloride, polyaluminum hydroxide, and calcium polysulfide Polymer; and the like.
A water-soluble chelating agent may be used as the chelating agent. Examples of the chelating agent include oxycarboxylic acids such as tartaric acid, citric acid, and gluconic acid; aminocarboxylic acids such as iminodiacetic acid (IDA), nitrilotriacetic acid (NTA), and ethylenediaminetetraacetic acid (EDTA); .
For example, the addition amount of the chelating agent is preferably 0.01 parts by mass or more and 5.0 parts by mass or less, and more preferably 0.1 parts by mass or more and less than 3.0 parts by mass with respect to 100 parts by mass of the resin particles.

-Fusion / unification process-
Next, the agglomerated particle dispersion in which the agglomerated particles are dispersed is heated to, for example, a glass transition temperature or higher of the resin particles (for example, a temperature of 10 ° C. to 30 ° C. higher than the glass transition temperature of the resin particles). Are fused and united to form toner base particles.

Through the above steps, toner base particles are obtained.
In addition, after obtaining the aggregated particle dispersion liquid in which the aggregated particles are dispersed, the aggregated particle dispersion liquid and the resin particle dispersion liquid in which the resin particles are dispersed are further mixed, and the resin particles are further added to the surface of the aggregated particles. A process of aggregating to adhere to form second aggregated particles, and heating the second aggregated particle dispersion in which the second aggregated particles are dispersed to fuse and coalesce the second aggregated particles. The toner mother particles may be manufactured through a step of forming toner mother particles having a core / shell structure.

  After the coalescence and coalescence process, it is desirable to perform a washing process on the toner base particles formed in the solution. In the washing step, it is preferable to sufficiently perform substitution washing with ion-exchanged water from the viewpoint of chargeability.

  The toner base particles produced by a dry process or a wet process are subjected to a surface modification treatment with polyalkyleneimine. The surface modification treatment is performed, for example, by the following surface modification process.

-Surface modification process-
The surface modification step is, for example, a step of mixing an aqueous dispersion containing toner base particles and a polyalkyleneimine.

  It is desirable to adjust the pH of the aqueous dispersion to 2 to 8. Accordingly, the reaction between the acidic group present on the surface of the toner base particle and the polyalkyleneimine can be efficiently advanced while suppressing unintentional alteration of the constituent material of the toner base particle. The pH of the aqueous dispersion is more preferably 2.5 to 6.5, still more preferably 4 to 5. The pH of the aqueous dispersion is adjusted, for example, by adding 1N hydrochloric acid or the like.

  In the surface modification step, it is desirable to stir the mixed liquid of the aqueous dispersion and polyalkyleneimine for 1 hour to 3 hours. Thereby, the toner base particle surface can be modified more uniformly. The temperature of the mixed solution at the time of stirring is, for example, 15 ° C. to 25 ° C., and may be performed while heating the mixed solution to 25 ° C. to 40 ° C. By carrying out heating to the above temperature range, the surface of the toner base particles can be modified more efficiently.

  The amount of polyalkyleneimine used in the surface modification step is preferably 0.1 to 10 parts by weight, more preferably 0.3 to 6 parts by weight, and 0.5 parts by weight with respect to 100 parts by weight of the particles. Part to 3 parts by mass are more desirable. When the amount of polyalkyleneimine used is within the above range, inconvenience such as elution of polyalkyleneimine from the toner particles after surface modification can be suppressed, and the positive charge amount of the toner can be adjusted to a favorable range.

  After the surface modification step, the surface-modified toner particles are subjected to a washing step, a solid-liquid separation step, and a drying step to obtain dried toner particles. In the washing step, it is preferable to sufficiently perform substitution washing with ion-exchanged water from the viewpoint of chargeability. The solid-liquid separation step is not particularly limited, but suction filtration, pressure filtration, or the like is preferably performed from the viewpoint of productivity. Also, the drying process is not particularly limited, but from the viewpoint of productivity, freeze drying, flash jet drying, fluidized drying, vibration fluidized drying, or the like is preferably performed.

