JP2002169330A - Toner for developing electrostatic latent image, its producing method, image forming method and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide toner for developing an electrostatic latent image by which the fluctuation of image density caused by temperature and humidity environment at the time of using is eliminated by preventing the wear of a cleaning blade and image blur or the like caused by toner's coming off or toner's adhering to the surface of a photoreceptor at the time of leaning, and to provide its producing method, an image forming method or an image forming device using the same. SOLUTION: The toner for developing an electrostatic latent image in which toner particles are obtained by forming particles in a water medium is provided and the toner incorporates fatty acid calcium salt as an additive.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner for developing an electrostatic latent image, a method of manufacturing the same, and an image forming method or an image forming apparatus using the same.

[0002]

2. Description of the Related Art Today, copiers that require high speed and high image quality,
In most cases, a printer forms an image by an electrophotographic method using a toner for developing an electrostatic latent image.

[0003] This is because the electrophotographic system can form high-quality images at high speed and has stability that can withstand long-term use. However, the demand level has been steadily increasing in recent years. Improvement research is being actively conducted.

One of the major themes is the pursuit of a more stable image forming method that is resistant to repeated use over a long period of time and environmental changes during use.
For this purpose, it is necessary to comprehensively improve the durability of the electrophotographic photosensitive member (also simply referred to as a photosensitive member) and its surroundings, which act on the photosensitive member and which contribute to image formation.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to meet the above demands. That is, an object of the present invention is to provide a method for improving the durability of a photoconductor itself, a toner for developing an electrostatic latent image acting on the photoconductor itself, and a cleaning device when the photoconductor is repeatedly used. More specifically, an electrostatic latent image developing toner that eliminates wear of a cleaning blade, slippage of toner on a photoreceptor surface during cleaning or image blur due to toner sticking, and fluctuation of image density due to temperature and humidity environment during use. And an image forming method or an image forming apparatus using the same.

[0006]

The inventors of the present invention have made intensive studies and as a result, the object of the present invention has been attained by adopting the following constitution.

[1] An electrostatic latent image developing toner obtained by forming toner particles in an aqueous medium, wherein the toner contains a fatty acid calcium salt as an external additive. An electrostatic latent image developing toner.

[2] The fatty acid calcium salt has a moisture content of 0.1 to 2.5% by mass and a free fatty acid content of 0.01 to
The toner for developing an electrostatic latent image according to [1], wherein the amount is 0.7% by mass.

[3] The toner for developing an electrostatic latent image according to [1] or [2], wherein the fatty acid calcium salt is calcium stearate.

[4] It is characterized by being obtained by aggregating and fusing at least resin particles in an aqueous medium.
The toner for developing an electrostatic latent image according to any one of [3].

[5] The toner has an average particle diameter of 0.1 to 0.1.
The average primary particle diameter is 5 to 5 μm on the surface of the organic fine particles.
The toner for developing an electrostatic latent image according to any one of [1] to [4], which further comprises, as an external additive, inorganic / organic composite fine particles having 100 nm of inorganic fine particles fixed thereto.

[6] The number average particle diameter of the toner is 3 to 8 μm.
m, the coefficient of variation of the shape coefficient is 16% or less, and the coefficient of number variation in the number particle size distribution is 27% or less, The electrostatic latent image according to any one of [1] to [5], Image developing toner.

[7] The number average particle diameter of the toner is 3 to 8 μm.
m, and a ratio of toner particles having a shape factor in a range of 1.0 to 1.6 is 65% by number or more, wherein the electrostatic charge according to any one of [1] to [5], Latent image developing toner.

[8] The number average particle diameter of the toner is 3 to 8 μm
m, and the ratio of toner particles having a shape factor in the range of 1.2 to 1.6 is 65% by number or more, wherein the ratio is 65% by number or more. An electrostatic latent image developing toner.

[0015]

[9] The toner has a number average particle diameter of 3 to 8 μm
m, and the ratio of toner particles having no corners is 50% by number or more, The toner for developing an electrostatic latent image according to any one of [1] to [5].

[10] Assuming that the particle size of the toner is D (μm), the natural logarithm lnD is plotted on the abscissa, and the abscissa is set to 0.1.
The relative frequency (m1) of the toner particles included in the most frequent class in the histogram showing the number-based particle size distribution divided into a plurality of classes at 23 intervals, and the toner particles included in the class having the second highest frequency after the most frequent class Wherein the sum (M) with the relative frequency (m2) is 70% or more.
The toner for developing an electrostatic latent image according to any one of [5].

[11] The method according to any one of [1] to [5], wherein the ratio of the toner having no corners is 50% by number or more and the number variation coefficient in the number particle size distribution is 27% or less. The toner for developing an electrostatic latent image according to the above.

[12] The toner is characterized in that the proportion of toner particles having a shape coefficient in the range of 1.2 to 1.6 is 65% by number or more and the coefficient of variation of the shape coefficient is 16% or less. The toner for developing an electrostatic latent image according to any one of [1] to [5].

[13] Salting-out, agglomeration of the composite resin particles obtained by multi-stage polymerization of the toner and the colorant particles,
The toner according to any one of [1] to [12], which is a toner obtained by fusing, wherein a toner containing a release agent in a region other than the outermost layer of the composite resin particles is used. For developing electrostatic latent images.

[14] Gel permeation chromatography (GPC) peaks or shoulders of at least 100,000 to 1,000,000,
The toner for developing an electrostatic latent image according to any one of [1] to [13], wherein a toner resin existing in the range of 00 to 50,000 is used.

[15] Gel permeation chromatography (GPC) peaks or shoulders of at least 100,000 to 1,000,000,
000 to 100,000 and 1,000 to 25,000
[1] characterized by using a toner resin present in [1]
The toner for developing an electrostatic latent image according to any one of items [13] to [13].

[16] The method according to any one of [1] to [15], which comprises a resin, a release agent and a colorant, and has a crushing strength index of 0.1 to 0.8. An electrostatic latent image developing toner.

[17] After the electrostatic latent image formed on the organic photoreceptor is developed with a developer containing a toner, and the toner image visualized by the development is transferred from the organic photoreceptor to a transfer material. In an image forming apparatus having a cleaning device for removing a toner remaining on an organic photoreceptor, the toner may use the toner for developing an electrostatic latent image according to any one of [1] to [16]. Characteristic image forming apparatus.

[18] The organic photoreceptor has a structure in which a photosensitive layer is provided on a conductive support, and the surface layer of the photosensitive layer contains polycarbonate having an average molecular weight of 40,000 or more. [17] The image forming apparatus according to [17].

[19] After developing the electrostatic latent image formed on the organic photoreceptor with a developer containing toner, and transferring the toner image visualized by the development from the organic photoreceptor to a transfer material An image forming method including a cleaning unit for removing a toner remaining on an organic photoreceptor;
An image forming method characterized by using the toner according to any one of [16] to [16].

[20] The organic photoreceptor has a constitution in which a photosensitive layer is provided on a conductive support, and the surface layer of the photosensitive layer contains polycarbonate having an average molecular weight of 40,000 or more. [19] The image forming method according to the above.

[21] At least toner particles are formed by forming particles in an aqueous medium, and after drying the particles, 0.005 to 0.3% by mass of fatty acid calcium salt particles are externally added. A method for producing a latent image developing toner.

The fatty acid calcium used in the present invention is specifically as follows.

Calcium undecylate, calcium laurate, calcium tridecylate, calcium dodecylate, calcium myristate, calcium palmitate, calcium pentadecylate, calcium stearate, calcium behenate, calcium heptadecylate,
Long-chain fatty acid calcium such as calcium arachinate, calcium montanate, calcium oleate, calcium linoleate, calcium arachidate, calcium behenate and the like can be mentioned. The fatty acid component may be a single fatty acid or a mixture of several fatty acids. Among them, calcium stearate is particularly preferred. The external addition amount is preferably 0.005 to 0.3% by mass of the toner mass.

The production method includes a melting method in which a fatty acid and calcium oxide or calcium hydroxide are melt-reacted at a temperature equal to or higher than the melting point of the fatty acid calcium salt to be produced, a slurry of fatty acid and calcium oxide or calcium hydroxide, Any of a semi-melting method in which the calcium salt is semi-molten below the melting point thereof, a double decomposition method in which an aqueous solution of an inorganic metal salt is added to an aqueous solution of a fatty acid sodium salt, and sodium is replaced with calcium, and the like may be used.

The preferred amount of water and free fatty acid contained in the case of fatty acid calcium is substantially as follows.

The water content of the fatty acid calcium is preferably from 0.1 to 2.5% by mass, particularly preferably from 0.3 to 1.2% by mass, from the viewpoint of enhancing the humidity stability of charging. The amount of free fatty acid is preferably 0.01 to 0.7% by mass,
0.5% by mass is particularly preferred. When the amount is more than 0.5% by mass, there is a possibility that a charging member such as a carrier and a developer carrying member (developing roll surface) may be contaminated. When the amount is less than 0.05% by mass, blade wear tends to increase. Yes,
The life of the cleaning blade may be shortened.

The method of measuring the amount of water and the amount of free fatty acid contained in the fatty acid calcium was carried out as follows.

1) Measurement of water content The water content is measured by the Karl Fischer method.

As a specific measuring method, a measuring method using a Hiranuma trace moisture meter (AQS-712: manufactured by Hiranuma Sangyo) under the following conditions can be mentioned.

Sample heating temperature: 110 ° C. Sample heating time: 1 minute Nitrogen gas flow rate: 150 ml / min 2) Measurement of free fatty acid 1 g of a sample was precisely weighed, and ethanol: ethyl ether:
The mixture was dissolved in one mixture, neutralized and titrated with an aqueous solution of potassium hydroxide using phenolphthalein as an indicator, and the content of free fatty acids was expressed in terms of mass percentage of stearic acid.

In the present invention, as an external additive of the toner,
Inorganic / organic composite fine particles as abrasive particles are preferably used. The inorganic / organic composite fine particles have a spherical shape, the surface is an inorganic fine powder having a high hardness, and the core uses relatively elastic organic fine particles. Demonstrate stable cleaning performance without causing damage to the photoconductor and the cleaning blade.

The primary average particle diameter of the inorganic fine particles constituting the inorganic / organic composite fine particles is preferably from 5 to 100 nm from the viewpoint of improving the cleaning property, the polishing property and the filming resistance. In addition, the primary average particle diameter of the inorganic fine particles refers to the number-based average particle diameter measured by image analysis under observation with a scanning electron microscope.

The constituent materials of the inorganic fine particles include silicon oxide, titanium oxide, aluminum oxide, zinc oxide, zirconium oxide, cerium oxide, tungsten oxide, antimony oxide, copper oxide, tellurium oxide, manganese oxide, barium titanate, and titanate. Strontium, magnesium titanate, silicon nitride, carbon nitride and the like are used.

The organic fine particles constituting the inorganic / organic composite fine particles are preferably resin particles composed of an acrylic acid polymer, a styrene polymer, a styrene-acrylic acid copolymer or the like.

The acrylic acid polymer constituting the organic fine particles is a homopolymer or a copolymer obtained by polymerizing a monomer selected from acrylic acid or an acrylic ester, methacrylic acid or a methacrylic ester. . Examples of the acrylic acid monomer used to obtain such an acrylic acid polymer include acrylic acid, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, propyl acrylate, and n-acrylic acid. Octyl, dodecyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, α-chloromethyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, methacrylic acid Propyl, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, lauryl methacrylate, 2-methacrylic acid
Examples include ethylhexyl, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, and diethylaminoethyl methacrylate. An acrylic acid-based polymer can be obtained from one or more of the above-described acrylic acid-based monomers. In the present invention, one or more other monomers are copolymerized as necessary. It may be something. In this case, it is preferable to use the acrylic acid-based monomer in a proportion of 50% by mass or more in the monomer composition.

The styrene acid monomers used to obtain the styrene acid polymer constituting the organic fine particles include:
Styrene, o-methylstyrene, m-methylstyrene,
p-methylstyrene, α-methylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p-tert-butylstyrene, pn-hexylstyrene, pn-octylstyrene, pn-
Nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, 3,4-dichlorostyrene, and the like can be mentioned. A styrene-based polymer can be obtained from one or more of the above-mentioned styrene-based monomers. In the present invention, one or more other monomers are copolymerized as necessary. There may be. In this case, it is preferable to use a styrene-based monomer in a proportion of 50% by mass or more in the monomer composition.

The styrene-acrylic acid copolymer constituting the organic fine particles is obtained by using one or more of the above-mentioned acrylic monomers and one or more of the above-mentioned styrene monomers. However, if necessary, one other monomer
It may be one or two or more copolymerized. In this case, in the monomer composition, it is preferable to use the acrylic acid-based monomer and the styrene-based monomer in a total amount of 50% by mass or more.

