JP2002214823A - Image forming method and toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming method, in which a cleaning blade will not slip over a long period of time, a photoreceptor is less liable to wear, toner filming will not be caused, a stable image with little environmental dependence and slight lowering of halftone uniformity is obtained and the peripheries of fine letters are nearly clear and to provide a toner. SOLUTION: In the image forming method, having a step in which a latent image on a latent image forming body with an organic photosensitive layer, is developed with a toner to form an image and cleaning is carried out, the cleaning is carried out, using an elastic blade, a crossed axes angle ϕ between the holder of the elastic blade and the latent image forming body is <90 deg. and the toner contains 1.0-7.0% by the number of particles having <=3.17 μm and contains an abrasive external additive, having 0.5-5.0 μm for number average particle diameter and a metal salt of a fatty acid.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming method for forming an image by developing a latent image on a latent image forming body having an organic photosensitive layer using a toner, and a toner.

[0002]

2. Description of the Related Art At present, an organic photoconductor containing an organic photoconductive material is most widely used as a latent image carrier used in an electrophotographic image forming apparatus. Conventionally, the toner developed on the organic photoreceptor and remaining on the photoreceptor through the transfer process has been collected and discarded by a cleaning device. For example, an image forming method using a so-called toner recycling system, which returns the toner to the developing device and reuses the toner as a developing toner, has attracted attention.

However, the organic photoreceptor has a large contact energy with the toner which visualizes the electrostatic latent image formed on the photoreceptor, and the toner deteriorated by the stress from the conveying member is used repeatedly. Various problems tend to occur in cleaning in the system.

[0004] In the electrophotographic image forming method, digital image formation has become mainstream due to recent advances in digital technology. Digital image forming method is 1200
It is based on visualizing small dot images of pixels such as dpi (however, dpi represents the number of dots per 2.54 cm), and a high image quality technology that faithfully reproduces these small dot images. Is required.

One of the most important technologies for realizing this high image quality technology is a technology relating to a toner manufacturing method. Heretofore, for forming an electrophotographic image, a toner obtained by classifying a toner powder obtained by mixing and kneading a binder resin and a pigment and kneading them has been mainly used. The toner obtained through such a manufacturing process has a limit in making the particle size distribution of the toner particles uniform, and the particle size distribution and shape of the toner particles are insufficiently uniform. It is difficult to achieve sufficiently high image quality in an electrophotographic image using such a toner.

On the other hand, as means for achieving a uniform particle size distribution and shape of toner particles, an electrophotographic developer using a polymerized toner or an image forming method has been proposed. In the polymerized toner, since the raw material monomers are uniformly dispersed in an aqueous system and then polymerized to produce the toner, the particle size distribution and shape of the toner become uniform.

Here, when the polymerized toner is employed in an image forming apparatus using an organic photoreceptor, a new technical problem has arisen. That is, the polymerized toner is formed in a substantially spherical shape because the toner is formed after the monomer is dispersed in an aqueous system and polymerized. As is well known, the spherical residual toner has a high adhesive force to the surface of the organic photoreceptor and easily causes cleaning failure.

In particular, when the polymerized toner is applied to an image forming apparatus in which the above-described cleaning device is disposed immediately above a cylindrical organic photoreceptor, fine toner that does not cause a streak in an image is passed for a long time. Then, the toner that has slipped through the film is filmed on the photoreceptor, and an image flows under high temperature and high humidity, which causes a problem of image blur.

As a measure for preventing the toner filming, a technique of adding an abrasive external additive to the toner is known.

The abrasive external additive has the effect of polishing the surface of the photoreceptor and preventing filming of the photoreceptor due to discharge products such as toner, nitrogen oxides and ammonium nitrate. There was a problem that the photoconductor was worn out quickly and the life of the photoconductor was shortened.

[0011]

SUMMARY OF THE INVENTION The present inventors have found that the wear of the photoreceptor is reduced when the components of the fine powder (3.17 μm or less) of the toner are cut. This is because the toner fine powder component having a strong adhesive force to the photoconductor accumulates in the cleaning blade pressing portion and entrains the external additive released from the toner, thereby depleting the photoconductor. But,
The problem of photoreceptor filming could not be solved only by cutting the fine powder of the toner.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to reduce the wear of a cleaning blade, prevent slippage over a long period of time, reduce the depletion of a photoconductor, and extend the life of the photoconductor. Effective, no toner filming, less environmental dependency, less decrease in halftone homogeneity due to toner external additive burial, stable image obtained, little dust around small characters, easy to distinguish , An image forming method and a toner.

[0013]

The present inventors have conducted intensive studies and found that the object of the present invention can be attained by adopting one of the following constitutions.

[1] An image is formed by developing a latent image on a latent image forming body having an organic photosensitive layer using toner to form an image, and transferring the image to a transfer material. An image forming method having a step of cleaning the residual image of
The cleaning is performed by bringing the tip of the elastic blade supported by the holder into contact with the latent image forming body, the intersection angle φ between the holder of the elastic blade and the latent image forming body is less than 90 °, and the toner is Contains 1.0 to 7.0% of particles of 3.17 μm or less on a number basis, and has a number average particle size of 0.5 to
An image forming method, which is a toner containing a 5.0 μm abrasive external additive and a fatty acid metal salt.

[2] The image forming method according to [1], wherein the cleaned toner is returned to the developing step and reused.

[3] Toner is 3.17 μm on a number basis
The following particles are contained in an amount of 1 to 4.5%, and the number average particle diameter is 0.5.
The image forming method according to [1] or [2], further comprising an abrasive external additive having a thickness of from 3.0 to 3.0 μm.

[4] The toner contains an abrasive external additive in an amount of 0.1%.
Characterized by containing from 02 to 2.0 parts by mass [1] to
The image forming method according to any one of [3].

[5] The toner contains an abrasive external additive in an amount of 0.
Characterized by containing from 0.4 to 1.0 parts by mass [1] to
The image forming method according to any one of [4].

[6] The image forming method according to any one of [1] to [5], wherein the circularity coefficient of the abrasive external additive of the toner is 0.950 to 0.998.

[7] The abrasive external additive of the toner contains, on the surface of the organic fine particles, inorganic / organic composite fine particles in which inorganic fine particles having a number average primary particle diameter of 5 to 100 nm are fixed to a fixing degree of 20 to 75%. [1] to [6]
The image forming method according to claim 1.

[8] The abrasive external additive of the toner is strontium titanate [1] to [1].
The image forming method according to any one of [7].

[0022]

[9] Of the external additives present on the surface of the toner, those having a size of 0.005 to less than 0.025 μm
5 to 95% by number, 4 to 35% by number less than 0.025 to 0.080 μm, and 0.3 to 10% by weight of 0.080 to 0.500 μm [1] characterized in that a toner containing an external abrasive additive having a diameter of 0.5 to 5.0 μm is used.
The image forming method according to any one of the above items [8] to [8].

[10] The external additive of the toner is a) silica having a number average particle diameter of 0.005 to 0.015 μm, b)
Silica having a number average particle size of 0.020 to 0.080 μm,
c) titanium oxide having a number average particle size of 0.015 to 0.070 μm, and d) a number average particle size of 0.08 to 0.2 μm
Characterized in that a toner containing an abrasive external additive having a number average particle diameter of 0.5 to 5.0 μm in a toner to which titanium oxide is externally added is used.

The image forming method according to any one of [9].

[11] The toner has a shape coefficient variation coefficient of 16% or less, a number variation coefficient in a number particle size distribution of 27% or less, and a shape coefficient in a range of 1.0 to 1.6. The image forming method according to any one of [1] to [10], wherein a toner having a ratio of toner particles of 65% by number or more is used.

[12] In the toner, the proportion of toner particles having no corners is 50% by number or more, the number variation coefficient in the number particle size distribution is 27% or less, and the shape coefficient is 1.0%.
The image forming method according to any one of [1] to [10], wherein the ratio of the toner particles in the range from 1.6 to 1.6 is 65% by number or more.

[13] The toner has a shape factor of 1.2 to
Any one of [1] to [10], wherein the ratio of the toner particles in the range of 1.6 is 65% by number or more and the variation coefficient of the shape coefficient is 16% or less. Item.

[14] The particle diameter of the toner particles is D (μm)
, The natural logarithm lnD is taken on the horizontal axis, and the horizontal axis is divided into a plurality of classes at intervals of 0.23, and the relative frequency (m1) of the toner particles included in the most frequent class in the histogram showing the number-based particle size distribution And a toner having a sum (M) of 70% or more of the relative frequency (m2) of the toner particles included in the class having the highest frequency next to the most frequent class is [1] to [13]. ] The image forming method according to any one of the above items.

[15] The image forming method according to any one of [1] to [14], wherein the toner is obtained by polymerizing at least a polymerizable monomer in an aqueous medium.

[16] The image forming method according to any one of [1] to [15], wherein the toner is obtained by aggregating and fusing at least resin particles in an aqueous medium.

[17] The latent image on the latent image forming body having the organic photosensitive layer is developed using toner to form an image, and the image is transferred to a transfer material. Cleaning, the cleaning is performed by bringing the base of the elastic blade supported by the holder into contact with the latent image forming body, and the cleaning is performed with the elastic blade holder and the latent image. 2. The crossing angle φ formed by the formed body is less than 90 °, and the number of the toner is 3.
A toner containing 1.0 to 7.0% of particles having a particle size of 17 μm or less, an external abrasive additive having a number average particle size of 0.5 to 5.0 μm, and a metal salt of a fatty acid.

[18] 3.17 μm based on the number of toner
m containing 4.5% or less of particles [1]
7] The toner as described above.

[19] The toner according to [17] or [18], wherein the number average particle size of the abrasive external additive contained in the toner is 0.5 to 3.0 μm.

[20] The toner according to [1], wherein the toner contains 0.02 to 2.0 parts by mass of an abrasive external additive.
[7] The toner according to any one of [19] to [19].

[21] The toner is characterized in that the toner contains 0.04 to 1.0 parts by mass of an external abrasive additive.
7] The toner according to any one of [20].

[22] The toner according to any one of [17] to [21], wherein the circularity coefficient of the abrasive external additive of the toner is 0.950 to 0.998.

[23] The abrasive external additive of the toner has a number average primary particle diameter of 5 to 100 nm on the surface of the organic fine particles.
[17] to [2], wherein the inorganic fine particles are inorganic / organic composite fine particles having the inorganic fine particles fixed to a fixing degree of 20 to 75%.
2) The toner according to any one of the above items.

[24] The abrasive external additive of the toner is strontium titanate [17]
-The toner according to any one of [23] to [23].

[25] 65% of external additives present on the surface of the toner are 0.005 to less than 0.025 μm.
The number average particle diameter of the toner adhered or fixed at 4 to 35% by number and 0.080 to 0.500 μm at 0.3 to 10% by number. Wherein a toner containing an abrasive external additive having a particle size of 0.5 to 5.0 μm is used [17].
-The toner according to any one of [24] to [24].

[26] The external additive of the toner is a) silica having a number average particle diameter of 0.005 to 0.015 μm, b)
Silica having a number average particle size of 0.020 to 0.080 μm,
c) titanium oxide having a number average particle size of 0.015 to 0.070 μm, and d) a number average particle size of 0.08 to 0.2 μm
Any one of [17] to [25], wherein a toner in which a number average particle diameter of 0.5 to 5.0 μm is added to a toner to which titanium oxide is added externally is used. Item.