  The toner according to the exemplary embodiment is manufactured, for example, by adding an external additive to dry toner particles and mixing them. Mixing is preferably performed by, for example, a V blender, a Henschel mixer, a Ladyge mixer, or the like. Furthermore, if necessary, coarse toner particles may be removed using a vibration classifier, a wind classifier, or the like.

<Electrostatic image developer>
The electrostatic charge image developer according to the exemplary embodiment includes at least the toner according to the exemplary embodiment. The electrostatic charge image developer according to this embodiment may be a one-component developer including only the toner according to this embodiment, or may be a two-component developer in which the toner and a carrier are mixed.

  The toner according to this embodiment is preferably a non-magnetic one-component toner, that is, the electrostatic charge image developer according to this embodiment is a non-magnetic one-component developer including the toner according to this embodiment. desirable.

  When the electrostatic charge image developer according to the exemplary embodiment is a two-component developer, the mixing ratio of the toner and the carrier (toner: carrier, mass ratio) is preferably 1: 100 to 30: 100, and 3: 100 to 20: 100 is more preferable. A known carrier may be used as the carrier.

<Image Forming Apparatus / Image Forming Method>
An image forming apparatus and an image forming method according to the present embodiment will be described.
The image forming apparatus according to the present embodiment includes an image carrier, a charging unit that charges the surface of the image carrier, an electrostatic image forming unit that forms an electrostatic image on the surface of the charged image carrier, and an electrostatic charge. Development means for containing an image developer and developing the electrostatic image formed on the surface of the image carrier as a toner image with the electrostatic image developer, and the toner image formed on the surface of the image carrier as a recording medium Transfer means for transferring to the surface of the recording medium, and fixing means for fixing the toner image transferred to the surface of the recording medium. The electrostatic charge image developer according to this embodiment is applied as the electrostatic charge image developer.

  In the image forming apparatus according to this embodiment, a charging process for charging the surface of the image carrier, an electrostatic charge image forming process for forming an electrostatic image on the surface of the charged image carrier, and an electrostatic charge according to this embodiment. A developing step of developing an electrostatic charge image formed on the surface of the image carrier as a toner image with an image developer; a transfer step of transferring the toner image formed on the surface of the image carrier to the surface of the recording medium; An image forming method (an image forming method according to the present embodiment) including a fixing step of fixing the toner image transferred onto the surface of the recording medium is performed.

The image forming apparatus according to the present embodiment is a direct transfer type apparatus that directly transfers a toner image formed on the surface of an image carrier to a recording medium; the toner image formed on the surface of the image carrier is transferred to an intermediate transfer member An intermediate transfer type apparatus that primarily transfers the toner image transferred to the surface of the intermediate transfer body and then secondary transfer the toner image to the surface of the recording medium; after the toner image is transferred, the surface of the image carrier before charging is cleaned. A known image forming apparatus such as an apparatus provided with a cleaning unit; an apparatus provided with a charge removing unit that discharges the surface of the image holding member with a discharge light before charging after transferring the toner image;
In the case where the image forming apparatus according to this embodiment is an intermediate transfer type apparatus, for example, the transfer unit intermediately transfers an intermediate transfer body on which a toner image is transferred onto the surface and a toner image formed on the surface of the image holding body. A configuration having primary transfer means for primary transfer onto the surface of the body and secondary transfer means for secondary transfer of the toner image transferred onto the surface of the intermediate transfer body onto the surface of the recording medium is applied.

  In the image forming apparatus according to the present embodiment, for example, the part including the developing unit may have a cartridge structure (process cartridge) that is detachable from the image forming apparatus. As the process cartridge, for example, a process cartridge that accommodates the electrostatic charge image developer according to this embodiment and includes a developing unit is preferably used.

  Hereinafter, an example of the image forming apparatus according to the present embodiment will be described, but the present invention is not limited to this. In the following description, the main part shown in the figure will be described, and the description of other parts will be omitted.

