JP2003084481A - Toner and elecvtrophotographic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide toners which can prevent drop-out and splashing during transfer in a transfer process of a tandem system of a short distance from a first primary transfer position to a second primary transfer position and a high speed, can prevent filming of a photoreceptor and a transfer medium even in long-term use under high humidity and can prevent an offset characteristic while maintaining high OHP translucency in spite of not coating with oil. SOLUTION: The toners which contain particles of a grain size 2×10<-6> to 5×10<-6> m at 5 to 50 number% and are added with a fixing assistant containing wax of 5 to 40% in the compressibility calculated from a static bulk density and dynamic bulk density, <=25 in iodine value and 30 to 300 in saponification value at 1 to 12 pts.wt. per 100 pts.wt. binder resin of 1 to 70 mgKOH/g in acid value are used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to toner used in color copying machines, color printers and color facsimiles.

[0002]

2. Description of the Related Art In recent years, electrophotographic apparatuses have been shifting from office use to personal use, and there is a demand for a technology that realizes downsizing, high speed operation, high image quality, and maintenance-free operation. Therefore, a cleaner process that does not clean the residual toner after transfer and a tandem color process that enables high-speed output of color images are required along with conditions such as good maintainability and low ozone exhaust.

In a color printer, an image bearing member (hereinafter referred to as "photosensitive member") is charged by corona discharge by a charging charger, and then a latent image of each color is applied to the photosensitive member as an optical signal to form an electrostatic latent image. , The first color, for example, yellow toner is developed to visualize the latent image. After that, the transfer material charged with the opposite polarity to the charging of the yellow toner is brought into contact with the photoconductor,
The yellow toner image formed on the photoconductor is transferred. The photoconductor is destaticized after cleaning the toner remaining at the time of transfer, and finishes development and transfer of the first color toner.
After that, the same operation as that for the yellow toner is repeated for the toners such as magenta and cyan, and the color toner images are superimposed on the transfer material to form a color image. Then, these superposed toner images are transferred to a transfer paper charged with a polarity opposite to that of the toner, and then fixed and copying is completed.

In this color image forming method, toner images of respective colors are sequentially formed on a single photoconductor, and a transfer material wound around a transfer drum is rotated to repeatedly face the photoconductor, and sequentially formed there. A transfer drum method in which toner images of respective colors are transferred in an overlapping manner, and a plurality of image forming units are arranged side by side, and the toner images of respective colors are sequentially passed through a transfer material conveyed by a belt through the respective image forming units. A continuous superposition method of transferring and superimposing color images is common.

As well known, the toner for electrostatic charge development used in the electrophotographic method is generally a resin component which is a binder resin, a coloring component comprising a pigment or a dye and a plasticizer,
It is composed of a charge control agent and, if necessary, an additive component such as a release agent. As the resin component, a natural or synthetic resin may be used alone or may be mixed at an appropriate time.

Then, the above additives are premixed in an appropriate ratio, heated and kneaded by heat melting, finely pulverized by an airflow type collision plate system, and finely powdered to complete a toner base.
Thereafter, an external additive such as hydrophobic silica is externally added to the toner base to complete the toner. In one-component development,
Although it is composed only of toner, a two-component developer can be obtained by mixing the toner and a carrier composed of magnetic particles.

As a releasing agent added for the purpose of improving the fixing property of the toner, Japanese Patent Laid-Open No. 2-266372 discloses a free fatty acid type carnauba wax and / or a montan ester wax and an acid value of 10-30. Use of rice wax, and in JP-A-9-281748, a vinyl-based copolymer polymerized in the presence of a natural gas-based Fischer-Tropsch wax in JP-A-9-281748, in JP-A-10-327196, The polyhydric alcohol component and a dicarboxylic acid and a polyvalent carboxylic acid compound having a valence of 3 or more are polycondensed, and the average dispersed particle diameter of the release agent is 0.1 to 3 μm
m, the particle size of the external additive is 4 to 200 nm, and 1 to 5 parts by weight is added. Japanese Unexamined Patent Publication (Kokai) No. 5-333584 discloses that the fixing property is improved by a constitution containing a fluorine-modified polyolefin resin such as polypropylene modified with an organic fluorine compound such as perfluorooctyl methacrylate. . Japanese Patent Laid-Open No. 5-18
In Japanese Patent No. 8632, the content of the non-offset property at the time of fixing is improved by blending a low molecular weight polyolefin containing fluorine and a melt mixture of low molecular weight olefin and polytetrafluoroethylene with a softening point of 80 to 140 ° C. The contents are disclosed, and the contents effective in improving the fixing property are described.

Further, in Japanese Patent Laid-Open No. 59-148067, an unsaturated ethylene polymer having a low molecular weight and a high molecular weight portion in a resin and having a low molecular weight peak value and Mw / Mn is used to soften the resin. A toner containing a point-specified polyolefin is disclosed. As a result, it is said that the fixability and the offset resistance are secured. In addition, JP-A-5
Japanese Patent Publication No. 6-158340 discloses a toner containing a resin composed of a specific low molecular weight polymer component and a high molecular weight polymer component as a main component. The purpose is to secure the fixability by the low molecular weight component and the offset resistance by the high molecular weight component. Further, in JP-A-58-223155, it is 10
Disclosed is a toner having a maximum value in a molecular weight range of 100,000 to 100,000 and 200,000 to 1,000,000 and containing a resin composed of an unsaturated ethylene polymer having Mw / Mn of 10 to 40 and a polyolefin having a specific softening point. Has been done. The low molecular weight component is used to secure the fixing property, and the high molecular weight component and polyolefin are used to secure the offset resistance.

Further, JP-A-63-56659 and JP-A-2000-98661 disclose a toner relating to a polyester resin, which discloses that a good fixing property can be obtained.

Further, as a charge control agent for imparting chargeability to the toner, Japanese Patent Laid-Open Nos. 2-221967 and 7-
No. 84409, JP-A-5-72812, and JP-A-5-165257 disclose toners using a metal salt of a benzylic acid derivative. In addition, JP-A-53-1
No. 27726, JP-A-55-42752, JP-A-7-2171097 and the like disclose toners using a metal salt of a salicylic acid derivative.

[0011]

In the fixing process, in the color image, it is necessary to melt and mix the color toners to enhance the translucency. When toner melting failure occurs, light scattering occurs on the surface or inside the toner image, impairing the original color tone of the toner dye, and at the overlapping portion, light does not enter the lower layer, resulting in poor color reproducibility. Therefore, it is a necessary condition that the toner has a perfect melting property and has a light-transmitting property that does not disturb the color tone. In particular, the need for greater light transmission on OHP paper is increasing due to the increasing number of color presentation opportunities.

However, in the resin constitution having the melting property of sharp melt due to the expression of the light transmission property, the offset resistance is lowered and an offset occurs by adhering to the surface of the fixing roller, so that a large amount of oil or the like must be applied to the fixing roller. This complicates handling and device configuration. Therefore, an oilless color fixing structure that does not require oil is required.

Further, when a silicone-based material or a fluorine-based material having a strong charging property is used for the fixing roller and the belt, an undisturbed toner image is apt to electrostatically repel an unfixed toner image before entering the fixing portion, which causes image disturbance. . On the contrary, the toner may fly to the fixing roller before entering the fixing nip portion to cause a halftone offset. In particular, the influence of the charging property is likely to occur in the configuration where the release oil is not applied. Further, in a toner to which a release agent is added for the purpose of improving the offset property, the fixing roller is likely to be scratched due to the poor dispersion of the internal additive, which causes a vertical streak in the image.

Further, for the purpose of flexibility, downsizing of the apparatus, and shortening of warm-up, a belt fixing system in which a medium heating section and a toner melting and fixing section are separated is being used.
Therefore, the diameter of the fixing roller can be reduced to reduce the size of the apparatus. Further, since the curvature of the paper discharge portion becomes large, the paper is less likely to be wound around the belt. The low heat capacity of the belt reduces warm-up. However, when the toner has a certain amount of high molecular weight component added to prevent high-temperature offset and has a certain elastic element, the paper on which the pattern of thin vertical lines is drawn is separated from the belt with a large curvature. There may be a tip offset where the part is brought to the belt.

In order to increase the fixing strength in a high-speed machine, if the melt viscosity of the binder resin is lowered or a resin having a low molecular weight is used, the toner adheres to the carrier in the case of two-component development during long-term use, so-called spent. Is likely to occur. The stress resistance of the developer is reduced. Further, when it is used in a low-speed machine, offset easily occurs in which toner adheres to the heat roller during fixing. Further, blocking occurs in which the toner particles are fused with each other during long-term storage.

In contrast to a resin composition in which a high molecular weight component and a low molecular weight component are blended or copolymerized, a releasing agent having a low melting point, such as polyethylene or polypropylene wax, has a releasability from a heat roller at the time of fixing. It is added for the purpose of improving the offset resistance. However, it is difficult to improve the dispersibility of these release agents in the binder resin, the reverse polarity toner is likely to be generated due to poor dispersion, and fog is generated on the non-image area. Further, an image defect such as being scratched by a brush occurs at the rear end portion of the solid black image portion, which deteriorates the image quality. Further, there is a problem that the carrier, the photoconductor, and the developing sleeve are contaminated with filming.

Further, when a conventional toner having a constitution of enhancing the glossiness and translucency of a color image by using a low melting point releasing agent such as polypropylene or polyethylene and a resin having a low softening property is used, a developing roller for development is used. If the dispersibility is improved, the effect of releasability decreases and non-offset occurs due to vertical stripes on the top, poor cleaning of the transfer body and filming, and poor scraping of the transfer roller cleaning roller. The area becomes smaller and it is difficult to achieve both.

Further, in the contact type one-component developing method in which an elastic blade for regulating the toner layer is used in contact with a developing roller made of silicone or urethane and a supply roller of urethane etc. for supplying toner to the developing roller is provided, In toners to which a low-melting-point release agent is added, the charge rising property deteriorates,
Deterioration of charge retention property occurs during long-term continuous use. Further, by using the toner containing the above-mentioned low melting point release agent,
When using several thousand sheets, vertical streaks gradually occur on the developing roller, which causes image defects such as white spots and black streaks. This is damage to the developing roller due to poor dispersion of the release agent, fusion to the blade,
It is considered that the cause is agglomeration due to friction between the supply roller and the developing roller.

Further, toner having a specific particle size may be selectively developed during repeated use. This phenomenon is caused by the fact that the toner has a particle size distribution, and therefore the fluidity of each toner particle is different, the toner cohesiveness is different, or the composition is varied. If the fluidity of each toner particle is significantly different, the opportunity for triboelectric charging is different, and thus the amount of charge varies. When the toner having a specific particle size is selectively developed, the particle size distribution of the toner remaining undeveloped changes, resulting in a decrease in image density and an increase in fog. Further, the transfer efficiency is lowered, the smoothness of the image surface is lowered, and the characters are missing. Further, the gloss after fixing is deteriorated.

An image forming station having a plurality of photoconductors and developing units is arranged side by side, and an endless transfer member is brought into contact with the photoconductors to sequentially transfer toners of respective colors to the transfer unit in a primary transfer. There is a secondary transfer process in which a multi-layered transfer color toner image is formed on a transfer body by executing the process, and then the multi-layered toner image formed on the transfer body is collectively transferred onto a transfer medium such as paper or OHP. A tandem transfer system configured to be executed, or a tandem transfer system configured to continuously transfer directly to a transfer medium such as paper OHP without using a transfer body, reduces the size and speed of the machine. Therefore, it is required that the distance between the image forming stations is shorter and the printing is performed at high speed. As a result, for example, the time from the first transfer of the yellow toner to the second transfer of the next magenta toner is extremely short, and the charge relaxation of the transfer body and the charge relaxation of the transferred toner hardly occur. When the magenta toner is transferred onto the yellow toner, the magenta toner is repelled by the charge action of the yellow toner, which causes a problem of a decrease in transfer efficiency and a blank character at the time of transfer. Further, the toner of a specific particle size is selectively developed during repeated use, and if the fluidity of each toner particle is greatly different, the chances of frictional electrification are different, resulting in variations in the amount of electrification and further deterioration of transferability. Will be invited.

After the final transfer of the final toner,
When the secondary transfer is performed on the copy paper all at once, image repulsion occurs due to repulsion between the toner particles.

Further, in order to improve the dot reproducibility in the transfer, the resistance of the transfer member is made high, so that the toner image is disturbed and the tendency of the transfer failure becomes more remarkable.

Further, in order to enable oilless fixing without using oil at the time of fixing, a toner composition in which a releasing agent is added to the color toner has a strong charge retention property, and the tendency of toner image disturbance and transfer failure becomes more remarkable. Therefore, it becomes difficult to achieve both transfer and fixing.

Further, it is necessary to clean and remove the toner that remains without being transferred to the transfer material during the secondary transfer, and a rubber blade, a roller to which a bias is applied, a fur brush or the like is used. At this time, the toner to which the release agent having a low melting point is added causes filming on the intermediate transfer member. Further, when the toner removed by the cleaning roller is scraped from the roller by the metal plate, the toner is fused and adhered to the metal plate, resulting in scraping failure. In particular, by using a low-melting sharp melt resin to express the glossiness and high translucency of color images,
Filming and scraping defects are more likely to occur.

Further, it is important to realize a cleanerless process without a cleaning process in order to reduce the size of the equipment and save resources. After the toner that visualizes the electrostatic latent image formed on the photoconductor is transferred onto the transfer material by the transfer means, the toner remaining on the photoconductor is usually collected by cleaning to become waste toner. At this time, the cleanerless process performs the subsequent charging, exposure, and development processes without having a cleaning process step. First, it is essential to realize high transferability in transfer, and spheroidizing treatment of toner and improvement of transferability by polymerized toner are being performed. However, it is difficult for 100% transfer residual toner to be zero, and it remains on the photoconductor to some extent. In the next development process, if the residual toner in the non-image area is returned to development, no image problem occurs. Therefore, it is an important point to collect the toner remaining in the non-image area during development. In particular, in a toner to which a low melting point release agent is added in order to satisfy the non-offset property at the time of fixing, the fluidity tends to decrease, and the transferability is not good, and it is difficult to collect it in the development in the cleanerless process. Therefore, the memory of the previous image pattern remains in the non-image portion.

As described above, the toner must satisfy the above-mentioned problems comprehensively, and particularly in the case of an oilless fixing toner that does not use oil, the toner itself has the oil function used for the fixing member. If a release agent such as wax is used in the toner to retain the toner, a problem of chargeability arises, the charge amount fluctuates during continuous use, and the toner itself does not have a long life. However, problems such as filming on the photoconductor occur, and it is very difficult to achieve both the fixability, developability, and durability of the oilless toner.

In view of the above problems, it is an object of the present invention to provide a toner and an electrophotographic apparatus having a uniform charge distribution and capable of stabilizing an image for a long period of time.

No vertical streaks are formed on the developing roller even when used in the one-component developing method, and thermal fusion or aggregation of toner does not occur on the layer-regulating blade or the developing roller even when continuously used, thus suppressing a decrease in charge amount. Another object of the present invention is to provide a toner and an electrophotographic apparatus that can improve the dispersibility of an additive and maintain stable developability without deteriorating the resin characteristics.

An image forming station having a plurality of photoconductors and developing units is arranged side by side, and an endless transfer body is brought into contact with the photoconductors to successively transfer toners of respective colors to the transfer body in a primary transfer. There is a secondary transfer process in which a multi-layered transfer color toner image is formed on a transfer body by executing the process, and then the multi-layered toner image formed on the transfer body is collectively transferred onto a transfer medium such as paper or OHP. In a tandem type electrophotographic apparatus equipped with a transfer system configured to be executed, it is possible to prevent hollowing and scattering during transfer,
It is an object of the present invention to provide a toner and an electrophotographic apparatus that can obtain high transfer efficiency, avoid filming on a transfer body and the like, and prevent fusion to a cleaning roller.

High transfer efficiency is obtained even in the cleanerless process, the charge amount and the fluidity are not deteriorated, the memory is not generated in the development, the cleanerless process is enabled, and the environmental pollution prevention and the resource reuse are realized. It is an object of the present invention to provide a toner and an electrophotographic apparatus that enable the toner.

Another object of the present invention is to provide a full-color electrophotographic toner and an electrophotographic apparatus which exhibit high translucency and glossiness by oilless fixing without applying oil. Even with color toners that use low-melting sharp-melt resin, filming on developing rollers, doctor blades, intermediate transfer bodies, etc. can be avoided, and even during long-term use under high humidity, the photoreceptor and intermediate transfer body can be transferred. An object of the present invention is to provide a toner and an electrophotographic apparatus that can prevent filming of the body and the like.

Further, in the fixing process using a belt, and also in the belt fixing using a roller having a large fixing curvature with a low fixing pressure and a long fixing nip, the non-wrapping property of the paper on the belt is improved, Further, it is an object of the present invention to provide a toner and an electrophotographic apparatus which can prevent the leading edge of the image from being chipped when the belt and the paper are separated from each other and can achieve both development and transfer properties.