[27] The toner has a shape coefficient variation coefficient of 16% or less, a number variation coefficient in the number particle size distribution of 27% or less, and a shape coefficient in a range of 1.0 to 1.6. The toner according to any one of [17] to [26], wherein a toner having a ratio of toner particles of 65% by number or more is used.

[28] In the toner, the proportion of toner particles having no corners is 50% by number or more, the number variation coefficient in the number particle size distribution is 27% or less, and the shape coefficient is 1.0%.
The toner according to any one of [17] to [26], wherein the ratio of the toner particles in the range from 1.6 to 1.6 is 65% by number or more.

[29] The toner has a shape factor of 1.2 to
Any one of [17] to [26], wherein the ratio of the toner particles in the range of 1.6 is 65% by number or more and the variation coefficient of the shape coefficient is 16% or less. The toner according to Item.

[30] D (μm)
, The natural logarithm lnD is taken on the horizontal axis, and the horizontal axis is divided into a plurality of classes at intervals of 0.23, and the relative frequency (m1) of the toner particles included in the most frequent class in the histogram showing the number-based particle size distribution And a toner having a sum (M) of 70% or more of the relative frequency (m2) of the toner particles included in the class having the second highest frequency after the most frequent class [17] to [29]. ] The toner according to any one of the above items.

[31] The toner according to any one of [17] to [30], wherein the toner is obtained by polymerizing at least a polymerizable monomer in an aqueous medium.

[32] The toner according to any one of [17] to [30], wherein the toner is obtained by aggregating and fusing at least resin particles in an aqueous medium.

[0046]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The number-based particle size distribution of toner The toner of the present invention has a number-based particle size distribution of 3.17 μm.
It contains the following particles in an amount of 1.0 to 7.0% or less.
If it exceeds 7.0%, the wear of the blade and the photoreceptor is large,
If it is less than 1.0%, the vibration of the cleaning blade increases, and the toner that cannot be completely cleaned, that is, the so-called toner tends to easily pass through. More preferably, the content is 1.0 to 4.5%.

The particle diameter of the toner of the present invention is preferably 4.5 to 9 μm, more preferably 5 to 8 μm in number average particle diameter. The particle size can be controlled by changing 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 size is 4.5 to 9 μm, the transfer efficiency is increased, the halftone image quality is improved, and the image quality of fine lines and dots is improved.

The calculation of the particle size distribution of the toner and the measurement of the number average particle size can be performed using a Coulter Counter TA-II, a Coulter Multisizer, a SLAD1000 (a laser diffraction type particle size measuring device manufactured by Shimadzu Corporation) or the like. it can.

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.

Abrasive external additive Abrasive external additive is a number average particle size of 0.5 to 5.0.
μm metal oxide or inorganic particles composed of metal,
Or, it refers to inorganic / organic composite fine particles described later. In this particle size measurement, the major axis of 200 particles is measured with a scanning electron microscope, and the average diameter is determined.

The toner of the present invention preferably contains 0.02 to 2.0 parts by mass of an external abrasive additive. More preferably, the content is 0.04 to 1.0 parts by mass.
If the amount is more than 2.0 parts by mass, the amount of wear of the blade increases, and the cleaning property decreases. On the other hand, if the amount is less than 0.02 parts by mass, the effect of preventing toner filming on the photoconductor is reduced.

The circularity coefficient of the abrasive external additive of the present invention is preferably 0.950 to 0.998. More preferably, it is 0.980 to 0.990.

When the circularity coefficient is within this range, the slidability between the blade and the photoreceptor is improved, and fine vibration of the blade is reduced, so that the toner can be prevented from slipping through. If it exceeds 0.998, the abrasive external additive may slip through without accumulating in the cleaning section,
If it is less than 0.950, the amount of wear of the photoconductor increases. The measurement of the circularity coefficient is performed using a flow-type particle image analyzer FPIA-20.
00 (manufactured by Toa Medical Electronics Co., Ltd.) can be used.

Inorganic / organic composite fine particles In the present invention, inorganic / organic composite fine particles are preferably used as abrasive particles. 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 properties, polishing properties and 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 made of an acrylic polymer, a styrene polymer, a styrene-acryl polymer, or the like.

The acrylic polymer constituting the organic fine particles is a homopolymer or a copolymer obtained by polymerizing a monomer selected from acrylic acid or acrylic acid ester, methacrylic acid or methacrylic acid ester. Acrylic monomers used to obtain such an acrylic polymer include acrylic acid, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, propyl acrylate, and n-acrylate
-Octyl, dodecyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, α-methyl methacrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, methacryl Propyl acrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylamino methacrylate Ethyl and the like.

As the styrene monomer, 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-phenyl styrene,
p-Chlorostyrene, 3,4-dichlorostyrene and the like.

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 may be copolymerized if necessary. May be used. 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 copolymer constituting the organic fine particles is obtained by using one or more of the above acrylic monomers and one or more of the above styrene monomers. If necessary, one or more other monomers may be copolymerized. In this case, in the monomer composition, it is preferable to use the acrylic monomer and the styrene monomer in a ratio of 50% by mass or more. As the other monomer, acrylonitrile, methacrylonitrile, acrylic acid or methacrylic acid derivatives such as acrylamide, vinyl acetate, vinyl butyrate, vinyl esters such as vinyl benzoate, vinyl methyl ether, vinyl ether such as 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 size of the organic fine particles constituting the inorganic / organic composite fine particles is preferably from 0.1 to 4.5 μm, particularly from 0.2 to 3. 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 the 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. As means for spheroidizing the organic fine particles, 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 to form a sphere, a suspension polymerization method or And a method of synthesizing spherical organic fine particles by an emulsion polymerization method.

The means for fixing the inorganic fine particles to 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 to 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 fixing rate of the inorganic / organic composite fine particles is determined as follows. (BET specific surface area of inorganic / organic composite fine particles) / {(BET specific surface area of inorganic particles used) + (BET specific surface area of organic particles used)} × 100 Here, the BET specific surface area is an automatic specific surface area measuring device.
BE by GEMINI 2375 (manufactured by Shimadzu Corporation)
It was measured by the T one point method.

Abrasive external additives other than inorganic / organic composite fine particles In the present invention, examples of the abrasive external additives other than inorganic / organic composite fine particles include calcium titanate powder, barium titanate powder, magnesium titanate powder, and the like. There are strontium titanate powder, cerium oxide powder, 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 is particularly preferably used.

The step of mixing the external additive is a step of adding the external additive to the dried toner particles.

Examples of the apparatus used for adding the external additive include various known mixing apparatuses such as a turbular mixer, a Henschel mixer, a Nauta mixer, and a V-type mixer.

External Additives Other than Abrasive External Additives The external additives present on the toner surface preferably contain silica or titanium oxide in addition to the above-mentioned abrasive external additives. If necessary, alumina, tin oxide, iron oxide or the like may be used in combination.

In order to obtain particularly good cleaning properties,
It is preferable to externally add two kinds of silica having different number average particle diameters and two kinds of titanium oxides having different number average particle diameters.

The two types of silica having different number average particle sizes and the two types of titanium oxide having different number average particle sizes are as follows: a) silica having a number average particle size of 0.005 to 0.015 μm;
b) silica having a number average particle size of 0.020 to 0.080 μm, c) titanium oxide having a number average particle size of 0.015 to 0.070 μm, and d) number average particle size of 0.08 to 0.2.
It is preferable that titanium oxide of μm is externally added.

Process for Producing Silica Nucleus Silica used in the present invention is generally produced by a wet process or a dry process. In particular, a so-called silica produced by a dry process (vapor phase oxidation of a silicon halide compound) is used. What is called fumed silica is preferred from the viewpoint of fluidity. This is manufactured by a conventionally known technique. For example, it utilizes the thermal decomposition oxidation reaction of silicon tetrachloride gas in an oxyhydrogen flame, and the basic reaction formula is as follows.

SiCl ₄ + 2H ₂ + O ₂ → SiO ₂ + 4HCl Also, in this manufacturing process, another metal halide such as aluminum chloride or titanium chloride is used together with a silicon halide to produce a composite of silica and another metal oxide. It is also possible to obtain a fine powder, and the silica core in the present invention also includes them.

Small silica used a) Silica having a number average particle diameter of 0.005 to 0.015 μm is added in an amount of 100 parts of toner (without adding external additives).
It is preferable to add 0.1 to 0.8 parts by mass with respect to parts by mass.

Examples of commercially available fine silica powder include, for example, those commercially available under the following trade names.

AEROSIL (Nippon Aerosil) 13
0, 200, 200V, 200CF, 200FAD, 3
00, 300 CF, 80, and Cab-O-Sil (C
ABOT) M-5, MS-7D, MS-75D, H-
5, HS-5, EH-5, and Wacker HDK
(WACKER-CHFMIEGMBH) N20, S
13, V15, T30 and T40.

The following are examples of the silica subjected to the hydrophobic treatment. HDK H 2000 (Clariant) HDK H 2000/4 (Clariant) HDK H 3004 (Clariant) HDK H 2050EP (Clariant) HVK21 (Clariant) R972 (Nippon Aerosil) R974 (Nippon Aerosil) RX200 (Japan) Aerosil Co., Ltd.) RY200 (Japan Aerosil Co.) R202 (Nippon Aerosil Co.) R805 (Nippon Aerosil Co.) R812 (Nippon Aerosil Co.).

Large diameter silica to be used b) The number of parts of silica having a number average particle size of 0.020 to 0.080 μm is 0.2 to 1.2 parts by mass with respect to 100 parts by mass of toner (without adding external additives). It is preferable to add a part. More preferably, it is 0.3 to 0.8 parts by mass.

Examples of commercially available silica powders include those commercially available under the following trade names, for example.

AEROSIL (Japan Aerosil) OX
50, AEROSIL50, TT600, MOX80,
MOX170 etc.

The following are examples of the silica subjected to the hydrophobic treatment. TS630 (Cabot) NA-50H (Kao) RY-50 (Nippon Aerosil) NY-50 (Nippon Aerosil) NAX-50 (Nippon Aerosil) RX-50 (Nippon Aerosil) RM-50 (Nippon Aerosil) Titanium-based external additive The titanium oxide particles used in the present invention include those produced by a sulfuric acid method and a chlorine method, and include rutile type, anatase type, amorphous and the like.

The titanium crystals include rutile, anatase, rutile, mixed crystals of anatase, amorphous, and mixed types thereof, and all of them can be used. However, from the viewpoint of ensuring fluidity and reducing the environmental dependency of charging, titanium oxide in which the ratio of rutile-type titanium oxide to anatase titanium oxide is in the range of 2:98 to 45:55 by mass is preferably used. . In addition, the particle surface of the rutile-containing / anatase mixed titanium oxide may be made of aluminum, silicon,
It is preferable to coat one or more of titanium, zirconium and tin with a layer containing an element. That is, the particle surface before treatment with the silane coupling agent,
It is preferable to cover with a layer containing the predetermined element.

The reason why the layer is coated before the silane coupling agent treatment is performed is to adjust the chargeability and the resistance. The treatment amount of the element is preferably 3 to 20% by mass. 3
If the amount is less than 20% by mass, it is difficult to obtain the effect of adjusting the charge.
If it exceeds 0% by mass, coalescence of the particles occurs, which may not be preferable.

C) titanium oxide having a number average particle size of 0.015 to 0.070 μm;
It is preferable to add 0.1 to 1.0 part by mass to 0 part by mass. More preferably, it is 0.2 to 0.8 parts by mass.