FIG. 1 is a schematic configuration diagram illustrating an image forming apparatus according to the present embodiment.
The image forming apparatus shown in FIG. 1 is a first electrophotographic system that outputs an image of each color of yellow (Y), magenta (M), cyan (C), and black (K) based on color-separated image data. To fourth image forming units 10Y, 10M, 10C, and 10K (image forming means). These image forming units (hereinafter sometimes simply referred to as “units”) 10Y, 10M, 10C, and 10K are arranged in parallel at a predetermined distance from each other in the horizontal direction. These units 10Y, 10M, 10C, and 10K may be process cartridges that can be attached to and detached from the image forming apparatus.

Above each unit 10Y, 10M, 10C, 10K, an intermediate transfer belt (an example of an intermediate transfer member) 20 is extended through each unit. The intermediate transfer belt 20 is provided around a drive roll 22 and a support roll 24 that are in contact with the inner surface of the intermediate transfer belt 20, and travels in a direction from the first unit 10Y to the fourth unit 10K. Yes. A force is applied to the support roll 24 in a direction away from the drive roll 22 by a spring or the like (not shown), and tension is applied to the intermediate transfer belt 20 wound around the support roll 24. An intermediate transfer body cleaning device 30 is provided on the image holding surface side of the intermediate transfer belt 20 so as to face the drive roll 22.
Each unit 10Y, 10M, 10C, 10K developing device (an example of developing means) 4Y, 4M, 4C, 4K has yellow, magenta, cyan, black in toner cartridges 8Y, 8M, 8C, 8K, respectively. Each toner is supplied.

  Since the first to fourth units 10Y, 10M, 10C, and 10K have the same configuration, operation, and action, the yellow image disposed upstream in the intermediate transfer belt traveling direction is displayed here. The first unit 10Y to be formed will be described as a representative.

The first unit 10Y has a photoreceptor 1Y that functions as an image holding member. Around the photoreceptor 1Y, a charging roll (an example of a charging unit) 2Y for charging the surface of the photoreceptor 1Y to a predetermined potential, and the charged surface is exposed by a laser beam 3Y based on a color-separated image signal. Then, an exposure device (an example of an electrostatic image forming unit) 3 that forms an electrostatic image, and a developing device (an example of a developing unit) 4Y that develops the electrostatic image by supplying toner charged to the electrostatic image, developed A primary transfer roll (an example of a primary transfer unit) 5Y that transfers a toner image onto the intermediate transfer belt 20, and a photoconductor cleaning device (an example of a cleaning unit) 6Y that removes toner remaining on the surface of the photoconductor 1Y after the primary transfer. Are arranged in order.
The primary transfer roll 5Y is disposed inside the intermediate transfer belt 20, and is provided at a position facing the photoreceptor 1Y. A bias power source (not shown) for applying a primary transfer bias is connected to the primary transfer rolls 5Y, 5M, 5C, and 5K of each unit. Each bias power source changes the value of the transfer bias applied to each primary transfer roll under the control of a control unit (not shown).

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

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

In the developing device 4Y, an electrostatic charge image developer containing yellow toner is accommodated in the case of a nonmagnetic one-component developer, and an electrostatic charge image developer containing yellow toner and a carrier in the case of a nonmagnetic two-component developer. Is housed. The toner according to the exemplary embodiment is positively charged, but may be further frictionally charged. That is, in the case of a non-magnetic one-component developer, the yellow toner may be frictionally charged on the developing roll by friction with a regulating member that regulates the thickness of the developing roll or the toner layer. In the case of a non-magnetic two-component developer, the yellow toner may be frictionally charged by stirring together with the carrier inside the developing device 4Y. In any case, the yellow toner has the same polarity (positive polarity) as that of the surface of the photoreceptor 1Y and is held on the developing roll.
Then, as the surface of the photoreceptor 1Y passes through the developing device 4Y, the yellow toner is electrostatically attached to the latent image portion on the surface of the photoreceptor 1Y, and the latent image is developed with the yellow toner. The The photoreceptor 1Y on which the yellow toner image is formed continues to run at a predetermined speed, and the toner image developed on the photoreceptor 1Y is conveyed to a predetermined primary transfer position.

