JPH06110324A - Image forming method and device unit - Google Patents

Abstract

PURPOSE:To obtain a developed image with excellent developability, no or extremely low level fogging and and uniform image density by developing an electrostatic charge image with magnetic toner satisfying a specific condition. CONSTITUTION:The electrostatic charge image is developed by the magnetic toner satisfying the next conditions. That is, the diameter of a toner carrier is 7-15mm, magnetic flux density on the toner carrier at a developing part is >=400G, and the residual magnetization of the magnetic toner is 1.5-10enu/g. As to the number distribution of the electrostatically charged amount of the magnetic toner per the unit weight of the magnetic toner on the toner carrier; the position of maximum peak is 2-30muc/g(absolute value), and the component which has larger electrostatically charged amount than that of the maximum peak and of the same polarity is >=40 number %. The component which has larger electrostatically charged amount(absolute value) to an extent 10muc/g than the electrostatically charged amount for the maximum peak and of the same polarity from that of the maximum peak is >=30 number %, and the component whose electrostatically charged amount is >=40muc/g(absolute value) is >=10 number %.

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 and an apparatus unit used in electrophotography, electrostatic recording and the like.

[0002]

2. Description of the Related Art Conventionally, as an electrophotographic method, U.S. Pat. No. 2,297,691 and JP-B-42-23910 are known.
Although many methods are known as described in JP-B No. 43-24748 and Japanese Patent Publication No. 43-24748, generally, a photoconductive substance is used and an electric latent image is formed on a photoreceptor by various means. And then developing the latent image with toner,
After transferring the toner image to a transfer material such as paper, if necessary,
The toner is fixed by heat, pressure, heat and pressure, or solvent vapor to obtain a copy, and the toner remaining on the photoreceptor without being transferred is cleaned by various methods, and the above steps are repeated.

In recent years, such a copying apparatus has begun to be used not only as a general-purpose copying machine for copying original documents but also as a printer as an output of a computer or a personal copy for individuals. .

[0004] Therefore, smaller size, lighter weight, higher speed, and higher reliability have been rigorously pursued, and machines have come to be composed of simpler elements in various respects. As a result, the performance required for the toner has become higher, and if the improvement in the performance of the toner cannot be achieved, a better machine cannot be established.

That is, in order to achieve miniaturization, it is an essential requirement to reduce the diameters of the latent image carrier, the toner carrier and the like used therein in the image forming process. Therefore, the curvatures of the latent image carrier and the toner carrier become large, and the developing area becomes extremely narrow in the developing section. Under such conditions, good development cannot be achieved unless the toner used is magnetically or electrostatically controlled. In other words, even if there are few opportunities for triboelectrification, if they are uniformly charged and cannot respond sufficiently even in a weak magnetic field, fog or reversal fog may occur, or irregular image density unevenness may occur. become.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming method and an apparatus unit which solves the above problems.

An object of the present invention is to provide an image forming method and an apparatus unit which are excellent in developability, have no or very little fog, and provide a developed image having a uniform image density.

An object of the present invention is to provide an image forming method using a highly miniaturized image forming apparatus.

An object of the present invention is to provide a miniaturized device unit that constitutes an image forming apparatus.

[0010]

SUMMARY OF THE INVENTION According to the present invention, a latent image carrier for holding an electrostatic image and a toner carrier having a magnetic toner on its surface and having a magnetism generating means inside are provided in a developing section. A magnetic toner layer is formed on a toner carrier and conveyed to a developing unit with a certain gap provided, and an electrostatic charge image is transferred onto the magnetic toner while applying a bias between the toner carrier and the latent image carrier. In the image forming method of developing with, the diameter of the toner carrier is 7 to 15 mm, the magnetic flux density on the toner carrier in the developing section is 400 G or more,
The residual magnetization of the magnetic toner is 1.5 to 10 emu / g, and the maximum peak position is 2 to 30 μc / in the number distribution of the charge amount of the magnetic toner per unit weight of the magnetic toner on the toner carrier. g (absolute value), 40% by number or more of components having the same polarity and larger charge amount (absolute value) than the maximum peak charge amount, and the maximum peak charge amount (absolute value) to the maximum peak charge amount 10 with the same polarity than
Components with large charge (absolute value) up to μc / g are 3
An image forming method, wherein an electrostatic charge image is developed with a magnetic toner satisfying the condition that the content is 0 number% or more and the amount of charge is 40 μc / g or more (absolute value) is 10 number% or less. Regarding

Further, according to the present invention, a latent image holding member for holding an electrostatic charge image and a toner carrying member carrying magnetic toner on its surface and having a magnetism generating means inside are provided with a certain gap in the developing section. An image forming method in which an electrostatic charge image is developed with a magnetic toner by arranging it, forming a magnetic toner layer on a toner carrier, transporting it to a developing unit, and applying a bias between the toner carrier and the latent image carrier. , The latent image carrier has a diameter of 14 to 29 mm, and the residual magnetization of the magnetic toner is 1.
5 to 10 emu / g, and in the number distribution of the charge amount of the magnetic toner per unit weight of the magnetic toner on the toner carrier, the maximum peak position is 2 to 30 μc / g (absolute value), and the maximum There are 40% or more of components having the same polarity and larger charge amount (absolute value) than the peak charge amount, and from the maximum peak charge amount (absolute value) to 10 μc / g with the same polarity as the maximum peak charge amount. An electrostatic charge image with a magnetic toner satisfying the conditions that a component having a large charge amount (absolute value) is 30 number% or more and a component having a charge amount of 40 μc / g or more (absolute value) is 10 number% or less. And a method for forming an image.

Further, according to the present invention, a latent image holding member for holding an electrostatic charge image and a toner carrying member carrying magnetic toner on its surface and having a magnetism generating means inside are provided with a certain gap in the developing section. An image forming method in which an electrostatic charge image is developed with a magnetic toner by arranging it, forming a magnetic toner layer on a toner carrier, transporting it to a developing unit, and applying a bias between the toner carrier and the latent image carrier. In the above, the diameter of the toner carrier is 7 to 15 mm, the magnetic flux density on the toner carrier in the developing section is 400 G or more, and the diameter of the latent image carrier is 14 to 29 mm. The residual magnetization is 1.5 to 10 emu / g, and the maximum peak position is 2 to 30 μc / g in the distribution of the number of charges of the magnetic toner per unit weight of the magnetic toner on the toner carrier.
(Absolute value), 40% or more of components having the same polarity and larger charge amount (absolute value) than the maximum peak charge amount, and the maximum peak charge amount (absolute value) to the maximum peak charge amount Also satisfies the condition that 30% by number or more of components having the same polarity and a large charge amount (absolute value) up to 10 μc / g, and 10% or less of components having a charge amount of 40 μc / g or more (absolute value). The present invention relates to an image forming method characterized by developing an electrostatic charge image with the magnetic toner.

Furthermore, the present invention has a latent image carrier for holding an electrostatic charge image and a developing device for developing the electrostatic charge image, and the developing device is a toner for containing a magnetic toner. A container, a magnetic carrier in the toner container is carried from the toner container to a developing area facing the latent image carrier, and is carried. And a layer thickness regulating member for regulating the magnetic toner to a predetermined thickness to form a magnetic toner layer on the developer carrying member, and the diameter of the toner carrying member is 7
˜15 mm, the magnetic flux density on the toner carrier in the developing section is 400 G or higher, the diameter of the latent image carrier is 14 to 29 mm, and the residual magnetization of the magnetic toner is 1.
5 to 10 emu / g, and in the number distribution of the charge amount of the magnetic toner per unit weight of the magnetic toner on the toner carrier, the maximum peak position is 2 to 30 μc / g (absolute value), and the maximum There are 40% or more of components having the same polarity and larger charge amount (absolute value) than the peak charge amount, and from the maximum peak charge amount (absolute value) to 10 μc / g with the same polarity as the maximum peak charge amount. A magnetic toner having a triboelectrification characteristic satisfying the condition that a component having a large charge amount (absolute value) is 30 number% or more and a component having a charge amount of 40 μc / g or more (absolute value) is 10 number% or less. The developing device is held in a toner container, and the developing device has a terminal for applying a bias to the toner carrying member, and is integrally supported together with the electrostatic image holding member to form a unit, which is detachable from the main body of the device. The simple An apparatus unit, characterized in that to form a unit.

The structure of the present invention will be described with reference to FIG.

In FIG. 1, a latent image carrier (so-called photoconductor) such as a rotary drum in electrophotography, an insulator such as a rotary drum in electrostatic recording, a photosensitive paper in electrofax method, and a direct system electrostatic. 1 shows a latent image carrier such as an electrostatic recording paper in a recording method. An electrostatic charge image is formed on the surface of the latent image holding member 1 by a latent image forming process device or latent image forming process means (not shown), and the electrostatic image is rotated in the direction of the arrow.

In the developing device 2, 21 is a toner container (hopper) containing magnetic toner, 22 is a rotating cylinder as a toner carrier (hereinafter also referred to as a developing sleeve), and a magnetic field is provided inside the toner carrier. A magnetism generating means 23 such as a roller is built in.

In the drawing, the developing sleeve 22 has a substantially right half circumferential surface exposed in the hopper 21 and a substantially left half circumferential surface exposed to the outside of the hopper to support the bearing, and is rotationally driven in the direction of the arrow.
A doctor blade 24 as a toner layer regulating member is arranged on the upper surface of the sleeve 22 so as to approach the lower edge portion.
27 is a stirring member for the toner in the toner container.

The axis of the sleeve 22 is substantially parallel to the generatrix of the latent image carrier 1 and is closely opposed to the surface of the latent image carrier 1 with a small gap α.

The surface moving speeds (peripheral speeds) of the latent image carrier 1 and the sleeve 22 are substantially the same, or the peripheral speed of the sleeve 22 is slightly higher. A DC voltage and an AC voltage are superimposed and applied between the latent image holder 1 and the sleeve 22 by the alternating bias voltage applying means S ₀ and the DC bias voltage applying means S ₁ .

In the present invention, the diameter of the toner carrier is 7 to 15.
One of the characteristics is that the size is mm, and the downsizing of the developing device can be achieved. If it exceeds 15 mm, the developing device cannot be made compact, and the degree of contribution to downsizing of the image forming device is reduced. If it is less than 7 mm, it becomes difficult to uniformly triboelectrically charge the magnetic toner.

Further, the magnetic flux density in the toner carrier of the magnetic pole (developing pole, for example, S _{1 in} FIG. 1) near the developing section (A in FIG. 1) is 400 G or more (preferably 500 to 1000 G). Therefore, both image density and fogging can be achieved. The magnetic flux density referred to here is in the developing section, but when there is a gap in the developing section, it suffices if either one of the magnetic poles forming the gap is satisfied, preferably both. . If it is less than 400 G, the magnetic restraining force is weakened, pulling back of the excess toner onto the toner carrier becomes insufficient, and it tends to cause fogging and the toner consumption tends to increase. 1000G
Beyond, the magnetic binding force to the toner becomes stronger,
It is difficult for toner to fly to the latent image on the latent image carrier,
Image density tends to be difficult to obtain. The magnetic poles other than the developing pole are not particularly limited, and those having a total number of magnetic poles of 2 or more are used. Other magnetic poles are a carrier pole (for example, S ₂ in FIG. 1) and a seal pole (for example, S ₂ in FIG. 1).
N ₂ ), a cut pole (for example, N ₁ in FIG. ₁ ), a repelling pole, and the like.

In the present invention, the weight average diameter of the magnetic toner is 4
It is preferably from 10 μm, and it becomes easy to achieve good developability and low consumption. If the diameter of the toner carrier becomes smaller, the surface area of the toner carrier becomes smaller, and as a result, the chance of triboelectric charging of the toner decreases, so that good development cannot be performed unless the toner is rapidly and uniformly charged. When the weight average particle diameter is less than 4 μm, the surface area per unit weight becomes large, so that excessive charging easily occurs and fogging easily occurs, which makes it difficult to control. On the contrary, when the weight average particle diameter exceeds 10 μm, the surface area per unit weight becomes small, so that the charging tends to become non-uniform and the concentration tends to be difficult to obtain. Further, when the toner consumption increases, it is necessary to increase the size of the hopper, which is disadvantageous for downsizing the developing device. Since the magnetic toner used in the present invention consumes a small amount, it is possible to achieve a sufficient number of copies and prints even if the hopper is made small.

Further, the magnetic toner used in the present invention is 1
Remanent magnetization of 1.5 to 10 measured at 0 k Oersted
It is characterized by being emu / g, and both image quality and reversal fog can be achieved. When the diameter of the toner carrier becomes smaller, the curvature of the toner carrier in the developing unit increases and the range in which the magnetic field-influenced force in the developing region weakens expands, so that the toner itself needs to correspond to the magnetic field. When the remanent magnetization exceeds 10 emu / g, the magnetic field is greatly affected, the toner agglomeration is less likely to be loosened, and scattering and tail tailing are likely to occur, leading to deterioration in image quality. When the remanent magnetization is less than 1.5 emu / g, the magnetic field is less likely to be affected, the toner is sufficiently pulled back onto the toner carrier, and reversal fogging is likely to occur.

The magnetic toner in the magnetic toner layer on the toner carrier must have a maximum peak position of 2 to 30 μc / g (absolute value) in the number distribution of the charge amount of the magnetic toner per unit weight. Is. The position of the maximum peak is preferably 4 to 25 μc / g, more preferably 5 to 20 μc / g.
μc / g is good.