The following are specific examples of titanium oxide fine particles. P-25 (made by Degussa); IT-
S, IT-PA, IT-PB (all manufactured by Idemitsu Kosan Co., Ltd.); R-820, R-830, R-680, CR-5
0, CR-60, A-100, A-220 (all manufactured by Ishihara Sangyo Co., Ltd.); MT-100SA, MT-150W, M
T-500B, MT-600B (both manufactured by Teika)
etc. Examples of the titanium oxide fine particles particularly subjected to the hydrophobic treatment include the following.

STT-30A (Titanium Industry Co., Ltd.) STT-30AS (Titanium Industry Co., Ltd.) STT-30S (Titanium Industry Co., Ltd.) T-805 (Nippon Aerosil Co., Ltd.) TTO-51 (Ishihara Sangyo Co., Ltd.) TAF-1500S (Fuji Titanium Co., Ltd.) MT-100S (Taika) MT-100T (Taika) and the like.

Large Diameter Titanium Oxide Used d) The number of parts of titanium oxide having a number average particle diameter of 0.08 to 0.2 μm is from 0.2 to 1 part per 100 parts by weight of toner (without adding external additives). It is preferable to add 2 parts by mass. More preferably, it is 0.3 to 1.0 part by mass.

Examples of commercially available titanium oxide particles include those commercially available under the following trade names.

TTO-51 (A) (Ishihara Sangyo) TTO-51 (B) (Ishihara Sangyo) TAF-620 (Fuji Titanium).

Examples of the titanium oxide fine particles particularly subjected to the hydrophobic treatment are as follows.

STT-60J (Titanium) JA-1 (Taica) JA-3 (Taica) JA-4 (Taica) JA-5 (Taica) TAF-520 (Fuji Titanium) TAF-520AS (Fuji Titanium) TAF-520K (Fuji Titanium).

Coupling agent preferably used It can be obtained by treating hydrophilic fine particles with a silane coupling agent such as methyltrimethoxysilane, methyltriethoxysilane or octyltrimethoxysilane. Specific coupling agents are shown below.

CH ₃ (CH ₂ ) ₂ SiCl ₃ CH ₃ (CH ₂ ) ₅ SiCl ₃ CH ₃ (CH ₂ ) ₇ SiCl ₃ CH ₃ (CH ₂ ) ₉ SiCl ₃ CH ₃ (CH ₂ ) ₉ Si (OCH ₃ ) ₃ CH ₃ (CH ₂ ) ₉ Si (CH ₃ ) Cl ₂ CH ₃ (CH ₂ ) ₂ Si (OCH ₃ ) ₃ CH ₃ (CH ₂ ) ₂ Si (CH ₃ ) (OCH ₃ ) ₂ CH ₃ (CH _{2) 5 Si (OCH 3)} 3 CH 3 (CH 2) 5 CONH (CH 2) 2 Si (OC 2 H 5) 3 CH 3 (CH 2) 4 COO (CH 2) 2 Si (OCH 3) 3 CH _{3 (CH 2) 9 Si (} OCH 3) 3 CH 3 (CH 2) 9 Si (CH 3) (OCH 3) 2 CH 3 (CH 2) 7 SO 2 NH (CH 2) 3 Si (OC 2 H 5 )
_{3 CH 3 (CH 2) 8} (CH 2) 2 Si (OCH 3) 3 CF 3 (CH 2) 2 SiCl 3 CF 3 (CF 2) 5 SiCl 3 CF 3 (CF 2) 5 (CH 2) 2 SiCl _{3 CF 3 (CF 2) 7} (CH 2) 2 SiCl 3 CF 3 (CF 2) 7 CH 2 CH 2 Si (OCH 3) 3 CF 3 (CF 2) 7 (CH 2) 2 Si (CH 3) Cl _{2 CF 3 (CH 2) 2} Si (OCH 3) 3 CF 3 (CH 2) 2 Si (CH 3) (OCH 3) 2 CF 3 (CF 2) 3 (CH 2) 2 Si (OCH 3) 3 CF _{3 (CF 2) 5 CONH (} CH 2) 2 Si (OC 2 H 5) 3 CF 3 (CF 2) 4 COO (CH 2) 2 Si (OCH 3) 3 CF 3 (CF 2) 7 (CH 2) _{2 Si (OCH 3) 3 CF} 3 (CF 2) 7 (CH 2) 2 Si (CH 3) (OCH 3) 2 CF 3 (CF 2) 7 SO 2 NH (CH 2 ) ₃ Si (OC ₂ H ₅ )
₃ CF ₃ (CF ₂ ) ₈ (CH ₂ ) ₂ Si (OCH ₃ ) _{3 and the} like.

Further, it can be obtained by a polysiloxane treatment. The treatment amount is silica or titanium oxide 1
The amount is 10 to 100% by mass, preferably 20 to 70% by mass with respect to 00% by mass. The processing amount is 1
When the amount is less than 0% by mass, not only a material having low hydrophobicity can be obtained, but also a firm fixation occurs during drying, resulting in poor dispersion. When the amount exceeds 100% by mass, the decrease in specific surface area is large, which is not preferable. .

From the viewpoint of increasing the fluidity and the environment resistance of charging, the hydrophobicity of the silica particles is 30 to 100, particularly preferably 60 to 95, and the hydrophobicity of titanium oxide is 2 to 2.
It is 0 to 90, particularly preferably 30 to 70.

<Various Measurement Methods> (1) Specific Surface Area The specific surface area was measured by an automatic specific surface area measuring apparatus GEMINI 2375 (manufactured by Shimadzu Corporation) by the BET one-point method. (2) Degree of hydrophobicity 0.1 g of hydrophobic titanium oxide fine powder was added to 50 ml of water, and methanol was introduced into the water at a rate of 2 ml / min with stirring with a microtube pump to prevent sedimentation of the fine powder. The methanol concentration and the methanol concentration when completely wetted were determined.

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

In the present invention, when the external additive present on the toner surface is less than 0.005 to 0.025 μm,
It is preferable that 5 to 95% by number, 4 to 35% by number of 0.025 to less than 0.080 µm, and 0.3 to 10% by number of 0.080 to 0.500 µm.

The particle diameter of the external additive on the surface of the toner was measured with a field effect scanning electron microscope (JSM6400F, acceleration voltage 5 k
V, 40,000 times magnification), and the number was counted by an image analyzer.

The external additive adhering with a particle size of 0.005 to less than 0.025 μm is preferably 65 to 95% by number from the viewpoint of obtaining high fluidity and making the charge amount distribution uniform.
If it is less than 65% by number, the fluidity becomes insufficient, and problems such as poor cleaning and generation of toner granules tend to occur. On the other hand, when the content is more than 95% by number, the external additive is easily buried when the stirring is performed for a long time in the developing device or when the toner recycling system is employed, which is liable to cause fogging and poor cleaning due to a decrease in the charge amount.

The external additive adhering with a particle size of 0.025 to less than 0.080 μm is a region having both a burying prevention function and a fluidity imparting function, and is adhering at a rate of 4 to 35% by number. Is preferred. Particularly preferably, 5 to 20
%.

If the content is less than 4% by number, the burial prevention function is insufficient.
If the content is more than 35% by number, a part of the external additive is detached from the toner, and there is a problem that a frictional charging member such as a carrier or a member such as a photoconductor is contaminated.

The external additive adhering with a particle size of 0.080 to 0.500 μm has a function of improving transferability in addition to a function of preventing burial, and is 0.3 to 10% by number.
Is preferably adhered at a ratio of Particularly preferably, it is 0.8 to 5% by number. If the amount is less than 0.3% by number, the above-mentioned effect is not exhibited. If the amount is more than 10% by weight, some external additives are detached, and a problem arises that a frictional charging member such as a carrier or a member such as a photoconductor is contaminated. Cheap.

Fatty Acid Metal Salts As fatty acid metal salts that can be used as an external additive in the present invention, preferably higher fatty acid metal salts can be mentioned. Specific examples of such higher fatty acid metal salts include zinc stearate, aluminum stearate, copper stearate, magnesium stearate and the like; zinc oleate, manganese oleate, iron oleate, copper oleate, Metal oleate such as magnesium oleate; metal palmitate such as zinc palmitate, copper palmitate and magnesium palmitate; metal linoleate such as zinc linoleate, zinc linoleate; zinc ricinoleate, lithium ricinoleate And ricinoleic acid metal salts.

From the viewpoint of preventing blade wear and photoreceptor wear, fatty acid calcium salts are particularly preferably used.

Specific examples of the fatty acid calcium salt include calcium undecylate, calcium laurate, calcium tridecylate, calcium dodecylate, calcium myristate, calcium palmitate, calcium pentadecylate, calcium stearate, calcium behenate, calcium heptadecylate, Calcium arachinate, calcium montanate, calcium oleate,
Long-chain fatty acid calcium such as calcium linoleate, calcium arachidonic acid and calcium behenate can be mentioned, and calcium stearate is particularly preferred. The fatty acid component is a single or mixed fatty acid.

The production method includes a melting method in which a fatty acid and calcium oxide or calcium hydroxide are melt-reacted at a temperature not lower 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.

Water Content of Calcium Fatty Acid and Free Fatty Acid The water content of calcium fatty acid is preferably from 0.1 to 2.5% by mass, from the viewpoint of improving the stability of charging humidity, and from 0.3 to 2.5% by mass.
1.2% is particularly preferred. If the water content is large, image blur easily occurs under high temperature and high humidity.

The amount of the free fatty acid is preferably from 0.01 to 0.7% by mass, particularly preferably from 0.05 to 0.5%. 0.7
If the amount is too large, the charging member such as a carrier and a developing roll is contaminated. Too little, rather, tends to increase blade wear and may shorten the life of the cleaning blade.

ESCA Measurement Machine The toner of the present invention has a BET specific surface area of 1.3 to 1.9 m.
It is preferably ² / g. Particularly preferred is 1.4.
Ｍ1.8 m ² / g.

The surface abundance of silicon atoms measured by ESCA was 6 to 12% by area, and the surface abundance of titanium element was 0.5% by area.
Preferably, the content of carbon atoms is 50 to 75 area%. If the BET specific surface area is too small, the fluidity is poor. If the BET specific surface area is too large, the variation in the charge amount due to the burying of the external additive tends to increase. The surface abundance of silicon atoms measured by ESCA was 6 to 12% by area, the surface abundance of titanium element was 0.5 to 4% by area, and the abundance of carbon atoms was 50%.
If it is in the region of about 75% by area, moisture absorption under high temperature and high humidity is small, and increase in charge amount under low temperature and low humidity is small, and a stable image can be obtained.

The ESCA measurement was performed using an ESCA- manufactured by Shimadzu Corporation.
Using 1000, the area ratio occupied by each element was determined from the relative intensity ratio of carbon, oxygen, silicon, and titanium atoms.

Cleaning Conditions In order to illustrate and explain the structure of the cleaning mechanism in the present invention, a typical example is shown in FIG. Reference numeral 1 denotes an elastic blade which is in contact with the latent image forming body 2 while being held by the holder 3 while a certain contact pressure is applied. In FIG. 1, reference numeral 4 denotes a member for applying the contact pressure.

The latent image forming member 2 is a photosensitive member in the electrophotographic system, and is most often formed on a drum-shaped support. In FIG. 1, the arrow is the traveling direction. Also, 6
Reference numeral denotes a guide plate for guiding the toner on the latent image forming body 2 scraped off by the elastic blade to the waste toner transport unit 5. Since the guide plate 6 is thin and soft, the toner adhering to the latent image forming body once passes under it and is scraped off by the elastic blade. Reference numeral 7 denotes an outer wall of the cleaning mechanism.