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

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

  The intermediate transfer belt 20 onto which the four color toner images have been transferred in multiple ways through the first to fourth units includes the intermediate transfer belt 20, a support roll 24 in contact with the inner surface of the intermediate transfer belt, and an image holding surface of the intermediate transfer belt 20. To a secondary transfer portion composed of a secondary transfer roll (an example of secondary transfer means) 26 arranged on the side. On the other hand, recording paper (an example of a recording medium) P is fed at a predetermined timing into a gap where the secondary transfer roll 26 and the intermediate transfer belt 20 are in contact with each other via a supply mechanism, and the secondary transfer bias is supplied to the support roll. 24. The transfer bias applied at this time is a (+) polarity that is the same polarity as the polarity (+) of the toner, and an electrostatic force from the intermediate transfer belt 20 toward the recording paper P acts on the toner image, and the transfer bias is applied to the intermediate transfer belt 20. The toner image is transferred onto the recording paper P. The secondary transfer bias at this time is determined according to the resistance detected by a resistance detecting means (not shown) for detecting the resistance of the secondary transfer portion, and is voltage-controlled.

  Thereafter, the recording paper P is sent to a pressure contact portion (nip portion) of a pair of fixing rolls in a fixing device (an example of a fixing unit) 28, and the toner image is fixed on the recording paper P to form a fixed image. .

Examples of the recording paper P to which the toner image is transferred include plain paper used in electrophotographic copying machines, printers, and the like. As the recording medium, in addition to the recording paper P, an OHP sheet and the like are also included.
In order to further improve the smoothness of the image surface after fixing, it is preferable that the surface of the recording paper P is also smooth. For example, coated paper in which the surface of plain paper is coated with resin, art paper for printing, etc. Preferably used.

  The recording paper P on which the color image has been fixed is carried out toward the discharge unit, and a series of color image forming operations is completed.

  Hereinafter, an example of the developing device provided in the image forming apparatus according to the present embodiment will be described, but the present invention is not limited to this.

  FIG. 2 is a schematic configuration diagram illustrating an example of a developing device provided in the image forming apparatus according to the present embodiment. The developing device 4 includes a developer accommodating chamber 41, a developer supply roll 42, a developing roll 43, and a toner layer regulating member 44. The developer storage chamber 41, the developer supply roll 42, the development roll 43, and the toner layer regulating member 44 may be integrated as a toner cartridge.

The developer storage chamber 41 stores the developer T. The developer storage chamber 41 may be provided with a stirring member 45 that stirs the developer T.
The developer supply roll 42 is provided so as to be in contact with the developer T accommodated in the developer accommodating chamber 41 and close to or in contact with the developing roll 43, and the developer T in the developer accommodating chamber 41 is provided. Is supplied to the surface of the developing roll 43.
The developing roll 43 holds the developer T supplied from the developer supply roll 42, carries the developer T to the photosensitive member 1, and develops (develops the electrostatic latent image formed on the surface of the photosensitive member 1. To form a toner image.
The toner layer regulating member 44 regulates the thickness of the toner layer on the developing roll 43.

  The developer supply roll 42 is, for example, a roll having a sponge layer formed of a foam material such as urethane rubber as a surface layer on a metallic cylinder. The sponge layer may contain conductive particles such as carbon black.

  The developing roll 43 is, for example, a roll having an elastic sleeve made of rubber on a metallic cylinder; a roll of conductive urethane rubber to which conductive particles such as carbon black are added; oxidation, metal plating, polishing, blasting A metal roll subjected to a surface treatment such as a rubber roll or a metal roll whose surface is coated with a resin.

  The developing roll 43 preferably has a negatively chargeable roll surface from the viewpoint of frictionally charging the toner when rubbed with the positively charged toner. Examples of the developing roll 43 include a roll having an elastic sleeve made of silicone rubber to which a fluorine-containing compound is added. Examples of the fluorine-containing compound include fluorinated olefin-hydrocarbon olefin copolymers such as polytetrafluoroethylene, tetrafluoroethylene, vinylidene tetrafluoride, and fluorinated ethylene-propylene copolymers, perfluoroalkoxy resins, fluoro Examples include (meth) acrylate- (meth) acrylate copolymers.