When the magnetic toner on the toner carrier is triboelectrically charged to the positive polarity, the position of the maximum peak is preferably +4 to +20 μc / g, more preferably +5 to +15 μc / g. Is good. When the maximum peak position is less than | 2 | μc / g, sufficient development is not performed, and problems such as low image density, background fog, and irregular uneven density are likely to occur. Then, the larger the maximum peak position, the less likely these phenomena occur. ｜ 30 ｜
When it exceeds μc / g, the charge tends to be excessive, and the image density tends to be low and “roughness” tends to occur. If the maximum peak position is smaller as the upper limit value, charging stability under low humidity or during durability is easily obtained, and these phenomena are less likely to occur.

Further, it is characterized in that 40% by number or more of components are larger than the maximum peak value, and preferably 42% by number.
It is preferably at least 45% by number, more preferably at least 50% by number. When the content of the component larger than the maximum peak value is less than 40% by number, the component of the magnetic toner which is relatively insufficiently charged is increased and the fog is apt to occur.

Further, the content of the component having a large charge amount from the maximum peak value to an absolute value of | 10 | μc / g from the maximum peak value is 30% by number, preferably 32% by number. It is above, more preferably 35% by number or more, and particularly preferably 40% by number or more. If the component in this region is less than 30% by number, the component most suitable for development is insufficient in the magnetic toner, and a sufficient image density cannot be obtained or density unevenness easily occurs.

Further, it is characterized in that the component having an absolute value of | 40 | μc / g or more is 10% by number or less, preferably 8% by number or less, more preferably 5% by number or less. Particularly preferably, it is 3% by number or less. If it exceeds 10% by number, the excessively charged component increases and accumulates on the toner carrier to hinder the triboelectrification of other magnetic toners, which easily causes low image density or ghost, Property (a phenomenon in which the higher the potential on the latent image carrier is, the lower the density is).

On the other hand, the diameter of the latent image carrier is 14 to 29 mm.
In this case, downsizing of the image forming apparatus can be achieved. If the diameter exceeds 29 mm, it becomes difficult to make the image forming apparatus compact. Further, if the diameter is less than 14 mm, it becomes difficult to dispose a charging device, a developing device, a cleaner and the like around the latent image holding member in good balance. As the diameter of the latent image carrier becomes smaller, the curvature in the developing section becomes larger and the developing area becomes narrower, and the electric field and magnetic field areas affecting the toner also become narrower, which is the same as when the diameter of the toner carrier becomes smaller. In addition, the toner is required to have the above physical properties.

Further, the diameter of the latent image carrier is 14 to 29 m.
m, and the diameter of the toner carrier is 7 to 15 mm,
Although it is possible to further reduce the size of the image forming apparatus, the requirements for development become more stringent, and the characteristics of the toner work more effectively.

Further, when the developing area becomes narrow and the curvatures of the latent image holding member and the toner holding member become large, the toner on the toner holding member is not electrostatically and temporally controlled at the time of development, and driving is performed. It becomes easy to pick up unevenness of the gear pitch of the portion and the pitch of the toner carrier, and regular uneven density and fog unevenness easily occur according to the pitch.

The developing process used in the present invention will be described in more detail.

In FIG. 1, the substantially right half peripheral surface of the developing sleeve 22 is constantly in contact with the toner pool in the toner container 21, and the toner near the developing sleeve surface is on the developing sleeve surface of the magnetic field generating means 23 in the sleeve. Attached and held by magnetic force and / or electrostatic force. When the developing sleeve 22 is rotationally driven, the magnetic toner layer on the sleeve surface passes through the position of the doctor blade 24 and is layered as a thin magnetic toner T ₁ having a substantially uniform thickness at each portion. The charging of the magnetic toner is mainly performed by frictional contact between the sleeve surface and the magnetic toner in the toner pool in the vicinity of the rotation of the developing sleeve 22, and the magnetic toner thin layer surface on the developing sleeve 22 is rotated by the rotation of the developing sleeve. It rotates to the side of the latent image holding member 1 which does not exist, and passes through the developing area A which is the closest portion between the latent image holding member 1 and the developing sleeve 22. During this passage, the magnetic toner in the thin layer of the magnetic toner on the surface of the developing sleeve 22 flies by the direct current and the alternating electric field due to the direct current and the alternating voltage applied between the latent image carrier 1 and the developing sleeve 22, and the latent image in the developing area A It reciprocates between the surface of the image carrier 1 and the surface of the developing sleeve 22. Finally, the magnetic toner on the side of the developing sleeve 22 is selectively transferred and adhered to the surface of the latent image holding member 1 surface according to the potential pattern of the latent image, and the toner images T ₂ are sequentially formed.

The developing sleeve surface on which the magnetic toner is selectively consumed after passing through the developing area A is re-rotated to the toner reservoir of the hopper 21 to be re-supplied with the magnetic toner, and the developing area A is developed. The surface of the magnetic toner thin layer T _{1 of the} sleeve 22 is transferred and the developing process is repeated.

The doctor blade used in the present invention is
Either a metal blade (for example, 24 shown in FIG. 1) arranged with a certain gap from the sleeve or an elastic blade that abuts the sleeve surface with an elastic force can be used. Blades are preferably used.

As the elastic blade, silicone rubber,
A rubber elastic body such as urethane rubber or NBR; a synthetic resin elastic body such as polyethylene terephthalate; a metal elastic body such as stainless steel or steel can be used. Moreover, even those composites can be used. A rubber elastic body is preferable.

The material of the elastic blade has a great influence on the charging of the toner on the toner carrier. Therefore, an organic substance or an inorganic substance may be added, melt-mixed, or dispersed in the elastic body. For example, metal oxide, metal powder, ceramics, carbon allotrope, whiskers,
There are inorganic fibers, dyes, pigments, surfactants and the like. Furthermore,
For the purpose of controlling the chargeability of the toner, rubber, synthetic resin, or metal elastic body may be used in which a substance such as resin, rubber, metal oxide, or metal is attached so as to contact the sleeve contact portion. When durability is required for the elastic body and the toner carrier, it is preferable to bond the resin and rubber to the metal elastic body so as to contact the sleeve contact portion.

When the magnetic toner is negatively charged, urethane rubber, urethane resin, polyamide, nylon, or a positively chargeable toner is preferable. When the toner is positively charged, urethane rubber, urethane resin, silicone rubber, silicone resin, polyester resin, fluorine resin (for example, Teflon resin), polyimide resin, or a material that is easily negatively charged is preferable. If the sleeve contacting part is a molded body of resin, rubber, etc., in order to adjust the charging property of the toner, it contains metal oxides such as silica, alumina, titania, tin oxide, zirconia, zinc oxide, carbon black. It is also preferable to include a charge control agent generally used in toner.

In particular, when the diameter of the toner carrier becomes smaller and the surface area thereof becomes smaller, the chance of triboelectric charging of the toner decreases. Therefore, the elastic blade is preferable in order to rapidly and uniformly charge the toner.

The base portion, which is the upper side of the elastic blade, is fixedly held on the developer container side, and the lower side is flexed in the forward or reverse direction of the developing sleeve against the elasticity of the blade so that the inner surface of the blade is bent. (The outer surface side in the opposite direction) is brought into contact with the sleeve surface with an appropriate elastic pressure. An example of the image forming apparatus is shown in FIGS. According to such a device,
A thin and dense toner layer can be obtained more stably against environmental changes. The reason for this is not clear, but the toner environment is forcibly rubbed against the sleeve surface by the elastic blade as compared to a commonly used device in which a metallic blade is mounted at a certain distance from the sleeve. It is presumed that the charging is always performed in the same state regardless of the change in behavior due to the change.

The gap α between the latent image carrier and the toner carrier is
For example, it is set to 50 to 500 μm, and when a magnetic blade is used as the doctor blade, the gap between the magnetic blade and the toner carrier is preferably set to 50 to 400 μm.

The thickness of the magnetic toner layer on the toner carrier is
It is most preferable that the gap is smaller than the gap α between the latent image carrier and the toner carrier, but in some cases, a part of many ears of the magnetic toner forming the magnetic toner layer is magnetic enough to contact the latent image carrier. You may regulate the layer thickness of a toner layer.

Further, the sleeve is 10 for the latent image carrier.
It is rotated at a peripheral speed of 0 to 200%. The alternating bias voltage is 0.1 kV or more in peak-to-peak, preferably 0.2 to 3.0 kV, more preferably 0.3 to 2.0 kV.
Good to use with V. The alternating bias frequency is 1.0 to
It is used at 5.0 kHz, preferably 1.0 to 3.0 kHz, and more preferably 1.5 to 3.0 kHz. A rectangular wave, a sine wave, a sawtooth wave, a triangular wave, or the like can be applied to the alternating bias waveform. Also, asymmetrical AC bias with different voltage and time, which are positive and reverse, can be used.

In the present invention, the sleeve is made of a material such as metal or ceramics, but aluminum, SUS or the like is preferable from the viewpoint of chargeability to the toner. The sleeve can be used as it is pulled out or cut, but in order to control the toner transporting property and the triboelectrification imparting property, it may be polished, roughened in the circumferential or longitudinal direction, or blasted. , Coating, etc. are performed. In the present invention, a blast treatment may be performed, and the regular particles and the irregular particles are used as the blasting agent, and they may be used alone or in combination, and may be overlaid.

Any abrasive grains can be used as the amorphous particles.

As the regular particles, for example, various hard spheres made of metal such as stainless steel, aluminum, steel, nickel and brass having a specific particle diameter or various hard spheres such as ceramic, plastic and glass beads can be used. it can. The regular particles are spherical or spheroidal particles having a curved surface and a major axis / minor axis day of 1 to 2 (preferably 1 to 1.5, more preferably 1 to 1.2). Is preferred. Therefore, the fixed particles used for the blast treatment on the surface of the developing sleeve preferably have a diameter (or major axis) of 20 to 250 μm. In the case of repeated hitting, the size of the regular blast particles is preferably larger than that of the irregular blast particles, particularly preferably 1 to 20 times, more preferably 1.5 to 9 times.

At the time of performing the over-strike treatment with the regular particles, at least one of the treatment time and the collision force of the treated particles is preferably smaller than that of the irregular particle blast.

Further, as the developing sleeve, it is also preferable that the sleeve surface has a coating layer containing conductive fine particles formed thereon.

The conductive fine particles are preferably carbon fine particles, or carbon fine particles and crystalline graphite, or crystalline graphite.

The crystalline graphite used in the present invention is roughly classified into natural graphite and artificial graphite. Artificial graphite is made by solidifying pitch coke with tar pitch or the like, firing it once at about 1,200 ° C, and then putting it in a graphitization furnace.
By processing at a high temperature of about 2,300 ° C, carbon crystals grow and change into graphite. Natural graphite is completely graphitized from the ground due to natural geothermal heat and underground high pressure for a long time. To do. These graphites have a wide range of industrial uses because they have various excellent properties. Graphite is a very soft and slippery crystalline mineral with dark gray or black luster. It is used for pencils and has heat resistance and chemical stability, so it is used as a lubricant, fire resistance, powder for electrical materials, etc. It is used in the form of solids and paints. The crystal structure includes hexagonal crystal and others belonging to the rhombohedral system, and has a completely layered structure. Regarding the electrical characteristics, free electrons are present between carbon-carbon bonds, making it a good conductor of electricity. The graphite used in the present invention may be natural or artificial.

The graphite used in the present invention preferably has a particle size of 0.5 μm to 10 μm.

The polymeric material forming the coating layer is, for example, styrene resin, vinyl resin, polyether sulfone resin, polycarbonate resin, polyphenylene oxide resin, polyamide resin, fluororesin, fibrin resin, acrylic resin. Use thermoplastic resin such as resin, thermosetting resin such as epoxy resin, polyester resin, alkyd resin, phenol resin, melamine resin, polyurethane resin, urea resin, silicone resin, polyimide resin or photocurable resin. You can Among them, those having releasability such as silicone resin and fluororesin, or those having excellent mechanical properties such as polyether sulfone, polycarbonate, polyphenylene oxide, polyamide, phenol resin, polyester, polyurethane and styrene resin are more preferable. preferable.

Conductive amorphous carbon is generally defined as "an aggregate of crystallites formed by burning or pyrolyzing a hydrocarbon or a compound containing carbon in a state where an air supply is insufficient". . In particular, it is widely used because it has excellent electric conductivity, and it can be filled with a polymer material to give conductivity, or it can obtain an arbitrary conductivity to some extent by controlling the amount added. The particle size of the conductive amorphous carbon used in the present invention is preferably 10 μm to 80 μm, more preferably 15 μm to 40 μm.

Amorphous silicon photoconductors and organic photoconductors are preferably used as the latent image carrier.

The organophotoreceptor used in the present invention may be a so-called single layer type in which the photosensitive layer contains a charge generating substance and a substance having a charge transporting property in the same layer, and the charge transporting layer and the charge generating layer are components. It may be a function-separated type photoconductor. A laminated type photoreceptor having a structure in which a charge generation layer and then a charge transport layer are laminated in this order on a conductive substrate is one of preferred examples.

The mode of the organic photoconductor used in the present invention will be described below.

Examples of the conductive substrate include metal such as aluminum or stainless steel, plastic having a coating layer made of aluminum alloy or indium oxide-tin oxide alloy, paper or plastic impregnated with conductive particles, and conductive polymer. A cylindrical cylinder such as plastic and a film are used.