[0033]

In view of the above problems, the structure according to the present invention includes a toner image forming station including at least an image carrier, a charging unit for forming an electrostatic latent image on the image carrier, and a toner carrier. A primary transfer process for transferring a toner image having a plurality of electrostatic latent images formed on the image bearing member to the image bearing member by contacting the endless transfer member with the image bearing member. However, the secondary transfer is performed successively at four primary transfer positions to form a multi-layered transfer toner image on the transfer body, and then the multi-layered toner images formed on the transfer body are collectively transferred to a transfer medium. A transfer system configured to perform the process, wherein the transfer process comprises a distance from a first primary transfer position to a second primary transfer position, or a second primary transfer position to a third primary transfer position. Distance to transfer position , Or the fourth from the third primary transfer position
When the distance to the primary transfer position is d1 (mm) and the peripheral speed of the photoconductor is v (mm / s), d1 / v ≦ 0.65
(Sec), the electrostatic latent image formed on the image bearing member has a particle size of 2 × 10 ^{−6 to} 5 × 10 ⁻⁶ m.
Is an electrophotographic apparatus for forming a visible image with a toner containing 5 to 50% by number of particles and having a compression degree of 5 to 40% calculated from static bulk density and dynamic bulk density.

Further, the structure according to the present invention has a plurality of toner image forming stations including at least an image carrier, a charging unit for forming an electrostatic latent image on the image carrier and a toner carrier, and the image carrier. A transfer system configured to perform a transfer process of sequentially transferring a toner image, which is a visualized electrostatic latent image formed on a body, to a transfer medium at four primary transfer positions, and The transfer process comprises a distance from the first transfer position to the second transfer position, a distance from the second transfer position to the third transfer position, or a distance from the third transfer position to the fourth transfer position. Distance d1
(Mm) and the peripheral velocity of the photoconductor is v (mm / s), the structure satisfies the condition of d1 / v ≦ 0.65 (sec), and the electrostatic latent image formed on the image carrier is Image, grain size 2
It contains 5 to 50% by number of particles of × 10 ^{-6 to} 5 × 10 ^-6 m and has a compression degree of 5 to 4 calculated from the static bulk density and the dynamic bulk density.
This is an electrophotographic apparatus that visualizes a toner image with 0% toner.

The composition according to the present invention is a toner containing at least a binder resin, a colorant, a fixing aid, and an external additive, and has a number average molecular weight in the molecular weight distribution in gel permeation chromatography (GPC). 100-5000,
Weight average molecular weight of 200 to 10,000, ratio of weight average molecular weight to number average molecular weight (weight average molecular weight / number average molecular weight)
Is 1.01 to 8, the ratio of Z average molecular weight to number average molecular weight (Z
(Average molecular weight / number average molecular weight) of 1.02 to 10 and molecular weight of 5 × 10 ² to 1 × 10 ⁴ has at least one maximum molecular weight peak, iodine value of 25 or less, and saponification value of 30 to 300. 1 to 12 parts by weight with respect to 100 parts by weight of the binder resin having an acid value of 1 to 70 mgKOH / g, and a particle size of 2 × 10 ^{−6 to} 5
The toner contains 5 to 50% by number of particles of × 10 ^-6 m and has a compression degree of 5 to 40% calculated from the static bulk density and the dynamic bulk density.

Further, the structure according to the present invention has a plurality of toner image forming stations including at least an image carrier, a charging unit for forming an electrostatic latent image on the image carrier, and a toner carrier, and the image carrier. At the four primary transfer positions, a primary transfer process is performed in which a toner image obtained by visualizing an electrostatic latent image formed on a body is transferred to the transfer body by bringing an endless transfer body into contact with the image carrier. A secondary transfer process is performed in which the multi-layered transfer toner image is formed on the transfer body by sequentially performing the transfer, and then the multi-layered toner image formed on the transfer body is collectively transferred to a transfer medium. And a fixing process in which the toner transferred to the transfer medium is fixed by a fixing member that does not use release oil, and the transfer process is performed from the first primary transfer position to the second primary transfer position. The distance to the position, or the distance from the second primary transfer position to the third primary transfer position, or a distance from the third primary transfer position to the fourth primary transfer positions d1
(Mm) and the peripheral velocity of the photoconductor is v (mm / s), the structure satisfies the condition of d1 / v ≦ 0.65 (sec), and the electrostatic latent image formed on the image carrier is The image shows that the weight average molecular weight Mw is 10,000 to 300,000, the ratio Mw / Mn of the weight average molecular weight Mw and the number average molecular weight Mn is 3 to 100, and the ratio Mz / Mn of the Z average molecular weight Mz and the number average molecular weight Mn is 10 to 10. Two
000, 1/2 outflow temperature is 8 with the high flow tester
It contains a polyester resin obtained by polycondensation of a polyhydric carboxylic acid or a lower alkyl ester thereof whose polyhydric carboxylic acid whose outflow starting temperature is 80 to 120 ° C., and has a particle size of 2 × 10 ^{−6 to} 5 5 × 10 ⁻⁶ m particles
An electrophotographic apparatus for visualizing with a toner containing 50% by number and having a compression degree of 5 to 40% calculated from a static bulk density and a dynamic bulk density.

Further, the structure according to the present invention has a plurality of toner image forming stations including at least an image carrier, a charging unit for forming an electrostatic latent image on the image carrier, and a toner carrier, and the image carrier. A transfer system configured to perform a transfer process of sequentially transferring a toner image, which is a visualized electrostatic latent image formed on a body, to a transfer medium at four primary transfer positions, and the transfer medium. A fixing process for fixing the toner transferred to the toner by a fixing member that does not use release oil.
From the transfer position to the second transfer position, the distance from the second transfer position to the third transfer position, or the distance from the third transfer position to the fourth transfer position is d1 (mm),
When the peripheral speed of the photoconductor is v (mm / s), d1 / v
The structure satisfies the condition of ≦ 0.65 (sec), and the electrostatic latent image formed on the image bearing member has a weight average molecular weight Mw.
Is 10,000 to 300,000, weight average molecular weight Mw and number average molecular weight M
The ratio Mw / Mn of n is 3 to 100, the ratio Mz / Mn of the Z-average molecular weight Mz and the number-average molecular weight Mn is 10 to 2000, and the 1/2 outflow temperature by the Koka type flow tester is 80 to 150.
The polyester resin obtained by polycondensation of polyvalent carboxylic acid or its lower alkyl ester and polyhydric alcohol having a starting temperature of 80 to 120 ° C. and a particle size of 2 × 10 ^{−6 to} 5 × 10 ⁻ the particles of ⁶ m 5 to 50% by number
Contains, and has a compression degree of 5 calculated from static bulk density and dynamic bulk density.
It is an electrophotographic apparatus that visualizes with a toner of 40%.

The composition according to the present invention is a toner containing at least a binder resin, a colorant, a fixing aid, and an external additive, wherein the binder resin has a weight average molecular weight Mw of 10,000 to 30.
Mw / ratio of weight average molecular weight Mw to number average molecular weight Mn
Mn is 3 to 100, Z average molecular weight Mz and number average molecular weight M
The ratio Mz / Mn of n is 10 to 2000, the half outflow temperature by the Koka type flow tester is 80 to 150 ° C, and the outflow start temperature is 80 to 120 ° C. Contains polyester resin obtained by polycondensation with alcohol, and has a particle size of 2 × 10 ⁻⁶
The toner contains 5 to 50% by number of particles having a particle size of 5 × 10 ⁻⁶ m and a compression degree of 5 to 40% calculated from the static bulk density and the dynamic bulk density.

[0039]

DETAILED DESCRIPTION OF THE INVENTION The toner composition and the process will be described below in this order.

In the toner of this embodiment, a polyester resin is used as a binder resin, the fixing aid, the molecular weight of the polyester resin, the molecular weight of the fixing aid, the iodine value, and the saponification value are specified. By specifying the diameter and the degree of compression, the chargeability can be stabilized. In addition, it is possible to prevent toner aggregation and prevent filming on the photoconductor, transfer body, and developing roller even after continuous use for a long period of time, and suppress the occurrence of vertical streaks due to developing roller scratches and blade fusion. It becomes possible to do. High translucency and high color reproducibility in fixing can be ensured, and the offset width can be expanded to a higher temperature range without requiring fixing oil, achieving both high translucency and offset resistance. We have created a configuration that enables digital image quality and color reproduction with high color reproducibility. Further, in the high-speed color image formation of the tandem system, it is possible to suppress transfer defects such as blank areas and retransfer.

In the molecular weight distribution in GPC as the binder resin of the present embodiment, at least one maximum molecular weight peak is in the region of 2 × 10 ^{3 to} 3 × 10 ⁴ , and 3 × is a component existing in the high molecular weight region. It has a molecular weight component of 10 ⁴ or more in an amount of 5% or more with respect to the entire binder resin, and has a weight average molecular weight of 10,000 to 10,000.
300,000, Z average molecular weight 20,000 to 500,000, ratio of weight average molecular weight to number average molecular weight (weight average molecular weight / number average molecular weight) 3 to 100, ratio of Z average molecular weight to number average molecular weight (Z average molecular weight / Number average molecular weight) is 10 to 2000, the melting temperature (hereinafter softening point) by the 1/2 method by the Koka type flow tester is 80 to 150 ° C, and the outflow starting temperature is 80 to 12
It is preferable to use a polyester resin having a glass transition point of 0 ° C. and a glass transition point of the resin in the range of 45 to 68 ° C. as a component.

The weight average molecular weight is preferably 10,000 to 12
10,000, Z average molecular weight 20,000 to 300,000, weight average molecular weight / number average molecular weight 3 to 50, Z average molecular weight / number average molecular weight 10 to 1000, softening point 90 to 140 ° C., outflow starting temperature 85 to It is preferable to use a polyester resin having a glass transition point of 115 ° C. and a glass transition point of 52 to 65 ° C. as a component. More preferably, the weight average molecular weight is 10,000 to 40,000, the Z average molecular weight is 20,000 to 100,000, the weight average molecular weight / number average molecular weight is 3 to 20, and the Z average molecular weight / number average molecular weight is 10 to 1.
00, the softening point is 105 to 135 ° C, and the outflow starting temperature is 90.
It is preferable to use a polyester resin having a glass transition point of -120 ° C and a glass transition point of 58-65 ° C as a component.

Further, as a component existing in the high molecular weight region,
It is preferable to have a molecular weight component of 1 × 10 ⁵ or more in an amount of 3% or more based on the entire binder resin. Further, as a component existing in the high molecular weight region, it is preferable to have a molecular weight component of 3 × 10 ⁵ or more in an amount of 0.5% or more based on the entire binder resin.

[0044] Preferably the components present in the high molecular weight region, a 8 × 10 ⁴ ~1 × 10 ⁷ molecular weight component with respect to the entire binder resin 3% or more, and 1 × 10 ⁷ or more components does not contain The configuration is preferred.

More preferably, as a component existing in the high molecular weight region, a high molecular weight component of 3 × 10 ^{5 to} 9 × 10 ⁶ is contained in the binder resin in an amount of 1% or more, and a component of 9 × 10 ⁶ or more. Is not contained.

More preferably, as a component existing in the high molecular weight region, a high molecular weight component of 7 × 10 ^{5 to} 6 × 10 ⁶ is contained in an amount of 1% or more based on the entire binder resin, and a component of 6 × 10 ⁶ or more. Is not contained.

If the amount of the high molecular weight component is too large or if it is too large, the large molecular weight component remains during kneading, which impairs the light-transmitting property. In addition, the production efficiency of the resin itself is reduced. In addition, the developing roller and the supply roller are unnecessarily damaged to cause vertical streaks in the image. In addition, the dispersibility of the fixing aid decreases.

The binder resin has a weight average molecular weight of less than 10,000, a Z average molecular weight of less than 20,000, and a weight average molecular weight /
Number average molecular weight less than 3, Z average molecular weight / number average molecular weight less than 10, softening point less than 80 ° C, outflow starting temperature less than 80 ° C, glass transition point 45 ° C.
When it is smaller, the dispersibility at the time of kneading decreases, resulting in increased fog and poor durability. Further, the kneading stress during kneading is not sufficiently applied, and the molecular weight cannot be maintained at an appropriate value. The dispersibility of the wax and charge control agent in the resin deteriorates, and the repulsion due to the charge action of the toner is less likely to be alleviated. In addition, fog and toner scattering increase. In addition, offset resistance and high-temperature storability are deteriorated, further, cleaning failure on the transfer member and filming on the photosensitive member occur.

The binder resin has a weight average molecular weight of more than 300,000, a Z average molecular weight of more than 500,000, a weight average molecular weight / number average molecular weight of more than 100, and a Z average molecular weight /
Number average molecular weight is greater than 2000 and softening point is 150 ° C.
If the outflow starting temperature is higher than 120 ° C. and the glass transition point is higher than 68 ° C., the load during the processing of the machine becomes excessive and the productivity is extremely lowered, or the transparency of the color image is lowered. This leads to a decrease in fixing strength.

Further, the GPC of the melt-kneaded toner
Has a molecular weight distribution of 2 × 10 ^{3 to} 3 × 10 ⁴ and at least one maximum molecular weight peak in the region of 5 × 10 ⁴
It is a structure having at least one maximum peak or shoulder of the molecular weight in the region of 1 × 10 ⁶ . Preferably, the toner has at least one maximum molecular weight peak in the low molecular weight side in the region of 3 × 10 ³ to 2 × 10 ⁴ , and more preferably in the region of 4 × 10 ³ to 2 × 10 ^4. It is a structure having one.

Further, the position of the maximum molecular weight peak or shoulder existing on the high molecular weight side of the toner is 6 × 10 ^{4 to} 7
It has at least one in the region of × 10 ⁵ , and more preferably has at least one peak or shoulder of the maximum molecular weight in the region of 8 × 10 ^{4 to} 5 × 10 ⁵ .

When the maximum molecular weight peak position of the molecular weight distribution of the toner existing on the low molecular weight side is smaller than 2 × 10 ³ , the durability is deteriorated, and when it is larger than 3 × 10 ⁴ , the fixability is deteriorated and the light transmitting property is deteriorated. descend.

Further, the molecules of the toner existing on the high molecular weight side
The position of the maximum molecular weight peak or shoulder in the mass distribution is 5
× 10^FourIf it becomes smaller, the offset resistance will decrease,
Storage stability deteriorates. Deterioration of developability and waste toner recycling
The rolling property is also reduced. 1 x 10 ⁶Grindability becomes larger
Decrease, leading to a decrease in production efficiency.

Further, the content of the high molecular weight component of 5 × 10 ⁵ or more as the component existing in the high molecular weight region of the toner is preferably 10 wt% or less with respect to the entire binder resin. The large amount of components existing in the high molecular weight region of 5 × 10 ⁵ or more, or the huge state is a result of the problem that the kneading state fails because uniform kneading stress is not applied to the toner constituent materials during kneading. This significantly impairs the translucency. Also, increase in fog due to poor dispersion, developing roller,
The supply roller is damaged, the pulverizability of the toner is deteriorated, and the manufacturing efficiency is reduced.

More preferably, the content of the high molecular weight component of 5 × 10 ⁵ or more is 5% or less with respect to the entire binder resin,
More preferably, the content of the high molecular weight component of 1 × 10 ⁶ or more is 1% or less based on the entire binder resin, or the high molecular weight component is not contained.

In the molecular weight distribution in the GPC chromatogram of the toner, the height of the molecular weight distribution of the maximum molecular weight peak existing in the region of 2 × 10 ^{3 to} 3 × 10 ⁴ is Ha, 5 ×.
Letting Hb be the maximum molecular weight peak or shoulder height existing in the region of 10 ⁴ to 1 × 10 ⁶ , Hb / Ha is 0.
It is set to 15 to 0.9.

When Hb / Ha is smaller than 0.15, the offset resistance is deteriorated, the storage stability is also deteriorated, and the filming on the developing sleeve and the photoreceptor is promoted. When it is larger than 0.9, the developing roller and the supply roller are scratched, the pulverizability is deteriorated, the productivity is lowered, and the cost is increased. More preferably, Hb / Ha is 0.15 to 0.7, and even more preferably Hb / Ha is 0.2 to 0.6.

Further, in order to prevent high offset while ensuring high translucency and requiring no fixing oil, the molecular weight distribution of the toner in GPC is at least one in the region of 2 × 10 ^{3 to} 3 × 10 ⁴ . Maximum molecular weight peak, 5 × 10 ⁴
~ 1 × 10 ⁶ region having at least one peak or shoulder of the maximum molecular weight, the molecular weight of 5 × 10 ⁴ ~
Focusing on the molecular weight curve in a region larger than the molecular weight value corresponding to the maximum peak or shoulder of the molecular weight distribution existing in the region of 1 × 10 ⁶ , the height of the maximum peak or shoulder of the molecular weight distribution is 1 as a reference, When the molecular weight corresponding to a height of 90% of the peak of the molecular weight or the shoulder is M90 and the molecular weight corresponding to 10% of the height of the peak of the molecular weight or shoulder is M10, M10 / It can be realized by setting M90 to 0.5 to 8. Furthermore, (M10-M90) / M90 is 0.
It can be realized by setting 1 to 7.