  The toner layer regulating member 44 is a plate-like member made of rubber such as silicone rubber or urethane rubber; a plate-like member made of metal such as SUS or aluminum; and the surface of the plate-like member made of rubber or metal is plated. A member: a member obtained by coating the surface of a rubber or metal plate member with a resin such as an acrylic resin, a phenol resin, or a urethane resin;

  From the viewpoint of frictionally charging the toner layer regulating member 44 when the toner is rubbed with the positively charged toner, the surface of the portion in contact with the toner is desirably negatively charged. Examples of the toner layer regulating member 44 include a plate-like member made of silicone rubber to which a fluorine-containing compound is added. Examples of the fluorine-containing compound include fluorinated olefin-hydrocarbon olefin copolymers such as polytetrafluoroethylene, tetrafluoroethylene, vinylidene tetrafluoride, and fluorinated ethylene-propylene copolymers, perfluoroalkoxy resins, fluoro Examples include (meth) acrylate- (meth) acrylate copolymers.

<Process cartridge / toner cartridge>
The process cartridge according to this embodiment will be described.
The process cartridge according to the present embodiment accommodates the electrostatic image developer according to the present embodiment, and develops the electrostatic image formed on the surface of the image carrier as a toner image by the electrostatic image developer. And a process cartridge that can be attached to and detached from the image forming apparatus.

  The process cartridge according to the present embodiment is not limited to the above configuration, and is selected from a developing device and other means such as an image carrier, a charging unit, an electrostatic charge image forming unit, and a transfer unit, if necessary. And at least one of the above may be provided.

  Hereinafter, an example of the process cartridge according to the present embodiment will be shown, but the present invention is not limited to this. In the following description, the main part shown in the figure will be described, and the description of other parts will be omitted.

FIG. 3 is a schematic configuration diagram showing a process cartridge according to the present embodiment.
The process cartridge 200 shown in FIG. 3 is provided around the photosensitive member 107 and the photosensitive member 107 by, for example, a housing 117 provided with an attachment rail 116 and an opening 118 for exposure. A charging roller 108 (an example of a charging unit), a developing device 111 (an example of a developing unit), and a photoconductor cleaning device 113 (an example of a cleaning unit) are integrally combined and held to form a cartridge. Yes.
In FIG. 3, 109 is an exposure device (an example of an electrostatic charge image forming unit), 112 is a transfer device (an example of a transfer unit), 115 is a fixing device (an example of a fixing unit), and 300 is a recording paper (an example of a recording medium). Is shown.

Next, the toner cartridge according to this embodiment will be described.
The toner cartridge according to the present exemplary embodiment is a toner cartridge that accommodates the toner according to the present exemplary embodiment and is detachable from the image forming apparatus. The toner cartridge contains toner for replenishment to be supplied to the developing means provided in the image forming apparatus.

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

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist thereof.

  In the following, “part” and “%” are based on mass unless otherwise specified.

[Synthesis of polyester resin (1)]
・ Terephthalic acid: 30 mol part ・ Fumaric acid: 70 mol part ・ Bisphenol A ethylene oxide adduct: 5 mol part ・ Bisphenol A propylene oxide adduct: 95 mol part Stirrer, nitrogen introduction tube, temperature sensor, and rectifying column The above material was charged into a 5 liter flask equipped with the above, the temperature was raised to 220 ° C. over 1 hour, and 1 part of titanium tetraethoxide was added to 100 parts of the material. The temperature was raised to 230 ° C. over 0.5 hours while distilling off the produced water, and the dehydration condensation reaction was continued at that temperature for 1 hour, and then the reaction product was cooled. Thus, a polyester resin (1) having a weight average molecular weight of 18,000, an acid value of 15 mgKOH / g, and a glass transition temperature of 60 ° C. was synthesized.