FIG. 2 shows a situation where the toner on the latent image forming body 2 is scraped off by the elastic blade 1.

FIG. 3 is a view for explaining the intersection angle φ between the holder 3 of the elastic blade 1 and the latent image forming body 2. As shown in FIG. That is, when the intersection angle φ is less than 90 °, the extension line is extended in the direction (Y-Y) in which the elastic blade of the holder is supported, and the intersection angle φ reaches the surface of the latent image forming body at the position where the surface reaches the latent image forming surface. Tangent (X
−X), the angle between the tangent and the extension is 9
It means that it is less than 0 °.

If this angle is 90 ° or more, it is necessary to secure sufficient cleaning properties.
That is, the toner produced by the polymerization method has a problem of slipping through the blade and contaminating the image. Although there is no particular lower limit angle, it is preferably 15 ° or more in terms of cleaning power. Further, a preferable range of the angle is 20 to 90 °, more preferably 25 to 80 °.

Further, as the material of the elastic blade used in the present invention, urethane rubber, silicone rubber, fluorine rubber, chloroprene rubber, butadiene rubber and the like can be used. Among them, urethane rubber-based materials are preferred. Particularly, as described in JP-A-59-30574, a polycaprolactone ester containing a caprolactone ester component of 30% by mass or more and having an average molecular weight of 1,000 to 4,000 is mixed with a polyisocyanate. Urethane rubber obtained by reaction curing is preferred.

The average molecular weight is defined as the amount of potassium hydroxide that neutralizes acetic acid produced when acetylation reaction is performed on polycaprolactone ester by using an acetylating reagent consisting of acetic anhydride and pyridine to determine the amount of terminal OH. The group was quantified and the number average molecular weight was calculated.

The general formula of the polycaprolactone ester preferably used in the present invention can be shown below.

HO-[-X _1- ] _m -R-[-X ₂ ] _n -OH Here, X ₁ and X ₂ are cleavage residues of a caprolactone ring, and may be the same or different from each other. Often, the sum of m and n is in the range of 2 to 35 and m: n = 3: 1 to 1: 3. R is a linking group of X ₁ and X ₂ having 300 carbon atoms.
These are the following divalent organic groups.

The compound represented by the above general formula has an average molecular weight of 1,000 to 4,000, and the content of the caprolactone ester component is 30% by mass or more.

In order to produce this polycaprolactone ester, the same or different caprolactone compounds 2
One mole of the polymerization initiator is added to 35 moles,
The polycaprolactone ester having an average molecular weight of 1,000 to 4,000 is obtained by ring-opening addition polymerization at 0 to 300 ° C. Examples of the polymerization initiator include -OH group, -N
An organic compound having two or more active hydrogens such as an H ₂ group or a —SH group can be given.

The caprolactone compound for forming the caprolactone ring-cleavable residue of the above general formula is a compound having a 3 to 7-membered ring and having 6 carbon atoms. Those to which a lower alkyl group such as a methyl group or an ethyl group is bonded are also included.

Specific examples are shown below.

[0128]

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[0129]

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Examples of the polymerization initiator for forming the linking group R in the above general formula include the following compound examples.

[0131]

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[0132]

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[0133]

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The following commercially available polycaprolactone esters are advantageously used for the cleaning blade according to the present invention.

"NIAXPCP 0240" (manufactured by Union Carbide) "CATA 220" (manufactured by Rapolde) "ODX 640" (manufactured by Dainippon Ink and Chemicals) It reacts to form urethane rubber, which is the material of the cleaning blade according to the present invention. Here, as the polyisocyanate, for example, the following can be mentioned as preferable ones.

[0136]

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[0137]

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[0138]

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[0139]

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[0140]

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[0141] Specific examples of the curing agent include the following.

[0142]

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[0143]

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As a method for producing a cleaning blade composed of the above polycaprolactone ester, etc.,
Although not particularly limited, for example, the following methods can be mentioned.

That is, the dehydrated polycaprolactone ester and polyisocyanate are mixed and reacted at a temperature of 70 to 150 ° C. for 10 to 120 minutes to prepare a urethane prepolymer. And a liquid rubber composition by adding a curing agent in a ratio such that the ratio of the number of moles of isocyanate groups to the number of moles of hydroxyl groups and / or amino groups by the polyester and the curing agent becomes 1.00 to 1.30. Making,
This rubber composition is poured into a centrifugal casting machine kept at a temperature of 140 ° C., for example. Next, the film is stretched to a uniform thickness on the inner surface of the rotor by the centrifugal force rotated at a high speed to form a cylindrical film. Thereafter, a cross-linking reaction by the curing agent proceeds and is solidified to form a urethane rubber.

In the present invention, the elastic blade preferably has a pressing force of 150 to 250 mN / cm during use, and has a physical property of hardness 6 measured according to JIS K 6301.
0 to 90 °, a tensile strength of 2500N / cm ² or more, impact resilience good 200 N / cm ² or more. Preferably, the tensile strength is 2500-8000 N / cm ² ,
More preferably 3000~6000N / cm ^2, the rebound resilience 200~1000N / cm ^2, more preferably 3
It is 00 to 900 N / cm ² .

Organic Photoconductor Next, the organic photoconductor of the present invention will be described.

In the present invention, the organic electrophotographic photoreceptor (organic photoreceptor) is constituted by giving an organic compound at least one of a charge generation function and a charge transport function which are indispensable for the constitution of the electrophotographic photoreceptor. Known organic electrophotographic photosensitive members, such as a photosensitive member composed of a known organic charge generating substance or an organic charge transporting substance, and a photosensitive member composed of a polymer complex having a charge generating function and a charge transporting function. Contains all body.

The constitution of the organic photoreceptor used in the present invention will be described below. Conductive Support As the conductive support used in the photoreceptor of the present invention, any of a sheet shape and a cylindrical shape may be used, but in order to design the image forming apparatus compactly, the conductive support of the cylindrical shape is used. Is more preferred.

The cylindrical conductive support of 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 or less. Conductive supports in the range 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 / plastic drum coated with a conductive substance can be used. The conductive support preferably has a specific resistance of 10 ³ Ωcm 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 the anodic oxidation treatment in sulfuric acid, the sulfuric acid concentration is preferably 100 to 200 g / L, the aluminum ion concentration is 1 to 10 g / L, the liquid temperature is about 20 ° C., and the applied voltage is preferably about 20 V. It is not limited. The average thickness of the anodic oxide coating is usually 2
0 μm or less, particularly preferably 10 μm or less.

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

In the present invention, in order to improve the adhesion between the conductive support and the photosensitive layer or to prevent charge injection from the support, an intermediate layer (undercoat) is provided between the support and the photosensitive layer. (Including a 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 undercoating 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 and a titanium coupling agent. The thickness of the intermediate layer using a curable metal resin is preferably 0.1 to 2 μm.

Photosensitive Layer 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. It is preferable to adopt a configuration in which the functions of the layers are separated into a charge generation layer (CGL) and a charge transport layer (CTL). 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. In the photoreceptor for negative charging, a charge generation layer (C
GL) and a charge transport layer (CTL) 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. Charge generation layer Charge generation layer: The charge generation layer contains a charge generation material (CGM). 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 for CGM in the charge generation layer, known resins can be used as the binder, but the most preferred resins are formal resins, butyral resins, silicone resins, silicone-modified butyral resins, and phenoxy resins. 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.

Charge Transport Layer 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 (CTM) 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, the CTM that can minimize the increase in residual potential due to repeated use has a high mobility and a characteristic in which the ionization potential difference with the CGM to be combined is 0.5 (eV) or less, and is 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. Resins, polycarbonate resins, silicone resins, melamine resins, and copolymer resins containing two or more of the repeating units of these resins;
A high-molecular organic semiconductor such as N-vinylcarbazole may be used.

The most preferred binder for these CTLs is a polycarbonate resin. Polycarbonate resins are most preferred for improving the dispersibility and electrophotographic properties of CTM. The ratio of the binder resin to the charge transport material is 1 to 100 parts by mass of the binder resin.
0 to 200 parts by mass is preferred. The thickness of the charge transport layer is preferably from 10 to 40 μm.

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

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. Toner Production Method The toner of the present invention is prepared by a suspension polymerization method or emulsion polymerization of a monomer in a liquid (in an aqueous medium) to which an emulsion of necessary additives is added.
Alternatively, fine resin particles are prepared by miniemulsion polymerization, the charge controllable resin particles of the present invention are added, and thereafter, an organic solvent, a flocculant such as salts are added, and the resin particles are aggregated and fused. It can be manufactured by a method.

<Suspension Polymerization Method> One example of a method for producing the toner of the present invention is as follows. A charge control resin is dissolved in a polymerizable monomer, and a colorant and, if necessary, a release agent. Various constituent materials such as a polymerization initiator are added, and the various constituent materials are dissolved or dispersed in the polymerizable monomer using a homogenizer, 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 stirring mechanism is moved to a reaction device (stirring device), which is a stirring blade described later, and heated to cause the polymerization reaction to proceed. After completion of the reaction, the toner of the present invention is prepared by removing the dispersion stabilizer, filtering, washing and drying. The “aqueous medium” in the present invention refers to a medium containing at least 50% by mass of water.

<Emulsion Polymerization Method> Further, as a method for producing the toner of the present invention, a method in which resin particles are prepared by salting out, aggregating, and fusing in an aqueous medium can also be mentioned. Although this method is not particularly limited, for example, JP-A-5-265252 and JP-A-6-329947
And Japanese Patent Application Laid-Open No. 9-15904.

That is, a method of salting out, aggregating, and fusing a plurality of fine particles composed of a resin and a colorant, or dispersed particles of a constituent material such as a resin particle and a colorant. After dispersing by using, a coagulant having a critical coagulation concentration or more is added and salting out.At the same time, the formed polymer itself is heat-fused at a temperature equal to or higher than the glass transition temperature to form a fused particle. When the target particle size is reached, a large amount of water is added to stop the particle size growth, and the particle surface is smoothed while heating and stirring to control the shape. By heating and drying in the state, 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.

<Composite Resin Particles Obtained by Multistage Polymerization> As typical examples of the method for producing a toner by an emulsion polymerization method, examples of composite resin particles obtained by a multistage polymerization method will be described. It is preferable that a region other than the outermost layer of the composite resin particles contains a release agent.

The toner manufacturing process mainly includes the following steps. 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 viewpoint 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-Step Polymerization Method> The two-step polymerization method comprises a central portion (nucleus) 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 composite 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 dissolved in an aqueous medium (for example, an aqueous surfactant solution). After the oil droplets are dispersed in the mixture, 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 L for obtaining a low molecular weight resin were added to the dispersion of the resin particles.
Polymerization treatment of monomer L in the presence of resin particles (second stage polymerization)
Is performed to form a coating layer made of a low molecular weight resin (monomer polymer) on the surface of the resin particles.

<Three-Step Polymerization Method> In the three-step polymerization method, 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 are used. 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 M in the aqueous medium is dispersed in oil droplets, and then the system is subjected to a polymerization treatment (second stage polymerization).
A coating layer (intermediate layer) made of a resin (polymer of monomer M) containing a release agent is formed on the surface of the resin particles (core particles) to form a composite resin particle (high molecular weight resin-intermediate molecular weight resin). )
A dispersion of is prepared.

Next, a polymerization initiator and a monomer L for obtaining a low molecular weight resin are added to the resulting dispersion of the composite resin particles, and the monomer L is subjected to a polymerization treatment in the presence of the composite resin particles. By performing (third stage polymerization), a coating layer made of a low molecular weight resin (polymer of monomer L) is formed on the surfaces 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.

In the present invention, the aqueous medium refers to 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.

As a polymerization method suitable for forming a resin particle or a coating layer containing a release agent, an aqueous medium obtained by dissolving a surfactant having a concentration equal to or lower than the critical micelle concentration is used.
A monomer solution in which the release agent is dissolved in the monomer is dispersed in oil droplets using mechanical energy to prepare a dispersion, and a water-soluble polymerization initiator is added to the obtained dispersion, A method in which radical polymerization is carried out in oil droplets (hereinafter, referred to as “mini-emulsion method” in the present invention) can be mentioned, and the effect of the present invention can be further exhibited, which is preferable. In the above method, an oil-soluble polymerization initiator may be used instead of or 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 or A sufficient amount of release agent can be introduced into the coating layer.

Here, the disperser for dispersing oil droplets by mechanical energy is not particularly limited. For example, a stirrer “CLEARMIX” equipped with a high-speed rotating rotor (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.

As other polymerization methods for forming resin particles or a coating layer containing a release agent, emulsion polymerization methods,
Known methods such as a suspension polymerization method and a seed polymerization method can also be employed. In addition, these polymerization methods are resin particles (core particles) or coating layers constituting the composite resin particles,
It can also be employed to obtain one that does not contain a release agent.

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

Also, 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. [Salt-out / fusion step (II)] This salt-out / fusion step (II)
Is an amorphous (non-spherical) by salting out / fusing the composite resin particles and the colorant particles obtained in the multi-stage polymerization step (I) (simultaneous salting out and fusion).
This is the step of obtaining the toner particles.

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.

For salting out / fusing the composite resin particles and the colorant particles, a salting-out agent (aggregating agent) having a critical aggregation concentration or more 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 preferred 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, and a filtration of the toner particles (cake-like) are performed. Washing treatment for removing extraneous substances such as surfactants and salting-out agents from the aggregates).

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

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

[0201] 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, 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 toner particles having been subjected to the drying treatment 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 of the present invention forms composite resin particles in the absence of a colorant, adds a dispersion of the colorant particles to a dispersion of the composite resin particles, and combines the composite resin particles with the colorant particles. It is preferably prepared by salting out / fusing.

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.

In addition, as a result of the reliable 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, since the surface properties of the obtained toner particles are uniform and the charge amount distribution is sharp, 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 component used in the toner manufacturing process will be described in detail. Polymerizable monomer As the polymerizable monomer for producing the resin (binder) used in the present invention, a hydrophobic monomer is an essential component, and a crosslinkable monomer is used as necessary. . 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. Further, 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, for example,
Styrene, o-methylstyrene, m-methylstyrene,
p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, p-ethylstyrene, p-n-butylstyrene, p-tert-butylstyrene, p-n-hexylstyrene, p-n- Styrene-based monomers such as octylstyrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, 2,4-dimethylstyrene, and 3,4-dichlorostyrene, and derivatives thereof. .

The acrylic monomers 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, ethyl β-hydroxyacrylate, propyl γ-aminoacrylate, stearyl methacrylate, methacryl Dimethylaminoethyl acrylate, diethylaminoethyl methacrylate and the like.

Examples of the vinyl ester monomer 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 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 (a) α, β-ethylenically unsaturated compound having a —COO group 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 thereof such as Na and Zn.

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 vinylpyridine,
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), 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 minimum 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 A known chain transfer agent can be used for the purpose of adjusting the molecular weight. The chain transfer agent is not particularly limited. For example, compounds having a mercapto group such as octyl mercaptan, dodecyl mercaptan, and tert-dodecyl mercaptan are 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 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.

[0231] 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 another step or another purpose.

Molecular weight distribution of resin particles and toner The molecular weight of the resin particles is from 100,000 to 1,000,000.
A resin containing at least a high molecular weight component having a peak or shoulder in the region of 00 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 G manufactured by Showa Denko KK
PC KF-801, 802, 803, 804, 80
5, 806, 807, and Tosoh TSKg
elG1000H, G2000H, G3000H, G4
000H, G5000H, G6000H, G7000
H, a combination of TSK guard columns, and the like. As the detector, a refractive index detector (IR detector) or a UV detector may be used. 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.

Coagulant The coagulant used in the present invention is preferably selected from metal salts.

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 a coagulant 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 using a metal salt so as to have a concentration equal to or higher than the critical aggregation concentration. At this time, of course, add the metal salt directly,
The addition 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.

Other Methods for Producing Colored Particles and Toner Next, as an example of a preferred production method of the present invention, an oil phase component is formed by dissolving or dispersing raw materials of a resin, a colorant, and a release agent in an organic solvent. And a method of granulating the oil phase component in an aqueous solvent will be described.

A step of dissolving or dispersing a resin, a charge control resin, a colorant, and a release agent in an organic solvent for dissolving a binder resin (binder resin) to prepare an oily component; And granulating the toner from a state in which the toner is dispersed in a medium.

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

As an organic solvent for solubilizing the binder resin, a general organic solvent is used. For example, toluene,
Hydrocarbons such as xylene and hexane; halogenated hydrocarbons such as methylene chloride, chloroform and dichloroethane; alcohols such as methanol and ethanol; ethers such as tetrahydrofuran; esters such as methyl acetate, ethyl acetate and butyl acetate; acetone and methyl ethyl ketone ,
Ketones such as cyclohexanone are mentioned, and among these, ethyl acetate, methyl ethyl ketone and the like are preferable in view 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 is to prepare particles by solidifying the oily component prepared in the above step from the state in which the oily component is dispersed in the aqueous medium. This is a step of drying this to obtain a toner.

As the method for producing particles, the binder resin,
A method in which a charge control resin, a coloring agent, a release agent, and a solution obtained by dissolving and dispersing other materials in a solvent are suspended and dispersed in an aqueous medium, and then the solvent is removed. The method of precipitating particles by adding, the binder resin, the charge control resin, a coloring agent, a release agent, a hot melt containing other materials is melted and dispersed in an aqueous medium, and then cooled to form particles. Examples of the method include a method of forming, a method of suspending and dispersing a mixed solution containing a polymerizable monomer, a colorant, a release agent, and other materials in an aqueous medium, and then polymerizing the monomer.

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.

Colorant The toner of the present invention is not particularly limited, including a method obtained by salting out / fusing the composite resin particles and the colorant particles, and a known colorant is widely used.

Examples of the colorant (colorant particles subjected to salting out / fusion with the composite resin particles) 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-described 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.

Known organic pigments and dyes can be used. Specific examples of organic pigments and dyes are shown below.

As the pigment for magenta or red,
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 the 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.

Examples of the dye include 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 of two or more as desired.
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.

As the silane coupling agent, for example,
Alkoxysilanes such as methyltrimethoxysilane, phenyltrimethoxysilane, methylphenyldimethoxysilane, diphenyldimethoxysilane, siloxanes such as hexamethyldisiloxane, γ-chloropropyltrimethoxysilane, vinyltrichlorosilane, vinyltrimethoxysilane, vinyltrimethoxysilane Examples include ethoxysilane, 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, 5B, which are commercially available under the trade name "Plenact" manufactured by Ajinomoto Co.
5, 138S, 238S, etc., commercial products A-
1, B-1, TOT, TST, TAA, TAT, TL
A, TOG, TBSTA, A-10, TBT, B-2,
B-4, B-7, B-10, TBSTA-400, TT
S, TOA-30, TSDMA, TTAB, TTOP and the like. As the aluminum coupling agent,
For example, (Plenact AL-M) manufactured by Ajinomoto Co. and the like can be mentioned.

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.

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

[0266] The surface-modified colorant particles are collected by filtration, and are dried after repeated washing and filtering with the same solvent.

Release Agent The toner used in the present invention is preferably a toner prepared by fusing resin particles containing a release agent in an aqueous medium. In this manner, the resin particles in which the release agent is encapsulated in the resin particles are salted out / fused with the colorant particles in an aqueous medium, whereby a toner in which the 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.

[0271]

Embedded image

[0272]

Embedded image

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

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

Range of Desirable Shape of Toner The shape factor of the toner of the present invention is represented by the following formula, and indicates the degree of roundness of toner particles.

Shape coefficient = ((maximum diameter / 2) ² × π) / projected area Here, the maximum diameter is defined as the 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.

In the toner of the present invention, when the particle diameter 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 histogram showing the number-based particle size distribution is obtained by plotting a natural logarithm lnD (D: particle size of individual toner particles) in 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.

By using the toner having the following shape and configuration, the presence of the external additive on the toner surface becomes uniform, the charge amount distribution becomes sharp, and high fluidity is obtained. As a result, excellent developability and fine line reproducibility, and stable cleaning properties can be formed for a longer period of time.

Further, the inventors of the present invention have focused on the minute shape of each toner particle, and as a result, the shape of the corner portion of the toner particle has been changed into a round shape inside the developing device, and the portion has become round. It was found that the burying of the external additive was promoted, and the change in the charge amount, the fluidity, and the cleaning property were reduced. In addition, when a charge is applied to the toner particles by triboelectric charging, it is presumed that the external additives are easily buried especially in the corner portions, and the charging of the toner particles is likely to be uneven, but this is also effectively prevented. it can.

That is, the toner of the present invention has a shape coefficient variation coefficient of 16% or less, a number variation coefficient in the number particle size distribution of 27% or less, and a shape coefficient of 1.0 to 1.0.
It is preferable to use a toner in which the ratio of the toner particles in the range of 6 is 65% by number or more.

In the toner of the present invention, the ratio of toner particles having no corners is 50% by number or more, the number variation coefficient in the number particle size distribution is 27% or less, and the shape factor is 1.0 to 1.0. The ratio of toner particles in the range of 6 is preferably at least 65% by number.

The toner of the present invention has a shape factor of 1.2 to 1.2.
It is preferable that the ratio of the toner particles in the range of 1.6 is 65% by number or more and the variation coefficient of the shape coefficient is 16% or less.

Furthermore, the particle diameter of the toner particles of the present invention
(Μm), the natural logarithm lnD is plotted on the horizontal axis, and the horizontal axis is the relative frequency 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 of 0.23. (M1) and the relative frequency (m) of the toner particles contained in the class having the highest frequency next to the mode.
It is preferable to use a toner whose sum (M) with 2) is 70% or more.

Developer 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 0.1 to 0.5 μm
And a magnetic one-component developer containing a certain amount of magnetic particles, and any of them can be used.

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.

Next, an image forming apparatus used in the image forming method of the present invention will be described.

FIG. 4 is a sectional view showing an example of the image forming apparatus of the present invention. Reference numeral 2 denotes a photoconductor drum as a latent image forming body, which is formed by forming an organic photoconductor (OPC) as a photoconductor layer on the outer peripheral surface of an aluminum drum base, and rotates at a predetermined speed in the direction of an arrow. I do.

In FIG. 4, based on information read by a document reading device (not shown),
Exposure light is emitted from. This is distributed by the polygon mirror 22 in the direction perpendicular to the paper surface of FIG. 4, and is radiated on the photoreceptor surface via the fθ lens 13 for correcting image distortion to form an electrostatic latent image. Photosensitive drum 2 as latent image forming body
Is uniformly charged in advance by the charger 15 and starts to rotate clockwise in synchronization with the timing of image exposure.

The electrostatic latent image on the surface of the photosensitive drum is
The developed image formed by the developing unit 6 is transferred to the transfer paper 18 which has been conveyed at a proper timing by the operation of the transfer unit 17. Further, the photosensitive drum 2 and the transfer paper 18 are separated by a separator (separation pole) 19, and the developed image is transferred and carried on the transfer paper 18, guided to the fixing device 10, and fixed.

The untransferred toner remaining on the photoreceptor surface is
It is cleaned by a cleaning device 11 of a cleaning blade type, and the residual charge is removed by a pre-charging exposure (PCL) 12, and is uniformly charged again by the charger 15 for the next image formation.

Toner recycling system The method for recycling the toner is not particularly limited. For example, a toner hopper, a developing device or a replenishing unit for collecting the toner collected in the cleaning unit by a transport conveyor or a transport screw. A method in which the toner is mixed with the intermediate chamber and supplied to the developing device can be used. Preferably, a method of directly returning the toner to the developing device or a method of mixing the replenishment toner and the recycled toner in the intermediate chamber and supplying the mixed toner can be used.

Next, FIG. 5 shows an example of a perspective configuration diagram of a toner recycling member. In this method, the recycled toner is directly returned to the developing device.

The untransferred toner collected by the cleaning blade 1 is collected in a toner recycle pipe 24 by a conveying screw in the toner cleaning device 11, and is returned to a developing device 16 from a receiving port 25 of the recycle pipe, and is again used as a developer. used.

FIG. 5 is also a perspective view of a process cartridge detachable from the image forming apparatus of the present invention. This figure 5
Although the photoconductor unit and the developer unit are separated from each other in order to make the perspective structure easy to understand, they can be removably mounted on the image forming apparatus as an integrated unit. In this case, the photosensitive drum, the developing device, the cleaning device, and the recycling member are integrated to form a process cartridge.

[0301] Further, the image forming apparatus may be configured such that a process cartridge including a photosensitive drum and at least one of a charger, a developing device, a cleaning device, and a recycling member is mounted.

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

Further, as described above, the cleaning blade 1 uses a rubber-like elastic body having a thickness of about 1 to 30 mm, and urethane rubber is most often used as a material. Since this is used by being pressed against the photoconductor, it is easy to conduct heat. In the present invention, it is desirable to provide a release mechanism and keep the photoconductor away from the photoconductor when the image forming operation is not performed.

The present invention can also be used in an image forming apparatus by electrophotography, particularly in an apparatus for forming an electrostatic latent image on a photoreceptor by a modulated beam modulated with digital image data from a computer or the like.

In recent years, in the field of electrophotography and the like in which an electrostatic latent image is formed on a photosensitive drum and this latent image is developed to obtain a visible image, it is easy to improve image quality, convert, edit, etc. Research and development of an image forming method employing a digital method capable of forming an image have been actively conducted.

As a scanning optical system that modulates light with a digital image signal from a computer or a copy original used in the image forming method and apparatus, an acousto-optic modulator is interposed in a laser optical system, and the light is modulated by the acousto-optic modulator. There is a device for modulating the light and a device for directly modulating the laser intensity using a semiconductor laser. These scanning optical systems form a dot-like image by spot exposure on a uniformly charged photoconductor.

The beam emitted from the above-mentioned scanning optical system has a round or elliptical luminance distribution approximating a normal distribution with a skirt spreading left and right. One or both of the scanning direction and the sub-scanning direction has an extremely narrow round or elliptical shape of 20 to 100 μm.

Fixing Apparatus The toner of the present invention is an image forming method including the step of fixing the transfer paper on which a toner image has been formed by passing the transfer paper between a heating roller and a pressure roller constituting a fixing device (the present invention). Image forming method).

FIG. 6 is a sectional view showing an example of a fixing device used in the image forming method using the toner of the present invention. The fixing device (fixing device) 10 shown in FIG. And a pressure roller 72 that comes into contact with the pressure roller 72. In FIG. 6, T is a toner image formed on the transfer paper (image forming support) 18.

[0310] The heating roller 70 has a coating layer 82 made of a fluororesin or an elastic body formed on the surface of a cored bar 81, and includes a heating member 75 made of a linear heater.

The core metal 81 is made of metal and has an inner diameter of 10 to 70 mm. The metal constituting the metal core 81 is not particularly limited, but examples thereof include metals such as iron, aluminum, and copper, and alloys thereof.

The thickness of the core bar 81 is set to 0.1 to 15 mm, and is determined in consideration of a balance between a demand for energy saving (thinning) and a strength (depending on a constituent material). For example,
In order to maintain a strength equivalent to that of a 0.57 mm iron core with an aluminum core, the wall thickness must be 0.8 mm.

Examples of the fluorine resin constituting the surface layer of the coating layer 82 include PTFE (polytetrafluoroethylene) and PFA (tetrafluoroethylene-perfluoroalkylvinyl ether copolymer).

The thickness of the surface layer of the coating layer 82 made of fluororesin is 10 to 500 μm, preferably 15 to 40 μm.
0 μm.

When the thickness of the surface layer of the coating layer 82 made of fluororesin is less than 10 μm, the function as the coating layer cannot be sufficiently exhibited, and the durability as a fixing device cannot be secured. On the other hand, if it exceeds 500 μm,
The thermal conductivity of the roller is reduced, and the melting of the toner becomes insufficient.

It is preferable to use silicone rubber and silicone sponge rubber having good heat resistance, such as LTV, RTV, and HTV, as the elastic body constituting the coating layer 82.

An elastic Asker C constituting the coating layer 82
The hardness is less than 80 °, preferably less than 60 °. The thickness of the covering layer 82 made of an elastic material is 0.1
３０30 mm, preferably 0.1-20 mm.

The elastic material Asker C constituting the coating layer 82
If the hardness exceeds 80 ° and the thickness of the coating layer 82 is less than 0.1 mm, the fixing nip cannot be increased, and the effect of soft fixing (for example, the smoothed interface Improvement effect of color reproducibility by toner layer)
Cannot be demonstrated.

As the heating member 75, a halogen heater can be suitably used. The pressure roller 72 is
A coating layer 84 made of an elastic material is formed on the surface of the core bar 83. The elastic body constituting the coating layer 84 is not particularly limited, and includes various soft rubbers such as urethane rubber and silicone rubber and sponge rubber. The silicone rubber exemplified as the material constituting the coating layer 82 can be used. And it is preferable to use silicone sponge rubber.

The elastic material Asker C constituting the coating layer 84
The hardness is less than 80 °, preferably less than 70 °, more preferably less than 60 °. The coating layer 84 has a thickness of 0.1 to 30 mm, preferably 0.1 to 2 mm.
0 mm.

An elastic Asker C constituting the coating layer 84
When the hardness exceeds 80 ° and when the thickness of the coating layer 84 is less than 0.1 mm, the nip for fixing cannot be increased, and the effect of soft fixing cannot be exhibited.

The material constituting the core bar 83 is not particularly limited, but may be a metal such as aluminum, iron, or copper or an alloy thereof.

The contact load (total load) between the heating roller 70 and the pressure roller 72 is usually 40 to 350 N, preferably 50 to 300 N, and more preferably 50 to 300 N.
２５０250N. This contact load is applied to the heating roller 1
It is defined in consideration of the strength of 0 (thickness of the core metal 75). For example, in the case of a heating roller having a core metal made of 0.3 mm iron, the heating roller is preferably set to 250 N or less.

Further, from the viewpoint of offset resistance and fixing property, the nip width is preferably 4 to 10 mm, and the surface pressure of the nip is 0.6 × 10 ^{5 to} 1.5 × 1.
It is preferably 0 ⁵ Pa.

An example of the fixing conditions by the fixing device shown in FIG. 6 is as follows. Fixing temperature (surface temperature of heating roller 70)
Is 150 to 210 ° C., and the fixing linear velocity is 80 to 640 m.
m / sec.

The fixing device used in the present invention may be provided with a cleaning mechanism as needed. In this case, as a method of supplying the silicone oil to the upper roller (heating roller) of the fixing unit, a method of supplying and cleaning with a pad, a roller, a web, or the like impregnated with the silicone oil can be used.

As the silicone oil, those having high heat resistance are used, and polydimethyl silicone, polyphenylmethyl silicone, polydiphenyl silicone and the like are used. Since those having a low viscosity have a large outflow during use, those having a viscosity at 20 ° C. of 1 to 100 Pa · s are preferably used.

However, the effect of the present invention is particularly remarkably exhibited when an image is formed by a fixing device that does not supply silicone oil or that supplies a very small amount of silicone oil. Therefore, even when the silicone oil is supplied, the supply amount is preferably 2 mg or less per A4 sheet.

By setting the supply amount of the silicone oil to 2 mg or less per A4 sheet, the amount of the silicone oil adhering to the transfer paper (image support) after fixing is reduced, and a ballpoint pen is formed by the silicone oil adhering to the transfer paper. There is no difficulty in writing with an oil-based pen, etc., and the writing performance is not impaired.

Further, it is possible to avoid problems such as deterioration of the offset resistance with time due to deterioration of the silicone oil, and contamination of the optical system and the strip electrode by the silicone oil.

Here, the supply amount of the silicone oil was adjusted by transferring the transfer paper (A) to a fixing device (between rollers) heated to a predetermined temperature.
100 sheets of 4 size white paper) are continuously passed, and the mass change (Δw) of the fixing device before and after the paper passing is measured and calculated (Δw / 100).

[0332]

Next, embodiments and effects of the present invention will be described with reference to examples. In the description, “parts” means “parts by mass”.

Abrasive external additive <Inorganic / organic composite fine particle preparation example 1> Average particle size 1.2 μm
m styrene / acrylic organic fine particles (glass transition point 95
Temperature) 100 g of titanium oxide particles whose primary particle diameter is 30 nm and whose surface is treated with tin oxide (trade name: ET-300W
(Ishihara Sangyo Co., Ltd.) was added and mixed with a turbula mixer for 40 minutes, followed by mixing with a vibration mill for 60 minutes.
Then, a powder surface reformer Hybridizer (manufactured by Nara Machinery Co., Ltd.) was used under conditions of a peripheral speed of 80 m / sec and 90 ° C.
After that, the inorganic / organic composite fine particles having titanium oxide fixed on the surface of the organic fine particles were prepared. This is designated as “inorganic / organic composite fine particles 1”.

The inorganic / organic composite fine particles have a circularity coefficient of 0.1.
985, the sticking ratio was 53.4%.

<Preparation Examples of Inorganic / Organic Composite Fine Particles 2 to 4 and Comparative Inorganic / Organic Composite Fine Particles 1 to 2> In Preparation Example 1 of inorganic / organic composite fine particles, the particle size, glass transition point, The temperature, peripheral speed, and processing time of the hybridizer were appropriately selected, and the inorganic / organic composite fine particles 2 to 4 and the inorganic / organic composite fine particles 1 to 2 shown in Table 1 were compared.
Was prepared.

[0336]

[Table 1]

<Metal oxide> Strontium carbonate 600
g and 320 g of titanium oxide were wet-mixed in a ball mill for 8 hours and then filtered and dried. This mixture is treated with 50 N / cm ²
And calcined at a temperature of 1100 ° C. for 8 hours.

Thereafter, mechanical pulverization was performed to obtain a number average particle size of 0.7 μm.
m and a strontium titanate powder having a circularity coefficient of 0.954 were obtained.