On these conductive substrates, the adhesiveness of the photosensitive layer is improved, the coatability is improved, the substrate is protected, and the defects are covered on the substrate.
An undercoat layer may be provided for the purpose of improving the charge injection property from the substrate and protecting the photosensitive layer against electrical breakdown. The subbing layer is polyvinyl alcohol, poly-N-vinylimidazole, polyethylene oxide, ethyl cellulose, methyl cellulose, nitrocellulose, ethylene-acrylic acid copolymer, polyvinyl butyral, phenol resin, casein, polyamide, copolymerized nylon, glue,
It is formed of a material such as gelatin, polyurethane, aluminum oxide. The film thickness is usually 0.1 to 10 μm,
It is preferably about 0.1 to 3 μm.

The charge generation layer includes azo facial, phthalocyanine facial, indigo facial, perylene facial, polycyclic quinone facial, squarylium dye, pyrylium salt, thiopyrylium salt, triphenylmethane dye; selenium,
It is formed by dispersing a charge generating substance such as an inorganic substance such as amorphous silicon in a suitable binder and coating or by vapor deposition. The binder can be selected from a wide range of binder resins, for example, polycarbonate resin, polyester resin, polyvinyl butyral resin, polystyrene resin, acrylic resin, methacrylic resin, phenol resin, silicone resin, epoxy resin, vinyl acetate resin, etc. Is mentioned. The amount of the binder contained in the charge generation layer is 80% by weight.
Below, it is preferably selected from 0 to 40% by weight. The film thickness of the charge generation layer is preferably 5 μm or less, and particularly preferably 0.05 to 2 μm.

The charge transport layer has a function of receiving charge carriers from the charge generation layer in the presence of an electric field and transporting them. The charge transport layer is formed by dissolving a charge transport substance in a solvent together with a binder resin, if necessary, and applying it, and the film thickness thereof is 5 to 40 μm, preferably 10 to 3
It is 0 μm. As the charge transport substance, a polycyclic aromatic compound having a structure such as biphenylene, anthracene, pyrene, or phenanthrene in the main chain or side chain; indole,
Examples thereof include nitrogen-containing cyclic compounds such as carbazole, oxadiazole, and pyrazoline; hydrazone compounds; styrin compounds. As the binder resin in which these charge transporting substances are dispersed, resins such as polycarbonate resin, polyester resin, polymethacrylic acid ester, polystyrene resin, acrylic resin, polyamide resin; poly-N
Examples include organic photoconductive polymers such as vinylcarbazole and polyvinylanthracene.

Among these binder resins, polycarbonate resin, polyester resin, and acrylic resin are particularly good in the cleaning method in the case of the developing method according to the present invention, and have good cleaning property, poor cleaning, toner fusion to the photoreceptor, and Filming of the additive hardly occurs. The amount of the binder resin in the charge transport layer is preferably 40 to 70% by weight.

Further, it is also preferable that the outermost layer of the photoconductor contains a lubricious substance in terms of improvement of cleaning property and transfer property. A fluorine-based substance is preferable as the lubricating substance. Among them, the form containing the fluorine-based resin powder is particularly preferable.

Fluorine resin powders include tetrafluoroethylene resin, trifluoroethylene chloride resin, tetrafluoroethylene hexafluoropropylene resin, vinyl fluoride resin, vinylidene fluoride resin, and difluorodichloroethylene resin. One or more of these and copolymers are appropriately selected, and tetrafluoroethylene resin and vinylidene fluoride resin are particularly preferable. The molecular weight of the resin and the particle size of the powder can be appropriately selected and used from commercial grades, but low molecular weight grades and primary particles of 1 μm or less are particularly preferable.

The content of the fluororesin powder dispersed in the surface layer is appropriately 1 to 50% by weight, preferably 2 to 30% by weight, based on the solid content of the surface layer.

If the content is less than 1% by weight, the effect of modifying the surface layer by the fluororesin powder is not sufficient, while if it exceeds 50% by weight, the light transmittance is lowered and the mobility of the carrier is also lowered. .

When the fluororesin powder is contained, it is preferable to add a fluorograft polymer in order to improve the dispersibility in the photoconductor binder.

The fluorine-based graft polymer applicable to the present invention has a polymerizable functional group at one end and has a certain repeating unit and has a molecular weight of about 1000 to 10000 (hereinafter referred to as macromer) and a polymerizable monomer. It can be obtained by copolymerization with a monomer. The structure of the fluorine-based graft polymer is (i) in the case of copolymerization of a non-fluorine-based macromer synthesized from a non-fluorine-based polymerizable monomer and a fluorine-based polymerizable monomer, the trunk is a fluorine-based segment and the branches are non-fluorine-containing. System segment (ii) In the case of copolymerization of a fluorine-based macromer synthesized from a fluorine-based polymerizable monomer and a non-fluorine-based polymerizable monomer, the trunk is a non-fluorine segment and the branches are fluorine-based segments.

In the fluorine-based graft polymer, the fluorine-based segment and the non-fluorine-based segment are localized as described above, and the fluorine-based segment is a resin layer in which the fluorine-based segment is added to the fluorine-based resin powder. To
Each has a function-separated form oriented. In particular, since the fluorine-based segments are arranged continuously, the fluorine-based segments are highly densely and efficiently adsorbed to the fluorine-based resin powder, and the non-fluorine-based segments are oriented in the resin layer, resulting in the conventional dispersion. The effect of improving the dispersion stability of the fluororesin powder, which is not found in the agent, is exhibited.

In general, the fluororesin powder is present in the form of agglomerates of the order of several μ, but by using the fluorograft polymer of the present invention as a dispersant, primary particles up to 1 μm can be obtained. It is evenly dispersed.

In order to make maximum use of such a function separation effect, the molecular weight of the macromer should be 100 as described above.
It is necessary to adjust it to about 0 to 10,000.

That is, when the molecular weight is less than 1000, the length of the segment is too short, so that in the case of the fluorine-based segment, the adsorption efficiency to the fluorine-based resin powder decreases, and in the case of the non-fluorine-based segment. The orientation toward the surface layer resin layer is weakened, and in any case, the dispersion stability of the fluororesin powder is impaired.

On the other hand, if the molecular weight exceeds 10,000, the compatibility with the surface layer resin layer to be added decreases. This phenomenon is particularly remarkable in the fluorine-based segment, and since the segment has a coiled shape contracted in the resin layer, the number of adsorption active points for the fluorine-based resin powder is reduced and the dispersion stability is impaired.

Further, the molecular weight of the fluorine-based graft polymer itself has a great influence, and 10,000 to 100,000 is a preferable range. When the molecular weight is 10,000 or less, the dispersion stabilizing function is insufficiently expressed, and when the molecular weight is 100,000 or more, the compatibility with the surface layer resin layer to be added is reduced, and thus the dispersion stabilizing function is similarly not expressed.

The ratio of the fluorine-based segment in the fluorine-based graft polymer is preferably 5 to 90% by weight, and 1
0 to 70% by weight is more preferable.

When the ratio of the fluorine-based segment is less than 5% by weight, the dispersion stabilizing function of the fluorine-based resin powder cannot be sufficiently exhibited, and when it exceeds 90% by weight, the compatibility with the surface layer resin layer to be added is deteriorated. .

The amount of the fluorine-based graft polymer added is appropriately 0.1 to 30% by weight, preferably 1 to 20% by weight, based on the fluorine-based resin powder.

If the addition amount is less than 0.1% by weight, the dispersion stability effect of the fluorine-based resin powder is not sufficient, while if it exceeds 30% by weight, the fluorine-based graft polymer is adsorbed on the fluorine-based resin powder. In addition to existing, it becomes present inside the surface resin layer in a free state, and residual electric potential is accumulated when the electrophotographic process is repeatedly performed.

In order to extend the life of the photoconductor, it is preferable that the outermost layer of the photoconductor has a protective layer.

As the resin for the protective layer, polyester, polycarbonate, acrylic resin, epoxy resin, phenol resin, phosphazene resin, or a curing agent for these resins may be used alone or in combination of two or more, and exhibit a predetermined hardness. It is adjusted and used. Further, the thickness of the protective layer is 0 in order to avoid adverse effects such as increase in residual potential and decrease in sensitivity due to durable use due to provision of a layer in which charges do not move due to the constitution of the photosensitive layer. 0.1 to 6 μm is preferable, and 0.5 to 4 μm is more preferable.

The protective layer can be coated by spray coating, beam coating, or permeation coating by selecting a solvent.

Further, in order to adjust the electric resistance of the protective layer, the above-mentioned charge transport substance, metal, metal oxide particles or the like may be contained.

The metal oxide particles include zinc oxide, titanium oxide, tin oxide, antimony oxide, indium oxide,
Examples include ultrafine particles of bismuth oxide, tin oxide-coated titanium oxide, tin-coated indium oxide, antimony-coated tin oxide, zirconium oxide, and the like. These metal oxides may be used alone or in combination of two or more. When two or more kinds are mixed, they may be in the form of solid solution or fusion.

As a cleaning method, blade cleaning is preferable. For blade cleaning, urethane rubber, silicone rubber, or a resin having elasticity is used as a blade, or a chip-shaped resin is held at the tip of a blade such as metal in the forward or reverse direction with respect to the moving direction of the photoconductor. It is known as abutted or pressed. Preferably, the blade is brought into pressure contact in the direction opposite to the moving direction of the photoconductor. At this time, the contact pressure of the blade with respect to the photosensitive member is preferably 5 g / cm or more, more preferably 10 to 50 g / cm in terms of linear pressure. Further, the blade cleaning method may be combined with a mag brush cleaning method, a fur brush cleaning method, a roller cleaning method, or the like.

In the present invention, since the latent image carrier has a large curvature, it is preferable to use a blade in terms of cleaning property.

In the charging and transfer steps used in the present invention, there are a method of non-contact with a latent image carrier using a corona charger and a contact type method using a roller or the like, and either method is used. A contact type is preferably used for efficient uniform charging, simplification, and low ozone generation.

Further, an example of an image forming method having the contact charging / transferring method will be described with reference to the schematic diagram of FIG.

Reference numeral 601 denotes a rotary drum type electrostatic charge image carrier (hereinafter referred to as a photoconductor), which has a conductive base layer 601b such as aluminum and a photoconductive layer 602a formed on the outer surface thereof. It is a basic component layer,
It is rotated clockwise at a predetermined peripheral speed (process speed) in the drawing.

Reference numeral 602 denotes a charging roller, which has a core metal 602b at the center and a conductive elastic layer forming the outer periphery thereof as a basic structure. The charging roller 602 is the photoconductor 6
The surface 01 is pressed against the surface 01 with a pressing force, and is rotated by the rotation of the photoconductor 601. Reference numeral 603 is a charging bias current V ₂ for applying a voltage to the charging roller 602.
The surface of 01 is charged to a predetermined polarity and potential. Then, an electrostatic charge image is formed by image exposure 604, and the developing unit 6
The toner images are sequentially visualized by 05.

A bias V ₁ is applied from the bias applying means 613 to the developing sleeve constituting the developing means 605. The toner image formed on the latent image holding member by the development is electrostatically transferred to the transfer material 608 by the contact transfer means 606, and the toner image on the transfer material is heated and pressed and fixed by the heating and pressing means 611.

A transfer bias V ₃ is applied to the contact transfer means 606.
Is being applied.

In the image forming apparatus having such a contact charging / transferring system, as compared with the corona charging and the corona transfer, the photosensitive member can be uniformly charged and sufficiently transferred with a bias of a relatively low voltage. It is excellent in miniaturizing the discharger itself and suppressing corona discharge products such as ozone.

As other means, there are a method using a charging blade and a method using a conductive brush. These contact charging means have the effects of not requiring a high voltage and reducing the generation of ozone, but since the members are in direct contact with the photoconductor, the problem of toner fusion is likely to occur. It is most suitable for the present invention as a contact charging means. The present invention does not limit what kind of method and what kind of effect the applied contact charging means has, and any method of charging a member by directly contacting it with a photoconductor is applied to the present invention. It is possible.

A preferable process condition when the charging roller is used is that the contact pressure of the roller is 5 to 500 g / c.
In m, when a DC voltage superimposed with an AC voltage is used, AC voltage = 0.5 to 5 kVpp, AC frequency = 50
~ 5 kHz, DC voltage = ± 0.2 to ± 1.5 kV, and when using DC voltage, DC voltage = ± 0.2 to ±
It is 5 kV.

As the material of the charging roller and the charging blade, conductive rubber is preferable, and a releasing film may be provided on the surface thereof. As the releasable coating, nylon resin, PVDF (polyvinylidene fluoride), PVDC (polyvinylidene chloride), etc. can be applied.

In FIG. 6, reference numeral 606 is a transfer roller, which basically has a core metal 606b at the center and a conductive elastic layer 606a forming the outer periphery thereof. The transfer roller 606 is pressed against the surface of the photoconductor 601 with a pressing force, and is rotated at a constant speed or a peripheral speed different from the peripheral speed of the photoconductor 601. The transfer material 608 is conveyed between the photoconductor 601 and the transfer roller 606, and at the same time, a bias having a polarity opposite to that of the toner is applied from the transfer bias current 607 to the transfer roller 606 to transfer the toner image on the photoconductor 601. It is transferred to the surface side of the material 608.

As the material of the transfer rotary member applicable to the present invention, the same material as the charging roller can be used, and the preferable transfer process condition is that the contact pressure of the roller is 5 to 500 g / cm. , DC voltage is ± 0.2 ~
± 10 kV.

In the present invention, since the latent image carrier has a small diameter, it has a large curvature and a contact type is preferably used for uniform charging and good transfer.

Next, the transfer material 608 is conveyed to a fixing device 611 having a heating roller 611a having a halogen heater built therein and an elastic pressure roller 611b pressed against the heating roller 611a as a basic structure, and is transferred to the fixing device 611a and 611b.
The toner image is fixed by passing through the space. Alternatively, a method of fixing with a heater through a film may be used. Further, pressure fixing may be performed using a developer used for pressure fixing. After the transfer of the toner image, the surface of the photoconductor 601 is cleaned of adhering contaminants such as untransferred toner by a cleaning device equipped with an elastic cleaning blade that is pressed against the photoconductor 601 in the counter direction. It is made and is repeatedly imaged.

Examples of the contact type transfer device include a transfer roller as shown in FIG. 7 and a transfer belt as shown in FIG.

FIG. 7 is a schematic side view of the essential part of a typical image forming apparatus of this type. The apparatus shown in the drawing is a cylindrical latent image extending in the direction perpendicular to the plane of the drawing and rotating in the direction of arrow A. A holder (hereinafter, referred to as a photoconductor) 701 and a conductive transfer roller 702 that is in contact with the holder are provided.

The transfer roller 702 is composed of a cored bar 702a and a conductive elastic layer 702b, and the conductive elastic layer 702b is made of urethane or ethylene-containing conductive material such as carbon dispersed therein.
It is made of an elastic material such as propylene-diene terpolymer (EPDM) having a volume resistance of about 10 ⁶ to 10 ¹⁰ Ωcm. A bias is applied to the cored bar 702a by a constant voltage power source 708.

FIG. 8 shows a transfer belt to which the present invention is applied. The transfer belt 809 is supported and driven by the conductive roller 810. Pressurization of the transfer device is normally performed by the core metal 802a.
Alternatively, the pressure is applied to the end bearing of the core metal 810.

The contact pressure of the charger with respect to the photoconductor is 3 g / cm or more (preferably 5 g / c) as a linear pressure.
m or more) is preferable.

The linear pressure is calculated by the following formula. (Linear pressure) [g / cm] = (total pressure applied to transfer member)
[G] / (contact length) [cm] When the contact pressure is less than 3 g / cm, the transfer member is shaken,
Transfer failure due to insufficient transfer current occurs, which is not preferable.

13 and 14 show an apparatus unit of the present invention and an image forming apparatus incorporating the apparatus unit.

In this embodiment, an image forming unit (a developing device 132, a drum-shaped latent image carrier (photosensitive drum) 133, a cleaner 134 having a cleaning blade 134a, and a primary charger (charging roller) 135 are integrated. An electrophotographic image forming apparatus including a so-called cartridge 131 is exemplified.

In this apparatus, the image forming unit 1
When the magnetic toner 136 of the developing device 132 in 31 is used up, it is replaced with a new cartridge.

In this embodiment, the developing device 132 has the magnetic toner 137 in the toner container 136.
37, a predetermined electric field is formed between the photosensitive drum 133 and the toner carrier 138 by the bias from the bias applying means at the time of development, so that the photosensitive drum 133 and toner The distance to the carrier 138 is very important.

Further, another image forming apparatus of the present invention will be described with reference to FIG.

A bias V _{2 is} applied from the bias applying means 142.
Charging roller 135 which is a primary charger applied with
Then, the surface of the photoconductor 133 is negatively charged and exposed to light 14
4 forms an electrostatic charge image, and the electrostatic charge image is developed with the magnetic toner 137 of the developing device 132 including the urethane rubber elastic blade 9 installed in the counter direction and the developing sleeve 138 containing the magnet. . In the developing section, the conductive substrate of the photosensitive drum 133 and the developing sleeve 13
8, a bias V ₁ consisting of an alternating bias, a pulse bias and / or a DC bias is applied by the bias applying means 140. The transfer paper P is conveyed,
When it comes to the transfer portion, the bias V is applied from the bias applying means 143.
₃ is applied to the transfer paper P by the contact transfer means 143.
By charging the back surface (the surface opposite to the photosensitive drum side) of, the developed image (toner image) on the surface of the photosensitive drum 133 is electrostatically transferred onto the transfer paper P. The transfer paper P separated from the photosensitive drum 133 is fixed by a heating and pressure roller fixing device 145 to fix the toner image on the transfer paper P.

The magnetic toner remaining on the photosensitive drum after the transfer process is removed by the cleaning means 134 having the cleaning blade 134a. The photosensitive drum 133 after cleaning is erased by erase exposure 146,
The process starting from the charging process by the charging roller 135 is repeated again.

As the binder resin for the magnetic toner used in the present invention, the following binder resins can be used.

For example, homopolymers of styrene such as polystyrene, poly-p-chlorostyrene, polyvinyltoluene and the like and substitution products thereof; styrene-p-chlorostyrene copolymers, styrene-vinyltoluene copolymers, styrene-vinylnaphthalene. Copolymer, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-
Styrene such as vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer -Based copolymer; polyvinyl chloride, phenol resin, natural modified phenol resin, natural resin modified maleic acid resin, acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, polyurethane, polyamide resin, furan resin, epoxy resin , Xylene resin, polyvinyl butyral, terpene resin, coumarone indene resin, petroleum resin and the like can be used. Preferred binder materials include styrene copolymers and polyester resins.

Examples of the comonomer for the styrene monomer of the styrene type copolymer include acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate,
Dodecyl Acrylate, Octyl Acrylate, 2-Ethylhexyl Acrylate, Phenyl Acrylate, Methacrylic Acid, Methyl Methacrylate, Ethyl Methacrylate, Butyl Methacrylate, Octyl Methacrylate, Acrylonitrile, Methacrylonitrile, Acrylamide, etc. A monocarboxylic acid having a bond or a substituted product thereof; for example, a dicarboxylic acid having a double bond such as maleic acid, butyl maleate, methyl maleate, dimethyl maleate and the like; and a substituted product thereof; for example, vinyl chloride, vinyl acetate, Vinyl esters such as vinyl benzoate; ethylene-based olefins such as ethylene, propylene, butylene; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone; Chirueteru, vinyl ethyl ether, vinyl ethers such as vinyl isobutyl ether; vinyl monomers are used alone or two or more.

The styrene polymer or styrene copolymer may be crosslinked or may be a mixed resin.

As the crosslinking agent for the binder resin, a compound having two or more polymerizable double bonds may be mainly used. For example, aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene; eg ethylene. Carboxylic acid esters having two double bonds such as glycol diacrylate, ethylene glycol dimethacrylate and 1,3-butadiol dimethacrylate; divinyl compounds such as divinylaniline, divinyl ether, divinyl sulfide and divinyl sulfone; and 3
A compound having at least one vinyl group; is used alone or as a mixture.

In the bulk polymerization method, it is possible to obtain a low molecular weight polymer by polymerizing at a high temperature to accelerate the termination reaction rate, but it is difficult to control the reaction.
In the solution polymerization method, a low molecular weight polymer can be easily obtained under mild conditions by utilizing the difference in radical chain transfer depending on the solvent, and by adjusting the amount of the initiator and the reaction temperature. It is preferred when low molecular weight products are obtained in the composition.

As the solvent used in the solution polymerization, xylene, toluene, cumene, cellosolve acetate, isopropyl alcohol, benzene or the like can be used. In the case of a styrene monomer mixture, xylene, toluene or cumene are preferred. It is appropriately selected depending on the polymer to be polymerized.

The reaction temperature varies depending on the solvent used, the initiator and the polymer to be polymerized, but is 70 ° C to 23 ° C.
It is better to do it at 0 ° C. Solvent 100 in solution polymerization
It is preferable to carry out 30 to 400 parts by weight of monomer with respect to parts by weight.

Further, it is also preferable to mix another polymer in the solution at the end of the polymerization, and several polymers can be mixed well.

As the polymerization method for obtaining the high molecular weight component or gel component, the emulsion polymerization method or the suspension polymerization method is preferable.

Among them, the emulsion polymerization method is a method in which a monomer (monomer) almost insoluble in water is dispersed as small particles in an aqueous phase with an emulsifier, and polymerization is performed using a water-soluble polymerization initiator. . In this method, the heat of reaction can be easily adjusted, and the termination reaction rate is low because the phase in which the polymerization is performed (oil phase consisting of polymer and monomer) and the aqueous phase are different, resulting in a high polymerization rate. A high degree of polymerization can be obtained.
Further, the reason is that the polymerization process is relatively simple, and that the polymerization product is fine particles, so that it is easy to mix with a colorant, a charge control agent and other additives in the production of toner. Therefore, it is advantageous as a method for producing a binder resin for toner as compared with other methods.

However, the resulting polymer is likely to become impure due to the added emulsifier, and an operation such as salting out is required to take out the polymer, so suspension polymerization is a simple method.

In the suspension polymerization, 100 parts by weight or less of the monomer (preferably 1 part by weight) is added to 100 parts by weight of the aqueous solvent.
0 to 90 parts by weight) is preferable. As the dispersant that can be used, polyvinyl alcohol, partially saponified polyvinyl alcohol, calcium phosphate, etc. are used, which is an appropriate amount depending on the amount of the monomer to the aqueous solvent, but generally 0.05 to 1 per 100 parts by weight of the aqueous solvent. Used in parts by weight. The polymerization temperature is suitably 50 to 95 ° C., but it should be appropriately selected depending on the initiator used and the target polymer. As the initiator type, any initiator that is insoluble or hardly soluble in water can be used.

As the initiator to be used, t-butylperoxy-2-ethylhexanoate, cumylperpivalate, t-butylperoxylaurate, benzoyl peroxide, lauroyl peroxide, octanoyl peroxide, diester. -T-butyl peroxide, t
-Butyl cumyl peroxide, dicumyl peroxide, 2,2'-azobisisobutyronitrile, 2,2 '
-Azobis (2-methylbutyronitrile), 2,2'-
Azobis (2,4-dimethylvaleronitrile), 2,
2'-azobis (4-methoxy-2,4-dimethylvaleronitrile), 1,1-bis (t-butylperoxy)
3,3,5-Trimethylcyclohexane, 1,1-bis (t-butylperoxy) cyclohexane, 1,4-bis (t-butylperoxycarbonyl) cyclohexane, 2,2-bis (t-butylperoxy) Octane,
n-butyl 4,4-bis (t-butylperoxy) valerate, 2,2-bis (t-butylperoxy) butane, 1,3-bis (t-butylperoxy-isopropyl) benzene, 2,5 -Dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl-2,5
-Di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane,
Di-t-butyldiperoxyisophthalate, 2,2-
Bis (4,4-di-t-butylperoxycyclohexyl) propane, di-t-butylperoxy α-methylsuccinate, di-t-butylperoxydimethylglutarate, di-t-butylperoxyhexahydro Terephthalate, di-t-butylperoxyazelate, 2,
5-dimethyl-2,5-di (t-butylperoxy) hexane, diethylene glycol-bis (t-butylperoxycarbonate), di-t-butylperoxytrimethyl adipate, tris (t-butylperoxy) triazine, Examples thereof include vinyltris (t-butylperoxy) silane, and these can be used alone or in combination.

The amount used is 0.05 parts by weight or more (preferably 0.1 to 15 parts by weight) per 100 parts by weight of the monomer.

The composition of the polyester resin used in the present invention is as follows.

Examples of the dihydric alcohol component include ethene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol and 1,5-pentane. Diol, 1,6-hexanediol, neopentyl glycol, 2-ethyl-1,3-
Hexanediol, hydrogenated bisphenol A, or (A)
Bisphenol represented by the formula and derivatives thereof;

[0129]

[Outer 1] (In the formula, R is an ethylene or propylene group, and x, y
Are integers of 0 or more, and the average value of x + y is 0 to 10. ) Further, diols represented by the formula (B);

[0130]

[Outside 2] (In the formula, R ′ is —CH ₂ CH ₂ — or

[0131]

[Outside 3] x ′ and y ′ are integers of 0 or more, and the average value of x + y is 0 to 10. ) Is mentioned.

Examples of the divalent acid component include phthalic acid,
Benzene dicarboxylic acids such as terephthalic acid, isophthalic acid and phthalic anhydride, or their anhydrides, lower alkyl esters; alkyl dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, azelaic acid or their anhydrides, lower alkyl esters; n- Alkenyl succinic acids such as dodecenyl succinic acid and n-dodecyl succinic acid or alkyl succinic acids, or their anhydrides, lower alkyl esters; unsaturated dicarboxylic acids such as fumaric acid, maleic acid, citraconic acid, itaconic acid or their anhydrides, lower Examples thereof include dicarboxylic acids such as alkyl ester; and derivatives thereof.

Further, it is preferable to use a trivalent or higher valent alcohol component acting as a crosslinking component and a trivalent or higher valent acid component in combination.

As the polyhydric alcohol component having a valence of 3 or more,
For example, sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol,
1,2,4-butanetriol, 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,
3,5-trihydroxybenzene etc. are mentioned.

Examples of the trivalent or higher polycarboxylic acid component in the present invention include trimellitic acid, pyromellitic acid, 1,2,4-benzenetricarboxylic acid, 1,
2,5-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,
5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, tetra (methylenecarboxyl) methane, 1,2,7,8-
Octane tetracarboxylic acid, empol trimer acid, and their anhydrides, lower alkyl esters;

[0136]

[Outside 4] (Wherein X is an alkylene group or alkenylene group having 5 to 30 carbon atoms having at least one side chain having 3 or more carbon atoms), etc., and polycarboxylic acids such as their anhydrides and lower alkyl esters. Examples thereof include carboxylic acids and their derivatives.

The alcohol component used in the present invention is 40 to 60 mol%, preferably 45 to 55 mol.
%, 60-40 mol% as an acid component, preferably 5
It is preferably 5 to 45 mol%.

The polyvalent component having a valence of 3 or more is preferably 5 to 60 mol% of all the components.

A styrene-unsaturated carboxylic acid derivative copolymer, from the viewpoints of developing property, fixing property, durability and cleaning property,
Preferred are polyester resins, block copolymers and graft products thereof, and further mixtures of styrene copolymers and polyester resins.

In addition, it is preferable that the molecular weight distribution measured by GPL has a peak in a region of 10 ⁵ or more,
Further, it is preferable that the compound has a peak in the region of 3 × 10 ^{3 to} 5 × 10 ^{4 from} the viewpoint of fixability and durability.

Such a resin component can be obtained, for example, by the following method.

By applying solution polymerization, bulk polymerization, suspension polymerization, emulsion polymerization, block copolymerization, grafting, etc., a polymer (L) having a main peak in the molecular weight range of 3 × 10 ^{3 to} 5 × 10 ⁴ is obtained. A polymer having a main peak in the region of 10 ⁵ or more or a polymer (H) containing a gel component is formed. It can be obtained by blending these components during melt-kneading. The gel component can be partially or wholly cleaved during melt-kneading, and becomes a THF-soluble component to be measured by GPC as a component in a region of 10 ⁵ or more.

As a particularly preferred method, the polymer (L)
Alternatively, the polymer (H) is formed by solution polymerization, and at the end of the polymerization, the other is blended in a solvent, the other polymer is polymerized in the presence of one polymer, and the polymer (H) is suspended. A method of forming by polymerization and polymerizing the polymer (L) by solution polymerization in the presence of this polymer, a method of blending the polymer (H) in a solvent at the end of the solution polymerization, and the presence of the polymer (L) Then, there is a method in which the polymer (H) can be polymerized by suspension polymerization. By using these methods, a polymer in which a low molecular weight component and a high molecular weight component are uniformly mixed can be obtained.

Further, in the case of a positively chargeable toner, a styrene-acryl copolymer, a styrene-methacryl-acrylic copolymer, a styrene-methacryl-copolymer, a styrene-butadiene copolymer, and an acid value of 10 or less. Are preferred, and the block copolymers, graft products, and blend resins of these are preferred, and in the case of a negatively chargeable toner, styrene-acryl copolymer, styrene-methacryl-acryl copolymer, styrene-methacryl- From the viewpoint of developability, copolymers and copolymers thereof with maleic acid monoesters, polyester resins, and block copolymers, graft products and blend resins thereof are preferable.

The resin is preferably selected from the above-mentioned resins having good triboelectric chargeability from the viewpoint of developability since the surface area of the sleeve is small and the opportunity for imparting triboelectric charge is small.

Particularly, as the binder resin for the toner to be subjected to the pressure fixing method, low molecular weight polyethylene, low molecular weight polypropylene, ethylene-vinyl acetate copolymer, ethylene-acrylic acid ester copolymer, higher fatty acid, polyamide resin , And polyester resin. They are,
It is preferably used alone or as a mixture.

It is also preferable to include the following waxes in the toner from the viewpoint of improving the releasability from the fixing member during fixing and the fixing property.

Paraffin wax and its derivatives, montan wax and its derivatives, microcrystalline wax and its derivatives, Fischer-Tropsch wax and its derivatives, polyolefin wax and its derivatives, carnauba wax and its derivatives, etc. Includes block copolymers and graft modified products with vinyl monomers.

In addition, alcohols, fatty acids, acid amides,
Esters, ketones, hydrogenated castor oil and its derivatives, vegetable wax, animal wax, mineral wax, petrolactam and the like can also be used. In the present invention, rapid and uniform chargeability is required, and the above-mentioned ones are preferable from the viewpoint of developability.

Among them, the wax which is preferably used is a low molecular weight polyolefin obtained by radically polymerizing an olefin under high pressure or using a Ziegler catalyst, a by-product at this time, and a low molecular weight obtained by thermally decomposing a high molecular weight polyolefin. The waxes obtained from the distillation residue of hydrocarbons obtained by using a catalyst from a synthesis gas consisting of polyolefin, carbon monoxide, and hydrogen, or the synthetic hydrocarbons obtained by hydrogenating these are used as antioxidants. May be added. Alternatively, it is a linear alcohol, acid amide, ester, or montan derivative. Further, it is also preferable that impurities such as fatty acids have been removed in advance.

Particularly preferred are those obtained by polymerizing olefins such as ethylene with a Ziegler catalyst, by-products at this time, and hydrocarbons having a carbon number of several thousand, particularly up to about 1,000, such as Fischer-Tropsch wax. Things are good.

From these waxes, the wax was fractionated according to its molecular weight by using a press sweating method, a solvent method, a vacuum distillation, a supercritical gas extraction method, a fractional crystallization (for example, melted liquid crystal precipitation and a crystal filtration). Waxes are used in the present invention.
In addition, oxidation, block copolymerization, or graft modification may be performed after the fractionation. For example, those having an arbitrary molecular weight distribution, such as those obtained by removing low molecular weight components, those obtained by extracting low molecular weight components, and those obtained by further removing low molecular weight components by these methods, can be used.

The wax separated by molecular weight has little influence on triboelectrification and does not adversely affect developability. Therefore, it is particularly preferable in the case of the present invention.

The wax used in the present invention has a melting point of 7
A melt viscosity of 500c at 160 ° C at 0 to 155 ° C
It is preferably P or lower and has a melting point of 75 to 145 ° C.
More preferably, the melt viscosity at 140 ° C. is 1000 cP or less, and the melting point is 80 to 135 ° C.
It is particularly preferable that the melt viscosity at 0 ° C. is 500 cP or less.

As the magnetic powder used in the toner used in the present invention, powders of alloys and compounds containing ferromagnetic elements are preferably used. Examples thereof include alloys and compounds of iron such as magnetite, maghemite, and ferrite, cobalt, nickel, manganese-zinc, and the like, and other ferromagnetic alloys that are conventionally known as magnetic materials.

In addition, S is formed on the surface or inside of the magnetic powder particles.
oxides of metal ions such as i, Al and Mg, hydrous oxides,
A substance containing a compound such as hydroxide can be used.

It is also possible to use a magnetic powder particle on which a coupling agent, a fatty acid compound, an organic compound such as a resin reacts, adsorbs, or adheres.

The shape of the magnetic material is octahedron, hexahedron,
There are spherical, needle-like, and scale-like shapes.

[0159] The BET specific surface area by nitrogen gas adsorption method of magnetic, 1m ² / g~40m ² / g Further, 2
those of m ² / g~30m ² / g are preferred.

The saturation magnetization of the magnetic material is preferably 5 emu / g to 200 emu / g, more preferably 10 emu / g to 150 emu / g in a magnetic field of 10 K oersted.

The residual magnetization of the magnetic material is preferably 1 emu / g to 100 emu / g, more preferably 1 emu / g to 70 emu / g in a magnetic field of 10 K Oersted.

The average particle diameter of the magnetic material is 0.05 to
The thickness is preferably 1.0 μm, more preferably 0.1 to 0.6 μm, further preferably 0.1 to 0.4 μm.

The content of the magnetic powder in the toner is preferably 5 to 200 parts by weight, more preferably 10 to 150 parts by weight, based on 100 parts by weight of the binder resin. If the amount is less than 5 parts by weight, the magnetic force of the toner is small and fogging and scattering are likely to occur. If it exceeds 200 parts by weight, the fixing property tends to be impaired. The physical properties and the amount of the magnetic material used are selected so as to satisfy the magnetic characteristics of the magnetic toner which is a feature of the present invention. Therefore, the choice is important.

The following charge control agents are preferably added in order to give the toner a distribution of the amount of charge, which is a feature of the present invention. It is controlled according to the other constituent materials, the type of compound to be added, and the amount added. You can

(1) The following substances are used to control the toner to be positively charged.

Modified products of nigrosine and fatty acid metal salts; quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate and tetrabutylammonium tetrafluoroborate;
And onium salts such as phosphonium salts which are analogs thereof, and these lake facials, triphenylmethane dyes and these lake facials, (as a laker, phosphotungstic acid, phosphomolybdic acid, phosphotungsten molybdic acid , Anionic acid, lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.) metal salts of higher fatty acids; dibutyltin oxide, dioctyltin oxide, diorganotin oxide such as dicyclohexyltin oxide; dibutyltin borate, dioctyltin borate, cyclohexyl Diorgano tin borates such as tin borate; guanidinin compounds, imidazole compounds. These can be used alone or in combination of two or more. Among these, a triphenylmethane compound and a quaternary ammonium salt whose counter ion is not halogen are preferably used. In addition, the general formula (1)

[0167]

[Outside 5] [R ₁ : H, CH ₃ R ₂ , R ₃ : a substituted or unsubstituted alkyl group (preferably C _{1 to} C ₄ )], a homopolymer of a monomer: styrene described above,
A copolymer with a polymerizable monomer such as acrylic acid ester and methacrylic acid ester can be used as a positive charge control agent. In this case, these charge control agents also function as (all or part of) the binder resin.

Particularly, the compound represented by the following general formula (II) is preferable in the constitution of the present invention.

[0169]

[Outside 6] [Wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ , and R ⁶ are the same or different from each other, a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. Represents a group. R ^{7 ,} R ⁸ and R ⁹ are each the same or different from each other, a hydrogen atom, a halogen atom,
It represents an alkyl group or an alkoxy group. A ^- is an anion such as sulfate ion, nitrate ion, borate ion, phosphate ion, hydroxide ion, organic sulfate ion, organic sulfonate ion, organic phosphate ion, carboxylate ion, organic borate ion, and tetrafluoroborate. Indicates. ] The following substances control the toner to be negatively charged.

Organic metal complexes and chelate compounds are effective, for example, monoazo metal complexes, acetylacetone metal complexes, aromatic hydroxycarboxylic acids, and aromatic dicarboxylic acid metal complexes. Other examples include aromatic hydroxycarboxylic acids, aromatic mono- and polycarboxylic acids and their metal salts, anhydrides, esters, and phenol derivatives such as bisphenol.

Further, an azo metal complex represented by the following general formula (3) is preferable.

[0172]

[Outside 7] [In the formula, M represents a coordination center metal, and Sc, Ti, V, C
Examples thereof include r, Co, Ni, Mn, and Fe. Ar is an aryl group, and examples thereof include a phenyl group and a naphthyl group, which may have a substituent. Examples of the substituent in this case include a nitro group, a halogen group, a carboxyl group, an anilide group, an alkyl group having 1 to 18 carbon atoms, and an alkoxy group. X, X ', Y, Y'are -O-, -CO-,
-NH-, -NR- (R is an alkyl group having 1 to 4 carbon atoms)
Is.

[0173]

[Outside 8] Indicates hydrogen, sodium, potassium, ammonium, aliphatic ammonium or none. In particular, Fe and Cr are preferable as the central metal, halogen, an alkyl group and an anilide group are preferable as the substituent, and hydrogen, ammonium and aliphatic ammonium are preferable as the counter ion.

Alternatively, the basic organic acid metal complex represented by the following general formula (4) also imparts a negative charging property and can be used in the present invention.

[0175]

[Outside 9] [In the formula, M represents a coordination center metal, and Cr, Co, N
Examples thereof include i, Mn, Fe, Zn, Al, Si and B. A is

[0176]

[Outside 10] (May have a substituent such as an alkyl group),

[0177]

[Outside 11] (X represents a hydrogen atom, a halogen atom or a nitro group) and

[0178]

[Outside 12] (R represents a hydrogen atom or a C ₁ -C ₁₈ alkyl or alkenyl group).

[0179]

[Outside 13] Is hydrogen, sodium, potassium, ammonium, aliphatic ammonium or none. Z is -O-
Or

[0180]

[Outside 14] Is. In particular, Fe and Cr are preferable as the central metal, an alkyl group, an aryl group and halogen are preferable as the substituents, and hydrogen, ammonium and aliphatic ammonium are preferable as the counter ion.

As a method of incorporating the charge control agent into the toner, there are a method of adding it inside the toner and a method of adding it externally. The amount of these charge control agents used is determined according to the type of binder resin, the presence or absence of other additives, and the toner manufacturing method including the dispersion method, and is not uniquely limited. It is preferably used in an amount of 0.1 to 10 parts by weight, more preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the binder resin. In addition, when adding externally, resin 1
It is preferably 0.01 to 10 parts by weight with respect to 00 parts by weight, and particularly preferably mechanochemically fixed to the surface of the toner particles.

In the present invention, since the opportunity for imparting triboelectrification is small, the chargeability of the toner itself is important, and the selection and use amount of the charge control agent are important.

In producing the toner according to the present invention, the toner constituent materials as described above are thoroughly mixed by a ball mill or other mixing machine, and then thoroughly kneaded by using a heat kneader such as a heat roll kneader or an extruder. It is preferable to obtain a toner by mechanically pulverizing and classifying the pulverized material after cooling and solidifying the kneaded material. Another method is to obtain a toner by dispersing constituent materials in a solution of a binder resin and then spray-drying; a predetermined material is mixed with a monomer that constitutes the binder resin, and an emulsion suspension is obtained. Then, there is a method for producing a toner by a polymerization method in which the toner is polymerized to obtain a toner. The toner according to the present invention may be a microcapsule toner including a core material and a shell material.

Further, if necessary, desired additives can be sufficiently mixed with a mixer such as a Henschel mixer to obtain the toner according to the present invention.

[0185] Further, the charging property, durability, and
In order to impart cleaning properties and fluidity, it is also preferable to externally mix the following substances.

For example, finely powdered silica such as wet-process silica and dry-process silica, treated silica obtained by subjecting the silica to a surface treatment with a silane coupling agent, a titanium coupling agent, silicon oil, alumina, titania, germanium oxide, Inorganic fine powders such as metal oxides such as zirconium oxide, carbides such as silicon carbide and titanium carbide, and nitrides such as silicon nitride and germanium nitride.

The inorganic fine powder used in the present invention is used in an amount of 0.01 to 8 parts by weight, preferably 0.1 to 4 parts by weight, based on 100 parts by weight of the toner.

Fine powders produced by vapor-phase oxidation of metal halides are preferable, so-called dry methods, and those produced by conventionally known techniques. For example, the thermal decomposition oxidation reaction of silicon tetrachloride gas in oxyhydrogen flame is utilized, and the basic reaction formula is as follows.

SiC1 ₄ + 2H ₂ + O ₂ → SiO ₂ + 4HC1

In this manufacturing process, it is also possible to obtain a fine composite powder of silica and another metal oxide by using another metal halogen compound such as aluminum chloride or titanium chloride together with a silicon halogen compound. Also includes.

On the other hand, as the method of manufacturing by the wet method, various conventionally known methods can be applied. For example, the decomposition of sodium silicate with acid, Na ₂ O.
XSiO ₂ + HC1 + H ₂ O → SiO ₂ · nH ₂ O + N
aC1 Others, ammonia of sodium silicate is decomposed by salts or alkali salts, alkaline earth metal silicate is generated from sodium silicate, and then decomposed with acid to obtain silicic acid, natural silicic acid or silicate There is a method to use.

The weight average diameter thereof is preferably in the range of 0.001 to 2.0 μm on average of the primary particles,
It is particularly preferable to use an inorganic powder having a particle size of 0.002 to 0.2 μm.

Further, it is more preferable to use a treated inorganic fine powder which is subjected to a hydrophobic treatment to the produced inorganic fine powder.
It is particularly preferable that the treated silica fine powder is treated with an inorganic fine powder so that the hydrophobicity measured by a methanol titration test has a value in the range of 30 to 100.

As a method of hydrophobizing, it is imparted by chemically treating with an organic silicon compound which reacts or physically adsorbs with the inorganic fine powder. As a preferred method, inorganic fine powder produced by vapor phase oxidation of a metal halogen compound is treated with an organosilicon compound.

Examples of such organosilicon compounds are hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methotretrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, benzyl. Dimethylchlorosilane, brommethyldimethylchlorosilane, α-chloroethyltrichlorosilane, ρ-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilylmercaptan, trimethylsilylmercaptan, triorganosilylacrylate, vinyldimethylacetoxysilane, dimethylethoxy Silane, dimethyldimethoxysilane, diphenyldiethoxysilane, hexamethyldisiloxane, 1,3-divinyltetramethyl Disiloxane, 1,3-diphenyltetramethyldisiloxane and 2 to 12 per molecule
For example, there is dimethylpolysiloxane having siloxane units and each terminal unit having a hydroxyl group bonded to Si.

Alternatively, untreated silica fine powder treated with a nitrogen-containing silane coupling agent may be used.

Examples of such a treating agent include aminopropyltrimethoxysilane, aminopropyltriethoxysilane, dimethylaminopropyltrimethoxysilane, diethylaminopropyltrimethoxysilane, dipropylaminopropyltrimethoxysilane, dibutylaminopropyltrisilane. Methoxysilane, monobutylaminopropyltrimethoxysilane, dioctylaminopropyltrimethoxysilane, dibutylaminopropyldimethoxysilane, dibutylaminopropylmonomethoxysilane, dimethylaminophenyltriethoxysilane, trimethoxysilyl-γ-propylphenylamine, trimethoxy Silyl-γ-propylbenzinamine, trimethoxysilyl-γ-propylpiperidine, trimethoxysilyl-γ-propylmol Phosphorus, trimethoxysilyl -
γ-propylimidazole and the like.

These treatment agents are used alone or as a mixture of two or more kinds.

The silicone oil is generally represented by the following formula.

[0200]

[Outside 15] [In the formula, R represents an alkyl group (for example, a methyl group), and n
Indicates an integer. ] As a preferred silicone oil,
Viscosity at 25 ° C. is approximately 5 × 10 ^{2 to} 5 × 10 ⁵ c
m ² / s is used, and for example, methyl silicone oil, dimethyl silicone oil, phenyl methyl silicone oil, chlorophenyl methyl silicone oil, alkyl modified silicone oil, fatty acid modified silicone oil, polyoxyalkylene modified silicone oil and the like are preferable.

Further, silicone oil having a nitrogen atom in its side chain may be used. As such silicone oil, silicone oil having at least a partial structure represented by the following formula can be used.

[0202]

[Outside 16] (In the formula, R ₁ represents hydrogen, an alkyl group, an aryl group or an alkoxy group, R ₂ represents an alkylene group or a phenylene group, R ₃ and R ₄ represent hydrogen, an alkyl group or an aryl group, and R ₅ Represents a nitrogen-containing heterocyclic group)
The alkyl group, aryl group, alkylene group and phenylene group may have an organo group having a nitrogen atom, or may have a substituent such as halogen within a range not impairing the charging property.

These silicone oils may be used alone or in combination.
Used in mixtures of more than one species.

It is also preferable to add the following inorganic powder in order to improve the developability and durability. Magnesium, zinc, aluminum, cerium, cobalt, iron, zirconium, chromium, manganese, strontium, tin,
Metal oxides such as antimony; complex metal oxides such as calcium titanate, magnesium titanate, strontium titanate; metal salts such as calcium carbonate, magnesium carbonate, aluminum carbonate; clay minerals such as kaolin;
Phosphoric acid compounds such as apatite; silicon compounds such as silicon carbide and silicon nitride; carbon powders such as carbon black and graphite. Of these, zinc oxide, aluminum oxide, cobalt oxide, manganese dioxide, strontium titanate, magnesium titanate and the like are preferable.

For the same purpose, it is also preferable to add the following organic particles or composite particles. Polyamide resin particles, silicone resin particles, silicone rubber particles, urethane particles,
Resin particles such as melamine-formaldehyde particles and acrylic resin particles; composite particles composed of rubber, wax, fatty acid compound, resin and the like and inorganic particles such as metal, metal oxide, salt and carbon black.

Further, the following lubricant powder can be added. Fluorine resins such as Teflon and polyvinylidene fluoride; Fluorine compounds such as carbon fluoride. Fatty acid metal salts such as zinc stearate; fatty acid derivatives such as fatty acids and fatty acid esters. Included are molybdenum sulfide, amino acids and amino acid derivatives.

In the present invention, the type and molecular weight distribution of the binder resin and the shape and particle size of the magnetic material are used as the toner so that the toner has the charge amount distribution which is the feature of the present invention on the toner carrier. It is achieved by controlling the specific surface area, the type and content of the charge control agent, and the type and addition amount of the external additive. The process conditions can be controlled by the material of the doctor blade and the material and shape of the sleeve surface. Also, by using a toner with a specific weight average diameter,
It is possible to make the charge amount moderate and to facilitate control of the magnetic properties of the toner. As the toner has the magnetic characteristics that characterize the present invention in the developing area, the toner is achieved by the magnetic characteristics and the content of the magnetic substance used in the toner according to the strength of the magnetic pole of the magnetic generation means. It In this way, the toner is electrostatically and magnetically controlled on the toner carrier, which means that the diameter of the latent image carrier and / or the toner carrier is reduced, the curvature is increased, and the developing area is increased. It is very important in cases where is narrow.

When the diameter of the latent image carrier becomes small and the curvature becomes large, the contact charging method is used.
Uniform charging can be performed with a simple structure, and the amount of ozone generated can be suppressed. Furthermore, by using the contact transfer method, transfer can be performed efficiently and ozone generation can be further reduced. Further, by cleaning with a blade, it is possible to efficiently clean a latent image holding member having a large curvature with a simple structure.

By using it together with a toner carrier having a small diameter, the image forming apparatus can be easily downsized with a simple structure and can be easily maintained.

As described above, the toner in the developing portion is electrostatically and magnetically controlled even when the latent image holding member and the toner carrying member have a small diameter and a large curvature, and the developing area is narrowed. Therefore, good development can be performed. Therefore, good development can be performed even in a compact image forming apparatus.

On the other hand, by the material of the surface of the latent image holding member and the magnetic toner as in the present invention, an image forming method excellent in cleaning property and durability and suitable for blade cleaning can be achieved, and further, contact charging and contact transfer can be achieved. In the process of
It is possible to exhibit excellent durability, promote simplification and downsizing of the image forming apparatus, suppress ozone generation, and obtain a more personal image forming apparatus.

The weight average diameter of the toner used in the present invention is
It can be measured by various methods, but in the present invention, it was performed using a multisizer.

That is, Multisizer II (manufactured by Coulter, Inc.) is used as a measuring device, and an interface (manufactured by Nikkaki) and CX-1 for outputting number distribution and volume distribution.
Connect a personal computer (Canon) and use electrolyte of 1% N with special grade or primary grade sodium chloride.
Prepare an aCl aqueous solution. As a measuring method, a surfactant, preferably an alkylbenzene sulfonate, is added as a dispersant in 100 to 150 ml of the electrolytic aqueous solution in an amount of 0.1 to 5 m.
1 and 2 to 20 mg of the measurement sample are further added. The electrolytic solution in which the sample was suspended was subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and when the toner particle size was measured as an aperture by the Multisizer II type, it was measured using a 100 μm aperture. The volume and the number of the toner were measured to calculate the volume distribution and the number distribution. Then, the weight-based weight average diameter obtained from the volume distribution according to the present invention was obtained from the volume distribution.

In the present invention, the magnetic characteristics of the magnetic toner are as follows using VSM P-1-10 (manufactured by Toei Industry Co., Ltd.).
It was determined from the result of measurement with an external magnetic field of 10 K Oersted at room temperature.

The charge amount distribution of the toner or the developer on the developer carrying member is measured, for example, as follows.

As the measuring device, a commercially available Espert analyzer (E.Spart-analyzer (manufactured by Hosokawa Micron Corporation) with a modified sample intake port is used.

A schematic diagram of the sampling device is shown in FIG.

The sampling port 904 of the developer sampling device 903 is opposed to the developing pole position 908 of the grounded developer carrier 902 at a distance of 500 μm. A gold-plated tungsten wire is stretched as a grid 905 at the sampling port 906 as shown in FIG. Further, this grit 905 is connected to the bias 907. The end 901 connects to the sample intake of the E-Spart Analyzer.

Sampling is performed according to the following principle.

By the bias 907, the developer carrier 90
Between 2 and grid 905, 2.8KVpp, 1.8K
A rectangular AC electric field of Hz and a DC electric field of ± 0.3 KV are applied. (If the toner has a positive charging property, -0.3 KV is applied, and if the toner has a negative charging property, +0.3 KV is applied.) Further, the sample intake air of the E-Spart analyzer is sucked at a flow rate of 0.4 l / min.

By the force of this electric field and the force of suction, the developer 906 on the developer carrier 902 flies and is taken in through the sampling port 904, passes through the end portion 901, and passes through E-S.
It is guided to the part analyzer measuring section, and the charge amount distribution of the toner is measured. The applied voltage in the E-Spart analyzer measuring unit is set to 0.1 KV for measurement.

The number of measurement is about 10,000.

The conversion of the Q / M distribution is performed by converting the particle shape into a spherical shape.

[0224]

The present invention will be described below with reference to specific examples, but these examples do not limit the present invention. Parts in the following formulations are parts by weight. First, the magnetic toner used in the present invention will be described. The physical properties of the magnetic toner are shown in Table 1.

[Production Example of Magnetic Toner ] 100 parts by weight of magnetic toner 1 / styrene-butyl acrylate copolymer (Mn 7,200, Mw 213,000, molecular weight 14,000 and molecular weight distribution having peaks at 790,000)・ Magnetic iron oxide 80 parts by weight (remanent magnetization 12.1 emu)
/ G, saturation magnetization 81.2 emu / g specific surface area 8.2
m ² / g, average particle size 0.18 μm) 4 parts by weight of low molecular weight polyethylene (melting point 120 ° C.,
Melt viscosity 95 cP / 140 ° C) 2 parts by weight of triphenylmethane compound

[0226]

[Outside 17]

After the above materials were premixed, they were melt-kneaded by a twin-screw kneading extruder set at 130 ° C.
The kneaded product was cooled, coarsely pulverized, finely pulverized by a pulverizer using a jet stream, and further classified by an air classifier to obtain classified powder (magnetic toner). Classified product (magnetic toner)
A magnetic toner 1 was prepared by adding 0.6 part by weight of amino-modified silicone oil-treated dry silica fine powder to 100 parts by weight.
And

Magnetic toner 2 -Styrene-butyl acrylate copolymer 100 parts by weight (Mn 6,300, Mw 242,000, molecular weight 12,100 and molecular weight distribution having a peak at 727,000) -Magnetic iron oxide 100 Parts by weight (remanent magnetization 4.7 emu
/ G, saturation magnetization 84.0 emu / g specific surface area 6.
9 m ² / g, average particle diameter 0.16 μm) Hydrocarbon wax 4 parts by weight (melting point 115 ° C., melt viscosity 15 cP / 140 ° C.) 1 part by weight triphenylmethane compound (used in magnetic toner 1)

A classified product (magnetic toner) was obtained in the same manner as the magnetic toner 1 using the above materials, and 0.9 part by weight of dry silica treated with aminosilane coupling agent was added to 100 parts by weight of the classified product (magnetic toner). Magnetic toner 2 was obtained by externally adding 0.2 part by weight of polyvinylidene fluoride powder.

Magnetic toner 3 Styrene-butyl acrylate-monobutyl maleate copolymer 100 parts by weight (Mn 4,200, Mw)
353,000, molecular weight 10,100 and 1,05
It has a molecular weight distribution with a peak at 20,000) -Magnetic iron oxide 80 parts by weight (remanent magnetization 10,2 emu)
/ G, saturation magnetization 81,1 emu / g specific surface area 22.
3 m ² / g, average particle diameter 0.24 μm) 4 parts by weight of low molecular weight polypropylene (melting point 143
° C, melt viscosity 251 cP / 160 ° C) ・ Monoazo iron complex 1 part by weight

[0231]

[Outside 18]

A classified product (magnetic toner) is obtained in the same manner as the magnetic toner 1 using the above materials, and 0.8 part by weight of silicone oil-treated dry silica is externally added to 100 parts by weight of the classified product (magnetic toner). The magnetic toner 3 is obtained.

Magnetic toner 4 / polyester resin 100 parts by weight (Mn 5,00
0, Mw 50,000, acid value 11.0, bisphenol A (EO, PO adduct), terephthalic acid, n-dodecenylsuccinic acid, trimellitic acid in a molar ratio of 52:23:
20: 5) ・ Magnetic iron oxide 100 parts by weight (residual magnetization 10.2 em
u / g, saturation magnetization 86.1 emu / g, specific surface area 7.
1 m ² / g, average particle diameter 0.21 μm) Hydrocarbon wax 4 parts by weight (melting point 108 ° C., melt viscosity 11 cP / 140 ° C.) ・ Monoazo iron complex 1 part by weight

[0234]

[Outside 19]

A classified product (magnetic toner) was obtained in the same manner as the magnetic toner 1 using the above materials, and 1.0 part by weight of silicone oil-treated wet silica fine powder was added to 100 parts by weight of the classified product (magnetic toner). Magnetic toner 4 was obtained by externally adding 1.0 part by weight of cerium oxide fine powder.

Magnetic toner 5 -Styrene-2-ethylhexyl acrylate-divinimebenzene copolymer 70 parts by weight (Mn 15,000)
0, Mw 430,000) -Styrene-butadiene copolymer 30 parts by weight (Mn
24,000, Mw 210,000) 70 parts by weight of magnetic iron oxide (remanent magnetization 12.1 emu)
/ G, saturation magnetization 83.7 emu / g specific surface area 8.3
m ² / g, average particle diameter 0.21 μm) 4 parts by weight of low molecular weight polyethylene (melting point 126 ° C.,
Melt viscosity 255 cP / 140 ° C) ・ Nigrosine 2 parts by weight

A classified product (magnetic toner) was obtained in the same manner as the magnetic toner 1 using the above materials, and 0.6 part by weight of amino-modified silicone oil treated wet silica fine powder was added to 100 parts by weight of the classified product (magnetic toner). Parts and 1.0 part by weight of strontium titanate fine powder were externally added to obtain a magnetic toner 5.

Magnetic toner 6 Styrene-butyl methacrylate-monobutyl maleate-divinylbenzene copolymer 60 parts by weight (Mn
12,000, Mw 910,000, gel component 28
Wt%)-Polyester resin 40 parts by weight (used in magnetic toner 4) -Magnetic iron oxide 80 parts by weight (residual magnetization 17.6 emu)
/ G, saturation magnetization 86.4 emu / g, specific surface area 7.6
m ² / g, average particle diameter 0.23 μm) 4 parts by weight of low molecular weight polyethylene (melting point 117 ° C.,
Melt viscosity 15 cP / 140 ° C.) 2 parts by weight of 3,5-di-t-butylsalicylic acid chromium complex

A classified product (magnetic toner) is obtained in the same manner as the magnetic toner 1 using the above materials, and 100 parts by weight of the classified product (magnetic toner) is treated with a silicone oil and a silane coupling agent. Magnetic toner 6 was obtained by externally adding 6 parts by weight and 0.2 parts by weight of polymethylmethacrylate resin particles.

Magnetic toner 7 Styrene-butyl acrylate-divinylbenzene copolymer 100 parts by weight (Mn 15,000, Mw 4
30,000) -Magnetic iron oxide 80 parts by weight (remanent magnetization 11.4 emu
/ G, saturation magnetization 82.6 emu / g specific surface area 7.9
m ² / g, average particle size 0.20 μm) 4 parts by weight of low molecular weight polyethylene (melting point 126 ° C.,
Melt viscosity 255 cP / 140 ° C) 2 parts by weight of organic quaternary ammonium salt

[0241]

[Outside 20]

A classified product (magnetic toner) was obtained in the same manner as the magnetic toner 1 using the above materials, and 0.6 part by weight of fine silica powder treated with aminosilane coupling agent was added to 100 parts by weight of the classified product (magnetic toner). A part was externally added to obtain a magnetic toner 7.

Magnetic toner 8 Styrene-butyl acrylate-monobutyl maleate-divinylbenzene copolymer 100 parts by weight (Mn
8,000, Mw 43,000, gel component 40Wt
%)-Magnetic iron oxide 80 parts by weight (remanent magnetization 10,0 emu)
/ G, saturation magnetization 83.1 emu / g specific surface area 6.2
m ² / g, average particle size 0.28 μm) 4 parts by weight of low molecular weight polypropylene (melting point 100
℃, melt viscosity 71 cP / 160 ℃) ・ Monoazochrome complex 1 part by weight

[0244]

[Outside 21]

Using the above materials, a classified product (magnetic toner) was obtained in the same manner as the magnetic toner 1, and 0.6 part by weight of silicone oil-treated dry silica fine powder was added to 100 parts by weight of the classified product (magnetic toner). Magnetic toner 8 was added externally.

Magnetic toner 9 (comparative example) 100 parts by weight of styrene-butyl acrylate-divinylbenzene copolymer (Mn 4,200, Mw 5)
8,000) -Magnetic iron oxide 80 parts by weight (remanent magnetization 12.2 emu)
/ G, saturation magnetization 78.9 emu / g specific surface area 6.5
m ² / g, average particle diameter 0.24 μm) 4 parts by weight of low molecular weight polypropylene (melting point 126
° C, melt viscosity 255 cP / 140 ° C) ・ Organic quaternary ammonium chloride 1 part by weight

[0247]

[Outside 22]

A classified product (magnetic toner) was obtained in the same manner as the magnetic toner 1 using the above materials, and 0.6 part by weight of a dry silica fine powder treated with a silane coupling agent was added to 100 parts by weight of the classified product (magnetic toner). A part was externally added to obtain a magnetic toner 9.

Magnetic toner 10 (comparative example) 100 parts by weight of styrene-butyl acrylate-divinylbenzene copolymer (Mn 5,900, Mw 8)
4,000) -Magnetic iron oxide 60 parts by weight (residual magnetization 3.6 emu /
g, saturation magnetization 78.5 emu / g specific surface area 7.5
m ² / g, average particle diameter 0.19 μm) 4 parts by weight of low molecular weight polypropylene (melting point 143
° C, melt viscosity 251 cP / 160 ° C) ・ 3-5-di-t-butylsalicylic acid zinc salt 1 part by weight

A classified product (magnetic toner) was obtained in the same manner as the magnetic toner 1 using the above materials, and 0.6 part by weight of silane coupling-treated dry silica fine powder was added to 100 parts by weight of the classified product (magnetic toner). Was externally added to form a magnetic toner 10.

Magnetic Toner 11 (Comparative Example) A magnetic toner for Canon FC-1 was used as magnetic toner 11.

[0252]

[Table 1]

Device Example 1 As a toner carrier, a 4-pole magnet having a developing pole magnetic flux density of 700 G is provided in an aluminum cylindrical sleeve whose surface having an outer diameter of 12 mm is roughened by blasting with Alundum ^# 400. Use the built-in one.

As the toner regulating member, a stainless steel plate having silicone rubber bonded to the surface thereof was used, and the side of the silicone rubber was brought into contact with the toner carrier as shown in FIG. 3 to regulate the toner layer. At this time, the contact pressure on the toner carrier was 20 g / cm.

As the electrostatic latent image carrier (photosensitive drum),
An aluminum cylinder having an outer diameter of 24 mm was used as a substrate, and a 5% methanol solution of alkoxymethylated nylon was applied to the substrate by a dipping method to form an undercoat layer (intermediate layer) having a film thickness of 1 μm.

Next, 10 parts by weight of the pigment of the following structural formula (5) (parts by weight, the same applies hereinafter) and polyvinyl butyral were used.

[0257]

[Outside 23] 8 parts and 50 parts of cyclohexanone were mixed and dispersed in a sand mill device containing 100 parts of glass beads having a diameter of 1 mm for 20 hours. Methyl ethyl ketone 70-12
0 (appropriate) part is added and coated on the undercoat layer, dried at 100 ° C. for 5 minutes to form a 0.2 μm charge generation layer (CGL)
Was formed.

Next, 10 parts of a styryl compound represented by the following structural formula (6) was formed on the charge generation layer.

[0259]

[Outside 24] 10 parts of bisphenol Z-type polycarbonate was dissolved in 65 parts of monochlorobenzene. This solution was applied onto a substrate by a dipping method and dried by hot air at 120 ° C. for 60 minutes to form a 20 μm thick charge transfer layer.

It was set so that the closest distance between the surface of the toner carrying member and the surface of the electrostatic latent image carrying member was 300 μm. At this time, the developing pole was set so as to be on the line connecting the closest portion and the center of the magnet.

A roller charger was used as the primary charger. The outer diameter of the charging roller is 15 mm, and the conductive rubber is formed of an ethylene-propylene-diene terpolymer (EPDM) in which conductive carbon is dispersed,
The one whose surface was coated with a nylon resin was used.

The hardness of the charging roller was 30 °.

This charging roller is used as an electrostatic latent image bearing member.
The contact was made at g / cm.

At this time, the charging roller was set to rotate following the electrostatic latent image carrier.

A transfer roller device was used as the transfer charger. The outer diameter of the transfer roller is 12 mm, and EPDM in which conductive carbon is dispersed as a conductive elastic layer
Made of rubber.

The rubber hardness of the transfer roller was 60 °.

This transfer roller was brought into contact with the electrostatic latent image carrier at a contact pressure of 45 g / cm. The transfer roller was installed so that the electrostatic latent image carrier was rotated at a constant speed.

A blade cleaning device was used as the cleaning device for removing the toner remaining on the electrostatic latent image carrier in the transfer step, and a urethane rubber blade was used as the cleaning blade. The cleaning blade was brought into contact with the electrostatic latent image carrier at the edge thereof in the direction opposite to the traveling direction at a linear pressure of 40 g / cm.

The image forming apparatus having such a structure is rotated at a linear velocity of the electrostatic latent image carrier of 100 m / sec and a linear velocity of the toner carrier of 150 mm / sec, and the primary charger is -630.
A DC voltage of V was applied and a potential of -600 V was applied on the electrostatic latent image carrier. Exposure was performed there and an electrostatic latent image was formed.

The toner carrier has an alternating electric field of Vpp of 1200 V, Vf of 1800 Hz, and V of -200.
A DC electric field of V was applied and the electrostatic latent image was developed using magnetic toner.

This toner image was transferred to a transfer charging device by applying a DC voltage of -2 KV and passing a current of -1.5 μA to transfer it onto a transfer material, which was heated and fixed by a heating roller fixing device to form a final image. did. The transfer device toner remaining on the electrostatic latent image was removed by a blade cleaner.

Device Example 2 A toner carrier having a coating layer in which carbon black and graphite are dispersed in a ratio of 1: 9 in 10 parts by weight of a phenol resin on the surface of an aluminum cylindrical sleeve having an outer diameter of 12 mm. Using. As the magnet in the toner carrier, the same magnet as in the apparatus example 1 was used.

A urethane blade is used as the toner regulating member, and a contact pressure of 30 g / c is applied to the toner carrier as shown in FIG.
The toner layer was regulated by bringing them into contact with each other at m.

As the electrostatic latent image carrier, one manufactured in the same manner as in the apparatus 1 was used except that the charge generation layer was formed as follows. 4 parts of oxytitanium phthalocyanine and 2 parts of polyvinyl butyral resin were added to cyclohexanone 1
It was added to 00 parts and dispersed for 1 hour with a sand mill using 1 mmφ glass beads, and 100 parts of methyl ethyl ketone was added to dilute it, and this was coated on the undercoat layer and dried at 80 ° C. for 10 minutes. As a result, a charge generation layer having a film thickness of 0.15 μm was formed.

It was set so that the closest distance between the surface of the toner carrier and the surface of the electrostatic latent image carrier was 300 μm. At this time, the developing pole was set so as to be on the line connecting the closest point to the center of the magnet. As the primary charging device, the transfer charging device, and the cleaning device, the same devices as in the device example 1 were used.

The image forming apparatus having such a structure is rotated at a linear velocity of the electrostatic latent image carrier of 50 mm / sec and a linear velocity of the toner carrier of 75 mm / sec, and the primary charger is -620 V.
Was applied, and a potential of -600 V was applied on the electrostatic latent image carrier. There, it was exposed to laser light to form an electrostatic latent image.

On the toner carrier, an alternating electric field having Vpp of 1200 V and Vf of 1800 Hz and V of -5.
An electrostatic latent image was developed using magnetic toner by superimposing a DC electric field of 00V.