[Preparation of toner base particles (1)]
-Preparation of resin particle dispersion-
Polyester resin (1): 160 parts Ethyl acetate: 230 parts Sodium hydroxide aqueous solution (0.3N): 0.1 part The above materials are put in a 1000 ml separable flask and heated at 70 ° C, and a three-one motor ( A resin mixed solution was prepared by stirring with Shinto Kagaku Co.). While further stirring this resin mixture, 373 parts of ion-exchanged water was gradually added, phase inversion emulsification was carried out, and the solvent was removed to prepare a resin particle dispersion (solid content 30%).

-Preparation of release agent dispersion-
-Paraffin wax (HNP-9 manufactured by Nippon Seiwa Co., Ltd.): 50 parts-Anionic surfactant (Neogen RK, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.): 1 part-Ion-exchanged water: 200 parts And then dispersed using a homogenizer (Ultra Turrax T50 manufactured by IKA) and then dispersed using a Menton Gorin high-pressure homogenizer (manufactured by Gorin) to release the release agent particles having a volume average particle diameter of 200 nm. A mold dispersion (solid content 20%) was prepared.

-Preparation of colorant dispersion-
Carbon black (Regal 330 manufactured by Cabot): 50 parts Anionic surfactant (Neogen RK manufactured by Daiichi Kogyo Seiyaku Co., Ltd.): 1 part Ion-exchanged water: 200 parts The above materials were mixed and homogenizer (Ultrata manufactured by IKA) A colorant dispersion (solid content 20%) in which colorant particles were dispersed was prepared by dispersing for 10 minutes using Lux T50).

-Preparation of toner base particles-
Resin particle dispersion (solid content 30%): 480 parts Release agent dispersion (solid content 20%): 70 parts Colorant dispersion (solid content 20%): 50 parts Charge control agent (Orient Chemical) Bontron P-51 (20% aqueous dispersion): 10 parts Anionic surfactant (TaycaPower, 20% aqueous solution): 2 parts The above material was placed in a round stainless steel flask and homogenizer (IKA). Dispersion was carried out using Ultra Turrax T50). Subsequently, 0.1N nitric acid was added to adjust the pH to 3.5, and 30 parts of an aqueous nitric acid solution having a polyaluminum chloride concentration of 10% by mass was added. Subsequently, after dispersing at 30 ° C. using a homogenizer, the mixture was heated to 40 ° C. in a heating oil bath and held for 30 minutes. Thereafter, 100 parts of the resin particle dispersion was gradually added and held for 30 minutes. Then, after adding 0.1N sodium hydroxide aqueous solution and adjusting pH to 8.5, it heated to 85 degreeC, continuing stirring, and hold | maintained for 180 minutes. After confirming that the aggregated particles were fused with an optical microscope, it was cooled to 20 ° C. at a rate of 1 ° C./min. After cooling, the particles were separated by filtration, sufficiently washed with ion exchange water, and dried to obtain toner base particles (1) having a volume average particle diameter of 7 μm.

[Preparation of toner base particles (2)]
Polyester resin (1): 87 parts Carbon black (Regal 330 manufactured by Cabot Corporation): 7 parts Paraffin wax (HNP-9 manufactured by Nippon Seiwa Co., Ltd.): 5 parts Charge control agent (Bontron P-51 manufactured by Orient Chemical Co., Ltd.) ): 1 part The above material is kneaded with an extruder, pulverized with a surface pulverizer, fine particles and coarse particles are classified with a wind classifier, and toner base particles (2) having a volume average particle diameter of 7 μm Got.

[Preparation of Toner Particles (1)]
The toner base particles (1) were dispersed in ion-exchanged water so as to have a solid content of 30%, and the pH was adjusted to 4.0 by adding 1N hydrochloric acid. Polyethyleneimine (number average molecular weight 70000) was added dropwise thereto while stirring the dispersion. Polyethyleneimine was added to 1 part with respect to 100 parts of toner base particles. After stirring for 2 hours with a stirring blade, the dispersion was subjected to solid-liquid separation, and further subjected to washing treatment by repeated re-dispersion in ion-exchanged water and solid-liquid separation. When the pH of the filtrate reached 7.5, the washing treatment was terminated, and the solid content was dried with a vacuum dryer for 12 hours to obtain toner particles (1) having a volume average particle diameter of 7 μm.