Examples of the other monomers include acrylic compounds such as acrylonitrile, methacrylonitrile, and acrylamide; vinyl esters such as vinyl acetate, vinyl butyrate and vinyl benzoate; and vinyl ethers such as vinyl methyl ether and vinyl ethyl ether. , Vinyl ketones such as vinyl methyl ketone, dienes such as butadiene and isoprene, unsaturated carboxylic acids such as maleic acid and fumaric acid, and the like.

The average particle diameter of the organic fine particles constituting the inorganic / organic composite fine particles is preferably from 0.1 to 5.0 μm, particularly preferably from 0.2 to 3.0 μm, from the viewpoints of improvement in cleaning properties and stability of triboelectric charging. 0 μm is preferred. The average particle size of the organic fine particles can be determined by a laser diffraction particle size distribution analyzer “HELOS” equipped with a wet disperser (Sympatech (SY)
MATEC) (volume-based average particle size). However, before measurement, the number of organic fine particles was 10 mg.
Was dispersed in 50 ml of water together with a surfactant, and then subjected to a pretreatment for 1 to 10 minutes with an ultrasonic homogenizer (output: 150 W) while paying attention to reaggregation due to heat generation.

The inorganic / organic composite fine particles are constituted by fixing inorganic fine particles treated with the above-mentioned specific treatment compound on the surface of the organic fine particles. Here, the term “fixed” refers to a state in which the length of a portion of the inorganic fine particles embedded in the organic fine particles is 5% to 95%, instead of being simply attached to the organic fine particles by the electrostatic force. Such a condition
It can be confirmed by observing the surface of the inorganic / organic composite fine particles with a transmission electron microscope or a normal electron microscope. In fixing the inorganic fine particles to the surface of the organic fine particles, it is preferable to first make the organic fine particles spherical, and then to fix the inorganic fine particles to the surface of the organic fine particles.
This is because when the organic fine particles are spherical, the inorganic fine particles are uniformly fixed, and the release of the inorganic fine particles is effectively prevented. Means for spheroidizing the organic fine particles include a method in which the organic fine particles are once melted by heat and then spray granulation, a method in which the hot-melted organic fine particles are jetted into water and spheroidized, a suspension polymerization method, A method of synthesizing spherical organic fine particles by an emulsion polymerization method may, for example, be mentioned.

Means for fixing the inorganic fine particles on the surface of the organic fine particles include a method of mixing the organic fine particles and the inorganic fine particles and then applying heat, and a so-called mechanochemical method of mechanically fixing the inorganic fine particles on the surface of the organic fine particles. Method is used. Specifically, the organic fine particles and the inorganic fine particles are mixed and stirred and mixed by a Henschel mixer, a V-type mixer, a turbular mixer, etc., and the inorganic fine particles are adhered to the surface of the organic fine particles by electrostatic force. A method in which the organic fine particles having the fine particles attached thereto are introduced into a heat treatment apparatus such as a nitro atomizer or a spray drier, and heat is applied to soften the surface of the organic fine particles to fix the inorganic fine particles to the surface. After attaching the inorganic fine particles, the impact-type pulverizer is modified to fix the inorganic fine particles on the surface of the organic fine particles by using a device capable of imparting mechanical energy, for example, a device such as an ang mill, a free mill, and a hybridizer. And the like.

In obtaining the inorganic / organic composite fine particles, the compounding amount of the inorganic fine particles with respect to the organic fine particles may be an amount capable of uniformly covering the surface of the organic fine particles. Specifically, although it depends on the specific gravity of the inorganic fine particles, it is usually 5 to 100% by mass, preferably 5 to 80% by mass with respect to the organic fine particles.
Inorganic fine particles are used in a ratio of mass%. If the proportion of the inorganic fine particles is too small, the cleaning property tends to decrease, and if the proportion of the inorganic fine particles is too large, the inorganic fine particles are easily released.

The above-mentioned inorganic / organic composite fine particles are added to and mixed with the colored particles to form a toner. The mixing ratio of the inorganic / organic composite fine particles is determined from the viewpoints of improvement in cleaning properties and stability of triboelectric charging. 0.01 to colored particles
5.0 mass% is preferable, and especially 0.01 to 2.0 mass% is preferable.

Examples of the abrasive externally added as an abrasive other than the inorganic / organic composite fine particles include calcium titanate powder, barium titanate powder, magnesium titanate powder, strontium titanate powder, cerium oxide powder,
There are zirconium oxide powder, titanium oxide powder, aluminum oxide powder, boron carbide powder, silicon carbide powder, silicon oxide powder, diamond powder and the like, and these may be used alone or in combination. Of these, strontium titanate powder and cerium oxide powder are particularly preferably used.

The amount of the abrasive is preferably 0.1 to 10.0 parts by mass, more preferably 0.2 to 5.0 parts by mass, based on 100 parts by mass of the toner particles.

[0052]

BEST MODE FOR CARRYING OUT THE INVENTION The members and compounds constituting the requirements of the present invention will be further described.

The cleaning device used in the present invention comprises:
It is of a cleaning blade type.

The cleaning blade used in the present invention is preferably an elastic rubber blade. The physical properties of the cleaning blade are controlled simultaneously by controlling the rubber hardness and the rebound resilience. Can be suppressed. Blade J at 25 ± 5 ° C
When the ISA hardness is less than 65, reversal of the blade is likely to occur, and when it is more than 80, the cleaning performance decreases. When the rebound resilience exceeds 80, reversal of the blade tends to occur, and when the rebound resilience is 20 or less, the cleaning performance deteriorates. More preferable rebound resilience is 20 or more and 80.
It is as follows. The Young's modulus is preferably in the range of 294 to 588 N / cm ² . It should be noted that JISA in the present invention
Both the hardness and the rebound resilience are measured based on the vulcanized rubber physical test method of JIS K6301. The value of the rebound resilience indicates%.

As the material of the elastic rubber blade used for the cleaning blade, urethane rubber, silicone rubber, fluorine rubber, chloropyrene rubber, butadiene rubber and the like are known. Among these, urethane rubber is other rubber. It is particularly preferred in that it has excellent wear characteristics as compared with For example, urethane rubber obtained by reacting and curing a polycaprolactone ester and a polyisocyanate described in JP-A-59-30574 is particularly preferable.

In the present invention, the method of fixing the elastic rubber blade to the support member is preferably such that the elastic rubber blade is substantially held by the support member on the photosensitive member contact surface side. By employing such a holding method, torque fluctuation of the cleaning blade can be stabilized.

The condition for properly pressing the elastic rubber blade against the surface of the photoreceptor is determined by a delicate balance of various characteristics, and is quite narrow. It depends on the characteristics such as the thickness of the elastic rubber blade and the setting requires accuracy. However, the elastic rubber blades cannot be always set under appropriate conditions because the thickness of the elastic rubber blades may vary at the time of manufacture. May deviate from the appropriate area. Particularly when combined with an organic photosensitive layer using a high molecular weight binder resin, image defects such as filming and black spots are liable to occur when the organic photosensitive layer deviates from an appropriate region.

Therefore, it is necessary to take measures for canceling the variation in the characteristics of the elastic rubber blade. Even if the thickness of the elastic rubber blade varies, it does not affect the pressing force against the photosensitive member surface. The above setting method will be effective.

In the present invention, the free end of the elastic rubber blade is in the opposite direction (counter direction) to the rotation direction of the photoconductor.
It is preferable to press in contact.

The cleaning blade may be sprayed with a fluorine-based lubricant on the edge portion of the cleaning blade, if necessary, or the following fluorine-based polymer and fluorine-based polymer may be further applied to the tip portion extending over the entire width direction. It is preferable to apply a dispersion obtained by dispersing a resin powder in a fluorine-based solvent.

Next, the organic photoreceptor used in the present invention will be described. In the present invention, an organic electrophotographic photoreceptor (organic photoreceptor) is an electrophotography constituted by providing an organic compound with at least one of a charge generation function and a charge transport function essential for the configuration of the electrophotographic photoreceptor. Photoreceptor means all known organic electrophotographic photoreceptors such as a photoreceptor composed of a known organic charge generating substance or organic charge transporting substance, and a photoreceptor having a charge generating function and a charge transporting function composed of a polymer complex. contains.

Hereinafter, the constitution of the organic photoreceptor used in the present invention will be described. As the conductive support used for the photoreceptor of the present invention, either a sheet-like or a cylindrical support may be used, but a cylindrical conductive support is more preferable for designing a compact image forming apparatus.

The cylindrical conductive support used in the present invention means a cylindrical support necessary for forming an image endlessly by rotating, and has a straightness of 0.1 mm or less and a runout of 0.1 mm. Conductive supports in the following ranges are preferred. Exceeding the ranges of the roundness and the shake make it difficult to form a good image.

As the conductive material, a metal drum of aluminum, nickel, or the like, a plastic drum on which aluminum, tin oxide, indium oxide, or the like is deposited, or a paper or plastic drum coated with a conductive substance can be used. The conductive support preferably has a specific resistance of 10 ³ Ω · cm or less at room temperature.

The conductive support used in the present invention may have a surface on which a sealed alumite film is formed. The alumite treatment is usually performed in an acidic bath such as chromic acid, sulfuric acid, oxalic acid, phosphoric acid, boric acid, and sulfamic acid, but anodizing treatment in sulfuric acid gives the most preferable result. In the case of anodizing treatment in sulfuric acid, the sulfuric acid concentration is 100 to 200 g / l, the aluminum ion concentration is 1 to 10 g / l, and the liquid temperature is 20 ° C.
Before and after, the applied voltage is preferably about 20 V, but is not limited thereto. The average thickness of the anodic oxide film is usually 20 μm or less, particularly preferably 10 μm or less.

In the present invention, an intermediate layer having a barrier function can be provided between the conductive support and the photosensitive layer.

In the present invention, in order to improve the adhesiveness between the conductive support and the photosensitive layer or to prevent charge injection from the support, an intermediate layer (below the lower layer) is provided between the support and the photosensitive layer. (Including a subbing layer). Examples of the material for the intermediate layer include polyamide resins, vinyl chloride resins, vinyl acetate resins, and copolymer resins containing two or more of the repeating units of these resins. Among these resins, a polyamide resin is preferable as a resin capable of reducing an increase in residual potential due to repeated use. The thickness of the intermediate layer using these resins is preferably 0.01 to 0.5 μm.

The intermediate layer most preferably used in the present invention is an intermediate layer using a curable metal resin obtained by thermosetting an organic metal compound such as a silane coupling agent or a titanium coupling agent. The thickness of the intermediate layer using a curable metal resin is preferably 0.1 to 2 μm.

The photosensitive layer of the photoreceptor of the present invention may have a single-layer structure in which a charge generation function and a charge transport function are provided in one layer on the intermediate layer. Functions include charge generation layer (CGL) and charge transport layer (CT
It is preferable to adopt a configuration separated into L). By adopting a configuration in which functions are separated, an increase in residual potential due to repeated use can be controlled to be small, and other electrophotographic characteristics can be easily controlled according to the purpose. It is preferable that the photoreceptor for negative charging has a configuration in which a charge generation layer (CGL) is provided on the intermediate layer and a charge transport layer (CTL) is provided thereon. In the case of a positively charged photoreceptor, the order of the layer configuration is opposite to that of the negatively charged photoreceptor. The most preferred photosensitive layer structure of the present invention is a negatively charged photosensitive member having the function-separated structure.

The structure of the photosensitive layer of the function-separated negatively charged photosensitive member will be described below. In the charge generation layer, a charge generation material (CG
M). As other substances, a binder resin and other additives may be contained as necessary.

As the charge generating substance (CGM), a known charge generating substance (CGM) can be used. For example, phthalocyanine pigments, azo pigments, perylene pigments, azurenium pigments, and the like can be used. Among them, CGM that can minimize the increase in residual potential due to repeated use
Has a steric and potential structure capable of forming a stable aggregation structure among a plurality of molecules, and specifically includes CGM of a phthalocyanine pigment and a perylene pigment having a specific crystal structure. For example, Bragg angle 2θ for Cu-Kα ray
CGM such as titanyl phthalocyanine having a maximum peak at 27.2 ° and benzimidazole perylene having a maximum peak at 2θ of 12.4 have almost no deterioration due to repeated use, and the residual potential increase can be reduced.

When a binder is used as a dispersion medium of CGM in the charge generation layer, a known resin can be used as the binder, but the most preferable resin is a formal resin, a butyral resin, a silicone resin, a silicone-modified butyral resin, a phenoxy resin. Resins. The ratio between the binder resin and the charge generating substance is preferably from 20 to 600 parts by mass per 100 parts by mass of the binder resin. By using these resins, the increase in residual potential due to repeated use can be minimized. The thickness of the charge generation layer is preferably from 0.01 μm to 2 μm.

The charge transport layer contains a charge transport material (CTM) and a binder resin for dispersing the CTM and forming a film.
As other substances, additives such as antioxidants may be contained as necessary.

As the charge transport material (CTM), a known charge transport material can be used. For example, triphenylamine derivatives, hydrazone compounds, styryl compounds, benzidine compounds, butadiene compounds and the like can be used. These charge transport materials are usually dissolved in a suitable binder resin to form a layer. Among these, CTM that can minimize the increase in residual potential due to repeated use
Has high mobility and a difference in ionization potential from a combined CGM of 0.5 (eV) or less, and preferably 0.25 (eV) or less.

The ionization potential of CGM and CTM is measured with a surface analyzer AC-1 (manufactured by Riken Keiki Co., Ltd.).

Examples of the resin used for the charge transport layer (CTL) include polystyrene, acrylic resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, polyvinyl butyral resin, epoxy resin, polyurethane resin, phenol resin, polyester resin, and alkyd. Resin, polycarbonate resin, silicone resin, melamine resin,
Further, it is a copolymer resin containing two or more of the repeating units of these resins. In addition to these insulating resins, polymer organic semiconductors such as poly-N-vinyl carbazole may be used.

The most preferred binder for these CTLs is a polycarbonate resin having an average molecular weight of 40,000 or more. Polycarbonate resins are most preferred for improving the dispersibility and electrophotographic properties of CTM.
The ratio of the binder resin to the charge transporting material is preferably from 10 to 200 parts by mass per 100 parts by mass of the binder resin. The thickness of the charge transport layer is preferably from 10 to 40 μm.

Various resin layers can be provided as a protective layer of the photoreceptor used in the present invention. In particular, by providing a crosslinked resin layer, the organic photoreceptor of the present invention having high mechanical strength can be obtained.

It is preferable to use polycarbonate having an average molecular weight of 40,000 or more as a binder resin in the layer which is the outermost surface among the layers constituting the photosensitive member in order to improve durability.

The solvent or dispersion medium used for forming the intermediate layer, photosensitive layer, protective layer, etc. of the present invention includes n-butylamine, diethylamine, ethylenediamine, isopropanolamine, triethanolamine, triethylenediamine, N, N- Dimethylformamide, acetone, methyl ethyl ketone, methyl isopropyl ketone, cyclohexanone, benzene, toluene, xylene, chloroform, dichloromethane, 1,2-dichloroethane, 1,
2-dichloropropane, 1,1,2-trichloroethane, 1,1,1-trichloroethane, trichloroethylene, tetrachloroethane, tetrahydrofuran, dioxolan, dioxane, methanol, ethanol, butanol, isopropanol, ethyl acetate, butyl acetate, dimethyl sulfoxide, methyl Cellosolve and the like. Although the present invention is not limited to these, dichloromethane, 1,2-dichloroethane, methyl ethyl ketone and the like are preferably used. In addition, these solvents can be used alone or as a mixed solvent of two or more kinds.

Next, as a coating method for producing the organic electrophotographic photoreceptor of the present invention, coating methods such as dip coating, spray coating, and circular amount control type coating are used.
The coating process on the upper layer side of the photosensitive layer is performed by spray coating or by a circular amount control type (a typical example is a circular slide hopper type) in order to minimize dissolution of the lower layer film and achieve uniform coating. It is preferable to use It is most preferable that the protective layer of the present invention uses the above-mentioned circular amount control type coating method. The circular amount control type coating is described in detail in, for example, JP-A-58-189061.

Next, the toner used in the present invention will be described. The toner of the present invention is a toner for developing an electrostatic latent image obtained by forming toner particles in an aqueous medium,
This means that dispersed particles are formed in an aqueous medium and used as toner particles, and also include those formed by agglomerating and fusing some of the particles instead of the particles as they are.

Fine resin particles are prepared by suspension polymerization in an aqueous medium or emulsion polymerization or mini-emulsion polymerization of a monomer in an aqueous medium, and then a coagulant such as an organic solvent or a salt is prepared. The resin particles can be produced by a method of coagulating and fusing the resin particles. Further, a step of dissolving or dispersing a binder resin, a charge control agent, a colorant, and a release agent in an organic solvent for dissolving the binder resin to prepare an oily component, and dispersing the oily component in an aqueous medium. It can also be produced by a method for producing a toner for developing an electrostatic latent image having a step of granulating the toner from the state. Above all, monomers are emulsion-polymerized or mini-emulsion-polymerized in an aqueous medium to prepare fine resin particles, and thereafter, an organic solvent, a flocculant such as salts are added to coagulate and melt the resin particles. It is particularly preferable to use a method of attaching the toner, because toner shape control is relatively easy and stable cleaning properties can be obtained.

One example of a method for producing the toner of the present invention by the suspension polymerization method is as follows. A charge controlling resin is dissolved in a polymerizable monomer, and a colorant, a releasing agent if necessary, Add various constituent materials such as initiator, homogenizer,
Various constituent materials are dissolved or dispersed in the polymerizable monomer using a sand mill, a sand grinder, an ultrasonic disperser or the like. The polymerizable monomer in which these various constituent materials are dissolved or dispersed is dispersed in an aqueous medium containing a dispersion stabilizer into oil droplets of a desired size as a toner using a homomixer, a homogenizer, or the like. Thereafter, the mixture is transferred to a reaction device (stirring device) having two-stage stirring blades, and heated to progress the polymerization reaction. After the reaction, remove the dispersion stabilizer,
The toner of the present invention is prepared by filtration, washing, and drying. The “aqueous medium” in the present invention refers to a medium containing at least 50% by mass of water.

In the case of the emulsion polymerization method, a method for preparing the toner of the present invention by salting out, aggregating and fusing resin particles in an aqueous medium is preferably used. Can also be mentioned. Although this method is not particularly limited, for example, Japanese Patent Application Laid-Open No. 5-2652
52, JP-A-6-329947 and JP-A-9
-15904 can be mentioned.
That is, a method of salting out, aggregating, and fusing a plurality of fine particles composed of a resin and a colorant, or a dispersion particle of a constituent material such as a resin particle and a colorant, particularly dispersing these in water using an emulsifier. After that, a coagulant having a critical coagulation concentration or more is added and salted out, and at the same time, the formed polymer itself is heated and fused at a temperature of the glass transition temperature or more to gradually grow the particle size while forming fused particles. When the target particle size is reached, add a large amount of water to stop the particle size growth, further heat and stir to smooth the particle surface, control the shape, and heat the particles in a fluid state while keeping the particles wet. By drying, the toner of the present invention can be formed.
Here, a solvent such as alcohol which is infinitely soluble in water may be added together with the coagulant.

For the toner of the present invention, composite resin particles obtained by a multi-stage polymerization method can be used. It is preferable that a region other than the outermost layer of the composite resin particles contains a release agent.

The production process of the multi-stage polymerization toner mainly comprises the following processes. 1: Area where the release agent is other than the outermost layer (center or middle layer)
Multi-stage polymerization step (I) for obtaining composite resin particles contained in (2): salting-out / fusion step (II) in which the composite resin particles and colorant particles are subjected to salting-out / fusion to obtain toner particles : Filtering the toner particles from the dispersion system of the toner particles,
A filtration / washing step of removing a surfactant or the like from the toner particles; a drying step of drying the washed toner particles; and a step of adding an external additive to the dried toner particles.

Hereinafter, each step will be described in detail. Multi-stage polymerization step (I) The multi-stage polymerization step (I) is a step of producing composite resin particles by a multi-stage polymerization method in which a coating layer made of a monomer polymer is formed on the surface of the resin particles.

In the present invention, it is preferable to employ a multi-stage polymerization method of three-stage polymerization or more from the viewpoints of production stability and crushing strength of the obtained toner.

The two-stage polymerization method and the three-stage polymerization method, which are typical examples of the multi-stage polymerization method, will be described below.

Two-stage polymerization method A two-stage polymerization method is a composite comprising a central portion (core) formed of a high molecular weight resin containing a release agent and an outer layer (shell) formed of a low molecular weight resin. This is a method for producing resin particles.

More specifically, this method will be described. First, a release agent is dissolved in a monomer to prepare a monomer solution, and this monomer solution is placed in an aqueous medium (for example, an aqueous surfactant solution). After the oil droplets are dispersed, the system is subjected to a polymerization treatment (first-stage polymerization) to prepare a dispersion of high-molecular-weight resin particles containing a release agent.

Next, a polymerization initiator and a monomer for obtaining a low molecular weight resin are added to the dispersion of the resin particles, and the monomer is subjected to a polymerization treatment in the presence of the resin particles (second stage polymerization). Is carried out to form a coating layer made of a low-molecular-weight resin (a polymer of a monomer used later) on the surface of the resin particles.

Three-stage polymerization method The three-stage polymerization method comprises a central part (nucleus) formed from a high molecular weight resin, an intermediate layer containing a release agent, and an outer layer (shell) formed from a low molecular weight resin. This is a method for producing composite resin particles.

The method will be described in detail. First, a dispersion of resin particles obtained by a polymerization treatment (first-stage polymerization) according to a conventional method is added to an aqueous medium (for example, an aqueous solution of a surfactant). Along with the addition, the monomer solution obtained by dissolving the release agent in the monomer is dispersed in oil droplets in the aqueous medium, and then the system is subjected to a polymerization treatment (second-stage polymerization).
On the surface of the resin particles (core particles), a coating layer (intermediate layer) made of a resin containing a release agent (a polymer of the monomer used in the second step) is formed, and composite resin particles (high molecular weight A resin-intermediate molecular weight resin) dispersed liquid is prepared.

Next, a polymerization initiator and a monomer for obtaining a low-molecular-weight resin are added to the resulting dispersion of the composite resin particles, and the monomer is subjected to a polymerization treatment in the presence of the composite resin particles (the By performing the three-stage polymerization, a coating layer made of a low-molecular-weight resin (a polymer of a monomer used last) is formed on the surface of the composite resin particles. In the above method, by incorporating the second-stage polymerization, the release agent can be finely and uniformly dispersed, which is preferable.

One feature of the method for producing a toner according to the present invention is to polymerize a polymerizable monomer in an aqueous medium. That is, when forming resin particles (core particles) or a coating layer (intermediate layer) containing a release agent, the release agent is dissolved in a monomer, and the resulting monomer solution is oiled in an aqueous medium. In this method, latex particles are obtained by dispersing droplets, adding a polymerization initiator to the system, and performing a polymerization treatment.

The aqueous medium referred to in the present invention is water 50 to 10
A medium comprising 0% by mass and 0 to 50% by mass of a water-soluble organic solvent. Examples of the water-soluble organic solvent include, for example, methanol, ethanol, isopropanol, butanol,
Acetone, methyl ethyl ketone, tetrahydrofuran and the like can be exemplified, and an alcohol-based organic solvent which does not dissolve the obtained resin is preferable.

Suitable polymerization methods for forming resin particles (core particles) containing a release agent or a coating layer thereof include:
A monomer solution in which a release agent is dissolved in a monomer is dissolved in an aqueous medium in which a surfactant having a concentration equal to or lower than the critical micelle concentration is dissolved, and oil droplets are dispersed using mechanical energy to obtain a dispersion. Is prepared, a water-soluble polymerization initiator is added to the obtained dispersion, and radical polymerization is performed in oil droplets (hereinafter, referred to as “mini-emulsion method” in the present invention). The effect can be more exhibited, which is preferable.
In the above method, instead of the water-soluble polymerization initiator,
Alternatively, an oil-soluble polymerization initiator may be used together with the water-soluble polymerization initiator.

According to the miniemulsion method in which oil droplets are formed mechanically, unlike a normal emulsion polymerization method, the release agent dissolved in the oil phase does not detach, and the resin particles ( A sufficient amount of release agent can be introduced into the core particle) or its coating layer.

Here, the disperser for dispersing oil droplets by mechanical energy is not particularly limited. For example, a stirrer “CLEARMIX” (M -Technic), ultrasonic disperser, mechanical homogenizer,
Mentongorin and a pressure-type homogenizer can be used. In addition, the dispersion particle diameter is 10 to
1000 nm, preferably 50 to 1000 nm,
More preferably, it is 30 to 300 nm.

In addition, as another polymerization method for forming resin particles or a coating layer containing a release agent, an emulsion polymerization method,
Known methods such as a suspension polymerization method and a seed polymerization method can also be employed. These polymerization methods can also be employed to obtain resin particles (core particles) constituting the composite resin particles or a coating layer thereof, which does not contain a release agent.

The particle diameter of the composite resin particles obtained in the polymerization step (I) is determined by an electrophoretic light scattering photometer “ELS-80”.
It is preferable that the weight average particle diameter measured using “0” (manufactured by Otsuka Electronics Co., Ltd.) is in the range of 10 to 1000 nm.

Further, the glass transition temperature (T
g) is preferably in the range of 48 to 74 ° C, more preferably 52 to 64 ° C.

The softening point of the composite resin particles is 95-14.
It is preferably in the range of 0 ° C. Salting-out / fusion step (II) The salting-out / fusion step (II) is carried out in the multi-stage polymerization step (I).
Salting out the composite resin particles and the colorant particles obtained by
This is a step of obtaining amorphous (non-spherical) toner particles by fusing (simultaneously salting out and fusing).

The salting out / fusion in the present invention means that salting out (aggregation of particles) and fusion (loss of interface between particles) occur simultaneously, or salting out and fusion occur simultaneously. Act. In order to simultaneously carry out the salting-out and the fusion, the particles (composite resin particles, colorant particles) under a temperature condition not lower than the glass transition temperature (Tg) of the resin constituting the composite resin particles.
Need to be aggregated.

In this salting-out / fusion step (II), together with the composite resin particles and the colorant particles, internal additive particles such as a charge control agent (fine particles having a number average primary particle diameter of about 10 to 1000 nm) are salted out. / It may be fused. The colorant particles may be surface-modified, and as the surface modifier,
Conventionally known ones can be used.

The colorant particles are subjected to salting-out / fusion treatment in a state of being dispersed in an aqueous medium. The aqueous medium in which the colorant particles are dispersed is preferably an aqueous solution in which a surfactant is dissolved at a concentration equal to or higher than the critical micelle concentration (CMC).

The disperser used for the dispersion treatment of the colorant particles is not particularly limited, but is preferably a stirrer “CLEARMIX (CLEARM) equipped with a high-speed rotating rotor.
MIX) "(manufactured by M-Technic), ultrasonic disperser,
Examples include a pressure disperser such as a mechanical homogenizer, a Manton-Gaulin, a pressure homogenizer, and a medium disperser such as a Getzman mill or a diamond fine mill.

In order to salt out / fuse the composite resin particles and the colorant particles, a salting-out agent (coagulant having a critical aggregation concentration or higher) is added to the dispersion in which the composite resin particles and the colorant particles are dispersed. ) And heating the dispersion above the glass transition temperature (Tg) of the composite resin particles.

The preferable temperature range for salting out / fusing is (Tg + 10 ° C.) to (Tg + 50 ° C.)
It is particularly preferably (Tg + 15 ° C.) to (Tg + 40 ° C.). Further, in order to effectively perform the fusion, an organic solvent which is infinitely soluble in water may be added.

Filtration / Washing Step In this filtration / washing step, a filtration treatment for filtering the toner particles from the dispersion system of the toner particles obtained in the above step, a filtration treatment for the toner particles (a cake-like aggregate) are performed. ) Is subjected to a washing treatment for removing deposits such as surfactants and salting-out agents.

Here, the filtration method is not particularly limited, such as a centrifugal separation method, a reduced pressure filtration method using a Nutsche method, and a filtration method using a filter press or the like.

Drying Step This step is a step of drying the washed toner particles.

[0115] Examples of the dryer used in this step include a spray dryer, a vacuum freeze dryer, and a reduced-pressure dryer. A stationary shelf dryer, a movable shelf dryer, a fluidized bed dryer, a rotary bed dryer, and the like. It is preferable to use a type dryer, a stirring type dryer and the like.

The water content of the dried toner particles is preferably 5% by mass or less, more preferably 2% by mass or less.

Incidentally, the dried toner particles are
In the case where the aggregates are aggregated by a weak attraction between particles, the aggregates may be crushed. Here, as the crushing device,
A mechanical crusher such as a jet mill, a Henschel mixer, a coffee mill, and a food processor can be used.

The toner particles (colored particles) of the present invention were salted out /
Although there is no particular limitation on the preparation by fusing, the composite resin particles are formed in the absence of a colorant, and the dispersion of the colorant particles is added to the dispersion of the composite resin particles. It is preferably prepared by salting out / fusing the particles with the colorant particles.

As described above, by preparing the composite resin particles in a system in which no colorant is present, the polymerization reaction for obtaining the composite resin particles is not hindered. Therefore, according to the toner of the present invention, the excellent offset resistance is not impaired, and the fixing device is not stained or the image is not stained due to the accumulation of the toner.

Further, as a result of reliably performing the polymerization reaction for obtaining the composite resin particles, no monomer or oligomer remains in the obtained toner particles. No unpleasant odor is generated in the heat fixing step.

Further, the surface characteristics of the obtained toner particles are uniform and the charge amount distribution is sharp, so that an image having excellent sharpness can be formed for a long period of time. According to such a toner having a uniform composition, molecular weight, and surface characteristics among toner particles, good adhesion (high fixing strength) to an image support is maintained in an image forming method including a fixing step by a contact heating method. Meanwhile, the offset resistance and the anti-winding property can be improved, and an image having an appropriate gloss can be obtained.

Next, each constituent material / element used in the toner manufacturing process will be described in detail.

(Polymerizable Monomer) As a polymerizable monomer for producing the resin (binder) used in the present invention, a hydrophobic monomer is an essential component, and if necessary, a crosslinkable monomer is used. A dimer is used. As described below, it is desirable to contain at least one monomer having an acidic polar group or a monomer having a basic polar group.

(1) Hydrophobic monomer The hydrophobic monomer constituting the monomer component is not particularly limited, and a conventionally known monomer can be used. In addition, one kind or a combination of two or more kinds can be used so as to satisfy required characteristics.

Specifically, monovinyl aromatic monomers,
It is possible to use (meth) acrylate monomers, vinyl ester monomers, vinyl ether monomers, monoolefin monomers, diolefin monomers, halogenated olefin monomers, and the like. it can.

Examples of the vinyl aromatic monomer include styrene, o-methylstyrene, m-methylstyrene and p-methylstyrene.
-Methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, p-ethylstyrene, p-n-butylstyrene, p-tert-butylstyrene, p-n-hexylstyrene, p-n-octyl Styrene monomers such as styrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, 2,4-dimethylstyrene, and 3,4-dichlorostyrene, and derivatives thereof.

Examples of the acrylic monomer include acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate,
Methyl methacrylate, ethyl methacrylate, butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, β-hydroxyethyl acrylate, γ-
Propyl aminoacrylate, stearyl methacrylate,
Examples thereof include dimethylaminoethyl methacrylate and diethylaminoethyl methacrylate.

Examples of the vinyl ester monomers include vinyl acetate, vinyl propionate, vinyl benzoate and the like.

Examples of the vinyl ether monomer include vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, vinyl phenyl ether and the like.

Examples of the monoolefin-based monomer include ethylene, propylene, isobutylene, 1-butene, 1-pentene, 4-methyl-1-pentene and the like.

Examples of the diolefin-based monomer include butadiene, isoprene, chloroprene and the like.

(2) Crosslinkable monomer A crosslinkable monomer may be added to improve the properties of the resin particles. Examples of the crosslinkable monomer include those having two or more unsaturated bonds such as divinylbenzene, divinylnaphthalene, divinyl ether, diethylene glycol methacrylate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, and diallyl phthalate.

(3) Monomer having an acidic polar group Examples of the monomer having an acidic polar group include (a) an α, β-ethylenically unsaturated compound having a carboxyl group (—COOH) and (b) a sulfone. Α, β-ethylenically unsaturated compounds having a group (—SO ₃ H) can be mentioned.

Examples of the α, β-ethylenically unsaturated compound having a —COOH group of (a) include acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid, cinnamic acid, and monobutyl maleate. Examples thereof include esters, monooctyl maleate, and metal salts of Na, Zn and the like.

Examples of the (b) α, β-ethylenically unsaturated compound having a —SO ₃ H group include sulfonated styrene, its Na salt, allyl sulfosuccinic acid, allyl sulfosuccinate octyl, its Na salt and the like. be able to.

(4) Monomer having a basic polar group Examples of the monomer having a basic polar group include (i) an amine group or a quaternary ammonium group having 1 to 1 carbon atoms.
2, preferably 2 to 8, particularly preferably 2, (meth) acrylic esters of aliphatic alcohols, (ii) (meth)
Acrylamide or optionally N-C18
(Meth) acrylic acid amide mono- or di-substituted with an alkyl group, (iii) a vinyl compound substituted with a heterocyclic group having N as a ring member, and (iv) N, N-diallyl-
Examples thereof include an alkylamine and a quaternary ammonium salt thereof. Among them, (i) the (meth) acrylic acid ester of an aliphatic alcohol having an amine group or a quaternary ammonium group is preferable as the monomer having a basic polar group.

Examples of the (meth) acrylate of an aliphatic alcohol having an amine group or a quaternary ammonium group (i) include dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate, diethylaminoethyl methacrylate, Quaternary ammonium salts of four compounds, 3-dimethylaminophenyl acrylate, 2-hydroxy-
Examples thereof include 3-methacryloxypropyltrimethylammonium salt.

Examples of (ii) (meth) acrylamide or (meth) acrylamide optionally mono- or dialkyl-substituted on N include acrylamide, N-butylacrylamide, N, N-dibutylacrylamide, piperidylacrylamide, Methacrylamide, N-butyl methacrylamide, N, N-dimethylacrylamide,
N-octadecylacrylamide and the like can be mentioned.

Examples of the vinyl compound (iii) substituted by a heterocyclic group having N as a ring member include vinyl pyridine,
Vinyl pyrrolidone, vinyl-N-methylpyridinium chloride, vinyl-N-ethylpyridinium chloride and the like can be mentioned.

Examples of (iv) N, N-diallyl-alkylamine include N, N-diallylmethylammonium chloride, N, N-diallylethylammonium chloride and the like.

(Polymerization Initiator) The radical polymerization initiator used in the present invention can be appropriately used as long as it is water-soluble. For example, persulfates (eg, potassium persulfate, ammonium persulfate, etc.), azo compounds (eg, 4,4 ′)
-Azobis-4-cyanovaleric acid and salts thereof, 2,2'-azobis (2-amidinopropane) salts and the like), peroxide compounds and the like. Further, the above radical polymerization initiator can be used as a redox initiator in combination with a reducing agent, if necessary. The use of a redox initiator is preferable because the polymerization activity is increased, the polymerization temperature can be reduced, and the polymerization time can be further shortened.

As the polymerization temperature, any temperature may be selected as long as it is equal to or higher than the lowest radical generation temperature of the polymerization initiator. However, by using a polymerization initiator started at room temperature, for example, a combination of hydrogen peroxide and a reducing agent (such as ascorbic acid), polymerization can be performed at room temperature or higher.

(Chain Transfer Agent) For the purpose of adjusting the molecular weight, a known chain transfer agent can be used. The chain transfer agent is not particularly limited, for example, octyl mercaptan, dodecyl mercaptan,
A compound having a mercapto group such as tert-dodecyl mercaptan is used. In particular, a compound having a mercapto group is preferably used because it suppresses odor at the time of heating and fixing, and a toner having a sharp molecular weight distribution is obtained, and has excellent storage stability, fixing strength, and offset resistance. For example, ethyl thioglycolate, propyl thioglycolate, propyl thioglycolate, butyl thioglycolate, t-butyl thioglycolate, 2-ethylhexyl thioglycolate, octyl thioglycolate, decyl thioglycolate, dodecyl thioglycolate And compounds having a mercapto group of ethylene glycol, compounds having a mercapto group of neopentyl glycol, and compounds having a mercapto group of pentaerythritol. Among them, n-octyl-3-mercaptopropionate is particularly preferable from the viewpoint of suppressing odor during toner heat fixing.

(Surfactant) In order to carry out the miniemulsion polymerization using the above-mentioned polymerizable monomer, it is preferable to disperse oil droplets in an aqueous medium using a surfactant. Surfactants that can be used at this time are not particularly limited, but the following ionic surfactants can be mentioned as examples of suitable compounds.

Examples of the ionic surfactant include sulfonates (sodium dodecylbenzenesulfonate,
Sodium arylalkyl polyether sulfonate,
3,3-disulfonediphenylurea-4,4-diazo-
Sodium bis-amino-8-naphthol-6-sulfonate, ortho-carboxybenzene-azo-dimethylaniline, 2,2,5,5-tetramethyl-triphenylmethane-4,4-diazo-bis-β-naphthol -6
Sodium sulfonate), sulfate salts (sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, etc.),
Fatty acid salts (sodium oleate, sodium laurate, sodium caprate, sodium caprylate, sodium caproate, potassium stearate, calcium oleate, etc.) are exemplified.

Further, nonionic surfactants can also be used. Specifically, for example, polyethylene oxide, polypropylene oxide, a combination of polypropylene oxide and polyethylene oxide, esters of polyethylene glycol and higher fatty acids, alkylphenol polyethylene oxide, esters of higher fatty acids and polyethylene glycol, esters of higher fatty acids and polypropylene oxide, And sorbitan esters.

In the present invention, these surfactants are mainly used as an emulsifier at the time of emulsion polymerization, but may be used for other steps or other purposes.

(Molecular Weight Distribution of Resin Particles and Toner) The toner of the present invention has a peak or shoulder of 100,000 to 1,0.
Preferably, the peak or shoulder is 100,000, and between 1,000 and 50,000.
000-1,000,000, 25,000-150,
More preferably it is present between 000 and 1,000 to 50,000.

The molecular weight of the resin particles is from 100,000 to
A resin containing at least a high molecular weight component having a peak or shoulder in the region of 1,000,000 and a low molecular weight component having a peak or shoulder in the region of 1,000 to less than 50,000 is preferred. More preferably, it is preferable to use an intermediate molecular weight resin having a peak or shoulder at a peak molecular weight of 15,000 to 100,000.

The method for measuring the molecular weight of toner or resin is as follows.
The measurement is preferably performed by GPC (gel permeation chromatography) using THF (tetrahydrofuran) as a solvent. That is, 1.0 ml of THF is added to 0.5 to 5 mg, more specifically, 1 mg of a measurement sample, and the mixture is stirred at room temperature using a magnetic stirrer or the like to be sufficiently dissolved. Then, pore size 0.45 to 0.50
After treating with a μm membrane filter, the mixture is injected into GPC. The GPC measurement conditions were as follows: the column was stabilized at 40 ° C., THF was flowed at a flow rate of 1.0 ml per minute, and 1 m
Approximately 100 μl of a sample at a concentration of g / ml is injected and measured. The column is preferably used in combination with a commercially available polystyrene gel column. For example, Shodex KF-801, 802, 803, 8 manufactured by Showa Denko KK
04, 805, 806, and 807, and TSKgel G1000H, G2000H, and G30 manufactured by Tosoh Corporation.
00H, G4000H, G5000H, G6000H,
G7000H, a combination of TSK guard column and the like. Also, as a detector,
It is preferable to use a refractive index detector (IR detector) or a UV detector. In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated using a calibration curve created using monodispersed polystyrene standard particles. It is preferable to use about 10 polystyrenes for preparing a calibration curve.

(Flocculant) The flocculant used in the present invention is:
Those selected from metal salts are preferred.

Examples of the metal salt include salts of monovalent metals such as alkali metals such as sodium, potassium and lithium, salts of divalent metals such as alkaline earth metals such as calcium and magnesium, and salts of manganese and copper. Valent metal salts, iron,
Examples thereof include trivalent metal salts such as aluminum.

Specific examples of these metal salts are shown below.
Specific examples of metal salts of monovalent metals include sodium chloride,
Potassium chloride, lithium chloride, and metal salts of divalent metals include calcium chloride, zinc chloride, copper sulfate, magnesium sulfate, and manganese sulfate. Examples of the trivalent metal salt include aluminum chloride and iron chloride. These are appropriately selected according to the purpose. In general, the divalent metal salt has a smaller critical aggregation concentration (coagulation value or coagulation point) than the monovalent metal salt, and the trivalent metal salt has a smaller critical aggregation concentration.

The critical aggregation concentration referred to in the present invention is an index relating to the stability of a dispersion in an aqueous dispersion, and indicates the concentration at which aggregation occurs when an aggregating agent is added. This critical aggregation concentration varies greatly depending on the latex itself and the dispersant. For example, Seizo Okamura et al., Polymer Chemistry 17,601
(1960), and according to these descriptions, the value can be known. Also, as another method,
It is also possible to add a desired salt to the target particle dispersion at a different concentration, measure the ζ potential of the dispersion, and determine the salt concentration at the point where the ζ potential changes to be the critical aggregation concentration.

In the present invention, the polymer fine particle dispersion is treated with a metal salt so as to have a concentration equal to or higher than the critical aggregation concentration. At this time, of course, whether to add the metal salt directly or as an aqueous solution is arbitrarily selected depending on the purpose. In the case of adding as an aqueous solution, the added metal salt needs to be at or above the critical aggregation concentration of the polymer particles with respect to the volume of the polymer particle dispersion and the total volume of the metal salt aqueous solution.

The concentration of the metal salt as the coagulant in the present invention may be at least the critical coagulation concentration, but is preferably added at least 1.2 times, more preferably at least 1.5 times the critical coagulation concentration.

Next, the steps of dissolving or dispersing the raw materials of the binder resin, the colorant, and the wax in an organic solvent to form an oil phase component and the method of granulating the oil phase component in an aqueous medium are described. 1 shows an example of a preferred production method of the present invention.

A step of dissolving or dispersing the binder resin, the charge control agent, the coloring agent, and the releasing agent in an organic solvent for dissolving the binder resin to prepare an oily component; and dispersing the oily component in an aqueous medium. And a step of granulating the toner from the state in which the toner is developed.

The step of dissolving and dispersing a binder resin, a colorant, and a wax in an organic solvent for solubilizing the binder resin to prepare an oily component includes:
This is a step of mixing and dispersing the charge control resin, the colorant, and the release agent in an organic solvent that solubilizes the binder resin.

As an organic solvent for solubilizing the binder resin, a general organic solvent is used. For example, toluene, xylene, hydrocarbons such as hexane, methylene chloride,
Chloroform, halogenated hydrocarbons such as dichloroethane, alcohols such as methanol and ethanol, ethers such as tetrahydrofuran, methyl acetate, ethyl acetate,
Esters such as butyl acetate, acetone, methyl ethyl ketone, ketones such as cyclohexanone, and the like,
Among them, ethyl acetate, methyl ethyl ketone, and the like are preferable from the viewpoint of the solubility of the resin and the solvent removing property. These may be used alone or as a mixture.

The step of granulating the toner from a state in which the oily component is dispersed in the aqueous medium means that the oily component adjusted in the above step is solidified from the state in which the oily component is dispersed in the aqueous medium to produce particles. This is a step of drying to obtain a toner.

As a method for producing particles, a solution obtained by dissolving and dispersing the binder resin, the charge control agent, the colorant, the release agent, and other materials in a solvent is suspended and dispersed in an aqueous medium. Thereafter, a method of removing the solvent, a method of precipitating particles by adding an aqueous poor solvent to the solution, a binder resin, a charge control agent, a coloring agent, a release agent,
A method in which a heated melt containing other materials is melt-dispersed in an aqueous medium and then cooled to form particles, and the like.

As the aqueous medium, water is mainly used, but a water-soluble solvent may be mixed. Further, it is preferable to add a dispersant in terms of particle size distribution. As dispersants, tricalcium phosphate, hydroxyapatite, calcium carbonate, titanium oxide, aluminum hydroxide, magnesium hydroxide, barium sulfate, silica, cellulose,
Examples include hydroxypropylmethylcellulose, methylcellulose, carboxymethylcellulose, starch, polyvinyl alcohol, polyacrylic acid, and the like. The amount of the dispersant is preferably 0 to 20 parts by mass with respect to 100 parts by mass of the mother liquor.

As a stirring method for producing particles, it is desirable to apply shearing, and a homogenizer, a colloid mill, a dissolver, or the like is used.

For drying, a through-air drying device, a spray drying device,
A rotary drier, a flash drier, a fluidized bed drier, a heat transfer type drier, a freeze drier, and the like are known, and any of them can be used.

Examples of the colorant constituting the toner of the present invention include various inorganic pigments, organic pigments, and dyes. Conventionally known inorganic pigments can be used. Specific inorganic pigments are exemplified below.

Examples of black pigments include furnace black, channel black, acetylene black,
Carbon black such as thermal black and lamp black, and magnetic powder such as magnetite and ferrite are also used.

These inorganic pigments can be used alone or in combination of two or more as desired. The amount of the pigment to be added is 2 to 20% by mass, preferably 3 to 15% by mass, based on the polymer.

When used as a magnetic toner, the above-mentioned magnetite can be added. In this case, from the viewpoint of imparting predetermined magnetic characteristics, 20 to 6
It is preferable to add 0% by mass.

Conventionally known organic pigments and dyes can also be used. Specific examples of organic pigments and dyes are shown below.

The pigments for magenta or red include:
For example, C.I. I. Pigment Red 2, C.I. I. Pigment Red 3, C.I. I. Pigment Red 5, C.I. I.
Pigment Red 6, C.I. I. Pigment Red 7,
C. I. Pigment Red 15, C.I. I. Pigment Red 16, C.I. I. Pigment Red 48: 1, C.I.
I. Pigment Red 53: 1, C.I. I. Pigment Red 57: 1, C.I. I. Pigment Red 122, C.I.
I. Pigment Red 123, C.I. I. Pigment Red 139, C.I. I. Pigment red 144, C.I. I.
Pigment Red 149, C.I. I. Pigment Red 1
66, C.I. I. Pigment Red 177, C.I. I. Pigment Red 178, C.I. I. Pigment Red 222
And the like.

Examples of orange or yellow pigments include C.I. I. Pigment Orange 31, C.I.
I. Pigment Orange 43, C.I. I. Pigment Yellow 12, C.I. I. Pigment Yellow 13, C.I. I.
Pigment Yellow 14, C.I. I. Pigment Yellow 15, C.I. I. Pigment Yellow 17, C.I. I. Pigment Yellow 93, C.I. I. Pigment Yellow 9
4, C.I. I. Pigment yellow 138, C.I. I. Pigment yellow 180, C.I. I. Pigment Yellow 1
85, C.I. I. Pigment yellow 155, C.I. I. Pigment Yellow 156 and the like.

Examples of green or cyan pigments include:
For example, C.I. I. Pigment Blue 15, C.I. I. Pigment Blue 15: 2, C.I. I. Pigment Blue 1
5: 3, C.I. I. Pigment Blue 16, C.I. I. Pigment Blue 60, C.I. I. Pigment Green 7 and the like.

As the dye, for example, C.I. I. Solvent Red 1, 49, 52, 58, 63
111, 122, C.I. I. Solvent Yellow 1
9, 44, 77, 79, 81, 82, 9
3, 98, 103, 104, 112, 16
2, C.I. I. Solvent Blue 25, 36, 60
70, 93, 95, etc., and mixtures thereof can also be used.

These organic pigments and dyes can be used alone or in combination as required.
The amount of the pigment added is 2 to 20% by mass based on the polymer.
And preferably 3 to 15% by mass.

The colorant (colorant particles) constituting the toner of the present invention may be surface-modified. As the surface modifier, a conventionally known one can be used, and specifically, a silane coupling agent, a titanium coupling agent, an aluminum coupling agent and the like can be preferably used. Examples of the silane coupling agent include alkoxysilanes such as methyltrimethoxysilane, phenyltrimethoxysilane, methylphenyldimethoxysilane, and diphenyldimethoxysilane, siloxanes such as hexamethyldisiloxane, γ-chloropropyltrimethoxysilane, and vinyltrimethoxysilane. Chlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane,
γ-ureidopropyltriethoxysilane and the like. As the titanium coupling agent, for example, TTS, 9S, 38S, 41B, 46B, 55, 138, which are commercially available under the trade name of “Preneact” manufactured by Ajinomoto Co., Inc.
S-1, 238S, etc., commercial products A-1 and B- manufactured by Nippon Soda Co., Ltd.
1, TOT, TST, TAA, TAT, TLA, TO
G, TBSTA, A-10, TBT, B-2, B-4,
B-7, B-10, TBSTA-400, TTS, TO
A-30, TSDMA, TTAB, TTOP and the like. As the aluminum coupling agent, for example,
"Plenact AL-M" manufactured by Ajinomoto Co. and the like.

The addition amount of these surface modifiers is preferably from 0.01 to 20% by mass, more preferably from 0.1 to 5% by mass, based on the colorant.

Examples of the method for modifying the surface of the colorant particles include a method in which a surface modifier is added to a dispersion of the colorant particles, and the system is heated and reacted.

[0179] The surface-modified colorant particles are collected by filtration, and are subjected to drying after repeated washing and filtering with the same solvent.

The toner used in the present invention is preferably a toner obtained by fusing resin particles containing a release agent in an aqueous medium. In this manner, the resin particles having the release agent encapsulated in the resin particles are salted out with the colorant particles in an aqueous medium.
By fusing, a toner in which a release agent is finely dispersed can be obtained.

In the toner of the present invention, a low molecular weight polypropylene (number average molecular weight = 1500 to 900) is used as a release agent.
0), low molecular weight polyethylene, and the like are preferable, and an ester compound represented by the following formula is particularly preferable.

R _1- (OCO-R ₂ ) _{n In the} formula, n is an integer of 1 to 4, preferably 2 to 4, more preferably 3 to 4, and particularly preferably 4. R _1, R
₂ represents a hydrocarbon group which may have a substituent. R ₁
Has 1 to 40 carbon atoms, preferably 1 to 20 carbon atoms, and more preferably 2 to 5 carbon atoms. R ₂ has 1 to 40 carbon atoms, preferably 16 to 30 carbon atoms, and more preferably 18 to 26 carbon atoms.

Next, examples of typical compounds are shown below.

[0184]

Embedded image

[0185]

Embedded image

The addition amount of the above compound is 1 to 30% by mass, preferably 2 to 20% by mass, and more preferably 3 to 15% by mass based on the whole toner.

In the present invention, the “crush strength index” is an index indicating the crushability of toner particles.
Specifically, it refers to an index determined by the following method.

(Method) 30 g of a toner (sample) and 100 g of glass beads “GB503M” (manufactured by Toshiba Barotini Co., particle size: 2 mm) were placed in a 2 liter polyethylene pot, and mixed and stirred for 60 seconds with a turbular mixer. Separate and remove the glass beads with a 330 mesh test sieve.

Before and after the mixing and stirring, the number ratio (%) of small particles of 2 to 4 μm in all the toner particles is measured and calculated by the following equation.

Crushing strength index = (N−N ₀ ) / 60 (where N is the number% of small particles of 2 to 4 μm after mixing and stirring, and N ₀ is 2 to 4 μm before mixing and stirring).
m is the number% of small particles. Note that the “number% of small particles” is a value measured using a Coulter Multisizer. Specifically, an interface (manufactured by Nikkaki) for outputting a particle size distribution and a personal computer are used by using a Coulter Multisizer. The aperture in the Coulter Multisizer was 100 μm, and 2
It was calculated by measuring the volume distribution of toner having a size of at least μm (for example, 2 to 40 μm).

The toner according to the sixteenth aspect of the present invention is a toner containing a resin, a release agent and a colorant, and is characterized in that the crushing strength index as defined above is 0.1 to 0.8. Have.

The toner having a crushing strength index of more than 0.8 is
If the toner cannot be sufficiently crushed and is subjected to image formation for a long period of time, fine powder generated by the crushing causes filming, fogging, carrier spent, and the like.

On the other hand, toners having a crushing strength index of less than 0.1 tend to have a high minimum fixing temperature, and cannot sufficiently meet the demands for downsizing and low power consumption of copying machines.

The toner of the present invention is preferably prepared by encapsulating the above-mentioned release agent in resin particles by miniemulsion polymerization, salting out and fusing with the colored particles.

The toner of the present invention can be used by adding a so-called external additive for the purpose of improving fluidity and cleaning property. These external additives are not particularly limited, and various inorganic fine particles, organic fine particles, and lubricants can be used.

As the inorganic fine particles that can be used as an external additive, conventionally known inorganic fine particles can be exemplified. Specifically, silica fine particles, titanium fine particles, alumina fine particles and the like can be preferably used. These inorganic fine particles are preferably hydrophobic.

Specific examples of the silica fine particles include commercial products R-805, R-976, and R-97 manufactured by Nippon Aerosil Co., Ltd.
4, R-972, R-812, R-809, HVK-2150, H-200 manufactured by Hoechst, and commercial products TS-720, TS-530, TS-610, H manufactured by Cabot
-5, MS-5 and the like.

Specific examples of the titanium fine particles include, for example,
Commercial products T-805 and T-604 manufactured by Nippon Aerosil Co., Ltd.
Commercial products MT-100S and MT-100B manufactured by Teika Co., Ltd.
MT-500BS, MT-600, MT-600SS,
JA-1, commercially available TA-300SI manufactured by Fuji Titanium Co.,
TA-500, TAF-130, TAF-510, TA
F-510T, Idemitsu Kosan's commercial products IT-S, IT-
OA, IT-OB, IT-OC and the like.

Specific examples of the alumina fine particles include, for example, commercial products RFY-C and C-60 manufactured by Nippon Aerosil Co., Ltd.
4, commercially available TTO-55 manufactured by Ishihara Sangyo Co., Ltd., and the like.

Examples of the organic fine particles that can be used as an external additive include spherical fine particles having a number average primary particle diameter of about 10 to 2000 nm. Examples of the constituent material of the organic fine particles include polystyrene, polymethyl methacrylate, and styrene-methyl methacrylate copolymer.

The amount of the external additive is preferably about 0.1 to 5% by mass based on the toner.

Examples of the apparatus used for adding the external additive include a turbulent mixer, a Hensiel mixer,
Various known mixing devices such as a Nauta mixer and a V-type mixer can be used.

The particle diameter of the toner of the present invention is preferably 2 to 10 μm, more preferably 3 to 10 μm in number average particle diameter.
８8 μm. This particle size can be controlled by the concentration of the coagulant (salting agent), the amount of the organic solvent added, the fusing time, and the composition of the polymer in the method for producing the toner.

When the number average particle diameter is 2 to 10 μm, in the fixing step, toner particles having a large adhesive force which fly and adhere to the heating member to generate offset are reduced, and the transfer efficiency is increased. The halftone image quality is improved, and the image quality of fine lines and dots is improved.

The number average particle diameter of the toner is determined by using Coulter Counter TA-II, Coulter Multisizer, SLAD
It can be measured using 1100 (manufactured by Shimadzu Corporation: laser diffraction particle size analyzer) or the like.

In the present invention, a Coulter Multisizer was used, and an interface for outputting a particle size distribution (manufactured by Nikkaki Co., Ltd.) and a personal computer were connected. The particle size distribution and the average particle size were calculated by measuring the volume distribution of toner having a size of 2 μm or more (for example, 2 to 40 μm) using an aperture of 100 μm as the aperture in the Coulter Multisizer.

The shape factor of the toner of the present invention is represented by the following equation, and indicates the degree of roundness of the toner particles.

Shape coefficient = ((maximum diameter / 2) ² × π) / projected area Here, the maximum diameter is defined as a parallel line when a projected image of a toner particle on a plane is sandwiched between two parallel lines. Means the width of the particle at which the distance between the particles becomes maximum. The projection area refers to the area of the projected image of the toner particles on the plane. In the present invention, the shape factor can be determined by taking a photograph in which the toner particles are magnified 2,000 times with a scanning electron microscope, and then referring to the “SCCANNING IMAGE ANALYZE” based on the photograph.
R "(manufactured by JEOL Ltd.) was used to analyze photographic images. In this case, the shape factor of the present invention was measured by using the above formula using 100 toner particles.

It is desirable that the proportion of toner particles having a shape factor in the range of 1.0 to 1.6 is 65% by number or more.

In the toner of the present invention, when the particle size of the toner particles is D (μm), the natural logarithm InD is plotted on the horizontal axis, and the horizontal axis is divided into a plurality of classes at intervals of 0.23. In the histogram showing the particle size distribution, the sum (M1) of the relative frequency (m1) of the toner particles included in the most frequent class and the relative frequency (m2) of the toner particles included in the class having the second highest frequency after the most frequent class. ) Is preferably 70% or more.

When the sum (M) of the relative frequency (m1) and the relative frequency (m2) is 70% or more, the dispersion of the particle size distribution of the toner particles becomes narrower. Thus, the occurrence of selective development can be reliably suppressed.

In the present invention, the above-mentioned histogram showing the number-based particle size distribution is obtained by plotting a natural logarithm InD (D: particle size of individual toner particles) at a plurality of classes (0 to 0) at intervals of 0.23.
0.23: 0.23 to 0.46: 0.46 to 0.69:
0.69 to 0.92: 0.92 to 1.15: 1.15
1.38: 1.38 to 1.61: 1.61 to 1.84:
1.84 to 2.07: 2.07 to 2.30: 2.30 to
2.53: 2.53 to 2.76...) Is a histogram showing the number-based particle size distribution, which is a particle size data of a sample measured by a Coulter Multisizer according to the following conditions. Is transferred to a computer via an I / O unit, and the computer creates the program using a particle size distribution analysis program.

Measurement conditions 1: Aperture: 100 μm 2: Sample preparation method: Electrolyte [ISOTON R-11
(Coulter Scientific Japan) 5
An appropriate amount of a surfactant (neutral detergent) is added to 0 to 100 ml, and the mixture is stirred, and 10 to 20 mg of a measurement sample is added thereto. This system is prepared by subjecting it to a dispersion treatment with an ultrasonic disperser for 1 minute.

With respect to toner particles, the development coefficient and the fine line width can be improved by using a toner composed of toner particles having a shape coefficient variation coefficient of 16% or less and a number variation coefficient of 27% or less in the number particle size distribution. Excellent reproducibility and stable cleaning properties can be formed over a long period of time.

Further, the inventors of the present invention have conducted a study focusing on the minute shape of each toner particle. As a result, the shape of the corner portion of the toner particle changes inside the developing device and becomes round, and the portion becomes round. It was found that blade wear occurred. Although the reason for this is not clear, it is presumed that stress is likely to be applied to the corners, which promotes blade wear at these corners.

In addition, when electric charges are applied to the toner particles by frictional charging, it is presumed that the electric charges tend to be concentrated particularly in the corner portions, and the electric charges of the toner particles are likely to be uneven.

That is, it is preferable that the ratio of the toner particles having no corners is 50% by number or more. Furthermore, by using a toner composed of toner particles whose number variation coefficient in the number particle size distribution is controlled to 27% or less,
It has been found that high-quality images can be formed over a long period of time with excellent developability and fine line reproducibility.

Further, it was also found that when the toner was made into a specific shape and the shape was made uniform, the blade wear was reduced and the charge amount distribution became sharp.

That is, it is also possible to use a toner in which the proportion of toner particles having a shape coefficient in the range of 1.2 to 1.6 is 65% by number or more, and the coefficient of variation of the shape coefficient is 16% or less. It has excellent developability, fine line reproducibility, and can form a high-quality image for a long period of time.

The coefficient of variation of the shape factor of the toner of the present invention is calculated from the following equation. Coefficient of variation (%) = (S / K) × 100 In the equation, S represents the standard deviation of the shape coefficient of 100 toner particles, and K represents the average value of the shape coefficient.

The number variation coefficient in the number particle size distribution of the toner is calculated from the following equation. Number variation coefficient (%) = (S / Dn) × 100 where S represents a standard deviation in the number particle size distribution, and Dn
Indicates a number average particle size (μm).

The toner particles having no corners according to the present invention are toner particles having substantially no projections on which electric charges are concentrated or projections which are easily worn by stress. The particles are called cornerless toner particles.
That is, as shown in FIGS. 1A, 1B, and 1C,
A circle having a major axis of toner particles L and a radius R of L / 10,
When the inside is rolled while contacting the inside at one point with respect to the toner particle peripheral line, a case where a circle does not substantially extend outside the toner is referred to as a toner particle having no corner. The case where the protrusion does not substantially protrude means that the protrusion where the protruding circle exists is one or less. In addition, the major axis of the toner particle is defined as the projected image of the toner particle on the plane interposed between two parallel lines,
The width of the particle at which the interval between the parallel lines is maximum.

The measurement of the toner having no corner was performed as follows. First, a photograph in which toner particles are enlarged by a scanning electron microscope is taken, and further enlarged to obtain a photographic image of 15,000 times. Next, the presence or absence of the corners is measured for this photographic image. This measurement was performed for 100 toner particles.

The toner of the present invention may be used as a one-component developer or a two-component developer. When used as a one-component developer, a non-magnetic one-component developer or a toner containing magnetic particles of about 0.1 to 0.5 μm in a toner to form a magnetic one-component developer can be used. be able to.

Further, it can be used as a two-component developer by mixing with a carrier. In this case, as magnetic particles of the carrier, metals such as iron, ferrite and magnetite,
Conventionally known materials such as alloys of these metals with metals such as aluminum and lead can be used. Particularly, ferrite particles are preferable. The magnetic particles have a volume average particle size of 15 to 100 μm, more preferably 25 to 8 μm.
It is preferably 0 μm.

The volume average particle size of the carrier is typically measured by a laser diffraction type particle size distribution analyzer “HELOS” equipped with a wet disperser (SYMPATIC (SYMPIC)
(ATEC)).

The carrier is preferably a carrier in which magnetic particles are further coated with a resin, or a so-called resin-dispersed carrier in which magnetic particles are dispersed in a resin. The resin composition for coating is not particularly limited, but, for example, an olefin resin, a styrene resin, a styrene-acrylic resin, a silicone resin, an ester resin, or a fluorine-containing polymer resin is used. The resin for forming the resin dispersion type carrier is not particularly limited, and a known resin can be used. For example, a styrene-acrylic resin, a polyester resin, a fluororesin, a phenol resin, or the like is used. be able to.

The toner of the present invention is fixed by passing a transfer material (also referred to as an image forming support or a transfer paper) on which a toner image is formed between a heating roller and a pressure roller constituting a fixing device. It is suitably used in an image forming method including a step of performing

Next, without being limited to this,
FIG. 2 shows an example of a configuration diagram illustrating an example of an image forming apparatus according to the present invention, and the image forming method of the present invention will be described.

In FIG. 2, based on information read by a document reading device (not shown), a semiconductor laser light source 11
Exposure light is emitted from. This is distributed by a polygon mirror 12 in the direction perpendicular to the plane of the paper of FIG. 2, and is radiated on the photoreceptor surface via an fθ lens 13 for correcting image distortion to form an electrostatic latent image. The photoreceptor 14 is provided with the charger 1 in advance.
5 and uniformly starts rotating clockwise in accordance with the image exposure timing.

The electrostatic latent image on the surface of the photoreceptor is developed by the developing unit 16 under the reverse developing condition, and the formed developed image is transferred to the transfer body 18 which has been conveyed at a proper timing by the action of the transferring unit 17. Transcribed. Further, the photoconductor 14 and the transfer member 18 are separated by a separator (separation pole) 19, and the developed image is transferred and carried on the transfer member 18, guided to a fixing device 40 and fixed.

The untransferred toner remaining on the photoreceptor surface is
The toner is cleaned by a cleaning device 21 of a cleaning blade type, and the residual charge is removed by a pre-charging exposure (PCL) 22, and is uniformly charged again by the charger 15 for the next image formation.

The transfer body P is typically plain paper, but is not particularly limited as long as it can transfer an unfixed image after development, and of course includes a PET base for OHP.

The cleaning blade 23 has a thickness of 1 mm.
A rubber-like elastic body of about 30 mm is used, and urethane rubber is most often used as a material.

Further, in the image forming apparatus of the present invention, a process cartridge in which a photoreceptor and at least one of a charger, an image exposing unit, a developing unit, a transfer unit, and a cleaning unit are integrally formed is formed. It is also a preferred embodiment to detachably attach to the apparatus body.

[0236]

Next, in order to specifically explain the effects of the present invention,
The present invention will be described by way of examples, but the embodiments of the present invention are not limited to these.

Production Examples of Calcium Stearate Calcium Stearate 1-5 Solids concentration 12.6% by mass, BET specific surface area 10 m ² /
g of lime milk slurry was prepared. This lime milk slurry was prepared using a dyno mill (manufactured by Simmer Enterprises:
(KDL-pilot type) to obtain a lime milk slurry having a BET specific surface area of 20 m ² / g and a sedimentation volume of 80 ml / 60 minutes. This lime milk slurry has a solid concentration of 40%.
Dehydrated so as to become.

On the other hand, 10 in a 3 liter kneader
Stearic acid heated to 0 ° C and melted (neutralization number 197) 57
0 g was prepared, and 222 g of lime milk having a solid concentration of 40% and 97.6 g of water were added to the molten stearic acid. This compounding ratio is, when converted, higher fatty acid / Ca
(OH) ₂ / water (molar ratio) = 2 / 1.2 / 12.8. In this state, the mixture was mixed for 5 to 30 minutes to terminate the reaction between stearic acid and calcium hydroxide.

The reaction product was dried under reduced pressure at 100 ° C. to obtain a calcium soap. Calcium soaps resulting was IR analysis, peaks of the carboxyl groups of 1700 cm ^-1 is, has changed to the peak of carboxylate 1600 cm ^-1, it was confirmed that calcium stearate is formed. By changing the reaction time and the drying time under reduced pressure, calcium stearate 1 to 5 shown in Table 1 were obtained.

Calcium stearate 6 Calcium stearate 6 shown in Table 1 was obtained in the same manner as in preparation of calcium stearate 1 to 5 except that 399 g of stearic acid and 171 g of palmitic acid were used instead of 570 g of stearic acid.

[0241]

[Table 1]

Production Example of Inorganic / Organic Composite Particles A surface having a primary particle diameter of 30 nm was coated with tin oxide on 100 g of styrene-acryl organic fine particles having an average particle diameter of 1.0 μm (electric resistance: 6.6 × 10 ¹³ Ω · cm). Treated titanium oxide particles (trade name: ET-300W, manufactured by Ishihara Sangyo Co., Ltd.)
g was added and mixed with a turbula mixer. Then, the particles were treated with a hybridizer (manufactured by Nara Machinery Co., Ltd.) with a modified pulverizer at a peripheral speed of 100 m / sec for 3 minutes to produce inorganic / organic composite fine particles having titanium oxide fixed on the surface of the organic fine particles. This is designated as “inorganic / organic composite fine particles 1”.

The electric resistance of the inorganic / organic composite fine particles 1 is 4.
It was 8 × 10 ⁸ Ω · cm. Example of Production of Resin Particles for Toner (Latex: 1HML) (1) Preparation of Core Particles (First Stage Polymerization) Anion-based interface in a 5000 ml separable flask equipped with a stirrer, temperature sensor, cooling pipe, and nitrogen introduction device Activator (Sodium dodecyl sulfonate: SD
S) A surfactant solution (aqueous medium) in which 7.08 g was dissolved in 3010 g of ion-exchanged water was charged, and the solution was added under a nitrogen stream.
The internal temperature was raised to 80 ° C. while stirring at a stirring speed of 0 rpm.

To this surfactant solution was added 9.2 g of a polymerization initiator (potassium persulfate: KPS) in 200 g of ion-exchanged water.
Was added, and the temperature was adjusted to 75 ° C., and then 70.1 g of styrene and n-butyl acrylate 1 were added.
A monomer mixture composed of 9.9 g and 10.9 g of methacrylic acid was added dropwise over 1 hour, and the system was heated and stirred at 75 ° C. for 2 hours to perform polymerization (first-stage polymerization). Latex (a dispersion of resin particles composed of a high molecular weight resin) was prepared. This is designated as “latex (1H)”.

(2) Formation of Intermediate Layer (Second Stage Polymerization) In a flask equipped with a stirrer, styrene 1
A compound represented by the above formula (19) was added to a monomer mixture comprising 05.6 g, n-butyl acrylate 30.0 g, methacrylic acid 6.4 g, and n-octyl-3-mercaptopropionate 5.6 g. Hereinafter, "Example compound (1
9)) was added, and the mixture was heated to 80 ° C. and dissolved to prepare a monomer solution.

On the other hand, an anionic surfactant (SDS)
A surfactant solution obtained by dissolving 1.6 g in 2700 ml of ion-exchanged water was heated to 80 ° C.
After adding 28 g of the latex (1H), which is a dispersion liquid of core particles, in terms of solid content, using a mechanical dispersing machine “CLEARMIX (CLEARMIX)” (manufactured by M-Technic) having a circulation path, the exemplified compound ( The monomer solution of (19) is mixed and dispersed to obtain a uniform dispersed particle diameter (284 n).
(Emulsion liquid) containing emulsified particles (oil droplets) having m)
Was prepared.

Next, to this dispersion liquid (emulsion liquid) were added an initiator solution obtained by dissolving 5.1 g of a polymerization initiator (KPS) in 240 ml of ion-exchanged water, and 750 ml of ion-exchanged water. Polymerization (second stage polymerization) is performed by heating and stirring at 3 ° C. for 3 hours, and latex (a dispersion of composite resin particles having a structure in which the surface of resin particles composed of a high molecular weight resin is coated with an intermediate molecular weight resin) is used. Obtained.
This is referred to as “latex (1HM)”.

(3) Formation of outer layer (third stage polymerization) 7.4 g of a polymerization initiator (KPS) was added to 200 ml of ion-exchanged water to the latex (1HM) obtained as described above.
Was added thereto, and 300 g of styrene and n-butyl acrylate 95 were added under a temperature condition of 80 ° C.
g, 15.3 g of methacrylic acid, and 10.4 g of n-octyl-3-mercaptopropionate were dropped over 1 hour. After the completion of the dropping, polymerization (third stage polymerization) is carried out by heating and stirring for 2 hours, and then cooled to 28 ° C. to form a latex (a central portion composed of a high molecular weight resin, an intermediate layer composed of an intermediate molecular weight resin, A dispersion of composite resin particles having an outer layer made of a molecular weight resin, wherein the intermediate layer contains the exemplary compound (19))
I got This latex is called “latex (1HML)”
And

The composite resin particles constituting the latex (1HML) were 138,000, 80,000 and 1
It has a peak molecular weight of 3,000,
The number average particle diameter of the composite resin particles was 102 nm.

[Preparation Example 2 of Composite Resin Particles] (1) Preparation of core particles (first stage polymerization): In a flask equipped with a stirrer, 105.6 g of styrene, n-
30.0 g of butyl acrylate, 6.4 g of methacrylic acid
72.0 g of a compound represented by the above formula 16) “described as an exemplary compound (16)” was added to a monomer mixture solution consisting of
The mixture was heated to 80 ° C. and dissolved to prepare a monomer solution.

On the other hand, an anionic surfactant (SDS)
A surfactant solution obtained by dissolving 1.6 g in 2700 ml of ion-exchanged water was heated to 80 ° C.
Mechanical dispersion machine with a circulation path "CLEARMIX (CL
EARMIX) ”(manufactured by M-Technic Co., Ltd.) to mix and disperse the monomer solution of Exemplified Compound (16) to obtain a dispersion (emulsion containing emulsified particles (oil droplets) having a uniform dispersed particle diameter (268 nm). Liquid).

Next, to this dispersion liquid (emulsion liquid) were added an initiator solution obtained by dissolving 5.1 g of a polymerization initiator (KPS) in 240 ml of ion-exchanged water, and 750 ml of ion-exchanged water. Polymerization (first-stage polymerization) was carried out by heating and stirring at 3 ° C. for 3 hours to prepare a latex (a dispersion of resin particles composed of a high molecular weight resin). This is designated as “latex (2H)”.

(2) Formation of outer layer (second stage polymerization): An initiator obtained by dissolving 14.8 g of a polymerization initiator (KPS) in 400 ml of ion-exchanged water in the latex (2H) obtained as described above. The solution was added, and a monomer mixture comprising 600 g of styrene, 190 g of n-butyl acrylate, 30.0 g of methacrylic acid, and 20.8 g of n-octyl-3-mercaptopropionate was added at 80 ° C. under a temperature condition of 1 g. It was dropped over time. After completion of the dropping, the mixture is polymerized by heating and stirring for 2 hours (second-stage polymerization), and then cooled to 28 ° C. to form a latex (having a central portion composed of a high molecular weight resin and an outer layer composed of a low molecular weight resin. Thus, a dispersion of composite resin particles containing the exemplary compound (16) in the center was obtained. This latex is referred to as “latex (2HL)”.

The composite resin particles constituting the latex (2HL) had peak molecular weights at 168,000 and 11,000, and the weight average particle diameter of the composite resin particles was 126 nm.

[Production Examples 1 to 4 of colored particles] 59.0 g of sodium n-dodecyl sulfate was added to 1600 ml of ion-exchanged water.
Was stirred and dissolved. While stirring the solution, carbon black “REGAL 330” (Cabot) 420.
0 g was gradually added, and then dispersion treatment was performed using “CLEARMIX” (manufactured by M-Technic) to prepare a dispersion of colorant particles (hereinafter, referred to as “colorant dispersion”). The particle size of the colorant particles in this colorant dispersion is measured by an electrophoretic light scattering photometer “ELS-800”.
It was 98 nm in weight average particle diameter when measured using (manufactured by Otsuka Electronics Co., Ltd.).

420.7 g of the latex (1HML) obtained in Preparation Example 1 of the composite resin particles (in terms of solid content), 900 g of ion-exchanged water, and 166 g of a colorant dispersion were introduced into a temperature sensor, a cooling pipe, and nitrogen introduction. The mixture was stirred in a reaction vessel equipped with an apparatus, a stirrer, and a monitoring device for particle size and shape. After adjusting the internal temperature to 30 ° C., a 5 mol / liter aqueous sodium hydroxide solution was added to the solution to adjust the pH to 11.0.

Subsequently, magnesium chloride hexahydrate12.
An aqueous solution obtained by dissolving 1 g in 1000 ml of ion-exchanged water,
The solution was added at 30 ° C. over 10 minutes with stirring. After standing for 3 minutes, heating was started, and the temperature of the system was raised to 90 ± 3 ° C. over 6 to 10 minutes (heating rate = 10 ° C./min). In this state, the particle size of the associated particles was measured with a “Coulter counter TA-II”, and when the volume average particle size became 5.5 μm, 80.4 g of sodium chloride was added to ion-exchanged water 1.
An aqueous solution dissolved in 000 ml was added to stop the particle growth, and as a maturing treatment, the mixture was heated and stirred at a liquid temperature of 85 ± 2 ° C. for 0.5 to 15 hours to continue the fusion. Thereafter, the mixture was cooled to 30 ° C. under the condition of 8 ° C./min, the pH was adjusted to 2.0 by adding hydrochloric acid, and the stirring was stopped. The generated associated particles are filtered using a Nutsche,
It is repeatedly washed with ion-exchanged water, and then dried at a suction air temperature of 60 ° C. using a flash jet drier, and then dried at a temperature of 60 ° C. using a fluidized-bed dryer. Was obtained. In the monitoring of the salting-out / fusion step and the shape control step, by controlling the number of rotations of stirring and the heating time, the coefficient of variation of the shape and the shape coefficient is controlled, and the variation coefficient of the particle size and the particle size distribution can be arbitrarily set. By adjustment, colored particles 1 to 4 having the shape characteristics and the particle size distribution characteristics shown in Table 2 were obtained.

[Production Examples 5 to 8 of Colored Particles] In place of latex (1HML), 420.7 g (in terms of solid content) of the latex (2HL) obtained in Preparation Example 2 of composite resin particles
Was used, and colored particles 5 to 8 having the shape characteristics and particle size distribution characteristics shown in Table 2 were obtained in the same manner as in Colored Particle Production Examples 1 to 4, except that the aging treatment time was changed.

[0259]

[Table 2]

Colored particles 1 to 8 obtained as described above
Each having a hydrophobic silica (number average primary particle size = 10n)
m, degree of hydrophobicity = 63) at a ratio of 1.0 mass%, and hydrophobic titanium oxide (number average primary particle diameter =
(25 nm, degree of hydrophobicity = 60) at a ratio of 0.8% by mass, and mixed with a Henschel mixer.

Further, 0.01% by mass of calcium stearate, 1% by mass of inorganic / organic composite fine particles, or 1% by mass of strontium titanate shown in Table 3 were added and mixed by a Henschel mixer to prepare toners 1 to 12.

The toner to which no calcium stearate was added was designated as Comparative Toner 1. Further, for comparison, a toner to which zinc stearate (Zinc Stearate D, manufactured by NOF Corporation) is added is referred to as Comparative Toner 2.

The shape and particle size of these colored particles are not changed by the addition of an external additive.

[0264]

[Table 3]

Preparation of Carrier Preparation of Ferrite Core Particles After 22 mol% of MnO and 78 mol% of Fe ₂ O ₃ were pulverized in a wet ball mill for 2 hours, mixed and dried, and then dried.
It was calcined by holding at 00 ° C. for 2 hours, and this was pulverized by a ball mill for 3 hours to form a slurry. A dispersant and a binder were added, and the mixture was granulated and dried by a spray drier, and then subjected to main firing at 1200 ° C. for 3 hours to obtain ferrite core material particles having an average grain diameter of 5.2 μm and a resistance of 4.3 × 108.

Resin Coating First, cyclohexyl methacrylate / methyl methacrylate (methyl methacrylate) was prepared by an emulsion polymerization method using sodium benzenesulfonate having an alkyl group having 12 carbon atoms as a surfactant at a concentration of 0.3 mass% in an aqueous medium. A copolymer having a copolymerization ratio of 5/5) was synthesized, and the volume average primary particle size was 0.1 μm, the weight average molecular weight (Mw) was 200,000,
Number average molecular weight (Mn) 91,000, Mw / Mn = 2.
2. A resin fine particle having a softening point temperature (Tsp) of 230 ° C. and a glass transition temperature (Tg) of 110 ° C. was obtained. The resin fine particles azeotroped with water in an emulsified state, and the residual monomer content was 510 ppm.

Next, 100 parts by mass of the ferrite core material particles and 2 parts by mass of the resin fine particles were put into a high-speed stirring mixer equipped with stirring blades, and stirred and mixed at 120 ° C. for 30 minutes.
A resin-coated carrier having a volume average particle diameter of 61 μm was obtained by using the action of a mechanical impact force.

Production of Developer Each of the colored particles (toner) to which the external additive was added,
The developer was mixed with a carrier to prepare a developer having a toner concentration of 6% by mass. These developers are referred to as Developers 1 to 12 and Comparative Developers 1 and 2, respectively, corresponding to Colored Particles 1 to 12 and Comparative Colored Particles 1 and 2.

Production of Photoreceptor Polyamide resin Amilan CM-8000 (Toray) 3
0 g of methanol 900 ml, 1-butanol 100 m
1 and mixed at 50 ° C. under heating. This liquid was applied on a cylindrical aluminum conductive support having an outer diameter of 60 mm and a length of 360 mm to form a 0.5 μm thick intermediate layer.

Next, 10 g of a silicone resin KR-5240 (manufactured by Shin-Etsu Chemical Co., Ltd.) was dissolved in 1000 ml of t-butyl acetate, and Y-TiOPc (JP-A 64-17066) was added thereto.
No., Fig. 1) 10 g was mixed and 20
After time dispersion, a coating solution for the charge generation layer was obtained. This liquid was used to coat the intermediate layer to form a 0.3 μm thick charge generation layer.

Next, 150 g of CTM (T-1: N- (4-methylphenyl) -N- {4- (β-phenylstyryl) phenyl} -p-toluidine) and a viscosity average molecular weight of 2
200 g of 10,000 polycarbonate resin Iupilon Z-200 (manufactured by Mitsubishi Gas Chemical Co., Ltd.) was treated with 1,2-dichloroethane 10
The solution was dissolved in 00 ml to obtain a charge transport layer coating solution. This liquid was used to coat the charge generation layer on a circular slide hopper, and then dried at 100 ° C. for 1 hour to form a charge transport layer having a thickness of 22 μm. Thus, a photoreceptor (P1) including the intermediate layer, the charge generation layer, and the charge transport layer was obtained. Next, CTM (T-1) 30 is placed on the surface of the photoconductor (P1).
g and a viscosity average molecular weight of 80,000 polycarbonate resin Iupilon Z-800 (manufactured by Mitsubishi Gas Chemical Co., Ltd.) A circular slide hopper is formed on the charge transport layer using a coating solution obtained by dissolving 50 g of a polycarbonate resin in 1,000 ml of 1,2-dichloroethane. And then dried at 100 ° C. for 1 hour to form an overcoat layer having a thickness of 5 μm.
2) was obtained.

Examples 1 to 12 and Comparative Examples 1 and 2 Using the developers 1 to 12 and the comparative developers 1 and 2, a commercially available digital copying machine, Satios Konica 7 manufactured by Konica Corporation was used.
030 in a high-temperature and high-humidity environment (temperature 33 ° C., relative humidity 80%) using a remodeling machine equipped with a photoconductor (P2).
By performing an actual photographing test for continuously forming 300,000 images having a pixel rate of 15%, the amount of blade wear, slippage,
The image blur and the environmental dependence of the image density were evaluated.

Examples 1 to 12 and Comparative Examples 1 and 2 correspond to the developer No.

Abrasion of Blade After printing 100,000 sheets, the cleaning blade was removed from the cleaning device, and the length of the portion disappeared by abrasion was measured with a laser microscope. There is no problem if the amount of wear is within 10 μm.

Slip loss The toner was picked out from the cleaning device on the white background of the image on the photosensitive member, and the number of sheets detected as image stain was evaluated.

Image blur A character image having a character size of 5 points is formed on the entire image.
The evaluation was performed based on the number of sheets until the image was locally blurred or a portion where the toner spreads around the image was detected.

Environmental Dependence of Image Density The maximum image density of the solid image portion was measured with a Macbeth reflection densitometer. The difference in image density between the high-temperature and high-humidity environment (33 ° C. 80% RH) and the low-temperature and low-humidity environment (10 ° C. 20% RH) is “◎” when less than 0.05, “」 ”when 0.05 to 0.1
0.1 or more was regarded as “x”.

The results are shown in Table 4.

[0279]

[Table 4]

It can be seen that Examples 1 to 12 in the present invention have no problem in any property, but Comparative Examples 1 and 2 outside the present invention have a problem in any property.

[0281]

According to the present invention, it is possible to provide a method for increasing the durability of the photosensitive member itself, the toner for developing an electrostatic latent image acting thereon, and the cleaning device when the photosensitive member is repeatedly used. More specifically, an electrostatic latent image developing toner that eliminates wear of a cleaning blade, slippage of toner on a photoreceptor surface during cleaning or image blur due to toner sticking, and fluctuation in image density due to temperature and humidity environment during use. And an image forming method and an image forming apparatus using the same.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating toner particles having no corners.

FIG. 2 is a configuration diagram of an image forming apparatus.

[Explanation of symbols]

 14 Photoconductor 15 Charger 16 Developing device 17 Transfer device 18 Transfer material 40 Fixing device

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court ゛ (Reference) G03G 9/08 374 G03G 9/08 381 321 (72) Inventor Yoshiaki Kobayashi 2970, Ishikawacho, Hachioji-shi, Tokyo Konica In-house company (72) Inventor Hajime Tadokoro 2970, Ishikawa-cho, Hachioji-shi, Tokyo Konica Corporation (72) Inventor Hideaki Morita 2970, Ishikawa-cho, Hachioji-shi, Tokyo Konica Corporation F-term (reference) 2H005 AA08 AA15 AB03 CA30 EA05 EA06 EA10 2H068 AA03 AA13 BB25 BB52

Claims (21)

[Claims] 1. An electrostatic latent image developing toner obtained by forming toner particles in an aqueous medium, wherein the toner contains a fatty acid calcium salt as an external additive. Electrostatic latent image developing toner. 2. The fatty acid calcium salt has a water content of 0.1 to 2.5% by mass and a free fatty acid content of 0.01 to 0.1% by mass.
The toner for developing an electrostatic latent image according to claim 1, wherein the content is 7% by mass. 3. The toner for developing an electrostatic latent image according to claim 1, wherein the fatty acid calcium salt is calcium stearate. 4. The method according to claim 1, wherein the resin particles are obtained by aggregating and fusing at least resin particles in an aqueous medium.
4. The toner for developing an electrostatic latent image according to claim 1. 5. The toner according to claim 1, wherein the toner has an average particle diameter of 0.1 to 5.0.
The average primary particle size is 5 to 100 μm on the surface of organic fine particles.
An inorganic / organic composite fine particle to which an inorganic fine particle of nm is fixed is contained as an external additive.
5. The toner for developing an electrostatic latent image according to any one of 4. 6. The toner according to claim 1, wherein the number average particle diameter of the toner is 3 to 8 μm, the variation coefficient of the shape coefficient is 16% or less, and the number variation coefficient in the number particle size distribution is 27% or less. 6. The toner for developing an electrostatic latent image according to any one of items 5 to 5. 7. The toner according to claim 1, wherein the number average particle diameter of the toner is 3 to 8 μm, and the ratio of the toner particles having a shape factor in the range of 1.0 to 1.6 is 65% by number or more. The toner for developing an electrostatic latent image according to any one of claims 1 to 5. 8. The toner according to claim 1, wherein the number average particle diameter of the toner is 3 to 8 μm, and the ratio of toner particles having a shape coefficient in the range of 1.2 to 1.6 is 65% by number or more. The toner for developing an electrostatic latent image according to claim 1. 9. The toner according to claim 1, wherein the number average particle diameter of the toner is 3 to 8 μm, and the ratio of the toner particles having no corners is 50% by number or more. Electrostatic latent image developing toner. 10. When the particle diameter of the toner is D (μm), the natural logarithm lnD is plotted on the horizontal axis, and the horizontal axis is 0.23.
The relative frequency (m1) of the toner particles included in the most frequent class in the histogram showing the number-based particle size distribution divided into a plurality of classes at intervals, and the toner particles included in the class having the next highest frequency after the most frequent class Sum (M) with relative frequency (m2)
The toner for developing an electrostatic latent image according to claim 1, wherein the ratio is 70% or more. 11. The ratio of toner having no corners is 50% by number or more, and the number variation coefficient in the number particle size distribution is 27%.
The electrostatic latent image developing toner according to claim 1, wherein: 12. The toner particles having a shape coefficient in the range of 1.2 to 1.6, wherein the proportion of toner particles is 65% by number or more and the coefficient of variation of the shape coefficient is 16% or less. The electrostatic latent image developing toner according to claim 1. 13. A toner obtained by salting out, aggregating, and fusing a composite resin particle obtained by a multi-stage polymerization method and a colorant particle, wherein the toner is formed in a region other than the outermost layer of the composite resin particle. The toner for developing an electrostatic latent image according to claim 1, wherein a toner containing a release agent is used. 14. A gel permeation chromatography (GPC) peak or shoulder of at least 100,000-1,000,000, and 1,000-1,000.
14. The toner for developing an electrostatic latent image according to claim 1, wherein a toner resin existing at 50,000 is used. 15. A gel permeation chromatography (GPC) peak or shoulder of at least 100,000-1,000,000, and 25,000.
2. The toner resin according to claim 1, wherein said toner resin is present in an amount of from 1,000 to 25,000.
4. The toner for developing an electrostatic latent image according to any one of 3. 16. The electrostatic latent image according to claim 1, comprising a resin, a release agent and a colorant, and having a crushing strength index of 0.1 to 0.8. Image developing toner. 17. An electrostatic latent image formed on an organic photoconductor is developed with a developer containing toner, and a toner image visualized by the development is transferred from the organic photoconductor to a transfer material. An image forming apparatus having a cleaning device for removing toner remaining on an organic photoreceptor, wherein the toner uses the toner for developing an electrostatic latent image according to any one of claims 1 to 16. Image forming device. 18. The organic photoreceptor has a structure in which a photosensitive layer is provided on a conductive support, and the surface layer of the photosensitive layer contains polycarbonate having an average molecular weight of 40,000 or more. Item 18. The image forming apparatus according to Item 17. 19. An electrostatic latent image formed on an organic photoreceptor is developed with a developer containing toner, and a toner image visualized by the development is transferred from the organic photoreceptor to a transfer material. 2. An image forming method according to claim 1, further comprising a cleaning unit for removing toner remaining on the organic photoconductor.
7. An image forming method, comprising using the toner according to any one of 6. 20. An organic photoreceptor having a structure in which a photosensitive layer is provided on a conductive support, and the surface layer of the photosensitive layer contains polycarbonate having an average molecular weight of 40,000 or more. Item 20. The image forming method according to Item 19. 21. An electrostatic latent liquid, characterized in that at least toner particles are formed by forming particles in an aqueous medium, and after drying the particles, 0.005 to 0.3% by mass of fatty acid calcium salt particles are externally added. A method for producing an image developing toner.