This toner image is transferred to the transfer charger by + 2000V.
Was applied to the transfer material to transfer it to a transfer material, and the transfer material was heated and fixed by a fixing device to obtain a final image. The transfer device toner remaining on the electrostatic latent image was removed by a blade cleaner.

Device Example 3 Device 3 was assembled in the same manner as in Device Example 1 except that a two-pole magnet having a developing pole magnetic flux density of 750 G was used as the magnetic generation stage in the developing device of Device Example 1.

Apparatus Example 4 An apparatus 4 was assembled in the same manner as in the apparatus example 1 except that the developing device of the apparatus example 1 uses a magnetic blade as the toner regulating member so that the gap between the toner carrying member and the toner carrying member is 250 μm. Shown in).

Apparatus Example 5 A commercially available electrophotographic copying machine FC-2 (manufactured by Canon Inc .: corona charging, corona transfer method) is used, and the developing device configuration is apparatus example 1.
FC-2 was used as it was, and apparatus 5 was used, except that an apparatus unit (cartridge) modified so as to be the same as the above was used.

Device Example 6 Device 6 was assembled in the same manner as in Device Example 2 except that the latent image carrier of Device Example 2 was a photosensitive drum described below.

Bisphenol Z type polycarbonate 10
Parts, 20 parts of polytetrafluoroethylene and 3 parts of a fluorine-based graft polymer were dissolved in 50 parts of cyclohexanone and 20 parts of tetrahydrofuran, and dispersed for 20 hours in a sand mill using 1 mmφ glass beads.

A protective layer solution was prepared by mixing 90 parts of the obtained dispersion with 20 parts of the above polycarbonate and 40 parts of a resin solution prepared by dissolving 40 parts of cyclohexanone and 20 parts of tetrahydrofuran.

This protective layer solution was applied onto the charge transport layer of the electrostatic latent image bearing member of Apparatus Example 2 and dried in hot air at 100 ° C. for 30 minutes to form a protective layer having a thickness of 3 μm.

Example 1 150 g of the magnetic toner 1 was put in the apparatus 1 and an image forming test was conducted. The coating amount of the magnetic toner on the toner carrier (developing sleeve) was 0.80 mg / cm ² . When the charge amount distribution on the toner carrier was measured by the method described above, the peak in the number distribution of the charge amount per unit weight was +4.5 μC / g, and the ratio of the negatively charged component was , 2.1% by number. Figure 1 shows the number distribution chart
2 shows. When the image forming test was repeated 3000 times, images with high image density and uniform density were continuously obtained until the end without fog. Furthermore, uneven pitch due to gears and sleeves was not noticeable. In addition, there was no occurrence of filming, fusion, and cleaning failure. The evaluation results are shown in Table 3. At this time, the amount of waste toner in the cleaner was small and the amount of toner consumed in the developing device was small. Therefore, it was found that the cleaner capacity and the developing hopper capacity can be reduced, or a large number of toner images can be obtained with the same capacity. The toner utilization ratio, which is the ratio of the toner transferred on the image to the consumed toner, was 89%, which was good.

Examples 2 to 12 An image forming test was conducted in the same manner as in Example 1 using the combinations of toner and apparatus shown in Table 2, and the results are shown in Table 3. The state of the toner on the toner carrier, the developability (image density, fog, density uniformity) durability (filming, fusing, cleaning failure), utilization rate and the like.

Comparative Example 1 An image forming test was conducted using the combination of toner and apparatus shown in Table 2 and the results are shown in Table 3. The state of the toner on the toner carrier, the developability (image density, fog, density uniformity) durability (filming, fusing, cleaning failure), utilization rate and the like. The image density was low, and uneven density was observed in the solid image, and uneven pitch was noticeable.

Comparative Example 2 An image forming test was conducted using the combination of toner and device shown in Table 2 and the results are shown in Table 3. The state of the toner on the toner carrier, the developability (image density, fog, density uniformity) durability (filming, fusing, cleaning failure), utilization rate and the like. The fogging was bad, the fogging on the uneven pitch was particularly noticeable, and the utilization rate was also poor.

Comparative Example 3 Commercially available magnetic toner for FC-1 (weight average diameter: 12.1 μm)
m, remanent magnetization 3.98 emu / g), Example 1
An image forming test similar to the above was performed. The results are shown in Table 3. In this test, the image density was low, especially at the initial stage and after rest, and fogging was likely to occur during durability.

[0291]

[Table 2]

[0292]

[Table 3]

[0293]

According to the present invention, it is possible to obtain an image having excellent developability on a latent image carrier having a small diameter and a toner carrier, having no fog, and having no unevenness in image density. Further, the image forming apparatus can be made compact while maintaining high image quality. Further, by using the contact charging means, the blade cleaning, etc., the image forming apparatus can be simpler, easier to maintain, and more personal.

[Brief description of drawings]

FIG. 1 is a schematic view showing an image forming apparatus and a developing process for carrying out an image forming method of the present invention.

FIG. 2 is a diagram showing a schematic view of a developing device using an elastic blade for carrying out the image forming method of the present invention.

FIG. 3 is a diagram showing a schematic view of a developing device using an elastic blade for carrying out the image forming method of the present invention.

FIG. 4 is a diagram showing a schematic view of a developing device using an elastic blade for carrying out the image forming method of the present invention.

FIG. 5 is a schematic view of a developing device using an elastic blade for carrying out the image forming method of the present invention.

FIG. 6 is a diagram showing a schematic view for explaining an image forming method of the present invention.

FIG. 7 is a diagram showing a schematic diagram for explaining a transfer step.

FIG. 8 is a diagram showing a schematic diagram for explaining a transfer step.

FIG. 9 is a schematic view of a sampling device of a charge amount distribution measuring device for measuring the charge amount distribution of toner.

10 is an enlarged view of a sampling port in the sampling device shown in FIG.

FIG. 11 is a diagram showing a schematic view of an image forming apparatus using a magnetic blade for carrying out the image forming method of the present invention.

FIG. 12 is a diagram showing the distribution of the charge amount of magnetic toner in Example 1.

FIG. 13 is a diagram showing a schematic view of a specific example of the apparatus unit of the present invention.

FIG. 14 is a schematic view showing a specific example of an image forming apparatus equipped with the apparatus unit of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Latent image holder (photosensitive drum) 2 Developing device 21 Hopper 22 Toner carrier (developing sleeve) 23 Magnetic generation means 24 Doctor blade 27 Stirring member A Development area a Gap between drum and sleeve T Toner T1 Toner thin layer T2 Toner image So, S ₁ bias applying means 201, 301, 401, 501 latent image carrier 202, 302, 402, 502 toner carrier 203, 303, 403, 503 doctor blade 601 latent image carrier 601a photoconductive layer 601b conductive base layer 602 charging roller 602a conductive elastic layer 602b core metal 603 charging bias power supply 604 image exposure 605 developing device 606 transfer roller 606a conductive elastic layer 606b core metal 607 transfer bias power supply 608 transfer material 609 cleaning device 810 conductive roller 901 Sample introduction port to analyzer 902 Development sleeve 903 Developer (toner) sampling device 904 Sampling port 905 Grid 906 Developer (toner) 907 Bias 101 Latent image carrier 102 Toner carrier 103 Magnetic doctor blade

Claims (13)

[Claims] 1. A toner image holding member for holding an electrostatic charge image, and a toner holding member carrying magnetic toner on its surface and having a magnetism generating means inside are arranged with a certain gap in a developing unit, In the image forming method, a magnetic toner layer is formed on a carrier and conveyed to a developing unit, and an electrostatic charge image is developed with a magnetic toner while applying a bias between the toner carrier and the latent image carrier. The diameter of the carrier is 7 to 15 mm, and the magnetic flux density on the toner carrier in the developing section is 4
00G or more and the residual magnetization of the magnetic toner is 1.5 to
10 emu / g, and in the number distribution of the charge amount of the magnetic toner per unit weight of the magnetic toner on the toner carrier, the position of the maximum peak is 2 to 30 μc / g (absolute value), 40% by number or more of components having the same polarity and a larger charge amount (absolute value) than the charge amount,
The component having a charge amount (absolute value) from the maximum peak charge amount (absolute value) to the same polarity as the maximum charge amount up to 10 μc / g is 30 number% or more, and the charge amount is 4 or more.
An image forming method comprising developing an electrostatic charge image with a magnetic toner satisfying a condition that a component of 0 μc / g or more (absolute value) is 10 number% or less. 2. The image forming method according to claim 1, further comprising a step of cleaning the magnetic toner remaining on the surface of the latent image carrier with a blade. 3. The image forming method according to claim 1, further comprising a step of charging the latent image holding member by a contact charging unit that contacts the surface of the latent image holding member. 4. The image forming method according to claim 1, further comprising the step of electrostatically transferring the toner image formed on the surface of the latent image holding member while pressing the transfer material with a transfer member to which a voltage is applied. Method. 5. A toner image holding member for holding an electrostatic charge image and a toner holding member carrying a magnetic toner on the surface thereof and having a magnetism generating means inside thereof are arranged in the developing section with a certain gap provided therebetween. In the image forming method, a magnetic toner layer is formed on a carrier and conveyed to a developing unit, and an electrostatic charge image is developed with magnetic toner while applying a bias between the toner carrier and the latent image carrier. The diameter of the image carrier is 14 to 29 mm, and the residual magnetization of the magnetic toner is 1.5 to 10 emu /
In the number distribution of the charge amount of the magnetic toner per unit weight of the magnetic toner on the toner carrier, the maximum peak position is 2 to 30 μc / g (absolute value), and the maximum peak charge amount is 40% by number or more of components having the same polarity and a larger charge amount (absolute value) than the maximum peak charge amount (absolute value) to a maximum charge amount of 10 μc / g with the same polarity (absolute value). The electrostatic charge image is developed with a magnetic toner satisfying the conditions that the component having an absolute value is 30 number% or more and the component having a charge amount of 40 μc / g or more (absolute value) is 10 number% or less. And an image forming method. 6. The image forming method according to claim 5, further comprising a step of cleaning the magnetic toner remaining on the surface of the latent image carrier with a blade. 7. The image forming method according to claim 5, further comprising a step of charging the latent image holding member by a contact charging unit that is in contact with the surface of the latent image holding member. 8. The image formation according to claim 5, 6 or 7, further comprising the step of electrostatically transferring the toner image formed on the surface of the latent image holding member while pressing the transfer material with a transfer member to which a voltage is applied. Method. 9. A toner image holding member for holding an electrostatic charge image and a toner holding member for carrying a magnetic toner on the surface thereof and having a magnetism generating means inside thereof are arranged in the developing section with a constant gap provided therebetween. In the image forming method, a magnetic toner layer is formed on a carrier and conveyed to a developing unit, and an electrostatic charge image is developed with a magnetic toner while applying a bias between the toner carrier and the latent image carrier. The diameter of the carrier is 7 to 15 mm, and the magnetic flux density on the toner carrier in the developing section is 4
00G or more, and the diameter of the latent image carrier is 14 to 29 m
m, and the residual magnetization of the magnetic toner is 1.5 to 10 em.
u / g, in the number distribution of the charge amount of the magnetic toner per unit weight of the magnetic toner on the toner carrier,
The position of the maximum peak is at 2 to 30 μc / g (absolute value), there are 40 number% or more of components having the same polarity and larger charge amount (absolute value) than the charge amount of the maximum peak, and the charge amount of the maximum peak ( 30% by number or more of components having a larger charge amount (absolute value) with the same polarity from the absolute value) to the maximum peak charge amount of 10 μc / g and a charge amount of 40 μc / g.
An image forming method comprising developing an electrostatic charge image with a magnetic toner satisfying a condition that a component of g or more (absolute value) is 10 number% or less. 10. The method according to claim 9, further comprising the step of cleaning the magnetic toner remaining on the surface of the latent image carrier with a blade.
The image forming method described in 1 .. 11. The image forming method according to claim 9, further comprising the step of charging the latent image holding member by a contact charging unit that contacts the surface of the latent image holding member. 12. The image formation according to claim 9, 10 or 11, further comprising the step of electrostatically transferring the toner image formed on the surface of the latent image holding member while pressing the transfer material with a transfer member to which a voltage is applied. Method. 13. A latent image carrier for holding an electrostatic charge image and a developing device for developing the electrostatic charge image, the developing device including a toner container for containing a magnetic toner.
A toner carrier having magnetic generation means inside for carrying and carrying the magnetic toner in the toner container from the toner container to the developing area facing the latent image carrier, and a magnetic material carried and carried by the toner carrier. And a layer thickness regulating member for regulating the toner to a predetermined thickness to form a magnetic toner layer on the developer carrying member, the diameter of the toner carrying member is 7 to 15 mm, and The magnetic flux density on the toner holder is 40
0G or more, and the diameter of the latent image carrier is 14 to 29 mm
And the residual magnetization of the magnetic toner is 1.5 to 10 emu.
/ G, in the number distribution of the charge amount of the magnetic toner per unit weight of the magnetic toner on the toner carrier, the position of the maximum peak is 2 to 30 μc / g (absolute value),
There are 40% or more of components having the same polarity and larger charge amount (absolute value) than the maximum peak charge amount, and 10 μc / g with the same polarity as the maximum peak charge amount (absolute value) to the maximum peak charge amount. Toner having a triboelectrification characteristic satisfying the condition that the component having a large charge amount (absolute value) is 30 number% or more and the component having a charge amount of 40 μc / g or more (absolute value) is 10 number% or less. Is held in the toner container, the developing device has a terminal for applying a bias to the toner carrier, is integrally supported with the electrostatic image carrier to form a unit, and is detachably attached to the main body of the device. A unit of equipment, characterized in that it forms a single unit of.