[Preparation of Toner Particles (2)]
Toner particles (2) were prepared in the same manner as the toner particles (1) except that the toner mother particles (2) were used instead of the toner mother particles (1).

[Preparation of oil-treated silica particles]
Silica particles surface-treated with dimethyl silicone oil (KF-96L manufactured by Shin-Etsu Chemical Co., Ltd.) were prepared by the sol-gel method. The amount of free oil is adjusted by adjusting the amount of oil used in the surface treatment, the number average particle size is adjusted by pulverization, and the oil-treated silica particles (1) to (10) shown in Table 1 below are prepared. Prepared.

(Preparation of zinc stearate particles)
After adding 1422 parts of stearic acid to 10000 parts of ethanol and mixing at a liquid temperature of 75 ° C., 507 parts of zinc hydroxide was added little by little, followed by stirring and mixing for 1 hour after completion of the addition. Thereafter, the solution was cooled to 20 ° C., the product was filtered off to remove ethanol and reaction residues, and the taken out solid product was dried at 150 ° C. for 3 hours using a heating type vacuum dryer. After taking out from the dryer and allowing to cool, a solid product of zinc stearate was obtained. Since the obtained solid had a large particle size, the volume average particle size was prepared by pulverizing with a small pulverizer (SK-M10 manufactured by Kyoritsu Riko Co., Ltd.). The conditions for the grinding treatment were adjusted to prepare zinc stearate particles (1) to (6) shown in Table 2 below.

<Examples A1 to A6, Comparative Example A0, Comparative Examples A1 to A2>
The toner particles, oil-treated silica particles, zinc stearate particles, and calcined amorphous silica (TG828F manufactured by Cabot) were combined and mixed as shown in Table 3 to prepare a toner (one-component developer).
In Example A6, the toner and the carrier were further mixed so that the toner concentration was 8% to prepare a two-component developer. The carrier used here was 100 parts of 50 μm Mn—Sr core, 7.5 parts of a silicone resin (SR2411 manufactured by Toray-Dow Corning) and 100 parts of toluene, and then the solvent was distilled off. It was prepared by stirring at 1 ° C. for 1 hour to cure the resin.

<Examples B1-B8, Comparative Examples B1-B2>
Toner particles, oil-treated silica particles, zinc stearate particles, and calcined amorphous silica (TG828F manufactured by Cabot) were combined and mixed as shown in Table 4 to prepare a toner (one-component developer).

<Evaluation>
[Toner stain 1]
For evaluation of one-component developer, DocuPrint P300d manufactured by Fuji Xerox Co., Ltd., and for evaluation of two-component developer, DocuCenter Color 500 manufactured by Fuji Xerox Co., Ltd. was modified so that a potential suitable for evaluation could be applied.
Under high temperature and high humidity (35 ° C / 85%), XC4200 paper made by XEROX was used, and 8000 sheets of paper were run with intermittent printing of 1 sheet / 14 seconds. The dirt was observed with the naked eye. The evaluation results are shown in Tables 3 and 4.
-Criteria-
A: Toner contamination is not recognized.
B: Very slight toner contamination is observed.
C: A level at which slight toner contamination is observed but does not cause a problem in practical use.
D: Level at which toner contamination is clearly recognized and causes practical problems.

[Toner stain 2]
Changed the toner layer regulating member of the developing device of DocuPrint P300d manufactured by Fuji Xerox Co. to a member made of dimethyl silicone rubber containing 1/2 mass% of the fluorine-containing compound from the standard machine. (The size of the members was the same). Using this as an evaluation machine, a one-component developer was evaluated in the same manner as in Evaluation 1. The evaluation results are shown in Tables 3 and 4.

[Charge amount]
A one-component developer (toner) before and after the paper running is collected from a toner container, and a charge amount / particle size distribution measuring device (Espert Analyzer E-SPART-2 manufactured by Hosokawa Micron Corporation) is used to measure the gas pressure: About 3000 measurements were performed under the conditions of 0.4 kgf / cm ² and field voltage: 150V. The evaluation results are shown in Tables 3 and 4.