The above M10 / M90, and (M10
Defining the value of (-M90) / M90 (the slope of the molecular weight distribution curve) can quantify the state of molecular cleavage of the ultrahigh molecular weight component, and this value is within the range described above (the slope of the molecular weight distribution curve. Is abrupt), the ultra-high molecular weight component that inhibits the translucency disappears due to cutting during kneading, resulting in high translucency. Further, the high molecular weight component forming a peak or shoulder appearing on the high molecular side contributes to the anti-offset property, and it is possible to prevent the offset of the color toner from occurring without using oil.

Further, when the ultra high molecular weight component is molecularly cleaved, it is possible to uniformly disperse the fixing aid and the charge control agent in the binder resin so that the charge amount becomes uniform and clear. It has resolution and does not deteriorate durability even if it is used continuously for a long period of time. In addition, the cleaning property of the intermediate transfer member is improved, vertical stripes are not generated on the developing roller, and it is possible to prevent hollow defects during transfer and to obtain highly efficient transfer property.

When the value of M10 / M90 is larger than 8 or (M10-M90) / M90 is larger than 7, the ultra-high molecular weight component still remains and impairs the translucency.
The value of M10 / M90 is smaller than 0.5, or (M1
When 0-M90) / M90 is smaller than 0.1, the mechanical load during kneading becomes excessive and the productivity decreases. Toner durability is reduced. More preferably M10 / M90
Has a value of 0.5 to 6, and (M10-M90) / M90
Is 0.1 to 4.5. More preferably, M10 /
The value of M90 is 0.5 to 4.5, and (M10-M9
0) / M90 is 0.1 to 3.5.

As a result, a developing roller for digital high image quality, high color reproducibility, and contact type one-component developing,
The supply roller can be used stably for a long period of time, and high translucency and offset resistance can be achieved without using oil for offset prevention on the fixing roller.Furthermore, a cleanerless process is realized, and in the transfer process. High transferability can be realized.

By kneading the above-mentioned binder resin with a high shearing force in the melt-kneading process, it becomes possible to exhibit the characteristics which have not been heretofore available. By fixing without using oil, it is possible to achieve both high transparency of the color toner and offset resistance. In other words, the binder resin to which the ultra-high molecular weight component has been imparted has a high shearing force, whereby the ultra-high molecular weight component is made to have a low molecular weight, thereby exhibiting high translucency. Offset property can also be satisfied. In addition, since it has an ultra-high molecular weight component, high shearing force is applied during kneading, which makes it possible to disperse the fixing aid more uniformly, improve translucency, improve non-offset properties, high image quality, and high color reproduction. Sex is obtained.

After the melt-kneading treatment, the toner has a weight average molecular weight of 8,000 to 180,000 and a Z average molecular weight of 18,000 to 45.
The weight average molecular weight to number average molecular weight ratio (weight average molecular weight / number average molecular weight) is 3 to 80, and the Z average molecular weight to number average molecular weight ratio (Z average molecular weight / number average molecular weight) is 10 to 1.
000.

By kneading the toner in this suitable range with a high shearing force, it is possible to achieve both high light transmission and offset resistance of the color toner by fixing without using oil.

Preferably the weight average molecular weight is 8000 to 1
It is preferable that the number average molecular weight is 0,000, the Z average molecular weight is 18,000 to 300,000, the weight average molecular weight / number average molecular weight is 3 to 60, and the Z average molecular weight / number average molecular weight is 10 to 500.

More preferably, the weight average molecular weight is 10,000 to
It is preferable that the weight average molecular weight is 40,000, the Z average molecular weight is 20,000 to 80,000, the weight average molecular weight / number average molecular weight is 3 to 30, and the Z average molecular weight / number average molecular weight is 10 to 50.

The weight average molecular weight is less than 8000, and Z
Average molecular weight less than 18,000, weight average molecular weight /
When the number average molecular weight is less than 3 and the Z average molecular weight / number average molecular weight is less than 10, the kneading stress is not sufficiently applied and the molecular weight cannot be maintained at an appropriate value. The dispersibility of the fixing aid decreases, resulting in poor offset resistance and high temperature storage stability.
Further, cleaning failure on the intermediate transfer member and filming on the photosensitive member occur.

When the weight average molecular weight is more than 180,000, the Z average molecular weight is more than 450,000, the weight average molecular weight / number average molecular weight is more than 80, and the Z average molecular weight / number average molecular weight is more than 1000, the shear force pressure is increased. On the contrary, internal additives such as a charge control agent coagulate with each other, leading to a decrease in dispersibility, resulting in an increase in fogging during a cleanerless process, a decrease in image density, and a transfer failure. Further, the fixing strength is lowered, and the light-transmitting property and the glossiness are lowered.

The binder resin contains 5% by weight of THF insoluble component.
Hereinafter, it is preferable that the composition has no THF-insoluble component. If the amount of the THF-insoluble component is more than 5% by weight, it becomes a factor of deteriorating the translucency of the color image, which deteriorates the image quality.

As the binder resin preferably used in this embodiment, a polyester resin obtained by polycondensation of an alcohol component and a carboxylic acid component such as carboxylic acid, carboxylic acid ester and carboxylic acid anhydride is preferably used. .

More preferred is a polyester resin obtained by polycondensation of a polyhydric alcohol and a carboxylic acid component containing an aromatic dicarboxylic acid and a trivalent or higher polycarboxylic acid or a lower alkyl ester thereof. A polyester resin obtained by polycondensation of a polyhydric alcohol and a carboxylic acid component containing an aliphatic dicarboxylic acid and a trivalent or higher polycarboxylic acid or a lower alkyl ester thereof is more preferable.

Examples of the divalent carboxylic acid or lower alkyl ester include aliphatic dibasic acids such as malonic acid, succinic acid, glutaric acid, adipic acid and hexahydrophthalic anhydride.
Maleic acid, maleic anhydride, fumaric acid, itaconic acid,
Examples thereof include aliphatic unsaturated dibasic acids such as citraconic acid, aromatic dibasic acids such as phthalic anhydride, phthalic acid, terephthalic acid, and isophthalic acid, and their methyl esters, ethyl esters, and the like. Among these, aromatic dibasic acids such as succinic acid, phthalic acid, terephthalic acid and isophthalic acid, and lower alkyl esters thereof are preferable. It is preferable to use a combination of succinic acid and terephthalic acid or phthalic acid and terephthalic acid.

The trivalent or higher carboxylic acid component is 1,
2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid,
1,2,4-naphthalene tricarboxylic acid, 1,2,4-
Butanetricarboxylic acid, 1,2,5-hexatricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, tetra (methylenecarboxyl) methane, 1,2,7,8-octanetetracarboxylic acid, Examples thereof include pyromellitic acid, enpol trimer acid, acid anhydrides thereof, and alkyl (C1-12) esters.

As the dihydric alcohol, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butylene glycol, 1,4
-Butylene glycol, 1,6-hexanediol, neopentyl glycol, diethylene glycol, dipropylene glycol, bisphenol A ethylene oxide adduct, bisphenol A propylene oxide adduct, and other diols, glycerin, trimethylolpropane, trimethylolethane, etc. Examples are triols and mixtures thereof. Among these, particularly, bisphenol A represented by (Chemical Formula 1), its derivative, its alkylene oxide adduct, neopentyl glycol,
Totimethylol propane is preferred.

[0076]

[Chemical 1]

Examples of the trihydric or higher alcohol component include sorbitol, 1,2,3,6-hexanetetrol, 1,
4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-
Butanetriol, 1,2,5-pentanetriol,
Examples thereof include glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane and 1,3,5-trihydroxymethylbenzene.

For the polymerization, known polycondensation, solution polycondensation and the like can be used. As a result, a good toner can be obtained without impairing the vinyl chloride matting resistance and the color of the color material of the color toner.

The polyhydric carboxylic acid and polyhydric alcohol are generally used in a proportion of the number of hydroxyl groups to the number of carboxyl groups (OH / COOH) of 0.8 to 1.4.

The molecular weights of the resin and toner are the values measured by gel permeation chromatography (GPC) using several kinds of monodisperse polystyrene as standard samples.

The apparatus is HPLC8120 series manufactured by Tosoh Corporation, and the column is TSKgel super HM-H H4.
000 / H3000 / H2000 (7.8 mm diameter, 15
0 mm × 3), eluent THF (tetrahydrofuran),
Flow rate 0.6 ml / min, sample concentration 0.1%, injection rate 2
0 μL, detector RI, measurement temperature 40 ° C. The pretreatment for measurement is to dissolve the sample in THF and filter with a 0.45 μm filter to measure the resin component from which additives such as silica have been removed. The measurement conditions are such that the molecular weight distribution of the target sample falls within a range in which the logarithm of the molecular weight and the count number are linear in the calibration curve obtained from several kinds of monodisperse polystyrene standard samples.

The apparatus is a GPC-15 manufactured by WATERS.
0C, column is Shodex HT-806M (8.0
mmI. D. -30 cm × 2), the eluent is o-dichlorobenzene, the flow rate is 1.0 mL / min, and the sample concentration is 0.1.
3%, injection volume 200 μL, detector RI, measurement temperature 130 ° C., measurement pretreatment 0.5 μm after dissolving sample in solvent
Alternatively, the measurement may be performed by filtering with a metal sintered filter of No.
The measurement conditions are such that the molecular weight distribution of the target sample falls within a range in which the logarithm of the molecular weight and the count number are linear in the calibration curve obtained from several kinds of monodisperse polystyrene standard samples.

The softening point of the binder resin was measured by a flow tester (CFT500) manufactured by Shimadzu Corporation while heating a 1 cm ³ sample at a heating rate of 6 ° C./min with a plunger of about 9.8 × 10 ⁵ N. / M ² load, diameter 1mm,
Extruded from a die with a length of 1 mm, the temperature at which the piston stroke begins to rise is the outflow start temperature (Tfb), the minimum value of the curve and the outflow from the relationship with the temperature rise temperature characteristic in the relationship between the piston stroke and temperature of this plunger. The half of the difference between the end points is obtained, and the temperature at the point where the difference is added to the minimum value of the curve is the melting temperature (softening point Tm) in the 1/2 method.

The glass transition temperature of the resin was measured by using a differential scanning calorimeter, and the temperature was raised to 100 ° C., left at that temperature for 3 minutes, and then cooled to room temperature at a temperature decreasing rate of 10 K / min. The temperature at the intersection of the extension line of the base line below the glass transition point and the tangent line showing the maximum slope from the rising part of the peak to the apex of the peak when the heat history is measured at 10 K / min. Say

For the melting point of the endothermic peak by DSC, a differential calorimeter DSC-50 manufactured by Shimadzu Corporation was used. 5K /
The temperature was raised to 200 ° C. for 5 minutes, rapidly kept at 10 ° C. for 5 minutes, allowed to stand for 15 minutes, then raised at 5 K / min, and determined from the endothermic (melting) peak. The amount of sample put into the cell was 10 mg ± 2 mg.

In the present embodiment, in order to control the charge of the toner and to make the oilless fixing stronger, it is also preferable to use the above-mentioned fixing aid and charge control agent in combination with the binder resin. As a preferable material, a metal salt of a salicylic acid derivative shown in Chemical formula 2 is used.

[0087]

[Chemical 2]

Further, in the present embodiment, in order to control the charge of the toner and strengthen the oilless fixing, it is also preferable to use the above-mentioned fixing aid and charge control agent in combination with the binder resin. As a preferable material,
The metal salt of the benzylic acid derivative shown in is used.

[0089]

[Chemical 3]

With this structure, a wide non-offset temperature range can be secured in oilless fixing, and image disturbance due to the charging action at the time of fixing can be prevented. This is considered to be the effect of the charge polarity of the metal salt and the functional group having the acid value of the fixing aid. In addition, it is possible to prevent the charge amount from decreasing during continuous use. Blade fusion during development can be suppressed.

The amount of addition is 100 parts by weight of the binder resin,
0.5 to 5 parts by weight is preferable. It is more preferably 1 to 4 parts by weight, and further preferably 3 to 4 parts by weight. If the amount is less than 0.5 parts by weight, the charging effect is lost. If it is more than 5 parts by weight, color turbidity in a color image becomes noticeable.

As the pigment used in this embodiment,
Carbon black, iron black, graphite, nigrosine,
A metal complex of an azo dye, C.I. I. Pigment Yellow 180, a benzimidazolone type yellow pigment, C.I. I. Pigment Yellow 1,3,74,97,98 and the like, acetoacetic acid arylamide monoazo yellow pigments, C.I. I. Pigment Yellow 12, 13, 14, 17 and the like, acetoacetic acid arylamide disazo yellow pigments, C.I. I. Solvent Yellow 19, 77, 79, C.I. I. Disperse Yellow 164, C.I. I. Pigment Red 4
8,49: 1, 53: 1, 57, 57: 1, 81, 12
Red pigments such as 2, 5 and C.I. I. Solvent Red 4
Red dyes such as 9,52,58,8, C.I. I. Pigment Blue 15: 3 and other phthalocyanines and their blue derivative pigments are blended in one kind or two or more kinds. The addition amount is preferably 3 to 8 parts by weight with respect to 100 parts by weight of the binder resin.

Further, in this embodiment, it is preferable that the fixing aid is added to the binder resin. In fixing, a binder resin having a small amount of high molecular weight components and a narrow molecular weight distribution and a narrow softening property and a low softening property has been used so far in order to improve color fixing ability. With this configuration, it is possible to ensure the translucency, but it is necessary to apply oil to the fixing roller because offset occurs. Further, in order to realize oilless fixing, it is difficult to disperse the release agent, the pigment, the charge control agent, etc. in the configuration in which the release agent is added to the sharp-melting and low-softening binder resin,
Problems such as deterioration of transferability due to fog and poor charging, deterioration of cleaning performance, filming on a photoreceptor and a developing roller, deterioration of rising of charging, and fluctuation of image density due to charging fluctuation during repeated use occurred. With the conventional mold releasability, it is difficult to disperse in a polyester resin, image quality such as fog is deteriorated, and color toner causes color turbidity, and clear light transmission cannot be obtained.

The toner of the present embodiment makes it possible to achieve these various electrophotographic characteristics at the same time. By adding a fixing aid, fixing characteristics, particularly non-offset property in oilless fixing, high glossiness, and high translucency can be exhibited, and high temperature storage stability is not deteriorated. Even if a fluorine-based or silicon-based member is used for the fixing roller, halftone offset can be prevented. Furthermore, charging stability during continuous use can be obtained, and both fixing property and developing charging stability can be achieved.

Furthermore, by improving the state of dispersion when this is added to the binder resin, the releasability, the fixing property such as translucency, and the developability such as charge stabilization can be further improved. It may be considered that the dispersibility of other internal additives may be reduced by the addition of a release agent, but the composition of the additive of the present embodiment does not reduce the dispersibility of both of them and seeks to achieve both the fixability and the developability. be able to.

As the fixing aid, a wax having a iodine value of 25 or less and a saponification value of 30 to 300 is used, and a binder resin 100 having an acid value of 1 to 70 mgKOH / g is used.
By adding 1 to 12 parts by weight with respect to parts by weight, repulsion due to the charge action of the toner is alleviated at the time of toner multi-layer transfer in the primary transfer, and the transfer efficiency is reduced, the characters are missing in the characters at the time of transfer, and the image disturbance is suppressed. be able to.

As the wax, an ester wax composed of a higher fatty acid, a higher alcohol and an ester bond is preferably used, and a wax having a melting point of 50 to 100 ° C. by the DSC method is preferable. More preferably, the iodine value is 15 or less, the saponification value is 50 to 250, and the melting point by the DSC method is 55 to 90.
C., more preferably, the iodine value is 5 or less, the saponification value is 70 to 200, and the melting point by the DSC method is 60 to 85.degree.

When the iodine value is larger than 25, the repulsion due to the charge effect of the toner is less likely to be alleviated during the toner multi-layer transfer in the primary transfer. When the saponification value becomes smaller than 30,
The presence of unsaponifiable substances and hydrocarbons increases, causing filming of the photoconductor and deterioration of chargeability. Further, the dispersibility with the charge control agent becomes poor, which causes filming, fusion, and deterioration of the charging property during continuous use. When it is more than 300, the dispersibility of the wax in the resin is deteriorated, and the repulsion due to the charge action of the toner is less likely to be alleviated. In addition, fog and toner scattering increase. When the resin acid value is smaller than 1 mgKOH / g, the repulsion due to the charge effect of the toner is less likely to be alleviated during the toner multi-layer transfer in the primary transfer. Resin acid value is 70mg
When it is higher than KOH / g, the environmental resistance is deteriorated and the fogging is increased. If the addition amount is less than 1 part by weight with respect to 100 parts by weight of the binder resin, the effect of fixing does not appear. When the addition amount is more than 12 parts by weight with respect to 100 parts by weight of the binder resin, storage stability and transferability deteriorate.

Further, as a fixing aid, G is used in the molecular weight distribution in gel permeation chromatography (GPC).
In the molecular weight of PC, the number average molecular weight is 100 to
5000, weight average molecular weight is 200 to 10,000, ratio of weight average molecular weight to number average molecular weight (weight average molecular weight / number average molecular weight) is 1.01 to 8, ratio of Z average molecular weight to number average molecular weight (Z average molecular weight / number Average molecular weight) is 1.02-1
A polymer having at least one peak of molecular weight in the region of 0 and a molecular weight of 5 × 10 ² to 1 × 10 ⁴ is preferable. More preferably, the number average molecular weight is 500 to 4500, the weight average molecular weight is 600 to 9000, and the ratio of the weight average molecular weight to the number average molecular weight (weight average molecular weight / number average molecular weight) is 1.01.
7. Ratio of Z average molecular weight and number average molecular weight (Z average molecular weight /
Number average molecular weight) is 1.02 to 9, more preferably number average molecular weight is 700 to 4000, and weight average molecular weight is 800.
~ 8000, the ratio of the weight average molecular weight to the number average molecular weight (weight average molecular weight / number average molecular weight) is 1.06, and the ratio of the Z average molecular weight to the number average molecular weight (Z average molecular weight / number average molecular weight) is 1.02. ~ 8.

The number average molecular weight is less than 100, the weight average molecular weight is less than 200, and the ratio of the weight average molecular weight to the number average molecular weight (weight average molecular weight / number average molecular weight) is 1.0.
If it is less than 1 and the ratio of the Z average molecular weight to the number average molecular weight (Z average molecular weight / number average molecular weight) is less than 1.02, the storage stability deteriorates. Fixing offset property deteriorates. When the maximum molecular weight peak is located in a range smaller than 5 × 10 ² , the dispersibility of the charge control agent as well as the fixing aid deteriorates. The storage stability of the toner is deteriorated, filming on the photoconductor and the transfer body, vertical streaks on the developing roller, scraping failure on the cleaning roller, and the like occur.

The number average molecular weight is more than 5,000, the weight average molecular weight is more than 10,000, the ratio of the weight average molecular weight to the number average molecular weight (weight average molecular weight / number average molecular weight) is more than 8, and the Z average molecular weight and the number average molecular weight are When the ratio (Z average molecular weight / number average molecular weight) is larger than 10 and the maximum molecular weight peak is located in a range larger than the region of 1 × 10 ⁴ , the releasing action becomes weak, and the fixing property, offset resistance, etc. The fixability function deteriorates.

Further, a material having a volume increase rate of 2 to 30% when the temperature changes by 10 ° C. at a temperature equal to or higher than the melting point is preferable. When it changes from solid to liquid, it expands rapidly, and when it fuses with the heat of fixing, the adhesion between toners is further strengthened, the fixing property is further improved, and the releasability from the fixing roller is also improved. The offset property is also improved. When it is less than 2, the effect is small, and when it is more than 30, the dispersibility at the time of kneading decreases.

The heating loss of the wax at 220 ° C. is preferably 8% by weight or less. When the heating loss is more than 8% by weight, it remains in the binder resin during heating and kneading, greatly lowering the glass transition point of the binder resin and impairing the storage stability of the toner. It adversely affects the developing characteristics and causes fogging and filming of the photoconductor intermediate transfer member.

As fixing aids, meadowfoam oil derivatives, carnauba wax, jojoba oil derivatives, wax, beeswax, ozokerite, carnauba wax, candelia wax, montan wax, ceresin wax,
Materials such as natural waxes such as rice wax, synthetic waxes such as Fischer-Tropsch wax, derivatives of hydroxystearic acid, polyhydric alcohol fatty acid esters such as glycerin fatty acid ester, glycol fatty acid ester, sorbitan fatty acid ester and the like are preferable, and one kind or It is also possible to use two or more kinds in combination.

As derivatives of hydroxystearic acid, methyl 12-hydroxystearate, butyl 12-hydroxystearate, propylene glycol = mono 12-hydroxystearate, glycerin = mono 1
2-Hydroxystearate, ethylene glycol = mono-12-hydroxystearate and the like are suitable materials.

As the glycerin fatty acid ester, glycerin = monotristearate and glycerin = docosanoate are suitable materials.

Preferred glycol fatty acid esters are propylene glycol = monopalmitate, propylene glycol = monostearate and other propylene glycol fatty acid esters, and ethylene glycol = monostearate and other ethylene glycol fatty acid esters.

As the sorbitan fatty acid ester, sorbitan = monopalmitate, sorbitan = monostearate and sorbitan = monotristearate are preferable materials. Furthermore, materials such as a stearic acid ester of pentaerythritol and a mixed ester of adipic acid and stearic acid or oleic acid are preferable, and one kind or a combination of two or more kinds can be used.

Meadow foam oil derivatives include meadow foam oil fatty acids, metal salts of meadow foam oil fatty acids,
Meadow foam oil fatty acid ester, hydrogenated meadow foam oil, meadow foam oil amide, homo meadow foam oil amide, meadow foam oil triester, epoxidized maleic acid derivative of meadow foam oil, isocyanate polymerization of meadow foam oil fatty acid polyhydric alcohol ester , A halogenated modified meadow foam oil is a preferred material. These can be used alone or in combination of two or more.

The meadowfoam oil fatty acid obtained by saponification of meadowfoam oil consists of fatty acids having 18 to 22 carbon atoms. The metal salts are sodium, potassium, calcium, magnesium, barium, zinc,
Metal salts such as lead, manganese, iron, nickel, cobalt and aluminum can be used.

Meadow foam oil fatty acid ester is, for example, an ester such as methyl, ethyl, butyl, glycerin, pentaerythritol, polypropylene glycol, trimethylolpropane, and the like. Particularly, meadow foam oil fatty acid pentaerythritol monoester, meadow foam oil fatty acid Pentaerythritol triester, meadowfoam oil fatty acid trimethylolpropane ester and the like are preferable.

Further, the esterification reaction product of the meadowfoam oil fatty acid and the polyhydric alcohol such as glycerin, pentaerythritol and trimethylolpropane is treated with tolylene diisocyanate (TDI), diphenylmethane-
An isocyanate polymer of a meadow foam oil fatty acid polyhydric alcohol ester obtained by crosslinking with an isocyanate such as 4,4′-diisocyanate (MDI) can also be preferably used.

Hydrogenated meadowfoam oil is obtained by hydrogenating meadowfoam oil to convert unsaturated bonds into saturated bonds.

The meadowfoam oil amide is obtained by hydrolyzing meadowfoam oil and then esterifying it to give a fatty acid methyl ester, which is then reacted with a mixture of concentrated aqueous ammonia and ammonium chloride. Further, by adding hydrogen to this, the melting point can be adjusted. It is also possible to add hydrogen before hydrolysis. A product having a melting point of 75 to 120 ° C. is obtained. Homo-meadow foam oil amide is obtained by hydrolyzing meadow-foam oil, reducing it to alcohol, and then passing through nitril.

Examples of jojoba oil derivatives include jojoba oil fatty acid, metal salts of jojoba oil fatty acid, jojoba oil fatty acid ester, hydrogenated jojoba oil, jojoba oil amide, homojojoba oil amide, jojoba oil triester, and maleic acid of epoxidized jojoba oil. Derivatives, an isocyanate polymer of jojoba oil fatty acid polyhydric alcohol ester, and halogenated modified jojoba oil are preferred materials. These can be used alone or in combination of two or more.

The jojoba oil fatty acid obtained by saponification of jojoba oil comprises fatty acids having 18 to 22 carbon atoms. The metal salts are sodium, potassium, calcium, magnesium, barium, zinc, lead, manganese,
Metal salts such as iron, nickel, cobalt and aluminum can be used.

Examples of jojoba oil fatty acid esters include:
Esters such as methyl, ethyl, butyl and glycerin, pentaerythritol, polypropylene glycol, and trimethylolpropane, especially jojoba oil fatty acid pentaerythritol monoester, jojoba oil fatty acid pentaerythritol triester, jojoba oil fatty acid trimethylolpropane ester, etc. preferable.

In addition, jojoba oil fatty acid and glycerin,
An esterification reaction product with a polyhydric alcohol such as pentaerythritol or trimethylolpropane is converted into tolylene diisocyanate (TDI), diphenylmethane-4,4′-
An isocyanate polymer of jojoba oil fatty acid polyhydric alcohol ester obtained by crosslinking with an isocyanate such as disisocyanate (MDI) can also be preferably used. Hydrogenated jojoba oil is obtained by hydrogenating jojoba oil to convert unsaturated bonds into saturated bonds.

Jojoba oil amide is obtained by hydrolyzing jojoba oil and then esterifying it to give a fatty acid methyl ester, which is then reacted with a mixture of concentrated aqueous ammonia and ammonium chloride. Further, by adding hydrogen to this, the melting point can be adjusted. It is also possible to add hydrogen before hydrolysis. Melting point is 75
The thing of -120 degreeC is obtained. Homo jojoba oil amide is obtained by hydrolyzing jojoba oil, reducing it to alcohol, and then passing through nitrile.

Particularly preferred wax is carnauba wax having a melting point of 76 to 90 ° C. according to the DSC method, 66 to
At least one selected from the group consisting of 80 ° C. candelilla wax, 64-78 ° C. hydrogenated jojoba oil, 64-78 ° C. hydrogenated meadow foam oil, or 74-90 ° C. rice wax; Two or more waxes are preferred.

Saponification number refers to the number of milligrams of potassium hydroxide KOH required to saponify 1 g of a sample. It is the sum of acid value and ester value. To measure the saponification value, the sample is saponified in an alcoholic solution of about 0.5N potassium hydroxide and then the excess potassium hydroxide is titrated with 0.5N hydrochloric acid.

The iodine value means the amount of halogen absorbed when halogen is applied to the sample, converted into iodine and expressed in g per 100 g of the sample. Fat 100
It is the number of grams of iodine absorbed in g, and the larger this value is, the higher the degree of unsaturation of the fatty acid in the sample is. Iodine and mercury (II) chloride alcohol solution or iodine chloride glacial acetic acid solution was added to chloroform or carbon tetrachloride solution of the sample, and iodine left unreacted after standing was titrated with sodium thiosulfate standard solution to absorb iodine. Calculate the amount.

The weight loss of the sample cell was measured at
Weigh accurately up to mg (W1mg) and sample 10 to 15m
g, and weigh accurately to 0.1 mg (W2 mg). The sample cell is set on a differential thermal balance, the weighing sensitivity is set to 5 mg, and measurement is started. The temperature is controlled by the following program. After the measurement, the weight loss at the time when the sample temperature reached 220 ° C. is read to 0.1 mg (W3 mg) on the chart. The equipment is TGD-3000 manufactured by Vacuum Riko Co., Ltd., and the temperature rising rate is 10 ° C.
/ Min, maximum temperature 220 ° C, holding time 1 min, heating loss is W3 / (W2-W1) x 100 (%)
It is calculated by.

Further, the dispersion average particle diameter of the wax in the binder resin is 0.1 to 1.5 μm, and the dispersion particle diameter distribution is 0.1.
30% by number or less of particles less than μm, 0.1 to 2.0 μm
65% by number or more, and particles exceeding 2.0 μm are 5
It is preferably not more than a few percent. The particle size and the number thereof are counted from the cross-sectional photograph of the toner by TEM.

The dispersion average particle diameter is smaller than 0.1 μm,
When the number of particles of less than 0.1 μm is more than 30% by number, the releasing effect as a releasing agent is small and the fixing ability cannot be exhibited. Dispersion average particle size is greater than 1.5 μm, 2.0 μ
When the number of particles exceeding m is more than 5% by number, the dispersibility of the wax in the resin is deteriorated and the repulsion due to the charge action of the toner is less likely to be alleviated. In addition, fog and toner scattering increase.

Further, in the present embodiment, as an external additive, fine powder of metal oxide such as silica, alumina, titania, zirconia, magnesia, ferrite, magnetite, titanate such as barium titanate, calcium titanate, strontium titanate, etc., Zirconates such as barium zirconate, calcium zirconate, and strontium zirconate, or mixtures thereof are used. The external additive is hydrophobized if necessary.

The inorganic fine powder having a positive electrode charging property is treated with aminosilane, amino-modified silicone oil or epoxy-modified silicone oil. Further, in order to enhance the hydrophobic treatment, it is preferable to use a combination of treatments with hexamethyldisilazane, dimethyldichlorosilane and other silicone oils. For example, it is preferable to treat with at least one of dimethyl silicone oil, methylphenyl silicone oil, and alkyl-modified silicone oil.

As the silane coupling agent,
Dimethyldichlorosilane, trimethylchlorosilane, allyldimethylchlorosilane, hexamethyldisilazane,
Allylphenyldichlorosilane, benzylmethylchlorosilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, divinylchlorosilane, dimethylvinylchlorosilane, and the like. The silane coupling agent treatment is a dry treatment of reacting a vaporized silane coupling agent with a fine powder made into a cloud by stirring or the like, or a wet treatment of dropping a silane coupling agent in which fine powder is dispersed in a solvent. It is processed according to the law.

As the inorganic fine powder having a negative electrode charging property, those treated with a silicone oil such as dimethyl silicone oil, methylphenyl silicone oil, fluorine-modified silicone oil and alkyl-modified silicone oil are preferably used.

The treatment is carried out by mixing the inorganic fine powder and a material such as silicone oil with a mixer such as a Henschel mixer, spraying the silicone oil material onto silica, or dissolving the silicone oil material in a solvent. After dispersing, mixing with fine silica powder, and then removing the solvent to prepare. It is preferable to add 0.1 to 10 parts by weight of the silicone oil-based material to 100 parts by weight of the inorganic fine powder.

At this time, the inorganic fine powder is B due to nitrogen adsorption.
ET specific surface area is 5-300 m²/ G is preferred. Better
A good specific surface area is 10 to 250 m²/ G, more preferred
20 to 150 m²It is preferably in the range of / g.
Specific surface area is 5m²If less than / g, the fluidity of the toner
It does not improve and the storage stability decreases. Specific surface area is 300m
²If it is larger than / g, the agglomeration will worsen and uniform external additive treatment will be possible.
It gets harder. In addition, it is easy to induce filming on the photoconductor
Become 0.1 to 100 parts by weight of toner base particles
5 parts by weight, preferably 0.2 to 3 parts by weight is blended.
If it is less than 0.1 parts by weight, the fluidity of the toner cannot be improved,
If it is more than 5 parts by weight, the amount of floating silica increases and the inside of the machine is contaminated.
To do.

The toner of this embodiment is prepared through the steps of premixing, melt-kneading, pulverizing and classifying, and external addition.

The premixing treatment is a treatment for uniformly dispersing the binder resin and the additive to be dispersed therein by a mixer equipped with a stirring blade. As the mixer, a known mixer such as a super mixer (manufactured by Kawada Manufacturing Co., Ltd.), a Henschel mixer (manufactured by Mitsui Miike Kogyo), a PS mixer (manufactured by Shinko Pantech), or a Redige mixer is used.

As the melt-kneading treatment, the kneading method using a high shearing force can improve the dispersibility, and the characteristics such as the fixing property, the developing property and the durability can be improved. Specifically, it has two rolls facing each other that rotate in different directions and can be heated or cooled, and a roll temperature of one roll (RL1) and a roll temperature of the other roll (RL2) have a temperature difference. It can be realized by providing and kneading between the two rolls by rotating the rolls (RL1) and (RL2) at different peripheral speeds. Further, one roll (RL1) has a temperature difference between the front half and the rear half.

Then, the temperature setting and temperature gradient of the roll, the kneading conditions of the number of rotations and the load current, the softening point of the binder resin, the melting point of the fixing aid, and the addition amount are improved under the optimum conditions.

The rotation speed ratio of the two rolls was 1.1 to 2.
By performing the mixing in a range of 5 times, an appropriate shearing force is generated at the time of kneading, the molecular cutting of the binder resin, the dispersibility of internal additives such as colorants are improved, and the fixability and the developability are improved. It is configured to increase the rotation ratio of the roll on the side where the toner is heated to melt and wind the toner. When it is less than 1.1 times, an appropriate shearing force is not generated, the dispersibility is not improved, and the translucency is deteriorated. On the other hand, when it is more than 2.5 times, the productivity is drastically lowered, the dispersibility is not improved, and the developability is deteriorated.

At this time, by kneading under a condition that the ratio of the load current values applied to the two rolls is in the range of 1.25 to 10, an appropriate shearing force is applied and the dispersibility of the internal additive is further improved. Is improved. If it is smaller than this range, the dispersibility is not improved and the light-transmitting property is deteriorated. Also, the productivity is reduced. On the other hand, if it is larger than this range, the load applied to the roller becomes too large, and the ultra-high molecular weight component becomes too low in molecular weight, so that the non-offset property deteriorates and offset occurs.

Further, the uniformity of dispersion can be further improved, and high transferability and developability can be improved. Further, the characteristics under high temperature and high humidity and under low temperature and low humidity can be stabilized.

FIG. 1 is a schematic perspective view of the toner melt-kneading process, FIG. 2 is a plan view, FIG. 3 is a front view, and FIG. 4 is a side view. Reference numeral 601 denotes a toner raw material quantitative feeder, 602 a roll (RL1), 603 a roll (RL2), 604 a molten film of toner wound around the roll (RL1), 602-
Reference numeral 1 denotes the first half of the roll (RL1) (upstream in the raw material transport direction), 602-2 denotes the second half of the roll (RL2) (downstream in the raw material transport direction), and 605 denotes the first half of the roll (RL1) 602. Inlet of heat carrier for heating -1; 606
Is an outlet of the heat medium that has heated the front half 602-1 of the roll (RL1), and 607 is the rear half 602 of the roll (RL1).
-2 for heating or cooling the medium, 608 for heating or cooling the latter half 602-2 of the roll (RL1), 609 for heating or cooling the roll (RL2) 603 A medium inlet, 610 is a medium outlet for heating or cooling the roll (RL2) 603, 6
11 is a spiral groove on the surface of the roll, the depth is 2 to 10
Approximately mm, 612 is a toner pool formed between the rolls. The spiral groove 611 is preferable so that the material can be smoothly conveyed from the right end of the raw material input part to the left end of the discharge part when the toner is kneaded.

The toner raw material is fed with an arrow 615 from the opening 614 while passing through the raw material supply feeder 613 from the constant quantity feeder.
As described above, the roll (RL1) is dropped near the end on the side of 602-1. The length of the feed feeder opening is represented by 616. This length is preferably 1/2 to 4 times the roll radius. If the length is short, the amount of material falling down from the gap between the two rollers increases rapidly before the material to be dropped melts. If it is too long, the raw material will be separated during the transportation by the raw material feeder and uniform dispersion cannot be obtained.

Further, as shown by the arrow in FIG. 4, the drop position is dropped to a point in the range of 20 ° to 80 ° from the point where the two rolls of the roll (RL1) 602 are closest to each other. Two
If the angle is smaller than 0 °, the amount dropped from the gap between the two rolls increases rapidly. If it is more than 80 °, the toner powder will fly up a lot when it is dropped, and the surroundings will be contaminated. Further, the cover 617 is installed so as to cover an area wider than the opening length 616. Illustration of the cover is omitted in FIG.

The toner raw material from the constant quantity feeder 601 falls through the opening 614 while passing through the feed feeder 613. The toner raw material that fell is roll (RL1) 602-1
It is dropped near the end on the side. Then, the resin is melted by the heat of 602-1 and the compressive shearing force of the roll (RL2) 603, and the resin is wound around the front half portion 602-1 of the roll (RL1). That state is the second half 602 of the roll (RL1).
-Extend to the end of -2, the first half 6 of the roll (RL1)
The toner is peeled off from the latter half 602-2 of the roll (RL2) heated or cooled at a temperature lower than 02-1. The roll 603 is cooled to room temperature or lower during the above process. The clearance between the roll (RL1) 602 and the roll (RL2) 603 is 0.1 to 0.9 mm.
Is. In this embodiment, the amount of raw material charged is 15 kg / h, the diameter of the rolls (RL1) (RL2) is 140 mm, and the length is 8
It was performed at 00 mm.

The obtained toner lumps are roughly pulverized by a cutter mill or the like, and then finely pulverized by a jet mill pulverization (for example, IDS pulverizer, Nippon Pneumatic Mfg. Co., Ltd.),
Further, if necessary, fine powder particles are cut by an airflow classifier to obtain toner particles (toner base particles) having a desired particle size distribution. Then, by classification, toner particles (toner base particles) having a volume average particle diameter in the range of 3 to 6 μm are obtained.

The external addition treatment is a treatment in which an external additive such as silica is mixed with the toner particles (toner base particles) obtained by the classification. A known mixer such as a Henschel mixer or a super mixer is used for this.

Furthermore, the volume average particle diameter of the toner is 4 to 9 μm.
m, preferably 4-8 μm, more preferably 4-6 μm
m. If it is larger than 9 μm, the resolution is lowered and a high image quality cannot be obtained. If it is smaller than 4 μm, the aggregation of the toner becomes strong and the background fog increases.

The coefficient of variation of the volume particle size distribution of the toner is 1
It is preferable that the coefficient of variation of the number particle size distribution is 5 to 35% and the number particle size distribution is 20 to 40%. More preferably, the variation coefficient of volume particle size distribution is 15 to 30%, and the variation coefficient of number particle size distribution is 2.
0 to 35%, more preferably, the variation coefficient of volume particle size distribution is 15 to 25%, and the variation coefficient of number particle size distribution is 20 to 3
It is 0%.

The coefficient of variation is the standard deviation in the toner particle size divided by the average particle size. It is based on the particle size measured using a Coulter counter (Coulter Co.). The standard deviation is the square of the difference from the average value of the measured values (n-
It is expressed as the square root of the value divided by 1).

That is, the coefficient of variation refers to the extent of spread of the particle size distribution, and the coefficient of variation of the volume particle size distribution is 15%.
When the coefficient of variation of the number particle size distribution is less than 20% or less than 20%, it is difficult to be produced and the cost is increased.
If the variation coefficient of the volume particle size distribution is more than 35% or the variation coefficient of the number particle size distribution is more than 40%, the cohesiveness of the toner becomes strong when the particle size distribution becomes broad, and filming and transfer to the photoconductor are performed. Defective, it becomes difficult to collect the residual toner in the cleaning process.

In the toner particle size distribution, the particle size is 2 ×
It is preferable to contain 5 to 50% by number of particles of 10 ^{−6 to} 5 × 10 ⁻⁶ m. The fine powder in the toner affects the fluidity of the toner, the image quality, the storage stability, the filming on the photosensitive member, the developing roller, and the transfer member, the characteristics over time, the transfer property, particularly the multi-layer transfer property in the tandem system. Furthermore, it affects the non-offset property, glossiness, and translucency in oilless fixing. In a toner containing a release agent such as wax to realize oilless fixing, the amount of fine powder affects the compatibility with tandem transferability.

When the amount of fine powder is excessively large, the undispersed wax increases the exposure of the toner surface, and filming occurs on the photosensitive member, the developing roller and the transfer member. Further, since the fine powder has a large adhesion to the heat roller, it tends to be offset. Further, in the tandem system, toner aggregation is likely to be strong, and a transfer failure of the second color is likely to occur during multi-layer transfer. When the amount of fine powder decreases, the image quality deteriorates.

The amount of fine powder can be controlled by a mechanical classification method in which the centrifugal force of the rotor is used in the classification step, or an air flow type classification method in which a vortex flow is generated by intake air and the centrifugal force is applied to the toner particles. A multi-stage classification device utilizing the Coanda effect can also be used. This is because the toner particles can be satisfactorily dispersed in the fine powder classifying step, and thus the classification accuracy of the ultrafine toner and the free matter is improved.

Particle size distribution is measured by Coulter counter TA
-Using a type II (Coulter Counter), an interface (manufactured by Nikkaki) that outputs the number distribution and volume distribution and a personal computer are connected to perform measurement. An electrolyte solution containing a surfactant (sodium lauryl sulfate) at a concentration of 1% was added to about 50 ml of toner to be measured, and 2 mg of toner was measured.
Add about 3 times, and the electrolyte with the sample suspended is about 3
A dispersion treatment was carried out for a minute, and an aperture of 70 × 10 ⁻⁶ m was used with a Coulter counter TA-II type. The aperture system 70 × 10 ^-6 m, but the particle size distribution measurement range is ^{1.26 × 10 -6 m~50.8 × 10 -6} m, 2.0 × 10 -6 area of less than m outpatient It is not practical because measurement accuracy and measurement reproducibility are low due to the influence of noise and the like. Therefore, the measurement area is 2.0 × 10 ⁻⁶ m to 50.8 × 1
It was set to 0 ^-6 m. In this area, the toner volume average particle diameter Dv and 2
It was calculated toner number% of ^{× 10 -6 m~5 × 10 -6 m} .
The volume average particle diameter Dc of the carrier was measured by using Microtrac of Nikkiso Co., Ltd.

The degree of compression is calculated from the static bulk density and the dynamic bulk density, which is one of the indexes of the toner fluidity. The fluidity of the toner is affected by the particle size distribution of the toner, the toner particle shape, the external additive, and the type and amount of the wax. If the toner particle size distribution is narrow and the amount of fine powder is small, the toner surface has few irregularities and the shape is close to a sphere, the external additive amount is large, and the external additive particle size is small, the degree of compression is small. The fluidity of the toner becomes high. The degree of compression is preferably 5 to 40%. More preferably, it is 10 to 30%. Oilless fixing,
It is possible to achieve compatibility with the tanden system multi-layer transfer. If it is less than 5%, the fixability tends to be low, and particularly the light-transmitting property tends to deteriorate. Toner scattering tends to increase from the developing roller. If the transferability is higher than 40%, the transferability is deteriorated, and hollowing and transfer failure occur in the tandem system.

The carrier used in the two-component development is prepared by providing a resin coating layer on the surface of ferrite particles. The main material of the ferrite is Fe ₂ O ₃ and NiO, CuO, CoO, MgO, ZnO, MnC.
O ₃ , BaCO ₃ , and SrCO ₃ are mixed and used as a raw material.
The ferrite particles are prepared by a wet method or a dry method, and the dry method is preferable. In the dry method, the raw materials are mixed and then calcined,
It is pulverized in water by a ball mill or the like, and polyvinyl alcohol, a defoaming agent and a dispersant are further added as a binder to prepare a granulating chiller. The chiller is granulated while being dried by heating with a spray dryer, and is then subjected to main firing. Main firing is 900
It is performed at ˜1400 ° C. for 10 to 30 hours, and then crushed and classified to obtain ferrite particles.

For the coating layer, known methods such as a spray method and a dipping method are used. The coating amount is 0.3 to 1.2 wt% of the carrier particle weight.

The resin used for the resin coating layer is a fluorine resin or a silicone resin. As the carbon black contained in the resin coating layer, carbon blacks produced by various production methods are used, and oil furnace carbon acetylene black is preferable. The average particle size of the carrier is 4
It is preferably 0 to 100 × 10 ⁻⁶ m. When the average particle size of the carrier is less than 40 × 10 ⁻⁶ m, the carrier is easily developed on the photoreceptor, and the average particle size of the carrier is 100 × 10 ⁻⁶ m.
If it becomes larger, the toner holding power of the carrier becomes weaker, so that toner scattering occurs.

Further, in order to form a color image at high speed, this embodiment has a plurality of toner image forming stations including a photoconductor, a charging means and a toner carrier, and an electrostatic latent image formed on the image carrier. A primary transfer process in which an endless transfer member is brought into contact with the image carrier to transfer the visualized toner image to the transfer member is continuously executed in sequence, and a multi-layer transfer is performed on the transfer member. In a transfer process configured to perform a secondary transfer process of forming a toner image and then collectively transferring the multilayer toner images formed on the transfer body to a transfer medium such as paper or OHP, The distance from the first primary transfer position to the second primary transfer position is d1 (m
m), when the peripheral speed of the photoconductor is v (mm / s), d
The configuration is such that 1 / v ≦ 0.65 (sec) is set, and for example, the time from the primary transfer of the first color yellow toner to the primary transfer of the second color magenta toner. Is very short, charge relaxation of the transfer body or charge relaxation of the transferred toner hardly occurs, and when the magenta toner is transferred onto the yellow toner, the magenta toner is repelled by the charge action of the yellow toner, and the transfer efficiency is improved. There is a problem that the characters are dropped or characters are missing during transfer.
Further, during the primary transfer of the cyan toner of the third color, when the toner is transferred onto the previous yellow and magenta toners, the scattering of the cyan toner, the transfer failure, and the omission of transfer occur remarkably. Further, the toner of a specific particle size is selectively developed during repeated use, and if the fluidity of each toner particle is greatly different, the chances of frictional electrification are different, resulting in variations in the amount of electrification and further deterioration of transferability. Will be invited.

Further, the distance from the primary transfer position of the fourth color of the last black toner to the secondary transfer position is d2 (m
m), when the peripheral speed of the photoconductor is v (mm / s), d
In the transfer position configuration where 2 / v ≧ 0.75 (sec),
When the secondary transfer is performed on the copy paper all at once, image repulsion occurs due to repulsion between the toner particles.

Therefore, by adopting the toner constitution of the present embodiment, it is possible to prevent the transfer efficiency from being lowered and the character dropout at the time of transfer without sacrificing the fixing characteristic.

It is considered that this is because the internal additive such as wax in the resin is uniformly dispersed, the charge distribution is stabilized, the overcharge of the toner on the supply roller can be suppressed, and the fluidity fluctuation can be suppressed.

Further, in the developing process of this embodiment, an elastic blade such as rubber or metal is brought into contact with an elastic or rigid developing roller at a constant pressure to form a thin layer of toner so as to contact or not contact with the photoreceptor. It is configured to develop by contact. As a one-component developing method, a sponge-type supply roller made of urethane resin and a developing roller made of silicon resin or urethane resin are brought into contact with each other at a constant biting amount,
Toner is supplied from the supply roller to the developing roller, and an elastic rubber or metallic stainless steel doctor blade is brought into contact with the developing roller, or the metallic roller is rotated and brought into contact with the developing roller in the same direction. A developing method is preferably used in which a thin layer of toner is formed, and a toner image is formed by applying the thin layer of the toner to or from the photoreceptor with or without contact with the photoreceptor.

At this time, the frequency of the AC bias is 0.5
-10 kHz, AC bias is 0.3-1.2 kV (p
-P), and the peripheral speed ratio between the photoconductor and the developing roller is 1:
By setting 1.2 to 1: 1.8, dots can be faithfully reproduced, good development γ characteristics can be obtained, and a high quality image can be realized. Then, low ground fog and high image density can be obtained. Frequency is 0.5 to 5 kHz, AC bias is 0.3 to 1.
0 kV (p-p), and the peripheral speed ratio between the photoconductor and the developing roller is more preferably 1: 1.2 to 1: 1.5, further preferably 0.5 to 2 kHz and AC bias. It is 0.5 to 0.9 kV (pp), and the peripheral speed ratio between the photoconductor and the developing roller is 1: 1.2 to 1: 1.4.

At this time, if the frequency is lower than 0.5 kHz, dot reproducibility deteriorates and halftone reproducibility deteriorates. When the frequency is higher than 10 kHz, it is impossible to follow the development area, and the effect does not appear. AC bias is 0.
When it is smaller than 3 kV (pp), the solid tracking ability maintaining effect cannot be obtained, and when the AC bias is larger than 1.2 kV (pp), fog increases. When the peripheral speed ratio between the photoconductor and the developing roller is smaller than 1: 1.2 (the developing roller becomes slow), it is difficult to obtain the image density. When the peripheral speed ratio between the photoconductor and the developing roller becomes larger than 1: 1.8 (the developing roller speed increases), the toner scattering increases.

The supply roller and the developing roller are rotated in the same direction, and the peripheral speeds of the developing roller and the supplying roller are 1: 1 to 0.8:
The developing roller speed is increased at a rate of 0.2. The developing roller is 9.8 to 9.8 × 10 on the surface of the photoconductor.
The electrostatic latent image on the photoconductor is developed by pressing with a pressure of ² (N). The elastic blade is pressed against the developing roller with a pressure of 5 to 5 × 10 ² (N) to form a toner layer.

Further, in order to control the toner supply amount on the developing roller when the toner supply amount supplied from the toner reservoir is conveyed to the developing roller, a sponge-like supply roller made of urethane resin or the like is used. The contact is made with the developing roller with a constant biting amount of 0.1 to 1 mm with respect to the developing roller.

In order to control the toner supply amount on the developing roller when the toner supply amount supplied from the toner reservoir is conveyed to the developing roller, a sponge-like supply roller made of urethane resin or the like is used as the developing roller. The structure provided in contact with is taken. This is an effective means for regulating the toner conveyance amount to a fixed amount.

However, with the conventional toner, in this developing structure, when it is used for a long period of time, scratches on the developing roller and image defects such as vertical stripes on the image due to foreign matter adhering to the blade are likely to occur. In particular, in order to improve the color fixing property, the use of a binder resin having a low softening property and the toner containing a low melting point release agent occur more remarkably.

Further, the toner conveyance amount on the developing roller decreases during long-term continuous use, and when a solid black image is taken, the density of the latter half of the image partially decreases, and a solid followability defect is likely to occur. . When the charge amount of the toner on the developing roller was measured by a suction method, it was found that the charge amount was significantly reduced. Pursuing further, the charge amount of the toner on the supply roller unit has greatly increased, that is, the decrease in the image density does not mean that the charge amount of the toner has decreased, but the supply roller unit before it is supplied to the developing roller unit. This is because the charging capacity has been increased and the supply capacity from the supply roller to the developing roller has decreased. Therefore, it is necessary to have a configuration capable of ensuring the image density while preventing the toner from scattering. It is also effective to increase the contact pressure of the doctor blade to increase the charging ability of the toner, but the toner is likely to be fused and the developing roller is damaged.

Therefore, it has been found that, by adopting the toner constitution of this embodiment, it is possible to prevent the generation of vertical stripes on the developing roller, the poor solid-following property, and the toner fusion without sacrificing the fixing characteristics. It was

This enables uniform dispersion in the resin,
The charge distribution is stabilized, overcharge of the toner on the supply roller is suppressed, the fluidity is stabilized, and the followability of a solid image is improved. Due to the uniform dispersion, the fluidity of the toner can be maintained, the toner can be smoothly conveyed on the developing roller, and the conveying state can be always stabilized. In particular, it is very effective in stabilizing the transportation state under high humidity. At this time, it is preferable that the toner charge amount on the developing roller by the suction type Faraday cage method is | 5 | to | 45 | μC / g. If it is smaller than | 5 | μC / g, toner scattering increases. If it is larger than | 45 | μC / g, it is difficult to obtain the image density.

To measure the charge amount of toner by the suction type Faraday cage method, the toner on the developing roller is sucked while rotating, and the sucked toner is collected by a filter,
Obtain its weight W (g). Further, the voltage V (V) induced in the capacitor is measured as the charge amount when the charged toner moves during suction, and Q (μC / g) = C (F) × V
The charge amount is calculated from (V) / W (g).

Further, in this embodiment, there is no cleaning process step of collecting the toner remaining on the photoconductor after the transfer process by cleaning, and the following charging, exposure, and
It is suitable for use in an electrophotographic apparatus having a cleanerless process as a basic structure for performing a developing process.

By using the toner of the present embodiment, aggregation of the toner can be suppressed, overcharge can be prevented, and chargeability can be stabilized.
It is possible to obtain high transfer efficiency. Further, due to the improved uniform dispersibility in the resin, the good charging property, and the releasing property of the material, the toner remaining in the non-image area can be favorably collected by the development. Therefore, the development memory in which the image pattern before the non-image portion remains is not generated.

Further, the present embodiment is preferably used in an electrophotographic apparatus having a fixing process in which a belt type fixing medium is used as a means for fixing toner. As the belt, a nickel electroformed belt or a polyimide belt having heat resistance and deformability is used. In order to improve the releasability, silicone rubber, fluororubber, or fluororesin is used as the surface layer. Release oils have been applied to these fixing belts to prevent offset. A toner having releasability without using oil eliminates the need to apply release oil. However, if the release oil is not applied, the toner tends to be charged, and if the unfixed toner image approaches the belt, the toner may fly due to the influence of the charging. Especially, it tends to occur at low temperature and low humidity. In addition, when the toner has a certain amount of high molecular weight component added to prevent high-temperature offset and has a certain amount of elastic element, the paper with the fine vertical line pattern of the toner is drawn at the tip of the paper when it is separated from the belt with a large curvature. May cause a tip offset that may be brought to the belt. In addition, compared to the conventional rigid fixing roller, the elastic belt type has a problem of shortening the life due to scratches due to no oil.

Therefore, by using the toner of the present embodiment, it is possible to prevent the occurrence of offset without using oil and to obtain high color translucency. Further, the overcharge property of the toner can be suppressed, and the toner fly due to the charging action with the belt can be suppressed. Further, it is possible to prevent the offset toner from being separated from the belt by the effect of the molecular weight distribution and slipperiness of the offset toner which is brought to the belt.

Next, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to this.

The characteristics of the binder resin used in the examples are shown in (Table 1). As the resin, a polyester resin containing bisphenol A propyl oxide adduct, terephthalic acid, trimellitic acid, succinic acid, and fumaric acid as main components was used, and a resin having different thermal characteristics depending on the compounding ratio and the polymerization conditions was used.

[0178]

[Table 1]

Mnf is the number average molecular weight of the binder resin, Mwf
Is the weight average molecular weight of the binder resin, Mzf is the Z average molecular weight of the binder resin, Wmf is the ratio Mwf / Mnf of the weight average molecular weight Mwf to the number average molecular weight Mnf, and Wzf is the Z of the binder resin.
Ratio of average molecular weight Mzf and number average molecular weight Mnf Mzf / M
nf and AV represent resin acid values.

Tables 2 and 3 show the waxes used in this example and the physical properties thereof. Mnr is the number average molecular weight of the wax, Mwr is the weight average molecular weight of the wax, Mzr
Indicates the Z-average molecular weight of the wax. Tw (° C) is DSC
The melting point by the method, Ct (%) shows the volume increase rate (%) at the melting point + 10 ° C., and Ck (wt%) shows the heating loss of 220 ° C.

[0181]

[Table 2]

[0182]

[Table 3]

Table 4 shows the pigments used in this example.

[0184]

[Table 4]

Table 5 shows the charge control agents used in this example.

Examples of the metal salt of a salicylic acid derivative include an alkyl group having 1 to 10 carbon atoms such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a tert group. A butyl group and the like. As the metal Y, zinc, nickel,
Examples thereof include cobalt, copper and chromium, with zinc and chromium being preferred. Examples of the metal salt of the benzylic acid derivative include benzene rings for R ^{1 to} R ⁴ , and examples of the alkali metal X include lithium, sodium and potassium, with potassium being preferred.

[0187]

[Table 5]

Table 6 shows the external additives used in this example. The charge amount is measured by a blow-off method of frictional charging with a non-coated ferrite carrier. Two
50 g of carrier and 0.1 g of silica are mixed in a 100 ml polyethylene container in an environment of 5 ° C. and 45% RH, and the mixture is stirred longitudinally at a speed of 100 min ⁻¹ for 5 minutes and 30 minutes, and then 0.3 g is collected. Nitrogen gas 1.96 × 10 ⁴ (P
It was blown for 60 seconds in a).

In the case of positive charging, the value at 5 minutes after stirring for 5 minutes is +1.
The value at 30 minutes after stirring for 30 minutes at +00 to +800 μC / g is preferably +50 to +400 μC / g.
Silica in which the charge amount at the 30-minute value maintains 40% or more of the charge amount at the 5-minute value is preferable. If the rate of decrease is large, the amount of charge changes greatly during long-term continuous use, and it becomes impossible to maintain a constant image.

In the negative charging property, the value at 5 minutes is -100 to -800.
A value of 30 minutes in μC / g is preferably −50 to −600 μC / g. Highly charged silica can exhibit its function with a small amount of addition.

[0191]

[Table 6]

As a kneading condition in this example, a roll (R
The heating temperature of the first half of L1) is 130 ° C. and the roll (RL
The heating temperature of the latter half of 1) is 60 ° C, the heating temperature of the roll (RL2) is 20 ° C, and the rotation speed of the roll (RL1) is 75 m.
in ^-1 , roll (RL2) rotation speed 50 min ^-1 , raw material input amount 15 kg / h, roll (RL1) (RL2)
The diameter was 140 mm and the length was 800 mm.

Table 7 shows the toner material composition used in this example.

[0194]

[Table 7]

The weight average particle diameter of each toner is 6 to 7
μm, the variation coefficient of the volume particle size distribution is 20 to 25%, and the variation coefficient of the number particle size distribution is 25 to 30%.

Regarding the compounding ratio of the pigment, charge control agent and wax, the compounding ratio (parts by weight) to 100 parts by weight of the binder resin is shown in parentheses. The external additive indicates the blending amount (parts by weight) with respect to 100 parts by weight of the toner base. External addition processing is FM20B
, Stirring blade Z0S0 type, rotation speed 2000 rp
m, the treatment time was 5 min, and the charged amount was 1 kg.

(Table 8) and (Table 9) show the molecular weight characteristics of the toner after the kneading treatment in this example. The toner was comparatively evaluated with magenta toner TM1 to 3 toner. Similar results are obtained with yellow, cyan and black toners. M
nv is the number average molecular weight of the toner, Mwv is the weight average molecular weight of the toner, Wmv is the ratio Mwv / Mnv of the weight average molecular weight Mwv of the toner and the number average molecular weight Mnv, and Wzv is the ratio of the Z average molecular weight Mzv of the toner and the number average molecular weight Mnv. Mzv
/ Mnv is shown.

ML is the molecular weight value showing the maximum molecular weight peak on the low molecular weight side in the molecular weight distribution, MH is the molecular weight value showing the maximum molecular weight peak on the high molecular weight side, and Sm is Hb / Ha, S.
K1 is M10 / M90, SK2 is (M10-M90) /
M90 is shown.

[0199]

[Table 8]

[0200]

[Table 9]

The molecular weight distribution characteristics are shown in FIGS.

FIGS. 5a and 5b respectively show the binder resin PES.
-1, toner TM-1 molecular weight distribution characteristics, FIG. 6a, FIG.
b is the binder resin PES-2, the molecular weight distribution characteristics of the toner TM-2, and FIGS. 7a and 7b are the binder resin PE.
The molecular weight distribution characteristics of S-3 and Toner TM-3 are shown.

The binder resin PES-1 has a high molecular weight component of 3 × 10 ⁴ or more in an area ratio of 5% or more with respect to the entire molecular weight distribution of the binder resin. Further, 3 × 10 ^{5 to} 9 × 10 ⁶ high molecular weight components are used in an area ratio of 1 to the entire binder resin molecular weight distribution.
% Or more. Similarly, PES-2, 3, 4 is also 3 × 1
A high molecular weight component of 0 ⁴ or more is present in an area ratio of 5% or more with respect to the entire binder resin molecular weight distribution. Also 3 × 10 ^{5 to} 9
It has a high molecular weight component of × 10 ^{6 in} an area ratio of 1% or more with respect to the entire binder resin molecular weight distribution.

It can be seen that the toner is molecularly cleaved by kneading and appears as a peak or a shoulder on the side of the polymer component. That is, the component that inhibits the light-transmitting property disappears due to the cutting and appears as a steep slope on the polymer side, which is a factor that maintains the offset resistance without hindering the light-transmitting property. 3x1 for Toner TM-1
The amount of the high molecular weight component of 0 ⁵ or more is 5% or less in the area ratio with respect to the entire toner molecular weight distribution, and the high molecular weight component of 1 × 10 ⁶ or more is hardly contained. Similarly, TM-2, 3,
In No. 4 as well, the amount of the high molecular weight component of 3 × 10 ⁵ or more is 5% or less in terms of the area ratio to the entire toner molecular weight distribution, and the high molecular weight component of 1 × 10 ⁶ or more is hardly contained.

8 and 9 show examples of molecular weight distribution characteristics. FIG. 9 schematically shows M10 and M90, which have a characteristic of having a sharp molecular weight peak on the polymer component side. The maximum peak height of the molecular weight distribution is 100%. Figure 10
Shows schematically M10 and M90 of the molecular weight distribution characteristics of Toner TM-3. It appears as a shoulder shape on the side of the polymer component, and the height of the apex of the shoulder of this shoulder portion is used as a reference of 100%. This is the binder resin PES3
This is because the high molecular weight component of (1) was molecularly cut by kneading and appeared as a shoulder on the side of the high molecular component.

The peak height of the distribution on the polymer side is 100
%, The molecular weight curve in a region larger than the molecular weight value corresponding to the maximum peak or shoulder, that is, the region where the slope of the molecular weight distribution curve in this region is negative,
That is, in the right part of the distribution curve, when the height of the peak or shoulder of the molecular weight distribution is 100%, the molecular weight corresponding to 90% of the peak or shoulder of the molecular weight is M90, and the peak or shoulder of the molecular weight is 90%. The molecular weight corresponding to 10% of the height of M is defined as M10. Here, the value of M10 / M90 (the slope of the molecular weight distribution curve) can quantify the molecular cleavage state of the ultrahigh molecular weight component. The small value of M10 / M90 means that the slope of the molecular weight distribution curve is steep, and the component obstructing the light-transmitting property disappears due to the cutting, resulting in high light-transmitting property. Furthermore, the peak appearing on the polymer side contributes to the offset resistance.

FIG. 10 shows the molecular weight distribution characteristics of the fixing aid WB-1. The horizontal axis is the logarithm of the molecular weight.

(Embodiment 1) FIG. 11 is a sectional view showing the arrangement of an electrophotographic apparatus for forming a full-color image used in this embodiment. In FIG. 13, the outer casing of the color electrophotographic printer is omitted. The operation of attaching / detaching the transfer belt unit 2 in the printer and inspecting / maintenance of the inside of the printer at the time of paper jam, etc. are performed by tilting the front plate open to largely open the inside of the printer. The transfer belt unit 17 is designed to be attached / detached in a direction parallel to the rotation axis generatrix direction of the photoconductor.

The transfer belt unit 17 is the transfer belt 1
2. First color (yellow) transfer roller 10 made of an elastic body
Y, second color (magenta) transfer roller 10M, third color (cyan) transfer roller 10C, fourth color (black) transfer roller 10K, drive roller 11 made of an aluminum roller, second transfer roller 14 made of an elastic body, Second transfer driven roller 1
3, a belt cleaner blade 16 for cleaning the toner image remaining on the transfer belt 12, and a roller 15 at a position facing the cleaner blade.

At this time, from the first color (Y) transfer position to the second
The distance to the color (M) transfer position is 42 mm (second color (M)
The transfer position is the third color (C) transfer position, the third color (C) transfer position is the same as the fourth color (K) transfer position), and the peripheral speed of the photoconductor is 100 mm / s.

The transfer belt 12 is used by kneading a conductive filler in an insulating polycarbonate resin and forming a film with an extruder. In this example, as an insulating resin, a film obtained by adding 5 parts by weight of conductive carbon (eg, Ketjen black) to 95 parts by weight of a polycarbonate resin (for example, Iupilon Z300 manufactured by Mitsubishi Gas Chemical Co., Inc.) was used. Also, the surface is coated with fluororesin,
Thickness is about 120 μm and volume resistance is 10 ⁷ to 10 ¹² Ω · c.
m, and the surface resistance is 10 ⁷ to 10 ¹² Ω / □. It is also for improving dot reproducibility. The transfer belt 12 is for effectively preventing loosening and charge accumulation due to long-term use, and the surface of the transfer belt 12 is coated with a fluororesin. This is to enable effective prevention. When the volume resistance is less than 10 ⁷ Ω · cm, retransfer easily occurs, and when it is more than 10 ¹² Ω · cm, the transfer efficiency is deteriorated.

The first transfer roller is a carbon conductive urethane foam roller having a diameter of 14 mm and has a resistance value of 10 ² to 10 ⁶ Ω.
Is. During the first transfer operation, the first transfer roller 10
1.0 to 9.8 on the photoconductor 1 via the transfer belt 12.
The toner on the photoconductor is transferred onto the belt by being pressed by the pressing force of (N). When the resistance value is smaller than 10 ² Ω, retransfer is likely to occur. Larger than 10 ⁶ Ω, transfer defects are more likely to occur. If it is less than 1.0 (N), transfer failure will occur, and if it is greater than 9.8 (N), transfer character omission will occur.

The second transfer roller 14 is a carbon conductive urethane foam roller having a diameter of 20 mm and has a resistance value of 10 ² to 1 1.
It is 0 ⁶ Ω. The second transfer roller 14 is the transfer belt 12
And the transfer roller 13 via a transfer medium such as paper or OHP.
Is pressed against. The transfer roller 13 is configured to be rotatable following the transfer belt 12. The second transfer roller 14 and the counter transfer roller 13 in the second transfer have 5.0 to 21.8.
The toner is transferred from the transfer belt onto the recording material such as paper by being pressed by the pressing force of (N). When the resistance value is smaller than 10 ² Ω, retransfer is likely to occur. Larger than 10 ⁶ Ω, transfer defects are more likely to occur. If it is less than 5.0 (N), transfer failure will occur, and if it is more than 21.8 (N), the load will be large and jitter will easily occur.

In FIG. 11, four sets of image forming units 18Y, 18M, 18C and 18K for yellow (Y), magenta (M), cyan (C) and black (B) are connected in series as shown in the figure. Are arranged in a shape.

Image forming units 18Y, 18M, 18
C and 18K are composed of the same constituents except for the developer contained therein, so the image forming unit 18Y for Y will be described and the description for the units for other colors will be omitted for the sake of simplicity.

The image forming unit is constructed as follows. 1 is a photoconductor, 3 is pixel laser signal light, 4 is JIS
A φ18 mm developing roller made of silicone rubber having a hardness of −A is pressed against the photoconductor with a force of 21 N and rotated in the direction of the arrow. A supply roller 6 made of a conductive urethane sponge having a diameter of 14 mm supplies the toner in the toner hopper to the developing roller. A metal blade 5 forms a toner layer on the developing roller. Although the power supply is omitted, the developing roller 4 has a direct current of -230V and a voltage of 500V.
(Pp), an alternating voltage with a frequency of 1 kHz is applied.
A DC bias of −330 V is applied to the supply roller 6.

2 is φ1 made of epichlorohydrin rubber
A DC bias of −1 kV is applied with a 2 mm charging roller. The surface of the photoreceptor 1 is charged to -450V. Reference numeral 8 is a cleaner, 9 is a waste toner box, and 7 is toner.

The paper is carried from below the transfer unit 17, and the paper is fed by a paper feeding roller (not shown) to the nip portion where the transfer belt 12 and the second transfer roller 14 are in pressure contact with each other. , A paper transport path is formed.

The toner on the transfer belt 12 is transferred to the paper by + 1300V applied to the second transfer roller 14,
Fixing roller 201, pressure roller 202, fixing belt 20
3, heating medium roller 204, induction heater unit 2
The sheet is conveyed to a fixing unit composed of 05 and is fixed there.

FIG. 12 shows the fixing process diagram. The belt 20 is provided between the fixing roller 201 and the heat roller 204.
It is multiplied by 3. Fixing roller 201 and pressure roller 2
A predetermined weight is applied to the belt 20 and the belt 20.
A nip is formed between the pressure roller 202 and the pressure roller 202. The ferrite core 20 is provided on the outer peripheral surface of the heat roller 204.
6, an induction heater unit 2 including a coil 207
05 is provided, and a temperature sensor 208 is arranged on the outer surface.

The belt is made of Ni of 30 μm as a base material, silicone rubber of 150 μm on it, and PF on it.
It has a structure in which A tubes of 30 μm are superposed.

The pressure roller 202 is pressed against the fixing roller 201 by the pressure spring 209. Toner 210
The recording material 211 having a mark moves along the guide plate 212.

The fixing roller 201 as a fixing member has a length of 250 mm, an outer diameter of 14 mm, and a thickness of 1 mm, which is a hollow roller core metal 213 made of aluminum and has a rubber hardness (JIS-A) of 20 degrees according to JIS standard. An elastic layer 214 made of silicone rubber having a thickness of 3 mm is provided. A silicone rubber layer 215 having a thickness of 3 mm is formed thereon to have an outer diameter of about 20 mm. It receives a driving force from a driving motor (not shown) and rotates at 100 mm / s.

The heat roller 204 has a wall thickness of 1 mm and an outer diameter of 2
It consists of a 0 mm hollow pipe. The surface temperature of the fixing roller was controlled to 170 ° C. using a thermistor.

The pressure roller 202 as a pressure member has a length of 250 mm and an outer diameter of 20 mm. This is outer diameter 16
mm, 1 mm thick aluminum hollow roller core metal 216 has a rubber hardness (JIS-
An elastic layer 217 having a thickness of 2 mm and made of silicone rubber having A of 55 degrees is provided. The pressure roller 202 is rotatably installed, and has a width of 5.0 m between the pressure roller 202 and the fixing roller 201 by a spring-loaded spring 209 on one side 147N.
forming a nip width of m.

The operation will be described below. In full-color mode, all Y, M, C, K first transfer rollers 1
0 is pushed up and presses the photoconductor 1 of the image forming unit via the transfer belt 12. At this time, a direct current bias of +800 V is applied to the first transfer roller. An image signal is sent from the laser beam 3 and is incident on the photoconductor 1 whose surface is charged by the charging roller 2 to form an electrostatic latent image. The toner 7 on the developing roller 4 which is in contact with the photoconductor 1 and rotates in the opposite direction visualizes the electrostatic latent image formed on the photoconductor 1.

At this time, the image forming speed of the image forming unit 18Y (100 mm / s which is equal to the peripheral speed of the photoconductor) and the moving speed of the transfer belt 12 are such that the photoconductor speed is 0.5 to 1.5 higher than the transfer belt speed. % It is set to be slow.

In the image forming step, the Y signal light 3Y is input to the image forming unit 18Y, and the image is formed by the Y toner. Simultaneously with image formation, the Y toner image is transferred from the photoconductor 1Y to the transfer belt 12 by the action of the first transfer roller 10Y. At this time, + 800V is applied to the first transfer roller 10Y.
DC voltage was applied.

With a time lag between the first transfer of the first color (Y) and the first transfer of the second color (M), the M signal light 3M is input to the image forming unit 18M, and the image formation by the M toner is performed. At the same time as the image formation, the M toner image is transferred from the photoconductor 1M to the transfer belt 12 by the action of the first transfer roller 10M. At this time, the M toner is transferred on the first color (Y) toner. Similarly, C (cyan), K
An image is formed by the (black) toner, and at the same time when the image is formed, YMCK is performed by the action of the first transfer rollers 10C and 10B.
A toner image is formed on the transfer belt 12. This is a so-called tandem system.

On the transfer belt 12, toner images of four colors were positionally aligned and overlaid to form a color image. After the final transfer of the B toner image, the four color toner images are collectively transferred by the action of the second transfer roller 14 onto the paper fed from the paper feed cassette (not shown) at the same timing. At this time, the transfer roller 13 was grounded, and a DC voltage of +1.3 kV was applied to the second transfer roller 14. The toner image transferred on the paper was fixed by the pair of fixing rollers 201 and 202. The paper was then ejected out of the apparatus via a pair of ejection rollers (not shown). The transfer residual toner remaining on the intermediate transfer belt 12 is cleaned by the action of the cleaning blade 16 to prepare for the next image formation.

FIG. 13 shows a tandem system in which the paper 18 is carried on the paper carrying belt 17 and the toner on the OPC is directly transferred without performing the primary transfer to the belt.

Table 10 shows the results of image output by the electrophotographic apparatus of FIG. In (Table 11), the state of transfer failure in the character portion in the full-color image in which the toners are overlapped by three colors and the winding property of the paper on the fixing belt during fixing are evaluated.

[0233]

[Table 10]

[0234]

[Table 11]

An image was printed by the electrophotographic apparatus shown in FIG. 11 using the toner manufactured as described above. As a result, horizontal black lines were not disturbed, the toner was not scattered, and the solid black image was uniform. , An image of extremely high resolution and high quality in which even 16 lines / mm of image lines were reproduced, and a high-density image with an image density of 1.3 or more was obtained. Further, the background fog in the non-image area did not occur. Further, even in the long-term durability test of 10,000 A4 sheets, the fluidity and the image density showed little change and showed stable characteristics. Further, the uniformity when a solid image was taken on the entire surface during development was also good. There is no development memory. Also, in the transfer, the void was at a level where there was no practical problem, and the transfer efficiency was 90%. Further, the filming of the toner on the photoconductor and the transfer belt was at a level where there was no practical problem. The cleaning failure of the transfer belt did not occur either. In addition, the toner is not disturbed and the toner does not fly during fixing. Also, in the cleaner process in which the residual toner at the time of transfer is collected in the development as it is without using the cleaning blade 8,
Collection was done smoothly, and the history of the previous image did not remain. In addition, even in a full-color image with three overlapping colors,
No transfer failure occurred, and paper did not wrap around the fixing belt during fixing. Similar results were obtained by the electrophotographic apparatus shown in FIG.

However, the toners tm7, ty7, tc7, and tb7 caused filming of the photosensitive member, transfer failure, scattering of characters at the time of transfer, and much fog. Filming of the transfer belt and poor cleaning occurred. When a solid image was taken on the entire surface at the time of development, blurring occurred in the latter half. Wrapping of paper around the fixing belt occurred when outputting images of three colors. Toner skipping occurred during fixing.

Next, as shown in (Table 12), the adhered amount of 1.
Process speed of 100 mm for solid images of ² g / cm ² or more
/ S, a non-offset property test was conducted with a fixing device using a belt to which no oil was applied. No OHP jam occurred in the fixing nip portion. In the whole solid green image on plain paper, offset did not occur up to the 122,000th sheet. Even if the silicone or fluorine fixing belt is not coated with oil, the surface deterioration phenomenon of the belt is not observed.

The transmittance and the offset property at high temperature were evaluated. Process speed is 100mm / s, fixing temperature is 180 ℃
And the transmittance is spectrophotometer U-3200 (Hitachi),
The transmittance of 700 nm light was measured. The results of fixability, offset resistance, and storage stability are shown.

[0239]

[Table 12]

OHP transparency is 80% or more,
Further, the non-offset temperature width was 40 to 60 K, which showed good fixing properties in a fixing roller not using oil. Further, almost no aggregation was observed in the storage stability at 60 ° C. for 5 hours.

However, the toner of tm7 had a lump in the storage stability test, and the non-offset temperature range was narrow.

[0242]

As described above, according to the present invention, the particle size is 2
It contains 5 to 50% by number of particles of × 10 ^{-6 to} 5 × 10 ^-6 m and has a compression degree of 5 to 4 calculated from the static bulk density and the dynamic bulk density.
Due to the composition that uses 0% toner, the distance from the first primary transfer position to the second primary transfer position is short and the transferability in the high-speed tandem transfer process is realized, and further the oilless fixing is realized. it can.

Further, a fixing aid containing a wax having an iodine value of 25 or less and a saponification value of 30 to 300 is added,
By using 1 to 12 parts by weight of the toner added to 100 parts by weight of the binder resin having an acid value of 1 to 70 mgKOH / g, it is possible to prevent hollow defects and scattering at the time of transfer and obtain high transfer efficiency. It will be possible. Filming of the photoconductor and the transfer body can be prevented even during long-term use under high humidity. The cleaning property of the transfer member can be improved. Even in the cleaning process that does not use the cleaning blade, the transfer residual toner can be smoothly collected, and the history of the previous image can be prevented from remaining.

The offset property can be prevented while maintaining high OHP translucency without applying oil with a silicone or fluorine-based fixing means (roller or belt). Further, even if the belt is used for a long period of time, a good non-offset property can be maintained without causing a surface deterioration phenomenon of the belt.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of a toner melt-kneading process used in an example of the present invention.

FIG. 2 is a plan view of a toner melt-kneading process used in an example of the present invention.

FIG. 3 is a front view of a toner melt-kneading process used in an example of the present invention.

FIG. 4 is a sectional view of a toner melt-kneading process used in an example of the present invention.

FIG. 5 is a diagram showing molecular weight distribution characteristics of a binder resin and a toner according to an example of the present invention.

FIG. 6 is a diagram showing molecular weight distribution characteristics of a binder resin and a toner according to an example of the present invention.

FIG. 7 is a diagram showing molecular weight distribution characteristics of a binder resin and a toner according to an example of the present invention.

FIG. 8 is a diagram showing the molecular weight distribution characteristics of the fixing aid of the example of the present invention.

FIG. 9 is a diagram showing the molecular weight distribution characteristics of the toner of the example of the present invention.

FIG. 10 is a diagram showing the molecular weight distribution characteristics of the toner of the example of the invention.

FIG. 11 is a sectional view showing the structure of an electrophotographic apparatus used in an example of the present invention.

FIG. 12 is a cross-sectional view showing the configuration of a fixing unit used in an example of the present invention.

FIG. 13 is a sectional view showing the structure of an electrophotographic apparatus used in an example of the present invention.

[Explanation of symbols]

1 photoconductor 3 laser signal light 4 developing roller 5 blade 10 first transfer roller 12 transfer belt 14 second transfer roller 13 drive tension roller 17 transfer belt units 18B, 18C, 18M, 18Y image forming unit 18 image forming unit group 201 fixing Roller 202 Pressure roller 203 Fixing belt 205 Induction heater section 206 Ferrite core 207 Coil 602 Roll (RL1) 603 Roll (RL2) 604 Melted film of toner wound on roll (RL1) 605 Heat medium inlet 606 Heat medium Outlet of

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G03G 15/01 G03G 15/01 114A 114 15/16 103 15/16 103 9/08 321 331 F term (reference) ) 2H005 AA01 AA06 CA08 CA14 EA03 EA05 EA06 EA07 EA10 2H030 AA06 AB02 AD01 BB02 BB21 BB42 BB46 2H071 DA09 EA04 EA18 2H200 FA16 GA12 GA23 GA34 GA44 GA47 GB12 GB25 GB41 HA02 HB12 JA02 JB10 J14 LA12 J14

Claims (18)

[Claims] 1. A plurality of toner image forming stations including at least an image bearing member, a charging unit for forming an electrostatic latent image on the image bearing member, and a toner bearing member, and the electrostatic image formed on the image bearing member. A primary transfer process in which a toner image in which a latent image is visualized is transferred to the transfer member by bringing an endless transfer member into contact with the image carrier is continuously executed at four primary transfer positions, A transfer system configured to perform a secondary transfer process of forming a multi-layered transfer toner image on the transfer body and then collectively transferring the multi-layered toner image formed on the transfer body to a transfer medium, The transfer process includes a distance from the first primary transfer position to the second primary transfer position, or a distance from the second primary transfer position to the third primary transfer position, or a third primary transfer position to the fourth primary transfer position. Up to the primary transfer position A release d1 (mm), if the peripheral speed of the photosensitive member was as v (mm / s), d1 / v ≦
The toner has a constitution satisfying the condition of 0.65 (sec), and the toner contains 5 to 50% by number of particles having a particle size of 2 × 10 ^{−6 to} 5 × 10 ⁻⁶ m, and has a static bulk density and a dynamic volume. A toner having a compression degree of 5 to 40% calculated from the bulk density. 2. A plurality of toner image forming stations including at least an image carrier, a charging unit for forming an electrostatic latent image on the image carrier, and a toner carrier, and the electrostatic image formed on the image carrier. A transfer system configured to perform a transfer process of sequentially transferring the toner image in which the latent image is visualized to the transfer medium at four primary transfer positions is provided. The distance from the transfer position to the second transfer position, the distance from the second transfer position to the third transfer position, or the distance from the third transfer position to the fourth transfer position is d1 (mm). The peripheral speed of the body is v (mm /
s), the constitution is such that the condition of d1 / v ≦ 0.65 (sec) is satisfied, and the toner has a particle size of 2 × 1.
A toner containing 5 to 50% by number of particles of 0 ^{−6 to} 5 × 10 ⁻⁶ m and having a compression degree of 5 to 40% calculated from a static bulk density and a dynamic bulk density. 3. An image carrier and at least the image carrier
Toner including charging means for forming an electrostatic latent image and a toner carrier
Having multiple image forming stations, Toner that visualizes the electrostatic latent image formed on the image carrier
The image is transferred to the image carrier with an endless transfer member in contact with the image.
The primary transfer process of transferring to the transfer body is performed by four primary transfer processes.
Repeatedly and continuously in the shooting position, and
Layer transfer toner image is formed and then formed on the transfer body
The secondary transfer that collectively transfers the multi-layered toner image to the transfer medium.
A transfer system configured to carry out the copying process.
Be equipped with And the transfer process is performed from the first primary transfer position to the second primary transfer position.
Distance to the primary transfer position or the second primary transfer position
To the third primary transfer position, or the third primary transfer
The distance from the position to the fourth primary transfer position is d1 (m
m), when the peripheral speed of the photoconductor is v (mm / s), d
The configuration satisfies the condition of 1 / v ≦ 0.65 (sec).
The electrostatic latent image formed on the image carrier has a particle size of 2 × 10
^-6~ 5 x 10 ^-65-50% by number of m particles,
The degree of compression calculated from the density and the dynamic bulk density is 5 to 40%
Electrophotography characterized by making visible image with toner
apparatus. 4. A plurality of toner image forming stations including at least an image bearing member, a charging unit for forming an electrostatic latent image on the image bearing member, and a toner bearing member, and the electrostatic image formed on the image bearing member. A transfer system configured to execute a transfer process of sequentially transferring a toner image, which is a latent image visualized, to a transfer medium at four primary transfer positions, and the transfer process includes a first transfer process. From the transfer position to the second transfer position, the distance from the second transfer position to the third transfer position, or the distance from the third transfer position to the fourth transfer position is d1 (mm), The peripheral speed of the photoconductor is v (m
m / s), the structure satisfies the condition of d1 / v ≦ 0.65 (sec), and the electrostatic latent image formed on the image carrier has a particle size of 2 × 10 ^{−6 to} 5 5 × 10 ⁻⁶ m particles
An electrophotographic apparatus comprising a toner containing 50% by number and having a compression degree of 5 to 40% calculated from a static bulk density and a dynamic bulk density to form a visible image. 5. An electrostatic latent image forming unit having a plurality of toner image forming stations including at least an image carrier, a charging unit for forming an electrostatic latent image on the image carrier, and a toner carrier. A primary transfer process in which a toner image in which a latent image is visualized is transferred to the transfer body by bringing an endless transfer body into contact with the image carrier is successively executed at four primary transfer positions. A transfer system configured to perform a secondary transfer process of forming a multi-layered transfer toner image on the transfer body and then collectively transferring the multi-layered toner image formed on the transfer body to a transfer medium; A fixing process for fixing the toner transferred to the medium by a fixing member that does not use release oil, wherein the transfer process is a distance from a first primary transfer position to a second primary transfer position, or a second The distance from the primary transfer position to the third primary transfer position or the distance from the third primary transfer position to the fourth primary transfer position is d1 (mm), and the peripheral speed of the photoconductor is v (mm / s). , D1 / v ≦
The toner satisfies the condition of 0.65 (sec), and the toner has a number average molecular weight of 100 to 5 in the molecular weight distribution in gel permeation chromatography (GPC).
000, the weight average molecular weight is 200 to 10,000, the ratio of the weight average molecular weight to the number average molecular weight (weight average molecular weight / number average molecular weight) is 1.01 to 8, the ratio of the Z average molecular weight to the number average molecular weight (Z average molecular weight / number Average molecular weight) is 1.02-1
0, a fixing auxiliary agent containing a wax having at least one maximum molecular weight peak in the region of 5 × 10 ² to 1 × 10 ⁴ and having an iodine value of 25 or less and a saponification value of 30 to 300, an acid value Binder resin 1 of 1 to 70 mgKOH / g
1 to 12 parts by weight to 00 parts by weight, and a particle size of 2
It contains 5 to 50% by number of particles of × 10 ^{-6 to} 5 × 10 ^-6 m and has a compression degree of 5 to 4 calculated from the static bulk density and the dynamic bulk density.
Toner characterized by being 0%. 6. An electrostatic latent image forming unit having a plurality of toner image forming stations including at least an image carrier, a charging unit for forming an electrostatic latent image on the image carrier, and a toner carrier. A transfer system configured to perform a transfer process of sequentially transferring the toner image in which the latent image is visualized to the transfer medium at four primary transfer positions is provided. The distance from the transfer position to the second transfer position, the distance from the second transfer position to the third transfer position, or the distance from the third transfer position to the fourth transfer position is d1 (mm). The peripheral speed of the body is v (mm /
s), the toner satisfies the condition of d1 / v ≦ 0.65 (sec), and the toner has a number average molecular weight of 100 to 5,000 and a weight average molecular weight of 100 to 5,000 in the molecular weight distribution in gel permeation chromatography (GPC). The average molecular weight is 200 to 10,000, and the ratio of the weight average molecular weight to the number average molecular weight (weight average molecular weight / number average molecular weight) is 1.01 to
8. Ratio of Z average molecular weight and number average molecular weight (Z average molecular weight /
Number average molecular weight) is 1.02 to 10 and molecular weight is 5 × 10 ² to
It has at least one maximum molecular weight peak in the 1 × 10 ⁴ region, has an iodine value of 25 or less, and a saponification value of 30 to 3
A fixing aid containing a wax of 00 has an acid value of 1 to 70 m.
1 to 100 parts by weight of a binder resin of gKOH / g
12 parts by weight is added, and the particle size is 2 × 10 ^{−6 to} 5 × 10 ⁻⁶ m.
5 to 50% by number of the above particles, and the degree of compression calculated from the static bulk density and the dynamic bulk density is 5 to 40%. 7. A plurality of toner image forming stations including at least an image bearing member, a charging unit for forming an electrostatic latent image on the image bearing member, and a toner bearing member, and the electrostatic image formed on the image bearing member. A primary transfer process in which a toner image in which a latent image is visualized is transferred to the transfer body by bringing an endless transfer body into contact with the image carrier is successively executed at four primary transfer positions. A transfer system configured to perform a secondary transfer process of forming a multi-layered transfer toner image on the transfer body, and then collectively transferring the multi-layered toner image formed on the transfer body to a transfer medium; And a fixing process for fixing the toner transferred to the transfer medium by a fixing member that does not use release oil, wherein the transfer process is a distance from the first primary transfer position to the second primary transfer position, or The distance from the second primary transfer position to the third primary transfer position or the distance from the third primary transfer position to the fourth primary transfer position is d1 (mm), and the peripheral speed of the photoconductor is v (mm / s). ), D1 / v ≦
The electrostatic latent image formed on the image bearing member has a number average molecular weight of 100 to 5,000 and a weight average molecular weight of 100 to 5,000 in a molecular weight distribution in gel permeation chromatography (GPC). Average molecular weight is 200 ~
10000, the ratio of the weight average molecular weight to the number average molecular weight (weight average molecular weight / number average molecular weight) is 1.08, and the ratio of the Z average molecular weight to the number average molecular weight (Z average molecular weight / number average molecular weight) is 1.02. 10, a fixing aid containing a wax having at least one maximum molecular weight peak in the region of molecular weight 5 × 10 ² to 1 × 10 ⁴ and having an iodine value of 25 or less and a saponification value of 30 to 300, an acid value 1-70mgKOH / g
1 to 12 parts by weight is added to 100 parts by weight of the binder resin, and particles having a particle size of 2 × 10 ^{−6 to} 5 × 10 ⁻⁶ m are added in an amount of 5 to 5.
An electrophotographic apparatus comprising a toner containing 50% by number and having a compression degree of 5 to 40% calculated from a static bulk density and a dynamic bulk density to form a visible image. 8. An electrostatic latent image forming unit having a plurality of toner image forming stations including at least an image carrier, a charging unit for forming an electrostatic latent image on the image carrier, and a toner carrier. A transfer system configured to perform a transfer process in which a toner image in which a latent image is visualized is sequentially and sequentially transferred to a transfer medium at four primary transfer positions, and the toner transferred to the transfer medium is separated. A fixing process for fixing with a fixing member that does not use mold oil, wherein the transfer process is performed from a first transfer position to a second transfer position or from a second transfer position to a third transfer position. Or the distance from the third transfer position to the fourth transfer position is d1 (mm), and the peripheral speed of the photoconductor is v (mm /
s), the configuration satisfies the condition of d1 / v ≦ 0.65 (sec), and the electrostatic latent image formed on the image bearing member is analyzed by gel permeation chromatography (GPC) in terms of molecular weight distribution. , Number average molecular weight 100-500
0, the weight average molecular weight is 200 to 10,000, the ratio of the weight average molecular weight to the number average molecular weight (weight average molecular weight / number average molecular weight) is 1.01 to 8, the ratio of the Z average molecular weight to the number average molecular weight (Z average molecular weight / number A wax having an average molecular weight of 1.02 to 10 and at least one molecular weight maximum peak in a molecular weight range of 5 × 10 ² to 1 × 10 ⁴ , an iodine value of 25 or less, and a saponification value of 30 to 300. A fixing aid containing
1 to 12 parts by weight is added to 100 parts by weight of a binder resin having an acid value of 1 to 70 mgKOH / g, and a particle size of 2 × 10 ⁻⁶
It is characterized by containing 5 to 50% by number of particles having a particle size of from 5 to 10 ^-6 m and having a compression degree of 5 to 40% calculated from the static bulk density and the dynamic bulk density to form a visible image. Electrophotographic device. 9. A toner containing at least a binder resin, a colorant, a fixing aid, and an external additive, having a number average molecular weight of 100 to 5,000 and a weight average molecular weight in a molecular weight distribution in gel permeation chromatography (GPC). Is 200 to 10000, the ratio of the weight average molecular weight to the number average molecular weight (weight average molecular weight / number average molecular weight) is 1.01 to 8, and the ratio of the Z average molecular weight to the number average molecular weight (Z average molecular weight / number average molecular weight) is 1 .02-10, molecular weight 5
A fixing aid containing a wax having at least one peak of molecular weight in the region of x10 ² to 1x10 ⁴ , an iodine value of 25 or less, and a saponification value of 30 to 300 was added with an acid value of 1
1 to 12 parts by weight is added to 100 parts by weight of the binder resin of 70 mgKOH / g, and the particle size is 2 × 10 ^{−6 to} 5 ×.
A toner containing 5 to 50% by number of particles of 10 ⁻⁶ m and having a compression degree of 5 to 40% calculated from a static bulk density and a dynamic bulk density. 10. A plurality of toner image forming stations including at least an image bearing member, a charging unit for forming an electrostatic latent image on the image bearing member, and a toner bearing member, and the electrostatic image formed on the image bearing member. A primary transfer process in which a toner image in which a latent image is visualized is transferred to the transfer body by bringing an endless transfer body into contact with the image carrier is successively executed at four primary transfer positions. A transfer system configured to perform a secondary transfer process of forming a multi-layered transfer toner image on the transfer body and then collectively transferring the multi-layered toner image formed on the transfer body to a transfer medium; A fixing process for fixing the toner transferred to the medium by a fixing member that does not use release oil, wherein the transfer process is a distance from the first primary transfer position to the second primary transfer position, or The distance from the second primary transfer position to the third primary transfer position or the distance from the third primary transfer position to the fourth primary transfer position is d1 (mm), and the peripheral speed of the photoconductor is v (mm / s). ), D1 / v ≦
The toner has a configuration satisfying the condition of 0.65 (sec), and the toner has a weight average molecular weight Mw of 10,000 to 300,000, a ratio Mw / Mn of the weight average molecular weight Mw to the number average molecular weight Mn of 3 to 100, The ratio Mz / Mn of the Z-average molecular weight Mz and the number-average molecular weight Mn is 10 to 2000, the 1/2 outflow temperature by the Koka type flow tester is 80 to 150 ° C., and the outflow start temperature is 8.
A polyester resin obtained by polycondensation of a polyhydric carboxylic acid or a lower alkyl ester thereof having a temperature of 0 to 120 ° C. and a polyhydric alcohol, and having a particle size of 2 × 10 ^{−6 to} 5 ×
A toner containing 5 to 50% by number of particles of 10 ⁻⁶ m and having a compression degree of 5 to 40% calculated from a static bulk density and a dynamic bulk density. 11. A plurality of toner image forming stations including at least an image carrier, a charging unit for forming an electrostatic latent image on the image carrier, and a toner carrier are provided, and the electrostatic image formed on the image carrier is formed. A transfer system configured to perform a transfer process of sequentially transferring the toner image in which the latent image is visualized to the transfer medium at four primary transfer positions is provided. The distance from the transfer position to the second transfer position, the distance from the second transfer position to the third transfer position, or the distance from the third transfer position to the fourth transfer position is d1 (mm). The peripheral speed of the body is v (mm /
s), the toner satisfies the condition of d1 / v ≦ 0.65 (sec), and the toner has a weight average molecular weight Mw of 10,000 to 300,000, a weight average molecular weight Mw and a number average molecular weight Mn. Ratio Mw / Mn of 3 to 100, and the ratio Mz / Mn of Z average molecular weight Mz and number average molecular weight Mn is 10 to 200.
0, ½ outflow temperature is 80 ~
The polyester resin obtained by polycondensation of a polyvalent carboxylic acid or a lower alkyl ester thereof having a flow-out start temperature of 80 to 120 ° C. with a polyhydric alcohol and having a particle size of 2 × 10 ^{−6 to} 5 × 10. particles ^-6 m 5 to 5
A toner containing 0% by number and having a compression degree of 5 to 40% calculated from a static bulk density and a dynamic bulk density. 12. A plurality of toner image forming stations including at least an image bearing member, a charging unit for forming an electrostatic latent image on the image bearing member, and a toner bearing member, and the electrostatic image formed on the image bearing member. A primary transfer process in which a toner image in which a latent image is visualized is transferred to the transfer body by bringing an endless transfer body into contact with the image carrier is successively executed at four primary transfer positions. A transfer system configured to perform a secondary transfer process of forming a multi-layered transfer toner image on the transfer body, and then collectively transferring the multi-layered toner image formed on the transfer body to a transfer medium; A fixing process for fixing the toner transferred to the transfer medium by a fixing member that does not use release oil, wherein the transfer process is a distance from the first primary transfer position to the second primary transfer position, or The distance from the second primary transfer position to the third primary transfer position or the distance from the third primary transfer position to the fourth primary transfer position is d1 (mm), and the peripheral speed of the photoconductor is v (mm / s), d1 / v ≦
The weight average molecular weight Mw of the electrostatic latent image formed on the image carrier is 10,000 to 300,000, the weight average molecular weight Mw and the number average molecular weight Mn are 0.65 (sec).
Ratio Mw / Mn of 3 to 100, ratio Mz / Mn of Z average molecular weight Mz and number average molecular weight Mn is 10 to 2000, and 1/2 outflow temperature by the Koka type flow tester is 80 to 150 ° C.
The outflow starting temperature is 80 to 120 ° C., which contains a polyester resin obtained by polycondensation of a polyhydric carboxylic acid or its lower alkyl ester and a polyhydric alcohol, and has a particle size of 2 × 10 ^{−6 to} 5 × 10 ⁻⁶ m. 5 to 50% by number of particles, and the degree of compression calculated from static bulk density and dynamic bulk density is 5 to 4
An electrophotographic device characterized by forming a visible image with 0% toner. 13. An electrostatic latent image forming unit comprising a plurality of toner image forming stations including at least an image carrier, a charging unit for forming an electrostatic latent image on the image carrier, and a toner carrier. A transfer system configured to perform a transfer process in which a toner image in which a latent image is visualized is sequentially and sequentially transferred to a transfer medium at four primary transfer positions, and the toner transferred to the transfer medium is separated. A fixing process for fixing with a fixing member that does not use mold oil, wherein the transfer process is performed from a first transfer position to a second transfer position or from a second transfer position to a third transfer position. Or the distance from the third transfer position to the fourth transfer position is d1 (mm), and the peripheral speed of the photoconductor is v (mm /
s), the structure satisfies the condition of d1 / v ≦ 0.65 (sec), and the electrostatic latent image formed on the image carrier has a weight average molecular weight Mw of 10,000 to 300,000. The ratio Mw / Mn of the weight average molecular weight Mw and the number average molecular weight Mn is 3 to 10
0, ratio of Z average molecular weight Mz and number average molecular weight Mn Mz / M
n is 10 to 2000, 1/2 by Koka type flow tester
Outflow temperature is 80-150 ° C, outflow start temperature is 80-12
It contains a polyester resin obtained by polycondensation of a polyhydric carboxylic acid or a lower alkyl ester thereof at 0 ° C. and a polyhydric alcohol, and has a particle size of 2 × 10 ^{−6 to} 5 × 10 ⁻⁶ m.
An electrophotographic apparatus comprising 5 to 50% by number of the above particles and having a compression degree of 5 to 40% calculated from the static bulk density and the dynamic bulk density to form a visible image. 14. A toner containing at least a binder resin, a colorant, a fixing aid, and an external additive, wherein the binder resin has a weight average molecular weight Mw of 10,000 to 300,000, and a weight average molecular weight Mw and a number average. The ratio Mw / Mn of the molecular weight Mn is 3 to 100, the ratio Mz / Mn of the Z average molecular weight Mz and the number average molecular weight Mn is 10 to 2000, the 1/2 outflow temperature by the Koka type flow tester is 80 to 150 ° C, and the outflow starts. Temperature is 8
A polyester resin obtained by polycondensation of a polyhydric carboxylic acid or a lower alkyl ester thereof having a temperature of 0 to 120 ° C. and a polyhydric alcohol, and having a particle size of 2 × 10 ^{−6 to} 5 ×
A toner containing 5 to 50% by number of particles of 10 ⁻⁶ m and having a compression degree of 5 to 40% calculated from a static bulk density and a dynamic bulk density. 15. The binder resin contains a polyester resin obtained by polycondensation of a polyhydric alcohol and a carboxylic acid component containing an aromatic dicarboxylic acid and a trivalent or higher polyvalent carboxylic acid or a lower alkyl ester thereof. Claim 1
The toner and electrophotographic apparatus according to any one of 0 to 14. 16. The binder resin comprises a polyester resin obtained by polycondensation of a polyhydric alcohol and a carboxylic acid component containing an aliphatic dicarboxylic acid and a trivalent or higher polycarboxylic acid or a lower alkyl ester thereof. Claim 1
The toner and electrophotographic apparatus according to any one of 0 to 14. 17. The transfer member is a transfer belt, and the transfer belt has a surface resistance of 10 ⁷ to 10 ¹² Ω / □ and a volume resistance of 10 ⁷ to 10 ¹² Ω · cm. ~
13. The toner and electrophotographic apparatus according to any one of 13 above. 18. The resistance value of the transfer roller for the first transfer is 10
In ^{2 ~10 6 Ω} · cm, claim resistance of the transfer roller to be used for the second transfer is 10 ^{2 ~10 6 Ω} · cm 1~8,1
The toner and electrophotographic apparatus according to any one of 0 to 13.