Preparation Example of Hydrophobic Silica Hydrophobic Silica a1 Fumed silica having a primary particle diameter of 0.007 μm (100
20 parts by mass of dimethyldichlorosilane was sprayed while stirring at 8500 rpm in a nitrogen atmosphere while stirring at 8500 rpm in a vessel having a high-speed mixer, and stirring was further continued for 5 minutes. 200 ° C
For 3 hours under reflux. Thereafter, the mixture was cooled to room temperature to obtain hydrophobic silica a1.

Hydrophobic silica a2 In the preparation example of the hydrophobic silica a1, the primary particle diameter was 0.00
Primary particle size 0.0 instead of 7 μm fumed silica
A hydrophobic silica a2 was obtained in the same manner as the hydrophobic silica a1, except that octyltrimethoxysilane was used instead of dimethyldichlorosilane for the 12 μm fumed silica.

Hydrophobic silica a3 In the preparation example of the hydrophobic silica a1, the primary particle diameter was 0.00
Primary particle size 0.0 instead of 7 μm fumed silica
A hydrophobic silica a3 was obtained in the same manner as the hydrophobic silica a1, except that fumed silica of 16 μm was used.

Hydrophobic Silica b1 In the preparation example of the hydrophobic silica a1, the primary particle diameter was 0.00
Primary particle size 0.0 instead of 7 μm fumed silica
A hydrophobic silica b1 was obtained in the same manner as the hydrophobic silica a1, except that octyltrimethoxysilane was used instead of dimethyldichlorosilane for fumed silica of 33 μm.

Hydrophobic silica b2 In the preparation example of hydrophobic silica a1, the primary particle diameter was 0.00
Primary particle size 0.0 instead of 7 μm fumed silica
Except that hexamethyldisilazane was used instead of dimethyldichlorosilane for 30 μm fumed silica,
Hydrophobic silica b2 was obtained in the same manner as hydrophobic silica a1.

Hydrophobic silica b3 In the preparation example of hydrophobic silica a1, the primary particle diameter was 0.00
Primary particle size 0.0 instead of 7 μm fumed silica
Hydrophobic silica b3 was obtained in the same manner as for hydrophobic silica a1, except that dimethylsilicone oil was used instead of dimethyldichlorosilane for 70 μm fumed silica.

Preparation Example of Hydrophobic Titanium Oxide Hydrophobic Titanium Oxide c1 Five parts of titanium oxide (having a number average particle diameter of 0.030 μm) dried at 110 ° C. for 24 hours in a round bottom flask equipped with a magnetic stirrer and a trap. 150 parts of dehydrated toluene and 1.5 parts of normal butyltrimethoxysilane were added to anatase type titanium oxide), and 0.5 part of acetic acid was further added as a buffer. The resulting suspension was refluxed at 50-60 ° C. for 7 hours, cooled to room temperature, and then filtered by suction.

Subsequently, the residue was washed with toluene and heated at 110 ° C.
For 4 hours. Thereafter, the mixture was subjected to suction filtration, then suction filtration with ethanol, dried at 110 ° C. for 4 hours, and pulverized in an agate mortar to obtain a white powdery substance. The obtained white powdery substance is referred to as hydrophobic titanium oxide c1.

Hydrophobic titanium oxide c2 In the production of titanium oxide c1, the number average particle diameter was 0.03.
A titanium oxide having a number average particle size of 0.021 μm (rutile, anatase ratio of 10:90) was used in place of 0 μm anatase type titanium oxide, and isobutyltrimethoxysilane was used in place of normal butyltrimethoxysilane. Thus, hydrophobic titanium oxide c2 was obtained.

Hydrophobic titanium oxide d1 In the production of titanium oxide c1, the number average particle size was 0.03
A titanium oxide having a number average particle size of 0.092 μm (rutile, anatase ratio 60:40) was used in place of 0 μm anatase-type titanium oxide, and octyltrimethoxysilane was used in place of normal butyltrimethoxysilane. As a result, a hydrophobic large particle diameter titanium oxide d1 was obtained.

In the production of hydrophobic titanium oxide d2 and titanium oxide c1, the number average particle diameter was 0.03.
A hydrophobic large particle size titanium oxide is prepared in the same manner except that rutile type titanium oxide having a number average particle size of 0.112 μm is used instead of 0 μm anatase type titanium oxide and hexyl trimethoxysilane is used instead of normal butyl trimethoxysilane. d2 was obtained.

Table 2 shows the physical properties of the hydrophobic silicas a1 to a3, b1 to b3 and the hydrophobic titaniums c1 to c3, d1 to d3.

[0351]

[Table 2]

Production Example of Fatty Acid Metal Salt Calcium Stearate First, the solid content concentration was 12.6% by mass, and the BET specific surface area was 10%.
A milk lime slurry of m ² / g was prepared. This lime milk slurry was wet-milled with 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 4
It was dehydrated to 0%.

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 at 100 ° C. under reduced pressure 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.

Example of Producing Resin Particles for Toner (Latex: 1HML) (1) Preparation of Core Particles (First Stage Polymerization) A 5000 ml separable flask equipped with a stirrer, a temperature sensor, a cooling pipe, and a nitrogen introducing device was placed in a flask. Anionic surfactant (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 monomer mixture comprising 05.6 g, 30.0 g of n-butyl acrylate, 6.4 g of methacrylic acid, and 5.6 g of n-octyl-3-mercaptopropionate was added to 19) in the above formulas 13 and 14). 72.0 g of the compound (hereinafter referred to as “exemplary compound (19)”) 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 completion of the dropping, polymerization (third-stage polymerization) was 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 and an intermediate layer composed of an intermediate molecular weight resin). And an outer layer made of a low-molecular-weight resin, and a dispersion of composite resin particles containing the exemplified compound (19) in the intermediate layer was obtained. This latex is referred to as “latex (1HML)”.

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.

[Coloring Particles 1 to 5 and Comparative Coloring Particle 1
~ 2] 57.0 g of sodium n-dodecyl sulfate was dissolved in 1700 ml of ion-exchanged water with stirring. While stirring this solution, 420.0 g of carbon black “REGAL 330” (manufactured by Cabot) is gradually added, and then colored by dispersing using “CLEARMIX” (manufactured by M-Technic). A dispersion of agent particles (hereinafter referred to as “colorant dispersion”) was prepared. When the particle size of the colorant particles in this colorant dispersion was measured using an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.), the weight average particle size was 112 nm.

A latex (1HML) 420.7 g (in terms of solid content), ion-exchanged water 900 g, and a colorant dispersion 166 g obtained in the production example of the resin particles for toner were charged with a temperature sensor, a cooling pipe, and nitrogen introduction. The mixture was placed in a reaction vessel equipped with a device, a stirrer, and a particle size and shape monitoring device (two-stage stirrer plate, the cross angle α of which was 25 °) and stirred.
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 system was heated to 90 ± 3 ° C. over 6 to 10 minutes (heating rate: 10 ° C./min).

[0366] In that state, "Coulter counter TA
-II ", and when the volume average particle size became 5.5 μm, sodium chloride 80.4 g
Was dissolved in 1000 ml of ion-exchanged water to stop the particle growth. Further, as an aging 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, washed repeatedly with ion-exchanged water, and then, using a flash jet drier, with an intake air temperature of 6.
Dry at 0 ° C. and then use a fluid bed drier at 60 ° C.
To obtain colored particles containing a release agent (exemplary compound (19)).

In the monitoring of the salting-out / fusion step and the shape control step, the coefficient of variation of the shape and the shape factor is controlled by controlling the number of revolutions of stirring and the heating time, and the variation coefficient of the particle size and the particle size distribution are controlled. Was arbitrarily adjusted to obtain colored particles 1 to 5 having the shape characteristics and particle size distribution characteristics shown in Table 3, and comparative colored particles 1 and 2.

[0368]

[Table 3]

The colored particles 1 to 5 obtained as described above
5, and the colored particles 1 to 2 for comparison, an abrasive external additive,
Hydrophobic silica a1 to a3, b1 to b3, hydrophobic titanium c
1 to c2 and d1 to d2 were added at the ratios shown in Tables 4 and 5, and a 10-liter Henschel mixer was mixed for 10 minutes while setting the peripheral speed of the rotor to 40 m / s. The shape and particle size of these colored particles do not change depending on the addition of the external additive.

[0370]

[Table 4]

[0371]

[Table 5]

Each of these toners contained 0.05 part of calcium stearate as a fatty acid metal salt.

Table 6 shows the results of counting the number of external additive particles present on the toner surface.

[0374]

[Table 6]

Production of Carrier Production of Ferrite Core Particles 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.
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 main-baked at 1200 ° C. for 3 hours to obtain ferrite core material particles having a resistance of 4.3 × 10 ⁸ .

Production of Coating Resin First, cyclohexyl methacrylate / cyclohexyl 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% by mass in an aqueous medium. A copolymer of methyl methacrylate (copolymerization ratio 5/5) was synthesized, 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.

Preparation of Developer Each of the colored particles to which the external additive was added was mixed with a carrier to prepare a developer having a toner concentration of 6% by mass.

Production of Photoreceptor Polyamide resin Amilan CM-8000 (manufactured by Toray Industries, Inc.) 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 titanyl phthalocyanine: Y-TiOPc was added thereto.
(Described in JP-A 64-17066, FIG. 1) 10 g was mixed and dispersed for 20 hours using a sand mill to obtain a coating liquid for the charge generation layer. 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, the surface of the photoreceptor sample (P1) was
The charge transport was carried out using a coating solution obtained by dissolving 30 g of TM (T-1) and 50 g of a polycarbonate resin Iupilon Z-800 (manufactured by Mitsubishi Gas Chemical Company) having a viscosity average molecular weight of 80,000 in 1,000 ml of 1,2-dichloroethane. After applying with a circular slide hopper on the layer,
After drying at 100 ° C. for 1 hour, an overcoat layer having a thickness of 5 μm was formed to obtain a photoreceptor (P2).

<Examples 1 to 10 and Comparative Examples 1 and 2> A commercially available digital copying machine Konica Satios 7020 equipped with a toner recycling system was loaded with a photoconductor (P
2) equipped with a modified machine (cleaning method using an elastic blade, the intersection angle φ between the holder and the latent image forming body is 25)
°) in a high temperature and high humidity environment (temperature 33 ° C, relative humidity 80
%), An actual image test was performed to continuously form 300,000 sheets of images with a pixel rate of 8%, and then the image density depended on the environment, halftone uniformity, fine dot dust, character collapse,
Fogging was evaluated.

In a toner recycling system, continuous printing of an image having a low pixel rate under a high-temperature and high-humidity environment is a severe condition for the following items because embedding of an external additive is promoted.

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 20 μm.

Slippage Toner was evaluated by the number of sheets that were detected as image stains by toner slipping onto the photosensitive member from the cleaning device on the white background of the image.

Image Blur A character image with a character size of 5 points is formed on the entire image.
Evaluation was made based on the number of sheets until an image is locally blurred or a portion where toner spreads around the image is detected.

Amount of Wear of Photoconductor The amount of wear of the photoconductor was calculated from the difference between the outer diameter of the photoconductor before actual shooting and the outer diameter of the photoconductor after actual shooting.

Lifetime of photoreceptor Evaluation was made based on the number of sheets when the fog density (relative density of the non-image area with respect to the transfer paper) when the exposure amount was maximized exceeded 0.01. The fog density was determined using a densitometer PDA-65.
(Manufactured by Konica Corporation).

Toner Filming of Photoreceptor The surface of the photoreceptor was visually evaluated every 10,000 sheets of printing.

Environment Dependence of Image Density The maximum image density of the solid image portion was measured with a Macbeth reflection densitometer. The image density difference 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 the difference is less than 0.05 and “○” when 0.05 to 0.1 ,
Those exceeding 0.1 were rated "x".

Uniformity of Halftone The uniformity of halftone was visually determined, and the uniformity of halftone image was evaluated. The rank was evaluated as follows.

Rank A: Uniform image without unevenness Rank B: Thin streak-like unevenness present Rank C: Several streak-like thin unevenness present Rank D: Several or more clear streak-like unevenness present Fine dots A 10% halftone image was formed on the entire surface of the image, and dust around the dots was observed with a loupe. An item with almost no detectable dust was marked with “◎”, slight dust was noted, but it was marked as “○” if it was not noticed unless watched closely, and “×” was marked as easily detectable with dust.

As the overall performance, “◎” is the best, and up to “△” is judged to be within the practicable range for the time being.
However, "x" has a problem in practical use.

Table 7 shows the results.

[0396]

[Table 7]

It can be seen that Examples 1 to 10 in the present invention are all within the practical range, while Comparative Examples 1 and 2 outside the present invention have practical problems.

[0398]

According to the present invention, there is little wear of the cleaning blade, no slip-through occurs for a long time, little wear of the photoreceptor, there is an effect of extending the life of the photoreceptor, no toner filming occurs, and environment dependency. Less, less decrease in halftone homogeneity due to embedding of toner external additive, stable image obtained, less dust around fine characters, easy to distinguish,
An image forming method and a toner can be provided.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a cleaning mechanism according to the present invention.

FIG. 2 is a diagram illustrating a situation where toner on a latent image forming body is scraped off by an elastic blade.

FIG. 3 is a diagram illustrating an intersection angle φ according to the present invention.

FIG. 4 is a cross-sectional configuration diagram illustrating an example of an image forming apparatus used in the image forming method of the present invention.

FIG. 5 is a perspective configuration diagram of a toner recycling member.

FIG. 6 is a cross-sectional view illustrating an example of a fixing device used in the image forming method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Elastic blade 2 Latent image forming body (photosensitive drum) 3 Holder 4 Member for applying contact pressure 5 Waste toner transport section 6 Guide plate 11 Semiconductor laser light source 12 Pre-charge exposure (PCL) 13 fθ lens 16 Developing device 17 Transfer unit 18 Transfer paper φ Cross angle

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) G03G 15/08 507 G03G 9/08 384 21/10 15/08 507D 21/00 318 326 (72) Inventor Sayuri Kushi Tokyo Inside Konica Corporation, 2970, Ishikawa-cho, Hachioji-shi, Tokyo Inventor Tomomi Oshiba Inside Konica Corporation, 2970, Ishikawa-cho, Hachioji-shi, Tokyo (72) Inventor Kenji Yamane 2970, Ishikawa-cho, Hachioji-shi, Tokyo Konica Corporation Terms (reference) 2H005 AA08 AA15 AB03 AB06 CA04 CA25 CB07 CB08 CB13 DA07 EA05 EA07 EA10 2H077 AA37 AC16 AD06 EA03 FA23 2H134 GA01 GB02 HD01 HD05 HD07 JA11 KG03 KG07

Claims (32)

[Claims] An image is formed by developing a latent image on a latent image forming body having an organic photosensitive layer using toner to form an image, and transferring the image to a transfer material. In an image forming method including a step of cleaning a residual image, the cleaning is performed by bringing a base portion of an elastic blade supported by a holder into contact with a latent image forming member, and forming the latent image forming member with the holder of the elastic blade. The crossing angle φ is less than 90 °, the toner contains 1.0 to 7.0% of particles of 3.17 μm or less on a number basis, and the number average particle size is 0.5 to 5.0.
An image forming method, which is a toner containing a μm abrasive external additive and a fatty acid metal salt. 2. The image forming method according to claim 1, wherein the cleaned toner is returned to a developing step and reused. 3. The toner contains 1 to 4.5% of particles of 3.17 μm or less on a number basis, and has a number average particle diameter of 0.5 to 3.
3. The image forming method according to claim 1, further comprising an abrasive external additive having a thickness of 0 [mu] m. 4. The toner according to claim 1, wherein the external additive is abrasive.
The image forming method according to claim 1, wherein the content is 2.0 parts by mass. 5. The method according to claim 1, wherein the toner has an abrasive external additive of 0.04 to
The image forming method according to claim 1, wherein the content is 1.0 part by mass. 6. The image forming method according to claim 1, wherein the circularity coefficient of the abrasive external additive of the toner is 0.950 to 0.998. 7. The external additive for abrasiveness of the toner contains, on the surface of the organic fine particles, inorganic / organic composite fine particles in which inorganic fine particles having a number average primary particle diameter of 5 to 100 nm are fixed to a fixing degree of 20 to 75%. The image forming method according to claim 1, wherein: 8. The image forming method according to claim 1, wherein the abrasive external additive of the toner is strontium titanate. 9. An external additive present on the surface of the toner having a particle size of 65 to 9 having a particle size of 0.005 to less than 0.025 μm
5% by number, less than 0.025 to 0.080 μm
An external abrasive additive having a number average particle size of 0.5 to 5.0 μm is added to a toner having a number average particle size of 0.5 to 5.0 μm to a toner of 0.3 to 35% by number and 0.080 to 0.500 μm adhered or fixed at 0.3 to 10% by number. 2. A toner according to claim 1, wherein
9. The image forming method according to any one of items 8 to 8. 10. An external additive of the toner comprising: a) silica having a number average particle size of 0.005 to 0.015 μm; b) silica having a number average particle size of 0.020 to 0.080 μm; c) number average particle. A toner having an externally added titanium oxide having a diameter of 0.015 to 0.070 μm and a titanium oxide having a number average particle diameter of 0.08 to 0.2 μm has a number average particle diameter of 0.5.
The image forming method according to any one of claims 1 to 9, wherein a toner containing an external abrasive additive having a thickness of from 5.0 to 5.0 µm is used. 11. A toner having a shape coefficient variation coefficient of 16
% Or less, and the number variation coefficient in the number particle size distribution is 2
The toner according to any one of claims 1 to 10, wherein a toner having a shape factor in a range of 1.0 to 1.6 and a proportion of toner particles of 65% by number or more is used. The image forming method as described in the above. 12. The toner has a ratio of toner particles having no corners of 50% by number or more, a number variation coefficient in a number particle size distribution of 27% or less, and a shape factor of 1.0 to 1.0.
The image forming method according to claim 1, wherein a ratio of the toner particles in the range of 6 is 65% by number or more. 13. The toner has a shape factor of 1.2 to 1.6.
11. The image forming apparatus according to claim 1, wherein the ratio of the toner particles in the range is 65% by number or more and the variation coefficient of the shape coefficient is 16% or less. 12. Method. 14. When the particle diameter of toner particles is D (μm), the natural logarithm lnD is plotted on the horizontal axis, and the horizontal axis is 0.2.
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 three intervals, and the toner particles included in the next most frequent class after the most frequent class The image forming method according to any one of claims 1 to 13, wherein a toner having a sum (M) of 70% or more with respect to a relative frequency (m2) is used. 15. The image forming method according to claim 1, wherein the toner is obtained by polymerizing at least a polymerizable monomer in an aqueous medium. 16. The image forming method according to claim 1, wherein the toner is obtained by aggregating and fusing at least resin particles in an aqueous medium. 17. An image is formed by developing a latent image on a latent image forming body provided with an organic photosensitive layer using toner to form an image, and transferring the image to a transfer material. In a toner used in an image forming method having a step of cleaning a residual image, the cleaning is performed by bringing a tip of an elastic blade supported by a holder into contact with a latent image forming body,
Intersection angle φ between the holder of the elastic blade and the latent image forming body
Is less than 90 °, and the toner is 3.17 μm on a number basis.
A toner comprising 1.0 to 7.0% of particles having a particle size of m or less, a number average particle diameter of 0.5 to 5.0 μm, and a metal salt of a fatty acid. 18. The toner according to claim 17, wherein the toner contains 4.5% or less of particles of 3.17 μm or less on a number basis.
The toner described in the above. 19. The toner according to claim 17, wherein the number average particle diameter of the abrasive external additive contained in the toner is 0.5 to 3.0 μm. 20. The toner according to claim 1, wherein the external additive is abrasive.
18 to 2.0 parts by mass.
20. The toner according to any one of 19. 21. A method in which the toner comprises 0.04 abrasive external additives.
18 to 1.0 part by mass.
21. The toner according to any one of 20. 22. The toner according to claim 17, wherein a circularity coefficient of the abrasive external additive of the toner is from 0.950 to 0.998. 23. An inorganic / organic composite fine particle in which the abrasive external additive of the toner is inorganic fine particles having a number average primary particle diameter of 5 to 100 nm fixed to the surface of the organic fine particles at a fixing degree of 20 to 75%. The toner according to any one of claims 17 to 22, characterized in that: 24. The toner according to claim 17, wherein the abrasive external additive of the toner is strontium titanate.
4. The toner according to any one of 3. 25. The toner according to claim 25, wherein the external additive present on the surface of the toner is from 0.005 to less than 0.025 μm.
5% by number, less than 0.025 to 0.080 μm
An external abrasive additive having a number average particle size of 0.5 to 5.0 μm is added to a toner having a number average particle size of 0.5 to 5.0 μm to a toner of 0.3 to 35% by number and 0.080 to 0.500 μm adhered or fixed at 0.3 to 10% by number. 18. A toner according to claim 17, wherein
25. The toner according to any one of items 24 to 24. 26. An external additive of the toner comprising: a) silica having a number average particle size of 0.005 to 0.015 μm; b) silica having a number average particle size of 0.020 to 0.080 μm; c) number average particle. A toner having an externally added titanium oxide having a diameter of 0.015 to 0.070 μm and a titanium oxide having a number average particle diameter of 0.08 to 0.2 μm has a number average particle diameter of 0.5.
The toner according to any one of claims 17 to 25, wherein a toner containing an external abrasive additive having a thickness of from 5.0 to 5.0 µm is used.
Item. 27. The toner according to claim 27, wherein the variation coefficient of the shape factor is 16
% Or less, and the number variation coefficient in the number particle size distribution is 2
The toner according to any one of claims 17 to 26, wherein a toner having a shape factor in a range of 1.0 to 1.6 and a toner particle ratio of 65% by number or more is used.
Item. 28. The toner, wherein the proportion of toner particles having no corners is 50% by number or more, the number variation coefficient in the number particle size distribution is 27% or less, and the shape factor is 1.0 to 1.
27. The toner according to claim 17, wherein the proportion of the toner particles in the range of 6 is 65% by number or more. 29. The toner has a shape factor of 1.2 to 1.6.
27. The toner particles according to claim 17, wherein the ratio of the toner particles in the range is 65% by number or more and the variation coefficient of the shape coefficient is 16% or less.
The toner according to Item. 30. Assuming that the particle size of the toner particles is D (μm), the natural logarithm lnD is plotted on the horizontal axis, and the horizontal axis is 0.2.
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 three intervals, and the toner particles included in the next most frequent class after the most frequent class The toner according to any one of claims 17 to 29, wherein a toner having a sum (M) of 70% or more with respect to the relative frequency (m2) is used. 31. The toner according to claim 17, wherein the toner is obtained by polymerizing at least a polymerizable monomer in an aqueous medium. 32. The toner according to claim 17, wherein the toner is obtained by aggregating and fusing at least resin particles in an aqueous medium.