1Y, 1M, 1C, 1K, photoconductor (an example of an image carrier)
2Y, 2M, 2C, 2K, charging roll (an example of charging means)
3. Exposure device (an example of electrostatic charge image forming means)
3Y, 3M, 3C, 3K Laser beams 4Y, 4M, 4C, 4K Developing device (an example of developing means)
5Y, 5M, 5C, 5K primary transfer roll (an example of primary transfer means)
6Y, 6M, 6C, 6K Photoconductor cleaning device (an example of cleaning means)
8Y, 8M, 8C, 8K Toner cartridge 10Y, 10M, 10C, 10K Image forming unit 20 Intermediate transfer belt (an example of an intermediate transfer member)
22 Drive roll 24 Support roll 26 Secondary transfer roll (an example of secondary transfer means)
28 Fixing device (an example of fixing means)
30 Intermediate transfer member cleaning device P Recording paper (an example of a recording medium)

DESCRIPTION OF SYMBOLS 1 Photoconductor 4 Developing apparatus 41 Developer storage chamber 42 Developer supply roll 43 Developing roll 44 Toner layer regulating member 45 Stirring member T Developer

107 photoconductor (an example of an image carrier)
108 Charging roll (an example of charging means)
109 Exposure apparatus (an example of electrostatic charge image forming means)
111 Developing device (an example of developing means)
112 Transfer device (an example of transfer means)
113 photoconductor cleaning device (an example of cleaning means)
115 Fixing device (an example of fixing means)
116 Mounting rail 117 Housing 118 Opening 200 for exposure Process cartridge 300 Recording paper (an example of a recording medium)

Claims (11)

Toner particles surface-modified with polyalkyleneimine;
Fatty acid metal salt particles having a volume average particle diameter of 8 μm or more and 20 μm or less;
Inorganic particles surface-treated with silicone oil and having a free oil amount of 0.1% by mass or more and 1.5% by mass or less;
A toner for developing an electrostatic charge image.   The toner for developing an electrostatic charge image according to claim 1, wherein the number average particle diameter of the inorganic particles is 20 nm or more and 60 nm or less.   The electrostatic image developing toner according to claim 1, wherein the inorganic particles are silica particles.   The electrostatic image developing toner according to claim 1, wherein the polyalkyleneimine is polyethyleneimine.   The toner for developing an electrostatic charge image according to any one of claims 1 to 4, which is a non-magnetic one-component toner.   An electrostatic charge image developer comprising the electrostatic charge image developing toner according to claim 1.   The electrostatic charge image developer according to claim 6, which is a non-magnetic one-component developer. Containing the toner for developing an electrostatic charge image according to any one of claims 1 to 5,
A toner cartridge to be attached to and detached from the image forming apparatus. A developing means for containing the electrostatic charge image developer according to claim 6 or 7 and developing the electrostatic charge image formed on the surface of the image carrier as a toner image by the electrostatic charge image developer,
A process cartridge attached to and detached from the image forming apparatus. An image carrier,
Charging means for charging the surface of the image carrier;
An electrostatic charge image forming means for forming an electrostatic charge image on the surface of the charged image carrier;
Development means for containing the electrostatic charge image developer according to claim 6 or 7 and developing the electrostatic charge image formed on the surface of the image carrier as a toner image by the electrostatic charge image developer;
Transfer means for transferring a toner image formed on the surface of the image carrier to the surface of a recording medium;
Fixing means for fixing the toner image transferred to the surface of the recording medium;
An image forming apparatus comprising: A charging step for charging the surface of the image carrier;
An electrostatic charge image forming step of forming an electrostatic charge image on the surface of the charged image carrier;
A developing step of developing an electrostatic charge image formed on the surface of the image carrier as a toner image by the electrostatic charge image developer according to claim 6 or 7,
A transfer step of transferring a toner image formed on the surface of the image carrier to the surface of a recording medium;
A fixing step of fixing the toner image transferred to the surface of the recording medium;
An image forming method comprising: